Annual Research Conference 2016

Abstract Booklet

School of Electrical and Electronic Engineering

ARC 2016 welcomes you!

On behalf of the School of Electrical and Electronic Engineering, the ARC 2016 Committee would like to offer a warm welcome to this year’s conference proceedings. It is a great honour to welcome you to the 18th Annual Research Conference at Newcastle University. The School of Electrical and Electronic Engineering at Newcastle University aims to provide a research environment in which ambitious new and original ideas can flourish and in which every individual member of staff can be research active. The School was awarded a 5A for research in the RAE 2001. Research has increased dramatically since the RAE 2001 and we have exceeded our targets for the RAE 2008. In The Sunday Times University Guide on Research Quality EEE is ranked amongst the top 5 schools in the UK. Our research work is centred on four major research groups of international standing in Communications, Sensors and Signal Processing, Emerging Technologies and Materials, Microelectronics System Design and Power Electronics, Drives and Machines. The School runs an Annual Research Conference which provides a showcase for our research students and young research staff. This annual event is an excellent opportunity for staff and research students to come together with industrial partners to celebrate the school’s research and collaborative links. It is a great networking event, where attendees can meet people from other research areas, exchange knowledge and discuss common research interests. Finally, this year will be the first ARC to have an awards ceremony of £1000 for best paper winner of each group and combined networking event at the Research Beehive, old library. This will consist of a speech given by the Vice President of the SEVCON, NI, and IET, followed by prize giving for best papers, presentations and posters. The networking event is aimed at encouraging cross-research-group networking as well as with the industrial sponsors and representatives from the IET. We hope that you find the two days interesting that you thoroughly enjoy both days of the Annual Research

Conference 2016, and take something of value and lasting memory from the two days.

Best wishes from ARC2016 Committee. Chair Vice-Chair Industrial Liaison

lijuan Xia yuqing Xu Ehsan Dehghan-Azad

Event Coordinator Media Coordinator Student Liaison

Oras Ahmed Al-Ani Ghazal Ghazaei Achonu Adejo

TIME ARC 2016 Presentations Schedule – Day One, Research Beehive

20 January 2016

08:30 - 09:00 Registration – Ground floor reception, Research Beehive.

09:00 - 09:15 Opening Plenary –Room 2.21 &2.22

09:15- 09:30 Keynote Presentation - Room 2.21 & 2.22

09:30 - 10:00 Coffee Break

SESSION I COMS2IP talks -Room 2.21 EP talks -Room 2.22

10:00 - 10:15 10:15 - 10:30 10:30 - 10:45 10:45 - 11:00 11:00 - 11:15 11:15 - 11:30

Chair: Kianoush Nazarpour Assessor: Jeffrey Neasham Xiaotian Chen Aobo Zhao Zaid Abduladheem Abdullah Ali Munthr Abdulkareem Alameer Bilal Alauldeen Jebur Adikari Kabita

10:00 - 10:15 10:15 - 10:30 10:30 - 10:45 10:45 - 11:00 11:00 - 11:15 11:15 - 11:30

Chair: Barrie Mecrow Assessor: Volker Pickert

Ruisheng Li Junnan Wang Ehsan Dehghan-Azad Jamie Lamb Deng Xu Sichao Yang

11.30-13:00 Lunch Break

COMS2IP and ETM Poster Session. Room 2.20

SESSION II COMS2IP talks-Room 2.21 µSystem talks -Room 2.22

13:00 - 13:15 13:15 - 13:30 13:30 - 13:45 13:45 - 14:00 14:00 - 14:15 14:15 - 14:30

Chair: Said Boussakta Assessor: Martin Johnston

Musab Tahseen Al-kaltakchi Mohammed A. Abdullah Benjamin Sherlock Safaa M Z Nash At-Awny Mohamad Abdulrahman Ahmed Akachukwu Belusolisa Okoli

13:00 - 13:15

13:15 - 13:30 13:30 - 13:45 13:45 – 14.00

Chair: Alex Yakovlev Assessor: Andrey Mokhov Lijuan Xia Austin J. Ogweno Nabeel A. Fattah Michael Walker

14:30 - 15:00 Tea Break

SESSION III µSystem talks -Room 2.21 EP talks -Room 2.22

15:00 - 15:15 15:15 - 15:30 15:30 - 15:45 15:45 - 16:00 16:00 - 16:15 16:15 - 16:30

Chair: Graeme Chester Assessor: Nick Coleman

Alessandro De Gennaro Kaiyuan Gao Ali Majeed Aalsaud Mohammed Al-Hayanni Jonathan Beaumont Khaled Al-Ma’aith

15:00 - 15:15 15:15 - 15:30 15:30 - 15:45 15:45 - 16:00 16:00 - 16:15 16:15 - 16:30

Chair: Dave Atkinson Assessor: Shady Gadoue

Andrew M. Jenkins He Liu Aslan S. Jalal Yang Lu Chenming Zhang Richard Mandeya

IME ARC 2016 Presentations Schedule – Day Two, Research Beehive

21 January 2016

SESSION IV COMS2IP talks -Room 2.21 µSystem talks -Room 2.22

08:45 – 09:00 09:00 - 09:15 09:15 - 09:30 09:30 - 09:45 09:45 - 10:00 10:00 - 10:15 10:15 - 10:30

Chair: Mohsen Naqvi

Assessor: Maninder Pal

Saadoon A. M. Al-Sumaidaee Ruslee Sutthaweekul Wael Abd Alaziz Mingye Dai Ali Jaber Abdulwaham Al-Askery Yasir Ahmed Al Mathehaji Ghazal Ghazaei

08:45 – 09:00 09:00 - 09:15 09:15 - 09:30 09:30 - 09:45 09:45 - 10:00

Chair: Patrick Degenaar Assessor: Rishad Shafik

Mohammed I. T. Al-Daloo Yuqing Xu Vladimir Dubhikhin Mohamed A. Abufalgha Issa H. Qiqieh

10:30 -11:00 Coffee Break

SESSION V COMS2IP talks -Room 2.21 EP talks -Room 2.22

11:00 - 11:15 11:15 - 11:30 11:30 - 11:45 11:45 - 12:00 12:00 - 12:15 12:15 - 12:30

Chair: Gui Yun Tian Assessor: Emma Bruntun

Raid Al-Nima Pengming Feng Harith Fakrey Tahir Al-Shwaily Jafaar Mohammed Al-Khasaraji Ghanim Abdulkareem Al-Rubaye Di Wu

11:00 - 11:15 11:15 - 11:30 11:30 - 11:45 11:45 - 12:00 12:00 - 12:15 12:15 - 12:30

Chair: Matthew Armstrong Assessor: Mohamed Dahidah

Muhsien Mohammed Yazid Mehmet Caglar Kulan Liam Alexander Naugher Mohamed Awad Mohamed Xiang Lu Ahmed Alturas

12:30-13:30 Lunch Break

EP and µSystem Poster Session. Room 2.20

SESSION VI ETM talks -Room 2.21 COMS2IP talks -Room 2.21

13:30 - 13:45 13:45 - 14:00 14:00 - 14:15 14:15 - 14:30 14:30 - 14:45 14:45 - 15:00

Chair:Noel Healy

Assessor: Jon Goss

Nurul Syazwina Binti Mohamed Srinivas Ganti Marzaini Rashid Oras Ahmed Shareef Al-Ani Chloe Victoria Peaker Sherko Ghaderi

13:30 - 13:45 13:45 - 14:00 14:00 - 14:15 14:15 - 14:30 14:30 - 14:45 14:45 - 15:00 15:00 - 15:15 15:15 - 15:30 15:30 - 15:45

Chair: Satnam Dlay Assessor: Aissa Ikhlef Waqas Rafique Mohammed Dahiru Buhari Zhen Mei Achonu Oluwole Adejo Dong Zhou Alaa Hussain Ahmed Jamal Ahmed Hussein Ali Imam Sunny Yulong Chen

TIME ARC 2016 Presentations Schedule – Day Two, Research Beehive

21 January 2016

16:00–16:15 Tea Break

SESSION VII COMS2IP talks -Room 2.21 EP talks -Room 2.22

16:15 - 16:30 16:30 - 16:45 16:45 - 17:00 17:00 - 17:15 17:15 - 17:30

Chair: Charalampos Tsimenidis Assessor: Stephane Le Goff

Sinan Husam Mahdi AlKassar Sameer Alsudany Mahammad Majed Fakhir Ahmed SattarHadi Al Tmeme Hasan Mohammad Kadhim

16:15 - 16:30 16:30 - 16:45 16:45 - 17:00 17:00 - 17:15 17:15 - 17:30

Chair: Glynn Atkinson Assessor: Nick Baker

Weichi Zhang Osama Sh Mohamed Abushafa Ruchao Pupadubsin Huaxia Zhan Jiankai Ma

17:30-18:00 Drinks Reception

18:00-18:30

Closing Plenary - IEEE Committee Presentation Ceremony - Dr Glynn Atkinson, Postgraduate Research

Director, School of EEE, Room 2.21 and 2.22.

ARC 2016 Poster Presentations Schedule – Day One, Research Beehive

11:30, 20 January 2016,

COMS2IP posters –Room 2.20 Chair: Rajesh Tiwari

1. Fahad Abdalrahman Alsifany

2. Hayfaa Talib Hussein

3. Zeyu Fu

4. Mahmoud Algeli

5. Yang Sun

6. Chaoqing Ran

7. Yachao Ran

8. Denis ljike Ona

9. Huan Cao

10. Israa Ali Abdulrazaq Al-Shaikhli

11. Ahmad Nashwan Abdulfattah

12. Jiachen Yin

ETM posters -Room 2.20

Chair : Sarah Olsen

13. Johannes Gausden

14. Hind Ateeg T Alsnani

15. Idris Muhammed

16. Tiago Marinheiro

17. Fatimah Hameed Khaleel

18. Faiz bin Arith

19. Andrew Douglas Reid

20. Luke Bragley

ARC 2016 Poster Presentations Schedule – Day Two, Research Beehive

12:30 , 21 January 2016

EP posters –Room 2.20 Chair: Kristopher Smith

1. Ilias Sarantakos

2. Stalin Eloy Munoz Vaca

3. David Frederick Mecrow

4. Mohammad Abdul Hakin Raihan

5. Yaohui Gai

6. Fangbo Liu

7. Ari Akbar Al-Jaf

8. Yerasimos Yerasimou

9. Hamza Khalfalla

µSystem posters -Room 2.20

Chair: Alex Bystrov

10. David Burke

11. Konstantinos Goutsos

12. Matthew Travers

Maps of the Research Beehive

Guests and sponsors

Opening plenary - Professor Bryn Jones

Dean of Postgraduate Studies

He has been employed by Newcastle University since 1990. His first post was as a scientific officer in the Fossil Fuels and Environmental Geochemistry Postgraduate Research Institute. In 2002, following a University re-structuring, He was appointed Director of Postgraduate Studies in the School of Civil Engineering and Geosciences. He continued in this role until mid-2006 when He became Dean of Postgraduate Studies in the Faculty of Science, Agriculture and Engineering. Having completed my initial (2006-2009) term, his appointment as Dean was extended for a further two years (2009-2011) and subsequently for a further five years (2011-2016).

From November 2013 until January 2015, he was seconded to become the first Head of Academic Operations at Newcastle University International Singapore (NUIS). As Head of Academic Operations, he had oversight of academic staff at NUIS and accountability for the academic performance and management of NUIS programmes. Over the years he has held many other roles within the University. He has been a Degree Programme Director and chair of Boards of Studies and Boards of Examiners. He has chaired the University's eLearning and Student Information Committee and its Researcher Development Co-Ordination Group, as well as the Faculty Graduate School Committee. I have played a role in a number of significant projects generating funding for postgraduates, facilitating postgraduate placements with business, improving the experience of postgraduate students, developing initiatives in doctoral education and supporting the international activities of the University. In 2012, I became Newcastle University's academic lead for Brazil and led the development of the University's Brazil Strategy.

Primary Sponsor – SEVCON

Sevcon manufactures high quality motor controllers and system components for electric vehicles - impacting on the way people around the world travel, work and live.

Sevcon offer a diverse range of products on electrically powered vehicles from fork lift trucks to electric cars and bikes. These components - whether for on-road or off-road vehicles - are constructed to perform reliably in the most severe conditions. Priding ourselves on our products with a dedication to design and development, we are constantly evolving to meet the needs of our customers. Sevcon operates worldwide from our headquarters in Gateshead, UK, and from subsidiaries in France, Japan, Korea, and the USA.

Sevcon has recognised that quality of service and product is essential to customers and is a key component of success. In 1994 we became accredited to ISO9000, which means that we have a strong quality policy and system in place, regularly review our products and work to improve on them. We are a world class supplier in the industry and work to the requirements of QS9000 and TS16949.

Sevcon is equally dedicated to investment in design and development, evolving products and services to serve its present and future markets better. We have a powerful history of innovation, application expertise and customer support. This means that our products are reliable and durable, with a low energy output and low lifetime costs.

Keynote presentation – Dr. Peter Barrass Vice President of Engineering of Sevcon

Peter has a Master’s degree in Electrical and Electronic Engineering from Leeds

University UK and gained a PhD from Newcastle University UK on the subject of High

Performance Switched Reluctance Drives. His first employer was GEC TDPL (now

ALSTOM) where he worked on various aspects of High Voltage DC transmission, Static

VAR Compensators, naval and rail traction power systems. He joined Control

Techniques in 1995 where he worked on the successful Unidrive range of variable speed

drives becoming Power Design Manager in 1999. In 2003 he joined Sevcon as Vice

President of Engineering. He has authored and co-authored several papers and a book on the subject of power

electronics, drives and motor control. Peter holds several patents and is a member of the IET and IEEE. Outside

work he likes to spend time with his family and keeping fit cycling and walking.

Our second sponsor – National Instruments

When it comes to innovation, progress is collaborative.

For nearly 40 years, NI (ni.com) has worked with engineers and scientists to provide answers to the most challenging questions. Through these pursuits, NI customers have delivered hundreds of thousands of products to market, overcome innumerable technological roadblocks, and engineered a better life for us all. If you can turn it on, connect it, drive it, or launch it, chances are NI technology helped make it happen. Through the work of NI customers, we are seeing the type of societal and technological impact within our DTlifetimes that would have once been impossible. NI’s platform-based approach—a unified software architecture and modular, programmable hardware—reduces the complexity of smart, connected systems and helps engineers innovate faster, and easily integrate new technologies as they become available.

You can’t build systems to solve the challenges of tomorrow based on the infrastructure and standards available today. That’s why NI innovates for the future, based on next-generation system architectures, to ensure that our customers stay ahead of the technology curve. With these powerful, off-the-shelf NI solutions, engineers and scientists can tailor their systems to meet their needs now and in the future.

Web: http://uk.ni.com/

Our Academic Partner – IET

'IET is one of the largest engineering institutions with over 163,000 members. A multi-disciplinary organisation which reflects the diverse nature of engineering in the 21st century. IET is working to engineer a better world by inspiring, informing and influencing our engineers and technicians and those who are touched by engineering.' We would like to thank you IET for providing us sponsorship , literature and copies of E&T magazine , Newcastle University are an IET Academic Partner as they understand the value in professional development and being affiliated with professional body at an early stage. As much, the university will fund IET student membership for its PhD students in Electrical and Electronic engineering. To find out more about IET membership, please visit the IET stand or see our website : http://theiet.org/

We would like to thank the IEEE Newcastle University student branch for their complementary bundle.

Abstracts ____________________________________________

Communications, Sensors, Signal & Information Processing

Presentations

____________________________________________

Active 3D Surface Thermography for ECPT

Xiaotian Chen

The use of infrared camera to obtain heat surface information is wildly applied in areas such as biomedical engineering, NET & E and heat transfer investigation for building and machines. The 2D infrared thermography have been well studied, however, the thermal image is strongly affected by the viewing angle of the infrared camera because of the directional emissivity. This article proposed a new method by integrating RGB-D camera and thermal infrared camera to generate real-time 3D temperature surface. A new calibration method is proposed for infrared camera and depth camera. The 3d point cloud will also help to correct the directional emissivity error for thermal image. We will show our experiment result on our ECPT (Eddy Current Thermography System).

____________________________________________ Using Meander Line Structure for UHF RFID based Corrosion and Crack Sensing

Aobo Zhao, Guiyun Tian and Jun Zhang

UHF RFID is an emerging technology to bridge the gap between NDT and SHM. Sensitivity and communication ability in metallic environment are two main challenges of applying RFID for sensing applications. Using meander line antenna based sensor can achieve the balance between sensitivity and communication through centralised current distribution and impedance matching. Experiment results show that different stages of corrosion can be distinguished through resonance frequency shift of the antenna.

____________________________________________ Using Meander Line Structure for UHF RFID based Corrosion and Crack Sensing

Zaid Abdullah, Charalampos Tsimenidis and Martin Johnston

Massive Multiple-Input-Multiple-Output (MIMO) systems are a state of the art research area in wireless communications. Massive MIMO can significantly improve the system performance and capacity by using a large number of antenna elements at the base station (BS). However, this increases the system complexity, power consumption and hardware cost. Low complexity Antenna selection techniques can reduce the system complexity and hardware cost by choosing the best antenna subset and keeping the system performance at a certain required level. Bio-inspired optimization techniques are commonly used in many different engineering applications and are known for their low complexity while at the same time finding the best solution for a certain optimization. In this paper, Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) algorithms are investigated to develop low complexity antenna selection techniques for massive MIMO systems and achieve a performance comparable with the higher complexity optimal antenna selection.

____________________________________________ An elastic net-regularized HMAX model of visual processing

Ali Alameer, Patrick Degenaar and Kianoush Nazarpour

The hierarchical MAX (HMAX) model of human visual system has been used in robotics and autonomous systems widely. However, there is still a stark gap between human and robotic vision in observing the environment and intelligently categorising the objects. Therefore, improving models such as the HMAX is still topical. In this work, in order to enhance the performance of HMAX in an object recognition task, we

augmented it using an elastic net-regularised dictionary learning approach. We used the notion of sparse coding in the S layers of the HMAX model to extract mid- and high-level, i.e. abstract, features from input images. In our model, the sparse coefficients calculated by the elastic net-regularised dictionary learning algorithm were used to train and test the model. With this setup, we achieved a classification accuracy of 82.6387%∓3.7183%averaged across 5- folds which is significantly better than that achieved with the original HMAX.

____________________________________________ Performance Analysis of OFDM-Based Denoise-and-Forward Full-Duplex PLNC with

Imperfect CSI

Bilal Jebur, Charalampos Tsimenidis and Martin Johnston.

In this paper, we propose a full-duplex physical-layer network coding (FD-PLNC) scheme for frequency-selective multipath channels using orthogonal frequency-division multiplexing (OFDM). We consider a network scenario of two-way relay channels (FD-TWRCS) with two source nodes, A and B, intending to exchange information with the aid of a relay node R. All nodes operate in full-duplex mode and are equipped with two antennas dedicated for transmission and reception, respectively. Moreover, the proposed FD-PLNC system is combined with an active self-interference cancellation scheme in order to minimize the effect of self-interference and its performance is investigated in the presence of channel estimation errors. Semi-analytical bit error rate performance (BER) expressions as a function of the signal to noise ratio (SNR) are derived to describe the end-to-end performance. Furthermore, simulation based performance results show a close match with the derived semi-analytical solutions demonstrating the feasibility of FD-PLNC using the active self-interference cancellation scheme.

____________________________________________ Fusion Features Based On Speaker Recognition

Musab Tahseen Salahaldeen Al-Kaltakchi, Wai Lok Woo, Satnam S. Dlay and Jonathon Chambers

Speech biometrics are used to recognize an individual’s voice for speaker identification tasks. The proposed system consists of three stages: feature extraction and normalization, acoustic modelling and decision fusion. Mel Frequency Cepstral Coefficients (MFCC) are efficient for speaker identification in clean speech while Power Normalized Cepstral Coefficients (PNCC) features are robust for noisy environments. Therefore, combining both features together is better than taking each one individually. In addition, Cepstral Mean and Variance Normalization (CMVN) and Feature Warping (FW) are used for feature normalization mitigate possible channel effect and the channel mismatch in voice measurements. Acoustical environment modelling is based on a Gaussian Mixture Model (GMM) with Maximum A posterior Probability (MAP) adaptation applied to the means of the universal background model (UBM). Finally, fusion maximum, mean and weighted sum are used to modify the Speaker Identification Accuracy (SIA). Verifications conducted on the TIMIT database with and without noise performance improvement.

____________________________________________ Iris Recognition Performance under the Visible and Near-Infrared Imaging: Comparisons

and Fusion

Mohammed A. M. Abdullah, Jonathon Chambers, Wai Woo and Satnam Dlay

Most of the commercially available iris recognition systems operate in the Near-Infrared (NIR) spectrum due to the clarity of the dark pigmented iris texture under the NIR spectrum. Recently, Visible Light (VL) iris imaging has attracted researchers due to the interest in the iris recognition at a distance for security applications. Nonetheless, limited numbers of wok have compared the iris biometric performance under both the VL and NIR imaging or the fusion between them. This work aims to evaluate the performance of the iris biometric under both the VL and NIR spectra using images taken from the same subject and the fusion between them. Experimental results indicate

that the VL and NIR images provide complementary features for the iris biometric and their fusion improves the recognition performance considerably.

____________________________________________ Signal and Receiver Design for Low-Power Acoustic Communications Using M-ary

Orthogonal Code Keying

Benjamin Sherlock

Low-power, low received signal-to-noise-ratio (SNR) signals have potential for reducing the impact on marine life from acoustic communications. Here we explore the use of bandlimited pseudo-noise m-ary orthogonal code keying (M-OCK) scheme using m-sequences. Analysis and simulation of receiver structure for synchronisation and data demodulation performance is carried out. Real-world channel experiments with transmission power for the M-OCK sequences limited to less than 1W acoustic power (170.8dB re 1μPa at 1m) and transmission range varied from 100 m to 10 km in the North Sea. Synchronisation at 10 km is achieved with effective received signal-to-noise-ratio of less than -9.96dB, and data demodulation of 140.7bit/s raw throughput with pre-coding bit-error-rate (BER) 0.5 X 10-1 (symbol-error-rate (SER) 0.1) and 46.9bit/s raw throughput with pre-coding BER 0.9 X 10-3 (SER 1.95 X 10-3). Error-free synchronisation and data demodulation is achieved at ranges up to 2km, demonstrating data rates in excess of 140bit/s.

____________________________________________ Hierarchical Modulation OFDM for Physical Layer Network Coding Channel

Safaa Nash'At Awny, Charalampos Tsimenidis and Aissa Ikhlef

In this work, Hierarchical Modulation (HM) is proposed as a practical implementation of Superposition Coding (SC) scheme, offering a different degree of protection to the transmitted data according to their comparative importance. The main concept is to merge two different streams at the modulation level, the High Priority (HP) stream and the Low Priority (LP) stream, which select the quadrant and the position inside the quadrant, respectively. Furthermore, using PNC-OFDM to remedy the relay problem by using an appropriate modulation, in order to enhance the performance, to improve overall spectral efficiency. This scheme improves the system throughput by analysing the error performance of the physical layer network coding (PLNC) over AWGN channels. It is assumed that a two way relay network (TWRN) will help the two end nodes to communicate, where each node transmits the data using a single antenna and operates in a half-duplex mode.

____________________________________________ Self-interference Cancellation for Coded Full-Duplex MIMO Systems

Mohamad Abdulrahman Ahmed, Charalampos C. Tsimenidis and Stephane Y. Le Goff

In this paper, we propose and analyse the performance of a coded full-duplex (FD) bidirectional transceiver with multiple-input multiple-output (MIMO) antennas, in the presence of self-interference-cancellation (SIC). We propose an adaptive Minimum Mean-Squared-Error (MMSE) filter used in conjunction with a soft parallel interference cancellation (SPIC) to suppress the residual self-interference (SI) remaining after applying passive and active approaches to the received signal in the analog and digital domains, respectively. Convolutional and turbo codes based channel coding is considered. The system's performance in terms of Bit-Error Rate (BER) as a function of the signal to noise ratio (SNR) is evaluated over MIMO Rayleigh fading channels in the presence of additive white Gaussian noise (AWGN). Furthermore, Quadrature Phase Shift Keying (QPSK) is utilized as modulation scheme. The results demonstrate a significant improvement in BER performance as a result of the proposed iterative method that mitigates SI considerably.

____________________________________________

Femur Segmentation using an Interactive Livewire Algorithm

Akachukwu Okoli and Satnam Dlay

A livewire segmentation algorithm that aids the user in delineating medical structures is implemented. The feature of interest is the human femur in this instance. While manual segmentation is still employed by experts in medical domains, it is quite laborious and time consuming. Here Canny edge cost and Laplacian edge cost are combined along with the image gradient magnitude and image gradient direction and used to compute a cost function which is used to guide the segmentation of the femur. Results show that the livewire method outperforms the manual method within a certain range and is obviously faster than the manual method.

____________________________________________ New Facial Expression Classification Method based upon Histogram Sequence of the Local

Gabor Gradient Code-Horizontal Diagonal Descriptor

Saadoon Al-Sumaidaee

We propose a method for the facial expression classification by constructing a new layer structure that compound from the local gradient features based on the Gabor’s coefficients. Hence, we combine the Local Gradient Code-Horizontal Diagonal (LGC-HD) descriptor with set of the Kernel Gabor Filters (KGFs). Firstly, we extract the Gabor Features Map (GFM) by convolving each image with five scales and eight orientations of the KGFs. Then, we apply the LGC-HD descriptor on the output of each image in the GFM to obtain the new Local Gabor Gradient Code-Horizontal Diagonal descriptor (LGGC-HD). Consequently, a sequence of the histogram features of the LGGC-HD descriptor is calculated from the 42 blocks of each image in the GFM. We classified each expression based on the histogram features by measuring the distance among other expressions. The experimental results on the JAFFE database demonstrated the efficiency of the proposed method compared to the other methods.

____________________________________________ Steel Corrosion Stage Characterisation using Open-Ended Waveguide Probe

Ruslee Sutthaweekul and Guiyun Tian

This paper proposes a novel measurement method for corrosion stage characterisation using open-ended waveguide probes. To study the effect of the different operational frequency, two open-ended rectangular waveguide probes: WR-62 and WR-42 with operating frequency bands of Ku-band and K-band respectively were used. To investigate the influences of common and different parameters, three sets of samples are studied: two sets of the uncoated and coated corrosion progression samples (1, 3, 6, 10, and 12 months) and a set of four different surface preparation samples. The waveguide probes in conjunction with vector network analyser (VNA) can measure reflection coefficients (S11) under sweeping frequency, above the samples. To deal with multiple parameters influences, principal component analysis (PCA) methods are also applied to analyse the major influences of the corrosion samples with different surface preparation processing, coating and corrosion progression stages and quantitative analysis.

____________________________________________ Non-Binary Turbo Codes on Additive Impulsive Noise Channels

Wael Abd Alaziz, Martin Johnston and Stephane Le Goff

It is well known that binary error-correcting codes with iterative decoders can achieve near Shannon-limit performance on the additive white Gaussian noise channel, but their performance on more realistic wireless channels becomes degraded due to the presence of burst errors or the noise at the receiver having a non-Gaussian distribution due to random impulses caused by interference. Non-binary codes are known to be effective in correcting burst errors, but there is no research reported in the literature investigating non-binary codes on impulsive noise channels. In this paper, we will investigate the performance of non-binary turbo codes defined in finite fields on symmetric alpha-stable impulsive noise channels and compare with binary turbo codes, employing a Cauchy receiver to mitigate the effects of the channel.

____________________________________________ Channel State Information Acquisition for Massive MIMO

Mingye Dai, Charalampos Tsimenidis and Said Boussakta

Massive multiple-input multiple-output (MIMO) system is a promising technology for next-generation of wireless communications. Channel state Information (CSI) at the BS is a critical role in massive MIMO system and usually obtained with the assistance of training signals. However, as the number of UT antenna grows, the pilot overhead could significantly decrease the system efficiency, which would be the system bottleneck. To reduce the pilot overhead, block type pilot is considered as a solution instead of comb type pilot. Furthermore, spreading sequences such as gold sequences could be utilized as pilot signals due to its bounded small cross-correlation within a set. Combined with Orthogonal Frequency Division Multiplexing (OFDM), this could be a way to eliminate the interference from other antennas within a cell during the training period.

____________________________________________ LDPC Coded Massive MIMO OFDM system

Ali Al-Askery, Charalampos Tsimenidis, Said Boussakta and Jonathon Chambers

In this paper, a novel approach is performed to find the actual probability density function (PDF) of the noise post the Multiple-Input-Multiple- Output (MIMO) detector. The receiver is designed with Zero-Forcing (ZF) detector by approximating the matrix inversion formula with Neumann series approximation. To verify the accuracy of this PDF compared to the histogram plot of the actual PDF, we have plotted both PDFs and the result have shown close match compared to the histogram of the actual noise PDF. Next, this PDF is used to design the Log-Likelihood Ratio (LLR) for the Low Density Parity-Check (LDPC) coded massive MIMO-OFDM systems. The simulation results have shown 1 dB improvement in the performance of the LDPC coded system compared to using Gaussian PDF.

____________________________________________ Reliable Distributed Broadcast Protocol in Multi-hop Cognitive Radio Ad Hoc Networks

without a Common Control Channel

Yasir Al-Mathehaji, Said Boussakta and Martin Johnston

Cognitive radio (CR) technology is a promising technology that aims to enhance the spectrum utilization through enabling the unlicensed users to opportunistically use the vacant spectrum bands assigned to the licensed users. Broadcast is one of the most classical operations in the wireless networks, as well as in cognitive radio network. However, it is not trivial to extend traditional broadcasting methods to CRNs. In this paper, we proposed a novel distributed broadcast protocol that specifically address the problems: the reliable data dissemination, transmitters-receivers synchronization, and PR users’ communication protection in cognitive radio networks. Our proposed protocol explicitly considers the spatial variation of the spectrum opportunities and different local topologies and dynamically allocates the transmitting/receiving channels within each node. Simulations are conducted to examine the performance of the proposed protocol, which confirmed that it provides better CR network performance.

____________________________________________ An exploratory study on the use of convolutional neural networks for object grasp

classification

Ghazal Ghazaei, Patrick Degenaar, Graham Morgan and Kianoush Nazarpour.

The loss of hand profoundly affects an individual’s quality of life. Prosthetic hands can provide a route to functional rehabilitation by allowing the amputees to undertake their daily activities. However, the performance of current artificial hands falls well short of the dexterity that natural hands offer. The aim of this study is to test whether an intelligent vision system could be used to enhance the grip functionality of prosthetic hands. To this end, a convolutional neural network (CNN) deep learning architecture was implemented to classify the objects in the COIL100 database in four basic grasp groups: tripod, pinch, palmar and palmar with wrist rotation. Our preliminary, yet promising, results suggest that the additional machine

vision system can provide prosthetic hands with the ability to detect object and propose the user an appropriate grasp.

____________________________________________ Personal verification based on finger textures

Raid Al-Nima, Satnam Dlay, Wai Lock and Jonathon Chambers

In this paper, a comparison method to extract the Finger Texture (FT) of the main four finger images (index, middle, ring and little) from contactless and very low resolution hand images is proposed. Moreover, feature extraction was applied based on adopting image processing to solve the illumination problem and increase the contrast of the FTs. Then the pre-processed image was segmented and prepared for the next intelligent authentication process, where an Artificial Neural Network (ANN) technique is used as to evaluate the personal recognition performance. A large database from the Hong Kong Polytechnic University Contact-free 2D Hand Images Database version 1.0 has been used in this work. The results showed that our proposed algorithm for the finger extraction has a comparable performance in terms of collecting more features compared to other publications. Furthermore, our proposed feature extraction model has been succeeded and achieved a good indication.

____________________________________________ Variational Bayesian PHD filter with Deep Learning Network Updating for Multiple Human

Tracking

Pengming Feng, Wenwu Wang, Syed Mohsen Naqvi and Jonathon Chambers

We propose a robust particle probability hypothesis density (PHD) filter where the variational Bayesian method is applied in joint recursive prediction of the state and the time varying measurement noise parameters. The proposed particle PHD filter is based on forming variational approximation to the joint distribution of states and noise parameters at each frame separately; the state is estimated with a particle PHD filter and the measurement noise variances used in the update step are estimated with a fixed point iteration approach. A deep belief network is used in the update step to mitigate the effect of measurement noise which is trained based on both colour and oriented gradient histogram features. Simulation results using sequences from the CAVIAR dataset show the improvements of the proposed DBN aided variational Bayesian particle PHD filter over the traditional particle PHD filter.

____________________________________________ On the Optimality of Location-Dependent Key Management Protocol for a WSN with a

Random Selected Cell Reporter LKMP-RSCR

Harith Al-Shwaily, Martin Johnston and Rajesh Tiwari

Wireless sensor networks (WSNs) employed to be used in the applications of smart cities can be widely deployed, but are vulnerable in terms of disseminated data security. So that, confidentiality, availability and authenticity of mentioned data must be guaranteed. Several key management schemes had been proposed to ensure these requirements. The most common schemes depend on the sensor location to generate the security credentials. This paper investigate the optimum setting of our location-dependent key management protocol with random selected cell reporters (LKMP-RSCR). In this protocol, the generated report of an event involve a third level of endorsement implemented by a set of cell reporters. As a result, the adversary must compromise the entire set of cell reporters to generate a bogus report from a particular region. Mathematical evaluation is presented for the ELKMP-RSCR, comparing to the LEDS and MKMP schemes, our scheme outperform others significantly.

____________________________________________ Performance analysis of FEC codes for short range underwater optical wireless

communication

Jafaar Alkhasraji and Charalampos Tsimenidis

Investigation of the oceans has been growing in recent years owing to massive undersea resources which are still under exploration. Despite radio electromagnetic waves EMWs’ suffer from high attenuation in water body. Acoustic frequency has the ability to transmit data over a long distance in oceans. However, there are obstacles such as limited bandwidth and low data rate as a result of multi-path reflection even at short range. The challenges limit the researchers’ options to transmit and collect a large amount of data. Therefore, underwater based on optical wireless communications UWOCs’ promises an indispensable choice to achieve these requirements for short ranges. In this paper, an underwater optical wireless communication system with Orthogonal Frequency Division Multiplexing OFDM and Quadrature Amplitude Modulation QAM modulation with low density parity check LDPC error correction coding scheme has been introduced in order to improve the robustness and reliability of underwater optical channel.

____________________________________________ Improved performance of binary/non-binary LDPC coded OFDM in impulsive power line

channels

Ghanim Al-Rubaye, Charalampos Tsimenidis and Martin Johnston

Currently, power-line communication (PLC) channels becomes an emerging technology that uses the indoor grid for high data transmission, due to the existing of wiring infrastructure, it becomes an economical communication with cheap installation. On the other hand, PLC has a harsh medium for communication due to high attenuation, frequency selectivity and impulsive noise. In this paper, we propose Binary/Non-Binary Low Density Parity Check (B/NB-LDPC) codes to overcome these problems. Therefore, the performance of both decoders is improved using optimum construction of the parity check matrix H by progressive edge growth (PEG) algorithm with a novel log likelihood ratio (LLR) of each decoder to mitigate the highly impulsive noise in PLC channels. Numerical results show that the proposed NB-LDPC-OFDM gives more than 21 dB and more than 6 dB coding gains compared to uncoded system and the proposed B-LDPC-OFDM respectively at Pe=10-4.

____________________________________________ NMF2D based source separation using Extreme Learning Machine

Di Wu

In this paper, we study Non-negative Matrix Two-Dimensional Factorization (NMF2D) based Single Channel Source Separation (SCSS) using a newly proposed algorithm named Extreme Learning Machine (ELM). Compared with other machine learning algorithms such as Support Vector Machines and Neural Networks, ELM can provide better generalization performance and a much faster learning speed. Unlike conventional researches that concentrate on generating masks for each source, we use ELM to classify estimated sources separated by NMF2D algorithm. The experiment results show that the performance of proposed method is improved not only in training and testing speed, but also in the quality of separated signal compared with using DNNs and NMF2D.

____________________________________________ Speech Source Separation using the IVA Algorithm with Multivariate Mixed Super Gaussian

Student’s t Source Prior in Real Room Environment

Waqas Rafique, Syed Mohsen Naqvi and Jonathon Chambers

Independent vector analysis (IVA) can theoretically avoid the permutation problem in frequency domain blind source separation by using a multivariate source prior to retain the dependency between different frequency bins of each source. In this paper a mixture of multivariate super Gaussian distribution and multivariate Student’s t distribution is adopted as a source prior for the IVA algorithm. The Student’s t distribution due to its heavy tail nature can better model the high amplitude information in the frequency bins and at the same time a dependent super Gaussian distribution can be adopted to model other information in frequency bins. The weight of both distributions can be varied in source prior mixture and their separation performance is tested over different scenarios by using the binaural room impulse responses (BRIRs). All the experimental

results confirm that the IVA with proposed mixed super Gaussian-Student’s t source prior can consistently achieve improved separation performance.

____________________________________________ Optimal OFDM Subcarrier Design for SAR Cross-range Profile Reconstruction

Mohammed Dahiru Buhari, Gui Yun Tian and Rajesh Tiwari

In this paper, we investigate an optimal Orthogonal Frequency Division Multiplexing (OFDM) subcarrier design for a Synthetic Aperture Radar (SAR) system that can be used in Through-the-Wall radar Imaging (TWI), detection of hidden object and pipelines inspection. At first, an OFDM SAR model is developed for a single target detection. The target is reconstructed via match filtering of the estimated phase history with a reference function. The phase history is estimated using Least Square Estimate (LSE) and parameters such as Root Mean Square Error (RMSE), cumulative side lobe levels and the main lobe width are used to test and compare the accuracy of the reconstruction process. Simulation results shows that increasing the number of subcarriers results in an improvement in the target reconstruction but at the cost of having a wider main lobe. The results are also compared with the Single Frequency (SF) case. Initial results shows that OFDM SAR method is a promising technique in SAR reconstruction process as compared with SF case such as Frequency Modulated Continuous Wave (FMCW). The technique is later extended to the detection of multiple targets scene.

____________________________________________ Finite Length Analysis of LDPC codes on Impulsive Noise Channels

Zhen Mei, Martin Johnston, Stephane Le Goff and Li Chen

Low-Density Parity-Check (LDPC) codes are well known to approach the Shannon capacity when their length is very long, but their performance is degraded for short lengths. Finite length analyses of LDPC codes have already been presented in the literature for the AWGN channel, but in this paper we consider the analysis of short LDPC codes for channels that exhibit impulsive noise. Density evolution is applied to evaluate the asymptotic performance of LDPC codes on impulsive noise channels and determine the threshold signal-to-noise ratio. We then derive closed expressions for the bit and block error rate of short LDPC codes on these channels, which match closely with simulated results on channels with different levels of impulsiveness for block lengths as low as 1000 bits.

____________________________________________ Resource allocation for irregular Macro Base station deployment using Self-Organization

Achonu Adejo, Said Boussakta and Jeffrey Neasham

A major challenge in current cellular networks like the Long Term Evolution (LTE) is the intense demand for data. Heavy data is needed to drive applications that run on devices like smartphones, tablets and PCs. Soft Frequency reuse (SoftFR) is a technique used to implement reuse of the limited frequency spectrum while guaranteeing reduced interference in the system. In this paper, we propose a self-organized technique that efficiently performs the SoftFR algorithm when the Macro BS deployment is considered to be irregular. Our results give improvements in the system capacity over static SoftFR implementations. This research will aid the analysis and optimization of practical cellular network deployments which are not always hexagonal but form irregular patterns. It is also a precursor to our research in optimizing SoftFR in heterogeneous cellular networks.

____________________________________________ Buffer-Aided Relay system with physical layer network coding

Dong Zhou UHF RFID is an emerging technology to bridge the gap between NDT and SHM. Sensitivity and communication

ability in metallic environment are two main challenges of applying RFID for sensing applications. Using

meander line antenna based sensor can achieve the balance between sensitivity and communication through

centralised current distribution and impedance matching. Experiment results show that different stages of

corrosion can be distinguished through resonance frequency shift of the antenna.

____________________________________________ AF-PNC for frequency selective channels with 16-QAM modulation using DFE

Alaa Ahmed, Charalampos Tsimenidis and Jeffrey Neasham

Physical layer network coding (PLNC) is a very efficient scheme when it comes to bandwidth saving. Direct implementation of this scheme is not possible in frequency selective channels. Such channels are not uncommon and cause intersymbol interference (ISI). One of the best ways to deal with these channels is by using a decision feedback equalizer (DFE). The proper way of using this DFE in such systems is shown with optimal design and simulated end to end performance. Moreover, the feasibility of the proposed method is checked for 16-QAM and/or higher modulation schemes without further adjustments. The computational complexity is in the same order as that of one DFE equalizer at the end nodes and no computations of any kind are required at the relay.

____________________________________________ Outage Performance of a Multi-User Underlay Cognitive Radio Network

Jamal Hussein, Said Boussakta and Charalampos Tsimenidis

In this paper, the outage performance of a dual-hop amplify-and-forward multi-user underlay cognitive relaying network is investigated. An expression is derived for the cumulative distribution function (CDF) of the equivalent signal-to-noise ratio (SNR). From the derived CDF, the outage performance of the cognitive network is thoroughly investigated. Furthermore, simple and generic asymptotic expression for the outage probability is obtained and discussed. The asymptotic result show that opportunistic scheduling has no impact on diversity gain. It is confirmed that the array gain determines the SNR advantage of opportunistic scheduling over the single user scenario. Finally, numerical results and Monte Carlo simulations are also provided to support the correctness of the analytical calculations.

____________________________________________ LOW FREQUENCY (LF) RFID SENSOR SYSTEM FOR STRUCTURAL HEALTH

MONITORING (SHM) AT HIGH TEMPERATURE ENVIRONMENT

Ali Imam Sunny and Gui Yun Tian

Structural health monitoring at high temperature environment is vital particularly in petrochemical industries where processes conduct at 150°C or more. In such conditions, corrosion and rust formation is a major cause of deterioration to metallic structures. Current inspection methods used to detect any deterioration requires removal of thermal insulation layer to gain access to the metallic surface which requires shutting down of operations and are an expensive process. This paper will demonstrate the use of LF RFID sensors for SHM at high temperature conditions. Presence of corrosion on the sample will cause impedance change on which will be analysed in this paper. Furthermore, the response characteristics of commercial RFID tags placed on hot metallic samples will cause further significant impedance variation which will be compensated by feature extraction and selection of features. Enhanced sensing efficiency in the harsh environment at high temperature will be developed.

____________________________________________ An improved precoding design for downlink massive MIMO systems

Yulong Chen, Said Boussakta and Charalampos Tsimenidis

Massive multiple input multiple output (MIMO) is an emerging technology for future wireless networks, scaling up conventional MIMO to an unprecedented number of antennas at base stations (BS). In terms of massive MIMO, precoding design is an active research for downlink transmission, because high channel capacity performance can be achieved by precoding. Compared with nonlinear precoding such as the capacity-achieving dirty paper coding, previous studies have shown that some linear precoding methods can

achieve close to optimal capacity performance. Therefore, because of lower complexity, linear precoding is always regarded as an effective solution in massive MIMO systems. Assume that in time division duplex systems, we can obtain the perfect channel state information from uplink channel by utilizing the reciprocity of the wireless medium. One potential scheme is partitioning precoding matrix into several steps and then respectively improve these steps by optimization methods such as polynomial expansion and convex optimization.

____________________________________________ Efficient Sclera Vein Segmentation Method with Images Captured At-A-Distance and On-

The Move

Sinan Alkassar, Jonathon Chambers, Satnam Dlay and Lok Woo

Sclera blood veins have been investigated recently as an efficacious biometric trait. The sclera has a rich pattern of blood vessels which have different orientations and layers. Capturing this part of the eye with a normal camera using visible-wavelength images rather than near-infrared images has provoked research interest. However, segmenting noisy sclera areas with images captured on-the-move and at-a-distance has not been extensively investigated. Therefore in this paper, we propose a new method for minimizing the effect of distance on sclera segmentation. In addition, the proposed method involves sclera template rotation alignment and a distance scaling method to minimize the error rates when noisy eye images are introduced. The experimental results using the on-the-move and at-a-distance UBIRIS.v2 database show a significant improvement in term of error rates and accuracy.

____________________________________________ IPV6 Header Compression using a Context-Based Algorithm for Integrating Wireless Sensor

Networks and the Internet of Things

Sameer Alsudany, Said Boussakta and Martin Johnston

Connecting wireless sensor networks(WSNs) to the Internet using the traditional IPV6 protocol is a great challenge due to the short medium access layer frame length of the WSN and large IPV6 and UDP headers. Therefore the Internet Engineering Task Force (IETF) recently formulated a protocol that connects WSNs to the Internet. One of its functions depends on a context table that maps the more frequent Internet address prefixes to several bits identifiers leading to decreasing the number of bytes used by IPV6 address. However, the design of the context table is out of scope of this protocol. This paper proposes an algorithm to manage a dynamic context system in which a context table was designed. Mechanisms for updating, synchronizing and disseminating its contents through the network were implemented to perfect the operation of the system. Simulation results showed the performance of this algorithm compared to the static context system.

____________________________________________ Geometrical Method for Face Recognition

Mahammad Fakhir, Wai Lok Woo, Jonathon Chambers and Satnam Dlay

Pose variance is a particular challenge in face recognition. This problem is part of the grand challenge of recognition variation in pose and camera calibration. Hence, we introduce our novel algorithm based on a geometric method of different pose face recognition that is efficient in handling the range of pose variations within ±60° of rotation. Our approach is to calibrate the camera from a 2D image using fixed robust facial landmarks to ensure a reliable estimation of real dimensions. Therefore, we decompose the image into grayscale before any feature extraction and selection. Our technique then transforms the original image to a full face pose in order to accurately estimate the distance between the eyes. Extensive and systematic experimentation on FERET database shows that our proposed method consistently outperforms single-task-based baselines as well as state-of-the-art methods for the pose problem.

____________________________________________

HARMONIC AND PERCUSSIVE MUSICAL INSTRUMENTS SEPARATION BASED ON

NMF2D

Ahmed Al Tmeme, W. Woo and S. Dlay

In this paper the Harmonic and Percussive musical instruments will be separated by using the two dimensional nonnegative matrix deconvolution (NMF2D). Where both the Harmonic musical instruments and the Percussive musical instruments will be simultaneously modelled by using the NMF2D. The Itakura-Saito (IS) divergence will be used as the cost function for the proposed method, due its scale invariant properties. The proposed algorithm will be used in the under - determined mixture (where the number of mixing channels is less than the number of the musical sources). Finally, experimental results that applied on the SiSEC dataset showed the competence of the proposed algorithm in comparison with other algorithms.

____________________________________________ Stochastically Speech Segregation by the Clustering of Audio Feature

Hasan Kadhim, Lok Woo and Satnam Dlay

To simplify the jobs of speaker diarization and speech separation, at first, speech signal should be segregated to two speech formats, dialog and mixture. This paper describes a new algorithm which achieves that first step efficiently. The algorithm is based on Perceptual Linear Predictive feature extraction, optimized k-means and both top-down & bottom-up scenarios. After extracting features of the observation signal, k-means clusters the statistical properties such as variances of the PDF (histogram) of clustered extracted features. k-means is optimized by discounting the worst pattern of clustering step through doing the k-means procedure twice. The feedback loop is necessary for the guiding of the optimized k-means by exploiting the attributes of ordinary k-means. The results of segregation are excellent. The calculated diarization error rate of outputs are very limited.

Electrical Power

Presentations

____________________________________________ On-line Parameter Estimation and Adaptive Control of Non-Minimum Phase Switch Mode

Power Converters

Ruisheng Li and Matthew Armstrong

Influenced by many internal and external disturbances, varying parameters of passive components is a significant restriction for high quality voltage regulation of Switching Model Power Converters (SMPCs). This research focuses on the efficient online System Identification for a DC-DC boost converter to identify the varied passive component and estimated the new parameters value. Different from buck converter, boost converter has two left half-plane poles (LHP) and one right half-plane (RHP) zero in its mathematical model. The existence of RHP zero of boost converter causes a zero is out of the unit cycle in discrete model which consequent an unstable effect to the system. As a result, system identification for boost converter is more difficult than buck type. The paper will illustrate the RHP zero problem in detail and propose a novel method to resolve this problem.

____________________________________________ Linear Modulate Pole Machine manufacture simplification

Junnan Wang and Nick Baker

Compared to traditional linear machine which the stator winding is distributed around the motion direction, the modulate pole machine (MPM) can be classified into flux transverse machine moreover as each pole for each phase can be analysed individually which be called ‘modulate’. The MPM offers better efficiency, simpler winding structure and higher utilization on magnet material which have been approved elsewhere, however the construct lamination and assembly process are more difficult, in this paper by using the method of combing stator tooth the machine lamination and assembly difficulty can be released which can be regarded as ‘combined three phase-pole’ machine meanwhile the performance (electric force) won’t be reduce reversely increased about 10% moreover by further varying the combined tooth parameters the cogging force and voltage harmonics can be improved as well. This research was approved by using finite element analysis software and will be validated during the lab work.

____________________________________________ Sensorless Torque Control of Induction Motor for EV Application

Ehsan Dehghan-Azad

One of the key components in Electric Vehicle (EV) application is position sensor. Position sensor is responsible for providing speed of electrical machine to commanding control algorithm. Due to harsh environment and vibration, probability of exposure to position sensor failure in EVs is very high. This failure forces EV’s control mechanism to shut down and brings the vehicle to halt mode. In order to increase safety of EV during position sensor failure, this paper proposes sensorless torque control using Indirect Field Oriented Control (IFOC) applied to Induction Motor (IM). The sensorless control technique consists of torque and speed observer. The torque observer takes advantage of closed-loop current and voltage based stator flux observers which are suitable for low and high speed operations, respectively. The torque observer compensates for stator resistance variation and dead time problems. In order to estimate the speed, Phase Lock Loop (PLL) mechanism is employed.

____________________________________________ Sensor-less Induction Motor Drive with Multilevel Converter and Output Filtering

Jamie Lamb

Some applications and operating environments such as downhole drilling in the oil and gas industry demand the use of remote induction machines. A complication that arises with remote machine control comes from long supply cables and square PWM waveforms giving rise to reflected waves. A low pass filter can be connected to the output of an inverter so that a smooth sinusoidal waveform is presented to the machine. Sensor-less vector control with output filter is not a common practice and the impact of filter cut off frequency upon the dynamic response of the system is unclear. Stator voltage knowledge is an essential parameter for MRAS speed estimation and direct measurement is not possible with conventional PWM drives due to the necessary high sampling rate however with output filtering direct measurement of the machine terminal voltage becomes possible. An MRAS speed observer utilising stator voltage detection is presented in this work.

____________________________________________ Effect of winding connection on performance of 6 phase switched reluctance motor

Deng Xu, Barrie Mecrow and Shady Gadoue

In this paper, five winding connection types for a 6 phase switched reluctance motor (SRM) are proposed. By comparing the mutual inductance effect between conducting phases of different winding connection types, optimized decoupling types have been found. In order to compare the performance of different winding connection types, a 6 phase 12/10 poles traditional SRM test rig is employed. Test results of low speed and high speed are presented, long flux-path types have better control performance of current chopping control (CCC) in low speed and angle position control (APC) in high speed.

____________________________________________

Establishing EV charging load flexibility for supporting the power system without impacting

driver usability

Andrew Jenkins

Electric Vehicles (EVs) have been proposed previously to be a form of flexible electrical load (including potentially vehicle to grid generation) that could be controlled to help support distribution networks. This is because they are typically stationary 95% of the time, potentially plugged into the grid and have a relatively large battery on board. This paper proposes an aggregation and control methodology for the grid to consider a number of EVs in a similar way to more established Energy Storage Systems (ESS) allowing existing ESS control algorithms to be utilised. Central to the methodology is the knowledge that the flexibility will only be realised if drivers are willing to use utility controlled charging posts and as such the drivers’ requirements are considered; a minimum amount of energy is guaranteed to be within each vehicle at the time of departure.

____________________________________________ High Voltage High Power Modular Multilevel DC/DC Converter for Off-shore Wind Farm

DC Collection Point

He Liu

This paper presents a new high voltage high power DC/DC converter configuration suitable for off-shore wind farm application. The proposed converter functions as a DC collection point and boosts the wind generators voltage to facilitate the employment of high voltage direct current (HVDC) transmission lines. The proposed converter utilizes the modular multilevel converter (MMC) structure and combined DC/DC converter linked by medium frequency transformer, which leads to lower voltage and current stresses of diode bridge rectifier compared to the conventional DC/DC converters while using relatively smaller transformer. This topology also features modularity, which significantly improves system’s reliability and implementation. The design and the analysis of the proposed converter will be presented in this paper with various operating points. A new control method will be also derived and demonstrated to show the effectiveness of the proposed system.

____________________________________________ Design of Surface Mounted PM Linear Alternator for FPE applications

Aslan Jalal and Nick Baker

The work presents a design methodology for a Surface Mounted Permanent Magnet Linear Alternator (SMPMLA) for use with an External Combustion - Free Piston Engine (EC-FPE). This topic has attracted research interest in the past (2-3) decades as an alternative to the conventional rotary engine in special applications, such as range extender for hybrid vehicles, combined heat power generation into the grid, generation on board spacecraft or use as a standalone power supply. In the literature, individual topologies have been considered throughout research groups worldwide, from which the tubular geometry dominates over other geometries due to its axisymmetric properties, manufacturability, and compactness assuring higher power densities. In this paper, the design of three alternative tubular surface mounted permanent magnet linear machines with modular windings is investigated for the same force capability, where these three topologies have not been specifically compared for the same force capability.

____________________________________________ Torque Improvement of Switched Reluctance Motor by Considering Mutual Coupling Effect

Yang Lu, James Widmer and Richard Martin

The Switched Reluctance Machine (SRM), as a magnet-free electric machine has been witnessed rapidly development during recent years. Due to its low-cost and robust structure, the SRM is a potential candidate for propulsive applications in electric vehicles. However, there are still some drawbacks in the SRM that impede its application. One of the major problem is the lower torque density comparing to the Permanent magnet machine. To enhance the torque output, the extra torque from mutual coupling effects may provide a possible assistance. In this paper, the mutual coupling effects in the conventional SRM will be investigated

and a SRM that may benefit from mutual coupling effects will be described. The static and transient 2D Finite Element analysis result of this SRM will be presented. It will be observed that this SRM could provide a promising torque performance.

____________________________________________ High reliable capacitors embedded in modular multilevel converters

Chenming Zhang

The modular multilevel converters (MMC) is a hot issue in high-power application for its high power and redundancy with low distortions and switching frequency. The reliability issue of the MMC is drawing more attention recently. The reliability contains three aspects: 1) fault diagnosis 2) life-time prediction 3) fault management. The fault diagnosis scheme is the ESR and capacitance estimation by the identification methods based on ripple current and voltage across the sub-module (SM) capacitors. In order to improve the accuracy of the estimation, the voltage balancing algorithm and circulating current control methods are introduced. The validation of proposed methods are verified by the simulation results. The life-time prediction model and future research direction about the fault management are also discussed in this report.

____________________________________________ Health Monitoring Applied to High Power IGBT Modules

Richard Mandeya and Volker Pickert

This paper proposes a novel in-situ health monitoring interface for high voltage high current Insulated Gate Bipolar Transistor (IGBT) modules, also known as high power or multichip IGBT modules. In practice, a multichip IGBT module may continue operating upon the initial single chip failure due to several IGBT chips in parallel. Nevertheless, the IGBT module’s health depreciates with every chip failure, eventually suffering catastrophic failure. In this paper, a new technique is proposed that monitors IGBT module chip failures through a signature between the zero-crossing and threshold voltage of the Gate-Emitter Voltage (VGE) at turn on. In this VGE region before threshold, the IGBT is still in the off-state, such that variations in Collector Current (IC) and Collector-Emitter Voltage (VCE) have negligible influence on the proposed technique. To validate the proposed method, simulation and practical results are presented in the paper.

____________________________________________ A comparison of Magnetic Microstructure for different SmCo Alloys obtained using

Magnetic Force Microscopy

Muhsien Yazid, Glynn Atkinson and Sarah Olsen

This paper describes the use of Magnetic Force Microscopy (MFM) to investigate the domain structure of different sintered SmCo alloys in a thermally demagnetized state, prepared with different processing routes. Observations are made on surfaces perpendicular and parallel to the alignment axis (easy axis). Maze-like magnetic domains and stripe magnetic domains are observed in the form of fine and coarse domains. Interaction domains are formed depends on the material structure. The average domain width in both

directions is determined. The ratio of ϕ┴ to ϕ^(//) was found to be a good indicator for the magnetic performance.

____________________________________________ Design of Electrical Machines with Compressed Windings

Mehmet Kulan, Nick Baker, James Widmer and Simon Lambert

Permanent magnet (PM) electrical machine drives offer significant advantages in terms of torque and power density but there is still room for improvement, especially in increasing slot fill factor to achieve electrically and thermally improved electric machines. Coil pressing is a method that bobbins can be compressed at high pressures by using a punch and die to enhance the slot fill factor. In this research, deterioration of insulation in compressed windings will be investigated by performing quasi-static explicit dynamics finite element simulations and single stress model accelerated life tests. The results obtained from the proposed methods

will be further investigated experimentally to validate the durability of the compressed coils. A crankshaft mounted integrated starter–generator (ISG) machine with pre-pressed stator bobbins is also designed and optimised to verify the advantages of high slot fill factor on the overall machine performance considering electromagnetic and thermal aspects, as a part of the research.

____________________________________________ Large air gap squirrel cage induction machine for a tidal turbine

Liam Naugher, Nick Baker and Glynn Atkinson

The project is to design an electrical generator for application as a tidal turbine. The existing design is of a permanent magnet synchronous generator, which is manufactured by the company OpenHydro. Initially this generator was optimised, and other generator topologies were investigated as alternatives. The results of the optimised design are the benchmark for the comparison of the alternative topologies. The induction machine was chosen for the alternative design due to its simple and robust construction, and the absence of rare earth magnets. An analytical design method was created to provide the initial designs, and these designs were validated using the software MotorSolve before the use of FEA to confirm the designs performance. These designs were then manually optimised using the analytical design method. The design that fulfils the set criteria will be constructed to scale for collection of experimental data for comparison to the simulated results.

____________________________________________ An Electrical Machine with Integrated Drive Filter Components

Mohamed Mohamed

In active power converters supply current filtering is achieved using input filters which are responsible for reducing switching frequency ripple and suppressing voltage transients. An input AC current filter is necessary for grid-connected, three-phase active rectifiers supplying adjustable speed drives. Unfiltered these converters would inject harmonic current distortion onto the supply current and hence inputAC filters are used to mitigate these harmonics. In literature, it was shown that “LCL” filters offer optimum results in power ranges up to hundreds of kilovolt-amperes. In the context of an Integrated Drive (where the machine, power devices and passives are mechanically packaged together in a single unit) this paper will present various options for the three larger filter inductors (one per phase) to be integrated into a motor by sharing the same magnetic circuit producing a single mechanically packaged unit without significant increase in loss and size which in turn achieves higher power density.

____________________________________________ Online Health Monitoring for SiC MOSFET

Xiang Lu and Volker Pickert

Comparative simulation works have been done in regarding the TSEPs (Temperature Sensitive Electrical Parameters) of both Si devices including MOSFET and IGBT and SiC MOSFET. The results show that traditional TSEPs which work well for the Si devices are not quite suitable for the SiC MOSET. This is mainly because the sensitivity of the TSEP of SiC MOSFET is too small to be detected in practical experiment and the shift of the TSEP is not sufficient enough to tell the temperature change. Another difficulty is the dynamic response of the SiC MOSFET is also hard to be observed due to the ultra-fast switching frequency while the device is more vulnerable and sensitive to the parasitic components than the Si devices. In this letter, a new method has been proposed to use signal injection to detect the degradation of the bond wire of SiC MOSFET.

____________________________________________

On the Identifiability of Steady State Induction Machine Models using External

Measurements

Ahmed Alturas, Shady Gadoue, Mohammed Elgendy and Bashar Zahawi

A common practice in induction machine parameter identification techniques is to use external measurements of voltage, current, speed, and/or torque. Using this approach, it is possible to obtain an infinite number of mathematical solutions representing the machine parameters. This paper examines the identifiability of two commonly used induction machine models, namely the T-model and the inverse Γ-model. A novel approach based on the Alternating Conditional Expectation algorithm is employed here for the first time to study the identifiability of the two models. The results obtained from the proposed ACE algorithm show that the parameters of the commonly employed T-model are un-identifiable, unlike the parameters of the inverse Γ-model which are uniquely identifiable from external measurements. The identifiability analysis results are experimentally verified using the measured operating characteristics of a 1.1 kW three-phase induction machine in conjunction with the Levenberg-Marquardt (L-M) algorithm which is developed and applied here for this purpose.

____________________________________________ Novel DC dtection method for Transformer-less Single Phase Grid Connected PV Inverter

Weichi Zhang, Matthew Armstrong and Mohammed Elgendy

Transformer-less, grid connected, photovoltaic inverter systems are becoming increasingly popular due to their reduced volume and high efficiency performance. However, the potential risk of dc current injection into the grid is of significant concern in such systems. Moreover, accurate determination of the dc current content in the inverter output is particularly challenging. This is primarily because the very small dc signals have to be extracted from much larger ac signals, and the measurements can be significantly influenced by noise. In the paper, a Mid-Grounded Low Pass Filter (MGLPF) circuit is proposed which will greatly step down the AC voltage. Most importantly, the small DC component is fully remained in the meantime. A further Digital-Cycle-Average (DCA) algorithm is then applied to accurately extract the DC voltage through inputting the step-down signal in microprocessor. In the simulation, the proposed method shows advantages in both simplicity and accuracy.

____________________________________________ Capacitor voltage estimation in Modular Multilevel Converters using an adaptive observer

Osama Abushafa, Shady Gadoue, Mohamed Dahidah and David Atkinson

Future power grid (i.e. smart grid) requires high power efficiency as well as low cost power suppliers to customers. Modular Multilevel Converter (MMC) suggested being a key element for future connection between power plants and transmission lines because of its futures comparing with traditional converters. Different application can be used for this converter; one of the most promising applications is a high voltage direct current system (HVDC). However, the MMC has some challenges which need to be included in the converter design. Examples of these challenges are: voltage capacitors imbalance, effect of circulating current on the output signals and high number of mandatory sensors. This paper will focus mainly on how to minimise some of voltage transducers. This work proposes a novel adaptive observer based on Kalman filter (KF) to estimate the capacitor voltages of the MMC.

____________________________________________ Material property parameters for structural simulation model of electrical machines

Ruchao Pupadubsin, Andrew Steven, James Widmer and Barrie Mecrow

The accuracy of the structural simulation model is necessary for prediction of each dominant modal frequency of stator vibration in electrical machines. The material properties such as mass density, Poisson's ratio and Young's modulus play an important role of the modal frequencies in the machine structure as well as mechanical shapes and dimensions. Because of changing the properties of material during manufacturing process of the stator lamination core, and vanished windings, the Young's modulus of the stator lamination

core and coil winding is difficult to know the exact values. In contrast, the Young's modulus of solid component parts as motor frame and end-covers can be found from manufacturing data sheet. In this paper, the techniques for the Young's modulus estimation of the stator lamination core and coil winding were presented, and a new semi-finite element technique has also been developed for calculation of the Young's modulus in the lamination core.

____________________________________________ A cascaded transformer-based equalisation converter for series connected battery cells

Huaxia Zhan, Simon Lambert and Volker Pickert

Hybrid electric vehicles (HEVs) and electric vehicles (EVs) have increased in popularity since they use rechargeable battery as energy source instead of petrol, furthermore, help to reduce the release of greenhouse gases. Generally, for applications as an EV, a battery pack insists of hundreds even thousands of batteries is needed to meet voltage and energy capacity requirements. However, every battery cell has unique charging/discharging speed due to their chemical characteristics. This would lead to unbalanced voltage during charging/discharging period among the battery pack, and cause over-charging/over-discharging for certain cells. Therefore, an equalization circuit is quite essential in a battery charging system. This paper proposes a new cascaded multi-winding transformer based equalization circuit, which compares to traditional transformer-based circuits, the structure of transformer has been simplified and much more easier to manufacture, besides, accelerate equalization speed at same time.

____________________________________________ Low Frequency AC Transmission System for Offshore Wind Farm

Jiankai Ma and Mohamed Dahidah

This presentation presents the implementation of Back-to-Back Modular Multilevel Converter in Low Frequency AC Transmission System (LFAC) for offshore wind farm. The LFAC has been compared with other conventional transmission systems, DC and 50Hz AC. The Back-to-Back MMC with half-bridge structure and N+1 topology has been simulated in Matlab. The performance of voltage balancing control in Back-to-Back MMC is studied in steady state, simulation results shows that is highly fast and accurate. As the ultimate goal is to control the power exchanges between two AC grids, it is important to monitor the active and reactive power of the AC grid at each end in LFAC system. In Matlab, by collecting the values of the AC side voltage and DC voltage, it is possible to derive the required controlling signals by using PI controllers. Tuning PI is time consuming but the results illustrated that the system responses quickly and stable.

µSystems

Presentations

____________________________________________ An FPGA implementation of a wavelet based seizure detection filter for real time close loop

epileptic seizure suppression

Lijuan Xia and Patrick Degenaar

An implantable low power PCB Board design based on flash FPGA has been proposed for epileptic seizure detection in this paper. It is a part of the close loop wearable epilepsy treatment prosthesis which triggers optogenetic stimulus to suppress epileptic seizures with halorhodopsin. The proposed PCB Board design consists a pre-amplifier, ADC module, and wavelet filter and threshold detection module. A mathematical model of this proposed wavelet-filter seizure detection algorithm has been validated by matlab and a VHDL

design has been implemented in flash FPGA ProASIC3 Starter kit. The proposed detector has been tested by using cortex Local field potential recording from rats with drug-resistant epilepsy ( ). An average detection delay of 900ms is achieved with a sensitivity of 96% and specificity of 93%.

____________________________________________ An Event-Driven Asynchronous Level-Crossing ADC Based on Charge to Digital Conversion

Austin Juma, Oyinkuro Benafa, Patrick Degenaar and Alex Yakovlev

We proposes an event driven asynchronous Level Crossing ADC, based on Charge to Digital conversion that exhibits a power consumption profile proportional to its input signal’s rate of change. The ADC utilizes a fixed voltage window, level crossing slope detector to trigger a local Charge to Digital converter that samples and converts the input signal at a non-uniform rate. The circuit was realized and simulated in a 0.35um technology process, achieving a SNDR of 41.26dB while consuming 48.6uW for a 2kHz pure sine-wave input.

____________________________________________ Wireless Data and Power Transfer of an Optogenetic Implantable Visual Cortex Stimulator

Nabeel Fattah, Patrick Degenaar, Graeme Chester and Danil Sokolov

In this paper, the wireless data and power transfer for a novel optogenetic visual cortex implant system was demonstrated by using pork tissue mimic in-vitro at the ISM 2.4 GHz and 13.5 MHz frequency band respectively. The observed data rate was 120 kbps with no loss in data for up to a thickness of 35 mm in both water & pork. To increase the power level of the implant a Class E power amplifier is separately designed and simulated for the transmitter end and has an output power of around 223 mW with an efficiency of 81.83%. The transferred power at the receiver was measured to be 66.80 mW for the pork tissue medium considering a distance of 5 mm between the transmitter and the receiver coils, with a coupling coefficient of ~0.8. This serves the power requirement of the visual cortex implant.

____________________________________________ Towards a Systematic and Automated Approach in the Design of Processor Instruction Sets

Alessandro de Gennaro and Paulius Stankaitis

Adopting a systematic approach for the design of a processor instruction set is instrumental for tackling the complexity, which rules most of modern processors. We present a tool-chain which follows the designer through all the phases of the design, from the specification of instructions to the hardware synthesis of a microcontroller. The flow is also meant to simplify the understanding of the Instruction Set Architecture (ISA) reference manuals. Often, these documents are semi-formal, hard to read and fully understand. We believe that designers will benefit from a visual graph-based model, automatically derived from the ISA specification, and customisable to fit different needs. Some of the tools have already been developed and tested on ARMv6-M architecture, others yet need to be fully implemented. The design flow will be integrated inside the Workcraft framework. We also compare the presented approach with the others available in the literature.

____________________________________________ Wideband Dynamic Voltage Sensing Mechanism for EH Systems

Kaiyuan Gao, Yuqing Xu, Delong Shang, Fei Xia and Alex Yakovlev

In Energy Harvesting (EH) scenarios, the 'survival zone' pertains to the state of power supply with insufficient energy to provide a nominal and stable Vdd. In this situation the system Vdd tends to be low and to vary over a wide band. Benefits can be had if the system can already function to some degree under survival zone conditions. Such functionalities may include providing control to improve the efficiency of power processing units and starting the computation load for light but crucial survival-related tasks. Knowledge of the Vdd is often indispensable for running these types of survival zone functionalities. A novel low-power voltage sensing scheme for EH based electronic systems is proposed to function in the survival zone to provide this

vital Vdd information. The method is derived by combining voltage controlled delays and simple circuits to implement time comparison.

____________________________________________ Study of Power-Aware Performance Adaptation in Embedded Heterogeneous Multi-Core

Systems

Ali Aalsaud, Rishad Shafik, Fei Xia and Alex Yakovlev

Modern embedded systems consist of heterogeneous computing resources with diverse energy and performance tradeoffs. This is because applications with varying workloads exercise the underlying hardware resources differently. As a result, determining the most energy-efficient system configuration (i.e. the number of parallel threads, the operating frequencies, etc.) tailored for each kind of workload (CPU- or memory-intensive or both) is extremely challenging. In this paper, a comprehensive study is carrying out to investigate the trade-offs under different system configurations using an Odroid XU-3 heterogeneous platform with a number of PARSEC benchmark applications. To effectively determine energy-efficiency, a power normalized performance metric is used, expressed in terms of instructions per second (IPS) per unit power (watt). Using this metric, we show that with increasing number of threads CPU-intensive applications show higher IPS/watt compared to memory-intensive applications. Furthermore, we also demonstrate that increasing frequency affects to CPU performance normalized power.

____________________________________________ Investigation into Power Normalised Speedup Models for Energy-Efficient Many-Core

Computing

Mohammed Al-Hayanni, Fie Xia, Alex Yakovlev and Rishad Shafik

Continued technology scaling has enabled seamless integration of many interconnected cores on a single silicon chip. The emergence of such integration has facilitated unprecedented performance improvement, which has been defined by a number of speedup models. Amdahl’s law is a major speedup model that estimates the maximum performance improvement (in terms of latency) with fixed workloads in parallel and serial parts. Following Amdahl’s law, a number of variant models have also been proposed over the years. Among these Gustafson’s law is a popular model that introduces variable workloads and estimates fixed time speedup (in terms of throughput). Sun and Li combined the above two models into one considering the memory-bounded situation with variable workloads. These models are further extended by the Hill-Marty model through considerations of homogenous and heterogeneous core configurations. This paper investigates into these models and comparatively analyses them through novel insights using a power normalised performance metric for both homogenous and heterogeneous configurations. A comprehensive analysis is carried out with different ratios of parallel and sequential workloads to identify the most energy-efficient system configuration based on these models.

____________________________________________ Compositional design of asynchronous circuits from behavioural concepts

Jonny Beaumont, Andrey Mokhov, Danil Sokolov and Alex Yakovlev

Asynchronous circuits can be useful in many applications, however, they are yet to be widely used in industry. The main reason for this is a steep learning curve for concurrency models, such Signal Transition Graphs, that are developed by the academic community for specification and synthesis of asynchronous circuits. In this paper we introduce a compositional design flow for asynchronous circuits using concepts – a set of formalised descriptions for system requirements. Our aim is to simplify the process of capturing system requirements in the form of a formal specification, and promote the concepts as a means for design reuse. The proposed design flow is applied to the development of an asynchronous buck converter.

____________________________________________ ASCA: Approximate adder with speculated parts and configurable accuracy

Khaled Al-Maaitah

Approximate computing is an emerging paradigm that exploits the error tolerance in some application like Multimedia and data mining for more efficiency in terms of speed, area and energy. However, the key challenge is how to trade off gracefully the power and accuracy in order to keep accepted outputs. On the other hand, speculation methods are used in main arithmetic units like adders and multipliers to produce high speed designs by speculating carry-in values; however, these designs propose rare probability of error occurrence. In this paper, a new hybrid adder’s design is proposed, which shows new techniques for segmentation and carry in prediction combined with light weight error detection and correction (EDC) circuit. In addition, a novel technique for controlling the adder accuracy is proposed using related speculative adder signals within each segmented block; this technique uses the correlation of distribution of error and a group of significant bits in input data. Simulation results show speed increasing, reduction of power consumption with lower overhead of area.

____________________________________________ Design interconnects driver in ultra-low power

Mohammed Al-Daloo, Alex Yakovlev and Charalampos Tsimenidis

For many years ago the power was neglected and the main concentrated on performance, cost, area and reliability, but this change by emerging applications demands low power and not a high performance. These applications require less weight, longer energy source life, and no cooling system. Since reduce power consumption could achieve that the trend to have circuits have ultra-low power budget is seemed to be the solution. Therefore, proposed work has focused on a particular type of interconnect drivers based on voltage boosting (via charge pumping) technique to drive a long interconnect under the ULP regime using subthreshold. The bootstrap driver consists of two stages, the first one is a normal driver with PMOS and NMOS transistors that are derived by the enhancing voltage circuit (stage 2) which is duty to generate a voltage, theoretically, from -Vdd for pulling up to 2Vdd for pulling down.

____________________________________________ Low Power Capacitance to Digital Conversion

Yuqing Xu, Delong Shang, Kaiyuan Gao, Fei Xia and Alex Yakovlev

Capacitance sensors are widely used for sensing physical parameters. Conventional capacitance to digital methods use complex analog ADC techniques which are power hungry. Recently a fully digital solution was proposed with improved power consumption. This paper describes a number of problems in that solution, analyzes these problems, and proposes a new design free of these problems. The new method achieves the same accuracy with less than half the circuit size, and 17% and 35% savings on power and energy consumption.

____________________________________________ A Workflow for the Design of Mixed-signal Systems with Asynchronous Control

Vladimir Dubikhin, Andrew Fisher, Danil Sokolov, Chris Myers and Alex Yakovlev

While numerous tools have been developed for automation and verification of digital design, analogue tool development has not kept pace. To cope with this problem analogue designers have turned to using digital alternatives whenever possible. Existing methods for digital design are based on synchronous circuits, which results in suboptimal solutions for mixed-signal systems. Asynchronous circuits can provide greater robustness, reactivity, and power efficiency, however, due to the lack of necessary computer-aided design tools, engineers have to rely on ad hoc development approaches and use extensive simulation to prove correctness of their designs. Recent research has addressed both problems in the design of analogue/mixed-signal(AMS) systems. The tool WORKCRAFT aims to provide formal methods for specification and synthesis of asynchronous circuits. Formal verification of AMS circuits is performed by the tool LEMA. This paper describes a workflow that leverages both of these tools to design mixed-signal circuits with asynchronous digital control.

____________________________________________ Analytical technique to assess digital circuit reliability

Mohamed Abufalgha, Alex Bystrov and Alex Yakovlev

Reliability of integrated circuits and energy consumption is considered as a critical challenge facing the chip designers. In nanotechnology design, circuit reliability becomes main part in the trade-off concept. Reliability, energy consumption, and performance trade-off has been studied in this paper, which considered as a next step of Performance and voltage Dynamic scaling. We introduced analytical method to evaluate the reliability of a circuit, and how the reliability improves according to the change of supply voltage, operating frequency, and energy consumption. It is a different method from the previous methods, where Monte Carlo simulation software has been used. The relation between the reliability and the position of the neutron strike is studied to find the effect of attenuation on the generated glitch. The proposed method has been applied on a chain of inverters, which is considered as a single path circuit.

____________________________________________ Initial ideas about significance-driven approximate multiplication

Issa Qiqieh

There has been an increasing interest in approximate computing to exploit the inherent resilience in a broad spectrum of hardware implementations by relaxing the need for completely precise or totally deterministic operations. Therefore, approximate computing trades off output quality for achieving much lower power consumption, shorter run times, and often smaller area than their exact equivalents. In this paper, we describe approaches and results in our work on approximate arithmetic. We propose a new significance-driven multiplier architecture for error-resilient designs. Since our aim is to make approximate multiplier fast, we present a novel Carry-in Prediction Logic that significantly reduces the horizontal critical path. The proposed multiplication reduces the latency and increases the throughput of an accurate multiplier. Our design is based on a new algorithm for approximate multiplication where an efficient precomputation logic is employed to increase its throughput in conjunction with allowing greater pipeline level parallelism.

Emerging Technology and Materials

Presentations

____________________________________________ FABRICATION AND CHARACTERISATION OF 4H-SiC SCHOTTKY DIODE FOR

HIGH VOLTAGE TESTING

Nurul Mohamed, Nick Wright and Alton Horsfall

There is increasing interest in the development of radiation hard detector materials with the capability to discriminate between different types of radiation. Since high-energy radiation and low-charged particles stop at higher range in detector material, high bias voltage is required to increase the depletion region width. Characteristics of different Schottky contact areas have been analysed using Cheung’s method prior to high voltage testing. The values of series resistance, RS obtained from two different plots agree within 5.5% and scales with contact area. Annealing Ti/Ni metal contacts at 660°C/700°C resulted in the formation of nickel silicide with barrier heights, Φb in the range of 1.14-1.75eV and ideality factor, n values between 1.0-1.5. The breakdown voltage of the diodes exceeded the depletion voltage of the epilayer and electrical characteristics

at room temperature demonstrate leakage currents as low as 0.4pA (-200V). Therefore, these devices are ideally suited for the realisation of radiation detectors.

____________________________________________ Plasmon activated hot carrier emssion for ohmic contacts to n-type germanium

Srinivas Ganti, Peter King and Anthony O'Neill

This paper presents a unique contact materials system that enables surface plasmon modes to provoke hot carrier emission. Ohmic transport is demonstrated on low doped n-type germanium. Evidence of Zener breakdown is also reported at ~ -0.6 V in the reverse bias at room temperature. Cryogenic I-V data shows that this breakdown onsets at even smaller voltages at liquid nitrogen temperatures in the reverse bias; enabling the use of germanium based CMOS technology in harsh environments.

____________________________________________ Blue-shifted Optical Properties of Porous SiC Prepared by Anodic Electrochemical Etching

and Ultrasonication of 4H-SiC Substrate

Marzaini Rashid, Benjamin Horrocks, Noel Healy, Jonathon Goss and Alton Horsfall

Bulk silicon carbide (SiC) has been known as a technologically important material for applications in extreme environments owing to its high radiation and chemical tolerance, high thermal conductivity and high critical electric field. Despite its superior properties, SiC in its bulk form is an indirect bandgap material similar to silicon. Room temperature emission in porous Si (P-Si) has initiated interest in porous SiC (P-SiC). The large surface area and enhanced optical properties of P-SiC have found use in preparing SiC quantum dots with potential application as biomarkers, high temperature resistant gas sensors and ultraviolet photodetectors. In this work, bulk n-type 4H-SiC substrate was anodically etched in HF/ethanol solution followed by sonication. Characterisation by x-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence (PL), ultraviolet-visible spectroscopy (UV-ViS) and Raman spectroscopy showed enhanced and blue-shifted optical properties of crystalline P-SiC that are promising for use in novel optoelectronic applications.

____________________________________________ Impact of interstitial iron at extended defects on silicon solar cell performance

Oras Al-Ani, Jonathan Goss, Nick Cowern, Patrick Briddon and Mark Rayson First-principles quantum-chemical simulations are combined with TCAD device modelling to examine the silicon properties with the EDs before and after segregating iron atom impurities, as an attempt to balance interoperation of the advantageous and disadvantageous properties of these defects and impurities on the performance of solar cells. The optical absorption and carrier generation are considered as function of iron concentration. Segregation of diffusing iron at these EDs has a clear impact on device characteristics, but non-radiative recombination processes and carrier traps due to iron have potential impact on device efficiency at these regions. The results show that Fe-impurity has trivial impact on the open-circuit voltage and short-circuit current of solar cell. However, it significantly influence the fill factor by adding series resistance, which in turn degrade the efficiency.

____________________________________________ A First Principles Study Of The Vacancy-Hydrogen Defect In Diamond

Chloe Peaker

Diamond is well known for its superlative properties, for example its high carrier mobilities (µe=4500cm2V-1s-1 cf. Si µe=1450cm2V-1s-1) which are desirable for fast-response and high-frequency electronic devices. Diamonds high thermal conductivity of 24Wcm-1K-1 (cf. Si=1.5Wcm-1K-1) can also be utilised to out-perform conventional materials in areas such as power-electronics, where large amounts of heat are generated.

Defects may be introduced accidentally or intentionally during the manufacturing process of diamond and they are found in natural diamond too. As defects influence the electrical and optical properties, it is imperative to gain an understanding of their properties in order to successfully exploit the material. Synthetic diamond grown from the gas phase is known to incorporate both hydrogen and lattice defects. One example of a grown-in defect is the vacancy-hydrogen complex which compensates donors. The aim of the project is to employ density-functional theory, to accurately determine experimentally observable properties of the vacancy-hydrogen defect.

____________________________________________ Analysis of embedded nickel nanoparticles (NiNP)

Sherko Ghaderi, Sarah Olsen and Lidija Siller Nickel nanoparticles (NiNP) embedded in silica aerogels has a variety of applications including thermoelectrics, carbon capture and surface enhancement techniques of Raman spectroscopy. In this paper the impact of the density of NiNP on the key parameters affecting thermoelectric properties are characterised. In particular, the thermal conductivity and electrical conductivity are analysed as the density of NiNP is increased from 0 to 700ppm. We have used scanning thermal microscopy (SThM) to examine the thermal conductivity and four-probe techniques to measure electrical conductivity of the bulk silica aerogel embedded with NiNP. Initial results suggest that utilising an increased density of NiNP could yield promising thermoelectric properties, as the conductivity is shown to increase with NP density while the thermal conductivity remains constant.

Abstracts ____________________________________________

Communications, Sensors, Signal & Information Processing

Poster

____________________________________________

Distributed Alamouti Relay Network Using Space Time Code

Fahad Alsifinay

Cooperative communications allow improving the capacity and/or expanding the coverage of wireless communication networks. Distributed space time code consists in using space time coding in cooperative relay networks. In this work, we compare the point-to-point and distributed Alamouti schemes in terms of error probability. In particular, we provide the signal model and describe the Alamouti scheme for both point-to-point and cooperative communications. We assume amplify-and-forward relaying protocol and half-duplex transmission mode. Simulation results show that both schemes achieve full diversity. However, the point-to-point Alamouti scheme provides better error probability compared to its distributed counterpart.

____________________________________________ Image Retrieval Using Artificial Intelligence Methods

Hayfaa Hussein, Jonathon Chambers and Mohsen Naqvi

In this work we will focus upon content-based image retrieval systems particularly containing facial expressions. Content-based image retrieval systems play a significant role in many application areas such as satellite images data, diagnostic images data, video content and general consumer use. There is an imperative demand for a system based on the image content to store spontaneous images efficiently and provide faster retrieval. Initially, image enhancement will be studied to improve the quality of a face image. In addition, this work proposes two approaches for analysis: first, spontaneous facial expression will be investigated in term of segmentation and feature extraction effectively to describe expressions. Second, facial recognition methods will be applied to publically available data sets such as the Jaffe database. Finally, facial expression exploiting eigenfaces using by PCA (principle component analysis) will be studied. The aim will be to enhance the state-of-the-art in the field.

____________________________________________ Multimodal Behavioural Signal Processing With Application in Assisted Living

Zeyu Fu, Jonathon Chambers and Mohsen Naqvi

This project will focus upon the design, development and analysis of new algorithmic solutions for processing multimodal signals to aid in assisted living. It is effectively combining audio and visual information to perform human tracking in an enclosed environment. Multimodal tracking could be part of a system to monitor the wellbeing of both an elderly person and a carer, having the advantage that only ambient sensors are employed thereby not encumbering an individual with wearable devices.It is necessary to investigate the established single modality tracking schemes such as Kalman filtering, extended Kalman filtering, together with particle and probability hypothesis density (PHD) filtering. Further research will concentrate on the Multimodal and

Multi-Target tracking, aiming to solve the challenging problems of Non-linearity model, Non-Gaussian distribution and the occlusion and varying lighting conditions in home environment. Tracking performance will be examined by using objective performance measures and suitability for real-time processing.

____________________________________________ Cyclic Prefix-Based Relay Selection for Alamouti OFDM Amplify-and-Forward Relay

Network

Mahmoud Alageli, Jonathon Chambers and Aissa Ikhlef

In this work, we investigate relay selection in asynchronous multi-relay network for frequency selective channels. We consider distributed Alamouti space-time coding and amplify-and-forward relaying, where orthogonal frequency division multiplexing (OFDM) is implemented with adaptive cyclic prefix (CP) to deal with the channels frequency selectivity and timing errors. Optimal and suboptimal relay selection and joint relay-subcarrier selection schemes have been proposed based on two selection criteria. The first criterion uses the end-to-end signal-to-noise ratio (SNR) and the second one uses the effective capacity which is a function of both the SNR and the CP. Simulation results reveal that the optimal relay selection based on effective capacity performs better in terms of outage performance compared to the selection when considering the SNR alone. Furthermore, for joint relay-subcarrier selection, it is shown that no significant improvement is attained by using the criterion based on the effective capacity compared to that based on SNR.

____________________________________________ Multimodal Processing Based Algorithms for Applications in Healthcare Systems

Yang Sun, Mohsen Naqvi and Jonathon Chambers

Providing the assisted living systems within smart home environments for growing elder population will be one of the future challenges. Multimodal signal and information processing can provide robust solutions to the problem. In this work, audio-video modalities will be exploited for automatic fall detection systems. This research will be in algorithmic prospective and major focus will be on audio processing. In a home environment, there could be different type of audio signals from people, television, etc. The observed audio signals will be mixed with noise. Blind source separation (BSS) is one of the significant methods by the signal processing community to separate the mixed signals. The methods in BSS are mainly based on statistical signal processing. Robust solutions to separate the sources at relatively large reverberation time (RT60) are still missing; which is the immediate target of the research. The proposed algorithms will be evaluated on real data sets.

____________________________________________ Novel Cooperative Wireless Sensor Networks for Structural Health Monitoring

Chaoqing Tang and Guiyun Tian

This research aims to find secure, reliable, high speed and low energy consumption communication solution for Wireless Sensor Networks (WSN). New lightweight encryption method or physical layer solution will be adopted to increase security performance, and novel virtual muti-input multi-output scheme aiming at increasing the channel capacity and compressing the energy consumption will be proposed. Meanwhile, this research will apply methods like compressive sensing and optimization theory to remove redundant data, thus cutting down transmitting overhead and improving the system energy efficiency. The proposed scheme will verified by both prototype system and computer simulation. The fruits of this project can offer a more reliable solution for problems such as the data loss, security concern and low transmitting rate of WSN in wireless monitoring systems.

____________________________________________

Security protocols for monitoring system based on The Internet of Things

Yachao Ran and Guiyun Tian

The Internet of Things (IoT) utilizes series of techniques to connect smart objects or "things" together. The concept of IoT involves information gathering, data transmission, data storage and processing which all requires security solutions. The research studies in reviews of cryptography, security protocols and approaches, implementation and applications of IoT and aims to identify challenge and novelty. Deliver a system or protocol with novelty to resolve remaining security issues such as anonymous, privacy and authentication.Methodology involves cryptography algorithms such as ECC, symmetric algorithms such as AES. As communication security combine with resource limitation is one of the major concern of IoT systems, the outcomes of the research include providing optimized protocol to withstand series of attacks,and security solutions to certain IoT monitoring architectures with relative low energy consumption.

____________________________________________ Enhancing Electromagnetic Acoustic Transducer (EMAT) for Pipeline Non-destructive

Testing

Denis Ijike Ona and Gui Yun Tian

The performance of Electromagnetic Acoustic Transducer (EMAT) in long-range Non-destructive Testing as compared to other sensing techniques calls for its development for pipeline inspection. The magnetostrictive Patch transducer (MPT) type of EMAT is capable of generating high powered torsional wave modes which is difficult or cost-ineffective with other sensing systems. However, MPT has challenges of generating high frequency waves at megahertz frequencies and of providing uniform Magnetic field in the patch. This study proposes the enhancement of the MPT by development of Coil configuration techniques and parameter optimisation to compensate for the challenges of MPT while keeping its capabilities.

____________________________________________ Physical layer security with error-correcting codes

Huan Cao and Martin Johnston

As wireless networks play an extremely important role in civil and military networks, security has become an important topic. Most widely used security methods are at the upper layers of a wireless network, but an alternative method of ensuring secure communication is physical layer security, which is a hot topic. The primary aim of physical layer security is to ensure that confidential messages can be transmitted through the wireless medium without being intercepted by eavesdroppers. It has recently been shown that error-correcting codes play an important role in physical layer security and in this project, the design of binary and non-binary codes with physical layer security will be investigated for a variety of different channel models comprising legitimate users and eavesdroppers to strengthen the security of wireless communications.

____________________________________________ XG-FAST: Evolving the Copper Access

Israa Ali, Charalampos Tsimenidis and Martin Johnston

Recently, the fourth generation broadband technology (4GBB), abbreviated as G.fast, demonstrated data rate up to 1 Gbps over length loop up to 250 meters. XG-FAST dubbed fifth generation broadband technology is currently finalized by ITU to succeed G.fast. This technology aims to increase bit rate to 10 Gbps over shorten copper length loop up to 30 meters. This PhD project will focus on the concept of XG-FAST technology by utilizing bonding and phantom transmission modes over short loop lengths up to 30 meters and multiple copper twisted-pair cables. XG-FAST uses an increased frequency range, up to 500 MHz with DMT modulation and concatenated Reed-Solomon (RS) code and trellis code modulation for forward error correction with an interleaver in between. Vectoring techniques will also be considered to mitigate cross-talk cancellation and improve throughput along with state-of-the-art channel coding methods.

____________________________________________ Transceiver Framework for Ultra Low Energy Communications

Ahmad Abdulfattah

The remote monitoring of human body functionalities has emerged rapidly in recent years due to the limitations of hospital resources. Recent advances suggest the Body Sensor Nodes (BSNs) to be one of the solutions in healthcare domain. BSNs enable continuous monitoring which can support medical personnel to prevent and diagnose the illnesses such as heart attack. However, BSNs need continuous power sources to maintain efficient and long-term monitoring. Therefore, conventional batteries are not feasible for such applications due to their fast energy decay and short lifespan. Due to these limitations, there is an increased need for energy harvesting techniques to power the body sensor nodes with long-term energy. In this research, a transceiver framework design is proposed and will be verified for ultra-low energy communication. New chirp-based modulations schemes will be designed under the assumption of non-constant power supply voltage operation and their performance will be evaluated using hardware implementations.

____________________________________________ Software defined radio employing a multi-sensor data fusion approach for safe and secure

vehicle-to-vehicle communications

Jiachen Yin, Rajesh Tiwari and Martin Johnston The major objectives of efficient intelligent traffic systems (ITS) are to improve road users’ safety

and ease traffic congestion. One of the important parameters for efficient ITS, is to establish

communication between vehicles (V2V), infrastructures (V2I) or any other device (V2X). In order

to avoid accidents, the vehicle’s precise position information needs to be shared with other vehicles

within a stringent time and distance. Precise positioning information is critically important to

identify each vehicle’s location in order to avoid vehicular collision.

In this study, we discuss the effects of signal blockage or multipath fading on radio propagation

which degrades the positional information. To mitigate these conditions, a data fusion solution

combining a GPS software receiver, inertial navigation system (INS) LiDAR sensors and a Wi-Fi

receiver will be developed in order to improve the localization for weak GPS signal strength or

completer loss of GPS lock.

Electrical Power

Poster

____________________________________________ Incorporating Asset Management into Power System Operations

Ilias Sarantakos, Pádraig Lyons and Phil Taylor The privatization of the UK electrical power industry in recent years and ageing power equipment in distribution networks have pushed utilities to consider more effective use of their financial resources. That means that the utility companies have to find an optimum balance between their capital as well as operational expenditure and quality of supply. Reducing costs while preserving high network reliability has become much harder nowadays due to increased renewable and distributed generation (DG) along with their associated power output variability and the increasingly old power system components. At present, the situation is that power system operations and asset management actions do not take into account each other. All the aforementioned aspects indicate the significance of coordinating asset management and real-time

operations. This research work will try to bring together these two fields in order to achieve a better outcome on the balance between cost and supply quality.

____________________________________________ Coordinated Control of Hybrid Energy Storage Systems at Distribution Networks

Stalin Munoz, Haris Patsios and Phil Taylor Energy storage within the smart grid concept might be considered as an attractive way for addressing the operational challenges of the grid caused by the continuous growth of energy demand and the increasing penetration of renewables [1, 2, 3]. There are many different types of energy storage devices with a wide range of characteristics and constraints regarding energy capacity, response time and power output. Hybrid systems comprising of two or more energy storage technologies have the potential of combining the individual advantages of different storage devices without presenting any of their drawbacks [4]. The ongoing research will come up with coordinated control techniques for optimizing the operation of grid-connected hybrid systems and expand the number of services that can be provided to the grid. These control techniques will consider multiple objectives (such as peak shaving and frequency control), multiple stakeholders and multiple constraints (e.g. aging).

____________________________________________ Power System Research for improved life and performance

David Mecrow, Glynn Atkinson and Matthew Armstrong One major concern when buying a product is its usable life and the length of the manufacturer's warranty. Due to the extended high speed operation of Dyson machines, the first failure point is most often the bearings. Various methods of decreasing the wear on the bearings as well as more durable or wear tolerant bearings will be discussed. Integration of the new bearing systems into the existing products will be considered, along with the management and optimisation of cost and effective life increase. Any new system must meet the dynamic requirements of the intended products to ensure safe operation and that product quality is not compromised. The benefits and suitability of ceramic rolling element bearings, fluid bearings, magnetic bearings and others will be analysed and compared to provide a general, cost effective solution for increasing the life span of all Dyson products.

____________________________________________ Transverse flux machines for multi mega watt renewable energy generation

Mohammad Raihan Renewable energy converters for wind and wave energy place very specific and unique requirements on electrical generators. Their lower speed of operation has led to the inclusion of gearboxes to step up the speed. Gearboxes have the undesirable maintenance requirement that creates growing trend for direct drive motors. Several commercially available wind turbines use direct drive surface mounted PM machines with a high magnet mass – which has economic and constructional implications. Increasing generator radius is one method of reducing the magnet mass, but constructional worries become worse. Alternative method is replacing conventional electrical machines and investigate transverse flux machines which has superior torque and power density. Whilst theoretically very attractive, the transverse flux machine has unique structure which may be difficult to assemble at full scale. This thesis will use analytical and simulation techniques to investigate the design and build a transverse flux machines for multi-megawatt renewable energy generation.

____________________________________________ Research on heat dissipation and cooling system of permanet magnet synchronous machines

Yaohui Gai, James Widmer and Mohammad Kimiabeigi Permanent Magnet Synchronous Motor (PMSM) will inevitably lead to poor thermal environment heat production or more problem due to its high power, high speed but small installation space. The high temperature of motor will cause a hidden damage in the electric vehicles. In order to avoid such problems.

To accurately predict the internal motor temperature distribution to ensure the safe operation of motor stability is very important. The research contents are about influencing factors of loss, reduce loss method, the key issues about loss of in-wheel motor, how driving part influences loss. Cooling pattern design, correction about water-cooled heat release coefficient correction, winding equivalent model. The factors influencing temperature field simulation, the temperature distribution of PMSM under different conditions. The motor also be cooling under different coolants, for example oil or hybrid water / air approaches. The analysis of heat transfer through computational fluid dynamics.

____________________________________________ Fault torlerant induction machine

Fangbo Liu, Barrie Mecrow and Richard Martin Induction machines are the commonest form of electrical machine and are used for a large variety of traction and industrial applications. There are an increasing number of cases in which very high reliability of the machine and associated power converter is required. For this reason the introduction of fault tolerance is necessary. Fault tolerance in permanent magnet and reluctance machines has been extensively explored, but there has been far less attention to induction motors in this context. The commonest manner in which fault tolerance can be introduced is by splitting the machine into a series of circumferential segments, with each isolated magnetically and electrically from its neighbours. Induction machines pose particular problems, including coupling of adjacent segments through the rotor; and large impact upon performance due to discontinuities in the magnetic field. This work is examining how fault tolerance can be successfully introduced to induction motors for the first time.

____________________________________________ Fault Tolerant Power Steering Systems

Barrie Mecrow and Ari Al-Jaf Driverless vehicles are likely to become mainstream alternatives to conventional vehicles over the next 20 years. The biggest barrier to overcome is that of safety. Very high levels of reliability are needed because there is no immediate backup from a human driver. Central to this is the need for very high reliability in the steering mechanism. In this work, sponsored by ZF TRW, an interior permanent magnet motor is investigated to ascertain its ability to survive faults. Different connection mechanisms and winding arrangements are investigated for an existing motor that is designed by ZF TRW. It is shown that some winding connections create better fault tolerant capability, due to reduced mutual coupling between coils, however account must also be taken of any degradation of torque quality resulting from increased torque ripple following faults.

____________________________________________ Lifetime enhancement for power electronic devices

Yerasimos Yerasimou Power semiconductor devices suffer from thermo-mechanical stress that consequently leads to faults such as bond wire lift-off or solder joint fatigue. These failures are generated by the different expansions of the materials that construct a power module. That is, because each material has its own thermal expansion coefficient (CTE) and each material experiences fluctuating temperatures caused by the chip losses. In order to reduce the mechanical stress the temperature of the power chip should be kept constant. This project is developing a technique how to achieve a constant chip temperature by actively cooling the baseplate of the power module. A new unique active cooling adapter has been developed and is presented here. Results show that the lifetime of the power module can be increased by a factor of 2.

____________________________________________ Design of an adaptive proportional multi resonant controller for grid connected PV inverter

systems

Hamza Khalfalla

The proportional resonant controller (PR) implemented in PV grid connected PV inverter systems is known of its advantageous over the conventional proportional integral (PI) controller when regulating sinusoidal waveforms. These advantages are highlighted because PR controller provides an infinite gain at the fundamental frequency so the steady state error can be eliminated. Another advantage is the possibility of cascading a low order harmonic compensation (HC) without affecting the system dynamics. However, certain drawbacks are associated with PR+HC controller like the sensitivity to grid operating condition such as frequency and grid impedance variation. This poster discusses the design of an adaptive PR controller to improve the controller performance under such variation by exploiting the grid information into the controller design. The proposed solution makes the use of the grid information for controller tuning.

µSystems

Poster

____________________________________________ A Scalability Analysis of Embedded System Applications

Dave Burke and Rishad Shafik As an introduction to a research project investigating the structure of future designs for the Internet of Things (IoT), it was decided to investigate and categorise existing designs, score their Device Technology makeup and give an indication of scores for Power consumption, Performance and Reliability. During this analysis further parameters were added to show Maintainability, Sustainability and Relative Lifetime Cost. The results of this analysis will be presented.

____________________________________________ Energy Efficiency and Scalability Analyses of Concurrent Applications in Linux-based

Multicore Systems

Matthew Travers, Rishad Shafik, Fei Xia and Alex Yakovlev

Modern multicore operating systems, such as Linux, typically execute a number of parallel applications concurrently. These applications are characterised by their variations in the way they exercise the computation and memory resources. This paper aims to investigate the impact of such variations on the overall energy consumption and performance trade-offs. To analyse the trade-offs, three benchmark applications have been chosen with different characteristics - memory intensive, CPU intensive and a mixture of both. These applications are concurrently executed with varied combinations with an aim to also identify the scalability of the system in terms of the number of concurrent applications executed within a given power budget. Underpinning this study, a scalable and energy-efficient concurrency model will be developed for current and future generations of multicore systems.

____________________________________________ Physical Unclonable Function cryptocore for Internet of Things applications

Konstantinos Goutsos Embedded devices in various forms are increasingly becoming parts of everyday life, constituting the Internet of Things(IoT). As IoT applications are beginning to gather and process critical data, the rising importance of the security of such networks is evident. Physical Unclonable Functions(PUF) provide a cost-efficient and highly secure way to enhance many security aspects of embedded devices, including uniquely identifying a device, generating and storing cryptography keys and secure storage. The main aim of this project is to develop methods and perform case studies for using PUFs in IoT scenarios and enhancing device identification, secure enrollment and other security functions while requiring minimal configuration which can be provided out-of-box by the manufacturer. The development of a demonstration application will also

be undertaken and a strong relationship with commercial products and platforms will be built, including the open-source IoT platform DeviceHive.

____________________________________________ Enhancing SRAM Physically Unclonable Functions by Embracing Metastability and

Stochastic Analysis

Michael Walker and Alex Bystrov The infrastructure of embedded devices is ever-growing and our dependence upon them is ever-increasing. However, electronic devices are vulnerable to many security threats and strengthened cryptographic primitives provide increased security, especially in the areas of anti-counterfeiting and key management. Physically Unclonable Functions are a topic of active research, analogous to fingerprints for electronics. They potentially offer low-cost, automated provision of authentication and key generation. One type, the SRAM-PUF, is an attractive option to designers, yet currently has known technical limitations. In our work we seek to find techniques to improve upon the SRAM-PUF. Current techniques treat the effects of noise on authentication responses as problems to be mitigated. We examine the effects of noise sources on SRAM behaviour for use in modelling and stochastically predicting errors. This can be utilised to enhance unclonability and cryptographic strength. From this new SRAM based cryptographic primitives can be developed with improved security features.

Emerging Technology and Materials

Poster

____________________________________________ Heterojunctions of Two-Dimensional Materials

Johannes Gausden The study of two-dimensional materials, such as graphene, is a young and rapidly growing field. Recently, research into the effects of combining materials both vertically and laterally has been initiated with efforts to custom-build structures with novel properties. The aim of the project is to fabricate heterojunctions from single- and few-layer materials. These are expected to have a broad range of applications, such as the promise of a step change in the capability of thermoelectric devices, or devices capable of sub-photo detection. Importantly, the elements within these 2D materials are generally common, providing a potential alternative to the use of rare elements in modern semiconductor industry. It is also expected that the unusual physics observed within these structures, such as the valley-Hall effect, will provide a pathway to previously inaccessible technologies, creating devices with greater computing power than are currently possible with modern semiconductor technology.

____________________________________________ The role of defect in high performance SiC electronic

Hind Alsnani, Alton Horsfall and Jonathan Goss Silicon carbide (SiC) being an attractive material for electronic device applications due to its superlative properties including, wide band gap, high electron mobility, and its high thermal conductivity. However, this material has a wide range of defects and impurities, which have a detrimental effect on device performance. In this study density functional theory (DFT) as implemented in AIMPRO will used to study the behavior and evolution of common defects in SiC. The simulation will be compared to characteristics from deep level transient spectroscopy (DLTS) in order to identify the evaluation of these defects during high temperature process steps such as implantation annealing and oxidation. The combination of these two methods (DFT&

DLTS) can serve to determine the behavior of the deep levels denoted as Z1/2, EH6/7 centers that are the most common defects in as grown SiC and ascertain their suitability of realize quantum computation qubits.

____________________________________________ Influence of dielectric formation on the operation of 4H-SiC MOSFETs

Muhammad Idzdihar Idris, A.B. Horsfall and N.G. Wright SiC MOSFETs have been suffering with low carrier mobility that hinders the uptake of silicon carbide technology in integrated circuits. The high value of interface state density, Dit at the SiC/SiO2 interface is believed to be the main reason for this problem in the subthreshold region. Reducing the density of interface states at the interface between SiC/SiO2 has become a key challenge in the development of high performance SiC MOS technology. An understanding of the origin of defects at the SiC/SiO2 interface is required to predict the practicable evolution of methods to passivate or eradicate the defects. In this work, the electrical characterization and performance of n and p-type 4H-SiC CMOS structures with different dielectric formation conditions has been performed. From C-V measurements, parameters such as interface state density (Dit), flatband voltage (VFB), threshold voltage (VTH) and effective charge (NEFF) have been acquired to assess the effectiveness of the process.

____________________________________________ Towards large scale accurate Kohn-Sham DFT for the cost of tight-binding

Tiago Marinheiro Using a comparison package developed to assess the error estimates of a DFT code [1], we present results obtained for a specific basis generation procedure in AIMPRO [2,3,4] a Gaussian orbital DFT code. As a further test of accuracy we compare total energies to converged plane wave results. The implementation of the filtration method [2, 3, 4] in AIMPRO is described and preliminary results are presented. A summary is presented which explains how we aim to implement filtration and the basis generation to obtain ‘plane wave accuracy at the cost of tight-binding’.

[1] K. Lejaeghere, et all, Critical Rev. S. S. M. S. 39, 1 (2014)

[2] M. J. Rayson and P. R. Briddon, Phys. Rev. B 80, 205104 (2009).

[3] M. J. Rayson, Comput. Phys. Commun. 181, 1051 (2010).

[4] P. R. Briddon and M. J. Rayson, Phys. Status Solidi B 248, 1309 (2011).

____________________________________________ Defects and interfaces in compound thin film solar cell devices

Fatimah Bahrani, Jonathan Goss and Patrick Briddon Quaternary semiconductors of the I2-II-IV-VI4 family including copper zinc tin sulfide (CZTS) have features which make them well placed to replace silicon, binary and ternary semiconductors in photovoltaic cells (pn-junctions). They are non-toxic, have a high absorption coefficient, have direct band gaps, are low-cost and are made up from earth-abundant elements. In the kesterite crystal structure, the intrinsic lattice defects have a significant role in determining the structural, electronic and electrical properties for the absorber layer in a PV module. Electronic, electrical, and structural properties of material, and defects will be studied using computational methods, primarily being first-principles density-functional theory (DFT). Phase space stability of CZTS relative to secondary phases have been studied. In addition, it is found that intrinsic defects including vacancies and anti-sites are predicted to have a high equilibrium concentration and dope the material electrically. The calculations support the growth conditions in the literature.

____________________________________________ Silicon Carbide MOSFET

Faiz Arith, Jesus Urresti, Amit Tiwari, Konstantin Vasilevskiy, Nick Wright and Anthony O'Neill

The study investigates SiC MOSFET channel mobility following the introduction of an ultrathin SiO2 layer between an Al2O3 gate dielectric and 4H-SiC. A previous paper has reported that by growing an ultrathin SiO2 layer at low temperature underneath Al2O3, the channel mobility increases significantly. This ultrathin (SiO2) is believed to be a good interface layer between SiC and Al2O3 as the combination of Al2O3 and ultrathin SiO2 produces an adequate barrier height by the conduction band offset to render a low leakage current. By increasing the oxide thickness and/or temperature condition, the field effect mobility decreases sharply. It is believed that thermally grown SiO2 generates Ci that can eventually bind to each other and form immobile clusters like (Ci)2 giving rise to a reduction of the carrier mobility. However until now, researchers have not reported a conclusive correlation between those factors believed to be the source of channel mobility reduction.

____________________________________________ Investigation and Manufacture of a Bio-inspired Submersible Through the Use of Soft

Robotic Actuators

Andrew Reid Electro active polymers as robotic actuators, and especially ionic polymer metal composites (IPMCs), have received a great deal of interest within the scientific community due to: their small size; light weight nature; as well as displaying large deformations under relatively small voltages (~1-10V). Underwater exploration holds great promise, for both scientific research and mineral exploitation. Conventional mechanical actuators are greatly effected by pressure, requiring bulky ‘casing’ to operate at depth. This increases the power required for operation as well as the propulsion of the housing craft, reducing mission time. Effect of pressure on the operation of IPMCs is expected to be minimal, negating the need for protective casing. This project aims to produce a bio-inspired submersible modelled on common cephalopods. This project will explore the fabrication of an appropriate IPMC as well as the design of a propulsion system and manipulator suitable for the task.

____________________________________________ Calculating Baligas Figure of Merit in Ge, Si, GaAs and 4H-SiC for Determination of the

Ideal Semiconductor to be used for a Given Temperature Range

Robotic Actuators

Luke Bradley Baligas Figure Of Merit (BFOM) is a metric used to describe the performance of a semiconductor for power electronic applications based on its permittivity, carrier mobility and critical electrical field. In order to determine which semiconductor is most suitable at a given temperature, we first look into the temperature dependence of the carrier mobility in Ge, Si, GaAs, and 4H-SiC via scattering from ionized impurities and optical phonons. The polarisation of dipoles within a material is then shown to be virtually temperature independent with ~2.5% change in Si from 10K to 370K. Finally we approximate the temperature dependency of the critical electric field based on the materials energy gap, saturation velocity, effective mass of carriers and carrier mobility. We have created a model to describe the temperature dependence of BFOM and allow calculations to be made to determine the best semiconductor of choice for a given temperature, from which we have found Ge to be the most suitable material for devices functioning at 20K. .