Web-based real-time temperature monitoring of shellfish catchesusing a wireless sensor network
Karl Crowleya, June Frisbya, Seamus Murphyb, Mark Roantreeb, Dermot Diamonda,∗a Adaptive Sensors Group, National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland
b Interoperable Systems Group, Dublin City University, Dublin 9, Ireland
Received 12 August 2004; received in revised form 3 May 2005; accepted 20 May 2005Available online 1 July 2005
liminating the need for repeated manual checks. Practical issues arising from implementation of the system are identified and pf the system during field trials is assessed in comparison with commercially available temperature loggers.2005 Elsevier B.V. All rights reserved.
eywords:Wireless sensor network; Web-based interface; RF communication; Temperature monitoring; Mobile communications; Seafood spoila
. Introduction
In recent times, health scares in the food sector haveemonstrated the need for increased safety and quality.
n 2002, the European Union established the Europeanood Safety Authority (EFSA) charged with restoring andaintaining consumer confidence in food safety[1]. Oneay of achieving this aim is through improved traceabilityf the product; allowing the consumer full access to relevant
nformation [2]. In terms of the fishing industry, place ofrigin is often the only information supplied. However, full
raceability is now being implemented through initiativesuch as the Tracefish project[3], where the full history –rom harvest to home – is detailed. Of fisheries products,hellfish in particular are extremely sensitive and careust be taken during their storage and transport, especiallys regards storage temperature monitoring. To date, thisften involves time-consuming manual checks even though
emperature, one of the most important parameters to affect
fish/shellfish quality, is possibly the easiest to meaand control automatically. Indeed in a previous study,need for an autonomous temperature logging systemthe fishing industry was identified[4]. This need may bsatisfied through the use of wireless sensor networks.
A key benefit of real-time wireless sensors isthey allow appropriate action to be taken directly or eautomatically adjust their mode of operation dependincircumstances (adaptive sensing). The use of wireless snetworks in routine monitoring is becoming increasinwidespread in a wide variety of fields. Vivoni and Camdetailed a wireless network and database system allonumerous field teams equipped with radio freque(RF)-enabled PDAs and laptops to carry out coordinateddetailed water quality monitoring[5]. Yun et al. proposedwireless system for monitoring heavy metals in the enviment based on electrochemical analysis[6]. In a review owireless sensor networks, Akyildiz et al. detailed a varof possible applications including health, military, envirmental and home aspects[7]. However, little work has beeconducted as regards wireless sensor networks in trace
E-mail address:[email protected] (D. Diamond). and food safety applications. Internet-based interfaces are
K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230 223
another recent innovation, allowing for remote control of sys-tems and access to sensory information. Fujita and Maenakadescribed an integrated physical sensor capable of uploadinginformation through Ethernet TCP/IP protocol for remoteviewing over the internet[8], while Toran et al. developed avirtual instrument for monitoring water quality that generatedHTML reports and e-mail alarms for remote users[9].
To date, much effort is focussed upon a number ofphysical and chemical sensors suitable for incorporationin a wireless sensor platform. At present, issues such ascost, reliability and need for continuous calibration meansthat commercially available, low cost physical sensors (i.e.thermistors, photodiodes) are generally favoured over morecomplex chemical sensors or biosensors[10]. However,new approaches to chemical sensing are driving down thecost, but maintaining analytical performance. Particularlypromising are LED devices for colorimetric measurements[11] and lab-on-a-chip systems for environmental moni-toring [12]. The LED devices are relatively inexpensive,making them ideal for scale-up to wide-area sensor net-works. Prior to incorporation of these complex sensors ina network, it is desirable to perform testing of wirelessarchitecture in real applications to determine potentialissues. In this paper, a wireless sensor network for real-timetemperature monitoring of shellfish catches on inshoretrawlers is described. The system is autonomous and canb s forf turei andc sibles ared
2
nd an lessR datas gingsi te ont
• ck.on-mitd thetion
this
• rs.aseSM
henmote
Fig. 1. Schematic diagram detailing the operation of the wireless tempera-ture logging network architecture and web-based interface.
access to real-time temperature information or previouslystored logs of specific catches from particular trawlers.
The archived temperature information is useful in terms oftraceability and can be used by processors, distributors, super-markets and consumers to ensure the correct storage con-ditions have been met for a particular catch. However, thisfunction can be covered through the use of contact-basedloggers (where data is downloaded through physical contactonce the logger is recovered) or time–temperature integrators(TTIs)—small sensors that integrate temperature changesover time, usually by changing colour, i.e. thermochromicdyes[13]. However, the key benefits from the wireless systemlie in the real-time nature of the data availability. In this par-ticular case, whelk are extremely sensitive to environmentalconditions and must be transported live since spoilage occursalmost immediately after death. International regulations asregards ideal storage conditions for shellfish vary widely.Under Irish regulations, live whelk must be transported attemperatures between 2 and 10◦C [14]. Exposure to temper-atures outside this range will rapidly result in death of thewhelk and loss of the catch. The limitation of contact-basedtemperature loggers is that they can only indicate problemsafter the event has occurred. However, real-time data collec-tion over the wireless sensor network allows for correctiveaction to be taken as soon as temperatures stray outside thea o thec ship).
3
3
wereb td.( ndb el iously
e controlled through web-based software, which allowunctional querying of real-time and archived temperanformation. The performance of the system is evaluatedompared with commercially available loggers and posolutions for improved and/or enhanced operationiscussed.
. Description of wireless temperature logging system
In its current form, the logging system is based arouumber of individual nodes that transmit data using wireF to a base station that communicates with a remoteerver by GSM modem. A schematic diagram of the logystem and web-based software is given inFig. 1. When fully
mplemented, the wireless sensor network would operawo levels:
At the local level, i.e. on board a particular trawler/truThe local level network is composed of loggers that mitor temperature in individual whelk boxes and transthe data back to the base station deployed on boartrawler or truck through radio frequency communica(433 MHz, see below). The base station processesdata, including a time stamp and logger ID number.At the macro level, incorporating a group of trawleIn this case, the data collected by the individual bstations is transmitted to a central server over the Gmobile phone network. The received information is tuploaded onto a web-based database, allowing re
cceptable range, thus minimising any costly losses tatch (e.g. through text messages to personnel on board
. Hardware
.1. RF/GSM temperature logging system
The RF temperature loggers and GSM base stationuilt under contract by Whistonbrook Technologies LLuton, UK). Photographs of the interior of a logger aase station are presented inFig. 2 and schematics of th
ogger/base station system have been presented prev
224 K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230
Fig. 2. Photographs of the interiors of: (a) a RF temperature logger and (b)a base station.
[15]. These two elements of the network have very differentrequirements. The loggers are designed to be mass deployable– built with low-cost components and with minimal powerconsumption, while the base station requires enhanced func-tionality and power – though only one unit is required pertrawler or truck. The construction and functionality of thelogger and base station is detailed below.
The major components of the logger are highlighted inFig. 2a. The loggers comprise of a circuit board poweredby two AA batteries and are capable of functioning con-tinuously for several months. The board and batteries arefully sealed within a waterproof plastic casing measuring142 mm× 84 mm× 25 mm. The temperature is monitoredthrough a 5 K 679–434 thermistor (0.1◦C resolution, Far-nell), not visible inFig. 2a as it is embedded in thermallyconductive epoxy in the logger wall. This improves loggerresponse to ambient temperature changes[15]. The transmit-ter assembly consists of a 433 MHz Micro TX RF transmitter(LPRS Ltd.) with a fine tune control and printed aerial. The
reed switch allows switching between two data acquisitionmodes. The default setting allows data to be acquired at 5 minintervals—employed during the field trials. The other settingacquires data at 5 s intervals and is used for diagnostic test-ing. The current mode is indicated by the LED. The loggeris controlled by a low power PIC16LF872 microprocessor(Microchip Technology Inc.) and when not communicatingdata, the logger resides in a sleep mode to conserve power.
FromFig. 2b, it can be seen that the base station is con-siderably more complex than the logger. It is also largerwith dimensions of 188 mm× 188 mm× 130 mm. The datatransmitted by the loggers is collected by the AM-HRX3receiver (LPRS Ltd.) via the externally mounted RF aerial.Once received, the raw 10-bit data string is processed by aPIC16LF870 CPU (Microchip Technology Inc.) into a 20-bit string containing a 4-bit ID tag, 4-bit temperature valueand 12-bit time stamp (provided by an on-board real-timeclock) and stored in the EEPROM memory (32 kB upgrade-able to 128 kB). When a download is requested from theserver (usually every 15 min—set by user), the processed datais generally transferred over the mobile network via the TC35GSM modem (Siemens). In areas of weak coverage, the GSMaerial could be deployed externally of the base station (∼1 mextension lead). Alternately, data could be transmitted viaa serial port in the sealable control panel allowing a directdownload to laptop though this function was only used ford omF adeu unit.I cityi thel reforei ggersd last1
3
wereo storeu udy,t RFlD tem-p twos e sta-t wlera t thee
4
owf ands hich
iagnostic testing and not during field trials. It is clear frig. 2b that a large portion of the base station bulk is mp for by the 12 V lead-acid battery used to power the
n addition to powering the GSM modem, this extra capas required as the base station has to listen for data fromoggers and download requests from the server, and thet cannot enter a sleep mode to conserve power as the loo. Under normal operating conditions, the battery would–2 weeks.
.2. iButton contact loggers
The model DS1921-F51 iButton temperature loggersbtained from Dallas Semiconductor. These devices canp to 2048 data points at 1–255 min intervals. In this st
he time interval was always set to 5 min to match theogger. The resolution is 0.5◦C with an accuracy of±1.0◦C.uring the trials, one iButton was attached to each RFerature logger to allow a direct comparison between theystems. Another iButton was also attached to the basion to monitor ambient air temperature on board the trand delivery truck. The acquired data was downloaded and of the field trial.
. Prototype system
A web-based prototype with an XML database is nully operational. The GSM connection, data transfertorage was managed by a networked Pentium 4 PC, w
K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230 225
acted as a remote data server. The controlling software anddatabase are completely web-based and can be accessed usinga web browser on any Internet capable device (e.g. PC, laptopor PDA) through a password-protected connection. In thesestudies, the field trials were controlled and data acquisitionmonitored using a GPRS enabled XDA II Pocket PC (O2Ireland)[16]. Through the web interface, the software allowsthe following procedures to be performed:
• initiation/cessation of trial;• in-trial verification of data acquisition and querying of pre-
viously recorded data;• control of multiple base stations simultaneously;• access to a user-defined rule mechanism that allows trig-
gers for particular events to be set, e.g. reporting problemssuch as temperatures outside of upper/lower control levels,loss of communication, etc;
• data storage in a database with tabular or graphic outputand query functionality.
The appearance of the web interface automatically adjustsdepending on the type of platform used. Screenshots of theinterface are given inFig. 3(for the XDA II) andFig. 4(for adesktop PC). In trials, the software was initiated and config-ured remotely using the XDA II. After entering a usernameand password, the user is presented with the main menu. Theca
1 aseenu.sing
connection has been set up, the remote access platform(e.g. PDA) can be disconnected as the remote server PCwill manage the data downloads automatically. As partof the download process, data, which is transmitted asa series of numbers, is captured and processed by an“enrichment process” and converted to XML documents[17].
2. Graph: Presents a graph of the last 12 data pointsdownloaded, i.e. allows rapid in-trial verification of data(requires Java).
3. Queries: This provides the query menu allowing forstandard user querying or the more specific (XPath)querying[18]. XPath queries require database specialistsbut provide maximum flexibility in the form of almostunlimited querying. User queries are more general,allowing easy selection of parameters for either graphicalor tabular form. In either form, queries can be madeusing drop-down menus for a number of parameters suchas logger number, date, time and temperature. Extendedquerying is also available via by drop-down menus thatallow text data to be entered in a flexible manner, e.g.name of captain/ship, type of catch, etc. An example oftabular results on the XDA II is given inFig. 3a, while anexample of graphical results on a PC is given inFig. 4.
4. Rules: The software can be configured to flag warningswhen storage conditions stray outside acceptable limits.
ulesrulened
5s. In
n a PD
hoices offered by the main menu (visible on the left inFig. 4)re as follows:
. Connection: Initiates a connection with a particular bstation, which can be selected from a drop down mPrior to initial connection, base stations are set up uthe configuration screen as given inFig. 3b. Once the
Fig. 3. Screenshots of the web-based interface o
The rule menu allows the user to add/edit/delete rgoverning trigger events for these warnings. Ataxonomy and XML-based rule language were desigspecifically for this task.
. Configuration: The configuration screen (Fig. 3b) allowsthe user to add, edit and delete base station setting
A: (a) tabular results screen and (b) configuration screen.
226 K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230
Fig. 4. Screen shot of the web interface graphical results screen on a desktop PC.
addition to the base station dial-up number and auto redialsettings required for the connection, relevant informationabout the ship, captain, type of catch, etc., can be enteredand can be queried through the database.
6. Logout: Disconnects from the system.
5. Field trials
The temperature logging trials were carried out in conjunc-tion with Errigal Iasc, based in Carrick, Co. Donegal and BordIascaigh Mhara (BIM), the Irish Fisheries Board. The trialswere carried out on inshore trawlers, based at Howth Har-bour in Co. Dublin, which fish for whelk in Dublin bay. Theboats generally departed the harbour between 7 and 9 a.m., atwhich point the loggers and base station were activated. Forthe initial trials, prior to implementation of the web-basedsoftware, control of trials and data verification were handledby personnel based on land who communicated informationto the trawler/delivery truck via mobile phone. In later trials,the web-based software and XDA II Pocket PC were used,allowing full control in real-time while on-board the trawleror truck.
During the trial, the base station was set up in a convenientlocation (usually between 3 and 10 m from the boxed whelk)and the RF loggers, with the attached iButtons, were addedt mpera wlerr es ofw log-g lant( ed.
On arrival at the processing plant, the loggers were removedfrom the fish boxes and the base station turned off.
6. Results and discussion
Typical results obtained during a field trial for an iButtonlogger and one of the RF loggers within the wireless sensornetwork are given inFig. 5. In terms of measured tempera-ture, the custom built RF logger displayed a nearly identicalprofile to the commercial iButton unit, demonstrating theaccuracy of the logger data. Examples of data obtainedfrom a full field trial from the time of catch of the whelkuntil delivery are given inFig. 6, during which the ambienttemperature was again monitored by iButtons attached to the
F mper-a
o the boxes as the catch was being harvested. The teture data was recorded throughout the day until the traeturned to port, generally in the late afternoon. The boxhelk were transferred, along with the base station anders, to a delivery truck for transport to the processing p∼250 km) during which the temperature logging continu
-
ig. 5. Comparison of temperature logs obtained using the wireless teture logging system and an iButton temperature logger.
K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230 227
Fig. 6. Temperature logs of whelk harvest from time of catch until deliveryat the processing plant. Acquired in (a) February and (b) July.
base-station.Fig. 6a details the temperature history of a catchin February 2004. During the period at sea, (10:00–16:00 happroximately), the temperature remained below the upperthreshold at approximately 8◦C. At 16:00 h, the trawlerreturned to dock and the whelk catch was transferred directlyto the delivery truck (non-refrigerated). The temperatureremained below 10◦C for the overland journey to the pro-cessing plant (16:00–22:00 h approximately). For this trialit can be seen that full communication of information wasachieved with no breaks in the datasets. The temperature dataalso confirms that proper storage conditions were maintainedduring the entire period, while at sea and during transportto the processing plant, which is to be expected in view ofthe relatively low ambient temperatures that day. InFig. 6b,the temperature history of whelk caught in July 2004 isdetailed. The loggers reported relatively high initial ambienttemperatures (over 20◦C, due to storage in a black canvasbag) prior to addition to the whelk catch at which point arapid temperature drop was observed (between 9:00 and10:00 h approximately). During the period at sea, (roughly10:00–16:00 h), all three loggers reported temperaturesconsistently above the upper threshold of 10◦C. The threeloggers reported slightly different temperatures (approxi-mately 12, 15 and 13◦C for loggers 1–3, respectively), due
Fig. 7. Average temperature values obtained over several months for whelkstored on board the trawler. Values calculated from data collected whileloggers were in whelk boxes.
to differences in the depth at which the sensor was located inthe whelk (logger 2 sensor was nearer the top of the catch andtherefore reported slightly higher temperatures). On transferto the delivery truck (16:10 h), refrigerated in this case, thetemperature is seen to drop steadily to approximately 8◦C.Over a period of several months, the archived temperaturelog data can be processed and analysed to identify seasonaltrends and/or issues within the transfer chain. An exampleof this is given inFig. 7. Average temperatures for whelkstorage on board the trawler are calculated from the tem-perature logs and are plotted against the date of catch. At aquick glance, it is clear that serious breaches of the 10◦Cthreshold regularly occur during the summer months. Thisresult highlights the difficulties of adequate storage on boardsmall, inshore trawlers with no refrigeration system.
From the above it can be seen that data processing canyield even more information. Implementing data process-ing within the web-based database would allow interestedparties to rapidly perform analyses into a wide variety ofvariables. One simple method, already implemented underthe Query option, is the ability to analyse the data for spe-cific occasions when temperatures cross the threshold limits.Other possibilities for data processing include further statisti-cal analysis (e.g. temperature spread about the mean) and theintegration of temperature data, yielding similar informationto time–temperature integrators. Variations in storage temper-a bed,a ctivet , duet
tingh onenti ls tod
• mu-rverin),e was
ture arising from location (e.g. depth) can also be prolthough care must be taken to ensure there is an effe
ransfer of data from loggers located deep within a catcho signal attenuation.
In terms of temperature logging hardware, the field-tesas allowed a comprehensive evaluation of each comp
n the system and the main points arising from the triaate are as follows:
In nearly all cases, the base station successfully comnicated data through the GSM network to the DCU sePC at the specified time interval (either 15 or 30 mdespite passing through areas where network coverag
228 K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230
incomplete. Where a connection could not be made, thebase station paused until a clear signal was re-establishedbefore transmitting the data. A particularly good resultwas the ability of the base station to transmit data frominside the truck container, thus making external aerialsunnecessary.
• Radio frequency communication between the loggers andbase station onboard the trawler proved more problematicthan expected due to reflection of the signal from the metalhull of the trawlers and absorption of the signal by whelkbody tissue. InFig. 6b, a long break in communicationfrom logger 2 is seen prior to 11:57 h. In this case anobstruction had been placed between the logger and basestation. At 11:57 h, the logger and base station wererepositioned (resulting in the break after 12:00 h) andthe signal was eventually recovered. Other breaks intransmission were noted for logger 1 during the truckjourney with only sporadic communication observed.Nevertheless, careful placement of the loggers in whelkboxes on commencement of the trial generally resulted inclear, interruption-free data transmission (Fig. 6a), readilyvalidated by checking the real-time data log throughthe XDA II. Any communication breaks noted in latertrials were generally due to whelk boxes being movedbehind a metallic obstacle or beyond the range of the basestation.
practical obstacles need to be overcome. At present, on-boardpersonnel add the loggers manually to the shellfish boxesonce the catch is made. However, it is anticipated that loggersmay eventually be physically incorporated into the boxes,eliminating this need. In terms of integration with existingtechnology, one possibility may be to flag warnings throughuse of the commonplace mobile phone. A number of recentstudies have utilised the universal Smart Messaging Servicefor control and/or telemetric purposes in home network[22],health[23] and environmental applications[24]. As statedearlier, the web-based software currently has the capabilityto flag warnings to the web browser when proper storageconditions are not being met or gaps in data transmission areoccurring with specific loggers. Therefore, the relevant per-sonnel can be rapidly notified through SMS alerts on theirmobile phone that corrective action is necessary without theneed for continually checking data through PDA or desktopPC.
In terms of future work, we are currently evaluating theimplementation of the strategies discussed above in the nextgeneration of wireless temperature sensors. Another objec-tive is the integration of the wireless temperature loggingproject with smart packaging research; colorimetric sensorspots being developed for the detection of spoilage prod-ucts (e.g. amines) from whelk and other fisheries products[25]. When implemented, this would yield full traceabilityt up top per-a witho to thes
7
turel pliedt erya llingI ed int nths.I beeni athl signa hasp erep o bee initi-a abled
A
yceo his
he issues outlined above for RF communication are clurmountable. The inclusion of improved transmittersven two-way communication in the loggers, will hnsure no data is lost. However, increasing transcower and complexity will result in greatly increased poonsumption, always a major concern where autonomensor networks are concerned[7,19]. This could be avoidey employing multi-hop communication between loggs this would dramatically reduce the necessary transmiistances[7]. Another possibility is the use of transmiss
requencies less susceptible to absorption interferencehelk tissue, as biomedical studies on human tissuehown varying absorption in the UHF range (MHz-raF) [20,21]. Designing the logger so the temperature seas at one end (to be buried deep in the box of whnd the aerial at the other (clear of interference) wlso be a simple way of reducing interference. Inase, staff on-board can be automatically alerted via Sessaging Service (SMS) text messages from the s
f data gaps are detected by error checking routines inoftware.
In further developing the technology, considerationo be given to current needs and practices of the indun addition to quality control and traceability benefits,mportant aspect in promoting real-time temperature logo fishermen and producers is to minimise the impacstablished working practices and integrate the systemxisting technology as far as is possible. With the intentioeveloping completely autonomous operation, a numb
hrough temperature logging of the temperature historyrocessing and packaging, integrated with continued temture logging throughout the distribution chain, coupledn-package sensor spots to monitor freshness throughupermarket and consumer.
. Conclusion
A wireless sensor network for real-time temperaogging of seafood produce has been developed and apo the monitoring of whelk catches from harvest to delivt the processing plant. The sensor network and contro
nternet-based software have been thoroughly checkhe field by means of trials conducted over several mossues relating to breaks in the RF telemetry havedentified and methods of minimising absorption and posses proposed with a view to improving system dend specifications. Generally, GSM communicationerformed very well, especially in circumstances whroblems with poor network coverage were expected tncountered. GSM communication of the data can beted and configured remotely through any Internet capevice and once initiated, it is completely autonomous.
cknowledgements
We would like to thank Errigal Fish Ltd. and John Jof the Marine Institute for cooperation and support. T
K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230 229
work has been funded by Bord Iascaigh Mhara throughthe Quality Certification, Added Value, Traceability andWorking Conditions sub-programme of the Fishery Devel-opment Plan (Code: 04.SM.T1.19). Funding has also beenreceived from Enterprise Ireland through an AdvancedTechnology Research Programme (ATRP) grant (Code:TD/03/124). We would also like to thank Science FoundationIreland for grant aiding the Adaptive Information Cluster(Code: SFI03/IN3/1361).
References
[1] EFSA Webpage,http://www.efsa.eu.int/.[2] T. Børresen, Traceability in the fishery chain to increase consumer
confidence in fish products—application of molecular biology tech-niques, in: Proceedings of TAFT 2003, Reykjavik, Iceland, June11–14, 2003, pp. 180–184.
[3] Tracefish Homepage,http://www.tracefish.org/.[4] K. McAteer, D. Raftery, D. Diamond, Temperature logging of fish
[5] E.R. Vivoni, R. Camilli, Real-time streaming of environmental fielddata, Comput. Geosci. 29 (2003) 457–468.
[6] K.-S. Yun, J. Gil, J. Kim, H.-J. Kim, K. Kim, D. Park, M. su Kim, H.Shin, K. Lee, J. Kwak, E. Yoon, A miniaturized low-power wirelessremote environmental monitoring system based on electrochemicalanalysis, Sens. Actuators B 102 (2004) 27–34.
[21] L.C. Chirwa, P.A. Hammond, S. Roy, D.R.S. Cumming, Electro-magnetic radiation from ingested sources in the human intestinebetween 150 MHz and 1.2 GHz, IEEE Trans. Biomed. Eng. 50 (2003)484–492.
[22] M.-C. Tang, C.-N. Chou, C.-H. Tang, D.C. Pan, W.-K. Shih, Exploit-ing GSM short message service for ubiquitous accessing, J. NetworkComput. Appl. 24 (2001) 249–267.
[23] L. Boquete, I. Bravo, R. Barea, M.A. Garcıa, Telemetry and controlsystem with GSM communications, Microprocessors Microsyst. 27(2003) 1–8.
[24] T. Ozkul, A. Al Homoud, Communication protocol for monitoringa large number of remotely distributed hazardous material detectiondevices, Comput. Standards Interfaces 25 (2003) 553–561.
[25] L. Byrne, K.T. Lau, D. Diamond, Monitoring of headspace totalvolatile basic nitrogen from selected fish species using reflectancespectroscopic measurements of pH sensitive films, Analyst 127(2002) 1338–1341.
Biographies
Karl Crowley received a BSc in applied science (physics and chem-istry, 1998) and a PhD in analytical chemistry (2003) from the DublinInstitute of Technology. In September 2003, he began a postdoctoralresearch position in the National Centre for Sensor Research (NCSR)in Dublin City University. His current research interests include wire-l alitya
J menti thep earch.H oducea ensors
S 96,w ultantw stersb gritys e isa eb-b
M gh,S Inter-o tions,D per-a tionsa as ofd rojectsh cares a ands
D ast( DublinC peerr tor ine s andd choolo entref thea tive
[7] I.F. Akyildiz, W. Su, Y. Sankarasubramaniam, E. Cayirci, Wiresensor networks: a survey, Comput. Networks 38 (2002) 393–
[8] T. Fujita, K. Maenaka, Integrated multi-environmental senssystem for the intelligent data carrier, Sens. Actuators A 97(2002) 527–534.
[9] F. Toran, D. Ramırez, A.E. Navarro, S. Casans, J. Pelegrı, J.M. Espı,Design of a virtual instrument for water quality across the InteSens. Actuators B 76 (2001) 281–285.
10] D. Diamond, Internet scale sensing—analytical science andnext communications revolution, Anal. Chem. 76 (2004) 2286.
11] K.T. Lau, S. Baldwin, R.L. Shepherd, P.H. Dietz, W.S. YerzunisDiamond, Novel fused-LEDs devices as optical sensors for cometric devices, Talanta 63 (2004) 167–173.
12] M. Sequeira, M. Bowden, E. Minogue, D. Diamond, Towaautonomous environmental monitoring systems, Talanta 56 (2355–363.
13] T.F. Mendoza, B.A. Welt, S. Otwell, A.A. Teixeira, H. KristonssM.O. Balaban, Kinetic parameter estimation of time–temperaintegrators intended for use with packaged fresh seafood, J.Sci. 69 (2004) 90–96.
14] Irish Government Website, Shellfish (Handling, StorageTransport) Regulations, 1979, http://www.irishstatutebook.ieZZSI157Y1979.html.
15] K. Crowley, J. Frisby, S. Edwards, S. Murphy, M. RoantreeDiamond, Wireless temperature logging technology for the fisindustry, in: Proceedings of IEEE Sensors, Vienna, Austria, Oc24–27, 2004, pp. 571–574.
16] Full specification for the XDA II pocket PC is availablehttp://web.o2.ie/business/phonesanddevices/xda/specifications.jsp.
17] C. Goldfarb, P. Prescod, The XML Handbook, Prentice Hall, NJersey, 1998.
18] XML Path Language (XPath) 2.0, W3C,http://www.w3.org/TRxpath20, 2004.
ess sensing and colorimetric/spectrometric analysis for food qupplications.
une Frisby received a BSc in applied chemistry and quality managen 2001 from the Waterford Institute of Technology. She is currently inrocess of completing a PhD at the National Centre for Sensor Reser research interests include wireless sensing for pork and fish prs part of quality programmes and the development of colorimetric spots for smart packaging applications.
eamus Murphy graduated from Queens University Belfast, in 19ith BSc in mathematics and computing. He became an IT consithin the financial sector. In October 2003, he commenced a May research at Dublin City University. His research field is an inteervice for distributed XML databases within a P2P architecture. Hlso working closely with the NCSR in developing software for a wased real-time temperature monitoring system.
ark Roantree received his PhD from Napier University, Edinburcotland (computing, 2001). He is currently group manager of theperable Systems Group (ISG) in the School of Computer Applicaublin City University. His research objectives are to provide interobility between information systems, and to facilitate complex transaccross a distributed architecture. This research covers the areatabases, programming languages and data distribution. Recent pave included the provision an interoperable framework for healthystems and e-commerce transactions involving non-textual datecurity.
ermot Diamond received his PhD from Queen’s University BelfChemical Sensors, 1987), and was Vice President for Research atity University, Ireland (2002–2004). He has published over 100
eviewed papers in international science journals, is a named invenight patents, and is co-author and editor of two books on sensorata processing. He joined DCU in 1987 as a member of the Sf Chemical Sciences, and is a founder member of the National C
or Sensor Research (www.ncsr.ie). In 2003, he helped to negotiateward ofD 5.6 million from Science Foundation Ireland to the ‘Adap
230 K. Crowley et al. / Sensors and Actuators A 122 (2005) 222–230
Information Cluster’ (AIC), a joint initiative linking the NCSR, theCentre for Digital Video Processing (DCU) and the Smart Media Institute(University College Dublin). He is currently Director of the AIC. Hisresearch interests are wide ranging, from molecular recognition,host–guest chemistry, ligand design and synthesis, electrochemicaland optical chemical sensors and biosensors, lab-on-a-chip, sensor
applications in environmental, clinical, food quality and processmonitoring, development of fully autonomous sensing devices, wirelesssensors and sensor networking. He is particularly interested in developingthe potential of analytical devices and sensors as information providersfor wireless networked systems, i.e. building a continuum between thedigital and molecular worlds.
