QR Documentation

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LIST OF FIGURES

1 .Outlook of QR code

2. Features of QR code

3. Devices that support QR code

4. Encoding and decoding of data in QR code

5. QR code generator

6. QR code reader

7. QR code parts

8. Other 2D and QR codes

LIST OF TABLES

1. QR code data capacity

2. Indicators for the type of information present in QR code

3. Version for each type of information

4. Alphanumeric character codes


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ABSTRACT

QR codes, developed by a Japanese company in 1994 (after the invention of smart

phones which was invented in the year 1992), have been around for over fifteen

years. With the advent of smart and Web capable mobile devices, we witness a

steady growth of interesting commercial applications using QR codes.The "QR"

is derived from "Quick Response", as the creator intended the code to allow its

contents to be decoded at high speed. QR Codes are common in Japan, where they

are currently the most popular type of two dimensional codes. Moreover, most

current Japanese mobile phones can read this code with their camera.

As the movement of using QR codes in education is still in its

infancy, this document serves to be comprehensive in understanding to fully

delineate

(a) the user characteristics of QR codes,

(b) the processes of making and reading QR codes,

(c) the survey of commercial applications using QR codes,

(d) the literature review of educational applications using QR codes, and

(e) offer suggestions and implementations of QR

codes in school education

(OUT LOOK OF QRCODE)


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INTRODUCTION

QR Code is a form of 2D bar codes. A sample is shown in Figure 1. It was

developed by Denso-Wave, a Japanese automatic data capture equipment

company (Denso, 2009), in 1994. QR stands for Quick Response. It is

readable by moderately equipped mobile phones with cameras and QR scanners.

Information such as URL, SMS, contact information and plain text can be

embedded into the two dimensional matrix. With smart phones, we can visit the

Website linked by the URL quickly, we can send the SMS message directly or we

can save the contact information onto the address book easily. This format of 2D

bar codes is so popular in Japan and emerges gradually around the world because(a) the patent right owned by Denso Wave is not exercised (Denso, 2010a), (b) its

specification is disclosed to the public by the company so as the specifications,

ISO/IEC 18004:2000&2006 (International Organization for Standardization) and

JIS X 0510 (Japanese Industrial Standards), can be formed (ISO, 2010; JISC,

2010), and (c) it has a large data A QR code is capable of holding 7,089numeric

characters, 4,296 alphanumeric characters, 2,953 binary bytes, 1,817 Kanji

characters or a mixture of them. The data capacity is much higher than other 2D

codes such as PDF417, DataMatrix and Maxi Code (Denso, 2010b). It stores

information in both vertical and horizontal directions. A QR code can be read

from any direction in 360 through position detection patterns located at the three

corners as shown in Figure 1. A QR code can be read even it is somewhat

distorted by either being tilted or on a curved surface by alignment patterns and

timing patterns. The error correction capability against dirt and damage can be up

to 30%. A linking functionality is possible for a QR code to be represented by up

to 16 QR codes at maximum so that a small printing space is possible. The size of

a QR code can vary from 21x21 cells to 177x177 cells by 4 cell-increments in

both horizontal and vertical direction. Data can be easily encrypted in a QR code

to provide a confidentiality of information embedded in the code. It can also

handle various languages. For examples, there are a number of standards adoptedby Asian countries like GB/T capacity in a small printout size and high speed scan

utilities via mobile devices are readily available.


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FEATURES

1.HIGH CAPACITY ENCODING OF DATA:

While conventional bar codes are capable of storing a maximum of approximately

20 digits, QR Code is capable of handling several dozen to several hundred times

more information.QR Code is capable of handling all types of data, such as

numeric and alphabetic characters, Kanji, Kana, Hiragana, symbols, binary, and

control codes. Up to 7,089 characters can be encoded in one symbol

2 .Small Printout Size:

Since QR Code carries information both horizontally and vertically, QR Code is

capable of encoding the same amount of data in approximately one-tenth the space

of a traditional bar code.

(For a smaller printout size, Micro QR Code is available.

QR Code Data capacity

Numeric only Max. 7,089 characters

Alphanumeric Max. 4,296 characters

Binary (8 bits) Max. 2,953 bytes


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3.Dirt and Damage Resistant:

QR Code has error correction capability.Data can be restored even if the symbol is partially dirty or damaged. A

maximum 30% of code words can be restored

4.Readable from any direction in 360:

QR Code is capable of 360 degree (omni-directional), high speed reading. QR

Code accomplishes this task through position detection patterns located at the

three corners of the symbol. These position detection patterns guarantee stable

high-speed reading, circumventing the negative effects of background interference


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SUPPORT

Nokia, Sony Ericsson, Fujitsu Siemens, HTC, i-mate, LG,

Motorola, Palm, Samsung Almost all mobiles Supported


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ENCODING AND DECODING OF DATA IN QRCODE

The format information records two things: the error correction level and the mask

pattern used for the symbol. Masking is used to break up patterns in the data area

that might confuse a scanner, such as large blank areas or misleading features that

look like the locator marks. The mask patterns are defined on a 66 grid that is

repeated as necessary to cover the whole symbol. Modules corresponding to the

dark areas of the mask are inverted. The format information is protected from

errors with aBCH code, and two complete copies are included in each QR

symbol.

The message data is placed from right to left in a zigzag pattern, as shown below.

In larger symbols, this is complicated by the presence of the alignment patterns

and the use of multiple interleaved error-correction blocks.
http://en.wikipedia.org/wiki/BCH_codehttp://en.wikipedia.org/wiki/BCH_codehttp://en.wikipedia.org/wiki/BCH_codehttp://en.wikipedia.org/wiki/File:QR_Character_Placement.svghttp://en.wikipedia.org/wiki/File:QR_Format_Information.svghttp://en.wikipedia.org/wiki/File:QR_Character_Placement.svghttp://en.wikipedia.org/wiki/File:QR_Format_Information.svghttp://en.wikipedia.org/wiki/BCH_code


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Meaning of format information Message placement within a QR code Larger symbol illustrating

interleaved blocks

Four-bit indicators are used to select the encoding mode and convey other

information. Encoding modes can be mixed as needed within a QR symbol .

Indicator Meaning

0001 Numeric encoding (10 bits per 3 digits)

0010 Alphanumeric encoding (11 bits per 2 characters)

0100 Byte encoding (8 bits per character)

1000 Kanji encoding (13 bits per character)

0011 Structured append (used to split a message across multiple QR symbols)

0111 Extended Channel Interpretation (select alternate character set or encoding)

0101 FNC1 in first position (seeCode 128for more information)

1001 FNC1 in second position
http://en.wikipedia.org/wiki/Code_128http://en.wikipedia.org/wiki/Code_128http://en.wikipedia.org/wiki/Code_128http://en.wikipedia.org/wiki/File:QR_Ver3_Codeword_Ordering.svghttp://en.wikipedia.org/wiki/Code_128


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0000 End of message

After every indicator that selects an encoding mode is a length field that tells howmany characters are encoded in that mode. The number of bits in the length field

depends on the encoding and the symbol version, as shown below.

Encoding Ver 19 1026 2740

Numeric 10 12 14

Alphanumeric 9 11 13

Byte 8 16 16

Kanji 8 10 12

Alphanumeric encoding mode stores a message more compactly than the byte

mode can, but cannot store lower-case letters and has only a limited selection of

punctuation marks. Two characters are coded in an 11-bit value by this formula:

V = 45 C1 + C2

Alphanumeric character codes are as follows.

Code Character Code Character Code Character Code Character Code Character

0 0 9 9 18 I 27 R 36 space

1 1 10 A 19 J 28 S 37 $

2 2 11 B 20 K 29 T 38 %


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3 3 12 C 21 L 30 U 39 *

4 4 13 D 22 M 31 V 40 +

5 5 14 E 23 N 32 W 41 -

6 6 15 F 24 O 33 X 42 .

7 7 16 G 25 P 34 Y 43 /

8 8 17 H 26 Q 35 Z 44 :

Decoding of data


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Levels and masks

Protocols


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GENERATION OF QRCODE

To prepare a document embedded with QR codes, the simplest way to do is to

generate the specific codes using some of the tools available from the Internet.

These images can then be embedded into the document at the appropriate places.

If the mobile device does not build in any QR code reader, the user needs to

download the right decoder from the Internet and installs it on to the device. The

following steps illustrate the processes.

Step 1: To encode the required text/SMS/URL/Contact into a QR code, we can

make use of some Websites that can generate the code for us. These include:

1.Kaywa: http://qrcode.kaywa.com/

2.ZXing Project: http://zxing.appspot.com/generator/

3.NFC Games: http://nfggames.com/system/qrcodegen.php

4.Delivr: http://delivr.com/qr-codegenerator

An example with kaywa.com

Step 2: The Website will generate the QR code for you as shown above


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HOW TO READ QRCODE

Step 1: We can save the generated image file and embed it into wherever we want

in the document.

Step 2: We need to load the mobile device with the right decoder. You can find

many application Websites supplied the decoders for different mobile devices.

These include:

1. i-nigma: http://www.i-nigma.com/Downloadi-nigmaReader.html

2. Quickmark: http://www.quickmark.com.tw/En/basic/download.asp

Step 3: We need to install the application into the device

Step 4: For the document with the embedded image, the user can just slide the

decoder over the area and the text will automatically be displayed as shown

below. If the text is an URL, you can just click the link and the reader will take

you to the Website. If the text is a contact record, the reader can save the record to

the address book of the phone with just one click.

An example with i-nigma.com


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QRCODE RULES

Rule 1: Content is King! Make your content valuable!

Rule 2: Mobilize the landing page!

Rule 3: Keep the URL short!

Qrcode data capacity:

Numeric only Max. 7,089 characters

Alphanumeric Max. 4,296 characters

Binary (8 bits) Max. 2,953 bytes

Kanji/Kana Max. 1,817 characters


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Version: This gives the version of the QR code

Format information: Once after encoding the data if the data has to be changed

in the QR code it can be changed

Data and error correction keys: QR code has the capacity of retaining 30%of the lost data if the code is scratched or damaged. This error correction is doneby data and error correction keys.

Position: This consists of position detection patterns located at upper left, upper

right and lower left regions .Each position detection pattern may be viewed as

three superimposed concentric squares and is constructed of dark 7x7 modules,

light 5x5 modules and dark 3x3 modules.

Alignment pattern: Each alignment pattern may be viewed as three

superimposed concentric squares and is constructed of dark 5x5 modules ,light

3x3 modules and a single central dark module .The number of alignment patterns

depend on the symbol version and they shall be placed in all model2 symbols of

version2 or larger in position.


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Timing pattern: The horizontal and vertical timing patterns respectively

consists of a one module wide row or column of alternating dark and light

modules ,commencing and ending with a dark module .The horizontal timing

pattern runs across row 6 of the symbol between the separators for the upper

position detection patterns; the vertical timing pattern similarly runs down column6 of the symbol between the separators for the left-hand position detection

patterns. They enable the symbol density and versions to be determined and

provide datum positions for determining module coordinates.

HARDWARE REQUIREMENTS:

1. Any cell phone with a camera and the ability to install software that can

interpret the code.

2. What the device can do with the resulting data will vary depending on

the devices other features. (i.e. Internet connection)

SOFTWARE REQUIREMENTS:

1.Barcode Scanner (Android)

2.Quickmark (iPhone)

3.BeeTagg QR Code Reader (Windows Phone and Blackberry)

4.UpCode (Blackberry)

ENCRYPTION:

Although encrypted QR Codes are not very common, there are a few

implementations. An Android app,for example, manages encryption and

decryption of QR codes using DES algorithm (56 bits).Japanese immigration use

encrypted QR Codes when placing visas in passports.


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ERROR CORRECTION:

Codewords are8 bitslong and use theReedSolomon error correctionalgorithm

with four error correction levels. The higher the error correction level, the less

storage capacity. The following table lists the approximate error correction

capability at each of the four levels:

Level L (Low) 7% of codewords can be restored.

Level M (Medium) 15% of codewords can be restored.

Level Q (Quartile)[28]25% of codewords can be restored.

Level H (High) 30% of codewords can be restored.

Due to the design of ReedSolomon codes and the use of 8-bit codewords, an

individual code block cannot be more than 255 codewords in length. Since the

larger QR symbols contain much more data than that, it is necessary to break the

message up into multiple blocks. The QR specification does not use the largest

possible block size, though; instead, it defines the block sizes so that no more than

30 error-correction symbols appear in each block. This means that at most 15

errors per block can be corrected, which limits the complexity of certain steps in

the decoding algorithm. The code blocks are then interleaved together, making it

less likely that localized damage to a QR symbol will overwhelm the capacity of

any single block.

Thanks to error correction, it is possible to create artistic QR Codes that still scan

correctly, but contain intentional errors to make them more readable or attractive

to the human eye, as well as to incorporate colors, logos and other features into

the QR Code block
http://en.wikipedia.org/wiki/Octet_(computing)http://en.wikipedia.org/wiki/Octet_(computing)http://en.wikipedia.org/wiki/Octet_(computing)http://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correctionhttp://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correctionhttp://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correctionhttp://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correctionhttp://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correctionhttp://en.wikipedia.org/wiki/QR_code#cite_note-27http://en.wikipedia.org/wiki/QR_code#cite_note-27http://en.wikipedia.org/wiki/QR_code#cite_note-27http://en.wikipedia.org/wiki/QR_code#cite_note-27http://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correctionhttp://en.wikipedia.org/wiki/Octet_(computing)


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COMPARISION OF QRCODE WITH BARCODE

1. Barcodes represented by bars are designed across only one dimension.They are spread across horizontally as well as vertically, and thus theyhave a square appearance in contrast to the single line rectangular looking

bars that barcodes can easily be identified with2. Since the information is stored horizontally in barcode the information

encoded in it is very less when compared to QR code because QR code canstore information both horizontally and vertically

3. The vertical and horizontal layouts of QR codes allow QR codes to containmore information than a barcode can possibly contain. In fact QR codescan hold up to thousands of alphanumeric

4.

Primarily barcodes are used as a means to track product information whereas QR code is versatile i.e it can store any kind of information in anylanguage.

5. Barcode can contain only up to 20 numeric characters .QR code can storevery large amount of information when compared to barcode

6. Since the information is stored only horizontally in barcode the amount ofdata it can store is 1/10th of the information stored by QR code since in QRcode the information is stored both horizontally and vertically.

7. Generally there will be set of numbers below the bar code to retain theinformation present in the barcode if the code is damaged. But in QR codethere is no such necessity since QR code has error correction capacity,30% of the lost information can be retained even if the code is damaged orscratched.

8. Barcode needs a scanner ,QR code needs small devices like mobiles whichcontains QR code scanner in it. Bardode doesnt need internet connection

like QR code.


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APPLICATIONS

QR code cab be any

Text

Website URL

Telephone Number

SMS Message

Contact Details (VCARD)

Google Map

Facebook Profile

Brands can use QR codes in all kinds of new ways to reach consumers.

QR codes can be used on posters and billboards, providing anyone with a cell

phone immediate access to everything from information on consumer prize

campaigns to addresses and maps for retail outlets QR codes are also handy for

various branding purposes. They can be used to direct mobile phone users to

special websites to download brand ads, ringtones, character logos, viral videos,

branded flash games and more.

Similarly, movie studios make it easy to view coming attractions by printing QR

codes on posters that are hung all over the world. Scan the codeyou're watching

previews of films right on your phone

1.Fast food brands can print QR codes on sandwich wrappers. One quick scan and

you're instantaneously provided with nutritional and/or ingredient information.

2.Retailers can print them on receipts.

3.Event producers employ them to provide exhibit information

4.Doctor's offices and beauty salons use them to let people make appointments

over their mobile phones.

5.Companies can print them on business cards so clients and suppliers can suck

contact info right into their cell phones and PDAs.

6.TV shows can use QR codes to appear on the corner of the screen to provide

product information


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Other 2D codes:

1.Micro QR Code 35 Characters

2.High Capacity Color Barcode3500 characters per square inch

QR code types:

Why QR codes have to stay?

1. Sharing content over the web has become ridiculously popular over the last 5-7

years.

2. Sharing content over the MOBILE web is still pretty new, but has explosive

potential! You are already seeing it with adoption of text messaging (texting)

and Twitter (tweets), which are both mobile born forms of communication.

3. Everything MUST be easy to share on-the-go (i.e., galleries and product

pages). Make it easy for users to post content on Facebook and Twitter in seconds.

4. Make sure that the content is accessible on the web also. Mobile to desktop

sharing is still prominent.


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License:

The use of QR Codes is free of any license. The QR Code is clearly defined and

published as an ISO standard.Denso Wave owns the patent rights on QR Codes,

but has chosen not to exercise them.In the USA, the granted QR Code patent

is US 5726435 and in Japan JP 293833. The European Patent Office grantedpatent "EPO 0672994" to Denso Wave, which was then validated into French,

British and German patents, all of which are still in force as of November

2011.The word QR Code itself is a registered trademark of Denso Wave

Incorporated.In UK, the trademark is registered as E921775, the word QR

Code, with a filing date of 03/09/1998.The UK version of the trademark is based

on the Kabushiki Kaisha Denso (DENSO CORPORATION) trademark, filed as

Trademark 000921775, the word QR Code, on 03/09/1998 and registered on

6/12/1999 with the European Union OHIM (Office for Harmonization in the

Internal Market)

Variants:

Micro QR Code is a smaller version of the QR Code standard for applications

with less ability to handle large scans. There are different forms of Micro QR

Codes as well. The highest of these can hold 35 numeric characters.

Standard QR Code is the QR code standard for applications that possess the

ability to handle large scans. A standard QR Code can contain up to 7,089

characters, though not all QR readers can accept that much data.

Custom or artistic QR codes are standard QR codes that have been modifiedfor aesthetic purposes or to make it easier for people to recognize a brand. Many

companies use different design techniques to help their code stand out among the

crowd. These techniques include: adding color, shapes and various techniques

such as round or pointed edges.

Risks:

Malicious QR Codes combined with a permissive reader can put a computer's

contents and user's privacy at risk. This practice is known as "attagging",

a portmanteau of "attack tagging."They are easily created and may be affixed over

legitimate QR Codes On a smartphone, the reader's many permissions may allow

use of the camera, full internet access, read/write contact data, GPS, read browser

history, read/write local storage, and global system changesRisks include linking

to dangerous websites with browser exploits, enabling the microphone/

camera/GPS and then streaming those feeds to a remote server, analysis of

sensitive data (passwords, files, contacts, transactions), and sending email

/SMS/IM messages or DDOS packets as part of a botnet corrupting privacy

settings, stealing identity and even containing malicious logic themselves such

as JavaScript or a virus. These actions may occur in the background while the user

only sees the reader opening a seemingly harmless webpage.


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ADVANTAGES AND DISADVANTAGES

Advantages:

1. There is no need to write vital details down. A simple scan captures thedesired information.

2. QR Codes can be used to store addresses and URLs that can appear inmagazines, on signs, buses, business cards or just about any product that

users might need information about.3. QR code provides personal information security

Disadvantages:

1. Users must be equipped with a camera phone and the correct readersoftware that can scan the image of the QR Code.

2. Currently only Smartphones are technically equipped to do this. Manyusers that have mobile phones that have cameras are unable to get QRreading software for their phones.

3. The other disadvantage is user must have knowledge about the code.


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CONCLUSION

This document, provided a holistic view of using QR codes in industry and in

education. This demonstrated broad areas to apply QR codes in school education.

Overall, the students participated in the experiment found that the activities were

interesting. Naturally, the students at this age group were very curious about these

new approaches to their otherwise routine exercises. But with this age group, we

have additional concerns. First, we must categorically prepare enough mobile

devices for the activities. We definitely cannot expect students at the junior levels

to carry the right mobile devices to schools. For exercises conducted individually

like Mail Trail, the problem is not acute. However, the cost would be prohibitive

for a large group of participants. Second, despite it is quite easy to operate a

mobile device equipped with a QR code reader, we noticed some students highly

tilted the devices when they snapped the codes. Students at this age group need to

be trained properly. Third, if the mobile devices are equipped with Wi-Fi access

and the activities do have the wireless coverage, the cost for communication

would be minimal. Otherwise, we may need to rely on 2G/3G communication

provided by mobile carriers. This option can be very expensive.In general, webelieve that QR codes have great potential in education. Some possibilities are

demonstrated in this paper and there are many creative ideas waiting for us toexplore. Also, this document can be served as the first step for the readers to

investigate this exciting topic of mobile learning.


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REFERENCES

[1] Chaisatien, P., & Akahori, K. (2007). Demonstration of an Application on 3G

Mobile Phone and Two Dimension Barcode in Classroom Communication

Support System. In C. Montgomerie & J. Seale (Eds.), Proceedings of World

Conference on Educational Multimedia, Hypermedia and Telecommunications

2007 (pp 3330-3336). Chesapeake, VA:AACE (EDMEDIA 2007)

[2] Denso (2010a). QR Code Standardization. Retrieved June 21, 2010, from

http://www.denso-wave.com/qrcode/qrstandard-e.html

[3]Denso (2010b). About 2D Code. Retrieved June 21, 2010, from

http://www.densowave.com/qrcode/aboutqr-e.html

[4]Denso (2009). Denso Wave Incorporated. Retrieved June 21, 2010, from

http://www.denso-wave.com/en/index.html

[5]Elena (2009). Educational Qrcodes. Retrieved June 21, 2010, from

http://www.qrcode.es /?p=350&language=en

[6]ISO (2010). ISO/IEC 18004:2006. Retrieved June 21, 2010, from

http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=43655

[7]ITSC (2008). Section 3: QR Code. Synthesis Journal. Information Technology

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http://www.itsc.org.sg /pdf/synthesis08/Three_QR_Code.pdf

[8]JISC (2010). JIS X 0510:2004. Retrieved May 15, 2010, from

http://www.jisc.go.jp/app /pager?id=12766 (written in Japanese)

[9]JISC (2005). Innovative Practice with e-Learning: a good practice guide to

embedding mobile and wireless technologies into everyday practice Bristol:

[10]Joint Information Services Committee.Kukulska-Hulme, A., & Traxler, J.

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[11] London: Routledge.Liu, T., Tan, T., & Chu, Y. (2007). 2D Barcode and

Augmented Reality Supported English Learning System. Proceeding of the 6th

IEEE/ACIS International Conference on Computer and Information Science (pp

5-10). IEEE Computer Society.


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[12]Naismith, L., Lonsdale, P., Vavoula, G., & Sharples, M. (2005). Literature

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[13]NWT (2010). The National Math Trail. Retrieved September 20, 2010, from

http://www.nationalmathtrail.org/

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Kondo, K. (2007). Outdoor Education Support System with Location Awareness

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[16]Sharples, M. (Ed.) (2007). Big Issues in Mobile Learning. LSRI, University of

NottinghamSo, S. (2008). A Study on the Acceptance of Mobile Phones for

Teaching and Learning with a group of Pre-service teachers in Hong Kong.

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[17]Susono, H., & Shimomura, T. (2006). Using Mobile Phones and QR Codes

for Formative Class Assessment, In A. Mndez-Vilas, A. Solano Martn, J.A.Mesa Gonzlez and J. Mesa Gonzlez (Eds), Current Developments in

Technology-Assisted Education (Vol. 2) (pp 1006-1010). Badajoz, Spain:

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