• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.5
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• pp.776-796
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• 2010

Integrated RFID-WSNs (wireless sensor networks) have recently been researched to provide object identities, sensing information, mobile service, and network functionalities. In integrated RFID-WSNs, the reader collision is one of the critical problems. Above all, due to the absence of universally applicable anti-collision protocols and the channel capture phenomenon, the medium access control protocols in integrated RFID-WSNs suffer from reader collision and starvation problems. In this paper, we propose an efficient MAC protocol, called EMP, to avoid the above problems in integrated RFID-WSNs. EMP is a CSMA-based MAC protocol which is compatible with sensor networks operating on integrated nodes which consist of an RFID reader and a senor node. EMP resolves not only the reader collision problem, but also the starvation problem using a power control mechanism. To verify the performance of EMP, we compared it with other anti-reader collision MAC protocols using simulations. As a result, the performance of EMP showed improvements in throughput, system efficiency, and energy consumption compared to the single data channel protocols (CSMA/CA, Pulse, and DiCa) in dense deployment environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10B
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• pp.885-893
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• 2008

In RFID system, reader collision happened when multiple readers try to read the tags at the same time. Because reader collision reduces tag recognition performance, it is required for RFID system to have reader anti-collision algorithm. In this paper, we propose reader anti-collision algorithm based on hierarchical structure, where a master reader controls the slave readers to avoid the reader collisions. It is verified through simulations that the proposed algorithm enhances the performance in terms of leader collision probability and tag reading time.

• 한국IT서비스학회:학술대회논문집
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• 2009.05a
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• pp.415-427
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• 2009

Diffusion of information technology such as internet has brought a great influence on modern society and industrial development. Currently wide-spread RFID/USN technology has become a central momentum of this rapid changes for the establishment of ubiquitous society in the future. Historically agricultural products has drawn research interest due to its importance of human life. A standard monitoring system throughout of life cycle of the agricultural products should be developed and careful monitoring process should be introduced. In this paper, by way of case study, current lifetime tracing systems are evaluated and critical drawbacks and issues are also developed. In addition, some implications and guidelines to improve the tracing performance of the products are also suggested.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.63-64
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• 2017

In this paper, we studied a design method for a coplanar waveguide-fed compact quasi-Yagi antenna for a dual band of the UHF RFID (915 MHz) and GPS (1.575 GHz). The proposed antenna is composed of three elements of a dipole, a reflector, and a director. To reduce its size, the ends of both the dipole and reflector are bent, the director is placed near to the dipole, and a balun is incorporated in the antenna. From some simulations, the proposed antenna using an FR4 substrate with 0.8 mm thickness was designed for the operations in the UHF RFID and GPS systems, and the antenna characteristics such as reflection coefficient, gain, and radiation patterns were examined.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.11
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• pp.2026-2031
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• 2006

Various kinds of studies for building up U-Korea are now underway. Especially, many results of educational application field such as U-Learning and U-Campus applying a USN technique have been founding. There are not, however, enough researches for the student management related to elementary, middle and high school. Therefore, this paper will suggest effective application system of student management which is one of the application systems for a user - centered environment using RFID and NEIS system in Ubiquitous. This system is enable to make it efficiently managed and transmitted students' data about their location and the details of their counsel(career, health and so on).

• Aerospace Engineering and Technology
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• v.7 no.1
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• pp.236-244
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• 2008

The evolution and application of RFID technologies have been at the forefront of allowing aviation industries to improve the quality of aircraft maintenance and air cargo handling. However, safety problems in airplane operation are arising from the hazards of frequencies transmitted due to RFID systems. Though the intensities of frequencies back-scattered from the tags are very weak, some malfunctions are anticipated due to induction coupling on aircraft wiring. Therefore, safety assessment such as electromagnetic compatability should be accomplished upon aircraft critical and essential equipments before installations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.634-639
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• 2007

Despite continuous changes these days, exhibit management methods have not changed that much. To solve th problem, some systems like bar code, color code, IrDA, etc. are being used, but still many problems remain. For the problem-solving, "Exhibt Management System with RFID" is designed and its prototype is developed, which can reduce resources and efforts to manage exhibits through that an operator confirms exhibit information and inputs any damage on the exhibit on the site by using RFID system. The system purposes to improve efficiency of exhibit management by allowing an operator to check all information of exhibitions in real time using a portable reader that recognizes tags of 900MHz band manually attached to each exhibit.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.325-332
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• 2012

Due to its communication vulnerability resulting in a range of problems, e.g. eavesdropping, information exposure, traffic analysis and spoofing, RFID system becomes the target of attackers. Accordingly, many investigators have proposed various protocols to the extent of theorem proving or verification as the implementation is challenging. This paper thus proposes a safe RFID security protocol using public keys, session keys, hashes, XORs, and random numbers. Timestamps and hashes are applied to the most vulnerable section between readers and tags to detect attacks in attack signals with time difference. Also, to prevent tag information from being exposed in the last session, hash operation is adopted before communication. Finally, in this paper, we designed a RFID security protocol using public and session keys applicable to real systems and verified the security of the proposed protocol with a differentiated formal verification technique.

• The Journal of the Korea Contents Association
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• v.9 no.5
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• pp.197-205
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• 2009

With the introduction of the computer, convenience at work may have increased but flexibility decreased along with a tendency for humans to become secondary to computers with regards to work schedules. As it exists, from entering the department of radiology to completion of imaging requires a great deal of time and difficulties in understanding the imaging process adds to patient dissatisfaction. Since clinics use RFID bars to track patient locations at comprehensive medical testing centers, departments of radiology may apply RFID and Worklist at the core of the OCS system in order to increase work efficiency and improve work flow. As a result of developing an RFID and Worklist centered OCS program, there was a vast improvement in patient satisfaction and work flow. Theses results are the basis of an RFID system that in the future may be connected to PACS and other systems with an intergrated Worklist. There is a need to realize a plan the can offer ubiquity to hospital work.

• The KIPS Transactions:PartD
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• v.18D no.2
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• pp.111-122
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• 2011

These days RFID application has been developed rapidly. It has been applied to many business areas such as logistics and supply chains. The Electronic Product Code (EPC) Network Architecture, an open global standard, is proposed by EPCglobal for developing RFID enabled systems. People who want to obtain the product information which are master information and event information have to apply with EPC Network Architecture. However, EPCIS which has master information and event information has to be accessed base on each EPC. Therefore, there is lots of duplicate accessing to EPCIS because RFID application has to access the same EPCIS over again which makes all performance down in EPC Network. This paper proposes how to reduce access times to EPCIS using EPC grouping based on EPCIS address. We build EPC Network environment to experiment about performance of RFID application system and we prove the improvement of EPC Network. Our result shows the reducing the EPCIS communication time by maximum 99 percentages.