• 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.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.3
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• pp.199-206
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• 2013

This paper proposes a modified tag collection algorithm that improves the drawback of the identified slot scan-based tag collection algorithm presented in a previous paper to improve the tag collection performance in active RFID systems. The previous identified slot scan-based tag collection algorithm is optimized in situations where all the tags store the fixed size of data, so it could not result in a good performance improvement with tags having the variable size of data. The improved tag collection algorithm proposed in this paper first collects the slot size information required for the data transmission from each tag via the identified slot scan phase, and then performs the tag collection phase using the information, which resolves the problem of the previous identified slot scan-based tag collection algorithm. The simulation results for performance evaluation showed that the proposed tag collection algorithm resulted in the almost same tag collection performance as the previous algorithm when all the tags have the same size of data and led a large improvement of the tag collection performance in ISO/IEC 18000-7 unlike the previous algorithm when each tag has a random size of data.

• Information Systems Review
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• v.13 no.3
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• pp.15-26
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• 2011

RFID has substituted for a Bar Code to conduct real time data collection and data process in various fields including logistics, electronic, medical treatment, car, textile, steel industry at the business level. Although implementation and use of RFID has been facilitated constantly, the majority of businesses hesitate to implement RFID system. Hence in this study, we conducted a performance evaluation through quantitative/qualitative analysis on case studies in various industries. This study results could be utilized as basic data for RFID system diffusion, and it will primarily contribute to spread of RFID system implementation.

• 전자공학회논문지 IE
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• v.48 no.4
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• pp.7-12
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• 2011

This paper described a metal mount RFID tag that works reliably on metallic surface. The proposed method is to use commercial RFID tags, Styrofoam103.7 material is attached on back side of RFID tag. Styrofoam103.7 material which has 2.5 mm thickness and 1.03 relative permittivity, was attached on back side of RFID tag. In order to verify the performance of proposed method, we evaluated the experiment on the supply chain system of electric transformers using RFID. The experimental results on supply chain of electric transformers show that the proposed tags can communicate with readers from a distance of 2 m. The results of recognition rates are comparable to commercial metallic mountable tags.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1367-1371
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• 2013

The RFID market seems to grow mostly in the logistics and distribution areas. The areas and small sized work places requires multi-steps based system. In the environment, the performance of RFID READER is the most important factor. If RFID READER fails to operate frequency well, it will be difficult to apply RFID technology to work places and manage multi-readers used in a narrow place. This work reveals that making possible multiple readers environment and reporting the state of the entire upgrade are of significant in terms of the system's functions. This thesis studied RFID reader platform with self-diagnosis function.

• Journal of Internet Computing and Services
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• v.12 no.6
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• pp.139-147
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• 2011

We proposed the secure and efficient passive RFID protocol which is based on one-way hash based low-cost authentication protocol (OHLCAP). The paper introduces OHLCAP and the vulnerabilities of OHLCAP and suggests security solutions by analyzing them. Afterwards, The paper presents the proposed protocol and demonstrates computational performance and security of the protocol. This protocol not only has the resistances against eavesdropping attack, impersonation attack, desynchronization attack, and replay attack but also provides untraceability and forward secrecy.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12B
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• pp.1686-1697
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• 2011

This paper aims to build up a RFID-automated cargo movement system in an air-cargo warehouse. In our research, we do the spectrum measurements compliant with the RFID frequency bands to observe the interferences from legacy systems in the air-cargo warehouse. To overcome the dense-reader mode (DRM) problem, we apply three novel approaches, which are the periodic transmit of a reader, the Visible RFID reader & tag, and the sensor-based RFID system. Moreover, for the tag collision issue, we implement the Adaptive Adjustable Framed Q(AAFQ) algorithm, and the demonstration on RFID tag anti-collision algorithms show that the AAFQ algorithm has highly desirable tag anti-collision performance compared to any other commercially available solutions.

• International Commerce and Information Review
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• v.6 no.2
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• pp.171-191
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• 2004

Recently, RFID(Radio Frequency IDentification) is observed with government and connection enterprises as the central figure. RFID utilizing radio is a technology that enable exchange of information sensing and recognize object. RFID is expected that the practical use limits widens by territory that can form vast market such as logistics management according to RFID's low-cost aggravation as well as usage of life and improvement of performance because present R&D is gone vigorously. Because RFID is possible application everywhere if it is various service industries as well as logistics, industry spot, manufactory and place that flowing of goods is, is used, and is becoming big limelight from society several territories.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10b
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• pp.120-124
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• 2007

RFID(Radio Frequency Identification) 시스템은 다양한 분야에서 혁신을 제공하는 기술로써 관심의 대상이 되고 있으며 여러 분야에서 RFID 기술을 도일하기 위해 연구되고 있다. 특히 많은 사업 분야에서 RFID 기술을 이용하기 위해 연구가 이루어지고 있다. RFID 시스템의 특성상 다양한 도메인에서 이용되기 때문에 여러 가지 장애가 발생하게 된다. 하지만 이렇게 발생한 다양한 장애들을 탐지하고 진단하는 일은 쉽지 않다. 본 논문에서는 다양한 도메인에서 이용되는 RFID 미들웨어 시스템의 특성을 고려하여 RFID 미들웨어 시스템에 적합한 장애 탐지 기법과 장애 진단 기법을 제시한다.