• Journal of IKEEE
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• v.8 no.2 s.15
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• pp.195-206
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• 2004

In an RFID system, it is desirable to have both the reader and the transponder tuned to the same resonant frequency for efficient data transmission between them. Any difference in frequency will decrease the transponder coil voltage or the internal power supply voltage and will increase the possibility of zero modulation in the reader coil, which results in the reduction of the reading distance. In this paper, the phenomena caused by the frequency mismatch are theoretically analyzed and mathematically modelled. Several schemes to compensate for the frequency mismatch are also mentioned. The derived equations and analyzed theory on the data transmission between the reader and the transponder will be helpful to the development of RFID systems for many applications.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.6C
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• pp.626-633
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• 2009

ISO/IEC/WD 24753 defines new modem specifications for a long-range RFID communications and application protocol for a sensor tag system. According to the standard, the frequency offset of the tag is 4%. In general wireless communications systems, it is known that a coherent receiver is superior to a non-coherent receiver. However, if the frequency offset is large, it is difficult to restore the original data accurately with a coherent receiver, and the performance of a coherent receiver is easily degraded. In this paper, a non-coherent receiver structure is adopted to solve the frequency offset problem of long-range RFID communications. We designed a frequency estimation block to find an optimal frequency from the received signal with 4% frequency offset and proposed a start frame delimiter (SFD) detection algorithm to determine the start position of the payload. The frequency estimation block finds the optimal frequency from the received signal using 9-correlators. And the SFD detection block searches the received signal to find the start position of the payload with dual correlator. We implemented a long-range RFID reader with the proposed methods and evaluated its performance in a wired/wireless test network. The implemented long-range RFID reader showed more superior performance than the commercial RFID reader in terms of recognition range.

• Journal of Navigation and Port Research
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• v.32 no.5
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• pp.349-353
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• 2008

In this paper, the EM wave absorber was designed and fabricated for preventing Reader Interference of RFID communication system in UHF band We fabricated several samples in different composition ratios of Amorphous and CPE(Chlorinated Polyethylene). Absorption abilities were simulated in accordance with different thicknesses of the prepared absorbers and changed complex relative permittivity and permeability due to composition ratio. The mixing ratio of Amorphous and CPE was searched as 80 : 20 wt.% by experiments and simulation. Then the EM wave absorber was fabricated and tested using the simulated data. As a result, the developed EM wave absorber has a thickness of 4 mm and absorption ability was over 20 dB in frequency range of $860\;MHz{\sim}960\;MHz$. Therefore, it was confirmed that the developed absorber can be used for suppressing RFID reader interference in UHF band.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.404-412
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• 2011

More recently, variety RFID (Radio Frequency Identification) readers are produced by RFID equipment manufactures. Although a transmission standard instituted by EPCglobal is proposed for data transmission between the RFID readers and tags, other RFID reader protocols and the communication connection methods are be in use in other RFID companies. To replace or add the RFID readers of an RFID system, the developers should make changes to the core of the application and/or middleware. In this paper, we propose an RFID reader framework which can manage RFID readers without having to make changes the code of the application in environment with the growing number of heterogeneous RFID readers.This framework that sits on the layer between the RFID readers and the applications provides transparency to the RFID readers. Additionally, it can be used for monitoring the state and the property of all connected RFID, and for recording the RFID tag event logs and system logs. By using this framework, heterogeneous readers can be replaced and added without writing additional code in the applications. Consequently the readers can be easily managed and controlled by the RFID system administrator.

• Journal of Korean Library and Information Science Society
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• v.41 no.4
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• pp.73-98
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• 2010

This study discussed the roles of librarians in readers' advisory services and the education for readers' advisory services in LIS programs. For this, literatures were reviewed and readers' advisory courses provided by LIS programs of North America were investigated. And then the characteristics and contents of readers' advisory courses were analyzed. Based on the analysis, I suggested the education for readers' advisory services in LIS programs of Korea.

• Proceedings of the KAIS Fall Conference
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• 2008.11a
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• pp.316-319
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• 2008

본 논문에서는 유아의 장난감에 RFID 시스템을 도입하여 유아가 흥미있어하는 장난감에 Tag를 삽입하고 Display 장치 부근에 RFID-Reader를 설치하여 장남감이 Reader 근처에 위치하게 되었을 때 장난감에 해당되는 학습정보를 Display 장치를 통하여 보여준다. 본 논문의 결과 유아가 장난감을 가지고 노는 동안에 영상, 음성 등의 콘텐츠를 Display 장치를 이용하여 보여주고 들려 줌으로써 자연스럽게 장난감의 정보를 학습할 수 있도록 하였다. RFID의 인식률과 인식거리를 감안하여 13.56MHz의 수동형 태그를 사용하였으며, 최대 인식거리는 20Cm에서 인식할 수 있도록 하였다. 실험은 RFID의 인식률과 콘텐츠의 자동인식 및 실행에 중점을 두었으며, RFID의 인식은 하나의 태그 인식에서는 99%이상의 성공을 하였고 두개이상의 태그에 대해서는 첫 번째 태그만을 인식할 수 있게 설계하여 콘텐츠를 실행하도록 하였다.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.3
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• pp.143-153
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• 2011

Digital leader caught seat by modern's everyday life tool now by popularization of smart device such as Smart phone and Tablet PC. Therefore, desire of readers about electronic book practical use is increasing based on convenience and economic performance of electronic book. 1971, Michael S. Hart established Project Gutenberg to produced first electronic book because inputs American Independence Declaration Statement by computer and produce more electronic books. After that, an electronic book technology repeats several times development and American electronic book take is increasing rapidly. Sales volume of electronic books is dramatically increasing in Korea since digital device such as Smart phone and Tablet PC became popular. This research attempts to analyze factors influencing on shifting from paper book to electronic book. Results of this research proposed grounds for building business strategy. Finding is the factor of social influence is only significant to acceptability intention. It means user of e-Book enhance their acceptability intention along social phenomena.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.243-248
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• 2002

The International Space Station (ISS) offers research opportunities for researchers in the field of remote sensing to conduct world-class activities in Low Earth Orbit. ISS provides the facilities to place and operate research experiments in a variety of fields, providing investigators opportunities to perform research and Earth observation. This paper is intended to give the reader an introduction to the ISS utilization and the capabilities for remote sensing research that are being implemented through the development of research facilities. We hope that reader will consider what kind of payloads could be developed to take advantage of facilities, and will consider proposing remote sensing research on the ISS.

• Journal of the Society of Disaster Information
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• v.13 no.4
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• pp.476-482
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• 2017

For the bridges managed by the municipalities, there is a need for a maintenance management system for the municipal governments for the scientific and systematic maintenance standard and the scientificization of the budget acquisition and execution through the quantified data base. The purpose of this study is to develop a system for efficient management of small bridgies maintained by the municipality and use ICT convergence technology such as BIM / GIS technology. The details of the system development include the development of the small bridgies maintenance program for mobile devices, the development of the small bridgies maintenance database, the development of the small bridgies integration maintenance management, and the reliability of the program system developed by checking the construction and operation contents of the small bridgies test-bed. The developed program system is linked to the development of smart name plate and reader module of non - power system.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.109-117
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• 2006

This paper deals with the middleware development for real time data processing using ubiquitous RFID(Radio Frequency Identification). This middleware system supports the real time data gathering, filtering, and collaborative operations within SCM. We expect to decrease the data processing cost and to upgrade the status of RTE(Real Time Enterprise) and competitive power of company.