• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1998.06a
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• pp.59-66
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• 1998

교통정보와 DGPS(Differential GPS) 보정신호의 전송은 ITS(Intelligent Transport System)의 핵심 응용분야인 차량항법시스템(CNS : Car Navigation System)의 동적경로안내(Dynamic Routine Guidance System) 시스템의 핵심적인 요구사항이다. 이 정보들은 서비스 특성상 넓은 지역을 수신지역으로 하고 24시간 연속적으로 전송이 되어야 한다. 즉 주행주인 차량에서 자신의 위치 정확히 파악하기 위한 DGPS 보정신호 및 사고, 교통통제나 체증 등의 교통사항을 항상 수신할 수 있도록 항시 전송이 되어야 한다. FM 방송을 활용하여 이러한 요구사항을 충족시키는 전송채널로 활용될 수 있음을 확인하기 위해 FM 방송과 DARC 방식의 부반송파 시뮬레이터가 제작되었으며 이 시스템의 특성이 연구되었다. 또한 정보데이터를 현용 FM 방송설비를 이용하여 전송하기 위한 방송시스템을 제작하고 서울 및 경기도 지역을 수신지역으로 한 방송수신상태의 측정이 수행되었다. 이 결과들은 FM 부반송이 ITS를 위한 전송채널로서 활용될 수 있다는 것을 보여준다.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.96-96
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• 2000

Today, Internet is an everyone's tool for information searching and communication. Furthermore, with the wireless Internet, we can get connected while moving. The Internet, especially wireless Internet could be an excellent data Link for DGPS because of its interactive two-way communication capability and well-constructed network infra. The user with his own mobile communication device doesn't necessarily get equipped with the other specific data link for DGPS This paper will show that how the Internet based DGPS system could be constructed on the computer network in real time, Its performance is demonstrated by the field experiments. Comparing to the DGPS system with the conventional data Links, Like beacon and FM DARC, the Internet based DGPS could provide us a convenient and cost effect DGPS system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.6
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• pp.22-32
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• 2010

Increasingly advanced Information Technology (IT) has changed the operator so as to create more diversified and advanced traffic information demand. To deal with the changing demand in private sector, a concept of on-demand traffic information has been rapidly introduced. However VMS, a product of the first generation of ITS, which was designed to provide the unspecified individuals during driving the car with the basic level of traffic information by the public failed to actively change itself in such a changing pattern. This study was intended to describe the VMS system (tentatively, FM-VMS) which was further developed to accommodate the needs favoring the sophisticated PDA with the public role of providing the unspecified individuals with the equal information. FM-VMS introduced in this study is the device designed to transmit the voice and message to the drivers through the radio information device mounted on a car. A core technology is, unlike FM-DARC and RDS, the Water Making technology which directly inserts the digital signal into FM frequency in use. It's been currently used for broadcasting and security purpose. A detection rate as a result of testing FM-VMS system using Water Making technology was 90% or more in voice and message within 20m from test VMS. When a public-developed VMS information could be transmitted using FM frequency to the relatively vulnerable users (vulnerable to traffic information) in voice on a real-time basis to provide the regional traffic information, and furthermore, VMS message could be received through radio liquid using FM frequency only, it would obviously bring about the innovation in ITS as well as pave the way for creating the new added value down the road.

• Journal of Life Science
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• v.31 no.9
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• pp.856-861
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• 2021

CD82/KAI1, identified as a metastasis suppressor, was initially known only as a molecular facilitator, but its various functions have recently been revealed. CD82 plays an important role in the stem-progenitor cell, angiogenesis, and muscle. We would like to introduce the recently reported functions and roles of CD82 in this review. CD82 is a member of the tetraspanin family, which consists of four transmembrane domains. The interaction between CD82 and cell adhesion molecules suppresses the metastasis of cancer. CD82 regulates the cell cycle of stem-progenitor cells in the stem cell niche. In the bone marrow, CD82 is expressed on long-term repopulating hematopoietic stem cells (LT-HSCs), which show multipotent differentiation potential. The interaction between CD82 and Duffy antigen receptor for chemokines (DARC) induces quiescence in LT-HSCs. CD82 also regulates Rac1 activity, resulting in the homing and engraftment of HSCs into the bone marrow niche. Besides, CD82 maintains the differentiation potential of muscle stem cells and prevents angiogenesis by inhibiting the expression of cytokines, such as IL-6 and VEGF and adhesion molecules in endothelial cells. CD82 is a key membrane protein that distinguishes the hierarchy of stem-progenitor cells, and is also important for amplification and verification of cellular resources. Further studies on the function of CD82 in various organs and cells are expected to advance cell biology and cell therapy.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.61-64
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• 2004

현재 GPS를 이용한 위성측위시스템은 기존의 DGPS에 의한 정밀도 향상 차원을 넘어 상시관측소를 활용한 기준국의 활용 증대 및 다양한 동시 사용자의 욕구를 충족시키기 위해 여러 가지 연구들이 진행되고 있다 현재 국내 연구동향으로 VRS-RTK (Virtual Reference Station Real Time Kinematic)에 대한 기초 연구가 진행 중에 있으며 해양수산부의 전파를 이용한 비콘 방식과 표준과학연구원 천문대에서는 MBC와 연계한 FM-DARC(Data Radio Channel)방식 등이 활용 방안으로 준비중에 있으며, 여러 기관과 대학 연구 기관에서 기초 연구가 진행 중에 있다. 따라서 이미 독일, 싱가폴, 일본 등에서 활용하고 있는 VRS의 연구를 보다 심화하여 현재 각기 다른 기관에서 보유하고 있는 70여개의 GPS 상시관측소의 효율적인 활용과 대 국민 서비스를 제공할 수 있는 시스템이 절실히 필요한 시기이다. 따라서 본 논문에서는 이런 가상관측의 결과를 산출할 수 있는 통계학적 모델링을 통한 가상관측 보정값을 산출할 수 있는 보정값을 제시할 수 있는 알고리즘 개발에 그 목적이 있다. 향후 알고리즘 개발이 완료되면 통계학적 모델링을 통해 단일 기준점에 의한 GPS 측량에서 불가능한 위치 결정 네트웍의 가상 관측을 가능하게 할 것이며, 신뢰성 있는 미지정수 해를 만들 수 있을 것이다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.3
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• pp.3-13
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• 2002

There are cases that revoke the certification because of disclosure of private key, deprivation of qualification and the expiration of a term of validity on PKI. So, a user has to confirm the public key whether valid or invalid in the certification. There are many methods such as CRL, Delta-CRL, OCSP for the cert-validation of certification. But these methods have many problems, which cause overload traffic on network and the CRL server because of realtime processing for cert-validation of certification. In this paper we proposed cert-validation of certification improvement method based on FM Subcarrier Broadcasting, which solved problems that are data integrity by different time between transmission and receiving for CRL, and overload traffic on network and the CRL server the realtime management.