• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.132-135
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• 2002

In radio communication technology, SDR(Software Defined Radio) technology is emerging as a trendy technology for future. SDR is expected to change existing radio systems including central hardware. SDR is equipment that wireless parameters (frequency, modulation, additional service, power level, receive sensitivity, etc.) are controlled by software. In the world, equipments using the new technology are spreading. Not only equipments being imported but also local manufacturers are making this equipment, developing software and offering upgraded service. In the future, as SDR spreads and users choose the service, diverse equipments will be developed through competition and individual development. This diversity of equipment and services will introduce problems in compatibility and interoperation issues. So the government will have to make technical standard for SDR service and will have to make theses standards available to users and manufacturers alike. Therefore I am investigating the elements that can be used to establish these standards.

• Journal of Astronomy and Space Sciences
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• v.25 no.2
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• pp.227-238
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• 2008

GNSS (Global Navigation Satellite System) Ground Station monitors navigation satellite signal, analyzes navigation result, and uploads correction information to satellite. GNSS Ground Station is considered as a main object for constructing GNSS infra-structure and applied in various fields. ETRI (Electronics and Telecommunications Research Institute) is developing Monitoring and Control subsystem, which is subsystem of GNSS Ground Station. Monitoring and Control subsystem acquires GPS and Galileo satellite signal and provides signal monitoring data to GNSS control center. In this paper, the configurations of GNSS Ground Station and Monitoring and Control subsystem are introduced and the preliminary design of Monitoring and Control subsystem is performed. Monitoring and Control subsystem consists of data acquisition module, data formatting and archiving module, data error correction module, navigation solution determination module, independent quality monitoring module, and system operation and maintenance module. The design process uses UML (Unified Modeling Language) method which is a standard for developing software and consists of use-case modeling, domain design, software structure design, and user interface structure design. The preliminary design of Monitoring and Control subsystem enhances operation capability of GNSS Ground Station and is used as basic material for detail design of Monitoring and Control subsystem.

• Journal of KIISE:Information Networking
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• v.36 no.1
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• pp.34-42
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• 2009

In this paper, we propose a practical hybrid transport error control scheme to provide SVC video streaming service over error-prone IP networks. Many error control mechanisms for various video coding standards have been proposed in the literature. However, there is little research result which can be practically applicable to the multilayered coding structure of SVC(the scalable extension of H.264/AVC). We present a new hybrid transport error control scheme that efficiently combines layered Forward Error Correction(FEC) and Automatic Repeat Request(ARQ) for better packet-loss resilience. In the proposed hybrid error control, we adopt ACK-based ARQ instead of NACK-based ARQ to maximize throughput which is the amount of effective data packets delivered over a physical link per time unit. In order to prove the effectiveness of the proposed hybrid error control scheme, we adopt NIST-Net network emulator which is a general-purpose tool for emulating performance dynamics in IP networks. It is shown by simulations over the NIST-Net that the proposed hybrid error control scheme shows improved packet-loss resilience even with much less number of overhead packets compared to various conventional error control schemes.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.145-147
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• 2003

홈 제어 네트워크는 전력선으로 대표되는 물리적 네트워크를 기반으로 저속의 신뢰도 있는 통신을 한다. 현재 홈 제어 네트워크의 표준으로 거론되고 있는 것들은 CEBUS, EIB, LonWorks 등이 있다. 본 논문에서는 ETRI에서 작년에 개발한 론웍스(LonWorks) 시스템을 구성 관리하는 서버 소프트웨어인 LonWare(version 2.0)의 다중 바인딩을 지원하기 위한 연결(Connections) 구조를 제안한다. Echelon사에서 제안하는 LonWorks 시스템의 구성관리 도구로서의 LonMaker는 자체적으로 개발한 LNS (LonWorks Network Service)라고 하는 비 표준화된 구성 관리 기술을 통해서 네트워크를 관리하도록 지원하며, 상기한 LNS를 인프라로 활용하는 도구로서, LNS는 빌딩 혹은 가정 내에 LonWorks 네트워크로 연결되어 있는 디바이스들에 대한 정보를 DB화하여 구축된 자료를 기반 으로 디바이스들간에 연동이 가능하도록 지원한다. 그러나 고가이며, 바인딩 과정 시 론웍스 네트워크 상에 필요 이상의 패킷을 발생시켜 전력선 채널의 Bandwidth를 감소시키며, 또한 바이딩 과정을 마치는데 걸리는 시간을 증가시킨다. 이에 본 논문에서는 다중 바이딩을 지원하는 홈 네트워크 구성 관리 서버 소프트웨어의 연결 구조를 통해서 LonWare v2.0의 유니캐스트(unicast) 바이딩시 발생 했던 모든 문제를 제거하고, 바인딩에 필요한 패킷을 최적화 하여 바인딩에 걸리는 시간을 단축시키며, 성능의 주요한 요소인 디바이스의 리소스를 최소화하는 방법으로 접근하여 바인딩 시 처리능력의 한계를 가지고 있는 뉴런칩 기반의 론웍스 디바이스의 시스템 사양에 영향을 주지 않도록 제안하였다. 제안된 리눅스 기반의 홈 네트워크 구성 관리 소프트웨어의 다중 바인딩 기능을 통해 론웍스 네트워크상의 다양한 디바이스들간의 네트워크 다양화와 분산화 기능을 얻을 수 있었고, 기존의 고가의 해외 솔루션인 Echelon사의 LonMaker 소프트웨어를 사용하지 않고도 국내의 순수 솔루션인 리눅스 기반의 LonWare 3.0 다중 바인딩 기능을 통해 저 비용으로 홈 네트워크 구성 관리 서버 시스템 개발에 대한 비용을 줄일 수 있다.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.491-496
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• 2009

In this paper, we propose USN Protocol of Room Control with high efficiency and new routing techniques. I establish a network of cluster hierarchy structure under bases standard for IEEE 802.15.4 and another networks to manage each room use a control packet transmitted and The proposed protocol does not perform BroadCast over a network and transmits a packet to same layer to the destination and then passes the packet after doing searches. If a destination to be transmitted cannot be looked up, the protocol transmits AODV routing packet so that not only traffic load of a wireless network is decreased, but also efficient routing path can be obtained.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.344-344
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• 2020

기후변화 가속화와 국민의 높아진 서비스 요구 수준에 따라 농업용수의 관리방식을 현장인력의 경험적 물관리 방식에서 계측정보 기반의 과락적 물관리 방식으로 전환의 필요성이 대두되어, 2001년부터 농업기반시설 내 무인계측, 원격제어 기능이 탑재된 물관리자동화 시스템을 보급하는 농업용수관리자동화사업을 시행하였다. 농업용수관리자동화사업은 사업시행 초기 연구 결과, 농업기반시설 무인계측 및 원격제어 시스템 보급으로 인력에 의한 관행적 물관리 대비 수리시설의 관리 효율성이 크게 향상되어 유지관리 인력의 절감 및 용수수급의 적정성이 개선될 것으로 분석되었다. 하지만 영농환경의 변화에 따라, 당초 분석결과와 달리 자동화사업 추진과 한국농어촌공사의 유지관리 인력 규모 간 뚜렷한 상관성이 보이지 않는다는 정책기관의 지적이 발생하고 있다. 현재 4차산업기술이 산업 전 분야에 걸쳐 일어나고 있으며 농업분야에도 ICT, LOT, 빅데이터 기술이 도입되어 새로운 가치를 창출하고 있다. 농업용수관리 분야에 있어서는 데이터를 활요한 수요자 중심의 지능형 물관리 사업이 추진되고 있으며, 일정규모 이상 저수지 및 양수장 농업용수 공급량 측정 계측기의 설치가 추진중에 있다. 그러나 현재까지 이러한 설치된 계측장치들의 활용방안에 대해서는 뚜렷한 결과가 도축된 바 없으며, 현재 많은 예산과 인력이 투입되어 설치·운영되고 있는 계측장치들의 활용 방안에 대해서 연구가 필요한 실정이다. 2018년 2,228개 농업기반시설물에 자동화시스템을 설치 완료 하였으나, 각종 장비의 비표준화, 효과대비 고비용, 잦은 통신두절 등의 기술적 문제로 인해 현업부서의 수자원관리 업무에서 자동화시스템의 활용성이 저조한 것으로 관측됐다. 본연구에서는 국내 수자원 계측제어 기술 동향 및 운영환경 조사 결과를 기초로, 기술적 측면의 농업용수관리자동화사업의 개선사항과 4차 산업기술의 농업용수관리자동화사업의 적용방안을 제시 하여 농업용수관리자동화사업 중장기 계획 개정등 향후 정챡수립시 참고 자료로의 활용과 농업용수 효율적 활용과 관리를 위한 TM/TC 미래추진 방안을 제시로 정확하고 신뢰도 높은 농업용수 관리 체계를 구축 하고자 한다.

• Journal of KIISE:Information Networking
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• v.34 no.5
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• pp.405-422
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• 2007

Recently, according to the network environment, there are many researches for home network. Nowadays, in home network, the method that access control policy is managed for each home device by using ACL is popular, and EAM (Extranet access management) is applied as a solution. In addition, the research about secure OS is ongoing based on open operating system and the research of user authentication mechanisms for home network using home server is also in progress. However, these researches have some problems as follows; First, the transmission scope of expected access technology in home network is wide, so unauthenticated outside terminal can access the home network. Second, user is inconvenient because user need to set the necessary information for each device. Third, user privacy and convenience are not considered. OSGi provides a service platform for heterogeneous technologies in home network environment. Here, user access control is one of the core parts which should have no problems such as above items, but there are no concrete researches yet. Thus in this paper, we propose an access control policy management framework and access control operation based on RBAC for user access control in home network environment in which OSGi service platform is operated. First, we list the consideration which is not clearly mentioned in OSGi standard, and then we solve these above problems through new framework. In addition, we propose the effective and economical operation method which reduces the policy change frequency for user access control by using RBAC concept though limited resource of home gateway. Besides, in this paper, these proposed policies are defined separately as user-role assignment policy and permission-role assignment policy, and user decide their own policies. In conclusion, we provide the scheme to enhance the user convenience and to solve the privacy problem.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.180-186
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• 2020

ICT convergence using smart livestock is that in the first-generation dairy smart farm model, each device made by several manufacturers uses its own communication method, limiting the mutual operation of each device. This study uses a model based on open control technology to secure interoperability of existing ICT devices and to manage data efficiently. The open integrated control derived from this process is the software interface structure of Open API. It is an observer that serves as real-time data collection according to the communication method of ICT devices and sensors located at each end. It consists of a broker that connects and transmits to the upper integrated management server. As a result of the performance analysis through verification of two first-generation dairy smart farm model sites, the average daily milk production increased compared to the previous year (farm A 5.13%, farm B 1.33%, p<0.05). Cow days open (DO) was reduced by 17.5% on farm A and 13.3% for farm B(p<0.05). Cows require an adaptation period after the introduction of the ICT device, but if continuous effects are observed, the effect of production can be expected to increase gradually.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.678-681
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• 2007

In this study, an implementation of a system for measuring more accurate blood pressure by non-invasive methods of oscillometric was performed. The system were composed of pressure control, signal measurement, blood pressure signal processing units and wireless sensor network parts. For verify the validity of the system, tests of characteristics evaluations for pressure measurement unit, extraction of characteristic ratios for blood pressure estimation, blood pressure tracking by oscillometric method were performed. A group of five adult male was selected for the clinical test of the implemented system. The results of the oscillometric method in comparison with auscultatory method are that the maximum ratios of PAD of average, systolic and diastolic arterial pressure are 1.38%, 1.63% and 2.97% with SEP of 5.00, 3.72 and 4.34.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.5C
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• pp.411-421
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• 2002

In this paper, we present a new survivor path memory management method and a dedicated hardware architecture for the design of high-speed Viterbi decoders in modern digital communication systems. In the proposed method, a novel use of k-starting node number deciding circuits enables to acheive the immediate traceback of the merged survivor path from which we can decode output bits, and results in smaller survivor path memory size and processing delay time than the previously known methods. Also, in the proposed method, the survivor path memory can be constructed with ease using a simple standard dual-ported memory since one read-pointer and one write-pointer, that are updated at the same rate, are required for managing the survivor path: the previously known algorithms require either complex k-ported memory structure or k-times faster read capability than write. With a moderate hardware cost for immediate traceback capability the proposed method is superior to the previously known methods for high-speed Viterbi decoding.