• 방송공학회논문지
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• 제12권3호
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• pp.203-213
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• 2007

지상파 DMB(Digital Multimedia Broadcasting)에서 비디오 서비스에 이어, 본격적인 데이터 서비스가 시작되고 있는데, 교통여행정보 서비스는 그 중에서도 핵심적인 데이터 서비스로 간주되고 있다. 본 논문은 교통여행정보 서비스를 제공하기 위한 방송시스템의 설계와 구현방안을 제안하기 위한 것이며, 전체 시스템은 저작 시스템, DB 시스템, 송출 시스템 및 모니터링 시스템으로 구성되어 있다. 구현한 시스템은 국내 지상파 DMB 교통여행정보 서비스 표준인 TPEG(Transfer Protocol Expert Group) 프레임을 따른다. 본 시스템은 실시간 혼잡교통정보(CTT), 혼잡교통정보(CTT SUM)를 비롯하여 다양한 비실시간 관심지점정보(POI), 안전운전정보(SDI) 등을 저작 및 자동 송출할 수 있도록 설계하였으며, 양질의 콘텐츠를 효율적으로 제작하고 제작한 콘텐츠를 비디오 및 오디오와 함께 안정적으로 송출하는데 중점을 두어 구현하였다. 구현한 시스템은 다양한 수신기와의 실내외 정합실험을 통하여 그 성능을 검증하였으며, 지속적인 업그레이드를 거쳐 현재 방송 서비스에 활용하고 있다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2001년도 Proceeding of KIN-CIN Joint Symposium 2001 on Satellite Navigation/AIS, lntelligence , Computer Based Marine Simulation System and VDR
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• pp.19-25
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• 2001

At present the identification of vessels is still depending on the OOW (Officer Of Wateh) in VTS (Vessel Traffic Service), which is completed by radar, and also by the combination of VHF radio and VHF direction finder. However, with the development of port transportation and economic, this conventional way of identification can't satisfy more and more request for the information that the VTS needs from the vessels. In such a case, the AIS(Automatic Identification System) precept which is based on STDMA (Self-organized Time Division Multiple Access) technique is put forward by IMO (International Maritime Organization). AIS can automatically provide the information, including own ship's identification, type, position, course, speed, and other information to the appropriately equipped coast station and other ships. At the same time it can also automatically monitor and track the nearby ships similarly fitted with AIS. On the basis of describing the whole comprising and the format of transmission information of AIS, this paper mainly studies the key communication techniques in AIS, such as STDMA protocol, net synchronization and GMSK(Gaussian Minimum Shift Keying)technique, and so on. At last this paper briefly introduces the recommendation decided by IMO on forcing the sea-going ships to fixed with AIS equipments, and it continuos with the unexploited potential of AIS if it applies in VTS.

• 오토저널
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• 제14권2호
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• pp.99-109
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• 1992

The response characteristics of a CVT vehicle is investigated numerically by using a Bondgraph model. Simulation result show the continuous behavior of the engine and the speed ratio for the CVT vehicle compared to the discrete behavior of the automatic transmission. Also, the optimal operation of the CVT which is derived from the speed ratio-torque-axial force equation from the previous works. It is found that the speed ratio of CVT has to be controlled corresponding to the optimal CVT ratio that makes the engine run on the optimal operating line.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.164-166
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• 2006

Wien Automatic System Planning Package (WASP) which is used to draw out generation expansion planning applies Dynamic Programming in Korea power system panning. While this package has an advantage that computes annual capacity, it has a disadvantage that can't consider environmental constraints. With the effectuation of the Kyoto Protocol in February, 2005, it is expected that CO2 emission has a severe effect on Korean power system. Therefore, as the most important issue, the generation expansion planning considering environmental constraints is rising in power system. This paper develops a mathematic model including not only generation expansion planning but transmission planning and considering regional supply-demand and environmental constraints, especially CO2 emission, and verifies propriety through the case study.

• 한국항행학회논문지
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• 제26권3호
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• pp.172-178
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• 2022

본 논문은 스마트워터그리드의 핵심기술 중 하나인 수도미터 원격검침(AMR)을 LoRa IoT 네트워크를 이용하여 구현하는 방법에 대한 연구이다. 연구의 주된 내용은 한 대의 PC 서버에서 LoRa 통신으로 다수 세대의 수도미터기 검침 값을 수신받아 데이터베이스에 저장하는 한편 인터넷을 통하여 웹 서버의 클라우드 저장을 하여 사용자의 스마트폰으로 검침 데이터를 열람할 수 있는 네트워크를 구성하는 시스템을 개발하고 테스트 결과를 보인다. 시스템 구성을 위하여 디지털 수도미터기 메인보드의 하드웨어와 펌웨어를 자체적으로 설계 제작하고, PC 서버프로그램으로서 계량데이터운용시스템(MDMS) 프로그램을 비주얼 C#으로, 사용자 스마트폰에서 구동되는 앱 프로그램은 안드로이드 스튜디오로 자체 설계 제작한다. 제작된 각각의 구성을 연결하여 전체 시스템을 실험실 내의 유량 테스트벤치에 장착하여 테스트하여 결과를 보이고, 실제 사용환경 테스트를 위하여 대학 주변의 5곳을 선정하여 전송 거리 테스트를 하여 개발된 시스템이 실사용 현장에 사용 가능함을 보인다. 본 연구결과는 워터그리드에서 충분히 활용할 수 있어 물 사용량 소비패턴, 위치 정보 등을 분석하여 효과적인 물 사용량 관리뿐만 아니라 독거, 치매 어르신 등이 정상적인 생활을 하는지를 추정까지 가능하다는 등 다양한 사회안전망으로도 확대 가능하다.

• 한국항행학회논문지
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• 제24권2호
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• pp.61-66
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• 2020

해양은 지구 표면의 70.8%를 차지하기 때문에 해양산업에서 IoT 기술의 적용은 넓은 영역에 배치된 수많은 장치로부터 다양한 정보를 수집하고 활용하는 것이다. LPWA는 통신 거리가 넓은 특징으로 해양에 배치하기에 매우 적합한 통신이다. 본 논문에서는 전자 어구 실명제를 실행하기 위한 핵심기술인 private LoRa를 기반으로 실해역 성능 거리 실험은 진행하였다. sx1276을 기반으로 한 private LoRa 모듈을 개발하였고, 게이트웨이는 private LoRa로 수신 받은 데이터를 SKT Cat. M1을 이용하여 서버로 데이터를 전송하도록 개발하였다. 해발 599 m에 게이트웨이를 설치하고 25 km, 40 km, 60 km에서 데이터 송수신 실험을 한 결과, 각각 96.1%. 97.1%, 96.2%의 통신 성공률을 보이는 것을 확인할 수 있었다.

• Smart Structures and Systems
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• 제26권5호
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• pp.559-573
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• 2020

One of the powerful data management tools is Building Information Modeling (BIM) which operates through obtaining, recalling, sharing, sorting and sorting data and supplying a digital environment of them. Employing SHM, a BIM in monitoring systems, would be an efficient method to address their data management problems and consequently optimize the economic aspects of buildings. The recording of SHM data is an effective way for engineers, facility managers and owners which make the BIM dynamic through the provision of updated information regarding the occurring state and health of different sections of the building. On the other hand, digital transformation is a continuous challenge in construction. In a cloud-based BIM platform, environmental and localization data are integrated which shape the Internet-of-Things (IoT) method. In order to improve work productivity, living comfort, and entertainment, the IoT has been growingly utilized in several products (such as wearables, smart homes). However, investigations confronting the integration of these two technologies (BIM and IoT) remain inadequate and solely focus upon the automatic transmission of sensor information to BIM models. Therefore, in this composition, the use of BIM based on SHM and IOT is reviewed and the economic application is considered.

• Journal of information and communication convergence engineering
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• 제5권4호
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• pp.389-393
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• 2007

The distribution of donated blood for medical purpose is an area that presents many challenges. In order to establish a comprehensive solution, the current patterns of distribution must be reviewed and problems related to it need to be clearly understood. This paper introduces 'Radio Frequency Identification (RFID) System', as a potential solution to some of the problems which arise in the process of blood supply distribution, and a way to systematically manage the blood supply. For the various possible RFID systems, the reader and tag must be suitable for the purpose of blood distribution. A database has been designed that can recognize tags and objects in a ubiquitous RFID blood distribution system. In this paper, we design the real-time software to control the RFID reader system and transponder, using the EEPROM memory by RFID. The experimental results confirm that the transmission rate of 3.9kbps for RF is 125 KHz. The electric power usage of transponder chip is $100{\mu}W$, with the recognition distance is about 7cm range.

• 한국자동차공학회논문집
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• 제21권3호
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• pp.157-164
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• 2013

A damper clutch in automatic transmission systems has some advantages of fuel economy and dynamic performance. Although a damper clutch operation improves a fuel economy of the vehicles, a positive operation of a damper clutch in a low vehicle speed induces abnormal vibration. This paper analyzed one of reasons for abnormal vibration by a damper clutch operation in low engine speed ranges. A simulation model was designed to confirm the effects of a damper clutch operation under unstable regions of an engine. A theoretical analysis was carried out about an engine operation stability. Simulation was conducted to depict abnormal vibration by a damper clutch operation in unstable regions of an engine performance curve. The effects of an engine operation region for abnormal vibration by a damper clutch was investigated according to the range and the slope of unstable regions. As a result of simulations, a damper clutch operation would be better to avoid an engine unstable regions.

• 한국자동차공학회논문집
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• 제17권3호
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• pp.74-80
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• 2009

The objective of this paper was to investigate the slip rate and the slip frequency number of damper clutch of torque converter in 2.4L passenger vehicle with 5-speed A/T and analyze the effect of slip control and control strategy on driving characteristics and the fuel economy. The newly developed torque converter with the more durable wet friction material and the slip-controlled damper clutch system, the DCC system, was installed, which was easily compatible and amendable of the lock-up clutch of the base system. The vehicle has been tested on the fuel economy modes such as FTP-75, HWFET and NEDC (ECE15+EUDC) driving cycle at chassis dynamometer. The DCC mode (II), of which the control strategy had both the lock-up and the slip-controlled clutch, and the DCC mode (I) with full slip-controlled clutch were compared with the base system with only the lock-up clutch. As the research result, comparison to base system, the fuel consumption of the vehicle with the DCC control (II) was effectively improved by 6.6% and 7.7% on FTP-75 and NEDC mode.