• 제목/요약/키워드: loss system

검색결과 7,512건 처리시간 0.037초

CVT 시스템 효율을 고려한 변속 제어 (Ratio Control of CVT by Considering the CVT System Efficiency)

  • 류완식;김현수
    • 한국자동차공학회논문집
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    • 제14권4호
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    • pp.157-163
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    • 2006
  • A modified ratio control algorithm is proposed for the improvement of the fuel economy for a metal belt CVT. In the modified ratio control algorithm, the CVT ratio is controlled to operate the engine on the optimal operation region which provides the best efficiency from the view point of the overall efficiency of the engine-CVT system. In order to construct the modified ratio map, the CVT system loss model is used by assuming that the all the loss is attributed to the torque loss. It is found from the simulation results that the fuel economy by the modified ratio control algorithm is improved by 5.5 percents compared with the existing ratio control.

전기철도차량 이선 현상 검측을 위한 TEO 및 STFT 신호처리기법 적용에 관한 연구 (A Study on the Application of TEO and STFT Signal Processing Techniques for Detection of Electric Railway Contact Loss)

  • 정노건;박철민;이재범;박영;신승권
    • 전기학회논문지
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    • 제67권11호
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    • pp.1530-1535
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    • 2018
  • In this paper, A technique for detecting contact loss at the input power of a railway vehicle has been studied when the contact loss occurs in the feed system. The impedance of the actual railway line was applied to the modeling of the feed system, and modeling was performed based on the performance of the electric railway vehicle. The input voltage and current of the railway vehicle through modeling were analyzed by applying TEO and STFT signal processing technique.

냉매충전량이 초임계 이산화탄소 사이클의 냉방성능에 미치는 영향에 대한 연구 (Effects of Refrigerant Charge Amount on the Cooling Performance of a Transcritical $CO_{2}$ Cycle)

  • 조홍현;류창기;김용찬;심윤희
    • 설비공학논문집
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    • 제17권5호
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    • pp.410-417
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    • 2005
  • The cooling performance of a transcritical $CO_{2}$ cycle varies significantly with a variation of refrigerant charge amount. In this study, the performance of the $CO_{2}$ system was measured and analyzed by varying refrigerant charge amount at a standard test condition. Besides, the losses of the major components in the $CO_{2}$ system were estimated by evaluating entropy generation with refrigerant charge amount. The losses in the expansion device and the gascooler show the major portion of the total loss. For undercharging conditions, the expansion loss dominates the overall system performance, while the gascooler loss increases significantly with an increase of refrigerant charge amount.

Applications of Seismic Disaster Simulation Technology on Risk Management

  • Yeh, Chin-Hsun
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2010년도 정기 학술발표대회
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    • pp.16-24
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    • 2010
  • This paper introduces the applications of Taiwan Earthquake Loss Estimation System (TELES), which is developed by the National Center for Research on Earthquake Engineering (NCREE). Seismic disaster simulation technology (SDST) integrates geographical information system to assess the distribution of ground shaking intensity, ground failure probability, building damages, casualties, post-quake fires, debris, lifeline interruptions, economic losses, etc. given any set of seismic source parameters. The SDST may integrate with Taiwan Rapid Earthquake Information Release System (TREIRS) developed by Central Weather Bureau (CWB) to obtain valuable information soon after large earthquakes and to assist in decision-making processes to dispatch rescue and medical resources more efficiently. The SDST may also integrate with probabilistic seismic source model to evaluate various kinds of risk estimates, such as average annual loss, probable maximum loss in one event, and exceeding probability curves of various kinds of losses, to help proposing feasible countermeasures and risk management strategies.

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이동통신대역의 경로손실 모델 설정에 관한 연구 (A Study on the Path Loss Modeling for Mobile Cellular System)

  • 박경태;정인성;김동일
    • 한국전자파학회논문지
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    • 제13권7호
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    • pp.726-731
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    • 2002
  • 이 논문은 이동전화 기지국 설치를 위한 전파 환경 분석을 목적으로 하고 있다. 대상지역의 최대거리는 150 km, 면적은 6000 $\textrm{km}^2$에 이르며, 총 5개의 기지국에서 이동전화 서비스를 할 수 있도록 하기 위하여 필드 측정을 하였다. 이렇게 측정한 전파환경을 하타(Hata)모델과 오쿠무라(Okumura)모델로 근사시켜 경로손실 예측모델을 선정하였다. 필드테스트 분석 결과, 측정된 지역의 전파환경 경로손실은 농촌지역과 도시근교지역의 중간 지역의 하타(Hata) 모델로 근사할 수 있다는 것을 알 수 있었다.

구조 진동 시스템을 이용한 흡차음재 음향 성능 실험시 공기 층 삽입의 효과 (The Effect of Air gap Insertion in Test Acoustic Performance of Sound Barrier using Structural Vibration System)

  • 신재성;강연중;성명호;김현석
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집B
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    • pp.646-650
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    • 2001
  • In this paper, it is presented that the effect of air gap insertion in testing the transmission loss of sound barrier using structural vibration system. In this study, we use the APAMAT based on the structure-borne-noise. The measured results show that air gap insertion improves transmission loss as results of test based on the air-borne-noise. The measured results are compared with the predicted transmission loss using the transfer matrix method. The predicted results were found to be in reasonable agreement with measured results.

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RFID를 이용한 분실방지 시스템의 설계와 구현 (Design and Implementation of the Loss Preventing System using RFID)

  • 이용희;김현기;송호정
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2008년도 추계학술발표대회
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    • pp.920-923
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    • 2008
  • 본 논문에서는 RFID를 이용한 분실방지 시스템을 개발하였다. 개인의 귀중한 소지품이 절도 당하는 것을 사용자에게 경보를 알려줌으로서 분실된 소지품의 품목을 알 수 있게 해 준다 또한 대처를 즉시 할 수 있도록 해주는 시스템을 설계 및 구현하였고, 실제 필드 테스트를 통해 시스템의 안전성 및 타당성을 검증하였다.

나일론 6 섬유의 감량가공 및 특성 연구 (A Study on the Weight Loss Treatment and Characteristics of Nylon 6 Fiber)

  • 임성찬;이현우;이현재;원종성;진다영;이승구
    • 한국염색가공학회지
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    • 제27권3호
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    • pp.175-183
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    • 2015
  • Weight loss treatment of a fiber leads an improvement of its handle and drape properties. Hydrolysis of a fiber is commonly known as a method to reduce its weight of 5-40%. Most of the studies on the weight loss treatment are mainly based on polyester fibers and there has been almost no study on the weight reduction of nylon fibers. In this study, however, in order to develop a use of nylon 6 fiber for the industrial applications such as toothbrush, underwear, carpet and more, weight loss treatment of a nylon 6 fiber was carried out. Under various treatment conditions, morphological analysis were done to observe the change in the structure of the surface and analysis. From the observation of formic acid treated nylon 6 fiber, there were many etched and deformed morphologies. Thermal and crystalline properties were analyzed to find the changes in the crystal structure caused by the weight loss treatment. There were little differences in the crystalline properties of nylon 6 fiber by formic acid treatment. Tensile strength of nylon 6 fiber decreases with acid concentration. The FITR peak intensity of the amide bond decreases with formic acid concentration.

Development of On-site Heat Loss Audit and Energy Consulting System for Greenhouse

  • Kwon, Jin Kyung;Kang, Geum Choon;Lee, Seong Hyun;Sung, Je Hoon;Yun, Nam Kyu;Moon, Jong Pil;Lee, Su Jang
    • Journal of Biosystems Engineering
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    • 제38권4호
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    • pp.287-294
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    • 2013
  • Purpose: Greenhouses for a protected horticulture covered with a plastic or glass are easy to have weakness in a heat loss by deterioration, damage, poor construction, and so on. To grasp the vulnerable points of heat loss of the greenhouses is important for heating energy saving. In this study, an on-site heat loss audit and energy consulting system were developed for an efficient energy usage of a greenhouse. Method: Developed system was mounted with infrared thermal and visual cameras to grasp the heat loss from the greenhouse quickly and exactly, and a trial calculation program of heating load of greenhouse to provide farmers with the information of heating energy usage. Results: Developed system could print out the reports about the locations and causes of the heat losses and improvement methods made up by an operator. The mounted trial calculation program could print out the information of the period heating load and fuel cost according to the conditions of greenhouse and cultivation. The program also mounted the databases of the information on the 13 horticultural energy saving technologies developed by the Korea Rural Development Administration and simple economic analysis sub-program to predict the payback period of the technologies. Conclusion: The developed system was expected to be used as the basic equipment for an instructors of district Agricultural Technology and Extension Centers to conduct the energy consulting service for the farmers within the jurisdiction.

신뢰성 있는 단방향 데이터 전송 시스템 설계 (Design of a Reliable Data Diode System)

  • 김동욱;민병길
    • 정보보호학회논문지
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    • 제26권6호
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    • pp.1571-1582
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    • 2016
  • 단방향 전송 기술에서 해결해야 할 이슈들 중에 한 가지는 TCP 기반의 데이터 전송에서 발생하는 패킷 손실을 줄이는 것이다. 잘 알려진 에러 수정 기법들을 활용해서 패킷 손실을 줄일 수 있다. 하지만, 기존의 여러 기법들을 활용한다고 하더라도, 링크 에러와 버퍼 오버플로우에 의한 패킷 손실은 여전히 발생할 수 있다. 본 논문에서는 신뢰성 있는 단방향 데이터 전송 시스템(RED, REliable Data diode)을 제안한다. RED는 기존의 단방향 전송 기술과 마찬가지로 TCP 기반의 데이터 전송을 지원하기 위해 TCP 프록시 기법을 활용한다. RED 송신시스템은 TCP 패킷의 지연 전송을 활용하여 버퍼 오버플로우에 의한 패킷 손실을 줄일수 있다. 또한, RED 송신시스템은 패킷의 중요도 및 여유 자원을 고려하여, RED 수신시스템에게 다수의 동일한 패킷을 복제 및 전송함으로써, 단방향 전송 링크에서의 링크 에러에 의한 패킷 손실을 줄일 수 있다.