• 제목/요약/키워드: Congestion

검색결과 2,641건 처리시간 0.207초

『동의보감(東醫寶鑑)』에 보이는 단계담음론(丹溪痰飮論)의 의사학적(醫史學的) 고찰(考察) (A medical historical study of Dan-kyei's congestion theory mentioned in 『DongEuiBoGam』)

  • 소진백
    • 한국의사학회지
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    • 제15권1호
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    • pp.147-182
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    • 2002
  • By studing the congestion theory of Choo Dan-kyei mentioned in "DongEuiBoGam", I have reached following conclusions. 1. Dan-kyei's congestion theory influenced greatly on "DongEuiBoGam". The congestion theory of "DongEuiBoGam" is built up with several theories centering round on Dan-kyei's theory and Huh-Jun's own opinion in addition. 2. Dan-kyei's congestion theory has given theoretical foundation to the classification and diagnosis of congestion reported in "DongEuiBoGam"-Congestion Chapter. 3. Dan-kyei's congestion theory offers many examples of symptoms reported in "DongEuiBoGam"-Congestion Chapter. It's shown well through outer symptoms, several congestion disease, congestion mass, and "congestion never sudden death", etc. 4. Dan-kyei's congestion theory has influenced greatly on treatment of congestion reported in "DongEuiBoGam"-Congestion Chapter, and it's well shown through spewing method, grand method in congestion treatment and common medicine of congestion, etc. 5. Dan-kyei's congestion theory offers variety of treating methods to symptoms caused by congestion reported in "DongEuiBoGam". It's shown variously through upper stomachache, stomachache, back pain, side pain, "San", joint pain, Summer disease, internal injury, cough and morning sickness, etc.. 6. Dan-kyei's congestion theory has factors that could be operated to common diseases of mordern people. They can be classified as food congestion, alcohol congestion, obstruction congestion and Qi congestion, and they are clinically very efficient.

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A Study on Estimate Model for Peak Time Congestion

  • Kim, Deug-Bong;Yoo, Sang-Lok
    • 해양환경안전학회지
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    • 제20권3호
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    • pp.285-291
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    • 2014
  • This study applied regression analysis to evaluate the impact of hourly average congestion calculated by bumper model in the congested area of each passage of each port on the peak time congestion, to suggest the model formula that can predict the peak time congestion. This study conducted regression analysis of hourly average congestion and peak time congestion based on the AIS survey study of 20 ports in Korea. As a result of analysis, it was found that the hourly average congestion has a significant impact on the peak time congestion and the prediction model formula was derived. This formula($C_p=4.457C_a+29.202$) can be used to calculate the peak time congestion based on the predicted hourly average congestion.

멀티미디어 서비스 품질의 전송 효율성 향상을 위한 연구 (A Study on the Improvement of Transmission Efficiency for Multimedia Service Quality)

  • 문호선;하동문;김용득
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(5)
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    • pp.83-86
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    • 2002
  • In this paper while a router is routing all packet to the next hop, it inspects whether there is congestion on this current hop router or not and if the router discovers that it has some congestion, it informs that the packet is experienced to congestion. The packet arrived to next hop including some information about the congestion is processed first and it has wider bandwidth than another packet The amount of congestion is recorded to the DS field of IP header by congestion experience level. In the next hop when the packet including the congestion information is routed, the standard packet dropping ratio of the current router is changed in proportion to congestion experience that is recorded in IP header on of that. When the packet that has experienced congestion before is arrived, the router extends the drop threshold value not to drop the packet. It mean that transferring the audio or video stream, if the packet is already experienced the congestion in another hop, the router can provide the better service quality about 15∼25% than another.

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Optimal Siting of UPFC for Reducing Congestion Cost by using Shadow Prices

  • Lee, Kwang-Ho;Moon, Jun-Mo
    • KIEE International Transactions on Power Engineering
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    • 제11A권4호
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    • pp.21-26
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    • 2001
  • As competition is introduced in the electricity supply industry, congestion becomes a more important issue. Congestion in a transmission network occurs due to an operating condition that causes limit violations on the transmission capacities. Congestion leads to inefficient use of the system, or causes additional costs (Congestion cost). One way to reduce this inefficiency or congestion cost is to control the transmission flow through the installation of UPFC (Unified Power Flow Controller). This paper also deals with an optimal siting of the UPFC for reducing congestion cost by using shadow prices. A performance index for an optimal siting is defined as a combination of line flow sensitivities and shadow prices. The proposed algorithm is applied to the sample system with a condition, which is concerning the quadratic cost functions. Test results show that the siting of the UPFC is optimal to minimize the congestion cost by the proposed algorithm.

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항만투자의 유효성 측정방법: congestion모형 접근 (A Measurement Way on the Effectiveness of Port Investment: Congestion Model Approach)

  • 박노경
    • 한국항만경제학회지
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    • 제19권2호
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    • pp.33-53
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    • 2003
  • The purpose of this paper is to investigate the effectiveness of port investemnt which is one of the important elements for measuring the port efficiency by using congestion approach of DEA(Data Envelopment Analysis). Congestion is said to be present when increases in inputs result in input reductions. Congestion approach takes the forms of weak input disposability and strong input disposability. Empirical analysis by using congestion approach in this paper identified inefficiencies in the inputs including port investment, and indicated inefficient ports like the ports of Sokcho, Gunsan, Pohang, and Seoguipo which shows the large amount of slacks with congestion especially in terms of port investment. Therefore these ports should examine the reason about the inefficiency of port investment. The main policy implication based on the findings of this study is that The Ministry of Maritime Affairs & fisheries in Korea should introduce congestion approach when the amount of port investment to each port is decided.

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Comparative Study of Two Congestion Management Methods for the Restructured Power Systems

  • Manikandan, B.V.;Raja, S. Charles;Venkatesh, P.;Mandala, Manasarani
    • Journal of Electrical Engineering and Technology
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    • 제6권3호
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    • pp.302-310
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    • 2011
  • Congestion management is one of the most challenging tasks of a system operator to ensure the operation of transmission system within operating limits. In this paper, cluster/zone method and relative electrical distance (RED) method for congestion management are compared based on the considered parameters. In the cluster/zone method, rescheduling of generation is based on user impact on congestion through the use of transmission congestion distribution factors. In the RED method, the desired proportions of generations for the desired overload relieving are obtained. Even after generation rescheduling, if congestion exists, load curtailment option is also introduced. Rescheduling cost, system cost, losses, and voltage stability parameter are also calculated and compared for the above two methods of congestion management. The results are illustrated on sample 6-bus, IEEE 30-bus, and Indian utility 69-bus systems.

빅데이터 분석을 활용한 공항 혼잡도 분석 - 김포공항 사례를 중심으로 - (Airport Congestion Analysis with Big Data Analysis - The Case of Gimpo Airport -)

  • 김진아;김진기
    • 한국항공운항학회지
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    • 제28권2호
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    • pp.36-46
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    • 2020
  • This study is designed to help customers use more comfortable airports by predicting congestion and congestion times by identifying the traffic routes of passengers in the airport building by day of the week and time by using Wi-Fi sensor collectors, one of the IoT technologies. Analysis of passenger traffic analysis data showed that the most congested time zones were from noon. to 2p.m. for all facilities, which could be used to improve major facilities. Regression analysis of factors affecting congestion found that self-check-in reduces congestion and check-in counters increases congestion. These findings will provide important implications for operations, including congestion management at airports.

항만투자의 유효성 분석 - congestion모형 접근 - (A Study on the Effectiveness of Port Investment: Congestion Model Approach)

  • 박노경
    • 한국항만경제학회:학술대회논문집
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    • 한국항만경제학회 2003년도 정기학술대회지
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    • pp.221-242
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    • 2003
  • The purpose of this paper is to investigate the effectiveness of port investment which is one of the important elements for measuring the port efficiency by using congestion approach of DEA(Data Envelopment Analysis). Congestion is said to be present when increases in inputs result in ouput reductions. Congestion approach takes the forms of weak input disposability and strong input disposability. Empirical analysis by using congestion approach in this paper identified inefficiencies in the inputs including port investment, and indicated inefficient ports like the ports of Sokcho, Gunsan, Pohang, and Seoguipo which shows the large amount of slacks with congestion especially in terms of port investment. Therefore these ports should examine the reason about the inefficiency of port investment. The main policy implication based on the findings of this study is that The Ministry of Maritime Affairs & Fisheries in Korea should introduce congestion approach when the amount of port investment to each port is decided.

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유비쿼터스 컴퓨팅 환경에서 단말의 이동성을 지원하기 위한 DCCP 기반의 혼잡 제어 정책 (DCCP based Congestion Control Scheme to support Mobility of Devices on Ubiquitous Computing Environment)

  • 박시용;김성민;이태훈;정기동
    • 한국정보과학회논문지:정보통신
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    • 제33권1호
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    • pp.59-75
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    • 2006
  • 본 논문에서는 유비쿼터스 컴퓨팅 환경에서 단말들의 이동성에 따른 네트워크의 혼잡 상태를 제어 할 수 있는 적응적인 혼잡 제어 기법을 제안한다. 제안하는 혼잡 제어 기법은 무선망의 특성상 발생할 수 있는 패킷 에러와 혼잡에 의한 패킷 손실을 구분하기 위해서 역 혼잡 회피 단계 및 혼잡 제어 시에 발생하는 비효율적인 대역폭 이용율을 최소화 할 수 있는 슬로우 스톱 단계를 기존의 혼잡 제어 정책에 새롭게 추가한다. 본 논문에서 제안하는 혼잡 제어 정책은 제 3의 전송 계층 프로토콜이라고 불리우는 DCCP(Datagram Congestion Control Protocol)를 기반으로 설계되었고 리눅스 커널 상에서 구현하였다. 제안된 혼잡 제어 정책은 기존의 혼잡 제어 정책보다 적응성 있게 혼잡 상태를 제어하며, 실험 결과 무선에서뿐만 아니라 유선에서도 우수한 대역폭 이용율을 보였다.

위성 랜덤 액세스 채널에서 Bursty 트래픽의 신속한 전송을 위한 빠른 혼잡 제어 기법 (Fast Congestion Control to Transmit Bursty Traffic Rapidly in Satellite Random Access Channel)

  • 노홍준;이윤성;임재성;박형원;이호섭
    • 한국통신학회논문지
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    • 제39C권11호
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    • pp.1031-1041
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    • 2014
  • 본 논문은 복제 패킷을 사용하는 위성 랜덤 액세스 채널에서 bursty 트래픽을 안정적으로 전송하기 위한 트래픽 부하 제어 기법으로 FCC (Fast Congestion Control)을 제안한다. 위성 랜덤 액세스 채널에서 순간적으로 발생하는 bursty 트래픽은 그 양이 많을 경우 충돌 확률로 인하여 backlogged 트래픽이 다수 발생할 수 있다. FCC는 access probability를 통해 트래픽 부하를 제어하며, backlogged 트래픽의 양을 추정한다. 또한 backlogged 트래픽이 최대 처리량에 해당하는 트래픽 부하를 넘어설 경우 빠르게 congestion 상태로 전환한다. Congestion 상태에서는 backlogged 트래픽이 우선적으로 처리되며, 새로 유입되는 트래픽은 congestion 상태가 지속되는 동안 채널에 접속하지 않고 대기하다가 congestion 상태가 종료되는 시점에 채널에 유입된다. Congestion 상태에서 backlogged 트래픽은 신속한 전송을 보장받기 때문에 지연 시간이 단축된다. 따라서 FCC는 긴급성이 요구되는 군 트래픽에 매우 적합한 기술이다. 본 논문은 모의실험을 통해 기존 기법 대비 제안 기법의 우수성을 확인하였다.