• 제목/요약/키워드: Speed management

검색결과 2,102건 처리시간 0.039초

Survey Methodology for Estimating Patronage of High-Speed Rail in Korea

  • Lee, Jin-Sun;Nam, Doo-Hee
    • International Journal of Railway
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    • 제4권2호
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    • pp.29-33
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    • 2011
  • High-speed rail study needs to focus on passenger movements as a key element of the planning process. A particular challenge is obtaining comprehensive information on high-speed rail passenger movements. A national preference stated survey was conducted from October to November of 2011 to meet this challenge through direct personal interviews of travelers between Seoul and Busan (the so called Kyung-Bu corridor). Over 40 interviewers were hired and trained to conduct personal interviews at several stations along locations within Kyung-Bu Seoul and Busan corridor. A total of 4,550 travelers were interviewed, furnishing an extensive database on high-speed rail passenger movements. The methodology and procedure employed to collect the national data for Korean high-speed train KTX are described. Specific issues investigated include survey design, questionnaire and strategy. Lessons learned from the high-speed rail passenger movement study provide insights for other countries contemplating similar high-speed rail studies.

내부점방법을 위한 초마디 열촐레스키 분해의 실험적 고찰 (Experimental Study on Supernodal Column Choleksy Factorization in Interior-Point Methods)

  • 설동렬;정호원;박순달
    • 경영과학
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    • 제15권1호
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    • pp.87-95
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    • 1998
  • The computational speed of interior point method depends on the speed of Cholesky factorization. The supernodal column Cholesky factorization is a fast method that performs Cholesky factorization of sparse matrices with exploiting computer's characteristics. Three steps are necessary to perform the supernodal column Cholesky factorization : symbolic factorization, creation of the elimination tree, ordering by a post-order of the elimination tree and creation of supernodes. We study performing sequences of these three steps and efficient implementation of them.

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내부점 선형계획법의 밀집열 분할에 대하여 (On dence column splitting in interial point methods of linear programming)

  • 설동렬;박순달;정호원
    • 경영과학
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    • 제14권2호
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    • pp.69-79
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    • 1997
  • The computational speed of interior point method of linear programming depends on the speed of Cholesky factorization. If the coefficient matrix A has dense columns then the matrix A.THETA. $A^{T}$ becomes a dense matrix. This causes Cholesky factorization to be slow. We study an efficient implementation method of the dense column splitting among dense column resolving technique and analyze the relation between dense column splitting and order methods to improve the sparsity of Cholesky factoror.

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가입자 통신망을 위한 대역 할당 알고리즘 성능 분석 (Performance Evaluation of a Bandwidth Allocation Algorithm of E-PON)

  • 주운기;이상우;김찬;권율
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2005년도 추계학술대회 및 정기총회
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    • pp.361-364
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    • 2005
  • As increasing the Internet traffic, many researches on access network are reported for end-to-end high-speed broadband network, where E-PON(Ethernet-Passive Active Network) is one of reasonable candidate fur the network with respect to cost and bandwidth utilization. For the high-speed access network, E-PON need an efficient bandwidth allocation method. This paper suggests a WFA(Water-Filling Allocation) algorithm for the efficient bandwidth allocation with various simulation test.

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F-AHP 평가수법을 적용한 고속전철 안전성의 평가 (Fuzzy-AHP Estimation Technique for Korea High Speed Railway Safety Management)

  • 박태근;박춘수;서승일
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.328-333
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    • 2004
  • Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has ben improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

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F-AHP평가수법을 적용한 고속전철 안전성의 평가 (Fuzzy-AHP Estimation Technique for Korea High Speed Railway Safety Management)

  • 박태근;박춘수;서승일
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(I)
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    • pp.192-198
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    • 2003
  • Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has been improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

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고속전차선로 설계자동화를 위한 자재관리 D/B의 설계 및 개발 (A Development of Automatic materials management D/B for High-speed catenary system)

  • 이기원;김주락;창상훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.263-265
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    • 2002
  • This paper presents a design method of database to manage materials having hierarchical structure on Kyungbu high-speed catenary system. Through this method, the automatic management software was developed. The software can get to find out assemblies as well as single fittings used in a section.

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보관작업장 사고방지 예방에 관한 연구: 렉 작업장을 중심으로 (A Study on Cargo Picking Safety Work: Focusing on Rack Work Place)

  • 정병현;김기홍
    • 대한안전경영과학회지
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    • 제24권3호
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    • pp.23-28
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    • 2022
  • Rack is a place to store products. Workers pick products from rack storage. After picking up, workers move to another location by forklift. Driving speed, worker condition, and number/frequency of operation is responsible for forklift accidents. When an accident occurs, products get damaged. Therefore, it is important to prevent one. As the research result, To prevent forklift accidents, the minimum order quantity, the minimum number of operations, and low speed operation are required.

유비쿼터스 기술을 위한 고속철도상 Pre-Stressed Concrete(PSC) 교량받침의 누적수평이동거리에 관한 수치해석 (Numerical Analysis of Accumulated Sliding Distance of Pre-Stressed Concrete (PSC) Bridge Bearing for High-Speed Railway for Ubiquitous Technology)

  • 오순택;이동준;이홍주;정신효
    • 디지털산업정보학회논문지
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    • 제11권1호
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    • pp.9-18
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    • 2015
  • Numerical analysis of PSC box bridge bearings for high speed KTX train vehicles has been carried out as a virtual simulation for Ubiquitous Technology. Improved numerical models of bridge, vehicle and interaction between bridge and train are considered, where bending and torsional modes are provided, whereas the exist UIC code is applied by the simplified HL loading. Dynamic and static analysed results are compared to get Dynamic Amplification Factors (D. A. F.) for maximum deflections and bending stresses up to running speed of 500 km/h. Equation from the regression analysis for the D. A. F. is presented. Sliding distance of the bearings for various KTX running speeds is compared with maximum and accumulated distances by the dynamic behaviors of PSC box bridge. Dynamic and static simulated sliding distances of the bearings according to the KTX running speed are proved as a major parameter in spite of the specifications of AASHTO and EN1337-2 focused on the distance by temperature variations.

Design and implementation of a GIS-based accident management system using tracking technique

  • Niaraki Abolghasem Sadeghi;Kim Kye-Hyun
    • 한국공간정보시스템학회 논문지
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    • 제8권2호
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    • pp.1-11
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    • 2006
  • This paper addresses a GIS (Geographic Information System) based system in order to reduce the rate of public transportation accidents occurring in Iranian roads network. Over the years, the road accidents are a major issue throughout the world. Today, particular consideration is given to those technologies which can lead to diminish on the number of critical incidents. One of the main factors resulting in accidents and fatalities rates growth is the speed violation of buses in Iranian road network. The conventional speed controlling approach in Iran based on the Tachograph which records vehicle's speed, time, and stoppage in the mechanical processing has many problems. Hence, this research is intended to design and implement a GIS-based system to manage road accident of Bus transportation system using offline tracking system. This was accomplished using a GIS-based technique that encompasses three steps. The first step is developing a GIS-based accident system. The second step includes designing and applying a tracking system inside 90 buses for recording Bus information for speed controlling. Lastly, by using mentioned system in police center, the illegal drivers' punishment would be considered properly. Overall, this system has been successfully applied in this work. Therefore, the police and transportation office are able to control and make policy to diminish the number of accident. It is anticipated that online tracking system through the Web GIS would be utilized In this system in the near future.

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