• 제목/요약/키워드: transit

검색결과 2,301건 처리시간 0.025초

아산항 계획 항로에서의 선박 통항의 안전성 평가 검토 (An Investigation for Evaluation of the Safety of the Ship's Transit in the Planned Channel of Asan Port)

  • 이동섭;윤점동;정태권
    • 한국항해학회지
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    • 제18권2호
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    • pp.41-56
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    • 1994
  • This paper was a part of the risk management in planning a channel. It utilized Korea Marine Training & Research Institutes(KMTRI) which Houses a real-time, full-mission shiphandling simulator to examine the safety of the ship's transit in the planned channel of Asan port. 6 competent Captains participated in this study. The vessel modelled was a 60,000-ton ship. The two variables(factors) examined were environ-mental conditions such as flood-and-ebb current condition and day-and-night condition. The two variables were combined to produce four experimental conditions. To evaluate the safety of the environmental conditions, two categories of performance measures were analyzed. They were vessel's proximity to channel boundary and vessel controalbility. The findings regar-ding the effects of environmental conditions were as follows : - Closest Point of Approach(CPA) to channel boundary was enough for 60,000-ton ship to transit th-rough the channel with 99.999% confidence level. - Closest Point of Approach(CPA) to channel boundary further was under against-current condition than under with-current condition. -Vessel controlability was better under against-current condition than under with-current condition. -Vessel controlability was better under inbound transit than under outbound transit.

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A Heuristic Polynomial Time Algorithm for Crew Scheduling Problem

  • Lee, Sang-Un
    • 한국컴퓨터정보학회논문지
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    • 제20권11호
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    • pp.69-75
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    • 2015
  • This paper suggests heuristic polynomial time algorithm for crew scheduling problem that is a kind of optimization problems. This problem has been solved by linear programming, set cover problem, set partition problem, column generation, etc. But the optimal solution has not been obtained by these methods. This paper sorts transit costs $c_{ij}$ to ascending order, and the task i and j crew paths are merged in case of the sum of operation time ${\Sigma}o$ is less than day working time T. As a result, we can be obtain the minimum number of crews $_{min}K$ and minimum transit cost $z=_{min}c_{ij}$. For the transit cost of specific number of crews $K(K>_{min}K)$, we delete the maximum $c_{ij}$ as much as the number of $K-_{min}K$, and to partition a crew path. For the 5 benchmark data, this algorithm can be gets less transit cost than state-of-the-art algorithms, and gets the minimum number of crews.

HR Plate의 경량전철 협폭박스거더교 적용 (Application of Narrow Steel Box Girder Bridge of Light Rail Transit with HR Plate)

  • 박대수;황낙연;정경섭;이성행
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.365-375
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    • 2006
  • The HR Plates made hot rolled coils is lower than general structural steel plates in price. No difference between general steel plates and HR Plates with thickness up to 22mm are found in most characters such as cutting operation, fabrication and even welding. It can be concluded that HR Plates with thickness up to 22mm can be applied to flanges and webs of any girders as well as longitudinal ribs, longitudinal and vertical stiffeners of steel bridges appropriately. To increase the demand of HR Plates with thickness up to 22mm, it is necessary that HR Plates is applicable to full member in steel bridge including main girder.In this study, availabilities of the narrow steel box girder of light railway transit with HR Plate width as a main member are discussed. For application of HR Plate to steel bridge with 50m span or more, new support systems in three types are presented. Computational analysis is performed in 15 bridge models of light railway transit with beam element and plate element. As a analysis results, three models in light railway transit are presented. We finally come to the conclusion that HR Plates can be apply to narrow steel box girder in the light railway transit.

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Observation of transiting exoplanet TrES-2b at Maidanak Observatory in Uzbekistan

  • 양윤아;이상각;강원석
    • 천문학회보
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    • 제36권1호
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    • pp.28.1-28.1
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    • 2011
  • We observed the transiting exoplanet, TrES-2b, with 1.5m telescope at Maidanak Observatory in Uzbekistan. We observed TrES-2 system for six nights, which contained two orbital periods of the planet. Therefore, we obtained the entire light curve of TrES-2b, which covered not only the whole primary transit containing both ingress and egress part, but also non-transit region. We used both R and Y band filters. Especially, Y filter is used first for transit observation and covers relatively longer wavelength ($1.02{\mu}m$ of center wavelength), to provide the light curve less affected by limb darkening. By fitting best model light curve for the obtained one, we determined these observables, transit depth, transit length, and planet's orbital period, which led to the determination of five physical parameters, stellar radius R*, stellar mass M*, inclination i, semi-major axis a, and planetary radius Rp. We will discuss of these results.

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스마트카드 빅데이터를 이용한 서울시 지역별 대중교통 이동 편의성 분석 (Analysis of Regional Transit Convenience in Seoul Public Transportation Networks Using Smart Card Big Data)

  • 문현구;오규협;김상국;정재윤
    • 대한산업공학회지
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    • 제42권4호
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    • pp.296-303
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    • 2016
  • In public transportation, smart cards have been introduced for the purpose of convenient payment systems. The smart card transaction data can be utilized not only for the exact and convenient payment but also for civil planning based on travel tracking of citizens. This paper focuses on the analysis of the transportation convenience using the smart card big data. To this end, a new index is developed to measure the transit convenience of each region by considering how passengers actually experience the transportation network in their travels. The movement data such as movement distance, time and amount between regions are utilized to access the public transportation convenience of each region. A smart card data of five working days in March is used to evaluate the transit convenience of each region in Seoul city. The contribution of this study is that a new transit convenience measure was developed based on the reality data. It is expected that this measure can be used as a means of quantitative analysis in civil planning such as a traffic policy or local policy.

경량전철 전력시스템 용량선정에 대한 검토 (A review on the capacity selections about power system of Light Rail Transit)

  • 이재봉;오성효;송지훈
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.390-400
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    • 2011
  • Light rail are being constructed in cities have populations of mare than 700 thousand in the country as well as many cities in the world as an environmental and a low caron public transit. This paper reviews the capacity selections of electric power system about Light rail transit according to rail, vehicles, operation conditions.

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도시철도 유지보수체계 표준화 연구 (A Study of the Standardization of the Urban Transit Maintenance System)

  • 박기준;안태기;이호용;김길동;한석윤
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.358-364
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    • 2004
  • The standardization of the urban transit maintenance system consists of BOM System, maintenance parts code system, and accident/trouble code system standardization. This paper is described only the result of BOM System, maintenance parts code system, and accident/trouble code system standardization. The results of standardization are using urban transit maintenance IT system and apply Expert System, RAMS System, and DATABASE contents of various kinds.

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분당선 도시철도 운전모드와 ATC 시스템 동작알고리즘에 관한 연구 (A Study on Bundang-line Urban Transit Operation Mode and Operation Algorithm Analysis of an ATC System)

  • 김종기;이기서
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.1247-1252
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    • 2004
  • ATC(Automatic Train Control) system employed in Bundang urban transit is operated in accordance with automatic blocking equipment. Using AF(Audio Frequency) track circuits installed at a block section, the block signal is automatically controlled and the safety of train operation is supported. In this paper, we investigate the operation mode of bundang urban transit and analyze the operation algorithm of ATC on-board system.

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경량전철 선로설계기준에 관한 연구 (A Study on Track Design Criteria of Light Rail Transit System)

  • 이안호;이덕영
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(II)
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    • pp.135-140
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    • 2003
  • Recently Light Rail Transit(LRT) systems, especially full automatic systems are strongly issued by many provinces and major cities due to it's own characteristic for economical, environmental and sufficient transportation capacity. But LRT design criteria should be modified according to Rolling Stock's properties. -size, arrangement of bogie and wheel, power of traction motor etc, This thesis suggest for basic standard design criteria of Rubber Tired Light Rail Transit system.

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철도차량을 위한 선형유도전동기의 설계 (Design of Linear Induction Motet (LIM) for Transit Applications)

  • 박도영;김봉섭;김동성;남용윤
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 특별세미나 특별세션
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    • pp.181-188
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    • 2006
  • Outline of design procedures of Linear Induction Motor (LIM) for transit vehicle applications are presented. The design steps are based on the classical design method. Constrains specific for transit applications are discussed. Heuristic data obtained from the various LIMs are utilized to streamline the presented design steps.

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