• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.393-396
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• 2005

Due to the fast growing rate of the global container trade, every major port is under the pressure of meeting the projected capacity demand. As a result, alternative solutions have been sought for improving capacity and meeting the growing demand for container storage area and terminal capacity. Moreover, material handling process re-engineering is now a critical issue for logistics and supply chain managers of airline, shipping lines, terminal and warehousing enterprises around the world. Therefore, the purpose of this paper is to develop the 3D simulator for executing performance valuation of port transportation systems. The developed 3D simulator system is to measure the effectiveness of the proposed total system and compare it with existing practices. The performance analysis variables are also defined for these comparisons

• International Journal of Internet, Broadcasting and Communication
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• 제7권2호
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• pp.90-95
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• 2015

This paper describes IEC 61727 standard of Photovoltaic (PV) systems -Characteristics of the utility interface. IEC 61727 standard tests include utility compatibility and personnel safety and equipment protection of PV inverter performance functions. Especially utility compatibility part includes test items of 1) voltage, current and frequency, 2) normal voltage operating range, 3) flicker, 4) DC injection, 5) normal frequency operating range, 6) harmonics and 7) waveform distortion, 8) power factor of PV inverter. Also personnel safety and equipment protection part includes test items 1)loss of utility voltage, 2)over/under voltage and frequency, 3)Islanding protection, 4)response to utility recovery, 5)earthing, 6)short circuit protection, 7)Isolation and switching of PV inverter. In this paper, each item of IEC 61727 standard test is studied and analyzed and finally full tested by PV inverter performance function.

• 교통기술과정책
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• 제8권4호
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• pp.35-44
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• 2011

• 교통기술과정책
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• 제9권2호
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• pp.77-85
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• 2012

• 항공우주기술
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• 제10권1호
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• pp.20-29
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• 2011

KSLV-I 상단부 이송 항목 중 KARI가 직접 이송하는 VEB 조합체는 진동 및 충격에 민감한 전기 전자 부품과 유공압 부품을 다수 포함하고 있어, 이송에 특별한 주의가 요구된다. VEB 조합체 이송 요구 조건을 만족시키기 위해 환경제어장치가 구비된 이송 컨테이너를 제작하였다. 제작한 이송 컨테이너의 성능 검증 및 이송 조건(이송 속도, 이송 경로 등) 타당성 확인을 위해 엔지니어링모델을 이용한 4회의 이송 시험을 수행한 바 있다. 본 논문에서는 기존의 VEB 조합체 이송 이력과 발사2호기 VEB 조합체 이송 개요 및 결과 등을 정리하였다.

• 산업공학
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• 제16권2호
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• pp.174-184
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• 2003

This paper addresses a fleet operation planning problem for a static freight container transportation system in which all the transportation requirements are predetermined at the beginning of a planning horizon. In the transportation system under consideration, a number of loaded containers are to be moved between container storage yards. An optimal fleet planning model is used to determine the minimum number of vehicles required. Based on the results from the optimal model, a tabu-search based algorithm is presented to perform a given transportation requirements with the least number of vehicles. The performance of the new procedure is evaluated through some experiments in comparison with two existing methods, and the it is found that our procedure produces good-quality solutions.

• 전기학회논문지
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• 제65권3호
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• pp.520-525
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• 2016

In this paper, Characteristic of power conversion unit of a railway vehicles according to contact loss in feeding system that applied impedance of rigid conductor is analyzed. It applied impedance of rigid bar in modeling of electric railway system. Railway vehicles are performed of modeling based on the performance of the electric railway vehicle. Effects of the contact loss in the power conversion unit were analyzed via main transformer of railway vehicle, the input and output voltage characteristics of the converter through contact loss was generated after linking the vehicle with feeding system.

• 한국지진공학회논문집
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• 제8권3호
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• pp.43-52
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• 2004

본 연구는 캘리포니아 내 고속도로망을 대상으로 지진발생 후 교통흐름의 변화를 평가하는 기법에 대하여 이루어졌으며, 고속도로망 상에 위치한 교량의 손상정도가 평가기법의 가장 기본적인 요소로 사용되었다. 본 연구에 사용된 교량의 지진취약도는 PGA 또는 PGV의 함수로 나타내어졌고, 1994년 Northridge 지진과 일련의 시나리오 지진에 대하여 교통망 손상 평가를 수행하였다. 또한 교량 보수 및 보강 후 교통망에 대한 피해정도를 정량화하기 위해 확률모델을 개발하였으며, 그 피해정도는 시간(Drivers Delay)으로 나타내었다. 본 연구가 캘리포니아를 대상으로 이루어져 국내적용 및 활용가능성에 대해서는 후속 연구가 뒤따라야 할 것으로 사료된다.

• 수산해양교육연구
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• 제22권1호
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• pp.79-90
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• 2010

This study referred to relevant literatures, collected professional advice, created the sphere of duty with considering the characteristics of marine products-marine transportation education and teachers' specialty, and researched the feasibility of duty sphere classified from 2nd of September in 2008 to 20th of October in 2008 by selecting 80 professional teachers at random teachers who were working in 4 schools that had local 1. As the result of this study, it is proper to classify the sphere of marine products-marine transportation professional teachers into teaching-learning sphere, actual training guidance sphere, life guidance sphere, class management sphere, administrative performance sphere, specialty extension sphere, academic-industrial cooperation and community connection sphere. 2. For the contents of each sphere of marine products-marine transportation teachers' duty, it is proper to systematize teaching-learning field with 32 contents of duty, actual training guidance field with 21 contents of duty, life guidance sphere with 18 contents of duty, class management sphere with 12 contents of duty, administrative performance sphere with 18 contents of duty, specialty extension sphere with 15 contents of duty, academic-industrial cooperation and community connection sphere with 9 contents of duty respectively.

• Steel and Composite Structures
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• 제32권6호
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• pp.717-729
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• 2019

A horizontal cyclic test was carried out to study the seismic performance of lightweight aggregate concrete filled steel tube (LACFST). The constitutive and hysteretic model of core lightweight aggregate concrete (LAC) was proposed for finite element simulation. The stress and strain changes of the steel tube and concrete filled inside were measured in the experiment, and the failure mode, hysteresis curve, skeleton curve, and strain curve of the test specimens were obtained. The influence of axial compression ratio, diameter-thickness ratio and material strength were analysed based on finite element model. The results show that the hysteresis curve of LACFST indicated favourable ductility, energy dissipation, and seismic performance. The LACFST failed when the concrete in the bottom first crushed and the steel tube then bulged, thus axial force imposed by prestressing was proved to be feasible. The proposed constitutive model and hysteretic model of LAC under the constraint of its steel tube was reliable. The bearing capacity and ductility of the specimen increase significantly with increasing thickness of the steel tube. The bearing capacity of the member improves while the ductility and energy dissipation performance slightly decreased with the increasing strength of the steel and concrete.