• Industrial Engineering and Management Systems
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• 제13권3호
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• pp.319-329
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• 2014

Supply chain management is a subject that has an increasing importance due to the developments in the global markets and technology. In this paper, a fuzzy multi-objective linear programming model is developed for the supply chain of a company dealing with procurement, storage, filling, and distribution of liquefied petroleum gas (LPG) in Turkey. The model intends to determine the quantities of LPG to be procured, stored, filled to cylinders, and transported between the plants and demand centers for six planning periods. In this model, which aims to minimize both total costs (sum of procurement, storage, filling, and transportation costs) and total transportation distances, demand quantities of the main demand centers and decision maker's aspiration levels about objective functions are fuzzy. After comparing the results obtained from the model with those obtained by using different methods, it is concluded that the proposed method can be applied to real world problems practically and it may be used in this type of problems in order to generate an efficient solution.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1993년도 춘계공동학술대회 발표논문 및 초록집; 계명대학교, 대구; 30 Apr.-1 May 1993
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• pp.36-45
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• 1993

This paper presents a model and a heuristic procedure to design production planning and transportation scheduling systems of critical items, components and products on the basis of material requirement planning concept and transportation planning model. These systems are stemmed from a multi-site multi-product production company in a international economic zone. An example is provided to validate the heuristic procedure developed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.317-319
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• 2019

In this paper, a three level duty cycle controlled half bridge LLC converter for EV charger application is presented. The topology and operating regions of the converter are discussed. The equations of the converter are derived in time domain. A small signal model of the converter is developed by perturbation and linearization of the steady state model about their operating point using Extended Describing function.

• 한국항만학회지
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• 제12권1호
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• pp.47-53
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• 1998

Presently, it was faced with serious social problems as traffic accident, parking violation & traffic congestion due to change of industrial structure, expansion of economic volume, elevation of national life level and rapid motorization. Accordingly, the study is research to improve immidiate transportation problems which could be establish the rating model about consideration degree of evaluation factor based on MDPREF's method in connection with Intelligent Transportation System(ITS)

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.922-925
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• 2008

Many highway projects are under way in Korea. However, owners frequently find that the project cost exceeds the budget and they are unable to identify the underlining reasons. The main purpose of this research is to develop cost models for transportation projects in Korea using the multiple linear regression (MLR). The data consist of 27 completed transportation projects, built from 1991 to 2001, The technique of multiple regression analysis is used to develop the parametric cost estimating model for total budget cost per highway square meter (TBC/$m^2$). Findings of the study indicated that MLR car be applied to highway projects in Korea. There are twf) major contributions of this research. (1) the identification of transportation parameters as a significant cost driver for transportation costs and (2) the successful development of the parametric cost estimating models for transportation projects in Korea.

• 산업공학
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• 제20권4호
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• pp.525-538
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• 2007

The importance of efficient container transportation becomes more significant each year due to the constant growth of the global marketplace, and studies focusing on shipping efficiency are becoming increasingly important. In this paper, we propose an approach for vehicle scheduling that decreases the number of vehicles required for freight commerce by analyzing and scheduling optimal routes. Container transportation can be classified into round and single-trip transportation, and each vehicle can be linked in a specific order based on the vehicle state after completing an order. We develop a mathematical model to determine the required number of vehicles with optimal routing, and a heuristic algorithm to perform vehicle scheduling for many orders in a significantly shorter duration. Finally, we tested some numerical examples and compared the developed model and the heuristic algorithm. We also developed a decision support system that can schedule vehicles based on the heuristic algorithm.

• Steel and Composite Structures
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• 제45권1호
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• pp.133-145
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• 2022

Steel fiber composite bar (SFCB) is a novel type of reinforcement, which has good ductility and durability performance. Due to the unique pseudo strain hardening tensile behavior of SFCB, different flexural behavior is expected of SFCB reinforced concrete (SFCB-RC) beams from traditional steel bar reinforced concrete (S-RC) beams and FRP bar reinforced concrete (F-RC) beams. To investigate the flexural behavior of SFCB-RC beam, four points bending tests were carried out and different flexural behaviors between S/F/SFCB-RC beams were discussed. An flexural analytical model of SFCB-RC beams is proposed and proved by the current and existing experimental results. Based on the proposed model, the influence of the fiber volume ratio R of the SFCB on the flexural behavior of SFCB-RC beams is discussed. The results show that the proposed model is effective for all S/F/SFCB-RC flexural members. Fiber volume ratio R is a key parameter affecting the flexural behavior of SFCB-RC. By controlling the fiber volume ratio of SFCB reinforcements, the flexural behavior of the SFCB-RC flexural members such as bearing capacity, bending stiffness, ductility and repairability of SFCB-RC structures can be designed.

• 전자공학회논문지
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• 제53권11호
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• pp.166-174
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• 2016

본 논문에서는 스포츠 이벤트에서 선수단 수송 계획을 위한 혼합 정수 선형 계획법 모델을 제안하였다. 선수단 수송 계획은 선수단을 다수의 숙소에서 경기장까지 최소의 비용과 빠른 시간 계획을 찾는 것이다. 운행 회수를 의사결정 변수로 하고, 전체 수송비용은 최소가 되어야 하는 목적함수가 된다. 제안한 방법은 혼합 정수 선형 계획법을 이용하여 전역 최적점을 찾을 수 있는 장점이 있다. 제안한 방식의 유용성을 확인하기 위해서 시뮬레이션을 수행하고 스포츠 이벤트 관리 서비스 플랫폼(SEMSP)에서 수송 계획을 구축하였다.

• 대한교통학회지
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• 제35권6호
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• pp.481-498
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• 2017

교통시설 투자사업에 대한 타당성조사 시 가장 큰 비율을 차지하는 편익항목은 통행시간 절감편익이며, 이는 통행시간가치를 이용하여 산정한다. 현재 예비타당성조사 표준 지침(5판)에서는 1999년 전국 지역 간 통행 조사 자료를 기반으로 산정된 업무통행 대비 비업무통행 통행시간가치의 비율을 이용하여 비업무통행 통행에 대한 시간가치를 산정하였으며, 여기에 수도권 통행목적 비율과 재차인원을 적용하여 수도권에 대한 통행시간가치를 산정하였다. 수도권 통행은 전국 지역 간 통행과 다른 통행특성을 가지고 있다. 수도권 통행의 경우 복합 대중교통 수단을 이용한 환승이 빈번하게 발생하고 있으며, 통근통행에 장시간을 소요하고 있다. 따라서 본 연구에서는 타당성조사 관련 지침의 통행시간가치 산정방법을 개선함으로써 수도권의 통행 특성을 반영한 통행시간가치를 산정하였다. 수도권 통행 특성 반영을 위하여 기존 비업무통행에 포함된 통근통행을 분리하여 통근통행에 대한 통행시간 가치를 별도로 산정하였다. 통근통행 모형과 비업무 통행 모형에 대한 우도비 검정통계량 검정 결과 두 모형은 통계적으로 유의미한 차이가 있는 것으로 분석되었다. 또한 수도권 통합요금제 시행에 따른 통행 여건을 반영하기 위하여 대중교통 통합 모형을 구축하였다. 대중교통 통합모형의 버스와 지하철의 계수 비교결과 두 수단간 계수는 통계적으로 유의미한 차이가 없는 것으로 분석되었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 춘계학술논문요약집
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• pp.45-46
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• 2018