• Journal of Korean Society of Transportation
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• v.19 no.4
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• pp.85-96
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• 2001

This paper discusses the problem of finding the Origin-Destination(O-D) shortest path in urban road networks that have variable special qualifies such as time windows for passing as well as geometrical special qualities such as U-turn and left-turn prohibition. The focus of this paper is motivated by the problem of finding minimum travel time paths for an advanced traveler information system (ATIS) in the context of intelligent transportation system(ITS) application. The transportation network with variable and geometrical special qualities is a more realistic representation of the urban road network in the real word. But, the traditional and existing shortest path algorithms can not search practical shortest path that variable special quality is reflected. This paper presents a shortest path algorithm which can search reasonable shortest path information for the urban ATIS application within a real time. The algorithm is based on genetic algorithm(GA). The high performance of the proposed algorithm is demonstrated by computer simulations.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1571-1572
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• 2015

기존 궤도특수차는 디젤유를 사용하기 때문에 도시철도 지하환경을 오염시키고 유해한 배기가스가 인체에 악영향을 준다. 따라서 경제성이 우수한 친환경적인 하이브리드형 궤도특수차를 개발하기 위해 이에 따른 궤도특수차의 주행동력장치에 대한 설계조건을 규명하고자 한다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.3
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• pp.183-187
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• 2016

Recently, power demand has been increasing every year according to variation of electrical equipments and temperature rise in summer season. So, much more overhead line is being demanded to copy with increasing power demand and operate reliable power system. This paper analysis the characteristics of long span overhead transmission line using special high-tension wire in such as a safety factor, coefficient of elasticity, and the coefficient of linear expansion. Based on the analysis, we proposed the effectiveness of special high-tension wire having much more advantages with respect to height of steel tower and dip compared with conventional ACSR in long span overhead transmission line.

• The Korean Journal of Emergency Medical Services
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• v.26 no.1
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• pp.87-99
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• 2022

Purpose: This study aimed to provide basic data for the improvement of the standards related to the performance improvement of the firefighting equipment standards for special ambulances. Methods: Among the domestic firefighting equipment standards, the special ambulance standard was compared with the NFPA 1917 standard for the United States automobile ambulance 2019 and European Union European standard EN 1789 medical vehicle and its equipment, a road ambulance. Results: Anti-skid performance based on indoor noise standards, performance standards for interior lights, seat belt warning device, child car seat fixing device, safety handle, auxiliary footrest, and flooring materials should be supplemented. Conclusion: It is necessary to strengthen the production and performance standards for improvement to a level corresponding to the national standards, such as the United States and European Union.

• Proceedings of the KOR-KST Conference
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• 1993.02a
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• pp.70-83
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• 1993

• Aerospace Engineering and Technology
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• v.10 no.1
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• pp.20-29
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• 2011

There are a lot of electrical and electronic components and pneumatic parts sensitive to vibration and shock in the VEB assembly which KARI directly transports among the KSLV-I upper stage transportation items. So, the special attention in the transportation is required. The transportation container with the apparatus for controlling environment was made in order to meet the requirements. The transportation tests using the engineering model were performed 4 times to verify the performance of the transportation container and to conform the transportation conditions(transportation velocity, route, etc.). In this document, the previous transportation history of the VEB assembly, the overview and the result of the KSLV-I FM unit 2 VEB assembly transportation are described.

• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.449-460
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• 2007

Several fuzzy approaches can be considered for solving multi-objective transportation problem. This paper presents a fuzzy goal programming approach to determine an optimal compromise solution for the multiobjective transportation problem. We assume that each objective function has a fuzzy goal. Also we assign a special type of nonlinear (hyperbolic) membership function to each objective function to describe each fuzzy goal. The approach focuses on minimizing the negative deviation variables from 1 to obtain a compromise solution of the multiobjective transportation problem. We show that the proposed method and the fuzzy programming method are equivalent. In addition, the proposed approach can be applied to solve other multiobjective mathematical programming problems. A numerical example is given to illustrate the efficiency of the proposed approach.

• Environmental and Resource Economics Review
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• v.9 no.2
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• pp.393-420
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• 2000

Since the transportation taxes were imposed on gasoline and diesel in 1994 for the purpose of financing the special projects, such as the construction of highways or railroads, the rates have been frequently and rapidly changed in case of need to stabilize prices or secure public fund, contrary to its own purpose. This paper presents a theoretical model for a special purpose tax based on the minimization of the dead weight los incurred by the imposition of the tax. A computable static model for the tax rate is developed and estimated for a various range of target level of total tax rebenue. The results shows that, under tax revenue of 40 trillion won, the rates for the year of 1999 are 385.2 won for one liter of gasoline and 198.4 won for one liter of diesel. The estimated gasoline rate is no more than about 59% of the current rate. However, the rate for diesel turns out to be 24% higher than the current level.

• Journal of the Korea Safety Management & Science
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• v.16 no.1
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• pp.29-35
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• 2014

The purpose of this study is to investigate the problem on safety and health training system in Occupational Safety and Health Act(OSHA) and to find countermeasures to improve it in the construction industry. The questionary survey was done on aiming at tracing the legal drawbacks of safety and health training system. The questionary was prepared to target on site workers, management supervisors, and safety supervisors in various construction sites. After analyzing the answers from the survey, realistic and optimal countermeasures on derived problems were proposed. These should be included on the next revision of OSHA.

• ETRI Journal
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• v.44 no.2
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• pp.179-182
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• 2022