• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.836-839
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• 2006

This paper presented comparison of vibration characteristics of a 5-ton truck at the two kinds of rear axle suspension, a conventional leaf spring suspension and an air spring suspension. Vibration at the selected location in the freight compartment and the rear axle were measured while the vehicle was running on various kinds of road at the specified speed. At all kinds of the driving conditions used in the test the air spring suspension showed good performance of vibration attenuation, especailly at the frequency range of under 5 Hz.

• 대한안전경영과학회지
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• 제25권3호
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• pp.37-43
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• 2023

Since 2024, small business are also going to be ruled under the Serious Accident Punishment Act. As the scope of the law expands, the small logistics companies are required to pay more attention on preventing serious accidents on the field. Freight vehicle accidents can cause personnel accidents and cargo accidents which are the two serious accidents that the Serious Accident Punishment Act is trying to prevent. The purpose of this research are to study the factors that cause the serious accidents that happens in the small logistics companies and to suggest preventive. The results of the study shows that fall prevention is the top-priority and then driving experience, safety management, and cargo driving hours. However, the gaps between the evaluation values of each are not huge, which means all the preventives are significant.

• 대한교통학회지
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• 제22권5호
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• pp.89-97
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• 2004

현재 군 수송기는 매주 일정 대수가 각 기지 간 물자수송, 인원수송 그리고 조종사들의 훈련목적으로 정해진 스케줄에 의해 운항하고 있다. 일일 수송기 운행 경로는 모 기지에서 이륙하여 몇 개의 기지를 경유하여 임무를 수행한 후, 다시 모 기지로 돌아오는 패턴을 취하고 있다. 본 연구는 공군의 중앙물자를 저장하는 창에서 각 기지로 물자를 수송할 때 물량예측 및 적정노선에 대해서 시계열분석과 차량경로모형이라는 두 가지 방법을 통해 접근한다. 먼저 현재 공군에서 사용하고 있는 각종 규정과 교범상의 항공수송에 대한 제약사항 자료를 수집하여, 이를 바탕으로 본 연구에서는 다회방문이 가능하고, 경우회수에 대한 제약을 갖는 모형시과 알고리즘을 제안하였다. 또한 지난 몇 년간의 수송물량을 시계열 분석을 이용하여 예측하고, 예측된 수송소요를 제안된 알고리즘에 적용하여 적정노선을 계획하는 방법을 제안하였다. 제안된 모형과 알고리즘의 적합성과 경제성을 파악하기 위해 본 연구에서는 모형에서 계산된 수송물량과 필요 수송기 대수와 실제 공군에서 수행된 항공화물 수송 물량과 투입 수송기 대수를 비교함으로써 객관적인 모형의 우수성을 입증하고자 하였다.

• 한국ITS학회 논문지
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• 제22권3호
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• pp.116-130
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• 2023

고속도로는 중장거리 지역 간을 연결하는 자동차 전용도로로 철도 및 항공 수단보다 접근성과 이동성이 우수하여 화물 수송의 중추적인 역할을 담당하고 있다. 그러나 기존의 고속도로를 이용하는 화물수송실적은 차종 구분의 혼재, 개별 화물차량의 화물적재량 파악의 어려움으로 정확한 산정에 한계가 있다. 따라서 본 연구에서는 고속도로 온라인 데이터의 분석을 통하여 보다 신뢰성있는 화물수송실적 산정 방법론의 틀을 제시하고자 하였다. 자동요금징수시스템로부터 수집된 데이터를 활용하여 고속도로 구간별 통행실적(대·km/일)을 도출하였으며 차량제원정보데이터와 고속 및 저속축중기 데이터로부터 차종별 화물 적재 원단위(톤/대)를 도출하였다. 본 연구는 기존에 제시되고 있지 않은 고속도로 구간별, 차종별 화물수송실적을 산정하는데 주요 목적이 있으며, 개방식 영업소, 민자고속도로 등을 모두 연계한 수송실적산정방법을 제시하였다는데 기존 연구와의 차별성을 가진다.

• 산업공학
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• 제16권4호
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• pp.473-484
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• 2003

In this paper we deal with the logistics brokerage process in which a logistics agent intermediates between vehicle owners and shippers for matching empty vehicles and freights. Based on the Multi-Criteria Decision Making (MCDM) methodology, the proposed agent system matches the most preferred empty vehicle to the shipper and the most preferred freight to the vehicle owner. In the proposed agent system, an MCDM based sensitivity analysis is also used for supporting decision makers under negotiations. Among various MCDM methodologies, Analytic Hierarchy Process (AHP) is utilized in this paper. Although AHP is one of the most popular MCDM methodologies, AHP needs a number of pair-wise comparisons for assessing alternatives and hence may give excessive decision making burden to the decision makers. In this paper, in order to reduce the decision making burden, a preference function based estimation method is proposed. We can expect that the MCDM based logistics brokerage agent can be used as an efficient and effective tool for e-logistics marketplaces on the internet.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.280-285
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• 2003

The process of railway traffic planning is composed of several steps such as long-term, mid-term. short-term, and real-time plan. The planning of vehicle and manpower resources is a main research topic in tactical short-term planning step. Railway vehicle is usually consisted of a power car, passenger/freight cars and human resource is composed of engine driver, cabin crew, ground personnel. So far, power car was main research target in railway vehicle scheduling problem. Recently according as the light electric railway or high-speed railway is introduced, the operational planning of trainset vehicles become important, In this paper, we introduce the conceptional model for trainset restoring problem and developed heuristic algorithm.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2003년도 춘계학술대회
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• pp.53-61
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• 2003

The process of railway traffic planning is composed of several steps such as long - term, mid - term, short - term, and real - time plan. The planning of vehicle and manpower resources is a main research topic in tactical short - term planning step Railway vehicle is usually consisted of a power car, passenger/freight cars and human resource is composed of engine driver, cabin crew, ground personnel. So far , power car was main research target in railway vehicle scheduling problem. Recently according as the light electric railway or high - speed railway is introduced, the operational planning of train set vehicles become important . In this paper , we introduce the conceptional model for trainset restoring problem and developed heuristic algorithm.

• 한국도로학회논문집
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• 제18권5호
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• pp.95-103
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• 2016

PURPOSES : Permitted left turn is a turning maneuver in which a vehicle turns left using a gap between oncoming vehicles, called gap acceptance, and it enables for more efficient traffic operation at intersections. In Korea, the permitted left turn has not been a common maneuver at signalized or un-signalized intersections. However, many experts and the Police Agency tried to apply this effective turning maneuver at intersections in Korea since 2010. Though the investigation of gap acceptance is significantly important in understanding a driver's behavior at intersections, there have not been many studies about this topic, specifically a study to develop probability models of gap acceptance behavior. METHODS : In this study, the probability model of gap acceptance behavior for a permitted left turn was developed based on observational field studies. To develop the model, seven variables were analyzed including gap, waiting time, traffic volume, conflict-flow vehicle type, left-turning vehicle type, the number of lane, and time. RESULTS : In the final model, gap and left-turning vehicle type were found to be significant influencing factors. CONCLUSIONS : Through this model development, it was concluded that as the gap size increased, the probability of gap acceptance was higher. Moreover, when a left-turning vehicle was a passenger car, the probability of gap acceptance was higher than compared to large size buses or freight cars.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.133-138
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• 2004

Domestic freight car holding amount is possessing much amount than other vehicle model about 14,000. Problem is happening in bogie device of cast steel structure because is structure that there are many wear departments. Therefore, the KNR is restricting running speed of empty car by 70km/h low. In this research, presented speed elevation way as dynamic characteristic analysis result that use ADAMS and confirm running safety by main line test.

• 대한산업공학회지
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• 제37권4호
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• pp.331-341
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• 2011

This paper considers an inbound lot-sizing and outbound dispatching problem for a single product in a thirdparty logistics (3PL) distribution center. Demands are dynamic and finite over the discrete time horizon, and moreover, each demand has a delivery time window which is the time interval with the dates between the earliest and the latest delivery dates All the product amounts must be delivered to the customer in the time window. Ordered products are shipped by multiple vehicle types and the freight cost is proportional to the vehicle-types and the number of vehicles used. First, we formulate a mixed integer programming model. Since it is difficult to solve the model as the size of real problem being very large, we design a conventional genetic algorithm with a local search heuristic (HGA) and an improved genetic algorithm called adaptive genetic algorithm (AGA). AGA spontaneously adjusts crossover and mutation rate depending upon the status of current population. Finally, we conduct some computational experiments to evaluate the performance of AGA with HGA.