• 산업경영시스템학회지
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• 제44권1호
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• pp.26-36
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• 2021

The topic of this study is the field of humanitarian logistics for disaster response. Many existing studies have revealed that compliance with the golden time in response to a disaster determines the success or failure of relief activities, and logistics costs account for 80% of the disaster response cost. Besides, the agility, responsiveness, and effectiveness of the humanitarian logistics system are emphasized in consideration of the disaster situation's characteristics, such as the urgency of life-saving and rapid environmental changes. In other words, they emphasize the importance of logistics activities in disaster response, which includes the effective and efficient distribution of relief supplies. This study proposes a mathematical model for establishing a transport plan to distribute relief supplies in a disaster situation. To determine vehicles' route and the amount of relief for cities suffering a disaster, it mainly considers the urgency, effectiveness (restoration rate), and uncertainty in the logistics system. The model is initially developed as a mixed-integer nonlinear programming (MINLP) model containing some nonlinear functions and transform into a Mixed-integer linear programming (MILP) model using a logarithmic transformation and piecewise linear approximation method. Furthermore, a minimax problem is suggested to search for breakpoints and slopes to define a piecewise linear function that minimizes the linear approximation error. A numerical experiment is performed to verify the MILP model, and linear approximation error is also analyzed in the experiment.

• 한국분무공학회지
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• 제29권2호
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• pp.68-74
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• 2024

As awareness of environmental pollution problems increases worldwide, interest in air pollutants is increasing. In particular, NOx and PM, which are major pollutants in diesel vehicles, are contributing significantly to emissions. As a result, its importance is increasing. In this study, based on research results applied to large diesel vehicles, the problem of natural regeneration caused by low exhaust gas temperature during low speed and low load operation is solved by applying a complex regeneration DPF that is not affected by temperature conditions to small diesel vehicles. The feasibility of application to small diesel vehicles was reviewed by measuring the emission reduction efficiency. As a result of the engine test, the power reduction rate and fuel consumption rate before and after device installation under full load conditions were 2.9% decrease and 3.5% increase, respectively, satisfying the standard for a 5% reduction, and as a result of the regeneration equilibrium temperature (BPT) test, the regeneration temperature was 310℃. appeared at the level. The reduction efficiency test results for the actual vehicle durability test equipment showed 97.3% PM, 51.0% CO, and 31.1% HC, while the city commuter vehicle had PM 97.5%, CO 61.7%, HC 40.0%, and the school bus vehicle had PM 96.8%, CO 44.4%, HC 34.3%, and low-speed logistics vehicles showed a reduction efficiency of 98.2% for PM, 36.0% for CO, and 45.7% for HC. Based on the results of this study, in the future, it is necessary to secure DPF technology suitable for all vehicle types through actual vehicle application research on temperature condition-insensitive composite regenerative DPF for medium-sized vehicles.

• 한국항만경제학회지
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• 제21권4호
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• pp.161-181
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• 2005

This paper investigates the circumstances and conditions of Mokpo Port to develop it as an international logistics stronghold and seeks scheme to maximize the local economic ripple effect through construction and activation of Mokpo New Port. Under the circumstances in which neighboring ports vying with each other have built broad spheres of influence, and competition among ports becomes fierce, a priority cargo attraction strategy should be established by using Mokpo's favorable location compared to other ports in order to ensure that a large quantity of goods is transported from Mokpo New Port. Especially, Mokpo New Port needs to be developed as a vehicles-only exporting port, as well as a port for used car exports and an import port for stones and timber.

• 경영과학
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• 제29권2호
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• pp.157-165
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• 2012

This paper researches on the effective and efficient logistics policy for the parcel express company. The paper derives new policy by considering the number of used vehicles, carbon emission amount, delivery completion time, etc. The maximum waiting of delivery is considered as the time limit T day. To verify the effectiveness of the derived policy, the data of 30 days is generated, and it was shown that the derived policy is very effective compared with the conventional one.

• 산업공학
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• 제11권1호
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• pp.119-129
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• 1998

The relative importance of Logistics in steelworks industry is rather higher among other business activities. The objective of the paper is to propose the methodology for real-time vehicle scheduling for scrap disposal in the steelworks industry. Currently, the rule necessary to assign vehicles to a specific job is strictly fixed. The paper adopts the multi-pass rule selector (MPRS) that suggests a promising rule used for vehicle dispatching for a period of time. The MPRS is regularly invoked if necessary and then evaluates a set of rule candidates to select the best rule with respect to the system performance criteria. The experiment shows that the proposed approach outperforms the current single-pass strategy.

• 한국국방경영분석학회지
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• 제22권1호
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• pp.67-80
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• 1996

Artificial Intelligence(AI) techniques and Object-Oriented(OO) techniques contribute to the simulation modeling of the complex systems. AI techniques are suitable to model human reasoning in the simulation. While OO techniques have advantages of re-usability, maintainability and extendability of the software. Thus, in this paper, we design a knowledge-based object-oriented simulation model, particularly for the logistics analysis of military armor vehicles. The simulation model consists of three modules i.e., scenario, simulation mechanism, and inference engine. The model is designed within the OO paradigm and implemented by using the C++ language. An example case of using the model for the logistic analysis is included.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1978-1983
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• 2008

With the increase in population, the area of human activities has expanded, resulting in the dramatic increase in the need for transportation system. Various infrastructures necessary for efficient logistics, however, have not been supplied enough and the logistics efficiency in Korea is in a bad situation now. As a result of the situation, the demand for the railroad transportation system that can provide large volume transportation has increased dramatically. An electric railway system is composed of high-tech subsystems, among which main electric equipment such as motors and converter are critical components determining the performance of electric vehicle. Among the on-board equipments, traction equipment is important part that has influence on safety and performances of vehicles. We is studied for high-speed train of foreign countries. From this research, we knows that axle weight of HEMU-400x is reasonable within 13ton.

• 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.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.289-295
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• 2004

본 연구의 목적은 컨테이너터미널의 하역시스템 장비조합을 분석하는 것이다. 일반적으로 컨테이너터미널의 생산성은 안벽에서 컨테이너크레인의 생산성에 의해 평가되고 있으나 이송차량과 야드크레인과 같은 다른 장비도 있다. 그러므로 컨테이너 터미널에서 하역시스템의 최적장비조합을 추정할 수 있는 방법이 요구된다. 다양한 시뮬레이션 실험을 수행하고 생산성 향상을 위한 장비조합을 분석한다. 사례연구의 적용으로부터 장비조합에 따른 평균대기시간비율을 사용하여 절감효과를 설명하였다.

• 대한교통학회지
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• 제19권5호
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• pp.7-18
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• 2001

본 연구는 도시물류 문제를 미시적 및 거시적 관점으로 정의하고, 국내외 문헌의 현황 및 한계점을 밝히고, 향후 연구방향을 제시하며, 정책 대안을 평가하는 모형을 개념적으로 제시하는 것을 목적으로 하였다. 문헌의 한계점을 바탕으로 하여 추후 연구 방향으로서는 도시내 물류활동 주체인 화주, 제품공급업자 등을 고려하는 미시적 관점의 연구가 강화되어야 한다는 점과 다양한 정책 대안들을 보다 효과적으로 평가할 수 있는 개념적 평가 모형 정립의 필요성 그리고 물류활동 주체와 도시 교통 문제를 함께 평가할 수 있는 통합 모형의 구축을 제의하였다. 도시물류 개선 대안을 평가하기 위한 모형을 개념적으로 제시하는 데 있어서 거시적 관점과 미시적 관점의 상관관계를 정리하고, 미시적 관점에서 관련 주체별 평가 요소를 도출하고 이를 바탕으로 평가 모형을 구체화하였다. 특히, 최근 시도된 시뮬레이션 기법을 이용한 화물차량경로 예측 방법을 제시하고, 모형을 통하여 도시물류 개선을 위한 정책 대안이 각 물류활동의 주체에게 미치는 영향을 미시적 및 거시적 관점에서 평가할 수 있음을 밝혔다. 또한 향후 본 연구에서 제시된 모형들을 보다 구체화하는 노력이 필요할 뿐 아니라 재고관리 시스템을 통한 수요예측 기법 등의 기초 연구가 계속되어야 함을 강조하였다.