• Industrial Engineering and Management Systems
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• 제3권2호
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• pp.92-99
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• 2004

We consider the ATM switching node location problem (ANLP). In this problem, there are two kinds of facilities, hub facilities and remote facilities, with different capacities and installation costs. We are given a set of customers with each demand requirements, a set of candidate installation sites of facilities, and connection costs between facilities. We need to determine the locations to place facilities, the number of facilities for each selected location, the set of customers who are connected to each installed hub via installed remote facilities with minimum cost, while satisfying demand requirements of each customer. We formulate this problem as a general integer programming problem and solve it to optimality. In this paper, we present a preprocessing procedure to tighten the formulation and develop a branch-and-price algorithm. In the algorithm, we consider the integer knapsack problem as the column generation problem. Computational experiments show that the algorithm gives optimal solutions in a reasonable time.

• 산업기술연구
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• 제38권1호
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• pp.9-13
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• 2018

FRP(Fiber Reinforced Plastic) ships are easy to manufacture and repair. Also they are more durable and cheaper than steel wires and neck lines. Therefore FRP ships are widely used in small ships. In Korea, the amount of waste FRP ships is increasing. It is expected that a large amount of waste FRP ships will be generated. Waste FRP ships are emerging as a social problem, such as the difficulty in preserving the marine environment. To improve this, a waste FRP ship melting process system has been developed. In order to construct an effective waste FRP ship processing system, it is necessary to study the treatment facilities location problem. In this paper, we suggest mathematical model to solve optimal location problem of waste FRP Ships and discuss on results by applying it to nine regions selected as candidates for treatment facilities.

• 산업공학
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• 제16권spc호
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• pp.21-27
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• 2003

Objective of this paper is to develop the user mobility model(UMM) which is used for the performance analysis of location update and paging algorithm and at the same time, consider the user mobility pattern(UMP) in zone-based cellular networks. User mobility pattern shows correlation in space and time. UMM should consider these correlations of UMP. K-dimensional Markov chain is presented as a UMM considering them where the states of Markov chain are defined as the current location area(LA) and the consecutive LAs visited in the path. Also, a new two dimensional Markov chain composed of current LA and time interval is presented. Simulation results show that the appropriate size of K in the former UMM is two and the latter UMM reflects the characteristic of UMP well and so is a good model for the analytic method to solve the performance of location update and paging algorithm.

• 산업경영시스템학회지
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• 제45권4호
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• pp.217-224
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• 2022

Due to the issue of the sustainability in transportation area, the number of electric vehicles has significantly increased. Most automakers have decided or planned to manufacture the electric vehicles rather than carbon fueled vehicles. However, there are still some problems to figure out for the electric vehicles such as long charging time, driving ranges, supply of charging stations. Since the speed of growing the number of electric vehicles is faster than that of the number of charging stations, there are lack of supplies of charging stations for electric vehicles and imbalances of the location of the charging stations. Thus, the location problem of charging stations is one of important issues for the electric vehicles. Studies have conducted to find the optimal locations for the charging stations. Most studies have formulated the problem with deterministic or hierarchical models. In this paper, we have investigated the fluctuations of locations and the capacity of charging stations. We proposed a mathematical model for the location problem of charging stations with the vehicle routing problem. Numerical examples provide the strategy for the location routing problems of the electric vehicles.

• 반도체디스플레이기술학회지
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• 제22권3호
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• pp.41-45
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• 2023

Currently, the method of loading items in the warehouse, the worker directly decides the loading location, and the most used method is to load the product at the location closest to the entrance. This can be effective when there is no difference in the required amount for goods, but when there is a difference in the required amount for goods, it is inefficient because items with a small required amount are loaded near the entrance and occupy the corresponding space for a long time. Therefore, in order to minimize the release time of goods, it is essential to select an appropriate location when loading goods. In this study, a method for determining the loading location by predicting the required amount of goods was studied to select the optimal loading location. Deep learning based bidirectional long-term memory networks (Bi-LSTM) was used to predict the required amount for goods. This study compares and analyzes the release time of goods in the conventional method of loading close to the entrance and in the loading method using the required amount for goods using the Bi-LSTM model.

• 산업경영시스템학회지
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• 제31권2호
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• pp.19-27
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• 2008

This paper addresses determining the location of the distribution centers in a discrete dynamic distribution system. In discrete and finite time horizon, the demands of retailers are dynamic for the periods. Some locations among the retailers can be chosen for the role of the distribution centers at the beginning of each period. The distribution centers have to be located at the location of minimizing logistics cost. Logistics cost factors are the operation cost and the fixed cost of distribution center, and the transportation cost. The distribution centers of minimizing sum of operation cost, fixed cost and transportation cost are determined among retailers in each period for the planning period. A mathematical model was formulated and a dynamic programming based algorithm was developed. A numerical example was shown to explain our problem.

• 대한산업공학회지
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• 제28권4호
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• pp.425-434
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• 2002

Mobility of service users makes location update and paging (L/P) procedures indispensable features in mobile communication networks. Importance of optimizing the configuration of L/P areas has been increased by the growth of L/P related signaling. In this study, we deal with the L/P configuration which an LA (Location Area) may contain multiple PAs (Paging Areas). Given the network topology, L/P related parameters, and traffics generated by each cell, is provided the problem of finding optimal LA/PA configuration minimizing the amount of L/P related signaling. The optimization problem is solved using a simulated annealing, and detailed computational results are conducted to capture the effects of mobility, call arrival patterns and boundary crossing rate on the LA and PA configurations.

• 산업경영시스템학회지
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• 제21권48호
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• pp.1-14
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• 1998

This paper describes a study which was undertaken in Ulsan City. The modified SLP procedures consider the quantitative flow aspect of the facilities layout problem as well as the qualitative closeness rating aspect. Conclusions are drawn as to the effectiveness of the proposed model in providing Ulsan City with better means of making the facilities location allocation decision for Industrial Technology Research Park.

• 기술혁신학회지
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• 제14권3호
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• pp.599-621
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• 2011

본 연구는 부산 울산 경남의 동남권 지역에 집중되어 위치한 조선 산업에서 산업클러스터의 존재여부를 도출하고 그 위상을 파악하여 앞으로의 정책추진에 있어 주요한 기준을 제시하고자 했다. 이에 본 연구는 입지계수(LQ: location quotient)를 활용한 특화도 분석을 통하여 부산 울산 경남의 동남권지역의 산업클러스터 여부를 실증적으로 확인했다. 이는 산업클러스터의 구체적인 발전전략을 세우기에 앞서 먼저 산업클러스터를 확인하는 작업이 필요하기 때문이다. 분석결과 이 동남권의 입지계수의 값은 1.25보다 작은 결과가 도출되어 이 지역의 조선산업은 아직 특화되지 못했음이 밝혀졌고, 부산 울산 경남지역 각각의 경우도 이러한 과정을 통해 이 지역의 조선 산업이 아직 특화되지 못했음이 분석되었다. 한편 이러한 분석을 통해 앞으로 세 지역 중 어떤 곳과 조선관련 산업 중 어떤 업종이 각각 전국 대비 가장 특화될 가능성이 높은지도 밝혀졌다.

• 산업경영시스템학회지
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• 제23권58호
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• pp.29-39
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• 2000

This paper concerns the location of the transit point between adjacent loops and guide direction of loops in the tandem configuration manufacturing system. The tandem configuration has been used to solve control problems like the vehicle dispatching and traffic control. The transit point between loops needs to deliver the parts from one loop to another. The location of transit point between adjacent loops and direction of loops must be determined to minimize the total travel time of parts in the manufacturing system. The model formulation is developed, a numerical example is shown.