• Korean Journal of Computational Design and Engineering
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• v.6 no.3
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• pp.174-183
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• 2001

This study proposes an improved genetic algorithm (GA) to derive solutions for facility layout problems having inner walls and passages. The proposed algorithm models the layout of facilities on a flour-segmented chromosome. Improved solutions are produced by employing genetic operations known as selection, crossover, inversion, mutation, and refinement of these genes for successive generations. All relationships between the facilities and passages are represented as an adjacency graph. The shortest path and distance between two facilities are calculated using Dijkstra's algorithm of graph theory. Comparative testing shows that the proposed algorithm performs better than other existing algorithm for the optimal facility layout design. Finally, the proposed algorithm is applied to ship compartment layout problems with the computational results compared to an actual ship compartment layout.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.2
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• pp.33-39
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• 2015

Power supplying capacity of the distribution feeder should be maintained within thermal capacity of the wire. This paper presents the minimum spanning tree based load balancing technique to release multiple overloading of distribution feeders. In order to minimize number of involved backup feeders, Dijkstra and Prim algorithm are adopted to construct minimum spanning tree. Simulation testing result based on part of KEPCO's commercial distribution systems shows effectiveness of proposed scheme.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.569-575
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• 2007

This paper presents a study on a Dijkstra algorithm for shortest paths to destinations and a modified algorithm of Multicommodity Network Flow Problem Model with a network transformation for evacuation planning from railroad accident in a directed network.

• 한국ITS학회:학술대회논문집
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• 2004.11a
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• pp.343-348
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• 2004

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.5
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• pp.385-391
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• 2013

As a solution for environmental problems caused by increasing number of vehicles, it is encouraged to use a bicycle as an environment-friendly transportation method. To vitalize the bicycle usage, it is a necessary to construct bicycle roads that are safe and suitable for users. Based on the previous research results, we assume the main purposes of bicycle usages are mainly local leisure activity and school commuting. Thus, the proposed method finds the shortest link between the existing bicycle road network and bicycle usage facilities such as leisure activity places or schools over public road network. Then, we carry out the RTK DGPS survey for the candidate links, and analyze the slopes of them. When the slope of a found link is larger than a threshold, an alternative link is re-found for the safety and convenience of a bicycle user. The proposed method is applied to the real bicycle road network in Mokpo, Chunnam and the results are discussed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.5
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• pp.36-45
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• 2013

This paper developed a new shortest path searching algorithm based on Dijkstra's algorithm and $A^*$ algorithm, so it guarantees to find a shortest path in efficient manner. In this developed algorithm, minimum expected weights implies the value that straight line distance from a visiting node to the target node multiplied by minimum link unit, and this value can be the lowest weights between the two nodes. In behalf of the minimum expected weights, at each traversal step, developed algorithm in this paper is able to decide visiting a new node or retreating to the previously visited node, and results are guaranteed. Newly developed algorithm was tested in a real traffic network and found that the searching time of the algorithm was not as fast as other $A^*$ algorithms, however, it perfectly found a minimum path in any case. Therefore, this developed algorithm will be effective for the domain of searching in a large network such as RGV which operates in wide area.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.3
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• pp.3-9
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• 2013

As interest in green growth picks up, the importance of bicycles which are an environment friendly means of communication has been magnified. However, bicycle routes which are the base of bicycles are designed without considering topographic elements and thus many users are experiencing inconvenience in using bicycles. The present study presents a routing technique to select optimal routes when selecting routes in commuting to school utilizing bicycles. To this end, a formula for optimum route calculation considering slope and intersections was drawn and a method to select optimum routes by applying modified Dijkstra Algorithms was studied. According to the results, the bicycle routes for commuting to school should be selected by the shortest time rather than the shortest distances to the destination, because it required reach the destination faster. Therefore when selecting the routes, it must be based on the shortest time considering waiting time due to crosswalks or crossroads and speed variations due to slopes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.494-497
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• 2022

Recently, the damage caused by flash floods caused by extreme weather due to global warming is increasing. In order to reduce the damage, this paper conducted a study on the search for the shortest route of an evacuation route due to a flash flood. For this, we implemented a route search system using GIS and shape files including buildings and roads and Dijkstra's algorithm. In this study, the location of users close to the point where the flash flood occurs is identified, and the evacuation route is searched from the starting point to the destination point without passing through the dangerous point. Evacuate out of the test bed, or designate a building in the test bed as an evacuation shelter, and search for a route to the nearest evacuation shelter. Accordingly, it is expected that human damage will be reduced by providing the shortest evacuation route.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.3
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• pp.12-19
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• 2010

In road network, especially in urban area, inefficiency of travel time is caused by signal control and turn maneuver at intersection and this inefficiency has substantial effects on travel time. When searching for the shortest path, this inefficiency which is caused by turn maneuver must be considered. Therefore, travel time, vehicle volume and delay for each link were calculated by using simulation package, PARAMICS V5.2 for adaptation of turn penalty at 16 intersections of Gangnam-gu. Turn penalty was calculated respectively for each intersection. Within the same intersection, turn penalty differs by each approaching road and turn direction so the delay was calculated for each approaching road and turn direction. Shortest path dealing with 16 intersections searched by Dijkstra algorithm using travel time as cost, considering random turn penalty, and algorithm considering calculated turn penalty was compared and analyzed. The result shows that by considering turn penalty searching the shortest path can decrease the travel time can be decreased. Also, searching the shortest path which considers turn penalty can represent reality appropriately and the shortest path considering turn penalty can be utilized as an alternative.

• Journal of Korean Society of Transportation
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• v.21 no.2
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• pp.71-82
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• 2003

The shortest path problems(SPP) are critical issues in the military logistics such as the simulation of the War-Game. However, the existing SPP has two major drawbacks, one is its accuracy of solution and the other is for only one solution with focused on just link cost in the military transportation planning models. In addition, very few previous studies have been examined for the multi-shortest path problems without considering link capacity reflecting the military characteristics. In order to overcome these drawbacks, it is necessary to apply the multi-shortest paths algorithm reflecting un-expected military incidents. This study examines the multi-shortest paths in the real networks using Shier algorithm. The network contains both military link capacity and time-based cost. Also, the modes are defined as a platoon(group) rather than unit which is used in most of previous studies in the military logistics. To verify the algorithm applied in this study. the comparative analysis was performed with various sizes and routes of network which compares with Dijkstra algorithm. The major findings of this study are as follows ; 1) Regarding the unique characteristics of the military transportation plan, Shier algorithm, which is applied to this study, is more realistic than Dijkstra algorithm. Also, the time based concept is more applicable than the distance based model in the military logistics. 2) Based on the results from the various simulations of this study the capacity-constraint sections appeared in each scenarios. As a consequence, the alternatives are necessary such as measures for vulnerable area, improvement of vehicle(mode), and reflection of separated-marching column in the military manuals. Finally. the limits and future research directions are discussed : 1) It is very hard to compare the results found in this study. which is used in the real network and the previous studies which is used in arbitrary network. 2) In order to reflect the real military situations such as heavy tanks and heavy equipment vehicles. the other constraints such as the safety load of bridges and/or the height of tunnels should be considered for the future studies.