• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.9A
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• pp.844-851
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• 2010

Recently, AODV routing protocol which one of the table driven method for the purpose data transmission between nodes has been broadly used in mobile wireless sensor networks. An existing AODV has a little overhead of routing packets because of keeping the routing table for activity route and re-routes to recovery the routes in route discontinuation. However that has faults in that excesses useless of the network bandwidth to recovery the route and takes a lone time to recovery the route. This paper proposes an efficient route recovery method for AODV based on wireless sensor networks in connection breaks. The proposed method. The propose method controls the number of RREQ message considering the energy's node and distance between nodes to restrict the flooding range of RREQ message while expanding the range of local repair. In test results, the proposed method are compared to existing method, the number of drops decrease 15.43% and the delay time for re-route decrease 0.20sec.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.5
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• pp.303-313
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• 2019

After a disaster happens in urban areas, many people need support for a quick evacuation. This work aims to develop a method for the calculation of the most feasible evacuation route inside buildings. In the methodology we simplify the geometry of the structural and non structural elements from the BIM (Building Information Modeling) to store them in a spatial database which follows standards to support vector data. Then, we apply the multicriteria analysis with the allocation of prioritization values and weight factors validated through the AHP (Analytic Hierarchy Process), in order to obtain the Importance Index S(n) of the elements. The criteria consider security conditions and distribution of the building's facilities. The S(n) is included as additional heuristic data for the calculation of the evacuation route through an algorithm developed as a variant of the $A^*$ pathfinding, The experimental results in the simulation of evacuation scenarios for vulnerable people in healthy physical conditions and for the elderly group, shown that the conditions about the wide of routes, restricted areas, vulnerable elements, floor roughness and location of facilities in the building applied in the multicriteria analysis has a high influence on the processing of the developed variant of $A^*$ algorithm. The criteria modify the evacuation route, because they considers as the most feasible route, the safest instead of the shortest, for the simulation of evacuation scenarios for people in healthy physical conditions. Likewise, they consider the route with the location of facilities for the movement of the elderly like the most feasible in the simulation of evacuation route for the transit of the elderly group. These results are important for the assessment of the decision makers to select between the shortest or safest route like the feasible for search and rescue activities.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.27 no.1
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• pp.117-123
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• 2023

There are casualties due to inundation and flooding due to intensive typhoons or heavy rains in summer. Due to such damage, the biggest disaster is flood, and in order to reduce human damage, this paper proposes a shortest distance algorithm-based pedestrian path search study using Map API. This system selects Map API through comparative analysis and provides the shortest route. The route explored is in JSON format and the data of the shelter is stored in the database. The route search system designed and implemented based on this data locates pedestrians and provides evacuation routes in case of flash floods. In addition, if the route cannot be entered while moving to the evacuation route, the current location of the pedestrian is identified, the route is re-searched, and a new route is provided. Therefore, it is believed that the pedestrian route search system proposed in this paper will prevent negligent accidents.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.3
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• pp.22-31
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• 2009

In this study, we surveyed the operating status of the Light Sport Aircraft(LSA) in Korea, and reviewed the flight route design for Light Sport Aircraft in Korea.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.143-143
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• 2017

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.11-11
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• 2017

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.65-68
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• 2008

The Mobile IP provides the mobility of Mobile Node, but does not provide the mobility of network. For support the mobility of network, the IETF has proposed NEMO(Network Mobility). Route Optimization is a serious problem in mobile network, so several solutions for route optimization in nested mobile network have been suggested by the IETF NEMO WG. This paper proposes scheme about Route Optimization in nested mobile network.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.139-144
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• 2004

This study aims to analyze the accuracy of rover speed change in route surveying using RTK-GPS. Route surveying methods using GPS contain Static, DGPS, and RTK-GPS. Much research of navigation system, positioning of vehicles by DGPS, and accuracy analysis by GPS surveying have already been done. From this study, it is firstly found that DGPS is suitable for car navigation and sea navigation with an error of meter scale but not good for detailed construction, designing maps and updating GIS databases. Secondly, RTK-GPS can be used for managing gas pipes, water supply and drain pipes and fiber-optic cable that are needed to be controlled in a real time basis. Thirdly, since the accuracies of route surveying by RTK-GPS and DGPS are not correctly matched with the change of rover speed, the choice of route surveying method from those two should follow the need of accuracy fidelity Further study should focus on Cycle Slip problem and coordinate change problem in tunnel and mountainous areas.

• Korean Journal of Computational Design and Engineering
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• v.17 no.2
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• pp.71-78
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• 2012

Recently, the ratio of fuel cost to the operational cost of a ship is increasing according to the increase of the international oil price. Thus, many studies are being made to reduce the cost; for example, a method for acquiring the sea state information, a method for estimating fuel consumption, a method for determining the ship's optimal route, and so on. However, these studies were not incorporated together and being independently made in different fields. In this study, by improving and incorporating such studies, a method for determining a ship economic route based on the acquisition of the sea state and estimation of fuel consumption was proposed. To evaluate the applicability of the proposed method, it was applied to an optimal routing problem of the ocean area including many islands. The result shows that the proposed method can yield the economic route minimizing fuel consumption.

• The Journal of Information Systems
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• v.9 no.1
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• pp.235-255
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• 2000

Facing in very rapidly changing environments via information technologies, we need to study and develop new information technologies in postal delivery service in korea. We study to find the near optimal route for the better postal service between the collection centers. Optimal routing decision for the postal delivery is NP-Hard. The main purpose of this paper is to develop the near optimal simulation technique for the postal routing decision We consider the distance between collection centers, and the quantity of post articles in the collection center to obtain the near optimal route. We use the heuristic algorithm to obtain the near optimal solution for the transportation route of postal articles. Also, we try to show the transportation route by using the map after deciding the near optimal route.