• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2001.10a
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• pp.89-99
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• 2001

Optimum Ship Routing can be defined as “The selection of an optimum track for a transoceanic crossing by the application of long-range predictions of wind, waves and currents to the knowledge of how the routed vessel reacts to these variables”. This paper treats the methodology how to serve optimum ship routing problem by network modeling and reveals the validity of the network model by some numerical experiments.

• Journal of the Korean Institute of Navigation
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• v.25 no.3
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• pp.211-223
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• 2001

Optimum Ship Routing can be defined as \"The selection of an optimum track for a transoceanic crossing by the application of long-range predictions of wind, waves and currents to the knowledge of how the routed vessel reacts to these variables\". This paper treats the methodology how to solve optimum ship routing problem by network modeling and reveals the validity of the network model by some numerical experiments.periments.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2008.10b
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• pp.449-454
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• 2008

Finding an energy efficient route is one of the very important issues in the wireless sensor networks. The route scheme should consider both of the energy level of sensor nodes and the number of hops at the same time. First of all, this paper proposes an optimum routes finding scheme (ORFS), which could be used in the sensor network routing protocols. The scheme uses an optimum value for the path with the considerations of both the minimum energy level of a path and the number of hops at the same time. After that, this paper proposes a routing protocol based on the ORFS for how it could be used for the multipath directed diffusion with data aggregation (MDD-A), to get the better energy efficiency. The analysis result shows that the proposed routing protocol could lengthen the network life cycle about 18.7% compared to the previous MDD-A related protocols.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.1 s.139
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• pp.57-63
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• 2005

This paper introduces basic research of optimum routing assessment system as voyage support purpose which can obtain safe and efficient route. In view point of safety, the prediction of ship motion should be evaluated in the condition of rough weather This part includes general seakeeping estimation based on 3 dimensional panel method and parametric roil prediction. For increasing voyage efficiency, ETA(Estimated Time of Arrival) and fuel consumption should be calculated considering speed reduction and power increase due to wave effects based on added resistance calculation and ship performance characteristics. Basically, the weather forecast is assumed to be prepared previously to operate this system. The idea of these factors in this system will be helpful to escape from dangerous voyage situation by wave conditions and to make optimum route planning based on ETA and fuel consumption.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.2
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• pp.169-176
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• 2000

This paper is considered with the problem of embedding complete binary trees into 3-dimensional meshes using dimension-ordered routing with primary concern of minimizing link congestion. The authors showed that a complete binary tree with $2^P-1$ nodes can be embedded into a 3-dimensional mesh with optimum size, $2^P$ nodes, if the link congestion is two[14], (More precisely, the link congestion of each dimension is two, two, and one if the dimension-ordered routing is used, and two, one, and one if the dimension-ordered routing is not imposed.) In this paper, we present a scheme to find an embedding of a complete binary tree into a 3-dimensional mesh of size no larger than 1.27 times the optimum with link congestion one while using dimension-ordered routing.

• Korean Journal of Computational Design and Engineering
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• v.2 no.1
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• pp.1-10
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• 1997

Finding the optimum route of ship's pipes is complicated and time-consuming process. Experience of designers is the main tool in this process. To reduce design man-hours and human errors a design expert system shell and a geometric modeler is used to automate the design process. In this paper, a framework of the intelligent CAD system for pipe auto-routing is suggested, which consists of general-purpose expert system shell and a geometric modeler. The design expert system and the geometric modeling kernel have been integrated. The CADDS5 of Computervision is used as the overall CAD environment. The Nexpert Object of Neuron Data is used as the expert system shell. The CADDS5 ISSM is used as the interface that creates and modifies geometric models of pipes. Existing algorithms for the routing problem have been analyzed. Most of them are to solve the 2-D circuit routing problems. Ship piping system, specially within the engine room, is a complicated, large scale 3-D routing problem. Methods of expert system have been used to find the route of ship pipes on the main deck.

• Journal of Navigation and Port Research
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• v.40 no.3
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• pp.97-103
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• 2016

The precise prediction of ships propulsion performance is very important to find out the ships optimum route. This paper describes the development of computer program to generate the database of propulsion performance for the ships optimum routing system. The propulsion performance of ship in the sea is caused by not only ships conditions such as drift and hull roughness, but also various sea conditions such as wave and wind. These prediction methods of added resistance are based on the ships speed trial analysis methods of the ISO 15016:2002 standard, and a few prediction methods of the wind and hull roughness are supplemented. These prediction methods have been applied to the comprehensive computer program. And the database calculation for the research ice breaker the Araon has been carried out, which shall be used for the calculation of optimum route. Furthermore, this program shall be used for the route optimization in global shipping routes.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.10
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• pp.49-56
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• 1992

A new global routing algorithm which dynamically adjusts its cost parameters depending on the given routing poroblem to find a near optimum solution has been developed. The proposed algorithm efficiently performs global routing on general area in which all the pin positions are given. This algorithm is composed of two phases`In the first phase, it routes each net by searching a minimum cost path while ignoring the channel capacity. In the second iterative phase, it rips up nets which pass the channel at which the horizontal or vertical routing density exceeds the capacity and then it reroutes them using a modified set of cost parameters. Applying the above phases, paths for nets are found such that routing density doesn't exceed the capacity in each channel and that nets are routed with minimum cost. Experimental results for several benchmark examples including difficult-4, difficult-8, difficult-16, Primary1 and Primary2 show that our method generates better results than other published ones.

• Journal of Advanced Navigation Technology
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• v.11 no.3
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• pp.296-305
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• 2007

The HiLow, a hierarchical routing protocol for 6LoWPAN, needs smaller memory allocation and energy than other routing protocols. However, the HiLow has a weak point that does not provide the optimized routing path. In this paper, we propose the algorithm that can find the optimum next hop using neighboring nodes around the source node as well as hierarchical routing path information. We evaluate the performance of proposed algorithm using the computer simulation, and we can acquire results that decreases a number of hop count and transmitted message.

• Management Science and Financial Engineering
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• v.11 no.2
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• pp.45-60
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• 2005

This paper investigates the application of the computer method COMSOAL (Computer Method of Sequencing Operations for Assembly Lines) to the process routing (PR) problem with multiple objectives. In any computer aided process planning (CAPP) system, one of the most critical activities for manufacturing a part could be to generate the sequence that optimizes production time, production cost, machine utilization or with multiple these criteria. The COMSOAL has been adopted to find the optimum sequence of operations that optimizes two major conflicting criteria : production cost and production quality. The COMSOAL is here slightly modified to simultaneously generate and evaluate a set of possible solutions (called as population) instead of processing a solution stepwise in each iteration. The significant features of the COMSOAL include : no parameters settings needed, and a guarantee of feasible solutions. Experimental results show that COMSOAL is a simple but powerful method to quickly generate multiple feasible solutions which are as good as the ones obtained from several other well-known process routing algorithms.