• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.167-177
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• 2012

In this paper, we raised the performance of heuristic algorithm to assign job to workers in parallel line inspection process without sequence. In previous research, we developed the heuristic algorithm. But the heuristic algorithm can't find optimal solution perfectly. In order to solve this problem, we proposed new method to make initial solution called FN(First Next) method and combined the new FN method and old FE method using previous heuristic algorithm. Experiments of assigning job are performed to evaluate performance of this FE+FN heuristic algorithm. The result shows that the FE+FN heuristic algorithm can find the optimal solution to assign job to workers evenly in many type of cases. Especially, in case there are optimal solutions, this heuristic algorithm can find the optimal solution perfectly.

• Journal of Korean Institute of Industrial Engineers
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• v.14 no.2
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• pp.41-51
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• 1988

In this paper an efficient heuristic for the generalized assignment problem(GAP) is presented. A new lower bound that is slightly improved by adding the feasibility constraint is used to measure the quality of solutions obtained by the heuristic. The heuristic was tested on a number of large-scale random problems and a large sample of small problems. The heuristic appears to be better than the best previously existing heuristic for GAP. Its effectiveness in comparison of running times and closenesses to lower bound is discussed.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2477-2484
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• 1997

Best-first heuristic search algorithm, such as $A^{\ast}$ algorithm, are one of the most important techniques used to solve many problems in artificial intelligence. A common feature of heuristic search is its high computational complexity, which prevents the search from being applied to problems is practical domains such as route-finding in road map with significantly many nodes. In this paper, several heuristic search algorithms are concerned. A new dynamic weighting heuristic method called the pat-sensitive heuristic is proposed. It is based on a dynamic weighting heuristic, which is used to improve search effort in practical domain such as admissible heuristic is not available or heuristic accuracy is poor. It's distinctive feature compared with other dynamic weighting heuristic algorithms is path-sensitive, which means that ${\omega}$(weight) is adjusted dynamically during search process in state-space search domain. For finding an optimal path, randomly scattered road-map is used as an application area.

• Korean Management Science Review
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• v.12 no.2
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• pp.77-87
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• 1995

In this paper we develop an efficient heuristic algorithm for the problem of scheduling n sequence-dependent jobs on a basic processor to minimize makespan. Efficient solution methods are already known for the sequence- independent case. But for the sequence-dependent case, this problem belongs to a set of strong NP-complete problems. We present a heuristic which is similar to shortest setup time heuristic but opportunity cost of setup time rather than shortest setup time is used for choosing next job. This heuristic algorithm has same computational complexity and worst case ratio as the shortest setup time heuristic. We used Wilcoxon signed rank test to show that our heuristic is superior to nearest setup time heuristic in term of average behavior.

• Journal of the Korea Safety Management & Science
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• v.10 no.3
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• pp.253-265
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• 2008

In this paper, we developed a heuristic algorithm to assign job to workers in parallel line inspection process without sequence. Objective of assigning job in inspection process is only to assign job to workers evenly. But this objective needs much time and effort since there are many cases in assigning job and cases increase geometrically if the number of job and worker increases. In order to solve this problem, we proposed heuristic algorithm to assign job to workers evenly. Experiments of assigning job are performed to evaluate performance of this heuristic algorithm. The result shows that heuristic algorithm can find the optimal solution to assign job to workers evenly in many type of cases. Especially, in case there are more than two optimal solutions, this heuristic algorithm can find the optimal solution with 98% accuracy.

• Journal of Intelligence and Information Systems
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• v.1 no.1
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• pp.61-72
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• 1995

Dynamic and explicit ordering of strategies is a key process in modeling knowledge-level problem-solving behavior. This paper addressed the important problem of howl to make the scheduler more knowledge-intensive in a way that facilitates the acquisition, integration, and maintenance of the scheduler control knowledge. The solution a, pp.oach described in this paper involved formulating the scheduler task as a heuristic classification problem, and then implementing it as a classification expert system. By doing this, the wide spectrum of known methods of acquiring, refining, and maintaining the knowledge of a classification expert system are a, pp.icable to the scheduler control knowledge. One important innovation of this research is that of recursive heuristic classification : this paper demonstrates that it is possible to formulate and solve a key subcomponent of heuristic classification as heuristic classification problem. Another key innovation is the creation of a method of dynamic heuristic classification : the classification alternatives that are selected among are dynamically generated in real-time and then evidence is gathered for and aginst these alternatives. In contrast, the normal model of heuristic classification is that of structured selection between a set of preenumerated fixed alternatives.

• Journal of Korea Spatial Information System Society
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• v.10 no.2
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• pp.35-48
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• 2008

In this paper, we propose a Dynamic Heuristic to reduce the number of node accesses and improve quality of path in the client-based navigation service. The Dynamic Heuristic is to use heuristic data from server that is calculated with traffic data. The server-based navigation service provides a path searched on server and transmits it to client, but we propose that server only provide heuristic data to client. The proposed client searches a path with heuristic transmitted data from server. We present a new algorithm for using Dynamic Heuristic in the path-finding. The algorithm bases Grid Based Path-Finding, and has minimum speed data of edges in grid. It removes several grids whose minimum speed is less than limited speed.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.86-98
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• 2007

This paper presents a heuristic algorithm for the traveling salesman problem with time windows (TSPTW). Aniterative insertion algorithm as a constructive search heuristic and a hybrid meta heuristic combining simulatedannealing and tabu search with the randomized selection of 2-interchange and a simple move operator as animproving search heuristic are proposed, Computational tests performed on 400 benchmark problem instancesshow that the proposed algorithm generates optimal or near-optimal solutions in most cases. New best knownheuristic values for many benchmark problem sets were obtained using the proposed approach.

• IE interfaces
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• v.21 no.1
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• pp.8-17
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• 2008

A new search procedure, VLT(Vertex Line Tracing) heuristic, for two dimensional irregular shapes nesting problem was suggested in this study. The VLT heuristic was suggested to the nesting problem to overcome disadvantages of the existing NFP(No-Fit-Polygon) method. This VLT heuristic was compared with the results of the existing benchmark problems suggested by Albano, Hopper, and Burke. The results of the VLT heuristic give efficient solutions in the point of the scrap ratio and computation time. A computer program, NestLogic, using C++ for VLT heuristic was also developed for this nesting problem.

• International Journal of Ocean System Engineering
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• v.3 no.1
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• pp.22-32
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• 2013

A heuristic physical theory of diffraction (PTD) for an acoustic impedance wedge is proposed. This method is based on Ufimtsev's three-dimensional PTD, which is derived for an acoustic soft or hard wedge. We modify the original PTD according to the process of physical optics (or the Kirchhoff approximation) to obtain a 3D heuristic diffraction model for an impedance wedge. In principle, our result is equivalent to Luebbers' model presented in electromagnetism. Moreover, our approach provides a useful insight into the theoretical basis of the existing heuristic diffraction methods. The derived heuristic PTD is applied to an arbitrary impedance polygon, and a simple PTD formula is derived as a supplement to the physical optics formula.