• 대한산업공학회지
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• 제27권3호
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• pp.250-259
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• 2001

Given a tree structured network in which each node has its own demand and also stands for a candidate location of a potential facility, such as plant or warehouse, a capacitated facility location problem on the network (CFLPOT) is to decide capacitated facility locations so that the total demand occurred on the network can be satisfied from those facilities with the minimum cost. In this paper, we first introduce a mixed integer programming formulation for CFLPOT with two additional assumptions, the indivisible demand assumption and the contiguity assumption and then show that it can be reformulated as a tree partitioning problem with an exponential number of variables. We then show that it can be solved in O($n^2b$) time by utilizing the limited column generation method developed by Shaw (1993), where n is the total number of nodes in the network and b is the maximum facility capacity. We also develop a depth-first dynamic programming algorithm with a running time of O(nb) for finding the locally maximal reduced cost which plays an important role in the limited column generation method. Finally, we implement our algorithms on a set of randomly generated problems and report the computational results.

• Genomics & Informatics
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• 제1권1호
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• pp.25-31
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• 2003

Local alignment is an important task in molecular biology to see if two sequences contain regions that are similar. The most popular approach to local alignment is the use of dynamic programming due to Smith and Waterman, but the alignment reported by the Smith-Waterman algorithm has some undesirable properties. The recent approach to fix these problems is to use the notion of normalized scores for local alignments by Arslan, Egecioglu and Pevzner. In this paper we consider the problem of finding all local alignments whose normalized scores are above a given threshold, and present a fast heuristic algorithm. Our algorithm is 180-330 times faster than Arslan et al.'s for sequences of length about 120 kbp and about 40-50 times faster for sequences of length about 30 kbp.

• 한국생산제조학회지
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• 제24권3호
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• pp.327-333
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• 2015

As industrial robots come into wider use, their control techniques are being developed along with enhancements in their performance. Specially, the dynamic performance of a 6-axis articulated industrial robot is greatly changed according to the position and orientation of the robot. This means that the PI parameter tuning of the robot and orientation of the robot. This mconsidering the dynamic characteristics of robot mechanism. In this study, $LabView^{(R)}$ programming was applied to automatically conduct parameter scheduling for various robot motions. Using forward and inverse kinematics of RS2, we can divide the working envelope of RS2 into 24 subspaces. We then conduct the gain-tuning according to each subspace. Finally, we program the actual gain scheduling, in which the optimized gain-tuning for each subspace to be passed should be changed for various robot motions using $LabView^{(R)}$.

• 경영과학
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• 제13권3호
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• pp.163-172
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• 1996

According to flying hours, aircraft engines require regular overhaul for preventive maintenance. Because of hostile defense environment of Republic of Korea, the aircraft of republic of Korea Air Force(ROKAF) have been operated at the maximum level of availability and have similar overhaul schedule in several months. The concentration of overhaul schedule in a short period demands additional spare engines far exceeding the spare engines for corrective maintenance. If ROKAF decides to purchase extra engines for the preventive maintenance, the extra engines will be used only for the preventive maintenance and will be excess inventory for the most of aircraft life ccle. Also, the procurement of extra engines is significant investment for ROKAF. To help ROKAF schedule the preventive maintenance without significant spending, this study develops a dynamic programming model that is solvable using an integer programming algorithm. The model provides the number of engines that should be overhauled for a month for multiple periods under given constraints. ROKAF actually used this model to solve a T-59 engine overhaul problem and saved about three billion won at one time. ROKAF plans to use this model continuously for T-59 and other weapon systems. Thus, saving for long term will be significant to ROKAF. Finally, with minor modification, this model can be applied to deciding the minimum number of spare engines for preventive maintenance.

• 대한산업공학회지
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• 제22권3호
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• pp.485-498
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• 1996

For a tree T rooted at a concentrator location in a telecommunication system, we assume that the capacity H for the concentrator is given and a profit $c_v$, and a demand $d_v$, on each node $\upsilon$ of T are also given. Then, the capacitated subtree of a tree problem (CSTP) is to find a subtree of T rooted at the concentrator location so as to maximize the total profit, the sum of profits over the subtree, under the constraint satisfying that the sum of demands over the subtree does not exceed H. In this paper, we develop a pseudopolynomial-time algorithm for CSTP, the depth-first dynamic programming algorithm. We show that a CSTP can be solved by our algorithm in $\theta$ (nH) time, where n is the number of nodes in T. Our algorithm has its own advantage and outstanding computational performance incomparable with other approaches such as CPLEX, a general integer programming solver, when it is incorporated to solve a Local Access Telecommunication Network design problem. We report the computational results for the depth-first dynamic programming algorithm and also compare them with those for CPLEX. The comparison shows that our algorithm is competitive with CPLEX for most cases.

• Management Science and Financial Engineering
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• 제1권1호
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• pp.21-37
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• 1995

This paper suggests a procedure of decomposing a multi-stage dynamic location problem into stages with respect stage. The problem can be formulated as a mixed integer programming problem, which is difficult to be solved directly. We perform a series of transformations in order to divide the problem into stages. In the process, the assumption of PSO (production-system-only) plays a critical role. The resulting subproblem becomes a typical single-stage dynamic location problem, whose efficient algorithms have been developed efficiently. An extension of this study is to find a method to integrate the solutions of subproblems for a final solution of the problem.

• 한국음향학회지
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• 제3권1호
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• pp.25-35
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• 1984

This paper analysis the Dynamic Time Warping algorithms for time normalization of speech pattern and discusses the Dynamic Programming algorithm for spoken Korean isolated digits recognition. In the DP matching, feature vectors of the reference and test pattern are consisted of first three formant frequencies extracted by power spectrum density estimation algorithm of the ARMA model. The major differences in the various DTW algorithms include the global path constrains, the local continuity constraints on the path, and the distance weighting/normalization used to give the overall minimum distance. The performance criterias to evaluate these DP algorithms are memory requirement, speed of implementation, and recognition accuracy.

• 연구논문집
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• 통권22호
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• pp.21-26
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• 1992

Dynamic analysis is important in structural design of SCARA or articulated type industrial robots and is' usually done to main three axes. In this paper, robot arm dynamics was analyzed using FBD(free body diagram). Though the proposed scheme becomes complex as DOF(degree of freedom)increases, it allows to see types and directions of forces and moments acting on the body. Therefore, the strength analysis of robot arm can be done relatively easy in a case of either closed or open loop chain. This method can be used for obtaining dynamic simulation at off-line programming system and calculating required torques at joints at on-line system.

• Journal of applied mathematics & informatics
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• 제27권1_2호
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• pp.245-257
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• 2009

A mixed type dual for multiobjective variational problem involving higher order derivatives is formulated and various duality results under generalized invexity are established. Special cases are generated and it is also pointed out that our results can be viewed as a dynamic generalization of existing results in the static programming.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.137-141
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• 1999

In this paper, we developed a Windows 95 version off-line programming system which can simulate a track vehicle model in 3D graphics space. The track vehicle was adopted as an objective model. The interface between users and the off-line program system in the Windows 95's graphic user interface environment was also studied. The developing language is Microsoft visual C++. Graphic libraries, OpenGL, by Silicon Graphics, Inc. were utilized for 3D Graphics.