• Transactions on Control, Automation and Systems Engineering
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• 제4권2호
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• pp.130-139
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• 2002

In this paper, at first, we investigate existing algorithms for finding the minimum infinity-norm solution of consistent linear equations and then propose a new algorithm. The proposed algorithm is intended to includes the advantages of computational efficiency as well as geometric explicitness. As a practical application example, optimum trajectory planning for redundant robot manipulators is considered. Also, an efficient approach avoiding discontinuity in trajectory is proposed by resolving the non-uniqueness problem of minimum infinity-norm solution. To be specific, the proposed method for checking possible discontinuity does not need any other algorithms in checking the possibility of discontinuity while previous work needs specially designed checking courses. To show the usefulness of the proposed techniques, an example calculating minimum infinity-norm solution for comparing the computational efficiency as well as the trajectory planning for a redundant robot manipulator are included.

• Earthquakes and Structures
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• 제10권3호
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• pp.563-588
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• 2016

In this study, solution models are proposed to obtain code-compatible ground motion record sets which can be used for both uni-directional and bi-directional dynamic analyses. Besides scaled, unscaled ground motion record sets are obtained to show the utility and efficiency of the solution models. For scaled ground motion sets the proposed model is based on hybrid HS-Solver which integrates heuristic harmony search (HS) algorithm with the spreadsheet Solver add-in. For unscaled ground motion sets HS based solution model is proposed. Design spectra defined in Eurocode-8 for different soil types are selected as target spectra. The European Strong Motion Database is used to get ground motion record sets. Also, a sensitivity analysis is conducted to evaluate the effect of different HS solution parameters on the solution accuracy. Results show that the proposed solution models can be regarded as efficient ways to develop scaled and unscaled ground motion sets compatible with code-based design spectra.

• 한국정보통신학회논문지
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• 제15권12호
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• pp.2687-2696
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• 2011

해양 센서 네트워크에서 클러스터링 문제는 네트워크 수명 및 확장성을 향상시키기 위한 문제 중 하나이다. 본 논문은 모든 노드가 클러스터 헤더를 통하여 싱크 노드로 데이터를 전송하는데 사용되는 전송 에너지를 최소화할 수 있는 클러스터링 문제의 최적 결과를 찾는 알고리즘을 제안한다. 일반적으로 네트워크에서 노드의 수가 증가하면 적절한 클러스터 구성을 위한 계산량은 급격히 늘어나게 된다. 본 논문에서는 적정한 시간 내에 최적의 클러스터 구성을 위한 유전 알고리즘을 제안하며, 효율적인 검색을 위해 유전 알고리즘의 효과적인 이웃해 생성 동작을 제안한다. 제안된 알고리즘은 전송 에너지와 실행시간 관점에서 성능을 평가하며, 평가 결과에서 제안된 알고리즘이 해양 센서 네트워크에서 클러스터를 효과적으로 구성함을 보인다.

• Communications for Statistical Applications and Methods
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• 제16권3호
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• pp.409-419
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• 2009

본 연구에서는 영상흐림보정를 위한 EM 알고리즘의 일반형 해를 제공한다. 주어진 관측영상의 크기가 크거나 많은 반복을 필요로 할 때, EM 알고리즘의 반복은 매우 오랜시간이 걸리며 비실용적이다. 본 연구에서는 복원 영상의 유효영역 밖에서 약간의 근사로부터 해를 일반형으로 나타내고, 이것을 이산형 유한 푸리에 변환을 이용하여 EM 알고리즘의 반복과정을 사용하지 않으면서 매우 유효한 복원영상을 즉시 계산하는 방법을 제공한다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.399-400
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• 2002

A numerical procedure for analyzing thermo-elastic contact applied to an automotive disk brake and calculating subsurface stress distribution has been developed. The proposed procedure takes the advantage of the simplex algorithm to save computing time. Flamant's solution and Boussinesq's solution are adopted as Green function in analysis. Comparing the numerical results with the exact solutions has proved the validity of this procedure.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.554-558
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• 2001

In this study, a hybrid method is used to search the pseudo-optimal solution for the I-dimentional nesting problem. This method is composed of the genetic algorithm for the global search and a simple heuristic one for the local search near the pseudo optimal solution. Several simulation results show that the hybrid method gives very satisfactory results.

• Communications for Statistical Applications and Methods
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• 제5권3호
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• pp.581-589
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• 1998

An algorithm is proposed for the $L_1$-estimation with linear equality and inequality constraints in linear regression model. The algorithm employs a linear scaling transformation to obtain the optimal solution of linear programming type problem. And a special scheme is used to maintain the feasibility of the updated solution at each iteration. The convergence of the proposed algorithm is proved. In addition, the updating and orthogonal decomposition techniques are employed to improve the computational efficiency and numerical stability.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.238-242
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• 1994

Shuster's algorithm for spin-axis determination is extended to include sensor bias and mounting angle as its solve-for parameters. The relation between direct and derived measurements bias is obtained by linearizing their kinematic equations. A one-step least-square estimation technique referred to as the 'closed form' solution is used, and the solution provides a more refined and decent initial guess for the subsequent filtering process contained within the differential correction module. The modified algorithm is applied for attitude determination of a GEO communication satellite in transfer orbit, and its results are presented.

• Journal of applied mathematics & informatics
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• 제6권3호
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• pp.757-770
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• 1999

We analyse in this paper the possibility of using preconditioning techniques as for square non-singular systems, also in the case of inconsistent least-squares problems. We find conditions in which the minimal norm solution of the preconditioned least-wquares problem equals that of the original prblem. We also find conditions such that thd Kaczmarz-Extendid algorithm with relaxation parameters (analysed by the author in [4]), cna be adapted to the preconditioned least-squares problem. In the last section of the paper we present numerical experiments, with two variants of preconditioning, applied to an inconsistent linear least-squares model probelm.

• 대한전자공학회논문지
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• 제25권7호
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• pp.746-758
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• 1988

This paper proposes a code scheduling algorithm which gives a software solution to the pipeline interlock. This algorithm provides a heuristic solution by recordering the instructions, instead of using hardware interlock mechanism when pipeline interlock prevents the execution of a machine instruction in a pipelined architecture. Program code size and overall execution time can be reduced due to the increased flexibility in the selection of instructions, which is possible from the alleviated ordering restriction on the use of conflict resources.