• 제목/요약/키워드: Engineering Problems

검색결과 16,744건 처리시간 0.049초

Unified approach to continuous and discrete Nehari problems

  • Kwon, Oh-Kyu;Lee, Koon-Seok
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.581-585
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    • 1992
  • A unified approach to continuous and discrete-time Nehari problems, based on recently developed results by the authors for the one-block and Hankel-norm model reduction problems, is proposed. First, we derive discrete-time solutions in delta domain where numerical error is small and then we show that the derived form becomes same as the continuous form when the sampling interval approaches to zero.

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동일하지 않는 병렬기계 일정계획을 위한 휴리스틱 방법 (A Hueristic Algorithm for Nonidentical Parallel Machines Scheduling)

  • 전태웅;박해천
    • 산업경영시스템학회지
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    • 제23권59호
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    • pp.37-42
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    • 2000
  • The parallel machines scheduling problems is one of the combinatorial optimization problems that often occurs in the real world. This problem is classified into two cases, one of which is the case which processing time are identical and the other, nonidentical. Not so much researches have been made on the case that nonidentical parallel machines scheduling problem. This study proposes Tabu Search methods for solving parallel machines scheduling problems related to due dates: minimizing mean tardiness, minimizing the number of tardy jobs, minimizing the maximum tardiness.

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화학섬유공업의 동향과 과제 (The Trends and Problems to be Solved of the Synthetics Fibers' Industry)

  • 김광철
    • 산업경영시스템학회지
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    • 제13권22호
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    • pp.129-146
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    • 1990
  • The purpose of this paper is to study the trends and problems to be solved of the Synthetics Fibers` Industry. The major concern has been paid to the key ideas and practical methods to be needed in strengthening the competitive power of the Synthetics Fibers' Industry of korea over the world. In this article, the researcher is to analyze the tends of the Synthetics Fibers' Industry of Korea Japan, Southeast Asia, Europe and U.S.A. and finally the researcher is to provide the major ideas concerning the problems to be solved in Synthetics Fibers' Industry of Korea to ward the competitive world market.

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균질재료와 벌칙인자를 이용한 위상 최적설계 (Topology Optimization Using Homogenized Material and Penalty Factor)

  • 임오강;이진식
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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    • pp.3-10
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    • 1998
  • Optimization problems may be devided into geometry optimization problems and topology optimization problems. In this paper, a method using tile equivalent material properties prediction techniques of a particulate-reinforced composites is proposed for the topology optimization. This method makes use of penalty factor in order that regions with intermediate value of design variables can be penalized. The computational results being obtained from PLBA algorithm of some values of penalty factor are presented.

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Solution of periodic notch problems in an infinite plate using BIE in conjunction with remainder estimation technique

  • Chen, Y.Z.
    • Structural Engineering and Mechanics
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    • 제38권5호
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    • pp.619-631
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    • 2011
  • This paper provides a complex variable BIE for solving the periodic notch problems in plane plasticity. There is no limitation for the configuration of notches. For the periodic notch problem, the remainder estimation technique is suggested. In the technique, the influences on the central notch from many neighboring notches are evaluated exactly. The influences on the central notch from many remote notches are approximated by one term with a multiplying factor. This technique provides an effective way to solve the problems of periodic structures. Several numerical examples are presented, and most of them have not been reported previously.

HRKPM을 이용한 키르히호프 판의 해석 (Kirchhoff Plate Analysis by Using Hermite Reproducing Kernel Particle Method)

  • 석병호
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2002년도 봄 학술발표회 논문집
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    • pp.12-18
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    • 2002
  • For the analysis of Kirchhoff plate bending problems, a new meshless method is implemented. For the satisfaction of the C¹ continuity condition in which the first derivative is treated as another primary variable, Hermite interpolation is enforced on standard reproducing kernel particle method. In order to impose essential boundary conditions on solving C¹ continuity problems, shape function modifications are adopted. Through numerical tests, the characteristics and accuracy of the HRKPM are investigated and compared with the finite element analysis. By this implementation, it is shown that high accuracy is achieved by using HRKPM fur solving Kirchhoff plate bending problems.

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A FINITE-ELEMENT METHOD FOR FREE-SURFACE FLOW PROBLEMS

  • Bai, Kwang-June;Kim, Jang-Whan
    • Journal of Theoretical and Applied Mechanics
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    • 제1권1호
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    • pp.1-27
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    • 1995
  • In this paper a finite element method for free-surface problems is described. the method is based on two different forms of Hamilton's principle. To test the present computational method two specific wave problems are investigated; the dispersion relations and the nonlinear effect for the well-known solitary waves are treated. The convergence test shows that the present scheme is more efficient than other existing methods, e.g. perturbation scheme.

비정형 고층 RC 건축물의 내진설계 시 문제점 (Problems in Seismic Design of High-Rise RC Building Structures having Irregularity)

  • 이한선;고동우
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 추계 학술발표회논문집
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    • pp.125-132
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    • 2003
  • This paper clarifies the problems which structural engineers would have when the high-rise reinforced concrete building structures with vertical and plan irregularities are to be designed against earthquakes. The most important problems appear to be as follows: (1) ambiguity in defining the principal direction of the structure and the dynamic base shear, (2) the methodology how to account for the accidental eccentricity when the modal analysis should be conducted as required for the torsionally irregular structures, and (3) the choice of 100/30 and SRSS methods to take into account the effect of the critical direction of earthquake.

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Abandoned Landfills in Indonesia and Their Problems

  • Ling, Marisa Mei;Park, Jun-Boum
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제14권4호
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    • pp.1-9
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    • 2009
  • This paper presents current condition of landfills in Indonesia and the problems exist. It also presents a review of study on abandoned landfill in Bandung, West Java where the actual problems can be seen and an insight to the solutions were developed.

사각형 판 유한 요소들의 정적 성능 비교 분석 I (Comparative Study on the Performance of Quadrilateral Plate Elements for the static Analysis of Limear Elastic structures( I );Displacements)

  • 이병채;이용주
    • 전산구조공학
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    • 제3권4호
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    • pp.91-104
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    • 1990
  • 사각형 판 유한요소의 정적 성능을 여러 가지 문제에 대한 수치 실험을 통해 비교 분석하였다. Kirchhoff이론과 Mindlin이론에 근거한 변위요소, 평형요소, Mixed 또는 Hybrid요소들을 대상으로 문헌조사를 통해 우수요소를 선정하였으며 사각형 판 문제, 마름모형 판 문제, 원형 판 문제, 외팔보형 판 문제를 다양한 격자, 경계조건에 대해 풀어 해를 비교하였다. Kirchhoff요소에서는 12자유도요소로 Armanios의 요소, 24 자유도 요소로 Watkins요소의 거동이 우수하였으나 전반적으로 Mindlin요소에 비해 거동이 떨어진다. Mindlin요소 중에서는 Hinton의 요소가 효율성, 수렴성, 신뢰성의 면에서 가장 우수하나 마름모형 판 문제나 뒤틀린 격자 문제등에서는 거동이 좋지 않으므로 계속 연구할 필요가 있다.

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