• 제목/요약/키워드: special structure

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파랑에너지 집적 및 연안해역 제어를 위한 해저구조물의 설계 (Design of a Submerged Coastal Structure for Concentration of Wave Energy and Control of a Coastal Area)

  • 이중우;한스 크록
    • 한국항만학회지
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    • 제8권2호
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    • pp.37-56
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    • 1994
  • The effects of wave energy focusing by a submerged berm type of structure is examined. The fundamental idea is based on the phenomenon of refraction by a lens-shaped crescent structure which results in the focusing of wave energy on the center line of the structure. The shape of the submerged structure is a complex curve combining circular with elliptical elements. Based on the design procedure, a special configuration of structure(termed herein as a triple crescent structure) is introduced. Next, some hydraulic model tests are performed to confirm the wave focusing effect in laboratory. In addition, in order to interpret the wave focusing performance behind the structure, a numerical procedure by the hybrid element method is used on the basis of the conventional mild slope equation but modified and extended to allow for steeper bottom slopes and higher curvature. The modified refraction and diffraction provide additional mechanism for wave height amplification and the maximum amplification for triple crescent structure is presented. It also allows for the possibility of wave energy scattering with the change of the incident wave direction. Comparisons with previous theoretical results involving a submerged crescent shape structure are described.

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An Algorithm for Multiple Compensatory Objectives Problems

  • Yang, Kwang-Min
    • 한국경영과학회지
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    • 제7권2호
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    • pp.31-39
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    • 1982
  • This paper presents an efficient algorithm both in computation speed and storage requirement by exploring the special structure of problems involving multiple objective goals. The algorithm developed here is limited to the problems with multiple, compensatory objectives, however it can be extended to‘traditional’preemptive priority goat programming problems. Computational results are included.

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Survey of Traveling Salesman Problem

  • Kim, Chang-Eun
    • 산업경영시스템학회지
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    • 제13권22호
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    • pp.65-69
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    • 1990
  • Two different algorithms for traveling salesman problem(TSP) will be discussed. One is the engineering approach to the TSP. The other one is Branch-and-Bound algorithm to take advantage of the special structure of combinational problems. Also a generalization of TSP will be presented.

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Effects of face-sheet materials on the flexural behavior of aluminum foam sandwich

  • Xiao, Wei;Yan, Chang;Tian, Weibo;Tian, Weiping;Song, Xuding
    • Steel and Composite Structures
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    • 제29권3호
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    • pp.301-308
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    • 2018
  • Properties of AFS vary with the changes in the face-sheet materials. Hence, the performance of AFS can be optimized by selecting face-sheet materials. In this work, three types of face-sheet materials representing elastic-perfectly plastic, elastic-plastic strain hardening and purely elastic materials were employed to study their effects on the flexural behavior and failure mechanism of AFS systematically. Result showed face-sheet materials affected the failure mechanism and energy absorption ability of AFS significantly. When the foam cores were sandwiched by aluminum alloy 6061, the AFS failed by face-sheet yielding and crack without collapse of the foam core, there was no clear plastic platform in the Load-Displacement curve. When the foam cores were sandwiched by stainless steel 304 and carbon fiber fabric, there were no face-sheet crack and the sandwich structure failed by core shear and collapse, plastic platform appeared. Energy absorption abilities of steel and carbon fiber reinforced AFS were much higher than aluminum alloy reinforced one. Carbon fiber was suggested as the best choice for AFS for its light weight and high performance. The versus strength ratio of face sheet to core was suggested to be a significant value for AFS structure design which may determine the failure mechanism of a certain AFS structure.

복합상업시설 실내 공간구조와 매장구성 성향간 상관성 분석 - 2000년대 건립사례 저층부의 유형학적 분석을 중심으로 - (A Study on the Correlationship between Spatial Structure and Shop Composition in Mixed-Use Facilities - Focused on the Typological Analysis about Lower Part of the Facilities Built After the Year 2000 -)

  • 현창용
    • 한국실내디자인학회논문집
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    • 제26권6호
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    • pp.62-70
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    • 2017
  • This study has a purpose that definitize correlationship of spatial structure and sales strategies in mixed-use complexes which established in Korea since year 2000. For this purpose, this study tries to analysis spatial structure of mixed-use facilities through space syntax theory and makes an typological categorization based on their space composition. As a result of categorization, Korean mixed-use facilities can be classed as three types. First type is integrated stacking type. Second one is parallel connecting type. Third type is room to room type. According to differences between categories, their spatial structures show different meaning with different sales strategies. Integrated stacking type sales luxury brands and expensive stuffs and it also has deep and complicated structure. That means theses spaces usually make a strategy of exclusion. Parallel connecting type sales special categories and it also has shallow and easy spatial structure. That means these facilities want to make a smooth connection between apposed volumes. Room to room type sales cheap and fancy objects and it also has simple and shallow structure. That means simple spatial structure can be lead contact customer to stuffs. These results mean spatial structure have a effect on design of sales space.

A Study on Design Preference for the Sales Spaces of Duty-Free Shops by the Examination of Image Evaluation - Cases of Duty-Free Shops in Jeju Special Self-governing Province -

  • Moon, Jung-Eun;Kim, Bong-Ae
    • Architectural research
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    • 제12권2호
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    • pp.53-62
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    • 2010
  • The purpose of this study is to examine design preferences for the sales spaces of duty-free shops (DFSs) by conducting image evaluations. The results will help improve quality by influencing designs for the construction, extension or remodeling of these shops. An image measurement method, the semantic differential method, was used to measure cognitive structure using photos of shops. Photos were collected of the DFS at Jeju Island, as well as photos of brand stores designed by architects. Two sets of 16 photos (32 different photos in all) were selected according to photo classification standards and design concepts, both decided by reviewing previous studies and related materials. The evaluation and survey were done by two sets of subjects: sales employees, who have experience and special knowledge of the evaluation of sales space; and students majoring in architecture. To strengthen the evaluation results, I conducted a preliminary survey and a main survey, verifying and complementing findings. 116 surveys were conducted, of which 14 were of poor quality and rejected, leaving and 102 to be analyzed. The collected surveys were statistically analyzed, using SPSS 12.0 for Windows. Reliability, image profile, factor and multi-dimensional scaling analyses were conducted. As a result, image evaluation structure and characteristics were obtained for sales spaces of DFSs, confirming the difference between them and other spaces.

A Lagrangean Relaxation Method for the Zero-One Facility Location Problem with Uniform Customer Demands and Facility Capacities

  • Tcha, Dong-Wan;Yoo, Chun-Beon
    • 대한산업공학회지
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    • 제12권2호
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    • pp.21-31
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    • 1986
  • Consider a capacitated facility location problem in which the demands of customers are all equal and so are the capacities of facilities. Under the restriction that each customer's uniform demand be met by exactly one facility, the objective is to select a set of facilities to open, and to assign customer's demand to them so as to minimize the total cost which includes fixed costs of opening facilities as well as variable assignment costs. The problem is modelled as a pure zero-one program which may be viewed as a variant of well-known capacitated facility location problems. The purpose of this study is to develop efficient computational procedures for solving the pure zero-one facility location problems. Due to the special structure of our zero-one location problem with uniform demand, it can be converted to a location problem with the unimodular property. A Lagrangean relaxation algorithm is developed to solve the location problem. The algorithm is made efficient by employing a device which exploits the special structure of a surrogate constraint. The efficiency of the algorithm is analyzed through computational experiments with some test problems.

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로봇 메니플레이터의 레귤레이션 제어를 위한 개선된 적분 슬라이딩 모드 제어기 (An Improved Integral Sliding Mode Controller for Regulation Control of Robot Manipulators)

  • 이정훈
    • 전기학회논문지
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    • 제67권1호
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    • pp.103-113
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    • 2018
  • In this paper, an improved integral variable structure regulation controller is designed by using a special integral sliding surface and a disturbance observer for the improved regulation control of highly nonlinear rigid robot manipulators with prescribed output performance. The sliding surface having the integral state with a special initial condition is employed in this paper to exactly predetermine the ideal sliding trajectory from a given initial condition to the desired reference without any reaching phase. And a continuous sliding mode input using the disturbance observer is also introduced in order to effectively follow the predetermined sliding trajectory within the prescribed accuracy without large computation burden. The performance of the prescribed tracking accuracy to the predetermined sliding trajectory is clearly investigated in detail through the two theorems, together with the closed loop stability. The design of the proposed regulation controller is separated into the performance design and robustness design in each independent link. The usefulness of the algorithm has been demonstrated through simulation studies on the regulation control of a two-link robot under parameter uncertainties and payload variations.

막구조물의 막장력 측정장치 개발에 관한 연구 (DEVEOPMENT OF MEASURING SYSTEM OF MEMBRANE STRESS FOR MEMBRANE STRUCTURE)

  • 정한목;우재원;조병욱;이성연
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2008년도 춘계 학술발표회 논문집
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    • pp.171-178
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    • 2008
  • This paper is concerned with the development of a measurement system using field measuring device which will give the membrane stress of the membrane structures. Up to this point, several techniques on measurement of membrane stresses has been proposed and some have been used in the fields, but accuracy of the measured stresses to be far from reliable one. Such situation has not been changed until recent days, we do not have the measurement device on which we can depend. On top of that, due to the different properties in cross directions for material of the membrane, the stress in the warp direction is different from that in the fill one. A new method is proposed to measured membrane stresses in two different direction separately, where instead of membrane stresses directly, an external force perpendicular to the membrane to be applied. A portable device can measure the applied force and the displacement. A special testing bed to be fabricated to accommodate $50cm{\times}50$ manbrane specimen which can apply 5 ton load in two orthogonal direction. A special device using push-pull gage was developed. To measure the membrane stresses in warp and fill direction separately, a different length of the tips are used. The measuring device which can called tension meter, can be calibrated on the testing bed, and optimized the length and shape of tip.

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