• Advances in Computational Design
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• 제4권3호
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• pp.223-238
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• 2019

This study investigated the ultimate lateral load capacity of shear walls constructed with several types of structural foam sheathing. Sixteen tests were conducted and the results were compared to the published design values commutated by the manufactures for each test series. The sheathing products included 12.7 mm (1/2 in) SI-Strong, 25.4 mm (1 in) SI-Strong, 12.7 mm (1/2 in) R-Max Thermasheath, and 2 mm (0.078 in) ThermoPly Green. The structural foam sheathing was attached per the manufacturers' specification to one side of the wood frame for each wall tested. Standard 12.7 mm (1/2 in) gypsum wallboard was screwed to the opposite side of the frame. Simpson HDQ8 tie-down anchors were screwed to the terminal studs at each end of the wall and anchored to the base of the testing apparatus. Both monotonic and cyclic testing following ASTM E564 and ASTM E2126, respectively, were considered. Results from the monotonic tests showed an 11 to 27 percent smaller capacity when compared to the published design values. Likewise, the test results from the cyclic tests showed a 24 to 45 percent smaller capacity than the published design values and did not meet the seismic performance design criteria computation.

• 한국항해항만학회지
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• 제33권3호
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• pp.215-220
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• 2009

컨테이너 크레인은 강풍으로부터 보호를 받기 위한 차폐물이 없는 곳에 존재하기 때문에 이상 기후 조건에 취약성이 있는 구조물이다. 본 연구에서는 붐 각도의 변화에 따라 풍동실험과 전산유동 해석을 사용하여 컨테이너 크레인의 구조물에 대한 풍하중의 영향을 수행하였다. 그리고 75m/s의 풍속을 컨테이너 크레인에 적용하였다고 가정하였을 때 컨테이너 크레인의 풍력 내구성 설계에 사용되는 데이터를 컨테이너 크레인 설계자에게 제공하고자 한다. 본 연구에서는 건축물 하중기준의 풍하중 설계기준에 따라 풍하중을 적용하였으며 풍향에 따른 영향을 분석하기 위해서 유동장을 $10^{\circ}$ 간격으로 분할하였다. 이를 바탕으로 풍동실험과 전산 유동해석을 수행하였으며 얻어진 결과들을 비교 연구함으로써 컨테이너 크레인의 구조설계에 필요한 풍하중을 분석하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2007년도 추계학술대회 및 제23회 정기총회
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• pp.228-229
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• 2007

컨테이너 크레인은 강풍으로부터 보호를 받기 위한 차폐물이 없는 곳에 존재하기 때문에 이상 기후 조건에 취약성이 있는 구조물이다. 본 연구에서는 풍향변화에 따라 컨테이너 크레인에 작용되는 풍하중을 분석하기 위하여 수행되었다 사용된 모델은 61톤 급 컨테이너 크레인으로 현재 항만시설에 많이 사용되는 모델이다. 유동장은 원통으로 모델링하였으며, 직경 500m, 높이 200m로 설정하였다. 본 연구에서는 건축물 하중기준의 풍하중 설계기준에 따라 풍하중을 적용하였으며 풍향에 따른 영향을 분석하기 위해서 유동장을 10$^{\circ}$간격으로 분할하였다. 이를 바탕으로 CFX-10을 사용하여 전산유동해석을 수행하고 이를 통하여 얻어진 결과와 풍력실험 결과를 비교 연구함으로써, 컨테이너 크레인의 구조설계에 필요한 풍하중을 분석하였다.

• 한국항해항만학회지
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• 제32권3호
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• pp.251-255
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• 2008

컨테이너 크레인은 강풍으로부터 보호를 받기 위한 차폐물이 없는 곳에 존재하기 때문에 이상 기후 조건에 취약성이 있는 구조물이다. 본 연구에서는 풍향변화에 따라 컨테이너 크레인에 작용되는 풍하중을 분석하기 위하여 수행되었다. 사용된 모델은 61톤 급 컨테이너 크레인으로 현재 항만시설에 많이 사용되는 모델이다. 유동장은 원통으로 모델링하였으며, 직경 500m, 높이 200m로 설정하였다. 본 연구에서는 건축물 하중기준의 풍하중 설계기준에 따라 풍하중을 적용하였으며 풍향에 따른 영향을 분석하기 위해서 유동장을 $10^{\circ}$ 간격으로 분할하였다. 이를 바탕으로 CFX-10을 사용하여 전산유동해석을 수행하고 이를 통하여 얻어진 결과와 풍력실험 결과를 비교 연구함으로써, 컨테이너 크레인의 구조설계에 필요한 풍하중을 분석하였다.

• 드라이브 ㆍ 컨트롤
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• 제12권1호
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• pp.9-14
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• 2015

In the early of 1950, the high response magnetic torque motor was developed for driving electro-hydraulic servo valves. Since then it has been broadly used for industrial application and the research of development or improvement of the torque motor is still being conducted. The purpose of this study is to present useful design criteria for the torque motor design. For this, torque motor is modelled and linearized. The static characteristics of the torque motor are investigated by direct computation of the derived linearlized equations. The dynamic characteristics of the torque motor are investigated with the derived transfer function by using Matlab and compared with the results of the linearlized analysis by using AMESim simulation with actual values of the physical parameters. Finally, the design criteria obtained from the analysis are reviewed.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1533-1537
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• 2005

The recent rainfall has happened to exceed the design rainfall after 1990 often, due to the characteristic of the rain to be changed. So, it is failing the ability safety of flood defense equipments to exist. This study analyzed the rainfall of Busan in 2003 since 1961 through the FARD2002(Frequency Analysis of Rainfall Duration). The result is equal to the thing which the design rainfall increased a little since 1991. The change of design rainfall created the result to be a flood discharge increase. This study investigated about the impact to influence on the river bank according to the change of flood discharge, the rainfall pattern change as well. This study used the program of HEC-RAS with HEC-HMS and calculated flood discharge with flood level of river. The result is equal to the thing which the computation became a flood level which exceed 50year(River design criteria-Korea water resources association 2002) criteria with 30year(River establishment criteria-Ministry of construction & transportation 1993), because of an area of impermeability increased of model basin.

• 오토저널
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• 제5권1호
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• pp.54-62
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• 1983

This paper presents structural analyses performed on the white body of vehicle using the most competitive analyzer, Finite Element Method, and attempts to obtain design criteria of body. By applying the substructure and restart technique to structural model, computation time is reduced. The synthetic processing from modelling to graphic visualization is accomplished by several subprograms, viz., various pre-post processors. On the basis of home-made vehicle modeling, typical cases of accident and service load is analyzed and discussed. The results obtained will guide the designer to design the structure optimally.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.1212-1221
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• 1993

The shape optimization procedure applying finite element method was carried out for the specific purpose of analysis of a tractor chassis frame. Minimization of the mass as an objective function is executed under multiple constrained conditions of nodal displacements and stresses. The optimization process executions were succeeded in converging into single optimum solution. Although mass reduction and stress alleviation were attained by 40% and 26 to 24% respectively , the geometry of the shape is so complicated for fabrication that the refinement of the geometry is of necessity.

• Steel and Composite Structures
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• 제1권4호
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• pp.411-426
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• 2001

This paper treats the failure analysis of prestressing steel wires with different kinds of localised damage in the form of a surface defect (crack or notch) or as a mechanical action (transverse loads). From the microscopical point of view, the micromechanisms of fracture are shear dimples (associated with localised plasticity) in the case of the transverse loads and cleavage-like (related to a weakest-link fracture micromechanism) in the case of cracked wires. In the notched geometries the microscopic modes of fracture range from the ductile micro-void coalescence to the brittle cleavage, depending on the stress triaxiality in the vicinity of the notch tip. From the macroscopical point of view, fracture criteria are proposed as design criteria in damage tolerance analyses. The transverse load situation is solved by using an upper bound theorem of limit analysis in plasticity. The case of the cracked wire may be treated using fracture criteria in the framework of linear elastic fracture mechanics on the basis of a previous finite element computation of the stress intensity factor in the cracked cylinder. Notched geometries require the use of elastic-plastic fracture mechanics and numerical analysis of the stress-strain state at the failure situation. A fracture criterion is formulated on the basis of the critical value of the effective or equivalent stress in the Von Mises sense.

• 한국CDE학회논문집
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• 제22권2호
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• pp.110-117
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• 2017

Delaunay refinement algorithm is a classical method to generate quality triangular meshes when point cloud and/or constrained edges are given in two- or three-dimensional space. It computes the Delaunay triangulation for given points and edges to obtain an initial solution, and update the triangulation by inserting steiner points one by one to get an improved quality triangulation. This process repeats until it satisfies given quality criteria. The efficiency of the algorithm depends on the criteria and point insertion method. In this paper, we propose a method to accelerate the Delaunay refinement algorithm by applying geometric hashing technique called bucketing when inserting a new steiner point so that it can localize necessary computation. We have tested the proposed method with a few types of data sets, and the experimental result shows strong linear time behavior.