• Structural Engineering and Mechanics
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• 제6권5호
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• pp.543-554
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• 1998

Space truss structures may be fabricated in any of several common grid configurations. With different configurations, the truss performance varies considerably affecting both its competitiveness and suitability for specific applications. The work presented in this paper is an assessment of the most commonly adopted truss configurations and their effect on truss characteristics such as the stiffness/weight value, member stress distribution, number of joints and members, degree of redundancy and cost. The study is parametric and covers wide variations of truss aspect ratios, boundary conditions and span/depth ratios. The results of this study could be of significant value to the design of space truss structures.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.123-128
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• 1998

This paper describes the evaluation of a force-reflecting interface with ultrasonic motors(USMs). The force-reflecting interface allows a human to feel object within virtual environment. To effectively display the mechanical impedance of the human hand we need a haptic device with specific characteristics, such as low inertia, almost zero friction and very high stiffness. USMs have attracted considerable attention as the actuator satisfied these conditions. USMs combine features such as high driving torque at low rotational speed, high holding torque and fast response therefore we studied two degree of freedom force-reflecting haptic system.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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• pp.119-125
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• 1997

The finite element analysis of plate and shell structures has been one of the major research interests for many years because of the technological importance of such structures. Quite often these structures are constructed by laminated composites. This is due to the high specific stiffness and strength of composite structures. The main objective of this paper is to extend the use of an improved degenerated shell element to the large displacement analysis of plates and shells with laminated composites. The total Lagrangian approach has been chosen for the definition of the deformation and the solution to the nonlinear equilibrium equations is obtained by the Newton-Raphson method.

• KCI Concrete Journal
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• 제12권1호
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• pp.79-89
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• 2000

This research developed an accelerated curing processe for cellulose fiber reinforced cement composites using vigorous reaction between carbon dioxide and cement paste. A wet-processed cellulose fiber reinforced cement system was considered. Carbonation curing was used to complement conventional accelerated curing. The parametric study followed by optimization investigation indicated that the carbonation curing can enhance the productivity and energy efficiency of manufacturing cellulose fiber reinforced cement composites. This also adds environmental benefits to the technical and economical advantages of the technology.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.927-932
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• 2001

Rubber has high damping and can be formed as various shape according to specific purpose. So, Rubber has widely used as isolation mounts. However, there are still a lot of difficulties in understanding of static and dynamic characteristics of compressed and shear rubber mounts. In this paper, Static characteristics of the rubber isolation mount are observed by the analytical method and FEM. Also dynamic characteristics of rubber mount under compression and shear strain are investigated.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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• pp.135-142
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• 2004

The apparent advantages of FRP (fiber reinforced plastics) composites over the conventional structural materials may be attributed to their high specific strength and stiffness. Other affordable properties of FRPs including an excellent durability make them particularly attractive for the structures in severe service conditions. Therefore, the material and sectional properties of a FRP structural component should be designed to meet its specific requirements and service conditions. This paper is performed the material property optimization under optimum design of pultruded FRP bridge deck section. In the problem formulation, an objective function is selected to minimize the maximum R(strength ratio). The thickness of layers, volumes of fibers and matrix fiber orientation, and stacking sequence of FRPs are used as the design variables. Strength ratio in the design code, material failure criteria and pultruded manufacture thickness are selected as the design constraints to enhance the material performance of FRP decks. From the results of the numerical investigation, we obtained the optimum deck section profile for conventional using object.

• 대한기계학회논문집
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• 제14권1호
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• pp.37-42
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• 1990

본 연구에서는 수직 밀링에서 탄소섬유 에폭시 복합재료를 절삭할 경우 절삭 조건에 따른 공구마멸 형태를 조사하였으며, 여유면 마멸량을 측정하여 Taylor 지수를 구하였다. 또한 절삭조건 및 측정 방향에 따른 표면거칠기를 조사하여 탄소섬유 에 폭시 복합재료의 가공특성을 조사하였다.

• 한국안전학회지
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• 제29권6호
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• pp.81-86
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• 2014

Composite materials have high specific stiffness, specific strength than existing concrete or steel materials. It has superior dynamic properties when utilizing advantages of material such as Non-corrosive, light weight, non-conducting and it has superior mold ability which can make variable shapes. Thus, in the construction, for using composite materials as construction materials, the study carried out static strength of fiber right angle direction and fatigue performance of FRP deck member. The study is going to deduct S-N curve by analyzing the results comparatively and estimate long-term durability. From now on, the study is going to provide interpretation of FRP member and basic data of design basis, furthermore providing foundation technique of composite materials' application of structural frame is the goal of this study.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 추계학술발표대회 논문집
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• pp.83-87
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• 2002

Aerospace industries are widely using honeycomb sandwich structures that it has high specific strength and stiffness, chemical material resistance and fatigue resistance. But, in repairing process of damaged areas, one of the problems is that delamination can be occurred in the sound areas during and/or after the exposure to the elevated curing temperature in case that the repair process is repeated. Therefore, this study was conducted Flatwise tensile, Drum peel and Long beam flexural strength tests to evaluate the degree of degradation of mechanical properties of the honeycomb sandwich structures by affecting thermal aging. As the results, the decrease of mechanical strength was observed at the specific specimen which is exposed over 50hrs at $127^{\circ}C$.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.49-52
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• 1999

Substituting composite structures for conventional metallic structures has many advantages because of higher specific stiffness and specific strength of composite materials. In this work, one-piece propeller shafts composed of carbon/epoxy composite and glass/epoxy one were designed and manufactured for a rear wheel drive automobile, which uses generally a steel two-piece propeller shaft. From the tests of the composite propeller shafts, it was found that the propeller shafts satisfied requirements of static torque transmission capability, torsional buckling capability and the first natural bending frequency and had 40% weight saving effect compared with steel propeller shaft.