• Journal of Engineering Education Research
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• v.18 no.3
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• pp.24-32
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• 2015

The purpose of this research is to consider theoretical points of view on a preceding research related to an engineering design and abstract the definition of engineering design ability, its subdivision and element on the basis of experts' recognition. To achieve this goal, various literature researches were carried out by examining domestic and foreign articles in journals, lots of dissertations, and books related to engineering design through theoretical consideration. And to secure the validity on the definition of engineering design ability, its subdivision and element through the theoretical study, a feasibility evaluation method by the experts was applied. And the feasibility evaluation of the experts was conducted through 2 stages. The major conclusions of this study are as follows. Firstly, based on the experts' recognition on the definition of engineering design ability, its subdivision and element, which were revised through the 1st feasibility evaluation and then utilized in the 2st one, the validity was confirmed, and the subdivisions of the engineering design ability were divided into 5 and the elements of the subdivision ability were 33. Secondly, the engineering design ability was defined as "the one to design a realizable product with consumers' demand fully satisfying, based on a knowledge application ability, thinking ability, communication ability, problem-solving ability, and teamwork ability to solve engineering problems." Thirdly, the subdivisions of the engineering design ability were divided as a knowledge application ability, thinking ability, communication ability, problem-solving ability, and teamwork ability.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.9
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• pp.1373-1384
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• 1997

There have been a number of expert systems which are concerned with the design of machine elements such as gear, shaft, bearing and so on. However the design of more complicated systems such as gear dreives are still difficult. Thus, in consideration of the integrative nature of the system, we develop a design support system for gear drives which is composed of various machine elements-gear, shaft, bearing, key and so on. Design systems for each machine element are developed and integrated through object-oriented approach. Databases essential for data reference and/or data control in the design process are built up independently and interface to the main program. Expert systems are also developed and integrated for intelligent support to the designer, in those of the determination of gear specification and the selection of bearing types. Through the integration of design environment for each machine element, it is expected to increase the convenience in the design process and the stability of the design solution. And also the system management, including addition of various design/analysis modules and expansion to the gear drives of other types, can be conveniently achieved since the system has developed under due consideration of its efficiency and expandability through object-oriented programming approach.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.501-506
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• 2000

An iterative numerical computational algorithm is presented to design a plate or shell element subjected to membrane and flexural forces. Based on equilibrium consideration, equations for capacities of top and bottom reinforcements in two orthogonal directions have been derived. The amount of reinforcement is determined locally, i.e., for each sampling point, from the equilibrium between applied and internal forces. Based on nonlinear analyses performed in a hyperbolic cooling tower, the analytically calculated ultimate load exceeded the design ultimate load from 50% to 55% for an analysis with relatively low to high tension stiffening, cases $\gamma$=10 and 15. For these cases, the design method gives a lower bound on the ultimate load with respect to Lower bound theorem, This shows the adequacy of th current practice at least for this cooling tower shell case studied. To generalize the conclusion more designs - analyses should be reformed with different shell configurations.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.514-518
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• 2000

Micro wave seeker consists of a gimbal structure, a antenna and many RF parts. And Missile's propelling powers excite a gimbal structure, a antenna and many RF parts. Therefore, We must inquire into external forces to act on a micro wave seeker before everything. We must inquire into design parameters and then estimate dynamic characteristics of a gimbal structure with a finite element model to reflect part's characteristics for design for a gimbal structure in consideration of vibration features. In this paper, a gimbal structure of a micro wave seeker is modeled in finite element method and then updated by using the experimental modal data. Before we make a finite element model of a gimbal structure of a micro wave seeker, we make a finite element model of a sub-structure and compare with the experimental modal data.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.11
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• pp.54-63
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• 1997

The 1-D finite-element mehtod is applied for designing double-clad otpical fibers with dispersion-compensation capability. design parameters allowing only a $LP_{01}$ single mode are treated and macro-bending loss are taken into consideration. Design parameters are extracted to have the compensation ratio $(L_{SMF}/L_{DCF})$ of 6.2 for core structure with step-index profile, and of 5.2 for core with triangular-index profile.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.724-728
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• 1997

A CAD system of grid element for vacuum fluorescent disply has been developed. In order to reduce design man-houre and human erros, it is used to automate the design process using a knowledge base system. In the case of VFD product design, the most important consideration is the short-life cycle. So the development of CAD system for VFD product is needed. The developed system is based on the knowledge base system which is involved in a lot of expert's technology in the practice field. Using C-language under the HP-UNIX system, CIS customer language of the EXCESS CAD/CAM is used as the overall CAD environment. Results of this system will provide effective aids to the designer in this field

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.291-294
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• 2005

Recently, the usage of aluminum alloy is rapidly increasing in automobile industry to achieve weight reduction for fuel efficiency. However, design of forming process of aluminum is more difficult than steel because of poor formability and severe springback. Since applications of finite element analysis for the design of sheet metal forming process are actively performed, it is required to conduct proper consideration of aluminum material behavior. In this study, a plane stress yield function Yld2000(Yoon et al., 2000), proven to describe well the anisotropic behavior of aluminum alloy, is implemented for FE analysis. One element test is considered to verify the validity of implementation of Yld2000 model. In addition, cylindrical cup drawing test is performed to verify earing shape of a drawn cup.

• Advances in Computational Design
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• v.1 no.2
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• pp.195-206
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• 2016

Dams play a vital role in the development and sustainment in a country. Failure of dams leads to the catastrophic event with sudden release of water and is of great concern. Hence earthquake-resistant design of dams is of prime importance. The present study involves static, modal and transient analyses of dam-reservoir-foundation system using finite element software ANSYS 15. The dam and the foundation are modeled with 2D plane strain element "PLANE 42" and the reservoir by fluid acoustic element "FLUID 29" with proper consideration of fluid-structure interaction. An expression for the fundamental period of concrete dams is developed based on modal analysis. Seismic response of gravity dams subjected to earthquake acceleration is evaluated in terms of peak displacement and stress.

• Structural Engineering and Mechanics
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• v.14 no.2
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• pp.171-190
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• 2002

Two cases of design are performed for the hyperbolic paraboloid saddle shell (Lin-Scordelis saddle shell) and the hyperbolic cooling tower (Grand Gulf cooling tower) to check the design strength against a consistent design load, therefore to verify the adequacy of the design algorithm. An iterative numerical computational algorithm is developed for combined membrane and flexural forces, which is based on equilibrium consideration for the limit state of reinforcement and cracked concrete. The design algorithm is implemented in a finite element analysis computer program developed by Mahmoud and Gupta. The amount of reinforcement is then determined at the center of each element by an elastic finite element analysis with the design ultimate load. Based on ultimate nonlinear analyses performed with designed saddle shell, the analytically calculated ultimate load exceeded the design ultimate load from 7% to 34% for analyses with various magnitude of tension stiffening. For the cooling tower problem the calculated ultimate load exceeded the design ultimate load from 26% to 63% with similar types of analyses. Since the effective tension stiffening would vary over the life of the shells due to environmental factors, a degree of uncertainty seems inevitable in calculating the actual failure load by means of numerical analysis. Even though the ultimate loads are strongly dependent on the tensile properties of concrete, the calculated ultimate loads are higher than the design ultimate loads for both design cases. For the cases designed, the design algorithm gives a lower bound on the design ultimate load with respect to the lower bound theorem. This shows the adequacy of the design algorithm developed, at least for the shells studied. The presented design algorithm for the combined membrane and flexural forces can be evolved as a general design method for reinforced concrete plates and shells through further studies involving the performance of multiple designs and the analyses of differing shell configurations.

• Structural Engineering and Mechanics
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• v.60 no.3
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• pp.405-412
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• 2016

Bone is a living material with a complex hierarchical structure that gives it remarkable mechanical properties. Bone constantly undergoes mechanical. Its quality and resistance to fracture is constantly changing over time through the process of bone remodeling. Numerical modeling allows the study of the bone mechanical behavior and the prediction of different trauma caused by accidents without expose humans to real tests. The aim of this work is the modeling of the femur fracture under static solicitation to create a numerical model to simulate this element fracture. This modeling will contribute to improve the design of the indoor environment to be better safe for the passengers' transportation means. Results show that vertical loading leads to the femur neck fracture and horizontal loading leads to the fracture of the femur diaphysis. The isotropic consideration of the bone leads to bone fracture by crack propagation but the orthotropic consideration leads to the fragmentation of the bone.