• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.11
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• pp.1796-1801
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• 2001

For micro-machines, very few design methodologies based on optimization hale been developed so far. To overcome the difficulties of design optimization of micro-machines, the search method for multi-dimensional design window (DW)s is proposed. The proposed method is defined as areas of satisfactory design solutions in a design parameter space, using both continuous evolutionary algorithms (CEA) and the modified K-means clustering algorithm . To demonstrate practical performance of the proposed method, it was applied to an optimal shape design of micro electrostatic actuator of optical memory. The shape design problem has 5 design parameters and 5 objective functions, and finally shows 4 specific design shapes and design characters based on the proposed DWs.

• Journal of the Korean Society of Costume
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• v.53 no.6
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• pp.131-143
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• 2003

This treatise deals with the profitable suit image design of middle-aged men by examining visual effects in physical design. The sample of this study is people who lives in Kwangju, the Republic of Korea and 20-50 age's men and women. And it is very variety in each population statistics factors the differences of associate design visual effect which considering the difference of sex and age group, numbers of button, a figure and material pattern. Firstly, look into the associate design visual effect by sex and button number. In men's group, the style with three buttons was the most attractive and that with two buttons was the least attractive. In 50's group, the style with two buttons was the least attractive and those with 1.3 and 4 buttons were a little attractive. Secondly, in the difference of associate design with sex and shape, men's group was considered that standard type was the most attractive shape, women's group was thought that lean and standard types were the most attractive shape. So we can know that the attractive shape is different with sex. In the difference of association design with age and shape, 20's considered that standard type was the most modernistic and fat type was the least modernistic. 30's considered that lean type was the most modernistic and 50's thought that fat type and standard type were the most modernistic. Thirdly, see the sex and material pattern. In familarity, men's group considered that stripe pattern was more familiar than checks and plain patterns. And they considered that striped pattern and plain was more manly than checks. In sex and material pattern, 20's thought that plain was the most attractive, stripe was the next, and checks was not attractive. 40's estimated that plain and stripe were more attractive than checks. 50's judged that stripe was the most attractive material. Thus. the attraction is different with ages and material patterns.

• Journal of the Korean Society of Fashion and Beauty
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• v.4 no.4 s.10
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• pp.25-32
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• 2006

The purpose of this study is to analyze formative features of women shoes, to develop distinctive shoes design for coming fashion trend. the methods of this study are documentary research and case study. In the theoretical study, this study has catched the origin of shoes and the changes of shoes design of each era. for the study of formative features of women shoes in 1990's, 215 kinds of pictures have been selected from in professional shoes magazines. The results of analysis are as follow. Woman shoes categorized the design factors into shape, material, decoration. Reformational shape that reconstructs old shape of shoes by comtemporary aesthetic, shape in that dual images were mixed, re-created shape that was constructed through the reconstruction of structures and shapes of shoes. Material image was strengthened by varying patterns of unburned calf, leopard and zebra. Avant-garde was appeared by using naturalistic material to represent natural beauty or using merry, daring material. Post-modern tendency was appeared like using brassiere strap instead of back strap or using round string in elegant shoes.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.1
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• pp.48-54
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• 2004

This paper describes the development of automatic shape design program for spur gear. It produces automatically third-dimensional surface and solid model used in CAD/CAM system with inputting simple measurements. This program can maximize user's convenience and get surface and solid model quickly as accepting GUI(graphic user interface). Automatic shape design program for spur gear was developed by Visual LISP, a developer program. Besides, a geometrical method and a mathematical algerian are used in this program. Use frequency of a fine spur gear is on the increase recently and manufacture process of this gear is heat treatment after press processing with molding. In this press processing, the upper punch portion of a fine spur gear shape is drafted by CAM. Therefore, estimated that surface and solid model of spur gear used to CAM are needed in this research. In this research, after 2 ㎜ gear was modeled by auto shape design program, the upper punch portion of a fine spur gear was manufactured as giving third-dimensional model to CAM software and then, displayed the result as applying to press process.

• Journal of Korean Association for Spatial Structures
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• v.15 no.2
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• pp.51-59
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• 2015

In this study, a shape design and an analysis considering structural stability were investigated to develop an icosahedron-based hemispherical modular dome. To design this modular dome, a program that can perform icosahedron shape modeling, modularization of joint connection members, and the analysis of structural stability was developed. Furthermore, based on the adopted numerical model, the eigen buckling mode, unstable behavior characteristics according to load vector, and the critical buckling load of the modular dome under uniformly distributed load and concentrated load were analyzed, and the resistance capacities of the structure according to different load vectors were compared. The analysis results for the modular dome suggest that the developed program can perform joint modeling for shape design as well as modular member design, and adequately expressed the nonlinear behaviors of structured according to load conditions. The critical buckling load results also correctly reflected the characteristics of the load conditions. The uniformly distributed load was more advantageous to the structural stability than concentrated load.

• Journal of the Korea Society for Simulation
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• v.22 no.3
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• pp.81-87
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• 2013

This paper is about study how to decrese surge pressure that is occurred in excavator driving motor. We used computer simulation program SimulationX. It is also about the way finding design problem and approaching a solution through interpreting shape design sensitivity analysis. Programmes are below. First of all, finding shape fault by analyzing dynamic behavior of valves installed in hydraulic driving motor which is designed now. And drawing variable which is considered sensitive to improve dynamic efficiency among a lot of shape variables. Then, targeting that variable and examining dynamic efficiency stabilization tendency with controlling it. Finally, suggesting the most effective tuning method through variable combination as there are a lot of sensitive variables.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.12-20
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• 1999

In this paper, method for mapping a three-dimensional shape into the two-dimensional plane will be introduced. This method is referred to geometric modelling and means a transformation between the flat sheet and final surface. The initial blank shape represents the original configuration of the final shape formed into three dimensional surface. The initial constant constant area mapping hypothesis was used in this paper. This technique will be applied to the basic data for an interactive computer design capable of dealing with typical stamping process, including deep parts and complex shapes.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.531-536
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• 2001

The structural shape optimization is a useful tool for engineers to determine the shape of a structure. During the optimization process, relocations of nodes happen successively. However, excessive movement of nodes often results in the mesh distortion and eventually deteriorates the accuracy of the optimum solution. To overcome this problem, an efficient method for the shape optimization has been developed. The method starts from the design domain which is large enough to hold the possible shape of the structure. The design domain has pre-defined uniform fine meshes. At every cycle, the method judges whether all the elements are inside of the structure or not. Elements inside of the structure are assigned with real material properties, however elements outside of the structure are assigned with nearly zero values. The performance of the method is evaluated through various examples.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.172-175
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• 2007

The Performance of a PEMFC stack is strongly dependent on the uniform reactants distribution on MEA. The uniform distribution can be achieved by flow-field pattern and manifold design optimized to satisfy operating conditions. This paper investigates uniform reactants distribution in channels by changing manifold shape and inlet mass flow rate. Typical U and Z shape and modified U and Z shape manifolds with buffer zone were designed. To check the uniform reactants distribution, standard deviation of mass flow rate was compared. The numerical results show that the inlet mass flow rate, inlet shape, and manifolds shape are critical factor for uniform distribution.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.40-45
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• 2001

The relationship between structural geometry and number of life cycles to failure is investigated to improve the fatigue life of structural components. The linear elastic fracture mechanics(LEFM) approach is integrated with shape optimal design methodology. The primary objective of this study is to decide an optimal shape for enhancing the life of the structure. The results from LEFM analyses are used in the fatigue model to predict the life of the structure before failure is occurred. The shape of the structure is optimized by using the growth strain method. Relevant issues such as problem formulation, finite element modeling are explained. Three design examples are solved, and the results show that, with proper shape changes, the life of structural systems subjected to fatigue loads can be enhanced significantly.