• 경영과학
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• 제24권2호
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• pp.73-80
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• 2007

Robust Design(RD) is a cost-effective methodology to determine the optimal settings of control factors that make a product performance insensitive to the influence of noise factors. To better facilitate the robust design optimization, a dual response surface approach, which models both the process mean and standard deviation as separate response surfaces, has been successfully accepted by researchers and practitioners. However, the construction of response surface approximations has been limited to problems with only a few variables, mainly due to an excessive number of experimental runs necessary to fit sufficiently accurate models. In this regard, an innovative response surface approach has been proposed to investigate robust design optimization problems with larger number of variables. Response surfaces for process mean and standard deviation are partitioned and estimated based on the multi-level approximation method, which may reduce the number of experimental runs necessary for fitting response surface models to a great extent. The applicability and usefulness of proposed approach have been demonstrated through an illustrative example.

• 한국기계가공학회지
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• 제1권1호
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• pp.133-140
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• 2002

The object of this paper is to predict the surface roughness using the experiment equation of surface roughness, which is developed with a full factorial design in turning. $3^3$ full factorial design has been used to study main and interaction effects of main cutting parameters such as cutting speed, feed rate, and depth of cut, on surface roughness. For prediction of surface roughness, the arithmetic average (Ra) is used, and stepwise regression has been used to check the significance of all effects of cutting parameters. Using the result of these, the experimental equation of surface roughness, which consists of significant effects of cutting parameters, has been developed. The coefficient of determination of this equation is 0.9908. And the prediction ability of this equation was verified by additional experiments. The result of that, the coefficient of determination is 0.9718.

• 한국생산제조학회지
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• 제22권6호
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• pp.1018-1024
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• 2013

In the process of draw die design for stamping automotive press panels, the addendum surfaces generated in metal forming simulation software cannot be used in downstream processes such as machining and making draw dies because simulation tools use simple discrete models for the surface geometry. The downstream processes require more precise and continuous geometric models such as NURBS surfaces. Generally, automotive die engineers manually regenerate the addendum surface geometry using the discrete model. This paper presents an automated geometric modeling process for generating addendum surfaces using draft surface models. The design parameters of the section curve for the addendum surfaces are extracted automatically from the draft geometry. Using the extracted design parameters, smooth addendum surfaces are generated automatically as NURBS surfaces. The generated surfaces are $G^1$ continuous with the part surface and the binder surface, and can be used in downstream processes.

• 한국결정성장학회지
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• 제27권4호
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• pp.212-219
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• 2017

앞으로 다가올 감성이 지배하는 '하이터치(High-Touch)'의 시대에 걸맞은 사람이 되기 위해서는 6가지 능력이 중시되는데 디자인, 스토리, 조화, 공감, 놀이, 의미가 있으며 이 중에서 디자인과의 조화를 가장 중요한 능력으로 꼽았다. 모든 비즈니스의 기본요소라고 볼 수 있는 디자인은 논리적이고 객관화된 정보와 지식을 바탕으로 만들어진 현대의 디자인 관으로는 직관적이고 감성적인 앞으로의 시대 흐름에 발맞추기 힘들 것이다. 본 논문은 1차적 관점의 디자인 소재 중요성과 함께 심도 있는 Color, Material, Finishing(CMF) 이해와 차별화 전략을 세워 소비자가 느끼는 감성인지요소와 제품의 표면처리디자인 적용을 통한 대품질, 매력품질, 감동품질을 만족시키는 감성 표면처리디자인의 체계화 및 표준화를 제시하였다. 제품에 적용되어지는 부품 유형별 CMF 차별화 전략 방향 설정에 따라 구현가능성 차별성 신표면처리특성 효율성을 고려하여 시각적 표면처리 샘플로 구현하였다. 이를 통해 향후 실질적으로 제품 개발 시 IT 및 전자제품 분야와 그 이상의 분야에서 디자이너, CMF 디자이너, 표면처리전문가, 엔지니어 등 실무 환경에서의 대상제품, 부품유형, 적용소재, 적용표면처리, 표면컬러, 표면질감, 구현하고자하는 느낌 등 통합적 요소들을 이해하고 공유할 수 있는 실무자 소통연계 툴 및 감성 표면처리디자인 전략적 접근 프레임워크로서의 활용이 예상되는 바이다.

• 대한기계학회논문집A
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• 제24권4호
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• pp.894-900
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• 2000

Optimization of chassis frame is performed according to the minimization of eleven responses representing one total frame weight, three natural frequencies and seven strength limits of chassis frame that are analyzed by using each response surface model from D-optimal design of experiments. After each response surface model is constructed form D-optimal design and random orthogonal array, the main effect and sensitivity analyses are successfully carried out by using this approximated regression model and the optimal solutions are obtained by using a nonlinear programming method. The response surface models and the optimization algorithms are used together to obtain the optimal design of chassis frame. The eleven-polynomial response surface models of the thirteen frame members (design factors) are constructed by using D-optimal Design and the multi-disciplinary design optimization is also performed by applying dual response analysis.

• 한국생산제조학회지
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• 제26권3호
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• pp.292-298
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• 2017

Numerical analysis for various design parameters should be preceded by optimal design of composite materials. Numerous studies have been conducted on the bolting of interconnecting beams. In this study, the response surface method was applied to optimize the design of bolted joints connected by laminated wood composite beams. The response surface was created by combining the FEA code for composite analysis and the algorithm for forming the response surface. Optimization on this response surface was performed with a genetic algorithm to derive the results. The determination of the optimum bolt-hole position for the connection of composite beams is an optimization problem. Tsai-Wu composite failure index, maximum deflection, and simple von Mises stress are set as the objective functions. It has been proved that the design results of the optimized bolt-hole are superior to the design performance of the existing conventional bolt-hole position.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2008년도 춘계학술발표대회 논문집
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• pp.36-38
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• 2008

The purpose of the study is to propose a new surface design concepts within fractal pattern. In this study, I am offering the fractal concepts drawn from science, as a new anchoring point for surface design. Fractal Patterns are generated by transforming a seed slab into a number of constituent elements through fractal operations of rotation, scaling and linear transformations. These elements are bound together as a second generation seed shape which is reiterated according to the same transformations. This process continues for as many generations as desired. In conclusion, this study places a great emphasis on the natural pattern order to the surface generation, which I hope will contribute to generating a number of creative possibilities for interior design.

• 한국의류학회지
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• 제28권11호
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• pp.1536-1543
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• 2004

Garment is made by a 2D pattern and should be fitted to a human body which has 3D characteristics. Therefore, to design a pattern more effectively, the use of 3D information of a human body and the investigation of relationship between the 3D garment and 2D pattern are necessary. In this work, ruled surface method was used to reflect the 3D information of a human body for a pattern design. The images of the brassiere line on the woman's dress form were captured by phase-shifting projection moire system and the 3D information on the design line was obtained. 2D patterns on the various parts of the brassiere were developed directly from the 3D data by the ruled surface method. In addition, design line, the area and the amount of dart were quantified. And then we verify the appropriateness of the ruled surface method to the 2D pattern development by measuring the distribution of the space between women's figure and segmented clothing item. It was found that the ruled surface method is useful to transform the 3D design line to the 2D pattern, if we followed the steps suggested in this paper.

• 한국정밀공학회지
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• 제12권2호
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• pp.112-122
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• 1995

While many surfaces such as automobile outer panels, ship hulls and airfoils are characterized by their smooth, free-form shapes, a far larger class of functional surfaces are characterized by highly irregular, multi-featured shapes consisting of pockets, channels, ribs, etc. In constaract to the design of aesthetic, free-form surfaces, functional surface design can perhaps best be viewed as a process of assembling a collection of known component surfaces to form a single compound surface. In this paper, we presents a feature-based functional surface modeling method. A single feature involves a secondary surface, which we must join to a primary surface with a smooth transition between two boundary courves. Through recursive blending of a secondary surface with the primary surface, the mullti-featured surface is represented. After constructing a compound surface, we generate the Z-map for NC machining of the surface. Offsetting the Z-map using the inverse offsetting technique, we get CL tool paths with out gouging.

• International Journal of Fluid Machinery and Systems
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• 제2권3호
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• pp.223-231
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• 2009

Experimental investigations were conducted for the internal flows of the axial flow stator and diagonal flow rotor. Corner separation near the hub surface and the suction surface of stator blade are mainly focused on. For the design flow rate, the values of the axial velocity and the total pressure at stator outlet decrease between near the suction surface and near the hub surface by the influence of corner wall. For the flow rate of 80-90% of the design flow rate, the corner separation of the stator between the suction surface and the hub surface is observed, which becomes widely spread for 80% of the design flow rate. At rotor outlet for 81% of the design flow rate, the low axial velocity region grows between near the suction surface of rotor and the casing surface because of the tip leakage flow of the rotor.