• Korean Journal of Mathematics
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• 제25권3호
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• pp.405-435
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• 2017

We deal with a sensitivity analysis of an optimal shape control problem for the stationary Navier-Stokes system. A two-dimensional channel flow of an incompressible, viscous fluid is examined to determine the shape of a bump on a part of the boundary that minimizes the viscous drag. By using the material derivative method and adjoint variables for a shape sensitivity analysis, we derive the shape gradient of the design functional for the model problem.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 춘계학술대회논문집
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• pp.16-22
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• 1996

Two kinds of blank shapes, optimum and square, are adopted to investigate formbility. Optimum blank shape is determined to construct an L-shape cup with uniform height and without flange part. For this purpose , rigid-plastic FEM analysis is applied with backward tracing technique. Maximum cup detph and strain distribution are measured experimetally for the products of the two kinds of blank shapes, which are optimum and square.It is confirmed that deeper cup without severe thickness reduction can be obtained fro the optimum shape.

• 한국정밀공학회지
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• 제22권4호
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• pp.194-202
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• 2005

The objective of this paper is to develop a multi-functional hotwire cutting system (MHC) using EPS-foam block or plate as the working material. Because the MHC apparatus employs a four-axis synchronized hotwire cutter with the structure of two XY movable heads and a turntable, it allows the easy fabrication of various 3D shapes, such as (1) an axisymmetric shape or a sweeping cross-sectioned pillar shape using the hot-strip in the form of sweeping surface and EPS foam block on the turntable, (2) a polyhedral complex shape using the hotwire and EPS foam block on the turntable, and (3) a ruled surface approximated freeform shape using the hotwire and EPS foam plate. In order to examine the applicability of the developed MHC apparatus, an axisymmetric shape, a polyhedral shape and a large-sized freeform shape were fabricated on the apparatus.

• International Journal of Industrial Entomology and Biomaterials
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• 제41권1호
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• pp.11-14
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• 2020

This work was preliminary report on the shape of mulberry fruits and mulberry flowers. The shape of mulberry was varied with mulberry cultivars as bended oval shape (Daeshim), oval shape (Gwasang No. 2), oval-cylindrical shape (Sagyeppong), uneven heart shape (Suwonppong), and roundish shape (Cheonggangsang). The style of female flowers was also varied with cultivars as no style (Palchung), short style (Gwasang No. 2), cone style (Susungppong), and rectangular style (Daedangsang). This observation suggested that the shape and flower of mulberries are different among mulberry cultivars. It needs to further systematic study to know the shape and flower of mulberry cultivars and to elucidate the relationship between the morphological characters and mulberry cultivars.

• 복식문화연구
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• 제15권2호
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• pp.252-264
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• 2007

The purpose of this study was to compare two analytical methods classifying foot shape. The methods compared were cluster analysis method and foot index analysis method. This study defined the women's foot shape by these methods. 39 foot measurements which were automatically collected using the three dimensional foot scanner were analyzed. 203 Korean women in age 20s were participated in the anthropometric survey. Their foot shapes were classified into 5 foot types by cluster analysis: short & slim shape, flat shape, short & slender shape with slightly distorted toe, long and big shape, and short & wide shape. The foot measurements were also analyzed by the ratio of foot width and length. Five foot types that were classified by cluster analysis and three foot types that were classified by the foot index were compared. The comparison shows that cluster analysis precisely defined foot shapes. It was suggested that made-to-measure shoes making industry may adopt the foot shape analysis method utilizing cluster analysis.

• 한국통신학회논문지
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• 제18권1호
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• pp.133-142
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• 1993

본 논문은 2차원 물체의 형상 매칭에 관한것으로 다각근사화된 단순 2차원 물체에 적용하였다. 많은 형상 매칭 방법론이 수학적 벡터의 의현에 기초를 두고 확솔적인 패턴 인식을 사용하고 있다. 유출된 형상의 다양성과 많은 데이타량은 형상의 전체적인 구조의 관계를 나타내는데 단점을 갖고 있다. 본 논문에서는 영상을 다 각근사적 과정를 통하여 Relaxation 라벨링 기술을 이용함으로써 형상 매칭의 지점을 해결하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.533-538
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• 2001

In general, shape optimization design of the flow system has done to obtain the effects, which are required in the engineering fields. Most of these designs are accomplished by empirical or numerical analysis. But, in empirical analysis case, it is difficult to obtain an optimal shape in the feasible design region. And, in numerical method case, it usually needs many design parameters, because of the required object-function. In this paper, we present a newly numerical analysis, the growth-strain method having only one design parameter. That optimizes a shape by distributing a design parameter such as dissipation energy to be uniformed in the flow system. Also, we apply this shape design process to the three-flow systems, and then we identify that the resulting shape approaches the known optimal shape in the numerical values. Consequently, we confirm that the proposed method is very efficient and practical in the shape optimization of the flow system.

• 한국정밀공학회지
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• 제26권11호
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• pp.124-130
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• 2009

In the multi-stage shape drawing process, the most important aspect for the economy is the correct design of the various drawing stage. For most of the products commonly available round or square materials can be used as initial material. However, special products should be pre-rolled. This study proposes a process design method of multi-stage shape drawing process for producing cross roller guide. Firstly, a standard classification of shape drawing process is suggested based on the requirement of pre-rolling process. And a design method is proposed to design the intermediate die shape. The process design method is applied to design the multi-stage shape drawing process for producing cross roller guide. Finally, the effectiveness of the proposed design method is verified by FE-analysis and shape drawing experiment.

• 소성∙가공
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• 제18권4호
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• pp.283-289
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• 2009

The multi-stage shape drawing is used to obtain long shaped products with high levels of dimensional accuracy and quality. It is important to design the cross sectional shapes of the intermediate passes to meet the required dimensional accuracy of the final product in the multi-stage shape drawing. Until now, the cross sectional shapes of the intermediate passes have been designed by the experiences. It is still remained unsolved problem to design the cross sectional shapes of intermediate pass drawing dies in the multi-pass shape drawing. In this study, a new technique is proposed to design the cross sectional shapes of intermediate passes. The proposed method is applied to a multi-stage shape drawing for a LM-guide which is one of the representative shape drawing products. In order to verify the effectiveness of the proposed method, FE-simulation and experiments have been carried out. The dimensional accuracy of the proposed method is compared with that of the conventional shape drawing process designed by the industrial engineers.

• 응용통계연구
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• 제23권2호
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• pp.317-323
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• 2010

Measures are very useful tools for comparing the shape variability in statistical shape analysis. For examples, the Procrustes statistic(PS) is isolated measure, and the mean Procrustes statistic(MPS) and the root mean square measure(RMS) are overall measures. But these measures are very subjective, complicated and moreover these measures are not statistical for comparing the shape variability. Therefore we need to study some tests. It is well known that the Hotelling's $T^2$ test is used for testing shape variability of two independent samples. And for testing shape variabilities of several independent samples, instead of the Hotelling's $T^2$ test, one way analysis of variance(ANOVA) can be applied. In fact, this one way ANOVA is based on the balanced samples of equal size which is called as BANOVA. However, If we have unbalanced samples with unequal size, we can not use BANOVA. Therefore we propose the unbalanced analysis of variance(UNBANOVA) for testing shape variabilities of several independent samples of unequal size.