• 한국의상디자인학회지
• /
• 제11권2호
• /
• pp.43-53
• /
• 2009

The purpose of this study is to show inherent and differentiated beauty by designing costume knitwear using Dancho patterns representing peculiar beauty, thus expressing free and convenient knitwear in the modern sense for women with the image of reasonableness and elegance, proposing knit design using high-class materials for satisfying the demand for the highest. With regard to expression technique of works, I selected computer Jacquard method to indicate effective comparison effect of expression material and made expression with $12{\sim}14$ gauge as base by using computer knitting machine. Through above-mentioned research process and design using Knit CAD system, I obtained following conclusion. First, it is possible to express variously and widely traditional patterns by making the most of the beauty of the orient and by recomposing the patterns of plant patterns representing "feminine image". Second, it is possible to widely represent the sense you can feel from knit by expressing variously diversity of knit structure and Jacquard knitting structure and gauge. Finally, it is possible to express designs more freely and imaginably by using computer Knit CAD system instead of actual knitting of various knit expression technique and materials application.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집C
• /
• pp.140-145
• /
• 2001

Lasting machines for shoe manufacturing are continuously developed with the aid of automation and Computer Aided Manufacturing (CAM). Adaptive lasting machine and CAD data of a shoe last are inevitably introduced for the labor-free manufacturing process. Recently, method for the CAD datarization of a shoe last is suggested using finite element mesh system. Initial set up data and control data of machine parts are required for the adaptive lasting machine. For the efficient process, grading of those data is essential to minimize data storage and production costs. In this paper, bonding lines are extracted from the CAD data of a shoe last and graded by the geometric grading system. Tension spline method is adopted for the interpolation of last CAD data. The results are compared with the results from the arithmetic grading system that is widely adopted in the shoemaking companies.

• 전자공학회논문지B
• /
• 제30B권1호
• /
• pp.10-17
• /
• 1993

This paper analyzes succinct graph descriptions and its complexity of connectivity problems on context free graph languages under various restrictions. It defines SNLC(Simple Context Free Node Label Controlled) grammar and presents reduction method that solves graph problems without expanding the hierarchical description. It exemplifies the method by giving efficient solutions to connectivity problems on graphs and presents parallel algorithm for reduction and analyzes the complexity. Its results will help application of desing for NETWORK. CAD. VLSI and other engineering problems.

• 한국CDE학회지
• /
• 제21권2호
• /
• pp.65-68
• /
• 2015

Creative selfie stick design using FreeCAD and Ansys.

• 한국건축시공학회지
• /
• 제22권2호
• /
• pp.183-194
• /
• 2022

본 연구는 BF인증 평가방식의 BIM기반 검토 효율성 제고를 위한 기초연구로서 BIM 전문가를 대상으로 설문조사를 실시하였다. 건축물의 용도를 초등학교로 제한하여 BF인증 평가항목의 의무시설을 평가기준에 맞게 도출하는 것으로 예비조사를 실시하여 총 94개의 평가항목 중 63개 항목이 도출되었다. 도출된 시설은 매개시설, 내부시설, 위생시설이었으며 1차 조사는 BF인증 평가항목의 세부산출기준을 제공하고 BIM기반의 검토 가능성을 조사한 결과 31개의 항목이 도출되었다. 마지막 2차 조사에서 현행 CAD기반의 평가방식과 BIM기반의 평가방식의 효율성 정도를 물어 도출된 평가항목 중 96.8%가 BIM기반의 평가방식이 더 효율적임을 나타내었고, CAD기반의 평가방식은 단 1개의 평가항목인 3.2%를 나타내었다.

• 한국CDE학회지
• /
• 제21권2호
• /
• pp.61-64
• /
• 2015

In this paper, the FREECAD 0.14 was used for modeling conventional Selfie-stick and the newly proposed Selfie-stick design. The purpose of this paper is to demonstrate the utility of FREECAD 0.14, which is open-source and still in development for further use. After modeling the conventional Selfie-stick, CatiyaV5 was used to assemble FREECAD 0.14 drawn elements. Main issue in newly designed Selfie-stick is the portability. To improve portability of the Selfie-stick, folding mechanism was adopted from folding LED stands. Several mechanisms were adopted to improve user convenience as well. Ansys 14.0 was used for structural analyses of conventional Selfie-stick model and the newly designed model as well. Several simplifications for the models were needed to process the analyses. When analyzing the newly designed model various materials were used one by one to find compatible composition. Using Magnesium Alloy for the stick and the hand grip was found to be compatible. FREECAD was useful for suggestion of the newly designed model but not so much useful to design an actual product. Various efforts would make FreeCAD the best choice for industrial use for free as it is named.

• International Journal of CAD/CAM
• /
• 제8권1호
• /
• pp.1-10
• /
• 2009

This paper presents a topology optimization approach using element-free Galerkin method (EFGM) for the optimal design of compliant mechanisms with geometrically non-linearity. Meshless method has an advantage over the finite element method(FEM) because it is more capable of handling large deformation resulted from geometrical nonlinearity. Therefore, in this paper, EFGM is employed to discretize the governing equations and the bulk density field. The sensitivity analysis of the optimization problem is performed by incorporating the adjoint approach with the meshless method. The Lagrange multipliers method adjusted for imposition of both the concentrated and continuous essential boundary conditions in the EFGM is proposed in details. The optimization mathematical formulation is developed to convert the multi-criteria problem to an equivalent single-objective problem. The popularly applied interpolation scheme, solid isotropic material with penalization (SIMP), is used to indicate the dependence of material property upon on pseudo densities discretized to the integration points. A well studied numerical example has been applied to demonstrate the proposed approach works very well and the non-linear EFGM can obtain the better topologies than the linear EFGM to design large-displacement compliant mechanisms.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
• /
• pp.249-254
• /
• 1987

This paper presents a new method for generating smooth free-form surface by local correction. B-spline surface is used for its convenience of local correction, and the direction of surface correction is fixed to the average-surface-normal direction. The surface to be corrected is approximated into a uniform cubic B-spline surface. Then, the smoothness (curvature arrows, iso-parametric lines) of the approximated surface is displayed with B-spline control points. When a control point near the region that needs correction is selected, a new point 1 mm higher than the original control point in the direction of the average surface normal is displayed. And the surface is corrected by giving the amount of control point movement interactively. Since the direction of correction is given by the program and the amount of correction is selected by the user, the method is called semiautomatic. sufficiently smooth surface can be obtained by this method. Examples are given to illustrate the method.

• Journal of Biosystems Engineering
• /
• 제16권3호
• /
• pp.228-238
• /
• 1991

Cam plays very important roles due to continuous requirement for the high-speed and automation of the machinery. A large number of studies of cam curve were carried out by many researchers, and CNC milling and machining center for manufacturing cam have been widely used recently. The purpose of this study was to develop a CAD/CAM system for cam using QuickBasic language in 16-bit PC for application of cam design and manufacturing. Results obtained were as follows : 1. It was possible to input data by entering cam angle and its corresponding R, from 0 to 360 deg. of cam angle. The tediousness at entering data was minimized because of the same data format for both cylindrical cam and disc cam, and free format used for data file. 2. It was possible to design cam by choosing only the number of cam curve because of developing the CAD/CAM program with dimensionless method of cam curves including widely used 19 kinds. After selecting the number of the cam curve, the CAD/CAM system automatically shows the characteristics of cam motion enough to help a designer to decide : displacement, velocity, acceleration and jerk. 3. It was possible to execute, in an efficient way, both the cam profile synthesis and the generation of NC program for CNC machining center by using the input data. 4. This NC program generated by the CAD/CAM system developed here, was evaluated as positive in relation with actual manufacturing experiments and thought to be useful in its application without any modification. It can be said that this CAD/CAM system could be used by the beginners to design and manufacture the cam automatically as the system consists of very simple dialogue methods. In addition, self-developed QuickBasic would be would used as a basic tool for further stuides in this area of research, together with application.

• 소성∙가공
• /
• 제13권7호
• /
• pp.614-622
• /
• 2004

A new approach for the automatic elimination of free edges in the finite element model for the analysis of sheet metal forming processes is presented. In general, the raw finite element model constructed from an automatic mesh generator is not well suited for the direct use in the downstream forming analysis due to the many free edges which requires tedious time consuming interactive graphic operations of the users. In the present study, a general method for the automatic elimination of free edges is proposed by introducing a CAD/CAE hybrid method. In the method a trimmed parametric surface is generated to fill the holes which are orginated from the free edges by using the one step elastic finite element analysis. In addition, mesh generation algorithm is suggested which can be used in the general trimmed surface. In order to verify the validity of the proposed method, various examples including actual automobile sheet metal parts are given and discussed.