• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.27 no.1
• /
• pp.75-82
• /
• 1991

The present paper describes a preliminary design method by using the computer graphics for creation of the fore and after body profiles of fishing vessel. It is well known that the Form Parameter design method has some merits at an early stage of design, and the B-spline curve generation technique has some prior properties in representing hull form with the computer graphic. The B-spline curve generation technique combined with the form parameter design method is employed to generate the profiles of fishing vessel. For fore body the stem profiles with bulbous bulb or without one are considered. And for after body the stern profiles of cruiser type and the transom type are generated with stern bulb or with shoe piece. Several examples will shown.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.4
• /
• pp.729-740
• /
• 1994

In the shape optimal design based on h-version of FEM, the ideal mesh for the initial geometry most probably will not be suitable for the final analysis. Thus, it is necessary to remesh the geometry of the model at each stage of optimization. However, the p-version of FEM appears to be a very attractive alternative for use in shape optimization. The main advantages are as follows; firstly, the elements are not sensitive to distortion for interpolation polynomials of order $p{\geq}3$; secondly, even singular problems can be solved more efficiently with p-version than with the h-version by proper mesh design; thirdly, the initial mesh design are identical. The 2-D p-version model for shape optimization is presented on the basis of Bezier's curve fitting, gradient projection method, and integrals of Legendre polynomials. The numerical results are performed by p-version software RASNA.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 1997.10a
• /
• pp.230-234
• /
• 1997

Reverse engineering involves digitizing a three-dimensional model or part converting the data to a CAD database description and manufacturing by CNC. Currently, the digitization is done through measurements taken manually by a CMM or touch probe mounted on a CNC machinetool. Some reverse engineering techniques require close integration between the data collection method and the surface-fitting algorithms. Accurate surface data are collected by input to the surface fitting method. This study has been found that both the smoothness of surfaces and accuracy of surface fitting are related with the degree of the interpolated surfaces.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2016.06a
• /
• pp.338-339
• /
• 2016

손 제스처는 스마트 글래스 등 웨어러블 기기의 NUI(Natural User Interface)로 부각되고 있으며 이를 위해서는 손 제스처 검출 및 인식 기능이 요구된다. 또한, 최근 MPEG 에서는 IoT(Internet of Thing) 환경에서의 미디어 소비를 위한 표준으로 IoMTW(Media-centric IoT and Wearable) 사전 탐색이 진행되고 있으며, 손 제스처를 표현하기 위한 메타데이터도 하나의 표준 기술요소로 논의되고 있다. 본 논문에서는 스마트 글래스 환경에서의 손 제스처 인식을 위한 과정으로 스테레오 영상을 통한 손 윤곽선 검출과 이를 메타데이터로 서술하기 위하여 베지에(Bezier) 곡선으로 표현하는 기법을 제시한다.

• 유체기계공업학회:학술대회논문집
• /
• 2004.12a
• /
• pp.119-124
• /
• 2004

In this study, a rotor blade of a Curtis turbine is investigated. Bezier curve is generally used to define the profile of turbine blades. However, this curve gives a feature of global control, which is not proper to a supersonic impulse turbine blade. Thus, a blade design method is developed by using B-spline curve so that local control is possible to obtain an optimized blade section. To design a Curtis turbine blade section systematically, the blade section has been changed by varying three design parameters using central composite design method. Flow analyses have been carried out for the blade sections, and the effects of design parameters are evaluated.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2016.11a
• /
• pp.33-35
• /
• 2016

손 제스처는 스마트 글라스 등 웨어러블 기기의 NUI(Natural User Interface)를 구현하기 위한 수단으로 각광받고 있다. 최근 MPEG 에서는 IoT(Internet of Things) 및 웨어러블 환경에서의 미디어 소비를 지원하기 위한 IoMTW(Internet of Media-Things and Wearables) 표준화를 진행하고 있다. 본 논문에서는 손 제스처를 웨어러블 기기의 NUI 로 사용하여 웨어러블 기기 제어 및 미디어 소비를 제어하기 위한 손 제스처 검출과 인식 기법를 제시한다. 제시된 기법은 스테레오 영상으로부터 깊이 정보와 색 정보를 이용하여 손 윤곽선을 검출하여 이를 베지어(Bezier) 곡선으로 표현하고, 표현된 손 윤곽선으로부터 손가락 수 등의 특징을 바탕으로 제스처를 인식한다.

• Journal of Korean Institute of Industrial Engineers
• /
• v.21 no.4
• /
• pp.529-540
• /
• 1995

The paper deals with a procedure for constructing a composite surface interpolating a polygonal curve mesh defined from 3D scattered points. The procedure consists of a poly-angulation, construction of a curve net, and interpolation of the curve net. The poly-angulation contains a stage that changes a triangular edge net obtained from a triangulation into a poly-angular edge net. A curve net is constructed by replacing edges on the edge net with cubic Bezier curves. Finally, inside of an n-sided polygon is interpolated by n subdivided triangular subpatches. The method interpolates given point data with relatively few triangular subpatches. For an n-sided polygon, our method constructs an interpolant with n subdivided triangular subpatches while the existing triangular surface modeling needs 3(n-2) subpatches. The obtained surface is composed of quartic triangular patches which are $G^1$-continuous to adjacent patches.

• Proceedings of the KAIS Fall Conference
• /
• 2001.05a
• /
• pp.273-276
• /
• 2001

본 논문에서는 레이져 마킹용 갈바노미터의 구동을 위하여 마킹에 필요한 벡터 폰트의 개발환경 구축하고, 만들어진 벡터 폰트를 PC와 구동 장치간의 통신용 인터페이스를 제작하여 갈바노미터(galvanometer)에 송신, 출력할 수 있도록 하였다. 벡터 폰트의 곡선 처리는 베지어(Bezier) 함수를 사용한 외곽선 폰트(outline pent)를 사용하였다. 폰트 에디터를 이용하여 문자를 작성한 후 문자의 외곽선 정보를 인터페이스 카드에 보내고, 이 데이터를 D/A 변환기를 통해 갈바노미터 구동장치를 구동하고, 레이져를 갈바노미터 반사경에 조사하여 폰트를 출력할 수 있도록 하였다. 인터페이스 카드는 16비트 D/A변환기를 이용하여 PC의 ISA버스를 이용하였다. 실험을 통해 개발된 장치의 구동이 올바르게 동작함을 확인하였다.

• Proceedings of the KIEE Conference
• /
• 1999.07g
• /
• pp.2895-2897
• /
• 1999

화상을 확대함으로써 생기는 화상 몽롱화 (blurring) 현상과 블럭화 현상을 제거하기 위해 본 논문에서는 방향성을 고려한 B 스플라인 함수를 이용하여 화상을 보간하는 방법을 제시한다. 이 방법은Hermite 3차 스플라인 함수나, Bezier 곡선 함수를 이용한 방법 보다 적은 차수를 가질 수 있으므로 계산 량을 줄일 수 있다 또한 화소를 중심으로 수직, 수평 대각선 방향의 분산값을 구하여 변화가 적은 방향으로 보간을 실행함으로써 블럭화 현상과 몽롱화 현상을 감소시켜 확대 화상을 보간 시킨다.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.6
• /
• pp.137-145
• /
• 2016

A novel tracking method is proposed to find coronary artery using high-order curve model in coronary CTA(Computed Tomography Angiography). The proposed method quickly generates numerous artificial trajectories represented by high-order curves, and each trajectory has its own cost. The only high-ranked trajectories, located in the target structure, are selected depending on their costs, and then an optimal curve as the centerline will be found. After tracking, each optimal curve segment is connected, where optimal curve segments share the same point, to a single curve and it is a piecewise smooth curve. We demonstrated the high-order curve is a proper model for classification of coronary artery. The experimental results on public data set sho that the proposed method is comparable at both accuracy and running time to the state-of-the-art methods.