• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.27-33
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• 1996

In this study, a CAD/CAM system for axisymmetric deep drawing processes has been developed. An approach to the system is based on the knowledge based system. Under the environment of CAD/CAM software of Personal Designer, the system has been written in UPL. The geometries of intermediate and final object in deep drawing process, including processes parameters are input for the CAD/CAM system. The input data can be obtained from the results of Pro_Deep. The parts drawing of die sets for each process is generated in tool design module of the CAD/CAM system. Also. the die assembly drawings can be obtained. NC commands for machining of the part can be generated in the developed CAD/CAM system.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.2
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• pp.71-78
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• 2001

In ship building industry, CNC and CAM are mostly applied to NC cutting and manufacturing of propeller and prototype ship model. Herein, prototype ship model is producted by CAD/CAM process. Hull form data is obtained from the ship drawing and used for 3D modeling by CAD software Pro/Engineer. CAD data is transferred into CAM s/w SPEEDplus to perform CNC process and the prototype small ship model is manufactured by CNC machine. To solve data transfer among different systems. IGES and STEP neutral formats are currently used. Herein IGES format is adopted for data transfer between CAD/CAM softwares.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.766-770
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• 1996

In this study, a CAD/CAM system for axisymmetric deep drawing processes has been developed. An approach to the system is based on the knowledge based system. Under the environment of CAD/CAM software of Personal Designer, the system has been written in UPL. The geometries of intermediate and final object in deep drawing process, including processes parameters are input for the CAD/CAM system. The input data can be obtained from the results of Pro-Deep. The parts drawing of die sets for each process is generatedin tool design module of the CAD/CAM system. Also, the die assemblydrawings can be obtained. NC commands for machining of the part can be generated in the developed CAD/CAM system.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.4
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• pp.30-41
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• 1993

Developed in this paper is a feature based modeling system for the design of welded plat construction(WPC) which is composed of flat or bended plates represented as reference plane with a constant thickness. First, the necessity and the characteristics of the modeing system for WPC as compared with the assembly of mechanical parts are investigated. Secondly, feature library for the assembly of WPC is shown which contains several types of features like joint feature, groove feature, material feature, and precision feature. Thirdly, the assembly procedures are presented which mainly consist of both the assembly transformation and the correct assembly checking. Fourthly, weld lines of the assembled WPC are defined so that those can be used in the process planning or the manufacturing stage. Finally, a prototype by a geometric modeling software Pro/Engineer, a graphic software GL(Graphic Library), and C language on a CAD workstation IRIS.

• Transactions of Materials Processing
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• v.7 no.3
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• pp.246-259
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• 1998

This paper describes a research work of developing a computer-aided design and manufacturing of irregular shaped sheet metal product for blanking or piercing and bending operations. An approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories experimental results and the empirical knowledge of field experts, This system has been written in AutoLISp on the AutoCAD and in customer tool kit on the SmartCAM with a personal computer and is composed of nine modules which are input and shape treatment, flat pattern-layout, pro-processor module. Based on the knowledge-based rules, the system is designed by considering several factors, such as material and thickness of product complexities of blank geometry and punch profile sheet metal to give flat pattern and automatically account for the adjustment of bending allowances to match tooling requirements by checking dimensions and generating NC data automatically according to drawings of die-layout module. Results carried out in each module will provide efficiencies to the designer and the manufacturer of blanking or piercing and bending die in this field.

• Korean Journal of Dental Materials
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• v.44 no.2
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• pp.151-161
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• 2017

The purpose of this study was to examine the effect of shade and thickness of resin-nanoceramic CAD-CAM block (RNB) on the microhardness of dual-cured resin cement, as well as to measure the number of photons transmitted through RNBs of different thicknesses and colors. One dual-cured resin cement was used to prepare resin cement specimens. Resin cement specimens were light-cured for 40 seconds through 3 shades (A1, A2, A3 in HT (high translucency) and LT (low translucency) respectively) and four thicknesses (1, 2, 3, 4 mm) of RNB specimens. Vickers microhardness measurements of resin cement specimens were performed using a Vickers hardness tester. The light transmission of RNB specimens was measured using a spectrometer (SpectroPro-500, Acton Research, Acton, MA, U.S.A.), and the translucency parameter was calculated using the CIEL*a*b* system. Data were statistically analyzed by ANOVA and Tukey's test. There was a significant decrease of microhardness of resin cement specimen with an overlay of 4 mm of RNB thickness and A3 shade in comparison to A1 and 1 mm, respectively (p<0.05). The translucency parameter values and light transmission of RNBs tested differed significantly, according to the thicknesses of the specimen (p<0.05). Light transmission is decreased with increase in the thicknesses of RNBs. Shade A1 transmitted more light than darker blocks. A decrease in microhardness of resin cement specimens was observed with increasing thickness and shade (A1 to A3) of RNBs.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.11a
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• pp.245-248
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• 2007

본 논문에서는 PXA270 임베디드 시스템을 이용한 거동관리 프로그램 개발한다. 개발 프로그램의 목적은 혼자 있는 환자 또는 독거노인의 거동을 관리함으로서 응급상황을 신속히 처리하도록 한다. 우선 개발 프로그램은 웹 카메라(QuickCam Pro5000)를 사용하여 Visual Studio 2005로 기본프로그램을 작성하였다. 웹 카메라로 부터 영상을 받아온 후 기준영상을 등록을 한다. 다음 단계로 감시되고 있는 영상에 사람이 들어오거나 움직이는 물체가 있다면 감시영상에서 기준영상을 뺀 차영상 기법을 이용하여 지속적으로 물체를 추적 한 다음 물체가 일정시간 이상 움직이지 않는다면 경고 메세지를 출력하게 된다. 최종적으로 개발된 알고리즘을 임베디드 시스템인 PXA270에 탑재하기 위하여 Embedded Visual C++ 4.0을 이용하여 증명 한 후, 실험을 통하여 제안방법의 타당성올 검토한다.

• Korean Journal of Computational Design and Engineering
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• v.19 no.4
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• pp.356-367
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• 2014

A robotic sapatial augmented reality (RSAR) system, which combines robotic components with projector-based AR technique, is unique in its ability to expand the user interaction area by dynamically changing the position and orientation of a projector-camera unit (PCU). For a moving PCU mounted on a conventional robotic device, we can compute its extrinsic parameters using a robot kinematics method assuming a link and joint geometry is available. In a RSAR system based on user-created robot (UCR), however, it is difficult to calibrate or measure the geometric configuration, which limits to apply a conventional kinematics method. In this paper, we propose a data-driven kinematics control method for a UCR-based RSAR system. The proposed method utilized a pre-sampled data set of camera calibration acquired at sufficient instances of kinematics configurations in fixed joint domains. Then, the sampled set is compactly represented as a set of B-spline surfaces. The proposed method have merits in two folds. First, it does not require any kinematics model such as a link length or joint orientation. Secondly, the computation is simple since it just evaluates a several polynomials rather than relying on Jacobian computation. We describe the proposed method and demonstrates the results for an experimental RSAR system with a PCU on a simple pan-tilt arm.

• Journal of Broadcast Engineering
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• v.17 no.6
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• pp.945-953
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• 2012

A depth map can be obtained by projecting/capturing patterns of stripes using a projector-camera system and analyzing the geometric relationship between the projected patterns and the captured patterns. This is usually called structured light technique. In this paper, we propose a new multi-threading scheme for accelerating a conventional structured light technique. On CPUs and GPUs, multi-threading can be implemented by using OpenMP and CUDA, respectively. However, the problem is that their performance changes according to the computational conditions of partial processes of a structured light technique. In other words, OpenMP (using multiple CPUs) outperformed CUDA (using multiple GPUs) in partial processes such as pattern decoding and depth estimation. In contrast, CUDA outperformed OpenMP in partial processes such as rectification and pattern segmentation. Therefore, we carefully analyze the computational conditions where each outperforms the other and do use the better one in the related conditions. As a result, the proposed method can estimate a depth map in a speed of over 25 fps on $1280{\times}800$ images.