• Proceedings of the KWS Conference
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• 2002.10a
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• pp.314-319
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• 2002

The Automation and Control Group at the University of Brasilia is developing an automatic welding station based on an industrial robot and a controllable welding machine. Several techniques were applied in order to improve the quality of the welding joints. This paper deals with the implementation of a laser-based computer vision system to guide the robotic manipulator during the welding process. Currently the robot is taught to follow a prescribed trajectory which is recorded a repeated over and over relying on the repeatability specification from the robot manufacturer. The objective of the computer vision system is monitoring the actual trajectory followed by the welding torch and to evaluate deviations from the desired trajectory. The position errors then being transfer to a control algorithm in order to actuate the robotic manipulator and cancel the trajectory errors. The computer vision systems consists of a CCD camera attached to the welding torch, a laser emitting diode circuit, a PC computer-based frame grabber card, and a computer vision algorithm. The laser circuit establishes a sharp luminous reference line which images are captured through the video camera. The raw image data is then digitized and stored in the frame grabber card for further processing using specifically written algorithms. These image-processing algorithms give the actual welding path, the relative position between the pieces and the required corrections. Two case studies are considered: the first is the joining of two flat metal pieces; and the second is concerned with joining a cylindrical-shape piece to a flat surface. An implementation of this computer vision system using parallel computer processing is being studied.

• Transactions of Materials Processing
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• v.28 no.6
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• pp.368-374
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• 2019

The past recent years have seen an increasing use of high-strength steel sheets in the automotive industry. However, the formability and damage prediction of these materials requires accurate acquisition of necking and fracture strains. Digital image correlation (DIC) is used to accurately capture the necking and fracture strains during testing. The fact that single time points of capturing vary with frame rate makes the need for an investigation necessary. For the high-strength steel DP980, the frame-rate dependences of the final necking and fracture strains values are analyzed here. To eliminate the influence of gauge length, the strains were measured locally by DIC. Results for three specimen shapes obtained with frame rates of 1 and 900 fps (frames per second) were considered and based on them, triaxiality failure diagrams (TFD) are established. It was observed that after diffuse necking, the deformation path departed from the initially linear one, and the stress triaxiality grew with ongoing deformation. It was further revealed that the frame rate-dependence of the necking strain was rather low (< 2%), whereas the fracture strain could be underestimated by up to 8% when the lower frame rate of 1 fps was used (compared with 900 fps). In this study, this issue is investigated while taking into consideration the three different triaxialities. These results demonstrate the importance of choosing an appropriate frame rate for the determination of necking and fracture strains in particular.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.25-30
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• 2003

Recently, development of digital technology is occupying a large part of multimedia information like character, voice, image, video, etc. Research about video indexing and retrieval progresses especially in research relative to video. In this paper, we propose new algorithm(Frame Feature Comparison) for MPEG video segmentation. Shot, Scene Change detection is basic and important works that segment it in MPEG video sequence. Generally, the segmentation algorithm that uses much has defect that occurs an error detection according to a flash of camera, movement of camera and fast movement of an object, because of comparing former frames with present frames. Therefore, we distinguish a scene change one more time using a scene change point detected in the conventional algorithm through comparing its mean value with abutted frames. In the result, we could detect more corrective scene change than the conventional algorithm.

• Journal of IKEEE
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• v.15 no.2
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• pp.122-128
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• 2011

Although conventional analog linescan cameras are used widely, high-speed, high-resolution Cameralink standard will lead the area of frame grabber industry such as factory automation. In this paper, we are developing embedded frame grabber testbed without PC which will give an another solution to image processing applications. Therefore, we designed hardware schematics and programmed FPGA device with VHDL in order to interface Cameralink standard linescan CCD camera. In the future, our embedded on-chip controller could be applied to various image processing systems such as medical imaging, especially optical coherence tomography, machine vision and industrial electronics.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.350-359
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• 2017

This paper presents a new holistic development approach for the carbon continuous-fiber composite frame of an automotive sunroof assembly. The original steel frame has been designed to get higher bending stiffness with its corrugated cross-sectional shape. The new approach uses the prepregs of a fast cure epoxy and PCM manufacturing processing. For higher productivity, the new frames feature a very simple plat cross sectional shape but achieve high bending stiffness through the laminate design. The sandwich structure with a PET foam core was presented. The frames were made of carbon UD laminae covered single carbon fabric on the outer surfaces. The fabrics provide torsional stiffness and also hold the carbon UD fibers floating in the low viscous epoxy resin of prepregs at the curing temperature during processing. The final product yields approximately 18 % savings in weight compared with the original.

• Journal of the Korea Computer Industry Society
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• v.3 no.9
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• pp.1177-1188
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• 2002

To classify real time Lead pin images in this paper, The image acquisition system was composed to C.C.D, image frame grabber(DT3153), P.C(PentiumIII). I proposed image processing algorithms. This algorithms were composed to real time monitoring, Lead Pin image acquisition, image noise deletion, object area detection, point detection and pattern classification algorithm. The raw images were acquired from Lead pin images using the system. The result images were obtained from raw images by image processing algorithms. In implemental result, The right recognition was 97 of 100 acceptable products, 95 of 100 defective products. The recognition rate was 96% for total 200 Lead Pins.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.880-881
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• 2016

디지털액자가 고전적 액자의 향취를 주며 또한 사진을 바꿀 수 있는 기능도 제공하지만 아직 새 흐름이 되는 못했다. 그 이유는 비싼 가격과 사진을 전송하기가 불편하기 때문이다. 우리는 디지털 액자로 사진 전송을 쉽게 하고, 거기에 더하여 위젯과 보안 기능을 추가하는 연구를 하였다. 사진 전송을 위하여 AWS(Amazon Web Service) 서버를 사용하는데 AWS 서버는 언제 어디서나 원할 때면 사진을 WiFi로 전송할 수 있게 한다. 이는 현재 사용하는 USB나 SD 카드를 이용하여 디지털 사진을 전송하는 것보다 훨씬 편리하다. 우리의 디지털 액자를 사용하면 다른 사람과 사진 교환이 쉽고 따라서 가족, 친구, 동료 사이의 친밀감도 쉽게 높일 수 있다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.4
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• pp.347-353
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• 2000

The construction and ability of CAE program are presented. The merit and ability of MATLAB which is widely using in the field of recently engineering and natural science are also introduced. Also, analysis program of frame structure used the MATLAB language which is divide in 4th generation language is presented. In this paper, the proposed program using MATLB language to be based upon the composition of general CAE program is composed to preprocess, solver and post-process procedure. And it is able to carried out the static and eigenvalue analysis of truss structure and two dimensional frame structure. Also, for the sample pre-processing and post-processing, it is used the characteristic of input window and plot window to be made of the various GUI function. Each finite elements to be required for analysis is formulated by the Galerkin's method, as a kind of weighted residual method. For check of the results of calculation for program used in this paper, the results to be calculated using program to be developed by the author was compared with its of ANSYS code for general structural analysis about two dimensional truss and frame structure.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.1
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• pp.1-5
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• 2007

In this paper, we propose an unmanned patient monitoring system design and performance of a motion capture and sound detection. Unmanned patient monitoring system can be used in the greek koma and meaning deep sleep patient to need 24 hour surveillance. To monitoring, we used laptop, CCTV camera (or PC camera), A/D converter, microphone and detection program. The detection program based on the frame difference method and sound level meter. It had several functions such as data collecting and storing. All of this system was tested in several the simulations of emergency situations. It can be expected that an unmanned patient monitoring system can be used in emergency situation and patient care.

• Korean Journal of Computational Design and Engineering
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• v.12 no.4
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• pp.308-320
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• 2007

A multi-agent and web based engineering framework concerning the automation of fatigue durability analysis for welded bogie frame of railway vehicles is presented. Mostly, this kind of design or analysis includes complex workflow, huge amounts of information processing, and problem solving. Macro programs of I-DEAS, APDL of ANSYS, and in-house fatigue code are utilized for parametric geometry representation, automatic mesh generation, static stress analysis, fatigue durability analysis, post-processing, and data sorting. The engineering framework is implemented on the JADE. Since every task requires a fairly complex process and specialized knowledge, the multi-agent based framework is very useful to keep the independency among several disciplines or tasks and to use distributed hardware and software resources. All engineering programs are integrated by XML wrapper. Related database of the engineering framework and web based user interfaces are also developed. A parametric study is carried out to take into account the effect of geometrical change of transom support bracket on its cumulative fatigue damage. The developed engineering framework reduced remarkably the time and costs required in designing and solving engineering problems.