• 제목/요약/키워드: Convergence time

검색결과 7,156건 처리시간 0.032초

정적-외연적 강소성 유한요소법의 개발 및 Osakada방법에서 변형율 증분에 따른 영향분석 (Development of Static-explicit rigid-plastic finite Element Method and Investigate the offset of strain increment in Osakada method)

  • 정동원;이승훈
    • 한국정밀공학회지
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    • 제21권2호
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    • pp.116-121
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    • 2004
  • In rigid-plastic finite element method, there is a heavy computation time and convergence problem. In this study, static-explicit rigid-plastic finite element method will be introduced. This method is the way that restrict the convergence interval. It is expected that various results from the numerical analysis will give very useful information for the design of tools in sheet metal forming process.

포토 센서를 이용한 브라운관의 컨버젼스 측정 성능 향상에 관한 연구 (A study on improvement of convergent measurement performance of color display tube using photo sensors)

  • 송원경;박종철
    • 전자공학회논문지S
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    • 제35S권3호
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    • pp.93-101
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    • 1998
  • In Integrated Tube Components(ITC) process in themanufacturing of color display tube, we describe the necessity of the convergence measurement method using photo sensors. Compared with methods using 1D or 2D cameras, its characteristics is to use of moving image patterns and fixed sensors. This measurement method is formulated as the measurement problem of the phase difference in phase changing periodic signals. The convergence measurement system using photo sensors, for the good performance, must have a small standard deviation for the repetitive measurement in the same condition and a fast measurement time for thecovergence change. By above two conditions, we proposed the real time measurement algorithm of the pahse difference using fundametal and harmonic in phase changing periodic signals. And, the proposed algorithm is applied to the convergence measurement system.

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제한 Filtered-x LMS 알고리즘을 이용한 능동 소음제어 (Active Noise Control using Constrained Filtered-x LMS Algorithm)

  • 나희승;박영진
    • 소음진동
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    • 제8권3호
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    • pp.485-493
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    • 1998
  • Many of the adaptive noise control systems utilize a form of the least mean square (LMS) algorithms. In the active control of noise, it is common practice to locate an error microphone far from the control source to avoid the near-field effects by evanescent waves. Such a distance between the control source and the error microphone makes a certain level of time-delay inevitable and, hence, may yield undesirable effects on the convergence properties of control algorithms such as filtered-x LMS. This paper discusses the dependence of the convergence rate on the acoustic error path in these popularalgorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. Performances of the new LMS algorithms are presented in comparison with those by the conventional algorithms based on computer simulations and experiments.

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Real-time Heart Rate Measurement based on Photoplethysmography using Android Smartphone Camera

  • Hoan, Nguyen Viet;Park, Jin-Hyeok;Lee, Suk-Hwan;Kwon, Ki-Ryong
    • 한국멀티미디어학회논문지
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    • 제20권2호
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    • pp.234-243
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    • 2017
  • With the development of smartphone technologies enable photoplethysmogram (PPG) acquisition by camera and heart rate (HR) measurement. This papers presents improved algorithm to extract HR from PPG signal recorded by smartphone camera and to develop real-time PPG signal processing Android application. 400 video samples recorded by Samsung smartphone camera are imported as input data for further processing and evaluating algorithm on MATLAB. An optimized algorithm is developed and tested on Android platform with different kind of Samsung smartphones. To assess algorithm's performance, medical device Beurer BC08 is used as reference. According to related works, accuracy parameters includes 90% number of samples that has relative errors less than 5%, Person correlation (r) more than 0.9, and standard estimated error (SEE) less than 5 beats-per-minutes (bpm).

Comparison of Time Implicit Symmetric Gauss-Seidel Iterative Schemes for Computation of Hypersonic Nonequilibrium Flow

  • Lee, Chang Ho;Park, Seung O
    • International Journal of Aeronautical and Space Sciences
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    • 제2권1호
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    • pp.1-11
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    • 2001
  • The time implicit point SGS scheme is applied to compute hypersonic viscous flows in thermochemical nonequilibrium. The performance of the point SGS scheme is then compared with those of the line SGS and the LU-SGS schemes. Comparison of convergence histories with the effect of multiple forward and backward sweeps are made for the flow over a 2D cylinder experimentally studied by Hornung and the flow over a hemisphere at conditions corresponding to the peak heating condition during the reentry flight of an SSTO vehicle. Results indicate that the point SGS scheme with multiple sweeps is as robust and efficient as the line SGS scheme. For the point SGS and the LU-SGS scheme, the rate of improvement in convergence is largest with two sweep cycles. However, for the line SGS scheme, it is found that more than one sweep cycle deteriorates the convergence rate.

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A Historical Study on the Successful Convergence Research Between Lavoisier and Laplace

  • Jung, Won
    • International Journal of Advanced Culture Technology
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    • 제8권2호
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    • pp.28-33
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    • 2020
  • The Chemist Antoine-Laurent Lavoisier and mathematician Pierre Simon Laplace, who conducted a collaborative research on heat phenomena, are two of the key figures that represent French scientific community in the late 18th century. They joined hands together to understand heat phenomena that had not been fully explained until that time. They studied heat phenomena based on a heat particle model called 'caloric' and this study further expanded into light, magnetism and electricity, laying groundwork for many other research achievements afterwards. This article goes through their individual researches and looks into the process of their joint research based on the analysis of their publications. Further to these, it emphasizes its continuity with the Laplacian Program, a large-scale research project conducted in the early 19th century. Lastly, this article presents how science can merge with history, and at the same time, introduces the prerequisites for successful convergence research through existing research cases.

분할구조 기반의 다기능 연산 유전자 알고리즘 프로세서의 구현 (Implementation of GA Processor with Multiple Operators, Based on Subpopulation Architecture)

  • 조민석;정덕진
    • 대한전기학회논문지:시스템및제어부문D
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    • 제52권5호
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    • pp.295-304
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    • 2003
  • In this paper, we proposed a hardware-oriented Genetic Algorithm Processor(GAP) based on subpopulation architecture for high-performance convergence and reducing computation time. The proposed architecture was applied to enhancing population diversity for correspondence to premature convergence. In addition, the crossover operator selection and linear ranking subpop selection were newly employed for efficient exploration. As stochastic search space selection through linear ranking and suitable genetic operator selection with respect to the convergence state of each subpopulation was used, the elapsed time of searching optimal solution was shortened. In the experiments, the computation speed was increased by over $10\%$ compared to survival-based GA and Modified-tournament GA. Especially, increased by over $20\%$ in the multi-modal function. The proposed Subpop GA processor was implemented on FPGA device APEX EP20K600EBC652-3 of AGENT 2000 design kit.

A Study for analysis of Inverse Kinematics system to Character Animations & Motion Graphics education

  • Cho, Hyung-ik;Shin, Seung-Jung
    • International journal of advanced smart convergence
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    • 제10권3호
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    • pp.149-156
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    • 2021
  • Today, 3D softwares have become an essential tool in all areas of Video, including Movies, Animations, CFs, Motion Graphics and Games. One of the most commonly used fields is the 3D character video part. However, these 3D character animations and motion graphics softwares are difficult to learn and too much to learn, making it difficult to learn them all in a university education with a limited time of four years. In this paper, many Inverse kinematics tools, which are essential in the 3D character animations and motion graphics field, compare and analyze the strengths and weaknesses of each tool, focusing on Bone, Character Studio, and Character Animation Toolkit, which are most commonly used in work fields. And use Delphi techniques for 3D experts to secure objectivity. Therefore, for universities that require large amounts of teaching in a limited time, I propose an analysis of which of the above three Inverse Kinetics tools is advantageous for students to select and focus on for efficient education.

Offset Wrist를 갖는 6자유도 협동로봇의 역기구학 해석 (Inverse Kinematic Analysis of a 6-DOF Collaborative Robot with Offset Wrist)

  • 김기성;김한성
    • 한국산업융합학회 논문집
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    • 제24권6_2호
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    • pp.953-959
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    • 2021
  • In this paper, the numerical inverse kinematics analysis is presented for a collaborative robot with an offset wrist. Robot manipulators with offset wrist are widely used in industrial applications, due to many advantages over those with wrist center and those with three parallel axes such as simple mechanical design, light weight, and so on. There may not exist a closed-form solution for a robot manipulator with offset wrist. A simple numerical method is applied to solve the inverse kinematics with offset wrist. Singularity is analyzed using Jacobian matrix and the numerical inverse kinematics algorithm is implemented on the real-time controller.

안드로이드 환경에서 화면 캡쳐와 OCR을 활용한 실시간 번역 애플리케이션 개발 (Development of a Real-time Translation Application using Screen Capture and OCR in Android Environment)

  • 이승우;김성진;윤영현;백재순
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2023년도 제68차 하계학술대회논문집 31권2호
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    • pp.267-268
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    • 2023
  • 본 논문은 안드로이드에서 화면 캡쳐와 OCR을 통한 실시간 번역 애플리케이션 개발을 주제로 한다. 코틀린으로 개발된 애플리케이션은 사용자가 원하는 화면 영역을 캡쳐하여 해당 텍스트를 OCR로 추출하고, 구글 Cloud Vision API와 Cloud Translation API를 활용해 번역한다. 이를 통해 외국어 애플리케이션 사용의 편의성을 향상시키고, 정보의 이해와 공유를 도울 수 있음을 제시한다. 이 기술은 더욱 다양한 분야에서의 활용 가능성을 열어놓고 있다.

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