• Title/Summary/Keyword: Unconstrained

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Total Ankle Replacement (족근관절 전치환술)

  • Park, I.H.;Lee, K.B.;Song, K.W.;Lee, J.Y.;Lee, E.J.;Lee, S.Y.
    • Journal of Korean Foot and Ankle Society
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    • v.1 no.2
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    • pp.89-94
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    • 1997
  • The functional disabilities post arthrodesis of the ankle include difficulty in climbing inclined surface, such as hill, ramps, or stair even through without pain. There will be periankle joints arthrosis as time passes. Total ankle replacement permits remobilization, no need for prolonged immobilization. There will be no increas in the mechanical stress of the neiboring joint. Total ankle replacement has been proposed as an alternative to arthrodesis in the management of painful arthrosis of the tibiotalar joint recently. We performed 7 cases of replacement from 1990. 4. 1 to 1996. 7. 1 with 2-3 years follow up. A retrospective review was undertaken for 7 patients with the arthrosis of tibiotatar joint. The results were as following. 1. The clinical results according to the point system for ankle study evaluation were excellent in 2 cases, good in 4 cases, and fair 1 case. 2. The improvement was especially obvious in terms of pain and functional recovery. 3. Total ankle replacement especially unconstrained type seems quite good alternative to arthrodesis.

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An Effect of Process Parameters on the Generation of Sheet Metal Curvatures in the Incremental Roll Forming Process (점진적 롤 성형 공정에서 공정 변수가 박판 금속의 곡률 생성에 미치는 영향)

  • 윤석준;양동열
    • Transactions of Materials Processing
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    • v.13 no.2
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    • pp.122-128
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    • 2004
  • In order to make a doubly-curved sheet metal effectively, a sheet metal forming process has been developed by adopting the flexibility of the incremental forming process and the principle of bending deformation which causes slight deformation in thickness. The developed process is an unconstrained forming process with no holder. For this study, the experimental equipment is set up with the roll set which consists of two pairs of support rolls and one center roll. In the experiments using aluminum sheets, it is found that the curvature of the formed sheet metal is determined by controlling the distance between supporting rolls in pairs and the forming depth of the center roll and it also depends on the thickness of the sheet metal. In order to check the effect of process parameters on the generation of sheet metal curvatures in this process, the orthogonal array is adopted. From the experimental results, among the process parameters, the distance between supporting rolls in pairs along the direction of one principal radius of curvature as well as the forming depth and the thickness of the material is shown to influence the generation of curvature in the same direction significantly. That is, the other distance between supporting rolls in pairs which are not located in the same direction of one principal radius of curvature, does not have an significant effect on the generation of the curvature in that direction. It mainly affects the generation of curvature in its own direction with the forming depth and the thickness of the material.

Analysis of Process Parameters in the Incremental Roll Forming Process for the Application to Doubly Curved Ship Hull Plate (점진적 롤 성형 공정의 선박 곡가공 적용을 위한 공정 변수 분석)

  • Shim D. S.;Yoon S. J.;Lee S. R.;Seong D. Y.;Han Y. S.;Han M. S.;Yang D. Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2005.10a
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    • pp.322-325
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    • 2005
  • In order to make a doubly-cowed sheet metal effectively, the sheet metal forming process has been developed by adopting the flexibility of the incremental forming process and the principle of bending deformation which causes slight deformation in thickness. The developed process is an unconstrained forming process without holder. The experimental equipment has been set up with the roll set which consists of two pairs of support rolls and one center roll. In order to analyze process parameters in the incremental roll forming process for the application to doubly curved ship hull plate, the orthogonal array is adopted. From the FEM results, among the process parameters, the distance between supporting rolls in pairs along the direction of one principal radius of curvature as well as the forming depth is shown to influence the generation of curvature in the same direction significantly. That is, the other distance between supporting rolls in pairs which are not located in the same direction of one principal radius of curvature, does not have an significant effect on the generation of the curvature in that direction. Also, the forming load and torque from the FEM simulation are acceptable to the system development of the incremental roll forming process for the forming of ship hull plate.

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An Effect of Process Parameters on the Generation of Sheet Metal Curvatures in the Incremental Roll Forming Process (점진적 롤 성형 공정에서 공정 변수가 박판 금속의 곡률 생성에 미치는 영향)

  • Yoon S. J.;Yang D. Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.08a
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    • pp.53-57
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    • 2003
  • In order to make a doubly curved sheet metal effectively, a sheet metal farming process has been developed by adopting the flexibility of the incremental forming process and the principle of bending deformation which causes slight deformation to thickness. The developed process is an unconstrained forming process with no holder. For this study, the experimental equipment is set up with the roll set which consists of two pairs of support rolls and one center roll. In the experiments using aluminum sheets, it is found that the curvature of the formed sheet metal is determined by controlling the distance between supporting rolls in pairs and the forming depth of the center roll and it also depends on the thickness of the sheet metal. In order to check the effect of process parameters on the generation of sheet metal curvatures in this process, the orthogonal array is adopted. From the experimental results, among the process parameters, the distance between supporting rolls in pairs along the same direction of one principle radius of curvature as well as the forming depth and the thickness of the material is shown to influence the generation of curvature in the same direction significantly. That is, the other distance between supporting rolls in pairs which are not located in the same direction of one principle radius of curvature, does not have an significant effect on the generation of the curvature in that direction. It just affects the generation of curvature in its own direction mainly with the forming depth and the thickness of the material.

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Real-time Monitoring System for Rotating Machinery with IoT-based Cloud Platform (회전기계류 상태 실시간 진단을 위한 IoT 기반 클라우드 플랫폼 개발)

  • Jeong, Haedong;Kim, Suhyun;Woo, Sunhee;Kim, Songhyun;Lee, Seungchul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.6
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    • pp.517-524
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    • 2017
  • The objective of this research is to improve the efficiency of data collection from many machine components on smart factory floors using IoT(Internet of things) techniques and cloud platform, and to make it easy to update outdated diagnostic schemes through online deployment methods from cloud resources. The short-term analysis is implemented by a micro-controller, and it includes machine-learning algorithms for inferring snapshot information of the machine components. For long-term analysis, time-series and high-dimension data are used for root cause analysis by combining a cloud platform and multivariate analysis techniques. The diagnostic results are visualized in a web-based display dashboard for an unconstrained user access. The implementation is demonstrated to identify its performance in data acquisition and analysis for rotating machinery.

A Divice of Development and A Social Dominant Factor of the Private Security (민간경비의 사회적 성장요인과 발전방안)

  • Gong, Bae-Wan
    • Journal of the Society of Disaster Information
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    • v.1 no.1
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    • pp.27-42
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    • 2005
  • Recently the demand for civil security and security guards shows rapid growth. However the supply and training system have some limitations. Educational and training systems for civil body and security guards are in the basic level and private organizations trained the professional work force. So this paper is showing what a social dominant factor and a divice of development of the private security. Capitalism is based on a material desire of the human being. the social control of capital value and the management of capital ability reflects the actual condition of the capitalism well. The unconstrained growing and the expansion of capitalism, it finally lost social meaning and an importance of human being element and the safety of the civilian life, began to threat the security of citizen by forming over the material center structure of society. Improving human life quality and material richness on their life leads positive factor of capitalism whereas is causing several crimes through the society which is being threatened around a human being life for a negative factor of the capitalism. Therefore capitalistic social system has offered both a positive factor 'growing' and 'richness' and that of a negative 'structural poverty' and 'lack of security' and they have been remaining the assignment of capitalism 'poverty' and 'security' by settlement in the society for a extremely phenomenon of both sides. In Korea because their recognition of the study approach and the social safety for social security control function is still staying first step and our daily life is annoying from various threat of the society. many studies and the realistic necessity of experience related with social security is being studied. In addition. The development possibility of the civil guard and defense at the civil field which will be keep the social security has a wide position but its study approach and realistic comprehension is still in insufficient condition.

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A Study on comnon-mode-driven shield for capacitive coupling active electrode (용량성 결합 능동 전극의 공통 모드 구동 차폐)

  • Lim, Yong-Gyu
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.4
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    • pp.201-206
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    • 2012
  • The indirect-contact ECG measurement is a newly developed method for unconstrained and nonconscious measurement in daily life. This study introduced a new method of electrode circuit design developed for reducing the 60Hz power line noise observed at the indirect-contact ECG measurement. By the introduced common-mode-driven shielding, the voltage of the electrical shield surrounding the capacitive coupling electrode is maintained at the same as the common mode voltage. Though the method cannot reduce the level of common mode voltage itself, that reduces effectively the differential mode noise converted from the common mode voltage by the difference of cloth impedance between the two capacitive coupling electrode. The experiment results using the actual indirect-contact ECG showed that the 60Hz power line noise was reduced remarkably though the reduction ratio was smaller than the expected by the theory. Especially, the reduction ratio became large for the large difference of cloth. It is expected that the introduced method is useful for reducing the power line noise under condition of poor electrical grounding.

Application of Optimum Design Technique in Determining the Coefficient of Consolidation Using Piezocone Test (피에조 콘 시험을 이용정회원, 한국과학기술원 토목공학과 부교수, 정회원, 한국과학기술원 토목공학과 박사 후 과정한 망일계수 결정시 최적화 기법의 적용)

  • Kim, Yeong-Sang;Lee, Seung-Rae;Kim, Yun-Tae
    • Geotechnical Engineering
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    • v.13 no.4
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    • pp.95-108
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    • 1997
  • For normally consolidated clay, several researchers have developed a number of theoretical time factors to determine the coefficient of consolidation However, depending on the assumptions and analytical techniques, it could considerably vary even for a specific degree of consolidation. In this paper, a method is proposed to determine a consistent coefficient of consolidation over all ranges of degree of consolidation by applying the concept of the Optimum Design Technique. The initial excess pore pressure distribution is assumed to be obtainable by the successive spherical cavity expansion theory. The dissipation of pore pressure is simulated by means of two dimensional linear-uncoupled axisymmetric consolidation analysis. The minimization of the differences between the measured and the predicted excess pore pressures was carried by BFGS unconstrained optimum design algorithm with one dimensional golden section search technique. By analyzing numerical and real field examples, it can be found that the adopted optimum technique gives a consistent and convergent results.

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The automated optimum design of steel truss structures (철골 트러스 구조의 자동화 최적설계)

  • Pyeon, Hae-Wan;Kim, Yong-Joo;Kim, Soo-Won;Kang, Moon-Myung
    • Journal of Korean Association for Spatial Structures
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    • v.1 no.1 s.1
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    • pp.143-155
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    • 2001
  • Generally, truss design has been determined by the designer's experience and intuition. But if we perform the most economical structural design we must consider not only cross-sections of members but also configurations(howe, warren and pratt types etc.) of single truss as the number of panel and truss height. The purpose of this study is to develope automated optimum design techniques for steel truss structures considering cross-sections of members and shape of trusses simultaneously. As the results, it could be possible to find easily the optimum solutions subject to design conditions at the preliminary structural design stage of the steel truss structures. In this study, the objective function is expressed as the whole member weight of trusses, and the applied constraints are as stresses, slenderness ratio, local buckling, deflection, member cross-sectional dimensions and truss height etc. The automated optimum design algorithm of this study is divided into three-level procedures. The first level on member cross-sectional optimization is performed by the sequential unconstrained minimization technique(SUMT) using dynamic programming method. And the second level about truss height optimization is applied for obtaining the optimum truss height by three-equal interval search method. The last level of optimization is applied for obtaining the optimum panel number of truss by integer programming method. The algorithm of multi-level optimization programming technique proposed in this study is more helpful for the economical design of plane trusses as well as space trusses.

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Case Study of Video Work Connecting with Fans : the TV series Making Full Use of Convention (팬과 소통하는 영상작품의 사례 연구 : 컨벤션(convention)을 적극적으로 이용하는 TV 시리즈 <수퍼내추럴(Supernatural)>)

  • Nam, Myoung Hee;You, Eun-Soon
    • Journal of Digital Contents Society
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    • v.16 no.1
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    • pp.145-155
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    • 2015
  • Into the 1990s, there have been changes in perception of pop culture consumers by making a distinction between groups that are active, critical and creative. This study aims to establish a theoretical reasoning for conventions organized and participated voluntarily by fans, which has been especially noticeable in the American subculture for a long time, while investigating how fans and all the parties concerned interact at conventions then to expand the imaginary world. To this end, an analysis has been carried out on the conventions for the particular American TV series of Supernatural. The results show that the reason for this drama series maintaining such enduring vitality as if a living thing is attributable to the special bond of sympathy developed between fans and actors and the following interactions between them. Furthermore, in the aspect of cultural sociology, a piece of work can only be completed through unconstrained interpretation of the work and the resultant recreation by the creator and the receiver, which has been ascertained by this study.