• 제목/요약/키워드: great freedom

검색결과 107건 처리시간 0.03초

하이퍼텍스트의 개념과 응용에 관한 고찰 (An Overview of Hypertext and Its Applications)

  • 정영미
    • 정보관리학회지
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    • 제6권2호
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    • pp.3-20
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    • 1989
  • 하이퍼텍스트시스템은 비직선적이며 비연속적인 형태로 문헌을 조직하고 이용할 수 있는 새로운 형태의 정보시스템이다. 하이퍼텍스트는 정보뭉치를 소장하는 노드와 상호 관련된 노드들을 연결하는 링크로 구성되며 노드에는 텍스트, 그래프, 그림, 비디오화면, 소리 등의 정보가 소장될 수 있다. 이용자는 링크를 선택함으로써 원하는 정보에 자유롭게 접근할 수 있다. 이 논문에서는 하이퍼텍스트의 개념, 구성요소, 특성 둥을 구체적으로 살펴보고 PC용 상용시스템인 Guide에 관해 간단한 응용 예를 들어 기술하였다.

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SWM을 이용한 케이블 드라이브 시스템 (SWM Utilized Cable Drive System)

  • 이범주;김갑일
    • 전기학회논문지
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    • 제63권2호
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    • pp.272-276
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    • 2014
  • In this paper, cable drive mechanism is proposed to implement high reduction gear ratio. Cable drive mechanism has great advantages such as light weight, high degree of freedom about design aspect and zero backlashes. However, it is restrictively utilized for robotic applications because it is difficult to implement high reduction gear ratio more than 10 to 1. Proposed mechanism enables multi-level reductions by adopting seamless winding method (SWM) which links the previous output axis and the next input axis. Consequently, this reduces the mechanical complexity significantly and enables high reduction with only one single wire cable. 3D CAD design was provided and prototype was manufactured.

A Study of Trajectory Simulation of Master Arm

  • Moon, Jin-Soo
    • 조명전기설비학회논문지
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    • 제22권7호
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    • pp.1-6
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    • 2008
  • In industrial fields, human works are being replaced by robots. However, as the use of robots is limited in the process industry where they are operated fixedly, humanoid robots with wide applications need to be developed. Currently a great deal of research is being conducted on humanoid robots with the object of replacing humans in the workplace. However, because of the lack of relevant hardware and difficulty in mechanical parts, only very simple and limited progress is being made. In an effort to overcome these limitations, the purpose of the present study is to develop a kinematical mechanism and a controller. To this end, master arms with 3 degrees-of-freedom for the shoulders and the arms were composed which were able to reproduce human-like motions by simulating the characteristics of joint variables and the trajectory of the end-effector.

An 8-node assumed strain element with explicit integration for isotropic and laminated composite shells

  • Kim, K.D.;Park, T.H.
    • Structural Engineering and Mechanics
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    • 제13권4호
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    • pp.387-410
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    • 2002
  • Formulation of an 8 nodes assumed strain shell element is presented for the analysis of shells. The stiffness matrix based on the Mindlin-Reissner theory is analytically integrated through the thickness. The element is free of membrane and shear locking behavior by using the assumed strain method such that the element performs very well in modeling of thin shell structures. The material is assumed to be isotropic and laminated composite. The element has six degrees of freedom per node and can model the stiffened plates and shells. A great number of numerical testing carried out for the validation of present 8 node shell element are in good agreement with references.

4개의 자기 부상 액츄에이터 제어에 관한 연구 (A Study on Four Magnetic Levitation Actuator Control)

  • 원진국;문지우;조윤현;구대현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.940-941
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    • 2008
  • Recently, there are a great many research for magnetic levitation(Maglev) system. Maglev system is eco-friendly used in a place that is not friction. But Maglev is system that inductance is changed according to air-gap, so this is unstable system. In this paper, we simulate 1 Maglev actuator Control and we do an experience on 4 Maglev actuator system control. however, we get a problem of 4 maglev actuator control, because Maglev is 3 DOF(Degree of Freedom). so we control average err of 2 Maglev actuator in the rear.

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평판압연공정 유한요소해석의 분산병렬처리에 관한 연구 (Finite element analysis of strip rolling process using distributive parallel algorithm)

  • 권기찬;윤성기
    • 대한기계학회논문집A
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    • 제21권12호
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    • pp.2096-2105
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    • 1997
  • A parallel approach using a network of engineering workstations is presented for the efficient computation in the elastoplastic analysis of strip rolling process. The domain decomposition method coupled with the frontal solver for elimination of internal degrees of freedom in each subdomain is used. PVM is used for message passing and synchronization between processors. A 2-D plane strain problem and the strip rolling process are analyzed to demonstrate the performance of the algorithm and factors that have a great effect on efficiency are discussed. In spite of much communication time on the network the result illustrates the advantages of this parallel algorithm over its corresponding sequential algorithm.

DEVELOPMENT OF A 3-DOF ROBOT FOR HARVESTING LETTUCE USING MACHINE: VISION AND FUZZY LOGIC CONTROL

  • S. I. Cho;S. J. Chang;Kim, Y. Y.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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    • pp.354-362
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    • 2000
  • In Korea, researches on year-round leaf vegetables production system are in progress, most of them focused on environmental control. Therefore, automation technologies for harvesting, transporting, and grading are in great demand. A robot system for harvesting lettuces, composed of a 3-DOF (degree of freedom) manipulator, an end-effector, a lettuce feeding conveyor, an air blower, a machine vision system, six photoelectric sensors, and a fuzzy logic controller, was developed. A fuzzy logic control was applied to determine appropriate grip force on lettuce. Leaf area index and height were used as input variables and voltage as an output variable for the fuzzy logic controller. Success rate of the lettuce harvesting was 94.12%, and average harvesting time was approximately 5 seconds per lettuce.

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일반화 전달강성계수법과 유전알고리즘을 이용한 골조구조물의 최적설계 (Optimum Design of Frame Structures Using Generalized Transfer Stiffness Coefficient Method and Genetic Algorithm)

  • 최명수
    • 동력기계공학회지
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    • 제9권4호
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    • pp.202-208
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    • 2005
  • The genetic algorithm (GA) which is one of the popular optimum algorithm has been used to solve a variety of optimum problems. Because it need not require the gradient of objective function and is easier to find global solution than gradient-based optimum algorithm using the gradient of objective function. However optimum method using the GA and the finite element method (FEM) takes many computational time to solve the optimum structural design problem which has a great number of design variables, constraints, and system with many degrees of freedom. In order to overcome the drawback of the optimum structural design using the GA and the FEM, the author developed a computer program which can optimize frame structures by using the GA and the generalized transfer stiffness coefficient method. In order to confirm the effectiveness of the developed program, it is applied to optimum design of plane frame structures. The computational results by the developed program were compared with those of iterative design.

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PCF 기법을 이용한 광디스크 드라이브의 진동원 규명 (The Identification of Vibration Sources in Optical Disk Drive Using PCF Method)

  • 함경훈;장영배;박노철;박영필
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.127-133
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    • 2002
  • After the vibration source is searched in optical disk drive as an information storage device broadly used the influence of it against FES(Focusing Error Signal) which is a kind of positioning error of pick up from the circuit is carefully examined. For that Purpose, partial coherence function method is applied on a simple multi-degree of freedom model made for the theoretical verification and it is practically introduced in optical disk drive for analyzing the effect of vibration source. Finally, partial coherence output spectrum is attentively observed in order to know which vibration source is a great influence on FES.

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단순화된 기준에 기반한 경추안마기 구동부 설계안의 평가 (Evaluation of Design Variants of Drive Mechanisms for a Neck Massager based on a Simplified Criterion)

  • 박정현;김권희;채수원;조창희
    • 한국정밀공학회지
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    • 제32권1호
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    • pp.83-88
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    • 2015
  • At the early stages of engineering design, a number of design concepts may be suggested. With a great degree of freedom, making a good choice may be a challenge at this stage. In this study, a simplified evaluation criterion for design concepts is presented based on cost, simplicity and safety. Cost is estimated by the amount of materials and the required level of tolerance. Simplicity is represented by the number of parts, assembly steps, and fasteners. Safety is assessed by the level of potential failure. The proposed criterion is applied to an example design of driving mechanisms for cervical vertebrae massage machine.