• Title/Summary/Keyword: mechanical industry

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A Study on the Fracture Behavior of Quartz Glass(I) (석영 유리의 파괴 거동에 관한 연구(I))

  • Choi, Seong-Dae;Cheong, Seon-Hwan;Jeong, Young-Kwan;Kim, Gi-Man;Hong, Yong-Bae
    • Journal of the Korean Society of Industry Convergence
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    • v.10 no.3
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    • pp.179-185
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    • 2007
  • Quartz glass are used in semiconductor industries as the reaction furnace, wafer carrier and accessaries. During the process the quartz glass received compression by direct contact with other quartz glass ware and metal as the form of weight itself and vacuum pressure and fatigue by vibrations caused by process. Even as the other ceramic materials quartz glass have high compressive strength but often there happened crack and breakage of quartz glass resulted in a great damage in the process. In this paper investigation will be carried out on fracture behavior of quartz glass under local load to give guideline to prevent unintended fracture of quartz glass.

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Numerical Prediction of Acoustic Sounds Occurring by the Flow Around a Circular Cylinder

  • Kang, Ho-Keun;Ro, Ki-Deok;Michihisa Tsutahara;Lee, Young-Ho
    • Journal of Mechanical Science and Technology
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    • v.17 no.8
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    • pp.1219-1225
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    • 2003
  • Acoustic sounds generated by uniform flow around a two-dimensional circular cylinder at Re=150 are simulated by applying the finite difference lattice Boltzmann method. A third-order-accurate up-wind scheme is used for the spatial derivatives. A second-order-accurate Runge-Kutta scheme is also used for time marching. Very small acoustic pressure fluctuation, with same frequency as that of Karman vortex street, is compared with pressure fluctuation around a circular cylinder. The propagation velocity of acoustic sound shows that acoustic approaching the upstream, due to the Doppler effect in uniform flow, slowly propagates. For the downstream, on the other hand, it quickly propagates. It is also apparent that the size of sound pressure is proportional to the central distance ${\gamma}$$\^$-1/2/ of the circular cylinder.

A Study on Track Record and Trajectory Control of Articulated Robot Based on Monitoring Simulator for Smart Factory

  • Kim, Hee-Jin;Dong, Guen-Han;Kim, Dong-Ho;Jang, Gi-Won;Han, Sung-Hyun
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.2_1
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    • pp.149-161
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    • 2020
  • We describe a new approach to implement of trajectory control and track record of articulated manipulator based on monitoring simulator for smart factory. The learning control algorithm was applied in implementation real-time control to provide enhanced motion control performance for robotic manipulators. The proposed control scheme is simple in structure, fast in computation, and suitable for real-time control. Moreover, this scheme does not require any accurate dynamic modeling, or values of manipulator parameters and payload. Performance of the proposed controller is illustrated by simulation and experimental results for robot manipulator consisting of six joints at the joint space and Cartesian space.by monitoring simulator.

A Study on a New Approach to Robust Control and Torque Control Response Analysis of Manufacturing robot Based on Monitoring Simulator for Smart Factory

  • Kim, Hee-Jin;Kim, Dong-Ho;Jang, Gi-Won;Gu, Byeong-Hwa;Han, Sung-Hyun
    • Journal of the Korean Society of Industry Convergence
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    • v.24 no.4_1
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    • pp.397-409
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    • 2021
  • This study proposes a new approach to implimentation of robust control and torque control response analysis based on monitoring simulator for smart factory. According to the physical properties of a flexible manipulator, a two time-scale approach, namely, singular perturbation ap proach, is further utilized for thorough analysis and general controller design. It is shown that asymptotic motional tracking can be effectively achieved, whereas the force regulation errors can be made arbitrarily small. For demonstration of the proposed technology performance, experiments of a eight joint flexible manipulator are performed for the proposed control method, and the reliability of proposed control results are illustrated based on monitoring simulator.

A Study on an Intelligent Control of Manufacturing with Dual Arm Robot Based on Neural Network for Smart Factory Implementation (스마트팩토리 실현을 위한 뉴럴네트워크 기반 이중 아암을 갖는 제조용 로봇의 지능제어에 관한 연구)

  • Jung, Kum Jun;Kim, Dong Ho;Kim, Hee Jin;Jang, Gi Wong;Han, Sung Hyun
    • Journal of the Korean Society of Industry Convergence
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    • v.24 no.3
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    • pp.351-361
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    • 2021
  • This study proposes an intelligent control of manufacturing robot with dual arm based on neural network for smart factory implementation. In the control method of robot system, the perspectron structure of single layer based on neural network is useful for simple computation. However, the limitations of computation are emerging in areas that require complex computations. To overcome limitation of complex parameters computation a new intelligent control technology is proposed in this study. The performance is illustrated by simulation and experiments for manufacturing robot dual arm robot with eight axes.

Implementation of Assembly Line and Line Balancing to Improve Assembly Productivity-A Case Study (조립생산성 향상을 위한 조립라인 구축 및 라인 밸런싱 - ABS 모터를 중심으로)

  • Mok, Hak-Su;Jo, Jong-Rae;Pyo, Seung-Tae
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.8
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    • pp.129-138
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    • 2001
  • The paper presents an implementation procedure of assembly line for ABS motor, which is composed of four subassemblies-yoke, grommet, housing and armature. The characteristics of ABS motor and its assembly processes are analysed, and the automation possibility of each process is examined in order to decrease assembly time. The assembly machines and facilities are then selected for automatic assembly, and the layout of the selected facilities is determined. Finally, task allocation of each worker is achieved by assembly line balancing to increase assembly productivity and efficiency. The line efficiency is also analyzed using simulation.

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Methodology for Estimation of Assembly Time and Evaluation of Asseblability (조립시간 산정과 초립용이성 평가 방법론)

  • Mok, Hak-Soo;Cho, Jong-Rae;Kang, Young-Hun
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.5
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    • pp.72-80
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    • 2002
  • DFA (Design for assembly) is a design philosophy for improving product designs for simpler or less costly assembly operations. This paper proposes a new DFA methodology that can estimate the standard assembly time and evaluate the assemblablity of parts. We select some determining and influencing factors related with assembly process, and estimate the assembly time using motion analysis. By the levels of the determining and influencing factors, the assemblability is evaluated, and finally, the tables that include the time and score of assembly is suggested.