• Title/Summary/Keyword: power-assist

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A Study on the Collision Detection for Smart Door by Disturbance Observer (외란관측기를 이용한 스마트도어의 충돌감지에 관한 연구)

  • Park, Min-Kyu;Sung, Kum-Gil;Lee, Byungsoo
    • Journal of the Korean Society of Mechanical Technology
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    • v.13 no.4
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    • pp.31-36
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    • 2011
  • Smart Door(SD) is a human friendly power-assisted door system for passenger car doors. It offers comfort and safety to passengers and drivers by supplying additional power. In this study, dynamic system model and the equation of motion derivation are derived. And we propose the disturbance observer based collision detection algorithm for safety when opening the door. A disturbance caused by collision has a fast response compared to a friction, uncertainties and so on. The main idea this study is to estimate a variation of disturbance for stably and effectively detecting a collision. In order to evaluate a performance of collision detection, an experiment set up is constructed. The experimental results validate the usefulness of the proposed collision detection algorithm.

Resource allocation in downlink SWIPT-based cooperative NOMA systems

  • Wang, Longqi;Xu, Ding
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.1
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    • pp.20-39
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    • 2020
  • This paper considers a downlink multi-carrier cooperative non-orthogonal multiple access (NOMA) transmission, where no direct link exists between the far user and the base station (BS), and the communication between them only relies on the assist of the near user. Firstly, the BS sends a superimposed signal of the far and the near user to the near user, and then the near user adopts simultaneous wireless information and power transfer (SWIPT) to split the received superimposed signal into two portions for energy harvesting and information decoding respectively. Afterwards, the near user forwards the signal of the far user by utilizing the harvested energy. A minimum data is required to ensure the quality of service (QoS) of the far user. We jointly optimize power allocation, subcarrier allocation, time allocation, the power allocation (PA) coefficient and the power splitting (PS) ratio to maximize the number of data bits received at the near user under the energy causality constraint, the minimum data constraint and the transmission power constraint. The block-coordinate descent method and the Lagrange duality method are used to obtain a suboptimal solution of this optimization problem. In the final simulation results, the superiority of the proposed NOMA scheme is confirmed compared with the benchmark NOMA schemes and the orthogonal multiple access (OMA) scheme.

Knowledge Engineering Method Ie Estimation of Snow Accretion on Power lines and Decision of Deicing Countermeasures (지식공학에 의한 전선 착설 예측 및 대책 결정 기법)

  • 최규형
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.3
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    • pp.95-102
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    • 2003
  • To Prevent the damage of power system facilities by snow accretion on transmission lines, a prototype expert system has been developed. The system has the basic functions of forecasting snow accretion on transmission lines and making a list of all feasible and effective deicing countermeasures to assist power system operators. As estimating of snow accretion on power lines and making countermeasure plans are very difficult to solve analytically, knowledge engineering can be an effective method for this problem. The heuristics about the effect of weather conditions on the snow accretion process on power lines and power system operation for the deicing constitutes main nile base. Simulation results based on past snow accretion accident data show that the proposed system is very premising.

Late epoch of IT and dreamy appearance society - We may define alternately human beings are - (기술사마당_기술해설 - 후기정보화시대와 꿈같은 우리사회의 모습 -인간을 '재정의(再定義)' 할지도-)

  • Cho, Myong-Jae
    • Journal of the Korean Professional Engineers Association
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    • v.43 no.1
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    • pp.54-57
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    • 2010
  • The status of near future in IT era is described. Aging, Woman power, Home alone, Glovalization and Rapid growth of technology are characterised in these category. Specialy nano bio technology and Robotics would be contributed in progress of medical sector. It could assist anti-aging. The efficiency of computer rapidly grow by artificial intelligence. Dr.Toffler who is the futurist said that the key word passing through the 21st century as the definition of a human being might be changed.

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The Development of the Interface Tool for the Designing of Motor Drive Using Spice (Motor Drive 설계를 위한 Spice 용 Interface Tool 제작)

  • 이상용;고재석;목형수;최규하;최홍순;김덕근
    • Proceedings of the KIPE Conference
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    • 1998.11a
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    • pp.68-72
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    • 1998
  • The parameter through the motor designing program is used to predict motor response and design the motor drive circuits. The application programs such as "Saber" are often used for these. However, making the electrical model of motor for these simulation tool is uncomfortable and impossible for general users. Therefore, in this paper, we develop the "Spice" library generation program with the motor designing program "Motor Expert". This program will assist the user to make the motor library comfortablely and correctlyry comfortablely and correctly

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Export System Approach for Snow Accretion on Transmission Lines (전문가시스템에 의한 전선착설예측)

  • Choi, Kyu-Hyeong
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.193-195
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    • 1992
  • Snow accretion on transmission lines may cause critical accidents such as sleet jump, tower collpases, etc,. In order to assist power system operators to prevent thses accidents, aprototype expert system had been developed. The system has basic functions of forecasting snow accretion on transmission lines and making a list of all feasible and effective deicing countermeasures. The knowledge of the effect of weather conditions on the snow accretion process continue main rule base. Simulation results show that the proposed system is very promising.

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A Study on System Requirement Structure of Urban Transit System (도시철도시스템의 요구사항체계 구축에 관한 연구)

  • Lee Woo-Dong
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.157-161
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    • 2004
  • Urban transit is system that offer target Performance and function because various lower part system such as vehicles, signaling, power supply, rail track is consisted as complex. It is important first of all that describe correctly system requirement until configuration of system, design, manufacture, installation and test verification so that the complicated urban transit system is to act safety and reliable and to display target Performance and function properly. The system requirement assist the system developer to comprehensive the performance and function of system in basic design. Therefore, In this paper wishes to study way to analyze system of system requirement and apply to Urban transit.

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Evaluation Of Public Investment Project Using AHP (계층화 의사결정법에 의한 공공사업 투자안 평가에 관한 연구)

  • 김형준;이공섭;김영민
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.18 no.35
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    • pp.123-130
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    • 1995
  • The analytic hierarchy process(AHP) is a multi-criteria decision methodology developed by T.L.Saaty(1980). The AHP presents flexible, easily understood wry to assist the decision-marker in formulating his problem in a logical and rational manner. This paper addresses the concept of AHP and its application in the evaluation of nuclear and coal-fired power generations.

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EVALUATION OF LAGRANGIAN AND EULERIAN APPROACHES FOR PREDICTION OF HEMOLYSIS IN BLOOD PUMPS (혈액펌프내 혈액 변성 예측에 대한 Lagrangian 및 Eulerian 기법의 평가)

  • Hong, S.;Son, C.;Kang, S.;Hur, N.;Kim, W.;Kang, S.H.
    • Journal of computational fluids engineering
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    • v.20 no.3
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    • pp.79-86
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    • 2015
  • A blood pump is an important part of a cardiac assist device. Since the shear rate in blood is known to be a primary factor on hemolysis generation, it has been very important to evaluate hemolysis inside blood pumps for understanding performance and reliability of cardiac assist devices. In this study, hemolysis generation inside blood pumps is analyzed using CFD with power-law based models for the blood damage index(BDI), in order to overcome difficulties in measuring hemolysis by experiment. The BDI values in blood pumps can be evaluated using Lagrangian or Eulerian approaches. In this study, several Lagrangian and Eulerian approaches are compared to estimate the efficiency of the numerical methods in a practice sense. It is found that the Eulerian approaches are advantageous in terms of the efficiency and robustness. Two different Eulerian approaches are used to evaluate the BDI values of a few commercial blood pumps. For the conditions of extracorporeal membrane oxygenator(ECMO) and ventricular assist device(VAD), local generation of hemolysis is analyzed using divided regions of blood pumps, in order to investigate the effects of the pump geometry.