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검색결과 183건 처리시간 0.031초

Real time trajectory control for two wheeled mobile robot under dynamic environments

  • Lee, Jin-Woo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.120.4-120
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    • 2001
  • In this paper, a method of generating trajectories in real time for a mobile robot in a dynamic environment is proposed. Specifically, this method is focused on soccer-playing robots that need to calculate trajectories in real time, which are constantly subject to rapidly change as targets and obstacles move. The robots also should move at the fastest available speed, while tracking the generated trajectories. The method proposed in this paper solves the geometric problem of finding a smooth curve that joins two endpoints. To have this solved, we assign five constraints to each endpoint, which are the usual x, y, theta, and curvature as well as the influence of the initial robot velocity on the path. With these five constraints, the path generated can always be physically followed by robot. Through this method, the travel time of the robot over the entire path can b optimized. Therefore it can ...

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단상 하이브리드 SRM의 위치 추정 방법 (Position Estimation Method of Single-Phase Hybrid SRM)

  • 탕잉;;이동희;안진우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.737-739
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    • 2015
  • In this paper, a novel method of sensorless control scheme is proposed to apply on a single phase hybrid SRM used in high speed operation. The proposed method utilizes beneficially permanent magnet field whose performance is motor parameter independent to estimate the rotor position. Also, the current slope is adopted to complete the sensorless control when the motor running with heavy torque at high speed condition. Through this approach, the adjustable turn on/off position can be achieved without prior knowledge of inductance profile which is always employed by many sensorless schemes. And this paper may offer an available method to do the sensorless control in hybrid SRM used for high speed running.

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기술획득 전략에 따른 e-로지스틱스 통합화 방안 사례연구 (A Study on e-Logistics Integration Scheme Using A Strategy of Technical Acquisition)

  • 서장훈;박명규
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2003년도 추계학술대회
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    • pp.105-111
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    • 2003
  • This paper examines to focus on General Strategy of e-logistics activity for SCM(Supply Chain Management) Build-up, especially the field service logistics Integration. And this research analyzes the case study (Business of Strategy Group Unit) Survey) involving effective logistics management that leads customer satisfaction, seeking to find out the key elements of competitive policy. Because problems arise from the differences between their goals and structures, which cause each sied to feel vulneralbe to opportunism or shirking of responsibilities by the other. The goal of a logistics system is to ensure that every family planning client always receives the contraceptives partner wants, and that they are in good condition and have not expired. In order to select, procure, and distribute the right Quantities of the right contraceptives, managers of the logistics system must keep informed of the rates of use of each contraceptive and of the Quantity of available supplies. As a result, We propose that a firm's e-logistics strategy is an important locus innovation and a crucial source of value creation for the firm its suppliers, partners, and customers.

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IA를 이용한 전력시스템 고조파 상태 추정 최적 알고리즘 (An Optimal Algorithm of Harmonic State Estimation using Immune Algorithm on Power System)

  • 박인표;왕용필;정형환;박희철;안병철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 A
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    • pp.92-94
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    • 2003
  • The design of a measurement system to perform Harmonic State Estimation(HSE) is a very complex problem. In particular, the number of available harmonic instruments (Continuous Harmonic Analysis in Real Time : CHART) is always limited. Therefore, a systematic procedure is needed to design the optimal placement of measurement points. This paper presents an optimal algorithm of HSE which is based on an optimal placement of measurement points using Immune Algorithm (IAs). This HSE has been applied to power system for the validation of an optimal algorithm of HSE. The study results have indicated an economical and effective method for optimal placement of measurement points using IAs in the HSE.

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Fire design of concrete encased columns: Validation of an advanced calculation model

  • Zaharia, R.;Dubina, D.
    • Steel and Composite Structures
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    • 제17권6호
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    • pp.835-850
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    • 2014
  • The fire resistance of composite steel and concrete structures may be determined by using the simplified methods provided in EN 1994-1-2. For the particular situations not covered by the standard, an advanced calculation model might be applied, using special purpose programs for the analysis of structures in fire. The validation of these programs has always been an important issue for software developers, but also for designers and authorities. Clause 4.4.4 from EN 1994-1-2 refers to the validation of the advanced calculation models and states that these models must be validated through relevant test results. The paper presents the calculation of fire resistance of the composite columns in a high-rise building built in Romania, and focusses on the validation of the calculation model (computer program SAFIR), for this particular case. This validation, asked by the Romanian authorities, considers the available experimental results of a fire test, performed on a similar composite steel-concrete column.

연속식 탈선계수 측정기술 (Measuring Technology of Continuous Method for Derailment Coefficient)

  • 유원희;함영삼
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.138-143
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    • 2006
  • Oscillatory wheel load fluctuation of considerable amplitude is almost always observed on railway vehicle running at high speed. From the acceleration measured on the axle-box, the frequency of this fluctuation is estimated to be approximately within 70 Hz. By the conventional measuring method, continuous outputs of wheel load can not be obtained, so it is difficult to investigate such a high frequency phenomenon exactly. We have developed a new method of measuring the forces and derailment coefficient continuously, using two pairs of strain gauge bridges whose output phases are shifted by 90 degree, and summing up the outputs with a weighting function. This method is available for measuring the forces between wheel and rail up to high frequency. In this paper, continuous method of measuring forces between wheel and rail and derailment coefficient.

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단상 하이브리드 SRM의 센서리스 제어기법 (A Sensorless Control Method of Single-Phase Hybrid SRM)

  • 탕잉;이동희;안진우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2015년도 전력전자학술대회 논문집
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    • pp.507-509
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    • 2015
  • In this paper, a novel method of sensorless control scheme is proposed to apply on a single phase hybrid SRM used in high speed operation. The proposed method utilizes beneficially permanent magnet field whose performance is motor parameter independent to estimate the rotor position. Also, the current slope is adopted to complete the sensorless control when the motor running with heavy torque at high speed condition. Through this approach, the adjustable turn on/off position can be achieved without prior knowledge of inductance profile which is always employed by many sensorless schemes. And this paper may offer an available method to do the sensorless control in hybrid SRM used for high speed running.

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단상 하이브리드 SRM의 센서리스 제어기법 (Sensorless Control Method of Single-Phase hybrid SRM)

  • 탕잉;;이동희;안진우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2015년도 추계학술대회 논문집
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    • pp.213-214
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    • 2015
  • In this paper, a novel method of sensorless control scheme is proposed to apply on a single phase hybrid SRM used in high speed operation. The proposed method utilizes beneficially permanent magnet field whose performance is motor parameter independent to estimate the rotor position. The differential value of back-EMF is used to detect its peak point when there is no current conducting in the winding. Through this approach, the adjustable turn on/off position can be achieved without prior knowledge of inductance profile which is always employed by many sensorless schemes. And this paper may offer an available method to do the sensorless control in hybrid SRM used for high speed running.

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기술획득 전략에 따른 e-로지스틱스 통합화 방안 사례연구 (A Study on e-Logistics Integration Scheme Using A Strategy of Technical Acquisition)

  • 김종기;서장훈;박명규
    • 대한안전경영과학회지
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    • 제5권4호
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    • pp.117-130
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    • 2003
  • This paper examines to focus on General Strategy of e-logistics activity for SCM(Supply Chain Management) Build-up, especially the field service logistics Integration. And this research analyzes the case study(Business of Strategy Group Unit) Survey) involving effective logistics management that leads customer satisfaction, seeking to find out the key elements of competitive policy. Because problems arise from the differences between their goals and structures, which cause each sied to feel vulneralbe to opportunism or shirking of responsibilities by the other. The goal of a logistics system is to ensure that every family planning client always receives the contraceptives partner wants, and that they are in good condition and have not expired. In order to select, procure, and distribute the right quantities of the right contraceptives, managers of the logistics system must keep informed of the rates of use of each contraceptive and of the quantity of available supplies. As a result, We propose that a firm's e-logistics strategy is an important locus innovation and a crucial source of value creation for the firm its suppliers, partners, and customers.

레지스터 재활용 사슬의 체계적 생성 (A Systematic Generation of Register-Reuse Chains)

  • 이혁재
    • 대한전기학회논문지:전력기술부문A
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    • 제48권12호
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    • pp.1564-1574
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    • 1999
  • In order to improve the efficiency of optimizing compilers, integration of register allocation and instruction scheduling has been extensively studied. One of the promising integration techniques is register allocation based on register-reuse chains. However, the generation of register-reuse chains in the previous approach was not completely systematic and consequently it creates unnecessarily dependencies that restrict instruction scheduling. This paper proposes a new register allocation technique based on a systematic generation of register-reuse chains. The first phase of the proposed technique is to generate register-reuse chains that are optimal in the sense that no additional dependencies are created. Thus, register allocation can be done without restricting instruction scheduling. For the case when the optimal register-reuse chains require more than available registers, the second phase reduces the number of required registers by merging the register-reuse chains. Chain merging always generates additional dependencies and consequently enforces the execution order of instructions. A heuristic is developed for the second phase in order to reduce additional dependencies created by merging chains. For matrix multiplication program, the number of registers resulting from the first phase is small enough to fit into available registers for most basic blocks. In addition, it is shown that the restriction to instruction scheduling is reduced by the proposed merging heuristic of the second phase.

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