• 제목/요약/키워드: dead

검색결과 3,297건 처리시간 0.028초

Dynamic data Path Prediction in Network Virtual Environment

  • Jeoung, You-Sun;Ra, Sang-Dong
    • Journal of information and communication convergence engineering
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    • 제5권2호
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    • pp.83-87
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    • 2007
  • This research studies real time interaction and dynamic data shared through 3D scenes in virtual network environments. In a distributed virtual environment of client-server structure, consistency is maintained by the static information exchange; as jerks occur by packet delay when updating messages of dynamic data exchanges are broadcasted disorderly, the network bottleneck is reduced by predicting the movement path by using the Dead-reckoning algorithm. In Dead-reckoning path prediction, the error between the estimated and the actual static values which is over the threshold based on the shared object location requires interpolation and multicasting of the previous location by the ESPDU of DIS. The shared dynamic data of the 3D virtual environment is implementation using the VRML.

자동차 항법용 혼합항법 알고리즘 개발 (Development of the hybrid algorithm for the car navigation system)

  • 김상겸;양승규;김정하
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.1403-1406
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    • 1997
  • Generally, G.P.S(Global Positioning System) is using for the car navigation system but it has some restrictions such as the discontinuity of earth satellites and SA (Selective Availability). Recently, the hybrid navigation system combining with G.P.S and Dead-reckoning are much attractuve for improving the accuracy of a vehicle positioning. G.P.S called satellite navigation system, can measure its position by using satellites. Dead-Reckoning is the self-contained navigatioin system using a wheel sensor for the vehicle velocity and a gyro sensor for the vehicle angular velocity. Some algorithm could be generated for finding the vehicle position and orientation. In this paper, we developed a hybrid algotithm wiht G.P.S DR and Map-Matching.

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영구자석 동기 전동기의 MRAS 관측기를 이용한 Dead Time 보상에 대한 연구 (Study on Dead Time Compensation using MRAS Observer of Permanent Magnet Synchronous Motor.)

  • 김종현;김학원;조관열;임병국
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2013년도 추계학술대회 논문집
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    • pp.41-43
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    • 2013
  • PMSM 구동을 하였을 때, 인버터의 지령전압과 출력전압 사이에 왜곡이 발생하며, 대부분 Dead Time에 의한 영향 이다. 전압왜곡을 보상하는 여러 가지 방법 들이 연구되어왔다. 하지만 전압 왜곡의 보상이 abc 축 또는 dq축에서 이루어지고 있으나 어느 방식이 더 좋은지에 대한 검토가 없었다. 본 논문에서는 d-q축 전압방정식과 abc축 전압방정식으로부터 왜곡된 전압을 보상하는 방법을 비교한다.

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색소 농도에 따른 형광 광자의 계수율 : 광자 검출기의 dead time 효과 (Fluorescence photon counting rate as a function of dye concentration: Effect of dead time of photon detector)

  • 고동섭
    • 한국광학회지
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    • 제8권4호
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    • pp.353-355
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    • 1997
  • 공초점 형광 현미경과 단일 광자 계수기로 구성되어 있는 단일 분자 검출장치를 사용하여, 색소 농도에 따른 광자 계수율의 변화를 관측하였다. 농도가 증가함에 따라 계수율이 포화하는 경향을 보였으며, 광검출기의 죽은 시간을 고려하여 측정 결과를 설명하였다. 계수율과 검출 부피, 광검출기의 양자효율, 입사 광량 사이의 관계를 나타내는 관계식을 제시하였다. 또한 신호대 잡음비에 대해서도 간략하게 논하였다.

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멀티센서 데이터 융합에 의한 차륜형 이동체 위치추정시스템의 정도 개선에 관한 연구 (A Study on the Improvement of the Accuracy of a Wheeled Vehicle Positioning System by Multisensor Data Fusion)

  • 최진규;하윤수
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권1호
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    • pp.119-126
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    • 2000
  • In constructing the positioning system based on a conventional dead-reckoning for a wheeled vehicle with pneumatic tires, the position estimation error is inevitable as changes of the radius of the wheels depend on live load and variable enviroment. Therefore, this paper proposes the positioning system which can estimate the error source i.e. the vehicle parameter errors, such as the right and left wheel radius error, using gyroscope and ultrasonic sensor and correct the parameter to reduce the dead-reckoned position estimation error. The extended Kalman filter was used as a method for the multisensor data fusion. The simulation to verify the effectiveness of the proposed positioning system is performed.

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사각방지용 자동차 측면거울의 개발에 관한 연구 (A Study on the Sculptured surface mold by using CAM system)

  • 신근하
    • 한국생산제조학회지
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    • 제9권2호
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    • pp.119-124
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    • 2000
  • In this paper based on geometric optics and geometric modeling aspheric surface of the side mirror mold with dead angle reduced have been designed and machined in a CNC machining center, Surface roughness of the mold was evaluat-ed by usin the surface shaping system. Surface generating simulation of a ball endmill process is investigated. Through the simulation based on the surface-shaping system 3-D engineered surfaces and properties of engineered surfaces are obtained, Computer simulation provides the effective working conditions through the prediction of geometric properties of engineered surfaces. The rear view mirror and room mirror play important role on the safe driving condition as a observation of environment but the rear view mirror can not provide complete information of driving environments due to the existence of the dead angle. The analysis on the shape of formed mirror shows that the proposed me? improves range of a driver's sight.

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유압모터의 설계변수에 대한 특성 검토 (Characteristics Analysis of the Hydraulic Motor Design Variables)

  • 류량량;장주섭
    • 한국자동차공학회논문집
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    • 제21권4호
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    • pp.188-194
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    • 2013
  • Hydrostatic pumps and motors occupy an important position in hydraulic system. There are a lot of researches on characteristics of hydraulic pumps, but not hydraulic motors. So in order to know the characteristics of hydraulic motors we had this research. The purpose of this study is to derive and analyze the theoretical calculation of hydraulic axial piston motor torque and torque ripples. Then, analyzed the differences between torque ripples with dead place and without dead place on the valve plate, and modeling a hydraulic motor with AMESim software. Finally, theoretical calculation of hydraulic motor torque ripples was verified from the viewpoint of simulation.

농업 부산물을 이용한 돼지 사체 퇴비화 (Composting Dead Swine by Using Agricultural Residues)

  • 홍지형;최병민
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 1998년도 학술발표회 발표논문집
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    • pp.473-478
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    • 1998
  • Dead animals amended with agricultural rersidues are utilized ai a compost to promote soil fertility and reduce environmental pollution by traditional methods of livestock mortalities. The full-scale bin composting swine mortality in roofed system with three amendments was very successful in reaching sufficient temperature above 55$^{\circ}C$ long enough for pathogen kill. The average temperature of tile compost material in dead swine amended with corn stover increased rapidly to 64$^{\circ}C$ on the 2nd day after primary composting and dropped to near ambient temperature on the 140th day of composting. The composting temperature of corn stover and wheat straw is more efficient for swine carcass composting than that of sawdust.

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계획항로를 활용한 해상교통관제사 의사결정 지원 방안

  • 김주성;정중식;박계각;김윤하;김계수
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2014년도 춘계학술대회
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    • pp.287-289
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    • 2014
  • 선박의 선위 추측(DR, Dead Reckoning)은 수신되거나 측정된 위치 데이터와 속력, 침로 데이터만을 반영하여 계산하므로 대양의 항해나 연근해의 해역에서는 유효할 수 있으나 침로의 변경과 선속의 변화가 잦은 항계 내의 조선에 있어서는 적용이 어렵다는 문제점이 있다. 본 논문에서 제안하는 선박의 추측위치(DRP, Dead Reckoning Position)는 선박의 운항 패턴에 따라 항계 내의 항적 데이터를 수집하고, 수신된 위치 데이터와 속력, 침로 데이터를 점장위도항법(Mercator Sailing)을 통하여 계획항로(Planned Route)의 각 변침점(WP, Waypoint)간 침로(Course)와 항정(Ship's Passage)에 반영하였다. 제안된 추측위치 산출방법을 통하여 항계 내의 조선과정에서 계획항로를 선박의 추측위치와 결합하여 특정 시간 후의 상황패턴을 미리 예측하고 관제사의 의사결정에 기여하고자 한다.

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Decentralized Load-Frequency Control of Interconnected Power Systems with SMES Units and Governor Dead Band using Multi-Objective Evolutionary Algorithm

  • Ganapathy, S.;Velusami, S.
    • Journal of Electrical Engineering and Technology
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    • 제4권4호
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    • pp.443-450
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    • 2009
  • This paper deals with the design of decentralized controller for load-frequency control of interconnected power systems with superconducting magnetic energy storage units and Governor Dead Band Nonlinearity using Multi-Objective Evolutionary Algorithm. The superconducting magnetic energy storage unit exhibits favourable damping effects by suppressing the frequency oscillations as well as stabilizing the inter-area oscillations effectively. The proposed control strategy is mainly based on a compromise between Integral Squared Error and Maximum Stability Margin criteria. Analysis on a two-area interconnected thermal power system reveals that the proposed controller improves the dynamic performance of the system and guarantees good closed-loop stability even in the presence of nonlinearities and with parameter changes.