• 제목/요약/키워드: Moving Time

검색결과 3,702건 처리시간 0.03초

A Laplacian Autoregressive Moving-Average Time Series Model

  • Son, Young-Sook
    • Journal of the Korean Statistical Society
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    • 제22권2호
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    • pp.259-269
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    • 1993
  • A moving average model, LMA(q) and an autoregressive-moving average model, NLARMA(p, q), with Laplacian marginal distribution are constructed and their properties are discussed; Their autocorrelation structures are completely analogus to those of Gaussian process and they are partially time reversible in the third order moments. Finally, we study the mixing property of NLARMA process.

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판재성형 가공에서의 다축 단동 유닛을 이용한 복합금형용 Double-moving System 개발 (A development of double-moving system for composite die using multi-axis shuttle unit in the sheet metal forming)

  • 김동욱;최계광
    • Design & Manufacturing
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    • 제10권2호
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    • pp.39-43
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    • 2016
  • Most of automobile parts manufactured through sheet metal forming are mass-produced by using press mold. In recent years, automation and speeding up of press lines have been expanding to maximize product productivity using a press die. The proportion of the moving time in the press line is high, and therefore requires high-speed and automated equipment for the moving process. In this paper, to provide the double-moving system can be the moving time reduction and increased productivity. Developed transport system consists of the material supply, the material feeding device and the PLC controller and the devices are positioned between each of the pressing process. In this paper, the double-moving system including developed units using a multi-axial single-acting through this reduced the C/T(cycle time) and improved the productivity.

이동 질량을 포함하는 능동형 공압제진대에 대한 시간지연제어기법의 적용 검토 (Examination on Active Pneumatic Vibration Isolation Table with Moving Masses on It by Time Delay Control)

  • 신윤호;문석준;정정훈;김병현
    • 한국소음진동공학회논문집
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    • 제21권9호
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    • pp.858-867
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    • 2011
  • As applying an active control technique to a pneumatic vibration isolation system, the settling time for the payload excitation could be remarkably reduced as well as the improvement of isolation performance for the ground vibration. Some previous researches were dealt with the settling time through the simulation or experiment but, the discussion on the simulation or experimental results including moving parts, such as a XY-stage, on the isolation table rarely exists. As considering the moving part, the dynamic model could be time varying system and in such a case the force imposed on pneumatic vibration isolation table could be described by inertial forces of moving parts according to Newton's 3rd law, the action and reaction law. In this paper, the simulation procedure of the 3-DOF active pneumatic vibration isolation system including moving parts by TDC(time delay control) technique is proposed and the effectiveness through simulation results are also shown.

(sLb-Camera-pRc)타입의 겐트리 이동시간 단축 방법 (The method to reduce the travel time of the gentry in (sLb-Camera-pRc) type)

  • 김순호;김치수
    • 한국융합학회논문지
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    • 제10권9호
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    • pp.17-22
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    • 2019
  • SMT장비 인 겐트리는 전자 부품을 피더에서 흡착하여 기판위에 정확히 실장하는 장비이다. 이 때 부품이 정확히 흡착되었는지를 검사하기 위해 카메라 앞에서 겐트리는 잠시 멈춘다. 본 논문에서는 이동 시간을 단축하기 위해 카메라 앞에서 겐트리가 정지하지 않고 움직이면서 검사를 할 수 있는 방법을 제시한다. 이 방법은 여러 이동 경로 중 가장 빠른 시간에 이동할 수 있는 경로를 찾아 기존 방법보다 이동 시간이 단축됨을 보여준다. 제시된 방법(moving-motion)은 기존 방법(stop-motion)보다 겐트리의 이동 시간을 20%나 단축시킨다.

Research on detecting moving targets with an improved Kalman filter algorithm

  • Jia quan Zhou;Wei Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권9호
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    • pp.2348-2360
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    • 2023
  • As science and technology evolve, object detection of moving objects has been widely used in the context of machine learning and artificial intelligence. Traditional moving object detection algorithms, however, are characterized by relatively poor real-time performance and low accuracy in detecting moving objects. To tackle this issue, this manuscript proposes a modified Kalman filter algorithm, which aims to expand the equations of the system with the Taylor series first, ignoring the higher order terms of the second order and above, when the nonlinear system is close to the linear form, then it uses standard Kalman filter algorithms to measure the situation of the system. which can not only detect moving objects accurately but also has better real-time performance and can be employed to predict the trajectory of moving objects. Meanwhile, the accuracy and real-time performance of the algorithm were experimentally verified.

실시간 방송 지연을 위한 DELAY 모듈의 설계 및 구현 (The Design and Implementation of DELAY Module for Real-Time Broadcast Delay)

  • 안희학;구자영;이대식
    • 디지털산업정보학회논문지
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    • 제15권3호
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    • pp.45-53
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    • 2019
  • Moving image sharing technology has developed various servers and programs for personal broadcasting. In this paper, we propose the method of transmitting the multiple moving image, including the output channel of external streaming server. It also implements and tests multiple real-time broadcast channel automatic transmission systems that assign multiple output channels to automatic output channels. As a result of the experiment, it is easy to allocate moving image to broadcast channels that are output through the external streaming server's output channels regardless of the size of the streaming server, enabling the management of efficient output channels at the time of transmission of multiple moving image. The moving image can be provided through streaming method regardless of the type of moving image from the moving image provider terminal, and the moving image transmission can be controlled in various ways, including adding and changing channels for which the moving image is sent, and sending delayed to the moving image.

이동 표적에 의한 도플러 신호의 시간-주파수 분석 (Time-Frequency Analysis of the Doppler Signals by Moving Targets)

  • 손중탁;이승훈;박길흠
    • 한국군사과학기술학회지
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    • 제8권2호
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    • pp.38-48
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    • 2005
  • Instantaneous frequency of doppler signals is used to get the information of the relative velocity and the miss distance between a missile and a corresponding target. In this paper, we have performed time-frequency analysis and instantaneous frequency estimation with Short Time Fourier Transform(STFT), Wigner Ville Distribution(WVD) and Continuous Wavelet Transform(CWT) about the doppler signals generated by moving targets. Performance evaluation was performed using simulated doppler signals generated by a single moving target and two moving targets. From the results of the time-frequency analysis, we found that WVD method was the most efficient instantaneous frequency estimator among the three methods. But in case of two moving targets, WVD method got cross talks and CWT method got oscillation when two doppler frequencies were close to each other.

Design of Moving Objects Server for Location Based Services

  • Cho, Dae-Soo;Min, Kyoung-Wook;Lee, Jong-Hun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.157-162
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    • 2002
  • Recently, location based services, which make use of location information of moving objects, have obtained increasingly high attention. The moving objects are time-evolving spatial objects, that is, their locations are dynamically changed as time varies. Generally, GIS server stores and manages the spatial objects, of which locations are rarely changed. The traditional GIS server, however, has a difficulty to manage the moving objects, due to the fact of locations being frequently changed and the trajectory information (past locations of moving objects) being managed. In this paper, we have designed a moving object server, which stores and manages the locations in order to support various location based services. The moving object server is composed of a location acquisition component, a location storage component, and a location query component. The contribution of this paper is that we integrate the each work for location acquisition, storage, and query into a moving objects server.

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연속류 시설의 이동병목구간에서 지체산정방법 -모의실험을 통한 교통류의 평균지체분석- (The Analysis of Traffic Flow Characteristics on Moving Bottleneck)

  • 김원규;정명규;김병종;서은채;김송주
    • 정보통신설비학회논문지
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    • 제8권4호
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    • pp.170-181
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    • 2009
  • When a slow-moving vehicle occupies one of the lanes of a multi-lane highway, it often causes queuing behind, unlike one is caused by an actual stoppage on that lane. This happens when the traffic flow rate upstream from the slow vehicle exceeds a certain critical value. This phenomena is called as the Moving Bottleneck, defined by Gazis and Herman (1992), Newell (1998) [3], and Munoz and Daganzo (2002), who conducted the flow estimates of upstream and downstream and considered slow-moving vehicle speed and the flow ratio exceeding slow vehicle and the microscopic traffic flow characteristics of moving bottleneck. But, a study of delay on moving bottleneck was not conducted until now. So this study provides a average delay time model related to upstream flow and the speed of slow vehicle. We have chosen the two-lane highway and homogeneous traffic flow. A slow-moving vehicle occupies one of the two lanes. Average delay time value is a result of AIMSUN[9], the microscopic traffic flow simulator. We developed a multiple regression model based on that value. Average delay time has a high value when the speed of slow vehicle is decreased and traffic flow is increased. Conclusively, the model is formulated by the negative exponential function.

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Unstructured Moving-Grid Finite-Volume Method for Unsteady Shocked Flows

  • Yamakawa M.;Matsuno K.
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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    • pp.86-87
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    • 2003
  • Unstructured grid system is suitable for flows of complex geometries. For problems with moving boundary walls, the grid system must be changed and deformed with time if we use a body fitted grid system. In this paper, a new moving-grid finite-volume method on unstructured grid system is proposed and developed for unsteady compressible flows with shock waves. To assure geometric conservation laws on moving grid system, a control volume on the space-time unified domain is adopted for estimating numerical flux. The method is described and applied for two-dimensional flows.

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