• Title/Summary/Keyword: delay

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Analysis of Response Characteristics of the CAN-Based Feedback Control System Considering the Network Delay Time

  • Jeon, Jong-Man;Kim, Dae-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.119.3-119
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    • 2001
  • When building a network-based real-time control system, a network-induced delay time should be surly considered for real time schedulability to be guaranteed. The network delay time on end-to-end communication has been analyzed theoretically and modeled mathematically from many previous works. There also exist any other delay element not considered before. In this paper, the remote feedback control system using the CAN protocol is proposed to control three axes´ manipulator arm and the application layer of CAN is modeled to analyze the delay elements defined by three types of time delay: Software delay time, Controller delay time, and Access delay time, in details. The analyzed results are used as an important component to determine PID gains of the proposed system. The effect of the delay time on the control performance is evaluated by com paring the response characteristics of the control system through simulation.

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A Register-Controlled Symmetrical Delay Locked Loop using Hybrid Delay Line (하이브리드 딜레이 라인을 이용한 레지스터 콘트롤 Symmetrical Delay Locked Loop)

  • 허락원;전영현
    • Proceedings of the IEEK Conference
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    • 2000.11b
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    • pp.87-90
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    • 2000
  • This paper describes a register-controlled symmetrical delay-locked-loop (DLL) using hybrid delay line for use in a high frequency double-data-rate DRAM. The proposed DLL uses a hybrid delay line which can cover two-step delays(coarse/fine delay) by one delay element. The DLL dissipate less power than a conventional dual-loop DLL which use a coarse and a fine delay element and control separately. Additionally, this DLL not only achieves small phase resolution compared to the conventional digital DLL's when it is locked but it also has a great simple delay line compared to a complex dual-loop DLL.

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Extraction of Optimal Time-Delay in Adaptive Command Shaping Filter for Flexible Manipulator Control (유연한 매니퓰레이터 제어를 위한 적응형 명령성형 필터의 최적 시간지연 값 추출)

  • Park, Joo-Han;Rhim, Sung-Soo
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.6
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    • pp.564-572
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    • 2008
  • The performance of the direct adaptive time-delay command shaping filter depends on the select time-delay. In the previously introduced direct adaptive command shaping filter, however, the time-delay value is fixed and only the magnitudes of the impulses are learned. In this paper, the authors introduce a new scheme to adapt the time-delay which is to be used in conjunction with the direct adaptive command shaping for the improved vibration suppression in flexible motion system. In order to formulate the time-delay adaptation scheme, the authors have analyzed the effect of the time-delay value on the performance of the direct adaptive command shaping filter. By modifying the direct adaptation formula based on the analysis result the authors have established a set of equations to adapt the time-delay toward the optimal value. Simulation results show the effectiveness of the proposed time-delay adaptation approach for the improved vibration suppression.

Performance Analysis of Telerobotic Systems with Different Haptic and Video Time-delay (햅틱과 영상의 시간지연 차이에 따른 원격조종 로봇시스템의 성능분석)

  • Kim, Ye-Seul;Ryu, Jee-Hwan
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.3
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    • pp.286-292
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    • 2010
  • In this paper, we investigate the relationship between the performance of telerobotic systems and the two independent time-delay on different modality, which are haptic and video. Especially, we try to find some performance improvement when the amount of delay of haptic and video is synchronized. Experiments were conducted with 10 subjects by scanning the amount of video and haptic delay independently. It is rather interesting to note that the teleoperation performance was not that sensitive to video delay, and the synchronized video and haptic delay doesn't show better performance than the case when haptic delay is lower than video delay.

An Efficient Delay Calculation Tool for Timing Analysis (타이밍 분석을 위한 효율적인 시간 지연 계산 도구)

  • Kim, Joon-Hee;Kim, Boo-Sung;Kal, Won-Koang;Maeng, Tae-Ho;Baek, Jong-Humn;Kim, Seok-Yoon
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.612-614
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    • 1998
  • As chip feature size decrease, interconnect delay gains more importance. A accurate timing analysis required to estimate interconnect delay as well as cell delay. In this paper, we present a timing-level delay calculation tool of which the accuracy is bounded within 10% of SPICE results. This delay calculation tool generates delay values in SDF(Standard Delay Format) for parasitic data extracted in SPEF(Standard Parasitic Exchange Format). The efficiency of the tool is easily seen because it uses AWE(Asymptotic Waveform Evaluation) algorithm for interconnect delay calculation, and precharacterized library and effective capacitance model for cell delay calculation.

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Delay of Gratification in Infancy : Effects of Infants' Temperament and Parenting

  • Rha Jong-Hay
    • International Journal of Human Ecology
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    • v.1 no.1
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    • pp.59-77
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    • 2000
  • The purpose of this study was to extend our understanding of the developmental antecedents of delay of gratification in infancy. The first goal was to examine direct effects of one feature of an infants’ temperament and of positive and negative parenting assumed at age one on children’s delay of gratification six months later. The second goal of the study was to test the interactive effect of early infant temperament and parenting on children’s delay of gratification. It was hypothesized that 1) less negative infants at 12 months would delay gratification longer six months later, 2) children of parents who provided more positive and sensitive feedback would delay gratification longer than children with parents who were more negative and less sensitive, and 3) there would be differential prediction of parenting for children who scored high and low in negative emotionality as infants. Toward this end, 81 infants were observed interacting at one year of age with their mothers and fathers during laboratory assessments to obtain measures of parenting and infant negative emotionality. At 18 months of age, the child’s capacity to delay touching attractive objects was measured. The main effects of infant negative emotionality and of mothering on children’s delay of gratification were not detected at standard levels of significance. Differential effects of parenting on children’s delay of gratification for infants with low or high negative emotionality, too, were not detected. However, the anticipated effect of fathering on delay of gratification was found in some analyses, indicating that the more positive fathering children received, the longer they could delay gratification in the laboratory six months later.

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Development of a methodology for analysing and quantifying the impact of delay factors affecting construction projects

  • Shebob, Abdulhamid;Dawood, Nashwan;Shah, Raj K.
    • Journal of Construction Engineering and Project Management
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    • v.2 no.3
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    • pp.17-29
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    • 2012
  • Delays are one of the biggest problems facing by the construction industry and they have significant financial and social impact in construction projects. The paper presents a framework of Delay Analysis System (DAS) with the aim of analysing the impact of delay factors in Libyan construction projects. The system has designed by integrating the possible delay factors, critical activities of a project using@risk simulator. A case study of building project was demonstrated to identify the impact of delays and the sensitivity of delay factor. The case study result showed that the project might be delayed by 97 to 103 days in comparison to the planned duration. The developed DAS is a tool for analysing and identify the impacts of delay factors and assist to construction manager to take necessary measure in reducing the delay impact. The paper provides a methodology for analysing the possible delay impact in a construction project and informing to construction manager in advance of the possible delay factors.

Factors associated with delay in reperfusion therapy in patients with acute myocardial infarction (급성심근경색 환자에서 재관류 치료 지연율과 그에 관련된 요인)

  • Kim, Yoon;Koh, Bong-Yeun
    • Health Policy and Management
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    • v.13 no.4
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    • pp.115-130
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    • 2003
  • Reperfusion delay in patients with acute myocardial infarction leads to increased morbidity and mortality. We sought to measure the rates of reperfusion delay and to identify factors associated with reperfusion delay after arrival to hospitals. We included 360 patients who had acute myocardial infarction with ST-elevation or left bundle branch block on electrocardiogram and received reperfusion therapy from the three participating academic medical centers from 1997 to 2000. Through retrospective chart review, we collected data about time to reperfusion therapy, patient and hospital factors potentially associated with reperfusion delay. Factors independently associated with reperfusion delay were determined by logistic regression analysis. Median door­to­needle time was 60.0 minutes, and median door­to­balloon time was 102.5 minutes. According to recommendation of the American College of Cardiology/American Heart Association Guidelines, 226 out of 264(85.6%) of thrombolytic patients and 43 out of 96(44.8%) percutaneous transluminal coronary angioplasty(PTCA) patients experienced reperfusion delay. The significant factors associated with delay were type of reperfusion therapy, patient factors including hypertension and delayed symptom onset to presentation(>4 hours), and hospital factors including nocturnal presentation(6pm∼8am), weekend, and an individual hospital. A significant proportion of patients experienced reperfusion delay. The identified predictors of reperfusion delay may help design a hospital system to reduce the delay in reperfusion therapy

Delay Factors Affecting the Completion of the Government Construction Projects in Vietnam

  • Kim, Soo-Yong;Nguyen, Viet Thanh;Luu, Van Truong
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.161-165
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    • 2015
  • The delay in construction is the challenge often faced in the course of executing construction projects. To the government projects, the delays become very serious. This problem directly affects the lives, social welfare of the people, and the other negative social impacts. However, the government projects have not been much interest. The questionnaire surveys in Vietnam were conducted to determine the causes of the delay and to find solutions for dealing with the delay. The average index was used to rank the delay factors and the solutions. This study identified the 5 most highly ranked delay factors and the 8 best solutions from a list of 31 delay factors and 19 solutions for the delay. The five most highly ranked delay factors were: information delays and lack of information exchange between the parties; incompetent owner; incompetent supervision consultant; incompetent contractor; and difficulties in financing project by owner. The findings of the study can help the parties involved the government construction projects and practitioners to give appropriate strategies for countering the delay in their projects.

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Performance Evaluation of Web-based Cloud Services in a Browser-Scripting Approach

  • Zhang, Chengwei;Hei, Xiaojun;Cheng, Wenqing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.6
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    • pp.2463-2482
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    • 2016
  • Cloud services are often provisioned to their customers using user-friendly web browsers with flexible and rich plug-in environments. Delay is one of the fundamental performance metrics of these web-based services. Commonly-used network measurement tools usually only measure network delay and it may be difficult to infer the web-delay performance using only network layer measurement approaches. In this paper, we propose to evaluate the application layer delay in a browser-based network measurement platform using engineered scripts. We conducted a delay measurement study using instrumented scripts in the proposed browser-based measurement platform. Our investigation included a comparison study of three browser-scripting delay measurement methods, including Java applet, JSP and Flash ActionScript. We developed a browser-based delay measurement testbed over the Internet so that different delay measurement tools could be evaluated in the same real network environment including typical Internet paths and the Baidu cloud. We also decomposed the components of the end-to-end delay process of the above measurements to reveal the difference and relationship between the network-layer delay and the application-layer delay. Our measurement results characterize the stochastic properties of the application-layer delay over real Internet paths, and how these properties vary from the underlying network layer delay. This browser-scripting measurement approach can be easily deployed on different cloud service platforms to inspect their application-layer delay performance between end clients and the cloud platforms. Our measurement results may provide insights into designing new cloud services with enhanced quality-of-experience perceived by cloud users.