• Title/Summary/Keyword: Data rate control

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Implementation and data operations of the robot workcell using the fieldbus (필드버스를 이용한 로봇웍셀의 구현과 자료운용)

  • 박세웅;김동준;김대원;이호길
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1249-1252
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    • 1996
  • With the expansion of research and development for the CIM and the IMS, the importance of introducing the communication network is being increased. This paper presents an implementation of robot workcell by using Fieldbus and investigates data operation of the robot workcell. Through experiments, the operations of periodic and real-time data, and non-periodic real-time data are studied. Also, the relationship between the network transmission rate and the monitoring results from the sensor is analyzed.

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Analysis of Characteristics of Optical Pickup Actuator for Tilt Control (틸트제어를 위한 광픽업 구동기의 특성 분석에 관한 연구)

  • Kim, Chul-Jin;Lee, Kyung-Taek;Park, No-Cheol;Park, Young-Pil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.377.2-377
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    • 2002
  • In optical disk drives (ODD), the demands of high data density and high speed have been increasing rapidly to achieve high data capacity and data transfer rate The use of short wavelength laser and high track following performance are needed to raise data density and data rate. For high-performance actuator, the improvement of linearity and acceleration become more important. (omitted)

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A Study on TCP-friendly Congestion Control Scheme using Hybrid Approach for Multimedia Streaming in the Internet (인터넷에서 멀티미디어 스트리밍을 위한 하이브리드형 TCP-friendly 혼잡제어기법에 관한 연구)

  • 조정현;나인호
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.837-840
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    • 2003
  • Recently the multimedia streaming traffic such as digital audio and video in the Internet has increased tremendously. Unlike TCP, the UDP protocol, which has been used to transmit streaming traffic through the Internet, does not apply any congestion control mechanism to regulate the data flow through the shared network. If this trend is let go unchecked, these traffic will effect the performance of TCP, which is used to transport data traffic, and may lead to congestion collapse of the Internet. To avoid any adverse effort on the current Internet functionality, A study on a new protocol of modification or addition of some functionality to existing transport protocol for transmitting streaming traffic in the Internet is needed. TCP-frienly congestion control mechanism is classified with window-based congestion control scheme and rate-based congestion control scheme. In this paper, we propose an algorithm for improving the transmitting rate on a hybrid TCP-friendly congestion control scheme combined with widow-based and rate-based congestion control for multimedia streaming in the internet.

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A Real-time Traffic Control Scheme for ATM network:RCT (ATM망을 위한 실시간 트래픽 제어 기법:RCT)

  • Lee, Jun-Yeon;Lee, Hae-Wan;Kwon, Hyeog-In
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.11
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    • pp.2822-2831
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    • 1997
  • A B-ISDN network based on ATM must support several kinds of transport services with different traffic characteristics and service requirements. There is neither link-by-link flow control nor error control in the ATM layer. For different services, different flow/error controls could be performed at the AAL layer or at a higher Iayer(e.g. transport layer). In traditional data networks, the window now control mechanism combined with error control was used prevalently. But, the window flow control mechanism might be useless in ATM networks because the propagation delay is too large compared with the transmission rate. In this paper, we propose a simple flow control mechanism, called RCT(Rate Control for end-to-end Transport), for end-to-end data transport. The RCT shows acceptable performance when the average overload period is bounded by a certain time.

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Historical Control Data for Developmental Toxicity Study in Sprague-Dawley Rats (Sprague-Dawley 랫드를 이용한 발생독성시험의 기초자료연구)

  • 김종춘;이상준;배진숙;박종일;김용범;정문구
    • Toxicological Research
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    • v.17 no.2
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    • pp.83-90
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    • 2001
  • The background control data were compiled from rat developmental toxicity studies con-ducted at Toxicology Research Center, KRICT during the 1993-1999 period. These data were assembled in order to provide background in formation for the maternal and fetal data collected in 13 developmental toxicity studies using Sprague-Dawley rats. A total of 325 mated females were used in these studies during the seven-year period and overall pregnancy rate of these females was 93.8%. The present background control data included body weights, food consumption, hematological values, and organ weights of pregnant females, caesarean section data, and fetal examination data. These data can be used not only as a historical database for the meaningful interpretation of data from reproductive and developmental toxicity studies, but also as a contribution to biological characterization oj Sprague-Dawley rats.

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UDT Parallel Transfer Technologies Adaptive to Network Status In High Speed Network (고속네트워크에서 네트워크 혼잡상태에 적응적인 UDT 병렬전송 기법)

  • Park, Jong Seon;Cho, Gi Hwan
    • Smart Media Journal
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    • v.2 no.4
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    • pp.51-59
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    • 2013
  • With increasing transmission speed of backbone networks, it is getting to provide enough available bandwidth. However, the bandwidth is not effectively utilized in volumetric data transfer. This mainly comes from the transmission protocol, TCP, which is used for most applications. TCP is inherently difficult to adapt the available bandwidth because of it's own characteristic of transfer mechanism. UDT is a prominent application level data transfer protocol which is targeting high speed network. In this paper, we propose UDT parallel transfer technologies which is adaptive to network status and then evaluate their performance in two points of view. Firstly, we measure data transfer rate of UDT with rate congestion control methods, and compare them with basic UDT. Secondly, we apply parallel transfer technologies adapted to network status, and measure their performance. Experimental results showed that UDT rate congestion control method outperforms UDT with 106% improvement in RTT 100ms section set with jitter 30ms. In addition, performance of parallel transfer with rate congestion control method showed 107% improvement than that of parallel transfer in RTT 400ms section set with jitter 20ms.

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A Real-Time Multimedia Data Transmission Rate Control Using Neural Network Prediction Model (신경 회로망 예측 모델을 이용한 실시간 멀티미디어 데이터 전송률 제어)

  • Kim, Yong-Seok;Kwon, Bang-Hyun;Chong, Kil-To
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.2B
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    • pp.44-52
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    • 2005
  • This paper proposes a neural network prediction model to improve the valid packet transmission rate for the QoS(Quality of Service) of multimedia transmission. The Round Trip Time(RTT) and Packet Loss Rate(PLR) are predicted using a neural network and then the transmission rate is decided based on the predicted RTT and the PLR. The suggested method will improve the transmission rate since it uses the rate control factors corresponding to time of data is being transmitted, while the conventional one uses the transmission rate determined based on the past informations. An experimental set-up has been established using a Linux PC system, and the multimedia data are transmitted using UDP protocol in real time. The valid transmitted packets are about 5% higher than the one in the conventional TCP-Friendly congestion control method when the suggested algorithm was applied.

Design and Comparison of Error Correctors Using Clustering in Holographic Data Storage System

  • Kim, Sang-Hoon;Kim, Jang-Hyun;Yang, Hyun-Seok;Park, Young-Pil
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1076-1079
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    • 2005
  • Data storage related with writing and retrieving requires high storage capacity, fast transfer rate and less access time in. Today any data storage system can not satisfy these conditions, but holographic data storage system can perform faster data transfer rate because it is a page oriented memory system using volume hologram in writing and retrieving data. System architecture without mechanical actuating part is possible, so fast data transfer rate and high storage capacity about 1Tb/cm3 can be realized. In this paper, to correct errors of binary data stored in holographic digital data storage system, find cluster centers using clustering algorithm and reduce intensities of pixels around centers. We archive the procedure by two algorithms of C-mean and subtractive clustering, and compare the results of the two algorithms. By using proper clustering algorithm, the intensity profile of data page will be uniform and the better data storage system can be realized.

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Simulation of the control force of the light aircraft using flight test data (비행시험 자료를 이용한 경항공기의 조종력 시뮬레이션)

  • 김정환;황명신;이정훈
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.203-206
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    • 1996
  • The purpose of this paper is to find how to determine the parameters of the basic control system design such as hinge moment coefficients and to display the controllability of the ChangCong-91. Since the estimation from the flight test of real aircraft is the most reliable, we performed the flight test of ChangGong-91 to get the various parameters such as velocity, height, control force, control surface deflection, 3 axis acceleration, 3 axis angular rate, pitch angle, angle of attack temperature and so on. We recorded the flight test data in VHS tapes and stored them to personal computer using A/D(analog to digital) converter. Flight test was done in various conditions, and the acquired data was processed with parameter identification method such as least square method. These data will be utilized for the development of Autopilot System design and Control Loading System design.

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A Study on the Coagulant Dosage Control in the Water Treatment Using Real Number Genetic-Fuzzy (실수형 유전-퍼지를 이용한 정수장 응집제주입제어에 관한 연구)

  • Kim, Yong-Yeol;Kang, E-Sok
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.3
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    • pp.312-319
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    • 2004
  • The optimum dosage control is presumably the goal of every water treatment plant. However it is difficult to determine the dosage rate of coagulant, due to nonlinearity, multivariables and slow response characteristics, etc. To deal with this difficulty, the real number genetic-fuzzy system was used in determining the dosage rate of the coagulant. The genetic algorithms are excellently robust in complex optimization problems. Since it uses randomized operators and searches for the best chromosome without auxiliary informations from a population which consists of codings of parameter set. To apply this algorithms, we made the real number rule table and membership function from the actual operation data of the water treatment plant. We determined optimum dosages of coagulant(LAS) using the fuzzy operation and compared them with the dosage rate of the actual operation data.