• Title/Summary/Keyword: adaptive timing control

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A Study on Spark Advance Control System using Microprocessor (마이크로프로세서를 이용한 엔진점화시기 제어장치)

  • Min, Y.B.;Lee, K.M.;Lee, S.K.;Kim, Y.H.
    • Journal of Biosystems Engineering
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    • v.14 no.2
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    • pp.80-84
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    • 1989
  • In order to improve the combustion efficiency of the agricultural engine, an ignition timing control system was developed and tested. The control system was composed of the CDI ignition circuit, the microcomputer and the interfacing devices. In this study, the simplicity of the control system and the flexibility of the control strategy were emphasized for the precision, the applicability and the economical efficiency. The hardware was consisted in almost the same compositions as those of the automobile engine. The softwares of the control algorithms were developed to three types depending on the combination of the quasi-adaptive control and the open loop control which had the different spark advance equations according to the input variables such as engine speed, exhaust gas temperature and brake torque. The test results were summarized as follows: 1. By using the computer control system, the fuel consumption efficiency could be improved and the fuel consumption could be reduced by 0 to 57% compared to that of the fixed spark advance system. 2. The fuel consumption of the control mode with the quasi-adaptive algorithm was reduced by average 0.8% compared to that of the control mode without quasi-adaptive algorithm. 3. It was found that the control mode with the quasi-adaptive algorithm adopting single input of engine speed had most applicability and economical efficiency among three types of the control algorithms.

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An all-digial HDTV modem for terrestrial broadcasting (지상 방송용 고선명 텔레비젼을 위한 전 디지탈 모뎀)

  • 한동석;신현수;최양석;송동일
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.7
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    • pp.1777-1786
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    • 1996
  • This paper describes theories and implementation techniques of a digital high-definition television(HDTV) modem based on 32-QAM for terrestrial broadcasting. We proposed a digital demodulation scheme and a symbol timing recovery structure based on the band edge component maximization(BECM) method. The adaptive equalizer has 256 complex taps to remove the multipath of delays ranging from -2.mu.s~+24.mu.s with a new T/2-spaced blind equalization algorithm. computer simulation results reveal that the proposed algorithm outperforms other conventional blind equalization algorithm a digital HDTV modem with 4.91MHz symobol rate is implemented by utilizing the proposed algorithms. All processings for modem operations such as demodulation, estimation of symbol timing phase error, adaptive equalization, and carrier recovery except IF signal processing and sampling phase control part of the AD converter are done in digital domain. Especially, the carrier recovery loop can track a carrier offset of upto .+-.350KHz.

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The Assessment of TRACS(Traffic Adaptive Control System) (교통대응 신호제어 시스템의 효율성 평가)

  • 이영인
    • Journal of Korean Society of Transportation
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    • v.13 no.1
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    • pp.5-33
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    • 1995
  • This paper addresses the outlines of the traffic signal timing principles engaged in TRACS and the results of field test. Research team, encompassing research institute, university, and electronic company, conducted the three-year project for developing the new system, named TRACS(Traffic Adaptive Control System). The project was successfully completed in 1994. TRACS aims at accomplishing the objectives of better traffic adaptability and more reliable travel time prediction. TRACS operates in real-time adjusting signal timings throughout the system in response to variations in traffic demand and system capacity. The purpose of TRACS is to control traffic on an area basis rather than on an isolated intersection basis. An other purpose of TRACS is to provide real-time road traffic information such as volume, speed, delay , travel time, and so on. The performance of the first version of TRACS was compared to the conventional TOD control through field test. The test result was promi ing in that TRACS consistantly outperformed the conventional control method. The change of signaltiming reacted timely to the variation of traffic demand. Extensive operational test of TRACS will be conducted this year, and some functions will be enhanced.

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Memory Controller Architecture with Adaptive Interconnection Delay Estimation for High Speed Memory (고속 메모리의 전송선 지연시간을 적응적으로 반영하는 메모리 제어기 구조)

  • Lee, Chanho;Koo, Kyochul
    • Journal of IKEEE
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    • v.17 no.2
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    • pp.168-175
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    • 2013
  • The delay times due to the propagating of data on PCB depend on the shape and length of interconnection lines when memory controllers and high speed memories are soldered on the PCB. The dependency on the placement and routing on the PCB requires redesign of I/O logic or reconfiguration of the memory controller after the delay time is measured if the controller is programmable. In this paper, we propose architecture of configuring logic for the delay time estimation by writing and reading test patterns while initializing the memories. The configuration logic writes test patterns to the memory and reads them by changing timing until the correct patterns are read. The timing information is stored and the configuration logic configures the memory controller at the end of initialization. The proposed method enables easy design of systems using PCB by solving the problem of the mismatching caused by the variation of placement and routing of components including memories and memory controllers. The proposed method can be applied to high speed SRAM, DRAM, and flash memory.

Biological Rhythms and Food Intake (생체 리듬과 음식 섭취)

  • Lee, Young-Ho
    • Sleep Medicine and Psychophysiology
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    • v.5 no.1
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    • pp.34-44
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    • 1998
  • Living organisms are influenced by many external rhythms and they have adapted their physiology to periodically changing conditions. These adaptive strategies are controlled by endogenous innate programs of behavior and physiology which are determined by external signals ("Zeitgeber"). There are many biological rhythms, each with its own characteristic functional adaptation. Among them, the presence of endogenous time control of feeding and drinking becomes obvious. There are increasing evidences that the control of food intake, food selection, and drinking are regulated by the endogenous rhythms including a circadian rhythm. However, there have been many restrictions in understanding the endogenous control of food intake itself and its mechanism. To broaden our know ledges of the endogenous time control of feeding and drinking, the author reviwed the characteristics of the endogenous timing for food intake, the influence of circadian pacemakers and food-entrainable oscillators, the interaction between the circadian control and the external and internal conditions in the control of food intake, the conseqences of feeding, the circadian control of food selection, and the biological cycles in energy balance.

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An Efficient Node Life-Time Management of Adaptive Time Interval Clustering Control in Ad-hoc Networks (애드혹 네트워크에서 적응적 시간관리 기법을 이용한 클러스터링 노드 에너지 수명의 효율적인 관리 방법)

  • Oh, Young-Jun;Lee, Knag-Whan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.2
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    • pp.495-502
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    • 2013
  • In the mobile Ad hoc Network(MANET), improving technique for management and control of topology is recognized as an important part of the next generation network. In this paper, we proposed an efficient node life time management of ATICC(Adaptive Time Interval Clustering Control) in Ad-hoc Networks. Ad-hoc Network is a self-configuration network or wireless multi-hop network based on inference topology. This is a method of path routing management node for increasing the network life time through the periodical route alternation. The proposed ATICC algorithm is time interval control technique depended on the use of the battery energy while node management considering the attribute of node and network routing. This can reduce the network traffic of nodes consume energy cost effectively. As a result, it could be improving the network life time by using timing control method in ad-hoc networks.

An efficient Clustering Node Life Time management Technique in MANET algorithm (MANET에서 클러스터링 노드의 효율적인 수명 관리 기법)

  • Lee, Jong-Seung;Kim, Yeong-Sam;Oh, Young-Jun;Lee, Kang-Whan
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.05a
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    • pp.746-748
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    • 2011
  • MANET(Mobile Ad-hoc Network) is a self-configuration network or wireless multi-hop network based on inference topology. The proposed ATICC(Adaptive Time Interval Clustering Control) algorithm for hierarchical cluster based MANET. The proposed ATICC algorithm is time interval control technique for node management considering the attribute of node and network traffic. ATICC could be made low the network traffic. Also it could be improving the network life time by using timing control method.

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Design of an Adaptive and Robust Timing Control Protocol in WSNs (WSNs에서 견고한 적응형 시간 제어 프로토콜 설계)

  • Park, Jae-Bok;Kim, Hyun-Tae;Cho, Gi-Hwan
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.1356-1358
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    • 2007
  • 데이터 병합은 무선 센서 네트워크에서 발생하는 통신량 축소로 에너지 소비의 최소화를 달성하기 위해 적용되는 기법이다. 이런 데이터 병합의 시간 제어는 종단간 지연시간을 최적화하면서 병합 시간의 적응적인 조절로 WSNs의 성능을 크게 향상시킬 수 있다. 따라서 본 논문은 WSNs에서 데이터 정확성과 종단간 지연시간 사이에 발생하는 상충조건의 최적화를 위해 무선 손실을 고려한 적응성 있는 타이밍 제어 프로토콜을 설계하였다. 이 프로토콜은 무선 손실의 변화에 적응성을 있는 데이터 병합을 수행할 수 있도록 선택적 참여율과 중요도를 결정함으로써 네트워크 전체에 패킷 전송 횟수를 균등하게 분배하여 전체 네트워크 안정성을 높일 수 있도록 하였다.

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Design of a CMOS Programmable Slew Rate Operational Amplifier with a Switched Parallel Current Subtraction Circuit (병렬전류감산기를 이용한 슬루율 가변 연산증폭기 설계)

  • 신종민;윤광섭
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.5
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    • pp.730-736
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    • 1995
  • This paper presents the design of a CMOS programmable slew rate operational amplifier based upon a newly proposed concept, that is a switched parallel current subtraction circuit with adaptive biasing technique. By utilizing the newly designed circuit, it was proven that slew rate was linearly controlled and power dissipation was optimized. If the programmable slew rate amplifier is employed into mixed signal system, it can furnish the convenience of timing control and optimized power dissipation. Simulated data showed the slew rate ranging from 5. 83V/$\mu$s to 41.4V/$\mu$s, power dissipation ranging from 1.13mW to 4.1mW, and the other circuit performance parameters were proven to be comparable with those of a conventional operational amplifier.

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A Comparison Study of Different Offset Transition Lengths in Simulation Environment (모의실험 환경에서의 옵셋전이길이 비교연구)

  • Kim, Jin-Tae;Chang, Myung-Soon;Park, Jae-Wan
    • Journal of Korean Society of Transportation
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    • v.23 no.7 s.85
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    • pp.43-52
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    • 2005
  • Signal timing transition has recently been highlighted with Adaptive Traffic Control Systems (ATCS) providing advanced traffic signal operation including real-time grouping of coordinated intersections. Signal timing transition occurs when such signal timings as cycles and offsets are changed at coordinated intersections. Setting a proper length of signal timing transition has become in interest for real-time coordination. This paper presents a study verifying the effects of different lengths of signal timing transition. Four different transition lengths were tested and compared in simulation environment. They include a single, double, treble, quadruple cycle length transitions. The number of cycles represents the ones used (interpolation) for transition. Signal timings were controlled to be adjusted uniformly and discretely during a transition period. Transition times considered in the test are within ranges of ${\pm}20$ percents of cycle lengths. It was found from the study that a single cycle transition performs better than or at least equal to the ones from the other with fifteen different operational conditions, which are developed based on a hypothetical arterial. It was suggested that a single cycle length transition be beneficial when amount of transition is within ${\pm}20$ percents of cycle lengths.