• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1996년도 추계학술대회 논문
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• pp.133-137
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• 1996

This paper presents a new approach to the design of neural control system using digital signal processors in order to improve the precision and robustness. Robotic manipulators have bevome increasingly important in the field of flexible automation. High speed and high-precision trajectory tracking arre indispensable capabilities for their versatile application. the need to meet demanding control requirement in increasingly complex dynamical control systems under sygnificant uncertainties leads toward design of implementing real time neural control to provide an enhanced motion control for robotic manipulators. In this control scheme the ntworks intrduced are neural nets with dynamic neurouns whose dynamics are distributed over all the network nodes. The nets are trained by the distributed dynamic are distributed over all the network nodes. The nets are trained by the distributed dynamic back propagation algorithm. The proposed neural network control scheme is simple in structure fast in computation and suitable for implementation of real-time control, Performance of the neural controller is illustrated by simulation and experimental results for a SCAEA robot.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.242-248
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• 1987

Recently, a quite large number of investigation is published on the subject of Flexible Manufacturing System which can cope with the volatile market demand and the variety of product. Minimum requirement of designing FMS is depicted and by investigating the communication system between the machine tool and the cell control computer, ana between the central computer and the cell control computer, when it is formed as a sub-system of an FEM, the software can be evolved to the control software of the total Flexible Manufacturing System. It is developed the communication system between the central computer and the cell control computer which is the basic structure of the control architecture of FMS under the concept of DNC (Direct Numerical Control). It is used CYBER 180-830 as the central computer, and GMC-1100 computer as the cell control computer, and the main basic program is developed and tested, thus forming a DNC system which can be used in educational environment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2445-2447
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• 2002

In this paper, CAN-based feedback control system is proposed for the pressurization system of korean high-speed train. The control performance of the system is evaluated. According to the requirement of the pressurization system A process model considering network delay and an adaptive PID control method based on the process model are proposed here. And it is shown that the proposed adaptive PID control method considering the network delay has on adequate feature compared to some other existing methods consequently it can be considered to be applied the pressurization system of korean high-speed train.

• 설비공학논문집
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• 제14권11호
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• pp.948-953
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• 2002

The electronic expansion valve (EEV) may be used to control the refrigerant flow rate for the multi-type heat pump. Stepping motor driven EEV may precisely control the refrigerant flow rate to meet each internal load requirement. To control the EEV, PI algorithm may be used. But the hysteresis of EEV deteriorates the performance of superheat control. To reduce the performance degradation, the PI algorithm along with the dither signal may be used. The dither signal, with about 10 times higher frequency than the system crossover frequency and about 10 times larger magnitude than the deadband of hysteresis, was selected for the superheat control of EEV. Experimental results showed the improvement of EEV control by adding the dither signal to the PI algorithm.

• 제어로봇시스템학회논문지
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• 제17권1호
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• pp.47-53
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• 2011

To enable the efficient operation of ITS, it is necessary to collect location data for vehicles on the road. In the case of futuristic transportation systems like ubiquitous transportation and smart highway, a method of data collection that is advanced enough to incorporate road lane recognition is required. To meet this requirement, technology based on radio frequency identification (RFID) has been researched. However, RFID may fail to yield accurate location information during high-speed driving because of the time required for communication between the tag and the reader. Moreover, installing tags across all roads necessarily incurs an enormous cost. One cost-saving alternative currently being researched is to utilize GNSS (global navigation satellite system) carrierbased location information where available. For lane recognition using GNSS, a precise digital map for determining vehicle position by lane is needed in addition to the carrier-based GNSS location data. A "precise digital map" is a map containing the location information of each road lane to enable lane recognition. At present, precise digital maps are being created for lane recognition experiments by measuring the lanes in the test area. However, such work is being carried out through comparison with vehicle driving information, without definitions being established for detailed performance specifications. Therefore, this study analyzes the performance requirements of a precise digital map capable of lane recognition based on the accuracy of GNSS location information and the accuracy of the precise digital map. To analyze the performance of the precise digital map, simulations are carried out. The results show that to have high performance of this system, we need under 0.5m accuracy of the precise digital map.

• 한국전자파학회논문지
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• 제14권6호
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• pp.630-637
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• 2003

WCDMA 시스템에서 주파수 오차에 의한 단말기 성능 영향을 분석하기 위해 기지국과 이동 단말기 사이의 주파수 오차 발생 원인을 고찰한 후 단말기 수신부에서 주파수 오차를 정정하기 위한 자동 주파수 오차 보상방법을 소개하였다. 시스템 요구 규격 중 자동 주파수 오차 보상 동작에 관련된 성능요구 조건들을 바탕으로 여 기지국과 단말기간 연동시험을 수행하였고 주파수 오차보상 후 단말기 송신 주파수에서 4 Hz의 주파수 차를 얻음으로써 시스템에서 요구하는 주파수 오차 허용량인 $\pm$ 0.1 ppm($\pm$200 Hz)이내의 규격을 만족함을 보였다. 주파수 오차에 의한 송신성능 열화를 에러벡터 크기(EVM) 값으로 확인하였으며 또한 수신 성능 열화를 Ec/Io로 측정하였고, 주파수 오차조정의 정확성을 개선시키기 위한 모뎀 제어신호와 RF 간 인터페이스 관계를 제시하였다.

• 한국건설관리학회논문집
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• 제3권4호
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• pp.114-122
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• 2002

EVMS(Earned Value Management System)는 최근 건설 프로젝트를 관리하는데 매우 유용한 도구로 인식되고 있으며, 정부차원에서 적극적으로 도입을 검토하고 있는 선진 관리기법이다. 이 EVMS는 미국방성에 의해 1960년대부터 프로젝트의 효율적인 관리를 위해 개발된 C/SCSC(Cost/schedule Control System Criteria)에 기반을 두고 있으며, 국내외에서 정부발주공사뿐만 아니라 민간발주의 건설프로젝트를 관리하는 도구로 활용하기 위해 연구가 활발하게 진행되고 있다. 본 연구에서는 공정관리 프로그램과 복합작업모델(Work Package Model)을 바탕으로 건설프로젝트의 EV계획단계의 관리계정계획(CAP)을 수립하는데 효과적으로 사용할 수 있는 방안을 제조업의 재고관리모형중의 한 형태로 조립제품의 자원운영계획을 수립하는데 우수한 기법으로 알려진 MRP(Material Requirement Planning)기법을 활용하여 제시하고자 한다.

• 한국정보통신학회논문지
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• 제7권2호
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• pp.214-227
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• 2003

어플리케이션을 개발하는 데 있어서 전통적인 텍스트 기반의 방법으로는 정확한 요구사항을 파악하기 어렵다. 그리고 각 개발 단계에서의 분석과 확인에 관한 문제점이 있다. 그러므로 만약 검증에서 에러와 요구사항의 교환이 요구된다면 모든 시스템에 나쁜 효력이 발생할 수 있다. 이 경우 개발비용과 기간에 불리하게 작용한다. 따라서 분석과 검증은 에러가 자주 일어나는 것을 방지하기 위해서 수행한다. 본 논문에서는 각 개발 단계에 대한 분석과 확인 그리고 그래픽 인터페이스를 제공하는 SDL을 이용한 TCP/IP 혼잡제어 알고리즘에 대해서 논한다. SDL을 사용함으로써 각 개발 단계에 대한 명확한 표현과 정확한 에러 또는 요구사항 교환에 검증을 쉽게 할 수 있다. 추가적으로 프로토콜의 단계는 MSC의 확인을 통해서 시뮬레이션으로 확인하고 결론에서는 TCP/IP 프로토콜보다 개발의 가능성을 보인다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권5호
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• pp.647-653
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• 2015

A 12-wk feeding trial was conducted to evaluate the essentiality of choline supplementation in diets for parrot fish. Five isonitrogenous and isocaloric diets were supplemented with 0 (as control), 500, 1,000, and 2,000 mg choline per kg diet, and a positive control diet without choline contained 0.3% of 2-amino-2-methyl-1-propanol as choline biosynthesis inhibitor (designated as Con, C500, C1000, C2000 and $Con^+$, respectively). Triplicate groups of fish (body weight, $8.8{\pm}0.01g$) were fed one of the experimental diets at a rate of 4% body weight twice daily. The fish fed $Con^+$ diet revealed significantly lower growth performance and feed utilization efficiency than other fish groups. Supplementation of choline to the basal diet did not significantly influence fish growth. The highest liver lipid content was observed in fish fed the $Con^+$ diet and inversely correlated with liver choline concentration although the differences were not significant. Also, significantly higher liver linoleic, eicosapentaenoic and docosahexaenoic acid contents were found in fish fed the $Con^+$ diet. Innate immune parameters including respiratory burst and myeloperoxidase activities were not significantly affected by dietary choline levels. The findings in this study conclude that choline concentration of approximately $230mgkg^{-1}$ diet meets the requirement of parrot fish.

• 한국자동차공학회논문집
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• 제7권9호
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• pp.1-9
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• 1999

Liquid Petroleum Gas (LPG) has been widely used for commercial light-duty vehicles worldwide. Since LPG has a higher octane number and a lower maximum combustion temperature than gasoline , it becomes more popular fuel for reducing exhaust emissions. In tihs study, mathematical models of air intake and fuel delivery system are presented, and a PI-controller is designed for air-fuel ratio control. Hardware and software of an engine control module (ECM) are designed for an LPG engine. The ECM is built using a Motorola MC68HC05. In order to control the air-fuel ratio at stoichiometry, the PI-control algorithm is implemented in the ECM. The experiment results show the proto LPG ECM and its control scheme perform well to meet the stoichiometric air-duel ratio requirement.