• Proceedings of the KSR Conference
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• 2003.10a
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• pp.138-143
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• 2003

KHST(Korean High-Speed Train, 350km/h), composed of 7 cars that are 2 power cars, 2 motorized car and 3 trailer cars, has been developed and is under on-line test. To verify hte design requirements about the functions and traction performances of this train, KRRI(Korea Railroad Research Institute) decided to evaluate traction performances of the train during on-line test. For this purpose, such as torque, velocity, voltage and current, must be measured. BRRI has developed the measurement system that can be measured vast and various signals effectively. In this paper, we introduce traction performances of KHST. The traction measurement items are focused on the verification of motor block performances.

• Journal of Animal Environmental Science
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• v.2 no.2
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• pp.111-116
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• 1996

An experiment was carried out to study the effect of environmental color on the eating behaviour in broiler chicks. A total of ninety broilers with average 350g of initial body weight were randomly assigned in the $3{\times}3$ randomized complete block design with 3 treatments(yellow, blue, red) and 10 birds per replication of various environmental color at walls, feeders and electric bulbs. The results obtained from these experiments are summarised as follows: 1. Feed Intake and average daily gain were significantly(P<0.05) increased by yellow colored environment. 2. Eating time and eating rate were significantly higher in the red colored than the other, indicating that yellow colored environment would maximize body weight gain and feed conversion for broiler chicks.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.245-248
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• 2008

This paper gives a description of the mode'ling and control of a single phase PWM(Pulse Width Modulation) converter for HEMU-400X(High-speed Electric Multiple Unit - 400 km/h experiment). The converter is part of a Auxiliary power unit supplied by the 25[kV], 60[Hz] overhead line. A model of the converter in a synchronously rotating reference frame of coordinates is used to develop a new type of control. The control system has separate controllers for the active and reactive current, permitting the free choice of the power factor. This paper proposes a new control method of PWM converter for Auxiliary power unit.

• Agricultural and Biosystems Engineering
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• v.4 no.1
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• pp.28-33
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• 2003

Achievements in the real-time soil spectro-photometer are: an improved soil penetrator to ensure a uniform soil surface under high speed conditions, real-time collecting of underground soil reflectance, getting underground soil color images, use of a RTK-GPS, and all units are arranged for compactness. With the soil spectrophotometer, field experiments were conducted in a 0.5 ha paddy field. With the original reflectance, averaging and multiple scatter correction, Kubelka-Munk (KM) transformation as soil absorption, its 1st and 2nd derivatives were calculated. When the spectra was highly correlated with the soil parameters, stepwise regression analysis was conducted. Results include the best prediction models for moisture, soil organic matter (SOM), nitrate nitrogen (NO$_3$-N), pH and electric conductivity (EC), and soil maps obtained by block kriging analysis.

• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.77-80
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• 1989

This paper describes a study on the locomotion control system for a indoor-use mobile wheelchair. Three lode of operations - BASIC, AUTOMATIC and PROGRAMMED - are employed as basic algorithm building block. One-chip microcomputer 8031 is dominating the control of actuation part and it can control the range of rotating speed of the wheel both right and left by servo motor. Keyboard is employed as a command input device. This system is intended to improve the daily life of the disabled by the intelligent interactive operation scheme.

• The Korean Journal of Pain
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• v.1 no.1
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• pp.3-8
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• 1988

Authors have experienced the treatment for the uppermost frequent cases, herpes zoster, frozen shoulder and low back pain among those who visited our pain clinic. 1. Herpes zoster The Patients who received the treatment within 4 weeks of the onset of the disease, not only healed herpes without leaving post herpetic neuralgia but also crust formation was fast. 2. Frozen shoulder Over 90% of the patients who received suprascapular nerve block accompanied with trigger points electric stimulation was very efficient procedure, futhermore, authors felt keenly the necessity each patients co-operation and individual endurance for this treatment. 3. Low back pain An epidural steroid administration to the patients who did not have any organic disturbances was effective treatment. If this non-effective, search other cause of the disease or operation was advisable one.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.900-907
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• 2008

All electric trains in the city should be run without any troubles of the equipments in order to offer good services to the passengers. But some breakdowns occur when they are operated due to the long time uses. There are mechanical troubles and electrical troubles included reactors. Most of them, the reason of the troubles can be found out easily after breakdown. But it is difficult to find out the reasons of the reactor troubles which disappear after operation. The reactors of the train filter the current which supplied from electrical lines and supply the current to the inverter and block the ripple of the current. Partial discharge occur from the reactor by the heat. accordingly, If the signals of discharge were perceived, it could be anticipate the deterioration degree of insulation. In this paper, on-monitoring system for reactor's troubles in trains is established and the output results of monitoring system are investigated.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.211-214
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• 2000

In this paper, a discrete-time S-dimensional chaos circuit (S = 1,2,3,4,...) with array structure is proposed. By employing array structure which consists of 1-dimensional chaos circuits, the proposed circuit can achieve long working-life. This feature is favorable to exploit as a building block of chaos application systems to get into home electric appliances. Further more, the proposed circuit synthesized using switched-current (SI) techniques is suitable for integration. Concerning the proposed circuit, SPICE simulations are performed. SPICE simulations showed that the proposed circuit can generate the chaotic signals in spite of the fault of the building blocks of the proposed circuit. The proposed circuit is integrable by a standard BiCMOS technology.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.3
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• pp.289-294
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• 1998

본 논문에서는 상태행렬과 입력행렬에 시변 불확실성이 있는 선형시스템에 대한 강인 추적 제어기를 제안한다. 본 논문에서 대상으로 하는 불확실성은 block-diagonally structured uncertainty와 norm bounded uncertainty인데 모두 정합 조건을 만족시킬 필요는 없다. 폐루프 시스템이 불확실성하에서 안정할 수 있는 조건을 제시하고 이 조건이 선형행렬 부등식으로 나타낼 수 있음을 보인다. 추적 오차를 줄이고 오차 감소 비율을 증가시킬 수 있는 최적화 방법도 제아한다. 또한 불확실성의 크기가 0으로 줄어들면 추적 오차도 0으로 줄어듬을 보인다.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.2
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• pp.46-52
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• 2004

Numerous connectors are used in automobiles for transmission of electrical signals across various electro-mechanical components. The connectors must operate with high reliability in order to minimize failures due to signal degradation. In this work, the effects of contamination at the contact interface of connectors used fur automobile crankshaft position sensor on the impedance change were investigated. An experimental set-up was built to simulate the electrical signal transmitted from the sensor to the engine control unit through a connector. Output from the connector was investigated using connectors contaminated with engine block residues and water droplets. It was found that slight contamination of the connectors could lead to significant signal degradation which can lead to engine failure. Also, the effect of water in the connector altered the signal severely. However, the signal gradually regained the original state as the water evaporated from the interface.