• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.544-549
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• 2001

The effect of power supply voltage on the performance limits in a laboratory Magneto-rheological fluid based device was identified by experiments. It suggests that the frequency range of motion for control be limited by the voltage attenuation due to the coil inductance and the maximum power supply voltage set for practical use of MRF devices. In this work, the magnetic and electrical characteristics of MRF device are investigated and a design procedure is formulated to achieve the desired performance for a given power supply.

• 한국정밀공학회지
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• 제15권4호
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• pp.83-90
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• 1998

In this paper, we present neural network for control of Left Ventricular Assist Device(LVAD) system with a pneumatically driven mock circulation system. Beat rate(BR), Systole-Diastole Rate(SDR) and flow rate are collected as the main variables of the LVAD system. System modeling is completed using the neural network with input variables(BR, SBR, their derivatives, actual flow) and output variable(actual flow). It is necessary to apply high perfomance control techniques, since the LVAD system represent nonlinear and time-varing characteristics. Fortunately. the neural network can be applied to control of a nonlinear dynamic system by learning capability In this study, we identify the LVAD system with neural network and control the LVAD system by PID controller and neural network feedforward controller. The ability and effectiveness of controlling the LVAD system using the proposed algorithm will be demonstrated by experiment.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.150-155
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• 1997

In this paper,we present neural network for control of Left Ventricular Assist Device(LVAD)system with a pneumatically driven mock cirulation system. It is necessary to apply high perfomance control techniques, since the LVAD system represent nonlinear and time-varing characteristics. Fortunately, the neural network can be applied to control of a nonliner dynamic system by learning capability. In this study,we identify the LVAD system with neural network and control the LVAD system by PID controller and neural network feedforward controller. The ability and effectiveness of controlling the LVAD system using the proposed algorithm will be demonstrated by computer simulation and experiment.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1668-1671
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• 2003

Today, remote monitoring and control systems are becoming the cost-effetive management tools for almost all water user groups, including irrigators, water districts, municipal water suppliers, and wildlife management groups. This paper represents a new approach in the water-gate control using radio communication. The proposed device is simple in structure and suitable for implementation of water-gate control through the transceiver by radio communication. It was confirmed that the developed device was very efficient to control water-gate and to prove the up and down motion of water-gate through the LCD displayer

• 제어로봇시스템학회논문지
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• 제10권6호
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• pp.566-573
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• 2004

This paper describes the ubiquitous home network (uHome-net) testbed and LonRF intelligent devices based on LonWorks technology. These devices consist of Neuron Chip, RF transceiver, sensor, and other peripheral components. Using LonRF devices, a home control network can be simplified and most devices can be operated on LonWorks control network. Also, Indoor Positioning System (IPS) that can serve various location based services was implemented in uHome-net. Smart Badge of IPS, that is a special LonRF device, can measure the 3D location of objects in the indoor environment. In the uHome-net testbed, remote control service, cooking help service, wireless remote metering service, baby monitoring service and security ＆ fire prevention service were realized. This research shows the vision of the ubiquitous home network that will be emerged in the near future.

• 대한전자공학회논문지
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• 제10권5호
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• pp.1-6
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• 1973

본논문은 자동급수기의 설계 및 제작연구를 한 것으로 digital scanning circuits를 이용하여 10개의 probe를 차례로 scanning하여 지표의 습도를 검출하여 reference level과 비교하여 필요한곳에 자동적으로 급수하도록 설계하였다. 이 system의 control을 위하여 main clock oscillator와 controloscillator를 사용하였고 control circuit로는 programmable unijunction transistor를 이용하여 reference level을 조절하게하여 임의의 원하는 습도에 급수하도록 하였다. 제작된 급수재는 모래의 습도가 6%에서 51%로 변화시키면서 실험하여 언제나 input level이 reference level보다 약 0.6V보다 높을때 완전동작하였으며 reference level은 임의로 조절할 수 있었다.

• 한국통신학회논문지
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• 제37A권10호
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• pp.885-894
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• 2012

최근 스마트 단말의 보급으로 데이터 트래픽에 대한 수요가 급증하고 있어 한정된 자원을 가진 기지국이 수용하기에는 많은 어려움이 따른다. 이러한 해결책으로 셀 또는 서로 인접한 셀 내의 단말들이 서로간에 기지국을 거치지 않고 디바이스간 직접적인 통신(D2D, Device-to-Device)을 통해 기지국의 과부하를 줄이고 주파수 부족 현상을 완화시킬 수 있는 방안이 제안되고 있다. 하지만 LTE-Advanced 시스템 내에서 셀룰러 링크와 무선 자원을 공유하는 D2D 링크는 자신이 속한 셀룰러 네트워크에 심각한 간섭을 줄 가능성이 높기 때문에 간섭을 제거하거나 완화시킬 필요가 있다. 따라서 본 논문에서는 셀룰러 링크와 D2D 링크가 자신의 간섭을 최소화하는 SFR(Soft Frequency Reuse) 기반 자원할당과 전송전력 조절 방법을 제안한다. 제안된 방법의 성능검증을 위해 시뮬레이션을 수행하였으며, 결과를 통하여 신호대 잡음비(SINR, Signal to Noise Ratio)와 시스템 평균 전송량(Throughput)에서 성능 이득을 가짐을 보였다.

• Archives of Pharmacal Research
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• 제16권3호
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• pp.227-230
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• 1993

A new device to detect methamphetamine (MA), amphetamine(A) and its metabolites in urine was developed using the paper strip method and the test tube method of dry chemical reagents. The reagent containing tetrabromophenolphthalein ethyl ester (TBPE) and borax. For the TBPE paper strip method, a device was prepared with a window at each end of the reagent paper strip ; one window is for the sample application, and the other window is for the methylene chloride. The diffused sample from one window reacts with reagent in the paper and produces color at the point where it meets with methylene chloride which has diffused form the other side. A positive smaple produces as red-purple color and the negative sample a greenish color, with a detection limit of 5-10 ppm. The result can be obtained within one minute. For the TBPE test tube method which contains dry reagents, the detection limit is 5 ppm and the result can be obtaineed within 30 seconds, however the carry-on is not as convenient as the paper strip method. The performance of both methods were evlauated by comparing with the results of gas chromatography (GC) and fluorescence polarizaiton immunoassay (FPIA). The results were proven that both methods were useful as primary screening reagents to detect MA in urine and in dry powder.

• 한국컴퓨터정보학회논문지
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• 제22권6호
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• pp.123-129
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• 2017

In this paper, we proposed a smart multiple-tap system which a remote user with smartphone can control multiple-taps in order to reduce standby-power consumption more conveniently when plugged-in electric appliances are turned-off. Recently, several researches of smart multiple-tap using IoT technology has reported. However, in these researches, an additional device like as a server computer is necessary, or multiple-taps could be only remotely controlled by smartphone and not directly controlled by on/off switch. The proposed smart multiple-tap system does not need any additional device only if it has a WiFi router, and it can be used for user as well as remote control using smartphone application and physically direct control using contact switches like existing multiple-taps. Our approach is to develop a smart multiple-tap device capable of WiFi communication can each serve as a server or a client, and can be operated by the hybrid switch combining the on/off contact switch and the relay switch. We implemented the prototype of the proposed system composed of the smart multiple-tap device and the smartphone application, and the test of the prototype validates the proposed system.

• 한국정보통신학회논문지
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• 제7권7호
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• pp.1483-1490
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• 2003

기존의 산업현장에서는 장비관리자가 장비의 모니터링과 제어를 위하여 항상 대기하고 있어야 한다. 이로 인하여 인력 낭비와 시간 손실이 많으므로 비효율적이다. 본 논문에서는 이러한 문제점을 해결하기 위하여 유무선 인터넷을 기반으로 하는 실시간 장비관리시스템을 개발한다. 이 시스템에서는 장비에 이상 발생 시 고장을 자동으로 감지하여 장비관리자의 휴대폰으로 통보하고, 관리자가 유무선 인터넷을 통하여 고장장비에 대한 응급조치를 한다. 이를 위하여 세부적으로 로컬 장비제어시스템, 장비관리시스템, 모바일 시스템, 웹 시스템을 각각 개발한다.