• Title/Summary/Keyword: Computer controlled system

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Laserthermia Induced Histological Changes in Different Thermal Condition (Laser Hyperthermia에서 조건변동에 따른 병소변화)

  • Kim, Sang-Woo;Lee, Kyung-Yup;Kim, Seong-Ho;Bae, Jang-Ho;Kim, Oh-Lyong;Choi, Byung-Yearn;Cho, Soo-Ho;Shin, Hyun-Jin;Lee, Jun-Ha
    • Journal of Yeungnam Medical Science
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    • v.12 no.2
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    • pp.331-338
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    • 1995
  • Laserthermia is a new method of local hyperthermia using fiber optic guided probe with computer controlled Nd-YAG laser system. We used a synthetic sapphire probe and allowed irradiation with contolled low power laser energy (less than 5W), in different thermal condition (temprature: 38.5~50 degrees C) for 10 minutes, in the normal brain tissue of 18 rabbits. In results, the histological changes of brain tissue was variable (myelin condensation, chromatin condensation, nuclear waving and palisading, RBC discoloration, cell necrosis) in microscopic findings after laser irradiation, but changing area was not occured proportionally in thermal condition level. Cell necrosis appears to over 44.5 degrees C and the distance was about 1.25 mm. This study, using computer controlled laserthermia system for interstitial local hyperthermia, may offer many advantages in the experimental treatment and clinical management of tumor. Minimizing normal tissue damage is now being developed.

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Design and Implementation of Web-based Learning System by Applying Computer Adaptive Testing (CAT) (CAT 이론을 응용한 Web-based 교수학습 시스템 개발)

  • Park, Jin-Hui;Ha, Tae-Hyeon
    • Journal of Digital Convergence
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    • v.4 no.1
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    • pp.43-54
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    • 2006
  • New technologies have turned theories of education engineering into practice and also made education more efficient. One of them is the theory of 'Computer Adaptive Testing(CAT)'. This study is aimed to design and develop a web-based teaming system by making up for the weak points in the existing computer adaptive testing(CAT). The characteristics of the system are as follows: Firstly, tests can be controlled to fit the teachers' purposes by putting in different levels of both questions and samples. Secondly, this system does not test the same number of questions as students with different levels of ability do on a paper test, but a test can be taken according to their level. Thus this system is able to correctly judge learners' ability in a short time.

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Electric Therapy System Based on Discontinuous Conduction Mode Boost Circuit

  • Chen, Wenhui;Lee, Hyesoo;Jung, Heokyung
    • Journal of information and communication convergence engineering
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    • v.18 no.4
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    • pp.245-253
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    • 2020
  • The human body and nervous system transmit information through electric charges. After the electric charge transmits information to the brain, we can feel pain, numbness, comfort, and other feelings. Electric therapy is currently used widely in clinical practice because the field of examination is more representative of electrocardiogram, and in the field of treatment is more representative of electrotherapy. In this study, we design a system for neurophysiological therapy and conduct parameter calculation and model selection for the components of the system. The system is based on a discontinuous conduction mode (DCM) boost circuit, and controlled and regulated by a single-chip microcomputer. The system does not only have a low cost but also fully considers the safety of use, convenience of the human-computer interface, adjustment sensitivity, and waveform diversity in the design. In future, it will have strong implications in the field of electrotherapy.

A Design and Implementation of Multiple RobotCar System based on Mobile (기반 다중 로봇카 시스템 설계 및 구현)

  • Choi, Yue-soon;Joung, Suck-tae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.10
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    • pp.2315-2320
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    • 2015
  • The robot has a smart function with the development of mobile devices and provides safety and convenience to our lives. In this paper, we study multiple robotcar system based on mobile that can be controlled by remote control. Robotcar with arduino can be controlled from server, but it also designed to be controlled by mobile devices as controller's necessary. Besides, it have feature that many robotcars can be controlled at the same time by using several mobile devices which select each robotcar.

A Miniature Inertia Simulator using Vector Controlled Induction Motor (벡터제어 유도전동기를 이용한 축소형 관성 시뮬레이터)

  • 김길동;박현준;한영재;한경희;조정민
    • The Transactions of the Korean Institute of Power Electronics
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    • v.7 no.1
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    • pp.74-80
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    • 2002
  • A propulsion system apparatus for railroad vehicle is estimated it's performance because of safety and confidence. In general, flywheel type testing method is widely used in the equipment. However, mechanical inertia generated by the flywheel can not be varied (or controlled) and can not be represent actual running resistance. In this study, we have focused on the development of variable vehicle load generation. Therefore, we have proposed the method which uses variable vehicle load controlled by vector motor to get the characteristics of the real vehicle load and confirmed the results with those of computer simulations.

Study on Attitude Control System of Rotary Implement Attached on Agricultural Tractor (트랙터 로타리 작업기용 자세 제어 시스템에 관한 연구)

  • Lee, J.Y.;Go, W.;Shim, J.S.;Shin, H.C.
    • Journal of Biosystems Engineering
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    • v.23 no.5
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    • pp.427-438
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    • 1998
  • In Korea, rotary implements are mainly utilized in the tillage operation. The attitude control system for rolling phenominon of tractors, which in caused due to uneven ground surfaces and sinkage of tractor wheels, is one of the most important control systems in agricultural tractors. The attitude control system of a rotary implement, attached on tractors, was designed and fabricated in this study. The control system was largely composed of four main units; a setting unit, a detection unit, a controller and a hydraulic unit. The implement was controlled by control signals from a computer proportional to controlled errors, on/off action of two directional solenoide valve and lift cylinder on the right lift rod. Response characteristic experiments for the control system fabricated in this study were carried out indoors and outdoors. The results of experiments showed the response characteristics sufficient to use as the attitude control system of rotary implements for agricultural tractors.

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Pitch Angle Control and Wind Speed Prediction Method Using Inverse Input-Output Relation of a Wind Generation System

  • Hyun, Seung Ho;Wang, Jialong
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.1040-1048
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    • 2013
  • In this paper, a sensorless pitch angle control method for a wind generation system is suggested. One-step-ahead prediction control law is adopted to control the pitch angle of a wind turbine in order for electric output power to track target values. And it is shown that this control scheme using the inverse dynamics of the controlled system enables us to predict current wind speed without an anemometer, to a considerable precision. The inverse input-output of the controlled system is realized by use of an artificial neural network. The proposed control and wind speed prediction method is applied to a Double-Feed Induction Generation system connected to a simple power system through computer simulation to show its effectiveness. The simulation results demonstrate that the suggested method shows better control performances with less control efforts than a conventional Proportional-Integral controller.

PC Based Distributed Control System of AGV with Multi-Thread Method (다중 쓰레드 기법을 미용한 AGV의 PC기반 분산제어 시스템)

  • Jun, Sung-Jae;Cho, Yon-Sang;Park, Heung-Sik
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.9 s.174
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    • pp.107-114
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    • 2005
  • With the recent progress in flexible manufacturing systems (FMS) in industry, increasing attention has been given to Automatic Guided Vehicle (AGV) systems. An AGV is a self-powered unit for transporting materials between stations without needing to be controlled by an operator. Such a system has several sensors to recognize the external state, and it is designed to travel between stations automatically without external assistance. To manage each device automatically in real time it requires a distributed controller with a main computer as the host, as well as a number of micro-controllers. In this study, an AGV system with dual motor drive was constructed. A Pentium 4 personal computer was set up as the main host for the distributed control, and this communicated with other micro-controllers in the management of the motor. The speed of each motor was also controlled by a micro-controller.

Data-based Stability Analysis for MIMO Linear Time-invariant Discrete-time Systems

  • Park, Un-Sik;Ikeda, Masao
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.680-684
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    • 2005
  • This paper presents a data-based stability analysis of a MIMO linear time-invariant discrete-time system, as an extension of the previous results for a SISO system. In the MIMO case, a similar discussion as in the case of a SISO system is also applied, except that an augmented input and output space is considered whose dimension is determined in relation to both the orders of the input and output vectors and the numbers of inputs and outputs. As certain subspaces of the input and output space, both output data space and closed-loop data space are defined, which contain all the behaviors of a system, respectively, with zero input in open-loop and with a control input in closed-loop. Then, we can derive the data-based stability conditions, in which the open-loop stability can be checked by using a data matrix whose column vectors span the output data space and the closed-loop stability can also be checked by using a data matrix whose column vectors span the closed-loop data space.

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The Performance Analysis of a DS/CDMA Cellular System using an Adaptive Array Antenna in Shadowing (전파음영 환경에서 적응 어레이 안테나를 적용한 DS/CDMA 셀룰라 시스템의 성능 분석)

  • Kim, Hyoung-Chae;Kim, Hang-Rae;Kim, Nam
    • Proceedings of the IEEK Conference
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    • 2000.11a
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    • pp.149-152
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    • 2000
  • In this paper, the reverse link performance of an imperfect power controlled DS/CDMA cellular system that uses a base station array antenna which can effectively remove the multiple access interference is analyzed considering both beam forming algorithm and power control error in shadowing. The blocking probability of the DS/CDMA cellular system based on array parameters, Eb/No and statistics of interference is derived, and then the system capacity corresponding to a certain blocking probability is calculated. On the assumption that the blocking probability is set 1 %, the system capacity using MCGM algorithm with 12 antenna arrays is increased about 59 % than that using 8 antenna arrays when power control error is 2.5 ㏈.

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