• Title/Summary/Keyword: internal control method

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Nonlinear Input-Output Feedback Linearizing Control for Power System Stabilization (전력계통 안정화를 위한 비선형 입출력 궤환 선형화 제어기)

  • Kim, Dong-Gun;Yoon, Tae-Woong
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.672-674
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    • 2004
  • Many nonlinear controllers for the power system are based on nonlinear models involving the power angle as an element of the state, and therefore the reference value for the power angle is needed. As this reference value is not generally available, it is difficult to apply such nonlinear control methods in practice. To deal with this problem, we present an input-output feedback linearizing control scheme by selecting the output as a combination of the squared voltage and the relative frequency. It is shown that the internal dynamics are locally stable with controllable damping, and that the frequency remains bounded for all time. Simulations illustrate the effectiveness of the proposed method.

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Orifice shape effect of the TLCD system under a low frequency (저주파수 하의 TLCD 시스템의 오리피스 형상 효과)

  • Lim, HeeChang
    • Journal of the Korean Society of Visualization
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    • v.12 no.1
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    • pp.30-34
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    • 2014
  • Bluff bodies under the external periodic force vibrate at their own natural or forced frequency. Rectangular bodies or similar structures such as high-rise towers and apartments, and recently a well-cited application - offshore floating bodies, usually needs to reduce these vibrations for stability and the mode control. Therefore, this study is aiming to reduce or control the vibration of a structure by a passive control method, i.e., TLCD (Tuned Liquid Column Damper). Controlling a moving body with a TLCD based on a variety of the orifice shape has been preliminary studied. In order to get a proper control, an optimized study is made on the design of the orifice shape, which has internal plates with the holes. The results show the force acting on the body due to the periodic movement highly depends on the number of holes on the plate and the height of the water level. Therefore, the optimum shape of the orifice and the height of the water level should be confirmed by a series of experiments.

Fault Detection of the Control System Based on Multiprocessors (다중 프로세서를 이용한 제어 시스템에서의 자체고장탐지)

  • ;;;;Zeung Nam Bien
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.8
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    • pp.906-915
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    • 1988
  • The reliability enhancement is the critical issue in many computer applications, particulary in process control system. In this paper we describe how to achieve the reliability improvement in control system which is based on multiprocessors. The proposed method is accomplished by using the techniques of fault detection which composed by internal and external fault detections, fault isolation for removing the fault propagation, safety action for driving safe input, and fault diagnosis. This approach is experimented and asopted in boiler backup control system constructed by VMEbus system, CPU boards, graphic system, and other interface boards with UNIX operating system.

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A Controller Design for Teleoperated Systems with Signal Transmission Time Delay

  • Ahn, Sung-Ho;Jin, Jae-Hyun;Park, Byung-Suk;Yoon, Ji-Sup
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.116.1-116
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    • 2002
  • When the teleoperated system has a signal transmission time delay between slave and control system , the system stability as well as the position tracking and the force reflecting performances are likely to be deteriorated. This paper proposed a bilateral control scheme and a controller design method for the teleoperated control systems with a signal transmission time delay. The proposed controller is a modified type of smith predictor for the time delay in each input and output stage of an open loop unstable plant. The proposed controller not only satisfies the system internal stability but also improves the position tracking performance with disturbance rejection capability. The simulation...

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QUANTITATION OF OXANDROLONE(A SYNTHETIC ANABOLIC STEROID) IN HUMAN URINE BY GC/MS

  • Park, Jongsei;Ohseung Kwon;Hea-Young P. Choo;Jawon Suh
    • Toxicological Research
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    • v.4 no.2
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    • pp.117-129
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    • 1988
  • A sensitive method for the quantitation of oxandrolone in urine was developed using GC/MS. After oral administration of 10mg oxandrolone, oxandrolone excreted in urine as unchanged form was extracted in ether and derivatized to its O-TMS. Oxandrolone excreted in urine as glucuronide conjugated form was extracted after enzymatic hydrolysis and derivatized to its O-TMS. The amounts of oxandrolone-O-TMS was measured in GC/MS with selected ion monitoring. Calusterone, a structurally similar anabolic steroid, was employed as internal standard.

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Experimental Studies of Neural Compensation Technique for a Fuzzy Controlled Inverted Pendulum System

  • Lee, Geun-Hyeong;Jung, Seul
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.1
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    • pp.43-48
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    • 2010
  • This article presents the experimental studies of controlling angle and position of the inverted pendulum system using neural network to compensate for errors caused due to fuzzy controller. Although fuzzy control method can deal with nonlinearities of the system, fixed fuzzy rules may not work and result in tracking errors in some cases. First, a nominal Takagi-Sugeno (TS) type fuzzy controller with fixed weights is used for controlling the inverted pendulum system. Then the neural network is added at the reference input to form the reference compensation technique (RCT)control structure. Neural network modifies the input trajectories to improve system performances by updating internal weights in on-line fashion. The back-propagation learning algorithm for neural network is derived and used to update weights. Control hardware of a DSP 6713 board to have real time control is implemented. Experimental results of controlling inverted pendulum system are conducted and performances are compared.

Determination of false positives in PCR diagnostics based on the internal transcribed spacer (ITS) of Gyrodactylus salaris using RFLP (RFLP를 이용한 Gyrodactylus salaris의 internal transcribed spacer(ITS) PCR 위양성 판별)

  • Min Seong Kim;Hee Jung Choi;Ji-Min Jeong;Mun-Gyeong Kwon;Seong Don Hwang
    • Journal of fish pathology
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    • v.37 no.1
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    • pp.147-153
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    • 2024
  • The World Organization for Animal Health (WOAH) recommends two protocols (ITS and COI) for conventional PCR of G. salaris diagnosis. However, ITS PCR protocol may yield false-positive results, leading to unnecessary countermeasures. It's difficult to distinguish between G. salaris and false-positive by similar amplicon size of PCR, since the amplicon size of ITS PCR in G. salaris and false-positive was 1,300 and 1,187 bp, respectively. The nucleotide sequences of ITS false-positive in rainbow trout is 99.7% identical to previously reported host genome sequences of rainbow trout (Oncorhynchus mykiss) and 95.3 to 89.1% identical to those of other salmonid fish species. To reduce false-positive PCR band, PCR was performed by the different annealing temperature, but PCR bands were still detected. In RFLP analysis by HaeIII, the PCR product of G. salaris was digested into four bands of 512, 399, 234 and 154 bp, while the false-positive was digested into seven bands of 297, 263, 242, 144, 93, 80 and 68 bp. In the RFLP patterns digested by HindIII, G. salaris showed two bands of 659 and 640 bp, while false-positive had one fragment of 1,187 bp without any digestion. Therefore, the RFLP method of ITS PCR with HaeIII and HindIII can be used for differentiation between G. salaris and false-positive. These results might provide important information on the improvement of PCR diagnostic method of G. salaris.

Quality Control Probes for Spot-Uniformity and Quantitative Analysis of Oligonucleotide Array

  • Jang, Hyun-Jung;Cho, Mong;Kim, Hyung-Hoi;Kim, Cheol-Min;Park, Hee-Kyung
    • Journal of Microbiology and Biotechnology
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    • v.19 no.7
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    • pp.658-665
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    • 2009
  • Quality control QC for spot-uniformity is a critical point in fabricating an oligonucleotide array, and quantification of targets is very important in array analysis. We developed two new types of QC probes as a means of confirming the quality of the uniformity of attached probes and the quantification of targets. We compared the signal intensities and fluorescent images of the QC and target-specific probes of arrays containing only target-specific probes and those containing both QC and target-specific probes. In a comparison of quality control methods, it was found that the arrays containing QC probes could check spot-uniformity or spot defects during all processes of array fabrication, including after spotting, after washing, and after hybridization. In a comparison of quantification results, the array fabricated by the method using QC probes showed linear and regular results because it was possible to normalize variations in spot size and morphology and amount of attached probe. This method could avoid errors originating in probe concentration and spot morphology because it could be normalized by QC probes. There were significant differences in the signal intensities of all mixtures (P<0.05). This result indicates that the method using QC probes is more useful than the ordinary method for quantification of mixed target. In the quantification of mixed targets, this method could determine a range for mixed targets of various amounts. Our results suggest that methods using QC probes for array fabrication are very useful to the quality control of spots in the fabrication processes of quantitative oligonucleotide arrays.

Traditional Korean Medicine for Non-Small Cell Lung Cancer Patient Undergoing Pembrolizumab Immunotherapy: A Case Report (Pembrolizumab 면역치료를 시행 중인 비소세포성 폐암환자의 한방치료 증례보고)

  • Shim, So-hyun;Seo, Hee-jeong;Seo, Hyung-bum;Cho, Im-hak;Lee, Chan;Kim, So-yeon;Han, Chang-woo;Park, Seong-ha;Yun, Young-ju;Lee, In;Kwon, Jung-nam;Hong, Jin-woo;Choi, Jun-yong
    • The Journal of Internal Korean Medicine
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    • v.40 no.4
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    • pp.709-722
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    • 2019
  • Objective: The purpose of this study was to report the effect of traditional Korean medicine (TKM) in alleviating the side effects of lung cancer patient undergoing immunotherapy. Method: A 43-year-old man, who was diagnosed with non-small cell lung cancer, received pembrolizumab treatments. The patient was treated with acupuncture and herbal medicine (Geoeoyangpye-tang) to control various uncomfortable symptoms. The degree of pain was measured by the numeric rating scale (NRS). The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Core 30 (EORTC QLQ-C30) and the EORTC 13-item lung cancer-specific module (EORTC LC-13 questionnaire) were used to assess the change in the quality of life. Results: After the TKM treatment, the flank pain and arthralgia based on the NRS were significantly improved. Various uncomfortable symptoms such as fatigue, dyspnea, insomnia, and loss of appetite were also significantly improved, based on the EORTC QLQ-C30 and EORTC QLQ-LC13. The size of the primary tumor was decreased during treatment. The disease status was stable radiologically after two months from discharge.

Development of simulation-based testing environment for safety-critical software

  • Lee, Sang Hun;Lee, Seung Jun;Park, Jinkyun;Lee, Eun-chan;Kang, Hyun Gook
    • Nuclear Engineering and Technology
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    • v.50 no.4
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    • pp.570-581
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    • 2018
  • Recently, a software program has been used in nuclear power plants (NPPs) to digitalize many instrumentation and control systems. To guarantee NPP safety, the reliability of the software used in safetycritical instrumentation and control systems must be quantified and verified with proper test cases and test environment. In this study, a software testing method using a simulation-based software test bed is proposed. The test bed is developed by emulating the microprocessor architecture of the programmable logic controller used in NPP safety-critical applications and capturing its behavior at each machine instruction. The effectiveness of the proposed method is demonstrated via a case study. To represent the possible states of software input and the internal variables that contribute to generating a dedicated safety signal, the software test cases are developed in consideration of the digital characteristics of the target system and the plant dynamics. The method provides a practical way to conduct exhaustive software testing, which can prove the software to be error free and minimize the uncertainty in software reliability quantification. Compared with existing testing methods, it can effectively reduce the software testing effort by emulating the programmable logic controller behavior at the machine level.