• 전자공학회논문지SC
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• 제46권3호
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• pp.8-14
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• 2009

본 논문은 성능 향상을 위하여 IMC 제어 구조를 갖는 PID 제어기 설계를 제안했다. 내부 모델은 최종값 정리와 유전자 알고리즘을 이용하여 2차의 지연시간을 갖는 모델로 동정 하였다. 그리고 제어기 파라미터 값은 성능지수 (IAE, ITAE)값이 최소가 되도록 내부 모델과 수치적 계산에 의해서 자동 동조된다. 시뮬레이션을 통하여 다양한 공정에 대하여 본 논문에서 새롭게 제안된 방법이 기존의 방법보다 우수함을 확인 할 수 있었다.

• 대한전기학회논문지:전력기술부문A
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• 제49권3호
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• pp.95-106
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• 2000

The load frequency control of power system is one of important subjects in view of system operation and control. That is even though the rapid load disturbances were applied to the given power system, the stable and reliable power should be supplied to the users, converging unconditionally and rapidly the frequency deviations and the tie-line power flow one on each area into allowable boundary limits. Nonetheless of such needs, if the internal parameter perturbation and the sudden load variation were given, the unstable phenomenal of power system can be often brought out because of the large frequency deviation and the unsuppressible power line one. Therefore, it is desirable to design the robust neuro-fuzzy controller which can stabilize effectively the given power system as soon as possible. In this paper the robust neuro-fuzzy controller was proposed and applied to control of load frequency over multi-area power system. The architecture and algorithm of a designed NFC(Neuro-Fuzzy Controller) were consist of fuzzy controller and neural network for auto tuning of fuzzy controller. The adaptively learned antecedent and consequent parameters of membership functions in fuzzy controller were acquired from the steepest gradient method for error-back propagation algorithm. The performances of the resultant NFC, that is, the steady-state deviations of frequency and tie-line power flow and the related dynamics, were investigated and analyzed in detail by being applied to the load frequency control of multi-area power system, when the perturbations of predetermined internal parameters. Through the simulation results tried variously in this paper for disturbances of internal parameters and external stepwise load stepwise load changes, the superiorities of the proposed NFC in robustness and adaptive rapidity to the conventional controllers were proved.

• 대한한방내과학회지
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• 제18권1호
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• pp.255-269
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• 1997

This study has been carried out to investigate the cause, pathological mechanism and treatment of CVA in Youmunsachin(儒門事親), written by Changjongjung(張從政) The results were follows : 1. The cause of CVA in Youmunsachin(儒門事親) was quotated from the theory of Naekyung(內經), Guel-eum-pung-mok(厥陰風木) and exogenous wind evil(外感風邪) on weakness of human body. 2. The pathological mechenism of CVA was that flows of Ki(氣) were obstructive, or executive heart(心) suppress lung(肺) and weakened lung(金) did not control liver(肝), executive liver brought to Gan-pung-nae-dong(肝風內動), and he thought that onset of CVA was frequent in 3nd, 4th, 9th. 10th, 12th lunar month. 3. In treatment of CVA, Han-to-ha-bub(汗吐不法, sweating vomiting passing stool method to remove evil) was used. His treatment was divided into ten sweating vomiting passing stool method by medication for internal use, one vomiting method by medication for external use and one sweating method by using acupuncture. 4. In treatment of CVA, when emergency time, vomiting and passing stool method were used, and then, method of Yangheulgeopung(養血祛風), Chungeulgeodam(淸熱去痰), Pyorissanghae(表裏雙解), Whalheultonglak(活血通絡) was used. 5. In the form of prescription, he used the form of Hwan, San(丸, 散), and he used toxic agent frequently.

• International journal of advanced smart convergence
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• 제10권2호
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• pp.175-186
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• 2021

We have studied the speed regulation of the permanent magnet synchronous motor (PMSM) servo system in this paper. To optimize the PMSM servo system's speed-control performance with disturbances, a non-linear speed-control technique using a back-propagation neural network (BP-NN) algorithm forthe controller design of the PMSM speed loop is introduced. To solve the slow convergence speed and easy to fall into the local minimum problem of BP-NN, we develope an improved BP-NN control algorithm by limiting the range of neural network outputs of the proportional coefficient Kp, integral coefficient Ki of the controller, and add adaptive gain factor β, that is the internal gain correction ratio. Compared with the conventional PI control method, our improved BP-NN control algorithm makes the settling time faster without static error, overshoot or oscillation. Simulation comparisons have been made for our improved BP-NN control method and the conventional PI control method to verify the proposed method's effectiveness.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2000년도 추계학술대회 학술발표 논문집
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• pp.195-198
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• 2000

Sliding mode control method is popularly used for robustness to distrurbance and variance of systems internal parameter. However, one of the serious problem of this method is Chattering which occurs in neighborhood of sliding manifold. Another problem is that we cannot expect robustness before system starts sliding mode. A new tuning method of sliding manifold which changes the parameter of sliding manifold dynamically using Wavelet Neural Network is proposed in this paper. We can expect the better performance in sliding mode control by the wavelet neural networks excellent property of approximating arbitrary function for multi-resolution analysis and decrease chattering drastically.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.842-846
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• 1993

Because of complexity, neural network is difficult to learn. So if internal representation[1] can be performed successfully, it is possible to use perceptron learning rule. As a result, learning is easier. Therefore the method of internal representations applied to the "XOR" problem, and the "spirals" problem. And then using the above results, the structure of neural network for computing is embodied.mputing is embodied.

• 소음진동
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• 제8권1호
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• pp.171-179
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• 1998

The present paper deals with the dynamic stability and vibration suppression of a cantilevered flexible pipe having a tip mass under an internal flowing fluid. The equations of motion are derived by energy expressions using extended Hamilton's principle, and some analytical results using Galerkin's method are presented. Finally, the vibration suppression technique by means of an internal fluid flow is demonstrated experimentally.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.77.6-77
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• 2001

R/C helicopter has been used to several fields of military affairs, investigation, searching and toys because it has small size, hovering and vertical take-off characteristics etc. Therefore it needs more realizable control method. The paper introduces simulation and experimental results for control of a helicopter training simulator by self tuning control method. It is assumed that the helicopter is operated at the state of hovering motion and the model is induced. The self tuning control method incorporates the concepts of the well known internal model principle and annihilator polynomial for reference input and disturbance. The controller design is separated into two cases that the plant parameters are known or not. To realize ...

• 대한임상검사과학회지
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• 제36권2호
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• pp.239-244
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• 2004

Recently automatic equipment has been well popularized for the erythrocyte sedimentation rate, a widely used test, but no standard quality control has been established yet. Thus, we are going to report a case that established and applied a quality control method using the TEST 1 automatic analyzer. For internal quality control, we adopted the repeatability test through comparison with daily mean check, with a manual method using patients' specimens and with the results of a test on the previous day. In order to set the tolerance standard for each quality control method, we compared the results of 50 specimens that showed a wide range of ESR results and examined correlation and differences according to result. After setting the tolerance standard, we applied the standard at tertiary university hospitals for 120 days and investigated positive rates and re-examination rates. If the tolerance standard was exceeded, the cause was also identified. We selected a specimen of below 25 mm/hr (T1), one between 26-50 mm/hr (T2) and one of over 51 mm/hr (T3) at random. The correlation between the manual method and the automatic method was quite high (r=0.98), and it is found appropriate to set based on differences in result values below 25 mm/hr, the upper limit of the reference value, and based on differences in the percentage of result values above 25 mm/hr. Accordingly, we set the criteria for rejection above 10 mm/hr and above 20%. When the criteria were applied in the laboratory, 1.7% of specimens in the range of T1, 8.3% of those in the range of T2 and 7.5% of those in the range of T3 were rejected. Because all the rejected ones fell within the tolerance limit in re-examination calibration verification was not carried out. With the wide popularization of erythrocyte sedimentation rate analyzers that can carry out a lot of tests quickly using automatic methods, it is necessary to improve the reliability of test results by establishing internal quality control policies. We expect that an agreed standard quality control method may be established based on the method proposed in this study.

• 한국간호교육학회지
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• 제14권1호
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• pp.117-126
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• 2008

Purpose: The aim of this study was to research caregiver trainees, and to understand the degree of subjective quality of life and internal and external locus control, and to examine the relationships between these variables. Method: The subjects of the research were 348 trainees at a Jeonju city caregiver training center. The subjective quality of life and the characteristics of locus control were used as measuring tools. The collected data was analyzed by the SAS 9.1 program. Result: The degree of subjective quality of life was significantly different according to the general characteristics of age (F=2.83, p=0.02), marital status (F=3.34, p=0.01), and willingness to work (F=3.94, p=0.05). The degree of internal locus control was significantly different according to the general characteristic of marital status (F=3.0 p=0.01). External locus control was significantly different according to the general characteristics of age (F=9.77, p=0.00), occupation (F=2.91, p=0.01), educational level (F=9.65, p=0.00), monthly income (F=3.81, p=0.00), educational institution (F=2.06, p=0.04), educational experience (F=4.15, p=0.00), and subjects willingness to work (t=8.71, p=0.00). A significant correlation was identified between the subjective quality of life and internal locus control (r=0.23, p=0.0001). Conclusion: A significant correlation was shown between subjective quality of life and internal locus control of the caregiver trainees.