• 사상체질의학회지
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• 제26권3호
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• pp.295-303
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• 2014

Objectives It is very important to diagnose Sasang Constitution (SC) correctly. The aim of this study was to reveal the concordance and validity of the specialists in Sasang Constitutional Medicine (SCM). Methods Three experts who had more than 5 years of experience and used more than 90% of Sasang Constitutional prescription in clinical practice of SCM participated in this study. The data composed of body shape, face, voice, temperament and physio-pathological symptoms were collected in the Korea Constitutional Multicenter Bank and 81 subjects' data were extracted randomly. The experts reviewed all 81 subjects data independently. Kappa analysis was conducted. Results 1) The concordance is from 52.5% to 68.4% among three experts. 2) The validity between individual expert and gold standard is from 54.3% to 63% and Kappa's coefficients are from 0.283 to 0.421. 3) The validity is from 68.5% to 70.7% when two or three experts agree the Sasang constitution independently and 75.7% when all of experts agree it. Conclusions The concordance and validity of experts in SCM seems to be moderate. We think further study is needed.

• Clinical and Experimental Pediatrics
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• 제55권3호
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• pp.83-87
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• 2012

Several authors suggested that the clinical characteristics of incomplete presentation of Kawasaki disease are similar to those of complete presentation and that the 2 forms of presentation are not separate entities. Based on this suggestion, a diagnosis of incomplete Kawasaki disease in analogy to the findings of complete presentation is reasonable. Currently, the diagnosis of incomplete Kawasaki disease might be made in cases with fewer classical diagnostic criteria and with several compatible clinical, laboratory or echocardiographic findings on the exclusion of other febrile illness. Definition of incomplete presentation in which coronary artery abnormalities are included as a necessary condition, is restrictive and specific. The validity of the diagnostic criteria of incomplete presentation by the American Heart Association should be thoroughly tested in the immediate future.

• International Journal of Air-Conditioning and Refrigeration
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• 제16권4호
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• pp.137-144
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• 2008

This study deals with on-line fault detection and diagnosis(FDD) for heat exchangers of a variable speed refrigeration system(VSRS) based on current information. The current residual which is the difference between real detected current from current sensors and estimated current from no fault model was utilized to diagnose faults of the heat exchangers. Comparing to the conventional FDD of constant refrigeration system based on temperature and pressure information, the suggested FDD method shows better robustness to the VSRS which has a feedback control loop. Moreover the suggested method can be expected more precise and faster diagnosis of faults about heat exchangers. Throughout some experiments, the validity of the method was verified.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제2권1호
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• pp.33-37
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• 2002

Insulation aging diagnosis system provides early warning regarding electrical equipment defects. Early warning is very important in that it can avoid great losses resulting from unexpected shutdown of the production line. Since relations of insulation aging and partial discharge dynamics are non-linear. it is very difficult to provide early warning in an electrical equipment. In this paper, we propose the design method of insulation aging diagnosis system that use a electromagnetic wave and acoustic signal to diagnose an electrical equipment. Proposed system measures the partial discharge on-line from DAS(Data Acquisition System and acquires 2D patterns from analyzing it. For filtering the noise contained in sensor signals we used ICA algorithms. Using this data, we design of the neuro-fuzzy model that diagnoses an electrical equipment and is investigated in this paper. Validity of the new method is asserted by numerical simulation.

• Journal of Power Electronics
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• 제16권2호
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• pp.695-703
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• 2016

A fuel cell power conditioning system for online diagnosis and load leveling under the condition of varying load is developed in this study. The proposed system comprises a unidirectional boost converter and a bidirectional buck-boost converter with a battery. The system operates in two different modes. In normal mode, the bidirectional converter is utilized for load leveling; in diagnostic mode, it is utilized to control load voltage while the boost converter generates perturbation current to implement the online diagnosis function through in-situ electrochemical impedance spectroscopy (EIS). The proposed method can perform EIS for a fuel cell under varying-load conditions with no influence on the load. The validity and feasibility of the proposed system are verified by experiments, and the design procedure of the proposed system is detailed.

• 조명전기설비학회논문지
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• 제26권3호
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• pp.61-68
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• 2012

This paper deals with a fault diagnosis algorithm for open faults in the switching devices of PWM inverter-fed IPMSM (Interior Permanent Magnet Synchronous Motor) drive. The proposed diagnostic algorithm is realized in the controller using the informations of three-phase currents or reference line-to-line voltages, without requiring additional equipments for fault detection. Under switch open fault conditions, the conventional dq model used to control an AC motor cannot directly be applied for the analysis of drive system, since three-phase balanced condition does not hold. To overcome this limitation, a fault model based on the line-to-line voltages is employed for the simulation studies. For comparative performance evaluation through the experiments, the entire control system is implemented using digital signal processor (DSP) TMS320F28335. Simulations and experimental results are presented to verify the validity of the proposed diagnosis algorithm.

• 전기학회논문지P
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• 제56권4호
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• pp.168-172
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• 2007

The global environment deteriorating which originated from using of fossil fuel is an serious problem for human being to solve. The photovoltaic energy has been considered as a solution. In advanced countries, research and development for photovoltaic(PV) energy system is carrying on. Once installed, a PV array requires maintenance and fault diagnosis other than an occasional cleaning. In this research, the proposed system monitor and diagnosis the output of PV array by on-line for maintenance of PV power plant. The validity of proposed system is verified using sample system.

• Journal of Power Electronics
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• 제9권3호
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• pp.377-385
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• 2009

In this paper, a diagnosis method for switch open-circuit faults in three-phase PWM inverters is proposed, which employs support vector machine (SVM) as classifying method. At first, a discrete wavelet transform (DWT) is used to detect a discontinuity of currents due to the fault, and then the features for fault diagnosis are extracted. Next, these features are employed as inputs for the SVM training. After training, the SVM produces an optimized boundary which is used identifying the fault. Finally, the fault classification is performed online with instantaneous features. The experimental results have verified the validity of the proposed estimation algorithm.

• 동력기계공학회지
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• 제9권4호
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• pp.187-193
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• 2005

In this paper, we proposes a man-machine interface design for fault diagnosis system with inter-node search method in a Petri net model. First, complicated fault cases are modeled as the Petri net graph expressions. Next, to find out causes of the faults on which we focus, a Petri net model is analyzed using the backward reasoning of transition-invariance in the Petri net. In this step, the inter-node search method algorithm is applied to the Petri net model for reducing the range of sources in faults. Finally, the proposed method is applied to a fault diagnosis of a refrigeration system to confirm the validity of the proposed method.

• Tuberculosis and Respiratory Diseases
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• 제47권3호
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• pp.311-320
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• 1999

연구 배경 : 최근 전세계적으로 결핵이 증가하며 새로운 문제로 대두되고 있으며, 특히 결핵의 유병률이 높은 우리나라의 경우에는 민감도가 높으며 간편한 검사방법 이 필요하다. M. tuberculosis 항원을 사용한 rapid membrane based assay 검사 방법으로 최근에 폐결핵 환자의 결핵항원 특이 항체를 검출한다고 알려진 상용화된 2 가지 kit를 이용하여 폐결핵의 혈청학적 진단 가능성을 알아보고자 하였다. 방법 : 1998년 3월부터 9월까지 충남대학교 병원에서 입원 치료를 받은 호흡기 환자 총 45예를 대상으로 하였다. 객담 도말 양성의 활동성 폐결핵 22예와 비활동성 폐결핵 14예 그리고 대조군으로 비결핵성 호흡기 질환 9예를 대상으로 하여 STAT-PAK ULTRA FAST$^{(R)}$ 및 ICT tuberculosis$^{(R)}$ 검사를 실시하여 결핵 혈청 검사의 유용성을 알아보고 자하였다. 결과: STAT-PAK ULTRA FAST$^{(R)}$의 경우에는 폐결핵과 비활동성 폐결핵의 비교에서 민감도는 77.3%, 28.6%, 양성 63.0%, 음성 예측도는 44.4%, 위양성률은 71.4%, 위음성률은 22.7% 이었고, 활동성 폐결핵과 비결핵성 호흡기 질환의 비교에서는 민감도는 77.3%, 특이도는 33.3%, 양성 예측도는 73.9%, 음성 에측도는 37.5%, 위양성률은 66.7%, 위음성률은 22.7% 이었다. ICT tuberculosis$^{(R)}$의 경우에는 활동성 폐결핵과 비활동성 폐결핵의 비교에서는 민감도는 54.5%. 특이도는 57%, 양성 예측도는 66.7%, 음성 예측도는 44.4%, 위양성률은 42.9%, 위음성률은 45.4 %이었고, 활동성 폐결핵과 비결핵성 호흡기 질환에서는 민감도는 54.5%, 특이도는 100%, 양성 예측도는 100%, 음성 예측도는 47.4%. 위양성률은 0%, 위음성률은 45.4%이었다. 폐결핵의 중증정도(extent) 와 양성율은 상기 2가지 kit에서 큰 차이가 없었다. 결론: 따라서 상기 2가지의 kit는 항체 반응이 다양하여 임상적으로 폐결핵의 진단에 이용하는 것에는 문제가 있다고 생각되며, 일단 양성반응을 보인 환자의 경우, 항결핵제 투여에 따른 추적 검사에서 항체가의 변화가 있는지에 대한 연구가 필요하리라 생각된다.