• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.185-193
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• 2011

There is no exact standard of detecting pulmonary tuberculosis(TB) in digital image of simple chest radiography. In this study, I experimented on the principal components analysis(PCA) algorithm in the past and suggested six other parameters as identification of TB lesions. The purpose of this study was to develop and test computer aided diagnosis(detection) method for the detection and measurement of pulmonary abnormalities on digital chest radiography. It showed comparatively low recognition diagnosis rate using PCA method, however, six kinds of texture features parameters algorithm showed similar or higher diagnosis rates of pulmonary disease than that of the clinical radiologists. Proposed algorithms using computer-aided of texture analysis can distinguish between areas of abnormality in the chest digital images, differentiate lesions having pulmonary disease. The method could be useful tool for classifying and measuring chest lesions, it would play a major role in radiologist's diagnosis of disease so as to help in pre-reading diagnosis and prevention of pulmonary tuberculosis.

• Korean Journal of Acupuncture
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• v.28 no.1
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• pp.23-37
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• 2011

Objectives : The pulse diagnosis is an important method in Oriental Medicine. The aim of this study is to measure the similarity of the diagnosis by a traditional method using doctor's hand for feeling of pulse and by pulse diagnosis apparatus using Hwang-Je (HJ) pulse analyser, Hui-Su (HS) pulse analyser on Chon, Kwan and Chuk. Methods : Four korean medical doctors and HJ pulse analyser, HS pulse analyser have measured the speed (遲數), the size (微細弱緩大), and the depth (浮沈) of pulse waves of 23 volunteers. First, four korean medical doctors measured pulse waves of volunteers. And then, the pulse waves of volunteers were measured by HJ pulse analyser, HS pulse analyser. This was performed on the right Chon, Kwan and Chuk. Results : The traditional method and the HJ pulse analyser method had the 60.9% matches on the values of the pulse speed condition, the HS pulse analyser method had the 78.3% matches on the values of the pulse speed condition. The traditional method and the HJ pulse analyser method had the 56.5% (Chon), 65.2% (Kwan), 78.3% (Chuk) matches on the values of the pulse size condition, the HS pulse analyser method had the 65.2% (Chon), 13.0% (Kwan), 39.1% (Chuk) matches on the values of the pulse size condition. The traditional method and the HJ pulse analyser method had the 43.5% (Chon), 26.1% (Kwan), 47.8% (Chuk) matches on the values of the pulse depth condition, the HS pulse analyser method had the 45.5% (Chon), 30.4% (Kwan), 36.8% (Chuk) matches on the values of the pulse depth condition. Conclusions : According to these results, we suggest that the pulse analyser is necessary to develope for its high similarities with the traditional pulse diagnosis.

• Journal of Power Electronics
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• v.12 no.1
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• pp.120-127
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• 2012

Fault diagnosis technique of electrical drives is becoming more and more important, since voltage fed converter system has become industrial standard in many applications. Many studies have been conducted an inverter fault diagnosis for induction motors. However, there are few researches about fault diagnosis of 3-phase ac/dc PWM (Pulse Width Modulation) converter compared to the dc/ ac inverter. The ac/dc converter is the opposite of dc/ac inverter at current flow. Also, inverter and converter have different current patterns under the same condition of IGBT (Insulated gate bipolar transistor) open switch fault. Therefore, it is difficult to apply intact diagnosis methods of inverter to the converter. This paper proposes modified fault detection methods for IGBT open switch fault in 3-phase ac/dc PWM converter by modifying established fault diagnostic methods for dc/ac inverters.

• Journal of Oriental Neuropsychiatry
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• v.24 no.spc1
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• pp.23-36
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• 2013

Objectives : The purpose of this guideline is to show the evidence-based guidelines of diagnosis and evaluation of Hwabyung by the synthesis and organization of existing research contents. Methods : We investigated the existing research on the concept of Hwabyung. Further, we investigated the diagnostic tools, self-diagnostic method, symptoms assessment tools, oriental medical diagnostic methods, treatment evaluation tools and other testing methods of Hwabyung. Results : There was a Hwabyung diagnostic interview schedule (HIBDS) in the standardized measure for the diagnosis of Hwabyung. In the symptoms assessment tools of Hwabyung, there was a self-report measurement tool of Hwabyung and measurement tool of Hwabyung to be evaluated by the interviewer. In the oriental medical diagnostic method, there was an instrument of pattern identification for Hwabyung. In the treatment assessment tool, there was an instrument of oriental medical evaluation for Hwabyung. In addition, MMPI, SCL-90R, Zung's self-rating anxiety scale (SAS), Zung's self-rating depression scale (SDS), State-Trait Anger Expression Inventory (STAXI) and etc. can be used for the diagnosis and assessment of Hwabyung. Conclusions : We expect 'Clinical Guidelines for the Treatment of Hwabyung' to be useful for the diagnosis and assessment of Hwabyung.

• Journal of Power Electronics
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• v.9 no.2
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• pp.224-231
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• 2009

The induction motor rotor fault diagnosis system using current signals, which are measured using an axis-transformation method, is presented in this paper. In inverter-fed motor drives, unlike line-driven motor drives, the stator currents are rich in harmonics; therefore fault diagnosis using stator current is not trivial. The current signals for rotor fault diagnosis need precise and high resolution information, which means the diagnosis system demands additional hardware such as a low pass filter, high resolution ADC, and encoder, etc. The proposed axis-transformation method with encoder and without encoder is expected to contribute to a low cost fault diagnosis system in inverter-fed motor drives without the need for any additional hardware. In order to confirm the validity of the developed algorithms, various experiments for rotor faults are tested and the line current spectrum of each faulty situation using Park transformation is compared with the results obtained from fast Fourier transforms.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.90.1-90.1
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• 2011

This technology is applicable to Electrical vehicle that using Energy from Hydrogen Fueled Cell. Electricity & water is got from chemical reaction between H2 & O2 in stack. This technology is used when fault diagnosis of Fuel cell is needed. It is General method that measure each cell's voltage of stack for fault diagnosis. but, this technology is method of measuring entire voltage of stack. For this reason, fault diagnosis system is simplified and cost of system is lower than previous one. In normal stack condition, characteristic graph of voltage-current has linearity. In fault stack condition, it has non-linearity. we use this characteristic to diagnosis of stack fault. In this technology, Specific frequency current is injected into stack & Stack voltage is measured in response. After that, stack voltage difference is analyzed to diagnosis of stack fault. Presently, Development of current injection module & basic program of THDA is finished. in future we will develop the technology of precise measurement technology about entire stack voltage.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.32 no.2
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• pp.56-63
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• 2021

Laryngopharyngeal reflux disease (LPRD) is an inflammatory condition of the upper aerodigestive tract mucosa induced by reflux content from stomach. Some of vocal cord diseases are associated with laryngopharyngeal reflux. Because of the pathophysiological features, proton pump inhibitor shows therapeutic effect on some vocal cord diseases. As like that, the gastric reflux contents can make macroscopic or microscopic morphological changes in the upper aerodigestive tract mucosa. Although the pathophysiology of LPRD is relatively clear, clinical diagnosis is still difficult. The diagnosis of LPRD includes objective tests such as 24-hours multichannel intraluminal impedance-pH metry and subjective tests such as questionnaire method. However, the objective verification of reflux is difficult due to invasiveness of the method, and the questionnaire methods have limitations because many symptoms are not specific for LPRD. Moreover, most methods are not fully standardized until now. Despite these limitations, many researchers are struggling to standardize diagnosis and treatment of LPRD, and there are several new achievements recently. Therefore, the purpose of this article is to review the recent literature on the clinical presentation, diagnosis, and treatment of LPRD, and to systematize our knowledge.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.5
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• pp.450-457
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• 2004

In this research, the automatic synthesis of knowledge models is proposed. which are the basis of the methods using qualitative models adapted widely in fault diagnosis and hazard evaluation of chemical processes. To provide an easy and fast way to construct accurate causal model of the target process, the Role-Behavior modeling method is developed to represent the knowledge of modularized process units. In this modeling method, Fault-Behavior model and Structure-Role model present the relationship of the internal behaviors and faults in the process units and the relationship between process units respectively. Through the multiple modeling techniques, the knowledge is separated into what is independent of process and dependent on process to provide the extensibility and portability in model building, and possibility in the automatic synthesis. By taking advantage of the Role-Behavior Model, an algorithm is proposed to synthesize the plant-wide causal model, Fault-Causality Graph (FCG) from specific Fault-Behavior models of the each unit process, which are derived from generic Fault-Behavior models and Structure-Role model. To validate the proposed modeling method and algorithm, a system for building FCG model is developed on G2, an expert system development tool. Case study such as CSTR with recycle using the developed system showed that the proposed method and algorithm were remarkably effective in synthesizing the causal knowledge models for diagnosis of chemical processes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.75-78
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• 2001

Recently, the HFPD measurement testing is widely used in partial discharge measurement of HV machines because HFPD measurement testing receives less influence of external noise and has a merit of good sensitivity. Also HFPD testing is able to offer the judgement standard of degradation level of HV machine and can detect discharge signals in live-line. Therefore it is very useful method compare to previous conventional PD testing method and effective diagnosis method in power transformer that requires live-line diagnosis. But partial discharges have very complex characteristics of discharge pattern so it is required continuous research to development of precise analysis method. In recent, the study of partial discharge is carrying out discover of initial defect of power equipment through condition diagnosis and system development of degradation diagnosis using HFPD(High Frequency Partial Discharge) detection. In this study, simulated transformer is manufactured and HFPD occurred from transformer is measured with broad band antenna in real time, the degradation grade of transformer is analyzed through produced patterns in simulated transformer according to applied voltages.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.3
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• pp.243-251
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• 2016

Autonomous Underwater Vehicles (AUVs) generally work in complex marine environments. Any fault in AUVs may cause significant losses. Thus, system reliability and automatic fault diagnosis are important. To address the actuator failure of AUVs, a fault diagnosis method based on the Gaussian particle filter is proposed in this study. Six free-space motion equation mathematical models are established in accordance with the actuator configuration of AUVs. The value of the control (moment) loss parameter is adopted on the basis of these models to represent underwater vehicle malfunction, and an actuator failure model is established. An improved Gaussian particle filtering algorithm is proposed and is used to estimate the AUV failure model and motion state. Bayes algorithm is employed to perform robot fault detection. The sliding window method is adopted for fault magnitude estimation. The feasibility and validity of the proposed method are verified through simulation experiments and experimental data.