• Title/Summary/Keyword: Validity of diagnosis

검색결과 407건 처리시간 0.026초

Low Cost Rotor Fault Detection System for Inverter Driven Induction Motor

  • Kim, Nam-Hun;Choi, Chang-Ho
    • Journal of Electrical Engineering and Technology
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    • 제2권4호
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    • pp.500-504
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    • 2007
  • In this paper, the induction motor rotor fault diagnosis system using current signals, which are measured using axis-transformation method, and speed, which is estimated using current information, are presented. In inverter-fed motor drives unlike line-driven motor drives the stator currents have numerous harmonics components and therefore fault diagnosis using stator currents is very difficult. The current and speed signal for rotor fault diagnosis needs to be precise. Also, high resolution information, which means the diagnosis system, demands additional hardware such as low pass filter, high resolution ADC, encoder and etc. Therefore, the proposed axis-transformation and speed estimation method are expected to contribute to low cost fault diagnosis systems in inverter-fed motor drives without the need for an encoder and any additional hardware. In order to confirm validity of the developed algorithms, various experiments for rotor faults are tested and the line current spectrum of each faulty situation using Park transformation and speed estimation method are compared with the results obtained from fast Fourier transforms.

Rotor Fault Detection System for Inverter Driven Induction Motors using Currents Signals and an Encoder

  • Kim, Nam-Hun
    • Journal of Power Electronics
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    • 제7권4호
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    • pp.271-277
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    • 2007
  • In this paper, an induction motor rotor fault diagnosis system using current signals, which are measured using the axis-transformation method is presented. Inverter-fed motor drives, unlike line-driven motor drives, have stator currents which are rich in harmonics and 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, an encoder and additional hardware. Therefore, the proposed axis-transformation method 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 the Park transformation, is compared with the results obtained from the FFT(Fast Fourier Transform).

한국판 아스퍼거 증후군 진단척도의 타당화 및 진단 분할점 산출 (A Study of the Validity of and Cut-Off Scores for the Korean Version of Asperger Syndrome Diagnostic Scale)

  • 김하나;신민섭
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제22권2호
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    • pp.81-88
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    • 2011
  • Objectives : This study examined the reliability and validity of the Korean version of Asperger Syndrome Diagnostic Scale (K-ASDS), to calculate the cut-off score in the diagnosis of Asperger syndrome. Further, we examined classification error rate when applying cut-off scores. Methods : One hundred sixty-seven children participated in this study, including 46 with Asperger syndrome, 26 with PDD or PDD NOS, 43 with ADHD, and 52 normal children. Results : An ANCOVA demonstrated no significant differences in the K-ASDS total score between the Asperger and the PDD & PDD NOS groups. However, these groups did show significantly higher scores than the ADHD and normal groups. Among the five subscales on the K-ASDS, the Asperger group obtained significantly higher scores on the language and cognition subscales than the PDD & PDD NOS groups. Two scales were found to be useful in distinguishing the Asperger group from the PDD & PDD NOS group through a discriminant analysis. According to an analysis of ROC curve, the cut-off score on the K-ASDS for the diagnosis of PDD including Asperger syndrome was 121. Conclusion : We discussed that K-ASDS has pretty limit.

한국 표준 간호행위 분류 (The Classification of Standard Nursing Activities in Korea)

  • 박정호;성영희;송미숙;조정숙;심원희
    • 대한간호학회지
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    • 제30권6호
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    • pp.1411-1426
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    • 2000
  • A nursing activity classification for hospitalized patients was performed based on an article review regarding nursing definition and nursing activity classification system. The study was conducted as follows: 1) Taxonomy was developed by the research team through the Delphi process and review article. The taxonomy consists of four nursing processes, (assessment, diagnosis, intervention and evaluation) and twelve nursing activity domains space (resperation, nutrition, elimination, exercise/alignment maintenance, comfort, hygiene, safety, spiritual support, counseling/ education, medication, communication, patient and information management). 2) First, nursing activities of the intervention process were listed and then classified by the nursing process of assessment, diagnosis, intervention and evaluation. The list consists of twelve nursing activity domains and 136 nursing activities. 3) A pilot study was conducted in two hospitals to verify validity and appropriateness of nursing activities. 4) The content validity index, which was calculated by 6 clinical practice experts, was 0.95. Also, a nursing activity classification system should also be developed in the department of community nursing and home health care nursing.

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생체 간이식 공여자에서 비알코올성 지방간 질환의 진단에 있어서 초음파검사의 타당도 연구 (Validity of Ultrasonography in the Diagnosis of Non-alcoholic Fatty Liver Disease in Living Liver Donors)

  • 김연민;한동균
    • 한국콘텐츠학회논문지
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    • 제11권10호
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    • pp.342-348
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    • 2011
  • 생체 간이식 공여자를 대상으로 시행되는 간생검 조직소견의 지방변성 정도와 복부초음파검사 결과를 분석하여, 지방간 질환의 진단에 있어서 초음파검사의 타당성을 알아보고자 하였다. 총 지방 함유량 10% 기준으로 범주화 하여 10% 이하를 음성, 10% 이상을 양성으로 하였을 때 초음파검사의 민감도는 64.6%이었고, 특이도는 68% 이었으며, 양성 예측도와 음성 예측도는 각각 76.8%, 54% 이었다. 초음파검사 결과 정상과 경증을 음성으로, 중등도를 양성으로 조작하였을 때 초음파검사의 민감도는 26.8% 이었고, 특이도는 100% 이었으며, 양성 예측도와 음성 예측도는 각각 100%, 45.5% 이었다. 총 지방 함유량 10% 이상을 상태변수(State variable)로 ROC curve 분석을 시행 하였을 때. 간/신장 명도비의 곡선하면적(Area under curve, AUC)은 0.859로 지방간을 예측하는데 좋은 지표로 나타났으며, 95% 신뢰구간(CI: 0.795~0.922)이 통계적으로 유의한 값을 보였다(p<0.001). 지방간진단에 있어서 복부초음파검사는 간생검 병리학적 결과를 예측하는데 높은 타당도를 보였다.

전문가용 사상체질진단지의 신뢰도와 타당도 검사 (The Reliability and Validity Test of Sasangin Diagnostic Questionnaire for Specialist(SDQ_S))

  • 박윤성;김제신;박병주;유정희;이준희;고병희;이의주
    • 사상체질의학회지
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    • 제28권2호
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    • pp.110-122
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    • 2016
  • Objectives The purpose of this study was to develop the Sasangin Diagnostic Questionnaire for Specialist(SDQ_S) and to evaluate the reliability and validity of SDQ_S for standardization of sasang constitutional diagnosis by korean medicine Specialist in clinical practice.Methods SDQ_S was developed through discussions of three sasang constitutional medical specialist. We recruited 210 subjects aged from 20 to 70, and conducted the evaluation of SDQ_S and sasang constitutional diagnosis. For the reliability test, internal consistency was examined by calculating the cronbach's α coefficient on 88 items excepted measurements of trunk, and independence and agreement was examined by chi-square test and McNemar test for 84 subjects which retested SDQ_S. For the validity test, discriminant functions was derived from the sample group(105 subjects), and they were applied to the test group(105 subjects). We identified the hit-ratio of SDQ_S in the test group.Results and Conclusions In the reliability test, the cronbach's α coefficient was 0.664 and 87 items(98.9%) have dependent relationships between 1st test and 2nd test. And 39 items(44.3%) have high agreements(0.8≤McNemar), 26 items(29.5%) have common agreements(0.4≤McNemar<0.8). In the validity test, four discriminant variables(Soeum Index, Taeeum Index, Torso Ratio I, Taeyang Index) were selected, and two discriminant functions were derived. Total hit-ratio was 74.2%, and hit-ratio of Taeeumin(76.7%) was higher than that of Soeumin(75.9%) and Soyangin(69.7%). SDQ_S has good reliability and validity for sasang constitutional diagnosis.

악관절장애 환자의 임상 및 측사위경두개 촬영에 의한 진단과 자기공명영상에 의한 진단의 비교연구 (VALIDITY OF CLINICAL, TRANSCRANIAL RADIOGRAPHIC AND MAGNETIC RESONANCE IMAGING METHOD IN THE DIAGNOSIS OF INTERNAL DERANGEMENT OF TEMPOROMANDIBULAR JOINT)

  • 최정희;정현대
    • 치과방사선
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    • 제21권2호
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    • pp.327-336
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    • 1991
  • The purpose of this study was to evaluate the validity among the clinical, transcraial radiographic and MRI diagnosis in internal derangement of the temporomandibular joint. Fourty two temporomandibular joints were assessed in twenty one patients who visited the dental department of Chonnam National University Hospital with the complaint of temporomandibular disorder from Oct. 1990 to Oct. 1991. The results were as follows: 1. In the clinically symptomatic 29 TMJs, 26 (89.7%) joints reveal disc displacement and 3 (10.3%) joints reveal normal disc position on MRI. The sensitivity of clinical diagnosis was 0.77, and the specificity was 0.63. 2. In the normal 22 TMJs on the trans cranial radiographic finding, 16 (72.7%) joints reveal disc displacement, and 6 (27.3%) joints reveal normal disc position on MRI. In the abnormal 20 TMJs on the transcranial radiographic finding, 18 (90%) joints reveal disc displacement, and 2 (10%) joints reveal normal disc position on MRI. The sensitivity of trans cranial radio- graph was 0.53, and the specificity was 0.75.

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A Validation Study of the CARS-2 Compared With the ADOS-2 in the Diagnosis of Autism Spectrum Disorder: A Suggestion for Cutoff Scores

  • Seong-In Ji;Hyungseo Park;Sun Ah Yoon;Soon-Beom Hong
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제34권1호
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    • pp.40-50
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    • 2023
  • Objectives: This study examined the validity of the Childhood Autism Rating Scale, Second Edition (CARS-2) compared with the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) in identifying autism spectrum disorder (ASD). Methods: A total of 237 children were tested using both the CARS-2 and ADOS-2. We examined the correlation using Pearson's correlation analysis. In addition, we used a receiver operating characteristic graph to determine the optimal standard version of the CARS-2 (CARS2-ST) cutoff score for ASD diagnosis using the ADOS-2. Results: The concurrent validity of the CARS2-ST was demonstrated by a significant correlation with the ADOS-2 (r=0.864, p<0.001). The optimal CARS2-ST cutoff scores were 30 and 28.5 for identifying autism and autism spectrum, respectively, based on the ADOS-2. Conclusion: We suggest a newly derived CARS2-ST cutoff score of 28.5 for screening ASD and providing early intervention.

가족체계 진단 척도 개발 및 타당화 연구 - Minuchin의 구조적 가족치료 이론에 기초하여 - (The Development of the Family System Diagnosis Scale and Its Validity - On the Basis of Minuchin′s Structural Family Therapy Theory-)

  • 이미옥
    • 대한가정학회지
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    • 제42권3호
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    • pp.179-193
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    • 2004
  • The purpose of this study was to develop the Family System Diagnosis Scale and to examine its reliability and validity. The subscales of the questionnaire included scores on seven constructs. In order to define constructs accurately, a careful review of Minuchin's writings, the writings of other family therapists, and relevant articles on family interaction was undertaken. A pool of 150 items was given to eight family counselors along with a description of Minuchin' s concepts. The counselors were asked to choose the category each statement fit and to rate the degree of fit using the 3-point scale. Using exploratory factor analysis, confirmatory factor analysis and Linear Structural Relationship(LISREL), six subdimensions of individuation and 55 items of FSDS were identified; enmeshmen disengagement(16 items), parent coalition generational coalition(6 items), flexibility rigidity(5 items), spouse conflict resolved unresolved(8 items), mother-child cohesion estrangement(10 items), father-child cohesion estrangement(10 items). 356 adolescents(ages 13∼18), 356 fathers, 356 mothers in Seoul, Busan, Dague, Incheun, Dajeun, Ulsan, and Kwangju were completed the Family System Diagnosis Scale(FSDS). The reliability of the scale was calculated by Cronbach's a Coefficient and the total a = .94 and the calculation for each factor was .87, .60, .77, .80 and .79 respectively.

유중가스 분석법과 지능형 확률모델을 이용한 유입변압기 고장진단 (Fault Diagnosis of Oil-filled Power Transformer using DGA and Intelligent Probability Model)

  • 임재윤;이대종;지평식
    • 전기학회논문지P
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    • 제65권3호
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    • pp.188-193
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    • 2016
  • It has been proven that the dissolved gas analysis (DGA) is the most effective and convenient method to diagnose the transformers. The DGA is a simple, inexpensive, and non intrusive technique. Among the various diagnosis methods, IEC 60599 has been widely used in transformer in service. But this method cannot offer accurate diagnosis for all the faults. This paper proposes a fault diagnosis method of oil-filled power transformers using DGA and Intelligent Probability Model. To demonstrate the validity of the proposed method, experiment is performed and its results are illustrated.