• Title/Summary/Keyword: Systematic diagnosis

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A study in fault detection and diagnosis of induction motor by clustering and fuzzy fault tree (클러스터링과 fuzzy fault tree를 이용한 유도전동기 고장 검출과 진단에 관한 연구)

  • Lee, Seong-Hwan;Shin, Hyeon-Ik;Kang, Sin-Jun;Woo, Cheon-Hui;Woo, Gwang-Bang
    • Journal of Institute of Control, Robotics and Systems
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    • v.4 no.1
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    • pp.123-133
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    • 1998
  • In this paper, an algorithm of fault detection and diagnosis during operation of induction motors under the condition of various loads and rates is investigated. For this purpose, the spectrum pattern of input currents is used in monitoring the state of induction motors, and by clustering the spectrum pattern of input currents, the newly occurrence of spectrum patterns caused by faults are detected. For the diagnosis of the fault detected, a fuzzy fault tree is designed, and the fuzzy relation equation representing the relation between an induction motor fault and each fault type, is solved. The solution of the fuzzy relation equation shows the possibility of occurence of each fault. The results obtained are summarized as follows : (1) Using clustering algorithm by unsupervised learning, an on-line fault detection method unaffected by the characteristics of loads and rates is implemented, and the degree of dependency for experts during fault detection is reduced. (2) With the fuzzy fault tree, the fault diagnosis process become systematic and expandable to the whole system, and the diagnosis for sub-systems can be made as an object-oriented module.

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Laboratory Diagnosis for Sarcocystis Asexual Stages in Cattle (소에 감염(感染)된 주육포자충(住肉胞子蟲) 무성생식(無性生殖) 증식형(增殖型)에 대(對)한 실험실적(實驗室的) 진단(診斷))

  • Kang, Yung-bae;Jang, Hwan
    • Korean Journal of Veterinary Research
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    • v.28 no.1
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    • pp.155-163
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    • 1988
  • For the laboratory diagnosis of Sarcocystis infections especially in domesticated food animals, several antificial digestion techniques were applied for the musculature specimens and several staining techniques was applied for the bradyzoites of Sarcocystis species isolated. The digestion technique using trypsin(0.5%) and sodium chloride(0.85%) mixed solution was regarded as the most valuable for the detection of asexual stages of Sarcocystis in bovine musculature specimens. Optimal time for digestion was approximately one to four hours. The trypsion digestion technique with Giemsa's stain could be helpful for the detection of Sarcocystis prolferative forms and for the observation of the nucleus of the parasite. A systematic detection was also performed in an autopsy for a bovine carcass naturally infected with Sarcocystis species, and the asexual stages such as metrocytes and bradyzoites were observed in the specific organs, respectively.

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Diagnosis and treatment of positional plagiocephaly

  • Jung, Bok Ki;Yun, In Sik
    • Archives of Craniofacial Surgery
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    • v.21 no.2
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    • pp.80-86
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    • 2020
  • Positional plagiocephaly is increasing in infants. Positional plagiocephaly is an asymmetric deformation of skull due to various reasons; first birth, assisted labor, multiple pregnancy, prematurity, congenital muscular torticollis and position of head. Positional plagiocephaly can mostly be diagnosed clinically and by physical examinations. The simplest way to assess the severity of plagiocephaly is to use a diagonal caliper during physical examination, which measures the difference between the diagonal lengths on each side of the head. Plagiocephaly can be treated surgically or conservatively. Positional plagiocephaly, which is not accompanied by craniosynostosis, is treated conservatively. Conservative treatments involve a variety of treatments, such as change of positions, physiotherapy, massage therapy, and helmet therapy. Systematic approaches to clinical examination, diagnosis and treatment of positional plagiocephaly can be necessary and the age-appropriate treatment is recommended for patients with positional plagiocephaly.

Fault Tolerant Controller Design for Linear Stochastic Systems with Uncertainties (불확실성을 갖는 선형 확률적 시스템에 대한 고장허용제어기 설계)

  • Lee, Jong-Hyo;Yoo, Jun
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.2
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    • pp.107-116
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    • 2003
  • This paper presents a systematic design methodology for fault tolerant controller against a fault in actuators and sensors of linear stochastic systems with uncertainties. The scheme is based on fault detection and diagnosis(isolation and estimation) using a bank of robust two-stage Kalman filters, and accommodation of the actuator fault by eigenstructure assignment and immediate compensation of the sensor's faulty measurement. In order to clarify the fault feature in test statistics of residual, noise reduction method is given by multi-scale discrete wavelet transform. The effectiveness of our approach Is shown via simulations for a VTOL(vertical take-off and landing) aircraft subjected to parameter variations, external disturbances, process and sensor noises.

A Study for FMEA and Optimization of Failure Diagnosis Sequence Using Probability of Failure Cause (고장원인 확률을 이용한 FMEA와 고장진단 순서의 최적화)

  • Song, Kee-Tae;Kim, Min-Ho;Baek, Young-Gu;Lee, Key-Seo;Kim, Soo-Myong
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.749-757
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    • 2007
  • Recently, with increasing interested in improvement of operational reliability and the systematic maintenance activities, the RCM analysis has been applied and tried to lots of applicable industries. This study covers applying the probability of failure cause to FMEA, and proposes an analytical method for this. Also, the measures of quantitative classification for the result of failure cause probability are addressed. Based on the field data, this thesis presents an identification for causes and characteristics of failure, and reviews them periodically from the above methodologies. As using FMEA applied the probability of failure cause, we in the future can look forward to improvement of efficiency for failure diagnosis & inspection, and reliability.

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Differential Diagnosis of Chronic Coughing (만성 기침의 감별진단)

  • Do, Nam Yong;Park, Jun-Hee
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.27 no.2
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    • pp.87-90
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    • 2016
  • Cough, the most common symptom, encountered in the outpatient clinic can be caused by various underlying diseases. It defines as chronic cough that the duration of cough is more than 8 weeks with a normal chest X-ray findings. The cause of cough can be found out for more than 90% through the appropriate diagnostic approach and Upper airway cough syndrome, Asthma and Gastroesophageal reflex disease are the most common causes of disease to non-smokers. Chronic cough can be due to not one reason but various reasons and achieve good results by a systematic approach to diagnosis and a concrete treatment on the basis of the sufficient understanding of the underlying disease.

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Assessment Framework for Diagnosis of Administration Innovation in Korean Local Government: Case Study of Y-County (지방자치단체 행정혁신 진단 평가프레임웍: Y군청 탐색적 사례연구)

  • Park, Ki-Ho
    • Journal of Digital Convergence
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    • v.5 no.2
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    • pp.37-45
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    • 2007
  • A lot of organizations have been recognized innovative activities as the required process for organizational effectiveness and efficiency in those. Especially, the perceptual scope of innovation indisputability has been extended to the central and local government, and the public organization, which ultimately have the goal of public benefits. This study is to investigate the feasibility of the assessment elements consisting of framework for making a diagnosis of the level of administration innovation of local government. The elements of framework are such seven elements as innovative leadership, innovation vision and strategies, systematic infrastructure, innovative problems, innovation management, education and learning of innovation, and the perceptual level of members. The research results can provide the implications to not only local governments but also the public policy organizations who wish to extract the innovative problems and diagnose the innovation level of themselves.

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Fault Prediction and Diagnosis Using Fuzzy Expert System (퍼지 전문가 시스템을 이용한 고장 예측 및 진단)

  • 최성운;이영석
    • Journal of the Korea Safety Management & Science
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    • v.1 no.1
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    • pp.7-17
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    • 1999
  • As the loss from break-downs and errors, which became more frequent with the growth of elaborateness, complexity and in scale of the plant and equipments, are enormous, the improvement in the reliability, maintenance, safety, and qualify become to have interest. The fault diagnosis is a systematic and unified method to find errors, which is based on the interpretation that data, subconsciously, have noises. But, as most of the methods are inferences based on binomial logic, the uncertainty is not correctly reflected. In this study, we suggest, to manage the uncertainty in the system efficiently on the point of predictive maintenance, We should use fuzzy expert system, which make the decision considering uncertainty possible by taking linguistical variable and fixed quantity by using the fuzzy theory concepts on the basis of an expert's direct observation and experience.

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What is Evidence-based Dentistry?

  • Park, Livingstone Sang
    • Journal of Korean Dental Science
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    • v.3 no.2
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    • pp.34-39
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    • 2010
  • In our daily practice, we think about the diagnosis of our patient and get into a situation wherein we have to make a clinical decision. Diagnosis and treatment come from the knowledge and experiences that each dentist should have, but sometimes, we can have doubts on our decisions. "On what evidence did I make such decision? Was that really right?" Drawing our attention these days as a possible answer to this question, evidence-based dentistry seeks to apply the best available evidence gained from the scientific method to medical decision making. To make a good decision, the strength of evidence is assessed. Specifically, randomized controlled trial, systematic review, and meta-analysis are considered the highest level of evidence; cohort study, case control study, case series, animal study, bench test, and biological plausibility follow. With the approach of evidence-based dentistry, we can make objective, scientifically sound clinical decisions. It is also patient-oriented, incorporating clinical experiences and stressing good judgments; thorough and comprehensive, it uses transparent methodology. That is the reason evidence-based dentistry can be better than other assessment methods when we make a clinical decision in modern dentistry.

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Two New Records of Sac Spiders including a New Species (Araneae: Clubionidae) from Korea

  • Jang, Chang Moon;Bae, Yang Seop;Yoo, Jung Sun;Lee, Sue Yeon;Kim, Seung Tae
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.4
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    • pp.330-334
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    • 2021
  • The genus Clubiona Latreille, 1804 is the most diverse and largest one in the family Clubionidae Wagner, 1887. Twenty-nine species of the genus have been described in various ecosystems from Korea to date. Clubiona semicircularis Tang, Song and Zhu, 2005 which was formerly only known in China and Clubiona ansa n. sp. were collected with a sweep net on the foliage of the shrubs in mixed forests from mountains and agricultural landscape during a seasonal survey of the spider fauna in Korea. This study describes these two species with a diagnosis, measurements, and morphological illustrations. In addition, the female of C. semicircularis is described with a diagnosis for the first time from the present study.