• 제목/요약/키워드: Diagnostic system

검색결과 2,361건 처리시간 0.027초

신경망을 이용한 회전축의 이상상태 진단에 관한 연구 (A Study on the Neural Network Diagnostic System for Rotating Machinery Failure Diagnosis)

  • 유송민;박상신
    • Tribology and Lubricants
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    • 제16권6호
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    • pp.461-468
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    • 2000
  • In this study, a neural network based diagnostic system of a rotating spindle system supported by ball bearings was introduced. In order to create actual failure situations, two exemplary abnormal status were made. Out of several possible data source locations, ten measurement spots were chosen. In order to discriminate multiple abnormal status, a neural network system was introduced using back propagation algorithm updating connecting weight between each nodes. In order to find the optimal structure of the neural network system reducing the information sources, magnitude of the weight of the network was referred. Hinton diagram was used to visually inspect the least sensitive weight connecting between input and hidden layers. Number of input node was reduced from 10 to 7 and prediction rate was increased to 100%.

이중구조를 갖는 제어시스템의 구현과 신뢰도 분석에 관한 연구 (A Study on the Implementation of a Control System with Dual Structure and Its Reliability Analysis)

  • 박세화;문봉채;김병국
    • 대한전자공학회논문지
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    • 제27권9호
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    • pp.1351-1363
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    • 1990
  • In this paper, a reliable control system structured with dual CPU modules and dual I/O modules is implemented as a means of achieving a highly reliable fault tolerant control system. For this, faults in the system modules are first examined, and a fault detection technique consisting of self diagnostic, comparison process, and exception processing is applied. Self diagnostic is used to locate which components in the modules have been failed, while comparison process is to cmpare control outputs computed by both CPU modules and protect the plant from malfunction by blocking failed control outputsin advance. Finally exception processing is used to determine the faults that are not detected immediately by the self diagnostic and comparison process, e.g. bus error processing when acknowledge signal for data transfer is not activeted in the I/O modules. Also reliability analysis is conducted for the discrete time Markov model with dual structure. It is shown quantitatively that the reliability is improved in the control system with dual structure in comparison with a system with single module structure.

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Intelligent Data Reduction Algorithm for Sensor Network based Fault Diagnostic System

  • Youk, Yui-Su;Kim, Sung-Ho;Joo, Young-Hoon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제9권4호
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    • pp.301-308
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    • 2009
  • In the modern life, machines are used for various areas in industries as the advance of science and industrial development has proceeded. In many machines, the rotating machines play an important role in many processes. Therefore, the development of fault diagnosis and monitoring system for rotating machines is required. An ubiquitous sensor network (USN) is a combination of the key computer science and engineering area technology including the wireless network, embedded system hardware and software, communication, real-time system, etc. It collects environmental information to realize a variety of functions. In this work, a data reduction algorithm for USN based remote fault diagnostic system which can be easily applied to previously built factories is proposed. To verify the feasibility of the proposed scheme, some simulations and experiments are executed.

Automotive Diagnostic Gateway using Diagnostic over Internet Protocol

  • Lee, Young Seo;Kim, Jin Ho;Jeon, Jae Wook
    • IEIE Transactions on Smart Processing and Computing
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    • 제3권5호
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    • pp.313-318
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    • 2014
  • Recently, Ethernet-based Diagnostic Over Internet Protocol (DoIP) was applied to automotive systems, and in-vehicle gateways have been introduced to integrate Ethernet with traditional in-vehicle networks, such as the local interconnect network (LIN), controller area network (CAN) and FlexRay. The introduction of in-vehicle gateways and of Ethernet based diagnostic protocols not only decreases the complexity of the networks, but also reduces the update time for ECU software reprogramming while enabling the use of a range of services, including remote diagnostics. In this paper, a diagnostic gateway was implement for an automotive system, and the performance measurements are presented. In addition, a range of applications provided by the diagnostic gateway are proposed.

한방신경정신과 영역에서 진단기기의 활용 현황 (Present Application Status of Diagnostic Equipment in Clinical Studies in the Journal of Oriental Neuropsychiatry)

  • 이승기
    • 동의신경정신과학회지
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    • 제23권4호
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    • pp.1-10
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    • 2012
  • Objectives : This study aims to evaluate the current status of clinical use of diagnostic equipment in oriental neuropsychiatry. Methods : Thirty clinical studies using diagnostic equipment out of 223 papers in the journal of oriental neuropsychiatry in the 10 years from 2003 to 2012 were reviewed. Results : Ten diagnostic apparatuses were used in 30 papers. HRV (Heart Rate Variability) was used the most, but the results of papers were not consistent. ADS (ADHD Diagnostic System) and ERP (Event Related Potential) were effective in clinical research. Conclusions : Diagnostic equipment might be useful and effective to treat mental disorders if they are to be used properly and followed by well-designed studies.

Radiologic Findings of Renal Hemangioma: Report of Three Cases

  • Hak-Soo Lee;Byung-Hee Koh;Jang-Wook Kim;Yong-Soo Kim;Hyun-Chul Rhim;On-Koo Cho;Chang-Kok Hahm;Young-Nam Woo;Moon-Hyang Park
    • Korean Journal of Radiology
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    • 제1권1호
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    • pp.60-63
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    • 2000
  • Renal hemangioma is an uncommon benign tumor which usually causes painless or painful gross hematuria. Its preoperative diagnosis is extremely difficult or even impossible. We experienced three cases of renal hemangioma, located mainly at the pelvocalyceal junction or in the inner medulla. US demonstrated variable echogenecity, and CT revealed a lack of significant enhancement. Where there is gross hematuria in a young adult, especially when the renal mass located in the pelvocalyceal junction or inner medulla shows little enhancement on CT, renal hemangioma should form part of the differential diagnosis.

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지능형 풍력발전 기계적 요소 고장진단 시스템 개발 (Development of intelligent fault diagnostic system for mechanical element of wind power generator)

  • 문대선;김성호
    • 한국지능시스템학회논문지
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    • 제24권1호
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    • pp.78-83
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    • 2014
  • 최근 신재생 에너지원으로서의 선두주자인 풍력발전은 다수의 풍력발전 회사들로 하여금 모니터링 및 고장진단 시스템의 개발을 가속화시키고 있다. 이러한 모니터링 및 진단시스템은 조기의 고장검출을 통해 고장이 발생되었을 경우 발생되는 고가의 수리비용을 미연에 방지할 수 있게 한다. 일반적으로 풍력발전과 관련된 고장진단 시스템은 진동신호 및 신호분석기법에 기반하고 있다. 이에 본 연구에서는 풍력발전 시스템에서 자주 발생되고 있는 질량 불평형 및 축 정렬 불량 등과 같은 기계적인 고장을 효율적으로 진단할 수 있는 시스템을 제안하고자 한다. 본 연구에서 제안된 지능화된 고장진단 알고리즘은 인공신경망기법과 웨이블렛 변환을 이용한 것으로 (주)가온솔루션에서 개발한 풍력발전용 기계적 고장발생 장치에 적용 실험을 통해 제안된 진단기법의 유용성을 확인하고자 하였다.

담적의 진단요소 및 증후군으로서의 가치에 대한 문헌고찰 (A Literature Study on the Diagnostic Factors and Value as a Syndrome of Damjeok)

  • 임윤서;노기환;최규호;이상현;최서형
    • 대한한의학회지
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    • 제44권3호
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    • pp.170-188
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    • 2023
  • Objectives: The purpose of this study is to investigate the diagnostic factors of Damjeok in the literature. Methods: This study used the databases of five (Mediclassics, RISS, KMbase, OASIS, CNKI) to analyze diagnostic factors of Damjeok. Literatures published by May 2023 were assessed and we classified 91 literatures dealing with diagnostic factors by 5 categories, 'characteristics', 'location', 'symptom', 'pulse wave & tongue feature', and 'eating habits & lifestyle'. Results: Damjeok is mainly formed at the stomach in the form of lump or hard seed, and it can be observed in other regions or even the whole body by its trait of floating. Damjeok mainly shows symptoms of the digestive system and also causes various symptoms associated with the respiratory system and infection, musculoskeletal system, urogenital system, neuropsychiatric system and cardiovascular system. Regarding pulse wave and tongue feature, a slippery wave and greasy coated tongue are typical features of Damjeok. Additionally, bad eating habits and a lack of exercise have been described as a factor that cause and aggravate Damjeok. Conclusions: The two most important factors in the diagnosis of Damjeok are abdominal stiffness by physical examination and digestive symptoms, and these correspond to the definition of a syndrome. Diagnostic factors based on literature evidence will provide clues to the clinical diagnosis of Damjeok syndrome.

진단용 엑스선 장치에 있어서 방사선 방어에 대한 일반 요구사항 -IEC 60601-1-3:2008에 근거한 KFDA DRS 1-1-3:2008- (General Requirements Pertaining to Radiation Protection in Diagnostic X-ray Equipment -KFDA DRS 1-1-3 : 2008 base on IEC 60601-1-3:2008-)

  • 강희두;동경래;권대철;최준구;정재호;정재은;류영환
    • 대한디지털의료영상학회논문지
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    • 제11권2호
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    • pp.69-77
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    • 2009
  • This study gives an account of the collateral standards in IEC 60601-1-3: 2008 specifying the general requirements for basic safety and essential performance of diagnostic X-ray equipment regarding radiation protection as it pertains to the production of X-rays. The collateral standards establish general requirements for safety regarding ionization radiation in diagnostic radiation systems and describe a verifiable evaluation method of suitable requirements regarding control over the lowest possible dose equivalent for patients, radiologic technologists, and others. The particular standards for each equipment can be determined by the general requirements in the collateral standard and the particular standard is followed in the risk management file. The guidelines for radiation safety of diagnostic radiation systems is written up in ISO 13485, ISO 14971, IEC 60601-1-3(2002)1st edition, medical electric equipment part 1-3, and the general requirements for safety-collateral standards: programmable electrical medical systems. Therefore the diagnostic radiation system protects citizens' health rights with the establishment and revisions of laws and standards for diagnostic radiation systems as a background for the general requirements of radiation safe guards applies, as an international trend, standards regarding the medical radiation safety management. The diagnostic radiation system will also assure competitive power through a conforming evaluation unifying the differing standards, technical specifications, and recognized processes.

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회귀진단을 위한 새로온 척도의 제안 및 상호비교 (A Comparision of Diagnostic Measures in Linear Regression)

  • 최성운
    • 산업경영시스템학회지
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    • 제15권25호
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    • pp.103-113
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    • 1992
  • This paper is to study the various diagnostic measures for detecting outliers and influential cases in linear regression. In this paper we review the most common diagnostic measures and show the inter-relationships the exist among them. Based on the PRESS(Predicted REsidual Sum of Squares ) offered by Allen(1974) as a criterion for model selection, we propose three measures for detecting outliers and influential cases. Examples are given illustrating various diagnostic measures including Proposed measures.

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