• 제목/요약/키워드: resistance diagnosis

검색결과 304건 처리시간 0.03초

철도차량 견인전동기의 가속열화수명평가 기술현황 (A technology State of Accelerating Degradation and Life Estimation on the Traction Motor for Railway Rolling Stock)

  • 왕종배;김기준;최영찬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
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    • pp.25-28
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    • 2000
  • In this paper, the technology for accelerating degradation & life estimation on the traction motor was introduced with the stator form-winding sample coils of the 200 Class insulation system The accelerative degradation was performed in 10 cycles, which were composed of thermal stress, fast rising surge voltage, vibration, water immersion and overvoltage applying. After aging of 10 cycles, condition diagnosis test such as insulation resistance & polarization index, capacitance & dielectric loss and partial discharge properties were investigated in the temperature range of $20{\sim}160^{\circ}C$. Relationship between degradation conditions and diagnosis results were analyzed to find an dominative degradation factor at the end-life point

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가공공정의 이상상태진단을 위한 진단전문가시스템의 개발 (Development of Diagnostic Expert System for Machining Process Ffailure Detection)

  • 유송민;김영진
    • 한국정밀공학회지
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    • 제14권11호
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    • pp.147-153
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    • 1997
  • Fault diagnosis technique in machining system which is one of engineering techniques absolutely necessary to automation of manufacturing system has been proposed. As a whole, diagnosis process is explained by two steps: sensor data acquisition and reasoning current state of system with the given sensor data. Flexible disk grinding process implemented in milling machine was employed in order to obtain empirical manufacturing process information. Resistance force data during machining were acquired using tool dynamometer known as sensor which is comparably accurate and reliable in operation. Tool status during the process was analyzed using influnece diagram assigning probability from the statistical analysis procedure.

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하이브리드 FRP보강근 콘크리트의 손상 자가진단 (Self- Diagnosis of Damage in Hybrid FRP Reinforced Concrete)

  • 박석균;김대훈
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.233-237
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    • 2005
  • For giving self-diagnosing capability, a method based on monitoring the changes in the electrical resistance of hybrid FRP reinforced concrete has been tested. Then after examining change in the value of electrical resistance of carbon fiber in CFRP, CFGFRP, CFAFRP and e.t.c., before and after the occurrence of cracks and fracture in hybrid FRP reinforced concrete at each flexural weight-stage, the correlations of each factors were analyzed. As the results, it is clarified that when the carbon fiber tows fracture, the electrical resistance of it increase largely, and afterwards hybrid FRP composites can be resist the load due to the presence of the reinforced fiber, for example, glass fiber or aramid fiber tows.

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발전소 직류전선로의 지락안전진단 시스템에 관한 연구 (A Study on the Ground Fault Diagnosis System of Power Station DC Power line)

  • 안영주;김남호;이형기
    • 한국안전학회지
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    • 제12권1호
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    • pp.37-43
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    • 1997
  • There are two kinds of ground fault diagonosis system(GFD), which are for AC and DC power line. The ground fault current of a DC power line Is, first, analyzed for a description of a GFD system for DC power line and then the construction method of the GFD system, which could be processed and analyzed a ground fault current, are explained. Main functions of the system are that the detected ground fault current could be converted to the line insulation resistance by a program and saved in the system memory continuously. Finally a DC power line insulation safety could be decide by a change of the saved Insulation resistance for a given time. This system can detect the ground fault resistance to 100㏀.

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산업용 이차전지의 열화판정에 관한 연구 (A Study on Degradation Diagnosis of Secondary Battery)

  • 남종하;태용준;여인영;최진홍;천창열;김재웅
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2005년도 전력전자학술대회 논문집
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    • pp.170-172
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    • 2005
  • Internal battery ohmic measurements have been a hot topic amongst battery users and battery manufacturers. As a battery deteriorates and loses its capacity, the internal resistance of the battery increases. Everyone seems to agree that measuring the internal parameters of a cell can be very useful in determining a battery's state of health. In this paper experiences show that if a cell's resistance increases by more than25% above its baseline value(known good resistance of new 100% capacity cell), the cell will no loger be able to deliver 80% or more of the rated capacity.

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경년변화에 따른 송전용 폴리머 현수애자의 트래킹 성능평가 (Tracking Property of Polymer Suspension Insulator for Transmission line with secular variation)

  • 조한구;이운용;이유정;임기조;최인혁
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.558-559
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    • 2005
  • Recently, polymer insulators that are used for high voltage applications have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. During outdoor service of polymer insulators, the surface of the insulating material is frequently subjected to moisture and contamination that lead to dry band arcing. Their tracking resistance, erosion resistance, end sealing and shed design are very important because dry band arcing causes degradation of polymer surface. In this paper, the tracking property of polymer suspension insulator for power transmission is investigated with CEA tracking wheel test. The diagnosis of insulator sample in tracking test has been analyzed by leakage current, STRI Guide, SEM, FTIR and thermal image.

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Diagnosis and treatment of multidrug-resistant tuberculosis

  • Jang, Jong Geol;Chung, Jin Hong
    • Journal of Yeungnam Medical Science
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    • 제37권4호
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    • pp.277-285
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    • 2020
  • Tuberculosis (TB) is still a major health problem worldwide. Especially, multidrug-resistant TB (MDR-TB), which is defined as TB that shows resistance to both isoniazid and rifampicin, is a barrier in the treatment of TB. Globally, approximately 3.4% of new TB patients and 20% of the patients with a history of previous treatment for TB were diagnosed with MDR-TB. The treatment of MDR-TB requires medications for a long duration (up to 20-24 months) with less effective and toxic second-line drugs and has unfavorable outcomes. However, treatment outcomes are expected to improve due to the introduction of a new agent (bedaquiline), repurposed drugs (linezolid, clofazimine, and cycloserine), and technological advancement in rapid drug sensitivity testing. The World Health Organization (WHO) released a rapid communication in 2018, followed by consolidated guidelines for the treatment of MDR-TB in 2019 based on clinical trials and an individual patient data meta-analysis. In these guidelines, the WHO suggested reclassification of second-line anti-TB drugs and recommended oral treatment regimens that included the new and repurposed agents. The aims of this article are to review the treatment strategies of MDR-TB based on the 2019 WHO guidelines regarding the management of MDR-TB and the diagnostic techniques for detecting resistance, including phenotypic and molecular drug sensitivity tests.

13[kV]급 수력발전기 고정자 권선의 운전 및 정지 중 진단시험 현장적용 평가 및 분석 (Site Evaluation and Application of the On-line and Off-line Test for the 13[kV] Class Hydropower Generator Stator Windings)

  • 장정호;이동근;이흥호
    • 조명전기설비학회논문지
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    • 제25권11호
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    • pp.73-82
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    • 2011
  • The solid insulation system of stator windings in high voltage rotational machines is usually aging in accordance with long time operation. The partial discharge test have been known to check whether insulation deterioration exist or not, and the PD test can effectively diagnose a solid insulation condition regardless of during operation(on-line) or not(off-line). The on-line PD measurement have proven to be a successful technique in monitoring stator insulation condition nowadays. This paper describes the characteristics of comparing the on-line PD measurement data using PDMS-HG(Partial Discharge Monitoring System for Hydro-electric Generator) installed in field with the off-line diagnosis measurement data(insulation resistance, winding resistance, PI, ${\Delta}tan{\delta}$ and PD) on hydro generator(13[kV]) stator windings. These results make good use of managing rotational machines through evaluating the solid insulation condition of stator windings.

Consideration in treatment decisions for refractory Mycoplasma pneumoniae pneumonia

  • Cho, Hye-Kyung
    • Clinical and Experimental Pediatrics
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    • 제64권9호
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    • pp.459-467
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    • 2021
  • Mycoplasma pneumoniae (MP) is the most common cause of childhood bacterial pneumonia. Although macrolide is known to be effective as a first-line therapy, the proportion of macrolide resistance in MP pneumonia has strikingly increased during recent 2 decades in East Asia. This is challenging to physicians since they have to decide more often whether to use secondary treatment. Diagnostic methods to detect macrolide-resistance of MP are currently not available in Korean hospitals. Even in the diagnosis of MP infection, both serologic and molecular test have limitation: inability to differentiate current illness from carriage or asymptomatic infection. Combining these 2 diagnostic methods and excluding infection caused by other respiratory pathogens allow a more reliable diagnosis. This effort is even more demanding in recent years to keep children from unnecessary exposure to secondary antibiotics. Although several observational studies have reported that tetracycline and fluoroquinolone, which are considered in the treatment of refractory MP pneumonia, have efficacy of shortening the duration of fever and respiratory symptoms, those findings need to be proven by well-designed prospective studies. The use of tetracycline and fluoroquinolone in children is generally tolerable, as supported by many observational data. However, since concerns about side effects still remain, careful consideration about benefits and risks is needed to decide their use.

재가 정신질환자의 내재화된 낙인, 삶의 의미와 정신건강회복과의 관계 (Association of Mental Health Recovery to Internalized Stigma and Meaning in Life of Community-Dwelling People with Mental Disorder)

  • 김주연;전원희
    • 가정∙방문간호학회지
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    • 제26권2호
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    • pp.189-198
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    • 2019
  • Purpose: The purpose of this study was to investigate the associations of mental health recovery to internalized stigma and meaning in life of community-dwelling people with mental disorder. Methods: Participants were 150 people with mental disorder who were enrolled at one of the community mental health institutions in D, S, and U cities, South Korea. Data analyses included a descriptive analysis, t-tests, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression using SPSS 25.0 software. Results: There were significant mean differences in mental health recovery according to education, religion, residential status, diagnosis, and day program use status of people with mental disorder living in the community. The significant predictors of mental health recovery included presence of meaning, stigma resistance, diagnosis (Major depressive disorder), and search for meaning. The regression model explained 58.7% of mental health recovery. Conclusion: Improving meaning in life and stigma resistance will increase the chances of mental health recovery among community- dwelling people with mental disorder.