• 제목/요약/키워드: Deterioration Diagnosis

검색결과 349건 처리시간 0.027초

태안마애삼존불의 보존과학적 훼손도 진단과 보존환경 분석 (Analysis of Conservation Scientific Deterioration Diagnosis and Conservation Environment of the Samjonbul Carved on Rock Surface in Taean, Korea)

  • 엄두성;전병규;한민수;이장존;송치영
    • 보존과학연구
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    • 통권29호
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    • pp.19-44
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    • 2008
  • Sam-jon-bul or Three Buddha Image Carved on rock surface which is called Sam-jon-bul in Taean, state-designated national treasure No. 307, made in Baek-je Period, has two Buddha images and one Bodhisattva. The detached part of the Sam-jon-bul from wall rock has been attached through conservation treatment in 1995. Few study has been done on weathering condition of petrological point of view and damage while the surface of the Sam-jon-bul has been under serious weathering (relief) of loosing stone particles, and discoloration. In this study, it was made weathering damage maps, which show physical property of the material and state of damage of Sam-jon-bul, in order to dialogize how far the weathering has been done. It has been considered continuing on-site monitoring as necessity when Sam-jon-bul was covered with dew, which may have been caused by change in weather in and out of the protect building. It is necessary to set up detailed conservation plan for it by doing regular diagnosis on the influence of the protect building and weathering of Sam-jon-bul.

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Rapid Atypical Progression of Neuro-Behçet's Disease Involving Whole Brainstem and Bilateral Thalami

  • Lee, Sang-Kook;Choi, Sung-Jae;Kim, Sang-Dae;Lim, Dong-Jun
    • Journal of Korean Neurosurgical Society
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    • 제50권1호
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    • pp.68-71
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    • 2011
  • We present a case of Neuro-Behçet's disease with an unpredictable clinical course. A 47-year-old man was admitted to the neurosurgery department of our hospital with a mild headache. Three days after admission, his consciousness suddenly decreased and respiratory distress progressed rapidly. A brain MRI revealed that the previously observed abnormal signal had extended markedly to both the thalamic areas and the entire brain stem, and the surrounding brain parenchyma were compressed by cerebral edema. Based on the patient's symptoms of recurrent oral and genital ulcers, skin lesions, and uveitis, a rheumatologist made a diagnosis of Behçet's disease with CNS involvement. The patient was treated with high-dose methylprednisolone with respiratory assistance in the intensive care unit for 9 days and his neurologic symptoms improved remarkably. Neuro-Behçet's disease must be considered in the differential diagnosis in rapidly deteriorated young neurological patients along with a stroke, low-grade glioma, multiple sclerosis, and occlusive venous disease.

열화상 이미지를 이용한 배전 설비 검출 및 진단 (Detection and Diagnosis of Power Distribution Supply Facilities Using Thermal Images)

  • 김주식;최규남;이형근;강성우
    • 대한안전경영과학회지
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    • 제22권1호
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    • pp.1-8
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    • 2020
  • Maintenance of power distribution facilities is a significant subject in the power supplies. Fault caused by deterioration in power distribution facilities may damage the entire power distribution system. However, current methods of diagnosing power distribution facilities have been manually diagnosed by the human inspector, resulting in continuous pole accidents. In order to improve the existing diagnostic methods, a thermal image analysis model is proposed in this work. Using a thermal image technique in diagnosis field is emerging in the various engineering field due to its non-contact, safe, and highly reliable energy detection technology. Deep learning object detection algorithms are trained with thermal images of a power distribution facility in order to automatically analyze its irregular energy status, hereby efficiently preventing fault of the system. The detected object is diagnosed through a thermal intensity area analysis. The proposed model in this work resulted 82% of accuracy of detecting an actual distribution system by analyzing more than 16,000 images of its thermal images.

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.

과도서지를 이용한 가속열화 시험법에 따른 견인전동기 고정자 코일의 전기적 특성 변화 (Properties of Electrical Performance on Stator Coil of Traction Motor by Accelerated lest using Transient Surge)

  • 박현준;장동욱;이길헌;최종선;김저우
    • 한국전기전자재료학회논문지
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    • 제16권9호
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    • pp.783-789
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    • 2003
  • The winding problems of traction motor are the major determinant of motor's life. The root cause of winding failure is gradual deterioration of the insulation due to thermal, electrical, mechanical and environmental stresses. The aging of the insulation reduces the electrical and mechanical strength of the insulation. At same point, a voltage surge or mechanical shock from a traction motor start will fracture or break down the insulation. To achieve the expected life usually requires extensive laboratory evaluation of the insulation systems and the use of accelerated aging tests. There are several nondestructive test available for checking, the condition of motor insulation, the probable extent of aging, and the rate of which aging is taking place. So the insulation characteristics of stator coil were each analyzed by measurement of dielectric loss(tan$\sigma$), capacitance and partial discharge. The method of diagnosis is able to analyze the insulation condition and evaluate the life of the traction motor.

피뢰기 누설전류 분석장치를 이용한 ZnO 피뢰기의 누설전류 변화 분석 (The Leakage Current Analysis of ZnO Arrester Using Leakage Current Dete)

  • 김영춘;문선호;오정환;김재철;이영길
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.1082-1084
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    • 1998
  • In this paper, we developed a diagnosis device for ZnO arrester to detect on-line leakage current and acquire data from the power distribution system. The arrester is important power equipment used in power transmission and distribution systems to protect the generator and the main transformer from surge and overvoltage. First of all we developed a diagnosis device for ZnO arrester leakage current. And then we detect the total leakage current by the developed device without disconnecting the arrester ground wire and analysis the 3rd order harmonic by Fast Fourier Transform(FFT) to diagnose the ZnO arrester deterioration. With measuring the total current and the resistive current of power distribution system in operation, we analysis the trend of resistive current component in the total leakage current. We expect the result will be promote the method to protect electrical utility and customer from accident.

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Measurement Method of the Resistive Leakage Current for Lightning Arrester Diagnosis

  • Kil, Gyung-Suk;Han, Ju-Seop;Song, Jae-Yong;Seo, Hwang-Dong
    • Transactions on Electrical and Electronic Materials
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    • 제6권2호
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    • pp.63-66
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    • 2005
  • Several ways for monitoring the soundness of ZnO lightning arresters have been suggested, and all of which are based on the measurement of leakage current since it is well known that the resistive leakage current is a main indicator of arrester deterioration. In this paper, we proposed an algorithm to measure the resistive leakage current, which is quite different from the conventional method that eliminates capacitive current from the total leakage current. The proposed algorithm is based on that the magnitudes of the resistive leakage current are equal at the same applied voltage levels. To confirm the reliability of the algorithm, we fabricated a leakage current detector and designed an analysis program. Experimental results showed that the method does not need a complex circuitry and is useful to analyze the resistive leakage current.

The Association between Health-related Quality of Life and Depression on Activity Restriction in Osteoarthritis: A Cross-sectional Study

  • Lee, Do-Youn;Kim, Seong-Gil
    • The Journal of Korean Physical Therapy
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    • 제32권6호
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    • pp.329-334
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    • 2020
  • Purpose: The purpose of this study is to provide basic evidence on the need to approach osteoarthritis patients through a psychological factors-considering rehabilitation program by understanding how activity restrictions in osteoarthritis affect health-related quality of life and depression. Methods: This study assessed 3,761 osteoarthritis patients from the Korea National Health and Nutrition Examination Survey. The subjects were divided into two categories: with and without activity restriction. Results: The prevalence of osteoarthritis in women was higher than that of men (men: 19.7%; women: 80.3%), and high BMI increased the prevalence of osteoarthritis. The EQ-5D index of subjects with activity restriction was 0.84±0.18 (points), while in those without activity restriction was 0.93±0.12, and the diagnosis of depression was 15.8%, 8.2%. There was a statistically significant difference in the odds ratio for each item in the EQ-5D. Moreover, the odds ratio for depression with activity restriction was 2.098 compared with no activity restriction. Conclusion: Activity restriction of osteoarthritis patients significantly decreases the health-related quality of life and increase the probability of depression. Therefore, early diagnosis of depression symptoms to prevent deterioration of symptoms in patients with osteoarthritis and to increase compliance with rehabilitation treatment, and to provide arbitration, including treatment that can alleviate depression.

A Study on Classifications and Characteristics of Declined Rural Area in Chungcheong Region

  • Jo, Jinhee;Park, Hyungkeun;Seo, Sedeok
    • 국제학술발표논문집
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    • The 6th International Conference on Construction Engineering and Project Management
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    • pp.468-471
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    • 2015
  • The study aims to identify the degree and types of spatial decline in Eup/Myun units within Chungcheong region in South Korea to contribute to the efforts being made to diagnose the rural decline and the potentials. To this end, we analyzed 27 Sis and Guns to identify the degree of decline and potentials of rural areas in Chungcheong region. We also carried out the diagnosis and K-Means Clustering on 274 Eups and Myuns, the smallest administrative units, to figure out the types and characteristics of the rural recessions. According to the results of the clustering analysis carried out on the 166 Eups and Myuns, there were five outstanding clusters. They were; areas with housing deterioration (29), areas with poor economic foundation (16), areas with poor accessibility to central areas (42), areas with poor residential environment (51) and areas with aged population (28). The findings and results of the present study are likely to serve as a basis for the design and enforcement of forthcoming rural area activation policies. Also, it would be highly recommended that a more comprehensive diagnosis is taken from a community-level perspective and policy suggestions and strategies tailored for rural communities are further discussed.

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슬관절 부위에서 자화전이 위상감도법에 의한 자화전이율 영상 평가 (Evaluation of Magnetization Transfer Ratio Imaging by Phase Sensitive Method in Knee Joint)

  • 윤문현;성미숙;최보영
    • 한국의학물리학회지:의학물리
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    • 제19권4호
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    • pp.269-275
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    • 2008
  • 슬관절 퇴행성 질환을 진단하기 위하여 자기공명영상(magnetic resonance imaging: MRI)이 많이 사용되지만 간혹 슬관절 병후 및 예후를 잘못 진단하는 경우가 종종 발생한다. 본 연구에서는 슬관절 질환의 진단에 도움을 주기 위하여 자화전이(magnetization transfer: MT) 영상법을 소개하고자 한다. 슬관절 환자 7명으로부터 스핀 에코(SE) T2 강조 영상(3,400-3,500/90-100 ms)과 슬관절 환자 7명으로부터 FSE T2 강조 영상(4,500-5,000/100-108 ms)과 또한 슬관절 환자 3명으로부터 gradient echo (GRE) T2 강조 영상들(9/4.56 ms, 50 flip angle, NEX 1)을 획득하였다. 6명의 슬관절 환자에서 지방 억제가능 T2 강조 STIR 펄스시퀀스(TR/TE=2894-3215 ms/70 ms, NEX 3, ETL 9)를 사용하였다. 지방 포화도에 있어서 위상감도 방법은 Larmor frequency 차이에 따른 위상 차이를 이용하므로, 각각의 픽셀에 대한 자화전이율(magnetization transfer ratio: MTR)의 측정은 포화된 영상과 포화되지 않은 영상의 비율에 따라 산출하였다. 따라서 각 입력된 영상들은 동차원성을 가지고, 시각적으로 신호강도 정도가 회색의 명암도만으로 평가될 수 있기 때문에 생리학적, 정량적 진단을 위하여 3차원 등방성 체적영상과 자기공명 삼원색을 매핑하였고 정량적 특정은 자화전이율 지도로서 표현하였다. 자화전이율 영상은 병변 부위에서 높은 대조도를 나타내어 환자의 병태를 추적하는데 도움을 주었고 정량화하였다. 자화전이율 영상들과 기존의 MRI 사이에 명암도 차이는 회색상으로 표현되며, 자화전이율 영상화의 효과에 대해 프로파일 그래프는 자화전이 펄스로 인하여 신호강도에 있어서 정량적 측정값이 상대적으로 감소하였다. 슬관절의 정확한 병리상태를 진단하기 위해 프로파일 그래프의 측정값을 영상과 함께 표현하였다. 본 연구에서 수행한 예비적 데이터들을 통하여 슬관절의 자화전이율 영상들이 매우 임상학적으로 유용함을 확인하였다. 자화전이율 영상에 대한 물리적 변화를 관찰함으로써 자화전이율 영상에 대한 물리적, 기술적 기반에 대한 더 많은 통찰력을 제공할 수 있다. 무릎 질환 환자의 자화전이율 영상들을 이용하여 매우 높은 대조도를 확보할 수 있으므로 슬관절 질환의 정밀 진단에 매우 도움을 줄 수 있다.

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