• Title/Summary/Keyword: structural diagnosis

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A Study on Stability of Cracked Main Structure in Subway (균열발생 지하철 본선구조물의 안정성 연구)

  • Woo, Jong-Tae;Yhim, Sung-Soon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.3 no.3
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    • pp.187-194
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    • 1999
  • In this study, a series of items on the safety and stability of cracked main structure in subway are investigated and analyzed. Cracks due to dry contraction under the construction can be found when a tensile stress of cross section is higher than tensile strength at a value of coefficient of dry contraction $200{\times}10^{-6}$. It is concluded that there is no problems when load carrying capacity, that is, an ability of resisting loads of structure is enough in this analytical model. Also, it is concluded that this model has a desirable serviceability because a width of bending crack is lower than allowable one.

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화재를 당한 콘크리트 구조물의 내구성 진단

  • Seo, Chi-Ho
    • Fire Protection Technology
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    • s.18
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    • pp.17-20
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    • 1995
  • A diagnosis the concrete structure suffered a fire has an end in the view of safe investigation of structures and judgement of the re-use for the existing facilities to close examination of structural resisting forces and the extent of damages. And then, in this report, it has an object of references needed to fit management of concrete struc-ture suffered a fire, with describing epitome of conerete crack examination, displacement strain investi-gation, stregth examination, steel bar probing & carbonation test.

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Recent Advancement in Renal Replacement Therapy

  • Ota, Kazuo
    • Journal of Biomedical Engineering Research
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    • v.5 no.2
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    • pp.121-126
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    • 1984
  • A new approach to texture classification for quantitative ultrasound liver diagnosis using run difference matrix was developed. The run difference matrix comprised the gray level difference along with a distances. From this run difference matrix, we defined several vectors and parameters such as DOD, DGD, DAD vector, SHP, SMO, SMG, LDE, LDEL etc.Each parameter values calculated in fatty, cirrhotic, normal and chronic hepatitic liver images were plotted in a plane and we found that RDM method was more sensitive to small structural changes than the conventional run length method and showed improved classification ability between the diseases.

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Transformer Vibration Analysis for a variation of Load (부하변화에 대한 변압기 진동 분석)

  • 강창구;곽희로;정찬수;조국희;권혁승
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1993.10a
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    • pp.103-106
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    • 1993
  • This paper describes the modeling of winding vibration for a variation of load and temperature. The structural changes in transformer windings due to heat cause the change of vibration patterns. The vibration signals were detected by the accelerometer on the transformer windings. The real values were compared with estimated value using least-squares method, vibration model was cstablished and with this model, error compared with original signal was less than -50[db]. These results could be applied to diagnosis of incipient failures of the power transformers.

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A study about an old age car performance characteristic (노후차량 성능 특성에 관한 연구)

  • Hong Yong-Ki;Kwon Sung-Tae
    • Proceedings of the KSR Conference
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    • 2005.11a
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    • pp.332-337
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    • 2005
  • In order to investigate performance changes, the acceleration, vibration, and braking performance tests were carried out on the electric multiple units (EMUs) with over 20 years operation. According to the testing results, in vibration and braking performance, the similar performance results were obtained as compared with newly manufactured EMUs. However, in terms of acceleration performance, below reference value (3.0 km/h/s) has been obtained. This is mainly due to performance deterioration including traction motor. The precision diagnosis evaluation of deteriorated EMUs will be provided through the overall evaluation of corrosion testing and structural performance of car body.

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FUZZY METHOD FOR FINDING THE FAULT PROPAGATION WAY IN INDUSTRIAL SYSTEMS

  • Vachkov, Gancho;Hirota, Kaoru
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1114-1117
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    • 1993
  • The paper presents an effective method for finding the propagation structure of the real origin of a system malfunction. It uses a combined system model consisting of Structural Model (SM) in the form of Fuzzy Directed Graph and Behavior Model (BM) as a set of Fuzzy Relational Equations $A\;{\circ}\;R\;=\;B$. Here a specially proposed fuzzy inference technique is checked and investigated. Finally a test example for fault diagnosis of an industrial system is given and analyzed.

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An Efficient Modeling Method for Open Cracked Beam Structures (열린 균열이 있는 보의 효율적 모델링 방법)

  • Kim, M. D.;Park, S. W.;S. W. Hong;Lee, C. W.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.372.2-372
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    • 2002
  • This paper presents an efficient modeling method fur open cracked beam structures. An equivalent bending spring model is introduced to represent the structural weakening effect in the presence of open cracks. The proposed method adopts the exact dynamic element method (EDEM) to avoid the difficulty and numerical errors in association with re-meshing the structure. The proposed method is rigorously compared with a commercial finite element code. (omitted)

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Measuring the Factors Mediating the Effect of Food Involvement on Fruit Consumption (과일 소비에 미치는 음식 관여도의 영향을 매개하는 요인 평가)

  • Kang, Jong-Heon;Jeong, Hang-Jin
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.2
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    • pp.172-180
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    • 2008
  • The purpose of this study was to measure the causal relationships among food involvement, health, mood, convenience, sensory appeal, weight control, and fruit consumption. A total of 290 questionnaires were completed. A structural equation model was used to measure the causal effects of the constructs, and the structural analysis results for the data indicated an excellent model fit. The effects of food involvement on health, mood, convenience, sensory appeal, weight control, and fruit consumption were statistically significant. As expected, health, mood, and weight control had significant effects on fruit consumption. Moreover, food involvement had a significant indirect effect on fruit consumption through health, mood, convenience, sensory appeal and weight control. For the future development and testing of conceptual models that integrate the relationships among personality traits, food choice motives, and fruit consumption, this study may approach a deeper understanding of the complex relationships among fruit consumption behavior-related variables. Greater understanding of these complex relationships can improve the managerial diagnosis of the problem and opportunities for different marketing strategies, including fruit production and fruit product development and marketing communications.

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