• Title/Summary/Keyword: Cause Analysis

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A Study on the Characteristic and Rising Cause of Sheath Circulating Current by Analysis and Measurement (해석 및 측정을 통한 시스순환전류 특성 및 상승원인 검토)

  • Gang, Ji-Won;Yang, Hae-Won
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.51 no.10
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    • pp.525-533
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    • 2002
  • It is common to install multiple lines in the same route. Recently, excessive sheath circulating current was partially measured in underground cable systems of KEPCO. Especially, the installation type, unbalance section length between joint boxes and zero sequence current by distribution cable have an effect on the rising of sheath circulating current in the underground transmission system. If excessive current flows in sheath, sheath loss which is reduced the transmission capacity is produced. This paper describes the relation analysis of sheath circulating current and burying types. And also, a detailed analysis on rising cause and characteristic of sheath circulating current by considering various unbalanced conditions presents using analysis and measurement regarding cable systems which have the problem of excessive sheath circulation current.

Utilizing GIS for Forecasting Fire Risk Cumi city (구미지역 산불위험도 예측을 위한 지리정보시스템의 활용)

  • Lee, Jin-Duk;Han, Seung-Hee;Sim, Jung-Bo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.371-373
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    • 2010
  • Gumi is surrounded by mountains and Provincial parks are located. A high risk of forest fires that cause the spread of damage effects, and is forecast to have forest fire prevention and Geumohsan Provincial Park to preserve the target Gumi analysis was likely to cause fires. Numerical analysis to the probability of fire, clinical way, even in land cover, using Arc Gis aspect, altitude, slope, watersheds, vegetation, soil characteristics were extracted. Logistic analysis to extract the data in pixels by dividing the number analysis of forest fire risk indices presented in Gumi.

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Scalable Approach to Failure Analysis of High-Performance Computing Systems

  • Shawky, Doaa
    • ETRI Journal
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    • v.36 no.6
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    • pp.1023-1031
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    • 2014
  • Failure analysis is necessary to clarify the root cause of a failure, predict the next time a failure may occur, and improve the performance and reliability of a system. However, it is not an easy task to analyze and interpret failure data, especially for complex systems. Usually, these data are represented using many attributes, and sometimes they are inconsistent and ambiguous. In this paper, we present a scalable approach for the analysis and interpretation of failure data of high-performance computing systems. The approach employs rough sets theory (RST) for this task. The application of RST to a large publicly available set of failure data highlights the main attributes responsible for the root cause of a failure. In addition, it is used to analyze other failure characteristics, such as time between failures, repair times, workload running on a failed node, and failure category. Experimental results show the scalability of the presented approach and its ability to reveal dependencies among different failure characteristics.

Performance Analysis of the Lubricating Oil Feed Pump by the Anslysis of the Flow Network (유로망 해석에 의한 윤활유 공급펌프 성능 해석)

  • Kil, Doo-Song;Lee, Young-Ho
    • Journal of Power System Engineering
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    • v.6 no.4
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    • pp.62-67
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    • 2002
  • In this paper, the cause of the discrepancy of the inlet and outlet flow of the lubricating oil feed pump was analyzed by the flow measurement and the analysis of the flow network. At first, we thought that the flow difference was induced by a leak in the middle of the flow network. But, through the flow measurement using ultrasonic flow meter and the performance analysis of the pump, we knew that the cause of the flow difference was due to a drop in efficiency of the pump according to the pressure drop of the outlet. Also, we knew that the shape of the piping had no effect on the efficiency of the pump.

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Development of the Defect Analysis Technology for CANDU Spent Fuel

  • Kim, Yong-Chan;Lee, Jong-Hyeon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.2
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    • pp.215-223
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    • 2021
  • The domestic CANDU nuclear power plants have been operated for a long time and various unforeseen spent fuel defects have been discovered. As the spent fuel defects are important factors in the safety of the nuclear power plant, a study on the analysis of the spent fuel defects to prevent their recurrence is necessary. However, in cases where the fuel rods inside the fuel assembly are defected, it is difficult to dismantle the fuel assembly owing to their welded structure and the facility conditions of the plant. Therefore, it is impossible to analyze the spent fuel defect because it is difficult to visually check the shape of the fuel defect. To resolve these problems, an analysis technology that can predict the number of defected fuel rods and defect size was developed. In this study, we developed a methodology for investigating the root cause of spent fuel defects using a database of the earlier fuel defects in the plants. It is anticipated that in the future this analysis technology will be applied when spent fuel defects occur.

Comments on a Case Study on Engineering Failure Analysis of Link Chain

  • Yu, George Y.H.
    • Safety and Health at Work
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    • v.12 no.4
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    • pp.544-545
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    • 2021
  • The article by Tae-Gu Kim et al. conducted elastic FE modeling, which was inappropriate for fracture of elastic-plastic chain material (11.3% of elongation). FE analysis results and the findings in the fracto-graphic analysis did not tally but contradicted each other. The article identified "incorrect installation"/bending forces as the root cause while FE results of the chain under bending forces showed very low stresses at fracture locations but the highest stress in the middle of shank of the chain. The article's "step-like topographies indicating the fracture due to bending moment rather than uniaxial tension" lacked scientific support. The load value carried by each chain section under bending/incorrect installation was only half of that under tension, thus the article using same load value in FE simulation comparison for bending and tension was incorrect. The real cause of the chain fracture was likely improper checking the lifted load or/and using the wrong chain with much lower safety working load.

Bone Spur and Over Weight in Painful Heel Syndrome and Tenderness, Underlying Cause Analysis (종골부 동통 증후군의 원인분석)

  • Ko, Sang-Hun
    • Journal of Korean Foot and Ankle Society
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    • v.2 no.2
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    • pp.76-81
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    • 1998
  • Chiefly, painful heel syndrome is observed at old age. Many possible reasons were bursitis, plantar fasciitis, calcaneal periostitis around the calcaneus and achilles tendon. But the exact cause was not clearly identified due to complexity of subcalcaneal pain mechanism. The incidence of calcaneal spur and overweight were significant in painful heel syndrome. Our purpose of this study was analysis of underlyng cause and correlation about bony spur and overweight in painful heel syndrome. The author used incidence of heel spur on painful heel syndrome and body mass index to evaluate overweight. The material is 55 cases of painful heel syndrome patients and 60 cases of control group. Bony spur was one of the cause of painful heel syndrome. Body weight and calcaneal spur was developing factors on painful heel syndrome. And the result was as follows. 1. Spur formation incidence is 35 cases (63.6 %) in painful heel syndrome, 8 cases (13.3%) in normal control group. So, patient's group is significantly high (p<0.01). 2. Body mass index is 26.48 in painful heel syndromes, 21.75 in normal control groups. Overweight above index 27 is 22 cases (40%) in painful heel syndromes, 3 cases (5%) m normal control groups. So, patient's group is significantly high (p<0.01). 3. In painful heel syndrome, tenderness site is 46 cases (83.6%) in medial calcaneal tuberosity, 4 cases (7.3%) in central calcaneal tuberosity, 1 cases (1.8%) in both site. 4. Underlying causes of painful heel syndrome is 19 cases (34.5%) in plantar fasciitis, 16 cases (29.1%) in calcaneal periostitis, 11 cases (20%) in bursitis, 4 cases (7.3%) in tendinitis, 2 cases (3.6%) in entrapment neuropathy.

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Moderate Aortic Stenosis in Patients With Heart Failure

  • Vien T. Truong;John Ernst;Akhil Pallerla;Amitesh Verma;Cheryl Bartone;Cassady Palmer;Eugene S. Chung
    • Korean Circulation Journal
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    • v.52 no.12
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    • pp.878-886
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    • 2022
  • Background and Objectives: Moderate aortic stenosis (AS) confers a surprisingly adverse prognosis, approaching that of severe AS. The objective of this study was to describe the clinical course of patients with moderate AS with evidence of concomitant heart failure manifesting as elevated brain natriuretic peptide (BNP) levels. Methods: This is a single-center, retrospective cohort study of 332 patients with elevated BNP. 165 patients with moderate AS were compared with 167 controls with none-mild AS. The Median follow-up duration was 3.85 years. The primary outcome was a composite endpoint of all-cause hospitalizations and all-cause mortality. Results: BNP levels were 530 and 515 pg/mL in the study and the control groups, respectively. Moderate AS had significantly higher rates of primary composite endpoint in both univariate analysis (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.14-1.97; p=0.004) and adjusted analysis (HR, 1.45; 95% CI, 1.05-2.01; p=0.02). Moderate AS had 1.41 (95% CI, 1.18-1.69; p<0.001) times more all-cause hospitalization per patient-year of follow-up compared to controls in the univariate model. After adjustment for significant covariates, moderate AS remained an independent predictor of all-cause hospitalizations (incidence rate ratio [IRR], 1.45; 95% CI, 1.18-1.79; p=0.005). Furthermore, moderate AS was significantly associated with higher all-cause hospitalization rates in both heart failure with reduced ejection fraction (IRR, 1.33; 95% CI, 1.02-1.75; p=0.038) and heart failure with preserved ejection fraction [IRR], 1.31; 95% CI, 1.03-1.67; p=0.026). Conclusions: Moderate AS in conjunction with elevated BNP portends a significantly worse prognosis than those without moderate AS and should be followed closely.

The Influence of Cause-Related Marketing on Consumer Attitude for Fashion Brand (패션브랜드의 공익연계마케팅이 소비자 태도에 미치는 영향)

  • Park, Kyunga;Hwang, Sunjin
    • Journal of Fashion Business
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    • v.16 no.5
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    • pp.130-145
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    • 2012
  • The purpose of this study is to investigate the influence of cause-related marketing on consumer attitude for fashion brand in terms of brand familiarity, consumer's propensity for data processing and types of advertising. The design of this study is comprised of 2(brand familiarity : high vs low)${\times}$ 2(consumer's propensity for data processing : high vs low), designed with three mixed elements. The subjects of this study are 308 male and females in twenties or thirties from the area of Seoul, Kyunggi, Busan and Daegu. Data analysis is carried out through T-test, and ANOVA. The results of this study are as follows. First, when fashion brand pursues cause-related marketing, brand familiarity, consumer's propensity for data processing and types of advertising have statistically interaction effect on consumer's preference. Second, rational appeals in advertising have no significant interaction effect on consumer's preference in terms of brand familiarity. Rational appeals are preferred to Emotional appeals in both familiar and unfamiliar brand. Third, when fashion brand pursue cause-related marketing, brand familiarity, consumer's propensity for data processing, and the types of advertising have no significant interaction effect on consumer's preference.

Research on Sensibility Image of Pattern Applying the Formative Elements of a Traditional Jokakbo -The Surface Composition and Colors- (조각보의 조형성을 응용한 패턴의 감성 이미지 연구 -면 구성과 색채를 중심으로-)

  • Eun Young-Ja;Choi Yoon-Hye
    • The Research Journal of the Costume Culture
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    • v.13 no.2 s.55
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    • pp.289-299
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    • 2005
  • Through the formative analysis of the traditional jokakbo, we have composed surface composition that was made by a perfect square, triangle, a weather vane type, vertical type, cintamani type, and a mixed rectangular. And we have composed 18 kinds of motif stimulants that was made by vivid tone, pale tone, and so on, and finally analyzed sensibility image, preference rate of them. The cause of composition for the sensibility image of stimulant was composed by the cause of simplicity characteristics, interesting characteristics, rigid-flexibility characteristics, and modern characteristics. And from these things, the cause of simplicity characteristics and the cause of interesting characteristics were revealed as important dimensional factors of sensibility image. The sensibility image of motif was revealed as a simple image of perfect square, a feminine image of cintamani type, a modern image of mixed rectangular. And black-white colored mixed rectangular and chromatic colored cintamani type were also revealed as an interesting image. The preference rate of motif is related with the cause of interesting characteristics and simplicity characteristics, it also has been revealed to prefer the pale tone than others. And it also has been revealed that achromatic colored mixed rectangular, cintamani type of vivid tone, perfect square and rectangular of pale tone were mostly preferred.

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