• Title/Summary/Keyword: AE pattern

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Degradation Diagnosis of Complex System Using Regression Analysis (희귀분석을 이용한 복합 시스템의 열화진단)

  • Kim, Seong-Hong;Song, Jae-Joo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.09a
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    • pp.60-66
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    • 2001
  • Because of internal voids in insulators give rise to partial discharge(PD), which cause local breakdown and even entire insulation breakdown. Treeing due to PD is one of the main causes of breakdown of the insulating materials and reduction of the insulation life. Therefore the necessity for establishing a method to diagnose the aging of insulation materials and to predict the breakdown of insulation has become important. From this viewpoint, our studies diagnose insulation degradation using the method of computer sensing system, which has the advantages of PD and acoustic emission(AE) sensing system. To use advantages of these two methods can be used effectively to search for treeing location and PD in some materials. In analysis method of degradation, We analyzed the PD pulse and AE pulses by regression analysis, compared to these obtained the correlation coefficient and determination coefficient by T-distribution and saw that PD and AE pulses show a similar pattern on the whole. This is in agreement with the results of the research by Yoshimura and Fujita.

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A Life Prediction of Insulation Degradation Using Complex Sensing System (복합 감지 시스템을 이용한 부분방전의 절연열화 수명추정)

  • Kim, S.H.;Kim, J.H.;Park, J.J.;Choi, J.K.;Yoon, H.J.;Lee, Y.S.
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.348-350
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    • 1997
  • Because of internal voids ininsulators give rise to partial discharge(PD), which cause local breakdown and even entire insulation breakdown. Treeing due to PD is one of the main causes of breakdown of the insulating materials and reduction of the insulation life. Therefore the necessity for establishing a method to diagnose the aging of insulation materials and to predict the breakdown of insulation has become important. From this viewpoint, our studies diagnose insulation degradation using the method of computer sensing system, which has the advantages of PD and acoustic emission(AE) sensing system. To use advantages of these two methods can be used effectively to search for treeing location and PD in some materials. In analysis method of degradation. We analyzed the PD pulse and AE pulses by regression analysis, compared to these obtained the correlation coefficient and determination coefficient by T-distribution and saw that PD and AE pulses show a similar pattern on the whole. Finally using statically operator such as the center of gravity(G), the gradient of the discharge distribution(C), we have analyzed for the prediction of life which we can be obtained the time, occurred of many pulse of small discharge amplitude.

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Degradation Diagnosis of Complex System Using Regression Analysis (회귀분석을 이용한 복합 시스템의 열화진단)

  • 김성홍;박재준;김재환
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.13 no.1
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    • pp.39-45
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    • 1999
  • Because of internal voids in insulators give rise to partial discharge(PD), which cause local breakdown and even entire insulation breakdown. Treeing due to PD is one of the main causes of breakdown of the insulating materials and nrluction of the insulation life. 1berefore the necessity for establishing a rrethod to diagnose the aging of insulation materials and to predict the breakdown of insulation has becorne irrportant. From this viewpoint, our studies diagnose insulation degradation using the rrethod of computer sensing system, which has PD and acoustic emission(AE) sensing system. To use advantages of these two methods can be used effectiveiy to search for treeing location and PD in sorre materials. In analysis rrethod of degradation, we analyzed the PD and AE pulses by regression analysis, corrpared to these obtained the correlation coefficient and retermination coefficient by T-distribution and saw that PD and AE pulses show a similar pattern on the whole. This has a similar teIlrency to the results of the research by Yoshimura and Fujita.Fujita.

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Investigation of Fracture Propagation in Cement by Hydraulic Fracturing Under the Tri-axial Stress Condition (시멘트 시료에 대한 삼축압축 환경에서의 수압파쇄시험 연구)

  • Riu, Hee-Sung;Jang, Hyun-Sic;Jang, Bo-An
    • The Journal of Engineering Geology
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    • v.27 no.3
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    • pp.233-244
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    • 2017
  • We conducted hydraulic fracturing experiments on cement samples to investigate the dependency of fracture propagation on the viscosity of injection fluid and the in situ stress state. Ten cubic samples (20 cm side length) were produced using cement that was cured in water for more than one month. Samples were placed in a tri-axial compression apparatus with three independent principal stresses. An injection hole was drilled and the sample was hydraulically fractured under a constant injection rate. We measured injection pressures and acoustic emissions (AE) during the experiments, and investigated the fracture patterns produced by hydraulic fracturing. Breakdown pressures increased exponentially with increasing viscosity of the injection fluid. Fracture patterns were dependent on differential stress (i.e., the difference between the major and minor principal stresses). At low differential stress, multiple fractures oriented sub-parallel to the major principal stress axis propagated from the injection hole, and in some samples the fracture orientation changed during propagation. However, at high differential stress, a single fracture propagated parallel to the major principal stress axis. AE results show similar patterns. At low differential stress, AE source locations were more widespread than at high differential stress, consistent with the fracture pattern results. Our study suggests that hydraulic fracturing during shale gas extraction should be performed parallel to the orientation of minimum differential stress.

A Study of Blood Stasis Pattern for Frozen Shoulder Using Blood Stasis Pattern Questionnaires (BSPQ) and the Relationship of Pain, Shoulder Range of Motion and BSPQ Score (어혈변증 설문지를 통한 오십견의 어혈변증 평가 및 통증, 견관절 운동범위와 어혈변증과의 관계)

  • Kwon, Sin-Ae;Lee, Jung-Woo;Kim, Min-Jung;Song, Ji-Yeon;Sung, Won-Seok;Seo, Byung-Kwan;Woo, Hyun-Su;Baek, Yong-Hyeon;Park, Dong-Suk
    • Journal of Acupuncture Research
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    • v.28 no.4
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    • pp.49-55
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    • 2011
  • Objectives : The purpose of this study was 1) to investigate the possibility of taking blood stasis pattern as a clinical parameter of frozen shoulder, using blood stasis pattern questionnaire (BSPQ) to frozen shoulder group comparing with normal group, and 2) to find out the relationship of the severity of main frozen shoulder symptoms (pain and limited range of motion of shoulder) and the level of blood stasis pattern through BSPQ analysis. Methods : During the period of January 2010 to July 2010, fifty five frozen shoulder patients who visited outpatient clinic of department of acupuncture and moxibustion in East-West Neo Medical Center, Kyung Hee University and fifty five normal people without shoulder pain nor limited ROM in shoulder joint were evaluated through BSPQ, and to the frozen shoulder group, also evaluated three different visual analogue scales (VAS) of pain (pain on average, pain at night, and pain on motion) and active / passive range of motion (ROM) of shoulder joint. Results : Mean blood stasis pattern score of frozen shoulder patients group was significantly higher than the score of normal group (patients vs normal group : $4.85{\pm}1.68$ vs $3.49{\pm}1.54$). Three different types of pain VAS (on average, at night and on motion) showed low to very low positive correlation with BSPQ scores when analyzed with Pearson's correlation coefficient. ROM levels in shoulder joint were not significantly related to BSPQ scores, though active external rotation range showed low positive correlation with BSPQ scores. Conclusions : Patients with frozen shoulder showed higher blood stasis pattern score in BSPQ but the level of blood stasis pattern is not significantly related to the severity of pain or limitation of ROM in shoulder joint.

Development of Slacks Pattern for Old Aged Abdominal Obese Women (복부 비만 노년 여성을 위한 슬랙스 패턴 개발)

  • Kim, Seon-Ok;Kweon, Soo-Ae;Yoo, Jung-Ja
    • Korean Journal of Human Ecology
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    • v.18 no.1
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    • pp.157-166
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    • 2009
  • This study was conducted to evaluate the differences in external appearances and functional qualities between the slacks which were patterned on existing designs and on a new design in order to improve on their level of comfort of ready-made clothes for abdominally fat women. Five abdominally fat women in their 60's were chosen as experimental participants. Twenty-four external evaluation items, and seven different actions involving six moving parts of the body were investigated with a 5-level scale in the repeated wearing test. The results were analyzed by statistical methods. The newly designed pattern in this study was definitely superior to the other two patterns(L-type and K-type) on the external appearance evaluation. The newly pattern removed a waist belt and a dart from the front part of the garment and gave surplus space around the waist. It prevented superfluous wrinkles at the abdominal region and thighs. The superfluous wrinkles at the side regions also disappeared due to the length (inseam) reduction from waist to crotch. The newly pattern made the center-line of the back side slightly sloped to the main pattern in order to remove the drooped line. The newly pattern showed the highest score in the functional test of several actions. It was due to the reduction of the length from waist to crotch as well as the belt width. It made waist-line movement better, and made it easier and more comfortable to sit down. The newly pattern also showed the highest score in the functional test classified by specific movements of parts of the body for the same purpose. The slacks which were made of elastic materials showed better results than the non-elastic ones on external appearances and functional test items. It showed that the elastic materials played a better role in the increase of functional action of abdominally fat, aged women. This study suggests that the newly designed slacks pattern could give abdominally fat, aged women better external features and a more comfortable fitting sensation. As well, the results were significant as basic data to produce ready-made and/or tailer-made garments.

Technical Design of Tight Upper Sportswear based on 3D Scanning Technology and Stretch Property of Knitted Fabric (3차원 스캔 기술과 니트 소재의 신축성을 적용한 밀착형 스포츠웨어 상의 설계)

  • Kim, Tae-Gyou;Park, Soon-Jee;Park, Jung-Whan;Suh, Chu-Yeon;Choi, Sin-Ae
    • Fashion & Textile Research Journal
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    • v.14 no.2
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    • pp.277-285
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    • 2012
  • This research studied how to develop tight upper sportswear from 3D scan data considering fabric stretch property. Subjects were five Korean men of average figure in their 20's. Scanning was done for ten postures via vitus smart/pro(Techmath LTD). Analyzing from 3D scan data, more than 70% of the upper body surface showed surface change rate under 20%. It was shoulder and under arm side part that showed most noticeable body surface change when moving. A parametric model with convex surface was generated and flattened onto the plane, resulting 2D pattern. The error rate occurring in the process of 3D to 2D conversion was 0.2% for outline and 0.13% for area, respectively. Thirteen kinds of stretchable fabrics in the market were collected for this study. Stretch property was in the range of 16.0~58.2% for wale direction; 23.1~78.4% for course. Based on wear trial test, four fabrics were chosen for making the 1st experimental garment and finally one fabric was chosen for the 2nd one, which was developed applying 4 kinds of crosswise reduction rate on 2D pattern: 0, 5, 10, and 15%. Through wear trial test and garment pressure measurement, experimental garment applied with 10% pattern reduction rate was evaluated as most comfortable and considerable.

Mobile Web Automatic Generation using the Web users usage pattern (사용자 이용패턴을 이용한 모바일웹 컨텐츠 자동 생성에 관한 연구)

  • Ko, Hee-Ae;Kim, Jong-Keun;Sim, Kun-Ho;Meihua, Zhao;Yin, Chang-Yi;Lim, Young-Hwan
    • Journal of Digital Contents Society
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    • v.9 no.4
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    • pp.583-590
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    • 2008
  • These days Mobile web Full Browsing is getting the issues which displays whole Web Site contents in browser of mobile device. Since the size of browser is too small, in this paper, it recommends a new method that web users can choose variable service and web contents for mobile contents by adopting new platform. The mobile web would be generated automatically to apply the web 2.0 through the web users pattern. The platform is that no one belong in data, anyone can use this, anyone can modify the data, so variable users can create new contents for proper mobile web. It is the Mobilder application which can build Mobile web pages. Any User can make mobile web pages with Mobilder Before producing the program, in this paper, it will build mobile web pages by web users navigation pattern. After analysing the web users pattern, we will produce the mobile web pages through this.

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Textile Design using Contents of Jeju Myth, Jacheongbi (제주신화 자청비(청비) 콘텐츠를 응용한 텍스타일 디자인)

  • Oh, Jeong-Soon;Na, Hyun-Shin;Jang, Ae-Ran
    • Journal of the Korean Society of Costume
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    • v.62 no.7
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    • pp.170-184
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    • 2012
  • The purpose of this study is, as one of Jeju culture contents projects, to suggest a new method to develop the textile design using contents of Jeju Myth, Jacheongbi, in other words, to create mythic patterns by borrowing effectively from the mythic image of Jacheongbi on contemporary fashion. To achieve this, after extracting mythic contents from real animals from the myth (chicken, horse, cow and owl) of Jacheongbi, we draw the animal motifs from a mythic image basis of archetypal symbols and empirical awareness about animals and shamanistic imagination, and create mythic patterns. In order to achieve this design pattern, Adobe Photoshop CS5 Extended was used to design the animal motifs, and then they were arranged via bidirectional layout. And to conclude, development of the creative textile design using the mythic contents of Jacheongbi contribute to invigorating the fashion industry and regional culture contents projects in Jeju, and also become the basis of creating added value to it.

Relationship between the oral Health, oral health impact profile-14 and total health index of male workers (남성 근로자들의 구강건강, 구강건강영향지수 및 전신건강 지수의 관련성)

  • Kang, Hyun-Kyung;Jang, Kyeung-Ae
    • Journal of Korean society of Dental Hygiene
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    • v.13 no.1
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    • pp.13-20
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    • 2013
  • Objectives : This research is performed to arrange oral health improvement program and improve the quality of life by raising total health index of male workers. The relationship between the oral health, oral health index and total health index of workers are investigated through the direct or indirect effects based on structural equational modeling. Methods : Total 272 people who work in Gyeong-Nam province participated in this survey. Results : Oral health knowledge has an meaningful direct effects on the oral health practice with ${\gamma}$=.259 and dietary pattern with ${\gamma}$=.224. Total health index has indirect relationship with the oral health index with ${\beta}$=.141 and dietary pattern has direct relationship with the oral health index with ${\beta}$=.315. The oral health index has direct relationship with total health index with ${\beta}$=.454. Conclusions : Our research shows that there is meaningful relationship between the oral health, oral health index and total health index of workers. The systematic and continuous programs for oral health should be transferred to workers for the raise of oral health and the quality of the life.