• Title/Summary/Keyword: stres

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Analysis of Stress by Electromagnetic Force in a Small HTS Single Pancake Coil (소형 고온초전도 싱글 팬케이크 코일의 전자기력에 의한 Stress 해석)

  • Park, Myung-Jin;Kwak, Sang-Yeop;Lee, Seoung-Wook;Kim, Woo-Seok;Hahn, Seoung-Young;Choi, Kyeong-Dal;Han, Jin-Ho;Lee, Ji-Kwang;Jung, Hyun-Kyo;Seong, Ki-Chul;Hahn, Song-Yop
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.869-870
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    • 2006
  • 일반적으로 초전도선재를 이용한 코일의 전자기력에 의한 스트레스 계산에 있어서는 코일의 전류밀도분포와 자속밀도분포의 선형적인 관계를 이용하나 아직까지 초전도체 특유의 비선형적인 특성을 이용한 스트레스의 계산은 미비하다. 본 논문에서는 13턴의 소형 싱글팬케이크 코일을 초전도의 특성을 적용해 해석하고 인가전류가 $0.3I_c,\;0.5I_c,\;0.8I_c$ 인 경우에 대해서 전자기력에 의한 코일의 스트레스를 유한요소법으로 계산하였다. 계산 결과 코일의 radial stress와 hoop stress는 모두 코일의 자속밀도분포와 유사한 모습을 나타내었다.

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Study on residual stress characteristics according to the substrate type and V/III ratio during GaN growth by HVPE (HVPE 법을 통한 GaN 성장 시 기판 종류 및 V/III 비에 따른 잔류 stress 특성 연구)

  • Lee, Joo Hyung;Lee, Seung Hoon;Lee, Hee Ae;Kang, Hyo Sang;Oh, Nuri;Yi, Sung Chul;Lee, Seong Kuk;Park, Jae Hwa
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.30 no.2
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    • pp.41-46
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    • 2020
  • The characteristics of the residual stress on the types of the substrate was investigated with adjusting the V/III ratio during GaN growth via the HVPE method. GaN single crystal layers were grown on a sapphire substrate and a GaN template under the conditions of V/III ratio 5, 10, and 15, respectively. During GaN growth, multiple hexagonal pits in GaN single crystal were differently revealed in accordance with growth condition and substrate type, and their distribution and depth were measured via optical microscopy(OM) and white light interferometry(WLI). As a result, it was confirmed that the distribution area and depth of hexagonal pit tended to increase as the V/III ratio increased. Moreover, it was found that the residual stress in GaN single crystal decreased as the distribution area and depth of the pit increased through measuring micro Raman spectrophotometer. In the case of GaN growth according to substrate type, the GaN on GaN template showed lower residual stress than the GaN grown on sapphire substrate.

A Study on the Secondary Optimization Analysis based on the Result of Primary Structure Analysis for the Die Thickness (금형두께에 대한 1차 구조해석 결과를 기반으로 한 2차 최적화 해석에 관한 연구)

  • Lee, Jong-Bae;Kim, Sang-Hyun;Woo, Chang-Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.6
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    • pp.3448-3454
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    • 2014
  • Generally existing structure analysis was applied to elastic analysis basically in practice. Considering the nonlinear material and the nonlinear geometric to be a more precise analysis, for this reason, The necessity for a structual analysis have been constantly required. Therefore, after optimization is performed, designed a simple model which is applied the principle of nonlinear in this study, a structural analysis of existing experienced users, have a aims at presenting theory and a method in order to perform anyone the analysis easily. In this study, the proposed model applied to die ribs, Regarding the shear load, less strain and stress was generated but strength was sufficient. The initial strain and stress was reconfigured to fit the size and shape, A hyperstudy in conjunction with Abaqus with nonlinear structural analysis, revealed an acceptable maximum and minimum range of stress and under the conditions of minimum strain, the plate made with a constant increment. In the experimental models, the plate thickness was given a power of 40 Newton, according to the thickness of the press die through an iterative process. When the stress and strain was applied to the die thickness, 7-8mm thickness could be obtained by optimizing.

Psychosocial Stress Levels and Related Factors in some Rural Residents (일부 농촌지역 주민에서 사회심리적 스트레스 수준과 관련요인)

  • Han, Mi-Ah;Kim, Ki-Soon;Park, Jong;Ryu, So-Yeon;Kang, Myung-Geun
    • Journal of agricultural medicine and community health
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    • v.33 no.1
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    • pp.46-58
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    • 2008
  • Objectives: This study was performed to investigate the levels of psychosocial stres and to identify its Methods: The study subjects were 1,806 adults aged 40-70 years living in Naju City, Jeollanamdo. Sociodemographic characteristics, health-related behavior, social suport and personality were collected for statistical analysis. The measurement instrument of psychosocial stress was psychosocial well-being index. The regression analysis. Results: The results showed that 16.6% of subjects were categorized as high stress, 63.4% as moderate, and 20.0% as normal. Overall, the mean value of PWI was 17.29.8 and significantly diferent by socioeconomic characteristics, health-related behavior, social suport and personality. In the case of men, the income, decreased positive social suport, increased negative social suport, type A behavior pattern, decrease of internal locus of control or poorer self-esteem. In the case of women, the PWI was significantly deteriorated in the subjects with no job, no spouse, decreased positive social suport, increased negative social support, type A behavior pattern, decrease of internal locus of control or poorer self-esteem.Conclusions: The psychosocial stres for rural residents was related with social suport and personality. Thus, these results should be considered to reduce stres levels in rural adults.

Proteomic Analysis of Protein Changes in Human Lung Cancer Epithelial Cells Following Streptococcus pneumoniae Infection (Streptococcus pneumonia 감염으로 변화한 사람 폐 상피세포 단백질의 프로테오믹 분석)

  • Lee, Yun Yeong;Chung, Kyung Tae
    • Journal of Life Science
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    • v.23 no.8
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    • pp.1050-1056
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    • 2013
  • Streptococcus pneumoniae is the leading cause of community-acquired pneumonia throughout the world. The bacteria invade through lung tissue and cause sepsis, shock, and serious sequelae, including rheumatic fever and acute glomerulonephritis. However, the molecular mechanism associated with pneumonia's penetration of lung tissue and invasion of the blood stream are still unclear. We attempted to investigate the host cell response at protein levels to S. pneumoniae D39 invasion using human lung cancer epithelial cells, A549. Streptococcus pneumoniae D39 began to change the morphology of A549 cells to become round with filopodia at 2 hours post-infection. A549 cell proteins obtained at each infection time point were separated by SDS-PAGE and analyzed using MALDI-TOF. We identified several endoplasmic reticulum (ER) resident proteins such as Grp94 and Grp78 and mitochondrial proteins such as ATP synthase and Hsp60 that increased after S. pneumoniae D39 infection. Cytosolic Hsc70 and Hsp90 were, however, identified to decrease. These proteins were also confirmed by Western blot analysis. The identified ER resident proteins were known to be induced during ER stress signaling. These/ data, therefore, suggest that S. pneumoniae D39 infection may induce ER stress.

A Study on Electromagnetic Force of Interior Permanent Magnet Motor (매입형 영구자석 동기전동기 전자기력 특성 연구)

  • Lee, Seung-Ho;Jung, Sang-Yong
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1061-1062
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    • 2011
  • 본 논문에서는 매입형 영구자석 동기전동기(IPMSM) 전자기력 특성 해석을 수행하였다. 전동기에서 발생하는 전자기력(Electromagnetic force)은 기기의 성능 뿐만 아니라 소음 및 진동을 유발하며 전기기기의 stress를 야기한다. 본 논문에서는 전자기력 특성을 맥스웰 응력 텐서법를 이용하여 각 노드에서 발생하는 전자기력 분포에 대해 분석하였다. 그리고 매입형 영구자석 전동기의 운전상태 및 구조파트 중 고정자 치에서 발생하는 전자기력 분포에 대해 분석하였다.

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A New Resonant Type Inverter with Low Voltage Stress (낮은 전압 Stress를 갖는 새로운 공진형 인버터)

  • Jung, Yong-Chae;Cho, Gyu-Hyeong
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.1150-1153
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    • 1992
  • A new soft-switching resonant type inverter is proposed to obtain the low voltage stress. In this proposed inverter, only one additional switch is used for the soft commutation. Therefore, a simple structure and a easy control can be available. Moreover, the PWM capability can be highly improved due to tile convenient choice of switching condition. Based on the operational principle, analysis and design procedures are described. Through the simulation, the operation of the proposed invertor is verified.

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A measure of goodness of fit for network representations (네트워크 표현을 위한 합치도 지표)

  • Lee, Jae Yun
    • Proceedings of the Korean Society for Information Management Conference
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    • 2012.08a
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    • pp.133-136
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    • 2012
  • 지적구조의 시각적인 표현을 위해서 오랫동안 다차원척도법이 사용되어 왔으나, 최근에는 패스파인더 네트워크와 같이 네트워크의 형태로 표현하는 방법이 확산되고 있다. 다차원척도법에 대해서는 생성된 2차원 지도의 품질을 평가하기 위한 합치도 지표로 STRESS나 RSQ를 비롯한 여러 종류가 사용되고 있는 반면, 네트워크 표현에 대해서는 마땅한 합치도 지표가 아직까지 제안되지 않았다. 이 글에서는 개체 간의 연관성을 네트워크로 표현할 경우에, 생성된 네트워크 구조를 평가하기 위한 합치도 지표로 NetRSQ를 제안하였다.

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Bond Stress-Slip Model for Serviceability Verification on Structural Concrete Members (철근콘크리트 부재의 사용성능 검증을 위한 부착응력-미끄럼 모델)

  • Lee, Gi-Yeol;Yang, Jun-Ho;Chung, Won-Yong;Rho, Sam-Young;Kim, Dae-Joong;Kim, Woo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.17-18
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    • 2009
  • This research defined slip function using cracking behavior, bond characteristics and numerical analysis of cracking stabilized reinforced concrete member, and proposed a bond stres-slip model.

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