• Title/Summary/Keyword: Stress view

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Effect of Sintering Time on Surge Stress Characteristics of ZPCCY-Based Varistors (ZPCCY계 바리스터의 써지 스트레스 특성에 소결시간의 영향)

  • Park, Jong-Ah;Kim, Myung-Jun;Yoo, Dae-Hoon;Nahm, Choon-Woo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.408-411
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    • 2004
  • The electrical stability against surge stress of ZPCCY-based varistors were investigated at different sintering times. Sintering time decreased the varistor voltage and nonlinear exponent from 279.6 to 179.1 and from 52.5 to 24.9, respectively. On the contrary, the leakage current and dielectric dissipation factor increased from 1.2 to 9.8 ${\mu}A$ and from 0.0461 to 0.0651 with increase of sintering time. For all varistors, the variation rates of V-I characteristic parameters against surge stress were affected in order of varistor voltage$\rightarrow$nonlnear exponent$\rightarrow$leakage current. On the whole, the electrical stability against surge stress increased with increasing sintering time. Conclusively, it is assumed that the varistor sintered for 2 h exhibited comparatively good characteristics, in view of overall characteristics.

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Stress Analysis on the Cam-Roller Contact Parts in a Marine Diesel Engine (박용 디젤기관 캠-롤러 접촉부의 응력 해석)

  • 김형자;임우조;조용주;구영필
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.2
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    • pp.174-180
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    • 2002
  • The subsurface stress field beneath the roller's contacting surface due to the contact pressure in lubricating condition has been calculated. Main purpose of this study in view of engineering is to prove the validity of the numerical profile roller presented by Koo et al. The Love's rectangular patch solution was used to obtain the subsurface stress field. The stress field of the numerical profile roller was compared with the one of the existing dub-off profile roller The analysis results show reduced subsurface stresses for the numerical profile roller.

Are Magnetic Resonance Imaging Findings of Ankle Instability Always Correlated with Operative and Physical Examination Findings? (외측 인대 손상의 자기공명영상 소견들이 수술 소견 및 신체검사와 항상 일치할까?)

  • Park, Hyun-woo
    • Journal of Korean Foot and Ankle Society
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    • v.25 no.1
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    • pp.1-5
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    • 2021
  • Physical examination and surgical findings and symptoms are often inconsistent with magnetic resonance imaging (MRI) findings when diagnosing chronic ankle lateral ligament instability, and confirmed surgical findings are used as the gold standard in most clinical studies. Anterior drawer testing is considered unreliable because normal findings are highly variable, and its accuracy ranges from 50% to 100%. Furthermore, radiographic stress imaging, such as in anterior drawer stress view, is performed under manual stress or using a stress device, and its findings also vary widely and confuse when interpreting stress views. The average accuracy of MRI findings is around 85% (range, 66%~91.7%), and thus, cannot be used as a primary indicator for surgery. For patients with suspected lateral ankle ligament instability, based on symptoms and physical examination findings, MRI may be useful for identifying lesions in ankle joints and for differentiating them from other conditions.

Improvement of K+ and Na+ Ion homeostasis and salt tolerance by Co-inoculation of arbuscular mycorrhizal fungi (AMF) and spore associated bacteria (SAB)

  • Selvakumar, Gopal;Kim, Kiyoon;Roy, C. Aritra;Jeon, Sunyong;Sa, Tongmin
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.246-246
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    • 2017
  • Salinity inhibits plant growth and restricts the efficiency of arbuscular mycorrhizal fungi. The selective uptake of nutrients from the soil and their effective transport to host roots make it essential for plant growth and development under salt stress. AMF spore associated bacteria shown to improve mycorrhizal efficiency under stress. Thus, this study aimed to understand the co-inoculation efficiency of AMF and SAB on maize growth and ion homeostasis under salt stress. Two AMF strains and one SAB were inoculated with maize either alone or in combination with one another. The results of our study showed that AMF and SAB co-inoculation significantly improved dry weight and nutrient uptake of maize under salt stress. Co-inoculation significantly reduced proline accumulation in shoots and Na+ accumulation in roots. Co-inoculation treatment also exhibited the high K+/Na+ ratios in roots at 25 mM NaCl. Mycorrhizal colonization showed positive influence for regulation of ZmAKT2, ZmSOS1 and ZmSKOR gene expressions, contributing to K+ and Na+ ion homeostasis. CLSM view showed that SAB were able move and localize into inter and intra cellular spaces of maize roots. In addition, CLSM view of AMF spores showed that gfp-tagged SAB also associated on the spore outer hyaline layer.

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Analysis of Steel/composite Cylinder by GUI Program (GUI를 이용한 특수강/복합재 이중구조 후육실린더 해석)

  • Kim, Chi-Wan;Kim, Wie-Dae
    • Composites Research
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    • v.25 no.4
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    • pp.126-132
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    • 2012
  • It is useful to have a quick analysis program in early design process for feasibility studies of composite cylinder because it takes long time and is not cost effective by commercial programs. In this paper, a GUI program is developed to calculate the stress distribution in a fast manner with the properties, the orientation angle and the stacking sequence of composite material using LabVIEW. The stress distributions of an autofrettaged cylinder and a composite cylinder with internal pressure are compared with the results by MSC Nastran/patran. The stress distribution of steel/composite cylinder is compared with the values of existing studies, and is proved. Furthermore, by calculating the stress distribution of an autofrettaged steel/composite cylinder, the stress distribution is estimated, and the program will be useful in an early design phase for feasibility studies.

The Results of Modified $Brostr{\ddot{o}}m$ Procedure for the Treatment of Chronic Lateral Ankle Instability (만성 족근 관절 외측 불안정성 환자에서 $Brostr{\ddot{o}}m$ 변형 술식의 치료 결과)

  • Jeon, Ho-Seung;Jeon, Seung-Ju;Kim, Jong-Min;Park, Byeong-Mun;Chang, Byung-Keun
    • Journal of Korean Foot and Ankle Society
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    • v.10 no.1
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    • pp.60-65
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    • 2006
  • Purpose: This study was performed to evaluate clinical and radiographical results of treatment of chronic lateral ankle instability with modified Brostrom procedure. Materials and Methods: This is a retrospective study of 22 cases in 22 patients treated with modified $Brostr{\ddot{o}}m$ procedure under the diagnosis of chronic lateral ankle instability from May 2000 to August 2004. Average age was 32.3 years. Average follow-up period was 23 months. Preoperative and postoperative radiographs of ankle anteroposterior view, lateral view and varus stress view were analyzed. The clinical evaluation was performed according to the Americal Orthopaedic Foot and Ankle Society scales. Results: After the modified $Brostr{\ddot{o}}m$ procedure, Americal Orthopaedic Foot and Ankle Society scales score was improved by average 28 points. Among the 22 cases, 13 cases were excellent, 3 cases good, 4 cases fair, and 2 cases poor with satisfaction of 73%. Five cases had intermittent ankle pain of whom 3 cases had difficulty during competitive sports activity. Lateral tilting of talus improved by average 5.4 degrees on varus stress view. Conclusions: The modified $Brostr{\ddot{o}}m$ procedure is one of the most effective methods for treating of chronic lateral ankle instability.

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Modified Micro-Mechanical Fiber Bridging Model for Crack Plane of Fiber Rreinforced Cementitious Composite (섬유보강 복합체의 균열면 해석을 위한 수정 미세역학 모델)

  • Shin, Kyung-Joon;Park, Jong-Bum
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.365-368
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    • 2006
  • In this paper, the post cracking stress-crack width relationship of the composite is studied from a micromechanics points of view. Cook-Gordon debonding effect is studied by more refined method with considering of chemical friction of fiber interface. As a result, fiber with pre-debonding length retards stress development and shows more wide crack width for the same force level. longer pre-debonding length and lower pre-debonding bond strength results in lower full-debonding force, but same crack width.

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Impact of Financial Instability on Economic Activity: Evidence from ASEAN Developing Countries

  • TRAN, Tra Thi Van
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.1
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    • pp.177-187
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    • 2022
  • Theoretical literature agrees on the interaction between financial instability and economic activity but explains it's dynamic in two points of view: one is that the transmission mechanism occurs in one unique regime and the other reckons a shift of regime leads to the alteration of the transmission mechanism. This study aims to find evidence of the multi-regime transmission for ASEAN developing countries. The author employs the technique of Threshold vector auto regression using the financial stress index standing for financial instability. Monthly data is collected, covering a period long enough with many episodes of high stress in recent decades. There are two conclusions: (1) A financial shock has a negative and stronger impact on economic activity during a high-stress period than it does during a low-stress period; (2) the response of economic activity to a negative financial shock during high-stress periods is stronger than it is during normal times. The findings point to the importance of the financial stress index as an additional early warning indicator for the real economy sector, as well as the positive effect that a reduction in financial stress may have on economic activity, implying the importance of "unconventional" monetary policy in times of high financial stress.

The Effect of Job Stress of Beauty Industry Employees on Turnover Intention

  • Eun-Jung SHIN
    • The Journal of Industrial Distribution & Business
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    • v.15 no.3
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    • pp.31-46
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    • 2024
  • Purpose: Employees in the beauty industry, where emotional labor is essential, are exhausted due to stress from excessive working hours and low pay, and ultimately consider changing jobs. This study analyzed the structural relationship of turnover intention according to job stress of beauty industry employees. We tried to present implications by verifying the methods necessary for conflict management in the beauty industry from an empirical point of view. Research design, data and methodology: This study selected 518 workers in the beauty industry as a sample. Frequency analysis, validity and reliability analysis, factor analysis, correlation analysis, and regression analysis were performed using SPSS (Statistical Package for Social Science) WIN23.0. Results: The moderating effect of work experience, a moderating variable, was found to be significant in the effect of job stress of beauty industry employees following changes in the employment environment on the dependent variable, turnover intention. Conclusion: This study revealed that changes in the employment environment negatively affect the job stress of beauty workers. To reduce the job stress of employees in the beauty industry, a systematic response at the organizational level will be necessary. In addition, it is expected that it will help establish differentiated strategies such as compensation system, service training, and service management to reduce job stress.

Turbulence Characteristics in a Circular Open Channel by PIV Measurements

  • Kim, Sun-Gu;Sung, Jae-Yong;Lee, Myeong-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.7
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    • pp.930-937
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    • 2011
  • The characteristics of mean velocity and turbulence have been analyzed in the circular open channel flow using PIV measurement data for a wide range of water depth. The measured data are fitted to a velocity distribution function over the whole depth of the open channel. Reynolds shear stress and mean velocity in wall unit are compared with the analytic models for fully-developed turbulent boundary layer. Both the mean velocity and Reynolds shear stress have different distributions from the two-dimensional boundary layer flow when the water depth increases over 50% since the influence of the side wall penetrates more deeply into the free surface. The cross-stream Reynolds normal stress also has considerably different distribution in view of its peak value and decreasing rate in the outer region whether the water depth is higher than 50% or not.