• Title/Summary/Keyword: stress resistance

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The Effects of Character Pattern on Stress Resistance -of Elderly People- (성격유형이 스트레스 저항에 미치는 영향 -노인 대상-)

  • Youn, Il-Shim;Yi, Seon-Gyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.11
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    • pp.4819-4825
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    • 2011
  • This study tried to find out whether character patterns of elderly people are related to stress resistance using brain waves, personal physiological index of cranial nerves. The data were gathered by 1,108 seniors(age 65 and over) who were requested to check brain waves from September, 2007 to December, 2010 in Korean Institute for Research of Psychiatry. 552 of the subject showed the propensity to positive behavior, 556 of them showed the propensity to negative behavior. 735 of the subject showed the propensity to cheerful emotion, 373 of them showed the propensity to depressed emotion. As a result the propensity of emotion was significantly related to the stress resistance, but not the propensity of behavior. In other words, the propensity to cheerful emotion showed higher average stress resistance index than the propensity to depressed emotion. So the person who has the propensity to cheerful emotion can cope with stress better. This study shows the propensity to emotion is related to stress resistance. The influence of the propensity to emotion and how it works should to be studied.

Investigation of One-dimensional Stress-Release Mechanism in Sand from Model Test

  • Zhuang, Li;Kim, Dongwook;Kim, Ukgie
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.10
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    • pp.17-27
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    • 2013
  • This paper explores stress release induced by unloading in dry sand. A series of model tests were carried out to measure stresses developed in testing sand during loading and those released during unloading for different boundary conditions. It was found that stress in the sand increased linearly with applied load. At the onset of unloading, almost no stress release was observed. Significant stress release took place when the shear stress in the sand induced by unloading exceeded the frictional resistance and caused movement of sand particles. The initiation and the magnitude of stress release depend on the stress condition prior to unloading, the decrease of external load, and also the frictional resistance in sand. A new conceptual stress-release model was next developed based on the model test results by considering the fundamental frictional behavior of granular materials.

Survival Factor Gene FgSvf1 Is Required for Normal Growth and Stress Resistance in Fusarium graminearum

  • Li, Taiying;Jung, Boknam;Park, Sook-Young;Lee, Jungkwan
    • The Plant Pathology Journal
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    • v.35 no.5
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    • pp.393-405
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    • 2019
  • Survival factor 1 (Svf1) is a protein involved in cell survival pathways. In Saccharomyces cerevisiae, Svf1 is required for the diauxic growth shift and survival under stress conditions. In this study, we characterized the role of FgSvf1, the Svf1 homolog in the homothallic ascomycete fungus Fusarium graminearum. In the FgSvf1 deletion mutant, conidial germination was delayed, vegetative growth was reduced, and pathogenicity was completely abolished. Although the FgSvf1 deletion mutant produced perithecia, the normal maturation of ascospore was dismissed in deletion mutant. The FgSvf1 deletion mutant also showed reduced resistance to osmotic, fungicide, and cold stress and reduced sensitivity to oxidative stress when compared to the wild-type strain. In addition, we showed that FgSvf1 affects glycolysis, which results in the abnormal vegetative growth in the FgSvf1 deletion mutant. Further, intracellular reactive oxygen species (ROS) accumulated in the FgSvf1 deletion mutant, and this accumulated ROS might be related to the reduced sensitivity to oxidative stress and the reduced resistance to cold stress and fungicide stress. Overall, understanding the role of FgSvf1 in F. graminearum provides a new target to control F. graminearum infections in fields.

Computation of Crack Tip Mode I Stress Intensity Factor of a Specimen for Measuring Slow Crack Growth Resistance of Plastic Pipes Using Finite-Element Method (유한요소법에 의한 플라스틱 파이프의 저속균열성장 저항성 시험편 균열선단 모드 I 응력확대계수 계산)

  • Choi, Sun-Woong;Park, Yeong-Joo;Suh, Yeong-Sung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.9 s.240
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    • pp.1225-1234
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    • 2005
  • Mode I stress intensity factor $(K_I)$ of Notched Ring Test(NRT) specimen for measuring slow crack growth resistance was found using finite-element method. The theoretical $K_I$ value of NRT was not available in any references and could not be solved analytically. At first, in order to verify the accuracy of the finite-element approach, published $K_I$ values of several cracks were calculated and compared with finite-element results. The results were in good agreement within inherent errors of theoretical $K_I$. Finally the mode I stress intensity factor of NRT was found using 2- and 3-dimensional finite-element methods and expressed as a function of the applied load. This enabled direct comparison of resistance to slow crack growth between NRT and Notched Pipe Test(NPT), which employ different loading regime.

Normalization of Cone Resistance in Granular Soil (모래지반에서 콘 저항값의 정규화에 관한 연구)

  • Na Yung-Mook
    • Journal of the Korean Geotechnical Society
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    • v.20 no.9
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    • pp.33-45
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    • 2004
  • Sandfill at reclaimed sites is usually formed by more than one placement method. Reclaimed sandfill often shows highly variable profiles and the cone penetration test is most commonly used for site characterization. Correlations between cone resistance and geotechnical parameters for sand are influenced by in-situ stress level and it is important to incorporate stress level effect. In this study, cone penetration tests were performed at several elevations from the top of a 10m high surcharge, which was later removed step by step. In order to establish more reliable correlations between cone resistance and geotechnical parameters for sand, different ways of normalizing cone resistance by the corresponding in-situ vertical stress were investigated.

Evaluation of Impact Resistance of Hybrid Fiber Reinforced Cementitious Composites Subjected to Thermal Stress (열응력을 받은 하이브리드 섬유보강 시멘트 복합체의 내충격성능 평가)

  • Han, Seung-Hyeon;Kim, Gyu-Yong;Lee, Yae-Chan;Eu, Ha-Min;Park, Jun-Young;Nam, Jung-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.05a
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    • pp.145-146
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    • 2023
  • In this study, the effect of hybrid fiber reinforcement on the residual strength and impact resistance of high-strength cementitious composites exposed to high temperatures was investigated. A cementitious composites was manufactured in which 0.15 vol% of polypropylene fiber (PP) and 1.0 vol% of smooth steel fiber (SSF) were double-mixed, and a residual strength test was conducted while thermal stress was applied by heating test, and then a high-velocity impact test was performed. In the case of general cementitious composites, the rear surface is damaged due to explosion and low tensile strength during high temperature or impact, while hybrid fiber reinforced cementitious composites can repeatedly absorb and distribute stress until multiple fibers are damaged to suppress the propagation of impact and resistance to explosion. Therefore, this study analyzed the residual strength of cementitious composites exposed to high temperatures depending on whether hybrid fibers were mixed or not, and collected research data on fracture behavior through high-speed impact tests to evaluate impact resistance and mechanical properties.

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A Study on the Relations between Yangseng Level and Stress in Industrial Workers (근로자(勤勞者)의 양생수준(養生水準)과 스트레스와의 관계(關係))

  • Ahn, Hun-Mo;Kim, Sung-Sam;Kim, Wan-Gyeom;Yu, Ho-Dal;Chong, Myong-Soo;Lee, Ki-Nam
    • Journal of Society of Preventive Korean Medicine
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    • v.11 no.1
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    • pp.109-129
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    • 2007
  • This study aims at grasping the relativity between laborers' yangseng level and stress so as to present the groundwork for preventive oriental medicine approach in industrial health. The researcher prepared the questionnaire on general character, health-related yangseng level and chose 632 people to execute Autonomic balance test through heartbeat change. The collected material was analyzed by SPSS and tested by T-test, ANOVA. The general yangseng level average is 3.27, morality yangseng 3.91, sleep yangseng 3.39, mind yangseng 3.32, sex life yangseng 3.29, exercise yangseng 3.14, activities and rest yangseng 3.07, diet yangseng 2.95, seasonal yangseng 2.84. The highest is morality yangseng and seasonal yangseng is the lowest. In the aspect of yangseng level : Having a spouse, Non-smoking, Non-drinking, Regular exercising, Sufficient sleeping have higher yanseng levels. In Autonomic balance test, age from 35 to 40 has the highest autonomic activity and job period from 5 years to 10 years has the highest stress resistance. Non-smokers have high autonomic activity and stress resistance. Further, have low autonomic balance, stress index and fatigue strength. In the case of regular exercising person, he/she has high autonomic activity and stress resistance with low stress index. Regarding sleeping time, autonomic balance is the highest when he/she sleeps less than 6 hours. Stress resistance is the highest when he/she sleeps 7 hours and stress index is the highest when he/she sleeps 6 hours. After comparing the relativity between yangseng level autonomic balance test, only exercise yangseng has plus factor on autonomic activity and stress resistance and minus factor on stress ind ex and fatigue strength. Yangseng level has been affected by individual character and daily habits. Also stress is more influenced by daily habits than by individual character. We can find the relativity of exercise yangseng between yangseng and stress which suggests that we need to take measures to win over stress in individual health in the near future.

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Enhanced bacterial resistance in transgenic tobacco expressing a BrRZFP1 encoding a C3HC4-type RING zinc finger protein from Brassica rapa

  • Jung, Yu Jin;Nou, Ill Sup;Hong, Sung Kee;Lee, Young Kee;Cho, Yong Gu;Kang, Kwon Kyoo
    • Journal of Plant Biotechnology
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    • v.40 no.1
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    • pp.49-54
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    • 2013
  • C3HC4-type RING zinc finger proteins essential in the regulation of plant processes, including responses to abiotic stresses. We previously isolated and examined the C3HC4-type RING zinc finger protein (BrRZFP1) from Brassica rapa under abiotic stresses. To elucidate the role of the BrRZFP1 transcription factor in gene regulation, we transformed tobacco plants with the BrRZFP1 gene. Plants were regenerated from 82 independently transformed callus lines of tobacco and analysed for transgene expression. Transgene integration and expression was confirmed by Southern and RT-PCR analyses, respectively. T2 plants displayed more tolerance to the bacterial pathogens Pectobacterium carotovorum and Ralstonia solanacearum, and the tolerance levels were correlated with BrRZFP1 expression levels. These results suggest that the transcription factor BrRZFP1 is an important determinant of stress response in plants and its overexpression in plants could increase biotic stress resistance.

A Study on the Relations between Yangseng Level and Stress in Industrial Workers (근로자(勤勞者)의 양생수준(養生水準)과 스트레스와의 관계(關係))

  • Ahn, Hun Mo;Kim, Sung Sam;Kim, Wan Gyeom;Yu, Ho Dal;Chong, Myong Soo;Lee, Ki Nam
    • Journal of Korean Medical Ki-Gong Academy
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    • v.10 no.1
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    • pp.100-129
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    • 2007
  • This study aims at grasping the relativity between laborers' yangseng level and stress so as to present the groundwork for preventive oriental medicine approach in industrial health. The researcher prepared the questionnaire on general character, - health-related yangseng level and chose 632 people to execute Autonomic balance test through heartbeat change. The collected material was analyzed by SPSS and tested by T-test, ANOVA The general yangseng level average is 3.27, morality yangseng 3.91, sleep yangseng 3.39, mind yangseng 3.32, sex life yangseng 3.29, exercise yangseng 3.14, activities and rest yangseng 3.07, diet yangseng 2.95, seasonal yangseng 2.84. The highest is morality yangseng and seasonal yangseng is the lowest. In the aspect of yangseng level: Having a spouse, Non-smoking, Non-drinking, Regular exercising, Sufficient sleeping have higher yangseng levels. In Autonomic balance test, age from 35 to 40 has the highest autonomic activity and job period from 5 years to 10 years has the highest stress resistance. Non-smokers have high autonomic activity and stress resistance. Further, have low autonomic balance, stress index and fatigue strength. In the case of regular exercising person, he/she has high autonomic activity and stress resistance with low stress index. Regarding sleeping time, autonomic balance is the highest when he/she sleeps less than 6 hours. Stress resistance is the highest when he/she sleeps 7 hours and stress index is the highest when he/she sleeps 6 hours. After comparing the relativity between yangseng level autonomic balance test, only exercise yangseng has plus factor on autonomic activity and stress resistance and minus factor on stress index and fatigue strength. Yangseng level has been affected by individual character and daily habits. Also stress is more influenced by daily habits than by individual character. We can find the relativity of exercise yangseng between yangseng and stress which suggests that we need to take measures to win over stresses in individual health in the near future.

Effects of Shot Peening on Crack Growth Resistance in Carburized Gears (침탄치차의 쇼트피닝처리가 크랙진전억제에 미치는 영향)

  • 류성기;정인성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.12
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    • pp.3227-3235
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    • 1994
  • This paper deals with an evaluation of the residual stress due to shot peening induced in a carburized gear tooth and its application to the fatigue crack propagation problem. A practical method is proposed on the basis of the assumption that the residual stress is caused by the difference of volume expansion in the case and the core, and the influence of both the reduction of retained austenite and the strain due to shot peening are considered. The evaluated residual stress is close to the measured stress, though the surface stress is rather overestimated. The stress intensity factor is computed by the influence function method, and it is shown that the factor is decreased by the residual stress in shot peened gear tooth. The shot peening is fairly effective to the reduction of fatigue crack growth rate. The crack propagation is simulated and the resistance due to shot peening is quantitatively demonstrated and discussed.