• Computers and Concrete
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• v.12 no.4
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• pp.499-518
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• 2013

Fiber reinforced polymer (FRP) jackets have been widely used as an effective tool for the strengthening and rehabilitation of concrete structures, especially damaged concrete columns. Therefore, a clear understanding of the compressive behavior of FRP-confined concrete is essential. The objective of this paper is to develop a simple efficient method for predicting the compressive strength, the axial strain at the peak stress, and the stress-strain relationship of FRP-confined concrete. In this method, a compressive strength model is established based on Jefferson's failure surface. With the proposed strength model, the strength of FRP-confined concrete can be estimated more precisely. The axial strain at the peak stress is then evaluated using a damage-based formula. Finally, a modified stress-strain relationship is derived based on Lam and Teng's model. The validity of the proposed compressive strength and strain models and the modified stress-strain relationship is verified with a wide range of experimental results collected from the research literature and obtained from the self-conducted test. It can be concluded that, as a competitive alternative, the proposed method can be used to predict the compressive behavior of FRP-confined concrete with reasonable accuracy.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1057-1059
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• 1999

Recently, increased demand of electrical energy caused additional installation of underground power cable, Industrialization of metro makes civil works difficult. So installed ducts became a key of underground power transmission, LG cable set to work development of high stress cable. LG cable stated in 1996, got a certificate of type test in 1998, and applied at domestic site in Nov. 1999. High stress cable has some merit, decrease of civil cost, reduction of work time, by reason of decrease of dia. and weight, and economical system design, so LG cable has a good merit in comparison with competitive company in domestic and foreign market.

• The Journal of Industrial Distribution & Business
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• v.7 no.1
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• pp.19-25
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• 2016

Purpose - The purpose of this paper is to aim to stress the importance of doing business environment in South Korean economy. The theoretical justification is based on neo-institutional theories and new business management including Porter's Model as main justifications of state intervention due to the market failures to promote a competitive environment of doing business. Research design, data and methodology - The methods to be taken is to provide a comparative performance analysis, and offer in terms of doing business and economic freedom sub-index complemented by Korean reforms diagnostics. Results - The main results underlined the key factors explain the success of business environment in South Korea such as: a simplified registration procedures, a target tax incentives, the removal of business barriers, the improvement of legislative and regulatory framework, target reforms, property right and technical norms, good governance and the quality of institution, a role of a well-functioning legal framework, a strong competition framework, and the transparency of regulation, etc. Conclusion - A competitive environment of doing business is based on the target national strategies, appropriate reforms responding to national needs and good governance system.

• Structural Engineering and Mechanics
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• v.53 no.5
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• pp.867-880
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• 2015

Mechanical fastening is still one of the main methods used for joining components. Different techniques have been applied to reduce the effect of stress concentration of notches like fastener holes. In this work we evaluate the feasibility of combining laser shock peening (LSP) and cold expansion to improve fatigue crack initiation and propagation of open hole specimens made of 6061-T6 aluminum alloy. LSP is a new and competitive technique for strengthening metals, and like cold expansion, induces a compressive residual stress field that improves fatigue, wear and corrosion resistance. For LSP treatment, a Q-switched Nd:YAG laser with infrared radiation was used. Residual stress distribution as a function of depth was determined by the contour method. Compact tension specimens with a hole at the notch tip were subjected to LSP process and cold expansion and then tested under cyclic loading with R=0.1 generating fatigue cracks on the hole surface. Fatigue crack initiation and growth is analyzed and associated with the residual stress distribution generated by both treatments. It is observed that both methods are complementary; cold expansion increases fatigue crack initiation life, while LSP reduces fatigue crack growth rate.

• Journal of the Korean Home Economics Association
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• v.35 no.2
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• pp.33-47
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• 1997

The purpose of the study is to examine the differences between rural and urban in the factors and the level of stress in adolescent, inner control and communication with parents. Also, It is to research the influence of environmental variables, inner control and communication with parents on adolescent's stress in sides of rural and urban. Therefore, I provide needed data in instructing students. For the data set, academic high school students in second grade in a town for rural and Su-Seung gu, Dal-Sugu, chung gu in Dae-gu for urban were chosen. The data were analyzed with the frequency, percentage, factor analysis Mean, S.D, reliability, t-test, regression in use of Spss PC+ Program. The main results are as follow. First, for rural students, stress level is displayed studies, future0affair, life-attitude, companions, self-assurance and home life in order by lower sphere. For urban students, it is displayed future-affair, studies, life-attitude, companions, self-assurance and home life in order by lower shpere. In case of rural "I don't know effective study method" is highly displayed by factors. In case of urban. "I am tired of a competitive life" is highly displayed. The mean of stress level is 3.22 for rural and 3.07 for urban. The differences between rural and urban are showed in self-assurance, studies and companions. Finally when we see the stress generally the stress level is higher in rural high school students than in urban high school students. Second, rural students are lower displayed than urban students in inner control and communication with parents. There is no difference urban students in inner control and communication with parents. There is no difference in communication with a mother. third, influential variables on stress level are inner control, communication with parents, satisfaction with companions and school life as environmental variables in sides of rural and urban. Physical condition is added for rural and sex for urban Finally we get the result that stress level is high in low inner control, poor communication with parents, bad companions and unsatisfied school life for both rural and urban. Bad physical condition for rural and female for urban are added.

• CELLMED
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• v.1 no.1
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• pp.4.1-4.4
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• 2011

Excessive stress is harmful to academic performance in children and may lead to dropping out of school. To meet the demands of a modern life-style which is full of speed, stress and tension, an all-round child health program is crucial. The use of yoga for children has diverse applications in maintaining and developing their physical, mental, intellectual, emotional and spiritual levels. Yoga, through its physical postures (asana), breathing practices (pranayama), cleansing techniques (kriya), meditation therapies (dhyana) and relaxation training (yoga nidra) yields a positive effect in the management of stress in children. Yoga practice benefited children by improving their eye-hand coordination, attention span, levels of concentration, competitive performance and relaxation. Visually impaired children showed a significant decrease in their abnormal anxiety levels when they practiced yoga for three weeks, while a program of physical activity had no such effect. Socially disadvantaged children in a remand home showed significant improvements in sleep, appetite and general well being, as well as a decrease in physiological arousal after yoga. In one study, it is found that a 4-week program of asana and meditation lowers the aggressive behavior of children. Meditation helped to reduce problems related to maladaptive behavior, increase emotional and physical health and psychological well-being in children. Finally, the possible role of yoga in improving the mental state and general well-being of children with cancer is being explored.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.448-451
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• 2007

DuPont Teijin $Films^{TM}$ (DTF) have developed engineered substrates specifically for the flexible electronics market. $Teonex^{(R)}$ Q65, $Melinex^{(R)}$ ST506 and ST504 are biaxially oriented crystalline polyesters with the option of planarised surfaces. These films are emerging as competitive materials for the base substrate in OLED displays and active matrix backplanes. Given the demanding dimensional reproducibility requirements in the display applications, it is critical to control the several factors that can influence the film distortion in order to achieve the ultimate performance. This paper will discuss the impact of thermal stress, mechanical stress and the processing environment on dimensional reproducibility of polyester film and give examples of how this impacts on the film in device manufacture.

• The Journal of Industrial Distribution & Business
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• v.13 no.6
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• pp.19-36
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• 2022

Purpose: The purpose of this study is to analyze the effects of COVID 19. The effects of COVID 19 are grouped into 5; economic stress, mental stress, health stress, task concern, self-confidence. We introduce the concept of personal ambidexterity that is necessary power for cabin crews to provide appropriate and efficient service to passengers. Ambidexterity consists of exploiting existing resources to sustain and exploring the new including method of performing task, customer, market etc. The former is necessary to maintain present condition while the latter is necessary to prepare for the future. Also motive is considered as a stimulating factor for task. Previous studies show that motive affects ambidexterity and we try to analyze whether COVID 19 effects influence this relationship. Research design, data, and methodology: Considering the relationship between the variables, we designed to measure the influence of the effects of COVID 19 by analyzing the moderating effects of them. For empirical analysis we distributed survey questionnaire and collected. Total of 361 samples are used fo the analysis. For analysis program, SPSS version 23 was used. Regression analysis and moderating effect analysis were conducted. Results: Study results show that first, the variables of economic stress, mental stress, health stress, task concern, self confidence affects personal ambidexterity and service provision. Also ambidexterity affects service provision significantly. Among COVID 19 effects, economic stress, task concern, and self confidence has moderating effects. On the other hand, new work environment does not have moderating effect. Conclusions: In conclusion, the effects of COVID 19 are wide and various. Among them the most serious effect is that COVID 19 is depriving workers of self confidence and passion toward the work. To remedy stresses and restore self confidence and passion, each worker should make his/her own efforts, such as, learning more to become more competitive, also firms should do make efforts to protect employees and to rebuild trust between firm and employees in every respect. Especially firms should realize that economic stress can be treated by economic compensation as the situation turns to normal but trust as well as self confidence and passion is not easy to restore.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.247-252
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• 2010

The present study has been performed to select the osmotic tolerant lines using polyethylene glycol (PEG 6000) through an in vitro and in vivo mutagensis with a gamma-ray. During the screening, we selected three mutant lines that seemed to confer elevated osmotic tolerance in high concentrations of PEG 6000. Fruits of these mutants (Os-HK101, Os-HK102 and Os-HK103) were increased to sugar concentration, L-glutamine acid, vitamin C content and lycopine content than those of the wild type. Also the chlorophyll contents were few decreased more in the three mutant lines than the WT plants. Our results suggest that the Os-HK101 is characterized as osmotic stress tolerance considering the sugar concentration and lycopine content. It is expected that the result of this study can be used for breeding more competitive species with respect to contents in sugar or functional chemicals from the selected osmotic resistant lines.

• Journal of Oriental Neuropsychiatry
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• v.33 no.1
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• pp.33-48
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• 2022

Objectives: Academic stress poses a significant risk for the mental health of medical students, and a feasible group intervention program for managing academic stress is required. The purpose of this study was to examine the clinical effectiveness of emotional freedom techniques (EFT) on the mental health of Korean medical students. Methods: The class of first-year medical school students (n=36) participated in an after-school EFT group intervention program comprising six sessions (15 minutes/session, three weeks) to analyze its clinical effectiveness as a single-group test-retest clinical study. The changes in the Perceived Stress Scale (PSS), Test Anxiety Inventory (TAI), Positive and Negative Affect Schedule (PANAS), and State-Trait Anxiety Inventory (STAI) scores were examined using a paired t-test and Cohen's D at post-EFT and two-week follow-up. Results: There were significant curtailments at post-EFT and follow-up measures in TAI-Total (t=2.704 and t=3.289), TAI-Worry (t=2.297 and t=2.454), TAI-Emotionality (t=2.763 and t=3.654), PSS-Negative Perspective (t=2.659 and t=3.877), and PANAS-Negative Affect (t=2.885 and t=3.259) subscales, however not in PSS-Positive Perspective (t=-1.279 and t=-1.101) and PANAS-Positive Affect (t=0.194 and t=-0.122) subscales. The trait anxiety (t=2.227) was significantly mitigated in the post-EFT measure and the state anxiety (t=2.30) in the follow-up measure. Conclusions: The EFT group intervention alleviated test stress, negative affect, and anxiety in the Korean medical students. This study contributes to an understanding of academic stress and EFT intervention in the competitive environment of medical education.