• Title/Summary/Keyword: Variable stress

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The Effects of Mental Health on Obesity among Korean Adolescents (한국 청소년의 정신건강이 비만에 미치는 영향)

  • Kim, Kwan-Ok;Jeon, Yun-Hee;Kim, Yoon-Shin
    • Journal of Digital Convergence
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    • v.12 no.10
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    • pp.467-476
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    • 2014
  • This study aims to determine the effects of mental health on obesity among Korean adolescents. The data in this study were obtained from the 2013 Korean Youth Health Risk Behavior Web-based Survey conducted in 70,354 adolescents aged twelve to eighteen (35,575 males and 34,779 females) from June 1 to 30, 2013. The variables included age, the economic status of household, academic achievement, health status, perceived happiness, perceived stress, satisfaction of sleeping, perceived depression, and suicidal ideation and the data were processed using t-test, chi square test, and logistic regression analysis. The general characteristics affecting obesity for both Korean male and female adolescents included age (p<0.001), the economic status of households (p<0.001), academic achievement (p<0.001), and health status (p<0.001); the variable of mental health affecting obesity was suicidal ideation among females (p<0.05). It is expected that female adolescents' experience of suicidal ideation can be used as information to predict the likelihood of obesity in managing an obesity program for adolescents and it is necessary to provide obesity education suitable for age and to include obesity guidance in consideration of gender and the economic status.

Ginseng Transformation of Betaine Aldehyde Dehydrogenase Gene Relative Salt Resistant through Somatic Embryogenesis (염류내성관련 유전자 Betaine Aldehyde Dehydrogenase Gene의 인삼 체세포 배발생을 통한 형질전환)

  • Yoon Young-Sang;Bae Chang-Hyu;Song Won-Seob;Yoon Jae-Ho;Yang Deok-Chun
    • Korean Journal of Plant Resources
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    • v.18 no.1
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    • pp.15-21
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    • 2005
  • Korean ginseng(Panax ginseng C.A. Meyer) is very difficult to obtain stable production of qualified ginseng roots because of variable stresses in soil environments. In transformation of ginseng with betain aldehyde dehydrogenase gene, compounds synthesized for controlling osmotic pressure such as proline, glycine, betaine, polyols and sugar were accumulated in cell for salt resistance in transgenic plants. 2 Agrobactgerium conjugants were acquired with bet A and bet B genes for solt resistant plants. A. tumefaciens MP90/pBetA and A. tumefaciens MP90/pBetB were recombined for increasing the tolerance to salt stress. To confirm the transformation of the binary vector, tobacco plant was transformed, and the transformant can grow on media containing high concentration of kanamycin. To identify NPT 11, BetA and BetB genes of the transformants, the band on the agarose was confirmed by PCR and RT-PCR techniques. The transformants of ginseng with bet A and bet B genes were acquired on the phytohormone free basic MS media containing only antibiotics and 1M mannitol used for selection of transgenic plant, but the transfomation efficiency for BetA and BetB was very low.

Probabilistic Service Life Analysis of GGBFS Concrete Exposed to Carbonation Cold Joint and Loading Conditions (탄산화에 노출된 GGBFS 콘크리트의 콜드 조인트 및 하중 재하를 고려한 확률론적 내구수명 해석)

  • Kim, Tae-Hoon;Kwon, Seung-Jun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.24 no.3
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    • pp.39-46
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    • 2020
  • Carbonation is a deterioration which degrades structural and material performance by permitting CO2 and corrosion of embedded steel. Service life evaluation through deterministic method is conventional, however the researches with probabilistic approach on service life considering loading and cold joint effect on carbonation have been performed very limitedly. In this study, probabilistic service life evaluation was carried out through MCS (Monte Carlo Simulation) which adopted random variables such as cover depth, CO2 diffusion coefficient, exterior CO2 concentration, and internal carbonatable materials. Probabilistic service life was derived by changing mean value and COV (Coefficient of variation) from 100 % to 300 % and 0.1 ~ 0.2, respectively. From the analysis, maximum reduction ratio (47.7%) and minimum reduction ratio (11.4%) of service life were obtained in cover depth and diffusion coefficient, respectively. In the loading conditions of 30~60% for compressive and tensile stress, GGBFS concrete was effective to reduce cold joint effect on carbonation. In the tensile condition, service life decreased linearly regardless of material types. Additionally service life rapidly decreased due to micro crack propagation in the all cases when 60% loading was considered in compressive condition.

An Experimental Study of Flexible-Stiff Mixed System of High Yield Ratio-High Strength Steel for the Practical Use (고항복비-고강도강의 유강혼합구조 시스템 적용에 관한 실험적 연구)

  • Oh, Sang Hoon;Kim, Jin Won;Moon, Tae Sup
    • Journal of Korean Society of Steel Construction
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    • v.17 no.4 s.77
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    • pp.395-405
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    • 2005
  • This paper summarizes the test results of the flexible-stiff mixed system for the effective use of high-strength steel. Steel with a high degree of strength and performance is being increasingly required as buildings get larger and taller. High-strength steels cannot be used for many applications, though, because they have a number of defects. For instance, they have a high yield ratio, a small strain in maximum stress, and equal Young's modulus compared to mild steels. A new structural system is needed to effectively use high-strength steels with some defects. This paper proposes the flexible-stiff mixed system for the effective use of high-strength steels with high yield ratios. The possibility of using the system is discussed through the test of flexible-stiff mixed columns with high-strength steels. The main variable of the specimens is the yield displacement ratio, including both the force ratio and the stiffness ratio. The proper yield displacement ratio is proposed by adopting the flexible-stiff mixed system. The test results showed that the proposed flexible-stiff mixed system has a high capacity for energy absorption and the highest capacity for energy absorption when the yield displacement ratio of the flexible element to the stiff element ranges from 2.7 to 3.3.

Convergence Study on Damage and Static Fracture Characteristic of the Bonded CFRP structure with Laminate angle (적층 각도를 가진 CFRP 접착 구조물의 파손 및 정적 파괴 특성에 관한 융합 연구)

  • Lee, Jung-Ho;Kim, Eundo;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.10 no.1
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    • pp.155-161
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    • 2019
  • As composite is the light weight material whose durability and mechanical property are more superior than the existing general material. By taking notice of the composite with light weight, this study was about to investigate the static fracture characteristic of the bonded CFRP structure jointed with adhesive. Also, CFRP double cantilever beam with the variable of laminate angle was designed and the static fracture analysis was carried out. The laminate angles of CFRP double cantilever beam designed for this study were $30^{\circ}$, $45^{\circ}$ and $60^{\circ}$ individually. As the study result, the specimen with the laminate angle of $45^{\circ}$ was shown to have the durability better than those with the layer angles of $30^{\circ}$ and $45^{\circ}$. It was checked that the specimen with the laminate angle of $30^{\circ}$ had the weakest durability among all specimens. The damage data of the bonded CFRP structure by laminate angle could be secured through this study result. As the damage data of bonded interface obtained on the basis of this study result are utilized, the esthetic sense can be shown by being grafted onto the machine or structure at real life.

Convergence Study on Damage of the Bonded Part at TDCB Structure with the Laminate Angle Manufactured with CFRP (CFRP로 제작된 적층각도를 가진 TDCB 구조물에서의 접착부의 파손에 관한 융합 연구)

  • Lee, Dong-Hoon;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.9 no.12
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    • pp.175-180
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    • 2018
  • In this study, CFRP was manufactured with the laminate angle of $45^{\circ}$. The specimen of TDCB bonded with the adhesive for structure was designed by CATIA and the analysis was progressed by using the finite element analysis program of ANSYS. This study model was designed on the basis of British industry and ISO standard and the configuration factor(m) was established with variable according to the angle of model configuration. As the study result of this paper, the maximum deformations at the specimens with the tapered angles of $4^{\circ}$ and $8^{\circ}$ become most as 12.628 mm and least as 12.352mm respectively. Also, the maximum equivalent stresses at the specimens with the tapered angles of $6^{\circ}$ and $8^{\circ}$ become most as 9210.3 MPa and least as 4800.5 MPa respectively. The damage data of TDCB structure with the laminate angle which was manufactured with CFRP could be secured through this study result. As the damage data of TDCB structure bonded with CFRP obtained on the basis of this study result are utilized, the esthetic sense can be shown by being grafted onto the machine or structure at real life.

A Study on the Noise and Vibration Damping Performance of RC Hollow Core Slab (중공형 RC 슬래브의 소음 및 진동 감쇠성능에 대한 연구)

  • Kim, Dong Baek;Kim, In Bae;Kim, Jong Hoon;Lee, Jae Won
    • Journal of the Society of Disaster Information
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    • v.15 no.2
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    • pp.292-300
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    • 2019
  • Purpose: To reduce the noise and vibration of reinforced concrete slab structures, the damping performance is to be performed experimentally after installing hollow core or filling it with liquid. Method: Using the hollow rate as an experimental variable, the damping ratio and stiffness of each test specimen at impact load are obtained to determine the difference between the damping ratio and stiffness of the numerical analysis. In addition, the damping effects are reviewed by comparing the difference in the damping ratio and stiffness of a test specimen filled with liquid 50% of the study. Results: Since the difference in resistance between a specimen with or without hollow core is 5%, it is judged that there is no structural problem, and the injection of liquid into the hollow core can increase the damping ratio, which can reduce noise or vibration. Conclusion: At less than 20% of hollow rate, there was little damping effect, and at 30%, damping effect was found. However, if liquid is injected into the hollow core of the specimen, damping rate is shown to increase, and the injection of liquid into the hollow part is believed to reduce noise or vibration.

The Impact of Medical Utilization on Subjective Health and Happiness Index and Quality of Life according to the Economic Level of the Elderly (노인의 경제적 수준에 따른 의료이용이 주관적 건강수준과 행복감 지수 및 삶의 질에 미치는 영향)

  • So, Kwon-Seob;Hwang, Hye-Jeong;Kim, Eun-Mi
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.3
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    • pp.544-552
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    • 2019
  • The purpose of this study was to find concrete measures to improve the subjective health level, happiness and quality of life of the elderly according to economic level and to propose social and policy alternatives accordingly. As a research method, 63,929 elderly people aged 65 or older were surveyed using the Community Health Survey (Indicator Bank) _v09, and the frequency of health use by economic level, subjective health level, euphoria and quality of life Analysis and Chi square analysis and independent t-test. Multi variate logistic regression analysis was performed with subjective health level as a dependent variable and multiple linear regression analysis was performed to determine the factors affecting euphoria and quality of life. The results of the study are as follows. In the case of recipients, medical use was lower than that of non-recipients, lower education level, female age of 75 years or older, and less stress, In case of present or past recipients, the result of non - receipt increased as the subjective health level was worse, and the non - recipient had higher euphoria and quality of life. As a result, there is a need for alternatives to increase opportunities for medical use among the recipients, with particular attention being paid to women and elderly people over 75 years old. It is expected to be used as a basic data to effectively improve the health promotion, happiness and quality of life of the elderly people of low income group.

Factors Influencing Psychological Well-being of Nursing Students (간호대학생의 심리적 안녕감에 영향을 미치는 요인)

  • Park, Jin-Ah;Hong, Ji-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.4
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    • pp.448-457
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    • 2019
  • This descriptive study was conducted to identify the factors affecting the psychological well-being of nursing students. A questionnaire survey was conducted on 298 nursing college students attending two universities in G city from April 10 to May 9, 2018. The research tools were used 27 items of Professor Trust Scale, 25 items of emotional regulation, 25 items of Connor-Davison Resilience Scale, and 18 items of psychological well-being scale. psychological well-being was significant different according to gender(p=.019), grade(p=.011), motivation of choosing a nursing(p=.003), major satisfaction(p<.001), stress of clinical practice(p=.002), and current health status(p<.001). There were significant positive correlations between psychological well-being and professor trust, active emotion regulation, support-seeking emotion regulation, and ego-resilience and negative correlation between psychological well-being and avoidant-distractive emotion regulation. The results of multiple regression analysis are as follows. Factors influencing the psychological well-being of nursing students were ego-resilience, support-seeking emotion regulation, avoidant-distractive emotion regulation, major satisfaction and these variables explained the psychological well-being by 55.0%(F=30.92, p<.001). It is necessary to develop a curriculum/comparative programs and student coaching plans for improving ego-resilience which is the most influential variable. Also internal or environmental and social support should be strengthened so that negative emotions caused by various causes can be efficiently managed.

The Effects of Compassion and Virtue experienced by police officer on Organizational Identification : Mediating effects of positive emotions and moderating effect of collective self-esteem (경찰관들이 경험하는 컴페션(Compassion)과 미덕(Virtue)이 조직 동일시에 미치는 영향: 긍정적 감정의 매개효과와 집단적 자긍심의 조절효과)

  • Jo, Seung-Won
    • Journal of Digital Convergence
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    • v.17 no.5
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    • pp.1-10
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    • 2019
  • The purpose of this study is to verify the effect of the compaction and virtue experienced by police officers in the organization on positive emotion and, second, to demonstrate the effect of positive emotion on the organization uniformity, which is subordinate variable. Third, we intend to verify the mediated effect of positive emotion in the relationship between compassion and organization uniformity, and fourthly, to demonstrate the coordination effect of collective self-esteem in the relationship between positive emotion and organization identicalness. Sampling of this study was conducted on 353 male and female police officers working at police stations belonging to the National Police Agency and used these samples for hypothesis testing. Studies have confirmed that the compaction and virtue experienced by police officers have a positive effect on positive emotion, and that positive emotion has a positive effect on the phenomenon of tissue co-ordination. And it has been shown that positive emotion plays a full role in the relationship between compassion, virtue and organizational co-ordination, and that positive emotion and collective self-esteem plays a controlling role in the relationship with organizational co-ordination. The theoretical implications of this study will contribute to creating a positive organizational culture by maintaining a strict hierarchical relationship and spreading the compaction and virtuous behavior to police organizations with high task stress.