• Korean Journal of Pharmacognosy
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• v.39 no.4
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• pp.341-346
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• 2008

The effects of the ethanol extracts from Gynostemma pentaphyllum (GP extracts) on body weights, grip strengths, endurances and catecholamine levels after electric footshock (EF) stress in mice and rats were investigated. The animals were treated with GP extracts (50 mg/kg/day, p.o.) for 21 days before exposure to EF (duration and interval 10 sec for 3 min, 2 mA) once a day. The increases in body weights were delayed by 13.1% of the control levels by EF-induced stress in mice, which were recovered to 24.1% of the control levels in GP extract-treated groups. The grip strengths were significantly decreased by EF stress in mice and the EF-stressed groups treated with GP extracts increased grip strengths to 115.2% compared to control levels. The endurance times by forced swimming, which reduced significantly by EF stress, were also maintained similar to control levels by GP extracts in rats. In addition, the levels of norepinephrine and epinephrine in serum and brain, and dopamine in brain were significantly increased to 17.5-95.0% of the control levels after exposure of EF stress in mice. However, EF stressinduced increases in norepinephrine and epinephrine in serum were reduced to 17.1-17.3% of the control levels by treatments of GP extracts, and those in dopamine, norepinephrine and epinephrine in brain were also reduced to 5.0-19.5%. These results suggest that GP extracts showed the protective effects on EF stress-induced physiological functions and can be developed as the promising anti-stress agents.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.480-489
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• 2020

This study was analyzed using Giorgi (1985)'s phenomenological research method to find the essential meaning of the strengths inherent in the experience of national players. The research participants selected the final six athletes who wanted to participate in the national team's individual and team events using the Purposeful sampling method. In-depth interviews were conducted from September to December 2019, and 90 to 180 minutes were conducted once and two in-depth interviews were conducted for each athletes. As a result, categories were derived from 17 sub-factors, 5 factors, and 5 factors were found to make good habits, make my own weapons, think positively, simplify and maintain good condition. The five factors shown in the results are used as strengths when they are voluntarily done, and these strengths create a chance and vitality for players to truly like their sport. These character strengths are expected to be used as positive information for players' development of positive psychology programs and psychological skills training.

• Steel and Composite Structures
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• v.22 no.2
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• pp.429-448
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• 2016

This paper presents a finite element (FE) model for predicting the behaviour of steel column-column connections under axial compression and tension. A robustness approach is utilised for the design of steel column-column connections. The FE models take into account for the effects of initial geometric imperfections, material nonlinearities and geometric nonlinearities. The accuracy of the FE models is examined by comparing the predicted results with independent experimental results. It is demonstrated that the FE models accurately predict the ultimate axial strengths and load-deflection curves for steel column-column connections. A parametric study is carried out to investigate the effects of slenderness ratio, contact surface imperfection, thickness of cover-plates, end-plate thickness and bolt position. The buckling strengths of steel column-column connections with contact surface imperfections are compared with design strengths obtained from Australian Standards AS4100 (1998) and Eurocode 3 (2005). It is found that the column connections with maximum allowable imperfections satisfy the design requirements. Furthermore, the steel column-column connections analysed in this paper can be dismantled and reused safely under typical service loads which are usually less than 40% of ultimate axial strengths. The results indicate that steel column-column connections can be demounted at 50% of the ultimate axial load which is greater than typical service load.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1081-1094
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• 2014

The strut-tie model approach has proven to be effective in the ultimate analysis and design of structural concrete with disturbed regions. For the reliable analysis and safe design of the structural concrete, however, the effective strengths of concrete struts must be determined accurately. In this study, the equations of the effective strengths of concrete struts, which are useful for the three types of determinate and indeterminate strut-tie models of reinforced concrete corbels, were proposed. The effects of shear span-to-effective depth ratio, the vertical-to-horizontal force ratio, and flexural and horizontal shear reinforcement ratios were reflected in the development of the proposed equations. To examine the appropriateness of the proposed and existing equations, the ultimate strengths of 243 reinforced concrete corbels tested to failure were evaluated by using the three types of corbel strut-tie models.

• The Journal of the Acoustical Society of Korea
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• v.34 no.6
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• pp.444-454
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• 2015

Measurements of bottom backscattering strengths in a frequency range of 6-14 kHz were made on the shallow water off the southern Gyeonggi Bay in Yellow Sea in May 2013, as part of the KIOST-HYU joint acoustics experiment. Geological surveys for the experimental area were performed using multi-beam echo sounder, sparker system, and grab sampling to investigate the bottom topography, sub-bottom profile and composition of surficial sediment, respectively. In this paper, the backscattering strengths as a function of grazing angle (in range of $28^{\circ}{\sim}69^{\circ}$) were estimated and compared to the predictions obtained by Lambert's law and APL-UW scattering model. Finally, the effects of geoacoustic parameters corresponding to the experimental area on the backscattering strengths are discussed.

• Journal of the Korea Concrete Institute
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• v.18 no.5 s.95
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• pp.667-675
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• 2006

Concrete is much more easily damaged by various parameters than by the only one and performance reducing mechanism grows more complicated in that condition. In addition, the factors which really act in concrete structure tend to be activated in turn and the degradation of concrete is very rapidly progressed. The purpose of this study is to evaluate the properties of polymer cement mortars under combined cures. The polymer cement mortars are prepared with various polymer types, polymer-cement ratios and cement-fine aggregate ratio, and tested for compressive and flexural strengths, accelerated carbonation, chloride ion penetration and acid resistance test, and freezing-thawing test. The properties of polymer cement mortars under combined cures is discussed. From the test results, polymer cement mortars have superior strengths compared with plain cement mortar under combined cures. The strengths of polymer cement mortars are markedly increased at curing condition II and V, however strengths are not improved at curing condition I and IV irregardless of polymer types. The carbonation and chloride ion penetration depths of polymer cement mortars tend to decrease in curing conditions, III-C, IV-B, V-A order, and decrease with increasing polymer cement ratios. It is concluded that polymer cement ratio of 10 to 15% are considered optimum for the preparation of such polymer cement mortars.

• The Journal of the Korean dental association
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• v.22 no.9 s.184
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• pp.803-811
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• 1984

The purpose of this study was to research how temporary cementation effected on the bond strength of permanent cementation. Zinc phosphate, polycarboxylate and EBA ZOE cements were used as permanent cements, and as temporary cements Nogenol, Tempak and Dycal were used. The ninety six (96) specimens were prepared to measure the bond strength of permanent cements after treated with temporary cements for one week. The tensile stregths were measured with an Instron Universal Test Machine. The results of this study were obtained as follows: 1. With zinc phosphate cement, there was a tendency that the bond strengths of the group of temporarily cemented with Nogenol were increased, meanwhile they were decreased a little in the groups of Dycal and Tempak than those of the control group. 2. With polycarboxylate cement, there was a tendency that the bond strengths of the Control group were higher than those of experimental groups and they were decreased in order of Tempak, Noginol, and Dycal. 3. With EBA ZOE cement, there was a tendency that the bond strengths of the group of temporarily cemented with Tempak were increased a little, meanwhile they were decreased a little in the groups of Nogenol and Dycal than those of the Control group. 4. Among the permanent cements, the bond strengths of polycarbosylate cement were the highest and were followed in order of zinc phosphate cement and EBA ZOE cement.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.337-347
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• 2020

The purpose of this study was to investigate the effects of strengths perspective group art therapy on the strength-related perspectives on the stress, depression and impulsivity of male middle school students who smoke. Data were collected from 15 middle school smokers from two middle schools in A city. Among them, 8 experimental groups and 7 other control groups were willing to participate in art therapy. The collected data were analyzed by nonparametric test considering the number of groups was 15. The Mann-Whitney U test and Wilcoxon signed ranks test were performed. As a result, the strength-focused group art therapy program showed stress (z = -2.521, p <.05), depression (z = -2.527, p <.05), impulse (z = -2.371, p < .05). Therefore, it can be found that strengths perspective group art therapy has a positive effect on the psychological well-being of smoking middle school students, and furthermore, it is necessary to study the deep emotional state of smoking middle school students.

• Journal of Family Resource Management and Policy Review
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• v.23 no.4
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• pp.23-39
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• 2019

This study aimed to explore the moderating effect of family strengths on the effect of work-family conflict on happiness in dual-income married couples. This study included 316 married employees who live in Seoul and have children attending junior high or lower grade schools. A survey was conducted December 1-30, 2018 by distributing questionnaires to child care centers, kindergartens, schools, companies, religious institutions, and other locations. The results are follows. First, in this study, the degree of family→work conflict was higher than that of work→family conflict in dual-income married couples, indicating that role conflict at work is greater due to family role pressures. Second, among the socio-demographic characteristics of dual-career couples, monthly income, family→work conflict (an independent variable), and family problem-solving skills (a moderating variable; a subcategory of family strengths) had a significant impact. In the analysis of the effect of work-family conflict on happiness, the higher the monthly income, the lower the family→work conflict, and the higher the family problem solving ability, the higher the feeling of happiness among dual-income married couples. When the work role conflicts from family life roles were more highly perceived in dual-income married couples. Moreover, family→work conflict and an interaction term of family problem-solving ability were identified as variables that had significant effects on happiness. Third, family problem-solving ability was identified as a moderator buffering the effect of work-family conflict on happiness.

• Physical Therapy Korea
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• v.27 no.4
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• pp.257-263
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• 2020

Background: The hip muscle plays various roles. Several types of functional performance tests are used for the assessment of patients with various lower extremity injuries. Hip muscle functions are important to test the performance of maintaining the spine, pelvic, and leg during bridging exercise. We designed a novel functional performance test tool, which we named close kinetic chain dynamic lower extremity stability (CKCLE) test to assess hip muscle functions. Objects: The purpose of this study was to determine the relationship between CKCLE test and hip extensor, external rotator, and abductor strengths. Methods: Twenty-two subjects were recruited in the present study (13 males and 9 females). The hip extensor, external rotator, and abductor muscle strengths were measured using a Smart KEMA strength sensor. When the examiner said "Go", the subject performed the CKCLE test by moving one leg from the floor and touching the opposite knee and then return to the floor while maintaining the bridging position. The subjects attempted as many "touches" as possible in the allotted time (20 seconds) during the maximal tests. The correlation between the hip muscle (extensor, external rotator, and abductor) strength of the supporting leg and the number of CKCLE tests performed in 20 seconds was determined using the Pearson correlation. Results: Hip extensor (r = 0.626, p < 0.05), hip external rotator (r = 0.616, p < 0.05), and hip abductor muscle strengths (r = 0.475, p < 0.05) positively correlated with the number of CKCLE tests performed. Conclusion: We designed a CKCLE test and found that performance in the test correlated with hip extensor, external rotator, and abductor muscle strengths. The result suggests that the CKCLE test can be applied as a performance test to assess the functions of the hip extensor, external rotator, and hip abductor muscles.