• Proceedings of the Korea Concrete Institute Conference
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• 1990.10a
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• pp.57-62
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• 1990

This paper is to study the effect of rectilinear confinement in high-strength concrete subjected to a monotonically increasing compressive axial loads. To investigate behavior of columns rectilinearly confined with lateral ties and longitudinal rebars, twelve specimens including two plain concrete specimens were tested. The main variables in this study are volumetric ratio of lateral ties, cistribution of lateral ties, yield strength of logitudinal steel, ratio of area of longitudinal steel to the area of cross section. The test results were not only compared with an empirical model for the stress-strain curve of rectilinearly confined high-strength concrete but also the existing model. The empirical model used calculating column capacity shows better agreement with the test results tham the existing model.

• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.171-178
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• 1991

Effects of catecholamines were investigated on isolated strips of the male cattle oesophageal groove. In the circular muscles of the bottom and longitudinal muscles of the lip. isometric tensions was recorded with isometric myograph in 25ml organ bath. The results were as follows: 1. The muscular activity was different in preparations from the two parts. In the longitudinal muscle from the lip, rhythmic contractions generally occurred. while in the circular muscle from the bottom they were not seen almost. 2. In the circular muscle of the bottom, the increased tone and biphasic contractions were caused by catecholamines. And these contractions were mediated through $\alpha$-excitatory adrenoceptor. Also circular muscle showed minor inhibitory response to catecholamines. And these effects were mediated through $\beta$-inhibitory adrenoceptor. But the circular muscle was more sensitive to the $\alpha$-excitatory effect than $\beta$-inhibitory effect. 3. In logitudinal muslce of the lip. rhythmic contractions were reduced or disappeared by catecholamines(especially propranolol) and these effects were mediated through $\beta$-adrenoceptor.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.55-60
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• 2005

In this study, the 1/20 reduced-scale experiments using Froude scaling were conducted to investigate the effect of longitudinal ventilation on the variation of burning rate in tunnel fires. The methanol square pool fires with heat release rate ranging from 3.57 kW to 10.95 kW were used. The burning rate of fuel was obtained by measured mass using load cell and temperature distribution were measured by K-type theomocouples in order to investigate smoke movement. The wind tunnel was connected with one side of the tested tunnel, and logitudinal ventilation velocity in the tested tunnel was controlled by power of the wind tunnel. In methanol fire case, the increase in ventilation velocity decreased the turning rate due to the direct cooling of fire plume. For the same dimensionless velocity(V), homing rate decreased as the size of pool fire increased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.167-174
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• 2021

This study examined the influences of participation in the free semester on school life satisfaction and interest in classes and whether the effect persisted longitudinally. The participants were students from middle schools located in large cities: 451 students in the experimental group and 466 students in the control group. Only the students of the experimental group participated in the free semester. The data were collected at the end of the free semester for three years, and the results are as follows. First, the school life satisfaction of students in the experimental group was significantly higher than those in the control group until the second year but not in the third year. Second, there was no difference in interest in the main subject classes between the experimental and control groups until the third year. Third, students' interest in art and sports classes in the experimental group was significantly higher than those in the control group until the second year but not in the third year. These findings suggest that long-term planning and management of the institution rather than short-term introduction is required for the continuous effects of the free semester.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3007-3015
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• 2012

This study gave an insight into senior life plans and life satisfaction of the middle aged employee over 45 and under 60 years of age, listed in the KLIPS data for 2001 (4th year) and 2008 (11th year), so as to grasp levels of senior life plans of the middle aged employee as well as the longitudinal and short term effects of senior life plans on life satisfaction. The study findings showed as follow: First, For the period of years, the middle aged employees' health got worse and jobs got instable. Second, economic and physical senior life plans of the middle aged employee turned out below an average of three points which means preparations made below the normal level, whereas senior life plans in terms of relation and leisure and social activities came out with more than an average of three points, respectively, which means preparations made above the normal level. Third, as a result of looking into longitudinal effects of the 2001 senior life plans on life satisfaction, the level of senior life plans for leisure and social activities got higher, life satisfaction stayed higher in the year of 2001. In 2008, however, the higher level of economic plans for senior life came out with a higher rate of life satisfaction. From a short-term perspective, therefore, leisure and social activities to enjoy life impose a great impact on life satisfaction, whereas from a long-term viewpoint economic plans for senior life is regarded to be of greater importance.