• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.496-499
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• 2006

In this study, a practical method of shrinkage stress analysis on concrete slab in multi-story building is proposed, which considers both internal restraint and external restraint variation resulting from construction sequence. The shrinkage stress due to external restraint is obtained by multiplying relaxation coefficient to elastic shrinkage stress. The additional shrinkage stress due to internal restraint is obtained by residual strain of the elastic analysis. A verification example was analyzed and compared by the proposed method and commercial analysis program that is capable of time-dependent analysis of concrete. The results of 10-story example building show that the internal restraint of reinforcement increases the shrinkage stress considerably at the slabs under loose external restraint.

• Magazine of the Korea Concrete Institute
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• v.8 no.5
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• pp.111-122
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• 1996

The effects of external restraint on the thermal stresses i n mass concrete are investigated through a series of parametric study. Two major factors affecting the degree of external restraint such as the ratio of length to height of the placed structure (L/H) and the elastic modulus of base structure ($E_r$) are employed as the parameters in a condition which a placing height H is 1.0m. Various conditions of I,/H and E, are analysed by a FEM program and the relationship between these two parameters is examined. The shape of stress distribution due to the external restraint is shown as linearity on the height direction of the section, and is influenced by L/H, $E_r$, and strength development of placed concrete. The external restraint can be devided by two part. One is an axial restraint and the other is a flexural restraint. When the level of external restraint is low, the structure behavior is mainly governed by flexural restraint, otherwise it is dependent on axial restraint. Comparing the calculated stress by the method of the ACI 207 committee with a finite element analysis, the fbrmer overestimates the external restraint stress when the degree of external restraint is weak, and underestimates when it is strong.

• Proceedings of the KWS Conference
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• 1995.04a
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• pp.65-67
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• 1995

The solidification crack susceptifility of aluminum alloy weld metal have been evaluated by means of the slef restraint and external restraint cracking test. It has been observed expermently as follows : (1) The manganese is beneficial to decrease the solidification cracking susceptibility. (2) Weld metal containing zirconium is less sensitive to the solidification cracking than the weld metal containing chromium does. (3) The self restraint test method shows the same tendency in results as the external restraint test does.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.275-279
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• 1996

In this study, the effect of external restraint on the thermal stresses and thermal cracking mode in mass concrete are analysed using the two major factors affecting external restraint such as the ratio of width go height of the placed structure (L/H) and the elastic modulus of base structure (E). For this parametric study, many cases with different values of L/H and Er are analysed by the FEM program and the co-relationship of the those major factors is examined. To evaluate the effect of external restraint on the thermal behavior of placing structure, internal restraint stress caused by temperature difference is subtracted from total thermal stress. In the case of small value of L/H or Er, it shows as internally restricted mode indicating maximum tensile stress in surface at early age, and the external restraint makes the possibility of thermal cracking higher. However, in the case of the large values of L/H and Er, the crack index at center is smaller than at surface due to the effect of external restraint. Thus, the initial location of the thermal crack is shifted from the surface to the center and the resulting crack is formed at later age.

• Journal of Korean Academy of Nursing
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• v.31 no.1
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• pp.43-54
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• 2001

The purpose of this study was to investigate the relationship between health locus of control (HLOC) and the eating behaviors in obese high school girls. The sample consisted of 262 obese high school girls in Seoul and Kangwon-Do. The results of this study were as follows: 1. The average scores of HLOC were HLOC- Internal; 4.06, HLOC-External; 2.47, and HLOC-Chance; 2.15. 2. The average scores of eating behavior factors were Disinhibition ; 2.91, Hunger ; 2.73, Dietary Restraint ; 2.55. 3. The HLOC-Internal and eating behavior (dietary restraint, disinhibition and hunger) were correlated positively. The HLOC- Chance and hunger was correlated positively. But HLOC-Chance and other eating behavior factors (dietary restraint & disinhibition) were not correlated in the level of statistical significances. The HLOC-External and eating behavior (dietary restraint, disinhibition and hunger) were correlated positively. 4. There was not a significant difference in HLOC depending on the existence of an obese sibling. There were significant differences in HLOC-Internal and HLOC- External depending on the evaluation of one's body figure. 5. There were significant differences in disinhibition and hunger depending on the existence of obese sibling. Also, there were significant difference in dietary restraint according to self perception of who is obese or not (t=3.342, p=.001). This study has shown a correlation between HLOC and eating behavior. As a result of these findings, clinical and school nurses should be involved in management and counselling obese girls concerning individual health locus of control and eating behavior.

• Structural Engineering and Mechanics
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• v.35 no.6
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• pp.699-715
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• 2010

This paper investigates the structural responses of axially restrained steel beams under fire conditions by a nonlinear finite element method. The axial restraint is represented by a linear elastic spring. Different parameters which include beam slenderness ratio, external load level and axial restraint ratio are investigated. The process of forming a mid-span plastic hinge at the mid-span under a rising temperature is studied. In line with forming a fully plastic hinge at mid-span, the response of a restrained beam under rising temperature can be divided into three stages, viz. no plastic hinge, hinge forming and rotating, and catenary action stage. During catenary action stage, the axial restraint pulls the heated beam and prevents it from failing. This study introduces definitions of beam limiting temperature $T_{lim}$, catenary temperature $T_{ctn}$ and warning time $t_{wn}$. Influences of slenderness ratio, load level and axial restraint ratio on $T_{lim}$, $T_{ctn}$ and $t_{wn}$ are examined.

• Child Health Nursing Research
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• v.9 no.2
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• pp.123-130
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• 2003

Purpose: The purpose of this study was to investigate the relationship between health locus of control(HLOC) and eating behavior in obese middle school girls. Method: The sample consisted of 170 obese middle school girls in Seoul. Result: 1. The average scores of HLOC were HLOC-Internal ; 4.11, HLOC-External ; 2.45, HLOC-Chance ; 2.09. 2. The average scores of eating behavior factors were Disinhibition ; 2.69, Dietary Restraint ; 2.67, Hunger ; 2.55. 3. The HLOC-Internal and eating behavior(dietary restraint and hunger) were correlated positively. The HLOC-Chance and disinhibition was correlated positively. But HLOC-Chance and dietary restraint was correlated negatively. The HLOC-External and eating behavior(dietary restraint, disinhibition and hunger) were correlated positively. 4. There was not a significant difference in HLOC depending on the demographic characteristics(grade, degree of obesity, father & mother's body shape, existence of obese sibling). There were significant differences in HLOC-Internal and HLOC-External according to thinking about oneself who is obese or not. 5. There was not a significant difference in eating behavior depending on the demographic characteristics(grade, degree of obesity, father & mother's body shape, existence of obese sibling, perception of oneself as a obese). Conclusion: This study has shown a correlation between HLOC and eating behavior. As a result of these findings, clinical and school nurses should be involved in management and counselling of obese girls concerning individual health locus of control and eating behavior.

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.165-167
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• 2001

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.1
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• pp.44-48
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• 2016

In this paper, we analyzed the operating characteristics of a ventilating fan due to overload and overheating. The experiment assumed the forcible restraint of the blade due to external objects and the aging process. We analyzed the experimental temperature and operating characteristics of the three places in the interior of the ventilating fan. As a result of the analysis, the temperature distribution was highest to lowest in the following order: the thermal fuse, the motor inside, and the above winding. There was smell of burning enamel in the restraint experiment. Following the thermal fuse operation, the insulation of motor winding was good. In the case of rated voltage and new ventilating fan restrained for about 4hours, and the results of restraint experiments in the presence or absence of the thermal fuse, no risk of deformation or fire due to overheating was identified. Henceforward, ignition hazard experiments will be required for additional factors of aging, pollution, and defective insulation.

• Journal of Welding and Joining
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• v.30 no.5
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• pp.51-56
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• 2012

The purpose of this study is to evaluate the distortion and the residual stress of GTA tubular welds between tube and head. In order to do it, the heat input model for GTA welding process was first developed by experiment and FE analyses. The welding distortion and the residual stress distribution of the tubular welds according to welding pass and various restraint degrees were evaluated by using FEA with the heat input model. From FEA results, it was found that the residual stress and the radial distortion at the weld toe of tube part decrease with a decrease in the number of welding pass. However, the maximum residual stresses in each direction of tubular welds are almost constant regardless of the external restraint degree. It was mainly due to the high internal restraint of the welds.