• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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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.

• 콘크리트학회지
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• 제8권5호
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• pp.111-122
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• 1996

본 연구에서는 매스콘크리트의 외부구속도의 특성을 검토하기 위하여, 타설높이를 1.0m로 고정시킨 상태에서 타설블럭의 밑면길이와 타설높이와의 비(L/H), 하부 구속체의 탄성계수($E_r$) 등 매스콘크리트 구조물에서 특히 외부구속에 영향을 미치는 인자를 대상으로 parameter study를 실시하여 각 인자가 온도응력에 미치는 영향을 검토하고 각 인자간의 상호 영향도에 대해서도 검토하였다. 검토결과, 외부구속에 의해 발생하는 응력은 단면 높이방향으로 거의 직선분포를 이루고 있으며, L/H나 구속체 탄성계수의 크기에 따라서도 다르고 타설한 콘크리트의 강도발현에 따른 탄성계수의 증가 및 체적변화로 이해서 재령별로도 그 영향이 각각 다르다는 것을 알았다. 또한, 외부구속은 축방향구속과 휨방향구속으로 나누어 평가할 수 있으며, 외부구속이 약한 경우는 휨방향구속이 탁월하고, 외부구속이 강한 경우는 축방향구속이 탁월하다는 것을 알았다. 그리고타설높이 H를 1.0cm로 제한 시킨 경우에 ACI 207 위원회법으로 계산한 결과를 본 해석결과와 비교한 결과, ACI위원회법으 외부고속이 약한 경우에는 본 해석결과보다 큰 값으로 평가하고, 외부구속이 강한 경우에는 작게 평가하고 있음을 알았다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1995년도 특별강연 및 춘계학술발표 개요집
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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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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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.

• 대한간호학회지
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• 제31권1호
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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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• 제35권6호
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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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• 제9권2호
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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.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2001년도 춘계학술발표대회 개요집
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• pp.165-167
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• 2001

• 조명전기설비학회논문지
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• 제30권1호
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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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• 제30권5호
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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.