• Physical Therapy Rehabilitation Science
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• v.5 no.2
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• pp.70-77
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• 2016

Objective: The purpose of this study was to compare the activation of trunk and gluteal muscles during bridge exercises with a sling (BS), single-legged bridge exercise with a sling (SBS), single-legged bridge exercise (SB), and general bridge exercise (GB). Design: Cross-sectional study. Methods: Twenty-five healthy participants (19 males and 6 females, aged 27.8 [4.78]) voluntarily participated in this study. In the bridging exercise, each subject lifted their pelvis with their legs and feet in contact with the sling or normal surface. The electrical activities of the erector spinae (ES), gluteus maximus (GM), external oblique (EO), and internal oblique (IO) muscles during the bridging exercises on the 2 surfaces were measured using surface electromyography. Subjects practiced each of the four bridge condition three times in random order and average values were obtained. Results: On the ipsilateral side, activities of the IO, EO, and ES during SBS was significantly higher than those during BS, SB, and GB (p<0.05). Activities of the IO and EO during SB was significantly higher than those during BS and GB (p<0.05). On the contralateral side, activities of the GM and EO during SB and SBS was significantly higher than that during BS and GB (p<0.05). These results verify the theory that the use of sling and single leg lift increases the activation trunk and gluteal muscles during bridging exercises. Conclusions: The single-legged bridge exercise with a sling can be recommended as an effective method to facilitate trunk and gluteal muscle activities.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1A
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• pp.31-37
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• 2012

The phase distribution in concrete materials strongly affects its material properties. It is important to identify the spatial distribution of void in concrete because the void in concrete materials affects mechanical behavior and permeability significantly. Therefore, a proper method to describe the void distribution of a material is needed. In this research, CT(computed tomography) is used to examine and to quantify the void distribution of porous concrete specimens. 3D concrete digital specimens are created by subsequent stacking of 2D cross-sectional images from CT. Then, probability distribution functions such as two-point correlation, lineal-path and two-point cluster functions are used for void distribution characterization. It is confirmed that probability distribution functions obtained from CT images are effective in characterizing void distributions including the anisotropy and percolation.

• Nutrition Research and Practice
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• v.5 no.4
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• pp.322-328
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• 2011

The aim of this study was to use the Healthy Eating Index-2005 (HEI-2005) to assess diet quality and determine the relationship between the HEI-2005 and the energy and nutrient intakes of adolescents. A cross-sectional study was conducted on 1,104 healthy adolescents, mean age of $15.8{\pm}1.24$ years. Dietary intake was measured with the 24-hour dietary recall method, and dietary quality was assessed by means of the HEI-2005. Diet quality scores ranged from 23.7 to 77.5. The mean score was found to be $51.5{\pm}9.07$ according to the HEI-2005. There were no differences according to gender, 42.8% had a poor diet and 57.2% had a diet that needs improvement. No subjects had a "good diet". Lower mean subgroup scores were found for whole grains, total vegetables, total fruits, dairy products, and meat and beans. Fruits and vegetables scores were significantly high in girls, whereas sodium, oil, and meat and beans scores were significantly high in boys. Total HEI-2005 scores were increasingly associated with parental education level when age and gender were adjusted. There was a negative correlation between HEI-2005 scores and age, total energy intake, and fat intake. Positive correlation was only observed in the HEI-2005 scores for protein and dietary fibre intakes. Consequently, the overall diet quality and nutritional habits of Turkish adolescents need modification and improvement. In the family, measures should be initiated by the government, including advertisements and campaigns.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.795-805
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• 1994

This paper presents the analytical results for the prediction of elastical local buckling stress of fiber reinforced plastic (orthotropic) structural shapes manufactured from pultrusion process. In the derivation, existing Bleich's approach which was originally derived for the isotropic structural shapes was extended and non-dimensionalized parameters which can simplify the numerical calculations were adopted. Analytical results were compared with reported closed-form solutions and experimental results. It is graphically shown that the results can be used effectively to predict the local buckling stress of pultruded fiber reinforced plastic structural shapes. Numerical results were presented graphically to estimate the local buckling stress of various cross-sectional dimensions and lengths of columns. In addition, limits of width to thickness ratio of flange and web of pultruded structural shapes were suggested in which material failure or overall buckling occurs prior to local buckling.

• Fire Science and Engineering
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• v.26 no.6
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• pp.45-50
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• 2012

The spalling causes the sever reduction of the cross sectional area with the exposure of the reinforcing steel, which originates a problem in the structural behaviour. By coating surface of high strength concrete with fireproof mortar, the high strength concrete is protected from the spalling in fire and the method to constrain the temperature increase of steel bar within the concrete. The purpose of this study is to investigate the temperature history properties of lightweight mortar using perlite and polypropylene fiber for fire protection covering material. For this purpose, selected test variables were the contents and length of polypropylene fiber. As a result of this study, it has been found that addition of polypropylene fiber to mortar modifies its pore structure and this causes the internal temperature to rise. And it has been found that a new lightweight mortar can be used in the fire protection covering material.

• ETRI Journal
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• v.27 no.3
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• pp.304-311
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• 2005

We report on the fabrication of an AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor (PHEMT) using a dielectric-defined process. This process was utilized to fabricate $0.12\;{\mu}m\;{\times}\;100 {\mu}m$ T-gate PHEMTs. A two-step etch process was performed to define the gate footprint in the $SiN_x$. The $SiN_x$ was etched either by dry etching alone or using a combination of wet and dry etching. The gate recessing was done in three steps: a wet etching for removal of the damaged surface layer, a dry etching for the narrow recess, and wet etching. A structure for the top of the T-gate consisting of a wide head part and a narrow lower layer part has been employed, taking advantage of the large cross-sectional area of the gate and its mechanically stable structure. From s-parameter data of up to 50 GHz, an extrapolated cut-off frequency of as high as 104 GHz was obtained. When comparing sample C (combination of wet and dry etching for the $SiN_x$) with sample A (dry etching for the $SiN_x$), we observed an 62.5% increase of the cut-off frequency. This is believed to be due to considerable decreases of the gate-source and gate-drain capacitances. This improvement in RF performance can be understood in terms of the decrease in parasitic capacitances, which is due to the use of the dielectric and the gate recess etching method.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.812-818
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• 2001

This paper proposes an optimum design method of structural and control systems, taking a 2-D truss structure as an example. The structure is supposed to be subjected to initial static loads and disturbances. For the structure, a FEM model is formed, and using modal transformation, the equation of motion is transformed into that of modal coordinates in order to reduce the D.O.F. of the FEM model. The structure is controlled by an output feedback $H^$\infty$$ controller to suppress the effect of the disturbances. The design variables of the simultaneous optimal design of control-structure systems are the cross sectional areas of truss members. The structural objective function is the structural weight. The control objective function is the $H^$\infty$$ norm, that is, the performance index of control. The second structural objective function is the energy of the response related to the initial state, which is derived from the time integration of the quadratic form of the state in the closed-loop system. In a numerical example, simulations have been carried out. Through the consideration of structural weight and $H^$\infty$$ norm, an advantage of the simultaneous optimum design of structural and control systems is shown. Moreover, while the optimized performance index of control is almost kept, we can acquire better design of structural strength.

• Journal of Korean Academy of Nursing
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• v.35 no.1
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• pp.195-205
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• 2005

Purpose: This study was to identify the relationship between perceived stress, anger expression, and level of depression in cancer patients. Method: A cross-sectional descriptive study design was used. Data was collected by uestionnaires from 185 in- and out-patients who were diagnosed with cancer at 3 university hospitals and the National Cancer Center using Spielberger et al.’s Anger Expression Scale, Cohen, Kamarch & Mermelstein's Perceived Stress, and Derogatise's SCL-90. The data was analyzed using descriptive statistics, Pearson correlation coefficient, and stepwise multiple regression with SAS/PC. Result: The perceived stress in cancer patients indicated a significant positive correlation to anger-in(r=.288, p=.000), anger-out(r=.232, p=.001), and depression(r=.68, p=.000), but no significant correlation to anger-control. The anger-in of cancer patients showed a significant positive relationship to anger-out(r=.53, p=.000), and depression(r=.383, p=.000), but no significant correlation to anger-control. Anger-out showed a significantly negative correlation to anger-control (r=-.248, p=.001) and a positive correlation to depression (r=.240, p=.001). The most significant predictor which influenced depression in cancer patients was perceived stress, followed by anger-in and hobby, and these factors explained their depression with a variance of 54%. Conclusion: These results suggested that cancer patients with a high degree of perceived stress are likely to be high in anger-out and anger-in. Perceived stress and anger-in are major factors which affect depression in cancer patients.

• Journal of Korean Academy of Nursing
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• v.32 no.6
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• pp.792-802
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• 2002

This cross-sectional study was designed to explore the relationship among social support, experienced stressful life events and health behaviors of Korean undergraduate students, and validate the mediator effect of social support. Method: One thousand four hundred fifty-three undergraduate students were randomly selected from five universities located in the middle area of Korea. Result: The health behaviors of Korean undergraduates tend to have unhealthy patterns. In the case of the students living without family, experiencing more stressful life events and perceiving lower social support, health behaviors are poor. The relationship between perceived social supports, the frequency of the experienced stressful life events and the score of health behavior patterns is statistically significant. After controlling the effect of social support, the correlation coefficient between the frequency of experienced stressful life events and the score of health behavior patterns was slightly lower. The score of health behaviors between the group with an extremely high score of social support and the group with an extremely low score were statistically significantly different. Conclusion: Future studies need to be pursued to develop various strategies such as a health education programs and counseling programs for health maintenance and health promotion of undergraduates.

• Korean Journal of Adult Nursing
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• v.15 no.2
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• pp.205-214
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• 2003

Purpose: This study was conducted to examine the nurses' knowledge about and attitude toward cancer pain management. Method: Study subjects of this retrospective cross-sectional survey study were 343 nurses sampled conveniently in a tertiary teaching hospital in Seoul. Seven measurement tools were used to collect data on demographic data, knowledge about and attitude toward cancer pain management, barrier to cancer pain management, knowledge about and concerns for the opioid use, and professional education of cancer pain management. Result: Nurses showed knowledge deficit when their knowledge on the cancer pain management and the opiod use was evaluated using two case scenarios and the 15-item questionnaire respectively. Ninety-five percent of the nurses believed that cancer pain management is a major problem. However, inadequate staff knowledge of pain management was rated as the single most important barrier to adequate pain management by 20.4% of nurses. Only 10.9% and 23.2% of the nurses replied that nursing school's education and professional education in cancer pain management respectively, were adequate. Conclusion: This study confirms the existence of knowledge deficits and attitudinal barriers among Korean nurses that can impede cancer pain management. This study suggests a need for professional education for nurses on cancer pain management.