• Wind and Structures
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• v.18 no.6
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• pp.651-668
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• 2014

Wind tunnel tests are conducted to investigate the wind loads on vertical fixed-roof cylindrical tanks with a very low aspect ratio of 0.275, which is a typical ratio for practical tanks with a volume of $100,000m^3$. Both the flat-roof tank and the dome-roof tank are investigated in present study. The first four moments of the measured wind pressure, including the mean and normalized deviation pressure, kurtosis and skewness of the pressure signal, are obtained to study the feature of the wind loads. It is shown that the wind loads are closely related to the behavior of flow around the structure. For either tank, the mean wind pressures on the cylinder are positive on the windward area and negative on the sides and the wake area, and the mean wind pressures on the whole roof are negative. The roof configurations have no considerable influence on the mean pressure distributions of cylindrical wall in general. Highly non-Gaussian feature is found in either tank. Conditional sampling technique, envelope method, and the proper orthogonal decomposition (POD) analysis are employed to investigate the characteristics of wind loads on the cylinder in more detail. It is shown that the patterns of wind pressure obtained from conditional sampling are similar to the mean pressure patterns.An instantaneous pressure coefficient can present a wide range from the maximum value to the minimum value. The quasi-steady assumption is not valid for structures considered in this paper according to the POD analysis.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.2
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• pp.314-325
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• 1999

The purposes of this study were to classify the types of consumers' emotion experienced in-store by shopping motivation and to examined the effects of store environmental factors on emotion and on shopping behavior. The questionnaires were administered to 330 women shopped in department store. Data from 299 women were analyzed by using frequency t-test and regression analysis by SPSS for windows PC program The results of this study were as follows : 1. The consumers' emotion experienced in -store were composed of five factors. But it could be divided by positive negative factors. 2. There was not significant difference in positive emotion between he Product Pu-rchasing Motive Group and the Window Shopping Motive Group. But there was significant difference n negative emotion between two groups. 3. It was found that the effect of environmental factors of apparel store on emotion was significant in both groups. Especially salespeoples' pressure significantly influenced negative emotion in both groups. 4. The emotion experienced in -store significantly influenced clothing shopping behavior.

• Clinical and Experimental Pediatrics
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• v.56 no.12
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• pp.526-533
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• 2013

Purpose: Obesity is an important risk factor for hypertension in adolescents. We investigated the relationship of obesity-related indices (body mass index [BMI], waist-to-height ratio [WHR], and body fat percentage [%BF]) with blood pressure and the hemodynamic determinants of blood pressure in Korean adolescents. Methods: In 2008, 565 adolescents, aged 12-16 years, were examined. The %BF of the participants was measured by bioelectrical impedance analysis. Echocardiography and brachial artery pulse tracing were used to estimate the stroke volume (SV), cardiac output (CO), total vascular resistance (TVR), and total arterial compliance (TAC). Results: We noted that BMI, WHR, and %BF were positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP). The positive correlation between BMI and blood pressure (SBP and DBP) persisted after adjustment for WHR and %BF. However, after adjustment for BMI, the positive associations between blood pressure (SBP and DBP) and WHR as well as %BF, were not noted. With regard to the hemodynamic factors, BMI, but not WHR and %BF, was an independent positive factor correlated with SV and CO. TVR had an independent negative association with BMI; however, it was not associated with WHR or %BF. Moreover, we noted that BMI, WHR, and %BF did not affect TAC. Conclusion: In Korean adolescents, BMI had an independent positive correlation with SBP and DBP, possibly because of its effects on SV, CO, and TVR. WHR and %BF are believed to indirectly affect SBP and DBP through changes in BMI.

• Journal of Biomedical Engineering Research
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• v.30 no.1
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• pp.18-22
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• 2009

Laser has been widely used in various fields of medicine. Recently, noninvasive low-level laser therapeutic medical devices have been introduced in market. However, low-level laser cannot deliver enough photon density to expect positive therapeutic results in deep tissue layer due to the light scattering property in tissue. In order to overcome the limitation, this study was aimed to develop a negative pressure applied low-level laser probe to optimize laser transmission pattern and therefore, to improve photon density in soft tissue. In order to evaluate the possibility of clinical application of the developed laser probe, ex-vivo experiments were performed with porcine skin samples and laser transmissions were quantitatively measured as a function of tissue compression. The laser probe has an air suction hole to apply negative pressure to skin, a transparent plastic body to observe variations of tissue, and a small metallic optical fiber guide to support the optical fiber when negative pressure was applied. By applying negative pressure to the laser probe, the porcine skin under the metallic optical fiber guide is compressed down and, at the same time, low-level laser is emitted into the skin. Finally, the diffusion images of laser in the sample were acquired by a CCD camera and analyzed. Compared to the peak intensity without the compression, the peak intensity of laser increased about $2{\sim}2.5$ times and FWHM decreased about $1.67{\sim}2.85$ times. In addition, the laser peak intensity was positively and linearly increased as a function of compression. In conclusion, we verified that the developed low-level laser probe can control the photon density in tissue by applying compression, and therefore, its potential for clinical applications.

• Korean Journal of Health Education and Promotion
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• v.13 no.2
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• pp.54-68
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• 1996

This study aimed at examining the risk factors of smoking behavior among middle school students and preparing school-based smoking prevention program. This study surveyed at February 1995 from 892 students at 3 middle schools in Seoul. The major findings of this study are follows; The proportion of current smoker among students in this study was 3.8%, and the proportion of intentions to smoking was 8.4%. At demographic variables male, pocket money of month was significantly positive association with smoking behavior, but economic status and education status of father were significantly negative association with smoking behavior. Results indicated that social influence variables(peer influence), alcohol, and positive attitudes of smoking were significantly positive association with smoking behavior. So implications for smoking prevention programs may be more effective at risk populations than using general adolescent population. Also ‘School-based smoking prevention programs’ may be learning social pressure resistance skills and giving knowledge and information about negative attitudes about smoking.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1921-1923
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• 2004

V-p characteristics and the discharge luminous characteristics in inhomogeneous $SF_6$ gas gap under the positive and negative lightning impulse voltages are presented. The test gap was composed of the plane-to-plane with a needle-shaped protrusion. The applied voltage and the predischarge current were measured by the electric field sensor and the shunt of 50 ${\Omega}$, respectively. The light emission signals were observed by a photomultiplier tube, and a high-speed camera. In a consequence, the dielectric strengths of $SF_6$ gas gap under positive lightning impulse voltages were independent of the gas pressure. In the presence of the positive polarity, the branches of discharge channel were created and the directions of the discharge paths were random. On the other hands, the discharge paths of the negative polarity were more thicker and brighter.

• Journal of the Korean School Mathematics Society
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• v.19 no.3
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• pp.217-238
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• 2016

The purpose of the study is to analyze the influence of the accomplishing pressure of teachers and parents on academic achievement in mathematics in accordance with the differences in the degree of intrinsic motivation in mathematics. The accomplishing pressure of teachers was meaningful on the academic achievement in mathematics in the analysis including the interaction of intrinsic motivation in mathematics. The students with high degree of intrinsic motivation were influenced in a negative manner. Meanwhile the students with middle or low degree of intrinsic motivation were influenced in a positive manner. The result implies that it is more important to consider the level of mathematical intrinsic motivation, when teachers accomplish an achievement pressure to improve academic achievement in mathematics. On the analysis including the interaction of intrinsic motivation of mathematics, the accomplishing pressure of parents showed positive effect in general on the academic achievement in mathematics. The students with high or middle degree of intrinsic motivation were highly influenced in a positive manner than the students with low degree of intrinsic motivation. The result implies the necessity of the implementation of continuous accomplishing pressure on students as the high degree of accomplishing pressure of parents leads to positive influence on the academic achievement in mathematics.

• Korean Journal of Community Nutrition
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• v.1 no.1
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• pp.61-70
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• 1996

Correlations of adolescents' blood pressure with dietary factors and blood or urinary electrolytes were investigated in this study. Through the screening for blood pressures of 960 middle school students aged 13-16 years, 30 students with the mean value of SBP and DBP above 96th percentile(high blood pressure group) and the other 30 with the mean blood pressure between 48th and 52th percentiles(normal blood pressure group) were selected as the subjects. SBP/DBP of the high and talc normal blood pressure groups were $141.8{\pm}9.0$ / $83.6{\pm}5.1$ mmHg and $116.4{\pm}3.5$ / $69.8{\pm}3.7 mmHg$, respectively. The average values of age, weight, height, BMI, degree of relative crude physical activity, and family income were not different between two groups. Among nutrients for which intakes were determined by 24 hour-recall and expressed as percent RDA, intakes of total and animal calcium were lower in the high blood pressure group compared to the normal, and were negatively correlated with both SBP and DBP even when the effects of related general and other dietary factors were excluded. Whereas energy, total, animal and vegetable protein, total and animal lipid, and riboflavin were higher in intake in the high blood pressure group than in fille normal, and they were in positive correlations with SBP and/or DBP. Vitamin A and ascorbic acid intakes were also negatively correlated with DBP, though ascorbic acid intake was not different between two groups. High blood pressure group preferred higher concentration of thin rice gruel than normal group and talc preferred salt concentrations was ill positive correlation with SBP. Serum and urinary levels of Ca, Mg, Ca/Mg ratio, Na, K and Na/K ratio did not show any differences between two groups. However serum Ca/Mg retio was in negative and se겨m Mg was ill positive correlations with SBP, and urinary Na excretion was negatively correlated with SBP. Calcium intake showed negative correlation with serum Ha and Na/K ratio. Our data indicated that dietary intake of Ca, energy, protein, lipid, vitamin A and C as well as salt preference were associated with blood pressure in adolescents. It might be assumed that Ca lowered blood pressure by increasing serum Ca/Mg ratio and decreasing serum Ca/K ratio though urinary excretion of Na.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.26 no.2
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• pp.11-18
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• 2020

Background: The purpose of this study is to examine the correlation between high heels and body imbalance among female college students in their twenties who mainly wear high heels and prevent associated problems. Methods: The subjects included 89 female college students in their twenties. They were measured in plantar pressure with a gait analyzer. Their legs were measured in length with a tape measure. Their pain intensity and pain frequency were measured in visual analog scale and in pain rating score. Results: There were statistically positive correlations between right leg length and low back pain frequency (p<.05) and negative correlations between the left hindfoot and low back pain frequency (p<.05). There were statistically positive correlations between right leg length and knee pain frequency (p<.05) and positive correlations between the ankle pain intensity and right leg length (p<.05). Conclusion: The stronger the pain was in the ankle, the stronger and more frequent their lumber pain was. When the pressure of the left heel was lower, the frequency of lumbar pain increased.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.1
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• pp.94-99
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• 2007

Many cases of acute cardiac shock and cardiac arrest in emergency room and ICU have been increasing. In this case, ECMO with centrifugal pump has been used generally. However, due to the heavy weight and big size, the system is not adequate for emergency cases. And other defects of this system are that membrane oxygenator's pressure is high and blood are exposed to the air. There was some tries of ECMO using pulsatile pump, but it was found that the weak point of these system is high peak pressure and hemolysis. The mechanism of twin pulsatile pump is that Membrane oxygenator Outlet Pump(MOP) make negative pressure when Membrane oxygenator Inlet Pump(MIP) provides high positive pressure, and the negative pressure will decrease positive pressure of Membrane Oxygenator. Our group analyzed this advantage through In-Vitro and 12 Cases In-Vivo test.