• Journal of Astronomy and Space Sciences
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• 제32권4호
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• pp.311-315
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• 2015

In this study, we estimated the topside scale height of plasma density (Hm) using the Swarm constellation and ionosondes in Korea. The Hm above Korean Peninsula is generally around 50 km. Statistical distributions of the topside scale height exhibited a complex dependence upon local time and season. The results were in general agreement with those of Tulasi Ram et al. (2009), who used the same method to calculate the topside scale height in a mid-latitude region. On the contrary, our results did not fully coincide with those obtained by Liu et al. (2007), who used electron density profiles from Arecibo Incoherent Scatter Radar (ISR) between 1966 and 2002. The disagreement may result from the limitations in our approximation method and data coverage used for estimations, as well as the inherent dependence of Hm on Geographic LONgitude (GLON).

• 한국조경학회지
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• 제18권1호
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• pp.69-79
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• 1990

This study intends to define the concept of human scale and visual preference which is frequently being used by environmental designers, and to explore the dimension of buildings and courtyards which is perceived as "human scale" and "visually preferable" by users (college students). As the subjects of this experiment were college students, "human scale" and "visual preferenoe" that were professional terms must be changed to understandable and compatible concept. The compatible concept for human scale was defined as the degree of friendliness and comfort, and that for visual preference was declined as the degree of like or dislike. The subjects thought that buildings with the height of 2.73 ∼5. 83 storides, the length of 27.44∼44.00m and the height ratio of 1.81 ∼5.41 were in human scale, and that buildings with height 2.60 ∼ 6.00 stories, the length of 25.7∼55.00 and the height ratio of 1.32∼6.41 were visually preferred. The block game used in this study was Proved to he a reliable and valid experimental method.

• 한국환경과학회지
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• 제11권3호
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• pp.155-160
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• 2002

Using measured data at Daegu by tethersonde for the period of 1984∼1987, we have investigated the lower atmospheric boundary layer structure including relationships between inversion layer and meteorological factors(wind and temperature), and the inversion strength and inversion height. The inversion layer was defined from the vertical temperature profile and its strength was analyzed with the wind shear as well as the vertical temperature gradient. From October to January, measured inversion layer isn't destroyed, however, in June, after sun rise, it is destroyed by surface heating and mixed layer is developed from surface. According to Pasquill stability classes, the moderately stable cases dominated. It's the larger vertical temperature gradient the lower SBL height. We have introduced B(bulk turbulence scale) which indicated SBL height. It's larger B, the higher SBL height and vice versa. It was noted that the bulk turbulence scale (B) is appropriate to determine the stable boundary layer height.

• Geomechanics and Engineering
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• 제34권4호
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• pp.461-472
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• 2023

A box scale affects the shear behavior of soils in the direct shear test. The purpose of this study is to investigate the scale effect on the shear behavior of dilative granular materials by testing specimens of different heights placed in a type C shear box. Experimental tests were performed on specimens composed of glass beads with different heights and equal initial void ratios. Results showed that the peak friction and dilation angles linearly increased with the specimen height; however, the residual friction angle remained relatively constant. Similarly, the shear stiffness increased with the specimen height, rapidly reaching its peak state. Height does not have a significant effect on the total volume changes; nevertheless, a high aspect ratio can be assumed to result in global and homogeneous failure. The results and interpretations may be used as reference for recommending shear box scale in direct shear tests.

• 천문학회보
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• 제37권2호
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• pp.110.2-110.2
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• 2012

We investigate a cool loop and a dark lane over a limb active region on 2007 March 14 by the Hinode/EUV Imaging Spectrometer (EIS). The cool loop is clearly seen in the EIS spectral lines formed at the transition region temperature (log T = 5.8). The dark lane is characterized by an elongated faint structure in coronal spectral lines (log T = 5.8 - 6.1) and rooted on a bright point. We examine their electron densities, Doppler velocities, and non-thermal velocities as a function of distance from the limb using the spectral lines formed at different temperatures (log T = 5.4 - 6.4). The electron densities of the cool loop and the dark lane are derived from the density sensitive line pairs of Mg VII, Fe XII, and Fe XIV spectra. Under the hydrostatic equilibrium and isothermal assumption, we determine their temperatures from the density scale height. Comparing the scale height temperatures to the peak formation temperatures of the spectral lines, we note that the scale height temperature of the cool loop is consistent with a peak formation temperature of the Mg VII (log T = 5.8) and the scale height temperature of the dark lane is close to a peak formation temperature of the Fe XII and Fe XIII (log T = 6.1 - 6.2). It is interesting to note that the structures of the cool loop and the dark lane are most visible in these temperature lines. While the non-thermal velocity in the cool loop slightly decreases (less than 7 km $s^{-1}$) along the loop, that in the dark lane sharply falls off with height. The variation of non-thermal velocity with height in the cool loop and the dark lane is contrast to that in off-limb polar coronal holes which are considered as source of the fast solar wind. Such a decrease in the non-thermal velocity may be explained by wave damping near the solar surface or turbulence due to magnetic reconnection near the bright point.

• 한국공작기계학회논문집
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• 제13권4호
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• pp.37-43
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• 2004

A measurement accuracy of theodolite system may be affected by a measurement environment, a measurement distance change and so on. This study was performed for measuring an accuracy when the height of scale bar is changed 0.05m, 0.5m, 1m and 1.5m under the distance 3m between two theodolites, the distance 4m from the theodolite system to scale bar and the distance 5m from the thodolite system to the horizontal target bar. And we could know that the best height is 0.05m and 1m.

• 대한한방소아과학회지
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• 제37권4호
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• pp.1-14
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• 2023

Objectives This study aimed to evaluate the correlation between pediatric weakness scale scores and growth indices. Furthermore, we intended to calculate the cut-off values for diagnosing Kidney Weak Children through growth indices. Methods A total of 193 patients, aged 6 - 12 years, underwent both the pediatric weakness scale and bone age assessment, and the correlations between the pediatric weakness scale and growth indices were analyzed. Moreover, the cut-off values for diagnosing Kidney Weak Children were calculated. Differences in bone age and predicted height between the normal group and Kidney Weak Children, classified according to the calculated cut-off values, were analyzed. Results The weakness of the Shin or kidney system was significantly correlated with the height percentile, weight percentile, differences in current height percentile and mid parental height percentile, differences in predicted height and mid parental height, and differences in bone age and chronological age. When the criteria for diagnosing Kidney Weak Children is set at "height percentile of ≤25% and weight percentile of ≤25%", the sensitivity and specificity of the cut-off value were maximized. The cut-off values for weakness of the Shin or kidney system were 9 in children aged 6 - 9 years and 10 in children aged 10 - 12 years. Conclusions To diagnose Kidney Weak Children, the cut-off values of weakness of the Shin or kidney system were 9 in children aged 6 - 9 years and 10 in children aged 10 - 12 years.

• 대한기계학회논문집B
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• 제23권11호
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• pp.1363-1370
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• 1999

A study of scaling and heat transfer has been carried out for a vertical tube evaporator in which $CaSO_4$ saturated water flows upward. Experimental apparatus including vacuum chambers and heaters has been designed and manufactured to study scaling phenomena for three different pressures(1atm, 0.27atm and 0.16atm). Overall heat transfer coefficients have been measured and shown to decrease with time as scaling proceeds. After the end of experiments, the vertical tube has been cut to measure the thickness of scale at different heights. Below the height where the bulk fluid temperature does not reach saturated temperature, the thickness of scale increases, however, beyond that height occurring saturated condition, the thickness does not vary much or even decreases a little. The measured fouling resistances also support these variations of scale thickness.

• 동의신경정신과학회지
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• 제13권2호
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• pp.93-100
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• 2002

Objects and Methods : BDl, STAI and Self-Esteem scale were completed by 28 female subjects who composed of nurses of Kyung Hee Medical Center and students of Kyung Hee Oriental Medical college. At the same time, current weight, height and BMI(Body Mass Index), ideal weight, height and BMI, the difference of current weight and ideal weight, the difference of current height and ideal height, and the difference of current BMI and ideal BMI were measured. Result : 1. There was a significant difference between obese and normal weight group in the difference between the current weight and the ideal weight. The difference of the obese group were higher than the normal weight group. 2. There was a significant difference between obese and normal weight group in the mean BDI score. The mean BDI score of the obese group were higher than that of the normal weight group. 3. There was no significant difference between obese and normal weight group in the mean STAI score. 4. There was no significant difference between obese and normal weight group in the mean Self-Esteem Scale score. Conclusion : There are a tendency; the more weight, the more depression in women.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.169-177
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• 1997

An experimental study has been conducted at an intermediate scale to study the effect of a cross flow on a purely buoyant fire. Video taping of the flame and post processing of the images by means of a novel technique provide a contour of a mean flame for all cases studied. This flame contour allows the determination of a mean flame length and a mean flame height. The mean flame length and height are recorded as functions of the forced flow velocity. Three dimensional flow patterns are formed in the flame trailing edge affecting both the mean flame length and height. The three dimensional patterns are studied systematically as functions of the cross flow velocity to quantify the effect of confinement on the flame geometry.