• Atmosphere
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• v.20 no.4
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• pp.427-436
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• 2010

The single-scattering optical properties of ice crystals in cirrus clouds by the aircraft measurement data were investigated, and the radiative equilibrium temperatures and radiative fluxes were calculated and analyzed by radiative convective model with the variations of ice crystal habits and sizes in cirrus clouds. The homogeneous cloud is assumed to be in the layer 200~260 hPa with an ice crystal content of $10gm^{-2}$ for the flux calculation. The profiles of temperature, humidity, and ozone typical of mid-latitude summer are used. The surface albedo is assumed to be 0.2 for all spectral bands and the cosine of solar zenith angles is 0.5. The result of radiative equilibrium temperature at surface was less than surface temperature of the standard atmosphere data in case of smaller effective ice crystal size and larger optical thickness. The column, aggregation and plate in 6 ice crystal habits were the most effective in positive greenhouse effect and bullet-4 was the worst in it. At the surface, the maximum difference of equilibrium temperature by 6 kinds of ice crystal habits were about 3~15 K with 30 sample aircraft measurement data.

• Atmosphere
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• v.17 no.3
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• pp.291-298
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• 2007

The precipitable water vapors (PWVs) obtained from Global Positioning System (GPS) and Microwave Radiometer (MWR) measurements have been compared for validation of precision of the GPS PWV at Daegwallyoung station for 21 days from Sep. 30 to Oct. 20, 2006. The GPS PWV is estimated using the delay of GPS signals due to the water vapor in the atmosphere with a local mean temperature equation, called HP model, and the MWR PWV by the combinational radiance observation of two channels (23.8 and 31.4 GHz). During the co-observation period, the MWR and GPS PWV show a similar trend, and the bias between the PWVs is 1.7 mm on average. When the bias is removed, the PWV of GPS gives good agreement with that of MWR, having about 1 mm for both the standard deviation and RMS error between the GPS and MWR PWV.

• Atmosphere
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• v.18 no.3
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• pp.207-224
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• 2008

Severe downslope windstorms observed at Gangneung, Korea in the springtime during the last 30 years are studied to understand their generation mechanisms. 92 severe wind cases are selected for which the maximum instantaneous wind speeds exceed two standard deviation of total mean plus ($18.7ms^{-1}$). They are categorized into the three mechanisms (hydraulic jump, partial reflection, and critical-level reflection) proposed in previous studies based on the flow condition, which is calculated using the wind and temperature profile observed at one upstream rawinsonde station, Osan. Among the three, partial reflection is found to be the most frequent mechanism for the last 30 years (1976 - 2005). To understand the role of inversion in generating severe downslope windstorms, horizontal velocity perturbation was calculated analytically for the atmosphere with an inversion layer. It turned out that the intensity of downslope wind was increased by inversion layer of specific heights, which are well matched with the observations. For better understanding the generation mechanisms, two-dimensional numerical simulations are conducted for the 92 severe wind cases using the ARPS model. In most simulations, surface wind speed exceeds the value of the severe-wind criterion, and each simulated case can be explained by its own generation mechanism. However, in most simulations, the simulated surface wind speed is larger than the observed, due to ignoring the flow-splitting effect in the two-dimensional framework.

• Journal of the Korean Society of Costume
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• v.57 no.2 s.111
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• pp.143-154
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• 2007

This study's purpose is how express gender image according to sex in editorial fashion photography. This study's objectives are the women's magazine Vogue, Harper's Bazaar and man's magazine GQ, Esquire published 2000-2005 within the country. The photography was classified with established a standard based on the precede studies. The photo is classified Gender image according to dress and its ornaments, model character and atmosphere by Sex Expression of femininity woman has exposure of body parts and emphasizing thin eyebrows and red lips, soft and mild image, modest and static pose. Man expressed femininity used ladylike color and pattern, erotic exposure of body and long hair style. Commonly emphasizing red lips, natural background of flower plant, S-line. For expression of masculinity man and woman are used masculinity item, short hair-style and thick eyebrows. And also emphasize square like chin and shoulder. Specially, woman used direct silhouette to conceal soft body curved line. The expressions of androgynous woman and man are colorful dress and make-up. Woman emphasized male face to show and man expressed soft image through hull of abundant material of fur. All two sex selected method that conceal body curved line and face to express sexless. Hiding characteristics of body and face make indistinct of sex. The gender is affected by atmosphere such as model and illumination background as much as clothes because of the editorial fashion photography.

• Atmosphere
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• v.21 no.3
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• pp.311-317
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• 2011

Aerosol optical properties from the radiation measurements by SKYNET PREDE skyradiometers, POM-01 and POM-02 were compared during the inter-calibration campaign at Seoul in February 2009. The monochromatic solar flux at the top of the atmosphere ($F_0$) gave a relative standard deviation (RSD) of 9-10% for both instruments. This comparatively high value of RSD was probably because $F_0$ was determined at short time intervals, in the morning and afternoon, using the measurements made in the polluted environment of Seoul. Although POM-02 was more effective in tracking the solar radiation, aerosol optical depths (AODs) from the two instruments were very similar after the cloud screening procedure. The squared correlation coefficients ($R^2$) of single scattering albedo (SSA) and real and imaginary refractive indices between the two instruments was around 0.5 but increased to 0.7-0.8 when only using AOD greater than 0.4. Nevertheless, mean values of the Angstrom exponent, SSA, and the imaginary refractive index of POM-02 were higher than those of POM-01.

• Journal of the Korean Home Economics Association
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• v.28 no.4
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• pp.155-176
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• 1990

The purpose of this study is to investigate the influential factors to home management ability of mothers and their unmarried daughters through researching the relationship of their home management ability. It would provide the basic data for the direction of Home Economics Education. The subjects were 653, from 20 to 30 years of unmarried women and their mothers in Chonbuk province. The questionaire was used to measure their Home Management ability. The measured areas were planing, creativity, consumption management, housework, evaluation, and human relation. The question items were respectively 6 and totally 36. Spss was used for the statistic. Frequency, Percentage, Means, Standard Deviation were used for general understanding. For data analysis, F-test, Pearson Product-moment Correlation, Duncan's Multiple Range Test, Stepwise Multi-regression Analysis were used. Lastly, the research pattern was examined by Path Analysis. The results were as follows. 1. The importnat influential factors to mother's home management ability were their schooling level and their perceived socio-economic status among the general factors(age, shooling level, perceived socio-economic status) and the family atmosphere factors(monthly income, family type). 2. The important influential factors of unmarried daughter's home management ability were the monthly income of their family and the socio-economic status perceived by them, among their mother's general factors, family atmohphere factors, their own general factors(age, schooling level, perceived socio-economics status, occupation, growing place). 3. The influence of mother's home management ability on unmarried daughter's home management ability was much more remarkable than mother's general factors, family atmosphere factors and unmarried daughter's general factors.

• Korean Journal of Health Education and Promotion
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• v.17 no.2
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• pp.125-149
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• 2000

The purpose of this study was practiced to investigate factors affecting dental hygienists's stress. The results executed by percentage and Likert scale (on a scale of 5) producing a mean standard deviation, T-test, one way ANOV A and person correlation coefficient using SPSS according to purpose of study. The results of study were as follows: 1. Mean point of stress from administration system dental hygienists's was 3.49 2. The dental hygienists's job place was significantly related to stress from duty volume (p=0.000), stress from personal relation(p=0.028) and stress from atmosphere of job(p=0.000). 3. The dental hygienists's career was significantly related to stress from safe job. 4. The dental hygienists's grade in rank was significantly related to stress from pride ＆ self-conceit. 5. The number of colleague worked public health center was significantly related to stress from duty volume. 6. There is a significant relationship between stress from duty volume and stress from conflict of job(p〈0.01, r=0.280). There is a significant relationship between stress from dissatisfaction and stress from personal relationship(p〈0.001, r=0.396). There is a significant relationship between stress from pride ＆ self-conceit and stress from personal relationship(p〈0.001, r=0.423). There is a significant relationship between stress from personal relationship and stress from atmosphere of job(p〈0.001, r=0.662).

• Journal of the Korean Society of Safety
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• v.10 no.3
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• pp.68-80
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• 1995

A series of parametric calculations have been performed in order to investigate the short-term and short-range plume and puff behavior of toxic gaseous and solid pollutant dispersion in an open atmosphere. The simulation is made by the use of the computer program developed by this laboratory, in which a control-volume based finite-difference method is used together with the SIMPLEC algorithm for the resolution of the pressure-velocity coupling appeared In Wavier-Stokes equation. The Reynolds stresses are solved by the standard two-equation k-$\varepsilon$ model modified for buoyancy together with the RNG(Renormalization Group) k-$\varepsilon$ model. The major parameters considered in this calculation are pollutant gas density and temperature, the relative velocity of pollutants to that of the surrounding atmospheric air, and particulate size and density together with the height released. The flow field is typically characterized by the formation of a strong recirculation region for the case of the low density gases such as $CH_4$ and air due to the strong buoyancy, while the flow is simply declining pattern toward the downstream ground for the case of heavy molecule like the $CH_2C1_2$and $CCl_4$, even for the high temperature, $200^{\circ}C$. The effect of gas temperature and velocity on the flow field together with the particle trajectory are presented and discussed in detail. In general, the results are physically acceptable and consistent.

• Journal of Astronomy and Space Sciences
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• v.33 no.4
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• pp.273-278
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• 2016

December 2009 was one of the quietest (monthly Ap=2) months over the last eight decades. It provided an excellent opportunity to study the day-to-day variability of the F2 layer with the smallest contribution due to geomagnetic activity. With this aim, we analyze hourly values of the F2-layer critical frequency (foF2) recorded at 18 ionosonde stations during the magnetically quietest (Ap=0) days of the month. The foF2 variability is quantified as the relative standard deviation of foF2 about the mean of all the "zero-Ap" days of December 2009. This case study may contribute to a more clear vision of the F2-layer variability caused by sources not linked to geomagnetic activity. In accord with previous studies, we find that there is considerable "zero-Ap" variability of foF2 all over the world. At most locations, foF2 variability is presumably affected by the passage of the solar terminator. The patterns of foF2 variability are different at different stations. Possible causes of the observed diurnal foF2 variability may be related to "meteorological" disturbances transmitted from the lower atmosphere or/and effects of the intrinsic turbulence of the ionosphere-atmosphere system.

• Wind and Structures
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• v.17 no.4
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• pp.361-377
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• 2013

Wall functions have been widely used in computational fluid dynamics (CFD) simulations and can save significant computational costs compared to other near-wall flow treatment strategies. However, most of the existing wall functions were based on the asymptotic characteristics of near-wall flow quantities, which are inapplicable in complex and non-equilibrium flows. A modified wall function is thus derived in this study based on flow over a plate at zero-pressure gradient, instead of on the basis of asymptotic formulations. Turbulent kinetic energy generation ($G_P$), dissipation rate (${\varepsilon}$) and shear stress (${\tau}_{\omega}$) are composed together as the near-wall expressions. Performances of the modified wall function combined with the nonlinear realizable k-${\varepsilon}$ turbulence model are investigated in homogeneous equilibrium atmosphere boundary layer (ABL) and flow around a 6 m cube. The computational results and associated comparisons to available full-scale measurements show a clear improvement over the standard wall function, especially in reproducing the boundary layer flow. It is demonstrated through the two case studies that the modified wall function is indeed adaptive and can yield accurate prediction results, in spite of its simplicity.