• Fire Science and Engineering
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• v.15 no.3
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• pp.1-6
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• 2001

This paper examined the variation in obscuration with height at indoor fire. The experiments were performed using a smoke box which is made for this job. It was found that the degree of smoke obscuration is depending upon the height. The obscurity at low position is less than that of high position. But there exist the deviation of obscurity at the position of air supply height.

• Atmosphere
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• v.17 no.3
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• pp.281-289
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• 2007

Micrometeorlogical and upper air observation have been conducted in order to determine the atmospheric boundary layer depth based on data from satellite and automatic weather systems. Terra/MODIS temperature profiles and sensible heat fluxes from the gradient method were used to estimate the mixed layer height over a coastal region. Results of the integral model were in good agreement with the mixed layer height observed using GPS radiosonde at Wolsung ($35.72^{\circ}N$, $129.48^{\circ}E$). Since the variation of the mixed layer height depends on the surface sensible heat flux, the integral model estimated properly the mixed layer height in the daytime. The buoyant heat flux, which is more important than the sensible heat flux in the coastal region, must be taken into consideration to improve the integral model. The vertical structure of atmospheric boundary layer can be analyzed only with the routine data and the satellite data.

• Proceedings of the KSRS Conference
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• v.2
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• pp.676-679
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• 2006

Mangrove crowns were delineated using active sensor LIDAR (LIght Detection And Ranging) data by a crown delineating model developed in this study. LIDAR data were acquired from airborne survey by a helicopter for the estuary of Macouria in the northeast coast of French Guiana. The canopy height image was derived from LIDAR vector data by calculating the difference between ground and non-ground data. The mangrove site in the study area was classified to three sectors by the time of mangrove settlement; Mangrove 1986, 2002 and 2003. The estimated crown of Mangrove 1986 was reliable defined for their size, number and volume because of larger crown size and bigger variation of crown height. The tree crown size of Mangrove 2002 and 2003 by the model was overestimated and the number of trees was much underestimated. The estimated crown was not for single crown but a crown group due to homogenous crown height and spatial resolution of LIDAR data. However the canopy height image derived from LIDAR data provided three-dimensional information of mangroves.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.3
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• pp.128-133
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• 1990

An equation is presented to calculate wave height due to shoaling, refraction and bottom friction. The equation in an integral form is evaluated by two different methods： A numerical method and an analytical method based on approximation. Both methods are used to calculate wave height and show very good agreement between their results. As shown in the figure of wave height variation vs. relative water depth, an increase of incident angle leads to a decrease in wave height. For the case of normal incident wave, the present equation can be reduced, under some assumptions, to the existing equation of Bretschneider and Reid (1954).

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.53-62
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• 2005

In this study, the thermal performance of multi-story double-skin facade(DSF) with variation of cavity height is evaluated to offer useful data in determining cavity height of multi-story DSF. For this, thermal criteria for multi-story DSF is adopted and a DSF model for evaluation of the thermal performance is established. Through the evaluation of CFD simulation, the recommended height of multi-story DSF is 5 stories or less to improve the thermal performance during the intermediate season.

• Journal of the Ergonomics Society of Korea
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• v.18 no.1
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• pp.91-108
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• 1999

In our previous work using a motion analyzer and 3-dimensional sonic digitizer, the arm shapes for 23 women in their early twenties were classified into three characteristic types. In order to design sleeves, suitable for arm movements for the three characteristic arm shapes, a relationship between arm length variation and shoulder/elbow angles has been investigated for four cases of arm movements (flexion, extension, adduction and abduction). Each arm movement can be characterized by the changes in shoulder angle and the changes in elbow angle at the maximal shoulder angle. In all the four cases of arm movements, the changes of shoulder length and cap height are largest at the maximal shoulder angle. These changes were little affected by changes in elbow angle. The changes in the lower arm length and the difference between cap height and upper arm length are the largest at the maximal elbow angle of the maximal shoulder angle. There is a linear relationship between cap height and shoulder angle during arm movements; thus, in designing sleeves the cap height can be determined from the regression of cap height vs. shoulder angle.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.425-427
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• 2006

It is quite difficult to transfer the National Height System 1985 to the island in China. In the study, one feasible and alternative way, which measures synchronally the tide variation at the island and the coast , is firstly introduced. Then, a new method is proposed. This new method combines GPS technique and Quasi-Geoid Determination technique (GQGD). It needs gravity data, GPS data, leveling data and DEM data, together with complex calculation method and the Earth gravity model. After describing the mathematical model and presenting the calculational steps, one experiment has been shown that this method is valid and can achieve accuracy up to 5 cm for the normal height, compared with the results both from the tidal observation and height approximation. Some suggestion is also given in the end.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.2 s.30
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• pp.155-165
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• 1989

The purpose of this study was to investigate on the sleeve form variation according to arm movements for elderly women. This study was experimented using the Plaster gypsum. The subjects who were elderly women were divided into three groups according to Rorher Index. Arm movements were five type ($0^{\circ},\;45^{\circ},\;90^{\circ},\;135^{\circ},\;180^{\circ}$) to each the vertical motion in front and in side. The statistical analyses used in this study were Mean, Standard Deviation, Spearman's correlation coefficients, paired T-test, Kruskal-wallis one-way ANOVA and Duncan's multiple range test. The results were as follows: 1) Increasing the movements, the width of the sleeve increased and the height of the sleeve cap decreased but girth of the sleeve cap was not consistant. 2) When varied the rates of the three aspects of the sleeve, the height of the sleeve cap showed the largest variation rate. 3) There was a negative correlation between the height and the width of the sleeve. On the other hand, there was a positive correlation between the sleeve width and the sleeve girth. 4) There were the vertical motion differences between in front and in side on the three aspects of sleeve. 5) The sleeve width and the sleeve girth were different according to somatotypes but the height of the sleeve cap was not different. 6) According to the variation rates of the body surfaces in length of standard lines, the form of sleeve was changed more in the front than in the back. Maximum variation rate showed in the areas of $D_1-D_3,\;E_1-E_3$ in the horizontal lines and $A-E_2$ in vertical lines. 7) According to the comparative drawing of the heights of sleeve cap and sleeve girth, the sleeve basic pattern $S_1(A.H/4)$ was more suitable for the direction $0^{\circ}\;and\;45^{\circ}$. And the basic pattern S_6(A.H/5)$ was more suitable for the direction $90^{\circ}$, the pattern $S_7(A.H/6)$ suitable for the direction $135^{\circ}$, and the pattern $S_8(A.H/8)$ was more suitable for the direction $180^{\circ}$.

• Structural Engineering and Mechanics
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• v.74 no.4
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• pp.533-545
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• 2020

An optimal design method for a spoke double-layer cable-net structure (SDLC) is proposed in this study. Simplified calculation models of the SDLC are put forward to reveal the static responses under vertical loads and wind loads. Next, based on an energy principle, the relationship among the initial prestress level, cross-sectional areas of the components, rise height, sag height, overall displacement, and relative deformation is proposed. Moreover, a calculation model of the Foshan Center SDLC is built and optimized. Given the limited loading cases, material properties of the components, and variation ranges of the rise height and sag height, the self-weight and initial prestress level of the entire structure can be obtained. Because the self-weight of the cables decreases with increasing of the rise height and sag height, while the self-weight of the inner strut increases, the total weight of the entire structure successively exhibits a sharp reduction, a gradual decrease, a slow increase, and a sharp increase during the optimization process. For the simplified model, the optimal design corresponds to the combination of rise height and sag height that results in an appropriate prestress level of the entire structure with the minimum total weight.

• Journal of ILASS-Korea
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• v.19 no.3
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• pp.136-141
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• 2014

This study reports numerically the characteristics of dust scattering around the coal storage pile yards, substantially affected by the windbreak wall height. The dust scattering is closely associated with the frictional effect of wind flows as well as the pressure variation that consequently affect the dust particle behavior. In the present study, with the use of the commercial code of FLUENT, the distribution of wind velocity and pressure are predicted around coal storage pile yard for four different heights of the wind break wall. From the results, it was found that for the case 1 with the outer windbreak wall height of 3 m and inner windbreak wall height of 6 m, the amount of scattering dust for a year was estimated to be 1451 kg, whereas for the case 4 where a height of outer windbreak wall is 10 m and a height of inner windbreak wall is 16 m, the amount of scattering dust for a year was 358 kg. It shows that the dust scattering can be reduced by 75%, indicating important role of windbreak wall height on particle scattering. The numerical results would be useful in decision of the appropriate height of windbreak wall for decreasing the amount of scattering dust under various environmental conditions.