• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.7
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• pp.620-628
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• 2005

The blinds in the intermediate space are installed to block the direct solar radiation. As the blind divide the airflow of intermediate space into two, thermal performance of Double-Skin Facade (DSF) are affected by the blind position. Therefore blind position should be planed with careful consideration in order to maximize the thermal performance of DSF. In this study, CFD was peformed to analyze the effect of blind position in multistory-type DSF in variation of other DSF elements. The simulation results showed that the case with narrow depth of intermediate space and outlet on upper side of outer-facade, it is profitable to place blind as close as possible to the outer-facade. In the other cases, the blind should maintain 0.15 m distance from outer-facade.

• International Journal of Air-Conditioning and Refrigeration
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• v.14 no.2
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• pp.57-65
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• 2006

The blinds in the intermediate space are installed to block the direct solar radiation. As the blind divides the airflow of intermediate space into two parts, thermal performance of Double-Skin Facade(DSF) is affected by the blind position. Therefore the blind position should be planned with careful consideration in order to maximize the thermal performance of DSF. In this study, CFD was performed to analyze the effect of blind position in multistory-type DSF in variation of other DSF elements. The simulation results showed that the case with narrow depth of intermediate space and outlet on upper side of outer-facade, it is profitable to place blind as close as possible to the outer facade. In the other cases, the blind should maintain 0.15m distance from outer facade.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.11 no.2
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• pp.1-6
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• 2015

The horizontal earth-to-air heat exchanger (HEAHES) thermal performance is excellent on cooling and heating season in hot arid regions was reported. But the HEAHES thermal performance results is difficult to find on intermediate season. This paper was performed full scaled experiment to investigate HEAHES thermal performance on intermediate season (Oct. 10th ~ 12th Nov. 12th). When the air entering to HEAHES is the lowest $2.3^{\circ}C$, outlet air temperature from HEAHES is $15.95^{\circ}C$ through PVC pipe that buried length 60m and depth 3m. When the air entering to HEAHES is the highest $24.8^{\circ}C$, outlet air temperature from HEAHES is $22.05^{\circ}C$. During intermediate season, the HEAHES COP is 2.71 in daytime and 6.53 in evening.

• The Journal of Engineering Geology
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• v.15 no.4 s.42
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• pp.391-405
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• 2005

Chemical and isotopic analysis for stream water, shallow groundwater, intermediate groundwater and deep groundwater was carried out to grasp hydrogeochemical characteristics of groundwater in the Heunghae area, Pohang city. Water type of stream water and shallow groundwaters is typified as Ca-Cl type, intermediate groundwater is $Na-HCO_3$, and deep groundwater is prominent in Wa-Cl type. $HCO_3^-\;and\;SiO_2$ in shallow groundwater are originated from weathering of silicate minerals, whereas those of deep groundwaters are resulted from weathering of carbonate minerals. Ca and Mg ions in both shallow and deep groundwaters are resulted from weathering of calcite and dolomite. $SO_4^{2-}$ in shallow groundwater is originated mainly from pyrite oxidation. As well depth increases, pH and TDS increase, but Eh and DO decrease. Alkali metal contents(K, Na, Li) increases as well depth increases, but alkali earth metal(Mg, Ca) and hi concentrations increase as well depth decreases. Anions, halogen elements(F, Cl, Br), and $HCO_3$ contents increase as well depth increases. The average stable isotope value of the groundwater of each depth is as follows; deep groundwater: ${\delta}^{18}O=-10.1\%o,\;{\delta}D=-65.8\%_{\circ}$, intermediate groundwater: ${\delta}^{18}O=-8.9\%_{\circ},\;{\delta}D=-59.6\%_{\circ}$, shallow groungwater : ${\delta}^{18}O=-8.0\%_{\circ},\;{\delta}D=-53.6\%_{\circ}$, surface water : ${\delta}^{18}O=-7.9\%_{\circ},\;{\delta}D=-53.3\%_{\circ}$ respectively.

• Journal of Mechanical Science and Technology
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• v.14 no.11
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• pp.1276-1285
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• 2000

The solubility, the surface concentration and the dissolution behavior of carbon dioxide in deep sea were numerically investigated. Base on the calculations the relations between the surface concentration of liquid carbon dioxide droplet with the hydrate film and the solubility and those between the ambient carbon dioxide concentration in the plume and the dissolution rate were obtained. The result show that a carbon dioxide droplet is released both at 1000 m in depth with the initial droplet diameter of 0.011 m or less and at 1500 m in depth with a diameter of 0.015 m or less, and the droplet is completely dissolved below 500 m in depth. The hydrate film acts as a resistant layer for the dissolution of liquid carbon dioxide, and the effect of the hydrate film on the dissolution of liquid carbon dioxide depended upon the depth.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.455-459
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• 1997

A methodology which supports the feature used from design to manufacturing for sculptured pocket is newly devlored and present. The information contents in a feature can be easily conveyed from one application to another in the manufacturing domain. However, the feature generated in one application may not be directly suitable for another whitout being modified with more information. Theobjective of the paper is to parsent the methodology of decomposing a bulky feature of sculptured pocket to be removed into compact features to be efficiently machined. In particular, the paper focuses on the two task: 1) to segment horizontally a bulky feature into intermediate features by determining the adequate depth of cut and cutter size and to generate the temporal precedence graph of the intermediate features and 2)to further decompose each intermediate feature vertical into smaller manufacturing features and to apply the variable feed rate to each small feature. The proposed method will provid better efficiency in machining time and cost than the classical method which uses a long string of NC codes necessary to remove a bulky fecture.

• Environmental Analysis Health and Toxicology
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• v.22 no.2 s.57
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• pp.129-135
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• 2007

Polycyclic aromatic hydrocarbons(PAHs) have been analyzed to assess vertical distribution of them with different land uses. The soils were collected from three layers; surface $(0{\sim}5cm)$, intermediate $(6{\sim}10cm)$, and deep $(11{\sim}15cm)$ layer, respectively considering land use; paddy, upland, and mountain in each site. Total 89 samples of soil from 10 sites were analyzed. Overall mean of ${\sum}PAHs$ were 137 (range $8.87{\sim}625{\mu}g\;kg^{-1}$), 203 (range $16.5{\sim}645{\mu}g\;kg^{-1}$), and $83.4{\mu}g\;kg^{-1}$ (range $6.65{\sim}667{\mu}g\;kg^{-1}$) for paddy, upland, and mountain soil, respectively. The dominant PAHs were fluoroanthene/benzo(b)fluoroanthene>pyrene>indeno(1, 2, 3-cd) pyrene in paddy, fluoroanthene/pyrene>benzo(b)fluoroanthene>chrysene in upland, and benzo(b)fluoroanthene>pyrene>chrysene in mountain soil, whereas the profile was quite similar for each other except that indeno(1, 2, 3-cd)pyrene and benzo(ghi)perylene are relatively higher in the paddy soils. Although the concentration gradient by depth was not observed in the paddy and upland soils because perturbation of soil layer by tillage, significant decrease was in the deep layer relative to the surface and intermediate layer. However, the concentration gradient of PAHs by soil depth was clearly shown in mountain soil without experiencing disturbance of tillage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1447-1454
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• 2013

In this study, we developed the equation of ship wave crests in intermediate as well as deep waters by extending Kelvin's (1887) theory using the recursive relation for the dispersion relation. The present equation can be applied for varying water depth as well as constant water depth. Using FLOW-3D we conducted numerical experiments to verify analytical prediction. The ship wave crest patterns became asymmetric on a plane slope when the ship propagates alongshore direction. That is, in shallower side, wave crests tend to be parallel to the coastline due to refraction and, in deeper side, wave crests tend to be orthogonal due to reverse refraction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.12B
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• pp.1475-1482
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• 2009

In ZigBee network, using energy efficiently is necessary because ZigBee node works by battery. To use energy efficiently, it is one of the way to reduce unnecessary network traffic. In this paper, it presents efficient shortcut routing algorithm using depth of destination node in ZigBee network. In traditional tree routing, each node transfers data only to its own parent or child node, which is inefficient way. Efficient shortcut routing algorithm is also based on tree routing. However, we suggests the algorithm with using neighbor table and depth of destination that is able to transfer data to other neighbor node, not only to parent or child node. It minimizes coordinator bottleneck state and unnecessary intermediate routing path which happens in traditional tree routing.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.9
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• pp.718-726
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• 2003

Carbon dioxide ocean disposal is one of the promising options to reduce carbon dioxide concentration in the atmosphere because the ocean has vast capacity for carbon dioxide sequestration. However, the dissolution rate of liquid carbon dioxide in seawater must be known in advance in order to estimate the amount of carbon dioxide sequestration in the ocean. Therefore, in the present study, calculations of the solubility, the surface concentration and the dissolution behavior of carbon dioxide when liquid carbon dioxide is released at 1,000m and 1,500m in depth are peformed. The results show that the droplet is completely dissolved below 500 m in depth if the carbon dioxide droplet is released both at 1,000m in depth with the initial droplet diameter of 0.011m or less and at 1,500m in depth with the diameter of 0.016 or less. Also, the surface concentration of carbon dioxide droplet with the hydrate film is about 50% of carbon dioxide solubility at 1,500 m in depth and about 60% of carbon dioxide solubility at 1,000 m in depth.