• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제29권7호
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• pp.477-483
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• 2018

A transparent antenna designed on the front glass of an automobile operating in the FM broadcast band(88~108 MHz) is proposed. A transparent antenna designed on the front glass of the automobile to avoid space limitation is typically positioned as a roof-mounted shark-fin antenna. An antenna designed on the front glass can reasonably solve the problems of low reception sensitivity and radiated interference from antennas for other service bands. The front glass has a unique closed-line structure, and this structure causes the surface current to flow to the front glass's surroundings; thus, the first resonance is caused before the broadcast band. Through the use of this closed-line structure, the surface current distribution is controlled, and an antenna for which the first resonance is operating in the frequency-modulated(FM) band can be designed. Moreover, the use of a micro-metal-mesh film that is a transparent electrode, suitable for designing a radio frequency device, enables the antenna to minimize visual perception through its transparency. The measured reflection coefficient($S_{11}$) of the antenna is less than -6 dB, and the average peak gain is -0.9 dB in the FM band. Experiments show that the transparent antenna on the front glass offers both the space and design freedom required to develop future automotive antennas.

• Journal of Bio-Environment Control
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• 제22권3호
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• pp.270-278
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• 2013

The objective of the present study is to provide data needed to decide covering method to be able to increase the thermal insulation and light transmittance efficiency of commercial greenhouse. The thermal insulation effect, PPF transmittance and quantity of condensation water were estimated in experimental tomato greenhouses covered with three types of coverings of single layer, air inflated and conventional double layers covering. The overall heat flow of air inflated double layers greenhouse was similar to that of conventional double layers greenhouse, but the temperature between covering material and thermal screen in air inflated double layers greenhouse was lower than that in conventional double layers greenhouse at the same outside temperature condition due to air leakage through the gap of roof vent. The overall heat transfer coefficients acquired by experiment that was performed in single layer and conventional double layers greenhouses were close to those obtained from model experiment. Even though the PPF transmittance of air inflated double layers greenhouse was lower than that of single layer greenhouse, which was greater than that of conventional double layers greenhouse. The quantity of condensation water on covering surface of single layer greenhouse was greater than that of air inflated double layers greenhouse due to lower covering surface temperature.

• Geomechanics and Engineering
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• 제12권4호
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• pp.657-673
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• 2017

Preventing water seepage and inrush into mines where close multiple-seam longwall mining is practiced is a challenging issue in the coal-rich Ordos region, China. To better protect surface (or ground) water and safely extract coal from seams beneath an aquifer, it is necessary to determine the height of the mining-induced fractured zone in the overburden strata. In situ investigations were carried out in panels 20107 (seam No. $2-2^{upper}$) and 20307 (seam No. $2-2^{middle}$) in the Gaojialiang colliery, Shendong Coalfield, China. Longwall mining-induced strata movement and overburden failure were monitored in boreholes using digital panoramic imaging and a deep hole multi-position extensometer. Our results indicate that after mining of the 20107 working face, the overburden of the failure zone can be divided into seven rock groups. The first group lies above the immediate roof (12.9 m above the top of the coal seam), and falls into the gob after the mining. The strata of the second group to the fifth group form the fractured zone (12.9-102.04 m above the coal seam) and the continuous deformation zone extends from the fifth group to the ground surface. After mining Panel 20307, a gap forms between the fifth rock group and the continuous deformation zone, widening rapidly. Then, the lower portion of the continuous deformation zone cracks and collapses into the fractured zone, extending the height of the failure zone to 87.1 m. Based on field data, a statistical formula for predicting the maximum height of overburden failure induced by close multiple seam mining is presented.

• 한국문화재보존과학회:학술대회논문집
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• 한국문화재보존과학회 2004년도 제20회 발표논문집
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• pp.15-24
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• 2004

The Seokgatap pagoda composed of mainly alkali granite and other minor pink-feldspar granite, fine-grained granite, granodiorite, diorite, gabbro, and tuff. Despite the small loss and damage derived from joints, its peel-off and exfoliation are serious enough to cause the heavy deterioration on the stone surface. The chemical and petrological weathering has partly replaced the original rock-forming minerals with clay minerals and iron oxyhydroxides. Based on the petrogenesis, rock materials of the pagoda is very similar to rocks of Dabotap pagoda and the Namsan granite in the Gyeongju. The central fart of the pagoda has sunken highly, which caused all the corners to split and the structural transformation to become worse. The reverse V-shaped gaps between the materials have broken stones filled in a coarse way. The iron plates inserted between the upper flat stone laid on other stones and tile pagoda body in the north and east side has been exposed in the air and corroded, discoloring of the adjacent stones. The overall diagnosis of the Seokgatap pagoda is the deteriorated functions of the stone materials, which calls for a long-term monitoring and plans to reinforce the stone surfaces. But the main body including the pagoda roof stone needs washing on a regular basis, and the many different cracks should be fixed with glue by using the fillers or hardeners designed for stone cultural properties after removing the cement mortar. In case of the replacement of the stone materials with new stones, it's necessary to examine the pagoda for the center of gravity and support intensity of the materials. The structural stability of the pagoda can be attained by taking a reinforce measure in geotechnical engineering and making a drainage. The ground humidity, which has aggravated weathering and structural instability, should be resolved by setting up a humidity reduction facility. The contamination of lichens and bryophyte around the pagoda and on the surface is serious. Thus biochemical treatments should be given too in order to prevent further biological damages and remove the vegetation growing on the discontinuous planes.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• 제37권3호
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• pp.143-156
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• 2019

The purpose of this study is to examine whether the Sinseo Innovation City of Daegu has been eco-friendly developed by analyzing changes in NDVI (Normalized Difference Vegetation Index) and LST (Land Surface Temperature) and conducting field surveys. Using Landsat satellite images, it compares NDVI and LST changes between the years of 2008 and 2018. The results of the study are as follows. First, the NDVI has decreased by 0.07 and the zLST has increased by $0.85^{\circ}C$ over the past 10 years. Second, districts with lower NDVI and higher zLST were concentrated with infrastructure with impermeable materials. Districts with higher NDVI and lower zLST were utilized urban design techniques such as permeable parking lot, green roof, and permeable pavement. Third, districts with higher NDVI and lower zLST were applied eco-friendly planning items properly by district unit plan guideline. It is meaningful to suggest planing directions and urban planning elements considering the environmental friendly development.

• Economic and Environmental Geology
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• 제37권5호
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• pp.569-583
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• 2004

The rock properties of the West pagoda in the Gameunsaji temple site are composed mainly of dark grey porphyritic granodiorite with medium grained equigranular texture and developed with small numerous dioritic xenoliths. These xenoliths occurred with small holes due to different weathering processes. As a weathering results, the rock properties of this pagoda occur wholly softened to physical hardness because of a complex result of petrological, meteorological and biological causes. Southeastern part of the pagoda deteriorated seriously that the surface of rock blocks showed partially exfoliations, fractures, open cavities in course of granular decomposition of minerals, sea water spray and crystallization of salt from the eastern coast. The Joint between blocks has small or large fracture cross each other, contaminated and corrupted for inserting with concrete, cement mortar, rock fragments and iron plates, and partially accelerated coloration and fractures. There are serious contamination materials of algae, fungus, lichen and bryophytes on the margin and the surface on the roof stone of the pagoda, so it'll require conservation treatment biochemically for releasing vegetation inhabiting on the surface and the discontinuous plane of the blocks because of adding the weathering activity of stones and growing weeds naturally by soil processing on the fissure zone. Consisting rock for the conservation and restoration of the pagoda would be careful choice of new rock properties and epoxy to reinforce for the deterioration surfaces. For the attenuation of secondary contamination and surface humidity, the possible conservation treatments are needed.

• Journal of Animal Environmental Science
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• 제1권1호
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• pp.9-19
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• 1995

This study was carried out to investigate the effect of sawdust bedding barn on manure handing, management labour and physiological aspect of dairy cows, and then to establish the criteria on the optimum utilization method of sawdust bedding barn. 46 tie stall barns and 49 sawdust bedding barns were surveyed to cmopare the milk productivity between two different barns, and also 5 tie stall barns, 15 sawdust bedding barns and 1 rice hull bedding barn were selected to study the utilization situation of sawdust barn in Kyung-Ki province area. The major results obtained were as follows; 1. The roof material of sawdust barn were consisted of 66% vinyl house, 23% PVC light and 11% slate and galvanum coated tin. Most of the floor structure was earth ground with the rate of the approximately 82%. 2. The average occupied area of sawdust bed per cow was 15.2 $m^2$, depth that 30 cm and the utilization period was 12 months. 3. Milk Yield was significantly higher at sawdust barn than at tie stall barn(P<0.01). Bacterial and somatic cell count in raw milk were less at the sawdust barn than in tie stall barn. However, there was not significance difference between two barns. 4. The labour hour needed to cow management in the sawdust barn was approximately 48% of that of tie stall barn. 5. The temperature and moisture content measured in sawdust bed were closely affected by seasonal ambient temperature. The skin and hair of cow were much cleaner at the PVC light roofed sawdust barn than any other roof materials. 6. The additives used for improving of fermentation did not show any effect on temperature and moisture content in sawdust bed. When the ambient temperature was $30.4^{\circ}C$, the surface temperature of measured 1 cm above the sawdust bed was $12.2^{\circ}C$ lower and the temperature of 100 cm above the sawdust bed was $2.4^{\circ}C lower under shading net facility than that of vinyl roofed one.7. The hoof length of miking cow was 7.95 cm in tie stall and 9.19 cm in sawdust barn with high significance (P<0.01). And disease occurence such as mastitis and foot-rot tended to decrease in the sawdust barn. 8. The number of total bacteria and coliform bacteria were less in the sawdust bed compared with earth ground resting area. And a parasite strongyloides papillosus was detected but without any infected cow. 9. The nitrate($NO_3N$) content in non-roofed earth ground resting area and earth ground under the sawdust bed was likely to pollute the ground water. 10. In economic point of view, rice hull bedding barn was the cheapest among different systems. And in the sawdust bedding barn PVC light + slate roofed barn was most desirable, and vinyl roofed one the least.

• Journal of the Korean Institute of Landscape Architecture
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• 제41권6호
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• pp.107-116
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• 2013

This study was undertaken to investigate the characteristics of retention and evapotranspiration in the extensive greening module of sloped and flat rooftops for stormwater management and urban heat island mitigation. A series of 100mm depth's weighing lysimeters planted with Sedum kamtschaticum. were constructed on a 50% slope facing four orientations(north, east, south and west) and a flat rooftop. Thereafter the retention and evapotranspiration from the greening module and the surface temperature of nongreening and greening rooftop were recorded beginning in September 2012 for a period of 1 year. The characteristics of retention and evapotranspiration in the greening module were as follows. The water storage of the sloped and flat greening modules increased to 8.7~28.4mm and 10.6~31.8mm after rainfall except in the winter season, in which it decreased to 3.3mm and 3.9mm in the longer dry period. The maximum stormwater retention of the sloped and flat greening modules was 22.2mm and 23.1mm except in the winter season. Fitted stormwater retention function was [Stormwater Retention Ratio(%)=-18.42 ln(Precipitation)+107.9, $R^2$=0.80] for sloped greening modules, and that was [Stormwater Retention Ratio(%)=-22.64 ln(X)+130.8, $R^2$=0.81] for flat greening modules. The daily evapotranspiration(mm/day) from the greening modules after rainfall decreased rapidly with a power function type in summer, and with a log function type in spring and autumn. The daily evapotranspiration(mm/day) from the greening modules after rainfall was greater in summer > spring > autumn > winter by season. This may be due to the differences in water storage, solar radiation and air temperature. The daily evapotranspiration from the greening modules decreased rapidly from 2~7mm/day to less than 1mm/day for 3~5 days after rainfall, and that decreased slowly after 3~5 days. This indicates that Sedum kamtschaticum used water rapidly when it was available and conserved water when it was not. The albedo of the concrete rooftop and greening rooftop was 0.151 and 0.137 in summer, and 0.165 and 0.165 in winter respectively. The albedo of the concrete rooftop and greening rooftop was similar. The effect of the daily mean and highest surface temperature decrease by greening during the summer season showed $1.6{\sim}13.8^{\circ}C$(mean $9.7^{\circ}C$) and $6.2{\sim}17.6^{\circ}C$(mean $11.2^{\circ}C$). The difference of the daily mean and highest surface temperature between the greening rooftop and concrete rooftop during the winter season were small, measuring $-2.4{\sim}1.3^{\circ}C$(mean $-0.4^{\circ}C$) and $-4.2{\sim}2.6^{\circ}C$(mean $0.0^{\circ}C$). The difference in the highest daily surface temperature between the greening rooftop and concrete rooftop during the summer season increased with an evapotranspiration rate increase by a linear function type. The fitted function of the highest daily surface temperature decrease was [Temperature Decrease($^{\circ}C$)=$1.4361{\times}$(Evapotranspiration rate(mm/day))+8.83, $R^2$=0.59]. The decrease of the surface temperature by greening in the longer dry period was due to sun protection by the sedum canopy. The results of this study indicate that the extensive rooftop greening will assist in managing stormwater runoff and urban heat island through retention and evapotranspiration. Sedum kamtschaticum would be the ideal plant for a non-irrigated extensive green roof. The shading effects of Sedum kamtschaticum would be important as well as the evapotranspiration effects of that for the long-term mitigation effects of an urban heat island.

• Journal of the Korean Wood Science and Technology
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• 제36권1호
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• pp.79-87
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• 2008

Many researchers have studied on rooftop greening that can be installed in abandoned spaces on a building roof. The most important issue in rooftop greening is the soil weight problem. The light greening materials are needed to solve this problem. Therefore, many alternative materials against the soil were investigated for rooftop greening. In this study, the waste wood chips and the waste paper slurry were evaluated as the lightweight vegetation foundation for rooftop greening. It also has a meaning for recycling of waste materials. The mixture ratio of waste wood chips to waste paper slurry for the board (the foundation of greening) was 60 to 40. The wet strength resin and the sizing agent were additionally added with different amount. After the forming of the board, physical and chemical properties were tested with the variation of wet strength resin and sizing agent. As the result of the test, the board with 15% of wet strength resin in the wet condition showed the highest strength. Futhermore, the moisture evaporation loss from the board surface with sizing agent was much lower than that from the board without sizing agent. Therefore, it was clear that the sizing agent was effective for water retention. The change of thickness in the wet condition was less than 1 mm, and it showed that the board is the predominant material on the dimensional stability. The average pH value of the board was ranged from 7.6 to 8.25.

• Journal of Wetlands Research
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• 제18권4호
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• pp.342-349
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• 2016

Andong belongs to the Nakdong River Basin, Nakdong River is flowing through the city, including Andong dam and Imha dam. The runoff due to provincial transfer and impervious area has been increasing by urbanization increases and nonpoint source loads. In this study, we evaluate the runoff and nonpoint pollution loads in accordance with the development targeted at selected urban water cycle leading to Andong city. Andong city leading to the water cycle plan to evaluate the directly runoff and BOD, T-N and T-P nonpoint pollutant loads using the CN into account the temporal and spatial changes. Evaluation, direct runoff per year is 10.41 % if the green roof and a water permeable pavement replacement, water cycle parks and streets compositions, City impermeable layer improvements to be business including four kinds of scenario is applied to both the development and the BOD non-point pollutant loads 20.56%, T-N 9.55% and T-P pollution and nonpoint loads was investigated to be reduced 14.29%. Four kinds of low lapse rate of the development scenario of the highest thing urban impervious surface was investigated by improving business development prior year annual direct runoff is 6.25 %, BOD nonpoint pollution loads are 11.84%, T-N nonpoint pollution loads are 4.46 % and T-P was investigated by reducing pollutant loads to be 10.20%.