• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.451-456
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• 2012

This study was carried out to evaluate thermal performance of the renewable hybrid heat supply system with solar thermal system and wood pellet boiler for Zero Carbon Green home of apartment houses. The hybrid heat supply system was set up at Korea Institute Energy Research in 2011. The system was comprised of the wood pellet boiler unit with heat capacity designed as 20,000 kacal/hr, a evacuated tubular solar collector 3.74 $m^2$ of aperture area at the $20^{\circ}$ install angle, a 0.3 $m^3$ hot water storage tank, a 0.15 $m^3$ hot water storage tank for space heating. Thermal performance tests for one-house of apartment house were carried out by hot water load and heating load in winter season through the hybrid heat supply system. As a result, hot water energy supplied by the hybrid heat supply system was 11kWh in a day. Solar thermal energy portion was 2.99kWh which is 27% of the total hot water energy supply. wood pellet boiler supply portion was 8.017kWh which is 73% of the total hot water energy supply.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.4
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• pp.59-66
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• 2000

This study was carried out to investigated the water requirement of twisted sweet peppers which are cultivated in a green house. The meteorological conditions during the experiment period was close to that of normal year except the temperature and relative humidity. The growth status was improved with the increased saturation ratio. The range of the variation of daily water requirement were very large. The peak consumption occurred in the early August. And the higher saturation ratio resulted in higher water requirement. The total water requirement were about 57.180g/d/plant for pot with 100% (P100) of saturation , about 38.700g/d/plant for pot with 80%(P80) of saturation , about 23,720g/d/plant for pot with 60%(P60) of saturation, and about 53, 390g/d/plant for field cultivation in the green house, respectively. The water requirement was correlated with average ambient temperature and growing status, while no significant correlation were found between water requirement and minimum relative humidity or intensity of solar radiation. And the higher correlation was shown as the saturation ratio was increased. The transpiration coefficients of twisted sweet pepper were 378.0g/g for field cultivation in the green house, 363.3g/g for P100, 338.7g for P80 which was the smallest among pot cultivation , and 472.1g/g for P60 , respectively.

• Journal of Korean Society of Rural Planning
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• v.13 no.3
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• pp.51-60
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• 2007

In terms of the indicators by the type for the landscape plan per the district nit, geographic ecology indicators were the items such as water, water system, topography and climate, while biological ecology indicators were the items such as green zone size, green zone ratio, biotope size and distribution. The sensory and visual indicators were the items such as view point, view axis and skyline, and the accessibility indicator items for the green zone were applied as the socially used indicators. As for the application method according to each indicator, the water or water system was expressed and applied through the slopes and elevation topographic analysis drawings, the climate was expressed and applied through the main direction of the wind and the cold wind pass alley drawings. As for the green zone size and green zone ratio, the land use according to the status and housing area development was compared to present the measured figures. In case of the biotop size and the distribution item, the range was limited to the preparation of the biotope drawings for the focused preservation. As for the view point and view axis, the view point was selected according to the view point to prepare and apply the view analysis drawing in which the view area to be preserved is analyzed. As for the skyline, its landscape photo was composed with the housing area shape, and then skyline photography was applied as the plan in order to propose and consider the various shapes of the skyline. As for the accessibility to the peen zone, the network drawing was drawn to reflect the users' accessibility and continuity of the green zone formed and preserved according to the land use plan and then the drawing was prepared and proposed as the applicable plan.

• Advanced Composite Materials
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• v.16 no.4
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• pp.299-314
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• 2007

In the present study, natural fibers (jute, kenaf and henequen) reinforced thermoplastic (poly(lactic acid) and polypropylene) and thermosetting (unsaturated polyester) matrix composites were well fabricated by a compression molding technique using all chopped natural fibers of about 10 mm long, respectively. Prior to green composite fabrication, natural fiber bundles were surface-treated with tap water by static soaking and dynamic ultrasonication methods, respectively. The interfacial shear strength, flexural properties, and dynamic mechanical properties of each green composite system were investigated by means of single fiber microbonding test, 3-point flexural test, and dynamic mechanical analysis, respectively. The result indicated that the properties of the polymeric resins were significantly improved by incorporating the natural fibers into the resin matrix and also the properties of untreated green composites were further improved by the water treatment done to the natural fibers used. Also, the property improvement of natural fiber-reinforced green composites strongly depended on the treatment method. The interfacial and mechanical results agreed with each other.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.5
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• pp.57-67
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• 2019

Water-Birds are the birds that occupy the highest proportion in Korea, inland wetlands and reservoirs provide them with a good environment as habitat, but their habitats have been losing because of thoughtless development. Therefore, artificial plant islands in reservoirs are important for improving habitat environment and providing food resources. However, there are no research and standards on the built and management of artificial plant islands. So this study is to find out the density of bird using artificial plant island as habitat through monitoring using UAV focus on the Cheonho-reservoirs located in Seobuk-gu, Cheonan-si(Middle Chungcheong Province). Further, the correlation analysis with environmental factors was conducted to determine the effect of artificial plant islands as habitats for water-birds. The supervised classification of the three-time images taken by the drone identified 244 white-billed ducks and 46 mandarin ducks. The utilization rate was different for each photographed date, and more individuals were identified in wet artificial plant islands than dry ones. As a result of analyzing the utilization follow environmental factors, the distance from the trail showed a significant correlation, and the other factors did not have a statistically significant effect. This study is the first case of the UAV monitoring method of the water-birds using artificial plant islands in the reservoir, and can be used as the basic data for the built and management.

• Journal of the Korean Society of Food Culture
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• v.25 no.2
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• pp.232-239
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• 2010

This study was designed to investigate the effects of green tea extract on aluminum-induced damage to phospholipid content in old rat cerebral tissue. The aim of this study was to investigate the possibility that aluminum is the cause of Alzheimer's disease. Forty Sprague-Dawley old male rats weighing 350$\pm$10 g were divided into four groups, consisting of a control group (CON), 40 ppm aluminum sulfate group (Al-40), green tea water extract group (GTWE), and 40 ppm aluminum sulfate and green tea water extract groups (Al-40+GTWE) and kept on their respective diets for 12 weeks. In order to discover the influence of aluminum on cerebral tissue of old male rats, the serum aluminum concentration and phospholipid composition were compared between the aluminum-treated group and the normal group. The results showed that the serum aluminum concentration was higher in the aluminum sulfate-treated group than in the normal group. The cerebral tissue phospholipid concentration decreased significantly in the aluminum sulfate treated group as compared to the normal group. The results of this experiment show that increase of aluminum concentration in experimental animals causes the rise of serum aluminum and phospholipid concentrations, phenomena that are very similar to those shown in Alzheimer's disease., The results of this experiment, together with reports that aluminum is a cause of neurofibrillary tangles in cerebral tissue, therefore demonstrate the possibility that aluminum is the cause of Alzheimer's disease. Green tea water extract is also shown to be an effective therapeutic candidate for the treatment of Alzheimer's disease.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.535-546
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• 2011

The study area investigated in this research is Hwaseong city, Gyeonggi-Do where small scale development is currently in progress. For the last three years, we carried out the environmental and ecological assessment by using data from The Ministry of Environment and Han River Basin Environmental Office. Most of development works in Hwaseong city, Gyeonggi-Do are small scale developments which are related with factory and distribution complex based on individual laws and regulations. However, environmental and ecological assessment is not being sufficiently reflected beforehand. Especially, because the development takes place mainly in the outskirts of the city, the fine forest is continuously being damaged. We analyzed changes in green zone area caused by the developments. As a result, the percentage of original green zone was decreasing while the percentage of artificial green zone was increasing. We should maintain the percentage of the original green zone in order to conserve natural environment. In the past three years, the damage of the DGN (Degree of Green Naturality) 7 area that has high conservative value was little, but, there was serious damage in the area of DGN 6. In order to conserve natural environment, political and institutional investigation should be seriously carried out for mitigation of environmental and ecological damages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.342-347
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• 1999

The objectives of this study were to investigate biological activities such as nitrite scavenging effect of water and methanol fractions obtained from each green juice(Angelica keiskei, kale, carrot) under different pH conditions, and antioxidant vitamin contents in green juice made of green yellow vegetables. The result shows that nitrite scavenging effect of each green juice was 14.0~91.2% in model system. The methanol fraction provided higher effect than the water fraction. The nitrite degradation was the highest at pH 1.2. Nitrite scavenging effect of methanol fraction obtained from kale juice was 91.2% at pH 1.2 which was the highest among tested samples in this experiments. Consequently, extracts of kale juice were shown to provide the greatest functional properties among the vegetables tested. Contents of vitamine E and C in the extracts of kale were higher than the others.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.4
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• pp.475-491
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• 2012

Green Chemistry emerged at the end of 20th century, which aims the development of the technologies for the sustainable society at the molecular level. Most products we consume in everyday life are produced through chemical processes, and we often oversee the fact that huge amount of solvents are used and disposed. At the present time most solvents used in laboratories as well as industries are volatile organic compounds(VOC), which gives health and environmental problems. Therefore scientists are seeking new materials which have equivalent properties of VOCs as solvent, and at the same time gives no health and environmental problems. In this brief review, the author describes the present status of research and development activities of green solvent materials throughout research societies worldwide. At present the most attractive green solvent candidates are water, glycerol, supercritical carbon dioxide and ionic liquids. In order to give the pictures of these materials, the author tried to introduce the overall aspects of green solvents in various chemical reaction as well as catalytic roles.

• Current Photovoltaic Research
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• v.9 no.1
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• pp.17-21
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• 2021

In this study, the effect of water level and temperature on the power generation was investigated in a water tank with an aquavoltaic PV module to perform feasibility research for the development of salt farm aquavoltaic system. The silicon solar cell attached to the bottom of each water tank is a 1-cell mini module, and the underwater effects of the crystal phase (19.0~19.9% of single- & 17.9~19.9% of poly-crystalline) of the PV module were investigated, and power generation characteristics for water level (0~10 cm) and temperature (10~40℃) were analyzed. The deterioration coefficients according to the water level and temperature of each single- and poly-crystalline module were investigated at very similar levels such as, -2.01 %/cm and -2.02 %/cm, -0.50 %/℃ and -0.48 %/℃, respectively. Therefore, in salt farm aquavoltaic system, water levels need to maintain as low as possible, and heat-induced degradation is similar to those shown in general land, and no factors have been found to be affected by the underwater environment depending on the determination.