• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.870-873
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• 2014

Green roof systems has widely been used on rooftop of buildings by considering environmental benefits in aspects of bio-diversity, storm-water runoff as well as noise reduction. To predict noise reduction effect by green roof systems, it is necessary to measure in-situ acoustical properties of the components by devices enabling in-situ measurements. In this study, Micro-flown, which is the state of the arts device to measure in-situ normalized impedance and absorption coefficient has been used to measure acoustical properties of green roof materials according to different water saturation condition in the materials.

• 국제초고층학회논문집
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• 제3권4호
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• pp.273-278
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• 2014

Green roof's performance in reducing stormwater runoff has been reported by numerous studies. Nonetheless, the roles of low growing vegetation in influencing stormwater runoff reduction on green roofs have been greatly overlooked. This paper describes an experiment investigating the influence of low growing vegetation in the reduction of tropical stormwater runoff on extensive green roofs. Three types of locally occurring native vegetation and one non-native Sedum species were selected (fern, herb, grass and succulent) for the experiment. Stormwater runoff reduction performance from different low growing species was done by measuring excess water runoff from the simulated green roof modules. The results show significant differences in stormwater runoff reduction from different types of vegetation. Fern was the most effective in reducing stormwater runoff, followed by herb, Sedum and grass. Vegetative characters that are found to attribute towards the performance of stormwater runoff are rooting density, structure, density, leaf type, and vegetation biomass.

• Environmental Engineering Research
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• 제17권3호
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• pp.151-156
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• 2012

This research described the magnetic method for the rapid removal of green algae in water. We modified the pH, cation concentration, and magnetic powder concentration to discover the best removal performance. In order to rapidly remove green algae from water, we added magnetic powder and chitosan into algae water to make a magnetic substance and this was extracted by a strong neodymium magnet. The optimized conditions were pH of 6.5-7.5, chitosan concentration of 10 mg/L, and magnetite powder concentration of less than 0.05%. A higher removing rate was observed when a higher amount of magnetite or chitosan was used, but the total amounts of phosphorus or nitrogen were not decreased.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2557-2560
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• 2010

To assay for antioxidant capacity of natural products considered important in producing human health benefits, a practical and economical method using pellet techniques was developed. A standard visualizing reagent, 1,1diphenyl-2-picryl-hydrazyl (DPPH), was mixed with a water-miscible polyvinyl alcohol (PVA), serving as a solid phase support for the DPPH reagent. A DPPH pellet was prepared by dropping a small volume of the DPPH solution onto PET film, and drying in an oven. The PVA-based DPPH pellet was dissolved into water, in which the water-miscible PVA plays as a non-ionic surfactant to help the DPPH reagent to be dissolved into the solvent. Using the DPPH assay, the antioxidant capacity of water-soluble extracts of black soybean, barley, green tea, and green gram was examined. Among the natural products tested, green tea showed the highest antioxidant capacity. This PVA-based DPPH antioxidant assay can be further applied in the natural food, raw plant material, and health product inspection field.

• Journal of the Korean Wood Science and Technology
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• 제43권5호
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• pp.691-699
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• 2015

To evaluate the possibility of charcoal as Green Infrastructure (GI) materials, data such as moisture content, amount of adsorbed water, and amount of evaporation were collected. Some data from previous study were referenced to find out if correlations exist between results in this study and previous study. Only porosity was directly related to moisture content. Two mechanical charcoal had better abilities than traditional charcoal in all three categories. Mechanical black charcoal chips produced by National Forestry Cooperative Federation (NFCFC) adsorbed 333.3% of water in thirty minutes, 297.5% in five minutes, and evaporated around 75% water in four days. This ability is much higher than other five charcoal. Even though results of test showed various degrees and NFCFC was the best as GI materials, data of charcoal were also within acceptable range based on generally accepted characteristics of GI materials.

• 설비공학논문집
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• 제21권12호
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• pp.678-687
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• 2009

The purpose of this study is to develop the assessment category, items, a detail standard for environmentally friendly evaluation on the school. and to analyze the plan to improve the level of certification criteria on the School's water resource and environmental pollution. The results of this study brings on promoted environmentally friendly appreciation, resource con servation, reduction of contaminant, accordance in and around building, etc. For this purpose, analysis of domestic and foreign environmental friendly architectural citation screening system-BREEAM (1991), LEED 2.0(2001) etc.-was preceded, and through interview, survey and forum with professional group, developed evaluation item was verified and reappraised. Developed evaluation item were composed of 40 schools about water resource and environmental pollution.

• 통합자연과학논문집
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• 제14권1호
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• pp.6-10
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• 2021

New materials are very useful due to their wide range of applications, however, they also have caused new pollutants that damage our environment. Chemists have been conscious of the severity of these environmental problems and a great deal of effort has been put into developing environmentally benign chemical processes to synthesize new materials (green synthesis). We also have reported a green synthesis method of synthesizing silver nanoparticles using water-glycerol solution in a previous study. While conducting further research, we have recently discovered that the size of silver nanoparticles is proportional to the quantity of water present in glycerol. This method is completely benign and ecofriendly pathway, as the size of silver nanoparticles is adjusted solely by controlling the quantity of water added to glycerol, without extra additives and energy.

• 한국식품영양과학회지
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• 제36권8호
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• pp.1043-1047
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• 2007

시판되고 있는 녹차잎을 $75^{\circ}C$에서 알칼리 이온수로 10분간 추출하여 녹차를 제조한 뒤, 물리화학적 특성을 분석하였다. 알칼리 이온수로 제조한 녹차의 총 페놀 함량, 총 플라바놀 함량과 아스코르브산 함량은 pH가 증가할수록 감소하는 경향을 보였다. Hunter 색도 L, a, b값은 pH 증가에 따라 각각 감소, 감소, 증가하는 경향을 나타내었다. 녹차의 주된 성분인 epicatechin류의 함량은 pH가 증가할수록 감소하였고, 카페인은 유의차를 나타내지 않았다. DPPH 라디칼 소거능도 pH가 증가할수록 감소하였으며, tyrosinase 억제능은 pH 8.85의 알칼리 이온수 녹차에서 가장 높게 측정되었다.

• 한국환경복원기술학회지
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• 제6권1호
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• pp.28-33
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• 2003

In this study, we observed air temperature to make clear that land coverage condition and stand form has a certain relationship to air temperature during the night in various green space. And with revolution analysis, we interpreted relationship of air temperature distribution in the green space, The way of analysis is this land coverage rate and air temperature, of number of tree volume of tree air temperature. With this experimental result, we can propose green plan, which is taking into consideration lower effect of air temperature. In this result, lower zone is formed in forest and water area, higher zone is formed in paved surface and barren ground. but this gap is a little. arbor+subarbor area, in the point of water area surrounded stand is formed relative lower air temperature. As a result to make up efficiency lower air temperature area, it is needed to make water area which has surrounded forest, and it is needed to make stand form lower air temperature 2~3 layer forest. In order of arbor, subarbor, shrub, the lower air temperature is more effect.

• 한국해양공학회지
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• 제16권3호
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• pp.19-27
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• 2002

The motion of a floating OWC chamber in waves is studied taking account of fluctuating air pressure in the air chamber. An atmospheric pressure drop occurs across the upper opening of the chamber which causes not only hydrodynamic but also pneumatic added mass and damping forces to the floating chamber. A velocity potential in the water due to the free surface oscillating pressure patch is added to the conventional radiation-diffraction potential problem. the potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine Green function wile the outer problem with the Kelvin Green function. The two integral equations are solved simultaneously by making use of a matching boundary condition at the lower opening of the chamber to the outer water region. The chamber motion in the frequency domain is calculated for various values of parameters related to the atmospheric pressure drop. The present methods can also be sued for the analysis of air-cushion vehicle motion as well as for the design of a floating OWC wave energy absorber.