• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.6 s.113
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• pp.90-97
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• 2006

The effects of a green buffer zone to protect a residential area from air pollution from industrial facilities and traffic was examined by analyzing the case of a green buffer zone in the Shiwha industrial complex. The green buffer zone is 175 m wide. The intent was to assess the dispersion patterns of atmospheric air pollutants and the reduction in concentration around the green buffer zone. To measure atmospheric sulfur dioxide$(SO_2)$ and nitrogen dioxide$(NO_2)$ concentration, badge-type passive samplers were used and set up at 76 locations in order to measure the concentration of air pollutants with respect to the spatial dispersion. The weighted mean values of $SO_2\;and\;NO_2$ concentration were $3\~57 ppb\;and\;18\~62 ppb$ and the differences among the green buffer zone, the industrial area and the residential areas were $0.7\~1.1 ppb$. Mean values of atmospheric concentrations of $NO_2$ were similar in industrial and, residential areas and the green buffer zone. Results of the study show that the effect of the green buffer zone on reducing the dispersion of air pollutants was very low. This study also recommends that micro-climate, i.e., wind direction should be considered as a factor for planning and design of green buffer zones.

• Korean Journal of Remote Sensing
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• v.28 no.6
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• pp.661-670
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• 2012

Urban forests provide great ecosystem services to population in metropolitan areas even though they occupy little green space in a huge gray landscape. Unfortunately, urbanization inherently results in threatening the green infrastructure, and the recent urbanization trends drew great attention of scientists and policy makers on how to preserve or restore green infrastructure in metropolitan area. For this reason, mapping the spatial distribution of the green infrastructure is important in urban environments since the resulting map helps us identify hot green spots and set up long term plan on how to preserve or restore green infrastructure in urban environments. As a preliminary step for mapping green infrastructure utilizing multi-source remote sensing data in urban environments, the objective of this study is to map vegetation volume by fusing LiDAR and multispectral data in urban environments. Multispectral imageries are used to identify the two dimensional distribution of green infrastructure, while LiDAR data are utilized to characterize the vertical structure of the identified green structure. Vegetation volume was calculated over the metropolitan Chicago city area, and the vegetation volume was summarized over 16 NLCD classes. The experimental results indicated that vegetation volume varies greatly even in the same land cover class, and traditional land cover map based above ground biomass estimation approach may introduce bias in the estimation results.

• Journal of Environmental Science International
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• v.19 no.1
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• pp.47-59
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• 2010

This study was to examine the characteristics of wirdbirds habitat for improvement plan in green corridor. The target site, Gangseo-gu artificial green corridor was set up with the structure in which small scale of core green space with Goongsan and Yeomchang neighborhood parks in urbanized city was connected with the artificial green space with Gongamnaru, Hwanggeumnae neighborhood parks with 28~42.5 m in width. Wild birds six~eleven species; Dendrocopos spp, Paradoxornis webbiana, Parus major, Phasianus colchicus, etc. were observed in core green, but wild birds of two~five species: Columba livuia, Passer montanus, Pica pica, Hypsipetes amaurotis, etc. were observed in artificial green space. Thus wild birds of artificial and generalist species only moved in artificial green space. The artificial green space where vegetation structure was consisted of single-layer with poorness chose target species laying stress on generalist species and edge species of Parus major, P. palustris, Paradoxornis webbiana etc. for short-term and interior species of Dendrocopos major, Picus canus, etc. for long-term. The result suggested enhancement methods for target species's habitat in green corridor: to secure at least a corridor 30 meters in artificial corridor, to secure ecological pond, to offer the various shelterer and environment of prey-resources through the multi-layer structure.

• Journal of the Korean Institute of Rural Architecture
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• v.1 no.1
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• pp.87-96
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• 1999

The purpose of this study is to suggest a model of planning of urban on focused Seonhwan-up in Chongan-city. The subject matter of this paper is urban design of small town which has factors of ecological conditions in rural area. We can check ecological design factors of this city through green and water space, first of all. If they are produced by biotope network, this city in the nature is to create eco-city which has symbiosis between human and a creature.

• Journal of agriculture & life science
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• v.43 no.3
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• pp.27-34
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• 2009

Green tea was prepared by soaking 1.5 g of green tea leaves into 100 mL of distilled water at $75^{\circ}C$ for 5 min. The green tea was stored at three different conditions - (A) green tea was stored at not-artificially excluding natural light condition, at natural air condition, and without addition of vitamin C; (B) green tea was stored at artificially excluding natural light condition by wrapping a vial with aluminium foil, at nitrogen filling up condition, and with addition of 30 mg/100 mL of vitamin C; and (C) green tea was stored at artificially excluding natural light condition by wrapping a vial with aluminium foil, at nitrogen filling up condition, and without addition of vitamin C. After 28 days of storage at $4^{\circ}C$, the chemical quality of the green tea was evaluated. Total phenolic contents of (A), (B), and (C) green tea decreased to 71.50, 73.88 and 75.07%, respectively, after storing for 28 days compared to those of beginning state. DPPH radical scavenging activities of (A), (B), and (C) green tea were 87.87, 92.93 and 88.39%, respectively. Epigallocatechin gallate (EGCG), the main active compounds of green tea, contents of (A), (B), and (C) green tea were 130.61, 136.47 and 4.34%, respectively. The results indicated that light, air condition, and vitamin C were significantly important to the chemical quality of green tea during storage.

• Environmental Mutagens and Carcinogens
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• v.25 no.2
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• pp.71-75
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• 2005

Green tea and their major constituents such as catechins are famous materials for their anti-oxidative and anti-carcinogenic activity, but many compounds with reducing power can promote the oxidation in their oxidized form or in the presence of metal ion. We investigated the pro-oxidative effect of the ethanol extract equivalent up to 30mg of dried weight of green tea leaves in four in vitro systems which could be used for detecting DNA damage. Although ethanol extract of green tea did not show significant mutagenicity in Salmonella typhimurium TA102, which is sensitive strain to oxidative stress, it degraded deoxyribose extensively in the presence of $FeCl_3-EDTA$ complex, promoted 8-oxoguanine formation in the live bacteria cell, Salmonella typhimurium TAI04, and cleaved super coiled DNA strand with the help of copper ion. It suggested that green tea, famous anti-oxidative material, can be pro-oxidant according to the condition of extraction or metal existence.

• Current Optics and Photonics
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• v.1 no.6
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• pp.626-630
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• 2017

GaN-based green light-emitting diode (LED) structures suffer from low internal quantum efficiency (IQE), known as the "green gap" problem. The IQE of LED structures is expected to be improved to some extent by exploiting the Purcell effect. In this study, the Purcell effect on the IQE of green LED structures is investigated numerically using a finite-difference time-domain simulation. The Purcell factor of flip-chip LED structures is found to be more than three times as high as that of epi-up LED structures, which is attributed to the high-reflectance mirror near the active region in the flip-chip LED structures. When the unmodified IQE is 20%, the relative enhancement of IQE can be greater than 50%, without utilizing the surface-plasmon coupling effect. Based on the simulation results, the "green gap" problem of GaN-based green LEDs is expected to be mitigated significantly by optimizing flip-chip LED structures to maximize the Purcell effect.

• Journal of the Korean Professional Engineers Association
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• v.42 no.2
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• pp.41-48
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• 2009

The Government declared 'Low-Carbon Green Growth' as the new national vision for future development to improve economic growth and quality of life through higher energy efficiency, less energy consumption, wider use of renewable energy, etc. Korea can no longer delay participating in international efforts against global warming by reducing carbon dioxide and other greenhouse gas emissions. Thus low-carbon green growth is not a matter of choice, and it becomes indispensible to sustaining the nation's economic development. The Government is determined to take the initiative in speeding up economic recovery by carrying out the large scale investment projects such as the Korean version of a 'Green New Deal. The 49 trillion-won projects include river improvement, eco-friendly transportation networks, advanced information infrastructure, water resources & dam construction, green cars & clean energy development, etc. which will create nearly one million new jobs over the next four years.

• Environmental and Resource Economics Review
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• v.9 no.4
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• pp.773-799
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• 2000

The purpose of this paper is to measure the benefits of conservation of the green belt in the Greater Seoul area by CVM using dichotomous choice with a follow-up elicitation method. According to the government's plan, part of the green belt in the Greater Seoul area is to be freed from green belt designation. The mean willingness-topay(WTP) to conserve the green belt in the current state turns out to be about 7,430 won(95% confidence interval 6,220 - 8,640 won) per household, which amounts to 308 billion won per year for entire population of Seoul. This WTP figure is found to be significantly influenced by level of education, sex, and the variables related to the perception and attitudes of respondents.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.295-296
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• 2006

High hardness of P/M parts can be obtained in the cooling section of the sintering furnace by using sinter hardenable materials, thus the post-sintering heat treatment can be eliminated. However, the sinter hardened materials would have difficulties in secondary machining if it is required, which will limit the applications of sinter hardenable materials in the machined parts. Recent development in warm compaction technology can enable us not only to achieve the high green density up to $7.4\;g/cm^3$, but also the high green strength which is needed for green machining. Therefore by using warm compaction technology, the green machining can be applied to sinter hardenable materials for the high density, strength and hardness P/M parts. In the present study, a pre-alloyed steel powder, ATOMET4601, was used by mixing with 2.0% copper, 1.0% nickel, 0.9% graphite and a proprietary lubricant using a binder treatment process - FLOMET. The specimens were compacted and green machined with different machining parameters. The machined surface finish and part integrity were evaluated in selecting the optimal conditions for green machining. The possibility of applying the green machining to the high-density structural parts was explored.