• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1619-1629
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• 2013

It turned out that there was a direct or an indirect relationship among global warming, urban heat island effects, urban and traffic environments, and public's health. In particular, unusual climate phenomena such as frequent heavy rainfall and scorching heat in a row that had rarely happened before have a negative effect on quality of life for people living in urban areas. This study focuses on the effects of roadway geometric design and traffic conditions on air temperature of roadside in Seoul Metropolitan Areas, controlling of roadway micro-climate environment. Five roadway segments containing different roadway and traffic conditions in terms of traffic median with trees, street trees, traffic volume and average travel speeds were surveyed. According to statistical results(t-test) from three roadway air temperature regression model estimations, air temperature is found to be different from one another in three periods-morning, afternoon and evening. Regarding roadway geometric design, air temperature of urban roads with vegetated median strips is lower about 1.3~2.2 degrees in celcius. Higher traffic volumes per lane and lower average travel speeds will tend to increase roadside air temperature, and efficient traffic operation policies can protect from increasing roadside air temperature in urban areas.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.13-22
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• 2007

This study was carried out to scrutinize possibility of manufacturing pitch pine (Pinus rigida) glued laminated timber in order to add values of pitch pine trees. Also, it was investigated to improve bending performance of pitch pine glulam. Pitch pine was imported as one of major plantation species in Korean peninsula. Machine stress rated grades of pitch pine lumber mostly ranged between E7 and E9. which grades were more or less inferior to producing high quality glulam. However, the adhesive properties between pitch pine and pitch pine, and between pitch pine and Japanese larch (Larix kaempferi Carr.), such as shear bond strength, wood failure rate and de-lamination rate of bonded layer submerged in cold and boiling water, were higher than Korean Standard criteria. These properties are essential for manufacturing glulam with single species or multiple species. The modulus of rupture (MOR) of pitch pine glulam exceeded the criterion of Korean Standard for glulam strength grade but modulus of elasticity (MOE) was lower than the criterion. On the other hand, the bending performances (MOR and MOE) were improved 20 percent by mixing with Japanese larch laminar. It is effective to arrange higher quality Japanese larch laminar at the outer layer of glulam for improving bending performances. In conclusion, it is possible to use low quality pitch pine as laminar of structural glulam for adding values of pitch pine.

• Korean Journal of Environment and Ecology
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• v.10 no.1
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• pp.24-38
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• 1996

This study was conducted to investigate the Ecobridge district which connects green corridor from Central park to Pulkoksan and to establish of ecological space through analysis of avifauna community, plant community structure. In the results of analysis of avifauna, 3 species 23 individuals(Pica pica, Parus major, [asser montanus) in Ecobridge district, 5 species 37 individuals(Peca pica, Parus major, Passer montanus, Oriolus chinensis, Hirundo rustica) in Central park forest. There were 15 species 72 individuals in Pulkoksan. The plant community structure were classified of three types. As divided types were artificial forest(Pinus rigida, P. koraiensis, etc.) natural forest(Quercus mongolica, Q. serrata, Q. acutissima, Q. spp.) and semi-natural forest, which have shown the successional trends from the artificial forest to Quercus spp. community. The Ecobridge district was used as the space for the passers-by owing to its the simple vegetation. Species diversity was appeared that there was the order of Ecobridge district$\longrightarrow$Central park forest$\longrightarrow$Pulkoksan forest. Similarity index was calculated 20~23% between Ecobridge district$\longrightarrow$Central park, Pulkoksan forest. Therefore the highest species diversity and multistratum vegetation structure of Pulkoksan were the most suitable for the establishment to ecological space in the district.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.223-241
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• 2004

The purpose of this present study evaluated the osseous response around Ca-P coated xenogenic bone and compared osteogenic potential of Ca-P coated xenogenic bone to that of combination with type I collagen derived from bovine tendon as a biocompatible binder to prevent migration of bone particle on the repair of calvarial defects in rabbits. To study the effects of Ca-P coated xenogenic bone and collagen on bone healing, four 5-mm-diameter skull defect were made in calvaria with trephine filled with an autogenous bone chip or Ca-P coated xenogenic bone or Ca-P coated xenogenic bone and type I collagen (1:1 mixture by volume) or left empty. The defects were evaluated histologically at 1, 2, 4 and 8 weeks following implantation. Ca-P coated xenogenic bone at the calvarial defects of rabbits showed osteoconductivity at the margin of defect in the early stage of bony healing, but no direct contact with new bone was observed. With time passed by, it was resorbed slowly and showed consistent inflammatory reaction. An additional use of type I collagen derived from bovine tendon improved clinical handling, but no new bone formation was observed histologically. Above all, autogenous bone graft showed most prominent healing in quantity and density of new bone formation. According to this study, the use of Ca-P coated xenogenic bone alone and combination with type I collagen did not showed effective healing in quantity and density of new bone formation.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.140-147
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• 2016

A process for manufacturing virally-safe porcine bone hydroxyapatite (HA) has been developed to serve as advanced xenograft material for dental applications. Porcine bone pieces were defatted with successive treatments of 30% hydrogen peroxide and 80% ethyl alcohol. The defatted porcine bone pieces were heat-treated in an oxygen atmosphere box furnace at $1,300^{\circ}C$ to remove collagen and organic compounds. The bone pieces were ground with a grinder and then the bone powder was sterilized by gamma irradiation. Morphological characteristics such as SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) images of the resulting porcine bone HA (THE Graft$^{(R)}$) were similar to those of a commercial bovine bone HA (Bio-Oss$^{(R)}$). In order to evaluate the efficacy of $1,300^{\circ}C$ heat treatment and gamma irradiation at a dose of 25 kGy for the inactivation of porcine viruses during the manufacture of porcine bone HA, a variety of experimental porcine viruses including transmissible gastroenteritis virus (TGEV), pseudorabies virus (PRV), porcine rotavirus (PRoV), and porcine parvovirus (PPV) were chosen. TGEV, PRV, PRoV, and PPV were completely inactivated to undetectable levels during the $1,300^{\circ}C$ heat treatment. The mean log reduction factors achieved were $${\geq_-}4.65$$ for TGEV, $${\geq_-}5.81$$ for PRV, $${\geq_-}6.28$$ for PRoV, and $${\geq_-}5.21$$ for PPV. Gamma irradiation was also very effective at inactivating the viruses. TGEV, PRV, PRoV, and PPV were completely inactivated to undetectable levels during the gamma irradiation. The mean log reduction factors achieved were $${\geq_-}4.65$$ for TGEV, $${\geq_-}5.87$$ for PRV, $${\geq_-}6.05$$ for PRoV, and $${\geq_-}4.89$$ for PPV. The cumulative log reduction factors achieved using the two different virus inactivation processes were $${\geq_-}9.30$$ for TGEV, $${\geq_-}11.68$$ for PRV, $${\geq_-}12.33$$ for PRoV, and $${\geq_-}10.10$$ for PPV. These results indicate that the manufacturing process for porcine bone HA from porcine-bone material has sufficient virus-reducing capacity to achieve a high margin of virus safety.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.2
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• pp.60-76
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• 2020

The purpose of this study was to examine the spatial and visual arrangement characteristics of Imsil Yi Ung-jae's old house's spatial and visual aspects in order to discover the value of landscape and traditional house garden. The results of this study are as follows. Dongchon-village in Dundeok-ri, where old house is located, is a typical form of with "Back to the mountain and facing the water(背山臨水)", and is located in the north of the three streams of water, forming a Jeonchaghugwan(前窄後寬). Dongchon Village, which has a traditional scenic spot between Danguidae(丹丘臺) and Samgyeseokmun(三溪石門), is understood to be the main street of Nojeokbong Peak and Gyegwanbong Peak, which is Ansan(案山), where the "A centipede flying in the sky(飛天蜈蚣形)". Yi Ung-jae's old house is the oldest existing high-priced house in the North Jeolla region and the closing price of a royal family of the Joseon Dynasty, which was arranged by Chunseongjeong(春城正), Yi Dam-son(李聃孫) in the mid-16C. The Japanese Invasion of Korea in 1592 and Japanese colonial era, the loyalty of the gate quarters, the filial piety of the gate quarters, and the faithfulness of the tablet(扁額) and Juryeons(柱聯) are enough to contribute to the rise of the value of a physical house. The men's quarters(Sarangchae), which are placed on a high-pocket or a layout without going against the sloping terrain, have the effect of making the distance as far as possible, enhancing its dignity and hierarchy as a royal building. In addition, the entrance to the main quarters(Anchae) through the four pillar gates(四柱門), the extensive support and the appropriation of the Chaewon(vegetable garden), and the official base for the Anchae are very unique compared to the general nobility. However, in the context of the postwar relationship, the shrine seeks to realize Confucian ideals while harmonizing with nature by arranging wide sponsorships around it. On the other hand, it is confirmed that there was a pond in the form of a circle in a square(方池圓島型) with a relatively large area, which is now disturbed and damaged. Written by the high priced planting species are sponsored pine trees, hackberry, persimmon trees, Japanese apricot flower, Ohmomiji, and plum tree in the side garden, as well as cotyledon trees in the outside garden. However, although flower bed(花階), which is built on the stone axis, is a place that clearly shows the expensive garden, it seems to have lost the texture of the plant due to the extremely high variety of species and the splendor that does not match the plant landscape of the flower world. Yi Ung-jae's old house is highly valuable as it is a portrait house of a prince of the blood in the mid-Joseon Dynasty. Based on these findings, this study proposed a plan to improve the management of high prices that could be met.

• Journal of Environmental Impact Assessment
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• v.32 no.6
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• pp.437-449
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• 2023

This study measured PM₁₀ concentrations and wind speeds in buffer green spaces and neighborhood parks located along the road, and compared them with roadside measurementresults to understand the effect of mitigating PM₁₀ concentrations by type of green space and the influence of wind speeds on it. As a result of the analysis, the effect of mitigating PM₁₀ concentration was different depending on the type of roadside green space, and an increase in wind speed had a significant effect on reducing PM₁₀ concentration. In buffer green areas with high planting density, wind speed was low and PM₁₀ stagnated inside, resulting in the highest concentration. On the other hand, green areas in neighborhood parks with relatively low planting density had high wind speeds and the lowest PM₁₀ concentration. The non-green area within the neighborhood park recorded the highest wind speed, which was advantageous for the spread of PM₁₀, but the concentration was higherthan that of the green area. Therefore, in orderto reduce PM₁₀ concentration in roadside green space, it is necessary to create green space with good ventilation, and the combined effect of green space and wind speed seems to be more advantageous in reducing PM₁₀ concentration. Green spaces capture and remove PM inside, contributing to reducing the concentration of PM outside. In order to manage PM in the entire city and on roads, it is necessary to increase planting density and leaf area in roadside green spaces, such as buffer green spaces, so that PM can be removed within the green spaces. However, in green spaces such as neighborhood parks that are actively used by city residents, in orderto minimize damage to users due to PM, it is desirable to create green spaces with a structure that allows PM to spread to the outside rather than stagnate inside.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.3
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• pp.77-91
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• 2015

This study aims to suggest adequate soil management through the analysis of physicochemical properties of soil in the planting grounds of Incheon International Airport, which was constructed on a massive land reclamation site. Study areas were 5 sites at the international business complex, the passenger terminal, the airport support complex, the free trade zone, and the access road. Soil profile analysis showed that 9 plots out of the 27 plots were hardpan and heterospere within 80cm from the soil surface. The earth laid on the ground was categorized as gravel based soil(4 plots), dredged soil from the sea bottom and mixed reclamation materials(2 plots), clay with poor permeability(3 plots) and waste construction material(1 plot). Average soil hardness was $11.5kg/cm^2$ and soil textures were sandy soil, sandy loam and loamy sand. Average soil pH was 6.7 and average organic matter content was 0.7%. Electrical conductivity was 0.0dS/m and exchangeable cation concentrations were $Ca^{2+}$ 3.4cmol/kg, $Mg^{2+}$ 1.5cmol/kg, $K^+$ 0.3cmol/kg and $Na^+$ 1.0cmol/kg. Average cation exchange capacity was 11.0cmol/kg. Although average figures in Solum mostly meet the landscape design criteria, properties of each soil layer showed various values sometimes over the limit. Base saturations were $Ca^{2+}$ 29.9%, $Mg^{2+}$ 13.3% and $K^+$ 3.7% for lower soil, $Ca^{2+}$ 33.3%, $Mg^{2+}$ 17.0% and $K^+$ 2.7% for mid-soil and $Ca^{2+}$ 32.6%, $Mg^{2+}$ 12.2% and $K^+$ 1.9% for upper soil. Exchangeable sodium percentages were 16.4% for lower soil, 7.5% for mid-soil and 4.7% upper soil. Sodium adsorption rates were 0.8 for lower soil, 0.3 for mid-soil and 0.2 for upper soil. Factors affecting to the vegetation growth were heterogeneity and poorness of solum, disturbance of dredged soils, high soil hardness including hardpan in the subsurface soil layer and shallow effective soil depth, high soil acidity, imbalance of base contents, low organic matter content and low available phosphate levels in the soil.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.129-136
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• 2010

This study was initiated to investigate thatch accumulation in several turfgrasses grown under two soil systems. The 45 centimeter deep USGA system was constructed with rootzone, intermediate and drainage layers. The mono-layer system, however, was made with only a 30cm rootzone layer. Turfgrasses used in the study were comprised of 3 varieties from Korean lawngrass of Warm-Season Grass(WSG) and 3 blends and 3 mixtures from Cool-Season Grass(CSG). A total of 9 turfgrass treatments were replicated three times in RCBD in both systems. Cultural practices for the research plot followed a typical maintenance program for highly managed turf. Treatment differences for thatch accumulation were observed among the turfgrasses in both soil systems. Thatch under the USGA system was 9% greater than under the mono-layer system due to its more favorable conditions for turf growth. Higher thatch depth was found with Korean lawngrass, 34~87% in the USGA system and 16~75% in the mono-layer system when compared with CSG. Among WSG, the Joongji variety was the highest in thatch layer under both the USGA and mono-layer systems. Kentucky bluegrass(KB) was the greatest among CSG, since it is a rhizomatous-type in growth habit, resulting in faster production of organic matter over bunch-type of tall fescue and perennial ryegrass. Proper depth in the thatch layer was known to be beneficial by enhancing the resiliency and wear tolerance of the turf in athletic fields. Thus, KB was considered to be a very excellent turfgrass in terms of turf quality, environmental performance, physical properties and soccer player safety. However, disadvantages such as poor water-holding properties, more inclined to injury from environmental stresses and severe diseases and insect injury were also expected where thatch was excessively accumulated. Therefore, these results demonstrate that more frequent measures for controlling thatch such as vertical mowing, topdressing or coring should be employed for soccer fields with Korean lawngrass and KB over other turfgrasses.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.129-144
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• 2010

We have studied the changes of the environmental and vegetational factors according to the hydro-seral stages in the shoreline of the lagoons, Korea. We have divided seral stages into 7 stages from open water stage to the stratified forest stage considering as the characteristics of water body, dominance of submerged and emergent plant, and development of the shrub, subtree and tree layer. According to the successional stage, water depth gradually decreased and water quality changed from seawater to brackish water and from brackish water to fresh water, organic matter in a soil layer gradually increased, and the litter layer grew up. As the development of the vegetation structure, the life-form of the vascular plants changed as follows; open water ${\rightarrow}$ submerged plant and floating-leaved plant ${\rightarrow}$ emergent plant and submerged plant ${\rightarrow}$ emergent plant ${\rightarrow}$ emergent plant, mesophyte and scrub ${\rightarrow}$ mesophyte. In the late seral stage, the 3 different forest types were established by the water retention or drainage and nutrient accumulation of the soil layer. Salix dominant forest developed in the wetted sites, the forest type dominated by Pinus thunbergii, Carex pumila and mesophytes developed in the well drained sites causing by sand substrate, and the forest type dominated by the planted or ruderals such as Pinus densiflora, Robinia psedo-acacia, Festuca ovina, Setaria viridis ect. developed in the sites composed of forest soil introduced by artificial reclamation.