• Journal of Forest and Environmental Science
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• v.33 no.4
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• pp.348-354
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• 2017

Agroforestry has been practiced in arid and semi-arid regions for the purposes of preventing desertification and to increase income for locals. However, the intended effects of such practices have been limited due to strong winds and aridity. This study undertook multi-year monitoring of the productivity of income crops associated with windbreak planting in a semi-arid region of Mongolia, and explored strategies of windbreak planning to enhance the multi-purpose effects of agroforestry practices. The tree crown density of windbreak planting was on average 40% in one year after planting and 65% 2-3 years after, and thereby windspeeds were reduced by about 30% and 54%, respectively. Average windspeed reductions at leeward distances from the windbreak planting were approximately 60% within 3H (H=tree height), 50% at 5H, and 42% at 7-9H, presenting a pattern in which the farther the distance the less the reduction in windspeeds. The windbreak planting increased crop productivity by up to 6.8 times, compared to the productivity absent of windbreaks. Increases in the crown density as stated above resulted in increases of crop productivity by up to 3.6 times. Based on such results, this study proposed a model of windbreak planning as a typical land-use system of border windbreak planting or alternate windbreak planting of combining trees and income crops. The model also included tree planting with a crown density of 60% and allocation of income crops within a leeward distance of 5 times the height of the trees to reduce windspeeds by about 50%. The results from this study are applicable to practicing agroforestry not only at the study site but also in other regions worldwide where strong winds and aridity are problematic.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.4
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• pp.15-29
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• 2021

Urban green spaces offer a variety of benefits to living things and humans. However, existing green spaces have been reduced and fragmented due to urbanization, and there is a limit to creating new large green spaces in densely developed cities. Street trees have fewer restrictions on land use, which can be a measure to secure green areas in cities. In Korea, excessive pruning is being done on some street trees for reasons such as blocking of building signboards, contact with electric wires, and restrictions on sidewalk widths. Therefore, it is necessary to quantitatively understand the relationship between the benefits provided by street trees and their structures to come up with an efficient and systematic planning and management plan for urban street trees. In this study, we quantitatively analyzed the relationship between the thermal comfort improvement by the shades of street trees and the vertical structure, planting environment, and types of street trees. To calculate the thermal comfort felt by human body, we calculated UTCI (Universal Thermal Climate Index) of each street tree. For the vertical structure of street trees, we used Terrestrial LiDAR and the point clouds of street tree's crown was sliced vertically at 1m intervals. We conducted a multiple regression analysis on the thermal comfort improvement using the variables we obtained from fields. As a result, in the case of a street tree's vertical structure, the lager the volume of tree's crown located 3-4m (β=0.298, p<.05) and 6-7m (β=0.568, p<.001) above clear length, the better the cooling effect. In addition, the thermal comfort improvement was assessed to decrease as the DBH increased (β=-0.435, p<.001). In general, the crown diameter and DBH are positively correlated, with a cooling effect occurring as crown diameter increases. In this study, the opposite result was obtained due to the small number of trees measured, so additional research is needed by increasing the number of tree samples. In the case of the planting environment, the effect of improving thermal comfort was higher in the shaded area of trees planted to the south (β=-0.541, p<.001). Since unsystematic management of street trees can deteriorate the function of them, quantitative evaluations of the vertical structure of street trees are required, which can provide specific measures for planning and management of urban street trees with thermal comfort effect.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.2
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• pp.21-38
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• 2024

This study aims to establish an efficient street green area to improve the urban thermal environment and enhance pedestrian thermal comfort. Specifically, This study identified parameters applicable to green space planning and design, analyzed thermal environment mitigation mechanisms for each parameter, and, based on these findings, proposed methods for tree species selection and planting in green space planning and design. To achieve this, 61 papers were selected through a four-stage process from both domestic and foreign sources. The selected papers were analyzed, and the following main results were derived: In open street canyons with high stress levels due to low aspect ratios and high sky view factors(SVF), broadleaf trees with wide crown widths, low trunk heights, high leaf area index(LAI), and high crown heights were found effective in reducing heat, thereby increasing the amount and quality of shade. In contrast, in deep and narrow street canyons with relatively low heat stress due to high aspect ratios and low SVF, broad-leaved trees with narrow crown widths, high trunks, low crown heights, and low LAI were effective in reducing heat by enhancing ventilation. This study can serve as fundamental data for establishing standards for street green spaces to improve the thermal environment of street canyons and enhance thermal comfort of pedestrians. Additionally, it can be valuable when selecting the location and prioritizing street green spaces. Moreover, it is anticipated to be a foundational resource for creating guidelines for green space planning and design in response to climate change.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.1
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• pp.77-88
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• 2011

This study was carried out to investigate the effects of soil depth and planting density on the growth of lettuce, crown daisy, and strawberry on a rooftop condition using artificial soil as a growth media. The vegetable crops showed better growth for plant height (cm), plant width (cm), plant fresh weight (g), and Fo, Fm and Fv/m on 20cm depth soil than 10cm depth soil except strawberry. Planting density of $16/m^2$ and $64/m^2$ did not show significant differences on the growth of the crops. Soil moisture content and EC were low for 10cm depth soil in lettuce plots, whereas there was no significant differences on soil moisture and EC between two soil depth in strawberry plots. Hunter's L, a, and b values showed the leaf color of lettuce dark green on 20cm depth soil and reddish on 10cm depth soil. Results showed that soil depth suitable for crop growth on rooftop conditions was 20cm rather than 10cm. Growth response of the crops showed no significant difference between $16/m^2$ and $64/m^2$, indicating that planting density of 64 $plants/m^2$ could be practiced on rooftop conditions. Lettuce growth rapidly changed in control treatment in which leaves were not pinched out, while slowly changed in plants which leaves were periodically pinched out. In the case of control plot, it was impossible to harvest because withering of lower leaves after blossom on June 22. The plant of crown daisy in which pinching was not conducted, blossomed on June 7, and the plants were removed since its aesthetical value was lost. Strawberry seemed to be a suitable vegetable crop for rooftop conditions based on its high covering rate and extended growth period until late October. The soil depth 20cm and planting density 64 $plants/m^2$ were suitable for vegetable crops on green roof system using artificial soil.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.793-799
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• 2016

This study examined Platanus orientalis and Ulmus davidiana planted in downtown parks to identify the correlations among microclimatic factors such as temperature in the crown, air flow, and wind speed. For the field survey, measurements were taken at 1 hour intervals from 09:00 am to 06:00 pm in August. For the measurement of microclimatic factors, data on temperature, light intensity, air flow, and wind speed were collected using a quantum sensor (PAR Quantum Sensor SKP215), a precision thermometer (Pt1000-Sensor), and a combination anemometer (1467 G4 & HG4). The results of the analysis demonstrated that both Platanus orientalis and Ulmus davidiana, showed a greater cooling effect inside the crown as compared with the outside temperature. The cooling effect inside the crown was more evident with air flow and wind speed factors. With relation to wind, the inner temperature of the crown of Platanus orientalis decreased due to air flow while that of Ulmus davidiana decreased due to wind speed. With no wind, the average variation in temperature inside the crown was $-0.9^{\circ}C$ for Ulmus davidiana and $-0.958^{\circ}C$ for Platanus orientalis, indicating that Platanus orientalis was relatively more effective in lowering the temperature of the planting space than Ulmus davidiana. This study is significant because it shows that different tree species have different effects on the microclimate and that factors affecting the formation of the microclimate of trees may vary with species. Further studies on species other than broad leaf trees, such as evergreen trees and shrubs, are required in order to plan the distribution of landscaping trees that are effective in regulating the microclimate within urban green spaces.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.34 no.2
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• pp.27-36
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• 2022

The large uprush could be occurred when the waves hit the coastal structure and this uprush by wave could make the overtopping. The downfall of the wave overtopping water over the structure brought about the vertical impact loads. The vertical impact loads should be evaluated in order to design the pavement behind the crown wall however these loads were still unclear. In this study, the hydraulic model tests for the downfall impact loads by wave overtopping were performed and the various conditions were applied to the tests. The effect of the incident wave condition, the freeboard, the armour crest height and the height of the parapet were investigated. The test results showed that the parapet on the crown wall could reduce the wave overtopping however the inclusion of parapet could lead to the increased downfall wave pressures behind the crown wall. The empirical formulae were proposed for evaluating the maximum downfall pressures behind the crown wall of rubble mound structure.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.1
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• pp.111-117
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• 2014

The aim of this study is to find out the pattern of Ger form, inner spatial composition of Mongolian Ger house, and to take a dig at the structural or symbolic elements of nomadic architecture of Ger. To the point of view of corresponding to living and space of housing, remarkable characteristics of Ger Architecture is able to pull down and recombine the structures of nomadic house. Even though urbanization of Mongolia has spreading rapidly in a whole nation, most of people preserves traditional housing pattern within Ger. The ways of survey are to study of traditional home of Mongolia, and then field work at residence or mountain area in Ulan Bator and Gorkhi Terelj National Park area. This survey contains the form, size, structure, spatial composition of living space, structure, and materials. There are three results as follows: First, the form of Ger house is like a pyramidal or crown roof style to approximate to the round shape of it. Usually they had lived in nomadic way of life, so the Ger had a movable and flexible structure. Second, the Ger is easy to build up and deconstruct to move or find a new pasture. Third, the Mongolian Ger structure is composed by mainly five elements that are Khana, Khaalga, Toono, Bagana, and Uni. It has a hierarchy of internal spaces which are classified to gender, orientation, and property.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.1 s.114
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• pp.10-20
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• 2006

This study is to introduce the improvement and management of Ecoduct located in Uiwang's Mt. Obong, Gyeonggi province. The inner planting of Ecoduct is not very related to the flora of mountain areas nearby. The difference in the index of plant crown volume(GVZ), the similarity index(S.I.), and monitored animals is significant between Ecoduct and mountain areas. Putting together all of the results, the initial selection of movement and target species is excessive in number. Target species must be selected again. They will be species that are currently found on the site. The Ecoduct space must be divided into two parts: buffer planting space and wildlife corridor. Reforestation is needed since the GVZ is remarkably lower in Ecoduct than in the nearby mountain areas. Besides the vegetation of Ecoduct is densely planted in guidance planting space to connect the southern Quercus mongolica community and the northern Quercus acutissima community. Proper upkeep after construction should be continuously conducted to maintain the procedure of natural change.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.398-407
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• 2021

This study intended to identify causes of poor tree vigor in the Hanbando coastal forest by investigating its geographical environment, climate condition, soil physicochemical characteristics, and growth condition of Pinus thunbergii. It divided the forest into an area with poor tree vigor or dead standing trees and a control area with good tree vigor and examined them separately. The survey showed that stand density was significantly higher in the area with poor tree vigor. In contrast, the crown width in the area with good tree vigor was wider. The number of dead standing trees and the stand density showed a negative correlation. The stand density and diameter at breast height (DBH), tree height, crown height, and crown width also showed a negative correlation. The result indicated that, as the tree's stand density increases, the crowns of individual trees overlapped and the lower branches died. Then crown height and crown width decreased, and the number of leaves and photosynthesis was reduced, leading to lower tree height and weaker growth of breast diameter. As a result, tree vigor weakened, and combined with environmental pressures from the lack of moisture and nutrients in coastal soil and salty wind, P. thunbergii in coastal areas is expected to die massively. Although the causes of dead standing trees and poor tree vigor of P. thunbergii in the Hanbando coastal forest are complicated, poor management of adequate tree density in response to the growth of P. thunbergii is the primary cause. The secondary cause is external environmental pressures, including unfavorable soil conditions and salty and strong wind that obstruct the growth of P. thunbergii.

• Journal of architectural history
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• v.8 no.3 s.20
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• pp.53-64
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• 1999

The subjects of the research is the architecture expressed traditionality from the time of the Open Port on, including North Korea region. The scope is divided into three periods; the first is from the Open Port to the Rehabilitation (光復),1945, the second is from then to 1960, and the last is from 1960 to the present. The expression of Koreanity(韓國性) should be concerned with the states at the time. In the beginning of the first period the alienate culture and the new modern facilities, like electricity, telecommunication system, train service, etc., rushes to Korea and the traditional architecture accepted the most of the new-comings; therefore, the original form was transformed. That seems to be the beginning of the discourse on traditionality in Korea architecture. The expression was showed up in four parts: ${\bullet}$ Korea traditional architecture accepting the foreign culture and the modern facilities ${\bullet}$ the compromise between foreign and traditional architectural form ${\bullet}$ the compromise between the Modem and traditional architecture ${\bullet}$ the Imperial Crown Style(帝冠樣式) which is the eclectic architecture with transformed roof. The figurative expression in the present architecture was showed up in roughly two parts: ${\bullet}$ the traditional form directly depicted wholly / partially ${\bullet}$ the abstract traditional form wholly / partially Moreover the results on the research traditional architecture have been collected, the principles have been drawn out. Especially the first beauty is not on form or figure of a building but on the composition of architectures and the harmony of the natural circumstances and architectures. So many contemporary architects make efforts to apply the principles to the composition and formation of current architecture.