• Wind and Structures
• /
• v.28 no.4
• /
• pp.215-224
• /
• 2019

Because of the particularity and complexity of direct air-cooling structures (ACS), wind parameters given in the general load codes are not suitable for the wind-resistant design. In order to investigate the wind loads of ACS, two 1/150 scaled three-span models were designed and fabricated, corresponding to a rigid model and an aero-elastic model, and wind tunnel tests were then carried out. The model used for testing the wind pressure distribution of the ACS was defined as the rigid model in this paper, and the stiffness of which was higher than that of the aero-elastic model. By testing the rigid model, the wind pressure distribution of the ACS model was studied, the shape coefficients of "A" shaped frame and windbreak walls, and the gust factor of the windbreak walls were determined. Through testing the aero-elastic model, the wind-induced dynamic responses of the ACS model was studied, and the wind vibration coefficients of ACS were determined based on the experimental displacement responses. The factors including wind direction angle and rotation of fan were taken into account in this test. The results indicated that the influence of running fans could be ignored in the structural design of ACS, and the wind direction angle had a certain effect on the parameters. Moreover, the shielding effect of windbreak walls induced that wind loads of the "A" shaped frame were all suction. Subsequently, based on the design formula of wind loads in accordance with the Chinese load code, the corresponding parameters were presented as a reference for wind-resistant design and wind load calculation of air-cooling structures.

• Korean Journal of Environment and Ecology
• /
• v.24 no.5
• /
• pp.503-518
• /
• 2010

The Wando Jeongdo-ri Windbreak Forest is located in region of Wando, where located between sea and land facing with the southward. Due to the strong winds from the southeast in the summer season, it is very important sites as an ecological succession areas that protect cultivated land and the fishing village. Flora of Wando Jeongdo-ri Windbreak Forest is recorded as 384 taxa with 93 families 250 genera 355 species 42 varieties and 7 forms. The Jeongdo-ri Windbreak Forest belongs to South coast province, and appeared Cymbidium nipponicum as Endangered Plant Species II. Rare Plants are recorded as 6 taxa; C. nipponicum, Arisaema heterophyllum, Lilium distichum, Koelreuteria paniculata, Monotropa uniflora and Ardisia macrocarpa. The Protection species which is designated by the CITES are 2 taxa; Cymbidium goeringii and C. nipponicum. Protection species of IUCN is 1 taxa; Cinnamomum japonicum. Endemic plant are 7 taxa; Poa annua, Polygonum lasianthum var. coreanum, Chloranthus fortunei, Carpinus coreana and Lonicera subhispida. The naturalized plant is recorded as 32 taxa with 11 families 23 genera 27 species 5 varieties. The Naturalization Index was 8.33%, and the Urbanization Index was 11.81%.

• Journal of Korean Society of Forest Science
• /
• v.97 no.1
• /
• pp.95-101
• /
• 2008

The wind speed reduction capability of forest belt of Caragana Korshinskili Kom in Yanchi, Ningxia province in China is as follows. 1. At the height of 0.5 m, the windbreak effect is 3-Strip (30.22%) > 2-Strip (26.53%) > 1-Strip (16.28%) from 1H (H = Tree Height) to 5H, and the windbreak effect is 2-Strip (16.11%) > 3-Strip (12.79%) > 1-Strip (9.82%) for greater than 7H. Further analysis of 2-Strip and 3-Strip revealed that the wind reduction effect of 2-Strip spread to 44H and 3-Strip spread to 27H. This result implies that 3-Strip is most effective for short distances and 2-Strip is most effective for long distances. 2. At the height of 1.0m, the wind speed was relatively constant and the reduction rate of wind speed had a minimal variation, with the reduction rate of 1-Strip (8.04%), 2-Strip (8.23%), and 3-Strip (7.43%). 3. The sandbreak effect is 2-Strip (55.28%) > 3-Strip (37.13%) > 1-Strip (20.87%). Especially, The rate of sandbreak of 1H (86.06%) of 2-Strip is most effective value in whole data.

• Proceedings of the Korean Society of Environment and Ecology Conference
• /
• 2007.10a
• /
• pp.108-111
• /
• 2007

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1986.06a
• /
• pp.78-79
• /
• 1986

• Proceedings of the Korean Society of Environment and Ecology Conference
• /
• 2009.10a
• /
• pp.158-161
• /
• 2009

• Proceedings of the Korean Society of Environment and Ecology Conference
• /
• 2009.10a
• /
• pp.162-165
• /
• 2009

• Korean System Dynamics Review
• /
• v.15 no.3
• /
• pp.81-104
• /
• 2014

This study aimed to suggest the directions for the landscape protection of Sindu-ri coastal dune based on its ecological system. The study investigated ecological systems of the coastal dune followed by damage causes of coastal dune according to the land use change, and landscape value of coastal dune in the study area. In order to construct causal-effect feedback loop, systems thinking was performed. Result of this study showed that the area of coastal dune and the amount of sand are maintained by the interaction with sand beach while they are affected by wind direction, wind speed, and dune plants. It was also found that the changes of land use pattern, increasing commercial area, and planted windbreak forest damaged to the coastal dune. In addition, size of coastal dune and growing number of dune plants increased landscape value of coastal dune and tourist draw. However increasing tourists have constantly affected land use changes and have damaged to coastal dune area. In sum, planning for land use regulation, rest-year system areas, promotion and education for coastal dune, dune plants protection, and windbreak management should be taken into account for landscape protection in coastal dune.

• Wind and Structures
• /
• v.38 no.6
• /
• pp.411-425
• /
• 2024

To investigate the optimal aerodynamic parameters of wind barriers for the T-beam of high-speed railway (HSR) bridge and the wind field of the wind barrier-train-bridge system, the three-component forces of the system and the wind pressure on the vehicle surface were tested and analyzed through the sectional model wind test. The effects of wind velocity, with/without wind barrier, the height of wind barrier, and the air permeability of the wind barrier on the aerodynamic characteristics of the train-bridge system are discussed. Additionally, a CFD numerical model is constructed to evaluate the wind environment of the bridge surface with/without the wind barrier, and the impact of wind barrier on the running safety of vehicles are analyzed. Comprehensively considering the running safety of the train and the wind-resistant stability of the bridge, it is more appropriate to set the wind barrier height H as 3.5 m and the porosity 𝛽 as 30% respectively.

• Korean Journal of Environment and Ecology
• /
• v.27 no.1
• /
• pp.85-98
• /
• 2013

In order to propose effective conservation management plan, this study verified ecological characteristics, humanities and Social characteristics. The research site is private property which is owned belonging to the Kim's of Gimhae that have long history. The study site is more than a thousand years old and was created for protecting from typhoon. There held the religious ritual what is called Dongsinje until 1960s. There have been protected and managed by the villagers. As the results of analysis, the area of windbreak are $12,392.69m^2$. The windbreak is dominated old years deciduous broad-leaved tree such as Zelkova serrata, Celtis sinensis, Aphananthe aspera. Around there were farmlands(52.1%), urbanized area(26.3%), forest area(16.6%). The vegetation communities of windbreak were classified by considering the dominant species and current status of forest. The forest types are following as; A. aspera community(I) which is using less pressure, Platycarya strobilacea-Carpinus coreana-Z. serrata community(II). Z. serrata community(III) which is using high pressure, Z. serrata-A. aspera community(IV), Z. serrata community(V) which is damaged under canopy trees. The windbreak was in good condition whereas, there were concerns the some wrong status was being undermined such as the wrong forest restoration projects in the past, the trails that is penetrating inside the forest, building up education facilities. Therefore, in order to restore the value of windbreak what is so called Suwol forest, we should improve the problems of forest ecosystem such as wrong management, forest fragmentation by facilities and decline in forest by lack of growing the next generation trees. In addition, we should remove excessive resting facilities and lead to passive use of forest. to improve the way of wrong management, moreover, we should close off he trails that is penetrating inside the forest for improving fragmentation. We should restore vegetation restoration and fostering the next generation trees for forest ecosystem. In order to restore unique of histo-cultural and ecological forest landscape, the next generation trees should be grown up that is the dominant species in Suwol forest. Moreover, as a results of comparing the between good vegetation communities and damaged vegetation communities, it is necessary to complementary planting for demeged vegetation communities, therefore there needs to 10.8 under canopy trees, 79.7 shrubs.