• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.516-525
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• 2011

We studied the influence certain environmental factors (proximity of roosting site, roads, and residential areas) have on the spatial distribution of cranes in the Cheorwon, Korea. Using a range finder and GPS, data were collected from January to February 2007 and were subsequently evaluated with ArcGIS. The size of the cranes' wintering habitat was estimated to be 7$76.9km^2$. Five hundred and fifty-five flocks of cranes were observed and detailed distributions were collected. Feeding distribution of the cranes showed clustered distribution, however, no tendencies of spatial autocorrelation were apparent. Adjacent regions with paved roads and residences showed lower densities than other areas. Distances at which paved roads and residential areas induced changes in feeding flock densities were 1500m and 1750m, respectively. Feeding flock density decreased with increased distance from roosting site. Feeding flock density of the two crane species did not increase as distance from roads increased, however, the density of individuals showed a significant increasing tendency with increased distance from roads. In both species, density of feeding flocks and individuals significantly increased with increasing distance from residential areas. In Red-crowned Cranes, the density of feeding flocks and individuals significantly decreased with increasing distance from roosting site, however, in the case of White-naped Cranes, there was an even distribution in density of feeding flocks and individuals.

• Journal of Korean Association for Spatial Structures
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• v.8 no.3
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• pp.45-51
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• 2008

A single layer-latticed dome is advantageous for large span structures because it is very stiff despite the light weight of the structure itself. However, this structure becomes easily unstable during erection due to its large size. The Block method is popular with the large span structures. A partial block of the dome is fabricated on the ground and lifted by crane to a designated location of structures. The lifting point selection is very important to create a stable erection and to avoid buckling of members during the erection. The purpose of this study is to analyze the structural behaviors and buckling characteristics according to the lifting point of single-layer latticed domes with triangle network in order to take materials about the safe and economic erection. The conclusions are obtained as follow. 1) The buckling strength of the block part varies with the location of lifting points when it is erected. In case, the height of the dome is lower, the effort of buckling strength of the structure is higher. 2) In buckling strength, the effect of the lifting rope length is smaller than it of the lifting points change.