• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.146-153
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• 2010

Urban development typically results in many species being confined to small, isolated and degraded habitat fragments. Fragment size and isolation underpin many studies of modified landscape to prevent biodiversity loss. However, habitat characteristics such as vegetation structure and edge effects are less frequently incorporated in planning. The relative influence of biogeographic (e.g. size, isolation) and vegetation parameters on assemblages is poorly understood, but critical for conservation management. In this study, the relative importance of biogeographic and vegetation parameters in explaining the diversity of forest-interior dwelling birds in forest fragments in Chungcheong Province Area. Fragment size and vegetation characteristics were consistently important predictors of bird diversity. Forestinterior bird richness was influenced by fragment size (0.437), wood age (0.332), wood diameter (0.068), and patch shape (-0.079). To preserve bird diversity of Chungcheong Province Area, it is important to consider differing responses of bird diversity to landscape change, move beyond a focus primarily on spatial attributes (size, isolation) to recognize that landscape change also has profound effects on habitat composition and quality. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale.

• Fashion & Textile Research Journal
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• v.22 no.1
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• pp.94-101
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• 2020

This helps plus-size consumers purchase ready-made clothes and improves fitness by analyzing the upper body shapes of abdomen-obese adult males; in addition, it creates a size system based on each size interval of obesity shapes. The criteria for the 572 male subjects surveyed were over 25 kg/㎡ of the BMI, over 90 cm of waist, and over 0.85 waist hip ratio. The results were as follows. First, the higher the age group, the higher the degree of abdominal obesity in each age group. The degree of obesity decreases age increase; however, was the risk of abdominal obesity increased. Second, Compared to standard body types, the average body size of Abdomen-obese males is significantly larger, especially in the waist area than in the chest area. Third, to propose a size system for abdominal obese adult males, 16 sections with a final 2% rate of appearance were finally adopted as suit-tops size system for abdominal obese adult males by applying a 3 cm dimension gap between each designation as specified in the KS standard. The coverage ratio for the 16 sections was 72.6% and the coverage effienciency was 4.5%. The results of this study can be used in a various clothes; in addition, the activation and segmentation of the plus-size market are also believed to be significant.

• Atmosphere
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• v.17 no.4
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• pp.381-391
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• 2007

The characteristics of flow around a single obstacle with fixed height and varied length and width are numerically investigated using a computational fluid dynamics (CFD) model. As the obstacle length increases, flow distortion near the upwind side of the obstacle increases and the size of the recirculation zone behind the obstacle also increases. As the obstacle width increases, the size of the recirculation zone decreases, despite almost invariable flow distortion near the upwind side of the obstacle. Flow passing through an obstacle is separated, one part going around the obstacle and the other crossing over the obstacle. The size of the recirculation zone is determined by the distance between the obstacle and the point (reattachment point) at which both the flows converge. When the obstacle width is relatively large, flows are reattached at the obstacle surface and their recoveries occur. Resultant shortening of the paths of flows crossing over and going around decreases the size of the recirculation zone. To support this, the extent of flow distortion defined based on the change in wind direction is analyzed. The result shows that flow distortion is largest near the ground surface and decreases with height. An increase in obstacle length increases the frontal area fraction of flow distortion around the obstacle. In the cases of increasing the width, the frontal area fraction near the upwind side of the obstacle does not change much, but near the downwind side, it becomes larger as the width increases. The frontal area fraction is in a better correlation with the size of the recirculation zone than the building aspect ratios, suggesting that the frontal area fraction is a good indicator for explaining the variation in the size of the recirculation zone with the building aspect ratios.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.189-196
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• 2007

Allometry, basal area equations, and volume equations were developed with various tree measurement variables for the major species, Quercus mongolica and Quercus variabilis, in Korean natural hardwood forests. For allometry models, the relationships between total height-DBH, crown width-DBH, height to the widest portion of the crown-total height, and height to base of crown-total height were investigated. Multiple regression methods were used to relate annual basal area growth to tree variables of initial size (DBH, total height, crown width) and relative size (relative diameter, relative height) as well as competition measures (competition index, crown class, exposed crown area, percent exposed crown area, live crown ratio). For tree volume equations, the combined-variable and Schumacher models were fitted with DBH, total height and crown width for both species.

• Journal of Korea Planning Association
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• v.54 no.2
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• pp.33-45
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• 2019

The Legal Floor Area Ratio (L-FAR) has been used as a major urban planning tool for efficient management of land use, landscape, and density. The Developed Floor Area Ratio (D-FAR) in each parcel is realized by such physical and institutional factors as urban tissue, local characteristics, and zoning with the L-FAR. The Achieved Floor Area Ratio (A-FAR), the ratio of the D-FAR to the L-FAR, is the relationship between realized density and the intended/desired outcomes of the regulations. The A-FAR informs the efficiency of L-FAR and its effect on parcels, and is an indicator of the demands of real estate developments under the zoning regulation. This study used detailed data of each parcel's characteristics, including parcel size, road width, and the number of roads bordered by a parcel, to identify the influencing factors on A-FAR. This analysis confirmed that the parcel size has a non-linear negative effect in the residential zone but a linear positive effect on A-FAR in the commercial zone. The width of the parcel's frontage in the commercial zone has a positive effect on the value, while in the residential zone the narrower width has higher A-FAR. In Seoul, the residential zone has higher A-FAR than the commercial zone, which means that the former has a relatively higher development pressure but a lower designated L-FAR. This result reflects that Seoul's residential zone absorbs the demand of commercial uses because of the significant permitting of mixed land use and has high-density residential buildings.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.1
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• pp.44-50
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• 1993

The suspended particulate matters had been collected by a cascade impactor having 9 size fragnated stages for 2 years (Dec. 1989 to Nov. 1991) in Kyung Hee University-Suwon Campus. The particulate matters were then collected on each stage by membrane filters. The weight concentration on each stage was estimated by a microbalance and further chemical element concentrations were determined by an XRF system. The study focused on developing of a receptor model using the TTFA (target transformation factor analysis) to apportion aerosol mass with the 30 ambient data sets. Each data set consists of the 8 size-ranged subdata sets characterized by 13 element variables. Even though a couple of sources could not be identified, three to five sources were extracted from each aerosol size-range, and then 9 statistical source profiles were generated. Finally, source contribution of particulate matters on each size-range could be estimated in Suwon area.

• Journal of Mechanical Science and Technology
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• v.18 no.2
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• pp.253-261
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• 2004

A simple and effective filtering method to control the member size of an optimized structure is proposed for topology optimization. In the present approach, the original objective sensitivities are replaced with their relative values evaluated within a filtering area. By adjusting the size of the filtering area, the member size of an optimized structure or the level of its topological complexity can be controlled even within a given finite element mesh. In contrast to the checkerboard-free filter, the present filter focuses on high-frequency components of the sensitivities. Since the present filtering method does not add a penalty term to the objective function nor require additional constraints, it is not only efficient but also simple to implement. Mean compliance minimization and eigenfrequency maximization problems are considered to verify the effectiveness of the present approach.

• ETRI Journal
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• v.28 no.5
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• pp.660-663
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• 2006

In this letter, we propose a frame-size adaptive MAC protocol for high rate wireless personal area networks (WPANs). In the proposed scheme, during communication, frame error rate is periodically reported to a transmitting device and the frame size is changed according to the measured results. Thus, the channel can be more effectively utilized by adapting to variable radio conditions. Analytical results show that this scheme achieves a much higher throughput than a non-frame-size adaptive media access control protocol in high-rate WPANs.

• Journal of IKEEE
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• v.7 no.2 s.13
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• pp.260-264
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• 2003

Among many factors to affect the network performance, this paper analyses how the buffer size of NIC(Network Interface Card) can affect web server and LAN(Local Area Network). We use the ns-2 which is defacto network simulation tool to observe the changes in drop rate, throughput, RTT(Round Trip Time), effective throughput depending on varying buffer sizes. And we analyse the effect of NIC buffer size on the web traffic in Ethernet.

• Journal of the Korean Ceramic Society
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• v.35 no.10
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• pp.1085-1093
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• 1998

Amorphous alumina powder prepared by the fast calcination of aluminum trihydroxide(Al(OH)3 gibbsite) for 0.5 second at 580$^{\circ}C$ was investigated rehydration propeties. Phase composition crystal size and mor-phology surface area pore volume and pore size distribution of pesudo-boehmite and bayerite crystals changed with temperature time water/alumina ratio and particle size when amorphous alumina rehydrated with water. Phase compositions were examined with XRD and DTA and crystal sized morphologies were investigaed with SEM and TEM. Also rehydration properties of amorphous alumina were in-vestigated by measuring the surface area pore volume and pore size distribution.