• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.186-193
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• 1996

Several chitosan beads were prepared by W/O emulsion and capillary extrusion methods. The surface structures were observed through SEM pictures, the surface areas were determined by BET method, the available amine contents were measured by picric acid titration method, and the results were correlated each other. The beads from W/O emulsion method were smaller in size but had higher hardness, surface area, and available amine contents than the ones from capillary extrusion method. Moreover, the surface area, available amine contents, apparent density and the hardness showed large differences according to the drying processes. As compared between the solvent dehydration and the freeze drying technique in W/O emulsion method, the former showed higher surface area, higher available amine contents and hardness than the latter. SEM pictures revealed that in case of solvent dehydration method, very small pores existed, whereas in case of freeze drying method, cell-like pores existed on the surface. The results of picric acid titration showed that the beads dried by solvent dehydration method were 10 times higher in amine contents than those from freeze drying method, and the amount of amine contents were increased as the surface area was increased. After fluorescamine was reacted with chitosan beads, the fluorescence labeled beads were observed through fluorescence microscope. The results showed that most of primary amine existed on the surface of beads and pores.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.50-55
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• 2004

Performance predictions of the propulsion system were conducted for a 900㎏ class Canard Rotor/Wing vehicle. The main components of the propulsion system are turbojet engine, exhaust ducts and nozzles. The internal flow of the duct was considered as one-dimensional, compressible and viscous flow. Adequate governing equations including centrifugal force effect were applied to the analysis of the duct flows. Results such as available power, available thrust, engine throttle, mass flow rates, rotor RPM and cruise nozzle area were presented for rotary-wing mode and transition mode.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.303-309
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• 2000

Seismic reflection method is applied to detect shallow location of limestone in Chechon area. The data using hammer source is compared with that of weight drop. Small size hammer and weight-drop are used as energy source and 100Hz geophones are used for data aquisition. Data processing is conducted utilizing the available processing technique of "Geobit", which is seismic data processing software developed by KIGAM. The result of above data processing, the velocity of topsoil layer is 1,250m/sec. The velocity of this area is higher than other area because loading trucks pass this area and make this layer compact. And in limestone area, hammer is proposed to energy source instead of weight drop because the energy propagates the layer very well.

• Journal of the Korean Institute of Educational Facilities
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• v.23 no.5
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• pp.3-10
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• 2016

The purpose of this study is to provide a basis for planning of school foodservice facilities to operate with hygiene and efficiency corresponding a decrease of the number of students. This study analyzes the composition of space for foodservice facilities categorizing by the functions which are preparation area, cooking area, cleaning area, storage, and worker's room on elementary, middle and high school in Seoul Metropolitan city since 2009 that the Seoul School Health Promotion Center published a manual for school foodservice facilities. The calculation can be a basis for school planners and the general schools to use available area in each school and can manage the school usage plan appropriately. The number of students in each school has been regarded as the space planning element, but the number of students would considered with using the specific area and time.

• The Korean Journal of Ecology
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• v.12 no.4
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• pp.285-295
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• 1989

This report is results of an investigation on the secondary succession and species diversity of the burned area. Fifty hectares of pine forest was burned by the crown fire of the spring (April 6) 1986. The results obtained from spring 1989 were summarized as follows: In the burned area , site and unburned area (U), the vascular plant fo 69 kinds, 49 kinds and 24 kinds were lsted respectively. The life form spectrum of burned area was H---e type, which is common type in most burned area and that unburned area, H---e type. The species diversity (H)and evenness index (e) of burned area (, site) were H=2.51, 1.65 and e=0.59, 0.44 and those of unburned area (U) were H=1.28 and e=0.40. The similarity index was the value of 0.594 in - and 0.236 in -U site. The similarity between and site was greater than between site and U site, and that between and U-site, The dominance index (c) of , and U-site was 0.16, 0.39 and 0.42 respectively. The succession degree (DS) of , and U-site was 244.0, 227.6 and 854.4 respectively. Soil pH, available phosphorous, and exchangeable potassium in the burned area were higher than those in the unburned area, and total nitrogen, organic carbon, and C/N ratio in the burned area were higher than those in the unburned area, and organic matter in the burned area was higher than that in the unburned area.

• Journal of Environmental Science International
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• v.15 no.5
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• pp.417-430
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• 2006

We focused on improvement in simulation of wind fields for the complex coastal area. Local Analysis and Prediction System(LAPS) was used as a data assimilation method to improve initial conditions. Case studies of different LAPS inputs were performed to compare improvement of wind fields. Five cases have been employed : I) non data assimilation, II) all available data, III) AWS, buoy, QuikSCAT, IV) AWS, buoy, wind profiler, V) AWS, buoy, AMEDAS. Data assimilation can supplement insufficiency of the mesoscale model which does not represent detailed terrain effect and small scale atmospheric flow fields. Result assimilated all available data showed a good agreement to the observations rather than other cases and estimated veil the local meteorological characteristics including sea breeze and up-slope winds. Result using wind profiler data was the next best thing. This implies that data assimilation with many high-resolution sounding data could contribute to the improvements of good initial condition in the complex coastal area. As a result, these indicated that effective data assimilation process and application of the selective LAPS inputs played an important role in simulating wind fields accurately in a complex area.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.21-24
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• 2002

Many methods are available to measure leaf area index(LAI) directly and are variations of either Leaf area index(LAI) and leaf angle distribution are widely used indices of canopy structure that are difficult to measure directly. Direct measurements of canopy structure are tedious and labor intensive in small canopies and nearly impossible in large forest canopies. This study introduced fundamental theories in LAI measurements and applied that for several crops.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.420-421
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• 2015

Recently construction of new transmission line is getting harder because of social hostility to transmission tower. Howevere, load is converged in metropolitan area and power plants near this area are old and life of generator will end soon. Therefore, power to supply load in this area should be transmitted from east coast area and southern area. For these reasons, securement of transmission capacity without new transmission line construction is important. In this paper, effect of one circuit AC line change to DC transmission at the same transmission tower on the system available transfer capacity is analyzed.

• Management & Information Systems Review
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• v.21
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• pp.189-208
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• 2007

This study was designed to find what impacts store attributes and personal characteristics have had on customer loyalty to beauty shops. Participants were 283 men and women who had experienced services in beauty shops and selected from the Metropolitan area, Busan, Gyeongbuk area, Gyeongnam area, Chungcheong area, and other area. In conclusion, technical factor and lifestyle have had the greatest impact on customer loyalty to beauty shops. In beauty market faced with keen competition, the way to meet customers' needs is to run a distinguished beauty shop with distinct beauty techniques in consideration of individual lifestyle. This will help raise customer loyalty to beauty shops. This study has the important implication that personal characteristics as well as store attributes has been proved to be essential for increasing customer loyalty to beauty shops. I hope that future studies will continue to examine different marketing factors by different beauty shops, with additional analysis on the details, contributing to make a marketing strategy available for beauty shop owners.

• Journal of Environmental Science International
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• v.11 no.7
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• pp.621-626
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• 2002

Depth-area-duration(DAD) relations are important to hydrological plans and designs for the water resources as well as the flood defence. And these relations have been still in analysis and use today because they can be applied to readily available data. In this paper, rational and consistent DAD models were developed using the multiple regression analysis and basic relationships of area ratio-runoff volume about heavy rainfall occurring in the Im-Jin river basin, 1999. In addition, revised DAD models and curves that can convert a maximum point rainfall to mean area rainfall were developed and evaluated. As results, these models seem to have predictive value in order to plan and design hydrological structures of flood defence in the Im-Jin river basin.