• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.3
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• pp.299-309
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• 2006

In recent years, a large natural disasters have occurred due to worldwide abnormal weather and the amount of damage has been increased more resulting from high density population and a large-sized buildings of the urbanized area. In this study. we estimate the flooded area according to rainfall probability intensify and sea level in Woreong dong, Masan occurred flood damages by typhoon Maemi using SWMM, a dynamic rainfall-runoff simulation model in urban area, and then analyze the damage of flood expected area through connecting with GIS database. In result, we can predict accurately expected area of inundation according to the rainfall intensity and sea level rise through dividing the study area into sub-area and estimating a flooded area and height using SWMM. We provide also the shelter information available for urban planning and flood risk estimation by landuse in expected flood area. Further research for hazard management system construction linked with web or wireless communication technology expects to increase its application.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.41-50
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• 2010

Because mountain area covers a large proportion of entire country, the forest fire have been an important matter in disaster prevention in Korea. Estimation of damaged area after forest fire would be very important because it would be the basis to make budget or to calculate quantities in the restoration plan for the damaged area. In Korea, the damaged area from forest fire is generally surveyed using GPS. In practice, however, the estimation of damaged area from forest fire have been inaccurate in lots of case due to some problems. Korea Forest Service which is taking charge of prevention of forest fire in Korea is managing a large number of helicopters for forest service on the whole country. So, it would be possible to take snapshots of the damaged area after forest fire from the helicopter using a digital camera. This study aims to establish a suitable method to estimate damaged area after forest fire using snapshots which are taken in the air using a digital camera. So, several approaches were implemented and compared. In future, results of this study could be used in a development of a system for investigation of damages from forest fire using digital photographs.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1295-1296
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• 2007

A lot of researches about dye-sensitized solar cell (DSC) are recently being conducted. Because DSC has several advantages to pass the limits of silicon solar cells such as a low manufacturing expense, a simple manufacturing process and its transparency. But most researches on DSC are still conducted about the unit cell and laboratory-centered. That is, present researches on DSC are not practical. Therefore, researches about large area cells and modules have to be prerequisites for DSC to have the practicality. Characteristics of large area DSC are so different from those of small area DSC in aspect of fill factor and efficiency. In this study, we made an experiment on finding suitable size of DSC that has the most effective power according to the variation of active area. In detail, the experiment was conducted about the optimum ratio of length to width and we introduced the ratio of active area to non-active area to find the active area which has the best output. Because small DSC doesn‘t have the best output in comparison with total area of cell although the smaller DSC has the better efficiency. As a result, we achieved the optimum ratio of length to width of 8:3 and active area of $8cm^2$ as the optimum size for upscaling DSC.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.421-426
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• 2011

Purpose: Although the sural nerve is the most commonly used donor for autologous nerve graft, its morbidity after harvesting is sparsely investigated. The sural nerve being a sensory nerve, complications such as sensory changes in its area and neuroma can be expected. This study was designed to evaluate the donor site morbidity after sural nerve harvesting. Methods: Among the 13 cases, who underwent sural nerve harvesting between January 2004 and August 2009, 11 patients with proper follow up were included in the study. The collected data included harvested graft length, actual length of the grafted nerve, anesthetic and paresthetic area, presence of Tinel sign and symptomatic neuroma, and scar quality. Results: In 7 patients, no anesthetic area could be detected. Of the patients with a follow up period of more than 2 years, all the patients showed no anesthetic area except two cases who had a very small area of sensory deficit ($225mm^2$) on the lateral heel area, and large deficit ($4,500mm^2$) on the lateral foot aspect. The patients with a short follow up period (1~2 m) demonstrated a large anesthetic skin area ($6.760mm^2$, $12,500mm^2$). Only one patient had a Tinel sign. This patient also showed a subcutaneous neuroma, which was visible, but did not complain of discomfort during daily activities. One patient had a hypertrophic scar in the retromalleolar area, whereas the two other scars on the calf were invisible. Conclusion: After a period of 2 years the size of anesthetic skin in the lateral retromalleolar area is nearly zero. It is hypothesized that the size of sensory skin deficit may be large immediately after the operation. This area decreases over time so that after 2 years the patient does not feel any discomfort from nerve harvesting.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.855-857
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• 2001

The aim of this study was to assess the associations of some potential risk factors and occurrence of calf mortality in large-scale dairy farms. Njoro area of the Rift valley, Kenya was selected due to its potential of large-scale dairy farms, since the time of the Europeans settlers. The study was retrospective and focused on the calves dying from January 1996 through October 1998. Sample of studied population consisted of 105 calves extracted from the farm records. Data was collected using a questionnaire and were grouped into farm-level and animal-level factors. Calf mortality was 15.6% and important risk factors for calf mortality were sex of calf, season of birth, pneumonia disease, age of dam when calf was born and house type for calves. Female calve born during colder wet seasons and born to dams of 2-4.5 years of age were equally at higher risk. Calves raised in movable pens compared to those raised in permanent pens were at higher risk of mortality from pneumonia. Animal level factors were major causes of calf mortality in commercial farms used in this study and therefore details study is needed in these factors in controlling the calf mortality rates.

• Proceedings of the KSRS Conference
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• v.1
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• pp.360-363
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• 2006

The red tide related with Cochlodinium Polykrikoides bloom has been frequently occurred around the South Sea of Korea and caused the economic loss in the coastal breeding grounds. The outbreak scale was usually change by physical, biological and environmental condition at each years. Relatively large-scale red tide occurred in 1995, 1997, 1999, 2001, 2002 and 2003 through spatial scale, duration and maximum density. Compared the scale of red tide with physical condition around the South Sea, the lower coastal temperature on August around the South Sea corresponded with the large scale red tide. By serial oceanographic investigations on August in the South Sea and estimated wide area temperature information by satellite, SSTA around the South Sea and wide area was negative when the outbreak of red tide was large scale. From the results of temperature difference between surface and 30m layers, the occurrence of enormous red tide has a tendency when the temperature gradient around the seasonal thermocline was weakened. Larger Kuroshio volume transport in the upstream was also corresponded with the large scale red tide.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.239.1-239.1
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• 2011

Dye sensitized solar cells (DSC) are promising devices for inexpensive, nontoxic, transparent, and large-scale solar energy conversion. Generally thick $TiO_2$ nanoporous films act as efficient photoanodes with their large surface area for absorbing light. However, electron transport through nanoparticle networks causes the slowdown and the loss of electron transport because of a number of interparticle boundaries inside the conduction path. We have studied DSCs with precisely dimension-controlled $TiO_2$ nanotubes array as photoanode. $TiO_2$ nanotubes array is prepared by template-directed fabrication method with atomic layer deposition. Well-ordered nanotubes array provides not only large surface area for light absorbing but also direct pathway for electrons with minimalized grain boundaries. Large enlongated anatase grains in the nanotubes could enhance the conductivity of electrons, but also suppress the recombination with holes through defect sites during diffusion into the electrode. To study the effect of grain boundaries, we fabricated two kinds of nanotubes which have different grain sizes by controlling deposition conditions. And we studied electron conduction through two kinds of nanotubes with different grain structures. The solar cell performance was studied as a function of thickness and grain structures. And overall solar-to-electric energy conversion efficiencies of up to 7% were obtained.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.80-81
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• 2014

Generally significant reinforcement is used for nuclear power plant structures and may cause potential problems when concrete is poured. In particular pouring concrete into structural member joint area is more difficult than other areas since the joint area is very congested due to hooked bars, embedded plates, and other reinforcements. The purpose of this study is to solve the problem by applying high-strength(ASTM A615 Gr. 75/80) bars. In addition large-sized(#14 & #18) headed deformed bar could be used as alternative of standard hooked bars to relieve the congestion to some extent. In order to apply headed deformed bars to nuclear power plant structures effectively, the large-sized diameter bars and the high-strength bars shall be used as thick as clear cover thickness 1". Therefore, test results were obtained by taking bar size, yield strength, and clear cover thickness as variables.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1319-1327
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• 2015

As wind power farm (WPF) installations continue to grow, monitoring and controlling large-scale WPFs presents new challenges. In this paper, a hierarchical network architecture is proposed in order to provide remote monitoring and control of large-scale WPFs. The network architecture consists of three levels, including the WPF comprised of wind turbines and meteorological towers, local control center (LCC) responsible for remote monitoring and control of wind turbines, and a central control center (CCC) that offers data collection and aggregation of many WPFs. Different scenarios are considered in order to evaluate the performance of the WPF communications network with its hierarchical architecture. The communications network within the WPF is regarded as the local area network (LAN) while the communication among the LCCs and the CCC happens through a wide area network (WAN). We develop a communications network model based on an OPNET modeler, and the network performance is evaluated with respect to the link bandwidth and the end-to-end delay measured for various applications. As a result, this work contributes to the design of communications networks for large-scale WPFs.

• The Journal of the Korean dental association
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• v.12 no.10
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• pp.747-751
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• 1974

The authors had a case of large periodontal cyst treated by Apicoectomies in 32 year old, Korean female. 1. A large periodontal cyst revealed big size in Maxilla, left side. 2. The authors have treated the periodontal cyst by means of the apicoectomies of the involved left lateral incisor, canine, 1st premolar and 2nd premolar teeth, maxilla. 3. Radiographic examination revealed a large radiolucent lesion 2.7 3.7cm in diameter, in the midline area, with involvement of the lateral incisor, canine, 1st premolar and 2nd premolar teeth, maxilla.