• Journal of Korea Water Resources Association
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• v.38 no.4 s.153
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• pp.301-311
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• 2005

The purpose of this study is to assess the quantitative effect of stream discharge due to land use changes. The upstream watershed of Pyeongtaek gauging station of Anseong-cheon ($592.6\;km^2$) was adopted. To accomplish the purpose, firstly, trace land use changes for the selected watershed which have some changes of land use by using Landsat images of 1986 and 1999 of the watershed and secondly, analyse the quantitative effect of stream discharge due to land use changes by applying GIS- based distributed hydrologic model KIMSTORM. The model was calibrated and verified at 2 locations (Pyeongtaek and Gongdo) by comparing observed with simulated discharge results for 7 storm events from 1998 to 2003. Model output was designed to provide information of land use impact on runoff components in the watershed and the sensitivity of impact level of each land use category on storm runoff. Land use impact was evaluated with the land use data sets for 1986 and 1999 for the same rainfall condition (160.5 mm). Area decrease of 4.8 percent of forest and 4.0 percent of paddy field during 13 years (1986 - 1999) within the watershed caused a 30.3 percent increase of peak runoff and a 9.3 percent increase of runoff volume.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.4
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• pp.9-17
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• 2013

This paper describes an experimental program to investigate the shear behavior of insulated concrete sandwich panels (CSPs) with different types of GFRP shear connector. The study included testing of 13 insulated CSP specimens with two types of surface conditions for extruded polystyrene (XPS) insulation and various shapes of shear connectors. All specimens were loaded in direct shear by means of push-out and were consist of three concrete panels, two insulation layer and four rows of GFRP shear connectors. Load-relative slip between concrete panel and insulation response of CSP specimens has been established through push-out shear test. Test results indicate that the surface condition of insulation has a significant effect on the bond strength between concrete panel and insulation. The specimen used XPS foam with 10mm deep slot shows higher bond strength than those used XPS foam with meshed surface. Corrugated GFRP shear connectors show equivalent strength to grid GFRP shear connectors. Cross-sectional area and embedded length of shear connector have a notable effect on overall response and inplane shear strength of the CSP specimens.

• Journal of radiological science and technology
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• v.8 no.2
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• pp.21-28
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• 1985

We serveyed the actual condition of business of the departments of radiology of 45 health conters (except 3) in the area of Seoul, Kyungki and Inchon from March, 1984 to November, 1984. The results are summarized as follows : 1. T.O. of the radiologic technologist is three persons in each health center of Seoul area, and one person in each one of Kyungki and Inchon area. P.O. is 2-5 persons in Seoul area, 1-2 persons in Kyungki or Inchon area. 2. The number of all the radiologic technologists employed now is 75 persons, and among all of them, when analized by position class 7th is 54.7%, class 8th 28.0%, class 9th is 13.3%, and class 6th is 2.7%, and by sex, female is 68.0%, male is 32.0%, by educational background, for the most part, junior college graduates come to 73.3%, by age group 60% of them is in their twenties, 16.0% is in their thirties and forties, 8.0% is in their fifties, and by career after certificate 60% have the career of 1-5 years, 13.3% have the one of 6-7 years or mor than 21 years, and 6.7% have the one of 11-15 years of 16-20 years. 3. All the diagnostic x-ray equipment being kept is 62, and among them flxing equipment is 71.0%, portable equipment is 29.0% and by rating of X-ray equipment, maximum tube current 100 mA is 46.8%, maximum KV 100KVP is 72.6%, the most part. 4. Photofluorographic camera and hood are equipped in every health center. While, as to the radiographic cassettes, $14{\times}14"$ cassetts are equipped in every health center, but cassettes of other sizes are in half of them. 5. Bucky's table is equipped in 11.9% health centers, the automatic processor is in 21.4%, the photofluorographic film changer is 9.5%, the grid is 73.8%, the protective apron is in 88.1%, and the protective glove is in 57.1% health centers. 6. The number of the people who got the x-ray examination for one year (by the year 1989) is the most, 1,000-6,000 in direct radiography of the chest, or 15,0001-45,000 in the health centers of Seoul area, 5,000-20,000 in Kyungki and Inchon area in photofluorography of the chest. Moreover, other radiographies are being taken extremely limitedly in all health centers. 7. In processing types of x-ray film, automatic processing is used in 9 health centers (21.4%), manual tank processing is in 30 (71.4%), and manual tray processing in 3 (7.2%). 8. As for collimation of x-ray exposure field, "continual using restricted by a subject size" has the most part, 78.6% "restricted using at every radiography" has 19%, and the case of "never considered" has 2.4% response. 9. As for the dosimeter used for radiation control, film badge (35.7%) and pocket dosimeter (26.2%) are used, and in 38.1% health centers the dosimeter is not equipped at all. Consideration of the previous radiation exposure is being done in only one health center. 10. Reading of radiographs is mainly depended on the radiologists electively (45.2%) or on the genral practitioners(45.2%).

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.1-15
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• 2020

This study was designed to come up with a way of managing a cultural landscape forest by conducting research on the vegetation structure and growth characteristics. This study's target site, which was 45,201㎡ in size, was Pinus densiflora forest for Sugumagi placed at the entrance of Unmun Temple, Sinwon-ri, Unmun-myeon, and Cheongdo-gun in the southernmost part of Gyeongsangbuk-do, Korea. Sugumagi means the water of the valley flows far away, and where no downstream is visible according to feng shui. The historical sources of the Sugumagi Pinus densiflora forest at the entrance of Unmun Temple isn't clear. It waw only found at that location. The Pinus densiflora forest at the entrance of Unmun Temple is located in the waterway in terms of Feng Shui. The present condition of growth was investigated through a grid surveys of 98 trees and Pinus densiflora growth. As a result of the analysis of growth status, Pinus densiflora, Larix leptolepis, Zelkova serrata, Celtis sinensis, and Rhus javanica were distributed in the conopy layer, and 28 species including Ailanthus altissima were grown in the understroy layer, and 92 species, including Ampelopsis brevipedunculata, in the shrub layer. The plant community structure was divided into low, medium and high-density Pinus densiflora forests in the study area, based on the number in the conopy layer and the grade of and the trees analyzed. As a result of the analysis, the Pinus densiflora dominated the low, medium and high-density Pinus densiflora forests, and there were no competitive species. The relative dominance of the low-density Pinus densiflora forests was 46.9% on average, medium-density was 62.6% and 50.2% was found in high-density. The mean species diversity of Shannon in the low-density study was 0.7055, medium-density study was 0.8966 and the average species diversity of Shannon in the high-density study was 0.8317. The analysis of the age and growth of 25 sample trees in the Sugumagi Pinus densiflora forest shows that the distribution of the chest diameter (DBH) of the sample Pinus densiflora is 38 to 77cm with the average chest diameter being 61.1cm. The age was 84-161 years and the average was 114 years. In the Pinus densiflora forest, most(670,659, or 98.3%) of the tree trunk wound was collected for rosins during the Japanese colonia Era, Of the total 670, 659 were Pinus densiflora, 98.3% of the total. 394 were surgically repaired in 2005. For the preservation of the Sugumagi Pinus densiflora forest, dead trees should be replaced with substitute trees appropriate to the middle and south topography. It is demanded that foreign species such as Larix leptolepis in the research area should be removed and Pinus densiflora that underwent surgical operations should be regularly sterilized. It is also emphasized that the management of insecticide is important.

• Journal of Korean Society of Transportation
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• v.19 no.1
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• pp.101-114
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• 2001

Transportation enterprises should maintain constant and qualitative operation. Thus, in short period, transportation enterprises don't change supply in accordance with demand. In the result, transportation enterprises don't reduce operation in spite of management deficit at will. In freight transportation type, less-than-truckload(LTL) has more relation with above transportation feature than truckload(TL) does. Because freight transportation supply of TL is more flexible than that of LTL in correspondence of freight transportation demand. Relating to above mention, it appears that shortage of road and freight terminal of LTL is larger than that of TL. Especially in road and freight terminal comparison, shortage of freight terminal is larger than that of road. Shortage of road is the largest in 1990, and improved after-ward. But shortage of freight terminal is serious lately. So freight terminal needs more expansion than road, and shows better investment condition than road. Freight terminal expansion brings road expansion in LTL, on the contrary, freight terminal expansion substitutes freight terminal for road in TL. In transportation revenue, freight terminal's contribution to LTL is larger than that to TL. However, when we adjust quasi-fixed factor - road and freight terminal - to optimal level in the long run, in TL, diseconomies of scale becomes large, but in LTL, economies of scale becomes large. Consequently, it is necessary for TL to make counterplans to activate management of small size enterprises and owner drivers. And LTL should make use of economies of scale by solving the problem, such as nonprofit route, excess of rental freight handling of office, insufficiency of freight terminal, shortage of driver, and unpreparedness of freight insurance.

• Journal of radiological science and technology
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• v.31 no.4
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• pp.401-406
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• 2008

The aim of this study is to evaluate contra-lateral breast (CLB) surface dose in Field-in-Field (FIF) technique for breast conserving surgery patients. For evaluation of surface dose in FIF technique, we have compared with other techniques, which were open fields (Open), metal wedge (MW), and enhanced dynamic wedge (EDW) techniques under same geometrical condition and prescribed dose. The three dimensional treatment planning system was used for dose optimization. For the verification of dose calculation, measurements using MOSFET detectors with Anderson Rando phantom were performed. The measured points for four different techniques were at the depth of 0cm (epidermis) and 0.5cm bolus (dermis), and spacing toward 2cm, 4cm, 6cm, 8cm, 10cm apart from the edge of tangential medial beam. The dose calculations were done in 0.25cm grid resolution by modified Batho method for inhomogeneity correction. In the planning results, the surface doses were differentiated in the range of $19.6{\sim}36.9%$, $33.2{\sim}138.2%$ for MW, $1.0{\sim}7.9%$, $1.6{\sim}37.4%$ for EDW, and for FIF at the depth of epidermis and dermis as compared to Open respectively. In the measurements, the surface doses were differentiated in the range of $11.1{\sim}71%$, $22.9{\sim}161%$ for MW, $4.1{\sim}15.5%$, $8.2{\sim}37.9%$ for EDW, and 4.9% for FIF at the depth of epidermis and dermis as compared to Open respectively. The surface doses were considered as underestimating in the planning calculation as compared to the measurement with MOSFET detectors. Was concluded as the lowest one among the techniques, even if it was compared with Open method. Our conclusion could be stated that the FIF technique could make the optimum dose distribution in Breast target, while effectively reduce the probability of secondary carcinogenesis due to undesirable scattered radiation to contra-lateral breast.

• Journal of Environmental Impact Assessment
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• v.30 no.1
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• pp.13-23
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• 2021

In this study, we performed a Random Walker analysis to predict the Major Movement Paths of otters. The scope of the research was a simulation analysis with a radius of 7.5 km set as the final range centered on the Ansim-wetland in Daegu City, and a field survey was used to verify the model. The number of virtual otters was set to 1,000, the number of moving steps was set to 1,000 steps per grid, and simulations were performed on a total of 841 grids. As a result of the analysis, an average of 147.6 objects arrived at the boundary point under the condition of an interval of 50 m. As a result of the simulation verification, 8 points (13.1%) were found in the area where the movement probability was very high, and 9 points (14.8%) were found in the area where the movement probability was high. On the other hand, in areas with low movement paths probabilities, there were 8 points (13.1%) in low areas and 4 points (6.6%) in very low areas. Simulation verification results In areas with high otter values, the actual otter format probability was particularly high. In addition, as a result of investigating the correlation with the otter appearance point according to the unit area of the evaluation star of the movement probability, it seems that 6.8 traces were found per unit area in the area where the movement probability is the highest. In areas where the probability of movement is low, analysis was performed at 0.1 points. On the side where otters use the major movement paths of the river area, the normal level was exceeded, and as a result, in the area, 23 (63.9%), many form traces were found, along the major movement paths of the simulation. It turned out that the actual otter inhabits. The EN-Simulator analysis can predict how spatial properties affect the likelihood of major movement paths selection, and the analytical values are used to utilize additional habitats within the major movement paths. It is judged that it can be used as basic data such as to grasp the danger area of road kill in advance and prevent it.

• Atmosphere
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• v.31 no.2
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• pp.229-240
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• 2021

The Global Ocean Data Assimilation and Prediction System (GODAPS) in operation at the KMA (Korea Meteorological Administration) is introduced. GODAPS consists of ocean model, ice model, and 3-d variational ocean data assimilation system. GODAPS assimilates conventional and satellite observations for sea surface temperature and height, observations of sea-ice concentration, as well as temperature and salinity profiles for the ocean using a 24-hour data assimilation window. It finally produces ocean analysis fields with a resolution of 0.25 ORCA (tripolar) grid and 75-layer in depth. This analysis is used for providing a boundary condition for the atmospheric model of the KMA Global Seasonal Forecasting System version 5 (GloSea5) in addition to monitoring on the global ocean and ice. For the purpose of evaluating the quality of ocean analysis produced by GODAPS, a one-year data assimilation experiment was performed. Assimilation of global observing system in GODAPS results in producing improved analysis and forecast fields with reduced error in terms of RMSE of innovation and analysis increment. In addition, comparison with an unassimilated experiment shows a mostly positive impact, especially over the region with large oceanic variability.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.148-160
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• 2012

The main purpose of this paper is to deliver a climate analysis and evaluation method based on GIS by using airborne LiDAR data and Biotop type map and to provide spatial information of climate analysis and evaluation based on Biotop type Map. At first stage, the area, slope, slope length, surface, wind corridor function and width, and obstacle factors were analyzed to obtain cold/fresh air production and wind corridor evaluation. In addition, climate evaluation was derived from those two results in the second stage. Airborne LiDAR data are useful in wind corridor analysis during the study. Correlation analysis results show that ColdAir_GRD grade was highly correlated with Surface_GRD (-0.967461139) and WindCorridor_ GRD was highly correlated with Function_GRD (-0.883883476) and Obstacle_GRD (-0.834057656). Climate Evaluation GRID was highly correlated with WindCorridor_GRD (0.927554516) than ColdAir_GRD (0.855051646). Visual validations of climate analysis and evaluation results were performed by using aerial ortho-photo image, which shows that the climate evaluation results were well related with in-situ condition. At the end, we applied climate analysis and evaluation by using Biotop map and airborne LiDAR data in Gwangmyung-Shiheung City, candidate for the Bogeumjari Housing District. The results show that the aerial percentile of the 1st Grade is 18.5%, 2nd Grade is 18.2%, 3rd Grade is 30.7%, 4th Grade is 25.2%, and 5th Grade is 7.4%. This study process provided both the spatial analysis and evaluation of climate information and statistics on behalf of each Biotop type.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.