• Journal of Korea Water Resources Association
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• v.50 no.6
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• pp.373-386
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• 2017

This study simulated water quality item and flow rate of subbasin for Saemangeum watershed using Soil and Water Assessment Tool (SWAT) model and Environmental Fluid Dynamics Code (EFDC) model which simulate hydraulic and water quality in three-dimensions. The simulated values corresponded to observed value well. The result of simulation for floodgate operations at the M3 and M5 points, it exceeds water quality standard and at the M3 and D3 points, change of range for concentration is too wide, and upstream of Saemangeum reservoir is sensitive to inflow flow rate. Compared to the annual average concentration for observed station according to the discharge conditions, improvement of water quality for upstream was apparently compared to the downstream. Range of influence for change of water quality presented that maximum discharge condition, the influence range is 22 km in the direction of the Saemangeum downstream from the Mankyung bridge, and 15 km in the downstream direction of saemangeum in the Dongjin bridge. This study result demonstrated that floodgate operating at upstream has significant influence on water quality management of Saemangeum reservoir and it needs to be considered in plans of water quality management for Floodgate operation on Saemangeum reservoir.

• Journal of Cadastre & Land InformatiX
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• v.47 no.1
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• pp.143-160
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• 2017

Since officially assessed land price system was introduced, it has functioned as the criterion for establishing and implementing real estate policies. However, there is a controversial issue about the adequacy of the officially assessed land price system. The problem is that it is difficult to establish a statistical model due to too many land characteristics. Also, local economy, macroeconomic environments and development plans are not reflected in the land price evaluation model. Considering longitudinal and cross-sectional variables, a two-way error component panel model was used in this study. This analysis model includes variables reflecting land characteristics, macroeconomic volatility, and development project. The Paju LCD Industrial Complex was selected as a analysis area and an empirical analysis was performed. According to the analysis, the number of significant land characteristic variables were 14(31%) under 5% significance level. Macroeconomic volatility has had an influence on the land price and year variable reflecting development project has consistently been significant since the industrial complex was designated. Therefore, this study suggests that the land price evaluation model should be improved by simplifying land characteristic variables and including macroeconomic and regional economic variables.

• The Korean Journal of Ecology
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• v.24 no.2
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• pp.101-109
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• 2001

We created an environmental forest on the basis of ecological design around the incineration plant of Jindo Engineering and Construction Co., Ltd., which is located in Jeongwang-dong, Siheung-si, Kyunggi-do. To get ecological information of this site, physico-chemical properties of soil on salt marsh, which is located close to the syudy site and of forest soil transported from other sites for ecological restoration were analyzed. Texture of salt marsh and transported soils were loam and sandy loam, respectively. pH, organic matter, T-N, available P, and exchangeable K and Na contents of salt marsh and transported forest soils were 6.7 and 5.4, 4.1 and 0.4%, 1.0 and 0.3mg/g, 46.7 and 6.8ppm, 521 and 207ppm, and 3.8 and 0.5mg/g, respectively. Introduced plants were selected among the dominant species of forests and the species composing the potential natural vegetation around the present study site. Those plants were selected again by considering the tolerances to air pollution and to salt, and their availability. Selected trees were Pinus thunbergii, Sophora japonica, Celtis sinensis, Quercus aliena, Q. serrata, Q. dentata, and Q. acutissima. Selected sub-trees were Albizzia julibrissin, Koelreuteria poniculata, and Styrax japonica and shrubs were Rhododendron yedoense var. poukhanense, R. mucronulatum, Callicarpa japonica, Euonymus alatus, E. japonica, and R. schlippenbachii. On the other hand, introduction of herbs was not considered except for Liriope platyphylla, which was ornamentally planted in one site. Planting bed of mound type was adopted to provide the fine drainage system. Mound was designed to furnish litter, A, B, and C layers simuating the profile of forest soil. Slope of mound was mulched by rice straw of 2cm in thickness to prevent for sliding of litter and soil in cases of strong wind or heavy rain. Height of mound was designed to secure more than 1 m by combining A and B layers. Narrow zones, in which mound with stable slope degree cannot be prepared, was designed to equip the standard soil depth with the introduction of stone for supporting. On the other hand, plants with shallow root system were arranged in some zones, in which satisfactory soil depth cannot be ensured. Plants were arranged in the order of tree, sub-tree, and shrub from center to edge on the mound to make a mature forest of a dome shape in the future. Dispersion of plants was designed to be random pattern rather than clumped one. Problems on creation of the environmental forest by such ecological design were found to be management or inspection by non-specialized project operators and inspecting officers, and regulations for construction without ecological background. Alternative plans to solve such problems were suggested.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3B
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• pp.277-284
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• 2011

The limitations of existing Markov chain model for reproducing extreme rainfalls are a known problem, and the problems have increased the uncertainties in establishing water resources plans. Especially, it is very difficult to secure reliability of water resources structures because the design rainfall through the existing Markov chain model are significantly underestimated. In this regard, aims of this study were to develop a new daily rainfall simulation model which is able to reproduce both mean and high order moments such as variance and skewness using a piecewise Kernel-Pareto distribution. The proposed methods were applied to summer and fall season rainfall at three stations in Han river watershed in Korea. The proposed Kernel-Pareto distribution based Markov chain model has been shown to perform well at reproducing most of statistics such as mean, standard deviation and skewness while the existing Gamma distribution based Markov chain model generally fails to reproduce high order moments. It was also confirmed that the proposed model can more effectively reproduce low order moments such as mean and median as well as underlying distribution of daily rainfall series by modeling extreme rainfall separately.

• Journal of the Korean Society of Radiology
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• v.9 no.7
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• pp.449-457
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• 2015

In this study, to evaluate the usefulness of the treatment plan of tomotherapy and volumetric modulated arc therapy (VMAT) in the radiotherapy for prostate cancer, the absorbed dose, dose volume histogram (DVH), treatment efficiency, and the results of dose verification accuracy using MapCHECK2 were compared and analyzed. Of the prostate cancer patients who underwent tomotherapy treatment in the Radiologic Oncology of H University Hospital between July 2014 and December 2014, 12 patients were randomly selected. As a result of analyzing the absorbed dose and DVH, both radiologic treatment plans showed slight differences in the treatment of the cancer tissues and the bladder, but the difference was in the error range of -5% to +3%, and did not exceed the side effect guideline or the tolerance dose limit. VMAT showed higher treatment efficiency than tomotherapy with a 2.5 times shorter treatment time and a 10.3 times less monitor unit (MU). Both showed 95% or higher dose accuracy satisfying the standard. VMAT showed 2.3% higher efficiency than tomotherapy. In both tomotherapy and VMAT, appropriate doses were absorbed for cancer tissues, and did not exceed the tolerance dose for normal tissues showing no significant difference in dose distribution. However, considering the shorter treatment time, lower total MU, and better treatment efficiency and dose verification accuracy, VMAT may be more useful than tomotherapy in cancer treatments.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.7
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• pp.110-114
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• 2017

Because the arm can't be sutured due to fracture during a elbow CT scan, a CT scan is proceeded in a state of abdomen and L-spire are overlapped which beam hardening artifact is done many times, and it often lowers the quality of elbow CT images. So there are many difficulties in reading and due to increase in radiation dose from it, the number of patient's exposure keeps increasing. In this research, it plans to improve the quality of the images by avoiding overlap with abdomen, and increasing the number of photon overlapped with lung field which the line attenuation is relatively small. The way of experiment is based on patient's right elbow and place him as head first position, then place his elbow at L2-3 level in supine position, turn about 30 degrees to the left in non-control breathing and in supine position, and compared with full inspiration after overlapping with lung. After figuring out the average value and standard deviation data using Image J program 5 times each for 16, 128 channels, the evaluation is proceeded by measuring each of CNR, MSR are statistically analyzed using SPSS program. Therefore, through positioning and inspiration during elbow CT scan, the way of inspection minimized the exposure radiation dose, and seems to be meaningful in a way to improve the quality of the images.

• Journal of Korean Home Economics Education Association
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• v.31 no.2
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• pp.113-135
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• 2019

The purpose of this study was to analyze the characteristics reflected in the 2015 revised home economics curriculum for the key competencies presented in the OECD education 2030 project. The results indicate that first, in general, about 46.5% of the competencies could be classified into the skill, attitude and value category; 17% into the learning concept framework category; 24.2% into the competency development cycle category; and 12.5% into the complex competency category. Overall, the competencies of the OECD learning framework are found to be reflected primarily in the achievement standards(59%), followed by characteristics(16.1%), teaching-learning and assessments orientation(9.4%), content system(8%), and goals(7.6%). Second, the key competencies were reflected in the middle school curriculum, more often in the descending order of action, problem-solving, communication, respect, creative thinking, conflict resolution, empathy, critical thinking, self-regulation, and student agency. In the high school curriculum, the competencies were reflected more often in the descending order of action, empathy, problem-solving, anticipation, global competence, self-regulation, student agency, literacy for sustainable development, reflection, and critical thinking. Third, the heat map shows that the competencies corresponding to the third and fourth levels are most frequently reflected in the curriculum. Therefore, it is advisable to develop effective plans to execute and support the reflection of key competencies in the curriculum. Through this study, home economics educators are expected to understand the inter-connectivity between the key competencies emphasized by the OECD learning framework and the competencies of home economics as a practical subject, and to scrutinize how to help individual students develop their overall competencies and be prepared for the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.138-147
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• 2020

The construction field is one of the most representative job creation businesses, but it has been pointed out that the overall quality of the jobs is low because of the nature of the order-made production industry, such as unstable employment structure, aging workforce, etc.. Accordingly, the government plans to implement the "prevailing wage system" that guarantees a minimum wage for construction site workers. In reality, however, only a market wage could be used for a construction cost estimation because there was no standard for the prevailing wage. A comparative analysis of the prevailing wage and market wage was performed. This paper proposes a framework for estimating the reasonable prevailing wage in the construction industry. The results showed that the prevailing wage was estimated to be 4.7% lower than the market wage when the proposed framework is applied to the carpenters' case. This suggests that the proposed model could be used as an alternative for market wage considering the original purpose of the prevailing wage. This study will construct the basic data for scientific analysis on the wage, and finally, help estimate the reliable prevailing wage in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.490-498
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• 2017

The purpose of this study was to investigate how many kindergarten parents use after-school programs and specialization activities and to suggest effective policy improvement plans based on the results. After 693 parents were interviewed by the investigators, the collected data were presented by calculating the percentages, averages, and standard deviations. First of all, the results of after-school are presented. First, about 38.2% of the surveyed parents spent additional expenses to use after - school program, and the average of additional costs was about 62,850 won. When the cost burden and satisfaction were evaluated as 5 points, it was rated as normal. Second, the main reason for participating in the after-school program was both parents were working, followed by the parents' wishes for their children to spend time with their friends. Next, the results for specialization activities at kindergartens are presented. First, the proportion of children using after-school specialization activities was 68.2%, of which 79% were expenditures, the number of activities was 2.69, and the average cost was 83,540 won. Second, the most preferred after-school specialization activity by age group was English, and the most common reason for this was that the children liked to participate. Improvement of the educational contents suggested as the most important thing to improve after-school specialization activities. Lastly, the results showed that after-school specialization activities reduced parents' spending on private education. On the basis of the results, some discussions are presented included the development after-school programs focusing on the different needs of children and parents accordingly.

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.173-182
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• 2012

Entry and exits of the rest area are sections where designed speed can be rapidly change and also a weak traffic safety section. In addition, two tasks can be performed simultaneously at entry of the rest area, particularly searching for deceleration and parking spaces/parking sides etc. Thus, design criteria is required in order to procure the stability of accessed vehicle. In case of Korea, geometric structure design criteria of entry facilities, such as toll-gate, interchange, junction etc was established. However there are no presence in a detailed standards for geometric structure of the rest area which affiliated road facilities. In this study, Derive problems in regards to the entry of geometric structure of resting areas by utilizing a sight survey and an investigation research of traffic accidents. The survey was targeting 135 general service areas. After Classifying the design section of resting areas' entry as well as derive design elements on each section, a speed measurement by targeting entry of rest areas and car behavior surveys were performed, then each element's minimum standard was derived through the analyses. According to the speeds at the starting/end point of entrance connector road, the minimum length of the entrance connector road is decided as 40m using Slowing-down length formula and based on the driving pattern, the range of the junction setting angle of the entrance connector road is defined as $12^{\circ}{\sim}17^{\circ}$. Suggest improvement plans for existing rest areas that can be applied realistically. This should be corresponded to the standards of entry and exit of developed rest areas.