• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.4
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• pp.43-58
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• 2015

The greenhouse gas emission caused by rapid economic growth and population is increasing in Korea. Also, climate change from greenhouse gases emission is accelerated. IPCC(Intergovernmental Panel on Climate Change) report projects an increase of greenhouse gas emissions by 90% from the year 2000 to 2030(SRES, 2000). Within this context, establishing countermeasures on climate adaptation and mitigation is becoming increasingly important to reduce the negative effect of climate change at a global level. Along with global efforts to tackle climate change, Korean government has incorporated 'Low Carbon Green Growth'strategies into its national policy agenda. Local governments have also conducted a number of studies to devise plans for environmentally friendly and sustainable city development. In this paper, the land-use equilibrium model, which reflects economic and geographical characteristics, is used to analyze the change in residential land use and population density. The target area for study is Jeju island in Korea. With an application of land use equilibrium model, it derived three types of scenarios of the land use change: (1) dispersion scenario-reflecting present-day conditions (2) adaptation scenario-applying adaptation measures to climate change and (3) combined scenario-integrating both adaptation and mitigation measures in model to climate change. By applying dispersion to combined scenario, the general trend shows a downward shift in population density. Subsequently, energy consumption and expected cost associated with casualties were calculated on the basis of the findings of respective scenario. The results show a descending trend in energy consumption and expected casualtie. Therefore, understanding for residential land use and population density of each scenario that analyzed land use equilibrium model in the study is expected to devise a environmental city plan for climate change stabilization and climate adaptation and mitigation.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.359-367
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• 2012

This study was to evaluate the influence of dental caries prevention-related concerned and perceived in Korean adults and oral health behavior of their first child if they had children. A cross-sectional study in 1,014 adults over 19 years old were conducted in Korean adults, asked to answer a computer-assisted telephone interview regarding their oral health-related knowledge, behavior, concerned of caries prevention and child's behaviors such as frequencies of tooth brushing, chewing the xylitol gum and dental checkup. The statistical analysis was done by using the SPSS 19.0 program (IBM Co., Armonk, NY, USA). Awareness of caries prevention in the female than male, 40~49 years old age group was higher. Parents of school-age children were higher level of awareness of the dental caries prevention than other group. As knowledge and behavior of dental caries prevention were higher, the child's conduct regular oral health checkups, fluoride topical application and dental sealant was significantly higher. The higher the concerned of caries preventive, the intention of oral health behaviors and child's oral health behaviors was more increased. Awareness of caries prevention had effect on the perception of the impact of the child's oral health behaviors.

• Journal of Intelligence and Information Systems
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• v.22 no.3
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• pp.113-127
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• 2016

Among the techniques for recommendation, collaborative filtering (CF) is commonly recognized to be the most effective for implementing recommender systems. Until now, CF has been popularly studied and adopted in both academic and real-world applications. The basic idea of CF is to create recommendation results by finding correlations between users of a recommendation system. CF system compares users based on how similar they are, and recommend products to users by using other like-minded people's results of evaluation for each product. Thus, it is very important to compute evaluation similarities among users in CF because the recommendation quality depends on it. Typical CF uses user's explicit numeric ratings of items (i.e. quantitative information) when computing the similarities among users in CF. In other words, user's numeric ratings have been a sole source of user preference information in traditional CF. However, user ratings are unable to fully reflect user's actual preferences from time to time. According to several studies, users may more actively accommodate recommendation of reliable others when purchasing goods. Thus, trust relationship can be regarded as the informative source for identifying user's preference with accuracy. Under this background, we propose a new hybrid recommender system that fuses CF and social network analysis (SNA). The proposed system adopts the recommendation algorithm that additionally reflect the result analyzed by SNA. In detail, our proposed system is based on conventional memory-based CF, but it is designed to use both user's numeric ratings and trust relationship information between users when calculating user similarities. For this, our system creates and uses not only user-item rating matrix, but also user-to-user trust network. As the methods for calculating user similarity between users, we proposed two alternatives - one is algorithm calculating the degree of similarity between users by utilizing in-degree and out-degree centrality, which are the indices representing the central location in the social network. We named these approaches as 'Trust CF - All' and 'Trust CF - Conditional'. The other alternative is the algorithm reflecting a neighbor's score higher when a target user trusts the neighbor directly or indirectly. The direct or indirect trust relationship can be identified by searching trust network of users. In this study, we call this approach 'Trust CF - Search'. To validate the applicability of the proposed system, we used experimental data provided by LibRec that crawled from the entire FilmTrust website. It consists of ratings of movies and trust relationship network indicating who to trust between users. The experimental system was implemented using Microsoft Visual Basic for Applications (VBA) and UCINET 6. To examine the effectiveness of the proposed system, we compared the performance of our proposed method with one of conventional CF system. The performances of recommender system were evaluated by using average MAE (mean absolute error). The analysis results confirmed that in case of applying without conditions the in-degree centrality index of trusted network of users(i.e. Trust CF - All), the accuracy (MAE = 0.565134) was lower than conventional CF (MAE = 0.564966). And, in case of applying the in-degree centrality index only to the users with the out-degree centrality above a certain threshold value(i.e. Trust CF - Conditional), the proposed system improved the accuracy a little (MAE = 0.564909) compared to traditional CF. However, the algorithm searching based on the trusted network of users (i.e. Trust CF - Search) was found to show the best performance (MAE = 0.564846). And the result from paired samples t-test presented that Trust CF - Search outperformed conventional CF with 10% statistical significance level. Our study sheds a light on the application of user's trust relationship network information for facilitating electronic commerce by recommending proper items to users.

• Korean Journal of Construction Engineering and Management
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• v.21 no.2
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• pp.59-69
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• 2020

The regulation of business area was abolished to improve the competitiveness of the construction industry and the ability of general and specialty contractors to enter the mutual market. As the next step, the government is preparing for a reorganization of business type. If the impact of the abolishing of business area on the construction industry is analyzed, the result can contribute to determining the step by step application scope of the reorganization of business type. This study derived the business types having a high probability of the mutual market entry of general and specialty contractors. Then, the size of mutual market entry is analyzed. First, the connection between the general and specialty construction, and the similarities between the registration standards of general and specialty construction are analyzed. Based on the result, a general contractor can enter 15 business types of specialty construction, and the market size is about 78.8 trillion KRW. This is about 82% of the total contract cost of specialty construction during the year 2017 (about 96 trillion KRW). Next, based on the relevance of business contents, the market size when general contractors enter the specialty construction market is analyzed. As a result, the market size is about 24.7 trillion KRW, and this is about 13% of total contract cost of general construction during the year 2017 (about 190 trillion KRW). Based on the result of this study, there is a higher probability of the mutual market entry of general contractors into specialty construction than vice versa. However, the result of this study is based on the current contents of business types, registration standards, and construction data of before abolishing the regulation of business area. This is a research limitation. If the business contents and registration standards are changed in the future, the result could differ from the current result.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.3
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• pp.298-305
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• 2017

Atopic dermatitis is a chronic, relapsing inflammatory skin disease. This study aimed to investigate the therapeutic benefits of Aronia melanocarpa (AM) and Moringa oleifera seed extract (MO) on experimental atopic dermatitis. We examined the effects of AM or MO and their combination on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis in BALB/c mice as well as tumor necrosis factor $(TNF)-{\alpha}$ and interferon $(IFN)-{\gamma}-stimulated$ HaCaT keratinocytes. Mice were orally treated with extract during repeated application of DNCB to shaved dorsal skin. Our results show that treatment with AM and MO in combination reduced histological manifestations such as epidermal hyperplasia and inflammatory cell infiltration. Furthermore, it significantly decreased skin thickness and serum immunoglobulin E (IgE) level compared to the AM or MO alone treated group. Combined extract of AM and MO suppressed expression of $TNF-{\alpha}/IFN-{\gamma}-induced$ T helper 2 (Th2) chemokines such as thymus and activation-regulated chemokine and macrophage-derived chemokine. To sum up, combination of AM and MO suppressed the inflammatory response and serum IgE as an indicator of several allergic diseases in DNCB-induced experimental atopic dermatitis and Th2 chemokine expression in HaCaT cells. This result suggests that combination of AM and MO could be a valuable strategy to improve atopic dermatitis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.997-1011
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• 2017

This study aimed to evaluate the applicability of "food and nutrition standards for child care setting in the Seoul Metropolitan Government" using quantitative and qualitative surveys and lay the groundwork for future expansion. To evaluate the understanding and applicability of each item of the standards and utilize goodness of fit as an evaluation item to improve practicality of the child care center's health foodservice, we surveyed 82 child care centers, kindergartens, and community children centers in Seoul by e-mail through the Seoul Metropolitan Government in November 2015. Using focus group interviews with directors of child care centers and kindergartens as well as dieticians of child care support centers who had conducted public foodservice in Seoul, the appropriateness of each standard was finally reviewed, and amendments to extend this standard were derived. Results of the survey show an understanding of 86.9% and an applicability of 80.7%. Moreover, the applicability of the evaluation items for assessing improvement of health foodservice practices at the child care center was 82.6%. Qualitative evaluation of the applicability of standards through focus group interviews identified four factors for extended application: necessity of a guideline for separate food ingredient suppliers, conformity of the basis and purpose of the item, consideration of contextual situations, and necessity of establishing a Seoul-level foundation. Therefore, guidelines for the standards should be suggested for those providing public food services for children. Furthermore, separate guidelines categorized by items that food ingredient suppliers need to provide should be mandatory or recommended. Evaluation of the applicability of the standards suggests that revising and supplementing the guidelines in order to extend the standards can contribute to health promotion and a sustainable environment for children using public foodservice. Follow-up studies and supports are needed for sustainable food and nutrition management programs.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.170-176
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• 1998

Nitrogen and phosphorus loads from an agricultural watershed of the Yulmun-chon tributary in the Buk-Han River Basin were quantified based on total amounts of water stream flow. The water quality and soil loss were estimated. Levels of the stream were recorded automatically using the water level meter. The flow velocities, along with the cross-sectional areas of the riverbed, were measured to estimate total amounts of water flow at three monitoring sites in this tributary. Water samples were collected at nine sites with two weeks interval from May to August and analyzed for the water quality parameters. Amounts of soil loss were estimated by the USLE. The size of the Yulmunchon watershed was 3,210 ha, of which paddy and upland soil areas were composed about 41%. The total amounts of soil loss from the watershed areas were estimated to be $13,273Mg\;year^{-1}$, showing 53%, 46% and 0.7% of the soil loss ratio from upland, forest, and paddy areas, respectively. Electrical conductivities and Nitrogen concentrations of the stream water were higher in the lower watershed area than in the upper area. Increments of N were higher for $NO_3-N$ than $NH_4-N$. Nitrate nitrogen was the major N form to pollute the water due to the agricultural activity. Total runoff was about 72% of the total precipitation in the watershed. The maximum loads of T-N and T-P due to the runoff were estimated to be 1,500 and $5kg\;day^{-1}$, respectively. Concentrations of $NO_3-N$ and $NH_4-N$ in the runoff were 13.5 and 1.8 times higher than those in precipitation. The N loads were mainly from soil loss, application of fertilizer, and livestock wastes, which were 52% of total N load. Results demonstrated that reduction of fertilizer use and the soil loss would be essential for water quality protection of the agricultural watershed.

• Journal of Korean Home Economics Education Association
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• v.28 no.3
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• pp.1-16
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• 2016

The purpose of this study was to develop and evaluate the teaching-learning process plan of senior cohousing to improve understanding of active and independent living in later life through Home Economics subject. The plan consisting of 5 lessons has been developed and implemented according to the ADDIE model. Various activity materials (28 individual activity sheets, 2 working sheets, and 26 teacher's reading texts) and visual materials (4 sets of pictures & photos and 10 moving pictures) as well as questionnaire were developed for the 5-session lessons. The plans were implemented to 6 classes 150 freshmen of P high school in Jeju-do during August 17th to 3rd of September, 2015. Students were highly satisfied regardless of gender with the whole 5-lessons in the aspects such as the level of participation in the lesson, understanding of the contents, adequacy of materials and activities, and usage in their future life. Students also reported that they highly accomplished the goal of each lesson to reinforce the understanding on necessity of preparing later life, senior cohousing, and senior friendly business. It can be concluded that the teaching learning process plan for senior cohousing would improve understanding and practical competency of active and independent living in later life with senior neighbors through the home economics subject.

• Journal of Bio-Environment Control
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• v.27 no.2
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• pp.140-146
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• 2018

This research was conducted to determine the influence of incorporation levels of sulfur into a coir dust+pine bark medium (1:1, v/v) on the changes in the bicarbonate ($HCO_3{^-}$) concentrations and pH of soil solution, crop growth, and nutrient uptake of 'Ssanta' strawberry. In the preparing of the mixed medium, sulfur powder was added with the rate of 0 (control), 0.23, 0.45, 0.90, and $1.80g{\cdot}L^{-1}$ and Hoagland nutrient solution containing $240mg{\cdot}L^{-1}$ $HCO_3{^-}$ was supplied during the crop cultivation. The growth measurements and tissue analysis for the determination of nutrient contents were carried out 140 days after solution application and the soil solution analysis was performed every two weeks. As the level of sulfur was elevated, the overall growth of mother plants became better showing that the growth indexes except chlorophyll contents were the lowest in control treatment but the statistical differences were not found among the three treatments of $0.45g{\cdot}L^{-1}$ or higher sulfur. The higher the levels of sulfur incorporation, the higher the occurrence of runners and the growth of daughter plants. The length of the runners and the number of daughter plants occurred per mother plants were higher in the treatments of 0.90 and $1.80g{\cdot}L^{-1}$ than the three treatments of 0, 0.23, and $0.45g{\cdot}L^{-1}$, but the statistical differences were not observed between the 0.90 and $1.80g{\cdot}L^{-1}$ treatments. The rose of pH and $HCO_3{^-}$ concentrations in soil solution of root media continued all the cropping period, but those decreased slightly in the treatments of $0.90g{\cdot}L^{-1}$ or higher. The soil solution concentrations of $K^+$ and $PO_4{^3-}$ in the treatments of 0.90 and $1.80g{\cdot}L^{-1}$ was lower than those in other treatments and the statistical differences in the $Ca^{2+}$ and $Mg^{2+}$ concentrations were not observed among all treatments. The nutrient contents in tissue analyzed in this experiment were the lowest in the control treatments and those increased as incorporation rates of sulfur were elevated. Above results indicated that when 'Ssanta' strawberry is grown hydroponically and the root medium is coir dust and the pine bark (5:5, v/v) mix, the sulfur incorporation rate as pre-planting fertilizer has to be higher than $0.9g{\cdot}L^{-1}$ root medium to reduce the $HCO_3{^-}$ injury.

• Journal of Korean Society of Transportation
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• v.18 no.1
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• pp.75-85
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• 2000

In existing models in optimization, the crisp data improve has been used in the objective or constraints to derive the optimal solution, Besides, the subjective environments are eliminated because the complex and uncertain circumstances were regarded as Probable ambiguity, In other words those optimal solutions in the existing models could be the complete satisfactory solutions to the objective functions in the Process of application for industrial engineering methods to minimize risks of decision-making. As a result of those, decision-makers in location Problems couldn't face appropriately with the variation of demand as well as other variables and couldn't Provide the chance of wide selection because of the insufficient information. So under the circumstance. it has been to develop the model for the location and size decision problems of logistics facility in the use of the fuzzy theory in the intention of making the most reasonable decision in the Point of subjective view under ambiguous circumstances, in the foundation of the existing decision-making problems which must satisfy the constraints to optimize the objective function in strictly given conditions in this study. Introducing the Process used in this study after the establishment of a general mixed integer Programming(MIP) model based upon the result of existing studies to decide the location and size simultaneously, a fuzzy mixed integer Programming(FMIP) model has been developed in the use of fuzzy theory. And the general linear Programming software, LINDO 6.01 has been used to simulate, to evaluate the developed model with the examples and to judge of the appropriateness and adaptability of the model(FMIP) in the real world.