• 한국기계가공학회지
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• 제12권3호
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• pp.69-75
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• 2013

During the magnetic abrasive polishing of a curved surface, the improvement in surface roughness varies with the maximum value and distribution of magnetic flux density. Thus, in this study, the magnetic flux density on the curved surface was simulated according to curvature radii of magnetic tool. As a result of the simulation, the 14.5mm of the magnetic tool had a higher maximum magnetic flux density and it showed a large weighted magnetic flux density. The weighted magnetic flux density means the highest value for the magnetic flux density in the curvature of the magnetic tool. From the experimental verification, the better improvement in surface roughness was observed on wider area at the 14.5mm radius of the magnetic tool than other radii.

• 전력전자학회논문지
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• 제17권3호
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• pp.205-212
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• 2012

This paper proposes the fuzzy logic based variable step-size MPPT (Maximum Power Point Tracking) method for the stability at the steady state and the improvement of the transient response in the wind power system. If the change value of duty ratio is set on stability of the steady state, MPPT control traces to maximum power point slowly. And if the change value is set on improvement of the transient response, the system output oscillates at the maximum power point. By adjusting the step size with fuzzy logic, it can be improved the MPPT response speed and stability at steady state when MPPT control is performed to track the maximum power point. The effectiveness of the proposed method has been verified by simulations and experimental results.

• Nuclear Engineering and Technology
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• 제44권7호
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• pp.799-806
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• 2012

In recent years, a new algorithm has been introduced to perform the regional overpower protection (ROP) detector layout optimization for $CANDU^{(R)}$ reactors. This algorithm is called DETPLASA. This algorithm has been shown to successfully come up with a detector layout which meets the target trip set point (TSP) value. Knowing that these ROP detectors are placed in a number of safety channels, one expects that there is an optimal placement of the candidate detectors into these channels. The objective of the present paper is to show that a slight improvement to the TSP value can be realized by optimizing the channelization of these ROP detectors. Depending on the size of the ROP system, based on numerical experiments performed in this study, the range of additional TSP improvement is from 0.16%FP (full power) to 0.56%FP.

• 한국의류학회지
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• 제9권2호
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• pp.27-34
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• 1985

Cotton, P/C and polyester fabrics were laundered and treated with 4 kinds of aftertreating agent(antistatic and softening agents) on marketing. Some treating condition:. which include agent concenteration, treating time and rinsing extent after laundering, were varied. And then the effects of agents with each treating condition-handle value, charged voltage and half-life, and crease recovery etc.-were determined and discussed about their change. The improvement of handle and antistatic properties by treatment were indicated remarkably for cotton fabric and P/C and polyester fabrics respectively. Generally, the handle value of cotton was decreased and then increased again, and the charged voltage and half-life of P/C and polyester fabrics were decreased with increase of concenteration of agents. The effect of antistatic improvement for P/C fabric was larger than polyester fabric at even lower concenteration of agents. The effects were increased with treating time and rinsing extent. In particular, those of short time(1 minute) treatment were very small.

• International Journal of Aeronautical and Space Sciences
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• 제7권1호
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• pp.1-12
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• 2006

In this study, a surrogate model is applied to multi-objective aerodynamic optimization design. For the balanced exploration and exploitation, each objective function is converted into the Expected Improvement (EI) and this value is used as fitness value in the multi-objective optimization instead of the objective function itself. Among the non-dominated solutions about EIs, additional sample points for the update of the Kriging model are selected. The present method was applied to a transonic airfoil design. Design results showed the validity of the present method. In order to obtain the information about design space, two data mining techniques are applied to design results: Analysis of Variance (ANOVA) and the Self-Organizing Map (SOM).

• Design & Manufacturing
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• 제12권3호
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• pp.55-59
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• 2018

In a multi-cavity mold having a runner layout of a fish bone structure, problems of unbalanced filling between cavities occur constantly. Unbalanced charging lowers the dimensional accuracy of a molded article and causes deformation after molding. To solve this problem, the gate size connected to each cavity is adjusted using the BGV (Balanced Gate Value) equation. In this paper, in order to solve the filling imbalance problem of the runner layout mold of fish bone structure through injection molding analysis study, we compared the charging imbalance phenomenon before and after improvement after adjusting the gate size by applying BGV equation. From the results of the molding analysis, the shrinkage ratio before and after the improvement of the molded article was improved by only about 0.08%. Based on these results, it was confirmed that the charging imbalance problem was not significantly improved even when the BGV equation was applied.

• KDI Journal of Economic Policy
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• 제40권4호
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• pp.47-63
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• 2018

Government R&D grants for SMEs have risen to three trillion Korean won a year, placing Korea second among OECD nations. Indeed, analysis results have revealed that government support has not only expanded corporate R&D investment and the registration of intellectual property rights but has also increased investment in tangible and human assets and marketing. However, value added, sales and operating profit have lacked improvement owing to an ineffective recipient selection system that relies solely on qualitative assessments by technology experts. Nevertheless, if a predictive model is properly applied to the system, the causal effect on value added could increase by more than two fold. Accordingly, it is important to focus on economic performance rather than technical achievements to develop such a model.

• 농촌지도와개발
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• 제11권1호
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• pp.37-52
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• 2004

The rural living improvement in Japan operates in considerations of socio-eoonomic circumstances of rural community as in Korea. After 1945 the program emphasized the improvement of living conditions such as poverty alienation improvement of house and toilet nutrition after war, From 1955, health programs including better cooking and nutrition, house modification and improved living conditions corresponding to the goal of the developed country were carried out. In 1965. the goal of the rural home economics was focused on the harmonized production and living, improvement of the levels of rural living, health and building rural community. From 1975, the goals of the program were to organize the farming in the better ways and improvement of rural women's role. In 1985, making agreeable living conditions was emphasized under the goal of vital rural society. From the period of Heysey(1989${\sim}$), for better living of rural people the government is emphasizing the programs including farm labor management, utilization of farm products, farm management and rural environments. Recognizing the important influencing resources of agents in extension services, on the job and education was implemented step by step from basic to planning to upgrade competencies. The government is trying to construct better with infrastructures, encouraging direct selling the value-added processed food from local farm products with rural people's real name and other countryside resources. Major programs in the 21st centuries are building better rural society with men and women together and considering elders as well as new farmers.

• 유통과학연구
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• 제19권10호
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• pp.5-15
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• 2021

Purpose: This study aims to present individual motivation and channel characteristics affecting omnichannel service use, as well as the effect relationship of the brand factor on consumption value, service satisfaction, and continuous usability based on convenience store pickup service, one of online shopping customers' omnichannel use services. Primarily, this study divided consumption value into emotional value and functional value and examined the consumption value characteristics of omnichannel-based pickup service customers. Research design, data and methodology: A questionnaire survey was carried out targeting 324 consumers having the omnichannel-based pickup service user experience in online shopping in Korea. A confirmatory factor analysis and path analysis were carried out based on the structural equation to verify hypotheses. Results: According to the analysis result, individual motivation affected the emotional value, and the omnichannel characteristics affected functional value. The brand effect influenced both emotional and functional values. The emotional value affected continuous use intention, and the functional value affected service satisfaction. Conclusions: Therefore, consumers' emotional and functional values showed differences in consumption behavior. In online shopping companies' marketing strategy construction for omnichannel, it was confirmed that a differentiated approach is needed depending on the strategic goal of satisfaction improvement and continuous use intention consolidation.

• 한국물환경학회지
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• 제35권6호
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• pp.539-549
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• 2019

In 2016, Benthic Macroinvertebrates Streambed Index (BMSI) was proposed as an index to evaluate streams as benthic macroinvertebrate depending on the substrate type of streambed. However, orignal BMSI were selected without consideration of water quality. Analyzes without water quality do not constitute biological indices based solely on the substrate type of streambed. Therefore, in this study, the indicator value was improvement in consideration of water quality, and the distribution characteristics of benthic macroinvertebrates according to the substrate type of streambed were analyzed under relatively equal water quality conditions. We surveyed 20,155 sampling units in Korea from 2008 to 2018, and we re-estimated each lithophility of 191 taxa. As a result of estimating the streambed of each newly lithophilic value classification group considering the water quality, it was different from the original lithophilic value. Representative integer lithophilic values were newly calculated from 126 taxa among the 191 index taxa used in the analysis. The correlation between new constructed BMSI and community structure was compared and analyzed. It showed extreamely significance (p<0.001) in the dominance index, diversity index, abundance index, and evenness index of the community structure. Diversity index, abundance index, and evenness index showed positive correlation, and dominance index showed negative correlation. The correlation coefficient (r) was the highest in the richness index of about 0.664.