• The KSFM Journal of Fluid Machinery
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• v.16 no.1
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• pp.11-16
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• 2013

A numerical study was conducted to improve the performance of an impeller of centrifugal compressor. Nine design variables were chosen with constraints. Only meridional contours and blade profile were adjusted. ANN (Artificial Neural Net) was adopted as a main optimization algorithm with PSO (Particle Swarm Optimization) in order to reduce the optimization time. At first, ANN was learned and trained with the design variable sets which were obtained using DOE (Design of Experiment). This ANN was continuously improved its accuracy for each generation of which population was one hundred. New design variable set in each generation was selected using a non-gradient based method of PSO in order to obtain the global optimized result. After $7^{th}$ generation, the prediction difference of efficiency and pressure ratio between ANN and CFD was less than 0.6%. From more than 1,200 design variable sets, a pareto of efficiency versus pressure ratio was obtained and an optimized result was selected based on the multi-objective function. On this optimized impeller, the efficiency and pressure ratio were improved by 1% and 9.3%, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.2
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• pp.333-345
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• 1997

The purposes of this study were 1) to identify the differences between the sexes in the perception of sexuality in jeans fashion advertising, 2) to find out the differences between the high and low sexy advertisements and the differences between the groups which had different orientation of the characteristics of new young generation in preferences of advertisements and intentions to purchase product in sexy fashion advertising. The data were collected using questionnairs which contained nine advertisements of Guess Jeans, from 441 college students (female= 225, male= 216) living in Seoul, Korea participated in the study and the data were and analyzed by paired 1·test and t-test. The results of this study were as follows: First, there were significant differences between male and female in the perceptions of sexuality in jeans advertisements. Second, by paired t-test, male preferred highly sexy advertisement to low sexy advertisement, and female's intention to purchase product was higher in the advertisement of high sex appeal than that of low sex appeal. Third, there were partially significant diferences between two groups which had different orientation of the characteristics of new young generation in preferences of sexy advitisements. The differences of intentions to purchase product between two groups were significant in highly sexual advertising. But in low sexual advertising, the significant differences between two groups were not found in advertisement preferences and intentions to purchase products.

• Journal of the Korean Home Economics Association
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• v.35 no.3
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• pp.63-75
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• 1997

The purposes of this study was to identify the differences between fashion opinion leaders and followers in the characteristics oriented New Young Generation and the types of fashion advertising involvement. The data were collected via a questionnaire from 431 college students(female=218 male=213) living in Seoul, Korea and analyzed by factor analysis and t-test. The results of this study were as follows: First, eight factors of the characteristics oriented New Young Generation were identified: Fashion, individuality, preference of caffe with affective mood, expression of emotion, indivisualism, preference of tastes oriented Western Europe, activity of pan club and chatting by personal computer. The significant differences between fashion opinion leaders and followers in fashion, individuality, preferences of the caffe with affetive mood, and expression of emotion were found in the data collected from female. There were significant differences between fashion opinion leaders and followers in fashion, individuality in the data collected from male. Second, three factors of fashion involvement advertising were identified: The hedonic involvement, social involvement, utilitarian involvement. The significant differences between fashion opinion leaders and followers in the hedonic involvement, social involvement, utilitarian involvement and the levels of involvement were found in the case of female's data. There were significant differences between fashion opinion leaders and followers in the hedonic involvement, social involvement and levels of involvement except for utilitarian involvement in the case of male's data.

• The KSFM Journal of Fluid Machinery
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• v.11 no.3
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• pp.22-29
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• 2008

Clean and renewable energy technologies using ocean energy give us non-polluting alternatives to fossil and nuclear-fueled power plants to meet establishment of countermeasures against the global warming and growing demand for electrical energy. Among the ocean energy resources, wave power takes a growing interest because of its enormous amount of potential energy in the world. Therefore, various types of wave power conversion system to capture the energy of ocean waves have been developed. However, suitable turbine type is not normalized yet because of relatively low efficiency of the turbine systems. The purpose of this study is to investigate the internal flow and performance characteristics of a cross-flow type hydro turbine, which will be built in a caisson for wave power generation. Numerical simulation using a commercial CFD code is conducted to clarify the effects of the turbine rotation speed and flow rate variation on the turbine characteristics. The results show that the output power of the cross-flow type hydro turbine with symmetric nozzle shape is obtained mainly from Stage 2. Turbine inlet configuration should be designed to obtain large amount of flow rate because the static pressure and absolute tangential velocity are influenced considerably by inlet flow rate.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.1
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• pp.15-22
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• 2019

This study analyzed the correlation between generation of municipal solid waste (MSW), number of tourists, and area of accommodation facilities of small island such as Shin, Si, Mo and Jangbong island in Ongjin county, Incheon for use as basic data for estimation of MSW generation. An analysis of statistics data from september in 2012 to august in 2018 showed MSW generation was steadily increasing, and MSW generation in 2018 was increased by about 3.98 times compared to 2012. In summer, which is the tourist season, MSW generation was 2.43~9.39 times higher than in winter. MSW generation was influenced by the number of tourists. As of August 2018, generation rate of per capita of MSW was $0.839kg/cap{\cdot}day$, which was about 3.71 times higher than August 2013. Area of accommodation increased continuously from 2008 to 2017, increasing by about 8.32 times. The coefficient of determination between the area of accommodation and the number of tourists was 0.8418. Also coefficient of determination between area of accommodation and MSW generation were 0.9370 and 0.6025 before and after August in 2015, respectively. Accommodation was lacked due to increase of tourists. Although accommodation was scarce because of increase in the number of tourists since 2015, the coefficient of determination decreased due to the increase in waste generation.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.3
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• pp.11-17
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• 2011

In this paper, we propose method of the social scenario generation that maximize public`s participation taking advantage of a Social Network Service technology to overcome limit of scenario generation formed in existent analog space. The method is novel because digital technology was used only in storytelling, and never used in improving the quality of information introducing in scenario generation. Existent scenario generation was apt to lean in subjective thinking of individual and when handle story of professional field, there was difficulty because it was writer individual`s generation. Entrance on the stage of digital scenario generation programs was standardized form of scenario, but This limitation did not still solve. Therefore, whatever make scenario in digital space, scenario generation is still depending on only writer individual`s ideas. By method that overcome this limit, we propose social scenario generation that use SNS that writer can accommodate opinions of many people and relevant informations up to date.

• Fashion & Textile Research Journal
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• v.24 no.1
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• pp.81-94
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• 2022

The purpose of this study is to analyze the trends of MZ generation's lifestyle-related research from 2010 to 2020. As a result of searching keywords such as MZ generation's and lifestyle using academic database search sites, a total of 218 cases were used as analysis data to conduct frequency and content analysis. First, research type was 74 dissertations(34.6%), 144 journals(65.4%). The study of MZ generation was relatively active in journals. Second, the current status of academic field was 85(39.7%) in the social field, followed by 66(30.8%) in the arts/physical education, 21(9.8%) in the complex studies, 16(7.5%) in education, 15(7.0%) in nature, 6(2.8%) in engineering, 4(1.9%) in humanities, 1(0.5%) in agriculture/marine. Third, the current status of MZ generation research topics is 54 social participations(25.3%), 35 fashion/beauty(16.3%), 31 social/organizational adaptations(14.5%), 25 cultural/leisure activities(11.7%), 24 design/development projects(11.2%), 21 economic/employment/job projects(9.8%), 11 educational/career/experiences(5.1%), 9 self-concepts(4.2%), 4 welfare services(1.9%). Fourth, the current status of MZ generation research methods was quantitative research(survey/experiment) 125(58.4%), qualitative research(depth interview/participant observation) 42(19.6%), theory/literature research 35(16.4%) and mixed research 12(5.6%). Fifth, the study on the lifestyle of the MZ generation was conducted in four cases, one in 2016, one in 2019, two in 2020. This study is meaningful in that it grasped the overall flow of data of information exchange that can share the research trends of the MZ generation and suggested the basic data on the direction of future research, the individual tendency, behavior, and lifestyle characteristics of the MZ generation.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.386-396
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• 2018

The purpose of this study is to examine young Koreans' welfare attitudes towards youth policy and to analyze the determinants on such attitudes. The main results are as follows. Many young people(72.1%) understand that government should be responsible for youth support and spending on youth support policy(49.5%) and job support policy(59.7%) should be expanded than current level. But only 24.1% approved the provision of youth allowance. There was a significant in-group heterogeneity among the young generation in terms of support for expanding fiscal spending for youth policy and youth allowance provision. Results from the regression analysis indicated sex, age, education level, employment status, type of housing affect attitudes towards youth policy and statistical significance of them was different according to each analytic model. Korean young adult generally perceived that our society was unequal and the higher the perception of inequality, the higher support for youth policy. These results implicates that in-group heterogeneity among youth generation in terms of socio-economic needs and subjective perception should be regarded as important factor in the youth policy making process.

• Journal of Digital Convergence
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• v.10 no.5
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• pp.167-175
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• 2012

The purpose of this paper is a study of the next generation innovation to deal with changing business environment in which the competition is getting fierce. The ultimate goal of a company is to sustain and grow by creating value or profit continuously. As the social or business environment changes, the way of creating profits also changes. Therefore, business management or innovation should be evolved in accordance with the value change, and this gives basis to the question "What would the next generation innovation be like?". This paper is not to give the definite answer to the next generation innovation, but to get discussion started. We hope that many ideas, critiques and opinions to this paper will make the next generation innovation clear.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.95_96
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• 2009

In this paper, a new algorithm of Integrated Volt/Var Control (IVVC) is proposed using Volt/Var control for the Distribution Automation System (DAS) based on the modeling of the distributed load and the distributed current. In the proposed, the load flow based on the modeling of the distributed load with Distributed Generation and the distributed current are estimated from constants of four terminals using the measurement of the current and power factor from a Feeder Remote Terminal Unit (FRTU). For Integrated Volt/Var Control (IVVC), the gradient method is applied to find optimal solution for tap and capacity control of OLTC (On-Load Tap Changers), SVR (Step Voltage Regulator), and SC (Shunt Condenser). What is more Volt/Var control method is proposed using moving the tie switch as well as IVVC algorithm using power utility control. In the case studies, the estimation and simulation network have been testified in Matlab Simulink.