• Korean Chemical Engineering Research
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• 제44권5호
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• pp.489-497
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• 2006

The economical efficiency of conversion of the PC (pulverized coal) firing boiler to the CFB (circulating fluidized bed) boiler which used Koran anthracite as fuel was evaluated. The economic feasibility study was also carried out with regard to maintenance of the existing PC boiler. The sensitivity of economical efficiency with variation of the electric power and coal industry and the policy of government was analyzed and compared. As a results of the evaluation, the economical efficiency of maintenance of the existing PC boiler was higher than that of conversion to the CFB boiler because of the special policy of the government for Korean anthracite. However, the conversion to the CFB boiler was more economically attractive from a point of view of effective use of energy resources and future electric power industry. Additionally, the fund support for electric power industry using Korean anthracite would be effective as changing the policy of the government.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제34권9호
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• pp.1331-1338
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• 2010

Recently, the need for improving the economical efficiency of pumped-storage power plants has increased because of the decrease in the availability of electricity caused by an increase in the consumption of electricity at night. Therefore, a preventative maintenance cycle, especially an overhaul cycle, is required. Unconditional extension cannot be implemented because it may cause unanticipated failures due to insufficient maintenance. Therefore, in this study, a methodology for optimizing the preventative maintenance cycle by taking into account both reliability and economical efficiency is presented; this methodology has been developed by reviewing previous studies on reliability and considering the characteristics of pumped-storage power plants. Finally, an extended overhaul cycle is derived by applying this methodology to a domestic pumped-storage power plant.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제17권2호
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• pp.45-57
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• 2016

This study examined the effect factors for the preparations for the old age on the current satisfaction of life of the middle-aged. A survey of middle aged people living in Seoul and metropolitan areas was conducted. The data from 442 subjects were collected from 450 questionnaires excluding 8 incomplete datasets and analyzed. The results were as follows. First, the emotional and economical preparations for the old age had influences on the emotional satisfaction positively. Second, the educational background, jobs for technician/working, emotional and physical preparations for old age had a positive effect on the physical satisfaction. Third, the household income, emotional and economical preparation for the old age had a positive influence on the economical satisfaction. Fourth, sex, emotional preparations for old age had a positive effect on the social relation satisfaction. The research results suggested that the preparations for the old age should be arranged from the middle-aged years because it is difficult to improve the satisfaction of life for old age in the elderly.

• Korean Management Science Review
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• 제26권3호
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• pp.185-204
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• 2009

Power bloggers have become one of the most important resources of blog service companies, and only those who attract and secure power bloggers will be able to have competitive edge and profitability in blog related businesses. This study examines the effects of technology acceptance factors and economical factors on the loyalty of power bloggers. The analysis results show that the usefulness, power of social influence and enjoyment positively affect the attitude and intention to continuous use. The relationship between the attitude and intention to continuous use is demonstrated as significant. The economical benefit exhibits weakly positive influence on the attitude to blogging, but not on the intention. This indicates that although many power bloggers receive economic benefits through their blogging activities, such economical benefits do not have big impact on their activities and the intention to use. The blog service providers may use the analysis results when developing new blog services. In particular, the usefulness, which is often considered as one of the most important factors in the success of the blogosphere, is found to have less impact than the enjoyment among power bioggers. This is because blog users, especially power bloggers, use the blog not for a specific purpose or for generating a special product; most of them use the blog to satisfy their own personal desires. When developing blog services, therefore, it is important to cater to the users' enjoyment and their psychological compensation. What is surprising is that the effect of the economical factor is not ad significant as one might have expected. This implies that the new blog services that provide profit sharing or advertising revenue sharing may not be as successful as one would have hoped for in maintaining the loyalty of power bloggers.

• Journal of the Korea Fashion and Costume Design Association
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• 제12권4호
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• pp.1-13
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• 2010

The purpose of this study is to examine the different preference as well as the factor for this preference between general internet shopping mall and feminine internet fashion shopping mall only which are subjected with women and know the satisfaction which follows hereupon. This research will help to establish the strategy to marketers who manage feminine internet fashion shopping mall. The results of this study as follows; 1. As the result of the analysis of preference factors for general internet shopping mall, it was classified with, convenient characteristic, economical efficiency, product and information characteristic, sales promotion, and customer service. Also differences among preference factors appear with following orders, economical efficiency, convenient characteristic, product and information characteristic, sales promotion, and customer service. 2. As the result of the analysis of preference factor for feminine internet fashion shopping mall, it was classified with, fashion information and style, purchase product, economical efficiency, product assortment, and customer service. Also differences among preference factors appear with following orders, fashion information style, product assortment, purchase product, economical efficiency, and customer service. 3. As the result of the analysis of preference factors, convenient characteristic and product information mostly effects to satisfy the customers who use general internet shopping mall. Also purchase product, product assortment, fashion information and style mostly effects to satisfy the customers who use feminine internet fashion shopping mall.

• Explosives and Blasting
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• 제27권1호
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• pp.47-52
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• 2009

Blasting is necessary for excavation processes since more than 70% of korean land is consist of mountains. The vibration and noise accompanied by blasting processes usually bring about public complaints. Blasting patterns are chosen by economical efficiency, stability and construction conveniency. However, there are many alternatives without control to settle the popular complaint. To prevent those alternatives, standard blasting method for design and construction were suggested by MLTM (Ministry of Land, Transport and Maritime Affairs) in 2006. However, standard blasting pattern of MLTM was designed in a lump irrespective of types of rocks. Economical loss may occur by ignoring the characteristics of rocks for the applications to the rocks with low intensity, such as shale, or containing many joint. We deduced some economical progresses by performing test blasting with adjusted drilling spacing and length of burden considering the characteristics of local rock. This paper suggests the start of case studies for different applications. Economic improvement can be expected by applying those results deduced from case studies to design and construction.

• Journal of Environmental Science International
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• 제22권7호
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• pp.905-913
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• 2013

We compared the applicability and economical efficiency of peroxone process with those of ozone process in the existing water treatment plant on downstream of Nakdong River. After comparing the peroxone process for removing geosmin with the ozone process in lab scale test, peroxone process showed much higher removal efficiency than the ozone process at the same ozone dosage. Proper range of $H_2O_2/O_3$ ratio were 0.5~1.0 and the half-life of geosmin was about 5.5~6.8 min when the $H_2O_2/O_3$ ratio was set to 0.5 during 1~2 mg/L of ozone dosage. Peroxone process could reduce the ozone dosage about 50 to maximum 30% for the same geosmin removal efficiency compared to the ozone process in the pilot scale test. In case of 1,4-dioxane treatment, peroxone process could have 3~4 times higher efficiency than ozone process at the same ozone dosage. The results of estimating the economical efficiency of ozone and peroxone process for treating geosmin and 1,4-dioxane by using pilot scale test, in case of the removal target was set to 85% for these two materials, the cost of peroxane process could be reduced about 1.5 times compared to ozone process, and in the same production cost peroxone process could have 2~3 times higher removal efficiency than ozone process. The removal efficiency by peroxone process showed a large difference depending on the physicochemical characteristics of target materials and raw water, therefore detailed examination should be carried out before appling peroxone process.

• Human Ecology Research
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• 제53권3호
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• pp.253-263
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• 2015

This study investigates the effect of consumer culture and awareness of wedding ceremonies between parents and children as well as preference for a simple wedding in order to develop a simple wedding concept. The data for statistical analysis came from 375 of children 216 and parents 159. Data was analyzed with t -test, analysis of variance, exploratory factor analysis, Cronbach's $\alpha$ and regression analysis by SPSS ver. 18.0. The results were summarized as follows. First, children had a higher symbolic consumption than parents and parents had a higher functional consumption than children. Second, children prefer a discriminate and characteristic small wedding, while parents prefer an economical, meaningful and nonconforming simple wedding. The variables that effect parents simple wedding preferences were consumer culture, awareness of wedding ceremony, gender, and education; those of children were, consumer culture, awareness on wedding ceremony, gender, and age. Children had a functional and economical consumption focused on meaningfulness and rationale of the wedding, they prefer an economical meaningful small wedding. Children had functional consumption that prefers a discriminate characteristic small wedding and a nonconforming small wedding compared to men. Parents did not have symbolic consumption and focused on the meaningfulness and rationale of the wedding, they prefer an economical meaningful small wedding. Parents focused on the meaningfulness and rationale of the wedding; in addition women prefer a discriminate characteristic small wedding compared to men. Parents had functional consumption and focused on the meaningfulness and rationale of the wedding with a preference for a nonconforming small wedding.

• Journal of the Korea institute for structural maintenance and inspection
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• 제13권6호통권58호
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• pp.97-105
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• 2009

This study was conducted for the purpose of examinating the safety and economical efficiency of large high tension bolted joints. The specimen using F10T-M30 large high strength bolts has been selected and static tensile test has been conducted to evaluate the slip characteristics. In addition, finite element analysis has been carried out to estimate the number of required bolts. As a result, the average slip coefficient of M30 high strength bolts exceeded 0.4 - the standard in highway bridge design specification - and has satisfied the slip strength, which is the same as that of M22 high strength bolts. In addition, if F13T-M22 high strength bolts were applied, the number of required bolts decreased by 21%, and if F10T-M30 high strength bolts were applied, the number of required bolts decreased by 46%, that leads to the conclusion that the economical efficiency in accordance with diametering of high strength bolts was now verified.

• Journal of the Architectural Institute of Korea Planning & Design
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• 제34권2호
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• pp.41-48
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• 2018

This study is expected to provide some basic data on how to apply more economical and efficient eco-friendly factors to reduce the carbon emissions. It has been scrutinized and analyzed the environmental factors of passive eco-friendly elements along with active eco-friendly elements as more efficient factors for energy conservation based on the case of a newly constructed broadcasting building with the green building certification in Sangam-dong DMC area. The first analysis was the energy consumption trends in Korea and the necessity of energy saving. Secondly, it was examined the energy consumption in the current status of the broadcasting building. Thirdly, it was looked into the correlation between the eco-friendly design application factors applied to the broadcasting building and the energy consumption types. As a result of the analysis, the application of fan and feed pump inverter along with ventilation system of waste heat recovery ventilation system were more meaningful in accordance with the economic feasibility of broadcasting buildings rather than economical effect of passive elements such as rooftop garden, reinforcement of building insulation. Also, the application of lighting control had the economical feasibility. Therefore, when it is intended to change the green building certification energy related evaluation items of the similar broadcasting building types, it is necessary to change the direction of adding weight to the more economical active element items in the future.