• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.10
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• pp.4724-4747
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• 2016

To efficiently reduce on-grid energy consumption, the admission control algorithm in the hybrid energy powered cellular network (HybE-Net) with base stations (BSs) powered by on-grid energy and solar energy is studied. In HybE-Net, the fluctuation of solar energy harvesting and energy consumption may result in the imbalance of solar energy utilization among BSs, i.e., some BSs may be surplus in solar energy, while others may maintain operation with on-grid energy supply. Obviously, it makes solar energy not completely useable, and on-grid energy cannot be reduced at capacity. Thus, how to control user admission to improve solar energy utilization and to reduce on-grid energy consumption is a great challenge. Motivated by this, we first model the energy flow behavior by using stochastic queue model, and dynamic energy characteristics are analyzed mathematically. Then, fuzzy logic based admission control algorithm is proposed, which comprehensively considers admission judgment parameters, e.g., transmission rate, bandwidth, energy state of BSs. Moreover, the index of solar energy utilization balancing is proposed to improve the balance of energy utilization among different BSs in the proposed algorithm. Finally, simulation results demonstrate that the proposed algorithm performs excellently in improving solar energy utilization and reducing on-grid energy consumption of the HybE-Net.

• Journal of the Korean Solar Energy Society
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• v.21 no.3
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• pp.51-60
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• 2001

A greenhouse equipped with latent heat storage system was built to obtain various thermal properties, such as greenhouse air temperature, soil surface temperature, energy flow in latent heat storage, etc., which could be used in validation of greenhouse numerical model to be developed in this study. This numerical model expressed with Newton-Raphson method was programed by C-language and utilized to simulate greenhouse thermal behavior. Greenhouse air temperature and soil surface temperature predicted by the greenhouse model developed in this study were very close to the measured data obtained through almost 3 years of experiment. Therefore, it is concluded that the greenhouse model developed and verified by measured data could be utilized for simulating various thermal behaviors of greenhouses equipped with latent heat storage system to be used for energy saving purposes.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1175-1183
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• 2001

Recently, a great attention has been paid to the ice thermal storage system for the purpose of energy saving and reduction in peak electrical demand. In the present study, it has been investigated the freezing behavior of several kinds of water solutions with nonionic surfactant. In order to prevent ice blockage in a cooled pipe, the amount and wall adhesion behavior of ice of the test fluids were observed experimentally under different concentration of water solution with surfactant, temperature of cooled wall, and the shear velocity of test fluids. The results showed that the size of ice crystal became smaller at higher shear velocity at wall. And the lowest limit of wall adhesion of ice in water solution with surfactant was found at 230 W/$m^2$ of heat flux.

• Journal of Family Resource Management and Policy Review
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• v.13 no.4
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• pp.115-139
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• 2009

This study focused on the development of a scale measuring the effect of consumer education. The purposes of this study were to develop a tool which could measure consumer knowledge, consumer attitudes and consumer behavior. Data were collected from 266 college students. Analysis was done using frequency, cross tabulation analysis, reliability test, principle components factor analysis, confirmatory factor analysis (Amos 5.0), and multiple regression analysis. The results from this study were as follows: 1) Nine consumer knowledge factors (23-items) were identified: consciousness of consumer education and evaluation, consumer rights and allowance management, methods of consumer education and consumer institutions, green energy and environmental consumption, essence and content of consumer education, consumer rights and consumer duty, critical consideration and consumer's damage salvation, buying minds and decision-making, independent consumers. Total variance was 58.4%. Cronbach's alpha for the nine factors ranged from .68-.79. 2) Five consumer attitude factors (26-items) were identified: green environmental consumption, consumer's role and rights, resources saving and consumer's damage salvation, consciousness of consumers, and right consumption. Total variance was 59.2%. Cronbach's alpha for the five factors ranged from .89-.94. 3) Seven consumer behavior factors (27-items) were identified: social role and rights of consumer and consumer movement, right buying and segregated garbage collection, green environmental consumption and resources saving, altruism and decision-making, allowance management and impulse buying, consumer's damage salvation, and consciousness of consumer. The total variance was 59.1%. Cronbach's alpha for the seven factors ranged from .77-.88. Finally, a scale measuring the effect of consumer education consisting of 76 items (consumer knowledge: 23 items (9 factors), consumer attitude: 26 items (5 factors), consumer behavior: 27 items (7 factors)) was constructed.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.11
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• pp.81-87
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• 2018

Among various types of geothermal heat pump systems, Vertical Closed-Loop Geothermal Heat Pump (VGSHP) has received increasing attention due to a variety of advantages such as the potential to be installed in a relatively small space and improved energy efficiency. In this research, the performance of VGSHP system coupled with heat storage tank was evaluated, by analyzing operational behavior of heat storage tank, the variations of heat pump energy performance due to the connection with heat storage tank, part load ratios characteristics of heat pump and the corresponding energy cost, compared to chiller and boiler based conventional system. The results of this study showed that the VGSHP system coupled with heat storage tank showed an energy saving effect of about 18% for cooling and about 73% for heating, and annual heating/cooling energy cost reduction of 43,000,000 KRW ($ 39,000), compared to the conventional air conditioning system. In addition, after considering both energy cost and initial investment cost including equipment, installation and auxiliary device expenses, payback period of approximately 11.8 years was required.

• Asian Journal for Public Opinion Research
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• v.2 no.3
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• pp.172-195
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• 2015

Multiple nationwide opinion surveys, carried out by the government (cabinet office), major media (national newspapers and NHK), the National Institute for Environmental Studies, and the Atomic Energy Society of Japan, have revealed that the Fukushima nuclear accident has heightened people's perception of disaster risks, fear of nuclear accidents, and increased recognition of pollution issues, and has changed public opinion on nuclear energy policy. The opinion gap on nuclear energy policy between specialists and lay people has widened since the disaster. The results of the Japanese General Social Survey data show that objections to the promotion of nuclear energy are strong among females, and weaker among young males and the supporters of the LDP. These findings are similar to the data collected after the Chernobyl accident. People who live in a 70km radius of nuclear plants tend to evaluate nuclear disaster risks higher. Distance from nuclear plants and the perception of earthquake risk interactively correlate with opinions on nuclear issues. Among people whose evaluation of earthquake risk is low, those who live nearer to the plants are more likely to object to the abolishment of nuclear plants. It was also found that the nuclear disaster has changed people's behavior; they now try to save electricity. The level of commitment to energy saving is found to relate to opinions on nuclear issues.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.04a
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• pp.56-62
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• 2000

Semi-solid forming process has some advantages such as successful manufacturing of high quality components with less inner defects suitable for less machining high productivity and energy-saving effect. the thixotropic behavior(solid-like in the unperturbed state and liquid-like during shearing) has been the basis for the semi-solid forming process. The main focus of this article is the investigation of the effect of T6 heat treatment and alloying elements on the mechanical properties in the semi-solid formed products using thixotropic hypoeutectic (A357 and ALTHIX 86S) and hypereutectic(A390) materials. The new methods to produce semi-solid formed components with high quality are also proposed and discussed in terms of a die design and the development of a lubricant.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.175-176
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• 2009

Energy saving and environment-friendly dyeing method of cotton with reactive dyes is the ultra low liquor ratio dyeing because it reduces the total quantity of water, dye, salt and alkali during the dyeing process in the effluent as well as the energy consumption. However, this method may not guarantee the quality of the dyeing results due to the specs or unlevel dyeing depending upon the dyes used. The study has focused on the effect of leveling agents in the dyeing of cotton with reactive dyes under the ultra low liquor ratio (1:5). Especially Sunfix N/B MF-D which was selected for ULLR showed low-leveled dyeing comparing with the other MF-D series. A leveling agent having polycarbonate structure increased LDF values of Sunfix N/B MF-D without changing of dyeing fastness. We recommend some leveling agents to improve the leveling behavior for ULLR dyeing.

• Asia Pacific Journal of Business Review
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• v.2 no.2
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• pp.1-15
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• 2018

The purpose of this paper is to find out the factors responsible for purchase of LED (light-emitting-diodes) bulbs & tubes among Indian consumers and how much they are ready to replace their existing lighting system with LED fittings. A multiple regression model has been employed to investigate the factors affecting the buying decision of LED lamps in place of CFL and incandescent lamps. Eleven motives for adopting LED lamps has been identified viz. price, quality, energy saving, durability, brand, promotion, CSR, & environmental consciousness. In addition the effect of demographic variables like gender, age, household income on the purchasing decision of LED has also been examined. A total 150 respondents were contacted visiting different outlet of electrical shops of Northern Delhi. The study may helpful for the companies to decide their marketing strategies to promote LED Lamps among the consumers with an aim to save energy and save environment.

• Journal of Environmental Science International
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• v.20 no.5
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• pp.631-638
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• 2011

The sense of crisis on seriousness of earth environment is gradually getting greater and the importance of environment education followed by this trend is being highlighted. As an environment friendly New Environmental Paradigm opposed to the human Dominant Social Paradigm on the existing environment is on the rise, the environment education considers not only the perceptive field, but the definitive field and behavioral pattern to follow as important values. Accordingly, the basic awareness of students on environment was found out in order to perform a proper environment education and tried to find out the behavior pattern that the students have on environment on this basis. For the research tool of this study, the one that has revised the Revised NEP Scale for elementary school students which Geum, Ji Hun Kim, Jin Mo have validated the feasibility and reliability while the test paper was prepared by dividing into recycling behavior, energy preservation behavior and source of information. The target of this study was 600 students in sixth grade of elementary school residing in Kimhae, Gyeongsangnamdo while the mean, average, standard deviation, independent t-test and correlation analysis were performed using SPSS 15.0 statistics program for a total of 462 copies including 235 copies from male students and 227 copies from female students. The results of this study are as follows. First, everyone had high pro-NEP tendencies on the environmental problem with 4.14. On the other hand, the anti-NEP did not have high awareness standard with 2.98. Second, the awareness level on resource recycling was shown as being quite high with 4.05. Between NEP and resource recycling, a positive correlation of r=.155 was shown so that the awareness level on resource recycling was getting quite high as the awareness on environment problem was getting higher. Third, the awareness level on energy saving activity was shown as being very high with 3.0. Between NEP and resource recycling, a positive correlation of r=.210 so that the awareness level on energy saving was getting quite high as the awareness on environment problem was getting higher. Fourth, for the source of information on environmental problems of region, our country and global village, the television and internet were shown as main sources of information while the ratio of positive answers on teachers and region as sources of information was shown as quite low.