• KIEAE Journal
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• v.17 no.3
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• pp.45-50
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• 2017

Purpose: There have been more researches focused on eco-friendly construction practices in order to save energy consumed and these practices have been extensively applied for constructing buildings. However, researches on energy consumption saving and efficiency for hospital facilities have been still insufficient. This research aims to draw factors that affect energy efficiency of hospital buildings through literature reviews and perform an expert-survey using AHP(Analytical Hierarchy Process) method in order to analyze the importances and priorities of these energy efficient factors. Method: Using the AHP method, this paper suggests the importances and priorities of factors to affect energy efficiency in hospital buildings. The survey of experts at a architectural design and a construction management companies was conducted via e-mail and mail. Result: As a result, factors of window and door, insulation, ventilation, and natural lighting turned out relatively important as respectively 0.104, 0.102, 0.101, and 0.095 n the energy efficiency in hospital buildings, while factors of artificial lighting, geothermal, solar heat, and control did unimportant as 0.027, 0.033, 0.043, and 0.053.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.3
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• pp.67-81
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• 2004

This research demonstrates clothing consumption values, fashion preferences of career women from the early 1920s to late 1930s. And having thorough understanding of values and preferences, allows us to establish marketing strategies for clothing companies. The main purpose of this study is (1) to formalize consumer group based upon the clothing consumption values, (2) to find for characteristics of consumer depending on classification of consumption value in clothing, (3) to understand the preferences of career women about fashion trends. Analyzing data was performed 292 copies, resulting factor analysis, Cluster analysis, X-test, Anova, Tukey test, t-test, frequency analysis, and reliability analysis. This paper showed 7 distinctive characteristics of career women about clothing consumption value. These characteristics can be listed as 1) value of brand image, 2) value of self-expression, 3) functional values, 4) epistemic values, 5) coordination values, 6) social values 7) psychological values. Importantly, brand image value became most significant aspects among 7 factors. Analyzing consumers based upon stated 7 factors, it was found that they are segregated into 4 groups; Self-expressive Group, Psychological Stability Group, Functional Group, Social Group. Secondly, for fashion trend preferences, self-expressive group, psychological stability group, and functional group favored Romantic Feminine Style respectively. Social Group showed preference in Nu-Basic'. The reason for such trend dealt with fabric materials and colors. Finally examining population statistics, younger generations showed more preferences in Nu-Basic', and consumers from ages of 26 to 28, 32 to 34 showed preferences in Romantic Feminine' regardless of their household income, clothing related expenditures, jobs, and education level. On the other hand, 'Modem Classic' was popular among college graduates and 'Paradise' was somewhat less popular among all ages except from ages of 32 to 34, consumers consumption 300,000Won to 400,000Won on clothing related expenditures. And 'Energy' seemed to attract more highly educated females, who had more than masters in degrees with over 300,000 to 400,000Won for clothing related expenditures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.168-174
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• 2001

This study was conducted to investigate correlation between soybean and their products consumption and risk factors for atherosclerosis in the healthyKorean adults. Health behaviors such as smoking, exercise, alcohol consumption and dietary patterns and nutrient intakes of 193 healthy adult subjects aged from 26 to 69 were assessed by using interview and semiquantitative food frequency questionnaire. The BMI, blood pressure and biochemical parameters of blood were examined as well as preferences for taste and family history of disease. Data were expressed as quartile according to soybean and their products consumption. The average daily soybean and their product consumption for 1st, 2nd, 3rd, and 4th percentile group were 36, 78, 112, and 182g, respectively. The more consumption of soybean and their products, the more intake of energy, protein, lipid, fiber, Ca, cholesterol as well as frequency of exercise, smoking and drinking. Serum TG, total cholesterol and LDL-cholesterol and AI as risk factors of atherosclerosis were positively correlated with smoking and drinking (p<0.05). Especially, serum TG was positively correlated with hypertension and BMI (p<0.01). But, no correlation between exercise, salty taste, meat preference, soybean products consumption and atherosclerosis risk factors was found, which means that life styles such as smoking and drinking rather than dietary habits might influence atherosclerosis in healthy adults. In conclusion, present soy products consumption should be increased by way of developing new generation soy products in order to exert anti-atherosclerotic effect by soybean in human.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.7
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• pp.1039-1046
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• 2017

Campus microgrid is designed and built by considering not only power generation but also power consumption management as connected microgrid type because the main goal of the campus microgrid is to save power consumption costs. There are many functions to achieve the goal and they are mainly to use generation-based functions such as islanding operation for peak management and for emergency events. In power distribution operation, Conservation Voltage Reduction (CVR) is applied in order to reduce power consumption. The CVR is defined as a function for load consumption reduction by voltage reduction in order to reduce peak demands and energy consumption. However, application of CVR to microgrid is difficult because the microgrid cannot control a tap of transformer in a substation and the microgrid normally is not designed with phase modifying equipment like a step-voltage-regulator which can control voltage in power distribution system operation. In addition, an impact of the CVR is depended on load characteristics such as a normal load, a rated power, and synchronous motors. Therefore, this paper proposes an application of CVR using linear voltage control based AVR in campus microgrid with power consumption reduction considering characteristics of load and component in the microgrid. The proposed system can be applied to each buildings by a configuration of power distribution cables; and the application results and CVR factor are presented in this paper.

• Journal of Mechanical Science and Technology
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• v.19 no.12
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• pp.2321-2329
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• 2005

One means of fulfilling $CO_2$ emission legislation is to downsize engines by boosting their power using turbochargers or mechanical superchargers. This reduces fuel consumption by decreasing the engine displacement. When a turbocharger, which is preferable to a mechanical supercharger in terms of fuel efficiency, is used, there is insufficient availability of exhaust gas energy at low engine speeds, resulting in an unfavorable engine response. Therefore, mechanically driven superchargers have increased in popularity due to their quick response to changing speeds in the transient phase. However, since a mechanical supercharger obtains its driving power from the engine, it is difficult to decrease its fuel consumption. This remains a large negative factor for superchargers, despite their excellent dynamic performance. This study aims to develop a power control concept to improve the fuel economy of a mechanical screw supercharger, which could then be used for engine downsizing.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.4
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• pp.287-296
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• 2006

In this paper, optimal control strategy of the air-conditioning system with slab thermal storage was investigated based on the optimal control theory. An optimal heat output to the plenum chamber and the air-conditioned room was determined based on two kinds of criterion functions. The first one requires small deviation in room air temperature from a set-point value and low energy consumption. It is shown that the optimized control is to store heat through the whole storage time and to increase storage rate gradually with time. As the second case, a criterion that both a deviation of operative temperature from a set-point temperature and the energy consumption should be minimized was adopted. The room air temperature was a little high and the cooling load during storage time was reduced, compared with the results when a criterion function considering only the room air temperature is used.

• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.1
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• pp.49-67
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• 2014

This paper proposes a real time pricing model for smart grid considering consumers' behavior, real time price elasticity, and exogenous price. Based on the proposed model, we found the weight of utility over cost is the most sensitive factor compared to other factors. Also, if the electricity price is set to be changed too sensitively to energy consumption, it is warned that real time pricing sometimes can cause increment of peak-time demand and volatility. Finally, real time pricing could be less efficient when the difference between the maximum and the minimum consumption level is small.

• KIEE International Transactions on Power Engineering
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• v.5A no.2
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• pp.109-115
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• 2005

Recently, the needs and concerns regarding power loss have been increasing according to energy conservation at the level of the national policies and the business strategies of power utilities. In particular, the issue of power loss is the main factor for determining rates for electrical consumption in the deregulation of the electrical industry. However, because of the lack of management for power loss load factors (LLF) it is difficult to make a calculation for power loss and to make a decision concerning the electric rates. Furthermore, loss factor (k-factor) in Korea, which is of primary significance in the calculation of distribution power loss, has been used as a fixed value of 0.32 since the fiscal year 1973. Therefore, this study presents the statistical calculation methods of the loss factors classified by load types and seasons by using the practical data of 65 primary feeders that have been selected by appropriate procedures. Based on the above, the algorithms and methods, as well as the optimal method of the distribution loss management classified by facilities such as primary feeders, distribution transformers and secondary feeders is presented. The simulation results demonstrate the effectiveness and usefulness of the proposed methods.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.177-182
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• 2009

The purpose of this study is to investigate planning of urban energy supply systems configuration and operating conditions for the district heating and cooling system using combined heat and power system. Generally the district heating and cooling system has been known to one of the effective way for energy saving, cost reduction and demand side management of energy. Economical analyses were carried out and operating characteristics for some systems were examined in terms of GER factor which represents to the ratio of gas and electricity costs. Rates of the energy consumption and the $CO_2$ emission were compared from the system configuration of the energy supply system with new district cooling system with the conventional one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.351-357
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• 2022

A conventional seawater reverse osmosis (SWRO) and a forward osmosis (FO) and reverse osmosis (RO) hybrid process to produce 1,000 m³/d of fresh water, were designed and compared in terms of carbon emission. When FO was adapted for the osmotic dilution, the required pressure for RO decreases, and thus energy consumption decreases. The decrease in carbon emission by decreased energy consumption (up to -0.73 kgCO₂/m³ using coal as the energy source) was compared with the increase in carbon emission by the FO system (+0.16 kgCO₂/m³), which is a function of various factors such as the number of FO modules and energy consumption. The comparison revealed that the FO-RO process causes less carbon emission compared with the SWRO process when the energy sources are coal and oil. However, if energy sources with low carbon emission such as solar, wind, and nuclear energy are selected, the carbon emission of the FO-RO process becomes higher than that of the SWRO process. This implies that the type of energy source is a key factor to determine the necessity of the FO-RO process from the aspect of carbon emission.