• Title/Summary/Keyword: Power economics

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A Study on the Family Life Value of Middle and High School Students (중고등학생의 가정생활 가치관에 관한 연구)

  • 한정희;최동숙
    • Journal of Korean Home Economics Education Association
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    • v.7 no.1
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    • pp.11-27
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    • 1995
  • The purpose of this research is to study the middle and high school student’s value on the family life of the contemporary society. The data for this study has been collected for 808 students of kangwon-do by Liert-scale Type questionnaire. The data were processed by SPSS-X Program. Frequency, Percentage, Mean, Standard Deviation, One-way ANOVA, Pearson’r coefficient, Step-wise multiple regression and Cronbach’coefficient have been calculated and analyzed. The Summary of this research is described as follows. Firstly, the overall average of value of family life was 3.25 points which reflected more or less modern tendency. Secondly, significant difference in the student’s value of family life affected by environmental variables were such as sex(P<.001) school years(P<.001) group(P<.01). Thirdly, the overall average of the student’s interest in the home economics was 3.74 points which reflected heigher tendency, Significant difference in the student’s interest in the home economics according to environmental variables were such as sex(P<.001) school years(P<.05), living standard(P<.01), residential area(P<.001). Fourthly, the student’s overall interest in the home economics and their view on the family life were correlated as follows; Spare time(r=-1.3), parents-children(r=.12) relatives and neighbors(r=0.8) show lower correlation and household work(r=.07) show higher correlation. Fifthly, the area which has closest correlation with the value on the family life was the value on family economics, whereas is has been shown that the field with least correlation was the area of supporting the spare time. Sixthly changes that affect the student’s value of the family life were such as sex (${\beta}$=.43), school years(${\beta}$=.18), group(${\beta}$=.15) and interest degrees(${\beta}$=-.12). These whole explanatory power was 21%.

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Recommended Practice for the Improvement of the Unit Cost of Power Consumption in Non-utility Electrical Installation (자가용전기설비의 전력원단위 향상을 위한 전력관리 방안)

  • 김세동
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2000.11a
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    • pp.235-240
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    • 2000
  • This paper presents the reasonable method for electric power management through efficient use of electricity. With a rapid of national economics and living standard, electrical energy consumption markedly increased. Especially it is increased electrical energy consumption in commercial buildings and thus an energy conservation through efficient use of electricity became more important.

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FINITE GROUPS WITH A CYCLIC NORM QUOTIENT

  • Wang, Junxin
    • Bulletin of the Korean Mathematical Society
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    • v.53 no.2
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    • pp.479-486
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    • 2016
  • The norm N(G) of a group G is the intersection of the normalizers of all the subgroups of G. In this paper, the structure of finite groups with a cyclic norm quotient is determined. As an application of the result, an interesting characteristic of cyclic groups is given, which asserts that a finite group G is cyclic if and only if Aut(G)/P(G) is cyclic, where P(G) is the power automorphism group of G.

THE DESIGN FEATURES OF THE ADVANCED POWER REACTOR 1400

  • Lee, Sang-Seob;Kim, Sung-Hwan;Suh, Kune-Yull
    • Nuclear Engineering and Technology
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    • v.41 no.8
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    • pp.995-1004
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    • 2009
  • The Advanced Power Reactor 1400 (APR1400) is an evolutionary advanced light water reactor (ALWR) based on the Optimized Power Reactor 1000 (OPR1000), which is in operation in Korea. The APR1400 incorporates a variety of engineering improvements and operational experience to enhance safety, economics, and reliability. The advanced design features and improvements of the APR1400 design include a pilot operated safety relief valve (POSRV), a four-train safety injection system with direct vessel injection (DVI), a fluidic device (FD) in the safety injection tank, an in-containment refueling water storage tank (IRWST), an external reactor vessel cooling system, and an integrated head assembly (IHA). Development of the APR1400 started in 1992 and continued for ten years. The APR1400 design received design certification from the Korean nuclear regulatory body in May of2002. Currently, two construction projects for the APR1400 are in progress in Korea.

A Stochastic Analysis of a Wind Power Investment (풍력자원의 불확실성을 고려한 사업자측면에서의 투자타당성)

  • Lee, Jae-Gul;Park, Min-Hyug;Lee, Yun-Kyoung;Kim, Jung-Ju
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.357-360
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    • 2007
  • Any investment analysis has to deal with the uncertainty that arises over the course of operating the invested project. When it comes to an wind power, such analysis gets even more complicated, as the wind resource or the current is inherently unstable and unpredictable. Different from predecessors in the field of analyzing wind power economics, this paper proposes a stochastic methodology of analyzing the economic efficiency of an investment in wind power to explicitly address those uncertainties or risks. A probability distribution is assigned to each variable to generate a probability distribution of the economic value of an investment through a Monte-Carlo simulation

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The Relationship between Interdependence on Relational Satisfaction in Cosmetics Distribution Channels: Moderating Effect of Communication and Mediating Effect of Non-coercive Power

  • Sun, Il-Suck;Yang, Hoe-Chang
    • The Journal of Economics, Marketing and Management
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    • v.4 no.1
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    • pp.9-22
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    • 2016
  • This study tried to examine how interdependence, communication, and the exercise of power in cosmetics distribution channel would affect satisfaction. In this study we investigated the effects of their communication and the exercise of noncoercive power of department store (or mart). We conducted with managers of the shops which were entered to department store (or mart). 131 copies were collected and 119 copies were used for analysis after the exclusion of 12 copies. Brand image and sales policy influenced satisfaction, but customers were not statistically significant. In addition, communication in distribution path had the moderating effect on the relationship between interdependence and satisfaction, and on the relationship between interdependence and noncoercive power. Sales policy and brand image in the relationship between department store(or mart) and the shops opened inside are critical factors for satisfaction, but customers are highly likely to become a factor with different meaning.

Impacts of Wind Power Integration on Generation Dispatch in Power Systems

  • Lyu, Jae-Kun;Heo, Jae-Haeng;Kim, Mun-Kyeom;Park, Jong-Keun
    • Journal of Electrical Engineering and Technology
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    • v.8 no.3
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    • pp.453-463
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    • 2013
  • The probabilistic nature of renewable energy, especially wind energy, increases the needs for new forms of planning and operating with electrical power. This paper presents a novel approach for determining the short-term generation schedule for optimal operations of wind energy-integrated power systems. The proposed probabilistic security-constrained optimal power flow (P-SCOPF) considers dispatch, network, and security constraints in pre- and post-contingency states. The method considers two sources of uncertainty: power demand and wind speed. The power demand is assumed to follow a normal distribution, while the correlated wind speed is modeled by the Weibull distribution. A Monte Carlo simulation is used to choose input variables of power demand and wind speed from their probability distribution functions. Then, P-SCOPF can be applied to the input variables. This approach was tested on a modified IEEE 30-bus system with two wind farms. The results show that the proposed approach provides information on power system economics, security, and environmental parameters to enable better decision-making by system operators.

Portfolio Analysis on the New Power Generation Sources of the Sixth Basic Plan for Long Term Electricity Demand and Supply (포트폴리오 이론을 활용한 제6차 전력수급기본계획의 신규전원구성 비교 연구)

  • Kim, Juhan;Kim, Jinsoo
    • Environmental and Resource Economics Review
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    • v.23 no.4
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    • pp.583-615
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    • 2014
  • Including the rolling black out in 2011, Korea has suffered from rapid increase of electricity consumption and demand forecasting failure for last five years. In addition, because of the Fukushima disaster, high fuel prices, and introduction of new generation sources such as renewables, the uncertainty on a power supply strategy increases. Consequently, a stable power supply becomes the new agenda and a revisino of strategy for new power generation sources is needed. In the light of this, we appraises the sixth basic plan for long term electricity demand and supply considering the changes of foreign and domestic conditions. We also simulate a strategy for the new power generation sources using a portfolio analysis method. As results, a diversity of power generation sources will increase and the share of renewable power generation will be surged on the assumptions of a cost reduction of renewable power sources and an increase of fuel costs. Particularly, on the range of a risk level(standard deviation) from 0.06 and 0.09, the efficient frontier has the most various power sources. Besides, the existing power plan is not efficient so that an improvement is needed. Lastly, the development of an electricity storage system and energy management system is necessary to make a stable and efficient power supply condition.

Evaluation of Technical Production Efficiency and Business Structure of Domestic Combined Heat and Power (CHP) Operators: Panel Stochastic Frontier Model Analysis for 16 Collective Energy Operators (국내 열병합발전사업의 기술적 생산효율성 추정 및 사업구조 평가: 16개 집단에너지사업자에 대한 패널 확률프론티어모형(SFA) 분석)

  • Lim, Hyungwoo;Kim, Jaehyeok;Shin, Donghyun
    • Environmental and Resource Economics Review
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    • v.30 no.4
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    • pp.557-579
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    • 2021
  • Collective energy is an intermediate stage in energy conversion and has a great influence on the power structure as a distributed power source. However, the problem of the collective energy business has recently emerged due to the worsening profitability of some collective energy operators. This study measured the technical efficiency of major operators through the estimation of the production efficiency of Korean collective energy operators, and based on this, we looked at ways to improve the profit structure of operators. After collecting detailed data from 16 collective energy operators between 2016 and 2019, the production efficiency of operators was estimated using the panel stochastic frontier model. As a result of the estimation, combined steam power operators showed the highest production efficiency and reverse CHP operators showed the lowest efficiency. Furthermore, as a result of examining the factors influencing profitability, it was confirmed that production efficiency has a positive effect on overall profitability. However, businesses with a high proportion of heat production, such as small district electricity operators, profitability was lower. This phenomenon is due to the structural limitations of the current heat sales market. Hence, the adjustment of the heat sales unit price is necessary to improve profitability of collective energy operators.

Development of the scale for recognition measurement of Home Economics Subject (가정교과의 인식 측정을 위한 척도 개발 연구)

  • Baek, Min-Kyung;Wang, Seok-Soon
    • Journal of Korean Home Economics Education Association
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    • v.24 no.2
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    • pp.101-116
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    • 2012
  • The purpose of this research is to develop a scale to measure how students and parents, who are the consumers of education, and home economics teachers and education experts, who are the suppliers, recognize the home economics subject, based on the characteristics and goal of the revised home economics curriculum that is currently being applied in South Korea, in the year 2007. To do this, the survey on home economics recognition developed and utilized in prior researches was used as the basic data. The final version of 60 questions was made by adding questions made through steps. They include question quality factor verification through step1-interview, step2-draft questions, step3-preliminary research, and step4-substantiation research of four groups. As a result of the factor analysis of the recognition of home economics, credibility is high in all factors. The final scale consists of 8 factors, when the explanatory power is 57.439%. This shows that home economics has been established as education for living and a practical subject. Nevertheless, it needs further improving to be recognized as a subject involving emphasis on healthy formation of family life and a subject of practical criticism.

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