• Title/Summary/Keyword: economic cycle

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TECHNICAL RATIONALE FOR METAL FUEL IN FAST REACTORS

  • Chang, Yoon-Il
    • Nuclear Engineering and Technology
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    • v.39 no.3
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    • pp.161-170
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    • 2007
  • Metal fuel, which was abandoned in the 1960's in favor of oxide fuel, has since then proven to be a viable fast reactor fuel. Key discoveries allowed high burnup capability and excellent steady-state as well as off-normal performance characteristics. Metal fuel is a key to achieving inherent passive safety characteristics and compact and economic fuel cycle closure based on electrorefining and injection-casting refabrication.

Optimization Process Models of Gas Combined Cycle CHP Using Renewable Energy Hybrid System in Industrial Complex (산업단지 내 CHP Hybrid System 최적화 모델에 관한 연구)

  • Oh, Kwang Min;Kim, Lae Hyun
    • Journal of Energy Engineering
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    • v.28 no.3
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    • pp.65-79
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    • 2019
  • The study attempted to estimate the optimal facility capacity by combining renewable energy sources that can be connected with gas CHP in industrial complexes. In particular, we reviewed industrial complexes subject to energy use plan from 2013 to 2016. Although the regional designation was excluded, Sejong industrial complex, which has a fuel usage of 38 thousand TOE annually and a high heat density of $92.6Gcal/km^2{\cdot}h$, was selected for research. And we analyzed the optimal operation model of CHP Hybrid System linking fuel cell and photovoltaic power generation using HOMER Pro, a renewable energy hybrid system economic analysis program. In addition, in order to improve the reliability of the research by analyzing not only the heat demand but also the heat demand patterns for the dominant sectors in the thermal energy, the main supply energy source of CHP, the economic benefits were added to compare the relative benefits. As a result, the total indirect heat demand of Sejong industrial complex under construction was 378,282 Gcal per year, of which paper industry accounted for 77.7%, which is 293,754 Gcal per year. For the entire industrial complex indirect heat demand, a single CHP has an optimal capacity of 30,000 kW. In this case, CHP shares 275,707 Gcal and 72.8% of heat production, while peak load boiler PLB shares 103,240 Gcal and 27.2%. In the CHP, fuel cell, and photovoltaic combinations, the optimum capacity is 30,000 kW, 5,000 kW, and 1,980 kW, respectively. At this time, CHP shared 275,940 Gcal, 72.8%, fuel cell 12,390 Gcal, 3.3%, and PLB 90,620 Gcal, 23.9%. The CHP capacity was not reduced because an uneconomical alternative was found that required excessive operation of the PLB for insufficient heat production resulting from the CHP capacity reduction. On the other hand, in terms of indirect heat demand for the paper industry, which is the dominant industry, the optimal capacity of CHP, fuel cell, and photovoltaic combination is 25,000 kW, 5,000 kW, and 2,000 kW. The heat production was analyzed to be CHP 225,053 Gcal, 76.5%, fuel cell 11,215 Gcal, 3.8%, PLB 58,012 Gcal, 19.7%. However, the economic analysis results of the current electricity market and gas market confirm that the return on investment is impossible. However, we confirmed that the CHP Hybrid System, which combines CHP, fuel cell, and solar power, can improve management conditions of about KRW 9.3 billion annually for a single CHP system.

Analysis on Korea's Economic Volatility: Focusing on the Role of the Service Industry (우리나라 경기변동의 안정성 분석: 서비스산업의 역할을 중심으로)

  • LEE, Jaejoon
    • KDI Journal of Economic Policy
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    • v.33 no.2
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    • pp.1-39
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    • 2011
  • This study discusses the phenomenon behind various forms of macroeconomic volatility faced by countries in terms of industrial structure through empirical analysis, and in the process attempts to validate the role of the service industry. The analysis shows that economic fluctuations in Korea have been significantly improved, mainly due to the country risk. However, Korea is still exposed to the impact of external shocks, which is attributable to the manufacturing-centered industrial structure. Under such industrial structure, it is inevitable for the Korean economy to be continuously exposed to macroeconomic fluctuations caused by global sectoral shocks. So, in order to alleviate business fluctuations, it is necessary to enhance the role of non-tradable sectors that account for most of the service industry.

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The Relationship between the State of the Economy and High Heel Height - Based on Pump Style Shoes on Fashion Editorial Section of US Vogue - (경제와 여성 구두 굽 높이 변화의 관계 - 미국 Vogue 패션편집란에 실린 펌프스타일을 중심으로 -)

  • Ahn, Insook
    • Journal of the Korean Society of Costume
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    • v.65 no.7
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    • pp.86-100
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    • 2015
  • This study is to investigate the relationships between heel height and macro-economic factors - recession and unemployment; and to analyze the time lags reflecting economic factors on heel height index using U.S. data. The life-history evolution theory was applied to propose the relationships studied. The data for the heel height measurements of women's shoes - pump style only - were obtained from US Vogue fashion editorial sections on spring and fall editions from 1950 to 2014. I divided the heel height by the length of the shoes in order to standardize the data. Total of 1581 samples were used, and heel height data were aggregated to create a yearly average. To explore the relationships between macro-economic factors and heel height, this study used OLS of Stata 13 program. The main findings show that unemployment rates influenced heel height for three years in a positive direction. Furthermore, the effects of unemployment rate from two years ago on the current heel height were very close to being on a significant level.

Application of the Intensity of Use of Mineral Consumption Forecasting (광물자원(鑛物資源) 수요예측(需要豫測) 모형(模型)으로서의 사용강도(使用强度) 방법(方法) 응용(應用))

  • Jeon, Gyoo Jeong
    • Economic and Environmental Geology
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    • v.23 no.4
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    • pp.383-392
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    • 1990
  • This study found that that dynamics of intensity of use and economic theory of derived demand can both be accommodated through an extensive translog demand model. The basic idea in this recognition is that the skewed life cycle empirical pattern of intensity of use plotted against per capita income is of lognormal form and this lognomal intensity of use model can be mathematically transformed into an eqivalent simple translog intensity of use model. Empirical results showed that this extensive traslog model, which is a flexible function and includes both the classical case of fixed coefficients and the dynamic case of varying coefficients of the explanatory variables, gave better forecasts than the original intensity of use model and other conventional models.

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Firm's Economic Efficiency and Critical Weather Information in Distribution Industry by Climate Change (기후변화에 따른 유통산업의 핵심 기상요인과 기업의 경제적 효율성)

  • Lee, Joong-Woo;Ko, Kwang-Kun;Jeon, Jin-Hwan
    • Journal of Environmental Science International
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    • v.19 no.6
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    • pp.787-797
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    • 2010
  • Nowadays meteorological information is systemized as a useful knowledge which has a significant effect on the overall industrial domains over the simple data. The distribution industry, which has the short life cycle, depends on the meteorological information at the strategic level. However, it is necessary to pay attention to the continuous investment in meteorological information because there is a hostility to paying for a service, particularly it does not provide accurate and reliable information. Therefore, the purpose of this study is to increase the usefulness of meteorological information in the distribution industry for its economic effectiveness from the core meteorological factors. We found significant meteorological factors (temperature, precipitation, disaster) that have a critical influence on the distribution industry through the hierarchical analysis process, and their importance according to the type of distribution channels, such as department store, large-scale discount store, convenience store, and home shopping. We performed the AHP analysis with 103 survey samples by middle managers from the various distribution channels. We found that precipitation is the critical meteorological factor across the distribution industry. Based on this result, we stress the difference in the level of the meteorological information in order for the effectiveness of each type of distribution channels.

Economic analysis of biomass torrefaction plants integrated with corn ethanol plants and coal-fired power plants

  • Tiffany, Douglas G.;Lee, Won Fy;Morey, Vance;Kaliyan, Nalladurai
    • Advances in Energy Research
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    • v.1 no.2
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    • pp.127-146
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    • 2013
  • Torrefaction technologies convert assorted biomass feedstocks into energy-concentrated, carbon neutral fuel that is economically transported and easily ground for blending with fossil coals at numerous power plants around the world without needs to retrofit. Utilization of torrefied biomass in conventional electric generating units may be an increasingly attractive alternative for electricity generation as aging power plants in the world need to be upgraded or improved. This paper examines the economic feasibility of torrefaction in different scenarios by modeling torrefaction plants producing 136,078 t/year (150,000 ton/year) biocoal from wood and corn stover. The utilization of biocoal blends in existing coal-fired power plants is modeled to determine the demand for this fuel in the context of emerging policies regulating emissions from coal in the U.S. setting. Opportunities to co-locate torrefaction facilities adjacent to corn ethanol plants and coal-fired power plants are explored as means to improve economics for collaborating businesses. Life cycle analysis was conducted in parallel to this economic study and was used to determine environmental impacts of converting biomass to biocoal for blending in coal-fired power plants as well as the use of substantial flows of off-gasses produced in the torrefaction process. Sensitivity analysis of the financial rates of return of the different businesses has been performed to measure impacts of different factors, whether input prices, output prices, or policy measures that render costs or rewards for the businesses.

A Study on the Adequate Capacity of Substation Transformer for Offshore Wind Farm (해상풍력발전단지의 해상변전소 변압기 적정 용량에 관한 연구)

  • Moon, Won-Sik;Jo, Ara;Huh, Jae-Sun;Bae, In-Su;Kim, Jae-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.8
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    • pp.83-89
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    • 2015
  • This study suggests the methodology to decide the number and adequate capacity of substation transformer in a large-scale offshore wind farm (OWF). The recent trend in transformer capacity of offshore substation is analyzed in many European offshore wind farm sites prior to entering the studies. In order to carry out the economic evaluation for the transformer capacity we present the cost models which consist of investment, operation, and expected energy not supplied (EENS) cost as well as the probabilistic wind power model of wind energy that combines the wind speed with wind turbine output characteristics for a exact calculation of energy loss cost. Economic assessment includes sensitivity analysis of parameters which could impact the 400-MW OWF: average wind speed, availability, discount rate, energy cost, and life-cycle.

ARIMA Based Wind Speed Modeling for Wind Farm Reliability Analysis and Cost Estimation

  • Rajeevan, A.K.;Shouri, P.V;Nair, Usha
    • Journal of Electrical Engineering and Technology
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    • v.11 no.4
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    • pp.869-877
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    • 2016
  • Necessity has compelled man to improve upon the art of tapping wind energy for power generation; an apt reliever of strain exerted on the non-renewable fossil fuel. The power generation in a Wind Farm (WF) depends on site and wind velocity which varies with time and season which in turn determine wind power modeling. It implies, the development of an accurate wind speed model to predict wind power fluctuations at a particular site is significant. In this paper, Box-Jenkins ARIMA (Auto Regressive Integrated Moving Average) time series model for wind speed is developed for a 99MW wind farm in the southern region of India. Because of the uncertainty in wind power developed, the economic viability and reliability of power generation is significant. Life Cycle Costing (LCC) method is used to determine the economic viability of WF generated power. Reliability models of WF are developed with the help of load curve of the utility grid and Capacity Outage Probability Table (COPT). ARIMA wind speed model is used for developing COPT. The values of annual reliability indices and variations of risk index of the WF with system peak load are calculated. Such reliability models of large WF can be used in generation system planning.

A Study on Economic Value of Korean Private Universities' Profitable Business Based on Successful and Failed Cases

  • LEE, Choon-Ho
    • The Journal of Economics, Marketing and Management
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    • v.9 no.4
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    • pp.9-18
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    • 2021
  • Purpose: This study examines some successful and failed cases of Korean private universities' profitable business and explores the desirable economic value and direction of their profitable business business operations with a view to shedding light on some clues conducive to their financial health and quality education. Research design, data and methodology: This study reviews news articles, reports and literature to find out Korean universities' financial condition and examines some successful and failed examples of their corporations' profit-making business operations to suggest a direction. Results: Private universities suffer declining enrollments and/or tuition freeze but they lack in making efforts to secure financial health. The reviewed examples of private universities' profit-making business operations suggest both universities and their corporations should first assume the public accountability prior to engaging in diverse business activities. Conclusions: First, to remain financially healthy, university corporations should exert themselves to transform their low-profit-margin lands and buildings into high-profit-margin businesses and to credit the realized income to their school-expense accounts. And, the ultimate purpose of universities' profit-making business operations is to realize a decent income without prejudice to their public accountability for the country and community, while forging a virtuous cycle by investing the income for the betterment of their educational quality and competitiveness.