• Title/Summary/Keyword: Energy Budget

Search Result 251, Processing Time 0.024 seconds

Energy transport analysis for the Taylor-Proudman column in la rapidly-rotating compressible fluid (압축성 회전 유동에서의 Taylor-Proudman 기둥의 에너지 전달에 관한 해석)

  • Park Jun Sang;Hyun Jae Min
    • Proceedings of the KSME Conference
    • /
    • 2002.08a
    • /
    • pp.329-332
    • /
    • 2002
  • A theoretical study is made of the steady flow of a compressible fluid in a rapidly rotating finite cylinder. Flow is generated by imposing mechanical and/or thermal disturbances at the rotating endwall disks. Both the Ekman and Rossby numbers are small. A detailed consideration is given to the energy budget for a control volume in the Ekman boundary layer. A combination of physical variables, which is termed the energy contents, consisting of temperature and modified angular momentum, emerges to be relevant. The distinguishing features of a compressible fluid, in contrast to those of an incompressible fluid, are noted. For the Taylor-Proudman column to be sustained, in the interior, it is shown that the net energy transport between the solid disk wall and the interior fluid should vanish. Physical rationalizations are facilitated by resorting to the concept of the afore-stated energy content.

  • PDF

A Study on The Effect of Anthropogenic Heat Flux and Land-Use on Thermal Environment in Pusan (인공열과 land-use가 부산시의 열적 환경에 미치는 영향 연구)

  • 김유근
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.16 no.4
    • /
    • pp.363-372
    • /
    • 2000
  • In order to overtake a quantitative analysis of effect of anthropogenic heat and different land-use on urban thermal environment numerical simulation of surface energy budget was carried out under typical summer synoptic condition. It is beneficial to understand surface temperature of complex urban surace. The different land-use types are classified of rice field farm fruit garden residential region forest water and swamp by using map scaled 1/25000 of Pusan metropolitan. The model predicts that maximum heat island intensity in the central part of Pusan is 7$^{\circ}C$ at 2000 LST in summertime. The surface temperature is propotional to the density of constructions. The effect of anthropogenic heat generation on surface temperature is the increase of 0.3$^{\circ}C$ at 1400LST in the central part of Pusan during summertime.

  • PDF

TMR Contribution Analysis of Spindle-Disk System Vibration for the High-Density Hard Disk Drive of 80GB/Platter (80GB/PLATTER 하드 디스크 드라이브 설계를 위한 스핀들-디스크 시스템 진동의 TMR 기여도 분석)

  • 강성우;한윤식;오동호;황태연;김명업
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2001.11a
    • /
    • pp.58-64
    • /
    • 2001
  • An investigation of the TMR(Track Misregistration) requirements to achieve the capacity of 80GBytes/Platter in 7200rpm disk drive system is reported. This paper also gives an overview of the PES(Position Error Signal) characteristics in the 57,500TPI disk drive to estimate the required 95,000TPI-system PES. The TMR measured by PES are presented and decomposed in order to identify the portions and their contributions of the spindle-disk system vibration and HSA(Head-Stack-Assembly) system vibration respectively. A comprehensive review on the servo system is also presented to provide the practical limits of the modem servo architecture into TMR budget design. The decomposed PES energy distribution shows that the spindle-disk pack vibration is one of the top-ranking sources of the total TMR budget and its percentage contribution is about 50% considering all the other TMR sources.

  • PDF

The Assessment System for DSM Investment Programs by KOGAS & KDHC (천연가스.지역난방 수요관리 투자사업 평가 시스템)

  • Park, Soo-Uk;Lee, Deok-Ki;Kim, Euy-Kyung;Jeon, Ho-Cheol
    • Proceedings of the SAREK Conference
    • /
    • 2008.06a
    • /
    • pp.226-230
    • /
    • 2008
  • DSM Investment Programs are accomplished by KOGAS and KDHC, based on 'Article 15, Rational Energy Utilization Act'. By this act, suppliers are accomlishing DSM Investment Programs with much budget and contribute national DSM. However, there was no assessment systems for the quantitative evaluation of DSM Investment Programs in natural gas and district heating domains, yet. In order to overcome this problem, we constructed the assessment system which select quantitative programs, analyze impact factors, develop logic and equations and computerize this system. With this system, we can give objective and reliable output of DSM Investment Programs and evaluation tool to promote them efficiently. In this paper, we write the development process, method and utilization of this assessment system.

  • PDF

A review of Deepwater Horizon Oil Budget Calculator for its Application to Korea (딥워터 호라이즌호 유출유 수지분석 모델의 국내 적용성 검토)

  • Kim, Choong-Ki;Oh, Jeong-Hwan;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.19 no.4
    • /
    • pp.322-331
    • /
    • 2016
  • Oil budget calculator identifies the removal pathways of spilled oil by both natural and response methods, and estimates the remaining oil required response activities. A oil budget calculator was newly developed as a response tool for Deepwater Horizon oil spill incident in Gulf of Mexico in 2010 to inform clean up decisions for Incident Comment System, which was also successfully utilized to media and general public promotion of oil spill response activities. This study analyzed the theoretical background of the oil budget calculator and explored its future application to Korea. The oil budge calculation of four catastrophic marine pollution incidents indicates that 3~8% of spilled oil was removed mechanically by skimmers, 1~5% by in-situ burning, 4.8~16% by chemical dispersion due to dispersant operation, and 37~56% by weathering processes such as evaporation, dissolution, and natural dispersion. The results show that in-situ burning and chemical dispersion effectively remove spilled oil more than the mechanical removal by skimming, and natural weathering processes are also very effective to remove spilled oil. To apply the oil budget calculator in Korea, its parameters need to be optimized in response to the seasonal characteristics of marine environment, the characteristics of spilled oil and response technologies. A new algorithm also needs to be developed to estimate the oil budget due to shoreline cleanup activities. An oil budget calculator optimized in Korea can play a critical role in informing decisions for oil spill response activities and communicating spill prevention and response activities with the media and general public.

Outcome Analysis on Renewable Energy Dissemination Program through Correlation Analysis and Effectiveness Indicator (상관관계분석, 설비투입액 비교 및 효율성 지표를 통한 신재생에너지보급사업의 정량적 성과분석 고찰)

  • Lee, Dong-Geon;Moon, Chang-Kwon;Heo, Eunn-Yeong
    • New & Renewable Energy
    • /
    • v.6 no.2
    • /
    • pp.33-39
    • /
    • 2010
  • The objective of this study is to present a basis for the evaluation on the renewable energy dissemination program in Korea applying the outcome evaluation, one of the five types of evaluation methods of EERE, DOE, and the effectiveness indicator, which is suggested by IEA, OECD. The outcome evaluation quantifies achievements of program outputs and outcomes against planned time frame. We analyze the correlation coefficients between cumulative expenditure on the renewable energy dissemination program and each renewable energy deployment and the unit installation cost of several dissemination programs for the outcome evaluation. Meanwhile, the effectiveness indicator is calculated by dividing the additional renewable energy deployment achieved in a given year by the remaining mid-term realizable potential to 2020 in each source of renewable energy. The results show that correlation coefficients between cumulative expenditure and each renewable energy deployment are significantly positive during the implementation period of each deployment program. And photovoltaic energy, bio energy, and wind power energy show high effectiveness indicator.

Perspective of Energy Education: Comparison between the Management Group and the Teaching Group (에너지교육에 대한 학교 조직 내 관리집단과 교수집단의 인식 수준 차이)

  • Seo, Eun-Jung
    • Journal of the Korean Solar Energy Society
    • /
    • v.31 no.5
    • /
    • pp.105-112
    • /
    • 2011
  • The purpose of this study was to analyze and compare the management group' and the teaching group' perception of energy education in Korea. For this purpose, this study carried out a questionnaire survey at schools participating in the energy saving policy. The data was collected from six managers and 171 teachers in middle schools. First, the results indicated that both the management group and teachers have a considerable interest in teaching energy saving practice. How ever the management group showed more preference toward teacher-leading courses, such as lecture, compared to the teachers Second, both the management group and teachers tended to take extracurricular activities. Third, the manager group mostly got energy educational resource from the teacher training program, textbook and teacher's companion. However the teachers mostly did from the mass media. Fourth, compared to the teachers, the managers preferred to allot more budgets to school facilities than to activities related to educating students related to energy. Fifth, the management group pointed out curriculum-making and more budget as the necessity to enhance energy education but the teaching groups did students' interest. Sixth, both the management group and teachers emphasis on the need of energy education.

Selecting Strategic Energy Technology R&D Programs Applied to the AHP Approach as Planning a Big-sized Energy R&D Program (대형과제 기획시 계층분석적 의사결정기법을 적용한 전략적 에너지기술 R&D 프로그램 선정)

  • Lee, Seong-Kon;Mogi, Gento;Kim, Jong-Wook
    • New & Renewable Energy
    • /
    • v.4 no.1
    • /
    • pp.25-30
    • /
    • 2008
  • The R&D budget of energy technology development has increased in the sector of korean energy technology development continuously. In addition to that, KIER, the government invested research institute and unique energy technology R&D research institute, is trying to plan for a big-sized energy R&D program for the well focused R&D and excellent research outcomes. In the phase of R&D process, the planning is one of the most important sectors because it drives the direction of R&D. In this study, we suggest the assessment criteria to select a strategic energy technology R&D programs by the analytic hierarchy process, which is one of multi-criteria decision making method (MCDM)We structure 2 tiers of hierarchy for assessing a big-sized R&D program and also establish 6 criteria in the level 1, which are energy environment, economic spin-off, technical spin-off, marketability, KIER mission, and cost. We allocate the relative weights of criteria by checking the values of consistency ratio as making pairwise comparisons. The result of this research will provide the decision makers as they select a right well focused R&D program.

  • PDF

The Economic Evaluation of the Renewable Energy Projects using the Geske Model (게스케(Geske) 모델을 이용한 신재생에너지사업의 경제성 분석)

  • Jaehun Sim
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.45 no.4
    • /
    • pp.31-41
    • /
    • 2022
  • As the environmental impacts of fossil fuel energy sources increase, the South Korean government has tried to change non-environmental-friendly enery sources to environmental-friendly energy sources in order to mitigate environmental effects, which lead to global warming and air pollution. With both a limited budget and limited time, it is essential to accurately evaluate the economic and environmental effects of renewable energy projects for the efficient and effective operation of renewable energy plants. Although the traditional economic evaluation methods are not ideal for evaluating the economic impacts of renewable energy projects, they can still be used for this purpose. Renewable energy projects involve many risks due to various uncertainties. For this reason, this study utilizes a real option method, the Geske compound model, to evaluate the renewable energy projects on Jeju Island in terms of economic and environmental values. This study has developed an economic evaluation model based on the Geske compound model to investigate the influences of flexibility and uncertainty factors on the evaluation process. This study further conducts a sensitivity analysis to examine how two uncertainty factors (namely, investment cost and wind energy production) influence the economic and environmental value of renewable energy projects.

Selecting strategic energy technology R&D programs applied to the AHP approach as planning a big-sized energy R&D program (대형과제 기획시 계층분석적 의사결정기법을 적용한 전략적 에너지기술 R&D 프로그램 선정)

  • Lee, Seong-Kon;Mogi, Gento
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2007.11a
    • /
    • pp.690-693
    • /
    • 2007
  • The R&D budget of energy technology development has increased in the sector of Korean energy technology development continuously. In addition to that, KIER, the government invested research institute and unique energy technology R&D research institute, is trying to plan for a big-sized energy R&D program for the well focused R&D and excellent research outcomes. In the phase of R&D process, the planning is one of the most important sectors because it drives the direction of R&D. In this study, we suggest the assessment criteria to select a strategic energy technology R&D programs by the analytic hierarchy process, which is one of multi-criteria decision making method (MCDM). We structure 2 tiers of hierarchy for assessing a big-sized R&D program and also establish 6 criteria in the level 1, which are energy environment, economic spin-off, technical spin-off, marketability, KIER mission, and cost. We allocate the relative weights of criteria by checking the values of consistency ratio as making pairwise comparisons. The result of this research will provide the decision makers as they select a right well focused R&D program.

  • PDF