• Title/Summary/Keyword: energy model

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Neutron Cross Section Evaluation on Mo-95, Tc-99, Ru-101 and Rh-1()3 in the Fast Energy Region

  • Lee, Y. D.;J. H. Chang
    • Nuclear Engineering and Technology
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    • v.34 no.6
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    • pp.533-544
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    • 2002
  • The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

DEVELOPMENT OF A TWO-DIMENSIONAL THERMOHYDRAULIC HOT POOL MODEL AND ITS EFFECTS ON REACTIVITY FEEDBACK DURING A UTOP IN LIQUID METAL REACTORS

  • Lee, Yong-Bum;Jeong, Hae-Yong;Cho, Chung-Ho;Kwon, Young-Min;Ha, Kwi-Seok;Chang, Won-Pyo;Suk, Soo-Dong;Hahn, Do-Hee
    • Nuclear Engineering and Technology
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    • v.41 no.8
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    • pp.1053-1064
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    • 2009
  • The existence of a large sodium pool in the KALIMER, a pool-type LMR developed by the Korea Atomic Energy Research Institute, plays an important role in reactor safety and operability because it determines the grace time for operators to cope with an abnormal event and to terminate a transient before reactor enters into an accident condition. A two-dimensional hot pool model has been developed and implemented in the SSC-K code, and has been successfully applied for the assessment of safety issues in the conceptual design of KALIMER and for the analysis of anticipated system transients. The other important models of the SSC-K code include a three-dimensional core thermal-hydraulic model, a reactivity model, a passive decay heat removal system model, and an intermediate heat transport system and steam generation system model. The capability of the developed two-dimensional hot pool model was evaluated with a comparison of the temperature distribution calculated with the CFX code. The predicted hot pool coolant temperature distributions obtained with the two-dimensional hot pool model agreed well with those predicted with the CFX code. Variations in the temperature distribution of the hot pool affect the reactivity feedback due to an expansion of the control rod drive line (CRDL) immersed in the pool. The existing CRDL reactivity model of the SSC-K code has been modified based on the detailed hot pool temperature distribution obtained with the two-dimensional pool model. An analysis of an unprotected transient over power with the modified reactivity model showed an improved negative reactivity feedback effect.

Model Development of Daily and Hourly Energy Load for Department Stores (백화점 건물의 에너지 부하모델 개발)

  • 박화춘;이승수;김대진
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.12
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    • pp.1088-1094
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    • 2003
  • Case study was peformed to analyze energy load for department stores and develop energy load model to be applied to a cogeneration system. Energy loads of 14 departments were analyzed based on energy load sheets written by operators and energy load of one department store was measured through modem communication for a year. Energy load of department stores shows various variations depending on when they are opened or closed and, hours, days and months. In this paper, the measurement was compared with data in energy load sheets and resolved, and energy load model for a department store was built. It is important to use an accurate energy load model for an accurate feasibility study applying a cogeneration system to buildings.

Study on Utilizing Resources in Ecopolis -Evaluation of the Potential Heat Capacity of Sewage For Utilizing as Sewage Energy- (생태도시에서의 자원활용에 관한 연구 -하수 에너지 활용을 위한 보유열량 평가-)

  • 정용현
    • Journal of Environmental Science International
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    • v.12 no.6
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    • pp.583-591
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    • 2003
  • The research on potential energy was conducted to conserve the high-exergy energy like primary energy and utilize waste heat from sewage. From the Point of view in using the waste heat, the energy Potential of waste water from the model house was simulated. From the results, when the heated water was supplied to the model house side in order to put unused energy to Practice use, heated water had higher energy Potential than unheated water, which was due to the discharge of most of unused energy. The possessing heat capacity of sewage from heated water was increased to 40-70 percents in comparison with that from the unheated water. Therefore, it can be used as energy source for improving coefficient of performance of heat pumps. By adopting the multiple heat pump into a model house, It showed that the possessing heat capacity of sewage was reduced. It was also found that the heat was recovered as energy source fur multiple heat pump in a model house.

Theoretical Study of the Hydration of Collagen (Collagen의 수화에 대한 이론적 연구)

  • Lee Jong Myung;Jhon Mu Shik
    • Journal of the Korean Chemical Society
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    • v.22 no.6
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    • pp.403-411
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    • 1978
  • A theoretical study of the hydration of the model compound of collagen, poly(Gly-Pro-Pro), has been carried out using empirical potential energy functions. The optimum locations and binding energies of water molecules bound to the model compound have been determined by minimizing the interaction energy. The stabilization energy due to the presence of water in the first hydration shell has been evaluated by comparing the internal interaction energies between the different groups of the model compound in its non-hydrated and hydrated states. The different energy components contributing to the overall stabilization are determined and discussed.

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NEUTRON INDUCED CROSS SECTION DATA FOR IR-191 AND IR-193

  • Lee, Yong-Deok;Lee, Young-Ouk
    • Nuclear Engineering and Technology
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    • v.38 no.8
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    • pp.803-808
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    • 2006
  • The neutron induced nuclear cross section data for Ir-191 and Ir-193 were calculated and evaluated from unresolved resonance energy to 20MeV. The energy-dependent optical model potential parameters were determined based on the experimental data and applied up to 20MeV. A spherical optical model, a statistical model in an equilibrium energy region, and a multistep direct and multistep compound model in a pre-equilibrium energy region were used in the calculations. The direct capture model enhanced the fast neutron capture in the pre-equilibrium energy. The theoretically calculated cross sections were compared with the experimental data and the evaluated files. The calculations were found to be in good agreement with the experiment data. The evaluated cross section results were compiled with the ENDF-6 format. The fast energy results will be merged with the resonance parts to create a full evaluation library. The improvement of the neutron-induced cross section data will contribute to an increase in the efficiency of the production of Ir-192 as a radiation source.

Comparative Study of Implicit and Explicit Solvation Models for Probing Tryptophan Side Chain Packing in Proteins

  • Yang, Chang-Won;Pak, Young-Shang
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.828-832
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    • 2012
  • We performed replica exchange molecular dynamics (REMD) simulations of the tripzip2 peptide (betahairpin) using the GB implicit and TI3P explicit solvation models. By comparing the resulting free energy surfaces of these two solvation model, we found that the GB solvation model produced a distorted free energy map, but the explicit solvation model yielded a reasonable free energy landscape with a precise location of the native structure in its global free energy minimum state. Our result showed that in particular, the GB solvation model failed to describe the tryptophan packing of trpzip2, leading to a distorted free energy landscape. When the GB solvation model is replaced with the explicit solvation model, the distortion of free energy shape disappears with the native-like structure in the lowest free energy minimum state and the experimentally observed tryptophan packing is precisely recovered. This finding indicates that the main source of this problem is due to artifact of the GB solvation model. Therefore, further efforts to refine this model are needed for better predictions of various aromatic side chain packing forms in proteins.

Developing an Energy Consumption Model of Household Unit in Rural Area (농촌지역 농가 에너지소비 모델 개발)

  • Rhee, Shin-Ho;Wang, Jun;Yoon, Seong-Soo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.50 no.4
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    • pp.99-109
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    • 2008
  • As the price of traditional fossil fuels continue to increase, more people attach importance to the pollution of the environment caused by fossil fuel's burning, developing and using renewable energy resources has become a very important project all over the world. Also, the rural energy planning which is another method to improve energy utilization ratio and reduce environment pollution, is also regarded as a very effective way to reduce the energy consumption. There is a quantity of renewable energy resources and natural tribes in rural area, which is both feasible to develop the renewable energy and the regional energy planning. To carry out this, it is needs to know the area's quantity of renewable energy resources and the total energy consumption. This paper is to find out the relationship between rural energy consumption and rural conditions, and to found a energy consumption model which can conjecture the energy consumption in rural family. and the cost of rural family's energy consumption was founded to conjecture how much money dose it cost in rural family's energy consumption. The energy consumption model was concluded using the surveys of 76 families in 14 villages at the area of Chungcheongbuk-Do(province). The main factors to energy consumption was selected out which were number of family members, acreage of house, acreage of farmland and family's annual income.

Design of CIM(Common Information Model) Profile for Smart City Energy Monitoring (스마트시티 에너지 감시를 위한 CIM(Common Information Model) 프로파일 설계)

  • Youngil, Kim;Changhun, Chae;Yeri, Kim;Jihoon, Lee
    • KEPCO Journal on Electric Power and Energy
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    • v.8 no.2
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    • pp.127-135
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    • 2022
  • With the advent of high technologies such as the 4th Industrial Revolution and artificial intelligence and big data, efforts are being made to solve urban problems and improve the quality of life by applying new technologies in the smart city field. In addition, as carbon neutrality has emerged as an important issue due to global warming, smart city energy platform technologies such as urban energy management, efficiency improvement, and carbon reduction are in the spotlight. In order to effectively manage urban energy, energy resource information such as electricity, water, gas, hot water, heating, etc. must be collected from the management system of various energy utilities and managed on the central platform. The centrally integrated data is delivered to external city management systems that require city energy information through an energy platform. This study developed a CIM profile for smart city energy monitoring required to provide energy data to external systems. Electric data model were designed using the CIM class of IEC 61970, and water, gas, and heat data model were designed in compliance with the UML-based design ideas of IEC 61970.

An Energy Saving Method Using Cluster Group Model in Wireless Sensor Networks (무선 센서 네트워크에서 클러스터 그룹 모델을 이용한 에너지 절약 방안)

  • Kim, Jin-Su
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.12
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    • pp.4991-4996
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    • 2010
  • Clustering method in wireless sensor network is the technique that forms the cluster to aggregate the data and transmit them at the same time that they can use the energy efficiently. Even though cluster group model is based on clustering, it differs from previous method that reducing the total energy consumption by separating energy overload to cluster group head and cluster head. In this thesis, I calculate the optimal cluster group number and cluster number in this kind of cluster group model according to threshold of energy consumption model. By using that I can minimize the total energy consumption in sensor network and maximize the network lifetime. I also show that proposed cluster group model is better than previous clustering method at the point of network energy efficiency.