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Sample records for method calculations final

  1. Calculation method for the seasonal performance of heat pump compact units and validation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wemhoener, C.; Dott, R.; Afjei, Th. [University of Applied Sciences Northwestern Switzerland, Institute of Energy in Buildings, Muttenz (Switzerland); Huber, H.; Helfenfinger, D.; Keller, P.; Furter, R. [University of Applied Sciences Lucerne (HTA), Test center HLKS, Horw (Switzerland)

    2007-02-15

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at compact heat pump units that have been developed for the heating of low energy consumption houses built to MINERGIE or MINERGIE-P standards. These units, which combine the functions of space heating, domestic hot water preparation and ventilation in one unit are described. A testing procedure developed at the University of Applied Science in Lucerne, Switzerland, using a test rig for the measurement of the seasonal performance factor (SPF) is described. A calculation method based on temperature classes for the calculation of the SPF of combined heat pump systems for space heating and domestic hot water preparation that was developed by the Institute of Energy in Buildings at the University of Applied Sciences Northwestern Switzerland is examined. Two pilot plants allowing detailed field monitoring of two compact units are described. One pilot plant installed in a single-family house built to MINERGIE standard in Gelterkinden, Switzerland, provided data on a compact unit. These results of measurements made on this and a further installation in a MINERGIE-P ultra-low energy consumption house in Zeiningen, Switzerland, are presented and discussed. Calculation methods, including exergy considerations are reviewed and their validation is discussed.

  2. Innovative methods for calculation of freeway travel time using limited data : final report.

    Science.gov (United States)

    2008-01-01

    Description: Travel time estimations created by processing of simulated freeway loop detector data using proposed method have been compared with travel times reported from VISSIM model. An improved methodology was proposed to estimate freeway corrido...

  3. Final disposal room structural response calculations

    International Nuclear Information System (INIS)

    Stone, C.M.

    1997-08-01

    Finite element calculations have been performed to determine the structural response of waste-filled disposal rooms at the WIPP for a period of 10,000 years after emplacement of the waste. The calculations were performed to generate the porosity surface data for the final set of compliance calculations. The most recent reference data for the stratigraphy, waste characterization, gas generation potential, and nonlinear material response have been brought together for this final set of calculations

  4. Uneconomical top calculation method

    International Nuclear Information System (INIS)

    De Noord, M.; Vanm Sambeek, E.J.W.

    2003-08-01

    The methodology used to calculate the financial gap of renewable electricity sources and technologies is described. This methodology is used for calculating the production subsidy levels (MEP subsidies) for new renewable electricity projects in 2004 and 2005 in the Netherlands [nl

  5. Temperature and stress calculation for final disposal

    International Nuclear Information System (INIS)

    Tarandi, T.

    1979-02-01

    Temperature and stress distribution in and around the final storage facility has been calculated for three different arrangements of the tunnels: - 2 planes with 60 m vertical distance between them - 2 planes with 100 m distance and - 1 plane. The highest temperatures and stresses occur for the 2 plane alternative with distance 60 m between planes. The maximum compressive stress is in this case 24.0 MPa 140 years after the time of deposition, compared with 12.6 MPa in the 1 plane case. The maximum tensile stress exists at the surface and is in the 2 plane case 6.0 MPa 800 - 1,500 years after deposition, compared with 4.2 MPa for the 1 plane variant. An estimation of maximum tensile stresses between the tunnel planes yields a value of 1.5 MPa. The above-mentioned stresses are due to temperature distribution induced by the radioactive waste. To obtain the total stresses, initial stresses in the undisturbed rock, which vary according to location, are to be added to these stresses. (author)

  6. Methods for magnetostatic field calculation

    International Nuclear Information System (INIS)

    Vorozhtsov, S.B.

    1984-01-01

    Two methods for magnetostatic field calculation: differential and integrat are considered. Both approaches are shown to have certain merits and drawbacks, choice of the method depend on the type of the solved problem. An opportunity of combination of these tWo methods in one algorithm (hybrid method) is considered

  7. Methods for Melting Temperature Calculation

    Science.gov (United States)

    Hong, Qi-Jun

    Melting temperature calculation has important applications in the theoretical study of phase diagrams and computational materials screenings. In this thesis, we present two new methods, i.e., the improved Widom's particle insertion method and the small-cell coexistence method, which we developed in order to capture melting temperatures both accurately and quickly. We propose a scheme that drastically improves the efficiency of Widom's particle insertion method by efficiently sampling cavities while calculating the integrals providing the chemical potentials of a physical system. This idea enables us to calculate chemical potentials of liquids directly from first-principles without the help of any reference system, which is necessary in the commonly used thermodynamic integration method. As an example, we apply our scheme, combined with the density functional formalism, to the calculation of the chemical potential of liquid copper. The calculated chemical potential is further used to locate the melting temperature. The calculated results closely agree with experiments. We propose the small-cell coexistence method based on the statistical analysis of small-size coexistence MD simulations. It eliminates the risk of a metastable superheated solid in the fast-heating method, while also significantly reducing the computer cost relative to the traditional large-scale coexistence method. Using empirical potentials, we validate the method and systematically study the finite-size effect on the calculated melting points. The method converges to the exact result in the limit of a large system size. An accuracy within 100 K in melting temperature is usually achieved when the simulation contains more than 100 atoms. DFT examples of Tantalum, high-pressure Sodium, and ionic material NaCl are shown to demonstrate the accuracy and flexibility of the method in its practical applications. The method serves as a promising approach for large-scale automated material screening in which

  8. Modelling and transmission-line calculations of the final superconducting dipole and quadrupole chains of CERN's LHC collider methods and results

    CERN Document Server

    Dahlerup-Petersen, K

    2001-01-01

    Summary form only given, as follows. A long chain of superconducting magnets represents a complex load impedance for the powering and turns into a complex generator during the energy extraction. Detailed information about the circuit is needed for the calculation of a number of parameters and features, which are of vital importance for the choice of powering and extraction equipment and for the prediction of the circuit performance under normal and fault conditions. Constitution of the complex magnet chain impedance is based on a synthesized, electrical model of the basic magnetic elements. This is derived from amplitude and phase measurements of coil and ground impedances from d.c. to 50 kHz and the identification of poles and zeros of the impedance and transfer functions. An electrically compatible RLC model of each magnet type was then synthesized by means of a combination of conventional algorithms. Such models have been elaborated for the final, 15-m long LHC dipole (both apertures in series) as well as ...

  9. Friction and wear calculation methods

    CERN Document Server

    Kragelsky, I V; Kombalov, V S

    1981-01-01

    Friction and Wear: Calculation Methods provides an introduction to the main theories of a new branch of mechanics known as """"contact interaction of solids in relative motion."""" This branch is closely bound up with other sciences, especially physics and chemistry. The book analyzes the nature of friction and wear, and some theoretical relationships that link the characteristics of the processes and the properties of the contacting bodies essential for practical application of the theories in calculating friction forces and wear values. The effect of the environment on friction and wear is a

  10. Methods for calculating nonconcave entropies

    International Nuclear Information System (INIS)

    Touchette, Hugo

    2010-01-01

    Five different methods which can be used to analytically calculate entropies that are nonconcave as functions of the energy in the thermodynamic limit are discussed and compared. The five methods are based on the following ideas and techniques: (i) microcanonical contraction, (ii) metastable branches of the free energy, (iii) generalized canonical ensembles with specific illustrations involving the so-called Gaussian and Betrag ensembles, (iv) the restricted canonical ensemble, and (v) the inverse Laplace transform. A simple long-range spin model having a nonconcave entropy is used to illustrate each method

  11. Study of the embedded atom method of atomistic calculations for metals and alloys. Final report, March 1, 1986--February 29, 1992

    International Nuclear Information System (INIS)

    Johnson, R.A.

    1992-04-01

    Solids have been studied by atomistic modeling since the earliest availability of computers for scientific research. By the mid sixties, it was understood that models for metals based on reasonably short ranged two-body forces coupled with a global volume dependent contribution to the crystal energy yielded surprisingly good results for bulk calculations, but were unsatisfactory at surfaces. Little progress was made until the early eighties, when Daw and Baskes developed the Embedded-Atom Method (EAM) based on density functional theory and intended primarily for tight-packed transitional metals, and Finnis and Sinclair developed a model based on tight binding theory and intended primarily for bcc transition metals. The underlying mathematical format of both approaches is the same, and provides an extension of the earlier models through a function which in practice provides a measure of local volume dependence. The primary purpose of this research project was to investigate the implications of this mathematical format and to use the resulting insight to correlate the known physical input data with computed results of properties that are difficult to access experimentally. Embedded-Atom Method terminology is used, but this research is applicable as well to the Finnis-Sinclair model

  12. Calculational methods for lattice cells

    International Nuclear Information System (INIS)

    Askew, J.R.

    1980-01-01

    At the current stage of development, direct simulation of all the processes involved in the reactor to the degree of accuracy required is not an economic proposition, and this is achieved by progressive synthesis of models for parts of the full space/angle/energy neutron behaviour. The split between reactor and lattice calculations is one such simplification. Most reactors are constructed of repetitions of similar geometric units, the fuel elements, having broadly similar properties. Thus the provision of detailed predictions of their behaviour is an important step towards overall modelling. We shall be dealing with these lattice methods in this series of lectures, but will refer back from time to time to their relationship with overall reactor calculation The lattice cell is itself composed of somewhat similar sub-units, the fuel pins, and will itself often rely upon a further break down of modelling. Construction of a good model depends upon the identification, on physical and mathematical grounds, of the most helpful division of the calculation at this level

  13. Modeling of pollutant formation in fully premixing surface burners using a verified practice-oriented experimental reaction-kinetic calculation method. Final report

    International Nuclear Information System (INIS)

    Ruy, C.; Kremer, H.

    1996-01-01

    The intent of the present study was to simulate quantitatively pollutant formation in premixing surface burners and to describe qualitatively the share of the premixing flame in pollut emissions from atmospheric burners. For this purpose reaction-kinetic programmes for one-dimensional premixing flames were extended by a terms describing heat discharge through gas radiation. Furthermore, the calculation range for the flame was extended far into the secondary reaction zone. Temperature, CO, and NO x profiles were measured in the secondary reaction zone of premixing burners at standard pressure. The air-fuel ratio was calculated within the practically relevant range between 0.5 and 1.5, as was load behaviour. (DG) [de

  14. Direct Discrete Method for Neutronic Calculations

    International Nuclear Information System (INIS)

    Vosoughi, Naser; Akbar Salehi, Ali; Shahriari, Majid

    2002-01-01

    The objective of this paper is to introduce a new direct method for neutronic calculations. This method which is named Direct Discrete Method, is simpler than the neutron Transport equation and also more compatible with physical meaning of problems. This method is based on physic of problem and with meshing of the desired geometry, writing the balance equation for each mesh intervals and with notice to the conjunction between these mesh intervals, produce the final discrete equations series without production of neutron transport differential equation and mandatory passing from differential equation bridge. We have produced neutron discrete equations for a cylindrical shape with two boundary conditions in one group energy. The correction of the results from this method are tested with MCNP-4B code execution. (authors)

  15. Calculation methods in program CCRMN

    Energy Technology Data Exchange (ETDEWEB)

    Chonghai, Cai [Nankai Univ., Tianjin (China). Dept. of Physics; Qingbiao, Shen [Chinese Nuclear Data Center, Beijing, BJ (China)

    1996-06-01

    CCRMN is a program for calculating complex reactions of a medium-heavy nucleus with six light particles. In CCRMN, the incoming particles can be neutrons, protons, {sup 4}He, deuterons, tritons and {sup 3}He. the CCRMN code is constructed within the framework of the optical model, pre-equilibrium statistical theory based on the exciton model and the evaporation model. CCRMN is valid in 1{approx} MeV energy region, it can give correct results for optical model quantities and all kinds of reaction cross sections. This program has been applied in practical calculations and got reasonable results.

  16. Calculation of extreme wind atlases using mesoscale modeling. Final report

    DEFF Research Database (Denmark)

    Larsén, Xiaoli Guo; Badger, Jake

    This is the final report of the project PSO-10240 "Calculation of extreme wind atlases using mesoscale modeling". The overall objective is to improve the estimation of extreme winds by developing and applying new methodologies to confront the many weaknesses in the current methodologies as explai...

  17. Methods in nuclear reactors calculations

    International Nuclear Information System (INIS)

    Velarde, G.

    1966-01-01

    Studies are made of the neutron transport equation corresponding to the the real and virtual reactors, as well as the starting hypotheses. Methods are developed to solve the transport equation in slab geometry, and P l ; B l ; M l ; S n and discrete ordinates approximations. (Author)

  18. Pile Load Capacity – Calculation Methods

    Directory of Open Access Journals (Sweden)

    Wrana Bogumił

    2015-12-01

    Full Text Available The article is a review of the current problems of the foundation pile capacity calculations. The article considers the main principles of pile capacity calculations presented in Eurocode 7 and other methods with adequate explanations. Two main methods are presented: α – method used to calculate the short-term load capacity of piles in cohesive soils and β – method used to calculate the long-term load capacity of piles in both cohesive and cohesionless soils. Moreover, methods based on cone CPTu result are presented as well as the pile capacity problem based on static tests.

  19. Monte Carlo methods to calculate impact probabilities

    Science.gov (United States)

    Rickman, H.; Wiśniowski, T.; Wajer, P.; Gabryszewski, R.; Valsecchi, G. B.

    2014-09-01

    Context. Unraveling the events that took place in the solar system during the period known as the late heavy bombardment requires the interpretation of the cratered surfaces of the Moon and terrestrial planets. This, in turn, requires good estimates of the statistical impact probabilities for different source populations of projectiles, a subject that has received relatively little attention, since the works of Öpik (1951, Proc. R. Irish Acad. Sect. A, 54, 165) and Wetherill (1967, J. Geophys. Res., 72, 2429). Aims: We aim to work around the limitations of the Öpik and Wetherill formulae, which are caused by singularities due to zero denominators under special circumstances. Using modern computers, it is possible to make good estimates of impact probabilities by means of Monte Carlo simulations, and in this work, we explore the available options. Methods: We describe three basic methods to derive the average impact probability for a projectile with a given semi-major axis, eccentricity, and inclination with respect to a target planet on an elliptic orbit. One is a numerical averaging of the Wetherill formula; the next is a Monte Carlo super-sizing method using the target's Hill sphere. The third uses extensive minimum orbit intersection distance (MOID) calculations for a Monte Carlo sampling of potentially impacting orbits, along with calculations of the relevant interval for the timing of the encounter allowing collision. Numerical experiments are carried out for an intercomparison of the methods and to scrutinize their behavior near the singularities (zero relative inclination and equal perihelion distances). Results: We find an excellent agreement between all methods in the general case, while there appear large differences in the immediate vicinity of the singularities. With respect to the MOID method, which is the only one that does not involve simplifying assumptions and approximations, the Wetherill averaging impact probability departs by diverging toward

  20. Assessment of seismic margin calculation methods

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.

    1989-03-01

    Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs

  1. Broyden's method in nuclear structure calculations

    International Nuclear Information System (INIS)

    Baran, Andrzej; Bulgac, Aurel; Forbes, Michael McNeil; Hagen, Gaute; Nazarewicz, Witold; Schunck, Nicolas; Stoitsov, Mario V.

    2008-01-01

    Broyden's method, widely used in quantum chemistry electronic-structure calculations for the numerical solution of nonlinear equations in many variables, is applied in the context of the nuclear many-body problem. Examples include the unitary gas problem, the nuclear density functional theory with Skyrme functionals, and the nuclear coupled-cluster theory. The stability of the method, its ease of use, and its rapid convergence rates make Broyden's method a tool of choice for large-scale nuclear structure calculations

  2. Calculation methods for determining dose equivalent

    International Nuclear Information System (INIS)

    Endres, G.W.R.; Tanner, J.E.; Scherpelz, R.I.; Hadlock, D.E.

    1988-01-01

    A series of calculations of neutron fluence as a function of energy in an anthropomorphic phantom was performed to develop a system for determining effective dose equivalent for external radiation sources. critical organ dose equivalents are calculated and effective dose equivalents are determined using ICRP-26 methods. Quality factors based on both present definitions and ICRP-40 definitions are used in the analysis. The results of these calculations are presented and discussed

  3. Computational methods in calculating superconducting current problems

    Science.gov (United States)

    Brown, David John, II

    Various computational problems in treating superconducting currents are examined. First, field inversion in spatial Fourier transform space is reviewed to obtain both one-dimensional transport currents flowing down a long thin tape, and a localized two-dimensional current. The problems associated with spatial high-frequency noise, created by finite resolution and experimental equipment, are presented, and resolved with a smooth Gaussian cutoff in spatial frequency space. Convergence of the Green's functions for the one-dimensional transport current densities is discussed, and particular attention is devoted to the negative effects of performing discrete Fourier transforms alone on fields asymptotically dropping like 1/r. Results of imaging simulated current densities are favorably compared to the original distributions after the resulting magnetic fields undergo the imaging procedure. The behavior of high-frequency spatial noise, and the behavior of the fields with a 1/r asymptote in the imaging procedure in our simulations is analyzed, and compared to the treatment of these phenomena in the published literature. Next, we examine calculation of Mathieu and spheroidal wave functions, solutions to the wave equation in elliptical cylindrical and oblate and prolate spheroidal coordinates, respectively. These functions are also solutions to Schrodinger's equations with certain potential wells, and are useful in solving time-varying superconducting problems. The Mathieu functions are Fourier expanded, and the spheroidal functions expanded in associated Legendre polynomials to convert the defining differential equations to recursion relations. The infinite number of linear recursion equations is converted to an infinite matrix, multiplied by a vector of expansion coefficients, thus becoming an eigenvalue problem. The eigenvalue problem is solved with root solvers, and the eigenvector problem is solved using a Jacobi-type iteration method, after preconditioning the

  4. HTSL massive motor. Project: Motor field calculation. Final report

    International Nuclear Information System (INIS)

    Gutt, H.J.; Gruener, A.

    2003-01-01

    HTS motors up to 300 kW were to be developed and optimized. For this, specific calculation methods were enhanced to include superconducting rotor types (hysteresis, reluctance and permanent magnet HTS rotors). The experiments were carried out in a SHM70-45 hysteresis motor. It was shown how static and dynamic trapped field magnetisation of the rotor with YBCO rings will increase flux in the air gap motor, increasing the motor capacity to twice its original level. (orig.) [de

  5. Manual method for dose calculation in gynecologic brachytherapy

    International Nuclear Information System (INIS)

    Vianello, Elizabeth A.; Almeida, Carlos E. de; Biaggio, Maria F. de

    1998-01-01

    This paper describes a manual method for dose calculation in brachytherapy of gynecological tumors, which allows the calculation of the doses at any plane or point of clinical interest. This method uses basic principles of vectorial algebra and the simulating orthogonal films taken from the patient with the applicators and dummy sources in place. The results obtained with method were compared with the values calculated with the values calculated with the treatment planning system model Theraplan and the agreement was better than 5% in most cases. The critical points associated with the final accuracy of the proposed method is related to the quality of the image and the appropriate selection of the magnification factors. This method is strongly recommended to the radiation oncology centers where are no treatment planning systems available and the dose calculations are manually done. (author)

  6. Methods of bone marrow dose calculation

    International Nuclear Information System (INIS)

    Taboaco, R.C.

    1982-02-01

    Several methods of bone marrow dose calculation for photon irradiation were analised. After a critical analysis, the author proposes the adoption, by the Instituto de Radioprotecao e Dosimetria/CNEN, of Rosenstein's method for dose calculations in Radiodiagnostic examinations and Kramer's method in case of occupational irradiation. It was verified by Eckerman and Simpson that for monoenergetic gamma emitters uniformly distributed within the bone mineral of the skeleton the dose in the bone surface can be several times higher than dose in skeleton. In this way, is also proposed the Calculation of tissue-air ratios for bone surfaces in some irradiation geometries and photon energies to be included in the Rosenstein's method for organ dose calculation in Radiodiagnostic examinations. (Author) [pt

  7. Simplified dose calculation method for mantle technique

    International Nuclear Information System (INIS)

    Scaff, L.A.M.

    1984-01-01

    A simplified dose calculation method for mantle technique is described. In the routine treatment of lymphom as using this technique, the daily doses at the midpoints at five anatomical regions are different because the thicknesses are not equal. (Author) [pt

  8. Computerized accounting methods. Final report

    International Nuclear Information System (INIS)

    1994-01-01

    This report summarizes the results of the research performed under the Task Order on computerized accounting methods in a period from 03 August to 31 December 1994. Computerized nuclear material accounting methods are analyzed and evaluated. Selected methods are implemented in a hardware-software complex developed as a prototype of the local network-based CONMIT system. This complex has been put into trial operation for test and evaluation of the selected methods at two selected ''Kurchatov Institute'' Russian Research Center (''KI'' RRC) nuclear facilities. Trial operation is carried out since the beginning of Initial Physical Inventory Taking in these facilities that was performed in November 1994. Operation of CONMIT prototype system was demonstrated in the middle of December 1994. Results of evaluation of CONMIT prototype system features and functioning under real operating conditions are considered. Conclusions are formulated on the ways of further development of computerized nuclear material accounting methods. The most important conclusion is a need to strengthen computer and information security features supported by the operating environment. Security provisions as well as other LANL Client/Server System approaches being developed by Los Alamos National Laboratory are recommended for selection of software and hardware components to be integrated into production version of CONMIT system for KI RRC

  9. Simple Calculation Programs for Biology Immunological Methods

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Simple Calculation Programs for Biology Immunological Methods. Computation of Ab/Ag Concentration from EISA data. Graphical Method; Raghava et al., 1992, J. Immuno. Methods 153: 263. Determination of affinity of Monoclonal Antibody. Using non-competitive ...

  10. Range calculations using multigroup transport methods

    International Nuclear Information System (INIS)

    Hoffman, T.J.; Robinson, M.T.; Dodds, H.L. Jr.

    1979-01-01

    Several aspects of radiation damage effects in fusion reactor neutron and ion irradiation environments are amenable to treatment by transport theory methods. In this paper, multigroup transport techniques are developed for the calculation of particle range distributions. These techniques are illustrated by analysis of Au-196 atoms recoiling from (n,2n) reactions with gold. The results of these calculations agree very well with range calculations performed with the atomistic code MARLOWE. Although some detail of the atomistic model is lost in the multigroup transport calculations, the improved computational speed should prove useful in the solution of fusion material design problems

  11. Method-MS. Final report

    International Nuclear Information System (INIS)

    Skipperud, L.; Popic, J.M.; Roos, P.; Salminen, S.; Nygren, U.; Sigmarsson, O.; Palsson, S.E.

    2011-05-01

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new auxiliary

  12. Method-MS. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Skipperud, L.; Popic, J.M. (Norwegian Univ. of Life Science (UMB), Isotope Lab. (Norway)); Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Salminen, S. (Univ. of Helsinki (UH) (Finland)); Nygren, U. (Swedish Defence Research Agency (FOI) (Sweden)); Sigmarsson, O.; Palsson, S.E. (Univ. of Iceland/Icelandic Radiation Protection Institute (Iceland))

    2011-05-15

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new

  13. Eigenvalue translation method for mode calculations

    International Nuclear Information System (INIS)

    Gerck, E.; Cruz, C.H.B.

    1978-11-01

    A new method is described for the first few modes calculations in a interferometer that has several advantages over the ALLMAT subroutine, the Prony Method and the Fox and Li Method. In the illustrative results shown for the same cases it can be seen that the eigenvalue translation method is typically 100 fold times faster than the usual Fox and Li Method and 10 times faster than ALLMAT [pt

  14. Calculation methods for determining dose equivalent

    International Nuclear Information System (INIS)

    Endres, G.W.R.; Tanner, J.E.; Scherpelz, R.I.; Hadlock, D.E.

    1987-11-01

    A series of calculations of neutron fluence as a function of energy in an anthropomorphic phantom was performed to develop a system for determining effective dose equivalent for external radiation sources. Critical organ dose equivalents are calculated and effective dose equivalents are determined using ICRP-26 [1] methods. Quality factors based on both present definitions and ICRP-40 definitions are used in the analysis. The results of these calculations are presented and discussed. The effective dose equivalent determined using ICRP-26 methods is significantly smaller than the dose equivalent determined by traditional methods. No existing personnel dosimeter or health physics instrument can determine effective dose equivalent. At the present time, the conversion of dosimeter response to dose equivalent is based on calculations for maximal or ''cap'' values using homogeneous spherical or cylindrical phantoms. The evaluated dose equivalent is, therefore, a poor approximation of the effective dose equivalent as defined by ICRP Publication 26. 3 refs., 2 figs., 1 tab

  15. Reactor perturbation calculations by Monte Carlo methods

    International Nuclear Information System (INIS)

    Gubbins, M.E.

    1965-09-01

    Whilst Monte Carlo methods are useful for reactor calculations involving complicated geometry, it is difficult to apply them to the calculation of perturbation worths because of the large amount of computing time needed to obtain good accuracy. Various ways of overcoming these difficulties are investigated in this report, with the problem of estimating absorbing control rod worths particularly in mind. As a basis for discussion a method of carrying out multigroup reactor calculations by Monte Carlo methods is described. Two methods of estimating a perturbation worth directly, without differencing two quantities of like magnitude, are examined closely but are passed over in favour of a third method based on a correlation technique. This correlation method is described, and demonstrated by a limited range of calculations for absorbing control rods in a fast reactor. In these calculations control rod worths of between 1% and 7% in reactivity are estimated to an accuracy better than 10% (3 standard errors) in about one hour's computing time on the English Electric KDF.9 digital computer. (author)

  16. Calculation Methods for Wallenius’ Noncentral Hypergeometric Distribution

    DEFF Research Database (Denmark)

    Fog, Agner

    2008-01-01

    Two different probability distributions are both known in the literature as "the" noncentral hypergeometric distribution. Wallenius' noncentral hypergeometric distribution can be described by an urn model without replacement with bias. Fisher's noncentral hypergeometric distribution...... is the conditional distribution of independent binomial variates given their sum. No reliable calculation method for Wallenius' noncentral hypergeometric distribution has hitherto been described in the literature. Several new methods for calculating probabilities from Wallenius' noncentral hypergeometric...... distribution are derived. Range of applicability, numerical problems, and efficiency are discussed for each method. Approximations to the mean and variance are also discussed. This distribution has important applications in models of biased sampling and in models of evolutionary systems....

  17. Simple Calculation Programs for Biology Other Methods

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Simple Calculation Programs for Biology Other Methods. Hemolytic potency of drugs. Raghava et al., (1994) Biotechniques 17: 1148. FPMAP: methods for classification and identification of microorganisms 16SrRNA. graphical display of restriction and fragment map of ...

  18. Simple method for calculating island widths

    International Nuclear Information System (INIS)

    Cary, J.R.; Hanson, J.D.; Carreras, B.A.; Lynch, V.E.

    1989-01-01

    A simple method for calculating magnetic island widths has been developed. This method uses only information obtained from integrating along the closed field line at the island center. Thus, this method is computationally less intensive than the usual method of producing surfaces of section of sufficient detail to locate and resolve the island separatrix. This method has been implemented numerically and used to analyze the buss work islands of ATF. In this case the method proves to be accurate to at least within 30%. 7 refs

  19. Willow growing - Methods of calculation and profitability

    International Nuclear Information System (INIS)

    Rosenqvist, H.

    1997-01-01

    The calculation method presented here makes it possible to conduct profitability comparisons between annual and perennial crops and in addition take the planning situation into account. The method applied is a modified total step calculation. The difference between a traditional total step calculation and the modified version is the way in which payments and disbursements are taken into account over a period of several years. This is achieved by combining the present value method and the annuity method. The choice of interest rate has great bearing on the result in perennial calculations. The various components influencing the interest rate are analysed and factors relating to the establishment of the interest rate in different situations are described. The risk factor can be an important variable component of the interest rate calculation. Risk is also addressed from an approach in accordance with portfolio theory. The application of the methods sheds light on the profitability of Salix cultivation from the viewpoint of business economics, and also how different factors influence the profitability of Salix cultivation. Aspects studied are harvesting intervals, the importance of yield level, the competitiveness of Salix versus grain cultivation, the influence of income taxes on profitability etc. Methods for evaluation of activities concerning cultivation of a perennial crop are described and also involve the application of nitrogen fertilization to Salix cultivation. Studies have been performed using these methods to look into nitrogen fertilizer profitability in Salix cultivation during the first rotation period. Nitrogen fertilizer profitability has been investigated involving both production functions and cost calculations, taking the year fertilization into consideration. 72 refs., 2 figs., 52 tabs

  20. Hybrid numerical calculation method for bend waveguides

    OpenAIRE

    Garnier , Lucas; Saavedra , C.; Castro-Beltran , Rigoberto; Lucio , José Luis; Bêche , Bruno

    2017-01-01

    National audience; The knowledge of how the light will behave in a waveguide with a radius of curvature becomes more and more important because of the development of integrated photonics, which include ring micro-resonators, phasars, and other devices with a radius of curvature. This work presents a numerical calculation method to determine the eigenvalues and eigenvectors of curved waveguides. This method is a hybrid method which uses at first conform transformation of the complex plane gene...

  1. Monte Carlo methods for shield design calculations

    International Nuclear Information System (INIS)

    Grimstone, M.J.

    1974-01-01

    A suite of Monte Carlo codes is being developed for use on a routine basis in commercial reactor shield design. The methods adopted for this purpose include the modular construction of codes, simplified geometries, automatic variance reduction techniques, continuous energy treatment of cross section data, and albedo methods for streaming. Descriptions are given of the implementation of these methods and of their use in practical calculations. 26 references. (U.S.)

  2. Radiation transport calculation methods in BNCT

    International Nuclear Information System (INIS)

    Koivunoro, H.; Seppaelae, T.; Savolainen, S.

    2000-01-01

    Boron neutron capture therapy (BNCT) is used as a radiotherapy for malignant brain tumours. Radiation dose distribution is necessary to determine individually for each patient. Radiation transport and dose distribution calculations in BNCT are more complicated than in conventional radiotherapy. Total dose in BNCT consists of several different dose components. The most important dose component for tumour control is therapeutic boron dose D B . The other dose components are gamma dose D g , incident fast neutron dose D f ast n and nitrogen dose D N . Total dose is a weighted sum of the dose components. Calculation of neutron and photon flux is a complex problem and requires numerical methods, i.e. deterministic or stochastic simulation methods. Deterministic methods are based on the numerical solution of Boltzmann transport equation. Such are discrete ordinates (SN) and spherical harmonics (PN) methods. The stochastic simulation method for calculation of radiation transport is known as Monte Carlo method. In the deterministic methods the spatial geometry is partitioned into mesh elements. In SN method angular integrals of the transport equation are replaced with weighted sums over a set of discrete angular directions. Flux is calculated iteratively for all these mesh elements and for each discrete direction. Discrete ordinates transport codes used in the dosimetric calculations are ANISN, DORT and TORT. In PN method a Legendre expansion for angular flux is used instead of discrete direction fluxes, land the angular dependency comes a property of vector function space itself. Thus, only spatial iterations are required for resulting equations. A novel radiation transport code based on PN method and tree-multigrid technique (TMG) has been developed at VTT (Technical Research Centre of Finland). Monte Carlo method solves the radiation transport by randomly selecting neutrons and photons from a prespecified boundary source and following the histories of selected particles

  3. Comparative Study of Daylighting Calculation Methods

    Directory of Open Access Journals (Sweden)

    Mandala Ariani

    2018-01-01

    Full Text Available The aim of this study is to assess five daylighting calculation method commonly used in architectural study. The methods used include hand calculation methods (SNI/DPMB method and BRE Daylighting Protractors, scale models studied in an artificial sky simulator and computer programs using Dialux and Velux lighting software. The test room is conditioned by the uniform sky conditions, simple room geometry with variations of the room reflectance (black, grey, and white color. The analyses compared the result (including daylight factor, illumination, and coefficient of uniformity value and examines the similarity and contrast the result different. The color variations trial is used to analyses the internally reflection factor contribution to the result.

  4. Three-dimensional space charge calculation method

    International Nuclear Information System (INIS)

    Lysenko, W.P.; Wadlinger, E.A.

    1981-01-01

    A method is presented for calculating space-charge forces suitable for use in a particle tracing code. Poisson's equation is solved in three dimensions with boundary conditions specified on an arbitrary surface by using a weighted residual method. Using a discrete particle distribution as our source input, examples are shown of off-axis, bunched beams of noncircular crosssection in radio-frequency quadrupole (RFQ) and drift-tube linac geometries

  5. Efficient pseudospectral methods for density functional calculations

    International Nuclear Information System (INIS)

    Murphy, R. B.; Cao, Y.; Beachy, M. D.; Ringnalda, M. N.; Friesner, R. A.

    2000-01-01

    Novel improvements of the pseudospectral method for assembling the Coulomb operator are discussed. These improvements consist of a fast atom centered multipole method and a variation of the Head-Gordan J-engine analytic integral evaluation. The details of the methodology are discussed and performance evaluations presented for larger molecules within the context of DFT energy and gradient calculations. (c) 2000 American Institute of Physics

  6. Monte Carlo method for array criticality calculations

    International Nuclear Information System (INIS)

    Dickinson, D.; Whitesides, G.E.

    1976-01-01

    The Monte Carlo method for solving neutron transport problems consists of mathematically tracing paths of individual neutrons collision by collision until they are lost by absorption or leakage. The fate of the neutron after each collision is determined by the probability distribution functions that are formed from the neutron cross-section data. These distributions are sampled statistically to establish the successive steps in the neutron's path. The resulting data, accumulated from following a large number of batches, are analyzed to give estimates of k/sub eff/ and other collision-related quantities. The use of electronic computers to produce the simulated neutron histories, initiated at Los Alamos Scientific Laboratory, made the use of the Monte Carlo method practical for many applications. In analog Monte Carlo simulation, the calculation follows the physical events of neutron scattering, absorption, and leakage. To increase calculational efficiency, modifications such as the use of statistical weights are introduced. The Monte Carlo method permits the use of a three-dimensional geometry description and a detailed cross-section representation. Some of the problems in using the method are the selection of the spatial distribution for the initial batch, the preparation of the geometry description for complex units, and the calculation of error estimates for region-dependent quantities such as fluxes. The Monte Carlo method is especially appropriate for criticality safety calculations since it permits an accurate representation of interacting units of fissile material. Dissimilar units, units of complex shape, moderators between units, and reflected arrays may be calculated. Monte Carlo results must be correlated with relevant experimental data, and caution must be used to ensure that a representative set of neutron histories is produced

  7. Comparison of methods for calculating decay lifetimes

    International Nuclear Information System (INIS)

    Tobocman, W.

    1978-01-01

    A simple scattering model is used to test alternative methods for calculating decay lifetimes, or equivalently, resonance widths. We consider the scattering of s-wave particles by a square well with a square barrier. Exact values for resonance energies and resonance widths are compared with values calculated from Wigner-Weisskopf perturbation theory and from the Garside-MacDonald projection operator formalism. The Garside-MacDonald formalism gives essentially exact results while the predictions of the Wigner-Weisskopf formalism are fairly poor

  8. A numerical method for resonance integral calculations

    International Nuclear Information System (INIS)

    Tanbay, Tayfun; Ozgener, Bilge

    2013-01-01

    A numerical method has been proposed for resonance integral calculations and a cubic fit based on least squares approximation to compute the optimum Bell factor is given. The numerical method is based on the discretization of the neutron slowing down equation. The scattering integral is approximated by taking into account the location of the upper limit in energy domain. The accuracy of the method has been tested by performing computations of resonance integrals for uranium dioxide isolated rods and comparing the results with empirical values. (orig.)

  9. Sputtering calculations with the discrete ordinated method

    International Nuclear Information System (INIS)

    Hoffman, T.J.; Dodds, H.L. Jr.; Robinson, M.T.; Holmes, D.K.

    1977-01-01

    The purpose of this work is to investigate the applicability of the discrete ordinates (S/sub N/) method to light ion sputtering problems. In particular, the neutral particle discrete ordinates computer code, ANISN, was used to calculate sputtering yields. No modifications to this code were necessary to treat charged particle transport. However, a cross section processing code was written for the generation of multigroup cross sections; these cross sections include a modification to the total macroscopic cross section to account for electronic interactions and small-scattering-angle elastic interactions. The discrete ordinates approach enables calculation of the sputtering yield as functions of incident energy and angle and of many related quantities such as ion reflection coefficients, angular and energy distributions of sputtering particles, the behavior of beams penetrating thin foils, etc. The results of several sputtering problems as calculated with ANISN are presented

  10. Burnup calculations using Monte Carlo method

    International Nuclear Information System (INIS)

    Ghosh, Biplab; Degweker, S.B.

    2009-01-01

    In the recent years, interest in burnup calculations using Monte Carlo methods has gained momentum. Previous burn up codes have used multigroup transport theory based calculations followed by diffusion theory based core calculations for the neutronic portion of codes. The transport theory methods invariably make approximations with regard to treatment of the energy and angle variables involved in scattering, besides approximations related to geometry simplification. Cell homogenisation to produce diffusion, theory parameters adds to these approximations. Moreover, while diffusion theory works for most reactors, it does not produce accurate results in systems that have strong gradients, strong absorbers or large voids. Also, diffusion theory codes are geometry limited (rectangular, hexagonal, cylindrical, and spherical coordinates). Monte Carlo methods are ideal to solve very heterogeneous reactors and/or lattices/assemblies in which considerable burnable poisons are used. The key feature of this approach is that Monte Carlo methods permit essentially 'exact' modeling of all geometrical detail, without resort to ene and spatial homogenization of neutron cross sections. Monte Carlo method would also be better for in Accelerator Driven Systems (ADS) which could have strong gradients due to the external source and a sub-critical assembly. To meet the demand for an accurate burnup code, we have developed a Monte Carlo burnup calculation code system in which Monte Carlo neutron transport code is coupled with a versatile code (McBurn) for calculating the buildup and decay of nuclides in nuclear materials. McBurn is developed from scratch by the authors. In this article we will discuss our effort in developing the continuous energy Monte Carlo burn-up code, McBurn. McBurn is intended for entire reactor core as well as for unit cells and assemblies. Generally, McBurn can do burnup of any geometrical system which can be handled by the underlying Monte Carlo transport code

  11. Acceleration methods and models in Sn calculations

    International Nuclear Information System (INIS)

    Sbaffoni, M.M.; Abbate, M.J.

    1984-01-01

    In some neutron transport problems solved by the discrete ordinate method, it is relatively common to observe some particularities as, for example, negative fluxes generation, slow and insecure convergences and solution instabilities. The commonly used models for neutron flux calculation and acceleration methods included in the most used codes were analyzed, in face of their use in problems characterized by a strong upscattering effect. Some special conclusions derived from this analysis are presented as well as a new method to perform the upscattering scaling for solving the before mentioned problems in this kind of cases. This method has been included in the DOT3.5 code (two dimensional discrete ordinates radiation transport code) generating a new version of wider application. (Author) [es

  12. Further development of the structure mechanics analysis method for the calculation of the structure reliability of passive components, phase II. Final report; Weiterentwicklung der strukturmechanischen Analysemethodik zur Bestimmung der Strukturzuverlaessigkeit passiver Komponenten, Phase II. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Grebner, H.; Wang, Y.; Schmipfke, T.; Sievers, J.

    2010-06-15

    Within the framework of research project RS 1163 the computer code PROST for the quantitative assessment of the structural reliability of pipe components has been further developed. Thereby models were provided and tested for the consideration of the damage mechanism 'corrosion' to determine leak and break probabilities in cylindrical structures of ferritic and austenitic reactor steels. These models are now additionally available to the model for the consideration of the damage mechanism 'fatigue'. Furthermore, the application range of the code was extended to complex geometries in regards to loading and boundary conditions. Additional code modules were developed to be able to include the results of finite element (FE) calculations. The extended analysis method was tested, amongst others, in the context of calculations for a cracked feedwater nozzle of a steam generator under thermal-mechanical cyclic loading. The stress on cracks was calculated with the FE-method. For the determination of leak probabilities the crack growth due to fatigue was estimated taking into account the ''mixed-mode'' - loading within the J-integral vector approach. Altogether, the analyses show that with the provided flexible probabilistic analysis method quantitative determination of leak probabilities of a detected or postulated crack in a complex structure geometry under thermal-mechanical loading as function of the operating time in the range of very small probability values (<1.0 E-8) to large values (>1.0 E-2) are possible. The next development steps should comprise especially the improvement of the accuracy of the method to determine break probabilities and also the consideration of approaches on crack formation due to the damage mechanisms 'fatigue' and 'corrosion', based on evaluations of national and international operating experiences.

  13. Criticality calculation method for mixer-settlers

    International Nuclear Information System (INIS)

    Gonda, Kozo; Aoyagi, Haruki; Nakano, Ko; Kamikawa, Hiroshi.

    1980-01-01

    A new criticality calculation code MACPEX has been developed to evaluate and manage the criticality of the process in the extractor of mixer-settler type. MACPEX can perform the combined calculation with the PUREX process calculation code MIXSET, to get the neutron flux and the effective multiplication constant in the mixer-settlers. MACPEX solves one-dimensional diffusion equation by the explicit difference method and the standard source-iteration technique. The characteristics of MACPEX are as follows. 1) Group constants of 4 energy groups for the 239 Pu-H 2 O solution, water, polyethylene and SUS 28 are provided. 2) The group constants of the 239 Pu-H 2 O solution are given by the functional formulae of the plutonium concentration, which is less than 50 g/l. 3) Two boundary conditions of the vacuum condition and the reflective condition are available in this code. 4) The geometrical bucklings can be calculated for a certain energy group and/or region by using the three dimentional neutron flux profiles obtained by CITATION. 5) The buckling correction search can be carried out in order to get a desired k sub(eff). (author)

  14. Methods for Calculating Empires in Quasicrystals

    Directory of Open Access Journals (Sweden)

    Fang Fang

    2017-10-01

    Full Text Available This paper reviews the empire problem for quasiperiodic tilings and the existing methods for generating the empires of the vertex configurations in quasicrystals, while introducing a new and more efficient method based on the cut-and-project technique. Using Penrose tiling as an example, this method finds the forced tiles with the restrictions in the high dimensional lattice (the mother lattice that can be cut-and-projected into the lower dimensional quasicrystal. We compare our method to the two existing methods, namely one method that uses the algorithm of the Fibonacci chain to force the Ammann bars in order to find the forced tiles of an empire and the method that follows the work of N.G. de Bruijn on constructing a Penrose tiling as the dual to a pentagrid. This new method is not only conceptually simple and clear, but it also allows us to calculate the empires of the vertex configurations in a defected quasicrystal by reversing the configuration of the quasicrystal to its higher dimensional lattice, where we then apply the restrictions. These advantages may provide a key guiding principle for phason dynamics and an important tool for self error-correction in quasicrystal growth.

  15. Method for consequence calculations for severe accidents

    International Nuclear Information System (INIS)

    Nielsen, F.; Thykier-Nielsen, S.; Walmod-Larsen, O.

    1986-08-01

    This report was commissioned by the Swedish State Power Board, who wanted a method for calculation of radiation doses in the surroundings of nuclear power plants caused by severe accidents. The PLUCON4 code were used for the calculations. A TC-SV-accident at Ringhals 1 wer chosen as example. A transient without shutdown leads to core meltdown through the reactor vessel. The pressure peak at the moment of vessel failure opens a safety valve in the dry well. Meteorolgical data for two years from the Ringhals meteorological tower were analysed to find representative weather situations. As typical weather were chosen Pasquill D with wind speed 8 m/s, and as extreme weather were chosen Pasquill F with wind speed 4.8 m/s. (author)

  16. Applying probabilistic methods for assessments and calculations for accident prevention

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    The guidelines for the prevention of accidents require plant design-specific and radioecological calculations to be made in order to show that maximum acceptable expsoure values will not be exceeded in case of an accident. For this purpose, main parameters affecting the accident scenario have to be determined by probabilistic methods. This offers the advantage that parameters can be quantified on the basis of unambigious and realistic criteria, and final results can be defined in terms of conservativity. (DG) [de

  17. Shielding calculations for the Intense Neutron Source Facility. Final report

    International Nuclear Information System (INIS)

    Battat, M.E.; Henninger, R.J.; Macdonald, J.L.; Dudziak, D.J.

    1978-06-01

    Results of shielding calculations for the Intnse Neutron Source (INS) facility are presented. The INS facility is designed to house two sources, each of which will produce D--T neutrons with intensities in the range from 1 to 3 x 10 15 n/s on a continuous basis. Topics covered include the design of the biological shield, use of two-dimensional discrete-ordinates results to specify the source terms for a Monte Carlo skyshine calculation, air activation, and dose rates in the source cell (after shutdown) due to activation of the biological shield

  18. A keff calculation method by Monte Carlo

    International Nuclear Information System (INIS)

    Shen, H; Wang, K.

    2008-01-01

    The effective multiplication factor (k eff ) is defined as the ratio between the number of neutrons in successive generations, which definition is adopted by most Monte Carlo codes (e.g. MCNP). Also, it can be thought of as the ratio of the generation rate of neutrons by the sum of the leakage rate and the absorption rate, which should exclude the effect of the neutron reaction such as (n, 2n) and (n, 3n). This article discusses the Monte Carlo method for k eff calculation based on the second definition. A new code has been developed and the results are presented. (author)

  19. Methods for calculating radiation attenuation in shields

    Energy Technology Data Exchange (ETDEWEB)

    Butler, J; Bueneman, D; Etemad, A; Lafore, P; Moncassoli, A M; Penkuhn, H; Shindo, M; Stoces, B

    1964-10-01

    In recent years the development of high-speed digital computers of large capacity has revolutionized the field of reactor shield design. For compact special-purpose reactor shields, Monte-Carlo codes in two- and three dimensional geometries are now available for the proper treatment of both the neutron and gamma- ray problems. Furthermore, techniques are being developed for the theoretical optimization of minimum-weight shield configurations for this type of reactor system. In the design of land-based power reactors, on the other hand, there is a strong incentive to reduce the capital cost of the plant, and economic considerations are also relevant to reactors designed for merchant ship propulsion. In this context simple methods are needed which are economic in their data input and computing time requirements and which, at the same time, are sufficiently accurate for design work. In general the computing time required for Monte-Carlo calculations in complex geometry is excessive for routine design calculations and the capacity of the present codes is inadequate for the proper treatment of large reactor shield systems in three dimensions. In these circumstances a wide range of simpler techniques are currently being employed for design calculations. The methods of calculation for neutrons in reactor shields fall naturally into four categories: Multigroup diffusion theory; Multigroup diffusion with removal sources; Transport codes; and Monte Carlo methods. In spite of the numerous Monte- Carlo techniques which are available for penetration and back scattering, serious problems are still encountered in practice with the scattering of gamma rays from walls of buildings which contain critical facilities and also concrete-lined discharge shafts containing irradiated fuel elements. The considerable volume of data in the unclassified literature on the solution of problems of this type in civil defence work appears not to have been evaluated for reactor shield design. In

  20. New nonlinear methods for linear transport calculations

    International Nuclear Information System (INIS)

    Adams, M.L.

    1993-01-01

    We present a new family of methods for the numerical solution of the linear transport equation. With these methods an iteration consists of an 'S N sweep' followed by an 'S 2 -like' calculation. We show, by analysis as well as numerical results, that iterative convergence is always rapid. We show that this rapid convergence does not depend on a consistent discretization of the S 2 -like equations - they can be discretized independently from the S N equations. We show further that independent discretizations can offer significant advantages over consistent ones. In particular, we find that in a wide range of problems, an accurate discretization of the S 2 -like equation can be combined with a crude discretization of the S N equations to produce an accurate S N answer. We demonstrate this by analysis as well as numerical results. (orig.)

  1. User effects on the transient system code calculations. Final report

    International Nuclear Information System (INIS)

    Aksan, S.N.; D'Auria, F.

    1995-01-01

    Large thermal-hydraulic system codes are widely used to perform safety and licensing analyses of nuclear power plants to optimize operational procedures and the plant design itself. Evaluation of the capabilities of these codes are accomplished by comparing the code predictions with the measured experimental data obtained from various types of separate effects and integral test facilities. In recent years, some attempts have been made to establish methodologies to evaluate the accuracy and the uncertainty of the code predictions and consequently judgement on the acceptability of the codes. In none of the methodologies has the influence of the code user on the calculated results been directly addressed. In this paper, the results of the investigations on the user effects for the thermal-hydraulic transient system codes is presented and discussed on the basis of some case studies. The general findings of the investigations show that in addition to user effects, there are other reasons that affect the results of the calculations and which are hidden under user effects. Both the hidden factors and the direct user effects are discussed in detail and general recommendations and conclusions are presented to control and limit them

  2. Calculating the tearing resistance of ductile steels: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Zahoor, A.

    1989-05-01

    This work was motivated by the results of fracture mechanics analysis for the low upper shelf (A-11) reactor vessel issue. The analysis indicated a need for J-resistance curve that includes crack extensions from about 0.5 to 1.0 inch. Specimens from reactor vessel surveillance capsules will not provide the needed crack extension. Therefore, there is a need for a reliable method that can be used to extrapolate small specimen J-resistance curve for evaluation of large components. This report focuses on the development of accurate J solution, assesses the impact of approximations on the current method, and proposes a criterion for extrapolating the J-resistance curve. This report presents new J-integral solutions for the compact tension (C(T)) and three-point bend bar (SE(B)) specimens. The solutions cover a wide range of crack lengths, allowing analysis for crack lengths greater than 20 percent of the specimen width. These solutions are useful for generating accurate J-resistance curves. Solutions for both the J/sub d/ and J/sub M/ are derived. The digitized form of the J/sub d/ and J/sub M/ solutions suitable for implementing into a computer code are presented in an Appendix. 20 refs., 19 figs., 7 tabs.

  3. Computing and physical methods to calculate Pu

    International Nuclear Information System (INIS)

    Mohamed, Ashraf Elsayed Mohamed

    2013-01-01

    Main limitations due to the enhancement of the plutonium content are related to the coolant void effect as the spectrum becomes faster, the neutron flux in the thermal region tends towards zero and is concentrated in the region from 10 Ke to 1 MeV. Thus, all captures by 240 Pu and 242 Pu in the thermal and epithermal resonance disappear and the 240 Pu and 242 Pu contributions to the void effect became positive. The higher the Pu content and the poorer the Pu quality, the larger the void effect. The core control in nominal or transient conditions Pu enrichment leads to a decrease in (B eff.), the efficiency of soluble boron and control rods. Also, the Doppler effect tends to decrease when Pu replaces U, so, that in case of transients the core could diverge again if the control is not effective enough. As for the voiding effect, the plutonium degradation and the 240 Pu and 242 Pu accumulation after multiple recycling lead to spectrum hardening and to a decrease in control. One solution would be to use enriched boron in soluble boron and shutdown rods. In this paper, I discuss and show the advanced computing and physical methods to calculate Pu inside the nuclear reactors and glovebox and the different solutions to be used to overcome the difficulties that effect, on safety parameters and on reactor performance, and analysis the consequences of plutonium management on the whole fuel cycle like Raw materials savings, fraction of nuclear electric power involved in the Pu management. All through two types of scenario, one involving a low fraction of the nuclear park dedicated to plutonium management, the other involving a dilution of the plutonium in all the nuclear park. (author)

  4. Overview of multifluid-flow-calculation methods

    International Nuclear Information System (INIS)

    Stewart, H.B.

    1981-01-01

    Two categories of numerical methods which may be useful in multiphase flow research are discussed. The first category includes methods which are specifically intended for accurate computation of discontinuities, such as the method of characteristics, particle-in-cell method, flux-corrected transport, and random choice methods. Methods in this category could be applied to research on rocket exhaust plumes and interior ballistics. The second category includes methods for smooth, subsonic flows, such as fractional step methods, semi-implicit method, and methods which treat convection implicitly. The subsonic flow methods could be of interest for ice flows

  5. Method for consequence calculations for severe accidents

    International Nuclear Information System (INIS)

    Nielsen, F.; Thykier-Nielsn, S.

    1987-03-01

    This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Forsmark reactor No 3. The assumption used for the calculations were a 0.06% release of iodine and cesium corresponding to a 0.1% release through the FILTRA plant at Barsebaeck. The calculations were made by means of the PLUCON4 code. Meteorological data for two years from the Forsmark meteorological tower were analysed to find representative weather situations. As typical weather pasquill D was chosen with wind speed 5 m/s, and as extreme weather, Pasquill F with wind speed 2 m/s. 23 tabs., 36 ills., 21 refs. (author)

  6. Method for consequence calculations for servere accidents

    International Nuclear Information System (INIS)

    Nielsen, F.

    1987-01-01

    With the exception of the part about collective doses, this report was commissioned by the Swedish State Power Board. The part about collective doses was commissioned by the Swedish National Institute of Radiation Protection. The report contains a calculation of radiation doses in the sursurroundings caused by a theoretical core meltdown accident at one of the Barsebaeck reactors with filtered venting through the FILTRA plant. The calculations were made by means of the PLUCON4 code. The assumption used for the calculations were givon by the Swedish National Institute of Radiation Protection as follows: Pasquill D with wind speed 3 m/s and a mixing layer at 300 m height. Elevation of the release: 100 m with no energy release. The release starts 12 hours after shut-down and its duration is one hour. The release contains 100% of the noble gasses and 0,1% of all other isotopes in a 1800 MW t -reactor. (author)

  7. Method for consequence calculations for severe accidents

    International Nuclear Information System (INIS)

    Nielsen, F.

    1988-07-01

    This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Forsmark reactor No 3. The accident sequence chosen for the calculating was a release caused by total power failure. The calculations were made by means of the PLUCON4 code. Meteorological data for two years from the Forsmark meteorological tower were analysed to find representative weather situations. As typical weather, Pasquill D was chosen with a wind speed of 5 m/s, and as extreme weather, Pasquill F with a wind speed of 2 m/s. 23 tabs., 37 ills., 20 refs. (author)

  8. Methods for thermal reactor lattice calculations

    International Nuclear Information System (INIS)

    Schneider, A.

    1976-12-01

    The American code HAMMER and the British code WIMS, for the analysis of thermal reactor lattices, have been investigated. The primary objective of this investigation was to identify the causes for the discrepancies that exist between the calculated and the experimentally determined reactivity of clean critical experiments. Three phases have been undertaken in the research: (a) Detailed comparison between the group cross-sections used by the codes; (b) Definition of the various approximations incorporated into the codes; (c) Comparison between the values of a variety of reaction rates calculated by the two codes. It was concluded that the main cause of discrepancy between calculations and experiments is due to data inaccuracies, while approximations introduced in solving the transport equation are of smaller importance

  9. Evaluation bases for calculation methods in radioecology

    International Nuclear Information System (INIS)

    Bleck-Neuhaus, J.; Boikat, U.; Franke, B.; Hinrichsen, K.; Hoepfner, U.; Ratka, R.; Steinhilber-Schwab, B.; Teufel, D.; Urbach, M.

    1982-03-01

    The seven contributions in this book deal with the state and problems of radioecology. In particular it analyses: The propagation of radioactive materials in the atmosphere, the transfer of radioactive substances from the soil into plants, respectively from animal feed into meat, the exposure pathways for, and high-risk groups of the population, the uncertainties and the band width of the ingestion factor, as well as the treatment of questions of radioecology in practice. The calculation model is assessed and the difficulty evaluated of laying down data in the general calculation basis. (DG) [de

  10. Calculation of Multiphase Chemical Equilibrium by the Modified RAND Method

    DEFF Research Database (Denmark)

    Tsanas, Christos; Stenby, Erling Halfdan; Yan, Wei

    2017-01-01

    method. The modified RAND extends the classical RAND method from single-phase chemical reaction equilibrium of ideal systems to multiphase chemical equilibrium of nonideal systems. All components in all phases are treated in the same manner and the system Gibbs energy can be used to monitor convergence....... This is the first time that modified RAND was applied to multiphase chemical equilibrium systems. The combined algorithm was tested using nine examples covering vapor–liquid (VLE) and vapor–liquid–liquid equilibria (VLLE) of ideal and nonideal reaction systems. Successive substitution provided good initial......A robust and efficient algorithm for simultaneous chemical and phase equilibrium calculations is proposed. It combines two individual nonstoichiometric solving procedures: a nested-loop method with successive substitution for the first steps and final convergence with the second-order modified RAND...

  11. Method for consequence calculations for severe accidents

    International Nuclear Information System (INIS)

    Nielsen, F.

    1988-01-01

    This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Ringhals reactor No 3/4. The accident sequence chosen for the calcualtions was a release caused by total power failure. The calculations were made by means of the PLUCON4 code. A decontamination factor of 500 is used to account for the scrubber effect. Meteorological data for two years from the Ringhals meteorological tower were analysed to find representative weather situations. As typical weather, Pasquill D, was chosen with a wind speed of 10 m/s, and as extreme weather, Pasquill E, with a wind speed of 2 m/s. 19 refs. (author)

  12. SOLAR OPACITY CALCULATIONS USING THE SUPER-TRANSITION-ARRAY METHOD

    International Nuclear Information System (INIS)

    Krief, M.; Feigel, A.; Gazit, D.

    2016-01-01

    A new opacity model has been developed based on the Super-Transition-Array (STA) method for the calculation of monochromatic opacities of plasmas in local thermodynamic equilibrium. The atomic code, named STAR (STA-Revised), is described and used to calculate spectral opacities for a solar model implementing the recent AGSS09 composition. Calculations are carried out throughout the solar radiative zone. The relative contributions of different chemical elements and atomic processes to the total Rosseland mean opacity are analyzed in detail. Monochromatic opacities and charge-state distributions are compared with the widely used Opacity Project (OP) code, for several elements near the radiation–convection interface. STAR Rosseland opacities for the solar mixture show a very good agreement with OP and the OPAL opacity code throughout the radiation zone. Finally, an explicit STA calculation was performed of the full AGSS09 photospheric mixture, including all heavy metals. It was shown that, due to their extremely low abundance, and despite being very good photon absorbers, the heavy elements do not affect the Rosseland opacity

  13. SOLAR OPACITY CALCULATIONS USING THE SUPER-TRANSITION-ARRAY METHOD

    Energy Technology Data Exchange (ETDEWEB)

    Krief, M.; Feigel, A.; Gazit, D., E-mail: menahem.krief@mail.huji.ac.il [The Racah Institute of Physics, The Hebrew University, 91904 Jerusalem (Israel)

    2016-04-10

    A new opacity model has been developed based on the Super-Transition-Array (STA) method for the calculation of monochromatic opacities of plasmas in local thermodynamic equilibrium. The atomic code, named STAR (STA-Revised), is described and used to calculate spectral opacities for a solar model implementing the recent AGSS09 composition. Calculations are carried out throughout the solar radiative zone. The relative contributions of different chemical elements and atomic processes to the total Rosseland mean opacity are analyzed in detail. Monochromatic opacities and charge-state distributions are compared with the widely used Opacity Project (OP) code, for several elements near the radiation–convection interface. STAR Rosseland opacities for the solar mixture show a very good agreement with OP and the OPAL opacity code throughout the radiation zone. Finally, an explicit STA calculation was performed of the full AGSS09 photospheric mixture, including all heavy metals. It was shown that, due to their extremely low abundance, and despite being very good photon absorbers, the heavy elements do not affect the Rosseland opacity.

  14. Methods for calculating anisotropic transfer cross sections

    International Nuclear Information System (INIS)

    Cai, Shaohui; Zhang, Yixin.

    1985-01-01

    The Legendre moments of the group transfer cross section, which are widely used in the numerical solution of the transport calculation can be efficiently and accurately constructed from low-order (K = 1--2) successive partial range moments. This is convenient for the generation of group constants. In addition, a technique to obtain group-angle correlation transfer cross section without Legendre expansion is presented. (author)

  15. Analyzed method for calculating the distribution of electrostatic field

    International Nuclear Information System (INIS)

    Lai, W.

    1981-01-01

    An analyzed method for calculating the distribution of electrostatic field under any given axial gradient in tandem accelerators is described. This method possesses satisfactory accuracy compared with the results of numerical calculation

  16. The New Performance Calculation Method of Fouled Axial Flow Compressor

    Directory of Open Access Journals (Sweden)

    Huadong Yang

    2014-01-01

    Full Text Available Fouling is the most important performance degradation factor, so it is necessary to accurately predict the effect of fouling on engine performance. In the previous research, it is very difficult to accurately model the fouled axial flow compressor. This paper develops a new performance calculation method of fouled multistage axial flow compressor based on experiment result and operating data. For multistage compressor, the whole compressor is decomposed into two sections. The first section includes the first 50% stages which reflect the fouling level, and the second section includes the last 50% stages which are viewed as the clean stage because of less deposits. In this model, the performance of the first section is obtained by combining scaling law method and linear progression model with traditional stage stacking method; simultaneously ambient conditions and engine configurations are considered. On the other hand, the performance of the second section is calculated by averaged infinitesimal stage method which is based on Reynolds’ law of similarity. Finally, the model is successfully applied to predict the 8-stage axial flow compressor and 16-stage LM2500-30 compressor. The change of thermodynamic parameters such as pressure ratio, efficiency with the operating time, and stage number is analyzed in detail.

  17. Soil structure interaction calculations: a comparison of methods

    International Nuclear Information System (INIS)

    Wight, L.; Zaslawsky, M.

    1976-01-01

    Two approaches for calculating soil structure interaction (SSI) are compared: finite element and lumped mass. Results indicate that the calculations with the lumped mass method are generally conservative compared to those obtained by the finite element method. They also suggest that a closer agreement between the two sets of calculations is possible, depending on the use of frequency-dependent soil springs and dashpots in the lumped mass calculations. There is a total lack of suitable guidelines for implementing the lumped mass method of calculating SSI, which leads to the conclusion that the finite element method is generally superior for calculative purposes

  18. Soil structure interaction calculations: a comparison of methods

    Energy Technology Data Exchange (ETDEWEB)

    Wight, L.; Zaslawsky, M.

    1976-07-22

    Two approaches for calculating soil structure interaction (SSI) are compared: finite element and lumped mass. Results indicate that the calculations with the lumped mass method are generally conservative compared to those obtained by the finite element method. They also suggest that a closer agreement between the two sets of calculations is possible, depending on the use of frequency-dependent soil springs and dashpots in the lumped mass calculations. There is a total lack of suitable guidelines for implementing the lumped mass method of calculating SSI, which leads to the conclusion that the finite element method is generally superior for calculative purposes.

  19. The multigrid method for reactor calculations

    International Nuclear Information System (INIS)

    Douglas, S.R.

    1991-07-01

    Iterative solutions to linear systems of equations are discussed. The emphasis is on the concepts that affect convergence rates of these solution methods. The multigrid method is described, including the smoothing property, restriction, and prolongation. A simple example is used to illustrate the ideas

  20. Advanced Computational Methods for Monte Carlo Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Forrest B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-12

    This course is intended for graduate students who already have a basic understanding of Monte Carlo methods. It focuses on advanced topics that may be needed for thesis research, for developing new state-of-the-art methods, or for working with modern production Monte Carlo codes.

  1. Non-iterative method to calculate the periodical distribution of temperature in reactors with thermal regeneration

    International Nuclear Information System (INIS)

    Sanchez de Alsina, O.L.; Scaricabarozzi, R.A.

    1982-01-01

    A matrix non-iterative method to calculate the periodical distribution in reactors with thermal regeneration is presented. In case of exothermic reaction, a source term will be included. A computer code was developed to calculate the final temperature distribution in solids and in the outlet temperatures of the gases. The results obtained from ethane oxidation calculation in air, using the Dietrich kinetic data are presented. This method is more advantageous than iterative methods. (E.G.) [pt

  2. Criticality calculation by the LTSN method

    International Nuclear Information System (INIS)

    Batistela, Claudia H.F.; Vilhena, Marco T. de; Borges, Volnei

    1997-01-01

    This work evaluates criticality parameters (multiplication factor and critical thickness) by the LTS N method in unidimensional slabs homogeneous and heterogeneous considering one-group model and isotropic scattering. The idea of the LTS N method encompasses the following steps: application of the Laplace transform into a set of discrete ordinates equations, analytical solution of the algebraic linear system for the transformed angular fluxes and their reconstruction by the Heaviside expansion technique. The novel feature of the proposed method is based upon the criticality parameters determination by solving a transcendental equation. Numerical results are reported. 12 refs., 2 tabs

  3. convergent methods for calculating thermodynamic Green functions

    OpenAIRE

    Bowen, S. P.; Williams, C. D.; Mancini, J. D.

    1984-01-01

    A convergent method of approximating thermodynamic Green functions is outlined briefly. The method constructs a sequence of approximants which converges independently of the strength of the Hamiltonian's coupling constants. Two new concepts associated with the approximants are introduced: the resolving power of the approximation, and conditional creation (annihilation) operators. These ideas are illustrated on an exactly soluble model and a numerical example. A convergent expression for the s...

  4. COSTS CALCULATION OF TARGET COSTING METHOD

    Directory of Open Access Journals (Sweden)

    Sebastian UNGUREANU

    2014-06-01

    Full Text Available Cost information system plays an important role in every organization in the decision making process. An important task of management is ensuring control of the operations, processes, sectors, and not ultimately on costs. Although in achieving the objectives of an organization compete more control systems (production control, quality control, etc., the cost information system is important because monitors results of the other. Detailed analysis of costs, production cost calculation, quantification of losses, estimate the work efficiency provides a solid basis for financial control. Knowledge of the costs is a decisive factor in taking decisions and planning future activities. Managers are concerned about the costs that will appear in the future, their level underpinning the supply and production decisions as well as price policy. An important factor is the efficiency of cost information system in such a way that the information provided by it may be useful for decisions and planning of the work.

  5. Homotopy analysis method for neutron diffusion calculations

    International Nuclear Information System (INIS)

    Cavdar, S.

    2009-01-01

    The Homotopy Analysis Method (HAM), proposed in 1992 by Shi Jun Liao and has been developed since then, is based on a fundamental concept in differential geometry and topology, the homotopy. It has proved useful for problems involving algebraic, linear/non-linear, ordinary/partial differential and differential-integral equations being an analytic, recursive method that provides a series sum solution. It has the advantage of offering a certain freedom for the choice of its arguments such as the initial guess, the auxiliary linear operator and the convergence control parameter, and it allows us to effectively control the rate and region of convergence of the series solution. HAM is applied for the fixed source neutron diffusion equation in this work, which is a part of our research motivated by the question of whether methods for solving the neutron diffusion equation that yield straightforward expressions but able to provide a solution of reasonable accuracy exist such that we could avoid analytic methods that are widely used but either fail to solve the problem or provide solutions through many intricate expressions that are likely to contain mistakes or numerical methods that require powerful computational resources and advanced programming skills due to their very nature or intricate mathematical fundamentals. Fourier basis are employed for expressing the initial guess due to the structure of the problem and its boundary conditions. We present the results in comparison with other widely used methods of Adomian Decomposition and Variable Separation.

  6. Final Aperture Superposition Technique applied to fast calculation of electron output factors and depth dose curves

    International Nuclear Information System (INIS)

    Faddegon, B.A.; Villarreal-Barajas, J.E.

    2005-01-01

    The Final Aperture Superposition Technique (FAST) is described and applied to accurate, near instantaneous calculation of the relative output factor (ROF) and central axis percentage depth dose curve (PDD) for clinical electron beams used in radiotherapy. FAST is based on precalculation of dose at select points for the two extreme situations of a fully open final aperture and a final aperture with no opening (fully shielded). This technique is different than conventional superposition of dose deposition kernels: The precalculated dose is differential in position of the electron or photon at the downstream surface of the insert. The calculation for a particular aperture (x-ray jaws or MLC, insert in electron applicator) is done with superposition of the precalculated dose data, using the open field data over the open part of the aperture and the fully shielded data over the remainder. The calculation takes explicit account of all interactions in the shielded region of the aperture except the collimator effect: Particles that pass from the open part into the shielded part, or visa versa. For the clinical demonstration, FAST was compared to full Monte Carlo simulation of 10x10,2.5x2.5, and 2x8 cm 2 inserts. Dose was calculated to 0.5% precision in 0.4x0.4x0.2 cm 3 voxels, spaced at 0.2 cm depth intervals along the central axis, using detailed Monte Carlo simulation of the treatment head of a commercial linear accelerator for six different electron beams with energies of 6-21 MeV. Each simulation took several hours on a personal computer with a 1.7 Mhz processor. The calculation for the individual inserts, done with superposition, was completed in under a second on the same PC. Since simulations for the pre calculation are only performed once, higher precision and resolution can be obtained without increasing the calculation time for individual inserts. Fully shielded contributions were largest for small fields and high beam energy, at the surface, reaching a maximum

  7. Calculation of radon concentration in water by toluene extraction method

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Masaaki [Tokyo Metropolitan Isotope Research Center (Japan)

    1997-02-01

    Noguchi method and Horiuchi method have been used as the calculation method of radon concentration in water. Both methods have two problems in the original, that is, the concentration calculated is changed by the extraction temperature depend on the incorrect solubility data and the concentration calculated are smaller than the correct values, because the radon calculation equation does not true to the gas-liquid equilibrium theory. However, the two problems are solved by improving the radon equation. I presented the Noguchi-Saito equation and the constant B of Horiuchi-Saito equation. The calculating results by the improved method showed about 10% of error. (S.Y.)

  8. Transportation channels calculation method in MATLAB

    International Nuclear Information System (INIS)

    Averyanov, G.P.; Budkin, V.A.; Dmitrieva, V.V.; Osadchuk, I.O.; Bashmakov, Yu.A.

    2014-01-01

    Output devices and charged particles transport channels are necessary components of any modern particle accelerator. They differ both in sizes and in terms of focusing elements depending on particle accelerator type and its destination. A package of transport line designing codes for magnet optical channels in MATLAB environment is presented in this report. Charged particles dynamics in a focusing channel can be studied easily by means of the matrix technique. MATLAB usage is convenient because its information objects are matrixes. MATLAB allows the use the modular principle to build the software package. Program blocks are small in size and easy to use. They can be executed separately or commonly. A set of codes has a user-friendly interface. Transport channel construction consists of focusing lenses (doublets and triplets). The main of the magneto-optical channel parameters are total length and lens position and parameters of the output beam in the phase space (channel acceptance, beam emittance - beam transverse dimensions, particles divergence and image stigmaticity). Choice of the channel operation parameters is based on the conditions for satisfying mutually competing demands. And therefore the channel parameters calculation is carried out by using the search engine optimization techniques.

  9. Large-scale atomic calculations using variational methods

    Energy Technology Data Exchange (ETDEWEB)

    Joensson, Per

    1995-01-01

    Atomic properties, such as radiative lifetimes, hyperfine structures and isotope shift, have been studied both theoretically and experimentally. Computer programs which calculate these properties from multiconfiguration Hartree-Fock (MCHF) and configuration interaction (CI) wave functions have been developed and tested. To study relativistic effects, a program which calculates hyperfine structures from multiconfiguration Dirac-Fock (MCDF) wave functions has also been written. A new method of dealing with radial non-orthogonalities in transition matrix elements has been investigated. This method allows two separate orbital sets to be used for the initial and final states, respectively. It is shown that, once the usual orthogonality restrictions have been overcome, systematic MCHF calculations are able to predict oscillator strengths in light atoms with high accuracy. In connection with recent high-power laser experiments, time-dependent calculations of the atomic response to intense laser fields have been performed. Using the frozen-core approximation, where the atom is modeled as an active electron moving in the average field of the core electrons and the nucleus, the active electron has been propagated in time under the influence of the laser field. Radiative lifetimes and hyperfine structures of excited states in sodium and silver have been experimentally determined using time-resolved laser spectroscopy. By recording the fluorescence light decay following laser excitation in the vacuum ultraviolet spectral region, the radiative lifetimes and hyperfine structures of the 7p{sup 2}P states in silver have been measured. The delayed-coincidence technique has been used to make very accurate measurements of the radiative lifetimes and hyperfine structures of the lowest 2P states in sodium and silver. 77 refs, 2 figs, 14 tabs.

  10. Large-scale atomic calculations using variational methods

    International Nuclear Information System (INIS)

    Joensson, Per.

    1995-01-01

    Atomic properties, such as radiative lifetimes, hyperfine structures and isotope shift, have been studied both theoretically and experimentally. Computer programs which calculate these properties from multiconfiguration Hartree-Fock (MCHF) and configuration interaction (CI) wave functions have been developed and tested. To study relativistic effects, a program which calculates hyperfine structures from multiconfiguration Dirac-Fock (MCDF) wave functions has also been written. A new method of dealing with radial non-orthogonalities in transition matrix elements has been investigated. This method allows two separate orbital sets to be used for the initial and final states, respectively. It is shown that, once the usual orthogonality restrictions have been overcome, systematic MCHF calculations are able to predict oscillator strengths in light atoms with high accuracy. In connection with recent high-power laser experiments, time-dependent calculations of the atomic response to intense laser fields have been performed. Using the frozen-core approximation, where the atom is modeled as an active electron moving in the average field of the core electrons and the nucleus, the active electron has been propagated in time under the influence of the laser field. Radiative lifetimes and hyperfine structures of excited states in sodium and silver have been experimentally determined using time-resolved laser spectroscopy. By recording the fluorescence light decay following laser excitation in the vacuum ultraviolet spectral region, the radiative lifetimes and hyperfine structures of the 7p 2 P states in silver have been measured. The delayed-coincidence technique has been used to make very accurate measurements of the radiative lifetimes and hyperfine structures of the lowest 2P states in sodium and silver. 77 refs, 2 figs, 14 tabs

  11. ALMA. Calculations of diffusion and radiation doses in connection with final storage of radioactive wastes

    International Nuclear Information System (INIS)

    Gelin, R.; Kjellbert, N.; Stenquist, C.

    1978-09-01

    Calculations of diffusion and radiation doses in connection with final storage of low-lavel and intermediate-level radioactive wastes. The results show that the doses obtained with realistic values of parameters used in the calculations are very low. However, substantially simplified assumption have been applied in the calculations. Thus more detailed models for the description of the diffusion process have to be developed. (E.R.)

  12. Moment methods with effective nuclear Hamiltonians; calculations of radial moments

    International Nuclear Information System (INIS)

    Belehrad, R.H.

    1981-02-01

    A truncated orthogonal polynomial expansion is used to evaluate the expectation value of the radial moments of the one-body density of nuclei. The expansion contains the configuration moments, , , and 2 >, where R/sup (k)/ is the operator for the k-th power of the radial coordinate r, and H is the effective nuclear Hamiltonian which is the sum of the relative kinetic energy operator and the Bruckner G matrix. Configuration moments are calculated using trace reduction formulae where the proton and neutron orbitals are treated separately in order to find expectation values of good total isospin. The operator averages are taken over many-body shell model states in the harmonic oscillator basis where all particles are active and single-particle orbitals through six major shells are included. The radial moment expectation values are calculated for the nuclei 16 O, 40 Ca, and 58 Ni and find that is usually the largest term in the expansion giving a large model space dependence to the results. For each of the 3 nuclei, a model space is found which gives the desired rms radius and then we find that the other 5 lowest moments compare favorably with other theoretical predictions. Finally, we use a method of Gordon (5) to employ the lowest 6 radial moment expectation values in the calculation of elastic electron scattering from these nuclei. For low to moderate momentum transfer, the results compare favorably with the experimental data

  13. Nodal methods in numerical reactor calculations

    International Nuclear Information System (INIS)

    Hennart, J.P.; Valle, E. del

    2004-01-01

    The present work describes the antecedents, developments and applications started in 1972 with Prof. Hennart who was invited to be part of the staff of the Nuclear Engineering Department at the School of Physics and Mathematics of the National Polytechnic Institute. Since that time and up to 1981, several master theses based on classical finite element methods were developed with applications in point kinetics and in the steady state as well as the time dependent multigroup diffusion equations. After this period the emphasis moved to nodal finite elements in 1, 2 and 3D cartesian geometries. All the thesis were devoted to the numerical solution of the neutron multigroup diffusion and transport equations, few of them including the time dependence, most of them related with steady state diffusion equations. The main contributions were as follows: high order nodal schemes for the primal and mixed forms of the diffusion equations, block-centered finite-differences methods, post-processing, composite nodal finite elements for hexagons, and weakly and strongly discontinuous schemes for the transport equation. Some of these are now being used by several researchers involved in nuclear fuel management. (Author)

  14. Nodal methods in numerical reactor calculations

    Energy Technology Data Exchange (ETDEWEB)

    Hennart, J P [UNAM, IIMAS, A.P. 20-726, 01000 Mexico D.F. (Mexico); Valle, E del [National Polytechnic Institute, School of Physics and Mathematics, Department of Nuclear Engineering, Mexico, D.F. (Mexico)

    2004-07-01

    The present work describes the antecedents, developments and applications started in 1972 with Prof. Hennart who was invited to be part of the staff of the Nuclear Engineering Department at the School of Physics and Mathematics of the National Polytechnic Institute. Since that time and up to 1981, several master theses based on classical finite element methods were developed with applications in point kinetics and in the steady state as well as the time dependent multigroup diffusion equations. After this period the emphasis moved to nodal finite elements in 1, 2 and 3D cartesian geometries. All the thesis were devoted to the numerical solution of the neutron multigroup diffusion and transport equations, few of them including the time dependence, most of them related with steady state diffusion equations. The main contributions were as follows: high order nodal schemes for the primal and mixed forms of the diffusion equations, block-centered finite-differences methods, post-processing, composite nodal finite elements for hexagons, and weakly and strongly discontinuous schemes for the transport equation. Some of these are now being used by several researchers involved in nuclear fuel management. (Author)

  15. New efficient methods for calculating watersheds

    International Nuclear Information System (INIS)

    Fehr, E; Andrade, J S Jr; Herrmann, H J; Kadau, D; Moukarzel, C F; Da Cunha, S D; Da Silva, L R; Oliveira, E A

    2009-01-01

    We present an advanced algorithm for the determination of watershed lines on digital elevation models (DEMs) which is based on the iterative application of invasion percolation (IP). The main advantage of our method over previously proposed ones is that it has a sub-linear time-complexity. This enables us to process systems comprising up to 10 8 sites in a few CPU seconds. Using our algorithm we are able to demonstrate, convincingly and with high accuracy, the fractal character of watershed lines. We find the fractal dimension of watersheds to be D f = 1.211 ± 0.001 for artificial landscapes, D f = 1.10 ± 0.01 for the Alps and D f = 1.11 ± 0.01 for the Himalayas

  16. Quantum Monte Carlo diagonalization method as a variational calculation

    International Nuclear Information System (INIS)

    Mizusaki, Takahiro; Otsuka, Takaharu; Honma, Michio.

    1997-01-01

    A stochastic method for performing large-scale shell model calculations is presented, which utilizes the auxiliary field Monte Carlo technique and diagonalization method. This method overcomes the limitation of the conventional shell model diagonalization and can extremely widen the feasibility of shell model calculations with realistic interactions for spectroscopic study of nuclear structure. (author)

  17. Assessment of chemical exposures: calculation methods for environmental professionals

    National Research Council Canada - National Science Library

    Daugherty, Jack E

    1997-01-01

    ... on by scientists, businessmen, and policymakers. Assessment of Chemical Exposures: Calculation Methods for Environmental Professionals addresses the expanding scope of exposure assessments in both the workplace and environment...

  18. Comparison of different dose calculation methods for irregular photon fields

    International Nuclear Information System (INIS)

    Zakaria, G.A.; Schuette, W.

    2000-01-01

    In this work, 4 calculation methods (Wrede method, Clarskon method of sector integration, beam-zone method of Quast and pencil-beam method of Ahnesjoe) are introduced to calculate point doses in different irregular photon fields. The calculations cover a typical mantle field, an inverted Y-field and different blocked fields for 4 and 10 MV photon energies. The results are compared to those of measurements in a water phantom. The Clarkson and the pencil-beam method have been proved to be the methods of equal standard in relation to accuracy. Both of these methods are being distinguished by minimum deviations and applied in our clinical routine work. The Wrede and beam-zone methods deliver useful results to central beam and yet provide larger deviations in calculating points beyond the central axis. (orig.) [de

  19. Core burn-up calculation method of JRR-3

    International Nuclear Information System (INIS)

    Kato, Tomoaki; Yamashita, Kiyonobu

    2007-01-01

    SRAC code system is utilized for core burn-up calculation of JRR-3. SRAC code system includes calculation modules such as PIJ, PIJBURN, ANISN and CITATION for making effective cross section and calculation modules such as COREBN and HIST for core burn-up calculation. As for calculation method for JRR-3, PIJBURN (Cell burn-up calculation module) is used for making effective cross section of fuel region at each burn-up step. PIJ, ANISN and CITATION are used for making effective cross section of non-fuel region. COREBN and HIST is used for core burn-up calculation and fuel management. This paper presents details of NRR-3 core burn-up calculation. FNCA Participating countries are expected to carry out core burn-up calculation of domestic research reactor by SRAC code system by utilizing the information of this paper. (author)

  20. A mathematical method to calculate efficiency of BF3 detectors

    International Nuclear Information System (INIS)

    Si Fenni; Hu Qingyuan; Peng Taiping

    2009-01-01

    In order to calculate absolute efficiency of the BF 3 detector, MCNP/4C code is applied to calculate relative efficiency of the BF 3 detector first, and then absolute efficiency is figured out through mathematical techniques. Finally an energy response curve of the BF 3 detector for 1-20 MeV neutrons is derived. It turns out that efficiency of BF 3 detector are relatively uniform for 2-16 MeV neutrons. (authors)

  1. Comments on Simplified Calculation Method for Fire Exposed Concrete Columns

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    1998-01-01

    The author has developed new simplified calculation methods for fire exposed columns. Methods, which are found In ENV 1992-1-2 chapter 4.3 and in proposal for Danish code of Practise DS411 chapter 9. In the present supporting document the methods are derived and 50 eccentrically loaded fire expos...... columns are calculated and compared to results of full-scale tests. Furthermore 500 columns are calculated in order to present each test result related to a variation of the calculation in time of fire resistance....

  2. Current trends in methods for neutron diffusion calculations

    International Nuclear Information System (INIS)

    Adams, C.H.

    1977-01-01

    Current work and trends in the application of neutron diffusion theory to reactor design and analysis are reviewed. Specific topics covered include finite-difference methods, synthesis methods, nodal calculations, finite-elements and perturbation theory

  3. Evolution of calculation methods taking into account severe accidents

    International Nuclear Information System (INIS)

    L'Homme, A.; Courtaud, J.M.

    1990-12-01

    During the first decade of PWRs operation in France the calculation methods used for design and operation have improved very much. This paper gives a general analysis of the calculation methods evolution in parallel with the evolution of safety approach concerning PWRs. Then a comprehensive presentation of principal calculation tools is presented as applied during the past decade. An effort is done to predict the improvements in near future

  4. Method of characteristics - Based sensitivity calculations for international PWR benchmark

    International Nuclear Information System (INIS)

    Suslov, I. R.; Tormyshev, I. V.; Komlev, O. G.

    2013-01-01

    Method to calculate sensitivity of fractional-linear neutron flux functionals to transport equation coefficients is proposed. Implementation of the method on the basis of MOC code MCCG3D is developed. Sensitivity calculations for fission intensity for international PWR benchmark are performed. (authors)

  5. Reactor kinetics methods development. Final report

    International Nuclear Information System (INIS)

    Hansen, K.F.; Henry, A.F.

    1978-01-01

    This report is a qualitative summary of research conducted at MIT from 1967 to 1977 in the area of reactor kinetics methods. The objectives of the research were to find methods of integration of various mathematical models of nuclear reactor transients. From the beginning the work was aimed at numerical integration methods. Specific areas of research, discussed in more detail following, included: integration of multigroup diffusion theory models by finite difference and finite element methods; response matrix and nodal methods; coarse-mesh homogenization; and special treatment of boundary conditions

  6. Iterative acceleration methods for Monte Carlo and deterministic criticality calculations

    International Nuclear Information System (INIS)

    Urbatsch, T.J.

    1995-11-01

    If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors

  7. Iterative acceleration methods for Monte Carlo and deterministic criticality calculations

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, T.J.

    1995-11-01

    If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors.

  8. A New Thermodynamic Calculation Method for Binary Alloys: Part I: Statistical Calculation of Excess Functions

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The improved form of calculation formula for the activities of the components in binary liquids and solid alloys has been derived based on the free volume theory considering excess entropy and Miedema's model for calculating the formation heat of binary alloys. A calculation method of excess thermodynamic functions for binary alloys, the formulas of integral molar excess properties and partial molar excess properties for solid ordered or disordered binary alloys have been developed. The calculated results are in good agreement with the experimental values.

  9. Calculating the albedo characteristics by the method of transmission probabilities

    International Nuclear Information System (INIS)

    Lukhvich, A.A.; Rakhno, I.L.; Rubin, I.E.

    1983-01-01

    The possibility to use the method of transmission probabilities for calculating the albedo characteristics of homogeneous and heterogeneous zones is studied. The transmission probabilities method is a numerical method for solving the transport equation in the integrated form. All calculations have been conducted as a one-group approximation for the planes and rods with different optical thicknesses and capture-to-scattering ratios. Above calculations for plane and cylindrical geometries have shown the possibility to use the numerical method of transmission probabilities for calculating the albedo characteristics of homogeneous and heterogeneous zones with high accuracy. In this case the computer time consumptions are minimum even with the cylindrical geometry, if the interpolation calculation of characteristics is used for the neutrons of the first path

  10. A finite element method for SSI time history calculation

    International Nuclear Information System (INIS)

    Ni, X.; Gantenbein, F.; Petit, M.

    1989-01-01

    The method which is proposed is based on a finite element modelization for the soil and the structure and a time history calculation. It has been developed for plane and axisymmetric geometries. The principle of this method is presented, then applications are given, first to a linear calculation for which results will be compared to those obtained by standard methods. Then results for a non linear behavior are described

  11. Acceleration methods for assembly-level transport calculations

    International Nuclear Information System (INIS)

    Adams, Marvin L.; Ramone, Gilles

    1995-01-01

    A family acceleration methods for the iterations that arise in assembly-level transport calculations is presented. A single iteration in these schemes consists of a transport sweep followed by a low-order calculation which is itself a simplified transport problem. It is shown that a previously-proposed method fitting this description is unstable in two and three dimensions. It is presented a family of methods and shown that some members are unconditionally stable. (author). 8 refs, 4 figs, 4 tabs

  12. A finite element method for SSI time history calculations

    International Nuclear Information System (INIS)

    Ni, X.M.; Gantenbein, F.; Petit, M.

    1989-01-01

    The method which is proposed is based on a finite element modelisation for the soil and the structure and a time history calculation. It has been developed for plane and axisymmetric geometries. The principle of this method will be presented, then applications will be given, first to a linear calculation for which results will be compared to those obtained by standard methods. Then results for a non linear behavior will be described

  13. Method-MS, final report 2010

    DEFF Research Database (Denmark)

    Skipperud, Lindis; Popic, Jelena M.; Roos, Per

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry...

  14. Comparison of calculational methods for EBT reactor nucleonics

    International Nuclear Information System (INIS)

    Henninger, R.J.; Seed, T.J.; Soran, P.D.; Dudziak, D.J.

    1980-01-01

    Nucleonic calculations for a preliminary conceptual design of the first wall/blanket/shield/coil assembly for an EBT reactor are described. Two-dimensional Monte Carlo, and one- and two-dimensional discrete-ordinates calculations are compared. Good agreement for the calculated values of tritium breeding and nuclear heating is seen. We find that the three methods are all useful and complementary as a design of this type evolves

  15. Direct methods for seismic profiling. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bleistein, N.; Cohen, J.K.; Hagin, F.G.

    1979-12-12

    A coordinated research program in inverse problems was concluded. The program evolved from formulation to analytical solution to implemented computer algorithms. There were two main lines of research in this program: a velocity inversion method, with application to seismic exploration, and a physical optics inverse scattering method for reflector mapping, with application to nondestructive evaluation. In each case, computer algorithms based on the theoretical results were tested on real or testbed data from the area of the cited application. Research goals of both a theoretical and practical nature were achieved. 34 figures.

  16. Hybrid Monte-Carlo method for ICF calculations

    International Nuclear Information System (INIS)

    Clouet, J.F.; Samba, G.

    2003-01-01

    ) conduction and ray-tracing for laser description. Radiation transport is usually solved by a Monte-Carlo method. In coupling diffusion approximation and transport description, the difficult part comes from the need for an implicit discretization of the emission-absorption terms: this problem was solved by using the symbolic Monte-Carlo method. This means that at each step of the simulation a matrix is computed by a Monte-Carlo method which accounts for the radiation energy exchange between the cells. Because of time step limitation by hydrodynamic motion, energy exchange is limited to a small number of cells and the matrix remains sparse. This matrix is added to usual diffusion matrix for thermal and radiative conductions: finally we arrive at a non-symmetric linear system to invert. A generalized Marshak condition describe the coupling between transport and diffusion. In this paper we will present the principles of the method and numerical simulation of an ICF hohlraum. We shall illustrate the benefits of the method by comparing the results with full implicit Monte-Carlo calculations. In particular we shall show how the spectral cut-off evolves during the propagation of the radiative front in the gold wall. Several issues are still to be addressed (robust algorithm for spectral cut- off calculation, coupling with ALE capabilities): we shall briefly discuss these problems. (authors)

  17. The development and validation of control rod calculation methods

    International Nuclear Information System (INIS)

    Rowlands, J.L.; Sweet, D.W.; Franklin, B.M.

    1979-01-01

    Fission rate distributions have been measured in the zero power critical facility, ZEBRA, for a series of eight different arrays of boron carbide control rods. Diffusion theory calculations have been compared with these measurements. The normalised fission rates differ by up to about 30% in some regions, between the different arrays, and these differences are well predicted by the calculations. A development has been made to a method used to produce homogenised cross sections for lattice regions containing control rods. Calculations show that the method also reproduces the reaction rate within the rod and the fission rate dip at the surface of the rod in satisfactory agreement with the more accurate calculations which represent the fine structure of the rod. A comparison between diffusion theory and transport theory calculations of control rod reactivity worths in the CDFR shows that for the standard design method the finite mesh approximation and the difference between diffusion theory and transport theory (the transport correction) tend to cancel and result in corrections to be applied to the standard mesh diffusion theory calculations of about +- 2% or less. This result applies for mesh centred finite difference diffusion theory codes and for the arrays of natural boron carbide control rods for which the calculations were made. Improvements have also been made to the effective diffusion coefficients used in diffusion theory calculations for control rod followers and these give satisfactory agreement with transport theory calculations. (U.K.)

  18. Quantum mechanical methods for calculation of force constants

    International Nuclear Information System (INIS)

    Mullally, D.J.

    1985-01-01

    The focus of this thesis is upon the calculation of force constants; i.e., the second derivatives of the potential energy with respect to nuclear displacements. This information is useful for the calculation of molecular vibrational modes and frequencies. In addition, it may be used for the location and characterization of equilibrium and transition state geometries. The methods presented may also be applied to the calculation of electric polarizabilities and infrared and Raman vibrational intensities. Two approaches to this problem are studied and evaluated: finite difference methods and analytical techniques. The most suitable method depends on the type and level of theory used to calculate the electronic wave function. Double point displacement finite differencing is often required for accurate calculation of the force constant matrix. These calculations require energy and gradient calculations on both sides of the geometry of interest. In order to speed up these calculations, a novel method is presented that uses geometry dependent information about the wavefunction. A detailed derivation for the analytical evaluation of force constants with a complete active space multiconfiguration self consistent field wave function is presented

  19. New method for calculation of integral characteristics of thermal plumes

    DEFF Research Database (Denmark)

    Zukowska, Daria; Popiolek, Zbigniew; Melikov, Arsen Krikor

    2008-01-01

    A method for calculation of integral characteristics of thermal plumes is proposed. The method allows for determination of the integral parameters of plumes based on speed measurements performed with omnidirectional low velocity thermoanemometers. The method includes a procedure for calculation...... of the directional velocity (upward component of the mean velocity). The method is applied for determination of the characteristics of an asymmetric thermal plume generated by a sitting person. The method was validated in full-scale experiments in a climatic chamber with a thermal manikin as a simulator of a sitting...

  20. The pseudo-harmonics method applied to depletion calculation

    International Nuclear Information System (INIS)

    Silva, F.C. da; Amaral, J.A.C.; Thome, Z.D.

    1989-01-01

    In this paper, a new method for performing depletion calculations, based on the use of the Pseudo-Harmonics perturbation method, was developed. The fuel burnup was considered as a global perturbation and the multigroup difusion equations were rewriten in such a way as to treat the soluble boron concentration as the eigenvalue. By doing this, the critical boron concentration can be obtained by a perturbation method. A test of the new method was performed for a H 2 O-colled, D 2 O-moderated reactor. Comparison with direct calculation showed that this method is very accurate and efficient. (author) [pt

  1. Statistics of Monte Carlo methods used in radiation transport calculation

    International Nuclear Information System (INIS)

    Datta, D.

    2009-01-01

    Radiation transport calculation can be carried out by using either deterministic or statistical methods. Radiation transport calculation based on statistical methods is basic theme of the Monte Carlo methods. The aim of this lecture is to describe the fundamental statistics required to build the foundations of Monte Carlo technique for radiation transport calculation. Lecture note is organized in the following way. Section (1) will describe the introduction of Basic Monte Carlo and its classification towards the respective field. Section (2) will describe the random sampling methods, a key component of Monte Carlo radiation transport calculation, Section (3) will provide the statistical uncertainty of Monte Carlo estimates, Section (4) will describe in brief the importance of variance reduction techniques while sampling particles such as photon, or neutron in the process of radiation transport

  2. Comparison study on cell calculation method of fast reactor

    International Nuclear Information System (INIS)

    Chiba, Gou

    2002-10-01

    Effective cross sections obtained by cell calculations are used in core calculations in current deterministic methods. Therefore, it is important to calculate the effective cross sections accurately and several methods have been proposed. In this study, some of the methods are compared to each other using a continuous energy Monte Carlo method as a reference. The result shows that the table look-up method used in Japan Nuclear Cycle Development Institute (JNC) sometimes has a difference over 10% in effective microscopic cross sections and be inferior to the sub-group method. The problem was overcome by introducing a new nuclear constant system developed in JNC, in which the ultra free energy group library is used. The system can also deal with resonance interaction effects between nuclides which are not able to be considered by other methods. In addition, a new method was proposed to calculate effective cross section accurately for power reactor fuel subassembly where the new nuclear constant system cannot be applied. This method uses the sub-group method and the ultra fine energy group collision probability method. The microscopic effective cross sections obtained by this method agree with the reference values within 5% difference. (author)

  3. Methods for tornado frequency calculation of nuclear power plant

    International Nuclear Information System (INIS)

    Liu Haibin; Li Lin

    2012-01-01

    In order to take probabilistic safety assessment of nuclear power plant tornado attack event, a method to calculate tornado frequency of nuclear power plant is introduced based on HAD 101/10 and NUREG/CR-4839 references. This method can consider history tornado frequency of the plant area, construction dimension, intensity various along with tornado path and area distribution and so on and calculate the frequency of different scale tornado. (authors)

  4. Internal quality control of RIA with Tonks error calculation method

    International Nuclear Information System (INIS)

    Chen Xiaodong

    1996-01-01

    According to the methodology feature of RIA, an internal quality control chart with Tonks error calculation method which is suitable for RIA is designed. The quality control chart defines the value of the allowance error with normal reference range. The method has the simplicity of its performance and directly perceived through the senses. Taking the example of determining T 3 and T 4 , the calculation of allowance error, drawing of quality control chart and the analysis of result are introduced

  5. Improvement of methods for calculation of sound insulation in buildings

    OpenAIRE

    Mašović, Draško B.

    2015-01-01

    The main object of this work are the methods for calculation of sound insulation based on the classical model of sound propagation in buildings and single-number rating of sound insulation. The aim of the work is inspection of the possibilities for improvement of standard methods for quantification and calculation of sound insulation, in order to achieve higher accuracy of the obtained numerical values and their correlation with subjective impression of the acoustic comfort in buildings. Proc...

  6. Development of 3-D FBR heterogeneous core calculation method based on characteristics method

    International Nuclear Information System (INIS)

    Takeda, Toshikazu; Maruyama, Manabu; Hamada, Yuzuru; Nishi, Hiroshi; Ishibashi, Junichi; Kitano, Akihiro

    2002-01-01

    A new 3-D transport calculation method taking into account the heterogeneity of fuel assemblies has been developed by combining the characteristics method and the nodal transport method. In the axial direction the nodal transport method is applied, and the characteristics method is applied to take into account the radial heterogeneity of fuel assemblies. The numerical calculations have been performed to verify 2-D radial calculations of FBR assemblies and partial core calculations. Results are compared with the reference Monte-Carlo calculations. A good agreement has been achieved. It is shown that the present method has an advantage in calculating reaction rates in a small region

  7. 3D electric field calculation with surface charge method

    International Nuclear Information System (INIS)

    Yamada, S.

    1992-01-01

    This paper describes an outline and some examples of three dimensional electric field calculations with a computer code developed at NIRS. In the code, a surface charge method is adopted because of it's simplicity in the mesh establishing procedure. The charge density in a triangular mesh is assumed to distribute with a linear function of the position. The electric field distribution is calculated for a pair of drift tubes with the focusing fingers on the opposing surfaces. The field distribution in an acceleration gap is analyzed with a Fourier-Bessel series expansion method. The calculated results excellently reproduces the measured data with a magnetic model. (author)

  8. Validation of calculational methods for nuclear criticality safety - approved 1975

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The American National Standard for Nuclear Criticality Safety in Operations with Fissionable Materials Outside Reactors, N16.1-1975, states in 4.2.5: In the absence of directly applicable experimental measurements, the limits may be derived from calculations made by a method shown to be valid by comparison with experimental data, provided sufficient allowances are made for uncertainties in the data and in the calculations. There are many methods of calculation which vary widely in basis and form. Each has its place in the broad spectrum of problems encountered in the nuclear criticality safety field; however, the general procedure to be followed in establishing validity is common to all. The standard states the requirements for establishing the validity and area(s) of applicability of any calculational method used in assessing nuclear criticality safety

  9. Comparison of electrical conductivity calculation methods for natural waters

    Science.gov (United States)

    McCleskey, R. Blaine; Nordstrom, D. Kirk; Ryan, Joseph N.

    2012-01-01

    The capability of eleven methods to calculate the electrical conductivity of a wide range of natural waters from their chemical composition was investigated. A brief summary of each method is presented including equations to calculate the conductivities of individual ions, the ions incorporated, and the method's limitations. The ability of each method to reliably predict the conductivity depends on the ions included, effective accounting of ion pairing, and the accuracy of the equation used to estimate the ionic conductivities. The performances of the methods were evaluated by calculating the conductivity of 33 environmentally important electrolyte solutions, 41 U.S. Geological Survey standard reference water samples, and 1593 natural water samples. The natural waters tested include acid mine waters, geothermal waters, seawater, dilute mountain waters, and river water impacted by municipal waste water. The three most recent conductivity methods predict the conductivity of natural waters better than other methods. Two of the recent methods can be used to reliably calculate the conductivity for samples with pH values greater than about 3 and temperatures between 0 and 40°C. One method is applicable to a variety of natural water types with a range of pH from 1 to 10, temperature from 0 to 95°C, and ionic strength up to 1 m.

  10. Calculation method for gamma dose rates from Gaussian puffs

    Energy Technology Data Exchange (ETDEWEB)

    Thykier-Nielsen, S; Deme, S; Lang, E

    1995-06-01

    The Lagrangian puff models are widely used for calculation of the dispersion of releases to the atmosphere. Basic output from such models is concentration of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on the semi-infinite cloud model. This method is however only applicable for puffs with large dispersion parameters, i.e. for receptors far away from the release point. The exact calculation of the cloud dose using volume integral requires large computer time usually exceeding what is available for real time calculations. The volume integral for gamma doses could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor because only a few of the relevant parameters are considered. A multi-parameter method for calculation of gamma doses is described here. This method uses precalculated values of the gamma dose rates as a function of E{sub {gamma}}, {sigma}{sub y}, the asymmetry factor - {sigma}{sub y}/{sigma}{sub z}, the height of puff center - H and the distance from puff center R{sub xy}. To accelerate the calculations the release energy, for each significant radionuclide in each energy group, has been calculated and tabulated. Based on the precalculated values and suitable interpolation procedure the calculation of gamma doses needs only short computing time and it is almost independent of the number of radionuclides considered. (au) 2 tabs., 15 ills., 12 refs.

  11. Calculation method for gamma dose rates from Gaussian puffs

    International Nuclear Information System (INIS)

    Thykier-Nielsen, S.; Deme, S.; Lang, E.

    1995-06-01

    The Lagrangian puff models are widely used for calculation of the dispersion of releases to the atmosphere. Basic output from such models is concentration of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on the semi-infinite cloud model. This method is however only applicable for puffs with large dispersion parameters, i.e. for receptors far away from the release point. The exact calculation of the cloud dose using volume integral requires large computer time usually exceeding what is available for real time calculations. The volume integral for gamma doses could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor because only a few of the relevant parameters are considered. A multi-parameter method for calculation of gamma doses is described here. This method uses precalculated values of the gamma dose rates as a function of E γ , σ y , the asymmetry factor - σ y /σ z , the height of puff center - H and the distance from puff center R xy . To accelerate the calculations the release energy, for each significant radionuclide in each energy group, has been calculated and tabulated. Based on the precalculated values and suitable interpolation procedure the calculation of gamma doses needs only short computing time and it is almost independent of the number of radionuclides considered. (au) 2 tabs., 15 ills., 12 refs

  12. Classical Methods and Calculation Algorithms for Determining Lime Requirements

    Directory of Open Access Journals (Sweden)

    André Guarçoni

    Full Text Available ABSTRACT The methods developed for determination of lime requirements (LR are based on widely accepted principles. However, the formulas used for calculation have evolved little over recent decades, and in some cases there are indications of their inadequacy. The aim of this study was to compare the lime requirements calculated by three classic formulas and three algorithms, defining those most appropriate for supplying Ca and Mg to coffee plants and the smaller possibility of causing overliming. The database used contained 600 soil samples, which were collected in coffee plantings. The LR was estimated by the methods of base saturation, neutralization of Al3+, and elevation of Ca2+ and Mg2+ contents (two formulas and by the three calculation algorithms. Averages of the lime requirements were compared, determining the frequency distribution of the 600 lime requirements (LR estimated through each calculation method. In soils with low cation exchange capacity at pH 7, the base saturation method may fail to adequately supply the plants with Ca and Mg in many situations, while the method of Al3+ neutralization and elevation of Ca2+ and Mg2+ contents can result in the calculation of application rates that will increase the pH above the suitable range. Among the methods studied for calculating lime requirements, the algorithm that predicts reaching a defined base saturation, with adequate Ca and Mg supply and the maximum application rate limited to the H+Al value, proved to be the most efficient calculation method, and it can be recommended for use in numerous crops conditions.

  13. Calculation method for gamma-dose rates from spherical puffs

    International Nuclear Information System (INIS)

    Thykier-Nielsen, S.; Deme, S.; Lang, E.

    1993-05-01

    The Lagrangian puff-models are widely used for calculation of the dispersion of atmospheric releases. Basic output from such models are concentrations of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on semi-infinite cloud model. This method is however only applicable for points far away from the release point. The exact calculation of the cloud dose using the volume integral requires significant computer time. The volume integral for the gamma dose could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor due to the fact that the same correction factors are used for all isotopes. The authors describe a more elaborate correction method. This method uses precalculated values of the gamma-dose rate as a function of the puff dispersion parameter (δ p ) and the distance from the puff centre for four energy groups. The release of energy for each radionuclide in each energy group has been calculated and tabulated. Based on these tables and a suitable interpolation procedure the calculation of gamma doses takes very short time and is almost independent of the number of radionuclides. (au) (7 tabs., 7 ills., 12 refs.)

  14. Hybrid SN Laplace Transform Method For Slab Lattice Calculations

    International Nuclear Information System (INIS)

    Segatto, Cynthia F.; Vilhena, Marco T.; Zani, Jose H.; Barros, Ricardo C.

    2008-01-01

    In typical lattice cells where a highly absorbing, small fuel element is embedded in the moderator, a large weakly absorbing medium, high-order transport methods become unnecessary. In this paper we describe a hybrid discrete ordinates (S N ) method for slab lattice calculations. This hybrid S N method combines the convenience of a low-order S N method in the moderator with a high-order S N method in the fuel. We use special fuel-moderator interface conditions based on an approximate angular flux interpolation analytical method and the Laplace transform (LTS N ) numerical method to calculate the neutron flux distribution and the thermal disadvantage factor. We present numerical results for a range of typical model problems. (authors)

  15. Application of nonparametric statistic method for DNBR limit calculation

    International Nuclear Information System (INIS)

    Dong Bo; Kuang Bo; Zhu Xuenong

    2013-01-01

    Background: Nonparametric statistical method is a kind of statistical inference method not depending on a certain distribution; it calculates the tolerance limits under certain probability level and confidence through sampling methods. The DNBR margin is one important parameter of NPP design, which presents the safety level of NPP. Purpose and Methods: This paper uses nonparametric statistical method basing on Wilks formula and VIPER-01 subchannel analysis code to calculate the DNBR design limits (DL) of 300 MW NPP (Nuclear Power Plant) during the complete loss of flow accident, simultaneously compared with the DL of DNBR through means of ITDP to get certain DNBR margin. Results: The results indicate that this method can gain 2.96% DNBR margin more than that obtained by ITDP methodology. Conclusions: Because of the reduction of the conservation during analysis process, the nonparametric statistical method can provide greater DNBR margin and the increase of DNBR margin is benefited for the upgrading of core refuel scheme. (authors)

  16. Use of the Local Variation Methods for Nuclear Design Calculations

    International Nuclear Information System (INIS)

    Zhukov, A.I.

    2006-01-01

    A new problem-solving method for steady-state equations, which describe neutron diffusion, is presented. The method bases on a variation principal for steady-state diffusion equations and direct search the minimum of a corresponding functional. Benchmark problem calculation for power of fuel assemblies show ∼ 2% relative accuracy

  17. Optimization method for quantitative calculation of clay minerals in soil

    Indian Academy of Sciences (India)

    However, no reliable method for quantitative analysis of clay minerals has been established so far. In this study, an attempt was made to propose an optimization method for the quantitative ... 2. Basic principles. The mineralogical constitution of soil is rather complex. ... K2O, MgO, and TFe as variables for the calculation.

  18. Efficient Calculation of Near Fields in the FDTD Method

    DEFF Research Database (Denmark)

    Franek, Ondrej

    2011-01-01

    When calculating frequency-domain near fields by the FDTD method, almost 50 % reduction in memory and CPU operations can be achieved if only E-fields are stored during the main time-stepping loop and H-fields computed later. An improved method of obtaining the H-fields from Faraday's Law is prese...

  19. Linear augmented plane wave method for self-consistent calculations

    International Nuclear Information System (INIS)

    Takeda, T.; Kuebler, J.

    1979-01-01

    O.K. Andersen has recently introduced a linear augmented plane wave method (LAPW) for the calculation of electronic structure that was shown to be computationally fast. A more general formulation of an LAPW method is presented here. It makes use of a freely disposable number of eigenfunctions of the radial Schroedinger equation. These eigenfunctions can be selected in a self-consistent way. The present formulation also results in a computationally fast method. It is shown that Andersen's LAPW is obtained in a special limit from the present formulation. Self-consistent test calculations for copper show the present method to be remarkably accurate. As an application, scalar-relativistic self-consistent calculations are presented for the band structure of FCC lanthanum. (author)

  20. Comparison between ASHRAE and ISO thermal transmittance calculation methods

    DEFF Research Database (Denmark)

    Blanusa, Petar; Goss, William P.; Roth, Hartwig

    2007-01-01

    is proportional to the glazing/frame sightline distance that is also proportional to the total glazing spacer length. An example calculation of the overall heat transfer and thermal transmittance (U-value or U-factor) using the two methods for a thermally broken, aluminum framed slider window is presented....... The fenestration thermal transmittance calculations analyses presented in this paper show that small differences exist between the calculated thermal transmittance values produced by the ISO and ASHRAE methods. The results also show that the overall thermal transmittance difference between the two methodologies...... decreases as the total window area (glazing plus frame) increases. Thus, the resulting difference in thermal transmittance values for the two methods is negligible for larger windows. This paper also shows algebraically that the differences between the ISO and ASHRAE methods turn out to be due to the way...

  1. Introduction to quantum calculation methods in high resolution NMR

    International Nuclear Information System (INIS)

    Goldman, M.

    1996-01-01

    New techniques as for instance the polarization transfer, the coherence with several quanta and the double Fourier transformation have appeared fifteen years ago. These techniques constitute a considerable advance in NMR. Indeed, they allow to study more complex molecules than it was before possible. But with these advances, the classical description of the NMR is not enough to understand precisely the physical phenomena induced by these methods. It is then necessary to resort to quantum calculation methods. The aim of this work is to present these calculation methods. After some recalls of quantum mechanics, the author describes the NMR with the density matrix, reviews the main methods of double Fourier transformation and then gives the principle of the relaxation times calculation. (O.M.)

  2. Pressure algorithm for elliptic flow calculations with the PDF method

    Science.gov (United States)

    Anand, M. S.; Pope, S. B.; Mongia, H. C.

    1991-01-01

    An algorithm to determine the mean pressure field for elliptic flow calculations with the probability density function (PDF) method is developed and applied. The PDF method is a most promising approach for the computation of turbulent reacting flows. Previous computations of elliptic flows with the method were in conjunction with conventional finite volume based calculations that provided the mean pressure field. The algorithm developed and described here permits the mean pressure field to be determined within the PDF calculations. The PDF method incorporating the pressure algorithm is applied to the flow past a backward-facing step. The results are in good agreement with data for the reattachment length, mean velocities, and turbulence quantities including triple correlations.

  3. Comparison of calculational methods for liquid metal reactor shields

    International Nuclear Information System (INIS)

    Carter, L.L.; Moore, F.S.; Morford, R.J.; Mann, F.M.

    1985-09-01

    A one-dimensional comparison is made between Monte Carlo (MCNP), discrete ordinances (ANISN), and diffusion theory (MlDX) calculations of neutron flux and radiation damage from the core of the Fast Flux Test Facility (FFTF) out to the reactor vessel. Diffusion theory was found to be reasonably accurate for the calculation of both total flux and radiation damage. However, for large distances from the core, the calculated flux at very high energies is low by an order of magnitude or more when the diffusion theory is used. Particular emphasis was placed in this study on the generation of multitable cross sections for use in discrete ordinates codes that are self-shielded, consistent with the self-shielding employed in the generation of cross sections for use with diffusion theory. The Monte Carlo calculation, with a pointwise representation of the cross sections, was used as the benchmark for determining the limitations of the other two calculational methods. 12 refs., 33 figs

  4. Temperature Calculation of Annular Fuel Pellet by Finite Difference Method

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yong Sik; Bang, Je Geon; Kim, Dae Ho; Kim, Sun Ki; Lim, Ik Sung; Song, Kun Woo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-10-15

    KAERI has started an innovative fuel development project for applying dual-cooled annular fuel to existing PWR reactor. In fuel design, fuel temperature is the most important factor which can affect nuclear fuel integrity and safety. Many models and methodologies, which can calculate temperature distribution in a fuel pellet have been proposed. However, due to the geometrical characteristics and cooling condition differences between existing solid type fuel and dual-cooled annular fuel, current fuel temperature calculation models can not be applied directly. Therefore, the new heat conduction model of fuel pellet was established. In general, fuel pellet temperature is calculated by FDM(Finite Difference Method) or FEM(Finite Element Method), because, temperature dependency of fuel thermal conductivity and spatial dependency heat generation in the pellet due to the self-shielding should be considered. In our study, FDM is adopted due to high exactness and short calculation time.

  5. On the resolvents methods in quantum perturbation calculations

    International Nuclear Information System (INIS)

    Burzynski, A.

    1979-01-01

    This paper gives a systematic review of resolvent methods in quantum perturbation calculations. The case of discrete spectrum of hamiltonian is considered specially (in the literature this is the fewest considered case). The topics of calculations of quantum transitions by using of the resolvent formalism, quantum transitions between states from particular subspaces, the shifts of energy levels, are shown. The main ideas of stationary perturbation theory developed by Lippmann and Schwinger are considered too. (author)

  6. The analytic method for calculating the control rod worth

    International Nuclear Information System (INIS)

    Kim, Han Gon; Lee, Byeong Ho; Chang, Soon Heung

    1989-01-01

    We calculated the control rod worth in this paper. To avoid complexity, we did not consider burnable poisons and soluble boron. The system was localized within one assembly. The control rod was treated as not an absorber but an another boundary. Thus all of the group constants were unchanged before and after control rod insertion. And we discussed the method for calculation of the reactivity of the whole core

  7. The method of calculation of pipelines laid on supports

    OpenAIRE

    Benin D.M.

    2017-01-01

    this article focuses on the issue of laying pipelines on supports and the method of calculation of vertical and horizontal loads acting on the support. As pipelines can be water piping systems, heat networks, oil and mazout lines, condensate lines, steam lines, etc. this article describes the calculations of supports for pipelines laid above ground, in crowded channels, premises, on racks, in impassable channels, hanging supports, etc. The paper explores recommendations for placement of the s...

  8. Method for dose calculation in intracavitary irradiation of endometrical carcinoma

    International Nuclear Information System (INIS)

    Zevrieva, I.F.; Ivashchenko, N.T.; Musapirova, N.A.; Fel'dman, S.Z.; Sajbekov, T.S.

    1979-01-01

    A method for dose calculation for the conditions of intracavitary gamma therapy of endometrial carcinoma using spherical and linear 60 Co sources was elaborated. Calculations of dose rates for different amount and orientation of spherical radiation sources and for different planes were made with the aid of BEhSM-4M computer. Dosimet were made with the aid of BEhSM-4M computer. Dosimetric study of dose fields was made using a phantom imitating the real conditions of irradiation. Discrepancies between experimental and calculated values are within the limits of the experiment accuracy

  9. Nuclear data and multigroup methods in fast reactor calculations

    International Nuclear Information System (INIS)

    Gur, Y.

    1975-03-01

    The work deals with fast reactor multigroup calculations, and the efficient treatment of basic nuclear data, which serves as raw material for the calculations. Its purpose is twofold: to build a computer code system that handles a large, detailed library of basic neutron cross section data, (such as ENDF/B-III) and yields a compact set of multigroup cross sections for reactor calculations; to use the code system for comparative analysis of different libraries, in order to discover basic uncertainties that still exist in the measurement of neutron cross sections, and to determine their influence upon uncertainties in nuclear calculations. A program named NANICK which was written in two versions is presented. The first handles the American basic data library, ENDF/B-III, while the second handles the German basic data library, KEDAK. The mathematical algorithm is identical in both versions, and only the file management is different. This program calculates infinitely diluted multigroup cross sections and scattering matrices. It is complemented by the program NASIF that calculates shielding factors from resonance parameters. Different versions of NASIF were written to handle ENDF/B-III or KEDAK. New methods for evaluating in reactor calculations the long term behavior of the neutron flux as well as its fine structure are described and an efficient calculation of the shielding factors from resonance parameters is offered. (B.G.)

  10. Effectiveness of the current method of calculating member states' contributions

    CERN Document Server

    2002-01-01

    At its Two-hundred and eighty-sixth Meeting of 19 September 2001, the Finance Committee requested the Management to re-assess the effectiveness of the current method of forecasting Net National Income (NNI) for the purposes of calculating the Member States' contributions by comparing the results of the current weighted average method with a method based on a simple arithmetic average. The Finance Committee is invited to take note of this information.

  11. METHOD OF CALCULATING THE OPTIMAL HEAT EMISSION GEOTHERMAL WELLS

    Directory of Open Access Journals (Sweden)

    A. I. Akaev

    2015-01-01

    Full Text Available This paper presents a simplified method of calculating the optimal regimes of the fountain and the pumping exploitation of geothermal wells, reducing scaling and corrosion during operation. Comparative characteristics to quantify the heat of formation for these methods of operation under the same pressure at the wellhead. The problem is solved graphic-analytical method based on a balance of pressure in the well with the heat pump. 

  12. Polarizable Embedded RI-CC2 Method for Two-Photon Absorption Calculations

    DEFF Research Database (Denmark)

    Hršak, Dalibor; Khah, Alireza Marefat; Christiansen, Ove

    2015-01-01

    We present a novel polarizable embedded resolution-of-identity coupled cluster singles and approximate doubles (PERI-CC2) method for calculation of two-photon absorption (TPA) spectra of large molecular systems. The method was benchmarked for three types of systems: a water-solvated molecule...... of formamide, a uracil molecule in aqueous solution, and a set of mutants of the channelrhodopsin (ChR) protein. The first test case shows that the PERI-CC2 method is in excellent agreement with the PE-CC2 method and in good agreement with the PE-CCSD method. The uracil test case indicates that the effects...... of hydrogen bonding on the TPA of a chromophore with the nearest environment is well-described with the PERI-CC2 method. Finally, the ChR calculation shows that the PERI-CC2 method is well-suited and efficient for calculations on proteins with medium-sized chromophores....

  13. Efficient methods for time-absorption (α) eigenvalue calculations

    International Nuclear Information System (INIS)

    Hill, T.R.

    1983-01-01

    The time-absorption eigenvalue (α) calculation is one of the options found in most discrete-ordinates transport codes. Several methods have been developed at Los Alamos to improve the efficiency of this calculation. Two procedures, based on coarse-mesh rebalance, to accelerate the α eigenvalue search are derived. A hybrid scheme to automatically choose the more-effective rebalance method is described. The α rebalance scheme permits some simple modifications to the iteration strategy that eliminates many unnecessary calculations required in the standard search procedure. For several fast supercritical test problems, these methods resulted in convergence with one-fifth the number of iterations required for the conventional eigenvalue search procedure

  14. Correlation expansion: a powerful alternative multiple scattering calculation method

    International Nuclear Information System (INIS)

    Zhao Haifeng; Wu Ziyu; Sebilleau, Didier

    2008-01-01

    We introduce a powerful alternative expansion method to perform multiple scattering calculations. In contrast to standard MS series expansion, where the scattering contributions are grouped in terms of scattering order and may diverge in the low energy region, this expansion, called correlation expansion, partitions the scattering process into contributions from different small atom groups and converges at all energies. It converges faster than MS series expansion when the latter is convergent. Furthermore, it takes less memory than the full MS method so it can be used in the near edge region without any divergence problem, even for large clusters. The correlation expansion framework we derive here is very general and can serve to calculate all the elements of the scattering path operator matrix. Photoelectron diffraction calculations in a cluster containing 23 atoms are presented to test the method and compare it to full MS and standard MS series expansion

  15. Development and application of advanced methods for electronic structure calculations

    DEFF Research Database (Denmark)

    Schmidt, Per Simmendefeldt

    . For this reason, part of this thesis relates to developing and applying a new method for constructing so-called norm-conserving PAW setups, that are applicable to GW calculations by using a genetic algorithm. The effect of applying the new setups significantly affects the absolute band positions, both for bulk......This thesis relates to improvements and applications of beyond-DFT methods for electronic structure calculations that are applied in computational material science. The improvements are of both technical and principal character. The well-known GW approximation is optimized for accurate calculations...... of electronic excitations in two-dimensional materials by exploiting exact limits of the screened Coulomb potential. This approach reduces the computational time by an order of magnitude, enabling large scale applications. The GW method is further improved by including so-called vertex corrections. This turns...

  16. RCS Leak Rate Calculation with High Order Least Squares Method

    International Nuclear Information System (INIS)

    Lee, Jeong Hun; Kang, Young Kyu; Kim, Yang Ki

    2010-01-01

    As a part of action items for Application of Leak before Break(LBB), RCS Leak Rate Calculation Program is upgraded in Kori unit 3 and 4. For real time monitoring of operators, periodic calculation is needed and corresponding noise reduction scheme is used. This kind of study was issued in Korea, so there have upgraded and used real time RCS Leak Rate Calculation Program in UCN unit 3 and 4 and YGN unit 1 and 2. For reduction of the noise in signals, Linear Regression Method was used in those programs. Linear Regression Method is powerful method for noise reduction. But the system is not static with some alternative flow paths and this makes mixed trend patterns of input signal values. In this condition, the trend of signal and average of Linear Regression are not entirely same pattern. In this study, high order Least squares Method is used to follow the trend of signal and the order of calculation is rearranged. The result of calculation makes reasonable trend and the procedure is physically consistence

  17. Numerical methods for calculating thermal residual stresses and hydrogen diffusion

    International Nuclear Information System (INIS)

    Leblond, J.B.; Devaux, J.; Dubois, D.

    1983-01-01

    Thermal residual stresses and hydrogen concentrations are two major factors intervening in cracking phenomena. These parameters were numerically calculated by a computer programme (TITUS) using the FEM, during the deposition of a stainless clad on a low-alloy plate. The calculation was performed with a 2-dimensional option in four successive steps: thermal transient calculation, metallurgical transient calculation (determination of the metallurgical phase proportions), elastic-plastic transient (plain strain conditions), hydrogen diffusion transient. Temperature and phase dependence of hydrogen diffusion coefficient and solubility constant. The following results were obtained: thermal calculations are very consistent with experiments at higher temperatures (due to the introduction of fusion and solidification latent heats); the consistency is not as good (by 70 degrees) for lower temperatures (below 650 degrees C); this was attributed to the non-introduction of gamma-alpha transformation latent heat. The metallurgical phase calculation indicates that the heat affected zone is almost entirely transformed into bainite after cooling down (the martensite proportion does not exceed 5%). The elastic-plastic calculations indicate that the stresses in the heat affected zone are compressive or slightly tensile; on the other hand, higher tensile stresses develop on the boundary of the heat affected zone. The transformation plasticity has a definite influence on the final stress level. The return of hydrogen to the clad during the bainitic transformation is but an incomplete phenomenon and the hydrogen concentration in the heat affected zone after cooling down to room temperature is therefore sufficient to cause cold cracking (if no heat treatment is applied). Heat treatments are efficient in lowering the hydrogen concentration. These results enable us to draw preliminary conclusions on practical means to avoid cracking. (orig.)

  18. Cluster monte carlo method for nuclear criticality safety calculation

    International Nuclear Information System (INIS)

    Pei Lucheng

    1984-01-01

    One of the most important applications of the Monte Carlo method is the calculation of the nuclear criticality safety. The fair source game problem was presented at almost the same time as the Monte Carlo method was applied to calculating the nuclear criticality safety. The source iteration cost may be reduced as much as possible or no need for any source iteration. This kind of problems all belongs to the fair source game prolems, among which, the optimal source game is without any source iteration. Although the single neutron Monte Carlo method solved the problem without the source iteration, there is still quite an apparent shortcoming in it, that is, it solves the problem without the source iteration only in the asymptotic sense. In this work, a new Monte Carlo method called the cluster Monte Carlo method is given to solve the problem further

  19. Fast calculation method for computer-generated cylindrical holograms.

    Science.gov (United States)

    Yamaguchi, Takeshi; Fujii, Tomohiko; Yoshikawa, Hiroshi

    2008-07-01

    Since a general flat hologram has a limited viewable area, we usually cannot see the other side of a reconstructed object. There are some holograms that can solve this problem. A cylindrical hologram is well known to be viewable in 360 deg. Most cylindrical holograms are optical holograms, but there are few reports of computer-generated cylindrical holograms. The lack of computer-generated cylindrical holograms is because the spatial resolution of output devices is not great enough; therefore, we have to make a large hologram or use a small object to fulfill the sampling theorem. In addition, in calculating the large fringe, the calculation amount increases in proportion to the hologram size. Therefore, we propose what we believe to be a new calculation method for fast calculation. Then, we print these fringes with our prototype fringe printer. As a result, we obtain a good reconstructed image from a computer-generated cylindrical hologram.

  20. Numerically induced pressure excursions in two-phase-flow calculations. Final report

    International Nuclear Information System (INIS)

    Mahaffy, J.H.; Liles, D.R.

    1983-01-01

    Pressure spikes that cannot be traced to any physical origin sometimes are observed when standard Eulerian finite-difference methods are used to calculate two-phase-flow transients. This problem occurs with varying frequency in nuclear reactor safety codes such as RELAP, RETRAN, COBRA, and TRAC. These spikes usually result from numerical water packing or from interactions between spatial discretization and heat transfer

  1. Calculation of neutron importance function in fissionable assemblies using Monte Carlo method

    International Nuclear Information System (INIS)

    Feghhi, S.A.H.; Shahriari, M.; Afarideh, H.

    2007-01-01

    The purpose of the present work is to develop an efficient solution method for the calculation of neutron importance function in fissionable assemblies for all criticality conditions, based on Monte Carlo calculations. The neutron importance function has an important role in perturbation theory and reactor dynamic calculations. Usually this function can be determined by calculating the adjoint flux while solving the adjoint weighted transport equation based on deterministic methods. However, in complex geometries these calculations are very complicated. In this article, considering the capabilities of MCNP code in solving problems with complex geometries and its closeness to physical concepts, a comprehensive method based on the physical concept of neutron importance has been introduced for calculating the neutron importance function in sub-critical, critical and super-critical conditions. For this propose a computer program has been developed. The results of the method have been benchmarked with ANISN code calculations in 1 and 2 group modes for simple geometries. The correctness of these results has been confirmed for all three criticality conditions. Finally, the efficiency of the method for complex geometries has been shown by the calculation of neutron importance in Miniature Neutron Source Reactor (MNSR) research reactor

  2. Statistic method of research reactors maximum permissible power calculation

    International Nuclear Information System (INIS)

    Grosheva, N.A.; Kirsanov, G.A.; Konoplev, K.A.; Chmshkyan, D.V.

    1998-01-01

    The technique for calculating maximum permissible power of a research reactor at which the probability of the thermal-process accident does not exceed the specified value, is presented. The statistical method is used for the calculations. It is regarded that the determining function related to the reactor safety is the known function of the reactor power and many statistically independent values which list includes the reactor process parameters, geometrical characteristics of the reactor core and fuel elements, as well as random factors connected with the reactor specific features. Heat flux density or temperature is taken as a limiting factor. The program realization of the method discussed is briefly described. The results of calculating the PIK reactor margin coefficients for different probabilities of the thermal-process accident are considered as an example. It is shown that the probability of an accident with fuel element melting in hot zone is lower than 10 -8 1 per year for the reactor rated power [ru

  3. A New Method to Calculate Internal Rate of Return

    Directory of Open Access Journals (Sweden)

    azadeh zandi

    2015-09-01

    Full Text Available A number of methods have been developed to choose the best capital investment projects such as net present value, internal rate of return and etc. Internal rate of return method is probably the most popular method among managers and investors. But despite the popularity there are serious drawbacks and limitations in this method. After decades of efforts made by economists and experts to improve the method and its shortcomings, Magni in 2010 has revealed a new approach that can solves the most of internal rate of return method problems. This paper present a new method which is originated from Magni’s approach but has much more simple calculations and can resolve all the drawbacks of internal rate of return method.

  4. Comparative Study of the Volumetric Methods Calculation Using GNSS Measurements

    Science.gov (United States)

    Şmuleac, Adrian; Nemeş, Iacob; Alina Creţan, Ioana; Sorina Nemeş, Nicoleta; Şmuleac, Laura

    2017-10-01

    This paper aims to achieve volumetric calculations for different mineral aggregates using different methods of analysis and also comparison of results. To achieve these comparative studies and presentation were chosen two software licensed, namely TopoLT 11.2 and Surfer 13. TopoLT program is a program dedicated to the development of topographic and cadastral plans. 3D terrain model, level courves and calculation of cut and fill volumes, including georeferencing of images. The program Surfer 13 is produced by Golden Software, in 1983 and is active mainly used in various fields such as agriculture, construction, geophysical, geotechnical engineering, GIS, water resources and others. It is also able to achieve GRID terrain model, to achieve the density maps using the method of isolines, volumetric calculations, 3D maps. Also, it can read different file types, including SHP, DXF and XLSX. In these paper it is presented a comparison in terms of achieving volumetric calculations using TopoLT program by two methods: a method where we choose a 3D model both for surface as well as below the top surface and a 3D model in which we choose a 3D terrain model for the bottom surface and another 3D model for the top surface. The comparison of the two variants will be made with data obtained from the realization of volumetric calculations with the program Surfer 13 generating GRID terrain model. The topographical measurements were performed with equipment from Leica GPS 1200 Series. Measurements were made using Romanian position determination system - ROMPOS which ensures accurate positioning of reference and coordinates ETRS through the National Network of GNSS Permanent Stations. GPS data processing was performed with the program Leica Geo Combined Office. For the volumetric calculating the GPS used point are in 1970 stereographic projection system and for the altitude the reference is 1975 the Black Sea projection system.

  5. Emergy Algebra: Improving Matrix Methods for Calculating Tranformities

    Science.gov (United States)

    Transformity is one of the core concepts in Energy Systems Theory and it is fundamental to the calculation of emergy. Accurate evaluation of transformities and other emergy per unit values is essential for the broad acceptance, application and further development of emergy method...

  6. Advances in computational methods for Quantum Field Theory calculations

    NARCIS (Netherlands)

    Ruijl, B.J.G.

    2017-01-01

    In this work we describe three methods to improve the performance of Quantum Field Theory calculations. First, we simplify large expressions to speed up numerical integrations. Second, we design Forcer, a program for the reduction of four-loop massless propagator integrals. Third, we extend the R*

  7. Perturbation method for calculating impurity binding energy in an ...

    Indian Academy of Sciences (India)

    Nilanjan Sil

    2017-12-18

    Dec 18, 2017 ... Abstract. In the present paper, we have studied the binding energy of the shallow donor hydrogenic impurity, which is confined in an inhomogeneous cylindrical quantum dot (CQD) of GaAs-AlxGa1−xAs. Perturbation method is used to calculate the binding energy within the framework of effective mass ...

  8. Methods for calculating population dose from atmospheric dispersion of radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B L; Jow, H N; Lee, I S [Pittsburgh Univ., PA (USA)

    1978-06-01

    Curves are computed from which population dose (man-rem) due to dispersal of radioactivity from a point source can be calculated in the gaussian plume model by simple multiplication, and methods of using them and their limitations are considered. Illustrative examples are presented.

  9. Calculating Resonance Positions and Widths Using the Siegert Approximation Method

    Science.gov (United States)

    Rapedius, Kevin

    2011-01-01

    Here, we present complex resonance states (or Siegert states) that describe the tunnelling decay of a trapped quantum particle from an intuitive point of view that naturally leads to the easily applicable Siegert approximation method. This can be used for analytical and numerical calculations of complex resonances of both the linear and nonlinear…

  10. A quick method to calculate QTL confidence interval

    Indian Academy of Sciences (India)

    2011-08-19

    Aug 19, 2011 ... experimental design and analysis to reveal the real molecular nature of the ... strap sample form the bootstrap distribution of QTL location. The 2.5 and ..... ative probability to harbour a true QTL, hence x-LOD rule is not stable ... Darvasi A. and Soller M. 1997 A simple method to calculate resolv- ing power ...

  11. Simple Calculation Programs for Biology Methods in Molecular ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Simple Calculation Programs for Biology Methods in Molecular Biology. GMAP: A program for mapping potential restriction sites. RE sites in ambiguous and non-ambiguous DNA sequence; Minimum number of silent mutations required for introducing a RE sites; Set ...

  12. LEGO-Method--New Strategy for Chemistry Calculation

    Science.gov (United States)

    Molnar, Jozsef; Molnar-Hamvas, Livia

    2011-01-01

    The presented strategy of chemistry calculation is based on mole-concept, but it uses only one fundamental relationship of the amounts of substance as a basic panel. The name of LEGO-method comes from the famous toy of LEGO[R] because solving equations by grouping formulas is similar to that. The relations of mole and the molar amounts, as small…

  13. Further Stable methods for the calculation of partition functions

    International Nuclear Information System (INIS)

    Wilson, B G; Gilleron, F; Pain, J

    2007-01-01

    The extension to recursion over holes of the Gilleron and Pain method for calculating partition functions of a canonical ensemble of non-interacting bound electrons is presented as well as a generalization for the efficient computation of collisional line broadening

  14. Thick-Restart Lanczos Method for Electronic Structure Calculations

    International Nuclear Information System (INIS)

    Simon, Horst D.; Wang, L.-W.; Wu, Kesheng

    1999-01-01

    This paper describes two recent innovations related to the classic Lanczos method for eigenvalue problems, namely the thick-restart technique and dynamic restarting schemes. Combining these two new techniques we are able to implement an efficient eigenvalue problem solver. This paper will demonstrate its effectiveness on one particular class of problems for which this method is well suited: linear eigenvalue problems generated from non-self-consistent electronic structure calculations

  15. Calculation of neutron and gamma transport at the FOA:type of problems and calculation methods

    International Nuclear Information System (INIS)

    Lefvert, T.

    1975-11-01

    Protection against the effects of nuclear warfare involves the analysis of the forms of results of a nuclear charge explosion producing neutron and gamma radiation. It brings out problems leading to the calculation of criticality, leakage, and deep transmission. Methods have been developed for various kinds of particle transport problems. Applications to radiation therapy, storage of fissile materials, and fast reactors are discussed. A list (with brief description) of all neutron and gamma transport programmes of the FOA is given. (J.S.)

  16. Integrated Power Flow and Short Circuit Calculation Method for Distribution Network with Inverter Based Distributed Generation

    Directory of Open Access Journals (Sweden)

    Shan Yang

    2016-01-01

    Full Text Available Power flow calculation and short circuit calculation are the basis of theoretical research for distribution network with inverter based distributed generation. The similarity of equivalent model for inverter based distributed generation during normal and fault conditions of distribution network and the differences between power flow and short circuit calculation are analyzed in this paper. Then an integrated power flow and short circuit calculation method for distribution network with inverter based distributed generation is proposed. The proposed method let the inverter based distributed generation be equivalent to Iθ bus, which makes it suitable to calculate the power flow of distribution network with a current limited inverter based distributed generation. And the low voltage ride through capability of inverter based distributed generation can be considered as well in this paper. Finally, some tests of power flow and short circuit current calculation are performed on a 33-bus distribution network. The calculated results from the proposed method in this paper are contrasted with those by the traditional method and the simulation method, whose results have verified the effectiveness of the integrated method suggested in this paper.

  17. Cluster-cell calculation using the method of generalized homogenization

    International Nuclear Information System (INIS)

    Laletin, N.I.; Boyarinov, V.F.

    1988-01-01

    The generalized-homogenization method (GHM), used for solving the neutron transfer equation, was applied to calculating the neutron distribution in the cluster cell with a series of cylindrical cells with cylindrically coaxial zones. Single-group calculations of the technological channel of the cell of an RBMK reactor were performed using GHM. The technological channel was understood to be the reactor channel, comprised of the zirconium rod, the water or steam-water mixture, the uranium dioxide fuel element, and the zirconium tube, together with the adjacent graphite layer. Calculations were performed for channels with no internal sources and with unit incoming current at the external boundary as well as for channels with internal sources and zero current at the external boundary. The PRAKTINETs program was used to calculate the symmetric neutron distributions in the microcell and in channels with homogenized annular zones. The ORAR-TsM program was used to calculate the antisymmetric distribution in the microcell. The accuracy of the calculations were compared for the two channel versions

  18. Some experience of shielding calculations by combinatorial method

    International Nuclear Information System (INIS)

    Korobejnikov, V.V.; Oussanov, V.I.

    1996-01-01

    Some aspects of the compound systems shielding calculations by a combinatorial approach are discussed. The effectiveness of such an approach is based on the fundamental characteristic of a compound system: if some element of the system have in itself mathematical or physical properties favorable for calculation, these properties may be used in a combinatorial approach and are lost when the system is being calculated in the whole by a direct approach. The combinatorial technique applied is well known. A compound system are being splitting for two or more auxiliary subsystems (so that calculation each of them is a more simple problem than calculation of the original problem (or at last is a soluble problem if original one is not). Calculation of every subsystem are carried out by suitable method and code, the coupling being made through boundary conditions or boundary source. The special consideration in the paper is given to a fast reactor shielding combinatorial analysis and to the testing of the results received. (author)

  19. A simple method for calculation of Glauber's amplitude

    International Nuclear Information System (INIS)

    Omboo, Z.

    1983-01-01

    A method of calculating the terms of Glauber series expansions for elastic scattering of composed systems are presented. The inclusion of general scattering diagram simplifies essentially the calculation procedure. In this case the complicated combinatorical problem of reduction of similar terms in Glauber series is solved easily and determinant corresponding to various terms of the series decreases at least by a factor of two, if numbers of constituents of scattered systems are equal. If these numbers are not equal, the determinant order is equal to the smallest one

  20. Three-dimensional space-charge calculation method

    International Nuclear Information System (INIS)

    Lysenko, W.P.; Wadlinger, E.A.

    1980-09-01

    A method is presented for calculating space-charge forces on individual particles in a particle tracing simulation code. Poisson's equation is solved in three dimensions with boundary conditions specified on an arbitrary surface. When the boundary condition is defined by an impressed radio-frequency field, the external electric fields as well as the space-charge fields are determined. A least squares fitting procedure is used to calculate the coefficients of expansion functions, which need not be orthogonal nor individually satisfy the boundary condition

  1. A new method for the automatic calculation of prosody

    International Nuclear Information System (INIS)

    GUIDINI, Annie

    1981-01-01

    An algorithm is presented for the calculation of the prosodic parameters for speech synthesis. It uses the melodic patterns, composed of rising and falling slopes, suggested by G. CAELEN, and rests on: 1. An analysis into units of meaning to determine a melodic pattern 2. the calculation of the numeric values for the prosodic variations of each syllable; 3. The use of a table of vocalic values for the three parameters for each vowel according to the consonantal environment and of a table of standard duration for consonants. This method was applied in the 'SARA' program of synthesis with satisfactory results. (author) [fr

  2. Comparison of matrix exponential methods for fuel burnup calculations

    International Nuclear Information System (INIS)

    Oh, Hyung Suk; Yang, Won Sik

    1999-01-01

    Series expansion methods to compute the exponential of a matrix have been compared by applying them to fuel depletion calculations. Specifically, Taylor, Pade, Chebyshev, and rational Chebyshev approximations have been investigated by approximating the exponentials of bum matrices by truncated series of each method with the scaling and squaring algorithm. The accuracy and efficiency of these methods have been tested by performing various numerical tests using one thermal reactor and two fast reactor depletion problems. The results indicate that all the four series methods are accurate enough to be used for fuel depletion calculations although the rational Chebyshev approximation is relatively less accurate. They also show that the rational approximations are more efficient than the polynomial approximations. Considering the computational accuracy and efficiency, the Pade approximation appears to be better than the other methods. Its accuracy is better than the rational Chebyshev approximation, while being comparable to the polynomial approximations. On the other hand, its efficiency is better than the polynomial approximations and is similar to the rational Chebyshev approximation. In particular, for fast reactor depletion calculations, it is faster than the polynomial approximations by a factor of ∼ 1.7. (author). 11 refs., 4 figs., 2 tabs

  3. Comparison between calculation methods of dose rates in gynecologic brachytherapy

    International Nuclear Information System (INIS)

    Vianello, E.A.; Biaggio, M.F.; D R, M.F.; Almeida, C.E. de

    1998-01-01

    In treatments with radiations for gynecologic tumors is necessary to evaluate the quality of the results obtained by different calculation methods for the dose rates on the points of clinical interest (A, rectal, vesicle). The present work compares the results obtained by two methods. The Manual Calibration Method (MCM) tri dimensional (Vianello E., et.al. 1998), using orthogonal radiographs for each patient in treatment, and the Theraplan/T P-11 planning system (Thratonics International Limited 1990) this last one verified experimentally (Vianello et.al. 1996). The results show that MCM can be used in the physical-clinical practice with a percentile difference comparable at the computerized programs. (Author)

  4. Neutron flux calculation by means of Monte Carlo methods

    International Nuclear Information System (INIS)

    Barz, H.U.; Eichhorn, M.

    1988-01-01

    In this report a survey of modern neutron flux calculation procedures by means of Monte Carlo methods is given. Due to the progress in the development of variance reduction techniques and the improvements of computational techniques this method is of increasing importance. The basic ideas in application of Monte Carlo methods are briefly outlined. In more detail various possibilities of non-analog games and estimation procedures are presented, problems in the field of optimizing the variance reduction techniques are discussed. In the last part some important international Monte Carlo codes and own codes of the authors are listed and special applications are described. (author)

  5. The method of calculation of pipelines laid on supports

    Directory of Open Access Journals (Sweden)

    Benin D.M.

    2017-08-01

    Full Text Available this article focuses on the issue of laying pipelines on supports and the method of calculation of vertical and horizontal loads acting on the support. As pipelines can be water piping systems, heat networks, oil and mazout lines, condensate lines, steam lines, etc. this article describes the calculations of supports for pipelines laid above ground, in crowded channels, premises, on racks, in impassable channels, hanging supports, etc. The paper explores recommendations for placement of the supports on the route of the pipelines, calculation of loads on rotating and stationary supports of pipelines; inspection of stresses in the metal pipe, resulting from elongation of the piping from the temperature from the thermal expansion of the metal during operation.

  6. Use of results from microscopic methods in optical model calculations

    International Nuclear Information System (INIS)

    Lagrange, C.

    1985-11-01

    A concept of vectorization for coupled-channel programs based upon conventional methods is first presented. This has been implanted in our program for its use on the CRAY-1 computer. In a second part we investigate the capabilities of a semi-microscopic optical model involving fewer adjustable parameters than phenomenological ones. The two main ingredients of our calculations are, for spherical or well-deformed nuclei, the microscopic optical-model calculations of Jeukenne, Lejeune and Mahaux and nuclear densities from Hartree-Fock-Bogoliubov calculations using the density-dependent force D1. For transitional nuclei deformation-dependent nuclear structure wave functions are employed to weigh the scattering potentials for different shapes and channels [fr

  7. Applying Activity Based Costing (ABC) Method to Calculate Cost Price in Hospital and Remedy Services.

    Science.gov (United States)

    Rajabi, A; Dabiri, A

    2012-01-01

    Activity Based Costing (ABC) is one of the new methods began appearing as a costing methodology in the 1990's. It calculates cost price by determining the usage of resources. In this study, ABC method was used for calculating cost price of remedial services in hospitals. To apply ABC method, Shahid Faghihi Hospital was selected. First, hospital units were divided into three main departments: administrative, diagnostic, and hospitalized. Second, activity centers were defined by the activity analysis method. Third, costs of administrative activity centers were allocated into diagnostic and operational departments based on the cost driver. Finally, with regard to the usage of cost objectives from services of activity centers, the cost price of medical services was calculated. The cost price from ABC method significantly differs from tariff method. In addition, high amount of indirect costs in the hospital indicates that capacities of resources are not used properly. Cost price of remedial services with tariff method is not properly calculated when compared with ABC method. ABC calculates cost price by applying suitable mechanisms but tariff method is based on the fixed price. In addition, ABC represents useful information about the amount and combination of cost price services.

  8. Process control and optimization with simple interval calculation method

    DEFF Research Database (Denmark)

    Pomerantsev, A.; Rodionova, O.; Høskuldsson, Agnar

    2006-01-01

    for the quality improvement in the course of production. The latter is an active quality optimization, which takes into account the actual history of the process. The advocate approach is allied to the conventional method of multivariate statistical process control (MSPC) as it also employs the historical process......Methods of process control and optimization are presented and illustrated with a real world example. The optimization methods are based on the PLS block modeling as well as on the simple interval calculation methods of interval prediction and object status classification. It is proposed to employ...... the series of expanding PLS/SIC models in order to support the on-line process improvements. This method helps to predict the effect of planned actions on the product quality and thus enables passive quality control. We have also considered an optimization approach that proposes the correcting actions...

  9. A comparison of published methods of calculation of defect significance

    International Nuclear Information System (INIS)

    Ingham, T.; Harrison, R.P.

    1982-01-01

    This paper presents some of the results obtained in a round-robin calculational exercise organised by the OECD Committee on the Safety of Nuclear Installations (CSNI). The exercise was initiated to examine practical aspects of using documented elastic-plastic fracture mechanics methods to calculate defect significance. The extent to which the objectives of the exercise were met is illustrated using solutions to 'standard' problems produced by UKAEA and CEGB using the methods given in ASME XI, Appendix A, BSI PD6493, and the CEGB R/H/R6 Document. Differences in critical or tolerable defect size defined using these procedures are examined in terms of their different treatments and reasons for discrepancies are discussed. (author)

  10. Simple method to calculate percolation, Ising and Potts clusters

    International Nuclear Information System (INIS)

    Tsallis, C.

    1981-01-01

    A procedure ('break-collapse method') is introduced which considerably simplifies the calculation of two - or multirooted clusters like those commonly appearing in real space renormalization group (RG) treatments of bond-percolation, and pure and random Ising and Potts problems. The method is illustrated through two applications for the q-state Potts ferromagnet. The first of them concerns a RG calculation of the critical exponent ν for the isotropic square lattice: numerical consistence is obtained (particularly for q→0) with den Nijs conjecture. The second application is a compact reformulation of the standard star-triangle and duality transformations which provide the exact critical temperature for the anisotropic triangular and honeycomb lattices. (Author) [pt

  11. Thermal disadvantage factor calculation by the multiregion collision probability method

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2004-01-01

    A multi-region collision probability formulation that is capable of applying white boundary condition directly is presented and applied to thermal neutron transport problems. The disadvantage factors computed are compared with their counterparts calculated by S N methods with both direct and indirect application of white boundary condition. The results of the ABH and collision probability method with indirect application of white boundary condition are also considered and comparisons with benchmark Monte Carlo results are carried out. The studies show that the proposed formulation is capable of calculating thermal disadvantage factor with sufficient accuracy without resorting to the fictitious scattering outer shell approximation associated with the indirect application of the white boundary condition in collision probability solutions

  12. The application of advanced rotor (performance) methods for design calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bussel, G.J.W. van [Delft Univ. of Technology, Inst. for Wind Energy, Delft (Netherlands)

    1997-08-01

    The calculation of loads and performance of wind turbine rotors has been a topic for research over the last century. The principles for the calculation of loads on rotor blades with a given specific geometry, as well as the development of optimal shaped rotor blades have been published in the decades that significant aircraft development took place. Nowadays advanced computer codes are used for specific problems regarding modern aircraft, and application to wind turbine rotors has also been performed occasionally. The engineers designing rotor blades for wind turbines still use methods based upon global principles developed in the beginning of the century. The question what to expect in terms of the type of methods to be applied in a design environment for the near future is addressed here. (EG) 14 refs.

  13. Problems in radiation shielding calculations with Monte Carlo methods

    International Nuclear Information System (INIS)

    Ueki, Kohtaro

    1985-01-01

    The Monte Carlo method is a very useful tool for solving a large class of radiation transport problem. In contrast with deterministic method, geometric complexity is a much less significant problem for Monte Carlo calculations. However, the accuracy of Monte Carlo calculations is of course, limited by statistical error of the quantities to be estimated. In this report, we point out some typical problems to solve a large shielding system including radiation streaming. The Monte Carlo coupling technique was developed to settle such a shielding problem accurately. However, the variance of the Monte Carlo results using the coupling technique of which detectors were located outside the radiation streaming, was still not enough. So as to bring on more accurate results for the detectors located outside the streaming and also for a multi-legged-duct streaming problem, a practicable way of ''Prism Scattering technique'' is proposed in the study. (author)

  14. Benchmark calculations for evaluation methods of gas volumetric leakage rate

    International Nuclear Information System (INIS)

    Asano, R.; Aritomi, M.; Matsuzaki, M.

    1998-01-01

    A containment function of radioactive materials transport casks is essential for safe transportation to prevent the radioactive materials from being released into environment. Regulations such as IAEA standard determined the limit of radioactivity to be released. Since is not practical for the leakage tests to measure directly the radioactivity release from a package, as gas volumetric leakages rates are proposed in ANSI N14.5 and ISO standards. In our previous works, gas volumetric leakage rates for several kinds of gas from various leaks were measured and two evaluation methods, 'a simple evaluation method' and 'a strict evaluation method', were proposed based on the results. The simple evaluation method considers the friction loss of laminar flow with expansion effect. The strict evaluating method considers an exit loss in addition to the friction loss. In this study, four worked examples were completed for on assumed large spent fuel transport cask (Type B Package) with wet or dry capacity and at three transport conditions; normal transport with intact fuels or failed fuels, and an accident in transport. The standard leakage rates and criteria for two kinds of leak test were calculated for each example by each evaluation method. The following observations are made based upon the calculations and evaluations: the choked flow model of ANSI method greatly overestimates the criteria for tests ; the laminar flow models of both ANSI and ISO methods slightly overestimate the criteria for tests; the above two results are within the design margin for ordinary transport condition and all methods are useful for the evaluation; for severe condition such as failed fuel transportation, it should pay attention to apply a choked flow model of ANSI method. (authors)

  15. General method for final focus system design for circular colliders

    Directory of Open Access Journals (Sweden)

    Riccardo de Maria

    2008-03-01

    Full Text Available Colliders use final focus systems to reduce the transverse beam sizes at the interaction point in order to increase collision event rates. The maximum focal strength (gradient of the quadrupoles, and the maximum beam size in them, together limit the beam size reduction that is possible. The goal of a final focus system design is to find the best compromise between quadrupole aperture and quadrupole gradient, for the magnet technology that is used. This paper develops a design method that identifies the intrinsic limitations of a final focus system, validates the results of the method against realistic designs, and reports its application to the upgrade of the Large Hadron Collider final focus.

  16. Aerodynamic calculational methods for curved-blade Darrieus VAWT WECS

    Science.gov (United States)

    Templin, R. J.

    1985-03-01

    Calculation of aerodynamic performance and load distributions for curved-blade wind turbines is discussed. Double multiple stream tube theory, and the uncertainties that remain in further developing adequate methods are considered. The lack of relevant airfoil data at high Reynolds numbers and high angles of attack, and doubts concerning the accuracy of models of dynamic stall are underlined. Wind tunnel tests of blade airbrake configurations are summarized.

  17. Testing the QA Method for Calculating Jet v_{2}

    CERN Document Server

    Mueller, Jason

    2014-01-01

    For the summer, I was assigned to work on the ALICE experiment with Alice Ohlson. I wrote several programs throughout the summer that were used to calculate jet v 2 using a non-standard method described by my supervisor in her Ph.D. thesis. Though the project is not yet complete, significant progress has been made, and the results so far seem promising.

  18. Calculations of pair production by Monte Carlo methods

    International Nuclear Information System (INIS)

    Bottcher, C.; Strayer, M.R.

    1991-01-01

    We describe some of the technical design issues associated with the production of particle-antiparticle pairs in very large accelerators. To answer these questions requires extensive calculation of Feynman diagrams, in effect multi-dimensional integrals, which we evaluate by Monte Carlo methods on a variety of supercomputers. We present some portable algorithms for generating random numbers on vector and parallel architecture machines. 12 refs., 14 figs

  19. An analytical method for neutron thermalization calculations in heterogenous reactors

    Energy Technology Data Exchange (ETDEWEB)

    Pop-Jordanov, J [Boris Kidric Institute of Nuclear Sciences, Vinca, Belgrade (Yugoslavia)

    1965-07-01

    It is well known that the use of the diffusion approximation for stumethods are rather laborious and require the use of large digital computers. In this paper, the use of the diffusion approximation in absorbing media has been avoided, but the treatment remained analytical, thus simplifying practical calculations.

  20. An analytical method for neutron thermalization calculations in heterogenous reactors

    International Nuclear Information System (INIS)

    Pop-Jordanov, J.

    1965-01-01

    It is well known that the use of the diffusion approximation for studying neutron thermalization in heterogeneous reactors may result in considerable errors. On the other hand, more exact numerical methods are rather laborious and require the use of large digital computers. In this paper, the use of the diffusion approximation in absorbing media has been avoided, but the treatment remained analytical, thus simplifying practical calculations

  1. Higher order methods for burnup calculations with Bateman solutions

    International Nuclear Information System (INIS)

    Isotalo, A.E.; Aarnio, P.A.

    2011-01-01

    Highlights: → Average microscopic reaction rates need to be estimated at each step. → Traditional predictor-corrector methods use zeroth and first order predictions. → Increasing predictor order greatly improves results. → Increasing corrector order does not improve results. - Abstract: A group of methods for burnup calculations solves the changes in material compositions by evaluating an explicit solution to the Bateman equations with constant microscopic reaction rates. This requires predicting representative averages for the one-group cross-sections and flux during each step, which is usually done using zeroth and first order predictions for their time development in a predictor-corrector calculation. In this paper we present the results of using linear, rather than constant, extrapolation on the predictor and quadratic, rather than linear, interpolation on the corrector. Both of these are done by using data from the previous step, and thus do not affect the stepwise running time. The methods were tested by implementing them into the reactor physics code Serpent and comparing the results from four test cases to accurate reference results obtained with very short steps. Linear extrapolation greatly improved results for thermal spectra and should be preferred over the constant one currently used in all Bateman solution based burnup calculations. The effects of using quadratic interpolation on the corrector were, on the other hand, predominantly negative, although not enough so to conclusively decide between the linear and quadratic variants.

  2. Comparison of optimization methods for electronic-structure calculations

    International Nuclear Information System (INIS)

    Garner, J.; Das, S.G.; Min, B.I.; Woodward, C.; Benedek, R.

    1989-01-01

    The performance of several local-optimization methods for calculating electronic structure is compared. The fictitious first-order equation of motion proposed by Williams and Soler is integrated numerically by three procedures: simple finite-difference integration, approximate analytical integration (the Williams-Soler algorithm), and the Born perturbation series. These techniques are applied to a model problem for which exact solutions are known, the Mathieu equation. The Williams-Soler algorithm and the second Born approximation converge equally rapidly, but the former involves considerably less computational effort and gives a more accurate converged solution. Application of the method of conjugate gradients to the Mathieu equation is discussed

  3. MATH: A Scientific Tool for Numerical Methods Calculation and Visualization

    Directory of Open Access Journals (Sweden)

    Henrich Glaser-Opitz

    2016-02-01

    Full Text Available MATH is an easy to use application for various numerical methods calculations with graphical user interface and integrated plotting tool written in Qt with extensive use of Qwt library for plotting options and use of Gsl and MuParser libraries as a numerical and parser helping libraries. It can be found at http://sourceforge.net/projects/nummath. MATH is a convenient tool for use in education process because of its capability of showing every important step in solution process to better understand how it is done. MATH also enables fast comparison of similar method speed and precision.

  4. Nuclear calculation methods for light water moderated reactors

    International Nuclear Information System (INIS)

    Hicks, D.

    1961-02-01

    This report is intended as an introductory review. After a brief discussion of problems encountered in the nuclear design of water moderated reactors a comprehensive scheme of calculations is described. This scheme is based largely on theoretical methods and computer codes developed in the U.S.A. but some previously unreported developments made in this country are also described. It is shown that the effective reproduction factor of simple water moderated lattices may be estimated to an accuracy of approximately 1%. Methods for treating water gap flux peaking and control absorbers are presented in some detail, together with a brief discussion of temperature coefficients, void coefficients and burn-up problems. (author)

  5. Calculation of degenerated Eigenmodes with modified power method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Peng; Lee, Hyun Suk; Lee, Deok Jung [School of Mechanical and Nuclear Engineering, Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2017-02-15

    The modified power method has been studied by many researchers to calculate the higher Eigenmodes and accelerate the convergence of the fundamental mode. Its application to multidimensional problems may be unstable due to degenerated or near-degenerated Eigenmodes. Complex Eigenmode solutions are occasionally encountered in such cases, and the shapes of the corresponding eigenvectors may change during the simulation. These issues must be addressed for the successful implementation of the modified power method. Complex components are examined and an approximation method to eliminate the usage of the complex numbers is provided. A technique to fix the eigenvector shapes is also provided. The performance of the methods for dealing with those aforementioned problems is demonstrated with two dimensional one group and three dimensional one group homogeneous diffusion problems.

  6. Improvement of correlated sampling Monte Carlo methods for reactivity calculations

    International Nuclear Information System (INIS)

    Nakagawa, Masayuki; Asaoka, Takumi

    1978-01-01

    Two correlated Monte Carlo methods, the similar flight path and the identical flight path methods, have been improved to evaluate up to the second order change of the reactivity perturbation. Secondary fission neutrons produced by neutrons having passed through perturbed regions in both unperturbed and perturbed systems are followed in a way to have a strong correlation between secondary neutrons in both the systems. These techniques are incorporated into the general purpose Monte Carlo code MORSE, so as to be able to estimate also the statistical error of the calculated reactivity change. The control rod worths measured in the FCA V-3 assembly are analyzed with the present techniques, which are shown to predict the measured values within the standard deviations. The identical flight path method has revealed itself more useful than the similar flight path method for the analysis of the control rod worth. (auth.)

  7. MERSENNE AND HADAMARD MATRICES CALCULATION BY SCARPIS METHOD

    Directory of Open Access Journals (Sweden)

    N. A. Balonin

    2014-05-01

    Full Text Available Purpose. The paper deals with the problem of basic generalizations of Hadamard matrices associated with maximum determinant matrices or not optimal by determinant matrices with orthogonal columns (weighing matrices, Mersenne and Euler matrices, ets.; calculation methods for the quasi-orthogonal local maximum determinant Mersenne matrices are not studied enough sufficiently. The goal of this paper is to develop the theory of Mersenne and Hadamard matrices on the base of generalized Scarpis method research. Methods. Extreme solutions are found in general by minimization of maximum for absolute values of the elements of studied matrices followed by their subsequent classification according to the quantity of levels and their values depending on orders. Less universal but more effective methods are based on structural invariants of quasi-orthogonal matrices (Silvester, Paley, Scarpis methods, ets.. Results. Generalizations of Hadamard and Belevitch matrices as a family of quasi-orthogonal matrices of odd orders are observed; they include, in particular, two-level Mersenne matrices. Definitions of section and layer on the set of generalized matrices are proposed. Calculation algorithms for matrices of adjacent layers and sections by matrices of lower orders are described. Approximation examples of the Belevitch matrix structures up to 22-nd critical order by Mersenne matrix of the third order are given. New formulation of the modified Scarpis method to approximate Hadamard matrices of high orders by lower order Mersenne matrices is proposed. Williamson method is described by example of one modular level matrices approximation by matrices with a small number of levels. Practical relevance. The efficiency of developing direction for the band-pass filters creation is justified. Algorithms for Mersenne matrices design by Scarpis method are used in developing software of the research program complex. Mersenne filters are based on the suboptimal by

  8. Brief note on the statistical calculation of final continuum reaction cross sections of light nuclides

    International Nuclear Information System (INIS)

    Murata, Toru

    2003-01-01

    The level density parameters are determined to reproduce level structure and/or resonance level spacing of the nucleus. In the statistical compound nucleus model, cross sections to discrete levels decrease abruptly, and continuum level cross section increase strongly above the energy point where the continuum levels switched on. In the present study, for the nucleus which level scheme were well determined up to higher excitation energy more than 10 MeV, discrete level cross sections were calculated and summed up and compared with the cross section to the assumed continuum level corresponding to the discrete levels above several MeV excitation energy. Calculation of the (n, n') cross sections were made with CASTHY code of Moldauer model option using level density parameters determined with former method. It is shown that the assumed continuum cross section is fairly large compared with the summed up cross section. Origins of the discrepancy were discussed. (J.P.N.)

  9. Application of Indenting Method for Calculation of Activation Energy

    International Nuclear Information System (INIS)

    Kim, Jong-Seog; Kim, Tae-Ryong

    2006-01-01

    For the calculation of activation energy of cable materials, we used to apply the break-elongation test in accordance with ASTM D412(Stand Test Methods for Rubber Properties in Tension). For the cable jacket and insulation which have regular thickness, break-elongation test had been preferred since it showed linear character in the activation energy curve. But, for the cable which has irregular thickness or rugged surface of cable inside, break-elongation test show scattered data which can not be used for the calculation of activation energy. It is not easy to prepare break-elongation specimen for the cable smaller than 13mm diameter in accordance with ASTM D412. In the cases of above, we sometime use TGA method which heat the specimen from 50 .deg. C to 700 .deg. C at heating rates of 10, 15, 20 .deg. C/min. But, TGA is suspected for the representative of natural aging in the plant since it measure the weight decreasing rate during burning which may have different aging mechanism with that of natural aging. To solve above problems, we investigated alternatives such as indenter test. Indenter test is very convenient since it does not ask for a special test specimen as the break-elongation test does. Regular surface of cable outside is the only requirement of indenter test. Experience of activation energy calculation by using the indenter test is described herein

  10. A Novel TRM Calculation Method by Probabilistic Concept

    Science.gov (United States)

    Audomvongseree, Kulyos; Yokoyama, Akihiko; Verma, Suresh Chand; Nakachi, Yoshiki

    In a new competitive environment, it becomes possible for the third party to access a transmission facility. From this structure, to efficiently manage the utilization of the transmission network, a new definition about Available Transfer Capability (ATC) has been proposed. According to the North American ElectricReliability Council (NERC)’s definition, ATC depends on several parameters, i. e. Total Transfer Capability (TTC), Transmission Reliability Margin (TRM), and Capacity Benefit Margin (CBM). This paper is focused on the calculation of TRM which is one of the security margin reserved for any uncertainty of system conditions. The TRM calculation by probabilistic method is proposed in this paper. Based on the modeling of load forecast error and error in transmission line limitation, various cases of transmission transfer capability and its related probabilistic nature can be calculated. By consideration of the proposed concept of risk analysis, the appropriate required amount of TRM can be obtained. The objective of this research is to provide realistic information on the actual ability of the network which may be an alternative choice for system operators to make an appropriate decision in the competitive market. The advantages of the proposed method are illustrated by application to the IEEJ-WEST10 model system.

  11. Bulk Electric Load Cost Calculation Methods: Iraqi Network Comparative Study

    Directory of Open Access Journals (Sweden)

    Qais M. Alias

    2016-09-01

    Full Text Available It is vital in any industry to regain the spent capitals plus running costs and a margin of profits for the industry to flourish. The electricity industry is an everyday life touching industry which follows the same finance-economic strategy. Cost allocation is a major issue in all sectors of the electric industry, viz, generation, transmission and distribution. Generation and distribution service costing’s well documented in the literature, while the transmission share is still of need for research. In this work, the cost of supplying a bulk electric load connected to the EHV system is calculated. A sample basic lump-average method is used to provide a rough costing guide. Also, two transmission pricing methods are employed, namely, the postage-stamp and the load-flow based MW-distance methods to calculate transmission share in the total cost of each individual bulk load. The three costing methods results are then analyzed and compared for the 400kV Iraqi power grid considered for a case study.

  12. Evaluation of cost estimates and calculation methods used by SKB

    International Nuclear Information System (INIS)

    1994-01-01

    The Swedish Nuclear Fuel Management Co. (SKB) has estimated the costs for decommissioning the swedish nuclear power plants and managing the nuclear wastes in a 'traditional' manner i.e. by handling uncertainties through percentage additions. A 'normal' addition is used for uncertainties in specified technical systems. 'Extra' additions are used for systems uncertainties. An alternative method is suggested, using top-down principles for uncertainties, which should be applied successively, giving higher precision as the knowledge accumulates. This type of calculation can help project managers to identify and deal with areas common to different partial projects. A first step in this direction would be to perform sensitivity analyses for the most important calculation parameters. 21 refs

  13. A density gradient theory based method for surface tension calculations

    DEFF Research Database (Denmark)

    Liang, Xiaodong; Michelsen, Michael Locht; Kontogeorgis, Georgios

    2016-01-01

    The density gradient theory has been becoming a widely used framework for calculating surface tension, within which the same equation of state is used for the interface and bulk phases, because it is a theoretically sound, consistent and computationally affordable approach. Based on the observation...... that the optimal density path from the geometric mean density gradient theory passes the saddle point of the tangent plane distance to the bulk phases, we propose to estimate surface tension with an approximate density path profile that goes through this saddle point. The linear density gradient theory, which...... assumes linearly distributed densities between the two bulk phases, has also been investigated. Numerical problems do not occur with these density path profiles. These two approximation methods together with the full density gradient theory have been used to calculate the surface tension of various...

  14. Charged-particle calculations using Boltzmann transport methods

    International Nuclear Information System (INIS)

    Hoffman, T.J.; Dodds, H.L. Jr.; Robinson, M.T.; Holmes, D.K.

    1981-01-01

    Several aspects of radiation damage effects in fusion reactor neutron and ion irradiation environments are amenable to treatment by transport theory methods. In this paper, multigroup transport techniques are developed for the calculation of charged particle range distributions, reflection coefficients, and sputtering yields. The Boltzmann transport approach can be implemented, with minor changes, in standard neutral particle computer codes. With the multigroup discrete ordinates code, ANISN, determination of ion and target atom distributions as functions of position, energy, and direction can be obtained without the stochastic error associated with atomistic computer codes such as MARLOWE and TRIM. With the multigroup Monte Carlo code, MORSE, charged particle effects can be obtained for problems associated with very complex geometries. Results are presented for several charged particle problems. Good agreement is obtained between quantities calculated with the multigroup approach and those obtained experimentally or by atomistic computer codes

  15. A comparison of Nodal methods in neutron diffusion calculations

    Energy Technology Data Exchange (ETDEWEB)

    Tavron, Barak [Israel Electric Company, Haifa (Israel) Nuclear Engineering Dept. Research and Development Div.

    1996-12-01

    The nuclear engineering department at IEC uses in the reactor analysis three neutron diffusion codes based on nodal methods. The codes, GNOMERl, ADMARC2 and NOXER3 solve the neutron diffusion equation to obtain flux and power distributions in the core. The resulting flux distributions are used for the furl cycle analysis and for fuel reload optimization. This work presents a comparison of the various nodal methods employed in the above codes. Nodal methods (also called Coarse-mesh methods) have been designed to solve problems that contain relatively coarse areas of homogeneous composition. In the nodal method parts of the equation that present the state in the homogeneous area are solved analytically while, according to various assumptions and continuity requirements, a general solution is sought out. Thus efficiency of the method for this kind of problems, is very high compared with the finite element and finite difference methods. On the other hand, using this method one can get only approximate information about the node vicinity (or coarse-mesh area, usually a feel assembly of a 20 cm size). These characteristics of the nodal method make it suitable for feel cycle analysis and reload optimization. This analysis requires many subsequent calculations of the flux and power distributions for the feel assemblies while there is no need for detailed distribution within the assembly. For obtaining detailed distribution within the assembly methods of power reconstruction may be applied. However homogenization of feel assembly properties, required for the nodal method, may cause difficulties when applied to fuel assemblies with many absorber rods, due to exciting strong neutron properties heterogeneity within the assembly. (author).

  16. An integral nodal variational method for multigroup criticality calculations

    International Nuclear Information System (INIS)

    Lewis, E.E.; Tsoulfanidis, N.

    2003-01-01

    An integral formulation of the variational nodal method is presented and applied to a series of benchmark critically problems. The method combines an integral transport treatment of the even-parity flux within the spatial node with an odd-parity spherical harmonics expansion of the Lagrange multipliers at the node interfaces. The response matrices that result from this formulation are compatible with those in the VARIANT code at Argonne National Laboratory. Either homogeneous or heterogeneous nodes may be employed. In general, for calculations requiring higher-order angular approximations, the integral method yields solutions with comparable accuracy while requiring substantially less CPU time and memory than the standard spherical harmonics expansion using the same spatial approximations. (author)

  17. A sub-structure method for multidimensional integral transport calculations

    International Nuclear Information System (INIS)

    Kavenoky, A.; Stankovski, Z.

    1983-03-01

    A new method has been developed for fine structure burn-up calculations of very heterogeneous large size media. It is a generalization of the well-known surface-source method, allowing coupling actual two-dimensional heterogeneous assemblies, called sub-structures. The method has been applied to a rectangular medium, divided into sub-structures, containing rectangular and/or cylindrical fuel, moderator and structure elements. The sub-structures are divided into homogeneous zones. A zone-wise flux expansion is used to formulate a direct collision probability problem within it (linear or flat flux expansion in the rectangular zones, flat flux in the others). The coupling of the sub-structures is performed by making extra assumptions on the currents entering and leaving the interfaces. The accuracies and computing times achieved are illustrated by numerical results on two benchmark problems

  18. Nested element method in multidimensional neutron diffusion calculations

    International Nuclear Information System (INIS)

    Altiparmakov, D.V.

    1983-01-01

    A new numerical method is developed that is particularly efficient in solving the multidimensional neutron diffusion equation in geometrically complex systems. The needs for a generally applicable and fast running computer code have stimulated the inroad of a nonclassical (R-function) numerical method into the nuclear field. By using the R-functions, the geometrical components of the diffusion problem are a priori analytically implemented into the approximate solution. The class of functions, to which the approximate solution belongs, is chosen as close to the exact solution class as practically acceptable from the time consumption point of view. That implies a drastic reduction of the number of degrees of freedom, compared to the other methods. Furthermore, the reduced number of degrees of freedom enables calculation of large multidimensional problems on small computers

  19. A unique manual method for emergency offsite dose calculations

    International Nuclear Information System (INIS)

    Wildner, T.E.; Carson, B.H.; Shank, K.E.

    1987-01-01

    This paper describes a manual method developed for performance of emergency offsite dose calculations for PP and L's Susquehanna Steam Electric Station. The method is based on a three-part carbonless form. The front page guides the user through selection of the appropriate accident case and inclusion of meteorological and effluent data data. By circling the applicable accident descriptors, the user circles the dose factors on pages 2 and 3 which are then simply multiplied to yield the whole body and thyroid dose rates at the plant boundary, two, five, and ten miles. The process used to generate the worksheet is discussed, including the method used to incorporate the observed terrain effects on airflow patterns caused by the Susquehanna River Valley topography

  20. Application of wavelet scaling function expansion continuous-energy resonance calculation method to MOX fuel problem

    International Nuclear Information System (INIS)

    Yang, W.; Wu, H.; Cao, L.

    2012-01-01

    More and more MOX fuels are used in all over the world in the past several decades. Compared with UO 2 fuel, it contains some new features. For example, the neutron spectrum is harder and more resonance interference effects within the resonance energy range are introduced because of more resonant nuclides contained in the MOX fuel. In this paper, the wavelets scaling function expansion method is applied to study the resonance behavior of plutonium isotopes within MOX fuel. Wavelets scaling function expansion continuous-energy self-shielding method is developed recently. It has been validated and verified by comparison to Monte Carlo calculations. In this method, the continuous-energy cross-sections are utilized within resonance energy, which means that it's capable to solve problems with serious resonance interference effects without iteration calculations. Therefore, this method adapts to treat the MOX fuel resonance calculation problem natively. Furthermore, plutonium isotopes have fierce oscillations of total cross-section within thermal energy range, especially for 240 Pu and 242 Pu. To take thermal resonance effect of plutonium isotopes into consideration the wavelet scaling function expansion continuous-energy resonance calculation code WAVERESON is enhanced by applying the free gas scattering kernel to obtain the continuous-energy scattering source within thermal energy range (2.1 eV to 4.0 eV) contrasting against the resonance energy range in which the elastic scattering kernel is utilized. Finally, all of the calculation results of WAVERESON are compared with MCNP calculation. (authors)

  1. Expansion and compression shock wave calculation in pipes with the C.V.M. numerical method

    International Nuclear Information System (INIS)

    Raymond, P.; Caumette, P.; Le Coq, G.; Libmann, M.

    1983-03-01

    The Control Variables Method for fluid transients computations has been used to compute expansion and compression shock waves propagations. In this paper, first analytical solutions for shock wave and rarefaction wave propagation are detailed. Then after a rapid description of the C.V.M. technique and its stability and monotonicity properties, we will present some results about standard shock tube problem, reflection of shock wave, finally a comparison between experimental results obtained on the ELF facility and calculations is given

  2. [Evaluation of methods to calculate dialysis dose in daily hemodialysis].

    Science.gov (United States)

    Maduell, F; Gutiérrez, E; Navarro, V; Torregrosa, E; Martínez, A; Rius, A

    2003-01-01

    Daily dialysis has shown excellent clinical results because a higher frequency of dialysis is more physiological. Different methods have been described to calculate dialysis dose which take into consideration change in frequency. The aim of this study was to calculate all dialysis dose possibilities and evaluate the better and practical options. Eight patients, 6 males and 2 females, on standard 4 to 5 hours thrice weekly on-line hemodiafiltration (S-OL-HDF) were switched to daily on-line hemodiafiltration (D-OL-HDF) 2 to 2.5 hours six times per week. Dialysis parameters were identical during both periods and only frequency and dialysis time of each session were changed. Time average concentration (TAC), time average deviation (TAD), normalized protein catabolic rate (nPCR), Kt/V, equilibrated Kt/V (eKt/V), equivalent renal urea clearance (EKR), standard Kt/V (stdKt/V), urea reduction ratio (URR), hemodialysis product and time off dialysis were measured. Daily on-line hemodiafiltration was well accepted and tolerated. Patients maintained the same TAC although TAD decreased from 9.7 +/- 2 in baseline to a 6.2 +/- 2 mg/dl after six months, p time off dialysis was reduced to half. Dialysis frequency is an important urea kinetic parameter which there are to take in consideration. It's necessary to use EKR, stdKt/V or weekly URR to calculate dialysis dose for an adequate comparison between different frequency dialysis schedules.

  3. Study on calculation methods for the effective delayed neutron fraction

    International Nuclear Information System (INIS)

    Irwanto, Dwi; Obara, Toru; Chiba, Go; Nagaya, Yasunobu

    2011-03-01

    The effective delayed neutron fraction β eff is one of the important neutronic parameters from a view point of a reactor kinetics. Several Monte-Carlo-based methods to estimate β eff have been proposed to date. In order to quantify the accuracy of these methods, we study calculation methods for β eff by analyzing various fast neutron systems including the bare spherical systems (Godiva, Jezebel, Skidoo, Jezebel-240), the reflective spherical systems (Popsy, Topsy, Flattop-23), MASURCA-R2 and MASURCA-ZONA2, and FCA XIX-1, XIX-2 and XIX-3. These analyses are performed by using SLAROM-UF and CBG for the deterministic method and MVP-II for the Monte Carlo method. We calculate β eff with various definitions such as the fundamental value β 0 , the standard definition, Nauchi's definition and Meulekamp's definition, and compare these results with each other. Through the present study, we find the following: The largest difference among the standard definition of β eff , Nauchi's β eff and Meulekamp's β eff is approximately 10%. The fundamental value β 0 is quite larger than the others in several cases. For all the cases, Meulekamp's β eff is always higher than Nauchi's β eff . This is because Nauchi's β eff considers the average neutron multiplicity value per fission which is large in the high energy range (1MeV-10MeV), while the definition of Meulekamp's β eff does not include this parameter. Furthermore, we evaluate the multi-generation effect on β eff values and demonstrate that this effect should be considered to obtain the standard definition values of β eff . (author)

  4. A Method for Calculating the Mean Orbits of Meteor Streams

    Science.gov (United States)

    Voloshchuk, Yu. I.; Kashcheev, B. L.

    An examination of the published catalogs of orbits of meteor streams and of a large number of works devoted to the selection of streams, their analysis and interpretation, showed that elements of stream orbits are calculated, as a rule, as arithmetical (sometimes, weighed) sample means. On the basis of these means, a search for parent bodies, a study of the evolution of swarms generating these streams, an analysis of one-dimensional and multidimensional distributions of these elements, etc., are performed. We show that systematic errors in the estimates of elements of the mean orbits are present in each of the catalogs. These errors are caused by the formal averaging of orbital elements over the sample, while ignoring the fact that they represent not only correlated, but dependent quantities, with nonlinear, in most cases, interrelations between them. Numerous examples are given of such inaccuracies, in particular, the cases where the "mean orbit of the stream" recorded by ground-based techniques does not cross the Earth's orbit. We suggest the computation algorithm, in which the averaging over the sample is carried out at the initial stage of the calculation of the mean orbit, and only for the variables required for subsequent calculations. After this, the known astrometric formulas are used to sequentially calculate all other parameters of the stream, considered now as a standard orbit. Variance analysis is used to estimate the errors in orbital elements of the streams, in the case that their orbits are obtained by averaging the orbital elements of meteoroids forming the stream, without taking into account their interdependence. The results obtained in this analysis indicate the behavior of systematic errors in the elements of orbits of meteor streams. As an example, the effect of the incorrect computation method on the distribution of elements of the stream orbits close to the orbits of asteroids of the Apollo, Aten, and Amor groups (AAA asteroids) is examined.

  5. Efficient parallel implicit methods for rotary-wing aerodynamics calculations

    Science.gov (United States)

    Wissink, Andrew M.

    Euler/Navier-Stokes Computational Fluid Dynamics (CFD) methods are commonly used for prediction of the aerodynamics and aeroacoustics of modern rotary-wing aircraft. However, their widespread application to large complex problems is limited lack of adequate computing power. Parallel processing offers the potential for dramatic increases in computing power, but most conventional implicit solution methods are inefficient in parallel and new techniques must be adopted to realize its potential. This work proposes alternative implicit schemes for Euler/Navier-Stokes rotary-wing calculations which are robust and efficient in parallel. The first part of this work proposes an efficient parallelizable modification of the Lower Upper-Symmetric Gauss Seidel (LU-SGS) implicit operator used in the well-known Transonic Unsteady Rotor Navier Stokes (TURNS) code. The new hybrid LU-SGS scheme couples a point-relaxation approach of the Data Parallel-Lower Upper Relaxation (DP-LUR) algorithm for inter-processor communication with the Symmetric Gauss Seidel algorithm of LU-SGS for on-processor computations. With the modified operator, TURNS is implemented in parallel using Message Passing Interface (MPI) for communication. Numerical performance and parallel efficiency are evaluated on the IBM SP2 and Thinking Machines CM-5 multi-processors for a variety of steady-state and unsteady test cases. The hybrid LU-SGS scheme maintains the numerical performance of the original LU-SGS algorithm in all cases and shows a good degree of parallel efficiency. It experiences a higher degree of robustness than DP-LUR for third-order upwind solutions. The second part of this work examines use of Krylov subspace iterative solvers for the nonlinear CFD solutions. The hybrid LU-SGS scheme is used as a parallelizable preconditioner. Two iterative methods are tested, Generalized Minimum Residual (GMRES) and Orthogonal s-Step Generalized Conjugate Residual (OSGCR). The Newton method demonstrates good

  6. Method for calculating annual energy efficiency improvement of TV sets

    International Nuclear Information System (INIS)

    Varman, M.; Mahlia, T.M.I.; Masjuki, H.H.

    2006-01-01

    The popularization of 24 h pay-TV, interactive video games, web-TV, VCD and DVD are poised to have a large impact on overall TV electricity consumption in the Malaysia. Following this increased consumption, energy efficiency standard present a highly effective measure for decreasing electricity consumption in the residential sector. The main problem in setting energy efficiency standard is identifying annual efficiency improvement, due to the lack of time series statistical data available in developing countries. This study attempts to present a method of calculating annual energy efficiency improvement for TV set, which can be used for implementing energy efficiency standard for TV sets in Malaysia and other developing countries. Although the presented result is only an approximation, definitely it is one of the ways of accomplishing energy standard. Furthermore, the method can be used for other appliances without any major modification

  7. Method for calculating annual energy efficiency improvement of TV sets

    Energy Technology Data Exchange (ETDEWEB)

    Varman, M. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Mahlia, T.M.I. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)]. E-mail: indra@um.edu.my; Masjuki, H.H. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)

    2006-10-15

    The popularization of 24 h pay-TV, interactive video games, web-TV, VCD and DVD are poised to have a large impact on overall TV electricity consumption in the Malaysia. Following this increased consumption, energy efficiency standard present a highly effective measure for decreasing electricity consumption in the residential sector. The main problem in setting energy efficiency standard is identifying annual efficiency improvement, due to the lack of time series statistical data available in developing countries. This study attempts to present a method of calculating annual energy efficiency improvement for TV set, which can be used for implementing energy efficiency standard for TV sets in Malaysia and other developing countries. Although the presented result is only an approximation, definitely it is one of the ways of accomplishing energy standard. Furthermore, the method can be used for other appliances without any major modification.

  8. A new method for calculation of an air quality index

    Energy Technology Data Exchange (ETDEWEB)

    Ilvessalo, P. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1995-12-31

    Air quality measurement programs in Finnish towns have expanded during the last few years. As a result of this it is more and more difficult to make use of all the measured concentration data. Citizens of Finnish towns are nowadays taking more of an interest in the air quality of their surroundings. The need to describe air quality in a simplified form has increased. Air quality indices permit the presentation of air quality data in such a way that prevailing conditions are more easily understandable than when using concentration data as such. Using an air quality index always means that some of the information about concentrations of contaminants in the air will be lost. How much information is possible to extract from a single index number depends on the calculation method. A new method for the calculation of an air quality index has been developed. This index always indicates the overstepping of an air quality guideline level. The calculation of this air quality index is performed using the concentrations of all the contaminants measured. The index gives information both about the prevailing air quality and also the short-term trend. It can also warn about the expected exceeding of guidelines due to one or several contaminants. The new index is especially suitable for the real-time monitoring and notification of air quality values. The behaviour of the index was studied using material from a measurement period in the spring of 1994 in Kaepylae, Helsinki. Material from a pre-operational period in the town of Oulu was also available. (author)

  9. A new method for calculation of an air quality index

    Energy Technology Data Exchange (ETDEWEB)

    Ilvessalo, P [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1996-12-31

    Air quality measurement programs in Finnish towns have expanded during the last few years. As a result of this it is more and more difficult to make use of all the measured concentration data. Citizens of Finnish towns are nowadays taking more of an interest in the air quality of their surroundings. The need to describe air quality in a simplified form has increased. Air quality indices permit the presentation of air quality data in such a way that prevailing conditions are more easily understandable than when using concentration data as such. Using an air quality index always means that some of the information about concentrations of contaminants in the air will be lost. How much information is possible to extract from a single index number depends on the calculation method. A new method for the calculation of an air quality index has been developed. This index always indicates the overstepping of an air quality guideline level. The calculation of this air quality index is performed using the concentrations of all the contaminants measured. The index gives information both about the prevailing air quality and also the short-term trend. It can also warn about the expected exceeding of guidelines due to one or several contaminants. The new index is especially suitable for the real-time monitoring and notification of air quality values. The behaviour of the index was studied using material from a measurement period in the spring of 1994 in Kaepylae, Helsinki. Material from a pre-operational period in the town of Oulu was also available. (author)

  10. A drainage data-based calculation method for coalbed permeability

    International Nuclear Information System (INIS)

    Lai, Feng-peng; Li, Zhi-ping; Fu, Ying-kun; Yang, Zhi-hao

    2013-01-01

    This paper establishes a drainage data-based calculation method for coalbed permeability. The method combines material balance and production equations. We use a material balance equation to derive the average pressure of the coalbed in the production process. The dimensionless water production index is introduced into the production equation for the water production stage. In the subsequent stage, which uses both gas and water, the gas and water production ratio is introduced to eliminate the effect of flush-flow radius, skin factor, and other uncertain factors in the calculation of coalbed methane permeability. The relationship between permeability and surface cumulative liquid production can be described as a single-variable cubic equation by derivation. The trend shows that the permeability initially declines and then increases after ten wells in the southern Qinshui coalbed methane field. The results show an exponential relationship between permeability and cumulative water production. The relationship between permeability and cumulative gas production is represented by a linear curve and that between permeability and surface cumulative liquid production is represented by a cubic polynomial curve. The regression result of the permeability and surface cumulative liquid production agrees with the theoretical mathematical relationship. (paper)

  11. Physics methods for calculating light water reactor increased performances

    International Nuclear Information System (INIS)

    Vandenberg, C.; Charlier, A.

    1988-01-01

    The intensive use of light water reactors (LWRs) has induced modification of their characteristics and performances in order to improve fissile material utilization and to increase their availability and flexibility under operation. From the conceptual point of view, adequate methods must be used to calculate core characteristics, taking into account present design requirements, e.g., use of burnable poison, plutonium recycling, etc. From the operational point of view, nuclear plants that have been producing a large percentage of electricity in some countries must adapt their planning to the need of the electrical network and operate on a load-follow basis. Consequently, plant behavior must be predicted and accurately followed in order to improve the plant's capability within safety limits. The Belgonucleaire code system has been developed and extensively validated. It is an accurate, flexible, easily usable, fast-running tool for solving the problems related to LWR technology development. The methods and validation of the two computer codes LWR-WIMS and MICROLUX, which are the main components of the physics calculation system, are explained

  12. Calculating the vulnerability of synthetic polymers to autoignition during nuclear flash. Final report

    International Nuclear Information System (INIS)

    Hickman, R.; Reitter, T.

    1985-01-01

    The purpose of our investigation was to determine if the rapid progression of fire to flashover conditions in a furnished room, observed in a 1953 nuclear weapons test at the Nevada Test Site (the Encore Event), might be typical behavior rather than an aberration. If flashover under such conditions is indeed likely, this phenomenon is worth pursuing in view of the increased threat to buildings and human life from possible large-scale fires. We placed special emphasis on fires that occurred in modern rooms, i.e., ones furnished with upholstery and drapery materials made from synthetic polymers. Examination of photochemical processes showed them to be an unlikely explanation, either in Encore or in the future. Our calculation of rapid radiant-heating behavior of a few materials demonstrated that fabrics and fabric-covered foams would exceed their autoignition temperature when exposed to a 25-cal/cm 2 fluence from a 1-Mt air burst weapon. Because synthetic polymers have higher heating values and release heat faster during combustion than do the cellulosics used in the Encore experiment, early flashover should not be unexpected in contemporary households. However, the far-field thermal fluence required would be higher because of the absorption of thermal energy by windows and window coverings. Because of the complexity of the problem, carefully planned, full-scale experiments will be needed to finally answer the question. 39 refs., 9 figs., 8 tabs

  13. Mixed first- and second-order transport method using domain decomposition techniques for reactor core calculations

    International Nuclear Information System (INIS)

    Girardi, E.; Ruggieri, J.M.

    2003-01-01

    The aim of this paper is to present the last developments made on a domain decomposition method applied to reactor core calculations. In this method, two kind of balance equation with two different numerical methods dealing with two different unknowns are coupled. In the first part the two balance transport equations (first order and second order one) are presented with the corresponding following numerical methods: Variational Nodal Method and Discrete Ordinate Nodal Method. In the second part, the Multi-Method/Multi-Domain algorithm is introduced by applying the Schwarz domain decomposition to the multigroup eigenvalue problem of the transport equation. The resulting algorithm is then provided. The projection operators used to coupled the two methods are detailed in the last part of the paper. Finally some preliminary numerical applications on benchmarks are given showing encouraging results. (authors)

  14. Calculation Method for the Projection of Future Spent Nuclear Fuel Discharges

    International Nuclear Information System (INIS)

    B. McLeod

    2002-01-01

    This report describes the calculation method developed for the projection of future utility spent nuclear fuel (SNF) discharges in regard to their timing, quantity, burnup, and initial enrichment. This projection method complements the utility-supplied RW-859 data on historic discharges and short-term projections of SNF discharges by providing long-term projections that complete the total life cycle of discharges for each of the current U.S. nuclear power reactors. The method was initially developed in mid-1999 to update the SNF discharge projection associated with the 1995 RW-859 utility survey (CRWMS M and O 1996). and was further developed as described in Rev. 00 of this report (CRWMS M and O 2001a). Primary input to the projection of SNF discharges is the utility projection of the next five discharges from each nuclear unit, which is provided via the revised final version of the Energy Information Administration (EIA) 1998 RW-859 utility survey (EIA 2000a). The projection calculation method is implemented via a set of Excel 97 spreadsheets. These calculations provide the interface between receipt of the utility five-discharge projections that are provided in the RW-859 survey, and the delivery of projected life-cycle SNF discharge quantities and characteristics in the format requisite for performing logistics analysis to support design of the Civilian Radioactive Waste Management System (CRWMS). Calculation method improvements described in this report include the addition of a reactor-specific maximum enrichment-based discharge burnup limit. This limit is the consequence of the enrichment limit, currently 5 percent. which is imposed as a Nuclear Regulatory Commission (NRC) license condition on nuclear fuel fabrication plants. In addition, the calculation method now includes the capability for projecting future nuclear plant power upratings, consistent with many such recent plant uprates and the prospect of additional future uprates. Finally. this report

  15. Domain decomposition methods for core calculations using the MINOS solver

    International Nuclear Information System (INIS)

    Guerin, P.; Baudron, A. M.; Lautard, J. J.

    2007-01-01

    Cell by cell homogenized transport calculations of an entire nuclear reactor core are currently too expensive for industrial applications, even if a simplified transport (SPn) approximation is used. In order to take advantage of parallel computers, we propose here two domain decomposition methods using the mixed dual finite element solver MINOS. The first one is a modal synthesis method on overlapping sub-domains: several Eigenmodes solutions of a local problem on each sub-domain are taken as basis functions used for the resolution of the global problem on the whole domain. The second one is an iterative method based on non-overlapping domain decomposition with Robin interface conditions. At each iteration, we solve the problem on each sub-domain with the interface conditions given by the solutions on the close sub-domains estimated at the previous iteration. For these two methods, we give numerical results which demonstrate their accuracy and their efficiency for the diffusion model on realistic 2D and 3D cores. (authors)

  16. Geothermal Economics Calculator (GEC) - additional modifications to final report as per GTP's request.

    Energy Technology Data Exchange (ETDEWEB)

    Gowda, Varun; Hogue, Michael

    2015-07-17

    This report will discuss the methods and the results from economic impact analysis applied to the development of Enhanced Geothermal Systems (EGS), conventional hydrothermal, low temperature geothermal and coproduced fluid technologies resulting in electric power production. As part of this work, the Energy & Geoscience Institute (EGI) has developed a web-based Geothermal Economics Calculator (Geothermal Economics Calculator (GEC)) tool that is aimed at helping the industry perform geothermal systems analysis and study the associated impacts of specific geothermal investments or technological improvements on employment, energy and environment. It is well-known in the industry that geothermal power projects will generate positive economic impacts for their host regions. Our aim in the assessment of these impacts includes quantification of the increase in overall economic output due to geothermal projects and of the job creation associated with this increase. Such an estimate of economic impacts of geothermal investments on employment, energy and the environment will also help us understand the contributions that the geothermal industry will have in achieving a sustainable path towards energy production.

  17. Calculation of seismic response of a flexible rotor by complex modal method, 1

    International Nuclear Information System (INIS)

    Azuma, Takao; Saito, Shinobu

    1984-01-01

    In rotary machines, at the time of earthquakes, whether the rotating part and stationary part touch or whether the bearings and seals are damaged or not are problems. In order to examine these problems, it is necessary to analyze the seismic response of a rotary shaft or sometimes a casing system. But the conventional analysis methods are unsatisfactory. Accordingly, in the case of a general shaft system supported with slide bearings and on which gyro effect acts, complex modal method must be used. This calculation method is explained in detail in the book of Lancaster, however, when this method is applied to the seismic response of rotary shafts, the calculation time is considerably different according to the method of final integration. In this study, good results were obtained when the method which did not depend on numerical integration was attempted. The equation of motion and its solution, the displacement vector of a foundation, the verification of the calculation program and the example of calculating the seismic response of two coupled rotor shafts are reported. (Kako, I.)

  18. Methods for reactor physics calculations for control rods in fast reactors

    International Nuclear Information System (INIS)

    Grimstone, M.J.; Rowlands, J.L.

    1988-12-01

    The IAEA Specialists' Meeting on ''Methods for Reactor Physics Calculations for Control Rods in Fast Reactors'' was held in Winfrith, United Kingdom, on 6-8 December, 1988. The meeting was attended by 23 participants from nine countries. The purpose of the meeting was to review the current calculational methods and their accuracy as assessed by theoretical studies and comparisons with measurements, and then to identify the requirements for improved methods or additional studies and comparisons. The control rod properties or effects to be considered were their reactivity worths, their effect on the power distribution through the core, and the reaction rates and energy deposition both within and adjacent to the rods. The meeting was divided into five sessions, in the first of which each national delegation presented a brief overview of their programme of work on calculational methods for fast reactor control rods. In the next three sessions a total of seventeen papers were presented describing calculational methods and assessments of their accuracy. The final session was a discussion to draw conclusions regarding the current status of methods and the further developments and validation work required. A separate abstract was prepared for each of the 23 papers presented at the meeting. Refs, figs and tabs

  19. An improved method for calculation of interface pressure force in PLIC-VOF methods

    International Nuclear Information System (INIS)

    Sefollahi, M.; Shirani, E.

    2004-08-01

    Conventional methods for the modeling of surface tension force in Piecewise Linear Interface Calculation-Volume of Fluid (PLIC-VOF) methods, such as Continuum Surface Force (CSF), Continuum Surface Stress (CSS) and also Meier's method, convert the surface tension force into a body force. Not only do they include the force in the interfacial cells but also in the neighboring cells. Thus they produce spurious currents. Also the pressure jump, due to the surface tension, is not calculated accurately in these methods. In this paper a more accurate method for the application of interface force in the computational modeling of free surfaces and interfaces which use PLIC-VOF methods is developed. This method is based on the evaluation of the surface tension force only in the interfacial cells and not the neighboring cells. Also the normal and the interface surface area needed for the calculation of the surface tension force is calculated more accurately. The present method is applied to a two-dimensional motionless drop of liquid and a bubble of gas as well as a non-circular two-dimensional drop, which oscillates due to the surface tension force, in an initially stagnant fluid with no gravity force. The results are compared with the results of the cases when CSF, CSS and Meier's methods are used. It is shown that the present method calculates pressure jump at the interface more accurately and produces less spurious currents comparing to CSS an CSF models. (author)

  20. About possibilities using of theoretical calculation methods in radioecology

    International Nuclear Information System (INIS)

    Demoukhamedova, S.D.; Aliev, D.I.; Alieva, I.N.

    2002-01-01

    Full text: Increasing the radiation level into environment is accompanied by accumulation of radioactive compounds into organism and/or their migration into biosphere. Radiotoxins are accumulated into irradiated plants and animals in result of violation of exchanging processes. The are play an important role at the pathogenesis of irradiation. To date, there is well known that even small quantity of the pesticides capable intensified the radiation effect. To understand the mechanism of radiation effect on physiologically active compounds and their complexes, the knowledge of such molecules three-dimensional organization and electron structure is essential. This work is devoted to study the pesticides of carbamate range, i.e. 'sevin' and its derivatives the physiological activity of which has been connected with cholinesterase degradation. Spatial organization and conformational possibilities of the pesticides has been studied using a method of the theoretical conformational analysis on the base of computational program worked out in laboratory of Molecular Biophysics at the Baku State University. Quantum-chemical methods CNDO/2, AM1 and PM3 and complex programs 'LEV' were used in studies of electronic structures of 'sevin' and number of its analogues. Charge distribution on the atoms, optimization of geometrical electrooptic parameters, as well as molecular electrostatic potentials, electron density and nuclear forces were calculated. Visual maps and surface of valence electron density distribution in the given plane and surface of electron-nuclear forces distribution projection were constructed. The geometrical and energetic characteristics, charges on the atoms of investigated pesticides, as well as the maps and relief of the valence electron density distribution on the atoms have been received. According to calculation results, the changing of charge distribution in naphthalene ring is observed. The conclusion was made that the carbonyl group is essential for

  1. Calculation-experimental method justifies the life of wagons

    Directory of Open Access Journals (Sweden)

    Валерія Сергіївна Воропай

    2015-11-01

    Full Text Available The article proposed a method to evaluate the technical state of tank wagons operating in chemical industry. An algorithm for evaluation the technical state of tank wagons was developed, that makes it possible on the basis of diagnosis and analysis of current condition to justify a further period of operation. The complex of works on testing the tanks and mathematical models for calculations of the design strength and reliability were proposed. The article is devoted to solving the problem of effective exploitation of the working fleet of tank wagons. Opportunities for further exploitation of cars, the complex of works on the assessment of their technical state and the calculation of the resources have been proposed in the article. Engineering research of the chemical industries park has reduced the shortage of the rolling stock for transportation of ammonia. The analysis of the chassis numerous faults and the main elements of tank wagons supporting structure after 20 years of exploitation was made. The algorithm of determining the residual life of the specialized tank wagons operating in an industrial plant has been proposed. The procedure for resource conservation of tank wagons carrying cargo under high pressure was first proposed. The improved procedure for identifying residual life proposed in the article has both theoretical and practical importance

  2. Acceleration and parallelization calculation of EFEN-SP_3 method

    International Nuclear Information System (INIS)

    Yang Wen; Zheng Youqi; Wu Hongchun; Cao Liangzhi; Li Yunzhao

    2013-01-01

    Due to the fact that the exponential function expansion nodal-SP_3 (EFEN-SP_3) method needs further improvement in computational efficiency to routinely carry out PWR whole core pin-by-pin calculation, the coarse mesh acceleration and spatial parallelization were investigated in this paper. The coarse mesh acceleration was built by considering discontinuity factor on each coarse mesh interface and preserving neutron balance within each coarse mesh in space, angle and energy. The spatial parallelization based on MPI was implemented by guaranteeing load balancing and minimizing communications cost to fully take advantage of the modern computing and storage abilities. Numerical results based on a commercial nuclear power reactor demonstrate an speedup ratio of about 40 for the coarse mesh acceleration and a parallel efficiency of higher than 60% with 40 CPUs for the spatial parallelization. With these two improvements, the EFEN code can complete a PWR whole core pin-by-pin calculation with 289 × 289 × 218 meshes and 4 energy groups within 100 s by using 48 CPUs (2.40 GHz frequency). (authors)

  3. Method of sections in analytical calculations of pneumatic tires

    Science.gov (United States)

    Tarasov, V. N.; Boyarkina, I. V.

    2018-01-01

    Analytical calculations in the pneumatic tire theory are more preferable in comparison with experimental methods. The method of section of a pneumatic tire shell allows to obtain equations of intensities of internal forces in carcass elements and bead rings. Analytical dependencies of intensity of distributed forces have been obtained in tire equator points, on side walls (poles) and pneumatic tire bead rings. Along with planes in the capacity of secant surfaces cylindrical surfaces are used for the first time together with secant planes. The tire capacity equation has been obtained using the method of section, by means of which a contact body is cut off from the tire carcass along the contact perimeter by the surface which is normal to the bearing surface. It has been established that the Laplace equation for the solution of tasks of this class of pneumatic tires contains two unknown values that requires the generation of additional equations. The developed computational schemes of pneumatic tire sections and new equations allow to accelerate the pneumatic tire structure improvement process during engineering.

  4. Calculation methods for advanced concept light water reactor lattices

    International Nuclear Information System (INIS)

    Carmona, S.

    1986-01-01

    In the last few years s several advanced concepts for fuel rod lattices have been studied. Improved fuel utilization is one of the major aims in the development of new fuel rod designs and lattice modifications. By these changes s better performance in fuel economics s fuel burnup and material endurance can be achieved in the frame of the well-known basic Light Water Reactor technology. Among the new concepts involved in these studies that have attracted serious attention are lattices consisting of arrays of annular rods duplex pellet rods or tight multicells. These new designs of fuel rods and lattices present several computational problems. The treatment of resonance shielded cross sections is a crucial point in the analyses of these advanced concepts . The purpose of this study was to assess adequate approximation methods for calculating as accurately as possible, resonance shielding for these new lattices. Although detailed and exact computational methods for the evaluation of the resonance shielding in these lattices are possible, they are quite inefficient when used in lattice codes. The computer time and memory required for this kind of computations are too large to be used in an acceptable routine manner. In order to over- come these limitations and to make the analyses possible with reasonable use of computer resources s approximation methods are necessary. Usual approximation methods, for the resonance energy regions used in routine lattice computer codes, can not adequately handle the evaluation of these new fuel rod lattices. The main contribution of the present work to advanced lattice concepts is the development of an equivalence principle for the calculation of resonance shielding in the annular fuel pellet zone of duplex pellets; the duplex pellet in this treatment consists of two fuel zones with the same absorber isotope in both regions. In the transition from a single duplex rod to an infinite array of this kind of fuel rods, the similarity of the

  5. An approximate method to calculate ionization of LTE and non-LTE plasma

    International Nuclear Information System (INIS)

    Zhang Jun; Gu Peijun

    1987-01-01

    When matter, especially high Z element, is heated to high temperature, it will be ionized many times. The degree of ionization has a strong effect on many plasma properties. So an approximate method to calculate the mean ionization degree is needed for solving many practical problems. An analytical expression which is convenient for the approximate numerical calculation is given by fitting it to the scaling law and numerical results of the ionization potential of Thomas-Fermi statistical model. In LTE case, the ionization degree of Au calculated by using the approximate method is in agreement with that of the average ion model. By extending the approximate method to non-LTE case, the ionization degree of Au is similarly calculated according to Corona model and Collision-Radiatoin model(C-R). The results of Corona model agree with the published data quite well, while the results of C-R approach those of Corona model as the density is reduced and approach those of LTE as the density is increased. Finally, all approximately calculated results of ionization degree of Au and the comparision of them are given in figures and tables

  6. Hamiltonian lattice field theory: Computer calculations using variational methods

    International Nuclear Information System (INIS)

    Zako, R.L.

    1991-01-01

    I develop a variational method for systematic numerical computation of physical quantities -- bound state energies and scattering amplitudes -- in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. I present an algorithm for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. I also show how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato's generalizations of Temple's formula. The algorithm could be adapted to systems such as atoms and molecules. I show how to compute Green's functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green's functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. I discuss the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, I do not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. I apply the method to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. I describe a computer implementation of the method and present numerical results for simple quantum mechanical systems

  7. Hamiltonian lattice field theory: Computer calculations using variational methods

    International Nuclear Information System (INIS)

    Zako, R.L.

    1991-01-01

    A variational method is developed for systematic numerical computation of physical quantities-bound state energies and scattering amplitudes-in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. An algorithm is presented for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. It is shown how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato's generalizations of Temple's formula. The algorithm could be adapted to systems such as atoms and molecules. It is shown how to compute Green's functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green's functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. The author discusses the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, the author does not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. The method is applied to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. The author describes a computer implementation of the method and present numerical results for simple quantum mechanical systems

  8. Development of methods for burn-up calculations for LWR's

    International Nuclear Information System (INIS)

    Jaschik, W.

    1978-01-01

    This method is based on all burn-up depending data, namely particle densities and neutron spectra, being available in a burn-up library. This one is created by means of a small number of cell burn-up calculations which can easily be carried out and in which the heterogeneous cell structure and self-shielding effects can explicitly be accounted for. Then the cluster burn-up is simulated by adequate correlation of the burn-up data. The advantage of this method is given by - an exact determination of the real spectrum distribution in the individual fuel element clusters; - an exact determination of the burn-up related spectrum variations for each fuel rod and for each burn-up value obtained; - accounting for heterogeneity of the fuel rod cells and the self-shielding in the fuel; high accuracy of the results of a comparably low effort and - simple handling by largely automating the process of computation. Programed realization was achieved by establishing the RSYST modules ABRAJA, MITHOM, and SIMABB and their implementation within the code system. (orig./HP) [de

  9. Methods for calculating the electrode position Jacobian for impedance imaging.

    Science.gov (United States)

    Boyle, A; Crabb, M G; Jehl, M; Lionheart, W R B; Adler, A

    2017-03-01

    Electrical impedance tomography (EIT) or electrical resistivity tomography (ERT) current and measure voltages at the boundary of a domain through electrodes. The movement or incorrect placement of electrodes may lead to modelling errors that result in significant reconstructed image artifacts. These errors may be accounted for by allowing for electrode position estimates in the model. Movement may be reconstructed through a first-order approximation, the electrode position Jacobian. A reconstruction that incorporates electrode position estimates and conductivity can significantly reduce image artifacts. Conversely, if electrode position is ignored it can be difficult to distinguish true conductivity changes from reconstruction artifacts which may increase the risk of a flawed interpretation. In this work, we aim to determine the fastest, most accurate approach for estimating the electrode position Jacobian. Four methods of calculating the electrode position Jacobian were evaluated on a homogeneous halfspace. Results show that Fréchet derivative and rank-one update methods are competitive in computational efficiency but achieve different solutions for certain values of contact impedance and mesh density.

  10. Calculation of neutron activation discriminating the chemical weapons underground using Monte Carlo methods

    International Nuclear Information System (INIS)

    Shen Chunxia; Qian Jianfu; Zhang Wenzhong

    2003-01-01

    This paper mainly calculate neutron activation discriminating the chemical weapons underground, and analyses the factors that soil influence discrimination, finally we conclude soil can not influence discrimination. (authors)

  11. A refined method for calculating equivalent effective stratospheric chlorine

    Science.gov (United States)

    Engel, Andreas; Bönisch, Harald; Ostermöller, Jennifer; Chipperfield, Martyn P.; Dhomse, Sandip; Jöckel, Patrick

    2018-01-01

    Chlorine and bromine atoms lead to catalytic depletion of ozone in the stratosphere. Therefore the use and production of ozone-depleting substances (ODSs) containing chlorine and bromine is regulated by the Montreal Protocol to protect the ozone layer. Equivalent effective stratospheric chlorine (EESC) has been adopted as an appropriate metric to describe the combined effects of chlorine and bromine released from halocarbons on stratospheric ozone. Here we revisit the concept of calculating EESC. We derive a refined formulation of EESC based on an advanced concept of ODS propagation into the stratosphere and reactive halogen release. A new transit time distribution is introduced in which the age spectrum for an inert tracer is weighted with the release function for inorganic halogen from the source gases. This distribution is termed the release time distribution. We show that a much better agreement with inorganic halogen loading from the chemistry transport model TOMCAT is achieved compared with using the current formulation. The refined formulation shows EESC levels in the year 1980 for the mid-latitude lower stratosphere, which are significantly lower than previously calculated. The year 1980 is commonly used as a benchmark to which EESC must return in order to reach significant progress towards halogen and ozone recovery. Assuming that - under otherwise unchanged conditions - the EESC value must return to the same level in order for ozone to fully recover, we show that it will take more than 10 years longer than estimated in this region of the stratosphere with the current method for calculation of EESC. We also present a range of sensitivity studies to investigate the effect of changes and uncertainties in the fractional release factors and in the assumptions on the shape of the release time distributions. We further discuss the value of EESC as a proxy for future evolution of inorganic halogen loading under changing atmospheric dynamics using simulations from

  12. Manual method for dose calculation in gynecologic brachytherapy; Metodo manual para o calculo de doses em braquiterapia ginecologica

    Energy Technology Data Exchange (ETDEWEB)

    Vianello, Elizabeth A.; Almeida, Carlos E. de [Instituto Nacional do Cancer, Rio de Janeiro, RJ (Brazil); Biaggio, Maria F. de [Universidade do Estado, Rio de Janeiro, RJ (Brazil)

    1998-09-01

    This paper describes a manual method for dose calculation in brachytherapy of gynecological tumors, which allows the calculation of the doses at any plane or point of clinical interest. This method uses basic principles of vectorial algebra and the simulating orthogonal films taken from the patient with the applicators and dummy sources in place. The results obtained with method were compared with the values calculated with the values calculated with the treatment planning system model Theraplan and the agreement was better than 5% in most cases. The critical points associated with the final accuracy of the proposed method is related to the quality of the image and the appropriate selection of the magnification factors. This method is strongly recommended to the radiation oncology centers where are no treatment planning systems available and the dose calculations are manually done. (author) 10 refs., 5 figs.

  13. Volume 1: Calculating potential to emit releases and doses for FEMP's and NOCs; FINAL

    International Nuclear Information System (INIS)

    HILL, J.S.

    1999-01-01

    The purpose of this document is to provide Hanford Site facilities a handbook for estimating potential emissions and the subsequent offsite doses. General guidelines and information are provided to assist personnel in estimating emissions for use with U.S. Department of Energy (DOE) facility effluent monitoring plans (FEMPs) and regulatory notices of construction (NOCs), per 40 Code of Federal Regulations (CFR) Part 61, Subpart H, and Washington Administrative Code (WAC) Chapter 246-247 requirements. This document replaces Unit Dose Calculation Methods and Summary of Facility Effluent Monitoring Plan Determinations (WHC-EP-0498). Meteorological data from 1983 through 1996, 13-year data set, was used to develop the unit dose factors provided by this document, with the exception of two meteorological stations. Meteorological stations 23 and 24, located at Gable Mountain and the 100-F Area, only have data from 1986 through 1996, 10-year data set. The scope of this document includes the following: Estimating emissions and resulting effective dose equivalents (EDE) to a facility's nearest offsite receptor (NOR) for use with NOCs under 40 CFR Part 61, Subpart H, requirements Estimating emissions and resulting EDEs to a facility's or emission unit's NOR for use with NOCs under the WAC Chapter 246-247 requirements Estimating emissions and resulting EDEs to a facility's or emission unit's NOR for use with FEMPs and FEMP determinations under DOE Orders 5400.1 and 5400.5 requirements

  14. Calculation of nuclear reaction parameters with the generator co-ordinate method and their interpretation

    International Nuclear Information System (INIS)

    Beck, R.; Mihailovic, M.V.; Poljsak, M.

    1980-05-01

    Collisions between complex nuclei are described variationally in terms of the GCM with the aim to provide an evidence that it is a manageable calculational procedure. The variational principle of Kohn and Kato is used to derive the expression for the K matrix. The space of scattering states is spanned entirely by antisymmetrized products of shell model wave functions describing separate clusters; the generator coordinate is the separation between the two shell model potentials. Scattering boundary conditions are enforced by solving an integral equation for the channel GC amplitude in each open channel separately. The main part of evaluation of collision parameters is performed by calculating double integrals of a form factor between channel GC amplitudes. A theorem about a property of the form factors is proved which allows reduction of the amount of work needed to calculate double integrals. The application of the method to the elastic 3 H to 4 He scattering has shown the feasibility of the calculation. It is shown how an analysis of calculated scattering parameters and corresponding scattering states in terms of quasibound states enables one to make a consistent comparison with experiment and to extract some knowledge of the reaction mechanism. Finally a comparative list of the calculational procedures of the GCM and RGM for reactions is made. (author)

  15. Method and program for complex calculation of heterogeneous reactor

    International Nuclear Information System (INIS)

    Kalashnikov, A.G.; Glebov, A.P.; Elovskaya, L.F.; Kuznetsova, L.I.

    1988-01-01

    An algorithm and the GITA program for complex one-dimensional calculation of a heterogeneous reactor which permits to conduct calculations for the reactor and its cell simultaneously using the same algorithm are described. Multigroup macrocross sections for reactor zones in the thermal energy range are determined according to the technique for calculating a cell with complicate structure and then the continuous multi group calculation of the reactor in the thermal energy range and in the range of neutron thermalization is made. The kinetic equation is solved using the Pi- and DSn- approximations [fr

  16. Estimation of subcriticality of TCA using 'indirect estimation method for calculation error'

    International Nuclear Information System (INIS)

    Naito, Yoshitaka; Yamamoto, Toshihiro; Arakawa, Takuya; Sakurai, Kiyoshi

    1996-01-01

    To estimate the subcriticality of neutron multiplication factor in a fissile system, 'Indirect Estimation Method for Calculation Error' is proposed. This method obtains the calculational error of neutron multiplication factor by correlating measured values with the corresponding calculated ones. This method was applied to the source multiplication and to the pulse neutron experiments conducted at TCA, and the calculation error of MCNP 4A was estimated. In the source multiplication method, the deviation of measured neutron count rate distributions from the calculated ones estimates the accuracy of calculated k eff . In the pulse neutron method, the calculation errors of prompt neutron decay constants give the accuracy of the calculated k eff . (author)

  17. Lambda-guided calculation method (LGC method) for xenon/CT CBF

    Energy Technology Data Exchange (ETDEWEB)

    Sase, Shigeru [Anzai Medical Co., Ltd., Tokyo (Japan); Honda, Mitsuru; Kushida, Tsuyoshi; Seiki, Yoshikatsu; Machida, Keiichi; Shibata, Iekado [Toho Univ., Tokyo (Japan). School of Medicine

    2001-12-01

    A quantitative CBF calculation method for xenon/CT was developed by logically estimating time-course change rate (rate constant) of arterial xenon concentration from that of end-tidal xenon concentration. A single factor ({gamma}) was introduced to correlate the end-tidal rate constant (Ke) with the arterial rate constant (Ka) in a simplified equation. This factor ({gamma}) is thought to reflect the diffusing capacity of the lung for xenon. When an appropriate value is given to {gamma}, it is possible to calculate the arterial rate constant (Calculated Ka) from Ke. To determine {gamma} for each xenon/CT CBF examination, a procedure was established which utilizes the characteristics of white matter lambda; lambda refers to xenon brain-blood partition coefficient. Xenon/CT studies were performed on four healthy volunteers. Hemispheric CBF values (47.0{+-}9.0 ml/100 g/min) with use of Calculated Ka were close to the reported normative values. For a 27-year-old healthy man, the rate constant for the common carotid artery was successfully measured and nearly equal to Calculated Ka. The authors conclude the method proposed in this work, lambda-guided calculation method, could make xenon/CT CBF substantially reliable and quantitative by effective use of end-tidal xenon. (author)

  18. Lambda-guided calculation method (LGC method) for xenon/CT CBF

    International Nuclear Information System (INIS)

    Sase, Shigeru; Honda, Mitsuru; Kushida, Tsuyoshi; Seiki, Yoshikatsu; Machida, Keiichi; Shibata, Iekado

    2001-01-01

    A quantitative CBF calculation method for xenon/CT was developed by logically estimating time-course change rate (rate constant) of arterial xenon concentration from that of end-tidal xenon concentration. A single factor (γ) was introduced to correlate the end-tidal rate constant (Ke) with the arterial rate constant (Ka) in a simplified equation. This factor (γ) is thought to reflect the diffusing capacity of the lung for xenon. When an appropriate value is given to γ, it is possible to calculate the arterial rate constant (Calculated Ka) from Ke. To determine γ for each xenon/CT CBF examination, a procedure was established which utilizes the characteristics of white matter lambda; lambda refers to xenon brain-blood partition coefficient. Xenon/CT studies were performed on four healthy volunteers. Hemispheric CBF values (47.0±9.0 ml/100 g/min) with use of Calculated Ka were close to the reported normative values. For a 27-year-old healthy man, the rate constant for the common carotid artery was successfully measured and nearly equal to Calculated Ka. The authors conclude the method proposed in this work, lambda-guided calculation method, could make xenon/CT CBF substantially reliable and quantitative by effective use of end-tidal xenon. (author)

  19. Comparison of Monte Carlo method and deterministic method for neutron transport calculation

    International Nuclear Information System (INIS)

    Mori, Takamasa; Nakagawa, Masayuki

    1987-01-01

    The report outlines major features of the Monte Carlo method by citing various applications of the method and techniques used for Monte Carlo codes. Major areas of its application include analysis of measurements on fast critical assemblies, nuclear fusion reactor neutronics analysis, criticality safety analysis, evaluation by VIM code, and calculation for shielding. Major techniques used for Monte Carlo codes include the random walk method, geometric expression method (combinatorial geometry, 1, 2, 4-th degree surface and lattice geometry), nuclear data expression, evaluation method (track length, collision, analog (absorption), surface crossing, point), and dispersion reduction (Russian roulette, splitting, exponential transform, importance sampling, corrected sampling). Major features of the Monte Carlo method are as follows: 1) neutron source distribution and systems of complex geometry can be simulated accurately, 2) physical quantities such as neutron flux in a place, on a surface or at a point can be evaluated, and 3) calculation requires less time. (Nogami, K.)

  20. A comparison study of size-specific dose estimate calculation methods

    Energy Technology Data Exchange (ETDEWEB)

    Parikh, Roshni A. [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); University of Michigan Health System, Department of Radiology, Ann Arbor, MI (United States); Wien, Michael A.; Jordan, David W.; Ciancibello, Leslie; Berlin, Sheila C. [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); Novak, Ronald D. [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); Rebecca D. Considine Research Institute, Children' s Hospital Medical Center of Akron, Center for Mitochondrial Medicine Research, Akron, OH (United States); Klahr, Paul [CT Clinical Science, Philips Healthcare, Highland Heights, OH (United States); Soriano, Stephanie [Rainbow Babies and Children' s Hospital, University Hospitals Cleveland Medical Center, Case Western Reserve University School of Medicine, Department of Radiology, Cleveland, OH (United States); University of Washington, Department of Radiology, Seattle, WA (United States)

    2018-01-15

    The size-specific dose estimate (SSDE) has emerged as an improved metric for use by medical physicists and radiologists for estimating individual patient dose. Several methods of calculating SSDE have been described, ranging from patient thickness or attenuation-based (automated and manual) measurements to weight-based techniques. To compare the accuracy of thickness vs. weight measurement of body size to allow for the calculation of the size-specific dose estimate (SSDE) in pediatric body CT. We retrospectively identified 109 pediatric body CT examinations for SSDE calculation. We examined two automated methods measuring a series of level-specific diameters of the patient's body: method A used the effective diameter and method B used the water-equivalent diameter. Two manual methods measured patient diameter at two predetermined levels: the superior endplate of L2, where body width is typically most thin, and the superior femoral head or iliac crest (for scans that did not include the pelvis), where body width is typically most thick; method C averaged lateral measurements at these two levels from the CT projection scan, and method D averaged lateral and anteroposterior measurements at the same two levels from the axial CT images. Finally, we used body weight to characterize patient size, method E, and compared this with the various other measurement methods. Methods were compared across the entire population as well as by subgroup based on body width. Concordance correlation (ρ{sub c}) between each of the SSDE calculation methods (methods A-E) was greater than 0.92 across the entire population, although the range was wider when analyzed by subgroup (0.42-0.99). When we compared each SSDE measurement method with CTDI{sub vol,} there was poor correlation, ρ{sub c}<0.77, with percentage differences between 20.8% and 51.0%. Automated computer algorithms are accurate and efficient in the calculation of SSDE. Manual methods based on patient thickness provide

  1. Research program in reactor core diagnostics with neutron noise methods: Stage 3. Final report

    International Nuclear Information System (INIS)

    Pazsit, I.; Garis, N.S.; Karlsson, J.; Racz, A.

    1997-09-01

    Stage 3 of the program has been executed 96-04-12. The long term goal is to develop noise methods for identification and localization of perturbations in reactor cores. The main parts of the program consist of modelling the noise source, calculation of the space- and frequency dependent transfer function, calculation of the neutron noise via a convolution of the transfer function of the system and the noise source, i.e. the perturbation, and finally finding an inversion or unfolding procedure to determine noise source parameters from the neutron noise. Most previous work is based on very simple (analytical) reactor models for the calculation of the transfer function as well as analytical unfolding methods. The purpose of this project is to calculate the transfer function in a more realistic model as well as elaborating powerful inversion methods that do not require analytical transfer functions. The work in stage 3 is described under the following headlines: Further investigation of simplified models for the calculation of the neutron noise; Further investigation of methods based on neural networks; Further investigation of methods for detecting the vibrations and impacting of detectors; Application of static codes for determination of the neutron noise using the adiabatic approximation

  2. Reactor calculation in coarse mesh by finite element method applied to matrix response method

    International Nuclear Information System (INIS)

    Nakata, H.

    1982-01-01

    The finite element method is applied to the solution of the modified formulation of the matrix-response method aiming to do reactor calculations in coarse mesh. Good results are obtained with a short running time. The method is applicable to problems where the heterogeneity is predominant and to problems of evolution in coarse meshes where the burnup is variable in one same coarse mesh, making the cross section vary spatially with the evolution. (E.G.) [pt

  3. A method for bubble volume calculating in vertical two-phase flow

    International Nuclear Information System (INIS)

    Wang, H Y; Dong, F

    2009-01-01

    The movement of bubble is a basic subject in gas-liquid two-phase flow research. A method for calculating bubble volume which is one of the most important characters in bubble motion research was proposed. A suit of visualized experimental device was designed and set up. Single bubble rising in stagnant liquid in a rectangular tank was studied using the high-speed video system. Bubbles generated by four orifice with different diameter (1mm, 2mm, 3mm, 4mm) were recorded respectively. Sequences of recorded high-speed images were processed by digital image processing method, such as image noise remove, binary image transform, bubble filling, and so on. then, Several parameters could be obtained from the processed image. Bubble area, equivalent diameter, bubble velocity, bubble acceleration are all indispensable in bubble volume calculating. In order to get the force balance equation, forces that work on bubble along vertical direction, including drag force, virtual mass force, buoyancy, gravity and liquid thrust, were analyzed. Finally, the bubble volume formula could be derived from the force balance equation and bubble parameters. Examples were given to shown the computing process and results. Comparison of the bubble volume calculated by geomettic method and the present method have shown the superiority of the proposed method in this paper.

  4. Accurate methods for calculating atomic processes in high temperature plasmas

    International Nuclear Information System (INIS)

    Keady, J.J.; Abdallah, J.A. Jr.; Clark, R.E.H.

    1992-01-01

    A technique for computing monochromatic X-ray absorption is described and compared to experimental data. Calculations of power loss from carbon plasmas with comprehensive new datasets confirm that the direct inclusion of metastable states can noticeably decrease the calculated power loss

  5. Structural reliability calculation method based on the dual neural network and direct integration method.

    Science.gov (United States)

    Li, Haibin; He, Yun; Nie, Xiaobo

    2018-01-01

    Structural reliability analysis under uncertainty is paid wide attention by engineers and scholars due to reflecting the structural characteristics and the bearing actual situation. The direct integration method, started from the definition of reliability theory, is easy to be understood, but there are still mathematics difficulties in the calculation of multiple integrals. Therefore, a dual neural network method is proposed for calculating multiple integrals in this paper. Dual neural network consists of two neural networks. The neural network A is used to learn the integrand function, and the neural network B is used to simulate the original function. According to the derivative relationships between the network output and the network input, the neural network B is derived from the neural network A. On this basis, the performance function of normalization is employed in the proposed method to overcome the difficulty of multiple integrations and to improve the accuracy for reliability calculations. The comparisons between the proposed method and Monte Carlo simulation method, Hasofer-Lind method, the mean value first-order second moment method have demonstrated that the proposed method is an efficient and accurate reliability method for structural reliability problems.

  6. Final Report: Symposium on Adaptive Methods for Partial Differential Equations

    Energy Technology Data Exchange (ETDEWEB)

    Pernice, M.; Johnson, C.R.; Smith, P.J.; Fogelson, A.

    1998-12-10

    OAK-B135 Final Report: Symposium on Adaptive Methods for Partial Differential Equations. Complex physical phenomena often include features that span a wide range of spatial and temporal scales. Accurate simulation of such phenomena can be difficult to obtain, and computations that are under-resolved can even exhibit spurious features. While it is possible to resolve small scale features by increasing the number of grid points, global grid refinement can quickly lead to problems that are intractable, even on the largest available computing facilities. These constraints are particularly severe for three dimensional problems that involve complex physics. One way to achieve the needed resolution is to refine the computational mesh locally, in only those regions where enhanced resolution is required. Adaptive solution methods concentrate computational effort in regions where it is most needed. These methods have been successfully applied to a wide variety of problems in computational science and engineering. Adaptive methods can be difficult to implement, prompting the development of tools and environments to facilitate their use. To ensure that the results of their efforts are useful, algorithm and tool developers must maintain close communication with application specialists. Conversely it remains difficult for application specialists who are unfamiliar with the methods to evaluate the trade-offs between the benefits of enhanced local resolution and the effort needed to implement an adaptive solution method.

  7. Comparison of Two-Block Decomposition Method and Chebyshev Rational Approximation Method for Depletion Calculation

    International Nuclear Information System (INIS)

    Lee, Yoon Hee; Cho, Nam Zin

    2016-01-01

    The code gives inaccurate results of nuclides for evaluation of source term analysis, e.g., Sr- 90, Ba-137m, Cs-137, etc. A Krylov Subspace method was suggested by Yamamoto et al. The method is based on the projection of solution space of Bateman equation to a lower dimension of Krylov subspace. It showed good accuracy in the detailed burnup chain calculation if dimension of the Krylov subspace is high enough. In this paper, we will compare the two methods in terms of accuracy and computing time. In this paper, two-block decomposition (TBD) method and Chebyshev rational approximation method (CRAM) are compared in the depletion calculations. In the two-block decomposition method, according to the magnitude of effective decay constant, the system of Bateman equation is decomposed into short- and longlived blocks. The short-lived block is calculated by the general Bateman solution and the importance concept. Matrix exponential with smaller norm is used in the long-lived block. In the Chebyshev rational approximation, there is no decomposition of the Bateman equation system, and the accuracy of the calculation is determined by the order of expansion in the partial fraction decomposition of the rational form. The coefficients in the partial fraction decomposition are determined by a Remez-type algorithm.

  8. Comparison of Two-Block Decomposition Method and Chebyshev Rational Approximation Method for Depletion Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yoon Hee; Cho, Nam Zin [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The code gives inaccurate results of nuclides for evaluation of source term analysis, e.g., Sr- 90, Ba-137m, Cs-137, etc. A Krylov Subspace method was suggested by Yamamoto et al. The method is based on the projection of solution space of Bateman equation to a lower dimension of Krylov subspace. It showed good accuracy in the detailed burnup chain calculation if dimension of the Krylov subspace is high enough. In this paper, we will compare the two methods in terms of accuracy and computing time. In this paper, two-block decomposition (TBD) method and Chebyshev rational approximation method (CRAM) are compared in the depletion calculations. In the two-block decomposition method, according to the magnitude of effective decay constant, the system of Bateman equation is decomposed into short- and longlived blocks. The short-lived block is calculated by the general Bateman solution and the importance concept. Matrix exponential with smaller norm is used in the long-lived block. In the Chebyshev rational approximation, there is no decomposition of the Bateman equation system, and the accuracy of the calculation is determined by the order of expansion in the partial fraction decomposition of the rational form. The coefficients in the partial fraction decomposition are determined by a Remez-type algorithm.

  9. Three-phase short circuit calculation method based on pre-computed surface for doubly fed induction generator

    Science.gov (United States)

    Ma, J.; Liu, Q.

    2018-02-01

    This paper presents an improved short circuit calculation method, based on pre-computed surface to determine the short circuit current of a distribution system with multiple doubly fed induction generators (DFIGs). The short circuit current, injected into power grid by DFIG, is determined by low voltage ride through (LVRT) control and protection under grid fault. However, the existing methods are difficult to calculate the short circuit current of DFIG in engineering practice due to its complexity. A short circuit calculation method, based on pre-computed surface, was proposed by developing the surface of short circuit current changing with the calculating impedance and the open circuit voltage. And the short circuit currents were derived by taking into account the rotor excitation and crowbar activation time. Finally, the pre-computed surfaces of short circuit current at different time were established, and the procedure of DFIG short circuit calculation considering its LVRT was designed. The correctness of proposed method was verified by simulation.

  10. Calculation device for amount of heavy element nuclide in reactor fuels and calculation method therefor

    International Nuclear Information System (INIS)

    Naka, Takafumi; Yamamoto, Munenari.

    1995-01-01

    When there are two or more origins of deuterium nuclides in reactor fuels, there are disposed a memory device for an amount of deuterium nuclides for every origin in a noted fuel segment at a certain time point, a device for calculating the amount of nuclides for every origin and current neutron fluxes in the noted fuel segment, and a device for separating and then displaying the amount of deuterium nuclides for every origin. Equations for combustion are dissolved for every origin of the deuterium nuclides based on the amount of the deuterium nuclides for every origin and neutron fluxes, to calculate the current amount of deuterium nuclides for every origin. The amount of deuterium nuclides originated from uranium is calculated ignoring α-decay of curium, while the amount of deuterium nuclides originated from plutonium is calculated ignoring the generation of plutonium formed from neptunium. Deuterium nuclides can be measured and controlled accurately for every origin of the reactor fuels. Even when nuclear fuel materials have two or more nationalities, the measurement and control thereof can be conducted for every country. (N.H.)

  11. Advances in supercell calculation methods and comparison with measurements

    Energy Technology Data Exchange (ETDEWEB)

    Arsenault, B [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada); Baril, R; Hotte, G [Hydro-Quebec, Central Nucleaire Gentilly, Montreal, Quebec (Canada)

    1996-07-01

    In the last few years, modelling techniques have been developed in new supercell computer codes. These techniques have been used to model the CANDU reactivity devices. One technique is based on one- and two-dimensional transport calculations with the WIMS-AECL lattice code followed by super homogenization and three-dimensional flux calculations in a modified version of the MULTICELL code. The second technique is based on two- and three-dimensional transport calculations in DRAGON. The code calculates the lattice properties by solving the transport equation in a two-dimensional geometry followed by supercell calculations in three dimensions. These two calculation schemes have been used to calculate the incremental macroscopic properties of CANDU reactivity devices. The supercell size has also been modified to define incremental properties over a larger region. The results show improved agreement between the reactivity worth of zone controllers and adjusters. However, at the same time the agreement between measured and simulated flux distributions deteriorated somewhat. (author)

  12. Field calculations. Part I: Choice of variables and methods

    International Nuclear Information System (INIS)

    Turner, L.R.

    1981-01-01

    Magnetostatic calculations can involve (in order of increasing complexity) conductors only, material with constant or infinite permeability, or material with variable permeability. We consider here only the most general case, calculations involving ferritic material with variable permeability. Variables suitable for magnetostatic calculations are the magnetic field, the magnetic vector potential, and the magnetic scalar potential. For two-dimensional calculations the potentials, which each have only one component, have advantages over the field, which has two components. Because it is a single-valued variable, the vector potential is perhaps the best variable for two-dimensional calculations. In three dimensions, both the field and the vector potential have three components; the scalar potential, with only one component,provides a much smaller system of equations to be solved. However the scalar potential is not single-valued. To circumvent this problem, a calculation with two scalar potentials can be performed. The scalar potential whose source is the conductors can be calculated directly by the Biot-Savart law, and the scalar potential whose source is the magnetized material is single valued. However in some situations, the fields from the two potentials nearly cancel; and the numerical accuracy is lost. The 3-D magnetostatic program TOSCA employs a single total scalar potential; the program GFUN uses the magnetic field as its variable

  13. Assessment of uncertainty in full core reactor physics calculations using statistical methods

    International Nuclear Information System (INIS)

    McEwan, C.

    2012-01-01

    The best estimate method of safety analysis involves choosing a realistic set of input parameters for a proposed safety case and evaluating the uncertainty in the results. Determining the uncertainty in code outputs remains a challenge and is the subject of a benchmarking exercise proposed by the Organization for Economic Cooperation and Development. The work proposed in this paper will contribute to this benchmark by assessing the uncertainty in a depletion calculation of the final nuclide concentrations for an experiment performed in the Fukushima-2 reactor. This will be done using lattice transport code DRAGON and a tool known as DINOSAUR. (author)

  14. Assessment of uncertainty in full core reactor physics calculations using statistical methods

    Energy Technology Data Exchange (ETDEWEB)

    McEwan, C., E-mail: mcewac2@mcmaster.ca [McMaster Univ., Hamilton, Ontario (Canada)

    2012-07-01

    The best estimate method of safety analysis involves choosing a realistic set of input parameters for a proposed safety case and evaluating the uncertainty in the results. Determining the uncertainty in code outputs remains a challenge and is the subject of a benchmarking exercise proposed by the Organization for Economic Cooperation and Development. The work proposed in this paper will contribute to this benchmark by assessing the uncertainty in a depletion calculation of the final nuclide concentrations for an experiment performed in the Fukushima-2 reactor. This will be done using lattice transport code DRAGON and a tool known as DINOSAUR. (author)

  15. Current evaluation of dose rate calculation - analytical method

    International Nuclear Information System (INIS)

    Tello, Marcos; Vilhena, Marco Tulio

    1996-01-01

    The accuracy of the dose calculations based on pencil beam formulas such as Fokker-Plank equations and Fermi equations for charged particle transport are studied and a methodology to solve the Boltzmann transport equation is suggested

  16. A calculation method of cracking moment for the high strength ...

    Indian Academy of Sciences (India)

    mal stress and crack width for the tensional behaviour of concrete and has been proposed by ... stresses. To calculate concrete stress in a cross section of high strength concrete beams, failure strain is ..... American Concrete. Institute, Detroit.

  17. Method of the characteristics for calculation of VVER without homogenization

    Energy Technology Data Exchange (ETDEWEB)

    Suslov, I.R.; Komlev, O.G.; Novikova, N.N.; Zemskov, E.A.; Tormyshev, I.V.; Melnikov, K.G.; Sidorov, E.B. [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    2005-07-01

    The first stage of the development of characteristics code MCCG3D for calculation of the VVER-type reactor without homogenization is presented. The parallel version of the code for MPI was developed and tested on cluster PC with LINUX-OS. Further development of the MCCG3D code for design-level calculations with full-scale space-distributed feedbacks is discussed. For validation of the MCCG3D code we use the critical assembly VENUS-2. The geometrical models with and without homogenization have been used. With both models the MCCG3D results agree well with the experimental power distribution and with results generated by the other codes, but model without homogenization provides better results. The perturbation theory for MCCG3D code is developed and implemented in the module KEFSFGG. The calculations with KEFSFGG are in good agreement with direct calculations. (authors)

  18. Whole core calculations of power reactors by Monte Carlo method

    International Nuclear Information System (INIS)

    Nakagawa, Masayuki; Mori, Takamasa

    1993-01-01

    Whole core calculations have been performed for a commercial size PWR and a prototype LMFBR by using vectorized Monte Carlo codes. Geometries of cores were precisely represented in a pin by pin model. The calculated parameters were k eff , control rod worth, power distribution and so on. Both multigroup and continuous energy models were used and the accuracy of multigroup approximation was evaluated through the comparison of both results. One million neutron histories were tracked to considerably reduce variances. It was demonstrated that the high speed vectorized codes could calculate k eff , assembly power and some reactivity worths within practical computation time. For pin power and small reactivity worth calculations, the order of 10 million histories would be necessary. Required number of histories to achieve target design accuracy were estimated for those neutronic parameters. (orig.)

  19. A method for calculating active feedback system to provide vertical

    Indian Academy of Sciences (India)

    The active feedback system is applied to control slow motions of plasma. The objective of the ... The other problem is connected with the control of plasma vertical position with active feedback system. Calculation of ... Current Issue Volume 90 ...

  20. An approximate method for calculating the deformation of rotating nuclei

    International Nuclear Information System (INIS)

    Lind, P.

    1988-01-01

    The author presents as a collective model where the potential surface at spin I=0 is calculated in the Nilsson-Strutinsky model, an analytical expression for the moment of inertia is used which depends on the deformation and the pairing gaps for protons and neutrons, and the energy is minimized with respect to these gaps. Calculations in this model are performed for 16 Oyb. (HSI)

  1. The unit cost factors and calculation methods for decommissioning - Cost estimation of nuclear research facilities

    International Nuclear Information System (INIS)

    Kwan-Seong Jeong; Dong-Gyu Lee; Chong-Hun Jung; Kune-Woo Lee

    2007-01-01

    Available in abstract form only. Full text of publication follows: The uncertainties of decommissioning costs increase high due to several conditions. Decommissioning cost estimation depends on the complexity of nuclear installations, its site-specific physical and radiological inventories. Therefore, the decommissioning costs of nuclear research facilities must be estimated in accordance with the detailed sub-tasks and resources by the tasks of decommissioning activities. By selecting the classified activities and resources, costs are calculated by the items and then the total costs of all decommissioning activities are reshuffled to match with its usage and objectives. And the decommissioning cost of nuclear research facilities is calculated by applying a unit cost factor method on which classification of decommissioning works fitted with the features and specifications of decommissioning objects and establishment of composition factors are based. Decommissioning costs of nuclear research facilities are composed of labor cost, equipment and materials cost. Of these three categorical costs, the calculation of labor costs are very important because decommissioning activities mainly depend on labor force. Labor costs in decommissioning activities are calculated on the basis of working time consumed in decommissioning objects and works. The working times are figured out of unit cost factors and work difficulty factors. Finally, labor costs are figured out by using these factors as parameters of calculation. The accuracy of decommissioning cost estimation results is much higher compared to the real decommissioning works. (authors)

  2. Thermal-hydraulic calculation methods for transients and accidents of the reactor cooling system under special consideration of multi-dimensional flows (ATHLET, FLUBOX, CFX). Final report; Thermohydraulische Rechenmethoden zu Transienten und Stoerfaellen im Reaktorkuehlkreislauf unter besonderer Beruecksichtigung mehrdimensionaler Stroemungen (ATHLET, FLUBOX, CFX). Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Glaeser, H.; Graf, U.; Herb, J.; and others

    2012-02-15

    The project RS1184 „Thermal-hydraulic Calculation Methods for Transients and Accidents of the Reactor Cooling System Under Special Consideration of Multi-Dimensional Flows (ATHLET, FLUBOX, CFX)'' consists of four work packages: 1. Further development of the computer code ATHLET 2. Termination of FLUBOX development and development of an ATHLET-internal 3D module 3. Coupling of ATHLET and CFD code ANSYS CFX as well as CFX model development to simulate three-dimensional flows in the reactor coolant system 4. Prediction capability of computer code ATHLET. One of the superior objectives of the project is to improve the prediction capability of the thermal-hydraulic system code ATHLET, including the simulation of multi-dimensional flow in the reactor vessel. The constitutive equations in ATHLET, especially the momentum equations in ATHLET, are written in one-dimensional form. It was planned to develop the 2D/3D module FLUBOX further and couple it with ATHLET. Due to reasons given in chapter 3, the FLUBOX development was terminated. Instead, the decision was made to develop a fast running internal ATHLET-module. The 2D/3D equations for ATHLET have been derived and were implemented. That strategy allows using all ATHLET models and the ATHLET code structure. An additional advantage is that different numerical schemes of different codes, and consequently a loss of efficiency, will be avoided. A second possibility is the coupling of ATHLET with the CFD code ANSYS CFX. Such a coupled code system will be used in those cases when a part of the simulation area is needed to be calculated with high resolution. Such a detailed modelling cannot be provided by ATHLET-3D. A complete representation of the cooling system by a CFD code cannot be performed due to calculation time. In order to calculate the complete system behavior still with ATHLET, that part to be investigated in more detail, will be replaced by a CFX model. Several new models and improvements of existing

  3. Failure Probability Calculation Method Using Kriging Metamodel-based Importance Sampling Method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seunggyu [Korea Aerospace Research Institue, Daejeon (Korea, Republic of); Kim, Jae Hoon [Chungnam Nat’l Univ., Daejeon (Korea, Republic of)

    2017-05-15

    The kernel density was determined based on sampling points obtained in a Markov chain simulation and was assumed to be an important sampling function. A Kriging metamodel was constructed in more detail in the vicinity of a limit state. The failure probability was calculated based on importance sampling, which was performed for the Kriging metamodel. A pre-existing method was modified to obtain more sampling points for a kernel density in the vicinity of a limit state. A stable numerical method was proposed to find a parameter of the kernel density. To assess the completeness of the Kriging metamodel, the possibility of changes in the calculated failure probability due to the uncertainty of the Kriging metamodel was calculated.

  4. Calculation of the Local Free Energy Landscape in the Restricted Region by the Modified Tomographic Method.

    Science.gov (United States)

    Chen, Changjun

    2016-03-31

    The free energy landscape is the most important information in the study of the reaction mechanisms of the molecules. However, it is difficult to calculate. In a large collective variable space, a molecule must take a long time to obtain the sufficient sampling during the simulation. To save the calculation quantity, decreasing the sampling region and constructing the local free energy landscape is required in practice. However, the restricted region in the collective variable space may have an irregular shape. Simply restricting one or more collective variables of the molecule cannot satisfy the requirement. In this paper, we propose a modified tomographic method to perform the simulation. First, it divides the restricted region by some hyperplanes and connects the centers of hyperplanes together by a curve. Second, it forces the molecule to sample on the curve and the hyperplanes in the simulation and calculates the free energy data on them. Finally, all the free energy data are combined together to form the local free energy landscape. Without consideration of the area outside the restricted region, this free energy calculation can be more efficient. By this method, one can further optimize the path quickly in the collective variable space.

  5. Calculating energy and labor impacts of capital readjustments due to changes in personal consumption. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pleszkun, A.R.

    1979-05-01

    Previous work on the energy and labor impacts of energy-consumption policies has included the effect of respending of money saved, but not the capital implications of this respending. Here the capital effects are fully accounted for, and turn out to be negligible for a specified conservation scenario and a specified capital expansion model (..delta..C = kC). The robustness of this conclusion is discussed. The implication is that inclusion of only the respending effect is adequate for calculating energy and labor impacts and provides an accuracy to within +- 1% of the total impacts. Operationally, this result obviates the requirement for detailed and expensive calculations.

  6. Reliable method for fission source convergence of Monte Carlo criticality calculation with Wielandt's method

    International Nuclear Information System (INIS)

    Yamamoto, Toshihiro; Miyoshi, Yoshinori

    2004-01-01

    A new algorithm of Monte Carlo criticality calculations for implementing Wielandt's method, which is one of acceleration techniques for deterministic source iteration methods, is developed, and the algorithm can be successfully implemented into MCNP code. In this algorithm, part of fission neutrons emitted during random walk processes are tracked within the current cycle, and thus a fission source distribution used in the next cycle spread more widely. Applying this method intensifies a neutron interaction effect even in a loosely-coupled array where conventional Monte Carlo criticality methods have difficulties, and a converged fission source distribution can be obtained with fewer cycles. Computing time spent for one cycle, however, increases because of tracking fission neutrons within the current cycle, which eventually results in an increase of total computing time up to convergence. In addition, statistical fluctuations of a fission source distribution in a cycle are worsened by applying Wielandt's method to Monte Carlo criticality calculations. However, since a fission source convergence is attained with fewer source iterations, a reliable determination of convergence can easily be made even in a system with a slow convergence. This acceleration method is expected to contribute to prevention of incorrect Monte Carlo criticality calculations. (author)

  7. Method of treating final products from flue gas desulfurization

    International Nuclear Information System (INIS)

    Bloss, W.; Mohn, U.

    1984-01-01

    A method of treating final products from a flue gas desulfurization. The flue gas desulfurization is carried out by the absorption of sulfur oxide in a spray dryer with a suspension which contains lime, or in a reactor with a dry, fine-grained, absorbent which contains lime. Prior to desulfurization, the fly ash carried along by the flue gas which is to be desulfurized is separated entirely, partially, or not at all from the flue gas, and the final products from the flue gas desulfurization, prior to any further treatment thereof, amount to 1-99% by weight, preferably 1-70% by weight, of fly ash, and 1-99% by weight, preferably 30-99% by weight, of the sum of the desulfurization products, preferably calcium sulfite hemihydrate, and/or calcium sulfite, and/or calcium sulfate dyhydrate, and/or calcium sulfate hemihydrate, and/or calcium sulfate, as well as residue of the absorbent. The reduction of the amount of calcium sulfite is implemented by a dry oxidation with air

  8. Efficient Method for Calculating the Composite Stiffness of Parabolic Leaf Springs with Variable Stiffness for Vehicle Rear Suspension

    Directory of Open Access Journals (Sweden)

    Wen-ku Shi

    2016-01-01

    Full Text Available The composite stiffness of parabolic leaf springs with variable stiffness is difficult to calculate using traditional integral equations. Numerical integration or FEA may be used but will require computer-aided software and long calculation times. An efficient method for calculating the composite stiffness of parabolic leaf springs with variable stiffness is developed and evaluated to reduce the complexity of calculation and shorten the calculation time. A simplified model for double-leaf springs with variable stiffness is built, and a composite stiffness calculation method for the model is derived using displacement superposition and material deformation continuity. The proposed method can be applied on triple-leaf and multileaf springs. The accuracy of the calculation method is verified by the rig test and FEA analysis. Finally, several parameters that should be considered during the design process of springs are discussed. The rig test and FEA analytical results indicate that the calculated results are acceptable. The proposed method can provide guidance for the design and production of parabolic leaf springs with variable stiffness. The composite stiffness of the leaf spring can be calculated quickly and accurately when the basic parameters of the leaf spring are known.

  9. Output calculation of electron therapy at extended SSD using an improved LBR method

    Energy Technology Data Exchange (ETDEWEB)

    Alkhatib, Hassaan A.; Gebreamlak, Wondesen T., E-mail: wondtassew@gmail.com; Wright, Ben W.; Neglia, William J. [South Carolina Oncology Associates, Columbia, South Carolina 29210 (United States); Tedeschi, David J. [Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208 (United States); Mihailidis, Dimitris [CAMC Cancer Center and Alliance Oncology, Charleston, West Virginia 25304 (United States); Sobash, Philip T. [The Medical University of South Carolina, Charleston, South Carolina 29425 (United States); Fontenot, Jonas D. [Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, Louisiana 70809 (United States)

    2015-02-15

    Purpose: To calculate the output factor (OPF) of any irregularly shaped electron beam at extended SSD. Methods: Circular cutouts were prepared from 2.0 cm diameter to the maximum possible size for 15 × 15 applicator cone. In addition, two irregular cutouts were prepared. For each cutout, percentage depth dose (PDD) at the standard SSD and doses at different SSD values were measured using 6, 9, 12, and 16 MeV electron beam energies on a Varian 2100C LINAC and the distance at which the central axis electron fluence becomes independent of cutout size was determined. The measurements were repeated with an ELEKTA Synergy LINAC using 14 × 14 applicator cone and electron beam energies of 6, 9, 12, and 15 MeV. The PDD measurements were performed using a scanning system and two diodes—one for the signal and the other a stationary reference outside the tank. The doses of the circular cutouts at different SSDs were measured using PTW 0.125 cm{sup 3} Semiflex ion-chamber and EDR2 films. The electron fluence was measured using EDR2 films. Results: For each circular cutout, the lateral buildup ratio (LBR) was calculated from the measured PDD curve using the open applicator cone as the reference field. The effective SSD (SSD{sub eff}) of each circular cutout was calculated from the measured doses at different SSD values. Using the LBR value and the radius of the circular cutout, the corresponding lateral spread parameter [σ{sub R}(z)] was calculated. Taking the cutout size dependence of σ{sub R}(z) into account, the PDD curves of the irregularly shaped cutouts at the standard SSD were calculated. Using the calculated PDD curve of the irregularly shaped cutout along with the LBR and SSD{sub eff} values of the circular cutouts, the output factor of the irregularly shaped cutout at extended SSD was calculated. Finally, both the calculated PDD curves and output factor values were compared with the measured values. Conclusions: The improved LBR method has been generalized to

  10. Measurement, calculation and evaluation of photon production data. Final report of a coordinated research project

    International Nuclear Information System (INIS)

    Oblozinsky, P.; Dietrich, F.S.; Mengoni, A.

    1999-12-01

    The report summarizes results of the Coordinated Research Project (CRP) devoted to photon preduction in neutron-induced reactions. The report presents 25 original contributions that reflect accomplishments achieved in measurement, calculation and evaluation of photon production under the project in 1994-1997. Major results are highlighted and a list of the CRP publications is given. (author)

  11. A method to calculate spatial xenon oscillations in PWR reactors

    International Nuclear Information System (INIS)

    Ronig, H.

    1976-01-01

    The new digital computer programme SEXI for the calculation of spatial Xe oscillations is described. A series expansion of the flux density and the particle densities following the geometrical eigenfunctions of a homogeneous block reactor is chosen as an approach to the solution of the system of differential equations describing this feedback process between neutron flux density and Xe particle density. To calculate the neutron flux density, the time-dependent form of the diffusion equation is used instead of the more common stationary form. Integration is carried out using formal time differential quotients of the Fourier coefficients. (orig./RW) [de

  12. A summary of the sources of input parameter values for the Waste Isolation Pilot Plant final porosity surface calculations

    International Nuclear Information System (INIS)

    Butcher, B.M.

    1997-08-01

    A summary of the input parameter values used in final predictions of closure and waste densification in the Waste Isolation Pilot Plant disposal room is presented, along with supporting references. These predictions are referred to as the final porosity surface data and will be used for WIPP performance calculations supporting the Compliance Certification Application to be submitted to the U.S. Environmental Protection Agency. The report includes tables and list all of the input parameter values, references citing their source, and in some cases references to more complete descriptions of considerations leading to the selection of values

  13. A summary of the sources of input parameter values for the Waste Isolation Pilot Plant final porosity surface calculations

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, B.M.

    1997-08-01

    A summary of the input parameter values used in final predictions of closure and waste densification in the Waste Isolation Pilot Plant disposal room is presented, along with supporting references. These predictions are referred to as the final porosity surface data and will be used for WIPP performance calculations supporting the Compliance Certification Application to be submitted to the U.S. Environmental Protection Agency. The report includes tables and list all of the input parameter values, references citing their source, and in some cases references to more complete descriptions of considerations leading to the selection of values.

  14. Load calculation methods for offshore wind turbine foundations

    DEFF Research Database (Denmark)

    Passon, Patrik; Branner, Kim

    2014-01-01

    Calculation of design loads for offshore wind turbine (OWT) foundations is typically performed in a joint effort between wind turbine manufactures and foundation designers (FDs). Ideally, both parties would apply the same fully integrated design tool and model for that purpose. However, such solu...

  15. Waste Isolation Pilot Plant Title I operator dose calculations. Final report, LATA report No. 90

    International Nuclear Information System (INIS)

    Hughes, P.S.; Rigdon, L.D.

    1980-02-01

    The radiation exposure dose was estimated for the Waste Isolation Pilot Plant (WIPP) operating personnel who do the unloading and transporting of the transuranic contact-handled waste. Estimates of the radiation source terms for typical TRU contact-handled waste were based on known composition and properties of the waste. The operations sequence for waste movement and storage in the repository was based upon the WIPP Title I data package. Previous calculations had been based on Conceptual Design Report data. A time and motion sequence was developed for personnel performing the waste handling operations both above and below ground. Radiation exposure calculations were then performed in several fixed geometries and folded with the time and motion studies for individual workers in order to determine worker exposure on an annual basis

  16. A balancing method for calculating a component raw involving CGF

    International Nuclear Information System (INIS)

    Kim, K.; Kang, D.; Yang, J.E.

    2004-01-01

    In this paper, a method called the 'Balancing Method' to derive a component RAW (Risk Achievement Worth) with basic event RAWs including a CCF (Common Cause Failure) RAW is summarized, and compared with the method proposed by the NEI (Nuclear Energy Institute) by mathematically checking the background on which the two methods are based. It is proved that the Balancing Method has a strong mathematically background. While the NEI method significantly underestimates the component RAW and is a little bit ad hoc in handling CCF RAW, the Balancing Method estimates the true component RAW very closely. Validity of the Balancing Method is based on the fact that if an component is out-of-service, it does not mean that the component is non-existent, but integrates the possibility that the component might fail due to CCF. The validity of the Balancing Method is proved by comparing it to the exact component RAW generated from the fault tree model

  17. Neutronic calculations for JET. Performed with the FURNACE2 program. (Final report JET contract JEO/9004)

    International Nuclear Information System (INIS)

    Verschuur, K.A.

    1996-10-01

    Neutron-transport calculations with the FURNACE(2) program system, in support of the Neutron Diagnostic Group at JET, have been performed since 1980, i.e. since the construction phase of JET. FURNACE(2) is a ray-tracing/multiple-reflection transport program system for toroidal geometries, that orginally was developed for blanket neutronics studies and which then was improved and extended for application to the neutron-diagnostics at JET. (orig./WL)

  18. Efficient Probability of Failure Calculations for QMU using Computational Geometry LDRD 13-0144 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Scott A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ebeida, Mohamed Salah [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Romero, Vicente J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swiler, Laura Painton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rushdi, Ahmad A. [Univ. of Texas, Austin, TX (United States); Abdelkader, Ahmad [Univ. of Maryland, College Park, MD (United States)

    2015-09-01

    This SAND report summarizes our work on the Sandia National Laboratory LDRD project titled "Efficient Probability of Failure Calculations for QMU using Computational Geometry" which was project #165617 and proposal #13-0144. This report merely summarizes our work. Those interested in the technical details are encouraged to read the full published results, and contact the report authors for the status of the software and follow-on projects.

  19. Advances in radiation modeling in ALEGRA :a final report for LDRD-67120, efficient implicit mulitgroup radiation calculations.

    Energy Technology Data Exchange (ETDEWEB)

    Mehlhorn, Thomas Alan; Kurecka, Christopher J. (University of Michigan, Ann Arbor, MI); McClarren, Ryan (University of Michigan, Ann Arbor, MI); Brunner, Thomas A.; Holloway, James Paul (University of Michigan, Ann Arbor, MI)

    2005-11-01

    The original LDRD proposal was to use a nonlinear diffusion solver to compute estimates for the material temperature that could then be used in a Implicit Monte Carlo (IMC) calculation. At the end of the first year of the project, it was determined that this was not going to be effective, partially due to the concept, and partially due to the fact that the radiation diffusion package was not as efficient as it could be. The second, and final year, of the project focused on improving the robustness and computational efficiency of the radiation diffusion package in ALEGRA. To this end, several new multigroup diffusion methods have been developed and implemented in ALEGRA. While these methods have been implemented, their effectiveness of reducing overall simulation run time has not been fully tested. Additionally a comprehensive suite of verification problems has been developed for the diffusion package to ensure that it has been implemented correctly. This process took considerable time, but exposed significant bugs in both the previous and new diffusion packages, the linear solve packages, and even the NEVADA Framework's parser. In order to manage this large suite of problem, a new tool called Tampa has been developed. It is a general tool for automating the process of running and analyzing many simulations. Ryan McClarren, at the University of Michigan has been developing a Spherical Harmonics capability for unstructured meshes. While still in the early phases of development, this promises to bridge the gap in accuracy between a full transport solution using IMC and the diffusion approximation.

  20. Advances in radiation modeling in ALEGRA: a final report for LDRD-67120, efficient implicit multigroup radiation calculations

    International Nuclear Information System (INIS)

    Mehlhorn, Thomas Alan; Kurecka, Christopher J.; McClarren, Ryan; Brunner, Thomas A.; Holloway, James Paul

    2005-01-01

    The original LDRD proposal was to use a nonlinear diffusion solver to compute estimates for the material temperature that could then be used in a Implicit Monte Carlo (IMC) calculation. At the end of the first year of the project, it was determined that this was not going to be effective, partially due to the concept, and partially due to the fact that the radiation diffusion package was not as efficient as it could be. The second, and final year, of the project focused on improving the robustness and computational efficiency of the radiation diffusion package in ALEGRA. To this end, several new multigroup diffusion methods have been developed and implemented in ALEGRA. While these methods have been implemented, their effectiveness of reducing overall simulation run time has not been fully tested. Additionally a comprehensive suite of verification problems has been developed for the diffusion package to ensure that it has been implemented correctly. This process took considerable time, but exposed significant bugs in both the previous and new diffusion packages, the linear solve packages, and even the NEVADA Framework's parser. In order to manage this large suite of problem, a new tool called Tampa has been developed. It is a general tool for automating the process of running and analyzing many simulations. Ryan McClarren, at the University of Michigan has been developing a Spherical Harmonics capability for unstructured meshes. While still in the early phases of development, this promises to bridge the gap in accuracy between a full transport solution using IMC and the diffusion approximation

  1. Biexponential analysis of diffusion-weighted imaging: comparison of three different calculation methods in transplanted kidneys.

    Science.gov (United States)

    Heusch, Philipp; Wittsack, Hans-Jörg; Pentang, Gael; Buchbender, Christian; Miese, Falk; Schek, Julia; Kröpil, Patric; Antoch, Gerald; Lanzman, Rotem S

    2013-12-01

    Biexponential analysis has been used increasingly to obtain contributions of both diffusion and microperfusion to the signal decay in diffusion-weighted imaging DWI of different parts of the body. To compare biexponential diffusion parameters of transplanted kidneys obtained with three different calculation methods. DWI was acquired in 15 renal allograft recipients (eight men, seven women; mean age, 52.4 ± 14.3 years) using a paracoronal EPI sequence with 16 b-values (b = 0-750 s/mm(2)) and six averages at 1.5T. No respiratory gating was used. Three different calculation methods were used for the calculation of biexponential diffusion parameters: Fp, ADCP, and ADCD were calculated without fixing any parameter a priori (calculation method 1); ADCP was fixed to 12.0 µm(2)/ms, whereas Fp and ADCD were calculated using the biexponential model (calculation method 2); multistep approach with monoexponential fitting of the high b-value portion (b ≥ 250 s/mm(2)) for determination of ADCD and assessment of the low b intercept for determination of Fp (calculation method 3). For quantitative analysis, ROI measurements were performed on the according parameter maps. Mean ADCD values of the renal cortex using calculation method 1 were significantly lower than using calculation methods 2 and 3 (P < 0.001). There was a significant correlation between calculation methods 1 and 2 (r = 0.69 (P < 0.005) and calculation methods 1 and 3 (r = 0.59; P < 0.05) as well as calculation methods 2 and 3 (r = 0.98; P < 0.001). Mean Fp values of the renal cortex were higher with calculation method 1 than with calculation methods 2 and 3 (P < 0.001). For Fp, only the correlation between calculation methods 2 and 3 was significant (r = 0.98; P < 0.001). Biexponential diffusion parameters differ significantly depending on the calculation methods used for their calculation.

  2. Classification of methods for annual energy harvesting calculations of photovoltaic generators

    International Nuclear Information System (INIS)

    Rus-Casas, C.; Aguilar, J.D.; Rodrigo, P.; Almonacid, F.; Pérez-Higueras, P.J.

    2014-01-01

    Highlights: • The paper presents a novel classification of methods for annual energy harvesting calculation of grid-connected PV systems. • The methods are classified in direct and indirect methods. • Direct methods directly calculate the energy. Indirect methods calculate the energy from the power. • The classification can help the PV professionals in order to choose the most suitable method for each application. - Abstract: Estimating the energy provided by the generators of grid-connected photovoltaic systems is important in order to analyze their economic viability and supervise their operation. The energy harvesting calculation of a photovoltaic generator is not trivial; there are a lot of methods for this calculation. The aim of this paper is to develop a novel classification of methods for annual energy harvesting calculation of a generator of a grid-connected photovoltaic system. The methods are classified in two groups: (1) those that indirectly calculate the energy, i.e. they first calculate the power and from this, they calculate the energy, and (2) those that directly calculate the energy. Furthermore, the indirect methods are grouped in two categories: those that first calculate the I–V curve of the generator and from this, they calculate the power, and those that directly calculate the power. The study has shown that the existing methods differ in simplicity and accuracy, so that the proposed classification is useful in order to choose the most suitable method for each specific application

  3. Calculation of pole profiles for the design of particle accelerators magnets. Equivalent current and conformal representation methods; Calcul de profils polaires destines a des aimants d'accelerateurs de particules. Methode des courants et methode des transformations conformes

    Energy Technology Data Exchange (ETDEWEB)

    Jaidane, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-04-01

    These two methods allow the determination of the shape of the poles in magnets, for a given field distribution in the air-gap. First method: The principle of the method consists to create the desired law of field by means of current sheets in which one can adjust the density given in a polynomial form. For the right distribution of these currents, the equipotential corresponding to the magnetic potential of the excitation coils is calculated. The pole profile of the H or C magnet identified with this equipotential line will finally take the place of the distribution of the current sheets used in the calculation. Steel permeability is assumed to be infinite and Foucault current effects are neglected in the case of variable fields. Second method: It consists to find a conformal representation that maps the pole profile plane upon the upper half of another plane where the equipotentials are two half straight lines, and where the field problems are easier to solve. Steel permeability is also considered to be infinite and the coils far from the pole faces. This known method has been applied to be compared with the first one. (author) [French] Ces deux methodes consistent a determiner la forme des pieces polaires d'aimants pour une distribution de champ determinee a l'avance dans l'entrefer. Premiere methode: Le principe de la methode consiste a creer la loi de champ desiree par l'intermediaire de nappes de courant dont on peut ajuster la densite exprimee sous une forme polynominale. Pour une distribution convenable de ces courants, on calcule l'equipotentielle correspondant au potentiel magnetique des bobines d'excitation. Le profil polaire d'un aimant en H ou C identifie a l'equipotentielle se substitue finalement a la repartition des nappes de courant utilisee dans la methode de calcul. La permeabilite de l'acier est supposee infinie et les courants de Foucault sont negliges dans le cas des champs variables. Seconde methode: Elle consiste a trouver une transformation

  4. The calculation of neutron flux using Monte Carlo method

    Science.gov (United States)

    Günay, Mehtap; Bardakçı, Hilal

    2017-09-01

    In this study, a hybrid reactor system was designed by using 99-95% Li20Sn80 + 1-5% RG-Pu, 99-95% Li20Sn80 + 1-5% RG-PuF4, and 99-95% Li20Sn80 + 1-5% RG-PuO2 fluids, ENDF/B-VII.0 evaluated nuclear data library and 9Cr2WVTa structural material. The fluids were used in the liquid first wall, liquid second wall (blanket) and shield zones of a fusion-fission hybrid reactor system. The neutron flux was calculated according to the mixture components, radial, energy spectrum in the designed hybrid reactor system for the selected fluids, library and structural material. Three-dimensional nucleonic calculations were performed using the most recent version MCNPX-2.7.0 the Monte Carlo code.

  5. Method of calculating heat transfer in furnaces of small power

    Directory of Open Access Journals (Sweden)

    Khavanov Pavel

    2016-01-01

    Full Text Available This publication presents the experiences and results of generalization criterion equation of importance in the analysis of the processes of heat transfer and thermal calculations of low-power heat generators cooled combustion chambers. With generalizing depending estimated contribution of radiation and convective heat transfer component in the complex for the combustion chambers of small capacity boilers. Determined qualitative and quantitative dependence of the integrated radiative-convective heat transfer from the main factors working combustion chambers of small volume.

  6. Experiences with leak rate calculations methods for LBB application

    International Nuclear Information System (INIS)

    Grebner, H.; Kastner, W.; Hoefler, A.; Maussner, G.

    1997-01-01

    In this paper, three leak rate computer programs for the application of leak before break analysis are described and compared. The programs are compared to each other and to results of an HDR Reactor experiment and two real crack cases. The programs analyzed are PIPELEAK, FLORA, and PICEP. Generally, the different leak rate models are in agreement. To obtain reasonable agreement between measured and calculated leak rates, it was necessary to also use data from detailed crack investigations

  7. Experiences with leak rate calculations methods for LBB application

    Energy Technology Data Exchange (ETDEWEB)

    Grebner, H.; Kastner, W.; Hoefler, A.; Maussner, G. [and others

    1997-04-01

    In this paper, three leak rate computer programs for the application of leak before break analysis are described and compared. The programs are compared to each other and to results of an HDR Reactor experiment and two real crack cases. The programs analyzed are PIPELEAK, FLORA, and PICEP. Generally, the different leak rate models are in agreement. To obtain reasonable agreement between measured and calculated leak rates, it was necessary to also use data from detailed crack investigations.

  8. Substep methods for burnup calculations with Bateman solutions

    International Nuclear Information System (INIS)

    Isotalo, A.E.; Aarnio, P.A.

    2011-01-01

    Highlights: → Bateman solution based depletion requires constant microscopic reaction rates. → Traditionally constant approximation is used for each depletion step. → Here depletion steps are divided to substeps which are solved sequentially. → This allows piecewise constant, rather than constant, approximation for each step. → Discretization errors are almost completely removed with only minor slowdown. - Abstract: When material changes in burnup calculations are solved by evaluating an explicit solution to the Bateman equations with constant microscopic reaction rates, one has to first predict the development of the reaction rates during the step and then further approximate these predictions with their averages in the depletion calculation. Representing the continuously changing reaction rates with their averages results in some error regardless of how accurately their development was predicted. Since neutronics solutions tend to be computationally expensive, steps in typical calculations are long and the resulting discretization errors significant. In this paper we present a simple solution to reducing these errors: the depletion steps are divided to substeps that are solved sequentially, allowing finer discretization of the reaction rates without additional neutronics solutions. This greatly reduces the discretization errors and, at least when combined with Monte Carlo neutronics, causes only minor slowdown as neutronics dominates the total running time.

  9. Identifying strategies to assist final semester nursing students to develop numeracy skills: a mixed methods study.

    Science.gov (United States)

    Ramjan, Lucie M; Stewart, Lyn; Salamonson, Yenna; Morris, Maureen M; Armstrong, Lyn; Sanchez, Paula; Flannery, Liz

    2014-03-01

    It remains a grave concern that many nursing students within tertiary institutions continue to experience difficulties with achieving medication calculation competency. In addition, universities have a moral responsibility to prepare proficient clinicians for graduate practice. This requires risk management strategies to reduce adverse medication errors post registration. To identify strategies and potential predictors that may assist nurse academics to tailor their drug calculation teaching and assessment methods. This project builds on previous experience and explores students' perceptions of newly implemented interventions designed to increase confidence and competence in medication calculation. This mixed method study surveyed students (n=405) enrolled in their final semester of study at a large, metropolitan university in Sydney, Australia. Tailored, contextualised interventions included online practice quizzes, simulated medication calculation scenarios developed for clinical practice classes, contextualised 'pen and paper' tests, visually enhanced didactic remediation and 'hands-on' contextualised workshops. Surveys were administered to students to determine their perceptions of interventions and to identify whether these interventions assisted with calculation competence. Test scores were analysed using SPSS v. 20 for correlations between students' perceptions and actual performance. Qualitative open-ended survey questions were analysed manually and thematically. The study reinforced that nursing students preferred a 'hands-on,' contextualised approach to learning that was 'authentic' and aligned with clinical practice. Our interventions assisted with supporting students' learning and improvement of calculation confidence. Qualitative data provided further insight into students' awareness of their calculation errors and preferred learning styles. Some of the strongest predictors for numeracy skill performance included (1) being an international student, (2

  10. Recently developed methods in neutral-particle transport calculations: overview

    International Nuclear Information System (INIS)

    Alcouffe, R.E.

    1982-01-01

    It has become increasingly apparent that successful, general methods for the solution of the neutral particle transport equation involve a close connection between the spatial-discretization method used and the source-acceleration method chosen. The first form of the transport equation, angular discretization which is discrete ordinates is considered as well as spatial discretization based upon a mesh arrangement. Characteristic methods are considered briefly in the context of future, desirable developments. The ideal spatial-discretization method is described as having the following attributes: (1) positive-positive boundary data yields a positive angular flux within the mesh including its boundaries; (2) satisfies the particle balance equation over the mesh, that is, the method is conservative; (3) possesses the diffusion limit independent of spatial mesh size, that is, for a linearly isotropic flux assumption, the transport differencing reduces to a suitable diffusion equation differencing; (4) the method is unconditionally acceleratable, i.e., for each mesh size, the method is unconditionally convergent with a source iteration acceleration. It is doubtful that a single method possesses all these attributes for a general problem. Some commonly used methods are outlined and their computational performance and usefulness are compared; recommendations for future development are detailed, which include practical computational considerations

  11. Raw material consumption of the European Union--concept, calculation method, and results.

    Science.gov (United States)

    Schoer, Karl; Weinzettel, Jan; Kovanda, Jan; Giegrich, Jürgen; Lauwigi, Christoph

    2012-08-21

    This article presents the concept, calculation method, and first results of the "Raw Material Consumption" (RMC) economy-wide material flow indicator for the European Union (EU). The RMC measures the final domestic consumption of products in terms of raw material equivalents (RME), i.e. raw materials used in the complete production chain of consumed products. We employed the hybrid input-output life cycle assessment method to calculate RMC. We first developed a highly disaggregated environmentally extended mixed unit input output table and then applied life cycle inventory data for imported products without appropriate representation of production within the domestic economy. Lastly, we treated capital formation as intermediate consumption. Our results show that services, often considered as a solution for dematerialization, account for a significant part of EU raw material consumption, which emphasizes the need to focus on the full production chains and dematerialization of services. Comparison of the EU's RMC with its domestic extraction shows that the EU is nearly self-sufficient in biomass and nonmetallic minerals but extremely dependent on direct and indirect imports of fossil energy carriers and metal ores. This implies an export of environmental burden related to extraction and primary processing of these materials to the rest of the world. Our results demonstrate that internalizing capital formation has significant influence on the calculated RMC.

  12. Numerical-analytical method of calculating insulated double-glazed units deflection under climatic (internal load

    Directory of Open Access Journals (Sweden)

    Plotnikov Aleksandr Aleksandrovich

    Full Text Available Glass unit consists of glasses hermetically-united together. The cavity of an insulating glass unit contains a fixed volume of air (gas. In the process of production regular air with atmospheric pressure and temperature is sealed inside a glass unit. During operation the atmospheric pressure is constantly changing, but the pressure inside remains constant (at a constant temperature. A change of temperature or of the external air pressure results in a pressure difference and therefore in a load on the glass panes. The action may exceed the usual load considerably. This pressure effects the glasses of the unit, deforms them, lowers the thermotechnical properties of glass units and can lead to their destruction. The action of the inside pressure can be seen all around as convex and concaved glasses, which destroys the architectural look of buildings. It is obvious that it is incorrect to calculate thin glass plates on such a load only by classical methods of strength of materials theory. In this case we need a special calculation method. The effects of a change in temperature, altitude or meteorological pressure are easily covered by the definition of an isochore pressure. This is necessary, to determine the change of pressure due to the temperature induced gas expansion in the cavity of the insulating glass according to the ideal gas law. After the integration of the analytical plate solution and the ideal gas law, the final pressure states can easily be calculated by coupling the change of volume and the change of pressure.

  13. Final results of the fifth three-dimensional dynamic Atomic Energy Research benchmark problem calculations

    International Nuclear Information System (INIS)

    Hadek, J.

    1999-01-01

    The paper gives a brief survey of the fifth three-dimensional dynamic Atomic Energy Research benchmark calculation results received with the code DYN3D/ATHLET at NRI Rez. This benchmark was defined at the seventh Atomic Energy Research Symposium (Hoernitz near Zittau, 1997). Its initiating event is a symmetrical break of the main steam header at the end of the first fuel cycle and hot shutdown conditions with one stuck out control rod group. The calculations were performed with the externally coupled codes ATHLET Mod.1.1 Cycle C and DYN3DH1.1/M3. The standard WWER-440/213 input deck of ATHLET code was adopted for benchmark purposes and for coupling with the code DYN3D. The first part of paper contains a brief characteristics of NPP input deck and reactor core model. The second part shows the time dependencies of important global and local parameters. In comparison with the results published at the eighth Atomic Energy Research Symposium (Bystrice nad Pernstejnem, 1998), the results published in this paper are based on improved ATHLET descriptions of control and safety systems. (Author)

  14. A balancing method for calculating a component raw involving CGF

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.; Kang, D.; Yang, J.E. [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, Daejon (Korea, Republic of)

    2004-07-01

    In this paper, a method called the 'Balancing Method' to derive a component RAW (Risk Achievement Worth) with basic event RAWs including a CCF (Common Cause Failure) RAW is summarized, and compared with the method proposed by the NEI (Nuclear Energy Institute) by mathematically checking the background on which the two methods are based. It is proved that the Balancing Method has a strong mathematically background. While the NEI method significantly underestimates the component RAW and is a little bit ad hoc in handling CCF RAW, the Balancing Method estimates the true component RAW very closely. Validity of the Balancing Method is based on the fact that if an component is out-of-service, it does not mean that the component is non-existent, but integrates the possibility that the component might fail due to CCF. The validity of the Balancing Method is proved by comparing it to the exact component RAW generated from the fault tree model.

  15. 7 CFR 51.308 - Methods of sampling and calculation of percentages.

    Science.gov (United States)

    2010-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Methods of Sampling and Calculation of Percentages § 51.308 Methods of sampling and calculation of percentages. (a) When the numerical... 7 Agriculture 2 2010-01-01 2010-01-01 false Methods of sampling and calculation of percentages. 51...

  16. Method of allowing for resonances in calculating reactivity values

    International Nuclear Information System (INIS)

    Kumpf, H.

    1985-01-01

    On the basis of the integral transport equation for the source density an expression has been derived for calculating reactivity values taking resonances in the core and in the sample into account. The model has been used for evaluating reactivities measured in the Rossendorf SEG IV configuration. It is shown that the influence of resonances in the core can be kept tolerable, if a sufficiently thick buffer zone of only slightly absorbing non-resonant material is arranged between the sample and the core. (author)

  17. Power operation, measurement and methods of calculation of power distribution

    International Nuclear Information System (INIS)

    Lindahl, S.O.; Bernander, O.; Olsson, S.

    1982-01-01

    During the initial fuel loading of a BWR core, extensive checks and measurements of the fuel are performed. The measurements are designed to verify that the reactor can always be safely operated in compliance with the regulatory constraints. The power distribution within the reactor core is evaluated by means of instrumentation and elaborate computer calculations. The power distribution forms the basis for the evaluation of thermal limits. The behaviour of the reactor during the ordinary modes of operation as well as during transients shall be well understood and such that the integrity of the fuel and the reactor systems is always well preserved. (author)

  18. Analysis of calculating methods for failure distribution function based on maximal entropy principle

    International Nuclear Information System (INIS)

    Guo Chunying; Lin Yuangen; Jiang Meng; Wu Changli

    2009-01-01

    The computation of invalidation distribution functions of electronic devices when exposed in gamma rays is discussed here. First, the possible devices failure distribution models are determined through the tests of statistical hypotheses using the test data. The results show that: the devices' failure distribution can obey multi-distributions when the test data is few. In order to decide the optimum failure distribution model, the maximal entropy principle is used and the elementary failure models are determined. Then, the Bootstrap estimation method is used to simulate the intervals estimation of the mean and the standard deviation. On the basis of this, the maximal entropy principle is used again and the simulated annealing method is applied to find the optimum values of the mean and the standard deviation. Accordingly, the electronic devices' optimum failure distributions are finally determined and the survival probabilities are calculated. (authors)

  19. Research on a wavefront aberration calculation method for a laser energy gradient attenuator

    International Nuclear Information System (INIS)

    Dong, Tingting; Han, Xu; Chen, Chi; Fu, Yuegang; Li, Ming

    2013-01-01

    When a laser energy gradient attenuator is working, there is an inhomogeneous temperature distribution in the whole of the glass because of the non-uniform light energy absorption. This will lead to optical performance reduction. An integrated opto-thermal–mechanical method is proposed to calculate the wavefront aberration for analysis of the thermal effect of the system. Non-sequential optical analysis is used for computing the absorbed energy distribution. The finite element analysis program solves the temperature distribution and the deformations of nodes on the surfaces. An interface routine is created to fit the surface shape and the index field, and extended Zernike polynomials are introduced to get a higher fitting precision. Finally, the parameters are imported to the CodeV optical design program automatically, and the user defined gradient index material is ray traced to obtain the wavefront aberration. The method can also be used in other optical systems for thermal effect analysis. (letter)

  20. Discussion on calculation method of overburden cover for radon reduction

    International Nuclear Information System (INIS)

    Liang Jianlong; Zhou Xinghuo; Zhou Ju; Liu Huijuan

    2010-01-01

    The article collects a large number of experimental results from domestic researchers with regard to soil overburden experimental methods. Based on analyzing experimental results, some questions in determining requirements for overburden cover thickness, data processing method and negative intercept have been dis- cussed. (authors)

  1. Comparison of source-term calculations using the AREST and SYVAC-Vault models: [Final report

    International Nuclear Information System (INIS)

    Apted, M.J.; Engel, D.W.; Garisto, N.C.; LeNeveu, D.M.

    1988-07-01

    A comparison of the calculated radionuclide release from a waste package in a geologic repository has been performed using the verified SYVAC-Vault Model and AREST Model. the purpose of this comparison is to further establish the credibility of these codes for predictive performance assessment and to identify improvements that may be required. A reference case for a Canadian conceptual design with spent fuel as the waste form was chosen to make an initial comparison. The results from the two models were in good agreement, including peak release rates, time to reach peak release, and long term release rates. Differences in results from the two models are attributed to differences in computational approaches. Studies of the effects of sorption, convective flow, distributed containment failure, and precipitation are identified as key areas for further comparisons and are currently in progress. 11 refs., 3 figs., 5 tabs

  2. ATHENA calculation model for the ITER-FEAT divertor cooling system. Final report with updates

    International Nuclear Information System (INIS)

    Eriksson, John; Sjoeberg, A.; Sponton, L.L.

    2001-05-01

    An ATHENA model of the ITER-FEAT divertor cooling system has been developed for the purpose of calculating and evaluating consequences of different thermal-hydraulic accidents as specified in the Accident Analysis Specifications for the ITER-FEAT Generic Site Safety Report. The model is able to assess situations for a variety of conceivable operational transients from small flow disturbances to more critical conditions such as total blackout caused by a loss of offsite and emergency power. The main objective for analyzing this type of scenarios is to determine margins against jeopardizing the integrity of the divertor cooling system components and pipings. The model of the divertor primary heat transport system encompasses the divertor cassettes, the port limiter systems, the pressurizer, the heat exchanger and all feed and return pipes of these components. The development was pursued according to practices and procedures outlined in the ATHENA code manuals using available modelling components such as volumes, junctions, heat structures and process controls

  3. Input of biomass in power plants for power generation. Calculation of the financial gap. Final report

    International Nuclear Information System (INIS)

    Van Tilburg, X.; De Vries, H.J.; Pfeiffer, A.E.; Cleijne, J.W.

    2005-09-01

    The Ministry of Economic Affairs has requested ECN and KEMA to answer two questions. (1) Are the costs and benefits of projects in which wood-pellets are co-fired in a coal fired power plant representative for those of bio-oil fueled co-firing projects in a gas fired plant?; and (2) Are new projects representative for existing projects? To answer these questions, ECN and KEMA have calculated the financial gaps in six different situations: co-firing bio-oil in a gas fired power plant; co-firing bio-oil in a coal fired power plant; gasification of solid biomass; co-firing wood pellets in a coal fired power plant; co-firing agricultural residues in a coal fired power plant; and co-firing waste wood (A- and B-grade) in a coal fired power plant. The ranges and reference cases show that co-firing bio-oil on average has a smaller financial gap than the solid biomass reference case. On average it can also be concluded that when using waste wood or agro-residues, the financial gaps are smaller. Based on these findings it is concluded that: (1) The reference case of co-firing wood pellets in a coal fired power plant are not representative for bio-fuel options. A new category for bio-oil options seems appropriate; and (2) The financial gap of new projects as calculated in November 2004, is often higher then the ranges for existing projects indicate [nl

  4. An empirical method for calculating thermodynamic parameters for U(6) phases, applications to performance assessment calculations

    International Nuclear Information System (INIS)

    Ewing, R.C.; Chen, F.; Clark, S.B.

    2002-01-01

    Uranyl minerals form by oxidation and alteration of uraninite, UO 2+x , and the UO 2 in used nuclear fuels. The thermodynamic database for these phases is extremely limited. However, the Gibbs free energies and enthalpies for uranyl phases may be estimated based on a method that sums polyhedral contributions. The molar contributions of the structural components to Δ f G m 0 and Δ f H m 0 are derived by multiple regression using the thermodynamic data of phases for which the crystal structures are known. In comparison with experimentally determined values, the average residuals associated with the predicted Δ f G m 0 and Δ f H m 0 for the uranyl phases used in the model are 0.08 and 0.10%, respectively. There is also good agreement between the predicted mineral stability relations and field occurrences, thus providing confidence in this method for the estimation of Δ f G m 0 and Δ f H m 0 of the U(VI) phases. This approach provides a means of generating estimated thermodynamic data for performance assessment calcination and a basic for making bounding calcination of phase stabilities and solubilities. (author)

  5. Calculation of radiation exposure in diagnostic radiology. Method and surveys

    International Nuclear Information System (INIS)

    Duvauferrier, R.; Ramee, A.; Ezzeldin, K.; Guibert, J.L.

    1984-01-01

    A computerized method for evaluating the radiation exposure of the main target organs during various diagnostic radiologic procedures is described. This technique was used for educational purposes: study of exposure variations according to the technical modalities of a given procedure, and study of exposure variations according to various technical protocols (IVU, EGD barium study, etc.). This method was also used for studying exposure of patients during hospitalization in the Rennes Regional Hospital Center (France) in 1982, according to departments (urology, neurology, etc.). This method and results of these three studies are discussed [fr

  6. A nonlinear analytic function expansion nodal method for transient calculations

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Han Gyn; Park, Sang Yoon; Cho, Byung Oh; Zee, Sung Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation of the solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized, In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of application to the NEACRP PWR rod ejection benchmark problems. 6 refs., 2 figs., 1 tab. (Author)

  7. A nonlinear analytic function expansion nodal method for transient calculations

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Han Gyn; Park, Sang Yoon; Cho, Byung Oh; Zee, Sung Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1999-12-31

    The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation of the solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized, In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of application to the NEACRP PWR rod ejection benchmark problems. 6 refs., 2 figs., 1 tab. (Author)

  8. Criticism of the OPW method for band structure calculations

    International Nuclear Information System (INIS)

    Lendi, K.

    1977-01-01

    The OPW method is associated with a general eigenvalue problem of type (A - lambda B) x vector = 0, in which the matrix B and in particular its lowest eigenvalue decide upon the stability of the solutions lambda and, therefore, upon the applicability of the method which may become very questionable for heavier substances. Analytical proofs as well as explicit numerical estimates for several solids are given [pt

  9. Use of deterministic methods in survey calculations for criticality problems

    International Nuclear Information System (INIS)

    Hutton, J.L.; Phenix, J.; Course, A.F.

    1991-01-01

    A code package using deterministic methods for solving the Boltzmann Transport equation is the WIMS suite. This has been very successful for a range of situations. In particular it has been used with great success to analyse trends in reactivity with a range of changes in state. The WIMS suite of codes have a range of methods and are very flexible in the way they can be combined. A wide variety of situations can be modelled ranging through all the current Thermal Reactor variants to storage systems and items of chemical plant. These methods have recently been enhanced by the introduction of the CACTUS method. This is based on a characteristics technique for solving the Transport equation and has the advantage that complex geometrical situations can be treated. In this paper the basis of the method is outlined and examples of its use are illustrated. In parallel with these developments the validation for out of pile situations has been extended to include experiments with relevance to criticality situations. The paper will summarise this evidence and show how these results point to a partial re-adoption of deterministic methods for some areas of criticality. The paper also presents results to illustrate the use of WIMS in criticality situations and in particular show how it can complement codes such as MONK when used for surveying the reactivity effect due to changes in geometry or materials. (Author)

  10. Energy conservation for houses and its calculation methods

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S H

    1981-04-01

    The concept of energy conservation of houses has been developed and began to be applied widely since the first oil crisis. Now we can say definitely that insulating a house is the most effective way of saving energy, and the renewable energy sources are useful only when the demand for space heating and hot water is minimized by insulating. If a house is well insulated, it will need a much smaller, simpler and cheaper heating system. So it will be less efficient to put a solar collector and wind generator on a poorly insulated house. Architects and engineers should have a certain level of practical knowledge of insulation for house to persuade customers using insulating materials and structure. Moreover, it is very essential to amend the existing building codes in order to facilitate this basic necessity. For instance, the Building Regulations of Denmark requires a U-value of 0.4 W/m/sup 2/ degC for heavy weight external wall. If the cavity wall has outer and inner leaf of just normal brick with internal finish of 20 mm cement mortar, which is a typical wall construction for houses in Korea, the thickness of insulation materials to the cavity can be calculated in order to fullfil the U-value of 0.4 W/m/sup 2/ degC in addition to the cavity of the external heavy wall: expanded polyurethane 58 mm, urea formaldehyde foam 67 mm, expanded polystyrene 78 mm, mineral wool 94 mm. The economic feasibility of solar heating system has been calculated. By applying 25% of the year inflation ratio for fuel cost, the result turns out economically comparable with solar heating systems.

  11. Calculation of free-energy differences from computer simulations of initial and final states

    International Nuclear Information System (INIS)

    Hummer, G.; Szabo, A.

    1996-01-01

    A class of simple expressions of increasing accuracy for the free-energy difference between two states is derived based on numerical thermodynamic integration. The implementation of these formulas requires simulations of the initial and final (and possibly a few intermediate) states. They involve higher free-energy derivatives at these states which are related to the moments of the probability distribution of the perturbation. Given a specified number of such derivatives, these integration formulas are optimal in the sense that they are exact to the highest possible order of free-energy perturbation theory. The utility of this approach is illustrated for the hydration free energy of water. This problem provides a quite stringent test because the free energy is a highly nonlinear function of the charge so that even fourth order perturbation theory gives a very poor estimate of the free-energy change. Our results should prove most useful for complex, computationally demanding problems where free-energy differences arise primarily from changes in the electrostatic interactions (e.g., electron transfer, charging of ions, protonation of amino acids in proteins). copyright 1996 American Institute of Physics

  12. The use of symbolic computation in radiative, energy, and neutron transport calculations. Final report

    International Nuclear Information System (INIS)

    Frankel, J.I.

    1997-01-01

    This investigation used sysmbolic manipulation in developing analytical methods and general computational strategies for solving both linear and nonlinear, regular and singular integral and integro-differential equations which appear in radiative and mixed-mode energy transport. Contained in this report are seven papers which present the technical results as individual modules

  13. Coherent control of photoabsorption processes and calculation of nonlinear optical processes. Final technical report

    International Nuclear Information System (INIS)

    Lambropoulos, P.

    1998-01-01

    The work on the grant for the entire period of its duration concentrated on two different but related areas, namely coherent control of photoabsorption processes and the calculation of non linear optical processes with short wavelength radiation. On the first topic, the work dealt with the problem of controlling the population transfer from one to another bound state of a system in a route that passes through a continuum. This question is most important in the context of transferring populations between vibrational states of a molecule through a sequence of two pulses taking the system via the dissociation continuum. On the second topic, their work was motivated by the availability of XUV and soft X-ray coherent radiation sources obtained through high order harmonic generation. In addition, a few other techniques based on schemes of photo-pumped X-ray lasers promise to provide in the near-future similarly coherent sources. It is thus important to have an assessment of the possibility of extending non-linear optical processes to this range of wavelengths. This means assessing the relevant magnitude of the susceptibilities for third harmonic generation, stimulated Raman scattering, two-photon absorption, etc

  14. Transport survey calculations using the spectral collocation method

    International Nuclear Information System (INIS)

    Painter, S.L.; Lyon, J.F.

    1989-01-01

    A novel transport survey code has been developed and is being used to study the sensitivity of stellarator reactor performance to various transport assumptions. Instead of following one of the usual approaches, the steady-state transport equation are solved in integral form using the spectral collocation method. This approach effectively combine the computational efficiency of global models with the general nature of 1-D solutions. A compact torsatron reactor test case was used to study the convergence properties and flexibility of the new method. The heat transport model combined Shaing's model for ripple-induced neoclassical transport, the Chang-Hinton model for axisymmetric neoclassical transport, and neoalcator scaling for anomalous electron heat flux. Alpha particle heating, radiation losses, classical electron-ion heat flow, and external heating were included. For the test problem, the method exhibited some remarkable convergence properties. As the number of basis functions was increased, the maximum, pointwise error in the integrated power balance decayed exponentially until the numerical noise level as reached. Better than 10% accuracy in the globally-averaged quantities was achieved with only 5 basis functions; better than 1% accuracy was achieved with 10 basis functions. The numerical method was also found to be very general. Extreme temperature gradients at the plasma edge which sometimes arise from the neoclassical models and are difficult to resolve with finite-difference methods were easily resolved. 8 refs., 6 figs

  15. Analytical method of spectra calculations in the Bargmann representation

    International Nuclear Information System (INIS)

    Maciejewski, Andrzej J.; Przybylska, Maria; Stachowiak, Tomasz

    2014-01-01

    We formulate a universal method for solving an arbitrary quantum system which, in the Bargmann representation, is described by a system of linear equations with one independent variable, such as one- and multi-photon Rabi models, or N level systems interacting with a single mode of the electromagnetic field and their various generalizations. We explain three types of conditions that determine the spectrum and show their usage for two deformations of the Rabi model. We prove that the spectra of both models are just zeros of transcendental functions, which in one case are given explicitly in terms of confluent Heun functions. - Highlights: • Analytical method of spectrum determination in Bargmann representation is proposed. • Three types of conditions determining spectrum are identified. • Method to two generalizations of the Rabi system is applied

  16. Application of γ field theory based calculation method to the monitoring of mine nuclear radiation environment

    International Nuclear Information System (INIS)

    Du Yanjun; Liu Qingcheng; Liu Hongzhang; Qin Guoxiu

    2009-01-01

    In order to find the feasibility of calculating mine radiation dose based on γ field theory, this paper calculates the γ radiation dose of a mine by means of γ field theory based calculation method. The results show that the calculated radiation dose is of small error and can be used to monitor mine environment of nuclear radiation. (authors)

  17. A predictive mathematical model for the calculation of the final mass of Graves' disease thyroids treated with 131I

    Science.gov (United States)

    Traino, Antonio C.; Di Martino, Fabio; Grosso, Mariano; Monzani, Fabio; Dardano, Angela; Caraccio, Nadia; Mariani, Giuliano; Lazzeri, Mauro

    2005-05-01

    Substantial reductions in thyroid volume (up to 70-80%) after radioiodine therapy of Graves' hyperthyroidism are common and have been reported in the literature. A relationship between thyroid volume reduction and outcome of 131I therapy of Graves' disease has been reported by some authors. This important result could be used to decide individually the optimal radioiodine activity A0 (MBq) to administer to the patient, but a predictive model relating the change in gland volume to A0 is required. Recently, a mathematical model of thyroid mass reduction during the clearance phase (30-35 days) after 131I administration to patients with Graves' disease has been published and used as the basis for prescribing the therapeutic thyroid absorbed dose. It is well known that the thyroid volume reduction goes on until 1 year after therapy. In this paper, a mathematical model to predict the final mass of Graves' diseased thyroids submitted to 131I therapy is presented. This model represents a tentative explanation of what occurs macroscopically after the end of the clearance phase of radioiodine in the gland (the so-called second-order effects). It is shown that the final thyroid mass depends on its basal mass, on the radiation dose absorbed by the gland and on a constant value α typical of thyroid tissue. α has been evaluated based on a set of measurements made in 15 reference patients affected by Graves' disease and submitted to 131I therapy. A predictive equation for the calculation of the final mass of thyroid is presented. It is based on macroscopic parameters measurable after a diagnostic 131I capsule administration (0.37-1.85 MBq), before giving the therapy. The final mass calculated using this equation is compared to the final mass of thyroid measured 1 year after therapy administration in 22 Graves' diseased patients. The final masses calculated and measured 1 year after therapy are in fairly good agreement (R = 0.81). The possibility, for the physician, to decide a

  18. A predictive mathematical model for the calculation of the final mass of Graves' disease thyroids treated with 131I

    International Nuclear Information System (INIS)

    Traino, Antonio C; Martino, Fabio Di; Grosso, Mariano; Monzani, Fabio; Dardano, Angela; Caraccio, Nadia; Mariani, Giuliano; Lazzeri, Mauro

    2005-01-01

    Substantial reductions in thyroid volume (up to 70-80%) after radioiodine therapy of Graves' hyperthyroidism are common and have been reported in the literature. A relationship between thyroid volume reduction and outcome of 131 I therapy of Graves' disease has been reported by some authors. This important result could be used to decide individually the optimal radioiodine activity A 0 (MBq) to administer to the patient, but a predictive model relating the change in gland volume to A 0 is required. Recently, a mathematical model of thyroid mass reduction during the clearance phase (30-35 days) after 131 I administration to patients with Graves' disease has been published and used as the basis for prescribing the therapeutic thyroid absorbed dose. It is well known that the thyroid volume reduction goes on until 1 year after therapy. In this paper, a mathematical model to predict the final mass of Graves' diseased thyroids submitted to 131 I therapy is presented. This model represents a tentative explanation of what occurs macroscopically after the end of the clearance phase of radioiodine in the gland (the so-called second-order effects). It is shown that the final thyroid mass depends on its basal mass, on the radiation dose absorbed by the gland and on a constant value α typical of thyroid tissue. α has been evaluated based on a set of measurements made in 15 reference patients affected by Graves' disease and submitted to 131 I therapy. A predictive equation for the calculation of the final mass of thyroid is presented. It is based on macroscopic parameters measurable after a diagnostic 131 I capsule administration (0.37-1.85 MBq), before giving the therapy. The final mass calculated using this equation is compared to the final mass of thyroid measured 1 year after therapy administration in 22 Graves' diseased patients. The final masses calculated and measured 1 year after therapy are in fairly good agreement (R = 0.81). The possibility, for the physician, to

  19. Ab initio calculations of mechanical properties: Methods and applications

    Czech Academy of Sciences Publication Activity Database

    Pokluda, J.; Černý, Miroslav; Šob, Mojmír; Umeno, Y.

    2015-01-01

    Roč. 73, AUG (2015), s. 127-158 ISSN 0079-6425 R&D Projects: GA ČR(CZ) GAP108/12/0311 Institutional support: RVO:68081723 Keywords : Ab initio methods * Elastic moduli * Intrinsic hardness * Stability analysis * Theoretical strength * Intrinsic brittleness/ductility Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 31.083, year: 2015

  20. Spectral calculations in magnetohydrodynamics using the Jacobi-Davidson method

    NARCIS (Netherlands)

    Belien, A. J. C.; van der Holst, B.; Nool, M.; van der Ploeg, A.; Goedbloed, J. P.

    2001-01-01

    For the solution of the generalized complex non-Hermitian eigenvalue problems Ax = lambda Bx occurring in the spectral study of linearized resistive magnetohydrodynamics (MHD) a new parallel solver based on the recently developed Jacobi-Davidson [SIAM J. Matrix Anal. Appl. 17 (1996) 401] method has

  1. Final Report for 'Design calculations for high-space-charge beam-to-RF conversion'

    International Nuclear Information System (INIS)

    Smithe, David N.

    2008-01-01

    Accelerator facility upgrades, new accelerator applications, and future design efforts are leading to novel klystron and IOT device concepts, including multiple beam, high-order mode operation, and new geometry configurations of old concepts. At the same time, a new simulation capability, based upon finite-difference 'cut-cell' boundaries, has emerged and is transforming the existing modeling and design capability with unparalleled realism, greater flexibility, and improved accuracy. This same new technology can also be brought to bear on a difficult-to-study aspect of the energy recovery linac (ERL), namely the accurate modeling of the exit beam, and design of the beam dump for optimum energy efficiency. We have developed new capability for design calculations and modeling of a broad class of devices which convert bunched beam kinetic energy to RF energy, including RF sources, as for example, klystrons, gyro-klystrons, IOT's, TWT's, and other devices in which space-charge effects are important. Recent advances in geometry representation now permits very accurate representation of the curved metallic surfaces common to RF sources, resulting in unprecedented simulation accuracy. In the Phase I work, we evaluated and demonstrated the capabilities of the new geometry representation technology as applied to modeling and design of output cavity components of klystron, IOT's, and energy recovery srf cavities. We identified and prioritized which aspects of the design study process to pursue and improve in Phase II. The development and use of the new accurate geometry modeling technology on RF sources for DOE accelerators will help spark a new generational modeling and design capability, free from many of the constraints and inaccuracy associated with the previous generation of 'stair-step' geometry modeling tools. This new capability is ultimately expected to impact all fields with high power RF sources, including DOE fusion research, communications, radar and other

  2. Calculation method for control rod dropping time in reactor

    International Nuclear Information System (INIS)

    Nogami, Takeki; Kato, Yoshifumi; Ishino, Jun-ichi; Doi, Isamu.

    1996-01-01

    If a control rod starts dropping, the dropping speed is rapidly increased, then settled substantially constant, rapidly decreased when it reaches a dash pot. A second detection signal generated by removing an AC component from a first detection signal is differentiated twice. The time when the maximum value among the twice differentiated values is generated is determined as a time when the control rods starts dropping. The time when minimum value among the twice differentiated values is generated is determined as a time when the control rod reaches the dash pot of the reactor. The measuring time within a range from the time when the control rod starts dropping to the time when the control rod reaches the dash pot of the reactor is determined. As a result, processing for the calculation of the dropping start time and dash pot reaching time of the control rod can be automatized. Further, it is suffice to conduct differentiation twice till the reaching time, which can facilitate the processing thereby enabling to determine a reliable time range. (N.H.)

  3. Direct Calculation of Permeability by High-Accurate Finite Difference and Numerical Integration Methods

    KAUST Repository

    Wang, Yi

    2016-07-21

    Velocity of fluid flow in underground porous media is 6~12 orders of magnitudes lower than that in pipelines. If numerical errors are not carefully controlled in this kind of simulations, high distortion of the final results may occur [1-4]. To fit the high accuracy demands of fluid flow simulations in porous media, traditional finite difference methods and numerical integration methods are discussed and corresponding high-accurate methods are developed. When applied to the direct calculation of full-tensor permeability for underground flow, the high-accurate finite difference method is confirmed to have numerical error as low as 10-5% while the high-accurate numerical integration method has numerical error around 0%. Thus, the approach combining the high-accurate finite difference and numerical integration methods is a reliable way to efficiently determine the characteristics of general full-tensor permeability such as maximum and minimum permeability components, principal direction and anisotropic ratio. Copyright © Global-Science Press 2016.

  4. Comparative study of in situ methods for potential and actual evapotranspiration determination and their calculation by simulation model

    International Nuclear Information System (INIS)

    Kolev, B.

    2006-01-01

    Four in situ methods for potential and actual evapotranspiration determining were compared: neutron gauge, tensiometers, gypsum blocks and lysimeters. The actual and potential evapotranspiration were calculated by water balance equation and by using a simulation model for their determination. The aim of this study was mainly pointed on calculations of water use efficiency and transpiration coefficient in potential production situation. This makes possible to choose the best way for water consumption optimization for a given crop. The final results find with the best of the methods could be used for applying the principles of sustainable agricultural production in random object of Bulgarian agricultural area

  5. Development of High Precision Tsunami Runup Calculation Method Coupled with Structure Analysis

    Science.gov (United States)

    Arikawa, Taro; Seki, Katsumi; Chida, Yu; Takagawa, Tomohiro; Shimosako, Kenichiro

    2017-04-01

    The 2011 Great East Japan Earthquake (GEJE) has shown that tsunami disasters are not limited to inundation damage in a specified region, but may destroy a wide area, causing a major disaster. Evaluating standing land structures and damage to them requires highly precise evaluation of three-dimensional fluid motion - an expensive process. Our research goals were thus to develop a coupling STOC-CADMAS (Arikawa and Tomita, 2016) coupling with the structure analysis (Arikawa et. al., 2009) to efficiently calculate all stages from tsunami source to runup including the deformation of structures and to verify their applicability. We also investigated the stability of breakwaters at Kamaishi Bay. Fig. 1 shows the whole of this calculation system. The STOC-ML simulator approximates pressure by hydrostatic pressure and calculates the wave profiles based on an equation of continuity, thereby lowering calculation cost, primarily calculating from a e epi center to the shallow region. As a simulator, STOC-IC solves pressure based on a Poisson equation to account for a shallower, more complex topography, but reduces computation cost slightly to calculate the area near a port by setting the water surface based on an equation of continuity. CS3D also solves a Navier-Stokes equation and sets the water surface by VOF to deal with the runup area, with its complex surfaces of overflows and bores. STR solves the structure analysis including the geo analysis based on the Biot's formula. By coupling these, it efficiently calculates the tsunami profile from the propagation to the inundation. The numerical results compared with the physical experiments done by Arikawa et. al.,2012. It was good agreement with the experimental ones. Finally, the system applied to the local situation at Kamaishi bay. The almost breakwaters were washed away, whose situation was similar to the damage at Kamaishi bay. REFERENCES T. Arikawa and T. Tomita (2016): "Development of High Precision Tsunami Runup

  6. Analytic moment method calculations of the drift wave spectrum

    International Nuclear Information System (INIS)

    Thayer, D.R.; Molvig, K.

    1985-11-01

    A derivation and approximate solution of renormalized mode coupling equations describing the turbulent drift wave spectrum is presented. Arguments are given which indicate that a weak turbulence formulation of the spectrum equations fails for a system with negative dissipation. The inadequacy of the weak turbulence theory is circumvented by utilizing a renormalized formation. An analytic moment method is developed to approximate the solution of the nonlinear spectrum integral equations. The solution method employs trial functions to reduce the integral equations to algebraic equations in basic parameters describing the spectrum. An approximate solution of the spectrum equations is first obtained for a mode dissipation with known solution, and second for an electron dissipation in the NSA

  7. Method for Calculation of Steam-Compression Heat Transformers

    Directory of Open Access Journals (Sweden)

    S. V. Zditovetckaya

    2012-01-01

    Full Text Available The paper considers a method for joint numerical analysis of cycle parameters and heatex-change equipment of steam-compression heat transformer contour that takes into account a non-stationary operational mode and irreversible losses in devices and pipeline contour. The method has been realized in the form of the software package and can be used while making design or selection of a heat transformer with due account of a coolant and actual equipment being included in its structure.The paper presents investigation results revealing influence of pressure loss in an evaporator and a condenser from the side of the coolant caused by a friction and local resistance on power efficiency of the heat transformer which is operating in the mode of refrigerating and heating installation and a thermal pump. Actually obtained operational parameters of the thermal pump in the nominal and off-design operatinal modes depend on the structure of the concrete contour equipment.

  8. The DV-Xα molecular-orbital calculation method

    CERN Document Server

    Ishii, Tomohiko; Ogasawara, Kazuyoshi

    2014-01-01

    This multi-author contributed volume contains chapters featuring the development of the DV-Xα method and its application to a variety of problems in Materials Science and Spectroscopy written by leaders of the respective fields. The volume contains a Foreword written by the Chairs of Japanese and Korea DV-X alpha Societies. This book is aimed at individuals working in Quantum Chemistry.

  9. The power series method in the effectiveness factor calculations

    OpenAIRE

    Filipich, C. P.; Villa, L. T.; Grossi, Ricardo Oscar

    2017-01-01

    In the present paper, exact analytical solutions are obtained for nonlinear ordinary differential equations which appear in complex diffusionreaction processes. A technique based on the power series method is used. Numerical results were computed for a number of cases which correspond to boundary value problems available in the literature. Additionally, new numerical results were generated for several important cases. Fil: Filipich, C. P.. Universidad Tecnológica Nacional. Facultad Regiona...

  10. Methods for the calculation of uncertainty in analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Suh, M. Y.; Sohn, S. C.; Park, Y. J.; Park, K. K.; Jee, K. Y.; Joe, K. S.; Kim, W. H

    2000-07-01

    This report describes the statistical rules for evaluating and expressing uncertainty in analytical chemistry. The procedures for the evaluation of uncertainty in chemical analysis are illustrated by worked examples. This report, in particular, gives guidance on how uncertainty can be estimated from various chemical analyses. This report can be also used for planning the experiments which will provide the information required to obtain an estimate of uncertainty for the method.

  11. Feasibility study on heterogeneous method in criticality calculations

    International Nuclear Information System (INIS)

    Prati, A.

    1977-01-01

    The criticality of finite heterogeneous assemblies is analysed by the heterogeneous methods employing the Eigen-function analysis. The moderation is treated by the Fermi age theory. The system is analysed in two dimensional rectangular coordinates. The criticality and the fluxes are determined for systems with small and large number of fuel rods. The convergence and the residual error in the modal analysis are discussed. (author)

  12. Research on stochastic power-flow study methods. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Heydt, G. T. [ed.

    1981-01-01

    A general algorithm to determine the effects of uncertainty in bus load and generation on the output of conventional power flow analysis is presented. The use of statistical moments is presented and developed as a means for representing the stochastic process. Statistical moments are used to describe the uncertainties, and facilitate the calculations of single and multivarlate probability density functions of input and output variables. The transformation of the uncertainty through the power flow equations is made by the expansion of the node equations in a multivariate Taylor series about an expected operating point. The series is truncated after the second order terms. Since the power flow equations are nonlinear, the expected values of output quantities is in general not the solution to the conventional load flow problem using expected values of input quantities. The second order transformation offers a correction vector and allows the consideration of larger uncertainties which have caused significant error in the current linear transformation algorithms. Voltage controlled busses are included with consideration of upper and lower limits. The finite reactive power available at generation sites, and fixed ranges of transformer tap movement may have a significant effect on voltage and line power flow statistics. A method is given which considers limitation constraints in the evaluation of all output quantities. The bus voltages, line power flows, transformer taps, and generator reactive power requirements are described by their statistical moments. Their values are expressed in terms of the probability that they are above or below specified limits, and their expected values given that they do fall outside the limits. Thus the algorithm supplies information about severity of overload as well as probability of occurrence. An example is given for an eleven bus system, evaluating each quantity separately. The results are compared with Monte Carlo simulation.

  13. A combination between the differential and the perturbation theory methods for calculating sensitivity coefficients

    International Nuclear Information System (INIS)

    Borges, Antonio Andrade

    1998-01-01

    A new method for the calculation of sensitivity coefficients is developed. The new method is a combination of two methodologies used for calculating theses coefficients, which are the differential and the generalized perturbation theory methods. The method utilizes as integral parameter the average flux in an arbitrary region of the system. Thus, the sensitivity coefficient contains only the component corresponding to the neutron flux. To obtain the new sensitivity coefficient, the derivatives of the integral parameter, Φ, with respect to σ are calculated using the perturbation method and the functional derivatives of this generic integral parameter with respect to σ and Φ are calculated using the differential method. (author)

  14. An improved filtered spherical harmonic method for transport calculations

    International Nuclear Information System (INIS)

    Ahrens, C.; Merton, S.

    2013-01-01

    Motivated by the work of R. G. McClarren, C. D. Hauck, and R. B. Lowrie on a filtered spherical harmonic method, we present a new filter for such numerical approximations to the multi-dimensional transport equation. In several test problems, we demonstrate that the new filter produces results with significantly less Gibbs phenomena than the filter used by McClarren, Hauck and Lowrie. This reduction in Gibbs phenomena translates into propagation speeds that more closely match the correct propagation speed and solutions that have fewer regions where the scalar flux is negative. (authors)

  15. Simplified hourly method to calculate summer temperatures in dwellings

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Aggerholm, Søren

    2012-01-01

    with an ordinary distribution of windows and a “worst” case where the window area facing south and west was increased by more than 60%. The simplified method used Danish weather data and only needs information on transmission losses, thermal mass, surface contact, internal load, ventilation scheme and solar load...... program for thermal simulations of buildings. The results are based on one year simulations of two cases. The cases were based on a low energy dwelling of 196 m². The transmission loss for the building envelope was 3.3 W/m², not including windows and doors. The dwelling was tested in two cases, a case...

  16. Methods of calculating engineering parameters for gas separations

    Science.gov (United States)

    Lawson, D. D.

    1980-01-01

    A group additivity method has been generated which makes it possible to estimate, from the structural formulas alone, the energy of vaporization and the molar volume at 25 C of many nonpolar organic liquids. From these two parameters and appropriate thermodynamic relationships it is then possible to predict the vapor pressure of the liquid phase and the solubility of various gases in nonpolar organic liquids. The data are then used to evaluate organic and some inorganic liquids for use in gas separation stages or as heat exchange fluids in prospective thermochemical cycles for hydrogen production.

  17. The rationale for selecting the method of calculation of project products coast (works, services

    Directory of Open Access Journals (Sweden)

    O. V. Molchanova

    2017-01-01

    Full Text Available In modern conditions of management it is necessary to develop a number of recommendations on the introduction of management accounting at state-owned enterprises that carry out revenue-generating activities or based on the right of economic management. It is necessary to apply the correct cost-accounting method for the production of products, works, services for a more rational calculation of the cost price. This will allow management personnel to receive timely objective information about their cost price, identify the feasibility of production and sales, justify the assortment, plan profits. The procedure for determining the cost price of the project products (works, services in the theory and practice of the state enterprise of the Astrakhan region “Kasprybproekt” is investigated in the work. With the existing practice of planning in design organizations, the planned cost price of design and survey works for established cost items is planned in the cost estimate for production by the design organization as a whole and by the types of work: design, survey and others, without subdividing it by orders (projects. According to this, accounting of the actual costs for work in the design organizations is based. The study showed that the state enterprise of the Astrakhan region “Kasprybproyekt” performs different projects with different execution periods; therefore, it is advisable to use one method of calculating the cost price - job (order costing method, and link it to the responsibility centers depending on the department of the performer. Based on the research of the used method to the cost price calculate of the project products (works, services in the state enterprise of the Astrakhan region “Kasprybproekt”, it was proposed to use the job (order costing method that allows to detail all the project costs without distorting the final financial result and optimize the project costs. If the calculation method is correctly determined

  18. A New Method for Calculating Counts in Cells

    Science.gov (United States)

    Szapudi, István

    1998-04-01

    In the near future, a new generation of CCD-based galaxy surveys will enable high-precision determination of the N-point correlation functions. The resulting information will help to resolve the ambiguities associated with two-point correlation functions, thus constraining theories of structure formation, biasing, and Gaussianity of initial conditions independently of the value of Ω. As one of the most successful methods of extracting the amplitude of higher order correlations is based on measuring the distribution of counts in cells, this work presents an advanced way of measuring it with unprecedented accuracy. Szapudi & Colombi identified the main sources of theoretical errors in extracting counts in cells from galaxy catalogs. One of these sources, termed as measurement error, stems from the fact that conventional methods use a finite number of sampling cells to estimate counts in cells. This effect can be circumvented by using an infinite number of cells. This paper presents an algorithm, which in practice achieves this goal; that is, it is equivalent to throwing an infinite number of sampling cells in finite time. The errors associated with sampling cells are completely eliminated by this procedure, which will be essential for the accurate analysis of future surveys.

  19. A Method for Correcting IMRT Optimizer Heterogeneity Dose Calculations

    International Nuclear Information System (INIS)

    Zacarias, Albert S.; Brown, Mellonie F.; Mills, Michael D.

    2010-01-01

    Radiation therapy treatment planning for volumes close to the patient's surface, in lung tissue and in the head and neck region, can be challenging for the planning system optimizer because of the complexity of the treatment and protected volumes, as well as striking heterogeneity corrections. Because it is often the goal of the planner to produce an isodose plan with uniform dose throughout the planning target volume (PTV), there is a need for improved planning optimization procedures for PTVs located in these anatomical regions. To illustrate such an improved procedure, we present a treatment planning case of a patient with a lung lesion located in the posterior right lung. The intensity-modulated radiation therapy (IMRT) plan generated using standard optimization procedures produced substantial dose nonuniformity across the tumor caused by the effect of lung tissue surrounding the tumor. We demonstrate a novel iterative method of dose correction performed on the initial IMRT plan to produce a more uniform dose distribution within the PTV. This optimization method corrected for the dose missing on the periphery of the PTV and reduced the maximum dose on the PTV to 106% from 120% on the representative IMRT plan.

  20. Calculation method for the seasonal performance of heat pump compact units and validation. Appendix

    Energy Technology Data Exchange (ETDEWEB)

    Wemhoener, C.; Dott, R.; Afjei, Th. [University of Applied Sciences Northwestern Switzerland, Institute of Energy in Buildings, Muttenz (Switzerland); Huber, H.; Helfenfinger, D.; Keller, P.; Furter, R. [University of Applied Sciences Lucerne (HTA), Test center HLKS, Horw (Switzerland)

    2007-02-15

    This appendix to a comprehensive final report for the Swiss Federal Office of Energy (SFOE) presents the results of tests made on compact heat pump units that have been developed for the heating of low energy consumption houses built to MINERGIE or MINERGIE-P standards. The tests on these units, which combine the functions of space heating, domestic hot water preparation and ventilation in one unit are presented and discussed. Test conditions are described; these cover ventilation, acoustic, hygiene and safety aspects. Detailed results from the two test objects - buildings built to MINERGIE and MINERGIE-P low energy consumption standards - are presented and discussed. The calculation methods used are examined and discussed.

  1. Calculation Of Recycle And Open Cycle Nuclear Fuel Cost Using Lagistase Method

    International Nuclear Information System (INIS)

    Djoko Birmano, Moch

    2002-01-01

    . To be presented the calculation of recycle and open cycle nuclear fuel cost for LWR type that have net power of 600 MWe. This calculation using LEGECOST method developed by IAEA which have characteristics,where i.e. money is stated in constant money (no inflation),discount rate is equalized with interest rate and not consider tax and depreciation.As a conclusion is that open cycle nuclear fuel cost more advantage because it is cheaper than recycle nuclear fuel cost. This is caused that at present, reprocessing process disadvantage because it has not found yet more efficient and cheaper method, besides price of fresh uranium is still cheap. In future, the cost of recycle nuclear fuel cycle will be more competitive toward the cost of open nuclear fuel cycle if is found technology of reprocessing process that more advance, efficient and cheap. Increase of Pu use for reactor fuel especially MOX type will rise Pu price that finally will decrease the cost of recycle nuclear fuel cycle

  2. On the question of calculation methods of phase diagrams

    International Nuclear Information System (INIS)

    Vasil'ev, M.V.

    1983-01-01

    The technique of determining interaction parameters of components of binary alloys is suggested. U-Mo and Cu-Al systems are used as example with the aid of experimental state diagrams. It is shown that the search for new regularities is necessary with the aim of analytical description of state diagrams and forecast of the shape of phase equilibria curves in real systems. Optimum combinations of experimental investigations with the aim of reliable determination of supporting points and forecasting possibilities of typical equations can considerably decrease the volume of experimental work when preparing state diagrams, in cases of repeated state diagrams of more reliable state diagrams with the application of more advanced methods of investigation. The translation of state diagrams from geometric to analytical language with the use of typical equations opens up new possibilities for establishing a compact information bank for state diagrams

  3. Performance of various mathematical methods for calculation of radioimmunoassay results

    International Nuclear Information System (INIS)

    Sandel, P.; Vogt, W.

    1977-01-01

    Interpolation and regression methods are available for computer aided determination of radioimmunological end results. We compared the performance of eight algorithms (weighted and unweighted linear logit-log regression, quadratic logit-log regression, Rodbards logistic model in the weighted and unweighted form, smoothing spline interpolation with a large and small smoothing factor and polygonal interpolation) on the basis of three radioimmunoassays with different reference curve characteristics (digoxin, estriol, human chorionic somatomammotropin = HCS). Great store was set by the accuracy of the approximation at the intermediate points on the curve, ie. those points that lie midway between two standard concentrations. These concentrations were obtained by weighing and inserted as unknown samples. In the case of digoxin and estriol the polygonal interpolation provided the best results while the weighted logit-log regression proved superior in the case of HCS. (orig.) [de

  4. Comparison of hardenability calculation methods of the heat-treatable constructional steels

    Energy Technology Data Exchange (ETDEWEB)

    Dobrzanski, L.A.; Sitek, W. [Division of Tool Materials and Computer Techniques in Metal Science, Silesian Technical University, Gliwice (Poland)

    1995-12-31

    Evaluation has been made of the consistency of calculation of the hardenability curves of the selected heat-treatable alloyed constructional steels with the experimental data. The study has been conducted basing on the analysis of present state of knowledge on hardenability calculation employing the neural network methods. Several calculation examples and comparison of the consistency of calculation methods employed are included. (author). 35 refs, 2 figs, 3 tabs.

  5. Different methods for calculation of LVEF: which is right?

    International Nuclear Information System (INIS)

    Blair, E.; McLean, R.; Dixson, H.

    1999-01-01

    Full text: Before the introduction of quantitative gated SPET (QGS) software, our routine method of determining left ventricular ejection fraction (LVEF) was the manual processing of gated heart pool studies (GHPS). The purpose of this preliminary study was to evaluate four methods of LVEF determination available in our private practice. We compared the LVEF obtained from manual GHPS (mGHPS) with that from automated GHPS (aGHPS), and that from both manual and automated QGS (mQGS and aQGS respectively) in 20 patients with a mean age of 63.5 years. All studies were analysed using standard ADAC computers and proprietary software. Two observers were used to determine mGHPS and mQGS, and the results were analysed using linear regression, Bland-Altman plots and visual analysis. The values determined by the two observers for the mGHPS and mQGS differed by an average of 1.15% and - 0.35% respectively and were strongly correlated (r = 0.95 and 0.94). For the automatic processing protocols (aGHPS and aQGS), there was a mean difference of 1.00% and a correlation of r = 0.63. The differences between mGHPS and aGHPS were greater than the differences between mQGS and aQGS. Comparing Observer 1's mGHPS and mQGS, a mean difference of 12.4% (range 2% to 24%), r=0.75. Comparing Observer 2's GHPS and QGS, a mean difference of 11.0% (range -11% to 22%), r = 0.66. Comparing the average mGHPS to aGHPS, a mean difference of 2.4% (range -8.5% to 12%), r = 0.88. Comparing the average mQGS to aQGS, a mean difference of -10.5% (range -18.5% to -5%), r = 0.96. From this study, we have found that the LVEF by mGHPS is substantially higher than mQGS, aGHPS and aQGS. Further investigation with a larger sample and different camera systems is needed

  6. Method of calculation overall equipment effectiveness in fertilizer factory

    Science.gov (United States)

    Siregar, I.; Muchtar, M. A.; Rahmat, R. F.; Andayani, U.; Nasution, T. H.; Sari, R. M.

    2018-02-01

    This research was conducted at a fertilizer company in Sumatra, where companies that produce fertilizers in large quantities to meet the needs of consumers. This company cannot be separated from issues related to the performance/effectiveness of the machinery and equipment. It can be seen from the engine that runs every day without a break resulted in not all of the quality of products in accordance with the quality standards set by the company. Therefore, to measure and improve the performance of the machine in the unit Plant Urea-1 as a whole then used method of Overall Equipment Effectiveness (OEE), which is one important element in the Total Productive Maintenance (TPM) to measure the effectiveness of the machine so that it can take measures to maintain that level. In July, August and September OEE values above the standard set at 85%. Meanwhile, in October, November and December have not reached the standard OEE values. The low value of OEE due to lack of time availability of machines for the production shut down due to the occurrence of the engine long enough so that the availability of reduced production time.

  7. Theories and calculation methods for regional objective ET

    Institute of Scientific and Technical Information of China (English)

    QIN DaYong; LO JinYan; LIU JiaHong; WANG MingNa

    2009-01-01

    The regional objective ET (Evapotranspiration) is a new concept in water resources research, which refers to the total amount of water that could be exhausted from a region in the form of vapor per year. The objective-ET based water resources management allocates water to different regions in terms of ET. It controls the water exhausted from a region to meet the objective ET. The regional objective ET must be adapted to fit the region's local available water resources. By improving the water utilization effi-ciency and reducing the unrecoverable water in the social water circle, it is saved so that water related production is maintained or even increased under the same water consumption conditions. Regional water balance is realized by rationally deploying the available water among different industries, adjusting industrial structures, and adopting new water-saving technologies, therefore to meeting the requirements for groundwater conservation, agricultural income stability, and avoiding environmental damages. Furthermore, water competition among various departments and industries (including envi-ronmental and ecological water use) may be avoided. This paper proposes an innovative definition of objective ET, and its principles, sub-index systems. Besides, a computational method for regional ob-jective ET is developed by combining the distributed hydrological model and the soil moisture model.

  8. Preconditioned Conjugate Gradient methods for low speed flow calculations

    Science.gov (United States)

    Ajmani, Kumud; Ng, Wing-Fai; Liou, Meng-Sing

    1993-01-01

    An investigation is conducted into the viability of using a generalized Conjugate Gradient-like method as an iterative solver to obtain steady-state solutions of very low-speed fluid flow problems. Low-speed flow at Mach 0.1 over a backward-facing step is chosen as a representative test problem. The unsteady form of the two dimensional, compressible Navier-Stokes equations are integrated in time using discrete time-steps. The Navier-Stokes equations are cast in an implicit, upwind finite-volume, flux split formulation. The new iterative solver is used to solve a linear system of equations at each step of the time-integration. Preconditioning techniques are used with the new solver to enhance the stability and the convergence rate of the solver and are found to be critical to the overall success of the solver. A study of various preconditioners reveals that a preconditioner based on the lower-upper (L-U)-successive symmetric over-relaxation iterative scheme is more efficient than a preconditioner based on incomplete L-U factorizations of the iteration matrix. The performance of the new preconditioned solver is compared with a conventional line Gauss-Seidel relaxation (LGSR) solver. Overall speed-up factors of 28 (in terms of global time-steps required to converge to a steady-state solution) and 20 (in terms of total CPU time on one processor of a CRAY-YMP) are found in favor of the new preconditioned solver, when compared with the LGSR solver.

  9. OCOPTR, Minimization of Nonlinear Function, Variable Metric Method, Derivative Calculation. DRVOCR, Minimization of Nonlinear Function, Variable Metric Method, Derivative Calculation

    International Nuclear Information System (INIS)

    Nazareth, J. L.

    1979-01-01

    1 - Description of problem or function: OCOPTR and DRVOCR are computer programs designed to find minima of non-linear differentiable functions f: R n →R with n dimensional domains. OCOPTR requires that the user only provide function values (i.e. it is a derivative-free routine). DRVOCR requires the user to supply both function and gradient information. 2 - Method of solution: OCOPTR and DRVOCR use the variable metric (or quasi-Newton) method of Davidon (1975). For OCOPTR, the derivatives are estimated by finite differences along a suitable set of linearly independent directions. For DRVOCR, the derivatives are user- supplied. Some features of the codes are the storage of the approximation to the inverse Hessian matrix in lower trapezoidal factored form and the use of an optimally-conditioned updating method. Linear equality constraints are permitted subject to the initial Hessian factor being chosen correctly. 3 - Restrictions on the complexity of the problem: The functions to which the routine is applied are assumed to be differentiable. The routine also requires (n 2 /2) + 0(n) storage locations where n is the problem dimension

  10. Calculations of time-of-flight aberrations in practical electrostatic electron lenses using the differential algebraic method

    International Nuclear Information System (INIS)

    Kang, Yongfeng; Zhao, Jingyi; Tang, Tiantong

    2013-01-01

    The high order time-of-flight (TOF) aberrations in a practical electrostatic electron lens are calculated using the differential algebraic (DA) method. The electrostatic fields of the electrostatic lens, which are calculated by the FEM methods, are in the form of discrete arrays. Thus, the proposed DA method is applicable for engineering designs, and programs are written to compute up to fifth order TOF aberrations of practical electrostatic electron lenses. An example is given, and TOF aberrations up to the fifth order are calculated. It is proven that the numerical results for the electrostatic fields in the form of discrete arrays have a good accuracy compared with the theoretical solutions. The accuracy is limited only by the accuracy of the numerical computation of the fields and the numerical computation algorithms for interpolation and integration. Finally, a practical electrostatic electron lens is analysed and discussed as an example.

  11. Efficient k⋅p method for the calculation of total energy and electronic density of states

    OpenAIRE

    Iannuzzi, Marcella; Parrinello, Michele

    2001-01-01

    An efficient method for calculating the electronic structure in large systems with a fully converged BZ sampling is presented. The method is based on a k.p-like approximation developed in the framework of the density functional perturbation theory. The reliability and efficiency of the method are demostrated in test calculations on Ar and Si supercells

  12. An Efficient Method for Electron-Atom Scattering Using Ab-initio Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yuan; Yang, Yonggang; Xiao, Liantuan; Jia, Suotang [Shanxi University, Taiyuan (China)

    2017-02-15

    We present an efficient method based on ab-initio calculations to investigate electron-atom scatterings. Those calculations profit from methods implemented in standard quantum chemistry programs. The new approach is applied to electron-helium scattering. The results are compared with experimental and other theoretical references to demonstrate the efficiency of our method.

  13. Development of approximate shielding calculation method for high energy cosmic radiation on LEO satellites

    International Nuclear Information System (INIS)

    Sin, M. W.; Kim, M. H.

    2002-01-01

    To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values

  14. Development of approximate shielding calculation method for high energy cosmic radiation on LEO satellites

    Energy Technology Data Exchange (ETDEWEB)

    Sin, M. W.; Kim, M. H. [Kyunghee Univ., Yongin (Korea, Republic of)

    2002-10-01

    To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values.

  15. Perturbation method for calculation of narrow-band impedance and trapped modes

    International Nuclear Information System (INIS)

    Heifets, S.A.

    1987-01-01

    An iterative method for calculation of the narrow-band impedance is described for a system with a small variation in boundary conditions, so that the variation can be considered as a perturbation. The results are compared with numeric calculations. The method is used to relate the origin of the trapped modes with the degeneracy of the spectrum of an unperturbed system. The method also can be applied to transverse impedance calculations. 6 refs., 6 figs., 1 tab

  16. Empirical pillar design methods review report: Final report

    International Nuclear Information System (INIS)

    1988-02-01

    This report summarizes and evaluates empirical pillar design methods that may be of use during the conceptual design of a high-level nuclear waste repository in salt. The methods are discussed according to category (i.e, main, submain, and panel pillars; barrier pillars; and shaft pillars). Of the 21 identified for main, submain, and panel pillars, one method, the Confined Core Method, is evaluated as being most appropriate for conceptual design. Five methods are considered potentially applicable. Of six methods identified for barrier pillars, one method based on the Load Transfer Distance concept is considered most appropriate for design. Based on the evaluation of 25 methods identified for shaft pillars, an approximate sizing criterion is proposed for use in conceptual design. Aspects of pillar performance relating to creep, ground deformation, interaction with roof and floor rock, and response to high temperature environments are not adequately addressed by existing empirical design methods. 152 refs., 22 figs., 14 tabs

  17. Calculation Method for Load Capacity of Urban Rail Transit Station considering Cascading Failure

    Directory of Open Access Journals (Sweden)

    Jiajun Huang

    2018-01-01

    Full Text Available The load capacity of urban rail transit station is of great significance to provide reference in station design and operation management. However, it is difficult to carry out quantitative calculation quickly and accurately due to the complex interaction among passenger behaviors, facility layout, and the limit capacity of single facility. In this paper, the association network of facilities is set up based on the analysis of passenger service chain in station. Then the concept of cascading failure is introduced to the dynamic calculation model of load capacity, which is established on the user-equilibrium allocation model. The solution algorithm is optimized with node attack strategy of complex network to effectively reduce the computational complexity. Finally, a case study of Lujiabang Road Station in Shanghai is carried out and compared with the simulation results of StaPass, verifying the feasibility of this approach. The proposed method can not only search for the bottleneck of capacity, but also help to trace the loading variation of facilities network in different scenarios, providing theoretical supports on passenger flow organization.

  18. New Method of Calculating a Multiplication by using the Generalized Bernstein-Vazirani Algorithm

    Science.gov (United States)

    Nagata, Koji; Nakamura, Tadao; Geurdes, Han; Batle, Josep; Abdalla, Soliman; Farouk, Ahmed

    2018-06-01

    We present a new method of more speedily calculating a multiplication by using the generalized Bernstein-Vazirani algorithm and many parallel quantum systems. Given the set of real values a1,a2,a3,\\ldots ,aN and a function g:bf {R}→ {0,1}, we shall determine the following values g(a1),g(a2),g(a3),\\ldots , g(aN) simultaneously. The speed of determining the values is shown to outperform the classical case by a factor of N. Next, we consider it as a number in binary representation; M 1 = ( g( a 1), g( a 2), g( a 3),…, g( a N )). By using M parallel quantum systems, we have M numbers in binary representation, simultaneously. The speed of obtaining the M numbers is shown to outperform the classical case by a factor of M. Finally, we calculate the product; M1× M2× \\cdots × MM. The speed of obtaining the product is shown to outperform the classical case by a factor of N × M.

  19. A CALCULATION METHOD OF TRANSIENT MODES OF ELECTRIC SHIPS’ PROPELLING ELECTRIC PLANTS

    Directory of Open Access Journals (Sweden)

    V. A. Yarovenko

    2017-12-01

    propulsion power plant according to the final result – according to the indicators characterizing the vessel and its maneuvering properties. The use of a system of dimensionless units provides a generality to the results obtained. Electric ships with equal values of dimensionless parameters will have correspondingly the same values (in relative units of maneuvering quality indicators. Practical value. The developed mathematical model and the research method constructed on its basis allow calculating the current values of the basic regime parameters of all the components of the ship’s propulsion complex. A mathematical apparatus for estimating the main indicators of the quality of electric ships’ maneuvering is proposed. There is an opportunity to improve the electric ships’ maneuvering characteristics by optimizing the operation of propulsion motors.

  20. An exact variational method to calculate rovibrational spectra of polyatomic molecules with large amplitude motion

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hua-Gen, E-mail: hgy@bnl.gov [Division of Chemistry, Department of Energy and Photon Sciences, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)

    2016-08-28

    We report a new full-dimensional variational algorithm to calculate rovibrational spectra of polyatomic molecules using an exact quantum mechanical Hamiltonian. The rovibrational Hamiltonian of system is derived in a set of orthogonal polyspherical coordinates in the body-fixed frame. It is expressed in an explicitly Hermitian form. The Hamiltonian has a universal formulation regardless of the choice of orthogonal polyspherical coordinates and the number of atoms in molecule, which is suitable for developing a general program to study the spectra of many polyatomic systems. An efficient coupled-state approach is also proposed to solve the eigenvalue problem of the Hamiltonian using a multi-layer Lanczos iterative diagonalization approach via a set of direct product basis set in three coordinate groups: radial coordinates, angular variables, and overall rotational angles. A simple set of symmetric top rotational functions is used for the overall rotation whereas a potential-optimized discrete variable representation method is employed in radial coordinates. A set of contracted vibrationally diabatic basis functions is adopted in internal angular variables. Those diabatic functions are first computed using a neural network iterative diagonalization method based on a reduced-dimension Hamiltonian but only once. The final rovibrational energies are computed using a modified Lanczos method for a given total angular momentum J, which is usually fast. Two numerical applications to CH{sub 4} and H{sub 2}CO are given, together with a comparison with previous results.

  1. An Improved Computational Method for the Calculation of Mixture Liquid-Vapor Critical Points

    Science.gov (United States)

    Dimitrakopoulos, Panagiotis; Jia, Wenlong; Li, Changjun

    2014-05-01

    Knowledge of critical points is important to determine the phase behavior of a mixture. This work proposes a reliable and accurate method in order to locate the liquid-vapor critical point of a given mixture. The theoretical model is developed from the rigorous definition of critical points, based on the SRK equation of state (SRK EoS) or alternatively, on the PR EoS. In order to solve the resulting system of nonlinear equations, an improved method is introduced into an existing Newton-Raphson algorithm, which can calculate all the variables simultaneously in each iteration step. The improvements mainly focus on the derivatives of the Jacobian matrix, on the convergence criteria, and on the damping coefficient. As a result, all equations and related conditions required for the computation of the scheme are illustrated in this paper. Finally, experimental data for the critical points of 44 mixtures are adopted in order to validate the method. For the SRK EoS, average absolute errors of the predicted critical-pressure and critical-temperature values are 123.82 kPa and 3.11 K, respectively, whereas the commercial software package Calsep PVTSIM's prediction errors are 131.02 kPa and 3.24 K. For the PR EoS, the two above mentioned average absolute errors are 129.32 kPa and 2.45 K, while the PVTSIM's errors are 137.24 kPa and 2.55 K, respectively.

  2. Study on application of green's function method in thermal stress rapid calculation

    International Nuclear Information System (INIS)

    Zhang Guihe; Duan Yuangang; Xu Xiao; Chen Rong

    2013-01-01

    This paper presents a quick and accuracy thermal stress calculation method, the Green's Function Method, which is a combination of finite element method and numerical algorithm method. Thermal stress calculation of Safe Injection Nozzle of Reactor Coolant Line of PWR plant is performed with Green's function method for heatup and cooldown thermal transients as a demonstration example, and the result is compared with finite element method to verify the rationality and accuracy of this method. The advantage and disadvantage of the Green's function method and the finite element method are also compared. (authors)

  3. Integrated Power Flow and Short Circuit Calculation Method for Distribution Network with Inverter Based Distributed Generation

    OpenAIRE

    Yang, Shan; Tong, Xiangqian

    2016-01-01

    Power flow calculation and short circuit calculation are the basis of theoretical research for distribution network with inverter based distributed generation. The similarity of equivalent model for inverter based distributed generation during normal and fault conditions of distribution network and the differences between power flow and short circuit calculation are analyzed in this paper. Then an integrated power flow and short circuit calculation method for distribution network with inverte...

  4. Comparison of the methods for calculating the interfacial heat transfer coefficient in hot stamping

    International Nuclear Information System (INIS)

    Zhao, Kunmin; Wang, Bin; Chang, Ying; Tang, Xinghui; Yan, Jianwen

    2015-01-01

    This paper presents a hot stamping experimentation and three methods for calculating the Interfacial Heat Transfer Coefficient (IHTC) of 22MnB5 boron steel. Comparison of the calculation results shows an average error of 7.5% for the heat balance method, 3.7% for the Beck's nonlinear inverse estimation method (the Beck's method), and 10.3% for the finite-element-analysis-based optimization method (the FEA method). The Beck's method is a robust and accurate method for identifying the IHTC in hot stamping applications. The numerical simulation using the IHTC identified by the Beck's method can predict the temperature field with a high accuracy. - Highlights: • A theoretical formula was derived for direct calculation of IHTC. • The Beck's method is a robust and accurate method for identifying IHTC. • Finite element method can be used to identify an overall equivalent IHTC

  5. Final report on the Copper Mountain conference on multigrid methods

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    The Copper Mountain Conference on Multigrid Methods was held on April 6-11, 1997. It took the same format used in the previous Copper Mountain Conferences on Multigrid Method conferences. Over 87 mathematicians from all over the world attended the meeting. 56 half-hour talks on current research topics were presented. Talks with similar content were organized into sessions. Session topics included: fluids; domain decomposition; iterative methods; basics; adaptive methods; non-linear filtering; CFD; applications; transport; algebraic solvers; supercomputing; and student paper winners.

  6. A combination of differential method and perturbation theory for the calculation of sensitivity coefficients

    International Nuclear Information System (INIS)

    Santos, Adimir dos; Borges, A.A.

    2000-01-01

    A new method for the calculation of sensitivity coefficients is developed. The new method is a combination of two methodologies used for calculating these coefficients, which are the differential and the generalized perturbation theory methods. The proposed method utilizes as integral parameter the average flux in an arbitrary region of the system. Thus, the sensitivity coefficient contains only the component corresponding to the neutron flux. To obtain the new sensitivity coefficient, the derivates of the integral parameter, φ(ξ), with respect to σ are calculated using the perturbation method and the functional derivates of this generic integral parameter with respect to σ and φ are calculated using the differential method. The new method merges the advantages of the differential and generalized perturbation theory methods and eliminates their disadvantages. (author)

  7. An Effective Method to Accurately Calculate the Phase Space Factors for β"-β"- Decay

    International Nuclear Information System (INIS)

    Horoi, Mihai; Neacsu, Andrei

    2016-01-01

    Accurate calculations of the electron phase space factors are necessary for reliable predictions of double-beta decay rates and for the analysis of the associated electron angular and energy distributions. We present an effective method to calculate these phase space factors that takes into account the distorted Coulomb field of the daughter nucleus, yet it allows one to easily calculate the phase space factors with good accuracy relative to the most exact methods available in the recent literature.

  8. Self-consistent field variational cellular method as applied to the band structure calculation of sodium

    International Nuclear Information System (INIS)

    Lino, A.T.; Takahashi, E.K.; Leite, J.R.; Ferraz, A.C.

    1988-01-01

    The band structure of metallic sodium is calculated, using for the first time the self-consistent field variational cellular method. In order to implement the self-consistency in the variational cellular theory, the crystal electronic charge density was calculated within the muffin-tin approximation. The comparison between our results and those derived from other calculations leads to the conclusion that the proposed self-consistent version of the variational cellular method is fast and accurate. (author) [pt

  9. PKI, Gamma Radiation Reactor Shielding Calculation by Point-Kernel Method

    International Nuclear Information System (INIS)

    Li Chunhuai; Zhang Liwu; Zhang Yuqin; Zhang Chuanxu; Niu Xihua

    1990-01-01

    1 - Description of program or function: This code calculates radiation shielding problem of gamma-ray in geometric space. 2 - Method of solution: PKI uses a point kernel integration technique, describes radiation shielding geometric space by using geometric space configuration method and coordinate conversion, and makes use of calculation result of reactor primary shielding and flow regularity in loop system for coolant

  10. New method of ionization energy calculation for two-electron ions

    International Nuclear Information System (INIS)

    Ershov, D.K.

    1997-01-01

    A new method for calculation of the ionization energy of two-electron ions is proposed. The method is based on the calculation of the energy of second electron interaction with the field of an one-electron ion the potential of which is well known

  11. Critical Values for Lawshe's Content Validity Ratio: Revisiting the Original Methods of Calculation

    Science.gov (United States)

    Ayre, Colin; Scally, Andrew John

    2014-01-01

    The content validity ratio originally proposed by Lawshe is widely used to quantify content validity and yet methods used to calculate the original critical values were never reported. Methods for original calculation of critical values are suggested along with tables of exact binomial probabilities.

  12. Comparison of Different Numerical Methods for Quality Factor Calculation of Nano and Micro Photonic Cavities

    DEFF Research Database (Denmark)

    Taghizadeh, Alireza; Mørk, Jesper; Chung, Il-Sug

    2014-01-01

    Four different numerical methods for calculating the quality factor and resonance wavelength of a nano or micro photonic cavity are compared. Good agreement was found for a wide range of quality factors. Advantages and limitations of the different methods are discussed.......Four different numerical methods for calculating the quality factor and resonance wavelength of a nano or micro photonic cavity are compared. Good agreement was found for a wide range of quality factors. Advantages and limitations of the different methods are discussed....

  13. A suggestion of a new method for the calculation of the coating thickness in continuous hot-dip galvanizing

    Energy Technology Data Exchange (ETDEWEB)

    Jo, C. M.; Kwon, Y. D.; Kwon, S. B. [Kyungpook National University, Daegu (Korea, Republic of); Kim, G. Y. [POSCO Technical Research laboratories, Gumgo-dong (Korea, Republic of)

    2011-11-15

    It is known that the distributions of the impinging pressure gradient and the shear stress at the strip surface play a decisive key role in the decision of the coating thickness in hot-dip galvanizing. So, to predict the exact coating thickness, it is essential that the distributions of the impinging wall jet pressure and the shear stress acting between the liquid film and jet stream are measured (or calculated) exactly for each specific coating condition. So far, to obtain the impinging wall jet pressure, it was assumed that the jet issuing from an air-knife is similar to the Hiemenz plane stagnation flow, and the wall shear stress could be predicted by an equation using the assumption of a non-negative Gaussian profile in impinging wall jet pressure in general, so that it cannot be reliable for some impinging wall jet regions and nozzle systems intrinsically. Nevertheless, one cannot find a suitable method to cope with the difficulties in measuring/calculating of the shear stress and the impinging wall jet pressure. Such a difficulty which will cause an inaccuracy in the coating thickness prediction. With these connections, in the present study, we suggest a new method named as a two-step calculation method to calculate the final coating thickness, which consists of the air jet analysis and coating thickness calculation. And, from the comparison of the results one may confirm the validation of the new suggested method.

  14. Polarizing matter and antimatter: A new method. Final report

    International Nuclear Information System (INIS)

    Onel, Y.

    1994-12-01

    Several years ago a self-polarization effect for stored (anti-)protons and ions was investigated theoretically. The effect is based on the well-known Stern-Gerlach effect in gradient fields. The aim of the ongoing measurements at the Indiana University Cyclotron Facility (IUCF) is to verify experimentally the various assumptions on which this effect is based. The final goal is to demonstrate this new polarization effect. The proposed effect could be a powerful tool to produce polarized stored hadron beams both in the low-energy range and at SSC and LHC energies. In this progress report the authors will describe the progress in three parts: (A) experimental work at IUCF Cooler Ring; (B) the extensive computer simulations of the spin stability for the IUCF Cooler Ring; and (C) theoretical studies

  15. Conventional method for the calculation of the global energy cost of buildings; Methode conventionnelle de calcul du cout global energetique des batiments

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-05-01

    A working group driven by Electricite de France (EdF), Chauffage Fioul and Gaz de France (GdF) companies has been built with the sustain of several building engineering companies in order to clarify the use of the method of calculation of the global energy cost of buildings. This global cost is an economical decision help criterion among others. This press kit presents, first, the content of the method (input data, calculation of annual expenses, calculation of the global energy cost, display of results and limitations of the method). Then it fully describes the method and its appendixes necessary for its implementation: economical and financial context, general data of the project in progress, environmental data, occupation and comfort level, variants, investment cost of energy systems, investment cost for the structure linked with the energy system, investment cost for other invariant elements of the structure, calculation of consumptions (space heating, hot water, ventilation), maintenance costs (energy systems, structure), operation and exploitation costs, tariffs and consumption costs and taxes, actualized global cost, annualized global cost, comparison between variants. The method is applied to a council building of 23 flats taken as an example. (J.S.)

  16. THORs Power Method for Hydrokinetic Devices - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    J. Turner Hunt; Joel Rumker

    2012-08-08

    Ocean current energy represents a vast untapped source of renewable energy that exists on the outer continental shelf areas of the 5 major continents. Ocean currents are unidirectional in nature and are perpetuated by thermal and salinity sea gradients, as well as coriolis forces imparted from the earth's rotation. This report details THORs Power Method, a breakthrough power control method that can provide dramatic increases to the capacity factor over and above existing marine hydrokinetic (MHK) devices employed in the extraction of energy from ocean currents. THORs Power Method represents a constant speed, variable depth operational method that continually locates the ocean current turbine at a depth at which the rated power of the generator is routinely achieved. Variable depth operation is achieved by using various vertical force effectors, including ballast tanks for variable weight, a hydrodynamic wing for variable lift or down force and drag flaps for variable vehicle drag forces.

  17. Environment-based pin-power reconstruction method for homogeneous core calculations

    International Nuclear Information System (INIS)

    Leroyer, H.; Brosselard, C.; Girardi, E.

    2012-01-01

    Core calculation schemes are usually based on a classical two-step approach associated with assembly and core calculations. During the first step, infinite lattice assemblies calculations relying on a fundamental mode approach are used to generate cross-sections libraries for PWRs core calculations. This fundamental mode hypothesis may be questioned when dealing with loading patterns involving several types of assemblies (UOX, MOX), burnable poisons, control rods and burn-up gradients. This paper proposes a calculation method able to take into account the heterogeneous environment of the assemblies when using homogeneous core calculations and an appropriate pin-power reconstruction. This methodology is applied to MOX assemblies, computed within an environment of UOX assemblies. The new environment-based pin-power reconstruction is then used on various clusters of 3x3 assemblies showing burn-up gradients and UOX/MOX interfaces, and compared to reference calculations performed with APOLLO-2. The results show that UOX/MOX interfaces are much better calculated with the environment-based calculation scheme when compared to the usual pin-power reconstruction method. The power peak is always better located and calculated with the environment-based pin-power reconstruction method on every cluster configuration studied. This study shows that taking into account the environment in transport calculations can significantly improve the pin-power reconstruction so far as it is consistent with the core loading pattern. (authors)

  18. Final Report: Symposium on Adaptive Methods for Partial Differential Equations

    Energy Technology Data Exchange (ETDEWEB)

    Pernice, Michael; Johnson, Christopher R.; Smith, Philip J.; Fogelson, Aaron

    1998-12-08

    Complex physical phenomena often include features that span a wide range of spatial and temporal scales. Accurate simulation of such phenomena can be difficult to obtain, and computations that are under-resolved can even exhibit spurious features. While it is possible to resolve small scale features by increasing the number of grid points, global grid refinement can quickly lead to problems that are intractable, even on the largest available computing facilities. These constraints are particularly severe for three dimensional problems that involve complex physics. One way to achieve the needed resolution is to refine the computational mesh locally, in only those regions where enhanced resolution is required. Adaptive solution methods concentrate computational effort in regions where it is most needed. These methods have been successfully applied to a wide variety of problems in computational science and engineering. Adaptive methods can be difficult to implement, prompting the development of tools and environments to facilitate their use. To ensure that the results of their efforts are useful, algorithm and tool developers must maintain close communication with application specialists. Conversely it remains difficult for application specialists who are unfamiliar with the methods to evaluate the trade-offs between the benefits of enhanced local resolution and the effort needed to implement an adaptive solution method.

  19. Approximated calculation of the vacuum wave function and vacuum energy of the LGT with RPA method

    International Nuclear Information System (INIS)

    Hui Ping

    2004-01-01

    The coupled cluster method is improved with the random phase approximation (RPA) to calculate vacuum wave function and vacuum energy of 2 + 1 - D SU(2) lattice gauge theory. In this calculating, the trial wave function composes of single-hollow graphs. The calculated results of vacuum wave functions show very good scaling behaviors at weak coupling region l/g 2 >1.2 from the third order to the sixth order, and the vacuum energy obtained with RPA method is lower than the vacuum energy obtained without RPA method, which means that this method is a more efficient one

  20. The Impact of Harmonics Calculation Methods on Power Quality Assessment in Wind Farms

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz Hubert; Hjerrild, Jesper; Bak, Claus Leth

    2010-01-01

    Different methods of calculating harmonics in measurements obtained from offshore wind farms are shown in this paper. Appropriate data processing methods are suggested for harmonics with different origin and nature. Enhancements of discrete Fourier transform application in order to reduce...... measurement data processing errors are proposed and compared with classical methods. Comparison of signal processing methods for harmonic studies is presented and application dependent on harmonics origin and nature recommended. Certain aspects related to magnitude and phase calculation in stationary...... measurement data are analysed and described. Qualitative indices of measurement data harmonic analysis in order to assess the calculation accuracy are suggested and used....

  1. Further development and data basis for safety and accident analyses of nuclear front end and back end facilities and actualization and revision of calculation methods for nuclear safety analyses. Final report; Weiterentwicklung von Methoden und Datengrundlagen zu Sicherheits- und Stoerfallanalysen fuer Anlagen der nuklearen Ver- und Entsorgung sowie Aktualisierung und Ueberpruefung von Rechenmethoden zu nuklearen Sicherheitsanalysen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kilger, Robert; Peters, Elisabeth; Sommer, Fabian; Moser, Eberhard-Franz; Kessen, Sven; Stuke, Maik

    2016-07-15

    This report briefly describes the activities carried out under the project 3613R03350 on the GRS ''Handbook on Accident Analysis for Nuclear Front and Back End Facilities'', and in detail the continuing work on the revision and updating of the GRS ''Handbook on Criticality'', which here focused on fissile systems with plutonium and {sup 233}U. The in previous projects started and ongoing literature study on innovative fuel concepts is continued. Also described are the review and qualification of computational methods by research and active benchmark participation, and the results of tracking the state of science and technology in the field of computational methods for criticality safety analysis. Special in-depth analyzes of selected criticality-relevant occurrences in the past are also documented.

  2. An algorithm of α-and γ-mode eigenvalue calculations by Monte Carlo method

    International Nuclear Information System (INIS)

    Yamamoto, Toshihiro; Miyoshi, Yoshinori

    2003-01-01

    A new algorithm for Monte Carlo calculation was developed to obtain α- and γ-mode eigenvalues. The α is a prompt neutron time decay constant measured in subcritical experiments, and the γ is a spatial decay constant measured in an exponential method for determining the subcriticality. This algorithm can be implemented into existing Monte Carlo eigenvalue calculation codes with minimum modifications. The algorithm was implemented into MCNP code and the performance of calculating the both mode eigenvalues were verified through comparison of the calculated eigenvalues with the ones obtained by fixed source calculations. (author)

  3. Virial-statistic method for calculation of atom and molecule energies

    International Nuclear Information System (INIS)

    Borisov, Yu.A.

    1977-01-01

    A virial-statistical method has been applied to the calculation of the atomization energies of the following molecules: Mo(CO) 6 , Cr(CO) 6 , Fe(CO) 5 , MnH(CO) 5 , CoH(CO) 4 , Ni(CO) 4 . The principles of this method are briefly presented. Calculation results are given for the individual contributions to the atomization energies together with the calculated and experimental atomization energies (D). For the Mo(CO) 6 complex Dsub(calc) = 1759 and Dsub(exp) = 1763 kcal/mole. Calculated and experimental combination heat values for carbonyl complexes are presented. These values are shown to be adequately consistent [ru

  4. A functional method for estimating DPA tallies in Monte Carlo calculations of Light Water Reactors

    International Nuclear Information System (INIS)

    Read, Edward A.; Oliveira, Cassiano R.E. de

    2011-01-01

    There has been a growing need in recent years for the development of methodology to calculate radiation damage factors, namely displacements per atom (dpa), of structural components for Light Water Reactors (LWRs). The aim of this paper is to discuss the development and implementation of a dpa method using Monte Carlo method for transport calculations. The capabilities of the Monte Carlo code Serpent such as Woodcock tracking and fuel depletion are assessed for radiation damage calculations and its capability demonstrated and compared to those of the Monte Carlo code MCNP for radiation damage calculations of a typical LWR configuration. (author)

  5. An accelerated hologram calculation using the wavefront recording plane method and wavelet transform

    Science.gov (United States)

    Arai, Daisuke; Shimobaba, Tomoyoshi; Nishitsuji, Takashi; Kakue, Takashi; Masuda, Nobuyuki; Ito, Tomoyoshi

    2017-06-01

    Fast hologram calculation methods are critical in real-time holography applications such as three-dimensional (3D) displays. We recently proposed a wavelet transform-based hologram calculation called WASABI. Even though WASABI can decrease the calculation time of a hologram from a point cloud, it increases the calculation time with increasing propagation distance. We also proposed a wavefront recoding plane (WRP) method. This is a two-step fast hologram calculation in which the first step calculates the superposition of light waves emitted from a point cloud in a virtual plane, and the second step performs a diffraction calculation from the virtual plane to the hologram plane. A drawback of the WRP method is in the first step when the point cloud has a large number of object points and/or a long distribution in the depth direction. In this paper, we propose a method combining WASABI and the WRP method in which the drawbacks of each can be complementarily solved. Using a consumer CPU, the proposed method succeeded in performing a hologram calculation with 2048 × 2048 pixels from a 3D object with one million points in approximately 0.4 s.

  6. Hamming method for solving the delayed neutron precursor concentration for reactivity calculation

    International Nuclear Information System (INIS)

    Díaz, Daniel Suescún; Ospina, Juan Felipe Flórez; Sarasty, Jesús Andrés Rodríguez

    2012-01-01

    Highlights: ► We present a new formulation to calculate the reactivity using the Hamming method. ► This method shows better accuracy than existing methods for reactivity calculation. ► The reactivity is calculated without limitation of the nuclear power form. ► The method can be implemented in reactivity meters with time step of up to 0.1 s. - Abstract: We propose a new method for numerically solving the inverse point kinetic equation for a nuclear reactor using the Hamming method, without requiring the nuclear power history and without using the Laplace transform. This new method converges with accuracy of order h 5 , where h is the step in the computation time. The procedure is validated for different forms of the nuclear power and with different time steps. The results indicate that this method has a better accuracy and lower computational effort compared with other conventional methods that use the nuclear power history.

  7. Cooling load calculation by the radiant time series method - effect of solar radiation models

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Alexandre M.S. [Universidade Estadual de Maringa (UEM), PR (Brazil)], E-mail: amscosta@uem.br

    2010-07-01

    In this work was analyzed numerically the effect of three different models for solar radiation on the cooling load calculated by the radiant time series' method. The solar radiation models implemented were clear sky, isotropic sky and anisotropic sky. The radiant time series' method (RTS) was proposed by ASHRAE (2001) for replacing the classical methods of cooling load calculation, such as TETD/TA. The method is based on computing the effect of space thermal energy storage on the instantaneous cooling load. The computing is carried out by splitting the heat gain components in convective and radiant parts. Following the radiant part is transformed using time series, which coefficients are a function of the construction type and heat gain (solar or non-solar). The transformed result is added to the convective part, giving the instantaneous cooling load. The method was applied for investigate the influence for an example room. The location used was - 23 degree S and 51 degree W and the day was 21 of January, a typical summer day in the southern hemisphere. The room was composed of two vertical walls with windows exposed to outdoors with azimuth angles equals to west and east directions. The output of the different models of solar radiation for the two walls in terms of direct and diffuse components as well heat gains were investigated. It was verified that the clear sky exhibited the less conservative (higher values) for the direct component of solar radiation, with the opposite trend for the diffuse component. For the heat gain, the clear sky gives the higher values, three times higher for the peek hours than the other models. Both isotropic and anisotropic models predicted similar magnitude for the heat gain. The same behavior was also verified for the cooling load. The effect of room thermal inertia was decreasing the cooling load during the peak hours. On the other hand the higher thermal inertia values are the greater for the non peak hours. The effect

  8. Transport theory calculation for a heterogeneous multi-assembly problem by characteristics method with direct neutron path linking technique

    International Nuclear Information System (INIS)

    Kosaka, Shinya; Saji, Etsuro

    2000-01-01

    A characteristics transport theory code, CHAPLET, has been developed for the purpose of making it practical to perform a whole LWR core calculation with the same level of calculational model and accuracy as that of an ordinary single assembly calculation. The characteristics routine employs the CACTUS algorithm for drawing ray tracing lines, which assists the two key features of the flux solution in the CHAPLET code. One is the direct neutron path linking (DNPL) technique which strictly connects angular fluxes at each assembly interface in the flux solution separated between assemblies. Another is to reduce the required memory storage by sharing the data related to ray tracing among assemblies with the same configuration. For faster computation, the coarse mesh rebalance (CMR) method and the Aitken method were incorporated in the code and the combined use of both methods showed the most promising acceleration performance among the trials. In addition, the parallelization of the flux solution was attempted, resulting in a significant reduction in the wall-clock time of the calculation. By all these efforts, coupled with the results of many verification studies, a whole LWR core heterogeneous transport theory calculation finally became practical. CHAPLET is thought to be a useful tool which can produce the reference solutions for analyses of an LWR (author)

  9. A finite element method for a time dependence soil-structure interactions calculations

    International Nuclear Information System (INIS)

    Ni, X.M.; Gantenbein, F.; Petit, M.

    1989-01-01

    The method which is proposed is based on a finite element modelisation for the soil and the structure and a time history calculation. It has been developed for plane and axisymmetric geometries. The principle of this method will be presented, then applications will be given, first to a linear calculation for which results will be compared to those obtained by standard methods. Then results for a non linear behavior will be described [fr

  10. Improvement of calculation method for temperature coefficient of HTTR by neutronics calculation code based on diffusion theory. Analysis for temperature coefficient by SRAC code system

    International Nuclear Information System (INIS)

    Goto, Minoru; Takamatsu, Kuniyoshi

    2007-03-01

    The HTTR temperature coefficients required for the core dynamics calculations had been calculated from the HTTR core calculation results by the diffusion code with which the corrections had been performed using the core calculation results by the Monte-Carlo code MVP. This calculation method for the temperature coefficients was considered to have some issues to be improved. Then, the calculation method was improved to obtain the temperature coefficients in which the corrections by the Monte-Carlo code were not required. Specifically, from the point of view of neutron spectrum calculated by lattice calculations, the lattice model was revised which had been used for the calculations of the temperature coefficients. The HTTR core calculations were performed by the diffusion code with the group constants which were generated by the lattice calculations with the improved lattice model. The core calculations and the lattice calculations were performed by the SRAC code system. The HTTR core dynamics calculation was performed with the temperature coefficient obtained from the core calculation results. In consequence, the core dynamics calculation result showed good agreement with the experimental data and the valid temperature coefficient could be calculated only by the diffusion code without the corrections by Monte-Carlo code. (author)

  11. The analysis of RPV fast neutron flux calculation for PWR with three-dimensional SN method

    International Nuclear Information System (INIS)

    Yang Shouhai; Chen Yixue; Wang Weijin; Shi Shengchun; Lu Daogang

    2011-01-01

    Discrete ordinates (S N ) method is one of the most widely used method for reactor pressure vessel (RPV) design. As the fast development of computer CPU speed and memory capacity and consummation of three-dimensional discrete-ordinates method, it is mature for 3-D S N method to be used to engineering design for nuclear facilities. This work was done specifically for PWR model, with the results of 3-D core neutron transport calculation by 3-D core calculation, 3-D RPV fast neutron flux distribution obtain by 3-D S N method were compared with gained by 1-D and 2-D S N method and the 3-D Monte Carlo (MC) method. In this paper, the application of three-dimensional S N method in calculating RPV fast neutron flux distribution for pressurized water reactor (PWR) is presented and discussed. (authors)

  12. Iterative resonance self-shielding methods using resonance integral table in heterogeneous transport lattice calculations

    International Nuclear Information System (INIS)

    Hong, Ser Gi; Kim, Kang-Seog

    2011-01-01

    This paper describes the iteration methods using resonance integral tables to estimate the effective resonance cross sections in heterogeneous transport lattice calculations. Basically, these methods have been devised to reduce an effort to convert resonance integral table into subgroup data to be used in the physical subgroup method. Since these methods do not use subgroup data but only use resonance integral tables directly, these methods do not include an error in converting resonance integral into subgroup data. The effective resonance cross sections are estimated iteratively for each resonance nuclide through the heterogeneous fixed source calculations for the whole problem domain to obtain the background cross sections. These methods have been implemented in the transport lattice code KARMA which uses the method of characteristics (MOC) to solve the transport equation. The computational results show that these iteration methods are quite promising in the practical transport lattice calculations.

  13. Calculating Effective Elastic Properties of Berea Sandstone Using Segmentation-less Method without Targets

    Science.gov (United States)

    Ikeda, K.; Goldfarb, E. J.; Tisato, N.

    2017-12-01

    Digital rock physics (DRP) allows performing common laboratory experiments on numerical models to estimate, for example, rock hydraulic permeability. The standard procedure of DRP involves turning a rock sample into a numerical array using X-ray micro computed tomography (micro-CT). Each element of the array bears a value proportional to the X-ray attenuation of the rock at the element (voxel). However, the traditional DRP methodology, which includes segmentation, over-predicts rock moduli by significant amounts (e.g., 100%). Recently, a new methodology - the segmentation-less approach - has been proposed leading to more accurate DRP estimate of elastic moduli. This new method is based on homogenization theory. Typically, segmentation-less approach requires calibration points from known density objects, known as targets. Not all micro-CT datasets have these reference points. Here, we describe how we perform segmentation- and target-less DRP to estimate elastic properties of rocks (i.e., elastic moduli), which are crucial parameters to perform subsurface modeling. We calculate the elastic properties of a Berea sandstone sample that was scanned at a resolution of 40 microns per voxel. We transformed the CT images into density matrices using polynomial fitting curve with four calibration points: the whole rock, the center of quartz grains, the center of iron oxide grains, and the center of air-filled volumes. The first calibration point is obtained by assigning the density of the whole rock to the average of all CT-numbers in the dataset. Then, we locate the center of each phase by finding local extrema point in the dataset. The average CT-numbers of these center points are assigned the density equal to either pristine minerals (quartz and iron oxide) or air. Next, density matrices are transformed to porosity and moduli matrices by means of an effective medium theory. Finally, effective static bulk and shear modulus are numerically calculated by using a Matlab code

  14. Convergence of spectral methods for nonlinear conservation laws. Final report

    International Nuclear Information System (INIS)

    Tadmor, E.

    1987-08-01

    The convergence of the Fourier method for scalar nonlinear conservation laws which exhibit spontaneous shock discontinuities is discussed. Numerical tests indicate that the convergence may (and in fact in some cases must) fail, with or without post-processing of the numerical solution. Instead, a new kind of spectrally accurate vanishing viscosity is introduced to augment the Fourier approximation of such nonlinear conservation laws. Using compensated compactness arguments, it is shown that this spectral viscosity prevents oscillations, and convergence to the unique entropy solution follows

  15. Cell homogenization methods for pin-by-pin core calculations tested in slab geometry

    International Nuclear Information System (INIS)

    Yamamoto, Akio; Kitamura, Yasunori; Yamane, Yoshihiro

    2004-01-01

    In this paper, performances of spatial homogenization methods for fuel or non-fuel cells are compared in slab geometry in order to facilitate pin-by-pin core calculations. Since the spatial homogenization methods were mainly developed for fuel assemblies, systematic study of their performance for the cell-level homogenization has not been carried out. Importance of cell-level homogenization is recently increasing since the pin-by-pin mesh core calculation in actual three-dimensional geometry, which is less approximate approach than current advanced nodal method, is getting feasible. Four homogenization methods were investigated in this paper; the flux-volume weighting, the generalized equivalence theory, the superhomogenization (SPH) method and the nonlinear iteration method. The last one, the nonlinear iteration method, was tested as the homogenization method for the first time. The calculations were carried out in simplified colorset assembly configurations of PWR, which are simulated by slab geometries, and homogenization performances were evaluated through comparison with the reference cell-heterogeneous calculations. The calculation results revealed that the generalized equivalence theory showed best performance. Though the nonlinear iteration method can significantly reduce homogenization error, its performance was not as good as that of the generalized equivalence theory. Through comparison of the results obtained by the generalized equivalence theory and the superhomogenization method, important byproduct was obtained; deficiency of the current superhomogenization method, which could be improved by incorporating the 'cell-level discontinuity factor between assemblies', was clarified

  16. A New Power Calculation Method for Single-Phase Grid-Connected Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede

    2013-01-01

    A new method to calculate average active power and reactive power for single-phase systems is proposed in this paper. It can be used in different applications where the output active power and reactive power need to be calculated accurately and fast. For example, a grid-connected photovoltaic...... system in low voltage ride through operation mode requires a power feedback for the power control loop. Commonly, a Discrete Fourier Transform (DFT) based power calculation method can be adopted in such systems. However, the DFT method introduces at least a one-cycle time delay. The new power calculation...... method, which is based on the adaptive filtering technique, can achieve a faster response. The performance of the proposed method is verified by experiments and demonstrated in a 1 kW single-phase grid-connected system operating under different conditions.Experimental results show the effectiveness...

  17. Calculation methods for SPF for heat pump systems for comparison, system choice and dimensioning

    Energy Technology Data Exchange (ETDEWEB)

    Nordman, Roger; Andersson, Kajsa; Axell, Monica; Lindahl, Markus

    2010-09-15

    In this project, results from field measurements of heat pumps have been collected and summarised. Also existing calculation methods have been compared and summarised. Analyses have been made on how the field measurements compare to existing calculation models for heat pumps Seasonal Performance Factor (SPF), and what deviations may depend on. Recommendations for new calculation models are proposed, which include combined systems (e.g. solar - HP), capacity controlled heat pumps and combined DHW and heating operation

  18. A grey diffusion acceleration method for time-dependent radiative transfer calculations: analysis and application

    International Nuclear Information System (INIS)

    Nowak, P.F.

    1993-01-01

    A grey diffusion acceleration method is presented and is shown by Fourier analysis and test calculations to be effective in accelerating radiative transfer calculations. The spectral radius is bounded by 0.9 for the continuous equations, but is significantly smaller for the discretized equations, especially in the optically thick regimes characteristic to radiation transport problems. The GDA method is more efficient than the multigroup DSA method because its slightly higher iteration count is more than offset by the much lower cost per iteration. A wide range of test calculations confirm the efficiency of GDA compared to multifrequency DSA. (orig.)

  19. Assessment of New Calculation Method for Toxicological Sums-of-Fractions for Hanford Tank Farm Wastes

    International Nuclear Information System (INIS)

    Mahoney, Lenna A.

    2006-01-01

    The toxicological source terms used for potential accident assessment in the Hanford Tank Farms DSA are based on toxicological sums-of-fractions (SOFs) that were calculated based on the Best Basis Inventory (BBI) from May 2002, using a method that depended on thermodynamic equilibrium calculations of the compositions of liquid and solid phases. The present report describes a simplified SOF-calculation method that is to be used in future toxicological updates and assessments and compares its results (for the 2002 BBI) to those of the old method.

  20. A fast dose calculation method based on table lookup for IMRT optimization

    International Nuclear Information System (INIS)

    Wu Qiuwen; Djajaputra, David; Lauterbach, Marc; Wu Yan; Mohan, Radhe

    2003-01-01

    This note describes a fast dose calculation method that can be used to speed up the optimization process in intensity-modulated radiotherapy (IMRT). Most iterative optimization algorithms in IMRT require a large number of dose calculations to achieve convergence and therefore the total amount of time needed for the IMRT planning can be substantially reduced by using a faster dose calculation method. The method that is described in this note relies on an accurate dose calculation engine that is used to calculate an approximate dose kernel for each beam used in the treatment plan. Once the kernel is computed and saved, subsequent dose calculations can be done rapidly by looking up this kernel. Inaccuracies due to the approximate nature of the kernel in this method can be reduced by performing scheduled kernel updates. This fast dose calculation method can be performed more than two orders of magnitude faster than the typical superposition/convolution methods and therefore is suitable for applications in which speed is critical, e.g., in an IMRT optimization that requires a simulated annealing optimization algorithm or in a practical IMRT beam-angle optimization system. (note)

  1. Calculation of neutron importance function in fissionable assemblies using Monte Carlo method

    International Nuclear Information System (INIS)

    Feghhi, S. A. H.; Afarideh, H.; Shahriari, M.

    2007-01-01

    The purpose of the present work is to develop an efficient solution method to calculate neutron importance function in fissionable assemblies for all criticality conditions, using Monte Carlo Method. The neutron importance function has a well important role in perturbation theory and reactor dynamic calculations. Usually this function can be determined by calculating adjoint flux through out solving the Adjoint weighted transport equation with deterministic methods. However, in complex geometries these calculations are very difficult. In this article, considering the capabilities of MCNP code in solving problems with complex geometries and its closeness to physical concepts, a comprehensive method based on physical concept of neutron importance has been introduced for calculating neutron importance function in sub-critical, critical and supercritical conditions. For this means a computer program has been developed. The results of the method has been benchmarked with ANISN code calculations in 1 and 2 group modes for simple geometries and their correctness has been approved for all three criticality conditions. Ultimately, the efficiency of the method for complex geometries has been shown by calculation of neutron importance in MNSR research reactor

  2. Cost comparison between Subterrene and current tunneling methods. Final report

    International Nuclear Information System (INIS)

    Bledsoe, J.D.; Hill, J.E.; Coon, R.F.

    1975-05-01

    A study was made to compare tunnel construction costs between the Subterrene tunneling system and methods currently in use. Three completed tunnels were selected for study cases to represent finished diameters ranging from 3.05 meters (10 feet) to 6.25 meters (20.5 feet). The study cases were normalized by deleting extraneous work and assigning labor, equipment, and materials costs for the Southern California area in 1974. Detailed cost estimates (shown in Appendix A) were then made for the three tunnels for baseline. A conceptual nuclear powered Subterrene tunneling machine (NSTM) was designed. It was assumed that NSTM's were available for each of the three baseline tunnels. Costs were estimated (shown in Appendix B) for the baseline tunnels driven by NSTM

  3. Methods for implementing revisions to emergency operating procedures. Final report

    International Nuclear Information System (INIS)

    Myers, L.B.; Bell, A.J.

    1984-05-01

    In response to the Three Mile Island (TMI) accident, the US Nuclear Regulatory Commission (NRC) has published the TMI Action Plan. The TMI Action Plan Item I.C.1 called for the upgrading of Emergency Operating Procedures (EOPs) at nuclear power plants. The program developed from this Action Plan item has resulted in utility efforts to: (1) revise EOPs; (2) train personnel in the use of the EOPs; and (3) implement the revised EOPs. The NRC supported the study presented in this report to identify factors which influence the effectiveness of training and implementation of revised EOPs. The NRC's major concern was the possible effects of negative transfer of training. The report includes a summary of existing methods for implementing revisions to procedures based on interviews of plant personnel, a review of the training literature applicable to the effect of previously learned procedures on the learning of and performance with revised procedures (i.e., negative transfer) and recommendations of methods and schedules for implementing revised EOPs. While the study found that the concern over negative transfer of training was not as great as anticipated, several recommendations were made. These include: (1) overtraining of operators to reduce the effect of observed negative transfer; and (2) implementation of the revised EOPs as soon as possible after training to minimize the time operators must rely upon the old EOPs after having been trained on the revised EOPs. The results of the study should be useful both to the utilities and the NRC in the development and review of EOP implementation programs

  4. Methods of calculating the post-closure performance of high-level waste repositories

    International Nuclear Information System (INIS)

    Ross, B.

    1989-02-01

    This report is intended as an overview of post-closure performance assessment methods for high-level radioactive waste repositories and is designed to give the reader a broad sense of the state of the art of this technology. As described here, ''the state of the art'' includes only what has been reported in report, journal, and conference proceedings literature through August 1987. There is a very large literature on the performance of high-level waste repositories. In order to make a review of this breadth manageable, its scope must be carefully defined. The essential principle followed is that only methods of calculating the long-term performance of waste repositories are described. The report is organized to reflect, in a generalized way, the logical order to steps that would be taken in a typical performance assessment. Chapter 2 describes ways of identifying scenarios and estimating their probabilities. Chapter 3 presents models used to determine the physical and chemical environment of a repository, including models of heat transfer, radiation, geochemistry, rock mechanics, brine migration, radiation effects on chemistry, and coupled processes. The next two chapters address the performance of specific barriers to release of radioactivity. Chapter 4 treats engineered barriers, including containers, waste forms, backfills around waste packages, shaft and borehole seals, and repository design features. Chapter 5 discusses natural barriers, including ground water systems and stability of salt formations. The final chapters address optics of general applicability to performance assessment models. Methods of sensitivity and uncertainty analysis are described in Chapter 6, and natural analogues of repositories are treated in Chapter 7. 473 refs., 19 figs., 2 tabs

  5. Methods of calculating the post-closure performance of high-level waste repositories

    Energy Technology Data Exchange (ETDEWEB)

    Ross, B. (ed.)

    1989-02-01

    This report is intended as an overview of post-closure performance assessment methods for high-level radioactive waste repositories and is designed to give the reader a broad sense of the state of the art of this technology. As described here, ''the state of the art'' includes only what has been reported in report, journal, and conference proceedings literature through August 1987. There is a very large literature on the performance of high-level waste repositories. In order to make a review of this breadth manageable, its scope must be carefully defined. The essential principle followed is that only methods of calculating the long-term performance of waste repositories are described. The report is organized to reflect, in a generalized way, the logical order to steps that would be taken in a typical performance assessment. Chapter 2 describes ways of identifying scenarios and estimating their probabilities. Chapter 3 presents models used to determine the physical and chemical environment of a repository, including models of heat transfer, radiation, geochemistry, rock mechanics, brine migration, radiation effects on chemistry, and coupled processes. The next two chapters address the performance of specific barriers to release of radioactivity. Chapter 4 treats engineered barriers, including containers, waste forms, backfills around waste packages, shaft and borehole seals, and repository design features. Chapter 5 discusses natural barriers, including ground water systems and stability of salt formations. The final chapters address optics of general applicability to performance assessment models. Methods of sensitivity and uncertainty analysis are described in Chapter 6, and natural analogues of repositories are treated in Chapter 7. 473 refs., 19 figs., 2 tabs.

  6. The ion exchange and its connection the industry II.- Calculation methods for installations

    International Nuclear Information System (INIS)

    Uriarte Hueda, A.; Lopez Perez, B.; Gutierrez Jodra, L.

    1960-01-01

    An exposure is made of calculation methods for ion exchange installations based on kinetic considerations and similarity with other unitary operations. Factors to be experimentally obtained as well as difficulties which may occur in its determination are also given. Calculation procedures most commonly used in industry are enclosed and explained with numerical resolution of a problem of water demineralization. (Author) 22 refs

  7. A Simple and Convenient Method of Multiple Linear Regression to Calculate Iodine Molecular Constants

    Science.gov (United States)

    Cooper, Paul D.

    2010-01-01

    A new procedure using a student-friendly least-squares multiple linear-regression technique utilizing a function within Microsoft Excel is described that enables students to calculate molecular constants from the vibronic spectrum of iodine. This method is advantageous pedagogically as it calculates molecular constants for ground and excited…

  8. A modified Gaussian integration method for thermal reaction rate calculation in U- and Pu-isotopes

    International Nuclear Information System (INIS)

    Bosevski, T.; Fredin, B.

    1966-01-01

    An advanced multi-group cell calculations a lot of data information is very often necessary, and hence the data administration will be elaborate, and the spectrum calculation will be time consuming. We think it is possible to reduce the necessary data information by using an effective reaction rate integration method well suited for U- and Pu-absorptions (author)

  9. Implantation of a new calculation method of fuel depletion in the CITHAM code

    International Nuclear Information System (INIS)

    Alvarenga, M.A.B.

    1985-01-01

    It is evaluated the accuracy of the linear aproximation method used in the CITHAN code to obtain the solution of depletion equations. Results are compared with the Benchmark problem. The convenience of depletion chain before criticality calculations is analysed. The depletion calculation was modified using linear combination technic of linear chains. (M.C.K.) [pt

  10. Projection methods for the calculation of incompressible or dilatable flows; Methodes de projection pour le calcul d'ecoulements incompressibles ou dilatables

    Energy Technology Data Exchange (ETDEWEB)

    Jobelin, M

    2006-10-15

    This thesis treats of time resolution methods for the Navier-Stokes equations. Based on the well-known projection method of Chorin and Temam, an original pressure correction method, named 'projection-penalty' is developed. Its specificity concerns the addition of a penalty term in the prediction step, which constrains the predicted velocity to fit with the mass balance. The precision improvements added by this method are demonstrated by some analysis results and by some numerical experiments of incompressible or dilatable flows. Finally, the potentialities offered by the use of the joint finite elements method in this type of fractionary step scheme is studied. Two applications are presented, one for local refinement purpose, the other for the resolution of a multi-physics problem. (J.S.)

  11. Wave packet methods for the direct calculation of energy-transfer moments in molecular collisions

    International Nuclear Information System (INIS)

    Bradley, K.S.; Schatz, G.C.; Balint-Kurti, G.G.

    1999-01-01

    The authors present a new wave packet based theory for the direct calculation of energy-transfer moments in molecular collision processes. This theory does not contain any explicit reference to final state information associated with the collision dynamics, thereby avoiding the need for determining vibration-rotation bound states (other than the initial state) for the molecules undergoing collision and also avoiding the calculation of state-to-state transition probabilities. The theory applies to energy-transfer moments of any order, and it generates moments for a wide range of translational energies in a single calculation. Two applications of the theory are made that demonstrate its viability; one is to collinear He + H 2 and the other to collinear He + CS 2 (with two active vibrational modes in CS 2 ). The results of these applications agree well with earlier results based on explicit calculation of transition probabilities

  12. Numerical calculation of acoustic radiation from band-vibrating structures via FEM/FAQP method

    Directory of Open Access Journals (Sweden)

    GAO Honglin

    2017-08-01

    Full Text Available The Finite Element Method (FEM combined with the Frequency Averaged Quadratic Pressure method (FAQP are used to calculate the acoustic radiation of structures excited in the frequency band. The surface particle velocity of stiffened cylindrical shells under frequency band excitation is calculated using finite element software, the normal vibration velocity is converted from the surface particle velocity to calculate the average energy source (frequency averaged across intensity, frequency averaged across pressure and frequency averaged across velocity, and the FAQP method is used to calculate the average sound pressure level within the bandwidth. The average sound pressure levels are then compared with the bandwidth using finite element and boundary element software, and the results show that FEM combined with FAQP is more suitable for high frequencies and can be used to calculate the average sound pressure level in the 1/3 octave band with good stability, presenting an alternative to applying frequency-by-frequency calculation and the average frequency process. The FEM/FAQP method can be used as a prediction method for calculating acoustic radiation while taking the randomness of vibration at medium and high frequencies into consideration.

  13. A modified method of calculating the lateral build-up ratio for small electron fields

    International Nuclear Information System (INIS)

    Tyner, E; McCavana, P; McClean, B

    2006-01-01

    This note outlines an improved method of calculating dose per monitor unit values for small electron fields using Khan's lateral build-up ratio (LBR). This modified method obtains the LBR directly from the ratio of measured, surface normalized, electron beam percentage depth dose curves. The LBR calculated using this modified method more accurately accounts for the change in lateral scatter with decreasing field size. The LBR is used along with Khan's dose per monitor unit formula to calculate dose per monitor unit values for a set of small fields. These calculated dose per monitor unit values are compared to measured values to within 3.5% for all circular fields and electron energies examined. The modified method was further tested using a small triangular field. A maximum difference of 4.8% was found. (note)

  14. A least squares calculational method: application to e±-H elastic scattering

    International Nuclear Information System (INIS)

    Das, J.N.; Chakraborty, S.

    1989-01-01

    The least squares calcualtional method proposed by Das has been applied for the e ± -H elastic scattering problems for intermediate energies. Some important conclusions are made on the basis of the calculation. (author). 7 refs ., 2 tabs

  15. Reactor theory and power reactors. 1. Calculational methods for reactors. 2. Reactor kinetics

    International Nuclear Information System (INIS)

    Henry, A.F.

    1980-01-01

    Various methods for calculation of neutron flux in power reactors are discussed. Some mathematical models used to describe transients in nuclear reactors and techniques for the reactor kinetics' relevant equations solution are also presented

  16. Improved method of generating bit reversed numbers for calculating fast fourier transform

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.

    Fast Fourier Transform (FFT) is an important tool required for signal processing in defence applications. This paper reports an improved method for generating bit reversed numbers needed in calculating FFT using radix-2. The refined algorithm takes...

  17. The adaptation of methods in multilayer optics for the calculation of specular neutron reflection

    International Nuclear Information System (INIS)

    Penfold, J.

    1988-10-01

    The adaptation of standard methods in multilayer optics to the calculation of specular neutron reflection is described. Their application is illustrated with examples which include a glass optical flat and a deuterated Langmuir-Blodgett film. (author)

  18. Research of coincidence method for calculation model of the specific detector

    Energy Technology Data Exchange (ETDEWEB)

    Guangchun, Hu; Suping, Liu; Jian, Gong [China Academy of Engineering Physics, Mianyang (China). Inst. of Nuclear Physics and Chemistry

    2003-07-01

    The physical size of specific detector is known normally, but production business is classified for some sizes that is concerned with the property of detector, such as the well diameter, well depth of detector and dead region. The surface source of even distribution and the sampling method of source particle isotropy sport have been established with the method of Monte Carlo, and gamma ray respond spectral with the {sup 152}Eu surface source been calculated. The experiment have been performed under the same conditions. Calculation and experiment results are compared with relative efficiency coincidence method and spectral similar degree coincidence method. According to comparison as a result, detector model is revised repeatedly to determine the calculation model of detector and to calculate efficiency of detector and spectra. (authors)

  19. Innovative methods for calculation of freeway travel time using limited data : executive summary report.

    Science.gov (United States)

    2008-08-01

    ODOTs policy for Dynamic Message Sign : utilization requires travel time(s) to be displayed as : a default message. The current method of : calculating travel time involves a workstation : operator estimating the travel time based upon : observati...

  20. Research on neutron noise analysis stochastic simulation method for α calculation

    International Nuclear Information System (INIS)

    Zhong Bin; Shen Huayun; She Ruogu; Zhu Shengdong; Xiao Gang

    2014-01-01

    The prompt decay constant α has significant application on the physical design and safety analysis in nuclear facilities. To overcome the difficulty of a value calculation with Monte-Carlo method, and improve the precision, a new method based on the neutron noise analysis technology was presented. This method employs the stochastic simulation and the theory of neutron noise analysis technology. Firstly, the evolution of stochastic neutron was simulated by discrete-events Monte-Carlo method based on the theory of generalized Semi-Markov process, then the neutron noise in detectors was solved from neutron signal. Secondly, the neutron noise analysis methods such as Rossia method, Feynman-α method, zero-probability method, and cross-correlation method were used to calculate a value. All of the parameters used in neutron noise analysis method were calculated based on auto-adaptive arithmetic. The a value from these methods accords with each other, the largest relative deviation is 7.9%, which proves the feasibility of a calculation method based on neutron noise analysis stochastic simulation. (authors)

  1. Calculation of isotopic mass and energy production by a matrix operator method

    International Nuclear Information System (INIS)

    Lee, C.E.

    1976-08-01

    The Volterra method of the multiplicative integral is used to determine the isotopic density, mass, and energy production in linear systems. The solution method, assumptions, and limitations are discussed. The method allows a rapid accurate calculation of the change in isotopic density, mass, and energy production independent of the magnitude of the time steps, production or decay rates, or flux levels

  2. The effective atomic numbers of some biomolecules calculated by two methods: A comparative study

    DEFF Research Database (Denmark)

    Manohara, S.R.; Hanagodimath, S.M.; Gerward, Leif

    2009-01-01

    The effective atomic numbers Z(eff) of some fatty acids and amino acids have been calculated by two numerical methods, a direct method and an interpolation method, in the energy range of 1 keV-20 MeV. The notion of Z(eff) is given a new meaning by using a modern database of photon interaction cro...

  3. Peculiarities of cyclotron magnetic system calculation with the finite difference method using two-dimensional approximation

    International Nuclear Information System (INIS)

    Shtromberger, N.L.

    1989-01-01

    To design a cyclotron magnetic system the legitimacy of two-dimensional approximations application is discussed. In all the calculations the finite difference method is used, and the linearization method with further use of the gradient conjugation method is used to solve the set of finite-difference equations. 3 refs.; 5 figs

  4. Calculation of one-loop anomalous dimensions by means of the background field method

    International Nuclear Information System (INIS)

    Morozov, A.Yu.

    1983-01-01

    The knowledge of propagators in background fields makes calculation of anomalous dimensions (AD) straightforward and brief. The paper illustrates this statement by calculation of AD of many spin-zero and one QCD operators up to the eighth dimension included. The method presented does not simplify calculations in case of four-quark operators, therefore these are not discussed. Together with calculational difficulties arising for operators with derivatives this limits capacities of the whole approach and leads to incompleteness of some mixing matrices found in the article

  5. Monte-Carlo Method Python Library for dose distribution Calculation in Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Randriantsizafy, R D; Ramanandraibe, M J [Madagascar Institut National des Sciences et Techniques Nucleaires, Antananarivo (Madagascar); Raboanary, R [Institut of astro and High-Energy Physics Madagascar, University of Antananarivo, Antananarivo (Madagascar)

    2007-07-01

    The Cs-137 Brachytherapy treatment is performed in Madagascar since 2005. Time treatment calculation for prescribed dose is made manually. Monte-Carlo Method Python library written at Madagascar INSTN is experimentally used to calculate the dose distribution on the tumour and around it. The first validation of the code was done by comparing the library curves with the Nucletron company curves. To reduce the duration of the calculation, a Grid of PC's is set up with listner patch run on each PC. The library will be used to modelize the dose distribution in the CT scan patient picture for individual and better accuracy time calculation for a prescribed dose.

  6. Monte-Carlo Method Python Library for dose distribution Calculation in Brachytherapy

    International Nuclear Information System (INIS)

    Randriantsizafy, R.D.; Ramanandraibe, M.J.; Raboanary, R.

    2007-01-01

    The Cs-137 Brachytherapy treatment is performed in Madagascar since 2005. Time treatment calculation for prescribed dose is made manually. Monte-Carlo Method Python library written at Madagascar INSTN is experimentally used to calculate the dose distribution on the tumour and around it. The first validation of the code was done by comparing the library curves with the Nucletron company curves. To reduce the duration of the calculation, a Grid of PC's is set up with listner patch run on each PC. The library will be used to modelize the dose distribution in the CT scan patient picture for individual and better accuracy time calculation for a prescribed dose.

  7. Comparison of the accuracy of three angiographic methods for calculating left ventricular volume measurement

    International Nuclear Information System (INIS)

    Hu Lin; Cui Wei; Shi Hanwen; Tian Yingping; Wang Weigang; Feng Yanguang; Huang Xueyan; Liu Zhisheng

    2003-01-01

    Objective: To compare the relative accuracy of three methods measuring left ventricular volume by X-ray ventriculography: single plane area-length method, biplane area-length method, and single-plane Simpson's method. Methods: Left ventricular casts were obtained within 24 hours after death from 12 persons who died from non-cardiac causes. The true left ventricular cast volume was measured by water displacement. The calculated volume of the casts was obtained with 3 angiographic methods, i.e., single-plane area-length method, biplane area-length method, and single-plane Simpson's method. Results: The actual average volume of left ventricular casts was (61.17±26.49) ml. The left ventricular volume was averagely (97.50±35.56) ml with single plane area-length method, (90.51±36.33) ml with biplane area-length method, and (65.00± 23.63) ml with single-plane Simpson's method. The left ventricular volumes calculated with single-plane and biplane area-length method were significantly larger than that the actual volumes (P 0.05). The left ventricular volumes calculated with single-plane and biplane area-length method were significantly larger than those calculated with single-plane Simpson's method (P 0.05). The over-estimation of left ventricular volume by single plane area-length method (36.34±17.98) ml and biplane area-length method (29.34±15.59) ml was more obvious than that calculated by single-plane Simpson's method (3.83±8.48) ml. Linear regression analysis showed that there was close correlations between left ventricular volumes calculated with single plane area-length method, biplane area-length method, Simpson's method and the true volume (all r>0.98). Conclusion: Single-plane Simpson's method is more accurate than single plane area-length method and biplane area-length method for left ventricular volume measurement; however, both the single-plane and biplane area-length methods could be used in clinical practice, especially in those imaging modality

  8. A study of the literature on nodal methods in reactor physics calculations

    International Nuclear Information System (INIS)

    Van de Wetering, T.F.H.

    1993-01-01

    During the last few decades several calculation methods have been developed for the three-dimensional analysis of a reactor core. A literature survey was carried out to gain insights in the starting points and method of operation of the advanced nodal methods. These methods are applied in reactor core analyses of large nuclear power reactors, because of their high computing speed. The so-called Nodal-Expansion method is described in detail

  9. LDRD Final Report: Adaptive Methods for Laser Plasma Simulation

    International Nuclear Information System (INIS)

    Dorr, M R; Garaizar, F X; Hittinger, J A

    2003-01-01

    The goal of this project was to investigate the utility of parallel adaptive mesh refinement (AMR) in the simulation of laser plasma interaction (LPI). The scope of work included the development of new numerical methods and parallel implementation strategies. The primary deliverables were (1) parallel adaptive algorithms to solve a system of equations combining plasma fluid and light propagation models, (2) a research code implementing these algorithms, and (3) an analysis of the performance of parallel AMR on LPI problems. The project accomplished these objectives. New algorithms were developed for the solution of a system of equations describing LPI. These algorithms were implemented in a new research code named ALPS (Adaptive Laser Plasma Simulator) that was used to test the effectiveness of the AMR algorithms on the Laboratory's large-scale computer platforms. The details of the algorithm and the results of the numerical tests were documented in an article published in the Journal of Computational Physics [2]. A principal conclusion of this investigation is that AMR is most effective for LPI systems that are ''hydrodynamically large'', i.e., problems requiring the simulation of a large plasma volume relative to the volume occupied by the laser light. Since the plasma-only regions require less resolution than the laser light, AMR enables the use of efficient meshes for such problems. In contrast, AMR is less effective for, say, a single highly filamented beam propagating through a phase plate, since the resulting speckle pattern may be too dense to adequately separate scales with a locally refined mesh. Ultimately, the gain to be expected from the use of AMR is highly problem-dependent. One class of problems investigated in this project involved a pair of laser beams crossing in a plasma flow. Under certain conditions, energy can be transferred from one beam to the other via a resonant interaction with an ion acoustic wave in the crossing region. AMR provides an

  10. Calculation method of the desiccant amount for the protection of packed electronic equipments and its comparison with other methods currently used

    International Nuclear Information System (INIS)

    Del Valle, J.C.; Guido, O.O.

    1982-01-01

    The silica gel characteristics and properties are reviewed from the viewpoint of its use as a desiccant under static conditions. There were developed two calculation methods of the desiccant amount required for the protection from moisture of electronic equipments packed into rigid synthetic foam containers, for a given period and with an adequate safety margin. Besides, MIL specifications methods applicable to this type of packages have been also included. The proposed method considers the depression due to the contraction of the inside air volume during the temperature decrease periods as the only cause of the water vapor ingress into the container, the moisture permeation by diffusion through the closed cell synthetic foams being negligible. Owing to the marked thermal inertia of the package material, the thermal amplitude inside the container is lower than the outside thermal amplitude; therefore the method includes the calculation of the former. The other method is based on a procedure applicable to large storage rooms, briefly described in the literature, and where the moisture entrance is due to the above mentioned cause. A test to verify the reliability of the estimation is proposed. Finally, the amount of silica gel required for the protection of an electronic equipment packed in a given container has been calculated by the aforementioned methods, and the results compared. The value found by the proposed method was over 30% lower than that obtained by the most adequate procedure described in the MIL specification. (author) [es

  11. Improved stiffness confinement method within the coarse mesh finite difference framework for efficient spatial kinetics calculation

    International Nuclear Information System (INIS)

    Park, Beom Woo; Joo, Han Gyu

    2015-01-01

    Highlights: • The stiffness confinement method is combined with multigroup CMFD with SENM nodal kernel. • The systematic methods for determining the shape and amplitude frequencies are established. • Eigenvalue problems instead of fixed source problems are solved in the transient calculation. • It is demonstrated that much larger time step sizes can be used with the SCM–CMFD method. - Abstract: An improved Stiffness Confinement Method (SCM) is formulated within the framework of the coarse mesh finite difference (CMFD) formulation for efficient multigroup spatial kinetics calculation. The algorithm for searching for the amplitude frequency that makes the dynamic eigenvalue unity is developed in a systematic way along with the methods for determining the shape and precursor frequencies. A nodal calculation scheme is established within the CMFD framework to incorporate the cross section changes due to thermal feedback and dynamic frequency update. The conditional nodal update scheme is employed such that the transient calculation is performed mostly with the CMFD formulation and the CMFD parameters are conditionally updated by intermittent nodal calculations. A quadratic representation of amplitude frequency is introduced as another improvement. The performance of the improved SCM within the CMFD framework is assessed by comparing the solution accuracy and computing times for the NEACRP control rod ejection benchmark problems with those obtained with the Crank–Nicholson method with exponential transform (CNET). It is demonstrated that the improved SCM is beneficial for large time step size calculations with stability and accuracy enhancement

  12. Methods of control of inaccuracy in calculation of nuclear power plant decommissioning parameters - 16383

    International Nuclear Information System (INIS)

    Ondra, Frantisek; Daniska, Vladimir; Rehak, Ivan; Necas, Vladimir

    2009-01-01

    The aim of the article is a development of analytical methodology for evaluation of input data inaccuracies impact on calculation of cost and other output decommissioning parameters. This methodology is based on analytical model calculations using the OMEGA code and taking into account the probability of input data inaccuracies occurrence also. To achieve about mentioned aim, the article identifies possible sources of input data inaccuracies and analyzes their level of impact on output parameters. Then the methodology for calculation of input parameters inaccuracies impact is developed, based on analytical model calculation. The model calculation takes into consideration output parameters impact on cost and other decommissioning output parameters in analytical way. The methodology used in model calculations is original, more over it implements the international standardized structure (IAEA, OECD/NEA, EC) [6] of decommissioning cost for the first time. A probabilistic occurrence of input data inaccuracies is taken into consideration and implemented in the methodology developed. A correction factors matrix for evaluation of input data inaccuracies impact on decommissioning output parameters is set up. The matrix contains parameters based on model calculations using the proposed methodology. Finally the methodology for application of correction factor matrix is proposed and tested; the methodology is used for calculation of contingency in the standardized structure which reflected the level of input data inaccuracies. The cost for individual decommissioning projects for common nuclear power plants are in the range 300 - 500 mil. EUR. Contingencies are from 10% to 30%, depending on the level of detailed during preparation of decommissioning projects. A implementation about mentioned methodology in the OMEGA code improves the accuracy of contingency. Consequently it makes calculated contingency more trustworthy and makes calculated decommissioning cost closer to reality

  13. Bending Moment Calculations for Piles Based on the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Yu-xin Jie

    2013-01-01

    Full Text Available Using the finite element analysis program ABAQUS, a series of calculations on a cantilever beam, pile, and sheet pile wall were made to investigate the bending moment computational methods. The analyses demonstrated that the shear locking is not significant for the passive pile embedded in soil. Therefore, higher-order elements are not always necessary in the computation. The number of grids across the pile section is important for bending moment calculated with stress and less significant for that calculated with displacement. Although computing bending moment with displacement requires fewer grid numbers across the pile section, it sometimes results in variation of the results. For displacement calculation, a pile row can be suitably represented by an equivalent sheet pile wall, whereas the resulting bending moments may be different. Calculated results of bending moment may differ greatly with different grid partitions and computational methods. Therefore, a comparison of results is necessary when performing the analysis.

  14. The calculations of small molecular conformation energy differences by density functional method

    Science.gov (United States)

    Topol, I. A.; Burt, S. K.

    1993-03-01

    The differences in the conformational energies for the gauche (G) and trans(T) conformers of 1,2-difluoroethane and for myo-and scyllo-conformer of inositol have been calculated by local density functional method (LDF approximation) with geometry optimization using different sets of calculation parameters. It is shown that in the contrast to Hartree—Fock methods, density functional calculations reproduce the correct sign and value of the gauche effect for 1,2-difluoroethane and energy difference for both conformers of inositol. The results of normal vibrational analysis for1,2-difluoroethane showed that harmonic frequencies calculated in LDF approximation agree with experimental data with the accuracy typical for scaled large basis set Hartree—Fock calculations.

  15. Transport calculation of medium-energy protons and neutrons by Monte Carlo method

    International Nuclear Information System (INIS)

    Ban, Syuuichi; Hirayama, Hideo; Katoh, Kazuaki.

    1978-09-01

    A Monte Carlo transport code, ARIES, has been developed for protons and neutrons at medium energy (25 -- 500 MeV). Nuclear data provided by R.G. Alsmiller, Jr. were used for the calculation. To simulate the cascade development in the medium, each generation was represented by a single weighted particle and an average number of emitted particles was used as the weight. Neutron fluxes were stored by the collisions density method. The cutoff energy was set to 25 MeV. Neutrons below the cutoff were stored to be used as the source for the low energy neutron transport calculation upon the discrete ordinates method. Then transport calculations were performed for both low energy neutrons (thermal -- 25 MeV) and secondary gamma-rays. Energy spectra of emitted neutrons were calculated and compared with those of published experimental and calculated results. The agreement was good for the incident particles of energy between 100 and 500 MeV. (author)

  16. Pellet by pellet neutron flux calculations coupled with nodal expansion method

    International Nuclear Information System (INIS)

    Aldo, Dall'Osso

    2003-01-01

    We present a technique whose aim is to replace 2-dimensional pin by pin de-homogenization, currently done in core reactor calculations with the nodal expansion method (NEM), by a 3-dimensional finite difference diffusion calculation. This fine calculation is performed as a zoom in each node taking as boundary conditions the results of the NEM calculations. The size of fine mesh is of the order of a fuel pellet. The coupling between fine and NEM calculations is realised by an albedo like boundary condition. Some examples are presented showing fine neutron flux shape near control rods or assembly grids. Other fine flux behaviour as the thermal flux rise in the fuel near the reflector is emphasised. In general the results show the interest of the method in conditions where the separability of radial and axial directions is not granted. (author)

  17. Nonlinear optimization method of ship floating condition calculation in wave based on vector

    Science.gov (United States)

    Ding, Ning; Yu, Jian-xing

    2014-08-01

    Ship floating condition in regular waves is calculated. New equations controlling any ship's floating condition are proposed by use of the vector operation. This form is a nonlinear optimization problem which can be solved using the penalty function method with constant coefficients. And the solving process is accelerated by dichotomy. During the solving process, the ship's displacement and buoyant centre have been calculated by the integration of the ship surface according to the waterline. The ship surface is described using an accumulative chord length theory in order to determine the displacement, the buoyancy center and the waterline. The draught forming the waterline at each station can be found out by calculating the intersection of the ship surface and the wave surface. The results of an example indicate that this method is exact and efficient. It can calculate the ship floating condition in regular waves as well as simplify the calculation and improve the computational efficiency and the precision of results.

  18. Non-parametric order statistics method applied to uncertainty propagation in fuel rod calculations

    International Nuclear Information System (INIS)

    Arimescu, V.E.; Heins, L.

    2001-01-01

    Advances in modeling fuel rod behavior and accumulations of adequate experimental data have made possible the introduction of quantitative methods to estimate the uncertainty of predictions made with best-estimate fuel rod codes. The uncertainty range of the input variables is characterized by a truncated distribution which is typically a normal, lognormal, or uniform distribution. While the distribution for fabrication parameters is defined to cover the design or fabrication tolerances, the distribution of modeling parameters is inferred from the experimental database consisting of separate effects tests and global tests. The final step of the methodology uses a Monte Carlo type of random sampling of all relevant input variables and performs best-estimate code calculations to propagate these uncertainties in order to evaluate the uncertainty range of outputs of interest for design analysis, such as internal rod pressure and fuel centerline temperature. The statistical method underlying this Monte Carlo sampling is non-parametric order statistics, which is perfectly suited to evaluate quantiles of populations with unknown distribution. The application of this method is straightforward in the case of one single fuel rod, when a 95/95 statement is applicable: 'with a probability of 95% and confidence level of 95% the values of output of interest are below a certain value'. Therefore, the 0.95-quantile is estimated for the distribution of all possible values of one fuel rod with a statistical confidence of 95%. On the other hand, a more elaborate procedure is required if all the fuel rods in the core are being analyzed. In this case, the aim is to evaluate the following global statement: with 95% confidence level, the expected number of fuel rods which are not exceeding a certain value is all the fuel rods in the core except only a few fuel rods. In both cases, the thresholds determined by the analysis should be below the safety acceptable design limit. An indirect

  19. Structural system reliability calculation using a probabilistic fault tree analysis method

    Science.gov (United States)

    Torng, T. Y.; Wu, Y.-T.; Millwater, H. R.

    1992-01-01

    The development of a new probabilistic fault tree analysis (PFTA) method for calculating structural system reliability is summarized. The proposed PFTA procedure includes: developing a fault tree to represent the complex structural system, constructing an approximation function for each bottom event, determining a dominant sampling sequence for all bottom events, and calculating the system reliability using an adaptive importance sampling method. PFTA is suitable for complicated structural problems that require computer-intensive computer calculations. A computer program has been developed to implement the PFTA.

  20. A method of paralleling computer calculation for two-dimensional kinetic plasma model

    International Nuclear Information System (INIS)

    Brazhnik, V.A.; Demchenko, V.V.; Dem'yanov, V.G.; D'yakov, V.E.; Ol'shanskij, V.V.; Panchenko, V.I.

    1987-01-01

    A method for parallel computer calculation and OSIRIS program complex realizing it and designed for numerical plasma simulation by the macroparticle method are described. The calculation can be carried out either with one or simultaneously with two computers BESM-6, that is provided by some package of interacting programs functioning in every computer. Program interaction in every computer is based on event techniques realized in OS DISPAK. Parallel computer calculation with two BESM-6 computers allows to accelerate the computation 1.5 times

  1. Lagrange polynomial interpolation method applied in the calculation of the J({xi},{beta}) function

    Energy Technology Data Exchange (ETDEWEB)

    Fraga, Vinicius Munhoz; Palma, Daniel Artur Pinheiro [Centro Federal de Educacao Tecnologica de Quimica de Nilopolis, RJ (Brazil)]. E-mails: munhoz.vf@gmail.com; dpalma@cefeteq.br; Martinez, Aquilino Senra [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE) (COPPE). Programa de Engenharia Nuclear]. E-mail: aquilino@lmp.ufrj.br

    2008-07-01

    The explicit dependence of the Doppler broadening function creates difficulties in the obtaining an analytical expression for J function . The objective of this paper is to present a method for the quick and accurate calculation of J function based on the recent advances in the calculation of the Doppler broadening function and on a systematic analysis of its integrand. The methodology proposed, of a semi-analytical nature, uses the Lagrange polynomial interpolation method and the Frobenius formulation in the calculation of Doppler broadening function . The results have proven satisfactory from the standpoint of accuracy and processing time. (author)

  2. Lagrange polynomial interpolation method applied in the calculation of the J(ξ,β) function

    International Nuclear Information System (INIS)

    Fraga, Vinicius Munhoz; Palma, Daniel Artur Pinheiro; Martinez, Aquilino Senra

    2008-01-01

    The explicit dependence of the Doppler broadening function creates difficulties in the obtaining an analytical expression for J function . The objective of this paper is to present a method for the quick and accurate calculation of J function based on the recent advances in the calculation of the Doppler broadening function and on a systematic analysis of its integrand. The methodology proposed, of a semi-analytical nature, uses the Lagrange polynomial interpolation method and the Frobenius formulation in the calculation of Doppler broadening function . The results have proven satisfactory from the standpoint of accuracy and processing time. (author)

  3. Calculation of large ion densities under HVdc transmission lines by the finite difference method

    International Nuclear Information System (INIS)

    Suda, Tomotaka; Sunaga, Yoshitaka

    1995-01-01

    A calculation method for large ion densities (charged aerosols) under HVdc transmission lines was developed considering both the charging mechanism of aerosols by small ions and the drifting process by wind. Large ion densities calculated by this method agreed well with the ones measured under the Shiobara HVdc test line on the lateral profiles at ground level up to about 70m downwind from the line. Measured values decreased more quickly than calculated ones farther downwind from the line. Considering the effect of point discharge from ground cover (earth corona) improved the agreement in the farther downwind region

  4. Calculation of mixed mode stress intensity factors using an alternating method

    International Nuclear Information System (INIS)

    Sakai, Takayuki

    1999-01-01

    In this study, mixed mode stress intensity factors (K I and K II ) of a square plate with a notch were calculated using a finite element alternating method. The obtained results were compared with the ones by a finite element method, and it was shown that the finite element alternating method can accurately estimate mixed mode stress intensity factors. Then, using this finite element alternating method, mixed mode stress intensity factors were calculated as changing the size and position of the notch, and its simplified equations were proposed. (author)

  5. A parallel orbital-updating based plane-wave basis method for electronic structure calculations

    International Nuclear Information System (INIS)

    Pan, Yan; Dai, Xiaoying; Gironcoli, Stefano de; Gong, Xin-Gao; Rignanese, Gian-Marco; Zhou, Aihui

    2017-01-01

    Highlights: • Propose three parallel orbital-updating based plane-wave basis methods for electronic structure calculations. • These new methods can avoid the generating of large scale eigenvalue problems and then reduce the computational cost. • These new methods allow for two-level parallelization which is particularly interesting for large scale parallelization. • Numerical experiments show that these new methods are reliable and efficient for large scale calculations on modern supercomputers. - Abstract: Motivated by the recently proposed parallel orbital-updating approach in real space method , we propose a parallel orbital-updating based plane-wave basis method for electronic structure calculations, for solving the corresponding eigenvalue problems. In addition, we propose two new modified parallel orbital-updating methods. Compared to the traditional plane-wave methods, our methods allow for two-level parallelization, which is particularly interesting for large scale parallelization. Numerical experiments show that these new methods are more reliable and efficient for large scale calculations on modern supercomputers.

  6. A method for calculating Bayesian uncertainties on internal doses resulting from complex occupational exposures

    International Nuclear Information System (INIS)

    Puncher, M.; Birchall, A.; Bull, R. K.

    2012-01-01

    Estimating uncertainties on doses from bioassay data is of interest in epidemiology studies that estimate cancer risk from occupational exposures to radionuclides. Bayesian methods provide a logical framework to calculate these uncertainties. However, occupational exposures often consist of many intakes, and this can make the Bayesian calculation computationally intractable. This paper describes a novel strategy for increasing the computational speed of the calculation by simplifying the intake pattern to a single composite intake, termed as complex intake regime (CIR). In order to assess whether this approximation is accurate and fast enough for practical purposes, the method is implemented by the Weighted Likelihood Monte Carlo Sampling (WeLMoS) method and evaluated by comparing its performance with a Markov Chain Monte Carlo (MCMC) method. The MCMC method gives the full solution (all intakes are independent), but is very computationally intensive to apply routinely. Posterior distributions of model parameter values, intakes and doses are calculated for a representative sample of plutonium workers from the United Kingdom Atomic Energy cohort using the WeLMoS method with the CIR and the MCMC method. The distributions are in good agreement: posterior means and Q 0.025 and Q 0.975 quantiles are typically within 20 %. Furthermore, the WeLMoS method using the CIR converges quickly: a typical case history takes around 10-20 min on a fast workstation, whereas the MCMC method took around 12-hr. The advantages and disadvantages of the method are discussed. (authors)

  7. Resampling Approach for Determination of the Method for Reference Interval Calculation in Clinical Laboratory Practice▿

    Science.gov (United States)

    Pavlov, Igor Y.; Wilson, Andrew R.; Delgado, Julio C.

    2010-01-01

    Reference intervals (RI) play a key role in clinical interpretation of laboratory test results. Numerous articles are devoted to analyzing and discussing various methods of RI determination. The two most widely used approaches are the parametric method, which assumes data normality, and a nonparametric, rank-based procedure. The decision about which method to use is usually made arbitrarily. The goal of this study was to demonstrate that using a resampling approach for the comparison of RI determination techniques could help researchers select the right procedure. Three methods of RI calculation—parametric, transformed parametric, and quantile-based bootstrapping—were applied to multiple random samples drawn from 81 values of complement factor B observations and from a computer-simulated normally distributed population. It was shown that differences in RI between legitimate methods could be up to 20% and even more. The transformed parametric method was found to be the best method for the calculation of RI of non-normally distributed factor B estimations, producing an unbiased RI and the lowest confidence limits and interquartile ranges. For a simulated Gaussian population, parametric calculations, as expected, were the best; quantile-based bootstrapping produced biased results at low sample sizes, and the transformed parametric method generated heavily biased RI. The resampling approach could help compare different RI calculation methods. An algorithm showing a resampling procedure for choosing the appropriate method for RI calculations is included. PMID:20554803

  8. Comparison of stress and total energy methods for calculation of elastic properties of semiconductors.

    Science.gov (United States)

    Caro, M A; Schulz, S; O'Reilly, E P

    2013-01-16

    We explore the calculation of the elastic properties of zinc-blende and wurtzite semiconductors using two different approaches: one based on stress and the other on total energy as a function of strain. The calculations are carried out within the framework of density functional theory in the local density approximation, with the plane wave-based package VASP. We use AlN as a test system, with some results also shown for selected other materials (C, Si, GaAs and GaN). Differences are found in convergence rate between the two methods, especially in low symmetry cases, where there is a much slower convergence for total energy calculations with respect to the number of plane waves and k points used. The stress method is observed to be more robust than the total energy method with respect to the residual error in the elastic constants calculated for different strain branches in the systems studied.

  9. Comparing Methods of Calculating Expected Annual Damage in Urban Pluvial Flood Risk Assessments

    DEFF Research Database (Denmark)

    Skovgård Olsen, Anders; Zhou, Qianqian; Linde, Jens Jørgen

    2015-01-01

    Estimating the expected annual damage (EAD) due to flooding in an urban area is of great interest for urban water managers and other stakeholders. It is a strong indicator for a given area showing how vulnerable it is to flood risk and how much can be gained by implementing e.g., climate change...... adaptation measures. This study identifies and compares three different methods for estimating the EAD based on unit costs of flooding of urban assets. One of these methods was used in previous studies and calculates the EAD based on a few extreme events by assuming a log-linear relationship between cost...... of an event and the corresponding return period. This method is compared to methods that are either more complicated or require more calculations. The choice of method by which the EAD is calculated appears to be of minor importance. At all three case study areas it seems more important that there is a shift...

  10. TORT/MCNP coupling method for the calculation of neutron flux around a core of BWR

    International Nuclear Information System (INIS)

    Kurosawa, M.

    2005-01-01

    For the analysis of BWR neutronics performance, accurate data are required for neutron flux distribution over the In-Reactor Pressure Vessel equipments taking into account the detailed geometrical arrangement. The TORT code can calculate neutron flux around a core of BWR in a three-dimensional geometry model, but has difficulties in fine geometrical modelling and lacks huge computer resource. On the other hand, the MCNP code enables the calculation of the neutron flux with a detailed geometry model, but requires very long sampling time to give enough number of particles. Therefore, a TORT/MCNP coupling method has been developed to eliminate the two problems mentioned above in each code. In this method, the TORT code calculates angular flux distribution on the core surface and the MCNP code calculates neutron spectrum at the points of interest using the flux distribution. The coupling method will be used as the DOT-DOMINO-MORSE code system. This TORT/MCNP coupling method was applied to calculate the neutron flux at points where induced radioactivity data were measured for 54 Mn and 60 Co and the radioactivity calculations based on the neutron flux obtained from the above method were compared with the measured data. (authors)

  11. TORT/MCNP coupling method for the calculation of neutron flux around a core of BWR.

    Science.gov (United States)

    Kurosawa, Masahiko

    2005-01-01

    For the analysis of BWR neutronics performance, accurate data are required for neutron flux distribution over the In-Reactor Pressure Vessel equipments taking into account the detailed geometrical arrangement. The TORT code can calculate neutron flux around a core of BWR in a three-dimensional geometry model, but has difficulties in fine geometrical modelling and lacks huge computer resource. On the other hand, the MCNP code enables the calculation of the neutron flux with a detailed geometry model, but requires very long sampling time to give enough number of particles. Therefore, a TORT/MCNP coupling method has been developed to eliminate the two problems mentioned above in each code. In this method, the TORT code calculates angular flux distribution on the core surface and the MCNP code calculates neutron spectrum at the points of interest using the flux distribution. The coupling method will be used as the DOT-DOMINO-MORSE code system. This TORT/MCNP coupling method was applied to calculate the neutron flux at points where induced radioactivity data were measured for 54Mn and 60Co and the radioactivity calculations based on the neutron flux obtained from the above method were compared with the measured data.

  12. Accuracy of cell calculation methods used for analysis of high conversion light water reactor lattice

    International Nuclear Information System (INIS)

    Jeong, Chang-Joon; Okumura, Keisuke; Ishiguro, Yukio; Tanaka, Ken-ichi

    1990-01-01

    Validation tests were made for the accuracy of cell calculation methods used in analyses of tight lattices of a mixed-oxide (MOX) fuel core in a high conversion light water reactor (HCLWR). A series of cell calculations was carried out for the lattices referred from an international HCLWR benchmark comparison, with emphasis placed on the resonance calculation methods; the NR, IR approximations, the collision probability method with ultra-fine energy group. Verification was also performed for the geometrical modelling; a hexagonal/cylindrical cell, and the boundary condition; mirror/white reflection. In the calculations, important reactor physics parameters, such as the neutron multiplication factor, the conversion ratio and the void coefficient, were evaluated using the above methods for various HCLWR lattices with different moderator to fuel volume ratios, fuel materials and fissile plutonium enrichments. The calculated results were compared with each other, and the accuracy and applicability of each method were clarified by comparison with continuous energy Monte Carlo calculations. It was verified that the accuracy of the IR approximation became worse when the neutron spectrum became harder. It was also concluded that the cylindrical cell model with the white boundary condition was not so suitable for MOX fuelled lattices, as for UO 2 fuelled lattices. (author)

  13. Point kernels and superposition methods for scatter dose calculations in brachytherapy

    International Nuclear Information System (INIS)

    Carlsson, A.K.

    2000-01-01

    Point kernels have been generated and applied for calculation of scatter dose distributions around monoenergetic point sources for photon energies ranging from 28 to 662 keV. Three different approaches for dose calculations have been compared: a single-kernel superposition method, a single-kernel superposition method where the point kernels are approximated as isotropic and a novel 'successive-scattering' superposition method for improved modelling of the dose from multiply scattered photons. An extended version of the EGS4 Monte Carlo code was used for generating the kernels and for benchmarking the absorbed dose distributions calculated with the superposition methods. It is shown that dose calculation by superposition at and below 100 keV can be simplified by using isotropic point kernels. Compared to the assumption of full in-scattering made by algorithms currently in clinical use, the single-kernel superposition method improves dose calculations in a half-phantom consisting of air and water. Further improvements are obtained using the successive-scattering superposition method, which reduces the overestimates of dose close to the phantom surface usually associated with kernel superposition methods at brachytherapy photon energies. It is also shown that scatter dose point kernels can be parametrized to biexponential functions, making them suitable for use with an effective implementation of the collapsed cone superposition algorithm. (author)

  14. A new method for calculating gas saturation of low-resistivity shale gas reservoirs

    Directory of Open Access Journals (Sweden)

    Jinyan Zhang

    2017-09-01

    Full Text Available The Jiaoshiba shale gas field is located in the Fuling area of the Sichuan Basin, with the Upper Ordovician Wufeng–Lower Silurian Longmaxi Fm as the pay zone. At the bottom of the pay zone, a high-quality shale gas reservoir about 20 m thick is generally developed with high organic contents and gas abundance, but its resistivity is relatively low. Accordingly, the gas saturation calculated by formulas (e.g. Archie using electric logging data is often much lower than the experiment-derived value. In this paper, a new method was presented for calculating gas saturation more accurately based on non-electric logging data. Firstly, the causes for the low resistivity of shale gas reservoirs in this area were analyzed. Then, the limitation of traditional methods for calculating gas saturation based on electric logging data was diagnosed, and the feasibility of the neutron–density porosity overlay method was illustrated. According to the response characteristics of neutron, density and other porosity logging in shale gas reservoirs, a model for calculating gas saturation of shale gas was established by core experimental calibration based on the density logging value, the density porosity and the difference between density porosity and neutron porosity, by means of multiple methods (e.g. the dual-porosity overlay method by optimizing the best overlay coefficient. This new method avoids the effect of low resistivity, and thus can provide normal calculated gas saturation of high-quality shale gas reservoirs. It works well in practical application. This new method provides a technical support for the calculation of shale gas reserves in this area. Keywords: Shale gas, Gas saturation, Low resistivity, Non-electric logging, Volume density, Compensated neutron, Overlay method, Reserves calculation, Sichuan Basin, Jiaoshiba shale gas field

  15. Kernel polynomial method for a nonorthogonal electronic-structure calculation of amorphous diamond

    International Nuclear Information System (INIS)

    Roeder, H.; Silver, R.N.; Drabold, D.A.; Dong, J.J.

    1997-01-01

    The Kernel polynomial method (KPM) has been successfully applied to tight-binding electronic-structure calculations as an O(N) method. Here we extend this method to nonorthogonal basis sets with a sparse overlap matrix S and a sparse Hamiltonian H. Since the KPM method utilizes matrix vector multiplications it is necessary to apply S -1 H onto a vector. The multiplication of S -1 is performed using a preconditioned conjugate-gradient method and does not involve the explicit inversion of S. Hence the method scales the same way as the original KPM method, i.e., O(N), although there is an overhead due to the additional conjugate-gradient part. We apply this method to a large scale electronic-structure calculation of amorphous diamond. copyright 1997 The American Physical Society

  16. Method for a reliable activation calculation of core components; Methode zur zuverlaessigen Berechnung von Aktivierungen in Kernbauteilen

    Energy Technology Data Exchange (ETDEWEB)

    Mispagel, T.; Phlippen, P.W.; Rose, J. [Wissenschaftlich-Technische Ingenieurberatung GmbH (WTI), Juelich (Germany)

    2013-07-01

    During nuclear power plant operation components and materials are exposed to the neutron flux from the reactor core and radionuclides are produced. After removal of the fuel elements the radioactivity of these radionuclides in the reactor pressure vessel and the core internals provide more than 99% of the activity of the power plant. For the transport, the interim storage and the final disposal of these radioactive components the radioactive inventories have to be decoded with respect to radiation and nuclides. The declaration of the nuclide and activity inventories requires a reliable calculation of neutron induced activation of reactor components. These activation calculations describe the pile-up of nuclides due to irradiation and due to the decay of nuclides. For an optimum usage of the activity capacities of the repository Konrad it is necessary to have a qualified calculation procedure that keeps the conservatism as low as possible.

  17. The Davidson Method as an alternative to power iterations for criticality calculations

    International Nuclear Information System (INIS)

    Subramanian, C.; Van Criekingen, S.; Heuveline, V.; Nataf, F.; Have, P.

    2011-01-01

    The Davidson method is implemented within the neutron transport core solver parafish to solve k-eigenvalue criticality transport problems. The parafish solver is based on domain decomposition, uses spherical harmonics (P_N method) for angular discretization, and nonconforming finite elements for spatial discretization. The Davidson method is compared to the traditional power iteration method in that context. Encouraging numerical results are obtained with both sequential and parallel calculations. (author)

  18. A superlinear iteration method for calculation of finite length journal bearing's static equilibrium position

    Science.gov (United States)

    Zhou, Wenjie; Wei, Xuesong; Wang, Leqin; Wu, Guangkuan

    2017-05-01

    Solving the static equilibrium position is one of the most important parts of dynamic coefficients calculation and further coupled calculation of rotor system. The main contribution of this study is testing the superlinear iteration convergence method-twofold secant method, for the determination of the static equilibrium position of journal bearing with finite length. Essentially, the Reynolds equation for stable motion is solved by the finite difference method and the inner pressure is obtained by the successive over-relaxation iterative method reinforced by the compound Simpson quadrature formula. The accuracy and efficiency of the twofold secant method are higher in comparison with the secant method and dichotomy. The total number of iterative steps required for the twofold secant method are about one-third of the secant method and less than one-eighth of dichotomy for the same equilibrium position. The calculations for equilibrium position and pressure distribution for different bearing length, clearance and rotating speed were done. In the results, the eccentricity presents linear inverse proportional relationship to the attitude angle. The influence of the bearing length, clearance and bearing radius on the load-carrying capacity was also investigated. The results illustrate that larger bearing length, larger radius and smaller clearance are good for the load-carrying capacity of journal bearing. The application of the twofold secant method can greatly reduce the computational time for calculation of the dynamic coefficients and dynamic characteristics of rotor-bearing system with a journal bearing of finite length.

  19. THE PARTICULARITIES OF THE COST CALCULATION METHOD ON COMMANDS IN FURNITURE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Felicia Sabou

    2014-10-01

    Full Text Available The paper present the importance of the method on commands in cost calculation and the particularities of the cost calculation method on commands in the furniture industry. This paper presents a hypotetical study on the method on commands, considering the observations made during 2013-2014, on how it is organized and managed accounts management using method on commands.By presenting this hypothetical model about the accounting in management accounting using the method on commands, the paper contributes to the correct application of this method in practice, specifically in management accounting in companies from the furniture industry. In my opinion the method on commands is an appropriate method for achieving management accounting for companies that have as main activity the production of furniture. When applying the method on commands in cost calculation and in management accounting, the companies must to consider the particularities of the cost calculation, in the furniture industry, like: technical and economic factors from this sector, the technical details of each command, the codification of the commands, planning materials and labor costs for each command, monitoring and recording production costs, registration of the direct costs, distribution of the indirect costs on commands, registration of the indirect costs and registration in management accounting.

  20. An assessment of methods of calculating sodium voiding reactivity in plutonium fuelled fast reactors

    International Nuclear Information System (INIS)

    Butland, A.T.D.; Simmons, W.N.; Stevenson, J.M.

    1979-01-01

    After a survey of the requirements an assessment of the accuracy of calculations of the sodium void effect using UK methods and data is made on the basis of the following work. First, the analysis of small and large sodium voids in the MOZART and Zebra 13 small (300 MW(E)) fast reactor mock-ups and the BIZET large fast reactor mock-ups, all of conventional design. The analysis was carried out using the UK FGL5 fine group nuclear data library, the MURAL cell code, whole reactor diffusion theory calculations of the neutron flux and perturbation theory methods. Exact perturbation theory was used in many cases, otherwise first order perturbation theory calculations were adjusted to give results equivalent to exact perturbation theory. Second, theoretical studies of some effects, including, the effects of extrapolating to fuel operating temperatures, fuel cycle and burn-up effects, and the heterogeneity effects of large fuelled subassemblies in pin geometry. Third, theoretical studies of approximations in the calculational methods including, the importance in the whole reactor calculation of the energy group structure and the spatial mesh, the importance of reactor material boundaries in the calculation of resonance shielding effects, and the use of neutron fluxes calculated using neutron diffusion theory rather than transport theory. (U.K.)

  1. Evaluation of radiation shielding performance in sea transport of radioactive material by using simple calculation method

    International Nuclear Information System (INIS)

    Odano, N.; Ohnishi, S.; Sawamura, H.; Tanaka, Y.; Nishimura, K.

    2004-01-01

    A modified code system based on the point kernel method was developed to use in evaluation of shielding performance for maritime transport of radioactive material. For evaluation of shielding performance accurately in the case of accident, it is required to preciously model the structure of transport casks and shipping vessel, and source term. To achieve accurate modelling of the geometry and source term condition, we aimed to develop the code system by using equivalent information regarding structure and source term used in the Monte Carlo calculation code, MCNP. Therefore, adding an option to use point kernel method to the existing Monte Carlo code, MCNP4C, the code system was developed. To verify the developed code system, dose rate distribution in an exclusive shipping vessel to transport the low level radioactive wastes were calculated by the developed code and the calculated results were compared with measurements and Monte Carlo calculations. It was confirmed that the developed simple calculation method can obtain calculation results very quickly with enough accuracy comparing with the Monte Carlo calculation code MCNP4C

  2. The simple analytical method for scattered radiation calculation in contrast X-ray diagnostic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, S; Pavlovic, R [Inst. of Nuclear Science Vinca, Belgrade (Yugoslavia). Radiation and Environmental Protection Lab.; Boreli, F [Fac. of Electrical Engineering, Belgrade (Yugoslavia)

    1996-12-31

    In realization of radiation protection measures for medical staff present during diagnostic procedures, the necessary condition is knowledge of the space - energy distributions of the scattered radiation from the patient. In this paper, the simple calculation procedure for the scattered radiation field of the actual diagnostic energies is presented. Starting from the single Compton scattering model and using the justified transformations the final equations in elementary form are derived. For numerical calculations the computer code ANGIO was created. The calculated results were confirmed by detailed dosimetric measurements of the scattered field around patient (the water phantom) in SSDL in the Institute of nuclear sciences `Vinca`, Belgrade. These results are good base for assessment of irradiation. The main irradiation source for the physician and the other members of the medical team is the back scattered radiation from patient - albedo. (author). 3 figs., 3 refs.

  3. Applications of Laplace transform methods to airfoil motion and stability calculations

    Science.gov (United States)

    Edwards, J. W.

    1979-01-01

    This paper reviews the development of generalized unsteady aerodynamic theory and presents a derivation of the generalized Possio integral equation. Numerical calculations resolve questions concerning subsonic indicial lift functions and demonstrate the generation of Kutta waves at high values of reduced frequency, subsonic Mach number, or both. The use of rational function approximations of unsteady aerodynamic loads in aeroelastic stability calculations is reviewed, and a reformulation of the matrix Pade approximation technique is given. Numerical examples of flutter boundary calculations for a wing which is to be flight tested are given. Finally, a simplified aerodynamic model of transonic flow is used to study the stability of an airfoil exposed to supersonic and subsonic flow regions.

  4. New sampling method in continuous energy Monte Carlo calculation for pebble bed reactors

    International Nuclear Information System (INIS)

    Murata, Isao; Takahashi, Akito; Mori, Takamasa; Nakagawa, Masayuki.

    1997-01-01

    A pebble bed reactor generally has double heterogeneity consisting of two kinds of spherical fuel element. In the core, there exist many fuel balls piled up randomly in a high packing fraction. And each fuel ball contains a lot of small fuel particles which are also distributed randomly. In this study, to realize precise neutron transport calculation of such reactors with the continuous energy Monte Carlo method, a new sampling method has been developed. The new method has been implemented in the general purpose Monte Carlo code MCNP to develop a modified version MCNP-BALL. This method was validated by calculating inventory of spherical fuel elements arranged successively by sampling during transport calculation and also by performing criticality calculations in ordered packing models. From the results, it was confirmed that the inventory of spherical fuel elements could be reproduced using MCNP-BALL within a sufficient accuracy of 0.2%. And the comparison of criticality calculations in ordered packing models between MCNP-BALL and the reference method shows excellent agreement in neutron spectrum as well as multiplication factor. MCNP-BALL enables us to analyze pebble bed type cores such as PROTEUS precisely with the continuous energy Monte Carlo method. (author)

  5. A new shielding calculation method for X-ray computed tomography regarding scattered radiation.

    Science.gov (United States)

    Watanabe, Hiroshi; Noto, Kimiya; Shohji, Tomokazu; Ogawa, Yasuyoshi; Fujibuchi, Toshioh; Yamaguchi, Ichiro; Hiraki, Hitoshi; Kida, Tetsuo; Sasanuma, Kazutoshi; Katsunuma, Yasushi; Nakano, Takurou; Horitsugi, Genki; Hosono, Makoto

    2017-06-01

    The goal of this study is to develop a more appropriate shielding calculation method for computed tomography (CT) in comparison with the Japanese conventional (JC) method and the National Council on Radiation Protection and Measurements (NCRP)-dose length product (DLP) method. Scattered dose distributions were measured in a CT room with 18 scanners (16 scanners in the case of the JC method) for one week during routine clinical use. The radiation doses were calculated for the same period using the JC and NCRP-DLP methods. The mean (NCRP-DLP-calculated dose)/(measured dose) ratios in each direction ranged from 1.7 ± 0.6 to 55 ± 24 (mean ± standard deviation). The NCRP-DLP method underestimated the dose at 3.4% in fewer shielding directions without the gantry and a subject, and the minimum (NCRP-DLP-calculated dose)/(measured dose) ratio was 0.6. The reduction factors were 0.036 ± 0.014 and 0.24 ± 0.061 for the gantry and couch directions, respectively. The (JC-calculated dose)/(measured dose) ratios ranged from 11 ± 8.7 to 404 ± 340. The air kerma scatter factor κ is expected to be twice as high as that calculated with the NCRP-DLP method and the reduction factors are expected to be 0.1 and 0.4 for the gantry and couch directions, respectively. We, therefore, propose a more appropriate method, the Japanese-DLP method, which resolves the issues of possible underestimation of the scattered radiation and overestimation of the reduction factors in the gantry and couch directions.

  6. Transport methods: general. 1. The Analytical Monte Carlo Method for Radiation Transport Calculations

    International Nuclear Information System (INIS)

    Martin, William R.; Brown, Forrest B.

    2001-01-01

    We present an alternative Monte Carlo method for solving the coupled equations of radiation transport and material energy. This method is based on incorporating the analytical solution to the material energy equation directly into the Monte Carlo simulation for the radiation intensity. This method, which we call the Analytical Monte Carlo (AMC) method, differs from the well known Implicit Monte Carlo (IMC) method of Fleck and Cummings because there is no discretization of the material energy equation since it is solved as a by-product of the Monte Carlo simulation of the transport equation. Our method also differs from the method recently proposed by Ahrens and Larsen since they use Monte Carlo to solve both equations, while we are solving only the radiation transport equation with Monte Carlo, albeit with effective sources and cross sections to represent the emission sources. Our method bears some similarity to a method developed and implemented by Carter and Forest nearly three decades ago, but there are substantive differences. We have implemented our method in a simple zero-dimensional Monte Carlo code to test the feasibility of the method, and the preliminary results are very promising, justifying further extension to more realistic geometries. (authors)

  7. The effective atomic numbers of some biomolecules calculated by two methods: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Manohara, S. R.; Hanagodimath, S. M.; Gerward, L. [Department of Physics, Gulbarga University, Gulbarga, Karnataka 585 106 (India); Department of Physics, Technical University of Denmark, Lyngby DK-2800 (Denmark)

    2009-01-15

    The effective atomic numbers Z{sub eff} of some fatty acids and amino acids have been calculated by two numerical methods, a direct method and an interpolation method, in the energy range of 1 keV-20 MeV. The notion of Z{sub eff} is given a new meaning by using a modern database of photon interaction cross sections (WinXCom). The results of the two methods are compared and discussed. It is shown that for all biomolecules the direct method gives larger values of Z{sub eff} than the interpolation method, in particular at low energies (1-100 keV) At medium energies (0.1-5 MeV), Z{sub eff} for both methods is about constant and equal to the mean atomic number of the material. Wherever possible, the calculated values of Z{sub eff} are compared with experimental data.

  8. The effective atomic numbers of some biomolecules calculated by two methods: A comparative study

    International Nuclear Information System (INIS)

    Manohara, S. R.; Hanagodimath, S. M.; Gerward, L.

    2009-01-01

    The effective atomic numbers Z eff of some fatty acids and amino acids have been calculated by two numerical methods, a direct method and an interpolation method, in the energy range of 1 keV-20 MeV. The notion of Z eff is given a new meaning by using a modern database of photon interaction cross sections (WinXCom). The results of the two methods are compared and discussed. It is shown that for all biomolecules the direct method gives larger values of Z eff than the interpolation method, in particular at low energies (1-100 keV) At medium energies (0.1-5 MeV), Z eff for both methods is about constant and equal to the mean atomic number of the material. Wherever possible, the calculated values of Z eff are compared with experimental data.

  9. A method of calculation on the airloading of vertical axis wind turbine

    Science.gov (United States)

    Azuma, A.; Kimura, S.

    A new method of analyzing the aerodynamic characteristics of the Darrieus Vertical-Axis Wind Turbine (VAWT) by applying the local circulation method is described. The validity of this method is confirmed by analyzing the air load acting on a curved blade. The azimuthwise variation of spanwise airloading, torque, and longitudinal forces are accurately calculated for a variety of operational conditions. The results are found to be in good agreement with experimental ones obtained elsewhere. It is concluded that the present approach can calculate the aerodynamic characteristics of the VAWT with much less computational time than that used by the free vortex model.

  10. Multiband method for resonance self-shielding calculation of fuel assembly in arbitrary geometries

    International Nuclear Information System (INIS)

    Huang Weibin; Wu Hongchun; Cao Liangzhi; Yang Weiyan

    2009-01-01

    A formula to calculate the multiband parameters is derived based on the multiband method. Adopting the method combining two-band and three-band, and based on the WIMSD4-69 library, a code named RESCAL is developed. The validation shows that the results of RESCAL code are well in accordance with MCNP's, and the numerical errors meet the practical requirement. Due to the limitation of WIMSD4 69-group library and the method adopted to calculate multiband parameters, the precision of RESCAL code is highly affected by the ratio of water to uranium. (authors)

  11. Perturbative versus Schwinger-propagator method for the calculation of amplitudes in a magnetic field

    International Nuclear Information System (INIS)

    Nieves, Jose F.; Pal, Palash B.

    2006-01-01

    We consider the calculation of amplitudes for processes that take place in a constant background magnetic field, first using the standard method for the calculation of an amplitude in an external field, and second utilizing the Schwinger propagator for charged particles in a magnetic field. We show that there are processes for which the Schwinger-propagator method does not yield the total amplitude. We explain why the two methods yield equivalent results in some cases and indicate when we can expect the equivalence to hold. We show these results in fairly general terms and illustrate them with specific examples as well

  12. Development of concept and neutronic calculation method for large LMFBR core

    International Nuclear Information System (INIS)

    Shirakata, K.; Ishikawa, M.; Ikegami, T.; Sanda, T.; Kaneto, K.; Kawashima, M.; Kaise, Y.; Shirakawa, M.; Hibi, K.

    1991-01-01

    Presented in this paper is the state of the art of reactor physics R and Ds for the development of concept and neutronic calculation method for large Liquid Metal Fast Breeder Reactor (LMFBR) core. Physics characteristics of concepts for mixed oxide (MOX) fueled large FBR core were investigated by a series of benchmark critical experiments. Next, an adequacy and accuracy of the current neutronic calculation method was assessed by the experiments analyses, and then neutronic prediction accuracies by the method were evaluated for physics characteristics of the large core. Concerns on core development were discussed in terms of neutronics. (author)

  13. Multiregion, multigroup collision probability method with white boundary condition for light water reactor thermalization calculations

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2005-01-01

    A multiregion, multigroup collision probability method with white boundary condition is developed for thermalization calculations of light water moderated reactors. Hydrogen scatterings are treated by Nelkin's kernel while scatterings from other nuclei are assumed to obey the free-gas scattering kernel. The isotropic return (white) boundary condition is applied directly by using the appropriate collision probabilities. Comparisons with alternate numerical methods show the validity of the present formulation. Comparisons with some experimental results indicate that the present formulation is capable of calculating disadvantage factors which are closer to the experimental results than alternative methods

  14. Performance of SOPPA-based methods in the calculation of vertical excitation energies and oscillator strengths

    DEFF Research Database (Denmark)

    Sauer, Stephan P. A.; Pitzner-Frydendahl, Henrik Frank; Buse, Mogens

    2015-01-01

    methods, the original SOPPA method as well as SOPPA(CCSD) and RPA(D) in the calculation of vertical electronic excitation energies and oscillator strengths is investigated for a large benchmark set of 28 medium-size molecules with 139 singlet and 71 triplet excited states. The results are compared...

  15. Calculation of U, Ra, Th and K contents in uranium ore by multiple linear regression method

    International Nuclear Information System (INIS)

    Lin Chao; Chen Yingqiang; Zhang Qingwen; Tan Fuwen; Peng Guanghui

    1991-01-01

    A multiple linear regression method was used to compute γ spectra of uranium ore samples and to calculate contents of U, Ra, Th, and K. In comparison with the inverse matrix method, its advantage is that no standard samples of pure U, Ra, Th and K are needed for obtaining response coefficients

  16. The calculation of deep levels in semiconductors by using a recursion method for super-cells

    International Nuclear Information System (INIS)

    Wong Yongliang.

    1987-01-01

    The paper presents the theory of deep levels in semiconductors, the super-cell approach to the theory of deep level impurities, the calculation of band structure by using the tight-binding method and the recursion method used to study the defects in the presence of lattice relaxation and extended defect complexes. 47 refs

  17. Heat production in growing pigs calculated according to the RQ and CN methods

    DEFF Research Database (Denmark)

    Christensen, K; Chwalibog, André; Henckel, S

    1988-01-01

    1. Heat production, calculated according to the respiratory quotient methods, HE(RQ), and the carbon nitrogen balance method, HE(CN), was compared using the results from a total of 326 balance trials with 56 castrated male pigs fed different dietary composition and variable feed levels during...

  18. Roundtrip matrix method for calculating the leaky resonant modes of open nanophotonic structures

    DEFF Research Database (Denmark)

    de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper

    2014-01-01

    We present a numerical method for calculating quasi-normal modes of open nanophotonic structures. The method is based on scattering matrices and a unity eigenvalue of the roundtrip matrix of an internal cavity, and we develop it in detail with electromagnetic fields expanded on Bloch modes...

  19. Evaluation of the streaming-matrix method for discrete-ordinates duct-streaming calculations

    International Nuclear Information System (INIS)

    Clark, B.A.; Urban, W.T.; Dudziak, D.J.

    1983-01-01

    A new deterministic streaming technique called the Streaming Matrix Hybrid Method (SMHM) is applied to two realistic duct-shielding problems. The results are compared to standard discrete-ordinates and Monte Carlo calculations. The SMHM shows promise as an alternative deterministic streaming method to standard discrete-ordinates

  20. A finite element method for calculating the 3-dimensional magnetic fields of cyclotron

    International Nuclear Information System (INIS)

    Zhao Xiaofeng

    1986-01-01

    A series of formula of the finite element method (scalar potential) for calculating the three-dimensional magnetic field of the main magnet of a sector focused cyclotron, and the realization method of the periodic boundary conditions in the code are given