Kochurov, B.P.
1980-01-01
Results of calculations of physical parameters characterizing the TRX, MIT and BETTIS critical assemblies obtained according to the program TRIFON are presented. The program TRIFON permits to calculate the space-energy neutron distribution in the multigroup approximation in a multizone cylindrical cell. Results of comparison of the TRX, BETTIS and MIT crytical assembly parameters with experimental data and calculational results according to the Monte Carlo method are presented as well. Deviations of the parameters are in the range of 1.5-2 of experimental errors. Data on the interference of uranium 238 levels in the resonant neutron absorption in the cell are given [ru
Calculation Of A Lattice Physics Parameter For SBWR Fuel Bundle Design
Sardjono, Y.
1996-01-01
The maximum power peaking factor for Nuclear Power Plant SBWR type is 1.5. The precision for that calculation is related with the result of unit cell analysis each rod in the fuel bundles. This analysis consist of lattice eigenvalue, lattice average diffusion cross section as well as relative power peaking factor in the fuel rod for each fuel bundles. The calculation by using TGBLA computer code which is based on the transport and 168 group diffusion theory. From this calculation can be concluded that the maximum relative power peaking factor is 1.304 and lower than design limit
Analysis of JSI TRIGA MARK II reactor physical parameters calculated with TRIPOLI and MCNP.
Henry, R; Tiselj, I; Snoj, L
2015-03-01
New computational model of the JSI TRIGA Mark II research reactor was built for TRIPOLI computer code and compared with existing MCNP code model. The same modelling assumptions were used in order to check the differences of the mathematical models of both Monte Carlo codes. Differences between the TRIPOLI and MCNP predictions of keff were up to 100pcm. Further validation was performed with analyses of the normalized reaction rates and computations of kinetic parameters for various core configurations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Physics parameter calculations for a Tandem Mirror Reactor with thermal barriers
Boghosian, B.M.; Lappa, D.A.; Logan, B.G.
1979-01-01
Thermal barriers are localized reductions in potential between the plugs and the central cell, which effectively insulate trapped plug electrons from the central cell electrons. By then applying electron heating in the plug, it is possible to obtain trapped electron temperatures that are much greater than those of the central cell electrons. This, in turn, effects an increase in the plug potential and central cell confinement with a concomitant decrease in plug density and injection power. Ions trapped in the barrier by collisions are removed by the injection of neutral beams directed inside the barrier cell loss cone; these beam neutrals convert trapped barrier ions to neutrals by charge exchange permitting their escape. We describe a zero-dimensional physics model for this type of reactor, and present some preliminary results for Q
Calculation of shielding parameters
Montoya Z, J.
1994-01-01
With the propose of reduce the hazard to radiation, exist three basic factors: a) time, the time to exposition to working person inside to area, from exist determined speed the doses, is proportional of the time permanence; b) distance, the reduce to doses is inverse square of the distance to exposition point; c) building, consist to interpose between source and exposition point to material. The main aspect development to the analysis of parameters distance and building. The analysis consist to development of the mathematical implicit, in the model of source radioactive, beginning with the geometry to source, distance to exposition source, and configuration building. In the final part was realize one comparative studied to calculus of parameters to blinding, employs two codes CPBGAM and MICROSHIELD, the first made as part to work thesis. The point source its a good approximation to any one real source, but in the majority of the time to propose analysis the spatial distribution of the source must realized in explicit way. The buildings calculus in volumetry's source can be approximate begin's of plan as source adaptations. It's important to have present that not only the building exist the exposition to the radiation, and the parameters time and distance plays an important paper too. (Author)
Faya, A.G.; Nakata, H.; Rodrigues, V.G.; Oosterkamp, W.J.
1974-01-01
The main variables for Obrigheim Reactor - KWO diffusion theory calculations, using the EREBUS code were defined. The variables under consideration were: mesh spacing for reactor description, time-step in burn-up calculation, and the temperature in both the moderator and the fuel. The best mesh spacing and time-step were defined considering the relative deviations and the computer time expended in each case. It has been verified that the error involved in the mean fuel temperature calculation (1317 0 K as given by SIEMENS and 1028 0 K as calculated by Dr. Penndorf) does not change substancially the calculation results
Quantization of physical parameters
Jackiw, R.; Massachusetts Inst. of Tech., Cambridge; Massachusetts Inst. of Tech., Cambridge
1984-01-01
Dynamical models are described with parameters (mass, coupling strengths) which must be quantized for quantum mechanical consistency. These and related topological ideas have physical application to phenomenological descriptions of high temperature and low energy quantum chromodynamics, to the nonrelativistic dynamics of magnetic monopoles, and to the quantum Hall effect. (author)
Application of nomograms to calculate radiography parameters
Voronin, S.A.; Orlov, K.P.; Petukhov, V.I.; Khomchenkov, Yu.F.; Meshalkin, I.A.; Grachev, A.V.; Akopov, V.'S.; Majorov, A.N.
1979-01-01
The method of calculation of radiography parameters with the help of nomograms usable for practical application under laboratory and industrial conditions, is proposed. Nomograms are developed for determining the following parameters: relative sensitivity, general non-definition of image, permissible difference of blackening density between the centre and edge of the picture (ΔD), picture contrast, focus distance, item thickness, radiation-physical parameter, dose build up factor, groove dimension and error. An experimental test has been carried out for evaluating the results, obtained with nomograms. Steel items from 25 to 79 mm thick have been subjected to testing 191 Ir has been used as a source. Comparison of calculation and experimental results has shown the discrepancy in sensitivity values, caused by ΔDsub(min) apriori index and the error, inherent in graphical plotting on a nomogram
Parameters calculation of shielding experiment
Gavazza, S.
1986-02-01
The radiation transport methodology comparing the calculated reactions and dose rates for neutrons and gama-rays, with experimental measurements obtained on iron shield, irradiated in the YAYOI reactor is evaluated. The ENDF/B-IV and VITAMIN-C libraries and the AMPX-II modular system, for cross sections generation collapsed by the ANISN code were used. The transport calculations were made using the DOT 3.5 code, adjusting the boundary iron shield source spectrum to the reactions and dose rates, measured at the beginning of shield. The neutron and gamma ray distributions calculated on the iron shield presented reasonable agreement with experimental measurements. An experimental arrangement using the IEA-R1 reactor to determine a shielding benchmark is proposed. (Author) [pt
Core physics calculation and analysis for SNRE
Xie Jiachun; Zhao Shouzhi; Jia Baoshan
2010-01-01
Five different precise calculation models have been set up for Small Nuclear Rocket Engine (SNRE) core based on MCNP code, and then the effective multiplication constant, drum control worth and power distribution were calculated. The results from different models indicate that the model in which elements are homogeneous could be used in the reactivity calculation, but a detailed description of elements have to be used in the element internal power distribution calculation. The results of physics parameters show that the basic characteristics of SNRE are reasonable. The drum control worth is sufficient. The power distribution is symmetrical and reasonable. All of the parameters can satisfy the design requirement. (authors)
Calculation of the neutron parameters of fast thermal reactor
Kukuleanu, V.; Mocioiu, D.; Drutse, E.; Konstantinesku, E.
1975-01-01
The system of neutron calculation for fast reactors is given. This system was used for estimation of physical parameters of fast thermal reactors investigated. The results obtained and different specific problems of the reactors of this type are described. (author)
Matausek, M; Spasojevic, D; Jovic, V; Marinkovic, N [Institut za Nuklearne Nauke Boris Kidric, Belgrade (Yugoslavia)
1988-07-01
The paper presents initial activities on creating a design concept of a new thermal research reactor, which should be built according to the research and development program in the field of nuclear fuel cycle technologies. For one possible type of such a reactor basic design parameters are specified and some preliminary results of nuclear, thermal and hydrodynamic design calculations are given. (author)
Characteristic parameters of drift chambers calculation
Duran, I.; Martinez-Laso, L.
1989-01-01
We present here the methods we used to analyse the characteristic parameters of drift chambers. The algorithms to calculate the electric potential in any point for any drift chamber geometry are presented. We include the description of the programs used to calculate the electric field, the drift paths, the drift velocity and the drift time. The results and the errors are discussed. (Author) 7 refs
Neutronic parameters calculations of a CANDU reactor
Zamonsky, G.
1991-01-01
Neutronic calculations that reproduce in a simplified way some aspects of a CANDU reactor design were performed. Starting from some prefixed reactor parameters, cylindrical and uniform iron adjuster rods were designed. An appropriate refueling scheme was established, defininig in a 2 zones model their dimensions and exit burnups. The calculations have been done using the codes WIMS-D4 (cell), SNOD (reactivity device simulations) and PUMA (reactor). Comparing with similar calculations done with codes and models usually employed for CANDU design, it is concluded that the models and methods used are appropriate. (Author) [es
WIPP Compliance Certification Application calculations parameters. Part 1: Parameter development
Howarth, S.M.
1997-01-01
The Waste Isolation Pilot Plant (WIPP) in southeast New Mexico has been studied as a transuranic waste repository for the past 23 years. During this time, an extensive site characterization, design, construction, and experimental program was completed, which provided in-depth understanding of the dominant processes that are most likely to influence the containment of radionuclides for 10,000 years. Nearly 1,500 parameters were developed using information gathered from this program; the parameters were input to numerical models for WIPP Compliance Certification Application (CCA) Performance Assessment (PA) calculations. The CCA probabilistic codes frequently require input values that define a statistical distribution for each parameter. Developing parameter distributions begins with the assignment of an appropriate distribution type, which is dependent on the type, magnitude, and volume of data or information available. The development of the parameter distribution values may require interpretation or statistical analysis of raw data, combining raw data with literature values, scaling of lab or field data to fit code grid mesh sizes, or other transformation. Parameter development and documentation of the development process were very complicated, especially for those parameters based on empirical data; they required the integration of information from Sandia National Laboratories (SNL) code sponsors, parameter task leaders (PTLs), performance assessment analysts (PAAs), and experimental principal investigators (PIs). This paper, Part 1 of two parts, contains a discussion of the parameter development process, roles and responsibilities, and lessons learned. Part 2 will discuss parameter documentation, traceability and retrievability, and lessons learned from related audits and reviews
Calculation of Optical Parameters of Liquid Crystals
Kumar, A.
2007-12-01
Validation of a modified four-parameter model describing temperature effect on liquid crystal refractive indices is being reported in the present article. This model is based upon the Vuks equation. Experimental data of ordinary and extraordinary refractive indices for two liquid crystal samples MLC-9200-000 and MLC-6608 are used to validate the above-mentioned theoretical model. Using these experimental data, birefringence, order parameter, normalized polarizabilities, and the temperature gradient of refractive indices are determined. Two methods: directly using birefringence measurements and using Haller's extrapolation procedure are adopted for the determination of order parameter. Both approches of order parameter calculation are compared. The temperature dependences of all these parameters are discussed. A close agreement between theory and experiment is obtained.
Calculation of Kinetic Parameters of TRIGA Reactor
Snoj, Luka; Kavcic, Andrej; Zerovnik, Gasper; Ravnik, Matjaz
2008-01-01
Modern Monte Carlo transport codes in combination of fast computer clusters enable very accurate calculations of the most important reactor kinetic parameters. Such are the effective delayed neutron fraction, β eff , and mean neutron generation time, Λ. We calculated the β eff and Λ for various realistic and hypothetical annular TRIGA Mark II cores with different types and amount of fuel. It can be observed that the effective delayed neutron fraction strongly depends on the number of fuel elements in the core or on the core size. E.g., for 12 wt. % uranium standard fuel with 20 % enrichment, β eff varies from 0.0080 for a small core (43 fuel rods) to 0.0075 for a full core (90 fuel rods). It is interesting to note that calculated value of β eff strongly depends also on the delayed neutron nuclear data set used in calculations. The prompt neutron life-time mainly depends on the amount (due to either content or enrichment) of 235 U in the fuel as it is approximately inversely proportional to the average absorption cross-section of the fuel. E.g., it varies from 28 μs for 30 wt. % uranium content fuelled core to 48 μs for 8.5 wt. % uranium content LEU fuelled core. The results are especially important for pulse mode operation and analysis of the pulses. (authors)
National Oceanic and Atmospheric Administration, Department of Commerce — The document presents the methods, formulas and citations used by the BNDO to process physical, chemical, and biological data for deep hydrology including...
Nuclear Data Processing for Reactor Physics Calculation
Suwoto; Zuhair; Pandiangan, Tumpal
2003-01-01
Nuclear data processing for reactor physics calculation has been done. Raw nuclear data cross-sections on file ENDF should be prepared and processed before it used in neutronic calculation. The processing code system such as NJOY-PC code has been used from linearization of nuclear cross-sections data and background contribution of resonance parameter (MF2) using RECONR module (0K) with energy range from 10 -5 to 10 7 eV. Afterward, the neutron cross-sections data should be processed and broadened to desire temperature (i.e. 293K) by using BROADR module. The Grouper and Therma modules will be applied for multi-groups calculation which suitable for WIMS/D4 (69 groups) and thermalization of nuclear constants. The final stage of processing nuclear cross-sections is updating WIMS/D4 library. The WIMSR module in NJOY-PC and WILLIE code will be applied in this stage. The evaluated nuclear data file, especially for 1 H 1 isotope, was taken from JENDL-3.2 and ENDF/B-VI for preliminary study. The results of nuclear data processing 1 H 1 shows that the old-WIMS (WIMS-lama) library have much discrepancies comparing with JENDL-3.2 or ENDF/B-VI files, especially in energy around 5 keV
Calculation of the ceramics Weibull parameters
Fuis, Vladimír; Návrat, Tomáš
2011-01-01
Roč. 58, - (2011), s. 642-647 ISSN 2010-376X. [International Conference on Bioinformatics and Biomedicine 2011. Bali, 26.10.2011-28.10.2011] Institutional research plan: CEZ:AV0Z20760514 Keywords : biomaterial parameters * Weibull statistics * ceramics Subject RIV: BO - Biophysics http://www.waset.org/journals/waset/v58/v58-132.pdf
Reactor physics calculations on HTR type configurations
Klippel, H.T.; Hogenbirk, A.; Stad, R.C.L. van der; Janssen, A.J.; Kuijper, J.C.; Levin, P.
1995-04-01
In this paper a short description of the ECN nuclear analysis code system is given with respect to application in HTR reactor physics calculations. First results of calculations performed on the PROTEUS benchmark are shown. Also first results of a HTGR benchmark are given. (orig.).
Reactor physics calculations on HTR type configurations
Klippel, H.T.; Hogenbirk, A.; Stad, R.C.L. van der; Janssen, A.J.; Kuijper, J.C.; Levin, P.
1995-04-01
In this paper a short description of the ECN nuclear analysis code system is given with respect to application in HTR reactor physics calculations. First results of calculations performed on the PROTEUS benchmark are shown. Also first results of a HTGR benchmark are given. (orig.)
Calculations of hyperfine parameters in antimony compounds
Svane, A.
2003-01-01
The electron contact density and electric-field gradient on the Sb nuclear position is calculated in a series of 22 Sb compounds, comprising metallic, covalent as well as ionic Sb(III) and Sb(V) systems. The full-potential linear-muffin-tin-orbitals method is used with the local-density-approximation for exchange and correlation effects. By comparison with experimental 121 Sb and 123 Sb nuclear quadrupole resonance data and 121 Sb Moessbauer data, the calibration constants relating measured quadrupole coupling constants and isomer shifts to the electric-field gradient and the electron contact density, respectively, are derived. This leads to an accurate determination of the quadrupole moment of the 121 Sb nuclear ground state as Q=-66.9 fm 2 . The difference between the mean-square radius of the 121 Sb nucleus in its excited isomeric and ground states is found to be Δ 2 >=-0.0521 fm 2
Calculation of electromagnetic parameter based on interpolation algorithm
Zhang, Wenqiang; Yuan, Liming; Zhang, Deyuan
2015-01-01
Wave-absorbing material is an important functional material of electromagnetic protection. The wave-absorbing characteristics depend on the electromagnetic parameter of mixed media. In order to accurately predict the electromagnetic parameter of mixed media and facilitate the design of wave-absorbing material, based on the electromagnetic parameters of spherical and flaky carbonyl iron mixture of paraffin base, this paper studied two different interpolation methods: Lagrange interpolation and Hermite interpolation of electromagnetic parameters. The results showed that Hermite interpolation is more accurate than the Lagrange interpolation, and the reflectance calculated with the electromagnetic parameter obtained by interpolation is consistent with that obtained through experiment on the whole. - Highlights: • We use interpolation algorithm on calculation of EM-parameter with limited samples. • Interpolation method can predict EM-parameter well with different particles added. • Hermite interpolation is more accurate than Lagrange interpolation. • Calculating RL based on interpolation is consistent with calculating RL from experiment
Reactor physics calculations in the Nordic countries
Hoeglund, R.
1995-01-01
The seventh biennial meeting on reactor physics calculations in the Nordic countries was arranged by VTT Energy on May 8-9, 1995. 26 papers on different subjects in the field of reactor physics were presented by 45 participants representing research establishments, technical universities, utilities, consultants and suppliers. Resent development and verification of the program systems of ABB Atom, Risoe, Scandpower, Studsvik and VTT Energy were the main topic of the meeting. Benchmarking of the two assembly codes CASMO-4 and HELIOS is proceeding. Cross section data calculated with CASMO-HEX have been validated for the Loviisa reactors. On core analysis ABB atom gives a description on its latest core simulator version POLCA7 with the calculation Core Master 2 and the BWR core supervision system Core Watch. Transient calculations with HEXTRAN, HEXTRAN- PLIM, TRAB, RAMONA, SIMULATE-3K and a code based on PRESTO II/POLCA7 were also presented
Calculation of driling and blasting parameters in blasting performance
Dambov, Risto; Karanakova Stefanovska, Radmila; Dambov, Ilija
2015-01-01
In all mining technology drilling and blasting parameters and works are one of the main production processes at each mine. The parameters of drilling and blasting and explosives consumption per ton of blasting mass are define economic indicators of any blasting no matter for what purpose and where mining is performed. The calculation of rock blasting should always have in mind that the methodology of calculation of all drilling and blasting parameters in blasting performance are performed for...
Some calculator programs for particle physics
Wohl, C.G.
1982-01-01
Seven calculator programs that do simple chores that arise in elementary particle physics are given. LEGENDRE evaluates the Legendre polynomial series Σa/sub n/P/sub n/(x) at a series of values of x. ASSOCIATED LEGENDRE evaluates the first-associated Legendre polynomial series Σb/sub n/P/sub n/ 1 (x) at a series of values of x. CONFIDENCE calculates confidence levels for chi 2 , Gaussian, or Poisson probability distributions. TWO BODY calculates the c.m. energy, the initial- and final-state c.m. momenta, and the extreme values of t and u for a 2-body reaction. ELLIPSE calculates coordinates of points for drawing an ellipse plot showing the kinematics of a 2-body reaction or decay. DALITZ RECTANGULAR calculates coordinates of points on the boundary of a rectangular Dalitz plot. DALITZ TRIANGULAR calculates coordinates of points on the boundary of a triangular Dalitz plot. There are short versions of CONFIDENCE (EVEN N and POISSON) that calculate confidence levels for the even-degree-of-freedom-chi 2 and the Poisson cases, and there is a short version of TWO BODY (CM) that calculates just the c.m. energy and initial-state momentum. The programs are written for the HP-97 calculator
Computing and physical methods to calculate Pu
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)
Achieving High Accuracy in Calculations of NMR Parameters
Faber, Rasmus
quantum chemical methods have been developed, the calculation of NMR parameters with quantitative accuracy is far from trivial. In this thesis I address some of the issues that makes accurate calculation of NMR parameters so challenging, with the main focus on SSCCs. High accuracy quantum chemical......, but no programs were available to perform such calculations. As part of this thesis the CFOUR program has therefore been extended to allow the calculation of SSCCs using the CC3 method. CC3 calculations of SSCCs have then been performed for several molecules, including some difficult cases. These results show...... vibrations must be included. The calculation of vibrational corrections to NMR parameters has been reviewed as part of this thesis. A study of the basis set convergence of vibrational corrections to nuclear shielding constants has also been performed. The basis set error in vibrational correction...
Injection Molding Parameters Calculations by Using Visual Basic (VB) Programming
Tony, B. Jain A. R.; Karthikeyen, S.; Alex, B. Jeslin A. R.; Hasan, Z. Jahid Ali
2018-03-01
Now a day’s manufacturing industry plays a vital role in production sectors. To fabricate a component lot of design calculation has to be done. There is a chance of human errors occurs during design calculations. The aim of this project is to create a special module using visual basic (VB) programming to calculate injection molding parameters to avoid human errors. To create an injection mold for a spur gear component the following parameters have to be calculated such as Cooling Capacity, Cooling Channel Diameter, and Cooling Channel Length, Runner Length and Runner Diameter, Gate Diameter and Gate Pressure. To calculate the above injection molding parameters a separate module has been created using Visual Basic (VB) Programming to reduce the human errors. The outcome of the module dimensions is the injection molding components such as mold cavity and core design, ejector plate design.
Dispersion parameters: impact on calculated reactor accident consequences
Aldrich, D.C.
1979-01-01
Much attention has been given in recent years to the modeling of the atmospheric dispersion of pollutants released from a point source. Numerous recommendations have been made concerning the choice of appropriate dispersion parameters. A series of calculations has been performed to determine the impact of these recommendations on the calculated consequences of large reactor accidents. Results are presented and compared in this paper.
Measuring, calculating and estimating PEP's parasitic mode loss parameters
Weaver, J.N.
1981-01-01
This note discusses various ways the parasitic mode losses from a bunched beam to a vacuum chamber can be measured, calculated or estimated. A listing of the parameter, k, for the various PEP ring components is included. A number of formulas for calculating multiple and single pass losses are discussed and evaluated for several cases. 25 refs., 1 fig., 1 tab
Calculation of coolant temperature sensitivity related to thermohydraulic parameters
Silva, F.C. da; Andrade Lima, F.R. de
1985-01-01
It is verified the viability to apply the generalized Perturbation Theory (GPT) in the calculation of sensitivity for thermal-hydraulic problems. It was developed the TEMPERA code in FORTRAN-IV to transient calculations in the axial temperature distribution in a channel of PWR reactor and the associated importance function, as well as effects of variations of thermalhydraulic parameters in the coolant temperature. The results are compared with one which were obtained by direct calculation. (M.C.K.) [pt
Sensitivity calculation of the coolant temperature regarding the thermohydraulic parameters
Andrade Lima, F.R. de; Silva, F.C. da; Thome Filho, Z.D.; Alvim, A.C.M.; Oliveira Barroso, A.C. de.
1985-01-01
It's studied the application of the Generalized Perturbation Theory (GPT) in the sensitivity calculation of thermalhydraulic problems, aiming at verifying the viability of the extension of the method. For this, the axial distribution, transient, of the coolant temperature in a PWR channel are considered. Perturbation expressions are developed using the GPT formalism, and a computer code (Tempera) is written, to calculate the channel temperature distribution and the associated importance function, as well as the effect of the thermalhydraulic parameters variations in the coolant temperature (sensitivity calculation). The results are compared with those from the direct calculation. (E.G.) [pt
Calculations in fundamental physics mechanics and heat
Heddle, T
2013-01-01
Calculations in Fundamental Physics, Volume I: Mechanics and Heat focuses on the mechanisms of heat. The manuscript first discusses motion, including parabolic, angular, and rectilinear motions, relative velocity, acceleration of gravity, and non-uniform acceleration. The book then discusses combinations of forces, such as polygons and resolution, friction, center of gravity, shearing force, and bending moment. The text looks at force and acceleration, energy and power, and machines. Considerations include momentum, horizontal or vertical motion, work and energy, pulley systems, gears and chai
Physics parameter space of tokamak ignition devices
Selcow, E.C.; Peng, Y.K.M.; Uckan, N.A.; Houlberg, W.A.
1985-01-01
This paper describes the results of a study to explore the physics parameter space of tokamak ignition experiments. A new physics systems code has been developed to perform the study. This code performs a global plasma analysis using steady-state, two-fluid, energy-transport models. In this paper, we discuss the models used in the code and their application to the analysis of compact ignition experiments. 8 refs., 8 figs., 1 tab
Microbial Communities Model Parameter Calculation for TSPA/SR
D. Jolley
2001-01-01
This calculation has several purposes. First the calculation reduces the information contained in ''Committed Materials in Repository Drifts'' (BSC 2001a) to useable parameters required as input to MING V1.O (CRWMS M and O 1998, CSCI 30018 V1.O) for calculation of the effects of potential in-drift microbial communities as part of the microbial communities model. The calculation is intended to replace the parameters found in Attachment II of the current In-Drift Microbial Communities Model revision (CRWMS M and O 2000c) with the exception of Section 11-5.3. Second, this calculation provides the information necessary to supercede the following DTN: M09909SPAMING1.003 and replace it with a new qualified dataset (see Table 6.2-1). The purpose of this calculation is to create the revised qualified parameter input for MING that will allow ΔG (Gibbs Free Energy) to be corrected for long-term changes to the temperature of the near-field environment. Calculated herein are the quadratic or second order regression relationships that are used in the energy limiting calculations to potential growth of microbial communities in the in-drift geochemical environment. Third, the calculation performs an impact review of a new DTN: M00012MAJIONIS.000 that is intended to replace the currently cited DTN: GS9809083 12322.008 for water chemistry data used in the current ''In-Drift Microbial Communities Model'' revision (CRWMS M and O 2000c). Finally, the calculation updates the material lifetimes reported on Table 32 in section 6.5.2.3 of the ''In-Drift Microbial Communities'' AMR (CRWMS M and O 2000c) based on the inputs reported in BSC (2001a). Changes include adding new specified materials and updating old materials information that has changed
Calculation system for physical analysis of boiling water reactors
Bouveret, F.
2001-01-01
Although Boiling Water Reactors generate a quarter of worldwide nuclear electricity, they have been only little studied in France. A certain interest now shows up for these reactors. So, the aim of the work presented here is to contribute to determine a core calculation methodology with CEA (Commissariat a l'Energie Atomique) codes. Vapour production in the reactor core involves great differences in technological options from pressurised water reactor. We analyse main physical phenomena for BWR and offer solutions taking them into account. BWR fuel assembly heterogeneity causes steep thermal flux gradients. The two dimensional collision probability method with exact boundary conditions makes possible to calculate accurately the flux in BWR fuel assemblies using the APOLLO-2 lattice code but induces a very long calculation time. So, we determine a new methodology based on a two-level flux calculation. Void fraction variations in assemblies involve big spectrum changes that we have to consider in core calculation. We suggest to use a void history parameter to generate cross-sections libraries for core calculation. The core calculation code has also to calculate the depletion of main isotopes concentrations. A core calculation associating neutronics and thermal-hydraulic codes lays stress on points we still have to study out. The most important of them is to take into account the control blade in the different calculation stages. (author)
Relativistic Few-Body Hadronic Physics Calculations
Polyzou, Wayne [Univ. of Iowa, Iowa City, IA (United States)
2016-06-20
The goal of this research proposal was to use ``few-body'' methods to understand the structure and reactions of systems of interacting hadrons (neutrons, protons, mesons, quarks) over a broad range of energy scales. Realistic mathematical models of few-hadron systems have the advantage that they are sufficiently simple that they can be solved with mathematically controlled errors. These systems are also simple enough that it is possible to perform complete accurate experimental measurements on these systems. Comparison between theory and experiment puts strong constraints on the structure of the models. Even though these systems are ``simple'', both the experiments and computations push the limits of technology. The important property of ``few-body'' systems is that the ``cluster property'' implies that the interactions that appear in few-body systems are identical to the interactions that appear in complicated many-body systems. Of particular interest are models that correctly describe physics at distance scales that are sensitive to the internal structure of the individual nucleons. The Heisenberg uncertainty principle implies that in order to be sensitive to physics on distance scales that are a fraction of the proton or neutron radius, a relativistic treatment of quantum mechanics is necessary. The research supported by this grant involved 30 years of effort devoted to studying all aspects of interacting two and three-body systems. Realistic interactions were used to compute bound states of two- and three-nucleon, and two- and three-quark systems. Scattering observables for these systems were computed for a broad range of energies - from zero energy scattering to few GeV scattering, where experimental evidence of sub-nucleon degrees of freedom is beginning to appear. Benchmark calculations were produced, which when compared with calculations of other groups provided an essential check on these complicated calculations. In
Calculation of the collective mass-parameter including RPA corrections
Pal, M.K.; Zawischa, D.; Speth, J.
1975-01-01
A derivation of the vibrational mass-parameter B is given which makes the consistency with RPA calculations explicit. The expected enhancement by the residual particle-hole and particle-particle interaction is demonstrated by solving the quasiparticle-RPA for deformed nuclei in the rare earth region. (orig.) [de
Microcomputer Calculation of Thermodynamic Properties from Molecular Parameters of Gases.
Venugopalan, Mundiyath
1990-01-01
Described in this article is a problem-solving activity which integrates the application of microcomputers with the learning of physical chemistry. Students use the program with spectroscopic data to calculate the thermodynamic properties and compare them with the values from the thermochemical tables. (Author/KR)
Shang Yanlong; Cai Qi; Chen Lisheng; Zhang Yangwei
2012-01-01
In this paper, the combined method of response surface and importance sampling was applied for calculation of parameter failure probability of the thermodynamic system. The mathematics model was present for the parameter failure of physics process in the thermodynamic system, by which the combination arithmetic model of response surface and importance sampling was established, then the performance degradation model of the components and the simulation process of parameter failure in the physics process of thermodynamic system were also present. The parameter failure probability of the purification water system in nuclear reactor was obtained by the combination method. The results show that the combination method is an effective method for the calculation of the parameter failure probability of the thermodynamic system with high dimensionality and non-linear characteristics, because of the satisfactory precision with less computing time than the direct sampling method and the drawbacks of response surface method. (authors)
Determination of appropriate models and parameters for premixing calculations
Park, Ik-Kyu; Kim, Jong-Hwan; Min, Beong-Tae; Hong, Seong-Wan
2008-03-15
The purpose of the present work is to use experiments that have been performed at Forschungszentrum Karlsruhe during about the last ten years for determining the most appropriate models and parameters for premixing calculations. The results of a QUEOS experiment are used to fix the parameters concerning heat transfer. The QUEOS experiments are especially suited for this purpose as they have been performed with small hot solid spheres. Therefore the area of heat exchange is known. With the heat transfer parameters fixed in this way, a PREMIX experiment is recalculated. These experiments have been performed with molten alumina (Al{sub 2}O{sub 3}) as a simulant of corium. Its initial temperature is 2600 K. With these experiments the models and parameters for jet and drop break-up are tested.
On the Relationships Between the Fundamental Parameters of Calculation Accelerograms
Savich, A. I., E-mail: office@geodyn.ru; Burdina, N. A., E-mail: nina-burdina@mail.ru [Center of the Office of Geodynamic Observations in the Power Sector, an affiliate of JSC “Institut Gidroproekt,” (Russian Federation)
2016-05-15
Analysis of published data on the fundamental parameters of actual accelerograms of strong earthquakes having peak ground acceleration A{sub max}, predominant period T{sub pr}, and duration τ{sub 0.5} at 0.5A{sub max} determined that, for earthquakes of intensity greater than 6.5 – 7.0, the relationship between these quantities is sufficiently well described by the parameters B = ATτ and C = AτT{sup −1.338}, the former of which depends little on earthquake intensity I and is almost completely determined by the earthquake magnitude, while the latter, on the contrary, weakly depends on magnitude and is determined principally by the quantity I. Methods are proposed for using the parameters B and C to improve the reliability of determining parameters of accelerograms used to calculate the seismic resistance of hydraulic engineering facilities.
Determination of appropriate models and parameters for premixing calculations
Park, Ik-Kyu; Kim, Jong-Hwan; Min, Beong-Tae; Hong, Seong-Wan
2008-03-01
The purpose of the present work is to use experiments that have been performed at Forschungszentrum Karlsruhe during about the last ten years for determining the most appropriate models and parameters for premixing calculations. The results of a QUEOS experiment are used to fix the parameters concerning heat transfer. The QUEOS experiments are especially suited for this purpose as they have been performed with small hot solid spheres. Therefore the area of heat exchange is known. With the heat transfer parameters fixed in this way, a PREMIX experiment is recalculated. These experiments have been performed with molten alumina (Al 2 O 3 ) as a simulant of corium. Its initial temperature is 2600 K. With these experiments the models and parameters for jet and drop break-up are tested
Parameter analysis calculation on characteristics of portable FAST reactor
Otsubo, Akira; Kowata, Yasuki
1998-06-01
In this report, we performed a parameter survey analysis by using the analysis program code STEDFAST (Space, TErrestrial and Deep sea FAST reactor-gas turbine system). Concerning the deep sea fast reactor-gas turbine system, calculations with many variable parameters were performed on the base case of a NaK cooled reactor of 40 kWe. We aimed at total equipment weight and surface area necessary to remove heat from the system as important values of the characteristics of the system. Electric generation power and the material of a pressure hull were specially influential for the weight. The electric generation power, reactor outlet/inlet temperatures, a natural convection heat transfer coefficient of sea water were specially influential for the area. Concerning the space reactor-gas turbine system, the calculations with the variable parameters of compressor inlet temperature, reactor outlet/inlet temperatures and turbine inlet pressure were performed on the base case of a Na cooled reactor of 40 kWe. The first and the second variable parameters were influential for the total equipment weight of the important characteristic of the system. Concerning the terrestrial fast reactor-gas turbine system, the calculations with the variable parameters of heat transferred pipe number in a heat exchanger to produce hot water of 100degC for cogeneration, compressor stage number and the kind of primary coolant material were performed on the base case of a Pb cooled reactor of 100 MWt. In the comparison of calculational results for Pb and Na of primary coolant material, the primary coolant weight flow rate was naturally large for the former case compared with for the latter case because density is very different between them. (J.P.N.)
Calculating Parameters of Chip Formation and Cutting Forces of Plastic Materials
S. V Grubyi
2017-01-01
Full Text Available In addition to the kinematics and geometric parameters of the tool, parameters of chip formation and cutting forces lay the groundwork for theoretical analysis of various types of machining.The objective of research activities is to develop a calculation technique to evaluate parameters of chip formation and cutting forces when machining such plastic materials as structural carbon and alloy steels, and aluminum alloys. The subject of research activities is directly a cutting process, algorithms and calculation methods in the field under consideration. A theoretical (calculated method to analyse parameters was used. The results of qualitative and quantitative calculations were compared with the published experimental data.As to the chip formation and cutting forces, a model with a single shear plane is analyzed, which allows a quantitative evaluation of the parameters and of the process factors. Modern domestic and foreign authors’ publications of cutting metals use this model on the reasonable grounds. The novelty of the proposed technique is that calculation of parameters and cutting forces does not require experimental research activities and is based on using the known mechanical characteristics of machined and tool materials. The calculation results are parameters, namely the shear angle, velocity factor of the chip, relative shift, friction coefficient at the front surface, cutting forces, etc. Calculation of these parameters will allow us to pass on to the thermo-physical problems, analysis of tool wear and durability, accuracy, quality and performance rate.The sequence of calculations is arranged in the developed user program in an algorithmic programming language with results in graphical or tabulated view. The calculation technique is a structural component of the cutting theory and is to be used in conducting research activities and engineering calculations in this subject area.
Hybrid Reduced Order Modeling Algorithms for Reactor Physics Calculations
Bang, Youngsuk
hybrid ROM algorithms which can be readily integrated into existing methods and offer higher computational efficiency and defendable accuracy of the reduced models. For example, the snapshots ROM algorithm is hybridized with the range finding algorithm to render reduction in the state space, e.g. the flux in reactor calculations. In another implementation, the perturbation theory used to calculate first order derivatives of responses with respect to parameters is hybridized with a forward sensitivity analysis approach to render reduction in the parameter space. Reduction at the state and parameter spaces can be combined to render further reduction at the interface between different physics codes in a multi-physics model with the accuracy quantified in a similar manner to the single physics case. Although the proposed algorithms are generic in nature, we focus here on radiation transport models used in support of the design and analysis of nuclear reactor cores. In particular, we focus on replacing the traditional assembly calculations by ROM models to facilitate the generation of homogenized cross-sections for downstream core calculations. The implication is that assembly calculations could be done instantaneously therefore precluding the need for the expensive evaluation of the few-group cross-sections for all possible core conditions. Given the generic natures of the algorithms, we make an effort to introduce the material in a general form to allow non-nuclear engineers to benefit from this work.
Calculation of dosimetry parameters for fast neutron radiotherapy
Wells, A.H.
1978-05-01
A computer simulation of the interactions of 50 MeV d/sup +/ on Be and 42 MeV p/sup +/ on Be neutron spectra with ICRU muscle tissue and Shonka A-150 tissue equivalent plastic was performed to allow computation of the charged particle spectra that result. Nuclear data were obtained from the Evaluated Nuclear Data File (ENDF) whenever possible and from the Intranuclear Cascade and Evaporation models otherwise. The dosimetry parameters calculated are: the kerma ratio, K/sub A-150//K/sub tissue/; the energy required to form an ion pair, W; and the stopping power ratio, S/sub g//sup W/.
Calculation of dosimetry parameters for fast neutron radiotherapy
Wells, A.H.
1978-05-01
A computer simulation of the interactions of 50 MeV d + on Be and 42 MeV p + on Be neutron spectra with ICRU muscle tissue and Shonka A-150 tissue equivalent plastic was performed to allow computation of the charged particle spectra that result. Nuclear data were obtained from the Evaluated Nuclear Data File (ENDF) whenever possible and from the Intranuclear Cascade and Evaporation models otherwise. The dosimetry parameters calculated are: the kerma ratio, K/sub A-150//K/sub tissue/; the energy required to form an ion pair, W; and the stopping power ratio, S/sub g//sup W/
Calculation of stationary plasma parameters in an electromagnetic trap
Karpukhin, V.I.; Lavrent'ev, O.A.; Sappa, N.N.
1978-01-01
The model of energy and particle balance is considered and the numerical calculations for stationary plasma parameters, supported by the electron injection, are obtained for a hypothetical electromagnetic trap with linear dimensions, magnetic field strength and energy contribution to plasma of the order of these parameters for the modern tokamak-type traps. The process of limitation of an effective injection current and energy contribution to plasma caused by returning of electrons to the injector due to diffusion in the velocity space is simulated. In approximation of a classical diffusion dependences are obtained of the effective energy contribution to plasma and of the parameters ntausub(E) and Tsub(i) (n is a plasma density; tausub(E)- energetic lifetime; Tsub(i) ion temperature) on electron injection current and power and on the confining magnetic field strength. It had been established that at classical character of diffusion in electromagnetic trap with above parameters one could obtain stationary plasma with ntausub(E)=10 12 cm -3 s and Tsub(i)=1keV, maintaining only by electron injection
Kim, Jung-Ha; Hill, Robin; Kuncic, Zdenka
2012-01-01
The Monte Carlo (MC) method has proven invaluable for radiation transport simulations to accurately determine radiation doses and is widely considered a reliable computational measure that can substitute a physical experiment where direct measurements are not possible or feasible. In the EGSnrc/BEAMnrc MC codes, there are several user-specified parameters and customized transport algorithms, which may affect the calculation results. In order to fully utilize the MC methods available in these codes, it is essential to understand all these options and to use them appropriately. In this study, the effects of the electron transport algorithms in EGSnrc/BEAMnrc, which are often a trade-off between calculation accuracy and efficiency, were investigated in the buildup region of a homogeneous water phantom and also in a heterogeneous phantom using the DOSRZnrc user code. The algorithms and parameters investigated include: boundary crossing algorithm (BCA), skin depth, electron step algorithm (ESA), global electron cutoff energy (ECUT) and electron production cutoff energy (AE). The variations in calculated buildup doses were found to be larger than 10% for different user-specified transport parameters. We found that using BCA = EXACT gave the best results in terms of accuracy and efficiency in calculating buildup doses using DOSRZnrc. In addition, using the ESA = PRESTA-I option was found to be the best way of reducing the total calculation time without losing accuracy in the results at high energies (few keV ∼ MeV). We also found that although choosing a higher ECUT/AE value in the beam modelling can dramatically improve computation efficiency, there is a significant trade-off in surface dose uncertainty. Our study demonstrates that a careful choice of user-specified transport parameters is required when conducting similar MC calculations. (note)
Ordinary Mathematical Models in Calculating the Aviation GTE Parameters
E. A. Khoreva
2017-01-01
Full Text Available The paper presents the analytical review results of the ordinary mathematical models of the operating process used to study aviation GTE parameters and characteristics at all stages of its creation and operation. Considers the mathematical models of the zero and the first level, which are mostly used when solving typical problems in calculating parameters and characteristics of engines.Presents a number of practical problems arising in designing aviation GTE for various applications.The application of mathematical models of the zero-level engine can be quite appropriate when the engine is considered as a component in the aircraft system to estimate its calculated individual flight performance or when modeling the flight cycle of the aircrafts of different purpose.The paper demonstrates that introduction of correction functions into the first-level mathematical models in solving typical problems (influence of the Reynolds number, characteristics deterioration of the units during the overhaul period of engine, as well as influence of the flow inhomogeneity at the inlet because of manufacturing tolerance, etc. enables providing a sufficient engineering estimate accuracy to reflect a realistic operating process in the engine and its elements.
Sensitivity calculations of integral parameters by a generalyzed perturbation theory
Santo, A.C.F. de.
1981-12-01
In this work, we first revise some concepts, concerning the neutron transport in nuclear systems. We derive the balance and importance equation. Then we discuss the neutron importance in subcritical, critical and supercritical systems. The adjoint flux is estabilished as the neutron importance for the fission process. The conventional perturbation theory is later presented. We developed a sistematic perturbative formulation in the first order variation in the distribution functions calculate the reactivity due to a system perturbation. We present in detail the flux difference and generalized functions methos. The above formulation is then extended for altered systems. We consider integral parameters of the type ratio of bilinear functionals (for which the reactivity is a particular case). We define sensitivity coeficients, for any integral parameter, corresponding to a especific system alterations. Possible aplication of the method are also discussed. In the last part of this work, we apply the perturbative formulation to the doppler reacitivity sensibility calculation, utilizing the generalized functions method. We describe in detail the compiler program written for this and some other possible aplications. (Author) [pt
WIPP shaft seal system parameters recommended to support compliance calculations
Hurtado, L.D.; Knowles, M.K. [Sandia National Labs., Albuquerque, NM (United States); Kelley, V.A.; Jones, T.L.; Ogintz, J.B. [INTERA Inc., Austin, TX (United States); Pfeifle, T.W. [RE/SPEC, Inc., Rapid City, SD (United States)
1997-12-01
The US Department of Energy plans to dispose of transuranic waste at the Waste Isolation Pilot Plant (WIPP), which is sited in southeastern New Mexico. The WIPP disposal facility is located approximately 2,150 feet (650 m) below surface in the bedded halite of the Salado Formation. Prior to initiation of disposal activities, the Department of Energy must demonstrate that the WIPP will comply with all regulatory requirements. Applicable regulations require that contaminant releases from the WIPP remain below specified levels for a period of 10,000 years. To demonstrate that the WIPP will comply with these regulations, the Department of Energy has requested that Sandia National Laboratories develop and implement a comprehensive performance assessment of the WIPP repository for the regulatory period. This document presents the conceptual model of the shaft sealing system to be implemented in performance assessment calculations conducted in support of the Compliance Certification Application for the WIPP. The model was developed for use in repository-scale calculations and includes the seal system geometry and materials to be used in grid development as well as all parameters needed to describe the seal materials. These calculations predict the hydrologic behavior of the system. Hence conceptual model development is limited to those processes that could impact the fluid flow through the seal system.
WIPP shaft seal system parameters recommended to support compliance calculations
Hurtado, L.D.; Knowles, M.K.; Kelley, V.A.; Jones, T.L.; Ogintz, J.B.; Pfeifle, T.W.
1997-12-01
The US Department of Energy plans to dispose of transuranic waste at the Waste Isolation Pilot Plant (WIPP), which is sited in southeastern New Mexico. The WIPP disposal facility is located approximately 2,150 feet (650 m) below surface in the bedded halite of the Salado Formation. Prior to initiation of disposal activities, the Department of Energy must demonstrate that the WIPP will comply with all regulatory requirements. Applicable regulations require that contaminant releases from the WIPP remain below specified levels for a period of 10,000 years. To demonstrate that the WIPP will comply with these regulations, the Department of Energy has requested that Sandia National Laboratories develop and implement a comprehensive performance assessment of the WIPP repository for the regulatory period. This document presents the conceptual model of the shaft sealing system to be implemented in performance assessment calculations conducted in support of the Compliance Certification Application for the WIPP. The model was developed for use in repository-scale calculations and includes the seal system geometry and materials to be used in grid development as well as all parameters needed to describe the seal materials. These calculations predict the hydrologic behavior of the system. Hence conceptual model development is limited to those processes that could impact the fluid flow through the seal system
Many body calculations in atomic physics
Kelly, H.P.
1985-01-01
The use of the many-body perturbation theory for atomic calculations are reviewed. The major emphasis is on the use of the linked-cluster many-body perturbation theory derived by Brueckner and Goldstone. Applications of many-body theory to calculations of hyperfine structure are examined. Auger rates and parity violation are discussed. Photoionization is reviewed, and the authors show how many-body perturbation theory can be applied to problems ranging from structural properties such as correlation energies and hyperfine structure to dynamical properties such as transitions induced by weak neutral currents and photoionization cross sections
Important parameters in ORIGEN2 calculations of spent fuel compositions
Welch, T.D.; Notz, K.J.; Andermann, R.J. Jr.
1990-01-01
The Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) is responsible for implementing federal policy for the management and permanent disposal of spent nuclear fuel from civilian nuclear power reactors and of high-level radioactive waste. The Characteristics Data Base (CDB) provides an extensive collection of data on the four waste steams that may require long-term isolation: LWR spent fuel, high-level waste, non-LWR spent fuel, and miscellaneous wastes (such as greater-than-class-C). The eight-volume report and the five supplemental menu-driven PC data bases encompass radiological characteristics, chemical compositions, physical descriptions, inventories, and projections. An overview of these data bases, which are available through the Oak Ridge National Laboratory, is provided by Notz. This paper reports that the radiological characteristics in the CDB are calculated using ORIGEN2
Brachytherapy dosimetry parameters calculated for a 131Cs source
Rivard, Mark J.
2007-01-01
A comprehensive analysis of the IsoRay Medical model CS-1 Rev2 131 Cs brachytherapy source was performed. Dose distributions were simulated using Monte Carlo methods (MCNP5) in liquid water, Solid TM , and Virtual Water TM spherical phantoms. From these results, the in-water brachytherapy dosimetry parameters have been determined, and were compared with those of Murphy et al. [Med. Phys. 31, 1529-1538 (2004)] using measurements and simulations. Our results suggest that calculations obtained using erroneous cross-section libraries should be discarded as recommended by the 2004 AAPM TG-43U1 report. Our MC Λ value of 1.046±0.019 cGy h -1 U -1 is within 1.3% of that measured by Chen et al. [Med. Phys. 32, 3279-3285 (2005)] using TLDs and the calculated results of Wittman and Fisher [Med. Phys. 34, 49-54 (2007)] using MCNP5. Using the discretized energy approach of Rivard [Appl. Radiat. Isot. 55, 775-782 (2001)] to ascertain the impact of individual 131 Cs photons on radial dose function and anisotropy functions, there was virtual equivalence of results for 29.461≤E γ ≤34.419 keV and for a mono-energetic 30.384 keV photon source. Comparisons of radial dose function and 2D anisotropy function data are also included, and an analysis of material composition and cross-section libraries was performed
Shock parameter calculations at weak interplanetary shock waves
J. M. Gloag
2005-02-01
Full Text Available A large set of interplanetary shock waves observed using the Ulysses spacecraft is analysed in order to determine their local parameters. For the first time a detailed analysis is extended to the thermodynamic properties of a large number of events. The intention is to relate the shock parameters to the requirements set by MHD shock theory. A uniform approach is adopted in the selection of up and downstream regions for this analysis and applied to all the shock waves. Initially, the general case of a 3 component adiabatic plasma is considered. However, the calculation of magnetosonic and Alfvénic Mach numbers and the ratio of downstream to upstream entropy produce some unexpected results. In some cases there is no clear increase in entropy across the shock and also the magnetosonic Mach number can be less than 1. It is found that a more discerning use of data along with an empirical value for the polytropic index can raise the distribution of downstream to upstream entropy ratios to a more acceptable level. However, it is also realised that many of these shocks are at the very weakest end of the spectrum and associated phenomena may also contribute to the explanation of these results.
Numerical precision calculations for LHC physics
Reuschle, Christian Andreas
2013-02-05
In this thesis I present aspects of QCD calculations, which are related to the fully numerical evaluation of next-to-leading order (NLO) QCD amplitudes, especially of the one-loop contributions, and the efficient computation of associated collider observables. Two interrelated topics have thereby been of concern to the thesis at hand, which give rise to two major parts. One large part is focused on the general group-theoretical behavior of one-loop QCD amplitudes, with respect to the underlying SU(N{sub c}) theory, in order to correctly and efficiently handle the color degrees of freedom in QCD one-loop amplitudes. To this end a new method is introduced that can be used in order to express color-ordered partial one-loop amplitudes with multiple quark-antiquark pairs as shuffle sums over cyclically ordered primitive one-loop amplitudes. The other large part is focused on the local subtraction of divergences off the one-loop integrands of primitive one-loop amplitudes. A method for local UV renormalization has thereby been developed, which uses local UV counterterms and efficient recursive routines. Together with suitable virtual soft and collinear subtraction terms, the subtraction method is extended to the virtual contributions in the calculations of NLO observables, which enables the fully numerical evaluation of the one-loop integrals in the virtual contributions. The method has been successfully applied to the calculation of jet rates in electron-positron annihilation to NLO accuracy in the large-N{sub c} limit.
Numerical precision calculations for LHC physics
Reuschle, Christian Andreas
2013-01-01
In this thesis I present aspects of QCD calculations, which are related to the fully numerical evaluation of next-to-leading order (NLO) QCD amplitudes, especially of the one-loop contributions, and the efficient computation of associated collider observables. Two interrelated topics have thereby been of concern to the thesis at hand, which give rise to two major parts. One large part is focused on the general group-theoretical behavior of one-loop QCD amplitudes, with respect to the underlying SU(N c ) theory, in order to correctly and efficiently handle the color degrees of freedom in QCD one-loop amplitudes. To this end a new method is introduced that can be used in order to express color-ordered partial one-loop amplitudes with multiple quark-antiquark pairs as shuffle sums over cyclically ordered primitive one-loop amplitudes. The other large part is focused on the local subtraction of divergences off the one-loop integrands of primitive one-loop amplitudes. A method for local UV renormalization has thereby been developed, which uses local UV counterterms and efficient recursive routines. Together with suitable virtual soft and collinear subtraction terms, the subtraction method is extended to the virtual contributions in the calculations of NLO observables, which enables the fully numerical evaluation of the one-loop integrals in the virtual contributions. The method has been successfully applied to the calculation of jet rates in electron-positron annihilation to NLO accuracy in the large-N c limit.
Physical and geometrical parameters of VCBS XIII: HIP 105947
Gumaan Masda, Suhail; Al-Wardat, Mashhoor Ahmed; Pathan, Jiyaulla Khan Moula Khan
2018-06-01
The best physical and geometrical parameters of the main sequence close visual binary system (CVBS), HIP 105947, are presented. These parameters have been constructed conclusively using Al-Wardat’s complex method for analyzing CVBSs, which is a method for constructing a synthetic spectral energy distribution (SED) for the entire binary system using individual SEDs for each component star. The model atmospheres are in its turn built using the Kurucz (ATLAS9) line-blanketed plane-parallel models. At the same time, the orbital parameters for the system are calculated using Tokovinin’s dynamical method for constructing the best orbits of an interferometric binary system. Moreover, the mass-sum of the components, as well as the Δθ and Δρ residuals for the system, is introduced. The combination of Al-Wardat’s and Tokovinin’s methods yields the best estimations of the physical and geometrical parameters. The positions of the components in the system on the evolutionary tracks and isochrones are plotted and the formation and evolution of the system are discussed.
On calculation of lattice parameters of refractory metal solid solutions
Barsukov, A.D.; Zhuravleva, A.D.; Pedos, A.A.
1995-01-01
Technique for calculating lattice periods of solid solutions is suggested. Experimental and calculation values of lattice periods of some solid solutions on the basis of refractory metals (V-Cr, Nb-Zr, Mo-W and other) are presented. Calculation error was correlated with experimental one. 7 refs.; 2 tabs
Parameter-free effective field theory calculation for the solar proton-fusion and hep processes
T.S. Park; L.E. Marcucci; R. Schiavilla; M. Viviani; A. Kievsky; S. Rosati; K. Kubodera; D.P. Min; M. Rho
2002-01-01
Spurred by the recent complete determination of the weak currents in two-nucleon systems up to Ο(Q 3 ) in heavy-baryon chiral perturbation theory, we carry out a parameter-free calculation of the threshold S-factors for the solar pp (proton-fusion) and hep processes in an effective field theory that combines the merits of the standard nuclear physics method and systematic chiral expansion. The power of the EFT adopted here is that one can correlate in a unified formalism the weak-current matrix elements of two-, three- and four-nucleon systems. Using the tritium β-decay rate as an input to fix the only unknown parameter in the theory, we can evaluate the threshold S factors with drastically improved precision; the results are S pp (0) = 3.94 x (1 ± 0.004) x 10 -25 MeV-b and S hep (0) = (8.6 ± 1.3) x 10 -20 keV-b. The dependence of the calculated S-factors on the momentum cutoff parameter Λ has been examined for a physically reasonable range of Λ. This dependence is found to be extremely small for the pp process, and to be within acceptable levels for the hep process, substantiating the consistency of our calculational scheme
Parameters calculation of fuel assembly with complex geometry
Wu Hongchun; Ju Haitao; Yao Dong
2006-01-01
The code DRAGON was developed for CANDU reactor by Ecole Polytechnique de Montreal of Canada. In order to validate the DRAGON code's applicability for complex geometry fuel assembly calculation, the rod shape fuel assembly of PWR benchmark problem and the plate shape fuel assembly of MTR benchmark problem were analyzed by DRAGON code. Some other shape fuel assemblies were also discussed simply. Calculation results show that the DRAGON code can be used to calculate variform fuel assembly and the precision is high. (authors)
Hardrock Elastic Physical Properties: Birch's Seismic Parameter Revisited
Wu, M.; Milkereit, B.
2014-12-01
Identifying rock composition and properties is imperative in a variety of fields including geotechnical engineering, mining, and petroleum exploration, in order to accurately make any petrophysical calculations. Density is, in particular, an important parameter that allows us to differentiate between lithologies and estimate or calculate other petrophysical properties. It is well established that compressional and shear wave velocities of common crystalline rocks increase with increasing densities (i.e. the Birch and Nafe-Drake relationships). Conventional empirical relations do not take into account S-wave velocity. Physical properties of Fe-oxides and massive sulfides, however, differ significantly from the empirical velocity-density relationships. Currently, acquiring in-situ density data is challenging and problematic, and therefore, developing an approximation for density based on seismic wave velocity and elastic moduli would be beneficial. With the goal of finding other possible or better relationships between density and the elastic moduli, a database of density, P-wave velocity, S-wave velocity, bulk modulus, shear modulus, Young's modulus, and Poisson's ratio was compiled based on a multitude of lab samples. The database is comprised of isotropic, non-porous metamorphic rock. Multi-parameter cross plots of the various elastic parameters have been analyzed in order to find a suitable parameter combination that reduces high density outliers. As expected, the P-wave velocity to S-wave velocity ratios show no correlation with density. However, Birch's seismic parameter, along with the bulk modulus, shows promise in providing a link between observed compressional and shear wave velocities and rock densities, including massive sulfides and Fe-oxides.
Development of codes for physical calculations of WWER
Novikov, A.N.
2000-01-01
A package of codes for physical calculations of WWER reactors, used at the RRC 'Kurchatov Institute' is discussed including the purpose of these codes, approximations used, degree of data verification, possibilities of automation of calculations and presentation of results, trends of further development of the codes. (Authors)
IRT-type research reactor physical calculation methodology
Carrera, W.; Castaneda, S.; Garcia, F.; Garcia, L.; Reyes, O.
1990-01-01
In the present paper an established physical calculation procedure for the research reactor of the Nuclear Research Center (CIN) is described. The results obtained by the method are compared with the ones reported during the physical start up of a reactor with similar characteristics to the CIN reactor. 11 refs
Calculation of nuclear parameters for some heavy isotopes
Corcuera, R.P.; Pinheiro, A.M.B.S.
1981-01-01
Some integrals are calculated using different weighting functions, the basic data come from two different nuclear data libraries, ENDF/B IV and ENDL/78. Significant discrepancies are found when are or the other lirary are used. (author) [pt
Calculation of integral parameters sensitivity in fast reactors
Renke, C.A.C.
1981-01-01
The variational formulation, incorporated to VARI-1D computer code is used the sensitivity calculations. At a first stage the direct method was also used with the objective of establishing a parallel between the two methods.(E.G.) [pt
Calculation of the well depth parameter to the nuclear potential
Kim, Y.U.; Kim, Y.J.
1984-01-01
Well depth parameter S or range correction factor S-1 is computed for several nuclear potentials such as square, Gaussian, exponential and Yukawa wells. A simple central force is assumed for nuclear potential between nucleons. We adopted only two parameters for potentials and attempted to clarify the fundamental nature of the nuclear forces that bind a proton and a neutron into a deuteron. Results thus obtained were used for an estimate of first order correction to simple square well model. (Author)
Calculation of parameters for an iron shield experiment
Gavazza, S.
1986-01-01
In this text is carreid out the evaluation of radiation transport methodology, comparying the calculated reactions and dose rates, for neutrons and gama-rays, with the experimental measurements obtained on iron shield, irradiated in YAYOI reactor. Were employed the ENDF/B-IV and VITAMIN-C libraries and the AMPX-II modular system for generation of cross sections, collapsed by the ANISN code. The tranpsort calculations were made by using the DOT 3.5 code, adjusting the spectrum of the iron shield boundary source to the reaction and doses rates, measured at the beginning of shield. The distributions calculated for neutrons and gamma-rays, on iron shield, presented reasonable concordance with the experimental measurements. Finally, is presented a proposal for setting up of an experimental arrangement, using the IEA-R1 reactor, with the purpose of lay down a shielding benchmark. (Author) [pt
SIMCRI: a simple computer code for calculating nuclear criticality parameters
Nakamaru, Shou-ichi; Sugawara, Nobuhiko; Naito, Yoshitaka; Katakura, Jun-ichi; Okuno, Hiroshi.
1986-03-01
This is a user's manual for a simple criticality calculation code SIMCRI. The code has been developed to facilitate criticality calculation on a single unit of nuclear fuel. SIMCRI makes an extensive survey with a little computing time. Cross section library MGCL for SIMCRI is the same one for the Monte Carlo criticality code KENOIV; it is, therefore, easy to compare the results of the two codes. SIMCRI solves eigenvalue problems and fixed source problems based on the one space point B 1 equation. The results include infinite and effective multiplication factor, critical buckling, migration area, diffusion coefficient and so on. SIMCRI is comprised in the criticality safety evaluation code system JACS. (author)
Lattice QCD Calculations in Nuclear Physics towards the Exascale
Joo, Balint
2017-01-01
The combination of algorithmic advances and new highly parallel computing architectures are enabling lattice QCD calculations to tackle ever more complex problems in nuclear physics. In this talk I will review some computational challenges that are encountered in large scale cold nuclear physics campaigns such as those in hadron spectroscopy calculations. I will discuss progress in addressing these with algorithmic improvements such as multi-grid solvers and software for recent hardware architectures such as GPUs and Intel Xeon Phi, Knights Landing. Finally, I will highlight some current topics for research and development as we head towards the Exascale era This material is funded by the U.S. Department of Energy, Office Of Science, Offices of Nuclear Physics, High Energy Physics and Advanced Scientific Computing Research, as well as the Office of Nuclear Physics under contract DE-AC05-06OR23177.
Determination of the TLD-100 physical parameters
Paucar J, J.; Picon C, C.
1998-01-01
This study was realized in the Physics service at the Radiotherapy Department of the National Institute of Neoplasic Diseases in Lima, Peru, it was determined the activation energy, the kinetic order and the frequency factor of the fifth peak of the TLD-100 thermoluminescent spectra using different algorithms. This was carried out in parallel with the implementation and design of a software and an interface associated with the Tl lecturer which allows a semiautomatic control for a thermoluminescent lecturer process. (Author)
Calculation of parameters of combined frame and roof bolting
Ivanov, S. I.; Titov, N. V.; Privalov, A. A.; Trunov, I. T.; Sarychev, V. I.
2017-10-01
The paper presents the method of calculation of the combined frame and roof bolting. Recommendations on providing joint operation of roof bolting with steel support frames are given. Graphs for determining standard rock movement, as well as for defining proof load on the yielding support, were developed.
Power extraction calculation improvement when local parameters are included
Flores-Mateos, L. M.; Hartnett, M.
2016-02-01
The improvement of the tidal resource assessment will be studied by comparing two approaches in a two-dimensional, finite difference, hydrodynamic model DIVAST-ADI; in a channel of non-varying cross-sectional area that connects two large basins. The first strategy, considers a constant trust coefficient; the second one, use the local field parameters around the turbine. These parameters are obtained after applying the open channel theory in the tidal stream and after considering the turbine as a linear momentum actuator disk. The parameters correspond to the upstream and downstream, with respect to the turbine, speeds and depths; also the blockage ratio, the wake velocity and the bypass coefficients and they have already been incorporated in the model. The figure (a) shows the numerical configuration at high tide developed with DIVAST-ADI. The experiment undertakes two open boundary conditions. The first one is a sinusoidal forcing introduced as a water level located at (I, J=1) and the second one, indicate that a zero velocity and a constant water depth were kept (I, J=362); when the turbine is introduced it is placed in the middle of the channel (I=161, J=181). The influence of the turbine in the velocity and elevation around the turbine region is evident; figure (b) and (c) shows that the turbine produces a discontinuity in the depth and velocity profile, when we plot a transect along the channel. Finally, the configuration implemented reproduced with satisfactory accuracy the quasi-steady flow condition, even without presenting shock-capturing capability. Also, the range of the parameters 0.01<α 4<0.55, $0
Calculation of trajectory parameters of long pass in basketball.
Charikova K.M.
2011-08-01
Full Text Available Values of a ball's flight trajectory parameters depending on a distance of long pass, a corner of a ball's start and height of a throwing point are submitted in article. Coordinates of reference points installation for training to long pass with an optimum trajectory of a ball's flight are designed. Requirements to simulators design are determined. Corners of ball's long pass performance in various game situations are recommended.
Machine learning of parameters for accurate semiempirical quantum chemical calculations
Dral, Pavlo O.; Lilienfeld, O. Anatole von; Thiel, Walter
2015-01-01
We investigate possible improvements in the accuracy of semiempirical quantum chemistry (SQC) methods through the use of machine learning (ML) models for the parameters. For a given class of compounds, ML techniques require sufficiently large training sets to develop ML models that can be used for adapting SQC parameters to reflect changes in molecular composition and geometry. The ML-SQC approach allows the automatic tuning of SQC parameters for individual molecules, thereby improving the accuracy without deteriorating transferability to molecules with molecular descriptors very different from those in the training set. The performance of this approach is demonstrated for the semiempirical OM2 method using a set of 6095 constitutional isomers C 7 H 10 O 2 , for which accurate ab initio atomization enthalpies are available. The ML-OM2 results show improved average accuracy and a much reduced error range compared with those of standard OM2 results, with mean absolute errors in atomization enthalpies dropping from 6.3 to 1.7 kcal/mol. They are also found to be superior to the results from specific OM2 reparameterizations (rOM2) for the same set of isomers. The ML-SQC approach thus holds promise for fast and reasonably accurate high-throughput screening of materials and molecules
Ainsworth, T.L.
1983-01-01
The Δ(1232) plays an important role in determining the properties of nuclear and neutron matter. The effects of the Δ resonance are incorporated explicitly by using a coupled channel formalism. A method for constraining a lowest order variational calculation, appropriate when nucleon internal degrees of freedom are made explicity, is presented. Different N-N potentials were calculated and fit to phase shift data and deuteron properties. The potentials were constructed to test the relative importance of the Δ resonance on nuclear properties. The symmetry energy and incompressibility of nuclear matter are generally reproduced by this calculation. Neutron matter results lead to appealing neutron star models. Fermi liquid parameters for 3 He are calculated with a model that includes both direct and induced terms. A convenient form of the direct interaction is obtained in terms of the parameters. The form of the direct interaction ensures that the forward scattering sum rule (Pauli principle) is obeyed. The parameters are adjusted to fit the experimentally determined F 0 /sup s/, F 0 /sup a/, and F 1 /sup s/ Landau parameters. Higher order Landau parameters are calculated by the self-consistent solution of the equations; comparison to experiment is good. The model also leads to a preferred value for the effective mass of 3 He. Of the three parameters only one shows any dependence on pressure. An exact sum rule is derived relating this parameter to a specific summation of Landau parameters
Calculation of Grounding Grids Parameter at Arbitrary Geometry
Carlos L. B. Silva
2017-06-01
Full Text Available This paper deals with the computation of ground resistance, surface voltage, touch voltage and step voltage, to mesh with horizontal wires arranged in different angles. The computer program implemented used in the mathematical modeling is based on the method proposed by Heppe, which allows obtaining the grounding parameters for homogeneous soil and soil stratified in two layers. The results obtained with the proposed method will be compared with other methods in literature. Also will be presented the results of a grounding grid using wires at various angles.
Methods of calculating engineering parameters for gas separations
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.
Kuster, E.; Moore, R.; Lust, L.; Kemper, P. [Georgia Inst. of Tech., Atlanta, GA (United States)
1996-12-31
A Method of Moments (MoM) electromagnetic model of percolating conducting films was applied to calculate the effective parameters of the composite formed by conducting inclusions placed within a dispersive magnetic but nondispersive dielectric matrix. The MoM calculations demonstrate a coupling between the magnetic properties of the matrix and the effective composite permittivity and frequency dispersion of the composite. The coupling of permittivity and permeability is observed near the percolation threshold of the composite and for high conductivity inclusions. The prediction agrees with physical expectations since near percolation the conduction correlation length dominates the effective permittivity of the composite and this correlation length is determined by both the permittivity and permeability of the composite.
Opacity calculations for extreme physical systems: code RACHEL
Drska, Ladislav; Sinor, Milan
1996-08-01
Computer simulations of physical systems under extreme conditions (high density, temperature, etc.) require the availability of extensive sets of atomic data. This paper presents basic information on a self-consistent approach to calculations of radiative opacity, one of the key characteristics of such systems. After a short explanation of general concepts of the atomic physics of extreme systems, the structure of the opacity code RACHEL is discussed and some of its applications are presented.
Three-dimensional Monte Carlo calculation of some nuclear parameters
Günay, Mehtap; Şeker, Gökmen
2017-09-01
In this study, a fusion-fission hybrid reactor system was designed by using 9Cr2WVTa Ferritic steel structural material and the molten salt-heavy metal mixtures 99-95% Li20Sn80 + 1-5% RG-Pu, 99-95% Li20Sn80 + 1-5% RG-PuF4, and 99-95% Li20Sn80 + 1-5% RG-PuO2, as fluids. The fluids were used in the liquid first wall, blanket and shield zones of a fusion-fission hybrid reactor system. Beryllium (Be) zone with the width of 3 cm was used for the neutron multiplication between the liquid first wall and blanket. This study analyzes the nuclear parameters such as tritium breeding ratio (TBR), energy multiplication factor (M), heat deposition rate, fission reaction rate in liquid first wall, blanket and shield zones and investigates effects of reactor grade Pu content in the designed system on these nuclear parameters. Three-dimensional analyses were performed by using the Monte Carlo code MCNPX-2.7.0 and nuclear data library ENDF/B-VII.0.
Three-dimensional Monte Carlo calculation of some nuclear parameters
Günay Mehtap
2017-01-01
Full Text Available In this study, a fusion-fission hybrid reactor system was designed by using 9Cr2WVTa Ferritic steel structural material and the molten salt-heavy metal mixtures 99–95% Li20Sn80 + 1-5% RG-Pu, 99–95% Li20Sn80 + 1-5% RG-PuF4, and 99–95% Li20Sn80 + 1-5% RG-PuO2, as fluids. The fluids were used in the liquid first wall, blanket and shield zones of a fusion–fission hybrid reactor system. Beryllium (Be zone with the width of 3 cm was used for the neutron multiplication between the liquid first wall and blanket. This study analyzes the nuclear parameters such as tritium breeding ratio (TBR, energy multiplication factor (M, heat deposition rate, fission reaction rate in liquid first wall, blanket and shield zones and investigates effects of reactor grade Pu content in the designed system on these nuclear parameters. Three-dimensional analyses were performed by using the Monte Carlo code MCNPX-2.7.0 and nuclear data library ENDF/B-VII.0.
Microscopic calculation of parameters of the sdg interacting boson model for 104-110Pd isotopes
Liu Yong
1995-01-01
The parameters of the sdg interacting boson model Hamiltonian are calculated for the 104-110 Pd isotopes. The calculations utilize the microscopic procedure based on the Dyson boson mapping proposed by Yang-Liu-Qi and extended to include the g boson effects. The calculated parameters reproduce those values from the phenomenological fits. The resulting spectra are compared with the experimental spectra
Status and prospects for lattice calculations in heavy quark physics
Wittig, H.; Forschungszentrum Juelich GmbH
1996-06-01
The current status of lattice calculation of weak matrix elements for heavy quark systems is reviewed. After an assessment of systematic errors in present simulations, results for the B meson decay constant, the B parameter B B and semi-leptonic heavy-to-light and heavy-to-heavy transitions are discussed. The final topic are lattice results for heavy baryon spectroscopy. (orig.)
Perturbative calculations and their application to Higgs physics
Zirke, Tom J.E.
2014-09-01
In this thesis the numerical calculation of IR-finite two-loop integrals for processes related to Higgs physics in four-dimensional regularization regarding especilla the process gg→HZ is described. An application to two-loop vacuum integrals with φ→γγ at NLO QCD is presented. (HSI)
Quantum Monte Carlo calculation of the Fermi-liquid parameters in the two-dimensional electron gas
Kwon, Y.; Ceperley, D.M.; Martin, R.M.
1994-01-01
Excitations of the two-dimensional electron gas, including many-body effects, are calculated with a variational Monte Carlo method. Correlated sampling is introduced to calculate small energy differences between different excitations. The usual pair-product (Slater-Jastrow) trial wave function is found to lack certain correlations entirely so that backflow correlation is crucial. From the excitation energies calculated here, we determine Fermi-liquid parameters and related physical quantities such as the effective mass and the Lande g factor of the system. Our results for the effective mass are compared with previous analytic calculations
Recommended environmental dose calculation methods and Hanford-specific parameters
Schreckhise, R.G.; Rhoads, K.; Napier, B.A.; Ramsdell, J.V.; Davis, J.S.
1993-03-01
This document was developed to support the Hanford Environmental Dose overview Panel (HEDOP). The Panel is responsible for reviewing all assessments of potential doses received by humans and other biota resulting from the actual or possible environmental releases of radioactive and other hazardous materials from facilities and/or operations belonging to the US Department of Energy on the Hanford Site in south-central Washington. This document serves as a guide to be used for developing estimates of potential radiation doses, or other measures of risk or health impacts, to people and other biota in the environs on and around the Hanford Site. It provides information to develop technically sound estimates of exposure (i.e., potential or actual) to humans or other biotic receptors that could result from the environmental transport of potentially harmful materials that have been, or could be, released from Hanford operations or facilities. Parameter values and information that are specific to the Hanford environs as well as other supporting material are included in this document
Recommended environmental dose calculation methods and Hanford-specific parameters
Schreckhise, R.G.; Rhoads, K.; Napier, B.A.; Ramsdell, J.V. (Pacific Northwest Lab., Richland, WA (United States)); Davis, J.S. (Westinghouse Hanford Co., Richland, WA (United States))
1993-03-01
This document was developed to support the Hanford Environmental Dose overview Panel (HEDOP). The Panel is responsible for reviewing all assessments of potential doses received by humans and other biota resulting from the actual or possible environmental releases of radioactive and other hazardous materials from facilities and/or operations belonging to the US Department of Energy on the Hanford Site in south-central Washington. This document serves as a guide to be used for developing estimates of potential radiation doses, or other measures of risk or health impacts, to people and other biota in the environs on and around the Hanford Site. It provides information to develop technically sound estimates of exposure (i.e., potential or actual) to humans or other biotic receptors that could result from the environmental transport of potentially harmful materials that have been, or could be, released from Hanford operations or facilities. Parameter values and information that are specific to the Hanford environs as well as other supporting material are included in this document.
Pereira, A.; Broed, R.
2002-03-01
In this report, several issues related to the probabilistic methodology for performance assessments of repositories for high-level nuclear waste and spent fuel are addressed. Random Monte Carlo sampling is used to make uncertainty analyses for the migration of four nuclides and a decay chain in the geosphere. The nuclides studied are cesium, chlorine, iodine and carbon, and radium from a decay chain. A procedure is developed to take advantage of the information contained in the hydrogeological data obtained from a three-dimensional discrete fracture model as the input data for one-dimensional transport models for use in Monte Carlo calculations. This procedure retains the original correlations between parameters representing different physical entities, namely, between the groundwater flow rate and the hydrodynamic dispersion in fractured rock, in contrast with the approach commonly used that assumes that all parameters supplied for the Monte Carlo calculations are independent of each other. A small program is developed to allow the above-mentioned procedure to be used if the available three-dimensional data are scarce for Monte Carlo calculations. The program allows random sampling of data from the 3-D data distribution in the hydrogeological calculations. The impact of correlations between the groundwater flow and the hydrodynamic dispersion on the uncertainty associated with the output distribution of the radionuclides' peak releases is studied. It is shown that for the SITE-94 data, this impact can be disregarded. A global sensitivity analysis is also performed on the peak releases of the radionuclides studied. The results of these sensitivity analyses, using several known statistical methods, show discrepancies that are attributed to the limitations of these methods. The reason for the difficulties is to be found in the complexity of the models needed for the predictions of radionuclide migration, models that deliver results covering variation of several
The effects of some parameters on the calculated 1H NMR relaxation times of cell water
Koivula, A.; Suominen, K.; Kiviniitty, K.
1976-01-01
The effect of some parameters on the longitudinal and transverse relaxation times is calculated and a comparison between the calculated relaxation times with the results of different measurements is made. (M.S.)
Calculating background levels for ecological risk parameters in toxic harbor sediment
Leadon, C.J.; McDonnell, T.R.; Lear, J.; Barclift, D.
2007-01-01
Establishing background levels for biological parameters is necessary in assessing the ecological risks from harbor sediment contaminated with toxic chemicals. For chemicals in sediment, the term contaminated is defined as having concentrations above background and significant human health or ecological risk levels. For biological parameters, a site could be considered contaminated if levels of the parameter are either more or less than the background level, depending on the specific parameter. Biological parameters can include tissue chemical concentrations in ecological receptors, bioassay responses, bioaccumulation levels, and benthic community metrics. Chemical parameters can include sediment concentrations of a variety of potentially toxic chemicals. Indirectly, contaminated harbor sediment can impact shellfish, fish, birds, and marine mammals, and human populations. This paper summarizes the methods used to define background levels for chemical and biological parameters from a survey of ecological risk investigations of marine harbor sediment at California Navy bases. Background levels for regional biological indices used to quantify ecological risks for benthic communities are also described. Generally, background stations are positioned in relatively clean areas exhibiting the same physical and general chemical characteristics as nearby areas with contaminated harbor sediment. The number of background stations and the number of sample replicates per background station depend on the statistical design of the sediment ecological risk investigation, developed through the data quality objective (DQO) process. Biological data from the background stations can be compared to data from a contaminated site by using minimum or maximum background levels or comparative statistics. In Navy ecological risk assessments (ERA's), calculated background levels and appropriate ecological risk screening criteria are used to identify sampling stations and sites with contaminated
Physical and geometrical parameters of ANNA critical assemblies. Pt. 2
Malewski, S.; Dabrowski, C.
1973-01-01
An extended analysis of four critical configurations of ANNA Assembly has been performed. Diffusion parameters of the thermal group and of one or three epithermal groups have been determined. Using these data the critical calculations have been carried out and the main neutron density distributions presented. The role of some neutron processes in these systems and their influence on integral parameters has been considered. The calculated quantities have been compared with the available experimental data. (author)
Chemical abundances and physical parameters of RR Lyrae stars
Manduca, A.
1980-01-01
A grid of model stellar atmospheres has been calculated with a range of physical parameters which effectively cover RR Lyrae stars over all phases of their pulsation cycle. The models, calculated with the computer program MARCS, are flux-constant and include the effects of convection and line blanketing. Synthetic spectra were calculated for these models from 3000 A to 9600 A at 0.1 A resolution using the computer program SSG. These spectra were used directly in the applications below and were also used to computer theoretical colors on the UBVR, Stromgren uvby, and Walraven systems for the models. The uvby colors were used in determinations of effective temperature and surface gravity from photometry by various observers. The models, synthetic spectra, and colors were then applied to the problems detailed below. The data collected by Freeman and Rodgers (1975) for 25 RR Lyrae stars in ω Cen was reanalyzed with an alternative, synthetic spectrum approach to the calibration of their theoretical relations. The results confirm a wide range in calcium abundance for the stars in the cluster but at much lower values than reported by Freeman and Rodgers: a range of [Ca/H] = -1.0 to -1.9 was found. A theoretical calibration was performed for the ΔS system of determining metal abundances for RR Lyrae stars. The results support the existing empirical calibration of Butler in the range [Fe/H] = -0.6 to -2.2 and indicate how the calibration should be extrapolated to even lower metal abundances. For higher metal abundances, however, our calibration yields [Fe/H] values lower than Butler by as much as 0.4. Possible explanations of this discrepancy are investigated and the implications are discussed
Parameters calculation of a shielding experiment and evaluation of calculation methodology
Gavazza, S.; Otto, A.C.; Gomes, I.C.; Maiorino, J.R.
1986-01-01
In this text is carried out the evaluation of radiation transport methodology, comparying the calculated reactions and dose rates, for neutrons and gamma-rays, with the experimental measurements obtained on iron shield, irradiated in YAYOI reactor. Were employed the ENDF/B-IV and VITAMIN-C libraries and the AMPX-II modular system for generation of cross sections, collapsed by the ANISN code. The transport calculation were made by using the DOT 3.5 code, adjusting the spectrum of the iron shield boundary source to the reactions and dose rates, measured at the beginning of shield. The distributions calculated for neutrons and gamma-rays, on iron shield, presented coherence with the experimental measurements. (Author) [pt
RP-10: commissioning. Reproduction by physical experiences calculation
Higa, Manabu; Madariaga, M.R.
1990-01-01
This work presents the neutronic calculation results, most of which were carried out after such experiences, to verify the calculation methodology developed at the Analysis and Calculation Department of the National Atomic Energy Commission (CNEA). The results obtained were satisfactory, proving that the calculation methodology used is adequate for the design of this type of reactors. The only important disagreement is to evaluate the reactivity excess and cut reactivity, but this responds to a criterion difference and/or that of definition for these parameters. The positions of criticality with errors lower than 100 pcm were predicted. The differential and integral reactivities for the calibration of bars, as well as the flux distribution, are reproduced in a reasonable degree in relation to differences inferior to 10%. (Author) [es
Acceleration parameters for fluid physics with accelerating bodies
Gledhill, Irvy MA
2016-06-01
Full Text Available to an acceleration parameter that appears to be new in fluid physics, but is known in cosmology. A selection of cases for rectilinear acceleration has been chosen to illustrate the point that this parameter alone does not govern regimes of flow about significantly...
The effect of rock electrical parameters on the calculation of reservoir saturation
Li, Xiongyan; Qin, Ruibao; Liu, Chuncheng; Mao, Zhiqiang
2013-01-01
The error in calculating a reservoir saturation caused by the error in the cementation exponent, m, and the saturation exponent, n, should be analysed. In addition, the influence of m and n on the reservoir saturation should be discussed. Based on the Archie formula, the effect of variables m and n on the reservoir saturation is analysed, while the formula for the error in calculating the reservoir saturation, caused by the error in m and n, is deduced, and the main factors affecting the error in reservoir saturation are illustrated. According to the physical meaning of m and n, it can be interpreted that they are two independent parameters, i.e., there is no connection between m and n. When m and n have the same error, the impact of the variables on the calculation of the reservoir saturation should be compared. Therefore, when the errors of m and n are respectively equal to 0.2, 0.4 and 0.6, the distribution range of the errors in calculating the reservoir saturation is analysed. However, in most cases, the error of m and n is about 0.2. When the error of m is 0.2, the error in calculating the reservoir saturation ranges from 0% to 35%. Meanwhile, when the error in n is 0.2, the error in calculating the reservoir saturation is almost always below 5%. On the basis of loose sandstone, medium sandstone, tight sandstone, conglomerate, tuff, breccia, basalt, andesite, dacite and rhyolite, this paper first analyses the distribution range and change amplitude of m and n. Second, the impact of m and n on the calculation of reservoir saturation is elaborated upon. With regard to each lithology, the distribution range and change amplitude of m are greater than those of n. Therefore, compared with n, the effect of m on the reservoir saturation is stronger. The influence of m and n on the reservoir saturation is determined, and the error in calculating the reservoir saturation caused by the error of m and n is calculated. This is theoretically and practically significant for
A calculation of the physical mass of sigma meson
Morones-Ibarra, J.R.; Santos-Guevara, Ayax
2007-01-01
We calculate the physical mass and the width of the sigma meson by considering that it couples in vacuum to two virtual pions. The mass is calculated by using the spectral function, and we find that it is about 600 MeV. In addition, we obtained 220 MeV as the value for the width of its spectral function. The value obtained for the mass is in good agreement with that reported in the Particle Data Book for the σ meson, which is also named f 0 (600). This result also shows that σ-meson can be considered as a two-pion resonance. (author)
Learning about physical parameters: the importance of model discrepancy
Brynjarsdóttir, Jenný; O'Hagan, Anthony
2014-01-01
Science-based simulation models are widely used to predict the behavior of complex physical systems. It is also common to use observations of the physical system to solve the inverse problem, that is, to learn about the values of parameters within the model, a process which is often called calibration. The main goal of calibration is usually to improve the predictive performance of the simulator but the values of the parameters in the model may also be of intrinsic scientific interest in their own right. In order to make appropriate use of observations of the physical system it is important to recognize model discrepancy, the difference between reality and the simulator output. We illustrate through a simple example that an analysis that does not account for model discrepancy may lead to biased and over-confident parameter estimates and predictions. The challenge with incorporating model discrepancy in statistical inverse problems is being confounded with calibration parameters, which will only be resolved with meaningful priors. For our simple example, we model the model-discrepancy via a Gaussian process and demonstrate that through accounting for model discrepancy our prediction within the range of data is correct. However, only with realistic priors on the model discrepancy do we uncover the true parameter values. Through theoretical arguments we show that these findings are typical of the general problem of learning about physical parameters and the underlying physical system using science-based mechanistic models. (paper)
Druce, C.H.; Barrett, B.R. (Arizona Univ., Tucson (USA). Dept. of Physics); Pittel, S. (Delaware Univ., Newark (USA). Bartol Research Foundation); Duval, P.D. (BEERS Associates, Reston, VA (USA))
1985-07-11
The parameters of the Majorana interaction of the neutron-proton interacting boson model are calculated for the Hg isotopes. The calculations utilize the Otsuka-Arima-Iachello mapping procedure and also lead to predictions for the other boson parameters. The resulting spectra are compared with experimental spectra and those obtained from phenomenological fits.
Druce, C. H.; Pittel, S.; Barrett, B. R.; Duval, P. D.
1985-07-01
The parameters of the Majorana interaction of the neutron-proton interacting boson model are calculated for the Hg isotopes. The calculations utilize the Otsuka-Arima-Iachello mapping procedure and also lead to predictions for the other boson parameters. The resulting spectra are compared with experimental spectra and those obtained from phenomenological fits.
The spectroscopic orbits and physical parameters of GG Carinae
Marchiano, P.; Brandi, E.; Muratore, M. F.; Quiroga, C.; Ferrer, O. E.; García, L. G.
2012-04-01
Aims: GG Car is an eclipsing binary classified as a B[e] supergiant star. The aims of our study are to improve the orbital elements of the binary system in order to obtain the actual orbital period of this system. We also compare the spectral energy distribution of the observed fluxes over a wide wavelength range with a model of a circumstellar envelope composed of gas and dust. This fitting allows us to derive the physical parameters of the system and its environment, as well as to obtain an estimation of the distance to GG Car. Methods: We analyzed about 55 optical and near infrared spectrograms taken during 1996-2010. The spectroscopic orbits were obtained by measuring the radial velocities of the blueshifted absorptions of the He I P-Cygni profiles, which are very representative of the orbital motion of both stars. On the other hand, we modeled the spectral energy distribution of GG Car, proposing a simple model of a spherical envelope consisting of a layer close to the central star composed of ionized gas and other outermost layers composed of dust. Its effect on the spectral energy distribution considering a central B-type star is presented. Comparing the model with the observed continuum energy distribution of GG Car, we can derive fundamental parameters of the system, as well as global physical properties of the gas and dust envelope. It is also possible to estimate the distance taking the spectral regions into account where the theoretical data fit the observational data very well and using the set of parameters obtained and the value of the observed flux for different wavelengths. Results: For the first time, we have determined the orbits for both components of the binary through a detailed study of the He I lines, at λλ4471, 5875, 6678, and 7065 Å, thereby obtaining an orbital period of 31.033 days. An eccentric orbit with e = 0.28 and a mass ratio q = 2.2 ± 0.9 were calculated. Comparing the model with the observed continuum energy distribution of
Reactor physics calculations on the Dutch small HTR concept
Kuijper, J.C.; Haas, J.B.M. de; Klippel, H.T.; Hogenbirk, A.; Oppe, J.; Sciolla, C.M.; Stad, R.C.L. van der; Zhang, B.C.
1997-06-01
As part of the activities within the framework of the development of INCOGEN, a 'Dutch' conceptual design of a smaller HTR, the ECN reactor physics code system has been extended with the capability to perform combined neutronics and thermal hydraulics steady-state, burnup and transient core calculations on pebble-bed type HTRs, by joining the general purpose reactor code PANTHER and the HTR thermal hydraulics code THERMIX/DIREKT in the PANTHERMIX code combination. The validation of the ECN code system for HTR applications is still in progress, but some promising first calculation results on unit cell and whole core geometries are presented, which indicate that the extended ECN code system is quite suitable for performing the pebble-bed HTR core calculations, required in the INCOGEN core design and optimization process. (orig.)
Reactor physics calculations on the Dutch small HTR concept
Kuijper, J.C.; Hass, J.B.M. De; Klippel, H.Th.; Hogenbirk, A.; Oppe, J.; Sciolla, C.; Stad, R.C.L. Van Der; Zhang, B.C.
1997-01-01
As part of the activities within the framework of the development of INCOGEN, a ''Dutch'' conceptual design of a small HTR, the ECN reactor physics code system has been extended with the capability to perform combined neutronics and thermal hydraulics steady-state, burnup and transient core calculations on pebble-bed type HTRS, by joining the general purpose reactor code PANTHER and the HTR thermal hydraulics code THERMIX/DIREKT in the PANTHERMIX code combination. The validation of the ECN code system for HTR applications is still in progress, but some promising first calculation results on unit cell and whole core geometries are presented, which indicate that the extended ECN code system is quite suitable for performing the pebble-bed HTR core calculations, required in the INCOGEN core design and optimization process. (author)
M. Gross
2004-01-01
The purpose of this scientific analysis is to define the sampled values of stochastic (random) input parameters for (1) rockfall calculations in the lithophysal and nonlithophysal zones under vibratory ground motions, and (2) structural response calculations for the drip shield and waste package under vibratory ground motions. This analysis supplies: (1) Sampled values of ground motion time history and synthetic fracture pattern for analysis of rockfall in emplacement drifts in nonlithophysal rock (Section 6.3 of ''Drift Degradation Analysis'', BSC 2004 [DIRS 166107]); (2) Sampled values of ground motion time history and rock mechanical properties category for analysis of rockfall in emplacement drifts in lithophysal rock (Section 6.4 of ''Drift Degradation Analysis'', BSC 2004 [DIRS 166107]); (3) Sampled values of ground motion time history and metal to metal and metal to rock friction coefficient for analysis of waste package and drip shield damage to vibratory motion in ''Structural Calculations of Waste Package Exposed to Vibratory Ground Motion'' (BSC 2004 [DIRS 167083]) and in ''Structural Calculations of Drip Shield Exposed to Vibratory Ground Motion'' (BSC 2003 [DIRS 163425]). The sampled values are indices representing the number of ground motion time histories, number of fracture patterns and rock mass properties categories. These indices are translated into actual values within the respective analysis and model reports or calculations. This report identifies the uncertain parameters and documents the sampled values for these parameters. The sampled values are determined by GoldSim V6.04.007 [DIRS 151202] calculations using appropriate distribution types and parameter ranges. No software development or model development was required for these calculations. The calculation of the sampled values allows parameter uncertainty to be incorporated into the rockfall and structural response calculations that support development of the seismic scenario for the
В.Т. Чемерис
2006-04-01
Full Text Available There is a method of simplified calculation and design parameters choice elaborated in this article with corresponding basing for the induction system of electron-beam sterilizer on the base of linear induction accelerator taking into account the parameters of magnetic material for production of cores and parameters of pulsed voltage.
Algorithms and parameters for improved accuracy in physics data libraries
Batič, M; Hoff, G; Pia, M G; Saracco, P; Han, M; Kim, C H; Hauf, S; Kuster, M; Seo, H
2012-01-01
Recent efforts for the improvement of the accuracy of physics data libraries used in particle transport are summarized. Results are reported about a large scale validation analysis of atomic parameters used by major Monte Carlo systems (Geant4, EGS, MCNP, Penelope etc.); their contribution to the accuracy of simulation observables is documented. The results of this study motivated the development of a new atomic data management software package, which optimizes the provision of state-of-the-art atomic parameters to physics models. The effect of atomic parameters on the simulation of radioactive decay is illustrated. Ideas and methods to deal with physics models applicable to different energy ranges in the production of data libraries, rather than at runtime, are discussed.
Influence of buildings geometrical and physical parameters on thermal cooling load
Melo, C.
1980-09-01
A more accurate method to evaluate the thermal cooling load in buildings and to analyze the influence of geometrical and physical parameters on air conditioning calculations is presented. The sensitivity of the cooling load, considering the thermal capacity of the materials, was simulated in a computer for several different situations. (Author) [pt
Indexes and parameters of activity in solar-terrestrial physics
Minasyants, G.S.; Minasyants, T.M.
2005-01-01
The daily variation of different indexes and parameters of the solar-terrestrial physics at the 23 cycle were considered to find the most important from them for the forecast of geomagnetic activity. The validity of application of the Wolf numbers in quality of the characteristic of solar activity at sunspots is confirmed. The best geo-effective parameter in the arrival of the interplanetary shock from coronal mass ejection to an orbit of the Earth. (author)
Calculating the mounting parameters for Taylor Spatial Frame correction using computed tomography.
Kucukkaya, Metin; Karakoyun, Ozgur; Armagan, Raffi; Kuzgun, Unal
2011-07-01
The Taylor Spatial Frame uses a computer program-based six-axis deformity analysis. However, there is often a residual deformity after the initial correction, especially in deformities with a rotational component. This problem can be resolved by recalculating the parameters and inputting all new deformity and mounting parameters. However, this may necessitate repeated x-rays and delay treatment. We believe that error in the mounting parameters is the main reason for most residual deformities. To prevent these problems, we describe a new calculation technique for determining the mounting parameters that uses computed tomography. This technique is especially advantageous for deformities with a rotational component. Using this technique, exact calculation of the mounting parameters is possible and the residual deformity and number of repeated x-rays can be minimized. This new technique is an alternative method to accurately calculating the mounting parameters.
Hsu, Wei-Ting; Loh, Chin-Hsiung; Chao, Shu-Hsien
2015-03-01
Stochastic subspace identification method (SSI) has been proven to be an efficient algorithm for the identification of liner-time-invariant system using multivariate measurements. Generally, the estimated modal parameters through SSI may be afflicted with statistical uncertainty, e.g. undefined measurement noises, non-stationary excitation, finite number of data samples etc. Therefore, the identified results are subjected to variance errors. Accordingly, the concept of the stabilization diagram can help users to identify the correct model, i.e. through removing the spurious modes. Modal parameters are estimated at successive model orders where the physical modes of the system are extracted and separated from the spurious modes. Besides, an uncertainty computation scheme was derived for the calculation of uncertainty bounds for modal parameters at some given model order. The uncertainty bounds of damping ratios are particularly interesting, as the estimation of damping ratios are difficult to obtain. In this paper, an automated stochastic subspace identification algorithm is addressed. First, the identification of modal parameters through covariance-driven stochastic subspace identification from the output-only measurements is used for discussion. A systematic way of investigation on the criteria for the stabilization diagram is presented. Secondly, an automated algorithm of post-processing on stabilization diagram is demonstrated. Finally, the computation of uncertainty bounds for each mode with all model order in the stabilization diagram is utilized to determine system natural frequencies and damping ratios. Demonstration of this study on the system identification of a three-span steel bridge under operation condition is presented. It is shown that the proposed new operation procedure for the automated covariance-driven stochastic subspace identification can enhance the robustness and reliability in structural health monitoring.
Automated calculation of matrix elements and physics motivated observables
Was, Z.
2017-11-01
The central aspect of my personal scientific activity, has focused on calculations useful for interpretation of High Energy accelerator experimental results, especially in a domain of precision tests of the Standard Model. My activities started in early 80’s, when computer support for algebraic manipulations was in its infancy. But already then it was important for my work. It brought a multitude of benefits, but at the price of some inconvenience for physics intuition. Calculations became more complex, work had to be distributed over teams of researchers and due to automatization, some aspects of the intermediate results became more difficult to identify. In my talk I will not be very exhaustive, I will present examples from my personal research only: (i) calculations of spin effects for the process e + e - → τ + τ - γ at Petra/PEP energies, calculations (with the help of the Grace system of Minami-tateya group) and phenomenology of spin amplitudes for (ii) e + e - → 4f and for (iii) e + e - → νeν¯eγγ processes, (iv) phenomenology of CP-sensitive observables for Higgs boson parity in H → τ + τ -, τ ± → ν2(3)π cascade decays.
Analytical calculations by computer in physics and mathematics
Gerdt, V.P.; Tarasov, O.V.; Shirokov, D.V.
1978-01-01
The review of present status of analytical calculations by computer is given. Some programming systems for analytical computations are considered. Such systems as SCHOONSCHIP, CLAM, REDUCE-2, SYMBAL, CAMAL, AVTO-ANALITIK which are implemented or will be implemented in JINR, and MACSYMA - one of the most developed systems - are discussed. It is shown on the basis of mathematical operations, realized in these systems, that they are appropriated for different problems of theoretical physics and mathematics, for example, for problems of quantum field theory, celestial mechanics, general relativity and so on. Some problems solved in JINR by programming systems for analytical computations are described. The review is intended for specialists in different fields of theoretical physics and mathematics
Physical model and calculation code for fuel coolant interactions
Goldammer, H.; Kottowski, H.
1976-01-01
A physical model is proposed to describe fuel coolant interactions in shock-tube geometry. According to the experimental results, an interaction model which divides each cycle into three phases is proposed. The first phase is the fuel-coolant-contact, the second one is the ejection and recently of the coolant, and the third phase is the impact and fragmentation. Physical background of these phases are illustrated in the first part of this paper. Mathematical expressions of the model are exposed in the second part. A principal feature of the computational method is the consistent application of the fourier-equation throughout the whole interaction process. The results of some calculations, performed for different conditions are compiled in attached figures. (Aoki, K.)
Uncertainty quantification in lattice QCD calculations for nuclear physics
Beane, Silas R. [Univ. of Washington, Seattle, WA (United States); Detmold, William [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Orginos, Kostas [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Savage, Martin J. [Institute for Nuclear Theory, Seattle, WA (United States)
2015-02-05
The numerical technique of Lattice QCD holds the promise of connecting the nuclear forces, nuclei, the spectrum and structure of hadrons, and the properties of matter under extreme conditions with the underlying theory of the strong interactions, quantum chromodynamics. A distinguishing, and thus far unique, feature of this formulation is that all of the associated uncertainties, both statistical and systematic can, in principle, be systematically reduced to any desired precision with sufficient computational and human resources. As a result, we review the sources of uncertainty inherent in Lattice QCD calculations for nuclear physics, and discuss how each is quantified in current efforts.
Calculation of the main neutron parameters of the IEA-R1 research reactor
Ojima, Mario Katsuhiko
1977-01-01
The main neutron parameters of the research reactor IEA-R1 were calculated using computer programs to generate cross sections and criticality calculations. A calculation procedure based on the programs available in the Processing Center Data of IEA was established and centered in the HAMMER and CITATION system. A study was done in order to verify the validity and accuracy of the calculation method comparing the results with experimental data. Some operating parameters of the reactor, namely the distribution of neutron flux, the critical mass, the variation of the reactivity with the burning of fuel, and the dead time of the reactor were determined
Sensitivity of NTCP parameter values against a change of dose calculation algorithm
Brink, Carsten; Berg, Martin; Nielsen, Morten
2007-01-01
Optimization of radiation treatment planning requires estimations of the normal tissue complication probability (NTCP). A number of models exist that estimate NTCP from a calculated dose distribution. Since different dose calculation algorithms use different approximations the dose distributions predicted for a given treatment will in general depend on the algorithm. The purpose of this work is to test whether the optimal NTCP parameter values change significantly when the dose calculation algorithm is changed. The treatment plans for 17 breast cancer patients have retrospectively been recalculated with a collapsed cone algorithm (CC) to compare the NTCP estimates for radiation pneumonitis with those obtained from the clinically used pencil beam algorithm (PB). For the PB calculations the NTCP parameters were taken from previously published values for three different models. For the CC calculations the parameters were fitted to give the same NTCP as for the PB calculations. This paper demonstrates that significant shifts of the NTCP parameter values are observed for three models, comparable in magnitude to the uncertainties of the published parameter values. Thus, it is important to quote the applied dose calculation algorithm when reporting estimates of NTCP parameters in order to ensure correct use of the models
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
Calculation of the level density parameter using semi-classical approach
Canbula, B.; Babacan, H.
2011-01-01
The level density parameters (level density parameter a and energy shift δ) for back-shifted Fermi gas model have been determined for 1136 nuclei for which complete level scheme is available. Level density parameter is calculated by using the semi-classical single particle level density, which can be obtained analytically through spherical harmonic oscillator potential. This method also enables us to analyze the Coulomb potential's effect on the level density parameter. The dependence of this parameter on energy has been also investigated. Another parameter, δ, is determined by fitting of the experimental level scheme and the average resonance spacings for 289 nuclei. Only level scheme is used for optimization procedure for remaining 847 nuclei. Level densities for some nuclei have been calculated by using these parameter values. Obtained results have been compared with the experimental level scheme and the resonance spacing data.
Estimation of Physical Parameters in Linear and Nonlinear Dynamic Systems
Knudsen, Morten
variance and confidence ellipsoid is demonstrated. The relation is based on a new theorem on maxima of an ellipsoid. The procedure for input signal design and physical parameter estimation is tested on a number of examples, linear as well as nonlinear and simulated as well as real processes, and it appears...
The Comparison of Some Physical and Physiological Parameters of Footballers
Ekinci, Ezgi Samar; Beyleroglu, Malik; Ulukan, Hasan; Konuklar, Ercan; Gürkan, Alper Cenk; Erbay, Adem
2016-01-01
In this study, it's to aim for comparison of some physical and physiological parameters of footballers at "The Erenler Sport Team" and "Didim Municipality Sport Team". Thirty volunteers sportsman from each two teams joined to this research. It measured the values of age, weight, length, flexibility, balance, power of left-right…
Calculation of parameters of radial-piston reducer based on the use of functional semantic networks
Pashkevich V.M.
2016-12-01
Full Text Available The questions of сalculation of parameters of radial-piston reducer are considered in this article. It is used the approach which is based technologies of functional semantic networks. It is considered possibility applications of functional se-mantic networks for calculation of parameters of radial-piston reducer. Semantic networks to calculate the mass of the radial piston reducer are given.
Carlen, Ida; Nikolopoulos, Anna; Isaeus, Martin (AquaBiota Water Research, Stockholm (SE))
2007-06-15
GIS grids (maps) of marine parameters were created using point data from previous site investigations in the Forsmark and Oskarshamn areas. The proportion of global radiation reaching the sea bottom in Forsmark and Oskarshamn was calculated in ArcView, using Secchi depth measurements and the digital elevation models for the respective area. The number of days per year when the incoming light exceeds 5 MJ/m2 at the bottom was then calculated using the result of the previous calculations together with measured global radiation. Existing modelled grid-point data on bottom and pelagic temperature for Forsmark were interpolated to create surface covering grids. Bottom and pelagic temperature grids for Oskarshamn were calculated using point measurements to achieve yearly averages for a few points and then using regressions with existing grids to create new maps. Phytoplankton primary production in Forsmark was calculated using point measurements of chlorophyll and irradiance, and a regression with a modelled grid of Secchi depth. Distribution of biomass of macrophyte communities in Forsmark and Oskarshamn was calculated using spatial modelling in GRASP, based on field data from previous surveys. Physical parameters such as those described above were used as predictor variables. Distribution of biomass of different functional groups of fish in Forsmark was calculated using spatial modelling based on previous surveys and with predictor variables such as physical parameters and results from macrophyte modelling. All results are presented as maps in the report. The quality of the modelled predictions varies as a consequence of the quality and amount of the input data, the ecology and knowledge of the predicted phenomena, and by the modelling technique used. A substantial part of the variation is not described by the models, which should be expected for biological modelling. Therefore, the resulting grids should be used with caution and with this uncertainty kept in mind. All
Carlen, Ida; Nikolopoulos, Anna; Isaeus, Martin
2007-06-01
GIS grids (maps) of marine parameters were created using point data from previous site investigations in the Forsmark and Oskarshamn areas. The proportion of global radiation reaching the sea bottom in Forsmark and Oskarshamn was calculated in ArcView, using Secchi depth measurements and the digital elevation models for the respective area. The number of days per year when the incoming light exceeds 5 MJ/m2 at the bottom was then calculated using the result of the previous calculations together with measured global radiation. Existing modelled grid-point data on bottom and pelagic temperature for Forsmark were interpolated to create surface covering grids. Bottom and pelagic temperature grids for Oskarshamn were calculated using point measurements to achieve yearly averages for a few points and then using regressions with existing grids to create new maps. Phytoplankton primary production in Forsmark was calculated using point measurements of chlorophyll and irradiance, and a regression with a modelled grid of Secchi depth. Distribution of biomass of macrophyte communities in Forsmark and Oskarshamn was calculated using spatial modelling in GRASP, based on field data from previous surveys. Physical parameters such as those described above were used as predictor variables. Distribution of biomass of different functional groups of fish in Forsmark was calculated using spatial modelling based on previous surveys and with predictor variables such as physical parameters and results from macrophyte modelling. All results are presented as maps in the report. The quality of the modelled predictions varies as a consequence of the quality and amount of the input data, the ecology and knowledge of the predicted phenomena, and by the modelling technique used. A substantial part of the variation is not described by the models, which should be expected for biological modelling. Therefore, the resulting grids should be used with caution and with this uncertainty kept in mind. All
Study of dose calculation and beam parameters optimization with genetic algorithm in IMRT
Chen Chaomin; Tang Mutao; Zhou Linghong; Lv Qingwen; Wang Zhuoyu; Chen Guangjie
2006-01-01
Objective: To study the construction of dose calculation model and the method of automatic beam parameters selection in IMRT. Methods: The three-dimension convolution dose calculation model of photon was constructed with the methods of Fast Fourier Transform. The objective function based on dose constrain was used to evaluate the fitness of individuals. The beam weights were optimized with genetic algorithm. Results: After 100 iterative analyses, the treatment planning system produced highly conformal and homogeneous dose distributions. Conclusion: the throe-dimension convolution dose calculation model of photon gave more accurate results than the conventional models; genetic algorithm is valid and efficient in IMRT beam parameters optimization. (authors)
Calculation codes in radioprotection, radio-physics and dosimetry
Jan, S.; Laedermann, J.P.; Bochud, F.; Ferragut, A.; Bordy, J.M.; Parisi, L.L.; Abou-Khalil, R.; Longeot, M.; Kitsos, S.; Groetz, J.E.; Villagrasa, C.; Daures, J.; Martin, E.; Henriet, J.; Tsilanizara, A.; Farah, J.; Uyttenhove, W.; Perrot, Y.; De Carlan, L.; Vivier, A.; Kodeli, I.; Sayah, R.; Hadid, L.; Courageot, E.; Fritsch, P.; Davesne, E.; Michel, X.
2010-01-01
anthropo-radiometry (J. Farah); 17 - evaluation of the GUINEVERE experiment shielding (W. Uyttenhove); 18 - GATE/GEANT4 validation for external radiotherapy (Y. Perrot); 19 - European intercomparison of Monte Carlo code users for the kerma uncertainty calculation in air near a 137 Cs source (L. De Carlan); 20 - decision threshold and detection limit in gamma dose rate measurement (A. Vivier); 21 - uncertainties spreading from basic data of nuclear reactors key parameters (I. Kodeli); 22 - evaluation of secondary neutrons-related doses received by patients treated by proton-therapy (R. Sayah); 23 - radioprotection optimization for nuclear medicine patients: doses evaluation for the new reference voxelized fantoms of the CIPR (international commission of radiological protection) (L. Hadid); 24 - radiological accident reconstruction using numerical tools: towards a more and more realistic representation of the victim (E. Courageot); 25 - new tools for treatment optimization after internal contamination by Pu/Am/Cm (P. Fritsch); 26 - development of an expert system for the consideration of uncertainties in internal contamination monitoring (E. Davesne); 27 - CUTADOSE, a calculation code for skin dose estimation after skin contamination (X. Michel). (J.S.)
Pedro L. Valencia
2017-04-01
Full Text Available We provide initial rate data from enzymatic reaction experiments and tis processing to estimate the kinetic parameters from the substrate uncompetitive inhibition equation using the median method published by Eisenthal and Cornish-Bowden (Cornish-Bowden and Eisenthal, 1974; Eisenthal and Cornish-Bowden, 1974. The method was denominated the direct linear plot and consists in the calculation of the median from a dataset of kinetic parameters Vmax and Km from the Michaelis–Menten equation. In this opportunity we present the procedure to applicate the direct linear plot to the substrate uncompetitive inhibition equation; a three-parameter equation. The median method is characterized for its robustness and its insensibility to outlier. The calculations are presented in an Excel datasheet and a computational algorithm was developed in the free software Python. The kinetic parameters of the substrate uncompetitive inhibition equation Vmax, Km and Ks were calculated using three experimental points from the dataset formed by 13 experimental points. All the 286 combinations were calculated. The dataset of kinetic parameters resulting from this combinatorial was used to calculate the median which corresponds to the statistic estimator of the real kinetic parameters. A comparative statistical analyses between the median method and the least squares was published in Valencia et al. [3].
Plasma Physics Calculations on a Parallel Macintosh Cluster
Decyk, Viktor; Dauger, Dean; Kokelaar, Pieter
2000-03-01
We have constructed a parallel cluster consisting of 16 Apple Macintosh G3 computers running the MacOS, and achieved very good performance on numerically intensive, parallel plasma particle-in-cell simulations. A subset of the MPI message-passing library was implemented in Fortran77 and C. This library enabled us to port code, without modification, from other parallel processors to the Macintosh cluster. For large problems where message packets are large and relatively few in number, performance of 50-150 MFlops/node is possible, depending on the problem. This is fast enough that 3D calculations can be routinely done. Unlike Unix-based clusters, no special expertise in operating systems is required to build and run the cluster. Full details are available on our web site: http://exodus.physics.ucla.edu/appleseed/.
Physics methods for calculating light water reactor increased performances
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
Dodoo, Ambrose; Tettey, Uniben Yao Ayikoe; Gustavsson, Leif
2017-01-01
In this study, we modelled the influence of different simulation assumptions on energy balances of two variants of a residential building, comprising the building in its existing state and with energy-efficient improvements. We explored how selected parameter combinations and variations affect the energy balances of the building configurations. The selected parameters encompass outdoor microclimate, building thermal envelope and household electrical equipment including technical installations. Our modelling takes into account hourly as well as seasonal profiles of different internal heat gains. The results suggest that the impact of parameter interactions on calculated space heating of buildings is somewhat small and relatively more noticeable for an energy-efficient building in contrast to a conventional building. We find that the influence of parameters combinations is more apparent as more individual parameters are varied. The simulations show that a building's calculated space heating demand is significantly influenced by how heat gains from electrical equipment are modelled. For the analyzed building versions, calculated final energy for space heating differs by 9–14 kWh/m"2 depending on the assumed energy efficiency level for electrical equipment. The influence of electrical equipment on calculated final space heating is proportionally more significant for an energy-efficient building compared to a conventional building. This study shows the influence of different simulation assumptions and parameter combinations when varied simultaneously. - Highlights: • Energy balances are modelled for conventional and efficient variants of a building. • Influence of assumptions and parameter combinations and variations are explored. • Parameter interactions influence is apparent as more single parameters are varied. • Calculated space heating demand is notably affected by how heat gains are modelled.
Calculation of hadronic transition amplitudes in charm physics
Klein, Christoph
2011-01-01
Transitions of charmed hadrons are of significant importance, since they provide possibilities to extract the CKM matrix elements V cd and V cs from experimental data as well as interesting channels to search for new physics effects. However, quarks are bound in hadrons, and it is necessary to describe this effect in a reliable way, to study the underlying flavour dynamics. For this, one has to use nonperturbative tools, to determine the corresponding transition amplitudes. The results of such calculations can furthermore be of use, to test the predictions of QCD and to contribute to a deeper understanding of the structure of hadrons. In this thesis two topics are investigated using the method of QCD light-cone sum rules (LCSRs). The first topic consists in the form factors of the semileptonic decays D → πlν l and D → Klν l , for which new results are calculated using up-to-date input values. Since LCSRs are not applicable in the whole range of kinematics, they are extrapolated by the use of appropriate parametrisations and the results agree well with experimental data. The second topic are the transitions of charmed baryons to a nucleon. Here the corresponding transition form factors and in addition the hadronic Λ c D (*) N and Σ c D (*) N coupling constants are calculated - the latter by the consideration of double dispersion relations. These coupling constants are of special interest for the description of hadronic interactions, like open charm production in proton-antiprotoncollisions. Furthermore there appears the problem, that both parity states of a baryon contribute to the considered functional representation, for which a consistent way to separate them is presented. (orig.)
An optimization method for parameters in reactor nuclear physics
Jachic, J.
1982-01-01
An optimization method for two basic problems of Reactor Physics was developed. The first is the optimization of a plutonium critical mass and the bruding ratio for fast reactors in function of the radial enrichment distribution of the fuel used as control parameter. The second is the maximization of the generation and the plutonium burnup by an optimization of power temporal distribution. (E.G.) [pt
Japiassu, Fernando Parois
2013-01-01
When designing radiotherapy treatment rooms, the dimensions of barriers are established on the basis of American calculation methodologies specifically; NCRP Report N° 49, NCRP Report N° 51, and more recently, NCRP Report N° 151. Such barrier calculations are based on parameters reflecting predictions of treatments to be performed within the room; which, in tum, reftect a specific reality found in a country. There exists, however, a variety of modern radiotherapy techniques, such as Intensity Modulated Radiation Therapy (IMRT); Total Body Irradiation (TBl) and radiosurgery (SRS); where patierits are treated in a much different way than during more conventional treatrnents, which are not taken into account the traditional shielding calculation methodology. This may lead to a faulty design of treattnent rooms. In order to establish a comparison between the methodology used to calculate shielding design and the reality of treatments performed in Brazil, two radiotherapy facilitie were selected, both of them offering traditional and modern treatment techniqued as described above. Data in relation with reatments perfotmed over a period of six (6)months of operations in both institutions were collected. Based on tlis informaton, a new set of realistic parameters required for shielding design was estãblished, whicb in turn allowed for a nwe caculation of barrier thickness for both facilities. The barrier thickness resultaing from this calculation was then compared with the barrier thickness propose as part of the original shielding design, approved by the regulatory authority. First, concerning the public facility, the thickness of all primary barriers proposed in the shielding design was actually larger than the thickness resulting from calculations based on realistic parameters. Second, concerning the private facility, the new data show that the thickness of three out of the four primary barriers described in the project is larger than the thickness oresulting from
Image quality - physical and diagnostic parameters. The radiologist's viewpoint
Stender, H.St.
1985-01-01
The quality of a radiograph is determined by the diagnostic information it provides. This depends upon the visual detection of diagnostically relevant structures. The technical radiographic requirements are dependent upon the physical measurements and the physiological and optical conditions. Such physical factors as spatial resolution, contrast and noise are quantitative measurements, which must be oriented to the qualitative visual characteristics of the radiograph. The influence of subjective perception and complexity of structural noise on the detectability of details and structures particularly demands attention. Since radiographic quality depends upon the detection of diagnostically relevant structure and features, it is important to define these parameters on the basis of extensive radiographic analysis and the corresponding clinical findings. The diagnostically relevant radiographic parameters and image details and critical structures have been worked out for the examination of the lungs, colon, stomach, urinary tract and skeleton. Good image quality requires coordination of the physical-technical parameters with the visual ability of the observer, since only in this way can the diagnostic information be represented with sufficient clarity. (author)
Calculation uncertainty of distribution-like parameters in NPP of PAKS
Szecsenyi, Zsolt; Korpas, Layos
2000-01-01
In the reactor-physical point of view there were two important events in the Nuclear Power Plant of PAKS in this year. The Russian type profiled assemblies were loaded into the PAKS Unit 3, and new limitation system was introduced on the same Unit. It was required to solve a lot of problems because of these both events. One of these problems was the determination of uncertainty of quantities of the new limitation considering the fabrication uncertainties for the profiled assembly. The importance of determination of uncertainty is to guarantee on 99.9% level the avoidance of fuel failure. In this paper the principles of determination of calculation accuracy, applied methods and obtained results are presented in case of distribution-like parameters. A few elements of the method have been presented on earlier symposiums, so in this paper the whole method is just outlined. For example the GPT method was presented in the following paper: Uncertainty analysis of pin wise power distribution of WWER-440 assembly considering fabrication uncertainties. Finally in the summary of this paper additional intrinsic opportunities in the method are presented. (Authors)
Amirkhizi, Alireza V; Nemat-Nasser, Sia
2008-01-01
Through the use of conductive straight wires or coils the electromagnetic properties of a composite material can be modified. The asymmetric geometry of the coils creates an overall chiral response. The polarization vectors rotate as an electromagnetic wave travels through such a medium. To calculate the chirality of a medium prior to its manufacturing, we developed a method to extract all four electromagnetic material parameter tensors for a general uniaxial bianisotropic composite based on the numerical simulation of the electromagnetic fields. Our method uses appropriate line and surface field averages in a single unit cell of the periodic structure of the composite material. These overall field quantities have physical meaning only when the microscopic variation of the electromagnetic fields in the scale of the unit cell is not important, that is when the wavelength of interest is significantly larger than the maximum linear dimension of the unit cell. The overall constitutive relations of the periodic structure can then be obtained from the relations among the average quantities
Methodology and results of investigations of physical parameters of high-temperature reactors
Cherepnin, Yu.S.; Chertkov, Yu.B.
1995-01-01
A physical investigations of reactors of stand complexes Baikal-1 and IGR have been carrying out more 30 years. Measuring methods of the physical investigations were divided into 2 groups: 1) methods for measuring of reactivity effects; 2) methods for measuring relative and absolute values of neutron flux and power release. The physical investigations on the reactors IVG-1 and IGR were carryied out under following conditions: during physical starts-up of regular variants of reactor cores; during energy starts-up of the reactors; before beginning of new loop chanel tests of the reactors; during research hot starts-up of the reactors the physical parameters were controled. The most full and authentic information about studied reactor have been providing by physical investigations. In 1984 physical investigations were carryied out on the IGR reactor and then the hot start-up of the mostest power and mostest large on fuel loading loop chanel was carryied out. This chanel contained 6 fuel assemblies with the summary fuel loading 3,06 kilogrammes of uranium and it was calculated for power equal to 20 MW. In 1988 the physical investigations for selection of project process chanels destined for new water cooled reactor core were carryied out. In 1993 the neutron-physical calculation on possibility of tests for the rector Nerva fuel element was carryied out. 9 refs., 4 figs
Monte Carlo simulation of core physics parameters of the Syrian MNSR reactor
Khattab, K.; Sulieman, I.
2011-01-01
A 3-D neutronic model for the Syrian Miniature Neutron Source Reactor (MNSR) was developed earlier to conduct the reactor neutronic analysis using the MCNP-4C code. The continuous energy neutron cross sections were evaluated from the ENDF/B-VI library. This model is used in this paper to calculate the following reactor core physics parameters: the clean cold core excess reactivity, calibration of the control rod and calculation its shut down margin, calibration of the top beryllium shim plate reflector, the axial neutron flux distributions in the inner and outer irradiation positions and calculations of the prompt neutron life time (ι p ) and the effective delayed neutron fraction ( β e ff). Good agreements are noticed between the calculated and the measured results. These agreements indicate that the established model is an accurate representation of Syrian MNSR core and will be used for other calculations in the future. (author)
Artemov, V.G.; Gusev, V.I.; Zinatullin, R.E.; Karpov, A.S.
2007-01-01
Using modeled WWER cram rod drop experiments, performed at the Rostov NPP, as an example, the influence of delayed neutron parameters on the modeling results was investigated. The delayed neutron parameter values were taken from both domestic and foreign nuclear databases. Numerical modeling was carried out on the basis of SAPFIR 9 5andWWERrogram package. Parameters of delayed neutrons were acquired from ENDF/B-VI and BNAB-78 validated data files. It was demonstrated that using delay fraction data from different databases in reactivity meters led to significantly different reactivity results. Based on the results of numerically modeled experiments, delayed neutron parameters providing the best agreement between calculated and measured data were selected and recommended for use in reactor calculations (Authors)
Viais J, J.
1994-01-01
Kinetic parameters for dynamic study of two different configurations, 8 and 9, both with standard fuel, 20% enrichment and Flip (Fuel Life Improvement Program with 70% enrichment) fuel, for TRIGA Mark-III reactor from Mexico Nuclear Center, are obtained. A calculation method using both WIMS-D4 and DTF-IV and DAC1 was established, to decide which of those two configurations has the best safety and operational conditions. Validation of this methodology is done by calculate those parameters for a reactor core with new standard fuel. Configuration 9 is recommended to be use. (Author)
Distribution and Parameter's Calculations of Television Cameras Inside a Nuclear Facility
El-kafas, A.A.
2009-01-01
In this work, a distribution of television cameras and parameter's calculation inside and outside a nuclear facility is presented. Each of exterior and interior camera systems will be described and explained. The work shows the overall closed circuit television system. Fixed and moving cameras with various lens format and different angles of view are used. The calculations of width of images sensitive area and Lens focal length for the cameras will be introduced. The work shows the camera locations and distributions inside and outside the nuclear facility. The technical specifications and parameters for cameras selection are tabulated
Frolov, A.M.
1986-01-01
The problem of exact variational calculations of few-particle systems in the exponential basis of the relative coordinates using nonlinear parameters is studied. The techniques of stepwise optimization and global chaos of nonlinear parameters are used to calculate the S and P states of homonuclear muonic molecules with an error of no more than +0.001 eV. The global-chaos technique also has proved to be successful in the case of the nuclear systems 3 H and 3 He
Using Cut-off grade isograms to delineate ore body and calculate parameter
Yu Yongfeng; Zhu Xiaobing; Deng Yonghui
2014-01-01
Taking a uranium mine for an example, using cut-off grade isograms to achieve automatic delineation of ore body and calculation of parameters are explored. With center line of catalog sampling as baseline, the number of sampling and length of sampling constructing rectangular grid and grade as elevation value, isograms of cut-off grade were drawn, thus achieving the delineation of the ore body. Then, the other parameters of the ore body can be calculated. Compared with the traditional hand drawing method, the work efficiency was greatly improved, and the material inquiry was more convenient. (authors)
Duran, I; Martinez-Laso, L
1989-07-01
We present here the methods we used to analyse the characteristic parameters of drift chambers. The algorithms to calculate the electric potential in any point for any drift chamber geometry are presented. We include the description of the programs used to calculate the electric field, the drift paths, the drift velocity and the drift time. The results and the errors are discussed. (Author) 7 refs.
CASIM calculations and angular dependent parameter β in the Moyer model
Yamaguchi, Chiri.
1988-04-01
The dose equivalent on the shield surface has been calculated using both the Moyer model and the Monte Carlo code CASIM. Calculations with various values of the angular distribution parameter β in the Moyer model show that β = 7.0 ± 0.5 would meet the CASIM results at most, especially regarding locations at which the values of the maximum dose equivalent occur. (author)
Gueclue, M.C.
2000-01-01
We provide a new general semi-analytic derivation of the impact parameter dependence of lowest order electromagnetic lepton-pair production in relativistic heavy-ion collisions. By using this result we have also calculated the related analytic multiple-pair production in the two-photon external-field model. We have compared our results with the equivalent-photon approximation and other calculations
Kinetic parameters evaluation of PWRs using static cell and core calculation codes
Jahanbin, Ali; Malmir, Hessam
2012-01-01
Highlights: ► In this study, we have calculated effective delayed neutron fraction and prompt neutron lifetime in PWRs. ► New software has been developed to link the WIMS, BORGES and CITATION codes in Visual C computer programming language. ► This software is used for calculation of the kinetic parameters in a typical VVER-1000 and NOK Beznau reactor. ► The ratios ((β eff ) i )/((β eff ) core ) , which are the important input data for the reactivity accident analysis, are also calculated. - Abstract: In this paper, evaluation of the kinetic parameters (effective delayed neutron fraction and prompt neutron lifetime) in PWRs, using static cell and core calculation codes, is reported. A new software has been developed to link the WIMS, BORGES and CITATION codes in Visual C computer programming language. Using the WIMS cell calculation code, multigroup microscopic cross-sections and number densities of different materials can be generated in a binary file. By the use of BORGES code, these binary-form cross-sections and number densities are converted to a format readable by the CITATION core calculation code, by which the kinetic parameters can be finally obtained. This software is used for calculation of the kinetic parameters in a typical VVER-1000 and NOK Beznau reactor. The ratios ((β eff ) i )/((β eff ) core ) , which are the important input data for the reactivity accident analysis, are also calculated. Benchmarking of the results against the final safety analysis report (FSAR) of the aforementioned reactors shows very good agreements with these published documents.
Hyperfine electric parameters calculation in Si samples irradiated with 57Mn
Abreu, Y.; Cruz, C. M.; Pinnera, I.; Leyva, A.; Van Espen, P.; Perez, C.
2011-01-01
The radiation damage created in silicon crystalline material by 57 Mn→ 57 Fe ion implantation was characterized by Moessbauer spectroscopy showing three main lines, assigned to: substitutional, interstitial and a damage configuration sites of the implanted ions. The hyperfine electric parameters, Quadrupole Splitting and Isomer Shift, were calculated for various implantation environments. In the calculations the full potential linearized-augmented plane-wave plus local orbitals (L/APW+lo) method as embodied in the WIEN2k code was used. Good agreement was found between the experimental and the calculated values for some implantation configurations; suggesting that the implantation environments could be similar to the ones proposed by the authors. (Author)
Kripal, Ram, E-mail: ram_kripal2001@rediffmail.com; Yadav, Awadhesh Kumar, E-mail: aky.physics@gmail.com
2015-06-15
Zero field splitting parameters (ZFSPs) D and E of Cr{sup 3+} ion doped ammonium oxalate monohydrate (AOM) are calculated with formula using the superposition model. The theoretically calculated ZFSPs for Cr{sup 3+} in AOM crystal are compared with the experimental value obtained by electron paramagnetic resonance (EPR). Theoretical ZFSPs are in good agreement with the experimental ones. The energy band positions of optical absorption spectra of Cr{sup 3+} in AOM crystal calculated with CFA package are in good match with the experimental values.
A benchmark test of computer codes for calculating average resonance parameters
Ribon, P.; Thompson, A.
1983-01-01
A set of resonance parameters has been generated from known, but secret, average values; the parameters have then been adjusted to mimic experimental data by including the effects of Doppler broadening, resolution broadening and statistical fluctuations. Average parameters calculated from the dataset by various computer codes are compared with each other, and also with the true values. The benchmark test is fully described in the report NEANDC160-U (NEA Data Bank Newsletter No. 27 July 1982); the present paper is a summary of this document. (Auth.)
Antunes, Alberi
2008-01-01
This work presents the Physics of Source Driven Systems (ADS). It shows some statics and K i netics parameters of the reactor Physics and when it is sub critical, that are important in evaluation and definition of these systems. The objective is to demonstrate that there are differences in parameters when the reactor is critical. Moreover, the work shows the differences observed in the parameters for different calculation models. Two calculation methodologies are shown In this dissertation: Gandini and Salvatores and Dulla, and some parameters are calculated. The ANISN deterministic transport code is used in calculation in order to compare these parameters. In a subcritical configuration of IPEN-MB-01 Reactor driven by an external source some parameters are calculated. The conclusions about calculation realized are presented in end of work. (author)
Global and photospheric physical parameters of active dwarf stars
Pettersen, B.R.
1983-01-01
Physical parameters (temperature, luminosity, radius, mass and chemical abundance) of the photospheres of red dwarf flare stars and spotted stars are determined for quiescent conditions. The interrelations between these quantities are compared to the results of theoretical investigation for low mass stars. The evolutionary state of flare stars is discussed. Observational results from spectroscopic and photometric methods to determine the rotation of active dwarfs are reviewed. The possibilities of global oscillations in dwarf stars are considered and preliminary results of a photometric search for oscillation in red dwarf luminosities are presented. (orig.)
First-principles calculations of Moessbauer hyperfine parameters for solids and large molecules
Guenzburger, Diana [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Ellis, D.E. [Northwestern Univ., Evanston, IL (United States). Dept. of Physics; Zeng, Z. [Academia Sinica, Hefei, AH (China). Inst. of Solid-State Physics
1997-10-01
Electronic structure calculations based on Density Functional theory were performed for solids and large molecules. The solids were represented by clusters of 60-100 atoms embedded in the potential of the external crystal. Magnetic moments and Moessbauer hyperfine parameters were derived. (author) 22 refs., 8 figs., 1 tab.
First-principles calculations of Moessbauer hyperfine parameters for solids and large molecules
Guenzburger, Diana; Ellis, D.E.; Zeng, Z.
1997-10-01
Electronic structure calculations based on Density Functional theory were performed for solids and large molecules. The solids were represented by clusters of 60-100 atoms embedded in the potential of the external crystal. Magnetic moments and Moessbauer hyperfine parameters were derived. (author)
Ab inito calculations of Hubbard parameters for NiO and Gd crystals
A. R Faghihi and S Jalali Asadabadi
2008-07-01
Full Text Available In this research the Hubbard parameters have been calculated for NiO and Gd crystals, as two strongly correlated systems with partially full 3d and 4f levels, respectively. The calculations were performed within the density functional theory (DFT using the augmented plane waves plus the local orbitat (APW+lo method. We constructed a suitable supercell and found that the Hubbard parameters for the NiO and Gd compounds are equal to 5.9 eV and 5.7 eV, respectively. Our results are in good agreement with experimental data and results of other computational methods. Then we used the obtained parameters to study the structural properties of NiO and Gd by means of LDA+U approximation. Our results calculated by the LDA+U method which are in better agreement with the experiment show a significant improvement compared to the GGA approximation. The result shows that our method for calculating U parameter can be considered as a satisfactory method to study a strongly correlated system.
Analytical model for calculation of the thermo hydraulic parameters in a fuel rod assembly
Cesna, B., E-mail: benas@mail.lei.l [Lithuanian Energy Institute, Laboratory of Nuclear Installation Safety, Breslaujos g. 3, LT-44403 Kaunas (Lithuania)
2010-11-15
Research highlights: {yields} Proposed calculation model can be used for rapid calculation of the bundles with rods spaced by wire wrapping or honey type spacer grids. {yields} Model estimate three flow cross mixture mechanisms. {yields} Program DARS is enable to analyses experimental results. - Abstract: The paper presents the procedure of the cellular calculation of thermo hydraulic parameters of a single-phase gas flow in a fuel rod assembly. The procedure is implemented in the DARS program. The program is intended for calculation of the distribution of the gaseous coolant parameters and wall temperatures in case of arbitrary, geometrically specified, arrangement of the rods in fuel assembly and in case of arbitrary, functionally specified in space, heat release in the rods. In mathematical model the flow cross-section of the channel of intricate shape is conventionally divided to elementary cells formed by straight lines, which connect the centers of rods. Within the limits of a single cell the coolant parameters and the temperature of the corresponding part of the rod surface are assumed constant. The entire fuel assembly is viewed as a system of parallel interconnected channels. Program DARS is illustrated by calculation of a temperature mode of 85-rod assembly with spacers of wire wrapping on the rods.
Pre- and post- test calculation for the parameter-SF1 experiment with ATHLET-CD
Erdmann, W.; Trambauer, K.; Stuckert, J. [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koln (Germany)
2006-07-01
The main objective of the PARAMETER-SF1 experiment in the frame of the ISTC project 3194 is the experimental and analytical investigation of the Russian VVER-1000 fuel rod assemblies behavior under simulated conditions of a severe accident. The special feature is to study the effect of flooding a superheated test bundle from the top (top quenching) which has not yet been investigated at all. - Simulation of the PARAMETER test facility To calculate the special effects of the top quenching, some aspects are important: detailed simulation of the bundle top, top and bottom quench front, heat losses at top/bottom of bundle, electrical heater power. - Main initial and boundary conditions The proposed initial and boundary conditions for the double-blind pre-test calculation were quite different from the actual experimental data during the test e.g.: electric power, mass flow (water, steam, argon), temperature. - Conclusions: first experiment with top flooding proposed initial condition given in the specification could not be performed during the experiment, bundle parameters deviated from anticipated values, thus, the pre-calculations not comparable with the experiment, post-calculations with ATHLET-CD showed good agreement with experiment data, top flooding is well predicted, calculational results sensitive with respect to: boundary conditions, nodalization. (authors)
Calculation of electron-beam induced displacement in thin films by using parameter-reduced formulas
Yan, Qiang [College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001 (China); Chen, Di [Department of Nuclear Engineering, Texas A& M University, College Station, TX 77843 (United States); Wang, Qingyu; Li, Zhongyu [College of Nuclear Science and Technology, Harbin Engineering University, Harbin 150001 (China); Shao, Lin, E-mail: lshao@tamu.edu [Department of Nuclear Engineering, Texas A& M University, College Station, TX 77843 (United States)
2017-03-01
Based on the Mott cross sections of relativistic electron collisions with atoms, we calculate displacement creation by electron beams of arbitrary energies (up to 100 MeV) in thin films of arbitrary atomic numbers (up to Z = 90). In a comparison with Mont Carlo full damage cascade simulations, we find that total number of displacements in a film can be accurately estimated as the product of average displacements created per collision and average collision numbers in the film. To calculate average displacements per electron-atom collision, energy transfer from Mott cross section is combined with NRT model. To calculate collision numbers, mean deflection angles and multi-scattering theory are combined to extract collision number dependence on film thickness. For each key parameter, parameter-reduced formulas are obtained from data fitting. The fitting formulas provide a quick and accurate method to estimate radiation damage caused by electron beams.
Kljenak, I.; Mavko, B.; Babic, M.
2005-01-01
Full text of publication follows: The modelling and simulation of atmosphere mixing and stratification in nuclear power plant containments is a topic, which is currently being intensely investigated. With the increase of computer power, it has now become possible to model these phenomena with a local instantaneous description, using so-called Computational Fluid Dynamics (CFD) codes. However, calculations with these codes still take relatively long times. An alternative faster approach, which is also being applied, is to model nonhomogeneous atmosphere with lumped-parameter codes by dividing larger control volumes into smaller volumes, in which conditions are modelled as homogeneous. The flow between smaller volumes is modelled using one-dimensional approaches, which includes the prescription of flow loss coefficients. However, some authors have questioned this approach, as it appears that atmosphere stratification may sometimes be well simulated only by adjusting flow loss coefficients to adequate 'artificial' values that are case-dependent. To start the resolution of this issue, a modelling of nonhomogeneous atmosphere with a lumped-parameter code is proposed, where the subdivision of a large volume into smaller volumes is based on results of CFD simulations. The basic idea is to use the results of a CFD simulation to define regions, in which the flow velocities have roughly the same direction. These regions are then modelled as control volumes in a lumped-parameter model. In the proposed work, this procedure was applied to a simulation of an experiment of atmosphere mixing and stratification, which was performed in the TOSQAN facility. The facility is located at the Institut de Radioprotection et de Surete Nucleaire (IRSN) in Saclay (France) and consists of a cylindrical vessel (volume: 7 m3), in which gases are injected. In the experiment, which was also proposed for the OECD/NEA International Standard Problem No.47, air was initially present in the vessel, and
Hyperfine electric parameters calculation in Si samples implanted with {sup 57}Mn→{sup 57}Fe
Abreu, Y., E-mail: yabreu@ceaden.edu.cu [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Calle 30 No. 502 e/5ta y 7ma Ave., 11300 Miramar, Playa, La Habana (Cuba); Cruz, C.M.; Piñera, I.; Leyva, A.; Cabal, A.E. [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Calle 30 No. 502 e/5ta y 7ma Ave., 11300 Miramar, Playa, La Habana (Cuba); Van Espen, P. [Departement Chemie, Universiteit Antwerpen, Middelheimcampus, G.V.130, Groenenborgerlaan 171, 2020 Antwerpen (Belgium); Van Remortel, N. [Departement Fysica, Universiteit Antwerpen, Middelheimcampus, G.U.236, Groenenborgerlaan 171, 2020 Antwerpen (Belgium)
2014-07-15
Nowadays the electronic structure calculations allow the study of complex systems determining the hyperfine parameters measured at a probe atom, including the presence of crystalline defects. The hyperfine electric parameters have been measured by Mössbauer spectroscopy in silicon materials implanted with {sup 57}Mn→{sup 57}Fe ions, observing four main contributions to the spectra. Nevertheless, some ambiguities still remain in the {sup 57}Fe Mössbauer spectra interpretation in this case, regarding the damage configurations and its evolution with annealing. In the present work several implantation environments are evaluated and the {sup 57}Fe hyperfine parameters are calculated. The observed correlation among the studied local environments and the experimental observations is presented, and a tentative microscopic description of the behavior and thermal evolution of the characteristic defects local environments of the probe atoms concerning the location of vacancies and interstitial Si in the neighborhood of {sup 57}Fe ions in substitutional and interstitial sites is proposed.
Calculation of the major material parameters of heat carriers for cryogenic heat pipes
Molt, W.
1976-07-01
In order to make predictions on the efficiency of cryogenic heat pipes, the material parameters of the heat carrier such as surface tension, viscosity, evaporation heat and density of the liquid should be known. The author therefore investigates suitable interpolation methods and equations which enable the calculation of the desired material parameter at a certain temperature from other known quantities or which require that 1 to 3 material parameters at different temperatures are known. The calculations are limited to the temperature between critical temperature and triple point, since this is the only temperature region in which the heat carrier is in its liquid phase. The applicability and exactness of the equations is tested using known experimental data on N 2 , O 2 , CH 4 and partly on CF 4 . (orig./TK) [de
Migliavacca, S.C.P.
1991-01-01
A review of the isotope separation theory for the countercurrent gas centrifuge is presented. The diffusion-convection equation is solved according to the ONSAGER-COHEN solution for the constant internal flow and adapted to an axially varying countercurrent flow. Based on that theory, a numerical program is developed for the calculation of the isotopic compositions and the separative parameters of the centrifuge. The influence of the feed flow and the internal parameters. Like cut and countercurrent flow, on the separative parameters is then analysed for a model-centrifuge, which afterwards is optimized with respect to its separative power. Finally, a comparison between the present calculation procedure and some published results, provided by different theories, shows deviations lower then 20%. (author)
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)
Sone, Kazuho; Shiraishi, Kensuke
1975-04-01
The depth distribution of displacement damage expressed in displacements per atom (DPA) in reactor materials such as Mo, Nb, V, Fe and Ni bombarded by energetic nitrogen, argon and self ions with incident energy below 2 MeV was calculated following the theory developed by Lindhard and co-workers for the partition of energy as an energetic ion slowing down. In this calculation, energy loss due to electron excitation was taken into account for the atomic collision cascade after the primary knock-on process. Some parameters indispensable for the calculation such as energy loss rate, damage efficiency, projected range and its straggling were tabulated as a function of incident ion energy of 20 keV to 2 MeV. The damage and parameters were also calculated for 2 MeV nickel ions bombarding Fe targets. In this case, the DPA value is of 40--75% overestimated in a calculation disregarding electronic energy loss for primary knock-on atoms. The formula proposed in this report is significant for calculations on displacement damage produced by heavy ion bombardment as a simulation of high fluence fast neutron damage. (auth.)
Sone, K; Shiraishi, K
1975-04-01
The depth distribution of displacement damage expressed in displacements per atom (DPA) in reactor materials such as Mo, Nb, V, Fe and Ni bombarded by energetic nitrogen, argon and self ions with incident energy below 2 MeV was calculated following the theory developed by Lindhard and co-workers for the partition of energy as an energetic ion slowing down. In this calculation, energy loss due to electron excitation was taken into account for the atomic collision cascade after the primary knock-on process. Some parameters indispensable for the calculation such as energy loss rate, damage efficiency, projected range and its straggling were tabulated as a function of incident ion energy of 20 keV to 2 MeV. The damage and parameters were also calculated for 2 MeV nickel ions bombarding Fe targets. In this case, the DPA value is of 40--75% overestimated in a calculation disregarding electronic energy loss for primary knock-on atoms. The formula proposed in this report is significant for calculations on displacement damage produced by heavy ion bombardment as a simulation of high fluence fast neutron damage.
Thermodynamic calculations of self- and hetero-diffusion parameters in germanium
Saltas, V.; Vallianatos, F.
2015-01-01
In the present work, the diffusion coefficients of n- and p-type dopants (P, As, Sb, Al) and self-diffusion in crystalline germanium are calculated from the bulk elastic properties of the host material based on the cBΩ thermodynamic model. The calculated diffusion coefficients as a function of temperature and the activation enthalpies prove to be in full agreement with the reported experimental results. Additional point defect parameters such as activation entropy, activation volume and activation Gibbs free energy are also calculated for each diffusing element. The pressure dependence of self-diffusion coefficients in germanium is also verified at high temperatures (876 K–1086 K), in agreement with reported results ranging from ambient pressure up to 600 MPa and is further calculated at pressures up to 3 GPa, where the phase transition to Ge II occurs. - Highlights: • Calculation of diffusivities of n- and p-type dopants in Ge from elastic properties. • Calculation of point defect parameters according to the cBΩ thermodynamic model. • Prediction of the pressure dependence of self-diffusion coefficients in Ge
Ramounet-le Gall, B.; Fritsch, P.; Abram, M.C.; Rateau, G.; Grillon, G.; Guillet, K.; Baude, S.; Berard, P.; Ansoborlo, E.; Delforge, J.
2002-01-01
A review on specific parameter measurements to calculate doses per unit of incorporation according to recommendations of the International Commission of Radiological Protection has been performed for inhaled actinide oxides. Alpha activity distribution of the particles can be obtained by autoradiography analysis using aerosol sampling filters at the work places. This allows us to characterize granulometric parameters of 'pure' actinide oxides, but complementary analysis by scanning electron microscopy is needed for complex aerosols. Dissolution parameters with their standard deviation are obtained after rat inhalation exposure, taking into account both mechanical lung clearance and actinide transfer to the blood estimated from bone retention. In vitro experiments suggest that the slow dissolution rate might decrease as a function of time following exposure. Dose calculation software packages have been developed to take into account granulometry and dissolution parameters as well as specific physiological parameters of exposed individuals. In the case of poorly soluble actinide oxides, granulometry and physiology appear as the main parameters controlling dose value, whereas dissolution only alters dose distribution. Validation of these software packages are in progress. (author)
ANALYSIS THE DIURNAL VARIATIONS ON SELECTED PHYSICAL AND PHYSIOLOGICAL PARAMETERS
A. MAHABOOBJAN
2010-12-01
Full Text Available The purpose of the study was to analyze the diurnal variations on selected physical and physiological parameters such as speed, explosive power, resting heart rate and breath holding time among college students. To achieve the purpose of this study, a total of twenty players (n=20 from Government Arts College, Salem were selected as subjects To study the diurnal variation of the players on selected physiological and performance variables, the data were collected 4 times a day with every four hours in between the times it from 6.00 to 18.00 hours were selected as another categorical variable. One way repeated measures (ANOVA was used to analyze the data. If the obtained F-ratio was significant, Seheffe’s post-hoc test was used to find out the significant difference if anyamong the paired means. The level of significance was fixed at.05 level. It has concluded that both physical and physiological parameters were significantly deferred with reference to change of temperature in a day
Thermodynamic study of fluid in terms of equation of state containing physical parameters
Khasare, S. B.
2015-01-01
We introduce a simple condition for one mole fluid by considering the thermodynamics of molecules pointing towards the effective potential for the cluster. Efforts are made to estimate new physical parameter f in liquid state using the equation of state containing only two physical parameters such as the hard sphere diameter and binding energy. The temperature dependence of the structural properties and the thermodynamic behavior of the clusters are studied. Computations based on f predict the variation of numbers of particles at the contact point of the molecular cavity (radial distribution function). From the thermodynamic profile of the fluid, the model results are discussed in terms of the cavity due to the closed surface along with suitable energy. The present calculation is based upon the sample thermodynamic data for n-hexanol, such as the ultrasonic wave, density, volume expansion coefficient, and ratio of specific heat in the liquid state, and it is consistent with the thermodynamic relations containing physical parameters such as size and energy. Since the data is restricted to n-hexanol, we avoid giving the physical meaning of f, which is the key parameter studied in the present work. (paper)
Redundant and physical black hole parameters: Is there an independent physical dilaton charge?
K. Hajian
2017-05-01
Full Text Available Black holes as solutions to gravity theories, are generically identified by a set of parameters. Some of these parameters are associated with black hole physical conserved charges, like ADM charges. There can also be some “redundant parameters.” We propose necessary conditions for a parameter to be physical. The conditions are essentially integrability and non-triviality of the charge variations arising from “parametric variations,” variation of the solution with respect to the chosen parameters. In addition, we prove that variation of the redundant parameters which do not meet our criteria do not appear in the first law of thermodynamics. As an interesting application, we show that dilaton moduli are redundant parameters for black hole solutions to Einstein–Maxwell–(Axion–Dilaton theories, because variations in dilaton moduli would render entropy, mass, electric charges or angular momenta non-integrable. Our results are in contrast with modification of the first law due to scalar charges suggested in Gibbons–Kallosh–Kol paper [1] and its follow-ups. We also briefly discuss implications of our results for the attractor behavior of extremal black holes.
Redundant and physical black hole parameters: Is there an independent physical dilaton charge?
Hajian, K., E-mail: kamalhajian@ipm.ir; Sheikh-Jabbari, M.M., E-mail: jabbari@theory.ipm.ac.ir
2017-05-10
Black holes as solutions to gravity theories, are generically identified by a set of parameters. Some of these parameters are associated with black hole physical conserved charges, like ADM charges. There can also be some “redundant parameters.” We propose necessary conditions for a parameter to be physical. The conditions are essentially integrability and non-triviality of the charge variations arising from “parametric variations,” variation of the solution with respect to the chosen parameters. In addition, we prove that variation of the redundant parameters which do not meet our criteria do not appear in the first law of thermodynamics. As an interesting application, we show that dilaton moduli are redundant parameters for black hole solutions to Einstein–Maxwell–(Axion)–Dilaton theories, because variations in dilaton moduli would render entropy, mass, electric charges or angular momenta non-integrable. Our results are in contrast with modification of the first law due to scalar charges suggested in Gibbons–Kallosh–Kol paper and its follow-ups. We also briefly discuss implications of our results for the attractor behavior of extremal black holes.
Calculation of the neutron activation parameters from recently evaluated nuclear data
Lopez Aldama, Daniel; Diaz Martinez, Nereida C.
1999-01-01
Neutron Activation Analysis (NAA) requires the values for nuclear data such as the 2200 m/s cross section so, the resonance integral I0, the parameter Q0 and the well-known Westcott factors. The availability of recently evaluated nuclear data libraries as the ENDF/B-VI Rev. 5, JEF 2.2, CENDL-2.1 and JENDL-3.2, makes possible to derive the above quantities from the basic nuclear data. It could be very helpful for those NAA parameters, which are unknown or difficult to measure accurately. The procedure to compute the NAA parameters includes the processing of the evaluated nuclear data and the calculation of each parameter directly from its definition. The evaluated nuclear data libraries ENDF/B-VI Rev. 5 and JENDL 3.2 were selected as the main sources of basic nuclear data. The ENDF pre-processing codes were used for processing the source evaluated data and a modified version of the INTER code was applied to calculate the required NAA integrals. The NAA parameters were computed for more than 30 important isotopes. The obtained results were compared with experimental values whenever possible
Neutron quality parameters versus energy below 4 MeV from microdosimetric calculations
Stinchcomb, T.G.; Borak, T.B.
1983-01-01
Charged-particle production by neutrons and the resulting energy-deposition spectra in micron-sized spheres of tissue of varying diameters were calculated from thermal energies to 4 MeV. These data were used to obtain dose-average values of several quality-indicating parameters as functions of neutron energy and of tissue sphere diameter. The contrast among the parameters is shown and discussed. Applications are made to two neutron spectra, one a fission spectrum in air and the other a moderated spectrum at the center of an irradiated cube of water
Kawamura, T.; Ono, T.; Yamamura, Y.
1994-08-01
Physical sputtering yields from the carbon surface irradiated by the boundary plasma are obtained with the use of a Monte Carlo simulation code ACAT. The yields are calculated for many random initial energy and angle values of incident protons or deuterons with a Maxwellian velocity distribution, and then averaged. Here the temperature of the boundary plasma, the sheath potential and the angle δ between the magnetic field line and the surface normal are taken into account. A new fitting formula for an arrangement of the numerical data of sputtering yield is introduced, in which six fitting parameters are determined from the numerical results and listed. These results provide a way to estimate the erosion of carbon materials irradiated by boundary plasma. The particle reflection coefficients for deuterons and their neutrals from a carbon surface are also calculated by the same code and presented together with, for comparison, that for the case of monoenergetic normal incidence. (author)
The calculation of some gamma shielding parameters for semiconductor CsPbBr3
Oto, Berna; Gulebaglan, Sinem Erden; Kanberoglu, Gulsah Saydan
2017-02-01
Recently, researchers produced perovskites structures used in optoelectronic devices as substrates, sensors. CsPbBr3 crystal is found in the cubic perovskite structure and its space group is Pm-3m. CsPbBr3 is a developing material for detection of X- and γ-ray radiations and the knowledge of the attenuation parameters of CsPbBr3 crystal is important. In this study, some photon shielding parameters such as mass attenuation coefficient (μρ), effective atomic number (Zeff) and electron density (Nel) have been investigated for CsPbBr3 compound. The theoretical values of μρ have been calculated in the energy range from 1 keV to 100 GeV using WinXCom computer code and these values have been used in order to calculate the values of Zeff and Nel in the same energy range.
Standard model parameters and the search for new physics
Marciano, W.J.
1988-04-01
In these lectures, my aim is to present an up-to-date status report on the standard model and some key tests of electroweak unification. Within that context, I also discuss how and where hints of new physics may emerge. To accomplish those goals, I have organized my presentation as follows: I discuss the standard model parameters with particular emphasis on the gauge coupling constants and vector boson masses. Examples of new physics appendages are also briefly commented on. In addition, because these lectures are intended for students and thus somewhat pedagogical, I have included an appendix on dimensional regularization and a simple computational example that employs that technique. Next, I focus on weak charged current phenomenology. Precision tests of the standard model are described and up-to-date values for the Cabibbo-Kobayashi-Maskawa (CKM) mixing matrix parameters are presented. Constraints implied by those tests for a 4th generation, supersymmetry, extra Z/prime/ bosons, and compositeness are also discussed. I discuss weak neutral current phenomenology and the extraction of sin/sup 2/ /theta//sub W/ from experiment. The results presented there are based on a recently completed global analysis of all existing data. I have chosen to concentrate that discussion on radiative corrections, the effect of a heavy top quark mass, and implications for grand unified theories (GUTS). The potential for further experimental progress is also commented on. I depart from the narrowest version of the standard model and discuss effects of neutrino masses and mixings. I have chosen to concentrate on oscillations, the Mikheyev-Smirnov- Wolfenstein (MSW) effect, and electromagnetic properties of neutrinos. On the latter topic, I will describe some recent work on resonant spin-flavor precession. Finally, I conclude with a prospectus on hopes for the future. 76 refs
Neutronic calculation of safety parameters for the RP-0 and RP-10 nuclear reactors
Lázaro, Gerardo; Deen, James R.; Woodruff, William L.
2002-01-01
Theoretical safety calculations were done with proved codes utilized by the staff of the RERTR program in the HEU to LEU core conversions. The studies were designed to evaluate the reactivity coefficients and kinetics parameters of the reactor involved in the evolution of peak power transients by reactivity insertion accidents. It was done to show the trend of these reactivity coefficients as a function of the core size and fuel depletion for RP10 cores. It was useful to get a better underst...
NERON-Computing system for PHWR reactor cells and heterogeneous parameter calculations
Cristian, I.; Cirstoiu, B.; Slavnicu, S.D.
1976-04-01
A system of codes for PHWR type reactors is presented. The system includes the cell code NERO and a code PARETE for monopolar and dipolar heterogeneous calculations. A general theory of dipolar flux is necessary for a more accurate evaluation of void coefficient and diffusion moderator coefficient is given. The determination of monopolar and dipolar heterogeneous parameters is very useful for heterogeneous methods developped especially for HWR reactors during the last years. (author)
A New Theory for Calculation of Some Biochemical Parameters Concentration in Human Serum
Moustafa, K.A.; Amien, A.I.
2009-01-01
The serum volumes of the blood samples are varied from one patient to another according to the packed cell volume (PCV %), so if the patient sample has low PCV %, it will have high serum volume and vice versa. To calculate a certain clinical parameter such as glucose in the serum of patients using the conventional calculation, it will give the concentration in units per deci liter serum, while by calculating the concentration according to the ratio of serum volume to the total volume of the blood, it will give different results. Thus, the present study aimed to find a new theory used for calculation of some biochemical parameters concentration taking into consideration the ratio of plasma volume to the total blood volume. The present study was conducted on 122 subjects. These subjects were categorized into 4 groups. Group 1 (G1) comprised 40 healthy subjects as control group, group 2 (G2) comprised 30 low PCV % patients, group 3 (G3) comprised 30 subjects with relatively high PCV % and group 4 comprised 22 diabetic patients. Each group of the previous groups was further subdivided into group a (G a ) and group b (G b ). In the later group, the results were multiplied by the correction factor (V p /V b ), which is the ratio of plasma volume (V p ) to the blood volume (V b ) TSH hormone, glucose, cholesterol, triglycerides, urea, creatinine, uric acid, alanine aminotransferase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) were estimated and the results were multiplied by the correction factor (V p /V b ) to get the results after correction. Compared the results before and after correction, there was a very highly significant (ρ p /V b ), thus we recommended that biochemical parameters results must be calculated as indicated in the present study to obtain actual results which might be useful in the correct diagnosis, monitoring and follow up of the different diseases
Analytical calculation of detailed model parameters of cast resin dry-type transformers
Eslamian, M.; Vahidi, B.; Hosseinian, S.H.
2011-01-01
Highlights: → In this paper high frequency behavior of cast resin dry-type transformers was simulated. → Parameters of detailed model were calculated using analytical method and compared with FEM results. → A lab transformer was constructed in order to compare theoretical and experimental results. -- Abstract: Non-flammable characteristic of cast resin dry-type transformers make them suitable for different kind of usages. This paper presents an analytical method of how to obtain parameters of detailed model of these transformers. The calculated parameters are compared and verified with the corresponding FEM results and if it was necessary, correction factors are introduced for modification of the analytical solutions. Transient voltages under full and chopped test impulses are calculated using the obtained detailed model. In order to validate the model, a setup was constructed for testing on high-voltage winding of cast resin dry-type transformer. The simulation results were compared with the experimental data measured from FRA and impulse tests.
Calculation codes in radiation protection, radiation physics and dosimetry
2003-01-01
These scientific days had for objective to draw up the situation of calculation codes of radiation transport, of sources estimation, of radiation doses managements and to draw the future perspectives. (N.C.)
Dark energy and key physical parameters of clusters of galaxies
Bisnovatyi-Kogan, G. S.; Chernin, A. D.
2012-04-01
We study physics of clusters of galaxies embedded in the cosmic dark energy background. Under the assumption that dark energy is described by the cosmological constant, we show that the dynamical effects of dark energy are strong in clusters like the Virgo cluster. Specifically, the key physical parameters of the dark mater halos in clusters are determined by dark energy: (1) the halo cut-off radius is practically, if not exactly, equal to the zero-gravity radius at which the dark matter gravity is balanced by the dark energy antigravity; (2) the halo averaged density is equal to two densities of dark energy; (3) the halo edge (cut-off) density is the dark energy density with a numerical factor of the unity order slightly depending on the halo profile. The cluster gravitational potential well in which the particles of the dark halo (as well as galaxies and intracluster plasma) move is strongly affected by dark energy: the maximum of the potential is located at the zero-gravity radius of the cluster.
Semi-analytical calculation of fuel parameters for shock ignition fusion
S A Ghasemi
2017-02-01
Full Text Available In this paper, semi-analytical relations of total energy, fuel gain and hot-spot radius in a non-isobaric model have been derived and compared with Schmitt (2010 numerical calculations for shock ignition scenario. in nuclear fusion. Results indicate that the approximations used by Rosen (1983 and Schmitt (2010 for the calculation of burn up fraction have not enough accuracy compared with numerical simulation. Meanwhile, it is shown that the obtained formulas of non-isobaric model cannot determine the model parameters of total energy, fuel gain and hot-spot radius uniquely. Therefore, employing more appropriate approximations, an improved semianalytical relations for non-isobaric model has been presented, which are in a better agreement with numerical calculations of shock ignition by Schmitt (2010.
On the calculation of errors and choice of the parameters of radioisotope following level meters
Kalinin, O.V.; Matveev, V.S.; Khatskevich, M.V.
1979-01-01
A method for calculating errors of radioisotope following level meters is considered with account of nonlinearity of the system control units. The statistical method of analysis of linear control systems and the approximated method of statistical linearization of nonlinear systems are used during calculating error of a following level meter. Calculation of a nonlinear system by the method of statistical linearization comprises approximation of a nonlinear characteristic by linearized dependence on the base of a certain criterion. Dispersion calculations of output coordinate of a measuring converter are given for different cases of the system input signal. Dependences of fluctuation error on system parameters for level meters with proportional and relay control have been plotted on the base of the given methods. It is stated, that fluctuation error in both cases depend on time constant of a counting rate meter. Minimal error of the level meter decreases with the growth of operating counting rate and with the increase of nonsensitivity zone width. It is also noted, that parameters of the following level meter should be chosen according to requirements for measuring error, device reliability and time of reading fixing
Calculation and Identification of the Aerodynamic Parameters for Small-Scaled Fixed-Wing UAVs
Jieliang Shen
2018-01-01
Full Text Available The establishment of the Aircraft Dynamic Model (ADM constitutes the prerequisite for the design of the navigation and control system, but the aerodynamic parameters in the model could not be readily obtained especially for small-scaled fixed-wing UAVs. In this paper, the procedure of computing the aerodynamic parameters is developed. All the longitudinal and lateral aerodynamic derivatives are firstly calculated through semi-empirical method based on the aerodynamics, rather than the wind tunnel tests or fluid dynamics software analysis. Secondly, the residuals of each derivative are proposed to be identified or estimated further via Extended Kalman Filter(EKF, with the observations of the attitude and velocity from the airborne integrated navigation system. Meanwhile, the observability of the targeted parameters is analyzed and strengthened through multiple maneuvers. Based on a small-scaled fixed-wing aircraft driven by propeller, the airborne sensors are chosen and the model of the actuators are constructed. Then, real flight tests are implemented to verify the calculation and identification process. Test results tell the rationality of the semi-empirical method and show the improvement of accuracy of ADM after the compensation of the parameters.
Calculation and Identification of the Aerodynamic Parameters for Small-Scaled Fixed-Wing UAVs.
Shen, Jieliang; Su, Yan; Liang, Qing; Zhu, Xinhua
2018-01-13
The establishment of the Aircraft Dynamic Model(ADM) constitutes the prerequisite for the design of the navigation and control system, but the aerodynamic parameters in the model could not be readily obtained especially for small-scaled fixed-wing UAVs. In this paper, the procedure of computing the aerodynamic parameters is developed. All the longitudinal and lateral aerodynamic derivatives are firstly calculated through semi-empirical method based on the aerodynamics, rather than the wind tunnel tests or fluid dynamics software analysis. Secondly, the residuals of each derivative are proposed to be identified or estimated further via Extended Kalman Filter(EKF), with the observations of the attitude and velocity from the airborne integrated navigation system. Meanwhile, the observability of the targeted parameters is analyzed and strengthened through multiple maneuvers. Based on a small-scaled fixed-wing aircraft driven by propeller, the airborne sensors are chosen and the model of the actuators are constructed. Then, real flight tests are implemented to verify the calculation and identification process. Test results tell the rationality of the semi-empirical method and show the improvement of accuracy of ADM after the compensation of the parameters.
Harmonising Reference Intervals for Three Calculated Parameters used in Clinical Chemistry.
Hughes, David; Koerbin, Gus; Potter, Julia M; Glasgow, Nicholas; West, Nic; Abhayaratna, Walter P; Cavanaugh, Juleen; Armbruster, David; Hickman, Peter E
2016-08-01
For more than a decade there has been a global effort to harmonise all phases of the testing process, with particular emphasis on the most frequently utilised measurands. In addition, it is recognised that calculated parameters derived from these measurands should also be a target for harmonisation. Using data from the Aussie Normals study we report reference intervals for three calculated parameters: serum osmolality, serum anion gap and albumin-adjusted serum calcium. The Aussie Normals study was an a priori study that analysed samples from 1856 healthy volunteers. The nine analytes used for the calculations in this study were measured on Abbott Architect analysers. The data demonstrated normal (Gaussian) distributions for the albumin-adjusted serum calcium, the anion gap (using potassium in the calculation) and the calculated serum osmolality (using both the Bhagat et al. and Smithline and Gardner formulae). To assess the suitability of these reference intervals for use as harmonised reference intervals, we reviewed data from the Royal College of Pathologists of Australasia/Australasian Association of Clinical Biochemists (RCPA/AACB) bias survey. We conclude that the reference intervals for the calculated serum osmolality (using the Smithline and Gardner formulae) may be suitable for use as a common reference interval. Although a common reference interval for albumin-adjusted serum calcium may be possible, further investigations (including a greater range of albumin concentrations) are needed. This is due to the bias between the Bromocresol Green (BCG) and Bromocresol Purple (BCP) methods at lower serum albumin concentrations. Problems with the measurement of Total CO 2 in the bias survey meant that we could not use the data for assessing the suitability of a common reference interval for the anion gap. Further study is required.
A study on physics parameters and flux behaviour for a fast critical facility using ''Baker'' model
Abu-Leilah, M.M.; Hussein, A.Z.; Gaafar, M.A.; Hamouda, I.F.
1983-01-01
Comparative study was performed to emphasize the effects of using different nuclear data systems and methods on the various parameters of the fast reactor. Multigroup libraries as 11 (ANL-5800) and 26 (BNAB-64) energy group systems of nuclear data constants were used in the present work. The calculations were carried out for both infinite dilution (self-shielding factor F= 1) and self-shielded cross sections. Various computer codes were elaborated and derived to meet the conditional requirements for such calculations. The important output of these calculations are the neutron spectra, neutron balance, fission and capture rate distributions, critical mass, breeding ratio in each region and total breeding ratio of the reactor. Five different cases of study were considered employing two systems of constants, infinite dilution and self-shielded cross-sections and treating stainless steel of the reactor as to be substituted by iron. Moreover, calculations have been concerned for averaged one group nuclear data constants which were condensed from the 11 and 26 group systems. Comparisons of the multigroup results with those of the group were made. The condensation process for averaging to one group was done to estimate the effect of such physical simplification on the calculated parameters. The present work results have been compared with many published works. Fair agreements are obtained, which varified the consistance and completeness of the methods implemented and used
Physics calculations for the Clinch River Breeder Reactor
Kalimullah; Kier, P.H.; Hummel, H.H.
1977-06-01
Calculations of distributions of power and sodium void reactivity, unvoided and voided Doppler coefficients and steel and fuel worths have been performed using diffusion theory and first-order perturbation theory for the LWR discharge Pu-fueled CRBR at BOL, the FFTF-grade Pu-fueled CRBR at BOL and for the beginning and end of equilibrium cycle of the LWR-Pu-fueled CRBR. The results of the burnup and breeding ratio calculations performed for obtaining the reactor compositions during the equilibrium cycle are also reported. Effects of sodium and steel contents on the distributions of sodium void reactivity and steel worth have also been studied. Errors and uncertainties in the reactivity coefficients due to cross-sections and the two-dimensional geometric representations of the reactor used in the calculations have also been estimated. Comparisons of the results with those in the CRBR PSAR are also discussed
Preliminary physics calculations for the Clinch River Breeder Reactor
Kalimullah.
1975-01-01
Calculations of sodium void, fuel, and clad worths, power distribution, and control rod worths have been carried out for an R-Z model of the CRBR, using diffusion theory and first-order perturbation theory for material worths. The power distribution and control rod worths have also been calculated in two-dimensional triangular mesh geometry. The present results are preliminary because of inaccuracy of the reactor model and the cross sections used, but the final results are not expected to be greatly different. (U.S.)
Neutron physics calculation for WWER-1000 absorber element lifetime determination
Kurakin, K.Yu.; Kushmanov, S.A.
2009-01-01
Absorber element with compound absorber has been operating in WWER-1000 power units since 1995. AE design meets operating organizations requirements for reliability, service life (to 10 years) and safety functions. Extension of AE service life up to 20 - 30 years by the complex of calculation and experimental work is an important problem of WWER new designs development. The paper deals with the issues related to calculation determination of main factors that influence AE service life limitation - neutron flux and fluence onto absorbing and structural materials during extended service life. (Authors)
Lopes, Antonio Augusto; Miranda, Rogerio dos Anjos; Goncalves, Rilvani Cavalcante; Thomaz, Ana Maria
2009-01-01
In patients with congenital heart disease undergoing cardiac catheterization for hemodynamic purposes, parameter estimation by the indirect Fick method using a single predicted value of oxygen consumption has been a matter of criticism. We developed a computer-based routine for rapid estimation of replicate hemodynamic parameters using multiple predicted values of oxygen consumption. Using Microsoft Excel facilities, we constructed a matrix containing 5 models (equations) for prediction of oxygen consumption, and all additional formulas needed to obtain replicate estimates of hemodynamic parameters. By entering data from 65 patients with ventricular septal defects, aged 1 month to 8 years, it was possible to obtain multiple predictions for oxygen consumption, with clear between-age groups ( P <.001) and between-methods ( P <.001) differences. Using these predictions in the individual patient, it was possible to obtain the upper and lower limits of a likely range for any given parameter, which made estimation more realistic. The organized matrix allows for rapid obtainment of replicate parameter estimates, without error due to exhaustive calculations. (author)
Home Field Advantage Calculation for Physical Education and Sport Students
Inan, Tugbay
2018-01-01
It is a well-established fact that playing at home field is an advantageous condition for professional sport teams. For this reason, the home field advantage in team sports is an important issue to be explored. It is also one of the different topics that physical education and sports students can use when they want to perform performance analysis…
Influential parameters for designing and power consumption calculating of cumin mower
Mahmoodi, E.; Jafari, A. [Tehran Univ., Karaj (Iran, Islamic Republic of). Dept. of Agricultural Machinery Engineering
2010-07-01
This paper reported on a study in which the consuming power and design of cumin mowers was calculated. The parameters required for calculating power consumption and designing of cumin mowers were measured along with some engineering properties of cumin stems. These included shearing and bending tests on cumin stem and specifying the coefficient of friction between mower knives and cumin stem. The relationships between static and dynamic friction forces being exerted on mower runners by soil with normal load were determined along with the factor affecting soil moisture. Some of the other parameters that are important for calculating the power consumption and design of an optimized mower include harvest moisture content; maximum and average of cumin stem diameter; maximum bio-yield point of force and maximum ultimate point of force in the cutting; average energy required to cut a stem; maximum elasticity module; maximum bending rupture force; average energy required for bending a stem; friction coefficient between the stem and knife edge; relation between bio-yield force, failure force, elasticity and diameter in the cutting; relation between rupture forces and diameter in the bending; and mower weight.
Study of the methodology for sensitivity calculations of fast reactors integral parameters
Renke, C.A.C.
1981-06-01
A study of the methodology for sensitivity calculations of integral parameters of fast reactors for the adjustment of multigroup cross sections is presented. A description of several existent methods and theories is given, with special emphasis being regarded to variational perturbation theory, integrant of the sensitivity code VARI-1D used in this work. Two calculational systems are defined and a set of procedures and criteria is structured gathering the necessary conditions for the determination of the sensitivity coefficients. These coefficients are then computed by both the direct method and the variational perturbation theory. A reasonable number of sensitivity coefficients are computed and analyzed for three fast critical assemblies, covering a range of special interest of the spectrum. These coefficients are determined for severa integral parameters, for the capture and fission cross sections of the U-238 and Pu-239, covering all the energy up to 14.5 MeV. The nuclear data used were obtained the CARNAVAL II calculational system of the Instituto de Engenharia Nuclear. An optimization for sensitivity computations in a chainned sequence of procedures is made, yielding the sensitivities in the energy macrogroups as the final stage. (Author) [pt
Vignati, E.; Hertel, O.; Berkowicz, R. [National Environmental Research Inst., Dept. of Atmospheric Enviroment (Denmark); Raaschou-Nielsen, O. [Danish Cancer Society, Division of Cancer Epidemiology (Denmark)
1997-05-01
The method for generation of the input data for the calculations with OSPM is presented in this report. The described method which is based on information provided from a questionnaire, will be used for model calculations of long term exposure for a large number of children in connection with an epidemiological study. A test of the calculation method has been performed on a few locations in which detailed measurements of air pollution, meteorological data and traffic were available. Comparisons between measured and calculated concentrations were made for hourly, monthly and yearly values. Beside the measured concentrations, the test results were compared to results obtained with the optimal street configuration data and measured traffic. The main conclusions drawn from this investigation are: (1) The calculation method works satisfactory well for long term averages, whereas the uncertainties are high when short term averages are considered. (2) The street width is one of the most crucial input parameters for the calculation of street pollution levels for both short and long term averages. Using H.C. Andersens Boulevard as an example, it was shown that estimation of street width based on traffic amount can lead to large overestimation of the concentration levels (in this case 50% for NO{sub x} and 30% for NO{sub 2}). (3) The street orientation and geometry is important for prediction of short term concentrations but this importance diminished for longer term averages. (4) The uncertainties in diurnal traffic profiles can influence the accuracy of short term averages, but are less important for long term averages. The correlation is good between modelled and measured concentrations when the actual background concentrations are replaced with the generated values. Even though extreme situations are difficult to reproduce with this method, the comparison between the yearly averaged modelled and measured concentrations is very good. (LN) 20 refs.
Application Of WIMS Code To Calculation Kartini Reactor Parameters By Pin-Cell And Cluster Method
Sumarsono, Bambang; Tjiptono, T.W.
1996-01-01
Analysis UZrH fuel element parameters calculation in Kartini Reactor by WIMS Code has been done. The analysis is done by pin cell and cluster method. The pin cell method is done as a function percent burn-up and by 8 group 3 region analysis and cluster method by 8 group 12 region analysis. From analysis and calculation resulted K ∼ = 1.3687 by pin cell method and K ∼ = 1.3162 by cluster method and so deviation is 3.83%. By pin cell analysis as a function percent burn-up at the percent burn-up greater than 59.50%, the multiplication factor is less than one (k ∼ < 1) it is mean that the fuel element reactivity is negative
Ertl, P
1998-02-01
Easy to use, interactive, and platform-independent WWW-based tools are ideal for development of chemical applications. By using the newly emerging Web technologies such as Java applets and sophisticated scripting, it is possible to deliver powerful molecular processing capabilities directly to the desk of synthetic organic chemists. In Novartis Crop Protection in Basel, a Web-based molecular modelling system has been in use since 1995. In this article two new modules of this system are presented: a program for interactive calculation of important hydrophobic, electronic, and steric properties of organic substituents, and a module for substituent similarity searches enabling the identification of bioisosteric functional groups. Various possible applications of calculated substituent parameters are also discussed, including automatic design of molecules with the desired properties and creation of targeted virtual combinatorial libraries.
Reardon, P.T.; Mullen, M.F.
1982-08-01
As part of Task C.35 (Calculation of Parameters for Inspection Planning and Evaluation) of the US Program of Technical Assistance to IAEA Safeguards, Pacific Northwest Laboratory has performed some quantitative analyses of IAEA inspection activities for mixed-oxide fuel fabrication facilities. There were four distinct efforts involved in this task. These were as follows: show the effect on a material balance verification of using two variables measurement methods in some strata; perform additional calculations for the reference facility described in STR-89; modify the INSPECT computer programs to be used as an after-inspection analysis tool, as well as a preinspection planning tool; provide written comments and explantations of text and graphs of the first draft of STR-89, Safeguards Considerations for Mixed-Oxide Fuel Element Fabrication Facilities, by W. Bahm, T. Shea, and D. Tolchenkov, System Studies Section, IAEA
Reardon, P.T.; Mullen, M.F.; Harms, N.L.
1981-02-01
As part of Task C.35 (Calculation of Parameters for Inspection Planning and Evaluation) of the US Program of Technical Assistance to IAEA Safeguards, Pacific Northwest Laboratory has performed some quantitative analyses of IAEA inspection activities at low-enriched uranium (LEU) conversion and fuel fabrication facilities. This report presents the results and conclusions of those analyses. Implementation of IAEA safeguards at LEU conversion and fuel fabrication facilities must take into account a variety of practical problems and constraints. One of the key concerns is the problem of flow verification, especially product verification. The objective of this report is to help put the problem of flow verification in perspective by presenting the results of some specific calculations of inspection effort and probability of detection for various product measurement strategies. In order to provide quantitative information about the advantages and disadvantages of the various strategies, eight specific cases were examined
On the distortions in calculated GW parameters during slanted atmospheric soundings
de la Torre, Alejandro; Alexander, Peter; Schmidt, Torsten; Llamedo, Pablo; Hierro, Rodrigo
2018-03-01
The significant distortions introduced in the measured atmospheric gravity wavelengths by soundings other than those in vertical and horizontal directions, are discussed as a function of the elevation angle of the sounding path and the gravity wave aspect ratio. Under- or overestimation of real vertical wavelengths during the measurement process depends on the value of these two parameters. The consequences of these distortions on the calculation of the energy and the vertical flux of horizontal momentum are analyzed and discussed in the context of two experimental limb satellite setups: GPS-LEO radio occultations and TIMED/SABER ((Atmosphere using Broadband Emission Radiometry/Thermosphere-Ionosphere-Mesosphere-Energetics and Dynamics)) measurements. Possible discrepancies previously found between the momentum flux calculated from satellite temperature profiles, on site and from model simulations, may to a certain degree be attributed to these distortions. A recalculation of previous momentum flux climatologies based on these considerations seems to be a difficult goal.
Hamma, M; Miranda, R P; Vasilevskiy, M I; Zorkani, I
2007-01-01
An accurate calculation of the exciton-phonon interaction matrix elements and Huang-Rhys parameter for nearly spherical nanocrystals (NCs) of polar semiconductor materials is presented. The theoretical approach is based on a continuum lattice dynamics model and the effective mass approximation for electronic states in the NCs. A strong confinement regime is considered for both excitons and optical phonons, taking into account both the Froehlich-type and optical deformation potential (ODP) mechanisms of the exciton-phonon interaction. The effects of exchange electron-hole interaction and possible hexagonal crystal structure of the underlying material are also taken into account. The theory is applied to CdSe and InP quantum dots. It is shown that the ODP mechanism, almost unimportant for CdSe, dominates the exciton-phonon coupling in small InP dots. The effect of the non-diagonal interaction, not included in the Huang-Rhys parameter, is briefly discussed
Estimation of Adjoint-Weighted Kinetics Parameters in Monte Carlo Wieland Calculations
Choi, Sung Hoon; Shim, Hyung Jin
2013-01-01
The effective delayed neutron fraction, β eff , and the prompt neutron generation time, Λ, in the point kinetics equation are weighted by the adjoint flux to improve the accuracy of the reactivity estimate. Recently the Monte Carlo (MC) kinetics parameter estimation methods by using the self-consistent adjoint flux calculated in the MC forward simulations have been developed and successfully applied for the research reactor analyses. However these adjoint estimation methods based on the cycle-by-cycle genealogical table require a huge memory size to store the pedigree hierarchy. In this paper, we present a new adjoint estimation in which the pedigree of a single history is utilized by applying the MC Wielandt method. The effectiveness of the new method is demonstrated in the kinetics parameter estimations for infinite homogeneous two-group problems and the Godiva critical facility
Krutitskiy M.N.
2016-03-01
Full Text Available The method of statistical tests examines the impact of the correlation of the parameters of fatigue-such as the durability of the shaft mechanism of an overhead traveling crane for General use is under consideration in this article. It is be-lieved that the normal and shear stresses together affect the overall durability of the shaft. There may be a correlation between endurance limits and coefficients of block similarity of loading. To calculate resource used corrected linear theory of fatigue damage accumulation. Parameters on the reliability are computed after building the function, the reli-ability function directly or through private functions the reliability function for each type of stress.
Plessis, S.; McDougall, D.; Mandt, K.; Greathouse, T.; Luspay-Kuti, A.
2015-11-01
Bimolecular diffusion coefficients are important parameters used by atmospheric models to calculate altitude profiles of minor constituents in an atmosphere. Unfortunately, laboratory measurements of these coefficients were never conducted at temperature conditions relevant to the atmosphere of Titan. Here we conduct a detailed uncertainty analysis of the bimolecular diffusion coefficient parameters as applied to Titan's upper atmosphere to provide a better understanding of the impact of uncertainty for this parameter on models. Because temperature and pressure conditions are much lower than the laboratory conditions in which bimolecular diffusion parameters were measured, we apply a Bayesian framework, a problem-agnostic framework, to determine parameter estimates and associated uncertainties. We solve the Bayesian calibration problem using the open-source QUESO library which also performs a propagation of uncertainties in the calibrated parameters to temperature and pressure conditions observed in Titan's upper atmosphere. Our results show that, after propagating uncertainty through the Massman model, the uncertainty in molecular diffusion is highly correlated to temperature and we observe no noticeable correlation with pressure. We propagate the calibrated molecular diffusion estimate and associated uncertainty to obtain an estimate with uncertainty due to bimolecular diffusion for the methane molar fraction as a function of altitude. Results show that the uncertainty in methane abundance due to molecular diffusion is in general small compared to eddy diffusion and the chemical kinetics description. However, methane abundance is most sensitive to uncertainty in molecular diffusion above 1200 km where the errors are nontrivial and could have important implications for scientific research based on diffusion models in this altitude range.
Calculation of neutronic parameters of IEA-R1 reactor and purpose of a new configuration
Kosaka, N.; Fanaro, L.C.C.B.; Yamaguchi, M.
1989-01-01
The program for reducing the fuel enrichment of the IEA-R1 reactor considers fuel plates containing U308-AL with 19,9% of U-235. The geometry of the new 18 fuel plate fuel elements has been kept the same. This work describes the calculation methods utilized at IPEN-CNEN/SP and some neutronic parameters of the present configuration of IEA-R1 as well as for a new configuration porposed with a new LEU fuel element are shown. (author) [pt
Oliveira, L.E.M.C. de.
1976-01-01
The electronic structure of the interstitial hydrogen atom in alkaline-earth fluorides has been studied using the self-consistent-field multiple-scattering Xα method. In the calculations a cluster constituted by the hydrogen atom and its first anion and cation neighbors has been used. The contact parameters with the proton and the fluorine nuclei have been evaluated. The agreement obtained with the experimental results is in general good and indicates that this method is also appropriate to study defects in ionic crystals. (author) [pt
EPR parameters of E centers inν-SiO2 from first-principles calculations
Giacomazzi, Luigi; Martin-Samos, L.; Boukenter, A.; Ouerdane, Y.; Girard, S.; Richard, N.
2014-01-01
A first-principles investigation of E' centers in vitreous silica (ν-SiO 2 ) based on calculations of the electron paramagnetic resonance (EPR) parameters is presented. The EPR parameters are obtained by exploiting the gauge including projector augmented wave method as implemented in the QUANTUM-ESPRESSO package. First, we analyze the EPR parameters of a large number of Si 2 dimers. The g tensor of the Si 2 dimers is shown to possess an average rhombic symmetry and larger g principal values with respect to those observed, e.g., for the E 'γ center in silica. Furthermore, the g principal values clearly show a linear trend with the Si-Si dimer length. Our results suggest that the Si 2 dimers could correspond to an unidentified paramagnetic center, though occasionally the calculated g principal values of the Si 2 dimer might be compatible with those found experimentally for the E' δ center. Next, we generate non dimer configurations by a procedure involving structural relaxations in the subsequent positively charged states. In particular, puckered, un-puckered, doubly puckered, and forward-oriented configurations are generated. The distributions of the calculated EPR parameters of the puckered and un-puckered configurations further support the assignment of the E' γ center to an unpaired spin localized at a threefold coordinated silicon dangling bond. Moreover, by analyzing Fermi contacts and g tensors of the puckered and forward-oriented configurations, we suggest the assignment of the E' α center to the latter type of configurations. This work also suggests that the differences in the EPR parameters of E' α and E' γ centers mainly arise from the strained geometry of the silicon dangling bond. In the forward-oriented configurations, one Si-O bond is about 0.2 Angstroms longer than the remaining two, whereas in the silicon dangling bond of the puckered and un-puckered configurations, all three bonds have a length of ≅1
Poludniowski, Gavin G. [Joint Department of Physics, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, United Kingdom and Centre for Vision Speech and Signal Processing (CVSSP), Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Evans, Philip M. [Centre for Vision Speech and Signal Processing (CVSSP), Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)
2013-04-15
Purpose: Monte Carlo methods based on the Boltzmann transport equation (BTE) have previously been used to model light transport in powdered-phosphor scintillator screens. Physically motivated guesses or, alternatively, the complexities of Mie theory have been used by some authors to provide the necessary inputs of transport parameters. The purpose of Part II of this work is to: (i) validate predictions of modulation transform function (MTF) using the BTE and calculated values of transport parameters, against experimental data published for two Gd{sub 2}O{sub 2}S:Tb screens; (ii) investigate the impact of size-distribution and emission spectrum on Mie predictions of transport parameters; (iii) suggest simpler and novel geometrical optics-based models for these parameters and compare to the predictions of Mie theory. A computer code package called phsphr is made available that allows the MTF predictions for the screens modeled to be reproduced and novel screens to be simulated. Methods: The transport parameters of interest are the scattering efficiency (Q{sub sct}), absorption efficiency (Q{sub abs}), and the scatter anisotropy (g). Calculations of these parameters are made using the analytic method of Mie theory, for spherical grains of radii 0.1-5.0 {mu}m. The sensitivity of the transport parameters to emission wavelength is investigated using an emission spectrum representative of that of Gd{sub 2}O{sub 2}S:Tb. The impact of a grain-size distribution in the screen on the parameters is investigated using a Gaussian size-distribution ({sigma}= 1%, 5%, or 10% of mean radius). Two simple and novel alternative models to Mie theory are suggested: a geometrical optics and diffraction model (GODM) and an extension of this (GODM+). Comparisons to measured MTF are made for two commercial screens: Lanex Fast Back and Lanex Fast Front (Eastman Kodak Company, Inc.). Results: The Mie theory predictions of transport parameters were shown to be highly sensitive to both grain size
Craig, D.S.; Festarini, G.L.
1986-07-01
The Monte Carlo code, REPC, has been used to calculate resonance reaction rates for the thermal test lattices TRX-1 and MIT-4, and for the CRNL lattices ZEEP-1, 19 UO 2 and 37 UO 2 . These reaction rates were used in the RAHAB cell code to calculate k eff , conversion ratios, and fast fission ratios, for comparison with experimental values. The calculations used the cluster geometry for the 19-, 28-, and 37-element clusters. Calculations were also made using annular representations of the cluster for comparison of the rates with those obtained using the discrete ordinate code OZMA
Can we calculate the fundamental dimensionless constants of physics
Barut, A.O.
1987-07-01
We review some dynamical models to calculate the dimensionless constants α=e 2 /4πε 0 (h/2π)c, β=M p /m e (or β'=m μ /m e ), γ=G Fermi m e 2 /c(h/2π) 3 and δ=G Newton m e 2 /(e 2 /4πε 0 ) which are associated with the four different manifestations (electromagnetic, strong, weak and gravitational) of a possible single interaction. (author). 15 refs
New approach to invariant-embedding methods in reactor physics calculations
Forsbacka, M.J.; Rydin, R.A.
1997-01-01
Invariant-embedding methods offer an alternative approach to modeling physical phenomena and solving mathematical problems. Invariant embedding allows one to express traditional boundary-value problems as initial-value problems. In doing this, one effectively reformulates a problem to be solved in terms of an embedding parameter. In this paper, a hybrid method that consists of Monte Carlo-generated response functions that describe the neutronic properties of local spatial cells are coupled together in a global reactor model using the invariant embedding methodology, where the system multiplication factor k eff is used as the embedding parameter. Thus, k eff is computed directly rather than as the result of a secondary eigenvalue calculation. Because the response functions can represent any arbitrary material distribution within a local cell, this method shows promise to accurately assess the change in reactivity due to core disruptive accidents and other changes in system configuration such as changing control rod positions. This paper reports a series of proof-of-concept calculations that assess this method
Seven health physics calculator programs for the HP-41CV
Rittmann, P.D.
1984-08-01
Several user-oriented programs for the Hewlett-Packard HP-41CV are explained. The first program builds, stores, alters, and ages a list of radionuclides. This program only handles single- and double-decay chains. The second program performs convenient conversions for the six nuclides of concern in plutonium handling. The conversions are between mass, activity, and weight percents of the isotopes. The source can be aged and/or neutron generation rates can be computed. The third program is a timekeeping program that improves the process of manually estimating and tracking personnel exposure during high dose rate tasks by replacing the pencil, paper, and stopwatch method. This program requires a time module. The remaining four programs deal with computations of time-integrated air concentrations at various distances from an airborne release. Building wake effects, source depletion by ground deposition, and sector averaging can all be included in the final printout of the X/Q - Hanford and X/Q - Pasquill programs. The shorter versions of these, H/Q and P/Q, compute centerline or sector-averaged values and include a subroutine to facilitate dose estimation by entering dose factors and quantities released. The horizontal and vertical dispersion parameters in the Pasquill-Gifford programs were modeled with simple, two-parameter functions that agreed very well with the usual textbook graphs. 8 references, 7 appendices
Gaussian optics calculations of the parameters of a magnetic sector energy analyzer
Zaluzec, N.J.
1978-01-01
The design of a magnetic deflection system for use as an electron energy loss spectrometer can be a complex process if one takes the most general approach. However, for application to materials research the design process can be reduced to three basic steps. First, the qualitative features of the overall system are defined--i.e., incident electron energy, required resolution, type of magnet, the desired focal properties, etc. Secondly, the design parameters necessary to meet these requirements are calculated using the appropriate equations. Finally, once the magnetic field has been specified, ray-tracing techniques can be employed to verify the system response to the conditions defined in the first two steps. The calculation of the parameters of a uniform field magnetic sector analyzer capable of energy resolutions of 20 ppM or better are considered. Higher resolution is attainable; however, for most materials work, more important considerations are the attainment of double focusing to improve S/N, the minimization of aberrations and the achievement of a flat image plane to facilitate parallel data recording
Parameters for HL-LHC aperture calculations and comparison with aperture measurements
Bruce, R; Fartoukh, S; Giovannozzi, M; Redaelli, S; Tomas, R; Wenninger, J
2014-01-01
When β∗ is squeezed to smaller values in the LHC, the beam size in the inner triplet increases so that the aperture risks to be exposed to unwanted beam losses. A 2D calculation model was used during the design stage to study the aperture margins, both there and at other potential bottlenecks. Based on assumptions on orbit and optics errors, as well as mechanical tolerances, it gives the available aperture in units of the RMS beam size, which can be compared with what can be protected by the collimation system. During the LHC Run I in 2010-2013, several of the error tolerances have been found smaller than the design assumptions. Furthermore, the aperture has been measured with beam several times and the results are compatible with a very well aligned machine, with results close to the design values. In this report, we therefore review the assumptions in the model and propose an updated set of input parameters to be used for aperture calculations at top energy in HL-LHC. The new parameter set is based on th...
Reis, A.; Lopes, R.; Lourenco, M.; Cardoso, J.
2006-01-01
The Human Respiratory Tract Model proposed by the ICRP Publication 66 accounts for the morphology and physiology of the respiratory tract. The ICRP 66 presents deposition fraction in the respiratory tract regions considering reference values from Caucasian man. However, in order to obtain a more accurate assessment of intake and dose the ICRP recommends the use of specific information when they are available. The application of parameters from Brazilian population in the deposition and in the clearance model shows significant variations in the deposition fractions and in the fraction of inhaled activity transferred to blood. The main objective of this study is to evaluate the influence in dose calculation to each region of the respiratory tract when physiological parameters from Brazilian population are applied in the model. The purpose of the dosimetric model is to evaluate dose to each tissues of respiratory tract that are potentially risk from inhaled radioactive materials. The committed equivalent dose, H.T., is calculated by the product of the total number of transformations of the radionuclide in tissue source S over a period of fifty years after incorporation and of the energy absorbed per unit mass in the target tissue T, for each radiation emitted per transformation in tissue source S. The dosimetric model of Human Respirator y Tract was implemented in the software Excel for Windows (version 2000) and H.T. was determined in two stages. First it was calculated the number of total transformations, US, considering the fractional deposition of activity in each source tissue and then it was calculated the total energy absorbed per unit mass S.E.E., in the target tissue. It was assumed that the radionuclide emits an alpha particle with average energy of 5.15 MeV. The variation in the fractional deposition in the compartments of the respiratory tract in changing the physiological parameters from Caucasian to Brazilian adult man causes variation in the number of
Monte Carlo sampling on technical parameters in criticality and burn-up-calculations
Kirsch, M.; Hannstein, V.; Kilger, R.
2011-01-01
The increase in computing power over the recent years allows for the introduction of Monte Carlo sampling techniques for sensitivity and uncertainty analyses in criticality safety and burn-up calculations. With these techniques it is possible to assess the influence of a variation of the input parameters within their measured or estimated uncertainties on the final value of a calculation. The probabilistic result of a statistical analysis can thus complement the traditional method of figuring out both the nominal (best estimate) and the bounding case of the neutron multiplication factor (k eff ) in criticality safety analyses, e.g. by calculating the uncertainty of k eff or tolerance limits. Furthermore, the sampling method provides a possibility to derive sensitivity information, i.e. it allows figuring out which of the uncertain input parameters contribute the most to the uncertainty of the system. The application of Monte Carlo sampling methods has become a common practice in both industry and research institutes. Within this approach, two main paths are currently under investigation: the variation of nuclear data used in a calculation and the variation of technical parameters such as manufacturing tolerances. This contribution concentrates on the latter case. The newly developed SUnCISTT (Sensitivities and Uncertainties in Criticality Inventory and Source Term Tool) is introduced. It defines an interface to the well established GRS tool for sensitivity and uncertainty analyses SUSA, that provides the necessary statistical methods for sampling based analyses. The interfaced codes are programs that are used to simulate aspects of the nuclear fuel cycle, such as the criticality safety analysis sequence CSAS5 of the SCALE code system, developed by Oak Ridge National Laboratories, or the GRS burn-up system OREST. In the following, first the implementation of the SUnCISTT will be presented, then, results of its application in an exemplary evaluation of the neutron
Chemical and physical parameters of dried salted pork meat
Petronela Cviková
2016-07-01
Full Text Available The aim of the present study was analysed and evaluated chemical and physical parameters of dried salted pork neck and ham. Dried salted meat is one of the main meat products typically produced with a variety of flavors and textures. Neck (14 samples and ham (14 samples was salted by nitrite salt mixture during 1week. The nitrite salt mixture for salting process (dry salting was used. This salt mixture contains: salt, dextrose, maltodextrin, flavourings, stabilizer E316, taste enhancer E621, nitrite mixture. The meat samples were dried at 4 °C and relative humudity 85% after 1 week salting. The weight of each sample was approximately 1 kg. After salting were vacuum-packed and analysed after 1 week. The traditional dry-cured meat such as dry-cured ham and neck obtained after 12 - 24 months of ripening under controlled conditions. The average protein content was significantly (p <0.001 lower in dried pork neck in comparison with dried salted pork ham. The average intramuscular fat was significantly (p <0.001 lower in dried pork ham in comparison with dried salted pork neck. The average moisture was significantly lower (p ≤0.05 in dried salted ham in comparison with dried pork neck. The average pH value was 5.50 in dried salted pork ham and 5.75 in dried salted pork neck. The content of arginine, phenylalanine, isoleucine, leucine and threonine in dried salted ham was significantly lower (p <0.001 in comparison with dried salted pork neck. The proportion of analysed amino acids from total proteins was 56.31% in pork salted dried ham and 56.50% in pork salted dried neck. Normal 0 21 false false false EN-GB X-NONE X-NONE Normal 0 21 false false false SK X-NONE X-NONE
Dynamic simulation of flash drums using rigorous physical property calculations
F. M. Gonçalves
2007-06-01
Full Text Available The dynamics of flash drums is simulated using a formulation adequate for phase modeling with equations of state (EOS. The energy and mass balances are written as differential equations for the internal energy and the number of moles of each species. The algebraic equations of the model, solved at each time step, are those of a flash with specified internal energy, volume and mole numbers (UVN flash. A new aspect of our dynamic simulations is the use of direct iterations in phase volumes (instead of pressure for solving the algebraic equations. It was also found that an iterative procedure previously suggested in the literature for UVN flashes becomes unreliable close to phase boundaries and a new alternative is proposed. Another unusual aspect of this work is that the model expressions, including the physical properties and their analytical derivatives, were quickly implemented using computer algebra.
Identification of Physical Parameters for A Hydraulic Robot
Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik
1997-01-01
This paper describes a case study of identifying the physical model of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application of the laws of physics...
FORTRAN Code for Glandular Dose Calculation in Mammography Using Sobol-Wu Parameters
Mowlavi A A
2007-07-01
Full Text Available Background: Accurate computation of the radiation dose to the breast is essential to mammography. Various the thicknesses of breast, the composition of the breast tissue and other variables affect the optimal breast dose. Furthermore, the glandular fraction, which refers to the composition of the breasts, as partitioned between radiation-sensitive glandular tissue and the adipose tissue, also has an effect on this calculation. Fatty or fibrous breasts would have a lower value for the glandular fraction than dense breasts. Breast tissue composed of half glandular and half adipose tissue would have a glandular fraction in between that of fatty and dense breasts. Therefore, the use of a computational code for average glandular dose calculation in mammography is a more effective means of estimating the dose of radiation, and is accurate and fast. Methods: In the present work, the Sobol-Wu beam quality parameters are used to write a FORTRAN code for glandular dose calculation in molybdenum anode-molybdenum filter (Mo-Mo, molybdenum anode-rhodium filter (Mo-Rh and rhodium anode-rhodium filter (Rh-Rh target-filter combinations in mammograms. The input parameters of code are: tube voltage in kV, half-value layer (HVL of the incident x-ray spectrum in mm, breast thickness in cm (d, and glandular tissue fraction (g. Results: The average glandular dose (AGD variation against the voltage of the mammogram X-ray tube for d = 4 cm, HVL = 0.34 mm Al and g=0.5 for the three filter-target combinations, as well as its variation against the glandular fraction of breast tissue for kV=25, HVL=0.34, and d=4 cm has been calculated. The results related to the average glandular absorbed dose variation against HVL for kV = 28, d=4 cm and g= 0.6 are also presented. The results of this code are in good agreement with those previously reported in the literature. Conclusion: The code developed in this study calculates the glandular dose quickly, and it is complete and
METHODOLOGY FOR HYDRAULIC CALCULATION OF RIVER REGULATION AND DETERMINATION OF DIKE PARAMETERS
E. I. Mikhnevich
2017-01-01
Full Text Available Territory protection against flood water inundation and creation of polder systems are carried out with the help of protection dikes. One of the main requirements to the composition of polder systems in flood plains is a location of border dikes beyond meander belt in order to avoid their erosion when meander development occurs. Meander belt width can be determined on the basis of the analysis of multi-year land surveying pertaining top river-bed building and in the case when such data is not available this parameter is calculated in accordance with the Snishchenko formula. While banking-up a river bed a flooded area is decreasing and, consequently, water level in inter-dike space and rate of flood water are significantly increasing. For this reason it is necessary to locate dikes at a such distance from a river bed which will not cause rather high increase in water level and flow velocity in the inter-dike space. Methodology for hydraulic calculation of river regulation has been developed in order to substantiate design parameters for levee systems, creation of favourable hydraulic regime in these systems and provision of sustainability for dikes. Its main elements are calculations of pass-through capacity of the leveed channel and rise of water level in inter-dike space, and distance between dikes and their crest level. Peculiar feature of the proposed calculated formulae is an interaction consideration of channel and inundated flows. Their mass-exchanging process results in slowing-down of the channel flow and acceleration of the inundated flow. This occurrence is taken into account and coefficients of kinematic efficiency are introduced to the elements of water flow rate in the river channel and flood plain, respectively. The adduced dependencies for determination of a dike crest level (consequently their height take into consideration a rise of water level in inter-dike space for two types of polder systems: non-inundable (winter dikes with
Casoli, P.; Authier, N.; Baud, J. [Commissariat a l' energie Atomique, Centre de Valduc, 21120 Is-sur-Tille (France)
2009-07-01
Several experimental devices are operated by the Criticality and Neutron Science Research Department of the CEA Valduc Laboratory. One of these is the metallic core reactor Caliban. The knowledge of the fundamental kinetic parameters of the reactor is very useful, indeed necessary, to the operator. The purpose of this study was to develop and perform experiments allowing to determinate some of these parameters. The prompt neutron decay constant and particularly its value at criticality can be measured with reactor noise techniques such as the interval-distribution, the Feynman variance-to-mean, and the Rossi-{alpha} methods. By introducing the Nelson number, the effective delayed neutron fraction and the average neutron lifetime can also be calculated with the Rossi-{alpha} method. Subcritical, critical, and even supercritical experiments were performed. With the Rossi-{alpha} technique, it was found that the prompt neutron decay constant at criticality was (6.02*10{sup 5} {+-} 9%). Experiments also brought out the limitations of the used experimental parameters. (authors)
Development of a reference scheme for MOX lattice physics calculations
Finck, P.J.; Stenberg, C.G.; Roy, R.
1998-01-01
The US program to dispose of weapons-grade Pu could involve the irradiation of mixed-oxide (MOX) fuel assemblies in commercial light water reactors. This will require licensing acceptance because of the modifications to the core safety characteristics. In particular, core neutronics will be significantly modified, thus making it necessary to validate the standard suites of neutronics codes for that particular application. Validation criteria are still unclear, but it seems reasonable to expect that the same level of accuracy will be expected for MOX as that which has been achieved for UO 2 . Commercial lattice physics codes are invariably claimed to be accurate for MOX analysis but often lack independent confirmation of their performance on a representative experimental database. Argonne National Laboratory (ANL) has started implementing a public domain suite of codes to provide for a capability to perform independent assessments of MOX core analyses. The DRAGON lattice code was chosen, and fine group ENDF/B-VI.04 and JEF-2.2 libraries have been developed. The objective of this work is to validate the DRAGON algorithms with respect to continuous-energy Monte Carlo for a suite of realistic UO 2 -MOX benchmark cases, with the aim of establishing a reference DRAGON scheme with a demonstrated high level of accuracy and no computing resource constraints. Using this scheme as a reference, future work will be devoted to obtaining simpler and less costly schemes that preserve accuracy as much as possible
Ben Mosbah, Abdallah
In order to improve the qualities of wind tunnel tests, and the tools used to perform aerodynamic tests on aircraft wings in the wind tunnel, new methodologies were developed and tested on rigid and flexible wings models. A flexible wing concept is consists in replacing a portion (lower and/or upper) of the skin with another flexible portion whose shape can be changed using an actuation system installed inside of the wing. The main purpose of this concept is to improve the aerodynamic performance of the aircraft, and especially to reduce the fuel consumption of the airplane. Numerical and experimental analyses were conducted to develop and test the methodologies proposed in this thesis. To control the flow inside the test sections of the Price-Paidoussis wind tunnel of LARCASE, numerical and experimental analyses were performed. Computational fluid dynamics calculations have been made in order to obtain a database used to develop a new hybrid methodology for wind tunnel calibration. This approach allows controlling the flow in the test section of the Price-Paidoussis wind tunnel. For the fast determination of aerodynamic parameters, new hybrid methodologies were proposed. These methodologies were used to control flight parameters by the calculation of the drag, lift and pitching moment coefficients and by the calculation of the pressure distribution around an airfoil. These aerodynamic coefficients were calculated from the known airflow conditions such as angles of attack, the mach and the Reynolds numbers. In order to modify the shape of the wing skin, electric actuators were installed inside the wing to get the desired shape. These deformations provide optimal profiles according to different flight conditions in order to reduce the fuel consumption. A controller based on neural networks was implemented to obtain desired displacement actuators. A metaheuristic algorithm was used in hybridization with neural networks, and support vector machine approaches and their
Monte Carlo simulation of core physics parameters of the Nigeria Research Reactor-1 (NIRR-1)
Jonah, S.A. [Reactor Engineering Section, Centre for Energy Research and Training, Ahmadu Bello University, Zaria, P.M.B. 1014 (Nigeria)], E-mail: jonahsa2001@yahoo.com; Liaw, J.R.; Matos, J.E. [RERTR Program, Nuclear Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)
2007-12-15
The Monte Carlo N-Particle (MCNP) code, version 4C (MCNP4C) and a set of neutron cross-section data were used to develop an accurate three-dimensional computational model of the Nigeria Research Reactor-1 (NIRR-1). The geometry of the reactor core was modeled as closely as possible including the details of all the fuel elements, reactivity regulators, the control rod, all irradiation channels, and Be reflectors. The following reactor core physics parameters were calculated for the present highly enriched uranium (HEU) core: clean cold core excess reactivity ({rho}{sub ex}), control rod (CR) and shim worth, shut down margin (SDM), neutron flux distributions in the irradiation channels, reactivity feedback coefficients and the kinetics parameters. The HEU input model was validated by experimental data from the final safety analyses report (SAR). The model predicted various key neutronics parameters fairly accurately and the calculated thermal neutron fluxes in the irradiation channels agree with the values obtained by foil activation method. Results indicate that the established Monte Carlo model is an accurate representation of the NIRR-1 HEU core and will be used to perform feasibility for conversion to low enriched uranium (LEU)
Adelmann, S; Schembecker, G
2011-08-12
Besides the selection of a suitable biphasic solvent system the separation efficiency in Centrifugal Partition Chromatography (CPC) is mainly influenced by the hydrodynamics in the chambers. The flow pattern, the stationary phase retention and the interfacial area for mass transfer strongly depend on physical properties of the solvent system and operating parameters. In order to measure these parameters we visualized the hydrodynamics in a FCPC-chamber for five different solvent systems with an optical measurement system and calculated the stationary phase retention, interfacial area and the distribution of mobile phase thickness in the chamber. Although inclined chambers were used we found that the Coriolis force always deflected the mobile phase towards the chamber wall reducing the interfacial area. This effect increased for systems with low density difference. We also have shown that the stability of phase systems (stationary phase retention) and its tendency to disperse increased for smaller values of the ratio of interfacial tension and density difference. But also the viscosity ratio and the flow pattern itself had a significant effect on retention and dispersion of the mobile phase. As a result operating parameters should be chosen carefully with respect to physical properties for a CPC system. In order to reduce the effect of the Coriolis force CPC devices with greater rotor radius are desirable. Copyright © 2011 Elsevier B.V. All rights reserved.
He Jie; Zhang Binbin
2013-01-01
In the probabilistic safety assessment (PSA) of nuclear power plants, there are few historical records on some initiating event frequencies or component failures in industry. In order to determine the noninformative priors of such reliability parameters and initiating event frequencies, the Jeffreys method in Bayesian statistics was employed. The mathematical mechanism of the Jeffreys prior and the simplified constrained noninformative distribution (SCNID) were elaborated in this paper. The Jeffreys noninformative formulas and the credible intervals of the Gamma-Poisson and Beta-Binomial models were introduced. As an example, the small break loss-of-coolant accident (SLOCA) was employed to show the application of the Jeffreys prior in determining an initiating event frequency. The result shows that the Jeffreys method is an effective method for noninformative prior calculation. (authors)
Barrera Figueroa, Salvador; Rasmussen, Knud; Jacobsen, Finn
2009-01-01
to this problem is to measure the velocity distribution of the membrane by means of a non-contact method, such as laser vibrometry. The measured velocity distribution can be used together with a numerical formulation such as the boundary element method for estimating the microphone response and other parameters......, e.g., the acoustic center. In this work, such a hybrid method is presented and examined. The velocity distributions of a number of condenser microphones have been determined using a laser vibrometer, and these measured velocity distributions have been used for estimating microphone responses......Typically, numerical calculations of the pressure, free-field, and random-incidence response of a condenser microphone are carried out on the basis of an assumed displacement distribution of the diaphragm of the microphone; the conventional assumption is that the displacement follows a Bessel...
Calculation of parameters of technological equipment for deep-sea mining
Yungmeister, D. A.; Ivanov, S. E.; Isaev, A. I.
2018-03-01
The actual problem of extracting minerals from the bottom of the world ocean is considered. On the ocean floor, three types of minerals are of interest: iron-manganese concretions (IMC), cobalt-manganese crusts (CMC) and sulphides. The analysis of known designs of machines and complexes for the extraction of IMC is performed. These machines are based on the principle of excavating the bottom surface; however such methods do not always correspond to “gentle” methods of mining. The ecological purity of such mining methods does not meet the necessary requirements. Such machines require the transmission of high electric power through the water column, which in some cases is a significant challenge. The authors analyzed the options of transportation of the extracted mineral from the bottom. The paper describes the design of machines that collect IMC by the method of vacuum suction. In this method, the gripping plates or drums are provided with cavities in which a vacuum is created and individual IMC are attracted to the devices by a pressure drop. The work of such machines can be called “gentle” processing technology of the bottom areas. Their environmental impact is significantly lower than mechanical devices that carry out the raking of IMC. The parameters of the device for lifting the IMC collected on the bottom are calculated. With the use of Kevlar ropes of serial production up to 0.06 meters in diameter, with a cycle time of up to 2 hours and a lifting speed of up to 3 meters per second, a productivity of about 400,000 tons per year can be realized for IMC. The development of machines based on the calculated parameters and approbation of their designs will create a unique complex for the extraction of minerals at oceanic deposits.
Mueller, R.G.
1987-06-01
Due to the strong influence of vapour bubbles on the nuclear chain reaction, an exact calculation of neutron physics and thermal hydraulics in light water reactors requires consideration of subcooled boiling. To this purpose, in the present study a dynamic model is derived from the time-dependent conservation equations. It contains new methods for the time-dependent determination of evaporation and condensation heat flow and for the heat transfer coefficient in subcooled boiling. Furthermore, it enables the complete two-phase flow region to be treated in a consistent manner. The calculation model was verified using measured data of experiments covering a wide range of thermodynamic boundary conditions. In all cases very good agreement was reached. The results from the coupling of the new calculation model with a neutron kinetics program proved its suitability for the steady-state and transient calculation of reactor cores. (orig.) [de
Leisure-time physical activity and some psychological parameters ...
... physical work capacity for the demands of daily living and job performance. ... physical activity and psychological well-being of executive employees; and to ... A cross-sectional study design was carried out on a group of 156 (mean age; ...
The High Level Mathematical Models in Calculating Aircraft Gas Turbine Engine Parameters
Yu. A. Ezrokhi
2017-01-01
Full Text Available The article describes high-level mathematical models developed to solve special problems arising at later stages of design with regard to calculation of the aircraft gas turbine engine (GTE under real operating conditions. The use of blade row mathematics models, as well as mathematical models of a higher level, including 2D and 3D description of the working process in the engine units and components, makes it possible to determine parameters and characteristics of the aircraft engine under conditions significantly different from the calculated ones.The paper considers application of mathematical modelling methods (MMM for solving a wide range of practical problems, such as forcing the engine by injection of water into the flowing part, estimate of the thermal instability effect on the GTE characteristics, simulation of engine start-up and windmill starting condition, etc. It shows that the MMM use, when optimizing the laws of the compressor stator control, as well as supplying cooling air to the hot turbine components in the motor system, can significantly improve the integral traction and economic characteristics of the engine in terms of its gas-dynamic stability, reliability and resource.It ought to bear in mind that blade row mathematical models of the engine are designed to solve purely "motor" problems and do not replace the existing models of various complexity levels used in calculation and design of compressors and turbines, because in “quality” a description of the working processes in these units is inevitably inferior to such specialized models.It is shown that the choice of the mathematical modelling level of an aircraft engine for solving a particular problem arising in its designing and computational study is to a large extent a compromise problem. Despite the significantly higher "resolution" and information ability the motor mathematical models containing 2D and 3D approaches to the calculation of flow in blade machine
Monte Carlo code Serpent calculation of the parameters of the stationary nuclear fission wave
V. M. Khotyayintsev
2017-12-01
Full Text Available n this work, propagation of the stationary nuclear fission wave was simulated for series of fixed power values using Monte Carlo code Serpent. The wave moved in the axial direction in 5 m long cylindrical core of fast reactor with pure 238U raw fuel. Stationary wave mode arises some period later after the wave ignition and lasts sufficiently long to determine kef with high enough accuracy. The velocity characteristic of the reactor was determined as the dependence of the wave velocity on the neutron multiplication factor. As we have recently shown within a one-group diffusion description, the velocity characteristic is two-valued due to the effect of concentration mechanisms, while thermal feedback affects it only quantitatively. The shape and parameters of the velocity characteristic critically affect feasibility of the reactor design since stationary wave solutions of the lower branch are unstable and do not correspond to any real waves in self-regulated reactor, like CANDLE. In this work calculations were performed without taking into account thermal feedback. They confirm that theoretical dependence correctly describes the shape of the velocity characteristic calculated using the results of the Serpent modeling.
Scholten, O.; Trinh, T. N. G.; de Vries, K. D.; Hare, B. M.
2018-01-01
The radio intensity and polarization footprint of a cosmic-ray induced extensive air shower is determined by the time-dependent structure of the current distribution residing in the plasma cloud at the shower front. In turn, the time dependence of the integrated charge-current distribution in the plasma cloud, the longitudinal shower structure, is determined by interesting physics which one would like to extract, such as the location and multiplicity of the primary cosmic-ray collision or the values of electric fields in the atmosphere during thunderstorms. To extract the structure of a shower from its footprint requires solving a complicated inverse problem. For this purpose we have developed a code that semianalytically calculates the radio footprint of an extensive air shower given an arbitrary longitudinal structure. This code can be used in an optimization procedure to extract the optimal longitudinal shower structure given a radio footprint. On the basis of air-shower universality we propose a simple parametrization of the structure of the plasma cloud. This parametrization is based on the results of Monte Carlo shower simulations. Deriving the parametrization also teaches which aspects of the plasma cloud are important for understanding the features seen in the radio-emission footprint. The calculated radio footprints are compared with microscopic CoREAS simulations.
Calculation of parameters of the original state of material radiation damage
Krasnoshtanov, V.F.; Kevorkyan, Yu.R.; Eremin, Yu.P.; Belousov, G.G.
1974-01-01
The program ''Sample'' for evaluating the parameters of the initial state of radiation damage in samples irradiated by neutrons of different energies is described in this paper. Within the framework of this study, a program is elaborated for calculating the spectrum and density of initially knocked-on atoms in cylinder and parallelepiped-shaped samples, as well as in plates of various thickness. The model incorporated into the program is based on the Monte-Carlo method. In considering the neutron-to-atom interaction account is taken of the elastic scattering anisotropy and the process of inelastic scattering. This program is used to study the radiation damage states in iron samples irradiated by neutrons of different energies. A computer handled this program is based on sequential sampling of random values with a predetermined distribution law. The algorithm of the neutron's walk through a medium forms the basis of the ''Sample'' program. This program permits calculating, for a particular sample geometry, the initially knocked-on atom density and spectrum, as well as the density of the displacements due to the monoenergetic neutrons isotropically incident on the sample surface. The program also enables calculation of the static computation error. The block diagram of the ''Sample'' program and its text written in FORTRAN are presented. Also given is the dependence of the displacement density normalized with respect to the unit flux on the neutron energy for a parallelepiped-shaped sample. The neutron flux is determined by the number of collisions. The contribution of various energetic groups of initially knocked-on atoms into the radiation damage of a sample depending on the neutron energy is shown
Filipović Ivan
2011-01-01
Full Text Available The main role in air/fuel mixture formation at the IC diesel engines has the energy introduced by fuel into the IC engine that is the characteristics of spraying fuel into the combustion chamber. The characteristic can be defined by the spray length, the spray cone angle, the physical and the chemical structure of fuel spray by different sections. Having in mind very complex experimental setups for researching in this field, the mentioned characteristics are mostly analyzed by calculations. There are two methods in the literature, the first based on use of the semi-empirical expressions (correlations and the second, the calculations of spray characteristics by use of very complex mathematical methods. The second method is dominant in the modern literature. The main disadvantage of the calculation methods is a correct definition of real state at the end of the nozzle orifice (real boundary conditions. The majority of the researchers in this field use most frequently the coefficient of total losses inside the injector. This coefficient depends on injector design, as well as depends on the level of fuel energy and fuel energy transformation along the injector. Having in mind the importance of the real boundary conditions, the complex methods for calculation of the fuel spray characteristics should have the calculation of fuel flows inside the injector and the calculation of spray characteristics together. This approach is a very complex numerical problem and there are no existing computer programs with satisfactory calculation results. Analysis of spray characteristics by use of the semi-empirical expressions (correlations is presented in this paper. The special attention is dedicated to the analysis of the constant in the semi-empirical expressions and influence parameters on this constant. Also, the method for definition of realistic boundary condition at the end of the nozzle orifice is presented in the paper. By use of this method completely
Koning, A.
2008-01-01
Full text: Masses: Adopted Goriely HFB masses in TALYS as theoretical default instead of Moeller. Audi-Wapstra, Moeller and HFB masses tested formally with TALYS. Levels. Adopted latest discrete level update (2006) by Belgya (as sent by Capote) in TALYS. Tested with TALYS. Resonances. Adopted RIPL-2 D0 collection in TALYS. Tested by TALYS. Optical model. Coordinated Optical model segment for RIPL-3. Adopted Soukhovitskii CC potential as default for actinides. Covariances: Confirmed OMP parameter uncertainties from last meeting. Level density. Produced consistent set of level density parameters for CTM, BFM, GSM and HFM. Local models (per nucleus) and global models (systematics). With and without effective collective enhancement. Included and tested with TALYS Gamma-ray strength. Adopted Goriely HFB strength function tables as option (not default) in TALYS. Both formally tested and validated with TALYS. Fission. Adopted Sin-Capote WKB approximation in TALYS as option for fission calculations. Formally tested. RIPL-2/3 validation. Very extensive formal tests and validation procedures with TALYS. MONKEY code for random input files (has found RIPL errors in the past). Automatic comparison with all available EXFOR cross section data (for level density study). Started work on global parameter uncertainties (for covariances). SALTY nuclear data library (final version under construction): - 60 MeV n,g,p,d,t,h,a activation files for 1200 nuclides - 200 MeV n,g,p,d,t,h,a transport files for 250 nuclides RIPL is automatically being used by all TALYS users (and TALYS-related publications). TALYS-1.0 release in December 2007 (delay because of level densities). (author)
Jiang, Chao; Qiao, Mingzhong; Zhu, Peng
2017-12-01
A permanent magnet synchronous motor with radial magnetic circuit and built-in permanent magnet is designed for the electric vehicle. Finite element numerical calculation and experimental measurement are adopted to obtain the direct axis and quadrature axis inductance parameters of the motor which are vital important for the motor control. The calculation method is simple, the measuring principle is clear, the results of numerical calculation and experimental measurement are mutual confirmation. A quick and effective method is provided to obtain the direct axis and quadrature axis inductance parameters of the motor, and then improve the design of motor or adjust the control parameters of the motor controller.
Sadeghi, Mahdi; Hosseini, Hamed; Raisali, Gholamreza
2008-01-01
Full text: The use of 103 Pd seed sources for permanent prostate implantation has become a popular brachytherapy application. As recommended by AAPM the dosimetric characteristics of the new source must be determined using experimental and Monte Carlo simulations, before its use in clinical applications thus The goal of this report is the experimental and theoretical determination of the dosimetric characteristics of this source following the recommendations in the AAPM TG-43U1 protocol. Figure 1 shows the geometry of the IRA- 103 Pd source. The source consists of a cylindrical silver core, 0.3 cm long x 0.05 cm in diameter, onto which 0.5 nm layer of 103 Pd has been uniformly adsorbed. The effective active length of source is 0.3 cm and the silver core encapsulated inside a hollow titanium tube with 0.45 cm long, 0.07 cm and 0.08 inner and outer diameters and two caps. The Monte Carlo N-Particle (MCNP) code, version 4C, was used to determine the relevant dosimetric parameters of the source. The geometry of the Monte Carlo simulation performed in this study consisted of a sphere with 30 cm diameter. Dose distributions around this source were measured in two Perspex phantom using enough TLD chips. For these measurements, slabs of Perspex material were machined to accommodate the source and TLD chips. A value of 0.67± 1% cGy.h -1 .U -1 for, Λ, was calculated as the ratio of d(r 0 ,θ 0 ) and s K , that may be compared with Λ values obtained for 103 Pd sources. Result of calculations and measurements values of dosimetric parameters of the source including radial dose function, g(r), and anisotropy function, F(r,θ), has been shown in separate figures. The radial dose function, g(r), for the IRA- 103 Pd source and other 103 Pd sources is included in Fig. 2. Comparison between measured and Monte Carlo simulated dose function, g(r), and anisotropy function, F(r,θ), of this source demonstrated that they are in good agreement with each other and The value of Λ is
SITE-94. Chemical and physical transport parameters for SITE-94
Andersson, Karin [Chalmers Univ. of Technology, Goeteborg (Sweden). Technical Environmental Planning
1996-02-01
Important parameters are the interactions of radionuclides with solid surfaces, parameters describing the geometrical conditions like porosity, data on water composition (ionic strength, pH, redox conditions, complex formers etc) and data on the solids that may be of importance to the water and radionuclide chemistry. In this report some of these data of relevance for the Aespoe site are discussed. Based on a literature survey, sorption data as well as values for some other parameters have been selected for rock, fracture fillings and bentonite relevant to the chemical conditions in and around a repository at Aespoe. A comparison to data used for earlier, site-specific as well as general, safety assessments of underground repositories has been performed. The data are recommendations for modelling of radionuclide release from a hypothetical high level waste repository at Aespoe. Since the data to a large extent are not based on experimental measurements, more accurate predictions may be expected if more experimental data are available. Before such studies are performed for a specific site, a variational analysis in order to evaluate the importance of the single parameters is recommended. After such a study, the key parameters may be investigated in detail and the modelling can be expected to be more accurate what concerns influence of single parameters. However, the uncertainty in conceptual areas like how to model accurately the long term hydrology of the site etc still remains. 32 refs.
Guseva, E.V.; Peregudov, V.N.
1982-01-01
The FITGAV program for calculation of parameters of the Gauss curve describing experimental data is considered. The calculations are based on the least square fit method. The estimations of errors in the parameter determination as a function of experimental data sample volume and their statistical significance are obtained. The curve fit using 100 points occupies less than 1 s at the SM-4 type computer
Laureau, Axel
2015-01-01
In this PhD thesis, we describe the development of innovative neutronic models for their coupling with thermal hydraulics such that they combine precision and reasonable computational times. One of the main cases where this method is applied is the Molten Salt Fast Reactor (MSFR) whose combines a fast neutron spectrum with a thorium cycle. In this fourth generation reactor, the motion of the delayed neutron precursors and the associated phenomena have to be taken into account due to the liquid fuel circulation. The starting point for these developments was the preliminary design of this type of system where a dedicated multi-physical representation was needed to study the reactor performance in steady and transient conditions. As a first step, a stationary coupling was developed. A neutronic model based on a stochastic approach was associated to a CFD (Computational Fluid Dynamics) code to solve the Navier Stokes equations for turbulent flows and the transport of the delayed neutron precursors. The impact of this precursor motion is taken into account by reconstructing the prompt shower that they generate. This approach, called by shower, views the critical reactor as a prompt subcritical reactor that amplifies a source of delayed neutrons. A second step consisted in developing a neutronic model based on a time dependent version of the fission matrices (Transient Fission Matrix or TFM) so as to enable reactor transient studies. With the TFM model, an initial computation of the matrices with a stochastic code (MCNP, SERPENT) allows the characterization of the global spatial and time dependent neutronic response of the reactor with a precision close to that of a Monte Carlo calculation. The information thus obtained is then used to calculate transients, while retaining the advantage of reduced computational time. The TFM model, which can be used for various system concepts, also allows the evaluation of effective kinetic parameters such as the effective fraction of
Weibull Parameters Estimation Based on Physics of Failure Model
Kostandyan, Erik; Sørensen, John Dalsgaard
2012-01-01
Reliability estimation procedures are discussed for the example of fatigue development in solder joints using a physics of failure model. The accumulated damage is estimated based on a physics of failure model, the Rainflow counting algorithm and the Miner’s rule. A threshold model is used...... for degradation modeling and failure criteria determination. The time dependent accumulated damage is assumed linearly proportional to the time dependent degradation level. It is observed that the deterministic accumulated damage at the level of unity closely estimates the characteristic fatigue life of Weibull...
Element-specific and constant parameters used for dose calculations in SR-Site
Norden, Sara; Avila, Rodolfo; De la Cruz, Idalmis; Stenberg, Kristofer; Grolander, Sara
2010-12-01
The report presents Best Estimate (BE) values and Probability Distribution Functions (PDFs) of Concentration Ratios (CR) for different types of terrestrial and aquatic biota and distribution coefficients (K d ) for organic and inorganic deposits, as well as for suspended matter in freshwater and marine ecosystems. The BE values have been used in deterministic simulations for derivation of Landscape Dose Factors (LDF) applied for dose assessments in SR-Site. The PDFs have been used in probabilistic simulations for uncertainty and sensitivity analysis of the LDFs. The derivation of LDFs for SR-Site is described in /Avila et al. 2010/. The CR and K d values have been derived using both site-specific data measured at Laxemar and Forsmark during the site investigation program and literature data. These two data sources have been combined using Bayesian updating methods, which are described in detail in an Appendix, along with the input data used in the statistical analyses and the results obtained. The report also describes a kinetic-allometric model that was applied for deriving values of CR for terrestrial herbivores in cases when site and literature data for an element were missing. In addition, the report presents values for a number of other parameters used in the SR-Site Radionuclide Model for the biosphere: radionuclide decay-ingrowth data, elemental diffusivities, fractions of element content released during decomposition processes, ingestion of food, water and soil by cattle, elements retention fraction on plant surfaces during irrigation. The report also presents parameter values used in calculation of doses to a reference man: dose coefficients for inhalation, ingestion and external exposure, inhalation rates, ingestion rates of food and water
Element-specific and constant parameters used for dose calculations in SR-Site
Norden, Sara (Svensk Kaernbraenslehantering AB (Sweden)); Avila, Rodolfo; De la Cruz, Idalmis; Stenberg, Kristofer; Grolander, Sara (Facilia AB (Sweden))
2010-12-15
The report presents Best Estimate (BE) values and Probability Distribution Functions (PDFs) of Concentration Ratios (CR) for different types of terrestrial and aquatic biota and distribution coefficients (K{sub d}) for organic and inorganic deposits, as well as for suspended matter in freshwater and marine ecosystems. The BE values have been used in deterministic simulations for derivation of Landscape Dose Factors (LDF) applied for dose assessments in SR-Site. The PDFs have been used in probabilistic simulations for uncertainty and sensitivity analysis of the LDFs. The derivation of LDFs for SR-Site is described in /Avila et al. 2010/. The CR and K{sub d} values have been derived using both site-specific data measured at Laxemar and Forsmark during the site investigation program and literature data. These two data sources have been combined using Bayesian updating methods, which are described in detail in an Appendix, along with the input data used in the statistical analyses and the results obtained. The report also describes a kinetic-allometric model that was applied for deriving values of CR for terrestrial herbivores in cases when site and literature data for an element were missing. In addition, the report presents values for a number of other parameters used in the SR-Site Radionuclide Model for the biosphere: radionuclide decay-ingrowth data, elemental diffusivities, fractions of element content released during decomposition processes, ingestion of food, water and soil by cattle, elements retention fraction on plant surfaces during irrigation. The report also presents parameter values used in calculation of doses to a reference man: dose coefficients for inhalation, ingestion and external exposure, inhalation rates, ingestion rates of food and water
Fast, Ivan; Aksyutina, Yuliya; Tietze-Jaensch, Holger [Product Quality Control Office for Radioactive Waste (PKS) at the Institute of Energy and Climate Research, Nuclear Waste Management and Reactor Safety Research, IEK-6, Forschungszentrum Juelich (Germany)
2013-07-01
Burn up calculations facilitate a determination of the composition and nuclear inventory of spent nuclear fuel, if operational history is known. In case this information is not available, the total nuclear inventory can be determined by means of destructive or, even on industrial scale, nondestructive measurement methods. For non-destructive measurements however only a few easy-to-measure, so-called key nuclides, are determined due to their characteristic gamma lines or neutron emission. From these measured activities the fuel burn up and cooling time are derived to facilitate the numerical inventory determination of spent fuel elements. Most regulatory bodies require an independent assessment of nuclear waste properties and their documentation. Prominent part of this assessment is a consistency check of inventory declaration. The waste packages often contain wastes from different types of spent fuels of different history and information about the secondary reactor parameters may not be available. In this case the so-called characteristic fuel burn up and cooling time are determined. These values are obtained from a correlations involving key-nuclides with a certain bandwidth, thus with upper and lower limits. The bandwidth is strongly dependent on secondary reactor parameter such as initial enrichment, temperature and density of the fuel and moderator, hence the reactor type, fuel element geometry and plant operation history. The purpose of our investigation is to look into the scaling and correlation limitations, to define and verify the range of validity and to scrutinize the dependencies and propagation of uncertainties that affect the waste inventory declarations and their independent verification. This is accomplished by numerical assessment and simulation of waste production using well accepted codes SCALE 6.0 and 6.1 to simulate the cooling time and burn up of a spent fuel element. The simulations are benchmarked against spent fuel from the real reactor
On different types of adjustment usable to calculate the parameters of the stream power law
Demoulin, Alain; Beckers, Arnaud; Bovy, Benoît
2012-02-01
Model parameterization through adjustment to field data is a crucial step in the modeling and the understanding of the drainage network response to tectonic or climatic perturbations. Using as a test case a data set of 18 knickpoints that materialize the migration of a 0.7-Ma-old erosion wave in the Ourthe catchment of northern Ardennes (western Europe), we explore the impact of various data fitting on the calibration of the stream power model of river incision, from which a simple knickpoint celerity equation is derived. Our results show that statistical least squares adjustments (or misfit functions) based either on the stream-wise distances between observed and modeled knickpoint positions at time t or on differences between observed and modeled time at the actual knickpoint locations yield significantly different values for the m and K parameters of the model. As there is no physical reason to prefer one of these approaches, an intermediate least-rectangles adjustment might at first glance appear as the best compromise. However, the statistics of the analysis of 200 sets of synthetic knickpoints generated in the Ourthe catchment indicate that the time-based adjustment is the most capable of getting close to the true parameter values. Moreover, this fitting method leads in all cases to an m value lower than that obtained from the classical distance adjustment (for example, 0.75 against 0.86 for the real case of the Ourthe catchment), corresponding to an increase in the non-linear character of the dependence of knickpoint celerity on discharge.
Physical characteristics and resistance parameters of typical urban cyclists.
Tengattini, Simone; Bigazzi, Alexander York
2018-03-30
This study investigates the rolling and drag resistance parameters and bicycle and cargo masses of typical urban cyclists. These factors are important for modelling of cyclist speed, power and energy expenditure, with applications including exercise performance, health and safety assessments and transportation network analysis. However, representative values for diverse urban travellers have not been established. Resistance parameters were measured utilizing a field coast-down test for 557 intercepted cyclists in Vancouver, Canada. Masses were also measured, along with other bicycle attributes such as tire pressure and size. The average (standard deviation) of coefficient of rolling resistance, effective frontal area, bicycle plus cargo mass, and bicycle-only mass were 0.0077 (0.0036), 0.559 (0.170) m 2 , 18.3 (4.1) kg, and 13.7 (3.3) kg, respectively. The range of measured values is wider and higher than suggested in existing literature, which focusses on sport cyclists. Significant correlations are identified between resistance parameters and rider and bicycle attributes, indicating higher resistance parameters for less sport-oriented cyclists. The findings of this study are important for appropriately characterising the full range of urban cyclists, including commuters and casual riders.
Valentine, T.E.; Mihalczo, J.T.
1995-01-01
This paper describes calculations performed to validate the modified version of the MCNP code, the MCNP-DSP, used for: the neutron and photon spectra of the spontaneous fission of californium 252; the representation of the detection processes for scattering detectors; the timing of the detection process; and the calculation of the frequency analysis parameters for the MCNP-DSP code
Calculations of physical and chemical reactions with DNA in aqueous solution from Auger cascades
Wright, H.A.; Hamm, R.N.; Turner, J.E.; Howell, R.W.; Rao, D.V.; Sastry, K.S.R.
1989-01-01
Monte Carlo calculations are performed of the physical and chemical interactions in liquid water by electrons produced during Auger cascades resulting from the decay of various radionuclides. Estimates are also made of the number of direct physical and indirect chemical interactions that would be produced on DNA located near the decay site. 13 refs., 8 figs
Makarycheva, A. I.; Faerman, V. A.
2017-02-01
The analyses of automation patterns is performed and the programming solution for the automation of data processing of the chromatographic data and their further information storage with a help of a software package, Mathcad and MS Excel spreadsheets, is developed. The offered approach concedes the ability of data processing algorithm modification and does not require any programming experts participation. The approach provides making a measurement of the given time and retention volumes, specific retention volumes, a measurement of differential molar free adsorption energy, and a measurement of partial molar solution enthalpies and isosteric heats of adsorption. The developed solution is focused on the appliance in a small research group and is tested on the series of some new gas chromatography sorbents. More than 20 analytes were submitted to calculation of retention parameters and thermodynamic sorption quantities. The received data are provided in the form accessible to comparative analysis, and they are able to find sorbing agents with the most profitable properties to solve some concrete analytic issues.
Investigating dynamic parameters in HWZPR ased on the experimental and calculated results
Nasrazadani, Zahra; Behfamia, Manochehar; Khosandi, Jamshid; Mirvakili, Mohammad [Reactors Research School, Nuclear Science And Technology Research Institute, Atomic Energy Organization of Iran, Esfahan (Iran, Islamic Republic of)
2016-10-15
The neutron decay constant, α, and effective delayed neutron fraction, β{sub eff}, are important parameters for the control of the dynamic behavior of nuclear reactors. For the heavy water zero power reactor (HWZPR), this document describes the measurements of the neutron decay constant by noise analysis methods, including variance to mean (VTM) ratio and endogenous pulse source (EPS) methods. The measured α is successively used to determine the experimental value of the effective delayed neutron fraction as well. According to the experimental results, β{sub eff} of the HWZPR reactor under study is equal to 7.84e-3. This value is finally used to validate the calculation of the effective delayed neutron fraction by the Monte Carlo methods that are discussed in the document. Using the Monte Carlo N-Particle (MCNP)-4C code, a β{sub eff} value of 7.58e-3 was obtained for the reactor under study. Thus, the relative difference between the β{sub eff} values determined experimentally and by Monte Carlo methods was estimated to be < 4%.
Advances in reactor physics education: Visualization of reactor parameters
Snoj, L.; Kromar, M.; Zerovnik, G.
2012-01-01
Modern computer codes allow detailed neutron transport calculations. In combination with advanced 3D visualization software capable of treating large amounts of data in real time they form a powerful tool that can be used as a convenient modern educational tool for reactor operators, nuclear engineers, students and specialists involved in reactor operation and design. Visualization is applicable not only in education and training, but also as a tool for fuel management, core analysis and irradiation planning. The paper treats the visualization of neutron transport in different moderators, neutron flux and power distributions in two nuclear reactors (TRIGA type research reactor and a typical PWR). The distributions are calculated with MCNP and CORD-2 computer codes and presented using Amira software. (authors)
Capote Noy, R.
2004-08-01
A summary is given of the First Research Coordination Meeting on Parameters for Calculation of Nuclear Reactions of Relevance to Non-Energy Nuclear Applications (Reference Input Parameter Library: Phase III), including a critical review of the RIPL-2 file. The new library should serve as input for theoretical calculations of nuclear reaction data at incident energies up to 200 MeV, as needed for energy and non-energy modern applications of nuclear data. Technical discussions and the resulting work plan of the Coordinated Research Programme are summarized, along with actions and deadlines. Participants' contributions to the RCM are also attached. (author)
Calculation of DSSC parameters based on ZnO nanorod/TiO2 mesoporous photoanode
Safriani, L.; Nurrida, A.; Mulyana, C.; Susilawati, T.; Bahtiar, A.; Aprilia, A.
2017-07-01
Photoanode of dye sensitized solar cell (DSSC) plays an important role as electron transport media to accept photogenerated electron from excited state of dye. There are several physical properties that are required from photoanode of DSSC. It should be highly transparent, have large surface area, has a conduction band lower than LUMO of dye molecule, has high charge carrier mobility and finally has a good stability in redox electrolyte process. In this work, DSSC with structure FTO/ZnO nanorod/TiO2 mesoporous/Ru-dye/gel electrolyte/ Pt/FTO has been fabricated. In order to modified the structures of photoanode, ZnO nanorod was grown on aluminium doped ZnO seed layer by variation concentration of Al (0 wt%, 0.5 wt% and 1.0 wt%). Zinc nitrate hexahydrate and hexamethylenetetramine used as raw materials for ZnO nanorod growth solution and deposited by self-assembly methods on FTO/Al doped ZnO seed layer. It is then followed by deposition of titania (TiO2) paste by screen printing methods. DSSC parameters i.e. ideally factor (n), series resistance (RS ), and shunt resistance (RSH ) was derived from current density-voltage (I-V) curve using the simplify equation of ideal diode model. The influences of ZnO photoanode structures to the solar cell performance will be completely discussed.
Core physics design calculation of mini-type fast reactor based on Monte Carlo method
He Keyu; Han Weishi
2007-01-01
An accurate physics calculation model has been set up for the mini-type sodium-cooled fast reactor (MFR) based on MCNP-4C code, then a detailed calculation of its critical physics characteristics, neutron flux distribution, power distribution and reactivity control has been carried out. The results indicate that the basic physics characteristics of MFR can satisfy the requirement and objectives of the core design. The power density and neutron flux distribution are symmetrical and reasonable. The control system is able to make a reliable reactivity balance efficiently and meets the request for long-playing operation. (authors)
Estimation of anisotropy parameters in organic-rich shale: Rock physics forward modeling approach
Herawati, Ida, E-mail: ida.herawati@students.itb.ac.id; Winardhi, Sonny; Priyono, Awali [Mining and Petroleum Engineering Faculty, Institut Teknologi Bandung, Bandung, 40132 (Indonesia)
2015-09-30
Anisotropy analysis becomes an important step in processing and interpretation of seismic data. One of the most important things in anisotropy analysis is anisotropy parameter estimation which can be estimated using well data, core data or seismic data. In seismic data, anisotropy parameter calculation is generally based on velocity moveout analysis. However, the accuracy depends on data quality, available offset, and velocity moveout picking. Anisotropy estimation using seismic data is needed to obtain wide coverage of particular layer anisotropy. In anisotropic reservoir, analysis of anisotropy parameters also helps us to better understand the reservoir characteristics. Anisotropy parameters, especially ε, are related to rock property and lithology determination. Current research aims to estimate anisotropy parameter from seismic data and integrate well data with case study in potential shale gas reservoir. Due to complexity in organic-rich shale reservoir, extensive study from different disciplines is needed to understand the reservoir. Shale itself has intrinsic anisotropy caused by lamination of their formed minerals. In order to link rock physic with seismic response, it is necessary to build forward modeling in organic-rich shale. This paper focuses on studying relationship between reservoir properties such as clay content, porosity and total organic content with anisotropy. Organic content which defines prospectivity of shale gas can be considered as solid background or solid inclusion or both. From the forward modeling result, it is shown that organic matter presence increases anisotropy in shale. The relationships between total organic content and other seismic properties such as acoustic impedance and Vp/Vs are also presented.
Estimation of anisotropy parameters in organic-rich shale: Rock physics forward modeling approach
Herawati, Ida; Winardhi, Sonny; Priyono, Awali
2015-01-01
Anisotropy analysis becomes an important step in processing and interpretation of seismic data. One of the most important things in anisotropy analysis is anisotropy parameter estimation which can be estimated using well data, core data or seismic data. In seismic data, anisotropy parameter calculation is generally based on velocity moveout analysis. However, the accuracy depends on data quality, available offset, and velocity moveout picking. Anisotropy estimation using seismic data is needed to obtain wide coverage of particular layer anisotropy. In anisotropic reservoir, analysis of anisotropy parameters also helps us to better understand the reservoir characteristics. Anisotropy parameters, especially ε, are related to rock property and lithology determination. Current research aims to estimate anisotropy parameter from seismic data and integrate well data with case study in potential shale gas reservoir. Due to complexity in organic-rich shale reservoir, extensive study from different disciplines is needed to understand the reservoir. Shale itself has intrinsic anisotropy caused by lamination of their formed minerals. In order to link rock physic with seismic response, it is necessary to build forward modeling in organic-rich shale. This paper focuses on studying relationship between reservoir properties such as clay content, porosity and total organic content with anisotropy. Organic content which defines prospectivity of shale gas can be considered as solid background or solid inclusion or both. From the forward modeling result, it is shown that organic matter presence increases anisotropy in shale. The relationships between total organic content and other seismic properties such as acoustic impedance and Vp/Vs are also presented
Elsa Tavernier
Full Text Available We aimed to examine the extent to which inaccurate assumptions for nuisance parameters used to calculate sample size can affect the power of a randomized controlled trial (RCT. In a simulation study, we separately considered an RCT with continuous, dichotomous or time-to-event outcomes, with associated nuisance parameters of standard deviation, success rate in the control group and survival rate in the control group at some time point, respectively. For each type of outcome, we calculated a required sample size N for a hypothesized treatment effect, an assumed nuisance parameter and a nominal power of 80%. We then assumed a nuisance parameter associated with a relative error at the design stage. For each type of outcome, we randomly drew 10,000 relative errors of the associated nuisance parameter (from empirical distributions derived from a previously published review. Then, retro-fitting the sample size formula, we derived, for the pre-calculated sample size N, the real power of the RCT, taking into account the relative error for the nuisance parameter. In total, 23%, 0% and 18% of RCTs with continuous, binary and time-to-event outcomes, respectively, were underpowered (i.e., the real power was 90%. Even with proper calculation of sample size, a substantial number of trials are underpowered or overpowered because of imprecise knowledge of nuisance parameters. Such findings raise questions about how sample size for RCTs should be determined.
Fiber coupled diode laser beam parameter product calculation and rules for optimized design
Wang, Zuolan; Segref, Armin; Koenning, Tobias; Pandey, Rajiv
2011-03-01
The Beam Parameter Product (BPP) of a passive, lossless system is a constant and cannot be improved upon but the beams may be reshaped for enhanced coupling performance. The function of the optical designer of fiber coupled diode lasers is to preserve the brightness of the diode sources while maximizing the coupling efficiency. In coupling diode laser power into fiber output, the symmetrical geometry of the fiber core makes it highly desirable to have symmetrical BPPs at the fiber input surface, but this is not always practical. It is therefore desirable to be able to know the 'diagonal' (fiber) BPP, using the BPPs of the fast and slow axes, before detailed design and simulation processes. A commonly used expression for this purpose, i.e. the square root of the sum of the squares of the BPPs in the fast and slow axes, has been found to consistently under-predict the fiber BPP (i.e. better beam quality is predicted than is actually achievable in practice). In this paper, using a simplified model, we provide the proof of the proper calculation of the diagonal (i.e. the fiber) BPP using BPPs of the fast and slow axes as input. Using the same simplified model, we also offer the proof that the fiber BPP can be shown to have a minimum (optimal) value for given diode BPPs and this optimized condition can be obtained before any detailed design and simulation are carried out. Measured and simulated data confirms satisfactory correlation between the BPPs of the diode and the predicted fiber BPP.
Dietrich, Johannes W.; Landgrafe-Mende, Gabi; Wiora, Evelin; Chatzitomaris, Apostolos; Klein, Harald H.; Midgley, John E. M.; Hoermann, Rudolf
2016-01-01
Although technical problems of thyroid testing have largely been resolved by modern assay technology, biological variation remains a challenge. This applies to subclinical thyroid disease, non-thyroidal illness syndrome, and those 10% of hypothyroid patients, who report impaired quality of life, despite normal thyrotropin (TSH) concentrations under levothyroxine (L-T4) replacement. Among multiple explanations for this condition, inadequate treatment dosage and monotherapy with L-T4 in subjects with impaired deiodination have received major attention. Translation to clinical practice is difficult, however, since univariate reference ranges for TSH and thyroid hormones fail to deliver robust decision algorithms for therapeutic interventions in patients with more subtle thyroid dysfunctions. Advances in mathematical and simulative modeling of pituitary–thyroid feedback control have improved our understanding of physiological mechanisms governing the homeostatic behavior. From multiple cybernetic models developed since 1956, four examples have also been translated to applications in medical decision-making and clinical trials. Structure parameters representing fundamental properties of the processing structure include the calculated secretory capacity of the thyroid gland (SPINA-GT), sum activity of peripheral deiodinases (SPINA-GD) and Jostel’s TSH index for assessment of thyrotropic pituitary function, supplemented by a recently published algorithm for reconstructing the personal set point of thyroid homeostasis. In addition, a family of integrated models (University of California-Los Angeles platform) provides advanced methods for bioequivalence studies. This perspective article delivers an overview of current clinical research on the basis of mathematical thyroid models. In addition to a summary of large clinical trials, it provides previously unpublished results of validation studies based on simulation and clinical samples. PMID:27375554
Bahreyni Toossi, M.T.; Hashemi, S.M.; Momen Nezhad, M.
2008-01-01
In recent decades, cancer has been one of the main ever increasing causes of death in developed countries. In order to fulfill the aforementioned considerations different techniques have been used, one of which is Monte Carlo simulation technique. High accuracy of the Monte Carlo simulation has been one of the main reason for its wide spread application. In this study, MCNP-4C code was employed to simulate electron mode of the Neptun 10 PC Linac, dosimetric quantities for conventional fields have also been both measured and calculated. Although Neptun 10 PC Linac is no longer licensed for installation in European and some other countries but regrettably nearly 10 of them have been installed in different centers around the country and are in operation. Therefore, in this circumstance, to improve the accuracy of treatment planning, Monte Carlo simulation for Neptun 10 PC was recognized as a necessity. Simulated and measured values of depth dose curves, off axis dose distributions for 6 , 8 and 10 MeV electrons applied for four different size fields, 6 x 6 cm 2 , 10 x 10 cm 2 , 15 x 15 cm 2 and 20 x 20 cm 2 were obtained. The measurements were carried out by a Welhofer-Scanditronix dose scanning system, Semiconductor Detector and Ionization Chamber. The results of this study have revealed that the values of two main dosimetric quantities depth dose curves and off axis dose distributions, acquired by MCNP-4C simulation and the corresponding values achieved by direct measurements are in a very good agreement (within 1% to 2% difference). In general, very good consistency of simulated and measured results, is a good proof that the goal of this work has been accomplished. In other word where measurements of some parameters are not practically achievable, MCNP-4C simulation can be implemented confidently. (author)
Mohajer, Ardavan; Tremier, Anne; Barrington, Suzelle; Teglia, Cecile
2010-01-01
Composting is a feasible biological treatment for the recycling of wastewater sludge as a soil amendment. The process can be optimized by selecting an initial compost recipe with physical properties that enhance microbial activity. The present study measured the microbial O(2) uptake rate (OUR) in 16 sludge and wood residue mixtures to estimate the kinetics parameters of maximum growth rate mu(m) and rate of organic matter hydrolysis K(h), as well as the initial biodegradable organic matter fractions present. The starting mixtures consisted of a wide range of moisture content (MC), waste to bulking agent (BA) ratio (W/BA ratio) and BA particle size, which were placed in a laboratory respirometry apparatus to measure their OUR over 4 weeks. A microbial model based on the activated sludge process was used to calculate the kinetic parameters and was found to adequately reproduced OUR curves over time, except for the lag phase and peak OUR, which was not represented and generally over-estimated, respectively. The maximum growth rate mu(m), was found to have a quadratic relationship with MC and a negative association with BA particle size. As a result, increasing MC up to 50% and using a smaller BA particle size of 8-12 mm was seen to maximize mu(m). The rate of hydrolysis K(h) was found to have a linear association with both MC and BA particle size. The model also estimated the initial readily biodegradable organic matter fraction, MB(0), and the slower biodegradable matter requiring hydrolysis, MH(0). The sum of MB(0) and MH(0) was associated with MC, W/BA ratio and the interaction between these two parameters, suggesting that O(2) availability was a key factor in determining the value of these two fractions. The study reinforced the idea that optimization of the physical characteristics of a compost mixture requires a holistic approach. 2010 Elsevier Ltd. All rights reserved.
Heys, D.W.; Stump, D.R.
1987-01-01
Variational calculations are described that use multi-parameter trial wave functions for the U(1) lattice gauge theory in two space dimensions, and for the XY model. The trial functions are constructed as the exponential of a linear combination of states from the strong-coupling basis of the model, with the coefficients treated as variational parameters. The expectation of the hamiltonian is computed by the Monte Carlo method, using a reweighting technique to evaluate expectation values in finite patches of the parameter space. The trial function for the U(1) gauge theory involves six variational parameters, and its weak-coupling behaviour is in reasonable agreement with theoretical expectations. (orig.)
Campolina, Daniel de Almeida Magalhães
2015-01-01
There is an uncertainty for all the components that comprise the model of a nuclear system. Assessing the impact of uncertainties in the simulation of fissionable material systems is essential for a realistic calculation that has been replacing conservative model calculations as the computational power increases. The propagation of uncertainty in a simulation using a Monte Carlo code by sampling the input parameters is recent because of the huge computational effort required. By analyzing the propagated uncertainty to the effective neutron multiplication factor (k eff ), the effects of the sample size, computational uncertainty and efficiency of a random number generator to represent the distributions that characterize physical uncertainty in a light water reactor was investigated. A program entitled GB s ample was implemented to enable the application of the random sampling method, which requires an automated process and robust statistical tools. The program was based on the black box model and the MCNPX code was used in and parallel processing for the calculation of particle transport. The uncertainties considered were taken from a benchmark experiment in which the effects in k eff due to physical uncertainties is done through a conservative method. In this work a script called GB s ample was implemented to automate the sampling based method, use multiprocessing and assure the necessary robustness. It has been found the possibility of improving the efficiency of the random sampling method by selecting distributions obtained from a random number generator in order to obtain a better representation of uncertainty figures. After the convergence of the method is achieved, in order to reduce the variance of the uncertainty propagated without increase in computational time, it was found the best number o components to be sampled. It was also observed that if the sampling method is used to calculate the effect on k eff due to physical uncertainties reported by
Large scale shell model calculations: the physics in and the physics out
Zuker, A.P.
1997-01-01
After giving a few examples of recent results of the (SM) 2 collaboration, the monopole modified realistic interactions to be used in shell model calculations are described and analyzed. Rotational motion is discussed in some detail, and some introductory remarks on level densities are made. (orig.)
"Shut up and calculate": the available discursive positions in quantum physics courses
Johansson, Anders; Andersson, Staffan; Salminen-Karlsson, Minna; Elmgren, Maja
2018-03-01
Educating new generations of physicists is often seen as a matter of attracting good students, teaching them physics and making sure that they stay at the university. Sometimes, questions are also raised about what could be done to increase diversity in recruitment. Using a discursive perspective, in this study of three introductory quantum physics courses at two Swedish universities, we instead ask what it means to become a physicist, and whether certain ways of becoming a physicist and doing physics is privileged in this process. Asking the question of what discursive positions are made accessible to students, we use observations of lectures and problem solving sessions together with interviews with students to characterize the discourse in the courses. Many students seem to have high expectations for the quantum physics course and generally express that they appreciate the course more than other courses. Nevertheless, our analysis shows that the ways of being a "good quantum physics student" are limited by the dominating focus on calculating quantum physics in the courses. We argue that this could have negative consequences both for the education of future physicists and the discipline of physics itself, in that it may reproduce an instrumental "shut up and calculate"-culture of physics, as well as an elitist physics education. Additionally, many students who take the courses are not future physicists, and the limitation of discursive positions may also affect these students significantly.
DARK ENERGY AND KEY PHYSICAL PARAMETERS OF CLUSTERS OF GALAXIES
Gennady S. Bisnovatyi-Kogan
2013-12-01
Full Text Available We study physics of clusters of galaxies embedded in the cosmic dark energy background. The equilibrium and stability of polytropic spheres with equation of state of the matter P = Kpγ, γ = 1 + 1/n, in presence of a non-zero cosmological constant is investigated. The equilibrium state exists only for central densities p0 larger than the critical value pc and there are no static solutions at p0
Syafriyono, S.; Caesario, D.; Swastika, A.; Adlan, Q.; Syafri, I.; Abdurrokhim, A.; Mardiana, U.; Mohamad, F.; Alfadli, M. K.; Sari, V. M.
2018-03-01
Rock physical parameters value (Vp and Vs) is one of fundamental aspects in reservoir characterization as a tool to detect rock heterogenity. Its response is depend on several reservoir conditions such as lithology, pressure and reservoir fluids. The value of Vp and Vs is controlled by grain contact and contact stiffness, a function of clay mineral content and porosity also affected by mineral composition. The study about Vp and Vs response within sandstone and its relationship with petrographic parameters has become important to define anisotrophy of reservoir characteristics distribution and could give a better understanding about local diagenesis that influence clastic reservoir properties. Petrographic analysis and Vp-Vs calculation was carried out to 12 core sample which is obtained by hand-drilling of the outcrop in Sukabumi area, West Java as a part of Bayah Formation. Data processing and interpretation of sedimentary vertical succession showing that this outcrop comprises of 3 major sandstone layers indicating fluvial depositional environment. As stated before, there are 4 petrographic parameters (sorting, roundness, clay mineral content, and grain contact) which are responsible to the differences of shear wave and compressional wave value in this outcrop. Lithology with poor-sorted and well- roundness has Vp value lower than well-sorted and poor-roundness (sub-angular) grain. For the sample with high clay content, Vp value is ranging from 1681 to 2000 m/s and could be getting high until 2190 to 2714 m/s in low clay content sample even though the presence of clay minerals cannot be defined neither as matrix nor cement. The whole sample have suture grain contact indicating telogenesis regime whereas facies has no relationship with Vp and Vs value because of the different type of facies show similar petrographic parameters after diagenesis.
Thermodynamic Calculations of Hydrogen-Oxygen Detonation Parameters for Various Initial Pressures
Bollinger, Loren E.; Edse, Rudolph
1961-01-01
Composition, temperature, pressure and density behind a stable detonation wave and its propagation rate have been calculated for seven hydrogen-oxygen mixture at 1, 5, 25 and 100 atm initial pressure, and at an initial temperature of 40C. For stoichiometric mixtures that calculations also include an initial temperature of 200C. According to these calculations the detonation velocities of hydrogen-oxygen mixtures increase with increasing initial pressure, but decrease slightly when the initial temperature is raised from 40 to 200 C. The calculated detonation velocities agree satisfactorily with values determined experimentally. These values will be published in the near future.
I. V. Novash
2015-01-01
Full Text Available This article describes the parameters calculation for the three-phase two-winding power transformer model taken from the SimPowerSystems library, which is the part of the MatLab- Simulink environment. Presented methodology is based on the power transformer nameplate data usage. Particular attention is paid to the power transformer magnetization curve para- meters calculation. The methodology of the three-phase two-winding power transformer model parameters calculation considering the magnetization curve nonlinearity isn’t presented in Russian-and English-language sources. Power transformers demo models described in the SimPowerSystems user’s guide have already calculated parameters, but without reference to the sources of their determination. A power transformer is a nonlinear element of the power system, that’s why for its performance analysis in different modes of operation is necessary to have the magnetization curve parameters.The process analysis during no-load energizing of the power transformer is of special interest. This regime is accompanied by the inrush current on the supply side of the power transformer, which is several times larger than the transformer rated current. Sharp rising of the magnetizing current is explained by the magnetic core saturation. Therefore, magnetiza- tion characteristic accounting during transformer no-load energizing modeling is a mandatory requirement. Article authors attempt to put all calculating formulas in a more convenient form and validate the power transformer nonlinear magnetization characteristics parameters calcu- lation. Inrush current oscillograms obtained during the simulation experiment confirmed the adequacy of the calculated model parameters.
Abd El-Moneim, A.
2003-07-01
The correlation between activation energy of ultrasonic relaxation process through the temperature range from 140 to 300 K and some physical properties has been investigated in pure TeO 2 and transition metal TeO 2-V 2O 5 and TeO 2-MoO 3 glasses according to Bridge and Patel's theory. The oxygen density (loss centers), number of two-well systems, hopping distance and mechanical relaxation time have been calculated in these glasses from the data of density, bulk modulus and stretching force constant of the glass. It has been found that the acoustic activation energy increased linearly with both the oxygen density and the number of two-well systems. The correlation between the acoustic activation energy and bulk modulus was achieved through the stretching force constant of the network and other structural parameters. Moreover, the experimental values of activation energy (V) agree well with those calculated from an empirical equation presented in this study in the form V=2.9×10 -7 F( F/ K) 3.37, where F is the stretching force constant of the glass and K is the experimental bulk modulus.
Estimation of static parameters based on dynamical and physical properties in limestone rocks
Ghafoori, Mohammad; Rastegarnia, Ahmad; Lashkaripour, Gholam Reza
2018-01-01
Due to the importance of uniaxial compressive strength (UCS), static Young's modulus (ES) and shear wave velocity, it is always worth to predict these parameters from empirical relations that suggested for other formations with same lithology. This paper studies the physical, mechanical and dynamical properties of limestone rocks using the results of laboratory tests which carried out on 60 the Jahrum and the Asmari formations core specimens. The core specimens were obtained from the Bazoft dam site, hydroelectric supply and double-curvature arch dam in Iran. The Dynamic Young's modulus (Ed) and dynamic Poisson ratio were calculated using the existing relations. Some empirical relations were presented to estimate uniaxial compressive strength, as well as static Young's modulus and shear wave velocity (Vs). Results showed the static parameters such as uniaxial compressive strength and static Young's modulus represented low correlation with water absorption. It is also found that the uniaxial compressive strength and static Young's modulus had high correlation with compressional wave velocity and dynamic Young's modulus, respectively. Dynamic Young's modulus was 5 times larger than static Young's modulus. Further, the dynamic Poisson ratio was 1.3 times larger than static Poisson ratio. The relationship between shear wave velocity (Vs) and compressional wave velocity (Vp) was power and positive with high correlation coefficient. Prediction of uniaxial compressive strength based on Vp was better than that based on Vs . Generally, both UCS and static Young's modulus (ES) had good correlation with Ed.
Frolov, A.M.
1986-01-01
Exact variational calculations are treated for few-particle systems in the exponential basis of relative coordinates using nonlinear parameters. The methods of step-by-step optimization and global chaos of nonlinear parameters are applied to calculate the S and P states of ppμ, ddμ, ttμ homonuclear mesomolecules within the error ≤±0.001 eV. The global chaos method turned out to be well applicable to nuclear 3 H and 3 He systems
Frolov, A M
1986-09-01
Exact variational calculations are treated for few-particle systems in the exponential basis of relative coordinates using nonlinear parameters. The methods of step-by-step optimization and global chaos of nonlinear parameters are applied to calculate the S and P states of pp..mu.., dd..mu.., tt..mu.. homonuclear mesomolecules within the error less than or equal to+-0.001 eV. The global chaos method turned out to be well applicable to nuclear /sup 3/H and /sup 3/He systems.
Comparison of two methods for calculating the P sorption capacity parameter in soils
Phosphorus (P) cycling in soils is an important process affecting P movement through the landscape. The P cycling routines in many computer models are based on the relationships developed for the EPIC model. An important parameter required for this model is the P sorption capacity parameter (PSP). I...
Large model-space calculation of the nuclear level density parameter
Agrawal, B.K.; Samaddar, S.K.; De, J.N.; Shlomo, S.
1998-01-01
Recently, several attempts have been made to obtain nuclear level density (ρ) and level density parameter (α) within the microscopic approaches based on path integral representation of the partition function. The results for the inverse level density parameter K es and the level density as a function of excitation energy are presented
New theoretical development for the calculating of physical properties of D2O
Moreira, Osvaldo
2011-01-01
In this work we have developed a new method for calculating the physical properties of heavy water, D 2 O, using the Helmholtz free energy state function, A = U − T S, exclusively for this molecule. The state function has been calculated as ā = ā 0 +ā 1 (specific dimensionless values), where ā 0 is related to the properties of heavy water in gaseous state and ā 1 describes the liquid state. The canonical variables of the state function are absolute temperature and volume. To calculate the physical properties defining absolute pressure and temperature, here a variable change method was developed, based on the solution of a differential equation (function ζ) using numerical algorithms (scaling and Newton-Raphson). Physical quantities calculated are: density ϱ(specific volume υ), specific enthalpy h and entropy s. The results obtained agree completely with the values calculated by the National Institute of Standards and Technology (NIST). In this report it has also proposed an adjustment function to calculate the saturation absolute temperature of heavy water as a function of the pressure: T s (p) = exp[a·b(p)], where a is a vector of constant coefficients and b a vector function of pressure, using theoretical values and extending the wording proposed by the Oak Ridge National Laboratory. The new setting has an error less than 0.03%. (author)
Developments in Sensitivity Methodologies and the Validation of Reactor Physics Calculations
Giuseppe Palmiotti
2012-01-01
Full Text Available The sensitivity methodologies have been a remarkable story when adopted in the reactor physics field. Sensitivity coefficients can be used for different objectives like uncertainty estimates, design optimization, determination of target accuracy requirements, adjustment of input parameters, and evaluations of the representativity of an experiment with respect to a reference design configuration. A review of the methods used is provided, and several examples illustrate the success of the methodology in reactor physics. A new application as the improvement of nuclear basic parameters using integral experiments is also described.
Lorenz-Meyer, W.
1977-01-01
In connection with the question on the applicability of test results obtained from cryogenic wind tunnels to the large-scale model the similarity parameter is referred to. A simple method is given for calculating the similarity parameter. From the numerical values obtained it can be deduced that nitrogen behaves practically like an ideal gas when it is close to the saturation point and in a pressure range up to 4 bar. The influence of this parameter on the pressure distribution of a supercritical profile confirms this finding.
Journal of the American Academy of Child & Adolescent Psychiatry, 2009
2009-01-01
An introduction for any medical health clinician on the knowledge and skills that are needed for the psychiatric assessment and management of physically ill children and adolescents is presented. These parameters are presented to assist clinicians in psychiatric decision making.
Mowlavi, A. A.; Binesh, A.; Moslehitabar, H.
2006-01-01
Palladium-103 ( 103 Pd) is a brachytherapy source for cancer treatment. The Monte Carlo codes are usually applied for dose distribution and effect of shieldings. Monte Carlo calculation of dose distribution in water phantom due to a MED3633 103 Pd source is presented in this work. Materials and Methods: The dose distribution around the 10 3Pd Model MED3633 located in the center of 30*30*30 m 3 water phantom cube was calculated using MCNP code by the Monte Carlo method. The percentage depth dose variation along the different axis parallel and perpendicular to the source was also calculated. Then, the isodose curves for 100%, 75%, 50% and 25% percentage depth dose and dosimetry parameters of TG-43 protocol were determined. Results: The results show that the Monte Carlo Method could calculate dose deposition in high gradient region, near the source, accurately. The isodose curves and dosimetric characteristics obtained for MED3633 103 Pd source are in good agreement with published results. Conclusion: The isodose curves of the MED3633 103 Pd source have been derived form dose calculation by MCNP code. The calculated dosimetry parameters for the source agree quite well with their Monte Carlo calculated and experimental measurement values
Šiupšinskas, Laimonas
2007-01-01
Physical activity level of students is decreasing. Students are specific population group with similar patterns of habitual physical activity influenced by study process. That formed requirement to search for a new ways to assess physical activity of the students indirectly. Offered method assesses level of physical health, measures physical fitness and evaluates body composition. The aim of the study is to evaluate indirectly measured health-enhanced physical activity of the students by phys...
Ivo, Kljenak; Miroslav, Babic; Borut, Mavko
2007-01-01
The possibility of simulating adequately the flow circulation within a nuclear power plant containment using a lumped-parameter code is considered. An experiment on atmosphere mixing and stratification, which was performed in the containment experimental facility TOSQAN at IRSN (Institute of Radioprotection and Nuclear Safety) in Saclay (France), was simulated with the CFD (Computational Fluid Dynamics) code CFX4 and the lumped-parameter code CONTAIN. During some phases of the experiment, steady states were achieved by keeping the boundary conditions constant. Two steady states during which natural convection was the dominant gas flow mechanism were simulated independently. The nodalization of the lumped-parameter model was based on the flow pattern, simulated with the CFD code. The simulation with the lumped-parameter code predicted basically the same flow circulation patterns within the experimental vessel as the simulation with the CFD code did. (authors)
Pavlova, Anna; Parks, Jerry M; Gumbart, James C
2018-02-13
Corrinoid cofactors such as cobalamin are used by many enzymes and are essential for most living organisms. Therefore, there is broad interest in investigating cobalamin-protein interactions with molecular dynamics simulations. Previously developed parameters for cobalamins are based mainly on crystal structure data. Here, we report CHARMM-compatible force field parameters for several corrinoids developed from quantum mechanical calculations. We provide parameters for corrinoids in three oxidation states, Co 3+ , Co 2+ , and Co 1+ , and with various axial ligands. Lennard-Jones parameters for the cobalt center in the Co(II) and Co(I) states were optimized using a helium atom probe, and partial atomic charges were obtained with a combination of natural population analysis (NPA) and restrained electrostatic potential (RESP) fitting approaches. The Force Field Toolkit was used to optimize all bonded terms. The resulting parameters, determined solely from calculations of cobalamin alone or in water, were then validated by assessing their agreement with density functional theory geometries and by analyzing molecular dynamics simulation trajectories of several corrinoid proteins for which X-ray crystal structures are available. In each case, we obtained excellent agreement with the reference data. In comparison to previous CHARMM-compatible parameters for cobalamin, we observe a better agreement for the fold angle and lower RMSD in the cobalamin binding site. The approach described here is readily adaptable for developing CHARMM-compatible force-field parameters for other corrinoids or large biomolecules.
Parameters Calculation of ZnO Surge Arrester Models by Genetic Algorithms
A. Bayadi
2006-09-01
Full Text Available This paper proposes to provide a new technique based on the genetic algorithm to obtain the best possible series of values of the parameters of the ZnO surge arresters models. The validity of the predicted parameters is then checked by comparing the results predicted with the experimental results available in the literature. Using the ATP-EMTP package an application of the arrester model on network system studies is presented and discussed.
Zhu, Hongchun; Cai, Lijie; Liu, Haiying; Huang, Wei
2016-01-01
Multi-scale image segmentation and the selection of optimal segmentation parameters are the key processes in the object-oriented information extraction of high-resolution remote sensing images. The accuracy of remote sensing special subject information depends on this extraction. On the basis of WorldView-2 high-resolution data, the optimal segmentation parameters methodof object-oriented image segmentation and high-resolution image information extraction, the following processes were conducted in this study. Firstly, the best combination of the bands and weights was determined for the information extraction of high-resolution remote sensing image. An improved weighted mean-variance method was proposed andused to calculatethe optimal segmentation scale. Thereafter, the best shape factor parameter and compact factor parameters were computed with the use of the control variables and the combination of the heterogeneity and homogeneity indexes. Different types of image segmentation parameters were obtained according to the surface features. The high-resolution remote sensing images were multi-scale segmented with the optimal segmentation parameters. Ahierarchical network structure was established by setting the information extraction rules to achieve object-oriented information extraction. This study presents an effective and practical method that can explain expert input judgment by reproducible quantitative measurements. Furthermore the results of this procedure may be incorporated into a classification scheme. PMID:27362762
Sukhanov, AY
2017-02-01
We present an approximation Voigt contour for some parameters intervals such as the interval with y less than 0.02 and absolute value x less than 1.6 gives a simple formula for calculating and relative error less than 0.1%, and for some of the intervals suggetsted to use Hermite quadrature.
Physically Active Men Show Better Semen Parameters than Their Sedentary Counterparts.
Lalinde-Acevedo, Paula C; Mayorga-Torres, B Jose Manuel; Agarwal, Ashok; du Plessis, Stefan S; Ahmad, Gulfam; Cadavid, Ángela P; Cardona Maya, Walter D
2017-10-01
The quality of semen depends upon several factors such as environment, life style, physical activity, age, and occupation. The aim of this study was to analyze and compare the conventional and functional semen parameters in men practicing vigorous physical activity to those of sedentary men. In this descriptive cross-sectional study, semen samples of 17 physically active men and 15 sedentary men were collected for analysis. Semen analysis was performed according to the World Health Organization (WHO) guidelines, while functional parameters were evaluated by flow cytometry. Results showed that several semen parameters (semen volume, viability, progressive motility, total motility, normal morphology, and moribund cells) were superior in the physically active group in comparison with the sedentary group. Semen parameters such as viability, progressive motility and total motility, as well as the percentage of moribund spermatozoa were signiﬁcantly different between both groups. However, sperm DNA damage, lipid peroxidation and mitochondrial potential were not significantly different among the groups. Nevertheless, the physical activity shows better semen parameters than sedentary group. Taken together, our results demonstrate that regular physical activity has beneficial impact in sperm fertility parameters and such a life style can enhance the fertility status of men. Copyright© by Royan Institute. All rights reserved.
Okuducu, S.; Sarac, H.; Akti, N. N.; Boeluekdemir, M. H.; Tel, E.
2010-01-01
In this study the nuclear energy level density based on nuclear collective excitation mechanism has been identified in terms of the low-lying collective level bands at near the neutron binding energy. Nuclear level density parameters of some light deformed medical radionuclides used widely in medical applications have been calculated by using different collective excitation modes of observed nuclear spectra. The calculated parameters have been used successfully in estimation of the neutron-capture cross section basic data for the production of new medical radionuclides. The investigated radionuclides have been considered in the region of mass number 40< A< 100. The method used in the present work assumes equidistance spacing of the collective coupled state bands of the interest radionuclides. The present calculated results have been compared with the compiled values from the literatures for s-wave neutron resonance data.
Lessard, E.T.; Skrable, K.W.
1981-01-01
Two dosimetric models, the catenary compartmental model and the slug flow model are examined using three sets of physiological parameters. The impact of physiological parameters on the dosimetry of the tract is illustrated by comparing calculated maximum permissible daily activity ingestion rates for single, unabsorbed, particle emitting radionuclides with an effective energy term of unity. The conclusions drawn from this intercomparison of six different cases are: (1) Current dosimetric models which use physiological parameters described in this article do not significantly disagree, and (2) For the determination of average dose equivalent rates to segments of the tract due to chronic, long term ingestion of any radionuclide, the catenary compartmental model is a mathematically simpler approach. The catenary model in addition has certain advantages for the calculation of the photon dose contribution to one segment from cumulated activity (disintegrations) in another segment
On the Methodology to Calculate the Covariance of Estimated Resonance Parameters
Becker, B.; Kopecky, S.; Schillebeeckx, P.
2015-01-01
Principles to determine resonance parameters and their covariance from experimental data are discussed. Different methods to propagate the covariance of experimental parameters are compared. A full Bayesian statistical analysis reveals that the level to which the initial uncertainty of the experimental parameters propagates, strongly depends on the experimental conditions. For high precision data the initial uncertainties of experimental parameters, like a normalization factor, has almost no impact on the covariance of the parameters in case of thick sample measurements and conventional uncertainty propagation or full Bayesian analysis. The covariances derived from a full Bayesian analysis and least-squares fit are derived under the condition that the model describing the experimental observables is perfect. When the quality of the model can not be verified a more conservative method based on a renormalization of the covariance matrix is recommended to propagate fully the uncertainty of experimental systematic effects. Finally, neutron resonance transmission analysis is proposed as an accurate method to validate evaluated data libraries in the resolved resonance region
Roux, A.
2001-01-01
The diversity of radiological accidents makes difficult the medical prognosis and the therapy choice from only clinical observations. To complete this information, it is important to know the global dose received by the organism and the dose distributions in depth in tissues. The dose estimation can be made by a physical reconstruction of the accident with the help of tools based on experimental techniques or on calculation. The software of the geometry construction (M.G.E.D.), associated to the Monte-Carlo code of photons and neutrons transport (M.O.R.S.E.) replies these constraints. An important result of this work is to determine the principal parameters to know in function of the accident type, as well as the precision level required for these parameters. (N.C.)
Bechmann, Iben Ellegaard; Jensen, H.S.; Bøknæs, Niels
1998-01-01
Physical, chemical and sensory quality parameters were determined for 115 cod (Gadus morhua) samples stored under varying frozen storage conditions. Five different process parameters (period of frozen storage, frozen storage. temperature, place of catch, season for catching and state of rigor) were...... varied systematically at two levels. The data obtained were evaluated using the multivariate methods, principal component analysis (PCA) and partial least squares (PLS) regression. The PCA models were used to identify which process parameters were actually most important for the quality of the frozen cod....... PLS models that were able to predict the physical, chemical and sensory quality parameters from the process parameters of the frozen raw material were generated. The prediction abilities of the PLS models were good enough to give reasonable results even when the process parameters were characterised...
Sornek Krzysztof
2016-01-01
Full Text Available The proper design of renewable energy based systems is really important to provide their efficient and safe operation. The aim of this paper is to compare the results obtained during traditional static calculations, with the results of dynamic simulations. For this reason, simulations of solar water heating (SWH system, designed for a typical residential building, were conducted in the TRNSYS (Transient System Simulation Tool. Carried out calculations allowed to determine the heat generation in the discussed system as well as to estimate the efficiency of considered installation. Obtained results were compared with the results from other available tool based on the static calculations. It may be concluded, that using dynamic simulations at the designing stage of renewable energy based systems may help to avoid many exploitation problems (including low efficiency, overheating etc. and allows to provide safe exploitation of such installations.
Calculation of the apparent neutron parameters in a borehole geometry for neutron porosity tools
Woznicka, U.; Drabina, A.
2001-01-01
This paper presents the next step of a development of the theoretical solutions, which gives a possibility to calculate the apparent neutron slowing down and migration lengths in the three region cylindrical system which represents the borehole, the intermediate zone (e.g. mud cake at the borehole walls), and the geological formation. A solution of the neutron diffusion equation in energy two-group approach for spatial moments of the neutron flux is given for the three-region cylindrical coaxial geometry. The influence of the intermediate zone is presented. The numerical code MOM3 has been written to calculate the apparent slowing down and migration lengths for the three-region cylindrical system as mentioned above. Additionally the MCNP calculation for the three-region borehole geometry is presented in the paper
Parameter-free calculation of K alpha chemical shifts for Al, Si, and Ge oxides
Lægsgaard, Jesper
2001-01-01
The chemical shifts of the K alpha radiation line from Al, Si, and Ge ions between their elemental and oxide forms are calculated within the framework of density functional theory using ultrasoft pseudopotentials. It is demonstrated that this theoretical approach yields quantitatively accurate...... results fur the systems investigated, provided that relaxations of the valence electrons upon the core-hole transition are properly accounted for. Therefore, such calculations provide a powerful tool for identification of impurity states based on x-ray fluorescence data. Results for an Al impurity...
Paratte, J.M.; Frueh, R.; Kasemeyer, U.; Kalugin, M.A.; Timm, W.; Chawla, R.
2006-01-01
Measurements in the CROCUS reactor at EPFL, Lausanne, are reported for the critical water level and the inverse reactor period for several different sets of delayed supercritical conditions. The experimental configurations were also calculated by four different calculation methods. For each of the supercritical configurations, the absolute reactivity value has been determined in two different ways, viz.: (i) through direct comparison of the multiplication factor obtained employing a given calculation method with the corresponding value for the critical case (calculated reactivity: ρ calc ); (ii) by application of the inhour equation using the kinetic parameters obtained for the critical configuration and the measured inverse reactor period (measured reactivity: ρ meas ). The calculated multiplication factors for the reference critical configuration, as well as ρ calc for the supercritical cases, are found to be in good agreement. However, the values of ρ meas produced by two of the applied calculation methods differ appreciably from the corresponding ρ calc values, clearly indicating deficiencies in the kinetic parameters obtained from these methods
Mbagwu, J.S.C.
1994-05-01
Among the many models developed for monitoring the infiltration process those of Philip and Kostiakov have been studied in detail because of their simplicity and the ease of estimating their fitting parameters. The important soil physical factors influencing the fitting parameters in these infiltration models are reported in this study. The results of the study show that the single most important soil property affecting the fitting parameters in these models is the effective porosity. 36 refs, 2 figs, 5 tabs
Progress on reference input parameter library for nuclear model calculations of nuclear data (III)
Su Zongdi; Liu Jianfeng; Huang Zhongfu
1997-01-01
A new set of the average neutron resonance spacings D 0 and neutron strength functions S 0 for 309 nuclei were reestimated on the basis of the resolved resonance parameters reevaluated from BNL-325, ENDF/B-6, JEF-2, and JENDL-3, and the cumulative number N 0 of low low lying levels for 344 nuclei were also reevaluated by means of histograms. Three sets of level density parameters for the Gilbert-Cameron (GC) formula, back-shifted Fermi gas model(BS) and generated superfluid model (GSM) have been reesitmated by fitting the D 0 and N 0 values of CENPL.LRD-2
Cleary, David A.
2014-01-01
The usefulness of the JANAF tables is demonstrated with specific equilibrium calculations. An emphasis is placed on the nature of standard chemical potential calculations. Also, the use of the JANAF tables for calculating partition functions is examined. In the partition function calculations, the importance of the zero of energy is highlighted.
Physically Active Men Show Better Semen Parameters than Their Sedentary Counterparts
Lalinde-Acevedo, Paula C.; Mayorga-Torres, B. Jose Manuel; Agarwal, Ashok; du Plessis, Stefan S.; Ahmad, Gulfam; Cadavid, Ángela P.; Cardona Maya, Walter D.
2017-01-01
Background The quality of semen depends upon several factors such as environment, life style, physical activity, age, and occupation. The aim of this study was to analyze and compare the conventional and functional semen parameters in men practicing vigorous physical activity to those of sedentary men. Materials and Methods In this descriptive cross-sectional study, semen samples of 17 physically active men and 15 sedentary men were collected for analysis. Semen analysis was performe...
Calculating the best parameters B0 and B1 for the IRI profile from ionograms
Huang Xueqin; Reinisch, B.W.
1997-01-01
This technical note describes the software tools developed at the University of Massachusetts Lowell for the calculation of the 'best' B0 and B1 for the IRI analytic function that describes the bottomside profile of the F2 layer. A step-by-step procedure is given starting with ionograms from Digisondes or any other ionosonde. 9 refs, 4 figs, 1 tab
Parameter calculation tool for the application of radiological dose projection codes
Galindo G, I. F.; Vergara del C, J. A.; Galvan A, S. J.; Tijerina S, F.
2016-09-01
The use of specialized codes to estimate the radiation dose projection to an emergency postulated event at a nuclear power plant requires that certain plant data be available according to the event being simulated. The calculation of the possible radiological release is the critical activity to carry out the emergency actions. However, not all of the plant data required are obtained directly from the plant but need to be calculated. In this paper we present a computational tool that calculates the plant data required to use the radiological dose estimation codes. The tool provides the required information when there is a gas emergency venting event in the primary containment atmosphere, whether well or dry well and also calculates the time in which the spent fuel pool would be discovered in the event of a leak of water on some of the walls or floor of the pool. The tool developed has mathematical models for the processes involved such as: compressible flow in pipes considering area change and for constant area, taking into account the effects of friction and for the case of the spent fuel pool hydraulic models to calculate the time in which a container is emptied. The models implemented in the tool are validated with data from the literature for simulated cases. The results with the tool are very similar to those of reference. This tool will also be very supportive so that in postulated emergency cases can use the radiological dose estimation codes to adequately and efficiently determine the actions to be taken in a way that affects as little as possible. (Author)
Branda, M.M.; Ferullo, R.; Castellani, N.J.
1990-01-01
The application of an atomic Hartree-Fock-Slater method is exposed in the present work for the simultaneous obtainment of all parameters used in the extended Hueckel method with charge interaction (IEH): The diagonal elements of the Hamiltonian, the constants of the quadratic relation between. (Author). 16 refs., 3 tabs
Universal algorithms and programs for calculating the motion parameters in the two-body problem
Bakhshiyan, B. T.; Sukhanov, A. A.
1979-01-01
The algorithms and FORTRAN programs for computing positions and velocities, orbital elements and first and second partial derivatives in the two-body problem are presented. The algorithms are applicable for any value of eccentricity and are convenient for computing various navigation parameters.
Gillete, V.H.; Patino, N.E.; Granada, J.E.; Mayer, R.E.
1988-01-01
Using a synthetic scattering function which describes the interaction of neutrons with molecular gases we provide analytical expressions for zero-and first-order scattering kernels, σ 0 (E 0 →E), σ 1 (E 0 →E), and total cross section σ 0 (E 0 ). Based on these quantities, we have performed calculations of thermalization parameters and transport coefficients for H 2 O, D 2 O, C 6 H 6 and (CH 2 ) n at room temperature. Comparasion of such values with available experimental data and other calculations is satisfactory. We also generated nuclear data libraries for H 2 O with 47 thermal groups at 300K and performed some benchmark calculations ( 235 U, 239 Pu, PWR cell and typical APWR cell); the resulting reactivities are compared with experimental data and ENDF/B-IV calculations. (author) [pt
Tiszbierek Agnieszka
2017-01-01
Full Text Available An elaborated digital computer programme supporting the time-consuming process of selecting the importance rank of construction and operation parameters by means of stating optimum sets is based on the Quine – McCluskey algorithm of minimizing individual partial multi-valued logic functions. The example with real time data, calculated by means of the programme, showed that among the obtained optimum sets there were such which had a different number of real branches after being presented on the multi-valued logic decision tree. That is why an idea of elaborating another functionality of the programme – a module calculating the number of branches of real, multi-valued logic decision trees presenting optimum sets chosen by the programme was pursued. This paper presents the idea and the method for developing a module calculating the number of branches, real for each of optimum sets indicated by the programme, as well as to the calculation process.
Calculation of high-pressure argon plasma parameters produced by excimer laser
Tsuda, Norio; Yamada, Jun
2000-01-01
When a XeCl excimer laser light was focused in a high-pressure argon gas up to 150 atm, a dense plasma developed not only backward but also forward. It is important to study on the electron density and temperature of the laser-induced plasma in the high-pressure gas. The electron density and temperature in high-pressure argon plasma produced by XeCl excimer laser has been calculated and compared with the experimental data. (author)
Calculations of dosimetric parameter and REM meter response for BE(d, n) source
Chen Changmao
1988-01-01
Based on the recent data about neutron spectra, the average energy, effictive energy and conversion coefficient of fluence to dose equivalent are calculated for some Be (α, n) neutron sources which have differene types and structures. The responses of 2202D and 0075 REM meter for thses spectral neutrons are also estimated. The results indicate that the relationship between average energy and conversion coefficient or REM meter responses can be described by simple functions
Mamikonyan, S.V.; Berezkin, V.V.; Lyubimova, S.V.; Svetajlo, Yu.N.; Shchekin, K.I.
1978-01-01
A method to derive multiple regression equations for X-ray radiometric analysis is described. Te method is realized in the form of the REGRA program in an algorithmic language. The subprograms included in the program are describe. In analyzing cement for Mg, Al, Si, Ca and Fe contents as an example, the obtainment of working equations in the course of calculations by the program is shown to simpliy the realization of computing devices in instruments for X-ray radiometric analysis
A computer code for calculating neutron cross-sections from resonance parameter data
Mill, A.J.
1979-08-01
A computer code, XSEC, has been written which calculates neutron cross-sections from resonance data. Although the program was originally written in order to identify neutron 'windows' in enriched nuclides, it may be used to evaluate the total neutron cross-section of any medium mass nuclide at intermediate energies. XSEC has proved very useful in identifying suitable nuclides for use as neutron filters at intermediate energies. (author)
Okhrimenko, I.P.
1984-01-01
The dynamical equations of the algebraic version of the resonating group method are used to determine the positions and the widths of quasi-stationary states or to find the poles of the S-matrix in the fourth quadrant of the K-plane. Concrete calculations are performed by the example of an α-decay of 8 Be. A comparison with the results of the other authors and experiment is made
Sadeghi, Mahdi; Raisali, Gholamreza; Hosseini, S. Hamed; Shavar, Arzhang
2008-01-01
This article presents a brachytherapy source having 103 Pd adsorbed onto a cylindrical silver rod that has been developed by the Agricultural, Medical, and Industrial Research School for permanent implant applications. Dosimetric characteristics (radial dose function, anisotropy function, and anisotropy factor) of this source were experimentally and theoretically determined in terms of the updated AAPM Task group 43 (TG-43U1) recommendations. Monte Carlo simulations were used to calculate the dose rate constant. Measurements were performed using TLD-GR200A circular chip dosimeters using standard methods employing thermoluminescent dosimeters in a Perspex phantom. Precision machined bores in the phantom located the dosimeters and the source in a reproducible fixed geometry, providing for transverse-axis and angular dose profiles over a range of distances from 0.5 to 5 cm. The Monte Carlo N-particle (MCNP) code, version 4C simulation techniques have been used to evaluate the dose-rate distributions around this model 103 Pd source in water and Perspex phantoms. The Monte Carlo calculated dose rate constant of the IRA- 103 Pd source in water was found to be 0.678 cGy h -1 U -1 with an approximate uncertainty of ±0.1%. The anisotropy function, F(r,θ), and the radial dose function, g(r), of the IRA- 103 Pd source were also measured in a Perspex phantom and calculated in both Perspex and liquid water phantoms
Capote Noy, Roberto; Simakov, Stanislav; Goriely, Stephane; Hilaire, Stephane; Iwamoto, Osamu; Kawano, Toshihiko; Koning, Arjan
2014-12-01
A Consultants’ Meeting on “Recommended Input Parameters for Fission Cross-Section Calculations” was held at IAEA Headquarters, Vienna, Austria to define the scope, deliverables and appropriate work programme of a possible Coordinated Research Project (CRP) on the subject. Presentations are available online at https://www-nds.iaea.org/indexmeeting-crp/CM-RIPL-fission/. A new CRP was endorsed to recommend a comprehensive set of fission input parameters needed for the modelling of fission cross sections. Special attention will be given to the modelling of photon and nucleon induced reactions on actinides with emphasis on incident energies below 30 MeV. The goals and detailed deliverables of the planned CRP were proposed. A Hauser-Feshbach code intercomparison was recommended. (author)
The using of model calculations for the optimisation of the virtual impactor parameters
Kravchuk, T.A.; Lyubinskij, N.N.; Melenevskij, A.Eh.; Shcherbin, V.N.
2000-01-01
Some characteristics of virtual impactors have been determined by numerical solution of Navier-Stoces equations and the equations of motion of the particles. The effect of the nozzle Reynolds number, the fractioning of flows passing through the impactor, collection probe diameter, nozzle throat length, nozzle - to -collection probe distance and probe entrance form on heavy and light particle collection efficiencies has been studied. It was found that some particles would impact on the inner surface of the collection probe. The results show that the most parameters with the exception of the flow fractioning have little effect on the heavy particle collection efficiency. And vice versa the effect on collection probe losses was significant for the most of these parameters
A microscopic calculation of potentials and inertia parameters for heavy-ion collisions
Flocard, H.; Vautherin, D.; Heenen, P.H.
1979-09-01
Within the adiabatic time dependent Hartree-Fock formalism, the potential V(R) and the inertia parameter M(R) corresponding to the symmetric heavy-ion collisions 12 C+ 12 C and 16 O+ 16 O are computed. It is found that the mass M(R) exhibits very sharp peaks. These peaks are shown to provide a plausible mechanism to explain the occurrence of quasi-molecular resonances
Dračínský, Martin; Bouř, Petr; Hodgkinson, P.
2016-01-01
Roč. 12, č. 3 (2016), s. 968-973 ISSN 1549-9618 R&D Projects: GA ČR GA15-11223S; GA ČR GA15-09072S; GA ČR(CZ) GA16-05935S Institutional support: RVO:61388963 Keywords : short hydrogen bonds * density functional theory * spin coupling constants Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.245, year: 2016
The physical properties of Santowax 'R' for heat transfer calculations (AERE R/M 183 revised)
Bowring, R.W.; Garton, D.A.; Kinneir, J.H.
1961-03-01
Values of the following physical properties of Santowax 'R' are presented in graphical and/or tabular form in both English and Metric units: Vapour Pressure, Specific heat, Enthalpy, Density, Dynamic viscosity, Kinematic viscosity, Thermal conductivity, Prandtl number, Surface tension, Latent heat of vaporisation, Critical properties, Gas solubilities. The data were obtained by new experimental measurements, by calculation or from the published literature. Wherever possible an estimate of the probable error is given. Conversion factors and Tables are also presented to facilitate the conversion of any of the properties to convenient units required for calculations. (author)
Indry Septiana Novitasari; Yosaphat Sumardi; Widarto
2014-01-01
The experiment existing parameters physics for supporting of in vivo and in vitro test facility of Boron Neutron Capture Therapy (BNCT) preliminary study at the piercing radial beam port has been done. The existing experiments is needed for determining that the parameter physics is fulfill the BNCT method requirement. To realize the existing experiment have been done by design analysis, methodology, calculation method and some procedure related with radiation safety analysis and environment. Preparation for existing experiment physics such as foil detector of Gold (Au) should be irradiated for 30 minute, irradiation instrument and procedure related with the experiment for radiation safety. (author)
Sukhovoj, A.M.; Khitrov, V.A.; Grigor'ev, E.P.
2002-01-01
The level density and radiative strength functions which accurately reproduce the experimental intensity of two- step cascades after thermal neutron capture and the total radiative widths of the compound states were applied to calculate the total γ-ray spectra from the (n,γ) reaction. In some cases, analysis showed far better agreement with experiment and gave insight into possible ways in which these parameters need to be corrected for further improvement of calculation accuracy for the cascade γ-decay of heavy nuclei. (author)
Fawcett, B.C.; Mason, H.E.
1989-02-01
This report presents details of a new method to enable the computation of collision strengths for complex ions which is adapted from long established optimisation techniques previously applied to the calculation of atomic structures and oscillator strengths. The procedure involves the adjustment of Slater parameters so that they determine improved energy levels and eigenvectors. They provide a basis for collision strength calculations in ions where ab initio computations break down or result in reducible errors. This application is demonstrated through modifications of the DISTORTED WAVE collision code and SUPERSTRUCTURE atomic-structure code which interface via a transformation code JAJOM which processes their output. (author)
Glushkov, A.V.
1994-01-01
Based on the method of effective potential involving the new polarization interaction potential calculated from polarization diagrams of the perturbation theory in the Thomas-Fermi approximation, the main parameters of the interatomic potentials (equilibrium distances, potential well depth) are evaluated for a system consisting of an alkali atom in the ground and excited states and of a mercury atom. The results of calculations of quasi-molecular terms for the A-Hg system, where A = Na, Cs, Fr, are reported, some of which are obtained for the first time. A comparison is made with available experimental and theoretical data. 29 refs., 2 figs., 1 tab
Ben-David, M.; Inberg, A.; Katzir, A.; Croitoru, N.
1999-01-01
The modification of the laser source beam quality is one of the important factors effect the delivery of laser radiation by a waveguide. In this paper the results of input radiation coupling, radius of bending, length, cross section diameter, waveguide internal wall roughness and coupling lens focal length influence on the beam shape delivered from the flexible hollow waveguides are presented. The conditions for which the beam shape is near to that of the source were found. A theoretical model for the radiation propagation gives quantitative representation of relation between attenuation, beam profile, divergence and above indicated parameters was developed. In this model was supposed that the guiding is produced by multiple incidences on a metal (silver) layer and a dielectric (silver iodine) over layer, by refraction and reflection. The propagation of the rays was calculated using the physical laws of the geometrical optics. For the scattering calculations a random distribution of roughness centers on dielectric layer surface was considered. It was also supposed that the value of the cross section internal diameter (ID=d) was much larger than the transmitted wavelength. The experimental results have shown that losses due to absorption of the propagated radiation in the guiding layers, mainly (AgI), generate satellites of the laser source delivered fundamental Gaussian beam. Increasing of the hollow waveguide internal diameter decreases the attenuation and increases the deviation of beam shape from Gaussian. Off center coupling produce decreasing of the fundamental mode height and generation of the coupled Gaussian beam satellites. The waveguide internal wall roughness produce losses of the coupled radiation and beam profile deviations from that of the laser source. A good correspondence between the theoretical and experimental results obtained
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
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.
Ab Initio Calculation of Hyperfine Interaction Parameters: Recent Evolutions, Recent Examples
Cottenier, Stefaan; Vanhoof, Veerle; Torumba, Doru; Bellini, Valerio; Cakmak, Mehmet; Rots, Michel
2004-01-01
For some years already, ab initio calculations based on Density Functional Theory (DFT) belong to the toolbox of the field of hyperfine interaction studies. In this paper, the standard ab initio approach is schematically sketched. New features, methods and possibilities that broke through during the past few years are listed, and their relation to the standard approach is explained. All this is illustrated by some highlights of recent ab initio work done by the Nuclear Condensed Matter Group at the K.U.Leuven.
Utilization of the Nelkin model in a Hammer computer code for calculation the reactor parameters
Leal, L.C.
1980-07-01
The possibility of modifying the HAMMER code, in the thermal part, by changing the thermal neutron scattering Kernel of its library for another one calculated in a subprogramm which can be incorporated to the code, is studied. This subprogramm uses the original version of the Nelkin model instead of its approximation which is used in the HAMMER. It has the advantage of giving the values of the Kernel for any temperature of the reactor for the approximations P 0 , P 1 , P 2 and P 3 . (Author) [pt
Relativistic calculations of screening parameters and atomic radii of neutral atoms
Guerra, M.; Amaro, P.; Santos, J. P.; Indelicato, P.
2017-09-01
Calculations of the effective nuclear charge for elements with 1 ≤ Z ≤ 118 have been performed in a Dirac-Fock approach including all relativistic effects as well as contributions from quantum electrodynamics. Maximum charge density for every subshell of every element in the periodic table was also computed in the same framework as well as atomic radii based on the total charge density. Results were compared with the extensively cited works of Clementi et al., obtained in the 1960s with Roothan's self-consistent-field method.
Rowland, D R
2006-01-01
Introductory courses covering modern physics sometimes introduce some elementary ideas from general relativity, though the idea of a geodesic is generally limited to shortest Euclidean length on a curved surface of two spatial dimensions rather than extremal aging in spacetime. It is shown that Epstein charts provide a simple geometric picture of geodesics in one space and one time dimension and that for a hypothetical uniform gravitational field, geodesics are straight lines on a planar diagram. This means that the properties of geodesics in a uniform field can be calculated with only a knowledge of elementary geometry and trigonometry, thus making the calculation of some basic results of general relativity accessible to students even in an algebra-based survey course on physics
Sushardjanti Felasari
2003-01-01
Full Text Available This research examines the accuracy of computer programmes to simulate the illuminance level in atrium buildings compare to the measurement of those in physical models. The case was taken in atrium building with 4 types of roof i.e. pitched roof, barrel vault roof, monitor pitched roof (both monitor pitched roof and monitor barrel vault roof, and north light roof (both with north orientation and south orientation. The results show that both methods have agreement and disagreement. They show the same pattern of daylight distribution. In the other side, in terms of daylight factors, computer simulation tends to underestimate calculation compared to physical model measurement, while for average and minimum illumination, it tends to overestimate the calculation.
Ericsson, Jonas; Husmark, Teodor; Mathiesen, Christoffer; Sepahvand, Benjamin; Borck, Øyvind; Gunnarsson, Linda; Lydmark, Pär; Schröder, Elsebeth
2016-01-01
To increase public awareness of theoretical materials physics, a small group of high school students is invited to participate actively in a current research projects at Chalmers University of Technology. The Chalmers research group explores methods for filtrating hazardous and otherwise unwanted molecules from drinking water, for example by adsorption in active carbon filters. In this project, the students use graphene as an idealized model for active carbon, and estimate the energy of adsorption of the methylbenzene toluene on graphene with the help of the atomic-scale calculational method density functional theory. In this process the students develop an insight into applied quantum physics, a topic usually not taught at this educational level, and gain some experience with a couple of state-of-the-art calculational tools in materials research.
Parameters affecting the luminescence of nanodiamond particles:Quantum chemical calculations
Kovalenko, Alexander; Petráková, Vladimíra; Ashcheulov, Petr; Záliš, Stanislav; Nesladek, M.; Kraus, I.; Kratochvílová, Irena
2012-01-01
Roč. 209, č. 9 (2012), s. 1769-1773 ISSN 1862-6300 R&D Projects: GA TA ČR TA01011165; GA ČR(CZ) GAP304/10/1951 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z40400503 Keywords : defects * luminescence * nanodiamonds * surface termination Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.469, year: 2012 http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1862-6319/earlyview
Tudor DRUGAN
2003-08-01
Full Text Available The aim of the paper was to present the usefulness of the binomial distribution in studying of the contingency tables and the problems of approximation to normality of binomial distribution (the limits, advantages, and disadvantages. The classification of the medical keys parameters reported in medical literature and expressing them using the contingency table units based on their mathematical expressions restrict the discussion of the confidence intervals from 34 parameters to 9 mathematical expressions. The problem of obtaining different information starting with the computed confidence interval for a specified method, information like confidence intervals boundaries, percentages of the experimental errors, the standard deviation of the experimental errors and the deviation relative to significance level was solves through implementation in PHP programming language of original algorithms. The cases of expression, which contain two binomial variables, were separately treated. An original method of computing the confidence interval for the case of two-variable expression was proposed and implemented. The graphical representation of the expression of two binomial variables for which the variation domain of one of the variable depend on the other variable was a real problem because the most of the software used interpolation in graphical representation and the surface maps were quadratic instead of triangular. Based on an original algorithm, a module was implements in PHP in order to represent graphically the triangular surface plots. All the implementation described above was uses in computing the confidence intervals and estimating their performance for binomial distributions sample sizes and variable.
Fields, Laura [Fermilab; Genser, Krzysztof [Fermilab; Hatcher, Robert [Fermilab; Kelsey, Michael [SLAC; Perdue, Gabriel [Fermilab; Wenzel, Hans [Fermilab; Wright, Dennis H. [SLAC; Yarba, Julia [Fermilab
2017-08-21
Geant4 is the leading detector simulation toolkit used in high energy physics to design detectors and to optimize calibration and reconstruction software. It employs a set of carefully validated physics models to simulate interactions of particles with matter across a wide range of interaction energies. These models, especially the hadronic ones, rely largely on directly measured cross-sections and phenomenological predictions with physically motivated parameters estimated by theoretical calculation or measurement. Because these models are tuned to cover a very wide range of possible simulation tasks, they may not always be optimized for a given process or a given material. This raises several critical questions, e.g. how sensitive Geant4 predictions are to the variations of the model parameters, or what uncertainties are associated with a particular tune of a Geant4 physics model, or a group of models, or how to consistently derive guidance for Geant4 model development and improvement from a wide range of available experimental data. We have designed and implemented a comprehensive, modular, user-friendly software toolkit to study and address such questions. It allows one to easily modify parameters of one or several Geant4 physics models involved in the simulation, and to perform collective analysis of multiple variants of the resulting physics observables of interest and comparison against a variety of corresponding experimental data. Based on modern event-processing infrastructure software, the toolkit offers a variety of attractive features, e.g. flexible run-time configurable workflow, comprehensive bookkeeping, easy to expand collection of analytical components. Design, implementation technology, and key functionalities of the toolkit are presented and illustrated with results obtained with Geant4 key hadronic models.
Charpin, C.; Bonnefille, M.; Charrier, A.; Giorla, J.; Holstein, P.A.; Malinie, G.
2000-01-01
Our study is in line with the robustness of the LMJ target and the definition of safety margins. It is based on the determination of the 'acceptable gain', defined as 75% of the nominal gain. We have tested the sensitivity of the gain to physical and numerical parameters in the case of deteriorated implosions, i.e. when implosion conditions are not optimized. Moreover, we have simplified the radiative transport model, which enabled us to save a lot of computing time. All our calculations were done with the Lagrangian code FCI2 in a very simplified configuration. (authors)
Li, L.; Li, Z.; Li, K.; Blarel, L.; Wendisch, M.
2014-01-01
The polarized CIMEL sun/sky radiometers have been routinely operated within the Sun/sky-radiometer Observation NETwork (SONET) in China and some sites of the AErosol RObotic NETwork (AERONET) around the world. However, the polarization measurements are not yet widely used due to in a certain degree the lack of Stokes parameters derived directly from these polarization measurements. Meanwhile, it have been shown that retrievals of several microphysical properties of aerosol particles can be significantly improved by using degree of linear polarization (DoLP) measurements of polarized CIMEL sun/sky radiometers (CE318-DP). The Stokes parameters Q and U, as well as angle of polarization (AoP) contain additional information about linear polarization and its orientation. A method to calculate Stokes parameters Q, U, and AoP from CE318-DP polarized skylight measurements is introduced in this study. A new polarized almucantar geometry based on CE318-DP is measured to illustrate abundant variation features of these parameters. The polarization parameters calculated in this study are consistent with previous results of DoLP and I, and also comparable to vector radiative transfer simulations. - Highlights: • The CE318-DP polarized measurements are not yet widely used except DoLP. • Compared with DoLP and I, difficulty in calculating Stokes Q and U is discussed. • A new polarized almucantar observation geometry based on CE318-DP is executed. • We derive Stokes Q, U, and AoP both in principal and almucantar plane geometries. • The results are comparable with previous DoLP and I, as well as model simulations
Rivard, Mark J; Davis, Stephen D; DeWerd, Larry A; Rusch, Thomas W; Axelrod, Steve
2006-11-01
A new x-ray source, the model S700 Axxent X-Ray Source (Source), has been developed by Xoft Inc. for electronic brachytherapy. Unlike brachytherapy sources containing radionuclides, this Source may be turned on and off at will and may be operated at variable currents and voltages to change the dose rate and penetration properties. The in-water dosimetry parameters for this electronic brachytherapy source have been determined from measurements and calculations at 40, 45, and 50 kV settings. Monte Carlo simulations of radiation transport utilized the MCNP5 code and the EPDL97-based mcplib04 cross-section library. Inter-tube consistency was assessed for 20 different Sources, measured with a PTW 34013 ionization chamber. As the Source is intended to be used for a maximum of ten treatment fractions, tube stability was also assessed. Photon spectra were measured using a high-purity germanium (HPGe) detector, and calculated using MCNP. Parameters used in the two-dimensional (2D) brachytherapy dosimetry formalism were determined. While the Source was characterized as a point due to the small anode size, S700 Source exhibited depth dose behavior similar to low-energy photon-emitting low dose rate sources 125I and l03Pd, yet with capability for variable and much higher dose rates and subsequently adjustable penetration capabilities. This paper presents the calculated and measured in-water brachytherapy dosimetry parameters for the model S700 Source at the aforementioned three operating voltages.
Amin, E.; Hathout, A.M.; Shouman, S.
1997-01-01
The kyoto university reactor physics experiments on the university critical assembly is used to benchmark validate the NCNSRC calculations methodology. This methodology has two lines, diffusion and Monte Carlo. The diffusion line includes the codes WIMSD4 for cell calculations and the two dimensional diffusion code DIXY2 for core calculations. The transport line uses the MULTIKENO-Code vax Version. Analysis is performed for the criticality, and the temperature coefficients of reactivity (TCR) for the light water moderated and reflected cores, of the different cores utilized in the experiments. The results of both Eigen value and TCR approximately reproduced the experimental and theoretical Kyoto results. However, some conclusions are drawn about the adequacy of the standard wimsd4 library. This paper is an extension of the NCNSRC efforts to assess and validate computer tools and methods for both Et-R R-1 and Et-MMpr-2 research reactors. 7 figs., 1 tab
System of Modelling and Calculation Analysis of Neutron- Physical Experiments at Fast Reactors
Moiseyev, A.V.
2008-01-01
There is an actual task on storage, processing and analysis of the unique experimental data received on power fast reactors for their subsequent use in projects of fast reactors of new (4.) generation. For modeling and carrying out analysis of experiments the integrated computing system MODEXSYS has been developed. In this system the mechanism for consecutive calculation of a fast reactor states with the detailed description of its components is created. The system includes the database describing fast reactor states, results of neutron-physical characteristics measurements at fast reactor, calculation and benchmark models of experiments and calculation results. In system convenient search means and the special graphics shell are provided. It has Interfaces for processing of calculation results and their analysis. MODEXSYS system has been applied for analysis of three types of experiments at fast reactor: k eff , control rod worth and energy release distribution. The most important results of this analysis are described. Application of MODEXSYS system will raise accuracy and reliability of forecasting of fast reactors neutron-physical characteristics; for BN-600 reactor recommended level of accuracy is resulted. (authors)
System of Modelling and Calculation Analysis of Neutron- Physical Experiments at Fast Reactors
Moiseyev, A.V. [SSC RF - IPPE, 1 Bondarenko Square, Obninsk, Kaluga Region 249033 (Russian Federation)
2008-07-01
There is an actual task on storage, processing and analysis of the unique experimental data received on power fast reactors for their subsequent use in projects of fast reactors of new (4.) generation. For modeling and carrying out analysis of experiments the integrated computing system MODEXSYS has been developed. In this system the mechanism for consecutive calculation of a fast reactor states with the detailed description of its components is created. The system includes the database describing fast reactor states, results of neutron-physical characteristics measurements at fast reactor, calculation and benchmark models of experiments and calculation results. In system convenient search means and the special graphics shell are provided. It has Interfaces for processing of calculation results and their analysis. MODEXSYS system has been applied for analysis of three types of experiments at fast reactor: k{sub eff}, control rod worth and energy release distribution. The most important results of this analysis are described. Application of MODEXSYS system will raise accuracy and reliability of forecasting of fast reactors neutron-physical characteristics; for BN-600 reactor recommended level of accuracy is resulted. (authors)
Calculation of LWR kinetic parameter βeff. validation on the mistral experiments
Santamarina, Alain; Erradi, Lahoussine
2011-01-01
This work presents the analysis of the MISTRAL experiments on the determination of the effective delayed neutron fraction β eff for UOX and MOX Light Water Reactor cores using the APOLLO2.8 code and JEFF-3.1.1 nuclear data library. The objective is to check if the new 8 time groups data in JEFF3 library (instead of the classical 6 groups) allows reducing the Calculation - Experiment discrepancy observed when using ENDF/B-VII or the previous JEF-2 library. Our analysis has shown that the C/E bias is reduced from +2.8% to +0.8% ± 1.6% for the UOX cores and from +0.8% to +0.2% ± 1.6% for the MOX cores. (author)
Toporova, V.G.; Pimenov, V.V.
2004-01-01
Full text: Reactor material science is one of the main scientific directions of the RIAR activities. Particularly, a wide range of materials and products testing under irradiation is performed in reactor facility SM (RF SM). To solve the tasks specified in the technical specification for an experiment, previously, the test conditions are chosen. At the minimum a space-energy distribution of neutrons and heating rate in the materials under test are important as well as temperature conditions of irradiation. The up-to-date software and libraries of nuclear data allow modeling of neutron-material interaction processes to a considerable degree of details and also obtaining a true neutron distribution by calculation methods. As a result of a great scope of work on verification, a calculation model, developed on the basis of a package of applied software MCU (option MCU-4/SM22) and analogue Monte-Carlo method, is widely used at RIAR. The MCU geometric module makes it possible to model the SM core and reflector in three-dimensional geometry with sufficient accuracy and to describe all elements of the channel structure and irradiation device with specimens. The calculation model of RF SM is tested using the results of activation experiments performed in its critical assembly, geometric parameters and structural materials of which correspond completely with the prototype. The difference in the calculated and experimental values is less than 2.5%. Possibilities of the calculated estimation of operating temperature conditions of absorbing elements under irradiation should be considered separately. As the conducted calculations and their analysis show, to define the fuel column temperature correctly, one needs reliable data on thermal-physical parameters of materials, especially ceramic ones, such as titanium, dysprosium or boron carbide. This is very important for boron carbide-absorbing elements for actually all their operation parameters (such as: gas release, swelling
Abo-Elmagd, M.; Mansy, M.; Eissa, H.M.; El-Fiki, M.A.
2006-01-01
The equilibrium factor F between radon and its daughters as a function of the track density ratio D/D 0 between bare and in can track detectors is solved graphically and gave more accurate solution than that solved mathematically elsewhere. The advantages of the graphical solution come from its simplicity and does not need any tedious mathematical formula or a computer program. The simplicity of this solution makes us study many parameters that affect the equilibrium factor determination such as the detector type, the diffusion chamber dimensions, the membrane specifications and the behavior of α-emitters around the detector. The results show that the equilibrium factor as a function of D/D 0 takes different form according to the facility used. The range of this study covers two widely used detectors (CR-39 and LR-115) equipped in two widely used diffusion chambers (small and medium chambers)
Calculation of proton-deuteron phase parameters including the Coulomb force
Alt, E.O.; Sandhas, W.; Ziegelmann, H.
1985-04-01
A previously proposed exact method for including the Coulomb force in three-body collisions is applied to proton-deuteron scattering. We present phase shifts for angular momenta up to L=9, from elastic threshold to 50 MeV proton laboratory energy. Separable rank-one potentials are taken for the nuclear interactions. A charge-independent and a charge-symmetric choise, while leading to different neutron-deuteron and proton-deuteron phase parameters, nevertheless yields practically the same Coulomb corrections. We, moreover, investigate the question of P-wave resonances.A critical comparison of our results with those obtained in a co-ordinate space formalism is performed. Furthermore, proposals for an approximate inclusion of the Coulomb potential are tested, and found unsatisfactory. (orig.)
Avrigeanu, M.; Avrigeanu, V.
1992-02-01
A systematic study on effects of statistical model parameters and semi-classical pre-equilibrium emission models has been carried out for the (n,p) reactions on the 56 Fe and 60 Co target nuclei. The results obtained by using various assumptions within a given pre-equilibrium emission model differ among them more than the ones of different models used under similar conditions. The necessity of using realistic level density formulas is emphasized especially in connection with pre-equilibrium emission models (i.e. with the exciton state density expression), while a basic support could be found only by replacement of the Williams exciton state density formula with a realistic one. (author). 46 refs, 12 figs, 3 tabs
A spatial track formation model and its use for calculating etch-pit parameters of light nuclei
Somogyi, G.; Scherzer, R.; Grabisch, K.; Enge, W.
1976-01-01
A generalized geometrical model of etch-pit formation in three dimensions is presented for nuclear particles entering isotropic solids at arbitrary angles of incidence. With this model one can calculate the relations between any particle parameter /Z = charge, M = mass, R = range, theta = angle of incidence/ and etching or track parameter /h = removed detector layer, L = track length, d = track diameter, etch-pit profile and contour/ for track etching rates varying monotonically along the trajectory of particles. Using a computer algorithm, calculations have been performed to study identification problems of nuclei of Z = 1-8 registered in a stack of polycarbonate sheets. For these calculations the etching rate ratio vs residual range curves were parametrized with a form of V -1 (R) = 1-Σasub(i) exp (- bsub(i)R) which does not involve the existence of a threshold for track registration. Particular attention was paid to the study of the evolution of etch-pit sizes for relatively high values of h. For this case, data are presented for the charge and isotope resolving power of the identification methods based on the relations L(R) of d(R). Calculations were also made to show the effect of the relative /parallel and opposite/ orientations between the directions of track etching and particle speed on etch-pit evolution. These studies offered new identification methods based on the determination of the curves L(parallel) vs L(opposite) and d(parallel) vs d(opposite), respectively. (orig.) [de
Physical property parameter set for modeling ICPP aqueous wastes with ASPEN electrolyte NRTL model
Schindler, R.E.
1996-09-01
The aqueous waste evaporators at the Idaho Chemical Processing Plant (ICPP) are being modeled using ASPEN software. The ASPEN software calculates chemical and vapor-liquid equilibria with activity coefficients calculated using the electrolyte Non-Random Two Liquid (NRTL) model for local excess Gibbs free energies of interactions between ions and molecules in solution. The use of the electrolyte NRTL model requires the determination of empirical parameters for the excess Gibbs free energies of the interactions between species in solution. This report covers the development of a set parameters, from literature data, for the use of the electrolyte NRTL model with the major solutes in the ICPP aqueous wastes
Lee, Seung Min
2009-01-01
This work presents a theoretical study of reactor kinetics focusing on the methodology of calculation and the experimental measurements of the so-called kinetic parameters. A comparison between the methodology based on the Dulla's formalism and the classical method is made. The objective is to exhibit the dependence of the parameters on subcriticality level and perturbation. Two different slab type systems were considered: thermal one and fast one, both with homogeneous media. One group diffusion model was used for the fast reactor, and for the thermal system, two groups diffusion model, considering, in both case, only one precursor's family. The solutions were obtained using the expansion method. Also, descriptions of the main experimental methods of measurements of the kinetic parameters are presented in order to put a question about the compatibility of these methods in subcritical region. (author)
Markova, N.; Puls, J.; Langer, N.
2018-05-01
Context. Massive stars play a key role in the evolution of galaxies and our Universe. Aims: Our goal is to compare observed and predicted properties of single Galactic O stars to identify and constrain uncertain physical parameters and processes in stellar evolution and atmosphere models. Methods: We used a sample of 53 objects of all luminosity classes and with spectral types from O3 to O9.7. For 30 of these, we determined the main photospheric and wind parameters, including projected rotational rates accounting for macroturbulence, and He and N surface abundances, using optical spectroscopy and applying the model atmosphere code FASTWIND. For the remaining objects, similar data from the literature, based on analyses by means of the CMFGEN code, were used instead. The properties of our sample were then compared to published predictions based on two grids of single massive star evolution models that include rotationally induced mixing. Results: Any of the considered model grids face problem in simultaneously reproducing the stellar masses, equatorial gravities, surface abundances, and rotation rates of our sample stars. The spectroscopic masses derived for objects below 30 M⊙ tend to be smaller than the evolutionary ones, no matter which of the two grids have been used as a reference. While this result may indicate the need to improve the model atmosphere calculations (e.g. regarding the treatment of turbulent pressure), our analysis shows that the established mass problem cannot be fully explained in terms of inaccurate parameters obtained by quantitative spectroscopy or inadequate model values of Vrot on the zero age main sequence. Within each luminosity class, we find a close correlation of N surface abundance and luminosity, and a stronger N enrichment in more massive and evolved O stars. Additionally, we also find a correlation of the surface nitrogen and helium abundances. The large number of nitrogen-enriched stars above 30 M⊙ argues for rotationally
Fabíola Maria Sabino Meireles
2013-03-01
Full Text Available Objective: To characterize the main strategies and parameters used by physical therapists in difficult mechanical ventilation weaning. Methods: Cross-sectional study including all the physical therapists working in adult Intensive Care Units in three public hospitals in Fortaleza-CE. A questionnaire with closed questions related to difficult mechanical ventilation weaning was applied, with either one or multiple answers. The data was treated with descriptive and non-parametric analysis. Results: Among the parameters mostly used by the 56 interviewed physical therapists for the difficult weaning, were found: current volume reduction (26 - 46.4% and desaturation during aspiration (17 - 30.4%. It was observed that 38 (67.9% alternate T-tube and continuous positive airway pressure (CPAP as strategies for difficult weaning, and 28 (50% reported reducing the pressure support. There was no statistical difference between the strategies used in the studied hospitals, neither correlation between strategies and parameters. Conclusion: It was found that physical therapists have been performing similar strategies, which are also shown in the literature, but this is not the case with the parameters. The parameters used are not supported by the literature.
Sensitivity analysis of physical/operational parameters in neutron multiplicity counting
Peerani, P.; Marin Ferrer, M.
2007-01-01
In this paper, we perform a sensitivity study on the influence of various physical and operational parameters on the results of neutron multiplicity counting. The purpose is to have a better understanding of the importance of each component and its contribution to the measurement uncertainty. Then we will be able to determine the optimal conditions for the operational parameters and for detector design and as well to point out weaknesses in the knowledge of critical fundamental nuclear data
Effect of parameter calculation in direct estimation of the Lyapunov exponent in short time series
A. M. López Jiménez
2002-01-01
Full Text Available The literature about non-linear dynamics offers a few recommendations, which sometimes are divergent, about the criteria to be used in order to select the optimal calculus parameters in the estimation of Lyapunov exponents by direct methods. These few recommendations are circumscribed to the analysis of chaotic systems. We have found no recommendation for the estimation of λ starting from the time series of classic systems. The reason for this is the interest in distinguishing variability due to a chaotic behavior of determinist dynamic systems of variability caused by white noise or linear stochastic processes, and less in the identification of non-linear terms from the analysis of time series. In this study we have centered in the dependence of the Lyapunov exponent, obtained by means of direct estimation, of the initial distance and the time evolution. We have used generated series of chaotic systems and generated series of classic systems with varying complexity. To generate the series we have used the logistic map.
Recommended environmental dose calculation methods and Hanford-specific parameters. Revision 2
Schreckhise, R.G.; Rhoads, K.; Napier, B.A.; Ramsdell, J.V. [Pacific Northwest Lab., Richland, WA (United States); Davis, J.S. [Westinghouse Hanford Co., Richland, WA (United States)
1993-03-01
This document was developed to support the Hanford Environmental Dose overview Panel (HEDOP). The Panel is responsible for reviewing all assessments of potential doses received by humans and other biota resulting from the actual or possible environmental releases of radioactive and other hazardous materials from facilities and/or operations belonging to the US Department of Energy on the Hanford Site in south-central Washington. This document serves as a guide to be used for developing estimates of potential radiation doses, or other measures of risk or health impacts, to people and other biota in the environs on and around the Hanford Site. It provides information to develop technically sound estimates of exposure (i.e., potential or actual) to humans or other biotic receptors that could result from the environmental transport of potentially harmful materials that have been, or could be, released from Hanford operations or facilities. Parameter values and information that are specific to the Hanford environs as well as other supporting material are included in this document.
Physics-based Inverse Problem to Deduce Marine Atmospheric Boundary Layer Parameters
2017-03-07
knowledge and capabilities in the use and development of inverse problem techniques to deduce atmospheric parameters. WORK COMPLETED The research completed...please find the Final Technical Report with SF 298 for Dr. Erin E. Hackett’s ONR grant entitled Physics -based Inverse Problem to Deduce Marine...From- To) 07/03/2017 Final Technica l Dec 2012- Dec 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Physics -based Inverse Problem to Deduce Marine
HCP track calculations in Lif:Mg,Ti: 3D modeling of the ''track – escape'' parameter
Sattinger, D.; Sharon, A.; Horowitz, Y.S.
2011-01-01
The conceptual framework of the track interaction model (TIM) was conceived in the 1970s and mathematically formulated in the 1980s to describe heavy charged particle TL fluence response supralinearity. The extended track interaction model (ETIM) was developed to include saturation effects due to overlapping tracks and has been applied to both proton and alpha particle TL fluence response. One of the parameters of major importance in the TIM is the ''track – escape'' parameter, defined by N e /N w , where N e represents the number of electrons which escape the parent track during heating, and N w is the number of electrons which recombine within the parent track to produce a TL photon. Recently a first attempt was carried out to theoretically model escape parameters calculated in 2D geometry as a function of particle type and energy using trapping center (TC), luminescent center (LC) and competitive center (CC) occupation probabilities calculated from track segment radial dose distributions and optical absorption (OA) dose response. In this study, the calculations are extended to 3D geometry using a Monte Carlo approach which samples the point of creation of the charge carriers according to the TC occupation probabilities and then estimates N w by sampling the chord length to the track exterior. Charge carriers which escape the irradiated track volume contribute to N e . This more sophisticated 3D calculation of N e /N w is expected to increase the reliability of the modeling of heavy charged particle TL fluence response in the framework of the ETIM and enhance our understanding of “track effects” in Heavy Charged Particle (HCP) induced TL.
Garger, Evgenii K; Meisenberg, Oliver; Odintsov, Oleksiy; Shynkarenko, Viktor; Tschiersch, Jochen
2013-10-15
Nuclear fuel particles of Chernobyl origin are carriers of increased radioactivity (hot particles) and are still present in the atmosphere of the Chernobyl exclusion zone. Workers in the zone may inhale these particles, which makes assessment necessary. The residence time in the lungs and the transfer in the blood of the inhaled radionuclides are crucial for inhalation dose assessment. Therefore, the dissolution of several kinds of nuclear fuel particles from air filters sampled in the Chernobyl exclusion zone was studied. For this purpose filter fragments with hot particles were submersed in simulated lung fluids (SLFs). The activities of the radionuclides (137)Cs, (90)Sr, (239+240)Pu and (241)Am were measured in the SLF and in the residuum of the fragments by radiometric methods after chemical treatment. Soluble fractions as well as dissolution rates of the nuclides were determined. The influence of the genesis of the hot particles, represented by the (137)Cs/(239+240)Pu ratio, on the availability of (137)Cs was demonstrated, whereas the dissolution of (90)Sr, (239+240)Pu and (241)Am proved to be independent of genesis. No difference in the dissolution of (137)Cs and (239+240)Pu was observed for the two applied types of SLF. Increased solubility was found for smaller hot particles. A two-component exponential model was used to describe the dissolution of the nuclides as a function of time. The results were applied for determining individual inhalation dose coefficients for the workers at the Chernobyl construction site. Greater dose coefficients for the respiratory tract and smaller coefficients for the other organs were calculated (compared to ICRP default values). The effective doses were in general lower for the considered radionuclides, for (241)Am even by one order of magnitude. © 2013 Elsevier B.V. All rights reserved.
Elmahroug, Y.; Tellili, B.; Souga, C.; Manai, K.
2015-01-01
Highlights: • Description of the theoretical method used by the ParShield program. • Description of the ParShield program. • Test and validation the ParShield program. - Abstract: This study aims to present a new computer program called ParShield which determines the neutron and gamma-ray shielding parameters. This program can calculate the total mass attenuation coefficients (μ t ), the effective atomic numbers (Z eff ) and the effective electron densities (N eff ) for gamma rays and it can also calculate the effective removal cross-sections (Σ R ) for fast neutrons for mixtures and compounds. The results obtained for the gamma rays by using ParShield were compared with the results calculated by the WinXcom program and the measured results. The obtained values of (Σ R ) were tested by comparing them with the measured results,the manually calculated results and with the results obtained by using MERCSFN program and an excellent agreement was found between them. The ParShield program can be used as a fast and effective tool to choose and compare the shielding materials, especially for the determination of (Z eff ) and (N eff ), there is no other programs in the literature which can calculate
Moret-Fernández, D.; Latorre, B.
2017-01-01
The water retention curve (θ(h)), which defines the relationship between the volumetric water content (θ) and the matric potential (h), is of paramount importance to characterize the hydraulic behaviour of soils. Because current methods to estimate θ(h) are, in general, tedious and time consuming, alternative procedures to determine θ(h) are needed. Using an upward infiltration curve, the main objective of this work is to present a method to determine the parameters of the van Genuchten (1980) water retention curve (α and n) from the sorptivity (S) and the β parameter defined in the 1D infiltration equation proposed by Haverkamp et al. (1994). The first specific objective is to present an equation, based on the Haverkamp et al. (1994) analysis, which allows describing an upward infiltration process. Secondary, assuming a known saturated hydraulic conductivity, Ks, calculated on a finite soil column by the Darcy's law, a numerical procedure to calculate S and β by the inverse analysis of an exfiltration curve is presented. Finally, the α and n values are numerically calculated from Ks, S and β. To accomplish the first specific objective, cumulative upward infiltration curves simulated with HYDRUS-1D for sand, loam, silt and clay soils were compared to those calculated with the proposed equation, after applying the corresponding β and S calculated from the theoretical Ks, α and n. The same curves were used to: (i) study the influence of the exfiltration time on S and β estimations, (ii) evaluate the limits of the inverse analysis, and (iii) validate the feasibility of the method to estimate α and n. Next, the θ(h) parameters estimated with the numerical method on experimental soils were compared to those obtained with pressure cells. The results showed that the upward infiltration curve could be correctly described by the modified Haverkamp et al. (1994) equation. While S was only affected by early-time exfiltration data, the β parameter had a
Lessard, E.T.; Skrable, K.W.
1981-01-01
Two dosimetric models, the catenary compartmental model (Be70) and the slug flow model (Sk75), are examined using three sets of physiological parameters: those proposed by Eve, those proposed by ICRP, and those obtained from the Textbook of Physiology and Biochemistry by Bell et al. The impact of physiological parameters on the dosimetry of the tract is illustrated by comparing calculated maximum permissible daily activity ingestion rates for single, unabsorbed, particle emitting radionuclides with an effective energy term of unity. The conclusions drawn from this intercomparison of six different cases are: Current dosimetric models which use physiological parameters described in this article do not significantly disagree, and for the determination of average dose equivalent rates to segments of the tract due to chronic, long term ingestion of any radionuclide, the catenary compartmental model is a mathematically simpler approach. The catenary model in addition has certain advantages for the calculation of the photon dose contribution to one segment from cumulated activity (disintegrations) in another segment
Myron W. Kelly
1977-01-01
The pertinent literature has been reviewed, and the apparent effects of selected processing parameters on the resultant particleboard properties, as generally reported in the literature, have been determined. Resin efficiency, type and level, furnish, and pressing conditions are reviewed for their reported effects on physical, strength, and moisture and dimensional...
Fast neutron reactor noise analysis: beginning failure detection and physical parameter estimation
Le Guillou, G.
1975-01-01
The analysis of the signals fluctuations coming from a power nuclear reactor (a breeder), by correlation methods and spectral analysis has two principal applications: on line estimation of physical parameters (reactivity coefficients); beginning failures (little boiling, abnormal mechanic vibrations). These two applications give important informations to the reactor core control and permit a good diagnosis [fr
Marching on in anything: solving electromagnetic field equations with a varying physical parameter
Tijhuis, A.G.; Zwamborn, A.P.M.; Smith, P.D.; Cloude, S.R.
2002-01-01
In this paper, we consider the determination of electromagnetic fields for a (large) number of values of a physical parameter. We restrict ourselves to the case where the linear system originates from one or more integral equations. We apply an iterative procedure based on the minimization of an
Physical Parameters of the Overcontact Binary AH Cnc in the Old Open Cluster M 67
Yakut, K.; Aerts, C.C.
2006-01-01
We present a photometric study of the overcontact binary AH Cnc. The CCD observations were done with the Russian-Turkish 1.5 m telescope and the light-curve was solved with the Wilson-Devinney code. The physical parameters of the components have been deduced as M_{1} = 1.22 Msun,
NONE
2003-07-01
These scientific days had for objective to draw up the situation of calculation codes of radiation transport, of sources estimation, of radiation doses managements and to draw the future perspectives. (N.C.)
A co-ordinate system for reactor physics calculations in hexagonal geometry
Burte, D.P.
1990-01-01
A method for generating all the geometric information concerning typical reactor physics calculations for a basically hexagonal reactor core or its sector involving any of the possible symmetries is presented. The geometrically allowed symmetries for regular hexagons are discussed. The approach is based on the choice of a suitable co-ordinate system, viz. one using three coplanar (including one redundant) axes, each at 120 0 with its cyclically preceding one. A code named KEKULE' is developed for a 2-D, finite difference, one-group diffusion analysis of a hexagonal core using the approach. It can cater to a full hexagonal core as well as to any symmetric sectorial part of it. The main feature of the code is that the input concerning geometry is a bare minimum. It is hoped that the approach presented will be useful even for the calculations for hexagonal fuel assemblies. (author)
Assessment of uncertainty in full core reactor physics calculations using statistical methods
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)
Assessment of uncertainty in full core reactor physics calculations using statistical methods
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)
Methods for reactor physics calculations for control rods in fast reactors
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
Rivard, Mark J.; Davis, Stephen D.; DeWerd, Larry A.; Rusch, Thomas W.; Axelrod, Steve
2006-01-01
A new x-ray source, the model S700 Axxent trade mark sign X-Ray Source (Source), has been developed by Xoft Inc. for electronic brachytherapy. Unlike brachytherapy sources containing radionuclides, this Source may be turned on and off at will and may be operated at variable currents and voltages to change the dose rate and penetration properties. The in-water dosimetry parameters for this electronic brachytherapy source have been determined from measurements and calculations at 40, 45, and 50 kV settings. Monte Carlo simulations of radiation transport utilized the MCNP5 code and the EPDL97-based mcplib04 cross-section library. Inter-tube consistency was assessed for 20 different Sources, measured with a PTW 34013 ionization chamber. As the Source is intended to be used for a maximum of ten treatment fractions, tube stability was also assessed. Photon spectra were measured using a high-purity germanium (HPGe) detector, and calculated using MCNP. Parameters used in the two-dimensional (2D) brachytherapy dosimetry formalism were determined. While the Source was characterized as a point due to the small anode size, P (5) were 0.20, 0.24, and 0.29 for the 40, 45, and 50 kV voltage settings, respectively. For 1 125 I and 103 Pd, yet with capability for variable and much higher dose rates and subsequently adjustable penetration capabilities. This paper presents the calculated and measured in-water brachytherapy dosimetry parameters for the model S700 Source at the aforementioned three operating voltages
The Hypertrophic Marchigiana: physical and biochemical parameters for meat quality evaluation
F. M. Sarti
2010-04-01
Full Text Available The aim of this study was to evaluate the meat quality of double muscled Marchigiana young bulls characterized by different genotypes for the hypertrophy: normal and mutated (heterozygous. Calpain and calpastatin activities were determined to verify the state of aging meat on a sample of Longissimus thoracis muscle (XIII thoracic rib taken at slaughtering (0h and after 24 hours (24h. After 14 days of aging, another sample of muscle was taken to evaluate physical and chemical parameters of meat quality. The results showed a better meat quality of mutated animals respect normal animals. Another interesting result was the correlation between the biochemical parameters and some physical parameters, such as WBS (Warner Bratzler Shear Force, CL (Cooking loss. These results showed the relationship between the proteolytic activity of calpain system and meat tenderness.
Matei, Iulia; Ionescu, Sorana; Hillebrand, Mihaela
2011-01-01
The interaction between fisetin, an antioxidant and neuroprotective flavonoid, and human serum albumin (HSA) is investigated by means of fluorescence (steady-state, synchronous, time-resolved) and circular dichroism (CD) spectroscopy. The formation of a 1:1 complex with a constant of about 10 5 M -1 was evidenced. Foerster's resonance energy transfer and competitive binding with site markers warfarin and ibuprofen were considered and discussed. Changes in the CD band of HSA indicate a decrease in the α-helix content upon binding. An induced CD signal for bound fisetin was observed and rationalized in terms of density functional theory calculations. - Highlights: → Fisetin-BSA system was studied by fluorescence spectroscopy. → Binding parameters, association constant and number of sites were estimated. → Binding site of fisetin was identified by competitive experiments. → Conformational changes in HSA and fisetin were evidenced by circular dichroism. → TDDFT calculated CD spectra supported the experimental data.
Matei, Iulia; Ionescu, Sorana [Department of Physical Chemistry, Faculty of Chemistry, University of Bucharest, Bd. Regina Elisabeta 4-12, 030018 Bucharest (Romania); Hillebrand, Mihaela, E-mail: mihh@gw-chimie.math.unibuc.ro [Department of Physical Chemistry, Faculty of Chemistry, University of Bucharest, Bd. Regina Elisabeta 4-12, 030018 Bucharest (Romania)
2011-08-15
The interaction between fisetin, an antioxidant and neuroprotective flavonoid, and human serum albumin (HSA) is investigated by means of fluorescence (steady-state, synchronous, time-resolved) and circular dichroism (CD) spectroscopy. The formation of a 1:1 complex with a constant of about 10{sup 5} M{sup -1} was evidenced. Foerster's resonance energy transfer and competitive binding with site markers warfarin and ibuprofen were considered and discussed. Changes in the CD band of HSA indicate a decrease in the {alpha}-helix content upon binding. An induced CD signal for bound fisetin was observed and rationalized in terms of density functional theory calculations. - Highlights: > Fisetin-BSA system was studied by fluorescence spectroscopy. > Binding parameters, association constant and number of sites were estimated. > Binding site of fisetin was identified by competitive experiments. > Conformational changes in HSA and fisetin were evidenced by circular dichroism. > TDDFT calculated CD spectra supported the experimental data.
Bratoljic, T.; Bischof, H.; Lorenzen, H.W.
1988-01-01
The generator, with its concentric and in part solid and conductive parts, is represented by a shell model, and the parameters of the system of equivalent windings are first obtained approximately using a two-dimensional analytical field calculation. The effect of the finite length, which is neglected in this field calculation, is taken into account by variation of the model geometry and material conductivity so that the Nyquist plots of the model impedances are optimally matched to those of the real system. The resulting machine model is checked and confirmed by comparing the simulation results with test measurements. It is further shown that an outer damper cylinder which is free to rotate independently provides significant mechanical relief of the shaft line during transient processes
Maciel, A.K.A.
1977-03-01
The electronic structure of the interstitial hydrogen atom in KF, NaCl, KCl, and RbCl cristals has been studied using the self-consistent-field multiple-scattering Xα method. In the present calculation a cluster constituted by the hydrogen atom surrounded by its first anion and cation neighbors in a cubic shell has been used. The optical transition energies and hyperfine contact parameters with the interstitial proton and the first shell nuclei have been evaluated. The agreement obtained with the experimental data and the relative independence of the method under variations of its intrinsic parameters, indicate that this method can be adequate to the study of defects in ionic cristals. (author) [pt
Kim, Seung Jun [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Buechler, Cynthia Eileen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-07-17
The current study aims to predict the steady state power of a generic solution vessel and to develop a corresponding heat transfer coefficient correlation for a Moly99 production facility by conducting a fully coupled multi-physics simulation. A prediction of steady state power for the current application is inherently interconnected between thermal hydraulic characteristics (i.e. Multiphase computational fluid dynamics solved by ANSYS-Fluent 17.2) and the corresponding neutronic behavior (i.e. particle transport solved by MCNP6.2) in the solution vessel. Thus, the development of a coupling methodology is vital to understand the system behavior at a variety of system design and postulated operating scenarios. In this study, we report on the k-effective (keff) calculation for the baseline solution vessel configuration with a selected solution concentration using MCNP K-code modeling. The associated correlation of thermal properties (e.g. density, viscosity, thermal conductivity, specific heat) at the selected solution concentration are developed based on existing experimental measurements in the open literature. The numerical coupling methodology between multiphase CFD and MCNP is successfully demonstrated, and the detailed coupling procedure is documented. In addition, improved coupling methods capturing realistic physics in the solution vessel thermal-neutronic dynamics are proposed and tested further (i.e. dynamic height adjustment, mull-cell approach). As a key outcome of the current study, a multi-physics coupling methodology between MCFD and MCNP is demonstrated and tested for four different operating conditions. Those different operating conditions are determined based on the neutron source strength at a fixed geometry condition. The steady state powers for the generic solution vessel at various operating conditions are reported, and a generalized correlation of the heat transfer coefficient for the current application is discussed. The assessment of multi-physics
Mandlik, Nandkumar, E-mail: ntmandlik@gmail.com [Department of Physics, University of Pune, Ganeshkhind, Pune -411007, India and Department of Physics, Fergusson College, Pune- 411004 (India); Patil, B. J.; Bhoraskar, V. N.; Dhole, S. D. [Department of Physics, University of Pune, Ganeshkhind, Pune -411007 (India); Sahare, P. D. [Department of Physics and Astrophysics, University of Delhi, Delhi- 110007 (India)
2014-04-24
Nanorods of CaSO{sub 4}: Dy having diameter 20 nm and length 200 nm have been synthesized by the chemical coprecipitation method. These samples were irradiated with gamma radiation for the dose varying from 0.1 Gy to 50 kGy and their TL characteristics have been studied. TL dose response shows a linear behavior up to 5 kGy and further saturates with increase in the dose. A Computerized Glow Curve Deconvolution (CGCD) program was used for the analysis of TL glow curves. Trapping parameters for various peaks have been calculated by using CGCD program.
Cabezas, R.; Lubian, J.; Moreno, E.
1992-01-01
In this paper scattering of neutron in medium mass nuclei (48 < a < 64) at low energies (1-5 Mev) is analyzed. The Hauser-Feshbach-Moldauer formalism and the coupled channel method is used in a combined way. In both cases, the deformed optical potential in the frame of the harmonic vibrational models is considered of integral and total cross section and angular distribution enphasized. It's shown that the use of different set parameters has a mose influence at low energies and represented a contribution of 10% of the calculated cross section with the same potential
Schmidtlein, P.
1980-01-01
The evaluation of the influences of the examined parameters on the calculation of the dose rate shows that a new concept for determination of the radiation exposure in the surroundings of nuclear facilities is required. A computing formalism based on theoretical considerations determines the effective activity absorbed and, after combination with dose rate factors, the effective dose rate per year. It is of great importance to verify the validity of the still incomplete input data for determination of the dose factors of the age groups 'infants' and 'children' and to prepare new data records. (DG) [de
Horas, Jorge A; Olguin, Osvaldo R; Rizzotto, Marcos G
2005-01-01
We model the heterogeneous response to radiation of multicellular tumour spheroids assuming position- and volume-dependent radiosensitivity. We propose a method to calculate the overall radiosensitivity parameters to obtain the surviving fraction of tumours. A mathematical model of a spherical tumour with a hypoxic core and a viable rim which is a caricature of a real tumour is constructed. The model is embedded in a two-compartment linear-quadratic (LQ) model, assuming a mixed bivariated Gaussian distribution to attain the radiosensitivity parameters. Ergodicity, i.e., the equivalence between ensemble and volumetric averages is used to obtain the overall radiosensitivities for the two compartments. We obtain expressions for the overall radiosensitivity parameters resulting from the use of both a linear and a nonlinear dependence of the local radiosensitivity with position. The model's results are compared with experimental data of surviving fraction (SF) for multicellular spheroids of different sizes. We make one fit using only the smallest spheroid data and we are able to predict the SF for the larger spheroids. These predictions are acceptable particularly using bounded sensitivities. We conclude with the importance of taking into account the contribution of clonogenic hypoxic cells to radiosensitivity and with the convenience of using bounded local sensitivities to predict overall radiosensitivity parameters
A. KH. Alassafee
2017-11-01
Full Text Available The modified DebyeâEinstein approximation model is used to calculate nanoscale size-dependent values of Gruneisen parameters and lattice specific heat capacity for Si nanowires. All parameters forming the model, including Debye temperatures, bulk moduli, the lattice thermal expansion and the lattice volume, are calculated according to their nanoscale size dependence. Values for lattice volume Gruneisen parameters increase with the decrease of the nanowiresâ diameter, while all other parameters decrease. The nanosize dependence of lattice thermal parameters agree with other reported theoretical results. Keywords: Lattice specific heat capacity, Gruneisen parameter, DebyeâEinstein model, Si nanowires
Devin W McBride
Full Text Available The activity coefficient is largely considered an empirical parameter that was traditionally introduced to correct the non-ideality observed in thermodynamic systems such as osmotic pressure. Here, the activity coefficient of free-solvent is related to physically realistic parameters and a mathematical expression is developed to directly predict the activity coefficients of free-solvent, for aqueous protein solutions up to near-saturation concentrations. The model is based on the free-solvent model, which has previously been shown to provide excellent prediction of the osmotic pressure of concentrated and crowded globular proteins in aqueous solutions up to near-saturation concentrations. Thus, this model uses only the independently determined, physically realizable quantities: mole fraction, solvent accessible surface area, and ion binding, in its prediction. Predictions are presented for the activity coefficients of free-solvent for near-saturated protein solutions containing either bovine serum albumin or hemoglobin. As a verification step, the predictability of the model for the activity coefficient of sucrose solutions was evaluated. The predicted activity coefficients of free-solvent are compared to the calculated activity coefficients of free-solvent based on osmotic pressure data. It is observed that the predicted activity coefficients are increasingly dependent on the solute-solvent parameters as the protein concentration increases to near-saturation concentrations.
Borio, A.; Cagnazzo, M.; Marchetti, F.; Pappalardo, P.; Salvini, A.
2004-01-01
The aim of this work is to determine moderating properties of different materials (water, graphite, perfluoropolyethers), in particular the slowing down power (SDP) and the moderating ratio (MR), defined as SDP =ξΣ S and MR=ξΣ S /Σ A , where Σ S and Σ A represent the macroscopic scattering and absorption cross section, respectively, and ξ is the average logarithmic energy loss per collision. Slowing-down power indicates how rapidly a neutron will slow down in the material, but it does not fully explain the effectiveness of the material as a moderator. In fact, a material can slow down neutrons with high efficiency because of its big Σ S , but it can be a poor moderator because with high probability it also absorbs neutrons. Thus, the most complete measure of the effectiveness of a moderator is the moderating ratio parameter which takes into account also the absorption effects: the bigger is the moderating ratio values, the more effectively the material performs as a moderator. The first part of the work consisted in the comparison between the SDP and MR parameter evaluated for different materials by means of Monte Carlo simulations and by means of calculations based on their definition formula (they are developed from knowledge of material composition and of microscopic cross section σ i (derived from literature)). It was found that this comparison showed a good agreement with errors less than 10 %. Thus the Monte Carlo code seems to be a good support for the calculation of the moderating parameters, particularly useful when the materials are compounds of many elements. The second part of the work was dedicated to correlate the materials' MR values with the measured variation of reactivity induced by the insertion of the materials in the core of TRIGA Mark II reactor of the University of Pavia. This is possible by definition of a new parameter for the measure. This parameter, named S, depends on the total weight of the sample inserted in the reactor core
Kim, Jiwoong; Kang, Shinhoo
2012-01-01
Highlights: ► Elastic properties of TiC, TiN and their alloys were calculated by ab initio calculations. ► Debye temperature and Gruneisen constant of TiC, TiN and their alloys were calculated as a function of nitrogen content. ► Thermo-physical properties were calculated as a function of nitrogen content. ► Thermal expansion of the alloys was fitted in different temperature range. - Abstract: The equilibrium lattice parameters, elastic properties, material brittleness, heat capacities, and thermal expansion coefficients of TiC, TiN, and their intermediate composition alloys (Ti(C 1−x N x ), x = 0.25, 0.5, and 0.75) were calculated using ab initio density functional theory (DFT) methods. We employed the Debye–Gruneisen model to calculate a finite temperature heat capacity and thermal expansion coefficient. The calculated elastic moduli and thermal expansion coefficients agreed well with the experimental data and with other DFT calculations. Accurate heat capacities of TiC, TiN, and their intermediate composition alloys were obtained by calculating not only the phonon contributions but also the electron contributions to the heat capacity. Our calculations indicated that the heat capacity differences between each composition originated mainly from the electronic contributions.
Bouveret, F
2001-07-01
Although Boiling Water Reactors generate a quarter of worldwide nuclear electricity, they have been only little studied in France. A certain interest now shows up for these reactors. So, the aim of the work presented here is to contribute to determine a core calculation methodology with CEA (Commissariat a l'Energie Atomique) codes. Vapour production in the reactor core involves great differences in technological options from pressurised water reactor. We analyse main physical phenomena for BWR and offer solutions taking them into account. BWR fuel assembly heterogeneity causes steep thermal flux gradients. The two dimensional collision probability method with exact boundary conditions makes possible to calculate accurately the flux in BWR fuel assemblies using the APOLLO-2 lattice code but induces a very long calculation time. So, we determine a new methodology based on a two-level flux calculation. Void fraction variations in assemblies involve big spectrum changes that we have to consider in core calculation. We suggest to use a void history parameter to generate cross-sections libraries for core calculation. The core calculation code has also to calculate the depletion of main isotopes concentrations. A core calculation associating neutronics and thermal-hydraulic codes lays stress on points we still have to study out. The most important of them is to take into account the control blade in the different calculation stages. (author)
Bouveret, F
2001-07-01
Although Boiling Water Reactors generate a quarter of worldwide nuclear electricity, they have been only little studied in France. A certain interest now shows up for these reactors. So, the aim of the work presented here is to contribute to determine a core calculation methodology with CEA (Commissariat a l'Energie Atomique) codes. Vapour production in the reactor core involves great differences in technological options from pressurised water reactor. We analyse main physical phenomena for BWR and offer solutions taking them into account. BWR fuel assembly heterogeneity causes steep thermal flux gradients. The two dimensional collision probability method with exact boundary conditions makes possible to calculate accurately the flux in BWR fuel assemblies using the APOLLO-2 lattice code but induces a very long calculation time. So, we determine a new methodology based on a two-level flux calculation. Void fraction variations in assemblies involve big spectrum changes that we have to consider in core calculation. We suggest to use a void history parameter to generate cross-sections libraries for core calculation. The core calculation code has also to calculate the depletion of main isotopes concentrations. A core calculation associating neutronics and thermal-hydraulic codes lays stress on points we still have to study out. The most important of them is to take into account the control blade in the different calculation stages. (author)
Efimov Physics and the Three-Body Parameter within a Two-Channel Framework
Sørensen, Peder Klokmose; V. Fedorov, D.; S. Jensen, A.
2012-01-01
scaling laws. We recover known results for broad Feshbach resonances with small effective range, whereas in the case of narrow resonances we find a distinct non-monotonic behavior of the threshold at which the lowest Efimov trimer merges with the three-body continuum. To address the issue of the physical...... origin of the three-body parameter we provide a physically clear model for the relation between three-body physics and typical two-body atom-atom interactions. Our results demonstrate that experimental information from narrow Feshbach resonances and/or mixed systems are of vital importance to pin down...... the relation of two- and three-body physics in atomic systems....
Simon-Cornu, Marie; Mourlon, Christophe; Bordy, J.M.; Daures, J.; Dusiac, D.; Moignau, F.; Gouriou, J.; Million, M.; Moreno, B.; Chabert, I.; Lazaro, D.; Barat, E.; Dautremer, T.; Montagu, T.; Agelou, M.; De Carlan, L.; Patin, D.; Le Loirec, C.; Dupuis, P.; Gassa, F.; Guerin, L.; Batalla, A.; Leni, Pierre-Emmanuel; Laurent, Remy; Gschwind, Regine; Makovicka, Libor; Henriet, Julien; Salomon, Michel; Vivier, Alain; Lopez, Gerald; Dossat, C.; Pourrouquet, P.; Thomas, J.C.; Sarie, I.; Peyrard, P.F.; Chatry, N.; Lavielle, D.; Loze, R.; Brun, E.; Damian, F.; Diop, C.; Dumonteil, E.; Hugot, F.X.; Jouanne, C.; Lee, Y.K.; Malvagi, F.; Mazzolo, A.; Petit, O.; Trama, J.C.; Visonneau, T.; Zoia, A.; Courageot, Estelle; Gaillard-Lecanu, Emmanuelle; Kutschera, Reinald; Le Meur, Gaelle; Uzio, Fabien; De Conto, Celine; Gschwind, Regine; Makovicka, Libor; Farah, Jad; Martinetti, Florent; Sayah, Rima; Donadille, Laurent; Herault, Joel; Delacroix, Sabine; Nauraye, Catherine; Lee, Choonsik; Bolch, Wesley; Clairand, Isabelle; Horodynski, Jean-Michel; Pauwels, Nicolas; Robert, Pierre; VOLLAIRE, Joachim; Nicoletti, C.; Kitsos, S.; Tardy, M.; Marchaud, G.; Stankovskiy, Alexey; Van Den Eynde, Gert; Fiorito, Luca; Malambu, Edouard; Dreuil, Serge; Mougeot, X.; Be, M.M.; Bisch, C.; Villagrasa, C.; Dos Santos, M.; Clairand, I.; Karamitros, M.; Incerti, S.; Petitguillaume, Alice; Franck, Didier; Desbree, Aurelie; Bernardini, Michela; Labriolle-Vaylet, Claire de; Gnesin, Silvano; Leadermann, Jean-Pascal; Paterne, Loic; Bochud, Francois O.; Verdun, Francis R.; Baechler, Sebastien; Prior, John O.; Thomassin, Alain; Arial, Emmanuelle; Laget, Michael; Masse, Veronique; Saldarriaga Vargas, Clarita; Struelens, Lara; Vanhavere, Filip; Perier, Aurelien; Courageot, Estelle; Gaillard-Lecanu, Emmanuelle; Le-Meur, Gaelle; Monier, Catherine; Thers, Dominique; Le-Guen, Bernard; Blond, Serge; Cordier, Gerard; Le Roy, Maiwenn; De Carlan, Loic; Bordy, Jean-Marc; Caccia, Barbara; Andenna, Claudio; Charimadurai, Arun; Selvam, T Palani; Czarnecki, Damian; Zink, Klemens; Gschwind, Regine; Martin, Eric; Huot, Nicolas; Zoubair, Mariam; El Bardouni, Tarek; Lazaro, Delphine; Barat, Eric; Dautremer, Thomas; Montagu, Thierry; Chabert, Isabelle; Guerin, Lucie; Batalla, Alain; Moignier, C.; Huet, C.; Bassinet, C.; Baumann, M.; Barraux, V.; Sebe-Mercier, K.; Loiseau, C.; Batalla, A.; Makovicka, L.; Desnoyers, Yvon; Juhel, Gabriel; Mattera, Christophe; Tempier, Maryline
2014-03-01
These scientific days were organised by the 'technical protection' Section of the French Society of Radiation Protection (SFRP) in cooperation with the French society of medical physicists (SFPM), the Swiss Romandie association of radioprotection (ARRAD) and the associated laboratories of radio-physics and dosimetry (LARD). The objective of these days was to review the existing calculation codes used in radiation transport, source estimation and dose management, and to identify some future prospects. This document brings together the available presentations (slides) together with their corresponding abstracts (in French) and dealing with: 1 - Presentation of the conference days (L. De Carlan); 2 - Simulating radionuclide transfers in the environment: what calculation codes and for what? (C. Mourlon); 3 - Contribution of Monte-Carlo calculation to the theoretical foundation analysis of calibration procedures and dosemeters design for radioprotection photon dosimetry (J.M. Bordy); 4 - Use of calculation codes in R and D for the development of a new passive dosemeter for photons and beta radiations (B. Moreno); 5 - Development of a new virtual sources model for the Monte-Carlo prediction of EPID (Electronic Portal Imaging Device) images and implementation in PENELOPE (I. Chabert); 6 - Prediction of high-resolution EPID images for in-vivo dosimetry (D. Patin); 7 - 4D thorax modeling by artificial neural networks (P.E. Leni); 8 - Presentation of the calculation utilities of the book 'Calculation of ionizing radiations generated doses' (Vivier, Lopez, EDP Sciences 2012) (A. Vivier); 9 - RayXpert C : a 3D modeling and Monte-Carlo dose rate calculation software (C. Dossat); 10 - TRIPOLI-4 R Version 9 S Monte-Carlo code for radioprotection (F. Damian); 11 - Realistic radioprotection training with the digital school workshop (E. Courageot); 12 - Use of BEAMNRC code for dental prostheses influence evaluation in ENT cancers treatment by external radiotherapy (C. De Conto); 13
Brambilla, Giovanni; Maffei, Luigi; Di Gabriele, Maria; Gallo, Veronica
2013-07-01
An experimental study was carried out in 20 squares in the center of Rome, covering a wide range of different uses, sonic environments, geometry, and architectural styles. Soundwalks along the perimeter of each square were performed during daylight and weekdays taking binaural and video recordings, as well as spot measurements of illuminance. The cluster analysis performed on the physical parameters, not only acoustic, provided two clusters that are in satisfactory agreement with the "a priori" classification. Applying the principal component analysis (PCA) to five physical parameters, two main components were obtained which might be associated to two environmental features, namely, "chaotic/calm" and "open/enclosed." On the basis of these two features, six squares were selected for the laboratory audio-video tests where 32 subjects took part filling in a questionnaire. The PCA performed on the subjective ratings on the sonic environment showed two main components which might be associated to two emotional meanings, namely, "calmness" and "vibrancy." The linear regression modeling between five objective parameters and the mean value of subjective ratings on chaotic/calm and enclosed/open attributes showed a good correlation. Notwithstanding these interesting results being limited to the specific data set, it is worth pointing out that the complexity of the soundscape quality assessment can be more comprehensively examined merging the field measurements of physical parameters with the subjective ratings provided by field and/or laboratory tests.
Petrović-Oggiano Gordana
2009-01-01
Full Text Available The aim of present study was to investigate the effects of three different types of physical activity on reduction of the metabolic parameters mainly responsible for cardiovascular diseases. This prospective-intervention study was performed at the 'ČIGOTA' Thyroid Institute on Mt. Zlatibor (Serbia between August 2004 and June 2006. Sixty-eight overweight/obese patients aged 40-70 years with hyperlipidemia were divided into three groups according to their weight and overall health. The program of physical workout included: group I - fast walking; group II - gymnastic exercises and specially chosen exercises in the swimming pool; and group III - combined physical training of higher intensity and greater length. All patients were also on a special reduced diet of 1000 kcal per day, the AHA step-2 diet. We monitored the body mass index, body composition, glucose, cholesterol (total, LDL-, and HDL-, and triglycerides before, during, and after the intervention. After 2 and particularly 12 weeks of intervention, a significant improvement of all metabolic parameters was achieved in all three groups of patients. Although most patients completed the study with normal values of all parameters, the most desirable results were achieved in group III (combined exercises with an average energy expenditure of 900 kcal per day. Our research indicates that a specially conceived program of physical activity and diet intervention resulted in significant reduction of cardiovascular risk factors.
Park, Byoung Yoon; Hansen, Francis D.
2004-01-01
The regulatory compliance determination for the Waste Isolation Pilot Plant includes the consideration of room closure. Elements of the geomechanical processes include salt creep, gas generation and mechanical deformation of the waste residing in the rooms. The WIPP was certified as complying with regulatory requirements based in part on the implementation of room closure and material models for the waste. Since the WIPP began receiving waste in 1999, waste packages have been identified that are appreciably more robust than the 55-gallon drums characterized for the initial calculations. The pipe overpack comprises one such waste package. This report develops material model parameters for the pipe overpack containers by using axisymmetrical finite element models. Known material properties and structural dimensions allow well constrained models to be completed for uniaxial, triaxial, and hydrostatic compression of the pipe overpack waste package. These analyses show that the pipe overpack waste package is far more rigid than the originally certified drum. The model parameters developed in this report are used subsequently to evaluate the implications to performance assessment calculations
Development of M3C code for Monte Carlo reactor physics criticality calculations
Kumar, Anek; Kannan, Umasankari; Krishanani, P.D.
2015-06-01
The development of Monte Carlo code (M3C) for reactor design entails use of continuous energy nuclear data and Monte Carlo simulations for each of the neutron interaction processes. BARC has started a concentrated effort for developing a new general geometry continuous energy Monte Carlo code for reactor physics calculation indigenously. The code development required a comprehensive understanding of the basic continuous energy cross section sets. The important features of this code are treatment of heterogeneous lattices by general geometry, use of point cross sections along with unionized energy grid approach, thermal scattering model for low energy treatment, capability of handling the microscopic fuel particles dispersed randomly. The capability of handling the randomly dispersed microscopic fuel particles which is very useful for the modeling of High-Temperature Gas-Cooled reactor fuels which are composed of thousands of microscopic fuel particle (TRISO fuel particle), randomly dispersed in a graphite matrix. The Monte Carlo code for criticality calculation is a pioneering effort and has been used to study several types of lattices including cluster geometries. The code has been verified for its accuracy against more than 60 sample problems covering a wide range from simple (like spherical) to complex geometry (like PHWR lattice). Benchmark results show that the code performs quite well for the criticality calculation of the system. In this report, the current status of the code, features of the code, some of the benchmark results for the testing of the code and input preparation etc. are discussed. (author)
Wolf, Alexander; Reiher, Markus; Hess, Bernd Artur
2004-05-08
The first molecular calculations with the generalized Douglas-Kroll method up to fifth order in the external potential (DKH5) are presented. We study the spectroscopic parameters and electron affinity of the tin oxide molecule SnO and its anion SnO(-) applying nonrelativistic as well as relativistic calculations with higher orders of the DK approximation. In order to guarantee highly accurate results close to the basis set limit, an all-electron basis for Sn of at least quintuple-zeta quality has been constructed and optimized. All-electron CCSD(T) calculations of the potential energy curves of both SnO and SnO(-) reproduce the experimental values very well. Relative energies and valence properties are already well described with the established standard second-order approximation DKH2 and the higher-order corrections DKH3-DKH5 hardly affect these quantities. However, an accurate description of total energies and inner-shell properties requires superior relativistic schemes up to DKH5. (c) 2004 American Institute of Physics.
Huang Can
2014-08-01
Full Text Available In the present paper, a numerical model combining radiation and conduction for porous materials is developed based on the finite volume method. The model can be used to investigate high-temperature thermal insulations which are widely used in metallic thermal protection systems on reusable launch vehicles and high-temperature fuel cells. The effective thermal conductivities (ECTs which are measured experimentally can hardly be used separately to analyze the heat transfer behaviors of conduction and radiation for high-temperature insulation. By fitting the effective thermal conductivities with experimental data, the equivalent radiation transmittance, absorptivity and reflectivity, as well as a linear function to describe the relationship between temperature and conductivity can be estimated by an inverse problems method. The deviation between the calculated and measured effective thermal conductivities is less than 4%. Using the material parameters so obtained for conduction and radiation, the heat transfer process in multilayer thermal insulation (MTI is calculated and the deviation between the calculated and the measured transient temperatures at a certain depth in the multilayer thermal insulation is less than 6.5%.
Transition to a Source with Modified Physical Parameters by Energy Supply or Using an External Force
Kucherov, A. N.
2017-11-01
A study has been made of the possibility for the physical parameters of a source/sink, i.e., for the enthalpy, temperature, total pressure, maximum velocity, and minimum dimension, at a constant radial Mach number to be changed by energy or force action on the gas in a bounded zone. It has been shown that the parameters can be controlled at a subsonic, supersonic, and transonic (sonic in the limit) radial Mach number. In the updated source/sink, all versions of a vortex-source combination can be implemented: into a vacuum, out of a vacuum, into a submerged space, and out of a submerged space, partially or fully.
Daily, Michael D. [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Chun, Jaehun [Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Heredia-Langner, Alejandro [National Security Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Wei, Guowei [Department of Mathematics, Michigan State University, East Lansing, Michigan 48824 (United States); Baker, Nathan A. [Computational and Statistical Analytics Division, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)
2013-11-28
Implicit solvent models are important tools for calculating solvation free energies for chemical and biophysical studies since they require fewer computational resources but can achieve accuracy comparable to that of explicit-solvent models. In past papers, geometric flow-based solvation models have been established for solvation analysis of small and large compounds. In the present work, the use of realistic experiment-based parameter choices for the geometric flow models is studied. We find that the experimental parameters of solvent internal pressure p = 172 MPa and surface tension γ = 72 mN/m produce solvation free energies within 1 RT of the global minimum root-mean-squared deviation from experimental data over the expanded set. Our results demonstrate that experimental values can be used for geometric flow solvent model parameters, thus eliminating the need for additional parameterization. We also examine the correlations between optimal values of p and γ which are strongly anti-correlated. Geometric analysis of the small molecule test set shows that these results are inter-connected with an approximately linear relationship between area and volume in the range of molecular sizes spanned by the data set. In spite of this considerable degeneracy between the surface tension and pressure terms in the model, both terms are important for the broader applicability of the model.
THE EFFECTS OF PHYSICAL TRAINING ON CARDIOVASCULAR PARAMETERS AND REDUCTION OF VISCERAL FATTY TISSUE
Todorka Savic
2007-12-01
Full Text Available Regular physical activity and good physical condition are widely accepted as factors that reduce all-cause mortality and improve a number of health outcomes.The aim of this study was to investigate the effects of aerobic exercise training on cardiovascular parameters and reduction of visceral obesity in patients with stable coronary artery disease participating in a cardiovascular rehabilitation exercise program. Fifty-two patients with stable coronary heart disease who had been accepted into the outpatient Phase II cardiovascular rehabilitation program at the Institute for Treatment and Rehabilitation of Cardiovascular Diseases Niska Banja, Nis, Serbia,were recruited for this study. All patients were divided into two groups: group with stable coronary heart disease who had regular aerobic physical training during 6weeks and control without physical training. There were not significant differences in body weight, body mass index, waist circumference and waist /hip ratio in start and at the end of physical training program. Physical training did not reduce the above mentioned parameters after 6 weeks. There were not significant differences in systolic and diastolic blood pressure at the beginning and at the end of the observed period.In group with physical training, a significant reduction of systolic and diastolic blood pressure after cardiovascular rehabilitation were reported (p<0.05. In patients with moderate aerobic physical training, a significant decrease in the heart rate was registered after the 6-week follow-up (p<0.05, while heart rate was significantly lower in this group compared to group with sedentary lifestyle (p<0.05. The effects of the 6-week cardiovascular rehabilitation on lipid parameters is visible only in slight reduction of triglyceride values in group with physical training (p<0.05. The concentration of triglycerides were significantly lower in this group compared to sedentary patients after the 6-week follow-up (p<0
Chemical Abundances and Physical Parameters of H II Regions in the Magellanic Clouds
Reyes, R. E. C.
The chemical abundances and physical parameters of H II regions are important pa rameters to determine in order to understand how stars and galaxies evolve. The Magellanic Clouds offer us a unique oportunity to persue such studies in low metallicity galaxies. In this contribution we present the results of the photoionization modeling of 5 H II regions in each of the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) sys tems. Optical data were collected from the literature, complemented by our own observa tions (Carlos Reyes et al. 1998), including UV spectra from the new IUE data ban k and infrared fluxes from the IRAS satellite. The chemical abundances of He, C, N, O, Ne, S, Ar and physical parameters like the densities, the ionized masses, the luminosities, the ionization temperatures , the filling factor and optical depth are determined. A comparison of the abundances of these HII regions with those of typical planetary nebulae and supergiants stars is also presented.
Identification of AE Bursts by Classification of Physical and Statistical Parameters
Mieza, J.I.; Oliveto, M.E.; Lopez Pumarega, M.I.; Armeite, M.; Ruzzante, J.E.; Piotrkowski, R.
2005-01-01
Physical and statistical parameters obtained with the Principal Components method, extracted from Acoustic Emission bursts coming from triaxial deformation tests were analyzed. The samples came from seamless steel tubes used in the petroleum industry and some of them were provided with a protective coating. The purpose of our work was to identify bursts originated in the breakage of the coating, from those originated in damage mechanisms in the bulk steel matrix. Analysis was performed by statistical distributions, fractal analysis and clustering methods
Impact of moderator history on physics parameters in pressurized water reactors
Mosteller, R.D.
1988-01-01
The magnitude of differential reactivity effects that result from spectral differences in different portions of a pressurized water (PWR) core is studied, and it is shown that these effects can be correlated very well with the local moderator history. The impact of these differences on physics parameters such as axial offset, isothermal moderator temperature coefficient, and differential control rod worth is shown to be significant for two PWRs of considerably different design
Chemical-physical parameters of atmospheric precipitations in the Pisa urban area
Paradossi, C.; Marchini, F.
1998-01-01
In the work the major chemical-physical parameters of the rain collected in May 1992 - May 1993 period in Pisa are studied and discussed. The ph analysis was particular interesting. Indeed sometimes it reached values between 4.5 and 5.0. Also the ions examined although they did not reach values supposed to cause damage, were subjected to monthly variations. This paper confirms previously results. Pisa although not being considered an industrial area is subjected to pollutant acid rains [it
Stochasticity effects on derivation of physical parameters of unresolved star clusters
de Meulenaer, Philippe; Narbutis, Donatas; Mineikis, Tadas; Vansevičius, Vladas
2013-01-01
We developed a method for a fast modeling of broad-band UBVRI integrated magnitudes of unresolved star clusters and used it to derive their physical parameters (age, mass, and extinction). The method was applied on M33 galaxy cluster sample and consistency of ages and masses derived from unresolved observations with the values derived from resolved stellar photometry was demonstrated. We found that interstellar extinction causes minor age-extinction degeneracy for the studied sample due to a ...
PEM fuel cell model and simulation in Matlab–Simulink based on physical parameters
Abdin, Z.; Webb, C.J.; Gray, E.MacA.
2016-01-01
An advanced PEM fuel cell mathematical model is described and realised in four ancillaries in the Matlab–Simulink environment. Where possible, the model is based on parameters with direct physical meaning, with the aim of going beyond empirically describing the characteristics of the fuel cell. The model can therefore be used to predict enhanced performance owing to, for instance, improved electrode materials, and to relate changes in the measured performance to internal changes affecting influential physical parameters. Some simplifying assumptions make the model fairly light in computational demand and therefore amenable to extension to simulate an entire fuel-cell stack as part of an energy system. Despite these assumptions, the model emulates experimental data well, especially at high current density. The influences of pressure, temperature, humidification and reactant partial pressure on cell performance are explored. The dominating effect of membrane hydration is clearly revealed. - Highlights: • Model based on physical parameters where possible. • Effective binary diffusion modelled in detail on an atomistic basis. • The dominating effect of membrane hydration is clearly revealed. • Documented Simulink model so others can use it. • Conceived as a research tool for exploring enhanced fuel cell performance and diagnosing problems.
Antov, A.; Stoyanova, I.
2008-01-01
In conjunction with each refuelling shutdown of the reactor core, nuclear design calculations are performed to ensure that the reactor physics characteristics of the new core will be consistent with the safety limits. Prior to return to normal operation, a physics test program is required to determine if the operating characteristics of the core are consistent with the design predictions and to ensure that the core can be operated as designed. Successful completion of the physics test program is demonstrated when the test results agree with the predicted results within predetermined test criteria. Successful completion of the physics test program and successful completion of other tests, which are performed after each refuelling provides assurance that the plant can be operated as designed. The calculated neutron-physics characteristics values of Kozloduy NPP Unit 5 and Unit 6 (WWER 1000) obtained by the computer code package KASKAD are compared with the obtained results during the start up physics tests. The core fuel loading consists of 163 fuel assemblies (FAs). The calculated values are given according to actual experimental conditions of the reactor core during start up physics tests. The report includes comparisons between calculation results by code package KASKAD (BIPR7A) and experimental data values of main neutron-physics characteristics during start up physics tests in selected recent cycles of Kozloduy NPP Unit 5 and Unit 6. (authors)
Stoyanova, I.; Antov, A.
2007-01-01
In conjunction with each refuelling shutdown of the reactor core, nuclear design calculations are performed to ensure that the reactor physics characteristics of the new core will be consistent with the safety limits. Prior to return to normal operation, a physics test program is required to determine if the operating characteristics of the core are consistent with the design predictions and to ensure that the core can be operated as designed. Successful completion of the physics test program is demonstrated when the test results agree with the predicted results within predetermined test criteria. Successful completion of the physics test program and successful completion of other tests which are performed after each refuelling provides assurance that the plant can be operated as designed. The calculated neutron-physics characteristics values of Kozloduy NPP Unit 5 and Unit 6 (WWER 1000) obtained by the computer code package KASKAD are compared with the obtained results during the start up physics tests. The core fuel loading consists of 163 fuel assemblies. The calculated values are given according to actual experimental conditions of the reactor core during start up physics tests. The report includes comparisons between calculation results by code package KASKAD (BIPR7A) and experimental data values of main neutron-physics characteristics during start up physics tests in selected recent cycles of Kozloduy NPP Unit 5 and Unit 6 (Authors)
Mirvakili, S.M.; Faghihi, F.; Khalafi, H.
2012-01-01
Highlights: ► Thermal–hydraulics parameters of a VVER-1000 core based on neural network (ANN), are carried out. ► Required data for ANN training are found based on modified COBRA-EN code and then linked each other using MATLAB software. ► Based on ANN method, average and maximum temperature of fuel and clad as well as MDNBR of each FA are predicted. -- Abstract: The main goal of the present article is to design a computational tool to predict physical parameters of the VVER-1000 nuclear reactor core based on artificial neural network (ANN), taking into account a detailed physical model of the fuel rods and coolant channels in a fuel assembly. Predictions of thermal characteristics of fuel, clad and coolant are performed using cascade feed forward ANN based on linear fission power distribution and power peaking factors of FAs and hot channels factors (which are found based on our previous neutronic calculations). A software package has been developed to prepare the required data for ANN training which applies a modified COBRA-EN code for sub-channel analysis and links the codes using the MATLAB software. Based on the current estimation system, five main core TH parameters are predicted, which include the average and maximum temperatures of fuel and clad as well as the minimum departure from nucleate boiling ratio (MDNBR) for each FA. To get the best conditions for the considered ANNs training, a comprehensive sensitivity study has been performed to examine the effects of variation of hidden neurons, hidden layers, transfer functions, and the learning algorithms on the training and simulation results. Performance evaluation results show that the developed ANN can be trained to estimate the core TH parameters of a typical VVER-1000 reactor quickly without loss of accuracy.
Nguyen Tuan Khai; Hoang Van Khanh; Phan Quoc Vuong; Tran Viet Phu; Tran Vinh Thanh; Nguyen Thi Mai Huong; Nguyen Thi Dung; Le Tran Chung; Nguyen Minh Tuan; Tran Quoc Duong
2014-01-01
The project aims at nuclear human resource development and enhancement in research capability in reactor physics and kinetics at Nuclear Energy Center (Institute for Nuclear Science and Technology) and Nuclear Reactor Center (Nuclear Research Institute, Dalat). The main research items of the project can be summarized as follows: i) Considering possibility on using modern calculation techniques and methods in investigating neutronic characteristics and neutronics-thermal hydraulics coupling. This item is proposed to carry out based on international collaboration with Prof. Le Trong Thuy, San Jose University, US; ii) Carrying out the collaborative activities in research and training between Nuclear Energy Center (Institute for Nuclear Science and Technology) and Nuclear Reactor Center (Nuclear Research Institute, Dalat); iii) Opening two-week training course on nuclear reactor engineering (25 Nov - 12 Dec 2013) in collaboration with Japan Atomic Energy Agency (JAEA). (author)
Uğur YALÇIN
2004-02-01
Full Text Available In this study, quasi-optical scattering of finite source electromagnetic waves from a dielectric coated cylindrical surface is analysed with Physical Optics (PO approach. A linear electrical current source is chosen as the finite source. Reflection coefficient of the cylindrical surface is derived by using Geometrical Theory of Diffraction (GTD. Then, with the help of this coefficient, fields scattered from the surface are obtained. These field expressions are used in PO approach and surface scattering integral is determined. Evaluating this integral asymptotically, fields reflected from the surface and surface divergence coefficient are calculated. Finally, results obtained in this study are evaluated numerically and effects of the surface impedance to scattered fields are analysed. The time factor is taken as j te? in this study.
Assessing first-order emulator inference for physical parameters in nonlinear mechanistic models
Hooten, Mevin B.; Leeds, William B.; Fiechter, Jerome; Wikle, Christopher K.
2011-01-01
We present an approach for estimating physical parameters in nonlinear models that relies on an approximation to the mechanistic model itself for computational efficiency. The proposed methodology is validated and applied in two different modeling scenarios: (a) Simulation and (b) lower trophic level ocean ecosystem model. The approach we develop relies on the ability to predict right singular vectors (resulting from a decomposition of computer model experimental output) based on the computer model input and an experimental set of parameters. Critically, we model the right singular vectors in terms of the model parameters via a nonlinear statistical model. Specifically, we focus our attention on first-order models of these right singular vectors rather than the second-order (covariance) structure.
Negro, M.J.; Manzanares, P.; Oliva, J.M.; Ballesteros, I.; Ballesteros, M. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain). Departamento de Energias Renovables
2003-09-01
Steam-explosion process can be satisfactorily used as a pretreatment in ethanol production from lignocellulosic biomass. Traditionally, pretreatment effectiveness is evaluated in terms of hemicellulose solubilization, enzymatic convertibility of cellulosic fraction, and recovery of both polysaccharides. In this study some parameters different from composition (main components) have been evaluated as an alternative tool to characterise the effect of steaming pretreatment on lignocellulosic materials. The effect of the most important variables in steam explosion pretreatment (temperature, residence time and chip size) on various physical/chemical parameters of pine biomass were investigated. Changes in O/C and H/C atomic ratios, colour analysis, elementary composition, water drop penetration time, organic soluble content, cellulose crystallinity index, and thermogravimetric analysis after the pretreatment were evaluated. Furthermore the influence of operational pretreatment variables on all such parameters and their interactions were examined with the Yates' algorithm. (author)
Negro, M.J.; Manzanares, P.; Oliva, J.M.; Ballesteros, I.; Ballesteros, M.
2003-01-01
Steam-explosion process can be satisfactorily used as a pretreatment in ethanol production from lignocellulosic biomass. Traditionally, pretreatment effectiveness is evaluated in terms of hemicellulose solubilization, enzymatic convertibility of cellulose fraction, and recovery of both polysaccharides. In this study some parameters different from composition (main components) have been evaluated as an alternative tool to characterise the effect of steaming pretreatment on lignocellulosic materials. The effect of the most important variables in steam explosion pretreatment (temperature, residence time and chip size) on various physical/chemical parameters of pine biomass were investigated. Changes in O/C and H/C atomic ratios, colour analysis, elementary composition, water drop penetration time, organic soluble content, cellulose cristallinity index, and thermogravimetric analysis after the pretreatment were evaluated. Furthermore the influence of operational pretreatment variables on all such parameters and their interactions were examined with the Yates' algorithm
Ye, Yong-Jun; Zhang, Yun-Feng; Dai, Xin-Tao; Ding, De-Xin
2017-10-01
The particle size and heaped methods of exhalation media have important effects on physical parameters, such as the free radon production rate, porosity, permeability, and radon diffusion coefficient. However, existing methods for determining those parameters are too complex, and time-consuming. In this study, a novel, systematic determining method was proposed based on nuclide decay, radon diffusion migration theory, and the mass conservation law, and an associated experimental device was designed and manufactured. The parameters of uranium ore heap and sandy soil of radon diffusion coefficient (D), free radon production rate (α), media permeability (k), and porosity (ε) were obtained. At the same time, the practicality of the novel determining method was improved over other methods, with the results showing that accuracy was within the acceptable range of experimental error. This novel method will be of significance for the study of radon migration and exhalation in granulated porous media. Copyright © 2017 Elsevier Ltd. All rights reserved.
Frese, G.; Hebrank, F.X.; Renz, W.; Storch, T.
1998-01-01
Purpose: The standards and regulations concerning the protection of patients and operator staff within the context of MRI are compiled. Resulting consequences regarding physical parameters are evaluated. Material and methods: The static magnetic field, heating effects caused by RF-fields and acoustical noise are outlined. The actual boundaries of these parameters are compared against the relevant published standards. Peripheral stimulation limits due to pulsed gradient fields have been determined in a new clinical study. Results: Many parameters recommended for the normal operating mode are already exceeded during routine MRI. Referring to our clinical study, we found that limits recommended in the MRI relevant standards are unnecessarily conservative and can actually be doubled. (orig./AJ) [de
Research on physical and chemical parameters of coolant in Light-Water Reactors
Reis, Isabela C.; Mesquita, Amir Z., E-mail: icr@cdtn.br, E-mail: amir@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEM-MG), Belo Horizonte, MG (Brazil)
2015-07-01
The coolant radiochemical monitoring of light-water reactors, both power reactor as research reactors is one most important tasks of the system safe operation. The last years have increased the interest in the coolant chemical studying to optimize the process, to minimize the corrosion, to ensure the primary system materials integrity, and to reduce the workers exposure radiation. This paper has the objective to present the development project in Nuclear Technology Development Center (CDTN), which aims to simulate the primary water physical-chemical parameters of light-water-reactors (LWR). Among these parameters may be cited: the temperature, the pressure, the pH, the electric conductivity, and the boron concentration. It is also being studied the adverse effects that these parameters can result in the reactor integrity. The project also aims the mounting of a system to control and monitoring of temperature, electric conductivity, and pH of water in the Installation of Test in Accident Conditions (ITCA), located in the Thermal-Hydraulic Laboratory at CDTN. This facility was widely used in the years 80/90 for commissioning of several components that were installed in Angra 2 containment. In the test, the coolant must reproduce the physical and chemical conditions of the primary. It is therefore fundamental knowledge of the main control parameters of the primary cooling water from PWR reactors. Therefore, this work is contributing, with the knowledge and the reproduction with larger faithfulness of the reactors coolant in the experimental circuits. (author)
Physically based model for extracting dual permeability parameters using non-Newtonian fluids
Abou Najm, M. R.; Basset, C.; Stewart, R. D.; Hauswirth, S.
2017-12-01
Dual permeability models are effective for the assessment of flow and transport in structured soils with two dominant structures. The major challenge to those models remains in the ability to determine appropriate and unique parameters through affordable, simple, and non-destructive methods. This study investigates the use of water and a non-Newtonian fluid in saturated flow experiments to derive physically-based parameters required for improved flow predictions using dual permeability models. We assess the ability of these two fluids to accurately estimate the representative pore sizes in dual-domain soils, by determining the effective pore sizes of macropores and micropores. We developed two sub-models that solve for the effective macropore size assuming either cylindrical (e.g., biological pores) or planar (e.g., shrinkage cracks and fissures) pore geometries, with the micropores assumed to be represented by a single effective radius. Furthermore, the model solves for the percent contribution to flow (wi) corresponding to the representative macro and micro pores. A user-friendly solver was developed to numerically solve the system of equations, given that relevant non-Newtonian viscosity models lack forms conducive to analytical integration. The proposed dual-permeability model is a unique attempt to derive physically based parameters capable of measuring dual hydraulic conductivities, and therefore may be useful in reducing parameter uncertainty and improving hydrologic model predictions.
Chowdhury, Md Albarune; de Neergaard, Andreas; Jensen, Lars Stoumann
2014-01-01
Solid-liquid separation of animal slurry, with solid fractions used for composting, has gained interest recently. However, efficient composting of separated animal slurry solid fractions (SSFs) requires a better understanding of the process dynamics in terms of important physical parameters...... and their interacting physical relationships in the composting matrix. Here we monitored moisture content, bulk density, particle density and air-filled porosity (AFP) during composting of SSF collected from four commercially available solid-liquid separators. Composting was performed in laboratory-scale reactors...... for 30 days (d) under forced aeration and measurements were conducted on the solid samples at the beginning of composting and at 10-d intervals during composting. The results suggest that differences in initial physical properties of SSF influence the development of compost maximum temperatures (40...
Physical parameters and biological effects of the LVR-15 epithermal neutron beam
Burian, J.; Marek, M.; Rejchrt, J.; Viererbl, L.; Gambarini, G.; Mares, V.; Vanossi, E.; Judas, L.
2006-01-01
Monitoring of the physical and biological properties of the epithermal neutron beam constructed at the multipurpose LVR-15 nuclear reactor for NCT therapy of brain tumors showed that its physical and biological properties are stable in time and independent on an ad hoc reconfiguration of the reactor core before its therapeutic use. Physical parameters were monitored by measurement of the neutron spectrum, neutron profile, fast neutron kerma rate in tissue and photon absorbed dose, the gel dosimetry was used with the group of standard measurement methods. The RBE of the beam, as evaluated by 3 different biological models, including mouse intestine crypt regeneration assay, germinative zones of the immature rat brain and C6 glioma cells in culture, ranged from 1.70 to 1.99. (author)
Bosevski, T.; Strugar, P.
1966-10-01
In determining the criticality parameters of a two-zone reactor with flat central zone one encounters a numerical problem requiring the solution of a system of two non-linear equations. To solve them the Newton method, which proved convenient, was used n this work. By comparing our results with those reported one obtains about 5% smaller values of both the radius of the flat zone and of the radial buckling of the outer zone. This discrepancy probably results from some approximations used in solving the same system of equations used in solving the same system of equations where the procedure form was applied, whereas the calculation time is by one order of magnitude smaller
Avram, C.N. [Faculty of Physics, West University of Timisoara, Bd. V. Parvan No. 4, 300223 Timisoara (Romania); Gruia, A.S., E-mail: adigruia@yahoo.com [Faculty of Physics, West University of Timisoara, Bd. V. Parvan No. 4, 300223 Timisoara (Romania); Brik, M.G. [College of Sciences, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China); Institute of Physics, University of Tartu, Ravila 14C, Tartu 50411 (Estonia); Institute of Physics, Jan Dlugosz University, Armii Krajowej 13/15, PL-42200 Czestochowa (Poland); Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw (Poland); Barb, A.M. [Faculty of Physics, West University of Timisoara, Bd. V. Parvan No. 4, 300223 Timisoara (Romania)
2015-12-01
Calculations of the Cr{sup 3+} energy levels, spin-Hamiltonian parameters and vibrational spectra for the layered CrCl{sub 3} crystals are reported for the first time. The crystal field parameters and the energy level scheme were calculated in the framework of the Exchange Charge Model of crystal field. The spin-Hamiltonian parameters (zero-field splitting parameter D and g-factors) for Cr{sup 3+} ion in CrCl{sub 3} crystals were obtained using two independent techniques: i) semi-empirical crystal field theory and ii) density functional theory (DFT)-based model. In the first approach, the spin-Hamiltonian parameters were calculated from the perturbation theory method and the complete diagonalization (of energy matrix) method. The infrared (IR) and Raman frequencies were calculated for both experimental and fully optimized geometry of the crystal structure, using CRYSTAL09 software. The obtained results are discussed and compared with the experimental available data.
Some calculation formulae for the candu 6 hypoid gearing. a physical point of view
Doca, C.; Paunoiu, C.
2015-01-01
The CANDU 6 reactor.s Adjuster Unit consists of a tubular, stainless steel, neutron absorbing element which is raised and lowered within a guide tube. The Adjuster Unit is suspended from a cable which is wound around the sheave of a drive mechanism. To provide a very fine ''up-down'' displacement of the absorbing element, the adjuster drive mechanism incorporates a hypoid-gearing containing a conical spiroid pinion and a conical spiroid gear , having their axes at rights angle. Here represents the gear.s teeth number. By its conical spiroid pinion, its spiroid gear with double-involute teeth, and its reduction (transmission) ratio , this hypoid-gearing seems to be a special type mechanism, not encountered (by the authors, at least) in the classical engineering textbooks, where the most analyzed examples only are for and . Elaborated from a physical point of view, the paper demonstrates and proposes a number of calculation formulae for the main geometrical elements of a same CANDU 6 hypoid-gearing. Finally, the paper presents a very good (exact, practically) superposition between the values obtained using the proposed calculation formulae, and the known CANDU 6 hypoid-gearing.s geometrical values. Al these general calculation formulae are helpful for well understanding the dynamics and kinematics of the adjuster drive mechanism, and represent the minimum needed knowledge for some possible applications, in other mechanical systems, of the hypoid-gearing with a so large reduction rate . 11N1502NiN15012NNi51N10050i150i. (authors)
Klein, Christoph
2011-09-23
Transitions of charmed hadrons are of significant importance, since they provide possibilities to extract the CKM matrix elements V{sub cd} and V{sub cs} from experimental data as well as interesting channels to search for new physics effects. However, quarks are bound in hadrons, and it is necessary to describe this effect in a reliable way, to study the underlying flavour dynamics. For this, one has to use nonperturbative tools, to determine the corresponding transition amplitudes. The results of such calculations can furthermore be of use, to test the predictions of QCD and to contribute to a deeper understanding of the structure of hadrons. In this thesis two topics are investigated using the method of QCD light-cone sum rules (LCSRs). The first topic consists in the form factors of the semileptonic decays D {yields} {pi}l{nu}{sub l} and D {yields} Kl{nu}{sub l}, for which new results are calculated using up-to-date input values. Since LCSRs are not applicable in the whole range of kinematics, they are extrapolated by the use of appropriate parametrisations and the results agree well with experimental data. The second topic are the transitions of charmed baryons to a nucleon. Here the corresponding transition form factors and in addition the hadronic {lambda}{sub c}D{sup (*)}N and {sigma}{sub c}D{sup (*)}N coupling constants are calculated - the latter by the consideration of double dispersion relations. These coupling constants are of special interest for the description of hadronic interactions, like open charm production in proton-antiprotoncollisions. Furthermore there appears the problem, that both parity states of a baryon contribute to the considered functional representation, for which a consistent way to separate them is presented. (orig.)
Bondarenko, Evgenii A
2011-01-01
Based on the analysis of a well-known system of equations describing the dynamics of a two-isotope laser gyro with an equal-Q resonator under conditions of its fine-tuning to the centre of the emission line and balanced currents in the discharge arms, we have derived the formulas for calculating the parameters of the synchronisation zone for the frequencies of counterpropagating electromagnetic waves generated in the device. The formulas make it possible to calculate the coordinates on the axis of the angular velocity of the left and right boundaries of the synchronisation zone, the coordinate of its centre and half-width. It follows from the analysis that, in the general case of the asymmetric linear coupling between the counterpropagating waves via backscattering, absorption, and transmission of radiation from the mirrors of the gyro, the left and right boundaries of the synchronisation zone are located at different distances with respect to the origin of coordinates, so that the centre of the region is displaced along the axis of the angular velocity. The analysis of the formulas also implies that the shift of the centre of the synchronisation zone and its half-width decrease with increasing medium gain.
Horacek, L.
1994-12-01
The parameters are summarized for a calculation of the probability of brittle fracture of the WWER-440 reactor pressure vessel (RPV). The parameters were selected for 2 basic approaches, viz., one based on the Monte Carlo method and the other on the FORM and SORM methods (First and Second Order Reliability Methods). The approaches were represented by US computer codes VISA-II and OCA-P and by the German ZERBERUS code. The philosophy of the deterministic and probabilistic aspects of the VISA-II code is outlined, and the differences between the US and Czech PWR's are discussed in this context. Briefly described is the partial approach to the evaluation of the WWER type RPV's based on the assessment of their resistance to brittle fracture by fracture mechanics tools and by using the FORM and SORM methods. Attention is paid to the input data for the WWER modification of the VISA-II code. The data are categorized with respect to randomness, i.e. to the stochastic or deterministic nature of their behavior. 18 tabs., 14 refs
Shane Stimpson
2017-09-01
Full Text Available An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly 2×. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilities have been demonstrated on two test cases: (1 a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications Progression Problem 2a and (2 a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly 3–4×, with a corresponding 15–20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of 2×. In total, the improvements yield roughly a 7–8× speedup. Given these performance benefits, these approaches have been adopted as the default in MPACT.
Stimpson, Shane G.; Liu, Yuxuan; Collins, Benjamin S.; Clarno, Kevin T.
2017-01-01
An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC) is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly 2×. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilities have been demonstrated on two test cases: (1) a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications) Progression Problem 2a and (2) a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly 3–4×, with a corresponding 15–20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of 2×. In total, the improvements yield roughly a 7–8× speedup. Furthermore given these performance benefits, these approaches have been adopted as the default in MPACT.
KHARKHARDIN Anatoly Nikolaevich
2016-08-01
Full Text Available Fiber reinforcement is the process of introduction of fibers of different origins into binding system to enhance strength, stress-strain behavior of products and structures. Maximal effect of reinforcing process is possible when optimal parameters (length and consumption of fibre are determined. Moreover one need to consider particle-size composition and hardening process of binding system. In this paper the critical length of natural and sinthesized fibres as well as minimally required content in cellular systems is calculated with the mathematical apparatus of structural topology. As an example the foam concrete based on cement-free nanostructured binder with basalt fibre and microreinforcing constructional polymeric fibre is studied. Fiber diameter, refined with microstructure analysis, accomplished by SEM-microscopy and experimentally determined packing density in loose and compact state are applied as input parameters. Measurement of the fibre topological characteristics with acceptable is accomplished according to material porosity and pore size. So the minimal effective fibre length taking into account homogeneous distribution in bulk of composite matrix is less of 1 mm; minimal fibre consumption is 0,2–0,5 (by wt. %. Irrational optimization leads to unreasonable cost growth of final materials as well as formation of balling inclusions that negatively affects on final performance of composite.
Reports of the working groups on precision calculations for LEP2 physics. Proceedings
Jadach, S.; Passarino, G.; Pittau, R.
2000-01-01
This is the report of the LEP2 Monte Carlo Workshop held at CERN from 1999 to 2000. It consists of four parts. In the first part, the most recent developments in the calculation of four-fermion processes in electron-positron collisions at LEP2 are presented, concentrating on predictions for four main reactions: W-pair production, visible photons in four-fermion events, single-W production, and Z-pair production. Based on a comparison of results within different approaches, theoretical uncertainties on these prediction are established. The second part is devoted to QCD issues, focusing on improving the understanding and the Monte Carlo simulation of multijet final states due to hard QCD processes at LEP, i.e. quark-antiquark plus multigluon and/or secondary quark production, with particular emphasis on four-jet final states and b-quark mass effects. Specific topics covered are: relevant developments in the main event generators; description and tuning of inclusive (all-flavour) jet rates; quark mass effects in the three- and four-jet rates; mass, higher-order and hadronization effects in four-jet angular and shape distributions; b-quark fragmentation and gluon splitting into b-quarks. In the third part, γγ physics is discussed. After a detailed description of the physics modelling of the most recent versions of the currently available codes, comparisons between the results of the different event generators, as well as between LEP data and the theoretical predictions are presented, together with the problem of background due to γγ processes in searches for new particles. In the last part, recent developments in the theoretical calculation of two-fermion processes are reported. The Bhabha process and the production of muon, tau, neutrino and quark pairs is covered. On the basis of comparison of various calculations, theoretical uncertainties are estimated and compared with those needed for the final LEP2 data analysis. The subjects for further study are identified
Studying the physics potential of long-baseline experiments in terms of new sensitivity parameters
Singh, Mandip
2016-01-01
We investigate physics opportunities to constraint the leptonic CP-violation phase δ_C_P through numerical analysis of working neutrino oscillation probability parameters, in the context of long-baseline experiments. Numerical analysis of two parameters, the “transition probability δ_C_P phase sensitivity parameter (A"M)” and the “CP-violation probability δ_C_P phase sensitivity parameter (A"C"P),” as functions of beam energy and/or baseline have been carried out. It is an elegant technique to broadly analyze different experiments to constrain the δ_C_P phase and also to investigate the mass hierarchy in the leptonic sector. Positive and negative values of the parameter A"C"P, corresponding to either hierarchy in the specific beam energy ranges, could be a very promising way to explore the mass hierarchy and δ_C_P phase. The keys to more robust bounds on the δ_C_P phase are improvements of the involved detection techniques to explore lower energies and relatively long baseline regions with better experimental accuracy.
Reactor physics simulations with coupled Monte Carlo calculation and computational fluid dynamics
Seker, V.; Thomas, J. W.; Downar, T. J.
2007-01-01
The interest in high fidelity modeling of nuclear reactor cores has increased over the last few years and has become computationally more feasible because of the dramatic improvements in processor speed and the availability of low cost parallel platforms. In the research here high fidelity, multi-physics analyses was performed by solving the neutron transport equation using Monte Carlo methods and by solving the thermal-hydraulics equations using computational fluid dynamics. A computation tool based on coupling the Monte Carlo code MCNP5 and the Computational Fluid Dynamics (CFD) code STAR-CD was developed as an audit tool for lower order nuclear reactor calculations. This paper presents the methodology of the developed computer program 'McSTAR' along with the verification and validation efforts. McSTAR is written in PERL programming language and couples MCNP5 and the commercial CFD code STAR-CD. MCNP uses a continuous energy cross section library produced by the NJOY code system from the raw ENDF/B data. A major part of the work was to develop and implement methods to update the cross section library with the temperature distribution calculated by STAR-CD for every region. Three different methods were investigated and two of them are implemented in McSTAR. The user subroutines in STAR-CD are modified to read the power density data and assign them to the appropriate variables in the program and to write an output data file containing the temperature, density and indexing information to perform the mapping between MCNP and STAR-CD cells. The necessary input file manipulation, data file generation, normalization and multi-processor calculation settings are all done through the program flow in McSTAR. Initial testing of the code was performed using a single pin cell and a 3X3 PWR pin-cell problem. The preliminary results of the single pin-cell problem are compared with those obtained from a STAR-CD coupled calculation with the deterministic transport code De
Shen, W.
2004-01-01
A micro-depletion model has been developed and implemented in the *SIMULATE module of RFSP to use WIMS-calculated lattice properties in history-based local-parameter calculations. A comparison between the micro-depletion and WIMS results for each type of lattice cross section and for the infinite-lattice multiplication factor was also performed for a fuel similar to that which may be used in the ACR fuel. The comparison shows that the micro-depletion calculation agrees well with the WIMS-IST calculation. The relative differences in k-infinity are within ±0.5 mk and ±0.9 mk for perturbation and depletion calculations, respectively. The micro-depletion model gives the *SIMULATE module of RFSP the capability to use WIMS-calculated lattice properties in history-based local-parameter calculations without resorting to the Simple-Cell-Methodology (SCM) surrogate for CANDU core-tracking simulations. (author)
Boscá, A.; Pedrós, J.; Martínez, J.; Calle, F.
2015-01-01
Due to its intrinsic high mobility, graphene has proved to be a suitable material for high-speed electronics, where graphene field-effect transistor (GFET) has shown excellent properties. In this work, we present a method for extracting relevant electrical parameters from GFET devices using a simple electrical characterization and a model fitting. With experimental data from the device output characteristics, the method allows to calculate parameters such as the mobility, the contact resistance, and the fixed charge. Differentiated electron and hole mobilities and direct connection with intrinsic material properties are some of the key aspects of this method. Moreover, the method output values can be correlated with several issues during key fabrication steps such as the graphene growth and transfer, the lithographic steps, or the metalization processes, providing a flexible tool for quality control in GFET fabrication, as well as a valuable feedback for improving the material-growth process
Boscá, A., E-mail: alberto.bosca@upm.es [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Dpto. de Ingeniería Electrónica, E.T.S.I. de Telecomunicación, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Pedrós, J. [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Campus de Excelencia Internacional, Campus Moncloa UCM-UPM, Madrid 28040 (Spain); Martínez, J. [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Dpto. de Ciencia de Materiales, E.T.S.I de Caminos, Canales y Puertos, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Calle, F. [Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Dpto. de Ingeniería Electrónica, E.T.S.I. de Telecomunicación, Universidad Politécnica de Madrid, Madrid 28040 (Spain); Campus de Excelencia Internacional, Campus Moncloa UCM-UPM, Madrid 28040 (Spain)
2015-01-28
Due to its intrinsic high mobility, graphene has proved to be a suitable material for high-speed electronics, where graphene field-effect transistor (GFET) has shown excellent properties. In this work, we present a method for extracting relevant electrical parameters from GFET devices using a simple electrical characterization and a model fitting. With experimental data from the device output characteristics, the method allows to calculate parameters such as the mobility, the contact resistance, and the fixed charge. Differentiated electron and hole mobilities and direct connection with intrinsic material properties are some of the key aspects of this method. Moreover, the method output values can be correlated with several issues during key fabrication steps such as the graphene growth and transfer, the lithographic steps, or the metalization processes, providing a flexible tool for quality control in GFET fabrication, as well as a valuable feedback for improving the material-growth process.
Kucharczyk, M.; Olszewski, S.
1982-01-01
The Grueneisen parameter of alkali halides is calculated by an ab initio quantum-statistical method and then compared with the experimental data. The crystal model applied assumes the crystal ions to be compressible but impenetrable spheres. The ions are described with the aid of a modified Thomas-Fermi theory with exchange. At the next step it is possible to calculate the energy needed to transform the system of the non-interacting ions into the ionic system represented by the crystal lattice. This calculation allows for an ab initio estimate of the parameters entering the Born, or the Born-Mayer, repulsive part of the crystal energy. The parameters are then used in the calculation of the Grueneisen parameter and its dependence on the crystal compression. (author)
Ridzikova, A; Fronka, A.; Maly, B.; Moucka, L.
2003-01-01
In the present investigation, we will be study the dose relevant factors from continual monitoring in real homes into account getting more accurate estimation of 222 Rn the effective dose. The dose relevant parameters include the radon concentration, the equilibrium factor (f), the fraction (fp) of unattached radon decay products and real time occupancy people in home. The result of the measurement are the time courses of radon concentration that are based on estimation effective doses together with assessment of the real time occupancy people indoor. We found out by analysis that year effective dose is lower than effective dose estimated by ICRP recommendation from the integral measurement that included only average radon concentration. Our analysis of estimation effective doses using measurement of several physical parameters was made only in one case and for the better specification is important to measure in different real occupancy houses. (authors)
A critical experimental study of integral physics parameters in simulated LMFBR meltdown cores
Bhattacharyya, S.K.; Wade, D.C.; Bucher, R.G.; Smith, D.M.; McKnight, R.D.; Lesage, L.G.
1978-01-01
Integral physics parameters of several representative, idealized meltdown LMFBR configurations were measured in mockup critical assemblies on the ZPR-9 reactor at Argonne National Laboratory. The experiments were designed to provide data for the validation of analytical methods used in the neutronics part of LMFBR accident analysis. Large core distortions were introduced in these experiments (involving 18.5% core volume) and the reactivity worths of configuration changes were determined. The neutronics parameters measured in the various configurations showed large changes upon core distortion. Both diffusion theory and transport theory methods were shown to mispredict the experimental configuration eigenvalues. In addition, diffusion theory methods were shown to result in a non-conservative misprediction of the experimental configuration change worths. (author)
Dosimetry-adjusted reactor physics parameters for pressure vessel neutron exposure assessment
McElroy, W.N.; Kellogg, L.S.
1988-01-01
The ASTM E706 master matrix standard describes a series of 20 American Society for Testing and Materials (ASTM) standard practices, guides, and methods for use in the prediction of neutron-induced changes in light water reactor (LWR) pressure vessel (PV) and support structure steels throughout a PV's service life. Some of these are existing ASTM standards, some are ASTM standards that have been modified, and some are new ASTM standards. These standards are periodically revised to assume their applicability during the 40-yr (32 effective full-power years) design license period for a nuclear power plant. They are now under review by two new ASTM plant life extension task groups: E10.05.11 on physics dosimetry and E10.02.11 on metallurgy. A brief review on the current application of these standards and a discussion of the status of work to verify the accuracy of derived physics-dosimetry parameter values is presented in this paper
Estimating Parameters in Physical Models through Bayesian Inversion: A Complete Example
Allmaras, Moritz
2013-02-07
All mathematical models of real-world phenomena contain parameters that need to be estimated from measurements, either for realistic predictions or simply to understand the characteristics of the model. Bayesian statistics provides a framework for parameter estimation in which uncertainties about models and measurements are translated into uncertainties in estimates of parameters. This paper provides a simple, step-by-step example-starting from a physical experiment and going through all of the mathematics-to explain the use of Bayesian techniques for estimating the coefficients of gravity and air friction in the equations describing a falling body. In the experiment we dropped an object from a known height and recorded the free fall using a video camera. The video recording was analyzed frame by frame to obtain the distance the body had fallen as a function of time, including measures of uncertainty in our data that we describe as probability densities. We explain the decisions behind the various choices of probability distributions and relate them to observed phenomena. Our measured data are then combined with a mathematical model of a falling body to obtain probability densities on the space of parameters we seek to estimate. We interpret these results and discuss sources of errors in our estimation procedure. © 2013 Society for Industrial and Applied Mathematics.
Neeman, Elias M.; Dréan, Pascal; Huet, T. R.
2016-06-01
The emission of volatile organic compounds, from plants has strong revelance for plant physiology, plant ecology and atmospheric chemistry. Camphene (C10H16) is a bicyclic monoterpene which is emitted in the atmosphere by biogenic sources. The structure of the unique stable conformer was optimized using density functional theory and ab initio calculations. The rotational spectrum of camphene was recorded in a supersonic jet expansion with a Fourier transform microwave spectrometer over the range 2-20 GHz. Signals from the parent species and from the ten 13C isotopomers were observed in natural abundance. The rotational and centrifugal distortion parameters were fitted to a Watson's Hamiltonian in the A-reduction. A magnetic hyperfine structure associated with the pairs of hydrogen nuclei in the methylene groups was observed and modeled.The rotational constants coupled to the equilibrium structure calculations were used to determine the r_0 and the r_m(1) gas-phase geometries of the carbon skeleton. The present work provides the first spectroscopic characterization of camphene in the gas phase and these results are also relevant for ozonolysis kinetics study through Criegee intermediates. R. Baraldi, F. Rapparini, O. Facini, D. Spano and P. Duce, Journal of Mediterranean Ecology, Vol.6, No.1, (2005). A. Bracho-Nunez, N. M. Knothe, S. Welter, M. Staudt, W. R. Costa, M. A. R. Liberato, M. T. F. Piedade, and J. Kesselmeier Biogeosciences, 10, 5855-5873, (2013). Minna Kivimäenpää, Narantsetseg Magsarjav, Rajendra Ghimire, Juha-Matti Markkanen, Juha Heijari, Martti Vuorinen and Jarmo K. Holopainen, Atmospheric Environment, 60, 477-485, (2012). R.C. de M. Oliveira and G. F. Bauerfeldt, J. Phys. Chem. A, 119 2802-2812 (2015)
Hsieh, Po-Fan; Wang, Yu-De; Huang, Chi-Ping; Wu, Hsi-Chin; Yang, Che-Rei; Chen, Guang-Heng; Chang, Chao-Hsiang
2016-07-01
We proposed a mathematical formula to calculate contact surface area between a tumor and renal parenchyma. We examined the applicability of using contact surface area to predict renal function after partial nephrectomy. We performed this retrospective study in patients who underwent partial nephrectomy between January 2012 and December 2014. Based on abdominopelvic computerized tomography or magnetic resonance imaging, we calculated the contact surface area using the formula (2*π*radius*depth) developed by integral calculus. We then evaluated the correlation between contact surface area and perioperative parameters, and compared contact surface area and R.E.N.A.L. (Radius/Exophytic/endophytic/Nearness to collecting system/Anterior/Location) score in predicting a reduction in renal function. Overall 35, 26 and 45 patients underwent partial nephrectomy with open, laparoscopic and robotic approaches, respectively. Mean ± SD contact surface area was 30.7±26.1 cm(2) and median (IQR) R.E.N.A.L. score was 7 (2.25). Spearman correlation analysis showed that contact surface area was significantly associated with estimated blood loss (p=0.04), operative time (p=0.04) and percent change in estimated glomerular filtration rate (p contact surface area and R.E.N.A.L. score independently affected percent change in estimated glomerular filtration rate (p contact surface area was a better independent predictor of a greater than 10% change in estimated glomerular filtration rate compared to R.E.N.A.L. score (AUC 0.86 vs 0.69). Using this simple mathematical method, contact surface area was associated with surgical outcomes. Compared to R.E.N.A.L. score, contact surface area was a better predictor of functional change after partial nephrectomy. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Bertoldi, Dalía S.; Ramos, Susana B.; Guillermet, Armando Fernández
2017-08-01
We present a theoretical analysis of the equation of state (EOS) of metals using a quasi-harmonic Einstein model with a dimensionless cohesive energy versus distance function (F(z)) involving the Wigner-Seitz radius and a material-dependent scaling length, as suggested in classical works by Rose, Ferrante, Smith and collaborators. Using this model, and "universal" values for the function and its first and second derivatives at the equilibrium distance (z=0), three general interrelations between EOS parameters and the cohesive energy are obtained. The first correlation involves the bulk modulus, and the second, the thermal expansion coefficient. In order to test these results an extensive database is developed, which involves available experimental data, and results of current ab initio density-functional-theory calculations using the VASP code. In particular, the 0 K values for volume, bulk modulus, its pressure derivative, and the cohesive energy of 27 elements belonging to the first (Sc, Ti, V, Cr, Fe, Co, Ni, Cu, Zn), second (Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd) and third (Hf, Ta, W, Re, Os, Ir, Pt, Au) transition row of the Periodic Table are calculated ab initio and used to test the present results. The third correlation obtained, allows an evaluation of the third derivative of F(z) at z=0 for the current elements. With this new information, a discussion is presented of the possibility of finding a "universal" F(z) versus z function able to account accurately for the pressure derivative of the bulk modulus of the transition elements.
Relating auditory attributes of multichannel sound to preference and to physical parameters
Choisel, Sylvain; Wickelmaier, Florian Maria
2006-01-01
playing a role in sound quality evaluation. Eight selected attributes are quantified by a panel of 39 listeners using paired-comparison judgments and probabilistic choice models, and related to overall preference. A multiple-regression model predicts preference well, and some similarities are observed......Sound reproduced by multichannel systems is affected by many factors giving rise to various sensations, or auditory attributes. Relating specific attributes to overall preference and to physical measures of the sound field provides valuable information for a better understanding of the parameters...
Methane spectral line widths and shifts, and dependences on physical parameters
Fox, K.; Quillen, D. T.; Jennings, D. E.; Wagner, J.; Plymate, C.
1991-01-01
A detailed report of the recent high-resolution spectroscopic research on widths and shifts measured for a strong infrared-active fundamental of methane is presented. They were measured in collision with several rare gases and diatomic molecules, in the vibrational-rotational fundamental near 3000/cm. These measurements were made at an ambient temperature of 294 K over a range of pressures from 100 to 700 torr. The measurements are discussed in a preliminary but detailed and quantitative manner with reference to masses, polarizabilities, and quadrupole moments. Some functional dependences on these physical parameters are considered. The present data are useful for studies of corresponding planetary spectra.
A method to measure the thermal-physical parameter of gas hydrate in porous media
Diao, S.B.; Ye, Y.G.; Yue, Y.J.; Zhang, J.; Chen, Q.; Hu, G.W. [Qingdao Inst. of Marine Geology, Qingdao (China)
2008-07-01
It is important to explore and make good use of gas hydrates through the examination of the thermal-physical parameters of sediment. This paper presented a new type of simulation experiment using a device that was designed based on the theories of time domain reflection and transient hot wire method. A series of investigations were performed using this new device. The paper described the experiment, with reference to the experiment device and materials and method. It also presented the results of thermal physical properties; result of the thermal conductivity of water, dry sand and wet sand; and results of wet sand under various pressures. The time domain reflection (TDR) method was utilized to monitor the saturation of the hydrates. Both parallel hot-wire method and cross hot-wire method were utilized to measure the thermal conductivity of the gas hydrate in porous media. A TDR sensor which was equipped with both cross hot-wire probe and parallel hot-wire probe was developed in order to measure the cell temperature with these two methods at one time. It was concluded that the TDR probe could be taken as an online measurement skill in investigating the hydrate thermal physical property in porous media. The TDR sensor could monitor the hydrate formation process and the parallel hot-wire method and cross hot-wire method could effectively measure the thermal physical properties of the hydrates in porous media. 10 refs., 7 figs.
Ranković Goran
2012-01-01
Full Text Available Bacground/Aim. Regular physical activity is widely accepted as factor that reduces all-cause mortality and improves a number of health outcomes. The aim of this study was to investigate the effects of aerobic exercise training on cardiovascular parameters, lipid profile and endothelial function in patients with stable coronary artery disease (CAD. Methods. The study included seventy patients with stable CAD. All the patients were divided into two groups: the group I - 33 patients with CAD and with regular aerobic physical training during cardiovascular rehabilitation program phase II for 3 weeks in our rehabilitation center and 3 weeks after that in their home setting, and the group II (control - 37 patients with CAD and sedentary lifestyle. Exercise training consisted of continual aerobic exercise for 45 minutes on a treadmill, room bicycle or walking, three times a week. We determined lipid and cardiovascular parameters and nitric oxide (NO concentration at the beginning and after a six-week of training. Results. There were no significant differences in body weight, waist circumference and waist/hip ratio at the start and at the end of physical training program. Physical training significantly reduced body mass index after six weeks compared to the initial and control values. Physical training significantly reduced systolic and diastolic blood pressure and heart rate after a six-week training period (p < 0.05. Heart rate was significantly lower after a training period as compared to the control (p < 0.05. A significant reduction of triglyceride and increased high density lipoprotein cholesterol (HDL-C concentration after cardiovascular rehabilitation were registered (p < 0.05. The concentration of triglycerides was significantly lower while NO and HDL-C were higher after six weeks in the exercise training group (p < 0.05. Conclusion. Dynamic training can improve blood pressure in patients with moderate to severe hypertension and reduce the
Molina-Trinidad, E.M.; Arteaga de Murphy, C.; Jung-Cook, H.
2004-01-01
Good manufacturing practices specify that a well-type scintillation NaI(Tl) crystal detector has to be validated in order to detect radioactivity from any radiopharmaceutical used to obtain radiopharmacokinetic parameters. A 5 cm well-type NaI(Tl) scintillation detector was coupled to a multi-channel analyzer centered at the 140 keV 99m Tc peak with a 20% window. The area represents counts per minute (cpm). All the net cpm were decay corrected. The activity source was 99m Tc-glucarate developed as an imaging agent for acute myocardial infarction. Wistar rats were injected in a tail vein with 0.1 ml (3.7 MBq) of 99m Tc-glucarate solution and 13 blood samples were taken. The cpm were the input data for the WINNONLN program which calculates radiopharmacokinetic parameters. The detector's efficiency for 99m Tc was 15.03% and the sensitivity 1.12 kBq/ml in plasma. The response was linear between 0.31-14.3 kBq/ml of 99m Tc-glucarate. The maximum assay variation coefficient was 2.79 and recovery of 99m Tc-glucarate in plasma was 99.8% ± 0.2%. LOD was 0.31 kBq and LOQ 1.12 kBq in plasma samples. 99m Tc-glucarate follows a two-compartment model of distribution with Vd of 21.74 ml ± 2.71 ml; a Vdss of 74.36 ml ± 12.67 ml; t 1/2α 0.74 h ± 0.19 h; t 1/2β 18.98 h ± 4.36 h; AUC = 32.75 μCi/min x ml ± 3.73 μCi/min x ml; MRT 24.35 h ± 5.51 h and total clearance 3.05 ml/h ±0.35 ml/h. The well-type detector fulfills the quality system requirements and the radiopharmacokinetic parameters for 99m Tc-glucarate in rats are reliable. (author)
Anderson, Christian Carl
This Dissertation explores the physics underlying the propagation of ultrasonic waves in bone and in heart tissue through the use of Bayesian probability theory. Quantitative ultrasound is a noninvasive modality used for clinical detection, characterization, and evaluation of bone quality and cardiovascular disease. Approaches that extend the state of knowledge of the physics underpinning the interaction of ultrasound with inherently inhomogeneous and isotropic tissue have the potential to enhance its clinical utility. Simulations of fast and slow compressional wave propagation in cancellous bone were carried out to demonstrate the plausibility of a proposed explanation for the widely reported anomalous negative dispersion in cancellous bone. The results showed that negative dispersion could arise from analysis that proceeded under the assumption that the data consist of only a single ultrasonic wave, when in fact two overlapping and interfering waves are present. The confounding effect of overlapping fast and slow waves was addressed by applying Bayesian parameter estimation to simulated data, to experimental data acquired on bone-mimicking phantoms, and to data acquired in vitro on cancellous bone. The Bayesian approach successfully estimated the properties of the individual fast and slow waves even when they strongly overlapped in the acquired data. The Bayesian parameter estimation technique was further applied to an investigation of the anisotropy of ultrasonic properties in cancellous bone. The degree to which fast and slow waves overlap is partially determined by the angle of insonation of ultrasound relative to the predominant direction of trabecular orientation. In the past, studies of anisotropy have been limited by interference between fast and slow waves over a portion of the range of insonation angles. Bayesian analysis estimated attenuation, velocity, and amplitude parameters over the entire range of insonation angles, allowing a more complete
Snyder, H.; Leva-Lopez, J.
2017-12-01
During the late Campanian age in North America fluvial systems drained the highlands of the Sevier orogenic belt and travelled east towards the Western Interior Seaway. One of such systems deposited the Canyon Creek Member (CCM) of the Ericson Formation in south-western Wyoming. At this time the fluvial system was being partially controlled by laterally variable subsidence caused by incipient Laramide uplifts. These uplifts rather than real topographic features were only areas of reduced subsidence at the time of deposition of the CCM. Surface expression at that time must have been minimum, only minute changes in slope and accommodation. Outcrops around these Laramide structures, in particular both flanks of the Rock Springs Uplift, the western side of the Rawlins uplift and the north flank of the Uinta Mountains, have been sampled to study the petrography, grain size, roundness and sorting of the CCM, which along with the cross-bed thickness and bar thickness allowed calculation of the hydraulic parameters of the rivers that deposited the CCM. This study reveals how the fluvial system evolved and responded to the very small changes in subsidence and slope. Furthermore, the petrography will shed light on the provenance of these sandstones and on the relative importance of Sevier sources versus Laramide sources. This work is framed in a larger study that shows how incipient Laramide structural highs modified the behavior, style and architecture of the fluvial system, affecting its thickness, facies characteristics and net-to-gross both down-dip and along strike across the basin.
Monitoring soil chemical and physical parameters under Douglas fir in the Netherlands
Konsten, C.J.M.; Tiktak, A.; Bouten, W.
1987-01-01
In march 1987 a monitoring program started in two Douglas fir stands of different vitality in the Netherlands. Aim of the study is to provide insight in the chemical and physical rooting conditions of the vegetation and to quantify the contributions of atmospheric deposition to soil acidification. The hydrological part of the monitoring progam consists of automated measurements of precipitation, throughfall, soil water pressure head and soil water content; in addition soil water content is determined by neutron sonde measurements and gravimetry. These data are used as input data for simulation models which calculate water fluxes through the vegetation and soil. For the soil chemical part of the program precipitation (bulk and wet-only), throughfall and litter fall are sampled. The soil solution is sampled by suction from porous cups and from porous plates by a new, continous technique. Combination of soil chemical and soil physical data will result in chemical fluxes through the vegetation and through various soil compartments. Element budgets for the ecosystem will also be calculated. The program forms part of an interdisciplinary monitoring project within the Dutch Priority Programme on Acidification. 2 figs., 1 tab., 19 refs.
Iurciuc, Stela; Avram, Claudiu; Turi, Vladiana; Militaru, Anda; Avram, Adina; Cimpean, Anca Maria; Iurciuc, Mircea
2016-01-01
To evaluate the impact of physical training on central hemodynamic parameters and elasticity of large arteries in hypertensive patients. A total of 129 hypertensive patients were divided into two groups: group A followed lifestyle changes and physical training; and group B acted as a control group; seven parameters were recorded: Pulse wave velocity (PWVao), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), central aortic systolic blood pressure (SBPao), aortic diastolic blood pressure (DBPao), and central aortic pulse pressure (PPao). The difference between values at 4 months and baseline (Δ) were as follows: ΔPWVao was -1.02 m/s (p<0.001) versus 0.17 m/s (p=0.035), ΔSBPao was -9.6 mmHg (p=0.009) versus 1.6 mmHg (p=0.064), and ΔPPao was -6.8 mmHg (p<0.001) versus 3.2 mmHg, (p=0.029) in group A versus B, respectively. Exercise training improves SBP, PP, SBPao, PPao and may delay arterial ageing. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
Vanessa Drieli Seron Antonini
2014-12-01
Full Text Available OBJECTIVE: To compare body composition, hemodynamic parameters, health-related physical fitness, and health-related quality of life of adolescents with anthropometric diagnosis of overweight, obesity, and severe obesity.METHODS: 220 adolescents with excess body weight were enrolled. They were beginners in a intervention program that included patients based on age, availability, presence of excess body weight, place of residence, and agreement to participate in the study. This study collected anthropometric and hemodynamic variables, health-related physical fitness, and health-related quality of life of the adolescents. To compare the three groups according to nutritional status, parametric and non-parametric tests were applied. Significance level was set at p0.05. Body weight, body mass index, waist and hip circumference, and systolic blood pressure increased as degree of excess weightincreased (p<0.05. Dyastolic blood pressure of the severe obesity group was higher than the other groups (p<0.05. There was an association between the degree of excess weight and the prevalence of altered blood pressure (overweight: 12.1%; obesity: 28.1%; severe obesity: 45.5%; p<0.001. The results were similar when genders were analyzed separately.CONCLUSION: Results suggest that overweight adolescents presented similar results compared to obese and severely obese adolescents in most of the parameters analyzed.
Kruse, Natalie A; DeRose, Lisa; Korenowsky, Rebekah; Bowman, Jennifer R; Lopez, Dina; Johnson, Kelly; Rankin, Edward
2013-10-15
Acid mine drainage (AMD) negatively impacts not only stream chemistry, but also aquatic biology. The ultimate goal of AMD treatment is restoration of the biological community, but that goal is rarely explicit in treatment system design. Hewett Fork in Raccoon Creek Watershed, Ohio, has been impacted by historic coal mining and has been treated with a calcium oxide doser in the headwaters of the watershed since 2004. All of the acidic inputs are isolated to a 1.5 km stretch of stream in the headwaters of the Hewett Fork watershed. The macroinvertebrate and fish communities have begun to recover and it is possible to distinguish three zones downstream of the doser: an impaired zone, a transition zone and a recovered zone. Alkalinity from both the doser and natural sources and physical stream parameters play a role in stream restoration. In Hewett Fork, natural alkaline additions downstream are higher than those from the doser. Both, alkaline additions and stream velocity drive sediment and metal deposition. Metal deposition occurs in several patterns; aluminum tends to deposit in regions of low stream velocity, while iron tends to deposit once sufficient alkalinity is added to the system downstream of mining inputs. The majority of metal deposition occurs upstream of the recovered zone. Both the physical stream parameters and natural alkalinity sources influence biological recovery in treated AMD streams and should be considered in remediation plans. Copyright © 2013 Elsevier Ltd. All rights reserved.
Nguyen, Q.H.
1994-01-01
This report documents the search strategies and results for available technologies and developers to develop tank waste depth profiling/physical parameter sensors. Sources searched include worldwide research reports, technical papers, journals, private industries, and work at Westinghouse Hanford Company (WHC) at Richland site. Tank waste physical parameters of interest are: abrasiveness, compressive strength, corrosiveness, density, pH, particle size/shape, porosity, radiation, settling velocity, shear strength, shear wave velocity, tensile strength, temperature, viscosity, and viscoelasticity. A list of related articles or sources for each physical parameters is provided
Nguyen, Q.H.
1994-09-12
This report documents the search strategies and results for available technologies and developers to develop tank waste depth profiling/physical parameter sensors. Sources searched include worldwide research reports, technical papers, journals, private industries, and work at Westinghouse Hanford Company (WHC) at Richland site. Tank waste physical parameters of interest are: abrasiveness, compressive strength, corrosiveness, density, pH, particle size/shape, porosity, radiation, settling velocity, shear strength, shear wave velocity, tensile strength, temperature, viscosity, and viscoelasticity. A list of related articles or sources for each physical parameters is provided.
Determination of Eros Physical Parameters for Near Earth Asteroid Rendezvous Orbit Phase Navigation
Miller, J. K.; Antreasian, P. J.; Georgini, J.; Owen, W. M.; Williams, B. G.; Yeomans, D. K.
1995-01-01
Navigation of the orbit phase of the Near Earth steroid Rendezvous (NEAR) mission will re,quire determination of certain physical parameters describing the size, shape, gravity field, attitude and inertial properties of Eros. Prior to launch, little was known about Eros except for its orbit which could be determined with high precision from ground based telescope observations. Radar bounce and light curve data provided a rough estimate of Eros shape and a fairly good estimate of the pole, prime meridian and spin rate. However, the determination of the NEAR spacecraft orbit requires a high precision model of Eros's physical parameters and the ground based data provides only marginal a priori information. Eros is the principal source of perturbations of the spacecraft's trajectory and the principal source of data for determining the orbit. The initial orbit determination strategy is therefore concerned with developing a precise model of Eros. The original plan for Eros orbital operations was to execute a series of rendezvous burns beginning on December 20,1998 and insert into a close Eros orbit in January 1999. As a result of an unplanned termination of the rendezvous burn on December 20, 1998, the NEAR spacecraft continued on its high velocity approach trajectory and passed within 3900 km of Eros on December 23, 1998. The planned rendezvous burn was delayed until January 3, 1999 which resulted in the spacecraft being placed on a trajectory that slowly returns to Eros with a subsequent delay of close Eros orbital operations until February 2001. The flyby of Eros provided a brief glimpse and allowed for a crude estimate of the pole, prime meridian and mass of Eros. More importantly for navigation, orbit determination software was executed in the landmark tracking mode to determine the spacecraft orbit and a preliminary shape and landmark data base has been obtained. The flyby also provided an opportunity to test orbit determination operational procedures that will be
Bayo, A.; Rodrigo, C.; Barrado, D.; Allard, F.
One of the very first steps astronomers working in stellar physics perform to advance in their studies, is to determine the most common/relevant physical parameters of the objects of study (effective temperature, bolometric luminosity, surface gravity, etc.). Different methodologies exist depending on the nature of the data, intrinsic properties of the objects, etc. One common approach is to compare the observational data with theoretical models passed through some simulator that will leave in the synthetic data the same imprint than the observational data carries, and see what set of parameters reproduce the observations best. Even in this case, depending on the kind of data the astronomer has, the methodology changes slightly. After parameters are published, the community tend to quote, praise and criticize them, sometimes paying little attention on whether the possible discrepancies come from the theoretical models, the data themselves or just the methodology used in the analysis. In this work we perform the simple, yet interesting, exercise of comparing the effective temperatures obtained via SED and more detailed spectral fittings (to the same grid of models), of a sample of well known and characterized young M-type objects members to different star forming regions and show how differences in temperature of up to 350 K can be expected just from the difference in methodology/data used. On the other hand we show how these differences are smaller for colder objects even when the complexity of the fit increases like for example introducing differential extinction. To perform this exercise we benefit greatly from the framework offered by the Virtual Observaotry.
Determination of new electroweak parameters at the ILC. Sensitivity to new physics
Beyer, M.; Schmidt, E.; Schroeder, H. [Rostock Univ. (Germany). Inst. fuer Physik; Kilian, W. [Siegen Univ. (Gesamthochschule) (Germany). Fach Physik]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Krstonosic, P.; Reuter, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Moenig, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2006-04-15
We present a study of the sensitivity of an International Linear Collider (ILC) to electroweak parameters in the absence of a light Higgs boson. In particular, we consider those parameters that have been inaccessible at previous colliders, quartic gauge couplings. Within a generic effective-field theory context we analyze all processes that contain quasi-elastic weak-boson scattering, using complete six-fermion matrix elements in unweighted event samples, fast simulation of the ILC detector, and a multidimensional parameter fit of the set of anomalous couplings. The analysis does not rely on simplifying assumptions such as custodial symmetry or approximations such as the equivalence theorem. We supplement this by a similar new study of triple weak-boson production, which is sensitive to the same set of anomalous couplings. Including the known results on triple gauge couplings and oblique corrections, we thus quantitatively determine the indirect sensitivity of the ILC to new physics in the electroweak symmetry-breaking sector, conveniently parameterized by real or fictitious resonances in each accessible spin/isospin channel. (Orig.)
Measurements of Physical Parameters of White Dwarfs: A Test of the Mass–Radius Relation
Bédard, A.; Bergeron, P.; Fontaine, G., E-mail: bedard@astro.umontreal.ca, E-mail: bergeron@astro.umontreal.ca, E-mail: fontaine@astro.umontreal.ca [Département de Physique, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec H3C 3J7 (Canada)
2017-10-10
We present a detailed spectroscopic and photometric analysis of 219 DA and DB white dwarfs for which trigonometric parallax measurements are available. Our aim is to compare the physical parameters derived from the spectroscopic and photometric techniques, and then to test the theoretical mass–radius relation for white dwarfs using these results. The agreement between spectroscopic and photometric parameters is found to be excellent, especially for effective temperatures, showing that our model atmospheres and fitting procedures provide an accurate, internally consistent analysis. The values of surface gravity and solid angle obtained, respectively, from spectroscopy and photometry, are combined with parallax measurements in various ways to study the validity of the mass–radius relation from an empirical point of view. After a thorough examination of our results, we find that 73% and 92% of the white dwarfs are consistent within 1 σ and 2 σ confidence levels, respectively, with the predictions of the mass–radius relation, thus providing strong support to the theory of stellar degeneracy. Our analysis also allows us to identify 15 stars that are better interpreted in terms of unresolved double degenerate binaries. Atmospheric parameters for both components in these binary systems are obtained using a novel approach. We further identify a few white dwarfs that are possibly composed of an iron core rather than a carbon/oxygen core, since they are consistent with Fe-core evolutionary models.
Evaluation of Physic-chemical Parameters of Water Quality on Agricultural Fields of Western Bahia
Enoc Lima do Rego
2017-06-01
Full Text Available For the diagnosis of the quality of water it is necessary to execute a set of analyzes (physical and chemical of the body of water that will provide information that integrate biotic and abiotic factors that govern the functioning of the ecosystem. The objective of this study is to evaluate the quality of water from wells and rivers of Urucuia aquifer region for investigation of contamination or contamination risks. Were realize collections in nine (9 areas of western Bahia, which were collect in each area, two points of well water samples and a river, and determining the electrical conductivity, pH, dissolved ions and metals. The results were compare with the maximum permissible values (MPV for human consumption by Ordinance No. 2914/11 of the Ministry of Health and National Environment Counsel - CONAMA (Resolution 357 and supplementary resolutions. The quantitative results of the analysis showed that the surface and well waters that are part of the aquifer Urucuia within the parameters investigated are below the values recommended by the legislation showing that the agricultural activities in the region has not affected to the evaluated parameters, the quality of water for human consumption. However, it is necessary a monitoring of surface and groundwater in the region with expansion parameters evaluated. DOI: http://dx.doi.org/10.17807/orbital.v9i2.880
Determination of new electroweak parameters at the ILC. Sensitivity to new physics
Beyer, M.; Schmidt, E.; Schroeder, H.; Krstonosic, P.; Reuter, J.; Moenig, K.
2006-04-01
We present a study of the sensitivity of an International Linear Collider (ILC) to electroweak parameters in the absence of a light Higgs boson. In particular, we consider those parameters that have been inaccessible at previous colliders, quartic gauge couplings. Within a generic effective-field theory context we analyze all processes that contain quasi-elastic weak-boson scattering, using complete six-fermion matrix elements in unweighted event samples, fast simulation of the ILC detector, and a multidimensional parameter fit of the set of anomalous couplings. The analysis does not rely on simplifying assumptions such as custodial symmetry or approximations such as the equivalence theorem. We supplement this by a similar new study of triple weak-boson production, which is sensitive to the same set of anomalous couplings. Including the known results on triple gauge couplings and oblique corrections, we thus quantitatively determine the indirect sensitivity of the ILC to new physics in the electroweak symmetry-breaking sector, conveniently parameterized by real or fictitious resonances in each accessible spin/isospin channel. (Orig.)
Aquatic environmental assessment of Lake Balaton in the light of physical-chemical water parameters.
Sebestyén, Vitkor; Németh, József; Juzsakova, Tatjana; Domokos, Endre; Kovács, Zsófia; Rédey, Ákos
2017-11-01
One of the issues of the Hungarian Water Management Strategy is the improvement and upgrading of the water of Lake Balaton. The Water Framework Directive (WFD) specifies and sets forth the achievement of the good ecological status. However, the assessment of the water quality of the lake as a complex system requires a comprehensive monitoring and evaluation procedure. Measurements were carried out around the Lake Balaton at ten different locations/sites and 13 physical-chemical parameters were monitored at each measurement site.For the interpretation of the water chemistry parameters the Aquatic Environmental Assessment (AEA) method devised by authors was used for the water body of the Lake Balaton. The AEA method can be used for all types of the water bodies since it is flexible and using individual weighting procedure for the water chemistry parameters comprehensive information can be obtain. The AEA method was compared with existing EIA methods according to a predefined criterion system and proved to be the most suitable tool for evaluating the environmental impacts in our study.On the basis of the results it can be concluded that the status of the quality of studied area on the Lake Balaton can be categorized as proper quality (from the outcome of the ten measurement sites this conclusion was reached at seven sites).
Effect of long-term physical aging on the kinetic parameters in a common pharmaceutical drug: Flutab
Abu-Sehly, A.A.; Elabbar, A.A.
2011-01-01
Differential scanning calorimetry (DSC) measurements were performed to investigate the effects of long-term physical aging on kinetic parameters of the pharmaceutical drug (Flutab). Kinetics parameters such as activation energy (E) and fragility parameter (m) of the glass transition for aged and rejuvenated glasses were determined using different kinetic models. Evidence of variation of E with temperature is presented. It is shown in this work that natural storage of the drug introduced significant physical aging as indicated by changes in the glass transition temperature, activation energy and fragility parameter.
Krotov, A.D.; Son'ko, A.V.
2009-01-01
Calculation of neutron-physical properties and radiation protection of space power reactor was made by means of the MCNP code allowing simulation of neutron, γ- and electron transport by the Monte Carlo method in the systems with combined geometry. Universality of the MCNP code has been demonstrated both for the calculation of reactor-converter so for the optimization of radiation protection that allows to reserve a new level of complex simulation of SNPS [ru
Rina Mazzette
2012-10-01
Full Text Available In Sardinia, goat farming is a very important resource. Sarda and Maltese breed are reared mainly for milk production and for suckling kids meat, while meat from adult goats is undervalued. The use of adult goat meat to obtain ripened ham will contribute to safeguard the Sardinian goat supply chain. The aim of the present study was to characterize Sarda and Maltese goat dry ham in order to evaluate the quality of autochthonous goat breed meat. Chemical-physical characteristics were determined dur-ing the production stages, while the rheological and colour parameters and the composition of the goat ham were determined at the end of ripening. The pH evolution during processing were similar to other cured meat products, e.g. sheep hams, even though the values were high, especially in the products from Sarda breed. The aw value regularly decreased during processing. Colour parameters (L*, a*, b* in the hams from Maltese goat breed were significantly (P<0.05 higher than in those from Sarda. The Sarda goat ham showed a significantly lower percentage of moisture (42% vs 52%, an higher protein content (44.35% vs 34.19%, while no differences were pointed out in the total fat content. Among the ham rheological properties, hardness parameters showed higher levels (13850.22±7589.92 vs 11073.99±6481.31, respectively in Sarda and Maltese hams in comparison to similar products from pork and sheep, while adhesiveness value was lower. The results show that the quality parameters of goat ripened hams are affected mainly by the charac-teristics of the goat meat, in relation on the breed and the breeding system, and, less, by the traditional technology.
R.V. Zaitsev
2016-09-01
Full Text Available Purpose. To ensure maximum production of electric power by photovoltaic vacilities, in addition to using highly efficient photovoltaic modules equipped with solar radiation concentrators must use a highly effective power take-off system. This paper is inscribed to solving the problem of a highly efficient and economic power take-off system development. Methodology. To solving the problem, we implemented three stages. On the first stage examines the dependence of electrical power from the intensity of the incident solar radiation. Based on this, the second stage is calculated the DC-DC converter resonant circuit and its working parameters, and developed circuit diagram of DC-DC converter. On the third stage, we carry out an analysis of power take-off system with step up DC-DC converter working. Results. In this paper, we carry out the analysis of working efficiency for photovoltaic facility power take-off system with step-up boost converter. The result of such analysis show that the efficiency of such system in a wide range of photovoltaic energy module illumination power is at 0.92, whereas the efficiency of classic power take-off systems does not exceed 0.70. Achieved results allow designing a circuit scheme of a controlled bridge resonant step-up converter with digital control. Proposed scheme will ensure reliable operation, fast and accurate location point of maximum power and conversion efficiency up to 0.96. Originality. Novelty of proposed power take-off system solution constitute in implementation of circuit with DC-DC converters, which as it shown by results of carrying out modeling is the most effective. Practical value. Practical implementation of proposed power take-off system design will allow reducing losses in connective wires and increasing the efficiency of such a system up to 92.5% in wide range of photovoltaic energy modules illumination.
Behzadi, Hadi; Manzetti, Sergio; Dargahi, Maryam; Roonasi, Payman; Khalilnia, Zahra
2018-01-01
In light of the importance of developing novel corrosion inhibitors, a series of quantum chemical calculations were carried out to evaluate 15N chemical shielding CS tensors as well as aromaticity indexes including NICS, HOMA, FLU, and PDI of three pyrazine derivatives, 2-methylpyrazine (MP), 2-aminopyrazine (AP) and 2-amino-5-bromopyrazine (ABP). The NICS parameters have been shown in previous studies to be paramount to the prediction of anti-corrosion properties, and have been combined here with HOMA, FLU and PDI and detailed wavefunction analysis to determine the effects from bromination and methylation on pyrazine. The results show that the electron density around the nitrogens, represented by CS tensors, can be good indicators of anti-corrosion efficiency. Additionally, the NICS, FLU and PDI, as aromaticity indicators of molecule, are well correlated with experimental corrosion inhibition efficiencies of the studied inhibitors. Bader sampling and detailed wavefunction analysis shows that the major effects from bromination on the pyrazine derivatives affect the Laplacian of the electron density of the ring, delocalizing the aromatic electrons of the carbon atoms into lone pairs and increasing polarization of the Laplacian values. This feature is well agreement with empirical studies, which show that ABP is the most efficient anti-corrosion compound followed by AP and MP, a property which can be attributed and predicted by derivation of the Laplacian of the electron density of the ring nuclei. This study shows the importance of devising DFT methods for development of new corrosion inhibitors, and the strength of electronic and nuclear analysis, and depicts most importantly how corrosion inhibitors composed of aromatic moieties may be modified to increase anti-corrosive properties.
Ryttov, Thomas A.; Shrock, Robert
2017-01-01
, adjoint, and symmetric rank-2 tensor representation are considered. We present scheme-independent calculations of the anomalous dimension $\\gamma_{\\bar\\psi\\psi,IR}$ to $O(\\Delta_f^4)$ and $\\beta'_{IR}$ to $O(\\Delta_f^5)$ at this IRFP, where $\\Delta_f$ is an $N_f$-dependent expansion parameter. Comparisons...... are made with conventional $n$-loop calculations and lattice measurements. As a test of the accuracy of the $\\Delta_f$ expansion, we calculate $\\gamma_{\\bar\\psi\\psi,IR}$ to $O(\\Delta_f^3)$ in ${\\cal N}=1$ SU($N_c$) supersymmetric quantum chromodynamics and find complete agreement, to this order...
Koenhen, D.M.; Smolders, C.A.
1975-01-01
Correlations of solvent solubility parameters with molar attraction constants and with properties like surface tension, dipole moment, and index of refraction have been explored. From relations found to be valid for solvents, it is possible to calculate the solubility parameters for polymers. A
Proskuryakov, K.N.; Bogomazov, D.N.; Poliakov, N. [Moscow Power Engineering Institute (Technical University), Moscow (Russian Federation)
2007-07-01
The new special module to neutron-physic and thermal-hydraulic computer codes for coolant acoustical characteristics calculation is worked out. The Russian computer code Rainbow has been selected for joint use with a developed module. This code system provides the possibility of EFOCP (Eigen Frequencies of Oscillations of the Coolant Pressure) calculations in any coolant acoustical elements of primary circuits of NPP. EFOCP values have been calculated for transient and for stationary operating. The calculated results for nominal operating were compared with results of measured EFOCP. For example, this comparison was provided for the system: 'pressurizer + surge line' of a WWER-1000 reactor. The calculated result 0.58 Hz practically coincides with the result of measurement (0.6 Hz). The EFOCP variations in transients are also shown. The presented results are intended to be useful for NPP vibration-acoustical certification. There are no serious difficulties for using this module with other computer codes.
Proskuryakov, K.N.; Bogomazov, D.N.; Poliakov, N.
2007-01-01
The new special module to neutron-physic and thermal-hydraulic computer codes for coolant acoustical characteristics calculation is worked out. The Russian computer code Rainbow has been selected for joint use with a developed module. This code system provides the possibility of EFOCP (Eigen Frequencies of Oscillations of the Coolant Pressure) calculations in any coolant acoustical elements of primary circuits of NPP. EFOCP values have been calculated for transient and for stationary operating. The calculated results for nominal operating were compared with results of measured EFOCP. For example, this comparison was provided for the system: 'pressurizer + surge line' of a WWER-1000 reactor. The calculated result 0.58 Hz practically coincides with the result of measurement (0.6 Hz). The EFOCP variations in transients are also shown. The presented results are intended to be useful for NPP vibration-acoustical certification. There are no serious difficulties for using this module with other computer codes
Wechsler, M.S.; Davidson, D.R.; Greenwood, L.R.; Sommer, W.F.
1984-01-01
CT: Differential and total displacement and helium production rates are calculated for copper irradiated by spallation neutrons and 760 MeV protons at the Clinton P. Anderson Los Alamos Meson Physics Facility (LAMPF). The calculations are performed using the SPECTER and VNMTC computer codes, the latter being specially designed for spallation radiation damage calculations. For comparison, similar SPECTER calculations are also described for irradiation of copper in EBR-II and RTNS-II. The results indicate substantial contributions to the displacement and helium production rates due to neutrons in the high-energy tail (above 20 MeV) of the LAMPF spallation neutron spectrum. Still higher production rates are calculated for irradiations in the direct proton beam. These results will provide useful background information for research to be conducted at a new irradiation facility at LAMPF
Study of gain variation as a function of physical parameters of GEM foil
Das, Supriya
2015-01-01
The ALICE experiment at LHC has planned to upgrade the TPC by replacing the MWPC with GEM based detecting elements to restrict the IBF to a tolerable value. However the variation of the gain as a function of physical parameters of industrially produced large size GEM foils is needed to be studied as a part of the QA procedure for the detector. The size of the electron avalanche and consequently the gain for GEM based detectors depend on the electric field distribution inside the holes. Geometry of a hole plays an important role in defining the electric field inside it. In this work we have studied the variation of the gain as a function of the hole diameters using Garfield++ simulation package.
Khan, M.S.; Zaheer-ud-Dln-Qureshi
2004-01-01
The Wah area historically famous for having sweet aquifer system is greatly effected due to environmental activities, such as industrialization and poor sewage system in the recent past. Thirty water samples have been collected from dug wells penetrating to shallow two layers in a multi layered aquifer system. The shallow aquifer is located at a depth of 45-85 feet and composed of very fine grained sand to silt in two layers separated by silty clay. To assess the contamination problems, physical parameters of groundwater such as temperature, color, turbidity, odour and taste have been estimated fifty percent of the dug wells have been found as contaminated and not fit for human consumption according 10 WHO standards. High values of electrical conductance determined in fifty percent of wells show trends of chemical contamination and their probable sources near by these wells against the general recharge pattern prevailing in the area can be located. (author)
Pruess, K.
1995-06-01
This paper examines the conceptualization of multiphase flow processes on the macroscale, as needed in field applications. It emphasizes that upscaling from the pore-level will in general not only introduce effective parameters but will also give rise to ''effective processes,'' i.e., the emergence of new physical effects that may not have a microscopic counterpart. ''Phase dispersion'' is discussed as an example of an effective process for the migration and remediation of non-aqueous phase liquid (NAPL) contaminants in heterogeneous media. An approximate space-and-time scaling invariance is derived for gravity-driven liquid flow in unsaturated two-dimensional porous media (fractures). Issues for future experimental and theoretical work are identified
Physically-Retrieving Cloud and Thermodynamic Parameters from Ultraspectral IR Measurements
Zhou, Daniel K.; Smith, William L., Sr.; Liu, Xu; Larar, Allen M.; Mango, Stephen A.; Huang, Hung-Lung
2007-01-01
A physical inversion scheme has been developed, dealing with cloudy as well as cloud-free radiance observed with ultraspectral infrared sounders, to simultaneously retrieve surface, atmospheric thermodynamic, and cloud microphysical parameters. A fast radiative transfer model, which applies to the clouded atmosphere, is used for atmospheric profile and cloud parameter retrieval. A one-dimensional (1-d) variational multi-variable inversion solution is used to improve an iterative background state defined by an eigenvector-regression-retrieval. The solution is iterated in order to account for non-linearity in the 1-d variational solution. It is shown that relatively accurate temperature and moisture retrievals can be achieved below optically thin clouds. For optically thick clouds, accurate temperature and moisture profiles down to cloud top level are obtained. For both optically thin and thick cloud situations, the cloud top height can be retrieved with relatively high accuracy (i.e., error < 1 km). NPOESS Airborne Sounder Testbed Interferometer (NAST-I) retrievals from the Atlantic-THORPEX Regional Campaign are compared with coincident observations obtained from dropsondes and the nadir-pointing Cloud Physics Lidar (CPL). This work was motivated by the need to obtain solutions for atmospheric soundings from infrared radiances observed for every individual field of view, regardless of cloud cover, from future ultraspectral geostationary satellite sounding instruments, such as the Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) and the Hyperspectral Environmental Suite (HES). However, this retrieval approach can also be applied to the ultraspectral sounding instruments to fly on Polar satellites, such as the Infrared Atmospheric Sounding Interferometer (IASI) on the European MetOp satellite, the Cross-track Infrared Sounder (CrIS) on the NPOESS Preparatory Project and the following NPOESS series of satellites.
DNA damage in lymphocytes induced by cardiac CT and comparison with physical exposure parameters
Fukumoto, Wataru; Tatsugami, Fuminari; Awai, Kazuo [Department of Diagnostic Radiology, Institute of Biomedical Health Sciences, Hiroshima University, Hiroshima (Japan); Ishida, Mari; Sakai, Chiemi [Institute of Biomedical and Health Sciences, Department of Cardiovascular Physiology and Medicine, Hiroshima University, Hiroshima (Japan); Tashiro, Satoshi [Hiroshima University, Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima (Japan); Ishida, Takafumi [Institute of Clinical Research West Medical Center, Hiroshima (Japan); Nakano, Yukiko [Hiroshima University Hospital, Department of Cardiovascular Medicine, Hiroshima (Japan)
2017-04-15
To investigate whether physical exposure parameters such as the dose index (CTDI), dose length product (DLP), and size-specific dose estimate (SSDE) are predictive of DNA damage. In vitro, we scanned a phantom containing blood samples from five volunteers at CTDI 50, 100, and 150 mGy. One sample was not scanned. We also scanned samples in three different-size phantoms at CTDI 100 mGy. In vivo, we enrolled 45 patients and obtained blood samples before and after cardiac CT. The γ-H2AX foci were counted. In vitro, in the control and at CTDI 50, 100, and 150 mGy, the number of γ-H2AX was 0.94 ± 0.24 (standard error, SE), 1.28 ± 0.30, 1.91 ± 0.47, and 2.16 ± 0.20. At SSDE 180, 156, and 135 mGy, it was 2.41 ± 0.20, 1.91 ± 0.47, and 1.42 ± 0.20 foci/cell. The γ-H2AX foci were positively correlated with the radiation dose and negatively correlated with the body size. In vivo, the γ-H2AX foci were significantly increased after CT (from 1.21 ± 0.19 to 1.92 ± 0.22 foci/cell) and correlated with CTDI, DLP, and SSDE. DNA damage was induced by cardiac CT. There was a correlation between the physical exposure parameters and γ-H2AX. (orig.)
Jürimäe, Jaak; Haljaste, Kaja; Cicchella, Antonio; Lätt, Evelin; Purge, Priit; Leppik, Aire; Jürimäe, Toivo
2007-02-01
The purpose of this study was to examine the influence of the energy cost of swimming, body composition, and technical parameters on swimming performance in young swimmers. Twenty-nine swimmers, 15 prepubertal (11.9 +/- 0.3 years; Tanner Stages 1-2) and 14 pubertal (14.3 +/- 1.4 years; Tanner Stages 3-4) boys participated in the study. The energy cost of swimming (Cs) and stroking parameters were assessed over maximal 400-m front-crawl swimming in a 25-m swimming pool. The backward extrapolation technique was used to evaluate peak oxygen consumption (VO2peak). A stroke index (SI; m2 . s(-1) . cycles(-1)) was calculated by multiplying the swimming speed by the stroke length. VO2peak results were compared with VO2peak test in the laboratory (bicycle, 2.86 +/- 0.74 L/min, vs. in water, 2.53 +/- 0.50 L/min; R2 = .713; p = .0001). Stepwise-regression analyses revealed that SI (R2 = .898), in-water VO2peak (R2 = .358), and arm span (R2 = .454) were the best predictors of swimming performance. The backward-extrapolation method could be used to assess VO2peak in young swimmers. SI, arm span, and VO2peak appear to be the major determinants of front-crawl swimming performance in young swimmers.
Study and optimization of thermo-physical parameters for a solar-still performance
Kaabi, A.; Zaidi, H.
2006-01-01
The thermo-physical parameters of a static solar still with a greenhouse effect were studied. The simulation was conducted for each component of the still at the same initial temperature and time step. Analyzed parameters included the solar collector; brine; absorber; and insulator. The thermophysical changes of different still components were analyzed as well as their impacts on the solar still's output. The aim of the study was to enhance distilled water production. A Gauss-Seidel iterative method was used to solve thermophysical equations. Results of the study showed that maximum hourly production of distilled water was reached at 13:00 PM, when temperatures differences between the brine and the inner side of the still had a significant impact on system productivity. Three types of material were tested: copper, aluminum, and steel. Copper gave improved production, higher thermal conductivity; higher heat, and an improved coefficient of absorption. Production of distilled water increased when a black layer of nickel was added to the still. It was concluded that solar still efficiency increased when the absorber had a high thermal conductivity and a high specific heat. 14 refs., 6 figs
Burton, B.
1984-01-01
Hot tensile (or compression) testing, where the stress developed in a material is measured under an imposed strain rate, is often used as an alternative to conventional creep testing. The advantages of the hot tensile test are that its duration can be more closely controlled by the experimenter and also that the technique is more convenient, since high precision testing machines are available. The main disadvantage is that the interpretation of results is more complex. The present paper relates the parameters which are measured in hot tensile tests, to physical processes which occur in materials deforming by a variety of mechanisms. For cases where no significant structural changes occur, as in viscous or superplastic flow, analytical expressions are derived which relate the stresses measured in these tests to material constants. When deformation is controlled by recovery processes, account has to be taken of the structural changes which occur concurrently. A wide variety of behaviour may then be exhibited which depends on the initial dislocation density, the presence of second-phase particles and the relative values of the recovery rate parameters and the velocity imposed by the testing machine. Numerical examples are provided for simple recovery models. (author)
Bhutwala, Krish; Beg, Farhat; Mariscal, Derek; Wilks, Scott; Ma, Tammy
2017-10-01
The Advanced Radiographic Capability (ARC) laser at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is the world's most energetic short-pulse laser. It comprises four beamlets, each of substantial energy ( 1.5 kJ), extended short-pulse duration (10-30 ps), and large focal spot (>=50% of energy in 150 µm spot). This allows ARC to achieve proton and light ion acceleration via the Target Normal Sheath Acceleration (TNSA) mechanism, but it is yet unknown how proton beam characteristics scale with ARC-regime laser parameters. As theory has also not yet been validated for laser-generated protons at ARC-regime laser parameters, we attempt to formulate the scaling physics of proton beam characteristics as a function of laser energy, intensity, focal spot size, pulse length, target geometry, etc. through a review of relevant proton acceleration experiments from laser facilities across the world. These predicted scaling laws should then guide target design and future diagnostics for desired proton beam experiments on the NIF ARC. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and funded by the LLNL LDRD program under tracking code 17-ERD-039.
Vranić, Edina; Uzunović, Alija
2008-01-01
Tablets are one of the most popular and preferred solid dosage forms because they can be accurately dosed, easily manufactured and packaged on a large scale, have good physical and chemical stability, and can contribute to good patient compliance given their ease of administration. The ability to match doses to patients depends on the availability of multiple dose sizes and adequate dose-response information. These are not always provided, so splitting of the tablets is sometimes necessary, Tablet splitting is an accepted practice in dispensing medication, It has been used when a dosage form of the required strength is not available commercially. The aim of our study was to compare some physical parameters of whole and scored lisinopril and lisinopril/hydrochlorthiazide tablets and to accept or exclude their influence on the obtaining of required dosage. According to the results obtained, we may conclude that tablets from batch “I” “IL “III” and “IV” satisfied pharmacopeial requirements concerning crushing strength, friability, disintegration time and mass uniformity. The hardness testing showed acceptable reproducibility and indicate that the data variation was primarily from the irreversible changes in the structure of tablet samples. The act of compacting powders stores energy within the tablets, by shifting or compressing the intermolecular bonds within the particles. The tablets have a natural tendency to relax once pressure is removed, and this tendency works against the interparticle bonding formed during compression. Hardness testing procedure causes irreversible changes in this structure. PMID:19125715
Sanchez Mazon, J.; Raba Diez, J. L.; Vazquez Rodriguez, J. A.; Pacheco Baldor, M. T.; Mendiguren Santiago, M. A.
2011-01-01
In the Protocol for the control treatment planning systems with ionizing radiation of the proposed SEFM tests to verify proper operation of the calculation in the evaluation of DVH (Dose Volume Histogram). The calculation of the volume that makes a planner may have important implications because it can trigger an overestimation of the dose or otherwise. We present a comparison of the calculation of volumes estimated with 4 different planners.
A Bayesian and Physics-Based Ground Motion Parameters Map Generation System
Ramirez-Guzman, L.; Quiroz, A.; Sandoval, H.; Perez-Yanez, C.; Ruiz, A. L.; Delgado, R.; Macias, M. A.; Alcántara, L.
2014-12-01
We present the Ground Motion Parameters Map Generation (GMPMG) system developed by the Institute of Engineering at the National Autonomous University of Mexico (UNAM). The system delivers estimates of information associated with the social impact of earthquakes, engineering ground motion parameters (gmp), and macroseismic intensity maps. The gmp calculated are peak ground acceleration and velocity (pga and pgv) and response spectral acceleration (SA). The GMPMG relies on real-time data received from strong ground motion stations belonging to UNAM's networks throughout Mexico. Data are gathered via satellite and internet service providers, and managed with the data acquisition software Earthworm. The system is self-contained and can perform all calculations required for estimating gmp and intensity maps due to earthquakes, automatically or manually. An initial data processing, by baseline correcting and removing records containing glitches or low signal-to-noise ratio, is performed. The system then assigns a hypocentral location using first arrivals and a simplified 3D model, followed by a moment tensor inversion, which is performed using a pre-calculated Receiver Green's Tensors (RGT) database for a realistic 3D model of Mexico. A backup system to compute epicentral location and magnitude is in place. A Bayesian Kriging is employed to combine recorded values with grids of computed gmp. The latter are obtained by using appropriate ground motion prediction equations (for pgv, pga and SA with T=0.3, 0.5, 1 and 1.5 s ) and numerical simulations performed in real time, using the aforementioned RGT database (for SA with T=2, 2.5 and 3 s). Estimated intensity maps are then computed using SA(T=2S) to Modified Mercalli Intensity correlations derived for central Mexico. The maps are made available to the institutions in charge of the disaster prevention systems. In order to analyze the accuracy of the maps, we compare them against observations not considered in the
Refractive Status at Birth: Its Relation to Newborn Physical Parameters at Birth and Gestational Age
Varghese, Raji Mathew; Sreenivas, Vishnubhatla; Puliyel, Jacob Mammen; Varughese, Sara
2009-01-01
Background Refractive status at birth is related to gestational age. Preterm babies have myopia which decreases as gestational age increases and term babies are known to be hypermetropic. This study looked at the correlation of refractive status with birth weight in term and preterm babies, and with physical indicators of intra-uterine growth such as the head circumference and length of the baby at birth. Methods All babies delivered at St. Stephens Hospital and admitted in the nursery were eligible for the study. Refraction was performed within the first week of life. 0.8% tropicamide with 0.5% phenylephrine was used to achieve cycloplegia and paralysis of accommodation. 599 newborn babies participated in the study. Data pertaining to the right eye is utilized for all the analyses except that for anisometropia where the two eyes were compared. Growth parameters were measured soon after birth. Simple linear regression analysis was performed to see the association of refractive status, (mean spherical equivalent (MSE), astigmatism and anisometropia) with each of the study variables, namely gestation, length, weight and head circumference. Subsequently, multiple linear regression was carried out to identify the independent predictors for each of the outcome parameters. Results Simple linear regression showed a significant relation between all 4 study variables and refractive error but in multiple regression only gestational age and weight were related to refractive error. The partial correlation of weight with MSE adjusted for gestation was 0.28 and that of gestation with MSE adjusted for weight was 0.10. Birth weight had a higher correlation to MSE than gestational age. Conclusion This is the first study to look at refractive error against all these growth parameters, in preterm and term babies at birth. It would appear from this study that birth weight rather than gestation should be used as criteria for screening for refractive error, especially in developing
Raji Mathew Varghese
Full Text Available Refractive status at birth is related to gestational age. Preterm babies have myopia which decreases as gestational age increases and term babies are known to be hypermetropic. This study looked at the correlation of refractive status with birth weight in term and preterm babies, and with physical indicators of intra-uterine growth such as the head circumference and length of the baby at birth.All babies delivered at St. Stephens Hospital and admitted in the nursery were eligible for the study. Refraction was performed within the first week of life. 0.8% tropicamide with 0.5% phenylephrine was used to achieve cycloplegia and paralysis of accommodation. 599 newborn babies participated in the study. Data pertaining to the right eye is utilized for all the analyses except that for anisometropia where the two eyes were compared. Growth parameters were measured soon after birth. Simple linear regression analysis was performed to see the association of refractive status, (mean spherical equivalent (MSE, astigmatism and anisometropia with each of the study variables, namely gestation, length, weight and head circumference. Subsequently, multiple linear regression was carried out to identify the independent predictors for each of the outcome parameters.Simple linear regression showed a significant relation between all 4 study variables and refractive error but in multiple regression only gestational age and weight were related to refractive error. The partial correlation of weight with MSE adjusted for gestation was 0.28 and that of gestation with MSE adjusted for weight was 0.10. Birth weight had a higher correlation to MSE than gestational age.This is the first study to look at refractive error against all these growth parameters, in preterm and term babies at birth. It would appear from this study that birth weight rather than gestation should be used as criteria for screening for refractive error, especially in developing countries where the
How to classify plantar plate injuries: parameters from history and physical examination.
Nery, Caio; Coughlin, Michael; Baumfeld, Daniel; Raduan, Fernando; Mann, Tania Szejnfeld; Catena, Fernanda
2015-01-01
To find the best clinical parameters for defining and classifying the degree of plantar plate injuries. Sixty-eight patients (100 metatarsophalangeal joints) were classified in accordance with the Arthroscopic Anatomical Classification for plantar plate injuries and were divided into five groups (0 to IV). Their medical files were reviewed and the incidence of each parameter for the respective group was correlated. These parameters were: use of high heels, sports, acute pain, local edema, Mulder's sign, widening of the interdigital space, pain in the head of the corresponding metatarsal, touching the ground, "drawer test", toe grip and toe deformities (in the sagittal, coronal and transversal planes). There were no statistically significant associations between the degree of injury and use of high-heel shoes, sports trauma, pain at the head of the metatarsal, Mulder's sign, deformity in pronation or displacement in the transversal and sagittal planes (although their combination, i.e. "cross toe", showed a statistically significant correlation). Positive correlations with the severity of the injuries were found in relation to initial acute pain, progressive widening of the interdigital space, loss of "touching the ground", positive results from the "drawer test" on the metatarsophalangeal joint, diminished grip strength and toe deformity in supination. The "drawer test" was seen to be the more reliable and precise tool for classifying the degree of plantar plate injury, followed by "touching the ground" and rotational deformities. It is possible to improve the precision of the diagnosis and the predictions of the anatomical classification for plantar plate injuries through combining the clinical history and data from the physical examination.
Physics of societal issues calculations on national security, environment, and energy
Hafemeister, David
2007-01-01
Why this book on the Physics of Societal Issues? The subdivisions of physics - nuclear physics, particle physics, condensed-matter physics, biophysics - have their textbooks, while the subdivision of physics and society lacks an equation-oriented text on the physics of arms, energy and the environment. Physics of Societal Issues is intended for undergraduate and doctoral students who may work on applied topics, or who simply want to know why things are the way they are. Decisions guiding policies on nuclear arms, energy and the environment often seem mysterious and contradictory. What is the science behind the deployment of MIRVed ICBMs, the quest for space-based beam weapons, the fear of powerline EM fields, the wholesale acceptance of SUVs, the issues of climactic change, and the failure of the pre-embargo market to produce buildings and appliances that now save over 50 power plants? Physics of Societal Issues is three "mini-texts" in one: National Security (5 chapters): Weapons, offense, defense, verificat...
Chowdhury, Md Albarune; de Neergaard, Andreas; Jensen, Lars Stoumann
2014-01-01
Solid-liquid separation of animal slurry, with solid fractions used for composting, has gained interest recently. However, efficient composting of separated animal slurry solid fractions (SSFs) requires a better understanding of the process dynamics in terms of important physical parameters and their interacting physical relationships in the composting matrix. Here we monitored moisture content, bulk density, particle density and air-filled porosity (AFP) during composting of SSF collected from four commercially available solid-liquid separators. Composting was performed in laboratory-scale reactors for 30 days (d) under forced aeration and measurements were conducted on the solid samples at the beginning of composting and at 10-d intervals during composting. The results suggest that differences in initial physical properties of SSF influence the development of compost maximum temperatures (40-70 degreeC). Depending on SSF, total wet mass and volume losses (expressed as % of initial value) were up to 37% and 34%, respectively. After 30 d of composting, relative losses of total solids varied from 17.9% to 21.7% and of volatile solids (VS) from 21.3% to 27.5%, depending on SSF. VS losses in all composts showed different dynamics as described by the first-order kinetic equation. The estimated component particle density of 1441 kg m-3 for VS and 2625 kg m-3 for fixed solids can be used to improve estimates of AFP for SSF within the range tested. The linear relationship between wet bulk density and AFP reported by previous researchers held true for SSF.
Tariq, Sundus; Lone, Khalid Parvez; Tariq, Saba
2016-01-01
Background and objectives: Optimal physical activity is important in attaining a peak bone mass. Physically active women have better bone mineral density and reduce fracture risk as compared to females living a sedentary life. The objective of this study was to compare parameters of bone profile and serum homocysteine levels in physically active and non-active postmenopausal females. Methods: In this cross sectional study postmenopausal females between 50-70 years of age were recruited and di...
Program MCU for Monte-Carlo calculations of neutron-physical characteristics of nuclear reactors
Abagyan, L.P.; Alekseev, N.I.; Bryzgalov, V.I.; Glushkov, A.E.; Gomin, E.A.; Gurevich, M.I.; Kalugin, M.A.; Majorov, L.V.; Marin, S.V.; Yhdkevich, M.S.
1994-01-01
A description of the MCU data modification is presented. The calculation results by the MCU-2 and MCU-3 codes are compared for the critical assemblies of a different reactor types. The full list of the critical assemblies calculation results obtained by all MCU code versions is given. 32 refs.; 32 tabs
Rosing, L. M.
1976-01-01
Physical, chemical and biological water quality data from five sites in the Tennessee River, two in Guntersville Reservoir and three in Wheeler Reservoir were correlated with climatological data for three annual cycles. Two of the annual cycles are for the years prior to the Browns Ferry Nuclear Power Plant operations and one is for the first 14 months of Plant operations. A comparison of the results of the annual cycles indicates that two distinct physical conditions in the reservoirs occur, one during the warm months when the reservoirs are at capacity and one during the colder winter months when the reservoirs have been drawn-down for water storage during the rainy months and for weed control. The wide variations of physical and chemical parameters to which the biological organisms are subjected on an annual basis control the biological organisms and their population levels. A comparison of the parameters of the site below the Power plant indicates that the heated effluent from the plant operating with two of the three reactors has not had any effect on the organisms at this site. Recommendations given include the development of prediction mathematical models (statistical analysis) for the physical and chemical parameters under specific climatological conditions which affect biological organisms. Tabulated data of chemical analysis of water and organism populations studied is given.
Vehauc, A [Institute of Nuclear Sciences VINCA, Belgrade (Yugoslavia)
1992-07-01
Physical parameters of the effluent dispersed from the wet cooling towers, i.e. mixture of the warm moist air with the entrained droplets are analysed. Understanding of the effluent physical parameters at the exit of cooling tower is important for prediction of the effluent dispersion in the environment. Mass and droplet diameter distributors of the drifted cooling water are measured in situ and also, drift eliminators are characterised experimentally. A new numerical method for heat and mass transfer evaluation in the cooling tower packing (fill) was developed, that leads to more accurate prediction for outlet air parameters in relation of plant power rate, cooling tower characteristics and atmospheric conditions. (author)
Tariq, Sundus; Lone, Khalid Parvez; Tariq, Saba
2016-01-01
Optimal physical activity is important in attaining a peak bone mass. Physically active women have better bone mineral density and reduce fracture risk as compared to females living a sedentary life. The objective of this study was to compare parameters of bone profile and serum homocysteine levels in physically active and non-active postmenopausal females. In this cross sectional study postmenopausal females between 50-70 years of age were recruited and divided into two groups: Physically inactive (n=133) performing light physical activity and Physically active (n=34) performing moderate physical activity. Physical activity (in metabolic equivalents), bone mineral density and serum homocysteine levels were assessed. Spearman's rho correlation was applied to observe correlations. Two independent sample t test and Mann Whitney U test were applied to compare groups. P-value ≤ 0.05 was taken statistically significant. Parameters of bone profile were significantly higher and serum homocysteine levels were significantly lower in postmenopausal females performing moderate physical activity as compared to females performing light physical activity. Homocysteine was not significantly related to T-score and Z-score in both groups. Improving physical activity could be beneficial for improving the quality of bone, decreasing fracture risk and decreasing serum homocysteine levels.
Yang, Mei; Wen-Chen, Zheng; Hong-Gang, Liu
2013-01-01
The spin-Hamiltonian parameters (g factors g i and hyperfine structure constants A i , were i=x, y and z) for Mo 5+ ion occupying the Ti(1) site with approximately rhombic symmetry in KTiOPO 4 crystal are calculated from the high-order perturbation formulas based on the two-mechanism model. In the model, not only the contribution due to the conventional crystal-field (CF) mechanism, but also those due to the charge-transfer (CT) mechanism are included. The six calculated spin-Hamiltonian parameters with four adjustable parameters are in reasonable agreement with the experimental values. The calculations show that for more accurate calculations of spin-Hamiltonian parameters of the high valence d n ions (e.g., Mo 5+ considered here) in crystals, the contribution from CT mechanism, which is ignored in the conventional crystal field theory, should be taken into account. The reasonable crystal field energy levels of Mo 5+ in KTiOPO 4 are also predicted from calculations
Biyajima, M.; Shirane, K.; Terazawa, O.
1987-01-01
We calculate cross sections for production of the standard Higgs boson in e + e - collisions and compare our results with those of several authors. It is found that there are appreciable differences among them which can be attributed to the coupling constants used, α(0) ( = (1/137) and G/sub F/. We also observe that cross sections depend on the magnitudes of the total width of the Z particle. The use of a reasonable set of parameters in calculations is emphasized