Energy Technology Data Exchange (ETDEWEB)
Dickerson, M.H.
1980-08-01
ARAC was on-line calculating hourly concentration values during the TMI-2 venting of /sup 85/Kr gas from June 28 to July 11, 1980. During this time hourly isopleths of normalized instantaneous concentration were calculated and transmitted to EPA in Middletown, PA. These isopleths were used to help locate the EPA and Penn State mobile air samplers and they were used for comparison to the EPA fixed 24 hr sampler measurements and the DOE helicopter measurements. This report summarizes preliminary comparisons for the EPA fixed samplers and the DOE helicopters.
DEFF Research Database (Denmark)
Cai, Xiao-Xiao; Llamas-Jansa, Isabel; Mullet, Steven
2013-01-01
to reactor modelling. Before version 9.5, Geant4 HP thermal scattering model (i.e. the S(α; β) model ) supports only three bounded isotopes, namely, H in water and polyethylene, and C in graphite. Newly supported materials include D in heavy water, O and Be in beryllium oxide, H and Zr in zirconium hydride......, U and O in uranium dioxide, Al metal, Be metal, and Fe metal. The native HP cross section library G4NDL does not include data for elements with atomic number larger than 92. Therefore, transuranic elements, which have impacts for a realistic reactor, can not be simulated by the combination of the HP...
Hubbard, W B
2016-01-01
In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen-helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses, and a hydrogen-helium-rich envelope with...
Hubbard, W. B.; Militzer, B.
2016-03-01
In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen-helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen-helium-rich envelope with approximately three times solar metallicity.
Energy Technology Data Exchange (ETDEWEB)
Hubbard, W. B. [Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Militzer, B. [Department of Earth and Planetary Science, Department of Astronomy, University of California, Berkeley, CA 94720 (United States)
2016-03-20
In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen–helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen–helium-rich envelope with approximately three times solar metallicity.
Preliminary reference Earth model
Dziewonski, Adam M.; Anderson, Don L.
1981-06-01
A large data set consisting of about 1000 normal mode periods, 500 summary travel time observations, 100 normal mode Q values, mass and moment of inertia have been inverted to obtain the radial distribution of elastic properties, Q values and density in the Earth's interior. The data set was supplemented with a special study of 12 years of ISC phase data which yielded an additional 1.75 × 10 6 travel time observations for P and S waves. In order to obtain satisfactory agreement with the entire data set we were required to take into account anelastic dispersion. The introduction of transverse isotropy into the outer 220 km of the mantle was required in order to satisfy the shorter period fundamental toroidal and spheroidal modes. This anisotropy also improved the fit of the larger data set. The horizontal and vertical velocities in the upper mantle differ by 2-4%, both for P and S waves. The mantle below 220 km is not required to be anisotropic. Mantle Rayleigh waves are surprisingly sensitive to compressional velocity in the upper mantle. High S n velocities, low P n velocities and a pronounced low-velocity zone are features of most global inversion models that are suppressed when anisotropy is allowed for in the inversion. The Preliminary Reference Earth Model, PREM, and auxiliary tables showing fits to the data are presented.
Energy Technology Data Exchange (ETDEWEB)
Manning, Karessa L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dolislager, Fredrick G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bellamy, Michael B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2016-11-01
The Preliminary Remediation Goal (PRG) and Dose Compliance Concentration (DCC) calculators are screening level tools that set forth Environmental Protection Agency's (EPA) recommended approaches, based upon currently available information with respect to risk assessment, for response actions at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites, commonly known as Superfund. The screening levels derived by the PRG and DCC calculators are used to identify isotopes contributing the highest risk and dose as well as establish preliminary remediation goals. Each calculator has a residential gardening scenario and subsistence farmer exposure scenarios that require modeling of the transfer of contaminants from soil and water into various types of biota (crops and animal products). New publications of human intake rates of biota; farm animal intakes of water, soil, and fodder; and soil to plant interactions require updates be implemented into the PRG and DCC exposure scenarios. Recent improvements have been made in the biota modeling for these calculators, including newly derived biota intake rates, more comprehensive soil mass loading factors (MLFs), and more comprehensive soil to tissue transfer factors (TFs) for animals and soil to plant transfer factors (BV's). New biota have been added in both the produce and animal products categories that greatly improve the accuracy and utility of the PRG and DCC calculators and encompass greater geographic diversity on a national and international scale.
Preliminary Calculation on a Spent Fuel Pool Accident using GOTHIC
Energy Technology Data Exchange (ETDEWEB)
Park, Jaehwan; Choi, Yu Jung; Hong, Tae Hyub; Kim, Hyeong-Taek [KHNP-CRI, Daejeon (Korea, Republic of)
2015-10-15
The probability of an accident happening at the spent fuel pool was believed to be quite low until the 2011 Fukushima accident occurred. Notably, large amount of spent fuel are normally stored in the spent fuel pool for a long time compared to the amount of fuel in the reactor core and the total heat released from the spent fuel is high enough to boil the water of the spent fuel pool when the cooling system does not operate. In addition, the enrichment and the burnup of the fuel have both increased in the past decade and heat generation from the spent fuel thereby has also increased. The failure of the cooling system at the spent fuel pool (hereafter, a loss-of-cooling accident) is one of the principal hypothetical causes of an accident that could occur at the spent fuel pool. In this paper, the preliminary calculation of a loss-of-cooling accident was performed. In this paper, the preliminary calculation of a loss-of cooling accident was performed with GOTHIC. The calculation results show boiling away of water in the spent fuel pool due to the loss-of-cooling accident and similar thermal performance of the spent fuel pool with previous research results.
Preliminary ECLSS waste water model
Carter, Donald L.; Holder, Donald W., Jr.; Alexander, Kevin; Shaw, R. G.; Hayase, John K.
1991-01-01
A preliminary waste water model for input to the Space Station Freedom (SSF) Environmental Control and Life Support System (ECLSS) Water Processor (WP) has been generated for design purposes. Data have been compiled from various ECLSS tests and flight sample analyses. A discussion of the characterization of the waste streams comprising the model is presented, along with a discussion of the waste water model and the rationale for the inclusion of contaminants in their respective concentrations. The major objective is to establish a methodology for the development of a waste water model and to present the current state of that model.
Preliminary ECLSS waste water model
Carter, Donald L.; Holder, Donald W., Jr.; Alexander, Kevin; Shaw, R. G.; Hayase, John K.
1991-01-01
A preliminary waste water model for input to the Space Station Freedom (SSF) Environmental Control and Life Support System (ECLSS) Water Processor (WP) has been generated for design purposes. Data have been compiled from various ECLSS tests and flight sample analyses. A discussion of the characterization of the waste streams comprising the model is presented, along with a discussion of the waste water model and the rationale for the inclusion of contaminants in their respective concentrations. The major objective is to establish a methodology for the development of a waste water model and to present the current state of that model.
Preliminary skyshine calculations for the Poloidal Diverter Tokamak Experiment
Nigg, D. W.; Wheeler, F. J.
1981-01-01
A calculational model is presented to estimate the radiation dose, due to the skyshine effect, in the control room and at the site boundary of the Poloidal Diverter Experiment (PDX) facility at Princeton University which requires substantial radiation shielding. The required composition and thickness of a water-filled roof shield that would reduce this effect to an acceptable level is computed, using an efficient one-dimensional model with an Sn calculation in slab geometry. The actual neutron skyshine dose is computed using a Monte Carlo model with the neutron source at the roof surface obtained from the slab Sn calculation, and the capture gamma dose is computed using a simple point-kernel single-scatter method. It is maintained that the slab model provides the exact probability of leakage out the top surface of the roof and that it is nearly as accurate as and much less costly than multi-dimensional techniques.
The 239 Pu(n,2n)238Pu cross section: preliminary calculations
Energy Technology Data Exchange (ETDEWEB)
Chen, H; Reffo, G; Ross, M A; White, R M
1999-03-12
The primary motivation for the present work is to provide theoretical values for the ratio of the partial ^{239}Pu(n,2nx{gamma})^{238}Pu to total ^{239} Pu(n,2n)^{238}Pu cross section for several discrete gamma transitions. Results and conclusions of preliminary calculations from threshold to 20 MeV are presented. Calculations are based on theoretical models with parameters obtained from the literature or from our ad hoc systematics. Optical model cross sections and transmission coefficients were determined using the coupled-channels method. The calculations included a preequilibrium component followed by multiple particle and gamma-ray emissions. Fission competition was included at all stages of de-excitation. Suggestions for further verifications and possible improvements are provided.
Red Giant Oscillations: Stellar Models and Mode Frequency Calculations
DEFF Research Database (Denmark)
Jendreieck, A.; Weiss, A.; Aguirre, Victor Silva
2012-01-01
We present preliminary results on modelling KIC 7693833, the so far most metal-poor red-giant star observed by {\\it Kepler}. From time series spanning several months, global oscillation parameters and individual frequencies were obtained and compared to theoretical calculations. Evolution models ......_\\odot$ in radius and of about 2.5 Gyr in age....
Parallel processing of atmospheric chemistry calculations: Preliminary considerations
Energy Technology Data Exchange (ETDEWEB)
Elliott, S.; Jones, P.
1995-01-01
Global climate calculations are already saturating the class modern vector supercomputers with only a few central processing units. Increased resolution and inclusion of routines to deal with biogeochemical portions of the terrestrial climate system will soon demand massively parallel approaches. The atmospheric photochemistry ensemble is intimately linked to climate through the trace greenhouse gases ozone and methane and modules for representing it are being attached to global three dimensional transport and GCM frameworks. Atmospheric kinetics involve dozens of highly interactive tracers and so will accentuate the need for parallel processing of earth system simulations. In the present text we lay some of the groundwork for addition of atmospheric kinetics packages to GCM and global scale atmospheric models on multiply parallel computers. The discussion is tailored for consumption by the photochemical modelling community. After a review of numerical atmospheric chemistry methods, we examine how kinetics can be implemented on a parallel computer. We concentrate especially on data layout and flexibility and how these can be implemented in various programming models. We conclude that chemistry can be implemented rather easily within existing frameworks of several parallel atmospheric models. However, memory limitations may preclude high resolution studies of global chemistry.
Comparison of Calculation Models for Bucket Foundation in Sand
DEFF Research Database (Denmark)
Vaitkunaite, Evelina; Molina, Salvador Devant; Ibsen, Lars Bo
The possibility of fast and rather precise preliminary offshore foundation design is desirable. The ultimate limit state of bucket foundation is investigated using three different geotechnical calculation tools: [Ibsen 2001] an analytical method, LimitState:GEO and Plaxis 3D. The study has focused...... on resultant bearing capacity of variously embedded foundation in sand. The 2D models, [Ibsen 2001] and LimitState:GEO can be used for the preliminary design because they are fast and result in a rather similar bearing capacity calculation compared with the finite element models of Plaxis 3D. The 2D models...... and their results are compared to the finite element model in Plaxis 3D in this article....
Modeling the complete Otto cycle: Preliminary version. [computer programming
Zeleznik, F. J.; Mcbride, B. J.
1977-01-01
A description is given of the equations and the computer program being developed to model the complete Otto cycle. The program incorporates such important features as: (1) heat transfer, (2) finite combustion rates, (3) complete chemical kinetics in the burned gas, (4) exhaust gas recirculation, and (5) manifold vacuum or supercharging. Changes in thermodynamic, kinetic and transport data as well as model parameters can be made without reprogramming. Preliminary calculations indicate that: (1) chemistry and heat transfer significantly affect composition and performance, (2) there seems to be a strong interaction among model parameters, and (3) a number of cycles must be calculated in order to obtain steady-state conditions.
MR imaging of prostate. Preliminary experience with calculated imaging in 28 cases
Energy Technology Data Exchange (ETDEWEB)
Gevenois, P.A.; Van Regemorter, G.; Ghysels, M.; Delepaut, A.; Van Gansbeke, D.; Struyven, J.
1988-04-01
The majority of studies with MR imaging in prostate disease are based on a semiology obtained using images weighted in T1 and T2. A study was carried out to evaluate effects of images calculated in T1 and T2 obtained at 0.5T. This preliminary study concerns 28 prostate examinations with spin-echo acquisition and inversion-recuperation parameters, and provided images calculated in T1, weighted and calculated in T2. Images allowed detection and characterization of prostate lesions. However, although calculated images accentuate discrimination of the method, the weighted images conserve their place because of their improved spatial resolution.
Verification of EPA's " Preliminary remediation goals for radionuclides" (PRG) electronic calculator
Energy Technology Data Exchange (ETDEWEB)
Stagich, B. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2017-03-29
The U.S. Environmental Protection Agency (EPA) requested an external, independent verification study of their “Preliminary Remediation Goals for Radionuclides” (PRG) electronic calculator. The calculator provides information on establishing PRGs for radionuclides at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites with radioactive contamination (Verification Study Charge, Background). These risk-based PRGs set concentration limits using carcinogenic toxicity values under specific exposure conditions (PRG User’s Guide, Section 1). The purpose of this verification study is to ascertain that the computer codes has no inherit numerical problems with obtaining solutions as well as to ensure that the equations are programmed correctly.
Preliminary Model of Porphyry Copper Deposits
Berger, Byron R.; Ayuso, Robert A.; Wynn, Jeffrey C.; Seal, Robert R., II
2008-01-01
The U.S. Geological Survey (USGS) Mineral Resources Program develops mineral-deposit models for application in USGS mineral-resource assessments and other mineral resource-related activities within the USGS as well as for nongovernmental applications. Periodic updates of models are published in order to incorporate new concepts and findings on the occurrence, nature, and origin of specific mineral deposit types. This update is a preliminary model of porphyry copper deposits that begins an update process of porphyry copper models published in USGS Bulletin 1693 in 1986. This update includes a greater variety of deposit attributes than were included in the 1986 model as well as more information about each attribute. It also includes an expanded discussion of geophysical and remote sensing attributes and tools useful in resource evaluations, a summary of current theoretical concepts of porphyry copper deposit genesis, and a summary of the environmental attributes of unmined and mined deposits.
[Tuscan Chronic Care Model: a preliminary analysis].
Barbato, Angelo; Meggiolaro, Angela; Rossi, Luigi; Fioravanti, C; Palermita, F; La Torre, Giuseppe
2015-01-01
the aim of this study is to present a preliminary analysis of efficacy and effectiveness of a model of chronically ill care (Chronic Care Model, CCM). the analysis took into account 106 territorial modules, 1016 General Practitioners and 1,228,595 patients. The diagnostic and therapeutic pathways activated (PDTA), involved four chronic conditions, selected according to the prevalence and incidence, in Tuscany Region: Diabetes Mellitus (DM), Heart Failure (SC), Chronic Obstructive Pulmonary Disease (COPD) and stroke. Six epidemiological indicators of process and output were selected, in order to measure the model of care performed, before and after its application: adherence to specific follow-up for each pathology (use of clinical and laboratory indicators), annual average of expenditure per/capita/euro for diagnostic tests, in laboratory and instrumental, average expenditure per/capita/year for specialist visits; hospitalization rate for diseases related to the main pathology, hospitalization rate for long-term complications and rate of access to the emergency department (ED). Data were collected through the database; the differences before and after the intervention and between exposed and unexposed, were analyzed by method "Before-After (Controlled and Uncontrolled) Studies". The impact of the intervention was calculated as DD (difference of the differences). DM management showed an increased adhesion to follow-up (DD: +8.1%), and the use of laboratory diagnostics (DD: +4,9 €/year/pc), less hospitalization for long-term complications and for endocrine related diseases (DD respectively: 5.8/1000 and DD: +1.2/1000), finally a smaller increase of access to PS (DD: -1.6/1000), despite a slight increase of specialistic visits (DD: +0,38 €/year/pc). The management of SC initially showed a rising adherence to follow-up (DD: +2.3%), a decrease of specialist visits (DD:E 1.03 €/year/pc), hospitalization and access to PS for exacerbations (DD: -4.4/1000 and DD: -6
A Preliminary Calculation of 235U (n,2n) 234U Cross Sections
Energy Technology Data Exchange (ETDEWEB)
Chen, H.; Ross, M.A.; Reffo, G.; White, R.M.; Younes, W.
1999-11-23
Preliminary calculations of the total two-neutron emission cross section, {sup 235}U(n,2n) {sup 234}U and the partial two-neutron emission cross sections, {sup 235}U(n, 2n{gamma}) {sup 234}U, are presented. The {sup 235}U(n, 2n{gamma}) {sup 234}U cross sections describe the process of {gamma}-decays in the residual nucleus following the two-neutron emission and were calculated for several {gamma}-transitions between states of the ground-state band of the {sup 234}U nucleus. All three reaction mechanisms, namely, direct, pre-equilibrium and compound, were included. In addition, fission competition as well as {gamma}-cascade were considered in the compound component of the cross section calculations. A comparison with the relevant experimental data obtained from the GEANIE detector at the LANSCE/WNR facility in Los Alamos was also carried out.
A revised calculational model for fission
Energy Technology Data Exchange (ETDEWEB)
Atchison, F.
1998-09-01
A semi-empirical parametrization has been developed to calculate the fission contribution to evaporative de-excitation of nuclei with a very wide range of charge, mass and excitation-energy and also the nuclear states of the scission products. The calculational model reproduces measured values (cross-sections, mass distributions, etc.) for a wide range of fissioning systems: Nuclei from Ta to Cf, interactions involving nucleons up to medium energy and light ions. (author)
Directory of Open Access Journals (Sweden)
István Bors
2015-09-01
Full Text Available Maize (Zea mays L. is often contaminated with Fusarium verticillioides. This harmful fungus produces fumonisins as secondary metabolites. These fumonisins can appear both free and hidden form in planta. The hidden form is usually bound covalently to cereal starch. From the hidden fumonisins, during enzymatic degradation, glycosides are formed, and the fumonisin is further decomposed during a de-esterification step. In this short communication some preliminary DFT calculated structural results which could be useful in the future to help to understand the van der Waals force controlled molecular interactions between these kinds of mycotoxin molecules and enzymes are demonstrated.
Precipitates/Salts Model Sensitivity Calculation
Energy Technology Data Exchange (ETDEWEB)
P. Mariner
2001-12-20
The objective and scope of this calculation is to assist Performance Assessment Operations and the Engineered Barrier System (EBS) Department in modeling the geochemical effects of evaporation on potential seepage waters within a potential repository drift. This work is developed and documented using procedure AP-3.12Q, ''Calculations'', in support of ''Technical Work Plan For Engineered Barrier System Department Modeling and Testing FY 02 Work Activities'' (BSC 2001a). The specific objective of this calculation is to examine the sensitivity and uncertainties of the Precipitates/Salts model. The Precipitates/Salts model is documented in an Analysis/Model Report (AMR), ''In-Drift Precipitates/Salts Analysis'' (BSC 2001b). The calculation in the current document examines the effects of starting water composition, mineral suppressions, and the fugacity of carbon dioxide (CO{sub 2}) on the chemical evolution of water in the drift.
Modeling Malaysia's Energy System: Some Preliminary Results
Directory of Open Access Journals (Sweden)
Ahmad M. Yusof
2011-01-01
Full Text Available Problem statement: The current dynamic and fragile world energy environment necessitates the development of new energy model that solely caters to analyze Malaysias energy scenarios. Approach: The model is a network flow model that traces the flow of energy carriers from its sources (import and mining through some conversion and transformation processes for the production of energy products to final destinations (energy demand sectors. The integration to the economic sectors is done exogeneously by specifying the annual sectoral energy demand levels. The model in turn optimizes the energy variables for a specified objective function to meet those demands. Results: By minimizing the inter temporal petroleum product imports for the crude oil system the annual extraction level of Tapis blend is projected at 579600 barrels per day. The aggregate demand for petroleum products is projected to grow at 2.1% year-1 while motor gasoline and diesel constitute 42 and 38% of the petroleum products demands mix respectively over the 5 year planning period. Petroleum products import is expected to grow at 6.0% year-1. Conclusion: The preliminary results indicate that the model performs as expected. Thus other types of energy carriers such as natural gas, coal and biomass will be added to the energy system for the overall development of Malaysia energy model.
Directory of Open Access Journals (Sweden)
Żelazny Katarzyna
2015-01-01
Full Text Available During ship design, its service speed is one of the crucial parameters which decide on future economic effects. As sufficiently exact calculation methods applicable to preliminary design stage are lacking the so called contract speed which a ship reaches in calm water is usually applied. In the paper [11] a parametric method for calculation of total ship resistance in actual weather conditions (wind, waves, sea current, was presented. This paper presents a parametric model of ship propulsion system (screw propeller - propulsion engine as well as a calculation method, based on both models, of mean statistical value of ship service speed in seasonal weather conditions occurring on shipping lines. The method makes use of only basic design parameters and may be applied in preliminary design stage.
Configuration mixing calculations in soluble models
Cambiaggio, M. C.; Plastino, A.; Szybisz, L.; Miller, H. G.
1983-07-01
Configuration mixing calculations have been performed in two quasi-spin models using basis states which are solutions of a particular set of Hartree-Fock equations. Each of these solutions, even those which do not correspond to the global minimum, is found to contain interesting physical information. Relatively good agreement with the exact lowest-lying states has been obtained. In particular, one obtains a better approximation to the ground state than that provided by Hartree-Fock.
Tidal Response of Preliminary Jupiter Model
Wahl, Sean M; Hubbard, Willam B.; Militzer, Burkhard
2016-01-01
In anticipation of improved observational data for Jupiter's gravitational field from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms using the non-perturbative concentric Maclaurin Spheroid (CMS) method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal...
Preliminary Phase Field Computational Model Development
Energy Technology Data Exchange (ETDEWEB)
Li, Yulan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hu, Shenyang Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Xu, Ke [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Suter, Jonathan D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McCloy, John S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Bradley R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ramuhalli, Pradeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2014-12-15
experiments, special experimental methods were devised to create similar boundary conditions in the iron films. Preliminary MFM studies conducted on single and polycrystalline iron films with small sub-areas created with focused ion beam have correlated quite well qualitatively with phase-field simulations. However, phase-field model dimensions are still small relative to experiments thus far. We are in the process of increasing the size of the models and decreasing specimen size so both have identical dimensions. Ongoing research is focused on validation of the phase-field model. Validation is being accomplished through comparison with experimentally obtained MFM images (in progress), and planned measurements of major hysteresis loops and first order reversal curves. Extrapolation of simulation sizes to represent a more stochastic bulk-like system will require sampling of various simulations (i.e., with single non-magnetic defect, single magnetic defect, single grain boundary, single dislocation, etc.) with distributions of input parameters. These outputs can then be compared to laboratory magnetic measurements and ultimately to simulate magnetic Barkhausen noise signals.
Matrix model calculations beyond the spherical limit
Energy Technology Data Exchange (ETDEWEB)
Ambjoern, J. (Niels Bohr Institute, Copenhagen (Denmark)); Chekhov, L. (L.P.T.H.E., Universite Pierre et Marie Curie, 75 - Paris (France)); Kristjansen, C.F. (Niels Bohr Institute, Copenhagen (Denmark)); Makeenko, Yu. (Institute of Theoretical and Experimental Physics, Moscow (Russian Federation))
1993-08-30
We propose an improved iterative scheme for calculating higher genus contributions to the multi-loop (or multi-point) correlators and the partition function of the hermitian one matrix model. We present explicit results up to genus two. We develop a version which gives directly the result in the double scaling limit and present explicit results up to genus four. Using the latter version we prove that the hermitian and the complex matrix model are equivalent in the double scaling limit and that in this limit they are both equivalent to the Kontsevich model. We discuss how our results away from the double scaling limit are related to the structure of moduli space. (orig.)
Cost Calculation Model for Logistics Service Providers
Directory of Open Access Journals (Sweden)
Zoltán Bokor
2012-11-01
Full Text Available The exact calculation of logistics costs has become a real challenge in logistics and supply chain management. It is essential to gain reliable and accurate costing information to attain efficient resource allocation within the logistics service provider companies. Traditional costing approaches, however, may not be sufficient to reach this aim in case of complex and heterogeneous logistics service structures. So this paper intends to explore the ways of improving the cost calculation regimes of logistics service providers and show how to adopt the multi-level full cost allocation technique in logistics practice. After determining the methodological framework, a sample cost calculation scheme is developed and tested by using estimated input data. Based on the theoretical findings and the experiences of the pilot project it can be concluded that the improved costing model contributes to making logistics costing more accurate and transparent. Moreover, the relations between costs and performances also become more visible, which enhances the effectiveness of logistics planning and controlling significantly
Preliminary deformation model for National Seismic Hazard map of Indonesia
Energy Technology Data Exchange (ETDEWEB)
Meilano, Irwan; Gunawan, Endra; Sarsito, Dina; Prijatna, Kosasih; Abidin, Hasanuddin Z. [Geodesy Research Division, Faculty of Earth Science and Technology, Institute of Technology Bandung (Indonesia); Susilo,; Efendi, Joni [Agency for Geospatial Information (BIG) (Indonesia)
2015-04-24
Preliminary deformation model for the Indonesia’s National Seismic Hazard (NSH) map is constructed as the block rotation and strain accumulation function at the elastic half-space. Deformation due to rigid body motion is estimated by rotating six tectonic blocks in Indonesia. The interseismic deformation due to subduction is estimated by assuming coupling on subduction interface while deformation at active fault is calculated by assuming each of the fault‘s segment slips beneath a locking depth or in combination with creeping in a shallower part. This research shows that rigid body motion dominates the deformation pattern with magnitude more than 15 mm/year, except in the narrow area near subduction zones and active faults where significant deformation reach to 25 mm/year.
Energy Technology Data Exchange (ETDEWEB)
Davidson, S; Followill, D; Ibbott, G [University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Cui, J; Deasy, J [Washington University, St. Louis, MO (United States)], E-mail: sedavids@mdanderson.org
2008-02-01
The Dose Planning Method (DPM) is one of several 'fast' Monte Carlo (MC) computer codes designed to produce an accurate dose calculation for advanced clinical applications. We have developed a flexible machine modeling process and validation tests for open-field and IMRT calculations. To complement the DPM code, a practical and versatile source model has been developed, whose parameters are derived from a standard set of planning system commissioning measurements. The primary photon spectrum and the spectrum resulting from the flattening filter are modeled by a Fatigue function, cut-off by a multiplying Fermi function, which effectively regularizes the difficult energy spectrum determination process. Commonly-used functions are applied to represent the off-axis softening, increasing primary fluence with increasing angle ('the horn effect'), and electron contamination. The patient dependent aspect of the MC dose calculation utilizes the multi-leaf collimator (MLC) leaf sequence file exported from the treatment planning system DICOM output, coupled with the source model, to derive the particle transport. This model has been commissioned for Varian 2100C 6 MV and 18 MV photon beams using percent depth dose, dose profiles, and output factors. A 3-D conformal plan and an IMRT plan delivered to an anthropomorphic thorax phantom were used to benchmark the model. The calculated results were compared to Pinnacle v7.6c results and measurements made using radiochromic film and thermoluminescent detectors (TLD)
Davidson, S.; Cui, J.; Followill, D.; Ibbott, G.; Deasy, J.
2008-02-01
The Dose Planning Method (DPM) is one of several 'fast' Monte Carlo (MC) computer codes designed to produce an accurate dose calculation for advanced clinical applications. We have developed a flexible machine modeling process and validation tests for open-field and IMRT calculations. To complement the DPM code, a practical and versatile source model has been developed, whose parameters are derived from a standard set of planning system commissioning measurements. The primary photon spectrum and the spectrum resulting from the flattening filter are modeled by a Fatigue function, cut-off by a multiplying Fermi function, which effectively regularizes the difficult energy spectrum determination process. Commonly-used functions are applied to represent the off-axis softening, increasing primary fluence with increasing angle ('the horn effect'), and electron contamination. The patient dependent aspect of the MC dose calculation utilizes the multi-leaf collimator (MLC) leaf sequence file exported from the treatment planning system DICOM output, coupled with the source model, to derive the particle transport. This model has been commissioned for Varian 2100C 6 MV and 18 MV photon beams using percent depth dose, dose profiles, and output factors. A 3-D conformal plan and an IMRT plan delivered to an anthropomorphic thorax phantom were used to benchmark the model. The calculated results were compared to Pinnacle v7.6c results and measurements made using radiochromic film and thermoluminescent detectors (TLD).
A preliminary model of wheelchair service delivery.
Eggers, Sara L; Myaskovsky, Larissa; Burkitt, Kelly H; Tolerico, Michelle; Switzer, Galen E; Fine, Michael J; Boninger, Michael L
2009-06-01
To integrate and expand on previously published models of wheelchair service delivery, and provide a preliminary framework for developing more comprehensive, descriptive models of wheelchair service delivery for adults with spinal cord injury within the U.S. health care system. Literature review and a qualitative analysis of in-depth interviews. Not applicable. Ten academic, clinical, regulatory, and industry experts (Department of Veterans Affairs [VA] and non-VA) in wheelchair service delivery. Not applicable. Interviewees were asked to discuss the full range of variables and stakeholders involved in wheelchair service delivery, and to limit their scope to the provision of primary subsequent or replacement chairs (not backup chairs) to adults within the United States. Most experts we interviewed stressed that clients who require a wheelchair play a central role in the wheelchair service delivery process. Providers (including clinicians, rehabilitation engineers, and rehabilitation counselors) are also critical stakeholders. More so than in other health care settings, suppliers play an integral role in the provision of wheelchairs to clients and may significantly influence the appropriateness of the wheelchair provided. Suppliers often have a direct role in wheelchair service delivery through their interactions with the clinician and/or client. This model also identified a number of system-level factors (including facility administration and standards, policies, and regulations) that influence wheelchair service delivery and ultimately the appropriateness of the wheelchair provided. We developed a detailed, descriptive model of wheelchair service delivery that integrates the delivery process and device outcomes, and includes the patient-level, provider-level, and system-level factors that may directly influence those processes and outcomes. We believe that this detailed model can help clinicians and researchers describe and consider the complexities of wheelchair
A Preliminary Model of Infrared Image Generation for Exhaust Plume
Directory of Open Access Journals (Sweden)
Fei Mei
2011-06-01
Full Text Available Based on the irradiance calculation of all pixels on the focal plane array, a preliminary infrared imaging prediction model of exhaust plume that have considered the geometrical and the thermal resolution of the camera was developed to understanding the infrared characteristics of exhaust plume. In order to compute the irradiance incident on each pixel, the gas radiation transfer path in the plume for the instantaneous field of view corresponds to the pixel was solved by the simultaneous equation of a enclosure cylinder which covers the exhaust plume and the line of sight. Radiance of the transfer path was calculated by radiation transfer equation for nonscattering gas. The radiative properties of combustion needed in the equation was provided by employing Malkmus model with EM2C narrow band database(25cm-1. The pressure, species concentration along the path was determination by CFD analysis. The relative irradiance intensity of each pixel was converted to color in the display according to gray map coding and hot map coding. Infrared image of the exhaust plumes from a subsonic axisymmetric nozzle with different relative position of camera and the plume was predicted with the model. By changing the parameters, such as FOV and space resolution, the image of different imaging system can be predicted.
A selection method for the calculation of preliminary risk-based remediation goals
Energy Technology Data Exchange (ETDEWEB)
Mahoney, L.A.; Batey, J.C.; Pintenich, J.L. [Eckenfelder Inc., Nashville, TN (United States)
1995-12-31
In the process of deriving acceptable concentrations of chemical constituents (or preliminary risk-based remediation goals, PRGs) for hazardous and other waste sites based on the site risk assessment results, it may be necessary or desirable to select a subset of constituents to focus the remainder of the site activities including the feasibility study and possibly, remedial design and verification sampling. Use of a focused set of action or clean-up goals offers the benefits of targeting those site areas where efforts should be concentrated, and reducing the cost and complexity of clean-up and verification sampling. Although the federal Superfund risk assessment guidance provides methods by which to calculate PRGs, no information is given on how to select which chemicals PRGs should be generated for. A method for this selection is presented which establishes: the media of interest; the populations for which PRGs should be generated; the relevant exposure route(s) for a given population to be used in calculating PRGs; and the individual constituents for which PRGs should be estimated. To illustrate this selection process, remedial investigation (RI) data and a baseline risk assessment for a hazardous waste site in Mississippi were used. The media of interest were identified as surface water and sediment from a creek that is adjacent to the site, on-site surface water, and groundwater from the uppermost aquifer. Of the 45 constituents detected in site-related waters, this selection process resulted in 16 for which PRGs were calculated, which served to focus the subsequent feasibility study efforts.
Energy Technology Data Exchange (ETDEWEB)
Jannik, Tim [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Stagich, Brooke [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2015-08-28
The U.S. Environmental Protection Agency (EPA) requested an external, independent verification study of their updated “Preliminary Remediation Goals for Radionuclides” (PRG) electronic calculator. The calculator provides PRGs for radionuclides that are used as a screening tool at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and Resource Conservation and Recovery Act (RCRA) sites. These risk-based PRGs establish concentration limits under specific exposure scenarios. The purpose of this verification study is to determine that the calculator has no inherit numerical problems with obtaining solutions as well as to ensure that the equations are programmed correctly. There are 167 equations used in the calculator. To verify the calculator, all equations for each of seven receptor types (resident, construction worker, outdoor and indoor worker, recreator, farmer, and composite worker) were hand calculated using the default parameters. The same four radionuclides (Am-241, Co-60, H-3, and Pu-238) were used for each calculation for consistency throughout.
Tidal Response of Preliminary Jupiter Model
Wahl, Sean M; Militzer, Burkhard
2016-01-01
In anticipation of improved observational data for Jupiter's gravitational field from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms using the non-perturbative concentric Maclaurin Spheroid (CMS) method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal and rotational perturbations, which we find to be important for a rapidly-rotating planet like Jupiter. Our predicted static tidal Love number $k_2 = 0.5900$ is $\\sim$10\\% larger than previous estimates. The value is, as expected, highly correlated with the zonal harmonic coefficient $J_2$, and is thus nearly constant when plausible changes are made to interior structure while holding $J_2$ fixed at the observed value. We note that the predicted static $k_2$ might change due to Jupiter's dynamical response to the Galilea...
Institute of Scientific and Technical Information of China (English)
唐斌; 康盛伟; 王先良; 黎杰; 王培
2016-01-01
Objective To investigate the feasibility of the virtual source model in Monte Carlo dose calculation for clinical radiotherapy.Methods The Monte Carlo simulation was used to obtain the phase space files which recorded the physical properties of the particles emitted by a medical linear accelerator, and the information on the type, energy spectrum, and distribution of particles were extracted from these files and analyzed to establish the semi-empirical model of virtual two-photon source.The GMC dose calculation engine was used to obtain the 3 cm×3 cm, 5 cm×5 cm, 10 cm×10 cm, 20 cm×20 cm, and 30 cm×30 cm fields of radiotherapy and the results of Monte Carlo simulation of dose distribution in three-dimensional water phantom in 2 intensity-modulated radiotherapy ( IMRT) plans.These results were compared with the results of water phantom measurement or the results of Elekta Monaco planning system to verify the accuracy of Monte Carlo dose calculation based on a virtual source.Results As for the percentage depth-dose distribution curves of the central axis of the water phantom and the off-axis dose curves at different depths in the five fields for radiotherapy, the difference between the results of Monte Carlo simulation and the results of measurement was within 1%.As for the two IMRT plans, the three-dimensional passing rates of Monaco calculation results and Monte Carlo simulation results were 98.9%and 99.4%, respectively, for 3%/3 mm, and 95.1%and 95.4%, respectively, for 2%/2 mm.Conclusions Monte Carlo simulation based on the virtual source model can obtain accurate results of radiotherapy dose calculation.%目的：研究临床放疗蒙特卡洛剂量计算方法中虚拟源模型的可行性。方法通过蒙特卡洛方法模拟得到记录医用直线加速器机头出射粒子物理特性的相空间文件，分析提取相空间文件中粒子的种类、能谱及位置分布，建立半经验虚拟双光子源抽样模型。结合并
Tidal Response of Preliminary Jupiter Model
Wahl, Sean M.; Hubbard, William B.; Militzer, Burkhard
2016-11-01
In anticipation of improved observational data for Jupiter’s gravitational field, from the Juno spacecraft, we predict the static tidal response for a variety of Jupiter interior models based on ab initio computer simulations of hydrogen-helium mixtures. We calculate hydrostatic-equilibrium gravity terms, using the non-perturbative concentric Maclaurin Spheroid method that eliminates lengthy expansions used in the theory of figures. Our method captures terms arising from the coupled tidal and rotational perturbations, which we find to be important for a rapidly rotating planet like Jupiter. Our predicted static tidal Love number, {k}2=0.5900, is ˜10% larger than previous estimates. The value is, as expected, highly correlated with the zonal harmonic coefficient J 2, and is thus nearly constant when plausible changes are made to the interior structure while holding J 2 fixed at the observed value. We note that the predicted static k 2 might change, due to Jupiter’s dynamical response to the Galilean moons, and find reasons to argue that the change may be detectable—although we do not present here a theory of dynamical tides for highly oblate Jovian planets. An accurate model of Jupiter’s tidal response will be essential for interpreting Juno observations and identifying tidal signals from effects of other interior dynamics of Jupiter’s gravitational field.
Preliminary results of steel containment vessel model test
Energy Technology Data Exchange (ETDEWEB)
Luk, V.K.; Hessheimer, M.F. [Sandia National Labs., Albuquerque, NM (United States); Matsumoto, T.; Komine, K.; Arai, S. [Nuclear Power Engineering Corp., Tokyo (Japan); Costello, J.F. [Nuclear Regulatory Commission, Washington, DC (United States)
1998-04-01
A high pressure test of a mixed-scaled model (1:10 in geometry and 1:4 in shell thickness) of a steel containment vessel (SCV), representing an improved boiling water reactor (BWR) Mark II containment, was conducted on December 11--12, 1996 at Sandia National Laboratories. This paper describes the preliminary results of the high pressure test. In addition, the preliminary post-test measurement data and the preliminary comparison of test data with pretest analysis predictions are also presented.
Preliminary study on CAD-based method of characteristics for neutron transport calculation
Chen, Zhen-Ping; Sun, Guang-Yao; Song, Jing; Hao, Li-Juan; Hu, Li-Qin; Wu, Yi-Can
2013-01-01
The method of characteristics (MOC) is widely used for neutron transport calculation in recent decades. However, the key problem determining whether MOC can be applied in highly heterogeneous geometry is how to combine an effective geometry modeling method with it. Most of the existing MOC codes conventionally describe the geometry model just by lines and arcs with extensive input data. Thus they have difficulty in geometry modeling and ray tracing for complicated geometries. In this study, a new method making use of a CAD-based automatic modeling tool MCAM which is a CAD/Image-based Automatic Modeling Program for Neutronics and Radiation Transport developed by FDS Team in China was introduced for geometry modeling and ray tracing of particle transport to remove those limitations. The diamond -difference scheme was applied to MOC to reduce the spatial discretization errors of the flat flux approximation. Based on MCAM and MOC, a new MOC code was developed and integrated into SuperMC system, whic h is a Super ...
Preliminary Development of Thermal Power Calculation Code H-Power for a Supercritical Water Reactor
Directory of Open Access Journals (Sweden)
Fan Zhang
2014-01-01
Full Text Available SCWR (Supercritical Water Reactor is one of the promising Generation IV nuclear systems, which has higher thermal power efficiency than current pressurized water reactor. It is necessary to perform the thermal equilibrium and thermal power calculation for the conceptual design and further monitoring and calibration of the SCWR. One visual software named H-Power was developed to calculate thermal power and its uncertainty of SCWR, in which the advanced IAPWS-IF97 industrial formulation was used to calculate the thermodynamic properties of water and steam. The ISO-5167-4: 2003 standard was incorporated in the code as the basis of orifice plate to compute the flow rate. New heat balance model and uncertainty estimate have also been included in the code. In order to validate H-Power, an assessment was carried out by using data published by US and Qinshan Phase II. The results showed that H-Power was able to estimate the thermal power of SCWR.
Outline and Preliminary Evaluation of the Classical Digital Library Model.
MacCall, Steven L.; Cleveland, Ana D.; Gibson, Ian E.
1999-01-01
Outlines the classical digital library model, which is derived from traditional practices of library and information science professionals, as an alternative to the database retrieval model. Reports preliminary results from an evaluation study of library and information professionals and endusers involved with primary care medicine. (AEF)
A preliminary model of the coma of 2060 Chiron
Boice, Daniel C.; Konno, I.; Stern, S. Alan; Huebner, Walter F.
1992-01-01
We have included gravity in our fluid dynamic model with chemical kinetics of dusty comet comae and applied it with two dust sizes to 2060 Chiron. A progress report on the model and preliminary results concerning gas/dust dynamics and chemistry is given.
Thermochemical data for CVD modeling from ab initio calculations
Energy Technology Data Exchange (ETDEWEB)
Ho, P. [Sandia National Labs., Albuquerque, NM (United States); Melius, C.F. [Sandia National Labs., Livermore, CA (United States)
1993-12-31
Ab initio electronic-structure calculations are combined with empirical bond-additivity corrections to yield thermochemical properties of gas-phase molecules. A self-consistent set of heats of formation for molecules in the Si-H, Si-H-Cl, Si-H-F, Si-N-H and Si-N-H-F systems is presented, along with preliminary values for some Si-O-C-H species.
Uncertainty calculation in transport models and forecasts
DEFF Research Database (Denmark)
Manzo, Stefano; Prato, Carlo Giacomo
in a four-stage transport model related to different variable distributions (to be used in a Monte Carlo simulation procedure), assignment procedures and levels of congestion, at both the link and the network level. The analysis used as case study the Næstved model, referring to the Danish town of Næstved2...... the uncertainty propagation pattern over time specific for key model outputs becomes strategically important. 1 Manzo, S., Nielsen, O. A. & Prato, C. G. (2014). The Effects of uncertainty in speed-flow curve parameters on a large-scale model. Transportation Research Record, 1, 30-37. 2 Manzo, S., Nielsen, O. A...
Preliminary Multivariable Cost Model for Space Telescopes
Stahl, H. Philip
2010-01-01
Parametric cost models are routinely used to plan missions, compare concepts and justify technology investments. Previously, the authors published two single variable cost models based on 19 flight missions. The current paper presents the development of a multi-variable space telescopes cost model. The validity of previously published models are tested. Cost estimating relationships which are and are not significant cost drivers are identified. And, interrelationships between variables are explored
Modeling Malaysia's Energy System: Some Preliminary Results
Ahmad M. Yusof
2011-01-01
Problem statement: The current dynamic and fragile world energy environment necessitates the development of new energy model that solely caters to analyze Malaysias energy scenarios. Approach: The model is a network flow model that traces the flow of energy carriers from its sources (import and mining) through some conversion and transformation processes for the production of energy products to final destinations (energy demand sectors). The integration to the economic sectors is done exogene...
Quantum biological channel modeling and capacity calculation.
Djordjevic, Ivan B
2012-12-10
Quantum mechanics has an important role in photosynthesis, magnetoreception, and evolution. There were many attempts in an effort to explain the structure of genetic code and transfer of information from DNA to protein by using the concepts of quantum mechanics. The existing biological quantum channel models are not sufficiently general to incorporate all relevant contributions responsible for imperfect protein synthesis. Moreover, the problem of determination of quantum biological channel capacity is still an open problem. To solve these problems, we construct the operator-sum representation of biological channel based on codon basekets (basis vectors), and determine the quantum channel model suitable for study of the quantum biological channel capacity and beyond. The transcription process, DNA point mutations, insertions, deletions, and translation are interpreted as the quantum noise processes. The various types of quantum errors are classified into several broad categories: (i) storage errors that occur in DNA itself as it represents an imperfect storage of genetic information, (ii) replication errors introduced during DNA replication process, (iii) transcription errors introduced during DNA to mRNA transcription, and (iv) translation errors introduced during the translation process. By using this model, we determine the biological quantum channel capacity and compare it against corresponding classical biological channel capacity. We demonstrate that the quantum biological channel capacity is higher than the classical one, for a coherent quantum channel model, suggesting that quantum effects have an important role in biological systems. The proposed model is of crucial importance towards future study of quantum DNA error correction, developing quantum mechanical model of aging, developing the quantum mechanical models for tumors/cancer, and study of intracellular dynamics in general.
Quantum Biological Channel Modeling and Capacity Calculation
Directory of Open Access Journals (Sweden)
Ivan B. Djordjevic
2012-12-01
Full Text Available Quantum mechanics has an important role in photosynthesis, magnetoreception, and evolution. There were many attempts in an effort to explain the structure of genetic code and transfer of information from DNA to protein by using the concepts of quantum mechanics. The existing biological quantum channel models are not sufficiently general to incorporate all relevant contributions responsible for imperfect protein synthesis. Moreover, the problem of determination of quantum biological channel capacity is still an open problem. To solve these problems, we construct the operator-sum representation of biological channel based on codon basekets (basis vectors, and determine the quantum channel model suitable for study of the quantum biological channel capacity and beyond. The transcription process, DNA point mutations, insertions, deletions, and translation are interpreted as the quantum noise processes. The various types of quantum errors are classified into several broad categories: (i storage errors that occur in DNA itself as it represents an imperfect storage of genetic information, (ii replication errors introduced during DNA replication process, (iii transcription errors introduced during DNA to mRNA transcription, and (iv translation errors introduced during the translation process. By using this model, we determine the biological quantum channel capacity and compare it against corresponding classical biological channel capacity. We demonstrate that the quantum biological channel capacity is higher than the classical one, for a coherent quantum channel model, suggesting that quantum effects have an important role in biological systems. The proposed model is of crucial importance towards future study of quantum DNA error correction, developing quantum mechanical model of aging, developing the quantum mechanical models for tumors/cancer, and study of intracellular dynamics in general.
Milky Way Mass Models for Orbit Calculations
Irrgang, Andreas; Tucker, Evan; Schiefelbein, Lucas
2013-01-01
Studying the trajectories of objects like stars, globular clusters or satellite galaxies in the Milky Way allows to trace the dark matter halo but requires reliable models of its gravitational potential. Realistic, yet simple and fully analytical models have already been presented in the past. However, improved as well as new observational constraints have become available in the meantime calling for a recalibration of the respective model parameters. Three widely used model potentials are revisited. By a simultaneous least-squared fit to the observed rotation curve, in-plane proper motion of Sgr A*, local mass/surface density and the velocity dispersion in Baade's window, parameters of the potentials are brought up-to-date. The mass at large radii - and thus in particular that of the dark matter halo - is hereby constrained by imposing that the most extreme halo blue horizontal-branch star known has to be bound to the Milky Way. The Galactic mass models are tuned to yield a very good match to recent observat...
Renormalization-group calculation of excitation properties for impurity models
Yoshida, M.; Whitaker, M. A.; Oliveira, L. N.
1990-05-01
The renormalization-group method developed by Wilson to calculate thermodynamical properties of dilute magnetic alloys is generalized to allow the calculation of dynamical properties of many-body impurity Hamiltonians. As a simple illustration, the impurity spectral density for the resonant-level model (i.e., the U=0 Anderson model) is computed. As a second illustration, for the same model, the longitudinal relaxation rate for a nuclear spin coupled to the impurity is calculated as a function of temperature.
Modeling method and preliminary model of Asteroid Toutatis from Chang'E-2 optical images
Li, Xiang-Yu; Qiao, Dong
2014-06-01
Shape modeling is fundamental to the analysis of dynamic environment and motion around asteroid. Chang'E-2 successfully made a flyby of Asteroid 4179 Toutatis and obtained plenty of high-resolution images during the mission. In this paper, the modeling method and preliminary model of Asteroid Toutatis are discussed. First, the optical images obtained by Chang'E-2 are analyzed. Terrain and silhouette features in images are described. Then, the modeling method based on previous radar model and preliminary information from optical images is proposed. A preliminary polyhedron model of Asteroid Toutatis is established. Finally, the spherical harmonic coefficients of Asteroid Toutatis based on the polyhedron model are obtained. Some parameters of model are analyzed and compared. Although the model proposed in this paper is only a preliminary model, this work offers a valuable reference for future high-resolution models.
Detailed opacity calculations for stellar models
Pain, Jean-Christophe; Gilleron, Franck
2016-10-01
We present a state of the art of precise spectral opacity calculations illustrated by stellar applications. The essential role of laboratory experiments to check the quality of the computed data is underlined. We review some X-ray and XUV laser and Z-pinch photo-absorption measurements as well as X-ray emission spectroscopy experiments of hot dense plasmas produced by ultra-high-intensity laser interaction. The measured spectra are systematically compared with the fine-structure opacity code SCO-RCG. Focus is put on iron, due to its crucial role in the understanding of asteroseismic observations of Beta Cephei-type and Slowly Pulsating B stars, as well as in the Sun. For instance, in Beta Cephei-type stars (which should not be confused with Cepheid variables), the iron-group opacity peak excites acoustic modes through the kappa-mechanism. A particular attention is paid to the higher-than-predicted iron opacity measured on Sandia's Z facility at solar interior conditions (boundary of the convective zone). We discuss some theoretical aspects such as orbital relaxation, electron collisional broadening, ionic Stark effect, oscillator-strength sum rules, photo-ionization, or the ``filling-the-gap'' effect of highly excited states.
Energy Technology Data Exchange (ETDEWEB)
Smith, F.
2012-08-06
At the request of Savannah River Remediation (SRR), SRNL has analyzed the expected performance obtained from using seven 32 million gallon Saltstone Disposal Units (SDUs) in the Z-Area Saltstone Disposal Facility (SDF) to store future saltstone grout. The analysis was based on preliminary SDU final design specifications. The analysis used PORFLOW modeling to calculate the release of 20 radionuclides from an SDU and transport of the radionuclides and daughters through the vadose zone. Results from this vadose zone analysis were combined with previously calculated releases from existing saltstone vaults and FDCs and a second PORFLOW model run to calculate aquifer transport to assessment points located along a boundary 100 m from the nearest edge of the SDF sources. Peak concentrations within 12 sectors spaced along the 100 m boundary were determined over a period of evaluation extending 20,000 years after SDF closure cap placement. These peak concentrations were provided to SRR to use as input for dose calculations.
Utility of Social Modeling for Proliferation Assessment - Preliminary Assessment
Energy Technology Data Exchange (ETDEWEB)
Coles, Garill A.; Gastelum, Zoe N.; Brothers, Alan J.; Thompson, Sandra E.
2009-06-01
This Preliminary Assessment draft report will present the results of a literature search and preliminary assessment of the body of research, analysis methods, models and data deemed to be relevant to the Utility of Social Modeling for Proliferation Assessment research. This report will provide: 1) a description of the problem space and the kinds of information pertinent to the problem space, 2) a discussion of key relevant or representative literature, 3) a discussion of models and modeling approaches judged to be potentially useful to the research, and 4) the next steps of this research that will be pursued based on this preliminary assessment. This draft report represents a technical deliverable for the NA-22 Simulations, Algorithms, and Modeling (SAM) program. Specifically this draft report is the Task 1 deliverable for project PL09-UtilSocial-PD06, Utility of Social Modeling for Proliferation Assessment. This project investigates non-traditional use of social and cultural information to improve nuclear proliferation assessment, including nonproliferation assessment, proliferation resistance assessments, safeguards assessments and other related studies. These assessments often use and create technical information about the State’s posture towards proliferation, the vulnerability of a nuclear energy system to an undesired event, and the effectiveness of safeguards. This project will find and fuse social and technical information by explicitly considering the role of cultural, social and behavioral factors relevant to proliferation. The aim of this research is to describe and demonstrate if and how social science modeling has utility in proliferation assessment.
Model calculation of thermal conductivity in antiferromagnets
Energy Technology Data Exchange (ETDEWEB)
Mikhail, I.F.I., E-mail: ifi_mikhail@hotmail.com; Ismail, I.M.M.; Ameen, M.
2015-11-01
A theoretical study is given of thermal conductivity in antiferromagnetic materials. The study has the advantage that the three-phonon interactions as well as the magnon phonon interactions have been represented by model operators that preserve the important properties of the exact collision operators. A new expression for thermal conductivity has been derived that involves the same terms obtained in our previous work in addition to two new terms. These two terms represent the conservation and quasi-conservation of wavevector that occur in the three-phonon Normal and Umklapp processes respectively. They gave appreciable contributions to the thermal conductivity and have led to an excellent quantitative agreement with the experimental measurements of the antiferromagnet FeCl{sub 2}. - Highlights: • The Boltzmann equations of phonons and magnons in antiferromagnets have been studied. • Model operators have been used to represent the magnon–phonon and three-phonon interactions. • The models possess the same important properties as the exact operators. • A new expression for the thermal conductivity has been derived. • The results showed a good quantitative agreement with the experimental data of FeCl{sub 2}.
A preliminary model to avoid the overestimation of sample size in bioequivalence studies.
Ramírez, E; Abraira, V; Guerra, P; Borobia, A M; Duque, B; López, J L; Mosquera, B; Lubomirov, R; Carcas, A J; Frías, J
2013-02-01
Often the only available data in literature for sample size estimations in bioequivalence studies is intersubject variability, which tends to result in overestimation of sample size. In this paper, we proposed a preliminary model of intrasubject variability based on intersubject variability for Cmax and AUC data from randomized, crossovers, bioequivalence (BE) studies. From 93 Cmax and 121 AUC data from test-reference comparisons that fulfilled BE criteria, we calculated intersubject variability for the reference formulation and intrasubject variability from ANOVA. Lineal and exponential models (y=a(1-e-bx)) were fitted weighted by the inverse of the variance, to predict the intrasubject variability based on intersubject variability. To validate the model we calculated the coefficient of cross-validation of data from 30 new BE studies. The models fit very well (R2=0.997 and 0.990 for Cmax and AUC respectively) and the cross-validation correlation were 0.847 for Cmax and 0.572 for AUC. A preliminary model analyses allow us to estimate the intrasubject variability based on intersubject variability for sample size calculation purposes in BE studies. This approximation provides an opportunity for sample size reduction avoiding unnecessary exposure of healthy volunteers. Further modelling studies are desirable to confirm these results especially suggestions of the higher intersubject variability range.
A preliminary deposit model for lithium brines
Bradley, Dwight; Munk, LeeAnn; Jochens, Hillary; Hynek, Scott; Labay, Keith A.
2013-01-01
This report is part of an effort by the U.S. Geological Survey to update existing mineral deposit models and to develop new ones. The global transition away from hydrocarbons toward energy alternatives increases demand for many scarce metals. Among these is lithium, a key component of lithium-ion batteries for electric and hybrid vehicles. Lithium brine deposits account for about three-fourths of the world’s lithium production. Updating an earlier deposit model, we emphasize geologic information that might directly or indirectly help in exploration for lithium brine deposits, or for assessing regions for mineral resource potential. Special attention is given to the best-known deposit in the world—Clayton Valley, Nevada, and to the giant Salar de Atacama, Chile.
Preliminary Model of Acute Mountain Sickness Severity
2010-10-01
variance, the Akaike information criterion (AIC) and Bayesian information criterion (BIC) were utilized in selecting the final model using the... information and completed an Environmental Symptoms Questionnaire (ESQ). The ESQ assessed AMS severity using the validated AMS-Cerebral (AMS-C) factor...reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching
Shell model calculations of 109Sb in the sdgh shell
Dikmen, E.; Novoselsky, A.; Vallieres, M.
2001-12-01
The energy spectra of the antimony isotope 109Sb in the sdgh shell are calculated in the nuclear shell model approach by using the CD-Bonn nucleon-nucleon interaction. The modified Drexel University parallel shell model code (DUPSM) was used for the calculations with maximum Hamiltonian dimension of 762 253 of 5.14% sparsity. The energy levels are compared to the recent experimental results. The calculations were done on the Cyborg Parallel Cluster System at Drexel University.
[Calculation of parameters in forest evapotranspiration model].
Wang, Anzhi; Pei, Tiefan
2003-12-01
Forest evapotranspiration is an important component not only in water balance, but also in energy balance. It is a great demand for the development of forest hydrology and forest meteorology to simulate the forest evapotranspiration accurately, which is also a theoretical basis for the management and utilization of water resources and forest ecosystem. Taking the broadleaved Korean pine forest on Changbai Mountain as an example, this paper constructed a mechanism model for estimating forest evapotranspiration, based on the aerodynamic principle and energy balance equation. Using the data measured by the Routine Meteorological Measurement System and Open-Path Eddy Covariance Measurement System mounted on the tower in the broadleaved Korean pine forest, the parameters displacement height d, stability functions for momentum phi m, and stability functions for heat phi h were ascertained. The displacement height of the study site was equal to 17.8 m, near to the mean canopy height, and the functions of phi m and phi h changing with gradient Richarson number R i were constructed.
Swartjes F; ECO
2003-01-01
Twenty scenarios, differing with respect to land use, soil type and contaminant, formed the basis for calculating human exposure from soil contaminants with the use of models contributed by seven European countries (one model per country). Here, the human exposures to children and children
Modeling and Testing of EVs - Preliminary Study and Laboratory Development
DEFF Research Database (Denmark)
Yang, Guang-Ya; Marra, Francesco; Nielsen, Arne Hejde
2010-01-01
impact at different geographical areas, as well as driving and charging patterns. Electric circuit model is deployed in this work to represent the electrical properties of a lithium-ion battery. This paper reports the preliminary modeling and validation work based on manufacturer data sheet and realistic......Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid...... tests, followed by the suggestions towards a feasible battery model for further studies....
Energy Technology Data Exchange (ETDEWEB)
Baguena, A.; Shaw, M.; Williart, A. [Universidad Nacional de Educacion a Distancia, Dpto. Fisica de los Materiales, Madrid (Spain); Baguena, A. [Consejo de Seguridad Nuclear, Madrid (Spain); Garcia, G. [Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Madrid (Spain)
2006-07-01
We describe the calculations and preliminary measures made for the installation of a X-ray generator tube. This device is going to be used for the secondary electron production from photonic primary radiation of up to 125 keV. With this experimental system, we will study the energetic and space distribution of produced secondary electrons by obtaining its spectrum of energies and its angular distribution. This method of measurement is going to be applied in different targets of radiological, environmental and biological interest. Calculations in the present article include: theoretical yield of X-rays production of the designed equipment, necessary shielding for the radiological safety of the installation staff, and an estimated dose due to their use. Characteristics of the installation and the equipment are described with this purpose. (author)
Preliminary Study on the Calculation Method of “Carbon Footprint”
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
At present, greenhouse effect has become a severe challenge of international society. In order to cope with this challenge, countries all over the world reached an agreement to develop low-carbon economy and create low-carbon society. As a new concept, "carbon footprint" emerged with the vigorous development of low-carbon economy, and its calculation method is related to the evaluation system of low carbon economy. In order to calculate "carbon footprint", "carbon subject" in the study was divided into ener...
A methodology for constructing the calculation model of scientific spreadsheets
Vos, de, Ans; Wielemaker, J.; Schreiber, G.; Wielinga, B.; Top, J.L.
2015-01-01
Spreadsheets models are frequently used by scientists to analyze research data. These models are typically described in a paper or a report, which serves as single source of information on the underlying research project. As the calculation workflow in these models is not made explicit, readers are not able to fully understand how the research results are calculated, and trace them back to the underlying spreadsheets. This paper proposes a methodology for semi-automatically deriving the calcu...
Modeling huge sound sources in a room acoustical calculation program
DEFF Research Database (Denmark)
Christensen, Claus Lynge
1999-01-01
A room acoustical model capable of modeling point sources, line sources, and surface sources is presented. Line and surface sources are modeled using a special ray-tracing algorithm detecting the radiation pattern of the surfaces of the room. Point sources are modeled using a hybrid calculation...... method combining this ray-tracing method with image source modeling. With these three source types it is possible to model huge and complex sound sources in industrial environments. Compared to a calculation with only point sources, the use of extended sound sources is shown to improve the agreement...
Modeling Large sound sources in a room acoustical calculation program
DEFF Research Database (Denmark)
Christensen, Claus Lynge
1999-01-01
A room acoustical model capable of modelling point, line and surface sources is presented. Line and surface sources are modelled using a special ray-tracing algorithm detecting the radiation pattern of the surfaces in the room. Point sources are modelled using a hybrid calculation method combining...... this ray-tracing method with Image source modelling. With these three source types, it is possible to model large and complex sound sources in workrooms....
Modeling Large sound sources in a room acoustical calculation program
DEFF Research Database (Denmark)
Christensen, Claus Lynge
1999-01-01
A room acoustical model capable of modelling point, line and surface sources is presented. Line and surface sources are modelled using a special ray-tracing algorithm detecting the radiation pattern of the surfaces in the room. Point sources are modelled using a hybrid calculation method combining...... this ray-tracing method with Image source modelling. With these three source types, it is possible to model large and complex sound sources in workrooms....
Campbell, David L.; Watts, Raymond D.
1978-01-01
Program listing, instructions, and example problems are given for 12 programs for the interpretation of geophysical data, for use on Hewlett-Packard models 67 and 97 programmable hand-held calculators. These are (1) gravity anomaly over 2D prism with = 9 vertices--Talwani method; (2) magnetic anomaly (?T, ?V, or ?H) over 2D prism with = 8 vertices?Talwani method; (3) total-field magnetic anomaly profile over thick sheet/thin dike; (4) single dipping seismic refractor--interpretation and design; (5) = 4 dipping seismic refractors--interpretation; (6) = 4 dipping seismic refractors?design; (7) vertical electrical sounding over = 10 horizontal layers--Schlumberger or Wenner forward calculation; (8) vertical electric sounding: Dar Zarrouk calculations; (9) magnetotelluric planewave apparent conductivity and phase angle over = 9 horizontal layers--forward calculation; (10) petrophysics: a.c. electrical parameters; (11) petrophysics: elastic constants; (12) digital convolution with = 10-1ength filter.
Innovative Product Design Based on Customer Requirement Weight Calculation Model
Institute of Scientific and Technical Information of China (English)
Chen-Guang Guo; Yong-Xian Liu; Shou-Ming Hou; Wei Wang
2010-01-01
In the processes of product innovation and design, it is important for the designers to find and capture customer's focus through customer requirement weight calculation and ranking. Based on the fuzzy set theory and Euclidean space distance, this paper puts forward a method for customer requirement weight calculation called Euclidean space distances weighting ranking method. This method is used in the fuzzy analytic hierarchy process that satisfies the additive consistent fuzzy matrix. A model for the weight calculation steps is constructed;meanwhile, a product innovation design module on the basis of the customer requirement weight calculation model is developed. Finally, combined with the instance of titanium sponge production, the customer requirement weight calculation model is validated. By the innovation design module, the structure of the titanium sponge reactor has been improved and made innovative.
Modeling the connection between development and evolution: Preliminary report
Energy Technology Data Exchange (ETDEWEB)
Mjolsness, E.; Reinitz, J. [Yale Univ., New Haven, CT (United States); Garrett, C.D. [Washington Univ., Seattle, WA (United States). Dept. of Computer Science; Sharp, D.H. [Los Alamos National Lab., NM (United States)
1993-07-29
In this paper we outline a model which incorporates development processes into an evolutionary frame work. The model consists of three sectors describing development, genetics, and the selective environment. The formulation of models governing each sector uses dynamical grammars to describe processes in which state variables evolve in a quantitative fashion, and the number and type of participating biological entities can change. This program has previously been elaborated for development. Its extension to the other sectors of the model is discussed here and forms the basis for further approximations. A specific implementation of these ideas is described for an idealized model of the evolution of a multicellular organism. While this model doe not describe an actual biological system, it illustrates the interplay of development and evolution. Preliminary results of numerical simulations of this idealized model are presented.
Calculation of Al-Zn diagram from central atoms model
Institute of Scientific and Technical Information of China (English)
无
1999-01-01
A slightly modified central atoms model was proposed. The probabilities of various clusters with the central atoms and their nearest neighboring shells can be calculated neglecting the assumption of the param eter of energy in the central atoms model in proportion to the number of other atoms i (referred with the central atom). A parameter Pα is proposed in this model, which equals to reciprocal of activity coefficient of a component, therefore, the new model can be understood easily. By this model, the Al-Zn phase diagram and its thermodynamic properties were calculated, the results coincide with the experimental data.
New Calculations in Dirac Gaugino Models: Operators, Expansions, and Effects
Carpenter, Linda M
2015-01-01
In this work we calculate important one loop SUSY-breaking parameters in models with Dirac gauginos, which are implied by the existence of heavy messenger fields. We find that these SUSY-breaking effects are all related by a small number of parameters, thus the general theory is tightly predictive. In order to make the most accurate analyses of one loop effects, we introduce calculations using an expansion in SUSY breaking messenger mass, rather than relying on postulating the forms of effective operators. We use this expansion to calculate one loop contributions to gaugino masses, non-holomorphic SM adjoint masses, new A-like and B-like terms, and linear terms. We also test the Higgs potential in such models, and calculate one loop contributions to the Higgs mass in certain limits of R-symmetric models, finding a very large contribution in many regions of the $\\mu$-less MSSM, where Higgs fields couple to standard model adjoint fields.
Modeling and Calculator Tools for State and Local Transportation Resources
Air quality models, calculators, guidance and strategies are offered for estimating and projecting vehicle air pollution, including ozone or smog-forming pollutants, particulate matter and other emissions that pose public health and air quality concerns.
Modelling Large sound sources in a room acoustical calculation program
DEFF Research Database (Denmark)
Christensen, Claus Lynge
1999-01-01
A room acoustical model capable of modelling point, line and surface sources is presented. Line and surfacesources are modelled using a special ray-tracing algorithm detecting the radiation pattern of the surfaces in the room.Point sources are modelled using a hybrid calculation method combining...... this ray-tracing method with Image sourcemodelling. With these three source types, it is possible to model large and complex sound sources in workrooms....
Modelling Large sound sources in a room acoustical calculation program
DEFF Research Database (Denmark)
Christensen, Claus Lynge
1999-01-01
A room acoustical model capable of modelling point, line and surface sources is presented. Line and surfacesources are modelled using a special ray-tracing algorithm detecting the radiation pattern of the surfaces in the room.Point sources are modelled using a hybrid calculation method combining...... this ray-tracing method with Image sourcemodelling. With these three source types, it is possible to model large and complex sound sources in workrooms....
COMPARISON BETWEEN MODELS FOR CALCULATION OF INDUSTRIAL HOT ROLLING LOADS
Antonio Augusto Gorni; Marcos Roberto Soares da Silva
2012-01-01
An evaluation is made about the precision of hot strip rolling mill loads at the F1 stand calculated according to the theoretical models of Orowan, Sims, Alexander-Ford, Orowan-Pascoe, Ekelund and Tselikov in comparison to real values got for carbon-manganese steels. In the deterministic approach, without any fit of the calculated values to real data, Orowan, Sims and Alexander-Models show best levels of precision, as expected from the information got in the literature. However, i...
Calculation of Thermodynamic Parameters for Freundlich and Temkin Isotherm Models
Institute of Scientific and Technical Information of China (English)
ZHANGZENGQIANG; ZHANGYIPING; 等
1999-01-01
Derivation of the Freundlich and Temkin isotherm models from the kinetic adsorption/desorption equations was carried out to calculate their thermodynamic equilibrium constants.The calculation formulase of three thermodynamic parameters,the standard molar Gibbs free energy change,the standard molar enthalpy change and the standard molar entropy change,of isothermal adsorption processes for Freundlich and Temkin isotherm models were deduced according to the relationship between the thermodynamic equilibrium constants and the temperature.
Effective UV radiation from model calculations and measurements
Feister, Uwe; Grewe, Rolf
1994-01-01
Model calculations have been made to simulate the effect of atmospheric ozone and geographical as well as meteorological parameters on solar UV radiation reaching the ground. Total ozone values as measured by Dobson spectrophotometer and Brewer spectrometer as well as turbidity were used as input to the model calculation. The performance of the model was tested by spectroradiometric measurements of solar global UV radiation at Potsdam. There are small differences that can be explained by the uncertainty of the measurements, by the uncertainty of input data to the model and by the uncertainty of the radiative transfer algorithms of the model itself. Some effects of solar radiation to the biosphere and to air chemistry are discussed. Model calculations and spectroradiometric measurements can be used to study variations of the effective radiation in space in space time. The comparability of action spectra and their uncertainties are also addressed.
COMPARISON BETWEEN MODELS FOR CALCULATION OF INDUSTRIAL HOT ROLLING LOADS
Directory of Open Access Journals (Sweden)
Antonio Augusto Gorni
2012-09-01
Full Text Available An evaluation is made about the precision of hot strip rolling mill loads at the F1 stand calculated according to the theoretical models of Orowan, Sims, Alexander-Ford, Orowan-Pascoe, Ekelund and Tselikov in comparison to real values got for carbon-manganese steels. In the deterministic approach, without any fit of the calculated values to real data, Orowan, Sims and Alexander-Models show best levels of precision, as expected from the information got in the literature. However, in the semi-empirical approach, after a linear fit between calculated values and real data, Tselikov and Ekelund models show better adequacy to the industrial data, a fact that can be attributed to more significant errors occurring in the sub-models of temperature, tribology and hot strength than in the rolling load models. For its turn, neural network models show the best levels of precision which make very attractive the adoption of this approach.
Preliminary Calculations of Shutdown Dose Rate for the CTS Diagnostics System
DEFF Research Database (Denmark)
Klinkby, Esben Bryndt; Nonbøl, Erik; Lauritzen, Bent
2015-01-01
DTU and IST 2 are partners in the design of a collective Thomson Scattering (CTS) diagnostics for ITER through a contract with F4E. The CTS diagnostic utilizes probing radiation of ~60 GHz emitted into the plasma and, using a mirror, collects the scattered radiation by an array of receivers. Having...... a direct and unshielded view to the plasma, the first mirror will be subject to significant radiation and among the first tasks in the CTS design, is to determine whether the mirror will need active cooling. At present the CTS is in the conceptual design phase and the related neutronics calculations focus...
Mathematical modeling of normal pharyngeal bolus transport: a preliminary study.
Chang, M W; Rosendall, B; Finlayson, B A
1998-07-01
Dysphagia (difficulty in swallowing) is a common clinical symptom associated with many diseases, such as stroke, multiple sclerosis, neuromuscular diseases, and cancer. Its complications include choking, aspiration, malnutrition, cachexia, and dehydration. The goal in dysphagia management is to provide adequate nutrition and hydration while minimizing the risk of choking and aspiration. It is important to advance the individual toward oral feeding in a timely manner to enhance the recovery of swallowing function and preserve the quality of life. Current clinical assessments of dysphagia are limited in providing adequate guidelines for oral feeding. Mathematical modeling of the fluid dynamics of pharyngeal bolus transport provides a unique opportunity for studying the physiology and pathophysiology of swallowing. Finite element analysis (FEA) is a special case of computational fluid dynamics (CFD). In CFD, the flow of a fluid in a space is modeled by covering the space with a grid and predicting how the fluid moves from grid point to grid point. FEA is capable of solving problems with complex geometries and free surfaces. A preliminary pharyngeal model has been constructed using FEA. This model incorporates literature-reported, normal, anatomical data with time-dependent pharyngeal/upper esophageal sphincter (UES) wall motion obtained from videofluorography (VFG). This time-dependent wall motion can be implemented as a moving boundary condition in the model. Clinical kinematic data can be digitized from VFG studies to construct and test the mathematical model. The preliminary model demonstrates the feasibility of modeling pharyngeal bolus transport, which, to our knowledge, has not been attempted before. This model also addresses the need and the potential for CFD in understanding the physiology and pathophysiology of the pharyngeal phase of swallowing. Improvements of the model are underway. Combining the model with individualized clinical data should potentially
Preliminary Calculation of the EROI for the Production of Gas in Russia
Directory of Open Access Journals (Sweden)
Roman Nogovitsyn
2014-09-01
Full Text Available Russia is one of the world’s largest producers of energy resources. Production of energy resources in Russia is profitable, both economically and in terms of the energy produced (as measured by EROI. At the present time, Russian oil and gas companies have a policy of energy saving, and data on energy consumption is given in annual reports. Based on these data, we can make the EROI calculation. In 2013, the EROI for the production, transportation and processing of gas for Open joint stock company (OJSC “Gazprom” was 79:1; for OJSC “NOVATEK”, 76:1; for OJSC “Yakutsk Fuel and Energy Company (YATEC”, only for production, 116:1. Currently, the situation in the oil and gas industry has come to a point when there is a need for the introduction of an energy audit.
Study on neural network model for calculating subsidence factor
Institute of Scientific and Technical Information of China (English)
GUO Wen-bing; ZHANG Jie
2007-01-01
The major factors influencing subsidence factor were comprehensively analyzed. Then the artificial neural network model for calculating subsidence factor was set up with the theory of artificial neural network (ANN). A large amount of data from observation stations in China was collected and used as learning and training samples to train and test the artificial neural network model. The calculated results of the ANN model and the observed values were compared and analyzed in this paper. The results demonstrate that many factors can be considered in this model and the result is more precise and closer to observed values to calculate the subsidence factor by the ANN model. It can satisfy the need of engineering.
Preliminary Analysis on Distribution Calculation of Elevator%电梯配电计算初析
Institute of Scientific and Technical Information of China (English)
谢宁
2014-01-01
以电机采用蜗轮蜗杆传动方式的一般电梯为例，提出电梯配电设计的功率应以满载时电功率转换为机械功率的传动功率为依据。对配置一般起重用（绕线转子异步）电动机为动力的曳引机的电梯主回路供电，提出配电计算思路。同时论述电动机铭牌功率和按需要系数法得出的功率，都不能真实反映电梯电功率和机械功率的能量关系。%A common elevator characterized in that the motor adopts worm-gear transmission is taken as an example, based on that the power of the elevator distribution design shall be the transmission power for converting the electrical power into the mechanical power under full load, a distribution calculation idea is proposed for power supply to the main circuit of the elevator with a general crane motor (asynchronous wound-rotor) as dynamic tractor. Besides, the rated power and the power calculated by demand factor method are discussed, both of which are unable to truly reflect the energy relationship between the electrical power and the mechanical power of the elevator.
A MODEL OF FUZZY CALCULATION OF THE CONSTUCTION COST
Institute of Scientific and Technical Information of China (English)
邵良杉; 叶景楼; 李东
1998-01-01
An overview of the delelopment of approaches to construction cost and price forcasting since the 1950's is given. First, second and third generation models can be identified, but they all have shortcomings. This paper puts forward a new model, fuzzy calculation model, based on lots of data of the finished projects. Through actual application, it is proved that the model is accurate and quick in calcalation of construction.
Modeling of overhead transmission lines for lightning overvoltage calculations
Energy Technology Data Exchange (ETDEWEB)
Martinez-Velasco, J.A.; Castro-Aranda, F.
2010-10-15
This article discussed the modelling of overhead transmission lines for lightning overvoltage calculations. Such a model must include those parts of the line that get involved when a lightning return stroke hits a wire or a tower and that have some influence on the voltage developed across insulator strings. Modelling guidelines differ depending on whether the goal is to estimate overvoltages or to determine arrester energy stresses. Modelling guidelines were summarized for each component, including shield wires and phase conductors; transmission line towers; insulators; phase voltages at the instant lightning hits the line; surge arresters; and the lightning stroke. The applied Monte Carlo procedure was summarized. For line span models, a constant-parameter model generally suffices when the goal is to calculate overvoltages across insulators or to obtain the flashover rate, but a frequency-dependent parameter model is necessary to estimate the energy discharged by arresters. The model selected for representing towers can have some influence on both flashover rates and arrester energy stresses. The representation of footing impedances is critical for calculating overvoltages and arrester energy stresses, but different modelling techniques produce significantly different results. The models are limited in that the corona effect is not included in the line models, the voltages induced by the electric and magnetic fields of lightning channels to shield wires and phase conductors are neglected, and the footing models are too simple, but they are nonetheless realistic approaches for simulating lightning effects. 2 tabs., 9 figs.
batman: BAsic Transit Model cAlculatioN in Python
Kreidberg, Laura
2015-11-01
I introduce batman, a Python package for modeling exoplanet transit light curves. The batman package supports calculation of light curves for any radially symmetric stellar limb darkening law, using a new integration algorithm for models that cannot be quickly calculated analytically. The code uses C extension modules to speed up model calculation and is parallelized with OpenMP. For a typical light curve with 100 data points in transit, batman can calculate one million quadratic limb-darkened models in 30 seconds with a single 1.7 GHz Intel Core i5 processor. The same calculation takes seven minutes using the four-parameter nonlinear limb darkening model (computed to 1 ppm accuracy). Maximum truncation error for integrated models is an input parameter that can be set as low as 0.001 ppm, ensuring that the community is prepared for the precise transit light curves we anticipate measuring with upcoming facilities. The batman package is open source and publicly available at https://github.com/lkreidberg/batman .
batman: BAsic Transit Model cAlculatioN in Python
Kreidberg, Laura
2015-01-01
I introduce batman, a Python package for modeling exoplanet transit light curves. The batman package supports calculation of light curves for any radially symmetric stellar limb darkening law, using a new integration algorithm for models that cannot be quickly calculated analytically. The code uses C extension modules to speed up model calculation and is parallelized with OpenMP. For a typical light curve with 100 data points in transit, batman can calculate one million quadratic limb-darkened models in 30 seconds with a single 1.7 GHz Intel Core i5 processor. The same calculation takes seven minutes using the four-parameter nonlinear limb darkening model (computed to 1 ppm accuracy). Maximum truncation error for integrated models is an input parameter that can be set as low as 0.001 ppm, ensuring that the community is prepared for the precise transit light curves we anticipate measuring with upcoming facilities. The batman package is open source and publicly available at https://github.com/lkreidberg/batman.
Preliminary safety calculations to improve the design of Molten Salt Fast Reactor
Energy Technology Data Exchange (ETDEWEB)
Brovchenko, M.; Heuer, D.; Merle-Lucotte, E.; Allibert, M.; Capellan, N.; Ghetta, V.; Laureau, A. [LPSC, CNRS/IN2P3, Grenoble INP, 53,rue des Martyrs, 38026 Grenoble Cedex (France)
2012-07-01
Molten salt reactors are liquid fuel reactors so that they are flexible in operation but very different in the safety approach from solid fuel reactors. This study bears on the specific concept named Molten Salt Fast Reactor (MSFR). Since this new nuclear technology is in development, safety is an essential point to be considered all along the R and D studies. This paper presents the first step of the safety approach: the systematic description of the MSFR, limited here to the main systems surrounding the core. This systematic description is the basis on which we will be able to devise accidental scenarios. Thanks to the negative reactivity feedback coefficient, most accidental scenarios lead to reactor shut down. Because of the decay heat generated in the fuel salt, it must be cooled. After the description of the tools developed to calculate the residual heat, the different contributions are discussed in this study. The decay heat of fission products in the MSFR is evaluated to be low (3% of nominal power), mainly due to the reprocessing that transfers the fission products to the gas reprocessing unit. As a result, the contribution of the actinides is significant (0.5% of nominal power). The unprotected loss of heat sink transients are studied in this paper. It appears that slow transients are favorable (> 1 min) to minimize the temperature increase of the fuel salt. This work will be the basis of further safety studies as well as an essential parameter for the design of the draining system. (authors)
The complete quantum collapse scenario of 2+1 dust shell: Preliminary Calculations
Ortiz, L
2007-01-01
If we consider the gravitational collapse of a material object to a black hole, we would expect, for ranges of mass where a black hole would form, the following scenario. A large enough object would collapse classically until an event horizon forms, and to an external observer the object would be lost fom view. However, once the horizon has formed the black hole will begin to emit Hawking radiation and the hole will lose mass and the horizon will shrink. The final state of this process could be either a zero-mass "black hole" with consequent information loss, or some sort of "quantum remnant. A complete investigation of this process would require: 1) A complete and consistent theory of quantum gravity coupled to some kind of field that would provide the Hawking radiation (which could be the gravitational field itself --gravitons); 2) Some kind of definition of a "horizon" in this quantum gravity, and; 3) The calculational tools to achieve a description of the scenario. Lacking these, one may resort to toy mod...
Statistical Model Calculations for (n,γ Reactions
Directory of Open Access Journals (Sweden)
Beard Mary
2015-01-01
Full Text Available Hauser-Feshbach (HF cross sections are of enormous importance for a wide range of applications, from waste transmutation and nuclear technologies, to medical applications, and nuclear astrophysics. It is a well-observed result that diﬀerent nuclear input models sensitively aﬀect HF cross section calculations. Less well known however are the eﬀects on calculations originating from model-specific implementation details (such as level density parameter, matching energy, back-shift and giant dipole parameters, as well as eﬀects from non-model aspects, such as experimental data truncation and transmission function energy binning. To investigate the eﬀects or these various aspects, Maxwellian-averaged neutron capture cross sections have been calculated for approximately 340 nuclei. The relative eﬀects of these model details will be discussed.
Calculating osmotic pressure according to nonelectrolyte Wilson nonrandom factor model.
Li, Hui; Zhan, Tingting; Zhan, Xiancheng; Wang, Xiaolan; Tan, Xiaoying; Guo, Yiping; Li, Chengrong
2014-08-01
Abstract The osmotic pressure of NaCl solutions was determined by the air humidity in equilibrium (AHE) method. The relationship between the osmotic pressure and the concentration was explored theoretically, and the osmotic pressure was calculated according to the nonelectrolyte Wilson nonrandom factor (N-Wilson-NRF) model from the concentration. The results indicate that the calculated osmotic pressure is comparable to the measured one.
Theoretical Model Calculation for d + 8Li Reaction
Institute of Scientific and Technical Information of China (English)
HAN Yin-Lu; GUO Hai-Rui; ZHANG Yue; ZHANG Jing-Shang
2008-01-01
Based on the theoretical models for light nuclei, the calculations of reaction cross sections and the angular distributions for d+8Li reaction are performed. Since all of the particle emissions are from the compound nucleus to the discrete levels, the angular momentum coupling effect in pre-equilibrium mechanism is taken into account. The three-body break-up process and the recoil effect are involved. The theoretical calculated results are compared to existing experimental data.
Adherence of Model Molecules to Silica Surfaces: First Principle Calculations
Nuñez, Matías; Prado, Miguel Oscar
The adherence of "model molecules" methylene blue and eosine Y ("positive" and "negatively" charged respectively) to crystal SiO2 surfaces is studied from first principle calculations at the DFT level. Adsorption energies are calculated which follow the experimental threads obtained elsewhere (Rivera et al., 2013). We study the quantum nature of the electronic charge transfer between the surface and the molecules, showing the localized and delocalized patterns associated to the repulsive and attractive case respectively.
Calculation of extreme wind atlases using mesoscale modeling. Final report
DEFF Research Database (Denmark)
Larsén, Xiaoli Guo; Badger, Jake
This is the final report of the project PSO-10240 "Calculation of extreme wind atlases using mesoscale modeling". The overall objective is to improve the estimation of extreme winds by developing and applying new methodologies to confront the many weaknesses in the current methodologies...... as explained in Section 2. The focus has been put on developing a number of new methodologies through numerical modeling and statistical modeling....
Qi, Feng; Tavakol, Vahid; Ocket, Ilja; Xu, Peng; Schreurs, Dominique; Wang, Jinkuan; Nauwelaers, Bart
2010-01-01
Active millimeter wave imaging systems have become a promising candidate for indoor security applications and industrial inspection. However, there is a lack of simulation tools at the system level. We introduce and evaluate two modeling approaches that are applied to active millimeter wave imaging systems. The first approach originates in Fourier optics and concerns the calculation in the spatial frequency domain. The second approach is based on wave propagation and corresponds to calculation in the spatial domain. We compare the two approaches in the case of both rough and smooth objects and point out that the spatial frequency domain calculation may suffer from a large error in amplitude of 50% in the case of rough objects. The comparison demonstrates that the concepts of point-spread function and f-number should be applied with careful consideration in coherent millimeter wave imaging systems. In the case of indoor applications, the near-field effect should be considered, and this is included in the spatial domain calculation.
Precipitates/Salts Model Calculations for Various Drift Temperature Environments
Energy Technology Data Exchange (ETDEWEB)
P. Marnier
2001-12-20
The objective and scope of this calculation is to assist Performance Assessment Operations and the Engineered Barrier System (EBS) Department in modeling the geochemical effects of evaporation within a repository drift. This work is developed and documented using procedure AP-3.12Q, Calculations, in support of ''Technical Work Plan For Engineered Barrier System Department Modeling and Testing FY 02 Work Activities'' (BSC 2001a). The primary objective of this calculation is to predict the effects of evaporation on the abstracted water compositions established in ''EBS Incoming Water and Gas Composition Abstraction Calculations for Different Drift Temperature Environments'' (BSC 2001c). A secondary objective is to predict evaporation effects on observed Yucca Mountain waters for subsequent cement interaction calculations (BSC 2001d). The Precipitates/Salts model is documented in an Analysis/Model Report (AMR), ''In-Drift Precipitates/Salts Analysis'' (BSC 2001b).
Preliminary Study of Jerome Model and Horace Model
Institute of Scientific and Technical Information of China (English)
周静; 蒋秀丽
2013-01-01
Translation always plays the crucial role in the cross-culture communication and the development of human being’s history of civilization. The author of this papertries to make an analysis and contrast of the two translation models: the Jerome model and the Horace model, pointing out that it is because of different circumstances that different translation models are used in the translation.
Energy Technology Data Exchange (ETDEWEB)
NONE
2005-09-15
The European Commission decided in 2001 an analysis program to reduce the atmospheric emissions. This report presents different limit scenari for France in 2020 (the reference scenari and the MTFR scenari, Maximum Technically Feasible Reduction), optimized scenari calculated by the RAINS model (Regional Air Pollution Information and Simulation), the costs of the scenari calculated with RAINS and the cost-benefit analysis of the strategy CAFE. From the study results, the benefits are higher than the costs, even with the most ambitious scenari. At an european level the emission reduction strategies have no effect on the employment but an impact on the Gross Domestic Product (decrease between 0,04 % and 0,12 % in function of the scenari). (A.L.B.)
A Calculation Model for Corrosion Cracking in RC Structures
Institute of Scientific and Technical Information of China (English)
Xu Gang; Wei Jun; Zhang Keqiang; Zhou Xiwu
2007-01-01
A novel calculation model is proposed aiming at the problem of concrete cover cracking induced by reinforcement corrosion. In this article, the relationship between the corrosion depth of the bar and the thickness of the rust layer is established. By deducing the radial displacement expression of concrete, the formula for corrosion depth and corrosion pressure before cracking is proposed. The crack depth of cover in accordance with the maximum corrosion pressure is deduced; furthermore, the corrosion depth and corrosion pressure at the cracking time are obtained. Finally, the theoretical model is validated by several experiments, and the calculated values agree well with the experiment results.
Recent Advances in Shell Evolution with Shell-Model Calculations
Utsuno, Yutaka; Tsunoda, Yusuke; Shimizu, Noritaka; Honma, Michio; Togashi, Tomoaki; Mizusaki, Takahiro
2014-01-01
Shell evolution in exotic nuclei is investigated with large-scale shell-model calculations. After presenting that the central and tensor forces produce distinctive ways of shell evolution, we show several recent results: (i) evolution of single-particle-like levels in antimony and cupper isotopes, (ii) shape coexistence in nickel isotopes understood in terms of configuration-dependent shell structure, and (iii) prediction of the evolution of the recently established $N=34$ magic number towards smaller proton numbers. In any case, large-scale shell-model calculations play indispensable roles in describing the interplay between single-particle character and correlation.
McKemmish, Laura K; Tennyson, Jonathan
2016-01-01
Accurate knowledge of the rovibronic near-infrared and visible spectra of vanadium monoxide (VO) is very important for studies of cool stellar and hot planetary atmospheres. Here, the required ab initio dipole moment and spin-orbit coupling curves for VO are produced. This data forms the basis of a new VO line list considering 13 different electronic states and containing over 277 million transitions. Open shell transition, metal diatomics are challenging species to model through ab initio quantum mechanics due to the large number of low-lying electronic states, significant spin-orbit coupling and strong static and dynamic electron correlation. Multi-reference configuration interaction methodologies using orbitals from a complete active space self-consistent-field (CASSCF) calculation are the standard technique for these systems. We use different state-specific or minimal-state CASSCF orbitals for each electronic state to maximise the calculation accuracy. The off-diagonal dipole moment controls the intensity...
Preliminary Study of the Gravimetric Local Geoid Model in Jordan:
Directory of Open Access Journals (Sweden)
A. Al-Zoubi
2007-06-01
Full Text Available Recently, there is an increased interest in studying and defining the Local and Regional Geoid Model worldwide, due to its importance in geodetic and geophysics applications. The use of the Global Positioning System (GPS is internationally growing, yet the lack of any Geoid Model for Jordan has limited the use of GPS for geodetic applications. Therefore, this work aims to present the preliminary results that we propose for The Gravimetric Jordanian Geoid Model (GeoJordan. The model is created using gravimetric data and the GravSoft program. The validation of this model is done by using GPS measurements and precise leveling at Amman area. However, a comparison between the Global Geopotential Models OSU91A and EGM96 showed great discrepancies through the presented results. Also, presenting the approach used to obtain the orthometric height from GPS ellipsoidal height measurements. Nevertheless, the error margin; obtained in this initial study of the GeoJordan after fitting the data with GPS/leveling measurement; is about (10cm, in tested area whereas the standard error of the created model is about (40cm.
Comparison of the performance of net radiation calculation models
DEFF Research Database (Denmark)
Kjærsgaard, Jeppe Hvelplund; Cuenca, R H; Martinez-Cob, A
2009-01-01
values of net radiation were calculated using three net outgoing long-wave radiation models and compared to measured values. Four meteorological datasets representing two climate regimes, a sub-humid, high-latitude environment and a semi-arid mid-latitude environment, were used to test the models...... meteorological input data is limited. Model predictions were found to have a higher bias and scatter when using summed calculated hourly time steps compared to using daily input data.......Daily values of net radiation are used in many applications of crop-growth modeling and agricultural water management. Measurements of net radiation are not part of the routine measurement program at many weather stations and are commonly estimated based on other meteorological parameters. Daily...
New calculations in Dirac gaugino models: operators, expansions, and effects
Carpenter, Linda M.; Goodman, Jessica
2015-07-01
In this work we calculate important one loop SUSY-breaking parameters in models with Dirac gauginos, which are implied by the existence of heavy messenger fields. We find that these SUSY-breaking effects are all related by a small number of parameters, thus the general theory is tightly predictive. In order to make the most accurate analyses of one loop effects, we introduce calculations using an expansion in SUSY breaking messenger mass, rather than relying on postulating the forms of effective operators. We use this expansion to calculate one loop contributions to gaugino masses, non-holomorphic SM adjoint masses, new A-like and B-like terms, and linear terms. We also test the Higgs potential in such models, and calculate one loop contributions to the Higgs mass in certain limits of R-symmetric models, finding a very large contribution in many regions of the [InlineMediaObject not available: see fulltext.], where Higgs fields couple to standard model adjoint fields.
Ab initio calculations and modelling of atomic cluster structure
DEFF Research Database (Denmark)
Solov'yov, Ilia; Lyalin, Andrey G.; Greiner, Walter
2004-01-01
framework for modelling the fusion process of noble gas clusters is presented. We report the striking correspondence of the peaks in the experimentally measured abundance mass spectra with the peaks in the size-dependence of the second derivative of the binding energy per atom calculated for the chain...... of the noble gas clusters up to 150 atoms....
The role of hand calculations in ground water flow modeling.
Haitjema, Henk
2006-01-01
Most ground water modeling courses focus on the use of computer models and pay little or no attention to traditional analytic solutions to ground water flow problems. This shift in education seems logical. Why waste time to learn about the method of images, or why study analytic solutions to one-dimensional or radial flow problems? Computer models solve much more realistic problems and offer sophisticated graphical output, such as contour plots of potentiometric levels and ground water path lines. However, analytic solutions to elementary ground water flow problems do have something to offer over computer models: insight. For instance, an analytic one-dimensional or radial flow solution, in terms of a mathematical expression, may reveal which parameters affect the success of calibrating a computer model and what to expect when changing parameter values. Similarly, solutions for periodic forcing of one-dimensional or radial flow systems have resulted in a simple decision criterion to assess whether or not transient flow modeling is needed. Basic water balance calculations may offer a useful check on computer-generated capture zones for wellhead protection or aquifer remediation. An easily calculated "characteristic leakage length" provides critical insight into surface water and ground water interactions and flow in multi-aquifer systems. The list goes on. Familiarity with elementary analytic solutions and the capability of performing some simple hand calculations can promote appropriate (computer) modeling techniques, avoids unnecessary complexity, improves reliability, and is likely to save time and money. Training in basic hand calculations should be an important part of the curriculum of ground water modeling courses.
Bakker, D.J.; Vries, W. de
1996-01-01
Methodologies are described for calculating critical loads of persistent organic pollutants (POPs) for soils and surface waters. The various aspects which are discussed, are: environmental quality criteria, calculation methods, input data and the various sources of uncertainty. The calculation
Microscopic Shell Model Calculations for the Fluorine Isotopes
Barrett, Bruce R.; Dikmen, Erdal; Maris, Pieter; Vary, James P.; Shirokov, Andrey M.
2015-10-01
Using a formalism based on the No Core Shell Model (NCSM), we have determined miscroscopically the core and single-particle energies and the effective two-body interactions that are the input to standard shell model (SSM) calculations. The basic idea is to perform a succession of a Okubo-Lee-Suzuki (OLS) transformation, a NCSM calculation, and a second OLS transformation to a further reduced space, such as the sd-shell, which allows the separation of the many-body matrix elements into an ``inert'' core part plus a few valence-nucleons calculation. In the present investigation we use this technique to calculate the properties of the nuclides in the Fluorine isotopic chain, using the JISP16 nucleon-nucleon interaction. The obtained SSM input, along with the results of the SSM calculations for the Fluorine isotopes, will be presented. This work supported in part by TUBITAK-BIDEB, the US DOE, the US NSF, NERSC, and the Russian Ministry of Education and Science.
Shell-model calculations of nuclei around mass 130
Teruya, E.; Yoshinaga, N.; Higashiyama, K.; Odahara, A.
2015-09-01
Shell-model calculations are performed for even-even, odd-mass, and doubly-odd nuclei of Sn, Sb, Te, I, Xe, Cs, and Ba isotopes around mass 130 using the single-particle space made up of valence nucleons occupying the 0 g7 /2 ,1 d5 /2 ,2 s1 /2 ,0 h11 /2 , and 1 d3 /2 orbitals. The calculated energies and electromagnetic transitions are compared with the experimental data. In addition, several typical isomers in this region are investigated.
Particle-rotor-model calculations in 125I
Indian Academy of Sciences (India)
Hariprakash Sharma; B Sethi; P Banerjee; Ranjana Goswami; R K Bhandari; Jahan Singh
2001-07-01
Recent experimental data on 125I has revealed several interesting structural features. These include the observation of a three quasiparticle band, prolate and oblate deformed bands, signature inversion in the yrast positive-parity band and identiﬁcation of the unfavoured ℎ11/2 band showing very large signature splitting. In the present work, particle-rotor-model calculations have been performed for the ℎ11/2 band, using an axially symmetric deformed Nilsson potential. The calculations reproduce the experimental results well and predict a moderate prolate quadrupole deformation of about 0.2 for the band.
Carbon footprint calculation model for the Mexican food equivalent system
Directory of Open Access Journals (Sweden)
Salvador Ruiz Cerrillo
2017-06-01
Full Text Available Introduction: the impact environment trough the anthropogenic action has been contributed to the fast production of greenhouse gases effect (GHG, a way to estimate the quantity of these substances is the carbon footprint (CF, nowadays it does not exist enough models for the calculation of food carbon footprint. Objective: the aim of this study was to design a calculation model for the measurement of the carbon footprint on the Mexican food equivalent system. Methods: it was about a retrospective study, a bibliographic review was made with original and review articles in different specialized researchers, there were included publications in English and Spanish, also published from 2000 to 2016. Results: a reference table was proposed for the food carbon footprint calculation on the Mexican food equivalent system trough the carbon intensity indicator, which is determined by the grams of emissions equivalents of carbon dioxide (CO2 in relation with the energetic contribution of each food equivalent. Conclusion: in a conclusion manner, estimating food carbon footprint is still a challenge, mean while the calculation models proposal is important to estimate the production of GHG trough a more sustainable food system.
Preliminary Results from Electric Arc Furnace Off-Gas Enthalpy Modeling
Energy Technology Data Exchange (ETDEWEB)
Nimbalkar, Sachin U [ORNL; Thekdi, Arvind [E3M Inc; Keiser, James R [ORNL; Storey, John Morse [ORNL
2015-01-01
This article describes electric arc furnace (EAF) off-gas enthalpy models developed at Oak Ridge National Laboratory (ORNL) to calculate overall heat availability (sensible and chemical enthalpy) and recoverable heat values (steam or power generation potential) for existing EAF operations and to test ORNL s new EAF waste heat recovery (WHR) concepts. ORNL s new EAF WHR concepts are: Regenerative Drop-out Box System and Fluidized Bed System. The two EAF off-gas enthalpy models described in this paper are: 1.Overall Waste Heat Recovery Model that calculates total heat availability in off-gases of existing EAF operations 2.Regenerative Drop-out Box System Model in which hot EAF off-gases alternately pass through one of two refractory heat sinks that store heat and then transfer it to another gaseous medium These models calculate the sensible and chemical enthalpy of EAF off-gases based on the off-gas chemical composition, temperature, and mass flow rate during tap to tap time, and variations in those parameters in terms of actual values over time. The models provide heat transfer analysis for the aforementioned concepts to confirm the overall system and major component sizing (preliminary) to assess the practicality of the systems. Real-time EAF off-gas composition (e.g., CO, CO2, H2, and H2O), volume flow, and temperature data from one EAF operation was used to test the validity and accuracy of the modeling work. The EAF off-gas data was used to calculate the sensible and chemical enthalpy of the EAF off-gases to generate steam and power. The article provides detailed results from the modeling work that are important to the success of ORNL s EAF WHR project. The EAF WHR project aims to develop and test new concepts and materials that allow cost-effective recovery of sensible and chemical heat from high-temperature gases discharged from EAFs.
Calculation Model and Simulation of Warship Damage Probability
Institute of Scientific and Technical Information of China (English)
TENG Zhao-xin; ZHANG Xu; YANG Shi-xing; ZHU Xiao-ping
2008-01-01
The combat efficiency of mine obstacle is the focus of the present research. Based on the main effects that mine obstacle has on the target warship damage probability such as: features of mines with maneuverability, the success rate of mine-laying, the hit probability, mine reliability and action probability, a calculation model of target warship mine-encounter probability is put forward under the condition that the route selection of target warships accords with even distribution and the course of target warships accords with normal distribution. And a damage probability model of mines with maneuverability to target warships is set up, a simulation way proved the model to be a high practicality.
Atmospheric neutrino flux calculation using the NRLMSISE00 atmospheric model
Honda, M; Kajita, T; Kasahara, K; Midorikawa, S
2015-01-01
In this paper, we extend the calculation of the atmospheric neutrino flux~\\cite{hkkm2004,hkkms2006,hkkm2011} to the sites in polar and tropical regions. In our earliest full 3D-calculation~\\cite{hkkm2004}, we used DPMJET-III~\\cite{dpm} for the hadronic interaction model above 5~GeV, and NUCRIN~\\cite{nucrin} below 5~GeV. We modified DPMJET-III as in Ref.~\\cite{hkkms2006} to reproduce the experimental muon spectra better, mainly using the data observed by BESS group~\\cite{BESSTeVpHemu}. In a recent work~\\cite{hkkm2011}, we introduced JAM interaction model for the low energy hadronic interactions. JAM is a nuclear interaction model developed with PHITS (Particle and Heavy-Ion Transport code System)~\\cite{phits}. In Ref.~\\cite{hkkm2011}, we could reproduce the observed muon flux at the low energies at balloon altitude with DPMJET-III above 32 GeV and JAM below that better than the combination of DPMJET-III above 5~GeV and NUCRIN below that. Besides the interaction model, we have also improved the calculation sche...
Synthetic vision and emotion calculation in intelligent virtual human modeling.
Zhao, Y; Kang, J; Wright, D K
2007-01-01
The virtual human technique can already provide vivid and believable human behaviour in more and more scenarios. Virtual humans are expected to replace real humans in hazardous situations to undertake tests and feed back valuable information. This paper will introduce a virtual human with a novel collision-based synthetic vision, short-term memory model and a capability to implement emotion calculation and decision making. The virtual character based on this model can 'see' what is in its field of view (FOV) and remember those objects. After that, a group of affective computing equations have been introduced. These equations have been implemented into a proposed emotion calculation process to enlighten emotion for virtual intelligent humans.
Black Hole Entropy Calculation in a Modified Thin Film Model
Indian Academy of Sciences (India)
Jingyi Zhang
2011-03-01
The thin film model is modified to calculate the black hole entropy. The difference from the original method is that the Parikh–Wilczek tunnelling framework is introduced and the self-gravitation of the emission particles is taken into account. In terms of our improvement, if the entropy is still proportional to the area, then the emission energy of the particles will satisfy = /360.
Study on calculation model of road lighting visibility
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
Visibility is an evaluation index for road lighting, which comprehensively influences the vision reliability of drivers and is a key factor for road lighting safety and energy saving. This paper introduces the concept of road lighting visibility and its influencing factors. It also explains the small target visibility calculation model for road lighting design, and describes the significance of establishing urban road lighting visibility standards from a point of view of visual function and visual comfort of drivers.
IBAR: Interacting boson model calculations for large system sizes
Casperson, R. J.
2012-04-01
Scaling the system size of the interacting boson model-1 (IBM-1) into the realm of hundreds of bosons has many interesting applications in the field of nuclear structure, most notably quantum phase transitions in nuclei. We introduce IBAR, a new software package for calculating the eigenvalues and eigenvectors of the IBM-1 Hamiltonian, for large numbers of bosons. Energies and wavefunctions of the nuclear states, as well as transition strengths between them, are calculated using these values. Numerical errors in the recursive calculation of reduced matrix elements of the d-boson creation operator are reduced by using an arbitrary precision mathematical library. This software has been tested for up to 1000 bosons using comparisons to analytic expressions. Comparisons have also been made to the code PHINT for smaller system sizes. Catalogue identifier: AELI_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AELI_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License version 3 No. of lines in distributed program, including test data, etc.: 28 734 No. of bytes in distributed program, including test data, etc.: 4 104 467 Distribution format: tar.gz Programming language: C++ Computer: Any computer system with a C++ compiler Operating system: Tested under Linux RAM: 150 MB for 1000 boson calculations with angular momenta of up to L=4 Classification: 17.18, 17.20 External routines: ARPACK (http://www.caam.rice.edu/software/ARPACK/) Nature of problem: Construction and diagonalization of large Hamiltonian matrices, using reduced matrix elements of the d-boson creation operator. Solution method: Reduced matrix elements of the d-boson creation operator have been stored in data files at machine precision, after being recursively calculated with higher than machine precision. The Hamiltonian matrix is calculated and diagonalized, and the requested transition strengths are calculated
Preliminary 2D numerical modeling of common granular problems
Wyser, Emmanuel; Jaboyedoff, Michel
2017-04-01
Granular studies received an increasing interest during the last decade. Many scientific investigations were successfully addressed to acknowledge the ubiquitous behavior of granular matter. We investigate liquid impacts onto granular beds, i.e. the influence of the packing and compaction-dilation transition. However, a physically-based model is still lacking to address complex microscopic features of granular bed response during liquid impacts such as compaction-dilation transition or granular bed uplifts (Wyser et al. in review). We present our preliminary 2D numerical modeling based on the Discrete Element Method (DEM) using nonlinear contact force law (the Hertz-Mindlin model) for disk shape particles. The algorithm is written in C programming language. Our 2D model provides an analytical tool to address granular problems such as i) granular collapses and ii) static granular assembliy problems. This provides a validation framework of our numerical approach by comparing our numerical results with previous laboratory experiments or numerical works. Inspired by the work of Warnett et al. (2014) and Staron & Hinch (2005), we studied i) the axisymetric collapse of granular columns. We addressed the scaling between the initial aspect ratio and the final runout distance. Our numerical results are in good aggreement with the previous studies of Warnett et al. (2014) and Staron & Hinch (2005). ii) Reproducing static problems for regular and randomly stacked particles provides a valid comparison to results of Egholm (2007). Vertical and horizontal stresses within the assembly are quite identical to stresses obtained by Egholm (2007), thus demonstating the consistency of our 2D numerical model. Our 2D numerical model is able to reproduce common granular case studies such as granular collapses or static problems. However, a sufficient small timestep should be used to ensure a good numerical consistency, resulting in higher computational time. The latter becomes critical
A review of Higgs mass calculations in supersymmetric models
DEFF Research Database (Denmark)
Draper, P.; Rzehak, H.
2016-01-01
related to the electroweak hierarchy problem. Perhaps the most extensively studied examples are supersymmetric models, which, while capable of producing a 125 GeV Higgs boson with SM-like properties, do so in non-generic parts of their parameter spaces. We review the computation of the Higgs mass...... in the Minimal Supersymmetric Standard Model, in particular the large radiative corrections required to lift mh to 125 GeV and their calculation via Feynman-diagrammatic and effective field theory techniques. This review is intended as an entry point for readers new to the field, and as a summary of the current...
Calculation of precise firing statistics in a neural network model
Cho, Myoung Won
2017-08-01
A precise prediction of neural firing dynamics is requisite to understand the function of and the learning process in a biological neural network which works depending on exact spike timings. Basically, the prediction of firing statistics is a delicate manybody problem because the firing probability of a neuron at a time is determined by the summation over all effects from past firing states. A neural network model with the Feynman path integral formulation is recently introduced. In this paper, we present several methods to calculate firing statistics in the model. We apply the methods to some cases and compare the theoretical predictions with simulation results.
Calculation of statistical entropic measures in a model of solids
Sanudo, Jaime
2012-01-01
In this work, a one-dimensional model of crystalline solids based on the Dirac comb limit of the Kronig-Penney model is considered. From the wave functions of the valence electrons, we calculate a statistical measure of complexity and the Fisher-Shannon information for the lower energy electronic bands appearing in the system. All these magnitudes present an extremal value for the case of solids having half-filled bands, a configuration where in general a high conductivity is attained in real solids, such as it happens with the monovalent metals.
Modeling Considerations for Ingestion Pathway Dose Calculations Using CAP88.
Stuenkel, David
2017-04-01
The CAP88-PC computer model was developed by the U.S. Environmental Protection Agency to demonstrate compliance under the National Emission Standards for Hazardous Air Pollutants (NESHAPS). The program combines atmospheric transport models with the terrestrial food chain models in the U.S. Nuclear Regulatory Commission Regulatory Guide 1.109 to compute the radionuclide concentrations in the air, on ground surfaces and plants, and the concentrations in food to estimate the dose to individuals living in the area around a facility emitting radionuclides into the atmosphere. CAP88 allows the user to select the size of the assessment area and the receptor locations used to calculate the radionuclide concentrations in non-leafy vegetables, leafy vegetables, milk, and meat consumed by the receptors. Depending on the food scenario selected and the type of calculation ("Population" or "Individual") chosen, the annual effective dose from ingestion can depend on both the size of the assessment area and the location of the receptors. Illustrative examples demonstrate the effect of the choice of these input parameters on the annual effective dose from ingestion. An understanding of the model used in CAP88 and the differences between "Population" and "Individual" run types will enable the CAP88 user to better model the ingestion dose.
Nuclear model calculations on cyclotron production of {sup 51}Cr
Energy Technology Data Exchange (ETDEWEB)
Kakavand, Tayeb [Imam Khomeini International Univ., Qazvin (Iran, Islamic Republic of). Dept. of Physics; Aboudzadeh, Mohammadreza [Nuclear Science and Technology Research Institute/AEOI, Karaj (Iran, Islamic Republic of). Agricultural, Medical and Industrial Research School; Farahani, Zahra; Eslami, Mohammad [Zanjan Univ. (Iran, Islamic Republic of). Dept. of Physics
2015-12-15
{sup 51}Cr (T{sub 1/2} = 27.7 d), which decays via electron capture (100 %) with 320 keV gamma emission (9.8 %), is a radionuclide with still a large application in biological studies. In this work, ALICE/ASH and TALYS nuclear model codes along with some adjustments are used to calculate the excitation functions for proton, deuteron, α-particle and neutron induced on various targets leading to the production of {sup 51}Cr radioisotope. The production yields of {sup 51}Cr from various reactions are determined using the excitation function calculations and stopping power data. The results are compared with corresponding experimental data and discussed from point of view of feasibility.
A simplified analytical random walk model for proton dose calculation
Yao, Weiguang; Merchant, Thomas E.; Farr, Jonathan B.
2016-10-01
We propose an analytical random walk model for proton dose calculation in a laterally homogeneous medium. A formula for the spatial fluence distribution of primary protons is derived. The variance of the spatial distribution is in the form of a distance-squared law of the angular distribution. To improve the accuracy of dose calculation in the Bragg peak region, the energy spectrum of the protons is used. The accuracy is validated against Monte Carlo simulation in water phantoms with either air gaps or a slab of bone inserted. The algorithm accurately reflects the dose dependence on the depth of the bone and can deal with small-field dosimetry. We further applied the algorithm to patients’ cases in the highly heterogeneous head and pelvis sites and used a gamma test to show the reasonable accuracy of the algorithm in these sites. Our algorithm is fast for clinical use.
EMPIRICAL MODEL FOR HYDROCYCLONES CORRECTED CUT SIZE CALCULATION
Directory of Open Access Journals (Sweden)
André Carlos Silva
2012-12-01
Full Text Available Hydrocyclones are devices worldwide used in mineral processing for desliming, classification, selective classification, thickening and pre-concentration. A hydrocyclone is composed by one cylindrical and one conical section joint together, without any moving parts and it is capable of perform granular material separation in pulp. The mineral particles separation mechanism acting in a hydrocyclone is complex and its mathematical modelling is usually empirical. The most used model for hydrocyclone corrected cut size is proposed by Plitt. Over the years many revisions and corrections to Plitt´s model were proposed. The present paper shows a modification in the Plitt´s model constant, obtained by exponential regression of simulated data for three different hydrocyclones geometry: Rietema, Bradley and Krebs. To validate the proposed model literature data obtained from phosphate ore using fifteen different hydrocyclones geometry are used. The proposed model shows a correlation equals to 88.2% between experimental and calculated corrected cut size, while the correlation obtained using Plitt´s model is 11.5%.
Mixed-Symmetry Shell-Model Calculations in Nuclear Physics
Gueorguiev, V G
2010-01-01
We consider a novel approach to the nuclear shell model. The one-dimensional harmonic oscillator in a box is used to introduce the concept of an oblique-basis shell-model theory. By implementing the Lanczos method for diagonalization of large matrices, and the Cholesky algorithm for solving generalized eigenvalue problems, the method is applied to nuclei. The mixed-symmetry basis combines traditional spherical shell-model states with SU(3) collective configurations. We test the validity of this mixed-symmetry scheme on 24Mg and 44Ti. Results for 24Mg, obtained using the Wilthental USD intersection in a space that spans less than 10% of the full-space, reproduce the binding energy within 2% as well as an accurate reproduction of the low-energy spectrum and the structure of the states - 90% overlap with the exact eigenstates. In contrast, for an m-scheme calculation, one needs about 60% of the full space to obtain compatible results. Calculations for 44Ti support the mixed-mode scheme although the pure SU(3) ca...
MODEL OF FEES CALCULATION FOR ACCESS TO TRACK INFRASTRUCTURE FACILITIES
Directory of Open Access Journals (Sweden)
M. I. Mishchenko
2014-12-01
Full Text Available Purpose. The purpose of the article is to develop a one- and two-element model of the fees calculation for the use of track infrastructure of Ukrainian railway transport. Methodology. On the basis of this one can consider that when planning the planned preventive track repair works and the amount of depreciation charges the guiding criterion is not the amount of progress it is the operating life of the track infrastructure facilities. The cost of PPTRW is determined on the basis of the following: the classification track repairs; typical technological processes for track repairs; technology based time standards for PPTRW; costs for the work of people, performing the PPTRW, their hourly wage rates according to the Order 98-Ts; the operating cost of machinery; regulated list; norms of expenditures and costs of materials and products (they have the largest share of the costs for repairs; railway rates; average distances for transportation of materials used during repair; standards of general production expenses and the administrative costs. Findings. The models offered in article allow executing the objective account of expenses in travelling facilities for the purpose of calculation of the proved size of indemnification and necessary size of profit, the sufficient enterprises for effective activity of a travelling infrastructure. Originality. The methodological bases of determination the fees (payments for the use of track infrastructure on one- and two-element base taking into account the experience of railways in the EC countries and the current transport legislation were grounded. Practical value. The article proposes the one- and two-element models of calculating the fees (payments for the TIF use, accounting the applicable requirements of European transport legislation, which provides the expense compensation and income formation, sufficient for economic incentives of the efficient operation of the TIE of Ukrainian railway transport.
Model test and CFD calculation of a cavitating bulb turbine
Energy Technology Data Exchange (ETDEWEB)
Necker, J; Aschenbrenner, T, E-mail: joerg.necker@voith.co [Voith Hydro Holding GmbH and Co. KG Alexanderstrasse 11, 89522 Heidenheim (Germany)
2010-08-15
The flow in a horizontal shaft bulb turbine is calculated as a two-phase flow with a commercial Computational Fluid Dynamics (CFD-)-code including cavitation model. The results are compared with experimental results achieved at a closed loop test rig for model turbines. On the model test rig, for a certain operating point (i.e. volume flow, net head, blade angle, guide vane opening) the pressure behind the turbine is lowered (i.e. the Thoma-coefficient {sigma} is lowered) and the efficiency of the turbine is recorded. The measured values can be depicted in a so-called {sigma}-break curve or {eta}- {sigma}-diagram. Usually, the efficiency is independent of the Thoma-coefficient up to a certain value. When lowering the Thoma-coefficient below this value the efficiency will drop rapidly. Visual observations of the different cavitation conditions complete the experiment. In analogy, several calculations are done for different Thoma-coefficients {sigma}and the corresponding hydraulic losses of the runner are evaluated quantitatively. For a low {sigma}-value showing in the experiment significant efficiency loss, the the change of volume flow in the experiment was simulated. Besides, the fraction of water vapour as an indication of the size of the cavitation cavity is analyzed qualitatively. The experimentally and the numerically obtained results are compared and show a good agreement. Especially the drop in efficiency can be calculated with satisfying accuracy. This drop in efficiency is of high practical importance since it is one criterion to determine the admissible cavitation in a bulb-turbine. The visual impression of the cavitation in the CFD-analysis is well in accordance with the observed cavitation bubbles recorded on sketches and/or photographs.
Finite element modelling of the tricuspid valve: A preliminary study.
Stevanella, Marco; Votta, Emiliano; Lemma, Massimo; Antona, Carlo; Redaelli, Alberto
2010-12-01
The incomplete efficacy of current surgical repair procedures of the tricuspid valve (TV) demands a deeper comprehension of the physiological TV biomechanics. To this purpose, computational models can provide quantitative insight into TV biomechanical response and allow analysing the role of each TV substructure. We present here a three-dimensional finite element model of the tricuspid valve that takes into account most of its peculiar features. Experimental measurements were performed on human and porcine valves to obtain a more detailed TV anatomical framework. To overcome the complete lack of information on leaflets mechanical properties, we performed a sensitivity analysis on the parameters of the adopted non-linear hyperelastic constitutive model, hypothesizing three different parameter sets for three significant collagen fibre distributions. Results showed that leaflets' motion and maximum principal stress distribution were almost insensitive to the different material parameters considered. Highest stresses (about 100kPa) were located near the annulus of the anterior and septal leaflets, while the posterior leaflet experienced lower stresses (about 55kPa); stresses at the commissures were nearly zero. Conversely, changes in constitutive parameters deeply affected leaflets' strains magnitude, but not their overall pattern. Strains computed assuming that TV leaflets tissue are reinforced by a sparse and loosely arranged network of collagen fibres fitted best experimental data, thus suggesting that this may be the actual microstructure of TV leaflets. In a long-term perspective, this preliminary study aims at providing a starting point for the development of a predictive tool to quantitatively evaluate TV diseases and surgical repair procedures.
Space resection model calculation based on Random Sample Consensus algorithm
Liu, Xinzhu; Kang, Zhizhong
2016-03-01
Resection has been one of the most important content in photogrammetry. It aims at the position and attitude information of camera at the shooting point. However in some cases, the observed values for calculating are with gross errors. This paper presents a robust algorithm that using RANSAC method with DLT model can effectually avoiding the difficulties to determine initial values when using co-linear equation. The results also show that our strategies can exclude crude handicap and lead to an accurate and efficient way to gain elements of exterior orientation.
Shell-model calculations for p-shell hypernuclei
Millener, D. J.
2012-01-01
The interpretation of hypernuclear gamma-ray data for p-shell hypernuclei in terms of shell-model calculations that include the coupling of Lambda- and Sigma-hypernuclear states is briefly reviewed. Next, Lambda 8Li, Lambda 8Be, and Lambda 9Li are considered, both to exhibit features of Lambda-Sigma coupling and as possible source of observed, but unassigned, hypernuclear gamma rays. Then, the feasibility of measuring the ground-state doublet spacing of Lambda 10Be, which, like Lambda 9Li, co...
Model and Calculation of Container Port Logistics Enterprises Efficiency Indexes
Directory of Open Access Journals (Sweden)
Xiao Hong
2013-04-01
Full Text Available The throughput of China’s container port is growing fast, but the earnings of inland port enterprises are not so good. Firstly ,the initial efficiency evaluation indexes of port logistics are reduced and screened by rough set model, and then logistics performance indexes weight are assigned by the rough totalitarian calculation method. As well, the rank of the indexes and the important indexes are picked up by combining with ABC management method. So the port logistics enterprises can monitor the key indexes to reduce cost and improve the efficiency of the logistics operations.
GMCALC: a calculator for the Georgi-Machacek model
Hartling, Katy; Logan, Heather E
2014-01-01
The Georgi-Machacek model adds scalar triplets to the Standard Model Higgs sector in such a way as to preserve custodial SU(2) symmetry in the scalar potential. This allows the triplets to have a non-negligible vacuum expectation value while satisfying constraints from the rho parameter. Depending on the parameters, the 125~GeV neutral Higgs particle can have couplings to WW and ZZ larger than in the Standard Model due to mixing with the triplets. The model also contains singly- and doubly-charged Higgs particles that couple to vector boson pairs at tree level (WZ and like-sign WW, respectively). GMCALC is a self-contained FORTRAN program that, given a set of input parameters, calculates the particle spectrum and tree-level couplings in the Georgi-Machacek model, checks theoretical and indirect constraints, and computes the branching ratios and total widths of the scalars. It also generates a param_card.dat file for MadGraph5 to be used with the corresponding FeynRules model implementation.
Mathematical Model and Programming in VBA Excel for Package Calculation
Directory of Open Access Journals (Sweden)
João Daniel Reis Lessa
2016-05-01
Full Text Available The industrial logistics is a fundamental pillar for the survival of companies in the actual increasingly competitive market. It is not exclusively about controlling the flow of external material between suppliers and the company, but for developing a detailed study of how to plan, control, handle and package those materials as well. Logistics activities must ensure the maximum efficiency in using corporate resources once they do not add value to the final product. The creation of a logistic plan, for each piece of the company’s production, has to adapt the demand parameters, seasonal or not, in the timeline. Thus, the definition of packaging (transportation and consumption must adjust in accordance with the demand, in order to allow the logistic planning to work, constantly, with order of economy batches. The packaging calculation for each part in every demand can become well complicated due to the large amount of parts in the production process. Automating the calculation process for choosing the right package for each piece is an effective method in logistics planning. This article will expose a simple and practical mathematical model for automating the packaging calculation and a logic program, created in Visual Basic language in the Excel software, used for creating graphic designs that show how the packages are being filled.
Calculating fermion masses in superstring derived standard-like models
Energy Technology Data Exchange (ETDEWEB)
Faraggi, A.E.
1996-04-01
One of the intriguing achievements of the superstring derived standard-like models in the free fermionic formulation is the possible explanation of the top quark mass hierarchy and the successful prediction of the top quark mass. An important property of the superstring derived standard-like models, which enhances their predictive power, is the existence of three and only three generations in the massless spectrum. Up to some motivated assumptions with regard to the light Higgs spectrum, it is then possible to calculate the fermion masses in terms of string tree level amplitudes and some VEVs that parameterize the string vacuum. I discuss the calculation of the heavy generation masses in the superstring derived standard-like models. The top quark Yukawa coupling is obtained from a cubic level mass term while the bottom quark and tau lepton mass terms are obtained from nonrenormalizable terms. The calculation of the heavy fermion Yukawa couplings is outlined in detail in a specific toy model. The dependence of the effective bottom quark and tau lepton Yukawa couplings on the flat directions at the string scale is examined. The gauge and Yukawa couplings are extrapolated from the string unification scale to low energies. Agreement with {alpha}{sub strong}, sin{sup 2} {theta}{sub W} and {alpha}{sub em} at M{sub Z} is imposed, which necessitates the existence of intermediate matter thresholds. The needed intermediate matter thresholds exist in the specific toy model. The effect of the intermediate matter thresholds on the extrapolated Yukawa couplings is studied. It is observed that the intermediate matter thresholds help to maintain the correct b/{tau} mass relation. It is found that for a large portion of the parameter space, the LEP precision data for {alpha}{sub strong}, sin{sup 2} {theta}{sub W} and {alpha}{sub em}, as well as the top quark mass and the b/{tau} mass relation can all simultaneously be consistent with the superstring derived standard-like models.
Effectively-truncated large-scale shell-model calculations and nuclei around 100Sn
Gargano, A.; Coraggio, L.; Itaco, N.
2017-09-01
This paper presents a short overview of a procedure we have recently introduced, dubbed the double-step truncation method, which is aimed to reduce the computational complexity of large-scale shell-model calculations. Within this procedure, one starts with a realistic shell-model Hamiltonian defined in a large model space, and then, by analyzing the effective single particle energies of this Hamiltonian as a function of the number of valence protons and/or neutrons, reduced model spaces are identified containing only the single-particle orbitals relevant to the description of the spectroscopic properties of a certain class of nuclei. As a final step, new effective shell-model Hamiltonians defined within the reduced model spaces are derived by way of a unitary transformation of the original large-scale Hamiltonian. A detailed account of this transformation is given and the merit of the double-step truncation method is illustrated by discussing few selected results for 96Mo, described as four protons and four neutrons outside 88Sr. Some new preliminary results for light odd-tin isotopes from A = 101 to 107 are also reported.
Recent Developments in No-Core Shell-Model Calculations
Energy Technology Data Exchange (ETDEWEB)
Navratil, P; Quaglioni, S; Stetcu, I; Barrett, B R
2009-03-20
We present an overview of recent results and developments of the no-core shell model (NCSM), an ab initio approach to the nuclear many-body problem for light nuclei. In this aproach, we start from realistic two-nucleon or two- plus three-nucleon interactions. Many-body calculations are performed using a finite harmonic-oscillator (HO) basis. To facilitate convergence for realistic inter-nucleon interactions that generate strong short-range correlations, we derive effective interactions by unitary transformations that are tailored to the HO basis truncation. For soft realistic interactions this might not be necessary. If that is the case, the NCSM calculations are variational. In either case, the ab initio NCSM preserves translational invariance of the nuclear many-body problem. In this review, we, in particular, highlight results obtained with the chiral two- plus three-nucleon interactions. We discuss efforts to extend the applicability of the NCSM to heavier nuclei and larger model spaces using importance-truncation schemes and/or use of effective interactions with a core. We outline an extension of the ab initio NCSM to the description of nuclear reactions by the resonating group method technique. A future direction of the approach, the ab initio NCSM with continuum, which will provide a complete description of nuclei as open systems with coupling of bound and continuum states is given in the concluding part of the review.
[Diffusion factor calculation for TIP4P model of water].
Zlenko, D V
2012-01-01
A molecular dynamics study has been undertaken for a model of liquid TIP4P water. Thermal dependencies of water density and radial distribution functions were calculated for model verification. Three methods have been used for calculation of diffusion factor thermal dependencies. Their sensitivity to molecular system size and length of used trajectory has been analyzed. It has been shown that Green-Kubo formula-based approach which associates diffusion factor with speed autocorrelation function integral is preferred in case of short MD simulations. The second approach based on Einstein equation which associates mean square displacement of molecule with time is preferred in case of long simulations. It has been also demonstrated that it is possible to modify the second approach to make it more stable and reliable. This modification is to use a slope of the graph of the mean square displacement on time as the estimation of the diffusion factor instead of the ratio of molecule mean square displacement and time.
Energy Technology Data Exchange (ETDEWEB)
Kneur, J.L
2006-06-15
This document is divided into 2 parts. The first part describes a particular re-summation technique of perturbative series that can give a non-perturbative results in some cases. We detail some applications in field theory and in condensed matter like the calculation of the effective temperature of Bose-Einstein condensates. The second part deals with the minimal supersymmetric standard model. We present an accurate calculation of the mass spectrum of supersymmetric particles, a calculation of the relic density of supersymmetric black matter, and the constraints that we can infer from models.
Multidirectional Networks of Government Transparency: A Preliminary Model
Directory of Open Access Journals (Sweden)
Ahmad Subhan
2016-11-01
Full Text Available This article reviews some literature in theoretical level regarding two concepts: governance network and government transparency, in order to search for theoretical linkages and to build an alternative framework that can support the implementation of public disclosure. Transparency agenda has been implemented in various forms at international, national, and local level. Transparency application was also followed by Indonesia with the implementation of Public Information Disclosure Law since 2008. This enthusiasm is quite reasonable because transparency is believed to be one of the human rights principles; as well as a key to better governance, that can help democracy consolidation, prevent corruption, strengthen the legitimacy and improve efficiency. In order to maximize transparency, the government can use a network approach because of some changes at this time, such as democratization, decentralization, and liberalization has placed the government in a position where there is not one actor who manages the state power without stakeholder’s participation. In this context, the government needs to build synergies with other institutions in a reciprocal relationship with all stakeholders. Therefore, adopting the theory of government networks can be one of the strategies to strengthen government transparency. The findings of this article indicate that the government transparency application needs to develop networks in all directions: intragovernmental, intergovernmental and collaborative networks. These three types of network in contrast with the popular belief that government transparency is interpreted only as a procedural activity to outside parties. A preliminary model in this article gives an overview about the arena of government transparency with multi-directional networks more comprehensively.
Nonlinear damping calculation in cylindrical gear dynamic modeling
Guilbault, Raynald; Lalonde, Sébastien; Thomas, Marc
2012-04-01
The nonlinear dynamic problem posed by cylindrical gear systems has been extensively covered in the literature. Nonetheless, a significant proportion of the mechanisms involved in damping generation remains to be investigated and described. The main objective of this study is to contribute to this task. Overall, damping is assumed to consist of three sources: surrounding element contribution, hysteresis of the teeth, and oil squeeze damping. The first two contributions are considered to be commensurate with the supported load; for its part however, squeeze damping is formulated using expressions developed from the Reynolds equation. A lubricated impact analysis between the teeth is introduced in this study for the minimum film thickness calculation during contact losses. The dynamic transmission error (DTE) obtained from the final model showed close agreement with experimental measurements available in the literature. The nonlinear damping ratio calculated at different mesh frequencies and torque amplitudes presented average values between 5.3 percent and 8 percent, which is comparable to the constant 8 percent ratio used in published numerical simulations of an equivalent gear pair. A close analysis of the oil squeeze damping evidenced the inverse relationship between this damping effect and the applied load.
Unquenched quark-model calculation of X(3872) electromagnetic decays
Energy Technology Data Exchange (ETDEWEB)
Cardoso, Marco [Universidade de Lisboa, Centro de Fisica Teorica de Particulas, Instituto Superior Tecnico, Lisbon (Portugal); Rupp, George [Universidade de Lisboa, Centro de Fisica das Interaccoes Fundamentais, Instituto Superior Tecnico, Lisbon (Portugal); Beveren, Eef van [Universidade de Coimbra, Departamento de Fisica, Centro de Fisica Computacional, Coimbra (Portugal)
2015-01-01
A recent quark-model description of X(3872) as an unquenched 2{sup 3}P{sub 1} c anti c state is generalised by now including all relevant meson.meson configurations, in order to calculate the widths of the experimentally observed electromagnetic decays X(3872) → γJ/ψ and X(3872) → γψ(2S). Interestingly, the inclusion of additional two-meson channels, most importantly D{sup ±}D{sup *-+}, leads to a sizeable increase of the c anti c probability in the total wave function, although the D{sup 0} anti D{sup *0} component remains the dominant one. As for the electromagnetic decays, unquenching strongly reduces the γψ(2S) decay rate; yet it even more sharply enhances the γJ/ψ rate, resulting in a decay ratio compatible with one experimental observation but in slight disagreement with two others. Nevertheless, the results show a dramatic improvement as compared to a quenched calculation with the same confinement force and parameters. Concretely, we obtain Γ (X(3872) → γψ(2S)) = 28.9 keV and Γ (X(3872) → γJ/ψ) = 24.7 keV, with branching ratio R{sub γψ} = 1.17. (orig.)
Relativistic effects in model calculations of double parton distribution function
Rinaldi, Matteo
2016-01-01
In this paper we consider double parton distribution functions (dPDFs) which are the main non perturbative ingredients appearing in the double parton scattering cross section formula in hadronic collisions. By using recent calculation of dPDFs by means of constituent quark models within the so called Light-Front approach, we investigate the role of relativistic effects on dPDFs. We find, in particular, that the so called Melosh operators, which allow to properly convert the LF spin into the canonical one and incorporate a proper treatment of boosts, produce sizeable effects on dPDFs. We discuss specific partonic correlations induced by these operators in transverse plane which are relevant to the proton structure and study under which conditions these results are stable against variations in the choice of the proton wave function.
Observations, Thermochemical Calculations, and Modeling of Exoplanetary Atmospheres
Blecic, Jasmina
2016-01-01
This dissertation as a whole aims to provide means to better understand hot-Jupiter planets through observing, performing thermochemical calculations, and modeling their atmospheres. We used Spitzer multi-wavelength secondary-eclipse observations and targets with high signal-to-noise ratios, as their deep eclipses allow us to detect signatures of spectral features and assess planetary atmospheric structure and composition with greater certainty. Chapter 1 gives a short introduction. Chapter 2 presents the Spitzer secondary-eclipse analysis and atmospheric characterization of WASP-14b. WASP-14b is a highly irradiated, transiting hot Jupiter. By applying a Bayesian approach in the atmospheric analysis, we found an absence of thermal inversion contrary to theoretical predictions. Chapter 3 describes the infrared observations of WASP-43b Spitzer secondary eclipses, data analysis, and atmospheric characterization. WASP-43b is one of the closest-orbiting hot Jupiters, orbiting one of the coolest stars with a hot Ju...
Quantum plasmonics: from jellium models to ab initio calculations
Directory of Open Access Journals (Sweden)
Varas Alejandro
2016-08-01
Full Text Available Light-matter interaction in plasmonic nanostructures is often treated within the realm of classical optics. However, recent experimental findings show the need to go beyond the classical models to explain and predict the plasmonic response at the nanoscale. A prototypical system is a nanoparticle dimer, extensively studied using both classical and quantum prescriptions. However, only very recently, fully ab initio time-dependent density functional theory (TDDFT calculations of the optical response of these dimers have been carried out. Here, we review the recent work on the impact of the atomic structure on the optical properties of such systems. We show that TDDFT can be an invaluable tool to simulate the time evolution of plasmonic modes, providing fundamental understanding into the underlying microscopical mechanisms.
The EOSTA model for opacities and EOS calculations
Barshalom, Avraham; Oreg, Joseph
2007-11-01
The EOSTA model developed recently combines the STA and INFERNO models to calculate opacities and EOS on the same footing. The quantum treatment of the plasma continuum and the inclusion of the resulted shape resonances yield a smooth behavior of the EOS and opacity global quantities vs density and temperature. We will describe the combined model and focus on its latest improvements. In particular we have extended the use of the special representation of the relativistic virial theorem to obtain an exact differential equation for the free energy. This equation, combined with a boundary condition at the zero pressure point, serves to advance the LDA EOS results significantly. The method focuses on applicability to high temperature and high density plasmas, warm dens matter etc. but applies at low temperatures as well treating fluids and even solids. Excellent agreement is obtained with experiments covering a wide range of density and temperature. The code is now used to create EOS and opacity databases for the use of hydro-dynamical simulations.
Selection of models to calculate the LLW source term
Energy Technology Data Exchange (ETDEWEB)
Sullivan, T.M. (Brookhaven National Lab., Upton, NY (United States))
1991-10-01
Performance assessment of a LLW disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). In turn, many of these physical processes are influenced by the design of the disposal facility (e.g., infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This document provides a brief overview of disposal practices and reviews existing source term models as background for selecting appropriate models for estimating the source term. The selection rationale and the mathematical details of the models are presented. Finally, guidance is presented for combining the inventory data with appropriate mechanisms describing release from the disposal facility. 44 refs., 6 figs., 1 tab.
Energy Technology Data Exchange (ETDEWEB)
Mein, S [Duke University Medical Physics Graduate Program (United States); Gunasingha, R [Department of Radiation Safety, Duke University Medical Center (United States); Nolan, M [Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University (United States); Oldham, M; Adamson, J [Department of Radiation Oncology, Duke University Medical Center (United States)
2016-06-15
Purpose: X-PACT is an experimental cancer therapy where kV x-rays are used to photo-activate anti-cancer therapeutics through phosphor intermediaries (phosphors that absorb x-rays and re-radiate as UV light). Clinical trials in pet dogs are currently underway (NC State College of Veterinary Medicine) and an essential component is the ability to model the kV dose in these dogs. Here we report the commissioning and characterization of a Monte Carlo (MC) treatment planning simulation tool to calculate X-PACT radiation doses in canine trials. Methods: FLUKA multi-particle MC simulation package was used to simulate a standard X-PACT radiation treatment beam of 80kVp with the Varian OBI x-ray source geometry. The beam quality was verified by comparing measured and simulated attenuation of the beam by various thicknesses of aluminum (2–4.6 mm) under narrow beam conditions (HVL). The beam parameters at commissioning were then corroborated using MC, characterized and verified with empirically collected commissioning data, including: percent depth dose curves (PDD), back-scatter factors (BSF), collimator scatter factor(s), and heel effect, etc. All simulations were conducted for N=30M histories at M=100 iterations. Results: HVL and PDD simulation data agreed with an average percent error of 2.42%±0.33 and 6.03%±1.58, respectively. The mean square error (MSE) values for HVL and PDD (0.07% and 0.50%) were low, as expected; however, longer simulations are required to validate convergence to the expected values. Qualitatively, pre- and post-filtration source spectra matched well with 80kVp references generated via SPEKTR software. Further validation of commissioning data simulation is underway in preparation for first-time 3D dose calculations with canine CBCT data. Conclusion: We have prepared a Monte Carlo simulation capable of accurate dose calculation for use with ongoing X-PACT canine clinical trials. Preliminary results show good agreement with measured data and hold
[Model calculation to explain the BSE-incidence in Germany].
Oberthür, Radulf C
2004-01-01
The future development of BSE-incidence in Germany is investigated using a simple epidemiological model calculation. Starting point is the development of the incidence of confirmed suspect BSE-cases in Great Britain since 1988, the hitherto known mechanisms of transmission and the measures taken to decrease the risk of transmission as well as the development of the BSE-incidence in Germany obtained from active post mortem laboratory testing of all cattle older then 24 months. The risk of transmission is characterized by the reproduction ratio of the disease. There is a shift in time between the risk of BSE transmission and the BSE incidence caused by the incubation time of more than 4 years. The observed decrease of the incidence in Germany from 2001 to 2003 is not a consequence of the measures taken at the end of 2000 to contain the disease. It can rather be explained by an import of BSE contaminated products from countries with a high BSE incidence in the years 1995/96 being used in calf feeding in Germany. From the future course of the BSE-incidence in Germany after 2003 a quantification of the recycling rate of BSE-infected material within Germany before the end of 2000 will be possible by use of the proposed model if the active surveillance is continued.
Comparative analysis of calculation models of railway subgrade
Directory of Open Access Journals (Sweden)
I.O. Sviatko
2013-08-01
Full Text Available Purpose. In transport engineering structures design, the primary task is to determine the parameters of foundation soil and nuances of its work under loads. It is very important to determine the parameters of shear resistance and the parameters, determining the development of deep deformations in foundation soils, while calculating the soil subgrade - upper track structure interaction. Search for generalized numerical modeling methods of embankment foundation soil work that include not only the analysis of the foundation stress state but also of its deformed one. Methodology. The analysis of existing modern and classical methods of numerical simulation of soil samples under static load was made. Findings. According to traditional methods of analysis of ground masses work, limitation and the qualitative estimation of subgrade deformations is possible only indirectly, through the estimation of stress and comparison of received values with the boundary ones. Originality. A new computational model was proposed in which it will be applied not only classical approach analysis of the soil subgrade stress state, but deformed state will be also taken into account. Practical value. The analysis showed that for accurate analysis of ground masses work it is necessary to develop a generalized methodology for analyzing of the rolling stock - railway subgrade interaction, which will use not only the classical approach of analyzing the soil subgrade stress state, but also take into account its deformed one.
Relative Binding Free Energy Calculations Applied to Protein Homology Models.
Cappel, Daniel; Hall, Michelle Lynn; Lenselink, Eelke B; Beuming, Thijs; Qi, Jun; Bradner, James; Sherman, Woody
2016-12-27
A significant challenge and potential high-value application of computer-aided drug design is the accurate prediction of protein-ligand binding affinities. Free energy perturbation (FEP) using molecular dynamics (MD) sampling is among the most suitable approaches to achieve accurate binding free energy predictions, due to the rigorous statistical framework of the methodology, correct representation of the energetics, and thorough treatment of the important degrees of freedom in the system (including explicit waters). Recent advances in sampling methods and force fields coupled with vast increases in computational resources have made FEP a viable technology to drive hit-to-lead and lead optimization, allowing for more efficient cycles of medicinal chemistry and the possibility to explore much larger chemical spaces. However, previous FEP applications have focused on systems with high-resolution crystal structures of the target as starting points-something that is not always available in drug discovery projects. As such, the ability to apply FEP on homology models would greatly expand the domain of applicability of FEP in drug discovery. In this work we apply a particular implementation of FEP, called FEP+, on congeneric ligand series binding to four diverse targets: a kinase (Tyk2), an epigenetic bromodomain (BRD4), a transmembrane GPCR (A2A), and a protein-protein interaction interface (BCL-2 family protein MCL-1). We apply FEP+ using both crystal structures and homology models as starting points and find that the performance using homology models is generally on a par with the results when using crystal structures. The robustness of the calculations to structural variations in the input models can likely be attributed to the conformational sampling in the molecular dynamics simulations, which allows the modeled receptor to adapt to the "real" conformation for each ligand in the series. This work exemplifies the advantages of using all-atom simulation methods with
Accurate Holdup Calculations with Predictive Modeling & Data Integration
Energy Technology Data Exchange (ETDEWEB)
Azmy, Yousry [North Carolina State Univ., Raleigh, NC (United States). Dept. of Nuclear Engineering; Cacuci, Dan [Univ. of South Carolina, Columbia, SC (United States). Dept. of Mechanical Engineering
2017-04-03
In facilities that process special nuclear material (SNM) it is important to account accurately for the fissile material that enters and leaves the plant. Although there are many stages and processes through which materials must be traced and measured, the focus of this project is material that is “held-up” in equipment, pipes, and ducts during normal operation and that can accumulate over time into significant quantities. Accurately estimating the holdup is essential for proper SNM accounting (vis-à-vis nuclear non-proliferation), criticality and radiation safety, waste management, and efficient plant operation. Usually it is not possible to directly measure the holdup quantity and location, so these must be inferred from measured radiation fields, primarily gamma and less frequently neutrons. Current methods to quantify holdup, i.e. Generalized Geometry Holdup (GGH), primarily rely on simple source configurations and crude radiation transport models aided by ad hoc correction factors. This project seeks an alternate method of performing measurement-based holdup calculations using a predictive model that employs state-of-the-art radiation transport codes capable of accurately simulating such situations. Inverse and data assimilation methods use the forward transport model to search for a source configuration that best matches the measured data and simultaneously provide an estimate of the level of confidence in the correctness of such configuration. In this work the holdup problem is re-interpreted as an inverse problem that is under-determined, hence may permit multiple solutions. A probabilistic approach is applied to solving the resulting inverse problem. This approach rates possible solutions according to their plausibility given the measurements and initial information. This is accomplished through the use of Bayes’ Theorem that resolves the issue of multiple solutions by giving an estimate of the probability of observing each possible solution. To use
Borque-Fernando, Á; Esteban-Escaño, L M; Rubio-Briones, J; Lou-Mercadé, A C; García-Ruiz, R; Tejero-Sánchez, A; Muñoz-Rivero, M V; Cabañuz-Plo, T; Alfaro-Torres, J; Marquina-Ibáñez, I M; Hakim-Alonso, S; Mejía-Urbáez, E; Gil-Fabra, J; Gil-Martínez, P; Ávarez-Alegret, R; Sanz, G; Gil-Sanz, M J
2016-04-01
To prevent the overdiagnosis and overtreatment of prostate cancer (PC), therapeutic strategies have been established such as active surveillance and focal therapy, as well as methods for clarifying the diagnosis of high-grade prostate cancer (HGPC) (defined as a Gleason score ≥7), such as multiparametric magnetic resonance imaging and new markers such as the 4Kscore test (4KsT). By means of a pilot study, we aim to test the ability of the 4KsT to identify HGPC in prostate biopsies (Bx) and compare the test with other multivariate prognostic models such as the Prostate Cancer Prevention Trial Risk Calculator 2.0 (PCPTRC 2.0) and the European Research Screening Prostate Cancer Risk Calculator 4 (ERSPC-RC 4). Fifty-one patients underwent a prostate Bx according to standard clinical practice, with a minimum of 10 cores. The diagnosis of HGPC was agreed upon by 4 uropathologists. We compared the predictions from the various models by using the Mann-Whitney U test, area under the ROC curve (AUC) (DeLong test), probability density function (PDF), box plots and clinical utility curves. Forty-three percent of the patients had PC, and 23.5% had HGPC. The medians of probability for the 4KsT, PCPTRC 2.0 and ERSPC-RC 4 were significantly different between the patients with HGPC and those without HGPC (p≤.022) and were more differentiated in the case of 4KsT (51.5% for HGPC [25-75 percentile: 25-80.5%] vs. 16% [P 25-75: 8-26.5%] for non-HGPC; p=.002). All models presented AUCs above 0.7, with no significant differences between any of them and 4KsT (p≥.20). The PDF and box plots showed good discriminative ability, especially in the ERSPC-RC 4 and 4KsT models. The utility curves showed how a cutoff of 9% for 4KsT identified all cases of HGPC and provided a 22% savings in biopsies, which is similar to what occurs with the ERSPC-RC 4 models and a cutoff of 3%. The assessed predictive models offer good discriminative ability for HGPCs in Bx. The 4KsT is a good classification
Groundwater flow modelling under ice sheet conditions. Scoping calculations
Energy Technology Data Exchange (ETDEWEB)
Jaquet, O.; Namar, R. (In2Earth Modelling Ltd (Switzerland)); Jansson, P. (Dept. of Physical Geography and Quaternary Geology, Stockholm Univ., Stockholm (Sweden))
2010-10-15
The potential impact of long-term climate changes has to be evaluated with respect to repository performance and safety. In particular, glacial periods of advancing and retreating ice sheet and prolonged permafrost conditions are likely to occur over the repository site. The growth and decay of ice sheets and the associated distribution of permafrost will affect the groundwater flow field and its composition. As large changes may take place, the understanding of groundwater flow patterns in connection to glaciations is an important issue for the geological disposal at long term. During a glacial period, the performance of the repository could be weakened by some of the following conditions and associated processes: - Maximum pressure at repository depth (canister failure). - Maximum permafrost depth (canister failure, buffer function). - Concentration of groundwater oxygen (canister corrosion). - Groundwater salinity (buffer stability). - Glacially induced earthquakes (canister failure). Therefore, the GAP project aims at understanding key hydrogeological issues as well as answering specific questions: - Regional groundwater flow system under ice sheet conditions. - Flow and infiltration conditions at the ice sheet bed. - Penetration depth of glacial meltwater into the bedrock. - Water chemical composition at repository depth in presence of glacial effects. - Role of the taliks, located in front of the ice sheet, likely to act as potential discharge zones of deep groundwater flow. - Influence of permafrost distribution on the groundwater flow system in relation to build-up and thawing periods. - Consequences of glacially induced earthquakes on the groundwater flow system. Some answers will be provided by the field data and investigations; the integration of the information and the dynamic characterisation of the key processes will be obtained using numerical modelling. Since most of the data are not yet available, some scoping calculations are performed using the
Preliminary modeling of BNCT beam tube on IRT in Sofia.
Belousov, S; Ilieva, K
2009-07-01
The technical design of the research reactor IRT in Sofia is in progress. It includes an arrangement for a BNCT facility for tumor treatment. Modeling of geometry and material composition of filter/collimator for the BNCT beam tube on IRT has been carried out following the beam tube configuration of the Massachusetts Institute of Technology Reactor [Harling et al., 2002. The fission converter-based epithermal neutron irradiation facility at the Massachusetts Institute of Technology Reactor. Nucl. Sci. Eng. 140, 223-240.] and taking into account an ability to include the tube into the IRT reactor geometry. The results of neutron and gamma transport calculations performed for the model have shown that the facility will be able to supply an epithermal neutron flux of about 5 x 10(9) n cm(-2)s(-1), with low contamination from fast neutrons and gamma rays that would be among the best facilities currently available. An optimiziation study has been performed for the beam collimator, following similar studies for the TAPIRO research reactor in Italy. [Nava et al., 2005. Monte Carlo optimization of a BNCT facility for treating brain gliomas at the TAPIRO reactor. Radiat. Prot. Dosim. 116 (1-4), 475-481.].
Full waveform modelling and misfit calculation using the VERCE platform
Garth, Thomas; Spinuso, Alessandro; Casarotti, Emanuele; Magnoni, Federica; Krischner, Lion; Igel, Heiner; Schwichtenberg, Horst; Frank, Anton; Vilotte, Jean-Pierre; Rietbrock, Andreas
2016-04-01
simulated and recorded waveforms, enabling seismologists to specify and steer their misfit analyses using existing python tools and libraries such as Pyflex and the dispel4py data-intensive processing library. All these processes, including simulation, data access, pre-processing and misfit calculation, are presented to the users of the gateway as dedicated and interactive workspaces. The VERCE platform can also be used to produce animations of seismic wave propagation through the velocity model, and synthetic shake maps. We demonstrate the functionality of the VERCE platform with two case studies, using the pre-loaded velocity model and mesh for Chile and Northern Italy. It is envisioned that this tool will allow a much greater range of seismologists to access these full waveform inversion tools, and aid full waveform tomographic and source inversion, synthetic shake map production and other full waveform applications, in a wide range of tectonic settings.
Coarse grained model for calculating the ion mobility of hydrocarbons
Kuroboshi, Y.; Takemura, K.
2016-12-01
Hydrocarbons are widely used as insulating compounds. However, their fundamental characteristics in conduction phenomena are not completely understood. A great deal of effort is required to determine reasonable ionic behavior from experiments because of their complicated procedures and tight controls of the temperature and the purity of the liquids. In order to understand the conduction phenomena, we have theoretically calculated the ion mobilities of hydrocarbons and investigated their characteristics using the coarse grained model in molecular dynamics simulations. We assumed a molecule of hydrocarbons to be a bead and simulated its dependence on the viscosity, electric field, and temperature. Furthermore, we verified the suitability of the conformation, scale size, and long-range interactions for the ion mobility. The results of the simulations show that the ion mobility values agree reasonably well with the values from Walden's rule and depend on the viscosity but not on the electric field. The ion mobility and self-diffusion coefficient exponentially increase with increasing temperature, while the activation energy decreases with increasing molecular size. These values and characteristics of the ion mobility are in reasonable agreement with experimental results. In the future, we can understand not only the ion mobilies of hydrocarbons in conduction, but also we can predict general phenomena in electrochemistry with molecular dynamics simulations.
MCNPX Cosmic Ray Shielding Calculations with the NORMAN Phantom Model
James, Michael R.; Durkee, Joe W.; McKinney, Gregg; Singleterry Robert
2008-01-01
The United States is planning manned lunar and interplanetary missions in the coming years. Shielding from cosmic rays is a critical aspect of manned spaceflight. These ventures will present exposure issues involving the interplanetary Galactic Cosmic Ray (GCR) environment. GCRs are comprised primarily of protons (approx.84.5%) and alpha-particles (approx.14.7%), while the remainder is comprised of massive, highly energetic nuclei. The National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) has commissioned a joint study with Los Alamos National Laboratory (LANL) to investigate the interaction of the GCR environment with humans using high-fidelity, state-of-the-art computer simulations. The simulations involve shielding and dose calculations in order to assess radiation effects in various organs. The simulations are being conducted using high-resolution voxel-phantom models and the MCNPX[1] Monte Carlo radiation-transport code. Recent advances in MCNPX physics packages now enable simulated transport over 2200 types of ions of widely varying energies in large, intricate geometries. We report here initial results obtained using a GCR spectrum and a NORMAN[3] phantom.
Stochastic index model for intermittent regimes: from preliminary analysis to regionalisation
Directory of Open Access Journals (Sweden)
M. Rianna
2011-04-01
Full Text Available In small and medium-sized basins or in rivers characterized by intermittent discharges, with low or negligible/null observed values for long periods of the year, the correct representation of the discharge regime is important for issues related to water management and to define the amount and quality of water available for irrigation, domestic and recreational uses. In these cases, only one index as a statistical metric is often not enough; it is thus necessary to introduce Flow Duration Curves (FDC.
The aim of this study is therefore to combine a stochastic index flow model capable of reproducing the FDC record period of a river, regardless of the persistence and seasonality of the series, with the theory of total probability in order to calculate how often a river is dry.
The paper draws from preliminary analyses, including a study to estimate the correlation between discharge indicators Q_{95}, Q_{50} and Q_{1} (discharges exceeding 95%, 50% or 1% of the time, respectively and some fundamental characteristics of the basin, as well as to identify homogeneous regions in the target area through the study of several geo-morphological features and climatic conditions. The stochastic model was then applied in one of the homogeneous regions that includes intermittent rivers.
Finally, the model was regionalized by means of regression analysis in order to calculate the FDC for ungauged basins; the reliability of this method was tested using jack-knife validation.
Entropy in spin foam models: the statistical calculation
Energy Technology Data Exchange (ETDEWEB)
Garcia-Islas, J Manuel, E-mail: jmgislas@leibniz.iimas.unam.m [Instituto de Investigaciones en Matematicas Aplicadas y en Sistemas, Universidad Nacional Autonoma de Mexico, UNAM, A. Postal 20-726, 01000, Mexico DF (Mexico)
2010-07-21
Recently an idea for computing the entropy of black holes in the spin foam formalism has been introduced. Particularly complete calculations for the three-dimensional Euclidean BTZ black hole were performed. The whole calculation is based on observables living at the horizon of the black hole universe. Departing from this idea of observables living at the horizon, we now go further and compute the entropy of the BTZ black hole in the spirit of statistical mechanics. We compare both calculations and show that they are very interrelated and equally valid. This latter behaviour is certainly due to the importance of the observables.
Waggoner, E. G.; Phillips, P. S.; Viken, J. K.; Davis, W. H.
1985-01-01
NASA Langley and NASA Ames-Dryden have defined a variable-sweep transition-flight experiment utilizing the F-14 aircraft to enhance understanding of the interaction of crossflow and Tollmien-Schlichting instabilities on a laminar-boundary-layer transition. The F-14 wing outer panel will be modified to generate favorable pressure gradients on the upper wing surface over a wide range of flight conditions. Extensive computations have been performed using two-dimensional and three-dimensional transonic analysis codes. Flight-test and computational data are compared and shown to validate the applicability of the three-dimensional codes (WBPPW and TAWFIVE). In addition, results from two preliminary glove designs derived from two different approaches to the design problem are presented. Advantages and disadvantages of each approach are identified, and it is concluded that coupling an analysis code with an automated design procedure yields a powerful code with distinct advantages over a 'cut-and-dry' approach.
Modelling of extreme gusts for design calculations (NewGust)
Energy Technology Data Exchange (ETDEWEB)
Bierbooms, W.; Po-Wen Cheng [Delft Univ. of Technology, Inst. for Wind Energy, Delft (Netherlands); Larsen, G. [Risoe National Lab., Roskilde (Denmark); Juul Pedersen, B. [Vestas Wind Systems A/S, Lem (Denmark); Hansen, K. [Tecnical Univ. of Denmark (Denmark)
1999-03-01
The main objective of the NewGust project is to come to a realistic and verified description of extreme gusts based on the stochastic properties of wind. In this paper the first results of the project are presented. Theoretical considerations indicate that the shape of extreme gusts is very sharp. Based on simulated wind time series, mean gust shapes (for several amplitudes and mean wind speeds) are determined and compared with the theoretical curves. The resemblance turned out to be very good. Furthermore, the influence of the sampling rate and the dynamics of a cup anemometer on the empirical mean gust shape are examined. The promising results are confirmed by a (preliminary) verification based on measured wind time series, available from the database on wind characteristics. The mean shape of gusts, of certain amplitude, together with their probability of occurrence can be used to obtain the distribution of the extreme response of wind turbines to gust loading. (au)
Preliminary study of the Gravimetric Local Geoid Model in Jordan: case study (GeoJordan Model
Directory of Open Access Journals (Sweden)
A. Al-Zoubi
2007-06-01
Full Text Available Recently, there has been an increased interest in studying and defining the Local and Regional Geoid Model worldwide, due to its importance in geodetic and geophysics applications.The use of the Global Positioning System (GPS is internationally growing, yet the lack of a Geoid Model for Jordan has limited the use of GPS for the geodetic applications in the country. This work aims to present the preliminary results that we propose for «The Gravimetric Jordanian Geoid Model (GeoJordan». The model is created using gravimetric data and the GRAVSOFT program. The model is validated using GPS and precise level measurements in the Amman area. Moreover, we present a comparison using the Global Geopotential Model OSU91A and the EGM96 Model and the results showed great discrepancies. We also present the approach used to obtain the orthometric height from GPS ellipsoidal height measurements. We found that the error margin obtained in this work of the GeoJordan after fitting the data with GPS/leveling measurements is about (10 cm in the tested area whereas the standard error of the created model is about (40 cm.
Molecular modeling study of chiral drug crystals: lattice energy calculations.
Li, Z J; Ojala, W H; Grant, D J
2001-10-01
The lattice energies of a number of chiral drugs with known crystal structures were calculated using Dreiding II force field. The lattice energies, including van der Waals, Coulombic, and hydrogen-bonding energies, of homochiral and racemic crystals of some ephedrine derivatives and of several other chiral drugs, are compared. The calculated energies are correlated with experimental data to probe the underlying intermolecular forces responsible for the formation of racemic species, racemic conglomerates, or racemic compounds, termed chiral discrimination. Comparison of the calculated energies among ephedrine derivatives reveals that a greater Coulombic energy corresponds to a higher melting temperature, while a greater van der Waals energy corresponds to a larger enthalpy of fusion. For seven pairs of homochiral and racemic compounds, correlation of the differences between the two forms in the calculated energies and experimental enthalpy of fusion suggests that the van der Waals interactions play a key role in the chiral discrimination in the crystalline state. For salts of the chiral drugs, the counter ions diminish chiral discrimination by increasing the Coulombic interactions. This result may explain why salt forms favor the formation of racemic conglomerates, thereby facilitating the resolution of racemates.
Perturbation theory calculations of model pair potential systems
Energy Technology Data Exchange (ETDEWEB)
Gong, Jianwu [Iowa State Univ., Ames, IA (United States)
2016-01-01
Helmholtz free energy is one of the most important thermodynamic properties for condensed matter systems. It is closely related to other thermodynamic properties such as chemical potential and compressibility. It is also the starting point for studies of interfacial properties and phase coexistence if free energies of different phases can be obtained. In this thesis, we will use an approach based on the Weeks-Chandler-Anderson (WCA) perturbation theory to calculate the free energy of both solid and liquid phases of Lennard-Jones pair potential systems and the free energy of liquid states of Yukawa pair potentials. Our results indicate that the perturbation theory provides an accurate approach to the free energy calculations of liquid and solid phases based upon comparisons with results from molecular dynamics (MD) and Monte Carlo (MC) simulations.
Energy Technology Data Exchange (ETDEWEB)
Moeller, M. P.; Urbanik, II, T.; Desrosiers, A. E.
1982-03-01
This paper describes the methodology and application of the computer model CLEAR (Calculates Logical Evacuation And Response) which estimates the time required for a specific population density and distribution to evacuate an area using a specific transportation network. The CLEAR model simulates vehicle departure and movement on a transportation network according to the conditions and consequences of traffic flow. These include handling vehicles at intersecting road segments, calculating the velocity of travel on a road segment as a function of its vehicle density, and accounting for the delay of vehicles in traffic queues. The program also models the distribution of times required by individuals to prepare for an evacuation. In order to test its accuracy, the CLEAR model was used to estimate evacuatlon tlmes for the emergency planning zone surrounding the Beaver Valley Nuclear Power Plant. The Beaver Valley site was selected because evacuation time estimates had previously been prepared by the licensee, Duquesne Light, as well as by the Federal Emergency Management Agency and the Pennsylvania Emergency Management Agency. A lack of documentation prevented a detailed comparison of the estimates based on the CLEAR model and those obtained by Duquesne Light. However, the CLEAR model results compared favorably with the estimates prepared by the other two agencies.
Tian, Zhen; Folkerts, Michael; Shi, Feng; Jiang, Steve B; Jia, Xun
2015-01-01
Monte Carlo (MC) simulation is considered as the most accurate method for radiation dose calculations. Accuracy of a source model for a linear accelerator is critical for the overall dose calculation accuracy. In this paper, we presented an analytical source model that we recently developed for GPU-based MC dose calculations. A key concept called phase-space-ring (PSR) was proposed. It contained a group of particles that are of the same type and close in energy and radial distance to the center of the phase-space plane. The model parameterized probability densities of particle location, direction and energy for each primary photon PSR, scattered photon PSR and electron PSR. For a primary photon PSRs, the particle direction is assumed to be from the beam spot. A finite spot size is modeled with a 2D Gaussian distribution. For a scattered photon PSR, multiple Gaussian components were used to model the particle direction. The direction distribution of an electron PSRs was also modeled as a 2D Gaussian distributi...
Energy Technology Data Exchange (ETDEWEB)
Jin, L; Eldib, A; Li, J; Price, R; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)
2015-06-15
Purpose: Uneven nose surfaces and air cavities underneath and the use of bolus present complexity and dose uncertainty when using a single electron energy beam to plan treatments of nose skin with a pencil beam-based planning system. This work demonstrates more accurate dose calculation and more optimal planning using energy and intensity modulated electron radiotherapy (MERT) delivered with a pMLC. Methods: An in-house developed Monte Carlo (MC)-based dose calculation/optimization planning system was employed for treatment planning. Phase space data (6, 9, 12 and 15 MeV) were used as an input source for MC dose calculations for the linac. To reduce the scatter-caused penumbra, a short SSD (61 cm) was used. Our previous work demonstrates good agreement in percentage depth dose and off-axis dose between calculations and film measurement for various field sizes. A MERT plan was generated for treating the nose skin using a patient geometry and a dose volume histogram (DVH) was obtained. The work also shows the comparison of 2D dose distributions between a clinically used conventional single electron energy plan and the MERT plan. Results: The MERT plan resulted in improved target dose coverage as compared to the conventional plan, which demonstrated a target dose deficit at the field edge. The conventional plan showed higher dose normal tissue irradiation underneath the nose skin while the MERT plan resulted in improved conformity and thus reduces normal tissue dose. Conclusion: This preliminary work illustrates that MC-based MERT planning is a promising technique in treating nose skin, not only providing more accurate dose calculation, but also offering an improved target dose coverage and conformity. In addition, this technique may eliminate the necessity of bolus, which often produces dose delivery uncertainty due to the air gaps that may exist between the bolus and skin.
An effective model for dynamic finite difference calculations
Energy Technology Data Exchange (ETDEWEB)
Dey, T.N.
1996-01-01
An effective stress model, which simulates the mechanical effects of pore fluids on deformation and strength of porous materials, is described. The model can directly use SESAME table equations-of-state (EOSs) for the solid and fluid components. the model assumes that undrained (no fluid flow) conditions occur. Elastic and crushing behavior of the pore space can be specified from the results of simple laboratory tests. The model fully couples deviatoric and volumetric behavior in the sense that deviatoric and tensile failure depend on the effective pressure, while volumetric changes caused by deviatoric failure are coupled back to the volumetric behavior of the material. Strain hardening and softening of the yield surface, together with a number of flow rules, can be modeled. This model has been implemented into the SMC123 and CTH codes.
Two-phase relative permeability models in reservoir engineering calculations
Energy Technology Data Exchange (ETDEWEB)
Siddiqui, S.; Hicks, P.J.; Ertekin, T.
1999-01-15
A comparison of ten two-phase relative permeability models is conducted using experimental, semianalytical and numerical approaches. Model predicted relative permeabilities are compared with data from 12 steady-state experiments on Berea and Brown sandstones using combinations of three white mineral oils and 2% CaCl1 brine. The model results are compared against the experimental data using three different criteria. The models are found to predict the relative permeability to oil, relative permeability to water and fractional flow of water with varying degrees of success. Relative permeability data from four of the experimental runs are used to predict the displacement performance under Buckley-Leverett conditions and the results are compared against those predicted by the models. Finally, waterflooding performances predicted by the models are analyzed at three different viscosity ratios using a two-dimensional, two-phase numerical reservoir simulator. (author)
Chemically reacting supersonic flow calculation using an assumed PDF model
Farshchi, M.
1990-01-01
This work is motivated by the need to develop accurate models for chemically reacting compressible turbulent flow fields that are present in a typical supersonic combustion ramjet (SCRAMJET) engine. In this paper the development of a new assumed probability density function (PDF) reaction model for supersonic turbulent diffusion flames and its implementation into an efficient Navier-Stokes solver are discussed. The application of this model to a supersonic hydrogen-air flame will be considered.
Extraproximal approach to calculating equilibriums in pure exchange models
Antipin, A. S.
2006-10-01
Models of economic equilibrium are a powerful tool of mathematical modeling of various markets. However, according to many publications, there are as yet no universal techniques for finding equilibrium prices that are solutions to such models. A technique of this kind that is a natural implementation of the Walras idea of tatonnements (i.e., groping for equilibrium prices) is proposed, and its convergence is proved.
Long-Term Calculations with Large Air Pollution Models
DEFF Research Database (Denmark)
1999-01-01
Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998......Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998...
Long-Term Calculations with Large Air Pollution Models
DEFF Research Database (Denmark)
1999-01-01
Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998......Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998...
QSAR models for anti-androgenic effect - a preliminary study
DEFF Research Database (Denmark)
Jensen, Gunde Egeskov; Nikolov, Nikolai Georgiev; Wedebye, Eva Bay;
2011-01-01
of the model for a particular application, balance of training sets, domain definition, and cut-offs for prediction interpretation should also be taken into account. Different descriptors in the modelling systems are illustrated with hydroxyflutamide and dexamethasone as examples (a non-steroid and a steroid......Three modelling systems (MultiCase (R), LeadScope (R) and MDL (R) QSAR) were used for construction of androgenic receptor antagonist models. There were 923-942 chemicals in the training sets. The models were cross-validated (leave-groups-out) with concordances of 77-81%, specificity of 78...
Preliminary Modeling and Simulation Study on Olfactory Cell Sensation
Zhou, Jun; Yang, Wei; Chen, Peihua; Liu, Qingjun; Wang, Ping
2009-05-01
This paper introduced olfactory sensory neuron's whole-cell model with a concrete voltage-gated ionic channels and simulation. Though there are many models in olfactory sensory neuron and olfactory bulb, it remains uncertain how they express the logic of olfactory information processing. In this article, the olfactory neural network model is also introduced. This model specifies the connections among neural ensembles of the olfactory system. The simulation results of the neural network model are consistent with the observed olfactory biological characteristics such as 1/f-type power spectrum and oscillations.
Preliminary Calculation of the EROI for the Production of Crude Oil and Light Oil Products in Russia
Directory of Open Access Journals (Sweden)
Alexander Safronov
2014-09-01
Full Text Available Russia is one of the world’s largest producers of energy resources. The production of energy resources in Russia is profitable both economically and in terms of energy production. Currently, Russian oil and gas companies have a policy of increasing energy efficiency, which will led to an increase in the energy return on investment (EROI of both oil and gas production as a whole, and of separate companies in particular. By our calculations, the EROI for oil production in Russia differs for the different companies, and in 2012 was in the range of 22–35:1. The EROI for light oil products in 2012 was in the range of 5–13:1.
Institute of Scientific and Technical Information of China (English)
DU Jinglong; GAO Ang; YANG Shilun; ZHANG Wenxiang; ZHAO Huayun; LI Peng
2005-01-01
The estuary and coast is an area where the land and the sea interact and a place in which human beings frequently move about so that understanding and controlling the change and development modes of the coastal landform plays a vital part in exploiting and protecting coastal resources. A model is the generalization and abstraction of objective things. This paper summarizes four methods for the landform development of the tidal shore and underwater delta, mainly discusses the model's structural elements, and presents their specific application on the basis of the authors' case study. With the application of the profile model, the dynamic change of coastal landform can be clearly seen by contrasting the different profiles of different years.Through the shrinking, expanding and transformation of the isobath, plane model is used to study the macro-change of the shoal and the coastal landform. Speed model is an efficient means to analyze the trend of erosion and deposition and the local change in a great area of the sea. Statistical survey model is a static analysis, which can be used to establish the relationship between the erosion and deposition of the shoal and the altitude and slope of survey spot.
Carbon fiber dispersion models used for risk analysis calculations
1979-01-01
For evaluating the downwind, ground level exposure contours from carbon fiber dispersion, two fiber release scenarios were chosen. The first is the fire and explosion release in which all of the fibers are released instantaneously. This model applies to accident scenarios where an explosion follows a short-duration fire in the aftermath of the accident. The second is the plume release scenario in which the total mass of fibers is released into the fire plume. This model applies to aircraft accidents where only a fire results. These models are described in detail.
Mooring Model Experiment and Mooring Line Force Calculation
Institute of Scientific and Technical Information of China (English)
向溢; 谭家华; 杨建民; 张承懿
2001-01-01
Mooring model experiment and mooring line tension determination are of significance to the design of mooring systems and berthing structures. This paper mainly involves: (a) description and analysis of a mooring model experiment;(b) derivation of static equilibrium equations for a moored ship subjected to wind, current and waves; (c) solution of mo.oring equations with the Monte Carlo method; (d) qualitative analysis of effects of pier piles on mooring line forces. Special emphasis is placed on the derivation ofstatic equilibrium equations, solution method and the mooring model experiment.
Dekker, C. M.; Sliggers, C. J.
To spur on quality assurance for models that calculate air pollution, quality criteria for such models have been formulated. By satisfying these criteria the developers of these models and producers of the software packages in this field can assure and account for the quality of their products. In this way critics and users of such (computer) models can gain a clear understanding of the quality of the model. Quality criteria have been formulated for the development of mathematical models, for their programming—including user-friendliness, and for the after-sales service, which is part of the distribution of such software packages. The criteria have been introduced into national and international frameworks to obtain standardization.
Mathematical model partitioning and packing for parallel computer calculation
Arpasi, Dale J.; Milner, Edward J.
1986-01-01
This paper deals with the development of multiprocessor simulations from a serial set of ordinary differential equations describing a physical system. The identification of computational parallelism within the model equations is discussed. A technique is presented for identifying this parallelism and for partitioning the equations for parallel solution on a multiprocessor. Next, an algorithm which packs the equations into a minimum number of processors is described. The results of applying the packing algorithm to a turboshaft engine model are presented.
The Martian Plasma Environment: Model Calculations and Observations
Lichtenegger, H. I. M.; Dubinin, E.; Schwingenschuh, K.; Riedler, W.
Based on a modified version of the model of an induced martian magnetosphere developed by Luhmann (1990), the dynamics and spatial distribution of different planetary ion species is examined. Three main regions are identified: A cloud of ions travelling along cycloidal trajectories, a plasma mantle and a plasma sheet. The latter predominantly consists of oxygen ions of ionospheric origin with minor portions of light particles. Comparison of model results with Phobos-2 observations shows reasonable agreement.
Energy Technology Data Exchange (ETDEWEB)
Farkas, Istvan; Hutli, Ezddin; Faekas, Tatiana; Takacs, Antal; Guba, Attila; Toth, Ivan [Dept. of Thermohydraulics, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary)
2016-08-15
The aim of this work is to simulate the thermohydraulic consequences of a main steam line break and to compare the obtained results with Rossendorf Coolant Mixing Model (ROCOM) 1.1 experimental results. The objective is to utilize data from steady-state mixing experiments and computational fluid dynamics (CFD) calculations to determine the flow distribution and the effect of thermal mixing phenomena in the primary loops for the improvement of normal operation conditions and structural integrity assessment of pressurized water reactors. The numerical model of ROCOM was developed using the FLUENT code. The positions of the inlet and outlet boundary conditions and the distribution of detailed velocity/turbulence parameters were determined by preliminary calculations. The temperature fields of transient calculation were averaged in time and compared with time-averaged experimental data. The perforated barrel under the core inlet homogenizes the flow, and therefore, a uniform temperature distribution is formed in the pressure vessel bottom. The calculated and measured values of lowest temperature were equal. The inlet temperature is an essential parameter for safety assessment. The calculation predicts precisely the experimental results at the core inlet central region. CFD results showed a good agreement (both qualitatively and quantitatively) with experimental results.
Modeling and Testing of EVs - Preliminary Study and Laboratory Development
DEFF Research Database (Denmark)
Yang, Guang-Ya; Marra, Francesco; Nielsen, Arne Hejde;
2010-01-01
Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid...... tests, followed by the suggestions towards a feasible battery model for further studies....
Lattice location of dopant atoms: An -body model calculation
Indian Academy of Sciences (India)
N K Deepak
2010-03-01
The channelling and scattering yields of 1 MeV -particles in the $\\langle 1 0 0 \\rangle$, $\\langle 1 1 0 \\rangle and $\\langle 1 1 1 \\rangle$ directions of silicon implanted with bismuth and ytterbium have been simulated using -body model. The close encounter yield from dopant atoms in silicon is determined from the flux density, using the Bontemps and Fontenille method. All previous works reported in literature so far have been done with computer programmes using a statistical analytical expression or by a binary collision model or a continuum model. These results at the best gave only the transverse displacement of the lattice site from the concerned channelling direction. Here we applied the superior -body model to study the yield from bismuth in silicon. The finding that bismuth atom occupies a position close to the silicon substitutional site is new. The transverse displacement of the suggested lattice site from the channelling direction is consistent with the experimental results. The above model is also applied to determine the location of ytterbium in silicon. The present values show good agreement with the experimental results.
An hydrodynamic model for the calculation of oil spills trajectories
Energy Technology Data Exchange (ETDEWEB)
Paladino, Emilio Ernesto; Maliska, Clovis Raimundo [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica. Lab. de Dinamica dos Fluidos Computacionais]. E-mails: emilio@sinmec.ufsc.br; maliska@sinmec.ufsc.br
2000-07-01
The aim of this paper is to present a mathematical model and its numerical treatment to forecast oil spills trajectories in the sea. The knowledge of the trajectory followed by an oil slick spilled on the sea is of fundamental importance in the estimation of potential risks for pipeline and tankers route selection, and in combating the pollution using floating barriers, detergents, etc. In order to estimate these slicks trajectories a new model, based on the mass and momentum conservation equations is presented. The model considers the spreading in the regimes when the inertial and viscous forces counterbalance gravity and takes into account the effects of winds and water currents. The inertial forces are considered for the spreading and the displacement of the oil slick, i.e., is considered its effects on the movement of the mass center of the slick. The mass loss caused by oil evaporation is also taken into account. The numerical model is developed in generalized coordinates, making the model easily applicable to complex coastal geographies. (author)
Gonzálvez, Alicia G; González Ureña, Ángel
2012-10-01
A laser spectroscopic technique is described that combines transmission and resonance-enhanced Raman inelastic scattering together with low laser power (view, a model for the Raman signal dependence on the sample thickness is also presented. Essentially, the model considers the sample to be homogeneous and describes the underlying physics using only three parameters: the Raman cross-section, the laser-radiation attenuation cross-section, and the Raman signal attenuation cross-section. The model was applied successfully to describe the sample-size dependence of the Raman signal in both β-carotene standards and carrot roots. The present technique could be useful for direct, fast, and nondestructive investigations in food quality control and analytical or physiological studies of animal and human tissues.
Wave-current interactions: model development and preliminary results
Mayet, Clement; Lyard, Florent; Ardhuin, Fabrice
2013-04-01
The coastal area concentrates many uses that require integrated management based on diagnostic and predictive tools to understand and anticipate the future of pollution from land or sea, and learn more about natural hazards at sea or activity on the coast. The realistic modelling of coastal hydrodynamics needs to take into account various processes which interact, including tides, surges, and sea state (Wolf [2008]). These processes act at different spatial scales. Unstructured-grid models have shown the ability to satisfy these needs, given that a good mesh resolution criterion is used. We worked on adding a sea state forcing in a hydrodynamic circulation model. The sea state model is the unstructured version of WAVEWATCH III c (Tolman [2008]) (which version is developed at IFREMER, Brest (Ardhuin et al. [2010]) ), and the hydrodynamic model is the 2D barotropic module of the unstructured-grid finite element model T-UGOm (Le Bars et al. [2010]). We chose to use the radiation stress approach (Longuet-Higgins and Stewart [1964]) to represent the effect of surface waves (wind waves and swell) in the barotropic model, as previously done by Mastenbroek et al. [1993]and others. We present here some validation of the model against academic cases : a 2D plane beach (Haas and Warner [2009]) and a simple bathymetric step with analytic solution for waves (Ardhuin et al. [2008]). In a second part we present realistic application in the Ushant Sea during extreme event. References Ardhuin, F., N. Rascle, and K. Belibassakis, Explicit wave-averaged primitive equations using a generalized Lagrangian mean, Ocean Modelling, 20 (1), 35-60, doi:10.1016/j.ocemod.2007.07.001, 2008. Ardhuin, F., et al., Semiempirical Dissipation Source Functions for Ocean Waves. Part I: Definition, Calibration, and Validation, J. Phys. Oceanogr., 40 (9), 1917-1941, doi:10.1175/2010JPO4324.1, 2010. Haas, K. A., and J. C. Warner, Comparing a quasi-3D to a full 3D nearshore circulation model: SHORECIRC and
A calculation model for the noise from steel railway bridges
Janssens, M.H.A.; Thompson, D.J.
1996-01-01
The sound level of a train crossing a steel railway bridge is usually about 10 dB higher than on plain track. In the Netherlands there are many such bridges which, for practical reasons, cannot be replaced by more intrinsically quiet concrete bridges. A computational model is described for the
A calculation model for the noise from steel railway bridges
Janssens, M.H.A.; Thompson, D.J.
1996-01-01
The sound level of a train crossing a steel railway bridge is usually about 10 dB higher than on plain track. In the Netherlands there are many such bridges which, for practical reasons, cannot be replaced by more intrinsically quiet concrete bridges. A computational model is described for the estim
Calculation of benchmarks with a shear beam model
Ferreira, D.
2015-01-01
Fiber models for beam and shell elements allow for relatively rapid finite element analysis of concrete structures and structural elements. This project aims at the development of the formulation of such elements and a pilot implementation. Standard nonlinear fiber beam formulations do not account
Glass viscosity calculation based on a global statistical modelling approach
Energy Technology Data Exchange (ETDEWEB)
Fluegel, Alex
2007-02-01
A global statistical glass viscosity model was developed for predicting the complete viscosity curve, based on more than 2200 composition-property data of silicate glasses from the scientific literature, including soda-lime-silica container and float glasses, TV panel glasses, borosilicate fiber wool and E type glasses, low expansion borosilicate glasses, glasses for nuclear waste vitrification, lead crystal glasses, binary alkali silicates, and various further compositions from over half a century. It is shown that within a measurement series from a specific laboratory the reported viscosity values are often over-estimated at higher temperatures due to alkali and boron oxide evaporation during the measurement and glass preparation, including data by Lakatos et al. (1972) and the recently published High temperature glass melt property database for process modeling by Seward et al. (2005). Similarly, in the glass transition range many experimental data of borosilicate glasses are reported too high due to phase separation effects. The developed global model corrects those errors. The model standard error was 9-17°C, with R^2 = 0.985-0.989. The prediction 95% confidence interval for glass in mass production largely depends on the glass composition of interest, the composition uncertainty, and the viscosity level. New insights in the mixed-alkali effect are provided.
Preliminaries to a Social-Semiotic Model of Communicative Action
Directory of Open Access Journals (Sweden)
Antonio SANDU
2015-12-01
Full Text Available The purpose of this article is to bring contributions to the elaboration of a social-semiotic model of social constructionism, which will make a synthesis between the theory of communicative action and the theories of social-constructionist semiotic model?, based on the postulation of a social universe in a network of communicative interdependencies developed on levels of reality. The interpretative model we propose comes to conceptualize the particularities of the sociological analysis of the transmodern society, seen as a knowledge-based society, placed at the interference with the postmodern society; that of generalized permissiveness. The model proposed aims at a constructionist-fractalic (al? analysis (of deconstruction-reconstruction type of the interpretative drift of social constructs, under the empire of different constructive instances.
Preliminary mixed-layer model results for FIRE marine stratocumulus IFO conditions
Barlow, R.; Nicholls, S.
1990-01-01
Some preliminary results from the Turton and Nicholls mixed layer model using typical FIRE boundary conditions are presented. The model includes entrainment and drizzle parametrizations as well as interactive long and shortwave radiation schemes. A constraint on the integrated turbulent kinetic energy balance ensures that the model remains energetically consistent at all times. The preliminary runs were used to identify the potentially important terms in the heat and moisture budgets of the cloud layer, and to assess the anticipated diurnal variability. These are compared with typical observations from the C130. Sensitivity studies also revealed the remarkable stability of these cloud sheets: a number of negative feedback mechanisms appear to operate to maintain the cloud over an extended time period. These are also discussed. The degree to which such a modelling approach can be used to explain observed features, the specification of boundary conditions and problems of interpretation in non-horizontally uniform conditions is also raised.
RHF RELAP5 model and preliminary loss-of-offsite-power simulation results for LEU conversion
Energy Technology Data Exchange (ETDEWEB)
Licht, J. R. [Argonne National Laboratory (ANL), Argonne, IL (United States). Nuclear Engineering Div.; Bergeron, A. [Argonne National Laboratory (ANL), Argonne, IL (United States). Nuclear Engineering Div.; Dionne, B. [Argonne National Laboratory (ANL), Argonne, IL (United States). Nuclear Engineering Div.; Thomas, F. [Institut Laue-Langevin (ILL), Grenoble (Switzerland). RHF Reactor Dept.
2014-08-01
The purpose of this document is to describe the current state of the RELAP5 model for the Institut Laue-Langevin High Flux Reactor (RHF) located in Grenoble, France, and provide an update to the key information required to complete, for example, simulations for a loss of offsite power (LOOP) accident. A previous status report identified a list of 22 items to be resolved in order to complete the RELAP5 model. Most of these items have been resolved by ANL and the RHF team. Enough information was available to perform preliminary safety analyses and define the key items that are still required. Section 2 of this document describes the RELAP5 model of RHF. The final part of this section briefly summarizes previous model issues and resolutions. Section 3 of this document describes preliminary LOOP simulations for both HEU and LEU fuel at beginning of cycle conditions.
RHF RELAP5 Model and Preliminary Loss-Of-Offsite-Power Simulation Results for LEU Conversion
Energy Technology Data Exchange (ETDEWEB)
Licht, J. R. [Argonne National Laboratory (ANL), Argonne, IL (United States). Nuclear Engineering Div.; Bergeron, A. [Argonne National Laboratory (ANL), Argonne, IL (United States). Nuclear Engineering Div.; Dionne, B. [Argonne National Laboratory (ANL), Argonne, IL (United States). Nuclear Engineering Div.; Thomas, F. [Institut Laue-Langevin (ILL), Grenoble (Switzerland). RHF Reactor Dept.
2014-08-01
The purpose of this document is to describe the current state of the RELAP5 model for the Institut Laue-Langevin High Flux Reactor (RHF) located in Grenoble, France, and provide an update to the key information required to complete, for example, simulations for a loss of offsite power (LOOP) accident. A previous status report identified a list of 22 items to be resolved in order to complete the RELAP5 model. Most of these items have been resolved by ANL and the RHF team. Enough information was available to perform preliminary safety analyses and define the key items that are still required. Section 2 of this document describes the RELAP5 model of RHF. The final part of this section briefly summarizes previous model issues and resolutions. Section 3 of this document describes preliminary LOOP simulations for both HEU and LEU fuel at beginning of cycle conditions.
Directory of Open Access Journals (Sweden)
Inseon Ryoo
Full Text Available PURPOSE: To evaluate the usefulness of dynamic susceptibility contrast (DSC enhanced perfusion MR imaging in predicting major genetic alterations in glioblastomas. MATERIALS AND METHODS: Twenty-five patients (M:F = 13∶12, mean age: 52.1±15.2 years with pathologically proven glioblastoma who underwent DSC MR imaging before surgery were included. On DSC MR imaging, the normalized relative tumor blood volume (nTBV of the enhancing solid portion of each tumor was calculated by using dedicated software (Nordic TumorEX, NordicNeuroLab, Bergen, Norway that enabled semi-automatic segmentation for each tumor. Five major glioblastoma genetic alterations (epidermal growth factor receptor (EGFR, phosphatase and tensin homologue (PTEN, Ki-67, O6-methylguanine-DNA methyltransferase (MGMT and p53 were confirmed by immunohistochemistry and analyzed for correlation with the nTBV of each tumor. Statistical analysis was performed using the unpaired Student t test, ROC (receiver operating characteristic curve analysis and Pearson correlation analysis. RESULTS: The nTBVs of the MGMT methylation-negative group (mean 9.5±7.5 were significantly higher than those of the MGMT methylation-positive group (mean 5.4±1.8 (p = .046. In the analysis of EGFR expression-positive group, the nTBVs of the subgroup with loss of PTEN gene expression (mean: 10.3±8.1 were also significantly higher than those of the subgroup without loss of PTEN gene expression (mean: 5.6±2.3 (p = .046. Ki-67 labeling index indicated significant positive correlation with the nTBV of the tumor (p = .01. CONCLUSION: We found that glioblastomas with aggressive genetic alterations tended to have a high nTBV in the present study. Thus, we believe that DSC-enhanced perfusion MR imaging could be helpful in predicting genetic alterations that are crucial in predicting the prognosis of and selecting tailored treatment for glioblastoma patients.
Aeroelastic Calculations Using CFD for a Typical Business Jet Model
Gibbons, Michael D.
1996-01-01
Two time-accurate Computational Fluid Dynamics (CFD) codes were used to compute several flutter points for a typical business jet model. The model consisted of a rigid fuselage with a flexible semispan wing and was tested in the Transonic Dynamics Tunnel at NASA Langley Research Center where experimental flutter data were obtained from M(sub infinity) = 0.628 to M(sub infinity) = 0.888. The computational results were computed using CFD codes based on the inviscid TSD equation (CAP-TSD) and the Euler/Navier-Stokes equations (CFL3D-AE). Comparisons are made between analytical results and with experiment where appropriate. The results presented here show that the Navier-Stokes method is required near the transonic dip due to the strong viscous effects while the TSD and Euler methods used here provide good results at the lower Mach numbers.
Preliminary results of a three-dimensional radiative transfer model
Energy Technology Data Exchange (ETDEWEB)
O`Hirok, W. [Univ. of California, Santa Barbara, CA (United States)
1995-09-01
Clouds act as the primary modulator of the Earth`s radiation at the top of the atmosphere, within the atmospheric column, and at the Earth`s surface. They interact with both shortwave and longwave radiation, but it is primarily in the case of shortwave where most of the uncertainty lies because of the difficulties in treating scattered solar radiation. To understand cloud-radiative interactions, radiative transfer models portray clouds as plane-parallel homogeneous entities to ease the computational physics. Unfortunately, clouds are far from being homogeneous, and large differences between measurement and theory point to a stronger need to understand and model cloud macrophysical properties. In an attempt to better comprehend the role of cloud morphology on the 3-dimensional radiation field, a Monte Carlo model has been developed. This model can simulate broadband shortwave radiation fluxes while incorporating all of the major atmospheric constituents. The model is used to investigate the cloud absorption anomaly where cloud absorption measurements exceed theoretical estimates and to examine the efficacy of ERBE measurements and cloud field experiments. 3 figs.
IEA-ETSAP TIMES models in Denmark. Preliminary edition
Energy Technology Data Exchange (ETDEWEB)
Grohnheit, P.E.
2011-03-15
This report presents the project 'Danish participation in IEAETSAP, Annex XI, 2008-2010', which continued the Danish participation in ETSAP under Annex XI 'JOint STudies for New And Mitigated Energy Systems (JOSTNAMES): Climate friendly, Secure and Productive Energy Systems'. The main activity has been semi-annual workshops focusing on presentations of model analyses and use of the ETSAP tools (the MARKAL/TIMES family of models). Contributions to these workshops have been based on various collaborative projects within the EU research programmes and the Danish Centre for Environment, Energy and Health (CEEH). In addition, the DTU Climate Centre at Risoe, which was founded in the autumn of 2008, has taken part in the ETSAP workshops, and used the ETSAP model tools for projects, papers, and presentations, as well as for a Ph.D. project. (Author)
Preliminary Functional-Structural Modeling on Poplar (Salicaceae)
Liu, Dongxiang; Letort, Véronique; Xing, Meijun; Gang, Yang; Huang, Xinyuan; Cao, Weiqun
2010-01-01
Poplar is one of the best fast-growing trees in the world, widely used for windbreak and wood product. Although architecture of poplar has direct impact on its applications, it has not been descried in previous poplar models, probably because of the difficulties raised by measurement, data processing and parameterization. In this paper, the functional-structural model GreenLab is calibrated by using poplar data of 3, 4, 5, 6 years old. The data was acquired by simplifying measurement. The architecture was also simplified by classifying the branches into several types (physiological age) using clustering analysis, which decrease the number of parameters. By multi-fitting the sampled data of each tree, the model parameters were identified and the plant architectures at different tree ages were simulated.
Some vaccination strategies for the SEIR epidemic model. Preliminary results
De la Sen, M; Alonso-Quesada, S
2011-01-01
This paper presents a vaccination-based control strategy for a SEIR (susceptible plus infected plus infectious plus removed populations) propagation disease model. The model takes into account the total population amounts as a refrain for the illness transmission since its increase makes more difficult contacts among susceptible and infected. The control objective is the asymptotically tracking of the removed-by-immunity population to the total population while achieving simultaneously the remaining population (i.e. susceptible plus infected plus infectious) to asymptotically tend to zero.
Institute of Scientific and Technical Information of China (English)
陈建彬; 吕小强
2011-01-01
Aiming at the fact that the energy and mass exchange phenomena exist between barrel and gas-operated device of the automatic weapon, for describing its interior ballistics and dynamic characteristics of the gas-operated device accurately, a new variable-mass thermodynamics model is built. It is used to calculate the automatic mechanism velocity of a certain automatic weapon, the calculation results coincide with the experimental results better, and thus the model is validated. The influences of structure parameters on gas-operated device＇ s dynamic characteristics are discussed. It shows that the model is valuable for design and accurate performance prediction of gas-operated automatic weapon.
Energy Technology Data Exchange (ETDEWEB)
Andreani-Aksoyoglu, S.; Keller, J. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)
1999-08-01
In the frame of the comprehensive assessment of Swiss energy systems, air quality simulations were performed by using a 3-dimensional photo-chemical dispersion model. The objective is to investigate the impacts of pollutants in Switzerland for future options of Swiss energy systems. Four scenarios were investigated: Base Case: simulations with the projected emissions for the year 2030, Scenario 1) all nuclear power plants were replaced by oil-driven combined cycle plants (CCP), Scenarios 2 to 4) traffic emissions were reduced in whole Switzerland as well as in the cities and on the highways separately. Changes in the pollutant concentrations and depositions, and the possible short-term impacts are discussed on the basis of exceedences of critical levels for plants and limits given to protect the public health. (author) 2 figs., 7 refs.
Simulating lightning into the RAMS model: implementation and preliminary results
Directory of Open Access Journals (Sweden)
S. Federico
2014-05-01
Full Text Available This paper shows the results of a tailored version of a previously published methodology, designed to simulate lightning activity, implemented into the Regional Atmospheric Modeling System (RAMS. The method gives the flash density at the resolution of the RAMS grid-scale allowing for a detailed analysis of the evolution of simulated lightning activity. The system is applied in detail to two case studies occurred over the Lazio Region, in Central Italy. Simulations are compared with the lightning activity detected by the LINET network. The cases refer to two thunderstorms of different intensity. Results show that the model predicts reasonably well both cases and that the lightning activity is well reproduced especially for the most intense case. However, there are errors in timing and positioning of the convection, whose magnitude depends on the case study, which mirrors in timing and positioning errors of the lightning distribution. To assess objectively the performance of the methodology, standard scores are presented for four additional case studies. Scores show the ability of the methodology to simulate the daily lightning activity for different spatial scales and for two different minimum thresholds of flash number density. The performance decreases at finer spatial scales and for higher thresholds. The comparison of simulated and observed lighting activity is an immediate and powerful tool to assess the model ability to reproduce the intensity and the evolution of the convection. This shows the importance of the use of computationally efficient lightning schemes, such as the one described in this paper, in forecast models.
Preliminary development of the Active Colonoscopy Training Model
Directory of Open Access Journals (Sweden)
Choi J
2011-06-01
Full Text Available JungHun Choi1, Kale Ravindra1, Randolph Robert1, David Drozek21Mechanical Engineering, Ohio University, Athens, OH, USA; 2College of Osteopathic Medicine, Ohio University, Athens, OH, USAAbstract: Formal colonoscopy training requires a significant amount of time and effort. In particular, it requires actual patients for a realistic learning experience. The quality of colonoscopy training varies, and includes didactic courses and procedures proctored by skilled surgeons. A colonoscopy training model is occasionally used as part of the training method, but the effects are minute due to both the simple and tedious training procedures. To enhance the educational effect of the colonoscopy training model, the Active Colonoscopy Training Model (ACTM has been developed. ACTM is an interactive colonoscopy training device which can create the environment of a real colonoscopy procedure as closely as possible. It comprises a configurable rubber colon, a human torso, sensors, a display, and the control part. The ACTM provides audio and visual interaction to the trainee by monitoring important factors, such as forces caused by the distal tip and the shaft of the colonoscope and the pressure to open up the lumen and the localization of the distal tip. On the computer screen, the trainee can easily monitor the status of the colonoscopy, which includes the localization of the distal tip, maximum forces, pressure inside the colon, and surgery time. The forces between the rubber colon and the constraints inside the ACTM are measured and the real time display shows the results to the trainee. The pressure sensors will check the pressure at different parts of the colon. The real-time localized distal tip gives the colonoscopy trainee easier and more confident operation without introducing an additional device in the colonoscope. With the current need for colonoscopists and physicians, the ACTM can play an essential role resolving the problems of the current
Nuclear model calculations and their role in space radiation research
Townsend, L. W.; Cucinotta, F. A.; Heilbronn, L. H.
2002-01-01
Proper assessments of spacecraft shielding requirements and concomitant estimates of risk to spacecraft crews from energetic space radiation requires accurate, quantitative methods of characterizing the compositional changes in these radiation fields as they pass through thick absorbers. These quantitative methods are also needed for characterizing accelerator beams used in space radiobiology studies. Because of the impracticality/impossibility of measuring these altered radiation fields inside critical internal body organs of biological test specimens and humans, computational methods rather than direct measurements must be used. Since composition changes in the fields arise from nuclear interaction processes (elastic, inelastic and breakup), knowledge of the appropriate cross sections and spectra must be available. Experiments alone cannot provide the necessary cross section and secondary particle (neutron and charged particle) spectral data because of the large number of nuclear species and wide range of energies involved in space radiation research. Hence, nuclear models are needed. In this paper current methods of predicting total and absorption cross sections and secondary particle (neutrons and ions) yields and spectra for space radiation protection analyses are reviewed. Model shortcomings are discussed and future needs presented. c2002 COSPAR. Published by Elsevier Science Ltd. All right reserved.
Preliminary modelling study of ice accretion on wind turbines
DEFF Research Database (Denmark)
Pedersen, Marie Cecilie; Yin, Chungen
2014-01-01
One of the main challenges associated with cold-climate wind energy is icing on wind turbines and a series of icing-induced problems such as production loss, blade fatigue and safety issues. Because of the difficulties with on-site measurements, simulations are often used to understand and predict...... icing events. In this paper, a new methodology for prediction of icing-induced production loss is proposed, from which the fundamentals of ice accretion on wind turbines can be better understood and the operational production losses can be more reliably predicted. Computational fluid dynamics (CFD......) modelling of ice accretion on wind turbines is also performed for different ice events, resulting in a reliable framework for CFD-based ice accretion modelling which is one of the key elements in the new methodology....
Vaccination strategies for SEIR models using feedback linearization. Preliminary results
De la Sen, M; Alonso-Quesada, S
2011-01-01
A linearization-based feedback-control strategy for a SEIR epidemic model is discussed. The vaccination objective is the asymptotically tracking of the removed-by-immunity population to the total population while achieving simultaneously the remaining population (i.e. susceptible plus infected plus infectious) to asymptotically tend to zero. The disease controlpolicy is designed based on a feedback linearization technique which provides a general method to generate families of vaccination policies with sound technical background.
A Preliminary Evaluation of Bandwidth Allocation Model Dynamic Switching
Directory of Open Access Journals (Sweden)
Rafael F. Reale
2014-06-01
Full Text Available Bandwidth Allocation Models (BAMs are used in order to define Bandwidth Constraints (BCs in a per-class basis for MPLS/DS-TE networks and effectively define how network resources like bandwidth are obtained and shared by applications. The BAMs proposed (MAM – Maximum Allocation Model, RDM – Russian Dolls Model, G-RDM – Generic RDM and AllocTC-Sharing attempt to optimize the use of bandwidth resources on a per-link basis with different allocation and resource sharing characteristics. As such, the adoption of distinct BAMs and/or changes in network resource demands (network traffic profile may result in different network traffic allocation and operational behavior for distinct BAMs. This paper evaluates the resulting network characteristics (li nk utilization, preemption and flows blocking of using BAMs dynamically with different traffic scenarios. In brief, it is investigated the dynamics of BAM switching with distinct traffic scenarios. The paper presents initially the investigated BAMs in relation to their behavior and resource allocation characteristics. Then, distinct BAMs are compared using different traffic scenarios in order to investigate the impact of a dynamic change of the BAM configured in the network. Finally, the paper shows that the adoption of a dynamic BAM allocation strategy may result in benefits for network operation in terms of link utilization, preemption and flows blocking.
A preliminary study of periodontitis and vascular calcification compound model
Institute of Scientific and Technical Information of China (English)
MENGYun; DENGJing; PanKe-qing
2015-01-01
Objective This experiment is desired to establish a compound model of chronic periodontitis and vascular calcification,so as to study the relation of periodontal and vascular calcification.Methods Forty male Wistar rats were randomly divided into:control group(group C),periodontitis group(group CP),vascular calcification group(group VDN),compound group (group CP+VDN).Every groups accepted the corresponding manages to establish the animal model.Eight weeks later,al the rats were sacrificed and the fol owing items were observed:inflam-matory factor in serum were tested,Hematoxylin-eosin staining(HE)staining of vascular tissue were taken to test.Results Through detection of periodontal tissue,serum and vascular tissue,an-imal models were successful.Histopathologic observation revealed:obvious inflammation of periodontal tissue was obversed in group CP and CP+VDN.The red Mineralized nodules deposition in group VDN and CP+VDN were higher than in group C and CP(P<0.05)by HE staining,and that in group CP+VDN was significantly higher than in group VDN(P<0.05);Animals in group CP+VDN showed higher level of IL-1 in serum than that in group CP,VDN and C.Conclusion This study has demonstrated that periodontitis have some promoting ef ect on vascular cal-cification.
Jamaludin, Amril Hadri; Karim, Nurulzatushima Abdul; Noor, Raja Nor Husna Raja Mohd; Othman, Nurulhidayah; Malik, Sulaiman Abdul
2017-08-01
Construction waste management (CWM) is the practice of minimizing and diverting construction waste, demolition debris, and land-clearing debris from disposal and redirecting recyclable resources back into the construction process. Best practice model means best choice from the collection of other practices that was built for purpose of construction waste management. The practice model can help the contractors in minimizing waste before the construction activities will be started. The importance of minimizing wastage will have direct impact on time, cost and quality of a construction project. This paper is focusing on the preliminary study to determine the factors of waste generation in the construction sites and identify the effectiveness of existing construction waste management practice conducted in Malaysia. The paper will also include the preliminary works of planned research location, data collection method, and analysis to be done by using the Analytical Hierarchy Process (AHP) to help in developing suitable waste management best practice model that can be used in the country.
Modelled and Observed Diurnal SST Signals: "SSTDV:R.EX.-IM.A.M." Project Preliminary Results
DEFF Research Database (Denmark)
Karagali, Ioanna; Høyer, Jacob; LeBorgne, Pierre
2013-01-01
This study presents some of the preliminary results from the ESA Support To Science Element (STSE) funded project on the Diurnal Variability of the Sea Surface Temperature, regarding its Regional Extend and Implications in Atmospheric Modelling (SSTDV:R.EX.–IM.A.M.). During this phase...... of the project, the focus is on the regional extend of diurnal variability. Particularly, extensive sensitivity tests regarding the definition of SSTfound fields show that using only quality 5 SEVIRI data results in warmer foundation fields SSTfound while there is an added ∼0.2 K variability when using multi...... Ocean Turbulence Model (GOTM) is applied. Preliminary results show that the initial temperature profiles may give a warmer start-up in the model while the light extinction scheme is a controlling factor for the amplitude and vertical extend of the daily signal....
User Guide for GoldSim Model to Calculate PA/CA Doses and Limits
Energy Technology Data Exchange (ETDEWEB)
Smith, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2016-10-31
A model to calculate doses for solid waste disposal at the Savannah River Site (SRS) and corresponding disposal limits has been developed using the GoldSim commercial software. The model implements the dose calculations documented in SRNL-STI-2015-00056, Rev. 0 “Dose Calculation Methodology and Data for Solid Waste Performance Assessment (PA) and Composite Analysis (CA) at the Savannah River Site”.
Preliminary Modeling of Accident Tolerant Fuel Concepts under Accident Conditions
Energy Technology Data Exchange (ETDEWEB)
Gamble, Kyle A.; Hales, Jason D.
2016-12-01
The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. Thus, the United States Department of Energy through its NEAMS (Nuclear Energy Advanced Modeling and Simulation) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is funded for a three-year period. The purpose of the HIP is to perform research into two potential accident tolerant concepts and provide an in-depth report to the Advanced Fuels Campaign (AFC) describing the behavior of the concepts, both of which are being considered for inclusion in a lead test assembly scheduled for placement into a commercial reactor in 2022. The initial focus of the HIP is on uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (INL, LANL, and ANL) a comprehensive mulitscale approach to modeling is being used including atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. In this paper, we present simulations of two proposed accident tolerant fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. The simulations investigate the fuel performance response of the proposed ATF systems under Loss of Coolant and Station Blackout conditions using the BISON code. Sensitivity analyses are completed using Sandia National Laboratories’ DAKOTA software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). Early results indicate that each concept has significant advantages as well as areas of concern. Further work is required prior to formulating the proposition report for the Advanced Fuels Campaign.
Preliminary insights into a model for mafic magma fragmentation
Edwards, Matt; Pioli, Laura; Andronico, Daniele; Cristaldi, Antonio; Scollo, Simona
2017-04-01
Fragmentation of mafic magmas remains a poorly understood process despite the common occurrence of low viscosity explosive eruptions. In fact, it has been commonly overlooked based on the assumption that low viscosity magmas have very limited explosivity and low potential to undergo brittle fragmentation. However, it is now known that highly explosive, ash forming eruptions can be relatively frequent at several mafic volcanoes. Three questions arise due to this - What is the specific fragmentation mechanism occuring in these eruptions? What are the primary factors controlling fragmentation efficiency? Can a link between eruption style and fragmentation efficiency be quantified? We addressed these questions by coupling theoretical observations and field analysis of the recent May 2016 eruption at Mount Etna volcano. Within this complex 10-day event three paroxysmal episodes of pulsating basaltic lava jets alternating with small lava flows were recorded from a vent within the Voragine crater. The associated plumes which were produced deposited tephra along narrow axes to the east and south east. Sampling was done on the deposits associated with the first two plumes and the third one. We briefly characterise the May 2016 eruption by assessing plume height, eruption phases, total erupted masses and fallout boundaries and comparing them to previous eruptions. We also analyse the total grainsize distribution (TGSD) of the scoria particles formed in the jets. Conventional methods for obtaining grainsize and total distributions of an eruption are based on mass and provide limited information on fragmentation though. For this reason, the TGSD was assessed by coupling particle analyser data and conventional sieving data to assess both particle size and number of particle distributions with better precision. This allowed for more accurate testing of several existing models describing the shape of the TGSD. Coupled further with observations on eruption dynamics and eruption
Modeling of enterprise information systems implementation: a preliminary investigation
Yusuf, Yahaya Y.; Abthorpe, M. S.; Gunasekaran, Angappa; Al-Dabass, D.; Onuh, Spencer
2001-10-01
The business enterprise has never been in greater need of Agility and the current trend will continue unabated well into the future. It is now recognized that information system is both the foundation and a necessary condition for increased responsiveness. A successful implementation of Enterprise Resource Planning (ERP) can help a company to move towards delivering on its competitive objectives as it enables suppliers to reach out to customers beyond the borders of traditional market defined by geography. The cost of implementation, even when it is successful, could be significant. Bearing in mind the potential strategic benefits, it is important that the implementation project is managed effectively. To this end a project cost model against which to benchmark ongoing project expenditure versus activities completed has been proposed in this paper.
Dynamic density functional theory of solid tumor growth: Preliminary models
Directory of Open Access Journals (Sweden)
Arnaud Chauviere
2012-03-01
Full Text Available Cancer is a disease that can be seen as a complex system whose dynamics and growth result from nonlinear processes coupled across wide ranges of spatio-temporal scales. The current mathematical modeling literature addresses issues at various scales but the development of theoretical methodologies capable of bridging gaps across scales needs further study. We present a new theoretical framework based on Dynamic Density Functional Theory (DDFT extended, for the first time, to the dynamics of living tissues by accounting for cell density correlations, different cell types, phenotypes and cell birth/death processes, in order to provide a biophysically consistent description of processes across the scales. We present an application of this approach to tumor growth.
Preliminary characterization and modeling of SMA-based textile composites
Masuda, Arata; Ni, Qing-Qing; Sone, Akira; Zhang, Run-Xin; Yamamura, Takahiko
2004-07-01
In this paper, we conduct a feasibility study to investigate the future potential of textile composites with shape memory alloys. Two different types of SMA-based textile composites are presented. First, a composite plate with embedded woven SMA layer is fabricated, and the stiffness tuning capability is evaluated by impact vibration tests. The results are not favorable, but may be improved by increasing the volume fraction of SMA, and by controlling the prestrain more accurately during the lamination process. The modeling and analysis methodology for woven SMA-based composites are briefly discussed. Then, the possibility of textile composites with SMA stitching is discussed, that is expected to give the composites multi-functions such as tunable stiffness, shape control and sensing capability, selectively distributed on demand.
Kufner, S. K.; Huepers, A.; Kopf, A.; Wenzel, F.
2011-12-01
, wedge geometry and subduction rate. The porosity values in the subductione zone are calculated by converting interval velocities from seismic sections using an empirical relationship. The dehydration source is calculated using a kinematic reaction model. Laboratory consolidation tests were run to determine the relationship between porosity and permeability. Preliminary results show that the accreted sediment's porosity reduces rapidly near the deformation front and fluids from compaction are predominantly expelled near the trench. At higher temperature and pressure mineral dehydration becomes the major source of fluid production. Different simulation inputs show that the magnitude of total fluid production is a function of estimated taper angle, permeability of the sediment and internal water sources bound in hydrous minerals. Compared to the overriding wedge the underthrust section is significantly overpressured. This observation is supported by higher porosities inferred from seismic velocities. The future study will compare model outputs with measurements from long-term deployed flow meters and in situ pore pressure probes, gravity core data and critical taper theory to obtain best fits in-situ conditions.
Comparison of Hugoniots calculated for aluminum in the framework of three quantum-statistical models
Kadatskiy, Maxim A
2015-01-01
The results of calculations of thermodynamic properties of aluminum under shock compression in the framework of the Thomas--Fermi model, the Thomas--Fermi model with quantum and exchange corrections and the Hartree--Fock--Slater model are presented. The influences of the thermal motion and the interaction of ions are taken into account in the framework of three models: the ideal gas, the one-component plasma and the charged hard spheres. Calculations are performed in the pressure range from 1 to $10^7$ GPa. Calculated Hugoniots are compared with available experimental data.
Comparison of Hugoniots calculated for aluminum in the framework of three quantum-statistical models
Kadatskiy, M. A.; Khishchenko, K. V.
2015-11-01
The results of calculations of thermodynamic properties of aluminum under shock compression in the framework of the Thomas-Fermi model, the Thomas-Fermi model with quantum and exchange corrections and the Hartree-Fock-Slater model are presented. The influences of the thermal motion and the interaction of ions are taken into account in the framework of three models: the ideal gas, the one-component plasma and the charged hard spheres. Calculations are performed in the pressure range from 1 to 107 GPa. Calculated Hugoniots are compared with available experimental data.
Developing ontological model of computational linear algebra - preliminary considerations
Wasielewska, K.; Ganzha, M.; Paprzycki, M.; Lirkov, I.
2013-10-01
The aim of this paper is to propose a method for application of ontologically represented domain knowledge to support Grid users. The work is presented in the context provided by the Agents in Grid system, which aims at development of an agent-semantic infrastructure for efficient resource management in the Grid. Decision support within the system should provide functionality beyond the existing Grid middleware, specifically, help the user to choose optimal algorithm and/or resource to solve a problem from a given domain. The system assists the user in at least two situations. First, for users without in-depth knowledge about the domain, it should help them to select the method and the resource that (together) would best fit the problem to be solved (and match the available resources). Second, if the user explicitly indicates the method and the resource configuration, it should "verify" if her choice is consistent with the expert recommendations (encapsulated in the knowledge base). Furthermore, one of the goals is to simplify the use of the selected resource to execute the job; i.e., provide a user-friendly method of submitting jobs, without required technical knowledge about the Grid middleware. To achieve the mentioned goals, an adaptable method of expert knowledge representation for the decision support system has to be implemented. The selected approach is to utilize ontologies and semantic data processing, supported by multicriterial decision making. As a starting point, an area of computational linear algebra was selected to be modeled, however, the paper presents a general approach that shall be easily extendable to other domains.
Energy Technology Data Exchange (ETDEWEB)
Burlon, A.A.; Girola, S. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, San Martin (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, San Martin (Argentina); Valda, A.A., E-mail: valda@tandar.cnea.gov.ar [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, San Martin (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, San Martin (Argentina); Minsky, D.M.; Kreiner, A.J. [Gerencia de Investigacion y Aplicaciones, Comision Nacional de Energia Atomica, San Martin (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, San Martin (Argentina)] [CONICET, Buenos Aires (Argentina); Sanchez, G. [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, San Martin (Argentina)
2011-12-15
This work reports on the characterisation of a neutron beam shaping assembly (BSA) prototype and on the preliminary modelling of a treatment room for BNCT within the framework of a research programme for the development and construction of an accelerator-based BNCT irradiation facility in Buenos Aires, Argentina. The BSA prototype constructed has been characterised by means of MCNP simulations as well as a set of experimental measurements performed at the Tandar accelerator at the National Atomic Energy Commission of Argentina. - Highlights: Black-Right-Pointing-Pointer Characterisation of a neutron beam shaping assembly for accelerator-based BNCT. Black-Right-Pointing-Pointer Measurements: total and epi-cadmium neutron fluxes and beam homogeneity. Black-Right-Pointing-Pointer Calculations: Monte Carlo simulations with the MCNP code. Black-Right-Pointing-Pointer Measured and calculated figure-of-merit parameters in agreement with those of IAEA. Black-Right-Pointing-Pointer Initial MCNP dose calculations for a treatment room to define future design actions.
Kuss, DJ; Shorter, GW; Van Rooij, AJ; Griffiths, MD; Schoenmakers, T.
2014-01-01
Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (2005), i...
A very simple dynamic soil acidification model for scenario analyses and target load calculations
Posch, M.; Reinds, G.J.
2009-01-01
A very simple dynamic soil acidification model, VSD, is described, which has been developed as the simplest extension of steady-state models for critical load calculations and with an eye on regional applications. The model requires only a minimum set of inputs (compared to more detailed models) and
Online calculators for geomagnetic models at the National Geophysical Data Center
Ford, J. P.; Nair, M.; Maus, S.; McLean, S. J.
2009-12-01
NOAA’s National Geophysical Data Center at Boulder provides online calculators for geomagnetic field models. These models provide current and past values of the geomagnetic field on regional and global spatial scales. These calculators are popular among scientists, engineers and the general public across the world as a resource to compute geomagnetic field elements. We regularly update both the web interfaces and the underlying geomagnetic models. We have four different calculators to compute geomagnetic fields for different user applications. The declination calculators optionally use our World Magnetic Model (WMM) or the International Geomagnetic Reference Field (IGRF) to provide geomagnetic declination as well as its annual rate of change for the chosen location. All seven magnetic field components for a single day or for a range of years from 1900-present can obtained using our Magnetic Field Calculator IGRFWMM. Users can also compute magnetic field values (current and past) over an area using the IGRFGrid calculator. The USHistoric calculator uses a US declination model to compute the declination for the conterminous US from 1750 - present (data permitting). All calculators allow the user to enter the location either as a Zip Code or by specifying the geographic latitude and longitude.
Directory of Open Access Journals (Sweden)
Alhassid Y.
2014-04-01
Full Text Available The shell model Monte Carlo (SMMC method enables calculations in model spaces that are many orders of magnitude larger than those that can be treated by conventional methods, and is particularly suitable for the calculation of level densities in the presence of correlations. We review recent advances and applications of SMMC for the microscopic calculation of level densities. Recent developments include (i a method to calculate accurately the ground-state energy of an odd-mass nucleus, circumventing a sign problem that originates in the projection on an odd number of particles, and (ii a method to calculate directly level densities, which, unlike state densities, do not include the spin degeneracy of the levels. We calculated the level densities of a family of nickel isotopes 59−64Ni and of a heavy deformed rare-earth nucleus 162Dy and found them to be in close agreement with various experimental data sets.
Alhassid, Y; Liu, S; Mukherjee, A; Nakada, H
2014-01-01
The shell model Monte Carlo (SMMC) method enables calculations in model spaces that are many orders of magnitude larger than those that can be treated by conventional methods, and is particularly suitable for the calculation of level densities in the presence of correlations. We review recent advances and applications of SMMC for the microscopic calculation of level densities. Recent developments include (i) a method to calculate accurately the ground-state energy of an odd-mass nucleus, circumventing a sign problem that originates in the projection on an odd number of particles, and (ii) a method to calculate directly level densities, which, unlike state densities, do not include the spin degeneracy of the levels. We calculated the level densities of a family of nickel isotopes $^{59-64}$Ni and of a heavy deformed rare-earth nucleus $^{162}$Dy and found them to be in close agreement with various experimental data sets.
Hierarchical Modeling and Robust Synthesis for the Preliminary Design of Large Scale Complex Systems
Koch, Patrick N.
1997-01-01
Large-scale complex systems are characterized by multiple interacting subsystems and the analysis of multiple disciplines. The design and development of such systems inevitably requires the resolution of multiple conflicting objectives. The size of complex systems, however, prohibits the development of comprehensive system models, and thus these systems must be partitioned into their constituent parts. Because simultaneous solution of individual subsystem models is often not manageable iteration is inevitable and often excessive. In this dissertation these issues are addressed through the development of a method for hierarchical robust preliminary design exploration to facilitate concurrent system and subsystem design exploration, for the concurrent generation of robust system and subsystem specifications for the preliminary design of multi-level, multi-objective, large-scale complex systems. This method is developed through the integration and expansion of current design techniques: Hierarchical partitioning and modeling techniques for partitioning large-scale complex systems into more tractable parts, and allowing integration of subproblems for system synthesis; Statistical experimentation and approximation techniques for increasing both the efficiency and the comprehensiveness of preliminary design exploration; and Noise modeling techniques for implementing robust preliminary design when approximate models are employed. Hierarchical partitioning and modeling techniques including intermediate responses, linking variables, and compatibility constraints are incorporated within a hierarchical compromise decision support problem formulation for synthesizing subproblem solutions for a partitioned system. Experimentation and approximation techniques are employed for concurrent investigations and modeling of partitioned subproblems. A modified composite experiment is introduced for fitting better predictive models across the ranges of the factors, and an approach for
Modeling EEG fractal dimension changes in wake and drowsy states in humans--a preliminary study.
Bojić, Tijana; Vuckovic, Aleksandra; Kalauzi, Aleksandar
2010-01-21
Aim of this preliminary study was to examine and compare topographic distribution of Higuchi's fractal dimension (FD, measure of signal complexity) of EEG signals between states of relaxed wakefulness and drowsiness, as well as their FD differences. The experiments were performed on 10 healthy individuals using a fourteen-channel montage. An explanation is offered on the causes of the detected FD changes. FD values of 60s records belonging to wake (Hori's stage 1) and drowsy (Hori's stages 2-4) states were calculated for each channel and each subject. In 136 out of 140 epochs an increase in FD was obtained. Relationship between signal FD and its relative alpha amplitude was mathematically modeled and we quantitatively demonstrated that the increase in FD was predominantly due to a reduction in alpha activity. The model was generalized to include other EEG oscillations. By averaging FD values for each channel across 10 subjects, four clusters (O2O1; T6P4T5P3; C3F3F4C4F8F7; T4T3) for the wake and two clusters (O2O1P3T6P4T5; C3C4F4F3F8T4T3F7) for the drowsy state were statistically verified. Topographic distribution of FD values in wakefulness showed a lateral symmetry and a partial fronto-occipital gradient. In drowsiness, a reduction in the number of clusters was detected, due to regrouping of channels T3, T4, O1 and O2. Topographic distribution of absolute FD differences revealed largest values at F7, O1 and F3. Reorganization of channel clusters showed that regionalized brain activity, specific for wakefulness, became more global by entering into drowsiness. Since the global increase in FD during wake-to-drowsy transition correlated with the decrease of alpha power, we inferred that increase of EEG complexity may not necessarily be an index of brain activation.
Joris Mulder; Herbert Hoijtink; Christiaan de Leeuw
2012-01-01
This paper discusses a Fortran 90 program referred to as BIEMS (Bayesian inequality and equality constrained model selection) that can be used for calculating Bayes factors of multivariate normal linear models with equality and/or inequality constraints between the model parameters versus a model containing no constraints, which is referred to as the unconstrained model. The prior that is used under the unconstrained model is the conjugate expected-constrained posterior prior and the prior un...
Biologically Inspired Visual Model With Preliminary Cognition and Active Attention Adjustment.
Qiao, Hong; Xi, Xuanyang; Li, Yinlin; Wu, Wei; Li, Fengfu
2015-11-01
Recently, many computational models have been proposed to simulate visual cognition process. For example, the hierarchical Max-Pooling (HMAX) model was proposed according to the hierarchical and bottom-up structure of V1 to V4 in the ventral pathway of primate visual cortex, which could achieve position- and scale-tolerant recognition. In our previous work, we have introduced memory and association into the HMAX model to simulate visual cognition process. In this paper, we improve our theoretical framework by mimicking a more elaborate structure and function of the primate visual cortex. We will mainly focus on the new formation of memory and association in visual processing under different circumstances as well as preliminary cognition and active adjustment in the inferior temporal cortex, which are absent in the HMAX model. The main contributions of this paper are: 1) in the memory and association part, we apply deep convolutional neural networks to extract various episodic features of the objects since people use different features for object recognition. Moreover, to achieve a fast and robust recognition in the retrieval and association process, different types of features are stored in separated clusters and the feature binding of the same object is stimulated in a loop discharge manner and 2) in the preliminary cognition and active adjustment part, we introduce preliminary cognition to classify different types of objects since distinct neural circuits in a human brain are used for identification of various types of objects. Furthermore, active cognition adjustment of occlusion and orientation is implemented to the model to mimic the top-down effect in human cognition process. Finally, our model is evaluated on two face databases CAS-PEAL-R1 and AR. The results demonstrate that our model exhibits its efficiency on visual recognition process with much lower memory storage requirement and a better performance compared with the traditional purely computational
Improvements on Calculation Model of Theoretical Combustion Temperature in a Blast Furnace
Institute of Scientific and Technical Information of China (English)
WU Sheng-li; LIU Cheng-song; FU Chang-liang; XU Jian; KOU Ming-yin
2011-01-01
On the basis of the existing originally modified calculation models of theoretical combustion temperature（TCT）,some factors,such as the combustion ratio of pulverized coal injection（PCI）,the decomposition heat of PCI and the heat consumption of SiO2 in ash reduced in high temperature environment,were amended and improved to put forward a more comprehensive model for calculating TCT.The influences of each improvement on TCT were studied and the results were analyzed compared with those of traditional model and originally modified model,which showed that the present model could reflect the thermal state of a hearth more effectively.
Environmental Barrier Coating (EBC) Durability Modeling; An Overview and Preliminary Analysis
Abdul-Aziz, A.; Bhatt, R. T.; Grady, J. E.; Zhu, D.
2012-01-01
A study outlining a fracture mechanics based model that is being developed to investigate crack growth and spallation of environmental barrier coating (EBC) under thermal cycling conditions is presented. A description of the current plan and a model to estimate thermal residual stresses in the coating and preliminary fracture mechanics concepts for studying crack growth in the coating are also discussed. A road map for modeling life and durability of the EBC and the results of FEA model(s) developed for predicting thermal residual stresses and the cracking behavior of the coating are generated and described. Further initial assessment and preliminary results showed that developing a comprehensive EBC life prediction model incorporating EBC cracking, degradation and spalling mechanism under stress and temperature gradients typically seen in turbine components is difficult. This is basically due to mismatch in thermal expansion difference between sub-layers of EBC as well as between EBC and substrate, diffusion of moisture and oxygen though the coating, and densification of the coating during operating conditions as well as due to foreign object damage, the EBC can also crack and spall from the substrate causing oxidation and recession and reducing the design life of the EBC coated substrate.
Energy Technology Data Exchange (ETDEWEB)
Perry, K.E. Jr.; Buescher, B.J.; Anderson, D.; Epstein, J.S. [Idaho National Engineering Lab., Idaho Falls, ID (United States)
1995-09-01
An important aspect of determining the suitability of Yucca Mountain as a possible nuclear waste repository requires understanding the mechanical behavior of jointed rock-masses. To this end we have studied the frictional sliding between simulated rock joints in the laboratory using the technique of phase shifting moire interferometry. The models were made from stacks of Lexan plates and contained a central hole to induce slip between the plates when the models were loaded in compression. These preliminary results confirm the feasibility of the approach and show a clear evolution of slip as function of load.
Model operator approach to the Lamb shift calculations in relativistic many-electron atoms
Shabaev, V M; Yerokhin, V A
2013-01-01
A model operator approach to calculations of the QED corrections to energy levels in relativistic many-electron atomic systems is developed. The model Lamb shift operator is represented by a sum of local and nonlocal potentials which are defined using the results of ab initio calculations of the diagonal and nondiagonal matrix elements of the one-loop QED operator with H-like wave functions. The model operator can be easily included in any calculations based on the Dirac-Coulomb-Breit Hamiltonian. Efficiency of the method is demonstrated by comparison of the model QED operator results for the Lamb shifts in many-electron atoms and ions with exact QED calculations.
Fast and accurate calculation of dilute quantum gas using Uehling-Uhlenbeck model equation
Yano, Ryosuke
2017-02-01
The Uehling-Uhlenbeck (U-U) model equation is studied for the fast and accurate calculation of a dilute quantum gas. In particular, the direct simulation Monte Carlo (DSMC) method is used to solve the U-U model equation. DSMC analysis based on the U-U model equation is expected to enable the thermalization to be accurately obtained using a small number of sample particles and the dilute quantum gas dynamics to be calculated in a practical time. Finally, the applicability of DSMC analysis based on the U-U model equation to the fast and accurate calculation of a dilute quantum gas is confirmed by calculating the viscosity coefficient of a Bose gas on the basis of the Green-Kubo expression and the shock layer of a dilute Bose gas around a cylinder.
Hot DA white dwarf model atmosphere calculations: Including improved Ni PI cross sections
Preval, S P; Badnell, N R; Hubeny, I; Holberg, J B
2016-01-01
To calculate realistic models of objects with Ni in their atmospheres, accurate atomic data for the relevant ionization stages needs to be included in model atmosphere calculations. In the context of white dwarf stars, we investigate the effect of changing the Ni {\\sc iv}-{\\sc vi} bound-bound and bound-free atomic data has on model atmosphere calculations. Models including PICS calculated with {\\sc autostructure} show significant flux attenuation of up to $\\sim 80$\\% shortward of 180\\AA\\, in the EUV region compared to a model using hydrogenic PICS. Comparatively, models including a larger set of Ni transitions left the EUV, UV, and optical continua unaffected. We use models calculated with permutations of this atomic data to test for potential changes to measured metal abundances of the hot DA white dwarf G191-B2B. Models including {\\sc autostructure} PICS were found to change the abundances of N and O by as much as $\\sim 22$\\% compared to models using hydrogenic PICS, but heavier species were relatively unaf...
National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...
DEFF Research Database (Denmark)
Yuan, Hao; You, Zhenjiang; Shapiro, Alexander
2013-01-01
Colloidal-suspension flow in porous media is modelled simultaneously by the large scale population balance equations and by the microscale network model. The phenomenological parameter of the correlation length in the population balance model is determined from the network modelling. It is found ...... out that the correlation length in the population balance model depends on the particle size. This dependency calculated by two-dimensional network has the same tendency as that obtained from the laboratory tests in engineered porous media....
Model-Based Radar Power Calculations for Ultra-Wideband (UWB) Synthetic Aperture Radar (SAR)
2013-06-01
performance in complex scenarios. Among these scenarios are ground penetrating radar and forward-looking radar for landmine and improvised explosive...Model-Based Radar Power Calculations for Ultra-Wideband (UWB) Synthetic Aperture Radar (SAR) by Traian Dogaru ARL-TN-0548 June 2013...2013 Model-Based Radar Power Calculations for Ultra-Wideband (UWB) Synthetic Aperture Radar (SAR) Traian Dogaru Sensors and Electron
Study on comparison of different methods to calculating sensitivity index of Jensen model
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Real coded Accelerating Genetic Algorithm (RAGA), Chaos Algorithm (CA) were used to solve the sensitivity index of Jensen model which is one of models of crop water production function. After comparing with the outcome of Least Square Regression (LSR), the result showed that RAGA not only had high accuracy and more effective, but also saved calculating time. The authors provides new effective methods for calculating index of crop water production function.
Energy Technology Data Exchange (ETDEWEB)
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
Analytical approach to calculation of response spectra from seismological models of ground motion
Safak, Erdal
1988-01-01
An analytical approach to calculate response spectra from seismological models of ground motion is presented. Seismological models have three major advantages over empirical models: (1) they help in an understanding of the physics of earthquake mechanisms, (2) they can be used to predict ground motions for future earthquakes and (3) they can be extrapolated to cases where there are no data available. As shown with this study, these models also present a convenient form for the calculation of response spectra, by using the methods of random vibration theory, for a given magnitude and site conditions. The first part of the paper reviews the past models for ground motion description, and introduces the available seismological models. Then, the random vibration equations for the spectral response are presented. The nonstationarity, spectral bandwidth and the correlation of the peaks are considered in the calculation of the peak response.
Zhang, Zhen; Xia, Changliang; Yan, Yan; Geng, Qiang; Shi, Tingna
2017-08-01
Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff's law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell's equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.
Calculation Model for Current-voltage Relation of Silicon Quantum-dots-based Nano-memory
Institute of Scientific and Technical Information of China (English)
YANG Hong-guan; DAI Da-kang; YU Biao; SHANG Lin-lin; GUO You-hong
2007-01-01
Based on the capacitive coupling formalism, an analytic model for calculating the drain currents of the quantum-dots floating-gate memory cell is proposed. Using this model, one can calculate numerically the drain currents of linear, saturation and subthreshold regions of the device with/without charges stored on the floating dots. The read operation process of an n-channel Si quantum-dots floating-gate nano-memory cell is discussed after calculating the drain currents versus the drain to source voltages and control gate voltages in both high and low threshold states respectively.
A Model for the Calculation of Velocity Reduction Behind A Plane Fishing Net
Institute of Scientific and Technical Information of China (English)
GUI Fu-kun; LI Yu-cheng; ZHAO Yun-peng; DONG Guo-hai
2006-01-01
A model for the calculation of velocity reduction behind a fishing net is proposed in this paper. Comparisons are made between the calculated results and experimental data. It is shown that by the application of the effective adjacent area coefficient of fluid flowing around a solid structure to the fishing net, the calculated results agree well with the experimental data. The model proposed in this paper can also be applied to the analysis of the velocity reduction within a fishing cage and can be introduced into the numerical simulation of the hydrodynamic behavior of fishing cages for the improvement of computational accuracy.
Calculation of delayed-neutron energy spectra in a QRPA-Hauser-Feshbach model
Energy Technology Data Exchange (ETDEWEB)
Kawano, Toshihiko [Los Alamos National Laboratory; Moller, Peter [Los Alamos National Laboratory; Wilson, William B [Los Alamos National Laboratory
2008-01-01
Theoretical {beta}-delayed-neutron spectra are calculated based on the Quasiparticle Random-Phase Approximation (QRPA) and the Hauser-Feshbach statistical model. Neutron emissions from an excited daughter nucleus after {beta} decay to the granddaughter residual are more accurately calculated than in previous evaluations, including all the microscopic nuclear structure information, such as a Gamow-Teller strength distribution and discrete states in the granddaughter. The calculated delayed-neutron spectra agree reasonably well with those evaluations in the ENDF decay library, which are based on experimental data. The model was adopted to generate the delayed-neutron spectra for all 271 precursors.
Energy Technology Data Exchange (ETDEWEB)
Scheel, Joerg; Dib, Ramzi [Fachhochschule Giessen-Friedberg, Friedberg (Germany); Sassmannshausen, Achim [DB Energie GmbH, Frankfurt (Main) (Germany). Arbeitsgebiet Bahnstromleitungen Energieerzeugungs- und Uebertragungssysteme; Riedl, Markus [Eon Netz GmbH, Bayreuth (Germany). Systemtechnik Leitungen
2010-12-13
Increasingly, high-temperature cables are used in high-voltage grids. Beyond a given temperature level, their slack span cannot be calculated accurately by conventional simple linear methods. The contribution investigates the behaviour of composite cables at high operating temperatures and its influence on the slack span and presents a more accurate, bilingual calculation method. (orig.)
Comparison of results of experimental research with numerical calculations of a model one-sided seal
Directory of Open Access Journals (Sweden)
Joachimiak Damian
2015-06-01
Full Text Available Paper presents the results of experimental and numerical research of a model segment of a labyrinth seal for a different wear level. The analysis covers the extent of leakage and distribution of static pressure in the seal chambers and the planes upstream and downstream of the segment. The measurement data have been compared with the results of numerical calculations obtained using commercial software. Based on the flow conditions occurring in the area subjected to calculations, the size of the mesh defined by parameter y+ has been analyzed and the selection of the turbulence model has been described. The numerical calculations were based on the measurable thermodynamic parameters in the seal segments of steam turbines. The work contains a comparison of the mass flow and distribution of static pressure in the seal chambers obtained during the measurement and calculated numerically in a model segment of the seal of different level of wear.
Energy Technology Data Exchange (ETDEWEB)
Nguyen, Son (ed.) [Canadian Nuclear Safety Commission (Canada); Lanru Jing (ed.) [Royal Institute of Technology, Stockholm (Sweden); Boergesson, Lennart [Clay Technology AB, Lund (Sweden); Chijimatzu, Masakazu [Hazama Corporation (Japan); Jussila, Petri [Helsinki Univ. of Technology, Helsinki (Finland); Rutqvist, Jonny [Lawrence Berkeley National Laboratory CA (United States)
2007-02-15
The DECOVALEX-THMC project is an ongoing international co-operative project that was stared in 2004 to support the development of mathematical models of coupled Thermal (T), Hydrological (H), Mechanical (M) and Chemical (C) processes in geological media for siting potential nuclear fuel waste repositories. The general objective is to characterise and evaluate the coupled THMC processes in the near field and far field of a geological repository and to assess their impact on performance assessment: - during the three phases of repository development: excavation phase, operation phase and post-closure phase; - for three different rocks types: crystalline, argillaceous and tuff; - with specific focus on the issues of: Excavation Damaged Zone (EDZ), permanent property changes of rock masses, and glaciation and permafrost phenomena. The project involves a large number of research teams supported by radioactive waste management agencies or governmental regulatory bodies in Canada, China, Finland, France, Germany, Japan, Sweden and USA, who conducted advanced studies and numerical modelling of coupled THMC processes under five tasks. This report presents the definition of the first phase, Task A-1, of the Task A of the project. The task is a working example of how interaction between THMC modelling and SA analysis could be performed. Starting with the technical definition of the Task A, the report presents the results of preliminary THM calculations with a purpose of an initial appreciation of the phenomena and material properties that must be better understood in subsequent phases. Many simplifications and assumptions were introduced and the results should be considered under these assumptions. Based on the evaluation of the multiple teams' results, a few points of concern were identified that may guide the successive phases of Task A studies: 1. The predicted maximum total stress in the MX-80 bentonite could slightly exceed the 15 MPa design pressure for the
Calculation of energy spectrum of $^{12}$C isotope with modified Yukawa potential by cluster models
Indian Academy of Sciences (India)
MOHAMMAD REZA SHOJAE; NAFISEH ROSHAN BAKHT
2016-10-01
In this paper, we have calculated the energy spectrum of 12C isotope in two-cluster models, $3\\alpha$ cluster model and $^8$Be + $\\alpha$ cluster model. We use the modified Yukawa potential for interaction between theclusters and solve the Schrödinger equation using Nikiforov–Uvarov method to calculate the energy spectrum. Then, we increase the accuracy by adding spin-orbit coupling and tensor force and solve them by perturbationtheory in both models. Finally, the calculated results for both models are compared with each other and with the experimental data. The results show that the isotope $^{12}$C should be considered as a three-$\\alpha$ cluster and themodified Yukawa potential is adaptable for cluster interactions.
Multi-Scale Thermohydrologic Model Sensitivity-Study Calculations in Support of the SSPA
Energy Technology Data Exchange (ETDEWEB)
Glascoe, L G; Buscheck, T A; Loosmore, G A; Sun, Y
2001-12-20
The purpose of this calculation report is to document the thermohydrologic (TH) model calculations performed for the Supplemental Science and Performance Analysis (SSPA), Volume 1, Section 5 and Volume 2 (BSC 2001d [DIRS 155950], BSC 2001e [DIRS 154659]). The calculations are documented here in accordance with AP-3.12Q REV0 ICN4 [DIRS 154418]. The Technical Working Plan (Twp) for this document is TWP-NGRM-MD-000015 Real. These TH calculations were primarily conducted using three model types: (1) the Multiscale Thermohydrologic (MSTH) model, (2) the line-averaged-heat-source, drift-scale thermohydrologic (LDTH) model, and (3) the discrete-heat-source, drift-scale thermal (DDT) model. These TH-model calculations were conducted to improve the implementation of the scientific conceptual model, quantify previously unquantified uncertainties, and evaluate how a lower-temperature operating mode (LTOM) would affect the in-drift TH environment. Simulations for the higher-temperature operating mode (HTOM), which is similar to the base case analyzed for the Total System Performance Assessment for the Site Recommendation (TSPA-SR) (CRWMS M&O 2000j [DIRS 153246]), were also conducted for comparison with the LTOM. This Calculation Report describes (1) the improvements to the MSTH model that were implemented to reduce model uncertainty and to facilitate model validation, and (2) the sensitivity analyses conducted to better understand the influence of parameter and process uncertainty. The METHOD Section (Section 2) describes the improvements to the MSTH-model methodology and submodels. The ASSUMPTIONS Section (Section 3) lists the assumptions made (e.g., boundaries, material properties) for this methodology. The USE OF SOFTWARE Section (Section 4) lists the software, routines and macros used for the MSTH model and submodels supporting the SSPA. The CALCULATION Section (Section 5) lists the data used in the model and the manner in which the MSTH model is prepared and executed. And
Advanced model for the calculation of meshing forces in spur gear planetary transmissions
Iglesias Santamaría, Miguel; Fernández del Rincón, Alfonso; Juan de Luna, Ana Magdalena de; Díez Ibarbia, Alberto; García Fernández, Pablo; Viadero Rueda, Fernando
2015-01-01
This paper presents a planar spur gear planetary transmission model, describing in great detail aspects such as the geometric definition of geometric overlaps and the contact forces calculation, thus facilitating the reproducibility of results by fellow researchers. The planetary model is based on a mesh model already used by the authors in the study of external gear ordinary transmissions. The model has been improved and extended to allow for the internal meshing simulation, taking into cons...
Preliminary assessment of the behavioral activation model in Japanese undergraduate students.
Takagaki, Koki; Okajima, Isa; Kunisato, Yoshihiko; Nakajima, Shun; Kanai, Yoshihiro; Ishikawa, Shin-Ichi; Sakano, Yuji
2013-02-01
Many studies have reported that behavioral activation is an effective intervention for depression. The behavioral activation model is based on several formulations. For example, depressive mood leads to avoidant behaviors, avoidance negatively affects social contacts, decreased socialization lessens opportunities for positive reinforcement, and a decrease in positive reinforcement results in more depressive mood. The purpose of this study was to examine relationships among avoidant behavior, social contact, frequency of positive reinforcement, and depressive mood by using structural equation modeling to assess support for aspects of this behavioral activation model. Participants were 630 Japanese undergraduate students and vocational school students. Results provided preliminary support for the model. Treating both avoidance and activating behavior might contribute to decreased impairment.
Institute of Scientific and Technical Information of China (English)
曹国辉; 胡佳星; 张锴
2016-01-01
The calculation model for the relaxation loss of concrete mentioned in the Code for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts(JTG D62—2004) wasmodified according to experimental data. Time-varying relaxation loss was considered in the new model. Moreover, prestressed reinforcement with varying lengths (caused by the shrinkage and creep of concrete) might influence the final values and the time-varying function of the forecast relaxation loss. Hence, the effects of concrete shrinkage and creep were considered when calculating prestress loss, which reflected the coupling relation between these effects and relaxation loss in concrete. Hence, the forecast relaxation loss of prestressed reinforcement under the effects of different initial stress levels at any time point can be calculated using the modified model. To simplify the calculation, the integral expression of the model can be changed into an algebraic equation. The accuracy of the result is related to the division of the periods within the ending time of deriving the final value of the relaxation loss of prestressed reinforcement. When the time division is reasonable, result accuracy is high. The modified model works excellently according to the comparison of the test results. The calculation result of the modified model mainly reflects the prestress loss values of prestressed reinforcement at each time point, which confirms that adopting the finding in practical applications is reasonable.
Heterosexual male perpetrators of childhood sexual abuse: a preliminary neuropsychiatric model.
Cohen, Lisa J; Nikiforov, Konstantin; Gans, Sniezyna; Poznansky, Olga; McGeoch, Pamela; Weaver, Carrie; King, Enid Gertmanian; Cullen, Ken; Galynker, Igor
2002-01-01
This paper presents data from a series of preliminary neuropsychiatric studies, including neuropsychological, personality, sexual history, plethysmographic and neuroimaging investigations, on a sample of 22 male, heterosexual, nonexclusive pedophiles and 24 demographically similar healthy controls. A psychobiological model of pedophilia is proposed, positing that early childhood sexual abuse leads to neurodevelopmental abnormalities in the temporal regions mediating sexual arousal and erotic discrimination and the frontal regions mediating the cognitive aspects of sexual desire and behavioral inhibition. In this way, pedophiles develop deviant pedophilic arousal. Subsequently, if there is comorbid personality pathology, specifically sociopathy and cognitive distortions, there will be failure to inhibit pedophilic behavior.
A dispersion model approach to the preliminary design of adsorber beds for trace contaminants
Madey, R.; Czayka, M.; Forsythe, R.; Povlis, J.; Yin, K.
1976-01-01
It is shown that a dispersion model for the transport of a gas through a porous medium can be useful in the preliminary design of adsorber beds for the control of trace contaminants. The transmission function is considered, taking into account the transmission of 102-ppm acetaldehyde in helium flowing at various flow rates through an absorber bed. The experiments were conducted at a temperature of 25.0 C. Attention is given to a representation of the experimental breakthrough curve, the volume adsorption capacity, temperature studies, and correlations.
A musculoskeletal lumbar and thoracic model for calculation of joint kinetics in the spine
Energy Technology Data Exchange (ETDEWEB)
Kim, Yong Cheol; Ta, Duc manh; Koo, Seung Bum [Chung-Ang University, Seoul (Korea, Republic of); Jung Moon Ki [AnyBody Technology A/S, Aalborg (Denmark)
2016-06-15
The objective of this study was to develop a musculoskeletal spine model that allows relative movements in the thoracic spine for calculation of intra-discal forces in the lumbar and thoracic spine. The thoracic part of the spine model was composed of vertebrae and ribs connected with mechanical joints similar to anatomical joints. Three different muscle groups around the thoracic spine were inserted, along with eight muscle groups around the lumbar spine in the original model from AnyBody. The model was tested using joint kinematics data obtained from two normal subjects during spine flexion and extension, axial rotation and lateral bending motions beginning from a standing posture. Intra-discal forces between spine segments were calculated in a musculoskeletal simulation. The force at the L4-L5 joint was chosen to validate the model's prediction against the lumbar model in the original AnyBody model, which was previously validated against clinical data.
SAMPLE AOR CALCULATION USING ANSYS AXISYMMETRIC PARAMETRIC MODEL FOR TANK SST-A
Energy Technology Data Exchange (ETDEWEB)
JULYK, L.J.; MACKEY, T.C.
2003-06-19
This document documents the ANSYS axisymmetric parametric model for single-shell tank A and provides sample calculation for analysis-of-record mechanical load conditions. The purpose of this calculation is to develop a parametric model for single shell tank (SST) A, and provide a sample analysis of SST-A tank based on analysis of record (AOR) loads. The SST-A model is based on buyer-supplied as-built drawings and information for the AOR for SSTs, encompassing the existing tank load conditions, and evaluates stresses and deformations throughout the tank and surrounding soil mass.
SAMPLE AOR CALCULATION USING ANSYS AXISYMMETRIC PARAMETRIC MODEL FOR TANK SST-SX
Energy Technology Data Exchange (ETDEWEB)
JULYK, L.J.; MACKEY, T.C.
2003-06-19
This document documents the ANSYS axisymmetric parametric model for single-shell tank SX and provides sample calculation for analysis-of-record mechanical load conditions. The purpose of this calculation is to develop a parametric model for single shell tank (SST) SX, and provide a sample analysis of the SST-SX tank based on analysis of record (AOR) loads. The SST-SX model is based on buyer-supplied as-built drawings and information for the AOR for SSTs, encompassing the existing tank load conditions, and evaluates stresses and deformations throughout the tank and surrounding soil mass.
SAMPLE AOR CALCULATION USING ANSYS AXISYMMETRIC PARAMETRIC MODEL FOR TANK SST-S
Energy Technology Data Exchange (ETDEWEB)
JULYK, L.J.; MACKEY, T.C.
2003-06-19
This document documents the ANSYS axisymmetric parametric model for single-shell tank S and provides sample calculation for analysis-of-record mechanical load conditions. The purpose of this calculation is to develop a parametric model for single shell tank (SST) S, and provide a sample analysis of SST-S tank based on analysis of record (AOR) loads. The SST-S model is based on buyer-supplied as-built drawings and information for the AOR for SSTs, encompassing the existing tank load conditions, and evaluates stresses and deformations throughout the tank and surrounding soil mass.
Ferraro, Vittorio; Marinelli, Valerio; Mele, Marilena
2013-04-01
It is known that the best predictions of sky luminances are obtainable by the CIE 15 standard skies model, but the predictions by this model need knowledge of the measured luminance distributions themselves, since a criterion for selecting the type of sky starting from the irradiance values has not found until now. The authors propose a new simple method of applying the CIE model, based on the use of the sky index Si. A comparison between calculated luminance data and data measured in Arcavacata of Rende (Italy), Lyon (France) and Pamplona (Spain) show a good performance of this method in comparison with other methods of calculation of luminance existing in the literature.
Power Loss Calculation and Thermal Modelling for a Three Phase Inverter Drive System
Directory of Open Access Journals (Sweden)
Z. Zhou
2005-12-01
Full Text Available Power losses calculation and thermal modelling for a three-phase inverter power system is presented in this paper. Aiming a long real time thermal simulation, an accurate average power losses calculation based on PWM reconstruction technique is proposed. For carrying out the thermal simulation, a compact thermal model for a three-phase inverter power module is built. The thermal interference of adjacent heat sources is analysed using 3D thermal simulation. The proposed model can provide accurate power losses with a large simulation time-step and suitable for a long real time thermal simulation for a three phase inverter drive system for hybrid vehicle applications.
Mathematical Models For Calculating The Value Of Dynamic Viscosity Of A Liquid
Directory of Open Access Journals (Sweden)
Ślęzak M.
2015-06-01
Full Text Available The objective of this article is to review models for calculating the value of liquid dynamic viscosity. Issues of viscosity and rheological properties of liquid ferrous solutions are important from the perspective of modelling, along with the control of actual production processes related to the manufacturing of metals, including iron and steel. Conducted analysis within literature indicates that there are many theoretical considerations concerning the effect of viscosity of liquid metals solutions. The vast majority of models constitute a group of theoretical or semi-empirical equations, where thermodynamic parameters of solutions, or some parameters determined by experimental methods, are used for calculations of the dynamic viscosity coefficient.
A Direct Calculation of Critical Exponents of Two-Dimensional Anisotropic Ising Model
Institute of Scientific and Technical Information of China (English)
XIONG Gang; WANG Xiang-Rong
2006-01-01
Using an exact solution of the one-dimensional quantum transverse-field Ising model, we calculate the critical exponents of the two-dimensional anisotropic classicalIsing model (IM). We verify that the exponents are the same as those of isotropic classical IM. Our approach provides an alternative means of obtaining and verifying these well-known results.
vanVlimmeren, BAC; Fraaije, JGEM
1996-01-01
We present a simple method for the numerical calculation of the noise distribution in multicomponent functional Langevin models. The topic is of considerable importance, in view of the increased interest in the application of mesoscopic dynamics simulation models to phase separation of complex
Corresponding-States and Parachor Models for the Calculation of Interfacial Tensions
DEFF Research Database (Denmark)
Zuo, You-Xiang; Stenby, Erling Halfdan
1997-01-01
-states model. The two models were tested on 86 pure substances, more than 30 binary and multicomponent mixtures, 11 naphtha reformate cuts, 6 petroleum cuts and 2 North Sea oil mixtures. The calculated results were found to be in good agreement with experimental data.Keywords: corresponding-states, parachor...
Benchmark calculation of no-core Monte Carlo shell model in light nuclei
Abe, T; Otsuka, T; Shimizu, N; Utsuno, Y; Vary, J P; 10.1063/1.3584062
2011-01-01
The Monte Carlo shell model is firstly applied to the calculation of the no-core shell model in light nuclei. The results are compared with those of the full configuration interaction. The agreements between them are within a few % at most.
Development of a risk-based mine closure cost calculation model
CSIR Research Space (South Africa)
Du Plessis, A
2006-06-01
Full Text Available The study summarised in this paper focused on expanding existing South African mine closure cost calculation models to provide a new model that incorporates risks, which could have an effect on the closure costs during the life cycle of the mine...
Considerations on the Mathematical model for Calculating the Single-phase Grounding
Directory of Open Access Journals (Sweden)
TATAI Ildiko
2013-05-01
Full Text Available In this paper are presented the results obtained using a mathematical model, conceived in order to analyze the effects of grounding faults that occur in a medium voltage network. Measurements were made on a real electric network. Calculated results using the mathematical model are compared with the actual measurements.
Jensen, L; van Duijnen, PT; Snijders, JG
2003-01-01
A discrete solvent reaction field model for calculating frequency-dependent molecular linear response properties of molecules in solution is presented. The model combines a time-dependent density functional theory (QM) description of the solute molecule with a classical (MM) description of the discr
The problem of margin calculation and its reduction via the p-median problem model
Goldengorin, B.; Krushynskyi, D.; Kuzmenko, V.; Mastorakis, NE; Demiralp, M; Mladenov,; Bojkovic, Z
2009-01-01
The paper deals with a model for calculation of the regulatory margin on brokerage accounts. The model is based on the p-Median problem (PMP) that is known to be NP-hard. We use a pseudo-Boolean representation of the PMP and propose several problem size reduction and preprocessing techniques. Our co
Diameter structure modeling and the calculation of plantation volume of black poplar clones
Directory of Open Access Journals (Sweden)
Andrašev Siniša
2004-01-01
Full Text Available A method of diameter structure modeling was applied in the calculation of plantation (stand volume of two black poplar clones in the section Aigeiros (Duby: 618 (Lux and S1-8. Diameter structure modeling by Weibull function makes it possible to calculate the plantation volume by volume line. Based on the comparison of the proposed method with the existing methods, the obtained error of plantation volume was less than 2%. Diameter structure modeling and the calculation of plantation volume by diameter structure model, by the regularity of diameter distribution, enables a better analysis of the production level and assortment structure and it can be used in the construction of yield and increment tables.
Microscopic interacting boson model calculations for even–even 128−138Ce nuclei
Indian Academy of Sciences (India)
Nurettin Turkan; Ismail Maras
2007-05-01
In this study, we determined the most appropriate Hamiltonian that is needed for the present calculations of energy levels and (2) values of 128−138Ce nuclei which have a mass around ≅ 130 using the interacting boson model (IBM). Using the best-ﬁtted values of parameters in the Hamiltonian of the IBM-2, we have calculated energy levels and (2) values for a number of transitions in 128,130,132,134,136,138Ce. The results were compared with the previous experimental and theoretical (PTSM model) data and it was observed that they are in good agreement. Also some predictions of this model have better accuracy than those of PTSM model. It has turned out that the interacting boson approximation (IBA) is fairly reliable for calculating spectra in the entire set of 128,130,132,134,136,138Ce isotopes and the quality of the ﬁts presented in this paper is acceptable.
DEVELOPMENT OF CALCULATING MODEL APPLICABLE FOR CYLINDER WALL DYNAMIC HEAT TRANSFER
Institute of Scientific and Technical Information of China (English)
ZHONG Minjun; SHI Tielin
2007-01-01
In the calculation of submarine air conditioning load of the early stage, the obtained heat is regarded as cooling load. The confusion of the two words causing the cooling load figured out is abnormally high, and the change of air conditioning cooling load can not be indicated. In accordance with submarine structure and heat transfer characteristics of its inner components, Laplace transformation to heat conduction differential equation of cylinder wall is carried out. The dynamic calculation of submarine conditioning load based on this model is also conducted, and the results of calculation are compared with those of static cooling load calculation. It is concluded that the dynamic cooling load calculation methods can illustrate the change of submarine air conditioning cooling load more accurate than the static one.
A model for calculating heat transfer coefficient concerning ethanol-water mixtures condensation
Wang, J. S.; Yan, J. J.; Hu, S. H.; Yang, Y. S.
2010-03-01
The attempt of the author in this research is made to calculate a heat transfer coefficient (HTC) by combining the filmwise theory with the dropwise notion for ethanol-water mixtures condensation. A new model, including ethanol concentration, vapor pressure and velocity, is developed by introducing a characteristic coefficient to combine the two mentioned-above theories. Under different concentration, pressure and velocity, the calculation is in comparison with experiment. It turns out that the calculation value is in good agreement with the experimental result; the maximal error is within ±30.1%. In addition, the model is applied to calculate related experiment in other literature and the values obtained agree well with results in reference.
Institute of Scientific and Technical Information of China (English)
ZHANG Zhi-jie; LIU Yu-hua; L(U) Zhong-yuan; LI Ze-sheng
2009-01-01
The rotational isomeric state(RIS) model was constructed for poly(vinylidene chloride)(PVDC) based on quantum chemistry calculations. The statistical weighted parameters were obtained from RIS representations and ab initio energies of conformers for model molecules 2,2,4,4-tetrachloropentane(TCP) and 2,2,4,4,6, 6-hexachlorohep-tane(HCH). By employing the RIS method, the characteristic ratio C∞ was calculated for PVDC. The calculated cha-racteristic ratio for PVDC is in good agreement with experiment result. Additionally, we studied the influence of the statistical weighted parameters on C∞ by calculating δC∞/δlnw. According to the values of δC∞/δlnw, the effects of second-order Cl-CH2 pentane type interaction and Cl-Cl long range interaction on C∞ were found to be important. In contrast, first-order interaction is unimportant.
Kaminski, George A.; Ponomarev, Sergei Y.; Liu, Aibing B.
2009-01-01
We are presenting POSSIM (POlarizable Simulations with Second order Interaction Model) – a software package and a set of parameters designed for molecular simulations. The key feature of POSSIM is that the electrostatic polarization is taken into account using a previously introduced fast formalism. This permits cutting computational cost of using the explicit polarization by about an order of magnitude. In this article, parameters for water, methane, ethane, propane, butane, methanol and NMA are introduced. These molecules are viewed as model systems for protein simulations. We have achieved our goal of ca. 0.5 kcal/mol accuracy for gas-phase dimerization energies and no more than 2% deviations in liquid state heats of vaporization and densities. Moreover, free energies of hydration of the polarizable methane, ethane and methanol have been calculated using the statistical perturbation theory. These calculations are a model for calculating protein pKa shifts and ligand binding affinities. The free energies of hydration were found to be 2.12 kcal/mol, 1.80 kcal/mol and −4.95 kcal/mol for methane, ethane and methanol, respectively. The experimentally determined literature values are 1.91 kcal/mol, 1.83 kcal/mol and −5.11 kcal/mol. The POSSIM average error in these absolute free energies of hydration is only about 0.13 kcal/mol. Using the statistical perturbation theory with polarizable force fields is not widespread, and we believe that this work opens road to further development of the POSSIM force field and its applications for obtaining accurate energies in protein-related computer modeling. PMID:20209038
Directory of Open Access Journals (Sweden)
Joris Mulder
2012-01-01
Full Text Available This paper discusses a Fortran 90 program referred to asBIEMS (Bayesian inequality and equality constrained model selection that can be used for calculating Bayes factors of multivariate normal linear models with equality and/or inequality constraints betweenthe model parameters versus a model containing no constraints, which is referred to as the unconstrained model. The prior that is used under the unconstrained model is the conjugate expected-constrained posterior prior and the prior under the constrained model is proportional to the unconstrained prior truncated in the constrained space. This results in Bayes factors that appropriately balance between model t and complexity for a broad class of constrained models. When the set of equality and/or inequality constraints in the model represents a hypothesis that applied researchers have in, for instance, (MAN(COVA, (multivariate regression, or repeated measurements, the obtained Bayes factor can be used to determine how much evidence is provided by the data in favor of the hypothesis in comparison to the unconstrained model. If several hypotheses are underinvestigation, the Bayes factors between the constrained models can be calculated using the obtained Bayes factors from BIEMS. Furthermore, posterior model probabilities of constrained models are provided which allows the user to compare the models directlywith each other.
Theoretical Calculation of Rotational Bands of 179Pt in the Particle-Triaxial-Rotor Model
Institute of Scientific and Technical Information of China (English)
CHEN Guo-Jie; SONG Hui-Chao; LIU Yu-Xin
2005-01-01
Theoretical calculations have been performed for nucleus 179Pt in the particle-triaxial-rotor model with variable moment of inertia. The obtained energy spectrum agrees with the experimental data quite well. The calculated results indicate that the bands 1/2- and 7/2+ are triaxial deformation bands and originate mainly from the v[521]1/2- and v[633]7/2+ configurations respectively.
Calculation of Energy Levels of Nucleus 127I in the Particle-Triaxial-Rotor Model
Institute of Scientific and Technical Information of China (English)
SONG Hui-Chao; LIU Yu-Xin; ZHANG Yu-Hu
2004-01-01
@@ Theoretical calculations have been performed for nucleus 127 I in the framework of the particle-triaxial-rotor model.The calculated results indicate that both the 5+2 and 7+2 bands are oblate deformed bands. Their configurations are associated with the πd5/2 [402] 52 and πg7/2[404] 72 orbitals and the strong mixing between them. Meanwhile a possible explanation of the strong mixing is given.
2009-10-01
Beattie - Bridgeman Virial expansion The above equations are suitable for moderate pressures and are usually based on either empirical constants...CR 2010-013 October 2009 A Review of Equation of State Models, Chemical Equilibrium Calculations and CERV Code Requirements for SHS Detonation...Defence R&D Canada. A Review of Equation of State Models, Chemical Equilibrium Calculations and CERV Code Requirements for SHS Detonation
Piringer, Martin; Knauder, Werner; Petz, Erwin; Schauberger, Günther
2016-09-01
Direction-dependent separation distances to avoid odour annoyance, calculated with the Gaussian Austrian Odour Dispersion Model AODM and the Lagrangian particle diffusion model LASAT at two sites, are analysed and compared. The relevant short-term peak odour concentrations are calculated with a stability-dependent peak-to-mean algorithm. The same emission and meteorological data, but model-specific atmospheric stability classes are used. The estimate of atmospheric stability is obtained from three-axis ultrasonic anemometers using the standard deviations of the three wind components and the Obukhov stability parameter. The results are demonstrated for the Austrian villages Reidling and Weissbach with very different topographical surroundings and meteorological conditions. Both the differences in the wind and stability regimes as well as the decrease of the peak-to-mean factors with distance lead to deviations in the separation distances between the two sites. The Lagrangian model, due to its model physics, generally calculates larger separation distances. For worst-case calculations necessary with environmental impact assessment studies, the use of a Lagrangian model is therefore to be preferred over that of a Gaussian model. The study and findings relate to the Austrian odour impact criteria.
Spatial calculating analysis model research of land-use change in urban fringe districts
Institute of Scientific and Technical Information of China (English)
2008-01-01
The spatial calculating analysis model is based on GIS overlay. It compartmental-izes the research district land into three spatial parts: unchanged part,converted part and increased part. By this method we can evaluate the numerical model and dynamic degree model for existing calculating changing speed of land-use. Fur-thermore the paper raises reviving the calculating analysis model of spatial infor-mation in order to predict the dynamic changing level of all sorts of land. More concretely speaking,the model is mainly to know the changing area and changing speed (increased or decreased) of different land classifications from the micro-cosmic angle and to clearly show the spatial distribution and spatio-temporal law for changing urban lands. We discover why the situation has taken place by com-bining social and economic conditions. The result indicates that the calculating analysis model of spatial information can derive more accurate procedure of spatial transference and increase of all kinds of land from the microcosmic angle. By this model and technology,we can make the research of spatio-temporal structure evolution in land-use be more systematical and deeper. The result will benefit the planning management of urban land-use of developed districts in China in the fu-ture.
Preliminary modeling of the TMI-2 accident with MELPROG-TRAC
Energy Technology Data Exchange (ETDEWEB)
Jenks, R.P.
1988-01-01
In support of Nuclear Regulatory Commission and Organization for Economic Cooperation and Development (OECD)-sponsored Three Mile Island-Unit 2 (TMI-2) Analysis Exercise studies, work has been performed to develop a simulation model of the TMI-2 plant for use with the integrated MELPROG-TRAC computer code. Numerous nuclear power plant simulation studies have been performed with the TRAC computer code in the past. Some of these addressed the TMI-2 accident or other hypothetical events at the TMI plant. In addition, studies have been previously performed with the MELPROG-TRAC code using Oconee-1 and Surry plant models. This paper describes the preliminary MELPROG-TRAC input model for severe accident analysis.
Preliminary Modeling of Corrosion/Oxidation Properties of CrAl Alloy-coated Cladding
Energy Technology Data Exchange (ETDEWEB)
Hong, Jong-Dae; Kim, Hyo Chan; Shin, Chang Hwan; Yang, Yong Sik; In, Wang Kee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2016-10-15
Accident tolerant fuel (ATF) cladding has been being developed globally after the Fukushima accident with the demands for the nuclear fuel having higher safety at normal operation conditions as well as even in a severe accident conditions. Korea Atomic Energy Research Institute (KAERI) has been developed some of remarkable ATF cladding candidates. They showed a superior oxidation/corrosion resistance in water and steam conditions to the commercial Zr alloys and totally different behaviors from commercial Zr alloys. Prior to evaluate entire fuel performance of newly developed CrAl alloy cladding by KAERI collectively, preliminary model of water-side corrosion and high temperature oxidation model were proposed. They were highly consistent with experimental results. Also this model is useful for the quantitative analysis with given with relative superior characteristics to existing commercial fuel claddings.
AN ACCURATE MODEL FOR CALCULATING CORRECTION OF PATH FLEXURE OF SATELLITE SIGNALS
Institute of Scientific and Technical Information of China (English)
LiYanxing; HuXinkang; ShuaiPing; ZhangZhongfu
2003-01-01
The propagation path of satellite signals in the atmosphere is a curve thus it,is very difficult to calculate its flexure correction accurately, a strict calculating expressions has so far not been derived. In this study, the flexure correction of the refraction curve is divided into two parts and their strict calculating expressions are derived. By use of the standard atmospheric model, the accurate flexure correction of the refraction curve is calculated for different zenith distance Z. On this basis, a calculation model is structured. This model is very simple in structure, convenient in use and high in accuracy. When Z is smaller than 85°,the accuracy of the correction exceeds 0.06mm. The flexure correction is basically proportional to tan2Z and increases rapidly with the increase of Z When Z＞50°,the correction is smaller than 0.5 mm and can be neglected. When Z＞50°, the correction must be made. When Z is 85°, 88° and 89° , the corrections are 198mm, 8.911m and 28.497 km, respectively. The calculation results shows that the correction estimate by Hopfield is correct when Z≤80°, but too small when Z=89°. The expression in this paper is applicable to any satellite.
AN ACCURATE MODEL FOR CALCULATING CORRECTION OF PATH FLEXURE OF SATELLITE SIGNALS
Institute of Scientific and Technical Information of China (English)
Li Yanxing; Hu Xinkang; Shuai Ping; Zhang Zhongfu
2003-01-01
The propagation path of satellite signals in the atmosphere is a curve thus it.is very difficult to calculate its flexure correction accurately, a strict calculating expressions has so far not been derived. In this study, the flexure correction of the refraction curve is divided into two parts and their strict calculating expressions are derived. By use of the standard atmospheric model, the accurate flexure correction of the refraction curve is calculated for different zenith distance Z. On this basis, a calculation model is structured. This model is very simple in structure, convenient in use and high in accuracy. When Z is smaller than 85°, the accuracy of the correction exceeds 0.06 mm. The flexure correction is basically proportional to tan2Z and increases rapidly with the increase of Z When Z＞50°,the correction is smaller than 0.5 mm and can be neglected.When Z＞50°, the correction must be made. When Z is 85° , 88° and 89° , the corrections are 198mm, 8. 911 m and 28. 497 km, respectively. The calculation results shows that the correction estimate by Hopfield is correct when Z≤80 °, but too small when Z=89°. The expression in this paper is applicable to any satellite.
Energy Technology Data Exchange (ETDEWEB)
Cliffe, K.A.; Morris, S.T.; Porter, J.D. [AEA Technology, Harwell (United Kingdom)
1998-05-01
NAMMU is a computer program for modelling groundwater flow and transport through porous media. This document provides an overview of the use of the program for geosphere modelling in performance assessment calculations and gives a detailed description of the program itself. The aim of the document is to give an indication of the grounds for having confidence in NAMMU as a performance assessment tool. In order to achieve this the following topics are discussed. The basic premises of the assessment approach and the purpose of and nature of the calculations that can be undertaken using NAMMU are outlined. The concepts of the validation of models and the considerations that can lead to increased confidence in models are described. The physical processes that can be modelled using NAMMU and the mathematical models and numerical techniques that are used to represent them are discussed in some detail. Finally, the grounds that would lead one to have confidence that NAMMU is fit for purpose are summarised.
Eldeeb, Safaa M; Abdelmoula, Walid M; Shah, Syed M; Fahmy, Ahmed S
2012-01-01
Age-related macular degeneration (AMD) is a major cause of blindness and visual impairment in older adults. The wet form of the disease is characterized by abnormal blood vessels forming a choroidal neovascular membrane (CNV), that result in destruction of normal architecture of the retina. Current evaluation and follow up of wet AMD include subjective evaluation of Fluorescein Angiograms (FA) to determine the activity of the lesion and monitor the progression or regression of the disease. However, this subjective evaluation prevents accurate monitoring of the disease progression or regression in response to a pharmacologic agent. In this work, we present a method that allows objective assessment of the activity of a CNV lesion which can be statistically compared across different patient and time points. The method is based on a hypothesis that the discrepancy in the time-intensity signals among the diseased and normal retinal areas are due to an implicit transfer function whose parameters can be used to characterize the retina. The method begins with parametric modeling of the temporal variation of the lesion and background intensities. Then, the values of the model parameters are used to evaluate the change in the activity of the disease. Preliminary results on five datasets show that the calculated parameters are highly correlated with the Visual Acuity (VA) of the patients.
Energy Technology Data Exchange (ETDEWEB)
Sheinman, Y.; Rosen, A. (Technion-Israel Inst. of Tech., Haifa (Israel). Faculty of Aerospace Engineering)
1991-01-01
A new model for performance calculations of grid-connected horizontal axis wind turbines is presented. This model takes into account the important dynamic characteristics of the various components comprising the turbine system, including rotor, gear-box, generator, shafts, couplings and brakes, and the grid. There is a special effort to obtain an appropriate balance between efficiency and accuracy. The model is modular and thus offers an easy implementation of new sub-models for new components, or changing of existing sub-models. The complete model of the wind turbine system is nonlinear and thus complicated. Linearization of this model leads to an eigenvalue problem that helps in understanding the dynamic characteristics of the turbine. A special reduction technique helps in reducing the size of the model and as a result increasing the model efficiency without practically decreasing its accuracy for performance calculations. (author).
Mean-Field Calculations for the Three-Dimensional Holstein Model
Institute of Scientific and Technical Information of China (English)
罗强; 刘川
2002-01-01
The electron-phonon Holstein model is studied in three spatial dimensions. It is argued that this model can be used to account for major features of the high-To BaPb1-xBixO3 and BaxK1-xBiO3 systems. Mean-field calculations are performed via a path integral representation of the model. Charge-density-wave order parameters and transition temperatures are obtained.
Energy Technology Data Exchange (ETDEWEB)
Foust, J. [Voith Hydro, Inc., York, PA (USA); Hecker, G. [Alden Research Laboratory, Inc., Holden, MA (USA); Li, S. [Alden Research Laboratory, Inc., Holden, MA (USA); Allen, G. [Alden Research Laboratory, Inc., Holden, MA (USA)
2011-10-01
The Alden turbine was developed through the U.S. Department of Energy's (DOE's) former Advanced Hydro Turbine Systems Program (1994-2006) and, more recently, through the Electric Power Research Institute (EPRI) and the DOE's Wind & Water Power Program. The primary goal of the engineering study described here was to provide a commercially competitive turbine design that would yield fish passage survival rates comparable to or better than the survival rates of bypassing or spilling flow. Although the turbine design was performed for site conditions corresponding to 92 ft (28 m) net head and a discharge of 1500 cfs (42.5 cms), the design can be modified for additional sites with differing operating conditions. During the turbine development, design modifications were identified for the spiral case, distributor (stay vanes and wicket gates), runner, and draft tube to improve turbine performance while maintaining features for high fish passage survival. Computational results for pressure change rates and shear within the runner passage were similar in the original and final turbine geometries, while predicted minimum pressures were higher for the final turbine. The final turbine geometry and resulting flow environments are expected to further enhance the fish passage characteristics of the turbine. Computational results for the final design were shown to improve turbine efficiencies by over 6% at the selected operating condition when compared to the original concept. Prior to the release of the hydraulic components for model fabrication, finite element analysis calculations were conducted for the stay vanes, wicket gates, and runner to verify that structural design criteria for stress and deflections were met. A physical model of the turbine was manufactured and tested with data collected for power and efficiency, cavitation limits, runaway speed, axial and radial thrust, pressure pulsations, and wicket gate torque. All parameters were observed to fall
AMORPHOUS SILICON ELECTRONIC STRUCTURE MODELING AND BASIC ELECTRO-PHYSICAL PARAMETERS CALCULATION
Directory of Open Access Journals (Sweden)
B. A. Golodenko
2014-01-01
Full Text Available Summary. The amorphous semiconductor has any unique processing characteristics and it is perspective material for electronic engineering. However, we have not authentic information about they atomic structure and it is essential knot for execution calculation they electronic states and electro physical properties. The author's methods give to us decision such problem. This method allowed to calculation the amorphous silicon modeling cluster atomics Cartesian coordinates, determined spectrum and density its electronic states and calculation the basics electro physical properties of the modeling cluster. At that determined numerical means of the energy gap, energy Fermi, electron concentration inside valence and conduction band for modeling cluster. The find results provides real ability for purposeful control to type and amorphous semiconductor charge carriers concentration and else provides relation between atomic construction and other amorphous substance physical properties, for example, heat capacity, magnetic susceptibility and other thermodynamic sizes.
A new timing model for calculating the intrinsic timing resolution of a scintillator detector.
Shao, Yiping
2007-02-21
The coincidence timing resolution is a critical parameter which to a large extent determines the system performance of positron emission tomography (PET). This is particularly true for time-of-flight (TOF) PET that requires an excellent coincidence timing resolution (scintillator detector: scintillation decay time and total photoelectron yield from the photon-electron conversion. However, this calculation has led to significant errors when the coincidence timing resolution reaches 1 ns or less. In this paper, a bi-exponential timing model is derived and evaluated. The new timing model includes an additional parameter of a scintillator detector: scintillation rise time. The effect of rise time on the timing resolution has been investigated analytically, and the results reveal that the rise time can significantly change the timing resolution of fast scintillators that have short decay time constants. Compared with measured data, the calculations have shown that the new timing model significantly improves the accuracy in the calculation of timing resolutions.
Minimal parameter implicit solvent model for ab initio electronic structure calculations
Dziedzic, Jacek; Skylaris, Chris-Kriton; Mostofi, Arash A; Payne, Mike C
2011-01-01
We present an implicit solvent model for ab initio electronic structure calculations which is fully self-consistent and is based on direct solution of the nonhomogeneous Poisson equation. The solute cavity is naturally defined in terms of an isosurface of the electronic density according to the formula of Fattebert and Gygi (J. Comp. Chem. 23, 6 (2002)). While this model depends on only two parameters, we demonstrate that by using appropriate boundary conditions and dispersion-repulsion contributions, solvation energies obtained for an extensive test set including neutral and charged molecules show dramatic improvement compared to existing models. Our approach is implemented in, but not restricted to, a linear-scaling density functional theory (DFT) framework, opening the path for self-consistent implicit solvent DFT calculations on systems of unprecedented size, which we demonstrate with calculations on a 2615-atom protein-ligand complex.
Energy Technology Data Exchange (ETDEWEB)
Sukegawa, Takenori; Ohshima, Soichiro; Shiraishi, Kunio; Yanagihara, Satoshi [Department of Decommissioning and Waste Management, Tokai Research Establishment, Japan Atomic Energy Research Institute, Tokai Ibaraki (Japan)
1999-02-01
Labor-hours necessary for dismantling activities are generally estimated based on experience, for example, as a form of unit productivity factors such as the relationship between labor-hours and weight of components dismantled which were obtained by actual dismantling activities. The project management data calculation models together with unit productivity factors for basic dismantling work activities were developed by analyzing the data obtained from the Japan Power Demonstration Reactor (JPDR) dismantling project, which will be applicable to estimation of labor-hours in various dismantling conditions. Typical work breakdown structures were also prepared by categorizing repeatable basic dismantling work activities for effective planning of dismantling activities. The labor-hours for dismantling the JPDR components and structures were calculated by using the code system for management of reactor decommissioning (COSMARD), in which the work breakdown structures and the calculation models were contained. It was confirmed that the labor-hours could be easily estimated by COSMARD through the calculations. This report describes the labor-hour calculation models and application of these models to COSMARD. (author)
Modification method of numerical calculation of heat flux over dome based on turbulence models
Zhang, Daijun; Luo, Haibo; Zhang, Junchao; Zhang, Xiangyue
2016-10-01
For the optical guidance system flying at low altitude and high speed, the calculation of turbulent convection heat transfer over its dome is the key to designing this kind of aircraft. RANS equations-based turbulence models are of high computation efficiency and their calculation accuracy can satisfy the engineering requirement. But for the calculation of the flow in the shock layer of strong entropy and pressure disturbances existence, especially of aerodynamic heat, some parameters in the RANS energy equation are necessary to be modified. In this paper, we applied turbulence models on the calculation of the heat flux over the dome of sphere-cone body at zero attack. Based on Billig's results, the shape and position of detached shock were extracted in flow field using multi-block structured grid. The thermal conductivity of the inflow was set to kinetic theory model with respect to temperature. When compared with Klein's engineering formula at the stagnation point, we found that the results of turbulent models were larger. By analysis, we found that the main reason of larger values was the interference from entropy layer to boundary layer. Then thermal conductivity of inflow was assigned a fixed value as equivalent thermal conductivity in order to compensate the overestimate of the turbulent kinetic energy. Based on the SST model, numerical experiments showed that the value of equivalent thermal conductivity was only related with the Mach number. The proposed modification approach of equivalent thermal conductivity for inflow in this paper could also be applied to other turbulence models.
The Calculation Model for Operation Cost of Coal Resources Development Based on ANN
Institute of Scientific and Technical Information of China (English)
刘海滨
2004-01-01
On the basis of analysis and selection of factors influencing operation cost of coal resources development, fuzzy set method and artificial neural network (ANN) were adopted to set up the classification analysis model of coal resources. The collected samples were classified by using this model. Meanwhile, the pattern recognition model for classifying of the coal resources was built according to the factors influencing operation cost. Based on the results achieved above, in the light of the theory of information diffusion, the calculation model for operation cost of coal resources development has been presented and applied in practice, showing that these models are reasonable.
Recoilless fractions calculated with the nearest-neighbour interaction model by Kagan and Maslow
Kemerink, G. J.; Pleiter, F.
1986-08-01
The recoilless fraction is calculated for a number of Mössbauer atoms that are natural constituents of HfC, TaC, NdSb, FeO, NiO, EuO, EuS, EuSe, EuTe, SnTe, PbTe and CsF. The calculations are based on a model developed by Kagan and Maslow for binary compounds with rocksalt structure. With the exception of SnTe and, to a lesser extent, PbTe, the results are in reasonable agreement with the available experimental data and values derived from other models.
Comparison of truncated shell model calculations in the laboratory and intrinsic systems
Energy Technology Data Exchange (ETDEWEB)
Catara, F.; Insolia, A.; Sambataro, M.; Maglione, E.; Vitturi, A.
1985-08-01
We perform, in the case of particles moving in a single-j level, shell model calculations in which the angular momentum of the individual pairs is restricted to a maximum value. The comparison with the full calculation shows the need for including at least the G pairs in the model space in order to reproduce the correct moments of inertia and transition rates of the different rotational bands. We also show that a level scheme very close to that obtained in the laboratory system can be alternatively obtained by angular momentum projection starting from intrinsic states evaluated in the intrinsic frame.
CALCULATIONS OF STRETCHING VIBRATIONAL ENERGYLEVELS OF THE CH3I MOLECULE BY A NONLINEAR MODEL
Institute of Scientific and Technical Information of China (English)
ZHU JUN; GOU QING-QUAN
2001-01-01
A nonlinear model, i.e. the quantized discrete self-trapping equation, is applied to calculate the highly excited CH stretching vibrational energy levels of the CH3I molecule in the liquid phase at the electronic ground state up to n=8. The obtained results agree well with the experimental data and with those obtained from local mode model calculations. We note that the dominant feature of the methyl CH stretching vibrational energy levels of the CH3I molecule is a pattern of local mode pairs. When n ＞ 7, all the vibrational energy of the CH3 group can nearly be localized on a single CH bond.
On Calculating the Current-Voltage Characteristic of Multi-Diode Models for Organic Solar Cells
Roberts, Ken
2016-01-01
We provide an alternative formulation of the exact calculation of the current-voltage characteristic of solar cells which have been modeled with a lumped parameters equivalent circuit with one or two diodes. Such models, for instance, are suitable for describing organic solar cells whose current-voltage characteristic curve has an inflection point, also known as an S-shaped anomaly. Our formulation avoids the risk of numerical overflow in the calculation. It is suitable for implementation in Fortran, C or on micro-controllers.
A Model to Calculate the Return on Investment After a Software Implementation
Directory of Open Access Journals (Sweden)
PADUAM, T. C.
2015-06-01
Full Text Available Currently the organization has been concerned with the analysis of the impact of IT investments. Economic pressures, combined with years of significant IT spending without demonstrating clear returns, forced companies to improve their financial practices and justify better and more clearly every penny invested way. Thus, this article presents the model to calculate the return on investment after deploying software. This model was generated from two experiments conducted in the laboratory and in the field, applied in southern Brazil, which showed effective action to catch the post-deployment time metrics. Nevertheless, this article may be applicable to all companies wishing to calculate the temporal return from a deployment
DEFF Research Database (Denmark)
Mattsson, T.R.; Wahnström, G.; Bengtsson, L.
1997-01-01
First-principles density-functional calculations of hydrogen adsorption on the Ni (001) surface have been performed in order to get a better understanding of adsorption and diffusion of hydrogen on metal surfaces. We find good agreement with experiments for the adsorption energy, binding distance...
Ulmer, W
2010-01-01
We have developed a model for proton depth dose and lateral distributions based on Monte Carlo calculations (GEANT4) and an integration procedure of the Bethe-Bloch equation (BBE). The model accounts for the transport of primary and secondary protons, the creation of recoil protons and heavy recoil nuclei as well as lateral scattering of these contributions. The buildup, which is experimentally observed in higher energy depth dose curves, is modeled by inclusion of two different origins: 1. Secondary reaction protons with a contribution of ca. 65 % of the buildup (for monoenergetic protons). 2. Landau tails as well as Gaussian type of fluctuations for range straggling effects. All parameters of the model for initially monoenergetic proton beams have been obtained from Monte Carlo calculations or checked by them. Furthermore, there are a few parameters, which can be obtained by fitting the model to measured depth dose curves in order to describe individual characteristics of the beamline - the most important b...
A model of the circulating blood for use in radiation dose calculations
Energy Technology Data Exchange (ETDEWEB)
Hui, T.E.; Poston, J.W. Sr.
1987-01-01
Over the last few years there has been a significant increase in the use of radionuclides in leukocyte, platelet, and erythrocyte imaging procedures. Radiopharmaceutical used in these procedures are confined primarily to the blood, have short half-lives, and irradiate the body as they move through the circulatory system. There is a need for a model, to describe the circulatory system in an adult human, which can be used to provide radiation absorbed dose estimates for these procedures. A simplified model has been designed assuming a static circulatory system and including major organs of the body. The model has been incorporated into the MIRD phantom and calculations have been completed for a number of exposure situations and radionuclides of clinical importance. The model will be discussed in detail and results of calculations using this model will be presented.
A model of the circulating blood for use in radiation dose calculations
Energy Technology Data Exchange (ETDEWEB)
Hui, T.E.; Poston, J.W. Sr.
1987-12-31
Over the last few years there has been a significant increase in the use of radionuclides in leukocyte, platelet, and erythrocyte imaging procedures. Radiopharmaceutical used in these procedures are confined primarily to the blood, have short half-lives, and irradiate the body as they move through the circulatory system. There is a need for a model, to describe the circulatory system in an adult human, which can be used to provide radiation absorbed dose estimates for these procedures. A simplified model has been designed assuming a static circulatory system and including major organs of the body. The model has been incorporated into the MIRD phantom and calculations have been completed for a number of exposure situations and radionuclides of clinical importance. The model will be discussed in detail and results of calculations using this model will be presented.
Directory of Open Access Journals (Sweden)
B. Kravitz
2015-06-01
simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space. We discuss experiment designs, as well as the rationale for those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1 GeoMIP experiments. This is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.
Cognitive Work Analysis: Preliminary Data for a Model of Problem Solving Strategies
Rothmayer, Mark; Blue, Jennifer
2007-10-01
Investigations into problem solving strategies are part of the field of physics education research where investigators seek to improve physics instruction by conducting basic research of problem solving abilities among students, differences in knowledge representations between experts and novices, and how to transfer knowledge structures more effectively onto novices. We developed a new conceptual research tool in our laboratory, where we could potentially map the step by step flow of problem solving strategies among experts and novices. This model is derived from the theory of Cognitive Work Analysis, which is grounded in ecological psychology, and as far as we know it has never been applied to a knowledge domain like physics. We collected survey data from 140 undergraduates enrolled in an algebra based introductory physics course at Miami University as part of a larger study aimed to test the validity of the model. Preliminary data will be presented and discussed.
Campolina, Daniel de A. M.; Lima, Claubia P. B.; Veloso, Maria Auxiliadora F.
2014-06-01
For all the physical components that comprise a nuclear system there is an uncertainty. Assessing the impact of uncertainties in the simulation of fissionable material systems is essential for a best estimate calculation that has been replacing the 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. In this work a sample space of MCNPX calculations was used to propagate the uncertainty. The sample size was optimized using the Wilks formula for a 95th percentile and a two-sided statistical tolerance interval of 95%. Uncertainties in input parameters of the reactor considered included geometry dimensions and densities. It was showed the capacity of the sampling-based method for burnup when the calculations sample size is optimized and many parameter uncertainties are investigated together, in the same input.
Unified description of pf-shell nuclei by the Monte Carlo shell model calculations
Energy Technology Data Exchange (ETDEWEB)
Mizusaki, Takahiro; Otsuka, Takaharu [Tokyo Univ. (Japan). Dept. of Physics; Honma, Michio
1998-03-01
The attempts to solve shell model by new methods are briefed. The shell model calculation by quantum Monte Carlo diagonalization which was proposed by the authors is a more practical method, and it became to be known that it can solve the problem with sufficiently good accuracy. As to the treatment of angular momentum, in the method of the authors, deformed Slater determinant is used as the basis, therefore, for making angular momentum into the peculiar state, projected operator is used. The space determined dynamically is treated mainly stochastically, and the energy of the multibody by the basis formed as the result is evaluated and selectively adopted. The symmetry is discussed, and the method of decomposing shell model space into dynamically determined space and the product of spin and isospin spaces was devised. The calculation processes are shown with the example of {sup 50}Mn nuclei. The calculation of the level structure of {sup 48}Cr with known exact energy can be done with the accuracy of peculiar absolute energy value within 200 keV. {sup 56}Ni nuclei are the self-conjugate nuclei of Z=N=28. The results of the shell model calculation of {sup 56}Ni nucleus structure by using the interactions of nuclear models are reported. (K.I.)
Unified description of pf-shell nuclei by the Monte Carlo shell model calculations
Energy Technology Data Exchange (ETDEWEB)
Mizusaki, Takahiro; Otsuka, Takaharu [Tokyo Univ. (Japan). Dept. of Physics; Honma, Michio
1998-03-01
The attempts to solve shell model by new methods are briefed. The shell model calculation by quantum Monte Carlo diagonalization which was proposed by the authors is a more practical method, and it became to be known that it can solve the problem with sufficiently good accuracy. As to the treatment of angular momentum, in the method of the authors, deformed Slater determinant is used as the basis, therefore, for making angular momentum into the peculiar state, projected operator is used. The space determined dynamically is treated mainly stochastically, and the energy of the multibody by the basis formed as the result is evaluated and selectively adopted. The symmetry is discussed, and the method of decomposing shell model space into dynamically determined space and the product of spin and isospin spaces was devised. The calculation processes are shown with the example of {sup 50}Mn nuclei. The calculation of the level structure of {sup 48}Cr with known exact energy can be done with the accuracy of peculiar absolute energy value within 200 keV. {sup 56}Ni nuclei are the self-conjugate nuclei of Z=N=28. The results of the shell model calculation of {sup 56}Ni nucleus structure by using the interactions of nuclear models are reported. (K.I.)
Energy Technology Data Exchange (ETDEWEB)
Murata, Isao [Osaka Univ., Suita (Japan); Mori, Takamasa; Nakagawa, Masayuki; Itakura, Hirofumi
1996-03-01
The method to calculate neutronics parameters of a core composed of randomly distributed spherical fuels has been developed based on a statistical geometry model with a continuous energy Monte Carlo method. This method was implemented in a general purpose Monte Carlo code MCNP, and a new code MCNP-CFP had been developed. This paper describes the model and method how to use it and the validation results. In the Monte Carlo calculation, the location of a spherical fuel is sampled probabilistically along the particle flight path from the spatial probability distribution of spherical fuels, called nearest neighbor distribution (NND). This sampling method was validated through the following two comparisons: (1) Calculations of inventory of coated fuel particles (CFPs) in a fuel compact by both track length estimator and direct evaluation method, and (2) Criticality calculations for ordered packed geometries. This method was also confined by applying to an analysis of the critical assembly experiment at VHTRC. The method established in the present study is quite unique so as to a probabilistic model of the geometry with a great number of spherical fuels distributed randomly. Realizing the speed-up by vector or parallel computations in future, it is expected to be widely used in calculation of a nuclear reactor core, especially HTGR cores. (author).
Program realization of mathematical model of kinetostatical calculation of flat lever mechanisms
Directory of Open Access Journals (Sweden)
M. A. Vasechkin
2016-01-01
Full Text Available Global computerization determined the dominant position of the analytical methods for the study of mechanisms. As a result, kinetostatics analysis of mechanisms using software packages is an important part of scientific and practical activities of engineers and designers. Therefore, software implementation of mathematical models kinetostatical calculating mechanisms is of practical interest. The mathematical model obtained in [1]. In the language of Turbo Pascal developed a computer procedure that calculates the forces in kinematic pairs in groups Assur (GA and a balancing force at the primary level. Before use appropriate computational procedures it is necessary to know all external forces and moments acting on the GA and to determine the inertial forces and moments of inertia forces. The process of calculations and constructions of the provisions of the mechanism can be summarized as follows. Organized cycle in which to calculate the position of an initial link of the mechanism. Calculate the position of the remaining links of the mechanism by referring to relevant procedures module DIADA in GA [2,3]. Using the graphics mode of the computer displaying on the display the position of the mechanism. The computed inertial forces and moments of inertia forces. Turning to the corresponding procedures of the module, calculated all the forces in kinematic pairs and the balancing force at the primary level. In each kinematic pair build forces and their direction with the help of simple graphical procedures. The magnitude of these forces and their direction are displayed in a special window with text mode. This work contains listings of the test programs MyTеst, is an example of using computing capabilities of the developed module. As a check on the calculation procedures of module in the program is reproduced an example of calculating the balancing forces according to the method of Zhukovsky (Zhukovsky lever.
Gann, Candace J.; Kunnavatana, S. Shanun
2016-01-01
This preliminary study investigated the use of the Function-Based Intervention Decision Model (Decision Model; Umbreit, Ferro, Liaupsin, & Lane, 2007) to improve teacher treatment integrity for a function-based classroom management plan. The participants were a special education teacher and three elementary-age students receiving special…
A single-source photon source model of a linear accelerator for Monte Carlo dose calculation.
Nwankwo, Obioma; Glatting, Gerhard; Wenz, Frederik; Fleckenstein, Jens
2017-01-01
To introduce a new method of deriving a virtual source model (VSM) of a linear accelerator photon beam from a phase space file (PSF) for Monte Carlo (MC) dose calculation. A PSF of a 6 MV photon beam was generated by simulating the interactions of primary electrons with the relevant geometries of a Synergy linear accelerator (Elekta AB, Stockholm, Sweden) and recording the particles that reach a plane 16 cm downstream the electron source. Probability distribution functions (PDFs) for particle positions and energies were derived from the analysis of the PSF. These PDFs were implemented in the VSM using inverse transform sampling. To model particle directions, the phase space plane was divided into a regular square grid. Each element of the grid corresponds to an area of 1 mm2 in the phase space plane. The average direction cosines, Pearson correlation coefficient (PCC) between photon energies and their direction cosines, as well as the PCC between the direction cosines were calculated for each grid element. Weighted polynomial surfaces were then fitted to these 2D data. The weights are used to correct for heteroscedasticity across the phase space bins. The directions of the particles created by the VSM were calculated from these fitted functions. The VSM was validated against the PSF by comparing the doses calculated by the two methods for different square field sizes. The comparisons were performed with profile and gamma analyses. The doses calculated with the PSF and VSM agree to within 3% /1 mm (>95% pixel pass rate) for the evaluated fields. A new method of deriving a virtual photon source model of a linear accelerator from a PSF file for MC dose calculation was developed. Validation results show that the doses calculated with the VSM and the PSF agree to within 3% /1 mm.
Institute of Scientific and Technical Information of China (English)
ZHANG Hongsheng; ZHAO Jiachen; LI Penghui; YUE Wenhan; WANG Zhenxiang
2016-01-01
Since the wind wave model Simulating Waves Nearshore (SWAN) cannot effectively simulate the wave fields near the lateral boundaries, the change characteristics and the distortion ranges of calculated wave factors including wave heights, periods, directions, and lengths near the lateral boundaries of calculation domain are carefully studied in the case of different water depths and wind speeds respectively. The calculation results show that the effects of the variety of water depth and wind speed on the modeled different wave factors near the lateral boundaries are different. In the case of a certain wind speed, the greater the water depth is, the greater the distortion range is. In the case of a certain water depth, the distortion ranges defined by the relative errors of wave heights, periods, and lengths are different from those defined by the absolute errors of the corresponding wave factors. Moreover, the distortion ranges defined by the relative errors decrease with the increase of wind speed;whereas the distortion ranges defined by the absolute errors change a little with the variety of wind speed. The distortion range of wave direction decreases with the increase of wind speed. The calculated wave factors near the lateral boundaries with the SWAN model in the actual physical areas, such as Lake Taihu and Lake Dianshan considered in this study, are indeed distorted if the calculation domains are not enlarged on the basis of actual physical areas. Therefore, when SWAN is employed to calculate the wind wave fields near the shorelines of sea or inland lakes, the appropriate approaches must be adopted to reduce the calculation errors.
Spin-splitting calculation for zincblende semiconductors using an atomic bond-orbital model.
Kao, Hsiu-Fen; Lo, Ikai; Chiang, Jih-Chen; Chen, Chun-Nan; Wang, Wan-Tsang; Hsu, Yu-Chi; Ren, Chung-Yuan; Lee, Meng-En; Wu, Chieh-Lung; Gau, Ming-Hong
2012-10-17
We develop a 16-band atomic bond-orbital model (16ABOM) to compute the spin splitting induced by bulk inversion asymmetry in zincblende materials. This model is derived from the linear combination of atomic-orbital (LCAO) scheme such that the characteristics of the real atomic orbitals can be preserved to calculate the spin splitting. The Hamiltonian of 16ABOM is based on a similarity transformation performed on the nearest-neighbor LCAO Hamiltonian with a second-order Taylor expansion k at the Γ point. The spin-splitting energies in bulk zincblende semiconductors, GaAs and InSb, are calculated, and the results agree with the LCAO and first-principles calculations. However, we find that the spin-orbit coupling between bonding and antibonding p-like states, evaluated by the 16ABOM, dominates the spin splitting of the lowest conduction bands in the zincblende materials.
Fontanot, Fabio; Silva, Laura; Monaco, Pierluigi; Skibba, Ramin; 10.1111/j.1365-2966.2008.14126.x
2009-01-01
The treatment of dust attenuation is crucial in order to compare the predictions of galaxy formation models with multiwavelength observations. Most past studies have either used simple analytic prescriptions or else full radiative transfer (RT) calculations. Here, we couple star formation histories and morphologies predicted by the semi-analytic galaxy formation model MORGANA with RT calculations from the spectrophotometric and dust code GRASIL to create a library of galaxy SEDs from the UV/optical through the far Infrared, and compare the predictions of the RT calculations with analytic prescriptions. We consider a low and high redshift sample, as well as an additional library constructed with empirical, non-cosmological star formation histories and simple (pure bulge or disc) morphologies. Based on these libraries, we derive fitting formulae for the effective dust optical depth as a function of galaxy physical properties such as metallicity, gas mass, and radius. We show that such fitting formulae can predi...
Energy Technology Data Exchange (ETDEWEB)
Waegeneers, Nadia, E-mail: nadia.waegeneers@var.fgov.be; Ruttens, Ann; De Temmerman, Ludwig
2011-06-15
A chain model was developed to calculate the flow of cadmium from soil, drinking water and feed towards bovine tissues. The data used for model development were tissue Cd concentrations of 57 bovines and Cd concentrations in soil, feed and drinking water, sampled at the farms were the bovines were reared. Validation of the model occurred with a second set of measured tissue Cd concentrations of 93 bovines of which age and farm location were known. The exposure part of the chain model consists of two parts: (1) a soil-plant transfer model, deriving cadmium concentrations in feed from basic soil characteristics (pH and organic matter content) and soil Cd concentrations, and (2) bovine intake calculations, based on typical feed and water consumption patterns for cattle and Cd concentrations in feed and drinking water. The output of the exposure model is an animal-specific average daily Cd intake, which is then taken forward to a kinetic uptake model in which time-dependent Cd concentrations in bovine tissues are calculated. The chain model was able to account for 65%, 42% and 32% of the variation in observed kidney, liver and meat Cd concentrations in the validation study. - Research highlights: {yields} Cadmium transfer from soil, drinking water and feed to bovine tissues was modeled. {yields} The model was based on 57 bovines and corresponding feed and soil Cd concentrations. {yields} The model was validated with an independent data set of 93 bovines. {yields} The model explained 65% of variation in kidney Cd in the validation study.
Energy Technology Data Exchange (ETDEWEB)
Hartley, Lee; Cox, Ian; Hunter, Fiona; Jackson, Peter; Joyce, Steve; Swift, Ben [Serco Assurance, Risley (United Kingdom); Gylling, Bjoern; Marsic, Niko [Kemakta Konsult AB, Stockholm (Sweden)
2005-05-01
The Swedish Nuclear Fuel and Waste Management Company (SKB) carries out site investigations in two different candidate areas in Sweden with the objective of describing the in-situ conditions for a bedrock repository for spent nuclear fuel. The site characterisation work is divided into two phases, an initial site investigation phase (IPLU) and a complete site investigation phase (KPLU). The results of IPLU are used as a basis for deciding on a subsequent KPLU phase. On the basis of the KPLU investigations a decision is made as to whether detailed characterisation will be performed (including sinking of a shaft). An integrated component in the site characterisation work is the development of site descriptive models. These comprise basic models in three dimensions with an accompanying text description. Central in the modelling work is the geological model, which provides the geometrical context in terms of a model of deformation zones and the rock mass between the zones. Using the geological and geometrical description models as a basis, descriptive models for other geo-disciplines (hydrogeology, hydro-geochemistry, rock mechanics, thermal properties and transport properties) will be developed. Great care is taken to arrive at a general consistency in the description of the various models and assessment of uncertainty and possible needs of alternative models. Here, a numerical model is developed on a regional-scale (hundreds of square kilometres) to understand the zone of influence for groundwater flow that affects the Forsmark area. Transport calculations are then performed by particle tracking from a local-scale release area (a few square kilometres) to identify potential discharge areas for the site and using greater grid resolution. The main objective of this study is to support the development of a preliminary Site Description of the Forsmark area on a regional-scale based on the available data of 30 June 2004 and the previous Site Description. A more specific
Comparison of Steady-State SVC Models in Load Flow Calculations
DEFF Research Database (Denmark)
Chen, Peiyuan; Chen, Zhe; Bak-Jensen, Birgitte
2008-01-01
This paper compares in a load flow calculation three existing steady-state models of static var compensator (SVC), i.e. the generator-fixed susceptance model, the total susceptance model and the firing angle model. The comparison is made in terms of the voltage at the SVC regulated bus, equivalent...... SVC susceptance at the fundamental frequency and the load flow convergence rate both when SVC is operating within and on the limits. The latter two models give inaccurate results of the equivalent SVC susceptance as compared to the generator model due to the assumption of constant voltage when the SVC...... is operating within the limits. This may underestimate or overestimate the SVC regulating capability. Two modified models are proposed to improve the SVC regulated voltage according to its steady-state characteristic. The simulation results of the two modified models show the improved accuracy...
Directory of Open Access Journals (Sweden)
Saleh Alsubari
2011-09-01
Full Text Available In this paper, we present the mechanical models that are devoted to the elastic properties of one-dimensional composite. We have compared the equivalent coefficients of one-dimensional composite, resulting from different models. The validation of the results was made through effective experiments on a one-dimensional composite consisting of fibers of alumina and a matrix of aluminum. This study allows us to better assess the rigidity of composite structures, and the results of calculation of the mechanical behavior, resulting from each model. It appears that the finite element model is the best suited to the approach of a refined conception. For more insurance, we have chosen to make our calculations by finite element in the three-dimensional case, using the technique of homogenization by asymptotic development.
Direct Calculation of Ice Homogeneous Nucleation Rate for a Molecular Model of Water
Haji-Akbari, Amir
2015-01-01
Ice formation is ubiquitous in nature, with important consequences in a variety of systems and environments, including biological cells [1], soil [2], aircraft [3], transportation infrastructure [4] and atmospheric clouds [5,6]. However, its intrinsic kinetics and microscopic mechanism are difficult to discern with current experiments. Molecular simulations of ice nucleation are also challenging, and direct rate calculations have only been performed for coarse-grained models of water [7-9]. For the more realistic molecular models, only indirect estimates have been obtained, e.g.~by assuming the validity of classical nucleation theory [10]. Here, we use a path sampling approach to perform the first direct rate calculation of homogeneous nucleation of ice in a molecular model of water. We use TIP4P/Ice [11], the most accurate among the existing molecular models for studying ice polymorphs. By using a novel topological order parameter for distinguishing different polymorphs, we are able to identify a freezing me...
Monte Carlo calculation model for heat radiation of inclined cylindrical flames and its application
Chang, Zhangyu; Ji, Jingwei; Huang, Yuankai; Wang, Zhiyi; Li, Qingjie
2017-02-01
Based on Monte Carlo method, a calculation model and its C++ calculating program for radiant heat transfer from an inclined cylindrical flame are proposed. In this model, the total radiation energy of the inclined cylindrical flame is distributed equally among a certain number of energy beams, which are emitted randomly from the flame surface. The incident heat flux on a surface is calculated by counting the number of energy beams which could reach the surface. The paper mainly studies the geometrical evaluation criterion for validity of energy beams emitted by inclined cylindrical flames and received by other surfaces. Compared to Mudan's formula results for a straight cylinder or a cylinder with 30° tilt angle, the calculated view factors range from 0.0043 to 0.2742 and the predicted view factors agree well with Mudan's results. The changing trend and values of incident heat fluxes computed by the model is consistent with experimental data measured by Rangwala et al. As a case study, incident heat fluxes on a gasoline tank, both the side and the top surface are calculated by the model. The heat radiation is from an inclined cylindrical flame generated by another 1000 m3 gasoline tank 4.6 m away from it. The cone angle of the flame to the adjacent oil tank is 45° and the polar angle is 0°. The top surface and the side surface of the tank are divided into 960 and 5760 grids during the calculation, respectively. The maximum incident heat flux on the side surface is 39.64 and 51.31 kW/m2 on the top surface. Distributions of the incident heat flux on the surface of the oil tank and on the ground around the fire tank are obtained, too.
A new simulation model for calculating the internal exposure of some radionuclides
Directory of Open Access Journals (Sweden)
Mahrous Ayman
2009-01-01
Full Text Available A new model based on a series of mathematical functions for estimating excretion rates following the intake of nine different radionuclides is presented in this work. The radionuclides under investigation are: cobalt, iodine, cesium, strontium, ruthenium, radium, thorium, plutonium, and uranium. The committed effective dose has been calculated by our model so as to obtain the urinary and faecal excretion rates for each radionuclide. The said model is further validated by a comparison with the widely spread Mondal software and a simulation program. The results obtained show a harmony between the Mondal package and the model we have constructed.
Calculation of Surface Tensions of Polar Mixtures with a Simplified Gradient Theory Model
DEFF Research Database (Denmark)
Zuo, You-Xiang; Stenby, Erling Halfdan
1996-01-01
Key Words: Thermodynamics, Simplified Gradient Theory, Surface Tension, Equation of state, Influence Parameter.In this work, assuming that the number densities of each component in a mixture across the interface between the coexisting vapor and liquid phases are linearly distributed, we developed...... a simplified gradient theory (SGT) model for computing surface tensions. With this model, it is not required to solve the time-consuming density profile equations of the gradient theory model. The SRK EOS was applied to calculate the properties of the homogeneous fluid. First, the SGT model was used to predict...
Development of a Coolant Analysis Model for the Sodium Reactivity Calculation in the KALIMER Core
Energy Technology Data Exchange (ETDEWEB)
Chang, Won Pyo; Lee, Yong Bum
2006-06-15
The present research concerns about developing a computational algorithm for the analysis of post boiling fuel temperature, based on the sodium boiling model proposed by USNRC. The model selection comes from the fact that the analysis of LMR sodium boiling had already been done using this model being coupled with SSC-L, and therefore its theory is believed to be a quite adequate option for compatibility to SSC-K. Physical phenomena characterizing UTO, ULOF, and ULOHS for KALIMER are analyzed for evaluation of the developed algorithm. The results obtained from the calculation are also compared with those of a previous model to confirm physical consistencies.
Dynamic mathematical model and numerical calculation method on spontaneous combustion of loose coal
Institute of Scientific and Technical Information of China (English)
WEN Hu(文虎)
2003-01-01
Through the experiment of coal spontaneous combustion and relationship particle size with oxidation character of loose coal, some calculation formula of characteristic parameters is got in the process of coal spontaneous combustion. According to these theories of porous medium hydrodynamics, mass transfer and heat transfer, mathematical models of air leak field, oxygen concentration field and temperature field are set up. Through experimental and theoretical analysis, 3-D dynamic mathematical model of coal spontaneous combustion is set up. The method of ascertaining boundary condition of model is analyzed, and finite difference method is adopted to solve 2-D mathematical model.
KOELINK, MH; DEMUL, FFM; GREVE, J; GRAAFF, R; DASSEL, ACM; AARNOUDSE, JG
1992-01-01
In addition to the static cubic lattice model for photon migration in turbid biological media by Bonner et al. [J. Opt. Soc. Am. A 4, 423-432 (1987)], a dynamic method is presented to calculate the average absolute Doppler shift as a function of the distance between the point of injection of photons
Antarctic ice volume for the last 740 ka calculated with a simple ice sheet model
Oerlemans, J.
2005-01-01
Fluctuations in the volume of the Antarctic ice sheet for the last 740 ka are calculated by forcing a simple ice sheet model with a sea-level history (from a composite deep sea δ18O record) and a temperature history (from the Dome C deuterium record). Antarctic ice volume reaches maximum values of a
Model-Independent Calculation of Radiative Neutron Capture on Lithium-7
Rupak, Gautam; Higa, Renato
2011-01-01
The radiative neutron capture on lithium-7 is calculated model independently using a low-energy halo effective field theory. The cross section is expressed in terms of scattering parameters directly related to the S-matrix elements. It depends on the poorly known p-wave effective range parameter r(1
A model to calculate cardiac output in hemodialysis patients by thermodilution
Directory of Open Access Journals (Sweden)
Alayoud Ahmed
2012-06-01
Full Text Available Abstract The Blood Temperature Monitor module (BTM is used to measure recirculation by thermodilution in dialysis. Numerous studies have confirmed its interest in the measuring of the vascular access flow. In this letter we describe a model to calculate cardiac output in dialysis by the BTM.
A Simplified Model to Calculate AC Losses in Large 2G HTS Coils
DEFF Research Database (Denmark)
Song, Xiaowei (Andy); Mijatovic, Nenad; Jensen, Bogi Bech;
2015-01-01
AC losses are of great significance to quantify the performance of high temperature superconducting (HTS) devices. This paper presents a simplified model to calculate AC losses in large 2G HTS coils, which serves as a baseline to study HTS large scale applications such as electric machines. The m...
Seldam, C.A. ten; Groot, S.R. de
From Jensen's and Gombás' modification of the statistical Thomas-Fermi atom model, a theory for compressed atoms is developed by changing the boundary conditions. Internal kinetic energy and polarizability of argon are calculated as functions of pressure. At 1000 atm. an internal kinetic energy of
40 CFR 600.207-93 - Calculation of fuel economy values for a model type.
2010-07-01
... base level. (7) For alcohol dual fuel automobiles and natural gas dual fuel automobiles the procedures... combined fuel economy values from the tests performed using gasoline or diesel test fuel. (ii) Calculate... economy values for the model type. (5) For alcohol dual fuel automobiles and natural gas dual fuel...
Large-scale shell-model calculations on the spectroscopy of $N<126$ Pb isotopes
Qi, Chong; Fu, G J
2016-01-01
Large-scale shell-model calculations are carried out in the model space including neutron-hole orbitals $2p_{1/2}$, $1f_{5/2}$, $2p_{3/2}$, $0i_{13/2}$, $1f_{7/2}$ and $0h_{9/2}$ to study the structure and electromagnetic properties of neutron deficient Pb isotopes. An optimized effective interaction is used. Good agreement between full shell-model calculations and experimental data is obtained for the spherical states in isotopes $^{194-206}$Pb. The lighter isotopes are calculated with an importance-truncation approach constructed based on the monopole Hamiltonian. The full shell-model results also agree well with our generalized seniority and nucleon-pair-approximation truncation calculations. The deviations between theory and experiment concerning the excitation energies and electromagnetic properties of low-lying $0^+$ and $2^+$ excited states and isomeric states may provide a constraint on our understanding of nuclear deformation and intruder configuration in this region.
Baraffe, [No Value; Alibert, Y; Mera, D; Charbrier, G; Beaulieu, JP
1998-01-01
We have computed stellar evolutionary models for stars in a mass range characteristic of Cepheid variables (3
Models for calculating phreatic water evaporation on bare and Tamarix-vegetated lands
Institute of Scientific and Technical Information of China (English)
HU Shunjun; TIAN Changyan; SONG Yudong; CHEN Xiaobing; LI Yuetan
2006-01-01
Groundwater is the main source of water consumption of natural vegetation in arid regions.It is an effective approach to study ecological water demand of natural vegetation by phreatic evaporation.In order to study the ecological water demand of Tarim river basin, based on the observation data of phreatic evaporation on bare lands at the Aksu Water Balance Experimental station from 1989 to 1996, by analyzing the relationship of phreatic evaporation,depth of phreatic surface and evaporation of water,taking the limit rate of phreatic evaporation as the control condition, and based on the objective law that the relation between phreatic evaporation and evaporation of water is nonlinear, we establish models for calculating phreatic evaporation on bare land,which can fully reflect the law of phreatic evaporation in the Tarim river basin. According to the data of depth of phreatic surface and soil moisture when pheratic level decline is caused just by evapotranspiration on Tamarix-vegetated land from 2003 to 2004, we calculate the amount of phreatic evaporation and set up models for calculating phreatic evaporation on Tamarix- vegetated land. Phreatic evaporation on bare land and Tamarix-vegetated land could be transformed each other by a Tamarix vegetation conversion coefficient. The test results show that the calculation accuracy of the models is high and the models are suitable for Tarim river basin.
Svizhenko, Alexel; Anantram, M. P.; Maiti, Amitesh
2003-01-01
This paper presents viewgraphs on the modeling of the electromechanical response of carbon nanotubes, utilizing molecular dynamics and transport calculations. The topics include: 1) Simulations of the experiment; 2) Effect of diameter, length and temperature; and 3) Study of sp3 coordination-"The Table experiment".
Comparison of inverse dynamics calculated by two- and three-dimensional models during walking
DEFF Research Database (Denmark)
Alkjaer, T; Simonsen, E B; Dyhre-Poulsen, P
2001-01-01
The purpose of the study was to compare joint moments calculated by a two- (2D) and a three-dimensional (3D) inverse dynamics model to examine how the different approaches influenced the joint moment profiles. Fifteen healthy male subjects participated in the study. A five-camera video system rec...
Model calculations of the age of firn air across the Antarctic continent
2004-01-01
The age of firn air in Antarctica at pore close-off depth is only known for a few specific sites where firn air has been sampled for analyses. We present a model that calculates the age of firn air at pore close-off depth for the entire Antarctic continent. The model basically uses four meteorological parameters as input (surface temperature, pressure, accumulation rate and wind speed). Using parameterisations for surface snow density, pore close-off density and tortuosity, ...
Karandashev, Yakov M
2016-01-01
In this paper we propose and realize (the code is publicly available at https://github.com/Thrawn1985/2D-Partition-Function) an algorithm for exact calculation of partition function for planar graph models with binary spins. The complexity of the algorithm is O(N^2). Test experiments shows good agreement with Onsager's analytical solution for two-dimensional Ising model of infinite size.
Stochastic estimation of level density in nuclear shell-model calculations
Directory of Open Access Journals (Sweden)
Shimizu Noritaka
2016-01-01
Full Text Available An estimation method of the nuclear level density stochastically based on nuclear shell-model calculations is introduced. In order to count the number of the eigen-values of the shell-model Hamiltonian matrix, we perform the contour integral of the matrix element of a resolvent. The shifted block Krylov subspace method enables us its efficient computation. Utilizing this method, the contamination of center-of-mass motion is clearly removed.
A modified calculation model for groundwater flowing to horizontal seepage wells
Indian Academy of Sciences (India)
Wei Wang; Peng Chen; Qingqing Zheng; Xinyu Zheng; Kunming Lu
2013-04-01
The simulation models for groundwater flowing to horizontal seepage wells proposed by Wang and Zhang (2007) are based on the theory of coupled seepage-pipe flow model which treats the well pipe as a highly permeable medium. However, the limitations of the existing model were found during applications. Specifically, a high-resolution grid is required to depict the complex structure of horizontal seepage wells; the permeability of the screen or wall material of radiating bores is usually neglected; and the irregularly distributed radiating bores cannot be accurately simulated. A modified calculation model of groundwater flowing to a horizontal seepage well is introduced in this paper. The exchange flow between well pipe and aquifer couples the turbulent flow inside the horizontal seepage well with laminar flow in the aquifer. The modified calculation model can reliably calculate the pumpage of a real horizontal seepage well. The characteristics of radiating bores, including the diameter, the permeability of screen material and irregular distribution of radiating bores, can be accurately depicted using the modified model that simulates the scenario in which several horizontal seepage wells work together.
The impact of MM5 and WRF meteorology over complex terrain on CHIMERE model calculations
Directory of Open Access Journals (Sweden)
A. de Meij
2009-01-01
Full Text Available The objective of this study is to evaluate the impact of meteorological input data on calculated gas and aerosol concentrations. We use two different meteorological models (MM5 and WRF together with the chemistry transport model CHIMERE. We focus on the Po valley area (Italy for January and June 2005.
Firstly we evaluate the meteorological parameters with observations. The analysis shows that the performance of both models is similar, however some small differences are still noticeable.
Secondly, we analyze the impact of using MM5 and WRF on calculated PM_{10} and O_{3} concentrations. In general CHIMERE/MM5 and CHIMERE/WRF underestimate the PM_{10} concentrations for January. The difference in PM_{10} concentrations for January between CHIMERE/MM5 and CHIMERE/WRF is around a factor 1.6 (PM_{10} higher for CHIMERE/MM5. This difference and the larger underestimation in PM_{10} concentrations by CHIMERE/WRF are related to the differences in heat fluxes and the resulting PBL heights calculated by WRF. In general the PBL height by WRF meteorology is a factor 2.8 higher at noon in January than calculated by MM5. This study showed that the difference in microphysics scheme has an impact on the profile of cloud liquid water (CLW calculated by the meteorological driver and therefore on the production of SO_{4} aerosol.
A sensitivity analysis shows that changing the Noah Land Surface Model (LSM for the 5-layer soil temperature model, the calculated monthly mean PM_{10} concentrations increase by 30%, due to the change in the heat fluxes and the resulting PBL heights.
For June, PM_{10} calculated concentrations by CHIMERE/MM5 and CHIMERE/WRF are similar and agree with the observations. Calculated O_{3} values for June are in general overestimated by a factor 1.3 by CHIMERE/MM5 and CHIMRE/WRF. The reason for this is that daytime NO_{2
}
Energy Technology Data Exchange (ETDEWEB)
1992-12-29
This volume documents model parameters chosen as of July 1992 that were used by the Performance Assessment Department of Sandia National Laboratories in its 1992 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Ranges and distributions for about 300 modeling parameters in the current secondary data base are presented in tables for the geologic and engineered barriers, global materials (e.g., fluid properties), and agents that act upon the WIPP disposal system such as climate variability and human-intrusion boreholes. The 49 parameters sampled in the 1992 Preliminary Performance Assessment are given special emphasis with tables and graphics that provide insight and sources of data for each parameter.
Model-based calculating tool for pollen-mediated gene flow frequencies in plants.
Lei, Wang; Bao-Rong, Lu
2016-12-30
The potential social-economic and environmental impacts caused by transgene flow from genetically engineered (GE) crops have stimulated worldwide biosafety concerns. To determine transgene flow frequencies resulted from pollination is the first critical step for assessing such impacts, in addition to the determination of transgene expression and fitness in crop-wild hybrid descendants. Two methods are commonly used to estimate pollen-mediated gene flow (PMGF) frequencies: field experimenting and mathematical modeling. Field experiments can provide relatively accurate results but are time/resource consuming. Modeling offers an effective complement for PMGF experimental assessment. However, many published models describe PMGF by mathematical equations and are practically not easy to use. To increase the application of PMGF modeling for the estimation of transgene flow, we established a tool to calculate PMGF frequencies based on a quasi-mechanistic PMGF model for wind-pollination species. This tool includes a calculating program displayed by an easy-operating interface. PMGF frequencies of different plant species can be quickly calculated under different environmental conditions by including a number of biological and wind speed parameters that can be measured in the fields/laboratories or obtained from published data. The tool is freely available in the public domain (http://ecology.fudan.edu.cn/userfiles/cn/files/Tool_Manual.zip). Case studies including rice, wheat, and maize demonstrated similar results between the calculated frequencies based on this tool and those from published PMGF data. This PMGF calculating tool will provide useful information for assessing and monitoring social-economic and environmental impacts caused by transgene flow from GE crops. This tool can also be applied to determine the isolation distances between GE and non-GE crops in a coexistence agro-ecosystem, and to ensure the purity of certified seeds by setting proper isolation distances
The role of convective model choice in calculating the climate impact of doubling CO2
Lindzen, R. S.; Hou, A. Y.; Farrell, B. F.
1982-01-01
The role of the parameterization of vertical convection in calculating the climate impact of doubling CO2 is assessed using both one-dimensional radiative-convective vertical models and in the latitude-dependent Hadley-baroclinic model of Lindzen and Farrell (1980). Both the conventional 6.5 K/km and the moist-adiabat adjustments are compared with a physically-based, cumulus-type parameterization. The model with parameterized cumulus convection has much less sensitivity than the 6.5 K/km adjustment model at low latitudes, a result that can be to some extent imitiated by the moist-adiabat adjustment model. However, when averaged over the globe, the use of the cumulus-type parameterization in a climate model reduces sensitivity only approximately 34% relative to models using 6.5 K/km convective adjustment. Interestingly, the use of the cumulus-type parameterization appears to eliminate the possibility of a runaway greenhouse.
Energy Technology Data Exchange (ETDEWEB)
Hermanson, Jan; Forssberg, Ola [Golder Associates AB, Stockholm (Sweden); Fox, Aaron; La Pointe, Paul [Golder Associates Inc., Redmond, WA (United States)
2005-10-15
The goal of this summary report is to document the data sources, software tools, experimental methods, assumptions, and model parameters in the discrete-fracture network (DFN) model for the local model volume in Laxemar, version 1.2. The model parameters presented herein are intended for use by other project modeling teams. Individual modeling teams may elect to simplify or use only a portion of the DFN model, depending on their needs. This model is not intended to be a flow model or a mechanical model; as such, only the geometrical characterization is presented. The derivations of the hydraulic or mechanical properties of the fractures or their subsurface connectivities are not within the scope of this report. This model represents analyses carried out on particular data sets. If additional data are obtained, or values for existing data are changed or excluded, the conclusions reached in this report, and the parameter values calculated, may change as well. The model volume is divided into two subareas; one located on the Simpevarp peninsula adjacent to the power plant (Simpevarp), and one further to the west (Laxemar). The DFN parameters described in this report were determined by analysis of data collected within the local model volume. As such, the final DFN model is only valid within this local model volume and the modeling subareas (Laxemar and Simpevarp) within.
Goorley, J T; Kiger, W S; Zamenhof, R G
2002-02-01
As clinical trials of Neutron Capture Therapy (NCT) are initiated in the U.S. and other countries, new treatment planning codes are being developed to calculate detailed dose distributions in patient-specific models. The thorough evaluation and comparison of treatment planning codes is a critical step toward the eventual standardization of dosimetry, which, in turn, is an essential element for the rational comparison of clinical results from different institutions. In this paper we report development of a reference suite of computational test problems for NCT dosimetry and discuss common issues encountered in these calculations to facilitate quantitative evaluations and comparisons of NCT treatment planning codes. Specifically, detailed depth-kerma rate curves were calculated using the Monte Carlo radiation transport code MCNP4B for four different representations of the modified Snyder head phantom, an analytic, multishell, ellipsoidal model, and voxel representations of this model with cubic voxel sizes of 16, 8, and 4 mm. Monoenergetic and monodirectional beams of 0.0253 eV, 1, 2, 10, 100, and 1000 keV neutrons, and 0.2, 0.5, 1, 2, 5, and 10 MeV photons were individually simulated to calculate kerma rates to a statistical uncertainty of neutron beam with a broad neutron spectrum, similar to epithermal beams currently used or proposed for NCT clinical trials, was computed for all models. The thermal neutron, fast neutron, and photon kerma rates calculated with the 4 and 8 mm voxel models were within 2% and 4%, respectively, of those calculated for the analytical model. The 16 mm voxel model produced unacceptably large discrepancies for all dose components. The effects from different kerma data sets and tissue compositions were evaluated. Updating the kerma data from ICRU 46 to ICRU 63 data produced less than 2% difference in kerma rate profiles. The depth-dose profile data, Monte Carlo code input, kerma factors, and model construction files are available
Preliminary Monte Carlo Results for the Three-Dimensional Holstein Model
Institute of Scientific and Technical Information of China (English)
吴焰立; 刘川; 罗强
2003-01-01
Monte Carlo simulations are used to study the three-dimensional Holstein model. The relationship between the band filling and the chemical potential is obtained for various phonon frequencies and temperatures. The energy of a single electron or a hole is also calculated as a function of the lattice momenta.
Anderson, Christine A; Whall, Ann L
2013-10-01
Opinion leaders are informal leaders who have the ability to influence others' decisions about adopting new products, practices or ideas. In the healthcare setting, the importance of translating new research evidence into practice has led to interest in understanding how opinion leaders could be used to speed this process. Despite continued interest, gaps in understanding opinion leadership remain. Agent-based models are computer models that have proven to be useful for representing dynamic and contextual phenomena such as opinion leadership. The purpose of this paper is to describe the work conducted in preparation for the development of an agent-based model of nursing opinion leadership. The aim of this phase of the model development project was to clarify basic assumptions about opinions, the individual attributes of opinion leaders and characteristics of the context in which they are effective. The process used to clarify these assumptions was the construction of a preliminary nursing opinion leader model, derived from philosophical theories about belief formation. © 2013 John Wiley & Sons Ltd.
Kudo, Takashi; Kushikata, Tetsuya; Kudo, Mihoko; Kudo, Tsuyoshi; Hirota, Kazuyoshi
2010-09-06
Neuropathic pain models are classified as central and peripheral pain models. Although various peripheral neuropathic pain models are established, central pain models are based only on spinal cord injury. DSP-4 is a competitive inhibitor of norepinephrine uptake that selectively degenerates the locus coeruleus (LC)-noradrenergic neurons projection to the cerebral cortex and hippocampus. In the present study, we have tested whether lesion of LC-noradrenergic neurons by ip DSP-4 (0, 10, 30, 50 mg/kg, n=7 each) could provide a new central neuropathic pain model in rats using a hot-plate and tail-flick tests. DSP-4 significantly reduced the hot-plate latency and norepinephrine contents especially in the coerulean regions. However, DSP-4 did not change tail-flick latency. There are significant correlations of the latency in the hot-plate test with norepinephrine contents in the cerebral cortex (r=0.432, p=0.022), the hippocampus (r=0.465, p=0.013) and the pons (r=0.400, p=0.035) but not with those in the hypothalamus and the spinal cord. As response to hot-plate and tail-flick implies supra-spinal process and spinal reflex, respectively, central neuropathic pain may be facilitated by DSP-4 depleting LC-noradrenergic neurons although the present data are preliminary.
Directory of Open Access Journals (Sweden)
B. Kravitz
2015-10-01
Full Text Available We present a suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP. This set of experiments, named GeoMIP6 (to be consistent with the Coupled Model Intercomparison Project Phase 6, builds on the previous GeoMIP project simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space. We discuss experiment designs, as well as the rationale for those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1 GeoMIP experiments. This is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.
Kravitz, B.; Robock, A.; Tilmes, S.; Boucher, O.; English, J. M.; Irvine, P. J.; Jones, A.; Lawrence, M. G.; MacCracken, M.; Muri, H.; Moore, J. C.; Niemeier, U.; Phipps, S. J.; Sillmann, J.; Storelvmo, T.; Wang, H.; Watanabe, S.
2015-10-01
We present a suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP). This set of experiments, named GeoMIP6 (to be consistent with the Coupled Model Intercomparison Project Phase 6), builds on the previous GeoMIP project simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space. We discuss experiment designs, as well as the rationale for those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1) GeoMIP experiments. This is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.
Fahrul Hassan, Mohd; Rahman, M. R. A.; Arifin, A. M. T.; Ismail, A. E.; Rasidi Ibrahim, M.; Zulafif Rahim, M.; Fauzi Ahmad, Md
2017-08-01
Product manufactured with short life cycle had only one major issue, it can lead to increasing volume of waste. Day by day, this untreated waste had consumed many landfill spaces, waiting for any possible alternatives. Lack of product recovery knowledge and recyclability features imprinted into product design are one of the main reason behind all this. Sustainable awareness aspect should not just be implied into people’s mind, but also onto product design. This paper presents a preliminary study on Kano model method in the conceptual design activities to improve product lifecycle. Kano model is a survey-type method, used to analyze and distinguished product qualities or features, also how the customers may have perceived them. Three important attributes of Kano model are performance, attractive and must-be. The proposed approach enables better understanding of customer requirements while providing a way for Kano model to be integrated into engineering design to improve product’s end-of-life. Further works will be continued to provide a better lifecycle option (increase percentage of reuse, remanufacture or recycle, whereby decrease percentage of waste) of a product using Kano model approach.
Multi-Loop Calculations of Anomalous Exponents in the Models of Critical Dynamics
Directory of Open Access Journals (Sweden)
Adzhemyan L. Ts.
2016-01-01
Full Text Available The Renormalization group method (RG is applied to the investigation of the E model of critical dynamics, which describes the transition from the normal to the superfluid phase in He4. The technique “Sector decomposition” with R’ operation is used for the calculation of the Feynman diagrams. The RG functions, critical exponents and critical dynamical exponent z, which determines the growth of the relaxation time near the critical point, have been calculated in the two-loop approximation in the framework of ε-expansion. The relevance of a fixed point for helium, where the dynamic scaling is weakly violated, is briefly discussed.
Calculation of accurate small angle X-ray scattering curves from coarse-grained protein models
DEFF Research Database (Denmark)
Stovgaard, Kasper; Andreetta, Christian; Ferkinghoff-Borg, Jesper
2010-01-01
the computationally costly iteration over all atoms. We estimated the form factors using generated data from a set of high quality protein structures. No ad hoc scaling or correction factors are applied in the calculation of the curves. Two coarse-grained representations of protein structure were investigated; two...... CRYSOL, which requires full atomic detail. Our method was also comparable to CRYSOL in recognizing native structures among native-like decoys. As a proof-of-concept, we combined the coarse-grained Debye calculation with a previously described probabilistic model of protein structure, Torus...
Energy Technology Data Exchange (ETDEWEB)
Cermak, V. (Geophys. Inst., Prague)
1974-01-01
The first draft of the heat flow map of Central and Eastern Europe demonstrates the general heat flow pattern in the Carpathians. The Pannonian Basin, located between the Carpathians and Dinarides, is a zone of anomalous heat flow (greater than 2.0 HFU). The geothermal activity decreases rapidly to 1.3-1.5 HFU in the Carpathian arc. A preliminary map of crustal thickness, based on the results of gravity and seismic surveys, shows that the Mohorovicic discontinuity lies at a shallow depth below the Basin (24-26 km) and is deeper below the Carpathians (50 km). With some basic assumptions concerning the distribution of thermal conductivity and heat production applied, deep temperatures along a traverse crossing the Carpathian arc were calculated. The Moho temperature of 700/sup 0/C beneath the peri-Pieninian Lineament may increase to 800-1000/sup 0/C beneath the Pannonian Basin, and regional heat flow differences may reach 1.0 HFU. This type of variation in the energy input from the upper mantle is important in interpreting the tectonic evolution of the entire area.
A brief look at model-based dose calculation principles, practicalities, and promise.
Sloboda, Ron S; Morrison, Hali; Cawston-Grant, Brie; Menon, Geetha V
2017-02-01
Model-based dose calculation algorithms (MBDCAs) have recently emerged as potential successors to the highly practical, but sometimes inaccurate TG-43 formalism for brachytherapy treatment planning. So named for their capacity to more accurately calculate dose deposition in a patient using information from medical images, these approaches to solve the linear Boltzmann radiation transport equation include point kernel superposition, the discrete ordinates method, and Monte Carlo simulation. In this overview, we describe three MBDCAs that are commercially available at the present time, and identify guidance from professional societies and the broader peer-reviewed literature intended to facilitate their safe and appropriate use. We also highlight several important considerations to keep in mind when introducing an MBDCA into clinical practice, and look briefly at early applications reported in the literature and selected from our own ongoing work. The enhanced dose calculation accuracy offered by a MBDCA comes at the additional cost of modelling the geometry and material composition of the patient in treatment position (as determined from imaging), and the treatment applicator (as characterized by the vendor). The adequacy of these inputs and of the radiation source model, which needs to be assessed for each treatment site, treatment technique, and radiation source type, determines the accuracy of the resultant dose calculations. Although new challenges associated with their familiarization, commissioning, clinical implementation, and quality assurance exist, MBDCAs clearly afford an opportunity to improve brachytherapy practice, particularly for low-energy sources.
A brief look at model-based dose calculation principles, practicalities, and promise
Directory of Open Access Journals (Sweden)
Ron S. Sloboda
2017-02-01
Full Text Available Model-based dose calculation algorithms (MBDCAs have recently emerged as potential successors to the highly practical, but sometimes inaccurate TG-43 formalism for brachytherapy treatment planning. So named for their capacity to more accurately calculate dose deposition in a patient using information from medical images, these approaches to solve the linear Boltzmann radiation transport equation include point kernel superposition, the discrete ordinates method, and Monte Carlo simulation. In this overview, we describe three MBDCAs that are commercially available at the present time, and identify guidance from professional societies and the broader peer-reviewed literature intended to facilitate their safe and appropriate use. We also highlight several important considerations to keep in mind when introducing an MBDCA into clinical practice, and look briefly at early applications reported in the literature and selected from our own ongoing work. The enhanced dose calculation accuracy offered by a MBDCA comes at the additional cost of modelling the geometry and material composition of the patient in treatment position (as determined from imaging, and the treatment applicator (as characterized by the vendor. The adequacy of these inputs and of the radiation source model, which needs to be assessed for each treatment site, treatment technique, and radiation source type, determines the accuracy of the resultant dose calculations. Although new challenges associated with their familiarization, commissioning, clinical implementation, and quality assurance exist, MBDCAs clearly afford an opportunity to improve brachytherapy practice, particularly for low-energy sources.
A Combination of Preliminary Electroweak Measurements and Constraints on the Standard Model
Energy Technology Data Exchange (ETDEWEB)
Su, Dong
2003-05-15
This note presents a combination of published and preliminary electroweak results from the four LEP collaborations and the SLD collaboration which were prepared for the 1997 summer conferences. Averages are derived for hadronic and leptonic cross-sections, the leptonic forward-backward asymmetries, the {tau} polarisation asymmetries, the b{bar b} and c{bar c} partial widths and forward-backward asymmetries and the q{bar q} charge asymmetry. The major changes with respect to results presented last year are updated results of A{sub LR} from SLD, and the inclusion of the first direct measurements of the W mass and triple-gauge-boson couplings performed at LEP. The results are compared with precise electroweak measurements from other experiments. The parameters of the Standard Model are evaluated, first using the combined LEP electroweak measurements, and then using the full set of electroweak results.
Cost-based optimization of a nuclear reactor core design: a preliminary model
Energy Technology Data Exchange (ETDEWEB)
Sacco, Wagner F.; Alves Filho, Hermes [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Inst. Politecnico. Dept. de Modelagem Computacional]. E-mails: wfsacco@iprj.uerj.br; halves@iprj.uerj.br; Pereira, Claudio M.N.A. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil). Div. de Reatores]. E-mail: cmnap@ien.gov.br
2007-07-01
A new formulation of a nuclear core design optimization problem is introduced in this article. Originally, the optimization problem consisted in adjusting several reactor cell parameters, such as dimensions, enrichment and materials, in order to minimize the radial power peaking factor in a three-enrichment zone reactor, considering restrictions on the average thermal flux, criticality and sub-moderation. Here, we address the same problem using the minimization of the fuel and cladding materials costs as the objective function, and the radial power peaking factor as an operational constraint. This cost-based optimization problem is attacked by two metaheuristics, the standard genetic algorithm (SGA), and a recently introduced Metropolis algorithm called the Particle Collision Algorithm (PCA). The two algorithms are submitted to the same computational effort and their results are compared. As the formulation presented is preliminary, more elaborate models are also discussed (author)
A Combination of Preliminary Electroweak Measurements and Constraints on the Standard Model, 2000
CERN. Geneva
2000-01-01
This note presents a combination of published and preliminary electroweak results from the four LEP collaborations and the SLD collaboration which were prepared for the 1999 summer conferences. Averages are derived for hadronic and leptonic cross sections, the leptonic forward-backward asymmetries, the $\\tau$ polarisation asymmetries, the $\\bb$ and $\\cc$ partial widths and forward-backward asymmetries and the $\\qq$ charge asymmetry. The major changes with respect to results presented in summer 1998 are updates to the lineshape, W mass and triple-gauge-boson couplings from LEP, and $\\cAb$ and $\\cAc$ from SLD. The results are compared with precise electroweak measurements from other experiments. A significant update here are new W mass measurements from CDF and D\\O. The parameters of the Standard Model are evaluated, first using the combined LEP electroweak measurements, and then using the full set of electroweak results.
Wang, Junmei; Hou, Tingjun
2012-05-25
It is of great interest in modern drug design to accurately calculate the free energies of protein-ligand or nucleic acid-ligand binding. MM-PBSA (molecular mechanics Poisson-Boltzmann surface area) and MM-GBSA (molecular mechanics generalized Born surface area) have gained popularity in this field. For both methods, the conformational entropy, which is usually calculated through normal-mode analysis (NMA), is needed to calculate the absolute binding free energies. Unfortunately, NMA is computationally demanding and becomes a bottleneck of the MM-PB/GBSA-NMA methods. In this work, we have developed a fast approach to estimate the conformational entropy based upon solvent accessible surface area calculations. In our approach, the conformational entropy of a molecule, S, can be obtained by summing up the contributions of all atoms, no matter they are buried or exposed. Each atom has two types of surface areas, solvent accessible surface area (SAS) and buried SAS (BSAS). The two types of surface areas are weighted to estimate the contribution of an atom to S. Atoms having the same atom type share the same weight and a general parameter k is applied to balance the contributions of the two types of surface areas. This entropy model was parametrized using a large set of small molecules for which their conformational entropies were calculated at the B3LYP/6-31G* level taking the solvent effect into account. The weighted solvent accessible surface area (WSAS) model was extensively evaluated in three tests. For convenience, TS values, the product of temperature T and conformational entropy S, were calculated in those tests. T was always set to 298.15 K through the text. First of all, good correlations were achieved between WSAS TS and NMA TS for 44 protein or nucleic acid systems sampled with molecular dynamics simulations (10 snapshots were collected for postentropy calculations): the mean correlation coefficient squares (R²) was 0.56. As to the 20 complexes, the TS
Accelerated complete-linearization method for calculating NLTE model stellar atmospheres
Hubeny, I.; Lanz, T.
1992-01-01
Two approaches to accelerating the method of complete linearization for calculating NLTE model stellar atmospheres are suggested. The first one, the so-called Kantorovich variant of the Newton-Raphson method, consists of keeping the Jacobi matrix of the system fixed, which allows us to calculate the costly matrix inversions only a few times and then keep them fixed during the subsequent computations. The second method is an application of the Ng acceleration. Both methods are extremely easy to implement with any model atmosphere code based on complete linearization. It is demonstrated that both methods, and especially their combination, yield a rapidly and globally convergent algorithm, which takes 2 to 5 times less computer time, depending on the model at hand and the required accuracy, than the ordinary complete linearization. Generally, the time gain is more significant for more complicated models. The methods were tested for a broad range of atmospheric parameters, and in all cases they exhibited similar behavior. Ng acceleration applied on the Kantorovich variant thus offers a significant improvement of the standard complete-linearization method, and may now be used for calculating relatively involved NLTE model stellar atmospheres.
Voxel2MCNP: software for handling voxel models for Monte Carlo radiation transport calculations.
Hegenbart, Lars; Pölz, Stefan; Benzler, Andreas; Urban, Manfred
2012-02-01
Voxel2MCNP is a program that sets up radiation protection scenarios with voxel models and generates corresponding input files for the Monte Carlo code MCNPX. Its technology is based on object-oriented programming, and the development is platform-independent. It has a user-friendly graphical interface including a two- and three-dimensional viewer. A row of equipment models is implemented in the program. Various voxel model file formats are supported. Applications include calculation of counting efficiency of in vivo measurement scenarios and calculation of dose coefficients for internal and external radiation scenarios. Moreover, anthropometric parameters of voxel models, for instance chest wall thickness, can be determined. Voxel2MCNP offers several methods for voxel model manipulations including image registration techniques. The authors demonstrate the validity of the program results and provide references for previous successful implementations. The authors illustrate the reliability of calculated dose conversion factors and specific absorbed fractions. Voxel2MCNP is used on a regular basis to generate virtual radiation protection scenarios at Karlsruhe Institute of Technology while further improvements and developments are ongoing.
Experience at Los Alamos with use of the optical model for applied nuclear data calculations
Energy Technology Data Exchange (ETDEWEB)
Young, P.G.
1994-10-01
While many nuclear models are important in calculations of nuclear data, the optical model usually provides the basic underpinning of analyses directed at data for applications. An overview is given here of experience in the Nuclear Theory and Applications Group at Los Alamos National Laboratory in the use of the optical model for calculations of nuclear cross section data for applied purposes. We consider the direct utilization of total, elastic, and reaction cross sections for neutrons, protons, deuterons, tritons, {sup 3}He and alpha particles in files of evaluated nuclear data covering the energy range of 0 to 200 MeV, as well as transmission coefficients for reaction theory calculations and neutron and proton wave functions direct-reaction and Feshbach-Kerman-Koonin analyses. Optical model codes such as SCAT and ECIS and the reaction theory codes COMNUC, GNASH FKK-GNASH, and DWUCK have primarily been used in our analyses. A summary of optical model parameterizations from past analyses at Los Alamos will be given, including detailed tabulations of the parameters for a selection of nuclei.
X-ray spectra of high temperature tungsten plasma calculated with collisional radiative model
Institute of Scientific and Technical Information of China (English)
Wang Jun; Zhang Hong; Cheng Xin-Lu
2013-01-01
Tungsten is regarded as an important candidate of plasma facing material in international thermonuclear experimental reactor (ITER),so the determination and modeling of spectra of tungsten plasma,especially the spectra at high temperature were intensely focused on recently.In this work,using the atomic structure code of Cowan,a collisional radiative model (CRM) based on the spin-orbit-split-arrays is developed.Based on this model,the charge state distribution of tungsten ions is determined and the soft X-ray spectra from high charged ions of tungsten at different temperatures are calculated.The results show that both the average ionization charge and line positions are well agreed with others calculations and measurements with discrepancies of less than 0.63％ and 1.26％,respectively.The spectra at higher temperatures are also reported and the relationship between ion abundance and temperature is predicted in this work.
[A 3D FEM model for calculation of electromagnetic fields in transmagnetic stimulation].
Seilwinder, J; Kammer, T; Andrä, W; Bellemann, M E
2002-01-01
We developed a realistic finite elements method (FEM) model of the brain for the calculation of electromagnetic fields in transcranial magnetic stimulation (TMS). A focal butterfly stimulation coil was X-rayed, parameterized, and modeled. The magnetic field components of the TMS coil were calculated and compared for validation to pointwise measurements of the magnetic fields with a Hall sensor. We found a mean deviation of 7.4% at an axial distance of 20 mm to the coil. A 3D brain model with the biological tissues of white and gray matter, bone, and cerebrospinal fluid was developed. At a current sweep of 1000 A in 120 microseconds, the maximum induced current density in gray matter was 177 mA/m2 and the strongest electric field gradient covered an area of 40 mm x 53 mm.
Energy Technology Data Exchange (ETDEWEB)
Feldman, J.L.; Broughton, J.Q. (Complex Systems Theory Branch, Naval Research Laboratory, Washington, D.C. 20375-5000 (US)); Wooten, F. (Department of Applied Science, University of California at Davis/Livermore, Livermore, California 94550 (US))
1991-01-15
Calculations, based on the Stillinger-Weber (SW) interatomic-potential model and the method of long waves, are presented for the elastic properties of amorphous Si ({ital a}-Si) and for pressure derivatives of the elastic constants of crystalline Si. Several models of {ital a}-Si, relaxed on the basis of the SW potential, are considered, and the external stresses that are associated with these models are evaluated using the Born-Huang relations. The elastic constants appear to obey the isotropy conditions to within a reasonable accuracy and are also consistent with other predictions based on the SW potential at finite temperature obtained by Kluge and Ray. Estimates of the pressure dependence of the elastic constants, Debye temperature, and Grueeisen parameter for {ital a}-Si are also provided on the basis of these calculations.
Analytical model for release calculations in solid thin-foils ISOL targets
Energy Technology Data Exchange (ETDEWEB)
Egoriti, L. [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); Politecnico di Milano, Department of Energy, CeSNEF-Nuclear Engineering Division, Via Ponzio, 34/3, 20133 Milano (Italy); Boeckx, S. [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); ICTEAM Inst., Univ. Catholique de Louvain, Louvain-la-Neuve (Belgium); Ghys, L. [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); Houngbo, D., E-mail: donald.houngbo@sckcen.be [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); Department of Flow, Heat and Combustion Mechanics, Gent University (UGent), St.-Pietersnieuwstraat 41, B-9000 Gent (Belgium); Popescu, L. [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium)
2016-10-01
A detailed analytical model has been developed to simulate isotope-release curves from thin-foils ISOL targets. It involves the separate modeling of diffusion and effusion inside the target. The former has been modeled using both first and second Fick's law. The latter, effusion from the surface of the target material to the end of the ionizer, was simulated with the Monte Carlo code MolFlow+. The calculated delay-time distribution for this process was then fitted using a double-exponential function. The release curve obtained from the convolution of diffusion and effusion shows good agreement with experimental data from two different target geometries used at ISOLDE. Moreover, the experimental yields are well reproduced when combining the release fraction with calculated in-target production.
Analytical model for release calculations in solid thin-foils ISOL targets
Egoriti, L.; Boeckx, S.; Ghys, L.; Houngbo, D.; Popescu, L.
2016-10-01
A detailed analytical model has been developed to simulate isotope-release curves from thin-foils ISOL targets. It involves the separate modeling of diffusion and effusion inside the target. The former has been modeled using both first and second Fick's law. The latter, effusion from the surface of the target material to the end of the ionizer, was simulated with the Monte Carlo code MolFlow+. The calculated delay-time distribution for this process was then fitted using a double-exponential function. The release curve obtained from the convolution of diffusion and effusion shows good agreement with experimental data from two different target geometries used at ISOLDE. Moreover, the experimental yields are well reproduced when combining the release fraction with calculated in-target production.
Analytical model for release calculations in solid thin-foils ISOL targets
Egoriti, Luca; Ghys, Lars; Houngbo, Donald; Popescu, Lucia
2016-01-01
A detailed analytical model has been developed to simulate isotope-release curves from thin-foils ISOL targets. It involves the separate modelling of diffusion and effusion inside the target. The former has been modelled using both first and second Fick's law. The latter, effusion from the surface of the target material to the end of the ionizer, was simulated with the Monte Carlo code MolFlow+. The calculated delay-time distribution for this process was then fitted using a double-exponential function. The release curve obtained from the convolution of diffusion and effusion shows good agreement with experimental data from two different target geometries used at ISOLDE. Moreover, the experimental yields are well reproduced when combining the release fraction with calculated in-target production.
A model for calculating a.c. losses in multistage superconducting cables
Schild, T.; Ciazynski, D.
Superconducting magnets in tokamaks for fusion experiments are subjected to fast variations in magnetic field. As the high current conductors used in these magnets are made of multistage cables, these variations induce interstrand coupling currents that create losses. These losses are usually characterized by the so-called time constant of the conductor. A model is given to calculate this time constant. Working formulas are also proposed to calculate the current induced in the different cabling stages. This model takes into account the strand characteristics and the detailed cabling pattern. Using it, a method is also given to deduce the time constant from resistive measurements. The influence of the resistive barrier (chrome plating, CuNi shell, outer bronze matrix) is pointed out. Finally, this model is applied to a conductor that is foreseen for the toroidal coils of the International Thermonuclear Experimental Reactor (ITER).
Tight-binding model for carbon nanotubes from ab initio calculations.
Correa, J D; da Silva, Antônio J R; Pacheco, M
2010-07-14
Here we present a parametrized tight-binding (TB) model to calculate the band structure of single-wall carbon nanotubes (SWNTs). On the basis of ab initio calculations we fit the band structure of nanotubes of different radii with results obtained with an orthogonal TB model to third neighbors, which includes the effects of orbital hybridization by means of a reduced set of parameters. The functional form for the dependence of these parameters on the radius of the tubes can be used to interpolate appropriate TB parameters for different SWNTs and to study the effects of curvature on their electronic properties. Additionally, we have shown that the model gives an appropriate description of the optical spectra of SWNTs, which can be useful for a proper assignation of SWNTs' specific chirality from optical absorption experiments.
Deterministic Partial Differential Equation Model for Dose Calculation in Electron Radiotherapy
Duclous, Roland; Frank, Martin
2009-01-01
Treatment with high energy ionizing radiation is one of the main methods in modern cancer therapy that is in clinical use. During the last decades, two main approaches to dose calculation were used, Monte Carlo simulations and semi-empirical models based on Fermi-Eyges theory. A third way to dose calculation has only recently attracted attention in the medical physics community. This approach is based on the deterministic kinetic equations of radiative transfer. Starting from these, we derive a macroscopic partial differential equation model for electron transport in tissue. This model involves an angular closure in the phase space. It is exact for the free-streaming and the isotropic regime. We solve it numerically by a newly developed HLLC scheme based on [BerCharDub], that exactly preserves key properties of the analytical solution on the discrete level. Several numerical results for test cases from the medical physics literature are presented.
Generic model for calculating carbon footprint of milk using four different LCA modelling approaches
DEFF Research Database (Denmark)
Dalgaard, Randi; Schmidt, Jannick Højrup; Flysjö, Anna
2014-01-01
The aim of the study is to develop a tool, which can be used for calculation of carbon footprint (using a life cycle assessment (LCA) approach) of milk both at a farm level and at a national level. The functional unit is ‘1 kg energy corrected milk (ECM) at farm gate’ and the applied methodology ...
Performance of a Predictive Model for Calculating Ascent Time to a Target Temperature
Directory of Open Access Journals (Sweden)
Jin Woo Moon
2016-12-01
Full Text Available The aim of this study was to develop an artificial neural network (ANN prediction model for controlling building heating systems. This model was used to calculate the ascent time of indoor temperature from the setback period (when a building was not occupied to a target setpoint temperature (when a building was occupied. The calculated ascent time was applied to determine the proper moment to start increasing the temperature from the setback temperature to reach the target temperature at an appropriate time. Three major steps were conducted: (1 model development; (2 model optimization; and (3 performance evaluation. Two software programs—Matrix Laboratory (MATLAB and Transient Systems Simulation (TRNSYS—were used for model development, performance tests, and numerical simulation methods. Correlation analysis between input variables and the output variable of the ANN model revealed that two input variables (current indoor air temperature and temperature difference from the target setpoint temperature, presented relatively strong relationships with the ascent time to the target setpoint temperature. These two variables were used as input neurons. Analyzing the difference between the simulated and predicted values from the ANN model provided the optimal number of hidden neurons (9, hidden layers (3, moment (0.9, and learning rate (0.9. At the study’s conclusion, the optimized model proved its prediction accuracy with acceptable errors.
Visible calculation of mining index based on stope 3D surveying and block modeling
Institute of Scientific and Technical Information of China (English)
Liu Xiaoming; Luo Zhouquan; Yang Biao; Lu Guang; Cao Shengxiang; Jiang Xinjian
2012-01-01
Aimed at the CMS laser scanning theory and characteristic,a combined actual situation of stope N4-5 of Fankou Lead-Zinc Mine and complementary monitoring of the stope were carried out by carefully choosing two measuring points.The cavity 3D visible model was created by large-scale mining industry software Surpac after changing the measured data.The stope mine design model,bottom structural model and backfill model of the south and north sides of the stope N4-5 were established according to the stope design data.On this basis,the stope block model was established,and then block attribute was estimated.The amount the ore remains,mullock,backfill and total mined ore were calculated through the solid model restrains.Finally,the stope mining dilution rate and loss rate reached 8.2％and 1.47％,respectively.The practice indicates that the mining index visible calculation method based on cavity 3D monitoring and stope block modeling can make up the deficiency of adopting the solid model to directly carry out the Boolean operation.The stope mining indexes obtained by this method are accurate and reliable,and can be used to guide the actual production management and estimate the mining quality.
Numerical Calculations of WR-40 Boiler Based on its Zero-Dimensional Model
Directory of Open Access Journals (Sweden)
Hernik Bartłomiej
2014-06-01
Full Text Available Generally, the temperature of flue gases at the furnace outlet is not measured. Therefore, a special computation procedure is needed to determine it. This paper presents a method for coordination of the numerical model of a pulverised fuel boiler furnace chamber with the measuring data in a situation when CFD calculations are made in regard to the furnace only. This paper recommends the use of the classical 0-dimensional balance model of a boiler, based on the use of measuring data. The average temperature of flue gases at the furnace outlet tk" obtained using the model may be considered as highly reliable. The numerical model has to show the same value of tk" . This paper presents calculations for WR-40 boiler. The CFD model was matched to the 0-dimensional tk" value by means of a selection of the furnace wall emissivity. As a result of CFD modelling, the flue gas temperature and the concentration of CO, CO2, O2 and NOx were obtained at the furnace chamber outlet. The results of numerical modelling of boiler combustion based on volumetric reactions and using the Finite-Rate/Eddy-Dissipation Model are presented.
Lengers, Bernd; Schiefler, Inga; Büscher, Wolfgang
2013-12-01
The overall measurement of farm level greenhouse gas (GHG) emissions in dairy production is not feasible, from either an engineering or administrative point of view. Instead, computational model systems are used to generate emission inventories, demanding a validation by measurement data. This paper tests the GHG calculation of the dairy farm-level optimization model DAIRYDYN, including methane (CH₄) from enteric fermentation and managed manure. The model involves four emission calculation procedures (indicators), differing in the aggregation level of relevant input variables. The corresponding emission factors used by the indicators range from default per cow (activity level) emissions up to emission factors based on feed intake, manure amount, and milk production intensity. For validation of the CH₄ accounting of the model, 1-year CH₄ measurements of an experimental free-stall dairy farm in Germany are compared to model simulation results. An advantage of this interdisciplinary study is given by the correspondence of the model parameterization and simulation horizon with the experimental farm's characteristics and measurement period. The results clarify that modeled emission inventories (2,898, 4,637, 4,247, and 3,600 kg CO₂-eq. cow(-1) year(-1)) lead to more or less good approximations of online measurements (average 3,845 kg CO₂-eq. cow(-1) year(-1) (±275 owing to manure management)) depending on the indicator utilized. The more farm-specific characteristics are used by the GHG indicator; the lower is the bias of the modeled emissions. Results underline that an accurate emission calculation procedure should capture differences in energy intake, owing to milk production intensity as well as manure storage time. Despite the differences between indicator estimates, the deviation of modeled GHGs using detailed indicators in DAIRYDYN from on-farm measurements is relatively low (between -6.4% and 10.5%), compared with findings from the literature.
Tsunami hazard assessment at Port Alberni, BC, Canada: preliminary model results
Grilli, S. T.; Insua, T. L.; Grilli, A. R.; Douglas, K. L.; Shelby, M. R.; Wang, K.; Gao, D.
2016-12-01
Located in the heart of Vancouver Island, BC, Port Alberni has a well-known history of tsunamis. Many of the Nuu-Chah-Nulth First Nations share oral stories about a strong fight between a thunderbird and a whale that caused big waves in a winter night, a story that is compatible with the recently recognized great Cascadia tsunami in January, 1700. Port Alberni, with a total population of approximately 20,000 people, lies beside the Somass River, at the very end of Barkley Sound Inlet. The narrow canal connecting this town to the Pacific Ocean runs for more than 64 km ( 40 miles) between steep mountains, providing an ideal setting for the amplification of tsunami waves through funnelling effects. The devastating effects of tsunamis are still fresh in residents' memories from the impact of the 1964 Alaska tsunami that caused serious damage to the city. In June 2016, Emergency Management BC ran a coastal exercise in Port Alberni, simulating the response to an earthquake and a tsunami. During three days, the emergency teams in the City of Port Alberni practiced and learned from the experience. Ocean Networks Canada contributed to this exercise with the development of preliminary simulations of tsunami impact on the city from a buried rupture of the Cascadia Subduction Zone, including the Explorer segment. Wave propagation was simulated with the long-wave model FUNWAVE-TVD. Preliminary results indicate a strong amplification of tsunami waves in the Port Alberni area. The inundation zone in Port Alberni had a footprint similar to that of the 1700 Cascadia and 1964 Alaska tsunamis, inundating the area surrounding the Somass river and preferentially following the Kitsuksis and Roger Creek river margins into the city. Several other tsunami source scenarios, including splay faulting and trench-breaching ruptures are currently being modeled for the city of Port Alberni following a similar approach. These results will be presented at the conference.
Cross, A. J.; Prior, D. J.; Ellis, S. M.
2012-12-01
It is widely accepted that changes in stress and grain size can induce a switch between grain-size insensitive (GSI) and sensitive (GSS) creep mechanisms. Under steady-state conditions, grains evolve to an equilibrium size in the boundary region between GSS and GSI, described by the paleopiezometer for a given material. Under these conditions, significant rheological weakening is not expected, as grain size reduction processes are balanced by grain growth processes. However, it has been shown that the stress field surrounding faults varies through the seismic cycle, with both rapid loading and unloading of stress possible in the co- and post-seismic stages. We propose that these changes in stress in the region of the brittle-ductile transition zone may be sufficient to force a deviation from the GSI-GSS boundary and thereby cause a change in grain size and creep mechanism prior to system re-equilibration. Here we present preliminary findings from numerical modelling of stress and grain size changes in response to loading of mechanical inhomogeneities. Our results are attained using a grain-size evolution (GSE) subroutine incorporated into the SULEC finite-element code developed by Susan Ellis and Susanne Buiter, which utilises an iterative approach of solving for spatial and temporal changes in differential stress, grain size and active creep mechanism. Preliminary models demonstrate that stress changes in response to the opening of a fracture in a flowing medium can be significant enough to cause a switch from GSI to GSS creep. These results are significant in the context of understanding spatial variations and feedback between stress, grain size and deformation mechanisms through the seismic cycle.
The impact of nuclear mass models on r-process nucleosynthesis network calculations
Vaughan, Kelly
2002-10-01
An insight into understanding various nucleosynthesis processes is via modelling of the process with network calculations. My project focus is r-process network calculations where the r-process is nucleosynthesis via rapid neutron capture thought to take place in high entropy supernova bubbles. One of the main uncertainties of the simulations is the Nuclear Physics input. My project investigates the role that nuclear masses play in the resulting abundances. The code tecode, involves rapid (n,γ) capture reactions in competition with photodisintegration and β decay onto seed nuclei. In order to fully analyze the effects of nuclear mass models on the relative isotopic abundances, calculations were done from the network code, keeping the initial environmental parameters constant throughout. The supernova model investigated by Qian et al (1996) in which two r-processes, of high and low frequency with seed nucleus ^90Se and of fixed luminosity (fracL_ν_e(0)r_7(0)^2 ˜= 8.77), contribute to the nucleosynthesis of the heavier elements. These two r-processes, however, do not contribute equally to the total abundance observed. The total isotopic abundance produced from both events was therefore calculated using equation refabund. Y(H+L) = fracY(H)+fY(L)f+1 applicability of the P-Scheme in relation to the other mass models to the r-process network calculations. 02 Pscheme Aprahamian,A., Gadala-Maria,A. & Cuka,N. 1996, Revista Mexicana de Fisica,42,1 code Surman,R. & Engel,J. 1998, Phys.Rev. C,54,4 thebibliography
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
It is difficult to identify the source(s) of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios of different biomarkers show that the relative contribution changes are non-linear when two oils with different concentrations of biomarkers mix with each other. This may result in an incorrect conclusion if ratios of biomarkers and a simple binary linear equation are used to calculate the contribution proportion of each end-member to the mixed oil. The changes of biomarker ratios with the mixing proportion of end-member oils in the trinal mixing model are more complex than in the binary mixing model. When four or more oils mix, the contribution proportion of each end-member oil to the mixed oil cannot be calculated using biomarker ratios and a simple formula. Artificial mixing experiments on typical oils reveal that the absolute concentrations of biomarkers in the mixed oil cause a linear change with mixing proportion of each end-member. Mathematical inferences verify such linear changes. Some of the mathematical calculation methods using the absolute concentrations or ratios of biomarkers to quantitatively determine the proportion of each end-member in the mixed oils are deduced from the results of artificial experiments and by theoretical inference. Ratio of two biomarker compounds changes as a hyperbola with the mixing proportion in the binary mixing model,as a hyperboloid in the trinal mixing model, and as a hypersurface when mixing more than three endmembers. The mixing proportion of each end-member can be quantitatively determined with these mathematical models, using the absolute concentrations and the ratios of biomarkers. The mathematical calculation model is more economical, convenient, accurate and reliable than conventional artificial mixing methods.
Corresponding-States and Parachor Models for the Calculation of Interfacial Tensions
DEFF Research Database (Denmark)
Zuo, You-Xiang; Stenby, Erling Halfdan
1997-01-01
A generalized corresponding-states model based on two reference fluids and a parachor correlation were developed for the prediction of interfacial tensions for non-polar and weakly polar pure fluids and mixtures. Pure methane and n-octane were chosen as reference fluids of the corresponding......-states model. The two models were tested on 86 pure substances, more than 30 binary and multicomponent mixtures, 11 naphtha reformate cuts, 6 petroleum cuts and 2 North Sea oil mixtures. The calculated results were found to be in good agreement with experimental data.Keywords: corresponding-states, parachor...
CALCULATION OF THERMAL AND SALINE TURBULENT FLOW BY k-ε MODEL
Institute of Scientific and Technical Information of China (English)
Hu Zhen-hong; Shen Yong-ming; Zheng Yong-hong; Liu Cai-guang
2003-01-01
Based on the N-S equation, taking the character of thermal and saline stratified flow into account, and considering the effects of buoyancy on turbulence, the k-ε model of thermal and saline stratified flow is established.Density stratified flow with both the vertical temperature gradient and the vertical salinity gradient is simulated numerically, in which turbulent terms are calculated by the k-ε turbulent model.The distributions of velocity, temperature and salinity are given in this paper.The feature of stratification and turbulence is described correctly by the model.The computational results agree well with the experimental data.
Calculation and Modeling of EMI from Integrated Circuits inside High-Speed Network Devices
Directory of Open Access Journals (Sweden)
S. K. Goudos
2006-12-01
Full Text Available This work presents a numerical approach to the modeling of Electromagnetic Interference (EMI from the emissions of ICs and PCBs inside rectangular metallic enclosures of network devices. The ICs are modeled as small magnetic and electric dipoles. Their interaction with the enclosures is studied with the dyadic Green's functions. Several calculation examples of surface current density on the metallic walls are given due to dipoles parallel to all directions. A Probabilistic Model is created from magnetic probe measurements in various types of router devices. Monte Carlo simulation is applied in order to perform a worst-case analysis. The applications of the above approach in PCB design are discussed.
A set of molecular models based on quantum mechanical ab initio calculations and thermodynamic data
Eckl, Bernhard; Hasse, Hans
2009-01-01
A parameterization strategy for molecular models on the basis of force fields is proposed, which allows a rapid development of models for small molecules by using results from quantum mechanical (QM) ab initio calculations and thermodynamic data. The geometry of the molecular models is specified according to the atom positions determined by QM energy minimization. The electrostatic interactions are modeled by reducing the electron density distribution to point dipoles and point quadrupoles located in the center of mass of the molecules. Dispersive and repulsive interactions are described by Lennard-Jones sites, for which the parameters are iteratively optimized to experimental vapor-liquid equilibrium (VLE) data, i.e. vapor pressure, saturated liquid density, and enthalpy of vaporization of the considered substance. The proposed modeling strategy was applied to a sample set of ten molecules from different substance classes. New molecular models are presented for iso-butane, cyclohexane, formaldehyde, dimethyl...
Calculated flame temperature (CFT) modeling of fuel mixture lower flammability limits.
Zhao, Fuman; Rogers, William J; Mannan, M Sam
2010-02-15
Heat loss can affect experimental flammability limits, and it becomes indispensable to quantify flammability limits when apparatus quenching effect becomes significant. In this research, the lower flammability limits of binary hydrocarbon mixtures are predicted using calculated flame temperature (CFT) modeling, which is based on the principle of energy conservation. Specifically, the hydrocarbon mixture lower flammability limit is quantitatively correlated to its final flame temperature at non-adiabatic conditions. The modeling predictions are compared with experimental observations to verify the validity of CFT modeling, and the minor deviations between them indicated that CFT modeling can represent experimental measurements very well. Moreover, the CFT modeling results and Le Chatelier's Law predictions are also compared, and the agreement between them indicates that CFT modeling provides a theoretical justification for the Le Chatelier's Law.
Calculation of Energy Spectrum of 12C Isotope by Relativistic Cluster model
Roshanbakht, Nafiseh
2016-01-01
In this paper, we have calculated the energy spectrum of 12C isotope by cluster model. The experimental results show that the "Hoyle" state at 7.65 MeV in 12C isotope has a well-developed three-alpha structure. Hence, we select a three-body system and for interaction between the clusters we use modified Yukawa potential plus coulomb potential. Then, we solve the relativistic Klein-Gordon equation using Nikiforov-Uvarov method to calculate the energy spectrum. Finally, the calculated results are compared with the experimental data. The results show that the isotope 12C should be considered as consisting of three-alpha cluster and the modified Yukawa potential is adaptable for cluster interactions.
Variational procedure for nuclear shell-model calculations and energy-variance extrapolation
Shimizu, Noritaka; Mizusaki, Takahiro; Honma, Michio; Tsunoda, Yusuke; Otsuka, Takaharu
2012-01-01
We discuss a variational calculation for nuclear shell-model calculations and propose a new procedure for the energy-variance extrapolation (EVE) method using a sequence of the approximated wave functions obtained by the variational calculation. The wave functions are described as linear combinations of the parity, angular-momentum projected Slater determinants, the energy of which is minimized by the conjugate gradient method obeying the variational principle. The EVE generally works well using the wave functions, but we found some difficult cases where the EVE gives a poor estimation. We discuss the origin of the poor estimation concerning shape coexistence. We found that the appropriate reordering of the Slater determinants allows us to overcome this difficulty and to reduce the uncertainty of the extrapolation.
Calculation of decay half-lives for superheavy elements using the double folding model
Institute of Scientific and Technical Information of China (English)
ZHANG Gao-Long; LE Xiao-Yun
2009-01-01
α decay half-lives of some new synthesized superheavy elements, possibly synthesized superheavy elements and decay products are calculated theoretically within the WKB approximation by using microscopic m-nucleus interaction potentials. These nuclear potentials between the α particle and daughter nuclei are obtained by using the double folding integral of the matter density distribution of the α particle and daughter nuclei with a density-dependent effective nucleon-nucleon interaction, in which the zero-range exchange term is supplemented. The calculated α decay half-lives are compared with those of the different models and experimental data. It is shown that the present calculation successfully provides the half-lives of the observed αdecays for some new superheavy elements and therefore gives reliable predictions for α decay of possibly synthesized superheavy elements in future experiments.
A new method for modeling rough membrane surface and calculation of interfacial interactions.
Zhao, Leihong; Zhang, Meijia; He, Yiming; Chen, Jianrong; Hong, Huachang; Liao, Bao-Qiang; Lin, Hongjun
2016-01-01
Membrane fouling control necessitates the establishment of an effective method to assess interfacial interactions between foulants and rough surface membrane. This study proposed a new method which includes a rigorous mathematical equation for modeling membrane surface morphology, and combination of surface element integration (SEI) method and the composite Simpson's approach for assessment of interfacial interactions. The new method provides a complete solution to quantitatively calculate interfacial interactions between foulants and rough surface membrane. Application of this method in a membrane bioreactor (MBR) showed that, high calculation accuracy could be achieved by setting high segment number, and moreover, the strength of three energy components and energy barrier was remarkably impaired by the existence of roughness on the membrane surface, indicating that membrane surface morphology exerted profound effects on membrane fouling in the MBR. Good agreement between calculation prediction and fouling phenomena was found, suggesting the feasibility of this method.
Fast pencil beam dose calculation for proton therapy using a double-Gaussian beam model
Directory of Open Access Journals (Sweden)
Joakim eda Silva
2015-12-01
Full Text Available The highly conformal dose distributions produced by scanned proton pencil beams are more sensitive to motion and anatomical changes than those produced by conventional radiotherapy. The ability to calculate the dose in real time as it is being delivered would enable, for example, online dose monitoring, and is therefore highly desirable. We have previously described an implementation of a pencil beam algorithm running on graphics processing units (GPUs intended specifically for online dose calculation. Here we present an extension to the dose calculation engine employing a double-Gaussian beam model to better account for the low-dose halo. To the best of our knowledge, it is the first such pencil beam algorithm for proton therapy running on a GPU. We employ two different parametrizations for the halo dose, one describing the distribution of secondary particles from nuclear interactions found in the literature and one relying on directly fitting the model to Monte Carlo simulations of pencil beams in water. Despite the large width of the halo contribution, we show how in either case the second Gaussian can be included whilst prolonging the calculation of the investigated plans by no more than 16%, or the calculation of the most time-consuming energy layers by about 25%. Further, the calculation time is relatively unaffected by the parametrization used, which suggests that these results should hold also for different systems. Finally, since the implementation is based on an algorithm employed by a commercial treatment planning system, it is expected that with adequate tuning, it should be able to reproduce the halo dose from a general beam line with sufficient accuracy.
A general model for stray dose calculation of static and intensity-modulated photon radiation
Energy Technology Data Exchange (ETDEWEB)
Hauri, Pascal, E-mail: pascal.hauri2@uzh.ch; Schneider, Uwe [Faculty of Science, University of Zurich, Zurich 8057, Switzerland and Radiotherapy Hirslanden, Hirslanden Medical Center, Aarau 5000 (Switzerland); Hälg, Roger A.; Besserer, Jürgen [Radiotherapy Hirslanden, Hirslanden Medical Center, Aarau 5000 (Switzerland)
2016-04-15
Purpose: There is an increasing number of cancer survivors who are at risk of developing late effects caused by ionizing radiation such as induction of second tumors. Hence, the determination of out-of-field dose for a particular treatment plan in the patient’s anatomy is of great importance. The purpose of this study was to analytically model the stray dose according to its three major components. Methods: For patient scatter, a mechanistic model was developed. For collimator scatter and head leakage, an empirical approach was used. The models utilize a nominal beam energy of 6 MeV to describe two linear accelerator types of a single vendor. The parameters of the models were adjusted using ionization chamber measurements registering total absorbed dose in simple geometries. Whole-body dose measurements using thermoluminescent dosimeters in an anthropomorphic phantom for static and intensity-modulated treatment plans were compared to the 3D out-of-field dose distributions calculated by a combined model. Results: The absolute mean difference between the whole-body predicted and the measured out-of-field dose of four different plans was 11% with a maximum difference below 44%. Computation time of 36 000 dose points for one field was around 30 s. By combining the model-calculated stray dose with the treatment planning system dose, the whole-body dose distribution can be viewed in the treatment planning system. Conclusions: The results suggest that the model is accurate, fast and can be used for a wide range of treatment modalities to calculate the whole-body dose distribution for clinical analysis. For similar energy spectra, the mechanistic patient scatter model can be used independently of treatment machine or beam orientation.
Study on the Calculation Models of Bus Delay at Bays Using Queueing Theory and Markov Chain
Sun, Li; Sun, Shao-wei; Wang, Dian-hai
2015-01-01
Traffic congestion at bus bays has decreased the service efficiency of public transit seriously in China, so it is crucial to systematically study its theory and methods. However, the existing studies lack theoretical model on computing efficiency. Therefore, the calculation models of bus delay at bays are studied. Firstly, the process that buses are delayed at bays is analyzed, and it was found that the delay can be divided into entering delay and exiting delay. Secondly, the queueing models of bus bays are formed, and the equilibrium distribution functions are proposed by applying the embedded Markov chain to the traditional model of queuing theory in the steady state; then the calculation models of entering delay are derived at bays. Thirdly, the exiting delay is studied by using the queueing theory and the gap acceptance theory. Finally, the proposed models are validated using field-measured data, and then the influencing factors are discussed. With these models the delay is easily assessed knowing the characteristics of the dwell time distribution and traffic volume at the curb lane in different locations and different periods. It can provide basis for the efficiency evaluation of bus bays. PMID:25759720
Study on the Calculation Models of Bus Delay at Bays Using Queueing Theory and Markov Chain
Directory of Open Access Journals (Sweden)
Feng Sun
2015-01-01
Full Text Available Traffic congestion at bus bays has decreased the service efficiency of public transit seriously in China, so it is crucial to systematically study its theory and methods. However, the existing studies lack theoretical model on computing efficiency. Therefore, the calculation models of bus delay at bays are studied. Firstly, the process that buses are delayed at bays is analyzed, and it was found that the delay can be divided into entering delay and exiting delay. Secondly, the queueing models of bus bays are formed, and the equilibrium distribution functions are proposed by applying the embedded Markov chain to the traditional model of queuing theory in the steady state; then the calculation models of entering delay are derived at bays. Thirdly, the exiting delay is studied by using the queueing theory and the gap acceptance theory. Finally, the proposed models are validated using field-measured data, and then the influencing factors are discussed. With these models the delay is easily assessed knowing the characteristics of the dwell time distribution and traffic volume at the curb lane in different locations and different periods. It can provide basis for the efficiency evaluation of bus bays.
Study on the calculation models of bus delay at bays using queueing theory and Markov chain.
Sun, Feng; Sun, Li; Sun, Shao-Wei; Wang, Dian-Hai
2015-01-01
Traffic congestion at bus bays has decreased the service efficiency of public transit seriously in China, so it is crucial to systematically study its theory and methods. However, the existing studies lack theoretical model on computing efficiency. Therefore, the calculation models of bus delay at bays are studied. Firstly, the process that buses are delayed at bays is analyzed, and it was found that the delay can be divided into entering delay and exiting delay. Secondly, the queueing models of bus bays are formed, and the equilibrium distribution functions are proposed by applying the embedded Markov chain to the traditional model of queuing theory in the steady state; then the calculation models of entering delay are derived at bays. Thirdly, the exiting delay is studied by using the queueing theory and the gap acceptance theory. Finally, the proposed models are validated using field-measured data, and then the influencing factors are discussed. With these models the delay is easily assessed knowing the characteristics of the dwell time distribution and traffic volume at the curb lane in different locations and different periods. It can provide basis for the efficiency evaluation of bus bays.
Energy Technology Data Exchange (ETDEWEB)
Kalin, J., E-mail: jan.kalin@zag.s [Slovenian National Building and Civil Engineering Institute, Dimiceva 12, SI-1000 Ljubljana (Slovenia); Petkovsek, B., E-mail: borut.petkovsek@zag.s [Slovenian National Building and Civil Engineering Institute, Dimiceva 12, SI-1000 Ljubljana (Slovenia); Montarnal, Ph., E-mail: philippe.montarnal@cea.f [CEA/Saclay, DM2S/SFME/LSET, Gif-sur-Yvette, 91191 cedex (France); Genty, A., E-mail: alain.genty@cea.f [CEA/Saclay, DM2S/SFME/LSET, Gif-sur-Yvette, 91191 cedex (France); Deville, E., E-mail: estelle.deville@cea.f [CEA/Saclay, DM2S/SFME/LSET, Gif-sur-Yvette, 91191 cedex (France); Krivic, J., E-mail: jure.krivic@geo-zs.s [Geological Survey of Slovenia, Dimiceva 14, SI-1000 Ljubljana (Slovenia); Ratej, J., E-mail: joze.ratej@geo-zs.s [Geological Survey of Slovenia, Dimiceva 14, SI-1000 Ljubljana (Slovenia)
2011-04-15
In the past years the Slovenian Performance Analysis/Safety Assessment team has performed many generic studies for the future Slovenian low and intermediate level waste repository, most recently a Special Safety Analysis for the Krsko site. The modelling approach was to split the problem into three parts: near-field (detailed model of the repository), far-field (i.e., geosphere) and biosphere. In the Special Safety Analysis the code used to perform the near-field calculations was Hydrus2D. Recently the team has begun a cooperation with the French Commisariat al'Energie Atomique/Saclay (CEA/Saclay) and, as a part of this cooperation, began investigations into using the Alliances numerical platform for near-field calculations in order to compare the overall approach and calculated results. The article presents the comparison between these two codes for a silo-type repository that was considered in the Special Safety Analysis. The physical layout and characteristics of the repository are presented and a hydraulic and transport model of the repository is developed and implemented in Alliances. Some analysis of sensitivity to mesh fineness and to simulation timestep has been preformed and is also presented. The compared quantity is the output flux of radionuclides on the boundary of the model. Finally the results from Hydrus2D and Alliances are compared and the differences and similarities are commented.
A theoretical model for calculation of the detective quantum efficiency in granular scintillators
Energy Technology Data Exchange (ETDEWEB)
Cavouras, D. E-mail: cavouras@hol.gr; Kandarakis, I.; Tsoukos, S.; Kateris, A.; Nomicos, C.D.; Panayiotakis, G.S
2001-11-01
A theoretical model has been developed for calculating the detective quantum efficiency (DQE) of scintillators, by taking into account the internal structure of granular scintillators often used in medical imaging detectors. Scintillators were considered to consist of N elementary thin layers containing spherical scintillating grains of equal size. Grains were assumed to be regularly distributed within each thin layer, the thickness of the latter being equal to the grain diameter. Values of the X-ray absorption and X-ray attenuation coefficients, of the intrinsic X-ray to light conversion efficiency and of the optical scattering and absorption coefficients were used as input data to the model. Optical scattering and optical absorption coefficients were determined by fitting the model to experimental luminescence data. The model was employed to calculate the detective quantum efficiency of La{sub 2}O{sub 2}S:Tb, Y{sub 2}O{sub 2}S:Tb, Y{sub 2}O{sub 2}S:Eu, ZnSCdS:Ag, ZnSCdS:Au,Cu scintillators. Results of the calculations were found close to values published in previous studies.
MATHEMATICAL MODEL FOR CALCULATION OF INFORMATION RISKS FOR INFORMATION AND LOGISTICS SYSTEM
Directory of Open Access Journals (Sweden)
A. G. Korobeynikov
2015-05-01
Full Text Available Subject of research. The paper deals with mathematical model for assessment calculation of information risks arising during transporting and distribution of material resources in the conditions of uncertainty. Meanwhile information risks imply the danger of origin of losses or damage as a result of application of information technologies by the company. Method. The solution is based on ideology of the transport task solution in stochastic statement with mobilization of mathematical modeling theory methods, the theory of graphs, probability theory, Markov chains. Creation of mathematical model is performed through the several stages. At the initial stage, capacity on different sites depending on time is calculated, on the basis of information received from information and logistic system, the weight matrix is formed and the digraph is under construction. Then there is a search of the minimum route which covers all specified vertexes by means of Dejkstra algorithm. At the second stage, systems of differential Kolmogorov equations are formed using information about the calculated route. The received decisions show probabilities of resources location in concrete vertex depending on time. At the third stage, general probability of the whole route passing depending on time is calculated on the basis of multiplication theorem of probabilities. Information risk, as time function, is defined by multiplication of the greatest possible damage by the general probability of the whole route passing. In this case information risk is measured in units of damage which corresponds to that monetary unit which the information and logistic system operates with. Main results. Operability of the presented mathematical model is shown on a concrete example of transportation of material resources where places of shipment and delivery, routes and their capacity, the greatest possible damage and admissible risk are specified. The calculations presented on a diagram showed
Calculation of accurate small angle X-ray scattering curves from coarse-grained protein models
Directory of Open Access Journals (Sweden)
Stovgaard Kasper
2010-08-01
Full Text Available Abstract Background Genome sequencing projects have expanded the gap between the amount of known protein sequences and structures. The limitations of current high resolution structure determination methods make it unlikely that this gap will disappear in the near future. Small angle X-ray scattering (SAXS is an established low resolution method for routinely determining the structure of proteins in solution. The purpose of this study is to develop a method for the efficient calculation of accurate SAXS curves from coarse-grained protein models. Such a method can for example be used to construct a likelihood function, which is paramount for structure determination based on statistical inference. Results We present a method for the efficient calculation of accurate SAXS curves based on the Debye formula and a set of scattering form factors for dummy atom representations of amino acids. Such a method avoids the computationally costly iteration over all atoms. We estimated the form factors using generated data from a set of high quality protein structures. No ad hoc scaling or correction factors are applied in the calculation of the curves. Two coarse-grained representations of protein structure were investigated; two scattering bodies per amino acid led to significantly better results than a single scattering body. Conclusion We show that the obtained point estimates allow the calculation of accurate SAXS curves from coarse-grained protein models. The resulting curves are on par with the current state-of-the-art program CRYSOL, which requires full atomic detail. Our method was also comparable to CRYSOL in recognizing native structures among native-like decoys. As a proof-of-concept, we combined the coarse-grained Debye calculation with a previously described probabilistic model of protein structure, TorusDBN. This resulted in a significant improvement in the decoy recognition performance. In conclusion, the presented method shows great promise for
Santillana, Mauricio; Le Sager, Philippe; Jacob, Daniel J.; Brenner, Michael P.
2010-11-01
We present a computationally efficient adaptive method for calculating the time evolution of the concentrations of chemical species in global 3-D models of atmospheric chemistry. Our strategy consists of partitioning the computational domain into fast and slow regions for each chemical species at every time step. In each grid box, we group the fast species and solve for their concentration in a coupled fashion. Concentrations of the slow species are calculated using a simple semi-implicit formula. Separation of species between fast and slow is done on the fly based on their local production and loss rates. This allows for example to exclude short-lived volatile organic compounds (VOCs) and their oxidation products from chemical calculations in the remote troposphere where their concentrations are negligible, letting the simulation determine the exclusion domain and allowing species to drop out individually from the coupled chemical calculation as their production/loss rates decline. We applied our method to a 1-year simulation of global tropospheric ozone-NO x-VOC-aerosol chemistry using the GEOS-Chem model. Results show a 50% improvement in computational performance for the chemical solver, with no significant added error.
System of Modelling and Calculation Analysis of Neutron- Physical Experiments at Fast Reactors
Energy Technology Data Exchange (ETDEWEB)
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)
Model calculation of N2 Vegard-Kaplan band emissions in Martian dayglow
Jain, Sonal Kumar
2011-01-01
A model for N2 Vegard-Kaplan (VK) band (A^3Sigma_u^+ - X^1Sigma_g^+) emissions in Martian dayglow has been developed to explain the recent observations made by the Spectroscopy for Investigation of Characteristics of the Atmosphere of Mars (SPICAM) ultraviolet spectrograph aboard Mars Express. Steady state photoelectron fluxes and volume excitation rates have been calculated using the analytical yield spectra technique. Since interstate cascading is important for triplet states of N2, the population of any given level of N2 triplet states is calculated under statistical equilibrium considering direct excitation, cascading, and quenching effects. Relative population of all vibrational levels of each triplet state is calculated in the model. Line of sight intensities and height-integrated overhead intensities have been calculated for VK, first positive (B^3Pi_g - A^3Sigma_u^+), second positive (C^3Pi_u - B^3Pi_g), and Wu-Benesch (W^3Delta_u - B^3Pi_g) bands of N2. A reduction in the N2 density by a factor of 3 ...
MPS solidification model. Analysis and calculation of macrosegregation in a casting ingot
Poirier, D. R.; Maples, A. L.
1985-01-01
Work performed on several existing solidification models for which computer codes and documentation were developed is presented. The models describe the solidification of alloys in which there is a time varying zone of coexisting solid and liquid phases; i.e., the S/L zone. The primary purpose of the models is to calculate macrosegregation in a casting or ingot which results from flow of interdendritic liquid in this S/L zone during solidification. The flow, driven by solidification contractions and by gravity acting on density gradients in the interdendritic liquid, is modeled as flow through a porous medium. In Model 1, the steady state model, the heat flow characteristics are those of steady state solidification; i.e., the S/L zone is of constant width and it moves at a constant velocity relative to the mold. In Model 2, the unsteady state model, the width and rate of movement of the S/L zone are allowed to vary with time as it moves through the ingot. Each of these models exists in two versions. Models 1 and 2 are applicable to binary alloys; models 1M and 2M are applicable to multicomponent alloys.
Necessity of using heterogeneous ellipsoidal Earth model with terrain to calculate co-seismic effect
Cheng, Huihong; Zhang, Bei; Zhang, Huai; Huang, Luyuan; Qu, Wulin; Shi, Yaolin
2016-04-01
Co-seismic deformation and stress changes, which reflect the elasticity of the earth, are very important in the earthquake dynamics, and also to other issues, such as the evaluation of the seismic risk, fracture process and triggering of earthquake. Lots of scholars have researched the dislocation theory and co-seismic deformation and obtained the half-space homogeneous model, half-space stratified model, spherical stratified model, and so on. Especially, models of Okada (1992) and Wang (2003, 2006) are widely applied in the research of calculating co-seismic and post-seismic effects. However, since both semi-infinite space model and layered model do not take the role of the earth curvature or heterogeneity or topography into consideration, there are large errors in calculating the co-seismic displacement of a great earthquake in its impacted area. Meanwhile, the computational methods of calculating the co-seismic strain and stress are different between spherical model and plane model. Here, we adopted the finite element method which could well deal with the complex characteristics (such as anisotropy, discontinuities) of rock and different conditions. We use the mash adaptive technique to automatically encrypt the mesh at the fault and adopt the equivalent volume force replace the dislocation source, which can avoid the difficulty in handling discontinuity surface with conventional (Zhang et al., 2015). We constructed an earth model that included earth's layered structure and curvature, the upper boundary was set as a free surface and the core-mantle boundary was set under buoyancy forces. Firstly, based on the precision requirement, we take a testing model - - a strike-slip fault (the length of fault is 500km and the width is 50km, and the slippage is 10m) for example. Because of the curvature of the Earth, some errors certainly occur in plane coordinates just as previous studies (Dong et al., 2014; Sun et al., 2012). However, we also found that: 1) the co
Verification of mathematical models for calculation of viscosity of molten oxide systems
Directory of Open Access Journals (Sweden)
S. Rosypalová
2014-06-01
Full Text Available The subject of this work is the comparison of numerically obtained values of dynamic viscosity using different types of mathematical models and experimentally measured data of viscosity of oxide systems. The ternary system of SiO2-CaO-Al2O3, which presents simplified base of the casting powders used in technological process, was submitted to the experiment. Experimental research of dynamic viscosity is highly limited by its complexity. That’s why model studies play such an important role in this field. For mathematic calculation of viscosity the NPL model, Iida model and Urbain model were chosen. The results of simulation were compared with the experimentally obtained values of viscosity.
Calculation of Forming Limits for Sheet Metal using an Enhanced Continuous Damage Fracture Model
Nguyen, Ngoc-Trung; Kim, Dae-Young; Kim, Heon Young
2011-08-01
An enhanced continuous damage fracture model was introduced in this paper to calculate forming limits of sheet metal. The fracture model is a combination of a fracture criterion and a continuum damage constitutive law. A modified McClintock void growth fracture criterion was incorporated with a coupled damage-plasticity Gurson-type constitutive law. Also, by introducing a Lode angle dependent parameter to define the loading asymmetry condition, the shear effect was phenomenologically taken into account. The proposed fracture model was implemented using user-subroutines in commercial finite element software. The model was calibrated and correlated by the uniaxial tension, shear and notched specimens tests. Application of the fracture model for the LDH tests was discussed and the simulation results were compared with the experimental data.
Implications of imprecision in kinetic rate data for photochemical model calculations
Energy Technology Data Exchange (ETDEWEB)
Stewart, R.W.; Thompson, A.M. [National Aeronautics and Space Administration, Greenbelt, MD (United States). Goddard Space Flight Center
1997-12-31
Evaluation of uncertainties in photochemical model calculations is of great importance to scientists performing assessment modeling. A major source of uncertainty is the measurement imprecision inherent in photochemical reaction rate data that modelers rely on. A rigorous method of evaluating the impact of data imprecision on computational uncertainty is the study of error propagation using Monte Carlo techniques. There are two problems with the current implementation of the Monte Carlo method. First, there is no satisfactory way of accounting for the variation of imprecision with temperature in 1, 2, or 3D models; second, due to its computational expense, it is impractical in 3D model studies. These difficulties are discussed. (author) 4 refs.
Dang, Phuong-Thanh; Herman, Michael F
2009-02-01
A semiclassical surface hopping model is presented for the calculation of nonadiabatic transition probabilities for the case in which the avoided crossing point is in the classically forbidden regions. The exact potentials and coupling are replaced with simple functional forms that are fitted to the values, evaluated at the turning point in the classical motion, of the Born-Oppenheimer potentials, the nonadiabatic coupling, and their first few derivatives. For the one-dimensional model considered, reasonably accurate results for transition probabilities are obtained down to around 10(-10). The possible extension of this model to many dimensional problems is discussed. The fact that the model requires only information at the turning point, a point that the trajectories encounter would be a significant advantage in many dimensional problems over Landau-Zener type models, which require information at the avoided crossing seam, which is in the forbidden region where the trajectories do not go.
Comparison of calculation methods for the tunnel splitting at excited states of biaxial spin models
Institute of Scientific and Technical Information of China (English)
Cui Xiao-Bo; Chen Zhi-De
2004-01-01
We present the calculation and comparison of tunnel splitting at excited levels of biaxial spin models by various methods, including the generalized instanton method, the generalized path integral method for coherent spin states,the perturbation method, and the exact method by numerical diagonalization of the Hamiltonian. It is found that,for integer spin with spin number around 10, tunnel splitting predicted by the generalized path integral for coherent spin states is about 10-n times of the exact numerical result for the nth excited level, while the ratio of the results of the perturbation method and the exact numerical method diverges in the large spin limit. We thus conclude that the generalized instanton method is the best approximate way for calculating tunnel splitting in spin models.
Large-scale shell-model calculations of nuclei around mass 210
Teruya, E.; Higashiyama, K.; Yoshinaga, N.
2016-06-01
Large-scale shell-model calculations are performed for even-even, odd-mass, and doubly odd nuclei of Pb, Bi, Po, At, Rn, and Fr isotopes in the neutron deficit region (Z ≥82 ,N ≤126 ) assuming 208Pb as a doubly magic core. All the six single-particle orbitals between the magic numbers 82 and 126, namely, 0 h9 /2,1 f7 /2,0 i13 /2,2 p3 /2,1 f5 /2 , and 2 p1 /2 , are considered. For a phenomenological effective two-body interaction, one set of the monopole pairing and quadrupole-quadrupole interactions including the multipole-pairing interactions is adopted for all the nuclei considered. The calculated energies and electromagnetic properties are compared with the experimental data. Furthermore, many isomeric states are analyzed in terms of the shell-model configurations.
Raman spectroscopy, ab-initio model calculations, and conformational, equilibria in ionic liquids
DEFF Research Database (Denmark)
Berg, Rolf W.
2009-01-01
spectroscopy and ab-initio molecular orbital calculations. A discussion is given, based mainly on some recent FT- Raman spectroscopic results on the model ionic liquid system of 1-butyl-3-methyl-imidazolium ([C4C1Im]+X-) salts. The rotational isomerism of the [C4C1Im]+ cation is described: the presence of anti...... systems in the future. A few examples will be discussed. Contents 12.1 Introduction...........307 12.2 Brief introduction to Raman spectroscopy ..............309 12.2.1 Basics .....................309 12.2.2 Experimental, fluorescence and fouriertransform- Raman spectroscopy instrumentation ...... 311 12.......3 Brief introduction to ab-initio model calculations .... 312 12.4 Case study on Raman spectroscopy and structure of imidazolium-based ionic liquids ..... 312 12.5 Raman spectra and structure of [C4C1Im]+ liquids ..... 315 12.6 Normal mode analysis and rotational isomerism of the [C4C1Im]+ cation...
A theoretical model for calculation of molecular stopping power. Ph.D. Thesis
Xu, Y. J.
1984-01-01
A modified local plasma model is established. The Gordon-Kim's molecular charged density model is employed to obtain a formula to evaluate the stopping power of many useful molecular systems. The stopping power of H2 and He gas was calculated for incident proton energy ranging from 100 keV to 2.5 MeV. The stopping power of O2, N2, and water vapor was also calculated for incident proton energy ranging from 40 keV. to 2.5 MeV. Good agreement with experimental data was obtained. A discussion of molecular effects leading to department from Bragg's rule is presented. The equipartition rule and the effect of nuclear momentum recoiling in stopping power are also discussed.
Energy Technology Data Exchange (ETDEWEB)
Baxter, R J [Mathematical Sciences Institute, Australian National University, Canberra, ACT 0200 (Australia)
2010-04-09
For the Ising model, the calculation of the spontaneous magnetization leads to the problem of evaluating a determinant. Yang did this by calculating the eigenvalues in the large-lattice limit. Montroll, Potts and Ward expressed it as a Toeplitz determinant and used Szego's theorem: this is almost certainly the route originally travelled by Onsager. For the corresponding problem in the superintegrable chiral Potts model, neither approach appears to work: here we show that the determinant D{sub PQ} can be expressed as that of a product of two Cauchy-like matrices. One can then use the elementary exact formula for the Cauchy determinant. One of course regains the known result, originally conjectured in 1989.
DEFF Research Database (Denmark)
Blurton, Steven Paul; Kesselmeier, M.; Gondan, Matthias
2012-01-01
related work on the density of first-passage times [Navarro, D.J., Fuss, I.G. (2009). Fast and accurate calculations for first-passage times in Wiener diffusion models. Journal of Mathematical Psychology, 53, 222-230]. Two representations exist for the distribution, both including infinite series. We......We propose an improved method for calculating the cumulative first-passage time distribution in Wiener diffusion models with two absorbing barriers. This distribution function is frequently used to describe responses and error probabilities in choice reaction time tasks. The present work extends...... derive upper bounds for the approximation error resulting from finite truncation of the series, and we determine the number of iterations required to limit the error below a pre-specified tolerance. For a given set of parameters, the representation can then be chosen which requires the least...
Völlinger, Christine; Russenschuck, Stephan
2001-01-01
Field variations in the LHC superconducting magnets, e. g. during the ramping of the magnets, induce magnetization currents in the superconducting material, the so-called persistent currents that do not decay but persist due to the lack of resistivity. This paper describes a semi-analytical hysteresis model for hard superconductors, which has been developed for the computation of the total field errors arising from persistent currents. Since the superconducting coil is surrounded by a ferromagnetic yoke structure, the persistent current model is combined with the finite element method (FEM), as the non-linear yoke can only be calculated numerically. The used finite element method is based on a reduced vector potential formulation that avoids the meshing of the coil while calculating the part of the field arising from the source currents by means of the Biot-Savart Law. The combination allows to determine persistent current induced field errors as function of the excitation and for arbitrarily shaped iron yoke...
Ground moving target signal model and power calculation in forward scattering micro radar
Institute of Scientific and Technical Information of China (English)
LONG Teng; HU Cheng; MIKHAIL Cherniakov
2009-01-01
Forward scattering micro radar is used for situation awareness;its operational range is relatively short because of the battery power and local horizon,the free space propagation model is not appropriate.The ground moving targets,such as humans,cars and tanks,have only comparable size with the transmitted signal wavelength;the point target model and the linear change of observation angle are not applicable.In this paper,the signal model of ground moving target is developed based on the case of forward scattering micro radar,considering the two-ray propagation model and area target model,and nonlinear change of observation angle as well as high order phase error.Furthermore,the analytical form of the received power from moving target has been obtained.Using the simulated forward scattering radar cross section,the received power of theoretical calculation is near to that of measured data.In addition,the simulated signal model of ground moving target is perfectly matched with the experimented data.All these results show the correctness of analytical calculation completely.
Atmospheric Modelling for Neptune's Methane D/H Ratio - Preliminary Results
Cotton, Daniel V; Bott, Kimberly; Bailey, Jeremy
2015-01-01
The ratio of deuterium to hydrogen (D/H ratio) of Solar System bodies is an important clue to their formation histories. Here we fit a Neptunian atmospheric model to Gemini Near Infrared Spectrograph (GNIRS) high spectral resolution observations and determine the D/H ratio in methane absorption in the infrared H-band ($\\sim$ 1.6 {\\mu}m). The model was derived using our radiative transfer software VSTAR (Versatile Software for the Transfer of Atmospheric Radiation) and atmospheric fitting software ATMOF (ATMOspheric Fitting). The methane line list used for this work has only become available in the last few years, enabling a refinement of earlier estimates. We identify a bright region on the planetary disc and find it to correspond to an optically thick lower cloud. Our preliminary determination of CH$_{\\rm 3}$D/CH$_{\\rm 4}$ is 3.0$\\times10^{-4}$, which is in line with the recent determination of Irwin et al. (2014) of 3.0$^{+1.0}_{-0.9}\\sim\\times10^{-4}$, made using the same model parameters and line list but...
Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling
Institute of Scientific and Technical Information of China (English)
LAI; Geying; YU; Ge; GUI; Feng
2006-01-01
With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53% and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 30% and 16%, and sewerage in both forms of point source and non-point source are TN 31% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.
Directory of Open Access Journals (Sweden)
Jun Araki
Full Text Available Colostomy is conventionally the only treatment for anal dysfunction. Recently, a few trials of anorectal transplantation in animals have been published; however, further development of this technique is required. Moreover, it is crucial to perform this research in dogs, which resemble humans in anorectal anatomy and biology. We designed a canine anorectal transplantation model, wherein anorectal autotransplantation was performed by anastomoses of the rectum, inferior mesenteric artery (IMA and vein, and pudendal nerves. Resting pressure in the anal canal and anal canal pressure fluctuation were measured before and after surgery. Graft pathology was examined three days after surgery. The anal blood supply was compared with that in three beagles using indocyanine green (ICG fluorescence angiography. The anorectal graft had sufficient arterial blood supply from the IMA; however, the graft's distal end was congested and necrotized. Functional examination demonstrated reduced resting pressure and the appearance of an irregular anal canal pressure wave after surgery. ICG angiography showed that the pudendal arteries provided more blood flow than the IMA to the anal segment. This is the first canine model of preliminary anorectal autotransplantation, and it demonstrates the possibility of establishing a transplantation model in dogs using appropriate vascular anastomoses, thus contributing to the progress of anorectal transplantation.
Influence of polarization and a source model for dose calculation in MRT
Energy Technology Data Exchange (ETDEWEB)
Bartzsch, Stefan, E-mail: s.bartzsch@dkfz.de; Oelfke, Uwe [The Institute of Cancer Research, 15 Cotswold Road, Belmont, Sutton, Surrey SM2 5NG, United Kingdom and Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D-69120 Heidelberg (Germany); Lerch, Michael; Petasecca, Marco [Centre for Medical Radiation Physics, University of Wollongong, Northfields Avenue, Wollongong 2522 (Australia); Bräuer-Krisch, Elke [European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, 38000 Grenoble (France)
2014-04-15
Purpose: Microbeam Radiation Therapy (MRT), an alternative preclinical treatment strategy using spatially modulated synchrotron radiation on a micrometer scale, has the great potential to cure malignant tumors (e.g., brain tumors) while having low side effects on normal tissue. Dose measurement and calculation in MRT is challenging because of the spatial accuracy required and the arising high dose differences. Dose calculation with Monte Carlo simulations is time consuming and their accuracy is still a matter of debate. In particular, the influence of photon polarization has been discussed in the literature. Moreover, it is controversial whether a complete knowledge of phase space trajectories, i.e., the simulation of the machine from the wiggler to the collimator, is necessary in order to accurately calculate the dose. Methods: With Monte Carlo simulations in the Geant4 toolkit, the authors investigate the influence of polarization on the dose distribution and the therapeutically important peak to valley dose ratios (PVDRs). Furthermore, the authors analyze in detail phase space information provided byMartínez-Rovira et al. [“Development and commissioning of a Monte Carlo photon model for the forthcoming clinical trials in microbeam radiation therapy,” Med. Phys. 39(1), 119–131 (2012)] and examine its influence on peak and valley doses. A simple source model is developed using parallel beams and its applicability is shown in a semiadjoint Monte Carlo simulation. Results are compared to measurements and previously published data. Results: Polarization has a significant influence on the scattered dose outside the microbeam field. In the radiation field, however, dose and PVDRs deduced from calculations without polarization and with polarization differ by less than 3%. The authors show that the key consequences from the phase space information for dose calculations are inhomogeneous primary photon flux, partial absorption due to inclined beam incidence outside
Lattice dynamics and spin-phonon interactions in multiferroic RMn2O5: Shell model calculations
Litvinchuk, A. P.
2009-08-01
The results of the shell model lattice dynamics calculations of multiferroic RMn2O5 materials (space group Pbam) are reported. Theoretical even-parity eigenmode frequencies are compared with those obtained experimentally in polarized Raman scattering experiments for R=Ho,Dy. Analysis of displacement patterns allows to identify vibrational modes which facilitate spin-phonon coupling by modulating the Mn-Mn exchange interaction and provides explanation of the observed anomalous temperature behavior of phonons.
A quark model calculation of yy->pipi including final-state interactions
Blundell, H G; Hay, G; Swanso, E
2000-01-01
A quark model calculation of the processes yy->pi+pi- and yy->pipi is performed. At tree level, only charged pions couple to the initial state photons and neutral pions are not exceeded in the final state. However a small but significant cross section is observed. We demonstrate that this may be accounted for by a rotation in isospin space induced by final-state interactions.
Raman Spectroscopy and Ab-Initio Model Calculations on Ionic Liquids
DEFF Research Database (Denmark)
Berg, Rolf W.
2007-01-01
spectroscopy and ab-initio molecular orbital calculations. A discussion is given, based mainly on some recent FT-Raman spectroscopic results on the model ionic liquid system of 1-butyl-3-methylimidazolium ([C4mim][X]) salts. The rotational isomerism of the [C4mim]þ cation is described: the presence of anti...... will be applied to many more systems in the future. A few examples will be discussed....
Model calculations of the relative effects of CFCs and their replacements on stratospheric ozone
Fisher, Donald A.; Hales, Charles H.; Filkin, David L.; Ko, Malcolm K. W.; Sze, N. Dak
1990-01-01
Because chlorine has been linked to the destruction of stratospheric ozone, the use of many fully halogenated compounds, such as the chlorofluorocarbons CFC-11 and -12, is restricted by international agreement. Hydrohalocarbons are under intensive development as replacements for CFCs. Because they contain hydrogen, these gases are susceptible to tropospheric destruction which significantly shortens their atmospheric lifetimes,. Model calculations show that chlorine-containing hydrohalocarbons have less effect on ozone, by an order of magnitude, than their regulated counterparts.
Nuclear structure calculations in $^{20}$Ne with No-Core Configuration-Interaction model
Konieczka, Maciej
2016-01-01
Negative parity states in $^{20}$Ne and Gamow-Teller strength distribution for the ground-state beta-decay of $^{20}$Na are calculated for the very first time using recently developed No-Core Configuration-Interaction model. The approach is based on multi-reference density functional theory involving isospin and angular-momentum projections. Advantages and shortcomings of the method are briefly discussed.
A deterministic partial differential equation model for dose calculation in electron radiotherapy
Energy Technology Data Exchange (ETDEWEB)
Duclous, R; Dubroca, B [CELIA and IMB Laboratories, Bordeaux University, 33405 Talence (France); Frank, M, E-mail: duclous@celia.u-bordeaux1.f, E-mail: dubroca@celia.u-bordeaux1.f, E-mail: frank@mathcces.rwth-aachen.d [Department of Mathematics and Center for Computational Engineering Science, RWTH Aachen University, Schinkelstr. 2, 52062 Aachen (Germany)
2010-07-07
High-energy ionizing radiation is a prominent modality for the treatment of many cancers. The approaches to electron dose calculation can be categorized into semi-empirical models (e.g. Fermi-Eyges, convolution-superposition) and probabilistic methods (e.g. Monte Carlo). A third approach to dose calculation has only recently attracted attention in the medical physics community. This approach is based on the deterministic kinetic equations of radiative transfer. We derive a macroscopic partial differential equation model for electron transport in tissue. This model involves an angular closure in the phase space. It is exact for the free streaming and the isotropic regime. We solve it numerically by a newly developed HLLC scheme based on Berthon et al (2007 J. Sci. Comput. 31 347-89) that exactly preserves the key properties of the analytical solution on the discrete level. We discuss several test cases taken from the medical physics literature. A test case with an academic Henyey-Greenstein scattering kernel is considered. We compare our model to a benchmark discrete ordinate solution. A simplified model of electron interactions with tissue is employed to compute the dose of an electron beam in a water phantom, and a case of irradiation of the vertebral column. Here our model is compared to the PENELOPE Monte Carlo code. In the academic example, the fluences computed with the new model and a benchmark result differ by less than 1%. The depths at half maximum differ by less than 0.6%. In the two comparisons with Monte Carlo, our model gives qualitatively reasonable dose distributions. Due to the crude interaction model, these so far do not have the accuracy needed in clinical practice. However, the new model has a computational cost that is less than one-tenth of the cost of a Monte Carlo simulation. In addition, simulations can be set up in a similar way as a Monte Carlo simulation. If more detailed effects such as coupled electron-photon transport, bremsstrahlung
A deterministic partial differential equation model for dose calculation in electron radiotherapy
Duclous, R.; Dubroca, B.; Frank, M.
2010-07-01
High-energy ionizing radiation is a prominent modality for the treatment of many cancers. The approaches to electron dose calculation can be categorized into semi-empirical models (e.g. Fermi-Eyges, convolution-superposition) and probabilistic methods (e.g. Monte Carlo). A third approach to dose calculation has only recently attracted attention in the medical physics community. This approach is based on the deterministic kinetic equations of radiative transfer. We derive a macroscopic partial differential equation model for electron transport in tissue. This model involves an angular closure in the phase space. It is exact for the free streaming and the isotropic regime. We solve it numerically by a newly developed HLLC scheme based on Berthon et al (2007 J. Sci. Comput. 31 347-89) that exactly preserves the key properties of the analytical solution on the discrete level. We discuss several test cases taken from the medical physics literature. A test case with an academic Henyey-Greenstein scattering kernel is considered. We compare our model to a benchmark discrete ordinate solution. A simplified model of electron interactions with tissue is employed to compute the dose of an electron beam in a water phantom, and a case of irradiation of the vertebral column. Here our model is compared to the PENELOPE Monte Carlo code. In the academic example, the fluences computed with the new model and a benchmark result differ by less than 1%. The depths at half maximum differ by less than 0.6%. In the two comparisons with Monte Carlo, our model gives qualitatively reasonable dose distributions. Due to the crude interaction model, these so far do not have the accuracy needed in clinical practice. However, the new model has a computational cost that is less than one-tenth of the cost of a Monte Carlo simulation. In addition, simulations can be set up in a similar way as a Monte Carlo simulation. If more detailed effects such as coupled electron-photon transport, bremsstrahlung
Directory of Open Access Journals (Sweden)
Xuan L Liu
Full Text Available The phase relations and thermodynamic properties of the condensed Al-Co-Cr ternary alloy system are investigated using first-principles calculations based on density functional theory (DFT and phase-equilibria experiments that led to X-ray diffraction (XRD and electron probe micro-analysis (EPMA measurements. A thermodynamic description is developed by means of the calculations of phase diagrams (CALPHAD method using experimental and computational data from the present work and the literature. Emphasis is placed on modeling the bcc-A2, B2, fcc-γ, and tetragonal-σ phases in the temperature range of 1173 to 1623 K. Liquid, bcc-A2 and fcc-γ phases are modeled using substitutional solution descriptions. First-principles special quasirandom structures (SQS calculations predict a large bcc-A2 (disordered/B2 (ordered miscibility gap, in agreement with experiments. A partitioning model is then used for the A2/B2 phase to effectively describe the order-disorder transitions. The critically assessed thermodynamic description describes all phase equilibria data well. A2/B2 transitions are also shown to agree well with previous experimental findings.
Thermodynamic modeling of the Fe–Mo system coupled with experiments and ab initio calculations
Energy Technology Data Exchange (ETDEWEB)
Rajkumar, V.B.; Hari Kumar, K.C., E-mail: kchkumar@iitm.ac.in
2014-10-25
Highlights: • Gibbs energy functions for all stable phases in the Fe–Mo system obtained using Calphad method. • Ab initio calculation results are employed to improve Gibbs energy functions. • New experimental data have been incorporated in the optimization. • Thermochemical properties: energy of formation, cohesive energy. • Calculated values are compared with experimental results. - Abstract: In this paper we report the Gibbs energy functions for all stable phases in the Fe–Mo system obtained using Calphad method. Newly measured enthalpy increment data, tie-line data and liquidus data for selected compositions are used as input for the Gibbs energy modeling, along with carefully selected thermochemical and phase diagram data from literature. Further, ab initio generated energy of formation at 0 K for the intermetallic phases and end-members of the sublattice model for the μ phase and the σ phase are also used in the optimization of model parameters of the Gibbs energy functions. Calculated phase diagram and the thermochemical properties show good agreement with the experimental data.
A NOVEL SLIGHTLY COMPRESSIBLE MODEL FOR LOW MACH NUMBER PERFECT GAS FLOW CALCULATION
Institute of Scientific and Technical Information of China (English)
邓小刚; 庄逢甘
2002-01-01
By analyzing the characteristics of low Mach number perfect gas flows, a novel Slightly Compressible Model (SCM) for low Mach number perfect gas flows is derived. In view of numerical calculations, this model is proved very efficient,for it is kept within the p-v frame but does not have to satisfy the time consuming divergence-free condition in order to get the incompressible Navier-Stokes equation solutions. Writing the equations in the form of conservation laws, we have derived the characteristic systems which are necessary for numerical calculations. A cellcentered finite-volume method with flux difference upwind-biased schemes is used for the equation solutions and a new Exact Newton Relaxation (ENR) implicit method is developed. Various computed results are presented to validate the present model.Laminar flow solutions over a circular cylinder with wake developing and vortex shedding are presented. Results for inviscid flow over a sphere are compared in excellent agreement with the exact analytic incompressible solution. Three-dimensional viscous flow solutions over sphere and prolate spheroid are also calculated and compared well with experiments and other incompressible solutions. Finally, good convergent performaces are shown for sphere viscous flows.
Joint kinematic calculation based on clinical direct kinematic versus inverse kinematic gait models.
Kainz, H; Modenese, L; Lloyd, D G; Maine, S; Walsh, H P J; Carty, C P
2016-06-14
Most clinical gait laboratories use the conventional gait analysis model. This model uses a computational method called Direct Kinematics (DK) to calculate joint kinematics. In contrast, musculoskeletal modelling approaches use Inverse Kinematics (IK) to obtain joint angles. IK allows additional analysis (e.g. muscle-tendon length estimates), which may provide valuable information for clinical decision-making in people with movement disorders. The twofold aims of the current study were: (1) to compare joint kinematics obtained by a clinical DK model (Vicon Plug-in-Gait) with those produced by a widely used IK model (available with the OpenSim distribution), and (2) to evaluate the difference in joint kinematics that can be solely attributed to the different computational methods (DK versus IK), anatomical models and marker sets by using MRI based models. Eight children with cerebral palsy were recruited and presented for gait and MRI data collection sessions. Differences in joint kinematics up to 13° were found between the Plug-in-Gait and the gait 2392 OpenSim model. The majority of these differences (94.4%) were attributed to differences in the anatomical models, which included different anatomical segment frames and joint constraints. Different computational methods (DK versus IK) were responsible for only 2.7% of the differences. We recommend using the same anatomical model for kinematic and musculoskeletal analysis to ensure consistency between the obtained joint angles and musculoskeletal estimates.
The calculation of the circulation in South China Sea by a diagnostic model
Institute of Scientific and Technical Information of China (English)
ZHOU Weidong; YANG Yang; DONG Danpeng
2008-01-01
A high resolved two - dimensional linear global diagnostic model combining with the dynamical calculation is used to calculate ve- locity field in the South China Sea(SCS). The study of model results shows that eddy diffusion does not change basic structure of circulation in the SCS and does not change the direction of invasive water, but changes the value of transport considerably espe- cially in straits. The velocity field is not changed whether the wind stress is considered or not. This result shows the circulation is largely determined by a density field which well records most of the important contribution of the wind stress effect. Potential vor- ticity is calculated to testify the dynamics of the model results. The result shows that a good conservation of the nonlinear PV. This indicates most effects of the important nonlinear processes are well recorded in density and the nonlinear term is negligible so that the simplified model is reliable. The model results show the water exchanges between the SCS and open ocean or surrounding seas. Cold deep water invades through Luzon Strait and Warm shallow water is pushed out mainly through Karimata Straits. The model results also reveal the structure of the circulation in the SCS basin. In two circulations of upper and middle layers, a cyclon- ic one in the north and an anti-cyclonic one in the south, reflect the climatologic average of the circulation driven by monsoon. In the deep or bottom layer, these two circulations reflect the topography of the basin. Above the middle layer, invasive water enters westward in the north but the way of invasion of Kuroshio is not clear. Below the deep layer, a current goes down south near the east basin , and invasive water enters in the basin from the west Pacific.
Energy Technology Data Exchange (ETDEWEB)
Dolly, S [Washington University School of Medicine, Saint Louis, MO (United States); University of Missouri, Columbia, MO (United States); Chen, H; Anastasio, M; Mutic, S; Li, H [Washington University School of Medicine, Saint Louis, MO (United States)
2015-06-15
Purpose: Local noise power spectrum (NPS) properties are significantly affected by calculation variables and CT acquisition and reconstruction parameters, but a thoughtful analysis of these effects is absent. In this study, we performed a complete analysis of the effects of calculation and imaging parameters on the NPS. Methods: The uniformity module of a Catphan phantom was scanned with a Philips Brilliance 64-slice CT simulator using various scanning protocols. Images were reconstructed using both FBP and iDose4 reconstruction algorithms. From these images, local NPS were calculated for regions of interest (ROI) of varying locations and sizes, using four image background removal methods. Additionally, using a predetermined ground truth, NPS calculation accuracy for various calculation parameters was compared for computer simulated ROIs. A complete analysis of the effects of calculation, acquisition, and reconstruction parameters on the NPS was conducted. Results: The local NPS varied with ROI size and image background removal method, particularly at low spatial frequencies. The image subtraction method was the most accurate according to the computer simulation study, and was also the most effective at removing low frequency background components in the acquired data. However, first-order polynomial fitting using residual sum of squares and principle component analysis provided comparable accuracy under certain situations. Similar general trends were observed when comparing the NPS for FBP to that of iDose4 while varying other calculation and scanning parameters. However, while iDose4 reduces the noise magnitude compared to FBP, this reduction is spatial-frequency dependent, further affecting NPS variations at low spatial frequencies. Conclusion: The local NPS varies significantly depending on calculation parameters, image acquisition parameters, and reconstruction techniques. Appropriate local NPS calculation should be performed to capture spatial variations of
Model for the calculation of pressure loss through heavy fuel oil transfer pipelines
Directory of Open Access Journals (Sweden)
Hector Luis Laurencio-Alfonso,
2012-10-01
Full Text Available Considering the limitations of methodologies and empirical correlations in the evaluation of simultaneous effects produced by viscous and mix strength during the transfer of fluids through pipelines, this article presents the functional relationships that describe the pressure variations for the non-Newtonian fuel oil flowrate. The experimental study was conducted based on a characterization of the rheological behavior of fuel oil and modeling for a pseudoplastic behavior. The resulting model describes temperature changes, viscous friction effects and the effects of blending flow layers; which is therefore the basis of calculation for the selection, evaluation and rationalization of transport of heavy fuel oil by pipelines.
Newman, P. A.; Schoeberl, M. R.; Plumb, R. A.
1986-01-01
Calculations of the two-dimensional, species-independent mixing coefficients for two-dimensional chemical models for the troposphere and stratosphere are performed using quasi-geostrophic potential vorticity fluxes and gradients from 4 years of National Meteorological Center data for the four seasons in both hemispheres. Results show that the horizontal mixing coefficient values for the winter lower stratosphere are broadly consistent with those currently employed in two-dimensional models, but the horizontal mixing coefficient values in the northern winter upper stratosphere are much larger than those usually used.
Directory of Open Access Journals (Sweden)
Grzegorz SZALA
2014-03-01
Full Text Available In the paper there was attempted to analyse models of fatigue life curves possible to apply in calculations of fatigue life of machine elements. The analysis was limited to fatigue life curves in stress approach enabling cyclic stresses from the range of low cycle fatigue (LCF, high cycle fatigue (HCF, fatigue limit (FL and giga cycle fatigue (GCF appearing in the loading spectrum at the same time. Chosen models of the analysed fatigue live curves will be illustrated with test results of steel and aluminium alloys.
Directory of Open Access Journals (Sweden)
Riionheimo Janne
2003-01-01
Full Text Available We describe a technique for estimating control parameters for a plucked string synthesis model using a genetic algorithm. The model has been intensively used for sound synthesis of various string instruments but the fine tuning of the parameters has been carried out with a semiautomatic method that requires some hand adjustment with human listening. An automated method for extracting the parameters from recorded tones is described in this paper. The calculation of the fitness function utilizes knowledge of the properties of human hearing.
Total Sensitivity Index Calculation of Tool Requirement Model via Error Propagation Equation
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
A new and convenient method is presented to calculate the total sensitivity indices defined by variance-based sensitivity analysis. By decomposing the output variance using error propagation equations, this method can transform the "double-loop" sampling procedure into "single-loop" one and obviously reduce the computation cost of analysis. In contrast with Sobol's and Fourier amplitude sensitivity test (FAST) method, which is limited in non-correlated variables, the new approach is suitable for correlated input variables. An application in semiconductor assembling and test manufacturing (ATM) factory indicates that this approach has a good performance in additive model and simple non-additive model.
The truth is out there: measured, calculated and modelled benthic fluxes.
Pakhomova, Svetlana; Protsenko, Elizaveta
2016-04-01
In a modern Earth science there is a great importance of understanding the processes, forming the benthic fluxes as one of element sources or sinks to or from the water body, which affects the elements balance in the water system. There are several ways to assess benthic fluxes and here we try to compare the results obtained by chamber experiments, calculated from porewater distributions and simulated with model. Benthic fluxes of dissolved elements (oxygen, nitrogen species, phosphate, silicate, alkalinity, iron and manganese species) were studied in the Baltic and Black Seas from 2000 to 2005. Fluxes were measured in situ using chamber incubations (Jch) and at the same time sediment cores were collected to assess the porewater distribution at different depths to calculate diffusive fluxes (Jpw). Model study was carried out with benthic-pelagic biogeochemical model BROM (O-N-P-Si-C-S-Mn-Fe redox model). It was applied to simulate biogeochemical structure of the water column and upper sediment and to assess the vertical fluxes (Jmd). By the behaviour at the water-sediment interface all studied elements can be divided into three groups: (1) elements which benthic fluxes are determined by the concentrations gradient only (Si, Mn), (2) elements which fluxes depend on redox conditions in the bottom water (Fe, PO4, NH4), and (3) elements which fluxes are strongly connected with organic matter fate (O2, Alk, NH4). For the first group it was found that measured fluxes are always higher than calculated diffusive fluxes (1.5
Jensen, Lasse; van Duijnen, Piet Th.; Snijders, Jaap G.
2003-12-01
We present a discrete solvent reaction field (DRF) model for the calculation of frequency-dependent hyperpolarizabilities of molecules in solution. In this model the solute is described using density functional theory (DFT) and the discrete solvent molecules are described with a classical polarizable model. The first hyperpolarizability is obtained in an efficient way using time-dependent DFT and the (2n+1) rule. The method was tested for liquid water using a model in which a water molecule is embedded in a cluster of 127 classical water molecules. The frequency-dependent first and second hyperpolarizabilities related to the electric field induced second harmonic generation (EFISH) experiment, were calculated both in the gas phase and in the liquid phase. For water in the gas phase, results are obtained in good agreement with correlated wave function methods and experiments by using the so-called shape-corrected exchange correlation (xc)-potentials. In the liquid phase the effect of using asymptotically correct functionals is discussed. The model reproduced the experimentally observed sign change in the first hyperpolarizaibility when going from the gas phase to the liquid phase. Furthermore, it is shown that the first hyperpolarizability is more sensitive to damping of the solvent-solute interactions at short range than the second hyperpolarizability.
Bodermann, Bernd; Ehret, Gerd
2005-08-01
High resolution optical microscopy is still an important instrument for dimensional characterisation of micro- und nanostructures. For precise measurements of dimensional quantities a highly accurate modelling of the optical imaging on the basis of rigorous diffraction calculation is essential, which accounts for both the polarisation effects and the 2D or 3D geometry of the structures. Some applications like for example the measurements of linewidths on photomasks demands for measurement uncertainties of few nm or less. For these requirements the numerical and the model induced uncertainty, respectively, may be limiting factors even for sophisticated modelling software. At PTB we use two different rigorous grating diffraction models for modelling of the intensity distribution in the image plane, the rigorous coupled wave analysis (RCWA) method and the finite elements (FEM) method. In order to evaluate the performance of both methods we performed comparative calculations on the basis of a test suite of binary chrome on glass gratings with different line widths reaching from 100nm to 10μm, and with different line/space ratios between 0.01 and 100. We present results of this comparison for TE, TM and unpolarised Koehler illumination of the grating. Residual deviations between both methods and the resulting measurement uncertainty and related to the corresponding time consumptions are considered.
Mathematical calculation model for geometrical parameters of timber mesh design with orthogonal grid
Directory of Open Access Journals (Sweden)
Loktev Dmitriy Aleksandrovich
Full Text Available Mesh cover design, a multi-element design, which ensures the correct geometrical arrangement of the elements, is a very important task. The purpose of the given article is the development of a mathematical model for selecting the geometric parameters of wooden arches with mesh orthogonal grid with different input data. In this article three variants of design were observed. The main differences between them are in the relative position of longitudinal and transverse components. When performing static calculations of such designs in order to achieve their subsequent correct assembly, the following location conditions were observed: all the items must strictly match with each other without a gap and without overlap. However, these conditions must be met for any ratio of height to the arch span, the number of longitudinal members and the thickness of longitudinal members. Inverse problems also take place. In this case, the geometric calculation is not possible to vary the cross-section elements, and the stress-strain state of the cover is provided by varying the pitch of the transverse arches of the elements, on which the geometric calculation has no influence. All this determines the need for universal mathematical models describing any geometrical parameter of the designs needed for their geometrical calculation. The basic approach for the development of such models is the use of the known trigonometric formulas, giving a complete description of the desired geometry of the arch. Finally three transcendental equations were obtained, the solution algorithm of which using Newton’s method is presented in the MathCAD. The complexity of solving such equations using the proposed algorithm in the MathCAD is reduced to a minimum.
Use of the FACTS solvation model for protein-ligand docking calculations. Application to EADock.
Zoete, Vincent; Grosdidier, Aurélien; Cuendet, Michel; Michielin, Olivier
2010-01-01
Protein-ligand docking has made important progress during the last decade and has become a powerful tool for drug development, opening the way to virtual high throughput screening and in silico structure-based ligand design. Despite the flattering picture that has been drawn, recent publications have shown that the docking problem is far from being solved, and that more developments are still needed to achieve high successful prediction rates and accuracy. Introducing an accurate description of the solvation effect upon binding is thought to be essential to achieve this goal. In particular, EADock uses the Generalized Born Molecular Volume 2 (GBMV2) solvent model, which has been shown to reproduce accurately the desolvation energies calculated by solving the Poisson equation. Here, the implementation of the Fast Analytical Continuum Treatment of Solvation (FACTS) as an implicit solvation model in small molecules docking calculations has been assessed using the EADock docking program. Our results strongly support the use of FACTS for docking. The success rates of EADock/FACTS and EADock/GBMV2 are similar, i.e. around 75% for local docking and 65% for blind docking. However, these results come at a much lower computational cost: FACTS is 10 times faster than GBMV2 in calculating the total electrostatic energy, and allows a speed up of EADock by a factor of 4. This study also supports the EADock development strategy relying on the CHARMM package for energy calculations, which enables straightforward implementation and testing of the latest developments in the field of Molecular Modeling.
A model for cross-referencing and calculating similarity of metal alloys
Directory of Open Access Journals (Sweden)
Svetlana Pocajt
2013-12-01
Full Text Available This paper presents an innovative model for the comparison and crossreferencing of metal alloys, in order to determine their interchangeability in engineering, manufacturing and material sourcing. The model uses a large alloy database and statistical approach to estimate missing composition and mechanical properties parameters and to calculate property intervals. A classification of metals and fuzzy logic are then applied to compare metal alloys. The model and its algorithm have been implemented and tested in real-life applications. In this paper, an application of the model in finding unknown equivalent metals by comparing their compositions and mechanical properties in a very large metals database is described, and possibilities for further research and new applications are presented.
A computer code for calculations in the algebraic collective model of the atomic nucleus
Welsh, T A
2016-01-01
A Maple code is presented for algebraic collective model (ACM) calculations. The ACM is an algebraic version of the Bohr model of the atomic nucleus, in which all required matrix elements are derived by exploiting the model's SU(1,1) x SO(5) dynamical group. This, in particular, obviates the use of coefficients of fractional parentage. This paper reviews the mathematical formulation of the ACM, and serves as a manual for the code. The code makes use of expressions for matrix elements derived elsewhere and newly derived matrix elements of the operators [pi x q x pi]_0 and [pi x pi]_{LM}, where q_M are the model's quadrupole moments, and pi_N are corresponding conjugate momenta (-2>=M,N<=2). The code also provides ready access to SO(3)-reduced SO(5) Clebsch-Gordan coefficients through data files provided with the code.
Development of an algebraic stress/two-layer model for calculating thrust chamber flow fields
Chen, C. P.; Shang, H. M.; Huang, J.
1993-01-01
Following the consensus of a workshop in Turbulence Modeling for Liquid Rocket Thrust Chambers, the current effort was undertaken to study the effects of second-order closure on the predictions of thermochemical flow fields. To reduce the instability and computational intensity of the full second-order Reynolds Stress Model, an Algebraic Stress Model (ASM) coupled with a two-layer near wall treatment was developed. Various test problems, including the compressible boundary layer with adiabatic and cooled walls, recirculating flows, swirling flows and the entire SSME nozzle flow were studied to assess the performance of the current model. Detailed calculations for the SSME exit wall flow around the nozzle manifold were executed. As to the overall flow predictions, the ASM removes another assumption for appropriate comparison with experimental data, to account for the non-isotropic turbulence effects.
Scheuerell, Mark D
2016-01-01
Stock-recruitment models have been used for decades in fisheries management as a means of formalizing the expected number of offspring that recruit to a fishery based on the number of parents. In particular, Ricker's stock recruitment model is widely used due to its flexibility and ease with which the parameters can be estimated. After model fitting, the spawning stock size that produces the maximum sustainable yield (S MSY) to a fishery, and the harvest corresponding to it (U MSY), are two of the most common biological reference points of interest to fisheries managers. However, to date there has been no explicit solution for either reference point because of the transcendental nature of the equation needed to solve for them. Therefore, numerical or statistical approximations have been used for more than 30 years. Here I provide explicit formulae for calculating both S MSY and U MSY in terms of the productivity and density-dependent parameters of Ricker's model.
Institute of Scientific and Technical Information of China (English)
ZHAO Xinyu; GANG Tie; ZHANG Bixing
2009-01-01
A nonparaxial multi-Gaussian beam model based on the rectangular aperture is proposed in order to overcome the hmitation of paraxial Gaussian beam model which losing accuracy in off-axis beam fields. With the method, acoustical field generated by an ultra-sonic linear phased array transducer is calculated and compared with the corresponding field obtained by Rayleigh-Sommerfeld integral, paraxial multi-Gaussian beam model, and Fraunhof-fer approximation method. Simulation examples show that nonparaxial multi-Gaussian beam model is not limited by the paraxial approximation condition and can predict efficiently and accurately the acoustical field radiated by a linear phased array transducer over a wide range of steering angles.
Kim, Kwang Hyeon; Lee, Suk; Shim, Jang Bo; Chang, Kyung Hwan; Yang, Dae Sik; Yoon, Won Sup; Park, Young Je; Kim, Chul Yong; Cao, Yuan Jie
2017-08-01
The aim of this study is an integrated research for text-based data mining and toxicity prediction modeling system for clinical decision support system based on big data in radiation oncology as a preliminary research. The structured and unstructured data were prepared by treatment plans and the unstructured data were extracted by dose-volume data image pattern recognition of prostate cancer for research articles crawling through the internet. We modeled an artificial neural network to build a predictor model system for toxicity prediction of organs at risk. We used a text-based data mining approach to build the artificial neural network model for bladder and rectum complication predictions. The pattern recognition method was used to mine the unstructured toxicity data for dose-volume at the detection accuracy of 97.9%. The confusion matrix and training model of the neural network were achieved with 50 modeled plans (n = 50) for validation. The toxicity level was analyzed and the risk factors for 25% bladder, 50% bladder, 20% rectum, and 50% rectum were calculated by the artificial neural network algorithm. As a result, 32 plans could cause complication but 18 plans were designed as non-complication among 50 modeled plans. We integrated data mining and a toxicity modeling method for toxicity prediction using prostate cancer cases. It is shown that a preprocessing analysis using text-based data mining and prediction modeling can be expanded to personalized patient treatment decision support based on big data.
S/sup 3/ Financial Projection Model: preliminary user's manual and system overview
Energy Technology Data Exchange (ETDEWEB)
Masso, J. F.
1976-11-30
The S/sup 3/ Financial Projection Model is an effort undertaken to construct a pipeline economic model in order to satisfy the requirements of the US ERDA program: Energy Study of Pipeline Transportation System. A brief outline of this process is described in Appendix A, Background on the S/sup 3/ Development of a Pipeline Economic Model. A general overview of the model is presented first to indicate the rationale underlying the model and to show the linkages between the various submodels. An understanding of the basic accounting definitions and self-evident relationships between line items in the general financial accounting reports is a prerequisite for the effective application of the model. Particular attention has been paid in this system description to defining the methods of calculations utilized by the model and to describing the optional capital investment planning techniques that may be exercised with the model. The mathematical relationships underlying various planning techniques are defined and the methods for applying these techniques are discussed with illustrations and sample input data specifications. Decision tables are used to show complex decision rules applied within the model to determine the logical flow of a particular computational routine. The complete set of source data and model options are described along with the procedures for input data preparation and actual program operation.
Development of sump model for containment hydrogen distribution calculations using CFD code
Energy Technology Data Exchange (ETDEWEB)
Ravva, Srinivasa Rao, E-mail: srini@aerb.gov.in [Indian Institute of Technology-Bombay, Mumbai (India); Nuclear Safety Analysis Division, Atomic Energy Regulatory Board, Mumbai (India); Iyer, Kannan N. [Indian Institute of Technology-Bombay, Mumbai (India); Gaikwad, A.J. [Nuclear Safety Analysis Division, Atomic Energy Regulatory Board, Mumbai (India)
2015-12-15
Highlights: • Sump evaporation model was implemented in FLUENT using three different approaches. • Validated the implemented sump evaporation models against TOSQAN facility. • It was found that predictions are in good agreement with the data. • Diffusion based model would be able to predict both condensation and evaporation. - Abstract: Computational Fluid Dynamics (CFD) simulations are necessary for obtaining accurate predictions and local behaviour for carrying out containment hydrogen distribution studies. However, commercially available CFD codes do not have all necessary models for carrying out hydrogen distribution analysis. One such model is sump or suppression pool evaporation model. The water in the sump may evaporate during the accident progression and affect the mixture concentrations in the containment. Hence, it is imperative to study the sump evaporation and its effect. Sump evaporation is modelled using three different approaches in the present work. The first approach deals with the calculation of evaporation flow rate and sump liquid temperature and supplying these quantities through user defined functions as boundary conditions. In this approach, the mean values of the domain are used. In the second approach, the mass, momentum, energy and species sources arise due to the sump evaporation are added to the domain through user defined functions. Cell values adjacent to the sump interface are used in this. Heat transfer between gas and liquid is calculated automatically by the code itself. However, in these two approaches, the evaporation rate was computed using an experimental correlation. In the third approach, the evaporation rate is directly estimated using diffusion approximation. The performance of these three models is compared with the sump behaviour experiment conducted in TOSQAN facility.Classification: K. Thermal hydraulics.
Preliminary clinical nursing leadership competency model: a qualitative study from Thailand.
Supamanee, Treeyaphan; Krairiksh, Marisa; Singhakhumfu, Laddawan; Turale, Sue
2011-12-01
This qualitative study explored the clinical nursing leadership competency perspectives of Thai nurses working in a university hospital. To collect data, in-depth interviews were undertaken with 23 nurse administrators, and focus groups were used with 31 registered nurses. Data were analyzed using content analysis, and theory development was guided by the Iceberg model. Nurses' clinical leadership competencies emerged, comprising hidden characteristics and surface characteristics. The hidden characteristics composed three elements: motive (respect from the nursing and healthcare team and being secure in life), self-concept (representing positive attitudes and values), and traits (personal qualities necessary for leadership). The surface characteristics comprised specific knowledge of nurse leaders about clinical leadership, management and nursing informatics, and clinical skills, such as coordination, effective communication, problem solving, and clinical decision-making. The study findings help nursing to gain greater knowledge of the essence of clinical nursing leadership competencies, a matter critical for theory development in leadership. This study's results later led to the instigation of a training program for registered nurse leaders at the study site, and the formation of a preliminary clinical nursing leadership competency model.
Preliminary scenarios and nuclide transport models for low-and intermediate-level repository system
Energy Technology Data Exchange (ETDEWEB)
Lee, Youn Myoung; Han, Kyong Won; Hwang, Yong Soo; Kang, Chul Hyung
2001-02-01
Through the study 11 scenarios with which nuclide release from the low- and intermediate-level radioactive waste could be simulated and assessed are selected, based upon FEPs identified. For each scenario, some practical methodologies as well as mathematical models involved in modling of nuclide transport in various media are also proposed. It is considered that such methodologies can play a great role when real repository system is constructed and operated in very near future. Real repository system is anticipated not to be quite different with the repository system postulated through this study. Even though there shows very complicated features for relevant parameters associated with various phisical-, geohydrological-, and geochemical situation and even human society as well, it is very necessary to propose the methodologies for a quantitative assessment of the performance of the repository in order to use them as a template on the practical point of view of preliminary safety assessment. Mathematical models proposed could be easily adopted by such common computer codes as, for example, MIMOSA and MASCOT-K.
Energy Technology Data Exchange (ETDEWEB)
Chae, Hee Taek; Park, Jong Hark; Park, Cheol
2006-11-15
A new research reactor (AHR, Advanced HANARO Reactor) based on the HANARO has being conceptually developed for the future needs of research reactors. A tubular type fuel was considered as one of the fuel options of the AHR. A tubular type fuel assembly has several curved fuel plates arranged with a constant small gap to build up cooling channels, which is very similar to an annulus pipe with many layers. This report presents the preliminary analysis of thermal hydraulic characteristics and safety margins for three conceptual core models using tubular fuel assemblies. Four design criteria, which are the fuel temperature, ONB (Onset of Nucleate Boiling) margin, minimum DNBR (Departure from Nucleate Boiling Ratio) and OFIR (Onset of Flow Instability Ratio), were investigated along with various core flow velocities in the normal operating conditions. And the primary coolant flow rate based a conceptual core model was suggested as a design information for the process design of the primary cooling system. The computational fluid dynamics analysis was also carried out to evaluate the coolant velocity distributions between tubular channels and the pressure drop characteristics of the tubular fuel assembly.
Planning Genomic Study in an Animal Model of Depression: a Preliminary Report
Directory of Open Access Journals (Sweden)
Sara Farhang
2011-09-01
Full Text Available Introduction: Interaction of several genes is responsible for psychiatric diseases such as depression. Despite the numerous microarray studies in this field, findings are controversial and hard to conclude. Methods: Male Wistar rats were randomly selected to receive Chronic Mild Stress model for 4 weeks. Different aspects of depression were measured by forced swimming test, open field trial and sucrose preference tests in the experience group and controls. Results: Sucrose was preferred by 40% of CMS group and 80% of controls (p=0.025. Twenty percent of CMS group and 80% of controls were “active” (p=0.001. Last escape was at minute 238 for CMS group and minute 245 for controls and controls had more escape efforts. Conclusion: This paper is a preliminary report of a genomic study on animal model of depression which tries to achieve reliable results by a joint of clinical view with recent techniques. Predicted challenges in this procedure and the solutions as well as the limitations may be helpful for future researches.
de Souza Aranha E Silva, Renata Almeida; Baltieri, Danilo Antonio
2016-01-01
Although zoophilic blogs and websites attract the attention of zoophiles and others who are curious about this sexual activity, the motivations for consuming this type of pornography are not clear. This study aimed to confirm the factorial validity of the Pornography Consumption Inventory in an online sample of men with sexual interest in animals, and to construct an association model between motivations for pornography consumption and the following psychological variables: depression, sexual impulsiveness, and strength of sexual interest in animals. In this cross-sectional study, we located a website that catered to a network of people with a sexual interest in animals. Subsequently, a questionnaire was made available online to members of this network. Results support the 4-factor model of the Pornography Consumption Inventory. Depression and strength of sexual interest in animals were negatively and positively correlated with the sexual curiosity factor, respectively. Sexual impulsiveness was positively associated with the emotional avoidance, excitement seeking, and sexual pleasure factors. Depression and sexual impulsiveness were positively correlated. Psychological factors can differently motivate the consumption of pornography among men who visit zoophilic blogs and websites. With these preliminary data, we can identify some characteristics of this population.
Animation model of Krsko nuclear power plant for RELAP5 calculations
Energy Technology Data Exchange (ETDEWEB)
Prosek, Andrej, E-mail: andrej.prosek@ijs.s [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Mavko, Borut [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)
2011-04-15
Today most software applications, also in the nuclear field, come with a graphical user interface. The first graphical user interface for the RELAP5 thermal-hydraulic computer code was called the Nuclear Plant Analyzer (NPA). Later, Symbolic Nuclear Analysis Package (SNAP) was developed. The purpose of the present study was to develop SNAP animation model of Krsko nuclear power plant (NPP) for RELAP5 calculations with the aim to help analyze the results. In addition, the reference calculations for Krsko full scope simulator validation were performed with the latest RELAP5/MOD3.3 Patch 03 code and compared to previous RELAP5 versions to provide verified source data, needed to demonstrate animation model. In total six scenarios were analyzed: two scenarios of the small-break loss-of-coolant accident, two scenarios of the loss of main feedwater, a scenario of the anticipated transient without scram, and a scenario of the steam generator tube rupture. The use of SNAP for animation of Krsko nuclear power plant analyses showed several benefits, especially better understanding of the calculated physical phenomena and processes. It can be concluded that an animation tool was created, which enables to analyze very complex accident scenarios. The graphical surface helps keeping the overview and focusing on the main influences. Also, the use of such support tools to system codes may significantly contribute to better quality of safety analysis.
Institute of Scientific and Technical Information of China (English)
Wu Qiong; Li Shu-Suo; Ma Yue; Gong Sheng-Kai
2012-01-01
The diffusion coefficients of several alloying elements (Al,Mo,Co,Ta,Ru,W,Cr,Re) in Ni are directly calculated using the five-frequency model and the first principles density functional theory.The correlation factors provided by the five-frequency model are explicitly calculated.The calculated diffusion coefficients show their excellent agreement with the available experimental data.Both the diffusion pre-factor (Do) and the activation energy (Q) of impurity diffusion are obtained.The diffusion coefficients above 700 K are sorted in the following order:DAl ＞ DCr ＞ DCo ＞ DTa ＞DMo ＞ DRu ＞ DW ＞ DRe.It is found that there is a positive correlation between the atomic radius of the solute and the jump energy of Ni that results in the rotation of the solute-vacancy pair (E1).The value of E2-E1 (E2 is the solute diffusion energy) and the correlation factor each also show a positive correlation.The larger atoms in the same series have lower diffusion activation energies and faster diffusion coefficients.
MODELING AND CALCULATION OF FLOW AMPLIFIER PARAMETERS IN STEERING OF HEAVY TRUCKS
Directory of Open Access Journals (Sweden)
V. P. Avtushko
2008-01-01
Full Text Available The paper analyzes prospects pertaining to development of methods for dynamic calculation of monitoring hydraulic units with various types of relations. Calculated diagram of steering hydraulic drive with flow amplifier and turning cylinder has been given in the paper and its dynamic model has been developed. A hydraulic drive is considered as a system with lumped parameters. It is supposed that properties of working fluid are unchangeable during transient process; leakages and cavitations do not occur; fluid can be pressed; resistance of service drain line is taken into account. Model has been developed with due account of resistance of manifolds and internal channels of flow amplifier, hydrodynamic forces, that influence on amplifier control valves, and friction forces of movable elements. Multi-variant dynamic calculation has been done and some results of the investigations are presented in the paper. The paper also contains analysis that shows influence of various design and component parameters of flow amplifier on the drive dynamics.
Model-based dose calculations for {sup 125}I lung brachytherapy
Energy Technology Data Exchange (ETDEWEB)
Sutherland, J. G. H.; Furutani, K. M.; Garces, Y. I.; Thomson, R. M. [Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States); Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada)
2012-07-15
Purpose: Model-baseddose calculations (MBDCs) are performed using patient computed tomography (CT) data for patients treated with intraoperative {sup 125}I lung brachytherapy at the Mayo Clinic Rochester. Various metallic artifact correction and tissue assignment schemes are considered and their effects on dose distributions are studied. Dose distributions are compared to those calculated under TG-43 assumptions. Methods: Dose distributions for six patients are calculated using phantoms derived from patient CT data and the EGSnrc user-code BrachyDose. {sup 125}I (GE Healthcare/Oncura model 6711) seeds are fully modeled. Four metallic artifact correction schemes are applied to the CT data phantoms: (1) no correction, (2) a filtered back-projection on a modified virtual sinogram, (3) the reassignment of CT numbers above a threshold in the vicinity of the seeds, and (4) a combination of (2) and (3). Tissue assignment is based on voxel CT number and mass density is assigned using a CT number to mass density calibration. Three tissue assignment schemes with varying levels of detail (20, 11, and 5 tissues) are applied to metallic artifact corrected phantoms. Simulations are also performed under TG-43 assumptions, i.e., seeds in homogeneous water with no interseed attenuation. Results: Significant dose differences (up to 40% for D{sub 90}) are observed between uncorrected and metallic artifact corrected phantoms. For phantoms created with metallic artifact correction schemes (3) and (4), dose volume metrics are generally in good agreement (less than 2% differences for all patients) although there are significant local dose differences. The application of the three tissue assignment schemes results in differences of up to 8% for D{sub 90}; these differences vary between patients. Significant dose differences are seen between fully modeled and TG-43 calculations with TG-43 underestimating the dose (up to 36% in D{sub 90}) for larger volumes containing higher proportions of
A double-step truncation procedure for large-scale shell-model calculations
Coraggio, L; Itaco, N
2016-01-01
We present a procedure that is helpful to reduce the computational complexity of large-scale shell-model calculations, by preserving as much as possible the role of the rejected degrees of freedom in an effective approach. Our truncation is driven first by the analysis of the effective single-particle energies of the original large-scale shell-model hamiltonian, so to locate the relevant degrees of freedom to describe a class of isotopes or isotones, namely the single-particle orbitals that will constitute a new truncated model space. The second step is to perform an unitary transformation of the original hamiltonian from its model space into the truncated one. This transformation generates a new shell-model hamiltonian, defined in a smaller model space, that retains effectively the role of the excluded single-particle orbitals. As an application of this procedure, we have chosen a realistic shell-model hamiltonian defined in a large model space, set up by seven and five proton and neutron single-particle orb...
A Comparison of Model Calculation and Measurement of Absorbed Dose for Proton Irradiation. Chapter 5
Zapp, N.; Semones, E.; Saganti, P.; Cucinotta, F.
2003-01-01
With the increase in the amount of time spent EVA that is necessary to complete the construction and subsequent maintenance of ISS, it will become increasingly important for ground support personnel to accurately characterize the radiation exposures incurred by EVA crewmembers. Since exposure measurements cannot be taken within the organs of interest, it is necessary to estimate these exposures by calculation. To validate the methods and tools used to develop these estimates, it is necessary to model experiments performed in a controlled environment. This work is such an effort. A human phantom was outfitted with detector equipment and then placed in American EMU and Orlan-M EVA space suits. The suited phantom was irradiated at the LLUPTF with proton beams of known energies. Absorbed dose measurements were made by the spaceflight operational dosimetrist from JSC at multiple sites in the skin, eye, brain, stomach, and small intestine locations in the phantom. These exposures are then modeled using the BRYNTRN radiation transport code developed at the NASA Langley Research Center, and the CAM (computerized anatomical male) human geometry model of Billings and Yucker. Comparisons of absorbed dose calculations with measurements show excellent agreement. This suggests that there is reason to be confident in the ability of both the transport code and the human body model to estimate proton exposure in ground-based laboratory experiments.
Ernren, A.T.; Arthur, R.; Glynn, P.D.; McMurry, J.
1999-01-01
Four researchers were asked to provide independent modeled estimates of the solubility of a radionuclide solid phase, specifically Pu(OH)4, under five specified sets of conditions. The objectives of the study were to assess the variability in the results obtained and to determine the primary causes for this variability.In the exercise, modelers were supplied with the composition, pH and redox properties of the water and with a description of the mineralogy of the surrounding fracture system A standard thermodynamic data base was provided to all modelers. Each modeler was encouraged to use other data bases in addition to the standard data base and to try different approaches to solving the problem.In all, about fifty approaches were used, some of which included a large number of solubility calculations. For each of the five test cases, the calculated solubilities from different approaches covered several orders of magnitude. The variability resulting from the use of different thermodynamic data bases was in most cases, far smaller than that resulting from the use of different approaches to solving the problem.
Energy Technology Data Exchange (ETDEWEB)
Madni, I.K. [Brookhaven National Lab., Upton, NY (United States); Cazzoli, E.G.; Khatib-Rahbar, M. [Energy Research, Inc., Rockville, MD (United States)
1995-11-01
During certain hypothetical severe accidents in a nuclear power plant, radionuclides could be released to the environment as a plume. Prediction of the atmospheric dispersion and transport of these radionuclides is important for assessment of the risk to the public from such accidents. A simplified PC-based model was developed that predicts time-integrated air concentration of each radionuclide at any location from release as a function of time integrated source strength using the Gaussian plume model. The solution procedure involves direct analytic integration of air concentration equations over time and position, using simplified meteorology. The formulation allows for dry and wet deposition, radioactive decay and daughter buildup, reactor building wake effects, the inversion lid effect, plume rise due to buoyancy or momentum, release duration, and grass height. Based on air and ground concentrations of the radionuclides, the early dose to an individual is calculated via cloudshine, groundshine, and inhalation. The model also calculates early health effects based on the doses. This paper presents aspects of the model that would be of interest to the prediction of environmental flows and their public consequences.
Calculations of inflaton decays and reheating: with applications to no-scale inflation models
Energy Technology Data Exchange (ETDEWEB)
Ellis, John [Theoretical Particle Physics and Cosmology Group, Department of Physics,King’s College London,London WC2R 2LS (United Kingdom); Theory Division, CERN,CH-1211 Geneva 23 (Switzerland); Garcia, Marcos A.G. [William I. Fine Theoretical Physics Institute, School of Physics and Astronomy,University of Minnesota,116 Church Street SE, Minneapolis, MN 55455 (United States); Nanopoulos, Dimitri V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Texas A& M University,College Station, 77843 Texas (United States); Astroparticle Physics Group, Houston Advanced Research Center (HARC), Mitchell Campus, Woodlands, 77381 Texas (United States); Academy of Athens, Division of Natural Sciences,28 Panepistimiou Avenue, Athens 10679 (Greece); Olive, Keith A. [William I. Fine Theoretical Physics Institute, School of Physics and Astronomy,University of Minnesota,116 Church Street SE, Minneapolis, MN 55455 (United States)
2015-07-30
We discuss inflaton decays and reheating in no-scale Starobinsky-like models of inflation, calculating the effective equation-of-state parameter, w, during the epoch of inflaton decay, the reheating temperature, T{sub reh}, and the number of inflationary e-folds, N{sub ∗}, comparing analytical approximations with numerical calculations. We then illustrate these results with applications to models based on no-scale supergravity and motivated by generic string compactifications, including scenarios where the inflaton is identified as an untwisted-sector matter field with direct Yukawa couplings to MSSM fields, and where the inflaton decays via gravitational-strength interactions. Finally, we use our results to discuss the constraints on these models imposed by present measurements of the scalar spectral index n{sub s} and the tensor-to-scalar perturbation ratio r, converting them into constraints on N{sub ∗}, the inflaton decay rate and other parameters of specific no-scale inflationary models.
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed. The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope. The lateral displacement of frame and soil is nearly in phase. The movement characteristic satisfies the theory of elastic foundation beam. The frame is treated with elastic foundation beam in this model. The influence of prestressed anchors is simplified as linear spring and damped system related with velocity. Under the condition of horizontal earthquake excitation, the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration. This method is applied to a case record for illustration of its capability, in order to verify the method, 3D nonlinear FEM (ADINA) is used to analyze the seismic performance of this case, the comparative results show that the design and the analysis are safe and credible by using the proposed method. The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.
Preliminary results from a four-working space, double-acting piston, Stirling engine controls model
Daniele, C. J.; Lorenzo, C. F.
1980-01-01
A four working space, double acting piston, Stirling engine simulation is being developed for controls studies. The development method is to construct two simulations, one for detailed fluid behavior, and a second model with simple fluid behaviour but containing the four working space aspects and engine inertias, validate these models separately, then upgrade the four working space model by incorporating the detailed fluid behaviour model for all four working spaces. The single working space (SWS) model contains the detailed fluid dynamics. It has seven control volumes in which continuity, energy, and pressure loss effects are simulated. Comparison of the SWS model with experimental data shows reasonable agreement in net power versus speed characteristics for various mean pressure levels in the working space. The four working space (FWS) model was built to observe the behaviour of the whole engine. The drive dynamics and vehicle inertia effects are simulated. To reduce calculation time, only three volumes are used in each working space and the gas temperature are fixed (no energy equation). Comparison of the FWS model predicted power with experimental data shows reasonable agreement. Since all four working spaces are simulated, the unique capabilities of the model are exercised to look at working fluid supply transients, short circuit transients, and piston ring leakage effects.
Energy Technology Data Exchange (ETDEWEB)
RAST RS; RINKER MW; BAPANAALLI SK; DEIBLER JE; GUZMAN-LEONG CE; JOHNSON KI; KARRI NK; PILLI SP; SANBORN SE
2010-10-22
This document is a Phase I deliverable for the Single-Shell Tank Analysis of Record effort. This document is not the Analysis of Record. The intent of this document is to guide the Phase II detailed modeling effort. Preliminary finite element models for each of the tank types were developed and different case studies were performed on one or more of these tank types. Case studies evaluated include thermal loading, waste level variation, the sensitivity of boundary effects (soil radial extent), excavation slope or run to rise ratio, soil stratigraphic (property and layer thickness) variation at different farm locations, and concrete material property variation and their degradation under thermal loads. The preliminary analysis document reviews and preliminary modeling analysis results are reported herein. In addition, this report provides recommendations for the next phase of the SST AOR project, SST detailed modeling. Efforts and results discussed in this report do not include seismic modeling as seismic modeling is covered by a separate report. The combined results of both static and seismic models are required to complete this effort. The SST AOR project supports the US Department of Energy's (DOE) Office of River Protection (ORP) mission for obtaining a better understanding of the structural integrity of Hanford's SSTs. The 149 SSTs, with six different geometries, have experienced a range of operating histories which would require a large number of unique analyses to fully characterize their individual structural integrity. Preliminary modeling evaluations were conducted to determine the number of analyses required for adequate bounding of each of the SST tank types in the Detailed Modeling Phase of the SST AOR Project. The preliminary modeling was conducted in conjunction with the Evaluation Criteria report, Johnson et al. (2010). Reviews of existing documents were conducted at the initial stage of preliminary modeling. These reviews guided the topics
Quantum chemical calculations using the Floating Point Systems, Inc. Model 164 attached processor
Energy Technology Data Exchange (ETDEWEB)
Shepard, R.; Bair, R.A.; Eades, R.A.; Wagner, A.F.; Davis, M.J.; Harding, L.B.; Dunning, T.H. Jr.
1983-01-01
The Theoretical Chemistry Group at Argonne National Laboratory has had a Floating Point System, Inc., Model 164 Attached Processor (FPS-164) for several months. Actual production calculations, as well as benchmark calculations, indicate that the FPS-164 is capable of performance comparable to large mainframe computers, the groups experience with the FPS-164 includes the conversion of a complete system of electronic structure codes, including integral evaluation programs, generalized valence bond programs, integral transformation programs, and unitary group configuration interaction programs, and two classical trajectory codes. Timings of these programs at various levels of optimization along with estimates of the amount of effort required to make the necessary program modifications are discussed. 10 references, 2 figures, 2 tables.
Testing the spin-cutoff parameterization with shell-model calculations
Spinella, William M
2013-01-01
The nuclear level density, an important input to Hauser-Feshbach calculations, depends not only on excitation energy but also on angular momentum J. The J-dependence of the level density at fixed excitation energy E_x is usually parameterized via the spin-cutoff factor sigma. We carefully test the statistical accuracy of this parameterization for a large number of spectra computed using semi-realistic interactions in the interacting shell model, with a nonlinear least-squares fit of sigma and finding the error bar in sigma. The spin-cutoff parameterization works well as long as there are enough states to be statistical. In turn, the spin-cutoff factor can be related to the average value of J^2 at a fixed excitation energy, and we briefly investigate extracting from a thermal calculation such as one might do via Monte Carlo.
Large scale shell model calculations for even-even $^{62-66}$Fe isotopes
Srivastava, P C
2009-01-01
The recently measured experimental data of Legnaro National Laboratories on neutron rich even isotopes of $^{62-66}$Fe with A=62,64,66 have been interpreted in the framework of large scale shell model. Calculations have been performed with a newly derived effective interaction GXPF1A in full $\\it{fp}$ space without truncation. The experimental data is very well explained for $^{62}$Fe, satisfactorily reproduced for $^{64}$Fe and poorly fitted for $^{66}$Fe. The increasing collectivity reflected in experimental data when approaching N=40 is not reproduced in calculated values. This indicates that whereas the considered valence space is adequate for $^{62}$Fe, inclusion of higher orbits from $\\it{sdg}$ shell is required for describing $^{66}$Fe.
An equivalent circuit model and power calculations for the APS SPX crab cavities.
Energy Technology Data Exchange (ETDEWEB)
Berenc, T. (Accelerator Systems Division (APS))
2012-03-21
An equivalent parallel resistor-inductor-capacitor (RLC) circuit with beam loading for a polarized TM110 dipole-mode cavity is developed and minimum radio-frequency (rf) generator requirements are calculated for the Advanced Photon Source (APS) short-pulse x-ray (SPX) superconducting rf (SRF) crab cavities. A beam-loaded circuit model for polarized TM110 mode crab cavities was derived. The single-cavity minimum steady-state required generator power has been determined for the APS SPX crab cavities for a storage ring current of 200mA DC current as a function of external Q for various vertical offsets including beam tilt and uncontrollable detuning. Calculations to aid machine protection considerations were given.
Modeling and Calculation of Impact Friction Caused by Corner Contact in Gear Transmission
Institute of Scientific and Technical Information of China (English)
ZHOU Changjiang; CHEN Siyu
2014-01-01
Corner contact in gear pair causes vibration and noise, which has attracted many attentions. However, teeth errors and deformation make it difficulty to determine the point situated at corner contact and study the mechanism of teeth impact friction in the current researches. Based on the mechanism of corner contact, the process of corner contact is divided into two stages of impact and scratch, and the calculation model including gear equivalent error-combined deformation is established along the line of action. According to the distributive law, gear equivalent error is synthesized by base pitch error, normal backlash and tooth profile modification on the line of action. The combined tooth compliance of the first point lying in corner contact before the normal path is inversed along the line of action, on basis of the theory of engagement and the curve of tooth synthetic compliance & load-history. Combined secondarily the equivalent error with the combined deflection, the position standard of the point situated at corner contact is probed. Then the impact positions and forces, from the beginning to the end during corner contact before the normal path, are calculated accurately. Due to the above results, the lash model during corner contact is founded, and the impact force and frictional coefficient are quantified. A numerical example is performed and the averaged impact friction coefficient based on the presented calculation method is validated. This research obtains the results which could be referenced to understand the complex mechanism of teeth impact friction and quantitative calculation of the friction force and coefficient, and to gear exact design for tribology.
Directory of Open Access Journals (Sweden)
Silvio Jorge C. Simões
2013-08-01
Full Text Available In different regions of Brazil, population growth and economic development can degrade water quality, compromising watershed health and human supply. Because of its ability to combine spatial and temporal data in the same environment and to create water resources management (WRM models, the Geographical Information System (GIS is a powerful tool for managing water resources, preventing floods and estimating water supply. This paper discusses the integration between GIS and hydrological models and presents a case study relating to the upper section of the Paraíba do Sul Basin (Sao Paulo State portion, situated in the Southeast of Brazil. The case study presented in this paper has a database suitable for the basin’s dimensions, including digitized topographic maps at a 50,000 scale. From an ArcGIS®/ArcHydro Framework Data Model, a geometric network was created to produce different raster products. This first grid derived from the digital elevation model grid (DEM is the flow direction map followed by flow accumulation, stream and catchment maps. The next steps in this research are to include the different multipurpose reservoirs situated along the Paraíba do Sul River and to incorporate rainfall time series data in ArcHydro to build a hydrologic data model within a GIS environment in order to produce a comprehensive spatial temporal model.
Preliminary Evaluation of the DUSTRAN Modeling Suite for Modeling Atmospheric Chloride Transport
Energy Technology Data Exchange (ETDEWEB)
Jensen, Philip; Tran, Tracy; Fritz, Bradley; Rutz, Frederick; Ross, Steven; Gorton, Alicia; Devanathan, Ram; Plante, Paul; Trainor, Kevin
2016-05-03
This study investigates the potential of DUSTRAN, a dust dispersion modeling system developed by Pacific Northwest National Laboratory, to model the transport of sea salt aerosols (SSA). Results from DUSTRAN simulations run with historical meteorological data were compared against privately-measured chloride data at the near coastal Maine Yankee Nuclear Power Plant (NPP) and the Environmental Protection Agency-measured CASTNET data from Acadia National Park (NP). The comparisons have provided both encouragement as to the practical value of DUSTRAN’s CALPUFF model and suggestions for further software development opportunities. All modeled concentrations were within one order of magnitude of those measured and a few test cases showed excellent agreement between modeled and measured concentrations. However, there is a lack of consistency in discrepancy which may be due to inaccurate extrapolation of meteorological data, underlying model physics, and the source term. Future research will refine the software to better capture physical phenomena. Overall, results indicate that with parameter refinement, DUSTRAN has the potential to simulate atmospheric chloride transport from known sources to inland sites for the purpose of determining the corrosion susceptibility of various structures, systems, and components at the site.
Theoretical modeling of zircon's crystal morphology according to data of atomistic calculations
Gromalova, Natalia; Nikishaeva, Nadezhda; Eremin, Nikolay
2017-04-01
Zircon is an essential mineral that is used in the U-Pb dating. Moreover, zircon is highly resistant to radioactive exposure. It is of great interest in solving both fundamental and applied problems associated with the isolation of high-level radioactive waste. There is significant progress in forecasting of the most energetically favorable crystal structures at the present time. Unfortunately, the theoretical forecast of crystal morphology at high technological level is under-explored nowadays, though the estimation of crystal equilibrium habit is extremely important in studying the physical and chemical properties of new materials. For the first time, the thesis about relation of the equilibrium shape of a crystal with its crystal structure was put forward in the works by O.Brave. According to it, the idealized habit is determined in the simplest case by a correspondence with the reticular densities Rhkl of individual faces. This approach, along with all subsequent corrections, does not take into account the nature of atoms and the specific features of the chemical bond in crystals. The atomistic calculations of crystal surfaces are commonly performed using the energetic characteristics of faces, namely, the surface energy (Esurf), which is a measure of the thermodynamic stability of the crystal face. The stable crystal faces are characterized by small positive values of Esurf. As we know from our previous research (Gromalova et al.,2015) one of the constitutive factors affecting the value of the surface energy in calculations is a choice of potentials model. In this regard, we studied several sets of parameters of atomistic interatomic potentials optimized previously. As the first test model («Zircon 1») were used sets of interatomic potentials of interaction Zr-O, Si-O and O-O in the form of Buckingham potentials. To improve playback properties of zircon additionally used Morse potential for a couple of Zr-Si, as well as the three-particle angular harmonic
Calculating the renormalisation group equations of a SUSY model with Susyno
Fonseca, Renato M.
2012-10-01
Susyno is a Mathematica package dedicated to the computation of the 2-loop renormalisation group equations of a supersymmetric model based on any gauge group (the only exception being multiple U(1) groups) and for any field content. Program summary Program title: Susyno Catalogue identifier: AEMX_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEMX_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 30829 No. of bytes in distributed program, including test data, etc.: 650170 Distribution format: tar.gz Programming language: Mathematica 7 or higher. Computer: All systems that Mathematica 7+ is available for (PC, Mac). Operating system: Any platform supporting Mathematica 7+ (Windows, Linux, Mac OS). Classification: 4.2, 5, 11.1. Nature of problem: Calculating the renormalisation group equations of a supersymmetric model involves using long and complicated general formulae [1, 2]. In addition, to apply them it is necessary to know the Lagrangian in its full form. Building the complete Lagrangian of models with small representations of SU(2) and SU(3) might be easy but in the general case of arbitrary representations of an arbitrary gauge group, this task can be hard, lengthy and error prone. Solution method: The Susyno package uses group theoretical functions to calculate the super-potential and the soft-SUSY-breaking Lagrangian of a supersymmetric model, and calculates the two-loop RGEs of the model using the general equations of [1, 2]. Susyno works for models based on any representation(s) of any gauge group (the only exception being multiple U(1) groups). Restrictions: As the program is based on the formalism of [1, 2], it shares its limitations. Running time can also be a significant restriction, in particular for models with many fields. Unusual features
Abramopoulos, F.; Rosenzweig, C.; Choudhury, B.
1988-01-01
A physically based ground hydrology model is presented that includes the processes of transpiration, evaporation from intercepted precipitation and dew, evaporation from bare soil, infiltration, soil water flow, and runoff. Data from the Goddard Institute for Space Studies GCM were used as inputs for off-line tests of the model in four 8 x 10 deg regions, including Brazil, Sahel, Sahara, and India. Soil and vegetation input parameters were caculated as area-weighted means over the 8 x 10 deg gridbox; the resulting hydrological quantities were compared to ground hydrology model calculations performed on the 1 x 1 deg cells which comprise the 8 x 10 deg gridbox. Results show that the compositing procedure worked well except in the Sahel, where low soil water levels and a heterogeneous land surface produce high variability in hydrological quantities; for that region, a resolution better than 8 x 10 deg is needed.
Model calculations of edge dislocation defects and vacancies in {alpha}-Iron lattice
Energy Technology Data Exchange (ETDEWEB)
Petrov, L; Troev, T; Nankov, N; Popov, E, E-mail: lpetrov@inrne.bas.b [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia (Bulgaria)
2010-01-01
Two models of defects in perfect {alpha}-iron lattice were discussed. In the perfect bcc iron lattice 42x42x42 a{sub o} (a{sub o} = 2,87 A) an edge dislocation was created, moving the second half of the bulk on one a{sub o} distance. This action generates a little volume in the middle of the bulk witch increases of the positron lifetime (PLT) calculated using the superimposed-atom method of Puska and Nieminen [1]. The result of 118 ps PLT in simple edge dislocation's model is in a good concurrence with earlier publications and experimental data [2]. Through the dislocation line one, two and three vacancies were localized. These models give the results for PLT of 146, 157 and 167 ps respectively. The computer simulations were performed using Finnis-Sinclair (FS) N-body potential.
Large uncertainty in soil carbon modelling related to carbon input calculation method
DEFF Research Database (Denmark)
Keel, Sonja; Leifeld, Jens; Mayer, Jochen
2017-01-01
The application of dynamic models to report changes in soil organic carbon (SOC) stocks, for example as part of greenhouse gas inventories, is becoming increasingly important. Most of these models rely on input data from harvest residues or decaying plant parts and also organic fertilizer, together...... referred to as soil carbon inputs (C). The soil C inputs from plants are derived from measured agricultural yields using allometric equations. Here we compared the results of five previously published equations. Our goal was to test whether the choice of method is critical for modelling soil C and if so......, which of these equations is most suitable for Swiss conditions. For this purpose we used the five equations to calculate soil C inputs based on yield data from a Swiss long-term cropping experiment. Estimated annual soil C inputs from various crops were averaged from 28 years and four fertilizer...
Multiscale methods for gore curvature calculations from FSI modeling of spacecraft parachutes
Takizawa, Kenji; Tezduyar, Tayfun E.; Kolesar, Ryan; Boswell, Cody; Kanai, Taro; Montel, Kenneth
2014-12-01
There are now some sophisticated and powerful methods for computer modeling of parachutes. These methods are capable of addressing some of the most formidable computational challenges encountered in parachute modeling, including fluid-structure interaction (FSI) between the parachute and air flow, design complexities such as those seen in spacecraft parachutes, and operational complexities such as use in clusters and disreefing. One should be able to extract from a reliable full-scale parachute modeling any data or analysis needed. In some cases, however, the parachute engineers may want to perform quickly an extended or repetitive analysis with methods based on simplified models. Some of the data needed by a simplified model can very effectively be extracted from a full-scale computer modeling that serves as a pilot. A good example of such data is the circumferential curvature of a parachute gore, where a gore is the slice of the parachute canopy between two radial reinforcement cables running from the parachute vent to the skirt. We present the multiscale methods we devised for gore curvature calculation from FSI modeling of spacecraft parachutes. The methods include those based on the multiscale sequentially-coupled FSI technique and using NURBS meshes. We show how the methods work for the fully-open and two reefed stages of the Orion spacecraft main and drogue parachutes.
Activity Calculation by Application of Sub-Regular Solution Model in Binary Oxide Systems
Institute of Scientific and Technical Information of China (English)
HOU Yan-qing; XIE Gang; TAO Dong-ping; LI Rong-xing; YU Xiao-hua
2012-01-01
To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been studied. The total average relative errors of component 1 and 2 are 3.2 % and 4.1% respectively by application of the sub-regular solution model into the systems within the whole concentration. However, the total average relative errors are 16 % and 1088 % in the systems presenting saturation concentration. The results show that sub-regular solu- tion model is not good for predicting the systems presenting saturation concentration, especially for the systems con- taining acidic or neutral oxide. The reason may be that the influence of the two types of oxide on the configuration is greater in binary oxide systems. These oxides can be present in the form of complex anion partly, Si-O, Al-O, Ti-O and so on, for example （SiO4）4-. That is contrary to sub-regular solution model which is supposed that the oxide systems consist of cation and O2-. But compared with regular solution model and quasi-regular solution model, sub- regular solution model is closer to the characteristics of actual solution and the calculated results are superior.
A compressible near-wall turbulence model for boundary layer calculations
So, R. M. C.; Zhang, H. S.; Lai, Y. G.
1992-01-01
A compressible near-wall two-equation model is derived by relaxing the assumption of dynamical field similarity between compressible and incompressible flows. This requires justifications for extending the incompressible models to compressible flows and the formulation of the turbulent kinetic energy equation in a form similar to its incompressible counterpart. As a result, the compressible dissipation function has to be split into a solenoidal part, which is not sensitive to changes of compressibility indicators, and a dilational part, which is directly affected by these changes. This approach isolates terms with explicit dependence on compressibility so that they can be modeled accordingly. An equation that governs the transport of the solenoidal dissipation rate with additional terms that are explicitly dependent on the compressibility effects is derived similarly. A model with an explicit dependence on the turbulent Mach number is proposed for the dilational dissipation rate. Thus formulated, all near-wall incompressible flow models could be expressed in terms of the solenoidal dissipation rate and straight-forwardly extended to compressible flows. Therefore, the incompressible equations are recovered correctly in the limit of constant density. The two-equation model and the assumption of constant turbulent Prandtl number are used to calculate compressible boundary layers on a flat plate with different wall thermal boundary conditions and free-stream Mach numbers. The calculated results, including the near-wall distributions of turbulence statistics and their limiting behavior, are in good agreement with measurements. In particular, the near-wall asymptotic properties are found to be consistent with incompressible behavior; thus suggesting that turbulent flows in the viscous sublayer are not much affected by compressibility effects.