Measurement and Calculation Methods of a Stem Image Information
Institute of Scientific and Technical Information of China (English)
Yang Hua; Meng Xianyu; Liu Yan; Cheng Jun
2006-01-01
The paper shows a study on 2-D stem image information collected by a digital camera.Information on a single stem is obtained through calculations after the application of the direct linear transformation model of close-range photogrammetry and binocular stereo vision technology,so that the calculating problem between stem image information and its 2-D coordinate can be solved.Furthermore,the 2-D processing methodology for measuring tree image information simplifies calculating equations and increases calculating speed.Although computer stereo vision techniques for collecting parameters of a single stem shape are comparative,complicated,and expensive,research indicates the efficiently and feasibility of closerange photogrammetry for stem image information.
Methods for calculating phase angle from measured whole body bioimpedance modulus
Nordbotten, Bernt J.; Martinsen, Ørjan G.; Grimnes, Sverre
2010-04-01
Assuming the Cole equation we have developed a method to calculate the Cole parameters (R0, R∞, α, τZ) and the phase angle from four frequency measurements of impedance modulus values. The values obtained compare well with impedance measurements obtained using the Solatron 1294/1260 as obtained when making whole body measurements on five persons. We have also performed calculations using an algorithm based on the Kramers-Kronig approach. The results which are presented show that it is possible to obtain complete body impedance data combining relatively simple measurements with advanced calculation using a laptop. This extends the potential of portable equipment, since the measurements will require less instrumentation.
International Nuclear Information System (INIS)
This paper calculates quantum-mechanically the photoelectron energy spectra excited by attosecond x-rays in the presence of a few-cycle laser. A photoelectron laser phase determination method is used for precise measurements of the pulse natural properties of x-ray intensity and the instantaneous frequency profiles. As a direct procedure without any previous pulse profile assumptions and time-resolved measurements as well as data fitting analysis, this method can be used to improve the time resolutions of attosecond timing and measurements with metrological precision. The measurement range is half of a laser optical cycle
Analytical methods for calculating Continuous Symmetry Measures and the Chirality Measure.
Pinsky, Mark; Dryzun, Chaim; Casanova, David; Alemany, Pere; Avnir, David
2008-12-01
We provide analytical solutions of the Continuous Symmetry Measure (CSM) equation for several symmetry point-groups, and for the associated Continuous Chirality Measure (CCM), which are quantitative estimates of the degree of a symmetry-point group or chirality in a structure, respectively. We do it by solving analytically the problem of finding the minimal distance between the original structure and the result obtained by operating on it all of the operations of a specific G symmetry point group. Specifically, we provide solutions for the symmetry measures of all of the improper rotations point group symmetries, S(n), including the mirror (S(1), C(S)), inversion (S(2), C(i)) as well as the higher S(n)s (n > 2 is even) point group symmetries, for the rotational C(2) point group symmetry, for the higher rotational C(n) symmetries (n > 2), and finally for the C(nh) symmetry point group. The chirality measure is the minimal of all S(n) measures. PMID:18484634
Measurement and calculation of evaporation
Plesničar, Leja
2015-01-01
The thesis presents three selected methods of measurement and calculation of the evapotranspiration on research plot at Hajdrihova 28 in Ljubljana. First method is measurement by evaporation pan type A and the other two methods are empirical equations for potential evapotranspiration calculation: FAO Penman-Monteith equation and Thornthwait equation. The results obtained for all three methods are compared with each other. Calculated results according to the FAO Penman-Monteith equation wer...
International Nuclear Information System (INIS)
We adapted or used on ES EhVM, operating under the control of OS ES, the currently most common algorithms for calculating neutron spectra from measured reaction rates. These programs, together with the neutron cross-section and spectrum libraries, are part of the computerized information system SAIPS. The present article descibes the basic mathematical concepts used in the algorithms of the SAIPS calculation programs
Bianco, Federica B; Oh, Seung Man; Fierroz, David; Liu, Yuqian; Kewley, Lisa; Graur, Or
2015-01-01
We present the open-source Python code pyMCZ that determines oxygen abundance and its distribution from strong emission lines in the standard metallicity scales, based on the original IDL code of Kewley & Dopita (2002) with updates from Kewley & Ellison (2008), and expanded to include more recently developed scales. The standard strong-line diagnostics have been used to estimate the oxygen abundance in the interstellar medium through various emission line ratios in many areas of astrophysics, including galaxy evolution and supernova host galaxy studies. We introduce a Python implementation of these methods that, through Monte Carlo (MC) sampling, better characterizes the statistical reddening-corrected oxygen abundance confidence region. Given line flux measurements and their uncertainties, our code produces synthetic distributions for the oxygen abundance in up to 13 metallicity scales simultaneously, as well as for E(B-V), and estimates their median values and their 66% confidence regions. In additi...
Bianco, F. B.; Modjaz, M.; Oh, S. M.; Fierroz, D.; Liu, Y. Q.; Kewley, L.; Graur, O.
2016-07-01
We present the open-source Python code pyMCZ that determines oxygen abundance and its distribution from strong emission lines in the standard metallicity calibrators, based on the original IDL code of Kewley and Dopita (2002) with updates from Kewley and Ellison (2008), and expanded to include more recently developed calibrators. The standard strong-line diagnostics have been used to estimate the oxygen abundance in the interstellar medium through various emission line ratios (referred to as indicators) in many areas of astrophysics, including galaxy evolution and supernova host galaxy studies. We introduce a Python implementation of these methods that, through Monte Carlo sampling, better characterizes the statistical oxygen abundance confidence region including the effect due to the propagation of observational uncertainties. These uncertainties are likely to dominate the error budget in the case of distant galaxies, hosts of cosmic explosions. Given line flux measurements and their uncertainties, our code produces synthetic distributions for the oxygen abundance in up to 15 metallicity calibrators simultaneously, as well as for E(B- V) , and estimates their median values and their 68% confidence regions. We provide the option of outputting the full Monte Carlo distributions, and their Kernel Density estimates. We test our code on emission line measurements from a sample of nearby supernova host galaxies (z https://github.com/nyusngroup/pyMCZ.
Eason, Thomas J.; Bond, Leonard J.; Lozev, Mark G.
2016-02-01
The accuracy, precision, and reliability of ultrasonic thickness structural health monitoring systems are discussed in-cluding the influence of systematic and environmental factors. To quantify some of these factors, a compression wave ultrasonic thickness structural health monitoring experiment is conducted on a flat calibration block at ambient temperature with forty four thin-film sol-gel transducers and various time-of-flight thickness calculation methods. As an initial calibration, the voltage response signals from each sensor are used to determine the common material velocity as well as the signal offset unique to each calculation method. Next, the measurement precision of the thickness error of each method is determined with a proposed weighted censored relative maximum likelihood analysis technique incorporating the propagation of asymmetric measurement uncertainty. The results are presented as upper and lower confidence limits analogous to the a90/95 terminology used in industry recognized Probability-of-Detection assessments. Future work is proposed to apply the statistical analysis technique to quantify measurement precision of various thickness calculation methods under different environmental conditions such as high temperature, rough back-wall surface, and system degradation with an intended application to monitor naphthenic acid corrosion in oil refineries.
International Nuclear Information System (INIS)
The MIC program aimed for methematical simulation of experiments on measuring reactor control system absorbing rod efficiency and obtained data processing is described. The method of interference corrections used for calculations permits on the base of known values of single control rod efficiency and their mutual influence to determine the efficiency of the system in a whole. The values of the interference corrections for the MIC program are calculated by means of the PNK heterogeneous program. The program is written in FORTRAN for the BESM-6 computers
DEFF Research Database (Denmark)
Barrera Figueroa, Salvador; Rasmussen, Knud; Jacobsen, Finn
2009-01-01
Typically, numerical calculations of the pressure, free-field, and random-incidence response of a condenser microphone are carried out on the basis of an assumed displacement distribution of the diaphragm of the microphone; the conventional assumption is that the displacement follows a Bessel...
International Nuclear Information System (INIS)
In the field of safety regulation system for nuclear facilities after the permanent shutdown of their operations, a verification method of site release and its specific procedure are important technical issues to be resolved in confirmation of decommissioning completion which is a final stage of decommissioning. On the assumption that decision-making on site release would be made based on measurement results of radioactive concentrations of soils at tens of points, we studied a calculation method of the number of measurement points and a specific procedure of decision-making for site release. We derived an equation to calculate the number of measurement points that gives the minimum expected cost of site release verification in ensuring safety of the public, where we took into account probabilities of decision errors caused by uncertainties included in estimated mean radioactive concentrations, scenarios of decision-making to site release and their occurrence probabilities, and cost of verification for each scenario. We also developed a specific procedure of decision-making for site release based on the way of scenarios of decision-making. In the procedure, when the concentration does not meet the criterion, a method of choosing a reasonable countermeasure from two options is included. One is an option of increasing the number of measurement points to reduce uncertainties included in estimated mean radioactive concentrations, and the other is an option of conducting decontamination to decrease radioactive concentrations and remeasuring radiation. (author)
International Nuclear Information System (INIS)
The predictions of the ARGOSY method of calculation are compared with buckling and reaction rate measurements on graphite lattices containing plutonium enriched oxide cluster fuels. Most of the measurements were obtained on one lattice pitch giving a graphite-to-fuel volume ratio similar to that in the Windscale A.G.R. Apart from a reduction of 10% in the values of the capture and fission resonance integrals (4eV to 10KeV) of all nuclides the method as coded in ARGOSY III uses basic nuclear data. It is shown in this report that the buckling predictions of ARGOSY III at room temperature are in agreement with the experimentally determined values within approximately the experimental error, i.e. equivalent to ±0.5% in reactivity. When systematic errors are removed, however, a linear trend with the fraction of fissions occurring in Pu 239 is evident; the calculated reactivity being (0.6 ± 0.3)% low for zero Pu239 content and (0.6 + 0.3)% high for fuel with 80% of fission occurring in Pu 239. The experimentally determined change of buckling between 20 and 390 deg C is predicted to within the experimental error, i,e. equivalent to ± 0.7 mn/deg C. Reaction rate ratios and radial power distributions at all temperatures are predicted well by ARGOSY III. (author)
Energy Technology Data Exchange (ETDEWEB)
Jacquet, X.; Casoli, P.; Authier, N.; Rousseau, G. [CEA, Centre de Valduc, 21120 Is-sur-Tille (France); Barsu, C. [Pl. de la fontaine, 25410 Corcelles-Ferrieres (France)
2011-07-01
Caliban is a cylindrical metallic core reactor mainly composed of uranium 235. It is operated by the Criticality and Neutron Science Research Laboratory located at the French Atomic Energy Commission research center in Valduc. As with other fast burst reactors, Caliban is used extensively for determining the responses of electronic parts or other objects and materials to neutron-induced displacements. Therefore, Caliban's irradiation characteristics, and especially its central cavity neutron spectrum, have to be very accurately evaluated. The foil activation method has been used in the past by the Criticality and Neutron Science Research Laboratory to evaluate the neutron spectrum of the different facilities it operated, and in particular to characterize the Caliban cavity spectrum. In order to strengthen and to improve our knowledge of the Caliban cavity neutron spectrum and to reduce the uncertainties associated with the available evaluations, new measurements have been performed on the reactor and interpreted by the foil activation method. A sensor set has been selected to sample adequately the studied spectrum. Experimental measured reaction rates have been compared to the results from UMG spectrum unfolding software and to values obtained with the activation code Fispact. Experimental and simulation results are overall in good agreement, although gaps exist for some sensors. UMG software has also been used to rebuild the Caliban cavity neutron spectrum from activation measurements. For this purpose, a default spectrum is needed, and one has been calculated with the Monte-Carlo transport code Tripoli 4 using the benchmarked Caliban description. (authors)
Vreede, F. A.
1981-05-01
The manual of instructions for the user of the CSIR triaxial rock stress measuring equipment is critically examined. It is shown that the values of the rock stresses can be obtained from the strain gauge records by means of explicit formulae, which makes the manual's computer program obsolete. Furthermore statistical methods are proposed to check for faulty data and inhomogeneity in rock properties and virgin stress. The possibility of non-elastic behavior of the rock during the test is also checked. A new computer program based on the explicit functions and including the check calculations is presented. It is much more efficient than the one in the manual since it does not require computer sub-routines, allowing it to be used directly on any modern computer. The output of the new program is in a format suitable for direct inclusion in the report of an investigation using strain cell results.
Treanor, Morag C.
2014-01-01
Poverty can either be measured directly, through standards of living such as material deprivation, or indirectly through resources available, usually income. Research shows that the optimum measure of poverty combines these methods, a fact that the UK government took cognisance of in its tripartite measure of child poverty. For use in a birth cohort study, two methods of calculating material deprivation were tested: the method used by the UK government taken from the Family Resources Survey (...
Energy Technology Data Exchange (ETDEWEB)
Smith, L.A.; Gallmeier, F.X. [Oak Ridge Institute for Science and Energy, TN (United States); Gehin, J.C. [Oak Ridge National Lab., TN (United States)] [and others
1995-05-01
The FOEHN critical experiment was analyzed to validate the use of multigroup cross sections and Oak Ridge National Laboratory neutronics computer codes in the design of the Advanced Neutron Source. The ANSL-V 99-group master cross section library was used for all the calculations. Three different critical configurations were evaluated using the multigroup KENO Monte Carlo transport code, the multigroup DORT discrete ordinates transport code, and the multigroup diffusion theory code VENTURE. The simple configuration consists of only the fuel and control elements with the heavy water reflector. The intermediate configuration includes boron endplates at the upper and lower edges of the fuel element. The complex configuration includes both the boron endplates and components in the reflector. Cross sections were processed using modules from the AMPX system. Both 99-group and 20-group cross sections were created and used in two-dimensional models of the FOEHN experiment. KENO calculations were performed using both 99-group and 20-group cross sections. The DORT and VENTURE calculations were performed using 20-group cross sections. Because the simple and intermediate configurations are azimuthally symmetric, these configurations can be explicitly modeled in R-Z geometry. Since the reflector components cannot be modeled explicitly using the current versions of these codes, three reflector component homogenization schemes were developed and evaluated for the complex configuration. Power density distributions were calculated with KENO using 99-group cross sections and with DORT and VENTURE using 20-group cross sections. The average differences between the measured values and the values calculated with the different computer codes range from 2.45 to 5.74%. The maximum differences between the measured and calculated thermal flux values for the simple and intermediate configurations are {approx} 13%, while the average differences are < 8%.
Calculation method of Tesla coil
Коломієць, Роман Олександрович
2015-01-01
Tesla coil, despite the simplicity of its design may be called one of the least studied electronic devices. The article is an attempt to bring in various experimental results of general theoretical framework, which is the basis of exact calculation method of Tesla coils. Such calculation should be the starting point to create devices based on it. In order to develop such methods were considered the general principles of designing Tesla coil, reviewed the most famous mathematical models of its...
Comparison of methods for calculating water erosion
Svobodová, Pavlína
2011-01-01
Bachelor thesis presents a comparison of methods for calculating water erosion. The aim is to summarize available evidence concerning the problems of water erosion. There are presented some methods how to calculate average annual erosion of soils, and selected models for calculating the erosion immediately. There are also listed possible erosion control measures through which we can at least slow the effects of erosion, rather than stop completely.
Energy Technology Data Exchange (ETDEWEB)
Kulacsy, K.; Lux, I. [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics
1997-03-01
A new, approximate method is given to calculate the in-core flux from the current of SPNDs, with a delay of only a few seconds. The stability of this stepwise algorithm is proven to be satisfactory, and the results of tests performed both on synthetic and on real data are presented. The reconstructed flux is found to follow both steady state and transient fluxes well. (author).
International Nuclear Information System (INIS)
A new, approximate method is given to calculate the in-core flux from the current of SPNDs, with a delay of only a few seconds. The stability of this stepwise algorithm is proven to be satisfactory, and the results of tests performed both on synthetic and on real data are presented. The reconstructed flux is found to follow both steady state and transient fluxes well. (author)
Directory of Open Access Journals (Sweden)
Мaryna O. Golofeyeva
2015-12-01
Full Text Available The effective use of heterogeneous non-metallic materials and structures needs measurement of reliable values of dissipation characteristics, as well as common factors of their change during the loading process. Aim: The aim of this study is to prepare the budget for measurement uncertainty of dissipative properties of composite materials. Materials and Methods: The method used to study the vibrational energy dissipation characteristics based on coupling of vibrations damping decrement and acoustic velocity in a non-metallic heterogeneous material is reviewed. The proposed method allows finding the dependence of damping on vibrations amplitude and frequency of strain-stress state of material. Results: Research of the accuracy of measurement method during the definition of decrement attenuation of fluctuations in synthegran was performed. The international approach for evaluation of measurements quality is used. It includes the common practice international rules for uncertainty expression and their summation. These rules are used as internationally acknowledged confidence measure to the measurement results, which includes testing. The uncertainties budgeting of acoustic method for measurement of dissipative properties of materials were compiled. Conclusions: It was defined that there are two groups of reasons resulting in errors during measurement of materials dissipative properties. The first group of errors contains of parameters changing of calibrated bump in tolerance limits, displacement of sensor in repeated placement to measurement point, layer thickness variation of contact agent because of irregular hold-down of resolvers to control surface, inaccuracy in reading and etc. The second group of errors is linked with density and Poisson’s ratio measurement errors, distance between sensors, time difference between signals of vibroacoustic sensors.
Methods of core neutronic calculation
International Nuclear Information System (INIS)
Core neutronic calculations lead to the determination of geometry, composition, controls systems and to the core exploitation limits in agreement with the expected performances, with safety rules, technological choices and fuel management methods. Neutronic calculations object are described with physics justifications of hypothesis and approximations. A description and a definition of reactivity and power distribution are also given. A panorama of calculation methods used in the conception of fast breeder and pressure water reactors, are described with numerical aspects and general interest considerations related to the field of these methods and to the industrial options chosen. A complete industrial uses panorama of methods derived from the classical or generalized perturbation theory is followed by the qualification and the definition of the validity field of numerical codes.(A.B.). 88 refs., 6 figs
Friction and wear calculation methods
Kragelsky, I V; Kombalov, V S
1981-01-01
Friction and Wear: Calculation Methods provides an introduction to the main theories of a new branch of mechanics known as """"contact interaction of solids in relative motion."""" This branch is closely bound up with other sciences, especially physics and chemistry. The book analyzes the nature of friction and wear, and some theoretical relationships that link the characteristics of the processes and the properties of the contacting bodies essential for practical application of the theories in calculating friction forces and wear values. The effect of the environment on friction and wear is a
International Nuclear Information System (INIS)
Extensive neutron and gamma attenuation measurements have been performed in magnetite and ordinary concrete up to a depth of 2 metres in order to study the accuracy attainable by some shield calculation methods. The effect of thin, heavy layers (Pb) has also been studied. Experimental facilities and instrumentation, especially the foil detection methods used for thermal and epithermal neutrons, are described in some detail. Great weight is laid upon a thorough error analysis. The fluxes measured are compared to those calculated by an earlier version of the British 18-group removal method (RASH B3), by an improved removal method (NRN) developed at AB Atomenergi, and by numerical integration of the Boltzmann equation (NIOBE). The results show that shielding calculations with the newer methods give fluxes that are generally within a factor of 2-3 from the true values. A greater accuracy seems to be difficult to obtain in practice in spite of possible improvements in the mathematical solution of the transport problem. The greatest errors originate in the translation between the true and calculation geometries in the uncertainty of material properties in the case of concrete, and in approximations and inaccuracies of radiation sources
Jones, Thomas; Laughlin, Thomas
2009-01-01
Nothing could be more effective than a wilderness experience to demonstrate the importance of conserving biodiversity. When that is not possible, though, there are computer models with several features that are helpful in understanding how biodiversity is measured. These models are easily used when natural resources, transportation, and time…
超声波流量测量中流速计算方法的对比%Comparison of flow rate calculation method for ultrasonic flow measurement
Institute of Scientific and Technical Information of China (English)
于洋; 宗光华; 丁凤林
2013-01-01
超声波流量计(UFM,Ultrasonic Flow Meter)通过测量管路中顺流和逆流方向的超声波传播时间变化计算流速,因此超声波传播时间的准确测量对流量计的精度影响至关重要.对超声波流量计的测量方法进行研究,从环境温度的变化、时间测量的准确性、不确定度的计算3个方面,对比超声波传播时间差法和频率差法对流量测量精度的影响.通过超声波流量测量实验,验证了在流量计未校准的情况下,与频率差法相比,时间差法的测量精度更高,且其校准系数曲线的线性度更好,校准后可在全流量范围内获得更高的测量精度.%Ultrasonic flow meter ( UFM ) calculates the flow rate, by measuring the difference of ultrasound transit time between the upstream direction and downstream direction. For the purpose of accurate flow measurement, transit time difference method and frequency difference method were compared from three aspects; change of environment temperature, accuracy of time measurement, and uncertainty calculation. Ultrasonic flow measurement experiment shows, when the flow meter is not calibrated, compared with frequency difference method, transit time difference method can achieve better accuracy. The calibrated factor for the transit time difference method is more linear, so better accuracy is achieved for full flow range measurement.
Kurhan, D. N.; Lapsheva, N. M.
2013-01-01
One of the ways to increase safety and operation of seamless path is the determination of the stress-strain state rail lashes that enables you to warn and prevent failures continuous welded rail. It is known that significant longitudinal force are caused by limitations of the temperature regime of continuous welded rail and can lead to the release. For long-term development and improvement of the theory of thermal stress state of continuous welded rail have created several different methods f...
International Nuclear Information System (INIS)
This thesis presents the radiative corrections to the virtual compton scattering and the magnetic method adopted in the Hall A at Jefferson Laboratory, to measure the electrons beam energy with an accuracy of 104. The virtual compton scattering experiments allow the access to the generalised polarizabilities of the protons. The extraction of these polarizabilities is obtained by the experimental and theoretical cross sections comparison. That's why the systematic errors and the radiative effects of the experiments have to be controlled very seriously. In this scope, a whole calculation of the internal radiative corrections has been realised in the framework of the quantum electrodynamic. The method of the dimensional regularisation has been used to the treatment of the ultraviolet and infra-red divergences. The absolute measure method of the energy, takes into account the magnetic deviation, made up of eight identical dipoles. The energy is determined from the deviation angle calculation of the beam and the measure of the magnetic field integral along the deviation
Calculation Methods for Wallenius’ Noncentral Hypergeometric Distribution
DEFF Research Database (Denmark)
Fog, Agner
2008-01-01
conditional distribution of independent binomial variates given their sum. No reliable calculation method for Wallenius' noncentral hypergeometric distribution has hitherto been described in the literature. Several new methods for calculating probabilities from Wallenius' noncentral hypergeometric...
ANALYTICAL METHODS FOR CALCULATING FAN AERODYNAMICS
Directory of Open Access Journals (Sweden)
Jan Dostal
2015-12-01
Full Text Available This paper presents results obtained between 2010 and 2014 in the field of fan aerodynamics at the Department of Composite Technology at the VZLÚ aerospace research and experimental institute in Prague – Letnany. The need for rapid and accurate methods for the preliminary design of blade machinery led to the creation of a mathematical model based on the basic laws of turbomachine aerodynamics. The mathematical model, the derivation of which is briefly described below, has been encoded in a computer programme, which enables the theoretical characteristics of a fan of the designed geometry to be determined rapidly. The validity of the mathematical model is assessed continuously by measuring model fans in the measuring unit, which was developed and manufactured specifically for this purpose. The paper also presents a comparison between measured characteristics and characteristics determined by the mathematical model as the basis for a discussion on possible causes of measured deviations and calculation deviations.
Methods in nuclear reactors calculations
International Nuclear Information System (INIS)
Studies are made of the neutron transport equation corresponding to the the real and virtual reactors, as well as the starting hypotheses. Methods are developed to solve the transport equation in slab geometry, and Pl; Bl; Ml; Sn and discrete ordinates approximations. (Author)
American Society for Testing and Materials. Philadelphia
2005-01-01
1.1 This test method covers the calculation from heat transfer theory of the stagnation enthalpy from experimental measurements of the stagnation-point heat transfer and stagnation pressure. 1.2 Advantages 1.2.1 A value of stagnation enthalpy can be obtained at the location in the stream where the model is tested. This value gives a consistent set of data, along with heat transfer and stagnation pressure, for ablation computations. 1.2.2 This computation of stagnation enthalpy does not require the measurement of any arc heater parameters. 1.3 Limitations and ConsiderationsThere are many factors that may contribute to an error using this type of approach to calculate stagnation enthalpy, including: 1.3.1 TurbulenceThe turbulence generated by adding energy to the stream may cause deviation from the laminar equilibrium heat transfer theory. 1.3.2 Equilibrium, Nonequilibrium, or Frozen State of GasThe reaction rates and expansions may be such that the gas is far from thermodynamic equilibrium. 1.3.3 Noncat...
International Nuclear Information System (INIS)
Accurate and transparent measurement and monitoring of radiologist workload is highly desirable for management of daily workflow in a radiology department, and for informing decisions on department staffing needs. It offers the potential for benchmarking between departments and assessing future national workforce and training requirements. We describe a technique for quantifying, with minimum subjectivity, all the work carried out by radiologists in a tertiary department. Six broad categories of clinical activities contributing to radiologist workload were identified: reporting, procedures, trainee supervision, clinical conferences and teaching, informal case discussions, and administration related to referral forms. Time required for reporting was measured using data from the radiology information system. Other activities were measured by observation and timing by observers, and based on these results and extensive consultation, the time requirements and frequency of each activity was agreed on. An activity list was created to record this information and to calculate the total clinical hours required to meet the demand for radiologist services. Diagnostic reporting accounted for approximately 35% of radiologist clinical time; procedures, 23%; trainee supervision, 15%; conferences and tutorials, 14%; informal case discussions, 10%; and referral-related administration, 3%. The derived data have been proven reliable for workload planning over the past 3 years. A transparent and robust method of measuring radiologists' workload has been developed, with subjective assessments kept to a minimum. The technique has value for daily workload and longer term planning. It could be adapted for widespread use.
Pile Load Capacity – Calculation Methods
Directory of Open Access Journals (Sweden)
Wrana Bogumił
2015-12-01
Full Text Available The article is a review of the current problems of the foundation pile capacity calculations. The article considers the main principles of pile capacity calculations presented in Eurocode 7 and other methods with adequate explanations. Two main methods are presented: α – method used to calculate the short-term load capacity of piles in cohesive soils and β – method used to calculate the long-term load capacity of piles in both cohesive and cohesionless soils. Moreover, methods based on cone CPTu result are presented as well as the pile capacity problem based on static tests.
Approximate methods in gamma-ray skyshine calculations
International Nuclear Information System (INIS)
An approximate computational method for gamma-ray skyshine calculations is described. The method is suitable for a source collimated uniformly about the vertical and accounts for uniform overhead concrete shielding above the source. Results of calculations are compared to measurements as well as results of other calculations
Measuring method and calculation of the evaporation rate for LNG storage tank%LNG储罐日蒸发率测量方法及计算
Institute of Scientific and Technical Information of China (English)
李晓明; 许燕; 姚淑婷; 王冰; 李国艳
2013-01-01
The evaporation rate is an important index of the insulation performance for LNG storage tank,and it is beneficial to better understand the evaporation rote for safe operation for LNG storage tank.Combined with the definition and standard of the evaporation rate of storage tank,and based on the actual operation situations,several measuring methods and calculation formulas of the evaporation rate for LNG storage tank were given in this paper,and the applicability and technological conditions of different measuring methods were also discussed.%日蒸发率是衡量LNG储罐绝热性能的重要指标,有效了解储罐日蒸发率,将有利于LNG储罐安全运行的维护.结合储罐日蒸发率的定义和标准,根据实际操作情况,给出了几种测量LNG储罐日蒸发率的方法及其计算公式,并论述了各种测量方法的适用性和工艺条件.
International Nuclear Information System (INIS)
A calculation for double scattering and absorption corrections in fast neutron scattering experiments using Monte-Carlo method is given. Application to cylindrical target is presented in FORTRAN symbolic language. (author)
Glass dissolution rate measurement and calculation revisited
Fournier, Maxime; Ull, Aurélien; Nicoleau, Elodie; Inagaki, Yaohiro; Odorico, Michaël; Frugier, Pierre; Gin, Stéphane
2016-08-01
Aqueous dissolution rate measurements of nuclear glasses are a key step in the long-term behavior study of such waste forms. These rates are routinely normalized to the glass surface area in contact with solution, and experiments are very often carried out using crushed materials. Various methods have been implemented to determine the surface area of such glass powders, leading to differing values, with the notion of the reactive surface area of crushed glass remaining vague. In this study, around forty initial dissolution rate measurements were conducted following static and flow rate (SPFT, MCFT) measurement protocols at 90 °C, pH 10. The international reference glass (ISG), in the forms of powders with different particle sizes and polished monoliths, and soda-lime glass beads were examined. Although crushed glass grains clearly cannot be assimilated with spheres, it is when using the samples geometric surface (Sgeo) that the rates measured on powders are closest to those found for monoliths. Overestimation of the reactive surface when using the BET model (SBET) may be due to small physical features at the atomic scale-contributing to BET surface area but not to AFM surface area. Such features are very small compared with the thickness of water ingress in glass (a few hundred nanometers) and should not be considered in rate calculations. With a SBET/Sgeo ratio of 2.5 ± 0.2 for ISG powders, it is shown here that rates measured on powders and normalized to Sgeo should be divided by 1.3 and rates normalized to SBET should be multiplied by 1.9 in order to be compared with rates measured on a monolith. The use of glass beads indicates that the geometric surface gives a good estimation of glass reactive surface if sample geometry can be precisely described. Although data clearly shows the repeatability of measurements, results must be given with a high uncertainty of approximately ±25%.
Thermal Bridges in Building Construction - Measurements and Calculations
DEFF Research Database (Denmark)
Rose, Jørgen
The thesis investigates detailed calculation methods for evaluating heat loss through building envelope constructions, or more specific, thermal bridges. First a detailed description of the calculation methods, i.e. both calculation programs and guidelines, for calculating typical thermal bridges...... detailed calculations in more operational and applicable projecting tools, e.g. thermal bridge catalogues or U-value tables....... in building envelope constructions is given. After this a validation of both programs and guidelines is presented. The validation is performed by comparing calculated U-values with Guarded Hot Box measurements. The last part of the thesis discusses the possibilities of utilising the results of...
Assessment of seismic margin calculation methods
Energy Technology Data Exchange (ETDEWEB)
Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.
1989-03-01
Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs.
Assessment of seismic margin calculation methods
International Nuclear Information System (INIS)
Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs
Estrada, J
1994-01-01
Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of sup 2 sup 1 sup 0 Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measureme...
International Nuclear Information System (INIS)
The aim of this work is to elaborate a Monte Carlo programme which calculate the photoelectric efficiency of a planar high purity Ge detector for low energy photons. This programme calculate the auto absorption, the absorption in different media crossed by the photon and the intrinsic and total efficiencies. The results of this programme were very satisfactory since they reproduce the measured values in the two different cases of punctual and volumic sources. The result of the photoelectric efficiency calculation with this programme has been applied to determine the cross section of the 166-Er (n,2 n) 165-Er reaction induced by 14 MeV neutron, where only the measurement by x spectrometry is possible. The value obtained is concordant with the data given by the literature. 119 figs., 39 tabs., 96 refs. (F.M.)
A novel algorithmic method for piezoresistance calculation
International Nuclear Information System (INIS)
A novel algorithmic method, based on the different stress distribution on the surface of thin film in an SOI microstructure, is put forward to calculate the value of the silicon piezoresistance on the sensitive film. In the proposed method, we take the Ritz method as an initial theoretical model to calculate the rate of piezoresistance ΔR/R through an integral (the closed area Ω where the surface piezoresistance of the film lies as the integral area and the product of stress σ and piezoresistive coefficient π as the integral object) and compare the theoretical values with the experimental results. Compared with the traditional method, this novel calculation method is more accurate when applied to calculating the value of the silicon piezoresistance on the sensitive film of an SOI pieoresistive pressure sensor. (semiconductor devices)
Reliability importance measures and their calculation
International Nuclear Information System (INIS)
The importance of a component to the system reliability or availability and to the system failure rate can be measured by a number of importance measures. Such measures can be used to guide the system design improvement actions as well as the diagnostic and repair actions. This report develops relationships between several importance measures, illustrates their meaning with interpretations and applications, and describes the computer program called IMPO that calculates importance measures when the system minimum cat sets and component parameters are given. A user's manual is included with illustrative examples
International Nuclear Information System (INIS)
Method for determination f residual welding stresses making it possible to reduce uncertainty in calculational conditions for heat exchange of welding details with the environment and equipment through application of shell wall actual temperatures, changing in the course of welding, is proposed.Tubes of 12Kh18N10T steel were chosen for the method experimental verification. 5 refs., 5 figs., 1 tab
Methods of bone marrow dose calculation
International Nuclear Information System (INIS)
Several methods of bone marrow dose calculation for photon irradiation were analised. After a critical analysis, the author proposes the adoption, by the Instituto de Radioprotecao e Dosimetria/CNEN, of Rosenstein's method for dose calculations in Radiodiagnostic examinations and Kramer's method in case of occupational irradiation. It was verified by Eckerman and Simpson that for monoenergetic gamma emitters uniformly distributed within the bone mineral of the skeleton the dose in the bone surface can be several times higher than dose in skeleton. In this way, is also proposed the Calculation of tissue-air ratios for bone surfaces in some irradiation geometries and photon energies to be included in the Rosenstein's method for organ dose calculation in Radiodiagnostic examinations. (Author)
Relaxation Method For Calculating Quantum Entanglement
Tucci, R R
2001-01-01
In a previous paper, we showed how entanglement of formation can be defined as a minimum of the quantum conditional mutual information (a.k.a. quantum conditional information transmission). In classical information theory, the Arimoto-Blahut method is one of the preferred methods for calculating extrema of mutual information. We present a new method akin to the Arimoto-Blahut method for calculating entanglement of formation. We also present several examples computed with a computer program called Causa Comun that implements the ideas of this paper.
Calculation and measurement of horizontal flow fields in tidal rivers
International Nuclear Information System (INIS)
A new technique for horizontal flow measurements in tidal rivers by the moving boat method is described. A two-dimensional tidal model for shallow waters using measured velocity cross-profiles on the open boundaries is developed. The flow field of the lower Weser river is calculated and comparisons of numerical results with measured field data are performed. The influence of model parameters on the calculated flow fields is discussed. (orig.)
International Nuclear Information System (INIS)
Continuous-wave near-infrared spectroscopy and imaging enable tissue hemodynamics and oxygenation to be determined non-invasively. Movements of the investigated subject can cause movement artifacts (MAs) in the recorded signals. The strength and type of MAs induced depend on the measurement principle. The aim of the present study was to investigate the quantitative relationship between different single-distance (SD) and multi-distance (MD) measurement methods and their susceptibility to MAs. We found that each method induces MAs to a different degree, and that MD methods are more robust against MAs than SD methods. (paper)
International Nuclear Information System (INIS)
Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of 210 Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m3 to 150.000 Bq/m3 were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses estimated, for the same
Reactor perturbation calculations by Monte Carlo methods
International Nuclear Information System (INIS)
Whilst Monte Carlo methods are useful for reactor calculations involving complicated geometry, it is difficult to apply them to the calculation of perturbation worths because of the large amount of computing time needed to obtain good accuracy. Various ways of overcoming these difficulties are investigated in this report, with the problem of estimating absorbing control rod worths particularly in mind. As a basis for discussion a method of carrying out multigroup reactor calculations by Monte Carlo methods is described. Two methods of estimating a perturbation worth directly, without differencing two quantities of like magnitude, are examined closely but are passed over in favour of a third method based on a correlation technique. This correlation method is described, and demonstrated by a limited range of calculations for absorbing control rods in a fast reactor. In these calculations control rod worths of between 1% and 7% in reactivity are estimated to an accuracy better than 10% (3 standard errors) in about one hour's computing time on the English Electric KDF.9 digital computer. (author)
Willow growing - Methods of calculation and profitability
International Nuclear Information System (INIS)
The calculation method presented here makes it possible to conduct profitability comparisons between annual and perennial crops and in addition take the planning situation into account. The method applied is a modified total step calculation. The difference between a traditional total step calculation and the modified version is the way in which payments and disbursements are taken into account over a period of several years. This is achieved by combining the present value method and the annuity method. The choice of interest rate has great bearing on the result in perennial calculations. The various components influencing the interest rate are analysed and factors relating to the establishment of the interest rate in different situations are described. The risk factor can be an important variable component of the interest rate calculation. Risk is also addressed from an approach in accordance with portfolio theory. The application of the methods sheds light on the profitability of Salix cultivation from the viewpoint of business economics, and also how different factors influence the profitability of Salix cultivation. Aspects studied are harvesting intervals, the importance of yield level, the competitiveness of Salix versus grain cultivation, the influence of income taxes on profitability etc. Methods for evaluation of activities concerning cultivation of a perennial crop are described and also involve the application of nitrogen fertilization to Salix cultivation. Studies have been performed using these methods to look into nitrogen fertilizer profitability in Salix cultivation during the first rotation period. Nitrogen fertilizer profitability has been investigated involving both production functions and cost calculations, taking the year fertilization into consideration. 72 refs., 2 figs., 52 tabs
DNBR limit calculation by sampling statistical method
International Nuclear Information System (INIS)
The parametric uncertainties of DNBR and exit quality were calculated using sampling statistical method based on Wilks formula and VIPRE-W code. Then the DNBR design limit and exit quality limit were got by combining with the uncertainties of models and DNB correlation. This method can gain the more DNBR margin than RTDP methodology which is developed by Westinghouse by comparison of these two methods. (authors)
Comparison between measured and calculated neutron spectra in FCA assemblies
International Nuclear Information System (INIS)
The neutron spectra measured in FCA Assembly VI-2, VI-1 and V-2 are discussed, and are compared with the results by calculation. The data were obtained by measurements of proton-recoil counter and double scintillator methods. Calculations were made with cell-program SP-2000 and fine-group cross section library AGRI/2, and the spectra with 1950 groups and broadened 64 and 26 group were derived. The measured spectra in the energy range of 5 keV to 6 MeV were effectively compared with the calculational results, by using C/E values. There are large differences between the measured and the calculated spectra near the 430 keV oxygen and 29 keV iron resonances. The experimental and the calculated central fission rate ratios were also compared. (author)
A method for tokamak neutronics calculations
International Nuclear Information System (INIS)
This paper presents a new method for neutron transport calculation in tokamak fusion reactors. The computational procedure is based on the solution of the even-parity transport equation in a toroidal geometry. The angular neutron distribution is treated by even-parity spherical harmonic expansion, while the spatial dependence is approximated by using R-function finite elements that are defined for regions of arbitrary geometric shape. In order to test the method, calculation of a simplified tokamak model is carried out. The results are compared with the results from the literature and for the same order of accuracy a reduction of the number of spatial unknowns is shown. (author)
Calculation of skid resistance from texture measurements
Directory of Open Access Journals (Sweden)
Andreas Ueckermann
2015-02-01
Full Text Available There is a wide range of routine skid resistance measurement devices on the market. All of them are measuring the friction force between a rubber wheel and the wetted road surface. Common to all of them is that they are relatively complex and costly because generally a truck carrying a large water tank is needed to wet the surface with a defined water layer. Because of the limited amount of water they can carry they are limited in range. Besides that the measurement is depending on factors like water film thickness, temperature, measurement speed, rubber aging, rubber wear and even road evenness and curviness. All of these factors will affect the skid resistance and are difficult to control. We present a concept of contactless skid resistance measurement which is based on optical texture measurement and consists of two components: measurement of the pavement texture by means of an optical measuring system and calculation of the skid resistance based on the measured texture by means of a rubber friction model. The basic assumptions underlying the theoretical approach and the model itself based on the theory of Persson are presented. The concept is applied to a laboratory device called Wehner/Schulze (W/S machine to prove the theoretical approach. The results are very promising. A strong indication could be provided that skid resistance could be measured without contact in the future.
Multigrid Methods in Electronic Structure Calculations
Briggs, E L; Bernholc, J
1996-01-01
We describe a set of techniques for performing large scale ab initio calculations using multigrid accelerations and a real-space grid as a basis. The multigrid methods provide effective convergence acceleration and preconditioning on all length scales, thereby permitting efficient calculations for ill-conditioned systems with long length scales or high energy cut-offs. We discuss specific implementations of multigrid and real-space algorithms for electronic structure calculations, including an efficient multigrid-accelerated solver for Kohn-Sham equations, compact yet accurate discretization schemes for the Kohn-Sham and Poisson equations, optimized pseudo\\-potentials for real-space calculations, efficacious computation of ionic forces, and a complex-wavefunction implementation for arbitrary sampling of the Brillioun zone. A particular strength of a real-space multigrid approach is its ready adaptability to massively parallel computer architectures, and we present an implementation for the Cray-T3D with essen...
Measurements and calculations for nuclear emergency management
International Nuclear Information System (INIS)
Within the regime of operational emergency management, the ''monitoring'' activities are closely linked with the ''action plan''. A large part of the tasks defined there is determined on the basis of measured values referring to contamination levels or radiation doses, so that measurement or calculation of radiation exposure and resulting doses is a high-priority task. The measured values are vital information required for decisions for appropriate action. The contributions to this publication give a survey of the present system of monitoring tasks to be carried out in the event of a nuclear emergency, ranging from measurement through to dose reconstruction. The information given refers to scenarios established for nuclear installations or conditions in Germany, Austria and Switzerland. (orig./CB)
A New Iterative Method to Calculate [pi
Dion, Peter; Ho, Anthony
2012-01-01
For at least 2000 years people have been trying to calculate the value of [pi], the ratio of the circumference to the diameter of a circle. People know that [pi] is an irrational number; its decimal representation goes on forever. Early methods were geometric, involving the use of inscribed and circumscribed polygons of a circle. However, real…
Covariant method for calculating helicity amplitudes
International Nuclear Information System (INIS)
We present an alternative approach for calculating helicity amplitudes for processes involving both massless and massive fermions. With this method one can easily obtain covariant expressions for the helicity amplitudes. The final expressions involve only four-vector products and are independent of the basis for γ matrices or specific form of the spinors. We use the method to obtain the helicity amplitudes for several processes involving top quark production. copyright 1996 The American Physical Society
Measured and calculated NO2 concentrations in Amsterdam in 2008
International Nuclear Information System (INIS)
Calculations using the Dutch standard calculation method for air quality in urban streets performed for 38 streets in Amsterdam in 2008 yield, on average, lower Nitrogen dioxide concentrations than measurements at those locations. This follows from research by the RIVM and the Public Health Service of Amsterdam (GGD Amsterdam). The average difference between measured and calculated concentrations is 11 %. At measuring locations of the National Air Quality Measuring Network in the Netherlands no significant underestimation of concentrations by the model is observed. The research was performed by the Dutch ministry of Housing, Spatial Planning en the Environment (VROM). The air quality in the streets that were investigated is mainly determined by emissions from local traffic. The measurements have been performed during thirteen periods of four weeks each, using so called 'Palmes' diffusion tubes. These measurements have been calibrated using the European reference method that is operational in the permanent measuring stations of the GGD Amsterdam. The calculations were performed using the geometry of the roads and information of the traffic at the measuring locations. Part of the differences can be explained, as some locations are not within the scope of the model. In these situations the model is known to perform slightly less. Apart from local traffic, other sources, like shipping, also contribute to the NO2 background concentrations in streets in Amsterdam. Sources that have only globally been included in the calculation of this background concentration may influence concentrations at specific locations. Further studies on this subject will be conducted in 2010.
Cloud droplet measurement methods
International Nuclear Information System (INIS)
All important techniques to measure cloud and fog droplets are mentioned in this compendium. It especially refers to those authors who established and developed measurement methods for cloud droplets and to those whose papers contained cloud droplet size distributions. (orig.)
Wang, Houmao; Wang, Yongmei
2015-11-01
A ground-based Fabry-Perot interferometer (FPI) fabricated by American National Center for Atmospheric Research (A-NCAR) was deployed in Kelan (111.6° E, 38.7° N), in middle of China, to observe OH 892.0 nm, OI 630.0 nm, and OI 557.7 nm airglow emissions for wind retrieval of mesospheric and thermospheric atmosphere using a method based on the convolution of the source profile and instrumental function. Based on the instrument, wind velocities were retrieved using another retrieval method but improved in both noise reduction and choice of interference fringes, which can reduce the disturbance of bad fringes and advance the retrieval precision. The retrieval results were subsequently compared with the FPI wind products, and good agreement was found between them. The averaged deviations of wind velocities between the two retrieval methods depend on airglow intensity with 5.7 m/s for 892.0 nm emission, 6.18 m/s for 630.0 nm emission, and 3.66 m/s for 557.7 nm emission, respectively. Then, a new method was proposed for error calculation by considering the influence of airglow intensity, CCD dark noise, background emissions, and data processing, which can steadily evaluate the precision and reliability of wind retrieval. The relationships between errors derived from the two retrieval methods and airglow intensity were compared and analyzed. It is found that the variation of errors is inversely correlated with the variation of airglow intensity.
Hemielectron method generalization for complex compound calculations
International Nuclear Information System (INIS)
A hemielectron method is considered as applied to the systems having one open shell (n electrons on m-fold degenerated level) or several open shells. General expressions for corrections to a total energy of the system and to energies of monoelectron levels, corresponding to an unfilled shell, are obtained. Using the [RuCl6]3- complex as an example, expendiency of the approach application to the calculation of electron structure of coordination compounds is shown
Energy Technology Data Exchange (ETDEWEB)
Henniger, Juergen; Jakobi, Christoph [Technische Univ. Dresden (Germany). Arbeitsgruppe Strahlungsphysik (ASP)
2015-07-01
From a mathematical point of view Monte Carlo methods are the numerical solution of certain integrals and integral equations using a random experiment. There are several advantages compared to the classical stepwise integration. The time required for computing increases for multi-dimensional problems only moderately with increasing dimension. The only requirements for the integral kernel are its capability of being integrated in the considered integration area and the possibility of an algorithmic representation. These are the important properties of Monte Carlo methods that allow the application in every scientific area. Besides that Monte Carlo algorithms are often more intuitive than conventional numerical integration methods. The contribution demonstrates these facts using the example of dead time corrections for counting measurements.
DEFF Research Database (Denmark)
Diamond, J. M.
1965-01-01
A noise-measuring method based on the use of a calibrated noise generator and an output meter with a special scale is described. The method eliminates the effect of noise contributions occurring in the circuits following the device under test.......A noise-measuring method based on the use of a calibrated noise generator and an output meter with a special scale is described. The method eliminates the effect of noise contributions occurring in the circuits following the device under test....
Nodal expansion method for reactor core calculations
International Nuclear Information System (INIS)
To perform realistic space dependent reactor dynamics analyses in large power reactor with all asymmetric material, control and shutdown devices, a full three dimensional calculation model is essential. A code FEMINA (Flux Expansion Method In Nodal Analysis) implementing a higher order nodal scheme employing a nodal flux expansion method in 3D is being developed. In this report the first part of this code viz., the theory of the static version and its validation with well known benchmark problems are described. The code has been found to be quite accurate as well as fast. It is available on DEC 10'', CYBER 170/730 and ND 540 computers. (author)
Acceleration methods and models in Sn calculations
International Nuclear Information System (INIS)
In some neutron transport problems solved by the discrete ordinate method, it is relatively common to observe some particularities as, for example, negative fluxes generation, slow and insecure convergences and solution instabilities. The commonly used models for neutron flux calculation and acceleration methods included in the most used codes were analyzed, in face of their use in problems characterized by a strong upscattering effect. Some special conclusions derived from this analysis are presented as well as a new method to perform the upscattering scaling for solving the before mentioned problems in this kind of cases. This method has been included in the DOT3.5 code (two dimensional discrete ordinates radiation transport code) generating a new version of wider application. (Author)
New method for calculation of integral characteristics of thermal plumes
DEFF Research Database (Denmark)
Zukowska, Daria; Popiolek, Zbigniew; Melikov, Arsen Krikor
2008-01-01
A method for calculation of integral characteristics of thermal plumes is proposed. The method allows for determination of the integral parameters of plumes based on speed measurements performed with omnidirectional low velocity thermoanemometers. The method includes a procedure for calculation of...... of a sitting occupant. The improvement in calculation of the characteristics of the thermal plume achieved with the developed method, in comparison with methods used and reported in the literature, is demonstrated....... the directional velocity (upward component of the mean velocity). The method is applied for determination of the characteristics of an asymmetric thermal plume generated by a sitting person. The method was validated in full-scale experiments in a climatic chamber with a thermal manikin as a simulator...
Methods of Measuring Competitiveness
Podaºcã Raluca
2012-01-01
Any approach to measuring competitiveness and competitive advantages must take account of one hand of the covered analysis: microeconomic, mezoeconomic, macroeconomic, and on the other hand that they are the result of many variables that are interconditioned directly or indirectly. Measurement methods attempt to quantify the impact of competitiveness and the variables considered relevant. Among all methods of measuring global competitiveness stands Global Competitiveness Index and Economic Fr...
Simulation of Quantum-Mechanical Measurements with Programmable Pocket Calculators.
Sauer, G.
1979-01-01
Described is a method for the illustration of the statistical nature of measurements in quantum physics by means of simulation with pocket calculators. The application to examples like the double-slit experiment, Mott scattering, and the demonstration of the uncertainty relation is discussed. (Author/HM)
Methods for calculating radiation attenuation in shields
International Nuclear Information System (INIS)
In recent years the development of high-speed digital computers of large capacity has revolutionized the field of reactor shield design. For compact special-purpose reactor shields, Monte-Carlo codes in two- and three dimensional geometries are now available for the proper treatment of both the neutron and gamma- ray problems. Furthermore, techniques are being developed for the theoretical optimization of minimum-weight shield configurations for this type of reactor system. In the design of land-based power reactors, on the other hand, there is a strong incentive to reduce the capital cost of the plant, and economic considerations are also relevant to reactors designed for merchant ship propulsion. In this context simple methods are needed which are economic in their data input and computing time requirements and which, at the same time, are sufficiently accurate for design work. In general the computing time required for Monte-Carlo calculations in complex geometry is excessive for routine design calculations and the capacity of the present codes is inadequate for the proper treatment of large reactor shield systems in three dimensions. In these circumstances a wide range of simpler techniques are currently being employed for design calculations. The methods of calculation for neutrons in reactor shields fall naturally into four categories: Multigroup diffusion theory; Multigroup diffusion with removal sources; Transport codes; and Monte Carlo methods. In spite of the numerous Monte- Carlo techniques which are available for penetration and back scattering, serious problems are still encountered in practice with the scattering of gamma rays from walls of buildings which contain critical facilities and also concrete-lined discharge shafts containing irradiated fuel elements. The considerable volume of data in the unclassified literature on the solution of problems of this type in civil defence work appears not to have been evaluated for reactor shield design. In
Discontinuous finite element methods for reactor calculations
International Nuclear Information System (INIS)
Variational principles which employ discontinuous shape functions for the angular and/or the spatial component of the neutron flux are established to obtain numerical solutions for neutron diffusion and transport equations. Implementing discontinuous finite element methods reduces the total nodal unknowns and hence the over all computational efforts. This reduction varies from one problem to another. In this paper one group neutron transport problems are solved by varying only the order of spherical harmonic expansion for the angular component of the flux. A comparison of the solutions obtained from the discontinuous approach with either a published solutions or a conventional finite element solutions shows that the method is a very effective tool for reactor calculations
Methods of core neutronic calculation; Methodes de calcul neutronique de coeur
Energy Technology Data Exchange (ETDEWEB)
Bruna, G.B.; Guesdon, B. [Societe Franco-Americaine de Constructions Atomiques (FRAMATOME), 92 - Paris-La-Defense (France)
1996-02-01
Core neutronic calculations lead to the determination of geometry, composition, controls systems and to the core exploitation limits in agreement with the expected performances, with safety rules, technological choices and fuel management methods. Neutronic calculations object are described with physics justifications of hypothesis and approximations. A description and a definition of reactivity and power distribution are also given. A panorama of calculation methods used in the conception of fast breeder and pressure water reactors, are described with numerical aspects and general interest considerations related to the field of these methods and to the industrial options chosen. A complete industrial uses panorama of methods derived from the classical or generalized perturbation theory is followed by the qualification and the definition of the validity field of numerical codes.(A.B.). 88 refs., 6 figs.
Calculations of EURACOS iron benchmark experiment using the HYBRID method
International Nuclear Information System (INIS)
In this paper, the HYBRID method is used in the calculations of the iron benchmark experiment at the EURACOS-II device. The saturation activities of the 32S(n,p)32P reaction at different depths in an iron block are computed with ENDF/B-IV data to compare with the measurements. At the outer layers of the iron block, the HYBRID calculation gives increasingly higher results than the VITAMIN-C multigroup calculation. With the adjustment of the two- to one-dimensional ratios, the HYBRID results agree with the measurements to within 10% at most penetration depths, a considerable improvement over the VITAMIN-C multigroup results. The development of a collapsing method for the HYBRID cross sections provides a more direct and practical way of using the HYBRID method in the two-dimensional calculations. It is observed that half of the window effect is smeared in the collapsing treatment, but it still provides a better cross-section set than the VITAMIN-C cross sections for the deep-penetration calculations
The matrix method to calculate page rank
Directory of Open Access Journals (Sweden)
H. Barboucha, M. Nasri
2014-06-01
Full Text Available Choosing the right keywords is relatively easy, whereas getting a high PageRank is more complicated. The index Page Rank is what defines the position in the result pages of search engines (for Google of course, but the other engines are now using more or less the same kind of algorithm. It is therefore very important to understand how this type of algorithm functions to hope to appear on the first page of results (the only page read in 95 % of cases or at least be among the first. We propose in this paper to clarify the operation of this algorithm using a matrix method and a JavaScript program enabling to experience this type of analysis. It is of course a simplified version, but it can add value to the website and achieve a high ranking in the search results and reach a larger customer base. The interest is to disclose an algorithm to calculate the relevance of each page. This is in fact a mathematical algorithm based on a web graph. This graph is formed of all the web pages that are modeled by nodes, and hyperlinks that are modeled by arcs.
Nuclear data and multigroup methods in fast reactor calculations
International Nuclear Information System (INIS)
The work deals with fast reactor multigroup calculations, and the efficient treatment of basic nuclear data, which serves as raw material for the calculations. Its purpose is twofold: to build a computer code system that handles a large, detailed library of basic neutron cross section data, (such as ENDF/B-III) and yields a compact set of multigroup cross sections for reactor calculations; to use the code system for comparative analysis of different libraries, in order to discover basic uncertainties that still exist in the measurement of neutron cross sections, and to determine their influence upon uncertainties in nuclear calculations. A program named NANICK which was written in two versions is presented. The first handles the American basic data library, ENDF/B-III, while the second handles the German basic data library, KEDAK. The mathematical algorithm is identical in both versions, and only the file management is different. This program calculates infinitely diluted multigroup cross sections and scattering matrices. It is complemented by the program NASIF that calculates shielding factors from resonance parameters. Different versions of NASIF were written to handle ENDF/B-III or KEDAK. New methods for evaluating in reactor calculations the long term behavior of the neutron flux as well as its fine structure are described and an efficient calculation of the shielding factors from resonance parameters is offered. (B.G.)
METHODS OF CALCULATING THE ELECTRONIC AND ATOMIC STRUCTURES OF INTERFACES
Sutton, A
1985-01-01
Methods of calculating the electronic and atomic structures of interfaces are described. An introduction to pseudopotentials and LCAO methods is given. Methods of calculating the electronic structure of an interface with a given atomic structure are considered. The feasibility of total energy calculations, in which the atomic and electronic structures are calculated simultaneously, is discussed.
Overview of multifluid-flow-calculation methods
International Nuclear Information System (INIS)
Two categories of numerical methods which may be useful in multiphase flow research are discussed. The first category includes methods which are specifically intended for accurate computation of discontinuities, such as the method of characteristics, particle-in-cell method, flux-corrected transport, and random choice methods. Methods in this category could be applied to research on rocket exhaust plumes and interior ballistics. The second category includes methods for smooth, subsonic flows, such as fractional step methods, semi-implicit method, and methods which treat convection implicitly. The subsonic flow methods could be of interest for ice flows
Method of integral transforms for calculating few-body reactions
Efros, V. D.; Leidemann, W.; Orlandini, G.
1998-01-01
A non-conventional approach to calculating reactions in quantum mechanics is presented. Reaction observables are obtained with bound state calculation techniques. The accuracy of the method to calculate few-nucleon response functions is discussed.
Calculation of skid resistance from texture measurements
Andreas Ueckermann; Dawei Wang; Markus Oeser; Bernhard Steinauer
2015-01-01
There is a wide range of routine skid resistance measurement devices on the market. All of them are measuring the friction force between a rubber wheel and the wetted road surface. Common to all of them is that they are relatively complex and costly because generally a truck carrying a large water tank is needed to wet the surface with a defined water layer. Because of the limited amount of water they can carry they are limited in range. Besides that the measurement is depending on factors li...
Method for consequence calculations for severe accidents
International Nuclear Information System (INIS)
This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Forsmark reactor No 3. The assumption used for the calculations were a 0.06% release of iodine and cesium corresponding to a 0.1% release through the FILTRA plant at Barsebaeck. The calculations were made by means of the PLUCON4 code. Meteorological data for two years from the Forsmark meteorological tower were analysed to find representative weather situations. As typical weather pasquill D was chosen with wind speed 5 m/s, and as extreme weather, Pasquill F with wind speed 2 m/s. 23 tabs., 36 ills., 21 refs. (author)
POVERTY: Stata module to calculate poverty measures
Philippe Van Kerm
1999-01-01
poverty computes a series of poverty measures based on the (income) distribution described by varname. The poverty measures that can be computed by poverty are: headcount ratio, aggregate poverty gap, poverty gap ratio, income gap ratio, Watts index, Sen index, Takayama index, Thon index, and three indices( Foster, Greer and Thorbecke; Clark et al.; and Kakwani) for various parameter values. The poverty line is either directly specified by the user or computed relative to the median of varnam...
A method to calculate Fresnel lenses
International Nuclear Information System (INIS)
In solar engineering, in contrast to image optics, Fresnel lenses are intended for securing the required concentrations of solar radiation and its distribution over a receiver's surface. It is also important to secure a high use coefficient of the concentrated flux. In particular, this defines the features of calculation of Fresnel lenses: it is necessary to take into account inaccuracies in fabrication of Fresnel lenses and solar radiation redistribution by means of selecting the respective parameters of Fresnel lens belts. In the present work, we examine the procedure for the calculating geometrical parameters of Fresnel lenses on a flat base by considering the mentioned requirements. A corresponding software for calculating the geometrical parameters and concentrating characteristics of the Fresnel lenses is developed, and examples of calculation are given. For a constant refractive index of Fresnel lens material, it is shown that the Fresnel lens can secure a concentration of about 1000, but in this case the optical efficiency of the Fresnel lens will not be higher than 70%. The procedure that has been developed may be the basic one for determining the parameters and concentrating characteristics of Fresnel lenses by considering refractive index variance. (author)
Analytic methods for calculating coupling impedances
International Nuclear Information System (INIS)
These lecture notes describe a variety of analytic techniques to calculate the longitudinal and transverse impedances of obstacles in a beam pipe. They also treat the effort to shield these impedances from the beam by appropriate use of thin conducting layers. (orig.)
Simulation of FEL pulse length calculation with THz streaking method.
Gorgisyan, I; Ischebeck, R; Prat, E; Reiche, S; Rivkin, L; Juranić, P
2016-05-01
Having accurate and comprehensive photon diagnostics for the X-ray pulses delivered by free-electron laser (FEL) facilities is of utmost importance. Along with various parameters of the photon beam (such as photon energy, beam intensity, etc.), the pulse length measurements are particularly useful both for the machine operators to measure the beam parameters and monitor the stability of the machine performance, and for the users carrying out pump-probe experiments at such facilities to better understand their measurement results. One of the most promising pulse length measurement techniques used for photon diagnostics is the THz streak camera which is capable of simultaneously measuring the lengths of the photon pulses and their arrival times with respect to the pump laser. This work presents simulations of a THz streak camera performance. The simulation procedure utilizes FEL pulses with two different photon energies in hard and soft X-ray regions, respectively. It recreates the energy spectra of the photoelectrons produced by the photon pulses and streaks them by a single-cycle THz pulse. Following the pulse-retrieval procedure of the THz streak camera, the lengths were calculated from the streaked spectra. To validate the pulse length calculation procedure, the precision and the accuracy of the method were estimated for streaking configuration corresponding to previously performed experiments. The obtained results show that for the discussed setup the method is capable of measuring FEL pulses with about a femtosecond accuracy and precision. PMID:27140142
Computational methods for probability of instability calculations
Wu, Y.-T.; Burnside, O. H.
1990-01-01
This paper summarizes the development of the methods and a computer program to compute the probability of instability of a dynamic system than can be represented by a system of second-order ordinary linear differential equations. Two instability criteria based upon the roots of the characteristics equation or Routh-Hurwitz test functions are investigated. Computational methods based on system reliability analysis methods and importance sampling concepts are proposed to perform efficient probabilistic analysis. Numerical examples are provided to demonstrate the methods.
Method for consequence calculations for severe accidents
International Nuclear Information System (INIS)
This report was commissioned by the Swedish State Power Board. The report contains a calculation of radiation doses in the surroundings caused by a theoretical core meltdown accident at Ringhals reactor No 3/4. The accident sequence chosen for the calcualtions was a release caused by total power failure. The calculations were made by means of the PLUCON4 code. A decontamination factor of 500 is used to account for the scrubber effect. Meteorological data for two years from the Ringhals meteorological tower were analysed to find representative weather situations. As typical weather, Pasquill D, was chosen with a wind speed of 10 m/s, and as extreme weather, Pasquill E, with a wind speed of 2 m/s. 19 refs. (author)
COSTS CALCULATION OF TARGET COSTING METHOD
UNGUREANU Sebastian
2014-01-01
Cost information system plays an important role in every organization in the decision making process. An important task of management is ensuring control of the operations, processes, sectors, and not ultimately on costs. Although in achieving the objectives of an organization compete more control systems (production control, quality control, etc.), the cost information system is important because monitors results of the other. Detailed analysis of costs, production cost calculation, quantifi...
Methods for calculating anisotropic transfer cross sections
International Nuclear Information System (INIS)
The Legendre moments of the group transfer cross section, which are widely used in the numerical solution of the transport calculation can be efficiently and accurately constructed from low-order (K = 1--2) successive partial range moments. This is convenient for the generation of group constants. In addition, a technique to obtain group-angle correlation transfer cross section without Legendre expansion is presented. (author)
Monte Carlo method application to shielding calculations
International Nuclear Information System (INIS)
CANDU spent fuel discharged from the reactor core contains Pu, so it must be stressed in two directions: tracing for the fuel reactivity in order to prevent critical mass formation and personnel protection during the spent fuel manipulation. The basic tasks accomplished by the shielding calculations in a nuclear safety analysis consist in dose rates calculations in order to prevent any risks both for personnel protection and impact on the environment during the spent fuel manipulation, transport and storage. To perform photon dose rates calculations the Monte Carlo MORSE-SGC code incorporated in SAS4 sequence from SCALE system was used. The paper objective was to obtain the photon dose rates to the spent fuel transport cask wall, both in radial and axial directions. As source of radiation one spent CANDU fuel bundle was used. All the geometrical and material data related to the transport cask were considered according to the shipping cask type B model, whose prototype has been realized and tested in the Institute for Nuclear Research Pitesti. (authors)
Error calculations statistics in radioactive measurements
International Nuclear Information System (INIS)
Basic approach and procedures frequently used in the practice of radioactive measurements.Statistical principles applied are part of Good radiopharmaceutical Practices and quality assurance.Concept of error, classification as systematic and random errors.Statistic fundamentals,probability theories, populations distributions, Bernoulli, Poisson,Gauss, t-test distribution,Ξ2 test, error propagation based on analysis of variance.Bibliography.z table,t-test table, Poisson index ,Ξ2 test
Spectroscopic ellipsometry data analysis: Measured vs. calculated quantities
Energy Technology Data Exchange (ETDEWEB)
Jellison, G.E. Jr.
1997-05-01
Spectroscopic ellipsometry is a very powerful technique for optical characterization of thin-film and bulk materials, but the technique measures functions of complex reflection coefficients, which are usually not of interest per se. The interesting characteristics such as film thickness, surface roughness thickness, and optical functions can be determined only by modeling the near-surface region of the sample. However, the measured quantities are not equivalent to those determined from the modeling. Ellipsometry measurements determine elements of the sample Mueller matrix, but the usual result of modeling calculations are elements of the sample. Often this difference is academic, but if the sample depolarizes the light, it is not. Ellipsometry calculations also include methods for determining the optical functions of materials. Data for bulk materials are usually accurate for substrates, but are not appropriate for most thin films. Therefore, reasonable parameterizations are quite useful in performing spectroscopic ellipsometry data analysis. Recently, there has been an increased interest in anisotropic materials, both in thin-film and bulk form. A generalized procedure will be presented for calculating the elements of the Jones matrix for any number of layers, any one of which may or may not be uniaxial.
Calculation of radon concentration in water by toluene extraction method
Energy Technology Data Exchange (ETDEWEB)
Saito, Masaaki [Tokyo Metropolitan Isotope Research Center (Japan)
1997-02-01
Noguchi method and Horiuchi method have been used as the calculation method of radon concentration in water. Both methods have two problems in the original, that is, the concentration calculated is changed by the extraction temperature depend on the incorrect solubility data and the concentration calculated are smaller than the correct values, because the radon calculation equation does not true to the gas-liquid equilibrium theory. However, the two problems are solved by improving the radon equation. I presented the Noguchi-Saito equation and the constant B of Horiuchi-Saito equation. The calculating results by the improved method showed about 10% of error. (S.Y.)
A review of calculation methods for fast and intermediate reactors
International Nuclear Information System (INIS)
This paper discusses the development of methods for calculating intermediate and fast reactors. It deals with various approaches to the problems of physical calculation. The calculation of resonance effects is discussed. Consideration is given to multi-group systems of fundamental and conjugate equations, various applications of perturbation theory to the problems of physical reactor calculation, and numerical methods of solving fundamental and conjugate reactor equations, which approximate the method of spherical harmonics. The paper describes an application of the response method to the solution of critical-mass problems, and methods of calculating reactors with hydrogeneous moderators. The fundamental features of an effective one-group reactor model are described. (author)
Benchmark calculations for evaluation methods of gas volumetric leakage rate
International Nuclear Information System (INIS)
A containment function of radioactive materials transport casks is essential for safe transportation to prevent the radioactive materials from being released into environment. Regulations such as IAEA standard determined the limit of radioactivity to be released. Since is not practical for the leakage tests to measure directly the radioactivity release from a package, as gas volumetric leakages rates are proposed in ANSI N14.5 and ISO standards. In our previous works, gas volumetric leakage rates for several kinds of gas from various leaks were measured and two evaluation methods, 'a simple evaluation method' and 'a strict evaluation method', were proposed based on the results. The simple evaluation method considers the friction loss of laminar flow with expansion effect. The strict evaluating method considers an exit loss in addition to the friction loss. In this study, four worked examples were completed for on assumed large spent fuel transport cask (Type B Package) with wet or dry capacity and at three transport conditions; normal transport with intact fuels or failed fuels, and an accident in transport. The standard leakage rates and criteria for two kinds of leak test were calculated for each example by each evaluation method. The following observations are made based upon the calculations and evaluations: the choked flow model of ANSI method greatly overestimates the criteria for tests ; the laminar flow models of both ANSI and ISO methods slightly overestimate the criteria for tests; the above two results are within the design margin for ordinary transport condition and all methods are useful for the evaluation; for severe condition such as failed fuel transportation, it should pay attention to apply a choked flow model of ANSI method. (authors)
COSTS CALCULATION OF TARGET COSTING METHOD
Directory of Open Access Journals (Sweden)
Sebastian UNGUREANU
2014-06-01
Full Text Available Cost information system plays an important role in every organization in the decision making process. An important task of management is ensuring control of the operations, processes, sectors, and not ultimately on costs. Although in achieving the objectives of an organization compete more control systems (production control, quality control, etc., the cost information system is important because monitors results of the other. Detailed analysis of costs, production cost calculation, quantification of losses, estimate the work efficiency provides a solid basis for financial control. Knowledge of the costs is a decisive factor in taking decisions and planning future activities. Managers are concerned about the costs that will appear in the future, their level underpinning the supply and production decisions as well as price policy. An important factor is the efficiency of cost information system in such a way that the information provided by it may be useful for decisions and planning of the work.
Calculating isotopic fractionation from atmospheric measurements at various scales
International Nuclear Information System (INIS)
In this paper we describe some new approaches for calculating isotopic discrimination from atmospheric measurements of CO2 and 13C. We introduce a framework that is more flexible than the traditional 'Keeling plot' two end-member mixing model, because it allows for the explicit specification of the background values of both CO2 and 13C. This approach is necessary for evaluating time series for which one can be certain that the Keeling plot requirement of stable background is violated. We also discuss a robust method for curve fitting and for estimating uncertainty of the fitting parameters. In addition to accounting for the uncertainty associated with measurements, we also account for the uncertainty associated with the appropriateness of the analytical model to the data. Our analysis suggests that uncertainty in calculated source signatures is more strongly related to the appropriateness of the model to the data than to the analytical precision of CO2 and 13C measurements. Relative to our approach, other approaches tend to underestimate the uncertainty in the fitted parameters. There can be substantial uncertainty in slopes and intercepts (two per mil or more) even if R2 is greater than 0.98. In addition, we note that fitting methods not accounting for uncertainty in both x and y result in systematic biases in the fitted parameters. Finally, we discuss the interpretation of the apparent isotopic source signature when this is a composite of several sources
Calculated and measured fields in superferric wiggler magnets
Energy Technology Data Exchange (ETDEWEB)
Blum, E.B.; Solomon, L. [Brookhaven National Lab., Upton, NY (United States)
1995-02-01
Although Klaus Halbach is widely known and appreciated as the originator of the computer program POISSON for electromagnetic field calculation, Klaus has always believed that analytical methods can give much more insight into the performance of a magnet than numerical simulation. Analytical approximations readily show how the different aspects of a magnet`s design such as pole dimensions, current, and coil configuration contribute to the performance. These methods yield accuracies of better than 10%. Analytical methods should therefore be used when conceptualizing a magnet design. Computer analysis can then be used for refinement. A simple model is presented for the peak on-axis field of an electro-magnetic wiggler with iron poles and superconducting coils. The model is applied to the radiator section of the superconducting wiggler for the BNL Harmonic Generation Free Electron Laser. The predictions of the model are compared to the measured field and the results from POISSON.
Investigation of Calculation Techniques of Finite Difference Method
Directory of Open Access Journals (Sweden)
Audrius Krukonis
2011-03-01
Full Text Available Finite difference method used for microstrip transmission line analysis is considered in this article. Paper mainly deals with iterative and bound matrix calculation techniques of finite difference method. Mathematical model for microstrip transmission line electrical potential calculations using both techniques is described. Results of characteristic impedance calculation using iterative and bound matrix techniques are presented and analyzed.Article in Lithuanian
Transportation channels calculation method in MATLAB
International Nuclear Information System (INIS)
Output devices and charged particles transport channels are necessary components of any modern particle accelerator. They differ both in sizes and in terms of focusing elements depending on particle accelerator type and its destination. A package of transport line designing codes for magnet optical channels in MATLAB environment is presented in this report. Charged particles dynamics in a focusing channel can be studied easily by means of the matrix technique. MATLAB usage is convenient because its information objects are matrixes. MATLAB allows the use the modular principle to build the software package. Program blocks are small in size and easy to use. They can be executed separately or commonly. A set of codes has a user-friendly interface. Transport channel construction consists of focusing lenses (doublets and triplets). The main of the magneto-optical channel parameters are total length and lens position and parameters of the output beam in the phase space (channel acceptance, beam emittance - beam transverse dimensions, particles divergence and image stigmaticity). Choice of the channel operation parameters is based on the conditions for satisfying mutually competing demands. And therefore the channel parameters calculation is carried out by using the search engine optimization techniques.
Dose calculation of 6 MV Truebeam using Monte Carlo method
International Nuclear Information System (INIS)
The purpose of this work is to simulate 6 MV Varian Truebeam linac dosimeter characteristics using Monte Carlo method and to investigate the availability of phase space file and the accuracy of the simulation. With the phase space file at linac window supplied by Varian to be a source, the patient-dependent part was simulated. Dose distributions in a water phantom with a 10 cm × 10 cm field were calculated and compared with measured data for validation. Evident time reduction was obtained from 4-5 h which a whole simulation cost on the same computer to around 48 minutes. Good agreement between simulations and measurements in water was observed. Dose differences are less than 3% for depth doses in build-up region and also for dose profiles inside the 80% field size, and the effect in penumbra is good. It demonstrate that the simulation using existing phase space file as the EGSnrc source is efficient. Dose differences between calculated data and measured data could meet the requirements for dose calculation. (authors)
Calculation methods for neutron radiography spatial resolution
International Nuclear Information System (INIS)
Spatial resolution is an important parameter for neutron radiography facility. In this paper, different methods to define the spatial resolution,such as point spread function (PSF), line spread function (LSF), edge spread function (ESF) and modulation transfer function (MTF), are analyzed and compared. MTF turns out to be the best, as it is derived from the linear system theory in a given frequency domain, and gives the maximum amount of useful information on system signal modulation. (authors)
Measurements and Terminology of Different Measure Methods
Institute of Scientific and Technical Information of China (English)
FANG Fang; ZHANG Wei-yuan; ZHANG Wen-bin
2005-01-01
Body measuring is very important for garment sizing and pattern making. In this paper, we study the difference of the landmarks between the traditional method and 3D scanner and we also select the 19 circumference measurements,29 height and length measurements, 18 breadth and depth measurements and 3 other measurements, which are quite important in fashion body measuring, to compare the terminology of them in these two measuring method. 3D scanners seem better than the traditional method on these aspects, which are the number of measurements, speed,privacy and data accuracy, but they are limited on measuring posture. And there is no uniform standard for the scanners and the definitions of the measurements in the scanners are diversified.
Progress and prospects of calculation methods for radiation shielding
International Nuclear Information System (INIS)
Progress in calculation methods for radiation shielding are reviewed based on the activities of research committees related to radiation shielding fields established in the Atomic Energy Society of Japan. A technological roadmap for the field of radiation shielding; progress and prospects for specific shielding calculation methods such as the Monte Carlo, discrete ordinate Sn transport, and simplified methods; and shielding experiments used to validate calculation methods are presented in this paper. (author)
49 CFR 531.6 - Measurement and calculation procedures.
2010-10-01
... the Act and set forth in 40 CFR part 600. (b) A manufacturer that is eligible to elect a model year in... 49 Transportation 6 2010-10-01 2010-10-01 false Measurement and calculation procedures. 531.6... STANDARDS § 531.6 Measurement and calculation procedures. (a) The average fuel economy of all...
49 CFR 533.6 - Measurement and calculation procedures.
2010-10-01
... 49 Transportation 6 2010-10-01 2010-10-01 false Measurement and calculation procedures. 533.6 Section 533.6 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY... Measurement and calculation procedures. (a) Any reference to a class of light trucks manufactured by...
Nodal methods in numerical reactor calculations
International Nuclear Information System (INIS)
The present work describes the antecedents, developments and applications started in 1972 with Prof. Hennart who was invited to be part of the staff of the Nuclear Engineering Department at the School of Physics and Mathematics of the National Polytechnic Institute. Since that time and up to 1981, several master theses based on classical finite element methods were developed with applications in point kinetics and in the steady state as well as the time dependent multigroup diffusion equations. After this period the emphasis moved to nodal finite elements in 1, 2 and 3D cartesian geometries. All the thesis were devoted to the numerical solution of the neutron multigroup diffusion and transport equations, few of them including the time dependence, most of them related with steady state diffusion equations. The main contributions were as follows: high order nodal schemes for the primal and mixed forms of the diffusion equations, block-centered finite-differences methods, post-processing, composite nodal finite elements for hexagons, and weakly and strongly discontinuous schemes for the transport equation. Some of these are now being used by several researchers involved in nuclear fuel management. (Author)
A new method for calculation of an air quality index
Energy Technology Data Exchange (ETDEWEB)
Ilvessalo, P. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.
1995-12-31
Air quality measurement programs in Finnish towns have expanded during the last few years. As a result of this it is more and more difficult to make use of all the measured concentration data. Citizens of Finnish towns are nowadays taking more of an interest in the air quality of their surroundings. The need to describe air quality in a simplified form has increased. Air quality indices permit the presentation of air quality data in such a way that prevailing conditions are more easily understandable than when using concentration data as such. Using an air quality index always means that some of the information about concentrations of contaminants in the air will be lost. How much information is possible to extract from a single index number depends on the calculation method. A new method for the calculation of an air quality index has been developed. This index always indicates the overstepping of an air quality guideline level. The calculation of this air quality index is performed using the concentrations of all the contaminants measured. The index gives information both about the prevailing air quality and also the short-term trend. It can also warn about the expected exceeding of guidelines due to one or several contaminants. The new index is especially suitable for the real-time monitoring and notification of air quality values. The behaviour of the index was studied using material from a measurement period in the spring of 1994 in Kaepylae, Helsinki. Material from a pre-operational period in the town of Oulu was also available. (author)
Score Calculation in Informatics Contests Using Multiple Criteria Decision Methods
Directory of Open Access Journals (Sweden)
Jurate SKUPIENE
2011-04-01
Full Text Available The Lithuanian Informatics Olympiad is a problem solving contest for high school students. The work of each contestant is evaluated in terms of several criteria, where each criterion is measured according to its own scale (but the same scale for each contestant. Several jury members are involved in the evaluation. This paper analyses the problem how to calculate the aggregated score for whole submission in the above mentioned situation. The chosen methodology for solving this problem is Multiple Criteria Decision Analysis (MCDA. The outcome of this paper is the score aggregation method proposed to be applied in LitIO developed using MCDA approaches.
Sectoring method for cosmic radiation shielding calculation for LEO satellite
International Nuclear Information System (INIS)
One of an approximate calculation model (sectoring method) is developed for a cosmic radiation shielding in satellite. Shielding calculation is performed for KITSAT-1 at the assumed SAA (South Atlatic Anomaly) location with AP-8 model radiation spectrum. When sectoring method is applied, calculation error is expected compared with 3-D detailed geometry calculation because of straight knock-on assumption neglecting the deflection of incident proton. However, sectoring method shows good agreements with 3-dimensional detailed Monte Carlo calculation in two TID detector locations
Large-scale atomic calculations using variational methods
Energy Technology Data Exchange (ETDEWEB)
Joensson, Per
1995-01-01
Atomic properties, such as radiative lifetimes, hyperfine structures and isotope shift, have been studied both theoretically and experimentally. Computer programs which calculate these properties from multiconfiguration Hartree-Fock (MCHF) and configuration interaction (CI) wave functions have been developed and tested. To study relativistic effects, a program which calculates hyperfine structures from multiconfiguration Dirac-Fock (MCDF) wave functions has also been written. A new method of dealing with radial non-orthogonalities in transition matrix elements has been investigated. This method allows two separate orbital sets to be used for the initial and final states, respectively. It is shown that, once the usual orthogonality restrictions have been overcome, systematic MCHF calculations are able to predict oscillator strengths in light atoms with high accuracy. In connection with recent high-power laser experiments, time-dependent calculations of the atomic response to intense laser fields have been performed. Using the frozen-core approximation, where the atom is modeled as an active electron moving in the average field of the core electrons and the nucleus, the active electron has been propagated in time under the influence of the laser field. Radiative lifetimes and hyperfine structures of excited states in sodium and silver have been experimentally determined using time-resolved laser spectroscopy. By recording the fluorescence light decay following laser excitation in the vacuum ultraviolet spectral region, the radiative lifetimes and hyperfine structures of the 7p{sup 2}P states in silver have been measured. The delayed-coincidence technique has been used to make very accurate measurements of the radiative lifetimes and hyperfine structures of the lowest 2P states in sodium and silver. 77 refs, 2 figs, 14 tabs.
Large-scale atomic calculations using variational methods
International Nuclear Information System (INIS)
Atomic properties, such as radiative lifetimes, hyperfine structures and isotope shift, have been studied both theoretically and experimentally. Computer programs which calculate these properties from multiconfiguration Hartree-Fock (MCHF) and configuration interaction (CI) wave functions have been developed and tested. To study relativistic effects, a program which calculates hyperfine structures from multiconfiguration Dirac-Fock (MCDF) wave functions has also been written. A new method of dealing with radial non-orthogonalities in transition matrix elements has been investigated. This method allows two separate orbital sets to be used for the initial and final states, respectively. It is shown that, once the usual orthogonality restrictions have been overcome, systematic MCHF calculations are able to predict oscillator strengths in light atoms with high accuracy. In connection with recent high-power laser experiments, time-dependent calculations of the atomic response to intense laser fields have been performed. Using the frozen-core approximation, where the atom is modeled as an active electron moving in the average field of the core electrons and the nucleus, the active electron has been propagated in time under the influence of the laser field. Radiative lifetimes and hyperfine structures of excited states in sodium and silver have been experimentally determined using time-resolved laser spectroscopy. By recording the fluorescence light decay following laser excitation in the vacuum ultraviolet spectral region, the radiative lifetimes and hyperfine structures of the 7p2P states in silver have been measured. The delayed-coincidence technique has been used to make very accurate measurements of the radiative lifetimes and hyperfine structures of the lowest 2P states in sodium and silver. 77 refs, 2 figs, 14 tabs
Force calculations and measurements of electro-magnetic chuck
International Nuclear Information System (INIS)
The attraction forces between a test piece and a square type electromagnetic chuck, which is used for settling the work piece by electromagnetic force to grind the work piece on it, are calculated and measured. To calculate and to measure the attraction forces precisely, the gap, chuck-test piece distance, is set at 0.010 - 0.25 mm. Linear and nonlinear force calculations are carried out using the measured material characteristics. The obtained forces are compared with the measured ones. Introducing proper material characteristics are necessary to obtain accurate attraction force. (Author)
MEASURING OF COMPLEX STRUCTURE TRANSFER FUNCTION AND CALCULATING OF INNER SOUND FIELD
Institute of Scientific and Technical Information of China (English)
Chen Yuan; Huang Qibai; Shi Hanmin
2005-01-01
In order to measure complex structure transfer function and calculate inner sound field, transfer function of integration is mentioned. By establishing virtual system, transfer function of integration can be measured and the inner sound field can also be calculated. In the experiment, automobile body transfer function of integration is measured and experimental method of establishing virtual system is very valid.
Quantum Monte Carlo diagonalization method as a variational calculation
Energy Technology Data Exchange (ETDEWEB)
Mizusaki, Takahiro; Otsuka, Takaharu [Tokyo Univ. (Japan). Dept. of Physics; Honma, Michio
1997-05-01
A stochastic method for performing large-scale shell model calculations is presented, which utilizes the auxiliary field Monte Carlo technique and diagonalization method. This method overcomes the limitation of the conventional shell model diagonalization and can extremely widen the feasibility of shell model calculations with realistic interactions for spectroscopic study of nuclear structure. (author)
Study on increasing calculation precision and convergence speed of streamline strip element method
Institute of Scientific and Technical Information of China (English)
彭艳; 刘宏民
2004-01-01
The calculation precision and convergence speed of streamline strip element method are increased by using the method whose initial value of the exit lateral displacement is determined with strip element variation method, and the accurate tension lateral distribution model is adopted based on the original third power spline function streamline strip element method. The basic theory of the strip element method is developed. The calculated results by the improved streamline strip element method and the original streamline strip element method are compared with the measured results, showing that the calculated results of the improved method are in good agreement with the measured results.
Methods of speed measurement. Geschwindigkeitsmessverfahren
Energy Technology Data Exchange (ETDEWEB)
Baeumer, K.; Rath, K.; Rogge, H.; Wiegand, H.
1990-09-27
In a method, i.e. the operation of a device for contactless measurement of speeds, speed-time curves and decay frequencies in liquid jets and flames two light beams emitted by strong light source are focussed in such a way in the measured volume of a fluid layer or flame layer that the light transmission in the measured volume can be measured at a focal distance
The TAB method for numerical calculation of spray droplet breakup
Orourke, P. J.; Amsden, A. A.
A short history is given of the major milestones in the development of the stochastic particle method for calculating liquid fuel sprays. The most recent advance has been the discovery of the importance of drop breakup in engine sprays. A new method, called TAB, for calculating drop breakup is presented. Some theoretical properties of the method are derived; its numerical implementation in the computer program KIVA is described; and comparisons are presented between TAB-method calculations and experiments and calculations using another breakup model.
Hotel Competitiveness Measurement Methods
Katalin Juhasz-Dora
2015-01-01
Competitiveness is becoming a very common expression used in business administration. The definition and its application still raises some questions due to the complexity of its meaning. The role of the measurement of competitiveness and its effect on performance and profitability is increasing in the field of hospitality and tourism as well. The measurement of hotel competitiveness is a current issue in business life due to globalization, sharing economy and the change in the consumber habit...
Calculation and measurement of depth dose distributions in bricks
International Nuclear Information System (INIS)
The dose accumulated in bricks exposed to gamma radiation can be measured as a function of depth using luminescence methods. The dependence of dose on depth has the potential of providing information on the energy as well as on the angular distribution of the incident radiation, which could give indications on the configuration of the radiation sources. A prerequisite for such an analysis is a comprehensive knowledge on the dependence of dose on depth for different source energies and for specific source configurations. Depth dose distribution in brick walls have been calculated by Monte Carlo simulations for a source distribution on a wall, for a source distribution on the ground and for a parallel photon beam, for source energies ranging from 140 keV to 1600 keV. It is shown that depth dose distributions depend substantially on source configuration and energy. Depth dose distributions measured in ceramic materials irradiated in the laboratory and in a brick from a contaminated area are compared with results of Monte Carlo calculations. (Author)
Martian Radiation Environment: Model Calculations and Recent Measurements with "MARIE"
Saganti, P. B.; Cucinotta, F. A.; zeitlin, C. J.; Cleghorn, T. F.
2004-01-01
The Galactic Cosmic Ray spectra in Mars orbit were generated with the recently expanded HZETRN (High Z and Energy Transport) and QMSFRG (Quantum Multiple-Scattering theory of nuclear Fragmentation) model calculations. These model calculations are compared with the first eighteen months of measured data from the MARIE (Martian Radiation Environment Experiment) instrument onboard the 2001 Mars Odyssey spacecraft that is currently in Martian orbit. The dose rates observed by the MARIE instrument are within 10% of the model calculated predictions. Model calculations are compared with the MARIE measurements of dose, dose-equivalent values, along with the available particle flux distribution. Model calculated particle flux includes GCR elemental composition of atomic number, Z = 1-28 and mass number, A = 1-58. Particle flux calculations specific for the current MARIE mapping period are reviewed and presented.
Comments on Simplified Calculation Method for Fire Exposed Concrete Columns
DEFF Research Database (Denmark)
Hertz, Kristian Dahl
1998-01-01
The author has developed new simplified calculation methods for fire exposed columns. Methods, which are found In ENV 1992-1-2 chapter 4.3 and in proposal for Danish code of Practise DS411 chapter 9. In the present supporting document the methods are derived and 50 eccentrically loaded fire exposed...... columns are calculated and compared to results of full-scale tests. Furthermore 500 columns are calculated in order to present each test result related to a variation of the calculation in time of fire resistance....
A Damping Characteristics Calculation Method of Metal Dry Friction Isolators
Institute of Scientific and Technical Information of China (English)
JIANG Hong-yuan; HAO De-gang; XIA Yu-hong; ULANOV A M; PONOMAREV Yu K
2008-01-01
The dry friction ring-type vibration isolator is considered as an isotropic continuous medium. A method of dry friction hysteresis loop calculation is proposed based on friction force analysis of contact beam. The friction force is modeled as an equivalent distributed moment to use the finite element method (FEM) to calculate the dry friction vibration isolator hysteresis loop, so the damping characteristics can be obtained. A comparison of the hysteresis loop calculation results and the experimental results shows the average relative error is 2.7%, it proves the calculation method is feasible.
Method for calculating annual energy efficiency improvement of TV sets
Energy Technology Data Exchange (ETDEWEB)
Varman, M. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Mahlia, T.M.I. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)]. E-mail: indra@um.edu.my; Masjuki, H.H. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)
2006-10-15
The popularization of 24 h pay-TV, interactive video games, web-TV, VCD and DVD are poised to have a large impact on overall TV electricity consumption in the Malaysia. Following this increased consumption, energy efficiency standard present a highly effective measure for decreasing electricity consumption in the residential sector. The main problem in setting energy efficiency standard is identifying annual efficiency improvement, due to the lack of time series statistical data available in developing countries. This study attempts to present a method of calculating annual energy efficiency improvement for TV set, which can be used for implementing energy efficiency standard for TV sets in Malaysia and other developing countries. Although the presented result is only an approximation, definitely it is one of the ways of accomplishing energy standard. Furthermore, the method can be used for other appliances without any major modification.
Method for calculating annual energy efficiency improvement of TV sets
International Nuclear Information System (INIS)
The popularization of 24 h pay-TV, interactive video games, web-TV, VCD and DVD are poised to have a large impact on overall TV electricity consumption in the Malaysia. Following this increased consumption, energy efficiency standard present a highly effective measure for decreasing electricity consumption in the residential sector. The main problem in setting energy efficiency standard is identifying annual efficiency improvement, due to the lack of time series statistical data available in developing countries. This study attempts to present a method of calculating annual energy efficiency improvement for TV set, which can be used for implementing energy efficiency standard for TV sets in Malaysia and other developing countries. Although the presented result is only an approximation, definitely it is one of the ways of accomplishing energy standard. Furthermore, the method can be used for other appliances without any major modification
Some methods for calculation of perturbations in nuclear reactors
Energy Technology Data Exchange (ETDEWEB)
Abramov, B. D., E-mail: abramov@ippe.ru [Leypunsky Institute of Physics and Power Engineering (Russian Federation)
2015-12-15
Some methods for calculation of local perturbations of neutron fields and reactivity effects accompanying them are considered. Existence, uniqueness, properties and methods for finding solutions to the considered problems are discussed.
Evolution of calculation methods taking into account severe accidents
International Nuclear Information System (INIS)
During the first decade of PWRs operation in France the calculation methods used for design and operation have improved very much. This paper gives a general analysis of the calculation methods evolution in parallel with the evolution of safety approach concerning PWRs. Then a comprehensive presentation of principal calculation tools is presented as applied during the past decade. An effort is done to predict the improvements in near future
Aoki, Hirooki; Ichimura, Shiro; Fujiwara, Toyoki; Kiyooka, Satoru; Koshiji, Kohji; Tsuzuki, Keishi; Nakamura, Hidetoshi; Fujimoto, Hideo
We proposed a calculation method of the ventilation threshold using the non-contact respiration measurement with dot-matrix pattern light projection under pedaling exercise. The validity and effectiveness of our proposed method is examined by simultaneous measurement with the expiration gas analyzer. The experimental result showed that the correlation existed between the quasi ventilation thresholds calculated by our proposed method and the ventilation thresholds calculated by the expiration gas analyzer. This result indicates the possibility of the non-contact measurement of the ventilation threshold by the proposed method.
A New Method for Calculating the Thermoelectric Efficiency
Institute of Scientific and Technical Information of China (English)
吴一东; 王志敏; 何元金
2004-01-01
We present an approximate method for calculating the thermoelectric effciency. The method has a high precision and is applicable to almost all of the thermoelectric devices. The expression for the thermoelectric efficiency we obtained does not involve the position variable, so the calculations are simplified greatly.
Calculation of transonic flows using an extended integral equation method
Nixon, D.
1976-01-01
An extended integral equation method for transonic flows is developed. In the extended integral equation method velocities in the flow field are calculated in addition to values on the aerofoil surface, in contrast with the less accurate 'standard' integral equation method in which only surface velocities are calculated. The results obtained for aerofoils in subcritical flow and in supercritical flow when shock waves are present compare satisfactorily with the results of recent finite difference methods.
Iterative acceleration methods for Monte Carlo and deterministic criticality calculations
International Nuclear Information System (INIS)
If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors
Iterative acceleration methods for Monte Carlo and deterministic criticality calculations
Energy Technology Data Exchange (ETDEWEB)
Urbatsch, T.J.
1995-11-01
If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors.
Approximate design calculation methods for radiation streaming in shield irregularities
International Nuclear Information System (INIS)
Investigation and assessment are made for approximate design calculation methods of radiation streaming in shield irregularities. Investigation is made for (1) source, (2) definition of streaming radiation components, (3) calculation methods of streaming radiation, (4) streaming formulas for each irregularity, (5) difficulties in application of streaming formulas, etc. Furthermore, investigation is made for simple calculation codes and albedo data. As a result, it is clarified that streaming calculation formulas are not enough to cover various irregularities and their accuracy or application limit is not sufficiently clear. Accurate treatment is not made in the formulas with respect to the radiation behavior for slant incidence, bend part, offset etc., that results in too much safety factors in the design calculation and distrust of the streaming calculation. To overcome the state and improve the accuracy of the design calculation for shield irregularities, it is emphasized to assess existing formulas and develop better formulas based on systematic experimental studies. (author)
Directory of Open Access Journals (Sweden)
CarloAlberto Redi
2010-09-01
Full Text Available Rightly stressed by prof. Wolfgang Walz in the Preface to the series Neuromethods series, the “careful application of methods is probably the most important step in the process of scientific inquiry”. Thus, I strongly suggest to all those interested in calcium signaling and especially to the new-comers in the hot topic of neuroscience (which has so much space even in science-society debate for its implications in legal issues and in the judge-decision process to take profit from this so well edited book. I am saying this since prof. Verkhratsky and prof. Petersen......
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The improved form of calculation formula for the activities of the components in binary liquids and solid alloys has been derived based on the free volume theory considering excess entropy and Miedema's model for calculating the formation heat of binary alloys. A calculation method of excess thermodynamic functions for binary alloys, the formulas of integral molar excess properties and partial molar excess properties for solid ordered or disordered binary alloys have been developed. The calculated results are in good agreement with the experimental values.
A finite element method for SSI time history calculation
International Nuclear Information System (INIS)
The method which is proposed is based on a finite element modelization for the soil and the structure and a time history calculation. It has been developed for plane and axisymmetric geometries. The principle of this method is presented, then applications are given, first to a linear calculation for which results will be compared to those obtained by standard methods. Then results for a non linear behavior are described
Ore reserve calculation methods used by Eldorado Nuclear Limited
International Nuclear Information System (INIS)
Uranium-bearing pitchblende deposits of the Beaverlodge area in northern Saskatchewan are highly complex. The ideas and concepts of ore reserve calculation methods employed by Eldorado Nuclear Limited in assessing and planning the mining of these deposits are described. A manual block-system of ore reserve calculation was used before the adoption of the current computerized system. Four classifications are used for ore reserves calculated by the system, which provides two main program jobs for calculating ore reserves and several additional ones that involve calculations and graphical presentation of ore reserve information for use in mine planning. A comparison of production statistics and ore reserve calculations illustrates the accuracy of the method. (author)
Comparison of calculational methods for EBT reactor nucleonics
International Nuclear Information System (INIS)
Nucleonic calculations for a preliminary conceptual design of the first wall/blanket/shield/coil assembly for an EBT reactor are described. Two-dimensional Monte Carlo, and one- and two-dimensional discrete-ordinates calculations are compared. Good agreement for the calculated values of tritium breeding and nuclear heating is seen. We find that the three methods are all useful and complementary as a design of this type evolves
Elongation method for electronic structure calculations of random DNA sequences.
Orimoto, Yuuichi; Liu, Kai; Aoki, Yuriko
2015-10-30
We applied ab initio order-N elongation (ELG) method to calculate electronic structures of various deoxyribonucleic acid (DNA) models. We aim to test potential application of the method for building a database of DNA electronic structures. The ELG method mimics polymerization reactions on a computer and meets the requirements for linear scaling computational efficiency and high accuracy, even for huge systems. As a benchmark test, we applied the method for calculations of various types of random sequenced A- and B-type DNA models with and without counterions. In each case, the ELG method maintained high accuracy with small errors in energy on the order of 10(-8) hartree/atom compared with conventional calculations. We demonstrate that the ELG method can provide valuable information such as stabilization energies and local densities of states for each DNA sequence. In addition, we discuss the "restarting" feature of the ELG method for constructing a database that exhaustively covers DNA species. PMID:26337429
Fluid-structure interaction calculations using a linear perturbation method
International Nuclear Information System (INIS)
Aim of the work is to present and validate FSI (Fluid-Structure Interaction) calculations by using a linear perturbation method and commercial Computational Fluid Dynamics (CFD) and structural analysis codes. Star-CD is used for CFD calculations and ABAQUS for structural analysis. The external MpCCI code is used for coupling the CFD and structural analysis codes
Methods for Measuring Aggregate Costs of Conflict
Gardeazabal, Javier
2010-01-01
This paper reviews the methods for measuring the economic cost of conflict. Estimating the economic costs of conflict requires a counterfactual calculation, which makes this a very difficult task. Social researchers have resorted to different estimation methods depending on the particular effect in question. The method used in each case depends on the units being analyzed (firms, sectors, regions or countries), the outcome variable under study (aggregate output, market valuation of firms, mar...
Protein-protein binding affinities calculated using the LIE method
Andberg, Tor Arne Heim
2011-01-01
Absolute binding free energies for the third domain of the turkey ovomucoid inhibitor in complex with Streptomyces griseus proteinase B and porcine pancreatic elastase has been calculated using the linear interaction energy method.
A new method to calculate hole subbands of semiconductors hetrostructures
International Nuclear Information System (INIS)
A new method, ordinary boundary method (OBM), is suggested to calculate the hole subbands and wavefunctions of semiconductor hetrostructures. Based on it, a transfer matrix is established. By means of it not only the hole subbands and wavefunctions of hetrostructures can be calculated rigorously and quickly but also the asymptotic transfer method can be generalized to calculate the hole subbands of complex systems in which the valence bandedges are oblique lines or curves. As examples we calculated the hole subbands of GaAs/AlxGa1-xAs quantum well and GaAs/AlxGa1-xAs superlattice in terms of both OBM and transfer matrix method. (author). 7 refs, 4 figs
A valid method of calculating virtual scene depth
Institute of Scientific and Technical Information of China (English)
QUAN Hong-yan; ZHANG Tian-wen; LIN Xiang-hong
2005-01-01
A valid method of virtual scene depth calculating is put forward. In this method cameras rotate in three different viewpoints in the plane and we calculate the depth of panorama using three stitching cylinder panoramas. In the investigation, the column of panorama is regarded as a slot image. Using the conic intersected by the epipolar plane and the cylinder, we can obtain the perpendicularity disparity. In order to obtain dense correspondence fast and accurately, a new method of obtaining horizontal disparity using depth continuity is also put forward. It converts the problem of panorama dense correspondence to the problem of searching points in the conic. The occlusion problem is dealt with using three cylinders in the depth calculation. It is verified that this method is convenient, useful and efficient in calculating the depth of a virtual scene.
Comparison study on cell calculation method of fast reactor
International Nuclear Information System (INIS)
Effective cross sections obtained by cell calculations are used in core calculations in current deterministic methods. Therefore, it is important to calculate the effective cross sections accurately and several methods have been proposed. In this study, some of the methods are compared to each other using a continuous energy Monte Carlo method as a reference. The result shows that the table look-up method used in Japan Nuclear Cycle Development Institute (JNC) sometimes has a difference over 10% in effective microscopic cross sections and be inferior to the sub-group method. The problem was overcome by introducing a new nuclear constant system developed in JNC, in which the ultra free energy group library is used. The system can also deal with resonance interaction effects between nuclides which are not able to be considered by other methods. In addition, a new method was proposed to calculate effective cross section accurately for power reactor fuel subassembly where the new nuclear constant system cannot be applied. This method uses the sub-group method and the ultra fine energy group collision probability method. The microscopic effective cross sections obtained by this method agree with the reference values within 5% difference. (author)
Seismic response based on transient calculations. Spectral and stochastic methods
International Nuclear Information System (INIS)
Further to the recent development in the ASTER code of functionalities enabling random dynamic responses to be calculated, notably a stochastic type seismic analysis, we propose a combination of three calculation methods to estimate a probabilistic seismic response on an N4 reactor building stick-model. Transient calculations involves time-and cost-consuming repetition. The conventional oscillator response spectrum calculation yields only the maximum response expectation. On the other hand, the stochastic approach in this context gives the response corresponding to selected probabilities. (authors). 12 figs., 3 tabs., 4 refs
Methods for tornado frequency calculation of nuclear power plant
International Nuclear Information System (INIS)
In order to take probabilistic safety assessment of nuclear power plant tornado attack event, a method to calculate tornado frequency of nuclear power plant is introduced based on HAD 101/10 and NUREG/CR-4839 references. This method can consider history tornado frequency of the plant area, construction dimension, intensity various along with tornado path and area distribution and so on and calculate the frequency of different scale tornado. (authors)
Calculating expected deaths: a comparison of two methods.
Chovil, A C
1987-01-01
A comparison is presented between the traditional "person-years" and more recently described "prospective model" methods for calculating mortality expectations. Problems arising from the fact that expectations under the person-years method are calculated on the basis that a null hypothesis is true, which results in artificial figures that, at least theoretically, are meaningless if the hypothesis is rejected, are discussed. Data are presented from two studies in which expectations have been c...
CALCULATION OF COMPANY COSTS THROUGH THE DIRECT-COSTING CALCULATION METHOD
Directory of Open Access Journals (Sweden)
Florin-Constantin DIMA
2013-06-01
Full Text Available The cost of production has as its starting point the purchase cost of raw materials and consumables, as well as their processing cost and the calculation of the production cost involves complex aspects. This article is based on the two major concepts of costs calculation, namely the concept of full costs and the concept of partial costs, and it analyses the direct-costing calculation method. Necessity of the Development of calculation methods to ensure rapid determination of the cost of production, and the establishment of indicators broad spectrum of information necessary for making decisions to streamline a business activity conducted by direct-costing method. Direct-costing method appeared in the U.S. for the first time in 1934 (applied by Jonathan Harris and G. Charter Harrison. Subsequently, this method was applied to European countries (England, France, Germany etc.. We stopped on this method because it is considered a modern method of costing. Therefore, we analyzed both advantages and limitations of the method in question
International Nuclear Information System (INIS)
This paper addresses the problem of calculating the bioimpedance phase angle from measurements of impedance modulus. A complete impedance measurement was performed on altogether 20 healthy persons using a Solatron 1260/1294 system. The obtained impedance modulus (absolute impedance value) values were used to calculate the Cole parameters and from them the phase angles. In addition, the phase angles were also calculated using a Kramers–Kronig approach. A correlation analysis for all subjects at each frequency (5, 50, 100 and 200 kHz) for both methods gave R2 values ranging from 0.7 to 0.96 for the Cole approach and from 0.83 to 0.96 for the Kramers–Kronig approach; thus, both methods gave good results compared with the complete measurement results. From further statistical significance testing of the absolute value of the difference between measured and calculated phase angles, it was found that the Cole equation method gave significantly better agreement for the 50 and 100 kHz frequencies. In addition, the Cole equation method gives the four Cole parameters (R0, R∞, τz and α) using measurements at frequencies up to 200 kHz while the Kramers–Kronig method used frequencies up to 500 kHz to reduce the effect of truncation on the calculated results. Both methods gave results that can be used for further bioimpedance calculations, thus improving the application potential of bioimpedance measurement results obtained using relatively inexpensive and portable measurement equipment
Simplified hourly method to calculate summer temperatures in dwellings
DEFF Research Database (Denmark)
Mortensen, Lone Hedegaard; Aggerholm, Søren
2012-01-01
with further simplifications. The method is used for calculating room temperatures for all hours of a reference year. It is essential that the simplified method is able to predict the temperature in the room with the highest heat load. The heat load is influenced by the solar load, internal load...... and solar load. The developed method can calculate the number of hours above a given temperature limit. The limits are a prerequisite for the development of the simplified method, and a supplementary maximum temperature limit is suggested to ensure robustness. The setting of the ventilation rate is...
Automated methods of corrosion measurement
DEFF Research Database (Denmark)
Andersen, Jens Enevold Thaulov; Bech-Nielsen, Gregers; Reeve, John Ch;
1997-01-01
to revise assumptions regarding the basis of the method, which sometimes leads to the discovery of as-yet unnoticed phenomena. The present selection of automated methods for corrosion measurements is not motivated simply by the fact that a certain measurement can be performed automatically...
Calculation methods for SPF for heat pump systems for comparison, system choice and dimensioning
Energy Technology Data Exchange (ETDEWEB)
Nordman, Roger; Andersson, Kajsa; Axell, Monica; Lindahl, Markus
2010-09-15
In this project, results from field measurements of heat pumps have been collected and summarised. Also existing calculation methods have been compared and summarised. Analyses have been made on how the field measurements compare to existing calculation models for heat pumps Seasonal Performance Factor (SPF), and what deviations may depend on. Recommendations for new calculation models are proposed, which include combined systems (e.g. solar - HP), capacity controlled heat pumps and combined DHW and heating operation
Development of 3-D detailed FBR core calculation method based on method of characteristics
International Nuclear Information System (INIS)
A new detailed 3-D transport calculation method taking into account the heterogeneity of fuel assemblies has been developed in hexagonal-z geometry by combining the method of characteristics (MOC) and the nodal transport method. From the nodal transport calculation which uses assembly homogenized cross sections, the axial leakage is calculated, and it is used for the MOC calculation which treats the heterogeneity of fuel assemblies. Series of homogeneous MOC calculations which use assembly homogeneous cross sections are carried out to obtain effective cross sections, which preserve assembly reaction rates. This effective cross sections are again used in the 3-dimensional nodal transport calculation. The numerical calculations have been performed to verify 3-dimensional radial calculations of FBR (fast breeder reactor) assemblies and partial core calculations. Results are compared with the reference Monte-Carlo calculations. A good agreement has been achieved. It is shown that the present method has an advantage in calculating reaction rates in a small region. (authors)
Comparison of MCNPX and Albedo method in criticality calculation
International Nuclear Information System (INIS)
This study aims to conduct a computer simulation that will calculate the reactivity of a homogeneous reactor and compare the results with the calculations made by the albedo method. The simulation will be developed using the MCNPX. The study compared the results calculated for a hypothetical reactor by the albedo method for four groups of energy with those obtained by the MCNPX simulation. The design of the reactor is spherical and homogeneous with a reflector of finite thickness. The value obtained for the neutron effective multiplication factor - keff will be compared. Different situations were simulated in order to obtain results closer to the compared method and reality. The was Good consistency could be noticed between the calculated results. (author)
Calculation method for gamma dose rates from Gaussian puffs
International Nuclear Information System (INIS)
The Lagrangian puff models are widely used for calculation of the dispersion of releases to the atmosphere. Basic output from such models is concentration of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on the semi-infinite cloud model. This method is however only applicable for puffs with large dispersion parameters, i.e. for receptors far away from the release point. The exact calculation of the cloud dose using volume integral requires large computer time usually exceeding what is available for real time calculations. The volume integral for gamma doses could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor because only a few of the relevant parameters are considered. A multi-parameter method for calculation of gamma doses is described here. This method uses precalculated values of the gamma dose rates as a function of Eγ, σy, the asymmetry factor - σy/σz, the height of puff center - H and the distance from puff center Rxy. To accelerate the calculations the release energy, for each significant radionuclide in each energy group, has been calculated and tabulated. Based on the precalculated values and suitable interpolation procedure the calculation of gamma doses needs only short computing time and it is almost independent of the number of radionuclides considered. (au) 2 tabs., 15 ills., 12 refs
Air quality along motorways. Measuring and modelling calculations
International Nuclear Information System (INIS)
This report describes the air quality along Koege Bugt motorway, one of the most trafficked sections in Denmark. A number of measurements have been carried out along Koege Bugt motorway at Greve for a three-month period in the autumn of 2003. For the first time in Denmark, NOx were measured with high time dissolution from different distances of the motorway. Furthermore, a number of meteorological parameters were measured in order to map local meteorological conditions. An air quality model describing dispersal and conversion has been made on the basis of the OML model. The OML model is modified in order to take traffic-made turbulence into consideration. The model has been evaluated through comparisons between measurements and simulated calculations. Furthermore, simulated calculations for the year 2003 has been made for comparison with extreme values. (BA)
The PCA replica experiment. Part I: Winfrith measurements and calculations
International Nuclear Information System (INIS)
This paper gives the results of all measurements which have been processed to date and the results of corresponding Monte Carlo predictions made with McBEND. Some sensitivity coefficients given by the DUCKPOND (4) module in McBEND are also given. Other measurements have been made by collaborators from HEDL (US), SCK/CEN (Mol, Belgium) and BNL (UK). These will be given, together with attribution, in Part 11 of this paper in which a full analysis of both the REPLICA and PCA experiments will be presented. This analysis waits upon further McBEND calculations in the PCA experiment to reduce the statistical uncertainties in the calculations to the point where they are not dominant contributors to the total calculational uncertainties
Measurements and theoretical calculations of diffused radiation and atmosphere lucidity
International Nuclear Information System (INIS)
Align with other environment friendly renewable energy sources solar energy is widely used in the world. Also in Latvia solar collectors are used. However, in Latvia because of its geographical and climatic conditions there are some specific features in comparison with traditional solar energy using countries. These features lead to the necessity to pay more attention to diffused irradiance. Another factor affecting the received irradiance of any surface is lucidity of atmosphere. This factor has not been studied in Latvia yet. This article deals with evaluation of diffused irradiance, and also of lucidity of atmosphere. The diffused irradiance can be measured directly or as a difference between the global irradiance and the beam one. The lucidity of atmosphere can be calculated from the measurements of both global and beam irradiance, if the height of the sun is known. Therefore, measurements of both global and beam irradiance have been carried out, and the diffused irradiance calculated as a difference between the global irradiance and the beam one. For measuring of the global irradiance the dome solarimeter has been used. For measuring of the direct irradiance tracking to sun pirheliometer has been used. The measurements were performed in Riga from October 2008 till March 2009. The measurements were executed automatically after every 5 minutes. The obtained results have been analyzed taking into account also the data on nebulosity from the State agency Latvian Environment, Geology and Meteorology Agency. Also efforts to calculate theoretically the diffused irradiance from the height of the sun and the data of the nebulosity have been done. These calculated values have been compared with the measured ones. Good accordance is obtained. (author)
Calculation method for gamma-dose rates from spherical puffs
International Nuclear Information System (INIS)
The Lagrangian puff-models are widely used for calculation of the dispersion of atmospheric releases. Basic output from such models are concentrations of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on semi-infinite cloud model. This method is however only applicable for points far away from the release point. The exact calculation of the cloud dose using the volume integral requires significant computer time. The volume integral for the gamma dose could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor due to the fact that the same correction factors are used for all isotopes. The authors describe a more elaborate correction method. This method uses precalculated values of the gamma-dose rate as a function of the puff dispersion parameter (δp) and the distance from the puff centre for four energy groups. The release of energy for each radionuclide in each energy group has been calculated and tabulated. Based on these tables and a suitable interpolation procedure the calculation of gamma doses takes very short time and is almost independent of the number of radionuclides. (au) (7 tabs., 7 ills., 12 refs.)
International Nuclear Information System (INIS)
According to the acceptance of ICRP Publication 60 (1990), the dose equivalent limit for the boarder of controlled area will be defined as 1.3 mSv/3 months in the Regulation for the Enforcement of the Medical Service Law which is scheduled to be revised. The calculating methods of radiation shielding to be considered are as follows: The first method is calculating the dose equivalent for each nuclide using 3-month maximum estimated use dose. The second method is calculating the dose equivalent using 3-month maximum estimated use dose after the conversion of all nuclide dose into that of 131I. The third method is calculating the dose equivalent using 1 day maximum estimated use dose after the conversion of all nuclide dose into that of 131I. We've investigated which of methods can meet the new regulation value (1.3 mSv/3 months). In modeled facility, we've tried to calculate the dose by the first method to confirm if we can perform the reasonable control in safe. Total dose equivalent for the boarder of controlled area (B) was 883 μSv/3 months by the first method, and its value turned out to be about 1/4 of that of the third method. Only the result by the first method was found to be within the confines of new dose equivalent limit of 1.3 mSv/3 months. The results of both method the second and the third were found to be within the confines of existing dose equivalent limit. The method as to calculate the shielding for each nuclide by using 3-month maximum estimated use dose has been accepted in the Law Concerning Prevention from Radiation Hazards due to Radioisotopes, etc. As the method is practically in accordance with the current use of radioisotope in nuclear medicine facility, the possibility of it coping with the new dose equivalent limit was indicated. (author)
Application of nonparametric statistic method for DNBR limit calculation
International Nuclear Information System (INIS)
Background: Nonparametric statistical method is a kind of statistical inference method not depending on a certain distribution; it calculates the tolerance limits under certain probability level and confidence through sampling methods. The DNBR margin is one important parameter of NPP design, which presents the safety level of NPP. Purpose and Methods: This paper uses nonparametric statistical method basing on Wilks formula and VIPER-01 subchannel analysis code to calculate the DNBR design limits (DL) of 300 MW NPP (Nuclear Power Plant) during the complete loss of flow accident, simultaneously compared with the DL of DNBR through means of ITDP to get certain DNBR margin. Results: The results indicate that this method can gain 2.96% DNBR margin more than that obtained by ITDP methodology. Conclusions: Because of the reduction of the conservation during analysis process, the nonparametric statistical method can provide greater DNBR margin and the increase of DNBR margin is benefited for the upgrading of core refuel scheme. (authors)
Measurement, calculation and evaluation of photon production cross-sections
International Nuclear Information System (INIS)
The meeting proceedings were divided into three sessions devoted to the following topics: Experimental measurement and techniques (3 papers), calculation of photon cross-sections (9 papers), and evaluation (2 papers). A separate abstract was prepared for each of these papers. Refs, figs and tabs
A simple method for calculating Clebsch-Gordan coefficients
Energy Technology Data Exchange (ETDEWEB)
Klink, W H; Wickramasekara, S, E-mail: william-klink@uiowa.ed, E-mail: wickrama@grinnell.ed, E-mail: s-wickram@uiowa.ed [Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52242 (United States)
2010-09-15
This paper presents a simple method for calculating Clebsch-Gordan coefficients for the tensor product of two unitary irreducible representations (UIRs) of the rotation group. The method also works for multiplicity-free irreducible representations appearing in the tensor product of any number of UIRs of the rotation group. The generalization to representations with multiplicity is straightforward and briefly discussed.
Efficient Calculation of Near Fields in the FDTD Method
DEFF Research Database (Denmark)
Franek, Ondrej
2011-01-01
When calculating frequency-domain near fields by the FDTD method, almost 50 % reduction in memory and CPU operations can be achieved if only E-fields are stored during the main time-stepping loop and H-fields computed later. An improved method of obtaining the H-fields from Faraday's Law is...
New methods for neutron response calculations with MCNP
International Nuclear Information System (INIS)
MCNP4B was released for international distribution in February, 1997. The author summarized the new MCNP4B features since the release of MCNP4A over three years earlier and compare some results. Then he describes new methods being developed for future code releases. The focus is methods and applications of ex-core neutron response calculations
Experimental verification of a recursive method to calculate evapotranspiration
Recently, a recursive combination method (RCM) to calculate potential and crop evapotranspiration (ET) was given by Lascano and Van Bavel (Agron. J. 2007, 99:585–590). The RCM differs from the Penman-Monteith (PM) method, the main difference being that the assumptions made regarding the temperature ...
Calculation of Solar Radiation by Using Regression Methods
Kızıltan, Ö.; Şahin, M.
2016-04-01
In this study, solar radiation was estimated at 53 location over Turkey with varying climatic conditions using the Linear, Ridge, Lasso, Smoother, Partial least, KNN and Gaussian process regression methods. The data of 2002 and 2003 years were used to obtain regression coefficients of relevant methods. The coefficients were obtained based on the input parameters. Input parameters were month, altitude, latitude, longitude and landsurface temperature (LST).The values for LST were obtained from the data of the National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA-AVHRR) satellite. Solar radiation was calculated using obtained coefficients in regression methods for 2004 year. The results were compared statistically. The most successful method was Gaussian process regression method. The most unsuccessful method was lasso regression method. While means bias error (MBE) value of Gaussian process regression method was 0,274 MJ/m2, root mean square error (RMSE) value of method was calculated as 2,260 MJ/m2. The correlation coefficient of related method was calculated as 0,941. Statistical results are consistent with the literature. Used the Gaussian process regression method is recommended for other studies.
Benchmark calculations for hexagonal lattices with different methods
International Nuclear Information System (INIS)
Necessity to increase the safety conditions of exploitation of recently designed core of modern nuclear reactors causes stronger requirements to the precision of neutron-physical analysis. To get more precise characteristics of nuclear reactor cells and assembly one can increase the accuracy of neutron-physical calculation analysis by taking account the spectral effects. This paper deals with the analysis of the ZR-6 series of experiments using some components of the KARATE code system. The goal of our investigations is the comparison of measured and calculated parameters of perturbed hexagonal lattices containing Gd2O3 in Al2O3 matrix or water holes/ The quoted results include: the critical y parameters Hcr, dρ/dh and the absorber rod efficiency: Δρ. The experiments are based on doubling time measurements. The calculations have been compared not only to the measured data but to the Monte Carlo code results, too (Authors)
On-line reactivity calculation using Lagrange method
International Nuclear Information System (INIS)
Highlights: • Lagrange method is proposed for on-line reactivity calculation in nuclear reactors. • The need for nuclear power history or the Laplace transform is vanished. • The three- and five-point formulas are presented and examined in different benchmark cases. • Computational time-steps of up to 1 s lead to highly reliable reactivity calculations. • The main advantage of the proposed approach is its stability and convergence in large time-step calculations. - Abstract: In this paper, a novel multi-step method is proposed for solving the inverse point kinetics problem using Lagrange polynomial method. By use of this approach, the need for nuclear power history or the Laplace transform is vanished. Furthermore, the accuracy of the method is of order hn for the (n + 1)-point formula, where h is the computational time-step. The three- and five-point formulas of the Lagrange method are used for on-line reactivity calculations and results are benchmarked against reference solutions for different nuclear power forms. Moreover, results for different computational time-steps are compared in each case. The results show the accuracy of the proposed method in all benchmarking cases. For slow transients (large reactor periods), it is shown that time-steps of up to 1 s lead to highly reliable reactivity calculations. However, the optimal time-step in almost all cases is shown to be 0.1 s. The main advantage of the proposed approach, in contrast with previous numerical methods, is its stability and convergence in large time-step calculations. The proposed method can be used as real time reactivity meter in all nuclear reactors without limitation of nuclear power form
Calculating atomic and molecular properties using variational Monte Carlo methods
International Nuclear Information System (INIS)
The authors compute a number of properties for the 1 1S, 21S, and 23S states of helium as well as the ground states of H2 and H/+3 using Variational Monte Carlo. These are in good agreement with previous calculations (where available). Electric-response constants for the ground states of helium, H2 and H+3 are computed as derivatives of the total energy. The method used to calculate these quantities is discussed in detail
Refinement of thermal imager minimum resolvable temperature difference calculating method
Kolobrodov, V. G.; Mykytenko, V. I.
2015-11-01
Calculating methods, which accurately predict minimum resolvable temperature difference (MRTD), are of significant interest for many years. The article deals with improvement the accuracy of determining the thermal imaging system MRTD by elaboration the visual perception model. We suggest MRTD calculating algorithm, which is based on a reliable approximation of the human visual system modulation transfer function (MTF) proposed by N. Nill. There was obtained a new expression for the bandwidth evaluation, which is independent of angular size of the Foucault bar target.
The analytic method for calculating the control rod worth
International Nuclear Information System (INIS)
We calculated the control rod worth in this paper. To avoid complexity, we did not consider burnable poisons and soluble boron. The system was localized within one assembly. The control rod was treated as not an absorber but an another boundary. Thus all of the group constants were unchanged before and after control rod insertion. And we discussed the method for calculation of the reactivity of the whole core
Neutron transport calculations using Quasi-Monte Carlo methods
Energy Technology Data Exchange (ETDEWEB)
Moskowitz, B.S.
1997-07-01
This paper examines the use of quasirandom sequences of points in place of pseudorandom points in Monte Carlo neutron transport calculations. For two simple demonstration problems, the root mean square error, computed over a set of repeated runs, is found to be significantly less when quasirandom sequences are used ({open_quotes}Quasi-Monte Carlo Method{close_quotes}) than when a standard Monte Carlo calculation is performed using only pseudorandom points.
Calculated and measured emittance of sputter-type negative-ion source
International Nuclear Information System (INIS)
A method for calculating the beam current and emittance of a negative ion beam from a sputter-type source is described. Calculations are compared to measured emittance. The dependence of the emittance on ion source parameters such as cathode shape, exit aperture diameter, and cathode voltage is discussed
Shape integral method for magnetospheric shapes. [boundary layer calculations
Michel, F. C.
1979-01-01
A method is developed for calculating the shape of any magnetopause to arbitrarily high precision. The method uses an integral equation which is evaluated for a trial shape. The resulting values of the integral equation as a function of auxiliary variables indicate how close one is to the desired solution. A variational method can then be used to improve the trial shape. Some potential applications are briefly mentioned.
THE INTEGRAL FORMULA FOR CALCULATING THE HAUSDORFF MEASURE OF SOME FRACTAL SETS
Institute of Scientific and Technical Information of China (English)
Lu Shipan; Su Weiyi
2001-01-01
It is important to calculate the Hausdor ff dimen sion and the Hausdor ff mesare res pect to this dimension for some f ractal sets. By using the usual method of “Mass Distribution”, we can only calculate the Hausdor f f dimesion. In this paper , we will construct an integral farmla by using lower inverse s-density and then use it to calculate the Hausdor f f measures for some fractional dimensional sets.
International Nuclear Information System (INIS)
The computer code based on the described method was designed including calculation of conversion factors for user defined depth distribution models. Inputs of the code are peak areas of the considered radionuclides energy lines (measured in the given arrangement and calculated by any spectra analysis software), known or expected depth distribution models for individual radionuclides (including user defined models) and soil density. The activity concentrations of considered radionuclides and depth distribution models are calculated by the code. Described method was successfully tested and is used for processing of in-situ gamma spectrometry data measured by the spectrometer with semiconductor detector
Calculation and comparative measurement of a manipulator boom
International Nuclear Information System (INIS)
A manipulator system is fabricated for the use in a fusion reactor. The system allows to take in any arbitrary position in a plane. It consists of seven linked arms. During resting position, the manipulator boom is folded together in an antechamber. For the working position, the individual links are moved out through the opening to operate in a ring-shaped vacuum vessel. The stress analysis of the boom follows three steps: calculation of the global forces with a beam model dependent on the different working positions of the boom; calculation of the local stresses in the jointed arms with Finite-Element-Models for the worst load combination; and comparison of the calculations with strain gauge measurements
Calculating High Speed Centrifugal Compressor Performance from Averaged Measurements
Lou, Fangyuan; Fleming, Ryan; Key, Nicole L.
2012-12-01
To improve the understanding of high performance centrifugal compressors found in modern aircraft engines, the aerodynamics through these machines must be experimentally studied. To accurately capture the complex flow phenomena through these devices, research facilities that can accurately simulate these flows are necessary. One such facility has been recently developed, and it is used in this paper to explore the effects of averaging total pressure and total temperature measurements to calculate compressor performance. Different averaging techniques (including area averaging, mass averaging, and work averaging) have been applied to the data. Results show that there is a negligible difference in both the calculated total pressure ratio and efficiency for the different techniques employed. However, the uncertainty in the performance parameters calculated with the different averaging techniques is significantly different, with area averaging providing the least uncertainty.
Improvement of fitting method of multiband parameters for cell calculations
International Nuclear Information System (INIS)
To accurately perform cell calculations of nuclear reactors, a new fitting procedure has been developed for calculating multiband parameters, which are necessary for effective cross section calculations. By using the new fitting procedure, the error of multiband parameters becomes always zero. Reactor cell calculations have been performed to compare the effective cross sections and the infinite multiplication factors etc. calculated using the multiband parameters obtained by the new and the conventional fitting procedures by using the cross section set based on the JENDL-3.1 library with 107 energy groups. It is found that there is a small difference of the calculational results between the two fitting procedures and it is found from burnup calculations that the difference of the infinite multiplication factors is not dependent on the burnup period up to about 30 GWd/t. The onion skin effect can be exactly treated by dividing a fuel pellet to multiple regions and by using the multiband method. Thus the difference of burnup properties between two fitting procedures are investigated for the divided and the undivided fueled cells. The total inventory of Pu, Am etc. at the divided case is almost the same to the undivided case at the end of the burnup period. However it is found that the radial distribution of atomic density is slightly different between the two fitting procedures. (author)
Composite electron propagator methods for calculating ionization energies
Díaz-Tinoco, Manuel; Dolgounitcheva, O.; Zakrzewski, V. G.; Ortiz, J. V.
2016-06-01
Accurate ionization energies of molecules may be determined efficiently with composite electron-propagator (CEP) techniques. These methods estimate the results of a calculation with an advanced correlation method and a large basis set by performing a series of more tractable calculations in which large basis sets are used with simpler approximations and small basis sets are paired with more demanding correlation techniques. The performance of several CEP methods, in which diagonal, second-order electron propagator results with large basis sets are combined with higher-order results obtained with smaller basis sets, has been tested for the ionization energies of closed-shell molecules from the G2 set. Useful compromises of accuracy and computational efficiency employ complete-basis-set extrapolation for second-order results and small basis sets in third-order, partial third-order, renormalized partial-third order, or outer valence Green's function calculations. Analysis of results for vertical as well as adiabatic ionization energies leads to specific recommendations on the best use of regular and composite methods. Results for 22 organic molecules of interest in the design of photovoltaic devices, benzo[a]pyrene, Mg-octaethylporphyrin, and C60 illustrate the capabilities of CEP methods for calculations on large molecules.
Composite electron propagator methods for calculating ionization energies.
Díaz-Tinoco, Manuel; Dolgounitcheva, O; Zakrzewski, V G; Ortiz, J V
2016-06-14
Accurate ionization energies of molecules may be determined efficiently with composite electron-propagator (CEP) techniques. These methods estimate the results of a calculation with an advanced correlation method and a large basis set by performing a series of more tractable calculations in which large basis sets are used with simpler approximations and small basis sets are paired with more demanding correlation techniques. The performance of several CEP methods, in which diagonal, second-order electron propagator results with large basis sets are combined with higher-order results obtained with smaller basis sets, has been tested for the ionization energies of closed-shell molecules from the G2 set. Useful compromises of accuracy and computational efficiency employ complete-basis-set extrapolation for second-order results and small basis sets in third-order, partial third-order, renormalized partial-third order, or outer valence Green's function calculations. Analysis of results for vertical as well as adiabatic ionization energies leads to specific recommendations on the best use of regular and composite methods. Results for 22 organic molecules of interest in the design of photovoltaic devices, benzo[a]pyrene, Mg-octaethylporphyrin, and C60 illustrate the capabilities of CEP methods for calculations on large molecules. PMID:27305999
Solar opacity calculations using the super-transition-array method
Krief, M; Gazit, D
2016-01-01
An opacity model based on the Super-Transition-Array (STA) method for the calculation of monochromatic opacities of local thermodynamic equilibrium plasmas was developed. The model is described and used to calculate spectral opacities for a solar model implementing the recent AGSS09 composition. Calculations are carried throughout the solar radiative zone. The relative contributions of different chemical elements and photon-matter processes to the total Rosseland mean opacity are analyzed in detail. Monochromatic opacities and charge state distributions were compared with the widely used Opacity-Project (OP) code, for several elements near the radiation-convection interface. STA Rosseland opacities for the solar mixture show a very good agreement with OP and the OPAL opacity code, throughout the radiation zone. Finally, an explicit STA calculation of the full AGSS09 photospheric mixture, including all heavy metals was performed. It was shown that due to their extremely low abundance, and despite being very go...
Comparison of measured and calculated peripheral doses in patients undergoing radiation therapy
International Nuclear Information System (INIS)
Background and purpose: Many papers have been published on the measurement for specific treatment machines and/or techniques of the dose to points outside the primary beam, often called the peripheral dose (PD). Most papers concern measurements in phantoms. We report on the results of a comparison of estimates of the PD, based on these phantom measurements, with PDs measured on patients. Material and methods: A special holder with thermoluminescent dosimeters was placed against the perineum of patients referred to our institute for radiation therapy. The measured dose was then compared with the dose calculated on the basis of published PD data. Results: For all measurements together, the calculated values exceeded the measured PDs by about 9%, with a standard deviation of 35%. The correlation varied between specific subgroups but the difference between measurement and calculation did not exceed 50%. Conclusions: We conclude that published PD data can be used to accurately predict the peripheral dose in the clinical situation
A method to calculate displacement factors using SVM
Institute of Scientific and Technical Information of China (English)
Li Peixian; Tan Zhixiang; Yan Lili; Deng Kazhong
2011-01-01
In order to improve the precision of mining subsidence prediction,a mathematical model using Support Vector Machine (SVM) was established to calculate the displacement factor.The study is based on a comprehensive analysis of factors affecting the displacement factor,such as mechanical properties of the cover rock,the ratio of mining depth to seam thickness,dip angle of the coal seam and the thickness of loose layer.Data of 63 typical observation stations were used as a training and testing sample set.A SVM regression model of the displacement factor and the factors affecting it was established with a kernel function,an insensitive loss factor and a properly selected penalty factor.Given an accurate calculation algorithm for testing and analysis,the results show that an SVM regression model can calculate displacement factor precisely and reliable precision can be obtained which meets engineering requirements.The experimental results show that the method to calculation of the displacement factor,based on the SVM method,is feasible.The many factors affecting the displacement factor can be considered with this method.The research provides an efficient and accurate approach for the calculation of displacement in mining subsidence prediction.
Using A Particular Sampling Method for Impedance Measurement
Directory of Open Access Journals (Sweden)
Lentka Grzegorz
2014-08-01
Full Text Available The paper presents an impedance measurement method using a particular sampling method which is an alternative to DFT calculation. The method uses a sine excitation signal and sampling response signals proportional to current flowing through and voltage across the measured impedance. The object impedance is calculated without using Fourier transform. The method was first evaluated in MATLAB by means of simulation. The method was then practically verified in a constructed simple impedance measurement instrument based on a PSoC (Programmable System on Chip. The obtained calculation simplification recommends the method for implementation in simple portable impedance analyzers destined for operation in the field or embedding in sensors.
Benjamin Whang; Gilbert, William E.; Stephen Zilliacus
1994-01-01
Two visually meaningful correlation measures are proposed for comparing calculated and measured response histories. One is an error index which is a simplification of RSS (root-sum-square) error factor, and the other is an inequality index that is a simplification of Theil’s inequality coefficient. The first compares the difference between the calculated and the measured histories to the measured history. The second compares the difference between the two histories to the sum of the two. The ...
A New Method to Calculate Internal Rate of Return
Directory of Open Access Journals (Sweden)
azadeh zandi
2015-09-01
Full Text Available A number of methods have been developed to choose the best capital investment projects such as net present value, internal rate of return and etc. Internal rate of return method is probably the most popular method among managers and investors. But despite the popularity there are serious drawbacks and limitations in this method. After decades of efforts made by economists and experts to improve the method and its shortcomings, Magni in 2010 has revealed a new approach that can solves the most of internal rate of return method problems. This paper present a new method which is originated from Magni’s approach but has much more simple calculations and can resolve all the drawbacks of internal rate of return method.
Optimization method for quantitative calculation of clay minerals in soil
Indian Academy of Sciences (India)
Libo Hao; Qiaoqiao Wei; Yuyan Zhao; Zilong Lu; Xinyun Zhao
2015-04-01
Determination of types and amounts for clay minerals in soil are important in environmental, agricultural, and geological investigations. Many reliable methods have been established to identify clay mineral types. However, no reliable method for quantitative analysis of clay minerals has been established so far. In this study, an attempt was made to propose an optimization method for the quantitative determination of clay minerals in soil based on bulk chemical composition data. The fundamental principles and processes of the calculation are elucidated. Some samples were used for reliability verification of the method and the results prove the simplicity and efficacy of the approach.
Measured and calculated isotopes for a gadolinia lead test assembly
International Nuclear Information System (INIS)
The US Department of Energy, Duke Power Company, and the B and W Fuel Company participated in an extended burnup project to develop, irradiate, and examine an advanced fuel assembly design for pressurized water reactors. The assembly uses a urania-gadolinia (UO2-Gd2O3) burnable absorber fuel mixture along with other fuel performance and design features that enhance uranium utilization. Previous milestones in the gadolinia development of the extended burnup project include development and verification of a neutronics model, measurement of materials properties of gadolinia fuel, and a successful gadolinia lead test assembly (LTA) program. One LTA was discharged as planned after one cycle, four LTAs continued for two more cycles, and one LTA of these four underwent a fourth cycle and reached 58,310 MWd/ton U assembly-average burnup, a world record at the time. Hot-cell destructive examination of gadolinia and non-gadolinia fuel rods from the single-cycle LTA (406.2 effective full-power days irradiation) has been completed. The comparison of measured and calculated isotopics for this LTA is the subject of this paper. A comparison of measured and calculated power distributions is also given, because accurate prediction of core performance during power production is ultimately the most important test of a calculational model
Investigation of methods used in calculations of solar cell parameters
Shvets, E. Ya.; Khrypko, S. L.; Zubko, E. I.
2009-01-01
Analytical expressions have been obtained for extracting the electrical parameters and characteristics of solar cells, including series and shunt resistances, and the saturation current. The method of Lagrange multipliers was used for computing the shape factor of the current–voltage characteristic (CVC) of solar cell. The calculation results demonstrated a satisfactory agreement with experimental data.
Emergy Algebra: Improving Matrix Methods for Calculating Tranformities
Transformity is one of the core concepts in Energy Systems Theory and it is fundamental to the calculation of emergy. Accurate evaluation of transformities and other emergy per unit values is essential for the broad acceptance, application and further development of emergy method...
Thick-Restart Lanczos Method for Electronic Structure Calculations
International Nuclear Information System (INIS)
This paper describes two recent innovations related to the classic Lanczos method for eigenvalue problems, namely the thick-restart technique and dynamic restarting schemes. Combining these two new techniques we are able to implement an efficient eigenvalue problem solver. This paper will demonstrate its effectiveness on one particular class of problems for which this method is well suited: linear eigenvalue problems generated from non-self-consistent electronic structure calculations
Using A Particular Sampling Method for Impedance Measurement
Lentka Grzegorz
2014-01-01
The paper presents an impedance measurement method using a particular sampling method which is an alternative to DFT calculation. The method uses a sine excitation signal and sampling response signals proportional to current flowing through and voltage across the measured impedance. The object impedance is calculated without using Fourier transform. The method was first evaluated in MATLAB by means of simulation. The method was then practically verified in a constructed simple impedance measu...
Theories and calculation methods for regional objective ET (evapotranspiration): Applications
Institute of Scientific and Technical Information of China (English)
LIU diaHong; QIN DaYong; WANG MingNa; L(U) JinYan; SANG XueFeng; ZHANG RuiMei
2009-01-01
The regional objective ET (evapotranspiration) is defined as the quantity of water that could be con-sumed in a particular region. It varies with the water conditions and economic development stages in the region. It is also constrained by the requirement of benign environment cycle. At the same time, it must meet the demands of sustainable economic growth and the construction of harmony society.Objective ET based water resources distribution will replace the conventional method, which empha-sizes the balance between the water demand and the water supply. It puts focus on the reasonable water consumption instead of the forecasted water demand, which is usually greater than the actual one. In this paper, we calculated the objective ET of 2010 year level in Tianjin by an analysis-integra-tion-assessment method. Objective ET can be classified into two parts: controllable ET and uncontrol-lable ET. Controllable ET includes the ET from irrigation land and the ET from resident land, among which the former can be calculated with soil moisture model and evapotranspiration model, while the latter can be calculated by water use ration and water consumption rate. The uncontrollable ET can be calculated with the distributed hydrological model and the remote sensing monitoring model. The two models can be mutually calibrated. In this paper, eight schemes are put forward based on different portfolios of water resources. The objective ET of each scheme was calculated and the results were assessed and analyzed. Finally, an optimal scheme was recommended.
Triangulation methods in engineering measurement
Kyle, S. A.
1988-01-01
Industrial surveying and photogrammetry are being increasingly applied to the measurement of engineering objects which have typical dimensions in the range 2-100 metres. Both techniques are examples of the principle of triangulation. By applying photocrammetric concepts to surveying methods and vice-versa, a general approach is established which has a number of advantages. In particular. alternative strategies for constructing and analysing measurement networks are dev...
Studies on the calculation method of regional solar radiation
International Nuclear Information System (INIS)
Studies on the Calculation Method of Regional Solar Radiation 1. The significance and question of regional solar radiation The significance of regional solar radiation in agriculture is clear. To estimate regional agricultural producing potential, we need to know the regional solar radiation. In the field of hydrology, regional solar radiation is also important to estimate evapotranspiration of the region. There are so many slopes with different slope angles and slope directions in a region. So, we have to know how we can calculate slope radiation. The conversion
Load calculation methods for offshore wind turbine foundations
DEFF Research Database (Denmark)
Passon, Patrik; Branner, Kim
2014-01-01
turbine manufacturer provides the FD with dynamic responses obtained from aeroelastic simulations at a predefined interface. These responses are subsequently expanded to the corresponding dynamic responses in all structural parts of the foundation. In this article, a novel load calculation method, for the......Calculation of design loads for offshore wind turbine (OWT) foundations is typically performed in a joint effort between wind turbine manufactures and foundation designers (FDs). Ideally, both parties would apply the same fully integrated design tool and model for that purpose. However, such...
Slab Storage Calculation Method for Continuous Casting-Hot Rolling
Institute of Scientific and Technical Information of China (English)
PENG Qi-chun; LIU Qing; TIAN Nai-yuan
2004-01-01
Based on load-oriented manufacturing control theory, different combining modes and slab storage calculation method for continuous casting and hot rolling were discussed. The buffer capacity index of continuous casting-rolling was introduced, and the reasonable slab storage under different combining modes was calculated with buffer capacity index of 120.00 h for CCR, 79.20 h for HCR, 19.68 h for DHCR and 3.84 h for DR. Thin slab is 1.20 h, and the strip is zero. Theory gist was provided for steel enterprise to decrease storage.
A new method for the automatic calculation of prosody
International Nuclear Information System (INIS)
An algorithm is presented for the calculation of the prosodic parameters for speech synthesis. It uses the melodic patterns, composed of rising and falling slopes, suggested by G. CAELEN, and rests on: 1. An analysis into units of meaning to determine a melodic pattern 2. the calculation of the numeric values for the prosodic variations of each syllable; 3. The use of a table of vocalic values for the three parameters for each vowel according to the consonantal environment and of a table of standard duration for consonants. This method was applied in the 'SARA' program of synthesis with satisfactory results. (author)
Short circuit currents calculation by using the impedance correction method
Energy Technology Data Exchange (ETDEWEB)
Schaefer, W.
1985-01-01
By introduction of correction factors for the impedances of generators and power station unit transformers into the known guidings according to VDE 0102 (basis principle of short circuit current calculation) it is possible to limit the deviation to less then +-5% of the value of the complete superposition method apart from some exceptions. The correction factors are valid for calculation of the maximum short circuit currents considering the practically admissible operating conditions. The separated correction of the impedances of generators and power station unit transformers can be used without restriction for all short circuit points of interest.
Simplified method for trace anomaly calculations in d≤6
International Nuclear Information System (INIS)
We discuss a simplified method for computing trace anomalies in dimensions d≤6. It is known that in the quantum mechanical approach trace anomalies in d dimensions are given by a (d/2+1)-loop computation in an auxiliary 1D sigma model with arbitrary geometry. We show how one can obtain the same information using a simpler (d/2)-loop calculation on an arbitrary geometry supplemented by a (d/2+1)-loop calculation on the simplified geometry of a maximally symmetric space
Refinement of the substructure method for integral transport calculations
International Nuclear Information System (INIS)
A new generalization of the interface-current method for coupling two-dimensional heterogeneous assemblies, called substructures, has been developed. The method has been designed for fine-structure burnup calculations in large, very heterogeneous media. For the calculations, the medium is divided into rectangular substructures, which can have internal symmetries, containing rectangular and/or cylindrical structure elements, divided into homogeneous zones. A zonewise flat or linear expansion is used to formulate a direct collision-probability problem within each substructure. The substructures are coupled by making a piecewise uniform or linear expansion for the partial currents entering and leaving the substructures. The method has also been used to implement an approximate piecewise isotropic reflection for two-dimensional x-y collision probabilities calculations. The accuracies and computing times achieved are illustrated by one-group fixed-source numerical calculations for a typical 7 x 7 pin pressurized water reactor assembly as well as for a set of fuel slabs imbedded in a water moderator
Calculation of interface curvature with the level-set method
Lervåg, Karl Yngve
2014-01-01
The level-set method is a popular method for interface capturing. One of the advantages of the level-set method is that the curvature and the normal vector of the interface can be readily calculated from the level-set function. However, in cases where the level-set method is used to capture topological changes, the standard discretization techniques for the curvature and the normal vector do not work properly. This is because they are affected by the discontinuities of the signed-distance function half-way between two interfaces. This article addresses the calculation of normal vectors and curvatures with the level-set method for such cases. It presents a discretization scheme that is relatively easy to implement in to an existing code. The improved discretization scheme is compared with a standard discretization scheme, first for a case with no flow, then for a case where two drops collide in a shear flow. The results show that the improved discretization yields more robust calculations in areas where topolo...
Accelerating molecular property calculations with nonorthonormal Krylov space methods
Furche, Filipp; Krull, Brandon T.; Nguyen, Brian D.; Kwon, Jake
2016-05-01
We formulate Krylov space methods for large eigenvalue problems and linear equation systems that take advantage of decreasing residual norms to reduce the cost of matrix-vector multiplication. The residuals are used as subspace basis without prior orthonormalization, which leads to generalized eigenvalue problems or linear equation systems on the Krylov space. These nonorthonormal Krylov space (nKs) algorithms are favorable for large matrices with irregular sparsity patterns whose elements are computed on the fly, because fewer operations are necessary as the residual norm decreases as compared to the conventional method, while errors in the desired eigenpairs and solution vectors remain small. We consider real symmetric and symplectic eigenvalue problems as well as linear equation systems and Sylvester equations as they appear in configuration interaction and response theory. The nKs method can be implemented in existing electronic structure codes with minor modifications and yields speed-ups of 1.2-1.8 in typical time-dependent Hartree-Fock and density functional applications without accuracy loss. The algorithm can compute entire linear subspaces simultaneously which benefits electronic spectra and force constant calculations requiring many eigenpairs or solution vectors. The nKs approach is related to difference density methods in electronic ground state calculations and particularly efficient for integral direct computations of exchange-type contractions. By combination with resolution-of-the-identity methods for Coulomb contractions, three- to fivefold speed-ups of hybrid time-dependent density functional excited state and response calculations are achieved.
An economical method to calculate eigenvalues of the Schroedinger equation
International Nuclear Information System (INIS)
A method is presented which is an extension to negative energies of a spectral integral equation method to solve the Schroedinger equation, developed previously for scattering applications. One important innovation is a re-scaling procedure in order to compensate for the exponential behaviour of the negative energy Green's function. Another is the need to find approximate energy eigenvalues, to serve as starting values for a subsequent iteration procedure. In order to illustrate the new method, the binding energy of the He-He dimer is calculated, using the He-He TTY potential. In view of the small value of the binding energy, the wavefunction has to be calculated to a distance of 3000 au. Two hundred and twenty mesh points were sufficient to obtain an accuracy of three significant figures for the binding energy, and with 320 mesh points the accuracy increased to six significant figures. An application to a potential with two wells, separated by a barrier, is also made
Measurement and calculation of gamma ray transport in concrete
International Nuclear Information System (INIS)
A gamma-ray spectroscopy system using a 5-cm by 5-cm NE-213 organic scintillator was used for the measurement of gamma-ray pulse-height spectra behind four concrete slabs of different thickness. The pulse-height data was fed to the Tsing-Hua gamma-ray response matrix coupled with FORIST code to evaluate the experimental spectra. The experimental results were compared to ANISN discrete ordinates calculations. The ANISN calculations used DLC-23E data library with 22 neutron and 18 gamma-ray groups. The experimental and numerical results were in good agreement for 30 cm and 40 cm concrete slabs in the energy ranging from 0.1 MeV to 0.7 MeV, and large disagreement was evident for 10 cm and 20 cm slabs. The calculated fluxes overpredicted the measurements. At upper energies namely between 0.4 - 0.7 MeV, very good agreement was obtained for the four concrete slabs. The main source of disagreement was due to Tsing-Hua response matrix and poor modeling of one dimensional code. 36 Ref
Radiation protection, measurements and methods
International Nuclear Information System (INIS)
The introductory lectures discuss subjects such as radiation protection principles and appropriate measuring techniques; methods, quantities and units in radiation protection measurement; technical equipment; national and international radiation protection standards. The papers presented at the various sessions deal with: Dosimetry of external radiation (27 papers); Working environment monitoring and emission monitoring (21 contributions); Environmental monitoring (19 papers); Incorporation monitoring (9 papers); Detection limits (4 papers); Non-ionizing radiation, measurement of body dose and biological dosimetry (10 papers). All 94 contributions (lectures, compacts and posters) are retrievable as separate records. (HP)
Calculation of Turbulent Boundary Layers Using the Dissipation Integral Method
Institute of Scientific and Technical Information of China (English)
MatthiasBuschmann
1999-01-01
This paper gives an introduction into the dissipation integral method.The general integral equations for the three-dimensional case are derved.It is found that for a practical calculation algorithm the integral monentum equation and the integral energy equation are msot useful.Using Two different sets of mean velocity profiles the hyperbolical character of a dissipation integral method is shown.Test cases for two-and three-dimensional boundary layers are analysed and discussed.The paper concludes with a discussion of the advantages and limits of dissipation integral methods.
Analytical methods to calculate correlation functions in quantum statistical physics
International Nuclear Information System (INIS)
In the work there is presented a brief but clear and quite reserved account of two analytical methods to calculate correlation functions in quantum statistical physics, proceeding from the first principles, i.e., the most broadly used at present two-time temperature Green's functions method and a new, so-called 'direct algebraic' method (DAM). The aim of this work is to show on the concrete examples of live the most broadly used models of quantum statistical physics, mathematical and technical clarity and simplicity of DAM and hence its practical value
Comparison between calculation methods of dose rates in gynecologic brachytherapy
International Nuclear Information System (INIS)
In treatments with radiations for gynecologic tumors is necessary to evaluate the quality of the results obtained by different calculation methods for the dose rates on the points of clinical interest (A, rectal, vesicle). The present work compares the results obtained by two methods. The Manual Calibration Method (MCM) tri dimensional (Vianello E., et.al. 1998), using orthogonal radiographs for each patient in treatment, and the Theraplan/T P-11 planning system (Thratonics International Limited 1990) this last one verified experimentally (Vianello et.al. 1996). The results show that MCM can be used in the physical-clinical practice with a percentile difference comparable at the computerized programs. (Author)
Radiation Environment Variations at Mars - Model Calculations and Measurements
Saganti, Premkumar; Cucinotta, Francis
Variations in the space radiation environment due to changes in the GCR (Galactic Cosmic Ray) from the past (#23) solar cycle to the current one (#24) has been intriguing in many ways, with an unprecedented long duration of the recent solar minimum condition and a very low peak activity of the current solar maximum. Model calculated radiation data and assessment of variations in the particle flux - protons, alpha particles, and heavy ions of the GCR environment is essential for understanding radiation risk and for any future intended long-duration human exploration missions. During the past solar cycle, we have had most active and higher solar maximum (2001-2003) condition. In the beginning of the current solar cycle (#24), we experienced a very long duration of solar minimum (2009-2011) condition with a lower peak activity (2013-2014). At Mars, radiation measurements in orbit were obtained (onboard the 2001 Mars Odyssey spacecraft) during the past (#23) solar maximum condition. Radiation measurements on the surface of Mars are being currently measured (onboard the Mars Science Laboratory, 2012 - Curiosity) during the current (#24) solar peak activity (August 2012 - present). We present our model calculated radiation environment at Mars during solar maxima for solar cycles #23 and #24. We compare our earlier model calculations (Cucinotta et al., J. Radiat. Res., 43, S35-S39, 2002; Saganti et al., J. Radiat. Res., 43, S119-S124, 2002; and Saganti et al., Space Science Reviews, 110, 143-156, 2004) with the most recent radiation measurements on the surface of Mars (2012 - present).
Artificial Boundary Method for Calculating Ship Wave Resistance
Institute of Scientific and Technical Information of China (English)
文新; 韩厚德
2003-01-01
The calculation of wave resistance for a ship moving at constant speed near a free surface is considered. This wave resistance is calculated with a linearized steady potential model. To deal with the unboundedness of the physical domain in the potential flow problem, we introduce one vertical side as an artificial upstream boundary and two vertical sides as the artificial downstream boundaries. On the artificial boundaries, a sequence of high-order global artificial boundary conditions are given. Then the potential flow problem is reduced to a problem defined on a finite computational domain, which is equivalent to a variational problem. The solution of the variational problem by the finite element method gives the numerical approximation of the potential flow around the ship, which was used to calculate the wave resistance. The numerical examples show the accuracy and efficiency of the proposed numerical scheme.
International Nuclear Information System (INIS)
Count loss by wall effect was calculated with EGS4 code. Calculated results agreed well with experimental results measured with pressure extrapolation method. In this calculation AE, AP and ECUT, PCUT are better to be set at lower values. Because EGS4 code is not so suited for very low energy of beta-ray, for those samples which emit beta-rays with lower energy than 14C, EGS4 is unsuited to be used for calculation of wall effect. (J.P.N.)
Calculation of statistical entropic measures in a model of solids
International Nuclear Information System (INIS)
In this work, a one-dimensional model of crystalline solids based on the Dirac comb limit of the Krönig–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. -- Highlights: ► A simplified model of solids is considered. Its electronic band structure is calculated. ► The statistical complexity and the Fisher–Shannon information are computed on this model. ► The extremal value for this indicators are taken on the configurations showing the highest conductivity.
Calculation of statistical entropic measures in a model of solids
Energy Technology Data Exchange (ETDEWEB)
Sañudo, Jaime, E-mail: jsr@unex.es [Departamento de Física, Facultad de Ciencias, Universidad de Extremadura, E-06071 Badajoz (Spain); BIFI, Universidad de Zaragoza, E-50009 Zaragoza (Spain); López-Ruiz, Ricardo, E-mail: rilopez@unizar.es [DIIS and BIFI, Facultad de Ciencias, Universidad de Zaragoza, E-50009 Zaragoza (Spain)
2012-07-09
In this work, a one-dimensional model of crystalline solids based on the Dirac comb limit of the Krönig–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. -- Highlights: ► A simplified model of solids is considered. Its electronic band structure is calculated. ► The statistical complexity and the Fisher–Shannon information are computed on this model. ► The extremal value for this indicators are taken on the configurations showing the highest conductivity.
International Nuclear Information System (INIS)
The maximum power of a reactor is limited by the power peaking factor. During the design stage it is calculated with neutronic calculation codes. This is not enough for ensuring its value due to modelling approximations. For the RA-6s low enrichment new core a calculus-measurement correlation method have been applied. Position and magnitude of the maximum power density estimated by calculus are used by this method. For this work 249 cooper-gold alloy (1.55% Au) wires have been distributed along the core using 19 aluminium blades. Their positions have been selected using information given by a 5 groups PUMA reactor model. Wire s activity have been measured with a HPGe detector. Gold activity have been used only for verifying the calculated core spectrum. The measured power peaking factor was 2.48±0.3 (3σ), 15% above the calculated value. About 97% of measured points had less than 20% calculation-measurement difference and about 80% had less than 10%. The power peaking factor determined by this method consolidates also the calculations models.
Energy Technology Data Exchange (ETDEWEB)
Meireles, Ramiro Conceicao
2016-07-01
The shielding calculation methodology for radiotherapy services adopted in Brazil and in several countries is that described in publication 151 of the National Council on Radiation Protection and Measurements (NCRP 151). This methodology however, markedly employs several approaches that can impact both in the construction cost and in the radiological safety of the facility. Although this methodology is currently well established by the high level of use, some parameters employed in the calculation methodology did not undergo to a detailed assessment to evaluate the impact of the various approaches considered. In this work the MCNP5 Monte Carlo code was used with the purpose of evaluating the above mentioned approaches. TVLs values were obtained for photons in conventional concrete (2.35g / cm{sup 3}), considering the energies of 6, 10 and 25 MeV, respectively, first considering an isotropic radiation source impinging perpendicular to the barriers, and subsequently a lead head shielding emitting a shaped beam, in the format of a pyramid trunk. Primary barriers safety margins, taking in account the head shielding emitting photon beam pyramid-shaped in the energies of 6, 10, 15 and 18 MeV were assessed. A study was conducted considering the attenuation provided by the patient's body in the energies of 6,10, 15 and 18 MeV, leading to new attenuation factors. Experimental measurements were performed in a real radiotherapy room, in order to map the leakage radiation emitted by the accelerator head shielding and the results obtained were employed in the Monte Carlo simulation, as well as to validate the entire study. The study results indicate that the TVLs values provided by (NCRP, 2005) show discrepancies in comparison with the values obtained by simulation and that there may be some barriers that are calculated with insufficient thickness. Furthermore, the simulation results show that the additional safety margins considered when calculating the width of the
Score Calculation in Informatics Contests Using Multiple Criteria Decision Methods
Jurate SKUPIENE
2011-01-01
The Lithuanian Informatics Olympiad is a problem solving contest for high school students. The work of each contestant is evaluated in terms of several criteria, where each criterion is measured according to its own scale (but the same scale for each contestant). Several jury members are involved in the evaluation. This paper analyses the problem how to calculate the aggregated score for whole submission in the above mentioned situation. The chosen methodology for solving this problem is Mult...
Experiences with leak rate calculations methods for LBB application
Energy Technology Data Exchange (ETDEWEB)
Grebner, H.; Kastner, W.; Hoefler, A.; Maussner, G. [and others
1997-04-01
In this paper, three leak rate computer programs for the application of leak before break analysis are described and compared. The programs are compared to each other and to results of an HDR Reactor experiment and two real crack cases. The programs analyzed are PIPELEAK, FLORA, and PICEP. Generally, the different leak rate models are in agreement. To obtain reasonable agreement between measured and calculated leak rates, it was necessary to also use data from detailed crack investigations.
Energy Technology Data Exchange (ETDEWEB)
Cheng-Yang Tan
2001-07-30
We will show in this paper a method for calculating the longitudinal phase space distribution when the time profile of the bunch as measured by a wall current monitor is given. The key to this method is the assumption that the bunch is matched to the bucket. With this assumption, we will show that the method boils down to solving a simple upper triangular matrix equation. We will also illustrate the method with two examples and show the method's shortcomings.
Sørensen, R.; Zinko, U.; Seibert, J.
2005-01-01
The topographic wetness index (TWI, ln(a/tanβ)), which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correlation with the following measured variables: vascular plant species richness, soil pH, groundwa...
Analytical method for calculation of navigational data for the position of a satellite
Lala, P.
1975-01-01
A method is described for calculating the position of a satellite at the instants when measurements are made on board. The initial conditions used were the mean orbital elements of the satellite and their time derivatives in one orbit. The results of the calculation are compared with those obtained by numerical integration, and it is found that results are identical at the beginning of an orbit, but change as the orbit progresses. The advantages and disadvantages of the analytical method are presented.
Sensitivity measures in probabilistic methods
International Nuclear Information System (INIS)
The probabilistic methods used in Structural Reliability studies are aimed at I assessing failure probabilities or variable distributions as a function of the input random variables of a model. To quantify the impact of input uncertainties, two main sensitivity study methods, implemented in the PROBAN software structural are available. One measures the sensitivity of ''target'' values to input parameters, whilst the other, which is a typical reliability tool, assesses the stochastic importance of the input variables. These sensitivity measures reveal the impact of change on parameter values. Importance measures are used to restrict the number of initial random variables, thereby improving concentration on major uncertainties. This paper describes the two techniques using methodological examples and presents their main advantages. (author). 13 refs., 13 figs., 8 tabs., 3 appends
The application of advanced rotor (performance) methods for design calculations
Energy Technology Data Exchange (ETDEWEB)
Bussel, G.J.W. van [Delft Univ. of Technology, Inst. for Wind Energy, Delft (Netherlands)
1997-08-01
The calculation of loads and performance of wind turbine rotors has been a topic for research over the last century. The principles for the calculation of loads on rotor blades with a given specific geometry, as well as the development of optimal shaped rotor blades have been published in the decades that significant aircraft development took place. Nowadays advanced computer codes are used for specific problems regarding modern aircraft, and application to wind turbine rotors has also been performed occasionally. The engineers designing rotor blades for wind turbines still use methods based upon global principles developed in the beginning of the century. The question what to expect in terms of the type of methods to be applied in a design environment for the near future is addressed here. (EG) 14 refs.
Implicit calculations of transonic flows using monotone methods
Goorjian, P. M.; van Buskirk, R.
1981-01-01
Implicit approximate-factorization algorithms have been developed that use monotone methods for the calculation of steady and unsteady transonic flows governed by the small-disturbance-potential equation. These algorithms use the new Engquist-Osher switch in the type-dependent differencing in place of the standard Murman-Cole switch. The resulting algorithms are more stable; hence, calculations can be done more efficiently. For steady flows, the convergence rate is about 35% faster, and for unsteady flows the allowable time step is about 10 times larger. These improvements are achieved with no increase in computer storage and with only minor modifications in codes that use the Murman-Cole switch. Also an implicit algorithm has been developed for the steady full-potential equation in one-dimension, which uses monotone methods.
Methods and computer codes for nuclear systems calculations
Indian Academy of Sciences (India)
B P Kochurov; A P Knyazev; A Yu Kwaretzkheli
2007-02-01
Some numerical methods for reactor cell, sub-critical systems and 3D models of nuclear reactors are presented. The methods are developed for steady states and space–time calculations. Computer code TRIFON solves space-energy problem in (, ) systems of finite height and calculates heterogeneous few-group matrix parameters of reactor cells. These parameters are used as input data in the computer code SHERHAN solving the 3D heterogeneous reactor equation for steady states and 3D space–time neutron processes simulation. Modification of TRIFON was developed for the simulation of space–time processes in sub-critical systems with external sources. An option of SHERHAN code for the system with external sources is under development.
Problems in radiation shielding calculations with Monte Carlo methods
International Nuclear Information System (INIS)
The Monte Carlo method is a very useful tool for solving a large class of radiation transport problem. In contrast with deterministic method, geometric complexity is a much less significant problem for Monte Carlo calculations. However, the accuracy of Monte Carlo calculations is of course, limited by statistical error of the quantities to be estimated. In this report, we point out some typical problems to solve a large shielding system including radiation streaming. The Monte Carlo coupling technique was developed to settle such a shielding problem accurately. However, the variance of the Monte Carlo results using the coupling technique of which detectors were located outside the radiation streaming, was still not enough. So as to bring on more accurate results for the detectors located outside the streaming and also for a multi-legged-duct streaming problem, a practicable way of ''Prism Scattering technique'' is proposed in the study. (author)
Helicity methods in LO and NLO QCD calculations
International Nuclear Information System (INIS)
The goal of this thesis is the acceleration of numerical calculations of QCD observables, both at leading order and next-to-leading order in the coupling constant. In particular, the optimization of helicity and spin summation in the context of VEGAS Monte Carlo algorithms is investigated. In the literature, two such methods are mentioned but without detailed analyses. Only one of these methods can be used at next-to-leading order. This work presents a total of five different methods that replace the helicity sums with a Monte Carlo integration. This integration can be combined with the existing phase space integral, in the hope that this causes less overhead than the complete summation. For three of these methods, an extension to existing subtraction terms is developed which is required to enable next-to-leading order calculations. All methods are analyzed with respect to efficiency, accuracy, and ease of implementation before they are compared with each other. In this process, one method shows clear advantages in relation to all others.
Directory of Open Access Journals (Sweden)
R. Sørensen
2006-01-01
Full Text Available The topographic wetness index (TWI, ln(a/tanβ, which combines local upslope contributing area and slope, is commonly used to quantify topographic control on hydrological processes. Methods of computing this index differ primarily in the way the upslope contributing area is calculated. In this study we compared a number of calculation methods for TWI and evaluated them in terms of their correlation with the following measured variables: vascular plant species richness, soil pH, groundwater level, soil moisture, and a constructed wetness degree. The TWI was calculated by varying six parameters affecting the distribution of accumulated area among downslope cells and by varying the way the slope was calculated. All possible combinations of these parameters were calculated for two separate boreal forest sites in northern Sweden. We did not find a calculation method that performed best for all measured variables; rather the best methods seemed to be variable and site specific. However, we were able to identify some general characteristics of the best methods for different groups of measured variables. The results provide guiding principles for choosing the best method for estimating species richness, soil pH, groundwater level, and soil moisture by the TWI derived from digital elevation models.
International Nuclear Information System (INIS)
A new code was developed that calculates the spectrum, the state and the degree of polarization of the radiation emitted by any insertion device. It integrates along an arbitrary electron trajectory without any approximations. The trajectory can be derived either from a model undulator including random field errors or from a measured field distribution from a real undulator. The calculated one-electron pattern is convoluted with the electron beam emittance. Spectral calculations for the crossed field undulator U-2 at BESSY employing measured magnetic field data agree with absolute measurements of the spectra. (author) 18 refs.; 1 fig
Testing the QA Method for Calculating Jet v_{2}
Mueller, Jason
2014-01-01
For the summer, I was assigned to work on the ALICE experiment with Alice Ohlson. I wrote several programs throughout the summer that were used to calculate jet v 2 using a non-standard method described by my supervisor in her Ph.D. thesis. Though the project is not yet complete, significant progress has been made, and the results so far seem promising.
Calculations of pair production by Monte Carlo methods
International Nuclear Information System (INIS)
We describe some of the technical design issues associated with the production of particle-antiparticle pairs in very large accelerators. To answer these questions requires extensive calculation of Feynman diagrams, in effect multi-dimensional integrals, which we evaluate by Monte Carlo methods on a variety of supercomputers. We present some portable algorithms for generating random numbers on vector and parallel architecture machines. 12 refs., 14 figs
Calculations of pair production by Monte Carlo methods
Energy Technology Data Exchange (ETDEWEB)
Bottcher, C.; Strayer, M.R.
1991-01-01
We describe some of the technical design issues associated with the production of particle-antiparticle pairs in very large accelerators. To answer these questions requires extensive calculation of Feynman diagrams, in effect multi-dimensional integrals, which we evaluate by Monte Carlo methods on a variety of supercomputers. We present some portable algorithms for generating random numbers on vector and parallel architecture machines. 12 refs., 14 figs.
The New Performance Calculation Method of Fouled Axial Flow Compressor
Huadong Yang; Hong Xu
2014-01-01
Fouling is the most important performance degradation factor, so it is necessary to accurately predict the effect of fouling on engine performance. In the previous research, it is very difficult to accurately model the fouled axial flow compressor. This paper develops a new performance calculation method of fouled multistage axial flow compressor based on experiment result and operating data. For multistage compressor, the whole compressor is decomposed into two sections. The first section in...
Pulse measurement apparatus and method
Marciante, John R.; Donaldson, William R.; Roides, Richard G.
2011-10-25
An embodiment of the invention is directed to a pulse measuring system that measures a characteristic of an input pulse under test, particularly the pulse shape of a single-shot, nano-second duration, high shape-contrast optical or electrical pulse. An exemplary system includes a multi-stage, passive pulse replicator, wherein each successive stage introduces a fixed time delay to the input pulse under test, a repetitively-gated electronic sampling apparatus that acquires the pulse train including an entire waveform of each replica pulse, a processor that temporally aligns the replicated pulses, and an averager that temporally averages the replicated pulses to generate the pulse shape of the pulse under test. An embodiment of the invention is directed to a method for measuring an optical or an electrical pulse shape. The method includes the steps of passively replicating the pulse under test with a known time delay, temporally stacking the pulses, and temporally averaging the stacked pulses. An embodiment of the invention is directed to a method for increasing the dynamic range of a pulse measurement by a repetitively-gated electronic sampling device having a rated dynamic range capability, beyond the rated dynamic range of the sampling device; e.g., enhancing the dynamic range of an oscilloscope. The embodied technique can improve the SNR from about 300:1 to 1000:1. A dynamic range enhancement of four to seven bits may be achieved.
Hagedorn, Linda Serra
1998-01-01
A study explored two distinct methods of calculating a precise measure of gender-based wage differentials among college faculty. The first estimation considered wage differences using a formula based on human capital; the second included compensation for past discriminatory practices. Both measures were used to predict three specific aspects of…
Fast Stiffness Matrix Calculation for Nonlinear Finite Element Method
Directory of Open Access Journals (Sweden)
Emir Gülümser
2014-01-01
Full Text Available We propose a fast stiffness matrix calculation technique for nonlinear finite element method (FEM. Nonlinear stiffness matrices are constructed using Green-Lagrange strains, which are derived from infinitesimal strains by adding the nonlinear terms discarded from small deformations. We implemented a linear and a nonlinear finite element method with the same material properties to examine the differences between them. We verified our nonlinear formulation with different applications and achieved considerable speedups in solving the system of equations using our nonlinear FEM compared to a state-of-the-art nonlinear FEM.
Methods for calculating conjugate problems of heat transfer
Kalinin, E. K.; Dreitser, G. A.; Kostiuk, V. V.; Berlin, I. I.
Methods are examined for calculating various conjugate problems of heat transfer in channels and closed vessels in cases of single-phase and two-phase flow in steady and unsteady conditions. The single-phase-flow studies involve the investigation of gaseous and liquid heat-carriers in pipes, annular and plane channels, and pipe bundles in cases of cooling and heating. General relationships are presented for heat transfer in cases of film, transition, and nucleate boiling, as well as for boiling crises. Attention is given to methods for analyzing the filling and cooling of conduits and tanks by cryogenic liquids; and ways to intensify heat transfer in these conditions are examined.
Laub, Wolfram U.; Bakai, Annemarie; Nüsslin, Fridtjof
2001-06-01
The present study investigates the application of compensators for the intensity modulated irradiation of a thorax phantom. Measurements are compared with Monte Carlo and standard pencil beam algorithm dose calculations. Compensators were manufactured to produce the intensity profiles that were generated from the scientific version of the KonRad IMRT treatment-planning system for a given treatment plan. The comparison of dose distributions calculated with a pencil beam algorithm, with the Monte Carlo code EGS4 and with measurements is presented. By measurements in a water phantom it is demonstrated that the method used to manufacture the compensators reproduces the intensity profiles in a suitable manner. Monte Carlo simulations in a water phantom show that the accelerator head model used for simulations is sufficient. No significant overestimations of dose values inside the target volume by the pencil beam algorithm are found in the thorax phantom. An overestimation of dose values in lung by the pencil beam algorithm is also not found. Expected dose calculation errors of the pencil beam algorithm are suppressed, because the dose to the low density region lung is reduced by the use of a non-coplanar beam arrangement and by intensity modulation.
Unfolding method for first-principles LCAO electronic structure calculations
Lee, Chi-Cheng; Yamada-Takamura, Yukiko; Ozaki, Taisuke
2013-08-01
Unfolding the band structure of a supercell to a normal cell enables us to investigate how symmetry breakers such as surfaces and impurities perturb the band structure of the normal cell. We generalize the unfolding method, originally developed based on Wannier functions, to the linear combination of atomic orbitals (LCAO) method, and present a general formula to calculate the unfolded spectral weight. The LCAO basis set is ideal for the unfolding method because the basis functions allocated to each atomic species are invariant regardless of the existence of surface and impurity. The unfolded spectral weight is well defined by the property of the LCAO basis functions. In exchange for the property, the non-orthogonality of the LCAO basis functions has to be taken into account. We show how the non-orthogonality can be properly incorporated in the general formula. As an illustration of the method, we calculate the dispersive quantized spectral weight of a ZrB2 slab and show strong spectral broadening in the out-of-plane direction, demonstrating the usefulness of the unfolding method.
Unfolding method for first-principles LCAO electronic structure calculations
International Nuclear Information System (INIS)
Unfolding the band structure of a supercell to a normal cell enables us to investigate how symmetry breakers such as surfaces and impurities perturb the band structure of the normal cell. We generalize the unfolding method, originally developed based on Wannier functions, to the linear combination of atomic orbitals (LCAO) method, and present a general formula to calculate the unfolded spectral weight. The LCAO basis set is ideal for the unfolding method because the basis functions allocated to each atomic species are invariant regardless of the existence of surface and impurity. The unfolded spectral weight is well defined by the property of the LCAO basis functions. In exchange for the property, the non-orthogonality of the LCAO basis functions has to be taken into account. We show how the non-orthogonality can be properly incorporated in the general formula. As an illustration of the method, we calculate the dispersive quantized spectral weight of a ZrB2 slab and show strong spectral broadening in the out-of-plane direction, demonstrating the usefulness of the unfolding method. (paper)
Comparison of dose calculation methods for brachytherapy of intraocular tumors
Energy Technology Data Exchange (ETDEWEB)
Rivard, Mark J.; Chiu-Tsao, Sou-Tung; Finger, Paul T.; Meigooni, Ali S.; Melhus, Christopher S.; Mourtada, Firas; Napolitano, Mary E.; Rogers, D. W. O.; Thomson, Rowan M.; Nath, Ravinder [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States); Quality MediPhys LLC, Denville, New Jersey 07834 (United States); New York Eye Cancer Center, New York, New York 10065 (United States); Department of Radiation Oncology, Comprehensive Cancer Center of Nevada, Las Vegas, Nevada 89169 (United States); Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States); Department of Radiation Physics, University of Texas, M.D. Anderson Cancer Center, Houston, Texas 77030 (United States) and Department of Experimental Diagnostic Imaging, University of Texas, M.D. Anderson Cancer Center, Houston, Texas 77030 (United States); Physics, Elekta Inc., Norcross, Georgia 30092 (United States); Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut 06520 (United States)
2011-01-15
Purpose: To investigate dosimetric differences among several clinical treatment planning systems (TPS) and Monte Carlo (MC) codes for brachytherapy of intraocular tumors using {sup 125}I or {sup 103}Pd plaques, and to evaluate the impact on the prescription dose of the adoption of MC codes and certain versions of a TPS (Plaque Simulator with optional modules). Methods: Three clinical brachytherapy TPS capable of intraocular brachytherapy treatment planning and two MC codes were compared. The TPS investigated were Pinnacle v8.0dp1, BrachyVision v8.1, and Plaque Simulator v5.3.9, all of which use the AAPM TG-43 formalism in water. The Plaque Simulator software can also handle some correction factors from MC simulations. The MC codes used are MCNP5 v1.40 and BrachyDose/EGSnrc. Using these TPS and MC codes, three types of calculations were performed: homogeneous medium with point sources (for the TPS only, using the 1D TG-43 dose calculation formalism); homogeneous medium with line sources (TPS with 2D TG-43 dose calculation formalism and MC codes); and plaque heterogeneity-corrected line sources (Plaque Simulator with modified 2D TG-43 dose calculation formalism and MC codes). Comparisons were made of doses calculated at points-of-interest on the plaque central-axis and at off-axis points of clinical interest within a standardized model of the right eye. Results: For the homogeneous water medium case, agreement was within {approx}2% for the point- and line-source models when comparing between TPS and between TPS and MC codes, respectively. For the heterogeneous medium case, dose differences (as calculated using the MC codes and Plaque Simulator) differ by up to 37% on the central-axis in comparison to the homogeneous water calculations. A prescription dose of 85 Gy at 5 mm depth based on calculations in a homogeneous medium delivers 76 Gy and 67 Gy for specific {sup 125}I and {sup 103}Pd sources, respectively, when accounting for COMS-plaque heterogeneities. For off
Solar Opacity Calculations Using the Super-transition-array Method
Krief, M.; Feigel, A.; Gazit, D.
2016-04-01
A new opacity model has been developed based on the Super-Transition-Array (STA) method for the calculation of monochromatic opacities of plasmas in local thermodynamic equilibrium. The atomic code, named STAR (STA-Revised), is described and used to calculate spectral opacities for a solar model implementing the recent AGSS09 composition. Calculations are carried out throughout the solar radiative zone. The relative contributions of different chemical elements and atomic processes to the total Rosseland mean opacity are analyzed in detail. Monochromatic opacities and charge-state distributions are compared with the widely used Opacity Project (OP) code, for several elements near the radiation–convection interface. STAR Rosseland opacities for the solar mixture show a very good agreement with OP and the OPAL opacity code throughout the radiation zone. Finally, an explicit STA calculation was performed of the full AGSS09 photospheric mixture, including all heavy metals. It was shown that, due to their extremely low abundance, and despite being very good photon absorbers, the heavy elements do not affect the Rosseland opacity.
Comparison of organ dosimetry methods and effective dose calculation methods for paediatric CT
International Nuclear Information System (INIS)
Computed tomography (CT) is the single biggest ionising radiation risk from anthropogenic exposure. Reducing unnecessary carcinogenic risks from this source requires the determination of organ and tissue absorbed doses to estimate detrimental stochastic effects. In addition, effective dose can be used to assess comparative risk between exposure situations and facilitate dose reduction through optimisation. Children are at the highest risk from radiation induced carcinogenesis and therefore dosimetry for paediatric CT recipients is essential in addressing the ionising radiation health risks of CT scanning. However, there is no well-defined method in the clinical environment for routinely and reliably performing paediatric CT organ dosimetry and there are numerous methods utilised for estimating paediatric CT effective dose. Therefore, in this study, eleven computational methods for organ dosimetry and/or effective dose calculation were investigated and compared with absorbed doses measured using thermoluminescent dosemeters placed in a physical anthropomorphic phantom representing a 10 year old child. Three common clinical paediatric CT protocols including brain, chest and abdomen/pelvis examinations were evaluated. Overall, computed absorbed doses to organs and tissues fully and directly irradiated demonstrated better agreement (within approximately 50 %) with the measured absorbed doses than absorbed doses to distributed organs or to those located on the periphery of the scan volume, which showed up to a 15-fold dose variation. The disparities predominantly arose from differences in the phantoms used. While the ability to estimate CT dose is essential for risk assessment and radiation protection, identifying a simple, practical dosimetry method remains challenging.
Pion dose distribution calculations and measurements for dynamic radiotherapy
International Nuclear Information System (INIS)
Routine three dimensional conformation therapy with negative pions is done with the PIOTRON at SIN since two years. More than 60 patients have been treated by spot scan with the 60 converging beams for deep seated tumors in the pelvic region. Extensive measurements have been performed on various phantoms, homogeneous and anthropomorphic, to investigate the influence of tissue inhomogeneities and verify treatment planning calculations. Total dose has been measured by T.E. ionization chambers and TLD, two dimensional stop distributions exposed in planes between phantom slices. In vivo measurements with ionization chambers, as well as catheters filled with /sup 7/LiF TLD's and rolled Al foils, introduced in bladder or rectum, have been used to confirm dose distributions in patients. To check predictions of differences of RBE due to variations in treatment volumes or beam configuration, treatment plans, reflecting typical situation in therapy, have been created for radiobiological investigations. Various user groups have measured biological effects by cell survival experiments with mammalian cells or with mouse intestinal crypt cell assay
Investigations on the Migration Mode Method (MMM) for reactor calculations
International Nuclear Information System (INIS)
Current calculation codes for reactor analysis are based on the multi-group method to evaluate energy distribution of neutron flux. Usually a two energy group diffusion equation is adopted. This choice is adequate for PWRs associated to cross sections libraries tabulated versus fuel exposure and other state parameters as moderator density, fuel temperature, boron concentration. An improvement of this approach is represented by the Migration Mode Method (MMM) by which the neutron spectrum is expanded in terms of base functions corresponding to the different modes of migration of the neutrons in the energy dimension. For a thermal reactor, three such functions may be easily identified: the Maxwellian distribution of the neutrons at thermal equilibrium with the moderator, the 1/E slowing down distribution (corrected to take into account resonance absorption effects) and the fission neutron spectrum. The (space-dependent) coefficients of the expansion are calculated by solving a differential equation which results having a structure similar to the one relevant to multi-group theory. The method can therefore be easily implemented adopting existing diffusion theory codes. With the present work, some investigations on the MMM are described relevant to UO2 fuelled PWR systems. Demonstrative results are given to validate the potentiality of the method. (authors)
Investigations on the migration mode method (MMM) for reactor calculations
International Nuclear Information System (INIS)
Current calculation codes for reactor analysis are based on the multi-group method to evaluate energy distribution of neutron flux. Usually a two energy group diffusion equation is adopted. This choice is adequate for PWRs associated to cross sections libraries tabulated versus fuel exposure and other state parameters as moderator density, fuel temperature, boron concentration. An improvement of this approach is represented by the migration mode method (MMM) by which the neutron spectrum is expanded in terms of base functions corresponding to the different modes of migration of the neutrons in the energy dimension. For a thermal reactor, three such functions may be easily identified: the Maxwellian distribution of the neutrons at thermal equilibrium with the moderator, the 1/E slowing down distribution (corrected to take into account resonance absorption effects) and the fission neutron spectrum. The (space-dependent) coefficients of the expansion are calculated by solving a differential equation which results having a structure similar to the one relevant to multi-group theory. The method can therefore be easily implemented adopting existing diffusion theory codes. With the present work, some investigations on the MMM are described relevant to UO2 fuelled PWR systems. Demonstrative results are given to validate the potentiality of the method
The new performance calculation method of fouled axial flow compressor.
Yang, Huadong; Xu, Hong
2014-01-01
Fouling is the most important performance degradation factor, so it is necessary to accurately predict the effect of fouling on engine performance. In the previous research, it is very difficult to accurately model the fouled axial flow compressor. This paper develops a new performance calculation method of fouled multistage axial flow compressor based on experiment result and operating data. For multistage compressor, the whole compressor is decomposed into two sections. The first section includes the first 50% stages which reflect the fouling level, and the second section includes the last 50% stages which are viewed as the clean stage because of less deposits. In this model, the performance of the first section is obtained by combining scaling law method and linear progression model with traditional stage stacking method; simultaneously ambient conditions and engine configurations are considered. On the other hand, the performance of the second section is calculated by averaged infinitesimal stage method which is based on Reynolds' law of similarity. Finally, the model is successfully applied to predict the 8-stage axial flow compressor and 16-stage LM2500-30 compressor. The change of thermodynamic parameters such as pressure ratio, efficiency with the operating time, and stage number is analyzed in detail. PMID:25197717
The New Performance Calculation Method of Fouled Axial Flow Compressor
Directory of Open Access Journals (Sweden)
Huadong Yang
2014-01-01
Full Text Available Fouling is the most important performance degradation factor, so it is necessary to accurately predict the effect of fouling on engine performance. In the previous research, it is very difficult to accurately model the fouled axial flow compressor. This paper develops a new performance calculation method of fouled multistage axial flow compressor based on experiment result and operating data. For multistage compressor, the whole compressor is decomposed into two sections. The first section includes the first 50% stages which reflect the fouling level, and the second section includes the last 50% stages which are viewed as the clean stage because of less deposits. In this model, the performance of the first section is obtained by combining scaling law method and linear progression model with traditional stage stacking method; simultaneously ambient conditions and engine configurations are considered. On the other hand, the performance of the second section is calculated by averaged infinitesimal stage method which is based on Reynolds’ law of similarity. Finally, the model is successfully applied to predict the 8-stage axial flow compressor and 16-stage LM2500-30 compressor. The change of thermodynamic parameters such as pressure ratio, efficiency with the operating time, and stage number is analyzed in detail.
Investigations on the migration mode method (MMM) for reactor calculations
Energy Technology Data Exchange (ETDEWEB)
Dall' Osso, Aldo [AREVA NP, Tour Areva, 92084 Paris La Defense Cedex (France); Gandini, Augusto [DINCE, University of Rome ' La Sapienza' , Piazzale Aldo Moro 5, 00185 Rome (Italy)], E-mail: augusto.gandini@uniroma1.it; Rotella, Rossella [S.R.S. GROUP S.r.l., Via dei Prefetti 26, 00186 Rome (Italy)
2008-07-15
Current calculation codes for reactor analysis are based on the multi-group method to evaluate energy distribution of neutron flux. Usually a two energy group diffusion equation is adopted. This choice is adequate for PWRs associated to cross sections libraries tabulated versus fuel exposure and other state parameters as moderator density, fuel temperature, boron concentration. An improvement of this approach is represented by the migration mode method (MMM) by which the neutron spectrum is expanded in terms of base functions corresponding to the different modes of migration of the neutrons in the energy dimension. For a thermal reactor, three such functions may be easily identified: the Maxwellian distribution of the neutrons at thermal equilibrium with the moderator, the 1/E slowing down distribution (corrected to take into account resonance absorption effects) and the fission neutron spectrum. The (space-dependent) coefficients of the expansion are calculated by solving a differential equation which results having a structure similar to the one relevant to multi-group theory. The method can therefore be easily implemented adopting existing diffusion theory codes. With the present work, some investigations on the MMM are described relevant to UO{sub 2} fuelled PWR systems. Demonstrative results are given to validate the potentiality of the method.
Convergence and accuracy of numerical methods for trajectory calculations
International Nuclear Information System (INIS)
Computation of trajectories by a kinematic method requires the numerical solution of the differential equation by which the trajectory is defined. A widely used method is the iterative scheme of Petterssen which has second-order accuracy. The convergence and accuracy of this scheme is investigated for some simple flow types where analytical solutions are available. The results are discussed in comparison to other methods, especially a method similar to the Patterssen scheme, which has been recommended for use in semi-Lagrangian advection schemes. The truncation error in trajectory calculations should be kept about one order of magnitude smaller than the total uncertainty, which is mainly due to analysis errors and limited resolution of the wind data. It is shown that for trajectory calculations based on the typical output of current numerical weather prediction models or comparable data, this requires a time step 15% of the time step necessary to achieve convergence. If a fixed time step is used, it should not exceed about 0.5 h. Flexible time steps, based on the estimate of the truncation error which is provided by the difference between the first and the second iteration, are an attractive alternative. 26 refs., 8 figs
Calculation of VPP basing on functional analyzing method
Institute of Scientific and Technical Information of China (English)
Bai Kaixiang; Wang Dexun; Han Jiurui
2007-01-01
The establishment and realization of the VPP calucation's model for the functional analytic theory are discussed in this paper. Functional analyzing method is a theoretical model of the VPP calculation which can eliminate the influence of the sail and board's size skillfully, so it can be regarded as a brief standard of the sailboard's VPP results. As a brief watery dynamical model, resistance on board can be regarded as a direct proportion to the square of the boat-velocity. The boat-velocities at the state of six wind-velocities (3 m/s-8 m/s) with angles of 25°-180° are obtained by calculating, which provides an important gist of the sailing-route's selection in upwind-sailing.
Calculation method of solar radiation incident upon slopes considering topography
International Nuclear Information System (INIS)
When radiation in a basin is calculated, slope inclination, slope orientation and topography of surroundings have to be taken into account. The method of approximation to topography by triangles proposed by Miura et al. is employed to take slope characteristics and topography of surroundings into account. Authors prepared 360 directions' shades altitudes, i.e. every degree of angle, for each triangle in advance, and used these shades' altitudes to calculate both direct radiation on a slope diffuse radiation taking topography of surroundings into account. And authors show how to estimate hourly direct and diffuse solar radiation from hourly horizontal global radiation and synthesize hourly slope global radiation on slopes
International Nuclear Information System (INIS)
Background: The on-line low-level liquid radioactivity concentration measurement device is designed for monitoring the radioactivity level of nuclear power plant waste water. The relation between the radioactivity concentration of 137Cs in the liquid of pipeline and the counting rate of measurement device, i.e. the response coefficient is must be known. It is generally given by experimental calibration. But the calibration is difficult for on-line measurement. Purpose: This paper attempts to study the response coefficient of on-line measurement device by calculation. Methods: The response coefficient is calculated by Monte Carlo method and in which gamma-ray transport processes in detection device are simulated. The response counts in Nal detector derived from 137Cs in the liquid are calculated. Results: The response coefficient of off-line measuring device is calculated firstly. The result is in good agreement with the experimental calibration and the difference is small than 3%. It is indicated that the method is correct and the calculation model is reasonable. Then, the response coefficient of on-line measuring devices is calculated according to the on-line measurement device design and the structure of Nal detector. The minimum detectable concentration is given according to the response coefficient and the background count rate. Conclusions: The response coefficient of on-line measurement device is 1.249×10-4 s-1·Bq-1·m3 and the minimum detectable concentration can reach (4-5)×103 Bq·m-3 when the thickness of lead shield is 80 mm. (authors)
A unique manual method for emergency offsite dose calculations
International Nuclear Information System (INIS)
This paper describes a manual method developed for performance of emergency offsite dose calculations for PP and L's Susquehanna Steam Electric Station. The method is based on a three-part carbonless form. The front page guides the user through selection of the appropriate accident case and inclusion of meteorological and effluent data data. By circling the applicable accident descriptors, the user circles the dose factors on pages 2 and 3 which are then simply multiplied to yield the whole body and thyroid dose rates at the plant boundary, two, five, and ten miles. The process used to generate the worksheet is discussed, including the method used to incorporate the observed terrain effects on airflow patterns caused by the Susquehanna River Valley topography
Nested element method in multidimensional neutron diffusion calculations
International Nuclear Information System (INIS)
A new numerical method is developed that is particularly efficient in solving the multidimensional neutron diffusion equation in geometrically complex systems. The needs for a generally applicable and fast running computer code have stimulated, here presented, the inroad of a nonclassical (R-function) numerical method into the nuclear field. By using the R-functions, the geometrical components of the diffusion problem are a priory analytically implemented into the approximate solution. The class of functions, to which the approximate solution belongs, is chosen as close to the exact solution class as practically acceptable from the time consumption point of view. That implies a drastic reduction of the number of degrees of freedom, compared to the other methods. Furthermore, the reduced number of degrees of freedom enables calculation of large multidimensional problems on small computers
Nested element method in multidimensional neutron diffusion calculations
International Nuclear Information System (INIS)
A new numerical method is developed that is particularly efficient in solving the multidimensional neutron diffusion equation in geometrically complex systems. The needs for a generally applicable and fast running computer code have stimulated the inroad of a nonclassical (R-function) numerical method into the nuclear field. By using the R-functions, the geometrical components of the diffusion problem are a priori analytically implemented into the approximate solution. The class of functions, to which the approximate solution belongs, is chosen as close to the exact solution class as practically acceptable from the time consumption point of view. That implies a drastic reduction of the number of degrees of freedom, compared to the other methods. Furthermore, the reduced number of degrees of freedom enables calculation of large multidimensional problems on small computers
Large Scale Electronic Structure Calculations using Quantum Chemistry Methods
Scuseria, Gustavo E.
1998-03-01
This talk will address our recent efforts in developing fast, linear scaling electronic structure methods for large scale applications. Of special importance is our fast multipole method( M. C. Strain, G. E. Scuseria, and M. J. Frisch, Science 271), 51 (1996). (FMM) for achieving linear scaling for the quantum Coulomb problem (GvFMM), the traditional bottleneck in quantum chemistry calculations based on Gaussian orbitals. Fast quadratures(R. E. Stratmann, G. E. Scuseria, and M. J. Frisch, Chem. Phys. Lett. 257), 213 (1996). combined with methods that avoid the Hamiltonian diagonalization( J. M. Millam and G. E. Scuseria, J. Chem. Phys. 106), 5569 (1997) have resulted in density functional theory (DFT) programs that can be applied to systems containing many hundreds of atoms and ---depending on computational resources or level of theory-- to many thousands of atoms.( A. D. Daniels, J. M. Millam and G. E. Scuseria, J. Chem. Phys. 107), 425 (1997). Three solutions for the diagonalization bottleneck will be analyzed and compared: a conjugate gradient density matrix search (CGDMS), a Hamiltonian polynomial expansion of the density matrix, and a pseudo-diagonalization method. Besides DFT, our near-field exchange method( J. C. Burant, G. E. Scuseria, and M. J. Frisch, J. Chem. Phys. 105), 8969 (1996). for linear scaling Hartree-Fock calculations will be discussed. Based on these improved capabilities, we have also developed programs to obtain vibrational frequencies (via analytic energy second derivatives) and excitation energies (through time-dependent DFT) of large molecules like porphyn or C_70. Our GvFMM has been extended to periodic systems( K. N. Kudin and G. E. Scuseria, Chem. Phys. Lett., in press.) and progress towards a Gaussian-based DFT and HF program for polymers and solids will be reported. Last, we will discuss our progress on a Laplace-transformed \\cal O(N^2) second-order pertubation theory (MP2) method.
Measurements and calculations of doses from radioactive particles
International Nuclear Information System (INIS)
Three Mile Island (TMI) and Tchernobyl reactor accidents have revealed the importance of the skin exposure to beta radiation produced by small high activity sources, named 'hot particles'. In nuclear power reactors, they may arise as small fragments of irradiated fuel or material which have been neutron activated by passing through the reactor co. In recent years, skin exposure to hot particles has been subject to different limitation criteria, formulated by AIEA, ICRP, NCRP working groups. The present work is the contribution of CEA Grenoble to a contract of the Commission of the European communities in cooperation with several laboratories: University of Birmingham, University of Toulouse and University of Montpellier with the main goal to check experiments and calculations of tissue dose from 60Co radioactive particles. This report is split up into two parts: hot particle dosimetry close to a 60Co spherical sample with an approximately 200 μm diameter, using a PTW extrapolation chamber model 233991; dose calculations from two codes: the Varskin Mod 2 computer code and the Hot 25 S2 Monte Carlo algorithm. The two codes lead to similar results; nevertheless there is a large discrepancy (of about 2) between calculations and PTW measurements which are higher by a factor of 1.9. At a 70 μm skin depth and for 1 cm2 irradiated area, the total (β + γ) tissue dose rate delivered by a spherical ( φ = 200 μm) 60Co source, in contact with skin, is of the order of 6.1 10-2 nGy s-1 Bq-1. (author)
Rodný, Marek; Nolz, Reinhard; Novák, Viliam; Hlaváčiková, Hana; Loiskandl, Willibald; Himmelbauer, Margarita
2016-04-01
The aim of this study was to present and validate an alternative evapotranspiration calculation procedure that includes specific expression for the aerodynamic resistance. Calculated daily potential evapotranspiration totals were compared to the results of FAO56 procedure application and to the results of measurements taken with a precision weighing lysimeter permanently grown with irrigated, short grass. For the examination period from March 17 through October 31, 2011, it was found that daily potential evapotranspiration estimates obtained by both calculation procedures fitted well to the lysimeter measurements. Potential evapotranspiration daily totals calculated with the use of the proposed aerodynamic resistance calculation procedure gave better results for days with higher evapotranspiration, compared to the FAO56 method. The most important is that the approach based on the proposed alternative aerodynamic resistance could be effectively used even for a wide variety of crops, because it is not limited to any particular crop.
Comparison of calculation and measurements of reaction rates in the outer regions of superphenix
International Nuclear Information System (INIS)
This paper brings together the results of two analyses of the Superphenix start-up measurements in the radial shield. Two different methods of calculation have been used based on SN transport theory (the PROPANE DO formulaire with the BISTRO code) and adjusted diffusion coefficients (the code SNAPSH using ADC method D). The PROPANE DO formulaire was found to give good agreement with the measured thermal flux both in the prediction of radial attenuation and in the reproduction of the axial profile. The ADC method was found to underestimate the attenuation. There were difficulties in reproducing the flux and neutron spectrum at the breeder/shield interface with both methods. This detailed comparison with measured values will assist in the formulation of recommended calculational routes for analysis of fast reactor shielding problems, an example of which has been the proposal of revised uncertainties for the PROPANE DO formulaire
Development of software for internal dose calculation from bioassay measurements
International Nuclear Information System (INIS)
Recently developed biokinetic models of ICRP permit increasingly realistic descriptions of the behaviour of radionuclides in the human body. This, however, has made the interpretation of bioassay data extremely difficult. Thus computer programs for implementing these models are in need, but very few are available. The present work describes personal-computer-based software, MONDAL2 (monitoring to dose calculation ver. 2), that enables users to estimate intake activity and the resulting effective doses from bioassay measurements for both workers and members of the public. This software runs on Microsoft Windows 95, 98, Millennium edition, 2000 or XP. If the system is to be fully copied to a hard disk, hard disk space of 23 MB is required. This software is distributed by the National Inst. of Radiological Sciences free of charge. (authors)
A CNS calculation line based on a Monte Carlo method
International Nuclear Information System (INIS)
Full text: The design of the moderator cell of a Cold Neutron Source (CNS) involves many different considerations regarding geometry, location, and materials. Decisions taken in this sense affect not only the neutron flux in the source neighborhood, which can be evaluated by a standard empirical method, but also the neutron flux values in experimental positions far away of the neutron source. At long distances from the neutron source, very time consuming 3D deterministic methods or Monte Carlo transport methods are necessary in order to get accurate figures. Standard and typical terminology such as average neutron flux, neutron current, angular flux, luminosity, are magnitudes very difficult to evaluate in positions located several meters away from the neutron source. The Monte Carlo method is a unique and powerful tool to transport neutrons. Its use in a bootstrap scheme appears to be an appropriate solution for this type of systems. The proper use of MCNP as the main tool leads to a fast and reliable method to perform calculations in a relatively short time with low statistical errors. The design goal is to evaluate the performance of the neutron sources, their beam tubes and neutron guides at specific experimental locations in the reactor hall as well as in the neutron or experimental hall. In this work, the calculation methodology used to design Cold, Thermal and Hot Neutron Sources and their associated Neutron Beam Transport Systems, based on the use of the MCNP code, is presented. This work also presents some changes made to the cross section libraries in order to cope with cryogenic moderators such as liquid hydrogen and liquid deuterium. (author)
Study on calculation methods for the effective delayed neutron fraction
International Nuclear Information System (INIS)
The effective delayed neutron fraction βeff is one of the important neutronic parameters from a view point of a reactor kinetics. Several Monte-Carlo-based methods to estimate βeff have been proposed to date. In order to quantify the accuracy of these methods, we study calculation methods for βeff by analyzing various fast neutron systems including the bare spherical systems (Godiva, Jezebel, Skidoo, Jezebel-240), the reflective spherical systems (Popsy, Topsy, Flattop-23), MASURCA-R2 and MASURCA-ZONA2, and FCA XIX-1, XIX-2 and XIX-3. These analyses are performed by using SLAROM-UF and CBG for the deterministic method and MVP-II for the Monte Carlo method. We calculate βeff with various definitions such as the fundamental value β0, the standard definition, Nauchi's definition and Meulekamp's definition, and compare these results with each other. Through the present study, we find the following: The largest difference among the standard definition of βeff , Nauchi's βeff and Meulekamp's βeff is approximately 10%. The fundamental value β0 is quite larger than the others in several cases. For all the cases, Meulekamp's βeff is always higher than Nauchi's βeff. This is because Nauchi's βeff considers the average neutron multiplicity value per fission which is large in the high energy range (1MeV-10MeV), while the definition of Meulekamp's βeff does not include this parameter. Furthermore, we evaluate the multi-generation effect on βeff values and demonstrate that this effect should be considered to obtain the standard definition values of βeff. (author)
Evaluation Measures and Methods: Some Intersections.
Elliott, John
The literature is reviewed for four combinations of evaluation measures and methods: traditional methods with traditional measures (T-Meth/T-Mea), nontraditional methods with traditional measures (N-Meth/T-Mea), traditional measures with nontraditional measures (T-Meth/N-Mea), and nontraditional methods with nontraditional measures (N-Meth/N-Mea).…
Ratio method of measuring W boson mass
Energy Technology Data Exchange (ETDEWEB)
Guo, Feng [Stony Brook Univ., NY (United States)
2010-08-01
This dissertation describes an alternative method of measuring the W boson mass in DØ experiment. Instead of extracting M_{W} from the fitting of W → ev fast Monte Carlo simulations to W → ev data as in the standard method, we make the direct fit of transverse mass between W → ev data and Z → ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (M_{W}/M_{Z}). Given the precisely measured Z boson mass, W mass is directly fitted from W → ev and Z → ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb^{-1} DØ Run IIa dataset, ratio method gives M_{W} = 80435 ± 43(stat) ± 26(sys) MeV.
Ratio method of measuring $w$ boson mass
Energy Technology Data Exchange (ETDEWEB)
Guo, Feng; /SUNY, Stony Brook
2010-08-01
This dissertation describes an alternative method of measuring the W boson mass in D0 experiment. Instead of extracting M{sub W} from the fitting of W {yields} e{nu} fast Monte Carlo simulations to W {yields} e{nu} data as in the standard method, we make the direct fit of transverse mass between W {yields} e{nu} data and Z {yields} ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (M{sub W}/M{sub Z}). Given the precisely measured Z boson mass, W mass is directly fitted from W {yields} e{nu} and Z {yields} ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb{sup -1} D0 Run IIa dataset, ratio method gives M{sub W} = 80435 {+-} 43(stat) {+-} 26(sys) MeV.
International Nuclear Information System (INIS)
Measurements made during cycle 1 operation of Commonwealth Edison Company's Zion Unit 2 pressurized water reactor core were used to validate the Electric Power Research Institute Advanced Recycle Methodology Program. In addition to the usual reaction rate and axial trace measurements for determining power distributions, gamma scan measurements were available to provide additional data to validate the calculated power shapes. The parallel occurrence of gamma scan measurements and standard nuclear instrumentation measurements provided a unique opportunity to intercompare the results of these measurement methods. The calculated X-Y gamma scan behavior supported the behavior of the calculated X-Y reaction rates. The measured X-Y gamma scans were found to be more accurate than the measured X-Y reaction rates, with the latter showing significant differences among some symmetrically located assemblies. For both types of measurement, however, the modeling of the asymmetrically loaded assembly located furthest in the core periphery produced the poorest results. The axial gamma scan calculation proved very accurate except at the inlet and outlet regions
An accurate δf method for neoclassical transport calculation
International Nuclear Information System (INIS)
A δf method, solving drift kinetic equation, for neoclassical transport calculation is presented in detail. It is demonstrated that valid results essentially rely on the correct evaluation of marker density g in weight calculation. A general and accurate weighting scheme is developed without using some assumed g in weight equation for advancing particle weights, unlike the previous schemes. This scheme employs an additional weight function to directly solve g from its kinetic equation using the idea of δf method. Therefore the severe constraint that the real marker distribution must be consistent with the initially assumed g during a simulation is relaxed. An improved like-particle collision scheme is presented. By performing compensation for momentum, energy and particle losses arising from numerical errors, the conservations of all the three quantities are greatly improved during collisions. Ion neoclassical transport due to self-collisions is examined under finite banana case as well as zero banana limit. A solution with zero particle and zero energy flux (in case of no temperature gradient) over whole poloidal section is obtained. With the improvement in both like-particle collision scheme and weighting scheme, the δf simulation shows a significantly upgraded performance for neoclassical transport study. (author)
An accurate {delta}f method for neoclassical transport calculation
Energy Technology Data Exchange (ETDEWEB)
Wang, W.X.; Nakajima, N.; Murakami, S.; Okamoto, M. [National Inst. for Fusion Science, Toki, Gifu (Japan)
1999-03-01
A {delta}f method, solving drift kinetic equation, for neoclassical transport calculation is presented in detail. It is demonstrated that valid results essentially rely on the correct evaluation of marker density g in weight calculation. A general and accurate weighting scheme is developed without using some assumed g in weight equation for advancing particle weights, unlike the previous schemes. This scheme employs an additional weight function to directly solve g from its kinetic equation using the idea of {delta}f method. Therefore the severe constraint that the real marker distribution must be consistent with the initially assumed g during a simulation is relaxed. An improved like-particle collision scheme is presented. By performing compensation for momentum, energy and particle losses arising from numerical errors, the conservations of all the three quantities are greatly improved during collisions. Ion neoclassical transport due to self-collisions is examined under finite banana case as well as zero banana limit. A solution with zero particle and zero energy flux (in case of no temperature gradient) over whole poloidal section is obtained. With the improvement in both like-particle collision scheme and weighting scheme, the {delta}f simulation shows a significantly upgraded performance for neoclassical transport study. (author)
International Nuclear Information System (INIS)
In order to confirm applicability and accuracy of FAC evaluation methods based on the coupled FAC model of static electrochemical analysis and dynamic oxide layer growth analysis, wall thinning rates calculated with the proposed methods were compared with those measured for the secondary piping of a PWR plant. Distributions of flow velocity and temperature along the whole system were calculated with 1D and 2D computational flow dynamics (CFD) codes and corrosive conditions were calculated with a N2H4-O2 reaction analysis code. Precise flow turbulence at major parts of the system was analyzed with 3D CFD codes to obtain mass transfer coefficients at structure surfaces. Then, wall thinning rates were calculated with the coupled FAC model by applying the mass transfer coefficients. Comparison of the calculated and measured results led to the following conclusions. 1) Structures with complicated geometry in the plant, e.g., the pair of a bend pipe and a valve, could be simplified as a combination of pipes for the calculation. 2) Flow distribution calculated with 3D CFD codes for a large-scale piping system could be extrapolated to those at the very surface of the piping to obtain a precise distribution of mass transfer coefficients at the region of interest. 3) Wall thinning rates calculated by applying the obtained mass transfer coefficients agreed with the measured rates within a factor of 2. 4) The effects of flow turbulence were transferred through a distance of more than 5 times the pipe diameter from the original turbulent point, but the effects on wall thinning rate were negligibly small. (author)
An improved method for calculation of interface pressure force in PLIC-VOF methods
International Nuclear Information System (INIS)
Conventional methods for the modeling of surface tension force in Piecewise Linear Interface Calculation-Volume of Fluid (PLIC-VOF) methods, such as Continuum Surface Force (CSF), Continuum Surface Stress (CSS) and also Meier's method, convert the surface tension force into a body force. Not only do they include the force in the interfacial cells but also in the neighboring cells. Thus they produce spurious currents. Also the pressure jump, due to the surface tension, is not calculated accurately in these methods. In this paper a more accurate method for the application of interface force in the computational modeling of free surfaces and interfaces which use PLIC-VOF methods is developed. This method is based on the evaluation of the surface tension force only in the interfacial cells and not the neighboring cells. Also the normal and the interface surface area needed for the calculation of the surface tension force is calculated more accurately. The present method is applied to a two-dimensional motionless drop of liquid and a bubble of gas as well as a non-circular two-dimensional drop, which oscillates due to the surface tension force, in an initially stagnant fluid with no gravity force. The results are compared with the results of the cases when CSF, CSS and Meier's methods are used. It is shown that the present method calculates pressure jump at the interface more accurately and produces less spurious currents comparing to CSS an CSF models. (author)
Present HTR physics calculational methods at the Paul Scherrer Institute
International Nuclear Information System (INIS)
In this paper a general description of HTR related calculational methods and data available at the Paul Scherrer Institute (PSI) is given. The cell codes used are MICROX-2, WIMS-D, and TRAMIX. MICROX-2 is an integral transport theory spectrum code which solves the neutron slowing down and thermalization equations on a detailed energy grid for a two region lattice cell. A second level of heterogeneity can be treated, i.e. the inner region may include two different types of grains (particles). WIMS-D contains tabulations of temperature dependent resonance integrals accurately evaluated for homogeneous mixtures of moderator and absorber at many energy points. Equivalence theorems are utilized to obtain few-group effective cross sections in heterogeneous problems. The intermediate resonance absorption shielding (IR) method of resolved resonances is employed. The spherical geometry of the pebble can be converted into an equivalent cylindrical geometry, and the double heterogeneity can be treated using the available cluster option with a method developed by Segev. TRAMIX is a flexible computer (cell) code which reads fine group nuclear data from a library in the Los Alamos National Laboratory (LANL) format MATXS and produces fine group cross sections using the IR methods. Self-shielded multigroup cross sections produced with these cell codes can be used in connection with the one- and two-dimensional discrete-ordinates finite difference transport codes ONEDANT and TWODANT from LANL for full reactor calculations. Additional interface modules which are available include a BN module for leakage calculations and some library management codes plus the PERT-V diffusion perturbation theory code. Most of the nuclear data libraries for the cell codes are based on the JEF-1 (Joint European File) evaluation. They were processed using the NJOY nuclear data processing system from LANL with additional PSI developments. These libraries include the fast, thermal and resonance data tapes
Calculation methods for single-sided natural ventilation - simplified or detailed?
DEFF Research Database (Denmark)
Larsen, Tine Steen; Plesner, Christoffer; Leprince, Valérie
2016-01-01
) airflow. The predicted airflow rate from the new and three existing design expressions are compared to full-scale wind tunnel measurements. The new proposed calculation method for single-sided ventilation shows results, limiting the overestimation of air flow rates at especially low driving pressures...... handled. This paper presents a newly developed simplified calculation method for single-sided natural ventilation, which is proposed for the revised standard FprEN 16798-7 (earlier EN 15242:2007) for design of ventilative cooling. The aim for predicting ventilative cooling is to find the most suitable......, while maintaining an acceptable correlation with measurements on average and the authors consider the simplified calculation method well suited for the use in standards such as FprEN 16798-7 for the ventilative cooling effects from single-sided natural ventilation The comparison of different design...
Calculation and measurement of build-up factors in divergent gamma radiation beams
International Nuclear Information System (INIS)
The methods and the results are presented of the calculation and experimental determination of build-up factors in a broad divergent gamma radiation beam passing through a planar layer of material. A computer program based on the Monte Carlo method is described as is the experimental configuration used. The dependence was determined of the build-up factor on the beam collimation angle, the distance of the source and the distance of the detector from the layer to be radiographed. No dependence was confirmed on the detector diameter. The measurements conducted confirmed agreement with the calculated results within the maximum error limit of +-10%. The results of calculation and measurements are shown in graphs
An improved method for calculating control rod reactivity worths in fast sodium cooled reactor cores
International Nuclear Information System (INIS)
An improved method is presented to determine the reactivities of strongly inhomogeneous control rod arrangements in fast sodium cooled reactor cores. The method is based on a detailed evaluation of the multiplication constants for the rods embedded in a large surrounding of fuel material. These calculations are performed using two-dimensional transport theory, with an accurate representation of the actual geometry in RΘ coordinates and with fine discretizations in coordinate space and energy. Three-dimensional whole core calculations are carried out in diffusion approximation, with a coarse spatial hexagonal-Z mesh and few energy groups, replacing the individual reactor cells by homogeneous arrangements. The homogenized macroscopic group cross sections are generated with standard methods, however using reduced boron contents of the absorber pins as compared with their actual values. The appropriate boron concentrations are found by comparing the control rod reactivity worths resulting from the two-dimensional transport calculations with those determined from corresponding diffusion calculations with homogenized compositions for the corresponding regions, which possess as many features of the final whole core calculations as possible. In this way, the corrections necessitated by the heterogeneity, transport, mesh, and condensation effects are incorporated in the macroscopic cross sections. With these as input, the computed rod worths of the secondary shutdown system of the SUPERPHENIX-1 (SPX-1) power production core are essentially improved as compared with results of earlier calculations. This progress of the calculational method is clearly demonstrated by a comparison with measured reactivity worths. (orig.)
About possibilities using of theoretical calculation methods in radioecology
International Nuclear Information System (INIS)
Full text: Increasing the radiation level into environment is accompanied by accumulation of radioactive compounds into organism and/or their migration into biosphere. Radiotoxins are accumulated into irradiated plants and animals in result of violation of exchanging processes. The are play an important role at the pathogenesis of irradiation. To date, there is well known that even small quantity of the pesticides capable intensified the radiation effect. To understand the mechanism of radiation effect on physiologically active compounds and their complexes, the knowledge of such molecules three-dimensional organization and electron structure is essential. This work is devoted to study the pesticides of carbamate range, i.e. 'sevin' and its derivatives the physiological activity of which has been connected with cholinesterase degradation. Spatial organization and conformational possibilities of the pesticides has been studied using a method of the theoretical conformational analysis on the base of computational program worked out in laboratory of Molecular Biophysics at the Baku State University. Quantum-chemical methods CNDO/2, AM1 and PM3 and complex programs 'LEV' were used in studies of electronic structures of 'sevin' and number of its analogues. Charge distribution on the atoms, optimization of geometrical electrooptic parameters, as well as molecular electrostatic potentials, electron density and nuclear forces were calculated. Visual maps and surface of valence electron density distribution in the given plane and surface of electron-nuclear forces distribution projection were constructed. The geometrical and energetic characteristics, charges on the atoms of investigated pesticides, as well as the maps and relief of the valence electron density distribution on the atoms have been received. According to calculation results, the changing of charge distribution in naphthalene ring is observed. The conclusion was made that the carbonyl group is essential for
METHOD FOR CALCULATION OF STRESSED STATE SUBSTANTIATED BY DYNAMIC MICROTWIN
Directory of Open Access Journals (Sweden)
V. V. Vlashevich
2015-01-01
Full Text Available Method for calculation of the stressed state in a dynamic twin has been developed on the basis of a non-thin non-coherent micro-twin model with continuous distribution of twinning dislocations at twin boundaries. In this case there is no additional generation with the help of twinning dislocation source. The model takes into account that the twin has coherent and noncoherent boundary sections. The developed model has made it possible to take into consideration a form of non-coherent sections of twinning boundaries in calculations of stressed and deformed state at dynamic twins. It has been established that localized stresses are migrating together with non-coherent sections of the twin. Normal stresses σxx change their sign in relation to direction of the twin development. Shear stresses σxy are alternating in signs in relation to an axis which is perpendicular to the direction of the twin development and which is passing through a mid-point of non-coherent twin section. Distribution of stresses σyy и σyz has similar configuration. Stresses σzx in the second and fourth quarters of XOY plane are negative and the stresses in the first and third quarters are positive. Distribution of stresses σzz practically does not differ from distribution of stresses σyy according to configuration but numerical values of stress tensor component data are different.The results have been obtained without thin twin model that permits to consider only elastic stage of the twinning process. The executed stress calculations at dynamic twin are important for forecasting at the accumulation stage of damage origination which is caused by twinning destruction and permit to improve forecasting accuracy of technical system resources on the basis of twinning materials such as alloys based on iron, copper, zinc, aluminium, titanium.
Method of Frisch grid inefficiency measurement
International Nuclear Information System (INIS)
A simple experimental method for measuring inefficiency of the Frisch grid in ionization chambers which are widely used for charged particles characteristics studies is proposed. Noncomplete shielding of the anode by Frisch grid influence on ionization chamber operation is discussed. It is shown that application of calculated grid inefficiency value can result in serious errors in particle energy determination. The conclusion is made that it is necessary to determine the grid inefficiency experimentally in order to get its correct value. The most precise method for the grid inefficiency determination is the analysis of the data obtained using gaseous α source. There no energy loss in the target and scattering in the backing in this method. Data can be obtained in the wide range of the cathode signals. Data analysis is obvious and simple. 7 refs., 6 figs
Output calculation of electron therapy at extended SSD using an improved LBR method
Energy Technology Data Exchange (ETDEWEB)
Alkhatib, Hassaan A.; Gebreamlak, Wondesen T., E-mail: wondtassew@gmail.com; Wright, Ben W.; Neglia, William J. [South Carolina Oncology Associates, Columbia, South Carolina 29210 (United States); Tedeschi, David J. [Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208 (United States); Mihailidis, Dimitris [CAMC Cancer Center and Alliance Oncology, Charleston, West Virginia 25304 (United States); Sobash, Philip T. [The Medical University of South Carolina, Charleston, South Carolina 29425 (United States); Fontenot, Jonas D. [Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, Louisiana 70809 (United States)
2015-02-15
Purpose: To calculate the output factor (OPF) of any irregularly shaped electron beam at extended SSD. Methods: Circular cutouts were prepared from 2.0 cm diameter to the maximum possible size for 15 × 15 applicator cone. In addition, two irregular cutouts were prepared. For each cutout, percentage depth dose (PDD) at the standard SSD and doses at different SSD values were measured using 6, 9, 12, and 16 MeV electron beam energies on a Varian 2100C LINAC and the distance at which the central axis electron fluence becomes independent of cutout size was determined. The measurements were repeated with an ELEKTA Synergy LINAC using 14 × 14 applicator cone and electron beam energies of 6, 9, 12, and 15 MeV. The PDD measurements were performed using a scanning system and two diodes—one for the signal and the other a stationary reference outside the tank. The doses of the circular cutouts at different SSDs were measured using PTW 0.125 cm{sup 3} Semiflex ion-chamber and EDR2 films. The electron fluence was measured using EDR2 films. Results: For each circular cutout, the lateral buildup ratio (LBR) was calculated from the measured PDD curve using the open applicator cone as the reference field. The effective SSD (SSD{sub eff}) of each circular cutout was calculated from the measured doses at different SSD values. Using the LBR value and the radius of the circular cutout, the corresponding lateral spread parameter [σ{sub R}(z)] was calculated. Taking the cutout size dependence of σ{sub R}(z) into account, the PDD curves of the irregularly shaped cutouts at the standard SSD were calculated. Using the calculated PDD curve of the irregularly shaped cutout along with the LBR and SSD{sub eff} values of the circular cutouts, the output factor of the irregularly shaped cutout at extended SSD was calculated. Finally, both the calculated PDD curves and output factor values were compared with the measured values. Conclusions: The improved LBR method has been generalized to
Output calculation of electron therapy at extended SSD using an improved LBR method
International Nuclear Information System (INIS)
Purpose: To calculate the output factor (OPF) of any irregularly shaped electron beam at extended SSD. Methods: Circular cutouts were prepared from 2.0 cm diameter to the maximum possible size for 15 × 15 applicator cone. In addition, two irregular cutouts were prepared. For each cutout, percentage depth dose (PDD) at the standard SSD and doses at different SSD values were measured using 6, 9, 12, and 16 MeV electron beam energies on a Varian 2100C LINAC and the distance at which the central axis electron fluence becomes independent of cutout size was determined. The measurements were repeated with an ELEKTA Synergy LINAC using 14 × 14 applicator cone and electron beam energies of 6, 9, 12, and 15 MeV. The PDD measurements were performed using a scanning system and two diodes—one for the signal and the other a stationary reference outside the tank. The doses of the circular cutouts at different SSDs were measured using PTW 0.125 cm3 Semiflex ion-chamber and EDR2 films. The electron fluence was measured using EDR2 films. Results: For each circular cutout, the lateral buildup ratio (LBR) was calculated from the measured PDD curve using the open applicator cone as the reference field. The effective SSD (SSDeff) of each circular cutout was calculated from the measured doses at different SSD values. Using the LBR value and the radius of the circular cutout, the corresponding lateral spread parameter [σR(z)] was calculated. Taking the cutout size dependence of σR(z) into account, the PDD curves of the irregularly shaped cutouts at the standard SSD were calculated. Using the calculated PDD curve of the irregularly shaped cutout along with the LBR and SSDeff values of the circular cutouts, the output factor of the irregularly shaped cutout at extended SSD was calculated. Finally, both the calculated PDD curves and output factor values were compared with the measured values. Conclusions: The improved LBR method has been generalized to calculate the output factor of
Renewable energy: Method and measures
International Nuclear Information System (INIS)
The thesis presents various possibilities for renewable energy in Norway. The wind power would give a practical and economic alternative. The external costs for the wind power would be moderate. In chapter 3 the utility cost analysis for renewable alternatives are studied relative to the macroeconomic efficiency. Some methodical problems and how these analyses are used are reviewed. In the practical utility cost analyses wind power is studied relative to gas power which is the non-renewable alternative present in Norway today. A qualitative part is included. It is not possible to determine whether wind power is preferable to gas power in the macroeconomic perspective. Wind power would be the choice if high environmental and CO2 cleaning costs are expected. The first conclusion to be drawn is that it is difficult to decide whether wind power is the best solution based on cost benefit analysis. However, the alternative seems to be quite robust in the analysis. Due to the central position the energy supplies have in the society this business should be heavily regulated. The sector is also overtaxed as a reduction in consumption is desired. The analysis shows that the system does not function perfectly. The thesis surveys various measures for improving the renewable energy supply and focuses on the wind power. A model for and analysis of the measures are carried out and resulted in a second conclusion. The measures have various properties as to the influence on the market. A subsidy is a fine measure for stimulation production of green power while a tax reduces efficiently the production of black power. A system with green licenses in combination with a subsidy and a tax would be preferable as to increasing the part of renewable energy of the total production. It is therefore necessary to have clearly defined goals and use suitable measures for achieving them. The costs of wind power is falling and it would therefore soon be macroeconomic profitable. It is also
Gradient type optimization methods for electronic structure calculations
Zhang, Xin; Wen, Zaiwen; Zhou, Aihui
2013-01-01
The density functional theory (DFT) in electronic structure calculations can be formulated as either a nonlinear eigenvalue or direct minimization problem. The most widely used approach for solving the former is the so-called self-consistent field (SCF) iteration. A common observation is that the convergence of SCF is not clear theoretically while approaches with convergence guarantee for solving the latter are often not competitive to SCF numerically. In this paper, we study gradient type methods for solving the direct minimization problem by constructing new iterations along the gradient on the Stiefel manifold. Global convergence (i.e., convergence to a stationary point from any initial solution) as well as local convergence rate follows from the standard theory for optimization on manifold directly. A major computational advantage is that the computation of linear eigenvalue problems is no longer needed. The main costs of our approaches arise from the assembling of the total energy functional and its grad...
NEW METHOD FOR CALCULATION OF STATISTIC MISTAKE IN MARKETING INVESTIGATIONS
Directory of Open Access Journals (Sweden)
V. A. Koldachiov
2015-01-01
Full Text Available An idea of a new method is that while breaking-down analysis sample in some sub-samples there is a probability that an actual value for general body will be inside the interval between the highest and lowest average meaning of sub-sample is much higher of the probability that the given value will be beyond the limits of the indicated interval. In this case a size of the interval appears to be less than analogous parameter while making calculation with the help of the Stewdent formula.Thus, it is possible to reach high accuracy in results of marketing investigations while preserving analysis sample size or reducing the necessary size of analysis sample while preserving level of statistical mistake.
Energy Savings Calculation Methods under Article 7 of the Energy Efficiency Directive
LABANCA NICOLA; BERTOLDI PAOLO
2015-01-01
The present report aims to provide an overview of the main issues at stake with the calculation methods for energy savings generated by measures implemented by EU Member States under Article 7 of the Directive 2012/27/EU on Energy Efficiency (EED).
A Method of Calculating Motion Error in a Linear Motion Bearing Stage
Directory of Open Access Journals (Sweden)
Gyungho Khim
2015-01-01
Full Text Available We report a method of calculating the motion error of a linear motion bearing stage. The transfer function method, which exploits reaction forces of individual bearings, is effective for estimating motion errors; however, it requires the rail-form errors. This is not suitable for a linear motion bearing stage because obtaining the rail-form errors is not straightforward. In the method described here, we use the straightness errors of a bearing block to calculate the reaction forces on the bearing block. The reaction forces were compared with those of the transfer function method. Parallelism errors between two rails were considered, and the motion errors of the linear motion bearing stage were measured and compared with the results of the calculations, revealing good agreement.
Comparing calculated and measured x-ray images
International Nuclear Information System (INIS)
In recent years 2-dimensional radiation-magneto-hydrodynamic (RMHD) calculations have done quite well in matching some important observed parameters of a z-pinch implosion. As the authors gain experience, they field more complex experiments to compare with calculations. Here they discuss both time dependent and time integrated x-ray imaging on Pegasus. Images, using similar filters, are calculated and compared with the data. They also apply some image enhancement to the data
Hamiltonian lattice field theory: Computer calculations using variational methods
International Nuclear Information System (INIS)
A variational method is developed for systematic numerical computation of physical quantities-bound state energies and scattering amplitudes-in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. An algorithm is presented for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. It is shown how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato's generalizations of Temple's formula. The algorithm could be adapted to systems such as atoms and molecules. It is shown how to compute Green's functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green's functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. The author discusses the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, the author does not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. The method is applied to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. The author describes a computer implementation of the method and present numerical results for simple quantum mechanical systems
Hamiltonian lattice field theory: Computer calculations using variational methods
International Nuclear Information System (INIS)
I develop a variational method for systematic numerical computation of physical quantities -- bound state energies and scattering amplitudes -- in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. I present an algorithm for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. I also show how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato's generalizations of Temple's formula. The algorithm could be adapted to systems such as atoms and molecules. I show how to compute Green's functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green's functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. I discuss the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, I do not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. I apply the method to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. I describe a computer implementation of the method and present numerical results for simple quantum mechanical systems
International Nuclear Information System (INIS)
A modified code system based on the point kernel method was developed to use in evaluation of shielding performance for maritime transport of radioactive material. For evaluation of shielding performance accurately in the case of accident, it is required to preciously model the structure of transport casks and shipping vessel, and source term. To achieve accurate modelling of the geometry and source term condition, we aimed to develop the code system by using equivalent information regarding structure and source term used in the Monte Carlo calculation code, MCNP. Therefore, adding an option to use point kernel method to the existing Monte Carlo code, MCNP4C, the code system was developed. To verify the developed code system, dose rate distribution in an exclusive shipping vessel to transport the low level radioactive wastes were calculated by the developed code and the calculated results were compared with measurements and Monte Carlo calculations. It was confirmed that the developed simple calculation method can obtain calculation results very quickly with enough accuracy comparing with the Monte Carlo calculation code MCNP4C
Improved Numerical Method for Calculation of 4-Body Transition Amplitudes
Harris, A. L.
2013-01-01
In order to study 4-body atomic collisions such as excitation-ionization, transfer with target excitation, and double electron capture, the calculation of a nine-dimensional numerical integral is often required. This calculation can become computationally expensive, especially when calculating fully differential cross sections (FDCS), where the positions and momenta of all the particles are known. We have developed a new technique for calculating FDCS using fewer computing hours, but more mem...
[Calculating method for crop water requirement based on air temperature].
Tao, Guo-Tong; Wang, Jing-Lei; Nan, Ji-Qin; Gao, Yang; Chen, Zhi-Fang; Song, Ni
2014-07-01
The importance of accurately estimating crop water requirement for irrigation forecast and agricultural water management has been widely recognized. Although it has been broadly adopted to determine crop evapotranspiration (ETc) via meteorological data and crop coefficient, most of the data in whether forecast are qualitative rather than quantitative except air temperature. Therefore, in this study, how to estimate ETc precisely only using air temperature data in forecast was explored, the accuracy of estimation based on different time scales was also investigated, which was believed to be beneficial to local irrigation forecast as well as optimal management of water and soil resources. Three parameters of Hargreaves equation and two parameters of McClound equation were corrected by using meteorological data of Xinxiang from 1970 to 2010, and Hargreaves equation was selected to calculate reference evapotranspiration (ET0) during the growth period of winter wheat. A model of calculating crop water requirement was developed to predict ETc at time scales of 1, 3, and 7 d intervals through combining Hargreaves equation and crop coefficient model based on air temperature. Results showed that the correlation coefficients between measured and predicted values of ETc reached 0.883 (1 d), 0.933 (3 d), and 0.959 (7 d), respectively. The consistency indexes were 0.94, 0.95 and 0.97, respectively, which showed that forecast error decreased with the increasing time scales. Forecasted accuracy with an error less than 1 mm x d(-1) was more than 80%, and that less than 2 mm x d(-1) was greater than 90%. This study provided sound basis for irrigation forecast and agricultural management in irrigated areas since the forecasted accuracy at each time scale was relatively high. PMID:25345053
Foil activity measurements for testing transport calculations in the Budapest Research Reactor
International Nuclear Information System (INIS)
The upgraded VVR-SM type (Russian design) Budapest Research Reactor serves both research and practical applications. As a by-product of the experimental methods used in the field of the neutron activation analysis a unique opportunity arose for benchmarking the neutron physical algorithms against measurements. As the original aim of the measurements was the determination of the concentrations and the necessary neutron flux characteristics, the measured primary data had to be reevaluated to verity the neutron physical calculations. The reaction rates of the following measured reactions were selected for the comparison: 94Zr(n,γ)95Zr, 96Zr(n,γ)97Zr/97mNb, 58Ni(n,p)58Co, 176Lu(n,γ)177Lu and 197Au(n,γ)198Au. For the sake of comparison, the multigroup cross section library of the MULTICELL code had been supplemented with the data of the above reactions by using the NJOY code. As the reaction rates are measured at the same positions (practically without shielding effects), the measured and calculated reaction rate ratios were compared on the level of the multigroup MULTICELL calculations. The accuracy of the MULTICELL code for the research reactor has been tested by comparative MCNP calculations. (author)
Meng, Qing-Xin; Pan, He-Ping; Luo, Miao
2015-12-01
We conducted a study on the numerical calculation and response analysis of a transient electromagnetic field generated by a ground source in geological media. One solution method, the traditional discrete image method, involves complex operation, and its digital filtering algorithm requires a large number of calculations. To solve these problems, we proposed an improved discrete image method, where the following are realized: the real number of the electromagnetic field solution based on the Gaver-Stehfest algorithm for approximate inversion, the exponential approximation of the objective kernel function using the Prony method, the transient electromagnetic field according to discrete image theory, and closed-form solution of the approximate coefficients. To verify the method, we tentatively calculated the transient electromagnetic field in a homogeneous model and compared it with the results obtained from the Hankel transform digital filtering method. The results show that the method has considerable accuracy and good applicability. We then used this method to calculate the transient electromagnetic field generated by a ground magnetic dipole source in a typical geoelectric model and analyzed the horizontal component response of the induced magnetic field obtained from the "ground excitation-stratum measurement" method. We reached the conclusion that the horizontal component response of a transient field is related to the geoelectric structure, observation time, spatial location, and others. The horizontal component response of the induced magnetic field reflects the eddy current field distribution and its vertical gradient variation. During the detection of abnormal objects, positions with a zero or comparatively large offset were selected for the drillhole measurements or a comparatively long observation delay was adopted to reduce the influence of the ambient field on the survey results. The discrete image method and forward calculation results in this paper
Automated Methods Of Corrosion Measurements
DEFF Research Database (Denmark)
Bech-Nielsen, Gregers; Andersen, Jens Enevold Thaulov; Reeve, John Ch;
1997-01-01
The chapter describes the following automated measurements: Corrosion Measurements by Titration, Imaging Corrosion by Scanning Probe Microscopy, Critical Pitting Temperature and Application of the Electrochemical Hydrogen Permeation Cell.......The chapter describes the following automated measurements: Corrosion Measurements by Titration, Imaging Corrosion by Scanning Probe Microscopy, Critical Pitting Temperature and Application of the Electrochemical Hydrogen Permeation Cell....
Integrating The Abc Method Of Costs Calculation And Cash Value Added
Marius Sorin DINCA; Gheorghita DINCA
2010-01-01
In our paper we intend to explore the possibility of integrating the ABC method of cost calcula-tion with cash based value measure, i.e. the Cash Value Added. Our purpose is to develop an instrument for the management of productive companies that will allow them to administrate the proc-ess of value creation at the level of individual products or services. The activity based costing (ABC) method of cost calculation can be extended to the way of allo-cating the capital costs to individual prod...
International Nuclear Information System (INIS)
Food consumption may account for upwards of 15% of U.S. per capita greenhouse gas emissions. Online carbon calculators can help consumers prioritize among dietary behaviors to minimize personal 'carbon footprints', leveraging against emissions-intensive industry practices. We reviewed the fitness of selected carbon calculators for measuring and communicating indirect GHG emissions from food consumption. Calculators were evaluated based on the scope of user behaviors accounted for, data sources, transparency of methods, consistency with prior data and effectiveness of communication. We found food consumption was under-represented (25%) among general environmental impact calculators (n = 83). We identified eight carbon calculators that accounted for food consumption and included U.S. users among the target audience. Among these, meat and dairy consumption was appropriately highlighted as the primary diet-related contributor to emissions. Opportunities exist to improve upon these tools, including: expanding the scope of behaviors included under calculations; improving communication, in part by emphasizing the ecological and public health co-benefits of less emissions-intensive diets; and adopting more robust, transparent methodologies, particularly where calculators produce questionable emissions estimates. Further, all calculators could benefit from more comprehensive data on the U.S. food system. These advancements may better equip these tools for effectively guiding audiences toward ecologically responsible dietary choices. (author)
Comparison of calculated and measured foliar O3 flux in crop and forest species
International Nuclear Information System (INIS)
We designed a new gas exchange system that concurrently measures foliar H2O, O3, and CO2 flux (HOC flux system) while delivering known O3 concentrations. Stomatal responses of three species were tested: snapbean, and seedlings of California black oak (deciduous broadleaf) and blue oak (evergreen broadleaf). Acute O3 exposure (120-250 ppb over an hour) was applied under moderate light and low vapor pressure deficits during near steady state conditions. The rate of stomatal closure was measured when the whole plant was placed in the dark. An adjacent leaf on each plant was also concurrently measured in an O3-free cuvette. Under some conditions, direct measurements and calculated foliar O3 flux were within the same order of magnitude; however, endogenously low gs or O3 exposure-induced depression of gs resulted in an overestimation of calculated O3 fluxes compared with measured O3 fluxes. Sluggish stomata in response to light extinction with concurrent O3 exposure, and incomplete stomatal closure likewise underestimated measured O3 flux. - Using a new system to concurrently measure H2O, O3, and CO2 flux, the conventional method of calculating O3 flux generally overestimated direct measures by 25-50%
Comparison of calculated and measured foliar O{sub 3} flux in crop and forest species
Energy Technology Data Exchange (ETDEWEB)
Grulke, N.E. [USDA Forest Service, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States)]. E-mail: ngrulke@fs.fed.us; Paoletti, E. [IPP-CNR, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Florence (Italy); Heath, R.L. [Botany and Plant Sciences Department, University of California, Riverside, CA 92521 (United States)
2007-04-15
We designed a new gas exchange system that concurrently measures foliar H{sub 2}O, O{sub 3}, and CO{sub 2} flux (HOC flux system) while delivering known O{sub 3} concentrations. Stomatal responses of three species were tested: snapbean, and seedlings of California black oak (deciduous broadleaf) and blue oak (evergreen broadleaf). Acute O{sub 3} exposure (120-250 ppb over an hour) was applied under moderate light and low vapor pressure deficits during near steady state conditions. The rate of stomatal closure was measured when the whole plant was placed in the dark. An adjacent leaf on each plant was also concurrently measured in an O{sub 3}-free cuvette. Under some conditions, direct measurements and calculated foliar O{sub 3} flux were within the same order of magnitude; however, endogenously low gs or O{sub 3} exposure-induced depression of gs resulted in an overestimation of calculated O{sub 3} fluxes compared with measured O{sub 3} fluxes. Sluggish stomata in response to light extinction with concurrent O{sub 3} exposure, and incomplete stomatal closure likewise underestimated measured O{sub 3} flux. - Using a new system to concurrently measure H{sub 2}O, O{sub 3}, and CO{sub 2} flux, the conventional method of calculating O{sub 3} flux generally overestimated direct measures by 25-50%.
Relative Hazard and Risk Measure Calculation Methodology Rev 1
International Nuclear Information System (INIS)
Documentation of the methodology used to calculate relative hazard and risk measure results for the DOE complex wide risk profiles. This methodology is used on major site risk profiles. In February 1997, the Center for Risk Excellence (CRE) was created and charged as a technical, field-based partner to the Office of Science and Risk Policy (EM-52). One of the initial charges to the CRE is to assist the sites in the development of ''site risk profiles.'' These profiles are to be relatively short summaries (periodically updated) that present a broad perspective on the major risk related challenges that face the respective site. The risk profiles are intended to serve as a high-level communication tool for interested internal and external parties to enhance the understanding of these risk-related challenges. The risk profiles for each site have been designed to qualitatively present the following information: (1) a brief overview of the site, (2) a brief discussion on the historical mission of the site, (3) a quote from the site manager indicating the site's commitment to risk management, (4) a listing of the site's top risk-related challenges, (5) a brief discussion and detailed table presenting the site's current risk picture, (6) a brief discussion and detailed table presenting the site's future risk reduction picture, and (7) graphic illustrations of the projected management of the relative hazards at the site. The graphic illustrations were included to provide the reader of the risk profiles with a high-level mental picture to associate with all the qualitative information presented in the risk profile. Inclusion of these graphic illustrations presented the CRE with the challenge of how to fold this high-level qualitative risk information into a system to produce a numeric result that would depict the relative change in hazard, associated with each major risk management action, so it could be presented graphically. This report presents the methodology developed
Calculating magnetic shielding effectiveness for high-power dc comparator by magnetic circuit method
Institute of Scientific and Technical Information of China (English)
WANG Xiao-wei; REN Shi-yan
2007-01-01
Magnetic shielding is very important in the design of a high-power dc comparator. This paper addressed the application of magnetic circuit method to calculate the magnetic shielding effectiveness of high-power dc comparators when an external radial magnetic field is added. The mathematical relationship between the magnetic shielding effectiveness and the parameters of the magnetic shielding body were obtained. To verify the validity of the calculation method, we developped a procedure to measure the magnetic shielding effectiveness of the magnetic body by measuring the induction voltage of the detection winding instead of the magnetic intensity at a point in the magnetic shielding body, making the manipulation much easier. The result calculated with the magnetic circuit method turns out to be closer to the measured one compared with that calculated with a conventional algorithm proposed by Ren, suggesting that the magnetic circuit method is an applicable tool for estimating the toroidal cavity magnetic shielding effectiveness of a heavy current comparator when a radial magnetic field is added.
Nanofibril Alignment in Flow Focusing: Measurements and Calculations.
Håkansson, Karl M O; Lundell, Fredrik; Prahl-Wittberg, Lisa; Söderberg, L Daniel
2016-07-14
Alignment of anisotropic supermolecular building blocks is crucial to control the properties of many novel materials. In this study, the alignment process of cellulose nanofibrils (CNFs) in a flow-focusing channel has been investigated using small-angle X-ray scattering (SAXS) and modeled using the Smoluchowski equation, which requires a known flow field as input. This flow field was investigated experimentally using microparticle-tracking velocimetry and by numerically applying the two-fluid level set method. A semidilute dispersion of CNFs was modeled as a continuous phase, with a higher viscosity as compared to that of water. Furthermore, implementation of the Smoluchowski equation also needed the rotational Brownian diffusion coefficient, which was experimentally determined in a shear viscosity measurement. The order of the nanofibrils was found to increase during extension in the flow-focusing channel, after which rotational diffusion acted on the orientation distribution, driving the orientation of the fibrils toward isotropy. The main features of the alignment and dealignment processes were well predicted by the numerical model, but the model overpredicted the alignment at higher rates of extension. The apparent rotational diffusion coefficient was seen to increase steeply as the degree of alignment increased. Thus, the combination of SAXS measurements and modeling provides the necessary framework for quantified studies of hydrodynamic alignment, followed by relaxation toward isotropy. PMID:27294285
Energy Technology Data Exchange (ETDEWEB)
Homb, Anders; Uvsloekk, Sivert
2012-11-01
SINTEF has carried out a project for Cultural Heritage and Enova to document specific qualities of energy-efficient and preservable windows. The work has been based on an older type two-rams window with simple frames and one glass divided into three squares of horizontal crossbars. There were produced two kinds of commodity window, respectively, with single glazing with Insulating. Measurements and calculations have been performed with two different distances from the outer glass to the last frame. The project had the following contents: Measurements of the U-value, Calculation of U-value of accurate and simplified method, Measurements of air density and drying ability, Measurement and evaluation of sound insulation, Estimation of the heat balance (eb)
IPR CURVE CALCULATING FOR A WELL PRODUCING BY INTERMITTENT GAS-LIFT METHOD
Directory of Open Access Journals (Sweden)
Zoran Mršić
2009-12-01
Full Text Available Master degree thesis (Mršić Z., 2009 shows the detailed procedure of calculating inflow performance curve for intermittent gas lift, based entirely on the data measured at surface. This article explains the detailed approach of the mentioned research and the essence of the results and observations acquired during the study. To evaluate the proposed method of calculating the average bottom hole flowing pressure (BHFP as the key parameter of inflow performance calculation, downhole pressure surveys have been conducted in three producing wells at Šandrovac and Bilogora oil fields: Šandrovac-75α, Bilogora-52 and Šandrovac-34. Absolute difference between measured and calculated values of average BHFP for first two wells was Δp=0,64 bar and Δp=0,06 bar while calculated relative error was εr=0,072 and εr=0,0038 respectively. Due to gas-lift valve malfunction in well Šandrovac-34, noticed during downhole pressure survey, value of calculated BHFP cannot be considered correct to compare with measured value. Based on the measured data the information have been revealed about actual values of a certain intermittent gas lift parameters that are usually assumed based on experience gained values or are calculated using empirical equations given in literature. The significant difference has been noticed for a parameter t2. The length of a minimum pressure period for which the measured values were in range of 10,74 min up to 16 min, while empirical equation gives values in the range of 1,23 min up to 1,75 min. Based on measured values of above mentioned parameter a new empirical equation has been established (the paper is published in Croatian.
Methods of measuring radioactivity in the environment
International Nuclear Information System (INIS)
A variety of sampling methods have been utilized to assess the amount of deposited activity, mainly from 137Cs, from the Chernobyl accident and from nuclear weapons tests. Starting with the Chernobyl accident in 1986 sampling of air and rain was used to determine the composition and amount of radioactive debris from this accident. The resulting deposition and its removal from urban areas was then studied through measurements on sewage sludge and water. The main part of the thesis considers methods of determining the amount of radiocesium in the ground through soil sampling. In connection with soil sampling a method of optimizing the sampling procedure has been developed and tested in the areas of Sweden with high amounts of 137Cs from the Chernobyl accident. This method was then used in a survey of the activity in soil in Scania (south Sweden) with fallout activity from nuclear weapons and Chernobyl. By comparing the results from this survey with deposition calculated from precipitation measurements it was found possible to predict the deposition pattern over Scania for both nuclear weapons and Chernobyl fallout. In addition, the vertical distribution of 137Cs has been modelled and the temporal variation of the depth distribution has been described. 65 refs
[The calculation of the intraocular lens power based on raytracing methods: a systematic review].
Steiner, Deborah; Hoffmann, Peter; Goldblum, David
2013-04-01
A problem in cataract surgery consists in the preoperative identification of the appropriate intraocular lens (IOL) power. Different calculation approaches have been developed for this purpose; raytracing methods represent one of the most exact but also mathematically more challenging methods. This article gives a systematic overview of the different raytracing calculations available and described in the literature and compares their results. It has been shown that raytracing includes physical measurements and IOL manufacturing data but no approximations. The prediction error is close to zero and an essential advantage is the applicability to different conditions without the need of modifications. Compared to the classical formulae the raytracing methods are more precise overall, but due to the various data and property situations they are hardly comparable yet. The raytracing calculations represent a good alternative to the 3rd generation formulae. They minimize refractive errors, are wider applicable and provide better results overall, particularly in eyes with preconditions. PMID:23629771
International Nuclear Information System (INIS)
The kerma heat production density, tritum production density, and dose in a lithium-fluoride pile with a deuterium-tritum neutron source were calculated with a data processing code, UFO, from the pulse height distribution of a miniature NE213 neutron spectrometer, and compared with the values calculated with a Monte Carlo code, MORSE-CV. Both the UFO and MORSE-CV values agreed with the statistical error (less than 6%) of the MORSE-CV calculations, except for the outer-most point in the pile. The MORSE-CV values were slightly smaller than the UFO values for almost all cases, and this tendency increased with increasing distance from the neutron source
Modified methods of stellar magnetic field measurements
Kholtygin, A F
2013-01-01
The standard methods of the magnetic field measurement, based on an analysis of the relation between the Stokes $V$-parameter and the first derivative of the total line profile intensity, were modified by applying a linear integral operator $\\hat{L}$ to the both sides of this relation. As the operator $\\hat{L}$, the operator of the wavelet transform with DOG-wavelets is used. The key advantage of the proposed method is an effective suppression of the noise contribution to the line profile and the Stokes parameter $V$. The efficiency of the method has been studied using the model line profiles with various noise contributions. To test the proposed method, the spectropolarimetric observations of the A0-type star $\\alpha^2\\,$ CVn, young O-type star $\\theta^1$ Ori C and A0 supergiant HD 92207 were used. The longitudinal magnetic field strengths for these stars calculated by our method appeared to be in a good agreement with those determined by other methods.
Calculation and measurement of kinetic parameters of Pakistan Research Reactor-1 (PARR-1)
Energy Technology Data Exchange (ETDEWEB)
Muhammad, Atta, E-mail: atta1974pk@yahoo.co [Department of Nuclear Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), P.O. Nilore, Islamabad 45650 (Pakistan); Nuclear Engineering Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), P.O. Nilore, Islamabad 45650 (Pakistan); Iqbal, Masood, E-mail: masiqbal@hotmail.co [Nuclear Engineering Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), P.O. Nilore, Islamabad 45650 (Pakistan); Mahmood, Tyyab; Qadir, Javed [Nuclear Engineering Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), P.O. Nilore, Islamabad 45650 (Pakistan)
2011-01-15
Rossi-Alpha ({beta}{sub eff}/{Lambda}) for critical reactor measured experimentally by noise analysis technique at PARR-1 core at 35.26 full power days burn up. In noise analysis technique the inherent reactivity fluctuations are taken as input to reactor system and the neutron density population fluctuations are considered as output of the reactor system. The auto power spectral density of the linear channel is taken and used to find out the break frequency by non-linear least square fitting method, which leads to {beta}{sub eff}/{Lambda} = 161.45 s{sup -1}. Calculations were performed with the help of computer codes WIMSD/4 and CITATION. The calculated {beta}{sub eff}/{Lambda} = 161.07 s{sup -1} at 35.26 full power days burn up. The measured and calculated values for Rossi-Alpha are in good agreement within 0.235% of error.
Calculation and measurement of kinetic parameters of Pakistan Research Reactor-1 (PARR-1)
International Nuclear Information System (INIS)
Rossi-Alpha (βeff/Λ) for critical reactor measured experimentally by noise analysis technique at PARR-1 core at 35.26 full power days burn up. In noise analysis technique the inherent reactivity fluctuations are taken as input to reactor system and the neutron density population fluctuations are considered as output of the reactor system. The auto power spectral density of the linear channel is taken and used to find out the break frequency by non-linear least square fitting method, which leads to βeff/Λ = 161.45 s-1. Calculations were performed with the help of computer codes WIMSD/4 and CITATION. The calculated βeff/Λ = 161.07 s-1 at 35.26 full power days burn up. The measured and calculated values for Rossi-Alpha are in good agreement within 0.235% of error.
Measurement and Monte Carlo Calculation of Waste Drum Filled With Radioactive Aqueous Solution
Institute of Scientific and Technical Information of China (English)
XU; Li-jun; ZHANG; Wei-dong; YE; Hong-sheng; LIN; Min; CHEN; Xi-lin; GUO; Xiao-qing
2012-01-01
<正>Theoretically the best calibrating source of gamma scan system (SGS) is a waste drum filled with uniform distribution of medium and radioactive nuclides. However, in reality, waste drums usually full of solid substance, which are difficult to be prepared in a completely uniformly distributed state. To reduce measurement uncertainty of the radioactivity of waste drums prepared using the method of shell source, a waste drum filled with radioactive aqueous solution was prepared. Besides, its radioactivity was measured by a SGS device and calculated using Monte Carlo method to verify the exact geometric model, which
Reactor calculation in coarse mesh by finite element method applied to matrix response method
International Nuclear Information System (INIS)
The finite element method is applied to the solution of the modified formulation of the matrix-response method aiming to do reactor calculations in coarse mesh. Good results are obtained with a short running time. The method is applicable to problems where the heterogeneity is predominant and to problems of evolution in coarse meshes where the burnup is variable in one same coarse mesh, making the cross section vary spatially with the evolution. (E.G.)
Complex dielectric constant measurements by the microwave resonant cavities method
International Nuclear Information System (INIS)
A complex dielectric constant measurement method for solids, using cylindrical and parallelipipedic microwave resonant cavities is presented. This method provides high accuracy when calculating the value of epsilonsup(*) for dielectric, semiconductor, ferroelectric and ferromagnetic materials. The paper contains a short theoretical approach, the description of the experimental method, as well as some experimental results obtained in the frequency band (19500 MHz). (author)
CALCULATION OF MILL RIGIDITY BY THREE DIMENSION CONTACT BOUNDARY ELEMENT METHOD
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Vertical rigidity of the space self-adaptive 530 high rigidity mill is calculated by applying the boundary element method (BEM) of three-dimension elastic contact problem,which can update the existed deforming separation calculating theory and corresponding methods of material mechanics,elastic mechanics and finite element method.The method has less hypotheses and stronger synthesis in contact-type calculating model.The advantages of the method are high calculating rate,high calculating accuracy,etc..
International Nuclear Information System (INIS)
Analysis is made for the effect of mathematical model accuracy of the system concerned on the calculation results using the BRAND program system. Consideration is given to the impact of the following factors: accuracy of neutron source energy-angular characteristics description, various degrees of system geometry approximation, adequacy of Monte-Carlo method estimation to a real physical neutron detector. The calculation results analysis is made on the basis of the experiments on leakage neutron spectra measurement in spherical lead assemblies with the 14 MeV-neutron source in the centre. 4 refs.; 2 figs.; 10 tabs
IMAGE PROCESSING METHOD TO MEASURE SUGARCANE LEAF AREA
Directory of Open Access Journals (Sweden)
Sanjay B. Patil
2011-08-01
Full Text Available In order to increase the average sugarcane yield per acres with minimum cost farmers are adapting precision farming technique. This paper includes the area measurement of sugarcane leaf based on image processing method which is useful for plants growth monitoring, to analyze fertilizer deficiency and environmental stress,to measure diseases severity. In image processing method leaf area is calculated through pixel number statistic. Unit pixel in the same digital images represent the same size hence from known reference area and pixel count, unit pixel size can calculate, so that it is easy to calculate leaf area by counting total pixel in leaf area region. The results are compared with the results of graphical area measurement method. The experimentally it is proved that image processing method for measuring sugarcane leaf area is accurate and strong practicabilitywith small relative error.
A comparison of measured and calculated values of air kerma rates from 137Cs in soil
Directory of Open Access Journals (Sweden)
V. P. Ramzaev
2016-01-01
Full Text Available In 2010, a study was conducted to determine the air gamma dose rate from 137Cs deposited in soil. The gamma dose rate measurements and soil sampling were performed at 30 reference plots from the south-west districts of the Bryansk region (Russia that had been heavily contaminated as a result of the Chernobyl accident. The 137Cs inventory in the top 20 cm of soil ranged from 260 kBq m–2 to 2800 kBq m–2. Vertical distributions of 137Cs in soil cores (6 samples per a plot were determined after their sectioning into ten horizontal layers of 2 cm thickness. The vertical distributions of 137Cs in soil were employed to calculate air kerma rates, K, using two independent methods proposed by Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] and Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. A very good coincidence between the methods was observed (Spearman’s rank coefficient of correlation = 0.952; P<0.01; on average, a difference between the kerma rates calculated with two methods did not exceed 3%. The calculated air kerma rates agreed with the measured dose rates in air very well (Spearman’s coefficient of correlation = 0.952; P<0.01. For large grassland plots (n=19, the measured dose rates were on average 6% less than the calculated kerma rates. The tested methods for calculating the air dose rate from 137Cs in soil can be recommended for practical studies in radiology and radioecology.
Large subcriticality measurement by pulsed neutron method
International Nuclear Information System (INIS)
To establish the method determining large subcriticalities in the field of nuclear criticality safety, the authors performed pulsed neutron experiments using the Kyoto University Critical Assembly (KUCA) at Research Reactor Institute, Kyoto University and the Cockcroft-Walton type accelerator attached to the assembly. The area-ratio method proposed by Sjoestrand was employed to evaluate subcriticalities from neutron decay curves measured. This method has the shortcomings that the neutron component due to a decay of delayed neutrons remarkably decreases as the subcriticality of an objective increases. To overcome the shortcoming, the authors increased the frequency of pulsed neutron generation. The integral-version of the area-ratio method proposed by Kosaly and Fisher was employed in addition in order to remove a contamination of spatial higher modes from the decay curve. The latter becomes significant as subcriticality increases. The largest subcriticality determined in the present experiments was 125.4 dollars, which was equal to 0.5111 in a multiplication factor. The calculational values evaluated by the computer code KENO-IV with 137 energy groups based on the Monte Carlo method agreed well with those experimental values
Calculation method of quantum efficiency to TiO2 nanocrystal photocatalysis reaction
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The quantum yield is an important factor to evaluate the efficiency of photoreactor. This article gives an overall calculation method of the quantum efficiency(ф) and the apparent quantum efficiency(ф2) to the TiO2/UV photocatalysis system. Furthermore, for the immobility system (IS), the formulation of the faction of light absorbed by the TiO2 thin film is proposed so as to calculate the quantum efficiency by using the measured value and theoretic calculated value of transmissivity (T). For the suspension system(SS), due to the difficulty to obtain the absorption coefficient (α) of TiO2 particulates, the quantum efficiency is calculated by means of the relative photonic efficiency (ξr) and the standard quantum yield (фstandard).
Cost calculation and financial measures for high-level waste disposal business
International Nuclear Information System (INIS)
A study is made on the costs for disposal of high-level wastes, centering on financial problems involving cost calculation for disposal business and methods and systems for funding the business. The first half of the report is focused on calculation of costs for disposal business. Basic equations are shown to calculate the total costs required for a disposal plant and the costs for disposal of one unit of high-level wastes. A model is proposed to calculate the charges to be paid by electric power companies to the plant for disposal of their wastes. Another equation is derived to calculate the disposal charge per kWh of power generation in a power plant. The second half of the report is focused on financial measures concerning expenses for disposal. A financial basis should be established for the implementation of high-level waste disposal. It is insisted that a reasonable method for estimating the disposal costs should be set up and it should be decided who will pay the expenses. Discussions are made on some methods and systems for funding the disposal business. An additional charge should be included in the electricity bill to be paid by electric power users, or it should be included in tax. (Nogami, K.)
Czech Academy of Sciences Publication Activity Database
Kořínek, Radim; Bartušek, Karel; Vondrák, I.; Musil, M.
Bratislava : Slovak Academy of Sciences, 2011, s. 131-134. ISBN 978-80-969672-4-7. [International Conference on Measurement 2011 /8./. Smolenice (SK), 27.04.2011-30.04.2011] R&D Projects: GA MŠk ED0017/01/01 Institutional research plan: CEZ:AV0Z20650511 Keywords : T2 relaxation * diffusion * NMR * measurement Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
Methods for High Power EM Pulse Measurement
Fiala, P.; Drexler, P.
2006-01-01
There are some suitable methods for the measurement of ultra-short solitary electromagnetic pulses that can be generated by high power pulsed generators. The measurement methods properties have to correspond to the fact whether we want to measure pulses of voltage, current or free-space electromagnetic wave. The need for specific measurement methods occurred by the development of high power microwave pulse generator. Applicable methods are presented in this paper. The method utilizing Faraday...
Directory of Open Access Journals (Sweden)
Jie Yang
2011-09-01
Full Text Available We report a relatively precise method of conductivity measurement in a diamond anvil cell with axis symmetrical electrodes and finite difference calculation. The axis symmetrical electrodes are composed of two parts: one is a round thin-film electrode deposited on diamond facet and the other is the inside wall of metal gasket. Due to the asymmetrical configuration of the two electrodes, finite difference method can be applied to calculate the conductivity of sample, which can reduce the measurement error.
Analysis of shielding calculation methods for 16- and 64-slice computed tomography facilities
Energy Technology Data Exchange (ETDEWEB)
Moreno, C; Cenizo, E; Bodineau, C; Mateo, B; Ortega, E M, E-mail: c_morenosaiz@yahoo.e [Servicio de RadiofIsica Hospitalaria, Hospital Regional Universitario Carlos Haya, Malaga (Spain)
2010-09-15
The new multislice computed tomography (CT) machines require some new methods of shielding calculation, which need to be analysed. NCRP Report No. 147 proposes three shielding calculation methods based on the following dosimetric parameters: weighted CT dose index for the peripheral axis (CTDI{sub w,per}), dose-length product (DLP) and isodose maps. A survey of these three methods has been carried out. For this analysis, we have used measured values of the dosimetric quantities involved and also those provided by the manufacturer, making a comparison between the results obtained. The barrier thicknesses when setting up two different multislice CT instruments, a Philips Brilliance 16 or a Philips Brilliance 64, in the same room, are also compared. Shielding calculation from isodose maps provides more reliable results than the other two methods, since it is the only method that takes the actual scattered radiation distribution into account. It is concluded therefore that the most suitable method for calculating the barrier thicknesses of the CT facility is the one based on isodose maps. This study also shows that for different multislice CT machines the barrier thicknesses do not necessarily become bigger as the number of slices increases, because of the great dependence on technique used in CT protocols for different anatomical regions.
Methods for reactor physics calculations for control rods in fast reactors
International Nuclear Information System (INIS)
The IAEA Specialists' Meeting on ''Methods for Reactor Physics Calculations for Control Rods in Fast Reactors'' was held in Winfrith, United Kingdom, on 6-8 December, 1988. The meeting was attended by 23 participants from nine countries. The purpose of the meeting was to review the current calculational methods and their accuracy as assessed by theoretical studies and comparisons with measurements, and then to identify the requirements for improved methods or additional studies and comparisons. The control rod properties or effects to be considered were their reactivity worths, their effect on the power distribution through the core, and the reaction rates and energy deposition both within and adjacent to the rods. The meeting was divided into five sessions, in the first of which each national delegation presented a brief overview of their programme of work on calculational methods for fast reactor control rods. In the next three sessions a total of seventeen papers were presented describing calculational methods and assessments of their accuracy. The final session was a discussion to draw conclusions regarding the current status of methods and the further developments and validation work required. A separate abstract was prepared for each of the 23 papers presented at the meeting. Refs, figs and tabs
Method for Calculating Performance of Three-Phase Line-Start Permanent-Magnet Synchronous Motor
Takegami, Tsuneo; Tsuboi, Kazuo; Hirotsuka, Isao; Nakamura, Masanori
A three-phase line-start permanent-magnet synchronous motor (three-phase LSPMM) is expected to operate with ultrahigh efficiency because it can start as an induction motor and can then operate as a permanent-magnet synchronous motor. In a previous study, we developed a practical analytical theory for a three-phase LSPMM on the basis of a tensor analysis. Then, we developed (1) a method for calculating the asynchronous starting characteristics and synchronous operating characteristics of the three-phase LSPMM on the basis of the developed analytical theory and (2) a method for determining the constants of the three-phase LSPMM. Herein, we report the results of a comparison between the calculated and measured asynchronous starting characteristics and synchronous operating characteristics of a test three-phase LSPMM. The comparison results show that the developed calculation method is highly efficient and that the results obtained by using it are sufficiently precise, and therefore, the method is suitable for practical use. Furthermore, we propose a method for improving the starting performance of the three-phase LSPMM, on the basis of simulations performed using the calculation method.
Radioisotope method for measuring photorespiration of plants
International Nuclear Information System (INIS)
A method is suggested for direct measuring CO2 emission velocity from plant leaves and intracell decar boxylation velocity of photosynthesis intermediate products. On the basis of these factors interleave reassimilation can be calculated and carboxylation velocity can be determind. In measuring 14CO2 emission velocity in light, leaves are illucidated in 14CO2 medium for reaching photosynthesis stationary speed, and then they are exposed in the medium with 14CO2 up to the photorespiration substrate saturation by labell. After exposure in 14CO2 the chamber cleaning follows, carried out by its blowing with CO2 during 5S. After that the chamber is attached to a close system, in which 14CO2 radioactivity from a leaf is measured and recorded by a Geiger counter every 5S emitted. All the procedures described are carried out in a multichannel exposition chamber, providing a quick change of gaseous medium composition, around a leaf. In measuring 14CO2 emission from leaf experimental conditions during all 4 stages of the experiment and photosynthesis stationary state remain stable
Study on peak shape fitting method in radon progeny measurement
International Nuclear Information System (INIS)
Alpha spectrum measurement is one of the most important methods to measure radon progeny concentration in environment. However, the accuracy of this method is affected by the peak tailing due to the energy losses of alpha particles. This article presents a peak shape fitting method that can overcome the peak tailing problem in most situations. On a typical measured alpha spectrum curve, consecutive peaks overlap even their energies are not close to each other, and it is difficult to calculate the exact count of each peak. The peak shape fitting method uses combination of Gaussian and exponential functions, which can depict features of those peaks, to fit the measured curve. It can provide net counts of each peak explicitly, which was used in the Kerr method of calculation procedure for radon progeny concentration measurement. The results show that the fitting curve fits well with the measured curve, and the influence of the peak tailing is reduced. The method was further validated by the agreement between radon equilibrium equivalent concentration based on this method and the measured values of some commercial radon monitors, such as EQF3220 and WLx. In addition, this method improves the accuracy of individual radon progeny concentration measurement. Especially for the 218Po peak, after eliminating the peak tailing influence, the calculated result of 218Po concentration has been reduced by 21 %. (authors)
Study on peak shape fitting method in radon progeny measurement.
Yang, Jinmin; Zhang, Lei; Abdumomin, Kadir; Tang, Yushi; Guo, Qiuju
2015-11-01
Alpha spectrum measurement is one of the most important methods to measure radon progeny concentration in environment. However, the accuracy of this method is affected by the peak tailing due to the energy losses of alpha particles. This article presents a peak shape fitting method that can overcome the peak tailing problem in most situations. On a typical measured alpha spectrum curve, consecutive peaks overlap even their energies are not close to each other, and it is difficult to calculate the exact count of each peak. The peak shape fitting method uses combination of Gaussian and exponential functions, which can depict features of those peaks, to fit the measured curve. It can provide net counts of each peak explicitly, which was used in the Kerr method of calculation procedure for radon progeny concentration measurement. The results show that the fitting curve fits well with the measured curve, and the influence of the peak tailing is reduced. The method was further validated by the agreement between radon equilibrium equivalent concentration based on this method and the measured values of some commercial radon monitors, such as EQF3220 and WLx. In addition, this method improves the accuracy of individual radon progeny concentration measurement. Especially for the (218)Po peak, after eliminating the peak tailing influence, the calculated result of (218)Po concentration has been reduced by 21 %. PMID:25920795
Dynamic Calculation Method of Beam System Under Low Velocity Impact
Institute of Scientific and Technical Information of China (English)
LI Wen-pei; WANG De-rong; SONG Chun-ming; WANG Ming-yang
2008-01-01
The beating beams and the supporting beams under low velocity impact may be in four different strain stages of deformation depending on the impact intensity and beam structure strength. Based on the different judging conditions of deformation stages, the corresponding calculation models are proposed, the calculation formulae for the determination of the impact force and the beam's lateral displacement are obtained. Calculation shows that the beam's total deflection is small when the flexibility of the supporting component is high and the effect of diminishing deflection disappears almost when the stiffness of the supporting component is high.
A calculation method of plant similarity giving consideration to different plant features.
Ding, Wei-long; Wu, Shui-sheng; Max, Nelson; Wu, Fu-li; Xu, Li-feng
2015-12-21
A method to compute the similarity between different plants is proposed, using features of a plant׳s topological structure and peripheral contour, as well as its geometry. The topological structures are described using tree graphs, and their similarity can be calculated based on the edit distance of these graphs. The peripheral contour of a plant is abstracted by its three-dimensional convex hull, which is projected in several directions. The similarity of the different projections is calculated by an algorithm to compute the similarity of two-dimensional shapes. The similarity of the geometrical detail is computed by considering the geometrical properties of different level branches. Finally the overall similarity between different plants is calculated by combining these different similarity measures. The validity of proposed method is evaluated by detailed experiments. PMID:26408336
International Nuclear Information System (INIS)
In view of the problems of SDR and Tim-Coates models in calculating permeability using nuclear magnetic resonance logging data, based on the fact that nuclear magnetic resonance T2 distribution and capillary pressure curves reflect the reservoir pore structure, a method was presented to calculate reservoir permeability using nuclear magnetic resonance logging and capillary pressure data. The correlation between Swanson parameter and permeability was established by comparing 31 core samples which were measured by mercury penetration and nuclear magnetic resonance logging. Considering the problem that capillary pressure data are limited by their quantity, the good correlativity between T2 geometric mean value of lateral relaxation time of nuclear magnetic resonance and Swanson parameter can be used to determine the Swanson parameter and to calculate reservoir permeability consecutively. The processing of the data in well A yields a permeability closer to the result of core analysis, and this indicates the accuracy of the method. (authors)
Dynamic Inertia Measurement Method Project
National Aeronautics and Space Administration — Critically important inertia measurements are complex and expensive to obtain due to the extensive fixturing and custom instrumentation of conventional...
Comparison of Different Methods for Calculating Gyrotron Quasi-Optical Mode Converters
Gashturi, A. P.; Chirkov, A. V.; Denisov, G. G.; Paveliev, A. B.
2013-01-01
This paper presents the use of combination of three methods for calculation and synthesis of high-efficiency microwave mode converters, such as radiators of gyrotrons. The analytical method yields immediate estimates of mode converter dimensions, the Scalar Integral Equation (SIE) allows one to synthesize efficiently the optimal profile of the mode converter, and the most accurate Electric Field Integral Equation (EFIE) is used to check all transmission characteristics of the converter including calculations of reflection and cross-polarization. The combination of these three methods is an optimal for the mode converter design. Just so the launcher was designed for a quasi-optical mode converter used in the 60 GHz gyrotron in the TE7,3 operating mode. The simulation results agree well with the measured data. The paper also presents for the first time an accurate derivation of the SIE method.
Estonian oil shale resources calculated by GIS method
International Nuclear Information System (INIS)
A digital map of Estonian oil shale mining was created for joining the data about technological, environmental, and social limitations in the deposit. For evaluating potential resource of oil shale, based on borehole database, its amount, tonnage and energy were calculated. Thereafter the quantity of economical oil shale for power plants and shale oil resource were calculated. Energy rating is the most important factor for determining oil shale reserves in the case of using it for electricity generation. In the case of oil production, data on oil yield and potential resources in oil shale are the most important figures to determine the value of the deposit. Basing on the models, oil resource has been calculated. Resource data can be used for composing master plans for the deposit considering both power generation and oil production. The data can be also used for composing development plans of mines and for logistics calculations. (author)
Comparison of Methods for Calculating Radiative Heat Transfer
Energy Technology Data Exchange (ETDEWEB)
Schock, Alfred; Abbate, M J
2012-01-19
Various approximations for calculating radioactive heat transfer between parallel surfaces are evaluated. This is done by applying the approximations based on total emissivities to a special case of known spectral emissivities, for which exact heat transfer calculations are possible. Comparison of results indicates that the best approximation is obtained by basing the emissivity of the receiving surface primarily on the temperature of the emitter. A specific model is shown to give excellent agreement over a very wide range of values.
An approximate method for calculating the deformation of rotating nuclei
International Nuclear Information System (INIS)
The author presents as a collective model where the potential surface at spin I=0 is calculated in the Nilsson-Strutinsky model, an analytical expression for the moment of inertia is used which depends on the deformation and the pairing gaps for protons and neutrons, and the energy is minimized with respect to these gaps. Calculations in this model are performed for 16Oyb. (HSI)
A mathematical method to calculate efficiency of BF3 detectors
Institute of Scientific and Technical Information of China (English)
SI Fenni; HU Qingyuan; PENG Taiping
2009-01-01
In order to calculate absolute efficiency of the BF3 detector, MCNP/4C code is applied to calculate rela-tive efficiency of the BF3 detector first, and then absolute efficiency is figured out through mathematical techniques. Finally an energy response curve of the BF3 detector for 1~20 MeV neutrons is derived. It turns out that efficiency of BF3 detector are relatively uniform for 2~16 MeV neutrons.
International Nuclear Information System (INIS)
Computer development has a bearing on the choice of methods and their possible uses. The authors discuss the possible uses of the diffusion and transport theories and their limitations. Most of the problems encountered in regard to criticality involve fissile materials in simple or multiple assemblies. These entail the use of methods of calculation based on different principles. There are approximate methods of calculation, but very often, for economic reasons or with a view to practical application, a high degree of accuracy is required in determining the reactivity of the assemblies in question, and the methods based on the Monte Carlo principle are then the most valid. When these methods are used, accuracy is linked with the calculation time, so that the usefulness of the codes derives from their speed. With a view to carrying out the work in the best conditions, depending on the geometry and the nature of the materials involved, various codes must be used. Four principal codes are described, as are their variants; some typical possibilities and certain fundamental results are presented. Finally the accuracies of the various methods are compared. (author)
Kohu, Mojmír; Rožnovský, Jaroslav; Knozová, Grazyna
2014-09-01
Information about water evaporation is essential for the calculation of water balance. Evaporation, however, is a very complex physical process and it is therefore difficult to quantify. Evaporation measurements from the weather station network of the Czech Hydrometeorological Institute between 1968 and 2011 were performed using the evaporimeter GGI-3000. Evaporation was calculated using modified standard method based on FAO. The aim of the article was to compare the measured values and calculations. It has been found that the evaporation values from water surface calculated using the empirical equation are usually higher than the measured values by on average 0.8 mm, in extreme cases even 6.9 mm. The measured data shows higher variability than the calculated values, which means that correlations between series are not strong, the correlation coefficient being 0.7. Nevertheless the findings can be used for homogenization of series measured by the GGI-3000 evaporimeter.
Solar particle events observed at Mars: dosimetry measurements andmodel calculations
Energy Technology Data Exchange (ETDEWEB)
Cleghorn, Timothy F.; Saganti, Premkumar; Zeitlin, Cary J.; Cucinotta, Francis A.
2004-12-01
During the period from March 13, 2002 to mid-September, 2002, six solar particle events (SPE) were observed by the MARIE instrument onboard the Odyssey Spacecraft in Martian Orbit. These events were observed also by the GOES 8 satellite in Earth orbit, and thus represent the first time that the same SPE have been observed at these separate locations. The characteristics of these SPE are examined, given that the active regions of the solar disc from which the event originated can usually be identified. The dose rates at Martian orbit are calculated, both for the galactic and solar components of the ionizing particle radiation environment. The dose rates due to galactic cosmic rays (GCR) agree well with the HZETRN model calculations.
Comparison of methods for calculating rectal dose after 125I prostate brachytherapy implants
International Nuclear Information System (INIS)
Purpose: To compare several different methods of calculating the rectal dose and examine how accurately they represent rectal dose surface area measurements and, also, their practicality for routine use. Methods and Materials: This study comprised 55 patients, randomly selected from 295 prostate brachytherapy patients implanted at the Vancouver Cancer Center between 1998 and 2000. All implants used a nonuniform loading of 0.33 mCi (NIST-99) 125I seeds and a prescribed dose of 144 Gy. Pelvic CT scans were obtained for each patient ∼30 days after implantation. For the purposes of calculating the rectal dose, several structures were contoured on the CT images: (1) a 1-mm-thick anterior rectal wall, (2) the anterior half rectum, and (3) the whole rectum. Point doses were also obtained along the anterior rectal surface. The thin wall contour provided a surrogate for a dose-surface histogram (DSH) and was our reference standard rectal dose measurement. Alternate rectal dose measurements (volume, surface area, and length of rectum receiving a dose of interest [DOI] of ≥144 Gy and 216 Gy, as well as point dose measures) were calculated using several methods (VariSeed software) and compared with the surrogate DSH measure (SADOI). Results: The best correlation with SA144Gy was the dose volumes (whole or anterior half rectum) (R = 0.949). The length of rectum receiving ≥144 Gy also correlated well with SA144Gy (R ≥0.898). Point dose measures, such as the average and maximal anterior dose, correlated poorly with SA144Gy (R ≤0.649). The 216-Gy measurements supported these results. In addition, dose-volume measurements were the most practical (∼6 min/patient), with our surrogate DSH the least practical (∼20 min/patient). Conclusion: Dose-volume measurements for the whole or anterior half rectum, because they were the most practical measures and best represented the DSH measurements, should be considered a standard method of reporting the rectal dose when
Measurement and calculation of the neutron flux distribution in the RP-10 reactor
International Nuclear Information System (INIS)
In this work implementing experimental methods are implemented for easy reproduction for measuring the spatial distribution or thermal neutron flux in the RP-10 reactor core. Using two measuring methods: the passive and the active ones. In the passive method was used the activation technique using foils such as gold, manganese, and indium. These were irradiated in the reactor core and treated through the Westcott's formalism. In the active method was used the Self Powered Neutron Detectors (SPNs) for which was necessary to condition the detectors response for the data acquisition. The knowledge of the spatial distribution of RP-10 reactor neutrons flux will contribute in the understanding of other interesting parameters of reactor physics such as power density, reactivity, buckling, etc.. Wish knowledge is important for reactor operation. Fuel burnup calculations as well as others related to safety. (author)
Directory of Open Access Journals (Sweden)
Seied R Mahdavi
2012-01-01
Full Text Available Aims: The objective of this study is to evaluate the accuracy of a treatment planning system (TPS for calculating the dose distribution parameters in conformal fields (CF. Dosimetric parameters of CF′s were compared between measurement, Monte Carlo simulation (MCNP4C and TPS calculation. Materials and Methods: Field analyzer water phantom was used for obtaining percentage depth dose (PDD curves and beam profiles (BP of different conformal fields. MCNP4C was used to model conformal fields dose specification factors and head of linear accelerator varian model 2100C/D. Results: Results showed that the distance to agreement (DTA and dose difference (DD of our findings were well within the acceptance criteria of 3 mm and 3%, respectively. Conclusions: According to this study it can be revealed that TPS using equivalent tissue air ratio calculation method is still convenient for dose prediction in non small conformal fields normally used in prostate radiotherapy. It was also showed that, since there is a close correlation with Monte Carlo simulation, measurements and TPS, Monte Carlo can be further confirmed for implementation and calculation dose distribution in non standard and complex conformal irradiation field for treatment planning systems.
Institute of Scientific and Technical Information of China (English)
Hong Tang; Xiaogang Sun; Guibin Yuan
2007-01-01
In total light scattering particle sizing technique, the relationship among Sauter mean diameter D32, mean extinction efficiency Q, and particle size distribution function is studied in order to inverse the mean diameter and particle size distribution simply. We propose a method which utilizes the mean extinction efficiency ratio at only two selected wavelengths to solve D32 and then to inverse the particle size distribution associated with (Q) and D32. Numerical simulation results show that the particle size distribution is inversed accurately with this method, and the number of wavelengths used is reduced to the greatest extent in the measurement range. The calculation method has the advantages of simplicity and rapidness.
DEFF Research Database (Denmark)
Jeong, Cheol-Ho; Ih, Jeong-Guon; Rindel, Jens Holger
The phased beam tracing method (PBTM) is a technique which can calculate the pressure impulse response instead of energy impulse response, by taking the phase information into account. Inclusion of the phase information can extend the application of beam tracing technique to the mid frequency range...... in spite of the fact that the usual assumptions of geometric acoustics still hold. In the calculation of pressure impulse response, it is essential to have the reflection characteristics of the surfaces in the enclosed space. There is a method to obtain the reflection coefficient of the surface using...... the measured surface impedance. However, it is not always possible to get the measured impedance data of the surface, so that a practical way of getting reflection characteristics is needed. Generally, in the architectural acoustics field, the absorption coefficients have been employed in the...
International Nuclear Information System (INIS)
were investigated using the cluster fuel bundles of a heavy water reactor. Black and grey Dancoff factors for symmetrically different pin positions of various cluster fuel bundles were calculated by G-DANCOFF. The calculated Dancoff factors were applied to the criticality calculation using the WIMSD code. The concept of an equivalent Dancoff factor was introduced to use the grey Dancoff factor in the resonance calculation. The equivalent Dancoff factor is derived from an equivalence relation between a rational form's fuel collision probability based on the black Dancoff factor and an exact fuel collision probability based on the grey Dancoff factor. The equivalent Dancoff factor produces an exact fuel collision probability and can be used in the resonance calculation just as the traditional black Dancoff factor. A cluster is divided into inner and outer regions for the criticality calculation in the WIMSD code. WIMSD determines the outer resonance integral to preserve the cluster-average one without calculating the outer Dancoff factor directly. Calculated black and equivalent Dancoff factors by G-DANCOFF for each fuel pin in the cluster were grouped into inner and outer Dancoff factors to apply them to the WIMSD code. A new method was suggested for the calculation of the outer resonance integral based on the calculated outer Dancoff factor by Monte Carlo method. Criticality calculations were performed for critical experiments and CANDU37 and CANFLEX fuels of the Canadian heavy water reactor. Two-dimensional collision probability method with 69-group cross sections based on ENDF/B-VI was used in WIMSD calculation. In the benchmark calculations for the critical experiments, measured bucklings were used to calculate the effective multiplication factor (keff). The equivalent Dancoff factor improved keff with a difference about 1∼4mk compared with that based on the black Dancoff factors calculated by collision probability or Monte Carlo methods. Normal and void
Energy Labelling of Glazings and Windows in Denmark: Calculated and Measured Values
DEFF Research Database (Denmark)
Duer, Karsten; Svendsen, Svend; Mogensen, Morten Møller;
2002-01-01
The influence of windows on the energy consumption in buildings is well known and in order to encourage the development and the appropriate use of high performance glazings and windows in Denmark, an Energy Labelling and Rating system is being developed. During this work a need for establishing a...... common and well-defined method to characterise the performance of glazings and windows on the Danish market has been recognised. This paper gives a short description of the Danish Energy Labelling and Rating system for glazings and windows, which was put into operation during 2000. Furthermore the...... results of a comparison between measured and calculated thermal transmittance for five different window types are given. The calculations on the glazing part have been performed in five different programmes (WIS, WINDOW, VISION, CALUMEN and GLAD99). The calculations on the frame part have been performed...
Free phenytoin assessment in patients: measured versus calculated blood serum levels.
Tobler, Andrea; Hösli, Raphael; Mühlebach, Stefan; Huber, Andreas
2016-04-01
Background Total serum drug levels are routinely determined for the therapeutic drug monitoring of selected, difficult-to-dose drugs. For some of these drugs, however, knowledge of the free fraction is necessary to adapt correct dosing. Phenytoin, with its non-linear pharmacokinetics, >90 % albumin binding and slow elimination rate, is such a drug requiring individualization in patients, especially if rapid intravenous loading and subsequent dose adaptation is needed. In a prior long-term investigation, we showed the excellent performance of pharmacy-assisted Bayesian forecasting support for optimal dosing in hospitalized patients treated with phenytoin. In a subgroup analysis, we evaluated the suitability of the Sheiner-Tozer algorithm to calculate the free phenytoin fraction in hypoalbuminemic patients. Objective To test the usefulness of the Sheiner-Tozer algorithm for the correct estimation of the free phenytoin concentrations in hospitalized patients. Setting A Swiss tertiary care hospital. Method Free phenytoin plasma concentration was calculated from total phenytoin concentration in hypoalbuminemic patients and compared with the measured free phenytoin. The patients were separated into a low (35 ≤ albumin ≥ 25 g/L) and a very low group (albumin <25 g/L) for comparing and statistically analyzing the calculated and the measured free phenytoin concentration. Main outcome measures Calculated and the measured free phenytoin concentration. Results The calculated (1.2 mg/L (SD = 0.7) and the measured (1.1 mg/L (SD = 0.5) free phenytoin concentration correlated. The mean difference in the low and the very low albumin group was: 0.10 mg/L (SD = 1.4) (n = 11) and 0.13 mg/L (SD = 0.24) (n = 12), respectively. Although the variability of the data could be a bias, no statistically significant difference between the groups was found: t test (p = 0.78), the Passing-Bablok regression, the Spearman's rank correlation coefficient of r = 0
Precise measurement and calculation of 238U neutron transmissions
International Nuclear Information System (INIS)
The total neutron cross section of 238U has been measured above 0.5 eV in precise transmission experiments and results are compared with ENDF/B-IV. Emphasis has been on measuring transmissions through thick samples in order to obtain accurate total cross sections in the potential-resonance interference regions between resonances. 4 figures, 1 table
Directory of Open Access Journals (Sweden)
A. I. Antonov
2012-02-01
Full Text Available Problem statement. Power objects (heat and power plants, district heat plants, and boiler plantsare located within the precincts of the settlements and are sources of elevated noise levels. Thereuponthere is a necessity of estimation of a noise conditions in the premises of thermal power stationsand in the territories adjoining to them. The process of formation of noise conditions in thethermal power station premises is a difficult multiple process, which requires sophisticated mathematicalmodels for its description. The existing methods do not provide obligatory accuracy ofcalculations. The development of the new methods is required.Results. The new combined method of noise calculation in industrial premises of the thermalpower stations is proposed. The method is based on the principles of division of glassy and diffusivecomponents of the reflected energy and their calculation, accordingly, with the help of a methodof tracing and a statistical energy method. The total condensation of sound energy in imputedpoints is determined by the power summation of all the components. For the method implementationa computer model is elaborated.Conclusions. The method proposed and the computer model of its implementation provide the solutionof problems of noise estimation in the premises of the thermal power stations and in the adjoiningareas. The accuracy of the calculations is sufficient for an objective estimation of noise andfor development of the measures on its reduction.
Methods for calculating SEU rates for bipolar and NMOS circuits
McNulty, P. J.; Abdel-Kader, W. G.; Bisgrove, J. M.
1985-12-01
Computer codes developed at Clarkson for simulating charge generation by proton-induced nuclear reactions in well-defined silicon microstructures can be used to calculate SEU rates for specific devices when the critical charge and the dimensions of all SEU sensitive junctions on the device are known, provided one can estimate the contribution from externally-generated charge which enters the sensitive junction by drift and diffusion. Calculations for two important bipolar devices, the AMD 2901B bit slice and the Fairchild 93L422 RAM, for which the dimensions of the sensitive volumes were estimated from available heavy-ion test data, have been found to be in agreement with experimental data. Circuit data for the Intel 2164A, an alpha sensitive dRAM, was provided by the manufacturer. Calculations based on crude assumptions regarding which nuclear recoils and which alphas trigger upsets in the 2164A were found to agree with experimental data.
International Nuclear Information System (INIS)
This paper presents high accuracy tritium production rate measurement results compared with calculations using the MCNPX Monte Carlo particle transport code. The experimental results are regarded as reference values for a new passive technique based on the secondary charged particle activation method developed for measuring the tritium production rate in the test blanket modules of the ITER Tokamak. The 16O(t,n)18F reaction, which is one of the possible tritium monitor reactions, was also extensively investigated, and the experimentally determined reaction rates were compared with simulations. Li2CO3 solution was filled and sealed into quartz ampoules which were irradiated in the Training Reactor of the Budapest University of Technology and Economics. The amount of 18F was determined using γ-spectroscopy. Then the precise tritium measurements were carried out in the Hertelendi Laboratory of Environmental Studies using the 3H–3He ingrowth method, where the 3He produced during the storage time is measured by a static noble gas mass spectrometer (VG-5400). The HT/HTO ratio in the irradiated aqueous solutions was found to be 0.1323±0.0034. Based on the comparison of the measurements and the simulations it was pointed out that the model calculations underestimate the reaction rate of both the 6Li(n,t)α and the 16O(t,n)18F reactions by 5–10% and 15%, respectively. -- Highlights: ► Tritium measurements for verifying the 6Li6(n, t)α reaction rate calculated by MCNPX. ► The HT/HTO ratio was determined in the neutron irradiated aqueous solution of Li2CO3. ► The reaction rate of 16O(t,n)18F was measured in thermal neutron spectrum
Automated Methods of Corrosion Measurements
DEFF Research Database (Denmark)
Andersen, Jens Enevold Thaulov
. Mechanical control, recording, and data processing must therefore be automated to a high level of precision and reliability. These general techniques and the apparatus involved have been described extensively. The automated methods of such high-resolution microscopy coordinated with computerized...
Calculation of VPP basing on functional analyzing method
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
VPP can be used to deter mine the maxi mumvelocities of a sailboard at various sailing-routes,byestablishing the forces and moments balance-equa-tions on the sail and board in accordance with theprinciple of the maxi mal drive-force.Selectingroute is the most i mportant issue in upwind-sailing,and VPP calculations could provide the basis for de-ter mining the opti mal routes.VPP calculation of the sailboard perfor mance isa complex and difficult research task,and there arefew projects in this research-field...
A method for measuring contact pressures instantaneously in articular joints.
Inaba, H; Arai, M
1989-01-01
A method whereby instrumented pipes are inserted part of the way into articular cartilage from the underlying subchondral bone has been developed for measuring instantaneous contact pressures acting within articular joints. Contact pressures developed between two specimens cut from fresh cadaveric knee joints were measured with this technique and then subsequently with pressure-sensitive paper. Average contact pressures (load/contact area) were also calculated. Comparisons of the three sets of data show that contact pressures measured with the pressure pipe system are linearly related (p less than 0.001) to both the contact pressures measured with the pressure-sensitive paper and the calculated average contact pressures. PMID:2625431
Comparison of hardenability calculation methods of the heat-treatable constructional steels
International Nuclear Information System (INIS)
Evaluation has been made of the consistency of calculation of the hardenability curves of the selected heat-treatable alloyed constructional steels with the experimental data. The study has been conducted basing on the analysis of present state of knowledge on hardenability calculation employing the neural network methods. Several calculation examples and comparison of the consistency of calculation methods employed are included. (author)
The correlated-k method and related methods for broadband radiation calculations
International Nuclear Information System (INIS)
The fundamentals of radiation calculations in planetary atmospheres have been known for a long time, but the practical problems of calculating radiation over a broad spectral range both efficiently and accurately remain an area of active research. The Goody et al. paper of 1989 established a milestone in that long effort. Goody et al. highlighted attempts to formulate the problem in terms of a few absorption coefficients that could represent typically tens of thousands of coefficients in a rigorous line-by-line calculation. Here we provide a brief background, point out that the correlated-k method is a special case of a broader spectral mapping concept, and mention some new ideas that have emerged recently.
Methods for measurement of durability parameters
DEFF Research Database (Denmark)
Hansen, Ernst Jan De Place
1996-01-01
Present selected methods for measurement of durabilty parameters relating to chlorides, corrosion, moisture and freeze-thaw, primarly on concrete. Advantages and drawbacks of the different methods are included.......Present selected methods for measurement of durabilty parameters relating to chlorides, corrosion, moisture and freeze-thaw, primarly on concrete. Advantages and drawbacks of the different methods are included....
Comparison of different methods for thoron progeny measurement
International Nuclear Information System (INIS)
Four popular methods for thoron progeny measurement were discussed, including the aspects of detector,principle, precondition, calculation advantages and disadvantages. Comparison experiments were made in mine and houses with high background in Yunnan Province. Since indoor thoron progeny changes with time obviously and with no rule, α track method is recommended in the area of radiation protection for environmental detection and assessment. (authors)
Heat Conduction Analysis in a Tissue Phantom Calculated by FDTD and HCE Method
Endoh, Nobuyuki; Tsuchiya, Takenobu; Saito, Yoshikazu; Ishizeki, Takahiro
2005-03-01
In order to study hyperthermia in tissue, it is important to predict accurately the heat distribution. This paper describes a preliminary study of the comparison between simulation and experiment for heat conduction in a simple tissue phantom. Since it is well known that the heat increase in tissue depends on the sound intensity and the absorption coefficient, the sound pressure distribution is calculated using a Finite Difference Time Domain (FDTD) method. The thermal diffusion profile in tissue generated by the energy of the sound pulse is also simulated using the Heat Conduction Equation (HCE) method. The calculation area is 100 × 40 [mm]. The simple tissue phantom is made of agar, water and graphite. The phantom whose attenuation coefficient is 1.1 dB/cm/MHz is placed in a temperature controlled water bath. This is kept at 37 degrees [C] while sound pulses of 1 MHz are emitted over 10 minutes. Temperatures at six points on the acoustic axis are measured in the phantom. The calculation and experiment results are compared to confirm the accuracy of the proposed method. As a result, the calculation results show the validity of the combined FDTD-HCE method for thermal conduction analysis.
Heat Conduction Analysis in a Tissue Phantom Calculated by FDTD and HCE Method
International Nuclear Information System (INIS)
In order to study hyperthermia in tissue, it is important to predict accurately the heat distribution. This paper describes a preliminary study of the comparison between simulation and experiment for heat conduction in a simple tissue phantom. Since it is well known that the heat increase in tissue depends on the sound intensity and the absorption coefficient, the sound pressure distribution is calculated using a Finite Difference Time Domain (FDTD) method. The thermal diffusion profile in tissue generated by the energy of the sound pulse is also simulated using the Heat Conduction Equation (HCE) method. The calculation area is 100 x 40 [mm]. The simple tissue phantom is made of agar, water and graphite. The phantom whose attenuation coefficient is 1.1 dB/cm/MHz is placed in a temperature controlled water bath. This is kept at 37 deg. [C] while sound pulses of 1 MHz are emitted over 10 minutes. Temperatures at six points on the acoustic axis are measured in the phantom. The calculation and experiment results are compared to confirm the accuracy of the proposed method. As a result, the calculation results show the validity of the combined FDTD-HCE method for thermal conduction analysis
Comparison between ASHRAE and ISO thermal transmittance calculation methods
DEFF Research Database (Denmark)
Blanusa, Petar; Goss, William P.; Roth, Hartwig;
2007-01-01
The intent of this paper is to describe and compare the two different two-dimensional frame/spacer heat transfer calculation methodologies used in North America (FRAME [EEL. The FRAMEplus Toolkit for Heat Transfer Assessment of Building Components, Version 3.0, Enermodal Engineering, Kichener, On...
International Nuclear Information System (INIS)
The tip deflections of wind turbine blades should be monitored continuously to prevent catastrophic failures of wind turbine power plants caused by blades hitting the tower. In this paper, a calculation method for wind turbine blade tip deflection is proposed using a finite difference method based on arbitrary beam bending and moment theory using measured strains. The blade strains were measured using fiber optic Bragg grating sensors. In order to confirm this method, a 100 kW composite wind turbine blade was manufactured with epoxy molded fiber optic Bragg grating (FBG) sensors installed in the shear web of the blade. A number of these sensors, normal FBG probes, were fabricated to only measure strains and the other sensors, temperature compensated FBG probes, were prepared to also measure strain and temperature. Because the output signals of FBG sensors are dependent on strains as well as temperatures, the sensor output signals should be compensated by the temperatures to obtain accurate strains. These FBG sensors were attached on the lower and upper parts of the web at one meter intervals throughout the entire length of the blade. To evaluate the measurement accuracy of the FBG sensors, conventional electrical strain gauges were also bonded onto the surface of the web beside each FBG sensor. By performing a static load test of the blade, the calculated tip deflection of the blade was well determined within an average error of 2.25%. (paper)
Measuring methods of matrix diffusion
International Nuclear Information System (INIS)
In Finland the spent nuclear fuel is planned to be disposed of at large depths in crystalline bedrock. The radionuclides which are dissolved in the groundwater may be able to diffuse into the micropores of the porous rock matrix and thus be withdrawn from the flowing water in the fractures. This phenomenon is called matrix diffusion. A review over matrix diffusion is presented in the study. The main interest is directed to the diffusion of non-sorbing species. The review covers diffusion experiments and measurements of porosity, pore size, specific surface area and water permeability
Flow measurement by ultrasonic method
International Nuclear Information System (INIS)
An Ultrasonic Flow Meter (USFM) wasdeveloped to measure flow velocity of high temperature fluid in a pipe. To protect ultrasonic transducers from high temperature, guide rods were used. From the study on mechanical structure and acoustic property, the guide rod and the electronic circuit were improved to have capabilities of temperature compensation, quick response, high accuracy and not to be easily disturbed by bubbles contained in the fluid flow. Using a water flow loop, the test results proved the accuracy of +-1.0 percent and response time of 10 m sec
Luna, D.; Alexander, P.; de la Torre, A.
2013-09-01
The application of the Global Positioning System (GPS) radio occultation (RO) method to the atmosphere enables the determination of height profiles of temperature, among other variables. From these measurements, gravity wave activity is usually quantified by calculating the potential energy through the integration of the ratio of perturbation and background temperatures between two given altitudes in each profile. The uncertainty in the estimation of wave activity depends on the systematic biases and random errors of the measured temperature, but also on additional factors like the selected vertical integration layer and the separation method between background and perturbation temperatures. In this study, the contributions of different parameters and variables to the uncertainty in the calculation of gravity wave potential energy in the lower stratosphere are investigated and quantified. In particular, a Monte Carlo method is used to evaluate the uncertainty that results from different GPS RO temperature error distributions. In addition, our analysis shows that RO data above 30 km height becomes dubious for gravity waves potential energy calculations.
Classification of methods for annual energy harvesting calculations of photovoltaic generators
International Nuclear Information System (INIS)
Highlights: • The paper presents a novel classification of methods for annual energy harvesting calculation of grid-connected PV systems. • The methods are classified in direct and indirect methods. • Direct methods directly calculate the energy. Indirect methods calculate the energy from the power. • The classification can help the PV professionals in order to choose the most suitable method for each application. - Abstract: Estimating the energy provided by the generators of grid-connected photovoltaic systems is important in order to analyze their economic viability and supervise their operation. The energy harvesting calculation of a photovoltaic generator is not trivial; there are a lot of methods for this calculation. The aim of this paper is to develop a novel classification of methods for annual energy harvesting calculation of a generator of a grid-connected photovoltaic system. The methods are classified in two groups: (1) those that indirectly calculate the energy, i.e. they first calculate the power and from this, they calculate the energy, and (2) those that directly calculate the energy. Furthermore, the indirect methods are grouped in two categories: those that first calculate the I–V curve of the generator and from this, they calculate the power, and those that directly calculate the power. The study has shown that the existing methods differ in simplicity and accuracy, so that the proposed classification is useful in order to choose the most suitable method for each specific application
On-field validation of a seasonal performance calculation method for chillers in buildings
International Nuclear Information System (INIS)
Highlights: • An accurate method for chiller part load performance calculation is proposed. • The developed method requires the same input data as the one in current EN 14825. • Hourly predicted values of EER are validated against on-field measurements. • On-field measurements were taken in very different HVAC plants. • On-field measurement quality is checked through an accurate uncertainty analysis. - Abstract: In the last years the importance of part load conditions in the estimation of chiller performance in real world operation has been completely acknowledged. As a matter of fact, chillers are sized for peak loads, so they usually run under part load conditions, far from the full load ones, taken as references in catalogues. Some methods for these calculations already exist, both in Standards and in building energy simulation programs, but they lack an extensive validation in actual HVAC systems. In this regard, the present paper compares the chiller performance estimated via the calculation method contained in Standard EN 14825 against monitored data taken along an entire cooling season, both in a small HVAC plant and in a large one. In the present paper a variation of the calculation method contained in Standard EN 14825 is used indeed. In particular, in this variation of the EN 14825 calculation method, the interpolation between the values of EER rated under part load conditions is performed by means of intermediate parameter Z, equal to the ratio of the electrical power consumption under part load conditions to the electrical power consumption under full load conditions. This interpolation method allows the HVAC designer to draw more reliable profiles of PLF (Part Load Factor) versus the capacity ratio (CR), in order to increase the accuracy in performance prediction under part load conditions. As a matter of fact, this interpolation method allows the HVAC designer to achieve a better estimation of the EER at low values of the part load ratio
International Nuclear Information System (INIS)
The measurement of cerebral blood flow (CBF) by the extracranial detection of the radioactivity of 133Xe injected into an internal carotid artery has proved to be of considerable value for the investigation of cerebral circulation in conscious rabbits. Methods are described for calculating CBF from the curves of clearance of 133Xe, and include exponential analysis (two-component model), initial slope, and stochastic method. The different methods of curve analysis were compared in order to evaluate the fitness with the theoretical model. The initial slope and stochastic methods, compared with the biexponential model, underestimate the CBF by 35% and 46% respectively. Furthermore, the validity of recording the clearance curve for 10 min was tested by comparing these CBF values with those obtained from the whole curve. CBF values calculated with the shortened procedure are overestimated by 17%. A correlation exists between the ''10 min'' CBF values and the CBF calculated from the whole curve; in spite of that, the values are not accurate for limited animal populations or for single animals. The extent of the two main compartments into which the CBF is divided was also measured. There is no correlation between CBF values and the extent of the relative compartment. This fact suggests that these two parameters correspond to different biological entities
Pion-Induced Fission of 209Bi and 119Sn:. Measurements, Calculations, Analyses and Comparison
Rana, Mukhtar Ahmed; Sher, Gul; Manzoor, Shahid; Shehzad, M. I.
Cross-sections for the π--induced fission of 209Bi and 119Sn have been measured using the most sensitive CR-39 solid-state nuclear track detector. In experiments, target-detector stacks were exposed to negative pions of energy 500, 672, 1068, and 1665 MeV at the Brookhaven National Laboratory, USA. An important aspect of the present paper is the comparison of pion-induced fission fragment spectra of above mentioned nuclei with the spontaneous fission fragment spectra of 252Cf. This comparison is made in terms of fission fragment track lengths in the CR-39 detectors. Measurement results are compared with calculations of Monte Carlo and statistical weight functions methods using the computer code CEM95. Agreement between measurements and calculations is fairly good for 209Bi target nuclei whereas it is indigent for the case of 119Sn. The possibilities of the trustworthy calculations, using the computer code CEM95, comparable with measurements of pion-induced fission in intermediate and heavy nuclei are explored by employing various systematics available in the code. Energy dependence of pion-induced fission in 119Sn and 209Bi is analyzed employing a newly defined parameter geometric-size-normalized fission cross-section (χfg). It is found that the collective nuclear excitations, which may lead to fission, become more probable for both 209Bi and 119Sn nuclei with increasing energy of negative pions from 500 to 1665 MeV.
Analysis of some splitting and roulette algorithms in shield calculations by the Monte Carlo method
International Nuclear Information System (INIS)
Different schemes of using the splitting and roulette methods in calculation of radiation transport in nuclear facility shields by the Monte Carlo method are considered. Efficiency of the considered schemes is estimated on the example of test calculations
Low energy houses - measured and calculated; Lavenergihuse - maalt og beregnet
Energy Technology Data Exchange (ETDEWEB)
Schultz, J.M. [BYG-DTU, Lyngby (Denmark); Engelund Thomsen, K. [By og Byg, Hoersholm (Denmark)
2002-07-01
This article summarizes measurement results from 7 low energy houses build in 6 different countries in connection with the IEA Task 13 project: Advanced Solar Low Energy Buildings. The objective of the project was to design and build low energy houses with a total energy consumption of approximately 25% of the energy consumption level in standard houses. Each individual participating country has been responsible for developing a measuring programme for documentation of the house's energy consumption, indoor climate, etc. The measurement results from the 7 low energy houses show that it is possible to reduce the total energy consumption with 60% compared with standard houses. Furthermore, it has been proven that problems with high temperature and bad indoor climate in highly insulated houses can be solved, if solutions are sought in the planning phase. (BA)
Evaluation of Monte Carlo Codes Regarding the Calculated Detector Response Function in NDP Method
International Nuclear Information System (INIS)
The basis of the NDP is the irradiation of a sample with a thermal or cold neutron beam and the subsequent release of charged particles due to neutron-induced exoergic charged particle reactions. Neutrons interact with the nuclei of elements and release mono-energetic charged particles, e.g. alpha particles or protons, and recoil atoms. Depth profile of the analyzed element can be obtained by making a linear transformation of the measured energy spectrum by using the stopping power of the sample material. A few micrometer of the material can be analyzed nondestructively, and on the order of 10nm depth resolution can be obtained depending on the material type with NDP method. In the NDP method, the one first steps of the analytical process is a channel-energy calibration. This calibration is normally made with the experimental measurement of NIST Standard Reference Material sample (SRM-93a). In this study, some Monte Carlo (MC) codes were tried to calculate the Si detector response function when this detector accounted the energy charges particles emitting from an analytical sample. In addition, these MC codes were also tried to calculate the depth distributions of some light elements (10B, 3He, 6Li, etc.) in SRM-93a and SRM-2137 samples. These calculated profiles were compared with the experimental profiles and SIMS profiles. In this study, some popular MC neutron transport codes are tried and tested to calculate the detector response function in the NDP method. The simulations were modeled based on the real CN-NDP system which is a part of Cold Neutron Activation Station (CONAS) at HANARO (KAERI). The MC simulations are very successful at predicting the alpha peaks in the measured energy spectrum. The net area difference between the measured and predicted alpha peaks are less than 1%. A possible explanation might be bad cross section data set usage in the MC codes for the transport of low energetic lithium atoms inside the silicon substrate
International Nuclear Information System (INIS)
In the design of the reactor room for a fusion reactor, the cost of the room strongly depends on the thickness of the roof because the area of the roof is generally large. The roof thickness is mostly determined by the requirement to reduce the skyshine dose rate level at the site boundary below the assigned value. Therefore the accurate evaluation of the skyshine dose becomes important for the design of the reactor room. Skyshine dose for a D-T fusion reactor has been evaluated by a number of researchers but the agreement is not so good. In this report, the first collision source is used with two-dimensional SN transport method to form DOT3.5-GRTUNCL-DOT3.5 coupled calculation flow. The validity of the methodology was first shown by calculating the skyshine dose from a 14 MeV neutron source and comparing the calculated results with the measured results. This methodology was then used to calculate the skyshine dose for the Fusion Experimental Reactor (FER). The calculated results were compared with those from several other methods to clarify the mutual difference. (author)
Open Photoacoustic Cell for Blood Sugar Measurement: Numerical Calculation of Frequency Response
Baumann, Bernd; Teschner, Mark
2015-01-01
A new approach for continuous and non-invasive monitoring of the glucose concentration in human epidermis has been suggested recently. This method is based on photoacoustic (PA) analysis of human interstitial fluid. The measurement can be performed in vitro and in vivo and, therefore, may form the basis for a non-invasive monitoring of the blood sugar level for diabetes patients. It requires a windowless PA cell with an additional opening that is pressed onto the human skin. Since signals are weak, advantage is taken of acoustic resonances of the cell. Recently, a numerical approach based on the Finite Element (FE) Method has been successfully used for the calculation of the frequency response function of closed PA cells. This method has now been adapted to obtain the frequency response of the open cell. Despite the fact that loss due to sound radiation at the opening is not included, fairly good accordance with measurement is achieved.
Calculations of NMR chemical shifts with APW-based methods
Laskowski, Robert; Blaha, Peter
2012-01-01
We present a full potential, all electron augmented plane wave (APW) implementation of first-principles calculations of NMR chemical shifts. In order to obtain the induced current we follow a perturbation approach [Pickard and Mauri, Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.63.245101 63, 245101 (2001)] and extended the common APW + local orbital (LO) basis by several LOs at higher energies. The calculated all-electron current is represented in traditional APW manner as Fourier series in the interstitial region and with a spherical harmonics representation inside the nonoverlapping atomic spheres. The current is integrated using a “pseudocharge” technique. The implementation is validated by comparison of the computed chemical shifts with some “exact” results for spherical atoms and for a set of solids and molecules with available published data.
Calculation of gamma-ray families by Monte Carlo method
International Nuclear Information System (INIS)
Extensive Monte Carlo calculation on gamma-ray families was carried out under appropriate model parameters which are currently used in high energy cosmic ray phenomenology. Characteristics of gamma-ray families are systematically investigated by the comparison of calculated results with experimental data obtained at mountain altitudes. The main point of discussion is devoted to examine the validity of Feynman scaling in the fragmentation region of the multiple meson production. It is concluded that experimental data cannot be reproduced under the assumption of scaling law when primary cosmic rays are dominated by protons. Other possibilities on primary composition and increase of interaction cross section are also examined. These assumptions are consistent with experimental data only when we introduce intense dominance of heavy primaries in E0>1015 eV region and very strong increase of interaction cross section (say sigma varies as Esub(0)sup(0.06)) simultaneously
Multi CPU clusters and calculations by molecular dynamics method
International Nuclear Information System (INIS)
The technical characteristics of multi CPU (Central Processor Unit) clusters in Institute of Ion-Plasma and Laser Technologies AS RUz and Institute of Mathematics and Information Technologies AS RUz are described. There is detail information about cluster s architecture, installed programs and their productivity for decision of molecular dynamics tasks. Molecular dynamics program packages GROMACS, OPENMX and AutoDock-4.2.3 are described. The results of calculations using these program packages are presented. (author)
Hargreaves and other reduced-set methods for calculating evapotranspiration
Shahidian, Shakib; Serralheiro, Ricardo; Serrano, João; Teixeira, José; Haie, Naim; Santos, Francisco
2012-01-01
Globally, irrigation is the main user of fresh water, and with the growing scarcity of this essential natural resource, it is becoming increasingly important to maximize efficiency of water usage. This implies proper management of irrigation and control of application depths in order to apply water effectively according to crop needs. Daily calculation of the Reference Potential Evapotranspiration (ETo) is an important tool in determining the water needs of different crops. The United Nations...
Cost Accounting Methods and Calculation Agricultural Products` Cost
Saule B. Spatayeva
2015-01-01
In the condition of the current market the effective manage of expenses and calculation accountancy of cost production in agriculture must be aimed to control for resources usage at any level of technology process and getting the accountancy database needed for gaining the management targets.The improving the technologies and set up aspects of business entity activity, taken place for the last decades, which caused a significant influence on condition and structure expenses but could not prov...
Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements
International Nuclear Information System (INIS)
Beta activity measurements were used as surrogate measurements of uranium mass in aerosol samples collected during the field testing phase of the Capstone Depleted Uranium (DU) Aerosol Study. These aerosol samples generated by the perforation of armored combat vehicles were used to characterize the depleted uranium (DU) source term for the subsequent human health risk assessment (HHRA) of Capstone aerosols. Establishing a calibration curve between beta activity measurements and uranium mass measurements is straightforward if the uranium isotopes are in equilibrium with their immediate short-lived, beta-emitting progeny. For DU samples collected during the Capstone study, it was determined that the equilibrium between the uranium isotopes and their immediate short lived, beta-emitting progeny had been disrupted when penetrators had perforated target vehicles. Adjustments were made to account for the disrupted equilibrium and for wall losses in the aerosol samplers. Correction factors for the disrupted equilibrium ranged from 0.16 to 1, and the wall loss correction factors ranged from 1 to 1.92
International Nuclear Information System (INIS)
Under the SR 2045 and SR 2045/1 projects the tests for applying the advanced potential drop method in recurrent inspections in nuclear power plants are continued. The project is chiefly aimed at optimising and improving the early detection of defects and flaws in piping systems during the customary periodic inspection. The potential drop method which has been refined for this purpose can preferably be applied as an additional alternative in places and under conditions where it is difficult for orthodox methods to detect and monitor defects and flaws in materials. As a non-destructive method, the potential drop method is almost unrivalled when it comes to continuously monitoring indications, findings and areas of the material for crack formation and crack growth (even at service temperatures). And here it was possible to achieve an appreciable success: A potential drop measuring field is now much faster to install than before thanks to the belts developed. This is of particular advantage in areas of increased radiation levels. Moreover, comparative calculations by means of the MAFIA Finite Difference Programme have proved that the calibration and interpretation of measured values obtained from ferrite/austenite weld joints, weld joints between components of different wall thickness and intricate structures can be considerably improved by such calculations. (orig.)
7 CFR 51.308 - Methods of sampling and calculation of percentages.
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Methods of sampling and calculation of percentages. 51..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Methods of Sampling and Calculation of Percentages § 51.308 Methods of sampling and calculation of percentages. (a) When the...
Directory of Open Access Journals (Sweden)
A. Yu. Zhuravlev
2016-04-01
network coefficients. When building the FM reversal model in parallel magnetic fields, the most accurate methods are the approximation ones that take into account not only the changes in values and over time, but also their derivatives. The development of computer hardware and software makes real the mathematical methods for calculating TC with significant change in ferromagnetic inductance, including the saturation areas. Herewith, it is important to search for approximating analytical expression that describes the dynamic limit hysteresis loop (HL. Practical value. The changes in the electrical parameters of the same TC were analysed using the classical and the new calculation methods, the difference made less than 10%. The work introduced some measures to increase operational noise immunity of TC.
Rousset, G; Charbonnier, F; Lepoutre, F.
1983-01-01
The calculation of the thermoelastic bending of thin plates shows that this effect can dominate the photoacoustic effect with thermally thick samples. An application of this calculation to thermal diffusivity measurements is given.
Institute of Scientific and Technical Information of China (English)
赵晓刚
2012-01-01
Combined with production practice, calculating methods of mixed oil quantity in the batch transportation product pipeline were mainly introduced as well as theoretical formula, corrected theoretical formula and empirical formula. Through example calculation, different formulae were compared. Then, factors to influence mixed oil quantity were analyzed, and measures to reduce mixed oil quantity were put forward.%结合生产实际,重点介绍了成品油顺序输送管道混油量的计算方法,包括理论公式、修正的理论公式以及经验公式,并进行了相应的实例计算,对各种计算公式进行的比较,分析了混油量的影响因素,提出了减少混油量的措施.
Transmission line icing measurement on photogrammetry method
Huang, Huan; Ma, Xiaohong; Zhao, Lijin; Du, Hao; Luo, Hong; Mao, Xianyin; Tang, Min; Liu, Yawen
2015-12-01
Icing thickness parameter is the basic data for power sector to make decision for icing accident prevention. In this paper, a transmission line icing measurement method is proposed. It used the photogrammetry method to realize icing parameters measurement through the integration of high resolution camera, laser range finder and inertial measurement unit. Compared with traditional icing measurement method, this method is flexible and is the effective supplement of the fixed icing detection terminal. And its high accuracy measurement guarantees the reliability of the icing thickness parameters.
Recently developed methods in neutral-particle transport calculations: overview
International Nuclear Information System (INIS)
It has become increasingly apparent that successful, general methods for the solution of the neutral particle transport equation involve a close connection between the spatial-discretization method used and the source-acceleration method chosen. The first form of the transport equation, angular discretization which is discrete ordinates is considered as well as spatial discretization based upon a mesh arrangement. Characteristic methods are considered briefly in the context of future, desirable developments. The ideal spatial-discretization method is described as having the following attributes: (1) positive-positive boundary data yields a positive angular flux within the mesh including its boundaries; (2) satisfies the particle balance equation over the mesh, that is, the method is conservative; (3) possesses the diffusion limit independent of spatial mesh size, that is, for a linearly isotropic flux assumption, the transport differencing reduces to a suitable diffusion equation differencing; (4) the method is unconditionally acceleratable, i.e., for each mesh size, the method is unconditionally convergent with a source iteration acceleration. It is doubtful that a single method possesses all these attributes for a general problem. Some commonly used methods are outlined and their computational performance and usefulness are compared; recommendations for future development are detailed, which include practical computational considerations
Methods for High Power EM Pulse Measurement
Directory of Open Access Journals (Sweden)
P. Fiala
2006-12-01
Full Text Available There are some suitable methods for the measurement of ultra-short solitary electromagnetic pulses that can be generated by high power pulsed generators. The measurement methods properties have to correspond to the fact whether we want to measure pulses of voltage, current or free-space electromagnetic wave. The need for specific measurement methods occurred by the development of high power microwave pulse generator. Applicable methods are presented in this paper. The method utilizing Faraday's induction law allows the measurement of generated current. For the same purpose the magneto-optic method can be utilized, with its advantages. For measurement of output microwave pulse of the generator the calorimetric method was designed and realized.
Pennec, Fabienne; Alzina, Arnaud; Tessier-Doyen, Nicolas; Naitali, Benoit; Smith, David S.
2012-11-01
This work is about the calculation of thermal conductivity of insulating building materials made from plant particles. To determine the type of raw materials, the particle sizes or the volume fractions of plant and binder, a tool dedicated to calculate the thermal conductivity of heterogeneous materials has been developped, using the discrete element method to generate the volume element and the finite element method to calculate the homogenized properties. A 3D optical scanner has been used to capture plant particle shapes and convert them into a cluster of discret elements. These aggregates are initially randomly distributed but without any overlap, and then fall down in a container due to the gravity force and collide with neighbour particles according to a velocity Verlet algorithm. Once the RVE is built, the geometry is exported in the open-source Salome-Meca platform to be meshed. The calculation of the effective thermal conductivity of the heterogeneous volume is then performed using a homogenization technique, based on an energy method. To validate the numerical tool, thermal conductivity measurements have been performed on sunflower pith aggregates and on packed beds of the same particles. The experimental values have been compared satisfactorily with a batch of numerical simulations.
International Nuclear Information System (INIS)
This work is about the calculation of thermal conductivity of insulating building materials made from plant particles. To determine the type of raw materials, the particle sizes or the volume fractions of plant and binder, a tool dedicated to calculate the thermal conductivity of heterogeneous materials has been developped, using the discrete element method to generate the volume element and the finite element method to calculate the homogenized properties. A 3D optical scanner has been used to capture plant particle shapes and convert them into a cluster of discret elements. These aggregates are initially randomly distributed but without any overlap, and then fall down in a container due to the gravity force and collide with neighbour particles according to a velocity Verlet algorithm. Once the RVE is built, the geometry is exported in the open-source Salome-Meca platform to be meshed. The calculation of the effective thermal conductivity of the heterogeneous volume is then performed using a homogenization technique, based on an energy method. To validate the numerical tool, thermal conductivity measurements have been performed on sunflower pith aggregates and on packed beds of the same particles. The experimental values have been compared satisfactorily with a batch of numerical simulations.
Directory of Open Access Journals (Sweden)
Safarini Osama
2012-01-01
Full Text Available An important task of operational management in oil and gas production is the control of fluid flow and technological objects of engineering network (EN. This paper proposed a method for diagnosis of fluid flow measurement and calibration operations. The method is based on the relationship between various parameters of the flow of Engineering Network. To calculate the actual flow rate on other parameters of the flow, such as pressure, temperature, and the parameters that determine the composition of the liquid (oil, it is proposed to use a neural network.
Inverse dispersion method for calculation of complex photonic band diagram and PT symmetry
Rybin, Mikhail V.; Limonov, Mikhail F.
2016-04-01
We suggest an inverse dispersion method for calculating a photonic band diagram for materials with arbitrary frequency-dependent dielectric functions. The method is able to calculate the complex wave vector for a given frequency by solving the eigenvalue problem with a non-Hermitian operator. The analogy with PT -symmetric Hamiltonians reveals that the operator corresponds to the momentum as a physical quantity, and the singularities at the band edges are related to the branch points and responses for the features on the band edges. The method is realized using a plane wave expansion technique for a two-dimensional periodic structure in the case of TE and TM polarizations. We illustrate the applicability of the method by the calculation of the photonic band diagrams of an infinite two-dimensional square lattice composed of dielectric cylinders using the measured frequency-dependent dielectric functions of different materials (amorphous hydrogenated carbon, silicon, and chalcogenide glass). We show that the method allows one to distinguish unambiguously between Bragg and Mie gaps in the spectra.
Single-Sweep Methods for Free Energy Calculations
Maragliano, Luca; Vanden-Eijnden, Eric
2007-01-01
A simple, efficient, and accurate method is proposed to map multi-dimensional free energy landscapes. The method combines the temperature-accelerated molecular dynamics (TAMD) proposed in [Maragliano & Vanden-Eijnden, Chem. Phys. Lett. 426, 168 (2006)] with a variational reconstruction method using radial-basis functions for the representation of the free energy. TAMD is used to rapidly sweep through the important regions of the free energy landscape and compute the gradient of the free energ...
Methods in pharmacology: measurement of cardiac output
Geerts, Bart F; Aarts, Leon P; Jansen, Jos R.
2011-01-01
Many methods of cardiac output measurement have been developed, but the number of methods useful for human pharmacological studies is limited. The ‘holy grail’ for the measurement of cardiac output would be a method that is accurate, precise, operator independent, fast responding, non-invasive, continuous, easy to use, cheap and safe. This method does not exist today. In this review on cardiac output methods used in pharmacology, the Fick principle, indicator dilution techniques, arterial pul...
Methods of parameters calculation for wastes hightemperature plasma processing
Kolesnyk, Vasyl; Orlyk, Volodymyr
2015-01-01
The article presents the methodology of plasma parameters calculation for different ratios of its constituents and taking into account that plasma jet is both a source of thermal energy and a part of initial reaction mixture for various physical and chemical transformations, in particular, those associated with processing of different solid wastes. As the methodology application example carbon conversion by steam-and-air plasma jet is investigated. У роботі запропоновано методику розрах...
Cost Accounting Methods and Calculation Agricultural Products` Cost
Directory of Open Access Journals (Sweden)
Saule B. Spatayeva
2015-04-01
Full Text Available In the condition of the current market the effective manage of expenses and calculation accountancy of cost production in agriculture must be aimed to control for resources usage at any level of technology process and getting the accountancy database needed for gaining the management targets.The improving the technologies and set up aspects of business entity activity, taken place for the last decades, which caused a significant influence on condition and structure expenses but could not provide the increase of economic effectiveness in agriculture.
Study of calculated and measured time dependent delayed neutron yields
International Nuclear Information System (INIS)
Time-dependent delayed neutron emission is of interest in reactor design, reactor dynamics, and nuclear physics studies. The delayed neutrons from neutron-induced fission of 232U, 237Np, 238Pu, 241Am, /sup 242m/Am, 245Cm, and 249Cf were studied for the first time. The delayed neutron emission from 232Th, 233U, 235U, 238U, 239Pu, 241Pu, and 242Pu were measured as well. The data were used to develop an empirical expression for the total delayed neutron yield. The expression gives accurate results for a large variety of nuclides from 232Th to 252Cf. The data measuring the decay of delayed neutrons with time were used to derive another empirical expression predicting the delayed neutron emission with time. It was found that nuclides with similar mass-to-charge ratios have similar decay patterns. Thus the relative decay pattern of one nuclide can be established by any measured nuclide with a similar mass-to-charge ratio. A simple fission product yield model was developed and applied to delayed neutron precursors. It accurately predicts observed yield and decay characteristics. In conclusion, it is possible to not only estimate the total delayed neutron yield for a given nuclide but the time-dependent nature of the delayed neutrons as well. Reactors utilizing recycled fuel or burning actinides are likely to have inventories of fissioning nuclides that have not been studied until now. The delayed neutrons from these nuclides can now be incorporated so that their influence on the stability and control of reactors can be delineated. 8 figures, 39 tables
Iterative Method for Intrinsic Viscosity Measurements on Perpendicular Recording Media
Kim, Phan Le; Lodder, Cock
2002-01-01
We introduce a new method that allows one to directly measure the intrinsic viscosity (S/sub i/) for perpendicular media using a vibrating sample magnetometer. The measurement is carried out in a number of iterations. In each iteration, the behavior of applied field (H/sub a/) with time is gradually adjusted according to the change in the internal field (H/sub i/) calculated from the relaxation behavior measured in the previous iteration. Eventually, during the last iteration, from which the ...
Projection methods for the calculation of incompressible or dilatable flows
International Nuclear Information System (INIS)
This thesis treats of time resolution methods for the Navier-Stokes equations. Based on the well-known projection method of Chorin and Temam, an original pressure correction method, named 'projection-penalty' is developed. Its specificity concerns the addition of a penalty term in the prediction step, which constrains the predicted velocity to fit with the mass balance. The precision improvements added by this method are demonstrated by some analysis results and by some numerical experiments of incompressible or dilatable flows. Finally, the potentialities offered by the use of the joint finite elements method in this type of fractionary step scheme is studied. Two applications are presented, one for local refinement purpose, the other for the resolution of a multi-physics problem. (J.S.)
A method for the calculation of annual limits on intake
International Nuclear Information System (INIS)
The German Radiation Protection Ordinance issued in 1989 - as well as ICRP Publication 30 - included tables of annual limits on intake (ALIs). These are secondary limits derived to indicate those intake values which are not allowed to be exceeded within a year to meet the primary annual dose limits. The latest ICRP Publications dealing with doses for workers give no ALIs any more and also the IAEA Basic Safety Standards and the Council Directive of the European Commission do not list such values. And also the new Radiation Protection Ordinance as well as the federal gazette with dose coefficients do not include such values any more. However, it may be that they will be included as guiding levels in the calculation principles for the assessment of internal doses. This paper will give reasons why there are no ALIs given any more, it will show how ALIs could be calculated, it will show the influence of additional dose restrictions for female workers of child-bearing age, and it will discuss if radiation protection for the unborn child would be fulfilled if the dose limits of the radiation protection ordinance are met. (orig.)
Filtered thermal neutron captured cross-sections measurements and decay heat calculations
International Nuclear Information System (INIS)
Recently, a pure thermal neutron beam has been developed for neutron capture measurements based on the horizontal channel No.2 of the research reactor at the Nuclear Research Institute, Dalat. The original reactor neutron spectrum is transmitted through an optimal composition of Bi and Si single crystals for delivering a thermal neutron beam with Cadmium ratio (Rcd) of 420 and neutron flux (Φth) of 1.6x106 n/cm2.s. This thermal neutron beam has been applied for measurements of capture cross-sections for nuclide of 51V, 55Mn, 180Hf and 186W by the activation method relative to the standard reaction 197Au(n,g)198Au. In addition to the activities of neutron capture cross-sections measurements, the study on nuclear decay heat calculations has been also considered to be developed at the Institute. Some results on calculation procedure and decay heat values calculated with update nuclear database for 235U, 238U, 239Pu and 232Th are introduced in this report. (author)
Convergent close-coupling method for calculation of electron scattering on hydrogen-like targets
International Nuclear Information System (INIS)
The Convergent Close-Coupling (CCC) method for the calculation of electron-hydrogen scattering was extended to hydrogen-like targets, atoms or ions. These include H, Li, Na, and K atoms, as well as the multitude of ions which have the same isoelectronic sequence as these atoms. The reliability of the method is independent of the projectile energy, and its applicability was demonstrated. It shows excellent agreement with a large set of measurements for electron scattering on sodium at projectile energies ranging from 1 to 54.4 eV. These measurements include spin asymmetries, singlet and triplet angular momentum (L) transferred to the atom perpendicular to the scattering plane, reduced Stokes parameters, differential, integrated, and total cross sections, as well as the total ionization spin asymmetry. The method is found to give better agreement with experiment than any other over this entire energy range. 61 refs., 2 tabs., 10 figs
Dosimetric validation of Acuros XB with Monte Carlo methods for photon dose calculations
International Nuclear Information System (INIS)
Purpose: The dosimetric accuracy of the recently released Acuros XB advanced dose calculation algorithm (Varian Medical Systems, Palo Alto, CA) is investigated for single radiation fields incident on homogeneous and heterogeneous geometries, and a comparison is made to the analytical anisotropic algorithm (AAA). Methods: Ion chamber measurements for the 6 and 18 MV beams within a range of field sizes (from 4.0x4.0 to 30.0x30.0 cm2) are used to validate Acuros XB dose calculations within a unit density phantom. The dosimetric accuracy of Acuros XB in the presence of lung, low-density lung, air, and bone is determined using BEAMnrc/DOSXYZnrc calculations as a benchmark. Calculations using the AAA are included for reference to a current superposition/convolution standard. Results: Basic open field tests in a homogeneous phantom reveal an Acuros XB agreement with measurement to within ±1.9% in the inner field region for all field sizes and energies. Calculations on a heterogeneous interface phantom were found to agree with Monte Carlo calculations to within ±2.0%(σMC=0.8%) in lung (ρ=0.24 g cm-3) and within ±2.9%(σMC=0.8%) in low-density lung (ρ=0.1 g cm-3). In comparison, differences of up to 10.2% and 17.5% in lung and low-density lung were observed in the equivalent AAA calculations. Acuros XB dose calculations performed on a phantom containing an air cavity (ρ=0.001 g cm-3) were found to be within the range of ±1.5% to ±4.5% of the BEAMnrc/DOSXYZnrc calculated benchmark (σMC=0.8%) in the tissue above and below the air cavity. A comparison of Acuros XB dose calculations performed on a lung CT dataset with a BEAMnrc/DOSXYZnrc benchmark shows agreement within ±2%/2mm and indicates that the remaining differences are primarily a result of differences in physical material assignments within a CT dataset. Conclusions: By considering the fundamental particle interactions in matter based on theoretical interaction cross sections, the Acuros XB algorithm is
Godunov Method for Calculating Multicomponent Heterogeneous Medium Flows
Surov, V. S.
2014-03-01
The modified Godunov method intended for integrating the nondivergent systems that describe a multivelocity heterogeneous mixture flow is presented. The linearized Riemann solver has been used in solving the Riemann problems.
A nonlinear analytic function expansion nodal method for transient calculations
Energy Technology Data Exchange (ETDEWEB)
Joo, Han Gyn; Park, Sang Yoon; Cho, Byung Oh; Zee, Sung Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
1998-12-31
The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation of the solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized, In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of application to the NEACRP PWR rod ejection benchmark problems. 6 refs., 2 figs., 1 tab. (Author)
A Green's function nodal expansion method for LWR diffusion calculation
International Nuclear Information System (INIS)
A Green's Function Nodal Expansion Method (GNEM) has been developed for the efficient numerical solution of the LWR multi-dimensional neutron diffusion equation. It is an improved version of Nodal Expansion Method (NEM) and Nodal Green's Function Method (NGFM). The code interior fluxes are approximated by a high order polynomial expansion as in NEM. The nodal surface fluxes are coupled with the net currents by using the Green's function method to improve the accuracy. A computer code GNEM has been developed and tested. The numerical results demonstrate that GNEM has the same accuracy as NGFM, while it is twice as fast as NGFM. Especially, the numerical results of TMI-1 core depletion cycles 1 and 6 demonstrate that GNEM is about two times faster than ADMARC and possesses better accuracy
Emittance measurements by variable quadrupole method
International Nuclear Information System (INIS)
The beam emittance is a measure of both the beam size and beam divergence, we cannot directly measure its value. If the beam size is measured at different locations or under different focusing conditions such that different parts of the phase space ellipse will be probed by the beam size monitor, the beam emittance can be determined. An emittance measurement can be performed by different methods. Here we will consider the varying quadrupole setting method.
Hourly Calculation Method of Air Source Heat Pump Behavior
Ludovico Danza; Lorenzo Belussi; Italo Meroni; Michele Mililli; Francesco Salamone
2016-01-01
The paper describes an hourly simplified model for the evaluation of the energy performance of heat pumps in cooling mode maintaining a high accuracy and low computational cost. This approach differs from the methods used for the assessment of the overall energy consumption of the building, normally placed in the so-called white or black box models, where the transient conduction equation is deterministically and stochastically solved, respectively. The present method wants to be the expressi...
International Nuclear Information System (INIS)
Uranyl minerals form by oxidation and alteration of uraninite, UO2+x, and the UO2 in used nuclear fuels. The thermodynamic database for these phases is extremely limited. However, the Gibbs free energies and enthalpies for uranyl phases may be estimated based on a method that sums polyhedral contributions. The molar contributions of the structural components to Δf Gm0 and Δf Hm0 are derived by multiple regression using the thermodynamic data of phases for which the crystal structures are known. In comparison with experimentally determined values, the average residuals associated with the predicted Δf Gm0 and Δf Hm0 for the uranyl phases used in the model are 0.08 and 0.10%, respectively. There is also good agreement between the predicted mineral stability relations and field occurrences, thus providing confidence in this method for the estimation of Δf Gm0 and Δf Hm0 of the U(VI) phases. This approach provides a means of generating estimated thermodynamic data for performance assessment calcination and a basic for making bounding calcination of phase stabilities and solubilities. (author)
A New Pseudospectral Method for Calculations of Hydrogen Atom in Arbitrary External Fields
Institute of Scientific and Technical Information of China (English)
QIAO Hao-Xue; LI Bai-Wen1
2002-01-01
A new pseudospectral method was introduced to calculate wavefunctions and energy levels of hydrogen atom in arbitrary potential. Some results of hydrogen atom in uniform magnetic fields were presented, high accuracy of results was obtained with simple calculations, and our calculations show very fast convergence. It suggests a new methodfor calculations of hydrogen atom in external fields.
WAKE GEOMETRY CALCULATIONS FOR TILT-ROTOR USING VISCOUS VORTEX METHOD
Institute of Scientific and Technical Information of China (English)
魏鹏; 史勇杰; 徐国华
2013-01-01
A tilt-rotor unsteady flow analytical method has been developed based upon viscous vortex-particle meth-od .In this method ,the vorticity field is divided into small assembled vortex particles .Vortex motion and diffusion are obtained by solving the velocity-vorticity-formed incompressible Navier-Stokes equations using a grid-free La-grangian simulation method .Generation of the newly vortex particles is calculated by using the Weissinger-L lifting surface model .Furthermore ,in order to significantly improve computational efficiency ,a fast multiple method (FMM) is introduced into the calculation of induced velocity and its gradient .Finally ,the joint vertical experimen-tal (JVX) tilt-rotor is taken as numerical examples to analyze .The wake geometry and downwash are investigated for both hover and airplane modes .The proposed method for tilt-rotor flow analysis is verified by comparing its re-sults with those available measured data .Comparison indicates that the current method can accurately capture the complicated tilt-rotor wake variation and be suitable for aerodynamic interaction simulation in complex environ-ments .Additionally ,the aerodynamic interactional characteristics of dual-rotor wake are discussed in different ro-tor distance .Results show that there are significant differences on interactional characteristics between hover mode and airplane mode .
International Nuclear Information System (INIS)
The paper aims to present the main physical principles for selection of design characteristics of the fast reactor control rods (CR) system. The brief analysis of problems of CR physical calculations is given. Four components are described for the correction to the control rod worth calculated by the routine method based on the few - group three - dimensional diffusion code (TRIGEX) in hexagonal geometry. Principle considerations are given for the choice of the original task discretization methods implemented in this code to minimize the total error. Brief information is given about methods and codes used for the evaluation of error components of control rod worths calculated in a standard way. The results of experimental and calculational investigations of control rod physical characteristics are presented. These results were obtained at BFS critical assemblies simulating LMFBR cores. The investigations have been carried out for different types of core configurations. The experimental and calculated values are given on the distortion of power distribution due to the control rod insertion in the core. (author). 51 refs, 9 figs, 5 tabs
Energy Technology Data Exchange (ETDEWEB)
Zagar, T.; Ravnik, M.; Persic, A. (J.Stefan Institute, Ljubljana (Slovenia))
1999-12-15
Results of fuel element burn-up determination by measurement and calculation are given. Fuel element burn-up was calculated with two different programs TRIGLAV and TRIGAC using different models. New TRIGLAV code is based on cylindrical, two-dimensional geometry with four group diffusion approximation. TRIGAC program uses one-dimensional cylindrical geometry with twogroup diffusion approximation. Fuel element burn-up was measured with reactivity method. In this paper comparison and analysis of these three methods is presented. Results calculated with TRIGLAV show considerably better alignment with measured values than results calculated with TRIGAC. Some two-dimensional effects in fuel element burn-up can be observed, for instance smaller standard fuel element burn-up in mixed core rings and control rod influence on nearby fuel elements. (orig.)
Interactions between molecules in screening constants calculations by CHF-GIAO method
International Nuclear Information System (INIS)
Solid ammonia and methyl cyanide has been used as model substances for study of intermolecular effects in screening constants calculation. The NMR gas-to-liquid shift effects have been measured and correlated with theoretical calculations
International Nuclear Information System (INIS)
Many methods are used to calculate the positron lifetime, these methods could be divided into two main types. The first method is atomic superposition approximation method and the second one is the so called energy band calculation method. They are also known as the non-self-consistent field method and self-consistent field method respectively. In this paper, we first introduce the two basic methods and then, we take Si as an example and give our calculation results, these results coincide with our latest experimental results, finally, we discuss the advantages and disadvantages of the two methods
Score Calculation in Informatics Contests Using Multiple Criteria Decision Methods
Skupiene, Jurate
2011-01-01
The Lithuanian Informatics Olympiad is a problem solving contest for high school students. The work of each contestant is evaluated in terms of several criteria, where each criterion is measured according to its own scale (but the same scale for each contestant). Several jury members are involved in the evaluation. This paper analyses the problem…
Transport survey calculations using the spectral collocation method
International Nuclear Information System (INIS)
A novel transport survey code has been developed and is being used to study the sensitivity of stellarator reactor performance to various transport assumptions. Instead of following one of the usual approaches, the steady-state transport equation are solved in integral form using the spectral collocation method. This approach effectively combine the computational efficiency of global models with the general nature of 1-D solutions. A compact torsatron reactor test case was used to study the convergence properties and flexibility of the new method. The heat transport model combined Shaing's model for ripple-induced neoclassical transport, the Chang-Hinton model for axisymmetric neoclassical transport, and neoalcator scaling for anomalous electron heat flux. Alpha particle heating, radiation losses, classical electron-ion heat flow, and external heating were included. For the test problem, the method exhibited some remarkable convergence properties. As the number of basis functions was increased, the maximum, pointwise error in the integrated power balance decayed exponentially until the numerical noise level as reached. Better than 10% accuracy in the globally-averaged quantities was achieved with only 5 basis functions; better than 1% accuracy was achieved with 10 basis functions. The numerical method was also found to be very general. Extreme temperature gradients at the plasma edge which sometimes arise from the neoclassical models and are difficult to resolve with finite-difference methods were easily resolved. 8 refs., 6 figs
Method of measuring luminescence of a material
Energy Technology Data Exchange (ETDEWEB)
Miller, Steven D.
2015-12-15
A method of measuring luminescence of a material is disclosed. The method includes applying a light source to excite an exposed material. The method also includes amplifying an emission signal of the material. The method further includes measuring a luminescent emission at a fixed time window of about 10 picoseconds to about 10 nanoseconds. The luminescence may be radio photoluminescence (RPL) or optically stimulated luminescence (OSL).
Comparison of methods for numerical calculation of continuum damping
Bowden, George; Hole, Matthew; Gorelenkov, Nikolai; Dennis, Graham
2014-01-01
Continuum resonance damping is an important factor in determining the stability of certain global modes in fusion plasmas. A number of analytic and numerical approaches have been developed to compute this damping, particularly in the case of the toroidicity-induced shear Alfv\\'en eigenmode. This paper compares results obtained using an analytical perturbative approach with those found using resistive and complex contour numerical approaches. It is found that the perturbative method does not provide accurate agreement with reliable numerical methods for the range of parameters examined. This discrepancy exists even in the limit where damping approaches zero. When the perturbative technique is implemented using a standard finite element method, the damping estimate fails to converge with radial grid resolution. The finite elements used cannot accurately represent the eigenmode in the region of the continuum resonance, regardless of the number of radial grid points used.
Analytical method of spectra calculations in the Bargmann representation
International Nuclear Information System (INIS)
We formulate a universal method for solving an arbitrary quantum system which, in the Bargmann representation, is described by a system of linear equations with one independent variable, such as one- and multi-photon Rabi models, or N level systems interacting with a single mode of the electromagnetic field and their various generalizations. We explain three types of conditions that determine the spectrum and show their usage for two deformations of the Rabi model. We prove that the spectra of both models are just zeros of transcendental functions, which in one case are given explicitly in terms of confluent Heun functions. - Highlights: • Analytical method of spectrum determination in Bargmann representation is proposed. • Three types of conditions determining spectrum are identified. • Method to two generalizations of the Rabi system is applied
Three-dimensional calculations using the quiet implicit PIC method
International Nuclear Information System (INIS)
Solution of the time-implicit moment equations for electron and ion species, combined with Maxwell's equations, is the kernel of the moment-implicit particle method and of the quiet implicit PIC method, a generalized δf method for electromagnetic plasma simulation. Previous implementations have used a variety of direct and iterative approaches for obtaining solutions to large sparse linear systems. These methods suffer from both excessive computational cost, sometimes negating the advantage of implicit time differencing; and from lack of convergence in some regimes of interest, rendering the method inapplicable. We describe a new formulation of the coupled problem, leading to a symmetric, positive definite system. We also show that this symmetric problem may be efficiently and reliably solved by a conjugate gradient method. A three-dimensional algorithm has been constructed, using a pseudospectral Fourier treatment of the poloidal and toroidal directions, and a finite difference treatment of the radial direction. The radially-dependent, poloidal and toroidal averaged operator is used as a preconditioner. Convergence is rapid, with a typical iteration count of 10 for 10-5 convergence. New results of the two-fluid form of this code to an internal m = 1 internal kink mode will be presented. The algorithm's ability to reproduce kinetic properties of plasmas is being tested with a one-dimensional code, which has recently been modified to permit periodic boundary conditions. When a nonuniform temperature distribution is imposed as an initial condition, the gradients axe reduced by long mean-free-path particles that stream parallel to the magnetic field. Tests of collisionless wave damping have also been conducted for the ion-cyclotron range of frequencies, and results axe compared with analytic predictions
Nuclear data production, calculation and measurement: a global overview of the gamma heating issue
Colombier, A.-C.; Amharrak, H.; Fourmentel, D.; Ravaux, S.; Régnier, D.; Gueton, O.; Hudelot, J.-P.; Lemaire, M.
2013-03-01
The gamma heating evaluation in different materials found in current and future generations of nuclear reactor (EPRTM, GENIV, MTR-JHR), is becoming an important issue especially for the design of many devices (control rod, heavy reflector, in-core & out-core experiments…). This paper deals with the works started since 2009 in the Reactor Studies Department of CEA Cadarache in ordre to answer to several problematic which have been identified as well for nuclear data production and calculation as for experimental measurement methods. The selected subjects are: Development of a Monte Carlo code (FIFRELIN) to simulate the prompt fission gamma emission which represents the major part of the gamma heating production inside the core Production and qualification of new evaluations of nuclear data especially for radiative capture and inelastic neutron scattering which are the main sources of gamma heating out-core Development and qualification of a recommended method for the total gamma heating calculation using the Monte Carlo simulation code TRIPOLI-4 Development, test and qualification of new devices dedicated to the in-core gamma heating measurement as well in MTR-JHR as in zero power facilities (EOLE-MINERVE) of CEA, Cadarache to increase the experimental measurement accuracy.
Nuclear data production, calculation and measurement: a global overview of the gamma heating issue
International Nuclear Information System (INIS)
The gamma heating evaluation in different materials found in current and future generations of nuclear reactor (EPR, GEN-IV, MTR-JHR), is becoming an important issue especially for the design of many devices (control rod, heavy reflector, in-core and out-core experiments...). This paper deals with the works started in 2009 in the Reactor Studies Department of CEA Cadarache in order to answer to several issues which have been identified for nuclear data production and calculation and for experimental measurement methods. The selected subjects are: -) The development of a Monte Carlo code (FIFRELIN) to simulate the prompt fission gamma emission which represents the major part of the gamma heating production inside the core; -) The production and qualification of new evaluations of nuclear data especially for radiative capture and inelastic neutron scattering which are the main sources of gamma heating out-core; -) The development and qualification of a recommended method for the total gamma heating calculation using the Monte Carlo simulation code TRIPOLI-4; and -) The development, test and qualification of new devices dedicated to the in-core gamma heating measurement as well in MTR-JHR as in zero power facilities (EOLE-MINERVE) of CEA, Cadarache in order to increase the experimental measurement accuracy. (authors)
Nuclear data production, calculation and measurement: a global overview of the gamma heating issue
Directory of Open Access Journals (Sweden)
Gueton O.
2013-03-01
Full Text Available The gamma heating evaluation in different materials found in current and future generations of nuclear reactor (EPRTM, GENIV, MTR-JHR, is becoming an important issue especially for the design of many devices (control rod, heavy reflector, in-core & out-core experiments…. This paper deals with the works started since 2009 in the Reactor Studies Department of CEA Cadarache in ordre to answer to several problematic which have been identified as well for nuclear data production and calculation as for experimental measurement methods. The selected subjects are: Development of a Monte Carlo code (FIFRELIN to simulate the prompt fission gamma emission which represents the major part of the gamma heating production inside the core Production and qualification of new evaluations of nuclear data especially for radiative capture and inelastic neutron scattering which are the main sources of gamma heating out-core Development and qualification of a recommended method for the total gamma heating calculation using the Monte Carlo simulation code TRIPOLI-4 Development, test and qualification of new devices dedicated to the in-core gamma heating measurement as well in MTR-JHR as in zero power facilities (EOLE-MINERVE of CEA, Cadarache to increase the experimental measurement accuracy.
Calculating and measuring thermal neutrons exiting from neutron diffractometers collimators
Tafazolee, K
2000-01-01
process, effectiveness of them are studied for the enhancement of the available system. Final conclusion from the simulation process, indicates that the heavy water with the thickness of 50 to 60 cm. is the best moderator for gaining the better thermal neutrons flux for enhancement of P.N.D. in the T.R.R. Powder Neutron Diffractometer y (P.N.D.) is relatively good and practical way for identification of the 3 dimensional construction of materials. In order to exploit the capabilities of this method, in one of the neutron beam of the Tehran Research Reactor (T.R.R.), a collimator embedded inside the concrete wall, direct the neutrons produced in the core reactor towards a monochromator e. Neutrons having been monochromated by 2 nd collimator are then directed towards the sample. Then the pattern of diffracted neutrons from the sample are studied. In order to make the best out of it, neutrons coming to sit on the sample must be of the thermal type. That means the number/amount of thermal neutrons flux in compar...
Measurement and calculation of radon releases from uranium mill tailings
International Nuclear Information System (INIS)
The mining and milling of uranium ores produces large quantities of radioactive wastes. Although relatively small in magnitude compared to tailings from metal mining and extraction processes, the present worldwide production of such tailings exceeds 20 million tonnes annually. There is thus a need to ensure that the environmental and health risks from these materials are reduced to an acceptable level. This report has been written as a complement to another publication entitled Current Practices for the Management and Confinement of Uranium Mill Tailings, IAEA Technical Reports Series No. 335, which provides a general overview of all the important factors in the siting, design and construction of tailings impoundments, and in the overall management of tailings with due consideration give to questions of the release of pollutants from tailings piles. The present report provides a comprehensive overview of the release, control and monitoring of radon, including computational methods. The report was first drafted in 1989 and was then reviewed at an Advisory Group meeting in 1990. 42 refs, 9 figs, 3 tabs
High Resolution Measurements and Electronic Structure Calculations of a Diazanaphthalene
Gruet, Sébastien; Goubet, Manuel; Pirali, Olivier
2014-06-01
Polycyclic Aromatic Hydrocarbons (PAHs) have long been suspected to be the carriers of so called Unidentified Infrared Bands (UIBs). Most of the results published in the literature report rotationally unresolved spectra of pure carbon as well as heteroatom-containing PAHs species. To date for this class of molecules, the principal source of rotational informations is ruled by microwave (MW) spectroscopy while high resolution measurements reporting rotational structure of the infrared (IR) vibrational bands are very scarce. Recently, some high resolution techniques provided interesting new results to rotationally resolve the IR and far-IR bands of these large carbonated molecules of astrophysical interest. One of them is to use the bright synchrotron radiation as IR continuum source of a high resolution Fourier transform (FTIR) spectrometer. We report the very complementary analysis of the [1,6] naphthyridine (a N-bearing PAH) for which we recorded the microwave spectrum at the PhLAM laboratory (Lille) and the high resolution far-infrared spectrum on the AILES beamline at synchrotron facility SOLEIL. MW spectroscopy provided highly accurate rotational constants in the ground state to perform Ground State Combinations Differences (GSCD) allowing the analysis of the two most intense FT-FIR bands in the 50-900 wn range. Moreover, during this presentation the negative value of the inertial defect in the GS of the molecule will be discussed. A. Leger, J. L. Puget, Astron. Astrophys. 137, L5-L8 (1984) L. J. Allamandola et al. Astrophys. J. 290, L25-L28 (1985). Z. Kisiel et al. J. Mol. Spectrosc. 217, 115 (2003) S. Thorwirth et al. Astrophys. J. 662, 1309 (2007) D. McNaughton et al. J. Chem. Phys. 124, 154305 (2011). S. Albert et al. Faraday Discuss. 150, 71-99 (2011) B. E. Brumfield et al. Phys. Chem. Lett. 3, 1985-1988 (2012) O. Pirali et al. Phys. Chem. Chem. Phys. 15, 10141 (2013).
Measurement and Calculation of Frictional Loss in Large Two-Stroke Engines
Vølund, Anders; Klit, Peder
2003-01-01
The total frictional loss in a large two-stroke marine diesel engine is rather well determined. However, the contribution (size and distribution) from the different machine elements are not well known. The aim of this study is to establish methods to measure and calculate friction in the piston assembly and guide shoe system for a large two-stroke marine diesel engine. These components are the two major contributors to the total friction in a two-stroke marine diesel engine. The piston pack r...
CALCULATION OF HELICOPTER ROTOR FLAPPING ANGLES AND COMPARISON WITH MEASURED DATA
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Helicopter rotor flapping angles from hover to low-speed forward flight are calculated and compared with the measured data in this paper. The analytical method is based on a second order lifting-line/full-span free wake model as well as a fully coupled rotor trim model. It is shown that, in order to accurately predict the lateral flapping angle at low advance ratio, it is necessary to use free wake analysis to account for the highly non-uniform inflow induced by the distorted wake geometry at rotor disc plane.
Development of a software package for solid-angle calculations using the Monte Carlo method
International Nuclear Information System (INIS)
Solid-angle calculations play an important role in the absolute calibration of radioactivity measurement systems and in the determination of the activity of radioactive sources, which are often complicated. In the present paper, a software package is developed to provide a convenient tool for solid-angle calculations in nuclear physics. The proposed software calculates solid angles using the Monte Carlo method, in which a new type of variance reduction technique was integrated. The package, developed under the environment of Microsoft Foundation Classes (MFC) in Microsoft Visual C++, has a graphical user interface, in which, the visualization function is integrated in conjunction with OpenGL. One advantage of the proposed software package is that it can calculate the solid angle subtended by a detector with different geometric shapes (e.g., cylinder, square prism, regular triangular prism or regular hexagonal prism) to a point, circular or cylindrical source without any difficulty. The results obtained from the proposed software package were compared with those obtained from previous studies and calculated using Geant4. It shows that the proposed software package can produce accurate solid-angle values with a greater computation speed than Geant4. -- Highlights: • This software package (SAC) can give accurate solid-angle values. • SAC calculate solid angles using the Monte Carlo method and it has higher computation speed than Geant4. • A simple but effective variance reduction technique which was put forward by the authors has been applied in SAC. • A visualization function and a graphical user interface are also integrated in SAC
Ab initio calculations of mechanical properties: Methods and applications
Czech Academy of Sciences Publication Activity Database
Pokluda, J.; Černý, Miroslav; Šob, Mojmír; Umeno, Y.
2015-01-01
Roč. 73, AUG (2015), s. 127-158. ISSN 0079-6425 R&D Projects: GA ČR(CZ) GAP108/12/0311 Institutional support: RVO:68081723 Keywords : Ab initio methods * Elastic moduli * Intrinsic hardness * Stability analysis * Theoretical strength * Intrinsic brittleness/ductility Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 27.417, year: 2014
Hourly Calculation Method of Air Source Heat Pump Behavior
Directory of Open Access Journals (Sweden)
Ludovico Danza
2016-04-01
Full Text Available The paper describes an hourly simplified model for the evaluation of the energy performance of heat pumps in cooling mode maintaining a high accuracy and low computational cost. This approach differs from the methods used for the assessment of the overall energy consumption of the building, normally placed in the so-called white or black box models, where the transient conduction equation is deterministically and stochastically solved, respectively. The present method wants to be the expression of the grey box model, taking place between the previous approaches. The building envelope is defined using a building thermal model realized with a 3 Resistance 1 Capacitance (3R1C thermal network based on the solution of the lumped capacitance method. The simplified model evaluates the energy efficiency ratio (EER of a heat pump through the determination of the hourly second law efficiency of a reversed Carnot cycle. The results of the simplified method were finally compared with those provided by EnergyPlus, a dynamic building energy simulation program, and those collected from an outdoor test cell in real working conditions. The results are presented in temperatures and energy consumptions profiles and are validated using the Bland-Altman test.
Theory and Method of Commercial Bank Credit Risk Measurement
Institute of Scientific and Technical Information of China (English)
BeimingXiao; JinlinLi
2004-01-01
Calculating and measuring credit risk is the key technique of commercial bank management. International relative achievements mainly include Z and ZETA modelof Altman, Standard&pool external rating system, Moody external rating system, KMV model, CreditMetrics model, CreditRisk model, McKinsey model and so on. Chinese relative achievements mainly includes: credit score method, comprehensive estimating method,discriminative analysis method, artificial neural network method etc. This paper analyzes the relative research achievements of credit risk measurement and the future research trend.
Calculation of the renal clearance by dynamic measurement of the excreted activity
International Nuclear Information System (INIS)
Aim: In this paper we present a new method to measure the renal slope-clearance of Tc-99m-MAG-3 in a single-shot model (Excretion-clearance). Method: A renal scintigraphy with Tc-99m-MAG-3 was performed in 22 patients. The excreted activity of the tracer in the kidneys and the bladder was dynamically measured using a double-head gamma-camera. Additionally, the total absorption over the kidneys and the bladder was determined. The Excretion-clearance was calculated in a differential and an integral variant. Simultaneously the 2-compartment-clearance (Sapirstein-clearance), the Oberhausen-clearance and the Bubeck-clearance were calculated. Results: The Sapirstein-clearance is considered as the 'goldstandard' in a single-shot modell. The correlation of the Bubeck-clearance and the Oberhausen-clearance ranged from r=0.96 to r=0.97, the Excretion-clearance (differential-method) correlated with r=0.90. The absolute difference of the clearance-values was lowest comparing the Bubeck-clearance with the Sapirstein-clearance with an average difference of 11%, whereas the Excretion-clearance revealed at least an average difference of 21% and the Oberhausen-clearance of 24%. Discussion: The Excretion-clearance requires a more complicated protocoll measuring the clearance in comparison to the Bubeck-clearance. The results of the excretion-clearance differ more from the Sapirstein-clearance with regard to the examined patient population than the Bubeck-clearance. Regarding the theoretical basis of the methods, we expect advantages of the Excretion-clearance compared with the Bubeck-clearance in patients with compartmental disproportion or with a low clearance. We are going to prove this in combination with the above mentioned methodical improvements in a further study. (orig.)
Cao, Yang-Bing; Feng, Xia-Ting; Yan, E.-Chuan; Chen, Gang; Lü, Fei-fei; Ji, Hui-bin; Song, Kuang-Yin
2016-05-01
Knowledge of the fracture hydraulic aperture and its relation to the mechanical aperture and normal stress is urgently needed in engineering construction and analytical research at the engineering field scale. A new method based on the in situ borehole camera measurement and borehole water-pressure test is proposed for the calculation of the fracture hydraulic aperture. This method comprises six steps. The first step is to obtain the equivalent hydraulic conductivity of the test section from borehole water-pressure tests. The second step is a tentative calculation to obtain the qualitative relation between the reduction coefficient and the mechanical aperture obtained from borehole camera measurements. The third step is to choose the preliminary reduction coefficient for obtaining the initial hydraulic aperture. The remaining three steps are to optimize, using the genetic algorithm, the hydraulic apertures of fractures with high uncertainty. The method is then applied to a fractured granite engineering area whose purpose is the construction of an underground water-sealed storage cavern for liquefied petroleum gas. The probability distribution characteristics of the hydraulic aperture, the relationship between the hydraulic aperture and the mechanical aperture, the hydraulic aperture and the normal stress, and the differences between altered fractures and fresh fractures are all analyzed. Based on the effects of the engineering applications, the method is proved to be feasible and reliable. More importantly, the results of the hydraulic aperture obtained in this paper are different from those results elicited from laboratory tests, and the reasons are discussed in the paper.
A Stochastic Method for Semileptonic Form Factor Calculations on the Lattice
Evans, Richard; Collins, Sara
2009-01-01
We investigate an alternative to the Sequential Propagator Method used in Lattice QCD calculations of semileptonic form factors. We replace the sequential propagator with a stochastic propagator so that, in principle, all momentum and sink smearing combinations are available with only a single spin-color inversion. Practically, the stochastic noise is significant and must be reduced at the cost of more inversions. We study the behavior of the stochastic noise and compare the computational costs of this stochastic technique and the Sequential Propagator Method. We also present preliminary semileptonic form factor results using the stochastic technique on N_f=2 configurations with a non-perturbatively improved Sheikoleslami-Wohlert action generated by the QCDSF collaboration. At a fixed cost, measured in terms of the number of heavy-quark inversions, the method provides more correlators for the extraction of the form factors at various q^2's than the Sequential Propagator Method. These additional correlators re...
International Nuclear Information System (INIS)
A new method for the calculation of sensitivity coefficients is developed. The new method is a combination of two methodologies used for calculating theses coefficients, which are the differential and the generalized perturbation theory methods. The method utilizes as integral parameter the average flux in an arbitrary region of the system. Thus, the sensitivity coefficient contains only the component corresponding to the neutron flux. To obtain the new sensitivity coefficient, the derivatives of the integral parameter, Φ, with respect to σ are calculated using the perturbation method and the functional derivatives of this generic integral parameter with respect to σ and Φ are calculated using the differential method. (author)
A Direct Iteration Method using Resonance Integral Table for the Self-Shielding Calculations
International Nuclear Information System (INIS)
In this paper, a direct iteration method using the resonance integral table is introduced for the self-shielding calculations. The basic purpose of this paper is to show the possibility that the HELIOS subgroup method can be replaced with this method. This method doesn't use the subgroup data but only the resonance integral tables given in library. The basic idea of this method is to use the Bondarenko's iteration in order to obtain the self-shielded effective cross sections with the background cross sections which are calculated by the heterogeneous transport calculation. This method is implemented in the KARMA lattice calculation code and tested
A Direct Iteration Method using Resonance Integral Table for the Self-Shielding Calculations
Energy Technology Data Exchange (ETDEWEB)
Hong, Ser Gi; Kim, Kang Seog; Song, Jae Seung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2009-10-15
In this paper, a direct iteration method using the resonance integral table is introduced for the self-shielding calculations. The basic purpose of this paper is to show the possibility that the HELIOS subgroup method can be replaced with this method. This method doesn't use the subgroup data but only the resonance integral tables given in library. The basic idea of this method is to use the Bondarenko's iteration in order to obtain the self-shielded effective cross sections with the background cross sections which are calculated by the heterogeneous transport calculation. This method is implemented in the KARMA lattice calculation code and tested.
Comparison of methods for numerical calculation of continuum damping
Bowden, George; Könies, Axel; Hole, Matthew; Gorelenkov, Nikolai; Dennis, Graham
2014-01-01
Continuum resonance damping is an important factor in determining the stability of certain global modes in fusion plasmas. A number of analytic and numerical approaches have been developed to compute this damping, particularly in the case of the toroidicity-induced shear Alfv\\'en eigenmode. This paper compares results obtained using an analytical perturbative approach with those found using resistive and complex contour numerical approaches. It is found that the perturbative method does not p...
Relief valve discharge piping calculational methods and results
International Nuclear Information System (INIS)
The analysis of a safety relief valve and its connecting discharge pipe is an important parameter in the design of a light water reactor plant. This paper addresses the computer modelling techniques and methods used for this analysis and presents guidelines, cautions and improvements which should be used for design. Specific discussions include considerations for loop seal design, heat transfer effects, pipe submergence, reflood effects and vacuum breaker design. (orig.)
Free-energy calculation methods for collective phenomena in membranes
Smirnova, Yuliya G.; Fuhrmans, Marc; Barragan Vidal, Israel A.; Müller, Marcus
2015-09-01
Collective phenomena in membranes are those which involve the co-operative reorganization of many molecules. Examples of these are membrane fusion, pore formation, bending, adhesion or fission. The time and length scales, on which these processes occur, pose a challenge for atomistic simulations. Therefore, in order to solve the length scale problem it is popular to introduce a coarse-grained representation. To facilitate sampling of the relevant states additional computational techniques, which encourage the system to explore the free-energy landscape far from equilibrium and visit transition states, are needed. These computational techniques provide insights about the free-energy changes involved in collective transformations of membranes, yielding information about the rate limiting states, the transformation mechanism and the influence of architectural, compositional and interaction parameters. A common approach is to identify an order parameter (or reaction coordinate), which characterizes the pathway of membrane reorganization. However, no general strategy exists to define such an order parameter that can properly describe cooperative reorganizations in membranes. Recently developed methods can overcome this problem of the order-parameter choice and allow us to study collective phenomena in membranes. We will discuss such methods as thermodynamic integration, umbrella sampling, and the string method and results provided by their applications to particle-based simulations, particularly focusing on membrane fusion and pore formation.
Free-energy calculation methods for collective phenomena in membranes
International Nuclear Information System (INIS)
Collective phenomena in membranes are those which involve the co-operative reorganization of many molecules. Examples of these are membrane fusion, pore formation, bending, adhesion or fission. The time and length scales, on which these processes occur, pose a challenge for atomistic simulations. Therefore, in order to solve the length scale problem it is popular to introduce a coarse-grained representation. To facilitate sampling of the relevant states additional computational techniques, which encourage the system to explore the free-energy landscape far from equilibrium and visit transition states, are needed. These computational techniques provide insights about the free-energy changes involved in collective transformations of membranes, yielding information about the rate limiting states, the transformation mechanism and the influence of architectural, compositional and interaction parameters. A common approach is to identify an order parameter (or reaction coordinate), which characterizes the pathway of membrane reorganization. However, no general strategy exists to define such an order parameter that can properly describe cooperative reorganizations in membranes. Recently developed methods can overcome this problem of the order-parameter choice and allow us to study collective phenomena in membranes. We will discuss such methods as thermodynamic integration, umbrella sampling, and the string method and results provided by their applications to particle-based simulations, particularly focusing on membrane fusion and pore formation. (topical review)
Calculation of dose in quartz for comparison with thermoluminescence dosimetry measurements
International Nuclear Information System (INIS)
Gamma radiation from the atomic bombs detonated over Hiroshima and Nagasaki left a record in the quartz grains constituent to the tile and brick in city structures. That record has been read to determine the gamma-ray dose deposited in these grains, using thermoluminescence (TL) dosimetry techniques. Because the quartz grains are imbedded in dense tile and brick material located on structures of complex geometry, the dose in quarts is not an exact measure of the free-field kerma. Therefore, calculations of dose deposition in the quartz grains were performed, using the same free-field fluence data and shielding computation methods as those incorporated in the dosimetry system delivered to the Radiation Effects Research Foundation (RERF) in 1986. This report presents a summary description of the experimental results, including total dose and background dose, as well as the salient features of the tiles and brick, including their locations on the various structures. The report provides a description of the approach used to calculate the dose to the quartz in the tile and brick samples, as well as a detailed tabulation of the calculated dose, including the contribution from each component of A-bomb radiation. Finally, the report provides a comparison of DS86 and T65D dose values with measured results and a discussion of issues raised in the process of that comparison
A method to improve the precision of measuring focusing system
Xu, Xiaoliang; An, Tao; Chen, Ke
2015-10-01
Most of the telescope focusing systems adopt the measuring distance method to focus the quick-moving target because the imaging position of moving target is constantly changing. The focusing system calculates the focal position, controls the motor according to the distance of the target. This focusing method has a faster focusing and a better real-time performance compared to the image focusing method based on the image quality. But restricted by the external environment, the precision of instruments and technical level, Distance measuring focus system(DMFS) generally have low precision, higher dynamic adjusting delay problem. This paper mainly analyses the main error sources affecting the accuracy of DMFS, aiming at the existing defects of commonly used current speed compensation method, put forward a kind of solution path delay lag method predicted method measuring focusing system, and then simulate it, the result shows that this method can greatly improve the precision of DMFS.
Comparison of measured and calculated temperatures for a Mach 8 hypersonic wing test structure
Quinn, R. D.; Fields, R. A.
1986-01-01
Structural temperatures were measured on a hypersonic wing test structure during a heating test that simulated a Mach 8 thermal environment. Measured data are compared to design calculations and temperature predictions obtained from a finite-difference thermal analysis.
Rate Constant Calculation for Thermal Reactions Methods and Applications
DaCosta, Herbert
2011-01-01
Providing an overview of the latest computational approaches to estimate rate constants for thermal reactions, this book addresses the theories behind various first-principle and approximation methods that have emerged in the last twenty years with validation examples. It presents in-depth applications of those theories to a wide range of basic and applied research areas. When doing modeling and simulation of chemical reactions (as in many other cases), one often has to compromise between higher-accuracy/higher-precision approaches (which are usually time-consuming) and approximate/lower-preci
Visual Method for Spectral Energy Distribution Calculation of Blazars
Indian Academy of Sciences (India)
Y. Huang; J. H. Fan
2014-09-01
In this work, we propose to use `The Geometer’s Sketchpad’ to the fitting of a spectral energy distribution of blazar based on three effective spectral indices, RO, OX, and RX and the flux density in the radio band. It can make us to see the fitting in detail with both the peak frequency and peak luminosity given immediately. We used our method to those sources whose peak frequency and peak luminosity are given and found that our results are consistent with those given in the work of Sambruna et al. (1996).
New nuclear medicine method of calculating left ventricular stroke volume
Energy Technology Data Exchange (ETDEWEB)
Gieschke, R.; Luig, H.; Reuter, R.; Figulla, H.R.
1983-12-01
A new non-invasive nuclear medicine procedure for determining the left ventricular stroke volume is described. The procedure exhibits the following features: 1. individual calibration of scintigraphic counts in activity by first-pass evaluation; 2. no need for a delta-shaped bolus injection; and 3. determination of different stroke volumes, e.g. during different grades of exercise, by only one injection and by only one blood sample. 36 results obtained at rest and during exercise are compared with corresponding results of the thermodilution method (r = 0.86).
Directory of Open Access Journals (Sweden)
Szałapak Jerzy
2015-12-01
Full Text Available The Low Temperature Joining Technique (LTJT using silver compounds enables to significantly increase the thermal conductivity between joined elements, which is much higher than for soldered joints. However, it also makes difficult to measure the thermal conductivity of the joint. The Laser Flash Analysis (LFA is a non-intrusive method of measuring the temperature rise of one surface of a specimen after excitation with a laser pulse of its other surface. The main limitation of the LFA method is its standard computer software, which assumes the dimensions of a bonded component to be similar to those of the substrate, because it uses the standard Parker’s formula dedicated for one-dimensional heat flow. In the paper a special design of measured specimen was proposed, consisting of two copper plates of different size joined with the sintered silver layer. It was shown that heat properties of these specimens can also be measured after modifying the LFA method. The authors adapted these specimens by masking the false heat signal sourced from the uncovered plate area. Another adaptation was introducing a correcting factor of the heat travel distance, which was calculated with heat-flow simulations and placed into the Parker’s formula. The heat-flow simulated data were compared with the real LFA measurement results, which enabled estimation of the joint properties, e.g. its porosity.
Handbook of nuclear safeguards measurement methods
International Nuclear Information System (INIS)
This handbook is intended to be a guide to the selection of methods for meeting specific measurement requirements. The information was compiled from a survey of production facilities, the literature, and current exchange programs. The survey included bulk measurements, chemical assay, sampling techniques, isotopic measurements, passive NDA, and active NDA
Contemporary methods of body composition measurement
DEFF Research Database (Denmark)
Fosbøl, Marie Ø; Zerahn, Bo
2015-01-01
Reliable and valid body composition assessment is important in both clinical and research settings. A multitude of methods and techniques for body composition measurement exist, all with inherent problems, whether in measurement methodology or in the assumptions upon which they are based....... This review is focused on currently applied methods for in vivo measurement of body composition, including densitometry, bioimpedance analysis, dual-energy X-ray absorptiometry, computed tomography (CT), magnetic resonance techniques and anthropometry. Multicompartment models including quantification of trace...
Comparison of hardenability calculation methods of the heat-treatable constructional steels
Energy Technology Data Exchange (ETDEWEB)
Dobrzanski, L.A.; Sitek, W. [Division of Tool Materials and Computer Techniques in Metal Science, Silesian Technical University, Gliwice (Poland)
1995-12-31
Evaluation has been made of the consistency of calculation of the hardenability curves of the selected heat-treatable alloyed constructional steels with the experimental data. The study has been conducted basing on the analysis of present state of knowledge on hardenability calculation employing the neural network methods. Several calculation examples and comparison of the consistency of calculation methods employed are included. (author). 35 refs, 2 figs, 3 tabs.
Comparison of the Calculated and Measured Dose under Lead Blocks in Radiation Therapy Photon Beams
International Nuclear Information System (INIS)
Depth dose data for irregularly shaped fields cannot be previously prepared as they usually are for circular and square fields in photon beams of linacs and Cobalt-60 units. Thus we apply a computer program for that purpose, each time inserting the specific field shape into the computer by a digitizer. The program is based on the implementation of the well known Clarkson's method, exactly as described by Khan(1). The method also allows to calculate the dose under blocks in various depths. In order to verify the validity of the program we compared the calculated dose with that one measured in a waterlike phantom made of white polystyrene (PTW's raw water). The calculation also allows to evaluate the contribution of the scatter radiation to the total dose under the blocks. The dose under two lead blocks was measured within a field of 25x25cm2 as measured on the level of isocenter. The size of blocks as compared to the open field is shown in fig.2. The depths of measurements were dmax, 5cm, 10cm and 20 cm (point B in fig2.). The results are expressed in % with respect to the reference point in dmax (point A in fig.2) and are shown in table 1 (Cobalt gamma rays), in table 2 (6MV X rays) and in table 3 (18MV X rays). The fractions shown in brackets represent the contribution of the scattered radiation to the dose under blocks. The results show that the calculation is in excellent agreement with the measurement for small blocks, it somewhat underestimates the dose for large blocks and small depths, but it is satisfactory for the depths greater than 5 cm. The results also show that the contribution of the scattered radiation is essentially higher under small blocks and that it generally increases with the depth. The maximum difference in no case exceeded 2.5 % of the dose in the reference point. From the point of view of radiation protection, this difference can be considered as negligible. On the other hand, from the point of view of radiotherapy the obtained accuracy is
Energy Labelling of Glazings and Windows in Denmark: Calculated and Measured Values
DEFF Research Database (Denmark)
Duer, Karsten; Svendsen, Svend; Mogensen, Morten Møller; Laustsen, Jacob Birck
2002-01-01
results of a comparison between measured and calculated thermal transmittance for five different window types are given. The calculations on the glazing part have been performed in five different programmes (WIS, WINDOW, VISION, CALUMEN and GLAD99). The calculations on the frame part have been performed...... in three different programmes (FRAME, THERM and WinIso). The comparison indicates that all investigated programmes are qualified for calculating energy labelling data for glazings and windows...
Integrate Document Ranking Information into Confidence Measure Calculation for Spoken Term Detection
Liu, Quan; Guo, Wu; Ling, Zhen-Hua
2015-01-01
This paper proposes an algorithm to improve the calculation of confidence measure for spoken term detection (STD). Given an input query term, the algorithm first calculates a measurement named document ranking weight for each document in the speech database to reflect its relevance with the query term by summing all the confidence measures of the hypothesized term occurrences in this document. The confidence measure of each term occurrence is then re-estimated through linear interpolation wit...
Institute of Scientific and Technical Information of China (English)
TANG Yi; FANG Yong-li; YANG Luo; SUN Yu-xin; YU Zheng-hua
2012-01-01
A new accurate calculation method of electric power harmonic parameters was presented.Based on the delay time theorem of Fourier transform,the frequency of the electric power was calculated,and then,suing interpolation in the frequency domain of the windows,the parameters (amplitude and phase) of each harmonic frequency signals were calculated accurately.In the paper,the effect of the delay time and the windows on the electric power harmonic calculation accuracy was analysed.The digital simulation and the physical measurement tests show that the proposed method is effective and has more advantages than other methods which are based on multipoint interpolation especially in calculation time cost; therefore,it is very suitable to be used in the single chip DSP micro-processor.
Finite element method in density functional theory electronic structure calculations
Czech Academy of Sciences Publication Activity Database
Vackář, Jiří; Čertík, Ondřej; Cimrman, R.; Novák, M.; Šipr, Ondřej; Plešek, Jiří
Berlin : Springer, 2012 - (Hoggan, P.; Brändas, E.; Maruani, J.; Piecuch, P.; Delgado- Barrio , G.), s. 199-217 ISBN 978-94-007-2075-6. - (Progress in Theoretical Chemistry and Physics. vol. 12) R&D Projects: GA ČR GA101/09/1630; GA ČR(CZ) GAP108/11/0853; GA MŠk(CZ) LC06040 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z10100521; CEZ:AV0Z20760514 Keywords : finite-element method * pseudopotentials * density functional theory Subject RIV: BM - Solid Matter Physics ; Magnetism http://www.springerlink.com/content/p7k3j7047720270r/
A numerical method for calculating resonant-state wave functions
International Nuclear Information System (INIS)
An initial-value method of numerical solving of Sturm-Liouville problems is applied to find the solution to the Schroedinger equation which corresponds to a resonance situation. The depth of the nuclear potential is regarded as an eigenvalue, which is obtained by iteration. Having established the nuclear potential, the resonant wavefunction is generated by integrating numerically the Schroedinger differential equation inwards from larger radii using the initial conditions of G(r), where G is the irregular Coulomb function. Because the solution is exactly on resonance, nosearching for the phase shift is required. Consequently, the suggested procedure may be employed even if the resonance widths are extremely narrow (e.g., 10-16 MeV)
Study on the Processing Method for Resonance Self-shielding Calculations
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
We investigate a new approach for resonance self-shielding calculations, based on a straightforward subgroup method, used in association with characteristics method. Subgroup method is actually the subdivision of cross section range for resonance energy range.
Calculational methods for estimating skin dose from electrons in Co-60 gamma-ray beams
International Nuclear Information System (INIS)
Several methods have been employed to calculate the relative contribution to skin dose due to scattered electrons in Co-60 γ-ray beams. Either the Klein--Nishina differential scattering probability is employed to determine the number and initial energy of electrons scattered into the direction of a detector, or a Gaussian approximation is used to specify the surface distribution of initial pencil electron beams created by parallel or diverging photon fields. Results of these calculations are compared with experimental data. In addition, that fraction of relative surface dose resulting from photon interactions in air alone is estimated and compared with data extrapolated from measurements at large source--surface distance (SSD). The contribution to surface dose from electrons generated in air is 50% or more of the total skin dose for SSDs greater than 80 cm
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 (1.5stations, up to 50%, because of intensive decomposition of OM and/or organisms respiration in the isolated bottom water. Values of benthic fluxes obtained by the BROM model are within the range of magnitudes measured by chamber experiments and calculated from porewater distributions (Jpw < Jmd < Jch). Using the model it is possible estimate the influence of bioturbation on elements exchange at water-sediment interface. Model has a high resolution in the
A camera based calculation of 99m Tc-MAG-3 clearance using conjugate views method
International Nuclear Information System (INIS)
Background: measurement of absolute or different renal function using radiotracers plays an important role in the clinical management of various renal diseases. Gamma camera quantitative methods is approximations of renal clearance may potentially be as accurate as plasma clearance methods. However some critical factors such as kidney depth and background counts are still troublesome in the use of this technique. In this study the conjugate-view method along with some background correction technique have been used for the measurement of renal activity in99mTc- MAG3 renography. Transmission data were used for attenuation correction and the source volume was considered for accurate background subtraction. Materials and methods: the study was performed in 35 adult patients referred to our department for conventional renography and ERPF calculation. Depending on patients weight approximately 10-15 mCi 99 Tc-MAG3 was injected in the form of a sharp bolus and 60 frames of 1 second followed by 174 frames of 10 seconds were acquired for each patient. Imaging was performed on a dual-head gamma camera(SOLUS; SunSpark10, ADAC Laboratories, Milpitas, CA) anterior and posterior views were acquired simultaneously. A LEHR collimator was used to correct the scatter for the emission and transmission images. Buijs factor was applied on background counts before background correction (Rutland-Patlak equation). gamma camera clearance was calculated using renal uptake in 1-2, 1.5-2.5, 2-3 min. The same procedure was repeated for both renograms obtained from posterior projection and conjugated views. The plasma clearance was also directly calculated by three blood samples obtained at 40, 80, 120 min after injection. Results: 99 Tc-MAG3 clearance using direct sampling method were used as reference values and compared to the results obtained from the renograms. The maximum correlation was found between conjugate view clearance at 2-3 min (R=0.99, R2=0.98, SE=15). Conventional posterior
A high-precision calculation method for interface normal and curvature on an unstructured grid
Ito, Kei; Kunugi, Tomoaki; Ohno, Shuji; Kamide, Hideki; Ohshima, Hiroyuki
2014-09-01
In the volume-of-fluid algorithm, the calculations of the interface normal and curvature are crucially important for accurately simulating interfacial flows. However, few methods have been proposed for the high-precision interface calculation on an unstructured grid. In this paper, the authors develop a height function method that works appropriately on an unstructured grid. In the process, the definition of the height function is discussed, and the high-precision calculation method of the interface normal is developed to meet the necessary condition for a second-order method. This new method has highly reduced computational cost compared with a conventional high-precision method because the interface normal calculation is completed by solving relatively simple algebraic equations. The curvature calculation method is also discussed and the approximated quadric curve of an interface is employed to calculate the curvature. Following a basic verification, the developed height function method is shown to successfully provide superior calculation accuracy and highly reduced computational cost compared with conventional calculation methods in terms of the interface normal and curvature. In addition, the height function method succeeds in calculating accurately the slotted-disk revolution problem and the oscillating drop on unstructured grids. Therefore, the developed height function method is confirmed to be an efficient technique for the high-precision numerical simulation of interfacial flows on an unstructured grid.
Recommended environmental dose calculation methods and Hanford-specific parameters
International Nuclear Information System (INIS)
This document was developed to support the Hanford Environmental Dose overview Panel (HEDOP). The Panel is responsible for reviewing all assessments of potential doses received by humans and other biota resulting from the actual or possible environmental releases of radioactive and other hazardous materials from facilities and/or operations belonging to the US Department of Energy on the Hanford Site in south-central Washington. This document serves as a guide to be used for developing estimates of potential radiation doses, or other measures of risk or health impacts, to people and other biota in the environs on and around the Hanford Site. It provides information to develop technically sound estimates of exposure (i.e., potential or actual) to humans or other biotic receptors that could result from the environmental transport of potentially harmful materials that have been, or could be, released from Hanford operations or facilities. Parameter values and information that are specific to the Hanford environs as well as other supporting material are included in this document
Recommended environmental dose calculation methods and Hanford-specific parameters
Energy Technology Data Exchange (ETDEWEB)
Schreckhise, R.G.; Rhoads, K.; Napier, B.A.; Ramsdell, J.V. (Pacific Northwest Lab., Richland, WA (United States)); Davis, J.S. (Westinghouse Hanford Co., Richland, WA (United States))
1993-03-01
This document was developed to support the Hanford Environmental Dose overview Panel (HEDOP). The Panel is responsible for reviewing all assessments of potential doses received by humans and other biota resulting from the actual or possible environmental releases of radioactive and other hazardous materials from facilities and/or operations belonging to the US Department of Energy on the Hanford Site in south-central Washington. This document serves as a guide to be used for developing estimates of potential radiation doses, or other measures of risk or health impacts, to people and other biota in the environs on and around the Hanford Site. It provides information to develop technically sound estimates of exposure (i.e., potential or actual) to humans or other biotic receptors that could result from the environmental transport of potentially harmful materials that have been, or could be, released from Hanford operations or facilities. Parameter values and information that are specific to the Hanford environs as well as other supporting material are included in this document.
Control rod worth calculations using deterministic and stochastic methods
Energy Technology Data Exchange (ETDEWEB)
Varvayanni, M. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Savva, P., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N. [NCSR ' DEMOKRITOS' , PO Box 60228, 15310 Aghia Paraskevi (Greece)
2009-11-15
Knowledge of the efficiency of a control rod to absorb excess reactivity in a nuclear reactor, i.e. knowledge of its reactivity worth, is very important from many points of view. These include the analysis and the assessment of the shutdown margin of new core configurations (upgrade, conversion, refuelling, etc.) as well as several operational needs, such as calibration of the control rods, e.g. in case that reactivity insertion experiments are planned. The control rod worth can be assessed either experimentally or theoretically, mainly through the utilization of neutronic codes. In the present work two different theoretical approaches, i.e. a deterministic and a stochastic one are used for the estimation of the integral and the differential worth of two control rods utilized in the Greek Research Reactor (GRR-1). For the deterministic approach the neutronics code system SCALE (modules NITAWL/XSDRNPM) and CITATION is used, while the stochastic one is made using the Monte Carlo code TRIPOLI. Both approaches follow the procedure of reactivity insertion steps and their results are tested against measurements conducted in the reactor. The goal of this work is to examine the capability of a deterministic code system to reliably simulate the worth of a control rod, based also on comparisons with the detailed Monte Carlo simulation, while various options are tested with respect to the deterministic results' reliability.
International Nuclear Information System (INIS)
COMURHEX is a plant for converting mining concentrates into UF4. The atmosphere in different facilities is monitored daily using aerosol sampling devices (APA) placed in selected locations depending upon the workstations used by the operators. The results, entered every day into a computer program, can be displayed on individual diagrams for each shop. This program allows urinary uranium analyses over a given threshold to be targeted in addition to the systematic analysis performed periodically. In 1996, 23 urinary analyses corresponding to six events exceeding APA guide values were investigated. A direct approximation of systematic contamination from measurement data has recently been described using a deconvolution of individual monitoring results. Uptakes calculated from urine analysis using this method are correlated with the increase of the APA values. This method implies that a specific monitoring protocol is developed by setting up a minimum number of urinary analyses in one year, a maximum interval between two examinations, considering the chemical composition of the components and the urinary level measurements. Internal dosimetry based only on APA values is not sufficient for operational medical monitoring. To reduce the uncertainties in dose calculation, a special program based on bioassay analysis initiated by the APA guide values is better adapted to estimating the internal dose to each worker in the different facilities of the plant. (author)
Theories and calculation methods for regional objective ET
Institute of Scientific and Technical Information of China (English)
QIN DaYong; LO JinYan; LIU JiaHong; WANG MingNa
2009-01-01
The regional objective ET (Evapotranspiration) is a new concept in water resources research, which refers to the total amount of water that could be exhausted from a region in the form of vapor per year. The objective-ET based water resources management allocates water to different regions in terms of ET. It controls the water exhausted from a region to meet the objective ET. The regional objective ET must be adapted to fit the region's local available water resources. By improving the water utilization effi-ciency and reducing the unrecoverable water in the social water circle, it is saved so that water related production is maintained or even increased under the same water consumption conditions. Regional water balance is realized by rationally deploying the available water among different industries, adjusting industrial structures, and adopting new water-saving technologies, therefore to meeting the requirements for groundwater conservation, agricultural income stability, and avoiding environmental damages. Furthermore, water competition among various departments and industries (including envi-ronmental and ecological water use) may be avoided. This paper proposes an innovative definition of objective ET, and its principles, sub-index systems. Besides, a computational method for regional ob-jective ET is developed by combining the distributed hydrological model and the soil moisture model.
Novel method for sludge blanket measurements.
Schewerda, J; Förster, G; Heinrichmeier, J
2014-01-01
The most widely used methods for sludge blanket measurements are based on acoustic or optic principles. In operation, both methods are expensive and often maintenance-intensive. Therefore a novel, reliable and simple method for sludge blanket measurement is proposed. It is based on the differential pressure measurement in the sludge zone compared with the differential pressure in the clear water zone, so that it is possible to measure the upper and the lower sludge level in a tank. Full-scale tests of this method were done in the secondary clarifier at the waste water treatment plant in Hecklingen, Germany. The result shows a good approximation of the manually measured sludge level. PMID:24569276
Method for Measuring Changes in Surface Tension on Agar
Weisberg, David S.; Dworkin, Martin
1983-01-01
The surface tension of agar surfaces was determined by measuring the contact angles formed by drops of various hydrophobic liquids on the surface and then calculating the composite surface free energy function by solving a series of simultaneous equations derived from these data. This method was used to measure the change in the surface tension of agar produced by the addition of various concentrations of albumin. The resulting curve was typical of the effect of increasing concentrations of s...
Lidar Measurements Supporting the Ocular Hazard Distance Calculation Using Atmospheric Attenuation
Gustafsson, K. Ove S.; Persson, Rolf; Gustafsson, Frank; Berglund, Folke; Hedborg, Julia; Malmquist, Jonas
2016-06-01
A series of lidar measurements has been performed at the Vidsel Test Range, Vidsel, situated in the inland of the very northern part of Sweden, as a part of an assessment of reducing the laser hazard distance using atmospheric attenuation within the calculations of nominal ocular hazard distance (NOHD). The question was "How low is the atmospheric attenuation as function of height in this area, using a wavelength of 1064 nm?" The work included building a ground based backscatter lidar, performing a series of measurements and analyzing the results. The measurements were performed during June to November, 2014, with the objective to measure at clear air and good weather situations. The lidar measurements at 1064 nm showed a very low atmospheric attenuation as a function of height to altitudes of at least 10 km at several occasions. The lowest limit of backscatter coefficient possible to measure with this instrument is 0.3·10-7 m-1 sr-1. Assuming a lidar ratio varying between 30 - 100 sr, this was leading to an extinction coefficient of about 0.9 - 3·10-6 m-1. The atmospheric attenuation reduces the laser hazard distance with about 50 - 56 % depending on the lidar ratio. A recommendation is to monitor the atmospheric attenuation at the occasions when the method to the reduced laser hazard distance using atmospheric attenuation is used.
The truth is out there: measured, calculated and modelled benthic fluxes.
Pakhomova, Svetlana; Protsenko, Elizaveta
2016-04-01
water. Values of benthic fluxes obtained by the BROM model are within the range of magnitudes measured by chamber experiments and calculated from porewater distributions (Jpw changing largely while in chamber experiments they are averaged. As a result, each of the methods has its disadvantages and the main facing us question is - which value should be taken for calculation the balance? This research is funded by VISTA - a basic research program and collaborative partnership between the Norwegian Academy of Science and Letters and Statoil.
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.
Oscillator strengths for high-excitation Ti II from laboratory measurements and calculations
Lundberg, H.; Hartman, H.; Engström, L.; Nilsson, H.; Persson, A.; Palmeri, P.; Quinet, P.; Fivet, V.; Malcheva, G.; Blagoev, K.
2016-04-01
This work reports new experimental radiative lifetimes of six 3d2(3F)5s levels in singly ionized titanium, with an energy around 63000 cm-1 and four 3d2(3F)4p odd parity levels where we confirm previous investigations. Combining the new 5s lifetimes with branching fractions measured previously by Pickering et al. [Astrophys Journal Suppl Ser 132, 403 (2001)], we report 57 experimental log gf values for transitions from the 5s levels. The lifetime measurements are performed using time-resolved laser-induced fluorescence on ions produced by laser ablation. One- and two-step photon excitation is employed to reach the 4p and 5s levels, respectively. Theoretical calculations of the radiative lifetimes of the measured levels as well as of oscillator strengths for 3336 transitions from these levels are reported. The calculations are carried out by a pseudo-relativistic Hartree-Fock method taking into account core polarization effects. The theoretical results are in a good agreement with the experiments and are needed for accurate abundance determinations in astronomical objects.
Method effects and the meaning of measurement
Directory of Open Access Journals (Sweden)
Andrew eMaul
2013-04-01
Full Text Available Although the idea of a method effect in psychological measurement seems intuitively straightforward—that is, it is said to occur when any characteristic of a measurement procedure contributes variance to scores beyond what is attributable to variance in the attribute of interest—much of the surrounding conceptual vocabulary remains confused. In part, these confusions can be traced to deeper confusion in the human science literature regarding the meaning of measurement. In particular, the thinking of human scientists about method effects has been shaped by (a received wisdom regarding why method effects are problematic to begin with, and, therefore, what corrective measures are appropriate, (b the formal and implied semantics of psychometric techniques that have been developed to model method effects, and (c general philosophical undercurrents that have contributed to the collective understanding of psychological measurement. Notably, tensions between lines of thought that can be broadly characterized as empiricist and realist have contributed to uneven thinking surrounding the concept of a method effect. In this paper, it is argued that it may be possible to formulate an account of what method effects are that is coherent not only across different research traditions in the human sciences, but also with thinking found in other scientific disciplines; however, doing so requires a more explicit commitment to a realist position on measurement than is generally forthcoming from human scientists. By examining these issues, this paper hopes to contribute to semantic clarity regarding not just method effects, but also the meaning of measurement in psychology.
Preconditioned Conjugate Gradient methods for low speed flow calculations
Ajmani, Kumud; Ng, Wing-Fai; Liou, Meng-Sing
1993-01-01
An investigation is conducted into the viability of using a generalized Conjugate Gradient-like method as an iterative solver to obtain steady-state solutions of very low-speed fluid flow problems. Low-speed flow at Mach 0.1 over a backward-facing step is chosen as a representative test problem. The unsteady form of the two dimensional, compressible Navier-Stokes equations are integrated in time using discrete time-steps. The Navier-Stokes equations are cast in an implicit, upwind finite-volume, flux split formulation. The new iterative solver is used to solve a linear system of equations at each step of the time-integration. Preconditioning techniques are used with the new solver to enhance the stability and the convergence rate of the solver and are found to be critical to the overall success of the solver. A study of various preconditioners reveals that a preconditioner based on the lower-upper (L-U)-successive symmetric over-relaxation iterative scheme is more efficient than a preconditioner based on incomplete L-U factorizations of the iteration matrix. The performance of the new preconditioned solver is compared with a conventional line Gauss-Seidel relaxation (LGSR) solver. Overall speed-up factors of 28 (in terms of global time-steps required to converge to a steady-state solution) and 20 (in terms of total CPU time on one processor of a CRAY-YMP) are found in favor of the new preconditioned solver, when compared with the LGSR solver.
Subcriticality measurement method for AGN-201 reactor
International Nuclear Information System (INIS)
In order to verify the feasibility and safety of reactor, reactor physics test is performed. The measurement of control rod worth occupies most of period of reactor physics test. For that reason, the new method has been studied for subcriticality measurement to reduce the test period from the economic point of view. Nevertheless, system that can measure or monitor correct subcriticality of nuclear reactor has not been developed yet. If the accurate subcriticality were measured, more efficient of operation would be available and an necessary conservativeness could be removed. In 1980s, the research about subcriticality measurement methodology was performed about subcritical reactor based accelerator, fast breeder reactor and critical experiment reactor. However, study for the Pressurized Water Reactor has been carried on recently. The crucial problem depends on how to correct the spatial effect about signal, neutron source, detector position and measured weak neutron. As the representative measurement methodology, there are Pulse Neutron Source method(PNM), Neutron Noise Analysis, neutron source multiplication method and so on. This paper shows the theoretical analysis of the modified Neutron Source multiplication method (modified NSM method) which is a subcriticality measurement methodology. In the future, measurement of subcriticality will be perform about AGN-201 reactor
Multi-spectral temperature measurement method for gas turbine blade
Gao, Shan; Feng, Chi; Wang, Lixin; Li, Dong
2016-02-01
One of the basic methods to improve both the thermal efficiency and power output of a gas turbine is to increase the firing temperature. However, gas turbine blades are easily damaged in harsh high-temperature and high-pressure environments. Therefore, ensuring that the blade temperature remains within the design limits is very important. There are unsolved problems in blade temperature measurement, relating to the emissivity of the blade surface, influences of the combustion gases, and reflections of radiant energy from the surroundings. In this study, the emissivity of blade surfaces has been measured, with errors reduced by a fitting method, influences of the combustion gases have been calculated for different operational conditions, and a reflection model has been built. An iterative computing method is proposed for calculating blade temperatures, and the experimental results show that this method has high precision.
Utilization of Software Tools for Uncertainty Calculation in Measurement Science Education
International Nuclear Information System (INIS)
Despite its importance, uncertainty is often neglected by practitioners in the design of system even in safety critical applications. Thus, problems arising from uncertainty may only be identified late in the design process and thus lead to additional costs. Although there exists numerous tools to support uncertainty calculation, reasons for limited usage in early design phases may be low awareness of the existence of the tools and insufficient training in the practical application. We present a teaching philosophy that addresses uncertainty from the very beginning of teaching measurement science, in particular with respect to the utilization of software tools. The developed teaching material is based on the GUM method and makes use of uncertainty toolboxes in the simulation environment. Based on examples in measurement science education we discuss advantages and disadvantages of the proposed teaching philosophy and include feedback from students
Directory of Open Access Journals (Sweden)
Odru P.
2006-11-01
Full Text Available Cet article présente une méthode de calcul des structures composites fibres-résine appliquée aux cas des tubes minces. Outre l'établissement des relations contraintes - déformations généralisées des tubes à partir des caractéristiques des matériaux de base et de leur orientation, on pose les relations permettant de calculer leur comportement et leur dimensionnement sous des charges axisymétriques combinées de traction, pression et flexion. Une méthode simplifiée applicable au cas des composites microfissurés est aussi présentée. On montre ensuite, à travers quelques exemples concrets d'applications, les propriétés intéressantes ou inhabituelles que le matériau permet de conférer aux structures. This article presents a method of calculation of composite structures applied to thin-walled tubes. Starting from the characteristics and orientation of the basic materials, the generalized stress-strain equations of the tubes are determined ; then the relationship allowing the calculation of their design and behavior under combined axisymmetrical loads of tension, pressure and bending are established. A simplified method applicable to microcracked composite materials is also described. Several complete examples of applications illustrate the interesting or unusual properties that this material can impart to structures
Methods of measuring residual stresses in components
International Nuclear Information System (INIS)
Highlights: ► Defining the different methods of measuring residual stresses in manufactured components. ► Comprehensive study on the hole drilling, neutron diffraction and other techniques. ► Evaluating advantage and disadvantage of each method. ► Advising the reader with the appropriate method to use. -- Abstract: Residual stresses occur in many manufactured structures and components. Large number of investigations have been carried out to study this phenomenon and its effect on the mechanical characteristics of these components. Over the years, different methods have been developed to measure residual stress for different types of components in order to obtain reliable assessment. The various specific methods have evolved over several decades and their practical applications have greatly benefited from the development of complementary technologies, notably in material cutting, full-field deformation measurement techniques, numerical methods and computing power. These complementary technologies have stimulated advances not only in measurement accuracy and reliability, but also in range of application; much greater detail in residual stresses measurement is now available. This paper aims to classify the different residual stresses measurement methods and to provide an overview of some of the recent advances in this area to help researchers on selecting their techniques among destructive, semi destructive and non-destructive techniques depends on their application and the availabilities of those techniques. For each method scope, physical limitation, advantages and disadvantages are summarized. In the end this paper indicates some promising directions for future developments.
Lesniak, Joseph; Behrman, Elizabeth; Zandler, Melvin; Kumar, Preethika
2008-03-01
Very few quantum algorithms are currently useable today. When calculating molecular energies, using a quantum algorithm takes advantage of the quantum nature of the algorithm and calculation. A few small molecules have been used to show that this method is possible. This method will be applied to larger molecules and compared to classical computer methods.
DEFF Research Database (Denmark)
Zhang, Wen-juan; Huang, Shou-dao; Chen, Zhe
2013-01-01
An analytic electromagnetic calculation method for doubly fed induction generator (DFIG) in wind turbine system was presented. Based on the operation principles, steady state equivalent circuit and basic equations of DFIG, the modeling for electromagnetic calculation of DFIG was proposed. The...... electromagnetic calculation of DFIG was divided into three steps: the magnetic flux calculation, parameters derivation and performance checks. For each step, the detailed numeric calculation formulas were all derived. Combining the calculation formulas, the whole electromagnetic calculation procedure was...... established, which consisted of three iterative calculation loops, including magnetic saturation coefficient, electromotive force and total output power. All of the electromagnetic and performance data of DIFG can be calculated conveniently by the established calculation procedure, which can be used to...
International Nuclear Information System (INIS)
To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values
Perturbation method for calculation of narrow-band impedance and trapped modes
International Nuclear Information System (INIS)
An iterative method for calculation of the narrow-band impedance is described for a system with a small variation in boundary conditions, so that the variation can be considered as a perturbation. The results are compared with numeric calculations. The method is used to relate the origin of the trapped modes with the degeneracy of the spectrum of an unperturbed system. The method also can be applied to transverse impedance calculations. 6 refs., 6 figs., 1 tab
International Nuclear Information System (INIS)
A matrix non-iterative method to calculate the periodical distribution in reactors with thermal regeneration is presented. In case of exothermic reaction, a source term will be included. A computer code was developed to calculate the final temperature distribution in solids and in the outlet temperatures of the gases. The results obtained from ethane oxidation calculation in air, using the Dietrich kinetic data are presented. This method is more advantageous than iterative methods. (E.G.)
Comparisons of Measured and Calculated Neutron Fluxes in Laminated iron and Heavy Water
International Nuclear Information System (INIS)
Measurements of neutron fluxes have been performed in configurations depicting the regions extending radially and axially outwards from the core of a PHWR reactor in order to test the accuracy of the available methods in shield design on thin alternating laminae of Fe and D2O. A 'dry' experimental set-up was constructed, i.e. the D2O was contained in flat tanks made of Al. The first set of measurements was performed through solid Fe and D2O layers, and only the results of these experiments are described in this report. The set-up allowed measurements also in a mock-up of a reactor top penetrated by D2O or air-filled channels (to be reported later). The results are compared to fluxes calculated by the British 18-group removal-diffusion method and by the NRN method developed at AE. The results show that the values predicted may be expected to be within a factor of 2 from the true values in most cases. The predicted relative flux distributions follow the observed ones with a very good accuracy in spite of the apparent misuse of diffusion theory for the thin regions in question. Finally, it is shown that the predicted change in the fast spectrum while penetrating these set-ups should be confirmable with certain threshold detectors
NEW METHOD TO MEASURE PISTON SKIRT DIMENSIONS
Institute of Scientific and Technical Information of China (English)
Qin Yuexia; Hu Dejin
2004-01-01
The measurement of the middle-convex and varying ellipse profile of a piston skirt is a key technology because of its complex profile and high precision. Generally, a piston is measured on special device after it is machined. High accuracy can be achieved through this off-line measurement, but the result diverges from the actual dimension. Therefore, a no-contact in-site measurement system is proposed. A laser displacement meter is used to measure the profile of the piston skirt. A computer connected to the meter is used to process the measured data. A regression analysis method is used to process the ellipse section data. The method of moving average is used to process the middle-convex curve data. By using the given system, high measurement accuracy can be gained, and the production requirement is met.
Contemporary methods of body composition measurement.
Fosbøl, Marie Ø; Zerahn, Bo
2015-03-01
Reliable and valid body composition assessment is important in both clinical and research settings. A multitude of methods and techniques for body composition measurement exist, all with inherent problems, whether in measurement methodology or in the assumptions upon which they are based. This review is focused on currently applied methods for in vivo measurement of body composition, including densitometry, bioimpedance analysis, dual-energy X-ray absorptiometry, computed tomography (CT), magnetic resonance techniques and anthropometry. Multicompartment models including quantification of trace elements by in vivo neutron activation analysis, which are regarded as gold standard methods, are also summarized. The choice of a specific method or combination of methods for a particular study depends on various considerations including accuracy, precision, subject acceptability, convenience, cost and radiation exposure. The relative advantages and disadvantages of each method are discussed with these considerations in mind. PMID:24735332
American Society for Testing and Materials. Philadelphia
2010-01-01
1.1 This guide describes different mathematical methods that may be used to calculate absorbed dose and criteria for their selection. Absorbed-dose calculations can determine the effectiveness of the radiation process, estimate the absorbed-dose distribution in product, or supplement or complement, or both, the measurement of absorbed dose. 1.2 Radiation processing is an evolving field and annotated examples are provided in Annex A6 to illustrate the applications where mathematical methods have been successfully applied. While not limited by the applications cited in these examples, applications specific to neutron transport, radiation therapy and shielding design are not addressed in this document. 1.3 This guide covers the calculation of radiation transport of electrons and photons with energies up to 25 MeV. 1.4 The mathematical methods described include Monte Carlo, point kernel, discrete ordinate, semi-empirical and empirical methods. 1.5 General purpose software packages are available for the calcul...
Directory of Open Access Journals (Sweden)
Mikulović Jovan Č.
2014-01-01
Full Text Available A methodology for calculation of overvoltages in transformer windings, based on a numerical method of inverse Laplace transform, is presented. Mathematical model of transformer windings is described by partial differential equations corresponding to distributed parameters electrical circuits. The procedure of calculating overvoltages is applied to windings having either isolated neutral point, or grounded neutral point, or neutral point grounded through impedance. A comparative analysis of the calculation results obtained by the proposed numerical method and by analytical method of calculation of overvoltages in transformer windings is presented. The results computed by the proposed method and measured voltage distributions, when a voltage surge is applied to a three-phase 30 kVA power transformer, are compared. [Projekat Ministartsva nauke Republike Srbije, br. TR-33037 i br. TR-33020
Evaluation of Monte Carlo Codes Regarding the Calculated Detector Response Function in NDP Method
Energy Technology Data Exchange (ETDEWEB)
Tuan, Hoang Sy Minh; Sun, Gwang Min; Park, Byung Gun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2014-10-15
The basis of the NDP is the irradiation of a sample with a thermal or cold neutron beam and the subsequent release of charged particles due to neutron-induced exoergic charged particle reactions. Neutrons interact with the nuclei of elements and release mono-energetic charged particles, e.g. alpha particles or protons, and recoil atoms. Depth profile of the analyzed element can be obtained by making a linear transformation of the measured energy spectrum by using the stopping power of the sample material. A few micrometer of the material can be analyzed nondestructively, and on the order of 10nm depth resolution can be obtained depending on the material type with NDP method. In the NDP method, the one first steps of the analytical process is a channel-energy calibration. This calibration is normally made with the experimental measurement of NIST Standard Reference Material sample (SRM-93a). In this study, some Monte Carlo (MC) codes were tried to calculate the Si detector response function when this detector accounted the energy charges particles emitting from an analytical sample. In addition, these MC codes were also tried to calculate the depth distributions of some light elements ({sup 10}B, {sup 3}He, {sup 6}Li, etc.) in SRM-93a and SRM-2137 samples. These calculated profiles were compared with the experimental profiles and SIMS profiles. In this study, some popular MC neutron transport codes are tried and tested to calculate the detector response function in the NDP method. The simulations were modeled based on the real CN-NDP system which is a part of Cold Neutron Activation Station (CONAS) at HANARO (KAERI). The MC simulations are very successful at predicting the alpha peaks in the measured energy spectrum. The net area difference between the measured and predicted alpha peaks are less than 1%. A possible explanation might be bad cross section data set usage in the MC codes for the transport of low energetic lithium atoms inside the silicon substrate.