A generalized perturbation method for bi-linear functionals of the real and adjoint neutron fluxes

1967 ◽  
Vol 21 (10) ◽  
pp. 755-765 ◽  
Author(s):  
A. Gandini
Keyword(s):  
Perturbation Method ◽  
Linear Functionals ◽  
The Real

scholarly journals The heuristically-based generalized perturbation theory

2021 ◽  
Vol 7 ◽  
pp. 7
Author(s):  
Augusto Gandini
Keyword(s):  
Perturbation Theory ◽  
Perturbation Method ◽  
Linear Analysis ◽  
Linear Functionals ◽  
Fast Reactors ◽  
The Real ◽  
Generalized Perturbation Theory ◽  
Sensitivity Studies

The generalized perturbation method is described relevant to ratios of bi-linear functionals of the real and adjoint neutron fluxes of critical multiplying systems. Simple linear analysis for optimization and sensitivity studies are then feasible relative to spectrum and space-dependent quantities, such as Doppler and coolant void reactivity effects in fast reactors.

SPATIAL FLUCTUATIONS OF THE ORDER PARAMETER IN A DISORDERED SUPERCONDUCTOR WITH p-WAVE PAIRING

2002 ◽  
Vol 16 (03) ◽  
pp. 453-461 ◽  
Author(s):  
GRZEGORZ LITAK
Keyword(s):  
Perturbation Method ◽  
Hubbard Model ◽  
Order Parameter ◽  
Pairing Symmetry ◽  
P Wave ◽  
Real Solution ◽  
The Real ◽  
Wave Pairing ◽  
Spatial Fluctuations ◽  
Effect Of Disorder

The effect of nonmagnetic disorder on the pairing amplitude is studied by means of a perturbation method. Using an extended one band Hubbard model with an intersite attraction we analyze various solutions of p-wave pairing symmetry and discuss their instability calculating fluctuations of order parameter. The model is applied to describe the effect of disorder in Sr2RuO4. The results shows that the real solution with line nodes can be favoured by disorder.

scholarly journals Research on Mathematical Model for Non-Uniformly Qualitative Suspension Cable

2018 ◽  
Vol 175 ◽  
pp. 03039
Author(s):  
Hu Yong ◽  
Du Yuxin ◽  
Cao Yong ◽  
Wang MaoSen ◽  
Ma Yuchi ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Perturbation Method ◽  
Radio Telescope ◽  
Theoretical Basis ◽  
Transcendental Function ◽  
Concentrated Loads ◽  
Real Situation ◽  
The Real ◽  
Suspension Cable ◽  
The Mathematical Model

Catenary theory is recognized as the most effective suspension theory which can reflect the real situation of suspension. Catenary equation belongs to transcendental function, so there are some difficulties in calculation and application. Parabola theory, suspension curve theory and perturbation method are gradually formed as the theoretical basis for the study of suspension cables. This paper takes the 500m spherical radio telescope project as the background. The modeling method of suspension cable under multiple concentrated loads is analyzed, and the mathematical model of supporting cable after load is derived. The research in this paper provides a reference for the establishment of mathematical model of suspension cable in practice.

Stochastic inversion of facies from seismic data based on sequential simulations and probability perturbation method

Geophysics ◽  
2012 ◽  
Vol 77 (4) ◽  
pp. M53-M72 ◽  
Author(s):  
Dario Grana ◽  
Tapan Mukerji ◽  
Jack Dvorkin ◽  
Gary Mavko
Keyword(s):  
Perturbation Method ◽  
Optimization Problems ◽  
Synthetic Seismograms ◽  
Perturbation Approach ◽  
Reservoir Properties ◽  
Stochastic Inversion ◽  
The Real ◽  
Probabilistic Information ◽  
Reservoir Models ◽  
Probability Perturbation Method

We presented a new methodology for seismic reservoir characterization that combined advanced geostatistical methods with traditional geophysical models to provide fine-scale reservoir models of facies and reservoir properties, such as porosity and net-to-gross. The methodology we proposed was a stochastic inversion where we simultaneously obtained earth models of facies, rock properties, and elastic attributes. It is based on an iterative process where we generated a set of models of reservoir properties by using sequential simulations, calculated the corresponding elastic attributes through rock-physics relations, computed synthetic seismograms and, finally, compared these synthetic results with the real seismic amplitudes. The optimization is a stochastic technique, the probability perturbation method, that perturbs the probability distribution of the initial realization and allows obtaining a facies model consistent with all available data through a relatively small number of iterations. The probability perturbation approach uses the Tau model probabillistic method, which provides an analytical representation to combine single probabilistic information into a joint conditional probability. The advantages of probability perturbation method are that it transforms a 3D multiparameter optimization problem into a set of 1D optimization problems and it allowed us to include several probabilistic information through the Tau model. The method was tested on a synthetic case where we generated a set of pseudologs and the corresponding synthetic seismograms. We then applied the method to a real well profile, and finally extended it to a 2D seismic section. The application to the real reservoir study included data from three wells and partially stacked near and far seismic sections, and provided as a main result the set of optimized models of facies, and of the relevant petrophysical properties, to be the initial static reservoir models for fluid flow reservoir simulations.

Algebras which represent their linear functionals

1953 ◽  
Vol 49 (1) ◽  
pp. 1-14 ◽  
Author(s):  
F. F. Bonsall ◽  
A. W. Goldie
Keyword(s):  
Vector Space ◽  
Linear Functional ◽  
Real Field ◽  
Linear Functionals ◽  
The Real ◽  
Banach Theorem ◽  
Real Linear

This paper was originally intended to contain a generalization of a theorem of Banach on the extension of linear functionals. This generalized theorem now appears as a by-product of a study of a class of algebras which we believe to be of much greater interest than the theorem itself. Let X be a vector space over the real field and let π(x) be a sub-additive, positive-homogeneous functional on X. Banach ((2), pp. 27–9) proves that any real linear functional f on a subspace X0 of X which satisfies f(x) ≤ π(x) on X0 can be extended to a real linear functional F on X with F(x) ≤ π(x) on X. One of the essential differences between this theorem and the Hahn-Banach theorem is that π can take negative values.

Reliability Design for Automobile Rear Axle by Perturbation Method

2014 ◽  
Vol 551 ◽  
pp. 228-231
Author(s):  
Shu Kui Han ◽  
Rui Guo ◽  
Yi Cai
Keyword(s):  
Perturbation Method ◽  
Calculation Result ◽  
Rear Axle ◽  
Reliability Theory ◽  
Reliability Estimate ◽  
Reliability Design ◽  
The Real ◽  
Real Size

In this paper, the application of reliability theory in the automobile rear axle has been studied. Essential theory and formulation for reliability estimate and design for rear axle are provided by perturbation method. The example in this paper has proved that the calculation result of the reliability design by using the perturbation method is very consistent with the real size of e-statistical rethsult. So, perturbation method can be widely applied in the rear axle’s design.

scholarly journals Laguerre–Hahn orthogonal polynomials on the real line

2019 ◽  
Vol 09 (01) ◽  
pp. 2040001
Author(s):  
Maria Das Neves Rebocho
Keyword(s):  
Differential Equation ◽  
Differential Equations ◽  
Orthogonal Polynomials ◽  
Real Line ◽  
Linear Functionals ◽  
Recurrence Coefficients ◽  
Stieltjes Functions ◽  
The Real ◽  
Polynomial Coefficients ◽  
Type Differential Equation

A survey is given on sequences of orthogonal polynomials related to Stieltjes functions satisfying a Riccati type differential equation with polynomial coefficients — the so-called Laguerre–Hahn class. The main goal is to describe analytical aspects, focusing on differential equations for those orthogonal polynomials, difference and differential equations for the recurrence coefficients, and distributional equations for the corresponding linear functionals.

Scanning electron microscopy of human iliac bone by a simple preparation method

1990 ◽  
Vol 48 (3) ◽  
pp. 226-227
Author(s):  
Toshihiko Takita ◽  
Tomonori Naguro ◽  
Toshio Kameie ◽  
Akihiro Iino ◽  
Kichizo Yamamoto
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Real Surface ◽  
Public Attention ◽  
Preparation Methods ◽  
The Real ◽  
Simple Preparation ◽  
Scanning Electron

Recently with the increase in advanced age population, the osteoporosis becomes the object of public attention in the field of orthopedics. The surface topography of the bone by scanning electron microscopy (SEM) is one of the most useful means to study the bone metabolism, that is considered to make clear the mechanism of the osteoporosis. Until today many specimen preparation methods for SEM have been reported. They are roughly classified into two; the anorganic preparation and the simple preparation. The former is suitable for observing mineralization, but has the demerit that the real surface of the bone can not be observed and, moreover, the samples prepared by this method are extremely fragile especially in the case of osteoporosis. On the other hand, the latter has the merit that the real information of the bone surface can be obtained, though it is difficult to recognize the functional situation of the bone.

Personal Audio System: Hearing Symptoms, Habits, and Sound Pressure Levels Measured in Real Ear and a Manikin

2020 ◽  
Vol 63 (6) ◽  
pp. 2016-2026
Author(s):  
Tamara R. Almeida ◽  
Clayton H. Rocha ◽  
Camila M. Rabelo ◽  
Raquel F. Gomes ◽  
Ivone F. Neves-Lobo ◽  
...  
Keyword(s):  
Sound Pressure ◽  
Daily Basis ◽  
Cross Sectional Study ◽  
Normal Hearing ◽  
Chi Square ◽  
Cross Sectional ◽  
The Real ◽  
Significant Difference ◽  
Sound Pressure Levels ◽  
Audio System

Purpose The aims of this study were to characterize hearing symptoms, habits, and sound pressure levels (SPLs) of personal audio system (PAS) used by young adults; estimate the risk of developing hearing loss and assess whether instructions given to users led to behavioral changes; and propose recommendations for PAS users. Method A cross-sectional study was performed in 50 subjects with normal hearing. Procedures included questionnaire and measurement of PAS SPLs (real ear and manikin) through the users' own headphones and devices while they listened to four songs. After 1 year, 30 subjects answered questions about their usage habits. For the statistical analysis, one-way analysis of variance, Tukey's post hoc test, Lin and Spearman coefficients, the chi-square test, and logistic regression were used. Results Most subjects listened to music every day, usually in noisy environments. Sixty percent of the subjects reported hearing symptoms after using a PAS. Substantial variability in the equivalent music listening level (Leq) was noted ( M = 84.7 dBA; min = 65.1 dBA, max = 97.5 dBA). A significant difference was found only in the 4-kHz band when comparing the real-ear and manikin techniques. Based on the Leq, 38% of the individuals exceeded the maximum daily time allowance. Comparison of the subjects according to the maximum allowed daily exposure time revealed a higher number of hearing complaints from people with greater exposure. After 1 year, 43% of the subjects reduced their usage time, and 70% reduced the volume. A volume not exceeding 80% was recommended, and at this volume, the maximum usage time should be 160 min. Conclusions The habit of listening to music at high intensities on a daily basis seems to cause hearing symptoms, even in individuals with normal hearing. The real-ear and manikin techniques produced similar results. Providing instructions on this topic combined with measuring PAS SPLs may be an appropriate strategy for raising the awareness of people who are at risk. Supplemental Material https://doi.org/10.23641/asha.12431435

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