Polinomno analitičko rješenje za jednobrzinsko razlaženje neutrona u sloju uz provjereno sadržane Mark-Marshakove granične uvjete

Boubaker polynomials are used to obtain analytical solutions to the one-speed neutron transport equation for strongly anisotropic scattering. The main advantage of the method lies in proposing solution terms which verify inherent symmetry and Mark-Marshak boundary conditions prior to resolution process. This original feature results in convergent and accurate solutions. Boubaker polynomials expansion scheme is further applied to homogeneous slab problem with strongly anisotropic scattering and vacuum boundaries. Parallel to the classical formulation, the kernels for scattered and fission neutrons are originally chosen on the basis of most realistic models. The results, expressed in terms of linear extrapolation distance de, are recorded and compared to those presented in the related literature.Primjenjuju se Boubakerovi polinomi za dobivanje analitičkog rješenja jednadžbe za razlaženje neutrona jedne brzine pri jako anizotropnom raspršenju. Osnovna prednost metode sastoji se u traženju rješenja preko članova koji provjeravaju unutarnju simetriju i Mark-Marshakove granične uvjete prije postupka razvoja. Ta izvorna odlika vodi na konvregentna i točna rješenja. Boubakerova se polinomna shema razvoja zatim primjenjuje na problem jednolikog sloja s jako neizotropnim raspršenjem i granicama s vakuumom. Usporedo s klasičnim predstavljanjem, jezgre za raspršene i diobene neutrone se izvorno odabiru na osnovi najstvarnijih modela. Ishodi računa, izraženi preko linearne ekstrapolacijske duljine de, prikazuju se i uspoređuju s objavljenima

Polinomno analitičko rješenje za jednobrzinsko razlaženje neutrona u sloju uz provjereno sadržane Mark-Marshakove granične uvjete

Boubaker polynomials are used to obtain analytical solutions to the one-speed neutron transport equation for strongly anisotropic scattering. The main advantage of the method lies in proposing solution terms which verify inherent symmetry and Mark-Marshak boundary conditions prior to resolution process. This original feature results in convergent and accurate solutions. Boubaker polynomials expansion scheme is further applied to homogeneous slab problem with strongly anisotropic scattering and vacuum boundaries. Parallel to the classical formulation, the kernels for scattered and fission neutrons are originally chosen on the basis of most realistic models. The results, expressed in terms of linear extrapolation distance de, are recorded and compared to those presented in the related literature.Primjenjuju se Boubakerovi polinomi za dobivanje analitičkog rješenja jednadžbe za razlaženje neutrona jedne brzine pri jako anizotropnom raspršenju. Osnovna prednost metode sastoji se u traženju rješenja preko članova koji provjeravaju unutarnju simetriju i Mark-Marshakove granične uvjete prije postupka razvoja. Ta izvorna odlika vodi na konvregentna i točna rješenja. Boubakerova se polinomna shema razvoja zatim primjenjuje na problem jednolikog sloja s jako neizotropnim raspršenjem i granicama s vakuumom. Usporedo s klasičnim predstavljanjem, jezgre za raspršene i diobene neutrone se izvorno odabiru na osnovi najstvarnijih modela. Ishodi računa, izraženi preko linearne ekstrapolacijske duljine de, prikazuju se i uspoređuju s objavljenima

Boubakerova shema razvoja po polinomima (BPES) i optička svojstva prskanih slojeva β-SnS2

β-SnS2 layers have been prepared on glass substrates by spray pyrolysis technique at temperature Ts ≈ 270◦C. The transmission-reflectance spectra, subjected to an original BPES-related protocol, led to accurate calculations of the effective absorptivity. The knowledge of lastly obtained values of the thermal diffusivity allowed the determination of the opto-thermal expansivity ψAB as a guide to evaluating the conjoint optical and thermal performances of the as-grown layers.Na staklenoj podlozi priredili smo slojeve β-SnS2 metodom vrućeg prskanja na temperaturi 270◦C. Spektri prolazne i odrazne svjetlosti, izvedeni primjenom nove sheme razvoja po Boubakerovim polinomima, omogućili su točno određivanje efektivne apsorptivnosti. Konačno dobiveni podaci za termalnu difuzivnost omogućili su određivanje opto-termičkog širenja ψAB kao vodilju za određivanje povezanih optičkih i termičkih svojstava svježe pripremljenih slojeva

Boubakerova shema razvoja po polinomima (BPES) i optička svojstva prskanih slojeva β-SnS2

β-SnS2 layers have been prepared on glass substrates by spray pyrolysis technique at temperature Ts ≈ 270◦C. The transmission-reflectance spectra, subjected to an original BPES-related protocol, led to accurate calculations of the effective absorptivity. The knowledge of lastly obtained values of the thermal diffusivity allowed the determination of the opto-thermal expansivity ψAB as a guide to evaluating the conjoint optical and thermal performances of the as-grown layers.Na staklenoj podlozi priredili smo slojeve β-SnS2 metodom vrućeg prskanja na temperaturi 270◦C. Spektri prolazne i odrazne svjetlosti, izvedeni primjenom nove sheme razvoja po Boubakerovim polinomima, omogućili su točno određivanje efektivne apsorptivnosti. Konačno dobiveni podaci za termalnu difuzivnost omogućili su određivanje opto-termičkog širenja ψAB kao vodilju za određivanje povezanih optičkih i termičkih svojstava svježe pripremljenih slojeva

Renewable Energy in Eastern North Africa in Terms of Patterns of Coupling to Czisch European HVDC Super Grid

In this study, wind energy potential and perspectives in the eastern North Africa region (Tunisia) have been investigated in terms of connectivity to the projected Czisch European HVDC super grid. A simplified extracted scheme of this grid has been used as a guide to optimize transportation efficiency through the whole net. Wind, as an available and easily exploitable renewable energy was showing to have a promising future for 2025 horizon in the context of a connected net with the European Union, despite local sub-grids disparities. This is also to emphasis HVDC technology adequacy for economical power transmission over very long distances andconnection between differently established grids

A Numerical Approach for Solving Optimal Control Problems Using the Boubaker Polynomials Expansion Scheme

In this paper, we present a computational method for solving optimal control problems and the controlled Duffing oscillator. This method is based on state parametrization. In fact, the state variable is approximated by Boubaker polynomials with unknown coefficients. The equation of motion, performance index and boundary conditions are converted into some algebraic equations. Thus, an optimal control problem converts to a optimization problem, which can then be solved easily. By this method, the numerical value of the performance index is obtained. Also, the control and state variables can be approximated as functions of time. Convergence of the algorithms is proved. Numerical results are given for several test examples to demonstrate the applicability and efficiency of the method

Nonparametric Estimation of the Conditional Distribution Function For Surrogate Data by the Regression Model

The main objective of this paper is to estimate the conditional cumulative distribution using the nonparametric kernel method for a surrogated scalar response variable given a functional random one. We introduce the new kernel type estimator for the conditional cumulative distribution function (cond-cdf) of this kind of data. Afterward, we estimate the quantile by inverting this estimated cond-cdf and state the asymptotic properties. The uniform almost complete convergence (with rate) of the kernel estimate of this model and the quantile estimator is established. Finally, a simulation study completed to show how our methodology can be adopted

Influence of annealing and processing conditions on nano-structured thin films of tungsten trioxide

Transition metal oxides represent a novel class of compounds which have attracted a considerable interest in the recent literature. Among these materials, tungsten trioxide has shown great potential due to photo-oxidation of water with visible light, high photocurrent with nano-crystals and good sensing properties towards several gases. The purpose of this study is to investigate the influence of conditions of heat treatment on properties of WO3 thin films prepared by hermal evaporation under vacuum. Physico-chemical properties of WO3 thin layers for different heat processing conditions were determined by X-ray diffraction XRD, microprobe electronics and scanning electron microscopy (SEM).Optical measurement yieldedt ransmission and reflection measurements. The study of the physicochemical properties of thin layers of thermally post-treated tungsten trioxide showed that layers processed under vacuum have an unidentifiable structure than those annealed in air and crystallized under different crystallographic structures depending on processing temperature. Layers annealed in oxygen hadmonoclinic crystalline structures.It has been recorded that crystallinity and transmission of these films were drastically improved

Differential quadrature method (DQM) and Boubaker Polynomials Expansion Scheme (BPES) for efficient computation of the eigenvalues of fourth-order Sturm-Liouville problems

The differential quadrature method (DQM) and the Boubaker Polynomials Expansion Scheme (BPES) are applied in order to compute the eigenvalues of some regular fourth-order Sturm-Liouville problems. Generally, these problems include fourth-order ordinary differential equations together with four boundary conditions which are specified at two boundary points. These problems concern mainly applied-physics models like the steady-state Euler-Bernoulli beam equation and mechanicals non-linear systems identification. The approach of directly substituting the boundary conditions into the discrete governing equations is used in order to implement these boundary conditions within DQM calculations. It is demonstrated through numerical examples that accurate results for the first kth eigenvalues of the problem, where k= 1,. 2,. 3,. .... , can be obtained by using minimally 2(k+. 4) mesh points in the computational domain. The results of this work are then compared with some relevant studies. © 2011 Elsevier Inc