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In this paper, we study the shape preserving interpolation for positive data using a rational quartic spline which has a quartic numerator and linear denominator. The rational quartic splines have GC1 continuity at join knots. Simple data dependent constraints are derived on the shape parameters in the description of the rational interpolant. Numerical comparison between the proposed scheme and the existing scheme is discussed. The results indicate that the proposed scheme works well for all tested data sets. [ABSTRACT FROM AUTHOR]

The vortex rope in a hydro turbine draft cone is one the main and strong sources of pulsations in non-optimal modes of hydro turbine operation. The subject of this paper consists in development of a numerical procedure to study the absolute/convective hydrodynamic instability of the swirl flow downstream the Francis turbine runner by means of parallel computing. As an alternative to classical methods as finite volume and finite element methods, the present paper proposes a new approach of the analysis of the swirling flow based on the method of orthogonal decomposition. This method has the benefit of reducing the computational time compared to other techniques. The important point of this paper is that highlights the validation of the numerical results computed by means of the proposed technique with corresponding published results. Moreover, the algorithm provided the growth rate curve as function of mode number both in absolute and convective analysis, some presumptions on the streamwise development of the instability in the vortex thus being made. [ABSTRACT FROM AUTHOR]

This paper concerns the numerical solution of the Black-Scholes PDE with a Neumann boundary condition on the right boundary. We consider finite difference schemes for the semi-discretization, which leads to a system of ODEs with corresponding matrix M. In this paper stability bounds for exp(tM) (t ≥ 0) are proved. A scaled version of the Euclidean norm, denoted by | · |H is considered. The advection and diffusion term of the PDE are analyzed separately. It turns out that the Neumann boundary condition leads to a growth of |exp(tM)|H with the number of grid points m for the pure advection problem. [ABSTRACT FROM AUTHOR]

A type of capacitance probe performance with two brass electrodes intertwined on the outer wall of insulation pipe like a double helix is investigated numerically in this paper, which can measure water fraction in air-oil-water two or three-phase flow in oil industry. The motivation of this paper is to optimize this kind of probe to improve its electric response and spatial resolution and so a 3-D numerical simulation using finite element method is employed to evaluate the effect of electrodes configuration of this capacitance probe on measuring water fraction in horizontal pipes. The electrostatic field of the probe is preliminarily analyzed referred to stratified flow of air-water two-phase flow regime. Several parameters are considered as main variables which have an important effect on the precision of the probe, such as central angle, position angle and length of the two electrodes. From the electrostatic field analysis, lumped capacitance between the two electrodes is obtained in every different electrode geometry model and the results of each model are compared to each other in order to select a better arrangement of the electrodes that has a better response to water fraction. And by using circuit simulation method, the numerical calculated lumped capacitance is transferred to voltage output through the circuit used in the experiment. The relationship between voltage and water fraction of calculated and experimental result are compared in order to test the reasonableness of the simulation. The results show that at high water fraction, the difference between numerical and measured data agrees very well. [ABSTRACT FROM AUTHOR]

In the present paper, a time-dependent numerical model for the design of a climatic chamber is been developed. The reference is made to the design of a chamber suitable for tracked and wheeled tractors, i.e. having measures 5x8x4 m³ (length x width x height). In order to support the theoretical predictions for the design, a numerical analysis is performed by employing Matlab-Simulink, a software package devoted to the simulation of the behavior of transient systems. Reference is made to simulate the air conditioning system of the tractor in both the two cases: the “winter case” and the “summer case”, as prescribed by the ISO 14269-2:1997 standard. In fact, in order to achieve the compulsory European type approval for tracked and wheeled agricultural tractors, the European Regulation 167/2013 has to be considered and the approval test for heating, cooling and conditioning systems requires experimental measures according to the European Delegated Regulation EU 2015/208. In detail, the heating and cooling devices have to be experimentally tested basing the measurements on the procedure foreseen in the ISO 14269-2:1997 standard, that provides a particular heavy weather conditions, both for summer and winter cases, and for long periods of time. For the mathematical model, the climatic chamber is represented by 5 blocks, and balance equations are written to simulate the systems in both climate conditions. [ABSTRACT FROM AUTHOR]

The Fourier series, Laplace and Fourier transforms are applicable for the solution of parabolic type involutory differential problem with constant or polynomial coefficients. In the present paper, the first and second order of accuracy difference schemes for the numerical solution of the initial boundary value problem for one dimensional parabolic type involutory partial differential equation are presented. Numerical results are given. [ABSTRACT FROM AUTHOR]

In this paper, the dynamics of convergence rate is investigated for the approximations depending on the changes of the stiffness coefficient of the elastic fixation. The results of the numerical analysis show that with increasing of stiffness coefficient (parameter a) of the elastic fixation the radius of convergence of Neumann series increases, and the convergence rate of the approximations to the exact solution accelerates. [ABSTRACT FROM AUTHOR]

In this paper we consider two least-squares methods: the discontinuous Petrov-Galerkin method and a new version of the hybridized discontinuous Petrov-Galerkin method. The aim of this paper is to compute the optimal test functions for these methods in the Babuska-Ihlenburg problem in 1D. The optimal test functions will be computed with respect to the chosen inner product spaces and bilinear forms. We shall show numerical results of h-convergence of the methods. [ABSTRACT FROM AUTHOR]

This paper deals with the simulation of UNS A92024 aluminium alloy cutting processes. In particular, 2D and 3D Finite Element Method (FEM) simulations were carried out in order to estimate cutting forces and chip morphology during turning operations. The material is modelled with two different set of parameters for the Johnson-Cook's (J-C) constitutive equation and a failure Cockroft and Latham's model exploited considers damage. The comparison between the predicted chip morphology and principal cutting forces at varying of J-C parameters and cutting regimes with those experimentally found are presented and discussed. The paper shows the importance of damage criterion in the cutting forces, during the simulation, especially in 3D. [ABSTRACT FROM AUTHOR]

The differential eigenvalue problem describing eigenvibrations of a simply supported beam with an attached load is investigated. This problem has an increasing sequence of positive simple eigenvalues with a limit point at infinity. To the sequence of eigenvalues, there corresponds a complete orthonormal system of eigenfunctions. We formulate a limit differential eigenvalue problem and prove the convergence of the eigenvalues and eigenfunctions of the initial problem to the corresponding eigenvalues and eigenfunctions of the limit problem as load mass tending to infinity. The original differential eigenvalue problem is approximated by the finite difference method on a uniform grid. Error estimates for approximate eigenvalues and eigenfunctions are established. The theoretical results are illustrated by numerical experiments for a model problem. Investigations of this paper can be extended to the cases of more complicated and important problems on eigenvibrations of plates and shells with attached loads. [ABSTRACT FROM AUTHOR]

The nonlinear second-order differential eigenvalue problem describing eigenvibrations of a bar with elastically attached load is investigated. The existence of an increasing sequence of positive simple eigenvalues with a limit point at infinity is established. To the sequence of eigenvalues, there corresponds a system of normalized eigenfunctions. The initial nonlinear differential eigenvalue problem is approximated by the finite element method on a uniform grid. The accuracy of approximate solutions is studied. The investigations in the present paper can be extended to the cases of more complicated and important problems on eigenvibrations of beams, plates, and shells with elastically attached loads. [ABSTRACT FROM AUTHOR]

The paper proposes an approach to determining the boundary of possible impact loads for a gasturbine locomotive cab involved in the collision with an obstacle, which would allow the cab to retain its necessary durability. This boundary defines the region of safe operation for the locomotive cab considering various parameters of locomotive movement. If the parameters of the movement and the obstacle lie within the region, the safety of personnel and equipment in the cab will be provided. [ABSTRACT FROM AUTHOR]

We give an interpretation of some recent results of Petrova for the Duffing equation ẍ(t) + δẋ(t) + αx(t) + βx³(t) = u(t). The common assumptions are that α, β and δ are positive constants and u(t) ∈ C([T, ∞); R), is a given function, T is a large enough constant. We apply MATLAB/Simulink and compare numerical results with these one of Petrova for the distributions of the zeros of the equation. In this paper, numerical results are given for the case, where β = 0, which situation corresponds to the linear case. [ABSTRACT FROM AUTHOR]

In this paper, some elements of the theory of the Wright function φ are discussed. The Wright function-along with the Mittag-Leffler function-plays a prominent role in the theory of the partial differential equations of the fractional order that are actively used nowadays for modeling of many phenomena including e.g. the anomalous diffusion processes or in the theory of the complex systems. This function appears there simultaneously as a Green function in the initial-value problems for the model linear equations with the constant coefficients and as a special solution invariant under the groups of the scaling transformations of the fractional differential equations. In this paper, both of these applications are shortly introduced. Whereas the analytical theory of the Wright function is already more or less well developed, its numerical evaluation is still an area of the active research. In this paper, the numerical evaluation of the Wright function is discussed with a focus on the case of the real axis that is very important for applications. In particular, several approaches are presented including the method of series summation, integral representations, and asymptotical expansions. In different parts of the complex plane different numerical techniques are employed. In each case, estimates for accuracy of the computations are provided. [ABSTRACT FROM AUTHOR]

The adjoint method is usually used to identify uncertain parameters in large-scale shallow water flow models. This requires the implementation of the adjoint model, which is huge programming effort. The work presented in this paper is based on stochastic simultaneous perturbation of all model parameters to generate a search direction and avoids the implementation of the adjoint of the original nonlinear model. The SPSA based calibration approach has been implemented for the estimation of the depth values in a shallow sea model of the entire European continental shelf. The results demonstrate that the SPSA method give comparable results to steepest descent method with little computational cost. [ABSTRACT FROM AUTHOR]

The paper proposes a numerical investigation based on RANS computation for solving the viscous flow around a ship podded propulsion unit. A set of computations has been performed to better understand the influences exerted by different configurations on the wake structure in the propeller disk in the pushing type case. The RANS computation method is employed to evaluate the flow field structure around the podded propulsion units and the forces acting on it. Hydrodynamic design podded system has not, so far, been fully established in the propeller-pod-strut system. It is necessary to use a reliable procedure in the design of such propulsion systems to increase the propulsion efficiency. In an attempt to meet these needs, the present paper introduces a numerical procedure to analyze the hydrodynamic performance of the propeller and steering system using a combined lifting line and RANS methods. [ABSTRACT FROM AUTHOR]

This paper deals with stability in the numerical solution of general one-dimensional partial differential equations with variable coefficients. We will generalize stability results for central finite difference schemes on non-uniform grids that were obtained by In’t Hout & Volders (2009) for the Black-Scholes equation. Subsequently we will apply our stability results to the CEV model. [ABSTRACT FROM AUTHOR]

The vehicle bogies of Shanghai metro line 1 began to crack just in the third year after the trains operated. More than 50 cracks occurred in the succeeding six year during the train operation. This paper evaluated the safety of the motorized bogies. First, the loading conditions imposed on the vehicle structure were calculated based on the measured data in service of the train, and compared with the original design load. Then, this paper calculated simulated the stress of the vehicle bogie by 3D FEM, and presented the distribution of every stress concentration point in Goodman fatigue diagram. The computational locations of the strength less than the safety are agreed with where cracks have happened. Finally, this paper calculated the fatigue life of the motor bracket of the bogie through S-N curve based on revised Miner theory. In conclusion, this paper think that the bogie cracks of Shanghai metro line 1 are contributed by the overburden fatigue load, and ignoring the lateral vibration load in the design of the vehicle bogie is the important cause that bogie cracks occurred far earlier than in the designed time. [ABSTRACT FROM AUTHOR]

This paper presents a new fast multipole boundary element method (FMBEM) for multiple scattering analyses in time-domain. The conventional time-domain BEM has two disadvantages: 1) The numerical instability in time stepping procedure, and 2) much computational time and memory. Our proposed method overcomes these two disadvantages using the convolution quadrature method for 1) and the fast multipole method for 2). As numerical examples, the large-scale multiple scattering of SH waves by many inclusions is conducted by the proposed method in this paper. [ABSTRACT FROM AUTHOR]

This paper presents numerical simulation results of the deformation and breakup of an isolated liquid drop suspended in an ambient, immiscible viscous fluid under shear flow. The model predicting the dynamic behavior of the drop is based on a diffuse interface method. The interface between the two fluids is tracked by an order parameter, namely the mass concentration. The fully transient, three dimensional Navier-Stokes equations for an incompressible fluid are solved by a projection method on a fixed Cartesian grid which the interface moves through to ensure accurate calculation of the surface evolution. Surface tension effects are incorporated into the model through a modified stress. This paper focuses on steady shape analysis and the end pinching mechanism of drop breakup. The numerical results of drop deformation and breakup show very good agreement with theoretical analysis and experimental observations, which indicate that the diffuse interface method can successfully capture the main behavior of the drop deformation and breakup Detailed instructions for typing your article are given in the following. [ABSTRACT FROM AUTHOR]

J. M. Franco proposed Adapted Runge-Kutta-Nyström (ARKN) methods and derived the sufficient order conditions as well as the necessary and sufficient order conditions for the perturbed oscillators in the one-dimensional case [J. M. Franco, Runge-Kutta-Nyström methods adapted to the numerical integration of perturbed oscillators, Computer Physics Communications 147 (2002): 770-787]. Unfortunately, some mistakes have been made in the order conditions as well as in the derivation of those conditions in that paper. According to the results of that paper, Franco gave some methods of the ARKN-type for systems where the perturbed function f does not depend on the first derivative y′ [J. M. Franco, New methods for oscillatory systems based on ARKN methods, Applied Numerical Mathematics 56 (2006), 1040-1053]. In this paper, we present the multidimensional ARKN methods for the general systems of perturbed oscillators where the perturbed function f may depend on only y or on both y and y′, and derive their order conditions. [ABSTRACT FROM AUTHOR]

In recent years, intensive research has been done at the Brno University of Technology Faculty of Information Technology Department of Intelligent Systems in the field of numerical solutions of systems of ordinary and partial differential equations. The basic numerical method employed is the so-called Modern Taylor Series Method (MTSM). It has been described, studied, and numerous aspects have been investigated such as processing in parallel systems. Also a simulation system TKSL has been developed which is based on the Taylor series method. For some results see [1], [2]. Although there have been considerable practical results, theoretical issues are yet to be investigated since the underlying method has been devised by analogy with analogue solvers of such systems. In this paper we provide only a basic idea of a theoretical background. The MTSM is based on a transformation of the initial problem into another initial problem with polynomials on the right-hand sides. This is a precondition for a Taylor series method to be successfully applied to the task of finding a numerical solution. The solution of the transformed initial problem then includes the solution of the original original system. A transformation similar to that described in this paper can be found in [3]. Practical aspects are discussed in [4], and [1]. An outline of the special type transformations for functions commonly encountered in initial problems can be found in [5]. The MTSM uses various types of recurrent formulae that can be used to calculate the Taylor series terms of the unknown functions. They include the detection of polynomial solutions.Another type of recurrent formulae clears the way for parallel programs to be used for solving. This type might also be of some interest for further research since it defines another type of initial problem where the right-hand sides include only powers of unknown functions. [ABSTRACT FROM AUTHOR]

In this paper, we propose a complex variable boundary element method for two-dimensional potential problems with one-dimensional periodicity. In the presented method, we reduce the potential problem of interest to the boundary integral equation problem for a complex analytic function where an extension of Cauchy’s integral formula for periodic analytic functions is regarded as a Fredholm integral equation and, by solving a discretized equation of the boundary integral equation, we obtain an approximate solution. Numerical examples are also included. [ABSTRACT FROM AUTHOR]

In this paper a numerical investigation has been carried out to define average Nusselt number on a convex heated curved surface entry of an adiabatic channel. For channels with a convex heated surface, where the increase in flow cross sectional area decelerates the flow (adverse pressure gradient) while buoyancy accelerates the flow, separation is observed near the heated surface. The effects of Reynolds number, Grashof number, and separation on average Nusselt number is discussed for a fixed value of R/L. [ABSTRACT FROM AUTHOR]

For a widespread application of dissipative braces to protect framed buildings against seismic loads, practical and reliable design procedures are needed. In this paper a design procedure based on the Direct Displacement-Based Design approach is adopted, assuming the elastic lateral storey-stiffness of the damped braces proportional to that of the unbraced frame. To check the effectiveness of the design procedure, presented in an associate paper, a six-storey reinforced concrete plane frame, representative of a medium-rise symmetric framed building, is considered as primary test structure; this structure, designed in a medium-risk region, is supposed to be retrofitted as in a high-risk region, by insertion of diagonal braces equipped with hysteretic dampers. A numerical investigation is carried out to study the nonlinear static and dynamic responses of the primary and the damped braced test structures, using step-by-step procedures described in the associate paper mentioned above; the behaviour of frame members and hysteretic dampers is idealized by bilinear models. Real and artificial accelerograms, matching EC8 response spectrum for a medium soil class, are considered for dynamic analyses. [ABSTRACT FROM AUTHOR]

Probabilistic fracture analyses are performed for investigating uncertain fracture response of Functionally Graded Material (FGM) structures. The First-Order-Reliability-Method (FORM) is implemented into an existing Finite Element code for FGM (FE-FGM), which was previously developed at the University of Illinois at Urbana-Champaign [2]. The computational simulation will be used in order to estimate the probability of crack initiation with uncertainties in the material properties only. The two-step probability analysis method proposed in the companion paper (Part I, [1]) is illustrated by a numerical example of a composite strip with an edge crack. First, the reliability index of a crack initiation event is estimated as we vary the mean and standard deviation of the slope and the location of the inflection point of the spatial profile of Young's modulus. Secondly, the reliability index is estimated as we vary the standard deviation and the correlation length of the random field that characterize the random spatial fluctuation of Young's modulus. Also investigated is the relative importance of the uncertainties in the toughness compared to those in Young's modulus. [ABSTRACT FROM AUTHOR]

Conjugate gradient (CG) methods have been recognized as an interesting technique to solve optimization problems, due to the numerical efficiency, simplicity and low memory requirements. In this paper, we propose a new CG method based on the study of Rivaie et al. [7] (Comparative study of conjugate gradient coefficient for unconstrained Optimization, Aus. J. Bas. Appl. Sci. 5(2011) 947-951). Then, we show that our method satisfies sufficient descent condition and converges globally with exact line search. Numerical results show that our proposed method is efficient for given standard test problems, compare to other existing CG methods. [ABSTRACT FROM AUTHOR]

Recently many researches try to develop and improve the Conjugate Gradient (CG) methods because of its convergence properties and low computation costing. In this paper, another CG coefficient (.k) will be proposed which is categorized as modification in such a way to improve the performance of the classical CG methods. This paper is focused on generating (.k) with several desirable properties: (1) generate descent search direction at each iterations; and (2) converge globally by using strong Wolfe line search. Numerical comparisons of three CG methods show the robustness and the efficiency of the new method in solving all given problems. [ABSTRACT FROM AUTHOR]

This paper considers Newton-MSOR iterative method for solving 1D nonlinear porous medium equation (PME). The basic concept of proposed iterative method is derived from a combination of one step nonlinear iterative method which known as Newton method with Modified Successive Over Relaxation (MSOR) method. The reliability of Newton-MSOR to obtain approximate solution for several PME problems is compared with Newton-Gauss-Seidel (Newton-GS) and Newton-Successive Over Relaxation (Newton-SOR). In this paper, the formulation and implementation of these three iterative methods have also been presented. From four examples of PME problems, numerical results showed that Newton-MSOR method requires lesser number of iterations and computational time as compared with Newton-GS and Newton-SOR methods. [ABSTRACT FROM AUTHOR]

This paper deals with the mathematical model of a steady flow of a heat-conductive incompressible viscous fluid through a spatially periodic plane profile cascade. The corresponding boundary value problem is reduced to one spatial period. We prove the existence of a weak solution of a coupled problem, with various boundary conditions on the parts of the boundary. Particularly, the condition on the outflow is a variant of the so called "do nothing" boundary condition. [ABSTRACT FROM AUTHOR]

A disk Bézier curve is a Bézier curve whose control points are disks. It can be considered as a parametric curve with error tolerances. In this paper, we propose method to find G2-multi degree reduction of disk Bézier curves based on two stages. The center and the radius curves are degree reduced using G2-continuity in the first stage and minimizing the error of approximating the radius curve in the second stage. We give some examples and figures to demonstrate the efficiency of the method. [ABSTRACT FROM AUTHOR]

In this paper, we established some new integral inequalities of Hadamard-type for co-ordinated convex functions by using a new integral identity and fairly elementary analysis. [ABSTRACT FROM AUTHOR]

A European call option price formula under the BS-BHM-Updated model is studied in this paper. BS-BHMUpdated model is a BS-BHM model improved in applying Gaussian integral. The formula of European call and put options price is given in this paper too. Greeks and a good property of put-call parity for the formula of European call option price are found. In this paper are also given the numerical results of European call option price and the put-call parity relationship. Numerical results of European call option price under BS-BHM-Updated model, Black Scholes model, and BS-BHM model are presented. [ABSTRACT FROM AUTHOR]

Alternative current field measurement (ACFM) and eddy current thermography are both induced by eddy currents, and it is a commonality between them. The commonality has laid a good foundation for the combination of the two testing techniques. In this paper, a numerical study on distribution law of magnetic field and temperature field around the crack using eddy current excitation is carried out. The feasibility of the combination of ACFM and eddy current thermography is discussed as well. A specimen made of ferromagnetic material is tested by a U-shaped inducer, and a semielliptical crack is built on the specimen. The distribution law of magnetic field and temperature field is both studied using the same eddy current excitation. The relationship between the crack size and distribution of magnetic field and temperature field is identified by altering the length and depth of the crack. Through comparisons, the magnetic distribution law around the crack in this paper is consistent with that of ACFM, and the maximum temperature difference around the crack meets the inspection requirement of a thermal imager. These findings might make it possible to eventually combine ACFM and eddy current thermography. [ABSTRACT FROM AUTHOR]

Pre-impregnated materials (Prepregs) have greatly impacted many industries that require specific advanced composites, such as aerospace structures for UAVs. Prepreg material aids the structure by reducing weight while increasing strength and allowing for reasonably consistent manufacture. One of the most essential features of these materials is the variation in properties as the orientation of the layer changes. This requires the use of advanced techniques for strength analysis, including numerical modelling and material testing. This paper presents an experimental evaluation approach to estimate the mechanical properties of composite shells, including cutting schemes, specimen preparation, and test procedures. In the next stage, this study discusses the use of ABAQUS FEA to replicate the phenomenon of specimen failure modes. The investigated prepreg specimens in this study were created using XC 130 unidirectional easy composite prepreg. Through this research, the failure mode results of testing and numerical analysis showed a good agreement. [ABSTRACT FROM AUTHOR]

The paper deals with the determination of the rotational stiffness of a timber semi-rigid joint. The rotational stiffness was calculated on the basis of the currently valid standard, experimental test and numerical model. The connection was made of a standard combination of bolts and dowels, which consisted of 10 pieces of fasteners with a diameter of 8 mm. The elements of the connection consisted of facades and two struts with a cross-section of 100x300 mm. The connection was then statically repeatedly loaded and relieved. The loading took place up to the level of the ultimate limit state and the unloading up to 10% of the maximum value. In order to determine the actual mechanical properties of timber and fasteners, partial tests were performed for the needs of numerical modelling. [ABSTRACT FROM AUTHOR]

Members of open double-symmetrical cross-sections are widely used in steel structures. In many cases their webs are subjected to transverse compression resulting from the effect of adjacent members or from the concentrated transverse loads. Resistance of the member web to transverse compression is affected by number of aspects, e.g. structural solution of the joint (welded or bolted with end plate), possible longitudinal normal stress in the member caused by axial load or bending moment, interaction with shear or effect of local buckling of the web. The paper focuses on specific problem of resistance of the web to transverse compression resulting from transverse load applied close to the unstiffened end of the member. The investigation of the resistance of the web to transverse compression is performed using advanced geometrically and materially nonlinear numerical analysis for various distances of the transverse load from the unstiffened end. The influence of this distance on transverse compression resistance is quantified. Rolled and welded cross-sections of various web slenderness are investigated. The results are, where possible, compared with results obtained from available design standards. [ABSTRACT FROM AUTHOR]

In this paper the numerical investigations concerning static response of a different configurations of concrete columns subjected to Euler's load are presented. An original approach of connecting the column and pocket footing via steel cut-off pyramid heads is presented. As shown in other works the main difference between conventional planar ended column and the column ended with cut-off pyramid shape is the axial force redistribution at the connection. In the case of standard connection, the compressive force is transferred onto foundation and consequently from the point of connection that force is distributed outwardly with 45° degrees' incline angle onto the ground. With the presented cut-off pyramid connection, one makes possible to reduce foundation height as a result of transferring on footing and consequently to the ground only a part of the compressive force, whereas remaining amount of force is converted into tensile stress effectively taken over by steel reinforcement. A comparative numerical analysis using SolidWorks FEM based software between standard and proposed solution is performed taking into account columns' critical load and Misses-Hencky stress (MHS) redistribution near the columns' head. On the basis of presented results, both solutions advantages and disadvantages are emphasized. [ABSTRACT FROM AUTHOR]

Air pollution from automobiles both commercial and passenger vehicles push the research to make changes in catalytic convertor. Most of the commercial vehicles like coal transport and mineral transport trucks relay on diesel fuel. As a result, the emission levels of carbon monoxide (CO), unburned hydrocarbons (HC), and nitrogen oxides (NOx) are taken into account. As a result of incomplete combustion, alcohols, aldehydes, and other partial oxidation products are released into the air. The whole process of this research work is done with the help of CFD approach because it will reduce the material waste and we can optimize according to our desired results. During this project, a numerical study has been carried out on the catalytic converter by varying the coating materials. Magnesium Oxide (MgO) and Platinum with Palladium was selected as coating materials. For comparison purpose, normal catalytic converter without coating was analyzed using CFD software. Different output characteristics of a catalytic converter like, velocity, static temperature and turbulent kinetic energywere compared with each other. Outcomes of the numerical analysis shows that the catalytic converter which is coated with Magnesium Oxide (MgO) particles coated catalytic converter yields the better performance behavior than that of normal, Platinum and Palladium particles coated catalytic converter. [ABSTRACT FROM AUTHOR]

This paper arose from the teaching of Models in Biology to take a new approach to problems they are familiar with, to come up with an articulate verbal model after a mental effort, to express it in rigorous mathematical terms, to solve corre-sponding equations (with the help of computers), and to analyze and interpret experimental data in terms of their (mathematical) models. We will investigate a mathematical model of branching by solving a system of partial equations (PDEs). The results will describe the success or failure of the growth of the fungus species studied, and we used some codes (pplane7, Pdepe) in numerical analysis because direct mathematical solution was difficult. [5] Tip death due to hyphal death, dichotomous branch-ing [ABSTRACT FROM AUTHOR]

The paper presents two-dimensional model of gas filtration flow in a porous medium as well as efficient computational algorithm. The analysis of performed numerical calculations showed that when the gas filtration parameters and properties are viewed as functions of pressure, then the studying process can be adequately described as a whole and the numerical results correctly reflect its essence. The results of computer calculations were used to substantiate a decision support system for selecting the operating modes of wells in order to obtain optimal and more economical production routine. Computer calculations demonstrated that the longitudinal-transverse directions scheme in some cases may be more preferable than the locally-one-dimensional method. [ABSTRACT FROM AUTHOR]

In recent papers researchers describe some of the new types of properties characterization of the normal distribu- tion. This paper gives a new one based on the characterization of these properties, the proof of the classical limit theorem Lindeberg-Feller. [ABSTRACT FROM AUTHOR]

This paper presents the numerical model of the measuring stand - the wind tunnel, in which is fixed the cylinder with cooling inlet oscillating stream. The aim of this work is the juxtaposition and comparison of characteristic values concerning the oscillating turbulent flow around cylinder, obtained from the experiment conducted in the wind tunnel at the Institute of Thermal Machinery, Czestochowa University of Technology with the data obtained as a result of numerical modeling of unsteady flow phenomena with heat transfer processes. Model discussed in this paper was created using a commercial program ANSYS FLUENT, that is used for mathematical modeling of flow and heat transfer processes. The expected outcome of this study is that it is possible in a way that doesn't require large expenditures of time, numerical modeling a similar stand, which greatly facilitated by further research into the very large issue of unsteady flows. [ABSTRACT FROM AUTHOR]

The results of numerical studies on linear and non-linear transverse vibrations control of a two member column subjected to Euler's load by means of piezoceramic element have been presented in this paper. The investigated column is composed of two members. The external member is a single element and the internal one consists of two rods (the one of them is a made of piezoceramic material). The connection of elements of the internal member has been modeled by means of a pin and a rotational spring of stiffness C. The boundary problem has been formulated on the basis of Hamilton's principle. Due to non-linearity of the column, the perturbation method was used to solve the problem. An influence of the residual force generated by the piezoceramic element on natural vibration frequencies, maximum loading and amplitude - vibration frequency relationship have been discussed in this paper. [ABSTRACT FROM AUTHOR]

We discuss the problem of approximating the length of a curve γ in arbitrary euclidean space En, from ε -uniformly sampled reduced data Qm ={qi}mi =0, where γ (ti)=qi. The interpolation knots {ti}mi=0 are assumed in this paper to be unknown (the so-called non-parametric interpolation). We fit Qm with the piecewise-quadratic interpolant γ2 based on the so-called exponential parameterization (depending on parameter λ ∈ [0,1]) which estimates the missing knots {ti}m i=0 ≈ {ti}mi=0. The asymptotic orders βε (λ) for length estimation d(γ) ≈ d(y2) in case of λ = 0 (uniformly guessed knots) read as βε (1) = min{4,3+ε} (see [2]). This paper establishes a more general result holding for all λ ∈ [0,1] and ε -uniform samplings - see Th. 5. More specifically the respective convergence orders amount to βε (1) = min{4,3+ε} (see [2]). This paper establishes a more general result holding for all λ ∈ [0,1] and ε -uniform samplings - see Th. 5. More specifically the respective convergence orders amount to βε (λ) = min{4,4ε} for λ ∈ [0,1). Consequently βε (λ) are independent of λ ∈ [0,1) and the discontinuity in asymptotic orders βε (λ) at λ = 1 occurs, for all ε ∈ (0,1). The full proof of Th. 5 is presented in ICNAAM'14 post-conference journal publication together with more exhaustive relevant experimentation. [ABSTRACT FROM AUTHOR]

This paper describes a quantitative measurement approach within an effective and transparent operational/strategic planning framework at all levels of organization, including individuals by linking objectives, initiatives and measures to one holistic organization's strategy. The author has introduced an original parameter Vindex that numerically represents the level of accomplishment of strategic/operational plans of the entire organization, its different units, and individual members of staff. The V-index provides a transparency of viewing and effective control of plans of the organization at all levels, with hierarchical and non-hierarchical structures. This parameter facilitates process of year-by-year strategic analysis of the success of the organization and its units by managers. For calculating of actual value of the V-index the author has successfully introduced a recurrent computing algorithm for horizontal/vertical alignment processes of the hierarchical strategic and operational planning. [ABSTRACT FROM AUTHOR]

The aim of this paper is to develop numerical methods for solving systems of integral equations with cardinal splines. The unknown functions are expressed as a linear combination of horizontal translations of certain cardinal spline functions with small compact supports. Then a simple system of equations on the coefficients is obtained for the system of integral equations. It is relatively straight forward to solve the system of unknowns and an approximation of the original solution with high accuracy is achieved. Several cardinal splines are used in the paper to enhance the accuracy. The sufficient condition for the existence of the inverse matrix is examined and the convergence rate is investigated. Examples are given to demonstrate the benefits of the methods. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the possible use of control theory, particularly theory on optimal control to derive some numerical methods for unconstrained optimization problems. Based upon this control theory, we derive a Levenberg-Marquardt-like method that guarantees greatest descent in a particular search region. The implementation of this method in its original form requires inversion of a non-sparse matrix or equivalently solving a linear system in every iteration. Thus, an approximation of the proposed method via quasi-Newton update is constructed. Numerical results indicate that the new method is more effective and practical. [ABSTRACT FROM AUTHOR]

In this paper we study the fourth order Boussinesq equation with a single nonlinearity. We rewrite this equation in a Hamiltonian form and present a noncompact finite difference scheme, which preserves the symplectic structure of the initial problem. We construct a new finite difference scheme, which is very similar to the symplectic scheme but preserves the discrete energy exactly. To illustrate both schemes we present many computational results. We compare the performance of the symplectic scheme with the new conservative finite difference scheme. [ABSTRACT FROM AUTHOR]