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In this paper, we construct fast discrete transforms of wavelet type with an arbitrary number of zero moments for nonuniform grids. We obtain explicit formulas for the parameters defining the wavelet transform. [ABSTRACT FROM AUTHOR]

In this paper, we study option pricing under a regime-switching exponential Lévy model. Assuming that the coefficients are time-dependent and modulated by a finite state Markov chain, we generalise the work in Momeya and Morales (Method Comput Appl Probab, 2014, doi:), and Siu and Yang (Acta Mathe Appl Sin 2:369-388, 2009), that is, we use a pricing method based on the Esscher transform conditional on the information available on the Markov chain. We also carry out numerical analysis, to show the impact of the risk induced by the underlying Markov chain on the price of the option. [ABSTRACT FROM AUTHOR]

Mesh matching is an effective way to convert the non-conforming interfaces between two hexahedral meshes into conforming ones, which is very important for achieving high-quality finite element analysis. However, the existing mesh matching algorithm is neither efficient nor effective enough to handle complex interfaces and self-intersecting sheets. In this paper, the algorithm is improved in three aspects: (1) by introducing a more precise criteria for chord matching and the concept of partition chord set, complex interfaces with internal loops can be handled more effectively; (2) by proposing a new solution, self-intersecting sheet can be inflated and extracted locally; and (3) by putting forward a mesh quality evaluation method, the sheet extraction operation during mesh matching can be done more efficiently. Our improved mesh matching algorithm is fully automatic, and its effectiveness is demonstrated by several examples in different matching situations. [ABSTRACT FROM AUTHOR]

A strong indication about the existence of a (7 p, 4, 1) difference family with p ≡ 7 (mod 12) a prime has been given in [11]. Here, developing some ideas of that paper, we give, much more generally, a strong indication about the existence of a cyclic ( pq, 4, 1) difference family whenever p and q are primes congruent to 7 (mod 12) and of a cyclic ( pq, 5, 1) difference family whenever p and q are primes congruent to 11 (mod 20). Indeed we give an algorithm for their construction that seems to be always successful and we have checked it works whenever both primes p and q do not exceed 1,000. All our ( pq, 4, 1) and ( pq, 5, 1) difference families have the nice property of admitting a multiplier of order 3 or 5, respectively, that fixes almost all base blocks. As an intermediate result we also find an optimal ( p, 5, 1) optical orthogonal code for every prime p ≡ 11 (mod 20) not exceeding 10,000. [ABSTRACT FROM AUTHOR]

In the present paper, we classify the finite subgroups $G\backslash subset\backslash operatorname\{GL\}\_4(\backslash Bbb\; C)$ such that the quotient $\backslash Bbb\; C^4$ by the action $G$ has only isolated terminal Gorenstein singularities. [ABSTRACT FROM AUTHOR]

A material model based on fiber–fiber Coulomb and viscous friction for connective tissue was introduced in references Mijailovic (1991) and Mijailovic et al. (1993). A numerical procedure was developed in reference Mijailovic (1991) by considering sliding of fibers as a contact problem between bodies, and results were verified by experiments. Another numerical approach, much more stable and efficient, for stress calculation in case of Coulomb friction only, was proposed in reference Kojic et al. (1998). This paper represents an extension of the numerical algorithm of reference Kojic et al. (1998) to include viscous friction between fibers. The complex history of sliding is traced by dividing the current sliding length between fibers on a number of segments. The computational procedure is simple, numerically reliable and provides stress calculation for arbitrary cyclic loading of connective tissue material in tension, shear, and tension and shear simultaneously. Typical hysteresis loops can be reproduced by using the proposed numerical algorithm. The model is implemented into a finite element program PAK (Kojic et al., 1996), with a possibility of solving real problems of connective tissue. Solved examples illustrate the main features of the fiber–fiber kinetics model and of the developed numerical procedure. [ABSTRACT FROM AUTHOR]

Numerical representations of choice functions allow the expression of a problem of choice as a problem of finding maxima of real-valued functions, which requires that less information be defined and which is easier to work with. In this paper, the existence of numerical representations of choice functions by imposing assumptions directly on the choice function is obtained. In particular, it is proved that (IIA) is a necessary and sufficient condition for a choice function to be representable, if the set of alternatives is countable, while the conjunction of (IIA) and a ‘continuity condition’ is sufficient to ensure it in separable topological spaces. [ABSTRACT FROM AUTHOR]

Glazebrook [1] has given an account of improved procedures for strategy evaluation for resource allocation in a stochastic environment. These methods are extended in the paper in such a way that they can be applied to problems which, for example, have precedence constraints and/or an arrivals process of new jobs. Theoretical results, backed up by numerical studies, show that quasi-myopic heuristics often perform well. [ABSTRACT FROM AUTHOR]

In this paper we discuss a general approach to studying asymptotic properties of statistical estimators in stochastic programming. The approach is based on an extended delta method and appears to be particularly suitable for deriving asymptotics of the optimal value of stochastic programs. Asymptotic analysis of the optimal value will be presented in detail. Asymptotic properties of the corresponding optimal solutions are briefly discussed. [ABSTRACT FROM AUTHOR]

This paper develops a new lower bound for single facility location problems with lp distances. We prove that the method produces superior results to other known procedures. The new bound is also computationally efficient. Numerical results are given for a range of examples with varying numbers of existing facilities and p values. [ABSTRACT FROM AUTHOR]

Let p be a prime and let b be a positive integer. If a ( v, k, λ, n) difference set D of order n = p b exists in an abelian group with cyclic Sylow p-subgroup S, then $${p\in\{2,3\}}$$ and | S| = p. Furthermore, either p = 2 and v ≡ λ ≡ 2 (mod 4) or the parameters of D belong to one of four families explicitly determined in our main theorem. [ABSTRACT FROM AUTHOR]

It has been shown that if a ( v, k, λ)-symmetric design with λ ≤ 3 admits a flag-transitive automorphism group G which acts primitively on points, then G must be of affine or almost simple type. Here we extend the result to λ = 4. [ABSTRACT FROM AUTHOR]

We propose a new omnibus test statistic for normality based on the Jarque-Bera test statistic. We give the exact first four moments of the null distribution for the statistic using a computer algebra system. Our proposed statistic is an improvement of Jarque-Bera test statistic. Then the cumulants of the standardized statistic satisfy the Cornish-Fisher assumption. We give a normalizing transformation of the statistic based on the Wilson-Hilferty transformation. [ABSTRACT FROM AUTHOR]

Given a prime p, we consider the dynamical system generated by repeated exponentiations modulo p, that is, by the map $${u \mapsto f_g(u)}$$, where f g( u) ≡ g u (mod p) and 0 ≤ f g( u) ≤ p − 1. This map is in particular used in a number of constructions of cryptographically secure pseudorandom generators. We obtain nontrivial upper bounds on the number of fixed points and short cycles in the above dynamical system. [ABSTRACT FROM AUTHOR]

It is well known that there exists a transversal design TDλ[ k; u] admitting a class regular automorphism group U if and only if there exists a generalized Hadamard matrix GH( u, λ) over U. Note that in this case the resulting transversal design is symmetric by Jungnickel’s result. In this article we define a modified generalized Hadamard matrix and show that transversal designs which are not necessarily symmetric can be constructed from these under a modified condition similar to class regularity even if it admits no class regular automorphism group. [ABSTRACT FROM AUTHOR]

The existence and uniqueness of a slowly oscillating solution to parabolic inverse problems for a type of boundary value problem are established. Stability of the solution is discussed. [ABSTRACT FROM AUTHOR]

The WENO method, RKDG method, RKDG method with original ghost fluid method, and RKDG method with modified ghost fluid method are applied to singlemedium and two-medium air-air, air-liquid compressible flows with high density and pressure ratios. We also provide a numerical comparison and analysis for the above methods. Numerical results show that, compared with the other methods, the RKDG method with modified ghost fluid method can obtain high resolution results and the correct position of the shock, and the computed solutions are converged to the physical solutions as the mesh is refined. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the stability of a new pexider-type functional equation. This functional equation is f1(x+y+z)+f2(x-y)+f3(z-x)f4(x-y-z)-f5(x+y)-f6(x+z) = 0, a mixed of a quadratic and an additive functional equations. It established the generalized Hyers-Ulam-Rassias stability for new pexider-type functional equation on the punctured domain V\ {0} and obtain its general solution from the stability results. It also let V and X be normed space and Banach space, respectively. Results of the applications and stability of the equation are also given.

Events with an isolated high pT lepton, a hadron jet and missing energy as observed in the H1 experiment at HERA, are potentially associated with R-parity violation in supersymmetric theories. However, stringent kinematic constraints must be fulfilled if the production of supersymmetric particles in R-parity violating scenarios were the correct path for explaining these puzzling events. A reference point ℝ/ is specified for which these constraints are illustrated and implications of the supersymmetric interpretation for new classes of multi-lepton events are indicated. [ABSTRACT FROM AUTHOR]

Constitutive equations that describe the experimentally observed failure waves are proposed to model inelastic strains of brittle materials. The complete system of equations is hyperbolic, each equation of this system has divergent form. The model is based on the assumption that continual failure is the process of transition from an intact state to a “fully damaged” state described by the kinetics of the order parameter. The structure of stationary traveling compressive waves is analyzed using a simplified model. It is shown that in a certain range of amplitudes, the wave splits into an elastic precursor and a failure wave. [ABSTRACT FROM AUTHOR]

We propose objectives consisting of two mirrors with central holes for passage of a light beam. The optical layout ensures multiple reflection of rays from both mirrors. We consider several approaches to calculating the design parameters for which three and four aberrations do not occur. The objectives can be used in optical devices operating in the UV and IR regions of the spectrum. [ABSTRACT FROM AUTHOR]

The article presents a discussion that focuses on the two methods of sharpening Jordan's inequality. It is mentioned that the first method conveys the possibility to come up with new strengthened Jordan's inequalities from old ones. On the other hand, it is also said that the second method shows that Jordan's inequality may be sharpened by choosing appropriate functions in the monotone form of L'Hopital's rule. A background of Jordan's inequality is also disclosed. Theorems that support the sharpening of Jordan's inequality are also provided.

The article presents a discussion that focuses on the Kantorovich and the Durrmeyer-type modifications of the generalized favard operators. The discussion is also said to be aimed at proving an inverse approximation theorem for functions f. An analogous inequality for the rth weighted modulus of smoothness of the function f is also presented. The theorems, equations, and calculations associated with such mathematical concept are also included in the discussion. Mathematical proofs linked to such equations are also provided.

The article proposes and examines an iterative algorithm for a finite family of non-expansive mappings T1, T2, …, Tr. The study uses various iterative schemes to examine a common fixed point of a finite family of non-expansive mappings under some type of control conditions. It reveals that the proposed iterative algorithm converges strongly to a common fixed point of T1, T2, …, Tr. The section also provides computations of the problem and explains how they arrived to their conclusion.

We obtain a uniform and sufficient condition for the convergence of the Lagrange interpolation process with Jacobi nodes on a closed interval [ a, b] ⊂ (−1, 1). The condition is stated in terms of the second differences of the interpolated function and uses its values only at the interpolation nodes. Some well-known criteria for uniform convergence are obtained as a consequence of our result. [ABSTRACT FROM AUTHOR]

A semiotic perspective on mathematical activity provides a way of conceptualizing the teaching and learning of mathematics that transcends and encompasses both psychological perspectives focussing exclusively on mental structures and functions, and performance-focussed perspectives concerned only with student' behaviours. Instead it considers the personal appropriation of signs and the underlying meaning structures embodying relationships between signs. It is concerned with patterns of sign use and sign production, including individual creativity in sign use, and the underlying social rules and contexts of sign use. It is based on the concept of a semiotic system, comprising signs, rules of sign production, and an underpinning meaning structure. This theorisation is applied to the learning of number, from counting to calculation. Historical, foundational and developmental (i.e., learning) perspectives are explored and contrasted. It is argued that in each of these domains, the dominant significant activity concerns the production of sequences of signs. [ABSTRACT FROM AUTHOR]

The algebras of derivations of naturally graded Leibniz algebras are described. The existence of characteristically nilpotent Leibniz algebras in any dimension greater than 4 is proved. [ABSTRACT FROM AUTHOR]

We study the problem of the attractors of the boundary-value problem $u\_t=\backslash sqrt\; \backslash varepsilon\; (D\_0\; +\; \backslash sqrt\; \backslash varepsilon\; D\_1)\backslash Delta\; u\; +\; (A\_0\; +\; \backslash varepsilon\; A\_1)u\; +\; F(u),\backslash qquad\; u\_x|\_\{x=0,\backslash ,\backslash ,\; x=l\_1\}\; =\; u\_y|\_\{y=0,\backslash ,\backslash ,\; y=l\_2\}=0,$ where $0\; \backslash le\; \backslash varepsilon\; \backslash ll\; \backslash nomathbreak\; 1$, $u\backslash in\; \backslash Bbb\{R\}^N$, $N\backslash ge\; \backslash nomathbreak\; 3$, ~$\backslash Delta$ is the Laplace operator, and $-D\_0$ is the Hurwitz matrix. For such a boundary-value problem, under certain assumptions, we establish the existence of any finite fixed number of stable cycles, provided that $\backslash varepsilon\; >\; \backslash nomathbreak\; 0$ is chosen appropriately small. In other words, it is shown that this boundary-value problem involves the buffer phenomenon. [ABSTRACT FROM AUTHOR]

It is shown that, except for several explicitly described cases, two hyperbolic tube domains in $\backslash CC^2$ are biholomorphically equivalent if and only if they are affinely equivalent. [ABSTRACT FROM AUTHOR]

For $N=\; 2^s$, in the space of complex-valued $N$-periodic functions of an integer argument, we construct $s$ orthogonal bases such that the elements of the $r$th basis, where $r\backslash in\backslash \; 1,\backslash dots,s\backslash$, take $2^r$ values of uniformly distributed on the unit circle in the complex plane. [ABSTRACT FROM AUTHOR]

We classify purely log-terminal blow-ups of index $1$ of three-dimensional terminal singularities. [ABSTRACT FROM AUTHOR]

We obtain necessary and sufficient conditions for the Lipschitzian invertibility of the differential mapping $d/dt-\; \backslash nomathbreak\; f$, where $f\backslash :\{\backslash Bbb\; R\}\backslash to\{\backslash Bbb\; R\}$ is a continuous mapping, in the spaces $L\_p(\{\backslash Bbb\; R\},\{\backslash Bbb\; R\})$, $1\backslash le\; p\backslash le\; \backslash nomathbreak\; \backslash infty$. [ABSTRACT FROM AUTHOR]

We present a semi-analytical approach for three-dimensional elastostatic normal contact problems with friction. The numerical approach to iteration on contact area and stick zone size is supported by an underlying analytical solution relating normal and tangential surface tractions to surface displacements in three coordinate directions. The governing equations are fully coupled. The analytical surface displacement solutions for a basic loading element have been derived elsewhere (Li and Berger 2001), and the total surface displacements are constructed as a superposition of deflections due to overlapping pyramid load segments. This approach requires no interpolation scheme for the field variables, which distinguishes it from other numerical techniques such as the FEM, BEM, and meshless methods. A background grid is defined only on the contact surfaces, and iteration approaches are used to determine a convergent configuration for contact domain and stick zone size. The approach is exercised on several normal contact problems, with and without friction, and the results compare favorably to existing analytical and numerical solutions. [ABSTRACT FROM AUTHOR]

The formulation of a nonlinear composite shell element is presented for the solution of stability problems of composite plates and shells. The formulation of the geometrical stiffness presented here is exactly defined on the midsurface and is efficient for analyzing stability problems of thin and thick laminated plates and shells by incorporating bending moment and transverse shear resultant forces. The composite element is free of both membrane and shear locking behaviour by using the assumed natural strain method such that the element performs very well as thin shells. The transverse shear stiffness is defined by an equilibrium approach instead of using the shear correction factor. The proposed formulation is computationally efficient and the test results showed good agreement. In addition the effect of the viscoelastic material is investigated on the postbuckling behaviour of laminated composite shells. [ABSTRACT FROM AUTHOR]

Deformation behavior of soft-matrix two-phase alloys has been computed using a continuum mechanics model based on an Isostrain condition, while the stress is distributed by the rule of mixtures. A genetic algorithm (GA) was used to optimize the mechanical modeling parameters such as the resistance and the formability of each phase. The stress–strain curves have been calculated as a function of volume fraction and mechanical properties of phases. The calculated and experimental stress–strain curves are compared and good agreement is found. The resistances increases with the rise of the hard phase volume fraction; this is more important with the presence of the hard phase than with the soft one. A linear law of variation of the phase resistance allows to interpolate and extrapolate the model, a good agreement is found with the evolution of the mechanical behavior. [ABSTRACT FROM AUTHOR]

Estimation of the frequency and spatial dependent boundary traction vector from measured vibration responses in a vibrating structure is addressed. This problem, also referred to as the inverse problem, may in some circumstances be ill-conditioned. Here a technique to overcome the ill-conditioning is proposed. A subset of a set of available eigenmodes is chosen such that the problem becomes well-conditioned enough. It is shown that the ill-conditioning originates from the fact that not all eigenmodes are orthogonal over the surface where the traction vector is sought. Consequently, by choosing a set of eigenmodes orthogonal over the surface of interest, the problem becomes well-conditioned. The calculated traction vector is shown to converge to the true one in the sense of a L2-norm on the boundary of the body. The proposed technique is verified, using numerical simulation of measured responses, with good agreement. [ABSTRACT FROM AUTHOR]

The exact analytical solution of a nonlinear boundary-value problem is used to study the effect of a generalized geometric parameter, which characterizes thickness and curvature, on the subcritical and postcritical deformation of a hinged infinite noncircular cylindrical shell. The load on the shell is nonuniformly distributed over its cross section. The deflection of the shell is plotted for various values of the geometric parameter [ABSTRACT FROM AUTHOR]

A dual problem is developed for the constrained multifacility minisum location problems involving mixed norms. General optimality conditions are also obtained providing new algorithms based on the concept of partial inverse of a multifunction. These algorithms which are decomposition methods, generate sequences globally converging to a primal and a dual solution respectively. Numerical results are reported. [ABSTRACT FROM AUTHOR]