nonconforming discretization of the electric field integral equation for closed perfectly conducting objects galerkin implementations of the method of moments mom of the electric field integral equation efie have been traditionally carried out with divergence conforming sets the normal continuity constraint across edges gives rise to cumbersome implementations around junctions for composite objects and to less accurate implementations of the combined field integral equation cfie for closed sharp edged conductors we present a new mom discretization of the efie for closed conductors based on the nonconforming monopolar rwg set with no continuity across edges this new approach which we call

fast and accurate computation of hypersingular integrals in galerkin surface integral equation formulations via the direct evaluation method hypersingular 4 d integrals arising in the galerkin discretization of surface integral equation formulations are computed by means of the direct evaluation method the proposed scheme extends the basic idea of the singularity cancellation methods usually employed for the regularization of the singular integral kernel by utilizing a series of coordinate transformations combined with a reordering of the integrations the overall algebraic manipulation results in smooth 2 d integrals that can be easily evaluated via standard quadrature rules finally the reduction of the dimensionality of the original integrals together with the smooth behavior of the associated integrands lead up to unmatched accuracy and efficiency

zero entropy dynamical systems with the gluing orbit property abstract under the assumption of the gluing orbit property equivalent conditions to having zero topological entropy are investigated in particular we show that a dynamical system has the gluing orbit property and zero topological entropy if and only if it is minimal and equicontinuous

on the solution of linear and nonlinear integral equation the purpose of this paper is to establish the solution of fredholm volterra integral equation of the second kind in the space l 2 w xc 0 t considering the following when fredholm integral term in li 2 w and volterra integral term in 0 t are linear also each of fredholm or volterra integral term is linear while the other term is nonlinear here w is defined as the domain of integration with respect to position while t is consider as the time email protected 0 t t also the fredholm volterra integral equation of the first kind is established as special case of these work many special in one two and three dimensional problems of integral equation are considered representing the kernel of fredholm integral term in the form of logarithmic function carleman function potential and generalized potential function and macdonald function are considered

observed baseline convergence rates and superconvergence in the scattering cross section obtained from numerical solutions of the mfie the scattering cross section data obtained from numerical solutions of the magnetic field integral equation mfie using a variety of basis functions and both galerkin and non galerkin testing schemes are compared to study the convergence rates of the results for the basis functions considered apparent superconvergence is observed in the mfie scattering cross section when linear tangential linear normal vector basis functions are used with galerkin testing but not with other basis functions

solvability of the infinite system of integral equations in two variables in the sequence spaces c0 and l1 in this article we establish the existence of solution of infinite systems of integral equations in two variables in the sequence spaces c0 and l1 by using meir keeler condensing operators we explain the results with the help of simple examples

existence results for nonlinear integral equations the schauder tychonoff theorem in locally convex topological hausdorff spaces and a nonlinear alternative of leray schauder type are used to establish some existence results for volterra and hammerstein integral equations

a generalization of darbo s theorem with application to the solvability of systems of integral equations in this paper we give an extension of darbo s fixed point theorem associated with measures of noncompactness and present some results on the existence of coupled fixed points for a class of condensing operators in banach spaces moreover as an application we study the problem of existence of solutions for a general system of nonlinear integral equations

metric like spaces to prove existence of solution for nonlinear quadratic integral equation and numerical method to solve it abstract the purpose of this paper is to obtain some common fixed point results for two mappings satisfying various contractive conditions in metric like spaces these results extend some previous results in the literature since the condition under which the operator admits common fixed points is more general than the others in literature therefore several well known results are generalized as an application we use these results to existence of solution for nonlinear quadratic integral equation to credibility we apply modified homotopy and adomian decomposition method to find solution of the above problem with high accuracy

application of simulation function and measure of noncompactness for solvability of nonlinear functional integral equations and introduction to an iteration algorithm to find solution abstract the aim of this article is to investigate the existence of solution for the nonlinear functional integral equations with the help of measure of noncompactness simulation function and generalized darbo fixed point theorem also we provided example for the applicability of obtained results to the theory of integral equations also we introduce an iteration algorithm by modified homotopy perturbation and adomian decomposition method to find solution of the above problem with high accuracy finally we have a discussion about convergence and upper bound of error

on existence and asymptotic stability of solutions of a nonlinear integral equation we prove an existence theorem for a nonlinear integral equation being a volterra counterpart of an integral equation arising in the traffic theory the method used in the proof allows us to obtain additional characterization in terms of asymptotic stability of solutions of an equation in question

the gluing orbit property uniform hyperbolicity and large deviations principles for semiflows abstract we introduce a gluing orbit property weaker than specification for both continuous maps and flows we prove that flows with the c 1 robust gluing orbit property are uniformly hyperbolic and that every uniformly hyperbolic flow satisfies the gluing orbit property we also prove a level 1 large deviations principle and a level 2 large deviations lower bound for semiflows with the gluing orbit property as a consequence we establish a level 1 large deviations principle for hyperbolic flows and every continuous observable and also a level 2 large deviations lower bound finally since many non uniformly hyperbolic flows can be modeled as suspension flows we also provide criteria for such flows to satisfy uniform and non uniform versions of the gluing orbit property

existence of solutions for a class of nonlinear volterra singular integral equations in this paper we prove some results concerning the existence of solutions for a large class of nonlinear volterra singular integral equations in the space c 0 1 consisting of real functions defined and continuous on the interval 0 1 the main tool used in the proof is the concept of a measure of noncompactness we also present some examples of nonlinear singular integral equations of volterra type to show the efficiency of our results moreover we compare our theory with the approach depending on the use of the theory of volterra stieltjes integral equations we also show that the results of the paper are applicable in the study of the so called fractional integral equations which are recently intensively investigated and find numerous applications in describing some real world problems

existence of solution for two dimensional nonlinear fractional integral equation by measure of noncompactness and iterative algorithm to solve it abstract in this article we establish the existence of solution for two dimensional nonlinear fractional integral equation using fixed point theorem and measure of noncompactness applicability of our results is shown by some examples and for validity of the proposed method we make an iterative algorithm by semi analytic technique that finds a closed form of the solution with an acceptable accuracy ability of the proposed method is granted by comparison with another method found in existing literature

comments on the use of curl conforming basis functions for the magnetic field integral equation this paper discusses the author s comments regarding the sentence in the third paragraph of o ergul et al 2005 subsection b in section iii where the authors argue that the diagonal elements of the impedance mom mfie matrices are the same for the implementations of the nxrwg and rwg functions the authors believe that this cannot be stated in general the reply of the authors of o ergul et al 2005 regarding the comment made is also discussed in this paper

on intrinsic ergodicity and weakenings of the specification property abstract since seminal work of bowen 2 it has been known that the specification property implies various useful properties about an expansive topological dynamical system among them uniqueness of the measure of maximal entropy often referred to as intrinsic ergodicity weakenings of the specification property have been defined and profitably applied in various works such as 6 9 11 16 17 it has been an open question see p 798 of 4 whether two of these properties which we here call almost specification and non uniform specification imply intrinsic ergodicity for expansive topological systems we answer this question negatively by exhibiting examples of subshifts with multiple measures of maximal entropy with disjoint support which have non uniform specification with any gap function f n o ln n or almost specification with any mistake function g n 4 we also show some results in the opposite direction showing that subshifts with non uniform specification with gap function f n o ln n or almost specification with mistake function g n 1 cannot have multiple measures of maximal entropy with disjoint support

denseness of intermediate pressures for systems with the climenhaga thompson structures abstract we show that systems with the structure introduced by climenhaga and thompson have dense intermediate pressures and dense intermediate entropies of ergodic measures the result applies to the mane diffeomorphisms

ergodic universality of some topological dynamical systems the krieger generator theorem says that every invertible ergodic measure preserving system with finite measure theoretic entropy can be embedded into a full shift with strictly greater topological entropy we extend krieger s theorem to include toral automorphisms and more generally any topological dynamical system on a compact metric space that satisfies almost weak specification asymptotic entropy expansiveness and the small boundary property as a corollary one obtains a complete solution to a natural generalization of an open problem in halmos s 1956 book regarding an isomorphism invariant that he proposed

on the periodic orbits shadowing and strong transitivity of continuous flows abstract we prove that chaotic flows i e flows that satisfy the shadowing property and have a dense subset of periodic orbits satisfy a reparametrized gluing orbit property similar to the one introduced in bomfim and varandas 2015 in particular these are strongly transitive in balls of uniform radius we also prove that the shadowing property for a flow and a generic time t map and having a dense subset of periodic orbits hold for a c 0 baire generic subset of lipschitz vector fields that generate continuous flows similar results also hold for c 0 generic homeomorphisms and in particular we deduce that chain recurrent classes of c 0 generic homeomorphisms have the gluing orbit property

variational aspects of the reaction in the method of moments the reaction r j sub 1 j sub 2 between two electric surface current densities j sub 1 and j sub 2 is the integral of the dot product of j sub 1 with the electric field produced by j sub 2 jack h richmond see ibid vol 39 no 4 p 473 479 1991 has correctly shown that the reaction is variational a formula is variational if it has a stationary point at the quantity of interest with galerkin s method but is not necessarily variational when the non galerkin element method is applied in the manner where one set of functions is used to expand both j sub 1 and j sub 2 and another set of functions is used to test both the integral equation for j sub 1 and that for j sub 2 in this paper the reaction r j sub 1 j sub 2 is shown to be variational when the non galerkin method is applied in the manner of operation where the set of functions used to expand j sub 2 is the set of functions used to test the integral equation for j sub 1 and the set of functions used to test the integral equation for j sub 2 is the set of functions used to expand j sub 1 hence the manner of operation just described may be more appropriate than richmond s if a variational result is desired a few numerical results are included to compare the performance of both manners of operation

stable discretization of the electric magnetic field integral equation with the taylor orthogonal basis functions we present two new facet oriented discretizations in method of moments mom of the electric magnetic field integral equation emfie with the recently proposed taylor orthogonal to and divergence taylor orthogonal div to basis functions these new schemes which we call stable unlike the recently published divergence to discretization of the emfie which we call standard result in impedance matrices with stable condition number in the very low frequency regime more importantly we show for sharp edged objects of moderately small dimensions that the computed rcs with the stable emfie schemes show improved accuracy with respect to the standard emfie scheme the computed rcs for the sharp edged objects tested becomes much closer to the rcs computed with the rwg discretization of the electric field integral equation efie which is well known to provide good rcs accuracy in these cases to provide best assessment on the relative performance of the several implementations we have cancelled the main numerical sources of error in the rcs computation i we implement the emfie so that the non null static quasi solenoidal current does not contribute in the far field computation ii we compute with machine precision the strongly singular kernel contributions in the impedance elements with the direct evaluation method

unique equilibrium states for flows and homeomorphisms with non uniform structure abstract using an approach due to bowen franco showed that continuous expansive flows with specification have unique equilibrium states for potentials with the bowen property we show that this conclusion remains true using weaker non uniform versions of specification expansivity and the bowen property we also establish a corresponding result for homeomorphisms in the homeomorphism case we obtain the upper bound from the level 2 large deviations principle for the unique equilibrium state the theory presented in this paper provides the basis for an ongoing program to develop the thermodynamic formalism in partially hyperbolic and non uniformly hyperbolic settings

on the numerical integration of the linear shape functions times the 3 d green s function or its gradient on a plane triangle formulas for the static and dynamic potentials due to linearly varying source distributions defined on a planar triangle are presented the general linear variation of the source is represented in terms of three linear basis functions each one associated with a different vertex of the triangular domain the singular kernels considered are given by the 3 d green s function and its gradient both for the static and dynamic case in the static case the evaluation of potentials is performed analytically and compact form results are given in the dynamic case the results are given in a form suited for numerical integration

applications of measures of noncompactness to the infinite system of differential equations in lp spaces abstract in this paper we apply the technique of measures of noncompactness to the theory of infinite system of differential equations in the banach sequence spaces l p 1 p our aim is to present some existence results for infinite system of differential equations formulated with the help of measures of noncompactness