We present a new approach to evaluating combinatorial sums by using finite differences. Let {ak}k=0 and {bk}k=0 be sequences with the property that ∆bk = ak for k ≥ 0. Let gn = ∑n k=0 ( n k ) ak, and let hn = ∑n k=0 ( n k ) bk. We derive expressions for gn in terms of hn and for hn in terms of gn. We then extend our approach to handle binomial sums of the form ∑n k=0 ( n k ) (−1)ak, ∑ k ( n 2k ...

In this talk we consider the finite element discretization of the Immersed Boundary Method (IBM) introduced by Peskin [6] for fluid-structure interaction problems. With respect to the original finite differences discretization the finite element approach can take advantage from the variational formulation in handling the Dirac delta function which takes into account the presence of the structur...

adequate coverage is one of the main problems for distributed wireless sensor networks and the effectiveness of that highly depends on the sensor deployment scheme. given a finite number of sensors, optimizing the sensor deployment will provide sufficient sensor coverage and save power of sensors for movement to target location to adequate coverage. in this paper, we apply fuzzy logic system to...

In this article we develop a numerical scheme to deal with interfaces between touching numerical grids when solving Schrödinger equation. In order to pass the information among grids we use the values of the fields only at the contact point between them. Surprisingly we obtain a convergent methods which is third order accurate with respect to the spatial resolution. In test cases, at the minima...

This paper is concerned with the numerical approximation of viability kernels. The method described here provides an alternative approach to the usual viability algorithm. We first consider a characterization of the viability kernel as the value function of a related optimal control problem, and then use a specially relevant numerical scheme for its approximation. Since this value function is d...

an enhamced scheme is introduced for the solution of two dimensional umsteady euler equations. the finite- volume method of jameson et al. is modified by devicing a pnessune sensor in cell flux calculations. then the discretized gorerning equations ane relaxed in time until na steady state is reached. an appropriate model for the artificial dissipation was also employed. several tests wene cond...