We describe a compact, tunable, optical time-delay module that functions by means of total internal reflection within two glass prisms. The delay is controlled by small mechanical motions of the prisms. The device is inherently extremely broad band, unlike time delay modules based on "slow light" methods. In the prototype device that we fabricated, we obtain time delays as large as 1.45 ns in a...

A numerical method for Riccati equation is presented in this work. The method is based on the replacement of unknown functions through a truncated series of hybrid of block-pulse functions and Chebyshev polynomials. The operational matrices of derivative and product of hybrid functions are presented. These matrices together with the tau method are then utilized to transform the differential equ...

In this paper a unified approach via block-pulse functions (BPFs) or shifted Legendre polynomials (SLPs) is presented to solve the linear-quadratic-Gaussian (LQG) control problem. Also a recursive algorithm is proposed to solve the above problem via BPFs. By using the elegant operational properties of orthogonal functions (BPFs or SLPs) these computationally attractive algorithms are developed....

properties of the hybrid of block-pulse functions and lagrange polynomials based on the legendre-gauss-type points are investigated and utilized to define the composite interpolation operator as an extension of the well-known legendre interpolation operator. the uniqueness and interpolating properties are discussed and the corresponding differentiation matrix is also introduced. the appli...

We demonstrate passive generation of optical pulse trains with each pulse having distinct center carrier and spectra using tunable group delay (GD) staircase transfer functions. The GD steps result from opposite and equal magnitude GD slopes from narrowband and wideband tunable optical dispersion compensators. We use this technique to split the spectrum of a femtosecond pulse to a pulse burst w...

recently, the block-pulse functions (bpfs) are used in solving electromagnetic scattering problem, which are modeled as linear fredholm integral equations (fies) of the second kind. but the theoretical aspect of this method has not fully investigated yet. in this article, in addition to presenting a new approach for solving fie of the second kind, the theory of both methods is investigated as a...

A numerical method for finding the solution of nonlinear VolterraHammerstein integral equations is proposed. The properties of the hybrid functions which consists of block-pulse functions plus rationalized Haar functions are presented. The hybrid functions together with the operational matrices of integration and product are then utilized to reduce the solution of nonlinear Volterra-Hammerstein...

this paper introduces a numerical method for solving the vasicek model by using a stochastic operational matrix based on the triangular functions (tfs) in combination with the collocation method. the method is stated by using conversion the vasicek model to a stochastic nonlinear system of $2m+2$ equations and $2m+2$ unknowns. finally, the error analysis and some numerical examples are provided...

One of the main controlling parameters in diesel engine combustion is the fuel – air mixing process that has direct effects on engine performance and pollutant emissions, reviewing over previous literature showed that split injection strategies could satisfy this purpose very well. For the first time and in this paper, pilot and double injection strategies were combined and formed new triple in...