A cone-beam image reconstruction algorithm using spherical harmonic expansions is proposed. The reconstruction algorithm is in the form of a summation of inner products of two discrete arrays of spherical harmonic expansion coefficients at each cone-beam point of acquisition. This form is different from the common filtered backprojection algorithm and the direct Fourier reconstruction algorithm...

Finite-dimensional harmonic models for theH2 norm evaluation of finitedimensional linear continuous-time periodic (FDLCP) systems are derived, which are expressed explicitly through finitely many Fourier coefficients of the system matrices, and thus dispense with the transition matrix knowledge of any FDLCP models, as opposed to most existing methods in the literature. This paper also shows tha...

We investigate the properties of the (complex) coefficients obtained in a spherical harmonic representation of temperature maps of the cosmic microwave background (CMB). We study the effect of the coefficient phase only, as well as the combined effects of phase and amplitude. The method used to check for anomalies is to construct a “random walk” trajectory in the complex plane where the step le...

We provide an efficient algorithm for calculating, at appropriately chosen points on the two-dimensional surface of the unit sphere in R, the values of functions that are specified by their spherical harmonic expansions (a procedure known as the inverse spherical harmonic transform). We also provide an efficient algorithm for calculating the coefficients in the spherical harmonic expansions of ...

Linear time invariant (LTI) systems are widely used for modeling system dynamics in science and engineering problems. Harmonic oscillation of LTI systems are widely used for modeling and analyses of periodic physical phenomenon. This study investigates sufficient conditions to obtain harmonic oscillation for high-order LTI systems. The paper presents a design procedure for controlling harmonic ...

An algorithm is introduced for the rapid evaluation at appropriately chosen nodes on the two-dimensional sphere S2 in R3 of functions specified by their spherical harmonic expansions (known as the inverse spherical harmonic transform), and for the evaluation of the coefficients in spherical harmonic expansions of functions specified by their values at appropriately chosen points on S2 (known as...

Interferometric observation of the CMB polarization can be expressed as a linear sum of spherical harmonic coefficients a±2,lm of the CMB polarization. The linear weight for a±2,lm depends on the observational configuration such as antenna pointing, baseline orientation, and spherical harmonic number l,m. Since an interferometer is sensitive over a finite range of multipoles, a±2,lm in the rang...

The importance of the electric power quality (PQ) demands new methodologies and measurement tools in the power industry for the analysis and measurement of the basic electric magnitudes necessary. This paper presents a new measurement procedure based on neural networks for the estimation of harmonic amplitudes of current/voltage and respective harmonic powers. The measurement scheme is built wi...

In this paper we apply the method developed by Rice [1], of solving for the elastic field of a crack with a front perturbed from some reference shape, to solve the elasticity problems of somewhat circular planar tensile cracks under arbitrary load distributions. The method is based on a known solution for the stress intensity factor along a circular crack due to a pair of wedge-opening point fo...

an elliptical tank cross-section is formulated to explore and optimization method, based on a real-coded genetic algorithm to enhance the roll stability limit of a tank vehicle. a shape genetic algorithm optimization problem is applied to minimize the overturning moment imposed on the vehicle due to c.g. height of the liquid load, and lateral acceleration and cargo load shift . the minimization...