Light-emitting diodes (LEDs) will play a major role in future indoor illumination systems. In general, the generalized Lambertian pattern is widely used as the radiation pattern of a single LED. In this letter, we show that the illuminance distribution due to this Lambertian pattern, when projected onto a horizontal surface such as a floor, can be well approximated by a Gaussian function.

this paper investigates the asymmetry in volatility of returns for the iranian stock market using the daily closing values of the tehran exchange price index (tepix) covering the period from march 25, 2001 to july 25, 2012, with a total of 2743 observations. to this end, two sets of tests have been employed: the first set is based on the residuals derived from a symmetric garch (1,1) model. the...

In this contribution, we address the issue of Blind Source Separation (BSS) in non-Gaussian noise. We propose a twostep approach by combining the fractional lower order statistics (FLOS) for the mixing matrix estimation and minimum entropy criterion for noise-free source components estimation with the gradient-based BSS algorithms in an elegant way. First, we extend the existing gradient algori...

In this paper, a four parameters extension of the generalized Lindley distribution is introduced. The new distribution includes the power Lindley, Lindley, generalized (Stacy) gamma, gamma, Weibull, Rayleigh, exponential and half-normal distribution. Several statistical properties of the distribution are explored. Then, a bivariate version of the proposed distribution is derived. Using a simula...

We have discussed the nonextensive aspects of degree distribution P (k) in Watts-Strogatz (WS) small-world networks by using the three approaches: (a) the maximum-entropy method, (b) hidden-variable distribution and (c) stochastic differential equation. In the method (a), P (k) in complex networks has been obtained by maximizing the nonexten-sive information entropy with the constraint of < k 2...

Noise power spectral density (PSD) estimation is a crucial part of speech enhancement system due to its contributory effect on the quality of the noise reduced speech. A novel estimation method for color noise PSD on the basis of an assumption of generalized Gamma distribution and maximum a posteriori (MAP) criterion is proposed. In the experiment, generalized Gamma PDF which is a natural exten...

In this work we study the distribution function for the total entropy production of a Brownian particle embedded in a non-Markovian thermal bath. The problem is studied in the overdamped approximation of the generalized Langevin equation, which accounts for a friction memory kernel characteristic of a Gaussian colored noise. The problem is studied in two physical situations: (i) when the partic...

We describe the transverse beam distribution in particle accelerators within the controlled, stochastic dynamical scheme of the stochastic mechanics which produces time reversal invariant diffusion processes. In this paper we analyze the consequences of introducing the generalized Student laws, namely non-Gaussian, Lévy infinitely divisible (but not stable) distributions. We will analyze this i...

Cognitive radio arises to be tempting solution to the spectral congestion problem by introducing opportunistic usage of the frequency bands that are not heavily occupied by licensed users. Spectrum sensing plays a crucial role in the cognitive radio technology to prevent damaging interference to the primary users and to reliably and quickly spot the white spaces in the spectrum and utilize the ...