The algebraic code excited linear prediction (ACELP) algorithm has been adopted by many speech coding standards, due to low complexity and high quality in its analysis-by-synthesis optimization. One of the optimum ACELP codebook search methods is depth first tree search. Two methods based on pulse replacement and pruning of tree are already proposed for improvement the depth first tree search m...

Currently, the cellphone industry is moving towards an integrated CMOS solution for power amplifiers. Cheaper phones for consumers and better bottom lines for companies are the result of this. The goal of this thesis is to investigate the use of pulse width modulation in a high efficiency integrated CMOS power amplifier for a wireless application. Though high efficiency CMOS power amplifiers ex...

OBJECTIVE Electroporation is the most common method used for the transfection of DNA. Although this method has been attributed for various cell using different buffer compositions, the effects of DNA concentration on the transfection efficiency has not yet been studied. Here the correlation between the efficiency of electroporation reaction and increments of DNA concentration has been investiga...

Measurements of net photosynthesis show that in Phaseolus vulgaris L. the cultivar Michelite-62 exceeds the cultivar Red Kidney in net CO(2) uptake by 23 to 31%. Data on translocation of pulse label indicate that export of a pulse of photosynthetically assimilated (14)C from the source leaf of either M-62 or Red Kidney follows an exponential pattern and shows an initial rapid phase followed by ...

We analyze theoretically the impact of background counts on the efficiency of optical communication in the photonstarved regime using the pulse position modulation (PPM) format with direct detection. Degradation of the photon information efficiency is studied in the case when the background count rate is at most comparable with the rate of photodetection events generated by the incoming optical...

The great difficulty of producing high intensity radiation in the terahertz (THz) spectral region by conventional electronics has stimulated interest in development of sources based on photonics. Optical rectification in lithium niobate is an attractive approach, because it supports high generation efficiencies, uses low cost, bulk LN crystals, and is powered by common Yb-doped lasers at wavele...

In this study we report on the ablation of steel using femtosecond double-pulse trains. Double-pulse trains with pulse-to-pulse separations between 1 ps and 1 ns were used to machine micro-channels in a steel sample. The depths of the laser-ablated channels were measured to characterize the efficiency of the ablation process. Results show that using a double-pulse train with an optimal separati...

High-order harmonic generation in the presence of a chirped THz pulse is investigated numerically with a complete 3D nonadiabatic model. The assisting THz pulse illuminates the high-order harmonic generation gas cell laterally inducing quasi-phase-matching. We demonstrate that it is possible to compensate the phase mismatch during propagation and extend the macroscopic cutoff of a propagated st...

An arbitrary pulse shape by compensating gain saturation in a solid-state Master oscillator power amplifier (MOPA) system made up of three Neodymium doped yttrium vanadate (Nd:YVO4) amplifiers is demonstrated. By investigating the amplifier dynamics in detail, car-shaped pulse shapes were obtained with compensated pulse distortion. Desired pulse shapes, such as multiple-step, square, parabolic,...

In this article, a numerical method based on  improvement of block-pulse functions (IBPFs) is discussed for solving the system of linear Volterra and Fredholm integral equations. By using IBPFs and their operational matrix of integration, such systems can be reduced to a linear system of algebraic equations. An efficient error estimation and associated theorems for the proposed method are also ...