optimum sample size is an essential component of any research. the main purpose of the sample size calculation is to determine the enough number of units needed to detect the unknown clinical parameters or the treatment effects or the association after data gathering. it is not uncommon for studies to be underpowered and failing to detect the existed treatment effects due to inadequate sample s...

electrosynthesis process has been used for preparation of zinc sulfide nanoparticles. zinc sulfide nanoparticles in different size and shapes were electrodeposited by electrolysis of zinc plate as anode in sodium sulfide solution. effects of several reaction variables, such as electrolysis voltage, sulfide ion concentration as reactant, stirring rate of electrolyte solution and temperature on p...

We create a practical method to set the segment size of the Welch FFT for wideband and long-term spectrum usage measurements in the context of hierarchical dynamic spectrum access (DSA). An energy detector (ED) based on the Welch FFT can be used to detect the presence or absence of primary user (PU) signal and to estimate the duty cycle (DC). In signal detection with the Welch FFT, segment size...

in this study, aluminium2024- graphite composites containing 5, 10, 15 and 20 weight percent of graphite were produced by solid assisted melt disintegration (samd) technique which resulted in production of al/gr powder mixtures which subsequently consolidated and sintered for preparation of al/gr composites. in this technique, powder mixture was prepared by addition of flake graphite (mean diam...