Due to the importance of Acer monspessulanum in Iranian mountain forests, a study was carried out to reliably estimate its woody biomass and growing volume via allometric equations. Four transects, five trees in each were chosen randomly. The characteristics of standing trees including: diameter at root collar, height, number of stems and crown width were measured, then trees were finally cut d...

 Seasonal distribution of species composition, cell abundance and biomass of phytoplankton of the Caspian Sea were investigated in 2005. This survey were fulfilled in 6 transects and 26 stations A total of 260 samples were collected during winter to autumn in the southern part of Caspian Sea. Totally, 163 species of phytoplankton were identified (71 species Bacillariophyta, 31 species Chlorophy...

[1] Spatially-distributed forest biomass components are essential to understand carbon cycle and the impact of biomass burning emissions on air quality. We estimated the density of forest biomass components (foliage biomass, branch biomass, and aboveground biomass) at a spatial resolution of 1 km across the Contiguous United States using foliage-based generalized allometric models and Moderate-...

this research was investigated to evaluate growth indices and competitive ability of two wheat ) triticum aestivum l. (cultivars in interference with two species of narrow and broad leaf weeds as two separated experiments based on a randomized complete block design with three replications at agricultural faculty of bu-ali sina university, during 2008-2009. in both experiments, alvand and sayson...

The thermoelectric response of amorphous, semiconducting Y–Ba–Cu–O thin films was investigated by illumination with 150 ps optical pulses at 1064 nm and with a continuous wave at 493 nm ~argon laser!. The measured unbiased voltage response was consistent with pyroelectricity. At high pulse energies, the voltage response saturated due to the saturation of the spontaneous polarization. The pulsed...

The goal of this paper is to explore the power of genetic algorithms, in particular the so called micro genetic algorithms, to solve a challenging problem in experimental physics. The problem is to find an optimum frequency to stabilize atoms by high-intensity laser fields. The standard approach to search for optimal laser parameters has been by trial and error. This is the first known applicat...

From classical charge transport equations and dipole radiation equations, we derive a simple analytical model for the signal detected in terahertz time-domain spectroscopy using photoconducting antennas. The validity of our model is checked by comparison to published calculated results and to experimental data we have measured. This expression depends mostly on the carrier lifetime in the anten...

This paper demonstrates how the extended duration calculus [4] can be used to support the approach to documentation of computer systems presented by in [1]. This approach uses the general concept of mathematical relations to specify properties, while the calculus of durations provides the means to reason about such specifications, and in particular, prove formally that a design implies the requ...