Although most of the wild bee species are ground-nesting, little is known about their nesting requirements and conservation measures to promote ground-nesting bees. Calcareous grasslands one species-rich habitats in Central Europe therefore essential for protecting diversity. The management practices calcareous so far often focused on plant populations, but order support declining insect additi...

successful application of a tbm in a project requires investigating both the ground conditions and the machine and backup system design features. prediction of the machine performance is very important as it has a big effect on the duration of the project and the costs. in this respect, both penetration rate and advance rate must be estimated. utilization factor, which depends on the type of op...

in this research, structural and electronic properties of zncdn-1ten clusters (n=1-10) have been studied by formalism of density functional theory and using the projector augmented wave within local density approximation. the structural properties (such as bond length/angle and coordination number), electronic and optical properties (such as binding energy, kohn-sham spectrum and partial charge...

it is over two decades that groundwater flow models are routinely implemented for better management of groundwater resources.modeling groundwater flow with the help of the ground water modeling system (gms) in the damghan plain aquifer in northern iran,which experiences declining levels and numerous environmental hazards, has demonstrated that, (a) in the worst case scenario theaquifer will fac...

the effect of drought indices on hydrostatic variations and qualitative parameters of the zahedan plain's aquifer was investigated. for this purpose, 12-year statistics from observational and piezometry wells in the plain, the drought index of percentage normal )pn), standardized precipitation index )spi(, and 30-year precipitation statistics of zahedan station were used. results revealed ...

one of the most important challenges in the development of urban railways network is the effects of railway vibrations on human and adjacent structures. although various investigations into the sources of railway vibrations have been conducted, very few research works have been reported on the influences of track geometry parameters on the level of vibrations. this is addressed in this research...

worldwide networks of seismic recording instruments mostly record only translational ground motion in two or three orthogonal directions. rotational component of earthquake is not commonly recorded. several theories are available to estimate a torsional component from recorded translational components of ground motion. in this paper detailed investigations are made to study the relative perform...