In this paper, the flexural free vibrations of three dimensional micro beams are investigated based on strain gradient theory. The most general form of the strain gradient theory which contains five higher-order material constants has been applied to the micro beam to take the small-scale effects into account. Having considered the Euler-Bernoulli beam model, governing equations of motion are w...

Filter is one of the main components of embankment dams. By a simple but effective performance, filter protects the dam against erosion and soil scouring in impervious core caused by leakage (piping) and makes it safe. Interaction between filter and erodible base soil is a complex phenomenon which is dependent upon several factors, and has challenged researchers for better understanding the fil...

background: sperm selection for icsi based on morphology and motility might not be relevant to chromatin integrity. thus sperm selection based on sperm characteristics has been suggested. objective: the aim of this study was to compare the efficiency of zeta method with routine density gradient centrifugation method (dgc) for the selection of sperm with higher dna integrity. materials and metho...

in this study it has been tried, to compare results and convergence rate of sensitivity analysis and conjugate gradient algorithms to reduce fuel consumption and increasing engine performance by optimizing the timing of opening and closing valves in xu7/l3 engine. in this study, considering the strength and accuracy of simulation gt-power software in researches on the internal combustion engine...

sperm selection techniques have became an important tool to improve sub fertile ejaculates. the main aim of this study was to assess the dynamics of motile sperm subpopulations of ejaculates from subfertile stallions subjected to density gradient centrifugation (dgc) involving a double layer colloid [dgc2], before and after storage for 24 and 48 hours. ejaculates from eight stallions with ferti...

the degree of aromaticity of mono-substituted derivatives of benzene has beeninvestigated using a new index based on electric field gradient index, by using two mechanicalquantum methods with gaussian 03. two different basis sets have applied to study and theresults compared. this strategy has demonstrated that, due to violation of symmetry in have pisystems,how the degree of aromaticity can ha...

the present study was conducted in the rangeland of glandrood watershed in the province of mazandaran. the objective of this study was to compare between the ecological amplitude of festuca ovina l., and poa bulbosa l., using the function hof along the gradient of the environmental variables. for this purpose 150 plots of 1m2 were established along the altitude gradient. the sampling method was...