seismic refraction and downhole survey were employed to study dynamic characteristics of subsurface materials in bam city, southeast of iran. the data acquisition was performed at 160 p and s-wave refraction stations and 15 boreholes in the city. to derive velocity depth sections along these profiles as well as to perform downhole diagrams, seisimager software was used. based on the obtained va...

investigation of projectiles penetration phenomenon has been carried out in non-cohesive soil (sand) targets under dry, saturated and compacted conditions. analytical studies have been performed on the linear and non-linear soil models to obtain penetration depth formulae for ogival nose projectile and the results are verified by experimental studies. in present work, three ogival nose projecti...

A method of visually tracking a known three-dimensional object is described. Predicted object position and orientation extrapolated from previous tracking data are used to find known features in one or more pictures. The measured image positions of the features are used to adjust the estimates of object position, orientation, velocity, and angular velocity in three dimensions, Filtering over ti...

In this work we consider a convolution model for nonlinear conservation laws. Due to the delicate balance between the nonlinear convection and the nonlocal forcing, this model allows for narrower shock layers than those in the viscous Burgers’ equation and yet exhibits the conditional finite time breakdown as in the damped Burgers’ equation. We show the critical threshold phenomenon by presenti...

drying is considered as one of the important stages after plant harvesting which plays an important role in maintaining the quantity and quality of their active ingredients. st. john's wort (hypericum perforatum l.) is an important medicinal plant that high percentages of hypericin in its leaves and flowers are considered as the most important feature of the iranian species. in this resear...

background: the goal of this study was to determine the reliability of tcd in evaluation of vertebrobasilar arteries in comparison with brain mra in patients suffering from acute vertebrobasilar stroke. methods: samples were patients with definite clinical diagnosis of vertebrobasilar stroke. for all patients brain mri, mra and tcd were performed during the first 48 hours of admission. basilar ...