In this paper, optimal design of hybrid low damping base isolation and magnetorheological (MR) damper has been studied. Optimal hybrid base isolation system has been designed to minimize the maximum base drift of low damping base isolation system where for solving the optimization problem, genetic algorithm (GA) has been used. In design procedure the maximum acceleration of the structure has ...

introduction: skull base meningiomas constitute a large proportion of the meningiomas, which are the most common benign brain tumors. the treatment of skull base meningiomas is specially challenging and controversial due to the proximity of these tumors to the vital brain structures. radiosurgery is now emerging as an efficient alternative treatment modality which involves the ablation of tumor...

ess the relationship between umbilical cord blood gases at birth and morphology of umbilical cord, in a prospective study of 200 consecutive term delivery, we investigated the relationship between umbilical cord morphology characteristics (umbilical crd length, number of vascular coil, coiling index) and color of amniotic fluid and umbilical vessel blood gases. statistically significant linear ...

in this paper, we used tetranuclear copper (ii) schiff base complexes, [cu4 (μ-sal2hn) (μ-n3)2(n3)2] (1) and [cu4 (μ-salophen) (μ1, 1-n3)2(n3)2] (2), as new precursor in solid-state thermal decomposition for the synthesis of cuo nanoparticles. the crystallinity, purity and morphology of the cuo nanoparticles were characterized by fourier transform infrared (ft-ir), x-ray diffraction (xrd) and s...

in  this  work,  a  new  hybrid  organometallic-inorganic  hybrid nanomaterial was prepared by immobilization of acetyl ferrocene on the  surface  of magnetite  nanoparticles. covalent  grafting of silica coated magnetite nanoparticles (scmnps) with 3-aminopropyl triethoxysilane gave aminopropyl-modified magnetite nanoparticles (ampscmnps). then, schiff base condensation  of ampscmnps with acet...

introduction: notochord. although histologically benign, these tumors are locally aggressiveand present significant managment challenges . there arew some studies onevaluated the location, age and gender of the patients with chordoma in tworeferral centers in tehran.chordoma cases but there was no study about iranian cases. in this study weskull base chordomas are rare neoplasms arising from th...

One the challenging in hardware performance is to designing a high speed calculating unit. The higher of calculations speeds in a computer system  will be pointed out in terms of performance. As a result, designing a high speed calculating unit is of utmost importance. In this paper, we start design whit this knowledge that one multiplier made of several adder and one divider made of several su...