how to cite this article: shetty g, avabratha k.s, rai b.s. ring-enhancing lesions in the brain: a diagnostic dilemma. iran j child neurol. 2014 summer;8(3): 61-64. abstract the most common radiological abnormality seen in young indian patients with epilepsy is single small enhancing (ring/disc) computed tomographic (ct) lesions. the two most common differential diagnosis of this lesion in clin...

The dry lubricated bump-type foil air bearing enables a carrying load capacity due to pressure build up in convergent film. Since the provides low power dissipation above lift-off speed and flexible an adaptivity against high temperatures, manufacturing errors or rotor growth, is particular suitable for rotating machineries. corresponding dynamic behavior depends on operational parameters, of s...

In this paper, the temperature dependence on optical absorption cross section of the core shell bimetallic nanoparticles (NPs) is investigated in quasi static approximation. Temperature dependence of the plasmon resonance is important issue because of recent applications of NPs of noble metal for heat treating of cancer and the computer chips. The effect of temperature on surface plasmon resona...

Dynamic behavior of a circular shaft with geometrical nonlinearity and constant spin, subjected to periodic axial load is investigated. The case of parametric combination resonance is studied. Extension of shaft center line is the source of nonlinearity. The shaft has gyroscopic effect and rotary inertia but shear deformation is neglected. The equations of motion are derived by extended Hamilto...

Abstract The compressible Reynolds equation (RE) is typically integrated within a fully coupled dynamical foil-air bearings (FABs)-rotor system via spatial Discretization transformation, e.g., finite difference (FD), element (FE). An alternative way of integrating the RE through Galerkin reduction (GR). motivation for using GR computational benefit coming from drastic condensation problem due t...

Increasing interest has been given to swirl brakes as a means of reducing destabilizing rotordynamic.forces due to leakage flows in new high speed rocket turbopumps. Although swirl brakes have been used successfully in practice {such as with the Space Shuttle HPOTP), no experimental tests until now have been pegormed to demonstrate their beneficial effect over a range of leakage flow rates. The...

basic physical principles of nuclear magnetic resonance imaging (n.m.r.i), a nonionizing medical imaging technique, are described. principles of nmri with other conventional imaging methods, ie, isotope scanning, ultrasonography and radiography have been compared. t1 and t2 and spin density (s.d.) factors and different image construction techniques based on their different combinations is discu...

Grid-connected permanent magnet synchronous generator (PMSG) wind farms may be susceptible to oscillation when connected weak grids. This paper explores the root causes of oscillations from two perspectives: model and frequency band. First, small signal PMSG farm grid-side system is established, disturbance comparison with PMSGA full-order electromagnetic transient in MATLAB/Simulink carried ou...