abstract— data grids are an important branch of gird computing which provide mechanisms for the management of large volumes of distributed data. energy efficiency has recently emerged as a hot topic in large distributed systems. the development of computing systems is traditionally focused on performance improvements driven by the demand of client's applications in scientific and business ...

Background: In conventional radiation therapy, regarding normal tissue tolerance, the treatment of bulk tumors is one of the remaining challenges. Grid Radiation Therapy (GRT) is a technique to deliver high doses, approximately 15 – 20 Gy per fraction, to several small volumes located in a large radiation field. This can be performed using a grid block. The current work has concentrate...

The goal of this work is the design of highly accurate surgical navigation methods purely based on magnetic resonance imaging. In this context we numerically examine the geometrical distortions which occur in magnetic resonance imaging. We extend an existing method for computing magnitude and direction of distortions for any internal point. In particular, a multi-grid approach for a fast and ef...

Confining dense plasma in a field reversed configuration (FRC) is considered a promising approach to fusion. Numerical simulation of this process requires setting artificial boundary conditions (ABCs) for the magnetic field because whereas the plasma itself occupies a bounded region (within the FRC coils), the field extends from this region all the way to infinity. If the plasma is modeled usin...

Introduction: Radiation-induced bystander effect (RIBE) is a well-known response associated with the induction of radiation effects in non-irradiated cells via signaling of hit ones. As this so-called phenomenon has been largely investigated in low dose levels, few studies focused on higher dose levels such as grid therapy. Grid therapy or spatially fractionated gri...

Results of 2D simulations of the magnetorotational mechanism of su-pernova type II are presented. Amplification of toroidal magnetic field of the star due to differential rotation of the star leads to the transformation of the rotational (gravitational) energy to the energy of the supernova explosion. In our simulation the energy of the explosion is 1.12 · 10 51 erg. The explosion ejects about ...

Vortex beams carrying orbital angular momentum have been produced recently with electron microscopy by interfering an incident electron beam with a grid containing dislocations. Here, we present an analytical derivation of vortex wave functions in reciprocal and real space. We outline their mathematical and physical properties and describe the conditions under which vortex beams can be used in ...

We describe a collaborative virtual environment system for visualization of diffusion magnetic resonance imaging scans. The system represents the 3D data by arrays of polyhedra, coloured by the degree of anisotropy and directed by the principal component of the diffusion tensor. Users can then collaboratively explore the data and interactively spawn tractography procesess that compute tracks th...

It is shown that two-dimensional MHD turbulence is in certain respects closer to threedimensional than to two-dimensional hydrodynamic turbulence. A second-order closure indicates that: (i) a t zero viscosity and magnetic diffusivity, a singularity appears a t a finite time; (ii) there is an energy cascade to small scales and an inverse cascade of squared magnetic potential, in agreement with a...

We use the grid of models described in paper I to analyse those millisecond pulsar binaries whose secondaries have been studied optically. In particular, we find cooling ages for these binary systems that range from < 1Gyr to ∼ 15Gyr. Comparison of cooling ages and characteristic spin down ages allows us to constrain the initial spin periods and spin-up histories for individual systems, showing...