Results 211 to 220 of about 9,732,619 (263)
Some of the next articles are maybe not open access.
Current Density Impedance Imaging
IEEE Transactions on Medical Imaging, 2008Current density impedance imaging (CDII) is a new impedance imaging technique that can noninvasively measure the conductivity distribution inside a medium. It utilizes current density vector measurements which can be made using a magnetic resonance imager (MRI) (Scott , 1991). CDII is based on a simple mathematical expression for inverted Delta sigma /
Karshi F. Hasanov +3 more
openaire +2 more sources
Low-Density Parity-Check Codes and Their Rateless Relatives
IEEE Communications Surveys and Tutorials, 2011 This survey guides the reader through the extensive open literature that is covering the family of low-density parity-check LDPC codes and their rateless relatives.
Sheng Chen +2 more
exaly +3 more sources
Science, 1966
Diurnal solar heating produces an unstable warm zone just off the bottom of the inshore regions of a salt lake. The warm water rises in plumes in which brine shrimp become entrapped through apparently negative photokinetic behavior. The plumes of concentrated shrimp resemble those composed of insects in air.
openaire +2 more sources
Diurnal solar heating produces an unstable warm zone just off the bottom of the inshore regions of a salt lake. The warm water rises in plumes in which brine shrimp become entrapped through apparently negative photokinetic behavior. The plumes of concentrated shrimp resemble those composed of insects in air.
openaire +2 more sources
Current density partitioning in time-dependent current density functional theory
The Journal of Chemical Physics, 2014We adapt time-dependent current density functional theory to allow for a fragment-based solution of the many-electron problem of molecules in the presence of time-dependent electric and magnetic fields. Regarding a molecule as a set of non-interacting subsystems that individually evolve under the influence of an auxiliary external electromagnetic ...
MartÃn A, Mosquera, Adam, Wasserman
openaire +2 more sources
The Journal of Chemical Physics, 2018
It is shown that nonsymmetric second-rank current density tensors, related to the current densities induced by magnetic fields and nuclear magnetic dipole moments, are fundamental properties of a molecule. Together with magnetizability, nuclear magnetic shielding, and nuclear spin-spin coupling, they completely characterize its response to magnetic ...
openaire +2 more sources
It is shown that nonsymmetric second-rank current density tensors, related to the current densities induced by magnetic fields and nuclear magnetic dipole moments, are fundamental properties of a molecule. Together with magnetizability, nuclear magnetic shielding, and nuclear spin-spin coupling, they completely characterize its response to magnetic ...
openaire +2 more sources
Current density and temperature of high-current arcs
Electrical Engineering, 1957DURING INTERRUPTION of high-current arcs in circuit breakers and contactors, the region between the contacts must be converted from an intensely hot conducting medium to a relatively cool insulating medium. Although the cooling of low-current arcs has been explained by means of conduction, free convection, and radiation, extension of these mechanisms ...
T. H. Lee, W. R. Wilson, J. C. Sofianek
openaire +1 more source
The current density in quantum electrodynamics
Il Nuovo Cimento, 1952The formulation of field theory given previously suggests an alternative expression for the current density in quantum electrodynamics. This expression is gauge-invariant and conserved and differs from the usual current density by the divergence of a tensor which vanishes in the absence of a field. Corresponding to this current is a new electromagnetic
openaire +2 more sources
Maps of current density using density-functional methods
The Journal of Chemical Physics, 2008The performance of several density-functional theory (DFT) methods for the calculation of current densities induced by a uniform magnetic field is examined. Calculations are performed using the BLYP and KT3 generalized-gradient approximations, together with the B3LYP hybrid functional. For the latter, both conventional and optimized effective potential
Soncini A. +4 more
openaire +3 more sources
Journal of Membrane Science, 2002
Abstract The current density distribution in a seawater electrodialyzer is approximated by a quadratic equation. The equation is solved using a three-dimensional simultaneous equation, and the current density distribution and the coefficients expressing the current density distribution are calculated.
openaire +1 more source
Abstract The current density distribution in a seawater electrodialyzer is approximated by a quadratic equation. The equation is solved using a three-dimensional simultaneous equation, and the current density distribution and the coefficients expressing the current density distribution are calculated.
openaire +1 more source
Current density in a perfect mirror
Optics Letters, 2008Electromagnetic radiation incident upon a perfect mirror induces a current density on the surface of the conducting material of the mirror. It is shown that this surface current density can be expressed directly in terms of the source current density, which generates the incident field, without evaluating the electric and magnetic fields first.
openaire +2 more sources