In magnetic resonance electrical impedance tomography (MREIT), we measure the induced magnetic flux density inside an object subject to an externally injected current. This magnetic flux density is contaminated with noise, which ultimately limits the quality of reconstructed conductivity and current density images. By analysing and experimentally verifying the amount of noise in images gathered...

Alkali-metal magnetometers compete with SQUID detectors as the most sensitive magnetic field sensors. Their sensitivity is limited by relaxation due to spin-exchange collisions. We demonstrate a K magnetometer in which spin-exchange relaxation is completely eliminated by operating at high K density and low magnetic field. Direct measurements of the signal-to-noise ratio give a magnetometer sens...

conclusion vr reconstruction for both single-direction images and sushi using dti25 raw data provides excellent 3d displays of the peripheral nerves in the wrist region. sushi post-processing is a useful denoising tool because it automatically reduces the majority of isotropic object noise. results single-direction vr reconstruction clearly showed the nerves for both dti6 and dti25 but with obv...

This study introduced a method based on magnetic field assisted finishing mechanism for micromachining the inner surfaces of Aluminum tubes. In this approach, using the alternating magnetic field of an AC electromotor, abrasive particles were formed as Magnetic Rods (Magnetic Clusters) and surface micromachining was carried out by the dynamic particular pattern made by an alternating magnetic f...

This study deals with the 3D recovering of magnetic susceptibility model by incorporating the sparsity-based constraints in the inversion algorithm. For this purpose, the area under prospect was divided into a large number of rectangular prisms in a mesh with unknown susceptibilities. Tikhonov cost functions with two sparsity functions were used to recover the smooth parts as well as the sharp ...

The contribution gives results of the theoretical analysis of the noise properties of the RF magnetic field receivers using the Superconducting Quantum Magnetometer (SQM) for NMR systems with the low magnetic field (Low-Field-NMR). The relation for the equivalent spectral sensitivity of the magnetic induction of the receiver, which covers the influence of the intrinsic noise of SQM, antenna sys...

High-permeability magnetic shields generate magnetic field noise that can limit the sensitivity of modern precision measurements. We show that calculations based on the fluctuation-dissipation theorem allow quantitative evaluation of magnetic field noise, either from current or magnetization fluctuations, inside enclosures made of high-permeability materials. Explicit analytical formulas for th...

a new method derived by salem et al. (2004) for interpretation of gravity and magnetic anomalies is used to determine the depth and shape factor of the gravity anomalies. the depth and shape factor of some rectangular prisms as synthetic models are estimated using the method. the gravity effects of the models are contaminated with some random noise and then the parameters of the models are extr...

A new important advantage has been discovered for the fundamental-mode operation of the orthogonal fluxgate employing an amorphous wire. It has been found that a great enough dc bias practically completely suppresses the magnetic noise generated in the fluxgate core by the ac-bias field; the fluxgate resolution becomes limited only by the excess electric noise in the ac-bias current. As a resul...