Ultra-high field (UHF) magnetic resonance imaging (MRI) has the advantages of a higher signal-to-noise ratio (SNR) (1, 2) as well as enhanced susceptibility T2* contrast (3, 4). However, it also has drawbacks, such as the inherent inhomogeneous radiofrequency (RF) magnetic (B1) field as well as limited penetration depth. The later is often affected by wave interaction between subject and RF coi...

In this paper we investigate weak keys of universal hash functions (UHFs) from their combinatorial properties. We find that any UHF has a general class of keys, which makes the combinatorial properties totally disappear, and even compromises the security of the UHFbased schemes, such as the Wegman-Carter scheme, the UHF-then-PRF scheme, etc. By this class of keys, we actually get a general meth...

The reliability of electrical energy networks depends on both the quality and the reliability of its electrical equipment, e.g. power transformers. Local failures inside their insulation can lead to breakdowns and hence to high outage and penalty costs. Usually, power transformers are tested on partial discharge (PD) activity before commissioning. UHF PD monitoring can be used to prevent these ...

Introduction In the last 10 years the use of MR-scanners with a magnetic field stronger than 3 Tesla (“Ultra-high field MRI”, ie. UHF-MRI, defined as 7 9.4 Tesla in this presentation) has increased sharply, mainly driven by the fact that the three main manufacturers decided to develop 7Tesla MRI scanners for research purposes. More recently, also human 9.4 Tesla research MRI scanners are offere...

The radio system for very/ultra high frequency (VHF/UHF) spectrum monitoring and signal processing used in direction finding is presented this paper. This main function based on the implementation of a 6-channel VHF/UHF receiver. multicoupler unit allows selection desired band analysis verified according to user requirements. Several measured electrical characteristics receiver are just illustr...

An overview of academic and industry solutions to UHF RFID portals.