We present microwave ~30 GHz! measurements on aluminum superconducting hot-electron bolometer ~HEB! mixers. Aluminum HEB mixers have a lower superconducting transition temperature than niobium and niobium nitride devices, and are predicted to have improved sensitivity and require less local oscillator power. The devices studied consist of a narrow superconducting aluminum microbridge with conta...

Spectrum sensing is used in Cognitive Radio (CR) to be able to detect which frequency can be used for communication. Spectrum sensing is done with Spectrum Analyzers (SAs). An existing one-antenna cross-correlation SA (XCSA) uses cross-correlation to achieve a very low noise figure (NF) to be able to sense the spectrum more accurately. Uncorrelated noise added in two signal paths is averaged ou...

Several state-of-the-art wireless receiver architectures are presented including the traditional superheterodyne, the image-reject heterodyne, the direct-conversion, and the very-low intermediate frequency (VLIF). The case studies are followed by a detailed view of receiver building blocks: lownoise amplifiers (LNA), mixers, and voltage-controlled oscillators (VCO). Two popular topologies curre...

The diurnal variation in peak expiratory flow rate (PEFR) was studied in 26 mixers from eight factories making polyurethane foam, who were exposed to toluene diisocyanate (TDI), and 26 unexposed controls matched for age, race, and smoking. They were all men. The mean diurnal variation in PEFR of the mixers was 6.2%, which was significantly higher than the 4.3% for controls. Six mixers had a diu...

Asymmetric and symmetric chaotic attractors produced by the simplest jerk equivariant system are topologically characterized. In the case of this system with an inversion symmetry, it is shown that symmetric attractors bounded by genus-one tori are conveniently analyzed using a two-components Poincaré section. Resulting from a merging attractor crisis, these attractors can be easily described a...

Top-down surface mixers are increasingly used in drinking water reservoirs to prevent the development of stratification, control cyanobacteria, and limit sediment release soluble manganese. A targeted field investigation enabled discrimination artificial mixing by from wind convection a shallow (6.6 m), eutrophic reservoir. were effective at reducing vertical temperature dissolved oxygen gradie...

Resistive switching (RS) and Resistive Random Access Memories (ReRAMs) that exploit it have attracted huge interests for next generation non volatile memory (NVM) applications, also thought to be able to overcome flash memories limitations when arranged in crossbar arrays. A cornerstone of their potential success is that the RS between two different resistive states, usually High (HRS, High res...

A novel extension to a previous method has been proposed to evaluate the nature of dry powder mixing processes using a mixing sensitive colouring agent. The method proposed measures the change in the colour (hue) and colour intensity of the powder blends over mixing time. To evaluate the extent of fine particle dispersion and de-agglomeration, cohesive and free flowing lactose (white) and cohes...