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...

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...

Abstruct-The two-diode subfmrmordcallypumped stripline mixer hasa pair of diodesshunt mounted with oppositepolarities in a striplfne circuit betweenthe sigsudand local oscillator inputs. The circuit haslow noiseand conversion10ssand substantialAM local oscillator noise cancellation.The load oscfflator frequency is abmsthaff the signal frequency.A novel diode chip, the notch-front dfodq which ha...

Submillimeter spectroscopy is a unique and very rich source of astrophysical information. While many important results have been obtained using ground based telescopes, the Kuiper Airborne Observatory, ISO, and SWAS, this field will soon experience rapid growth and development due to projects such as SOFIA, ALMA, and the Herschel Space Observatory (HSO). High spectral resolution is and will con...

We describe a steganographic protocol for packet switched networks that is based on the dynamic rewriting of packet headers. The protocol provides confidentiality without encryption based on Rivest’s “chaffing and winnowing” technique. We identify new places in computer networks where this method can be applied and describe an alternate chaffing method that relies on unpredictable number sequen...