We have designed and constructed a Fourier Transform Spectrometer (FTS) for the study of submillimeter-wave mixers and optical components. The FTS has a large aperture (up to 25.4 cm) and small focal ratio (as fast as f/2.5) to achieve a large throughput. It operates in the 100-3750 GHz (3.3125 cm 1) frequency range with a resolution of up to 75 MHz (0.0025 cm ). Here we discuss the design goal...

OBJECTIVES To determine the occurrence of hypothermia in patients with minor trauma, to test the hypotheses that resistive heating during transport is effective treatment for hypothermia and that this treatment reduces patients' thermal discomfort, pain, and fear, and to evaluate the accuracy of oral temperatures obtained at the scene of injury. PATIENTS AND METHODS In December 1999 and Janua...

Dry dispersible substances are used as raw materials in almost all branches of production, mainly chemical, pharmaceutical, food, construction and other industries. Therefore, there is always a need for facilities that process this product. One the most important these devices mixer. First all, it an task to create efficient energy-efficient mixers suitable product type production process. Mixe...

The aim of microfluidic mixing is to achieve a thorough and rapid mixing of multiple samples in microscale devices. In such devices, sample mixing is essentially achieved by enhancing the diffusion effect between the different species flows. Broadly speaking, microfluidic mixing schemes can be categorized as either "active", where an external energy force is applied to perturb the sample specie...

In this paper we present the development of low-noise waveguide mixers with NbN/AlN/NbN tunnel junctions at frequency approaching 1THz. The mixer was designed to be compatible with MgO substrate. Mixers of such a design demonstrated much improved receiver sensitivity. The improvement is a result of reduction of signal dissipation in waveguide and leakage into IF port by adopting a full-height w...

This paper reports on a study concerned with the numerical simulation of dough mixing that arises in the food processing industry. The flows considered are in a complex domain setting. Two dough mixers at various rotation speeds are studied; one with one stirrer and the other with two stirrers. Numerical simulations are based on three dimensions in the cylindrical polar co-ordinates system. The...

This paper describes calibration techniques for downconversion mixers used in integrated direct-conversion receivers. A method of achieving a high even-order intermodulation rejection is presented. Using the method presented, the receiver second-order input intercept point (IIP2) can always be improved by more than 20 dB. The minimum achieved receiver IIP2 after calibration is +38 dBm. A techni...

BACKGROUND AND OBJECTIVES We investigated the mixing capacity of two whole blood (WB) collection mixers. MATERIALS AND METHODS WB was simulated by using a 25% glycerol solution warmed to 35 degrees C. Citrate-phosphate-dextrose (CPD) anticoagulant of a collection system was stained with toluidine blue, and simulated WB was added at 30, 60 or 90 ml/min, respectively (n = 3 per flow speed). The...

A wireless sensor server is developed based on a reconfigurable active smart-antenna/retrodirective array. The system can serve as both a retrodirective array transponder and a smart-antenna receiver simply by changing the frequency of the local oscillator applied to the mixers, enabling it to best utilize its hardware to suit its communication environment. When operating as a direct-conversion...

Two arrow-shaped micro-mixers, obtained from the classical T-shaped geometry by tilting downward inlet channels, are considered herein. The two configurations, having different angle values, have been chosen since they show significantly flow topologies and mixing performances at low Reynolds numbers. In present paper, we use both experimental visualizations direct numerical simulations to shed...