Current Issue : January - March Volume : 2018 Issue Number : 1 Articles : 5 Articles
China Sea observed by the mmwave channel of FY3 MWRI, explains the reason\nfor which the analysis method combined with multiple mmwave channels\nis conducive to wind inversion, uses the complex model of the two-scale randomly\nrough surface with foam scattering layer to calculate the backward heat\nemission, analyzes the different response characteristics of the thermal radiation\ncharacteristics of each channel with the change of the sea surface wind\nspeed, and establishes the wind speed inversion model applying to the microwave\nradiometer, achieving better results than in previous studies. The sea\nsurface medium-low wind speed precision standard deviation of new model\nreaches 1.2 m/s (0 - 15 m/s); the inversion strong wind data are consistent\nwith the island fixed buoys data, and the global sea surface wind speed image\nschematic diagram is given....
This paper discusses a novel method of analyzing the dielectric properties of\njuices at various frequencies of microwave band. The measurements were\nperformed using a rectangular cavity with the perturbation technique at the\nS-band of microwave frequency with fresh juices made instantly from the\nfruits as well as collected from the packed fruit juices available in the market\nwith the normal added preservatives in order to keep the increase of the shelf\nlife. From the results, it is observed in the certain dielectric properties, the\nfresh juices samples and packed juices samples were varying and also varying\nover a period of time. This measurement method is simple and quick and can\nbe used over a range of juices. These results prove a new method of determining\nthe quality control of juices using microwave principles...
Due to their rapid, selective, and volumetric heating, microwaves have been widely used in\nthe past to enhance solid-state reactions as well as the synthesis of ceramic pigments. The aim of this\nwork is to present a case study involving the preparation of blue CoAl2O4 pigment using different\nmicrowave applicators and generator frequencies, showing the advantages which can derive from\na properly designed microwave reactor for the solid-state synthesis of such pigment. The results\nshow that, when using a properly designed microwave applicator, the specific energy consumption\ncan be significantly lowered compared to conventional heating techniques. Consistently with the\ndata on the dielectric properties of precursors found in literature, the microwave processing of cobalt\noxide and aluminum hydroxide mixtures resulted more favorable at 2.45 GHz than at 5.8 GHz\nmicrowave frequency....
In this study, a proposed Microwave-Induction Heating (MIH) scheme has been\nsystematically studied to acquire suitable MIH parameters including chamber pressure, microwave\npower and heating time. The proposed MIH means that the thin indium tin oxide (ITO) metal\nbelow the Poly(4-vinylphenol) (PVP) film is heated rapidly by microwave irradiation and the heated\nITO metal gate can heat the PVP gate insulator, resulting in PVP cross-linking. It is found that the\nattenuation of the microwave energy decreases with the decreasing chamber pressure. The optimal\nconditions are a power of 50 W, a heating time of 5 min, and a chamber pressure of 20 mTorr. When\nsuitable MIH parameters were used, the effect of PVP cross-linking and the device performance\nwere similar to those obtained using traditional oven heating, even though the cross-linking time\nwas significantly decreased from 1 h to 5 min. Besides the gate leakage current, the interface trap\nstate density (Nit) was also calculated to describe the interface status between the gate insulator and\nthe active layer. The lowest interface trap state density can be found in the device with the PVP\ngate insulator cross-linked by using the optimal MIH condition. Therefore, it is believed that the\nMIH scheme is a good candidate to cross-link the PVP gate insulator for organic thin-film transistor\napplications as a result of its features of rapid heating (5 min) and low-power microwave-irradiation\n(50 W)....
A quasi-optical multi-ray model for a short-range millimeter wave radar is presented.\nThe model considers multi-path effects emerging while multiple rays are scattered from the target\nand reflected to the radar receiver. Among the examined scenarios, the special case of grazing ground\nreflections is analyzed. Such a case becomes relevant when short range anti-collision radars are\nemployed in vehicles. Such radars operate at millimeter wavelengths, and are aimed at the detection\nof targets located several tens of meters from the transmitter. Reflections from the road are expected\nto play a role in the received signal strength, together with the direct line-of-sight beams illuminated\nand scattered from the target. The model is demonstrated experimentally using radar operating in\ntheW-band. Controlled measurements were done to distinguish between several scattering target\nfeatures. The experimental setup was designed to imitate vehicle near-ground millimeter wave radars\noperating in vehicles. A comparison between analytical calculations and experimental results is made\nand discussed....
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