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31.
Modeling, Simulation, and control of switched reluctance motor drives   总被引:3,自引:0,他引:3  
This paper presents the modeling, simulation, and control aspects of four-quadrant switched reluctance motor (SRM) drives. The design of SRM drive systems must be focused on application-based appropriate control and engineering solutions needed to overcome the practical issues. A complex model is described for the physical motor simulation to incorporate the important dynamics of the SRM. A simpler, but quite accurate, model is presented for the SRM controller. Various practical limitations have been incorporated in the simulation model to make it closer to the experimental setup. The SRM control parameters are chosen based on torque-per-ampere maximization requirement. Experimental results for a 1.0-kW SRM obtained on a digital platform are presented along with useful guidelines for prototype implementation.  相似文献   
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Wireless Personal Communications - Wireless sensor networks (WSNs) are one of the very active research area. They have many applications like military, health care, environmental monitoring and...  相似文献   
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Gelatin is a highly purified animal protein of pig, cow, and fish origins and is extensively used in food, pharmaceuticals, and personal care products. However, the acceptability of gelatin products greatly depends on the animal sources of the gelatin. Porcine and bovine gelatins have attractive features but limited acceptance because of religious prohibitions and potential zoonotic threats, whereas fish gelatin is welcomed in all religions and cultures. Thus, source authentication is a must for gelatin products but it is greatly challenging due to the breakdown of both protein and DNA biomarkers in processed gelatins. Therefore, several methods have been proposed for gelatin identification, but a comprehensive and systematic document that includes all of the techniques does not exist. This up-to-date review addresses this research gap and presents, in an accessible format, the major gelatin source authentication techniques, which are primarily nucleic acid and protein based. Instead of presenting these methods in paragraph form which needs much attention in reading, the major methods are schematically depicted, and their comparative features are tabulated. Future technologies are forecasted, and challenges are outlined. Overall, this review paper has the merit to serve as a reference guide for the production and application of gelatin in academia and industry and will act as a platform for the development of improved methods for gelatin authentication.  相似文献   
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Five N balance studies were conducted to determine the faecal composition and N excretion of feeding raw Lupinus angustifolius seed meal and its fractions for growing rats using a semi-synthetic lactalbumin-based diet as control. Diets were formulated to have equal amounts of energy. The protein was incorporated at the level of 10% bulk and contained unsupplemented lupin seed meal (LMU) and fully supplemented lupin seed meal (LMFS) at 360 g kg−1 diet, aqueous extract non-dialysed (LPAND) at 196 g kg−1 aqueous extract dialysed soluble at pH 7·0 (LPAD) at 148 g kg−1 aqueous extract dialysed insoluble at pH 7·0 (LPADI) at 124 g kg−1, buffer dialysed soluble at pH 7·0 (BUSOL) at 136 g kg−1, buffer dialysed insoluble at pH 7·0 (BUDI) at 119 g kg−1 and lupin meal residue after aqueous and buffer extraction (LMR) at 170 g kg−1 diet. Rats were pair-fed for 10 days with all the above diets which had been supplemented with essential amino acids up to the target requirements for rats. Faecal wet and dry weight were increased in rats fed on LMU, LMPS and LMR diets compared to those obtained from the control diet based on lactalbumin (milk protein) LACT. The higher faecal weight was largely due to water content. The higher faecal N excretion observed in LMU, LMFS, LPAND, LPAD, BUSOL, BUDI and LMR compared to that of LACT diet was significantly lower and thus which was assumed not to be due to a decrease in the digestibility of the dietary protein, which was over 90% as compared to that in the control group. Analysis suggested that an increase in endogenous N excretion is involved in the rise of its excretion in the faeces, and indicates a long-term effect of this seed as a protein and or fibre source in monogastrics.  相似文献   
36.
Ultrastructural examination was performed in 9 biopsy specimens from 4 patients with the Cockayne-Touraine type of epidermolysis bullosa dystrophica dominans. The specimens were taken from: 1. clinically normal skin from the blister-nonpredilected sites (trunk) as well as 2. atrophic, 3. intact, and 4. experimentally frictioned skin regions from the blister-predilected sites (extremities). In the frictioned skin a dermolytic blister formations was observed. Development of anchoring fibrils showed a marked regional difference, the counts of fibrils being significantly lower (40%) in the predilection sites than in the nonpredilection sites. In addition the anchoring fibrils showed a variable degree of abnormal structure. The low frequency of often abnormally structured anchoring fibrils in the blister-preferred sites provides a good explanation for the clinical features. More studies are needed to see if regional differences in fibril frequency is a feature also of normal skin, in which case the dominant epidermolysis gene may represent a mutated structural anchoring fibril gene.  相似文献   
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As part of a multifactorial computer-assisted study of patients with asthma, the relationship between air pollution, animal dander and asthma symptoms was evaluated. No association was found between four major air pollutants (carbon monoxide, ozone, nitrogen oxides and sulfur dioxide) and asthma symptoms. Patients who owned cats and dogs reported more severe asthma symptoms (p less than .01) than patients who did not own cats and dogs. The evaluations completed to date indicate that daily exposure to cats and dogs accounts for more of the asthma symptoms differences between patients than daily exposure to air pollutants.  相似文献   
40.
1. Using the technique of density-labelling with deuterium oxide, evidence has been obtained for the de novo synthesis of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADPH+ 1-oxidoreductase, EC 1.1.1.49), during the culture of synchronously growing plant cells. 2. The entire increase in enzyme activity during the early cell cycles in this material can be accounted for by the appearance of an enzyme species with increased buoyand density. 3. A method is described for resolving overlapping distribution profiles after density centrifugation, which allows estimation of the amount of each species present at different times, and calculation of the loss of activity of the light species present from the start of culture. 4. Loss of activity of glucose-6-phosphate dehydrogenase in normal growing conditions in the presence of 2,4-dichlorophenoxyacetic acid is very much faster than in conditions which do not lead to cell division: in the absence of 2,4-dichlorophenoxyacetic acid, or in the presence of the inhibitor of RNA synthesis, 6-methylpurine.  相似文献   
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