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991.
Vibro-fluidized beds are widely used in drying sticky powders and agglomerated materials as milk powder. Using a vibro-fluidized laboratory scale dryer, this work is aiming at analyzing preliminarily the effect of its operational variables on the drying kinetics and characteristics of whole milk powder. The full-factorial design technique with three replications at the central point has been employed to generate data and correlations to quantify the effect of inlet air temperature, air flow rate, and vibration bed amplitude on the drying curves and the milk powder properties related to its faster reconstitution in water (as tapped density, Hausner cohesion ratio, agglomerate size distribution, and internal pore concentration). Results obtained are analyzed and discussed to identify the adequate operation condition for final drying whole milk powder in vibro-fluidized beds, assuring a high product quality. 相似文献
992.
Hongxuan Zhang Venkatesha S. Minahan R. Sherman D. Oweis Y. Natarajan A. Thakor N.V. 《IEEE engineering in medicine and biology magazine》2006,25(4):39-45
Intraoperative neurological monitoring (INM) is the evaluation of the nervous system within the operating room (OR) environment. In this paper, the INM system is tested in a clinical setting in comparison with conventional somatosensory evoked potential (SEP) monitoring. The study results demonstrate the capability of the INM system in extracting clearer and more stable SEP signals. The high SNR of SEP signals collected in various clinical environments, including the OR, makes the INM system a robust platform for continuous monitoring. While the current use of EP monitoring is limited to intermittent analysis by a highly trained clinical neurophysiologist, the authors believe in changing this paradigm by developing continuous monitoring systems, such as the INM system, capable of automated quantitative EP analysis. This noninvasive monitoring modality will allow for a wider range of use in clinical practice. Based on volunteer and clinical patient studies, the INM monitoring system demonstrates much greater reliability and accuracy via the artifact rejection and denoising strategies. It provides more strategic filtering options for different situations under which the clinical SEP response signal could be greatly contaminated and distorted. Furthermore, the INM system offers a promising approach to signal extraction in real-time monitoring during SEP research. 相似文献
993.
L A Geddes 《IEEE engineering in medicine and biology magazine》2006,25(6):92-93
This paper discusses the experiments conducted by physicist and physician Arsenne d'Arsonval on the effect of sinusoidal ac on the body, well before the era of electronics. d'Arsonval's first experiments were on the effect of ac on muscle contraction using frog muscle. He contrived a most ingenious device, which displayed the voltage curve and the force of muscle contraction on a smoked-drum kymograph. By using this instrument, along with various alternators such as the Gramme machine, d'Arsonval was able to show that the muscular contraction force decreased with increasing frequency of the electric current. d'Arsonval then turned his attention to the effect of high-frequency ac on the human body. To this end, he created a spark-gap generator of the type described by Hertz in 1888. d'Arsonval demonstrated two important facts: 1) muscle contraction force decreased with increasing frequency of the current and 2) substantial current could be passed through the body and it produced a sensation of warmth. This he proved with conductive and capacitive coupling. By his experiments, d'Arsonval laid the foundation for two new medical techniques: 1) electrosurgery and 2) diathermy. Today both fields are well established in medicine 相似文献
994.
995.
A. Bogris D. Syvridis 《Photonics Technology Letters, IEEE》2006,18(20):2144-2146
All-optical regeneration of differential phase-shift keying signals by means of a phase-sensitive amplification scheme solely based on highly efficient four-wave mixing in fibers is theoretically and numerically studied. The analytical and numerical investigation demonstrates almost ideal phase regeneration accompanied with enhanced amplitude noise suppression in the regime of pump depletion. 相似文献
996.
In this study, four similar bench-scale submerged Anoxic/Oxic Membrane Bioreactors (MBR) were used simultaneously to investigate the effects of solids retention time (SRT) on organic and nitrogen removal in MBR for treating domestic wastewater. COD removal efficiencies in all reactors were consistently above 94% under steady state conditions. Complete conversion of NH(4+)-N to NO(3-)-N was readily achieved over a feed NH(4+)-N concentration range of 30 to 50 mg/L. It was also observed that SRT did not significantly affect the nitrification in the MBR systems investigated. The average denitrification efficiencies for the 3, 5, 10 and 20 days SRT operations were 43.9, 32.6, 47.5 and 66.5%, respectively. In general, the average effluent nitrogen concentrations, which were mainly nitrate, were about 22.2, 27.6, 21.7 and 13.9 mg/L for the 3, 5, 10 and 20 days SRT systems, respectively. The rate of membrane fouling at 3 days SRT operation was more rapid than that observed at 5 days SRT. No fouling was noted in the 10 days and 20 days SRT systems during the entire period of study. 相似文献
997.
L. A. Bassalygo S. M. Dodunekov V. A. Zinoviev T. Helleseth 《Problems of Information Transmission》2006,42(3):197-203
The Grey-Rankin bound for nonbinary codes is obtained. Examples of codes meeting this bound are given.
Original Russian Text Ş L.A. Bassalygo, S.M. Dodunekov, V.A. Zinoviev, T. Helleseth, 2006, published in Problemy Peredachi
Informatsii, 2006, Vol. 42, No. 3, pp. 37–44.
Supported in part by the Russian Foundation for Basic Research, project no. 06-01-00226. 相似文献
998.
I. M. Kosareva M. K. Savushkina S. A. Kabakchi S. V. Korotkevich V. M. Kudryavtsev 《Atomic Energy》2006,100(2):83-89
The concepts of specific and absolute toxicity permit distinguishing in radioactive wastes belonging to different categories
the particular components that present the greatest ecological danger at different stages of their disposal in repositories.
It is shown that transuranium elements determine the toxicity parameter of high-and medium-level wastes only 350–400 years
after initial disposal. At the present stage of operation of deep repositories, the behavior of the long-lived fission products
of 90Sr and 137Cs is most important. For low-level wastes, the chemical and not the radioactive component is most dangerous.
__________
Translated from Atomnaya énergiya,Vol. 100, No. 2, pp. 86–92, February, 2006. 相似文献
999.
1000.
A methodology remediating zones of local radioactive contamination is presented. It is based on a classification of the zones
taking account of the contribution of external and internal irradiation to the total dose load to the public. The criteria
for identifying such loads and the steps required for their remediation are identified. A radiation-ecological validation
of the decrease in the external irradiation dose to the public in zones of local radioactive contamination is given.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 2, pp. 125–134, February, 2006. 相似文献