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951.
952.
A candle filter was used to determine flow rate characteristics of filtering suspensions under axial vibrations. In this work, a generalised analysis of filtration under vibrating conditions was developed. The model required the use of experimental data interpretation. The analysis gives in a simplified form the complicated functional relationship between time, cumulative flow, vibration parameters and other process variables.Such a relationship can be used in the design of vibratory filters for predicting flow rate with time. These filters are useful in particle separation processes.  相似文献   
953.
954.
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented  相似文献   
955.
The theory of energy-weighted acquisition (EWA) in nuclear medicine imaging is outlined, and a system that implements EWA is described. EWA reduces the effects of scattered radiation by allowing events of all energies to contribute to image formation, processing each energy with its own short-range spatial filter. This approach implements short-range energy-dependent filtering with an image buffer called a weighted acquisition module, providing scatter reduction with controllable noise and resolution properties. The system's response to point sources and planar distributions of radioactivity embedded in radiation-scattering media have been measured. EWA is compared to conventional energy-window acquisition, showing that the EWA approach provides improved image contrast  相似文献   
956.
957.
958.
在巴西伊加拉帕瓦水电站,通过监测电气气隙,避免了一台新水轮发电机发生重大破坏和昂贵的停机事故.  相似文献   
959.
Asymmetry, also known as domain bloom, is a systematic imperfection caused by the writing process in optical or magneto-optical recording. At the reading end of the system, asymmetry causes shifts of adjacent signal transitions in opposite directions. We present a simple nonlinear model for the replay signal in the presence of asymmetry. The model is specified by a single parameter, which is proportional to asymmetry, and its accuracy is demonstrated by application to replay signals from digital video disk drives. Based on the proposed model, a maximum-likelihood sequence detector is designed for replay signals with asymmetry. Simple modifications of the proposed detector lead to significant reductions in complexity, while the attainable performance, evaluated both analytically and through error-rate simulations, is superior to that of conventional techniques.  相似文献   
960.
Nickel molybdate catalysts used in several different upgrading reactions of coal-derived materials from low-rank Australian coals have been regenerated and their activity assessed using a number of physical and chemical techniques. Regeneration of spent coked catalysts for 20 hours in air at 450°C was sufficient to restore chemical hydrogenation activity to catalyst used for pre-asphaltene, asphaltene and oil upgrading, provided poisoning of the catalyst surface by other impurities, principally chlorine-containing molecules, had not occurred.  相似文献   
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