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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
972.
Tresadern P.A. Thies S.B. Kenney L.P.J. Howard D. Goulermas J.Y. 《Pervasive Computing, IEEE》2008,7(2):62-69
The clinical set-up tool integrates fast parameter selection and a user-friendly interface to help electrical muscle stimulators more efficiently treat patients with neurological injuries. A key challenge in increasing functional electrical stimulation systems' clinical acceptance is facilitating or automating parameter selection, optimization, and programming to make the underlying engineering transparent to the user. To this end, we present the clinical set-up tool (CST), a finite-state-machine-based controller that integrates accurate, automatic parameter optimization in an intuitive user interface. Unlike other approaches, we employ a numerical algorithm that uses real-life data and well-defined criteria to rapidly optimize parameter values. 相似文献
973.
Hodgins D. Bertsch A. Post N. Frischholz M. Volckaerts B. Spensley J. Wasikiewicz J.M. Higgins H. von Stetten F. Kenney L. 《Pervasive Computing, IEEE》2008,7(1):14-21
Healthy Aims is a 23- million, four-year project, funded under the EU's information society technology sixth framework program to develop intelligent medical implants and diagnostic systems (www.healthyaims.org). The project has 25 partners from 10 countries, including commercial, clinical, and research groups. This consortium represents a combination of disciplines to design and fabricate new medical devices and components as well as to test them in laboratories and subsequent clinical trials. The project focuses on medical implants for nerve stimulation and diagnostic equipment based on strain-gauge technology. 相似文献
974.
975.
Haratcherev L. Taal J. Langendoen K. Lagendijk R. Sips H. 《Communications Magazine, IEEE》2006,44(1):115-121
Seamless video streaming over wireless links imposes strong demands on video codecs and the underlying network. It is not sufficient that only the video codec or only the radio adapts to changes in the wireless link quality; efforts should be applied in both layers, and - if possible - synchronized. Also, the disturbing effect of possible background traffic over the same shared medium has to be taken into account. In this article we present a communication architecture for video streaming over 802.11 that is capable of adapting to changes in the link quality and sharing of the wireless channel in various use scenarios. Experimental results show that substantial improvements in the quality of the video can be obtained by applying link adaptation and cross-layer signaling techniques. 相似文献
976.
A. L. Lapidus V. S. Budtsov A. P. Savost’yanov N. V. Vysochin 《Solid Fuel Chemistry》2008,42(5):306-307
The adequacy of a model developed for the synthesis of hydrocarbons from CO and H2 was assessed. It was found that the results calculated based on this model correspond to experimentally obtained data with a high degree of accuracy (the squared coefficient of correlation was higher than 0.97). 相似文献
977.
Synthesis and characterization of acidic properties of Al-SBA-15 materials with varying Si/Al ratios
G. Muthu Kumaran Shelu Garg Kapil Soni Manoj Kumar J.K. Gupta L.D. Sharma K.S. Rama Rao G. Murali Dhar 《Microporous and mesoporous materials》2008,114(1-3):103-109
Al-SBA-15 of varying Si/Al ratios in the range 11.4–78.4 was synthesized using tri-block copolymer P123. The calcined materials were examined by XRD, pore size distribution, surface area, 27Al NMR spectroscopy. The acidity and acid strength distribution were studied using microcalorimetric adsorption of NH3. The acidic properties were also examined by cumene cracking reaction as a function of Si/Al ratios. Systematic variation of acidity and activity was observed as a function of Si/Al ratio. The initial heats of NH3 adsorption correlated well with activity indicate that acid sites with ΔH > 100 kJ/mole is responsible for cumene cracking activity. Linear correlations were obtained with total acidity and cumene cracking activities. The tetrahedral aluminum was found to be responsible for the observed acidities and catalytic activities. 相似文献
978.
L. B. Pavlovich N. N. Nazarov V. P. Dolgopolov A. V. Kalinina T. A. Bulis D. V. Bal’tser V. P. Konstantinov 《Coke and Chemistry》2008,51(7):277-282
The use of biochemically purified water in place of industrial-grade water for the exhaust-gas scrubbers in the drying department of the coal-enrichment shop and for irrigation of the cyclone washers in the coke shops at OAO ZSMK is considered. It is found that biochemically purified water may be used for 100% of the water needs in coke production. Using biochemically purified water in the dust-trapping equipment, the coaland coke-dust content of the atmospheric emissions may be reduced by 24.5%. Additional purification of wastewater by adsorption on coke and coal dust is possible. 相似文献
979.
R. T. Jarviste R. T. Muoni J. H. Soone H. J. Riisalu A. L. Zaidentsal’ 《Solid Fuel Chemistry》2008,42(2):123-127
Diesel fuel should satisfy the European standards of quality even after long-term storage. The oxidation of diesel fuel, factors affecting this process, and their interaction mechanisms were studied in this work. Based on the results, conditions for the long-term storage of diesel fuel, including the type of storage tanks, can be determined. 相似文献
980.
L. V. Ravichev A. V. Bespalov V. Ya. Loginov 《Theoretical Foundations of Chemical Engineering》2008,42(3):314-323
A mathematical model for calculating the viscous properties of concentrated suspensions characterized by particle sizes of 30 to 800 µm), solids volume fractions of 1 to 70 vol %, different particle-size distributions, and a shear-rate range of 0.16 to 437 s?1, which can describe the time evolution of the properties, is proposed. The model can be applied to calculating the viscous properties of catalyst oxide pastes, particulate-filled polymeric pastes, and the like. 相似文献