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991.
Ioanna Roussaki Maria Strimpakou Carsten Pils 《Journal of Network and Systems Management》2007,15(1):57-74
The challenge of saturating all phases of pervasive service provision with context-aware functionality lies in coping with
the complexity of maintaining, retrieving and distributing context information. To efficiently represent and query context
information a sophisticated modelling scheme should exist. To distribute and synchronise context knowledge in various context
repositories across a multitude of administrative domains, streamlined mechanisms are needed. This paper elaborates on an
innovative context management framework that has been designed to cope with free-text and location based context retrieval
and efficient context consistency control. The proposed framework has been incorporated in a multi-functional pervasive services
platform, while most of the mechanisms it employs have been empirically evaluated. 相似文献
992.
分别以94%品位高钛渣和90%品位高钛渣为原料,采用沸腾氯化工艺制备粗TiCl4,分析了两种品位高钛渣对沸腾氯化工艺的影响。结果表明:94%品位高钛渣由于其活性低而对沸腾氯化工艺的影响较大。 相似文献
993.
994.
The Ordered Bed Modular Reactor (OBMR) is an advanced modular HTGR design in which the annular reactor core is filled with an ordered bed of fuel spheres. This arrangement allows fuel elements to be poured into the core cavity which is shaped so that an ordered bed is formed and to be discharged from the core through the opening holes in the reactor top. These operations can be performed in a shorter shutdown time. 相似文献
995.
996.
The electrochemical properties of an electrochemical double-layer capacitor electrode based on an ultra-long (500 μm), aligned, carbon nanotube array (ACNTA) in Et4NPF6/propylene carbonate electrolyte are examined. The specific capacitance of the ACNTA electrode in an organic electrolyte is 24.5 F g−1, which is larger than that obtained in an aqueous electrolyte. The results of ac impedance measurements show that the ACNTA electrode gives a high power density and an excellent rate capability in an organic electrolyte. It is shown that the ACNTA electrode has a lower equivalent series resistance and a better rate capability than activated carbon electrode. This is due to the fact that ACNTA possesses a larger pore size and a more a regular pore structure. Both these features are conformed by scanning electron microscopic and nitrogen gas adsorption studies. 相似文献
997.
Participating media with an inhomogeneous index of refraction make light follow curved paths. Simulating this in a global
illumination environment has usually been neglected due to the complexity of the calculations involved, sacrificing accurate
physical simulations for efficient visual results.
This paper aims to simulate non-linear media in a more reasonable time than previous works without losing physical correctness.
Accuracy is achieved by solving the Eikonal equation of geometrical optics, which describes the path followed by a light beam
that traverses a non-linear medium. This equation is used in the context of a photon mapping extension. 相似文献
998.
The authors of this paper investigated the influence of esters of rapeseed oil fatty acids on the lubricating properties of
mineral lubricants containing chosen AW/EP additives. Methyl esters, ethylene glycol esters, and glycerol esters as well as
some commercial AW/EP packages based on zinc dialkyldithiophosphate, S–P organic compounds, and sulphurized esters of fatty
acids were tested. The tribological tests were carried out with the use of a four-ball machine. Antiwear (AW) properties of
tested compositions were determined using their limiting load of wear (Goz(40)). It appears that the AW action of esters of rapeseed oil fatty acids depends on their structure. The best AW action is shown
by compositions of mineral oil lubricants containing AW/EP additives and methyl esters of rapeseed oil fatty acids. The SEM/EDS
analysis of the scar surface layer indicated that the presence of these esters in lubricants causes a change in the interaction
between AW/EP additives and the metal surface. These observations were confirmed by the XPS surface analysis. 相似文献
999.
Drawing Power Law Graphs Using a Local/Global Decomposition 总被引:1,自引:0,他引:1
1000.
Jeffrey E. Marchese Matteo Cirillo Niels Grøch-Jensen 《Open Systems & Information Dynamics》2007,14(2):189-196
We present evidence for a close analogy between the nonlinear behaviour of a pulsed microwave-driven Josephson junction at
low temperature and the experimentally observed behaviour of Josephson systems operated below the quantum transition temperature
under similar conditions. We specifically address observations of Ramsey-type fringe oscillations, which can be understood
in classical nonlinear dynamics as results of slow transient oscillations in a pulsed microwave environment. Simulations are
conducted to mimic experimental measurements by recording the statistics of microwave-induced escape events from the anharmonic
potential well of a zero-voltage state. Observations consistent with experimentally obtained Ramsey-type oscillations are
found in the classical model.
An erratum to this article can be found at 相似文献