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91.
Data mining is under attack from privacy advocates because of a misunderstanding about what it actually is and a valid concern about how it is generally done. This article shows how technology from the security community can change data mining for the better, providing all its benefits while still maintaining privacy. 相似文献
92.
In this study, experimental investigations on stitched and unstitched woven carbon/epoxy laminates under high strain rate compression loading are discussed. Stitched/unstitched laminates are fabricated with aerospace grade plain and satin weave fabrics with room temperature curing SC-15 epoxy resin using affordable vacuum assisted resin infusion molding process. The samples are subjected to high strain rate loading using modified compression split Hopkinson’s pressure bar at three different strain rates ranging from 320 to 1149 s−1. Results are discussed in terms of unstitched/stitched configuration, fabric type and loading directions. Dynamic compression properties are compared with those of static loading. Failure mechanisms are characterized through optical and scanning microscopy. 相似文献
93.
94.
Computational Markets to Regulate Mobile-Agent Systems 总被引:9,自引:0,他引:9
Bredin Jonathan Kotz David Rus Daniela Maheswaran Rajiv T. Imer Cagri Basar Tamer 《Autonomous Agents and Multi-Agent Systems》2003,6(3):235-263
Mobile-agent systems allow applications to distribute their resource consumption across the network. By prioritizing applications and publishing the cost of actions, it is possible for applications to achieve faster performance than in an environment where resources are evenly shared. We enforce the costs of actions through markets, where user applications bid for computation from host machines.We represent applications as collections of mobile agents and introduce a distributed mechanism for allocating general computational priority to mobile agents. We derive a bidding strategy for an agent that plans expenditures given a budget, and a series of tasks to complete. We also show that a unique Nash equilibrium exists between the agents under our allocation policy. We present simulation results to show that the use of our resource-allocation mechanism and expenditure-planning algorithm results in shorter mean job completion times compared to traditional mobile-agent resource allocation. We also observe that our resource-allocation policy adapts favorably to allocate overloaded resources to higher priority agents, and that agents are able to effectively plan expenditures, even when faced with network delay and job-size estimation error. 相似文献
95.
Metallic-glass ribbon reinforced glass-ceramic matrix composites were fabricated by conventional wet pressing and sintering techniques. Some of the important aspects of composite fabrication are discussed. Variables such as binder content, compaction pressure and specimen size, and their interdependency on one another are discussed. The optimum processing conditions required to obtain the best specimens are described. The sintering temperature was also found to be very important. The sintering temperature not only controls the softening characteristics of the parent glass, but also affects the specimen distortion. Proper selection of the sintering temperature can ensure minimum distortion in the specimens, while at the same time retain the ease and efficiency of fabrication. 相似文献
96.
Interface- and diffusion-limited capillary rise of reactive melts with a transient contact angle 总被引:1,自引:0,他引:1
Rajiv Asthana 《Metallurgical and Materials Transactions A》2002,33(7):2119-2128
The kinetics of unidirectional capillary penetration by a reactive fluid under the limiting cases of diffusion control and
interface control has been derived for the reactive infiltration phenomenon characterized by a shrinking capillary radius
due to interphase formation and an exponentially decaying contact angle. The computational outcomes for the reactive penetration
of Si3N4 capillaries by AgCuTi brazes and of carbon capillaries by Si show that greater lengths are attained at lower values of the
parabolic rate constant (under diffusion control), and the limiting length is reached earlier at larger values of the linear
rate constant (under interface control). A capillary-driven flow analysis (Washburn equation) overestimates the infiltration
kinetics, whereas an analysis that considers pore shrinkage but assumes the contact angle and the capillary pressure to be
constant during flow underestimates the kinetics. The penetration lengths predicted by the analysis at pore closure due to
reaction choking exhibit a slightly better agreement with the recent measurements in the Si/C system than the models of reactive
flows currently in vogue. 相似文献
97.
Srinivasan Palaniappan Chandrasekaran Saravanan Chellachamy Anbalagan Amarnath Vaidya Jayathirtha Rao 《Catalysis Letters》2004,97(1-2):77-81
Polyaniline salts are prepared by doping of polyaniline base with different Bronsted acids (H2SO4, HNO3 and H3PO4), organic acid — p-toluene sulfonic acid (PTSA) and Iodine (I2). Polyaniline complexes are also prepared using Lewis acids (BF3, AlCl3 and SnCl2). Polyaniline salts and polyaniline complexes are characterized by physical, electrical and spectral methods. Polyaniline salts and polyaniline complexes are used as catalyst for the first time in bisindole synthesis. Bisindole (3,3′-bis(indolyl)phenylmethane) is obtained in excellent yields with simple and more environmental benign procedure. The use of polyaniline catalysts are feasible because of their easy preparation, easy handling, stability, easy recovery, reusability, good activity and eco-friendly. 相似文献
98.
One way of overcoming the problem of false alarms encountered in a single parameter detection system due to non-fire stimulii is the simultaneous use of multiple signatures. Researchers have found significant benefits of multi-sensor detection in reducing false triggering. Appreciable interest has been expressed in using carbon monoxide (CO) or carbon dioxide (CO2) gas sensors in combination with smoke sensors. The present study has been carried out to determine the correlation and inter-dependence between two different fire signatures like CO–OD (optical density), CO–CO2, CO2–OD. The signatures have been investigated using experimental measurements of a fire inside a closed compartment measuring 7 x 7 x 4.2 m. A range of fuels are used, and both smouldering and flaming combustion are examined. Attempts have been made to examine whether correlation coefficients between two signatures can form a basis of detection and be exploited as one of the components in multi- criteria fire detection algorithm. The CO/CO2 ratio as a criterion for detector operation has also been examined and discussed in the light of existing literature and codal provisions. 相似文献
99.
Rajiv Manohar A. K. Srivastava Pankaj K. Tripathi Dharmendra P. Singh 《Journal of Materials Science》2011,46(18):5969-5976
Addition of Nano rods results change in the dielectric and electro-optical properties of pure Ferroelectric Liquid Crystal
(FLC) considerably. The present study is devoted to characterize the dielectric and electro-optical parameters of the FLC
nano rods composite system. The size of nano rods is usually much bigger than that of FLC molecules, therefore, when they
are doped in different concentrations, in pure FLC, their volume fraction plays considerable role in deciding the molecular
dynamics of the resultant composite system. For the lesser concentrations, the nano rods offer mechanical strength to system
geometry while at higher concentration of nano rods, they offer additional constraints on the system. In present report both
of these aspects have been analyzed and explained. 相似文献
100.
Variations in semen analyses of 177 males over a 1 year period were assessed. The average means of total counts, motility, morphology, total motile count and non-motile % were determined for 5 classes of patients ranging from azoospermic to normospermic. Positive relationships between a falling sperm count, a decrease in motility and total motile counts were seen. Also, increasingly, abnormal forms were found with lower sperm counts. 相似文献