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1.
Yunlei Li Dick de Ridder Robert P.W. Duin Marcel J.T. Reinders 《Pattern recognition》2008,41(1):320-330
Samples can be measured with different precisions and reliabilities in different experiments, or even within the same experiment. These varying levels of measurement noise may deteriorate the performance of a pattern recognition system, if not treated with care. Here we seek to investigate the benefit of incorporating prior knowledge about measurement noise into system construction. We propose a kernel density classifier which integrates such prior knowledge. Instead of using an identical kernel for each sample, we transform the prior knowledge into a distinct kernel for each sample. The integration procedure is straightforward and easy to interpret. In addition, we show how to estimate the diverse measurement noise levels in a real world dataset. Compared to the basic methods, the new kernel density classifier can give a significantly better classification performance. As expected, this improvement is more obvious for small sample size datasets and large number of features. 相似文献
2.
MarcelvanRoosmalen MatthiasLocher 《世界电子元器件》2004,(12):75-76
射频存储系统的目标市场有两个,一个是宽带网络,一个是无线局域网:下图介绍的是第一公里的无线宽带接入系统。图的中央有一个中枢(hub),它的周围是一个分布网络。这是一个包括光和电的、数据和模拟结合的网络,这种系统在中国的大城市都有广泛的部署。圆圈是飞利浦开发的一些结点、中枢和分布网络,包括放大器和光电设备。 相似文献
3.
A Ménard R Amouri M Michel F Marcel A Brouillet J Belliveau C Geny L Deforges C Malcus-Vocanson M Armstrong O Lyon-Caen B Mandrand T Dobránsky F Rieger H Perron 《Canadian Metallurgical Quarterly》1997,413(3):477-485
Utilizing cultured lenses from normal and homozygous glutathione peroxidase (GSHPx-1) knockout mice and inhibitors for GSSG Reductase (GSSG Red), 1,3-bis(2-chlorethyl)-1-nitrosourea (BCNU) and catalase (Cat), 3-aminotriazole (3-AT), the ability to degrade H2O2 was examined at two H2O2 concentrations, 300 microM and 80 microM. It was found that GSHPx-1 contributed about 15% to the H2O2 degradation. The Cat contribution was concentration dependent being about 30% at 300 microM H2O2 and approximately 8% to 15% at 80 microM H2O2. GSH loss measured as nonprotein thiol (NP-SH) was shown to be linked to most of the remaining H2O2 degradation accounting for about 54% to 72% of the H2O2 degradation at 300 microM and 80 microM, respectively. However, based on evaluation of the ability of GSH to nonenzymatically degrade H2O2, it can only account for about 36% at 300 microM and 19% at 80 microM H2O2 of the observed lens H2O2 degradation. It is, therefore, concluded that lens GSH must be involved in other reactions either directly or indirectly related to H2O2 degradation. 相似文献
4.
Methyl oleate (18∶1) and linoleate (18∶2) were readily transformed to the correspondinggem-dichlorocyclopropane derivatives in high yield, using triethylbenzylammonium chloride as the phase-transfer catalyst in the
presence of aqueous NaOH and CHCl3. Reaction of dichlorocarbene with methyl 12-hydroxystearate furnished methyl 12-chlorostearate (49%) and 12-O-formylstearate (19%). The hydroxy group in methyl ricinoleate was protected (O-tetrahydropyran-2′-yl) prior to dichlorocyclopropanation of the ethylenic bond. Removal of the protecting group allowed the
hydroxy group to be converted to a chloride,O-acetyl, azido orO-formyl function. Treatment of methyl ricinoleate with thionyl chloride, followed by the reaction with dichlorocarbene gave
the corresponding 12-chloro-dichlorocyclopropane derivative. The dichlorocyclopropane derivative of oleic acid was transformed
to a C19 allenic fatty acid when treated witht-butyl lithium. However, the remaining dichlorocyclopropane derivatives, containing an additional functional group in the
alkyl chain, failed to yield the corresponding allenic derivatives. All derivatives were characterized by a combination of
spectroscopic and chromatographic techniques, including infrared,1H nuclear magnetic resonance (NMR), and13C NMR spectroscopy. 相似文献
5.
Kalinnik Natalia Kiesel Robert Rauber Thomas Richter Marcel Rünger Gudula 《The Journal of supercomputing》2021,77(4):3484-3515
The Journal of Supercomputing - Scientific application codes are often long-running time- and energy-consuming parallel codes, and the tuning of these methods towards the characteristics of a... 相似文献
6.
Elevated temperature Mg-Al-Sr: Creep resistance,mechanical properties,and microstructure 总被引:13,自引:0,他引:13
Eric Baril Pierre Labelle Mihriban Pekguleryuz 《JOM Journal of the Minerals, Metals and Materials Society》2003,55(11):34-39
Mg-Al-Sr-based alloys (AJ alloys) have shown superior creep performance and tensile strength at temperatures as high as 175°
with stresses up to 70 MPa. Mg-6Al-2.4Sr (AJ62x) exhibits an optimum combination of creep resistance and excellent castability,
while AJ62Lx (strontium <2.1) has better ductility than other AJ formulations. The AJ alloy microstructure is characterized
by the Al4Sr-α(Mg) lamellar phase that forms at the interdendritic/grain boundary region of the primary magne sium matrix. Mg-5Al-2Sr
(AJ52x) contains a ternary phase that was tentatively named Al3Mg13Sr. When the strontium level is low in AJ62x, the volume fraction of Al4Sr is reduced, the aluminum supersaturation of the magnesium primary phase increases, and Mg17Al12 forms. In this article, a mechanism is proposed whereby the creep resistance decreases with the strontium level but the tensile
strength and ductility increase.
For more information, contact Eric Baril, Noranda, Noranda Technologies Centre, 240 Hymus Pointe-Claire (Montréal), Québec,
H9R 1G5 Canada; (514) 630-9347; fax (514) 630-9379; e-mail eric.baril@ntc.noranda.com. 相似文献
7.
8.
Jean Marcel Pallo 《Information Processing Letters》2010,111(1):46-50
We generalize the Kleene theorem to the case where nonassociative products are used. For this purpose, we apply rotations restricted to the root of binary trees. 相似文献
9.
10.
Daniel Klan Marcel Karnstedt Katja Hose Liz Ribe-Baumann Kai-Uwe Sattler 《Distributed and Parallel Databases》2011,29(1-2):151-183
Wireless sensor networks are powerful, distributed, self-organizing systems used for event and environmental monitoring. In-network query processors like TinyDB offer a user friendly SQL-like application development. Due to the sensor nodes?? resource limitations, monolithic approaches often support only a restricted number of operators. For this reason, complex processing is typically outsourced to the base station. Nevertheless, previous work has shown that complete or partial in-network processing can be more efficient than the base station approach. In this paper, we introduce AnduIN, a system for developing, deploying, and running complex in-network processing tasks. In particular, we present the query planning and execution strategies used in AnduIN, a system combining sensor-local in-network processing and a data stream engine. Query planning employs a multi-dimensional cost model taking energy consumption into account and decides autonomously which query parts will be processed within the sensor network and which parts will be processed at the central instance. 相似文献