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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
56.
The optical properties of bismuth telluride crystals doped with donor-and acceptor-type impurities are studied. The fact that energy corresponding to the resonance frequency of plasma oscillations of free charge carriers (plasmons) approaches the band-gap energy is detected in the infrared spectral region, where the main elementary excitations in the electronic system of these materials are observed. The mentioned approach of energies varies the intensity of electron-plasmon interaction, which affects the recombination processes in the materials widely used for the fabrication of thermoelectric energy converters. 相似文献
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J.R. Red-Horse T.L. Paez 《Computer Methods in Applied Mechanics and Engineering》2008,197(29-32):2578
This article specifies a virtual structural dynamic subsystem and some systems, as well as mathematical models that approximately simulate them. The purpose is to define a setting for model validations conceived by participants in the Sandia National Laboratories Validation Workshop. Some broad guidelines for the model validations are set, as well as a regulatory requirement to be satisfied by the target system. Participants are directed to present techniques for subsystem model validation, to analytically predict whether or not the regulatory requirement will be met, and to estimate the likelihood of accuracy of the prediction. 相似文献
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Tomer A. Goldin L. Kuflik T. Kimchi E. Schach S.R. 《IEEE transactions on pattern analysis and machine intelligence》2004,30(9):601-612
We propose a model that enables software developers to systematically evaluate and compare all possible alternative reuse scenarios. The model supports the clear identification of the basic operations involved and associates a cost component with each basic operation in a focused and precise way. The model is a practical tool that assists developers to weigh and evaluate different reuse scenarios, based on accumulated organizational data, and then to decide which option to select in a given situation. The model is currently being used at six different companies for cost-benefit analysis of alternative reuse scenarios; we give a case study that illustrates how it has been used in practice. 相似文献
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T. Connolley M. J. Starink P. A. S. Reed 《Metallurgical and Materials Transactions A》2004,35(3):771-783
Notches were machined in specimens of INCONEL 718 by a broaching process, where differing broaching runs led to differing
extents of subsurface deformation and surface roughness. Fatigue tests were carried out at 600 °C with a trapezoidal loading
waveform at 0.25 Hz. The broaching process that led to the more severe subsurface deformation (but lower surface roughness)
showed the worst fatigue performance. Analysis of total strain amplitude in the notch root with the aid of an elastoplastic
finite-element (FE) model showed that the work hardening related to the subsurface deformation caused by the different broaching
can account for the difference in fatigue lives. Differences in initiation and growth behavior were seen for the two broached
finishes as well as for broached and subsequently polished samples. These differences are discussed in terms of a change in
crack growth initiation and growth mechanisms due to the presence of the work-hardened layer. 相似文献