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1.
The microstructures of Cu films deposited by the self-ion assisted, partially ionized beam (PIB) deposition technique under two different accelerating potentials, 0 KeV and 6 KeV, are compared. The 6 KeV film shows a bimodal (111) fiber and (100) fiber texture with an abundance of twin boundaries and a relatively large average grain size with a typical lognormal distribution. The 0 KeV film consists of small, mostly (111) oriented grains with islands of abnormally large (100) grains. The controlling factors for the abnormal growth of the (100) grains are discussed in relation to the observed microstructures, showing that all factors necessary for abnormal (100) growth are present in the films.  相似文献   
2.
Information-Based Evaluation Criterion for Classifier's Performance   总被引:2,自引:0,他引:2  
Kononenko  Igor  Bratko  Ivan 《Machine Learning》1991,6(1):67-80
In the past few years many systems for learning decision rules from examples were developed. As different systems allow different types of answers when classifying new instances, it is difficult to appropriately evaluate the systems' classification power in comparison with other classification systems or in comparison with human experts. Classification accuracy is usually used as a measure of classification performance. This measure is, however, known to have several defects. A fair evaluation criterion should exclude the influence of the class probabilities which may enable a completely uninformed classifier to trivially achieve high classification accuracy. In this paper a method for evaluating the information score of a classifier's answers is proposed. It excludes the influence of prior probabilities, deals with various types of imperfect or probabilistic answers and can be used also for comparing the performance in different domains.  相似文献   
3.
Refractories and Industrial Ceramics - An analysis was carried out of certain aspects of the zone-forming process in the roof brick of open-hearth furnaces. It was established that three fissure...  相似文献   
4.
Materials with controllable multifunctional abilities for optical imaging (OI) and magnetic resonant imaging (MRI) that also can be used in photodynamic therapy are very interesting for future applications. Mesoporous TiO2 sub‐micrometer particles are doped with gadolinium to improve photoluminescence functionality and spin relaxation for MRI, with the added benefit of enhanced generation of reactive oxygen species (ROS). The Gd‐doped TiO2 exhibits red emission at 637 nm that is beneficial for OI and significantly improves MRI relaxation times, with a beneficial decrease in spin–lattice and spin–spin relaxation times. Density functional theory calculations show that Gd3+ ions introduce impurity energy levels inside the bandgap of anatase TiO2, and also create dipoles that are beneficial for charge separation and decreased electron–hole recombination in the doped lattice. The Gd‐doped TiO2 nanobeads (NBs) show enhanced ability for ROS monitored via ?OH radical photogeneration, in comparison with undoped TiO2 nanobeads and TiO2 P25, for Gd‐doping up to 10%. Cellular internalization and biocompatibility of TiO2@x Gd NBs are tested in vitro on MG‐63 human osteosarcoma cells, showing full biocompatibility. After photoactivation of the particles, anticancer trace by means of ROS photogeneration is observed just after 3 min irradiation.  相似文献   
5.
We study and illustrate the techniques of modeling conflict situations when the capabilities of each side may depend on the actions of the partners. We consider conflicts where violating the constraints is physically impossible.  相似文献   
6.
In this paper, we describe the first practical application of two methods, which bridge the gap between the non-expert user and machine learning models. The first is a method for explaining classifiers’ predictions, which provides the user with additional information about the decision-making process of a classifier. The second is a reliability estimation methodology for regression predictions, which helps the users to decide to what extent to trust a particular prediction. Both methods are successfully applied to a novel breast cancer recurrence prediction data set and the results are evaluated by expert oncologists.  相似文献   
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8.
We present a sensitivity analysis-based method for explaining prediction models that can be applied to any type of classification or regression model. Its advantage over existing general methods is that all subsets of input features are perturbed, so interactions and redundancies between features are taken into account. Furthermore, when explaining an additive model, the method is equivalent to commonly used additive model-specific methods. We illustrate the method’s usefulness with examples from artificial and real-world data sets and an empirical analysis of running times. Results from a controlled experiment with 122 participants suggest that the method’s explanations improved the participants’ understanding of the model.  相似文献   
9.
In this paper we report the fabrication of graphitic microstructures in the bulk of diamond using 120-fs-laser pulses at 800 nm wavelength. Polished plates of single crystal diamond and optical quality polycrystalline CVD diamond were used as samples for 3D microstructuring. Under low fluence conditions and focusing a laser beam into the bulk of diamond plates, multipulse irradiation was found to result in the appearance and continuous growth of a laser-modified (graphitized) region from the focal plane towards the laser beam. Controlling the laser fluence and sample translation velocity (scanning beam velocity) allowed high-aspect-ratio ‘graphitic wires’ – microstructures of a few microns in diameter and several hundred micrometers in length – to be fabricated in the bulk of diamond. Physical processes responsible for the continuous growth of microscopic graphitic regions towards a laser beam are discussed. Results of comparative investigations of graphitic microstructures produced by laser pulses of different durations (120 fs and 300 ps) are presented to show the advantages of ultrashort laser pulses in 3D microstructuring of diamond.  相似文献   
10.
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