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51.
Jacob Goldberger Shiri Gordon Hayit Greenspan 《IEEE transactions on image processing》2006,15(2):449-458
In this paper, we combine discrete and continuous image models with information-theoretic-based criteria for unsupervised hierarchical image-set clustering. The continuous image modeling is based on mixture of Gaussian densities. The unsupervised image-set clustering is based on a generalized version of a recently introduced information-theoretic principle, the information bottleneck principle. Images are clustered such that the mutual information between the clusters and the image content is maximally preserved. Experimental results demonstrate the performance of the proposed framework for image clustering on a large image set. Information theoretic tools are used to evaluate cluster quality. Particular emphasis is placed on the application of the clustering for efficient image search and retrieval. 相似文献
52.
The regular associated solution model for binary systems has been modified by incorporating the size of the complex as an
explicit variable. The thermodynamic properties of the liquid alloy and the interactions between theA
μB type of complex and the unassociated atoms in anA-B binary have been evaluated as a function of relative size of the complex using the activity coefficients at infinite dilution
and activity data at one other composition in the binary. The computational procedure adopted for determining the concentration
of clusters and interaction energies in the associated liquid is similar to that proposed by Lele and Rao. The analysis has
been applied to the thermodynamic mixing functions of liquid Al-Ca alloys believed to contain Al2Ca associates. It is found that the size of the cluster significantly affects the interaction energies between the complex
and the unassociated atoms, while the equilibrium constant and enthalpy change for the association reaction exhibit only minor
variation, when the equations are fitted to experimental data. The interaction energy between unassociated free atoms remains
virtually unaltered as the size of the complex is varied between extreme values. Accurate data on free energy, enthalpy, and
volume of mixing at the same temperature on alloy systems with compound forming tendency would permit a rigorous test of the
proposed model. 相似文献
53.
T. Jacob and K. Leonard (1986) reported that children of alcoholic fathers were comparable to children of depressed fathers in their psychosocial functioning. These results, however, were based on a relatively homogeneous sample. In the current study, previous results were extended by examining a sample of alcoholic fathers who were not screened for additional paternal psychiatric disorders or for major maternal psychopathology. Children in the unscreened and screened samples could not be distinguished in their functioning, and the majority of children of alcoholic fathers were functioning in the normal range of the Child Behavior Checklist. Given the heterogeneous adjustment in children of alcoholic fathers, the authors examined a range of factors that might protect against or exacerbate the risk associated with paternal alcoholism. Maternal depression and certain demographic characteristics were associated with poorer child functioning, particularly for male children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
The chromium content in foods is relatively low and the most foods have a content below 0.1 ppm. Only spices, cacao, cacao products, poppy and whole meal products contain higher contents. The often published high chromium content of corn germ oil could not be verified. We did not find any chromium enrichment in the entrails of a cow. In addition the chromium contents of each food are strong deviated. The analysed values were sometimes lower than in literature. We expect that the elder values are higher because of different contaminations in some cases. 相似文献
55.
C. Schönbauer Dipl.-Ing. 《e & i Elektrotechnik und Informationstechnik》2003,120(10):304-306
The new law for the support of electricity produced by renewable sources in Austria (Ökostromgesetz) which came into force with the beginning of 2003, shows its impacts already after the first months. Investments into wind power have increased considerably. These will be accompanied by activities for electricity production by biomass and biogas. The 4%-target quota will probably be reached earlier than the 2008 target period of the law. 相似文献
56.
L. Valade I. Malfant A. Glaria J.-F. Lamère B. Garreau de Bonneval D. de Caro S. Vincendeau K. Jacob M.-L. Doublet A. Zwick 《Journal of Low Temperature Physics》2006,142(3-4):449-452
For the development of new crystal and electronic structures in molecular conductors, dimeric tetrathiafulvalene (TTF) and
tetraselenafulvalenes (TSFs)1–3 linked by single or double methyl antimony bridge(s) have been prepared and their neutral crystal structures have been investigated.
The donor2 (cis-2) forms a metallic cation radical salt with tetracyanoquinodimethane (TCNQ) containing one-dimensional array interactions. 相似文献
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