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排序方式: 共有1263条查询结果,搜索用时 15 毫秒
71.
Future trends in data mining 总被引:3,自引:1,他引:3
Hans-Peter Kriegel Karsten M. Borgwardt Peer Kröger Alexey Pryakhin Matthias Schubert Arthur Zimek 《Data mining and knowledge discovery》2007,15(1):87-97
Over recent years data mining has been establishing itself as one of the major disciplines in computer science with growing
industrial impact. Undoubtedly, research in data mining will continue and even increase over coming decades. In this article,
we sketch our vision of the future of data mining. Starting from the classic definition of “data mining”, we elaborate on
topics that — in our opinion — will set trends in data mining. 相似文献
72.
C.‐A. Fustin P. Guillet U. S. Schubert J.‐F. Gohy 《Advanced materials (Deerfield Beach, Fla.)》2007,19(13):1665-1673
Supramolecular copolymers have become of increasing interest in recent years for the search of new materials with tunable properties. In particular, metallo‐supramolecular block copolymers—copolymers in which the blocks are linked together by a metal–ligand complex—have seen important progresses, allowing better control over the synthetic strategies for various architectures, and providing a better understanding of the parameters governing their self‐assembly. We review here recent developments on the synthesis and self‐assembly of such materials achieved in this field. 相似文献
73.
C. Guerrero‐Sanchez T. Lara‐Ceniceros E. Jimenez‐Regalado M. Raşa U. S. Schubert 《Advanced materials (Deerfield Beach, Fla.)》2007,19(13)
The use of ionic liquids as carriers of magnetorheological fluids is described by Schubert and co‐workers on p. 1740. Combining the properties of ionic liquids with magnetorheological technology may lead to new, “smart” fluids for application in medical therapies, engineering devices, or multiphase biological and chemical systems. In the presence of a magnetic field the fluids behave as solids owing to a stronger interaction between their suspended magnetic particles. In the absence of the magnetic field, they become liquids again in a fully reversible process. 相似文献
74.
75.
George Makrides Bastian Zinsser George E. Georghiou Markus Schubert Jürgen H. Werner 《Solar Energy Materials & Solar Cells》2009,93(6-7):1095-1099
This paper describes field investigations performed and the evaluated temperature behaviour of 13 different types of PV modules, which have been exposed to real conditions both in Stuttgart, Germany and Nicosia, Cyprus. The temperature coefficients have been evaluated in two ways. The first using direct outdoor measurements and the second through the application of data manipulation techniques on the measured meteorological and operational data collected by the installed sensors present at the test sites. The results from the two methods are finally compared and validated demonstrating the reasonable agreement with the manufacturers’ data. 相似文献
76.
Schubert M.B. Mohring H.-D. Lotter E. Bauer G.H. 《Electron Devices, IEEE Transactions on》1989,36(12):2863-2867
The authors report a detailed investigation of correlations between Urbach energies from photothermal deflection spectroscopy and Raman half-widths of transverse optic (TO)-like Si-Si modes as a measure of silicon matrix disorder in glow-discharge amorphous hydrogenated silicon (a-Si:H) and a-SiGe:H, as well as in glow-discharge and sputtered a-SiC:H and a-SiN:H. A corresponding decrease in TO full width at half-maximum (FWHM) and Urbach energy E 0 for soft deposition techniques yields bond angle distributions as narrow as 8.5° for the best a-Si:H films. Even at the lowest levels of nitrogen incorporation, simultaneous increases in E 0 and TO-like half-widths indicate that lattice distortions occur due to threefold coordination of nitrogen in the a-Si:H matrix. In contrast, no deviation of silicon TO-FWHM could be detected in a-SiC:H of up to 35 at.% of carbon content, whereas Urbach edges broaden in a well-known manner that is interpreted in terms of -CH3 incorporation into the amorphous network. Diborane doping and sputter deposition, however, give rise to lattice distortions in a-SiC:H, which reflects changes in the carbon coordination 相似文献
77.
Jongho Lee Carmel Majidi Bryan Schubert Ronald S Fearing 《Journal of the Royal Society Interface》2008,5(25):835-844
Gecko-inspired microfibre arrays with 42 million polypropylene fibres cm(-2) (each fibre with elastic modulus 1 GPa, length 20 microm and diameter 0.6 microm) were fabricated and tested under pure shear loading conditions, after removing a preload of less than 0.1 N cm(-2). After sliding to engage fibres, 2 cm2 patches developed up to 4N of shear force with an estimated contact region of 0.44 cm2. The control unfibrillated surface had no measurable shear force. For comparison, a natural setal patch tested under the same conditions on smooth glass showed approximately seven times greater shear per unit estimated contact region. Similar to gecko fibre arrays, the synthetic patch maintains contact and increases shear force with sliding. The high shear force observed (approx. 210 nN per fibre) suggests that fibres are in side contact, providing a larger true contact area than would be obtained by tip contact. Shear force increased over the course of repeated tests for synthetic patches, suggesting deformation of fibres into more favourable conformations. 相似文献
78.
In wireless networks, users are typically coupled by interference. Hence, resource allocation can strongly depend on receive strategies, such as beamforming, CDMA receivers, etc. We study the problem of minimizing the total transmission power while maintaining individual quality-of-service (QoS) values for all users. This problem can be solved by the fixed-point iteration proposed by Yates (1995) as well as by a recently proposed matrix-based iteration (Schubert and Boche, 2007). It was observed by numerical simulations that the matrix-based iteration has interesting numerical properties, and achieves the global optimum in only a few steps. However, an analytical investigation of the convergence behavior has been an open problem so far. In this paper, we show that the matrix-based iteration can be reformulated as a Newton-type iteration of a convex function, which is not guaranteed to be continuously differentiable. Such a behavior can be caused by ambiguous representations of the interference functions, depending on the choice of the receive strategy. Nevertheless, superlinear convergence can be shown by exploiting the special structure of the problem. Namely, the function is convex, locally Lipschitz continuous, and an invertible directional derivative exists for all points of interest. 相似文献
79.
The authors investigated the impact of response activation on dual-task performance by presenting a subliminal prime before the stimulus in Task 2 (S2) of a psychological refractory period (PRP) task. Congruence between prime and S2 modulated the reaction times in Task 2 at short stimulus onset asynchrony despite a PRP effect. This Task 2 congruence effect was paralleled by a Task 1 congruence effect and emerged exclusively under conditions of cross talk, whereas it did not occur under dual-task conditions preventing cross talk between tasks. This suggests that response activation operates during the PRP in dual tasks and affects the response times in Task 2 via cross talk between common processing elements at prebottleneck stages but not by directly affecting the postbottleneck stages. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
During electrochemical oxidation of ReS2 crystals the anodic photocurrent in aqueous electrolytes increases up to 140-fold. This phenomenon is accompanied by the formation of an unstable Re2O7 surface layer and a characteristic change of the photocurrent spectrum in the near UV. This is explained in terms of the formation of a heterojunction between ReS2 and Re2O7. Upon addition of the I–/I
3
–
redox couple a temporarily working electrochemical solar cell is obtained. Since the observed quantum efficiency exceeded the theoretical expectation, further studies of the interfacial quantum processes were made. It turned out that the enhancement effect is due to light collection by scattering processes in the highly refractive Re2O7 film and at the epoxy insulation. 相似文献