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101.
We present a numerical study of a neural tree learning algorithm, the “triolearning≓ strategy. We study the behaviour of the
algorithm as a function of the size of the training set. The results show that a limited number of examples can be used to
estimate both the network performance and the network complexity that would result from running the algorithm on a large data
set. 相似文献
102.
103.
Chi-Woo Lee Dimitri Lederer Aryan Afzalian Ran Yan Nima Dehdashti Weize Xiong Jean-Pierre Colinge 《Solid-state electronics》2008,52(11):1815-1820
The performances of accumulation-mode and inversion-mode multigate FETs are compared. The influence of gate underlap on the electrical properties is analyzed. Both simulation results and experimental data show that in a device with gate underlap, accumulation-mode devices have a higher current drive, lower source and drain resistance and less process variability than inversion-mode FETs. 相似文献
104.
Jean-Pierre Delahaye 《电信纪事》1996,51(1-2):19-26
This paper presents an overview of the implementation of a difference-set cyclic code (1057,813,34). It is easy to achieve coding and decoding circuits. The decoding lays on the analysis of the composite remainder Rc (x) and the use of a decoding matrix of 33 Boolean equations. The error-correcting algorithm has been improved, so the difference-set cyclic code (1057,813,34) can correct up to 26 random errors instead of the 16 previous random errors found by the theory. Moreover, 3 decoding algorithms have been simulated and allow the comparison of their respective efficiency. The hardware achievement is quite easy because the necessary logical elements such as shift delay registers, positive-and gates, positive-or gates, positive-exclusive-or gates exist as a set of libraries. 相似文献
105.
The radiosity method is one of the most popular rendering algorithms. It allows to simulate interreflections of light accurately between surfaces as energy transfers are well designed. However, this algorithm and its derivatives need to break scenes into a relatively large number of small elements to approximate the illumination function. Even with a very large number of elements, not all the illumination effects can be simulated. In fact, there are always artefacts when modelling sharp shadows, besides shadows falling between mesh vertices can be missed entirely. To reduce the computational cost of such methods and to increase the accuracy of the radiosity solution, adaptive mesh generation is well suited. In this paper, we present a ray-tracing based algorithm for adaptive mesh generation which resolves all the illumination problems without lengthening computation time too much. This method allows a small number of initial elements and increases element density in critical locations while solving the illumination problem. 相似文献
106.
Christophe Dematte?¨ Nicolas Molinari Jean-Pierre Daurès 《Computational statistics & data analysis》2007,51(8):3931-3945
An original method is proposed for spatial cluster detection of case event data. A selection order and the distance from the nearest neighbour are attributed to each point, once pre-selected points have been taken into account. This distance is weighted by the expected distance under the uniform distribution hypothesis. Potential clusters are located by modelling the multiple structural change of the distances on the selection order and the best model (containing one or several potential clusters) is selected using the double maximum test. Finally a p-value is obtained for each potential cluster. With this method multiple clusters of any shape can be detected. 相似文献
107.
George Isabella; Vernier Baptiste; Richard Jean-Pierre; Hausberger Martine; Cousillas Hugo 《Canadian Metallurgical Quarterly》2004,118(3):597
Although evidence exists for a lateralization of song production, few studies have focused on the perceptual aspect of lateralization in songbirds. In the present study, the authors recorded neuronal responses to a variety of species-specific and artificial, nonspecific stimuli in both hemispheres of awake and anesthetized male starlings (Sturnus vulgaris). Recordings were made in the primary auditory area of the songbird brain, the Field L complex. The right hemisphere exhibited significantly more responsive units than the left hemisphere in awake birds, and this difference was significantly reduced in anesthetized birds. Furthermore, clear hemispheric specialization toward categories of behaviorally relevant stimuli and precise parameters of these stimuli were found. The main auditory area of the starling's brain thus appears to show some degree of lateralization. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Theoretical coupling efficiency between a channel waveguide and a single-mode optical fibre using a ball lens is optimized by varying the parameters of the optical system such as the relative position of the components, the refractive index and the size of the lens. A specific software has been used for the optimization. Numerical calculations have been done under the Gaussian approximation of the fields distributions. The losses due to waveguides misalignments with respect to their ideal position have been evaluated. All these theoretical results are compared with those obtained from buttcoupling. 相似文献
109.
Experimental study of heat transfer in oscillating flow 总被引:2,自引:0,他引:2
Pascale Bouvier Jean-Pierre Bardon 《International Journal of Heat and Mass Transfer》2005,48(12):2473-2482
This paper describes an experimental study of heat transfer in oscillating flow inside a cylindrical tube. Profiles of temperature are taken inside the wall and in the fluid from an instrumented test rig, in different conditions of oscillating flow. Profiles obtained allow the observation of the wall effect on heat transfer. A method using the inverse heat conduction principle allows the characterization of local heat transfers at the fluid-solid interface. Finally, a comparison between global and local approaches of heat transfer shows the difficulty of defining a dimensionless heat flux density to model local heat transfer in oscillating flow. 相似文献
110.
In this paper we describe a new function to determine the number of electrons transferred by alloying. HF, the new function proposed, is given by the difference of the partial enthalpies of the two constituents, i.e. HF = h(i) - h(j) - h(i)o and is called the Fermi enthalpy. It is retrieved from data calorimetrically measured. In some way, it describes the change in the enthalpic part of the Fermi energy on alloying. This function is determined for Pd + Ga, Pd + In, Ni + Ga, Ni + In, Pt + In, Au + Al and Ag + Al. The corresponding number of electrons transferred is calculated on stoichiometric considerations. 相似文献