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排序方式: 共有2219条查询结果,搜索用时 12 毫秒
1.
Multi-valued and universal binary neurons (MVN and UBN) are the neural processing elements with the complex-valued weights and high functionality. It is possible to implement an arbitrary mapping described by partially defined multiple-valued function on the single MVN. An arbitrary mapping described by partially defined or fully defined Boolean function, which can be non-threshold, may be implemented on the single UBN. The quickly converging learning algorithms exist for both types of neurons. Such features of the MVN and UBN may be used for solving the different problems. One of the most successful applications of the MVN and UBN is their usage as basic neurons in the Cellular Neural Networks (CNN). It opens the new effective opportunities in nonlinear image filtering and its applications to noise reduction, edge detection and solving of the super resolution problem. A number of experimental results are presented to illustrate the performance of the proposed algorithms.An erratum to this article can be found at 相似文献
2.
Current operational amplifiers: Basic architecture,properties, exploitation and future 总被引:1,自引:1,他引:0
Igor Mucha 《Analog Integrated Circuits and Signal Processing》1995,7(3):243-255
This review paper describes all major considerations of the design of current operational amplifiers (COAs). It is demonstrated, that the single-input, differential-output COA as the adjoint element to the differentialinput, single-output voltage operational amplifier (VOA) is employable in current processing circuits alike the VOAs in voltage processing circuits. On an example of a basic one-high-gain-stage current-operational-amplifier architecture the procedure and the strategy of the design is explained and the main first and second order properties of this device are described. The paper is concluded showing elementary approaches of the derivation of the exploitation of the COAs in current processing circuits interreciprocal to voltage processing circuits and discussing the considerations of the exploitation of the COAs in VLSI designs. 相似文献
3.
Patrícia Carvalho de Souza André Salim Khayat Igor Chamon Seligmann Rommel Mario Rodríguez Burbano 《Biocell》2008,32(2):207-210
The collared peccary (Tayassu tajacu) is widely distributed over the American continent, being found from the south of the USA to the north of Argentina. In Brazil, it is spread all over the country, being one of the potential species to be raised in captivity. Therefore, the cytogenetic techniques could be a potential tool for reproductive monitoring of animals raised in captivity, mainly when destined for commercial purposes. This study had the objective of determining the chromosome number of two populations raised in captivity and characterizing them by GTG banding. For this purpose, an analysis was made of mitotic metaphases obtained from lymphocyte cultures made from blood samples of 11 animals, six of which from the Northeast and five from the North of Brazil. The results of this analysis showed the same karyotype pattern for the species (2n=30 chromosomes and NF=48), besides corresponding to the South American pattern of the species, i.e., without a translocation between autosomes 1 and 8, chromosome X acrocentric, and no differences were found between the two populations studied. However, chromosomal polymorphisms were observed compared to data from the literature on populations from North and South America. 相似文献
4.
We proposed a design methodology for improved thermophoretic probes that can sample particles with high spatial resolution. A bending vibration analysis for the instantaneous motion of a probe has been done together with direct observation of the probe motion and flow disturbance for systematic study of the effect of different designs on particle sampling. Direct observation of the motion of thermophoretic sampling probes revealed that the probe with a low stiffness would result in inaccurate particle sampling. Based on these, the thermophoretic sampling probe was modified to minimize probe vibration and flow disturbance and this modified design was confirmed to sample particles with higher spatial resolution than the original one by examining transmission electron microscope (TEM) images of particles collected in a flame. 相似文献
5.
Camelia Betianu Florentina A Caliman Maria Gavrilescu Igor Cretescu Corneliu Cojocaru Ioannis Poulios 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(11):1454-1465
BACKGROUND: Heterogeneous photocatalysis is influenced by a number of parameters involving synergistic effects; hence, an experimental strategy design that considers interactions between the main variables is needed. The response surface methodology was applied for the investigation of photodegradation of 20 mg L?1 Orange II in aqueous solutions and for optimization of color removal efficiency. Preliminary studies were performed to identify the parameters to be selected for optimization. RESULTS: The input variables considered for experimental design were: solution initial pH, oxidizing agent (H2O2) initial concentration and UV‐A irradiation time. The multivariate experimental design allowed the development of a quadratic response surface model to be used for the prediction of color removal efficiency over the full range of the experimental region. Under the optimum conditions established in the region of experimentation (pH = 6.9, [H2O2]0 = 183 mg L?1 and t = 32 min), a 100% color removal efficiency was obtained in experiments. CONCLUSIONS: It was found that the variables considered have important effects on color removal efficiency. The results demonstrate that the use of experimental design strategy is indispensable for successful investigation and adequate modeling of the process because the interdependence of the reaction parameters cannot be neglected. Copyright © 2008 Society of Chemical Industry 相似文献
6.
Maya D. Glinchuk Vladislav Skorokhod Igor Bykov Vilnis Dimza Eva erno kova Toma Kala 《Ferroelectrics Letters Section》1994,18(5):191-196
X-band EPR spectra of PLZT 1/65/35 and PLZT 8/65/35 doped with 1% FE3+ were recorded at temperature range -175°C to 200°C. Three types of paramagnetic centers were found. Two of them are in strong axial and rhombic crystal field due to neighboring oxygen and lead vacancies. The other center has symmetry determined by polarization and oxygen octahedra tilt. EPR spectra of PLZT 8/65/35 are in agreement with its glassy behavior. 相似文献
7.
The process of explosive decomposition of silver azide in a pulsed electron radiation field was studied by the method of high-speed time-resolution optical spectroscopy. The criteria of excitation of explosive decomposition were determined. It is shown that in the case of short pulses, the critical parameter is the integral energy of the exciting pulse, whereas with the use of long pulses it is the pulse energy flux density.Published for purposes of discussionKemorovo. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 4, pp. 87–90, July–August, 1992. 相似文献
8.
S. M. Ryabykh V. S. Dolganov K. Sh. Karabukaev 《Combustion, Explosion, and Shock Waves》1993,29(2):201-203
Published data on the initiation of the detonation of explosives by a single impulse of energy (impact, friction, spark or light beam) have been analyzed, using the heat theory of detonation. Supported by experimental work on the initiation of the detonation of explosives by an impulse of fast electrons, a model to describe the athermal initiation of the detonation of silver and lead azides by a dense beam of fast electrons is considered. It is proposed that in this case, the seat of initiation is in the region with a highly excited electron subsystem, formed by the concentration of free electrons and holes, generated by the radiation.Kemerovo. Translated from Fizika Goreniya i Vzryva, Vol. 29, No. 2, pp. 75–77, March–April, 1993. 相似文献
9.
Recent research has shown that multilayer feedforward networks with sigmoidal activation functions are universal approximators, and that this holds for more general activations as well. The mathematical underpinning for these results has been various: Kolmogorov's resolution of Hilbert's thirteenth problem; the Stone-Weierstrass theorem; approximation of Fourier and Radon integral representations; and convergence of probability measures. This paper
The second result extends and simplifies some of the recent results of Stinchcombe and White, at least for the special cases ofL
1 andL
2 functions. 相似文献
Rigorously establishes the robustness of feedforward network realizations. | |
Uses a theorem of Wiener and ideas of translation invariant subspaces to provide conditions for universal approximations toL 1 andL 2 functions by networks, for quite general activation functions. |
10.
A new analytical approach for’ micromechanical modeling of the effective viscoelastic behavior of a’ composite material is
presented. Fractionexponential operators are. used to describe the viscoelastic properties of the constituents. To construct
the corresponding elastic solution, effective field method is used. Effective viscoelastic operators are obtained from the
Volter ra’s elasticity-viscoelasticity correspondence principle. Incompatible deformation that often occurs during the manufacturiig
process is taken intp account. All the formulas are obtained in explicit ready-to-use form. 相似文献