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141.
In this paper, we study the well‐known Bonferroni mean and develop its generalized aggregation operators in the Pythagorean fuzzy environment. More specifically, by considering the interrelationship between arguments with Pythagorean fuzzy information, we develop the Pythagorean fuzzy Bonferroni mean (PFBM) and some special properties and cases of them are also discussed. Furthermore, taking the multicriteria decision making environment into consideration, we extend the results of PFBM and develop the weighted Pythagorean fuzzy Bonferroni mean (WPFBM). Meanwhile, we also propose an approach for the application of WPFBM. However, during the application of the WPFBM operator, the calculation is very complex and time consuming. Hence, we introduce the multithreading into the application of the WPFBM operator and develop an accelerative calculating algorithm for it. To validate the performance of the accelerative calculating algorithm, we further design the corresponding experimental analysis.  相似文献   
142.
In this article, we present a new method for the synthesis of almost and quasi-orthogonal polynomials of arbitrary order. Filters designed on the bases of these functions are generators of generalised quasi-orthogonal signals for which we derived and presented necessary mathematical background. Based on theoretical results, we designed and practically implemented generalised first-order (= 1) quasi-orthogonal filter and proved its quasi-orthogonality via performed experiments. Designed filters can be applied in many scientific areas. In this article, generated functions were successfully implemented in Nonlinear Auto Regressive eXogenous (NARX) neural network as activation functions. One practical application of the designed orthogonal neural network is demonstrated through the example of control of the complex technical non-linear system – laboratory magnetic levitation system. Obtained results were compared with neural networks with standard activation functions and orthogonal functions of trigonometric shape. The proposed network demonstrated superiority over existing solutions in the sense of system performances.  相似文献   
143.
Phenolic compound profiles were investigated by high-performance liquid chromatography-diode array detector in three vintages to assess genotypic variation in berry skins of six resistant grapevine varieties: “Cabernet Cortis,” “Chancellor,” “Léon Millot,” “Maréchal Foch,” “Monarch,” and “Regent.” The research has revealed a significant difference among the varieties in the total phenolic content, anthocyanins, flavanols, and flavan-3-ols. A clear differentiation of all varieties by means of the polyphenol profile using discriminant analyses has been achieved. “Regent” reached the significantly highest total polyphenol content, as well as total anthocyanin and total flavonol content. The polyphenol profile of “Chancellor” was quite different from all of the other studied varieties. Although being closely related, “Maréchal Foch” and “Léon Millot” showed qualitatively and quantitatively quite different polyphenol contents. No clear connection between the genetic origin of the varieties and their polyphenol profiles has been found.  相似文献   
144.
TestEra: Specification-Based Testing of Java Programs Using SAT   总被引:3,自引:0,他引:3  
TestEra is a framework for automated specification-based testing of Java programs. TestEra requires as input a Java method (in sourcecode or bytecode), a formal specification of the pre- and post-conditions of that method, and a bound that limits the size of the test cases to be generated. Using the method's pre-condition, TestEra automatically generates all nonisomorphic test inputs up to the given bound. It executes the method on each test input, and uses the method postcondition as an oracle to check the correctness of each output. Specifications are first-order logic formulae. As an enabling technology, TestEra uses the Alloy toolset, which provides an automatic SAT-based tool for analyzing first-order logic formulae. We have used TestEra to check several Java programs including an architecture for dynamic networks, the Alloy-alpha analyzer, a fault-tree analyzer, and methods from the Java Collection Framework.  相似文献   
145.
The piezoelectric, microstructural and electrical characteristics of thick PZT films on relatively inert alumina substrates and on two LTCC tapes, i.e., Du Pont 951 and Electro Science Labs 41020 were studied. A thick-film paste was prepared from the pre-reacted PZT powder (PbZr0.53Ti0.47O3) and printed and fired on LTCC tapes and on alumina substrates, respectively. Dielectric permittivities, dielectric losses, remnant polarizations and coercive fields were measured. The dielectric constants (100–150) of thick films fired on LTCC substrates are low. The piezoelectric coefficients d 33 were measured by different methods, i.e. Berlincourt piezometer, interferometry and piezoresponse force microscope (PFM). The d 33 values on LTCC substrates are low (30–70 pm/V) as compared with values obtained on alumina substrates (around 120 pm/V). Lower dielectric constants and piezoelectric coefficients d 33 of films on LTCC substrates are attributed to the formation of phases with a low permittivity due to the diffusion of silica from LTCC substrates into PZT films. The d 33 constants of samples with different thicknesses of PZT layers (from 20 to 160 μm) at first increase with the increasing thickness of PZT layers and then decrease for thicker films. As the cracks in the structure were not observed the reason for the decreasing d 33 values for thicker films is still unclear.  相似文献   
146.
The non-linearity and the noise of thick-film resistors are parameters that can be used to make a prediction of resistor reliability. The noise spectroscopy measurements of thick-film resistors are proposed as a diagnostic tool for the prediction of possible types of failure. The correlation between noise spectral density data and the results of accelerated aging of thick-film resistors at high temperature were made for HS80 and 2000 resistor pastes.  相似文献   
147.
The anthocyanin composition of red grape varieties Vranec, Cabernet Sauvignon, Merlot and Pinot Noir was determined analyzing the skin extracts of the grape berries. The relative content of the identified anthocyanins was calculated and the obtained anthocyanic profiles were compared in terms of acylation and anthocyanidin distribution. The predominant anthocyanin in all varieties was malvidin-3-glucoside ranging from 35.8% in Cabernet Sauvignon to 67.1% in Pinot Noir. Vranec variety was characterized by high proportions of coumaroyl derivatives (22%) and peonidins (13%). The most pronounced difference among the studied grape cultivars was the relative amount of acetate derivatives accounting 35% in Cabernet Sauvignon, 22% in Merlot and 9% in Vranec. Different relationships among the anthocyanin groups of compounds were calculated and considered as parameters for differentiation of the cultivars. The relationship between coumarates and acetates in Vranec was significantly higher compared with Merlot and Cabernet Sauvignon with obtained values of 2.37 versus 0.63 and 0.56, respectively. Moreover, the ratio between delphinidins and peonidins allows clear discrimination between the studied grape cultivars showing the greatest difference.  相似文献   
148.
La1− y Sr y Fe1− x Al x O3−δ perovskites were studied as potential materials for solid-oxide fuel cell (SOFC) cathodes. The phase relations in the LaFeO3–SrFeO3−δ–LaAlO3 system were investigated by X-ray powder diffraction analysis. The defect structure of the La1− y Sr y Fe1− x Al x O3−δ perovskites was investigated by Mössbauer spectroscopy and weight-loss analysis. Relations between the nonstoichiometry and the conductivity of the La1− y Sr y Fe1− x Al x O3−δ perovskites were investigated. The incorporation of aluminum ( x ) into LaFe1− x AlxO3 was found to have no influence on the defect structure but to decrease the conductivity. The incorporation of strontium ( y ) into La1− y Sr y Fe1− x Al x O3−δ promotes the formation of anion vacancies and Fe4+ that lead to higher conductivity.  相似文献   
149.
An efficient numerical technique based upon a surface integral equation formulation for the coupling of bodies of revolution (BORs) to non-BOR geometries for the design of practical microstrip-slot-aperture-coupled dielectric resonator antennas is presented. The moment method matrix fill time and memory requirements are significantly reduced by utilizing Fourier mode basis functions on the BOR together with the spectral domain Green's function for the printed circuit board. Two practical antennas are designed and fabricated. Antenna input impedances predicted by this technique are in good agreement with those of the actual devices. © 1996 John Wiley & Sons, Inc.  相似文献   
150.
Using Successive-Ionic-Layer-Adsorption-and-Reaction deposition technique, TiO2 films on polyvinyl chloride (PVC) and glass substrates were prepared. The photocatalytic and antibacterial activities of TiO2 films on PVC were evaluated by monitoring the photo-decomposition of 2-(phosphonomethylamino)acetic acid and Micrococcus lutes (odor causing bacteria). Photocatalytic degradation of methylene blue under UV source over as-made, hydrothermal and furnace annealed TiO2 films, and commercial TiO2 pellets were examined.  相似文献   
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