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71.
The performance of memory network pattern classifiers based on a feature frequency-weighting scheme can suffer from an inappropriate arbitrary choice of zero-frequency component in the computation of discriminant functions. This letter assesses the effect of optimising this factor, emphasising the value of optimisation in pairwise class discrimination, which is of particular relevance in the design of efficient hierarchical classifier architectures. 相似文献
72.
M. S. Metwally M. F. El-Hadi M. A. El-Wardany A. Abdel Razik 《Journal of Materials Science》1990,25(10):4223-4225
Samples of an acidic cation exchanger have been prepared by sulphonation of acrylonitrile butadiene styrene copolymer previously cross-linked with phenol-formaldehyde resin. The samples having a cation exchange capacity of 3.48 meqg–1, are being introduced as new catalysts in the hydrolysis of ethyl acetate. The synthesized cation exchanger shows good thermal and chemical stability. Hydrolysis rate constants (K
r values) for the catalysed reaction have been determined. The efficiency of the resin catalyst,q, is shown to be a function of resin concentration. 相似文献
73.
Abdel Rahman Rasha; Sommer Werner; Schweinberger Stefan R. 《Canadian Metallurgical Quarterly》2002,28(2):366
On seeing familiar persons, biographical (semantic) information is typically retrieved faster and more accurately than name information. Serial stage models explain this pattern by suggesting that access to the name follows the retrieval of semantic information. in contrast, interactive activation and competition (IAC) models hold that both processes start together but name retrieval is slower because of structural peculiarities. With a 2-choice go/no-go procedure based on a semantic and a name-related classification, the authors tested differential predictions of the 2 alternative models for reaction times (RTs) and lateralized readiness potentials (LRP). Both LRP (Experiment 1) and RT (Experiment 2) results are in line with IAC models of face identification and naming. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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75.
Corrosion Inhibition and Adsorption Behavior of Sodium Lauryl Ether Sulfate on L80 Carbon Steel in Acetic Acid Solution and Its Synergism with Ethanol 下载免费PDF全文
Mohamed Abdel Moneim Deyab 《Journal of surfactants and detergents》2015,18(3):405-411
The application of sodium lauryl ether sulfate (SLES) as an anionic surfactant and its synergistic combination with ethanol for inhibition of corrosion of L80 carbon steel in acetic acid solutions were investigated by means of potentiodynamic polarization measurements, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and energy‐dispersive X‐ray (EDX) investigations. The inhibition efficiency increases with an increase in concentration of SLES. The adsorption of SLES on the surface of L80 carbon steel obeys the Freundlich isotherm. SLES acts predominately as an anodic inhibitor. XRD, EDX, and SEM examinations of the electrode surface confirmed the adsorption of SLES on the electrode surface. The addition of ethanol with SLES significantly enhances the inhibition effectiveness and generates a strong synergistic effect. 相似文献
76.
A new polymer nanocomposites of an epoxy resin matrix with randomly dispersed nano‐vanadium sesquioxides (V2O3) in various amounts were prepared. The structure of the nanocomposites were characterized by scanning and transmission electron microscopy (SEM and TEM), X‐ray diffraction, hardness, packing factor, extent of filler reinforcement, glass transition temperature, and sound velocity. The percolation threshold in the conductivity of the composites is lesser than 8 wt % and the dielectric constant can reach as high as 103. The resistivity—temperature curve of the composites shows a positive temperature coefficient (PTC) effect. The thermal stability of the composites was examined in terms of thermal gravimetry and differential scanning calorimetry (TG and DTA) and isothermal resistivity–time check. Because of the interfacial interaction among filler particles and the epoxy matrix, the nanocomposites exhibit higher thermal stability. The current–voltage–temperature curves behave as switching current. The temperature increases linearly with the applied voltage which makes this PTC nanocomposites very useful for temperature probe. Finally, electromagnetic interference shielding effectiveness (SE) values have been calculated and measured for the nanocomposites in the frequency range 1–12 GHz. It is found that the SE properties of the nanocomposite improve with increase in wt % of V2O3. A maximum SE of 42 dB for V20 sample at 12 GHz has been achieved. These nanocomposites are potentially useful in suppression of electromagnetic interference and reduction of radar signature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
77.
A. A. El-Neshawy A. M. Rabie A. A. Abdel Baky M. M. Nasr E. A. Emara 《Molecular nutrition & food research》1985,29(3):255-267
Trials were carried out to produce Ras cheese of good quality without the use of starter. Cheese was made from pasteurized cow's milk acidified with lactic acid or citric acid to pH 5.8 alone or coupled with mixing the curd with glucono δ lactone (4.5 g/kg curd). Control cheese was made from milk ripened with a starter culture of S. lactis. Resultant cheeses showed poor body and texture, weak flavour intensity and low levels of soluble nitrogen compounds and free volatile fatty acids. Incorporation into the cheese curd of mixtures containing Fromase 100 (fungal protease) and Piccantase B (fungal lipase) or Fromase 100 and Capalase K (animal lipase) enhanced flavour intensity, improved body characteristics and accelerated the formation of both soluble nitrogen compounds and free volatile fatty acids. The organoleptic properties of the experimental cheeses with added enzymes were comparable to those of the control cheese. 相似文献
78.
79.
Kavita Mathur David Hinks Abdel‐Fattah M. Seyam Robert Alan Donaldson 《Color research and application》2009,34(3):225-232
Jacquard woven fabrics are made from colored yarns and different weaves for designing complex pictorial and other patterning effects. The final visualized color effect is the result of assigning weave designs to different areas of the pattern to be created. The current practice in creating Jacquard woven fabric designs is to produce many samples in a trial‐and‐error attempt to match artwork colors. An ability to simulate accurately the appearance of a design prior to manufacture is highly desirable to reduce trial‐and‐error sample production. No automated accurate digital color methodology is yet available to assist designers in matching the patterned woven fabric to the desired artwork. To achieve this, we developed a geometrical model to predict the color contribution of each yarn on the face of the fabric. The geometrical model combined with a Kubelka‐Munk based color mixing model allowed the prediction of the reflectance properties of the final color for a given design. We compared the predicted and experimental values of the reflectance properties for a range of fabrics using the same geometric model with three separate color mixing models. The geometrical model combined with a log‐based color mixing model produced reasonable agreement between predicted and measured ΔEab, with an average ΔEab of approximately five. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 225–232, 2009 相似文献
80.