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71.
Fast Classification Networks For Signal Processing 总被引:2,自引:0,他引:2
We present a generalization of the corner classification approach to training feedforward neural networks that allows rapid learning of nonbinary data. These generalized networks, called fast classification (FC) networks, are compared against backpropagation and radial basis function networks and are shown to have excellent performance for prediction of time series and pattern recognition. FC networks do not require iterative training and they can be used in many signal processing applications where fast, nonlinear filtering provides an advantage. 相似文献
72.
ABSTRACT We integrate into a neo-classical multi-period consumer choice model two new elements: (1) storage and holding activities within a household and (2) an "economic landscape" containing many stores at different distances from the house, that sell possibly different product lines at different prices. The theory leads to multipurpose shopping trips in the one-household one-store case. In the one-household many-store model, we prove the existence of optima by an enumeration argument. We describe an iterative maximization process that generates a cost-minimizing "structure" of shopping trips. This "trip structure" defines a pattern of trips of different lengths to purchase different goods at relevant stores, so as to minimize the purchase and contextual (holding plus transport) cost of any level of consumption, with trip frequency and time-spacing determined over the planning horizon. 相似文献
73.
Pradeep P. Phule Srini Raghavan Subhash H. Risbud 《Journal of the American Ceramic Society》1987,70(5):108-C
A discussion of the relative merits and problems of using Ba(OH)2 , BaO, and Ba as starting materials for the synthesis of barium titanate by the alkoxide method is presented. The Ba(OH)2 process is promising because it does not involve the synthesis of barium alkoxide, whereas the BaO (93% pure) process suffers from complex chemical reactions; the impurities in BaO cause unknown effects on the composition and properties of the final ceramic. Use of high-purity Ba metal (99.99%) for the synthesis of barium alkoxide is more desirable since it results in high-purity, ultrafine barium titanate powders. 相似文献
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Although barium studies and CT are useful in assessing abdominal pathology in tuberculosis, imaging findings are not always specific and a histopathological or bacteriological confirmation is often required. The aim of the present study was to evaluate the role of ultrasound (US) guided fine needle aspiration cytology (FNAC) in the diagnosis of abdominal tuberculosis in patients with non-palpable lesions detected on US/CT. FNAC was performed on 31 sites in 30 patients. The sites included enlarged lymph nodes (n = 14), focal lesions in liver (n = 2) and spleen (n = 8), and thickened bowel in the ileocaecal region (n = 7). The results were classified cytomorphologically into four groups: (1) definite evidence of tuberculosis; (2) presumptive evidence of tuberculosis; (3) suggestive of tuberculosis; and (4) negative for tuberculosis. 18 of the 31 FNACs (58%) revealed a positive diagnosis of tuberculosis (definite evidence in nine patients and presumptive evidence in nine patients). 13 of the 31 FNACs (42%) showed either necrosis alone (n = 4) or negative results (n = 9). Zeihl-Neelson staining for acid-fast bacilli on direct smear was positive in only nine patients (29%). Splenic and lymph nodal FNAC had a high sensitivity (87.5% and 78.6%, respectively) in the diagnosis of tuberculosis. None of the bowel and liver FNACs was diagnostic. No complications were encountered. US guided FNAC offers a safe and accurate method of achieving a diagnosis in patients with suspected abdominal tuberculosis who present with radiologically demonstrable but non-palpable lesions, especially those involving lymph nodes and spleen. 相似文献
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A series of soluble aromatic polyesters (polyarylates) containing arylene sulfone ether linkages and having inherent viscosities of 0.36–1.10 dl/g were prepared by the two-phase low temperature polycondensation of 4,4′-[sulfonyl-bis(p-phenyleneoxy)]dibenzoyl chloride and 3,3′-[sulfonylbis(p-phenyleneoxy)]-dibenzoyl chloride with various bisphenols in an organic solvent-aqueous alkaline solution system in the presence of a phase transfer catalyst. Bisphenols 4,4′-[sulfonylbis(p-phenyleneoxy)]diphenol and 3,3′-[sulfonylbis(p-phenyleneoxy)]-diphenol were synthesized in quantitative yields by an improved procedure. The aromatic polyesters prepared were characterized by infrared spectroscopy, elemental analysis, solution viscosity, thermogravimetric analysis, differential scanning calorimetry and X-ray diffraction. The polyesters prepared had glass transition temperatures in the range 150–230°C and initial decomposition temperatures of 397–491°C. They gave transparent, tough and flexible films by the solution casting technique. 相似文献
78.
Ahmad Zuhairi Abdullah Mohamad Zailani Abu Bakar Subhash Bhatia 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(9):1016-1025
The performance of H‐ZSM‐5‐supported bimetallic catalysts with chromium as the base metal in the combustion of ethyl acetate and benzene is reported. A reactor operated from 100 to 500 °C at a gas hourly space velocity (GHSV) of 32 000 h?1 was used for study of the activity. A combination of 1.0 wt% chromium and 0.5 wt% copper yielded a catalyst (Cr1.0Cu0.5/Z) with improved conversion and carbon dioxide yield. Cr2O3 (Cr3+) and CuO (Cu2+) were the predominant metal species in the catalyst. In agreement with the Mars–van Krevelen model, improved reducibility of Cr3+ in the presence of Cu2+ led to an improvement in activity. The copper content in Cr1.0Cu0.5/Z also favored the formation of deep combustion products. Condensation and subsequent growth of coke precursors in the catalyst pores led to the formation of a softer and less aromatic coke fraction while dehydrogenation activity on acid sites formed a harder and more aromatic coke fraction. The use of Cr1.0Cu0.5/Z favored the formation of lower molecular weight intermediates, leading to reduction in formation of softer coke. Copyright © 2005 Society of Chemical Industry 相似文献
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