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排序方式: 共有177条查询结果,搜索用时 15 毫秒
31.
Fast algorithm for texture discrimination by use of a separable orthonormal decomposition of the co-occurrence matrix 总被引:1,自引:0,他引:1
We consider the problem of texture analysis with a fast algorithm. For that purpose we propose to use coefficients of the decomposition of co-occurrence matrices on an orthonormal and separable basis. We apply this method for texture discrimination, and we thus demonstrate with some examples its efficiency in terms of rapidity, discrimination performance, and robustness. We compare this method with classifiers that use a Fisher linear discrimination on features a priori defined in the co-occurrence matrices. 相似文献
32.
A design of a log periodic SPIFA (spiral planar inverted-F antenna) is proposed. A way of tuning the SPIFA to work in the ISM band (2.45 GHz) is discussed. The purpose of the antenna is to detect any tumor in the liver depending on the change in the conductivity and the permittivity of the liver after being infected. Detecting liver cancer on its early stages will help in the treatment process and makes it much faster as cancer in early stages can be treated easily. The antenna is designed, simulated and measured in a rabbit's liver. The simulated and measured results show great agreement with each other. 相似文献
33.
Neetu Singh Bharat Kumar Allam Dushyant Singh Raghuvanshi Krishna Nand Singh 《Advanced Synthesis \u0026amp; Catalysis》2013,355(9):1840-1848
An expedient and efficient one‐pot three‐component synthesis of 3‐substituted indoles has been developed by the reaction of indoles, active methylene compounds and aldehydes using a catalytic amount of tetrabutylammonium fluoride under solvent‐free conditions. 相似文献
34.
N. A. Ibrahim E. A. Allam M. B. El-Hossamy W. M. El-Zairy 《Polymer-Plastics Technology and Engineering》2013,52(9):905-911
There is a growing need and special attention for using textile products to provide effective protection against such damage of UV-radiation, i.e., skin cancer, sun burn, and photo-aging, in the recent years. In this research work a new approach for upgrading the UV-protective properties of cotton/wool and viscose/wool blended fabrics for high quality/trans seasonal apparel, was investigated. Factors affecting the UVB-protection function of the aforementioned substrates such as type and concentration of finishing additives, as well as subsequent treatment with cu-acetate or dyeing with anionic or cationic dyes were studied. The experimental data show that: i) the enhancement in the UV-protection factor (UPF) of the finished fabrics is determined by the type of finishing additives, i.e., citric acid ≥ aspartic acid ≥ tartaric acid ≥ none, chitosan TEA.HCL ≥ choline chloride ≥ none, β-cyclodextrin CMC-30 PEG-600 > none, and Siligen® WW > W Siligen® PEP ≥ Leomin® NI-ET ≥ none, regardless of the used substrate, ii) UPF values are governed by the type of substrate, i.e., viscose/wool ≥ cotton/wool, irrespective of the used additives, iii) post-treatment with cu-acetate or post-dyeing with the used dyestuffs brings about a dramatic improvement in UPF values, and iv) UPF values are determined by the finishing regime and follow the descending order: Resin finishing → post dyeing > resin finishing → posttreatment with Cu-acetate > resin finishing in presence of additives > resin finishing in absence of additives. 相似文献
35.
Caroline Schwaner Sarah Farhat John Haley Emmanuelle Pales Espinosa Bassem Allam 《International journal of molecular sciences》2022,23(24)
Seawater pH and carbonate saturation are predicted to decrease dramatically by the end of the century. This process, designated ocean acidification (OA), threatens economically and ecologically important marine calcifiers, including the northern quahog (Mercenaria mercenaria). While many studies have demonstrated the adverse impacts of OA on bivalves, much less is known about mechanisms of resilience and adaptive strategies. Here, we examined clam responses to OA by evaluating cellular (hemocyte activities) and molecular (high-throughput proteomics, RNASeq) changes in hemolymph and extrapallial fluid (EPF—the site of biomineralization located between the mantle and the shell) in M. mercenaria continuously exposed to acidified (pH ~7.3; pCO2 ~2700 ppm) and normal conditions (pH ~8.1; pCO2 ~600 ppm) for one year. The extracellular pH of EPF and hemolymph (~7.5) was significantly higher than that of the external acidified seawater (~7.3). Under OA conditions, granulocytes (a sub-population of hemocytes important for biomineralization) were able to increase intracellular pH (by 54% in EPF and 79% in hemolymph) and calcium content (by 56% in hemolymph). The increased pH of EPF and hemolymph from clams exposed to high pCO2 was associated with the overexpression of genes (at both the mRNA and protein levels) related to biomineralization, acid–base balance, and calcium homeostasis, suggesting that clams can use corrective mechanisms to mitigate the negative impact of OA. 相似文献
36.
Electrochemical techniques were used to investigate the effect of cysteine (cys) on the dissolution behavior of Cu10Ni alloy in sulfide-polluted salt water through the analysis of the alloy electrochemical behavior including Tafel polarization and electrochemical frequency modulation (EFM) along with scanning electron microscopy (SEM) and energy dispersive X-ray diffraction (EDX). The results showed that cys acts as a mixed type inhibitor. The dissolution rate decreases with increasing cys concentration and increases with increasing the temperature. An adherent layer of inhibitor molecules on the alloy surface is proposed to account for their inhibitive action. The adsorption of cys on the active cathodic sites was found to follow the Langmuir adsorption isotherm from which the thermodynamic parameters of adsorption and corrosion processes were determined and discussed. A synergistic effect was observed between cys and potassium iodide (KI). EFM data are in good agreement with SEM and EDX results. 相似文献
37.
Modern shared-memory multi-core processors typically have shared Level 2 (L2) or Level 3 (L3) caches. Cache bottlenecks and replacement strategies are the main problems of such architectures, where multiple cores try to access the shared cache simultaneously. The main problem in improving memory performance is the shared cache architecture and cache replacement. This paper documents the implementation of a Dual-Port Content Addressable Memory (DPCAM) and a modified Near-Far Access Replacement Algorithm (NFRA), which was previously proposed as a shared L2 cache layer in a multi-core processor. Standard Performance Evaluation Corporation (SPEC) Central Processing Unit (CPU) 2006 benchmark workloads are used to evaluate the benefit of the shared L2 cache layer. Results show improved performance of the multicore processor’s DPCAM and NFRA algorithms, corresponding to a higher number of concurrent accesses to shared memory. The new architecture significantly increases system throughput and records performance improvements of up to 8.7% on various types of SPEC 2006 benchmarks. The miss rate is also improved by about 13%, with some exceptions in the sphinx3 and bzip2 benchmarks. These results could open a new window for solving the long-standing problems with shared cache in multi-core processors. 相似文献
38.
Kholoud E. Salem Abdelrahman M. Mokhtar Ibrahim Soliman Mohamed Ramadan Basamat S. Shaheen Nageh K. Allam 《International Journal of Hydrogen Energy》2021,46(1):209-220
In this study, a considerable effort has been devoted for the synthesis of Ge-doped ZnO nanorods on FTO as an efficient and robust photoanode material for solar water splitting. A unique, optimized, and ultra-rapid fabrication method to produce uniform nanorods (30–70 nm in diameter) has been demonstrated using radio frequency sputtering followed by electrochemical anodization. The effect of Ge doping on the conductivity, charge carrier concentration, optical, and photoelectrochemical properties of ZnO was investigated using scanning electron microscope (SEM), glancing angle X-ray diffraction (GAXRD), UV–Vis spectrometer, and Mott Schottky analysis. Glancing angle XRD confirmed the presence of wurtzite structure with a preferable orientation around (101) plane, which is of particular interest for many applications. As evidenced by the photoelectrochemical and transient photocurrent measurements, the fabricated Ge-doped ZnO nanorods exhibited enhanced photocurrent (12 mA/cm2) with an exceptional open circuit voltage of ?1.07 VSCE (?0.416 VRHE) under AM1.5G illumination, compared to the undoped ZnO based-photoanodes. Moreover, the Ge-doped ZnO nanorods showed unprecedented photoconversion efficiency of 3.6% under AM1.5G illumination. Therefore, the fabricated Ge-doped ZnO nanorods could be a promising conductive photoanode for water splitting. 相似文献
39.
Bjorn De Sutter Osman Allam Praveen Raghavan Roeland Vandebriel Hans Cappelle Tom Vander Aa Bingfeng Mei 《Journal of Signal Processing Systems》2010,61(2):157-179
This paper presents a memory organization for SDR inner modem baseband processors that focus on exploiting ILP. This memory
organization uses power-efficient, single-ported, interleaved scratch-pad memory banks to provide enough bandwidth to a high-ILP
processors. A system of queues in the memory interface is used to resolve bank conflicts among the single-ported banks, and
to spread long bursts of conflicting accesses to the same bank over time. Bank address rotation is used to spread long bursts
of conflicting accesses over multiple banks. All proposed techniques have been implemented in hardware, and are evaluated
for a number of different wireless communication standards. For the 11a|n benchmarks, the overhead of stall cycles resulting
from unresolved bank conflicts can be reduced to below 2% with the proposed organization. For 3GPP-LTE, the most demanding
wireless standard we evaluated, the overhead is reduced to less than 0.13%. This is achieved with little energy and area overhead,
and without any bank-aware compiler support. 相似文献
40.
A method of effecting an iterative AC load flow as part of a generalized nonlinear state estimator is described. The estimation equations are a redundant set of quadratic algebraic equations when expressed in Cartesian form. Their Taylor expansion contains terms up to the second order. Consequently, the Jacobian and covariance matrices are constant during the iteration procedure. The use of the sparse inverse matrix method reduces the computational requirement. 相似文献