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51.
Usama Ijaz Bajwa Imtiaz Ahmad Taj Muhammad Waqas Anwar 《Optics Communications》2012,285(21-22):4324-4332
Face recognition being the fastest growing biometric technology has expanded manifold in the last few years. Various new algorithms and commercial systems have been proposed and developed. However, none of the proposed or developed algorithm is a complete solution because it may work very well on one set of images with say illumination changes but may not work properly on another set of image variations like expression variations. This study is motivated by the fact that any single classifier cannot claim to show generally better performance against all facial image variations. To overcome this shortcoming and achieve generality, combining several classifiers using various strategies has been studied extensively also incorporating the question of suitability of any classifier for this task. The study is based on the outcome of a comprehensive comparative analysis conducted on a combination of six subspace extraction algorithms and four distance metrics on three facial databases. The analysis leads to the selection of the most suitable classifiers which performs better on one task or the other. These classifiers are then combined together onto an ensemble classifier by two different strategies of weighted sum and re-ranking. The results of the ensemble classifier show that these strategies can be effectively used to construct a single classifier that can successfully handle varying facial image conditions of illumination, aging and facial expressions. 相似文献
52.
Argha Deb Syed Imtiaz Ahmed Dipak Ghosh Parthasarathi Ghosh 《Acta Physica Hungarica A》2001,13(4):223-227
The three-particle short-range correlation analysis in azimuthal phase space for muon–nucleus interaction at (420 ± 45) GeV in nuclear emul- sions has been presented. The experimental data on three-particle correlation are compared with MC simulated values. 相似文献
53.
Imtiaz Ahmad Mohammad Arsala Khan Mohammad Shakirullah Mohammad Ishaq Rashid Ahmad Habib‐ur‐Rehman 《中国化学会会志》2004,51(4):723-727
A Pakistani coal was de‐polymerized/liquefied in toluene in a 1000 mL micro autoclave. Experiments have been performed in a pool of hydrogen under varying operating conditions of temperature, residence time, hydrogen pressure (cold), coal/solvent ratio and coal particle size. A pronounced effect of all these process variables has been noted on the yields of liquefied products, i.e., THF solubles, n‐pentane solubles, and n‐pentane insolubles. Extraction temperature of 450 °C, residence time of 1 hour, hydrogen pressure of 30 kgf/cm2, coal/solvent ratio of 1:2 and coal particle size of 53–45 μm were found optimum for maximum conversion of Pakistani coal into liquefied products. 相似文献
54.
Sohaila Andleeb Imtiaz‐ud‐Din Muhammad Khawar Rauf Syed Sikander Azam Ihsan‐ul Haq Muhammad Nawaz Tahir Sajjad Ahmad 《应用有机金属化学》2019,33(9)
Heteroleptic triorganobismuth (V) complexes of general formula, R3Bi(OOCR')2 ( 1 – 7 ), where R = C6H5 ( 1 – 3 ), p‐CH3C6H4 ( 4 – 7 ) and R' = 3,5‐Cl2C6H3 ( 1 , 5 ); 3,4,5‐(OCH3)3C6H2 ( 2 , 6 ); 3‐CH3C6H4 ( 3 , 7 ); 2‐OH‐3‐OCH3C6H3 ( 4 ) have been synthesized and fully characterized by FT‐IR, 1H &13C NMR spectroscopy, single crystal X‐ray crystallography and elemental analysis. The molecular geometry observed for the compounds is predominantly distorted trigonal bipyramidal, the fact which was subsequently authenticated through X‐ray analyses for ( 1 – 4 ). All the synthesized compounds have been bio‐assayed for antileishmanial (Leishmania tropica KWH23) and Jack beans urease inhibitory activity, and human Lymphocytes were used to measure the general toxicity. Of these, ( 4 ) proved to be highly effective against the target species (Leishmania tropica KWH23), while being non‐toxic towards the mammalian cells at levels below 0.74 μgmL?1, making it highly promising drug candidate. The high activities for ( 2 , 4 , and 6 ) against Jack beans Urease as compared to the reference standard demonstrate their significance in searching of therapeutic agents in future programs. The significant binding score of ( 2 & 4 ) against H. pylori in molecular docking studies further revealed their importance in future drug discovery processes. 相似文献
55.
Shamila Imtiaz Misbahul Ain Khan Ahsan Sharif Ejaz Ahmed Whei‐Oh Lin Munawar Ali Munawar 《中国化学会会志》2012,59(11):1446-1448
A green chemistry protocol using ethylene glycol and diethylene glycol is developed for the synthesis of dihydropyrimidinones. 相似文献
56.
The present paper investigates the steady flow of an Oldroyd-B fluid. The fluid flow is induced by an exponentially stretched surface. Suitable transformations reduce a system of nonlinear partial differential equations to a system of ordinary differential equations. Convergence of series solution is discussed explicitly by a homotopy analysis method (HAM). Velocity, temperature and heat transfer rates are examined for different involved parameters through graphs. It is revealed that for a larger retardation time constant, the velocity is enhanced and the temperature is lowered. It is noted that relaxation time constant and the Prandtl number enhance the heat transfer rate. 相似文献
57.
58.
T. Hayat M. Rashid M. Imtiaz A. Alsaedi 《Journal of Applied Mechanics and Technical Physics》2017,58(2):214-223
This study is focused on the heat and mass transfer effects in a magnetohydrodynamic (MHD) flow of a viscous nanofluid saturating a porous medium past an exponentially radiating stretching sheet. The governing differential equations are transformed to a system of nonlinear ordinary differential equations by suitable transformations. It is noted that stratification affects the local Nusselt and Sherwood numbers. 相似文献
59.
Mulenga Kalulu Olayinka Oderinde Ying‐Ying Wei Chuan Zhang Imtiaz Hussain Xue‐Lian Han Yong Jiang 《先进技术聚合物》2019,30(8):1922-1932
Combining hydrophobic materials such as polydimethylsiloxane (PDMS), a natural hydrophobic material with typical hydrophilic monomers without using organic solvent remains a big challenge due to their extreme different properties; hence, fabricating a class of silicone hydrogels with two extremes without use of organic solvents could bring us a novel class of silicone hydrogels. Herein, a range of PDMS‐HEMA‐PEGMA hydrogels was prepared from hydroxyl‐terminated PDMS, 2‐hydroxyethylmethacrylate (HEMA), poly (ethylene glycol) methacrylate (PEGMA), and isophorone diisocyanate via condensation and radical copolymerization reactions. The infrared results confirmed the PDMS‐HEMA‐PEGMA network formation, while the hydrophilicity of the as‐prepared block copolymer was dependent on (PDMS‐HEMA)/PEGMA ratio. Increasing the PEGMA content resulted in increased equilibrium water content, phase separation, surface roughness, and tensile strength, while the tensile modulus, elongation at break, optical transmittance, water contact angle, and oxygen permeability (Dk) were decreasing. At PEGMA content of 28.3%, the relative protein adsorption ratio decreased to 20% and 36% for bovine serum albumin and lysozyme, respectively, compared with that of the control (PDMS‐HEMA), suggesting antiprotein adsorption ability. In overall, the results showed that the PDMS‐HEMA‐PEGMA hydrogels not only exhibited remarkable hydrophilicity and suppressed protein adsorption but also maintained higher optical transparency and oxygen permeability (Dk). 相似文献
60.
A lot of interest has been seen in computational methods that provide reliable atom accurate structures of different molecular systems. In this article, we describe the complexation of alprazolam (ALP) with three cyclodextrins, i.e., α-, β- and γ-CD. ROESY spectra showed that no complex was formed between ALP and α-CD however, ring A of ALP formed ICs with β- and γ-CD. Therefore, structures of ALP/β-CD and ALP/γ-CD were obtained by a combination of NMR (2D-ROESY) and computational methods by a quantitative ROESY approach. Here we determined the structures of CD ICs by a method recently used in our laboratory and then the structures were obtained independently by DFT (B3LYP functional and def2-TZVP basis set). The structures obtained by both methods were compared with each other. Results demonstrated that our method provides reasonable structures comparable to DFT, and can be used to obtain highly atom accurate structures of CD inclusion complexes. Quantitative ROESY analysis of MM and MD structures consume less time and are cheap as compared to DFT, which is highly CPU demanding and time taking. Negative values of binding energy showed that the process of inclusion was spontaneous and complexes formed were stable. The large negative value of binding energy for ALP/β-CD as compared to ALP/γ-CD showed a higher binding affinity of ALP towards β-CD. FMO studies also revealed the higher HOMO-LOUMO gap for inclusion complexes as compared to pure ALP. Intermolecular H-bonds formed in both the complexes are also one of the forces responsible for inclusion complex formation. 相似文献