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51.
Ashour Amira S. Nagieb Reham Mohamed El-Khobby Heba A. Abd Elnaby Mustafa M. Dey Nilanjan 《Multimedia Tools and Applications》2021,80(2):2583-2597
Multimedia Tools and Applications - Automated segmentation has an essential role in detecting several diseases, such as skin lesions. In segmentation, the active contour (AC) is an efficient method... 相似文献
52.
Afandi Ahmad Abbes Amira Paul Nicholl Benjamin Krill 《Journal of Real-Time Image Processing》2013,8(3):327-340
This paper presents a combination of novel feature vectors construction approach for face recognition using discrete wavelet transform (DWT) and field programmable gate array (FPGA)-based intellectual property (IP) core implementation of transform block in face recognition systems. Initially, four experiments have been conducted including the DWT feature selection and filter choice, features optimisation by coefficient selections and feature threshold. To examine the most suitable method of feature extraction, different wavelet quadrant and scales have been evaluated, and it is followed with an evaluation of different wavelet filter choices and their impact on recognition accuracy. In this study, an approach for face recognition based on coefficient selection for DWT is presented, and the significant of DWT coefficient threshold selection is also analysed. For the hardware implementation, two architectures for two-dimensional (2-D) Haar wavelet transform (HWT) IP core with transpose-based computation and dynamic partial reconfiguration (DPR) have been synthesised using VHDL and implemented on Xilinx Virtex-5 FPGAs. Experimental results and comparisons between different configurations using partial and non-partial reconfiguration processes and a detailed performance analysis of the area, power consumption and maximum frequency are also discussed in this paper. 相似文献
53.
The goal of this paper is threefold: (i) propose a novel face and fingerprint feature modeling using the structural hidden Markov models (SHMMs) paradigm, (ii) explore the use of some feature extraction techniques such as ridgelet transform, discrete wavelet transform with various classifiers for biometric identification, and (iii) determine the best method for classifier combination. The experimental results reported in both fingerprint and face recognition reveal that the SHMMs concept is promising since it has outperformed several state-of-the-arts classifiers when combined with the discrete wavelet transform. Besides, this study has shown that the ridgelet transform without principal components analysis (PCA) dimension reduction fits better with the support vector machines (SVMs) classifier than it does with the SHMMs in the fingerprint recognition task. Finally, these results also reveal a small improvement of the bimodal biometric system over unimodal systems; which suggest that a most effective fusion scheme is necessary. 相似文献
54.
Pavel Solopov Ruben Manuel Luciano Colunga Biancatelli Christiana Dimitropoulou John D. Catravas 《International journal of molecular sciences》2021,22(11)
We developed two models of chemically induced chronic lung injury and pulmonary fibrosis in mice (intratracheally administered hydrochloric acid (HCl) and intratracheally administered nitrogen mustard (NM)) and investigated male–female differences. Female mice exhibited higher 30-day survival and less weight loss than male mice. Thirty days after the instillation of either HCl or NM, bronchoalveolar lavage fluid displayed a persistent, mild inflammatory response, but with higher white blood cell numbers and total protein content in males vs. females. Furthermore, females exhibited less collagen deposition, milder pulmonary fibrosis, and lower Ashcroft scores. After instillation of either HCl or NM, all animals displayed increased values of phosphorylated (activated) Heat Shock Protein 90, which plays a crucial role in the alveolar wound-healing processes; however, females presented lower activation of both transforming growth factor-β (TGF-β) signaling pathways: ERK and SMAD. We propose that female mice are protected from chronic complications of a single exposure to either HCl or NM through a lesser activation of TGF-β and downstream signaling. The understanding of the molecular mechanisms that confer a protective effect in females could help develop new, gender-specific therapeutics for IPF. 相似文献
55.
Non-ionic maleate surfmer (M1) was prepared via ring opening reaction of maleic anhydride with hexanol followed by esterfaction with polyethylene glycol. The prepared surfmer was homo-polymerized and copolymerized with methyl methacrylate (M2) at different conditions using TiO2 and V2O5 as catalysts in presence of O2 or N2. The chemical structure of the prepared surfmer, homo-polymer and copolymer were confirmed by FT-IR, 13C and 1H NMR. The molecular weights of the prepared polymers were measured using Gel Permeation Chromatography (GPC) and their thermal gravimetric analysis (TGA) was determined. TGA indicated a higher thermal stability for the copolymers M1M2TN and M1M2VO relative to the pure polymethylmethacrylate (PMMA). The interfacial tension for the prepared surfmer and the copolymer was measured. The optimum conditions which resulted in 64.2% and 63.8% conversion were 20% w/w TiO2 in N2 and 10% w/w V2O5 in O2 at 80?°C for 4?h with M1/M2 molar ratio of 1:1. 相似文献
56.
57.
S. P. Altintas A. Amira C. Terzioglu 《Journal of Superconductivity and Novel Magnetism》2013,26(5):1461-1465
The La0.7?x Sm x Ca0.3MnO3 with x=0.0 and 0.1 compounds were fabricated by compositional solid state reaction method and investigated for their structural and magnetoelectrical properties. The samples are characterized structurally by X-ray diffraction, scanning electron microscope, and energy dispersive X-ray spectrometer. The electrical and magnetotransport properties of bulk samples have been investigated in the temperature range 5–300 K and a magnetic field up to 7 T. The metal–insulator transition temperature, T MI, decreased with samarium (Sm) doping and also it is increased slightly with the application of magnetic field. The results of Sm doped LCMO compound showed that the maximum magneto resistance (MR) is about 54 % and it appears near the transition temperature. 相似文献
58.
N. Mahamdioua A. Amira S. P. Altintas A. Saoudel Y. Boudjadja L. Amirouche A. Varilci C. Terzioglu 《Journal of Superconductivity and Novel Magnetism》2013,26(5):1441-1444
Samples of La1.4Ca1.6Mn2?x Cu x O7 with 0≤x≤0.075 were prepared by a solid state reaction and characterized. The cell parameters and volume increase with increasing doped content in all the samples. The metal–insulator (MI) transition was observed in all the samples except for x=0.075. The doping increases the MI transition temperature and resistivity. The application of a magnetic field increases the transition temperature. It can be referred to the suppression of the ferromagnetic–insulator state around it. The magnetoresistance (MR) of the undoped and 0.025 Cu-doped samples is observed on a wide range of temperatures (3.5–283 K). The undoped one exhibits a maximum value of 39.7 % at 5.07 K under 5 T. The 0.025 Cu-doped one exhibits a maximum value of 40.65 % at 44 K in the same magnetic field. No MR effect is shown for the 0.05 doped sample. The 0.075 doped sample exhibits a small negative MR behavior and a second peak of resistivity at a very low temperature. 相似文献
59.
Amira M. El‐Shafei Moustafa M.G. Fouda Dierk Knittel Eckhard Schollmeyer 《应用聚合物科学杂志》2008,110(3):1289-1296
A water‐soluble carboxymethyl chitosan was prepared with a view to develop a multifunctional finish on cotton. Carboxymethyl chitosan (CMCTS) was synthesized by chemical reaction of chitosan with monochloroacetic acid under alkaline condition. The water soluble CMCTS was applied to cationized cotton with different concentrations. The treated fabrics were characterized through monitoring the textile physical properties and for the antibacterial activity against Escherichia coli DSMZ 498 and Micrococcus luteus ATCC 9341. The results obtained show that the physical properties of the treated fabrics are improved by increasing the CMCTS concentration, as well as the antibacterial activity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
60.
Christiana Buxton John E Hagan 《Journal of the International Society of Sports Nutrition》2012,9(1):1-8