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Mohamed A.-B.A.,Assiut University | Mohamed A.-B.A.,Salman bin Abdulaziz University
Quantum Information Processing | Year: 2013

Quantum correlations, including entanglement and discord with its geometric measure in a three-qubit Heisenberg XY chain, with phase decoherence, are investigated when a nonuniform magnetic field is applied. When the qubits are initially in an unentangled state, the nearest neighbor pairwise correlations are destroyed by phase decoherence, but stationary correlations appear for next-to-neighbor qubits. With an inhomogeneous magnetic field, the stationary correlations appear for nearest neighbor qubits and they disappear for next-to-nearest neighbor qubits. But when the qubits are initially in an entangled state, an inhomogeneous magnetic field can enhance the stationary correlations of next-to-neighbor qubits, but it cannot do so for nearest neighbor qubits. The decoherence effect on stationary correlations is much stronger for next-to-nearest neighbor qubits than it is for nearest neighbor qubits. Finally, a uniform magnetic field can affect the correlations when the qubits are initially in an entangled state, but it cannot affect them when the qubits are initially in an unentangled state. © 2012 Springer Science+Business Media, LLC.


Mohamed A.-B.A.,Assiut University | Mohamed A.-B.A.,Salman bin Abdulaziz University
Annals of Physics | Year: 2012

By using geometric quantum discord (GQD) and measurement-induced nonlocality (MIN), quantum correlation is investigated for two atoms in the non-degenerate two-photon Tavis-Cummings model. It is shown that there is no asymptotic decay for MIN while asymptotic decay exists for GQD. Quantum correlations can be strengthened by introducing the dipole-dipole interaction. The evolvement period of quantum correlation gets shorter with the increase in the dipole-dipole parameter. It is found that there exists not only quantum nonlocality without entanglement but also quantum nonlocality without quantum discord. Also, the MIN and GQD are raised rather than entanglement, and also with weak initial entanglement, there are MIN and entanglement in a interval of death quantum discord. © 2012 Elsevier Inc.


El-Sousy F.F.M.,Salman bin Abdulaziz University | El-Sousy F.F.M.,Electronics Research Institute of Egypt
IEEE Transactions on Industrial Informatics | Year: 2013

In this paper, an intelligent control system using recurrent wavelet-based Elman neural network (RWENN) for position control of permanent-magnet synchronous motor (PMSM) servo drive is proposed to achieve high precision tracking performance and to deal with the existence of uncertainties. The proposed intelligent optimal RWENN control system (IORWENNCS) incorporating an optimal controller, a RWENN controller and a robust controller. Based on the principle of optimal control, a position tracking controller is designed to minimize a quadratic performance index. In addition, a RWENN controller with accurate approximation capability is used to approximate a nonlinear function in the optimal control law. Moreover, a robust controller with adaptive bound estimation algorithm is proposed to confront the approximation error. The online adaptive control laws are derived based on the optimal control technique and Lyapunov stability analysis, so that the stability of the IORWENNCS can be guaranteed. Using the proposed control scheme, the position tracking performance is substantially improved and the robustness to uncertainties can be obtained as well. All control algorithms are implemented in a TMS320C31 DSP-based control computer. The simulation and experimental results confirm that the proposed IORWENNCS grants robust performance and precise tracking response regardless of load disturbances and PMSM uncertainties. © 2005-2012 IEEE.


El-Sousy F.F.M.,Salman bin Abdulaziz University | El-Sousy F.F.M.,Electronics Research Institute of Egypt
IEEE Transactions on Industrial Informatics | Year: 2013

In this paper, an adaptive dynamic sliding-mode control system (ADSMCS) with recurrent radial basis function network (RRBFN) for indirect field-orientation control induction motor (IM) drive is proposed. The ADSMCS comprises a dynamic sliding-mode controller (DSMC), an RRBFN uncertainty observer and a robust controller. The DSMC is proposed to reduce the chattering phenomenon. However, due to the uncertainty bound being unknown of the switching function for the DSMC, an ADSMCS is proposed to increase the robustness and improve the control performance of IM drive. In the ADSMCS, an RRBFN uncertainty observer is used to estimate an unknown nonlinear time-varying function of lumped parameter uncertainty online. Moreover, the adaptive learning algorithms for the RRBFN are derived using the Lyapunov stability theorem to train the parameters of the RRBFN online. Furthermore, a robust controller is proposed to confront the uncertainties including approximation error, optimal parameter vector and higher order term in Taylor series. A computer simulation and an experimental system are developed to validate the effectiveness of the proposed ADSMCS. All control algorithms are implemented in a TMS320C31 DSP-based control computer. The simulation and experimental results confirm that the ADSMCS grants robust performance and precise response regardless of load disturbances and IM uncertainties. © 2005-2012 IEEE.


Elsabee M.Z.,Cairo University | Abdou E.S.,Egyptian Food Technology Research Institute | Abdou E.S.,Salman bin Abdulaziz University
Materials Science and Engineering C | Year: 2013

Chitosan is a biodegradable biocompatible polymer derived from natural renewable resources with numerous applications in various fields, and one of which is the area of edible films and coatings. Chitosan has antibacterial and antifungal properties which qualify it for food protection, however, its weak mechanical properties, gas and water vapor permeability limit its uses. This review discusses the application of chitosan and its blends with other natural polymers such as starch and other ingredients for example essential oils, and clay in the field of edible films for food protection. The mechanical behavior and the gas and water vapor permeability of the films are also discussed. References dealing with the antimicrobial behavior of these films and their impact on food protection are explored. © 2013 Elsevier B.V.


Ahmad S.,Salman bin Abdulaziz University
Egyptian Journal of Ear, Nose, Throat and Allied Sciences | Year: 2013

Objective: This study sought to determine causative microorganisms of chronic suppurative otitis media (CSOM) and to estimate their susceptibility to antibiotic agents. Materials and methods: One hundred sixty-four (164) patients with unilateral or bilateral active chronic suppurative otitis media were prospectively studied. They had chronic ear discharge and had not received any antibiotics for the previous 5. days. Swabs were taken from all patients, and sent to the Microbiology Department for processing. The specimens were cultured and the isolates were identified using standard microbiological techniques. The antibiotic susceptibilities of the isolates were determined with standard antibiotic discs using the Kirby-bauer disc diffusion method. Results: This study analyzes the causal organisms and their sensitivity to various antibiotics. The major organisms isolated were Methicillin sensitive Staphylococcus aureus [MSSA] (45.1%) followed by Pseudomonas aeruginosa (19.5%). The sensitivity of S. aureus (MSSA) was 79.7% to ciprofloxacin, 69% to cotrimoxazole, and 82.5% to gentamicin whereas the sensitivity of P. aeruginosa was 100% to ceftazidime, 84.4% to ciprofloxacin, 90.6% to gentamicin, and 78.1% to Piperacillin. Majority of the isolates of P. aeruginosa were completely resistant to polymixin B (71.9%) whereas 50% of S. aureus (MSSA) showed resistance to Ampicillin. All Methicillin resistant S. aureus (MRSA) isolates showed 100% resistance to Ampicillin, Augmentin and cephalothin. Among the available topical antibiotic preparations for use in the ear, we found gentamicin and ciprofloxacin as the best choices. Conclusion: The study of microbial pattern and their antibiotic sensitivity determines the prevalent bacterial organisms causing CSOM in the local area to start empirical treatment of otitis media and its complications for a successful outcome, and thus to prevent the emergence of resistant strains. © 2013 .


Alkahtani S.,Salman bin Abdulaziz University
Materials and Design | Year: 2012

An investigation was carried out to determine the effect of Mg, Sr, and Ti additions and artificial T5 and T6 aging treatments on the tensile properties of 319 alloys, with the aim of adjusting these parameters to produce castings with suitable mechanical properties. A statistical DOE model was also developed for the analysis of the correlation between the properties of alloy and independent parameters (composition and aging conditions). The microstructure and fracture of the alloy were examined using scanning electron microscopy. The obtained results show that addition of Ti to alloys containing Mg and Sr produces sounder casting with finer grain size and improves the alloy strength. Excess amounts of Sr, however, deteriorate the tensile properties of alloys containing high Mg content by increasing the total amount of Mg-Sr intermetallic phase and porosity. Fine and dense precipitates with a smaller inter-particle spacing are formed at a lower aging temperature of 150. °C compared to coarse, less dense and more widely dispersed at higher temperature, i.e., 250. °C. The strength of 319 alloys increases with the Mg content and decreases with Sr and aging temperature and time. Increasing the Mg content up to 0.45% enhances the alloy response to heat treatment in the T5 and T6 tempers, more particularly, in the latter case. Fracture of intermetallic phases in the interdendritic regions is mostly brittle, with the formation of microcracks at the interface between Si, Cu, Fe-base intermetallic particles and aluminum. From the statistical analysis, the most effective parameters on the tensile properties were Mg content and aging temperature. The interaction between Mg content and aging temperature and/or aging time was the most influential in this respect. © 2012 Elsevier Ltd.


Alafeefy A.M.,Salman bin Abdulaziz University
Journal of Enzyme Inhibition and Medicinal Chemistry | Year: 2015

Sulfonamide containing molecules are of sound biomedical interest. This work comprises the synthesis and in vitro antitumor testing of new library of 20 such molecules. These compounds were screened for cytotoxic activity against three tumor cell lines MCF-7, HeLa, and HepG2 using MTT assay. The yield was low but all the target compounds exhibited antiproliferative activity better than the standard drug Doxorubicin (CAS-23214-92-8). Seven compounds were more potent and four compounds were as active as the standard drug. There were no great difference between compounds obtained from dimedone and those obtained from cyclohexandione. Also no significant difference found in activity between compounds bearing o-amino ethyl ester side chain and compounds bearing o-amino amide derivatives. However, compounds bearing o-amino-cyano group, although retained considerable activity they were far less active than the preceding two. It was clear that monohydroxy aldehyde derivatives were less active compared with the di and trihydroxy ones. © 2014 Informa UK Ltd. All rights reserved: reproduction in whole or part not permitted.


Alam P.,Salman bin Abdulaziz University
Asian Pacific Journal of Tropical Biomedicine | Year: 2013

Objective: To develop and validate a simple, accurate HPTLC method for the analysis of 8-gingerol and to determine the quantity of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams. Methods: The analysis was performed on 10×20 cm aluminium-backed plates coated with 0.2 mm layers of silica gel 60 F254(E-Merck, Germany) with n-hexane: ethyl acetate 60: 40 (v/v) as mobile phase. Camag TLC Scanner III was used for the UV densitometric scanning at 569. Results: This system was found to give a compact spot of 8-gingerol at retention factor (Rf) value of (0.39±0.04) and linearity was found in the ranges 50-500 ng/spot (r2=0.9987). Limit of detection (12.76 ng/spot), limit of quantification (26.32 ng/spot), accuracy (less than 2 %) and recovery (ranging from 98.22-99.20) were found satisfactory. Conclusions: The HPTLC method developed for quantification of 8-gingerol was found to be simple, accurate, reproducible, sensitive and is applicable to the analysis of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams. © 2013 Asian Pacific Tropical Biomedical Magazine.


Iliyasu A.M.,Salman bin Abdulaziz University | Iliyasu A.M.,Tokyo Institute of Technology
Entropy | Year: 2013

Exploiting the promise of security and efficiency that quantum computing offers, the basic foundations leading to commercial applications for quantum image processing are proposed. Two mathematical frameworks and algorithms to accomplish the watermarking of quantum images, authentication of ownership of already watermarked images and recovery of their unmarked versions on quantum computers are proposed. Encoding the images as 2n-sized normalised Flexible Representation of Quantum Images (FRQI) states, with n-qubits and 1-qubit dedicated to capturing the respective information about the colour and position of every pixel in the image respectively, the proposed algorithms utilise the flexibility inherent to the FRQI representation, in order to confine the transformations on an image to any predetermined chromatic or spatial (or a combination of both) content of the image as dictated by the watermark embedding, authentication or recovery circuits. Furthermore, by adopting an apt generalisation of the criteria required to realise physical quantum computing hardware, three standalone components that make up the framework to prepare, manipulate and recover the various contents required to represent and produce movies on quantum computers are also proposed. Each of the algorithms and the mathematical foundations for their execution were simulated using classical (i.e., conventional or non-quantum) computing resources, and their results were analysed alongside other longstanding classical computing equivalents. The work presented here, combined together with the extensions suggested, provide the basic foundations towards effectuating secure and efficient classical-like image and video processing applications on the quantum-computing framework. © 2013 by the authors.

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