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BN-GEPSO:Learning Bayesian Network Structure Using Generalized Particle Swarm Optimization

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Computers, Materials & Continua 2023年第5期75卷 4217-4229页

作者： Muhammad saad Salman Ibrahim M.Almanjahie AmanUllah Yasin Ammara Nawaz Cheema Air University Islamabad44000Pakistan Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia

At present Bayesian Networks(BN)are being used widely for demonstrating uncertain knowledge in many disciplines,including biology,computer science,risk analysis,service quality analysis,and *** they suffer from the problem that when the nodes and edges increase,the structure learning difficulty increases and algorithms become *** solve this problem,heuristic optimization algorithms are used,which tend to find a near-optimal answer rather than an exact one,with particle swarm optimization(PSO)being one of *** is a swarm intelligence-based algorithm having basic inspiration from flocks of birds(how they search for food).PSO is employed widely because it is easier to code,converges quickly,and can be parallelized *** use a recently proposed version of PSO called generalized particle swarm optimization(GEPSO)to learn bayesian network *** construct an initial directed acyclic graph(DAG)by using the max-min parent’s children(MMPC)algorithm and cross relative average *** used to create a population for theGEPSO optimization ***,we propose a velocity update procedure to increase the efficiency of the algorithmic search *** of the experiments show that as the complexity of the dataset increases,our algorithm Bayesian network generalized particle swarm optimization(BN-GEPSO)outperforms the PSO algorithm in terms of the Bayesian information criterion(BIC)score.

关键词： Bayesian network structure learning particle swarm optimization

Some Geometric Invariants of Pseudo-Spherical Evolutes in the Hyperbolic 3-Space

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Computers, Materials & Continua 2018年第12期57卷 389-415页

作者： H.S.Abdel-Aziz M.Khalifa saad A.A.Abdel-Salam Mathematics Department Faculty of ScienceSohag University82524SohagEgypt Mathematics Department Faculty of ScienceIslamic University of Madinah170 El-MadinahKSA

In this paper,we study the pseudo-spherical evolutes of curves in three dimensional hyperbolic *** use techniques from singularity theory to investigate the singularities of pseudo-spherical evolutes and establish some relationships between singularities of these curves and geometric invariants of curves under the action of the Lorentz ***,we defray with illustration some computational examples in support our main results.

关键词： Pseudo-spherical evolutes evolute curves hyperbolic 3-space

Rapid transaction to load variations of active filter supplied by PV system

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Frontiers in Energy 2014年第3期8卷 335-344页

作者： M. BENADJA S. saad A. BELHAMRA Laboratoire Systemes Electromecaniques Badji-Mokhtar Annaba University B.P. 12 Annaba 23000 Alegria

This paper deals with the analysis and control of a photovoltaic （PV） system connected to the main supply through a Boost converter and shunt active filter supplied by a PV system providing continuous supply of nonlinear load in variation. A robust control of a PV system connected to the grid while feeding a variable nonlinear load is developed and highlighted. This development is based on the control of the Boost converter to extract the maximum power from the PV system using the Perturb and Observe （P and O） algorithm in the presence of temperature and illumination. The proposed modeling and control strategy provide power to the variable nonlinear load and facilitates the transfer of power from solar panel to the grid while improving the quality of energy （harmonic currents compensation, power factor compensation and dc bus voltage regulation）. Validation of the developed model and control strategy is conducted using power system simulator Sim-Power System Blockset Matlab/Simulink. To demonstrate the effectiveness of the shunt active filter to load changes, the method of instantaneous power （pq theory） is used to identify harmonic currents. The obtained results show an accurate extraction of harmonic currents and perfect compensation of both reactive power and harmonic currents with a lower THD and in accordance with the IEEE-519 standard.

关键词： solar panels maximum power point tracking(MPPT) DC/DC converter (Boost) shunt active filter,instantaneous power control power quality harmonics,imbalances reactive energy

Annual dose rate for Qena governorate population due to consume the animal products

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Nuclear Science and Techniques 2010年第2期21卷 76-79页

作者： S. Harb K. Sahalel Din A. Abbady Nagwa saad Physics Department Faculty of Science South Valley University Qena 83523 Egypt

In this work, the natural radionuclide concentrations of the 226Ra, 228Ra, 232Th and 40K were estimated from samples of cattle and poultry fodder, South Valley University farms and Qena Governorate farm, Qena, Upper Egypt. The radionuclide concentrations and annual consumption rate of twenty-nine animal fodders were analyzed using low-level γ-spectrometer, including a mixture fodder, silage, hay, rice straw, and poultry fodder. The irradiation risk of human health was assessed due to indirect ingestion of the beef, milk, poultry and egg, the annual effective dose of the radionuclides for the local consumer was 2.7, 14, 0.1, and 0.14 μSv·y–1, respectively.

关键词：消费者动物产品天然放射性核素剂量率人口家禽饲料动物饲料混合饲料

Database Recovery Technique for Mobile Computing:A Game Theory Approach

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Computers, Materials & Continua 2022年第2期70卷 3205-3219页

作者： Magda M.Madbouly Yasser F.Mokhtar saad M.Darwish Institute of Graduate Studies and Research Alexandria UniversityAlexandriaEgypt Assistant General Manager IT DepartmentEgyptian Petrochemicals Co.AlexandriaEgypt

Contact between mobile hosts and database servers presents many problems in theMobile Database System(MDS).It is harmed by a variety of causes,including handoff,inadequate capacity,frequent transaction updates,and repeated failures,both of which contribute to serious issues with the information system’s ***,error tolerance technicality allows devices to continue performing their functions in the event of a *** aim of this paper is to identify the optimal recovery approach from among the available state-of-the-art techniques in MDS by employing game *** of the presented recovery protocols are chosen and evaluated in order to determine the most critical factors affecting the recovery mechanism,such as the number of processes,the time required to deliver messages,and the number of messages logged-in ***,using the suggested payout matrix,the game theory strategy is adapted to choose the optimum recovery technique for the specified environmental *** NS2 simulatorwas used to carry out the tests and apply the chosen recovery *** experiments validate the proposed model’s usefulness in comparison to other methods.

关键词： Mobile computing game theory decision making mobile database recovery

Coverless Image Steganography Based on Jigsaw Puzzle Image Generation

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Computers, Materials & Continua 2021年第5期67卷 2077-2091页

作者： Al Hussien Seddik saad M.S.Mohamed E.H.Hafez Department of Computer Science Faculty of ScienceMinia UniversityMinya61519Egypt Department of Mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azher UniversityNasr City11884Egypt Department of Mathematics Faculty of ScienceHelwan UniversityCairoEgypt

Current image steganography methods are working by assigning an image as a cover file then embed the payload within it by modifying its pixels,creating the stego ***,the left traces that are caused by these modifications will make steganalysis algorithms easily detect the hidden payload.A coverless data hiding concept is proposed to solve this *** does not mean that cover is not required,or the payload can be transmitted without a ***,the payload is embedded by cover generation or a secret message mapping between the cover file and the *** this paper,a new coverless image steganography method has been proposed based on the jigsaw puzzle image generation driven by a secret ***,the image is divided into equal rows then further divided into equal columns,creating blocks(i.e.,sub-images).Then,according to secret message bits and a proposed mapping function,each block will have tabs/blanks to get the shape of a puzzle piece creating a fully shaped jigsaw puzzle *** that,the generated jigsaw puzzle image is sent to the *** results and analysis show a good performance in the hiding capacity,security,and robustness compared with existing coverless image steganography methods.

关键词： Coverless information hiding Jigsaw puzzle image image steganography data hiding

An efficient synthesis of bis(indolyl)methanes and N,N'-alkylidene bisamides by Silzic under solvent free conditions

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Chinese Chemical Letters 2016年第3期27卷 353-356页

作者： Hanan A.Soliman Ahmed Y.Mubarak saad S.Elmorsy Photochemistry Department National Research Centre Chemistry Department Faculty of ScienceMansoura University

An operationally simple and green method for the synthesis of a wide range of bis（indolyl）methanes,and N,N＇-alkylidene bisamides under mild conditions,with excellent yields using Silzic,has been *** improved method furnishes in good yields bis（indolyl）methanes derivatives starting from indole and aldehydes,or ketones,and N,N＇-alkylidene bisamides derivatives starting from acetamide and *** catalytic system was reused up to three times with the same efficiency.

关键词： Bis(indolyl)methanes N N'-alkylidenebisamides Acetamide Mild conditions Silzic

Modern comprehensive study of the W UMa system TY Boo

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Research in Astronomy and Astrophysics 2015年第4期15卷 501-516页

作者： Magdy M.Elkhateeb Mohamed Ibrahim Nouh Abdel-Naby S.saad Astronomy Department National Research Institute of Astronomy and Geophysics Physics Department College of ScienceNorthern Border University Mathematics Department Preparatory YearQassim University

New three color light curves of TY Boo were acquired during five nights from February to May 2006 in the BVR bandpass using a 50-cm F/8.4 Ritchey- Chr6tien telescope （Ba50） at the Baja Astronomical Observatory （Hungary）, with a 512×512 Apogee AP-7 CCD camera. A photometric solution of these light curves was obtained by means of the Wilson-Devinney code. The results showed that the less massive component is hotter than the more massive one, and the temperature difference between the components is △T -249 K. Long term investigation of the system based on all available data shows two stages of increase and a similar trend for decrease, which appears to be periodic behavior. A set of new light elements yields a new period （P = 0.3171506d） and shows a periodic decrease with the rate dP/dE -- 5.858×10^-12 d cycle-1, 6.742×10^-9 d yr-1 or 0.058 s century-1. The evolutionary status of the system is discussed.

关键词： binaries: eclipsing -- stars: evolution

Catheter ablation for atrial fibrillation in heart failure:untying the Gordian knot

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Journal of Geriatric Cardiology 2021年第4期18卷 297-306页

作者： saad Javed Ioanna Koniari David Fox Chris Skene Gregory YH Lip Dhiraj Gupta Liverpool Centre for Cardiovascular Science University of LiverpoolLiverpool Heart and Chest HospitalLiverpoolUK Division of Cardiovascular Sciences University of ManchesterManchesterUK Cardiology Department University Hospital of ManchesterManchesterUK

Atrial fibrillation(AF) and heart failure(HF) are complex clinical entities that occur concomitantly in a significant population of patients, and their prevalence is rising in epidemic proportions. Traditionally, both rate and rhythm control strategies have been regarded as equivalent in the management of dysrhythmia in this AF-HF cohort with escalation of treatment largely guided by symptoms. Both disorders are involved in an elaborate pathophysiological interplay with shared cardiovascular risk factors that contribute to the development and sustenance of both AF and HF. Recent studies and continued development of evidence to support catheter ablation for AF has brought into question the traditional belief in equivalence between rate and rhythm control. Indeed, recent trials, in particular the CASTLE-AF(Catheter Ablation versus Standard Conventional Therapy in Patients with Left Ventricular Dysfunction and Atrial Fibrillation) study, suggest that catheter ablation for AF improves survival and rates of hospitalisation in patients with concomitant HF and AF, threatening a paradigm shift in the management of this patient cohort. The evident mortality benefit from clinical trials suggests that catheter ablation for AF should be considered as a therapeutic intervention in all suitable patients with the AF-HF syndrome as these patients may derive the greatest benefit from restoration of sinus rhythm. Further research is needed to refine the evidence base, especially to determine which subgroup of HF patients benefit most from catheter ablation and what is the optimal timing.

关键词： Catheter ablation for atrial fibrillation in heart failure:untying the Gordian knot