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Computers, Materials & Continua 2020年第2期62卷 525-549页

作者： mohamed abd el-Aziz A.M.Aly Department of Mathematics Faculty of ScienceKing Khalid UniversityAbha61411Saudi Arabia Department of Mathematics Faculty of ScienceHelwan UniversityHelwan-Cairo11795Egypt Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt

This study focusses on the numerical investigations of boundary layer flow for magnetohydrodynamic(MHD)and a power-law nanofluid containing gyrotactic microorganisms on an exponentially stretching surface with zero nanoparticle mass flux and convective *** nonlinear system of the governing equations is transformed and solved by Runge-Kutta-Fehlberg *** impacts of the transverse magnetic field,bioconvection parameters,Lewis number,nanofluid parameters,Prandtl number and power-law index on the velocity,temperature,nanoparticle volume fraction,density of motile microorganism profiles is *** addition,the impacts of these parameters on local skin-friction coefficient,local Nusselt,local Sherwood numbers and local density number of the motile microorganisms are *** results reveal that the power law index is considered an important factor in this *** to neglecting the buoyancy force term,the bioconvection and nanofluid parameters have slight effects on the velocity *** resultant Lorentz force,from increasing the magnetic field parameter,try to decrease the velocity profiles and increase the rescaled density of motile microorganisms,temperature and nanoparticle volume fraction ***,an augmentation of power-law index drops the reduced local skin-friction and reduced Sherwood number,while it increases reduced Nusselt number and reduced local density number of motile microorganisms.

关键词： Bioconvection gyrotactic microorganisms magnetohydrodynamic nanofluid boundary layer power-law

Entropy Generation for Flow and Heat Transfer of Sisko-Fluid Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第1期62卷 37-59页

In the present study,the effects of the magnetic field on the entropy generation during fluid flow and heat transfer of a Sisko-fluid over an exponentially stretching surface are *** similarity transformations are used to transfer the governing partial differential equations into a set of nonlinear-coupled ordinary differential ***-Kutta-Fehlberg method is used to solve the governing *** effects of magnetic field parameter,local slip parameterλ,generalized Biot numberγ,Sisko fluid material parameter,Eckert number Ec,Prandtl number Pr and Brinkman number Br at two values of power law index on the velocity,temperature,local entropy generation number N_(G) and Bejan number Be are ***,the tabular forms for local skin friction coefficient and local Nusselt number under the effects of the physical parameters are *** current results are helpful in checking the entropy generation for *** is found that,an extra magnetic field parameter makes higher Lorentz force that suppresses the *** shear thinning fluids(nelocity *** entropy generation number is more for larger generalized Biot number,magnetic field parameter and Brinkman *** local skin friction coefficient increases as magnetic field parameter and material parameter are increase and it decreases as local slip parameter *** local Nusselt number decreases as magnetic field parameter,local slip parameter and Eckert number are increase,while it increases as material parameter,generalized Biot number and Prandtl number are increase.

关键词： Boundary layer entropy generation exponentially stretching surface magnetic field sisko-fluid

Effective damping of local low frequency oscillations in power systems integrated with bulk PV generation

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Protection and Control of Modern Power Systems 2021年第1期6卷 512-524页

作者： Ahmed Hesham abd el-Kareem mohamed abd elhameed Mahmoud M.elkholy Operation Engineer at New Capital Power Plant New Capital CityEgypt electrical Power and Machines Department Faculty of EngineeringZagazig UniversityZagazigEgypt

High penetration of renewable sources into conventional power systems results in reduction of system inertia and noticeable low-frequency oscillations (LFOs) in the rotor speed of synchronous generators. In this paper, we propose effective damping of LFOs by incorporating a supplementary damping controller with a photovoltaic (PV) generating station, where the parameters of this controller are coordinated optimally with those of a power system stabilizer (PSS). The proposed method is applied to damp local electromechanical modes by studying a system comprising a synchronous generator and a PV station connected to an infinite bus. The PV station is modeled following the instructions of the Western electricity Coordinating Council. The problem is modeled as an optimization problem, where the damping ratio of the electromechanical modes is designed as the objective function. Constraints including upper and lower limits of decision parameters and damping ratio of other modes are considered by imposing penalties on the objective function. Different optimization algorithms are used to pursue the optimal design, such as political, improved gray wolves and equilibrium optimizers. The results validate the effectiveness of the proposed controller with PSS in damping local modes of oscillations.

关键词： Low frequency oscillations Damping controller PV WECC

Text-Independent Algorithm for Source Printer Identification Based on Ensemble Learning

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Computers, Materials & Continua 2022年第10期73卷 1417-1436页

作者： Naglaa F.el Abady mohamed Taha hala H.Zayed Department of Computer Science Faculty of Computers and Artificial IntelligenceBenha University13518Egypt School of Information Technology and Computer Science(ITCS) Nile University12677Egypt

Because of the widespread availability of low-cost printers and scanners,document forgery has become extremely *** or signatures are used to protect important papers such as certificates,passports,and identification *** the origins of printed documents is helpful for criminal investigations and also for authenticating digital versions of a document in today’s *** printer identification(SPI)has become increasingly popular for identifying frauds in printed *** paper provides a proposed algorithm for identifying the source printer and categorizing the questioned document into one of the printer classes.A dataset of 1200 papers from 20 distinct(13)laser and(7)inkjet printers achieved significant identification results.A proposed algorithm based on global features such as the Histogram of Oriented Gradient(HOG)and local features such as Local Binary Pattern(LBP)descriptors has been proposed for printer *** classification,Decision Trees(DT),k-Nearest Neighbors(k-NN),Random Forests,Aggregate bootstrapping(bagging),Adaptive-boosting(boosting),Support Vector Machine(SVM),and mixtures of these classifiers have been *** proposed algorithm can accurately classify the questioned documents into their appropriate printer *** adaptive boosting classifier attained a 96%*** proposed algorithm is compared to four recently published algorithms that used the same dataset and gives better classification accuracy.

关键词： Document forensics source printer identification(SPI) HOG LBP principal component analysis(PCA) bagging AdaBoost

Influence of host age and host deprivation on longevity, egg load dynamics and oviposition rate in Microplitis rufiventris

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Insect Science 2007年第6期14卷 485-495页

作者： ESMAT mohamed HEGAZI GEHAN mohamed abd el-AZIZ AHMED YOUSEF el-SHAZLY WEDAD EMAM KHAFAG Department of Entomology Faculty of Agriculture University of Alexandria Plant Protection Research Institute Sabahia Alexandria Egypt

Adult size, longevity, egg load dynamics and oviposition ofMicroplitis rufiventris Kok. which began their development in the first, second, third （preferred hosts） or fourth （non-preferred hosts） instar larvae of Spodoptera littoralis （Boisd.） were studied. The parasitoid size was largely determined by the initial host size at parasitism. Non-ovipositing females derived from older hosts lived for longer periods than those derived from younger ones. However, the ovipositing females, irrespective of their size, lived for almost the same periods. At emergence, the oviducts of adult females contain a significant amount of mature eggs available for oviposition for a few hours on eclosion day. Egg load increases during the early phase of adult life. The amount of additional mature eggs and rate of egg maturation per hour was greater for wasps derived from preferred hosts compared with those in females derived from non-preferred hosts. The pattern of egg production in M. rufiventris females depended on the availability of hosts for parasitization. Host-deprived females depleted the egg complement with aging; the longer the host deprivation, the lower the oviduct egg load. Marked reduction in both realized or potential fecundity of host-deprived females was observed following host availability. Host privation for more than 3 days induced a marked deficit fecundity pattern through the female＇ s life. The realized fecundity was determined by the interaction among host availability, the number of eggs that are matured over the female＇ s life span, oviposition rate and host size from which the female was derived. These results suggest that：（i） M. rufiventris wasp is a weak synovigenic species; （ii） the maturation of additional eggs is inhibited once the maximum oviduct egg load is reached; （iii） the egg load of the newly emerged female is significantly less than the realized fecundity; and （iv） because M. rufiventris females oviposit fewer eggs when they begin depleting their

关键词： aging egg production host privation longevity Microplitis rufiventris,oviposition Spodoptera littoralis wasp size

Improved RC6 Block Cipher Based on Data Dependent Rotations

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Computers, Materials & Continua 2022年第1期70卷 1921-1934页

作者： Osama S.Faragallah Ibrahim F.elashry Ahmed AlGhamdi Walid el-Shafai S.el-Rabaie Fathi E.abd el-Samie hala S.el-sayed mohamed A.elaskily Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of electrical Communications Faculty of EngineeringKafrelsheikh UniversityKafrelsheikhEgypt Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt Department of Informatics Electronic Research Institute(ERI)CairoEgypt

This paper introduces an Improved RC6(IRC6)cipher for data encryption based on data-dependent *** proposed scheme is designed with the potential of meeting the needs of the Advanced Encryption Standard(AES).Four parameters are used to characterize the proposed *** parameters are the size of the word(w)in bits,the number of rounds(r),the length of the secret key(b)in bytes,and the size of the block(L)in *** main feature of IRC6 is the variable number of working registers instead of just four registers as in RC6,resulting in a variable block size for plaintext and *** IRC6 cipher is designed to improve the robustness against attacks by increasing the diffusion for each round and providing greater security with fewer *** effectiveness of the proposed IRC6 scheme is verified against theoretical *** proposed IRC6 scheme depends on full diffusion and confusion mechanisms regardless of the utilized block *** proposed IRC6 scheme saves 70%of the encryption time and 64%of the decryption time of *** simulation results prove that the IRC6 achieves a better encryption/decryption time compared to the ***,the proposed IRC6 is anticipated to fulfill the market needs and system security requirements.

关键词： Cryptography block cipher RC6,IRC6,AES

Predictors of long-term survival after pancreaticoduodenectomy for peri-ampullary adenocarcinoma: A retrospective study of 5-year survivors

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Hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 443-449页

作者： Ayman el Nakeeb mohamed el Sorogy Helmy Ezzat Rami Said mohamed el Dosoky mohamed abd el Gawad Ahmed M elsabagh Ehab el Hanafy Gastroenterology Surgical Center Mansoura University

Background: Pancreaticoduodenectomy(PD) is the standard curative treatment for periampullary tumors. The aim of this study is to report the incidence and predictors of long-term survival( ≥ 5 years) after PD. Methods: This study included patients who underwent PD for pathologically proven periampullary adenocarcinomas. Patients were divided into 2 groups: group(I) patients who survived less than 5 years and group(II) patients who survived ≥ 5 years. Results: There were 47(20.6%) long-term survivors( ≥ 5 years) among 228 patients underwent PD for periampullary adenocarcinoma. Patients with ampullary adenocarcinoma represented 31(66.0%) of the long-term survivors. Primary analysis showed that favourable factors for long-term survival include age < 60 years old, serum CEA < 5 ng/mL, serum CA 19-9 < 37 U/mL, non-cirrhotic liver, tumor size < 2 cm, site of primary tumor, postoperative pancreatic fistula, R0 resection, postoperative chemotherapy, and no recurrence. Multivariate analysis demonstrated that CA 19-9 < 37 U/mL [OR(95% CI) = 1.712(1.24 8–2.34 8), P = 0.001], smaller tumor size [OR(95% CI) = 1.335(1.032–1.726), P = 0.028] and R0 resection [OR(95% CI) = 3.098(2.095–4.582), P < 0.001] were independent factors for survival ≥ 5 years. The prognosis was best for ampullary adenocarcinoma, for which the median survival was 54 months and 5-year survival rate was 39.0%, and the poorest was pancreatic head adenocarcinoma, for which the median survival was 27 months and 5-year survival rate was 7%. Conclusions: The majority of long-term survivors after PD for periampullary adenocarcinoma are patients with ampullary tumor. CA 19-9 < 37 U/mL, smaller tumor size, and R0 resection were found to be independent factors for long-term survival ≥ 5 years.

关键词： Pancreatic carcinoma Pancreatic head carcinoma Pancreaticodudenectomy Long-term survival

Non-Hodgkin Lymphoma of the Liver:A US Population-based Analysis

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Journal of Clinical and Translational Hepatology 2017年第2期5卷 83-91页

作者： mohamed abd el-Fattah Department of Internal Medicine Faculty of Medicine Suez Canal University Ismailia Egypt

Background and Aims:Non-Hodgkin lymphoma (NHL) of the liver is a rare lymphoid malignancy,accounting for less than 1% of extranodal ***:I conducted an analysis of the U.S Surveillance,Epidemiology,and End Results (SEER) database to evaluate the histological subtypes and the survival outcomes of 785 cases with hepatic NHL between 1973 and ***:There were 785 of 312 459 cases with NHL had a first primary hepatic NHL (0.25%).Of the total 785 cases,the median age at diagnosis was 61 years (range 3-95 years) and male-female ratio of 1.7∶*** most common subtype was diffuse large B cell lymphoma (63.2%).In all patients,the median overall survival (OS) was 33 months (95%CI,22-48 months).The 5-year OS rate for indolent B-cell NHLs was 62%,compared with 44% for an aggressive B-cell NHLs and 42% for T-cell *** median OS improved from 19 months in patients diagnosed in a period 1996-2000 to 60 months when diagnosed between 2006 and 2012 (p ell NHLvariants (aHR 1.73,p =.03) were unfavourable prognostic ***:NHL of the liver comprises about 0.3% of all NHLs and survival was improved in the recent calendar period.

关键词： Non-Hodgkin lymphoma Liver Primary hepatic lymphoma Hepatic neoplasms

Free radical scavenging activity of three different flowers-Hibiscus rosa-sinensis,Quisqualis indica and Senna surattensis

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Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 771-777页

作者： abd el-Moneim mohamed Radwan Afify Hazem mohamed Mahmoud Hassan Biochemistry Department Faculty of AgricultureCairo University

Objective:To evaluate three flowers of Hibiscus rosa-sinensis(***-sinensis),Quisqualis indica(***) and Senna surattensis(***) for their antioxidant activity by different methods in addition to total phenolic,flavonoid and pigment ***:Antioxidant activity of water,ethanol and absolute ethanol extracts of three flowers; ***-sinensis,*** and *** was *** antioxidant activity was assessed by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity,ferrous chelating activity,reducing power,nitric oxide scavenging activity,hydroxyl radical scavenging activity as well as total antioxidant *** flavonoids,total phenols and total pigments including chlorophylls and carotenoids were measured for the three ***:The results showed that the highest total antioxidant capacity at concentration of 500 mg/L was found in *** as 0.479 ± *** activity of ***,*** and *** flower extracts against 1,1-diphenyl-2-picrylhydrazyl radical showed the highest activity of(90.20 ± 0.29)% with 500 mg/*** screening of the three flowers extracts were carried out for alkaloids,flavonoids,saponins,tannins,steroids,glycosides,terpenoids,amino acid and ***-sinensis showed the total phenolic in water extract of(235.77 ± 14.31) mg/100 g,the other two flowers *** and *** had the total phenolic in ethanol extracts of(937.70 ± 25.06) and(850.30 ± 13.81) mg/100 g,*** the other hand total flavonoids were identified in absolute ethanol extracts in the three flowers[(32.83 ± 1.34),(49.24 ± 4.87) and(2.79 ± 0.23) mg/100 g,respectively].Conclusions:The extracts in the constituents of the three flowers could be used as additives as supplement fractions in foods.

关键词： Free radical Antioxidant Hibiscus rosa-sinensis Quisqualis indica Senna surattensis

Wireless Sensor Networks Routing Attacks Prevention with Blockchain and Deep Neural Network

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Computers, Materials & Continua 2022年第3期70卷 6127-6140页

作者： mohamed Ali Ibrahim A.abd el-Moghith mohamed N.el-Derini Saad M.Darwish Higher Institute for Tourism Hotels and ComputerAl-SeyoufAlexandria21533Egypt Department of Information Technology Institute of Graduate Studies and ResearchAlexandria University21526Egypt Department of Computer and Systems Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt

Routing is a key function inWireless Sensor Networks(WSNs)since it facilitates data transfer to base *** attacks have the potential to destroy and degrade the functionality ofWSNs.A trustworthy routing system is essential for routing security andWSN *** methods have been implemented to build trust between routing nodes,including the use of cryptographic methods and centralized ***,the majority of routing techniques are unworkable in reality due to the difficulty of properly identifying untrusted routing node *** the moment,there is no effective way to avoid malicious node *** a consequence of these concerns,this paper proposes a trusted routing technique that combines blockchain infrastructure,deep neural networks,and Markov Decision Processes(MDPs)to improve the security and efficiency of WSN *** authenticate the transmission process,the suggested methodology makes use of a Proof of Authority(PoA)mechanism inside the blockchain *** validation group required for proofing is chosen using a deep learning approach that prioritizes each node’s *** are then utilized to determine the suitable next-hop as a forwarding node capable of securely transmitting *** to testing data,our routing system outperforms current routing algorithms in a 50%malicious node routing scenario.

关键词： Wireless sensor networks trusted routing deep neural network blockchain markov decision