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Enhancing optical absorption in visible light of ZnO co-doped with europium and promethium by first-principles study through modified Becke and Johnson potential scheme

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Journal of Rare Earths 2019年第4期37卷 416-421页

作者： A.G.el Hachimi M.L.Ould NE A.el Yousfi A.Benyoussef A.el Kenz Laboratory of Condensed Matter and Interdisciplinary Sciences (LaMCScI) Associé Au CNRST (URAC 12) Département de Physique B.P.1014 Faculté des SciencesUniversité Mohammed V Hassan Ⅱ Academy of Science and Technology

By using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and Pm. In this calculation, we used Wien2 k code based on full potential linearized augmented plane waves(FP-LAPW) method with the modified Becke-Johnson(mBJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and Pm codoping leads to an increase in the band gap. electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications.

关键词： Zinc oxide Rare earth Density functional theory Modified Becke-Johnson Magnetic properties Spintronics

A broker-based semantic agent for discovering Semantic Web services through process similarity matching and equivalence considering quality of service

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Science China(Information Sciences) 2013年第1期56卷 18-41页

作者： elK Duygu el Atilla Computer Engineering Department Istanbul Aydin University electrical-elecronics Engineering Department Aksaray University

The lack of semantic descriptions for "web service properties" makes it difficult to find suitable web *** solutions are mostly based on broker/mediator agent ***,these techniques are syntactical,rather than semantics *** article presents a semantic matching approach for discovering Semantic Web services through a broker-based semantic agent(BSA).The BSA includes knowledge-bases and several processing *** BSA’s knowledge-bases are concept,task,and process ontologies built to describe both functional and non-functional parameters of *** BSA executes semantic-based matching algorithms to discover similar services through the semantic matching step,process equivalence task,and matching of quality of service *** services are ranked by client preferences utilizing the semantic descriptions of available *** matchmaker studies are reviewed and compared with the *** of the BSA algorithm is compared with SAM using published data and an experimental *** results indicate that our approach is better and more effective in some respects.

关键词： Semantic Web Semantic Web services broker web applications ontologies semantic agents

Wheat breeding for Hessian fly resistance at ICARDA

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The Crop Journal 2022年第6期10卷 1528-1535页

作者： Wuletaw Tadesse Samira el-Hanafi Karim el-Fakhouri Imane Imseg Fatima Ezzahra Rachdad Zakaria el-Gataa Mustapha el Bouhssini International Center for Agricultural Research in the Dry Areas(ICARDA) P.O.Box 6299RabatMorocco Biodiversity and Plant Sciences Program AbroBioSciencesMohammed VI Polytechnic UniversityLot 660-Hay Moulay Rachid43150 Ben GuerirMorocco

Hessian fly(HF),Mayetiola destructor(Say)is an important pest of wheat in North Africa,North America,Southern Europe,Northern Kazakhstan,Northwestern China,and New *** can cause up to 30%yield losses and sometimes can result in complete crop failure if infestation coincides with young stage of the wheat *** to-date have shown the availability of genetic diversity in the wheat genetic resources(landraces,wild relatives,cultivars,etc.)for resistance to Hessian *** 37 resistance genes have been reported from these wheat genetic resources for resistance to Hessian fly,of which,some have been deployed singly or in combination in the breeding programs to develop high yielding varieties with resistance to *** of resistant varieties in different agro-ecologies with other integrated management measures plays key role for the control of *** paper summarizes the importance,life cycle,mechanisms of resistance,gene mining,and wheat breeding efforts for HF resistance.

关键词： Breeding Gene introgression Hessian fly Resistance

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

Finite-Time and Fixed-Time Synchronization of Inertial Neural Networks with Mixed Delays

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Journal of Systems Science & Complexity 2021年第1期34卷 206-235页

作者： CHAOUKI Aouiti el ABED Assali University of Carthage Faculty of Sciences of BizertaDepartment of MathematicsResearch Units of Mathematics and Applications UR13ES477021 ZarzounaBizertaTunisia

This paper considers the drive-response synchronization in finite-time and fixed-time of inertial neural networks with time-varying and distributed delays(mixed delays). First, by constructing a proper variable substitution, the original inertial neural networks can be rewritten as a first-order differential system. Second, by constructing Lyapunov functions and using differential inequalities,some new and effective criteria are obtained for ensuring the finite-time synchronization. Finally, three numerical examples are also given at the end of this paper to show the effectiveness of the results.

关键词： Finite-time synchronization fixed-time synchronization inertial neural networks infinitetime distributed delays time-varying delays

Cylindrical Three-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Theoretical Physics 2018年第9期69卷 325-330页

作者： S.K.el-Labany E.K.el-Shewy H.N.Abd el-Razek A.A.el-Rahman Theoretical Physics Group Faculty of Science Domietta University Department of Physics Taibah University Theoretical Physics Group Faculty of Science Mansoura University Department of Physics Faculty of Science Assiut University

Wave properties of solitons in an unmagnetized four-component dusty plasma system contains isothermal distributed electrons, mobile ions, and negative-positive dusty grains have been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, the three dimension Kadomtsev-Petviashvili equation in cylindrical coordinates is obtained. The effects of dust grain charge on soliton pulse structures are studied. More specifically, solitary profile depending on the axial,radial, and polar angle coordinates with time is discussed. This investigation may be viable in plasmas of the Earth’s mesosphere.

关键词： dust plasmas 3D-CKP equation dusty-ion acoustic solitary waves isothermal electrons

Wear properties of copper and copper composites powders consolidated by high-pressure torsion

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Friction 2020年第2期8卷 433-450页

作者： Mohamed Ibrahim Abd el AAL Mechanical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addawaser 11991Saudi Arabia Mechanical Design&Production Department Faculty of EngineeringZagazig UniversityZagazig 44519Egypt

The wear characteristics of Cu and Cu-SiC composite microsize powders consolidated by cold compaction combined with sintering or high-pressure torsion(HPT)were *** HPT processed(HPTed)samples with bimodal and trimodal microstructures and fine Cu grains and SiC particle sizes have superior hardness,reasonable ductility level,and high wear *** wear mass loss and coefficient of friction of HPTed samples were remarkably lower than that of cold-compacted and sintered samples as well as that of micro and nano Cu and Cu-SiC composites from previous *** sample fabrication method has an apparent influence on the wear *** wear mechanism was converted from adhesive,delamination,three-body mechanism,grooves(take off the SiC particles),and cracks into abrasive wear after *** can be considered a dominant wear mechanism in all *** worn surface morphology and analysis support the relationship between wear mechanism and characteristics.

关键词： Cu-SiC composite powders high-pressure torsion(HPT) fine and coarse grains wear characteristics worn surface morphology

A Robust Tuned Random Forest Classifier Using Randomized Grid Search to Predict Coronary Artery Diseases

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Computers, Materials & Continua 2023年第5期75卷 4633-4648页

作者： Sameh Abd el-Ghany A.A.Abd el-Aziz Department of Information Systems College of Computer and Information SciencesJouf UniversityKSA Department of Information Systems Faculty of Computers and InformationMansoura UniversityEgypt Department of Information Systems and Technology Faculty of Graduate Studies for Statistical ResearchCairo UniversityEgypt

Coronary artery disease(CAD)is one of themost authentic cardiovascular afflictions because it is an uncommonly overwhelming heart *** breakdown of coronary cardiovascular disease is one of the principal sources of death all over *** deterioration is a challenge,especially in youthful and rural countries where there is an absence of humantrained *** heart diseases happen without apparent signs,high-level detection is *** paper proposed a robust and tuned random forest model using the randomized grid search technique to *** proposed framework increases the ability of CADpredictions by tracking down risk pointers and learning the confusing joint efforts between ***,the healthcare industry has a lot of data but needs to gain more *** proposed framework is used for extracting knowledge from data stores and using that knowledge to help doctors accurately and effectively diagnose heart disease(HD).We evaluated the proposed framework over two public databases,Cleveland and Framingham *** datasets were preprocessed by using a cleaning technique,a normalization technique,and an outlier detection ***,the principal component analysis(PCA)algorithm was utilized to lessen the feature dimensionality of the two ***,we used a hyperparameter tuning technique,randomized grid search,to tune a random forest(RF)machine learning(ML)*** randomized grid search selected the best parameters and got the ideal CAD *** proposed framework was evaluated and compared with traditional *** proposed framework’s accuracy,sensitivity,precision,specificity,and f1-score were 100%.The evaluation of the proposed framework showed that it is an unrivaled perceptive outcome with tuning as opposed to other ongoing existing frameworks.

关键词： Coronary artery disease tuned random forest randomized grid search classifier

LEO satellite clock analysis and prediction for positioning applications

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Geo-Spatial Information Science 2022年第1期25卷 14-33页

作者： Kan Wang Ahmed el-Mowafy School of Earth and Planetary Sciences Curtin UniversityPerthAustralia

The positioning service aided by low Earth orbit(LEO)mega-constellations has become a hot topic in recent *** achieve precise positioning,accuracy of the LEO clocks is important for single-receiver *** bridge the gap between the applicable time of the clock products and the time of positioning,the precise LEO clocks need to be predicted over a certain period depending on the sampling interval of the clock *** study discusses the prediction errors for periods from 10 s to 1 h for two typical LEO clock types,*** ultra-stable oscillator(USO)and the oven-controlled crystal oscillator(OCXO).The prediction is based on GNSS-determined precise clock estimates,where the clock stability is related to the GNSS estimation errors,the behaviors of the oscillators themselves,the systematic effects related to the environment and the relativistic effects,and the stability of the time *** on real data analysis,LEO clocks of the two different types are simulated under different conditions,and a prediction model considering the systematic effects is *** to a simple polynomial fitting model usually applied,the proposed model can significantly reduce the prediction errors,*** about 40%-70%in simulations and about 5%-30%for real data containing different miss-modeled *** both clock types,short-term prediction of 1 min would result in a root mean square error(RMSE)of a few centimeters when using a very stable time *** RMSE amounts to about 0.1 m,when a typical real-time time reference of the national center for space studies(CNES)real-time clocks was *** long-term prediction of 1 h,the RMSE could range from below 1 m to a few meters for the USOs,depending on the complexity of the miss-modeled *** OCXOs,the 1 h prediction could lead to larger errors with an RMSE of about 10 m.

关键词： LEO clock prediction USO OCXO relativistic effects