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A machine learning framework for damage mechanism identification from acoustic emissions in unidirectional siC/siC composites

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npj Computational Materials 2021年第1期7卷 1326-1335页

作者： C.Muir B.swaminathan K.Fields a.s.almansour K.sevener C.smith M.Presby J.D.Kiser T.M.Pollock s.Daly Materials University of California-Santa BarbaraSanta BarbaraCAUSA Mechanical Engineering University of California-Santa BarbaraSanta BarbaraCAUSA NAsA Glenn Research Center ClevelandOHUSA Materials science and Engineering University of Michigan-Ann ArborAnn ArborMIUSA

In this work,we demonstrate that damage mechanism identification from acoustic emission(AE)signals generated in minicomposites with elastically similar constituents is *** waveforms were generated by siC/siC ceramic matrix minicomposites(CMCs)loaded under uniaxial tension and recorded by four sensors(two models with each model placed at two ends).signals were encoded with a modified partial power scheme and subsequently partitioned through spectral *** cracking and fiber failure were identified based on the frequency information contained in the AE event they produced,despite the similar constituent elastic properties of the matrix and ***,the resultant identification of AE events closely followed CMC damage chronology,wherein early matrix cracking is later followed by fiber breaks,even though the approach is fully domain-knowledge ***,the partitions were highly precise across both the model and location of the sensors,and the partitioning was *** presented approach is promising for CMCs and other composite systems with elastically similar constituents.

关键词： composites damage mechanism

Piezoelectric polarization and quantum size effects on the vertical transport in AlGaN/GaN resonant tunneling diodes

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Chinese Physics B 2016年第6期25卷 483-488页

作者： Dakhlaoui H almansour s Department of Physics College of Science for GirlsUniversity of Dammam (UOD)

In this work,the electronic properties of resonant tunneling diodes（RTDs） based on GaN-AlxGa（1-x）N double barriers are investigated by using the non-equilibrium Green functions formalism（NEG）.These materials each present a wide conduction band discontinuity and a strong internal piezoelectric field,which greatly affect the electronic transport *** electronic density,the transmission coefficient,and the current–voltage characteristics are computed with considering the spontaneous and piezoelectric *** influence of the quantum size on the transmission coefficient is analyzed by varying GaN quantum well thickness,AlxGa1-xN width,and the aluminum concentration *** results show that the transmission coefficient more strongly depends on the thickness of the quantum well than the barrier;it exhibits a series of resonant peaks and valleys as the quantum well width *** addition,it is found that the negative differential resistance（NDR） in the current–voltage（I–V） characteristic strongly depends on aluminum concentration *** is shown that the peak-to-valley ratio（PVR） increases with xAlvalue *** findings open the door for developing vertical transport nitrides-based IsB devices such as THz lasers and detectors.

关键词： nitride semiconductor resonant tunneling diode current density

Effect of si δ-Doping on the Linear and Nonlinear Optical Absorptions and Refractive Index Changes in InAlN/GaN single Quantum Wells

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Chinese Physics Letters 2016年第2期33卷 102-105页

作者： shaffa almansour Hassen Dakhlaoui Emane Algrafy Department of Physics College of Science for GirlsUniversity of Dammam

In the framework of effective mass approximation, we theoretically investigate the electronic structure of the si δ-doped InAIN/GaN single quantum well by solving numerically the coupled equations schrodinger-Poisson self-consistently. The linear, nonlinear optical absorption coefficients and relative refractive index changes are calculated as functions of the doping concentration and its thickness. The obtained results show that the position and the amplitude of the linear and total optical absorption coefficients and the refractive index changes can be modified by varying the doping concentration and its thickness. In addition, it is found that the maximum of the optical absorption can be red-shifted or blue-shifted by varying the doping concentration. The obtained results are important for the design of various electronic components such as high-power FETs and infrared photonic devices.

关键词： of is In GaN in Doping on the Linear and Nonlinear Optical Absorptions and Refractive Index Changes in InAlN/GaN single Quantum Wells on

Recovery of free volume in PIM-1 membranes through alcohol vapor treatment

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Frontiers of Chemical science and Engineering 2021年第4期15卷 872-881页

作者： Faiz almansour Monica Alberto Rupesh s.Bhavsar Xiaolei Fan Peter M.Budd Patricia Gorgojo Department of Chemical Engineering and Analytical science School of EngineeringThe University of ManchesterManchester M139PLUK Department of Chemistry School of Natural SciencesThe University of ManchesterManchester M139PLUK

Physical aging is currently a major obstacle for the commercialization of PIM-1 membranes for gas separation applications.A well-known approach to reversing physical aging effects of PIM-1 membranes at laboratory scale is soaking them in lower alcohols,such as methanol and ***,this procedure does not seem applicable at industrial level,and other strategies must be *** this work,a regeneration method with alcohol vapors(ethanol or methanol)was developed to recover permeability of aged PIM-1 membranes,in comparison with the conventional soaking-in-liquid *** gas permeability and separation performance,before and post the regeneration methods,were assessed using a binary mixture of CO_(2) and CH_(4)(1:1,v:v).Our results show that an 8-hour methanol vapor treatment was sufficient to recover the original gas permeability,reaching a CO_(2) permeability>7000 barrer.

关键词： polymer of intrinsic microporosity(PIM) PIM-1 physical aging gas separation vapor-phase regeneration

A Deep Learning Approach for Landmines Detection Based on Airborne Magnetometry Imaging and Edge Computing

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Computer Modeling in Engineering & sciences 2024年第5期139卷 2117-2137页

作者： Ahmed Barnawi Krishan Kumar Neeraj Kumar Bander Alzahrani Amal almansour Faculty of Computing and Information Technology King Abdulaziz UniversityJeddahSaudi Arabia Department of Computer science and Engineering Thapar Institute of Engineering and TechnologyDeemed to be UniversityPatialaIndia

Landmines continue to pose an ongoing threat in various regions around the world,with countless buried landmines affecting numerous human *** detonation of these landmines results in thousands of casualties reported worldwide ***,there is a pressing need to employ diverse landmine detection techniques for their *** effective approach for landmine detection is UAV(Unmanned Aerial Vehicle)based AirborneMagnetometry,which identifies magnetic anomalies in the local terrestrial magnetic *** can generate a contour plot or heat map that visually represents the magnetic field *** the effectiveness of this approach,landmine removal remains a challenging and resource-intensive task,fraughtwith *** computing,on the other hand,can play a crucial role in critical drone monitoring applications like landmine *** processing data locally on a nearby edge server,edge computing can reduce communication latency and bandwidth requirements,allowing real-time analysis of magnetic field *** enables faster decision-making and more efficient landmine detection,potentially saving lives and minimizing the risks involved in the ***,edge computing can provide enhanced security and privacy by keeping sensitive data close to the source,reducing the chances of data exposure during *** paper introduces the MAGnetometry Imaging based Classification system(MAGICs),a fully automated UAV-based system designed for landmine and buried object detection and *** have developed an efficient deep learning-based strategy for automatic image classification using magnetometry dataset *** simulating the proposal in various network scenarios,we have successfully detected landmine signatures present in themagnetometry *** trained models exhibit significant performance improvements,achieving a maximum mean average precision value of 97.8%.

关键词： CNN deep learning landmine detection magnetometer mean average precision UAV

Enabling Reachability Across Multiple Domains Without Controller synchronization in sDN

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Computers, Materials & Continua 2021年第10期69卷 945-965页

作者： Nauman Khan Rosli Bin salleh Ihsan Ali Zahid Khan Noman Mazhar Roobaea Alroobaea Fahad almansour Usman Ali Department of Computer system and Technology Faculty of Computer Science and Information TechnologyUniversity of MalayaMalaysia Department of Computer science and IT University of MalakandPakistan Robotics and Internet-of-Things Lab Prince Sultan UniversityRiyadhSaudi Arabia Department of Computer science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Computer science College of Sciences and Arts RassQassim UniversityBuraydah51452Saudi Arabia

software-defined networking(sDN)makes network agile and flexible due to its programmable *** extensive network has multiple domains in sDN for the scalability and performance of the ***,the inter-domain link is also crucial for the stability of the entire network on the data plane *** than one inter-domain connection enhances the scalability of the data plane ***,it faces a reachability problem with the principal root,which causes forwarding loops and packet drops in the network,thereby degrading network *** proposed solution is a multiple controller architecture;however,this approach increases the complexity and affects network ***,in this study,we propose a framework that avoids forwarding loops and packet drops without the synchronization of multiple-domain controllers in the network using an avoid loop with test packet ***,we collect the link status for improved routing and load balancing for the upcoming flow across inter-domain links to prevent congestion and increase throughput in real *** proposed methodology can significantly reduce the controller workload against multiple controller architecture,minimize flow setup latency,and improve throughput.

关键词： Multiple domain packet drop forwarding loop load balancing sDN multiple controller

A secondary bile acid from microbiota metabolism attenuates ileitis and bile acid reduction in subclinical necrotic enteritis in chickens

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Journal of Animal science and Biotechnology 2020年第3期11卷 767-776页

作者： Mohit Bansal Ying Fu Bilal Alrubaye Mussie Abraha Ayidh almansour Anamika Gupta Rohana Liyanage Hong Wang Billy Hargis Xiaolun sun Center of Excellence for Poultry science University of Arkansas1260 W Maple St.O409FayettevilleAR 72701USA CEMB University of ArkansasFayettevilleAR 72701USA Department of Chemistry University of ArkansasFayettevilleAR 72701USA.

Background:Clostridium perfringens-induced chicken necrotic enteritis(NE)is responsible for substantial economic losses worldwide ***,as a result of antibiotic growth promoter prohibition,the prevalence of NE in chickens has *** study was aimed to reduce NE through titrating dietary deoxycholic acid(DCA)as an effective antimicrobial *** and methods:Day-old broiler chicks were assigned to six groups and fed diets supplemented with 0(basal diet),0.8,1.0 and 1.5 g/kg(on top of basal diet)*** birds were challenged with Eimeria maxima(20,000 oocysts/bird)at d 18 and ***(109 CFU/bird per day)at d 23,24,and 25 to induce *** birds were sacrificed at d 26 when ileal tissue and digesta were collected for analyzing histopathology,mRNA accumulation and *** colonization by real-time PCR,targeted metabolomics of bile acids,fluorescence in situ hybridization(FIsH),or terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)***:At the cellular level,birds infected with *** and *** developed subclinical NE and showed shortening villi,crypt hyperplasia and immune cell infiltration in *** DCA alleviated the NE-induced ileal inflammation in a dose-dependent manner compared to NE control *** with the increased histopathological scores,subclinical NE birds suffered body weight gain reduction compared to the uninfected birds,an effect attenuated with increased doses of dietary *** the molecular level,the highest dose of DCA at 1.5 g/kg reduced *** luminal colonization compared to NE birds using PCR and ***,the dietary DCA reduced subclinical NE-induced intestinal inflammatory gene expression and cell apoptosis using PCR and TUNEL *** further examining ileal bile acid pool through targeted metabolomics,subclinical NE reduced the total bile acid level in ileal digesta compared to uninfected ***,dietary DCA increased total

关键词： Bile acid Chicken Clostridium perfringens Deoxycholic acid Intestinal inflammation Necrotic enteritis

The Endonasal Endoscopic Management of Paranasal sinuses Mucoceles

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International Journal of Otolaryngology and Head & Neck surgery 2021年第1期10卷 20-29页

作者： sarah A. almansour Ali A. AlMomen Otorhinolaryngology Head and Neck surgery Resident King Fahad Specialist Hospital Dammam KSA senior Consultant Rhinology and skull Base surgeon King Fahad Specialist Hospital Dammam KSA

Introduction: Paranasal sinuses mucoceles are benign, epithelial lined, mucus filled lesions, causing destruction of the adjacent sinus walls, and with further gradual extension to adjacent structures, serious morbidi... 详细信息

strong>Introduction:strong> Paranasal sinuses mucoceles are benign, epithelial lined, mucus filled lesions, causing destruction of the adjacent sinus walls, and with further gradual extension to adjacent structures, serious morbidities and mortalities may occur. strong>Objective:strong> To emphasize on the efficacy of endonasal endoscopic marsupialization in the treatment of paranasal sinus mucoceles. strong>Method:strong> Retrospective descriptive study on paranasal sinus mucocele cases operated on endoscopically by the author (AAM), in the 10-year-period from to 2009-2019. strong>Result:strong> Total of 23 cases were included, 16 were males and 7 females, age ranging between 14 - 76 years, with a mean age of 45 years Location of mucoceles varied between: Frontal 7 cases (30%), Fronto-ethmoidal 6 cases (26%), Isolated Ethmoidal accounted for 3 cases (13%), sphenoidal 4 cases (17%), maxillary were 3 cases (13%) all of the 23 cases underwent endonasal endoscopic complete marsupialization, none of them required combination with external approach in-spite of different locations and complications, with no recurrence in a mean follow up period of 2.4 years. strong>Conclusion:strong> Endonasal endoscopic approach is a safe, efficient approach in the treatment of most paranasal sinus mucocele case in their different presentations and locations.

关键词： Mucocele Paranasal sinus Chronic Rhinosinusitis Endoscopic sinus surgery Marsupialization

Theoretical study of Electronic Transmission in Resonant Tunneling Diodes Based on GaAs/AlGaAs Double Barriers under Bias Voltage

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Optics and Photonics Journal 2014年第3期4卷 39-45页

作者： shaffa Abdullah almansour Dakhlaoui Hassen Department of Physics College of Science for Girls Dammam Saudi Arabia

In this paper, we theoretically study the quantum size effects on the electronic transmission and current density of the electrons in GaAs/AlGaAs resonant tunneling diodes by solving the coupled equations schrodinger-Poisson self-consistently. It is found that the resonant peaks of the trans-mission coefficients shift towards the lower energy regions as the applied bias voltage increases. Our results indicate that the transmission coefficient depends strongly on the variation of the thickness of collector and emitter. We also study the effect of the doping concentration located in the emitter and collector regions on the transmission and current density. We found that the dop-ing concentration can greatly affect the transmission coefficient and the current density;in partic-ular it increases the peak of the current density and displaces the position of the maxima of the current dependence on the applied bias voltage.

关键词： GaAs semiconductor Resonant Tunneling Diode Current-Density