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Frontiers of Structural and Civil Engineering 2021年第3期15卷 643-651页

作者： Farnaz BATOOL Muhammad saad KHAN Vivek BINDIGANAVILE Department of Civil Engineering NED University of Engineering&TechnologyKarachi75270Pakistan Department of Civil and Environmental Engineering University of AlbertaEdmontonT6G2R3Canada

This study presents the results of the 3D microstructure,thermal conductivity,and heat flow in cement-based foams and examines their changes with a range of *** were captured using X-ray micro computed tomography(micro-CT)imaging technique on cement-based foam samples prepared with densities of 400,600,and 800 kg/m^(3).These images were later simulated and quantified using 3D data visualization and analysis *** on the analysis,the pore volume of 11000µm^(3)was determined across the three densities,leading to optimal ***,distinct pore diameters of 15µm for 800 kg/m^(3),and 20µm for 600 and 400 kg/m^(3)were found to be *** of the pores were spherical,with only 10%appearing elongated or *** addition,a difference of 15%was observed between the 2D and 3D porosity ***,a difference of 5%was noticed between the experimentally measured thermal conductivity and the numerically predicted value and this variation was constant across the three cast *** 3D model showed that heat flows through the cement paste solids and with an increase in porosity this flow reduces.

关键词： 3D pore volume distribution X-ray tomography 3D shape factor heat flow

Epileptic Seizures Diagnosis Using Amalgamated Extremely Focused EEG Signals and Brain MRI

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Computers, Materials & Continua 2023年第1期74卷 623-639页

作者： Farah Mohammad saad Al-Ahmadi Department of Computer Science King Saud UniversityRiyadh11543Saudi Arabia

There exists various neurological disorder based diseases like tumor,sleep disorder,headache,dementia and *** these,epilepsy is the most common neurological illness in humans,comparable to *** is a severe chronic neurological illness that can be discovered through analysis of the signals generated by brain neurons and brain Magnetic resonance imaging(MRI).Neurons are intricately coupled in order to communicate and generate signals from human *** to the complex nature of electroencephalogram(EEG)signals and MRI’s the epileptic seizures detection and brain related problems diagnosis becomes a challenging *** based techniques and machine learning models are continuously giving their contributions to diagnose all such diseases in a better way than the normal process of *** performancemay sometime degrade due to missing information,selection of poor classification model and unavailability of quality data that are used to train the models for better *** research work is an attempt to epileptic seizures detection by using amulti focus dataset based on EEG signals and *** key steps of this work are:feature extraction having two different streams i.e.,EEGusingwavelet transformation along with SVD-Entropy,and MRI using convolutional neural network(CNN),after extracting features fromboth streams,feature fusion is applied to generate feature vector used by support vector machine(SVM)to diagnose the epileptic *** the experimental evaluation and results comparison with the current state-of-the-art techniques,it has been concluded that the performance of the proposed scheme is better than the existing models.

关键词： Epilepsy EEG MRI CNN SVM

Sensitivity-based upscaling for history matching of reservoir models

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Petroleum Science 2016年第3期13卷 517-531页

作者： saad Mehmood Abeeb A.Awotunde United Energy Pakistan Bahria Complex-l M.T. Khan Road Karachi 74000 Sindh Pakistan Department of Petroleum Engineering King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

Simulation of reservoir flow processes at the finest scale is computationally expensive and in some cases ***,upscaling of several fine-scale grid blocks into fewer coarse-scale grids has become an integral part of reservoir simulation for most *** is because as the number of grid blocks increases,the number of flow equations increases and this increases,in large proportion,the time required for solving flow *** we can adopt parallel computation to share the load,a large number of grid blocks still pose significant computational ***,upscaling acts as a bridge between the reservoir scale and the simulation *** as the upscaling ratio is increased,the accuracy of the numerical simulation is reduced;hence,there is a need to keep a balance between the *** this work,we present a sensitivity-based upscaling technique that is applicable during history *** method involves partial homogenization of the reservoir model based on the model reduction pattern obtained from analysis of the sensitivity *** technique is based on wavelet transformation and reduction of the data and model spaces as presented in the 2Dwp-wk *** the 2Dwp-wk approach,a set of wavelets of measured data is first selected and then a reduced model space composed of important wavelets is gradually built during the first few iterations of nonlinear *** building of the reduced model space is done by thresholding the full wavelet sensitivity *** pattern of permeability distribution in the reservoir resulting from the thresholding of the full wavelet sensitivity matrix is used to determine the neighboring grids that are *** essence,neighboring grid blocks having the same permeability values due to model space reduction are combined into a single grid block in the simulation model,thus integrating upscaling with wavelet multiscale inverse *** apply the method to estimate the parameters

关键词： Upscaling Inverse analysis History matching Sensitivity Wavelets

Assessment of Urban Sprawl on Agricultural Soil of Northern Nile Delta of Egypt Using RS and GIS

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Chinese Geographical Science 2015年第3期25卷 274-282页

作者： Adel SHALABY Farahat saad MOGHANM National Authority for Remote Sensing and Space Sciences Soil and Water Science Department-faculty of Agricultural-Kafrelsheikh University

Urban sprawl is threatening the limited highly fertile land in the Nile delta of Egypt. Landsat TM satellite images of 1984, 1992 and ETM+ of 2006 have been used to study the impact of urban sprawl on agricultural land of the Northern Nile delta, Egypt. Visual interpretation using on screen digitizing and change detection techniques were applied for monitoring the urban sprawl. Combining the land capability map and the urban thematic layer using GIS made it possible to point out the risk of urban expansion on the expense of the highly capable soil class. The results show that a total expansion of urban area amounted to 689.20 km2(6.3% of total area) during the study period 1984–2006. The urban expansion during the 1984–2006 was on the expense of the most fertile soils where, the high capable soils(Class I) lost 247.14 km2(2.26 % of total area) and the moderate capable soils lost 32.73 km2(0.3% of total area), while the low capable soils lost only 57.39 km2(0.53% of total area). The urban encroachment over the non capable soils was very limited during the study period 1984–1992, where 7.33 km2 only was lost. The pattern of urban sprawl has been changed during the 1992 to 2006 whereas much larger area(50.64 km2) of the non capable soils was converted to urban. It can be concluded that the urban sprawl is one of the dominant degradation process on the land of Nile Delta.

关键词： urbanization remote sensing GIS land cover changes land use policy Nile Delta of Egypt

Evolution of care in cirrhosis: Preventing hepatic decompensation through pharmacotherapy

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World Journal of Gastroenterology 2023年第1期29卷 61-74页

作者： Seohyuk Lee saad Saffo Department of Medicine Section of Digestive DiseasesYale School of MedicineNew HavenCT 06520-8019United States

Cirrhosis is a leading cause of morbidity and mortality,impacting more than 120 million people *** geographic differences exist,etiologic factors such as alcohol use disorder,chronic viral hepatitis infections,and non-alcoholic fatty liver disease are prevalent in nearly every ***,significant effort has been devoted to modifying these risks to prevent disease ***,more than 11%of patients with compensated cirrhosis experience hepatic decompensation each *** transition signifies the most important prognostic factor in the natural history of the disease,corresponding to a decline in median survival to below 2 *** the past decade,the need for pharmacotherapies aimed at reducing the risk for hepatic decompensation has been emphasized,and non-selective beta-blockers have emerged as the most effective option to ***,a critical therapeutic gap still exists,and additional therapies have been proposed,including statins,rifaximin,and sodium-glucose cotransporter-2 *** on the results of innovative retrospective analyses and small-scale prospective trials,these pharmacotherapies represent promising options,but further studies,including randomized controlled trials,are necessary before they can be incorporated into clinical *** report highlights the potential impact of these agents and others in preventing hepatic decompensation and discusses how this paradigm shift may pave the way for guideline-directed medical therapy in cirrhosis.

关键词： Cirrhosis Hepatic decompensation Beta-blockers Statins Sodium-glucose cotransporter-2 inhibitors Rifaximin

Improved Semi-empirical Model of Proton Exchange Membrane Fuel Cell Incorporating Fault Diagnostic Feature

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1566-1573页

作者： saad Saleem Khan Hussain Shareef Ahmad Asrul Ibrahim Department of Electrical Engineering College of EngineeringUnited Arab Emirates University IEEE Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia

The membrane water content of the proton exchange membrane fuel cell(PEMFC)is the most important feature required for water management of the PEMFC *** improper management of water in the fuel cell may lead to system *** various faults,flooding and drying faults are the most frequent in the PEMFC *** paper presents a new dynamic semi-empirical model which requires only the load current and temperature of the PEMFC system as the input while providing output voltage and membrane water content as its major *** other PEMFC systems,the proposed dynamic model calculates the internal partial pressure of oxygen and hydrogen rather than using special internal ***,the membrane water content and internal resistances of PEMFC are modelled by incorporating the load current condition and temperature of the PEMFC *** model parameters have been extracted by using a quantum lightening search algorithm as an optimization technique,and the performance is validated with experimental data obtained from the NEXA 1.2 k W PEMFC *** further demonstrate the capability of the model in fault detection,the variation in membrane water content has been studied via the *** proposed model could be efficiently used in prognostic and diagnosis systems of PEMFC fault.

关键词： Proton exchange membrane fuel cell(PEMFC)fault membrane water content modelling optimization quan-tum lightening search algorithm

Hydrogen Detection With FBG Sensor Technology for Disaster Prevention

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Photonic Sensors 2013年第3期3卷 214-223页

作者： Said saad Lotfi HASSINE Group of Electronics and Quantum Physics Laboratory of Advanced Materials and Quantum Phenomena Faculty of Sciences of Tunis 2092 Tunisia National Institute of Applied Sciences and Technology University of Carthage North Urban Center of Tunis-B.P.676 Cedex Tunis-1080 Tunisia

Three fiber Bragg grating （FBG） sensors systems for hydrogen detection are presented using the classic Pd （palladium） coating technique （500nm） as the hydrogen sensitive film and titanium （Ti） as the adhesive layer with the etched cladding. These systems are compared and used for disaster environment prevention in hydrogen leakage environment where higher values than the normal are presented which increase the risk of explosion. With these systems, 0. 1% - 4% of the hydrogen volume concentration range in the volume ratio was detected and monitored experimentally in the test room with the very sensitive and stable value which reached 60pm/1% HE. In addition, a fast response time, about 6 s, was obtained with an advanced sensor.

关键词： Fiber Bragg gratin (FBG) hydrogen detection sensor disaster environment prevention Pd coating technique

Classified VPN Network Traffic Flow Using Time Related to Artificial Neural Network

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Computers, Materials & Continua 2024年第7期80卷 819-841页

作者： saad Abdalla Agaili Mohamed Sefer Kurnaz Department of Electrical and Computer Engineering Altinbas UniversityIstanbul34000Turkey

VPNs are vital for safeguarding communication routes in the continually changing cybersecurity ***,increasing network attack complexity and variety require increasingly advanced algorithms to recognize and categorizeVPNnetwork *** present a novelVPNnetwork traffic flowclassificationmethod utilizing Artificial Neural Networks(ANN).This paper aims to provide a reliable system that can identify a virtual private network(VPN)traffic fromintrusion attempts,data exfiltration,and denial-of-service *** compile a broad dataset of labeled VPN traffic flows from various apps and usage ***,we create an ANN architecture that can handle encrypted communication and distinguish benign from dangerous *** effectively process and categorize encrypted packets,the neural network model has input,hidden,and output *** use advanced feature extraction approaches to improve the ANN’s classification accuracy by leveraging network traffic’s statistical and behavioral *** also use cutting-edge optimizationmethods to optimize network characteristics and *** suggested ANN-based categorization method is extensively tested and *** show the model effectively classifies VPN traffic *** also show that our ANN-based technique outperforms other approaches in precision,recall,and F1-score with 98.79%*** study improves VPN security and protects against new *** VPNtraffic flows effectively helps enterprises protect sensitive data,maintain network integrity,and respond quickly to security *** study advances network security and lays the groundwork for ANN-based cybersecurity solutions.

关键词： VPN network traffic flow ANN classification intrusion detection data exfiltration encrypted traffic feature extraction network security

Oilfield produced water treatment in internal-loop airlift reactor using electrocoagulation/flotation technique

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Chinese Journal of Chemical Engineering 2018年第4期26卷 879-885页

作者： saad H.Ammar Ahmed S.Akbar Department of Chemical engineering AL-Nahrain University

Oilfield produced water is large quantities of salty water trapped in underground formations and subsisted under high temperatures and pressures that are brought to the surface along with oil during production. Produced water(PW) contains a lot of pollutants such as hydrocarbons and metals, this water must be treated before disposal. Therefore, different techniques are being used to treat produced water. Electrocoagulation is an efficient treatment technique involving the dissolution of anodes and formation of electro-coagulants, while the simultaneous generation of H_2 bubbles at the cathode leads to the pollutant removal by flotation. Electrocoagulation(EC)method is one of the most promising and widely used processes to treat oilfield produced water. In the present work, a conventional internal-loop(draught tube) airlift reactor was utilized as electrocoagulation/flotation cell for PW treatment by inserting two aluminum electrodes in the riser section of the airlift reactor. The EC airlift reactor was operated in a batch mode for the liquid phase. Different experimental parameters were studied on the oil and turbidity removal efficiencies such as current density, initial pH, electrocoagulation time, and air *** experimental results showed that mixing of the oil droplets in the PW was accomplished using only the liquid recirculation resulted by H_2 microbubbles generated by EC process which enhanced the oil removal. The experimental results further showed that the EC time required achieving ≥ 90% oil removal efficiency decreases from 46 to 15 min when operating current density increases from 6.8 to 45.5 mA·cm^(-2). This reactor type was found to be highly efficient and less energy consuming compared to conventional existing electrochemical cells which used mechanical agitation.

关键词： Produced water Wastewater treatment Electrocoagulation/flotation Internal loop Airlift reactor

Geotectonic significance of the Neoproterozoic ophiolitic metagabbros of Muiswirab area,South Eastern Desert,Egypt:constraints from their mineralogical and geochemical characteristics

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Acta Geochimica 2020年第6期39卷 887-910页

作者： Moustafa M.Mogahed Wlaa Mahmoud saad Geology Department Faculty of ScienceBenha University-EgyptP.O.Box 13518BenhaEgypt

Petrological and geochemical studies of Neo-proterozoic metagabbros were carried out in the Muiswirab area,South Eastern Desert of *** Muiswirab area comprises of ophiolitic metagabbroic rocks(MOM),which are tectonically thrusted over a thick pile of metavolcanic rocks and intruded by syn-and post-tectonic granitoid *** whole-rock geochemical variations coupled with chemical compositions of mineral constituents are used to attain the genesis and tectonic evolution of the studied *** geothermobarometric investiga-tion of the analyzed amphiboles from(MOM)revealed that these metagabbros underwent regional metamorphism under lower to upper greenschist facies(biotite zone)conditions(at a temperature of 450 to 500℃and pressure of 1-3 kbar).Geochemically,the metagabbros(MOM)show tholeiitic affinity and cxhibiting both arc-and MORB-like characters as evidenced by their clinopyrox-ene compositions and the Ti/V ratios(11.84-31.65),which considered as prominent features of forearc tectonic *** geochemical features suggest a probable fractionation of olivine±clinopyroxene±plagioclase as well as insignificant crustal *** parental magma of the investigated MOM rocks seems to be developed in a sub-arc mantle wedge setting due to the enrichments of LILE(e.g..Rb,Ba,Sr,Pb)over HFSE(e.g,Ti,Nb,Y,Zr,Hf,Ta).The studied MOM rocks have lower values of Nb/U relative to MORB and OIB indicating that their geochemical variation produced due to the enrichment of a lithosphere mantle by OIB like *** ratios of Zn/Fet,La/Sm,Sm/Yb,Th/Yb and Nb/Yb indicate that the MOM rocks represent a fragment of oceanic crust originated at a supra-subduction zone environment and their parental magma developed by 5-30%partial melting of a spinel lherzolite mantle rather than pyroxenite in an island arc setting and conformable with most of the Egyptian ophiolitic metagabbros.

关键词： Egypt Eastern Desert Muiswirab area Ophiolitic metagabbros N-MORB Arc tholeiites Foreare tectonic regime Volcanic-arc setting