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Experimental investigation of viscous oil-water-sand flow in horizontal pipes:Flow patterns and pressure gradient

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Petroleum 2024年第2期10卷 275-293页

作者： tarek Ganat Petroleum and Chemical Engineering Department Sultan Qaboos UniversityP.O.Box 50Muscat 123Sultanate of Oman

Fluid production from unconsolidated reservoirs often leads in sand production,which poses a number of *** deposition in flowlines can result in significant pressure dips,pipe and facility damage,and obstructions that decrease *** research is needed to understand the movement and deposition of sand in oil-water-sand(O-W-s) *** article focuses on O-W-s flows in a 6-meter-long horizontal pipe with an inner diameter of 0.0381 *** study looks at the flow behavior of high viscosity oil-water(O-W),water-sand(W-s),and oil-water-sand(O-W-s) *** were carried out at 250 psig pressure in a laboratory flow test facility using various heavy synthetic oils(viscosities ranging from 3500 cP to 7500 cP at 25℃) and tap *** sand concentration varied from 1% to 10%,with an average sand particle diameter of 145 μm and material density of 2630 kg/m~*** cuts ranged from 0.0 to *** experimental results revealed a minor change in pressure gradient between(O-W) and(O-W-s) ***,increasing the sand concentration in(O-W-s) flow resulted in higher pressure *** reduction factor of pressure gradient indicated that the highest decrease in pressure drop occurred at higher superficial oil ***,a direct relationship was observed between the reduction factor and the decrease in water *** results also showed that the minimum required transportation velocity for sand slurry decreased with increasing superficial oil velocity,while the minimum transportation condition increased with higher sand *** comparison between the expected pressure gradient from Bannwart and McKibben et *** the actual experimental data demonstrated significant accuracy for the oil viscosities and superficial oil velocities used in the study.

关键词： slurry velocity Flow pattern Pressure gradient High viscosity Minimum transport condition

synthesized graphene oxide and fumed aerosil 380 dispersion stability and characterization with partially hydrolyzed polyacrylamide

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Chinese Journal of Chemical Engineering 2021年第6期34卷 307-322页

作者： Najeebullah Lashari tarek Ganat Department of Petroleum Engineering Universiti Teknologi PETRONAS32610 Seri IskandarPerak Darul RidzuanMalaysia Department of Petroleum and Gas Engineering Dawood University of Engineering&TechnologyM.A Jinnah RoadKarachi 74800Pakistan

Hydrolyzed polyacrylamide(HPAM)is a commonly used polymer for the chemicals,mining and refining processes of hydrocarbon but suffers from a persistent high-temperature instability *** contrast,the nanoparticle suspension remains a technical challenge because of the strong interactions of van der Waal forces within nanoparticles,which always encourage *** research sought to improve nanoparticles(NP)stability and polymer(HPAM)rheological properties to improved hydrocarbon recovery by utilizing synthesized graphene oxide(GO)nanosheets and fumed Aerosil 380 silica oxide(siO_(2)).The aqueous nanocomposites based on HPAM-GO and HPAM-siO_(2) in aqueous polymeric solutions have been developed,and its viscoelastic and static behaviour is *** results imply that by adding fumed silica NP,the viscoelastic behaviour of HPAM is marginally improved,particularly in high temperatures and salinity,however,the inclusion of GO's significantly improves the viscosity and stability of the base polymer fluid at high *** Fourier data for the transformation of the infrared spectrum confirmed that the hydrogen bonding formed between HPAM carbonyl groups and silica NP surface silanol functionality and covalent interlinking of electrostatic h-bonding between HPAM and functional GO contributed to the improved stabilization and improved rheological performance that helps to recover high salinity and temperature hydrocarbons.

关键词： Aggregation Composites Chemical enhance oil recovery Hydrocarbons Nanoparticles Polymer

Face Templates Encryption Technique Based on Random Projection and Deep Learning

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Computer systems science & Engineering 2023年第3期44卷 2049-2063页

作者： Mayada tarek Department of Computer science Mansoura UniversityMansoura35516Egypt Department of Computer science Jouf UniversityJouf2014KSA

Cancellable biometrics is the solution for the trade-off between two concepts:Biometrics for security and security for *** cancelable template is stored in the authentication system’s database rather than the original biometric *** case of the database is compromised,it is easy for the template to be canceled and regenerated from the same biometric *** of the cancelable template comes from the diversity of the cancelable transformation parameters(cancelable key).Therefore,the cancelable key must be secret to be used in the system authentication process as a second authentication factor in con-junction with the biometric *** main contribution of this paper is to tackle the risks of stolen/lost/shared cancelable keys by using biometric trait(in different feature domains)as the only authentication factor,in addition to achieving good performance with high *** standard Generative Adversarial Network(GAN)is proposed as an encryption tool that needs the cancelable key during the training phase,and the testing phase depends only on the biometric ***,random projection transformation is employed to increase the proposed system’s security and *** proposed transformation system is tested using the standard ORL face database,and the experiments are done by applying different features ***,a security analysis for the proposed transformation system is presented.

关键词： Cancelable biometrics(CBs) random projection ORL face database generative adversarial network(GAN)

METHOD OF CENTERs ALGORITHM FORMULTI-OBJECTIVE PROGRAMMING PROBLEMs

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Acta Mathematica scientia 2009年第5期29卷 1128-1142页

作者： tarek Emam Department of Mathematics Faculty of Science (Suez) Suez Canal University Suez Egypt

In this paper, we consider a method of centers for solving multi-objective programming problems, where the objective functions involved are concave functions and the set of feasible points is convex. The algorithm is defined so that the sub-problems that must be solved during its execution may be solved by finite-step procedures. Conditions are given under which the algorithm generates sequences of feasible points and constraint multiplier vectors that have accumulation points satisfying the KKT conditions. Finally, we establish convergence of the proposed method of centers algorithm for solving multiobjective programming problems.

关键词： method of centers multi-objective convergence approximated efficient solution

Impact Assessment and Mitigation Techniques for High Penetration Levels of Renewable Energy sources in Distribution Networks:Voltage-control Perspective

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Journal of Modern Power systems and Clean Energy 2022年第2期10卷 450-458页

作者： Ahmed s.A.Awad Dave Turcotte tarek H.M.El-Fouly Natural Resources Canada Can-metENERGYVarennesCanadaon leave from the Electrical Power and Machines DepartmentFaculty of EngineeringAin Shams UniversityCairo 11566Egyp Natural Resources Canada CanmetENERGYVarennesCanada Advanced Power and Energy Center Khalifa UniversityAbu DhabiUnited Arab Emirates

The integration of renewable distributed generation(RDG)into distribution networks is promising and increasing ***,high penetration levels of distributed generation(DG)are often limited as they may have an adverse effect on the operation of distribution *** of the operation challenges is the interaction between DG and voltage-control equipment,e.g.,an under-load tap changer(ULTC),which is basically designed to compensate for voltage changes caused by slow load *** integration of variable DGs leads to rapid voltage fluctuations,which can negatively affect the tap operation of *** paper investigates the impact of high penetration levels of RDG on the tap operation of ULTC in distribution networks through *** mitigation techniques that can alleviate this impact are also *** these techniques,constant power-factor mode is regarded as the best trade-off between the simplicity and effectiveness of minimizing the number of tap *** are performed on a Canadian benchmark rural distribution feeder using OpenDss software.

关键词： Renewable energy distributed generation(DG) voltage regulator load tap changer distribution network.

YKL-40 expression in human hepatocellular carcinoma:a potential biomarker?

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Hepatobiliary & Pancreatic Diseases International 2011年第6期10卷 605-610页

作者： tarek Hassanein Liver Center Hillcrest Medical CenterUniversity of California at San DiegoCA 92103USA

BACKGROUND:YKL-40 is a new biomarker with diagnostic value in many different *** it may serve as a biomarker for hepatocellular carcinoma (HCC) is still *** study aimed to examine the expression of YKL-40 in the serum and liver tissues of HCC patients and in HCC cell lines,in comparison with that in non-HCC liver disease patients and non-tumor hepatic cell lines,***:Immunohistochemical staining was used to detect YKL-40 protein expression in liver biopsy specimens from 8 HCC *** was used to assess the serum YKL-40 level in 90 HCC patients,90 inactive HBsAg carrier (IHC) patients with normal liver functions,and 90 liver cirrhosis ***-time PCR was used to determine the YKL-40 mRNA expression in three HCC cell lines and two non-tumor hepatic cell ***:Immunohistochemical staining of liver biopsy specimens from HCC patients showed that the YKL-40 protein expression in tumor tissue was higher than that in adjacent normal *** revealed that the YKL-40 serum level in the HCC group was significantly higher than that in the IHC group,but not significantly different from that in the cirrhosis ***-time PCR showed that YKL-40 mRNA levels in HCC cell lines were significantly higher than those in nontumor hepatic ***:YKL-40 is highly expressed in HCC at the molecular,cellular and tissue ***,it may not serve as a serum biomarker for HCC because measurement of the serum YKL-40 level cannot distinguish HCC from cirrhosis.

关键词： YKL-40 hepatocellular carcinoma cirrhosis

Long-term changes in sea surface temperature(ssT)within the southern Levantine Basin

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Acta Oceanologica sinica 2021年第3期40卷 27-33页

作者： tarek M.El-Geziry Laboratory of Physical Oceanography Division of Marine EnvironmentNational Institute of Oceanography and Fisheries(NIOF)Alexandria21556Egypt

Knowledge of sea surface temperature(ssT)behaviour is vital for long-term climate *** study highlights essential outcomes about the distinguishable and unsurprising warming of the ssT along the southern border of the Levantine *** analysis is based on monthly ssT data for the period *** southern Levantine Basin has undergone ssT increase,during the last 71 *** this study,a consistent warming trend has been found for the analysed ssT data series,with a rate of 0.04℃/a,i.e.,0.4℃/(10 a).From 1975 to 1991 the mean annual ssT was 17.1℃,and this increased to be 19.2℃,over the period *** revealed two opposite trends of variability:a decreasing trend(−0.06℃/a)over the period 1975-1991,and an increasing trend(0.2℃/a)from 2002 to *** the period 1948-2018,positive mean annual ssT anomalies had an average of 1.8℃,and negative anomalies had an average of−1.1℃.The lowest ssT total increase was found from January to April,with values about 0.03℃,while the highest warming appeared from June to *** driving mechanisms behind the ssT changes need to be more investigated,to understand the future trends and impacts of climate change in the Levantine Basin.

关键词： Mediterranean sea Levantine Basin sea surface temperature anomaly trends warming

Investigative Review of Design Techniques of Parabolic Trough solar Collectors

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Frontiers in Heat and Mass Transfer 2024年第1期22卷 317-339页

作者： Roba tarek AbdelFatah Irene s.Fahim Mohamed Mahran Kasem smart Engineering systems Research Center(sEsC) Nile UniversityShaikh Zayed City12588Egypt

Parabolic trough solar collectors(PTCs)are among the most cost-efficient solar thermal *** have several applications,such as feed heaters,boilers,steam generators,and electricity generators.A PTC is a concentrated solar power system that uses parabolic reflectors to focus sunlight onto a tube filled with heattransfer *** performance can be investigated using optical and thermal mathematical *** models calculate the amount of energy entering the receiver,the amount of usable collected energy,and the amount of heat loss due to convection and *** are several methods and configurations that have been developed so far;however,it is usually difficult for a designer to choose the appropriate method or configuration for his *** present work investigates different PTC configurations and methods of solution,compares their efficiency and accuracy,summarizes their key behaviors and trends,and improves the available methods by maximizing the positives and minimizing the negatives among *** investigated three methods and seven *** findings suggest that optimizing the collector structure,tracking system,and reflector can lead to high PTC performance and reduced capital *** investigating and comparing the recent mathematical models,the study identified a clear deficiency in estimating the output *** PTC’s solution methods are investigated,and a novel method is developed to give more accurate estimations of the output temperature.

关键词： Parabolic trough collectors solar collector PTC mathematical models

The Heat Equation for the Dirichlet Fractional Laplacian with Negative Potentials:Existence and Blow-up of Nonnegative solutions

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Acta Mathematica sinica,English series 2017年第7期33卷 981-995页

作者： Ali BEN AMOR tarek KENZIZI Department of Mathematics Faculty of Sciences of GabèsUniversity GabèsGabès 6072Tunisia Department of Mathematics Faculty of Sciences of TunisUniversity Tunis EIManarTunis 1001Tunisia

We establish conditions ensuring either existence or blow-up of nonnegative solutions for the heat equation generated by the Dirichlet fractional Laplacian perturbed by negative potentials on bounded sets. The elabora... 详细信息

关键词： Fractional Laplacian heat equation Dirichlet form blow-up