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Journal of Ocean Engineering and Science 2021年第3期6卷 276-284页

作者： P.Borah m.hassan Department of mathematics North Eastern Regional Institute of Science and TechnologyItanagarArunachal Pradesh 791109India

We consider a device which consists of a floating structure over a cylindrical plate placed at a finite height from the impermeable ocean *** paper developes the interaction of linear water waves with such a *** whole fluid domain is divided into a number of sub-domains and boundary value problems are formulated for each identified *** channel multipoles,separation of variables and matched eigenfunction expansion methods allow us to solve boundary value problems for the diffracted velocity potentials in each *** investigate the wave forces exerted on the proposed ***,the effects of the various parameters,e.g.,drafts,radii,the gap between the cylinders and mainly channel width of the device on the wave forces exerted by the cylinders are presented *** observe a small oscillation nature near the peak value of the exciting force for the particular value of channel width w=*** peak value of the exciting forces occurs near the wavenumber kr 1=1.0 for different width of the channel *** obtained results are compared with some available results,and it shows a good agreement between the obtained and available results.

关键词： Water waves Exciting force Channel multipoles Channel width Wavenumber,2000 mSC 76B07 76B15.

Liquation cracking in the heat-affected zone of IN939 superalloy tungsten inert gas weldments

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International Journal of minerals,metallurgy and materials 2020年第6期27卷 764-773页

作者： hassan Kazempour-Liasi mohammad Tajally hassan Abdollah-Pour Faculty of materials and metallurgical Engineering Semnan UniversitySemnanIran

The main aim of this study was to investigate liquation cracking in the heat-affected zone(HAZ)of the IN939 superalloy upon tungsten inert gas welding.A solid solution and age-hardenable filler metals were further *** the pre-weld heat-treated samples,upon solving the secondaryγ′particles in the matrix,primaryγ′particles in the base metal grew to"ogdoadically diced cubes"of about 2μm in side *** pre-weld heat treatment reduced the hardness of the base metal to about HV *** studies using optical and fieldemission scanning electron microscopy revealed that the IN939 alloy was susceptible to liquation cracking in the *** constitutional melting of the secondary,eutectic,and Zr-rich phases promoted the liquation cracking in the *** microstructure of the weld fusion zones showed the presence of fine spheroidalγ′particles with sizes of about 0.2μm after the post-weld heat treatment,which increased the hardness of the weld pools to about HV 350 and 380 for the Hastelloy X and IN718 filler metals,*** of a suitable solid solution filler metal could partially reduce the liquation cracking in the HAZ of IN939 alloy.

关键词： superalloy tungsten inert gas weld heat-affected zone liquation cracking

Tight Rock Wettability and Its Relationship to Other Petrophysical Properties： A montney Case Study

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Journal of Earth Science 2017年第2期28卷 381-390页

作者： Ali Javaheri hassan Dehghanpour James m.Wood University of Alberta Edmonton AB T6G 2R3 Canada Encana Corporation Calgary AB T2P 2S5 Canada

Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core plugs drilled from the cores of a well drilled in the montney Formation, an unconventional oil and gas play in the Western Canadian Sedimentary Basin. We characterize the samples by measuring the mineralogy using XRD（x-ray diffraction）, total organic carbon content, porosity, and permeability. Interestingly, the equilibrated water uptake of the five samples is similar, while, their oil uptake increases by increasing the core porosity and permeability. We define two wettability indices for the oil phase based on the slope and equilibrium values of water and oil imbibition curves. Both indices increase by increasing porosity and permeability, with the slope affinity index showing a stronger correlation. This observation suggests that part of the pore network has a stronger affinity to oil than to water. We also observe that the two indices decrease by increasing neutron porosity and gamma ray parameters measured by wireline logging tools. The samples with higher gamma ray and neutron porosity are expected to have greater clay content, and thus less effective porosity and permeability.

关键词： spontaneous imbibition wettability petrophysics gamma ray log

Oscillation Criteria of Second Order Half Linear Delay Dynamic Equations on Time Scales

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Acta mathematicae Applicatae Sinica 2017年第1期33卷 83-92页

作者： H.A. AGWO A.m.m. KHODIER HEBA A. hassan Department of mathematics Faculty of Education Ain Shams University 11757 beside Tabary school RoxyCairo Egypt

In this paper, we establish some new oscillation criteria for a non autonomous second order delay dynamic equation （r（t）g（x△（t）））△＋p（t）f（x（τ（t）））=0 on a time scale T. Oscillation behavior of this equation is not studied before. Our results not only apply on differential equations when T=R, difference equations when T=N but can be applied on different types of time scales such as when T=N for q〉1 and also improve most previous results. Finally, we give some examples to illustrate our main results.

关键词： time scales oscillation second order delay dynamic equations generalized Riccati technique generalized exponential function

Determining the mechanism behind yoga’s effects on preventing the symptoms of Alzheimer’s disease

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Neural Regeneration Research 2020年第2期15卷 261-262页

作者： Adithy hassan meghan Robinson Stephanie m. Willerth Division of medical Sciences 3800 Finnerty RoadUniversity of VictoriaVictoriaBritish ColumbiaCanada The Vancouver Prostate Centre VancouverBritish ColumbiaCanada Department of mechanical Engineering University of VictoriaVictoriaBritish ColumbiaCanadaCentre for Biomedical ResearchUniversity of VictoriaVictoriaBritish ColumbiaCanadaInternational Collaboration on Repair DiscoveriesUniversity of British ColumbiaVancouverBritish ColumbiaCanada

Background on the relationship between meditation/yoga practice and its effect on Alzheimer's disease (AD): Dementia refers to a variety of conditions that affect the normal function of the brain, leading to symptoms like memory loss, issues with problem solving, difficulty in processing thoughts and disordered language (mcKhann et al., 2011).

关键词： effects yoga Alzheimer's disease

Effects of Zr substitution on structural,morphological,and magnetic properties of bismuth iron oxide phases

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Chinese Physics B 2017年第8期26卷 450-455页

作者： A Asif m hassan S Riaz S Naseem S S Hussain materials Growth and Simulation Laboratory Department of PhysicsUniversity of the PunjabLahore-54590Pakistan Center of Excellence in Solid State Physics University of the PunjabLahore-54590Pakistan

The present study involves co-precipitation method to grow un-doped and Zr-doped bismuth iron oxide with x_（Zr）=0.10–0.30. The molar solutions of ferric chloride（FeCl_3）, zirconyle chloride（ZrOCl_2）, and bismuth chloride（BiCl_3） are prepared in distilled water, and are allowed to react with sodium hydroxide（Na OH）. The synthesized powders are then converted into pellets, which are sintered at 500℃ for two hours in a muffle furnace. X-ray diffraction（XRD） shows multi-phase formation in un-doped and Zr doped samples. Scanning electron microscope（SEm） depicts layered structure at low Zr concentration x_（Zr）= 0.10, while uniform surface with smaller grains and voids is observed at x_（Zr）= 0.20, but at x_（Zr）= 0.30, cracks and voids become prominent. The ferromagnetic nature of the un-doped sample is observed by vibrating sample magnetometer（VSm）, while paramagnetic behavior appears due to Zr doping. The ferromagnetism in un-doped sample is lost by Zr doping, which is due to the formation of additional Fe–O–Zr bonds that induce paramagnetic behavior.

关键词： co-precipitation multi-phases ferromagnetism paramagnetism BiFeO3

A study of the operating parameters and barrier thickness of Al_(0.08)In_(0.08)Ga_(0.84)N/Al_xIn_yGa_(1-x-y)N double quantum well laser diodes

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Science China(Technological Sciences) 2011年第1期54卷 47-51页

作者： A.J.GHAZAI S.m.THAHAB H.ABU hassan Z.hassan Nano-Optoelectronics Research and Technology Laboratory School of PhysicsUniversiti Sains Malaysia material Engineering Department College of EngineeringUniversity of Kufa

The operating parameters such as the internal quantum efficiency （η）, internal loss （α） and transparent threshold current density （J0） of double quantum well laser diodes were investigated and identified using the program, Integrated System Engineering-Technical Computer Aided Design （ISE-TCAD）. Various thicknesses （6, 7, 8, 10, 12 rim） of AlxInyGa1-x-yN barriers with （3 nm） Al0.08In0.08Ga0.84N wells as an active region were studied. The lowest threshold current （lth）, and the highest output power （Pop） were 116 mA and 196 mW respectively, at barriers thickness of 6 nm, Al mole fraction of 10% and In mole fraction of 1%, at an emission wavelength of 359.6 nm.

关键词： AIInGaN quaternary UV laser diode quantum well barrier thickness

Hybrid Sensor Selection Technique for Lifetime Extension of Wireless Sensor Networks

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Computers, materials & Continua 2022年第3期70卷 4965-4985页

作者： Khaled m.Fouad Basma m.hassan Omar m.Salim Information Systems Department Faculty of Computers and Artificial IntelligenceBenha UniversityBenha13518Egypt Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikh33516Egypt Electrical Engineering Department Benha Faculty of EngineeringBenha UniversityBenha13518Egypt

Energy conservation is a crucial issue to extend the lifetime of wireless sensor networks(WSNs)where the battery capacity and energy sources are very *** energy-saving techniques can help designers overcome this issue by reducing the number of selected sensors that report environmental measurements by eliminating all replicated and unrelated *** paper suggests a Hybrid Sensor Selection(HSS)technique that combines filter-wrappermethod to acquire a rich-informational subset of sensors in a reasonable *** aims to increase the lifetime of WSNs by using the optimal number of *** the same time,HSS maintains the desired level of accuracy and manages sensor failures with the most suitable number of sensors without compromising the *** evaluation of the HSS technique has adopted four experiments by using four different *** experiments show that HSS can extend the WSNs lifetime and increase the accuracy using a sufficient number of sensors without affecting ***,to ensure HSS credibility and reliability,the proposed HSS technique has been compared to other corresponding methodologies and shows its superiority in energy conservation at premium accuracy measures.

关键词： Energy conservation WSNs intelligent techniques sensor selection

A multi-Factor Authentication-Based Framework for Identity management in Cloud Applications

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Computers, materials & Continua 2022年第5期71卷 3193-3209页

作者： Wael Said Elsayed mostafa m.m.hassan Ayman mohamed mostafa Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt College of Computer and Information Sciences Jouf UniversitySakaka72314Saudi Arabia

User’s data is considered as a vital asset of several *** data to the cloud computing is not an easy decision for any organization due to the privacy and security *** providers must ensure that both data and applications that will be stored on the cloud should be protected in a secure *** data stored on the public cloud will be vulnerable to outside and inside *** paper provides interactive multi-layer authentication frameworks for securing user identities on the *** access control policies are applied for verifying users on the cloud.A security mechanism is applied to the cloud application that includes user registration,granting user privileges,and generating user authentication *** intrusion detection system is embedded to the security mechanism to detect malicious *** multi factor authentication,intrusion detection,and access control techniques can be used for ensuring the identity of the ***,encryption techniques are used for protecting the data from being *** results are carried out to verify the accuracy and efficiency of the proposed frameworks and *** results recorded high detection rate with low false positive alarms.

关键词： Cloud computing service providers multi-layer authentication frameworks and access control

Dental Age Estimation Based on X-ray Images

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Computers, materials & Continua 2020年第2期62卷 591-605页

作者： Noor mualla Essam H Houssein m.R.hassan Computer Science Branch Mathematics DepartmentFaculty of ScienceAswan UniversityAswanEgypt Department of Computer Science Faculty of Computers and InformationMinia UniversityMinyaEgypt

Chronological age estimation using panoramic dental X-ray images is an essential task in forensic *** statistical approaches have proposed by considering the teeth and ***,building automated dental age estimation based on machine learning techniques needs more research *** this paper,an automated dental age estimation is proposed using transfer *** the proposed approach,features are extracted using two deep neural networks namely,AlexNet and *** classifiers are proposed to perform the classification task including decision tree,k-nearest neighbor,linear discriminant,and support vector *** proposed approach is evaluated using a number of suitable performance metrics using a dataset that contains 1429 dental X-ray *** obtained results show that the proposed approach has a promising performance.

关键词： Classification dental age estimation transfer learning X-ray images