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Combined heat and mass transfer by mixed convection MHD flow along a porous plate with chemical reaction in presence of heat source

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Applied Mathematics and Mechanics(English Edition) 2010年第10期31卷 1217-1230页

作者： J.ZUECO s.ahmed ETs Ingeniería Industrial Departamento de Ingeniería Térmicay FluidosUniversidad Politécnica de Cartagena Fluid Dynamics Research Department of MathematicsGoalpara College

An exact and a numerical solutions to the problem of a steady mixed convective MHD flow of an incompressible viscous electrically conducting fluid past an infinite vertical porous plate with combined heat and mass transfer are presented.A uniform magnetic field is assumed to be applied transversely to the direction of the flow with the consideration of the induced magnetic field with viscous and magnetic dissipations of energy.The porous plate is subjected to a constant suction velocity as well as a uniform mixed stream velocity.The governing equations are solved by the perturbation technique and a numerical method.The analytical expressions for the velocity field,the temperature field,the induced magnetic field,the skin-friction,and the rate of heat transfer at the plate are obtained.The numerical results are demonstrated graphically for various values of the parameters involved in the problem.The effects of the Hartmann number,the chemical reaction parameter,the magnetic Prandtl number,and the other parameters involved in the velocity field,the temperature field,the concentration field,and the induced magnetic field from the plate to the fluid are discussed.An increase in the heat source/sink or the Eckert number is found to strongly enhance the fluid velocity values.The induced magnetic field along the x-direction increases with the increase in the Hartmann number,the magnetic Prandtl number,the heat source/sink,and the viscous dissipation.It is found that the flow velocity,the fluid temperature,and the induced magnetic field decrease with the increase in the destructive chemical reaction.Applications of the study arise in the thermal plasma reactor modelling,the electromagnetic induction,the magnetohydrodynamic transport phenomena in chromatographic systems,and the magnetic field control of materials processing.

关键词： MHD perturbation technique network simulation method Eckert number mixed convection induced magnetic field viscous dissipation heat source/sink

Formation of Co-implanted silicon Ultra-shallow Junctions for Low Thermal Budget Applications

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Chinese Physics Letters 2013年第1期30卷 127-129页

作者： Rehana Mustafa s.ahmed E.U.Khan Department of Physics International Islamic UniversityIslamabadPakistan Advanced Electronics Laboratory Faculty of Engineering&TechnologyInternational Islamic University IslamabadPakistan Center for Emerging sciences Engineering and TechnologyIslamabadPakistan Department of Physics Gomal UniversityD.I.KhanPakistan

We present a systematic study to create ultra-shallow junctions in n-type silicon substrates and investigate both pre-and post-annealing processes to create a processing strategy for potential applications in nano-devices.starting wafers were co-implanted with indium and C atoms at energies of 70 keV and 10 keV,respectively.A carefully chosen implantation schedule provides an abrupt ultra-shallow junction between 17 and 43 nm with suppressed sheet resistance and appropriate retained sheet carrier concentration at low thermal budget.A defect doping matrix,primarily the behavior and movement of co-implant generated interstitials at different annealing temperatures,may be engineered to form sufficiently activated ultra-shallow devices.

关键词： shallow annealing implantation

Preparation and Characterization of Boron Thin Film on Iron substrate

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Journal of Materials science & Technology 2007年第4期23卷 481-486页

作者： Ishrat REHANA D.Muhammad s.ahmed J.I.Akhter Central Analytical Facility Division Pakistan Institute of Nuclear science and Technology NiloreIslamabadPakistan Physics Radiation Division Pakistan Institute of Nuclear science and Technology NiloreIslamabadPakistan

支持者热 layering 被化学蒸汽免职( CVD )承担在温度的极端纯 CH3OH.The 影响的硼酸的方法使用饱和溶液被在大多数最佳温度被发现是时间的 200 deg C.The 效果的 borondeposition.The 的过程期间从 100～600 deg C 改变温度学习跨... 详细信息

支持者热 layering 被化学蒸汽免职( CVD )承担在温度的极端纯 CH3OH.The 影响的硼酸的方法使用饱和溶液被在大多数最佳温度被发现是时间的 200 deg C.The 效果的 borondeposition.The 的过程期间从 100～600 deg C 改变温度学习跨度从 6～120 h.The 产生被观察微或nano规模厚度能被完成实验的牛棚 ducing 时间跨度。CVD 的行为被使用扫描电子显微镜，吸收度 spectrohotometer 和原子排放摄谱仪描绘。

关键词：硼化学药品蒸汽沉积物电子扫描显微镜法原子发射摄谱仪吸光度分光光度计薄膜

采用有限元法设计电磁成形的非均匀线圈(英文)

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Transactions of Nonferrous Metals society of China 2011年第3期21卷 618-625页

作者： M.ahmed1 s.K.PANTHI N.RAMAKRIsHNAN A.K.JHA A.H.YEGNEsWARAN R.DAsGUPTA s.ahmed Advanced Materials and Processes Research Institute(AMPRI) Bhopal -462064 India India science Laboratory GM Bangalore-560066 India Maulana Azad National Institute of Technology ( MANIT) Bhopal-462007 India

电磁成形是一种使用脉冲电磁力快速成形的工艺。线圈是电磁成形系统中的一个重要组成部分,需要根据实际应用情况来设计。均匀螺旋线圈通常用在金属板材零件成形中。然而,对于这类非均匀线圈,工件中心部位的电磁力弱,从而导致变形不充分... 详细信息

电磁成形是一种使用脉冲电磁力快速成形的工艺。线圈是电磁成形系统中的一个重要组成部分,需要根据实际应用情况来设计。均匀螺旋线圈通常用在金属板材零件成形中。然而,对于这类非均匀线圈,工件中心部位的电磁力弱,从而导致变形不充分并且还有其它问题出现,如滞留气泡。因此,提出一个设计非均匀线圈的概念,以便电磁力的分布更均匀。采用有限元法对提出的非均匀线圈与传统的均匀螺旋线圈就电磁力的分布、磁场和电流密度进行比较。结果表明,非均匀线圈的电磁力分布更均匀。还计算了线圈的感应强度并进行了比较。

关键词：电磁成形螺旋线圈金属板材成形有限元法

Mobile Fog Computing by Using sDN/NFV on 5G Edge Nodes

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Computer systems science & Engineering 2022年第5期41卷 751-765页

作者： G.R.sreekanth s.ahmed Najat ahmed Marko sarac Ivana strumberger Nebojsa Bacanin Miodrag Zivkovic Department of Computer science and Engineering Kongu Engineering CollegeErode638060India Department of Computer Engineering Lebanese French UniversityErbil44001Iraq singidunum University Belgrade11000Serbia

Abstract:Fog computing provides quality of service for cloud infrastructure.As the data computation intensifies,edge computing becomes difficult.Therefore,mobile fog computing is used for reducing traffic and the time for data computation in the network.In previous studies,software-defined networking(sDN)and network functions virtualization(NFV)were used separately in edge computing.Current industrial and academic research is tackling to integrate sDN and NFV in different environments to address the challenges in performance,reliability,and scalability.sDN/NFV is still in development.The traditional Internet of things(IoT)data analysis system is only based on a linear and time-variant system that needs an IoT data system with a high-precision model.This paper proposes a combined architecture of sDN and NFV on an edge node server for IoT devices to reduce the computational complexity in cloud-based fog computing.sDN provides a generalization structure of the forwarding plane,which is separated from the control plane.Meanwhile,NFV concentrates on virtualization by combining the forwarding model with virtual network functions(VNFs)as a single or chain of VNFs,which leads to interoperability and consistency.The orchestrator layer in the proposed software-defined NFV is responsible for handling real-time tasks by using an edge node server through the sDN controller via four actions:task creation,modification,operation,and completion.Our proposed architecture is simulated on the EstiNet simulator,and total time delay,reliability,and satisfaction are used as evaluation parameters.The simulation results are compared with the results of existing architectures,such as software-defined unified virtual monitoring function and AsTP,to analyze the performance of the proposed architecture.The analysis results indicate that our proposed architecture achieves better performance in terms of total time delay(1800 s for 200 IoT devices),reliability(90%),and satisfaction(90%).

关键词： Mobile fog computing edge computing edge node IoT softwaredefined networking network functions virtualization orchestrator

Egyptian heavy vacuum gas oil hydrotreating over Co-Mo/CNT and Co-Mo/γ-Al2O3 catalysts

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燃料化学学报 2016年第7期44卷 853-861页

作者： W.ahmed Hoda,s.ahmed H.s.El-sheshtawy Nadia,A.Mohamed Asmaa,I.Zahran Egyptian Petroleum Research Institute 1Aahmed El-Zomor st.Naser city 11727CairoEgypt Ain-shams University for Girls Roqqsy SquireCairoEgypt

The catalytic activity of CoMos /CNT towards the Egyptian heavy vacuum gas oil hydrotreating was studied. The delivered CNT was functionalized with 6 mol /L HNO_3. The CNT were loaded with 12% MoO_3( by weight) and 0.7 Co /Mo atomic ratio with impregnation methods. The γ-Al_2O_3 catalyst was also prepared by impregnation method to compare both catalysts activities.The analysis tools such XRD,Raman spectroscopy,TEM,and BET were used to characterize the catalysts. The autoclave reactor was used to operate the hydrotreating experiments. The hydrotreating reactions were tested at various operating conditions of temperature 325-375 ℃,pressure 2-6 MPa,time 2-6 h,and catalyst /oil ratio( by weight) of 1 ∶75,1 ∶33 and 1 ∶10. The results revealed that the CoMos /CNT was highly efficient for the hydrotreating more than the CoMos /γ-Al_2O_3. Also, the hydrodesulfurization( HDs) increased with increasing catalyst /oil ratio. Additionally,results showed that the optimum condition was temperature 350℃,pressure 4 MPa,catalyst /oil ratio of 1 ∶75 for 2 h. Furthermore,even at low CoMos /CNT catalyst /oil ratio of 1 ∶75,an acceptable HDs of 77.1% was achieved.

关键词： hydrotreatment hydrodesulfurization carbon nanotube heavy vacuum gas oil(HVGO)

Neurocysticercosis:A case report and brief review

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Asian Pacific Journal of Tropical Medicine 2016年第1期9卷 98-100页

作者： syed A.A.Rizvi Ayman M.saleh Hanns Frimpong Hussain M.Al Mohiy Jasmin ahmed Ronda D.Edwards sultan s.ahmed College of Pharmacy Nora Southeastern University JAs Medical Management LLC Department of Basic Medical sciences College of MedicineKing Saud Bin Abdulaziz University for Health SciencesNational Guard Health Affairs Radiological sciences Department College of Applied Medical SciencesKing Khalid University Herbert Wertheim College of Medicine Florida International University school of Medicine Spartan Health Science University

Neurocysticercosis(NCC) is one of the seven neglected endemic zoonoses targeted by the World Health Organization.It is considered a common infection of the nervous system caused by the Tanenia solium and is known to be the primary cause of preventable epilepsy in many developing countries.NCC is commonly resulted by the ingestion of Tanenia solium eggs after consuming undercooked pork,or contaminated water.The parasite can grow in the brain and spinal cord within the nervous system,causing severe headache and seizures beside other pathological manifestations.Immigration and international travel to endemic countries has made this disease common in the United states.NCC can be diagnosed with computed tomography and magnetic resonance imaging of the brain.The treatment of the NCC including cysticidal drugs(eg.,albendazole and praziquantel),and neurosurgical procedure,depending upon a the situation.A patient of Asian origin came to our clinic with complaints of dizziness,headaches and episodes seizures for the past twelve years without proper diagnosis.The computed tomography and magnetic resonance imaging scans indicated multilobulated cystic mass in the brain with the suspicion of neurocysticercosis.

关键词： Neurocysticercosis Tanenia solium Epilepsy Magnetic resonance imaging Computed Tomography

Benign lymph node microenvironment is associated with response to immunotherapy

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Precision Clinical Medicine 2020年第1期3卷 44-53页

作者： Maria I.Toki Deepika Kumar Fahad s.ahmed David L.Rimm Mina L.Xu Department of Pathology Yale University School of MedicineNew HavenCT 06510USA Department of Medicine Yale University School of MedicineNew HavenCT 06510USA

Introduction:Benign lymph nodes have been considered the hubs of immune surveillance in cancer patients.The microenvironment of these lymphoid tissues can be immune suppressed,hence allowing for tumor progression.Understanding the spectrum of benign findings in bystander lymph nodes in immune checkpoint blockade therapy could prove to be key to understanding the mechanism and assessing treatment response.Methods:Benign lymph nodes and spleen were evaluated from patients treated with immunotherapy who subsequently received postmortem examination.We used quantitative immunofluorescence(QIF)to assess tumor infiltrating lymphocytes(TIL)and macrophage marker expression and characterized activation status using a novelmultiplexed QIF assay including CD3,GranzymeB,and Ki67.We performedimmunohistochemistry to correlate results of QIF.Results:Benign lymph nodes from non-responders to immunotherapy showed significantly higher expression of cytotoxic markers and proliferation index(Ki67)in T cells compared to responders.Higher expression of PD-L1 in macrophages was also observed.There was no significant difference in CD3+expression,but higher levels of CD8+T cells as well as CD20+B cells were seen in lymph nodes of non-responders.No significant differences were seen between responder and non-responder splenic tissue.Findings were supported by traditional immunostaining methods.Conclusions:While most studies in biomarkers for immunotherapy focus on tumor microenvironment,we show that benign lymph node microenvironment may predict response to immunotherapy.In responding patients,bystander lymph nodes appear to have been mobilized,resulting in reduced cytotoxic T cells.Conversely,patients whose disease progressed on immunotherapy demonstrate higher levels of macrophages that express increased PD-L1,and activated T cells not recruited to the tumor site.

关键词： response to immunotherapy lymph node microenvironment quantitative immunofluorescence

Automatic Channel Detection Using DNN on 2D seismic Data

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Computer systems science & Engineering 2021年第1期36卷 57-67页

作者： Fahd A.Alhaidari saleh A.Al-Dossary Ilyas A.salih Abdlrhman M.salem ahmed s.Bokir Mahmoud O.Fares Mohammed I.ahmed Mohammed s.ahmed Imam Abdulrahman Bin Faisal University College of Computer Science and Information TechnologyDammam34212Saudi Arabia saudi Aramco Oil Company EXPEC-IIDhahranSaudi Arabia

Geologists interpret seismic data to understand subsurface properties and subsequently to locate underground hydrocarbon resources.Channels are among the most important geological features interpreters analyze to locate petroleum reservoirs.However,manual channel picking is both time consuming and tedious.Moreover,similar to any other process dependent on human intervention,manual channel picking is error prone and inconsistent.To address these issues,automatic channel detection is both necessary and important for efficient and accurate seismic interpretation.Modern systems make use of real-time image processing techniques for different tasks.Automatic channel detection is a combination of different mathematical methods in digital image processing that can identify streaks within the images called channels that are important to the oil companies.In this paper,we propose an innovative automatic channel detection algorithm based on machine learning techniques.The new algorithm can identify channels in seismic data/images fully automatically and tremendously increases the efficiency and accuracy of the interpretation process.The algorithm uses deep neural network to train the classifier with both the channel and non-channel patches.We provide a field data example to demonstrate the performance of the new algorithm.The training phase gave a maximum accuracy of 84.6%for the classifier and it performed even better in the testing phase,giving a maximum accuracy of 90%.

关键词： Deep neural networks deep learning channel detection image processing two-dimensional seismic data