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TiC-Maraging stainless steel composite:microstructure, mechanical and wear properties

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Rare Metals 2006年第6期25卷 630-635页

作者： Akhtar Farid Khadijah ali shah syed Javid Askari School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Particulate TiC reinforced 17-4PH and 465 maraging stainless steel matrix composites were processed by conventional powder metallurgy （P/M）. TiC-maraging stainless steel composites with theoretical density 〉97% were produced using conventional P/M. The microstructure, and mechanical and wear properties of the composites were evaluated. The microstructure of the composites consisted of （core-rim structure） spherical and semi-spherical TiC particles depending on the wettability of the matrix with TiC particles. In TiC-maraging stainless steel composites, 465 stainless steel binder phase showed good wettability with TiC particles. Some microcracks appeared in the composites, indicating the presence of tensile stresses in the composites produced during sintering. The typical properties, hardness, and bend strength were reported for the composites. After heat treatment and aging, an increase in hardness was observed. The increase in hardness was at- tributed to the aging reaction in maraging stainless steel. The specific wear behavior of the composites strongly depends on the content of TiC particles and their interparticle spacing, and on the heat treatment of the maraging stainless steel.

关键词： TiC-maraging stainless steel composites aging wear powder metallurgy microcracks

Fractional Analysis of Thin Film Flow of Non-Newtonian Fluid

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 825-845页

作者： Farnaz Ismail Mubashir Qayyum syed Inayat ali shah Department of Mathematics Islamia College UniversityPeshawarPakistan Department of Sciences and Humanities National University of Computer&Emerging Sciences FASTLahorePakistan

Modeling and analysis of thin film flow with respect to magneto hydro dynamical effect has been an important theme in the field of fluid dynamics,due to its vast industrial *** analysis involves studying the behavior and response of governing equations on the basis of various parameters such as thickness of the film,film surface profile,shear stress,liquid velocity,volumetric flux,vorticity,gravity,viscosity among others,along with different boundary *** this article,we extend this analysis in fractional space using a homotopy based scheme,considering the case of a Non-Newtonian Pseudo-Plastic fluid for lifting and drainage on a vertical *** applying similarity transformations,the given problems are reduced to highly non-linear and inhomogeneous ordinary differential ***,fractional differential equations are obtained using basic definitions of fractional *** Homotopy Perturbation Method(HPM),along with fractional calculus is used for obtaining approximate *** quantities such as the velocity profile,volume flux and average velocity respectively for lift and drainage cases have been *** the best of our knowledge,the given problems have not been attempted before in fractional *** and convergence of the obtained solutions are confirmed by finding residual *** a physical perspective,a comprehensive study of the effects of various parameters on the velocity profile is also *** reveals that Stokes number St,non-Newtonian parameterand magnetic parameter M have inverse relationship with fluid velocity in lifting *** the drainage case,Stokes number St and non-Newtonian parameterhave direct relationship with fluid velocity,but magnetic parameter M shows inverse relationship with *** investigation also shows that the fractional parameterhas direct relationship with the fluid velocity in lifting case,while it has inverse relationship with velocity in the

关键词： Pseudo-plastic fluid magneto hydro dynamic fractional differential equation homotopy perturbation method

An Energy-Efficient 12b 2.56 MS/s SAR ADC Using Successive Scaling of Reference Voltages

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Computers, Materials & Continua 2022年第7期72卷 2127-2139页

作者： Hojin Kang syed Asmat ali shah HyungWon Kim Department of Electronics Engineering College of Electrical and Computer EngineeringChungbuk National UniversityCheongju28644Korea Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusAbbottabad22060Pakistan

This paper presents an energy efficient architecture for successive approximation register(SAR)analog to digital converter(ADC).SAR ADCs with a capacitor array structure have been widely used because of its simple architecture and relatively high ***,conventional SAR ADCs consume relatively high energy due to the large number of capacitors used in the capacitor array and their sizes scaled up along with the number of *** proposed architecture reduces the energy consumption as well as the capacitor size by employing a new array architecture that scales down the reference voltages instead of scaling up the capacitor *** proposed 12-bit SAR ADC is implemented in Complementary Metal Oxide Semiconductor(CMOS)0.13 um library using Cadence Virtuoso design *** results and mathematical model demonstrate the overall energy savings of up to 97.3%compared with conventional SAR ADC,67%compared with the SAR ADC with split capacitor,and 35%compared with the resistor and capacitor(R&C)Hybrid SAR *** ADC achieves an effective number of bits(ENOB)of 11.27 bits and consumes 61.7 uW at sampling rate of 2.56 MS/s,offering an energy consumption of 9.8 fJ per conversion *** proposed SAR ADC offers 95.5%reduction in chip core area compared to conventional architecture,while occupying an active area of 0.088 mm2.

关键词： Low voltage low power successive approximation register analog to digital converter switching energy

RBF Based Localized Method for Solving Nonlinear Partial Integro-Differential Equations

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Computer Modeling in Engineering & Sciences 2020年第6期123卷 957-972页

作者： Marjan Uddin Najeeb Ullah syed Inayat ali shah University of Engineering and Technology PeshawarPakistan Islamia College University PeshawarPakistan

In this work,a numerical scheme is constructed for solving nonlinear parabolictype partial-integro differential *** proposed numerical scheme is based on radial basis functions which are local in nature like finite difference numerical *** radial basis functions are used to approximate the derivatives involved and the integral is approximated by equal width integration *** resultant differentiation matrices are sparse in *** spatial approximation using RBF the partial integro-differential equations reduce to the system of *** ODEs system can be solved by various types of ODE *** proposed numerical scheme is tested and compared with other methods available in literature for different test *** stability and convergence of the present numerical scheme are discussed.

关键词： RBFs integral equations local method

Recent advances and emerging trends of rare-earth-ion doped spectral conversion nanomaterials in perovskite solar cells

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Journal of Rare Earths 2022年第11期40卷 1651-1667,I0001页

作者： syed Afaq ali shah Muhammad Hassan Sayyad Jinghua Sun Zhongyi Guo School of Electrical Engineering&Intelligentization Dongguan University of TechnologyDongguan 523808China Advanced Photovoltaic Research Labs(APRL) Faculty of Engineering SciencesGhulam Ishaq Khan Institute of Engineering Sciences and TechnologyTopiDistrictSwabiKhyberPakhtunkhwa23640Pakistan School of Computer and Information Hefei University of TechnologyHefei 2300o9China

Organic-inorganic lead halide based perovskite solar cells(PSCs)have attracted unprecedented research interest over last *** high performance,combined with merits of low fabrication costs and ease of synthesis make PSCs promising alternate to state of the art silicon(Si)based solar *** r,some inherent shortcomings of PSCs are hindering their market dominance over conventional photovoltaic technologies such as transmission loss of sub-bandgap photons,poor stability and hysteresis ***,use of rare earth(RE)ions doped nanomaterials in PSCs,has been identified as an effective means to address the aforementioned issues by expanding the range of absorption spectra minimizing the non-absorption loss of solar photons,enhancing light scattering and improving operational *** article reviews the recent progress in doping rare-earth(RE)ions in the building blocks of PSCs such as semiconductor electrodes and photoactive perovskite layers,and its use as a separate spectral conversion layer in *** effect of size,shape,constitution and concentration of RE-nanoparticles on the overall performance and device stability will be analyzed in ***,we provide an outlook on the opportunities this newly developed field offers and the critical challenges faced in rationally and effectively using RE-ion-doped nanomaterials in PSCs for better operational stability and enhanced performance.

关键词： Efficiency Electron transport layer Photovoltaics Rare-earth(RE) Perovskite solar cells Up/down conversion

Structural Analysis of the SARS-CoV-2 Omicron Variant Proteins

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Research 2021年第2期2021卷 759-762页

作者： Qiangzhen Yang ali Alamdar shah syed Aamir Fahira Yongyong Shi Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education)Shanghai Jiao Tong University1954 Huashan RoadShanghai 200030China Biomedical Sciences Institute of Qingdao University(Qingdao Branch of SJTU Bio-X Institutes) Qingdao UniversityQingdao 266003China Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghai 200030China Shanghai Key Laboratory of Sleep Disordered Breathing Shanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghaiChina The First Affiliated Hospital of Zhengzhou University Zhengzhou 450052China Department of Psychiatry First Teaching Hospital of Xinjiang Medical UniversityUrumqi830046China

The spread of the latest SARS-CoV-2 variant Omicron is particularly concerning because of the large number of mutations present in its genome and lack of knowledge about how these mutations would affect the current SARS-CoV-2 vaccines and ***,by performing phylogenetic analysis using the Omicron spike(S)protein sequence,we found that the Omicron S protein presented the longest evolutionary distance in relation to the other SARS-CoV-2 *** predicted the structures of S,M,and N proteins of the Omicron variant using AlphaFold2 and investigated how the mutations have affected the S protein and its parts,S1 NTD and RBD,in *** found many amino acids on RBD were mutated,which may influence the interactions between the RBD and ACE2,while also showing the S309 antibody could still be capable of neutralizing Omicron *** Omicron S1 NTD structures display significant differences from the original strain,which could lead to reduced recognition by antibodies resulting in potential immune escape and decreased effectiveness of the existing ***,this study of the Omicron variant was mainly limited to structural predictions,and these findings should be explored and verified by subsequent *** study provided basic data of the Omicron protein structures that lay the groundwork for future studies related to the SARS-CoV-2 Omicron variant.

关键词： concerning subsequent neutral

Machine learning empowered COVID-19 patient monitoring using non-contact sensing:An extensive review

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Journal of Pharmaceutical Analysis 2022年第2期12卷 193-204页

作者： Umer Saeed syed Yaseen shah Jawad Ahmad Muhammad ali Imran Qammer H.Abbasi syed Aziz shah Research Centre for Intelligent Healthcare Coventry UniversityCoventryCV15FBUK School of Computing Engineering and Built EnvironmentGlasgow Caledonian UniversityGlasgowG40BAUK School of Computing Edinburgh Napier UniversityEdinburghEH114BNUK James Watt School of Engineering University of GlasgowGlasgowG128QQUK

The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which caused the coronavirus disease 2019(COVID-19)pandemic,has affected more than 400 million people *** the recent rise of new Delta and Omicron variants,the efficacy of the vaccines has become an important *** goal of various studies has been to limit the spread of the virus by utilizing wireless sensing technologies to prevent human-to-human interactions,particularly for healthcare *** this paper,we discuss the current literature on invasive/contact and non-invasive/noncontact technologies(including Wi-Fi,radar,and software-defined radio)that have been effectively used to detect,diagnose,and monitor human activities and COVID-19 related symptoms,such as irregular *** addition,we focused on cutting-edge machine learning algorithms(such as generative adversarial networks,random forest,multilayer perceptron,support vector machine,extremely randomized trees,and k-nearest neighbors)and their essential role in intelligent healthcare ***,this study highlights the limitations related to non-invasive techniques and prospective research directions.

关键词： Artificial intelligence Non-invasive healthcare Machine learning Non-contact sensing COVID-19

Fractional Processing Based Adaptive Beamforming Algorithm

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Computers, Materials & Continua 2023年第7期76卷 1065-1084页

作者： syed Asghar ali shah Tariqullah Jan syed Muslim shah Ruhul Amin Khalil Ahmad Sawalmeh Muhammad Anan Department of Electrical Engineering University of Engineering and TechnologyPeshawar25120Pakistan Department of Electrical Engineering Capital University of Science and TechnologyIslamabad44000Pakistan Department of Computer Science Northern Border UniversityArar91431Saudi Arabia Department of Software Engineering Alfaisal UniversityRiyadh11533Saudi Arabia

Fractional order algorithms have shown promising results in various signal processing applications due to their ability to improve performance without significantly increasing *** goal of this work is to inves-tigate the use of fractional order algorithm in the field of adaptive beam-forming,with a focus on improving performance while keeping complexity *** effectiveness of the algorithm will be studied and evaluated in this *** this paper,a fractional order least mean square(FLMS)algorithm is proposed for adaptive beamforming in wireless applications for effective utilization of *** algorithm aims to improve upon existing beam-forming algorithms,which are inefficient in performance,by offering faster convergence,better accuracy,and comparable computational *** FLMS algorithm uses fractional order gradient in addition to the standard ordered gradient in weight *** derivation of the algorithm is provided and supported by mathematical convergence *** is evaluated through simulations using mean square error(MSE)minimization as a metric and compared with the standard LMS algorithm for various *** results,obtained through Matlab simulations,show that the FLMS algorithm outperforms the standard LMS in terms of convergence speed,beampattern accuracy and scatter *** outperforms LMS in terms of convergence speed by 34%.From this,it can be concluded that FLMS is a better candidate for adaptive beamforming and other signal processing applications.

关键词： Adaptive beamforming adaptive array fractional processing least mean square fractional least mean square

A macroscopic traffic model based on weather conditions

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Chinese Physics B 2018年第7期27卷 179-189页

作者： Zawar H.Khan syed Abid ali shah T.Aaron Gulliver Department of Electrical Engineering University of Engineering and TechnologyPeshawarPakistan Department of Electrical and Computer Engineering University of VictoriaPO Box 1700STN CSCVictoriaBC Canada

A traffic model based on the road surface conditions during adverse weather is presented. The surface of a road is affected by snow, compacted snow, and ice, which affects the traffic behavior. In this paper, a new macroscopic traffic flow model based on the transition velocity distribution is proposed which characterizes traffic alignment under adverse weather conditions. Two examples are considered to illustrate the effect of the transition velocity behavior on traffic velocity and density. Simulation results are presented which show that this model provides a more accurate characterization of traffic flow behavior than the well known Payne-Whitham model. The proposed model can be used to reduce accidents and improve road safety during adverse weather conditions.

关键词： macroscopic traffic flow anticipation Payne-Witham (PW) model adverse weather