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Computer Modeling in Engineering & Sciences 2021年第1期126卷 241-259页

作者： Tina Chaudhary Arshad Noor Siddiquee Arindam Kumar Chanda Shafi Ahmad Irfan Anjum Badruddin zahid a.khan Department of Mechanical and Automation Engineering Indira Gandhi Delhi Technical University for WomenKashmere Gate110006India Department of Mechanical Engineering Jamia Millia Islamia(A Central University)New Delhi110025India Department of Mechanical and Automation Engineering G.B.Pant Engineering CollegeNew Delhi110020India Mechanical Engineering Department College of EngineeringKing Khalid UniversityAbha-61421AsirSaudi Arabia

The purpose of this research is to obtain the optimum cutting parameters to achieve the dimensional accuracy of Nimonic alloy miniature gear manufactured using Wire *** cutting parameters investigated in this study are current,pulse on time(PON),pulse off time(POFF),wire tension(WT)and dielectric *** glycol,nanopowder of alumina and oxygen are mixed to demineralized water to prepare novel dielectric *** in inner diameter,deviation in outer diameter,deviation in land and deviation in tooth width are considered to check the dimensional *** L_(16) is employed for experimental design and multiple response optimization is performed using Entropy TOPSIS and Pareto *** indicate that pulse on time is the most notable parameter for good dimensional accuracy followed by dielectric fluid,current,pulse off time and wire *** glycol mixed demineralized water is preferred for low dimensional *** optimum WEDM parameters are pulse on time at 20μs,Ethylene glycol mixed demineralized water dielectric fluid,current at 3 A,pulse off time at 4μs,and wire tension at 18 N.

关键词： Miniature gear multiple optimization dimensional accuracy entropy TOPSIS Pareto ANOVA

Friction stir welding of aluminum to copper—An overview

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Transactions of Nonferrous Metals Society of China 2017年第10期27卷 2113-2136页

作者： Nidhi SHARMA zahid a.khan Arshad Noor SIDDIQUEE Department of Mechanical Engineering Jamia Millia Islamia New Delhi India

Components made by joining different materials are required in various engineering *** of suchcomponents is a challenging task due to the vast difference in mechanical,thermal and electrical properties of the materials *** stir welding(FSW)is capable of joining dissimilar materials such as aluminum(Al)and copper(Cu)and thereforeresearchers have used this novel process for dissimilar ***,several works pertaining to dissimilar joining,specifically Al?Cu,are available in the literature but they are scattered in different sources,which makes the task of gatheringinformation about dissimilar FSW of Al?Cu *** work has been written with an aim to provide all pertinentinformation related to dissimilar FSW of Al?Cu at one place to ease the problems of *** comprehensively covers andsummarizes the topics such as the effect of tool design and geometry,FSW process parameters,FSW strategies on mechanicalproperties,microstructure and formation of defects during dissimilar FSW of Al?*** addition,it also presents and discussesseveral variants of dissimilar FSW of Al?***,this work not only puts forth major findings of the previous researchers but alsosuggests future recommendations for dissimilar FSW of Al?Cu.

关键词： aluminium copper friction stir welding intermetallic compounds mechanical properties weld nugget zone

Effect of thermo-mechanical processing on microstructure and electrochemical behavior of Ti-Nb-Zr-V new metastable β titanium biomedical alloy

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Transactions of Nonferrous Metals Society of China 2015年第3期25卷 759-769页

作者： Mohsin Talib MOHAMMED zahid a.khan M.GEETHA Department of Mechanical Engineering Faculty of EngineeringKufa University Department of Mechanical Engineering Jamia Millia Islamia Centre for Biomaterials Science and Technology VIT University

The influence of thermo-mechanical processing (TMP) on the microstructure and the electrochemical behavior of new metastableβ alloy Ti?20.6Nb?13.6Zr?0.5V (TNZV) was investigated. The TMP included hot working in belowβ transus, solution heat treatments at the same temperature and different cooling rates in addition to aging. Depending upon the TMP conditions, a wide range of microstructures with varying spatial distributions and morphologies of equiaxed/elongatedα andβ phases were attained, allowing for a wide range of electrochemical properties to be achieved. The corrosion behavior of the studied alloy was evaluated in a Ringer’s solution at 37 °C via open circuit potential?time and potentiodynamic polarization measurements.

关键词： titanium alloy thermo-mechanical processing biomedical application microstructure electrochemical behavior corrosion

Review on underwater friction stir welding: A variant of friction stir welding with great potential of improving joint properties

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Transactions of Nonferrous Metals Society of China 2018年第2期28卷 193-219页

作者： Mohd.Atif WAHID zahid a.khan Arshad Noor SIDDIQUEE Department of Mechanical Engineering Jamia Millia Islamia

Friction stir welding（FSW） is a solid-state welding process which is capable of joining materials which are relatively difficult to be welded by fusion welding process. Further, this process is highly energy-efficient and environmental-friendly as compared to the fusion welding. Despite several advantages of FSW over fusion welding, the thermal cycles involved in FSW cause softening in joints generally in heat-treatable aluminum alloys（AAs） due to the dissolution or coarsening of the strengthening precipitates leading to decrease in mechanical properties. Underwater friction stir welding（UFSW） can be a process of choice to overcome these limitations. This process is suitable for alloys that are sensitive to heating during the welding and is widely used for heat-treatable AAs. The purpose of this article is to provide comprehensive literature review on current status and development of UFSW and its importance in comparison to FSW with an aim to discuss and summarize different aspects of UFSW. Specific attention is given to basic principle including material flow, temperature generation, process parameters, microstructure and mechanical properties. From the review, it is concluded that UFSW is an improved method compared with FSW for improving joint strength. Academicians, researchers and practitioners would be benefitted from this article as it compiles significantly important knowledge pertaining to UFSW.

关键词： aluminum friction stir welding fusion welding mechanical properties microstructure underwater friction stir welding

Analysis of defects in clean fabrication process of friction stir welding

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Transactions of Nonferrous Metals Society of China 2017年第7期27卷 1507-1516页

作者： Noor Zaman khan zahid a.khan Arshad Noor SIDDIQUEE Abdulrahman M.AL-AHMARI Mustufa H.ABIDI Department of Mechanical Engineering Jamia Millia Islamia (A Central University) New Delhi PIN-110025 India Princess Fatima Alnijris Research Chair for Advanced Manufacturing Technology Advanced Manufacturing Institute King Saud University Riyadh-11421 Saudi Arabia

Striving for cleaner production is a sought-after manufacturing *** stir welding(FSW)is a joiningtechnique with par excellence and far less invasive to the environment than even best conventional welding *** is energyefficient and free from consumables,affluent and *** is,thus,accepted as a clean welding process that can produceacceptable quality *** suffers from some major challenges of defects of its own kind that subject the process open toimprovements so as to prove itself a reliable production *** study presents a holistic characterization of defects commonlyfound in FSW *** finding of the present study reveals that most defects are caused by inadequate heat generation,impropermaterial movement around the pin and inadequate material consolidation behind the *** amount of heat generation andmaterial stirring depends on several FSW parameters which may lead to the defect formation,if not selected *** resultsreported in this work are derived from sound literature support and *** are made in the form ofcharacteristics of defects such as likelihood of their location,main responsible parameters along with the recommendations forminimizing them.

关键词： clean welding process friction stir welding defect process parameter

A Multi-Hop Moving Zone(MMZ) Clustering Scheme Based on Cellular-V2X

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China Communications 2018年第7期15卷 55-66页

作者： zahid khan Pingzhi Fan Key Laboratory of Information Coding and Transmission School of Information Science and TechnologySouthwest Jiaotong University

A clustering scheme based on pure V2V communications has two prominent issues i.e. broadcast storm and network disconnection. The application of the fifth generation(5G) technology to vehicular networks is an optimal choice due to its wide coverage and low latency features. In this paper, a Multihop Moving Zone(MMZ) clustering scheme is proposed by combining IEEE 802.11p with the 3rd Generation Partnership Project(3GPP) 5G cellular technology. In MMZ, vehicles are clustered up-to three hops using V2V communications based on IEEE 802.11 p aiming to reduce excessive cellular hand-off cost. While the zonal heads(ZHs) i.e. cluster heads(CHs) are selected by cellular-V2X(C-V2X) on the basis of multi-metrics i.e. relative speed, distance and link life time(LLT). The main goal of MMZ is to form stable clusters achieving high packet delivery and low latency. The simulation results using ns3 show that, 5G wide range technology significantly improves the stability of MMZ in term of ZH duration and change rate. The average Data Packet Delivery Ratio(DPDR) and E2E latency are also improved as compared to the existing clustering schemes.

关键词： clustering 3GPP 5G cluster head stable clusters reliability and latency

Robust Half-Metallicity and Magnetic Properties of Cubic Perovskite CaFeO_(3)

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Chinese Physics Letters 2013年第4期30卷 192-196页

作者： zahid Ali Iftikhar Ahmad Banaras khan Imad khan Materials Modeling Center Department of PhysicsUniversity of MalakandChakdaraDir(L)Pakistan Department of Physics Hazara UniversityMansehraPakistan

Theoretical studies of the cubic perovskite CaFeO3 are performed using the full potential linearized augmented plane-wave method with GGA+*** calculated structural parameters are consistent with the experimental *** tolerance factor reveals the cubic phase of the *** spin polarized electronic band structures and densities of states as well as the integer value of the magnetic moment of the unit cell(4μB)demonstrate that CaFeO_(3)is half *** in CaFeO_(3)is due to Fe^(+4)–O^(2)–Fe^(+4)superexchange *** robust properties of the compound show that with their compression up to a certain critical lattice constant,known as the robust transition lattice constant,an abrupt change in the electronic and magnetic properties occurs;the compounds lose their integer magnetic moment and become metallic.

关键词： integer cubic magnetic

Spherical Gravitational Collapse in f(R) Gravity with Linear Equation of State

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Communications in Theoretical Physics 2018年第8期69卷 185-189页

作者： zahid Ahmad Hassan Shah Suhail khan Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics University of Peshawar

In a paper [Gen. Relativ. Gravit. 48(2016) 57] Chakrabarti and Banerjee investigated perfect fluid collapse in f(R) gravity model and claimed that such a collapse is possible. In this paper we show that without the assumption of dark energy it is not possible that perfect fluid spherical gravitational collapse will occur. We have solved the field equations by assuming linear equation of state(p = ωμ) in metric f(R) gravity with ω =-1. It is shown that Chakrabarti and Banerjee reached to false conclusion as they derived wrong field equations. We have also discussed formation of apparent horizon and singularity.

关键词： gravitational collapse matching conditions dark energy apparent horizon

A split target detection and tracking algorithm for ballistic missile tracking during the re-entry phase

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Defence Technology（防务技术） 2020年第6期16卷 1142-1150页

作者： Muhammad Asad Sumair khan Ihsanullah zahid Mehmood Yifang Shi Sufyan Ali Memon Uzair khan Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusPakistan Department of Computer Science COMSATS University IslamabadAbbottabad CampusPakistan Electrical Engineering Department Indus UniversityKarachiPakistan Department of Automation Hangzhou Dianzi UniversityXiasha Higher Education Zone2nd StreetHangzhou310018China

In the re-entry phase of a ballistic missile,decoys can be deployed as a mean to overburden enemy *** results in a single track being split into multiple *** of these track-lets is a critical task as any miss in the tracking procedure can become a cause of a major *** tracking process becomes more complicated in the presence of *** low detection rate is one of the factors that may contribute to increasing the difficulty level in terms of tracking in the cluttered *** work introduces a new algorithm for the split event detection and target tracking under the framework of the joint integrated probabilistic data association(JIPDA)*** proposed algorithm is termed as split event-JIPDA(SE-JIPDA).This work establishes the mathematical foundation for the split target detection and tracking *** performance analysis is made under different simulation conditions to provide a clear insight into the merits of the proposed *** performance parameters in these simulations are the root mean square error(RMSE),confirmed true track rate(CTTR)and confirmed split true track rate(CSTTR).

关键词： Split event probability JIPDA Data association Ballistic missile Estimation

Investigation of E-H mode transition in magnetic-pole-enhanced inductively coupled neon-argon mixture plasma

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Plasma Science and Technology 2020年第6期22卷 110-119页

作者： zahid Iqbal KHATTAK Abdul Waheed khan Faiq JAN Muhammad SHAFIQ Department of Physics Quaid-i-Azam University45320 IslamabadPakistan Department of Physics Gomal University29050 D.I.KhanPakistan Department of Physics Govt.Post Graduate College Nowshera24100 NowsheraPakistan 不详

In this paper,E-H mode transition in magnetic-pole-enhanced inductively coupled neon-argon mixture plasma is investigated in terms of fundamental plasma parameters as a function of argon fraction(0%-100%),operating pressure(1 Pa,5 Pa,10 Pa and 50 Pa),and radio frequency(RF)power(5-100 W).An RF compensated Langmuir probe and optical emission spectroscopy are used for the diagnostics of the plasma under *** to the lower ionization potential and higher collision cross-section of argon,when its fraction in the discharge is increased,the mode transition occurs at lower RF power;*** 0%argon and1 Pa pressure,the threshold power of the E-H mode transition is 65 W,which reduces to 20 W when the argon fraction is *** electron density increases with the argon fraction at afixed pressure,whereas the temperature decreases with the argon *** relaxation length of the low-energy electrons increases,and decreases for high-energy electrons with argon fraction,due to the Ramseur ***,the relaxation length of both groups of electrons decreases with pressure due to reduction in the mean free *** electron energy probability function(EEPF)profiles are non-Maxwellian in E-mode,attributable to the nonlocal electron kinetics in this mode;however,they evolve to Maxwellian distribution when the discharge transforms to H-mode due to lower electron temperature and higher electron density in *** tail of the measured EEPFs is found to deplete in both E-and H-modes when the argon fraction in the discharge is increased,because argon has a much lower excitation potential(11.5 eV)than neon(16.6 eV).

关键词： Ne-Ar MaPE-ICP Langmuir probe OES electron temperature electron density mode transition