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Communications in Theoretical Physics 2018年第8期69卷 239-248页

作者： Z.Iqbal Ehtsham Azhar E.N.Maraj Zaffar mehmood Department of Mathematics Faculty of Sciences HITEC University

Presence of external electrical field plays a vital role in heat transfer and fluid flow phenomena. Keeping this in view present article is a numerical investigation of stagnation point flow of water based nanoparticles suspended fluid under the influence of induced magnetic field. A detailed comparative analysis has been performed by considering Copper and Titanium dioxide nanoparticles. Utilization of similarity analysis leads to a simplified system of coupled nonlinear differential equations, which has been tackled numerically by means of shooting technique followed by Runge-Kutta of order 5. The solutions are computed correct up to 6 decimal places. Influence of pertinent parameters is examined for fluid flow, induced magnetic field, and temperature profile. One of the key findings includes that magnetic parameter plays a vital role in directing fluid flow and lowering temperature profile. Moreover, it is concluded that Cu-water based nanofluid high thermal conductivity contributes in enhancing heat transfer efficiently.

关键词： water based fluid instigated magnetic region nanoscale particles Copper and titanium dioxide stagnation point flow numerical solutions

Magnetohydrodynamic flow and heat transfer impact on ZnO-SAE50 nanolubricant flow over an inclined rotating disk

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Journal of Central South University 2019年第5期26卷 1146-1160页

作者： NAYAK M K mehmood Rashid MAKINDE O D MAHIAN O CHAMKHA Ali J Department of Physics Radhakrishna Institute of Technology and EngineeringBhubaneswar-752057India Department of Mathematics Faculty of Natural ScienceHITEC University Taxila-47070Pakistan Faculty of Military Science Stellenbosch UniversityPrivate Bag X2Saldanha 7395South Africa Center for Advanced Technologies Ferdowsi University of MashhadMashhadIran School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Mechanical Engineering Department Prince Sultan Endowment for Energy and EnvironmentPrince Mohammad Bin Fahd UniversityAl-Khobar 31952Saudi Arabia RAK Research and Innovation Center American University of Ras Al KhaimahP.O.Box 10021Ras Al KhaimahUnited Arab Emirates

The present article has been fine-tuned with the investigation of mixed convection Darcy-Forchheimer flow of ZnO-SAE50 oil nanolubricant over an inclined rotating disk under the influence of uniform applied magnetic field applied to various *** current study has been enriched with additional consideration of slip flow,thermal radiation,viscous dissipation,Joulian dissipation and internal *** view of augmentation of thermal conductivity of nanolubricant,a new micro-nano-convection model namely Patel model has been *** specialty of this model involves the effects of specific surface area and nano-convection due to Brownian motion of nanoparticles,kinetic theory based micro-convection,liquid layering and particle *** transformed governing equations have been solved numerically by using Runge-Kutta-Fehlberg *** analysis of the present study has shown that applied magnetic field,porosity of the medium,velocity slip and inertia coefficient account for the slowing down of radial as well as tangential flow of ZnO-SAE50 oil nanolubricant,thereby leading to an improvement in velocity and thermal boundary layers.

关键词： ZnO-SAE50 nanofluid Darcy-Forchheimer MHD flow thermal radiation velocity slip viscous dissipation internal heating

Coupled Electromagnetic-thermal Analysis of Segmented PM Consequent Pole Flux Switching Machine

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Chinese Journal of Electrical Engineering 2021年第2期7卷 50-60页

作者： Wasiq Ullah faisal Khan Muhammad Umair Erwan Sulaiman Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusAbbottabad 22060Pakistan Department of Electrical Power Engineering Universiti Tun Hussein Onn MalaysiaParit Raja 86400Malaysia

Compact stator structure of flux switching machines(FSMs)encompassing both permanent magnets(PMs)and armature winding slots(AWS)attract research interest whenever high power and density are the basic ***,it also results in temperature rises owing to heat generation by electromagnetic power losses degrading the electromagnetic performance and affecting machine *** this study,a segmented permanent magnet(SPM)consequent pole FSM(SPM-CPFSM)is developed,which provides a stator cooling channel(duct)for improved heat dissipation to avoid demagnetization of PM as well as ***,this study investigates detailed electromagnetic performance analysis and prediction of temperature variation in various machine parts owing to the heat generated by iron,copper,and magnet eddy current losses utilizing coupled electromagnetic-thermal analysis accounting for magnetic flux density *** comparison with the 2D analysis,the developed 3D coupled-field analysis more accurately predicts electromagnetic performance and temperature *** reveals that a cooling duct at the stator significantly assists in stator heat dissipation in the axial direction ensuring a safe operating condition of the PMs as well as machine parts to avoid overheating.

关键词： AC machines coupled field consequent pole permanent magnet loss analysis thermal analysis

Sentiment Analysis in Social Media for Competitive Environment Using Content Analysis

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Computers, Materials & Continua 2022年第6期71卷 5603-5618页

作者： Shahid mehmood Imran Ahmad Muhammad Adnan Khan Faheem Khan T.Whangbo Riphah School of Computing&Innovation Faculty of ComputingRiphah International University Lahore CampusLahore54000Pakistan Pattern Recognition and Machine Learning Lab Department of SoftwareGachon UniversitySeongnamGyeonggido13120Korea Department of Computer Engineering Gachon UniversitySeongnam13557Korea

Education sector has witnessed several changes in the recent *** changes have forced private universities into fierce competition with each other to get more students *** competition has resulted in the adoption of marketing practices by private universities similar to commercial *** get competitive gain,universities must observe and examine the students’feedback on their own social media sites along with the social media sites of their *** study presents a novel framework which integrates numerous analytical approaches including statistical analysis,sentiment analysis,and text mining to accomplish a competitive analysis of social media sites of the *** techniques enable local universities to utilize social media for the identification of the most-discussed topics by students as well as based on the most unfavorable comments received,major areas for improvement.A comprehensive case study was conducted utilizing the proposed framework for competitive analysis of few top ranked international universities as well as local private universities in Lahore *** results show that diversity of shared content,frequency of posts,and schedule of updates,are the key areas for improvement for the local *** on the competitive intelligence gained several recommendations are included in this paper that would enable local universities generally and Riphah international university(RIU)Lahore specifically to promote their brand and increase their attractiveness for potential students using social media and launch successful marketing campaigns targeting a large number of audiences at significantly reduced cost resulting in an increased number of enrolments.

关键词： Social media higher education sentiment analysis content analysis competitive analysis text mining

First COVID-19 related death in Pakistan in a patient with a travel history in Saudi Arabia

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Asian Pacific Journal of Tropical Medicine 2020年第8期13卷 375-377页

作者： Rooh Ullah Muhammad Suleman Rana mehmood Qadir Muhammad Usman Department of Microbiology Quaid-i-Azam UniversityIslamabadPakistan Department of Virology National Institute of HealthIslamabadPakistan Atta ur Rahman School of Applied Biosciences National University of Science and TechnologyIslamabadPakistan

Rationale: Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2) has been recognized as highly pathogenic. The current pandemic of SARS-CoV-2 has been spread globally and infected more than 200 countries. Patient concerns: We report the first confirmed fatal case of COVID-19 in Pakistan. A 50-year-old man returned from Saudi Arabia on March 09, 2020 and presented with cough, fever, malaise, poor appetite and difficulty in breathing to the Pulmonologist at District Headquarter Hospital Mardan. Diagnosis: The patient was initially diagnosed as COVID-19 suspected case. A oropharyngeal swab sample was positive by realtime RT-PCR tests. Lessons: This report highlights the importance of close coordination between clinicians and public health authorities as well as the importance of early laboratory-based confirmation of COVID-19 cases.

关键词： COVID-19 SARS-CoV-2 Pakistan

An Ensemble Learning Based Approach for Detecting and Tracking COVID19 Rumors

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Computers, Materials & Continua 2022年第1期70卷 1721-1747页

作者： Sultan Noman Qasem Mohammed Al-Sarem faisal Saeed Computer Science Department College of Computer and Information SciencesAl Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia Computer Science Department Faculty of Applied ScienceTaiz UniversityTaiz6803Yemen College of Computer Science and Engineering Taibah UniversityMedinaSaudi Arabia Information System Department Saba’a Region UniversityMareebYemen

Rumors regarding epidemic diseases such as COVID 19,medicines and treatments,diagnostic methods and public emergencies can have harmful impacts on health and political,social and other aspects of people’s lives,especially during emergency situations and health *** huge amounts of content being posted to social media every second during these situations,it becomes very difficult to detect fake news(rumors)that poses threats to the stability and sustainability of the healthcare sector.A rumor is defined as a statement for which truthfulness has not been *** COVID 19,people found difficulty in obtaining the most truthful news easily because of the huge amount of unverified information on social *** methods have been applied for detecting rumors and tracking their sources for COVID 19-related ***,very few studies have been conducted for this purpose for the Arabic language,which has unique ***,this paper proposes a comprehensive approach which includes two phases:detection and *** the detection phase of the study carried out,several standalone and ensemble machine learning methods were applied on the Arcov-19 dataset.A new detection model was used which combined two models:The Genetic Algorithm Based Support Vector Machine(that works on users’and tweets’features)and the stacking ensemble method(that works on tweets’texts).In the tracking phase,several similarity-based techniques were used to obtain the top 1%of similar tweets to a target tweet/post,which helped to find the source of the *** experiments showed interesting results in terms of accuracy,precision,recall and F1-Score for rumor detection(the accuracy reached 92.63%),and showed interesting findings in the tracking phase,in terms of ROUGE L precision,recall and F1-Score for similarity techniques.

关键词： Rumor detection rumor tracking similarity techniques COVID-19 social media analytics

Smart Piezo-Resistive Sensing and Experience Based Control for Soft Robot Grasping

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Smart Piezo-Resistive Sensing and Experience Based Control f...

作者： Jawad mehmood Butt 上海交通大学

学位级别：硕士

软机器人由于具有极高自由度,在形状适应和复杂运动等任务方面具有极大应用潜力。这些自由度为软机器人在开环控制中执行相应任务提供了足够的空间,与刚性机器人相比更适合在复杂非结构环境中作业。这些人工软机器人主要是从人类身上获... 详细信息

软机器人由于具有极高自由度,在形状适应和复杂运动等任务方面具有极大应用潜力。这些自由度为软机器人在开环控制中执行相应任务提供了足够的空间,与刚性机器人相比更适合在复杂非结构环境中作业。这些人工软机器人主要是从人类身上获得灵感,但相对而言,并没有表现出智能嵌入式传感和决策这两个最重要的生物灵感支柱,因此,本文的工作使软机器人朝着决策和智能传感迈出了一步。触觉感知和位置反馈使机器人能够更好地理解现实世界中的相互作用。在其中,最重要的一点是,感知要求主体和客体以定性的方式处理。针对这一问题,在论文的第一部分,我们研究了二维软机器人,即作为感知主体的软体夹持器和作为感知对象的可变刚度,不同重量和几何形状的目标夹持物。与能够提供触觉和位置反馈的人手相比,软机器人操作手难以被赋予相似的智能性,这种滞后限制了软件抓手在开环控制域中应用。在本文中,我们提出了适用于闭环控制应用一种柔软的操作手设计方案与控制方法。我们设计的索驱动软夹持器能够提供触觉和位置反馈,并满足触觉和位置感知的标准及其在闭环控制任务中的应用。本文提出的传感器在材料,设计和制造方面相较于现有工作具有一定的创新。在以往的工作中,用于软体操作手上的压力传感器与柔性材料的顺应性不兼容,因此或多或少的限制了执行器的运动,降低软体操作手的灵活性。因此我们设计了一种在软体内部创建压力传感器的方法。该传感器完全用柔性材料制作而成,并且实现了软触觉感知的概念。另一方面,位置传感器同样使用柔性材料制造,相比于同类型位置传感器,我们的设计满足了微型化的要求;除此外,相较于一般的位置传感器设计仅适用于软机器人的离散运动,本文提出的传感器同样适用于软机器人连续移动信号的采集。为了证明传感器性能,我们进行传感器特性测试和抓取实验,证实了该传感器在抓取任务期间可提供重复且高精度测量结果。文章的第二部分侧重于开发基于经验的最佳控制策略。该策略基于决策的概念。由于软体操作手的抓握行为是随机的而不是确定性的(这是因为软体操作手额外的柔顺性以及目标物体几何形状,变形因子和重量参数的不确定性造成的),这使得非结构化环境中的随机抓握任务产生了概率效应。针对这个问题,我们提出了一种创新性的基于Q学习经验策略,即将抓取任务分割为多个事件,然后通过最小化成本函数进行运动策略的优化。软体操作手行为模型和抓取模型是通过概率事件而建模的,是抓取策略的主要组成部分。建模中所使用的数据由配有位置反馈的软体操作手提供。该策略的输出是在控制任务中软机器人学习到的成功抓取到可变形目标物体的权重。除此之外,数据集通过增加不同重量和刚度的目标对象来避免欠拟合并使得该策略变得高效。在该部分的最后,我们通过对所提方法的定性分析以证明其优越性。

关键词：软式机器人抓手软压力传感器柔性位置传感器基于织物的位置传感器机器人学中的Q-学习本体感觉机器人抓取基于行为的控制概率控制数据驱动机器人强化学习

Performance behaviour of elliptical-bore journal bearings lubricated with solid granular particulates

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Particuology 2016年第4期14卷 51-60页

作者： faisal Rahmani Jayanta K. Dutt Raj K. Pandey Department of Mechanical Engineering Indian Institute of Technology Delhi New Delhi 110016 India

Journal bearings operating in hot environments and at high temperatures experience accelerated degra- dation of lubricating oils. In such situations, dry granular particulates have emerged as potential media for providing lubrication in journal bearings in place of lubricating oils. Granular particulates do not degrade thermally, even at considerably high temperatures. This work explores the static and dynamic perfor- mance characteristics of elliptical-bore journal bearings lubricated with granular particulates. It is found that a bearing lubricated with a larger size （2 μm） particles offers better performance compared with that using smaller size （1μm） particles. Bore ellipticity reduces the load-carrying capacity and increases side leakage and the coefficient of friction; however, rotor stability is marginally improved at low eccentricity ratios （〈0.6）, followed by significant improvement at high eccentricity ratios （〉0.6）.

关键词： Particulate Journal bearing Grain size Rigid rotor stability Hydrodynamic lubrication

A Machine Learning Based Algorithm to Process Partial Shading Effects in PV Arrays

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Computers, Materials & Continua 2021年第7期68卷 29-43页

作者： Kamran Sadiq Awan Tahir Mahmood Mohammad Shorfuzzaman Rashid Ali Raja Majid mehmood Department of Electrical Engineering University of Engineering and TechnologyTaxila47080Pakistan Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia School of Intelligent Mechatronics Engineering Sejong UniversityKorea Department of Information and Communication Technology School of Electrical and Computer EngineeringXiamen University MalaysiaSepang43900Malaysia

Solar energy is a widely used type of renewable *** arrays are used to harvest solar *** major goal,in harvesting the maximum possible power,is to operate the system at its maximum power point(MPP).If the irradiation conditions are uniform,the P-V curve of the PV array has only one peak that is called its *** when the irradiation conditions are non-uniform,the P-V curve has multiple *** peak represents an MPP for a specific irradiation *** highest of all the peaks is called Global Maximum Power Point(GMPP).Under uniform irradiation conditions,there is zero or no partial *** the changing irradiance causes a shading effect which is called Partial *** conventional and soft computing techniques have been in use to harvest solar *** techniques perform well under uniform and weak shading conditions but fail when shading conditions are *** this paper,a new method is proposed which uses Machine Learning based algorithm called Opposition-Based-Learning(OBL)to deal with partial shading *** studies on different cases of partial shading have proven this technique effective in attaining MPP.

关键词： Maximum power point tracking flower pollination algorithm opposition-based-learning flower pollination algorithm hybridized with opposition based learning

Improvements in mechanical, corrosion, and biocompatibility properties of Mg–Zr–Sr–Dy alloys via extrusion for biodegradable implant applications

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Journal of Magnesium and Alloys 2023年第10期11卷 3840-3865页

作者： faisal Kiani Jixing Lin Khurram Munir Cuie Wen Yuncang Li School of Engineering RMIT UniversityMelbourneVictoria 3001Australia School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027China

In this study,extrusion was performed on Mg-Zr-Sr-Dy alloys for improving their mechanical,corrosion,and biocompatibility *** of extrusion and alloying elements on the microstructural characteristics,tensile and compressive strengths,corrosion behavior,and biocompatibility were *** Mg-Zr-Sr-Dy alloys were composed of an α-Mg matrix containing {10■2} extension twins and secondary phases of intermetallic compounds Mg_(17)Sr_(2) and Mg_(2)*** of basal and rare earth(RE) textures was observed in the extruded alloys and an increase in Dy content to 2 wt.% resulted in texture randomization and strengthening of the RE component,mainly due to particle-stimulated nucleation and a change from discontinuous dynamic recrystallization to continuous dynamic recrystallization,which also led to an improved tension-compression yield asymmetry of *** of the alloys significantly enhanced their tensile and compressive properties due to improved distribution of alloying elements and formation of *** rates tested by hydrogen evolution testing,potentiodynamic polarization,and electrical impedance spectroscopy showed similar trends for each composition,and the lowest corrosion rate of 3.37 mmy^(-1) was observed for the Mg-1Zr-0.5Sr-1Dy in the potentiodynamic polarization ***_(2)O_(3) was observed in the inner layers of the Mg(OH)_(2) protective films,whose protective efficacy was confirmed by charge-transfer and film resistances.A comparison among the minimum CRs observed in this study and previously studied as-cast Mg-Zr-Sr-Dy and extruded Mg-Zr-Sr alloys,demonstrates that both the extrusion process and addition of Dy in Mg-Zr-Sr improved the ***,extruded Mg-Zr-Sr-Dy alloys showed improved cell viability and adhesion of human osteoblast-like SaOS2 cells due to increased corrosion resistance and enhanced Sr distribution within the Mg matrix.

关键词： Corrosion Microstructure mechanical properties Cytotoxicity Mg–Zr–Sr–Dy alloy