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Defence Technology（防务技术） 2017年第2期13卷 86-91页

作者： Sandeep Rathee Sachin Maheshwari arshad Noor Siddiquee Manu Srivastava Division of Manufacturing Processes and Automation Engineering(MPAE) Netaji Subhas Institute of Technology Department of Mechanical Engineering Jamia Millia Islamia A Central University

Aluminium matrix surface composites are gaining alluring role especially in aerospace, defence, and marine industries. Friction stir processing(FSP) is a promising novel solid state technique for surface composites fabrication. In this study, AA6061/SiC surface composites were fabricated and the effect of tool plunge depth on pattern of reinforcement particles dispersion in metal matrix was investigated. Six varying tool plunge depths were chosen at constant levels of shoulder diameter and tool tilt angle to observe the exclusive effect of plunge variation. Process parameters chosen for the experimentation are speed of rotation, travel speed and tool tilt angle which were taken as 1400 rpm, 40 mm/min, and 2.5 °respectively. Macro and the microstructural study were performed using stereo zoom and optical microscope respectively. Results reflected that lower plunge depth levels lead to insufficient heat generation and cavity formation towards the stir zone center. On the other hand, higher levels of plunge depth result in ejection of reinforcement particles and even sticking of material to tool shoulder. Thus, an optimal plunge depth is needed in developing defect free surface composites.

关键词： Metal matrix composites Friction stir processing Tool plunge depth Microstructural characterization

Magnetic Field-induced Enhancement of Phase Change Heat Transfer via Biomimetic Porous Structure for Solar-thermal Energy Storage

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Journal of Bionic Engineering 2021年第5期18卷 1215-1224页

作者： Juan Li Zhangyu Zhu Adeel arshad Shuai Zhang Lei Shi Yuying Yan School of Mechanical and Electrical Engineering Nanjing Forestry UniversityNanjing 210037People's Republic of China Fluids and Thermal Engineering Research Group Faculty of EngineeringUniversity of NottinghamNottingham NG72RDUK School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001People's Republic of China

Multifunctional phase change composites are in great demand for all kinds of industrial technologies and applications,which have both superior latent heat capacity and excellent solar-thermal conversion *** this research,biomimetic phase change composites are made by inspired by natural systems,successfully getting the high thermal conductivity of carbon foam and magnetism of composites together,to establish a novel solar-thermal energy storage *** morphology and the thermal characteristics of biomimetic phase change composites have been *** results showed that the maximum storage efficiency of the biomimetic phase change materials increased by 56.3%compared to that of the based materials,and it can further be improved by the application of magnetic *** the heat transfer process of solarthermal conversion and energy storage in biomimetic porous structure under the external physical fields has been explained by ***,the magnetic field-induced method applied in this research has better solar-thermal energy storage characteristics within a porous structure by dynamically controlling the magnetism,which has potential uses for various sustainable applications,including waste-heat recovery,energy conservation in building,and solar-thermal energy storage.

关键词： Bionic porous structure Solar-thermal conversion Thermal energy storage Phase change materials Magnetic nanoparticles

Snowmelt runoff prediction under changing climate in the Himalayan cryosphere: A case of Gilgit River Basin

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Geoscience Frontiers 2017年第5期8卷 941-949页

作者： Muhammad Adnan Ghulam Nabi Muhammad Saleem Poomee arshad Ashraf Climate Change Alternate Energy and Water Resources Institute (CAEWRI) National Agricultural Research Center Park Road Chakshahzad Islamabad Pakistan Center of Excellence in Water Resources (CEWR) Lahore Pakistan

There are serious concerns of rise in temperatures over snowy and glacierized Himalayan region that may eventually affect future river flows of Indus river system. It is therefore necessary to predict snow and glacier melt runoff to manage future water resource of Upper Indus Basin(UIB). The snowmelt runoff model(SRM) coupled with MODIS remote sensing data was employed in this study to predict daily discharges of Gilgit River in the Karakoram Range. The SRM was calibrated successfully and then simulation was made over four years i.e. 2007, 2008, 2009 and 2010 achieving coefficient of model efficiency of 0.96, 0.86, 0.9 and 0.94 respectively. The scenarios of precipitation and mean temperature developed from regional climate model PRECIS were used in SRM model to predict future flows of Gilgit River. The increase of 3 C in mean annual temperature by the end of 21 th century may result in increase of 35-40% in Gilgit River flows. The expected increase in the surface runoff from the snow and glacier melt demands better water conservation and management for irrigation and hydel-power generation in the Indus basin in future.

关键词： Snowmelt runoff model Climate change Gilgit River Himalayan region

An Optimal DPM Based Energy-Aware Task Scheduling for Performance Enhancement in Embedded MPSoC

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Computers, Materials & Continua 2023年第1期74卷 2097-2113页

作者： Hamayun Khan Irfan Ud Din arshad Ali Mohammad Husain Department of Electrical Engineering Faculty of Engineering&Technology Superior University Lahore54000Pakistan Department of Computer Science Faculty of Computer Science&IT Superior University Lahore54000Pakistan Faculty of Computer and Information Systems Islamic University of MadinahAl Madinah Al Munawarah42351Saudi Arabia

Minimizing the energy consumption to increase the life span and performance of multiprocessor system on chip(MPSoC)has become an integral chip design issue for multiprocessor *** performance measurement of computational systems is changing with the advancement in *** to shrinking and smaller chip size power densities onchip are increasing rapidly that increasing chip temperature in multi-core embedded *** operating speed of the device decreases when power consumption reaches a threshold that causes a delay in complementary metal oxide semiconductor(CMOS)circuits because high on-chip temperature adversely affects the life span of the *** this paper an energy-aware dynamic power management technique based on energy aware earliest deadline first(EA-EDF)scheduling is proposed for improving the performance and reliability by reducing energy and power consumption in the system on chip(SOC).Dynamic power management(DPM)enables MPSOC to reduce power and energy consumption by adopting a suitable core configuration for task *** migration avoids peak temperature values in the multicore *** utilization factor(ui)on central processing unit(CPU)core consumes more energy and increases the temperature *** technique switches the core bymigrating such task to a core that has less temperature and is in a low power *** proposed EA-EDF scheduling technique migrates load on different cores to attain stability in temperature among multiple cores of the CPU and optimized the duration of the idle and sleep periods to enable the low-temperature *** effectiveness of the EA-EDF approach reduces the utilization and energy consumption compared to other existing methods and *** simulation results show the improvement in performance by optimizing 4.8%on u_(i) 9%,16%,23%and 25%at 520 MHz operating frequency as compared to other energy-aware techniques for MPSoCs when the least number of tasks is in running state and can

关键词： Dynamic power management dynamic voltage&frequency scaling dynamic thermal management multiprocessor system on chip complementary metal oxide semiconductor reliability

Diffusion of Six-Atom Cu Islands on Cu(111)and Ag(111)

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Chinese Physics Letters 2011年第5期28卷 99-102页

作者： Sardar Sikandar Hayat I.Ahmad M.arshad Choudhry Department of Physics and Astronomy Hazara UniversityMansehra 23100Pakistan Department of Physics The Islamia University of BahawalpurBahawalpur 63120Pakistan

Diffusion of Cu hexamer islands on Cu(111)and Ag(111)is studied using a molecular dynamics simulation technique with many-body potentials obtained from the embedded atom *** are carried out at temperatures 300,500 and 700 K,showing that shape-changing multiple-atom processes are more helpful for the diffusion rather than concerted motion of *** plots of the diffusion coefficients provide effective energy barrier values of 161.29±5 meV for Cu(111)and 179.34±5 meV for Ag(111)*** 700K,one pop-up atom among island atoms is observed with correlative changes in the position and shape of the lower-layer adatoms.

关键词： Cu(111) method Diffusion

Structural and spectroscopic analysis of wurtzite（ZnO）1-x（Sb2O3）x composite semiconductor

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Progress in Natural Science:Materials International 2015年第2期25卷 131-136页

作者： Hafeez ullah Amjid Iqbal M. Zakria arshad Mahmood University of Trento Department of Physics Via Sommarive 14 Povo 38123 Trento Italy Center for Materials and Microsystems Fondazione Bruno Kessler Via Sommarive 18 Povo 38123 Trento Italy National Institute of Lasers and Optronics (NILOP) Nilore Islamabad Pakistan

The structural, vibrational and impedance analysis for(Zn O)1 x(Sb2O3)xcomposite synthesized by solid state reaction technique were carried out in the present investigation. X-ray diffraction(XRD) study showed that(Zn O)1 x(Sb2O3)xcomposite has hexagonal(wurtzite) crystal structure. Variation in lattice constants with Sb-doping indicated the proper incorporation of Sb dopant in Zn O host matrix. The results of Raman spectroscopy test suggested the signature of E2(high) and E1(TO) Raman modes, and verified the wurtzite structure of(Zn O)1 x(Sb2O3)x composite. Two additional phonon bands(671, 712) cm 1appeared in Raman spectra of composite samples due to the existence of the lattice defects caused by Sb doping or may be other intrinsic lattice defects formed during the synthesis of(Zn O)1 x(Sb2O3)xcomposite. The frequency dependent on the electrical characteristics, such as, impedance(Z), dielectric constant(ε) and AC conductivity(σ) have been studied in a range of frequencies for different Sb concentration at room temperature. The electrical measurement results showed that the impedance increased with Sb dopant concentration, while dielectric constant and AC conductivity decreased with Sb dopant concentration.

关键词： (Zn O)1 x(Sb2O3)x Semiconductors XRD Raman spectroscopy Impedance spectroscopy

Structural and optical properties of thermally reduced graphene oxide for energy devices

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Chinese Physics B 2017年第8期26卷 346-352页

作者： Ayesha Jamil Faiza Mustafa Samia Aslam Usman arshad Muhammad Ashfaq Ahmad Department of Physics COMSATS Institute of Information TechnologyLahore 54000Pakistan

Natural intercalation of the graphite oxide, obtained as a product of Hummer＇s method, via ultra-sonication of water dispersed graphite oxide has been carried out to obtain graphene oxide（GO） and thermally reduced graphene oxide（RGO）.Here we report the effect of metallic nitrate on the oxidation properties of graphite and then formation of metallic oxide（MO） composites with GO and RGO for the first time. We observed a change in the efficiency of the oxidation process as we replaced the conventionally used sodium nitrate with that of nickel nitrate Ni（NO_3）_2, cadmium nitrate Cd（NO_3）_2,and zinc nitrate Zn（NO_3）_2. The structural properties were investigated by x-ray diffraction and observed the successful formation of composite of MO–GO and MO–RGO（M = Zn, Cd, Ni）. We sought to study the effect on the oxidation process through optical characterization via UV-Vis spectroscopy and Fourier Transform Infrared（FTIR） ***, Thermo Gravimetric Analysis（TGA） was carried out to confirm 〉 90% weight loss in each process thus proving the reliability of the oxidation cycles. We have found that the nature of the oxidation process of graphite powder and its optical and electrochemical characteristics can be tuned by replacing the sodium nitrate（NaNO_3） by other metallic nitrates as Cd（NO_3）_2, Ni（NO_3）_2, and Zn（NO_3）_2. On the basis of obtained results, the synthesized GO and RGO may be expected as a promising material in antibacterial activity and in electrodes fabrication for energy devices such as solar cell, fuel cell,and super capacitors.

关键词： thermal properties of graphene oxide and reduced graphene oxide optical properties structuralproperties fuel cell composite materials

Cloud authorization： exploring techniques and approach towards effective access control framework

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Frontiers of Computer Science 2015年第2期9卷 297-321页

作者： Rahat MASOOD Muhammad Awais SHIBLI Yumna GHAZI Ayesha KANWAL arshad ALI School of Electrical Engineering and Computer Science (SEECS) National University of Sciences and Technology (NUST) Islamabad - 44000 Pakistan

Despite the various attractive features that Cloud has to offer, the rate of Cloud migration is rather slow, pri- marily due to the serious security and privacy issues that exist in the paradigm. One of the main problems in this regard is that of authorization in the Cloud environment, which is the focus of our research. In this paper, we present a systematic analysis of the existing authorization solutions in Cloud and evaluate their effectiveness against well-established industrial standards that conform to the unique access control require- ments in the domain. Our analysis can benefit organizations by helping them decide the best authorization technique for deployment in Cloud; a case study along with simulation re- sults is also presented to illustrate the procedure of using our qualitative analysis for the selection of an appropriate tech- nique, as per Cloud consumer requirements. From the results of this evaluation, we derive the general shortcomings of the extant access control techniques that are keeping them from providing successful authorization and, therefore, widely adopted by the Cloud community. To that end, we enumer- ate the features an ideal access control mechanisms for the Cloud should have, and combine them to suggest the ultimate solution to this major security challenge - access control as a service （ACaaS） for the software as a service （SaaS） layer. We conclude that a meticulous research is needed to incorpo- rate the identified authorization features into a generic ACaaS framework that should be adequate for providing high level of extensibility and security by integrating multiple accesscontrol models.

关键词： authorization access control software as a ser-vice extensible access control markup language identity &access management cloud security

Transforming Hand Drawn Wireframes into Front-End Code with Deep Learning

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Computers, Materials & Continua 2022年第9期72卷 4303-4321页

作者： Saman Riaz Ali arshad Shahab S.Band Amir Mosavi Department of Computer Science National University of TechnologyIslamabad44000Pakistan Department of Computer Science Institute of Space TechnologyIslamabad44000Pakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliu64002YunlinTaiwan Faculty of Civil Engineering Technische Universitat DresdenDresden 01069Germany

The way towards generating a website front end involves a designersettling on an idea for what kind of layout they want the website to have, thenproceeding to plan and implement each aspect one by one until they haveconverted what they initially laid out into its Html front end form, this processcan take a considerable time, especially considering the first draft of the designis traditionally never the final one. This process can take up a large amountof resource real estate, and as we have laid out in this paper, by using a Modelconsisting of various Neural Networks trained on a custom dataset. It can beautomated into assisting designers, allowing them to focus on the other morecomplicated parts of the system they are designing by quickly generating whatwould rather be straightforward busywork. Over the past 20 years, the boomin how much the internet is used and the sheer volume of pages on it demands ahigh level of work and time to create them. For the efficiency of the process, weproposed a multi-model-based architecture on image captioning, consisting ofConvolutional neural network (CNN) and Long short-term memory (LSTM)models. Our proposed approach trained on our custom-made database can beautomated into assisting designers, allowing them to focus on the other morecomplicated part of the system. We trained our model in several batches overa custom-made dataset consisting of over 6300 files and were finally able toachieve a Bilingual Evaluation Understudy (BLEU) score for a batch of 50hand-drawn images at 87.86%.

关键词： Deep learning wireframes front-end low fidelity high fidelity design process html computer vision dsl

Effects of the wall properties on unsteady peristaltic flow of an Eyring-Powell fluid in a three-dimensional rectangular duct

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International Journal of Biomathematics 2015年第6期8卷 185-201页

作者： arshad Riaz S. Nadeem R. Ellahi Department of MathematicsUniversity of Education LahoreJauharabad Campus Pakistan Department of MathematicsQuaid-i-Azam University 45320 Islamabad 44000 Pakistan Department of Mathematics and Statistics FBAS HU Islamabad 44000 Pakistan

In the present investigation, peristaltic flow Powell） has been taken into consideration in of non-Newtonian fluid model （Eyring- a cross-section of three-dimensional rect- angular channel. The flow is taken to be unsteady and incompressible. The observations are made under the limitations of low Reynolds number and long wavelength which helps in reducing the governing equations. The walls of the channel are supposed to be compliant. The obtained equations are nonlinear partial differential equation of second order and have been solved analytically by using series solution technique. The achieved results are then portrayed graphically to see the variation of various emerging parame- ters on the profile of velocity. The stream functions have also been sketched in order to discuss the trapping behavior of the circular bolus.

关键词： Peristaltic flow Eyring-Powell fluid compliant walls rectangular duct analy-tical solution.