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Chinese Physics Letters 2008年第1期25卷 137-140页

作者： munazza zulfiqar ali tariq abdullah Centre of Excellence in Solid State Physics Quaid-i-Azam Campus Punjab University Lahore 54590 Pakistan

We investigate the effects of introducing a defect layer negative material layers on the transmission properties in a one-dimensional photonic crystal containing single The width of the defect layer is taken to be the same or smaller than the period of the structure. Different cases of the defect layer being linear or nonlinear and double positive or double negative are discussed. It is found that only a nonlinear double negative layer gives rises to a localized mode within the zero-Φeff gap in this kind of structure. It is also shown that the important characteristics of the nonlinear defect mode such as its frequency, its FWHM and the threshold of the associated bistability can be controlled by changing the widths of the defect layer and the host layers.

关键词： pulsars x-ray spectra relativity and gravitation redshift

Properties of single and multiple defect modes in one-dimensional photonic crystals containing left-handed metamaterials

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Chinese Optics Letters 2012年第7期10卷 69-72页

作者： munazza zulfiqar ali Physics Department Punjab University

Wave propagation is studied in structures consisting of alternate left- and right-handed layers. Bragg gap and zero-n gap appear in different frequency regions of the structure. The periodicity of the structure is broken by simply reversing the order of the layers in one half of the structure, resulting in defect modes located inside the zero-n gap and Bragg gap. These modes can be made very narrow by adding more layers in the structure. The defect mode located inside the zero-n gap is sensitive to the symmetry of the structure and insensitive to the angle of incidence of the incoming radiation. Multiple modes are also generated inside the gaps by repeating the structural pattern. Thus, a simple structure can be used for single and multiple modes that are imDortant for different applications.

关键词： mode Properties of single and multiple defect modes in one-dimensional photonic crystals containing left-handed metamaterials left

Selection of Metaheuristic Algorithm to Design Wireless Sensor Network

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Intelligent Automation & Soft Computing 2023年第7期37卷 985-1000页

作者： Rakhshan zulfiqar tariq Javed Zain Anwar ali Eman H.Alkhammash Myriam Hadjouni Hamdard University Karachi75270Pakistan Electronic Engineering Department Sir Syed University of Engineering&TechnologyKarachiPakistan Department of Computer Science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Computer Sciences College of Computer and Information SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

The deployment of sensor nodes is an important aspect in mobile wireless sensor networks for increasing network *** longevity of the networks is mostly determined by the proportion of energy consumed and the sensor nodes’access *** optimal or ideal positioning of sensors improves the portable sensor networks *** and energy usage are mostly determined by successful sensor placement ***-inspired algorithms are the most effective solution for short sensor *** primary objective of work is to conduct a comparative analysis of nature-inspired optimization for wireless sensor networks(WSNs’)maximum network ***,it identifies quantity of installed sensor nodes for the given *** of algorithm has been identified based on value of optimized *** first half of the paper’s literature on nature-inspired algorithms is *** six metaheuristics algorithms(Grey wolf,Ant lion,Dragonfly,Whale,Moth flame,Sine cosine optimizer)are compared for optimal coverage of *** simulation outcomes confirm that whale opti-mization algorithm(WOA)gives optimized Energy with improved network coverage with the least number of *** comparison will be helpful for researchers who will use WSNs in their applications.

关键词： Bio-inspired computing evolutionary computation greedy algorithms wireless sensor network computational intelligence

Global transmission diagrams for evanescent waves in a nonlinear hyperbolic metamaterial

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Chinese Optics Letters 2015年第9期13卷 1-5页

作者： munazza zulfiqar ali Ashfaq Ahmad Bhatti Qamar ul Haque Shahzad Mahmood Physics Department Punjab University Theoretical Physics Division PINSTECH

A theoretical model of a nonlinear hyperbolic metamaterial is presented in the form of a stack of subwavelength layers of linear plasmonic and nonlinear dielectric materials. A broad picture of the properties of evanescent waves （high-k modes） in this stack is investigated by plotting global transmission diagrams. The presence of nonlinearity strongly modifies these diagrams. The emergence and modification of nonlinear evanescent waves is observed. Some signatures of nonlinear phenomenon such as formation of orbits and trajectories around fixed points are also seen in our work.

关键词： Global transmission diagrams for evanescent waves in a nonlinear hyperbolic metamaterial

Clean production of lactic acid by selective carbon-carbon bond cleavage of biomass feedstock over a novel carbon-bismuth oxychloride photocatalyst

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 69-81页

作者： zulfiqar ali Jiliang Ma Dongnv Jin Rui Cui Runcang Sun Liaoning Key Lab of Lignocellulose Chemistry and Biomaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China

The use of functional materials such as carbon-bismuth oxyhalides in integrated photorefineries for the clean production of fine chemicals requires restructuring.A facile biomass-assisted solvothermal fabrication of carbon/bismuth oxychloride nanocomposites(C/BiOCl)was achieved at various *** with BiOCl and C/BiOCl-120,C/BiOCl-180 exhibited higher crystallinity,wider visible light absorption,and a faster migration/separation rate of photoinduced *** the selective C–C bond cleavage of biomass-based feedstocks photocatalyzed by C/BiOCl-180,the xylose conversion and lactic acid yield were 100%and 92.5%,respectively.C/BiOCl-180 efficiently converted different biomass-based monosaccharides to lactic acid,and the efficiency of pentoses was higher than that of ***,lactic acid synthesis was favored by all active radicals including superoxide ion(·O_(2)^(−)),holes(h^(+)),hydroxyl radical(·OH),and singlet oxygen(^(1)O_(2)),with·O_(2)^(−)playing a key *** fabricated photocatalyst was stable,economical,and *** use of biomass-derived monosaccharides for the clean production of lactic acid via the C/BiOCl-180 photocatalyst has opened new research horizons for the investigation and application of C–C bond cleavage in biomass-based feedstocks.

关键词： carbon-carbon bond cleavage biomass reforming C/BiOCl lactic acid photocatalysis

Effect of loading rate and time delay on the tangent modulus method(TMM)in coal and coal measured rocks

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International Journal of Coal Science & Technology 2022年第6期9卷 51-63页

作者： zulfiqar ali Murat Karakus Giang D.Nguyen Khalid Amrouch School of Civil Environmental and Mining EngineeringUniversity of AdelaideAdelaideSA 5000Australia Australian School of Petroleum and Energy University of AdelaideAdelaideSA 5000Australia Geology&Sustainable Mining Mohammed VI Polytechnic University43150 BenguerirMorocco

Non-destructive techniques of in-situ stress measurement from oriented cored rocks have great potential to be developed as a cost cost-effective and reliable alternative to the conventional overcoring and hydraulic fracturing *** tangent modulus method(TMM)is one such technique that can be applied to oriented cored rocks to measure in-situ *** the deformation rate analysis(DRA),the rock specimen is subjected to two cycles of uniaxial compression and the stress-tangent modulus curve for the two cycles is obtained from the stress-strain curve.A bending point in the tangent modulus curve of the first cycle is observed,separating it from the tangent modulus curve of the second *** point of separation between the two curves is assumed to be the previously applied maximum stress.A number of experiments were conducted on coal and coal measured rocks(sandstone and limestone)to understand the effect of loading conditions and the time *** specimens were preloaded,and cyclic compressions were applied under three different modes of loading,four different strain rates,and time delays of up to one *** bending point in the stress-tangent modulus curves occurred approximately at the applied pre-stress levels under all three loading modes,and no effect of loading rate was observed on the bending points in ***,a clear effect of time delay was observed on the TMM,contradicting the DRA *** could be due to the sensitivity of TMM and the range of its applicability,all of which need further investigation for the in-situ stress measurement.

关键词： Tangent modulus method TMM Deformation rate analysis DRA Time delay Strain rate

Graphene Nanosheets Decorated with Copper Oxide Nanoparticles for the Photodegradation of Methylene Blue

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Chemical Research in Chinese Universities 2022年第6期38卷 1518-1525页

作者： Samavia RAFIQ zulfiqar ali RAZA Muhammad ASLAM Muhammad Junaid BAKHTIYAR Department of Applied Sciences National Textile UniversityFaisalabad37610Pakistan

Textile industries extensively use colorants,such as methylene blue,and if disposed off untreated,they contaminate the effluent streams,causing a severe impact on the environment and aquatic *** degradation has been found as an inevitable approach to treat ***,we decorated the copper oxide nanoparticles on graphene nanosheets during the reflux *** resultant copper oxide/graphene nanocomposites were analyzed for structural and functional *** was observed that on increasing the copper oxide contents,the z-average size of the resultant nanocomposites *** X-ray diffraction analysis demonstrated the crystalline nature of the *** surface morphology of the copper oxide nanoparticles appeared to be spherical and that of the copper oxide/graphene composite somehow *** infrared analysis indicated successful intercalation of precursors in the *** bandgap of copper oxide/graphene nanocomposites varied in the range of 1.03—1.30 eV,which indicated their effective photocatalytic *** results demonstrated that after 120 min of exposure,the methylene blue removal efficiency reached 94.0%,92.2%,and 89.4%(mass fraction)on the copper oxide/graphene nanocomposite at copper oxide nanoparticles to graphene nanosheets ratios of 1:1,1.5:1,and 2:1(mass ratio),*** photodegradation performance of the prepared nano-catalyst was found satisfactory even after five cycles.

关键词： Copper oxide Graphene nanosheet Methylene blue Photocatalysis

Effective medium parameters for 1D photonic crystal containing single-negative material layers using the envelope function approach

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Chinese Optics Letters 2013年第4期11卷 1-3页

作者： munazza Zulf iqar ali Physics Department Quaid-i-Azam Campus Punjab University

Nonlinear wave propagation in a 1D photonic crystal containing single-negative layers is investigated using the multiple-scale method. In this approach, the electric field is decomposed into a slowly varying envelope function and a fast Bloch-like function to obtain the analytic expressions of the effective parameters of an equivalent medium. The periodic structure has an equivalent left-handed medium for the envelope function. Gap soliton formation is discussed and compared with that associated with the Bragg gap.

关键词： 050.5298 Photonic crystals 060.4370 Nonlinear optics, fibers 070.7345 Wave propagation

Geotechnical forensic investigation of a slope failure on silty clay soil--A case study

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 501-517页

作者： Mohammad Abubakar NAVEED zulfiqar ali Abdul QADIR Umar Naveed LATIF Saad HAMID Umar SARWAR Military College of Engineering National University of Sciences and TechnologyRisalpur 24080Pakistan School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaibe 5096Australia

Qila Bala Hisar is one of the noteworthy places of Peshawar,Khyber *** fort was constructed on a flled ground during the 18th century and it was renovated several times by the occupants ever ***,due to an earthquake of magnitude 7.3,the upper part of the south-western wall of the fort *** collapse of the wall was attributed to the failure of the retained *** research was undertaken to characterize the slope material,study causal factors of failure and evaluate remedial *** investigation involved conventional field and laboratory testing and geophysical investigation using electrical resistivity technique to evaluate the nature of ***,X-ray Diffraction and Scanning Electron Microscopy was used to study the slope material at a molecular level to evaluate the existence of swelling *** analysis has shown that excessive seepage of water caused by the poor maintenance of runoff and sewage drains is the causal factor triggered by the seismic event.A remedial strategy involving soil nails,micro piles and improvement of the surface drainage is recommended.

关键词： forensic geotechnical investigation slope failure slope analysis finite element method numerical analysis seismic loading Qila Bala Hisar

Push-Based Content Dissemination and Machine Learning-Oriented Illusion Attack Detection in Vehicular Named Data Networking

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Computers, Materials & Continua 2023年第9期76卷 3131-3150页

作者： Arif Hussain Magsi Ghulam Muhammad Sajida Karim Saifullah Memon zulfiqar ali State Key Laboratory ofNetworking and Switching Technology Beijing University of Post and TelecommunicationBeijing100876China Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia School of Computer Science and Technology Harbin Institute of TechnologyHarbin150001China School of Computer Science and Electronic Engineering University of EssexColchesterCO43SQUK

Recent advancements in the Vehicular Ad-hoc Network(VANET)have tremendously addressed road-related ***,Named Data Networking(NDN)in VANET has emerged as a vital technology due to its outstanding ***,the NDN communication framework fails to address two important *** current NDN employs a pull-based content retrieval network,which is inefficient in disseminating crucial content in Vehicular Named Data Networking(VNDN).Additionally,VNDN is vulnerable to illusion attackers due to the administrative-less network of autonomous *** various solutions have been proposed for detecting vehicles’behavior,they inadequately addressed the challenges specific to *** deal with these two issues,we propose a novel push-based crucial content dissemination scheme that extends the scope of VNDN from pullbased content retrieval to a push-based content forwarding *** addition,we exploitMachine Learning(ML)techniques within VNDN to detect the behavior of vehicles and classify them as attackers or *** trained and tested our system on the publicly accessible dataset Vehicular Reference Misbehavior(VeReMi).We employed fiveML classification algorithms and constructed the bestmodel for illusion attack *** results indicate that RandomForest(RF)achieved excellent accuracy in detecting all illusion attack types in VeReMi,with an accuracy rate of 100%for type 1 and type 2,96%for type 4 and type 16,and 95%for type ***,RF can effectively evaluate the behavior of vehicles and identify attacker vehicles with high *** ultimate goal of our research is to improve content exchange and ***,ourML-based attack detection and preventionmechanismensures trustworthy content dissemination and prevents attacker vehicles from sharing misleading information in VNDN.

关键词： Named data networking vehicular networks pull-push illusion attack machine learning