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An integrated land change modeler and distributed hydrological model approach for quantifying future urban runoff dynamics

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Science China Earth Sciences 2024年第10期67卷 3288-3301页

作者： Asad Hussain muhammad Waseem muhammad Ajmal muhammad Atiq Ur Rehman Tariq muhammad Jiaqing XIAO Tao YANG Pengfei SHI Institute for Disaster Risk Management School of Geographical ScienceNanjing University of Information Science and TechnologyNanjing 210044China The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China Yangtze Institute for Conservation and Development Hohai UniversityNanjing 210098China College of Hydrology and Water Resources Hohai UniversityNanjing 210098China Centre of Excellence in Water Resources Engineering University of Engineering and TechnologyLahore 54890Pakistan Department of Agricultural Engineering Faculty of CivilAgricultural and Mining EngineeringUniversity of Engineering and TechnologyPeshawar 25120Pakistan

Climate and land use changes have a significant impact on the runoff generation process in urban environments, and these effects could get worse in the future. The combined contributions of these changes have increased the risk of ***, there is a need for integrated modeling to better understand the runoff variability, especially in small urban catchments. To quantify and separate the effects of land-use changes and climate change on the hydrological response of urban catchments with a distributed hydrological model(Storm Water Management Model, SWMM), this study introduces a new integrated approach based on the Machine Learning based land use change modeler and climate change scenarios under *** on supervised classification and land use change model analysis, accumulated impervious area increase from 22%(in2023) to 33%(in 2060) was observed in the study area. Furthermore, integrating this projected increase in imperviousness with future climate change into SWMM by considering three different scenarios i.e., S1(Climate Change), S2(Combined Land Use and Climate Change), and S3(Land use Change) resulted that climate change could cause an increase in runoff from 13.2% to18.3% in peak runoff and the contribution of land use could range from 9.1% to 18.6%. Similarly, in response to the coupled effects of climate and land-use change, the runoff would likely change from 24.53% to 39.66%. Conclusively, the study showed that despite climate change, intensive urban development by the substitution of impervious surfaces could also have a severe impact on the microclimate and hydrology of small catchments. Lastly, this study could provide a way forward for the future planning and management of water resources in small catchments which could be extended to larger catchments.

关键词： Climate change Land-use modeling Runoff simulation Percent Imperviousness TerrSet

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Dynamic flexural strength of Aluminosilicate glass with a perspective of impulsive and quasi-impulsive responses: An experimental-numerical coupled evaluation

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CHINESE JOURNAL OF AERONAUTICS 2024年第12期37卷 388-403页

作者： Raza, muhammad Aamir Suo, Tao Dar, Uzair Ahmed Atif, muhammad Sheikh, muhammad Zakir Northwestern Polytech Univ Inst Extreme Mech Sch Aeronaut Xian 710072 Peoples R China Northwestern Polytech Univ Joint Int Res Ctr Impact Dynam & Its Engn Applicat Xian 710072 Peoples R China Northwestern Polytech Univ Shaanxi Key Lab Impact Dynam & Engn Applicat Xian 710072 Peoples R China Northwestern Polytech Univ Natl Key Lab Strength & Struct Integr Xian 710072 Peoples R China

The flexural strength of glass is a critical design parameter for applications encountering impact loadings. However, the micro defects, specimen geometry, loading rate, and load transformation from a quasi-dynamic to quasi-impulsive state may influence the measurement accuracy. Due to the stochastic and amorphous nature of the material, an accurate determination of the flexural strength remains a challenge. In this two-fold study, a coupled experimental-numerical strategy was devised to evaluate the dynamic flexural strength. In the first phase, three-point bending experiments were conducted on a novel "Electromagnetic Split Hopkinson Pressure Bar (ESHPB)". The incident stress signal and fracture time were recorded from experimental data, while the flexural strength was indirectly computed from a numerical algorithm. A quantitative comparison of the flexural strength with those in existing literature established the accuracy of the proposed methodology. Results of the study indicate that the specimen response became independent of the support conditions under impulsive loading. That being said, the specimen behaved like it had an infinite span length, and the measured flexural strength remained the same whether the specimen was supported or not. Besides, the specimen also maintained contact at the interfaces of the incident bar and fixture supports for the entire loading duration. In the second part of this study, the computed flexural strength was used to calibrate the existing JH-2 model. Numerical prediction of the damage propagation corroborated with that obtained from reprography images, though qualitatively. This work presents a precise and robust methodology to determine the dynamic flexural strength of brit- tle ceramics like Aluminosilicate glass over traditional experimental procedures to facilitate its adoption. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article un

关键词： Dynamic flexural strength Damage mechanism Flexural fracture Numerical simulation Aluminosilicate glass

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Structural,electronic,and magnetic behaviors of 5d transition metal atom substituted divacancy graphene：A first-principles study

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Chinese Physics B 2017年第5期26卷 304-312页

作者： Rafique muhammad 帅永 He-Ping Tan Hassan muhammad School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China Mehran University of Engineering and Technology S.Z.A.B Campus Khairpur Mir' s Sindh Pakistan

Structural, electronic, and magnetic behaviors of 5d transition metal（TM） atom substituted divacancy（DV） graphene are investigated using first-principles calculations. Different 5d TM atoms（Hf, Ta, W, Re, Os, Ir, and Pt） are embedded in graphene, these impurity atoms replace 2 carbon atoms in the graphene sheet. It is revealed that the charge transfer occurs from 5d TM atoms to the graphene layer. Hf, Ta, and W substituted graphene structures exhibit a finite band gap at high symmetric K-point in their spin up and spin down channels with 0.783 μB, 1.65 μB, and 1.78 μB magnetic moments,respectively. Ir and Pt substituted graphene structures display indirect band gap semiconductor behavior. Interestingly, Os substituted graphene shows direct band gap semiconductor behavior having a band gap of approximately 0.4 e V in their spin up channel with 1.5 μB magnetic moment. Through density of states（DOS） analysis, we can predict that d orbitals of 5d TM atoms could be responsible for introducing ferromagnetism in the graphene layer. We believe that our obtained results provide a new route for potential applications of dilute magnetic semiconductors and half-metals in spintronic devices by employing 5d transition metal atom-doped graphene complexes.

关键词： substituted impurity symmetric dilute complexes monolayer Fermi replace polarized doping

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Optimization Based on Convergence Velocity and Reliability for Hydraulic Servo System

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Chinese Journal of Aeronautics 2009年第4期22卷 407-412页

作者： muhammad Babar Nazir School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics

This article presents an optimal hybrid fuzzy proportion integral derivative （HFPID） controller based on combination of proportion integral derivative （PID） and fuzzy controllers, by which the parameters could be evaluated by global optimization either in convergence velocity or in convergence reliability. Focusing on the nonlinear factors of hydraulic servo system, this article takes advantage of PID and fuzzy logic controller integrated with scaling factors to acquire precise tracking performances. To further improve the performances, it provides new developed optimization with rapid convergence to attain reliable approach probability. Focusing on the performance indictors of evolutionary algorithm, this article presents a new technique to predict reliability of the optimization algorithm. Statistics authenticates the effectiveness and robustness of the optimization. Further, many simulation and experimental results indicate that the optimal HFPID could acquire perfect immunity against parametric uncertainties with external disturbance.

关键词： adaptive control system novel evolutionary algorithm hydraulic control equipment convergence velocity convergencereliability optimization

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Order selection in fractional Fourier transform based beamforming

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Journal of Systems Engineering and Electronics 2010年第3期21卷 361-369页

作者： muhammad Ishtiaq Ahmad School of Information and Electronics Beijing Institute of Technology

Traditionally,beamforming using fractional Fourier transform（FrFT） involves a trial-and-error based FrFT order selection which is impractical.A new numerical order selection scheme is presented based on fractional power spectra（FrFT moment） of the linear chirp *** method can adaptively determine the optimum FrFT order by maximizing the second-order central FrFT *** makes the desired chirp signal substantially concentrated whereas the noise is rejected *** improves the mean square error minimization beamformer by reducing effectively the signal-noise cross terms due to the finite data length de-correlation *** results show that the new method works well under a wide range of signal to noise ratio and signal to interference ratio.

关键词： adaptive beamforming fractional Fourier transform (FrFT) fractional moments chirp signal.

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Efect of Thermal Annealing on the Physical Properties of Zn_(1-x)Cu_xSe Thin Films Deposited by Close Spaced Sublimation Technique

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 699-706页

作者： muhammad Arslan Riaz muhammad Arshad Mahmood Rashad Rasheed Department of Applied Physics Federal Urdu University of ArtsSciences and Technology National Institute of Lasers and Optronics

Thin films of Zn1-xCuxSe （x= 0.00, 0.05, 0.10, 0.15, 0.20） were grown on glass substrates by closed space sublimation technique. The deposited films were annealed at 200 ~C and 400 ~C in air for 1 h. The annealed samples have been investigated through Rutherford backscattering spectroscopy （RBS）, X-ray diffraction （XRD）, spectroscopic ellipsometer, spectrophotometer and Raman spectroscopy. Through RBS, the composition of the films was calculated and compared with the initial concentration. Structural characteriza- tion including crystal structure, crystal orientation, lattice parameter, grain size, strain and dislocation density were carried out using XRD data. From XRD spectra it was revealed that the as-deposited and annealed films were polycrystalline in nature with zinc-blende structure. However, the crystallinity and the grain size were improved with the increase of annealing temperature. According to Raman spectroscopy, it was observed that as deposited and annealed samples have the same characteristic vibrational modes of ZnSe at low and high frequency optical phonon modes while another mode was observed for 400 ℃ annealed samples at 745 cm-1. Spectroscopic ellipsometer has been used to found annealing effect on the optical properties of ZnSe. The band gap energy has been determined using transmission spectra. It was found that the band gap energy of the film increased with the increase of annealing temperature.

关键词： Closed space sublimation Annealing effect Structural Transmission Band gap Spectroscopic ellipsometer Raman spectroscopy

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Aspect Extraction Approach for Sentiment Analysis Using Keywords

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Computers, Materials & Continua 2023年第3期74卷 6879-6892页

作者： Nafees Ayub muhammad Ramzan Talib muhammad Kashif Hanif muhammad Awais Department of Computer Science Government College UniversityFaisalabad38000Pakistan Department of Software Engineering Government College UniversityFaisalabad38000Pakistan

Sentiment Analysis deals with consumer reviews available on blogs,discussion forums,E-commerce websites,andApp *** online reviews about products are also becoming essential for consumers and companies as *** rely on these reviews to make their decisions about products and companies are also very interested in these reviews to judge their products and *** reviews are also a very precious source of information for requirement *** companies and consumers are not very satisfied with the overall sentiment;they like fine-grained knowledge about consumer *** to this,many researchers have developed approaches for aspect-based sentiment *** existing approaches concentrate on explicit aspects to analyze the sentiment,and only a few studies rely on capturing implicit *** paper proposes a Keywords-Based Aspect Extraction method,which captures both explicit and implicit *** also captures opinion words and classifies the sentiment about each *** applied semantic similarity-basedWordNet and SentiWordNet lexicon to improve aspect *** used different collections of customer reviews for experiment purposes,consisting of eight datasets over seven *** compared our approach with other state-of-the-art approaches,including Rule Selection using Greedy Algorithm(RSG),Conditional Random Fields(CRF),Rule-based Extraction(RubE),and Double Propagation(DP).Our results have shown better performance than all of these approaches.

关键词： Sentiment analysis aspect extraction keywords-based machine learning

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Surface modification techniques of membranes to improve their antifouling characteristics:recent advancements and developments

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 1837-1865页

作者： muhammad Tawalbeh Haya Aljaghoub muhammad Qasim Amani Al-Othman Sustainable and Renewable Energy Engineering Department University of SharjahSharjah 27272United Arab Emirates Sustainable Energy&Power Systems Research Centre RISEUniversity of SharjahSharjah 27272United Arab Emirates Industrial Engineering and Engineering Management Department University of SharjahSharjah 27272United Arab Emirates Department of Chemical and Biological Engineering American University of SharjahSharjah 26666United Arab Emirates Materials Science and Engineering Program College of Arts and SciencesAmerican University of SharjahSharjah 26666United Arab Emirates

Extensive research efforts are currently devoted to developing and improving conventional technologies for water treatment. Membrane-based water treatment technologies are among the most preferred options due to their commercial success, simple operation, low energy and space requirements, and high separation efficiency. Despite the advances made in membrane-based technologies, fouling remains a critical challenge. Fouling occurs upon the accumulation of unwanted impurities on the membrane surface and within the membrane pores which results in a significant decline in the membrane permeate flux. To alleviate the operational challenges from fouling, surface modification to develop antifouling membranes appears to be an effective technique. A comprehensive review of the surface modification techniques for the development of antifouling membranes is provided in this paper. Chemical surface modification techniques (grafting and plasma treatment), physical modification techniques (blending, coating, adsorption, and thermal treatment), and combined physical and chemical modification techniques have been discussed. Moreover, the challenges related to surface modification and the future research directions are addressed.

关键词： fouling antifouling membrane surface modification membrane pretreatment

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Transmit Power Optimization for Relay-Aided Multi-Carrier D2D Communication

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Tsinghua Science and Technology 2018年第1期23卷 65-74页

作者： muhammad Waqas Guftaar Ahmad Sardar Sidhu Tayyaba Jabeen muhammad Afaq Ahmad muhammad Awais Javed Department of Electrical Engineering COMSATS Institute of Information Technology (CIIT) Islamabad 44000 Pakistan Transmission Department Pakistan Telecommunication Company Limited (PTCL) Islamabad 44000 Pakistan

In this paper, we consider the power optimization problem in Orthogonal Frequency Division Multiplexing （OFDM）-based relay-enhanced device-to-device （D2D） communication. In a single cell transmission scenario, dual- hop communication is assumed in which each D2D user re-uses the spectrum of just one Cellular User （CU）. In this work, we formulate a joint optimization scheme under a Decode-and-Forward （DF） relaying protocol to maximize the sum throughput of D2D and cellular networks via power allocation over different sub-carriers. The problem is thus transformed into a standard convex optimization, subject to individual power constraints at different transmitting nodes. We exploit the duality theory to decompose the problem into several sub-problems and use Karush-Kuhn- Tucker （KKT） conditions to solve each sub-problem. We provide simulation results to validate the performance of our proposed scheme.

关键词： device-to-device communication Orthogonal Frequency Division Multiplexing (OFDM) Decode-and-Forward (DF) relay transmission power optimization

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Interdependence of friction, wear, and noise: A review

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Friction 2021年第6期9卷 1319-1345页

作者： Kevin LONTIN muhammad KHAN Cranfield University MK430ALUK

Phenomena of friction,wear,and noise in mechanical contacts are particularly important in the field of tribomechanics but equally complex if one wants to represent their exact relationship with mathematical *** have been made to describe these phenomena with different approaches in *** efforts have been compiled in different reviews but most of them treated friction,wear mechanics,and acoustic noise ***,an in-depth review that provides a critical analysis on their interdependencies is still *** this review paper,the interdependencies of friction,wear,and noise are analysed in the mechanical contacts at asperitical *** origin of frictional noise,its dependencies on contact’s mechanical properties,and its performance under different wear conditions are critically reviewed.A discussion on the existing mathematical models of friction and wear is also provided in the last section that leads to uncover the gap in the existing *** review concludes that still a comprehensive analytical modelling approach is required to relate the interdependencies of friction,noise,and wear with mathematical expressions.

关键词： noise acoustic emission wear friction

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