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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 75-80页

作者： ansar mehmood Ghulam Murtaza Tariq Mahmood Bhatti Rehana Kausar Department of Botany University of Azad Jammu and Kashmir (UAJK)Muzaffarabad-13100Pakistan Department of Chemical and Material Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)Islamabad-45650Pakistan

In the present study, an enviro-friendly synthesis of silver nanoparticles from Berberis lycium Royle leaf extract and their antibacterial efficacy against five pathogenic bacteria were investigated. This biosynthesis technique is proved to be advantageous over physical and chemical methods as no toxic chemicals are used. The structural and morphological characterization was made by UV-visible spectroscopy, scanning electron microscopy, and transmission electron microscopy. The synthesized nanoparticles were oval, rectangular, and spherical in shape, size ranges from 8 to 100 nm and exhibited an absorption peak at 458 nm. The biosynthesized silver nanoparticles have shown good antibacterial effect toward tested bacteria. It is believed that these biosynthesized silver nanoparticles can play a vital role in nano-based products in future.

关键词： Antibacterial Berberis lycium Enviro-friendly Silver nanoparticles

Numerical evaluation of enhanced green infrastructures for mitigating urban heat in a desert urban setting

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Building Simulation 2023年第9期16卷 1691-1712页

作者： Afifa Mohammed ansar Khan Mattheos Santamouris Faculty of Built Environment University of New South WalesSydneyAustralia Department of Geography Lalbaba CollegeUniversity of CalcuttaKolkataIndia

The cities of desert climates are anticipated to recognize a synergy of urban heat island(UHI)and severe heat waves during *** improve the urban thermal environment,the present study aims quantitatively explore a strategically designed network of vegetation patches called green infrastructure(GI)in subtropical desert cities such as *** achieve a more comfortable temperature environment,we built and simulated four GI situations with higher GI fractions,GI25,GI50,GI75,and *** a mesoscale urban model,the mosaic approach is utilized to test potential thermal improvement and urban climate impact,and a portion of each urban grid cell in the model domain is altered with various species of urban vegetation patches by 25%,50%,75%,and 100%.The daily peak reduction in ambient temperature at 17:00LT is similar to 0.0168℃ per unit of GI increase when compared to the untreated scenario;however,the maximum anticipated daytime summer temperature decline for GI25,GI50,GI75,and GI100 is 0.6℃,1.1℃,1.4℃,and 1.7℃,*** associated reduction in nighttime ambient temperature per unit increase in the GI is 0.0432℃,with a maximum temperature drop of around 2.4℃ for the GI100 *** GI reduces the height of the planetary boundary layer(PBL)by up to 468 m,which might lead to greater pollution *** GI-based cooling has a significant influence on delayed sea breeze and humidity,it may raise the risk of heat discomfort in the indoor building *** study adds to our understanding of the potential for GI mitigation as well as the seasonal impact of developing GIs on the desert urban boundary layer.

关键词： green infrastructure heat mitigation urban heat WRF-SLUCM Dubai city

Numerical Investigation of Micropolar Casson Fluid over a Stretching Sheet with Internal Heating

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Communications in Theoretical Physics 2017年第4期67卷 443-448页

作者： Zaffar mehmood R.mehmood Z.Iqbal Department of Mathematics HITEC UniversityTaxilaPakistan

This theoretical study investigates the microrotation effects on mixed convection flow induced by a stretching sheet. Casson fluid model along with microrotation is considered to model the governing flow problem. The system is assumed to undergo internal heating phenomenon. The governing physical problem is transformed into system of nonlinear ordinary differential equations using scaling group of transformations. These equations are solved numerically using Runge Kutta Fehlberg scheme coupled with shooting technique. Influence of sundry parameters for the case of strong and weak concentration of microelements on velocity, temperature, skin friction and local heat flux at the surface are computed and discussed. Lower skin friction and heat flux is observed for the case of weak concentration(n = 0.5)compared to strong concentration of microelements(n = 0.0) near the wall.

关键词： micropolar Casson fluid mixed convection internal heating numerical solution

An Optimization Approach of IoD Deployment for Optimal Coverage Based on Radio Frequency Model

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2627-2647页

作者： Tarek Sheltami Gamil Ahmed ansar Yasar Computer Engineering Department Interdisciplinary Research Center of Smart Mobility and LogisticsKing Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Transportation Research Institute(IMOB) Hasselt UniversityHasselt3500Belgium

Recently,Internet of Drones(IoD)has garnered significant attention due to its widespread ***,deploying IoD for area coverage poses numerous limitations and *** include interference between neighboring drones,the need for directional antennas,and altitude restrictions for *** challenges necessitate the development of efficient *** research paper presents a cooperative decision-making approach for an efficient IoDdeployment to address these challenges *** primary objective of this study is to achieve an efficient IoDdeployment strategy thatmaximizes the coverage regionwhile minimizing interference between neighboring *** deployment problem,the interference increases as the number of deployed drones increases,resulting in bad quality of *** the other hand,deploying a few drones cannot satisfy the coverage *** accomplish this,an enhanced version of a concise population-based meta-heuristic algorithm,namely Improved Particle SwarmOptimization(IPSO),is *** objective function of IPSO is defined based on the coverage probability,which is primarily influenced by the characteristics of the antennas and drone altitude.A radio frequency(RF)model is derived to evaluate the coverage quality,considering both Line of Sight(LOS)and Non-Line of Sight(NLOS)down-link coverage probabilities for ground *** is assumed that each drone is equipped with a directional antenna to optimize coverage in a given *** simulations are conducted to assess the effectiveness of the proposed *** demonstrate that the proposed method achieves maximum coverage with minimum transmission ***,a comparison is made against Collaborative Visual Area Coverage Approach(CVACA),and a game-based approach in terms of coverage quality and convergence *** simulation results reveal that our approach outperforms both CVACA and the gamebased schemes in terms of coverage an

关键词： IoD line of sight optimal deployment IPSO RF model

ASLP-DL—A Novel Approach Employing Lightweight Deep Learning Framework for Optimizing Accident Severity Level Prediction

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Computers, Materials & Continua 2024年第2期78卷 2535-2555页

作者： Saba Awan Zahid mehmood Department of Software Engineering University of Engineering and TechnologyTaxila47050Pakistan Department of Computer Engineering University of Engineering and TechnologyTaxila47050Pakistan

Highway safety researchers focus on crash injury severity,utilizing deep learning—specifically,deep neural networks(DNN),deep convolutional neural networks(D-CNN),and deep recurrent neural networks(D-RNN)—as the preferred method for modeling accident *** learning’s strength lies in handling intricate relation-ships within extensive datasets,making it popular for accident severity level(ASL)prediction and *** prior success,there is a need for an efficient system recognizing ASL in diverse road *** address this,we present an innovative Accident Severity Level Prediction Deep Learning(ASLP-DL)framework,incorporating DNN,D-CNN,and D-RNN models fine-tuned through iterative hyperparameter selection with Stochastic Gradient *** framework optimizes hidden layers and integrates data augmentation,Gaussian noise,and dropout regularization for improved *** and factor contribution analyses identify influential *** on three diverse crash record databases—NCDB 2018–2019,UK 2015–2020,and US 2016–2021—the D-RNN model excels with an ACC score of 89.0281%,a Roc Area of 0.751,an F-estimate of 0.941,and a Kappa score of 0.0629 over the NCDB *** proposed framework consistently outperforms traditional methods,existing machine learning,and deep learning techniques.

关键词： Injury severity prediction deep learning feature

Polarization multiplexing based duplex radio-over-fiber link for millimeter wave signal transmission to a ring of multiple radio access units

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 300-306页

作者： Tayyab mehmood Hina QAYYUM Salman GHAFOOR School of Electrical Engineering and Computer Science National University of Sciences and Technology

A radio-over-fiber(RoF) distributed antenna system(DAS) architecture is proposed, where millimeter wave(mm-wave) signals are transmitted to four different radio access units(RAUs) arranged in a ring *** proposed architecture transmits duplex data of 128 Mb/s to each RAU in both downlink(DL) and uplink(UL)directions. The radio frequency(RF) signals are transmitted by polarization multiplexing a multi-wavelength ***-wave signals at a frequency of 25 GHz are generated at each RAU using remote heterodyne *** proposed architecture provides increased coverage while maintaining good bit error rate(BER) results.

关键词： Radio over fiber Millimeter wave Radio access units

Sensitivity-based upscaling for history matching of reservoir models

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Petroleum Science 2016年第3期13卷 517-531页

作者： Saad mehmood Abeeb A.Awotunde United Energy Pakistan Bahria Complex-l M.T. Khan Road Karachi 74000 Sindh Pakistan Department of Petroleum Engineering King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

Simulation of reservoir flow processes at the finest scale is computationally expensive and in some cases ***,upscaling of several fine-scale grid blocks into fewer coarse-scale grids has become an integral part of reservoir simulation for most *** is because as the number of grid blocks increases,the number of flow equations increases and this increases,in large proportion,the time required for solving flow *** we can adopt parallel computation to share the load,a large number of grid blocks still pose significant computational ***,upscaling acts as a bridge between the reservoir scale and the simulation *** as the upscaling ratio is increased,the accuracy of the numerical simulation is reduced;hence,there is a need to keep a balance between the *** this work,we present a sensitivity-based upscaling technique that is applicable during history *** method involves partial homogenization of the reservoir model based on the model reduction pattern obtained from analysis of the sensitivity *** technique is based on wavelet transformation and reduction of the data and model spaces as presented in the 2Dwp-wk *** the 2Dwp-wk approach,a set of wavelets of measured data is first selected and then a reduced model space composed of important wavelets is gradually built during the first few iterations of nonlinear *** building of the reduced model space is done by thresholding the full wavelet sensitivity *** pattern of permeability distribution in the reservoir resulting from the thresholding of the full wavelet sensitivity matrix is used to determine the neighboring grids that are *** essence,neighboring grid blocks having the same permeability values due to model space reduction are combined into a single grid block in the simulation model,thus integrating upscaling with wavelet multiscale inverse *** apply the method to estimate the parameters

关键词： Upscaling Inverse analysis History matching Sensitivity Wavelets

Energy-Efficient UAVs Coverage Path Planning Approach

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 3239-3263页

作者： Gamil Ahmed Tarek Sheltami Ashraf Mahmoud ansar Yasar Computer Engineering Department Interdisciplinary Research Center of Smart Mobility and LogisticsKing Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Transportation Research Institute(IMOB) Hasselt UniversityHasselt3500Belgium

Unmanned aerial vehicles(UAVs),commonly known as drones,have drawn significant consideration thanks to their agility,mobility,and flexibility *** play a crucial role in modern reconnaissance,inspection,intelligence,and surveillance *** path planning(CPP)which is one of the crucial aspects that determines an intelligent system’s quality seeks an optimal trajectory to fully cover the region of interest(ROI).However,the flight time of the UAV is limited due to a battery limitation and may not cover the whole region,especially in large ***,energy consumption is one of the most challenging issues that need to be *** this paper,we propose an energy-efficient coverage path planning algorithm to solve the CPP *** objective is to generate a collision-free coverage path that minimizes the overall energy consumption and guarantees covering the whole *** do so,the flight path is optimized and the number of turns is reduced to minimize the energy *** proposed approach first decomposes the ROI into a set of cells depending on a UAV camera ***,the coverage path planning problem is formulated,where the exact solution is determined using the CPLEX *** small-scale problems,the CPLEX shows a better solution in a reasonable ***,the CPLEX solver fails to generate the solution within a reasonable time for large-scale ***,to solve the model for large-scale problems,simulated annealing forCPP is *** results show that heuristic approaches yield a better solution for large-scale problems within amuch shorter execution time than the CPLEX ***,we compare the simulated annealing against the greedy *** results show that simulated annealing outperforms the greedy algorithm in generating better solution quality.

关键词： Coverage path planning MILP CPLEX solver energy model optimization region of interest area of interest

A review and taxonomy of wind and solar energy forecasting methods based on deep learning

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Energy and AI 2021年第2期4卷 136-160页

作者： Ghadah Alkhayat Rashid mehmood Department of Computer Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah 21589Saudi Arabia High Performance Computing Centre King Abdulaziz UniversityJeddah 21589Saudi Arabia

Renewable energy is essential for planet *** energy output forecasting has a significant impact on making decisions related to operating and managing power *** prediction of renewable energy output is vital to ensure grid reliability and permanency and reduce the risk and cost of the energy market and *** learning’s recent success in many applications has attracted researchers to this field and its promising potential is manifested in the richness of the proposed methods and the increasing number of *** facilitate further research and development in this area,this paper provides a review of deep learning-based solar and wind energy forecasting research published during the last five years discussing extensively the data and datasets used in the reviewed works,the data pre-processing methods,deterministic and probabilistic methods,and evaluation and comparison *** core characteristics of all the reviewed works are summarised in tabular forms to enable methodological *** current challenges in the field and future research directions are *** trends show that hybrid forecasting models are the most used in this field followed by Recurrent Neural Network models including Long Short-Term Memory and Gated Recurrent Unit,and in the third place Convolutional Neural *** also find that probabilistic and multistep ahead forecasting methods are gaining more ***,we devise a broad taxonomy of the research using the key insights gained from this extensive review,the taxonomy we believe will be vital in understanding the cutting-edge and accelerating innovation in this field.

关键词： Deep learning Renewable energy forecasting Solar energy Wind energy Taxonomy Hybrid methods

A New Approach to Vague Soft Bi-Topological Spaces

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Computer Modeling in Engineering & Sciences 2022年第4期131卷 411-428页

作者： Arif mehmood Saleem Abdullah Choonkil Park Department of Mathematics&Statistics Riphah International UniversityIslamabad44000Pakistan Department of Mathematics AbdulWali Khan UniversityMardan23200Pakistan Department of Mathematics Research Institute for Natural SciencesHanyang UniversitySeoul04763Korea

Fuzzy soft topology considers only membership *** has nothing to do with the non-membership *** an extension was needed in this *** soft topology addresses bothmembership and non-membership values *** vague soft topology(single structure)is unable to address some complex *** an extension to vague soft bi-topology(double structure)was needed in this *** make this situation more meaningful,a new concept of vague soft bi-topological space is introduced and its structural characteristics are attempted with a new *** this article,new concept of vague soft bi-topological space(VSBTS)is initiated and its structural behaviors are *** approach is based on generalized vague soft open sets,known as vague softβopen *** ample of examples are given to understand the *** the non-validity of some results,counter examples are provided to pay the ***-wise vague softβopen and pair-wise vague softβclose sets are alsoaddressedwith examples in(VSBTS).Vague soft separation axioms are initiatedin(VSBTS)concerning soft points of the *** separation axioms are also addressed relative to soft points of the *** soft bi-topological properties are studied with the application of vague softβopen sets with respect to soft points of the *** characterization of vague softβclose as well as vague softβopen sets,characteristics of Bolzano Weirstrass property,vague soft compactness and its marriage with sequences,interconnection between sequential compactness and countable compactness in(VSBTS)with respect to softβopen sets are addressed.

关键词： Vague soft set vague soft point vague soft bi-topological space vague softβ-open set and vague softβ-separation axioms