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International Journal of Minerals,Metallurgy and Materials 2023年第12期30卷 2375-2385页

作者： Yiqi Zhou Sultan mahmood Dirk Lars Engelberg Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Metallurgy and Corrosion School of MaterialsThe University of ManchesterM139PLManchesterUK Materials Performance Centre The University of ManchesterM139PLManchesterUK

Bipolar electrochemistry is used to produce a linear potential gradient across a bipolar electrode(BPE),providing direct access to the anodic and cathodic reactions under a wide range of applied *** occurrence of pitting corrosion,crevice corrosion,and general corrosion on type 2205 duplex stainless steel(DSS 2205)BPE has been observed at room *** critical pit depth of 10-20μm with a55%-75% probability of pits developing into stable pits at potential from+0.9 to+1.2 V ***(open circuit potential)are *** pit nucleation sites are either within ferritic grains or at the interface between austenite and *** critical conditions for pitting and crevice corrosion are discussed with Epit(critical pitting potential)and Ecre(critical crevice potential)decreasing from 0.87 and 0.80 V *** after150 s of exposure to 0.84 and 0.76 V *** after 900 s of exposure,*** growth kinetics under different applied bipolar potentials and exposure times have been *** ferrite is shown to be more susceptible to general dissolution.

关键词： bipolar electrochemistry duplex stainless steel pitting corrosion pit growth factor crevice corrosion

Studies on batch adsorptive removal of cadmium and nickel from synthetic waste water using silty clay originated from Balochistan-Pakistan

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1171-1176页

作者： Abdul Samad Muhammad Imran Din mahmood Ahmed Institute of Chemistry University of the PunjabLahore 54590Pakistan Renacon Pharma Limited Lahore 54600Pakistan

The potentials of silty clay(SC),acquired from Chaman,Balochistan,were investigated as adsorbent for Ni(Ⅱ)and Cd(Ⅱ)removal from contaminated *** influence of different operating factors like dose,pH,temperature,and time of contact was explored,and optimum values were noted under batch adsorption *** study was conducted with varying concentrations of solutions on optimized conditions and different adsorption models i.e.,Langmuir,Freundlich,Temkin and Dubinin-Radushkevich(D-R)isotherm,which were employed to interpret the *** isothermal data of both Ni(Ⅱ)and Cd(Ⅱ)were well fitted to Langmuir isotherm suggesting the formation of monolayer of metal ions on silty *** values of adsorption capacity noted for Ni(Ⅱ)and Cd(Ⅱ)were 3.603 mg·g^-1 and 5.480 mg·g^-1,*** studies affirmed that pseudo second order(PSO)kinetics was being obeyed by the removal of Ni(Ⅱ)and Cd(Ⅱ).Thermodynamic variables like free energy change(ΔG°),enthalpy change(ΔH°)and entropy change(ΔS°)were *** negative value ofΔG°and the positive values ofΔH°andΔS°unfolded that the removal process of both metal ions of by SC was spontaneous,endothermic and feasible.

关键词： Adsorption Kinetics Isotherm Toxicity Silty clay Thermodynamics

Defocus Blur Segmentation Using Local Binary Patterns with Adaptive Threshold

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Computers, Materials & Continua 2022年第4期71卷 1597-1611页

作者： Usman Ali Muhammad Tariq mahmood Future Convergence Engineering School of Computer Science and EngineeringKorea University of Technology and Education1600Chungjeol-roByeongcheon-myeonCheonan31253Korea

Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the *** to the limited available information about blur type,scenario and the level of blurriness,detection and segmentation is a challenging ***,the performance of the blur measure operator is an essential factor and needs improvement to attain *** this paper,we propose an effective blur measure based on local binary pattern(LBP)with adaptive threshold for blur *** sharpness metric developed based on LBP used a fixed threshold irrespective of the type and level of blur,that may not be suitable for images with variations in imaging conditions,blur amount and ***,the proposed measure uses an adaptive threshold for each input image based on the image and blur properties to generate improved sharpness *** adaptive threshold is computed based on the model learned through support vector machine(SVM).The performance of the proposed method is evaluated using two different datasets and is compared with five state-of-the-art *** analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all of the compared methods.

关键词： Adaptive threshold blur measure defocus blur segmentation local binary pattern support vector machine

Adaptive Deep Learning Model to Enhance Smart Greenhouse Agriculture

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Computers, Materials & Continua 2023年第11期77卷 2545-2564页

作者： Medhat A.Tawfeek Nacim Yanes Leila Jamel Ghadah Aldehim mahmood A.mahmood Department of Computer Science College of Computer and Information SciencesJouf UniversityP.O.Box 72314SkakaSaudi Arabia Department of Computer Science Faculty of Computers and InformationMenoufia UniversityP.O.Box 6121890MenoufiaEgypt Department of Software Engineering College of Computer and Information SciencesJouf UniversityP.O.Box 72314SkakaSaudi Arabia RIADI Laboratory La Manouba UniversityP.O.Box2010ManoubaTunisia Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Information Systems and Technology Faculty of Graduate Studies and ResearchCairo UniversityP.O.Box 3753450GizaEgypt

The trend towards smart greenhouses stems from various factors,including a lack of agricultural land area owing to population concentration and housing construction on agricultural land,as well as water *** study proposes building a full farming adaptation model that depends on current sensor readings and available datasets from different agricultural research *** proposed model uses a one-dimensional convolutional neural network(CNN)deep learning model to control the growth of strategic crops,including cucumber,pepper,tomato,and *** proposed model uses the Internet of Things(IoT)to collect data on agricultural operations and then uses this data to control and monitor these operations in real *** helps to ensure that crops are getting the right amount of fertilizer,water,light,and temperature,which can lead to improved yields and a reduced risk of crop *** dataset is based on data collected from expert farmers,the photovoltaic construction process,agricultural engineers,and research *** experimental results showed that the precision,recall,F1-measures,and accuracy of the one-dimensional CNN for the tested dataset were approximately 97.3%,98.2%,97.25%,and 97.56%,*** new smart greenhouse automation system was also evaluated on four crops with a high turnover *** system has been found to be highly effective in terms of crop productivity,temperature management and water conservation.

关键词： Greenhouse wireless sensor network deep learning Internet of Things strategic crops monitoring smart irrigation

Surface Modification of Poly Vinyl Chloride (PVC) Using Low Pressure Argon and Oxygen Plasma

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Plasma Science and Technology 2010年第2期12卷 204-207页

作者： mahmood GHORANNEVISS Sheila SHAHIDI Jakub WIENER Plasma Physics Research Center Science and Research Branch Islamic Azad University Department of Textile Chemistry Faculty of Textile Technical University of Liberec

In this study, commercial poly vinyl chloride （PVC） films were treated by oxygen and argon plasmas in a cylindrical glass tube which was surrounded by a DC variable magnetic field, with different sample positions in the plasma reactor and also different exposure durations. Effects of the plasma treatment on the hydrophilic properties of the films were studied by mea- suring the water drop contact angle on the surface of the samples. The surface topography of the untreated and plasma treated films was analyzed and compared by atomic force microscopy （AFM）. The optical characteristic changes in treated samples were investigated using reflective spectrophotometry. Also, the chemical changes which appeared on the surface of the samples were investigated using Fourier transform infrared spectroscopy （FTIR）. The results show that the plasma treated PVC becomes more hydrophilic with an enhanced wettability. A sharp de- crease in the water contact angle may also be a consequence of the surface texturization. The aging effect on wettability of the samples was also investigated. The results show that the effect of oxygen plasma on the surface properties of the samples is more pronounced compared with that of argon plasma.

关键词： plasma surface modification poly vinyl chloride

Productivity comparison of radial lateral wells and horizontal snake wells applied to marine gas hydrate reservoir development

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Petroleum 2021年第4期7卷 407-413页

作者： Md Nahin mahmood Boyun Guo Department of Petroleum and Mining Engineering Chittagong University of Engineering&TechnologyChattogram4349Bangladesh Department of Petroleum Engineering University of LouisianaLafayetteLA70504USA

Development of marine gas hydrate resources presents a huge challenge to the energy industry owing to the well production complications such as wellbore collapse,sand production,and low *** lateral wells(RLW)and horizontal snake wells(HSW)have been proposed separately to mitigate these *** compare the productivity potentials of these two types of wells using the recently developed analytical models and field case data from a gas hydrate reservoir in the South China *** is concluded that RLW will yield slightly higher gas productivity than HSW under similar con*** analysis with the well models indicates that the productivity of RLW is directly proportional to the number of laterals,length of laterals,and radius of laterals,while the productivity of HSW is directly proportional to the length and radius of the horizontal *** decision of using RLW or HSW can be made based on economic analysis of well completion and production,which should be addressed in future studies.

关键词： Natural gas hydrate Radial lateral wells Horizontal snake wells Productivity

Causes of recurring drought patterns in Xinjiang, China

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Journal of Arid Land 2010年第4期2卷 279-285页

作者： Rashed mahmood Babar KHAN Nansen-Zhu International Research Center Institute of Atmospheric Physics CAS Xinjiang Institute of Ecology and Geography CAS

Xinjiang Uygur Autonomous Region of China, with its unique topography and geographical location receives very less precipitation in summer as compared with other parts of China. The region is a land locked where moisture is supplied only by westerly winds from Atlantic Ocean as the moisture coming from Indian Ocean is mostly blocked by the Himalayas Range and the Tibetan plateau. In such a scenario, Xinjiang faces severe drought conditions offering significant challenges to water management. In this paper, we analyzed the drought periods in Xinjiang and discussed the various factors that might have influenced precipitation over the past forty-four years. For this purpose, we defined three periods of consecutive four years for high and low precipitation intensities. The average observed precipitation was 1.05 mm/day and 0.7 mm/day in summer (June-July-August) for the Tianshan Mountain region and Junggar Basin of Xinjiang, respectively. The drought conditions indicated that high sea level pressure, wind divergence and low convection were the prominent features that caused the droughts, which often do not allow the condensation process to coagulate the tiny water droplets into relatively large raindrops reducing the amount of precipitation in the region. The period of 1983-1986 is the lowest precipitation interval indicating the severe drought in the western Xinjiang (i.e western Tianshan Mountain region), for which, less moisture availability, strong divergence and less convection could be the most influencing factors.

关键词： Xinjiang drought topography moisture availability convection raindrops divergence

Hybrid Dynamic Neural Network and PID Control of Pneumatic Artificial Muscle Using the PSO Algorithm

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International Journal of Automation and computing 2020年第3期17卷 428-438页

作者： Mahdi Chavoshian Mostafa Taghizadeh mahmood Mazare School of Mechanical Engineering Sh.Beheshti UniversityTehran 16589-53571Iran

Pneumatic artificial muscles(PAM)have been recently considered as a prominent challenge regarding pneumatic actuators specifically for rehabilitation and medical *** accomplishing accurate control of the PAM is comparatively complicated due to time-varying behavior,elasticity and ambiguous characteristics,a high performance and efficient control approach should be *** of the mentioned challenges,limited course length is another predicament with the PAM *** this regard,this paper proposes a new hybrid dynamic neural network(DNN)and proportional integral derivative(PID)controller for the position of the *** order to enhance the proficiency of the controller,the problem under study is designed in the form of an optimization *** the potential of particle swarm optimization,it has been applied to optimally tune the PID-DNN *** verify the performance of the proposed controller,it has been implemented on a real-time system and compared to a conventional sliding mode *** and experimental results show the effectiveness of the proposed controller in tracking the reference signals in the entire course of the PAM.

关键词： Dynamic neural network(DNN)control hybrid control pneumatic muscle particle swarm optimization sliding mode control

Phytochemical investigation of medicinally important plants of the Pothohar region of Pakistan

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Journal of Traditional Chinese Medicine 2020年第5期40卷 883-890页

作者： Amna Rabab Sobia Kanwal Tariq mahmood Department of Plant Sciences Quaid-i-Azam UniversityIslamabad 45320Pakistan Department of Zoology University of GujratSub-Campus Rawalpindi 46000Pakistan

OBJECTIVE:To report the phytochemical composition(flavonoids,phenolics,saponins,tannins,and terpenoids)and biological activities(antioxidant,phytotoxic,cytotoxic,antifungal activities)of medicinally important plants of Pothohar ***:In the current study various qualitative and quantitative phytochemical tests were conducted to investigate the phytochemical composition of plant extracts prepared in benzene,chloroform and *** same extracts were further utilized in different biological activities i.e.,antioxidant[total antioxidant capacity,total reducing power,and 2,2-diphenyl-1-picrylhydrazyl(DPPH)scavenging assay],phytotoxicity(Radish seed bioassay),brine shrimp cytotoxicity and antifungal activities(against four pathogenic fungal strains).RESULTS:Phytochemical analysis indicate flavonoids,phenolics,saponins,tannins and terpenoids were present in almost all plants however,maximum amount of total phenolic and flavonoid contents was reported in of Malva parviflora and Lepidium *** of Malva parviflora and Lepidium pinnatifidum also depicted the superlative antioxidant activity(total antioxidant capacity,total reducing power,and DPPH scavenging activity).Maximum fungal growth inhibition was demonstrated by extracts of Centaurea calcitropa,Vicia sativa and Malva *** maximum cytotoxicity was shown by the extracts of Centaurea ***,for phytotoxicity assay the highest allelopathic potential was exhibited by extracts of Lepidium *** prejudiced results;the best results were obtained by Methanol followed by Chloroform and ***:Centaurea calcitropa,Vicia sativa,Malva parviflora and Lepidium pinnatifidum are most promising medicinal plants of Pothohar region for future studies.

关键词： Centaurea Malva Cytotoxins Antifungal agents Phytotoxicity Pothohar region

Exact solutions for the flow of second grade fluid in annulus between torsionally oscillating cylinders

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Acta Mechanica Sinica 2011年第2期27卷 222-227页

作者： Amir mahmood Saima Parveen Najeeb Alam Khan Department of Mathematics COMSATS Institute of Information Technology Lahore Pakistan Abdus Salam School of Mathematical Sciences Lahore Pakistan Department of Mathematics University of Karachi Karachi-75270 Pakistan

The velocity field and the associated shear stress corresponding to the torsional oscillatory flow of a second grade fluid, between two infinite coaxial circular cylinders, are determined by means of the Laplace and Hankel transforms. At time t = 0, the fluid and both the cylinders are at rest and at t = 0 ＋ , cylinders suddenly begin to oscillate around their common axis in a simple harmonic way having angular frequencies ω 1 and ω 2 . The obtained solutions satisfy the governing differential equation and all imposed initial and boundary conditions. The solutions for the motion between the cylinders, when one of them is at rest, can be obtained from our general solutions. Furthermore, the corresponding solutions for Newtonian fluid are also obtained as limiting cases of our general solutions.

关键词： Second grade fluid · Velocity field · Shear stress · Longitudinal oscillatory flow · Laplace and Hankel transforms