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Spatial distribution of trace elements associated with organic carbon along the Beiyun River basin, Beijing, China

International Journal of Sediment Research 2022年第3期37卷 335-345页

作者： farhan Iftikhar Shiliang Liu Yongxiu Sun Yixuan Liu Muhammad Imran School of Environment State Key Laboratory of Water Environment Simulation Beijing Normal University Department of Soil and Environmental Science Ghazi University Key Laboratory of Soil Resource & Biotech Application Shaanxi Academy of Sciences Xi'an Botanical Garden of Shaanxi Province Institute of Botany of Shaanxi Province

Pollution resulting from terrestrial and aquatic trace elements has become a severe problem across the world. Organic carbon(OC) content has a high affinity for metallic contaminants and it acts as a significant sink for trace elements. The decomposition of OC content directly influences the bioavailability of trace elements. The decomposition of OC content and OC distribution vary spatially, these processes affect the release of trace elements and need further research. In the current study, sediment samples from the surface sediment along Beiyun River(Section 1 to Section 4 from upper to lower reaches),which is situated in the rapidly urbanized Beijing metropolis, were measured for OC, moisture, hardness,and trace elements. The OC contents were found to have a substantial difference among all four river sections along the urbanized river gradient. Whereas the higher OC contents were found in Sections 2(Urbanized uplands) and 3(farmland) compared to those in Sections 1(forest) and 4(farmland and part of constructed areas). On the other hand, the highest value of the correlation coefficient was found among the different values of trace elements and OC content in the riverine zone of the Beiyun River basin. OC contents play a vital role in the transformation and origin of trace elements in the surface sediment of the Beiyun River basin. The One-way Analysis of Variance(ANOVA) was applied to compare the means of OC and trace elements at different sections indicating no significant difference. However,source identification of trace elements indicated that a geogenic source was responsible for higher contents of As and(69.95%). Simultaneously, the natural OC, agricultural activities, and industrial waste contributed about(21.10%) towards the Cd and Zn, and about 10% for Cr and Cu. The current study concludes that the absolute principle component analysis-multiple linear regression(APCA-MLR)method can be successfully used to investigate the trace elements(Zn, Ni, Pb, Mn,

关键词： Organic carbon content Trace element Spatial distribution Source apportionment Absolute principle component analysis–multiple linear regression (APCA-MLR)

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Numerical Solution of a Problem of Thermal Stresses of a Magnetothermoelastic Cylinder with Rotation by Finite-Difference Method

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Computers, Materials & Continua 2021年第9期68卷 3339-3352页

作者： F.S.Bayones A.M.Abd-Alla A.M.farhan Department of Mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Mathematics Faculty of ScienceSohag UniversityEgypt Physics Department Faculty of ScienceJazan UniversityJazanSaudi Arabia Physics Department Faculty of ScienceZagazig UniversityZagazigEgypt

The present article deals with the investigation thermal stress of a magnetothermoelastic cylinder subjected to rotation,open or closed circuit,thermal and mechanical boundary *** outer and inner surfaces of the cylinder are subjected to both mechanical and thermal boundary conditions.A The transient coupled thermoelasticity in an infinite cylinder with its base abruptly exposed to a heat flux of a decaying exponential function of time is devised solve by the finite-difference *** fundamental equations’system is solved by utilizing an implicit finite-difference *** current method is a second-order accurate in time and space;it is also unconditionally *** illustrate the present model’s efficiency,we consider a suitable material and acquire the numerical solution of temperature,displacement components,and the components of stresses with time t and through the radial of an infinite *** results indicate that the effect of coupled thermoelasticity,magnetic field,and rotation on the temperature,stresses,and displacement is quite *** order to illustrate and verify the analytical developments,the numerical solution of partial differential equations,stress components,displacement components and temperature is carried out and computer simulated results are presented *** study is helpful in the development of piezoelectric devices.

关键词： Thermoelasticity thermal stress finite-difference method non-homogeneous material rotation magnetic field

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Pulse width modulation voltage source deadtime effect on partial discharge and lifetime of inverter‐fed motor insulation

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High Voltage 2022年第6期7卷 1185-1193页

作者： Shakeel Akram Peng Wang Pengfei Meng Gian Carlo Montanari farhan Hameed Malik College of Electrical Engineering Sichuan UniversityChengduChina Center for Advanced Power Systems Florida State UniversityTallahasseeFloridaUSA Department of Electromechanical Engineering Abu Dhabi PolytechnicAbu DhabiUnited Arab Emirates

This paper analyses the impact of square wave pulse voltage deadtime on the partial discharge(PD)and the lifetime of turn-to-turn insulation.A bipolar repetitive pulse voltage with a deadtime of 0–10μs is produced using double half-bridge solid-state switches having push–pull technology controlled by a field-programmable gate *** mechanism of the discharge process at rising and falling edges of the pulse voltage before and after deadtime is analysed in *** discharge amplitude and PD probability at the rising/falling edges of the voltage waveform increase as the deadtime increases from 0 to 10μs due to the remanent *** number of PD and their intensity is higher at the first rising/falling edges of pulse voltage as compared to the second rising/falling edges for all deadtimes 0–10μ*** the deadtime increases beyond 2μs,the number of PDs increases and concentrates at a specific phase angle of rising/falling *** localise discharges degrade the insulation material and reduce its *** study helps to identify the inverter-fed motor insulation faults due to *** can provide guidelines to motor insulation designers to determine the limit value of deadtime to compensate PD and ensure the safer operation of such motors.

关键词： dead insulation inverter

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Multi-Waves,Breathers,Periodic and Cross-Kink Solutions to the(2+1)-Dimensional Variable-Coefficient Caudrey-Dodd-Gibbon-Kotera-Sawada Equation

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Journal of Ocean University of China 2021年第1期20卷 35-44页

作者： LIU Dong JU Xiaodong ILHAN Onur Alp MANAFIAN Jalil ISMAEL Hajar farhan State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China China Petroleum Materials Company Limited Beijing 100029China Department of Mathematics Erciyes UniversityMelikgazi-Kayseri 38039Turkey Department of Applied Mathematics Faculty of Mathematical SciencesUniversity of TabrizTabriz ***Iran Department of Mathematics Faculty of ScienceUniversity of ZakhoZakho 42002Iraq

The present article deals with multi-waves and breathers solution of the(2+1)-dimensional variable-coefficient CaudreyDodd-Gibbon-Kotera-Sawada equation under the Hirota bilinear operator *** obtained solutions for solving the current equation represent some localized waves including soliton,solitary wave solutions,periodic and cross-kink solutions in which have been investigated by the approach of the bilinear ***,by choosing specific parameter constraints in the multi-waves and breathers,all cases the periodic and cross-kink solutions can be captured from the 1-and *** obtained solutions are extended with numerical simulation to analyze graphically,which results in 1-and 2-soliton solutions and also periodic and cross-kink solutions *** will be extensively used to report many attractive physical phenomena in the fields of acoustics,heat transfer,fluid dynamics,classical mechanics,and so *** have shown that the assigned method is further general,efficient,straightforward,and powerful and can be exerted to establish exact solutions of diverse kinds of fractional equations originated in mathematical physics and *** have depicted the figures of the evaluated solutions in order to interpret the physical phenomena.

关键词： variable-coefficient Caudrey-Dodd-Gibbon-Kotera-Sawada equation Hirota bilinear operator method soliton multi-waves and breathers periodic and cross-kink solitray wave solutions

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An Empirical Study on Attention Factors to Massive Open Online Courses

An Empirical Study on Attention Factors to Massive Open Onli...

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作者： Muhammad farhan Mughal 华中师范大学

学位级别：硕士

随着时代的进步,日新月异的科技不但改变了人们的生活与出行的方式,甚至改变了人们的思考方式。科技的进步不仅体现在各个领域,其对教育与治学方法也影响深远。因此,研究各种科技辅助技术如何提升高校知识传递效益具有重要意义。不管是... 详细信息

随着时代的进步,日新月异的科技不但改变了人们的生活与出行的方式,甚至改变了人们的思考方式。科技的进步不仅体现在各个领域,其对教育与治学方法也影响深远。因此,研究各种科技辅助技术如何提升高校知识传递效益具有重要意义。不管是现在或将来,科技势必对高校带来变革。信息技术的应用对高校教育已带来广泛的影响,这也是为什么需要关注科技如何促进高校教学与改进学习方式的原因。每当论及高教的未来发展趋势时,出于学术潜力与技能的考量,“大规模开放式在线课程”(MOOCs)往往被视为是新一波的教育革命为了研究MOOCs的实践及任何影响其实践的原因,本研究的目的是在技术准备和科技接受模型框架之下,检视学生使用MOOCs系统的动机,并且理解何种因素将影响学生对该系统的接纳。这项研究的主要是要找出能提升个人使用MOOCs意愿的原因。本研究结合技术准备指数模式(TRI)与技术接受模式(TAM),探讨影响MOOCs采用的因素。在TRI和TAM的基础之上,本研究编制了一份包含35个问题的调查问卷,从巴基斯坦的学生群中收集研究数据。本研究的数据样本为237份,并且从中得到了不同的假设。研究模型解释了MOOCs的使用者意向出现很大的差异。结果表明,TRI模型的两个因素,即个人创新和乐观性与MOOCs的认知易用性(PEU)以及认知实用性(PU)呈正相关。另外两个维度,即不安全感和不适感对PEU及PU产生了负面影响。然而,不安全感的负面影响不显著,而不适感对PU与PEU有着更显著的影响。此外,在TAM模式的基本命题下,本研究还肯定PEU对PU有着正面的影响,进而促使PU对使用MOOCs意愿产生积极影响。

关键词：教育科技大规模开放在线课程技术准备技术接受意愿认知实用性认知易用性

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Termites and Chinese agricultural system: applications and advances in integrated termite management and chemical control

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Insect Science 2021年第1期28卷 2-20页

作者： farhan Ahmad Hatem Fouad Shi-You Liang Yin Hu Jian-Chu Mo Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests Institute of Insect SciencesCollege of Agricultural and BiotechnologyZhejiang UniversityHangzhouChina Entomology Section Central Cotton Research InstituteSakrandShaheed BenazirabadSindhPakistan Department of Field Crop Pests Plant Protection Research InstituteAgricultural Research CentreCairoEgypt National Termite Control Center HangzhouChina Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of Insect SciencesCollege of Agriculture and BiotechnologyZhejiang UniversityYuhangtang Road 866Hangzhou 310058China

Termites are eusocial arthropod decomposers,and improve soil fertility,crop yield,and also are used by humans for their ben efits across the ***,some species of termites are becoming a threat to the farming community as they are directly and indirectly causing major losses to the agricultural *** is estimated that termites cost the global economy more than 40 billion USD annually,and considerable research has been done on their *** this review,we present the available information related to sustainable and integrated termite management practices(ITM).Furthermore,we insist that the better management of this menace can be possible through:(i)improving traditional methods to keep termites away from crops;(ii)improving agricultural practices to maintain plants with more vigor and less susceptible to termite attack;and(iii)integration of available techniques to reduce termite infestation in crops and *** application of an effective combination of traditional practices with recently developed approaches is the best option for agricultural ***,keeping in mind the beneficial nature of this pest,more innovative efforts for its management,particularly using rapidly emerging technology(e.g.,RNA interference),are needed.

关键词： entomopathogens geographical distribution integrated termite management termite

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An Intelligent Cluster Optimization Algorithm for Smart Body Area Networks

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Computers, Materials & Continua 2021年第6期67卷 3795-3814页

作者： Adil Mushtaq Muhammad Nadeem Majeed farhan Aadil Muhammad Fahad Khan Sangsoon Lim Department of Software Engineering University of Engineering and TechnologyTaxilaPakistan Department of Computer Science COMSATS University IslamabadAttock CampusPakistan Department of Computer Engineering Sungkyul UniversityAnyang430010Korea

Body Area Networks(BODYNETs)or Wireless Body Area Networks(WBAN),being an important type of ad-hoc network,plays a vital role in multimedia,safety,and traffic management *** BODYNETs,rapid topology changes occur due to high node mobility,which affects the scalability of the *** clustering is one mechanism among many others,which is used to overcome this issue in *** are many clustering algorithms used in this domain to overcome this ***,these algorithms generate a large number of Cluster Heads(CHs),which results in scarce resource utilization and degraded *** this research,an efficient clustering technique is proposed to handle these *** transmission range of BODYNET nodes is dynamically tuned accordingly as per their operational *** optimizing the transmission range,the packet loss ratio is minimized,and link quality is improved,which leads to reduced energy *** select optimal CHs the Whale Optimization Algorithm(WOA)is used based on their fitness,which enhances the network performance by reducing routing *** proposed scheme outclasses the existing state-of-the-art techniques,e.g.,Ant Colony Optimization(ACO),Gray Wolf Optimization(GWO),and Dragonfly Optimization Algorithm(DFA)in terms of energy consumption and cluster building time.

关键词： Bodynets WBAN clustering ad-hoc networks whale optimizer artificial neural networks intelligent transportation system

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An Efficient Method for Underwater Video Summarization and Object Detection Using YoLoV3

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Intelligent Automation & Soft Computing 2023年第2期35卷 1295-1310页

作者： Mubashir Javaid Muazzam Maqsood farhan Aadil Jibran Safdar Yongsung Kim Department of Computer Science UETTaxilaPakistan Department of Computer Science COMSATS University IslamabadAttock CampusAttockPakistan Department of Technology Education Chungnam National UniversityDaejeon34134Korea

Currently,worldwide industries and communities are concerned with building,expanding,and exploring the assets and resources found in the oceans and *** precisely,to analyze a stock,archaeology,and surveillance,sev-eral cameras are installed underseas to collect ***,on the other hand,these large size videos require a lot of time and memory for their processing to extract relevant ***,to automate this manual procedure of video assessment,an accurate and efﬁcient automated system is a greater *** this perspective,we intend to present a complete framework solution for the task of video summarization and object detection in underwater *** employed a perceived motion energy(PME)method toﬁrst extract the keyframes followed by an object detection model approach namely YoloV3 to perform object detection in underwater *** issues of blurriness and low contrast in underwater images are also taken into account in the presented approach by applying the image enhancement ***,the suggested framework of underwater video summarization and object detection has been evaluated on a publicly available brackish *** is observed that the proposed framework shows good performance and hence ultimately assists several marine researchers or scientists related to theﬁeld of underwater archaeology,stock assessment,and surveillance.

关键词： Computer vision deep learning digital image processing underwater video analysis video summarization object detection YOLOV3

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Solution of a problem of thermal stresses in a non-homogeneous thermoelastic infinite medium of isotropic material by finite difference method

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Journal of Ocean Engineering and Science 2019年第3期4卷 256-262页

作者： A.M.farhan A.M.Abd-Alla Moaiad A.Khder Physics Department Faculty of ScienceJazan UniversitySaudi Arabia Physics Department Faculty of ScienceZagzig UniversityEgypt Mathematics Department Faculty of ScienceSohag UniversityEgypt Department of Computer Science Applied Science UniversityBahrain

The present work deals with a new problem of thermoelasticity for an infinitely long and isotropic circular cylinder of temperature dependent physical *** inner and outer curved surfaces of the cylinder are subjected to both the mechanical and thermal boundary conditions.A finite difference model is developed to derive the solution of the problem in which the governing equations are uncoupled linear partial differential *** transient solution at any time can be evaluated directly from the *** order to demonstrate the efficiency of the present model we consider a suitable material and obtain the numerical solution of displacement,temperature,and stresses inside the cylinder for the homogeneous-dependent material properties of the *** results are analyzed with the help of different graphical plots.

关键词： Thermal stress Thermoelasticity Wave propagation Finite difference Method Non-homogeneous medium

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Detection of Copy-Move Forgery in Digital Images Using Singular Value Decomposition

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Computers, Materials & Continua 2023年第2期74卷 4135-4147页

作者： Zaid Nidhal Khudhair farhan Mohamed Amjad Rehman Tanzila Saba Saeed Ali bahaj Faculty of Engineering School of ComputingUniversity Technology of MalaysiaJohar BahruMalaysia UTM-IRDA MaGICX Institute of Human Centered EngineeringUniversiti Teknologi MalaysiaMalaysia Artificial Intelligence&Data Analytics Lab CCIS Prince Sultan University Riyadh Saudi Arabia Computer Techniques Engineering Department Faculty of Information TechnologyImam Ja’afar Al-Sadiq UniversityBaghdadIraq

This paper presents an improved approach for detecting copy-move forgery based on singular value decomposition(SVD).It is a block-based method where the image is scanned from left to right and top to down by a sliding window with a determined *** each step,the SVD is ***,the diagonal matrix’s maximum value(norm)is selected(representing the scaling factor for SVD and a fixed value for each set of matrix elements even when rotating thematrix or scaled).Then,the similar norms are grouped,and each leading group is separated into many subgroups(elements of each subgroup are neighbors)according to 8-adjacency(the subgroups for each leading group must be far from others by a specific distance).After that,a weight is assigned for each subgroup to classify the image as forgery or ***,the F1 score of the proposed system is measured,reaching 99.1%.This approach is robust against rotation,scaling,noisy images,and illumination *** is compared with other similarmethods and presents very promised results.

关键词： Forgery image forensic image processing region duplication SVD transformation technological development

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