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Communications in Theoretical Physics 2021年第2期73卷 11-22页

作者： Nermeen A Elkot Mahmoud A Zaky Eid H Doha ibrahem g ameen Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Applied Mathematics National Research CentreDokkiCairo 12622Egypt Department of Mathematics Faculty of ScienceAl-Azhar UniversityCairoEgypt

While the approximate solutions of one-dimensional nonlinear Volterra-Fredholm integral equations with smooth kermels are now well understood,no systematic studies of the numerical solutions of their multi-dimensional counterparts *** this paper,we provide an efficient numerical approach for the multi-dimensional nonlinear Volterra-Fredholm integral equations based on the multi-variate Legendre-collocation *** collocation methods for multi-dimensional nonlinear integral equations are known to cause major difficulties from a convergence analysis point of ***,rigorous error estimates are provided in the weighted Sobolev space showing the exponential decay of the numerical *** existence and uniqueness of the numerical solution are *** experiments are provided to support the theoretical convergence *** results indicate that our spectral collocation method is more flexible with better accuracy than the existing ones.

关键词： spectral collocation method convergence analysis multi-dimensional integral equations

Finite element analysis of dynamic stability of skeletal structures under periodic loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 245-256页

作者： THANA Hemantha Kumar ameen Mohammed Department of Civil Engineering National Institute of Technology Calicut Kerala 673601 India

This paper addresses the dynamic stability problem of columns and frames subjected to axially applied periodic loads. Such a structure can become unstable under certain combinations of amplitudes and frequencies of the imposed load acting on its columns/beams. These are usually shown in the form of plots which describe regions of instability. The finite element method (FEM) is used in this work to analyse dynamic stability problems of columns. Two-noded beam elements are used for this purpose. The periodic loading is decomposed into various harmonics using Fourier series expansion. Computer codes in C++ using object oriented concepts are developed to determine the stability regions of columns subjected to periodic loading. A number of nu-merical examples are presented to illustrate the working of the program. The direct integration of the equations of motions of the discretised system is carried out using Newmark’s method to verify the results.

关键词： Finite element analysis Dynamic stability Mathieu-Hill equation

Chromaticity of Complete 6-Partite graphs with Certain Star or Matching Deleted Ⅱ

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 35-42页

作者： Roslan Hasni ameen Shaman ameen Yee-Hock Peng Hai-xing Zhao School of Mathematical Sciences Universiti Sains Malaysia Department of Mathematics and Institute for Mathematical Research University Putra Malaysia Department of Mathematics Qinghai Normal University

Let P（g, λ） be the chromatic polynomial of a graph g. Two graphs g and H are said to be chromatically equivalent, denoted g N H, if P（g, λ） = P（H, λ）. We write [g] = {HIH - g}. If [g] = {g}, then g is said to be chromatically unique. In this paper, we first characterize certain complete 6-partite graphs with 6rid＋1 vertices according to the number of 7-independent partitions of g. Using these results, we investigate the chromaticity of g with certain star or matching deleted. As a by-product, many new families of chromatically unique complete 6-partite graphs with certain star or matching deleted are obtained.

关键词： chromatic polynomial chromatically closed chromatic uniqueness

Synthesis of thiopyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]furo[3,2-d]pyrimidines

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Chinese Chemical Letters 2010年第6期21卷 669-673页

作者： Essam Kh. Ahmed Mohamed A. ameen Chemistry Department Faculty of ScienceEl Minia UniversityEl Minia 61519Egypt

Reactions of the 6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrile derivative 1 withα-halo-carbonyl compounds gave the ortho-substituted intermediates 2a-c which were converted into furo[2,3-b]thiopyrano[4,3-d]pyridines 3a-c by fusion of a furan moiety under basic *** cyclization of 3a-c led to a fusion of a pyrimidine ring,yielding the tetracyclic products 6,7 and *** addition,condensation of 6 with various aromatic aldehydes afforded the corresponding imines 9a,*** reaction of 7 gave products 10a,b.

关键词： S N-Heterocycles S N O-Heterocyles Furo[2 3-b]thiopyrano[4 3-d]pyridine Thiopyranopyridofuropyrimidines

Membrane Fouling in Microfiltration of Sanitary Landfill Leachate for Removals of Colourand Solids

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应用与环境生物学报 2013年第1期19卷 184-188页

作者： Emad S.M.ameen Water Research Alliance Institute of Environmental and Water Resource ManagementFaculty of Civil EngineeringUniversiti Teknologi Malaysia

In this research,the treatability of solids from sanitary landfill leachate by microfiltration membrane was investigated and the fouling of the membrane was carefully *** microfiltration process was carried out for 21 h in experimental system involved coagulation with Moringa oleifera followed by filtration using submerged hollow fibre microfiltration membrane (MFM).Coagulation with ***,air diffusers and back flush technique were used for preventing or alleviating fouling of the *** hollow fibre MFM showed high removals of 98%,91% and 99% for turbidity,colour and total suspended solids *** was obtained at the beginning of the ***,quality of the filtrate rapidly declined during the filtration *** was found to proceed according to the classical cake filtration *** with *** as well as the back-flush technique could not fully restore the deterioration occurred to the membrane.

关键词： RAPD ISSR AFLP 环境生物学

Changes in soil temperature and water content under mobile soil steam disinfection

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International Journal of Agricultural and Biological Engineering 2021年第3期14卷 140-147页

作者： Zhenjie Yang Xiaochan Wang Muhammad ameen College of Engineering Nanjing Agricultural UniversityNanjing 210031China College of Mechanical and Electrical Engineering Yunnan Agricultural UniversityKunming 650201China

The soil steam injection method is one of the most effective disinfection methods,and the determination of the steam pipe structure parameters is very *** steam capillary diameter(SCD)affects the steam flow field in each pipe,which in turn affects the steam changes in the soil flow range and soil temperature(ST).Larger SCD would make lower ST in clay loam,silt loam,and sandy clay *** effectiveness of an SCD of 10 mm was verified by a mobile disinfection test at walking speeds of 10 cm/min and 30 cm/min under soil water content(SWC)of 15%and 35%,*** results showed that when the walking speed was 10 cm/min,the initial SWC was proportional to the ***,when the walking speed was 30 cm/min,the law was exactly the opposite;that is,the initial water content is inversely proportional to the *** research can provide a theoretical research foundation for increasing soil temperature for efficient soil steam disinfection.

关键词： soil steam disinfection steam capillary diameter steam capillary vent soil temperature soil water content

Internet of Things (IoT) Security Enhancement Using Xgboost Machine Learning Techniques

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Computers, Materials & Continua 2023年第10期77卷 717-732页

作者： Dana F.Doghramachi Siddeeq Y.ameen Department of Information Systems Engineering Techniques Erbil Technical Engineering CollegeErbil Polytechnic UniversityErbil44001Iraq Department of Energy Engineering Technical College of EngineeringDuhok Polytechnic UniversityDuhok42001Iraq

The rapid adoption of the Internet of Things(IoT)across industries has revolutionized daily life by providing essential services and leisure ***,the inadequate software protection in IoT devices exposes them to cyberattacks with severe *** Detection Systems(IDS)are vital in mitigating these risks by detecting abnormal network behavior and monitoring safe network *** security research community has shown particular interest in leveraging Machine Learning(ML)approaches to develop practical IDS applications for general cyber networks and IoT ***,most available datasets related to Industrial IoT suffer from imbalanced class *** study proposes a methodology that involves dataset preprocessing,including data cleaning,encoding,and *** class imbalance is addressed by employing the Synthetic Minority Oversampling Technique(SMOTE)and performing feature reduction using correlation *** ML classifiers,including Logistic Regression,multi-layer perceptron,Decision Trees,Random Forest,and XgBoost,are employed to model IoT *** effectiveness and robustness of the proposed method evaluate using the IoTID20 dataset,which represents current imbalanced IoT *** results highlight that the XgBoost model,integrated with SMOTE,achieves outstanding attack detection accuracy of 0.99 in binary classification,0.99 in multi-class classification,and 0.81 in multiple *** findings demonstrate our approach’s significant improvements to attack detection in imbalanced IoT datasets,establishing its superiority over existing IDS frameworks.

关键词： IoT detection system machine learning SMOTE Xgboost

A Pseudo-Spectral Scheme for Systems of Two-Point Boundary Value Problems with Left and Right Sided Fractional Derivatives and Related Integral Equations

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Computer Modeling in Engineering & Sciences 2021年第7期128卷 21-41页

作者： I.g.ameen N.A.Elkot M.A.Zaky A.S.Hendy E.H.Doha Department of Mathematics Faculty of ScienceAl-Azhar UniversityCairoEgypt Department of Mathematics Faculty of ScienceCairo UniversityGiza12613Egypt Department of Applied Mathematics Physics DivisionNational Research CentreDokkiCairo12622Egypt Department of Computational Mathematics and Computer Science Institute of Natural Sciences and MathematicsUral Federal UniversityYekaterinburg620002Russia Department of Mathematics Faculty of ScienceBenha UniversityBenha13511Egypt

We target here to solve numerically a class of nonlinear fractional two-point boundary value problems involving left-and right-sided fractional *** main ingredient of the proposed method is to recast the problem into an equivalent system of weakly singular integral ***,a Legendre-based spectral collocation method is developed for solving the transformed ***,we can make good use of the advantages of the gauss quadrature *** present the construction and analysis of the collocation *** results can be indirectly applied to solve fractional optimal control problems by considering the corresponding Euler–Lagrange *** numerical examples are given to confirm the convergence analysis and robustness of the scheme.

关键词： Spectral collocation method weakly singular integral equations two-point boundary value problems convergence analysis

Comprehensive analysis of glacier recession(2000-2020)in the Nun-Kun group of glaciers,Northwestern Himalaya

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Journal of Mountain Science 2024年第3期21卷 768-785页

作者： Shakil Ahmad ROMSHOO Ummer ameen Mustafa Hameed BHAT Tariq ABDULLAH Department of geoinformatics University of KashmirSrinagarKashmir 190006India Islamic University of Science and Technology AwantiporaKashmir 192122India Centre of Excellence for glacier Studies in the Western Himalaya University of KashmirSrinagarKashmir 190006India

Himalayan glaciers are shrinking rapidly,especially after *** shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger *** this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun group of glaciers(NKgg),were investigated using Landsat satellite data during *** in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field *** study revealed that the NKgg glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation *** the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and *** observed mass loss of the NKgg has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in *** ELA has shifted upwards by 83.0±22 m during the *** morphological and topographic factors showed a strong influence on glacier ***,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger *** debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKgg during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin.

关键词： Nun-Kun range glacier recession glacier snout Remote Sensing Himalaya glacier velocity

Combined impacts of bioaugmentation and vermiremediation on crude oil-contaminated soil: Mitigating strategies for prospective environmental management

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Emerging Contaminants 2024年第2期10卷 123-134页

作者： Fuad ameen Ali A.Al-Homaidan Department of Botany&Microbiology College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

This study aimed to address the remediation of crude oil-contaminated soil by employing four different factorial setups:I-used the earthworms(Eudrilus eugeniae)for vermiremediation,II–utilized the bacteria(Pseudomonas aeruginosa FA-7)for bioaugmentation,III–combined earthworms+bacteria to perform vermiremediation+bioaugmentation,and IV–served as abiotic ***,garden soil weighing 1 kg and 50 g of desiccated cow dung were introduced into the experimental groups and abiotic ***,different quantities of crude oil ranging from 5 to 20 mL were *** on the results,from 5 mL of oil-contaminated soil,the factorial setup-III removed the maximum proportion of total petroleum hydrocarbons(TPH)in V+B1(58.06%).The abiotic control treatments AC1(1.11%)exhibited the lowest TPH removal *** bioremediated soil had significantly(Pganic carbon(44.03%),total nitrogen(42.42%),total phosphorus(52.17%),and total potassium(22.64%)by the end of the *** the 60th day of factorial setup-III,the bacterial population(386.470±0.432 CFU×10^(6) g^(−1)),actinomycetes(188.043±0.246 CFU×10^(8) g^(−1)),and fungi(16.603±0.202 CFU×10^(5) g^(−1))were *** germination rates of Trigonella foenum-graecum seeds were increased by 86.6%in factorial setup III(V+B1)when compared to other factorial ***,the incorporation of vermiremediation and bioaugmentation provides a distinctive platform for effective oil-contaminated soil remediation.

关键词： Crude oil Eudrilus eugeniae Pseudomonas aeruginosa FA-7 Bioremediation Seed germination