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Friction 2020年第5期8卷 905-916页

作者： Mohamed Kamal ahmed ali Xianjun HOU Mohamed AAABDELKAREEM Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Automotive and Tractors Engineering Department Faculty of EngineeringMinia UniversityEl-Minia 61111Egypt Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Owing to the significance of improving fuel economy, reducing emissions, and extending the durability of engine components, this study focused on the tribological performance of nano-additives. In this study, copper (Cu) and graphene (Gr) nanomaterials were dispersed in a fully formulated engine oil (5W-30) with different concentrations. The tribological trials were investigated under various speeds and loads, utilizing a reciprocating tribometer to mimic the ring/liner interfaces in the engine. The frictional surface morphologies were com-prehensively analyzed using electron probe X-ray microanalysis (EPMA), field emission scanning electron microscopy (FESEM), energy dispersive spectrometer (EDS), and three dimensional (3D) surface profilometry to explore the mechanisms responsible for improving the tribological performance of the frictional sliding parts in the engine. The tribological test results illustrated that lubrication by nano-additives reduced the wear rate (WR) and friction coefficient (COF) by 25%–30% and 26.5%–32.6%, respectively, as compared with 5W-30. The results showed that this is a promising approach for increasing the durability and lifespan of frictional sliding components and fuel economy in automobile engines.

关键词： engine tribology nanomaterial nanolubricant friction wear tribofilm

Quantification of Urban Sprawl for Past-To-Future in Abha City,Saudi Arabia

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 755-786页

作者： Saeed AlQadhi Javed Mallick Swapan Talukdar ahmed ali Bindajam ahmed ali A.Shohan Shahfahad Department of Civil Engineering College of EngineeringKing Khalid UniversityAbha61411Saudi Arabia Department of Geography University of Gour BangaMalda732103India Department of Architecture and Planning College of EngineeringKing Khalid UniversityAbha61411Saudi Arabia Department of Geography Faculty of Natural SciencesJamia Millia IslamiaNew Delhi110025India

Given that many cities in Saudi Arabia have been observing rapid urbanization since the 1990s,scarce studies on the spatial pattern of urban expansion in Saudi Arabia have been ***,the present study investigates the evidence of land use and land cover(LULC)dynamics and urban sprawl in Abha City of Saudi Arabia,which has been experiencing rapid urbanization,from the past to the future using novel and sophisticated *** SVM classifier was used in this study to classify the LULC maps for 1990,2000,and *** LULC dynamics between 1990–2000,2000–2018,and 1990–2018 have been analyzed using delta()change and the Markovian transitional probability *** sprawl or urban expansion was modeled using two approaches,such as landscape fragmentation and presence frequency for the first *** future LULC map for 2028 was predicted using the artificial neural network-cellular automata model(ANN-CA).Future LULC was analyzed using landscape fragmentation and frequency *** results of LULC maps showed that urban areas increased by 334.4%between 1990 and *** Delta change rate showed that 16.34%in urban areas has increased since ***,the transitional probability matrix between 1990 and 2018 reported that the built-up area is the largest stable LULC,having an 83.6%transitional probability *** 17.9%,21.8%,12.4%,and 10.5%of agricultural land,scrubland,exposed rocks,and water bodies were transformed into built-up *** sprawl models showed that 139 km^(2)of new urban areas had been set up in 2018,49 and 69 km^(2)in 1990 and ***,in 2018,more than 200%of urban areas were stabilized or became core urban *** future LULC map(2028)showed that the built-up area would be 343.72 km^(2),followed by scrubland(342.98 km^(2))and sparse vegetation(89.96 km^(2)).The new urban area in 2028 would be 169 km^(2).The authorities and planners should focus more on the sustainable development of urban areas;otherwise,it would

关键词： Urban sprawl LULC landscape fragmentation cellular automata SVM frequency approach

Ding w-Flat Modules and Dimensions

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Algebra Colloquium 2018年第2期25卷 203-216页

作者： Fuad ali ahmed Almahdi Mohammed Tamekkante Department of Mathematics Faculty of Sciences King Khalid University P. O. Box. 9004 Abha Saudi Arabia Laboratory MACS Faculty of Sciences University Moulay Ismail 5000 P.B. 11201 Zitoune Meknes Morocco

The introduction of w-operation in the class of flat modules has been successful. Let R be a ring. An R-module M is called a w-fiat module if Tor1r（M, N） is GV-torsion for all R-modules N. In this paper, we introduce the w-operation in Gorenstein homological algebra. An R-module M is called Ding w-flat if there exists an exact sequence of projective R-modules ... → P1 → P0 → p0 → p1 → ... such that M Im（P0 → p0） and such that the functor HomR （-,F） leaves the sequence exact whenever F is w-flat. Several well- known classes of rings are characterized in terms of Ding w-flat modules. Some examples are given to show that Ding w-flat modules lie strictly between projective modules and Gorenstein projective modules. The Ding w-flat dimension （of modules and rings） and the existence of Ding w-flat precovers are also studied.

关键词： w-fiat module and dimension Gorenstein projective module and dimension,strongly Gorenstein flat module

A Deep Learning Ensemble Method for Forecasting Daily Crude Oil Price Based on Snapshot Ensemble of Transformer Model

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Computer Systems Science & Engineering 2023年第7期46卷 929-950页

作者： ahmed Fathalla Zakaria Alameer Mohamed Abbas ahmed ali Department of Mathematics Faculty of ScienceSuez Canal UniversityIsmailia41522Egypt Mining and Petroleum Department Faculty of EngineeringAl-Azhar UniversityQenaEgypt School of Computer Science and Technology Central South UniversityChangshaHunanChina College of Computer Engineering and Sciences Prince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Higher Future Institute for Specialized Technological Studies Cairo3044Egypt

The oil industries are an important part of a country’s *** crude oil’s price is influenced by a wide range of ***,how accurately can countries predict its behavior and what predictors to employ are two main *** this view,we propose utilizing deep learning and ensemble learning techniques to boost crude oil’s price forecasting *** suggested method is based on a deep learning snapshot ensemble method of the Transformer *** examine the superiority of the proposed model,this paper compares the proposed deep learning ensemble model against different machine learning and statistical models for daily Organization of the Petroleum Exporting Countries(OPEC)oil price *** results demonstrated the outperformance of the proposed method over statistical and machine learning *** precisely,the proposed snapshot ensemble of Transformer method achieved relative improvement in the forecasting performance compared to autoregressive integrated moving average ARIMA(1,1,1),ARIMA(0,1,1),autoregressive moving average(ARMA)(0,1),vector autoregression(VAR),random walk(RW),support vector machine(SVM),and random forests(RF)models by 99.94%,99.62%,99.87%,99.65%,7.55%,98.38%,and 99.35%,respectively,according to mean square error metric.

关键词： Deep learning ensemble learning transformer model crude oil price

Price Prediction of Seasonal Items Using Time Series Analysis

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Computer Systems Science & Engineering 2023年第7期46卷 445-460页

作者： ahmed Salah Mahmoud Bekhit Esraa Eldesouky ahmed ali ahmed Fathalla Faculty of Computers and Informatics Zagazig UniversitySharkeya44523Egypt Information Technology Department the University of Technology and Applied SciencesIbriOman School of Electrical and Data Engineering University of Technology SydneySydney2007Australia College of Computer Engineering and Sciences Prince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Computer Science Department Faculty of Computers and InformaticsSuez Canal UniversityIsmailia41522Egypt Higher Future Institute for Specialized Technological Studies Cairo3044Egypt Department of Mathematics Faculty of ScienceSuez Canal UniversityIsmailia41522Egypt

The price prediction task is a well-studied problem due to its impact on the business *** are several research studies that have been conducted to predict the future price of items by capturing the patterns of price change,but there is very limited work to study the price prediction of seasonal goods(e.g.,Christmas gifts).Seasonal items’prices have different patterns than normal items;this can be linked to the offers and discounted prices of seasonal *** lack of research studies motivates the current work to investigate the problem of seasonal items’prices as a time series *** proposed utilizing two different approaches to address this problem,namely,1)machine learning(ML)-based models and 2)deep learning(DL)-based ***,this research tuned a set of well-known predictive models on a real-life *** models are ensemble learning-based models,random forest,Ridge,Lasso,and Linear ***,two new DL architectures based on gated recurrent unit(GRU)and long short-term memory(LSTM)models are ***,the performance of the utilized ensemble learning and classic ML models are compared against the proposed two DL architectures on different accuracy metrics,where the evaluation includes both numerical and visual comparisons of the examined *** obtained results show that the ensemble learning models outperformed the classic machine learning-based models(e.g.,linear regression and random forest)and the DL-based models.

关键词： Deep learning price prediction seasonal goods time series analysis

Preparation of Ionic Liquid-based Vilsmier Reagent from Novel Multi-purpose Dimethyl Formamide-like Ionic Liquid and Its Application

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Chinese Journal of Chemistry 2012年第7期30卷 1647-1657页

作者： Hullio,ahmed ali Mastoi,G.M. Dr.M.A Kazi Institute of Chemistry University of Sindh Jamshoro-76080Pakistan

In continuation of research to explore the applied potential of DMF-like ionic liquid, the ionic liquid version of N,N-dimethyliminiumchloride （Vilsmier reagent） has been synthesized from DMF-like ionic liquid and tested effectively for its capacity to achieve more useful organic transformations. The results show that DMF-like ionic liquid is world＇s first task specific ionic liquid which has catalyzed numerous diverse type of reaction and is multipurpose in its application. Thus a new term for this DMF-like ionic liquid has been coined that is DMF-like ＂multipurpose＂ ionic liquid.

关键词： novel concept multipurpose DMF-like ionic liquid ionic liquid-based vilsmier reagent vilsmier reagent-catalysed reactions TCT/DMF complex

Multifaceted roles of extracellular RNAs in different diseases

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Military Medical Research 2023年第3期10卷 359-368页

作者： Abdullah Muhammad Sohail Muhammad Babar Khawar ali Afzal ali Hassan Sara Shahzaman ahmed ali Molecular Medicine and Cancer Therapeutics Lab Department of ZoologyFaculty of SciencesUniversity of Central PunjabLahorePakistan Applied Molecular Biology and Biomedicine Lab Department of ZoologyUniversity of NarowalNarowalPakistan

Extracellular RNAs(exRNAs) are novel circulating factors that can be used as biomarkers in various diseases. Their unique and diverse kinds, as well as their role as biomarkers, make them significant biomarkers. There has been immense work carried out since the discovery of exRNAs in circulation and other biological fluids to catalog and determine whether exRNAs may be utilized as indicators for health and illness. In this review, we aim to understand the current state of exRNAs in relation to various diseases and their potential as biomarkers. We will also review current issues and challenges faced in using exRNAs, with clinical and lab trials, that can be used as viable markers for different diseases.

关键词： Extracellular RNAs(exRNAs) Extracellular vehicles(EVs) Cancer Biomarkers Exosomes

Synthesis and study the influence of yttrium doping on band structure,optical,non-linear optical and dielectric results for Ca_(12)Al_(14)O_(33) (C12A7) single crystals grown using traveling-solvent floating zone (TSFZ) method

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Chinese Physics B 2022年第1期31卷 626-630页

作者： A.Abdel Moez ahmed I.ali A.Tayel Solid State Physics Department Physical Research DivisionNational Research Centre(NRC)33 El Bohouth StreetDokkiGiza 12622Egypt Basic Science Department Faculty of Faculty of Technology and EducationHelwan UniversityKobry El-QopaCairo 11281Egypt

Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)*** temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot *** have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid *** structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was *** results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.

关键词： syntheses Ca_(12)Al_(14)O_(33)(C12A7)single crystals Y-doping optical parameters dielectric results nonlinear optical susceptibility

Slicing-Based Enhanced Method for Privacy-Preserving in Publishing Big Data

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Computers, Materials & Continua 2022年第8期72卷 3665-3686页

作者： Mohammed BinJubier Mohd Arfian Ismail Abdulghani ali ahmed ali Safaa Sadiq Faculty of Computing Universiti Malaysia PahangKuantanPahangMalaysia School of Computer Science and Informatics De Montfort UniversityLeicesterLE19BHUnited Kingdom School of Engineering Computing and Mathematical SciencesUniversity of WolverhamptonWulfruna Street WolverhamptonWV11LYUnited Kingdom

Publishing big data and making it accessible to researchers is important for knowledge building as it helps in applying highly efficient methods to plan,conduct,and assess scientific ***,publishing and processing big data poses a privacy concern related to protecting individuals’sensitive information while maintaining the usability of the published *** anonymization methods,such as slicing and merging,have been designed as solutions to the privacy concerns for publishing big ***,the major drawback of merging and slicing is the random permutation procedure,which does not always guarantee complete protection against attribute or membership ***,merging procedures may generatemany fake tuples,leading to a loss of data utility and subsequent erroneous knowledge *** study therefore proposes a slicingbased enhanced method for privacy-preserving big data publishing while maintaining the data *** particular,the proposed method distributes the data into horizontal and vertical *** lower and upper protection levels are then used to identify the unique and identical attributes’*** unique and identical attributes are swapped to ensure the published big data is protected from disclosure *** outcome of the experiments demonstrates that the proposed method could maintain data utility and provide stronger privacy preservation.

关键词： Big data big data privacy preservation anonymization data publishing

Abundance,spatial distribution,and physical characteristics of microplastics in stormwater detention ponds

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Frontiers of Environmental Science & Engineering 2023年第10期17卷 75-87页

作者： Muhammad Masood Ashiq Farhad Jazaei Kati Bell ahmed Shakir ali ali alireza Bakhshaee Peyman Babakhani Department of Civil Engineering University of MemphisMemphisTN 38152USA Brown and Caldwell NashvilleTN 37228USA Earth Surface Science Institute School of Earth and EnvironmentUniversity of LeedsLeedsLS29JTUK

Despite extensive research on microplastics (MP) in marine environments, little is known about MP abundance and transport in terrestrial systems. There is, therefore, still little understanding of the main mechanisms driving the substantial transport of MP across different environmental compartments. Storm events can transport MP beyond boundaries, such as from the land to groundwater or the ocean, as has already been discovered for organic carbon transport. Urban stormwater detention ponds are suitable environments to study the impact of stormwater on the environmental fate and transport of MP. Herein, we investigate the longitudinal and vertical distribution of MP within two detention ponds with different physical characteristics. Soil samples were collected at various locations and from multiple depths (surface and subsurface layers) for measuring MP concentrations using fluorescence microscopy. Our findings show that MP are retained more near the inlet of the ponds, and MP of larger sizes were found more abundantly near inlets than outlets. We also found that MP mass and sizes decrease from surface soil to subsurface soil. In the pond, where vegetation (grass root network) was more considerable, MP were found more evenly distributed along the depth. In terms of shape, the fragments were the most abundant MP shape.

关键词： Microplastic Environmental transport Soil pollution Stormwater Detention ponds