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Automated measurement of moving grains on bed deposits

International Journal of Sediment Research 2011年第3期26卷 304-317页

作者： amir h.n.chegini Simon TAIT Lecturer of Civil Engineering Department Faculty of EngineeringUniversity of GuilanMain CampusI.R.of Iran School of Engineering Design and TechnologyUniversity of BradfordBradfordBD7 1DPUK.

The performance of gravel bedload predictor equations is particularly poor.A key reason for this situation is the current poor understanding of the physical mechanisms that are involved in the entrainment of grains from water-worked sediment *** has been caused,in part,by a lack of detailed data on the behaviour of moving sediment *** this study,observations of the entrainment, transport and deposition of many particles from a gravel bed has been collected and studied using an image-based *** system was used to measure the motion of hundreds of gravel particles moving as *** paper describes the development of the image-based system and the data processing methods used to provide the automated measurement of particle *** system was adapted from commercially available PIV equipment and was configured to obtain simultaneously data for the analysis of the moving grains and the near-bed flow *** techniques developed are relatively sensitive to sediment colour and shape by using related image processing algorithms and so could be applied to natural gravel *** results(image data)obtained from the techniques developed are amended in a program by using two functions(commands)of image processing called "Label2RGB",and "RegionProps" which distinguish the colour and shape of moving sediment grains *** data processing provided information that identified individual grain entrainments,*** accurately traced the motion of some,but not all,*** show that the system was able to estimate grain entrainment rates and indicate locations of preferential entrainment and deposition from data on hundreds of individual moving grains.

关键词： Uniform flow Bed load Sediment transport Measurement Image processing

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Uniform and graded bed-load sediment transport in a degrading channel with non-equilibrium conditions

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International Journal of Sediment Research 2020年第2期35卷 115-124页

作者： Khabat Khosravi amir h.n.chegini James R.Cooper Prasad Daggupati Andrew Binns Luca Mao School of Engineering University of Guelph School of the Built Environment Heriot-Watt University Department of Geography and Planning School of Environmental SciencesUniversity of Liverpool Department of Geography University of Lincoln

Bed-load transport plays a critical role in river morphological change and has an important impact on river *** there is good understanding of the role of the variation of river bed grain size on transport dynamics in equilibrium conditions,much less is understood for non-equilibrium conditions when the channel is either aggrading or *** particular,the relative role of different grain sizes in the promotion and hindering of the transport of coarse and fine fractions in a degrading channel has yet to be *** current study attempts to provide new understanding through a series of flume experiments done using uniform and graded sediment *** experiments revealed coarser grain-size fractions for a poorly-sorted sediment,relative to uniform-sized sediment,reduced the transport of finer grains and finer fractions enhanced the transport of coarse *** hinderingpromotion effect,caused by relative hiding and exposure of finer and coarse fractions,increased with bed slope and decreased with relative *** particular,as relative submergence increased,the graded fractions tended towards behaving more like their unifo rm-sized ***,the bed-load parameter of the graded fractions increased more with a rise in bed slope than observed for the uniformsized *** results revealed,for degrading channel conditions,such as downstream of a dam,bed-load equations developed for uniform bed sediment are inappropriate for use in natural river systems,particularly in mountain ***,changes in river bed composition due to activities that enhance the input of hill-slope sediment,such as fire,logging,and agricultural development,are likely to cause significant changes in river morphology.

关键词： Graded sediment Exposure hiding Flume experiments non-equilibrium

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Synergistic effect of adsorption and photocatalytic degradation of oilfield-produced water by electrospun photocatalytic fibers of Polystyrene/nanorod-Graphitic carbon nitride

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Journal of Environmental Sciences 2024年第7期141卷 287-303页

作者： Parisa Azmoon Mehrdad Farhadian Alireza Pendashteh amir h.navarchian Department of Chemical Engineering Faculty of EngineeringUniversity of IsfahanIsfahanIran Department of Chemical Engineering Faculty of EngineeringUniversity of GuilanRashtIran Department of Water and Environmental Engineering Caspian Sea Basin Research CenterUniversity of GuilanRashtIran

Graphitic carbon nitride with nanorod structure(nr-GCn)was synthesized using melamine as a precursor without any other reagents by hydrothermal pretreatment ***,FTIR,SEM,n_(2)adsorption-desorption from BET,UV-Vis DRS spectroscopy,and photoluminescence were used to characterize the prepared ***,the photoelectrochemical behavior of nanoparticles was studied by photocurrent transient response and cyclic voltammetry ***(PS)fibrous mat was fabricated by electrospinning technique and used as a support for the stabilization of the *** performance of the synthesized nanoparticles and photocatalytic fibers(PS/nr-GCn)was evaluated in oilfield-produced water treatment under visible light *** this process,oil contaminants were adsorbed by hydrophobic polystyrene fibers and simultaneously degraded by *** removal efficiency of chemical oxygen demand(COD)has been obtained 96.6%and 98.4%by nr-GCn and PS/nr-GCn,respectively,at the optimum conditions of ph4,photocatalyst dosage 0.5 g/L,COD initial concentration 550 mg/L,and illumination time 150 *** gas chromatography-mass spectroscopy analysis results showed 99.3%removal of total petroleum hydrocarbons using photocatalytic fibers of PS/*** results demonstrated that the GCn has outstanding features like controllable morphology,visible-light-driven,and showing high potential in oily wastewater ***,the synergistic effect of adsorption and photocatalytic degradation is an effective technique in oilfield-produced water treatment.

关键词： Graphitic carbon nitride(GCn) nanorod structure Polystyrene fibrous mat Photocatalytic fibers Oilfield-produced water(OPW)

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Prediction of vertical displacement for a buried pipeline subjected to normal fault using a hybrid FEM-Ann approach

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 428-443页

作者： hedye JALALI Reza YEGAnEh KhAKSAR Danial MOhAMMADZADEh S. nader KARBALLAEEZADEh amir h.GAnDOMI Department of Civil Engineering Architecture and UrbanismSadjad University of TechnologyPO Box ***MashhadIran Department of Civil Engineering Faculty of EngineeringEqbal Lahoori Institute of Higher EducationPO Box ***MashhadIran Faculty of Civil Engineering Architectureand ArtScience and Research Branch of Islamic Azad UniversityPO Box ***TehranIran Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia University Research and Innovation Center(EKIK) Óbuda UniversityBudapest 1034Hungary

Fault movement during earthquakes is a geotechnical phenomenon threatening buried pipelines and with the potential to cause severe damage to critical ***,effective prediction of pipe displacement is crucial for preventive management *** study aims to develop a fast,hybrid model for predicting vertical displacement of pipe networks when they experience *** this study,the complex behavior of soil and a buried pipeline system subjected to a normal fault is analyzed by using an artificial neural network(Ann)to generate predictions the behavior of the soil when different parameters of it are *** this purpose,a finite element model is developed for a pipeline subjected to normal fault *** data bank used for training the Ann includes all the critical soil parameters(cohesion,internal friction angle,Young’s modulus,and faulting).Furthermore,a mathematical formula is presented,based on biases and weights of the Ann *** results show that the maximum error of the presented formula is 2.03%,which makes the proposed technique efficiently predict the vertical displacement of buried pipelines and hence,helps to optimize the upcoming pipeline projects.

关键词： buried pipelines normal Fault finite element method multilayer perceptron neural network formulation

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Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs

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Petroleum Science 2024年第2期21卷 951-961页

作者： amir Mohammad Zamani Ashkan Moslemi Kamran hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(nPs)to form nP-polymer suspension for enhanced oil recovery(EOR)in carbonate *** gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth ***,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay *** various scenarios,the effects of natural nPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,*** entire experiment was conducted at 25,50,and 75℃,*** to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio *** clay nPs,the combination of natural polymer and kaolinite results in increased viscosity at all *** wettability alteration was also observed in the case of natural polymer and illite *** in combination with natural polymer showed an ability in reducing ***,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

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Enhanced Chimp Optimization Algorithm Using Attack Defense Strategy and Golden Update Mechanism for Robust COVID-19 Medical Image Segmentation

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Journal of Bionic Engineering 2024年第4期21卷 2086-2109页

作者： amir hamza Morad Grimes Abdelkrim Boukabou Samira Dib non Testing Destructive Laboratory Faculty of TechnologyUniversity of Jijel18000JijelAlgeria Laboratory of Renewable Energy Faculty of TechnologyUniversity of Jijel18000JijelAlgeria

Medical image segmentation is a powerful and evolving technology in medical *** fact,it has been identified as a very effective tool to support and accompany doctors in their fight against the spread of the coronavirus(COVID-19).Various techniques have been utilized for COVID-19 image segmentation,including Multilevel Thresholding(MLT)-based meta-heuristics,which are considered crucial in addressing this ***,despite their importance,meta-heuristics have significant ***,the imbalance between exploration and exploitation,as well as premature convergence,can cause the optimization process to become stuck in local optima,resulting in unsatisfactory segmentation *** this paper,an enhanced War Strategy Chimp Optimization Algorithm(WSChOA)is proposed to address MLT *** strategies are incorporated into the traditional Chimp Optimization *** update mechanism that provides diversity in the ***,the attack and defense strategies are incorporated to improve the search space leading to avoiding local *** experimental results were conducted by comparing WSChoA with recent and well-known algorithms using various evaluation metrics such as Feature Similarity Index(FSIM),Structural Similarity Index(SSIM),Peak signal-to-noise Ratio(PSnR),Standard deviation(STD),Freidman Test(FT),and Wilcoxon Sign Rank Test(WSRT).The results obtained by WSChoA surpassed those of other optimization techniques in terms of robustness and accuracy,indicating that it is a powerful tool for image segmentation.

关键词： Image processing Segmentation Optimization Chimp Golden update mechanism Attack-defense strategy COVID-19

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Sedimentary facies analysis of a thin-bed-dominated turbidite succession in the Miocene Temburong Formation,Kampung Bebuloh,Labuan Island,Malaysia

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Journal of Palaeogeography 2024年第3期13卷 401-429页

作者： Farah Syafira Burhanuddin Meor hakif amir hassan Department of Geology Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia

Thin-bedded turbidites are important hydrocarbon-bearing reservoirs in many mature fields throughout the *** type of turbidite depositional setting strongly influences vertical and horizontal continuity of the ***,distinguishing between lobe and levee associated thin-bedded turbidites remains challenging due to their generally similar facies *** study aims to contribute some insights to this problem by conducting a detailed bed-scale facies analysis on the Early Miocene Temburong Formation exposed at Kampung Bebuloh,Labuan Island,Malaysia,which may uncover features that can help in differentiating between both depositional *** facies are recognized in the Temburong Formation,which are interpreted as low density turbidites(F1-F4),hybrid event beds(F5),and sustained turbidites(F6).Detailed facies and ichnology analysis reveal features which are consistent with a lobe fringe deposit rather than leveeassociated environment interpretation,including tabular bed geometries,presence of hybrid event beds,and the absence of thick-bedded channel-fill *** facies associations are identified and interpreted as representing sub-environments within an overall lobe depositional setting.A diverse trace fossil assemblage,comprising the nereites ichnofacies is consistent with a deep marine *** identification of the Paleodictyon and nereites sub-ichnofacies indicates a distal turbidite system setting,most likely lobe *** on the thick accumulation of FA2 and FA3 and no distinct observable vertical trend,the Early Miocene Temburong Formation in Labuan is interpreted as turbidites deposited at the fringes of lobe complexes rather than a single lobe *** works into the Temburong Formation in SW Labuan proposed a middle slope to proximal basin floor setting where the thin-bedded intervals were interpreted as potentially representing either levee deposits or the fringes of confined lobe ***

关键词： Facies analysis Trace fossils Depositional lobes hybrid event beds Lobe fringe Temburong formation Thin-bedded turbidite

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Machine learning based models for predicting compressive strength of geopolymer concrete

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1028-1049页

作者： Quang-huy LE Duy-hung nGUYEn Thanh SAnG-TO Samir KhATIR hoang LE-MInh amir h.GAnDOMI Thanh CUOnG-LE Center for Engineering Application and Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh 700000Vietnam Institute of Civil Engineering Ho Chi Minh City University of TransportHo Chi Minh 700000Vietnam Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia

Recently,great attention has been paid to geopolymer concrete due to its advantageous mechanical and environmentally friendly *** effort has been made in experimental studies to advance the understanding of geopolymer concrete,in which compressive strength is one of the most important *** facilitate engineering work on the material,an efficient predicting model is *** this study,three machine learning(ML)-based models,namely deep neural network(Dnn),K-nearest neighbors(Knn),and support vector machines(SVM),are developed for forecasting the compressive strength of the geopolymer concrete.A total of 375 experimental samples are collected from the literature to build a database for the development of the predicting models.A careful procedure for data preprocessing is implemented,by which outliers are examined and removed from the database and input variables are standardized before feeding to the fitting *** standard K-fold cross-validation approach is applied for evaluating the performance of the models so that overfitting status is well managed,thus the generalizability of the models is *** effectiveness of the models is assessed via statistical metrics including root mean squared error(RMSE),mean absolute error(MAE),correlation coefficient(R),and the recently proposed performance index(PI).The basic mean square error(MSE)is used as the loss function to be minimized during the model fitting *** three ML-based models are successfully developed for estimating the compressive strength,for which good correlations between the predicted and the true values are obtained for Dnn,Knn,and *** numerical results suggest that the Dnn model generally outperforms the other two models.

关键词： geopolymer concrete compressive strength prediction machine-learning based model deep neural network K-nearest neighbor support vector machines

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A rare complication of measles infection presented with subacute sclerosing panencephalitis: Report of two cases in India

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Asian Pacific Journal of Tropical Medicine 2024年第4期17卷 184-187页

作者： Razeen Fatima amir husain Iram Tabish Department of Medicine JN Medical CollegeAMUAligarhIndia

Rationale:Subacute sclerosing panencephalitis(SSPE)is a progressive neurological disorder caused by persistent measles virus *** predominantly affects children and *** symptoms usually develop 6-15 years after measles infection and ultimately leading to death in many *** concerns:Patient 1 presented with cognitive decline and myoclonus and the Patient 2 presented with diminution of vision with myoclonic ***:Based on the clinical features with a characteristic electroencephalogram pattern and the presence of a high titer of anti-measles IgG in serum and cerebrospinal fluid,these patients were diagnosed as ***:Antiepileptics were started for controlling myoclonus along with supportive ***:Both patients were discharged on antiepileptics and supportive ***:Whenever there are unusual clinical manifestations with unknown vaccination status,SSPE can be suspected and the cerebrospinal fluid should be examined for anti-measles *** case study also highlights the importance of universal coverage of measles *** reduce the incidence of measles and associated deaths,it is important to maintain a high level of immunization coverage for the measles vaccine and to strengthen all the integral components of the national immunization program.

关键词： Subacute sclerosing panencephalitis Measles Myoclonus Electroencephalogram Cerebrospinal fluid

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Prolonged asystole following adenosine. Was it necessary?

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Journal of Geriatric Cardiology 2024年第6期21卷 686-688页

作者： Yuval Avidan amir Aker Vsevolod Tabachnikov Department of Cardiology Lady Davis Carmel Medical CenterHaifaIsrael

A77-year-old woman presented with interchangeable episodes of both fast and slow heart *** history was notable for paroxysmal atrial fibrillation treated with eliquis and tambocor and atrial septal defect closure 35 years *** for mild tachycardia,vitals and physical examination were *** 12-lead electrocardiogram(Figure 1)showed narrow complex tachycardia at 106 beats/min without obvious P-waves.

关键词： tachycardia septal atrial

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