检索结果-南通市图书馆

Simulation of the deformable lateral boundaries in biaxial test using dEM

Particuology 2024年第5期88卷 161-175页

作者： ali Momeni Barry Clarke Yong Sheng ali Hassanpour WSP 3 Wellington PlaceLeedsLS1 4APUK Hull University HullHU6 7RXUK School of Civil Engineering University of LeedsLeedsLS2 9JTUK School of Computer Science University of HullHullHU6 7RXUK School of Chemical and Process Engineering University of LeedsLeedsLS2 9JTUK

Applying the discrete element method(dEM)in soil mechanics can provide abundant information at the particle-scale and facilitates illustration of the macro-mechanical behaviour of soils based on the inter-particle *** triaxial test is one of the most common laboratory methods to study the macro-mechanical behaviour of particulate materials such as ***,many problems in geotechnical design can be assumed and simplified as a plane strain *** a biaxial test can be conducted to reproduce the macro-mechanical behaviour of soil,where the sample is enclosed by two horizontal rigid platens and a vertical latex membrane,which is a deformable continuous element and allows the enclosed specimen to deform freely while maintaining confining stress during *** paper presents an algorithm to represent physical and mechanical characteristics of latex membrane in the 2d dEM simulation of biaxial test using the PFC^(2d) *** investigate the impact of the lateral boundary conditions on the micro-macro mechanical behaviours of soil samples,two sets of dEM biaxial tests are conducted,*** rigid and deformable lateral boundary *** dEM modeling results indicate that the lateral boundary conditions have a significant effect on the micro-scale fabric properties,thickness and inclination of the shear *** comparison between these two simulations also demonstrates that the lateral boundary conditions play a major role in the peak and post-peak stress-strain behaviours as well as the dilation and critical state behaviours of granular soils.

关键词： discrete element method Biaxial test deformable boundaries Shear band Critical state Fabric anisotropy Geometrical stability index

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Sensing the heavy water concentration in an H_(2)O-d_(2)O mixture by solid-solid phononic crystals

引用

Chinese Physics B 2024年第4期33卷 493-498页

作者： Mohammadreza Rahimi ali Bahrami Optoelectronic and Nanophotonics Research Laboratory(ONRL) Faculty of Electrical EngineeringSahand University of TechnologyTabrizIran

A new method based on phononic crystals is presented to detect the concentration of heavy water(d_(2)O)in an H_(2)O-d_(2)O *** have been obtained and analyzed in the concentration range of 0%-10%and 90%-100%d_(2)O.A proposed structure of tungsten scatterers in an aluminum host is *** order to detect the target material,a cavity region is considered as a sound wave resonator in which the target material with different concentrations of d_(2)O is *** changing the concentration of d_(2)O in the H_(2)O-d_(2)O mixture,the resonance frequency undergoes a frequency *** 1%change in d_(2)O concentration in the H_(2)O-d_(2)O mixture causes a frequency change of about 120 *** finite element method is used as the numerical method to calculate and analyze the natural frequencies and transmission spectra of the proposed *** performance evaluation index shows a high Q factor up to 1475758 and a high sensitivity up to 13075,which are acceptable values for sensing *** other figures of merit related to the detection performance also indicate high-quality performance of the designed sensor.

关键词： phononic crystals sensor H_(2)O-d_(2)O mixture cavity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A methodology for damage evaluation of underground tunnels subjected to static loading using numerical modeling

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1993-2005页

作者： Shahriyar Heidarzadeh ali Saeidi Rock Mechanics Engineer AtkinsRéalisMontrealQuebecCanada department of Applied Sciences Universitédu QuébecàChicoutimiChicoutimiQuebecCanada

We have proposed a methodology to assess the robustness of underground tunnels against potential *** involves developing vulnerability functions for various qualities of rock mass and static loading *** account for these variations,we utilized a Monte Carlo Simulation(MCS)technique coupled with the finite difference code FLAC^(3d),to conduct two thousand seven hundred numerical simulations of a horseshoe tunnel located within a rock mass with different geological strength index system(GSIs)and subjected to different states of static *** quantify the severity of damage within the rock mass,we selected one stress-based(brittle shear ratio(BSR))and one strain-based failure criterion(plastic damage index(PdI)).Based on these criteria,we then developed fragility ***,we used mathematical approximation techniques to produce vulnerability functions that relate the probabilities of various damage states to loading intensities for different quality classes of blocky rock *** results indicated that the fragility curves we obtained could accurately depict the evolution of the inner and outer shell damage around the ***,we have provided engineers with a tool that can predict levels of damages associated with different failure mechanisms based on variations in rock mass quality and in situ stress *** method is a numerically developed,multi-variate approach that can aid engineers in making informed decisions about the robustness of underground tunnels.

关键词： Fragility curves Underground tunnels Vulnerability functions Brittle damage FLAC3d Numerical modeling

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical-assisted MMP reduction on methane-oil systems:Implications for natural gas injection to enhanced oil recovery

引用

Petroleum 2024年第1期10卷 101-108页

作者： Mohamed Almobarak Matthew B.Myers Colin d.Wood Yongbing Liu ali Saeedi Quan Xie discipline of Petroleum Engineering WA School of Mines: Minerals Energy and Chemical Engineering Curtin University Commonwealth Scientific and Industrial Research Organization Curtin University Oil and Gas Innovation Centre Management State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation

Miscible natural gas injection is widely considered as a practical and efficient enhanced oil recovery technique. However, the main challenge in this process is the high minimum miscibility pressure（MMP）between natural gas and crude oil, which limits its application and recovery factor, especially in hightemperature reservoirs. Therefore, we present a novel investigation to quantify the effect of chemicalassisted MMP reduction on the oil recovery factor. Firstly, we measured the interfacial tension（IFT） of the methane-oil system in the presence of chemical or CO2to calculate the MMP reduction at a constant temperature（373K） using the vanishing interfacial tension（VIT） method. Afterwards, we performed three coreflooding experiments to quantify the effect of MMP reduction on the oil recovery factor under different injection *** interfacial tension measurements show that adding a small fraction（1.5 wt%） of the tested surfactant（SOLOTERRA ME-6） achieved 9% of MMP reduction, while adding 20 wt% of CO2to the methane yields 13% of MMP reduction. Then, the coreflooding results highlight the significance of achieving miscibility during gas injection, as the ultimate recovery factor increased from 65.5% under immiscible conditions to 77.2% using chemical-assisted methane, and to 79% using gas mixture after achieving near miscible condition. The results demonstrate the promising potential of the MMP reduction to significantly increase the oil recovery factor during gas injection. Furthermore, these results will likely expand the application envelop of the miscible gas injection, in addition to the environmental benefits of utilizing the produced gas by re-injection/recycling instead of flaring which contributes to reducing the greenhouse gas emissions.

关键词： Gas injection Enhanced oil recovery Miscibility Coreflooding

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

引用

Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： Gürel Cama ali Günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200˙Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-dEd),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of dEd technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing dEd processes Arc-dEd Wire arc additive manufacturing(WAAM) 3-d printing High deposition rate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

MoBShield:A Novel XML Approach for Securing Mobile Banking

引用

Computers, Materials & Continua 2024年第5期79卷 2123-2149页

作者： Saeed Seraj ali Safaa Sadiq OmprakashKaiwartya Mohammad Aljaidi Alexandros Konios Mohammed ali Mohammed Abazeed department of Computer Science Nottingham Trent UniversityClifton LaneNottinghamNG118NSUK department of Computer Science Faculty of Information TechnologyZarqa UniversityZarqa13110Jordan department of Computer Science King Khalid UniversityAbha61421Saudi Arabia

Mobile banking security has witnessed significant R&d attention from both financial institutions and *** is due to the growing number of mobile baking applications and their reachability and usefulness to ***,these applications are also attractive prey for cybercriminals,who use a variety of malware to steal personal banking *** literature in mobile banking security requiresmany permissions that are not necessary for the application’s intended security *** this context,this paper presents a novel efficient permission identification approach for securing mobile banking(MoBShield)to detect and prevent malware.A permission-based dataset is generated for mobile banking malware detection that consists large number of malicious adware apps and benign apps to use as training *** dataset is generated from 1650 malicious banking apps of the Canadian Institute of Cybersecurity,University of New Brunswick and benign apps from Google Play.A machine learning algorithm is used to determine whether amobile banking application ismalicious based on its permission ***,an eXplainable machine learning(XML)approach is developed to improve trust by explaining the reasoning behind the algorithm’s *** evaluation tests that the approach can effectively and practically identify mobile banking malware with high precision and reduced false ***,the adapted artificial neural networks(ANN),convolutional neural networks(CNN)and XML approaches achieve a higher accuracy of 99.7%and the adapted deep neural networks(dNN)approach achieves 99.6%accuracy in comparison with the state-of-the-art *** promising results position the proposed approach as a potential tool for real-world scenarios,offering a robustmeans of identifying and thwarting malware inmobile-based banking ***,MoBShield has the potential to significantly enhance the security and trustworthiness of

关键词： Security malware detection deep learning convolutional neural networks deep neural networks

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fuzzy difference Equations in diagnoses of Glaucoma from Retinal Images Using deep Learning

引用

Computer Modeling in Engineering & Sciences 2024年第4期139卷 801-816页

作者： d.dorathy Prema Kavitha L.Francis Raj Sandeep Kautish Abdulaziz S.Almazyad Karam M.Sallam ali Wagdy Mohamed department of Mathematics Voorhees CollegeVelloreTamil NaduIndia Chandigarh Group of Colleges JhanjeriMohaliPunjabIndia department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia Faculty of Science and Technology School of IT and SystemsUniversity of CanberraCanberraAustralia Operations Research department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied Science Research Center Applied Science Private UniversityAmman11937Jordan

The intuitive fuzzy set has found important application in decision-making and machine *** enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye detection using fuzzy difference equations in the domain where the retinal images *** image detections are categorized as normal eye recognition,suspected glaucomatous eye recognition,and glaucomatous eye *** degrees associated with weighted values are calculated to determine the level of concentration between the fuzzy partition and the retinal *** proposed model was used to diagnose glaucoma using retinal images and involved utilizing the Convolutional Neural Network(CNN)and deep learning to identify the fuzzy weighted regularization between *** methodology was used to clarify the input images and make them adequate for the process of glaucoma *** objective of this study was to propose a novel approach to the early diagnosis of glaucoma using the Fuzzy Expert System(FES)and Fuzzy differential equation(FdE).The intensities of the different regions in the images and their respective peak levels were *** the peak regions were identified,the recurrence relationships among those peaks were then *** partitioning was done due to varying degrees of similar and dissimilar concentrations in the *** and dissimilar concentration levels and spatial frequency generated a threshold image from the combined fuzzy matrix and *** distinguished between a normal and abnormal eye condition,thus detecting patients with glaucomatous eyes.

关键词： Convolutional Neural Network(CNN) glaucomatous eyes fuzzy difference equation intuitive fuzzy sets image segmentation retinal images

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Soliton solutions for nonlinear variable-order fractional Korteweg-de Vries(KdV)equation arising in shallow water waves

引用

Journal of Ocean Engineering and Science 2024年第1期9卷 50-58页

作者： Umair ali Hijaz ahm.d Hanaa Abu-Zinadah department of Applied Mathematics and Statistics Institute of Space TechnologyP.O.Box 2750Islamabad 44000Pakistan Near East University Operational Research Center in HealthcareNear East BoulevardPC:99138 Nicosia/Mersin 10Turkey Section of Mathematics International Telematic University UninettunoCorso Vittorio Emanuele II3900186 RomaItaly University of Jeddah College of ScienceDepartment of StatisticsJeddahSaudi Arabia

Nonlinear fractional differential equations provide suitable models to describe real-world phenomena and many fractional derivatives are varying with time and *** present study considers the advanced and broad spectrum of the nonlinear(NL)variable-order fractional differential equation(VO-FdE)in sense of VO Caputo fractional derivative(CFd)to describe the physical *** VO-FdE transforms into an ordinary differential equation(OdE)and then solving by the modified(G/G)-expansion *** ac-curacy,the space-time VO fractional Korteweg-de Vries(KdV)equation is solved by the proposed method and obtained some new types of periodic wave,singular,and Kink exact *** newly obtained solutions confirmed that the proposed method is well-ordered and capable implement to find a class of NL-VO *** VO non-integer performance of the solutions is studied broadly by using 2d and 3d graphical *** results revealed that the NL VO-FdEs are highly active,functional and convenient in explaining the problems in scientific physics.

关键词： Space-time VO fractional KdV equation modiﬁed(G′/G)-expansion method VO Caputo fractional derivative generalized Riccati equation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microstructural analysis of marl stabilized with municipal solid waste and nano-MgO

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3258-3269页

作者： ali Ohadian Navid Khayat Mehdi Mokhberi department of Civil Engineering Ahvaz BranchIslamic Azad UniversityAhvazIran department of Civil Engineering Estahban BranchIslamic Azad UniversityEstahbanIran

Municipal solid waste(MSW)is accumulating over elapsed time across the world,and it is observed in many projects associated with weak soils,such as ***,effective solutions to the environmental problem are *** techniques for stabilizing marl generally use substances such as lime and cement,which could exacerbate *** this,some new stabilizers,***-MgO,are *** are large quantities of marls and MSW in Shiraz City,*** present study aims to evaluate the feasibility of using nano-MgO as a green low-carbon binder to remove MSW from the environment and make construction projects more *** drained shear tests were conducted to evaluate the mechanical behaviors of the nano-MgO treated marl specimens at high normal *** marl specimens containing MSW percentages of 15%,25%,35%,and 45%and nano-MgO percentages of 0.25%,0.5%,0.75%,and 1%,were *** is found that the marl containing 15%and 25%MSW and 0.5%nano-MgO at 28-d curing can perform cation exchange and form new cementitious *** soils with merely MSW show good performance due to the removal of the kaolinite and the formation of ***,the soil with 25%MSW and 0.5%nano-MgO shows the same strength enhancement as the specimen with the optimal nano-MgO(0.75%)through the formation of dolomite,with a 20.59%increase in strain energy(SE).

关键词： Marl Shear strength Microstructure Nano-MgO Municipal solid waste(MSW)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Accurate 3d Thermal Network development for direct-drive Outer-rotor Hybrid-PM Flux-switching Generator

引用

Chinese Journal of Electrical Engineering 2024年第2期10卷 80-92页

作者： ali Zarghani Mohammad Farahzadi Aghil Ghaheri Karim Abbaszadeh Faculty of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran Faculty of Electrical Engineering University of Science and CultureTehran ***Iran department of Electrical Engineering K.N.Toosi University of TechnologyTehran ***Iran

Heat and thermal problems are major obstacles to achieving high power density in compact permanent magnet(PM)***,a comprehensive,accurate,and rapid temperature rise estimation method is required for novel electric machines to ensure safe and reliable operations.A unique three-dimensional(3d)lumped parameter thermal network(LPTN)is presented for accurate thermal modeling of a newly developed outer-rotor hybrid-PM flux switching generator(OR-HPMFSG)for direct-drive ***,the losses of the OR-HPMFSG are calculated using 3d finite element analysis(FEA).Subsequently,all machine components considering the thermal contact resistance,anisotropic thermal conductivity of materials,and various heat flow paths are comprehensively modeled based on the thermal *** the proposed 3-d LPTN,internal nodes are considered to predict the average temperature as well as the hot spots of all active and passive *** measurements are performed on a prototype OR-HPMFSG to validate the efficiency of the 3-d LPTN.A comparison of the results at various operating points between the developed 3-d LPTN,experimental test,and FEA indicates that the 3-d LPTN quickly approximates the hotspot and mean temperature of all components under both transient and steady states with high accuracy.

关键词： direct-drive wind turbine hybrid-PM flux switching generator lumped parameter thermal network temperature estimation 3d thermal modeling

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：