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

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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

Spreadability of powders for additive manufacturing:A critical review of metrics and characterisation methods

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Particuology 2024年第10期93卷 211-234页

作者： Fatemeh A.Talebi Zobaideh Haydari Hamid Salehi Mozhdeh Mehrabi Jabbar Gardy Mike Bradley Andrew e.Bayly ali Hassanpour School of Chemical and Process engineering University of LeedsLeedsLS29JTUK School of engineering University of GreenwichGreenwichME44TBUK Cormica Limited Listerhills Science ParkCampus RoadBradfordBD71HRUK

Powder bed fusion methods of additive manufacturing (AM) require consistent, reproducible, and uniform layers of powder for the reliable production of high-quality parts, where properties of powder are central to achieving this. Among these properties, powder flowability and spreadability play critical roles in determining the quality of these powder *** extensive research has been conducted on powder flow and spreading behaviour, and on their characterisation, there is little critical comparison and review of these terms in the context of AM. Such a review is necessary to further develop and enhance our comprehension of spreading dynamics and its relation to powder properties in AM *** review paper aims to build a coherent understanding of the correlation between powder characteristics and spreading in powder based additive manufacturing and its impact on manufactured parts. It highlights the current progress in comprehending spreading dynamics, the influence of powder characteristics, environmental conditions, spreading system, and the development of testing tools to assess powder spreadability. Furthermore, the paper critically discusses the challenge of finding appropriate quantitative metrics and recent advances in the use of standardised methods for evaluating powder spreadability.

关键词： Powder spreading Powder flowability Powder properties Quality of layer and final products

Communication-less Management Strategy for electric Vehicle Charging in Droop-controlled Islanded Microgrids

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Journal of Modern Power Systems and Clean energy 2024年第4期12卷 1227-1238页

作者： Abdullah Azhar Al-Obaidi Mohammed Zaki el-Sharafy Hany e.Z.Farag Saifullah Shafiq ali Al-Awami Independent electricity System Operator(IeSO) MississaugaCanada Department of electrical engineering and Computer Science York UniversityTorontoCanada University of Queensland StLucia QLD 4067Australia Department of electrical engineering King Fahd University of Petroleum&MineralsDhahranSaudi Arabia

Adopting high penetration levels of electric vehicles(eVs)necessitates the implementation of appropriate charging management systems to mitigate their negative impacts on pow-er distribution ***,most of the proposed ev charging management techniques rely on the availability of high-bandwidth communication *** techniques are far from realization due to①the lack of utility-grade communica-tion systems in many cases such as secondary(low-voltage)pow-er distribution systems to which eVs are connected,rural ar-eas,remote communities,and islands,and②existing fears and concerns about the data privacy of eV users and cyber-physical *** these cases,appropriate local control schemes are needed to ensure the adequate management of eV charging without violating the grid operation ***,this paper introduces a new communication-less management strategy for eV charging in droop-controlled islanded *** proposed strategy is autonomous,as it is based on the measurement of system frequency and local bus *** proposed strategy implements a social charging fairness policy during periods when the microgrid distributed genera-tors(DGs)are in short supply by allocating more system capaci-ty to the eVs with less charging in the ***,a novel communication-less eV load shedding scheme is incorpo-rated into the management strategy to provide relief to the mi-crogrid during events of severe undervoltage or underfrequency occurrences due to factors such as high loading or DG *** simulations demonstrate the superiority of the pro-posed strategy over the state-of-the-art controllers in modulat-ing the eV charging demand to counteract microgrid instability.

关键词： Charging battery management communication-less control droop control electric vehicle islanded microgrid

Boosted Lithium-Ion Transport Kinetics in n-Type Siloxene Anodes enabled by selective Nucleophilic Substitution of Phosphorus

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Nano-Micro Letters 2024年第10期16卷 618-637页

作者： se In Kim Woong-Ju Kim Jin Gu Kang Dong-Wan Kim School of Civil Environmental and Architectural EngineeringKorea University02841 SeoulSouth Korea Nanophotonics Research Center Korea Institute of Science and Technology02792 SeoulSouth Korea

Doped two-dimensional(2D)materials hold significant promise for advancing many technologies,such as microelectronics,optoelectronics,and energy ***,n-type 2D oxidized Si nanosheets,namely n-type siloxene(n-SX),are employed as Li-ion battery *** thermal evaporation of sodium hypophosphite at 275℃,P atoms are effectively incorporated into siloxene(SX)without compromising its 2D layered morphology and unique Kautsky-type crystal ***,selective nucleophilic substitution occurs,with only Si atoms being replaced by P atoms in the O_(3)≡Si-H *** resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types:(i)P atoms residing in Si sites and(ii)H *** doping concentrations are varied by controlling the amount of precursors or their mean free *** at 2000 mA g^(-1),the n-SX electrode with the optimized doping concentration(6.7×10^(19) atoms cm^(-3))delivers a capacity of 594 mAh g^(-1) with a 73%capacity retention after 500 *** improvements originate from the enhanced kinetics of charge transport processes,including electronic conduction,charge transfer,and solid-state *** approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage.

关键词： Li-ion battery Two-dimensional N-type siloxene Doping mechanism Kinetics

Ultrafast magneto-optical dynamics in nickel(111)single crystal studied by the integration of ultrafast reflectivity and polarimetry probes

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Chinese Physics B 2024年第3期33卷 65-69页

作者：匡皓余军潇陈洁 H.e.elsayed-ali 李润泽 peter M.Rentzepis School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China Center for Ultrafast Science and Technology Key Laboratory for Laser Plasmas (Ministry of Education)Collaborative Innovation Center of IFSA (CICIFSA)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Department of electrical and Computer engineering Old Dominion UniversityNorfolkVirginia 23529USA Department of electrical and Computer engineering Texas A&M UniversityCollege StationTexas 77843USA

With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single *** carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of *** the other hand,the observed spin dynamics indicate a longer time of about 120 *** further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.

关键词： ultrafast spin dynamics non-equilibrium dynamics multi-probe

Determination of uncertainties of geomechanical parameters of metamorphic rocks using petrographic analyses

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Journal of Rock Mechanics and Geotechnical engineering 2024年第2期16卷 345-364页

作者： Behzad Dastjerdy ali Saeidi Shahriyar Heidarzadeh Department of Applied Sciences University of Quebec at ChicoutimiSaguenayQCCanada SNC-Lavalin MontrealCanada

Geomechanical parameters of intact metamorphic rocks determined from laboratory testing remain highly uncertain because of the great intrinsic variability associated with the degrees of *** aim of this paper is to develop a proper methodology to analyze the uncertainties of geomechanical characteristics by focusing on three domains,*** treatment process,schistosity angle,and ***,the variabilities of the geomechanical laboratory data of Westwood Mine(Quebec,Canada)were examined statistically by applying different data treatment techniques,through which the most suitable outlier methods were selected for each parameter using multiple decision-making criteria and engineering *** indicated that some methods exhibited better performance in identifying the possible outliers,although several others were unsuccessful because of their limitation in large sample *** well-known boxplot method might not be the best outlier method for most geomechanical parameters because its calculated confidence range was not acceptable according to engineering ***,several approaches,including adjusted boxplot,2MADe,and 2SD,worked very well in the detection of true ***,the statistical tests indicate that the best-fitting probability distribution function for geomechanical intact parameters might not be the normal distribution,unlike what is assumed in most geomechanical ***,the negative effects of schistosity angle on the uniaxial compressive strength(UCS)variabilities were reduced by excluding the samples within a specific angle range where the UCS data present the highest ***,a petrographic analysis was conducted to assess the associated uncertainties such that a logical link was found between the dispersion and the variabilities of hard and soft minerals.

关键词： Intact rock parameters Natural variabilities Outlier detection methods Uncertainties Westwood mine Mineralogy

Unraveling fundamental properties of power system resilience curves using unsupervised machine learning

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energy and AI 2024年第2期16卷 227-240页

作者： Bo Li ali Mostafavi Urban Resilience.AI Lab Zachry Department of Civil and Environmental EngineeringTexas A&M University3136 TAMU College StationTX77843-3136USA

Power system is vital to modern societies,while it is susceptible to hazard ***,analyzing resilience characteristics of power system is *** standard model of infrastructure resilience,the resilience triangle,has been the primary way of characterizing and quantifying resilience in infrastructure systems for more than two ***,the theoretical model provides a one-size-fits-all framework for all infrastructure systems and specifies general characteristics of resilience curves(e.g.,residual performance and duration of recovery).Little empirical work has been done to delineate infrastructure resilience curve archetypes and their fundamental properties based on observational *** of the existing studies examine the characteristics of infrastructure resilience curves based on analytical models constructed upon simulated system *** is a dire dearth of empirical studies in the field,which hindered our ability to fully understand and predict resilience characteristics in infrastructure *** address this gap,this study examined more than two hundred power-grid resilience curves related to power outages in three major extreme weather events in the United *** the use of unsupervised machine learning,we examined different curve archetypes,as well as the fundamental properties of each resilience curve *** results show two primary archetypes for power grid resilience curves,triangular curves,and trapezoidal *** curves characterize resilience behavior based on three fundamental properties:*** functionality threshold,*** functionality recovery rate,and *** pivot *** archetypes explain resilience curves based on *** of sustained function loss and *** recovery *** longer the duration of sustained function loss,the slower the constant rate of *** findings of this study provide novel perspectives enabling better understanding and predicti

关键词： Power system Infrastructure resilience Unsupervised learning Time-series clustering Resilience curve

A Hybrid and Lightweight Device-to-server Authentication Technique for the Internet of Things

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Computers, Materials & Continua 2024年第3期78卷 3805-3823页

作者： Shaha Al-Otaibi Rahim Khan Hashim ali Aftab Ahmed Khan Amir Saeed Jehad ali Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer Science Abdul Wali Khan University MardanMardan23200Pakistan Department of Computer Science and IT UET PeshawarJalozai Campus PeshawarPeshawar24240Pakistan Department of AI Convergence Network Ajou UniversitySuwon16499South Korea

The Internet of Things(IoT)is a smart networking infrastructure of physical devices,i.e.,things,that are embedded with sensors,actuators,software,and other technologies,to connect and share data with the respective server *** IoTs are cornerstones in different application domains,the device’s authenticity,i.e.,of server(s)and ordinary devices,is the most crucial issue and must be resolved on a priority ***,various field-proven methodologies were presented to streamline the verification process of the communicating devices;however,location-aware authentication has not been reported as per our knowledge,which is a crucial metric,especially in scenarios where devices are *** paper presents a lightweight and location-aware device-to-server authentication technique where the device’s membership with the nearest server is subjected to its location information along with other ***,Media Access Control(MAC)address and Advance encryption Scheme(AeS)along with a secret shared key,i.e.,λ_(i) of 128 bits,have been utilized by Trusted Authority(TA)to generate MaskIDs,which are used instead of the original ID,for every device,i.e.,server and member,and are shared in the offline ***,TA shares a list of authentic devices,i.e.,server S_(j) and members C_(i),with every device in the IoT for the onward verification process,which is required to be executed before the initialization of the actual communication ***,every device should be located such that it lies within the coverage area of a server,and this location information is used in the authentication process.A thorough analytical analysis was carried out to check the susceptibility of the proposed and existing authentication approaches against well-known intruder attacks,i.e.,man-in-the-middle,masquerading,device,and server impersonations,etc.,especially in the IoT ***,proposed authentication and existing state-of-the-art approaches have been s

关键词： Internet of things authenticity security location communication

Demystifying polyphosphate-accumulating organisms relevant to wastewater treatment: A review of their phylogeny, metabolism, and detection

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environmental Science and ecotechnology 2024年第5期21卷 1-16页

作者： Lucia Ruiz-Haddad Muhammad ali Mario Pronk Mark C.Mvan Loosdrecht Pascal e.Saikaly environmental Science and engineering Program Biological and Environmental Science and Engineering(BESE)DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal23955-6900Saudi Arabia Water Desalination and Reuse Center Biological and Environmental Science and Engineering(BESE)DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal23955-6900Saudi Arabia Department of Civil Structural&Environmental EngineeringTrinity College DublinThe University of DublinDublin2Ireland Department of Biotechnology Delft University of TechnologyDelft2629 HZthe Netherlands

Currently,the most cost-effective and efficient method for phosphorus(P)removal from wastewater is enhanced biological P removal(ePBR)via polyphosphate-accumulating organisms(PAOs).This study integrates a literature review with genomic analysis to uncover the phylogenetic and metabolic diversity of the relevant PAOs for wastewater *** findings highlight significant differences in the metabolic capabilities of PAOs relevant to wastewater ***,Candidatus Dechloromonas and Candidatus Accumulibacter can synthesize polyhydroxyalkanoates,possess specific enzymes for ATP production from polyphosphate,and have electrochemical transporters for acetate and *** contrast,Tetrasphaera,Candidatus Phosphoribacter,Knoellia,and Phycicoccus possess PolyP-glucokinase and electrochemical transporters for sugars/amino ***,this review explores various detection methods for polyphosphate and PAOs in activated sludge wastewater treatment ***,FISH-Raman spectroscopy emerges as one of the most advanced detection ***,this review provides critical insights into PAO research,underscoring the need for enhanced strategies in biological phosphorus removal.

关键词： Polyphosphate-accumulating organisms(PAOs) enhanced biological phosphorus removal (eBPR)Tetrasphaera Ca.accumulibacter Ca.phosphoribacter Knoellia Phycicoccus