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Data-Based Filters for Non-Gaussian Dynamic systems With Unknown Output Noise Covariance

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IEEE/CAA Journal of Automatica sinica 2024年第4期11卷 866-877页

作者： Elham Javanfar mehdi Rahmani the Department of Electrical Engineering Imam Khomeini International UniversityQazvin ***Iran

This paper proposes linear and nonlinear filters for a non-Gaussian dynamic system with an unknown nominal covariance of the output *** challenge of designing a suitable filter in the presence of an unknown covariance matrix is addressed by focusing on the output data set of the *** that data generated from a Gaussian distribution exhibit ellipsoidal scattering,we first propose the weighted sum of norms(sON)clustering method that prioritizes nearby points,reduces distant point influence,and lowers computational ***,by introducing the weighted maximum likelihood,we propose a semi-definite program(sDP)to detect outliers and reduce their impacts on each *** these weights paves the way to obtain an appropriate covariance of the output ***,two filtering approaches are presented:a cluster-based robust linear filter using the maximum a posterior(MAP)estimation and a clusterbased robust nonlinear filter assuming that output noise distribution stems from some Gaussian noise resources according to the ellipsoidal *** last,simulation results demonstrate the effectiveness of our proposed filtering approaches.

关键词： Data-based filter maximum likelihood estimation unknown covariance weighted maximum likelihood estimation weighted sum-of-norms clustering

Reinforcement Learning-Empowered Graph Convolutional Network Framework for Data Integrity Attack Detection in Cyber-Physical systems

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CsEE Journal of Power and Energy systems 2024年第2期10卷 797-806页

作者： Edeh Vincent mehdi Korki mehdi seyedmahmoudian Alex stojcevski saad Mekhilef school of science Computingand Engineering TechnologiesSwinburne University of TechnologyMelbourneAustralia

The massive integration of communication and information technology with the large-scale power grid has enhanced the efficiency, safety, and economical operation of cyber-physical systems. However, the open and diversified communication environment of the smart grid is exposed to cyber-attacks. Data integrity attacks that can bypass conventional security techniques have been considered critical threats to the operation of the grid. Current detection techniques cannot learn the dynamic and heterogeneous characteristics of the smart grid and are unable to deal with non-euclidean data types. To address the issue, we propose a novel Deep-Q-Network scheme empowered with a graph convolutional network (GCN) framework to detect data integrity attacks in cyber-physical systems. The simulation results show that the proposed framework is scalable and achieves higher detection accuracy, unlike other benchmark techniques.

关键词： Deep reinforcement learning graph convolutional network heterogeneous smart grid network

A novel mitigation measure for normal fault-induced deformations on pile-raft systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 15-33页

作者： Mohammadreza Jahanshahi Nowkandeh mehdi Ashtiani Faculty of Civil Engineering Babol Noshirvani University of TechnologyBabolIran

Evidence from recent earthquakes has shown destructive consequences of fault-induced permanent ground movement on *** observations have increased the demand for improvements in the design of structures that are dramatically vulnerable to surface fault *** this study a novel connection between the raft and the piles is proposed to mitigate the hazards associated with a normal fault on pile-raft systems by means of 3D finite element(FE)*** embarking on the parametric study,the strain-softening constitutive law used for numerical modeling of the sand has been validated against centrifuge test *** exact location of the fix-head and unconnected pile-raft systems relative to the outcropping fault rupture in the free-field is parametrically investigated,revealing different failure *** performance of the proposed connection for protecting the pile-raft system against normal fault-induced deformations is assessed by comparing the geotechnical and structural responses of both types of *** results indicate that the pocket connection can relatively reduce the cap rotation and horizontal and vertical displacements of the raft in most *** proposed connection decreases the bending moment response of the piles to their bending moment capacity,verging on a fault offset of 0.6 m at bedrock.

关键词： normal fault rupture failure mechanism pile-raft system pocket connection finite element modeling

On the occurrence of Neoplanorbulinella Matsumaru, 1976(Foraminifera) from the late Oligocene of Central Iran(Qom Formation):Palaeobiogeographic implications

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Journal of Palaeogeography 2024年第1期13卷 80-91页

作者： mehdi sarfi Mohsen Yazdi-Moghadam school of Earth sciences Damghan UniversityDamghan ***Iran National Iranian Oil Company Exploration Directorate Sheikh Bahaie SquareTehran ***Iran

The shallow marine carbonates of the upper Oligocene Qom Formation yielded several occurrences of the foraminiferan genus Neoplanorbulinella Matsumaru. Neoplanorbulinella saipanensis Matsumaru has so far been recorded from the late Eocene-early Miocene of Japan and late Oligocene of NE Italy whereas N. malatyaensis Gedik is only reported from the Oligocene from its type locality in the Malatya Basin, eastern Turkey. The new records reported here from the Qom Formation indicate that both species occur in the Dobaradar section, ca. 10 km south of the city of Qom in North-Central Iran. The palaeogeographic distribution of these two species therefore has to be extended as far as the palaeolongitude of current Central *** accompanying larger benthic foraminifers, including Miogypsinoides complanatus(schlumberger),M. formosensis Yabe and Hanzawa, spiroclypeus margaritatus(schlumberger), Operculina complanata(Defrance), and Risananeiza pustulosa Boukhary et al., indicate the upper Chattian sBZ 23 Zone. The coexistence of the N. saipanensis and N. malatyaensis points to suitable palaeobiogeographic conditions of Central Iran to host Western and Eastern Tethyan taxa.

关键词： Larger foraminifers Planorbulinids Biostratigraphy Qom Formation Central Iran

Coupling of RANs and BEM solvers for simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： saeed NAJAFI mehdi POURMOsTAFA LIU Peng-fei Iranian National Institute for Oceanography and Atmospheric science(INIOAs) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into *** main concern is to apply the wake effect of ship stern on the propeller *** this paper,a coupled BEM(Boundary Element Method)/RANs(Renolds-Averaged Navier−stokes)solver is used to simulate propeller behind the hull in the self-propulsion *** motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational *** unsteady boundary element method which is also known as panel method is chosen to estimate the propeller *** wakes are treated using a time marching wake alignment ***,a RANs code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANs *** on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time *** of the solver is carried out using the towing tank test report of a 50 m oceanography research *** factor and trust deduction coefficient are estimated ***,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANs BEM coupled method ship propeller self-propulsion wake sheet pattern

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

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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)

synergizing Wind,solar,and Biomass Power:Ranking Analysis of Off-Grid system for Different Weather Conditions of Iran

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Energy Engineering 2024年第6期121卷 1381-1401页

作者： Razieh Keshavarzi mehdi Jahangiri Energy and Environment Research Center Shahrekord BranchIslamic Azad UniversityShahrekordIran

Nowadays,the use of renewable energies,especially wind,solar,and biomass,is essential as an effective solution to address global environmental and economic ***,the current study examines the energy-economic-environmental analysis of off-grid electricity generation systems using solar panels,wind turbines,and biomass generators in various weather conditions in *** over 25 years were conducted using HOMER v2.81 software,aiming to determine the potential of each region and find the lowest cost of electricity production per *** the end,to identify the most suitable location,the Technique for Order Preference by similarity to Ideal solution(TOPsIs)method was employed to rank different stations based on simulation output parameters and some other influential *** the evaluation of various parameters,the stations in Yazd,Marand,and Dezful achieved the best results,while the stations in Ramsar,shahrekord,and Gonbad presented the least favorable *** Yazd,the wind turbine is an economic priority,and a 100 kW wind turbine is utilized in the optimal *** Yazd,where the simultaneous use of renewable energies is most prominent,the lowest pollutant production occurred with a quantity of 1174 kg/*** energy losses are highest in Jask station and lowest in Yazd.

关键词： Multi-criteria decision-making method residential scale biomass generators normalize weight

Evaluating innovation ecosystem resiliency using agent-based modeling and systems dynamics

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Journal of safety science and Resilience 2024年第2期5卷 204-221页

作者： soheila Abdi mehdi Yazdani Esmaeil Najafi Department of Industrial Engineering Science and Research BranchIslamic Azad UniversityTehranIran Department of Industrial Engineering Qazvin BranchIslamic Azad UniversityQazvinIran

Evaluating the resilience of the innovation ecosystem to maintain its performance,in the sense of resistance to disruption and recovery after it,has recently received more *** studies have been conducted to model different ecosystems and evaluate their ***,modeling the innovation ecosystem from a holistic perspective and performing a quantitative assessment of its resilience have received less *** paper models the innovation ecosystem holistically and evaluates its resilience index using a quantitative approach through five main *** the first step,a case study related to the innovation ecosystem of Iran's Ministry of Energy,called the Power Innovation Ecosystem,is modeled by combining system dynamics and agent-based *** validating the model in the second step,the disruption of the loss of experts is investigated in the third step,and all possible actions to recover each actor are *** the fourth step,the performance of the ecosystem is simulated before and after the disruption using the data gathered in the previous ***,resilience is calculated in two different ways in the fifth *** improvement solutions are also suggested when considering that the resilience index of the innovation ecosystem is at a medium *** research may assist policymakers in observing the resilience level of the innovation ecosystem based on the proposed *** applying strategic changes to this model,they can determine the effects of their policies and make the most appropriate decisions to increase the resilience of the innovation ecosystem.

关键词： Resilience index innovation ecosystem system dynamics Agent-based modeling

Powering the future: A comprehensive review on calcium-ion batteries

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Journal of Energy Chemistry 2024年第3期90卷 77-97,I0004页

作者： Ameneh Taghavi-Kahagh Hossein Roghani-Mamaqani mehdi salami-Kalajahi Faculty of Polymer Engineering Sahand University of TechnologyP.0.Box 51335-1996Tabriz Iran Institute of Polymeric Materials Sahand University of TechnologyP.0.Box 51335-1996Tabriz Iran

Due to concerns regarding the future availability,cost,and safety of lithium in Li-ion batteries(LIBs),researchers are exploring alternative chemistries such as Na-ion,Li-s,Li-air,and multivalent ion *** ion technologies,which utilize divalent or trivalent ions,like Mg^(2+),Ca^(2+),and Al^(3+),show promise in achieving greater energy densities than LIBs due to their ability to deposit uniformly on anodes and intercalate into *** magnesium-ion batteries(MIBs) have been the primary area of research for multivalent ion batteries,the cost-effectiveness and abundance of calcium have sparked a growing interest in calcium-ion batteries(CIBs) in recent *** to LIBs,CIBs have the potential to provide longer cycle life,enhanced safety,and increased energy ***,the development of CIBs comes with several challenges,such as finding suitable electrode and electrolyte materials that ensure the stability and safety of the *** primary hurdle in CIBs lies in the plating/stripping *** is a significant hindrance preventing the occurrence of plating/stripping in CIBs,which lies in the formation of a passive layer resulting from the decomposition of the *** objective of this article is to examine the advancements made in ***,it aims to comprehensively assess the mechanisms and materials employed in various battery components,as well as the obstacles encountered in *** includes recent advancements in electrode materials,electrolytes,cell configurations,and the challenges and opportunities for enhancing the performance and commercial viability of CIBs.

关键词： Ca-ion batteries Cathode Anode Electrolyte