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Towards implementation of alloy-specific thermo-fluid modelling for laser powder-bed fusion of Mg alloys

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Journal of Magnesium and Alloys 2024年第6期12卷 2327-2344页

作者： mohammad Hoseini-Athar Mikael Ersson Peter Hedström Department of Material Science and Engineering KTH Royal Institute of TechnologyStockholmSE-10044 Sweden

Multi-physics thermo-fluid modeling has been extensively used as an approach to understand melt pool dynamics and defect formation as well as optimizing the process-related parameters of laser powder-bed fusion(L-PBF).However,its capabilities for being implemented as a reliable tool for material design,where minor changes in material-related parameters must be accurately captured,is still in *** the present research,first,a thermo-fluid computational fluid dynamics(CFD)model is developed and validated against experimental *** the predicted material properties of the pure Mg and commercial ZK60 and WE43 Mg alloys,parametric studies are done attempting to elucidate how the difference in some of the material properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the melt pool *** is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation mass *** viscosity and wider solidification range can increase the non-uniformity of temperature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and formation of ***,the WE43 alloy showed the best behavior in terms of defect formation and evaporation mass loss,providing theoretical support to the extensive use of this alloy in *** summary,this study suggests an approach to investigate the effect of materials-related parameters on L-PBF melting and solidification,which can be extremely helpful for future design of new alloys suitable for L-PBF.

关键词： Mg alloys Laser powder-bed fusion(L-PBF) Melt pool dynamics Computational fluid dynamics Fluid flow

Advances in Manta Ray Foraging Optimization:A Comprehensive Survey

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Journal of Bionic Engineering 2024年第2期21卷 953-990页

作者： Farhad Soleimanian Gharehchopogh Shafi Ghafouri mohammad Namazi Bahman Arasteh Department of Computer Engineering Urmia BranchIslamic Azad UniversityUrmiaIran Department of Computer Engineering Tabriz BranchIslamic Azad UniversityTabrizIran Department of Computer Engineering Maybod BranchIslamic Azad UniversityMaybodIran Department of Software Engineering Faculty of Engineering and Natural ScienceIstinye UniversityIstanbulTurkey

This paper comprehensively analyzes the Manta Ray Foraging Optimization(MRFO)algorithm and its integration into diverse academic *** in 2020,the MRFO stands as a novel metaheuristic algorithm,drawing inspiration from manta rays’unique foraging behaviors—specifically cyclone,chain,and somersault *** biologically inspired strategies allow for effective solutions to intricate physical *** its potent exploitation and exploration capabilities,MRFO has emerged as a promising solution for complex optimization *** utility and benefits have found traction in numerous academic *** its inception in 2020,a plethora of MRFO-based research has been featured in esteemed international journals such as IEEE,Wiley,Elsevier,Springer,MDPI,Hindawi,and Taylor&Francis,as well as at international conference *** paper consolidates the available literature on MRFO applications,covering various adaptations like hybridized,improved,and other MRFO variants,alongside optimization *** trends indicate that 12%,31%,8%,and 49%of MRFO studies are distributed across these four categories respectively.

关键词： Manta ray foraging optimization Metaheuristic algorithms Hybridization Improved Optimization

Movement Trend Alterations in the Periaqueductal Gray(PAG)-Employed Ratbot Navigation Are Correlated with Stimulation Parameters

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Journal of Bionic Engineering 2024年第2期21卷 866-876页

作者： Sina Khajei Abed Khorasani mohammad Reza Afarinesh Vahid Sheibani Neuroscience Research Center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran Cognitive Neuroscience Research Center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran

In previous studies,Periaqueductal Gray(PAG)stimulation was used to stop ratbots from *** to the homology between the PAG and the intercollicular nucleus,which has been used for forward movement in birds,we investigated the possibility of PAG application to induce forward locomotion for the first *** a corridor maze,the traveled distances via PAG electrical stimulation were examined in nine Wistar male rats during three sessions.A custom-designed stimulator was developed to apply the *** results showed reductions in responses to stimulation over ***,the traveled distances had negative slopes during the consecutive trials(in 8 out of the 9 rats),and the slope mean was significantly different from *** was a strong correlation between the stimulation parameters(electric Charge per Phase(CPP)and the Number of Pulses(NP))and the observed *** negative Movement Slopes(MS)were highly correlated with the CPP and the NP,as the Pearson's linear correlation coefficients were−0.87 and−0.79,*** MS-CPP coefficients of determination(R-squared)were also between 0.76 and *** addition,the MS-NP coefficients of determination were between 0.63 and ***,it is concluded that the electrical stimulation parameters influence the behavioral outcomes ***,the PAG area may be considered a suitable candidate for forward locomotion control in the future if the area is harnessed effectively to prevent undesirable chaotic behaviors.

关键词： Periaqueductal Gray(PAG) Navigation Ratbot Animal-robot Forward locomotion Movement slope

Transient Stability Analysis of Grid-connected Converters in Wind Turbine Systems Based on Linear Lyapunov Function and Reverse-time Trajectory

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 782-790页

作者： mohammad Kazem Bakhshizadeh Sujay Ghosh Guangya Yang Łukasz Kocewiak Ørsted Wind Power A/S Nesa Allé12820Denmark Technical University of Denmark Anker Engelunds Vej 12800Denmark

As the proportion of converter-interfaced renewable energy resources in the power system is increasing,the strength of the power grid at the connection point of wind turbine generators(WTGs)is gradually *** research has shown that when connected with the weak grid,the stability of the traditional grid-following controlled converters will deteriorate,and they are prone to unstable phenomena such as *** to the limitations of linear analysis that cannot sufficiently capture the stability phenomena,transient stability must be *** far,standalone time-domain simulations or analytical Lyapunov stability criteria have been used to investigate transient ***,the time-domain simulations have proven to be computationally too heavy,while analytical methods are difficult to formulate for larger systems,require many modelling assumptions,and are often conservative in estimating the stability *** paper proposes and demonstrates an innovative approach to estimating the transient stability boundary via combining the linear Lyapunov function and the reverse-time trajectory *** proposed methodology eliminates the need of time-consuming simulations and the conservative nature of Lyapunov *** study brings out the clear distinction between the stability boundaries with different post-fault active current ramp rate *** the same time,it provides a new perspective on critical clearing time for wind turbine *** stability boundary is verified using time-domain simulation studies.

关键词： Lyapunov direct method non-autonomous system phase-locked loop(PLL) time trajectory reversal transient stability assessment wind turbine converter system

The anti-neoplastic effects of metformin modulate the acquired phenotype of fbroblast cells in the breast cancer-normal fbroblast co-culture system

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Oncology Research 2024年第3期32卷 477-487页

作者： SAMANEH MOSTAFAVI ZUHAIR mohammad HASSAN Department of Immunology Faculty of Medical SciencesTarbiat Modares UniversityTehranIran

Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy *** hallmarks of cancer fibroblast interactions,consisting of caveolin 1(Cav1)and mono-carboxylate ransporter 4(MCT4)(metabolic coupling markers),along with IL-6,TGFB,and lactate secretion,are considered robust biomarkers predicting recurrence and *** order to promote a novel phenotype in normal fibroblasts,we predicted that breast cancer cells could be able to cause loss of Cavl and increase of MCT4,as well as elevate IL 6 and TGF in nearby nomal *** created a co culture model using breast cancer(4T1)and normal fibroblast(NIH3T3)cell lines cultured under specific experimental conditions in order to directly test our ***,we show that long-term co-culture of breast cancer cells and normal fibroblasts promotes loss of Cavl and gain of MCT4 in adjacent fibroblasts and increase lactate *** results were validated using the monoculture of each group separately as a *** this system,we show that me tformin inhibits IL-6 and TGFB secretion and re expresses Cavl in both ***,MCT4 and lactate stayed high after treatment with *** conclusion,our work shows that co-culture with breast cancer cells may cause signifcant alterations in the phenotype and secretion of normal ***,however,may change this state and affect fibroblasts'acquired ***,mitochondrial inhibition by metformin after 8 days of treatment,signi ficantly hinders tumor growth in mouse model of breast cancer.

关键词： Caveolin 1 Lactic acid Metformin NIH 3T3 cells Neoplasms

Measuring Causal Effect with ARDL-BART: A Macroeconomic Application

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Applied Mathematics 2024年第4期15卷 292-312页

作者： Pegah Mahdavi mohammad ali Ehsani Daniel Felix Ahelegbey Mehrnaz mohammadpour Department of Economic and Administrative Sciences University of Mazandaran Babolsar Iran Department of Economics and Management Sciences University of Pavia Pavia Italy Department of Mathematical Sciences University of Mazandaran Babolsar Iran

Modeling dynamic systems with linear parametric models usually suffer limitation which affects forecasting performance and policy implications. This paper advances a non-parametric autoregressive distributed lag model that employs a Bayesian additive regression tree (BART). The performance of the BART model is compared with selection models like Lasso, Elastic Net, and Bayesian networks in simulation experiments with linear and non-linear data generating processes (DGP), and on US macroeconomic time series data. The results show that the BART model is quite competitive against the linear parametric methods when the DGP is linear, and outperforms the competing methods when the DGP is non-linear. The empirical results suggest that the BART estimators are generally more efficient than the traditional linear methods when modeling and forecasting macroeconomic time series.

关键词： BART Model Non Parametric Modeling Machine Learning Regression Trees Bayesian Network VAR

Wettability modification effects on relative permeability end-points:Comparative analysis of surfactant agents for enhanced oil recovery

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Petroleum Research 2024年第2期9卷 206-218页

作者： Erfan Hosseini Negar Hosseini mohammad Sarmadivaleh Exploration Directorate National Iranian Oil Company(NIOC)TehranIran Department of Petroleum Engineering Islamic Azad University(IAU)IlamIran WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWestern AustraliaAustralia

This research examines the impact of wettability alteration on the end points of relative permeability,a crucial property of fluids and porous media that influences the displacement processes of immiscible fluids through such *** estimation of the mobility ratio for oil recovery relies on these end points,which are influenced by connate water saturation and residual oil *** investigate this relationship,carbonate rock is generally subjected to wettability alteration using surfactant agents,and core flooding is employed to determine the relative permeability before and after the *** wettability of the rock is commonly assessed through contact angle *** surfactants,TritonX-100(Tx-100)and Cedar,were tested in reducing the wettability of the porous media for *** contact angle measurements revealed that Tx-100 was more effective for this purpose than ***,the relative permeability tests indicated that both surfactants decreased residual oil saturation,but Tx-100 also improved system *** contrast,Cedar reduced residual oil saturation but increased system pressure,possibly because of its high *** results also demonstrate that injecting Tx-100 leads to a 14%increase in ultimate oil recovery compared with water injection,while Cedar injection increased the recovery factor by 5%.This difference may be attributed to the incomplete coverage of the pore wall by Cedar or its weaker chemical structure than ***,in carbonate cores,neither non-ionic surfactant enhanced oil recovery.

关键词： Wettability alteration Relative permeability Core flooding Tx-100 Cedar Contact angle

Exploring Multi-Task Learning for Forecasting Energy-Cost Resource Allocation in IoT-Cloud Systems

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Computers, Materials & Continua 2024年第6期79卷 4603-4620页

作者： mohammad Aldossary Hatem A.Alharbi Nasir Ayub Department of Computer Engineering and Information College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Al-Dawasir11991Saudi Arabia Department of Computer Engineering College of Computer Science and EngineeringTaibah UniversityMadinah42353Saudi Arabia Department of Creative Technologies Air University IslamabadIslamabad44000Pakistan

Cloud computing has become increasingly popular due to its capacity to perform computations without relying on physical infrastructure,thereby revolutionizing computer ***,the rising energy consumption in cloud centers poses a significant challenge,especially with the escalating energy *** paper tackles this issue by introducing efficient solutions for data placement and node management,with a clear emphasis on the crucial role of the Internet of Things(IoT)throughout the research *** IoT assumes a pivotal role in this study by actively collecting real-time data from various sensors strategically positioned in and around data *** sensors continuously monitor vital parameters such as energy usage and temperature,thereby providing a comprehensive dataset for *** data generated by the IoT is seamlessly integrated into the Hybrid TCN-GRU-NBeat(NGT)model,enabling a dynamic and accurate representation of the current state of the data center *** the incorporation of the Seagull Optimization Algorithm(SOA),the NGT model optimizes storage migration strategies based on the latest information provided by IoT *** model is trained using 80%of the available dataset and subsequently tested on the remaining 20%.The results demonstrate the effectiveness of the proposed approach,with a Mean Squared Error(MSE)of 5.33%and a Mean Absolute Error(MAE)of 2.83%,accurately estimating power prices and leading to an average reduction of 23.88%in power ***,the integration of IoT data significantly enhances the accuracy of the NGT model,outperforming benchmark algorithms such as DenseNet,Support Vector Machine(SVM),Decision Trees,and *** NGT model achieves an impressive accuracy rate of 97.9%,surpassing the rates of 87%,83%,80%,and 79%,respectively,for the benchmark *** findings underscore the effectiveness of the proposed method in optimizing energy efficiency and enhancing the predictive

关键词： Cloud computing energy efficiency data center optimization internet of things(IoT) hybrid models

Synchrotron X-ray micro-computed tomography imaging of solid bridges between potash particles near contact points

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Particuology 2024年第9期92卷 24-29页

作者： Mojtaba Nabipoor Hassankiadeh mohammad Mehdi Heydari Carter Blocka Lifeng Zhang Department of Chemical and Biological Engineering University of SaskatchewanSKS7N 5A9SaskatoonCanada

Chemical fertilizers,such as potash,have a strong tendency to cake when exposed to *** this work,a novel synchrotron-based X-ray tomography 3D-imaging technique was for the first time employed to investigate the solid bridge formation from 2D and 3D *** processing and a theoretical model were presented to demonstrate recrystallization near contact points between potash particles during a conventional drying *** effect of initial moisture content on the water activity of surface surrounding the contact points was *** results showed that by increasing the moisture content of particles(3%–5%),the dissolution of sylvite increased and the solid bridge length between potash particles was enlarged from 28μm to 44μm due to supersaturation *** addition,the external porosity of potash particles at the end of drying process decreased from 25.3%to 19.5%for 3%and 5%moisture content,respectively.

关键词： Potash fertilizer Solid bridge Recrystallization Synchrotron X-ray micro-CT imaging Drying process