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Active learning of ternary alloy structures and energies

npj Computational Materials 2024年第1期10卷 2049-2059页

作者： Gaurav Deshmukh Noah J.Wichrowski Nikolaos Evangelou Pushkar G.Ghanekar Siddharth Deshpande Ioannis G.Kevrekidis Jeffrey Greeley Davidson School of Chemical Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Applied Mathematics and Statistics Johns Hopkins UniversityBaltimoreMD 21218USA Department of Chemical and Biomolecular Engineering Johns Hopkins UniversityBaltimoreMD 21218USA

Machine learning models with uncertainty quantification have recently emerged as attractive tools to accelerate the navigation of catalyst design spaces in a data-efficient ***,we combine active learning with a dropout graph convolutional network(dGCN)as a surrogate model to explore the complex materials space of high-entropy alloys(HEAs).We train the dGCN on the formation energies of disordered binary alloy structures in the Pd-Pt-Sn ternary alloy system and improve predictions on ternary structures by performing reduced optimization of the formation free energy,the target property that determines HEA stability,over ensembles of ternary structures constructed based on two coordinate systems:(a)a physics-informed ternary composition space,and(b)data-driven coordinates discovered by the Diffusion Maps manifold learning *** reduced optimization techniques improve predictions of the formation free energy in the ternary alloy space with a significantly reduced number of DFT calculations compared to a high-fidelity *** physicsbased scheme converges to the target property in a manner akin to a depth-first strategy,whereas the data-driven scheme appearsmore akin to a breadth-first *** sampling schemes,coupled with our acquisition function,successfully exploit a database of DFT-calculated binary alloy structures and energies,augmented with a relatively small number of ternary alloy calculations,to identify stable ternary HEA compositions and *** generalized framework can be extended to incorporate more complex bulk and surface structural motifs,and the results demonstrate that significant dimensionality reduction is possible in thermodynamic sampling problems when suitable active learning schemes are employed.

关键词： alloy ternary structures

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Machine learning for the identification of phase transitions in interacting agent-based systems: A Desai-Zwanzig example

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Physical Review E 2024年第1期110卷 014121-014121页

作者： Nikolaos Evangelou Dimitris G. Giovanis George A. Kevrekidis Grigorios A. Pavliotis Ioannis G. Kevrekidis Department of Chemical and Biomolecular Engineering Department of Applied Mathematics and Statistics Department of Civil and Systems Engineering Department of Mathematics

Deriving closed-form analytical expressions for reduced-order models, and judiciously choosing the closures leading to them, has long been the strategy of choice for studying phase- and noise-induced transitions for agent-based models (ABMs). In this paper, we propose a data-driven framework that pinpoints phase transitions for an ABM—the Desai-Zwanzig model—in its mean-field limit, using a smaller number of variables than traditional closed-form models. To this end, we use the manifold learning algorithm Diffusion Maps to identify a parsimonious set of data-driven latent variables, and we show that they are in one-to-one correspondence with the expected theoretical order parameter of the ABM. We then utilize a deep learning framework to obtain a conformal reparametrization of the data-driven coordinates that facilitates, in our example, the identification of a single parameter-dependent ordinary differential equation (ODE) in these coordinates. We identify this ODE through a residual neural network inspired by a numerical integration scheme (forward Euler). We then use the identified ODE—enabled through an odd symmetry transformation—to construct the bifurcation diagram exhibiting the phase transition.

关键词： Bifurcations Collective dynamics Dynamical systems High dimensional systems Multiple time scale dynamics Data mining Machine learning

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Some Results on Ricci-Yamabe Soliton and Its Cosmological Models

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IAENG International Journal of applied mathematics 2025年第4期55卷 979-983页

作者： Pandey, Pankaj Yadav, Santosh Kumar Sharma, Kamakshi Chaturvedi, Braj Bhushan Department of Mathematics School of Chemical Engineering and Physical Sciences Lovely Professional University Punjab Phagwara144411 India Department of Mathematics School of Computer Science & Artificial Intelligence SR University Telangana Warangal506371 India Department of Pure & Applied Mathematics Guru Ghasidas Vishwavidyalaya Chhattisgarh Bilaspur495009 India

This article aims to investigate the characteristics of Ricci-Yamabe Soliton (briefly: (RYS)n). We study the cosmological models on (RYS)4 under Lorentzian para Sasakian (LPS)4 spacetime. Parallel Ricci tensor, Poisson structure and gradient property also reveal on (RYS)n. Example of (RYS)4 constructed to verify the results. © (2025), (International Association of Engineers). All rights reserved.

关键词： Solitons

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Prediction of permeability from well logs using a new hybrid machine learning algorithm

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Petroleum 2023年第1期9卷 108-123页

作者： Morteza Matinkia Romina Hashami Mohammad Mehrad Mohammad Reza Hajsaeedi Arian Velayati Department of Petroleum Engineering Omidiyeh BranchIslamic Azad UniversityOmidiyehIran Department of Applied Mathematics Faculty of Mathematics and Computer SciencesAmirkabir University of TechnologyTehranIran Faculty of Mining Petroleum and Geophysics EngineeringShahrood University of TechnologyShahroodIran Department of Chemical and Materials Engineering University of AlbertaEdmontonCanada

Permeability is a measure of fluid transmissibility in the rock and is a crucial concept in the evaluation of formations and the production of hydrocarbon from the *** techniques such as intelligent methods have been introduced to estimate the permeability from other petrophysical *** efficiency and convergence issues associated with artificial neural networks have motivated researchers to use hybrid techniques for the optimization of the networks,where the artificial neural network is combined with heuristic *** research combines social ski-driver(SSD)algorithm with the multilayer perception(MLP)neural network and presents a new hybrid algorithm to predict the value of rock *** performance of this novel technique is compared with two previously used hybrid methods(genetic algorithm-MLP and particle swarm optimization-MLP)to examine the effectiveness of these hybrid methods in predicting the permeability of the *** results indicate that the hybrid models can predict rock permeability with excellent ***-SSD method yields the highest coefficient of determination(0.9928)among all other methods in predicting the permeability values of the test data set,followed by MLP-PSO and MLP-GA,***,the MLP-GA converged faster than the other two methods and is computationally less expensive.

关键词： Permeability Artificial neural network Multilayer perceptron Social ski driver algorithm

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The use of Carica papaya seeds as bio coagulant for laundry wastewater treatment

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Journal of engineering and applied Science 2024年第1期71卷 99页

作者： Vezar, Siti Alfinna Naulita Belinda, Zeriyatina Tri Rendana, Muhammad Agustina, Tuty Emilia Nasir, Subriyer Hanum, Laila Andarini, Desheila Undergraduate Student of Chemical Engineering Program Faculty of Engineering Universitas Sriwijaya Sumatra Selatan Indralaya30662 Indonesia Chemical Engineering Program Faculty of Engineering Universitas Sriwijaya Sumatra Selatan Indralaya30662 Indonesia Biology Department Faculty of Mathematics and Natural Sciences Universitas Sriwijaya Sumatra Selatan Indralaya30662 Indonesia Public Health Program Study Faculty of Public Health Universitas Sriwijaya Sumatra Selatan Indralaya30662 Indonesia

The study aims to analyze the effectiveness of wastewater treatment by using Carica papaya seeds as bio coagulants to diminish total suspended solids (TSS) and excess phosphate. This method has some advantages because it does not use chemical materials, is simple to apply, and is safe for the environment and human health. The wastewater samples were taken from an active laundry site in Palembang City, South Sumatra Province of Indonesia. The study found that the best dosage of coagulant was 3 g for the wastewater samples. The pH and BOD parameters showed slight changes after treatment, with pH 7.63–7.19 and 33–27 mg/L values, respectively. The TSS removal efficiency ranged from 9.3 to 15.6%, while the COD and phosphate removals were obtained from 11.7 to 39.3% and 56.3 to 68.4%, respectively. The treated TSS, COD, and phosphate concentrations have met the Indonesian domestic wastewater quality standard and environmental protection organization (EPO) guidelines. In addition, the statistical analysis and t-test showed significant differences (p © The Author(s) 2024.

关键词： Wastewater treatment

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Translation of a sphere towards a rigid plane in an Oldroyd-B fluid

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Physical Review Fluids 2024年第8期9卷 083303页

作者： Tachin Ruangkriengsin Rodolfo Brandão Bimalendu Mahapatra Evgeniy Boyko Howard A. Stone Program in Applied and Computational Mathematics Department of Mechanical and Aerospace Engineering Faculty of Mechanical Engineering

We analyze the low-Reynolds-number translation of a sphere towards or away from a rigid plane in an Oldroyd-B fluid under two scenarios: prescribing the sphere's translational velocity, and prescribing the force on the sphere. Leveraging the lubrication approximation and a perturbation expansion in powers of the Deborah number, we develop a comprehensive theoretical analysis that yields analytical approximations for velocity fields, pressures, and forces acting on the sphere. Our framework aids in understanding temporal microstructural changes as the particle-wall gap evolves over time. In particular, we show that alterations in the polymer conformation tensor in response to geometric changes induce additional forces on the sphere. For cases with prescribed velocity, we present a theoretical approach for calculating resistive forces at any order in the Deborah number and utilize a reciprocal theorem to obtain higher-order corrections based on velocity fields in the previous orders. When the sphere translates with a constant velocity, the fluid viscoelasticity decreases the resistive force at the first order. However, at the second-order correction, the direction of the sphere's movement determines whether viscoelasticity increases or decreases the resistive force. For cases with prescribed force, we show that understanding the influence of viscoelasticity on the sphere's translational velocity necessitates a more intricate analysis even at low Deborah numbers. Specifically, we introduce an ansatz for constant force scenarios, and we derive solution forms for general prescribed forces using the method of multiple scales. We find that when a sphere undergoes sedimentation due to its own weight, the fluid viscoelasticity results in a slower settling process, reducing the leading-order sedimentation rate.

关键词： Complex fluids Low Reynolds number flows Lubrication theory Polymer conformation changes Rheology

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Applications of variable thermal features for the bioconvective flow of Jeffrey nanofluids due to stretching surface with masssuction effects:Cattaneo-Christov model

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applied mathematics and Mechanics(English Edition) 2025年第2期46卷 391-402页

作者： S.U.KHAN M.GARAYEV ADNAN K.RAMESH M.EL MELIGY D.ABDUVALIEVA M.I.KHAN Department of Mathematics Namal UniversityMianwali 42250Pakistan Department of Mathematics College of ScienceKing Saud UniversityRiyadh 11421Saudi Arabia Department of Mathematics Mohi-ud-Din Islamic UniversityNerian Sharif 12080Pakistan Department of Pure and Applied Mathematics School of Mathematical SciencesSunway UniversityPetaling Jaya 47500Malaysia Department of Mathematics Graphic Era(Deemed to be University)DehradunUttarakhand 248002India Department of Mathematics School of Chemical Engineering and Physical SciencesLovely Professional UniversityPunjab 144411India Jadara University Research Center Jadara UniversityIrbid 21110Jordan Applied Science Research Center Applied Science Private UniversityAmman 11937Jordan Department of Mathematics and Information Technologies Tashkent State Pedagogical UniversityTashkent 100070Uzbekistan Department of Mechanics and Engineering Science Peking UniversityBeijing 100871China

The thermal nanofluids have garnered widespread attention for their use in multiple thermal systems,including heating processes,sustainable energy,and nuclear *** on nanofluids has revealed that the thermal efficiencies of such materials are adversely affected by various thermal *** purpose of the current work is to demonstrate the thermal analysis of Jeffrey nanofluids with the suspension of microorganisms in the presence of variable thermal *** variable effects of thermal conductivity,Brownian diffusivity,and motile density are *** investigated model also reveals the contributions of radiation phenomena and chemical reactions.A porous,saturated,moving surface with a suction phenomenon promotes *** modeling of the problem is based on the implementation of the Cattaneo-Christov *** convective thermal constraints are used to promote the heat transfer features.A simplified form of the governing model is treated with the assistance of a shooting *** physical effects of different parameters for the problem are *** current problem justifies its applications in heat transfer,coating processes,heat exchangers,cooling systems in microelectronics,solar systems,chemical processes,etc.

关键词： Jeffrey nanofluid bioconvection effect variable thermal consequence chemical reaction numerical simulation

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Lignin-based polyurethane composites enhanced with hydroxyapatite for controlled drug delivery and potential cellular scaffold applications

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Polymer Composites 2024年第16期45卷 15159-15172页

作者： Nugroho, Roshid Adi Saputra, Ozi Adi Pradita, Agung Lucky Fajar, Al Bukhori Nur Wibowo, Fajar Rakhman Department of Chemistry Faculty of Mathematics and Natural Sciences Universitas Sebelas Maret Central Java Surakarta Indonesia Sustainable Chemical Science and Technology Taiwan International Graduate Program Academia Sinica Taipei Taiwan Institute of Chemistry Academia Sinica Taipei Taiwan Department of Chemical Engineering Collage of Engineering National Taiwan University Taipei Taiwan

Polymer technology has rapidly advanced across diverse domains, particularly in biomedical applications. Among various polymers, polyurethane (PU) hold great potential in developing biomaterials such as biomedical scaffold and drug delivery. In this study, we have innovatively engineered eco-friendly polyurethane using lignin, a sustainable bio-polyol derived from oil palm empty fruit bunches. To enhance the physicochemical properties of the PU, we have incorporated hydroxyapatite (HA) into the composites. The inclusion of HA has led to notable improvements in crucial properties such as density, porosity, and water absorption, making these composites ideal candidates for tissue regeneration scaffolds. Furthermore, to assess their biomedical applicability in drug delivery and cell scaffolding, we have employed the quercetin drug model. The results revealed a sustained kinetic release behavior within the polyurethane/hydroxyapatite (PU/HA) composites, showcasing their potential for controlled drug delivery applications. Moreover, cytotoxicity assays conducted using neuro-2a cell models demonstrated the non-cytotoxic nature of both PU and PU/HA composites. This finding holds significant implications for biomedical applications, indicating that these composites offer biocompatible platforms for tissue engineering and regenerative medicine endeavors. The ability of these composites to support cell viability underscores their potential for a wide range of biomedical applications, including neural tissue engineering and drug delivery systems targeting brain diseases. These findings pave the way for the development of innovative and sustainable biomaterials with diverse biomedical applications. Highlights: An eco-friendly polyurethane has been engineered by harnessing liginin-derived oil palm empty fruit bunches. Incorporation of hydroxyapaptite enhance the physical properties of polyurethane. Controlled kinetic drug release is one of polyurethane/hydroxyapatite (PU/HA) com

关键词： Fruits

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Optimum classical beam-position sensing

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Physical Review applied 2024年第4期22卷 L041004页

作者： Wenhua He Christos N. Gagatsos Dalziel J. Wilson Saikat Guha Wyant College of Optical Sciences Department of Electrical and Computer Engineering Program in Applied Mathematics

Beam-displacement measurements are widely used in optical sensing and communications; however, their performance is affected by numerous intrinsic and extrinsic factors, including beam profile, propagation loss, and receiver architecture. Here we present a framework for designing a classically optimal beam-displacement transceiver, using quantum estimation theory. We consider the canonical task of estimating the position of a diffraction-limited laser beam after passing through an apertured volume characterized by Fresnel-number product DF. As a rule of thumb, higher-order Gaussian modes provide more information about beam displacement, but are more sensitive to loss. Applying quantum Fisher information, we design mode combinations that optimally leverage this trade-off, and show that a greater than tenfold improvement in precision is possible, relative to the fundamental mode, for a practically relevant DF=100. We also show that this improvement is realizable with a variety of practical receiver architectures. Our findings extend previous works on lossless transceivers, may have immediate impact on applications, such as atomic force microscopy and near-field optical communication, and pave the way towards globally optimal transceivers using nonclassical laser fields.

关键词： Classical optics Metrology Quantum Fisher information Quantum optics Quantum parameter estimation Devices Wireless communication networks Atomic force microscopy

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Wigner non-negative states that verify the Wigner entropy conjecture

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Physical Review A 2024年第1期110卷 012228-012228页

作者： Qipeng Qian Christos N. Gagatsos Program in Applied Mathematics The Department of Electrical and Computer Engineering The Wyant College of Optical Sciences The

We present further progress, in the form of analytical results, on the Wigner entropy conjecture set forth by Van Herstraeten and Cerf [Phys. Rev. A 104, 042211 (2021)] and Hertz et al. [J. Phys. A: Math. Theor. 50, 385301 (2017)]. Said conjecture asserts that the differential entropy defined for non-negative, yet physical, Wigner functions is minimized by pure Gaussian states while the minimum entropy is equal to 1+lnπ. We prove this conjecture for the qubits formed by Fock states |0〉 and |1〉 that correspond to non-negative Wigner functions. In particular, we derive an explicit form of the Wigner entropy for those states lying on the boundary of the set of Wigner non-negative qubits. We then consider general mixed states and derive a sufficient condition for the conjecture's validity. Lastly, we elaborate on the states which are in accordance with our condition.

关键词： Quantum foundations Quantum information theory

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