检索结果-南通市图书馆

Harnessing data using symbolic regression methods for discovering novel paradigms in physics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 1-11页

作者： Jianyang guo Wan-Jian Yin College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Shanghai Qi Zhi Institute Shanghai 200232China Light Industry Institute of Electrochemical Power Sources Soochow UniversitySuzhou 215006China

In recent years,machine-learning methods have profoundly impacted research in the interdisciplinary fields of ***,most machine-learning models lack interpretability,and physicists doubt the credibility of their conclusions because they cannot be combined with prior physical ***,this review focuses on symbolic regression,which is an interpretable machine-learning ***,the relevant concepts of machine learning are introduced in conjunction with ***,we provide an overview of symbolic regression ***,the recent directions for the application of symbolic regression methods in different subfields of physics are outlined,and an overview of the ways in which the applications of symbolic regression have evolved in the realm of physics is *** major aim of this review is to introduce the basic principles of symbolic regression and explain its applications in the field of physics.

关键词： machine learning genetic programming symbolic regression

Efficient electrocatalytic reduction of nitrate to ammonia at low concentration by copper-cobalt oxide nanowires with shell-core structure

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 5087-5094页

作者： Chenhao Xiao Yaxiao guo Jiayuan Sun Tao guo Xinyuan Jia Shinuo guo Guancheng Wu Yue Sun Zhaoyang Yao Yi Liu State Key Laboratory of Separation Membranes and Membrane Processes School of ChemistryTiangong UniversityTianjin 300387China Key Laboratory of Functional Polymer Materials College of ChemistryNankai UniversityTianjin 300071China School of Chemical and Environmental Engineering Wuhan Polytechnic UniversityWuhan 430023China

Electrocatalytic nitrate reduction to ammonia(NO3−RR)for removing nitrate from wastewater is a promising but challengeable technology that is increasingly ***,we developed an efficient CuO_(x)and CoCuO_(x)composed hybrid catalyst(CoCuO_(x)@CuO_(x)/copper foam(CF)),characteristic of distinctive shell-core nanowires grown on CF substrate with CuO_(x)core and CoCuO_(x)*** built-in electric field formed at the interface of the CoO/Cu_(2)O heterostructure promotes NO3−adsorption by modulating the charge distribution at the interface,which greatly improves the ammonia yield rate and Faradaic ***−0.2 V *** hydrogen electrode(RHE),CoCuO_(x)@CuO_(x)/CF achieves not only an excellent ammonia yield rate of up to 519.1μg·h^(−1)·cm^(−2)and Faradaic efficiency of 99.83%at 1 mM NO3−concentration,but also excellent mechanical *** study provides a novel pathway to design electrocatalyst for the removal of nitrate from dilute nitric acid solutions(≤2 mM).

关键词： CoCuO_(x)@CuO_(x)/copper foam(CF) shell-core nanowires heterostructure low concentration nitrate electroreduction to ammonia

Salp Swarm Incorporated Adaptive Dwarf Mongoose Optimizer with Lévy Flight and Gbest-Guided Strategy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第4期21卷 2110-2144页

作者： Gang Hu Yuxuan guo Guanglei Sheng Department of Applied Mathematics Xi’an University of TechnologyXi’an710054People’s Republic of China School of Computer Science and Engineering Xi’an University of TechnologyXi’an710048People’s Republic of China Department of Electronics and Information Engineering Bozhou UniversityBozhou236800People’s Republic of China

In response to the shortcomings of Dwarf Mongoose Optimization(DMO)algorithm,such as insufficient exploitation capability and slow convergence speed,this paper proposes a multi-strategy enhanced DMO,referred to as ***,we propose an improved solution search equation that utilizes the Gbest-guided strategy with different parameters to achieve a trade-off between exploration and exploitation(EE).Secondly,the Lévy flight is introduced to increase the diversity of population distribution and avoid the algorithm getting stuck in a local *** addition,in order to address the problem of low convergence efficiency of DMO,this study uses the strong nonlinear convergence factor Sigmaid function as the moving step size parameter of the mongoose during collective activities,and combines the strategy of the salp swarm leader with the mongoose for cooperative optimization,which enhances the search efficiency of agents and accelerating the convergence of the algorithm to the global optimal solution(Gbest).Subsequently,the superiority of GLSDMO is verified on CEC2017 and CEC2019,and the optimization effect of GLSDMO is analyzed in *** results show that GLSDMO is significantly superior to the compared algorithms in solution quality,robustness and global convergence rate on most test ***,the optimization performance of GLSDMO is verified on three classic engineering examples and one truss topology optimization *** simulation results show that GLSDMO achieves optimal costs on these real-world engineering problems.

关键词： Dwarf mongoose optimization algorithm Gbest-guided Lévy flight Adaptive parameter Salp swarm algorithm Engineering optimization Truss topological optimization

Research Progress on Bio‑inspired Flapping‑Wing Rotor Micro Aerial Vehicle Development

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第4期21卷 1621-1643页

作者： Yingjun Pan Shijun guo Xun Huang Centre for Aeronautics School of AerospaceTransport and ManufacturingCranfield UniversityBedford MK430ALUK

Flapping-wing rotor(FWR)is an innovative bio-inspired micro aerial vehicle capable of vertical take-off and *** unique design combines active flapping motion and passive wing rotation around a vertical central shaft to enhance aerodynamic *** research on FWR,though relatively new,has contributed to 6%of core journal publications in the micro aerial vehicle field over the past two *** paper presents the first comprehensive review of FWR,analysing the current state of the art,key advances,challenges,and future research *** review highlights FWR’s distinctive kinematics and aerodynamic superiority compared to traditional flapping wings,fixed wings,and rotary wings,discussing recent breakthroughs in efficient,passive wing pitching and asymmetric stroke amplitude for lift *** experiments and remote-controlled take-off and hovering tests of single and dual-motor FWR models have showcased their *** review compares FWR flight performance with well-developed insect-like flapping-wing micro aerial vehicles as the technology readiness level progresses from laboratory to outdoor flight testing,advancing from the initial flight of a 2.6 g prototype to the current free flight of a 60-gram *** review also presents ongoing research in bionic flexible wing structures,flight stability and control,and transitioning between hovering and cruise flight modes for an FWR,setting the stage for potential applications.

关键词： Flapping-wing rotor Micro aerial vehicle Bio-inspiration Flight

Multi-Objective Multi-Variable Large-Size Fan Aerodynamic Optimization by Using Multi-Model Ensemble Optimization Algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第3期33卷 914-930页

作者： XIONG Jin guo Penghua LI Jingyin School of Energy and Power Engineering Xi’an Jiaotong UniversityXi’an710049China

The constrained multi-objective multi-variable optimization of fans usually needs a great deal of computational fluid dynamics(CFD)calculations and is *** this study,a new multi-model ensemble optimization algorithm is proposed to tackle such an expensive optimization *** multi-variable and multi-objective optimization are conducted with a new flexible multi-objective infill *** addition,the search direction is determined by the multi-model ensemble assisted evolutionary algorithm and the feature extraction by the principal component analysis is used to reduce the dimension of optimization ***,the proposed algorithm and other two optimization algorithms which prevail in fan optimizations were compared by using test *** the same number of objective function evaluations,the proposed algorithm shows a fast convergency rate on finding the optimal objective function ***,this algorithm was used to optimize the rotor and stator blades of a large axial fan,with the efficiencies as the objectives at three flow rates,the high,the design and the low flow ***-two variables were included in the optimization *** results show that compared with the prototype fan,the total pressure efficiencies of the optimized fan at the high,the design and the low flow rate were increased by 3.35%,3.07%and 2.89%,respectively,after CFD simulations for 500 fan candidates with the constraint for the design *** optimization results validate the effectiveness and feasibility of the proposed algorithm.

关键词： multi-objective optimization surrogate-assisted evolutionary algorithm axial fan computational fluid dynamics aerodynamic optimization

Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 747-762页

作者： Hanxiao guo Peifeng GAO Xingzhe WANG Key Laboratory of Mechanics on Western Disaster and Environment of Ministry of Education Key Laboratory of Special Function Materials and Structure Design of Ministry of EducationCollege of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China

Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting *** respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic *** numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally ***,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake *** approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic *** then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic *** results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and *** proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets.

关键词： epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis

Robust Feedback Set Stabilization of Logic Networks with State-Dependent Uncertain Switching and Control Constraints

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年第2期37卷 629-646页

作者： DAI Chaoqun guo Yuqian GUI Weihua School of Automation Central South UniversityChangsha 410083China

This study investigates the robust feedback set stabilization of switched logic control networks(SLCNs)with state-dependent uncertain switching and control ***,based on the properties of the semi-tensor product of matrices and the vector representation of logic,an SLCN with state-dependent uncertain switching and control constraints is expressed in algebraic ***,an input transformation and a switching model are constructed to transfer the original SLCN into one with a free control input and arbitrary *** equivalence between the set stabilizability of the original SLCN and that of the resulting SLCN is *** on such equivalence,the authors propose a necessary and sufficient condition for robust feedback set ***,an example is presented to demonstrate the application of the results obtained.

关键词： Input transformation robust control invariant subset robust feedback set stabilizability semi-tensor product state-dependent constraints switched logic control network

A deformation criterion of pressurized non-circular cross-section cabin and its effects on cruise performance of BWB civil aircraft

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第6期37卷 78-88页

作者： Siyi guo Zhenli CHEN Xuanyu YAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aero Engine Academy of China Beijing 101304China

Blended-Wing-Body(BWB)aircraft is promoted as one of the most possible layouts to achieve more sustainable civil *** to the non-circular cross-section of the center-body,a bulge deformation forms over the upper surface of the body under the coupled loads of the internal pressurization of the cabin and the aerodynamic bending moments of the wing,which reduces the lift-to-drag ratio of BWB *** a limited deformation,the relationship between the aerodynamic performance and the structural weight needs to be *** this work,the effects of stiffness constraints on the center-body deformation,structural weight of the airframe and aerodynamic performance were investigated by using an analytical model of the Pultruded Rod Stitched Efficient Unitized Structure(PRSEUS)for the airframe and the computational fluid dynamics method,*** results show that as the stiffness constraint increases,the spacings between the rod stringers and the frame stiffeners decrease,and the structural weight increases inversely.A 5.2% reduction of the lift-to-drag ratio is encountered at cruise for a medium deformation design of 42.8 mm/m.A higher aerodynamic penalty is suffered when the stiffness constraint is further *** final deformation criterion is different when the weight vector of the aerodynamic performance and structural weight is different.

关键词： Blended-Wing-Body(BWB) Deformation PultrudedRod Stitched Effi-cient Unitized Structure(PRSEUS) Cabin structure Stiffness constraint

Forming process chain for manufacturing complex conical-section profiled rings:On a co-design method

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第6期37卷 485-503页

作者： Lei LIANG Chaojiang ZOU Lianggang guo State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Guizhou Aviation Technology Development Co.Ltd Guiyang 550081China

The final quality of complex conical-section rings depends on co-design of multiple processes in forming process *** this study,for a complex aeroengine casing ring with a large slope and a flange on its end,a co-design method of the forming process chain is put forward towards the objective of precision forming,which not only proposes a standard process route composed of multiple processes of upsetting,punching,rectangular ring rolling,loose tooling forging and profiled ring rolling,but also presents co-design methods of dies and blanks for all the *** profiled ring rolling,a design method of preformed blank that makes the blank and the target conical-section ring have the same axial volume distribution is *** the method,the axial metal redistribution during the process can be alleviated greatly thus improving the forming stability and precision of the *** on the geometric features of designed preformed blank,design methods of blanks and dies for loose tolling forging,rectangular ring rolling,punching and upsetting are proposed *** view of the key roles of loose tooling forging(manufacturing the preformed blank)and profiled ring rolling on the final quality of the conical ring parts,inherited FE simulations for these two processes are performed to verify the proposed design methods and determine appropriate design *** is demonstrated that the proposed design method has significant advantages in improving forming ***,a suggestive value 1.5 of the rolling ratio for profiled ring rolling(a key design parameter)is given based on comprehensive consideration of multiple indicators such as ring roundness,deformation uniformity and forming *** corresponding industrial experiments performed illustrate that a high forming precision of the conical-section aeroengine casing ring is achieved.

关键词： Complex conical-section ring Co-design of forming process chain Profiled ringrolling Preformed blank Loose tooling forging