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Improved genetic algorithm based on reinforcement learning for electric vehicle front-end structure optimization design

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Advances in Manufacturing 2024年第3期12卷 556-575页

作者： feng-yao Lyu Zhen-Fei Zhan Gui-Lin Zhou Ju Wang Jie Li Xin He Chongqing Jiaotong University Chongqing400074People’s Republic of China Changan Automobile Co.Ltd. Chongqing404100People’s Republic of China

The structural optimization of electric vehicles involves numerous design variables and constraints,making it a complex engineering optimization task over the past *** population-based evolutionary algorithms encounter issues such as converging to local optima and lacking population diversity when tackling such optimization ***,the solutions obtained for the optimization may be flawed or *** address these problems,an improved genetic algorithm(GA)based on reinforcement learning is proposed in this *** proposed method introduces a population delimitation method based on individual fitness *** population is divided into two parts:the excellent population and the ordinary population,and different selection and cross-mutation methods are applied to each part *** efficient crossover and mutation methods are then applied to the ordinary population to enhance the generation of excellent ***,the proposed approach replaces the traditional fixed crossover and mutation rates with a dynamic selection method based on reinforcement learning to enhance optimization efficiency.A markov decision process model is constructed based on GA environment in this *** population state determination method and reward method are designed for reinforcement learning in the GA environment,dynamically selecting the most appropriate genetic parameters based on the current state of the ***,the uncertainty in the manufacturing process is introduced into the optimization problem and the case study results demonstrate that the proposed reinforcement learning-based GA significantly outperforms other evolutionary algorithms when applied to solving the structural optimization of electric vehicles.

关键词： Structure optimization Genetic algorithm(GA) Q-learning

Helmholtz decomposition with a scalar Poisson equation in elastic anisotropic media

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Petroleum Science 2024年第3期21卷 1597-1610页

作者： Xin-Yu Fang Gang yao Qing-Qing Zheng Ping-Min Zhang Di Wu feng-Lin Niu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China Department of Mathematics College of ScienceChina University of Petroleum(Beijing)Beijing102249China College of Geophysics China University of Petroleum(Beijing)Beijing102249China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTX77005UA

P-and S-wave separation plays an important role in elastic reverse-time *** can reduce the artifacts caused by crosstalk between different modes and improve image *** addition,P-and Swave separation can also be used to better understand and distinguish wave types in complex *** present,the methods for separating wave modes in anisotropic media mainly include spatial nonstationary filtering,low-rank approximation,and vector Poisson *** of these methods require multiple Fourier transforms or the calculation of large matrices,which require high computational costs for problems with large *** this paper,an efficient method is proposed to separate the wave mode for anisotropic media by using a scalar anisotropic Poisson operator in the spatial *** 2D problems,the computational complexity required by this method is 1/2 of the methods based on solving a vector Poisson ***,compared with existing methods based on pseudoHelmholtz decomposition operators,this method can significantly reduce the computational *** examples also show that the P and S waves decomposed by this method not only have the correct amplitude and phase relative to the input wavefield but also can reduce the computational complexity significantly.

关键词： Anisotropic media Scalar anisotropic Poisson equation Improved elastic wavefield decomposition

Prediction of Bond Dissociation Energy for Organic Molecules Based on a Machine-Learning Approach

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Chinese Journal of Chemistry 2024年第17期42卷 1967-1974页

作者： Yidi Liu yao Li Qi Yang Jin-dong Yang Long Zhang Sanzhong Luo Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

Bond dissociation energy(BDE),which refers to the enthalpy change for the homolysis of a specific covalent bond,is one of the basic thermodynamic properties of *** is very important for understanding chemical reactivities,chemical properties and chemical ***,a machine learning-based comprehensive BDE prediction model was established based on the iBonD experimental BDE dataset and the calculated BDE dataset by *** et *** Structural and PhysicOChemical(D-SPOC)descriptors that reflected changes in molecules'structural and physicochemical features in the process of bond homolysis were designed as input features.

关键词： Bond dissociation energy Machine learning Molecular descriptors Prediction

Evaluation of the injection and plugging ability of a novel epoxy resin in cement cracks

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Petroleum Science 2024年第2期21卷 1211-1220页

作者： Guang-yao Leng Wei Yan Hai-Mu Ye Er-dong yao Ji-Bin Duan Zheng-Xian Xu Ke-Pei Li Jing-Ru Zhang Zhong Li State Key Laboratory of Petroleum Resource&Prospecting China University of Petroleum(Beijing)Beijing102249China CNPC Liaohe Oilfield Gas Storage Co.LTD Panjin124000LiaoningChina CNOOC Research Institute Co. Ltd.Beijing100028China

Sustained casing pressure(SCP)is a crucial issue in the oil and gas production *** resins,exhibiting exceptional compressive strength,ductility,and shear bonding strength,have the potential to form reliable *** injectivity and sealing capacity of the epoxy resin is crucial parameters for the success of shallow remediation *** study aimed to develop and assess a novel solid-free resin sealant as an alternative to Portland cement for mitigating fluid *** investigation evaluated the viscosity,compressive strength,and brittleness index of the epoxy resin sealant,as well as its tangential and normal shear strengths in conjunction with casing *** flow characteristics and sealing abilities of conventional cement and epoxy resin were comparatively analyzed in *** results showed that the application of a viscosity reducer facilitated control over the curing time of the epoxy resin,ranging from 1.5 to 6 h,and reduced the initial viscosity from 865.53 to 118.71 m Pa,*** mechanical properties of the epoxy resin initially increased with a rise in curing agent content before experiencing a minor *** epoxy resin containing 30%curing agent exhibited optimal mechanical *** a 14-day curing period,the epoxy resin's compressive strength reached81.37 MPa,2.12 times higher than that of cement,whereas the elastic modulus of cement was 2.99 times greater than that of the epoxy *** brittleness index of epoxy resin is only 3.42,demonstrating high flexibility and *** tangential and normal shear strengths of the epoxy resin exceeded those of cement by 3.17 and 2.82 times,*** a 0.5 mm-wide crack,the injection pressure of the epoxy resin remained below 0.075 MPa,indicating superior injection and flow ***,the injection pressure of cement surged dramatically to 2.61 MPa within 5 *** breakthrough pressure of0.5 PV epoxy resin reached 7.53 MPa,decreasing the crack's perme

关键词： Sustained casing pressure Epoxy resin sealant Curing agent Viscosity reducer Mechanical properties Crack sealing

Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020

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Journal of Mountain Science 2024年第9期21卷 3031-3046页

作者： GAO Bing LIU Enqin YANG Yang YANG Man yao Yang GUAN Lei feng Yiwen College of Geography and Planning Chengdu University of TechnologyChengdu 610059China Key Laboratory of Smart Earth Beijing 100029China Sichuan Provincial Soil and Water Conservation Ecological Environment Monitoring Station Chengdu 610041China College of Earth and Planetary Sciences Chengdu University of TechnologyChengdu 610059China

Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige ***,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain ***,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the ***,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the *** find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire ***,browning area expanded rapidly after *** temperatures are the primary driver of vegetation changes in the Zoige *** variations and human activities were responsible for 65.57%and 34.43%of vegetation greening,and 39.14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White *** to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020.

关键词： Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau

Internal electric field modulation by copper vacancy concentration of cuprous sulfide nanosheets for enhanced selective CO_(2) photoreduction

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Journal of Energy Chemistry 2024年第4期91卷 324-330页

作者： Xian Shi Weidong Dai Xiaoqian Li Yang Bai Qin Ren yao Lei Xing'an dong School of Chemistry and Environmental Engineering Sichuan University of Science&EngineeringZigong 643000SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation School of Oil&Natural Gas EngineeringSouthwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Key Laboratory of Photo-Electric Functional Materials College of Physics and Electronic EngineeringChongqing Normal UniversityChongqing 401331SichuanChina Research Center for Environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731SichuanChina

Although the internal electric field(IEF)of photocatalysts is acknowledged as a potent driving force for photocharge separation,modulating the IEF intensity to achieve enhanced photocatalytic performances remains a ***,cuprous sulfide nanosheets with different Cu vacancy concentration were employed to study IEF modulation and corresponding direct charge *** the samples,Cu_(1.8)S nanosheets possessed intensified IEF intensity compared with those of Cu_(2)S and Cu_(1.95)S nanosheets,suggesting that an enhanced IEF intensity could be achieved by introducing more Cu *** intensified IEF of Cu_(1.8)S nanosheets induced numerous photogenerated electrons to migrate to its surface,and the dissociative electrons were then captured by Cu vacancies,resulting in efficient charge separation *** addition,the Cu vacancies on Cu_(1.8)S nanosheets accumulated electrons as active sites to lower the energy barrier of rate-determining step of CO_(2)photoreduction,leading to the selective conversion of CO_(2)to ***,the manipulation of IEF intensity through Cu vacancy concentration regulation of cuprous sulfide photocatalysts for efficient charge separation has been discussed,providing a scientific strategy to rationally improve photocata lytic performances for solar energy conversion.

关键词： Internal electric field intensity Cuprous sulfide photocatalysts Cu vacancies Charge separation Selective CO_(2) photoreduction

Exceptional activity of amino-modified rGO-immobilized PdAu nanoclusters for visible light-promoted dehydrogenation of formic acid

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Chinese Chemical Letters 2024年第7期35卷 428-432页

作者： Yiyue Ding Qiuxiang Zhang Lei Zhang Qilu yao Gang feng Zhang-Hui Lu Key Laboratory of Energy Catalysis and Conversion of Nanchang College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022China School of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China

Formic acid(FA),which is obtainable through CO_(2)hydrogenation with green hydrogen or biomass conversion,has been used as a prospective liquid organic hydrogen carrier(LOHC)because of the abundant advantages of renewability,wide availability,stability,and high volumetric capacity(53 g H_(2)/L).The development of highly efficient catalytic systems to achieve enhanced catalytic activity is attractive but still ***,ultrafine and highly dispersed PdAu nanoclusters(NCs)anchored on amino-modified reduced graphene oxide(ArGO)were successfully synthesized via a facile impregnation-reduction method and applied as a catalyst toward formic acid dehydrogenation(FAD).Benefiting from the promoting effect of amino groups,the strain and ligand effect in the alloy,and the Mott–Schottky effect between PdAu NCs and ArGO,the resultant PdAu/ArGO affords an ultrahigh activity under visible light irradiation with an exceptional turnover frequency value of 10,699.5 h^(-1)at 298 K without any additives,more than 2.6times improvement than that under dark,which is the highest among all reported catalysts under the same *** study provides a green and convenient strategy for developing more efficient and sustainable FAD catalysts and promotes the effective utilization of FA as a prospective renewable LOHC.

关键词： Visible-light-enhanced Hydrogen production Formic acid Pd-Au Heterogeneous catalyst

Anti-OX40 Antibody Combined with HBc VLPs Delays Tumor Growth in a Mouse Colon Cancer Model

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Biomedical and Environmental Sciences 2024年第2期37卷 187-195页

作者： LIU Jia Jia SU Qiu dong YI yao SHEN Li Ping BI Sheng Li National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T cells,have attracted much attention for their excellent therapeutic *** this study,we aimed to evaluate the antitumor efficacy of combined anti-OX40 and hepatitis B core viruslike particles(HBc VLPs)therapy using a mouse colon cancer *** Humanized B-h OX40 mice were injected subcutaneously with MC38 colon tumor cells and treated with HBc VLPs+anti-h OX40 *** growth was *** cytometric analysis was performed to evaluate the populations of T cell subsets in the *** The combination of anti-OX40 with HBc VLPs resulted in a significant delay in tumor growth,suggesting that a potent antitumor immunity was induced by the combination *** studies revealed that HBc VLPs+anti-OX40 treatment induced a significant increase in effector T cells(Teffs)and a significant decrease in regulatory T cells(Tregs)in the tumor microenvironment(TME),which accounted for the synergistic antitumor effect of anti-OX40 in combination with HBc *** Combination therapy of anti-h OX40 and HBc VLPs provides synergistic antitumor activity in colon cancer-bearing mice,which may represent a potential design strategy for cancer immunotherapy.

关键词： Anti-OX40 antibody Hepatitis B core virus-like particles Tumor Combination therapy

Sulfhydryl-functionalized COF-based electrolyte strengthens chemical affinity toward polysulfides in quasi-solid-state Li-S batteries

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Carbon Energy 2024年第9期6卷 221-234页

作者： Linnan Bi Jie Xiao yaochen Song Tianrui Sun Mingkai Luo Yi Wang Peng dong Yingjie Zhang yao yao Jiaxuan Liao Sizhe Wang Shulei Chou Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhouChina National and Local Joint Engineering Research Center of Lithium-ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Battery Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunmingChina Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhouChina School of Materials and Energy University of Electronic Science and Technology of ChinaChengduChina School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science&TechnologyXi'anChina

For lithium-sulfur batteries(Li-S batteries),a high-content electrolyte typically can exacerbate the shuttle effect,while a lean electrolyte may lead to decreased Li-ion conductivity and reduced catalytic conversion efficiency,so achieving an appropriate electrolyte-to-sulfur ratio(E/S ratio)is essential for improving the battery cycling efficiency.A quasi-solid electrolyte(COF-SH@PVDF-HFP)with strong adsorption and high catalytic conversion was constructed for in situ covalent organic framework(COF)growth on highly polarized polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)***-SH@PVDF-HFP enables efficient Li-ion conductivity with low-content liquid electrolyte and effectively suppresses the shuttle *** results based on in situ Fourier-transform infrared,in situ Raman,UV–Vis,X-ray photoelectron,and density functional theory calculations confirmed the high catalytic conversion of COF-SH layer containing sulfhydryl and imine groups for the lithium *** plating/stripping tests based on Li/COF-SH@PVDF-HFP/Li show excellent lithium compatibility(5 mAh cm^(-2) for 1400 h).The assembled Li-S battery exhibits excellent rate(2 C 688.7 mAh g^(-1))and cycle performance(at 2 C of 568.8 mAh g^(-1) with a capacity retention of 77.3%after 800 cycles).This is the first report to improve the cycling stability of quasi-solid-state Li-S batteries by reducing both the E/S ratio and the designing strategy of sulfhydryl-functionalized COF for quasi-solid *** process opens up the possibility of the high performance of solid-state Li-S batteries.

关键词： lithium-sulfur batteries low electrolyte-to-sulfur ratio polysulfide shuttle PVDF-HFP/COF