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Enhancing cut selection through reinforcement learning

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Science china Mathematics 2024年第6期67卷 1377-1394页

作者： Shengchao Wang Liang Chen Lingfeng Niu Yu-Hong Dai Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China research center on Fictitious economy and Data Science Chinese Academy of SciencesBeijing100190China

With the rapid development of artificial intelligence in recent years,applying various learning techniques to solve mixed-integer linear programming(MILP)problems has emerged as a burgeoning research *** from constructing end-to-end models directly,integrating learning approaches with some modules in the traditional methods for solving MILPs is also a promising *** cutting plane method is one of the fundamental algorithms used in modern MILP solvers,and the selection of appropriate cuts from the candidate cuts subset is crucial for enhancing *** to the reliance on expert knowledge and problem-specific heuristics,classical cut selection methods are not always transferable and often limit the scalability and generalizability of the cutting plane *** provide a more efficient and generalizable strategy,we propose a reinforcement learning(RL)framework to enhance cut selection in the solving process of ***,we design feature vectors to incorporate the inherent properties of MILP and computational information from the solver and represent MILP instances as bipartite ***,we choose the weighted metrics to approximate the proximity of feasible solutions to the convex hull and utilize the learning method to determine the weights assigned to each ***,a graph convolutional neural network is adopted with a self-attention mechanism to predict the value of weighting ***,we transform the cut selection process into a Markov decision process and utilize RL method to train the *** experiments are conducted based on a leading open-source MILP solver *** on both general and specific datasets validate the effectiveness and efficiency of our proposed approach.

关键词： reinforcement learning mixed-integer linear programming cutting plane method cut selection

Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative

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Petroleum Science 2024年第2期21卷 1429-1443页

作者： Bao-Jun Tang Chang-Jing Ji Yu-Xian Zheng Kang-Ning Liu Yi-Fei Ma Jun-Yu Chen center for Energy and Environmental Policy research Beijing Institute of TechnologyBeijing100081China School of Management and Economics Beijing Institute of TechnologyBeijing100081China Collaborative Innovation center of Electric Vehicles in Beijing BeijingChina Sustainable Development research Institute for economy and Society of Beijing BeijingChina Institute of Carbon Neutrality ShanghaiTech UniversityShanghai201210China

With the implementation of the Belt and Road Initiative, china is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for china's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.

关键词： Belt and Road Initiative Oil and Gas Investment Risk assessment

Recent advances and perspectives of zinc metal-free anodes for zinc ion batteries

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 33-47页

作者： Jiabing Miao Yingxiao Du Ruotong Li Zekun Zhang Ningning Zhao Lei Dai Ling Wang Zhangxing He Science and Technology Innovation center of Circular economy Ha’erwusu Open-Pit Coal MineChina Shenhua Energy Co.Ltd.Ordos 010300China research center of Comprehensive Utilization of Coal Associated Resources National Energy GroupOrdos 010300China School of Chemical Engineering North China University of Science and TechnologyTangshan 063009China

Zinc-ion batteries(ZIBs) are recognized as potential energy storage devices due to their advantages of low cost, high energy density, and environmental friendliness. However, zinc anodes are subject to unavoidable zinc dendrites, passivation, corrosion, and hydrogen evolution reactions during the charging and discharging of batteries, becoming obstacles to the practical application of ZIBs. Appropriate zinc metal-free anodes provide a higher working potential than metallic zinc anodes, effectively solving the problems of zinc dendrites, hydrogen evolution, and side reactions during the operation of metallic zinc anodes. The improvement in the safety and cycle life of batteries creates conditions for further commercialization of ZIBs. Therefore, this work systematically introduces the research progress of zinc metal-free anodes in “rocking chair” ZIBs. Zinc metal-free anodes are mainly discussed in four categories: transition metal oxides,transition metal sulfides, MXene(two dimensional transition metal carbide) composites, and organic compounds, with discussions on their properties and zinc storage mechanisms. Finally, the outlook for the development of zinc metal-free anodes is proposed. This paper is expected to provide a reference for the further promotion of commercial rechargeable ZIBs.

关键词： zinc ion batteries anode zinc metal-free anode recent advances perspectives

Impact and prediction of pollutant on mangrove and carbon stocks:A machine learning study based on urban remote sensing data

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Geoscience Frontiers 2024年第3期15卷 401-418页

作者： Mengjie Xu Chuanwang Sun Yanhong Zhan Ye Liu Institute of Artificial Intelligence Xiamen UniversityXiamen 361005FujianChina china center for Energy Economics research School of EconomicsXiamen UniversityXiamen 361005FujianChina Laboratory of Smart Energy and Green economy Institute of Artificial IntelligenceXiamen UniversityXiamen 361005FujianChina Department of Public Finance School of EconomicsXiamen UniversityXiamen 361005China

Mangrove ecosystems have important ecological and economic values,especially their ability to store ***,in recent years,human disturbance has accelerated mangrove *** them,the emission of pollutants cannot be *** is of great significance for carbon emission reduction and ecological protection to study the impacts of different pollutants on mangroves and their carbon *** on the remote sensing data of coastal areas south of the Yangtze River in china's Mainland,this paper builds the ensemble learning model Random Forest(RF)and Gradient Boosting Regression(GBR)to empirically analyse the relationship between industrial wastewater,industrial sulfur dioxide(SO2),PM2.5 and mangrove *** results show that the pollutant concentration of meteorological normalisation is more *** importance of pollutants presents regional *** area of mangroves in different cities and the corresponding total carbon stocks show different trends with the increase or decrease of pollutants,and there is a dynamic balance between urban pollutant discharge and mangrove growth in some *** research in this paper provides an analysis and explanation from the perspective of machine learning to explore the relationship between mangroves and pollutants and at the same time,provides scientific suggestions for the formulation of future pollutant emission policies in different cities.

关键词： Mangrove forests Pollutants Machine learning model Carbon stocks Regional heterogeneity

Dietary polyphenols reduced the allergenicity ofβ-lactoglobulin via non-covalent interactions:a study on the structure-allergenicity relationship

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Food Science and Human Wellness 2024年第5期13卷 2617-2628页

作者： Chi Zhang Qiaozhi Zhang Huatao Li Zhouzhou Cheng Shiyu Fan Hujun Xie Zhongshan Gao Yan Zhang Linglin Fu School of Food Science and Biotechnology Zhejiang Gongshang UniversityHangzhou 310018China Allergy research center Zhejiang UniversityHangzhou 310018China Hebei Food Inspection and research Institute Hebei Food Safety Key LaboratoryKey Laboratory of Special Food Supervision Technology for State Market RegulationHebei Engineering Research Center for Special Food Safety and HealthShijiazhuang 050227China

Studies showed that complexation of polyphenols with milk allergens reduced their immunogenic ***,the relationship between structures of polyphenols and their hypoallergenic effects on milk allergens in association with physiological and conformational changes of the complexes remain *** this study,polyphenols from eight botanical sources were extracted to prepare non-covalent complexes withβ-lactoglobulin(β-LG),a major allergen in *** dominant phenolic compounds bound toβ-LG with a diminished allergenicity were identified to investigate their respective role on the structural and allergenic properties ofβ-*** from Vaccinium fruits and black soybeans were found to have great inhibitory effects on the IgE-and IgG-binding abilities ofβ-*** the fourteen structure-related phenolic compounds,flavonoids and tannins with larger MWs and multi-hydroxyl substituents,notably rutin,EGCG,and ellagitannins were more potent to elicit changes on the conformational structures ofβ-LG to decrease the allergenicity of complexedβ-*** analysis further demonstrated that a destabilized secondary structure and protein depolymerization caused by polyphenol-binding were closely related to the allergenicity property of formed *** study provides insights into the understanding of structure-allergenicity relationship ofβ-LG-polyphenol interactions and would benefit the development of polyphenol-fortified matrices with hypoallergenic potential.

关键词： Cow’s milk allergy β-Lactoglobulin Protein-polyphenol interaction Allergenicity Conformational structure

Data as a Factor of Production Promoting the Deep Integration of the Digital economy and the Real economy:Theoretical Logic and Analysis Framework

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Frontiers of Economics in china-Selected Publications from Chinese Universities 2024年第2期19卷 129-153页

作者： OUYANG Rihui china center for Internet economy research Central University of Finance and EconomicsBeijing 100081China

Data is the primary factor of production in the digital economy,playing a role in promoting the deep integration of the digital economy and the real economy and smoothing the national economic *** entering the circulation system of the real economy,data is rapidly integrated into production,circulation,consumption,distribution,and other *** optimizes resource allocation,unblocks circulation channels,promotes accurate matching of supply and demand,stimulates emerging demand,and forms a virtuous circle of digital technology application,traditional physical enterprise transformation,and technological *** development is an important feature of the digital *** promotes the integration of factors of production,products,enterprises,industries,and markets,which fosters a circular system with deep integration of the digital economy and the real *** promote the deep integration of the digital economy and the real economy,the government and business entities should take measures to improve the circular efficiency of the digital economy and the real *** measures include attaching importance to the role of data-driven development,improving data capacity,data development,and utilization in enterprises,exploring diverse circulation models of enterprise data,and creating typical application scenarios and industrial data spaces.

关键词： data data as a factor of production(data factor) digital economy real economy integrated development

Simulation of gas-solid flow characteristics of the circulating fluidized bed boiler under pure-oxygen combustion conditions

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Chinese Journal of Chemical Engineering 2024年第6期70卷 9-19页

作者： Kaixuan Gao Xiwei Ke Bingjun Du Zhenchuan Wang Yan Jin Zhong Huang Yanhong Li Xuemin Liu Key Laboratory of Special Equipment Safety and Energy-Saving for State market Regulation China Special Equipment Inspection&Research InstituteBeijing 100029China Department of Energy and Power Engineering Tsinghua UniversityBeijing 100084China School of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China

Under the pressure of carbon neutrality,many carbon capture,utilization and storage technologies have witnessed rapid development in the recent years,including oxy-fuel combustion(OFC)***,the conventional OFC technology usually depends on the flue gas recirculation system,which faces significant investment,high energy consumption,and potential low-temperature corrosion *** these deficiencies,the direct utilization of pure oxygen to achieve particle fluidization and fuel combustion may reduce the overall energy consumption and CO_(2)-capture *** this paper,the fundamental structure of a self-designed 130 t·h^(-1) pure-oxygen combustion circulating fluidized bed(CFB)boiler was provided,and the computational particle fluid dynamics method was used to analyze the gas-solid flow characteristics of this new-concept boiler under different working *** results indicate that through the careful selection of design or operational parameters,such as average bed-material size and fluidization velocity,the pure-oxygen combustion CFB system can maintain the ideal fluidization state,namely significant internal and external particle ***,the contraction section of the boiler leads to the particle backflow in the lower furnace,resulting in the particle suspension concentration near the wall region being higher than that in the center ***,the upper furnace still retains the classic core-annulus flow *** addition to increasing solid circulation rate by reducing the average bed-material size,altering primary gas ratio and bed inventory can also exert varying degrees of influence on the gas-solid flow characteristics of the pure-oxygen combustion CFB boiler.

关键词： Circulating fluidized bed Pure-oxygen combustion Gas-solid flow characteristics Simulation CO_(2)capture

g-C_(3)N_(4)/TiO_(2-X) heterojunction with high-efficiency carrier separation and multiple charge transfer paths for ultrasensitive SERS sensing

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Chinese Chemical Letters 2024年第10期35卷 524-529页

作者： Xin Jiang Han Jiang Yimin Tang Huizhu Zhang Libin Yang Xiuwen Wang Bing Zhao College of Chemistry and Chemical Engineering Technology Innovation Center of Industrial Hemp for State Market RegulationQiqihar UniversityQiqihar 161006China College of Pharmacy Jjiamusi UniversityJjiamusi 154007China State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

The combination of interface engineering and defect engineering is a promising strategy for developing new semiconducting surface-enhanced Raman scattering(SERS)***,an organic/inorganic hybrid g-C_(3)N_(4)/TiO_(2-X)heterojunction with synchronous generation of strong interface effect and abundan surface oxygen vacancy(OV)defect was prepared by a simple sol-hydrothermal procedure with a help of *** to the improved substrate-to-molecule charge transfer(CT)from joint contribution of high efficiency carrier separation induced by strong interface coupling effect and multiple CT paths derived from abundant surface OV,g-C_(3)N_(4)/TiO_(2-X)substrate exhibits greatly enhanced SERS effect for non-resonan4-mercaptobenzoic acid(4-MBA)*** enhancement factor of g-C_(3)N_(4)/TiO_(2-X)substrate for 4-MBA i as high as 5.57×10^(6),and the substrate exhibits ultra-high stability and excellent spectral reproducibility More meaningfully,the developed g-C_(3)N_(4)/TiO_(2-X)heterojunction can be used to execute an ultrasensitive detection for antibiotic residues in real water system,even comprehensive evaluation of multi-componen residues.

关键词： SERS Semiconductor Heterojunction Surfacedefect Detection

All-Encompassing Approach to Food Practiced in china

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china News Release 2024年第6期 14-19页

作者： Long Wenjin Zhao Yuhan center for china's Agricultural Products market research at china Agricultural University(CAU) College of Economics and Management at CAU

The Central Rural Work Conference in 2015 proposed the concept of adopting an all-encompassing approach to agriculture and *** then on,the concept has appeared time and again in national conferences,documents,and even *** October 2022,when the 20th National Congress of the Communist Party of china(CPC)was held in Beijing,the concept of an allencompassing approach to food appeared in its *** report also called for effort to develop protected agriculture,or facility agriculture,and build a diversified food supply system.

关键词： Rural agriculture protected