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Chinese Physics B 2024年第4期33卷 160-171页

作者：卢倬成冯济 international Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China

A Weyl node is characterized by its chirality and *** develop a theory of how nth-order nonlinear optical conductivity behaves under transformations of anisotropic tensor and tilt, which clarifies how chirality-dependent and-independent parts of optical conductivity transform under the reversal of tilt and *** on this theory, we propose ferromagnetic Mn Bi2Te4as a magnetoelectrically regulated, terahertz optical device, by magnetoelectrically switching the chiralitydependent and-independent DC *** results are useful for creating nonlinear optical devices based on the topological Weyl semimetals.

关键词： nonlinear optical response topological Weyl semimetals chiral anomaly

GMAT:A Graph Modeling Method for Group Preference Prediction

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 475-493页

作者： Xiangyu Li Xunhua Guo Guoqing Chen international Business school Jinan UniversityZhuhai519070China school of Economics and Management Tsinghua UniversityBeijing100084China

Preference prediction is the building block of personalized services,and its implementation at the group level helps enterprises identify their target customers *** methods for preference prediction mainly focus on behavioral interactions to extract the associations between groups and products,ignoring the importance of other auxiliary records(e.g.,online reviews and social tags)in association *** paper proposes a novel method named GMAT for group preference prediction,aiming to collectively detect the sophisticated association patterns from user generated content(UGC)and behavioral *** doing so,we construct a tripartite graph to collaborate these two types of data,and design a deep-learning algorithm with mutual attention module for generating the contextualized representations of groups and *** experiments on two real-world datasets show that GMAT is superior to other baselines in terms of group preference ***,GMAT is able to improve prediction accuracy compared with its different variants,further verifying the proposed method’s effectiveness on association pattern detection.

关键词： Group preference UGC tripartite graph deep learning

Crowding-in or Crowding-out:How Infrastructure Investment Affects Household Consumption

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China Finance and Economic Review 2024年第1期13卷 43-66页

作者： Zhiyu Yan Yufei Yuan Yi Xue school of international Business and Economics University of International Business and Economics

This paper constructs a dynamic model of household consumption decisions and accordingly designs empirical analyses to identify how infrastructure investment affects private *** estimation results of provincial panel data reveal that infrastructure investment can not only indirectly promote household consumption through the income channel but also directly promote household consumption expansion through the expectations channel,with a significant"crowding-in"***,the effect is significantly weaker in provinces with a lower housing supply elasticity,showing the"crowding-out"pattern through the wealth *** survey data provide an explanation for individual *** investment has a greater pushing effect on house prices in provinces with a lower housing supply *** house price growth has significant"crowding-out"effects on the consumption of wealthy *** not only significantly weakens the driving effect of infrastructure investment on aggregate household consumption,but also increases wealth inequality in the long *** paper explains how infrastructure investment affects household consumption and the corresponding role played by house prices,providing empirical evidences for theoretical studies related to macro-regulatory policies in China.

关键词： infrastructure investment household consumption housing supply elasticity macro regulatory policies

A large-scale cold plasma jet: generation mechanism and application effect

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Plasma Science and Technology 2024年第4期26卷 1-8页

作者：崔伟胜张若兵 Shenzhen international Graduate school Tsinghua UniversityShenzhen 518055People’s Republic of China

Atmospheric pressure cold plasma jets(APCPJs) typically exhibit a slender, conical structure,which imposes limitations on their application for surface modification due to the restricted treatment area. In this paper, we introduce a novel plasma jet morphology known as the large-scale cold plasma jet(LSCPJ), characterized by the presence of both a central conical plasma jet and a peripheral trumpet-like diffuse plasma jet. The experimental investigations have identified the factors influencing the conical and the trumpet-like diffuse plasma jet, and theoretical simulations have shed light on the role of the flow field and the electric field in shaping the formation of the LSCPJ. It is proved that, under conditions of elevated helium concentration, the distributions of impurity gas particles and the electric field jointly determine the plasma jet’s morphology. High-speed ICCD camera images confirm the dynamic behavior of plasma bullets in LSCPJ, which is consistent with the theoretical analysis. Finally, it is demonstrated that when applied to the surface treatment of silicone rubber, LSCPJ can achieve a treatment area over 28 times larger than that of APCPJ under equivalent conditions. This paper uncovers the crucial role of impurity gases and electric fields in shaping plasma jet morphology and opens up the possibility of efficiently diversifying plasma jet generation effects through external electromagnetic fields. These insights hold the promise of reducing the generation cost of plasma jets and expanding their applications across various industrial sectors.

关键词： diffuse plasma jet flow field electric field surface treatment

Improved Twin Support Vector Machine Algorithm and Applications in Classification Problems

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China Communications 2024年第5期21卷 261-279页

作者： Sun Yi Wang Zhouyang Beijing University of Posts and Telecommunications School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and Telecommunications International School

The distribution of data has a significant impact on the results of *** the distribution of one class is insignificant compared to the distribution of another class,data imbalance *** will result in rising outlier values and ***,the speed and performance of classification could be greatly *** the above problems,this paper starts with the motivation and mathematical representing of classification,puts forward a new classification method based on the relationship between different classification *** with the vector characteristics of the actual problem and the choice of matrix characteristics,we firstly analyze the orderly regression to introduce slack variables to solve the constraint problem of the lone *** we introduce the fuzzy factors to solve the problem of the gap between the isolated points on the basis of the support vector *** introduce the cost control to solve the problem of sample ***,based on the bi-boundary support vector machine,a twostep weight setting twin classifier is *** can help to identify multitasks with feature-selected patterns without the need for additional optimizers,which solves the problem of large-scale classification that can’t deal effectively with the very low category distribution gap.

关键词： fuzzy ordered regression(OR) relaxing variables twin support vector machine

Recent progress about transmission electron microscopy characterizations on lithium-ion batteries

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Journal of Energy Chemistry 2024年第8期95卷 39-56,I0002页

作者： Yihang Liu Qiuyun Li Ziqiang Wang Institute of Materials Research Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518000GuangdongChina

With the rapid development of portable electronics,new energy vehicles,and smart grids,ion batteries are becoming one of the most widely used energy storage devices,while the safety concern of ion batteries has always been an urgent problem to be *** develop a safety-guaranteed battery,the characterization of the internal structure is indispensable,where electron microscopy plays a crucial *** on this,this paper summarizes the application of transmission electron microscopy(TEM)in battery safety,further concludes and analyzes the aspects of dendrite growth and solid electrolyte interface(SEI)formation that affect the safety of ion batteries,and emphasizes the importance of electron microscopy in battery safety research and the potential of these techniques to promote the future development of this *** advanced electron microscopy techniques and their prospects are also discussed.

关键词： Electron microscopy characterizations Lithium-ion batteries Dendrites SEI

Robust blind image watermarking based on interest points

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虚拟现实与智能硬件（中英文） 2024年第4期6卷 308-322页

作者： Zizhuo WANG Kun HU Chaoyangfan HUANG Zixuan HU Shuo YANG Xingjun WANG Tsinghua Shenzhen international Graduate school Tsinghua UniversityShenzhen 518071China

Digital watermarking technology plays an essential role in the work of anti-counterfeiting and ***,image watermarking algorithms are weak against hybrid attacks,especially geometric attacks,such as cropping attacks,rotation attacks,*** propose a robust blind image watermarking algorithm that combines stable interest points and deep learning networks to improve the robustness of the watermarking algorithm ***,to extract more sparse and stable interest points,we use the Superpoint algorithm for generation and design two steps to perform the screening *** first keep the points with the highest possibility in a given region to ensure the sparsity of the points and then filter the robust interest points by hybrid attacks to ensure high *** message is embedded in sub-blocks centered on stable interest points using a deep learning-based *** kinds of attacks and simulated noise are added to the adversarial training to guarantee the robustness of embedded *** use the ConvNext network for watermark extraction and determine the division threshold based on the decoded values of the unembedded *** extensive experimental results,we demonstrate that our proposed algorithm can improve the accuracy of the network in extracting information while ensuring high invisibility between the embedded image and the original cover *** with previous SOTA work reveals that our algorithm can achieve better visual and numerical results on hybrid and geometric attacks.

关键词： Blind watermarking Robust region selection Geometric distortion Deep learning

Registration system reform and initial public offering ownership preference:Evidence from China

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China Journal of Accounting Research 2024年第1期17卷 74-95页

作者： Xihao Wu Di Zhang Zhongxin Wu international Business school Hainan UniversityChina

Whether registration system reform(RSR)can curb administrative intervention and create a fair market environment has long been a concern in *** explore this issue from the perspective of the initial public offering(IPO)preference based on the entropy balancing method,and findings are as ***,an IPO ownership preference exists under approval *** is,state-owned enterprises(SOEs)are more likely than private enterprises to obtain IPO ***,RSR significantly changes this preference,especially for non-politically connected private ***,the post-IPO market performance of SOEs is inferior to that of private enterprises under approval system,thus excluding the view that approval is prioritized for SOEs because of superior ***,compared with SOEs,private enterprises are more likely to switch the issuance system from approval system to registration system;this change makes it easier for them to obtain IPO approval,indicating that private enterprise owners perceive the registration channel to be ***,the effect of RSR on IPO ownership preference mainly occurs in companies in three major urban agglomerations in China—the Pearl River Delta,the Yangtze River Delta,and the Beijing–Tian jin–Hebei region—and in technology-intensive ***,our findings reveal that RSR cultivates a fairer IPO approval process.

关键词： Registration system reform Administrative intervention Approval system IPO ownership preference

Reversible isomerization of donor-acceptor Stenhouse adduct derivatives in water through dendritic confinement

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Science China Chemistry 2024年第5期67卷 1636-1646页

作者： Jiaxing Zhang Qingyun Zhao Xinyan Su Afang Zhang Wen Li international Joint Laboratory of Biomimetic and Smart Polymers School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

Modulating reversible isomerization of hydrophobic dyes in aqueous solutions is greatly desired. Here we report on reversible isomerization of solvatochromic donor-acceptor Stenhouse adducts(DASAs) in water through the confinement from dendritic oligoethylene glycols(OEGs). Dendronization of DASAs with dendritic OEGs affords them characteristic thermoresponsiveness. These dendronized DASAs spontaneously isomerize in water from hydrophobic linear state into hydrophilic cyclic state at room temperature due to the strong hydration. However, hydrophobic microenvironment through thermally dehydration and collapse of the dendritic OEGs at elevated temperatures confines hydration of the DASA moieties and mediates their interactions with the collapsed hydrophobic OEG domains, affording their isomerization recovery in water efficiently from the hydrophilic cyclic state into the hydrophobic linear state. The confinement-mediated reversible isomerization of DASA moieties in water can be repeated through alternative photo-irradiation and thermal dehydrations, exhibiting excellent fatigue resistance.

关键词： dendrimers donor-acceptor Stenhouse adducts isomerization confinement thermoresponsiveness

Grassland-type ecosystem stability in China differs under the influence of drought and wet events

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Journal of Arid Land 2024年第5期16卷 615-631页

作者： CAO Wenyu BAI Jianjun YU Leshan school of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China international Business school Shaanxi Normal UniversityXi'an 710119China

Ecological stability is a core issue in ecological research and holds significant implications forhumanity. The increased frequency and intensity of drought and wet climate events resulting from climatechange pose a major threat to global ecological stability. Variations in stability among different ecosystemshave been confirmed, but it remains unclear whether there are differences in stability within the sameterrestrial vegetation ecosystem under the influence of climate events in different directions and ***'s grassland ecosystem includes most grassland types and is a good choice for studying this *** study used the Standardized Precipitation Evapotranspiration Index-12 (SPEI-12) to identify thedirections and intensities of different types of climate events, and based on Normalized DifferenceVegetation Index (NDVI), calculated the resistance and resilience of different grassland types for 30consecutive years from 1990 to 2019 (resistance and resilience are important indicators to measurestability). Based on a traditional regression model, standardized methods were integrated to analyze theimpacts of the intensity and duration of drought and wet events on vegetation stability. The resultsshowed that meadow steppe exhibited the highest stability, while alpine steppe and desert steppe had thelowest overall stability. The stability of typical steppe, alpine meadow, temperate meadow was at anintermediate level. Regarding the impact of the duration and intensity of climate events on vegetationecosystem stability for the same grassland type, the resilience of desert steppe during drought was mainlyaffected by the duration. In contrast, the impact of intensity was not significant. However, alpine steppewas mainly affected by intensity in wet environments, and duration had no significant impact. Ourconclusions can provide decision support for the future grassland ecosystem governance.

关键词： grassland ecosystem stability resistance resilience different climate types drought climate event wet climate event