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Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels

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Chinese Physics B 2024年第3期33卷 690-699页

作者：谢笑笑霍良安董雅芳程英英 Business School University of Shanghai for Science and TechnologyShanghai 200093China School of Intelligent Emergency Management University of Shanghai for Science and TechnologyShanghai 200093China School of Management Henan University of Science and TechnologyLuoyang 471023China

While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network *** this study,we construct a new two-layer coupling model to explore the interactions between information and *** upper layer describes the diffusion of disease-related information,and the lower layer represents the disease *** then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the ***,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical *** findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion ***,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease *** study provides valuable insights into policymakers for developing outbreak prevention and control strategies.

关键词： information diffusion disease transmission asymmetric activity levels quarantine strength

Ultrafast optical investigation of carrier and spin dynamics in low-dimensional perovskites

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Science China(Technological Sciences) 2024年第1期67卷 2-18页

作者： FU JinYue JIANG ying fang HongHua Key Laboratory for Micro-Nano Physics and Technology of Hunan Province School of Physics and ElectronicsHunan UniversityChangsha 410012China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Low-dimensional perovskite(PVK)materials have attracted significant research interest,because of their quantum-confined effect,tunable band gap structures,and higher stability than that of three-dimensional(3D)*** semiconductor optoelectronic devices,high speed and small size are closely *** development of high-speed devices requires researchers to fully understand the properties of materials,especially the dynamic processes such as carrier recombination,separation,and transport,which often play a crucial role in the performance of *** an indispensable part of dynamic research,spin relaxation is also of great significance in studying the properties of materials and explore possible *** halide PVK materials have strong spin-orbit coupling(SOC),which provides a basis for information storage and processing by using spin degrees of ***,studying the carrier and spin dynamics of low-dimensional PVKs is an effective way to understand the internal properties of low-dimensional PVKs *** paper summarizes the latest research progress on the ultrafast carrier and spin dynamics in low-dimensional PVKs,to comprehensively understand their carrier and spin behaviors and present an outlook for relevant studies in this area.

关键词： low-dimensional perovskites carrier dynamics spin dynamics optoelectronic devices

Compatibility evaluation between waterborne epoxy resin and SBR latex modified asphalt emulsion

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 160-171页

作者： Jianhua Yang Zhengqi Zhang ying fang Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064China

Good compatibility between waterborne epoxy resin(WER)modifier and styrene-butadiene rubber(SBR)latex modified asphalt emulsion(SBRE)is an essential premise for good pavement performance of WER and SBR latex compositely modified asphalt emulsion(WSAE).This study aims to explore the compatibility between WER modifier and *** achieve the goal,several WER modifiers produced by two methods were first selected to modify SBRE,thus the WSAEs were ***,storage stability and workability of the WSAEs themselves,and high-temperature performance,rheological behavior and temperature sensitivity of their evaporated residues were compared and evaluated via performing a series of experiments,respectively,thus the WER modifier possessing an optimal modification effect was *** show that the storage stability of WSAEs is sensitive to the amount of *** incorporation of 1%WERs by the mass of SBRE improves the storage stability of SBRE,while WERs that exceed 1%weaken its storage *** the WERs reach 3%and 4%,the 5 d storage stability of prepared WSAEs will be beyond the limitation of *** WERs into SBRE negatively affects the workability of SBRE,and the workability of WSAEs is adversely influenced by the WERs content and the storage *** ensure the construction,the WSAEs with 3%and 4%WERs should not be stored for more than 36 h and 48 h,*** WERs effectively improve the high-temperature performance of SBRE residue,especially the 3%***,the WERs notably enhance the rheological property and thermal stability of SBRE *** contrast,the WER modifier produced by chemically modified method has a smaller adverse impact on the storage stability and workability of WSAE,and a larger enhancement on the high-temperature performance,rheological property and thermal stability of SBRE residue,which is thus recommended to modify SBRE.

关键词： Waterborne epoxy resin SBR modified asphalt emulsion Workability Rheological property Temperature sensitivity Compatibility evaluation

An axisymmetric characteristic model for enhancing prediction of centrifugal compressor characteristics

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Chinese Journal of Aeronautics 2024年第4期37卷 203-215页

作者： Peng REN Xiangjun fang Zeyu JIAO ying HAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Guangdong Key Laboratory of Modern Control Technology Institute of Intelligent ManufacturingGuangdong Academy of SciencesGuangzhou 510070China

Rapid and accurate determination of compressor characteristic maps is essential for the initial design of centrifugal compressors in aircraft power systems. The accuracy of existing methodologies, which rely on combinations of loss models, varies significantly depending on the compressor's geometry and operational range. This variance necessitates substantial experimental or Computational Fluid Dynamics(CFD) data for coefficient calibration. To address this challenge, this study presents an axisymmetric characteristic model for compressor performance assessment. This model incorporates the factors of blade angle, meridional passage area, and the radial deflection angle of meridional streamlines of the compressor. These factors are derived from fundamental aerodynamic equations encompassing mass, momentum, and energy conservation of the compressor. In contrast to conventional one-dimensional approaches, the proposed method reduces the number of loss coefficients and more effectively accounts for the impact of geometric alterations on centrifugal compressor properties. Furthermore, the model reduces dependence on experimental and CFD data. Efficacy of the model is validated using experimental data from four distinct types of centrifugal compressors. Correlation analysis reveals that the model's coefficients can be expressed as functions of the ratio of the Reynolds number to the impeller tip speed. This ratio serves as a characteristic parameter for the design and optimization of centrifugal compressors. Consequently, the proposed method offers an efficient and accurate means for the quick computation of centrifugal compressor characteristics. This is of great significance for improving the efficiency of centrifugal compressors and reducing energy consumption.

关键词： Centrifugal compressor Positive problem Characteristic prediction Aerodynamic characteristic Axisymmetric model

Navigation Finsler metrics on a gradient Ricci soliton

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 266-275页

作者： LI ying MO xiao-huan WANG xiao-yang Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Pure and Applied Mathematics School of Mathematical SciencesPeking UniversityBeijing 100871China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China

In this paper,we study a class of Finsler metrics defined by a vector field on a gradient Ricci *** obtain a necessary and sufficient condition for these Finsler metrics on a compact gradient Ricci soliton to be of isotropic S-curvature by establishing a new integral *** we determine the Ricci curvature of navigation Finsler metrics of isotropic S-curvature on a gradient Ricci soliton generalizing result only known in the case when such soliton is of Einstein *** its application,we obtain the Ricci curvature of all navigation Finsler metrics of isotropic S-curvature on Gaussian shrinking soliton.

关键词： gradient Ricci soliton navigation Finsler metric isotropic S-curvature Ricci curvature Gaussian shrinking soliton

The current situation of semen analysis in China,based on a survey of 296 laboratories

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Asian Journal of Andrology 2024年第2期26卷 220-221页

作者： Long-Long Fu ying Liu xiao-Wei Wang fang Zhou ying Guo Wen-Hong Lu Yi-Qun Gu National Health Commission Key Laboratory of Male Reproductive Health Reproductive Health Research CenterNational Research Institute for Family PlanningBeijing 100081China Institute of Pediatric Research Children's Hospitalof Soochow UniversitySuzhou 215025China

Dear Editor,Semen analysis is a basic test to assess male fertility and is a fundamental test in assisted reproductive *** the first publication of World Health Organization(WHO)Laboratory Manual of Human Semen and Sperm-Cervical Mucus Interaction in 1980,to the publication of the WHO Manual,6th edition in 2021,these 40 years have been recognized as providing a global standard that is widely used in research and clinical laboratories *** WHO Manual,6th edition in Chinese,which we have been authorized by the WHO to translate,will be published soon.

关键词： technology. analysis translate

How to implement a knowledge graph completeness assessment with the guidance of user requirements

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Journal of Systems Engineering and Electronics 2024年第3期35卷 679-688页

作者： ZHANG ying xiao Gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge graphs, quality assessment is particularly important. As an important thing of quality assessment, completeness assessment generally refers to the ratio of the current data volume to the total data *** evaluating the completeness of a knowledge graph, it is often necessary to refine the completeness dimension by setting different completeness metrics to produce more complete and understandable evaluation results for the knowledge ***, lack of awareness of requirements is the most problematic quality issue. In the actual evaluation process, the existing completeness metrics need to consider the actual application. Therefore, to accurately recommend suitable knowledge graphs to many users, it is particularly important to develop relevant measurement metrics and formulate measurement schemes for completeness. In this paper, we will first clarify the concept of completeness, establish each metric of completeness, and finally design a measurement proposal for the completeness of knowledge graphs.

关键词： knowledge graph completeness assessment relative completeness user requirement quality management

Constructing inter-diffusive PtCuNi/WO_(3)interface to enhance the catalytic activity and stability in oxygen reduction

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Tungsten 2024年第2期6卷 293-303页

作者： Hao-Zhe Xu Dong Li ying Chen Pin fang xiao-Xing Ke Olga Demidenko Yu-Jing Li Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications Experimental Center of Advanced MaterialsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Scientifi c-Practical Materials Research Centre National Academy of Sciences of Belarus220072 MinskBelarus

Platinum-group-metal-based alloy nanocrystals have been considered as the most effi cient catalysts for oxygen reduction reaction(ORR).However,the poor stability issues limit their further deployment in *** oxide(WO_(3))has received attention due to its intrinsic electrochemical stability and proton absorption/desorption *** this work,we prepared PtCuNi/WO_(3)/C hybrid catalyst with inter-diff usive alloy/WO_(3)interface on *** catalyst exhibits enhanced activity and stability associated with the WO_(3)*** characterization results suggest that the increased activity originates from the complementary proton supply of non-stoichiometric H_(x)WO_(3).Moreover,WO_(3)prevents the particle from dissolution and detachment under vigorous electrochemical *** enhanced stability originates from the electronic interaction established between Pt and *** work provides new strategies to design high-performance ORR catalysts by taking the merits of WO_(3)。

关键词： Tungsten oxide PtCuNi Interface Electronic interaction

Experimental distillation of tripartite quantum steering with an optimal local filtering operation

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Photonics Research 2024年第3期12卷 552-562页

作者： QIAN-XI ZHANG xiao-XU fang HE LU School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China

Multipartite Einstein-Podolsky-Rosen(EPR)steering admits multipartite entanglement in the presence of uncharacterized verifiers,enabling practical applications in semi-device-independent *** applications generally require stronger steerability,while the unavoidable noise weakens steerability and consequently degrades the performance of quantum information ***,we propose the local filtering operation that can maximally distill genuine tripartite EPR steering from N copies of three-qubit generalized Greenberger-Horne-Zeilinger states,in the context of two semi-device-independent *** optimal filtering operation is determined by the maximization of assemblage *** and numerical results indicate the advantage of the proposed filtering operation when N is finite and the steerability of initial assemblages is ***,a proof-of-principle demonstration of two-copy distillation is realized with the optical *** advantage of the optimal local filtering operation is confirmed by the distilled assemblage in terms of higher assemblage fidelity with perfectly genuine tripartite steerable assemblages,as well as the greater violation of the inequality to witness genuine tripartite steerable *** results benefit the distillation of multipartite EPR steering in practice,where the number of copies of initial assemblages is generally finite.

关键词： filtering distillation optimal