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A credible traffic prediction method based on self-supervised causal discovery

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Science China(Information Sciences) 2024年第5期67卷 244-258页

作者： dan WANG Yingjie LIU Bin song State Key Laboratory of Integrated Services Networks Xidian University

Next-generation wireless network aims to support low-latency, high-speed data transmission services by incorporating artificial intelligence(AI) technologies. To fulfill this promise, AI-based network traffic prediction is essential for pre-allocating resources, such as bandwidth and computing power. This can help reduce network congestion and improve the quality of service(QoS) for users. Most studies achieve future traffic prediction by exploiting deep learning and reinforcement learning, to mine spatio-temporal correlated variables. Nevertheless, the prediction results obtained only by the spatio-temporal correlated variables cannot reflect real traffic changes. This phenomenon prevents the true prediction variables from being inferred, making the prediction algorithm perform poorly. Inspired by causal science, we propose a novel network traffic prediction method based on self-supervised spatio-temporal causal discovery(SSTCD). We first introduce the Granger causal discovery algorithm to build a causal graph among prediction variables and obtain spatio-temporal causality in the observed data, which reflects the real reasons affecting traffic ***, a graph neural network(GNN) is adopted to incorporate causality for traffic prediction. Furthermore,we propose a self-supervised method to implement causal discovery to to address the challenge of lacking ground-truth causal graphs in the observed data. Experimental results demonstrate the effectiveness of the SSTCD method.

关键词： wireless network traffic prediction causal discovery self-supervised

Versatile zeolite overlayer on ZnO film enabling high-performance bilayer NO_(2) sensoring

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Nano Research 2024年第10期17卷 9193-9201页

作者： Tianshuang Wang Yiheng Li dan Li Peng Sun Xiaowei song Geyu Lu Jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University2699 Qianjin StreetChangchun 130012China State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China International Center of Future Science Jilin University2699 Qianjin StreetChangchun 130012China

Bilayer structure with functional overlayer has been commonly adopted to resolve the issue of moisture poisoning in ***,the conventional overlayers always suffer from blocking access of gas molecules to sensing layer due to lacking porosity and deteriorated adsorption ***,taking advantages of the well-defined porous structure and hydrophobic nature of pure silica zeolite,we assembled an overlayer of Pd-PdO clusters-encapsulated mesoporous silicalite-1(MFI)zeolite(named M-S-1)on ZnO sensing layer,to prevent moisture poisoning,and enhance gas diffusion and adsorption *** inherent capability of MFI zeolite to incorporate monodispersed nanometric(ca.3 nm)Pd-PdO cluster in its void space is of great importance for the NO_(2) *** Pd-PdO@M-S-1 overlayer can attain negligible moisture interference to the ZnO layer without significantly altering the gas selectivity and baseline resistance,and enhance gas ***,the Pd-PdO@M-S-1/ZnO bilayer sensor can ultra-selectively(S_(nitrogen dioxide)/S_(interference gas)>4),and ultra-stably detect trace level of NO_(2)(9.5 ppb)at low temperature(370 K)under high levels of humidity(90%RH).This work exemplifies a next-generation solution to design bilayer sensors using zeolite overlayer for eliminating the humidity dependence of the gas-sensing properties.

关键词： zeolites metal clusters bilayer structure NO_(2)chemiresistor

Epidemiological Characteristics of Notifiable Infectious Diseases among Foreign Cases in China,2004–2017

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Biomedical and Environmental Sciences 2020年第6期33卷 421-430页

作者： WU yue LI Zhen Jun yu Shi Cheng CHEN Liang WANG Ji Chun QIN yu song yu dan George F.GAO DONG Xiao Ping WANG Li Ping ZHANG Qun HE Guang Xue Chinese Center for Disease Control and Prevention Beijing 102206China National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionState Key Laboratory of Infectious Disease Prevention and ControlCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesBeijing 102206China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savald Medical School University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases(Zhejiang University)National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Objective We aimed to assess the features of notifiable infectious diseases found commonly in foreign nationals in China between 2004 and 2017 to improve public health policy and responses for infectious *** We performed a descriptive study of notifiable infectious diseases among foreigners reported from 2004 to 2017 in China using data from the Chinese National Notifiable Infectious Disease Reporting System(NNIDRIS). Demographic, temporal-spatial distribution were described and *** A total of 67,939 cases of 33 different infectious diseases were reported among *** diseases were seen in 31 provinces of China and originated from 146 countries of the world. The infectious diseases with the highest incidence number were human immunodeficiency virus(HIV) of18,713 cases, hepatitis B(6,461 cases), hand, foot, and mouth disease(6,327 cases). yunnan province had the highest number of notifiable infectious diseases in foreigners. There were different trends of the major infectious diseases among foreign cases seen in China and varied among *** This is the first description of the epidemiological characteristic of notifiable infectious diseases among foreigners in China from 2004 to 2017. These data can be used to better inform policymakers about national health priorities for future research and control strategies.

关键词： Foreign cases Notifiable infectious diseases Epidemiological characteristics

Preparation and characterization of high-reactivity explosive-based nano-boron microspheres

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Particuology 2024年第10期93卷 125-136页

作者： Chen Dong Yi Wang Kanghui Jia dan song Xiaolan song Chongwei An School of Materials Science and Engineering North University of ChinaTaiyuan030051China Jinxi Group Shanxi Jiangyang Chemical Co. Ltd.Taiyuan030051China China Ordnance Institute of Science and Technology Beijing100089China School of Environment and Safety Engineering North University of ChinaTaiyuan030051China

Boron nanoparticles,with their remarkably high gravimetric and volumetric calorific values,emerge as the most promising fuel in energetic ***,challenges such as susceptibility to oxidation,high ignition temperature,and low combustion efficiency have constrained their further *** this study,we fabricated high explosives based nano-boron microspheres with uniform size using the electrostatic spray method,in which the boron nanoparticles and high explosives(CL-20 or PETN)are closely bonded together by fluorinated polymer(F2602)and evenly *** results indicated that the microspheres exhibited high sphericity and showed an enhanced antioxidant *** addition of high-energy explosives not only reduced the thermal oxidation temperature of nano-boron powder within the microspheres but also significantly enhanced the pressurization ***,the microspheres with added high-energy explosives released more energy during the combustion *** to physically mixed samples,electrostatically sprayed microspheres with a uniform microstructure still exhibited higher ***,the design and synthesis of microspheres with controllable structures using the electrostatic spray method show promising application prospects.

关键词： Nano-boron CL-20 PETN Electrospraying Ignition and combustion

Microstructure and mechanical properties of Co-28Cr-6Mo-0.22C investment castings by current solution treatment

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China Foundry 2024年第4期21卷 369-378页

作者： Ze-yu dan Jun Liu Jian-lei Zhang Yan-hua Li yuan-xin Deng yun-hu Zhang Chang-jiang song Center for Advanced Solidification Technology School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Wuxi CastPro Precision Co. Ltd.Wuxi 214105JiangsuChina

This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment *** findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower *** optimal conditions for solution treatment are determined as a solution temperature of 1,125°C and a holding time of 5.0 *** these parameters,the size and volume fraction of precipitated phases in the investment castings are measured as6.2μm and 1.1vol.%.The yield strength,ultimate tensile strength,and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa,760 MPa,and 12.6%,*** values exceed those obtained with the conventional solution treatment at 1,200°C for 4.0 *** findings suggest a phase transformation of M_(23)C_(6)→σ+C following the current solution treatment at 1,125°C for 5.0 *** comparison,the traditional solution treatment at 1,200°C for 4.0 h leads to the formation of M_(23)C_(6)and M_(6)C *** is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation *** modification lowers the phase transition temperature of the M_(23)C_(6)→σ+C reaction,thereby facilitating the dissolution of *** a result,the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods.

关键词： CoCrMo alloy investment castings current solution treatment microstructure mechanical property carbide

Designing high piezoelectric properties at the BaTiO_(3)–PbZrO_(3)–PbTiO_(3)phase boundary by Landau–Devonshire theory

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Journal of Advanced Dielectrics 2024年第2期14卷 33-41页

作者： yu song Xiaoming Shi dan Li Jing Wang Houbing Huang School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081P.R.China Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing 100081P.R.China School of Electronic Information and Electrical Engineering Chengdu University Chengdu 610100P.R.China

Ferroelectric materials possessing exceptional piezoelectric attributes have garnered widespread utilization in various *** solution systems improve piezoelectric properties through multiphase mixing,but the methodologies for effective design remain *** on the Landau–Devonshire theory,we propose a theoretical design *** materials with morphotropic phase boundary(MPB)compositions are added with new elements to increase the free energy of the original stabilized phase and lower the energy barrier(EB).Flatter EBsand higher piezoelectric coefficients are found at the phase boundaries of the ternary *** calculating the phase diagram,piezoelectric coefficient,dielectric constant,polarization,and EBs,we reveal the origin of the highest piezoelectric coefficient at the phase *** study underscores the importance of the EBs for polarization rotation in characterizing piezoelectric properties and proposes a theoretical design method for exploring materials with high piezoelectric coefficients.

关键词： BaTiO_(3)-PbZrO_(3)-PbTiO_(3) piezoelectric properties free energy barrier thermodynamic calculation Landau-Devonshire theory

Trial application of the envelope method to the potential ambiguity problem

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Nuclear Science and Techniques 2024年第1期35卷 73-80页

作者： Li-yuan Hu yu-Shou song Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering UniversityHarbin 150001China College of Nuclear Science and Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory of Nuclear Safety and Advanced Nuclear Energy Technology Ministry of Industry and Information TechnologyHarbin 150001China

The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering *** a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering *** contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,***,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity *** this study,we conducted a trial application of the envelope method to the potential ambiguity *** envelope method was improved by including uncertainties in the experimental *** colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the *** each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is *** calculated angular distributions were decomposed into nearside and farside scattering *** the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside *** capability of the envelope method to analyze the potential ambiguities was also discussed.

关键词： Elastic scattering Optical potential ambiguities Envelope method Nearside/farside decomposition

Synthesis Chemistry & Performance Enhancement of Critical Inorganic Functional Materials

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Chemical Research in Chinese Universities 2024年第3期40卷 343-345页

作者： WANG dan yu Ranbo State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science&Technology BeijingBeijing 100083P.R.China

The development of human economy and society relies on the advancement of materials,and the research of advanced materials continuously drives industrial changes,giving rise to a new wave of global scientific and technological *** plays a significant role in the field of materials research and industry,however,the increasing prominence of key strategic materials being controlled by external forces has become a bottleneck issue that hinders national economic and social development as well as national security.

关键词： hinder continuously forces

Celebrating 40 Years of Chemical Research in Chinese Universities

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Chemical Research in Chinese Universities 2024年第4期40卷 561-563页

作者： yu Jihong WANG dan State Key Laboratory of Inorganic Synthesis and Preparative Chemistry International Center of Future ScienceJilin UniversityChangchun 130012P.R.China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China

Chemical Research in Chinese Universities was founded in 1984 as a comprehensive academic journal in the field of *** has since become a repository of intellectual treasures,documenting the evolving landscape of chemical science within the academic *** the past 40 years,Chemical Research in Chinese Universities has witnessed the rapid development of chemical research in universities.

关键词： chemistry. landscape journal