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Event Detection and Identification of Influential Spreaders in Social Media Data Streams

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Big Data Mining and Analytics 2018年第1期1卷 34-46页

作者： Leilei Shi yan Wu lu Liu Xiang sun Liang Jiang School of Computer Science and Telecommunication Engineering Jiangsu University Department of Computing and Mathematics University of Derby

Microblogging, a popular social media service platform, has become a new information channel for users to receive and exchange the most up-to-date information on current events. Consequently, it is a crucial platform for detecting newly emerging events and for identifying influential spreaders who have the potential to actively disseminate knowledge about events through microblogs. However, traditional event detection models require human intervention to detect the number of topics to be explored, which significantly reduces the efficiency and accuracy of event detection. In addition, most existing methods focus only on event detection and are unable to identify either influential spreaders or key event-related posts, thus making it challenging to track momentous events in a timely manner. To address these problems, we propose a Hypertext-Induced Topic Search(HITS) based Topic-Decision method(TD-HITS), and a Latent Dirichlet Allocation(LDA) based Three-Step model(TS-LDA). TDHITS can automatically detect the number of topics as well as identify associated key posts in a large number of posts. TS-LDA can identify influential spreaders of hot event topics based on both post and user *** experimental results, using a Twitter dataset, demonstrate the effectiveness of our proposed methods for both detecting events and identifying influential spreaders.

关键词： event detection microblogging Hypertext-Induced Topic Search(HITS) Latent Dirichlet Allocation(LDA) identification of influential spreader

A 65-nm low-power high-linearity Σ△ ADC for audio applications

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Science China(Information Sciences) 2014年第4期57卷 201-207页

作者： LIAO lu sun Ying HAN yan LIANG Guo luO Hao LIU XiaoPeng Institute of Microelectronics and Photoelectronics Zhejiang University

This paper presents a low-power high linearity Σ△ analog-to-digital converter(ADC)for audio *** adopting low noise large output swing operational amplifiers in a 2-1 cascaded modulator,not only can the noise floor be reduced,but the input signal range can also be enlarged.A low-power,area-efficient digital decimation filter was also designed to decrease the area and the power *** ADC was fabricated in the SMIC 65 nm single-poly-eight-metal(1P8M)mixed-signal complementary metal-oxide-semiconductor(CMOS)process with a die area of 0.36 *** results showed that a 90 dB peak signal to noise plus distortion ratio(SNDR)and a 93 dB dynamic range(DR)were achieved over the 22.05 kHz audio *** power dissipation was 2.2 mW from 1.2 V power supply,which is suitable for audio codec applications.

关键词： modulator decimation filter low-power linearity audio ADC

A novel pathway for the preparation of Mg metal from magnesia

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Journal of Magnesium and Alloys 2022年第10期10卷 2847-2856页

作者： Zhimin Zhang Xuchen lu yan yan State Key Laboratory of Multi-phase Complex systems Institute of Process EngineeringChinese Academy of ScienceHaidian DistrictBeijing 100190PR

High-purity anhydrous magnesium chloride was prepared from magnesia and ammonium *** chlorination process was analyzed and then the critical stages affecting the purity of anhydrous magnesium chloride were *** effect of sample dimension on the above critical stages was investigated *** purity guarantee mechanism of anhydrous magnesium chloride was *** that,magnesium metal was obtained via electrolyzing the anhydrous magnesium chloride-containing molten *** new process for the continuous production of magnesium metal from magnesia was proposed and *** incomplete chlorination reaction and the hydrolysis of anhydrous magnesium chloride are the two critical stages affecting the purity of the anhydrous magnesium *** dimension of the sample can influence reaction process and reaction mechanism,and thus the problems of incomplete chlorination reaction and hydrolysis can be solved *** magnesia content in anhydrous magnesium chloride was below 0.1 wt.%when the ratio of height to diameter of the sample was over *** content of impurities in the magnesium metal obtained met the specifications of the product *** current efficiency was(94.7±1.8)%and the electricity consumption was(9107±97)kW h/t.

关键词： Magnesium Electrolysis Anhydrous magnesium chloride Hydrolysis

Cataclastic rheology of carbonate rocks

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Science China Earth Sciences 2005年第8期48卷 1227-1233页

作者： lu Xiancai sun yan SHU Liangshu GU Lianxing GUO Jichun ZHU Wenbin State Key Laboratory of Mineral Deposits Research Department of Earth SciencesNanjing UniversityNanjing 210093China

Based on the knowledge of the shallow-level mylonitization of detrital rocks and intrusive rocks,the poorly-known cataclastic rheology of carbonate rocks is discussed compre-hensively in this *** cases taken from eastern China are analyzed in various aspects including ductile-brittle fault zone,rock texture and structure,clastomylonite layer,leucocratic stress minerals,and frictional *** is proposed that the cataclastic flow structure represented by clastomylonite texture is a cooling pattern of flow assemblage charac-terized by cooling metamorphism,cooling mylonite and cooling stress *** a pattern is formed generally in mildly reducing physicochemical environments,and is commonly related to regional tectonism and mesothermal and epithermal mineralization.

关键词： carbonate rock cataclastic rheology clastomylonite ductile-brittle fault zone.

热塑性纤维素与PVA混溶性的分子动力学模拟

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原子与分子物理学报 2025年第3期42卷 149-158页

作者：冯彦洪陈帅杰孙航华南理工大学机械与汽车工程学院聚合物新型成型装备国家工程研究中心聚合物成型加工工程教育部重点实验室广东省高分子先进制造技术及装备重点实验室广州510000

首次提出了将氧化还原改性纤维素(Oxidation-reduction modified cellulose,ORC)与聚乙烯醇(Poly(vinyl alcohol),PVA)共混进行制备复合材料,并采用分子动力学模拟研究了ORC与PVA的混溶性.对分子链间相互作用能和氢键数量分析发现,随着... 详细信息

首次提出了将氧化还原改性纤维素(Oxidation-reduction modified cellulose,ORC)与聚乙烯醇(Poly(vinyl alcohol),PVA)共混进行制备复合材料,并采用分子动力学模拟研究了ORC与PVA的混溶性.对分子链间相互作用能和氢键数量分析发现,随着改性程度增加,ORC与PVA会产生更强烈的相互作用,这促进了组分间的混溶.当ORC的改性程度达到40%后,ORC与PVA的溶解度参数差值为2.02(J/cm^(3))^(1/2),达到混溶条件.根据Flory-Huggins理论确定了醇解度为88%和99%的PVA与ORC的混溶性,结果表明PVA(88%)与ORC的混溶性更好.对共混体系中形成氢键原子的径向分布函数分析发现,醋酸乙烯酯重复单元上的羰基更倾向与ORC形成分子链间氢键,而乙烯醇重复单元上的羟基更倾向形成分子链内氢键,这促使PVA(88%)/ORC共混体系中形成更多的分子链间氢键,从而混溶性更好.研究结果可为ORC/PVA复合材料的制备提供理论指导.

关键词：混溶性氧化还原改性纤维素分子动力学聚乙烯醇

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Recent advances in mRNA vaccine delivery

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Nano Research 2018年第10期11卷 5338-5354页

作者： lu Tan Xun sun Key Laboratory of Drug Targeting and Novel Drug Delivery System Ministry of Education West China School of Pharmacy SichuanUniversity Chengdu 61004 I China

In recent years, messenger RNA （mRNA） vaccines have been intensively studied in the fields of cancer immunotherapy and infectious diseases because of their excellent efficacy and safety profile. Despite significant progress in the rational design of mRNA vaccines and elucidation of their mechanism of action, their widespread application is limited by the development of safe and effective delivery systems that protect them from ubiquitous ribonucleases （RNases）, facilitate their entry into cells and subsequent escape from endosomes, and target them to lymphoid organs or particular cells. Some mRNA vaccines based on lipid carriers have entered clinical trials. Vaccines based on polymers, while not as clinically advanced as lipid vectors, show considerable potentials. In this review, we discuss the necessity of formulating mRNA vaccines with delivery systems, and we provide an overview of reported delivery systems.

关键词： messenger RNA (mRNA) vaccines delivery systems polymer lipid

Enhanced cycle stability of aprotic Li-O_(2) batteries based on a self-defensed redox mediator

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Chinese Chemical Letters 2024年第3期35卷 449-452页

作者： Guiru sun yan Wang Daming yang Zexu Zhang Wei lu Ming Feng Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103China College of Information Technology Jilin Engineering Research Center of Optoelectronic Materials and DevicesJilin Normal UniversitySiping 136000China

LiBr as a promising redox mediator(RM)has been applied in Li-O_(2)batteries to improve oxygen evolution reaction kinetics and reduce ***,the redox shuttle of Br_(3)^-can induce the unexpected reactions and thus cause the degradation of LiBr and the corrosion of Li anode,resulting in the poor cyclability and the low round-trip ***,MgBr_(2)is firstly employed with dual functions for Li-O_(2)batteries,which can serve as a RM and a SEI film-forming *** Br^(–)is beneficial to facilitating the decomposition of Li_(2)O_(2)and thus decreasing the ***,a uniform SEI film containing Mg and MgO generates on Li anode surface by the in-situ spontaneous reactions of Mg^(2+)and Li anode in an O_(2)environment,which can suppress the redox shuttle of Br_(3)^-and improve the interface stability of Li anode and *** from these advantages,the cycle life of Li-O_(2)battery with MgBr_(2)electrolyte is significantly extended.

关键词： MgBr_(2) Redox mediator Redox shuttle Li anode SEI film

Upper crustal P-wave velocity structure beneath two volcanic areas in northern Iran

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Science China Earth Sciences 2017年第4期60卷 786-795页

作者： lu yan CHEN Ling Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China State Key Laboratory of Lithospherie Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China

Detailed information about the crustal structure is essential for better understanding the occurrence and mechanisms of earthquakes and *** we present a study of the upper crustal P-wave velocity structure of two seismically and volcanically active areas in northern Iran using the two-dimensional Pg travel time tomography *** imaging results suggest low velocities in the upper crust beneath the Damavand and Sahand-Sabalan volcanic areas in the central and western parts of northern Iran,*** upper crustal low velocities in these two areas roughly coincide with previously imaged low Pn velocity anomalies,suggesting that the Late Cenozoic volcanic activity was probably caused by the upwelling of hot materials from the *** image feature of the Pg velocity structure beneath the Sahand-Sabalan volcanic area further indicates that the hot materials stored in the upper crust beneath Sahand may be larger in size than those stored beneath *** of the Pg velocity images with the earthquake distribution in north Iran suggests that earthquakes mainly occur at moderately low velocity or low to high velocity boundary areas instead of significantly low or high velocity *** anisotropy results show that the Pg wave fast direction is consistent with the GPS direction at high Pg velocity areas and the fast direction is inconsistent with the GPS direction but consistent with the strike direction of faults at low velocity *** new upper crustal structural images provide the basic observation for better understanding of the regional seismicity and volcanism,and link the surface geological phenomena to deep crustal and mantle processes associated with the active tectonics in northern Iran.

关键词： Equatorial ionization anomaly Sudden stratospheric warming Ionosphere

Towards Data-Driving Multi-View Evaluation Framework for Scratch

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Tsinghua Science and Technology 2024年第2期29卷 517-528页

作者： Xiaolin Chai yan sun yan Gao Department of Computer Science Beijing University of Posts and TelecommunicationBeijing 100876China Intellectual Property Institute Shandong Polytechnic CollegeJining 272067China

As one of the most popular visual programming languages,Scratch has a lot of evaluation around *** evaluation can help programmers understand their projects *** the same time,it can also provide a reference for them to browse other projects in the online *** of the existing evaluations on Scratch are carried from three perspectives:Computational Thinking(CT)ability,visual presentation aesthetics,and code *** them,the assessment of CT and code quality is mainly carried out from the program script,while the evaluation of visual aesthetics is analyzed from the perspective of image sequences generated by project *** single-view evaluation focuses on the performance of a program in a certain aspect and is *** this paper,we propose a multi-view evaluation framework to integrate various evaluations using different *** quantitatively analyze the assessment of different views driven by *** with overall evaluations that represent human opinions,we analyze their differences and *** experiments,we determine the weights of different integration policies,the proposed multi-view evaluation method can generate evaluation results similar to human opinions.

关键词： Scratch Computational Thinking(CT) visual aesthetic static analysis integration policy machine learning