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组合查询条件下的属性社区搜索

计算机应用与软件 2024年第4期41卷 38-45页

作者：王玲刘晓清何震瀛荆一楠复旦大学软件学院上海200438 复旦大学计算机科学技术学院上海200438

传统的属性社区搜索问题仅研究查询属性在结果社区中存在与否。为应对复杂查询场景的需求,研究了组合查询条件下的属性社区搜索问题:给定多属性集合,各属性至少需满足的数量以及社区大小的上限约束,搜索所有节点的最小度数最大化的社区... 详细信息

传统的属性社区搜索问题仅研究查询属性在结果社区中存在与否。为应对复杂查询场景的需求,研究了组合查询条件下的属性社区搜索问题:给定多属性集合,各属性至少需满足的数量以及社区大小的上限约束,搜索所有节点的最小度数最大化的社区。提出通用算法解决框架,并以此为基础,提出两个优化方法,分别是:基于属性特征的搜索空间优化,以减小搜索空间;基于结构特征的搜索顺序优化,以通过搜索顺序的调整进一步提升算法效率。实验结果表明,算法可找到符合组合查询条件的属性社区。在大规模数据集上,经过两个优化后的算法效率比原算法提升2~3倍,同时内存开销减少约50%。

关键词：社区搜索组合查询条件属性社区

数字化转型背景下金融风险监测与预警体系研究

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中国工程科学 2024年第3期26卷 196-206页

作者：张寒冰李智鑫荆一楠王晓阳吴杰柴洪峰复旦大学计算机科学技术学院上海200433 复旦大学金融科技研究院上海200433

当前,我国金融业数字化转型从多点突破进入深化和高质量发展的新阶段,需要协调包括管理部门、企业、个人在内的多元主体形成协同共治机制;针对数字化转型背景下产生的新型、复杂、潜在危害突出的金融风险问题,构建并提升金融风险监测与... 详细信息

当前,我国金融业数字化转型从多点突破进入深化和高质量发展的新阶段,需要协调包括管理部门、企业、个人在内的多元主体形成协同共治机制;针对数字化转型背景下产生的新型、复杂、潜在危害突出的金融风险问题,构建并提升金融风险监测与预警能力以切实保障金融安全,是金融业需要关注和亟待解决的核心课题。本文通过文献调研、理论分析等方式,分析了我国金融业数字化转型的进展、新型金融风险的内涵及特征,梳理了国内外主流的金融风险监测与预警技术进展,研判了金融风险监测与预警体系面临的风险表征识别、风险传导追踪、风险推理评估等方面的突出问题,提出了数字化转型背景下金融风险监测与预警体系的总体框架、创新研究方法、提升路径。研究发现,数字化转型背景下金融风险具有更新迭代更快、风险频次更高、隐蔽性更强等新特征,现有金融风险监测与预警技术在应对新型金融风险时存在诸多不足,面临着风险难表征、难追踪、难评估等诸多挑战。为此建议,加强行业协同、构建金融数据跨业共享标准,总结历史经验、形成金融风险知识表征范式与金融风险跨业传导机制,深化人工智能应用、构建金融风险监测与预警大模型,以提高我国金融风险防范水平、维护国家金融安全。

关键词：金融业数字化转型金融风险监测预警机器学习数据挖掘

Role of 5-hydroxytryptamine type 3 receptors in the regulation of anxiety reactions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 23-37页

作者： yinan DU Zhiwei LI Yukui ZHAO jing HAN Weiping HU Zhiqiang LIU MOE Key Laboratory of Modern Teaching Technology Shaanxi Normal UniversityXi’an710062China

5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor *** the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety *** have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and *** provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)***,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R ***,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.

关键词： 5-Hydroxytryptamine type 3 receptor(5-HT_(3)R) Anxiety Medial prefrontal cortex Amygdala Hippocampus Periaqueductal gray

A Coding-Based Incremental Traceback Scheme against DDoS Attacks in MANET

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Communications and Network 2013年第3期5卷 478-484页

作者： yinan jing Qiang Jiang Xiaochun Xiao Xueping Wang School of Computer Science Fudan University Shanghai China

Due to constrained resources, DDoS attack is one of the biggest threats to MANET. IP traceback technique is useful to defend against such type of attacks, since it can identify the attack sources. Several types of traceback schemes have been proposed for wired networks. Among all the existing schemes, probabilistic packet marking (PPM) scheme might be the most promising scheme for MANET. However its performance in MANET is not as good as that in Internet. In this paper, a new scheme based on the codingtechnique (CT) is proposed for traceback in MANET. Furthermore, a new idea of Incremental traceback is raised to cope with the situation of incremental attack (ICT). We present the protocol design and conduct theoretical analysis of this scheme. Additionally, we conduct experiments to compare it with the traditional PPM scheme. The experimental results show that the new coding-based traceback scheme outperforms the PPM scheme in MANET.

关键词： IP Traceback MANET Coding DDoS Incremental Traceback

文化转型视角下英国学校价值教育的变革:取向与形式

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外国教育研究 2024年第6期51卷 70-83页

作者：付轶男马静东北师范大学国际与比较教育研究院吉林长春130024

文化转型研究表明,当一个国家的经济增长使生存安全得到保障,就会引发文化转型,从生存价值观转向自我表现价值观。20世纪70年代英国进入了文化转型阶段,英国学校价值教育开始转向“后物质主义”,其取向与形式出现三种与文化转型相应的... 详细信息

文化转型研究表明,当一个国家的经济增长使生存安全得到保障,就会引发文化转型,从生存价值观转向自我表现价值观。20世纪70年代英国进入了文化转型阶段,英国学校价值教育开始转向“后物质主义”,其取向与形式出现三种与文化转型相应的变革趋势:从一元化到多元化;从追求生存安全到增进幸福感;从培养消极公民到培养积极公民。在文化转型的视角下观察英国学校价值教育的变革有助于理解文化转型与价值教育变迁之间的关系和价值生成条件,这对于文化转型已经初见端倪的中国来说,可以在文化转型下的学校价值教育变革策略、提高价值教育有效性等方面提供参考。

关键词：英国学校价值教育变革文化转型

Ni-Cu bimetallic alloy anchored on nitrogen-doped carbon nanotubes for CO_(2)-to-CH_(4) electrochemical conversion

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Nano Research 2024年第8期17卷 6922-6930页

作者： jing Li Chuanyong jing Jin Wang School of Environment Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality SafeguardBeijing Jiaotong UniversityBeijing 100044China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Tangshan Research Institute Beijing Jiaotong UniversityTangshan 063000China

Electrocatalytic CO_(2) reduction to CH_(4) remains challenging due to multi-electron transfer and intermediates ***,we synthesized electrocatalysts by growing Ni-Cu alloy structure on nitrogen-doped carbon nanotubes(NixCuy-NCNT)for electrocatalytic CO_(2) reduction reaction(CO_(2)RR)via hydrothermal method followed by *** optimized Ni_(1)Cu_(1)-NCNT demonstrated a superior CO_(2)RR performance,achieving 99.7%FECH_(4)(FE=Faradaic efficiency)and 11.54 mA·cm^(−2) current density at−1.2 V *** hydrogen electrode(RHE),which outperformed single metal *** outstanding performance was due to the electrons transferred from Cu to Ni and Ni-Cu alloy shifted the d-band center toward the Fermi level,which was more conducive to the intermediate *** situ electrochemical attenuated total reflection(EC-ATR)and density functional theory(DFT)calculations revealed the appearance of *CHO intermediate and the pathway during the CO_(2)RR *** design of the bimetallic electrocatalyst in this study provides a new perspective for the highly selective reduction of CO_(2).

关键词： electrocatalytic CO_(2) reduction Ni-Cu alloy nitrogen-doped carbon nanotube(NCNT) electrochemical attenuated total reflection(EC-ATR) density functional theory(DFT)calculations

An uncertainty investigation for liner impedance eduction methods

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Chinese Journal of Aeronautics 2024年第3期37卷 49-59页

作者： Weihao SHI Xiaodong jing School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Impedance eduction methods have been developed for decades to meet the increasing need for high-quality impedance data in the design and optimization of acoustic *** this end,it is important to fully investigate the uncertainty problem,to which only limited attention has been devoted so *** paper considers the possibility of acoustically-induced structural vibration as a nonnegligible uncertainty or error source in impedance eduction *** the frequency moves away from the resonant frequency,with the increase in the value of cavity reactance,the acoustic particle velocity inside liner orifices possibly decreases to the extent comparable to the vibration velocity of liner facing ***,the acoustically-induced vibration,although generally being weak except at the inherent structural frequencies,may considerably affect the impedance eduction results near the anti-resonant frequency where the liner has poor *** demonstrate the effect of structural vibration,the vibration velocity of liner facing sheet is estimated from the experimentally educed admittance of the liner samples whose orifices are sealed with ***,a three-dimensional numerical model is set up,in which normal particle velocity is introduced over the solid portion of liner facing sheet to imitate structural vibration,rather than directly solving the acoustic-structural coupling *** shown by the results,the vibration of liner facing sheet,whose velocity is as small as estimated by the experiment,can result in anomalous deviation of the educed impedance from the impedance model near the anti-resonant *** trend that the anomalous deviation varies with frequency is numerically captured.

关键词： Impedance eduction Uncertainty analysis Acoustically-induced structural vibration Anti-resonant frequency Perforated liner

A review on numerical studies of airflow dynamics and particle deposition in human respiratory system Author links open overlay panel

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Particuology 2024年第8期91卷 351-377页

作者： Hao jing Xinguang Cui School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China

Accurate assessment and prediction of airflow dynamics and particle deposition in the human respiratory tract are essential for human health,involving inhaled drugs for treating various diseases and toxic particles that can cause *** intricate process involves complex multiphase flow with distinct respiratory *** fluid dynamics(CFD)acts as a bridge,overcoming the limitations of in vivo and in vitro experiments and providing a means to fully comprehend and reveal the fundamental mechanisms of respiratory flow and particle behavior on a microscopic *** paper provides a comprehensive overview and concise summary of recent advancements in the numerical simulation of airflow and particle deposition in the human respiratory ***,it summarizes the transition of respiratory tract models from segmented models to emerging physiological characteristic models and whole-lung airway models,and the latest developments on the effects of key factors such as geometric variations,respiratory patterns,and particle physical/chemical properties on respiratory flow and particle deposition.A notable focus of this review is on emerging physiological characteristics models and their associated complex airflow and particle dynamics inside *** paper concludes with recommendations for future research to further advance the development of this field.

关键词： Airflow dynamics Particle deposition Human respiratory system Numerical modeling

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： TIAN jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression