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网络运行安全指数多维属性分类模型

计算机学报 2012年第8期35卷 1666-1674页

作者：张永铮云晓春中国科学院计算技术研究所北京100190 中国科学院信息工程研究所北京100093 信息内容安全技术国家工程实验室北京100190

安全指数作为反映和测度网络安全态势的一种核心方法,具有重要的研究意义.为度量网络信息系统在运行过程中的安全态势,文中给出了网络运行安全指标和指数的定义,提出了10个关键分类属性以及指数分类的通用概念模型ICM,该模型为具体指数... 详细信息

安全指数作为反映和测度网络安全态势的一种核心方法,具有重要的研究意义.为度量网络信息系统在运行过程中的安全态势,文中给出了网络运行安全指标和指数的定义,提出了10个关键分类属性以及指数分类的通用概念模型ICM,该模型为具体指数分类模型的构建和不同分类模型的比较提供了统一的模型方法.基于ICM模型和10维分类属性,文中同时提出了一个多维属性指数分类模型ICM M10,并通过4个典型指数的应用实例阐明了M10模型的应用过程和应用意义.应用实例分析表明,M10模型能够刻画出安全指数在10个关键属性上的本质特性,对深入研究指数特性、关系及其内在含义具有指导意义,同时,也为建构多层次安全指数体系提供了理论和技术基础.

关键词：网络安全态势安全指数指标体系分类评估

Loss of SHROOM3 affects neuroepithelial cell shape through regulating cytoskeleton proteins in cynomolgus monkey organoids

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Zoological Research 2024年第2期45卷 233-241页

作者： Peng Li Ting zhang Ruo Wu Jun-Yu zhang Yan Zhuo Shan-Gang Li Jiao-Jian Wang Wen-Ting Guo zheng-Bo Wang yong-Chang Chen State Key Laboratory of Primate Biomedical Research Institute of Primate Translational MedicineKunming University of Science and TechnologyKunmingYunnan 650500China Yunnan Key Laboratory of Primate Biomedical Research KunmingYunnan 650500China

Neural tube defects(NTDs)are severe congenital neurodevelopmental disorders arising from incomplete neural tube *** folate supplementation has been shown to mitigate the incidence of NTDs,some cases,often attributable to genetic factors,remain *** SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation;at present,however,the underlying mechanism remains *** tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural *** determine the role of SHROOM3 in early developmental morphogenesis,we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate *** of SHROOM3 resulted in shorter neuroepithelial cells and smaller *** morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins,namely fibrous actin(F-actin),myosin II,and phospho-myosin light chain(PMLC),to the apical side of the neuroepithelial ***,these defects were not rescued by folate *** sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ *** summary,we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.

关键词： Neural tube defects SHROOM3 Neuroepithelial Organoids Cynomolgus monkey

Stochastic resonance of spinor condensates in optical cavity

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 80-87页

作者： zheng-Chun Li Bixuan Fan Lu Zhou Weiping zhang School of Physics and Astronomy and Tsung-Dao Lee InstituteShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China Shanghai Branch Hefei National LaboratoryShanghai 201315China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Stochastic resonance is a phenomenon in which adding random noise to a system enhances the detection or transmission of a weak signal. It occurs when the noise interacts with the system's nonlinearity, thus improving signal-to-noise ratio and increasing sensitivity. Although parametric resonances in an atomic spinor Bose-Einstein condensate have been investigated, the question of whether one can observe stochastic resonance in such a system persists. In this study we propose a scheme for generating stochastic resonance in a cavity-spinor Bose-Einstein condensate coupling system. We demonstrate stochastic resonance through numerical calculations using the mean-field theory and truncated Wigner approximation methods. Furthermore, the characteristics of the system's response to noise and periodic signals are studied in detail. This study unravels a new scheme for observing stochastic resonance via linking atomic many-body physics with cavity quantum electrodynamics.

关键词： spinor condensate stochastic resonance optical cavity

ASYMPTOTIC THEORY FOR THE CIRCUIT ENVELOPE ANALYSIS

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Journal of Computational Mathematics 2024年第4期42卷 955-978页

作者： Chunxiong zheng Xianwei Wen Jinyu zhang Zhenya Zhou College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830046China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Empyrean Software Empyrean Technology Co.Ltd.Beijing 100102China

Asymptotic theory for the circuit envelope analysis is developed in this paper.A typical feature of circuit envelope analysis is the existence of two significantly distinct timescales:one is the fast timescale of carrier wave,and the other is the slow timescale of modulation *** first perform pro forma asymptotic analysis for both the driven and autonomous *** resorting to the Floquet theory of periodic operators,we make a rigorous justification for first-order asymptotic *** turns out that these asymptotic results are valid at least on the slow *** speed up the computation of asymptotic approximations,we propose a periodization technique,which renders the possibility of utilizing the NUFFT *** experiments are presented,and the results validate the theoretical findings.

关键词： Asymptotic analysis Circuit envelope analysis Floquet theory Singularly perturbed problem

Assessing the Performance of CMIP6 Models in Simulating Droughts across Global Drylands

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Advances in Atmospheric Sciences 2024年第2期41卷 193-208页

作者： Xiaojing YU Lixia zhang Tianjun ZHOU Jianghua zheng LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China College of Geography&Remote Sensing Sciences Xinjiang UniversityUrumqi 830046China

Both the attribution of historical change and future projections of droughts rely heavily on climate modeling. However,reasonable drought simulations have remained a challenge, and the related performances of the current state-of-the-art Coupled Model Intercomparison Project phase 6(CMIP6) models remain unknown. Here, both the strengths and weaknesses of CMIP6 models in simulating droughts and corresponding hydrothermal conditions in drylands are *** the general patterns of simulated meteorological elements in drylands resemble the observations, the annual precipitation is overestimated by ~33%(with a model spread of 2.3%–77.2%), along with an underestimation of potential evapotranspiration(PET) by ~32%(17.5%–47.2%). The water deficit condition, measured by the difference between precipitation and PET, is 50%(29.1%–71.7%) weaker than observations. The CMIP6 models show weaknesses in capturing the climate mean drought characteristics in drylands, particularly with the occurrence and duration largely underestimated in the hyperarid Afro-Asian areas. Nonetheless, the drought-associated meteorological anomalies, including reduced precipitation, warmer temperatures, higher evaporative demand, and increased water deficit conditions, are reasonably reproduced. The simulated magnitude of precipitation(water deficit) associated with dryland droughts is overestimated by 28%(24%) compared to observations. The observed increasing trends in drought fractional area,occurrence, and corresponding meteorological anomalies during 1980–2014 are reasonably reproduced. Still, the increase in drought characteristics, associated precipitation and water deficit are obviously underestimated after the late 1990s,especially for mild and moderate droughts, indicative of a weaker response of dryland drought changes to global warming in CMIP6 models. Our results suggest that it is imperative to employ bias correction approaches in drought-related studies over drylands by using CMIP6 o

关键词： droughts hydrothermal conditions drylands CMIP6 model evaluation

Three-dimensional reconstruction of precession warhead based on multi-view micro-Doppler analysis

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Journal of Systems Engineering and Electronics 2024年第3期35卷 541-548页

作者： zhang Rongzheng WANG yong MAO Jian School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Laboratory of Pinghu Pinghu 314200China

The warhead of a ballistic missile may precess due to lateral moments during release. The resulting micro-Doppler effect is determined by parameters such as the target's motion state and size. A three-dimensional reconstruction method for the precession warhead via the micro-Doppler analysis and inverse Radon transform(IRT) is proposed in this paper. The precession parameters are extracted by the micro-Doppler analysis from three radars, and the IRT is used to estimate the size of targe. The scatterers of the target can be reconstructed based on the above parameters. Simulation experimental results illustrate the effectiveness of the proposed method in this paper.

关键词： time-frequency analysis inverse Radon transform(IRT) precession warhead

Detection method of forward-scatter signal based on Rényi entropy

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Journal of Systems Engineering and Electronics 2024年第4期35卷 865-873页

作者： zheng Yuqing AI Xiaofeng YANG yong ZHAO Feng XIAO Shunping State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System National University of Defense TechnologyChangsha 410073China

The application scope of the forward scatter radar(FSR)based on the Global Navigation Satellite System(GNSS)can be expanded by improving the detection ***,the forward-scatter signal model when the target crosses the baseline is ***,the detection method of the for-ward-scatter signal based on the Rényi entropy of time-fre-quency distribution is proposed and the detection performance with different time-frequency distributions is ***-tion results show that the method based on the smooth pseudo Wigner-Ville distribution(SPWVD)can achieve the best ***,combined with the geometry of FSR,the influence on detection performance of the relative distance between the target and the baseline is ***,the proposed method is validated by the anechoic chamber measurements and the results show that the detection ability has a 10 dB improvement compared with the common constant false alarm rate(CFAR)detection.

关键词： forward scatter radar(FSR) Global Navigation Satellite System(GNSS) time-frequency distribution Rényi entropy signal detection

B cell development and antibody responses in human immune system mice:current status and future perspective

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Science China(Life Sciences) 2024年第4期67卷 645-652页

作者： Tao zhang Wentao Liu yong-Guang Yang Key Laboratory of Organ Regeneration&Transplantation of the Ministry of Education The First Hospital of Jilin UniversityChangchun 130061China National-Local Joint Engineering Laboratory of Animal Models for Human Diseases Jilin UniversityChangchun 130061China International Center of Future Science Jilin UniversityChangchun 130061China

Humanized immune system(HIS)mice have been developed and used as a small surrogate model to study human immune function under normal or disease *** variations are found between models,most HIS mice show robust human T cell ***,there has been unsuccessful in constructing HIS mice that produce high-affinity human antibodies,primarily due to defects in terminal B cell differentiation,antibody affinity maturation,and development of primary follicles and germinal *** this review,we elaborate on the current knowledge about and previous attempts to improve human B cell development in HIS mice,and propose a potential strategy for constructing HIS mice with improved humoral immunity by transplantation of human follicular dendritic cells(FDCs)to facilitate the development of secondary follicles.

关键词： humanized immune system mouse humoral immunity germinal center B cell follicular dendritic cell

A survey on federated learning:a perspective from multi-party computation

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Frontiers of Computer Science 2024年第1期18卷 93-103页

作者： Fengxia LIU Zhiming zheng Yexuan SHI yongxin TONG Yi zhang Institute of Artificial Intelligence and Key Laboratory of Mathematics Informatics Behavioral Semantics Beihang UniversityBeijing 100191China State Key Laboratory of Software Development Environment and Advanced Innovation Center for Future Blockchain and Privacy Computing Beihang UniversityBeijing 100191China Pengcheng Laboratory Shenzhen 518055China Zhongguancun Laboratory Beijing 100190China Institute for Mathematical Sciences and Engineering Research Center of Financial Computing and Digital Engineering Renmin University of ChinaBeijing 100872China

Federated learning is a promising learning paradigm that allows collaborative training of models across multiple data owners without sharing their raw *** enhance privacy in federated learning,multi-party computation can be leveraged for secure communication and computation during model *** survey provides a comprehensive review on how to integrate mainstream multi-party computation techniques into diverse federated learning setups for guaranteed privacy,as well as the corresponding optimization techniques to improve model accuracy and training *** also pinpoint future directions to deploy federated learning to a wider range of applications.

关键词： sfederated learning multi-party ycomputation privacy-preserving data mining distributed learning