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基于半监督学习的邮件伪装攻击检测方法

数据与计算发展前沿 2024年第2期6卷 56-66页

作者：李畅龙春赵静杨悦王跃达潘庆峰叶晓虎吴铁军唐宁中国科学院计算机网络信息中心北京100083 中国科学院大学北京100039 论客科技(广州)有限公司广东广州511400 绿盟科技集团股份有限公司北京100089 东南大学网络空间安全学院江苏南京211189 北京天融信网络安全技术有限公司北京100193

【目的】伪装攻击是电子邮件系统中一种典型攻击,通过非法获取用户真实的身份验证凭证来访问未经授权的服务,造成重大损害。由于邮件使用场景复杂,数据分布不均匀,能获得的标记异常数据数量有限导致邮件系统伪装攻击异常检测困难。【方... 详细信息

【目的】伪装攻击是电子邮件系统中一种典型攻击,通过非法获取用户真实的身份验证凭证来访问未经授权的服务,造成重大损害。由于邮件使用场景复杂,数据分布不均匀,能获得的标记异常数据数量有限导致邮件系统伪装攻击异常检测困难。【方法】针对上述问题,本文提出了一种基于规则的自训练自动编码器异常检测框架。首先,针对SMTP邮件协议的日志数据,对其应用场景进行分析和分类,并提出粗粒度的标签修正规则。其次,利用自动编码器通过自训练进行迭代检测,通过规则对每次检测结果进行修正。最后,使用核密度估计方法找到合适的阈值减少误报率。【结果】本文使用了6,736个真实企业邮箱账户连续3个月的数据,检测到7个异常账号和12个异常IP地址,与企业安全运营中心(SOC)和3种先进算法比较,效果达到最优。本文方法所检测到的异常账号数量比SOC多75%,同时误报账号减少81.3%。

关键词：半监督学习自训练自动编码器伪装攻击邮件协议

Acute histopathological responses and long-term behavioral outcomes in mice with graded controlled cortical impact injury

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Neural Regeneration Research 2019年第6期14卷 997-1003页

作者： Si-Yi Xu Min Liu Yang Gao Yang Cao Jin-Gang Bao Ying-Ying Lin Yong Wang Qi-Zhong Luo Ji-Yao Jiang chun-long Zhong Department of Neurosurgery Ren Ji HospitalSchool of MedicineShanghai Jiao Tong University Department of Neurosurgery Shanghai East HospitalTongji University School of Medicine

While animal models of controlled cortical impact often display short-term motor dysfunction after injury, histological examinations do not show severe cortical damage. Thus, this model requires further improvement. Mice were subjected to injury at three severities using a Pin-Point^(TM)-controlled cortical impact device to establish secondary brain injury mouse models. Twenty-four hours after injury, hematoxylin-eosin staining, Fluoro-Jade B histofluorescence, and immunohistochemistry were performed for brain slices. Compared to the uninjured side, we observed differences of histopathological findings, neuronal degeneration, and glial cell number in the CA2 and CA3 regions of the hippocampus on the injured side. The Morris water maze task and beam-walking test verified long-term(14–28 days) spatial learning/memory and motor balance. To conclude, the histopathological responses were positively correlated with the degree of damage,as were the long-term behavioral manifestations after controlled cortical impact. All animal procedures were approved by the Institutional Animal Care and Use Committee at Shanghai Jiao Tong University School of Medicine.

关键词： nerve regeneration traumatic brain injury controlled cortical impact histopathology behavioral manifestations neural regeneration

Honoring a legend: Celebrating the life and legacy of Professor Heng Li

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Plant Diversity 2023年第3期45卷 239-240页

作者： Hui-Jun Guo Jin-Ling Huang Yun-Heng Ji Rong Li chun-Lin long Qin-Er Yang Yong-Ping Yang Ting-Shuang Yi National Plateau Wetlands Research Center Southwest Forestry UniversityKunming 650224YunnanChina Department of Biology East Carolina UniversityGreenville 27858NCUSA CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Key Laboratory of Ecology and Environment in Minority Areas(Minzu University of China) National Ethnic Affairs CommissionBeijing 100081China College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China CAS Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650GuangdongChina CAS Key Laboratory of Tropical Plant Resources and Sustainable Use Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesXishuangbanna 666303YunnanChina Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina

Professor Heng Li(李恒,March 9,1929-January 12,2023)was a legendary plant taxonomist and phytogeographer at the Kunming Institute of Botany,Chinese Academy of Sciences(Fig.1).She made important contributions to our understanding of China's flora,including the biodiversity and biogeography of Dulong Valley and the Gaoligong Mountains,as well as the vegetation of plateau lakes and wetlands in Southwest *** Heng Li received her Bachelor's degree in Russian from Beijing Foreign Studies University in 1956 and immediately joined the Institute of Geography(now Institute of Geographic Sciences and Natural Resources Research),Chinese Academy of Sciences,as a Russian *** 1961,Prof.

关键词： translator plateau Hen

Peptoid-based hierarchically-structured biomimetic nanomaterials: Synthesis, characterization and applications

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Science China Materials 2020年第7期63卷 1099-1112页

作者： Jianli Liu Bin Cai Lifeng Cui chun-long Chen School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China Physical Sciences Division Physical and Computational Sciences DirectoratePacific Northwest National LaboratoryRichland WA 99352USA

Peptoids(or poly-N-substituted glycines)are a promising class of bioinspired sequence-defined polymers due to their highly efficient synthesis,high chemical stability,enzyme hydrolysis resistance,and *** tuning the side chain chemistry of peptoids,it allows for precise control over sequences and achieving a large side-chain *** to these unique features,in the last several years,many amphiphilic peptoids were designed as highly tunable building blocks for the preparation of biomimetic nanomaterials with well-defined hierarchical structures and desired ***,we provide an overview of the recent achievements in this area by dividing them into the following three ***,mica-and silica-templated peptoid selfassembly are *** presence of inorganic substrates provides the guarantee of investigating their selfassembly mechanisms and interactions between peptoids and substrates using nanoscale characterization techniques,particularly in situ atomic force microscopy(AFM)and AFMbased dynamic force spectroscopy(AFM-DFS).Second,solution-phase self-assembly of peptoids into nanotubes and nanosheets is presented,as well as their self-repair ***,the applications of peptoid-based nanomaterials are outlined,including the construction of catalytic nanomaterials as a template and cytosolic delivery as cargoes.

关键词： peptoid self-assembly biomimetic nanomaterial nanoscale characterization assembly mechanism

Two new lignans from Dipteronia dyeriana

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Chinese Chemical Letters 2008年第10期19卷 1215-1217页

作者： Rong Guo Min Luo chun Lin long Ma Lin Li Zhi Qin Ouyang Yi Ping Zhou Yue Hu Wang Xing Yu Li Ya Na Shi Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Yunnan Agricultural University Kunming 650201 China Yunnan Laboratory of Pharmacology for Natural Products Kunming Medical College Kunming 650031 China Yunnan Introduction ＆ Propagation Center for Rare ＆ Endangered Plants Kunming 650032 China

A new sesquilignan, 7＇,8＇-didehydroherpetotriol （1）, and a new lignan glycoside, （＋）-isolariciresinol-9＇-O-α-L-rhamnopyra- nosy1-（1→6）-[3-D-glucopyranoside （2）, were isolated from the branches of Dipteronia dyeriana. Their structures were elucidated by spectroscopic methods and chemical evidence. Compound 1 possessed inhibitory activity against human leukaemia K562 cells with an IC50 value of 39 μmol/L.

关键词： Aceraceae Dipteronia dyeriana Lignans Didehydroherpetotriol Leukaemia

认知分歧与内群偏私:公共政策绩效损失问题研究

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兰州大学学报（社会科学版） 2016年第2期44卷 61-67页

作者：霍春龙兰州大学管理学院甘肃兰州730000

改革开放30多年以来,公共政策绩效损失现象日渐增多。试图从公共政策绩效生产过程角度来回答公共政策产出与公共价值之间的差距问题。运用社会心理学以及PV-GPG理论阐释了公共政策绩效生产过程中的群体合作与群体冲突行为产生的过程,从... 详细信息

改革开放30多年以来,公共政策绩效损失现象日渐增多。试图从公共政策绩效生产过程角度来回答公共政策产出与公共价值之间的差距问题。运用社会心理学以及PV-GPG理论阐释了公共政策绩效生产过程中的群体合作与群体冲突行为产生的过程,从中分析公共政策绩效损失产生的逻辑起点、原因以及影响要素。研究发现:公共政策绩效损失的逻辑起点是政策利益主体的认知分歧;公共政策绩效损失产生的原因是,公共政策绩效生产过程中政策价值目标的相对稳定性与利益群体价值分散性的矛盾;影响公共政策绩效损失的主要因素有认知场所、社会观念以及政策包容性。最后提出了减少公共政策绩效损失的对策建议。

关键词：公共政策绩效损失自我范畴化认知分歧内群偏私共享现实

认知分歧与共享现实:公共政策绩效损失是如何产生的?

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兰州大学学报（社会科学版） 2017年第3期45卷 67-75页

作者：霍春龙兰州大学管理学院甘肃兰州730000

公共政策绩效损失问题是一个亟待解决的难题。运用案例研究方法,将"什邡决策困局"作为研究对象,回答了"什邡钼铜项目"决策绩效损失产生的过程、原因与内在机制等理论问题。研究首先梳理了"什邡钼铜项目"决策绩效损失的产生过程,即由认... 详细信息

公共政策绩效损失问题是一个亟待解决的难题。运用案例研究方法,将"什邡决策困局"作为研究对象,回答了"什邡钼铜项目"决策绩效损失产生的过程、原因与内在机制等理论问题。研究首先梳理了"什邡钼铜项目"决策绩效损失的产生过程,即由认知分歧一利益分歧—街头抗议—绩效损失的过程。在此基础上,归纳了关于公共决策绩效损失的理论:界定了公共政策绩效损失的涵义并说明了其研究价值;发现公共价值建构不足是导致政策绩效损失的根本原因;发现认知分歧、共享现实等社会心理因素是公共政策绩效损失产生的内在机制性因素;发现绩效领导力以及合作生产理念不足是公共政策绩效损失的主要原因;认为政府必须重视和应对社会认知场所的深刻变革。

关键词：政策绩效损失认知分歧共享现实什邡事件

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui Dong chun-Yin Zhou Zi-long Zhao Dong-Xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Explicit and Exact Solutions to N-Order Schrdinger System via an Extended Mapping Approach

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Communications in Theoretical Physics 2006年第3期 483-486页

作者： ZHU Hai-Ping ZHENG chun-long FANG Jian-Ping Department of Physics,Zhejiang Lishui University,Lishui 323000,ChinaZHENG chun-long Shanghai Institute of Applied Mathematics and Mechanics,Shanghai University,Shanghai 200072,China Department of Physics，Zhejiang Lishui University，Lishui 323000，China Department of Physics，Zhejiang Lishui University，Lishui 323000，China Shanghai Institute of Applied Mathematics and Mechanics，Shanghai University，Shanghai 200072，China

In this paper,we extend the mapping approach to the N-order Schr(o|¨)dinger *** terms of theextended mapping approach,new families of variable separation solutions with some arbitrary functions are derived.

关键词： extended mapping approach Schr(o|¨)dinger equation exact solution