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融合威胁情报与知识图谱的网络攻击溯源方法

情报杂志 2024年第8期43卷 72-83,91页

作者：张玉臣孙澄姜迎畅马军强胡浩战略支援部队信息工程大学郑州450001

[研究目的]攻击溯源是网络空间安全保障的重要组成部分,面对网络空间数据海量、异质多元、结构松散等特点,亟需大数据分析与人工智能相结合,有效识别敌手攻击威胁,溯源攻击链和背后的攻击组织,并实施针对性防御。[研究方法]针对攻击威... 详细信息

[研究目的]攻击溯源是网络空间安全保障的重要组成部分,面对网络空间数据海量、异质多元、结构松散等特点,亟需大数据分析与人工智能相结合,有效识别敌手攻击威胁,溯源攻击链和背后的攻击组织,并实施针对性防御。[研究方法]针对攻击威胁特征识别难的问题,提出了知识图谱驱动的网络攻击溯源方法,以脆弱性利用动作为核心构建攻击事件框架,并以事件为单位实施告警关联,重构攻击场景。在此基础上,利用威胁指纹知识图谱,整合已公开的威胁情报知识,并抽取攻击场景中的威胁特征作为指纹,分析两者相似性,溯源攻击者。[研究结论]实验结果表明,该方法能够利用攻击事件框架充实攻击行为的上下文信息,并基于知识图谱有效溯源攻击者,从而利用攻击者已有的威胁情报,增强高级可持续攻击威胁特征识别的全面性。

关键词：威胁情报威胁指纹知识图谱攻击溯源威胁识别场景重构

基于随机博弈与A3C深度强化学习的网络防御策略优选

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指挥与控制学报 2024年第1期10卷 47-58页

作者：胡浩赵昌军刘璟宋昱欣姜迎畅张玉臣战略支援部队信息工程大学郑州450001

网络资源的有限性和攻防对抗的动态性导致最优防御策略难以选取,将深度强化学习引入攻防随机博弈建模领域,通过构建网络攻防actor策略网络和critic价值网络,结合随机博弈模型构建了网络攻防博弈决策模型总体结构,在此基础上引入异步优... 详细信息

网络资源的有限性和攻防对抗的动态性导致最优防御策略难以选取,将深度强化学习引入攻防随机博弈建模领域,通过构建网络攻防actor策略网络和critic价值网络,结合随机博弈模型构建了网络攻防博弈决策模型总体结构,在此基础上引入异步优势演员评论家算法(asynchronous advantage actor-critic,A3C)智能体学习框架设计了防御策略选取算法;针对现有方法未考虑攻击方群体间的共谋攻击,引入群智能体性格特征,建立合作系数μ来刻画攻击者之间的合作对攻防策略收益的影响,进而得出对防御策略选取的影响,构建的博弈决策模型更符合攻防实际情况。实验结果表明,该方法的策略求解速度要优于现有方法,同时由于考虑了攻击合作关系,能够用于分析攻击者群体间合作关系对防御者决策的影响,防御策略选取更有针对性,期望防御收益更高。

关键词：网络攻防最优防御决策随机博弈多智能体 A3C算法

Latent Heat Enhancement of Stearic Acid nanoparticle Capsulated with Sillica

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Latent Heat Enhancement of Stearic Acid nanoparticle Capsula...

中国颗粒学会超微颗粒专委会2013年年会暨第八届海峡两岸超微颗粒学术研讨会

作者： yingchang jiang Qi Ji Shudong Zhang Zhenyang Wang Institute of Intelligent Machines Chinese Academy of Sciences School of Physics and Engineering Zhengzhou University

In this work,SA@SiO nanocapsules(NCs) were designed and fabricated to research its phase change *** by the selected sillica nanoshells,Latent heat of stearic acid(SA) could be increased up to 374.2 kJ/kg,about 36.9%more than that of pure *** can be attributed to the high superimposed stress from curvature effect inside SiO nanoshells,which would strengthen hydrogen bonds of SA encapsulated in the sillica

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基于注意力机制的海上小目标重识别方法

机电工程技术 2022年第7期51卷 100-103页

作者：崔海朋姜英昌青岛杰瑞工控技术有限公司山东青岛266000

在海上由于涉及到目标的遮挡、背景及照明等的巨大变化,小目标重识别是一项极具挑战性的计算机视觉任务。针对传统小目标识别算法泛化性差,在目标重识别中特征提取不够充分有效的问题,提出一种基于通道和空间注意力机制的目标重识别方... 详细信息

在海上由于涉及到目标的遮挡、背景及照明等的巨大变化,小目标重识别是一项极具挑战性的计算机视觉任务。针对传统小目标识别算法泛化性差,在目标重识别中特征提取不够充分有效的问题,提出一种基于通道和空间注意力机制的目标重识别方法。首先,通过将CBAM机制嵌入到重识别模型的骨干网中,通过引入通道注意力机制和空间注意力机制,反馈了更加关键的特征信息。针对骨干输出的三维特征量,为得到更有效的信息,沿垂直进行不同比例的平均分块,从而在多粒度的情况下,从全局和局部更加全面地关注图像信息,同时利用多损失函数分别优化模型,提升模型的可区分性。最后将梯度中心化算法引入Adam优化器,提升网络模型的训练速度和泛化能力,为海上小目标重识别提供了一种新的研究思路与方法。

关键词：深度学习注意力机制海上小目标梯度中心化

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沾化凹陷桩西地区沙三段-沙一段沉积相及其演化

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地质科技情报 2017年第4期36卷 73-81页

作者：张会娜操应长石世革姜珊远光辉邓涛丁坤中国石油大学(华东)地球科学与技术学院山东青岛266580 胜利油田桩西采油厂山东东营257000

沾化凹陷桩西地区沙三段-沙一段沉积时期构造复杂,沉积类型多样。在研究区17口取心井岩心观察和描述的基础上,结合地震、测井、录井等资料,对桩西地区沙三段-沙一段的扇三角洲、浊积岩和滩坝等沉积体特征及演化进行了系统分析。在沉积... 详细信息

沾化凹陷桩西地区沙三段-沙一段沉积时期构造复杂,沉积类型多样。在研究区17口取心井岩心观察和描述的基础上,结合地震、测井、录井等资料,对桩西地区沙三段-沙一段的扇三角洲、浊积岩和滩坝等沉积体特征及演化进行了系统分析。在沉积相研究的基础上,根据单因素分析多因素综合作图法,选取砂砾岩厚度、砂砾岩百分含量、碳酸盐岩厚度及生物灰岩百分含量分布等单因素,对桩西地区沙河街组不同层段的沉积相平面展布特征进行了深入研究,并探讨了其演化规律。结果表明:桩西地区沙三段沉积时期在靠近长堤断层的湖盆边缘沉积扇三角洲砂体,在湖盆中心同生断层下降盘沉积浊积岩砂体;沙二段沉积时期在靠近长堤断层的湖盆边缘沉积扇三角洲砂体,在桩西潜山周缘和研究区西北边缘处沉积互层的砂质滩坝和生物滩;沙一段沉积时期主要在靠近湖盆边缘沉积生物滩和湖相碳酸盐岩,在湖盆中心部位沉积泥岩和油泥岩。

关键词：桩西地区沙三段-沙一段沉积相沉积模式

Effect of bilobalide B on cholinergic hippocampal neurons exposed to cholesterol and apolipoprotein E4

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Neural Regeneration Research 2008年第5期3卷 469-471页

作者： Xijuan jiang Bin Lu yingchang Fan Department of Pathology Tianjin University of Traditional Chinese Medicine Tianjin 300193 China Department of Experiment and Teaching Tianjin University of Traditional Chinese Medicine Tianjin 300193 China

BACKGROUND： Extracts of ginkgo biloba leaves have been reported to improve nerve function and activity in Alzheimer＇s disease, which is associated with reduced secretion of cholinergic neurotransmitter in hippocampal neurons. OBJECTIVE： To validate the protective effect of bilobalide B against in vitro injury of cholinergic neurons of the hippocampus induced by combined cholesterol and apoE4 DESIGN, TIME AND SETTING： This randomized, controlled animal experiment was performed in the Pathology Laboratory, Tianjin University of Traditional Chinese Medicine from July 2003 to July 2006. MATERIALS： Neonatal Wistar rats, 1-day-old, both male and female, and mean body mass of 5 g were selected for this study. Cholesterol and apolipoprotein E4 （apoE4） were purchased from Sigma Company （USA）, bilobalide B was purchased from Tianjin Zhongyi Pharmaceutical Factory, batch number 20050312. METHODS： Hippocampal neurons were divided into three groups： a normal control group （routinely added media）, a model group （exposed to media containing 40 mg/L cholesterol and 30 mg/L apoE4 for 24 hours） and a bilobalide B group （exposed to media containing 160 mg/L bilobalide B for 16 hours, and then with addition of 40 mg/L cholesterol and 30 mg/L apoE4 for an additional 24 hours）. MAIN OUTCOME MEASURES： Levels of acetylcholine （ACh） and activity of acetylcholinesterase （ACHE） and choline acetyltransferase （CHAT） in hippocampal neurons were determined by microdosage hydroxylamine colorimetry, hydroxylamine colorimetry and radiological chemistry, respectively. RESULTS： The ACh level was significantly lower in the model group than that in the normal control group （P 〈 0.01）, while it was markedly higher in the bilobalide B group than in the model group （P 〈 0.05）. Activity of AChE was significantly decreased in the model group compared with the normal control group （P 〈 0.05）. However, there was no significant difference between the model group and the bilobalide B group （P 〉 0.05）. Activity o

关键词： Alzheimer's disease cholesterol apolipoprotein E4 bilobalide B acetylcholine acetylcholinesterase choline acetyltransferase

Hydrogel-based optically and mechanically manipulable broadband microwave absorber

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Nano Research 2023年第7期16卷 10175-10182页

作者： Xiqiao Chen Lin Du Guobao jiang Zhuang Wu yingchang Zou Yanhong Zou School of Electronic Information and Electrical Engineering Changsha UniversityChangsha 410022China School of Physics and Electronics Hunan UniversityChangsha 410082China

Microwave absorbers with unique optical and mechanical performance are urgent for complex electromagnetic ***,we demonstrate the mechanically flexible,optically transparent,and microwave-absorbing polyacrylamide(PAM)hydrogel,in which the polar water molecules with high polarization contribute to the efficient microwave attenuation,but the binding between water molecules and PAM will slow down the orientation polarization of polar ***,the dominated dielectric property of water molecules in PAM hydrogel determines that the molecules displacement in polymer mixture is feasible for manipulating ***,by decreasing temperature,the flexible and transparent hydrogel will switch to rigid and opaque state as the phase conversion between amorphous and polycrystal *** constructing structures with such hydrogel,the obtained absorber also exhibits the optical and mechanical switchable properties,covering the effective absorption within 5.7-18 *** work provides an effective method to fabricate optically and mechanically manipulable microwave absorbers for intelligent electromagnetic stealth systems.

关键词： microwave absorption polyacrylamide hydrogel optical properties mechanical properties

Sedimentary Characteristics and Paleoenvironment of Shale in the Wufeng-Longmaxi Formation, North Guizhou Province, and Its Shale Gas Potential

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Journal of Earth Science 2017年第6期28卷 1020-1031页

作者： Chao Liang Zaixing jiang yingchang Cao Jinchuan Zhang Ling Guo School of Geosciences China University of Petroleum Qingdao 266000 China Shandong Province Key Laboratory of Depositional Mineralization & Sedimentary Mineral Shandong University of Science and Technology Qingdao 266590China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing100083 China School of Energy Resource China University of Geosciences Beijing 100083 China Department of Geology Northwest University Xi'an 710069 China

The Paleozoic Wufeng-Longmaxi shale is one of the main horizons for shale gas exploration in Sichuan Basin. Outcrop, core and thin section observations, X-ray diffraction analysis, trace element geochemistry and other methods have been used to understand the sedimentary characteristics and identify hydrocarbon source rocks in suitable sedimentary paleoenvironments in the Wufeng-Longmaxi shale in northern Guizhou Province. The thickness of the Wufeng-Longmaxi Formation ranges from 20 to 200 m and it was mainly deposited on a deep-water shelf. The TOC content is high, up to 5.75%. The main non-organic minerals are detrital quartz and clay minerals, with a little plagioclase feldspar, potassium feldspar, calcite, dolomite and pyrite. There is also biogenic microcrystalline quartz. Six lithofacies have been identified： siliceous shale, clay shale, calcareous shale, silty shale, carbonaceous shale, and muddy siltstone. Using biological Ba, V/（V＋Ni）, TOC, V/Cr, B, Sr/Ba and other indicators, we estimate primary productivity, redox conditions and paleosalinity and show that the early stage of Wufeng-Longmaxi deposition occurred under strong anoxic conditions, high paleosalinity and yielded a high TOC content and an excellent potential shale gas source. The anoxic environment was destroyed at the late stages of Wufeng-Longmaxi deposition, the TOC content decreased, so that it is likely to be a high quality source rock. Organic pores acted as the key reservoir space in the shales, and the pores are mainly mesopose, with most pore diameters less than 20 nm. The siliceous shale has high TOC content and brittle mineral（quartz） content making it an important exploration target for shale oil and gas exploration.

关键词： Wufeng-Longmaxi shale sedimentary characteristics geochemistry paleo-environment restoration shale gas

Evolution characteristics and exploration targets of Permian clastic rock reservoirs in Bohai Bay Basin,East China

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Petroleum Exploration and Development 2023年第5期50卷 1077-1091页

作者： CAO yingchang SUN Peipei ZHOU Lihong YUAN Guanghui LIU Huimin LOU Da WU Zhiping JIN Qiang jiang Youlu National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Evaluation and Exploration Technology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China PetroChina Dagang Oilfield Company Tianjin 300280China Sinopec Shengli Oilfield Company Dongying 257001China

Based on core observation, thin section examination, fluid inclusions analysis, carbon and oxygen isotopic composition analysis, and other approaches, the structural and burial evolution histories were investigated, and the diagenetic evolution process and genetic/development models were systematically discussed of the Upper Paleozoic Permian clastic rock reservoirs in the Bohai Bay Basin, East China. The Bohai Bay Basin underwent three stages of burial and two stages of uplifting in the Upper Paleozoic. Consequently, three stages of acid dissolution generated by the thermal evolution of kerogen, and two stages of meteoric freshwater leaching occurred. Dissolution in deeply buried, nearly closed diagenetic system was associated with the precipitation of authigenic clay and quartz, leading to a limited increase in storage space. Different structural uplifting–subsidence processes of tectonic zones resulted in varying diagenetic–reservoir-forming processes of the Permian clastic reservoirs. Three genetic models of reservoirs are recognized. The Model I reservoirs with pores formed in shallow strata and buried in shallow to medium strata underwent two stages of exposure to long-term open environment and two stages of meteoric freshwater leaching to enhance pores near the surface, and were shallowly buried in the late stage, exhibiting the dominance of secondary pores and the best physical properties. The Model Ⅱ reservoirs with pores formed in shallow strata and preserved due to modification after deep burial experienced an early exposure-open to late burial-closed environment, where pore types were modified due to dissolution, exhibiting the dominance of numerous secondary solution pores in feldspar and the physical properties inferior to Model I. The Model Ⅲ reservoirs with pores formed after being regulated after multiple periods of burial and dissolution experienced a dissolution of acidic fluids of organic origin under a near-closed to closed environment, exhibiti

关键词： Bohai Bay Basin Permian clastic rock diagenetic evolution reservoir-forming mechanism secondary pore