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Preventing Hardware Trojans in Switch Chip Based on Payload Decoupling

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China Communications 2021年第8期18卷 96-108页

作者： Ke Song Binghao Yan xiangyu li Qinrang liu ling OuYang Information Engineering University Zhengzhou 450002China Tsinghua University Beijing 100084China

Hardware Trojans in integrated circuit chips have the characteristics of being covert,destructive,and difficult to protect,which have seriously endangered the security of the chips themselves and the information systems to which they belong.Existing solutions generally rely on passive detection techniques.In this paper,a hardware Trojans active defense mechanism is designed for network switching chips based on the principle of encryption algorithm.By encoding the data entering the chip,the argot hidden in the data cannot trigger the hardware Trojans that may exist in the chip,so that the chip can work normally even if it is implanted with a hardware Trojans.The proposed method is proved to be effective in preventing hardware Trojans with different trigger characteristics by simulation tests and practical tests on our secure switching chip.

关键词： network switching chip active defense hardware trojan payload decoupling

Near-Earth Asteroid Surveillance Constellation in the Sun-Venus Three-Body System

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Space(Science & Technology) 2022年第1期2022卷 441-461页

作者： Xingyu Zhou xiangyu li Zhuoxi Huo linzhi Meng Jiangchuan Huang School of Aerospace Engineering Beijing Institute of TechnologyBeijingChina Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijingChina Beijing Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijingChina

The threat of potential hazardous near-Earth asteroid(PHA)impact on Earth is increasingly attracting public attention.Monitoring and early warning of those PHAs are the premise of planetary defense.In this paper,we proposed a novel concept of surveillance constellation of heterogeneous wide-field near-Earth asteroid(NEA)surveyors(CROWN),in which six spacebased surveyors are loosely deployed in Venus-like orbits to detect the NEAs along the direction of the sunlight.First,the concept and overall design of the NEA surveillance constellation are discussed.Second,the transfer and deployment trajectory of the surveyors are investigated based on the Sun-Venus three-body system.The Sun-Venus libration orbit is taken as the parking orbit,and its stable invariant manifolds are used to reduce the deployment fuel consumption.Next,the detection performance of the CROWN was evaluated considering constraints of apparent visual magnitude and field of view.The NEA orbit determination(OD)using the CROWN was studied and verified.Simulation results show that the CROWN can be deployed with a total velocity increment of approximately 300 m/s.During the 5 years of observation,99.8%of PHAs can be detected and the OD precision is better than a single-surveyor system.This paper can provide a reference for the construction of future asteroid defense system.

关键词： Earth system planetary

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针对侵爆弹的毁伤效能评估方法

兵器装备工程学报 2024年第1期45卷 159-165页

作者：彭永卢芳云李翔宇国防科技大学理学院长沙410073

基于侵爆弹毁伤特征,提出针对侵爆弹的毁伤效能评估通用方法,建立了评估模型和计算流程,并以侵爆弹打击机库为例,整合并提出了相关算法,开发了软件工具,进行了毁伤效能评估案例分析。案例分析中,研究对比了侵彻速度、入射角度、目标尺... 详细信息

基于侵爆弹毁伤特征,提出针对侵爆弹的毁伤效能评估通用方法,建立了评估模型和计算流程,并以侵爆弹打击机库为例,整合并提出了相关算法,开发了软件工具,进行了毁伤效能评估案例分析。案例分析中,研究对比了侵彻速度、入射角度、目标尺寸、投射精度等因素的影响,表明了弹体威力参数以及目标参数与毁伤结果间的关系。提出的方法较为明确地给出了毁伤效能评估的内涵定义、评估内容、评估技术要点,对于侵爆弹打击其他坚固目标的毁伤效能评估具有较强的指导意义和参考价值。

关键词：侵彻爆炸毁伤效能评估掩蔽库

适用于直流保护的数学形态学降噪与噪声干扰识别方法

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电力系统保护与控制 2024年第13期52卷 136-148页

作者：薛士敏张君婷李博通李翔宇智能电网教育部重点实验室(天津大学) 天津300072

柔性直流输电系统是调节我国能源分布不均问题的重要手段,直流保护是保证柔直系统安全的重要技术。现有工程中多采用行波保护作为主保护,然而行波保护存在易受噪声影响、故障波头不易捕捉等问题,制约了其广泛应用。针对上述问题,提出数... 详细信息

柔性直流输电系统是调节我国能源分布不均问题的重要手段,直流保护是保证柔直系统安全的重要技术。现有工程中多采用行波保护作为主保护,然而行波保护存在易受噪声影响、故障波头不易捕捉等问题,制约了其广泛应用。针对上述问题,提出数学形态学降噪与噪声干扰识别方法,并根据直流保护采样信号特点进行参数设计,用于直流保护采样信号降噪和噪声干扰的识别。首先,确定基于自适应多尺度形态滤波的直流信号降噪方法,并设计结构元素长度和形态学滤波器类型、自适应多尺度形态滤波器的滤波器阶数和步长。其次,确定基于形态学梯度变换的噪声干扰识别方法,并设计形态学梯度变换的阈值。接着,从不同角度对形态学降噪方法与现有典型信号处理方法的滤波效果进行对比分析。最后,对形态学降噪与噪声干扰识别方法和保护的配合效果进行验证。形态学降噪与噪声干扰识别方法所需采样频率较低,运算量适中,滤波效果好,对直流保护适用性好。

关键词：行波保护自适应多尺度形态滤波噪声干扰识别形态学梯度故障波头捕捉

Catalytic fast pyrolysis of Kraft lignin with HZSM-5 zeolite for producing aromatic hydrocarbons

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Frontiers of Environmental Science & Engineering 2012年第3期6卷 295-303页

作者： xiangyu li Lu SU Yujue WANG Yanqing YU Chengwen WANG Xiaoliang li Zhihua WANG School of Environment Tsinghua UniversityBeijing 100084China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100084China Department of Chemistry Beijing University of Chemical TechnologyBeijing 100029China

Catalytic fast pyrolysis （CFP） of Kraft lignins with HZSM-5 zeolite for producing aromatics was investigated using analytical pyrolysis methods. Two Kraft lignins were fast pyrolyzed in the absence and presence of HZSM-5 in a Curie-point pyrolyzer. Without the catalyst, fast pyrolysis of lignin predominantly produced phenols and guaiacols that were derived from the subunits of lignin. However, the presence of HZSM-5 changed the product distribution dramatically. As the SiO2/ A1203 ratio of HZSM-5 decreased from 200 to 25 and the catalyst-to-lignin ratio increased from 1 to 20, the lignin- derived oxygenates progressively decreased to trace and the aromatics increased substantially. The aromatic yield increased considerably as the pyrolysis temperature increased from 500~C to 650~C, but then decreased with yet further increase of pyrolysis temperature. Under optimal reaction conditions, the aromatic yields were 2.0 wt.% and 5.2 wt.% for the two lignins that had effective hydrogen indexes of 0.08 and 0.35.

关键词： lignin catalytic fast pyrolysis HZSM-5 zeolite aromatic hydrocarbon

新发展格局下高等教育高质量发展的必然、实然与应然

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大庆师范学院学报 2024年第1期44卷 121-128页

作者：李翔宇北京师范大学教育学部北京100875

“双循环”新发展格局是高等教育高质量发展必须紧密围绕的经济社会发展新格局。然而,当前我国高等教育在人才供给、科技支撑、区域均衡、专业结构、对外开放等方面依然面临着许多供求不平衡、发展不充分的现实问题,无法真正适应与满足... 详细信息

“双循环”新发展格局是高等教育高质量发展必须紧密围绕的经济社会发展新格局。然而,当前我国高等教育在人才供给、科技支撑、区域均衡、专业结构、对外开放等方面依然面临着许多供求不平衡、发展不充分的现实问题,无法真正适应与满足新发展格局对于高等教育高质量发展的更高要求,亦难以发挥高等教育高质量发展推动构建新发展格局的重要作用。发展是解决我国一切问题的基础和关键,可以从促进高等教育供给侧结构性改革,补足高等教育发展短板;优化区域间高等教育资源配置,办好人民满意的高等教育;深入实施创新驱动发展战略,提升高等教育自主创新能力;立足中国式高等教育现代化,开创高等教育对外开放新局面等方面着手,在新发展格局下推动实现高等教育高质量发展。

关键词：新发展格局高等教育高质量发展

驻所调解的纠纷化解实践:运行逻辑、问题与改革进路

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河南警察学院学报 2024年第1期33卷 96-107页

作者：李向玉广东警官学院治安系广东广州510232

作为传统东方经验的人民调解制度,在熟人社会的矛盾纠纷化解中发挥了重要作用。改革开放以来,受人口流动速度加快形成的陌生人社会影响,非专职化的人民调解运行机制日渐式微。与此同时,有困难找警察的矛盾处理思维方式,让有限的警力陷... 详细信息

作为传统东方经验的人民调解制度,在熟人社会的矛盾纠纷化解中发挥了重要作用。改革开放以来,受人口流动速度加快形成的陌生人社会影响,非专职化的人民调解运行机制日渐式微。与此同时,有困难找警察的矛盾处理思维方式,让有限的警力陷入烦琐的纠纷个案调处之中。由于部分基层警务人员年龄过大、民事法律知识欠缺和案多人少等问题叠加,导致非警务警情处置环节涉警舆情频发,亟须通过制度性创新予以化解。广东D市通过政府采购实现驻所调解员的专职化运作,辅以多元调解机制的同步双轨运行,达到压减警情和防范矛盾纠纷刑事转化的效果,为人民调解的顺畅实施提供了实践样本。但驻所调解运行中仍存在调解员流动性过强、调解经验及警务知识储备不足、相关机构联动性不足等问题。在新型纠纷偶发与传统矛盾多发的交织下,优化驻所调解机制运行,仍需在纠纷调解技巧提炼、调解案件分类分级、社会治理深度协同推进等方面调整完善。

关键词：驻所调解纠纷解决非警务警情预防警务

Evaluation of soil microbial toxicity of waste foundry sand for soil-related reuse

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Frontiers of Environmental Science & Engineering 2014年第1期8卷 89-98页

作者： Haifeng ZHANG Lu SU xiangyu li Jiane ZUO Guangli liU Yujue WANG State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China Yangtze Delta Region Institute of Tsinghua University Jiaxing 314000 China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and Engineering Sun Yat-sen University Guangzhou 510275 China

The relationship between the chemical con- taminants and soil microbial toxicity of waste foundry sand （WFS） was investigated. Five different types of WFS from typical ferrous, aluminum, and steel foundries in China were examined for total metals, leachable metals, and organic contaminants. The soil microbial toxicity of each WFS was evaluated by measuring the dehydrogenase activity （DHA） of a blended soil and WFS mixture and then comparing it to that of unblended soil. The results show that the five WFSs had very different compositions of metal and organic contaminants and thus exhibited very different levels of soil microbial inhibition when blended with soil. For a given WFS blended with soil in the range of 10wt.%-50wt.% WFS, the DHA decreased almost linearly with increased blending ratio. Furthermore, for a given blending ratio, the WFSs with higher concentrations of metal and organic contaminants exhibited greater microbial toxicity. Correlation analysis shows that the relationship between ecotoxicity and metal and organic contaminants of WFSs can be described by an empirical logarithmic linear model. This model may be used to control WFS blending ratios in soil-related applications based on chemical analysis results to prevent significant inhibition of soil microbial activity.

关键词： waste foundry sand toxicity bioassay soilmicrobial activity waste reuse

一种反舰导弹打击下补给船目标的易损性分析方法

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中国舰船研究 2024年第3期19卷 166-173页

作者：董泽恒李翔宇陈高杰中国人民解放军91388部队辽宁大连116041 国防科技大学理学院湖南长沙410073

[目的]针对目前在舰船目标易损性分析方法研究方面的迫切需求,提出一种反舰导弹打击下补给船目标的易损性分析方法。[方法]以某典型补给船为攻击目标,选择反舰导弹作为攻击武器,分析目标的构效关系。通过数值模拟得到反舰导弹内爆载荷... 详细信息

[目的]针对目前在舰船目标易损性分析方法研究方面的迫切需求,提出一种反舰导弹打击下补给船目标的易损性分析方法。[方法]以某典型补给船为攻击目标,选择反舰导弹作为攻击武器,分析目标的构效关系。通过数值模拟得到反舰导弹内爆载荷作用下补给船的动态响应,研究反舰导弹内爆载荷作用下关键部件的毁伤破坏及毁伤判据,得到补给船功能的毁伤程度。对补给船目标易损性进行分析,判断使其航行功能造成最大程度毁伤的攻击方法。[结果]形成了从目标构效关系分析、关键部件毁伤模式、毁伤准则与判据,到目标功能毁伤程度的易损性分析方法的流程。根据目标易损性分布信息,得出瞄准非冗余部件集中的位置进行打击可起到最强的攻击效果。[结论]可为舰船目标易损性的研究提供技术支撑,辅助决策火力筹划。

关键词：反舰导弹内爆载荷补给船功能毁伤程度易损性分析方法火力筹划

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