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The romance of replication:Hand in hand,from dawn to dusk

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Science Bulletin 2024年第16期69卷 2474-2475页

作者： Runze Ma zijing liu Bing Zhu National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Key Laboratory of Epigenetic Regulation and Intervention Chinese Academy of SciencesBeijing 100101China New Cornerstone Science Laboratory Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Faithful DNA duplication is the fundamental event for all life *** to replicate the whole genome quickly and efficiently is a challenge that must be faced within every S phase of the cell cycle[1].Considering the increased size and complexity of mammalian genomes,it is plausible that the regulation of DNA replication is more intricate in *** of thousands of replication origins have been identified throughout mammalian genomes[2].Whether replication forks originated from different origins cooperate during replication is a long-term concern in the field.

关键词： originated field. replication

A Glorious Future——Interview with liu zijing,President of Guangdong Airport Management Group

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China Today 2006年第4期55卷 80-81页

作者： liu zijing, president of Guangdong Airport Management Group.

China Today: In your opinion, which of the developments that have taken place at the Guangdong Airport Management Group and Baiyun International Airport during the 10th Five-Year Plan are most significant? liu zijing:... 详细信息

关键词：广东航空公司企业文化经营策略航空安全

面向争端预防的投资者—国家争端解决机制改革路径及其中国方案

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经贸法律评论 2024年第3期 24-45页

作者：刘子婧浙江大学光华法学院

从介入纠纷的时机和目标上看,可以将ISDS机制改革分为“争端解决”与“争端预防”两种面向。以往的改革倡议主要集中于争端解决面向,聚焦于对国际投资条约仲裁的制度修补和程序再造,但随着改革迈入深水区,该路径日渐陷入僵持,暴露出制... 详细信息

从介入纠纷的时机和目标上看,可以将ISDS机制改革分为“争端解决”与“争端预防”两种面向。以往的改革倡议主要集中于争端解决面向,聚焦于对国际投资条约仲裁的制度修补和程序再造,但随着改革迈入深水区,该路径日渐陷入僵持,暴露出制度变迁成本高昂、利益分配与再平衡困难、强调对抗而非合作的局限。面向争端预防的ISDS改革路径有望成为未来新出口,该路径以DPMMs为圆心,强调提前预防、及早介入和降级化解投资争端。近年来,面向争端预防的改革机制日益受到东道国关注,我国外商投资投诉制度的勃兴也印证了这一趋势。为因应此现实,应当纳入面向争端预防的DPMMs作为改革新措施,采取全生命周期式的治理思维促进外商投资,预防和管理投资争端。冷静期条款、监察专员和投诉机制为改革提供了具体制度供给,有望为处于窗口期的ISDS改革提供中国方案。

关键词： ISDS改革争端预防争端解决外商投资投诉国际投资条约仲裁

A new hybrid aerodynamic optimization framework based on differential evolution and invasive weed optimization

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Chinese Journal of Aeronautics 2018年第7期31卷 1437-1448页

作者： zijing liu Xuejun liu Xinye CAI College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics

Since many aerodynamic optimization problems in the area of aeronautics contain highly nonlinear objectives and multiple local optima, it is still a challenge for most of the traditional optimization methods to find the global optima. In this paper, a new hybrid optimization framework based on Differential Evolution and Invasive Weed Optimization（IWO_DE/Ring） is developed, which combines global and local search to improve the performance, where a Multiple-Output Gaussian Process（MOGP） is used as the surrogate model. We first use several test functions to verify the performance of the IWO_DE/Ring method, and then apply the optimization framework to a supercritical airfoil design problem. The convergence and the robustness of the proposed framework are compared against some other optimization methods. The IWO_DE/Ringbased approach provides much quicker and steadier convergence than the traditional *** results show that the stability of the dynamic optimization process is an important indication of the confidence in the obtained optimum, and the proposed optimization framework based on IWO_DE/Ring is a reliable and promising alternative for complex aeronautical optimization problems.

关键词： Airfoil design Differential evolution Genetic algorithms Invasive weed optimization Optimization

CON-MVX:一种基于容器技术的多变体执行系统

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信息安全学报 2024年第2期9卷 47-58页

作者：刘子敬张铮席睿成朱鹏喆邬江兴数字工程与先进计算国家重点实验室郑州450001 国家数字交换系统工程技术研究中心郑州450002

多变体执行是一种网络安全防御技术,其利用软件多样性生成等价异构的执行体,将程序输入分发至多个执行体并行执行,通过监控和比较执行体的状态来达到攻击检测的目的。相较于传统的补丁式被动防御技术,多变体执行不依赖于具体的攻击威胁... 详细信息

多变体执行是一种网络安全防御技术,其利用软件多样性生成等价异构的执行体,将程序输入分发至多个执行体并行执行,通过监控和比较执行体的状态来达到攻击检测的目的。相较于传统的补丁式被动防御技术,多变体执行不依赖于具体的攻击威胁特征进行分析,而是通过构建系统的内生安全能力来对大多数已知、甚至未知的漏洞做出有效防御。近年来,多变体执行技术在不断改进和完善,但是误报问题是制约其发展的主要因素。本文针对多变体执行产生误报的原因进行了详细分析,并在此基础上提出利用容器技术实现多变体执行系统在解决误报问题上的优势。为提升多变体执行技术的可用性,本文设计并实现了一种基于容器技术的多变体执行系统CON-MVX,有效解决传统多变体执行系统的误报问题。CON-MVX利用多个经过运行时随机化技术构建的异构容器作为执行体,使用可重构的模块化组件和独立的容器管理工具对容器执行体进行编排管理,建立进程间监控器CGMon,在内核层级实现对多个执行体的输入同步和输出裁决。同时,为满足与客户端良好交互性,建立中继端口策略,保证系统运行状态的正常反馈。实验结果表明, CON-MVX在保证安全能力的前提下,能有效降低多变体执行系统的误报率,在双冗余度执行条件下使用SPEC CPU 2006测试集测试时,系统带来的平均额外性能损耗不超过15%。

关键词：多变体执行容器技术软件漏洞安全能力

基于遗传模拟退火算法的子阵级自适应波束形成

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电讯技术 2024年第9期64卷 1480-1485页

作者：刘子敬陈曦施庆展崔开博国防科技大学CEMEE国家重点实验室长沙410073

在阵列天线信号处理中,采用子阵级自适应波束形成技术可以降低算法复杂度和系统成本。针对子阵级自适应波束形成中最优子阵划分问题,提出了一种基于遗传模拟退火算法的阵列天线子阵最优划分方法。通过线性约束最小方差算法计算不同子阵... 详细信息

在阵列天线信号处理中,采用子阵级自适应波束形成技术可以降低算法复杂度和系统成本。针对子阵级自适应波束形成中最优子阵划分问题,提出了一种基于遗传模拟退火算法的阵列天线子阵最优划分方法。通过线性约束最小方差算法计算不同子阵划分下的自适应权矢量,形成自适应天线方向图,以方向图的最大旁瓣电平比作为成本函数,迭代优化得到最大旁瓣电平最优的子阵划分形式。仿真结果表明,使用该方法得到的非均匀子阵划分阵列天线其自适应方向图最大旁瓣电平能降低至-19 dB。通过对比分析不同子阵划分形式以及不同规模阵面的自适应方向图验证了该方法的可行性与有效性。

关键词：阵列天线子阵划分自适应波束形成遗传模拟退火

The modulation of catalytic active site and support to construct high-efficiency ZnS/NC-X electrocatalyst for nitrogen reduction

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Nano Research 2022年第9期15卷 7903-7909页

作者： Peng Wang Sijia Zhao zijing liu Caiyun Han Shuang Wang Jinping Li College of Environmental Science and Engineering Taiyuan University of TechnologyJinzhong 030600China Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization Taiyuan University of TechnologyTaiyuan 030024China

Transition metals are a kind of promising catalysts to apply into electrocatalytic synthesis ammonia by virtue of abundant reserves and low ***,many widely used transition metal catalysts usually face the challenge to realize satisfactory catalytic results mainly resulting from the match between catalytic active site and ***,a new-type ZnS/NC-X electrocatalyst was reported by in-situ sulfidation of zeolitic imidazolate framework-8(ZIF-8),where the metal nodes of ZIF-8 reacted with dibenzyl disulfide(BDS)to obtain ZnS nanoparticles and the framework of ZIF-8 was carbonized to form the ***,catalytic active sites(ZnS nanoparticles)and support(NC-X)were adjusted in detailed by changing the ratio of ZIF-8 and *** a result,when the mass ratio of ZIF-8 and BDS was 1:1,the resulted ZnS/NC-2 catalyst achieved a remarkable NH3 yield of 65.60μg·h^(−1)·mg^(−1)cat.,Faradaic efficiency(FE)of 18.52%at−0.4 V vs reversible hydrogen electrode(RHE)in 0.05 M H2SO4 and catalytic stability,which outperformed most reported transition metal *** matching catalytic active site and support make our strategy promising for wide catalytic applications.

关键词： ZnS/NC-X electrocatalyst nitrogen reduction reaction support catalytic active site

Full lifetime demonstration of a Micro-Cathode-Arc thruster evolution characteristics

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Chinese Journal of Aeronautics 2024年第6期37卷 38-49页

作者： Zhe ZHANG zijing ZHAO Xiangyang liu Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

Ground lifetime test is the most crucial experiment to assess the performance,*** flight qualification of electric propulsion,and it can bring new insights for understanding the operation *** work demonstrates a full lifetime test of 140000 cycles on a Micro-Cathode-Arc Thruster(μCAT)with 160μs charging time and 86 mJ charging energy.A four-probe resistivity measurement method is utilized to investigate variations in the conductive film thickness and resistivity throughout the thruster *** film parameters show that the lifetime of theμCAT can be divided into three *** the initial stage,the film thickness decreases by 1.2μm and the resistivity increases significantly due to the high discharge intensity and intense film ablation;In the steady stage,the change of the film thickness is within 5%,and the resistivity of the film increases slowly from 0.050Ω·mm to 0.223Ω·*** the end stage,the resistivity exponentially increases from 0.223Ω·mm to 1.176Ω·mm,with the increase accounting for 81%,ultimately resulting in the failure of the thruster open ***,the evolution of discharge parameters,and the variation of plume parameters are measured throughout the *** discharge characteristics also show significant differences in the duration of voltage and current in these three *** results of plume shape and plasma parameters are also well con-sistent with the discharge parameters and film *** results suggest that,for evaluating the steady stage lifetime of thrusters,the film thickness is the best indicator compared to the variations in resistivity and voltage-current *** the end stage,the plasma plume *** duration,and plume parameters can conveniently and clearly characterize the thruster failures and irregularity.

关键词： Electric propulsion Lifetime test Micro-Cathode-Arc Thruster(uCAT) Conductive film Discharge characteristics Plasma parameters

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基于风云四号卫星数据的南海海雾遥感监测

气象与环境科学 2024年第2期47卷 28-35页

作者：张毅靳奎峰刘子菁刘厚智杨颖璨何沐全广州市突发事件预警信息发布中心广州514300 广东省气象服务中心广州510630 广州气象卫星地面站广州510630

基于中国新一代静止气象卫星FY-4A所携带的辐射成像仪AGRI(Advanced Geosynchronous Radiation Imager)观测数据和地面能见度观测资料,通过不同组合的可见光通道、近红外通道、中远红外通道的数据,开展南海区域海雾遥感监测研究。针对... 详细信息

基于中国新一代静止气象卫星FY-4A所携带的辐射成像仪AGRI(Advanced Geosynchronous Radiation Imager)观测数据和地面能见度观测资料,通过不同组合的可见光通道、近红外通道、中远红外通道的数据,开展南海区域海雾遥感监测研究。针对海雾在遥感影像中与下垫面和云的不同特征,通过使用最小二乘法动态拟合选取最优度的方法实现海雾与下垫面的分离,使用云顶高度阈值的方法实现海雾与中高云的分离,使用纹理特征识别和海雾检测指数的方法实现海雾和低云在日间的分离,使用薄低云检测指数的方法实现海雾和低云在夜间的分离,并将海雾判识结果与2018年广东沿海地基观测资料进行对比。结果表明:(1)使用最小二乘法动态拟合选取最优度的方法,对海雾和下垫面的区分有着良好的效果,使用纹理特征识别和海雾检测指数的方法对海雾和低云的区分也有一定的改进作用。(2)该算法对3月份发生的海雾的识别准确率最高,为85.45%,虚警率最低,为20.94%;对5月份发生的海雾识别准确率最低,为58.70%;对1月份发生的海雾虚警率最高,为30.95%。该海雾监测算法平均准确率为76.37%,虚警率约为26.08%。

关键词：风云四号卫星海雾南海遥感监测