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Global Geology 2013年第3期16卷 159-163页

作者： xu Xiaohui chen Hui'e WANG Gangcheng College of Construction Engineering Jilin University

On the basis of geological investigating work and experimental studies on slide zone soil of one landslide in Tibet,the authors analyzed granulometric composition,clay mineral composition and physical and mechanical properties for the soil in the slide *** soil samples are gravel containing fine *** larger than 2 mm occupy the main proportion with the content 51.5%--68.5%.The relative content of clay minerals is *** clay minerals are illite smectite mixed layer and kaolinite,and their relative contents are 6%--13% and 4%-11%,*** main mineral ingredient is quartz and the relative content is over 30%.Therefore,the soil’s hydrophily is *** cohesion and internal friction angle are high,causing preferable physical-mechanical features of slide zone *** the basis of the obtained data,the landslide stability is evaluated by means of limit equilibrium *** safety factors are 3.191 and 1.92 respectively under both natural and normal water level *** study results show that the landslide is *** can provide the appropriate basis and reference for landslide stability evaluation and landslide control in Tibet.

关键词： slide zone soil granulometric composition clay mineral composition physical-mechanical proper-ty landslide stability analysis

H∞-Based Selective Inversion of Nonminimum-phase Systems for Feedback Controls

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 702-710页

作者： Dan Wang xu chen Department of Mechanical Engineering University of WashingtonSeattleWA 98195 USA IEEE

Stably inverting a dynamic system model is fundamental to subsequent servo designs. Current inversion techniques have provided effective model matching for feedforward ***, when the inverse models are to be implemented in feedback systems, additional considerations are demanded for assuring causality, robustness, and stability under closed-loop constraints. To bridge the gap between accurate model approximations and robust feedback performances, this paper provides a new treatment of unstable zeros in inverse design. We provide first an intuitive pole-zero-map-based inverse tuning to verify the basic principle of the unstable-zero treatment. From there, for general nonminimum-phase and unstable systems, we propose an optimal inversion algorithm that can attain model accuracy at the frequency regions of interest while constraining noise amplification elsewhere to guarantee system robustness. Along the way, we also provide a modern review of model inversion techniques. The proposed algorithm is validated on motion control systems and complex high-order systems.

关键词： H∞formulation model inversion nonminimum-phase zeros unstable systems

先秦时期西南民族交往交流交融研究——以什邡古蜀铜戈铭文释读为例

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文史杂志 2025年第1期 33-39页

作者：徐晨钱玉趾西南民族大学民族学与社会学学院四川省科学技术学会

四川什邡是古蜀腹地,什邡城关战国秦汉墓地编号为M59:21的AVI式铭文戈是从楚式戈演变而来的战国晚期蜀戈。戈上5个字符竖刻在胡部,系古蜀文字。古蜀族与彝族有亲缘关系。用彝文字符比对,借助“左言”(主语·宾语·谓语)语序,可以将什邡... 详细信息

四川什邡是古蜀腹地,什邡城关战国秦汉墓地编号为M59:21的AVI式铭文戈是从楚式戈演变而来的战国晚期蜀戈。戈上5个字符竖刻在胡部,系古蜀文字。古蜀族与彝族有亲缘关系。用彝文字符比对,借助“左言”(主语·宾语·谓语)语序,可以将什邡戈铭文释读为“虎(王)用以战斗的锋利铜戈”。铜戈也是中华民族共同体形成与发展的实物例证。

关键词：什邡铭文戈战国晚期铭文释读民族互融

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光电稳定平台的分数阶降阶自抗扰控制设计

电光与控制 2025年第1期32卷 95-99页

作者：陈旭邸宏伟林国余陈佳明南京信息工程大学自动化学院南京210000 南京信息工程大学江苏省大气环境与装备技术协同创新中心南京210000 南京智真电子科技股份有限公司南京210000

为了提高光电稳定平台的动态性能与抗干扰能力,提出一种分数阶降阶自抗扰控制(FO-RADRC)算法。首先,利用系统输出信号的可测性和可靠性,采用降阶线性扩张状态观测器,提高观测效率和精度;然后,采用分数阶PD(FOPD)作为控制律,从而增强系... 详细信息

为了提高光电稳定平台的动态性能与抗干扰能力,提出一种分数阶降阶自抗扰控制(FO-RADRC)算法。首先,利用系统输出信号的可测性和可靠性,采用降阶线性扩张状态观测器,提高观测效率和精度;然后,采用分数阶PD(FOPD)作为控制律,从而增强系统的稳定性和控制性能。通过数值仿真实验,与线性自抗扰算法和降阶线性自抗扰算法进行了对比分析。结果表明,所提算法在动态性能指标上均优于对比算法,且在不同频率的等效扰动作用下具有更强的扰动抑制能力。这些结果验证了所提改进算法在提升光电稳定平台控制效果方面的有效性和创新性。

关键词：光电稳定平台分数阶控制自抗扰控制降阶线性扩张状态观测器

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Fast algorithms for singular value decomposition and the inverse of nearly low-rank matrices

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National Science Review 2023年第6期10卷 24-27页

作者： chen xu Weiwei xu Kaili Jing Department of Mathematics and Statistics University of Ottawa School of Mathematics and Statistics Xi'an Jiao Tong University School of Mathematics and Statistics Nanjing University of Information Science and Technology

PROBLEM Matrix computation is a fundamental task in science and engineering;it is recognized as one of the seven computational’giants’of massive data analysis [1],analogous to the seven’dwarfs’in highperformance *** recent years,as the scale of datasets rapidly grows,analysts and engineers frequently need to deal with big matrices with a nearly lowrank *** big size of a matrix brings great numerical hurdles to matrix *** this work,we focus on two typical tasks in matrix computation:singular value decomposition (SVD) and matrix inverse on nearly low-rank matrices that are potentially of big sizes.

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Tool Positioning Algorithm Based on Smooth Tool Paths for 5-axis Machining of Sculptured Surfaces

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 851-858页

作者： xu Rufeng chen Zhitong chen Wuyi School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

The current research of the 5-axis tool positioning algorithm mainly focuses on searching the local optimal tool position without gouging and interference at a cutter contact（CC） point,while not considering the smoothness and continuity of a whole tool *** the surface curvature varies significantly,a local abrupt change of tool paths will *** abrupt change has a great influence on surface machining *** order to keep generated tool paths smooth and continuous,a five-axis tool positioning algorithm based on smooth tool paths is ***,the inclination angle,the tilt angle and offset distance of the tool at a CC point are used as design variables,and the machining strip width is used as an objective function,an optimization model of a local tool positioning algorithm is thus ***,a vector equation of tool path is derived by using the above optimization *** analyzing the equation,the main factors affecting the tool path quality are ***,a new tool position optimization model is established,and the detailed process of tool position optimization is also *** experiment is conducted to machine an aircraft turbine blade by using the proposed algorithm on a 5-axis blade grinding machine,and the machined blade surface is measured with a coordinate measuring machine（CMM）.Experimental and measured results show that the proposed algorithm can ensure tool paths are smooth and continuous,improve the tool path quality,avoid the local abrupt change of tool paths,and enhance machining quality and machining efficiency of sculptured surfaces.

关键词： tool position tool path smooth five-axis sculptured surfaces machining

Half-global discretization algorithm based on rough set theory

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Journal of Systems Engineering and Electronics 2009年第2期20卷 339-347页

作者： Tan xu chen Yingwu School of Information Systems & Management National Univ. of Defense Technology Changsha 410073 P. R. China

It is being widely studied how to extract knowledge from a decision table based on rough set theory. The novel problem is how to discretize a decision table having continuous attribute. In order to obtain more reasonable discretization results, a discretization algorithm is proposed, which arranges half-global discretization based on the correlational coefficient of each continuous attribute while considering the uniqueness of rough set theory. When choosing heuristic information, stability is combined with rough entropy. In terms of stability, the possibility of classifying objects belonging to certain sub-interval of a given attribute into neighbor sub-intervals is minimized. By doing this, rational discrete intervals can be determined. Rough entropy is employed to decide the optimal cut-points while guaranteeing the consistency of the decision table after discretization. Thought of this algorithm is elaborated through Iris data and then some experiments by comparing outcomes of four discritized datasets are also given, which are calculated by the proposed algorithm and four other typical algorithras for discritization respectively. After that, classification rules are deduced and summarized through rough set based classifiers. Results show that the proposed discretization algorithm is able to generate optimal classification accuracy while minimizing the number of discrete intervals. It displays superiority especially when dealing with a decision table having a large attribute number.

关键词： half-global discretization continuous condition attributes correlation coefficient rough entropy stability rough set theory

Unifying quantum heat transfer and superradiant signature in a nonequilibrium collective-qubit system:A polaron-transformed Redfield approach

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Chinese Physics B 2019年第5期28卷 48-56页

作者： xu-Min chen chen Wang Department of Physics Hangzhou Dianzi University Department of Physics Zhejiang Normal University

We investigate full counting statistics of quantum heat transfer in a collective-qubit system constructed by multiqubits interacting with two thermal baths. The nonequilibrium polaron-transformed Redfield approach embedded with an auxiliary counting field is applied to obtain the steady state heat current and fluctuations, which enables us to study the impact of the qubit–bath interaction in a wide regime. The heat current, current noise, and skewness are all found to clearly unify the limiting results in the weak and strong couplings. Moreover, the superradiant heat transfer is clarified as a system-size-dependent effect, and large number of qubits dramatically suppress the nonequilibrium superradiant signature.

关键词： quantum transport heat conduction phonons or vibrational states in low-dimensional structures and nanoscale materials nonequilibrium and irreversible thermodynamics

A pilot exploration with Posiphen to normalize amyloid precursor protein in Down syndrome

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Neural Regeneration Research 2021年第12期16卷 2420-2421页

作者： xu-Qiao chen Department of Neurosciences University of California San DiegoLa JollaCAUSA

Down syndrome(DS)pathology:DS is the most common cause of Alzheimer’s disease(AD)and has a known AD-causing genetic variation which is trisomy of the whole or part of Homo sapiens chromosome 21(HSA21)(chen and Mobley,2019a).Compared with AD,DS usually present with various symptoms and manifestations which are related to dysfunction of multiple body systems;the extra copies of the many genes present in HSA21 in DS can cause various developmental problems including neurodevelopmental deficits,which underlie the physical features in DS and may also contribute to the ADrelated neurological symptoms of DS like cognition decline(Antonarakis et al.,2020).

关键词： al. amyloid pathology

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基于图重构和子图挖掘的僵尸网络检测方法

郑州大学学报（工学版） 2025年第1期46卷 34-41页

作者：景永俊吴悔陈旭宋吉飞合肥工业大学计算机与信息学院安徽合肥230601 北方民族大学计算机科学与工程学院宁夏银川750021 国家(中卫)新型互联网交换中心宁夏中卫755000

针对伪装后僵尸网络主机难以检测的问题,提出一种基于图重构和子图挖掘的僵尸网络检测方法(GR-SGM)。首先,将网络数据转化为图数据,并对其进行重构以此增强主机节点特征表示;其次,基于重构图中拓扑结构、节点的特征和位置变化设计僵尸... 详细信息

针对伪装后僵尸网络主机难以检测的问题,提出一种基于图重构和子图挖掘的僵尸网络检测方法(GR-SGM)。首先,将网络数据转化为图数据,并对其进行重构以此增强主机节点特征表示;其次,基于重构图中拓扑结构、节点的特征和位置变化设计僵尸网络子图评分函数,以此捕捉伪装后的特征,提取出僵尸网络子图,并对原始图和重构图进行预检测,以提高检测的准确率和效率,减少重构误差;最后,对预检测结果和僵尸网络子图进行综合评分,以获取完整的僵尸网络信息。在ISCX2014僵尸网络数据集和CICIDS2017僵尸网络数据集上的实验结果表明:GR-SGM的检测准确率分别达到99.98%和99.91%,F 1分别达到99.94%和99.65%,相较于其他僵尸网络检测模型,GR-SGM能更加高效准确地识别僵尸网络节点,同时具有更低的误报率。

关键词：僵尸网络子图挖掘图重构网络安全预检测