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Application of Dynamic Linear Detecting Method in Data Processing of the Portable Blood Sugar Analyzer
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作者 Xiaohao Wang Ran Liu +2 位作者 Fei Tang Yangchun Yu Zhaoying Zhou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期80-82,共3页
In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (... In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (5%),was used for data processing and could solve the problem caused by the phenomenon of substrate depleting occurred following the redox reaction in portable blood sugar analyzer.By contrast to the conventional end-point method,the dynamic linear detecting method is based on multipoint data collecting.Experiments of measuring the calibration glucose solution with 8 various concentrations from 50 mg/dl to 400 mg/dl were carried out with the analyzer developed by our group.The linear regression curve,whose correlation for the data was 0.9995 and the residual was 2.8080,were obtained.The obtained correlation,residual, and the computation workload are all fit for the portable blood sugar analyzer. 展开更多
关键词 data processing portable blood sugar analyzer dynamic linear detecting method
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A symplectic finite element method based on Galerkin discretization for solving linear systems
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作者 Zhiping QIU Zhao WANG Bo ZHU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第8期1305-1316,共12页
We propose a novel symplectic finite element method to solve the structural dynamic responses of linear elastic systems.For the dynamic responses of continuous medium structures,the traditional numerical algorithm is ... We propose a novel symplectic finite element method to solve the structural dynamic responses of linear elastic systems.For the dynamic responses of continuous medium structures,the traditional numerical algorithm is the dissipative algorithm and cannot maintain long-term energy conservation.Thus,a symplectic finite element method with energy conservation is constructed in this paper.A linear elastic system can be discretized into multiple elements,and a Hamiltonian system of each element can be constructed.The single element is discretized by the Galerkin method,and then the Hamiltonian system is constructed into the Birkhoffian system.Finally,all the elements are combined to obtain the vibration equation of the continuous system and solved by the symplectic difference scheme.Through the numerical experiments of the vibration response of the Bernoulli-Euler beam and composite plate,it is found that the vibration response solution and energy obtained with the algorithm are superior to those of the Runge-Kutta algorithm.The results show that the symplectic finite element method can keep energy conservation for a long time and has higher stability in solving the dynamic responses of linear elastic systems. 展开更多
关键词 Galerkin finite element method linear system structural dynamic response symplectic difference scheme
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A Dynamic Active-Set Method for Linear Programming
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作者 Alireza Noroziroshan H. W. Corley Jay M. Rosenberger 《American Journal of Operations Research》 2015年第6期526-535,共10页
An efficient active-set approach is presented for both nonnegative and general linear programming by adding varying numbers of constraints at each iteration. Computational experiments demonstrate that the proposed app... An efficient active-set approach is presented for both nonnegative and general linear programming by adding varying numbers of constraints at each iteration. Computational experiments demonstrate that the proposed approach is significantly faster than previous active-set and standard linear programming algorithms. 展开更多
关键词 CONSTRAINT Optimal SELECTION Techniques dynamic Active-Set methods LARGE-SCALE linear PROGRAMMING linear PROGRAMMING
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SYNCHRONIZATION OF MASTER-SLAVE MARKOVIAN SWITCHING COMPLEX DYNAMICAL NETWORKS WITH TIME-VARYING DELAYS IN NONLINEAR FUNCTION VIA SLIDING MODE CONTROL 被引量:3
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作者 M.Syed ALI J.YOGAMBIGAI 曹进德 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期368-384,共17页
In this article, a synchronization problem for master-slave Markovian switching complex dynamical networks with time-varying delays in nonlinear function via sliding mode control is investigated. On the basis of the a... In this article, a synchronization problem for master-slave Markovian switching complex dynamical networks with time-varying delays in nonlinear function via sliding mode control is investigated. On the basis of the appropriate Lyapunov-Krasovskii functional,introducing some free weighting matrices, new synchronization criteria are derived in terms of linear matrix inequalities(LMIs). Then, an integral sliding surface is designed to guarantee synchronization of master-slave Markovian switching complex dynamical networks, and the suitable controller is synthesized to ensure that the trajectory of the closed-loop error system can be driven onto the prescribed sliding mode surface. By using Dynkin's formula, we established the stochastic stablity of master-slave system. Finally, numerical example is provided to demonstrate the effectiveness of the obtained theoretical results. 展开更多
关键词 滑模变结构控制 非线性函数 主从系统 网络同步 时变时滞 切换 LYAPUNOV 线性矩阵不等式
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Application of scaled boundary finite element method in static and dynamic fracture problems 被引量:2
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作者 Zhenjun Yang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第3期243-256,共14页
放大边界有限元素方法(SBFEM ) 是联合两个有限元素方法的优点的一个最近发达的数字方法(女性) 并且边界元素方法(BEM ) 并且与它的自己的特殊特征也。最突出的优点之一从其在裂缝尖端的奇特是经分解的答案代表了的压力直接是它精明的... 放大边界有限元素方法(SBFEM ) 是联合两个有限元素方法的优点的一个最近发达的数字方法(女性) 并且边界元素方法(BEM ) 并且与它的自己的特殊特征也。最突出的优点之一从其在裂缝尖端的奇特是经分解的答案代表了的压力直接是它精明的压力紧张因素(SIF ) 的能力。这个优点在这研究被拿为静态、动态的破裂问题建模。为静态的问题,象一样简单的一个重新协调的算法在 BEM 使用当保留概论和灵活性时,被开发女性。混合模式裂缝繁殖的充分自动的建模然后被把重新协调的算法与一个繁殖标准相结合认识到。为动态破裂问题,在频率领域管理方程的 SBFEM 的一个最新发达的增加系列的答案被使用计算动态 SIF。三个飞机问题被建模。数字结果证明 SBFEM 罐头精确地预言静态、动态的 SIF,击碎路径和负担排水量曲线,用仅仅传统的有限元素方法通常需要的自由的很少的度。 展开更多
关键词 比例边界有限元法 动态应力强度因子 混合模裂缝传播 线性弹性力学
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Prediction of Link Failure in MANET-IoT Using Fuzzy Linear Regression
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作者 R.Mahalakshmi V.Prasanna Srinivasan +1 位作者 S.Aghalya D.Muthukumaran 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1627-1637,共11页
A Mobile Ad-hoc NETwork(MANET)contains numerous mobile nodes,and it forms a structure-less network associated with wireless links.But,the node movement is the key feature of MANETs;hence,the quick action of the nodes ... A Mobile Ad-hoc NETwork(MANET)contains numerous mobile nodes,and it forms a structure-less network associated with wireless links.But,the node movement is the key feature of MANETs;hence,the quick action of the nodes guides a link failure.This link failure creates more data packet drops that can cause a long time delay.As a result,measuring accurate link failure time is the key factor in the MANET.This paper presents a Fuzzy Linear Regression Method to measure Link Failure(FLRLF)and provide an optimal route in the MANET-Internet of Things(IoT).This work aims to predict link failure and improve routing efficiency in MANET.The Fuzzy Linear Regression Method(FLRM)measures the long lifespan link based on the link failure.The mobile node group is built by the Received Signal Strength(RSS).The Hill Climbing(HC)method selects the Group Leader(GL)based on node mobility,node degree and node energy.Additionally,it uses a Data Gathering node forward the infor-mation from GL to the sink node through multiple GL.The GL is identified by linking lifespan and energy using the Particle Swarm Optimization(PSO)algo-rithm.The simulation results demonstrate that the FLRLF approach increases the GL lifespan and minimizes the link failure time in the MANET. 展开更多
关键词 Mobile ad-hoc network fuzzy linear regression method link failure detection particle swarm optimization hill climbing
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Dynamic inverse control of feedback linearization in ballistic correction based on nose cone swinging
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作者 秦华伟 王华 《Journal of Central South University》 SCIE EI CAS 2013年第9期2447-2453,共7页
It is a complicated nonlinear controlling problem to conduct a two-dimensional trajectory correction of rockets.By establishing the aerodynamic correction force mathematical model of rockets on nose cone swinging,the ... It is a complicated nonlinear controlling problem to conduct a two-dimensional trajectory correction of rockets.By establishing the aerodynamic correction force mathematical model of rockets on nose cone swinging,the linear control is realized by the dynamic inverse nonlinear controlling theory and the three-time-scale separation method.The control ability and the simulation results are also tested and verified.The results show that the output responses of system track the expected curve well and the error is controlled in a given margin.The maximum correction is about±314 m in the lengthwise direction and±1 212 m in the crosswise direction from the moment of 5 s to the drop-point time when the angle of fire is 55°.Thus,based on the dynamic inverse control of feedback linearization,the trajectory correction capability of nose cone swinging can satisfy the requirements of two-dimensional ballistic correction,and the validity and effectiveness of the method are proved. 展开更多
关键词 动态逆控制 反馈线性化 弹道修正 摆动 鼻锥 非线性控制理论 基础 修正能力
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基于等效线性化的SISC隔震框架结构动力响应分析
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作者 张广泰 陈畅 +1 位作者 梁本帅 章金鹏 《工程抗震与加固改造》 2024年第1期1-8,27,共9页
为探究采用废旧轮胎隔震垫(STP)制成的柱下新型隔震装置(SISC)在村镇框架结构中的隔震效果,通过SAP2000建立隔震与非隔震三层框架结构模型,利用简化计算方法进行初步布置,采用反应谱法及时程分析法对比了隔震前后层间剪力比,并进行了上... 为探究采用废旧轮胎隔震垫(STP)制成的柱下新型隔震装置(SISC)在村镇框架结构中的隔震效果,通过SAP2000建立隔震与非隔震三层框架结构模型,利用简化计算方法进行初步布置,采用反应谱法及时程分析法对比了隔震前后层间剪力比,并进行了上部结构的动力响应分析。结果表明:简化计算方法、振型分解反应谱法及时程分析法得到的底部剪力比分别为0.4207、0.4091、0.4491;隔震结构较非隔震结构自振周期延长2~3倍,由时程分析法可得隔震结构中上部结构层间位移角、顶层加速度较非隔震结构最大分别降低86.48%、49.26%,均满足规范限值要求,上部结构整体呈现平动;SISC隔震框架结构按照简化计算方法进行SISC初步布置具有可行性,该研究成果为STP隔震体系在村镇框架结构中的实际应用提供参考。 展开更多
关键词 STP 柱下新型隔震装置 框架结构 等效线性化 动力响应
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高震区斜坡式护岸的岸坡稳定性分析
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作者 卢生军 郭隆洽 《水运工程》 2024年第3期159-164,共6页
对位于菲律宾高震区的某斜坡式护岸结构的岸坡进行稳定性评估,分析国际上主流抗震设计规范,结合该工程的具体设计条件,提出合适的地震岸坡稳定分析方法、稳定标准和分析流程,并采用Newmark法和非线性动力分析对该护岸的震后残余位移进... 对位于菲律宾高震区的某斜坡式护岸结构的岸坡进行稳定性评估,分析国际上主流抗震设计规范,结合该工程的具体设计条件,提出合适的地震岸坡稳定分析方法、稳定标准和分析流程,并采用Newmark法和非线性动力分析对该护岸的震后残余位移进行计算。结果表明:高震区的岸坡稳定分析宜以控制位移为目标,水准1、2地震下的残余位移宜分别不超过5、30 cm;当采用Newmark法计算时宜取其上限位移,而通过非线性动力分析可获得岸坡残余位移和最大剪应变等的分布,从而对地震下的岸坡稳定做更为全面的设计和评估。 展开更多
关键词 高震区 岸坡稳定 NEWMARK法 非线性动力分析
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动态场景下基于YOLOv5和几何约束的视觉SLAM算法
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作者 王鸿宇 吴岳忠 +1 位作者 陈玲姣 陈茜 《包装工程》 CAS 2024年第3期208-217,共10页
目的移动智能体在执行同步定位与地图构建(Simultaneous Localization and Mapping,SLAM)的复杂任务时,动态物体的干扰会导致特征点间的关联减弱,系统定位精度下降,为此提出一种面向室内动态场景下基于YOLOv5和几何约束的视觉SLAM算法... 目的移动智能体在执行同步定位与地图构建(Simultaneous Localization and Mapping,SLAM)的复杂任务时,动态物体的干扰会导致特征点间的关联减弱,系统定位精度下降,为此提出一种面向室内动态场景下基于YOLOv5和几何约束的视觉SLAM算法。方法首先,以YOLOv5s为基础,将原有的CSPDarknet主干网络替换成轻量级的MobileNetV3网络,可以减少参数、加快运行速度,同时与ORB-SLAM2系统相结合,在提取ORB特征点的同时获取语义信息,并剔除先验的动态特征点。然后,结合光流法和对极几何约束对可能残存的动态特征点进一步剔除。最后,仅用静态特征点对相机位姿进行估计。结果在TUM数据集上的实验结果表明,与ORB-SLAM2相比,在高动态序列下的ATE和RPE都减少了90%以上,与DS-SLAM、Dyna-SLAM同类型系统相比,在保证定位精度和鲁棒性的同时,跟踪线程中处理一帧图像平均只需28.26 ms。结论该算法能够有效降低动态物体对实时SLAM过程造成的干扰,为实现更加智能化、自动化的包装流程提供了可能。 展开更多
关键词 视觉SLAM 动态场景 目标检测 光流法 对极几何约束
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月球车与月壤交互作用的离散元-多体动力学耦合建模
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作者 徐鸿 雷波 刘锦阳 《振动与冲击》 EI CSCD 2024年第4期239-249,共11页
目前,对于散体颗粒物质与复杂机械系统的耦合作用研究,面临着跨尺度、计算规模庞大以及非光滑表面的接触检测困难等问题。为了探究月球车与月壤交互作用,首先对颗粒-多体耦合系统动力学建模与接触算法进行研究。分别用离散元方法(discre... 目前,对于散体颗粒物质与复杂机械系统的耦合作用研究,面临着跨尺度、计算规模庞大以及非光滑表面的接触检测困难等问题。为了探究月球车与月壤交互作用,首先对颗粒-多体耦合系统动力学建模与接触算法进行研究。分别用离散元方法(discrete element method, DEM)和多体动力学(multibody dynamics, MBD)笛卡尔方法建立了散体球形颗粒和含约束多体系统的动力学模型,并基于Hertz-Mindlin模型计算颗粒与刚体的接触力,在此基础上给出顺序耦合策略,建立了离散元和多体耦合的动力学模型。针对月球车齿状车轮的非光滑表面与颗粒之间接触检测规模庞大的问题,提出了非光滑形状物体的分区域局部检测方法,降低了局部检测的规模。通过对比圆柱体冲击颗粒的试验和仿真结果,验证了离散元-多体耦合模型的准确性。在耦合动力学建模和接触算法研究的基础上,对具有齿状车轮的月球车在月壤上行驶过程进行动力学仿真,研究不同驱动参数下的系统动力学特性以及不同轮胎形状对行驶运动的影响,研究结果表明,交错形轮齿的月球车相较直齿形轮齿前进距离多14%,前进效率较高,该研究对月球车的设计具有理论指导意义。 展开更多
关键词 离散元方法(DEM) 多体动力学(MBD) 月球车 耦合建模 高效接触检测
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分段线性系统经典数学模型的修正与动力学分析
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作者 张瑞良 申永军 韩东 《力学学报》 EI CAS CSCD 2024年第1期225-235,共11页
由于间隙的存在,很多机械系统可以简化为分段线性模型,而简化后的模型中副簧系统通常包含阻尼.在大多数文献建立的数学模型中,主、副系统的接触点与分离点固定在间隙处.文章研究发现,由于副簧系统中弹簧与阻尼的力学特性不同,主、副系... 由于间隙的存在,很多机械系统可以简化为分段线性模型,而简化后的模型中副簧系统通常包含阻尼.在大多数文献建立的数学模型中,主、副系统的接触点与分离点固定在间隙处.文章研究发现,由于副簧系统中弹簧与阻尼的力学特性不同,主、副系统的接触点与分离点位置实际上是随着系统参数和运动状态而变化的.若忽视这一点,后续的包括分岔和混沌在内的动力学分析就会出现误差甚至错误.首先基于经典的数学模型,用数值方法揭示了在简谐激励下主系统未返回到间隙处就与副簧系统提前分离,证明了经典数学模型的不当之处.进一步研究发现主系统不仅会出现提前分离,还会出现接触滞后的现象.因此对系统的接触与分离条件提出了修正,得到了更合理的数学模型.研究发现修正后的接触点、分离点位置与修正前相差较大,修正后的幅频响应曲线与修正前存在一定差别;在复杂运动中,修正前后的运动性质也可能发生改变,证明了修正后的模型更加合理,更能反映工程实际.然后,采用平均法并对平均法的积分区间进行推广,求得了修正模型的幅频响应的解析解,并通过龙格库塔法验证了解析解的正确性.对解析解进行稳定性分析,得到了解析解的稳定性判别式.最后,探究了修正模型的副簧系统参数对主系统幅频响应的影响. 展开更多
关键词 非线性振动 分段线性系统 平均法 动力学行为 接触
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加工误差对静压气浮主轴静动态性能的影响
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作者 李瑞瑞 李运堂 +3 位作者 王鹏峰 叶月亮 李孝禄 陈源 《机械科学与技术》 CSCD 2024年第4期650-659,共10页
为了改善静压气浮主轴静动态性能,研究了非均匀分布变节流孔直径静压气浮主轴结构。基于有限差分和线性小扰动法分析节流孔直径和分布不均匀性对主轴承载能力的影响,研究了轴套存在周向或轴向加工误差(正弦波纹、矩形波纹和三角波纹)对... 为了改善静压气浮主轴静动态性能,研究了非均匀分布变节流孔直径静压气浮主轴结构。基于有限差分和线性小扰动法分析节流孔直径和分布不均匀性对主轴承载能力的影响,研究了轴套存在周向或轴向加工误差(正弦波纹、矩形波纹和三角波纹)对主轴静动态性能的影响。结果表明:节流孔直径系数为0.9~0.95时,承载能力提升最明显;周向或轴向加工误差有助于提高主轴承载能力;矩形和三角形波纹提高新型主轴承载能力更显著;轴向矩形波纹、三角波纹更有助于提高主轴稳定性;随着加工误差幅值增大,主轴稳定性降低。 展开更多
关键词 静压气浮主轴 有限差分法 线性小扰动法 加工误差 静态性能 动态性能
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在线优化参数的神经网络预测监督控制
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作者 侯小秋 《陕西理工大学学报(自然科学版)》 2024年第2期38-44,共7页
使用具有辅助变量的全格式动态线性化方法逼近系统,构建了神经网络监督控制预测模型。利用线性跟踪-微分器建立过渡过程,应用线性扩张状态观测器估计输出预测值及其微分,给出了线性PID控制算法。根据对角回归神经网络构成直接逆控制,提... 使用具有辅助变量的全格式动态线性化方法逼近系统,构建了神经网络监督控制预测模型。利用线性跟踪-微分器建立过渡过程,应用线性扩张状态观测器估计输出预测值及其微分,给出了线性PID控制算法。根据对角回归神经网络构成直接逆控制,提出了改进的控制目标函数。依据非线性递推最小二乘法在线优化了PID控制参数和对角回归神经网络的连接权。当系统控制误差大于一定值时,重置PID控制参数。最后提出了在线优化参数的神经网络预测监督控制,克服了已有的神经网络监督控制存在建模难的问题。仿真研究结果表明控制算法的响应具有理想性能。 展开更多
关键词 神经网络监督控制 非线性系统 线性PID控制 全格式动态线性化方法 对角回归神经网络 非线性递推最小二乘法
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遥感信息技术在地震灾害检测中的应用方法
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作者 刘瑞 《现代信息科技》 2024年第5期171-174,共4页
为实现对地震灾害的精准检测,研究基于遥感信息技术的地震灾害检测方法。引进遥感信息技术,搭建数字化遥感图像可视化处理模型,进行图像测绘与成像;引进ICA算法,提取地震灾害图像的纹理特征;按照输出时序对纹理特征进行排序,得到具有连... 为实现对地震灾害的精准检测,研究基于遥感信息技术的地震灾害检测方法。引进遥感信息技术,搭建数字化遥感图像可视化处理模型,进行图像测绘与成像;引进ICA算法,提取地震灾害图像的纹理特征;按照输出时序对纹理特征进行排序,得到具有连续化特征的区域地质变化影像,实现基于数据动态监测的地震发生点定位。实验结果证明,该文设计的地震灾害检测方法,不仅可以实现对地震灾害发生点的定位,还可以确保灾害定位结果的精准度。 展开更多
关键词 遥感信息技术 地质测绘成像 检测方法 纹理特征 动态监测 地震灾害
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Spatio-temporal dynamics of vegetation in Jungar Banner of China during 2000–2017 被引量:5
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作者 LI Xinhui LEI Shaogang +2 位作者 CHENG Wei LIU Feng WANG Weizhong 《Journal of Arid Land》 SCIE CSCD 2019年第6期837-854,共18页
It is known that the exploitation of opencast coal mines has seriously damaged the environments in the semi-arid areas.Vegetation status can reliably reflect the ecological degeneration and restoration in the opencast... It is known that the exploitation of opencast coal mines has seriously damaged the environments in the semi-arid areas.Vegetation status can reliably reflect the ecological degeneration and restoration in the opencast mining areas in the semi-arid areas.Long-time series MODIS NDVI data are widely used to simulate the vegetation cover to reflect the disturbance and restoration of local ecosystems.In this study, both qualitative(linear regression method and coefficient of variation(CoV)) and quantitative(spatial buffer analysis, and change amplitude and the rate of change in the average NDVI) analyses were conducted to analyze the spatio-temporal dynamics of vegetation during 2000–2017 in Jungar Banner of Inner Mongolia Autonomous Region, China, at the large(Jungar Banner and three mine groups) and small(three types of functional areas: opencast coal mining excavation areas, reclamation areas and natural areas) scales.The results show that the rates of change in the average NDVI in the reclamation areas(20%–60%) and opencast coal mining excavation areas(10%–20%) were considerably higher than that in the natural areas(<7%).The vegetation in the reclamation areas experienced a trend of increase(3–5 a after reclamation)-decrease(the sixth year of reclamation)-stability.The vegetation in Jungar Banner has a spatial heterogeneity under the influences of mining and reclamation activities.The ratio of vegetation improvement area to vegetation degradation area in the west, southwest and east mine groups during 2000–2017 was 8:1, 20:1 and 33:1, respectively.The regions with the high CoV of NDVI above 0.45 were mainly distributed around the opencast coal mining excavation areas, and the regions with the CoV of NDVI above 0.25 were mostly located in areas with low(28.8%) and medium-low(10.2%) vegetation cover.The average disturbance distances of mining activities on vegetation in the three mine groups(west, southwest and east) were 800, 800 and 1000 m, respectively.The greater the scale of mining, the farther the disturbance distances of mining activities on vegetation.We conclude that vegetation reclamation will certainly compensate for the negative impacts of opencast coal mining activities on vegetation.Sufficient attention should be paid to the proportional allocation of plant species(herbs and shrubs) in the reclamation areas, and the restored vegetation in these areas needs to be protected for more than 6 a.Then, as the repair time increased, the vegetation condition of the reclamation areas would exceed that of the natural areas. 展开更多
关键词 NDVI spatio-temporal dynamics linear regression method mining activities opencast coal mining areas reclamation areas Jungar Banner
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Love Dynamical Models with Delay
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作者 Kaori Saito Shiho Takagi Yoshihiro Hamaya 《Advances in Pure Mathematics》 2020年第5期297-311,共15页
A sufficient condition for the asymptotic stability of the equilibrium point of a system, which appears as a model for couple of the love affair with time delay, is obtained by applying the technique of linearized met... A sufficient condition for the asymptotic stability of the equilibrium point of a system, which appears as a model for couple of the love affair with time delay, is obtained by applying the technique of linearized method and Hopf- bifurcation. 展开更多
关键词 LOVE AFFAIRS ASYMPTOTIC Stability linearized method Hop-Bifurcation DELAY dynamicAL Model
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An efficient technique for recovering responses of parameterized structural dynamic problems
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作者 Zheng Zhang Xu Han Chao Jiang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期757-766,共10页
In this article,an effective technique is developed to efficiently obtain the output responses of parameterized structural dynamic problems.This technique is based on the conception of reduced basis method and the usa... In this article,an effective technique is developed to efficiently obtain the output responses of parameterized structural dynamic problems.This technique is based on the conception of reduced basis method and the usage of linear interpolation principle.The original problem is projected onto the reduced basis space by linear interpolation projection,and subsequently an associated interpolation matrix is generated.To ensure the largest nonsingularity,the interpolation matrix needs to go through a timenode choosing process,which is developed by applying the angle of vector spaces.As a part of this technique,error estimation is recommended for achieving the computational error bound.To ensure the successful performance of this technique,the offline-online computational procedures are conducted in practical engineering.Two numerical examples demonstrate the accuracy and efficiency of the presented method. 展开更多
关键词 技术开发 参数结构 动态问题 反应 插值原理 线性插值 向量空间 动力学问题
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金融资产泡沫的理论机制与检测方法:文献综述和研究展望
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作者 罗晶 李豪俊 王思佳 《征信》 北大核心 2023年第4期9-15,共7页
金融资产泡沫的形成与破灭,对宏观经济、金融安全造成严重冲击,如应对不当,极易酿成大规模的经济金融危机。对金融资产泡沫的形成、爆发和破灭的理论机制与实证检验进行研究,为我国经济运行守住不发生系统性风险的底线并提供良性运转的... 金融资产泡沫的形成与破灭,对宏观经济、金融安全造成严重冲击,如应对不当,极易酿成大规模的经济金融危机。对金融资产泡沫的形成、爆发和破灭的理论机制与实证检验进行研究,为我国经济运行守住不发生系统性风险的底线并提供良性运转的金融环境具有重大意义。40多年来,国内外相关代表研究主要聚焦于理性预期下和非理性预期下金融资产泡沫的理论机制、金融资产泡沫的线性检验与非线性检验。今后,在金融资产泡沫检验技术、各类金融资产泡沫的溢出、金融资产泡沫识别与资产管理的交叉研究等方面仍有较大的空间。 展开更多
关键词 金融资产泡沫 理论机制 理性预期 检测方法 线性检验 非线性检验 泡沫检验
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考虑土结相互作用下核电厂海域沉管隧道三维抗震分析
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作者 赵杰 甘长江 兰雯竣 《核科学与工程》 CAS CSCD 北大核心 2023年第2期402-411,共10页
为研究核电厂海域安全级取水沉管隧道的动力响应规律,综合考虑结构-土体的相互作用、复杂土体参数的非线性、沉管内部动水的对流效应和脉冲效应,建立了复杂土质地基条件下沉管-土体三维精细化有限元模型,并运用UPFs二次开发在ANSYS中创... 为研究核电厂海域安全级取水沉管隧道的动力响应规律,综合考虑结构-土体的相互作用、复杂土体参数的非线性、沉管内部动水的对流效应和脉冲效应,建立了复杂土质地基条件下沉管-土体三维精细化有限元模型,并运用UPFs二次开发在ANSYS中创建了等价线性单元及黏弹性人工边界,在此基础上开展了极限地震作用下的沉管隧道动力时程分析。计算结果表明:层间位移角符合规范;顶板和底板以受弯为主,其中顶板3的弯矩最大,底板2的剪力最大;三个竖墙以受压为主。其中,中隔墙轴力最大;沉管隧道各墙连接部位内力较大,受地震影响最大。应提高顶底板的抗弯能力及竖墙的抗压能力,适当加固各墙连接部位,同时反应位移法、线弹性动力时程分析法、等价线性分析法三种方法计算出的内力规律基本一致,且等价线性法结果较为合理,反应位移法内力值较为保守。 展开更多
关键词 地震响应 等价线性 动力时程分析 反应位移法 黏弹性边界
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