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Complex variable solution for boundary value problem with X-shaped cavity in plane elasticity and its application* 被引量:3
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作者 Hang ZHOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第9期1329-1346,共18页
A new type of displacement pile, the X-section cast-in-place concrete (XCC) pile, has recently been developed in China. Extensive field tests and laboratory experi- ments are undertaken to evaluate its performance a... A new type of displacement pile, the X-section cast-in-place concrete (XCC) pile, has recently been developed in China. Extensive field tests and laboratory experi- ments are undertaken to evaluate its performance and quantify the non-uniform deforma- tion effect (NUDE) of the X-shaped cross section during installation. This paper develops a simplified theoretical model that attempts to capture the NUDE. Based on the theory of complex variable plane elasticity, closed-form solutions of the stress and displacement for the X-shaped cavity boundary value problem are given. Subsequently, the analytical solution is used to evaluate the NUDE, the concrete filling index (CFI), and the perimeter reduction coefficient of the XCC pile cross section. The computed results are compared with field test results, showing reasonable agreement. The present simplified theoretical model reveals the deformation mechanism of the X-shaped cavity and facilitates applica- tion of the newly developed XCC pile technique in geotechnical engineering. 展开更多
关键词 complex variable solution boundary value problem plane elasticity X-section cast-in-place concrete (XCC) pile deformation mechanism theoretical study
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A SPECIAL METHOD OF FOURIER SERIES WHICH IS EQUAL TO THE METHOD OF SEPARATION OF VARIABLES ON BOUNDARY VALUE PROBLEM
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作者 Yan Xianggan Wu Jike, Department of Mechanics, Peking Unirersity, Bejing 100871. China 《Acta Mechanica Solida Sinica》 SCIE EI 1997年第3期255-261,共7页
By the separation of singularity, a special Fourier series solution of the boundary value problem for plane is obtained, which can satisfy all boundary conditions and converges rapidly. II is proved that the solution ... By the separation of singularity, a special Fourier series solution of the boundary value problem for plane is obtained, which can satisfy all boundary conditions and converges rapidly. II is proved that the solution is equal to the result of separation of variables. As a result, the non-linear characteristic equations resulting from the method of separation of variables are transformed into polynomial equations that can provide a foundation for approximate computation and asymptotic analysis. 展开更多
关键词 separation of singularity series resolution method of separation of variables boundary value problem characteristic equation
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Dirichlet boundary value problem with variable growth
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作者 董增福 付永强 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期262-266,共5页
In this paper, we study higher order elliptic partial differential equations with variable growth, and obtain the existence of solutions in the setting of Wm,p(x) spaces by means of an abstract result for variationa... In this paper, we study higher order elliptic partial differential equations with variable growth, and obtain the existence of solutions in the setting of Wm,p(x) spaces by means of an abstract result for variational inequalities obtained by Gossez and Mustonen. Our result generalizes the corresponding one of Kováik and Rákosník. 展开更多
关键词 boundary value problem elliptic partial differential equation variable growth
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On the Strong Law of Large Numbers for Non-Independent B-Valued Random Variables
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作者 Gan Shi-xin 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第1期13-17,共5页
This paper investigates some conditions which imply the strong laws of large numbers for Bana ch space val-ued random variable sequences.Some generalizations of the Marcinkiewicz-Zygmund theorem and the Hoffmann-Jdprg... This paper investigates some conditions which imply the strong laws of large numbers for Bana ch space val-ued random variable sequences.Some generalizations of the Marcinkiewicz-Zygmund theorem and the Hoffmann-Jdprgensen and Pisier theorem are obtained. 展开更多
关键词 strong law of large numbers Banach space valued random variable sequence p-smoothable Banach space
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A Strong Law of Large Numbers for Set-Valued Random Variables in Gα Space
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作者 Guan Li 《Journal of Applied Mathematics and Physics》 2015年第7期797-801,共5页
In this paper, we shall represent a strong law of large numbers (SLLN) for weighted sums of set- valued random variables in the sense of the Hausdorff metric dH, based on the result of single-valued random variable ob... In this paper, we shall represent a strong law of large numbers (SLLN) for weighted sums of set- valued random variables in the sense of the Hausdorff metric dH, based on the result of single-valued random variable obtained by Taylor [1]. 展开更多
关键词 SET-valueD RANDOM variable the LAWS of Large NUMBERS HAUSDORFF METRIC
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Strong Laws of Large Numbers for Fuzzy Set-Valued Random Variables in Gα Space
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作者 Lamei Shen Li Guan 《Advances in Pure Mathematics》 2016年第9期583-592,共10页
In this paper, we shall present the strong laws of large numbers for fuzzy set-valued random variables in the sense of d<sup>&infin;</sup><sub>H</sub> . The results are based on the result ... In this paper, we shall present the strong laws of large numbers for fuzzy set-valued random variables in the sense of d<sup>&infin;</sup><sub>H</sub> . The results are based on the result of single-valued random variables obtained by Taylor [1] and set-valued random variables obtained by Li Guan [2]. 展开更多
关键词 Laws of Large Numbers Fuzzy Set-valued Random variable Hausdorff Metric
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线性Errors-in-Variables模型在确定汶川地震主震断层面中的应用 被引量:7
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作者 王福昌 曹慧荣 万永革 《数理统计与管理》 CSSCI 北大核心 2010年第3期381-390,共10页
首先介绍线性Errors-in-Variables模型,给出求解回归系数的奇异值分解(SVD)算法和MATLAB源代码,其次指出在模型中所有变量均具有不可忽略的误差时,全最小二乘法得到回归系数估计更接近于模型中的真实系数,并通过理论分析和计算机仿真说... 首先介绍线性Errors-in-Variables模型,给出求解回归系数的奇异值分解(SVD)算法和MATLAB源代码,其次指出在模型中所有变量均具有不可忽略的误差时,全最小二乘法得到回归系数估计更接近于模型中的真实系数,并通过理论分析和计算机仿真说明了这一结果,最后将线性模型和算法用于确定汶川大地震主震断层面,取得了与震源机制解一致的结果,说明了模型和算法的有效性。 展开更多
关键词 线性Errors-in-variables模型 奇异值分解 断层面参数 汶川余震
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NONLINEAR RIEMANN AND HILBERT BOUNDARY VALUE PROBLEMS WITH SQUARE ROOTS IN VARIABLE EXPONENT SPACES
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作者 Yajun Hu Fuli He 《Acta Mathematica Scientia》 2026年第1期1-18,共18页
In this paper,we study the nonlinear Riemann boundary value problem with square roots that is represented by a Cauchy-type integral with kernel density in variable exponent Lebesgue spaces.We discuss the odd-order zer... In this paper,we study the nonlinear Riemann boundary value problem with square roots that is represented by a Cauchy-type integral with kernel density in variable exponent Lebesgue spaces.We discuss the odd-order zero-points distribution of the solutions and separate the single valued analytic branch of the solutions with square roots,then convert the problem to a Riemann boundary value problem in variable exponent Lebesgue spaces and discuss the singularity of solutions at individual zeros belonging to curve.We consider two types of cases those where the coefficient is Hölder and those where it is piecewise Hölder.Then we solve the Hilbert boundary value problem with square roots in variable exponent Lebesgue spaces.By discussing the distribution of the odd-order zero-points for solutions and the method of symmetric extension,we convert the Hilbert problem to a Riemann boundary value problem.The equivalence of the transformation is discussed.Finally,we get the solvable conditions and the direct expressions of the solutions in variable exponent Lebesgue spaces. 展开更多
关键词 boundary value problem Cauchy-type integral variable exponent spaces non-linearity piecewise Lyapunov curve
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Analysis of heart rate variability based on singular value decomposition entropy 被引量:2
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作者 李世阳 杨明 +1 位作者 李存岑 蔡萍 《Journal of Shanghai University(English Edition)》 CAS 2008年第5期433-437,共5页
Assessing the dynamics of heart rate fluctuations can provide valuable information about heart status. In this study, regularity of heart rate variability (HRV) of heart failure patients and healthy persons using th... Assessing the dynamics of heart rate fluctuations can provide valuable information about heart status. In this study, regularity of heart rate variability (HRV) of heart failure patients and healthy persons using the concept of singular value decomposition entropy (SvdEn) is analyzed. SvdEn is calculated from the time series using normalized singular values. The advantage of this method is its simplicity and fast computation. It enables analysis of very short and non-stationary data sets. The results show that SvdEn of patients with congestive heart failure (CHF) shows a low value (SvdEn: 0.056±0.006, p 〈 0.01) which can be completely separated from healthy subjects. In addition, differences of SvdEn values between day and night are found for the healthy groups. SvdEn decreases with age. The lower the SvdEn values, the higher the risk of heart disease. Moreover, SvdEn is associated with the energy of heart rhythm. The results show that using SvdEn for discriminating HRV in different physiological states for clinical applications is feasible and simple. 展开更多
关键词 heart rate variability (HRV) singular value decomposition (SVD) ENTROPY congestive heart failure (CHF)
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Multilinear Calderón-Zygmund Operators and Their Commutators with BMO Functions in Herz-Morrey Spaces with Variable Smoothness and Integrability 被引量:1
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作者 hu yuan-zhu xu jing-shi ji you-qing 《Communications in Mathematical Research》 CSCD 2017年第3期238-258,共21页
In this paper, we obtain that multilinear Calderón-Zygmund operators and their commutators with BMO functions are bounded on products of Herz-Morrey spaces with variable smoothness and integrability. The vector-v... In this paper, we obtain that multilinear Calderón-Zygmund operators and their commutators with BMO functions are bounded on products of Herz-Morrey spaces with variable smoothness and integrability. The vector-valued setting of multilinear Calderón-Zygmund operators is also considered. 展开更多
关键词 multilinear Calderón-Zygmund operator variable exponent Herz-Morrey space vector valued estimate
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A Path Integral Generalization of Bell Local Hidden Variable Models for Unstable Particles 被引量:2
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作者 Gianpaolo Bei 《Journal of Applied Mathematics and Physics》 2021年第10期2430-2438,共9页
We discuss the problem of the generalization of Bell local hidden variable models for unstable particles as nucleons or decaying quantum bound states. We propose to extend the formalism of real deterministic hidden va... We discuss the problem of the generalization of Bell local hidden variable models for unstable particles as nucleons or decaying quantum bound states. We propose to extend the formalism of real deterministic hidden variables in the complex domain, in analogy with the quantum Gamow ket formalism, and we introduce a time dependent classical probability density distribution by which we implement hidden time dependence in the quantum expectation values. We suggest therefore a classical framework which may recover by asymptotic temporal limits the standard Bell stationary quantum statistical averages. Endly we discuss the possible relevance of our proposal for general non-isolated quantum systems in noninertial frames and the consequent dynamic effects of vacuum instabilities on E.P.R tests and Q.M. ensemble statistical averages. 展开更多
关键词 Entangled Unstable Particles Complex Hidden variables Path Dependent Expectation values Time Dependent Bell Inequalities
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Linguistic Truth Values Lattice Implication Algebras
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作者 潘小东 徐扬 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期101-104,109,共5页
In order to study uncertainty reasoning and automatic reasoning with linguistic terms, in this paper, the set of basic linguistic truth values and the set of modifiers are defined, according to common sense; partially... In order to study uncertainty reasoning and automatic reasoning with linguistic terms, in this paper, the set of basic linguistic truth values and the set of modifiers are defined, according to common sense; partially orderings are defined on them. Based on it, a lattice implication algebra model L18 of linguistic terms is built; furthermore, its some basic properties are discussed. 展开更多
关键词 linguistic truth value linguistic variable computing with words lattice implication algebra Subalgebra.
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Mean Square Numerical Methods for Initial Value Random Differential Equations
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作者 Magdy A. El-Tawil Mohammed A. Sohaly 《Open Journal of Discrete Mathematics》 2011年第2期66-84,共19页
In this paper, the random Euler and random Runge-Kutta of the second order methods are used in solving random differential initial value problems of first order. The conditions of the mean square convergence of the nu... In this paper, the random Euler and random Runge-Kutta of the second order methods are used in solving random differential initial value problems of first order. The conditions of the mean square convergence of the numerical solutions are studied. The statistical properties of the numerical solutions are computed through numerical case studies. 展开更多
关键词 RANDOM Differential Equations Mean SQUARE SENSE Second RANDOM variable Initial value Problems RANDOM EULER METHOD RANDOM Runge Kutta-2 METHOD
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Variable Screening of Neural Network based on MIV
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作者 Guxiong Li KaiHuang 《International Journal of Technology Management》 2014年第12期131-134,共4页
Screening variables with significant features as the input data of network, is an important step in application of neural network to predict and analysis problems. This paper proposed a method using MIV algorithm to s... Screening variables with significant features as the input data of network, is an important step in application of neural network to predict and analysis problems. This paper proposed a method using MIV algorithm to screen variables of BP neural network.And experimental results show that, the proposed technique is practical and reliable. 展开更多
关键词 variable screening mean impact value BP neural network
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A Radial Basis Function Method with Improved Accuracy for Fourth Order Boundary Value Problems
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作者 Scott A. Sarra Derek Musgrave +1 位作者 Marcus Stone Joseph I. Powell 《Journal of Applied Mathematics and Physics》 2024年第7期2559-2573,共15页
Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with... Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with Radial Basis Function methods. The method is used to solve fourth order boundary value problems. The use and location of ghost points are examined in order to enforce the extra boundary conditions that are necessary to make a fourth-order problem well posed. The use of ghost points versus solving an overdetermined linear system via least squares is studied. For a general fourth-order boundary value problem, the recommended approach is to either use one of two novel sets of ghost centers introduced here or else to use a least squares approach. When using either ghost centers or least squares, the random variable shape parameter strategy results in significantly better accuracy than when a constant shape parameter is used. 展开更多
关键词 Numerical Partial Differential Equations Boundary value Problems Radial Basis Function Methods Ghost Points variable Shape Parameter Least Squares
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Practice of Simple Variable Expressions
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作者 庄卓慧 《疯狂英语(双语世界)》 2024年第4期42-46,55,共6页
Ⅰ.Evaluate variable expressions.1.Find the value of the expression“4×v”,for v=3.2.Find the value of the expression“10÷u”,for u=2.3.Find the value of the expression“20-z”,for z=7.
关键词 value EXPRESSIONS variable
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Revisiting Capacity Value of Variable Renewable Energy Generation in Power Systems with High Renewable Energy Penetration
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作者 Yanghao Yu Haiyang Jiang +5 位作者 Ning Zhang Pei Yong Fei Teng Jiawei Zhang Yating Wang Goran Strbac 《Journal of Modern Power Systems and Clean Energy》 2025年第5期1593-1603,共11页
Adequacy is a key concern of power system planning,which refers to the availability of sufficient facilities to meet demand.The capacity value(CV)of variable renewable energy(VRE)generation represents its equivalent c... Adequacy is a key concern of power system planning,which refers to the availability of sufficient facilities to meet demand.The capacity value(CV)of variable renewable energy(VRE)generation represents its equivalent contribution to system adequacy,in comparison to conventional generators.While VRE continues to grow and increasingly dominates the generation portfolio,its CV is becoming non-negligible,with the corresponding impact mechanisms becoming more complicated and nuanced.In this paper,the concept of CV is revisited by analyzing how VRE contributes to power system balancing at a high renewable energy penetration level.A generalized loss function is incorporated into the CV evaluation framework considering the adequacy of the power system.An analytical method for the CV evaluation of VRE is then derived using the statistical properties of both hourly load and VRE generation.Through the explicit CV expression,several critical impact factors,including the VRE generation variance,source-load correlation,and system adequacy level,are identified and discussed.Case studies demonstrate the accuracy and effectiveness of the proposed method in comparison to the traditional capacity factor-based methods and convolution-based methods.In the IEEERTS79 test system,the CV of a 2500 MW wind farm(with40%renewable energy penetration level)is found to be 6.8%of its nameplate capacity.Additionally,the sensitivity of CV to various impact factors in power systems with high renewable energy penetration is analyzed. 展开更多
关键词 Power system planning capacity value(CV) equivalent firm capacity variable renewable energy(VRE)generation system adequacy
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基于改进FRAM的航班地面保障能力评估
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作者 邢志伟 李雅婷 +2 位作者 周芳宇 张涛 罗谦 《计算机测量与控制》 2026年第2期266-274,共9页
针对机场和航空公司运行效率低下,决策能力不足的问题,提出了一种基于功能共振分析模型的航班地面保障能力评估方法;通过对航班保障流程进行分析,利用区间值犹豫模糊熵和层次分析法将保障环节之间的关系量化,结合保障环节的大小、可变... 针对机场和航空公司运行效率低下,决策能力不足的问题,提出了一种基于功能共振分析模型的航班地面保障能力评估方法;通过对航班保障流程进行分析,利用区间值犹豫模糊熵和层次分析法将保障环节之间的关系量化,结合保障环节的大小、可变性以及环节之间的耦合得到航班保障能力评估结果,从而确定该航班地面保障节点最优构型;使用某机场航班地面保障数据进行实验仿真,结果表明:实际运行与期望之间存在的均方误差为6.015 min,平均绝对误差为2.389 min,误差与保障时间窗之比约为0.28,与该航班的效能评估值近似相加为1,反映出实际与期望之间的差距;此外改变权重方法对比分析,航班保障关键节点的平均绝对百分误差均低于13%,且均比熵权法的值低。 展开更多
关键词 航班保障 能力评估 功能共振模型 区间值犹豫模糊熵 层次分析 环节耦合 可变性
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柔性变翼尖飞行器横航向鲁棒变增益控制
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作者 胡芳芳 雷鹏轩 《飞行力学》 北大核心 2026年第1期26-31,39,共7页
针对柔性变翼尖布局变体飞行器的飞行控制问题,分析了翼尖柔性变形对横航向动力学特性的影响规律,将翼尖上反角作为衡量变形的参数,通过CFD仿真获得了横航向静稳定性导数随广义位移的变化特性。进一步通过高阶奇异值分解方法实现了对非... 针对柔性变翼尖布局变体飞行器的飞行控制问题,分析了翼尖柔性变形对横航向动力学特性的影响规律,将翼尖上反角作为衡量变形的参数,通过CFD仿真获得了横航向静稳定性导数随广义位移的变化特性。进一步通过高阶奇异值分解方法实现了对非线性模型的全局线性化,并建立了线性变参数(LPV)多胞型模型,设计了一种适用于多胞型系统、对结构变化和外界扰动具有鲁棒性的参数依赖状态反馈控制器,克服了两次Lyapunov稳定思想依赖同一个Lyapunov函数的弊端。研究表明,提出的控制器可以实现不同构型下变体飞行器的稳定飞行和协调转弯控制,且对模型不确定性和外界扰动具有一定的鲁棒性。 展开更多
关键词 飞行控制 柔性变翼尖 高阶奇异值分解 参数依赖 鲁棒变增益控制
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术后24 h内动态心电图心率变异性指标联合检测对NSTEMI患者PCI术后6个月内MACE的预测价值
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作者 王艳玲 王彦 +1 位作者 郭春宏 李林 《海南医学》 2026年第5期657-662,共6页
目的探讨经皮冠状动脉介入(PCI)术后24 h内动态心电图心率变异性指标[正常窦性心搏间期标准差(SDNN)、NN间期平均值标准差(SDANN)、相邻正常窦性心搏间期差值的均方根(RMSSD)、相邻NN间期差异≥50 ms的心搏占该时间段内总心搏个数的百分... 目的探讨经皮冠状动脉介入(PCI)术后24 h内动态心电图心率变异性指标[正常窦性心搏间期标准差(SDNN)、NN间期平均值标准差(SDANN)、相邻正常窦性心搏间期差值的均方根(RMSSD)、相邻NN间期差异≥50 ms的心搏占该时间段内总心搏个数的百分比(PNN50)、三角指数及心率减速力(DC)]联合检测对非ST段抬高型心肌梗死(NSTEMI)患者PCI术后6个月主要不良心血管事件(MACE)发生的预测价值。方法回顾性选取2020年12月至2024年12月河南省荣军医院(河南省荣军休养院)收治的350例NSTEMI患者,均行PCI术治疗,PCI术前和术后24 h内检测动态心电图心率变异性指标SDNN、SDANN、RMSSD、PNN50、DC。根据PCI术后6个月内有无MACE发生分为发生组(n=61)与未发生组(n=289),比较两组PCI术前和术后24 h内动态心电图心率变异性指标;采用平滑曲线拟合分析PCI术后24 h内动态心电图心率变异性指标与PCI术后6个月发生MACE的相关性,二元Logistic回归分析获取SDNN、SDANN、RMSSD、PNN50、DC指标联合检测概率值后,采用受试者工作特征(ROC)曲线分析PCI术后24 h内动态心电图心率变异性指标对NSTEMI患者PCI术后6个月发生MACE的预测价值。结果发生组PCI术后24 h内动态心电图心率变异性指标SDNN、SDANN、RMSSD、PNN50、DC分别为(90.42±19.85)ms、(84.63±16.02)ms、(19.35±4.88)ms、(5.03±1.24)%、(4.52±1.04)ms,明显低于未发生组的(105.69±24.31)ms、(98.42±19.36)ms、(25.69±6.04)ms、(5.92±1.14)%、(5.59±1.21)ms,差异均有统计学意义(P<0.05);平滑曲线拟合分析显示,NSTEMI患者PCI术后24 h内动态心电图心率变异性指标SDNN、SDANN、RMSSD、PNN50、DC与PCI术后6个月发生MACE风险呈负相关(P<0.05);二元Logistic回归分析构建SDNN、SDANN、RMSSD、PNN50、DC联合预测模型,获取预测概率值Logit(p)=-0.423+0.152×SDNN+0.213×SDANN+0.178×RMSSD+0.119×PNN50+0.224×DC;ROC曲线证实,PCI术后24 h内动态心电图心率变异性指标SDNN、SDANN、RMSSD、PNN50、DC联合预测NSTEMI患者PCI术后6个月发生MACE的AUC为0.894,高于上述动态心电图心率变异性指标单独检测的0.757、0.749、0.776、0.737、0.774(P<0.05)。结论PCI术后24 h内动态心电图心率变异性相关指标与NSTEMI患者PCI术后6个月内MACE的发生密切相关,PCI术后24 h内动态心电图心率变异性相关指标联合检测对NSTEMI患者PCI术后6个月内发生MACE具有较高的预测效能,临床可通过早期检测动态心电图心率变异性评估NSTEMI患者PCI术后6个月内MACE发生风险。 展开更多
关键词 非ST段抬高型心肌梗死 经皮冠状动脉介入 主要不良心血管事件 动态心电图 心率变异性 预测价值
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