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Some inequalities for the generalized linear distortion function 被引量:2
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作者 MA Xiao-yan QIU Song-liang +1 位作者 ZHONG Gen-hong CHU Yu-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第1期87-93,共7页
In this paper, we establish several inequalities for the the generalized linear distortion function λ(a, K) by using the monotonicity and convexity of certain combinations λ(a, K).
关键词 modular equation generalized linear distortion function inequality.
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A New Definition for Generalized First Derivative of Nonsmooth Functions 被引量:1
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作者 Ali Vahidian Kamyad Mohammad Hadi Noori Skandari Hamid Reza Erfanian 《Applied Mathematics》 2011年第10期1252-1257,共6页
In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are ap... In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are applied for non-smooth functions which by solving these problems we obtain a kind of generalized first derivatives. For this purpose, a linear programming problem corresponding functional optimization problem is obtained which their optimal solutions give the approximate generalized first derivative. We show the efficiency of our approach by obtaining derivative and generalized derivative of some smooth and nonsmooth functions respectively in some illustrative examples. 展开更多
关键词 generalized DERIVATIVE SMOOTH and NONSMOOTH functionS FOURIER analysis linear PROGRAMMING functional Optimization
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A New Conjugate Gradient Projection Method for Solving Stochastic Generalized Linear Complementarity Problems 被引量:2
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作者 Zhimin Liu Shouqiang Du Ruiying Wang 《Journal of Applied Mathematics and Physics》 2016年第6期1024-1031,共8页
In this paper, a class of the stochastic generalized linear complementarity problems with finitely many elements is proposed for the first time. Based on the Fischer-Burmeister function, a new conjugate gradient proje... In this paper, a class of the stochastic generalized linear complementarity problems with finitely many elements is proposed for the first time. Based on the Fischer-Burmeister function, a new conjugate gradient projection method is given for solving the stochastic generalized linear complementarity problems. The global convergence of the conjugate gradient projection method is proved and the related numerical results are also reported. 展开更多
关键词 Stochastic generalized linear Complementarity Problems Fischer-Burmeister function Conjugate Gradient Projection Method Global Convergence
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Empirical Likelihood Inference for Generalized Partially Linear Models with Longitudinal Data
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作者 Jinghua Zhang Liugen Xue 《Open Journal of Statistics》 2020年第2期188-202,共15页
In this article, we propose a generalized empirical likelihood inference for the parametric component in semiparametric generalized partially linear models with longitudinal data. Based on the extended score vector, a... In this article, we propose a generalized empirical likelihood inference for the parametric component in semiparametric generalized partially linear models with longitudinal data. Based on the extended score vector, a generalized empirical likelihood ratios function is defined, which integrates the within-cluster?correlation meanwhile avoids direct estimating the nuisance parameters in the correlation matrix. We show that the proposed statistics are asymptotically?Chi-squared under some suitable conditions, and hence it can be used to construct the confidence region of parameters. In addition, the maximum empirical likelihood estimates of parameters and the corresponding asymptotic normality are obtained. Simulation studies demonstrate the performance of the proposed method. 展开更多
关键词 Longitudinal Data generalized PARTIALLY linear Models Empirical LIKELIHOOD QUADRATIC INFERENCE function
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On Generalized High Order Derivatives of Nonsmooth Functions
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作者 Samaneh Soradi Zeid Ali Vahidian Kamyad 《American Journal of Computational Mathematics》 2014年第4期317-328,共12页
In this paper, we proposed a Extension Definition to derive, simultaneously, the first, second and high order generalized derivatives for non-smooth functions, in which the involved functions are Riemann integrable bu... In this paper, we proposed a Extension Definition to derive, simultaneously, the first, second and high order generalized derivatives for non-smooth functions, in which the involved functions are Riemann integrable but not necessarily locally Lipschitz or continuous. Indeed, we define a functional optimization problem corresponding to smooth functions where its optimal solutions are the first and second derivatives of these functions in a domain. Then by applying these functional optimization problems for non-smooth functions and using this method we obtain generalized first derivative (GFD) and generalized second derivative (GSD). Here, the optimization problem is approximated with a linear programming problem that by solving of which, we can obtain these derivatives, as simple as possible. We extend this approach for obtaining generalized high order derivatives (GHODs) of non-smooth functions, simultaneously. Finally, for efficiency of our approach some numerical examples have been presented. 展开更多
关键词 generalized DERIVATIVE SMOOTH and NONSMOOTH functions NONSMOOTH Optimization Problem linear PROGRAMMING
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Approximate derivative-dependent functional variable separation for quasi-linear diffusion equations with a weak source
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作者 吉飞宇 杨春晓 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期67-72,共6页
By using the approximate derivative-dependent functional variable separation approach, we study the quasi-linear diffusion equations with a weak source ut = (A(u)Ux)x + eB(u, Ux). A complete classification of t... By using the approximate derivative-dependent functional variable separation approach, we study the quasi-linear diffusion equations with a weak source ut = (A(u)Ux)x + eB(u, Ux). A complete classification of these perturbed equations which admit approximate derivative-dependent functional separable solutions is listed. As a consequence, some approxi- mate solutions to the resulting perturbed equations are constructed via examples. 展开更多
关键词 quasi-linear diffusion equation approximate derivative-dependent functional separable solution approximate generalized conditional symmetry
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Research on Grid-Connected Control Strategy of Distributed Generator Based on Improved Linear Active Disturbance Rejection Control 被引量:1
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作者 Xin Mao Hongsheng Su Jingxiu Li 《Energy Engineering》 EI 2024年第12期3929-3951,共23页
The virtual synchronous generator(VSG)technology has been proposed to address the problem of system frequency and active power oscillation caused by grid-connected new energy power sources.However,the traditional volt... The virtual synchronous generator(VSG)technology has been proposed to address the problem of system frequency and active power oscillation caused by grid-connected new energy power sources.However,the traditional voltage-current double-closed-loop control used in VSG has the disadvantages of poor disturbance immunity and insufficient dynamic response.In light of the issues above,a virtual synchronous generator voltage outer-loop control strategy based on improved linear autonomous disturbance rejection control(ILADRC)is put forth for consideration.Firstly,an improved first-order linear self-immunity control structure is established for the characteristics of the voltage outer loop;then,the effects of two key control parameters-observer bandwidthω_(0)and controller bandwidthω_(c)on the control system are analyzed,and the key parameters of ILADRC are optimally tuned online using improved gray wolf optimizer-radial basis function(IGWO-RBF)neural network.A simulationmodel is developed using MATLAB to simulate,analyze,and compare the method introduced in this paper.Simulations are performed with the traditional control strategy for comparison,and the results demonstrate that the proposed control method offers superior anti-interference performance.It effectively addresses power and frequency oscillation issues and enhances the stability of the VSG during grid-connected operation. 展开更多
关键词 Virtual synchronous generator(VSG) active power improved linear active disturbance rejection control(ILADRC) radial basis function(RBF)neural networks improved gray wolf optimizer(IGWO)
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A New General Linear Convolution Model for fMRI Data Process 被引量:1
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作者 袁宏 陈华富 尧德中 《Journal of Electronic Science and Technology of China》 2005年第1期68-71,共4页
General linear model (GLM) is the most popular method for functional magnetic resource imaging (fMRI) data analysis . However, its theory is imperfect. The key of this model is how to constitute the design-matrix to m... General linear model (GLM) is the most popular method for functional magnetic resource imaging (fMRI) data analysis . However, its theory is imperfect. The key of this model is how to constitute the design-matrix to model the interesting effects better and separate noises better. For the purpose of detecting brain function activation , according to the principle of GLM,a new convolution model is presented by a new dynamic function convolving with design-matrix,which combining with t-test can be used to detect brain active signal. The fMRI imaging result of visual stimulus experiment indicates that brain activities mainly concentrate among v1and v2 areas of visual cortex, and also verified the validity of this technique. 展开更多
关键词 FMRI general linear model T-TEST hemodynamic response function
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A New Vector-Valued Padé-Type Approximation in the Inner Space
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作者 Chunjing Li 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第2期127-136,共10页
A new vector-valued Pad′e-type approximation is defined by introducing a gener- alized vector-valued linear functional from a scalar polynomial space to a vector space. Some algebraic properties and error formulas ar... A new vector-valued Pad′e-type approximation is defined by introducing a gener- alized vector-valued linear functional from a scalar polynomial space to a vector space. Some algebraic properties and error formulas are presented. The expressions of this Pad′e-type ap- proximants are provided with the generating function form and the determinant form. 展开更多
关键词 逼近 内部空间 标量多项式空间 向量估计
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男性人群糖尿病和肺功能的相关性研究
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作者 宋路 兰志刚 +4 位作者 周葳 冯丽萍 刘运秋 陈朔华 王丽晔 《中国全科医学》 北大核心 2026年第12期1572-1578,1587,共8页
背景目前全球糖尿病患者已达5.37亿,我国糖尿病患者人数最多,越来越多的研究发现肺脏也是糖尿病的靶器官。既往关于糖尿病与肺功能的横断面研究结论基本一致:与非糖尿病人群相比,糖尿病人群的肺功能更低。然而,对于糖尿病和肺功能下降... 背景目前全球糖尿病患者已达5.37亿,我国糖尿病患者人数最多,越来越多的研究发现肺脏也是糖尿病的靶器官。既往关于糖尿病与肺功能的横断面研究结论基本一致:与非糖尿病人群相比,糖尿病人群的肺功能更低。然而,对于糖尿病和肺功能下降速度的纵向研究较少,且目前研究结论并不一致。目的探讨男性人群糖尿病和肺功能的相关性。方法选取2014—2020年参加包括肺功能检查在内的开滦健康体检的男性开滦职工为研究对象,最终纳入18438例(其中完成第2次肺功能检查的为12448例)。根据观察对象的血糖水平分为3组:空腹血糖(FPG)正常组(FPG<6.1 mmol/L)15727例、空腹血糖受损(IFG)组(6.1 mmol/L≤FPG<7.0 mmol/L)1490例、糖尿病组(FPG≥7.0 mmol/L或有糖尿病史或正在服用降糖药)1221例。采用广义线性模型分析不同血糖水平与肺功能指标[用力肺活量占预计值百分比(FVC%pred)、第1秒用力呼气容积占预计值百分比(FEV_(1)%pred)、最大呼气中期流量占预计值百分比(MMEF%pred)、第1秒用力呼气容积与用力肺活量比值(FEV_(1)/FVC)]及相关肺功能指标下降速度的关联。结果18438例研究对象的平均年龄为(42.90±9.73)岁。糖尿病组FVC%pred、FEV_(1)%pred水平低于FPG正常组和IFG组,IFG组MMEF%pred水平高于FPG正常组和糖尿病组(P<0.05);3组研究对象肺功能下降速度比较,差异均无统计学意义(P>0.05)。校正相关变量后,广义线性模型分析结果显示(以FPG正常组为参照),糖尿病与FVC%pred(B=-1.000,95%CI=-1.784~-0.218,P=0.012)、FEV_(1)%pred(B=-1.266,95%CI=-2.236~-0.296,P=0.011)均呈负相关,与MMEF%pred、FEV_(1)/FVC无相关性(P>0.05);IFG、糖尿病与肺功能指标下降速度均无相关性(P>0.05)。结论糖尿病与男性肺功能指标(FVC%pred、FEV_(1)%pred)呈负向关联,但是未发现糖尿病与男性肺功能指标下降速度有关。 展开更多
关键词 糖尿病 肺功能 男性 空腹血糖受损 广义线性模型分析 唐山市
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DDPG优化算法的改进型自抗扰风电机组桨距角控制
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作者 徐晓宁 范召强 +3 位作者 周雪松 陶珑 问虎龙 杨风霞 《太阳能学报》 北大核心 2026年第1期575-584,共10页
为解决传统风电机组桨距角控制策略面对风速变化时存在动态响应差以及控制器参数适应性不足导致输出功率波动大的问题,提出一种基于深度确定性策略梯度(DDPG)算法的改进型线性自抗扰桨距角控制策略。该策略在线性扩张状态观测器(LESO)... 为解决传统风电机组桨距角控制策略面对风速变化时存在动态响应差以及控制器参数适应性不足导致输出功率波动大的问题,提出一种基于深度确定性策略梯度(DDPG)算法的改进型线性自抗扰桨距角控制策略。该策略在线性扩张状态观测器(LESO)基础上引入自由扩张维度的状态变量,并对增阶后的参数基于比例微分形式进行改进,以提高对扰动的顺馈矫正能力。随后根据发电机转速误差设计合适的奖励函数,利用DDPG算法使改进后的线性自抗扰控制(LADRC)参数能够自适应调整,实现最优的控制效果。仿真结果表明,所提策略能有效应对风速剧烈波动,使桨距角能快速适应风速变化,从而维持风电机组的稳定运行和电能的高效输出。 展开更多
关键词 风电机组 桨距角 线性自抗扰控制 深度确定性策略梯度 奖励函数 参数整定
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CONNECTION BETWEEN THE ORDER OF FRACTIONAL CALCULUS AND FRACTIONAL DIMENSIONS OF A TYPE OF FRACTAL FUNCTIONS 被引量:7
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作者 Yongshun Liang Weiyi Su 《Analysis in Theory and Applications》 2007年第4期354-362,共9页
The linear relationship between fractal dimensions of a type of generalized Weierstrass functions and the order of their fractional calculus has been proved. The graphs and numerical results given here further indicat... The linear relationship between fractal dimensions of a type of generalized Weierstrass functions and the order of their fractional calculus has been proved. The graphs and numerical results given here further indicate the corresponding relationship. 展开更多
关键词 generalized Weierstrass function Riemann-Liouville fractional calculus fractal dimension linear GRAPH
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ORTHOGONAL POLYNOMIALS AND DETERMINANT FORMULAS OF FUNCTION-VALUED PADE-TYPE APPROXIMATION USING FOR SOLUTION OF INTEGRAL EQUATIONS 被引量:2
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作者 顾传青 潘宝珍 吴蓓蓓 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第6期853-860,共8页
To solve Fredholm integral equations of the second kind, a generalized linear functional is introduced and a new function-valued Padé-type approximation is defined. By means of the power series expansion of the s... To solve Fredholm integral equations of the second kind, a generalized linear functional is introduced and a new function-valued Padé-type approximation is defined. By means of the power series expansion of the solution, this method can construct an approximate solution to solve the given integral equation. On the basis of the orthogonal polynomials, two useful determinant expressions of the numerator polynomial and the denominator polynomial for Padé-type approximation are explicitly given. 展开更多
关键词 generalized linear functional function-valued Padé-type approximation Fredholm integral equation orthogonal polynomial determinant formula
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ESTIMATION METHOD FOR SOLUTIONS TO GENERAL LINEAR SYSTEM OF VOLTERRA INTEGRAL INEQUALITIES INVOLVING ITERATED INTEGRAL FUNCTIONALS 被引量:2
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作者 MA Qinghua (Department of Mathematics, Huizhou University, Huizhou 516015, China) YANG Enhao (Department of Mathematics, Jinan University, Guangzhou 510632, China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 2000年第2期201-207,共7页
An estimation method for solutions to the general linear system of Volterra- type integral inequalities containing several iterated integral functionals is obtained. This method is based on a result proved by the pres... An estimation method for solutions to the general linear system of Volterra- type integral inequalities containing several iterated integral functionals is obtained. This method is based on a result proved by the present second author in Journ. Math. Anal. Appl.(1984). A certain two-dimensional system of nonlinear ordinary differential equations is also discussed to demonstrate the usefulness of our method. 展开更多
关键词 generAL linear system INTEGRAL inequality Volterra-type ITERATED INTEGRAL functional.
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THE REALIZATION OF LINEAR SHIFT-VARIANT FILTERS THROUGH STATE FEEDBACK
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作者 冯志彪 沈永昌 R.Unbehauen 《Journal of Electronics(China)》 1991年第3期259-267,共9页
In this paper a new method to realize rational generalized transfer functions of linearshift-variant digital filters through state feedback is presented In some practical applications therequired characteristics of th... In this paper a new method to realize rational generalized transfer functions of linearshift-variant digital filters through state feedback is presented In some practical applications therequired characteristics of the filter change slowly.Under these circumstances,the proposedmethod is very effective and the resulting filter structure is simple.A numerical example isprovided to show the performance of the method. 展开更多
关键词 linear shift-variant digital filter Shift-variant IMPULSE response generalized transfer function
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Confidence Intervals of Variance Functions in Generalized Linear Model
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作者 Yong Zhou Dao-ji Li 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2006年第3期353-368,共16页
In this paper we introduce an appealing nonparametric method for estimating variance and conditional variance functions in generalized linear models (GLMs), when designs are fixed points and random variables respect... In this paper we introduce an appealing nonparametric method for estimating variance and conditional variance functions in generalized linear models (GLMs), when designs are fixed points and random variables respectively, Bias-corrected confidence bands are proposed for the (conditional) variance by local linear smoothers. Nonparametric techniques are developed in deriving the bias-corrected confidence intervals of the (conditional) variance. The asymptotic distribution of the proposed estimator is established and show that the bias-corrected confidence bands asymptotically have the correct coverage properties. A small simulation is performed when unknown regression parameter is estimated by nonparametric quasi-likelihood. The results are also applicable to nonparamctric autoregressive times series model with heteroscedastic conditional variance. 展开更多
关键词 Nonlinear time series model variance function conditional heteroscedastie variance generalized linear model local polynomial fitting Α-MIXING
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COMPLETE MONOTONICITY FOR A NEW RATIO OF FINITELY MANY GAMMA FUNCTIONS
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作者 Feng QI 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期511-520,共10页
In this paper,by deriving an inequality involving the generating function of the Bernoulli numbers,the author introduces a new ratio of finitely many gamma functions,finds complete monotonicity of the second logarithm... In this paper,by deriving an inequality involving the generating function of the Bernoulli numbers,the author introduces a new ratio of finitely many gamma functions,finds complete monotonicity of the second logarithmic derivative of the ratio,and simply reviews the complete monotonicity of several linear combinations of finitely many digamma or trigamma functions. 展开更多
关键词 Bernoulli number RATIO generating function complete monotonicity gamma function digamma function trigamma function logarithmic derivative linear combination INEQUALITY
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GH_2 Control for Uncertain Discrete-time-delay Fuzzy Systems Based on a Switching Fuzzy Model and Piecewise Lyapunov Function
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作者 Zhi-Le Xia Jun-Min Li 《International Journal of Automation and computing》 EI 2009年第3期261-266,共6页
Generalized H2 (GH2) stability analysis and controller design of the uncertain discrete-time Takagi-Sugeno (T-S) fuzzy systems with state delay are studied based on a switching fuzzy model and piecewise Lyapunov f... Generalized H2 (GH2) stability analysis and controller design of the uncertain discrete-time Takagi-Sugeno (T-S) fuzzy systems with state delay are studied based on a switching fuzzy model and piecewise Lyapunov function. GH2 stability sufficient conditions are derived in terms of linear matrix inequalities (LMIs). The interactions among the fuzzy subsystems are considered. Therefore, the proposed conditions are less conservative than the previous results. Since only a set of LMIs is involved, the controller design is quite simple and numerically tractable. To illustrate the validity of the proposed method, a design example is provided. 展开更多
关键词 generalized H2 (GH2) control fuzzy systems linear matrix inequalities (LMIs) piecewise Lyapunov function switchingfuzzy model.
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Safety Performance Functions for Traffic Signals:Phasing and Geometry
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作者 Shane Turner 《Journal of Civil Engineering and Architecture》 2023年第4期199-213,共15页
A significant proportion of urban crashes,especially serious and fatal crashes,occur at traffic signals.Many of the black-spots in both Australia and New Zealand cities occur at high volume and/or high-speed traffic s... A significant proportion of urban crashes,especially serious and fatal crashes,occur at traffic signals.Many of the black-spots in both Australia and New Zealand cities occur at high volume and/or high-speed traffic signals.Given this,crash reduction studies often focus on the major signalised intersections.However,there is limited information that links the phasing configuration,degree of saturation and overall cycle time to crashes.While a number of analysis tools are available for assessing the efficiency of intersections,there are very few tools that can assist engineers in assessing the safety effects of intersection upgrades and new intersections.Safety performance functions have been developed to help quantify the safety impact of various traffic signal phasing configurations and level of intersection congestion at low and high-speed traffic signals in New Zealand and Australia.Data from 238 signalised intersection sites in Auckland,Wellington,Christchurch,Hamilton,Dunedin and Melbourne was used to develop crash prediction models for key crash-causing movements at traffic signals.Different variables(road features)effect each crash type.The models indicate that the safety of intersections can be improved by longer cycle times and longer lost inter-green times,especially all-red time,using fully protected right turns and by extending the length of right turn bays.The exception is at intersections with lots of pedestrians where shorter cycle times are preferred as pedestrian crashes increase with longer wait times.A number of factors have a negative impact on safety including,free left turns,more approach lanes,intersection arms operating near or over capacity in peak periods and higher speed limits. 展开更多
关键词 Crash/Accident prediction models generalized linear models traffic signal layout and phasing pedestrian safety and safety performance functions
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功能定量磁化率成像与血氧水平依赖成像在任务态功能MRI脑激活分析中的比较
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作者 郭莹 林丽园 +2 位作者 王淑梅 李威 秦文 《国际医学放射学杂志》 2025年第6期682-689,共8页
目的比较功能定量磁化率成像(fQSM)和血氧水平依赖(BOLD)成像在对指任务功能MRI(fMRI)中检测脑激活的能力。方法前瞻性招募24例健康成人志愿者,采用3.0 T MRI设备同步采集对指运动任务的fMRI幅度及相位图。采用一般线性模型(GLM)和独立... 目的比较功能定量磁化率成像(fQSM)和血氧水平依赖(BOLD)成像在对指任务功能MRI(fMRI)中检测脑激活的能力。方法前瞻性招募24例健康成人志愿者,采用3.0 T MRI设备同步采集对指运动任务的fMRI幅度及相位图。采用一般线性模型(GLM)和独立成分分析(ICA)成像提取任务诱发的BOLD以及fQSM脑激活图。采用相关分析探讨BOLD和f QSM脑激活成分时间序列的相似性,采用配对t检验或置换检验比较BOLD和fQSM脑激活成分动态范围和分数低频振幅的差别。结果GLM显示BOLD激活脑区主要位于双侧中央前后回和小脑运动区,而fQSM未检测到激活的脑区(体素水平P<0.001,团块水平FWEc校正P<0.05)。即使降低阈值,fQSM检测到的激活也远少于BOLD,且两者在小脑运动区的时间序列呈显著负相关。头动和空间平滑对BOLD及fQSM激活强度的影响不显著。固定成分数(90)的ICA显示,BOLD能敏感检测到与对指任务时序密切关联的脑激活独立成分,而fQSM未能检测到与任务相关的脑激活,BOLD和fQSM各激活成分时间序列相关性较弱,且BOLD激活成分时间序列的动态范围和分数低频振幅显著高于fQSM(P<0.05,Bonferroni校正)。此外,自动成分数选择的ICA识别到3个与运动显著关联的f QSM脑激活成分,包括感觉运动、内侧前额叶和小脑运动网络,且后者与BOLD感觉运动网络存在显著负相关。结论fQSM技术在手指运动相关脑激活方面的检测能力低于BOLD技术,使用自动成分数选择的ICA有助于提高fQSM脑激活检测能力。 展开更多
关键词 血氧水平依赖 功能定量磁化率成像 功能磁共振成像 一般线性模型 独立成分分析
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