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Fully Distributed Learning for Deep Random Vector Functional-Link Networks
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作者 Huada Zhu Wu Ai 《Journal of Applied Mathematics and Physics》 2024年第4期1247-1262,共16页
In the contemporary era, the proliferation of information technology has led to an unprecedented surge in data generation, with this data being dispersed across a multitude of mobile devices. Facing these situations a... In the contemporary era, the proliferation of information technology has led to an unprecedented surge in data generation, with this data being dispersed across a multitude of mobile devices. Facing these situations and the training of deep learning model that needs great computing power support, the distributed algorithm that can carry out multi-party joint modeling has attracted everyone’s attention. The distributed training mode relieves the huge pressure of centralized model on computer computing power and communication. However, most distributed algorithms currently work in a master-slave mode, often including a central server for coordination, which to some extent will cause communication pressure, data leakage, privacy violations and other issues. To solve these problems, a decentralized fully distributed algorithm based on deep random weight neural network is proposed. The algorithm decomposes the original objective function into several sub-problems under consistency constraints, combines the decentralized average consensus (DAC) and alternating direction method of multipliers (ADMM), and achieves the goal of joint modeling and training through local calculation and communication of each node. Finally, we compare the proposed decentralized algorithm with several centralized deep neural networks with random weights, and experimental results demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 Distributed Optimization Deep Neural Network Random Vector functional-Link (RVFL) Network Alternating direction Method of Multipliers (ADMM)
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A proposed directional function and wind-wave directional spectrum 被引量:4
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作者 Wen Shengchang Wu Kejian +1 位作者 Guan Changlong Sun Shicai and Zhang Dacuo (Institute of Physical Oceanography, Ocean University of Oingdao, Oingdao 266003, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1995年第2期155-166,共12页
A directional function for frequencies equal to and larger than the peak frequency of a wind-wave frequency spectrum is constructed by fitting the angular spreading based on the analytically derived directional spectr... A directional function for frequencies equal to and larger than the peak frequency of a wind-wave frequency spectrum is constructed by fitting the angular spreading based on the analytically derived directional spectrum of Wen et al. (1993, Journal of Oceanography, 49(2), 131~147, 149~172). For frequencies smaller than the peak frequency, the directional function is obtained by comparing and analyzing existing formulas. The nondimensional wind-wave frequency spectrum of Wen et al. (1994, Progress in Natural Seience, 4(4). 407~427;4 (5), 586~596) has been used together with the directional function just mentioned to obtain the directional spectrum for easier application. 展开更多
关键词 Wind-wave directional function directional spectrum
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Three-dimensional free vibration analysis of multi-directional functionally graded piezoelectric annular plates on elastic foundations via state space based differential quadrature method 被引量:3
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作者 M.H.YAS N.MOLOUDI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第4期439-464,共26页
The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric (FGP) annular plate resting on two parameter (Pasternak) elastic foundations is investigated under different... The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric (FGP) annular plate resting on two parameter (Pasternak) elastic foundations is investigated under different boundary conditions. The material properties are assumed to vary continuously along the radial and thickness directions and have exponent-law distribution. A semi-analytical approach named the state space based differential quadrature method (SSDQM) is used to provide an analytical solution along the thickness using the state space method (SSM) and an approximate solution along the radial direction using the one-dimensional differential quadrature method (DQM). The influence of the Winkler and shear stiffness of the foundation~ the material property graded variations, and the circumferential wave number on the nomdimensional natural frequency of multi-directional FGP annular plates is studied. 展开更多
关键词 multi-directional functionally graded PIEZOELECTRIC annular plate freevibration
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AXISYMMETRIC BENDING OF TWO-DIRECTIONAL FUNCTIONALLY GRADED CIRCULAR AND ANNULAR PLATES 被引量:6
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作者 Guojun Nie Zheng Zhong 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第4期289-295,共7页
Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using ... Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using the semi-analytical numerical method in this paper. The deflections and stresses of the plates are presented. Numerical results show the well accuracy and convergence of the method. Compared with the finite element method, the semi-analytical nu- merical method is with great advantage in the computational efficiency. Moreover, study on ax- isymmetric bending of two-directional functionally graded annular plate shows that such plates have better performance than those made of isotropic homogeneous materials or one-directional functionally graded materials. Two-directional functionally graded material is a potential alternative to the one-directional functionally graded material. And the integrated design of materials and structures can really be achieved in two-directional functionally graded materials. 展开更多
关键词 two-directional functionally graded materials circular and annular plates axisym-metric bending semi-analytical numerical method integrated design
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THE BOREL DIRECTIONS OF ALGEBROIDAL FUNCTION AND ITS COEFFICIENT FUNCTIONS 被引量:2
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作者 张少华 张晓梅 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期241-251,共11页
In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk ... In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk are proved. By these theorems, some interesting conclusions are obtained. 展开更多
关键词 Algebroidal function coefficient function Borel direction.
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ON NEVANLINNA DIRECTIONS OF ALGEBROID FUNCTIONS 被引量:5
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作者 卢谦 顾永兴 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期367-375,共9页
In this paper, a notation delta(x)(w) is derived from the counting function N-x(r, w) of branch points of algebriod functions. With this notation, the authors give the definition of the Nevanlinna direction for algebr... In this paper, a notation delta(x)(w) is derived from the counting function N-x(r, w) of branch points of algebriod functions. With this notation, the authors give the definition of the Nevanlinna direction for algebriod functions and discuss its existence in certain condition. By this notation the authors also obtain the numbers of exceptional value of the Julia direction and Borel direction of algebriod functions are not more than 2 + [delta(x) (w)] here [x] implies an maximum integer number which does not exceed x. 展开更多
关键词 Algebriod functions deficient relations Nevanlinna directions
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ON THE NEVANLINNA DIRECTION OF ALGEBROID FUNCTIONS
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作者 张洪申 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1441-1448,共8页
In this paper, we prove that for an algebroid function w(z), the singular direction argz = φ0, satisfying that for arbitrary ε(0 〈 ε 〈 2/π) and any given α ∈ C^^,limr→+∞ log τ/n(τ,φ0-ε,φ0+ε,w=a... In this paper, we prove that for an algebroid function w(z), the singular direction argz = φ0, satisfying that for arbitrary ε(0 〈 ε 〈 2/π) and any given α ∈ C^^,limr→+∞ log τ/n(τ,φ0-ε,φ0+ε,w=a)=+∞ holds with at most; 2v possible exceptional values of a, is the Ncvanlinna direction of w(z). 展开更多
关键词 algebroid function Nevanlinna direction algebroid function Nevanlinna direction
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DIRECT AND ADAPTIVE SLICING ON CAD MODEL OF IDEAL FUNCTIONAL MATERIAL COMPONENTS (IFMC) 被引量:3
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作者 XuDaoming JiaZhenyuan GuoDongming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期139-144,共6页
A brand new direct and adaptive slicing approach is proposed, which canapparently improve the part accuracy and reduce the building time. At least two stages are includedin this operation: getting the crossing contour... A brand new direct and adaptive slicing approach is proposed, which canapparently improve the part accuracy and reduce the building time. At least two stages are includedin this operation: getting the crossing contour of the cutting plane with the solid part anddetermining the layer thickness. Apart from usual SPI algorithm, slicing of the solid model has itsspecial requirements. Enabling the contour line segments of the cross-section as long as possible isone of them, which is for improving manufacturing efficiency and is reached by adaptively adjustingthe step direction and the step size at every crossing point to obtain optimized secant height. Thelayer thickness determination can be divided into two phases: the geometry-based thicknessestimation and the material-based thickness verifying. During the former phase, the geometrytolerance is divided into two parts: a variety of curves are approximated by a circular arc, whichintroduces the first part, and the deviation error between the contour line in LM process and thecircular arc generates the second part. The latter phase is mainly verifying the layer thicknessestimated in the former stage and determining a new one if necessary. In addition, an example usingthis slicing algorithm is also illustrated. 展开更多
关键词 Rapid prototyping Ideal functional material components direct and adaptiveslicing Surface/plane intersection MARCHING
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Direction-dependent functions of physical properties for crystals and polycrystals
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作者 Mojia Huang Mengcheng Chen Tenglong Zheng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期639-649,共11页
Some physical properties of crystals differ in direction n because crystal lattices are often anisotropic. A polycrystal is an aggregate of numerous tiny crystallites. Unless the polycrystal is an isotropic aggregate ... Some physical properties of crystals differ in direction n because crystal lattices are often anisotropic. A polycrystal is an aggregate of numerous tiny crystallites. Unless the polycrystal is an isotropic aggregate of crystallites, the physical properties of the polycrystal vary with n. The direction-dependent functions (DDF) for crystals and polycrystals are introduced to describe the variations of the physical properties in direction n. Until now there are few papers dealing systematically with relations between the DDF and the crystalline orientation distribution. Herein we give general expressions of the DDF for crystals and polycrystals. We discuss the applications of the DDF in describing the physical properties of crystals and polycrystals. 展开更多
关键词 direction-dependent function Orientation distribution function Physical properties of crystals and polycrystals
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Graph-Directed Coalescence Hidden Variable Fractal Interpolation Functions
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作者 Md. Nasim Akhtar M. Guru Prem Prasad 《Applied Mathematics》 2016年第4期335-345,共11页
Fractal interpolation function (FIF) is a special type of continuous function which interpolates certain data set and the attractor of the Iterated Function System (IFS) corresponding to a data set is the graph of the... Fractal interpolation function (FIF) is a special type of continuous function which interpolates certain data set and the attractor of the Iterated Function System (IFS) corresponding to a data set is the graph of the FIF. Coalescence Hidden-variable Fractal Interpolation Function (CHFIF) is both self-affine and non self-affine in nature depending on the free variables and constrained free variables for a generalized IFS. In this article, graph directed iterated function system for a finite number of generalized data sets is considered and it is shown that the projection of the attractors on is the graph of the CHFIFs interpolating the corresponding data sets. 展开更多
关键词 Iterated function System Graph-directed Iterated function System Fractal Interpolation functions Coalescence Hidden Variable FIFs
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Wideband direction-of-arrival estimation based on cubic spline function
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作者 Hongqi Yu David Day-Uei Li +2 位作者 Kun Zhang Jietao Diao Haijun Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第4期688-693,共6页
A new direction-of-arrival (DOA) estimation algorithm for wideband sources is introduced, The new method obtains the output of the virtual arrays in the signal bandwidth using cubic spline function interpolation tec... A new direction-of-arrival (DOA) estimation algorithm for wideband sources is introduced, The new method obtains the output of the virtual arrays in the signal bandwidth using cubic spline function interpolation techniques. The narrowband high- resolution algorithm is then used to get the DOA estimation. This technique does not require any preliminary knowledge of DOA angles. Simulation results demonstrate the effectiveness of the method. 展开更多
关键词 array signal processing wideband sources cubicspline function direction-of-arrival (DOA) estimation.
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On Singular Directions of Entire and Meromorphic Functions
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作者 常建明 宋国栋 任福尧 《Northeastern Mathematical Journal》 CSCD 2000年第4期379-382,共4页
关键词 entire and meromorphic function Martys direction GROWTH
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新时代职业教育服务国家重大战略的价值向度 被引量:2
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作者 赵庆松 苏敏 《高教学刊》 2024年第4期97-100,共4页
新时代背景下,职业教育的战略功能就是其服务国家战略的能力,不同层次的职业教育在服务国家重大战略上各自具有独特的价值意义。服务国家战略是新时代职业教育发展的内在要求,服务国家现代化发展、实现职业教育内涵式发展、深化职业教... 新时代背景下,职业教育的战略功能就是其服务国家战略的能力,不同层次的职业教育在服务国家重大战略上各自具有独特的价值意义。服务国家战略是新时代职业教育发展的内在要求,服务国家现代化发展、实现职业教育内涵式发展、深化职业教育实践性发展是职业教育服务国家重大战略的三个基本价值向度。要着重把握新时代职业教育服务国家战略的功能表现形态,并在技术技能人才培养、产业对接与技术创新、职教文化传承等关键领域主动融入国家战略并准确把握自身定位,有效提升服务国家重大战略的能力和质量。 展开更多
关键词 职业教育 国家重大战略 价值向度 战略功能 发展方向
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引入相量算子和流向算子的天鹰优化算法 被引量:1
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作者 周玉 裴泽宣 +1 位作者 王培崇 陈博 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第2期304-316,共13页
针对天鹰优化算法搜索效率不足,容易陷入局部最优的缺点,提出多策略改进天鹰优化算法(MIAO).引入广义正态分布优化算法(GNDO),将该算法得出的结果与天鹰优化算法第1阶段得出的结果进行比较,筛选出这2种优化算法下的最优值.该操作扩大了... 针对天鹰优化算法搜索效率不足,容易陷入局部最优的缺点,提出多策略改进天鹰优化算法(MIAO).引入广义正态分布优化算法(GNDO),将该算法得出的结果与天鹰优化算法第1阶段得出的结果进行比较,筛选出这2种优化算法下的最优值.该操作扩大了搜索空间,提高了解的质量.引入相量算子,将第2阶段变为自适应的非参数优化,提高算法的高维优化能力.针对天鹰优化算法在迭代后期存在种群多样性降低、局部开发能力不足的问题,在天鹰算法的第3阶段引入流向算子,使信息可以在每个个体间相互传递,提高种群信息的利用率,增强天鹰优化算法的开发性能.通过对16个测试函数寻优对比分析以及Wilcoxon秩和检验可知,MIAO的寻优能力和收敛速度都有较大的提升.为了验证MIAO算法的实用性和可行性,采用所提算法求解减速器设计问题,通过实际工程优化问题的实验对比分析可知,MIAO算法在处理现实优化问题上具有一定的优越性. 展开更多
关键词 天鹰优化算法 广义正态分布优化算法 相量算子 流向算子 测试函数 Wilcoxon秩和检验
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压强变化对氢气激光检测吸收谱线影响分析
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作者 吕妍 龙倩倩 +2 位作者 王迪 李玉爽 濮御 《光电子技术》 CAS 2024年第1期65-71,共7页
为解决涉氢装备泄漏氢气激光检测光谱信号分析中线型选择的问题,建立了氢气激光吸收光谱直接吸收浓度反演过程仿真模型,结合Hitran数据库开展了对三种不同线型函数谱线的重构精度研究,研究了压强变化对三种线型函数下氢气吸收谱线吸收... 为解决涉氢装备泄漏氢气激光检测光谱信号分析中线型选择的问题,建立了氢气激光吸收光谱直接吸收浓度反演过程仿真模型,结合Hitran数据库开展了对三种不同线型函数谱线的重构精度研究,研究了压强变化对三种线型函数下氢气吸收谱线吸收系数的影响。结果表明:Gauss线型函数的氢气吸收谱线重构精度在三种线型函数中最高,其重构误差≤0.02%,Voigt线型函数和Lorentz线型函数的最大重构误差分别为0.37%和2.58%,验证了该仿真算法的精确性和可靠性;三种线型仿真得到峰值吸收系数均随压强增加而增大,在1.01325×10^(4)~5.06625×10^(5)Pa范围内,Lorentz线型的峰值吸收系数最大,该线型下仿真得到的吸收系数峰值最小为Gauss线型的1.38倍、最大为Gauss线型的17.77倍;其值最小为Voigt线型的2.07倍,最大为Voigt线型的18.41倍。本研究为后续深入研究氢气激光吸收光谱检测提供了科学依据,为实际应用提供理论指导和一定参考。 展开更多
关键词 直接吸收 线型函数 重构精度 吸收系数
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考虑时间变化的洪涝灾害损失评估 被引量:2
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作者 王浩 赵铜铁钢 +3 位作者 田雨 陈泽聪 郑炎辉 陈晓宏 《水利学报》 EI CSCD 北大核心 2024年第2期127-136,共10页
洪涝灾害是对我国影响最大的自然灾害之一。聚焦灾害损失评估问题,本文构建了考虑时间变化的洪涝灾害损失函数。一方面,表征灾害损失随着致灾因子强度先递增、而后增幅趋缓的静态S型曲线关系;另一方面,通过量级、形状和位置三个参数综... 洪涝灾害是对我国影响最大的自然灾害之一。聚焦灾害损失评估问题,本文构建了考虑时间变化的洪涝灾害损失函数。一方面,表征灾害损失随着致灾因子强度先递增、而后增幅趋缓的静态S型曲线关系;另一方面,通过量级、形状和位置三个参数综合考虑灾害损失随时间的动态变化情况。基于《中国水旱灾害防御公报》提供的受灾人口、直接经济损失数据,对于各省级行政区2006—2021年洪涝灾害损失进行评估分析。结果表明:通过拟合洪涝灾害损失函数,洪涝灾害损失关于致灾因子强度和时间的三维空间散点图可有效地拓展成为连续的三维空间曲面及二维空间热力图。各省级行政区受灾人口整体上呈现出逐年下降的特征,但随致灾因子强度的增加而趋于增加。各省级行政区直接经济损失则表现出明显的差异,随时间呈现出大幅下降、缓慢下降和略有增加等不同特征。考虑时间变化的洪涝灾害损失函数是变化环境下灾害评估的有效工具,可为区域洪涝灾情评估提供借鉴和参考。 展开更多
关键词 洪涝灾害 致灾因子 损失函数 受灾人口 直接经济损失 非一致性
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基于小震经验格林函数研究中等地震破裂方向性:以2008年攀枝花M_(S)6.1地震为例
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作者 罗艳 赵里 朱音杰 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第1期144-155,共12页
中小地震破裂方向性研究在确定实际发震面以及地震灾害评估中具有非常重要的意义.本文以2008年8月30日攀枝花M_(S)6.1地震为研究实例,以较小余震作为经验格林函数地震,利用表观震源时间函数随台站方位角变化特性,确定了主震的破裂方向... 中小地震破裂方向性研究在确定实际发震面以及地震灾害评估中具有非常重要的意义.本文以2008年8月30日攀枝花M_(S)6.1地震为研究实例,以较小余震作为经验格林函数地震,利用表观震源时间函数随台站方位角变化特性,确定了主震的破裂方向、破裂尺度以及破裂速度,验证了该方法的适用性和可行性.研究结果表明,主震的破裂方向为几乎正南的184°,破裂长度8.05 km,破裂速度3.35 km·s^(-1),进一步确认了主震震源机制解其中沿南北向的节面是地震实际发震面,主震在水平方向沿着南北向元谋断裂从北往南破裂.攀枝花地震震源破裂速度接近地壳剪切波速度,这可能是造成此次地震虽然震级不大但破坏性严重的重要原因.本文综合分析主震的矩心深度、震源机制解、破裂方向性以及构造应力背景等信息,探讨了地震发生的破裂过程以及灾害严重的原因. 展开更多
关键词 中等地震 破裂方向性 经验格林函数 2008年攀枝花地震
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数字化转型与流通产业绿色发展
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作者 丁宁 曾子静 《山东工商学院学报》 2024年第5期80-92,共13页
基于2003—2017年我国省际面板数据,使用NDDF函数测算流通绿色发展水平,实证检验了数字化转型对流通产业绿色发展的影响及其作用机制。研究显示,流通数字化能够显著促进流通产业绿色发展,提高流通产业绿色发展效率。异质性研究显示,行... 基于2003—2017年我国省际面板数据,使用NDDF函数测算流通绿色发展水平,实证检验了数字化转型对流通产业绿色发展的影响及其作用机制。研究显示,流通数字化能够显著促进流通产业绿色发展,提高流通产业绿色发展效率。异质性研究显示,行业不同、环境规制水平不同、流通渠道畅通水平不同,数字化转型对流通产业绿色发展水平的影响有所差异。机制检验表明,流通数字化可以提高流通效率、降低产业能耗,优化产业能源结构从而促进流通业绿色发展。 展开更多
关键词 流通数字化 流通业绿色发展 NDDF
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The Effect of Non-Invasive Goal Directed Fluid Administration on Graft Function in Deceased Donor Renal Transplantation: A Pilot Study
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作者 Joseph R. Whiteley Jason M. Taylor +5 位作者 John J. Freely Jr. Thomas I. Epperson Laura Bell John L. Murray IV Charles F. Bratton William R. Hand 《Open Journal of Organ Transplant Surgery》 2016年第3期13-21,共9页
Background: Non-invasive goal directed fluid therapy during deceased donor renal transplant (CRT) may reduce the incidence of delayed graft function. Plethysmograph Variability Index (PVI) has been shown to predict fl... Background: Non-invasive goal directed fluid therapy during deceased donor renal transplant (CRT) may reduce the incidence of delayed graft function. Plethysmograph Variability Index (PVI) has been shown to predict fluid responsiveness during surgery. This pilot study evaluated the feasibility of goal directed fluid administration protocol based upon PVI studying the incidence of delayed graft function (DGF) in renal transplant recipients. Methods: Twenty patients underwent primary CRT. The Control group received intravenous fluid (IVF) at a calculated constant rate. The Treatment group received a baseline IVF infusion throughout the surgery. PVI values greater than 13% were treated with 250 ml boluses of IVF. Primary end point was DGF;total IVF administration and urinary biomarker NGAL levels were secondary endpoints. Results: Treatment group at every time point received significantly less IVF. There was no significant difference in incidence of DGF between the groups. 2 patients in the Control group and 6 in the Treatment group developed DGF. NGAL was not associated with the group assignment or total IVF given (p < 0.2). Conclusions: The effectiveness of goal directed fluid therapy with non-invasive dynamic parameters has not been validated in renal transplant surgery and larger prospective studies are needed to determine its utility in renal transplantation. 展开更多
关键词 Deceased Donor Renal Transplant Non-Invasive Goal directed Fluid Therapy Delayed Graft function Plethysmograph Variability Index
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中央财政资金直达机制:财政职能优化与治理效能提升
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作者 刘凤 梁双陆 《学术探索》 CSSCI 2024年第8期127-135,共9页
2020年,财政部创新性地建立了中央财政资金直达机制,将部分转移支付资金直达基层财政,此后,直达机制常态化实施并不断扩容。这是建立现代财税制度的重大改革,更是落实党的二十大“应完善转移支付体系,落实好积极的财政政策更加积极有为... 2020年,财政部创新性地建立了中央财政资金直达机制,将部分转移支付资金直达基层财政,此后,直达机制常态化实施并不断扩容。这是建立现代财税制度的重大改革,更是落实党的二十大“应完善转移支付体系,落实好积极的财政政策更加积极有为”的具体体现。本文研究认为,中央财政资金直达机制适配于中国式现代化建设要求,破解了传统转移支付制度中多层委托代理模式存在的弊端,优化了财政的配置职能、分配职能和稳定职能,在不改变政府管理层级体系的前提下,保证了中央财政资金下达时滞最短,支出效率最高,全过程得到监管,使财政政策正效应最大化,体现了稳中求进工作总基调,将有利于促进省以下财政体制改革。 展开更多
关键词 转移支付制度 资金直达 财政职能 财政治理效能
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