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partial EIV模型的非负最小二乘方差分量估计

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测绘学报 2017年第7期46卷 857-865页

作者：王乐洋温贵森东华理工大学测绘工程学院江西南昌330013 流域生态与地理环境监测国家测绘地理信息局重点实验室江西南昌330013 江西省数字国土重点实验室江西南昌330013

partial Errors-in-Variables(partial EIV)模型是EIV模型的扩展形式,权阵构造简单,当系数矩阵中存在非随机元素和随机元素时,partial EIV模型的适用性更强。针对partial EIV模型中随机模型不准确的情况,将系数矩阵和观测向量分别作为... 详细信息

partial Errors-in-Variables(partial EIV)模型是EIV模型的扩展形式,权阵构造简单,当系数矩阵中存在非随机元素和随机元素时,partial EIV模型的适用性更强。针对partial EIV模型中随机模型不准确的情况,将系数矩阵和观测向量分别作为一类数据,本文在该模型的基础上,使用最小二乘方差分量估计方法,推导相关计算公式及迭代算法,分别估计出相应的方差分量估值。并对出现的负方差使用非负最小二乘理论,增加约束条件,对随机模型进行修正,得到更加合理的参数估值。试实验结果表明,本文的方法与其他方差分量估计方法等价。

关键词： partial EIV模型 EIV模型最小二乘方差分量估计非负最小二乘

partial stability analysis of nonlinear time-varying impulsive systems

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International Journal of Biomathematics 2019年第6期12卷 73-98页

作者： Boulbaba Ghanmi Faculty of Sciences of Gafsa University of GafsaSidi Ahmed Zarroug 2112GafsaTunisia

This paper investigates the stability analysis with respect to part of the variables of nonlinear time-varying systems with impulse effect.The approach presented is based on the specially introduced piecewise continuous Lyapunov functions.The Lyapunov stability theorems with respect to part of the variables are generalized in the sense that the time derivatives of the Lyapunov functions are allowed to be indefinite.With the help of the notion of stable functions,asymptotic partial stability,exponential partial stability,input-to-state partial stability(ISPS)and integral input-to-state partial stability(iISPS)are considered.Three numerical examples are provided to illustrate the effectiveness of the proposed theoretical results.

关键词： Nonlinear impulsive systems partial stability piecewise continuous scalar functions indefinite Lyapunov function input-to-state partial stability(ISPS) integral input-to-state partial stability(iISPS).

The Multi-scale Method for Solving Nonlinear Time Space Fractional partial Differential Equations

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 299-306页

作者： Hossein Aminikhah Mahdieh Tahmasebi Mahmoud Mohammadi Roozbahani the Department of Applied Mathematics University of Guilan the Department of Applied Mathematics Faculty of Mathematical SciencesTarbiat Modares University

In this paper, we present a new algorithm to solve a kind of nonlinear time space-fractional partial differential equations on a finite domain. The method is based on B-spline wavelets approximations, some of these functions are reshaped to satisfy on boundary conditions exactly. The Adams fractional method is used to reduce the problem to a system of equations. By multiscale method this system is divided into some smaller systems which have less computations. We get an approximated solution which is more accurate on some subdomains by combining the solutions of these systems. Illustrative examples are included to demonstrate the validity and applicability of our proposed technique, also the stability of the method is discussed.

关键词： Adams fractional method B-spline wavelets multi-scale method nonlinear fractional partial differential equations

Sublethal effects of subzero temperatures on the light brown apple moth, Epiphyas postvittana: fitness costs in response to partial freezing

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Insect Science 2019年第2期26卷 311-321页

作者： Amy C. Morey Robert C. Venette William D. Hutchison Department of Entomology University of Minnesota St. Paul Minnesota USA USDA. Forest Service Northern Research Station St. Paul Minnesota USA

Population responses to envir on mental extremes often dictate the bounds to species' distributions. However, population dynamics at, or near, those range limits may also be affected by sublethal effects. We exposed late instars and pupae of an invasive leafroller, Epiphyaspostvittana (Walker)(Lepidoptera: Tortricidae), to cold temperatures and measured the effects of exposure on subsequent survivorship, development, and reproduction. Cold temperature was applied as acute exposure to -10 °C (a low, but not immediately lethal temperature for this species) or the onset of freezing (the peak of the supercooling point exotherm). Survival was defined as the ability to successfully eclose as an adult. We measured immature development times, pupal mass, and adult longevity as proxies of fitness in survivors. Additionally, surviving insects were mated with individuals that had not been exposed to cold to measure fertility. There was no difference between the proportion of larvae or pupae that survived acute exposure to -10 °C and those exposed to the control temperature. Approximately 17% of larvae and 8% of pupae survived brief periods with internal ice formation and continued development to become reproductively viable adults. Importantly, surviving the onset of freezing came with significant fitness costs but not to exposure to -10 °C;most insects that survived partial freezing had lower fertility and shorter adult lifespans than either the -10 °C or control group. These results are discussed within the context of forecasting invasive in sect distributions.

关键词： fertility invasive species partial freeze tolerance supercooling point

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传感器并联型局部放电监测与定位方法

电工技术学报 2014年第2期29卷 226-230页

作者：高鹏路胡岳刘斌曹灵钰江秀臣盛戈皞电力传输与功率变换控制教育部重点实验室(上海交通大学) 上海200240 山东电力集团公司威海供电公司威海264200

局部放电监测作为绝缘诊断的重要手段,因其能在早期及时有效地发现电气设备的绝缘缺陷,正为电力部门所推广。然而目前变电站局部放电在线监测都是针对单个设备进行的,要对变电站多设备实施监测,需要安装多个监测装置,存在成本高、系统... 详细信息

局部放电监测作为绝缘诊断的重要手段,因其能在早期及时有效地发现电气设备的绝缘缺陷,正为电力部门所推广。然而目前变电站局部放电在线监测都是针对单个设备进行的,要对变电站多设备实施监测,需要安装多个监测装置,存在成本高、系统维护工作量大等问题。本文提出了一种基于传感器并联结构的低成本变电站多设备局部放电监测与初定位方法。该方法通过在一环状信号总线上并联多个安装在不同设备的局部放电传感器,达到仅用一套采集系统监控多个设备的目的,同时利用各个传感器所检测的局部放电脉冲信号到达信号总线两端的时差固定且各自不同,实现局部放电源的初定位。在阐述该新型局部放电监测与初定位原理基础上,本文还对实现该原理的监测系统结构、定位算法进行了初步研究,并进行了实验验证。

关键词：局部放电传感器并联检波信号到达时间差定位 partial discharge (PD) time difference of arrival(TDOA)

partial Iterative Decode of Turbo Codes for On-Board Processing Satellite Platform

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China Communications 2015年第11期12卷 104-111页

作者： LI Hang GAO Zhen ZHAO Ming WANG Jing Department of Electronic Engineering Tsinghua University School of Electronic Information Engineering Tianjin University

There is a contradiction between high processing complexity and limited processing resources when turbo codes are used on the on-board processing(OBP)satellite platform.To solve this problem,this paper proposes a partial iterative decode method for on-board application,in which satellite only carries out limited number of iteration according to the on-board processing resource limitation and the throughput capacity requirements.In this method,the soft information of parity bits,which is not obtained individually in conventional turbo decoder,is encoded and forwarded along with those of information bits.To save downlink transmit power,the soft information is limited and normalized before forwarding.The iteration number and limiter parameters are optimized with the help of EXIT chart and numerical analysis,respectively.Simulation results show that the proposed method can effectively decrease the complexity of onboard processing while achieve most of the decoding gain..

关键词： satellite communication on-board processing partial iterative decoding

Differential evolution based computation intelligence solver for elliptic partial differential equations

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Frontiers of Information Technology & Electronic Engineering 2019年第10期20卷 1445-1456页

作者： Muhammad Faisal FATEH Aneela ZAMEER Sikander MMIRZA Nasir MMIRZA Muhammad Saeed ASLAM Muhammad Asif Zahoor RAJA Department of Electrical Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)Islamabad 45650Pakistan Department of Computer and Information Sciences Pakistan Institute of Engineering and Applied Sciences(PIEAS)Islamabad 45650Pakistan Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences(PIEAS)Islamabad 45650Pakistan School of Electrical and Electronic Engineering University of AdelaideAdelaide 5005Australia Department of Electrical and Computer Engineering COMSATS University IslamabadAttock CampusAttock 43600Pakistan

A differential evolution based methodology is introduced for the solution of elliptic partial differential equations (PDEs) with Dirichlet and/or Neumann boundary conditions. The solutions evolve over bounded domains throughout the interior nodes by minimization of nodal deviations among the population. The elliptic PDEs are replaced by the corresponding system of finite difference approximation, yielding an expression for nodal residues. The global residue is declared as the root-mean-square value of the nodal residues and taken as the cost function. The standard differential evolution is then used for the solution of elliptic PDEs by conversion to a minimization problem of the global residue. A set of benchmark problems consisting of both linear and nonlinear elliptic PDEs has been considered for validation, proving the effectiveness of the proposed algorithm. To demonstrate its robustness, sensitivity analysis has been carried out for various differential evolution operators and parameters. Comparison of the differential evolution based computed nodal values with the corresponding data obtained using the exact analytical expressions shows the accuracy and convergence of the proposed methodology.

关键词： Differential evolution Boundary value problems partial differential equation Finite difference scheme Numerical computing

SUT法偏差改正的partial EIV模型方差分量估计及其精度评定

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大地测量与地球动力学 2019年第7期39卷 711-716,770页

作者：王乐洋丁锐吴璐璐东华理工大学测绘工程学院 330013 国家自然资源部流域生态与地理环境监测重点实验室 330013 江西省数字国土重点实验室 330013 江西水利职业学院建筑工程系 330013

由于部分变量误差(partial errors-in-variables,partial EIV)模型方差分量估计精度评定理论不完善,将SUT采样法应用于partial EIV模型的最小范数二次无偏估计(the minimum norm quadratic unbiased estimator,MINQUE),利用方差分量估计修正随机模型并以此作为先验信息对观测向量进行SUT法采样得到参数的加权均值和二阶精度信息。考虑到非线性模型的偏差,进行偏差改正,再通过SUT法对改正后的参数采样计算二阶精度信息。通过算例实验验证,结合SUT法和方差分量估计求解partial EIV模型,能够有效地避免复杂的求导运算,并获得更为精确的参数估值和合理的二阶精度信息,表明偏差改正的必要性。

关键词： partial EIV模型方差分量估计参数估计偏差改正精度评定

partial Differential Equations and Continuum Mechanics:a Collection of Papers Dedicated to Professor Philippe G. Ciarlet on the Occasion of His 80th Birthday

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Acta Mathematicae Applicatae Sinica 2019年第1期35卷 1-2页

作者： Cristinel MARDARE Tong YANG 不详

Preface This Special Issue in'Acta Mathematicae Applicatae Sinica(English Series)'gathers peer reviewed papers dedicated to Professor Philippe G.Ciarlet on the occasion of his eightieth birthday.Written by friends and colleagues from France and Hong Kong/China,they stand as a testimony of their admiration for an exceptional human being and mathematician.

关键词： partial Differential Equations Continuum Mechanics