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Projected Changes in Temperature and Precipitation Extremes over China as Measured by 50-yr Return Values and Periods Based on a CMIP5 Ensemble 被引量:15
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作者 Ying XU Xuejie GAO +4 位作者 Filippo GIORGI Botao ZHOU Ying SHI Jie WU Yongxiang ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第4期376-388,共13页
Future changes in the 50-yr return level for temperature and precipitation extremes over China's Mainland are investigated based on a CMIP5 multi-model ensemble for RCP2.6, RCP4.5 and RCP8.5 scenarios. The followi... Future changes in the 50-yr return level for temperature and precipitation extremes over China's Mainland are investigated based on a CMIP5 multi-model ensemble for RCP2.6, RCP4.5 and RCP8.5 scenarios. The following indices are analyzed: TXx and TNn (the annual maximum and minimum of daily annual maximum consecutive 5-day precipitation) and CDD maximum and minimum surface temperature), RX5day (the (maximum annual number of consecutive dry days). After first validating the model performance, future changes in the 50-yr return values and return periods for these indices are investigated along with the inter-model spread. Multi-model median changes show an increase in the 50-yr return values of TXx and a decrease for TNn, more specifically, by the end of the 21st century under RCP8.5, the present day 50-yr return period of warm events is reduced to 1.2 yr, while extreme cold events over the country are projected to essentially disappear. A general increase in RX5day 50-yr return values is found in the future. By the end of the 21st century under RCP8.5, events of the present RX5day 50-yr return period are projected to reduce to 〈 10 yr over most of China. Changes in CDD-50 show a dipole pattern over China, with a decrease in the values and longer return periods in the north, and vice versa in the south. Our study also highlights the need for further improvements in the representation of extreme events in climate models to assess the future risks and engineering design related to large-scale infrastructure in China. 展开更多
关键词 CMIP5 EXTREMES return values and periods China
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SOLUTIONS TO DISCRETE MULTIPARAMETER PERIODIC BOUNDARY VALUE PROBLEMS INVOLVING THE p-LAPLACIAN VIA CRITICAL POINT THEORY 被引量:8
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作者 高承华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1225-1236,共12页
In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value ... In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value problems in [C. Bonanno and P. Candito, Appl. Anal., 88(4) (2009), pp. 605-616], we construct two new strong maximum principles and obtain that the boundary value problem has three positive solutions for λ and μ in some suitable intervals. The approaches we use are the critical point theory. 展开更多
关键词 discrete periodic boundary value problem P-LAPLACIAN MULTIPARAMETER three solutions critical point theory
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Periodic boundary value problem for the first order functional differential equations with impulses 被引量:5
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作者 LIANG Rui-xi SHEN Jian-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第1期27-35,共9页
This paper is concerned with the existence and approximation of solutions for a class of first order impulsive functional differential equations with periodic boundary value conditions. A new comparison result is pres... This paper is concerned with the existence and approximation of solutions for a class of first order impulsive functional differential equations with periodic boundary value conditions. A new comparison result is presented and the previous results are extended. 展开更多
关键词 functional differential equation periodic boundary value problem lower and upper solution monotone iterative method
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Second Order Periodic Boundary Value Problems Involving the Distributional Henstock-Kurzweil Integral 被引量:3
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作者 Xueyuan Zhou Guoju Ye 《Advances in Pure Mathematics》 2012年第5期330-336,共7页
We apply the distributional derivative to study the existence of solutions of the second order periodic boundary value problems involving the distributional Henstock-Kurzweil integral. The distributional Henstock-Kurz... We apply the distributional derivative to study the existence of solutions of the second order periodic boundary value problems involving the distributional Henstock-Kurzweil integral. The distributional Henstock-Kurzweil integral is a general intergral, which contains the Lebesgue and Henstock-Kurzweil integrals. And the distributional derivative includes ordinary derivatives and approximate derivatives. By using the method of upper and lower solutions and a fixed point theorem, we achieve some results which are the generalizations of some previous results in the literatures. 展开更多
关键词 periodic Boundary value Problem Distributional Henstock-Kurzweil INTEGRAL Distributional DERIVATIVE EXISTENCE UPPER and LOWER Solutions Fixed Point
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Periodic Boundary Value Problem for Functional Differential Equations with Impulses
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作者 何智敏 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期347-351,共5页
Aim To investigate the periodic boundary value problem for functional differential equations with impulses. Methods The method of upper and lower solutions and the monotone iterative technique were used to establish... Aim To investigate the periodic boundary value problem for functional differential equations with impulses. Methods The method of upper and lower solutions and the monotone iterative technique were used to establish our results. Results and Conclusion The results of the existence of maximal and minimal solutions of the periodic boundary value problem for functional differential equations with impulses are obtained. 展开更多
关键词 functional differential equation upper and lower solutions monotone iterative technique periodic boundary value problem IMPULSE
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EXISTENCE OF SOLUTIONS FOR PERIODIC BOUNDARY VALUE PROBLEMS FOR SECOND-ORDER INTEGRO-DIFFERENTIAL EQUATIONS 被引量:1
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作者 洪世煌 胡适耕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第3期355-362,共8页
By establishing a comparison result and using monotone iterative methods, the theorem of existence for minimal and maximal solutions of periodic boundary value problems for second-order nonlinear integro-differential ... By establishing a comparison result and using monotone iterative methods, the theorem of existence for minimal and maximal solutions of periodic boundary value problems for second-order nonlinear integro-differential equations in Banach spaces is proved. 展开更多
关键词 ordered Banach spaces periodic boundary value problems maximal and minimal solutions
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PERIODIC BOUNDARY VALUE PROBLEMS FOR NONLINEAR IMPULSIVEINTEGRODIFFERENTIAL EQUATIONS OF MIXED TYPE IN BANACH SPACES 被引量:1
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作者 韦忠礼 《Acta Mathematica Scientia》 SCIE CSCD 1997年第1期35-43,共9页
In this paper, the author obtains an existence theorem of minimal and maximal solutions for the periodic boundary value problems of nonlinear impulsive integrodifferential equations of mixed type in Banach space by me... In this paper, the author obtains an existence theorem of minimal and maximal solutions for the periodic boundary value problems of nonlinear impulsive integrodifferential equations of mixed type in Banach space by means of the monotone iterative technique and cone theory based on a comparison result. 展开更多
关键词 CE PN EPC periodIC BOUNDARY value PROBLEMS FOR NONLINEAR IMPULSIVEINTEGRODIFFERENTIAL EQUATIONS OF MIXED TYPE IN BANACH SPACES EI
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Periodic Boundary Value Problem for Second-order Impulsive Integro-differential Equation
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作者 ZHANG Lin-li LIU An-ping LIU Wei-an 《Chinese Quarterly Journal of Mathematics》 2015年第2期227-235,共9页
In this paper, the properties of solution of periodic boundary value problem for second-order impulsive integro-differential equation are discussed. Using the iterative analysis method, the existence and uniqueness of... In this paper, the properties of solution of periodic boundary value problem for second-order impulsive integro-differential equation are discussed. Using the iterative analysis method, the existence and uniqueness of periodic solution and the sufficient condition for uniform stability of trivial solution are obtained, which extend the previous results on integro-differential equation in periodic boundary value problem. 展开更多
关键词 iterative analysis periodic boundary value problem EXISTENCE STABILITY
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On Monotone Method for Second Order Periodic Boundary Value Problems and Periodic Solutions of Functional Difference Equations
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作者 左文杰 林晓宁 蒋达清 《Northeastern Mathematical Journal》 CSCD 2005年第3期315-322,共8页
In this paper, we show that the method of monotone iterative technique is valid to obtain two monotone sequences that converge uniformly to extremal solutions to second order periodic boundary value problems and perio... In this paper, we show that the method of monotone iterative technique is valid to obtain two monotone sequences that converge uniformly to extremal solutions to second order periodic boundary value problems and periodic solutions of functional difference equations. We obtain some new results under the lower solution α and upper solutionβ with α≤β 展开更多
关键词 periodic boundary value problem periodic solution EXISTENCE upper and lower solution monotone iterative technique
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Periodic Boundary Value Problems for Functional Differential Equations
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作者 QIAi-qin CAO Li 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期244-251,共8页
The periodic boundary value problems for nonlinear functional differential equa- tions was discussed.The existence of maximal and minimal solutions was obtained when the lower and upper solutions satisfied the formal ... The periodic boundary value problems for nonlinear functional differential equa- tions was discussed.The existence of maximal and minimal solutions was obtained when the lower and upper solutions satisfied the formal or reverse order. 展开更多
关键词 periodic boundary value problem monotone iterative technique maximal andminimal solutions
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Chinese Thoughts on domain on the value of standard during the period of social transition
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作者 Ping-JingQiu 《International Journal of Technology Management》 2014年第5期19-21,共3页
values occupy an important position in the lives of the people, almost all the joy, happiness, sadness, unfortunately are related with the values. It pervades all aspects of social life, reflects the contradictions an... values occupy an important position in the lives of the people, almost all the joy, happiness, sadness, unfortunately are related with the values. It pervades all aspects of social life, reflects the contradictions and conflicts of the various aspects. While Chinese society is undergoing a transformation of the special period, Social value orientation of instability makes further thought and exploration,in order to get a judgement conform to social development and human interests of social value standard. 展开更多
关键词 Transition period value DOMAIN
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Integral Operator Solving Process of the Boundary Value Problem of Abstract Kinetic Equation with the First Kind of Critical Parameter and Generalized Periodic Boundary Conditions
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作者 YU De-jian 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期110-117,共8页
In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space whic... In this paper the concepts of the boundary value problem of abstract kinetic equation with the first kind of critical parameter γ 0 and generalized periodic boundary conditions are introduced in a Lebesgue space which consists of functions with vector valued in a general Banach space, and then describe the solution of these abstract boundary value problem by the abstract linear integral operator of Volterra type. We call this process the integral operator solving process. 展开更多
关键词 abstract kinetic equation with the first kind of critical parameter boundary value problem of abstract kinetic equation generalized periodic boundary conditions abstract linear integral operator of Volterra type integral operator solving process
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Explicit One-Step P-Stable Methods for Second Order Periodic Initial Value Problems
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作者 Qinghong Li Yongzhong Song 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第3期237-247,共11页
In this paper, we present an explicit one-step method for solving periodic initial value problems of second order ordinary differential equations. The method is P-stable, and of first algebraic order and high phase-la... In this paper, we present an explicit one-step method for solving periodic initial value problems of second order ordinary differential equations. The method is P-stable, and of first algebraic order and high phase-lag order. To improve the algebraic order, we give a composition second order scheme with the proposed method and its adjoint. We report some numerical results to illustrate the efficiency of our methods. 展开更多
关键词 周期初值问题 周期间隔 P-稳定 相位滞后
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A TWO-STEP EXPLICIT METHOD FOR A CLASS OF LINEAR PERIODIC INITIAL VALUE PROBLEMS
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作者 李庆宏 罗亮生 吴新元 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2003年第1期83-90,共8页
This paper presents a two-step explicit method of order four for solving aclass of linear periodic initial value problems. At each computational step, only tworight function evaluations and one derivative evaluation a... This paper presents a two-step explicit method of order four for solving aclass of linear periodic initial value problems. At each computational step, only tworight function evaluations and one derivative evaluation are employed. Basing on aspecial vector operation, the method can be extended to the vector-applicable in multi-dimensional space. 展开更多
关键词 线性周期初值问题 二步显式方法 特征方程 矢量积
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Determining the time and space domains forestimating b value in seismic zoning
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作者 黄玮琼 李文香 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第5期3-8,共6页
To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M... To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M S8.5 are larger than that delineated in general seismic zone. Two-level statistical units are considered in this paper. The seismic province is the first level unit that is suitable for group of earthquakes including the great shock of M S8.5. A seismic province can be divided into several seismic zones. They can be taken as the second level unit for group of quakes in which the super magnitude of the greatest shock do not exceed 8. Because of the nonstationarity in time of seismic activity, the unbalancedness of data and differential of seismic temporal series feature in different areas need to be considered when we select the time period for estimating b value. According to local conditions, the time period is selected at one′s discretion in order to reflect seismicity level of this statistical unit in future 100 years. 展开更多
关键词 estimating b value statistical unit time period magnitude interval
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Partial or Truncated Sharing Values of Meromorphic Functions with Their Shifts
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作者 lian gui chen jun-fan +1 位作者 cai xiao-hua ji you-qing 《Communications in Mathematical Research》 CSCD 2018年第4期343-350,共8页
We mainly study the periodicity theorems of meromorphic functions having truncated or partial sharing values with their shifts, where meromorphic functions are of hyper order less than 1 and N(r, f) aT(r; f) for s... We mainly study the periodicity theorems of meromorphic functions having truncated or partial sharing values with their shifts, where meromorphic functions are of hyper order less than 1 and N(r, f) aT(r; f) for some positive number a. 展开更多
关键词 meromorphic function periodICITY truncated sharing value partial sharing value
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The Existence and Uniqueness of the Solution for Perio dical Boundary Value Problems of 2k th Order Differential Equations with Resonance
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作者 FENG Yan-qing WANG Zhong-ying 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期203-209,共7页
In this paper, a new set of sufficient conditions related to an initial value problem and global homeomorphism is obtained in discussing the existence and uniqueness of 2π-periodic solution for 2kth order differentia... In this paper, a new set of sufficient conditions related to an initial value problem and global homeomorphism is obtained in discussing the existence and uniqueness of 2π-periodic solution for 2kth order differential equations with resonance. The key role is played by nonnegative auxiliary scalar coercive function. The result of this paper generalizes some existed theorems. 展开更多
关键词 initial value problem global homeomorphism periodic solution nonnegative auxiliary scalar coercive function RESONANCE
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Extreme Values Approach in Food Risk Modeling
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作者 Komla Elom Adedje Diakarya Barro 《Open Journal of Statistics》 2022年第5期691-710,共20页
In this paper we estimate the incubation period of a possible pathology following exposure to dioxins during a poor diet. The tools developed for this purpose include the probabilistic extremal model and the stochasti... In this paper we estimate the incubation period of a possible pathology following exposure to dioxins during a poor diet. The tools developed for this purpose include the probabilistic extremal model and the stochastic behavior of the distribution tails of the contamination. We propose a cumulative distribution function for a random variable that follows both a Gaussian distribution and a GPD. A global optimization method is also explored for the efficient estimation of parameters of GPD. 展开更多
关键词 Extreme values TAIL DIOXIN Dietary Risk Incubation period
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Analysis of Design Rainstorm Hydrograph Based on Asymmetrical Extreme Value Copula
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作者 Zishen CHEN Lingling ZHAO Xing YANG 《Meteorological and Environmental Research》 CAS 2020年第3期38-43,共6页
In this paper,the maximum 1-hour rainfall( rain peak),the maximum 6-hour rainfall and the maximum 24-hour rainfall in the Caojiang River basin from 1967 to 2013 were taken as samples. The typical typhoon rainstorm hyd... In this paper,the maximum 1-hour rainfall( rain peak),the maximum 6-hour rainfall and the maximum 24-hour rainfall in the Caojiang River basin from 1967 to 2013 were taken as samples. The typical typhoon rainstorm hydrograph of joint distribution of rainfall in three periods was constructed based on the asymmetric Archimedean Gumbel-Hougaard extreme value Copula. The main conclusions were as follows:( 1) the design rainstorm value in the Caojiang River basin calculated by using the joint distribution of rainfall in three periods was larger than the design rainstorm value of the joint distribution in two periods and that of a single period. The design rainstorm process hydrograph amplified at the same frequency had the optimal overall effect,which provided a new idea and method for studying the design rainfall patterns.( 2) According to the maximum 24-hour rainfall,the risk rate of the multi-peak rainstorm process that the main peak was in the back was the highest,and the constructed typical design rainstorm process hydrograph was the most representative.( 3) " OR" joint return period of rainfall combination in three periods as the design criteria of a watershed was applicable to responding to the risk of rainfall and flood in this watershed. 展开更多
关键词 Asymmetrical extreme value Copula Design rainstorm hydrograph "OR"return period Rainfall patterns
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基于整数小波变换的Ray-Period压缩算法 被引量:10
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作者 王学伟 孙金凤 王琳 《电网技术》 EI CSCD 北大核心 2008年第7期46-50,共5页
为解决基于传统小波变换的数据压缩方法存在的问题,在深入分析整数提升过程的基础上,提出了一种基于整数小波变换的Ray-Period压缩算法。该算法针对电力数据的特点,根据整数小波变换多分辨率分析的特性,将原始数据变换到小波域,以使变... 为解决基于传统小波变换的数据压缩方法存在的问题,在深入分析整数提升过程的基础上,提出了一种基于整数小波变换的Ray-Period压缩算法。该算法针对电力数据的特点,根据整数小波变换多分辨率分析的特性,将原始数据变换到小波域,以使变换后的信号能量主要集中在低频系数上,而后采用无损的Ray-Period压缩算法处理低频数据,采用改进的阈值压缩算法处理高频系数,并采用新的位图压缩算法处理阈值压缩后元素值超过3.125%时的非零元素。采用实际数据进行压缩,该算法的能量恢复系数优于10?4,压缩比小于6.39%,速度比传统的小波变换压缩算法提高了近1倍。 展开更多
关键词 数据压缩 提升算法 整数小波变换 Ray—period 阈值
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