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ON VALUE DISTRIBUTIONS OF GENERAL DIFFERENTIAL MONOMIALS
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作者 吴天毅 李伟 程英 《Transactions of Tianjin University》 EI CAS 2001年第1期68-70,共3页
Value distributions of the general differential monomials is discussed.The following theorem is obtained:Let f be a transcendental meromorphic function in the plane,F=f n 0 (f (i) ) n i …(f (k) ) ... Value distributions of the general differential monomials is discussed.The following theorem is obtained:Let f be a transcendental meromorphic function in the plane,F=f n 0 (f (i) ) n i …(f (k) ) n k -c,n i≥1,c≠0 be a constant then (n 0-2)T(r,f)≤(r,1F)+S(r,f) when n 0】2;T(r,f)≤7(i+1)i( i) (r,1f)+(r,1F))+S(r,f) when n 0=1;T(r,f)≤7(N(r,1f)+(r,1F))+S(r,f) when n 0=0. 展开更多
关键词 meromorphic function differential monomial differential polynomial value distribution
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Extreme value distribution and reliability of nonlinear stochastic structures 被引量:7
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作者 陈建兵 李杰 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第2期275-286,共12页
A new approach to evaluate the extreme value distribution (EVD) of the response and reliability of general multi-DOF nonlinear stochastic structures is proposed. The approach is based on the recently developed proba... A new approach to evaluate the extreme value distribution (EVD) of the response and reliability of general multi-DOF nonlinear stochastic structures is proposed. The approach is based on the recently developed probability density evolution method, which enables the instantaneous probability density functions of the stochastic responses to be captured. In the proposed method, a virtual stochastic process is first constructed to satisfy the condition that the extreme value of the response equals the value of the constructed process at a certain instant of time. The probability density evolution method is then applied to evaluate the instantaneous probability density function of the response, yielding the EVD. The reliability is therefore available through a simple integration over the safe domain. A numerical algorithm is developed using the Number Theoretical Method to select the discretized representative points. Further, a hyper-ball is imposed to sieve the points from the preceding point set in the hypercube. In the numerical examples, the EVD of random variables is evaluated and compared with the analytical solution. A frame structure is analyzed to capture the EVD of the response and the dynamic reliability. The investigations indicate that the proposed approach provides reasonable accuracy and efficiency. 展开更多
关键词 extreme value distribution RELIABILITY NONLINEAR probability density evolution method number theoreticalmethod
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A New Method for Determining Threshold in Using PGCEVD to Calculate Return Values of Typhoon Wave Height 被引量:4
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作者 罗耀 朱良生 胡金鹏 《China Ocean Engineering》 SCIE EI 2012年第2期251-260,共10页
In using the PGCEVD (Poisson-Gumbel Compound Extreme Value Distribution) model to calculate return values of typhoon wave height, the quantitative selection of the threshold has blocked its application. By analyzing... In using the PGCEVD (Poisson-Gumbel Compound Extreme Value Distribution) model to calculate return values of typhoon wave height, the quantitative selection of the threshold has blocked its application. By analyzing the principle of the threshold selection of PGCEVD model and in combination of the change point statistical methods, this paper proposes a new method for quantitative calculation of the threshold in PGCEVD model. Eleven samples from five engineering points in several coastal waters of Guangdong and Hainan, China, are calculated and analyzed by using PGCEVD model and the traditional Pearson type III distribution (P-III) model, respectively. By comparing the results of the two models, it is shown that the new method of selecting the optimal threshold is feasible. PGCEVD model has more stable results than that of P-III model and can be used for the return wave height in every direction. 展开更多
关键词 POT Compound Extreme value distribution Pearson type II1 mean change point extreme wave height
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Research on the Spatial Distribution of Ecosystem Service Value in Guangxi and Its Ecological Protection Countermeasure
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作者 童新芳 周兴 《Meteorological and Environmental Research》 CAS 2010年第1期75-78,92,共5页
90 counties (cities) in Guangxi Province being taken as the tested region,the ecosystem service value of those counties (cities) was measured with the data of land-using in 2005 by means of the Table of Terrestrial Ec... 90 counties (cities) in Guangxi Province being taken as the tested region,the ecosystem service value of those counties (cities) was measured with the data of land-using in 2005 by means of the Table of Terrestrial Ecosystem Services Value in China.The result indicated that the value of the ecosystem services per unit was divided into 3 categories:the first category with high ecosystem services value,the second category with medium ecosystem services value and the third category with low ecosystem services value.The region of the first category was mainly distributed in the mountain area of northern,northwestern,eastern and northeast part of Guangxi;the second category,in the hilly area of southern part and the mountain area in the southwestern part of Guangxi and the third category,in the basin area of central Guangxi,the karst area of western and northwestern Guangxi Province. 展开更多
关键词 Ecosystem service value Spatial distribution of ecosystem service value Ecological protection China
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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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ON THE SINGULAR DIRECTIONS OF VALUE DISTRIBUTION OF HOLOMORPHIC CURVES IN P^n(C) 被引量:2
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作者 涂振汉 李平丽 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期702-710,共9页
This article proves the existence of singular directions of value distribution theory for some transcendental holomorphic curves in the n-dimensional complex projective space P^n(C).. An example is given to compleme... This article proves the existence of singular directions of value distribution theory for some transcendental holomorphic curves in the n-dimensional complex projective space P^n(C).. An example is given to complement these results. 展开更多
关键词 Complex projective spaces holomorphic mappings normal families singular directions and value distribution theory
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THE VALUE DISTRIBUTION OF RANDOM ANALYTIC DIRICHLET SERIES OF NEUTRAL GROWTH (Ⅱ) 被引量:1
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作者 丁晓庆 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期504-510,共7页
This paper studies the value distribution of random analytic Dirichlet series f(s) = Zn()e-sn, where {Zn} is a sequence of independent random variables, n = 1 with moments zero, such that infE{Zn}/E1/2{Zn2≥ α > ... This paper studies the value distribution of random analytic Dirichlet series f(s) = Zn()e-sn, where {Zn} is a sequence of independent random variables, n = 1 with moments zero, such that infE{Zn}/E1/2{Zn2≥ α > 0. Suppose [h*(σ)]2 = n converges for any α > 0, and diverges for = 0. It is shown that if = ρ E (0, ), then with probability one, where β is a constant depending only upon the constant α. 展开更多
关键词 value distribution exceptional value random Dirichlet series independent random variab
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Estimation of Poisson-Generalized Pareto Compound Extreme Value Distribution by Probability-Weighted Moments and Empirical Analysis 被引量:4
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作者 刘晶 史道济 吴新荣 《Transactions of Tianjin University》 EI CAS 2008年第1期50-54,共5页
This paper puts forward a Poisson-generalized Pareto (Poisson-GP) distribution. This new form of compound extreme value distribution expands the existing application of compound extreme value distribution, and can be ... This paper puts forward a Poisson-generalized Pareto (Poisson-GP) distribution. This new form of compound extreme value distribution expands the existing application of compound extreme value distribution, and can be applied to predicting financial risk, large insurance settlement and high-grade earthquake, etc. Compared with the maximum likelihood estimation (MLE) and compound moment estimation (CME), probability-weighted moment estimation (PWME) is used to estimate the parameters of the distribution function. The specific formulas are presented. Through Monte Carlo simulation with sample sizes 10, 20, 50, 100, 1 000, it is concluded that PWME is an efficient method and it behaves steadily. The mean square errors (MSE) of estimators by PWME are much smaller than those of estimators by CME, and there is no significant difference between PWME and MLE. Finally, an example of foreign exchange rate is given. For Dollar/Pound exchange rates from 1990-01-02 to 2006-12-29, this paper formulates the distribution function of the largest loss among the investment losses exceeding a certain threshold by Poisson-GP compound extreme value distribution, and obtains predictive values at different confidence levels. 展开更多
关键词 Poisson-generalized Pareto compound extreme value distribution probability-weightedmoment estimation maximum likelihood estimation compound moment estimation
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Extreme value distributions of mixing two sequences with different MDA's 被引量:2
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作者 蒋岳祥 《Journal of Zhejiang University Science》 CSCD 2004年第5期509-517,共9页
Suppose {Xi, i≥1} and {Yi, i≥1} are two independent sequences with distribution functions FX(x) and FY(x), respectively. Zi is the combination of Xi and Yi with a probability pn for each i with 1≤i≤n. The extreme ... Suppose {Xi, i≥1} and {Yi, i≥1} are two independent sequences with distribution functions FX(x) and FY(x), respectively. Zi is the combination of Xi and Yi with a probability pn for each i with 1≤i≤n. The extreme value distribution ,n GZ(x) of this particular triangular array of the i.i.d. random variables Z1, , Z2, ,…, Zn n n ,nis discussed. We found a new form of the extreme value distribution ΛA(ρx)Λ(x)(0<ρ <1), which is not max-stable. It occurs if FX(x) and FY(x) belong to the same MDA(Λ). GZ(x) does not exist as mixture forms of the different types of extreme value distributions. 展开更多
关键词 Extreme value distribution Maximum domain of attraction(MDA) Mixed distribution functions
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THE VALUE DISTRIBUTION OF RANDOM ANALYTIC DIRICHLET SERIES OF NEUTRAL GROWTH(I) 被引量:1
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作者 Ding Xiaoqing 《Acta Mathematica Scientia》 SCIE CSCD 1999年第2期234-240,共7页
This paper deals with the value distribution of random Dirichlet series whose coefficients are a martingale difference sequence,and which is of neutral growth.
关键词 value distribution RANDOM DIRICHLET series MARTINGALE DIFFERENCE sequence.
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Importance of Generalized Logistic Distribution in Extreme Value Modeling 被引量:1
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作者 K. Nidhin C. Chandran 《Applied Mathematics》 2013年第3期560-573,共14页
We consider a problem from stock market modeling, precisely, choice of adequate distribution of modeling extremal behavior of stock market data. Generalized extreme value (GEV) distribution and generalized Pareto (GP)... We consider a problem from stock market modeling, precisely, choice of adequate distribution of modeling extremal behavior of stock market data. Generalized extreme value (GEV) distribution and generalized Pareto (GP) distribution are the classical distributions for this problem. However, from 2004, [1] and many other researchers have been empirically showing that generalized logistic (GL) distribution is a better model than GEV and GP distributions in modeling extreme movement of stock market data. In this paper, we show that these results are not accidental. We prove the theoretical importance of GL distribution in extreme value modeling. For proving this, we introduce a general multivariate limit theorem and deduce some important multivariate theorems in probability as special cases. By using the theorem, we derive a limit theorem in extreme value theory, where GL distribution plays central role instead of GEV distribution. The proof of this result is parallel to the proof of classical extremal types theorem, in the sense that, it possess important characteristic in classical extreme value theory, for e.g. distributional property, stability, convergence and multivariate extension etc. 展开更多
关键词 Financial Risk MODELING STOCK Market Analysis GENERALIZED Logistic distribution GENERALIZED Extreme value distribution TAIL EQUIVALENCE Maximum Stability Random Sample size Limit distribution
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THE DISTRIBUTION OF VALUES OF TAYLOR SERIES 被引量:1
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作者 余家荣 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期1719-1726,共8页
Clarify some classical results and their proofs on the distribution of values of simple Taylor series and extend them to multiple Taylor series.
关键词 simple and multiple Taylor series distribution of values
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THE VALUE DISTRIBUTION OF GAUSS MAPS OF IMMERSED HARMONIC SURFACES WITH RAMIFICATION 被引量:1
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作者 Zhixue LIU Yezhou LI Xingdi CHEN 《Acta Mathematica Scientia》 SCIE CSCD 2022年第1期172-186,共15页
Motivated by the result of Chen-Liu-Ru[1],we investigate the value distribution properties for the generalized Gauss maps of weakly complete harmonic surfaces immersed in R^(n) with ramification,which can be seen as a... Motivated by the result of Chen-Liu-Ru[1],we investigate the value distribution properties for the generalized Gauss maps of weakly complete harmonic surfaces immersed in R^(n) with ramification,which can be seen as a generalization of the results in the case of the minimal surfaces.In addition,we give an estimate of the Gauss curvature for the K-quasiconfomal harmonic surfaces whose generalized Gauss map is ramified over a set of hyperplanes. 展开更多
关键词 value distribution harmonic surfaces quasiconformal mappings conformal metric Gauss map
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Diagnostic value of combined detection of myocardial markers, white blood cell count and platelet distribution width in patients with positive myocardial injury markers 被引量:1
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作者 Xiao-Lan Hu Ting-Wang Jiang Ben Yin 《Journal of Hainan Medical University》 2019年第1期18-21,共4页
Objective:To explore the diagnostic value of combined detection of myocardial markers, white blood cell (WBC) counts and platelet distribution width (PDW) in patients with positive myocardial injury markers.Methods: F... Objective:To explore the diagnostic value of combined detection of myocardial markers, white blood cell (WBC) counts and platelet distribution width (PDW) in patients with positive myocardial injury markers.Methods: From January 2017 to January 2018, 100 patients with positive markers of myocardial injury in our hospital were selected as observation group, and 100 healthy people were selected as control group. Serum myocardial markers troponin I (cTnI), creatine kinase isoenzyme (CK-MB), myoglobin (MYO), WBC count, and PDW levels were measured at admission, and analyzed for individual indicators. And individual and combined detections of these indicators in early diagnosis of acute myocardial infarction (AMI) were analysed.Results: Serum cTnI, CK-MB, MYO, WBC count and PDW level were higher in the observation group than those in the control group, and the difference between the groups was statistically significant. Of the 100 patients with positive myocardial injury markers, 48 (48.00%) were diagnosed with AMI by final clinical diagnosis. Compared with the control group, the positive rate of serum index and the combined detection of five indicators in the observation group were significantly increased. The sensitivity and specificity of the five indicators combined detection and diagnosis of AMI were 95.83% and 94.23%, respectively, which were higher than the individual detection of each index, and the difference was statistically significant.Conclusions: The combined detection of serum cTnI, CK-MB, MYO, WBC count and PDW is helpful for early diagnosis of AMI and can improve the sensitivity and specificity of diagnosis. 展开更多
关键词 MYOCARDIAL injury MARKERS LEUKOCYTE COUNT PLATELET distribution WIDTH Diagnostic value
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Extreme value distributions of mixing two sequences with the same MDA
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作者 蒋岳祥 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2004年第3期86-93,共8页
Suppose {Xi, i 1} and {Yi, i 1} are two independent sequences with distribution functions ()XFx and ()YFx, respectively. Zi,n is the combination of Xi and Yi with a probability np for each i with 1 in. The extreme val... Suppose {Xi, i 1} and {Yi, i 1} are two independent sequences with distribution functions ()XFx and ()YFx, respectively. Zi,n is the combination of Xi and Yi with a probability np for each i with 1 in. The extreme value distribution GZ(x) of this particular triangular array of the i.i.d. random variables Z1,n, Z2,n, ,L Zn,n is discussed. We found a new form of the extreme value distributions i) 12()()AxxaaFF and ii) 12()()AxxaaYY (a1<a2), which are not max-stable. It occurs if FX and FY belong to the same MDA(? or MDA(?. 展开更多
关键词 EXTREME value distribution Maximum domain of ATTRACTION (MDA) Mixed distribution functions
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BACKGROUND VALUES AND TREND DISTRIBUTION OF Cu, Zn AND Ni IN SOILS IN CHINA
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作者 王景华 《Chinese Geographical Science》 SCIE CSCD 1992年第4期67-76,共10页
The background values of Cu, Zn and Ni are discussed based on the analytical data of 21 main soil types collected from various regions in China. According to statistics of many samples, the background value of Cu is 2... The background values of Cu, Zn and Ni are discussed based on the analytical data of 21 main soil types collected from various regions in China. According to statistics of many samples, the background value of Cu is 23.4±10.2 mg/ kg (482 samples), Zn 77.9±2.39 mg/ kg (474 samples), Ni 30.0±12.8 mg/kg (482 samples). 展开更多
关键词 Soil Background valueS of CU ZN and NI TREND distribution
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THE VALUE DISTRIBUTION AND UNIQUENESS OF ONE CERTAIN TYPE OF DIFFERENTIAL-DIFFERENCE POLYNOMIALS
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作者 张克玉 仪洪勋 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期719-728,共10页
In this article, we investigate the distribution of the zeros and uniqueness of differential-difference polynomialsG(z)=(f^n(f^m(z)-1)∏j=1^d f(z+cj)^vj)^(k)-α(z),H(z)=(f^n(f(z)-1)^m∏j=1^d f(z... In this article, we investigate the distribution of the zeros and uniqueness of differential-difference polynomialsG(z)=(f^n(f^m(z)-1)∏j=1^d f(z+cj)^vj)^(k)-α(z),H(z)=(f^n(f(z)-1)^m∏j=1^d f(z+cj)^vj)^(k)-α(z),where f is transcendental entire function of finite order, cj(j = 1,2,…,d), n,m,d, and vj(j = 1, 2,… , d) are integers, and obtain some theorems, which extended and improved many previous results. 展开更多
关键词 MEROMORPHIC UNIQUENESS value distribution differential-difference
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Research on the Distributional Features of and Interrelationships Between the Dissolved Oxygen, Salinity, pH Value and Nutrient Salts in the Honghai Bay Waters
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作者 王小平 贾晓平 +5 位作者 林钦 李纯厚 甘居利 蔡文贵 王增焕 吕晓瑜 《Marine Science Bulletin》 CAS 2000年第1期38-44,共3页
In this paper, the environmental factors are surveyed of the mariculture waters of the Honghai Bay from the late spring to the early summer (June) in 1998. The distributional features and variation laws of dissolved o... In this paper, the environmental factors are surveyed of the mariculture waters of the Honghai Bay from the late spring to the early summer (June) in 1998. The distributional features and variation laws of dissolved oxygen, salinity, pH value and nutrient salts in the sea water are expounded. Also discussed are their relationships between each other. The results show that the contents of dissolved oxygen and pH value in the sea water increase with the increasing temperature from north (except for No.15~17 stations) to south (expect for No.6 station). At the same time it is affirmed that photosynthesis is the major cause of the high contents of dissolved oxygen and pH value. And the nutrient salt shows a negative correlation with salinity. The total content of phytoplankton obviously increased with the reduction of nutrient salts from north to south. 展开更多
关键词 Honghai BAY dissolved oxygen SALINITY pH value NUTRIENT salt distributional FEATURES
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GENERALIZED OPERATORS AND OPERATOR-VALUED DISTRIBUTIONS IN QUANTUM FIELD THEORY 被引量:2
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作者 黄志远 王湘君 王才士 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期145-154,共10页
The relation between generalized operators and operator-valued distributions is discussed so that these two viewpoints can be used alternatively to explain quantum fields.
关键词 White noise analysis quantum fields generalized operator operator-valued distribution
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Further Extension of a Theorem of Values Distribution of Meromorphic Function f^((k))f^n
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作者 WANG YOU-MING 《Communications in Mathematical Research》 CSCD 2009年第3期277-281,共5页
In this paper we derive the fundamental inequality of the theorem of meromorphic functions. It extends some results of Yi Hong-xun et al. As one of its application, we then study the value distribution of f^(k)f^n-c... In this paper we derive the fundamental inequality of the theorem of meromorphic functions. It extends some results of Yi Hong-xun et al. As one of its application, we then study the value distribution of f^(k)f^n-c(z). 展开更多
关键词 transcendental meromorphic function small function value distribution
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