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Urban land expansion and arable land loss of the major cities in China in the 1990s 被引量:32
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作者 TAN Minghong LI Xiubin LU Changhe 《Science China Earth Sciences》 SCIE EI CAS 2005年第9期1492-1500,共9页
Based on the land-use data in 1990 and 2000, determined by interpreting Landsat Thematic Mapper (TM) imagery, this paper defines the extent of urban construction land, and extracts patches of urban construction land o... Based on the land-use data in 1990 and 2000, determined by interpreting Landsat Thematic Mapper (TM) imagery, this paper defines the extent of urban construction land, and extracts patches of urban construction land of 145 cities with the largest areas in 1990 and arable land patches around these cities. With these data, this paper analyzes the characteristics of ur- ban construction land expansion and the consequent arable land loss in East, Middle and West China, and further identifies the social, economic and spatial factors of the urban land use changes, using GIS (Geographical Information System) and multivariate regression approaches. The results show that total urban land of the 145 cities expanded by 39.8%, with about 70% of the new urban land converted from arable land in the 1990s. The urban land expansion varied among the three regions, with a value of 43.0% in the East, 33.1% in the West (33.1%) and 17.8% in the Middle. Moreover, mean urban construction land per capita increased by10.7% in the East, but it decreased by 7.7% in the Middle, 1.4% in the West. Statistical analysis indicated that total wages of staff and workers could best explain the differences of urban land expansion. 展开更多
关键词 China urban construction LAND expansion ARABLE LAND loss regional difference neighboring index [i(i)].
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对凝视红外热成像冷反射现象的研究 被引量:19
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作者 杨正 屈恩世 +3 位作者 曹剑中 周泗忠 闫阿奇 刘宇波 《激光与红外》 CAS CSCD 北大核心 2008年第1期35-38,共4页
冷反射现象是在红外热成像系统中制冷的探测器通过前面的光学表面反射而探测到自身的像形成的。控制冷反射是设计红外扫描系统的一个重要指标。在一些光线追迹软件中有对红外扫描系统冷反射的分析工具,却没有优化、分析凝视阵列冷反射... 冷反射现象是在红外热成像系统中制冷的探测器通过前面的光学表面反射而探测到自身的像形成的。控制冷反射是设计红外扫描系统的一个重要指标。在一些光线追迹软件中有对红外扫描系统冷反射的分析工具,却没有优化、分析凝视阵列冷反射的工具。为了控制凝视红外系统的冷反射,一般通过非均匀校正来补偿,但这只对应某一特定的状态校正。当相对于已校正状态的一些条件变化时,冷反射又会重现。通过类比于红外扫描系统,分析了凝视系统的冷反射,并用code v给出了实例。 展开更多
关键词 冷反射 红外凝视阵列 YNi i/i BAR
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Precise Rates in the Law of Iterated Logarithm for the Moment of I.I.D. Random Variables 被引量:11
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作者 Ye JIANG Li Xin ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第3期781-792,共12页
Let{X,Xn;n≥1} be a sequence of i,i.d, random variables, E X = 0, E X^2 = σ^2 〈 ∞.Set Sn=X1+X2+…+Xn,Mn=max k≤n│Sk│,n≥1.Let an=O(1/loglogn).In this paper,we prove that,for b〉-1,lim ε→0 →^2(b+1)∑n=1... Let{X,Xn;n≥1} be a sequence of i,i.d, random variables, E X = 0, E X^2 = σ^2 〈 ∞.Set Sn=X1+X2+…+Xn,Mn=max k≤n│Sk│,n≥1.Let an=O(1/loglogn).In this paper,we prove that,for b〉-1,lim ε→0 →^2(b+1)∑n=1^∞ (loglogn)^b/nlogn n^1/2 E{Mn-σ(ε+an)√2nloglogn}+σ2^-b/(b+1)(2b+3)E│N│^2b+3∑k=0^∞ (-1)k/(2k+1)^2b+3 holds if and only if EX=0 and EX^2=σ^2〈∞. 展开更多
关键词 the law of iterated logarithm strong approximation truncation method i.i.d random variables
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次线性期望下独立同分布随机变量序列的完全收敛
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作者 刘宁华 《长春工业大学学报》 CAS 2024年第1期39-43,共5页
概率空间下,随机变量和的期望等于随机变量期望的和,而在次线性期望空间,随机变量和的期望不再等于随机变量期望的和,经典概率空间中的结果无法直接运用于次线性期望空间。通过研究次线性期望空间下独立同分布(i.i.d.)的随机变量{X,X_(n... 概率空间下,随机变量和的期望等于随机变量期望的和,而在次线性期望空间,随机变量和的期望不再等于随机变量期望的和,经典概率空间中的结果无法直接运用于次线性期望空间。通过研究次线性期望空间下独立同分布(i.i.d.)的随机变量{X,X_(n),n≥1},在满足0<a_(n)/n↑以及0<a_(n)/n↑∞条件下随机变量序列的完全收敛关系,其中{a_(n),n≥1}是一个正的单调递增序列,文中将概率空间下的结果推广到次线性期望空间。 展开更多
关键词 完全收敛 独立同分布 次线性期望
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Tumor response assessment by the single-lesion measurement per organ in small cell lung cancer 被引量:4
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作者 Soong Goo Jung Jung Han Kim +2 位作者 Hyeong Su Kim Kyoung Ju Kim Ik Yang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第2期161-167,共7页
Background: The criterion of two target lesions per organ in the Response Evaluation Criteria in Solid Tumors (RECIST) version I. 1 is an arbitrary one, being supported by no objective evidence. The optimal number ... Background: The criterion of two target lesions per organ in the Response Evaluation Criteria in Solid Tumors (RECIST) version I. 1 is an arbitrary one, being supported by no objective evidence. The optimal number of target lesions per organ still needs to be investigated. We compared tumor responses using the RECIST 1.1 (measuring two target lesions per organ) and modified RECIST I. 1 (measuring the single largest lesion in each organ) in patients with small cell lung cancer (SCLC). Methods: We reviewed medical records of patients with SCLC who received first-line treatment between January 2004 and December 2014 and compared tumor responses according to the two criteria using computed tomography. Results: There were a total of 34 patients who had at least two target lesions in any organ according to the RECIST 1.1 during the study period. The differences in the percentage changes of the sum of tumor measurements between RECIST 1.1 and modified RECIST 1.1 were all within 13%. Seven patients showed complete response and fourteen showed partial response according to the RECIST I.I. The overall response rate was 61.8%. When assessing with the modified RECIST 1.1 instead of the RECIST 1.1, tumor responses showed perfect concordance between the two criteria (k= 1.0). Conclusions: The modified RECIST 1.I showed perfect agreement with the original RECIST 1.I in the assessment of tumor response of SCLC. Our result suggests that it may be enough to measure the single largest target lesion per organ for evaluating tumor response. 展开更多
关键词 Target lesion Response Evaluation Criteria in Solid Tumors 1.1 (RECiST 1.1) modified Response Evaluation Criteria in Solid Tumors tumor response i.i (modified RECiST 1.1) small cell lung cancer (SCLC)
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一种用于主动磁轴承不平衡补偿的切换控制法 被引量:1
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作者 左曙光 罗莹 《机电产品开发与创新》 2023年第1期92-96,103,共6页
为了改善主动磁轴承转子在质量不平衡影响下的动力学性能,本文提出了一种基于I&I控制法和自适应陷波滤波器不平衡补偿切换控制方法。首先,本文考虑了转子的质量不平衡,建立了三极磁轴承转子系统的动力学模型。然后,本文分别设计了... 为了改善主动磁轴承转子在质量不平衡影响下的动力学性能,本文提出了一种基于I&I控制法和自适应陷波滤波器不平衡补偿切换控制方法。首先,本文考虑了转子的质量不平衡,建立了三极磁轴承转子系统的动力学模型。然后,本文分别设计了适用于该系统的I&I参数更新律、控制律及自适应陷波滤波器,并设计了合适的切换点,实现了对磁轴承不平衡转子的切换控制。仿真结果表明,该控制方法结合了I&I控制法的高精度和自适应陷波滤波器的低铜损优势,能够在保证转子振幅不超出安全范围的同时获得较低的能量损耗。 展开更多
关键词 主动磁轴承 不平衡补偿 切换控制 浸入与不变 自适应陷波滤波器
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Synthesis, crystal structure and properties of a samarium nitrate complex with 2-idobenzoic acid and 2,2'-bipyridine 被引量:3
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作者 雷智鸿 赵凯 +1 位作者 顾雅琨 李夏 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第4期303-307,共5页
A complex [Sm(2-IBA)2(2,2’-bipy)(NO3)]2 (2-HIBA=2-idobenzoic acid; 2,2’-bipy=2,2’-bipyridine) was synthesized by solvent method and characterized by X-ray single-crystal diffraction. The complex crystallize... A complex [Sm(2-IBA)2(2,2’-bipy)(NO3)]2 (2-HIBA=2-idobenzoic acid; 2,2’-bipy=2,2’-bipyridine) was synthesized by solvent method and characterized by X-ray single-crystal diffraction. The complex crystallized in triclinic crystal system, Pī space group, with a= 0.97873(3) nm, b=1.28124(3) nm, c=1.29174(3) nm, α=108.3740(10)o, β=111.7340(10)o, γ=101.7870(10)o. The complex was the centrosymmetric binuclear molecule, in which two Sm3+ ions were connected by four 2-IBA ligands. Two of the 2-IBA ligands were in a bidentate bridging mode and the other two were in a tridentate bridging mode. Sm3+ ion was also coordinated to one chelating NO3– group and one 2,2’-bipy molecule. The 2D supramolecular network formed through weak I…I interactions and π…π stacking interactions. The fluorescent emission peaks at 562, 595, and 642 nm corresponded to the 4G5/2→6F5/2, 4G5/2→6F7/2, and 4G5/2→6F9/2 transitions of Sm3+ ion, respectively. 展开更多
关键词 samarium complex 2-idobenoic acid crystal structure ii interaction fluorescence rare earths
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Precise Asymptotics in Chung's Law of the Iterated Logarithm 被引量:2
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作者 Li Xin ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第4期631-646,共16页
Let X, X1, X2,... be i.i.d, random variables with mean zero and positive, finite variance σ^2, and set Sn = X1 +... + Xn, n≥1. The author proves that, if EX^2I{|X|≥t} = 0((log log t)^-1) as t→∞, then for ... Let X, X1, X2,... be i.i.d, random variables with mean zero and positive, finite variance σ^2, and set Sn = X1 +... + Xn, n≥1. The author proves that, if EX^2I{|X|≥t} = 0((log log t)^-1) as t→∞, then for any a〉-1 and b〉 -1,lim ε↑1/√1+a(1/√1+a-ε)b+1 ∑n=1^∞(logn)^a(loglogn)^b/nP{max κ≤n|Sκ|≤√σ^2π^2n/8loglogn(ε+an)}=4/π(1/2(1+a)^3/2)^b+1 Г(b+1),whenever an = o(1/log log n). The author obtains the sufficient and necessary conditions for this kind of results to hold. 展开更多
关键词 the law of the iterated logarithm Chung's law of the iterated logarithm small deviation i.i.d random variables
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商用布草清洁的特点和生物酶应用简述 被引量:2
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作者 刘洋 高楠 刘奕彤 《中国洗涤用品工业》 CAS 2021年第1期41-44,共4页
商用布草清洁是现代社会不可或缺的公共服务,文章对于商用布草清洁的要求和特点进行了阐述,并解读了生物酶作为新技术在商用布草清洁中的优势和应用方法。
关键词 布草 洗净率 蛋白酶 脂肪酶 温和配方 纤维素酶 i&i
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Novel parametric optimum processing method for airborne radar 被引量:1
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作者 XUJia PENGYingning +3 位作者 WANQun ZHANGLiping LINYan XIAXianggen 《Science in China(Series F)》 2004年第6期706-716,共11页
In radar target detection, an optimum processor needs to automatically adapt its weights to the environment change. Conventionally, the optimum weights are obtained by substantial independently and identically distrib... In radar target detection, an optimum processor needs to automatically adapt its weights to the environment change. Conventionally, the optimum weights are obtained by substantial independently and identically distributed (i.i.d.) interference samplings, which is not always realistic in an inhomogeneous clutter background of airborne radar. The lack of i.i.d. samplings will inevitably lead to performance deterioration for optimum processing. In this paper, a novel parametric adaptive processing method is proposed for airborne radar target detection based on the modified Doppler distributed clutter (DDC) model with contribution of clutter's internal motion. It is different from the conventional methods in that the adaptive weights are determined by two parameters of DDC model, i.e., angular center and spread. A low-complexity nonlinear operators approach is also proposed to estimate these parameters. Simulation and performance analysis are also provided to show that the proposed method can remarkably reduce the dependence of i.i.d. samplings and it is computationally efficient for practical use. 展开更多
关键词 airborne radar adaptive implementation of optimum processing (AiOP) Doppler distributed clutter (DDC) mode independently and identically distributed (i.i.d.) sampling nonlinear energy operator (NLOP).
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Adjoining Batch Markov Arrival Processes of a Markov Chain 被引量:1
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作者 Xiao-yun MO Xu-yan XIANG Xiang-qun YANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2018年第1期1-10,共10页
A batch Markov arrival process(BMAP) X^*=(N, J) is a 2-dimensional Markov process with two components, one is the counting process N and the other one is the phase process J. It is proved that the phase process i... A batch Markov arrival process(BMAP) X^*=(N, J) is a 2-dimensional Markov process with two components, one is the counting process N and the other one is the phase process J. It is proved that the phase process is a time-homogeneous Markov chain with a finite state-space, or for short, Markov chain. In this paper,a new and inverse problem is proposed firstly: given a Markov chain J, can we deploy a process N such that the 2-dimensional process X^*=(N, J) is a BMAP? The process X^*=(N, J) is said to be an adjoining BMAP for the Markov chain J. For a given Markov chain the adjoining processes exist and they are not unique. Two kinds of adjoining BMAPs have been constructed. One is the BMAPs with fixed constant batches, the other one is the BMAPs with independent and identically distributed(i.i.d) random batches. The method we used in this paper is not the usual matrix-analytic method of studying BMAP, it is a path-analytic method. We constructed directly sample paths of adjoining BMAPs. The expressions of characteristic(D_k, k = 0, 1, 2· · ·)and transition probabilities of the adjoining BMAP are obtained by the density matrix Q of the given Markov chain J. Moreover, we obtained two frontal Theorems. We present these expressions in the first time. 展开更多
关键词 Markov chain batch Markov arrival process (BMAP) adjoining BMAP fixed constant batch independent identically distributed i.i.d) random batch
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On the Relationship Between the Baum-Katz-Spitzer Complete Convergence Theorem and the Law of the Iterated Logarithm
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作者 De Li LI Andrew ROSALSKY Andrei VOLODIN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第4期599-612,共14页
For a sequence of i.i.d. Banach space-valued random variables {Xn; n ≥ 1} and a sequence of positive constants {an; n ≥ 1}, the relationship between the Baum-Katz-Spitzer complete convergence theorem and the law of ... For a sequence of i.i.d. Banach space-valued random variables {Xn; n ≥ 1} and a sequence of positive constants {an; n ≥ 1}, the relationship between the Baum-Katz-Spitzer complete convergence theorem and the law of the iterated logarithm is investigated. Sets of conditions are provided under which (i) lim sup n→∞ ||Sn||/an〈∞ a.s.and ∞ ∑n=1(1/n)P(||Sn||/an ≥ε〈∞for all ε 〉 λ for some constant λ ∈ [0, ∞) are equivalent;(ii) For all constants λ ∈ [0, ∞),lim sup ||Sn||/an =λ a.s.and ^∞∑ n=1(1/n) P(||Sn||/an ≥ε){〈∞, if ε〉λ =∞,if ε〈λare equivalent. In general, no geometric conditions are imposed on the underlying Banach space. Corollaries are presented and new results are obtained even in the case of real-valued random variables. 展开更多
关键词 partial sums of i.i.d. Banach space-valued random variables Baum-Katz-Spitzer complete convergence theorem law of the iterated logarithm almost sure convergence
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Distribution of the Maximum and Minimum of a Random Number of Bounded Random Variables
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作者 Jie Hao Anant Godbole 《Open Journal of Statistics》 2016年第2期274-285,共12页
We study a new family of random variables that each arise as the distribution of the maximum or minimum of a random number N of i.i.d. random variables X<sub>1</sub>, X<sub>2</sub>,…, X<sub... We study a new family of random variables that each arise as the distribution of the maximum or minimum of a random number N of i.i.d. random variables X<sub>1</sub>, X<sub>2</sub>,…, X<sub>N</sub>, each distributed as a variable X with support on [0, 1]. The general scheme is first outlined, and several special cases are studied in detail. Wherever appropriate, we find estimates of the parameter θ in the one-parameter family in question. 展开更多
关键词 Maximum and Minimum Random Number of i.i.d. Variables Statistical inference
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On the Rates of the Other Law of the Logarithm
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作者 Li-Xin ZHANG You-You CHEN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第4期781-792,共12页
Let X, X1, X2,… be i.i.d, random variables, and set Sn =X1+…+Xn,Mn=maxk≤n|Sk|,n≥1.Let an=o(√log n).By using the strong approximation, we prove that, if EX = 0,
关键词 Complete convergence tail probabilities of sums of i.i.d random variables the other lawof the logarithm strong approximation
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Random Stabilization of Sampled-data Control Systems with Nonuniform Sampling
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作者 Bin Tang Qi-Jie Zeng De-Feng He Yun Zhang School of Automation, Guangdong University of Technology, Guangzhou 510006, China 《International Journal of Automation and computing》 EI 2012年第5期492-500,共9页
For a sampled-data control system with nonuniform sampling, the sampling interval sequence, which is continuously distributed in a given interval, is described as a multiple independent and identically distributed (i.... For a sampled-data control system with nonuniform sampling, the sampling interval sequence, which is continuously distributed in a given interval, is described as a multiple independent and identically distributed (i.i.d.) process. With this process, the closed-loop system is transformed into an asynchronous dynamical impulsive model with input delays. Sufficient conditions for the closed-loop mean-square exponential stability are presented in terms of linear matrix inequalities (LMIs), in which the relation between the nonuniform sampling and the mean-square exponential stability of the closed-loop system is explicitly established. Based on the stability conditions, the controller design method is given, which is further formulated as a convex optimization problem with LMI constraints. Numerical examples and experiment results are given to show the effectiveness and the advantages of the theoretical results. 展开更多
关键词 Sampled-data control system nonuniform sampling independent and identically distributed (i.i.d.) process mean-square exponential stability controller design
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A Supplement to the Baum-Katz-Spitzer Complete Convergence Theorem
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作者 Andrew ROSALSKY 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第3期557-562,共6页
Let {X, Xn; n≥ 1} be a sequence of i.i.d. Banach space valued random variables and let {an; n ≥ 1} be a sequence of positive constants such thatan↑∞ and 1〈 lim inf n→∞ a2n/an≤lim sup n→∞ a2n/an〈∞Set Sn=∑i... Let {X, Xn; n≥ 1} be a sequence of i.i.d. Banach space valued random variables and let {an; n ≥ 1} be a sequence of positive constants such thatan↑∞ and 1〈 lim inf n→∞ a2n/an≤lim sup n→∞ a2n/an〈∞Set Sn=∑i=1^n Xi,n≥1.In this paper we prove that∑n≥1 1/n P(||Sn||≥εan)〈∞ for all ε〉0if and only if lim n→∞ Sn/an=0 a.s. This result generalizes the Baum-Katz-Spitzer complete convergence theorem. Combining our result and a corollary of Einmahl and Li, we solve a conjecture posed by Gut. 展开更多
关键词 partial sums of i.i.d. Banach space valued random variables Baum-Katz-Spitzer complete convergence theorem almost sure convergence
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Convergence in Law to Operator Fractional Brownian Motion of Riemann-Liouville Type
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作者 Hong Shuai DAI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2013年第4期777-788,共12页
In this paper, we extend the well-studied fractional Brownian motion of Riemann-Liouville type to the multivariate case, and the corresponding processes are called operator fractional Brownian motions of Riemann-Liouv... In this paper, we extend the well-studied fractional Brownian motion of Riemann-Liouville type to the multivariate case, and the corresponding processes are called operator fractional Brownian motions of Riemann-Liouville type. We also provide two results on approximation to operator fractional Brownian motions of Riemann-Liouville type. The first approximation is based on a Poisson process, and the second one is based on a sequence of I.I.D. random variables. 展开更多
关键词 Operator fractional Brownian motion of Riemann-Liouville type Poisson process a se-quence of i.i.D. random variables weak convergence
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邻域数的依概率ρ——级发散性
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作者 游荣彦 《华南师范大学学报(自然科学版)》 CAS 1992年第1期111-115,共5页
本文先提出了随机变量序列依概率ρ一级发散的概念,讨论了这种发散与通常的依概率发散的关系;在第二节,定义了一个d一维总体的邻域数,并给出了它作为一维离散型随机变量依概率ρ一级发散的条件,该条件不依赖于总体的分布,因此定理对一... 本文先提出了随机变量序列依概率ρ一级发散的概念,讨论了这种发散与通常的依概率发散的关系;在第二节,定义了一个d一维总体的邻域数,并给出了它作为一维离散型随机变量依概率ρ一级发散的条件,该条件不依赖于总体的分布,因此定理对一切总体均成立. 展开更多
关键词 随机变量序列 邻域数 依概率ρ-级发散性
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基于α混合序列的在线算法的推广性能(英文)
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作者 胡小云 邹斌 +1 位作者 龚铁梁 杨艳 《工程数学学报》 CSCD 北大核心 2017年第2期209-220,共12页
近年来,在线算法的理论研究得到相应的重视.以前在线算法的推广界都是基于独立同分布的样本建立的.在本文中,我们跳过这个框架来研究基于α混合序列的在线算法的推广界.我们用全变差来定义α混合序列,而且在分析时只要求鞅收敛参数.结果... 近年来,在线算法的理论研究得到相应的重视.以前在线算法的推广界都是基于独立同分布的样本建立的.在本文中,我们跳过这个框架来研究基于α混合序列的在线算法的推广界.我们用全变差来定义α混合序列,而且在分析时只要求鞅收敛参数.结果是:"遗憾"可以度量在线算法的性能.与β混合序列比较,我们得到更紧的推广误差估计. 展开更多
关键词 在线算法 独立同分布的样本 α混合 推广界
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三角组列完全收敛性的注记
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作者 陆凤彬 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2005年第2期144-147,共4页
设{ Xi,i≥1}为独立同分布或m -相依的平稳随机变量序列,h为R^2→R的实可测函数.考虑三角组列{ h(Xi,Xn) ,i<n,n>1} ,利用Fubini定理,得到其部分和的完全收敛性,推广了DEHL ING、邓学斌等和蔡小云的结果。
关键词 三角组列 完全收敛性 独立同分布 m-相依
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