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不动点定理理论在高考数列中的应用
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作者 孔伟铭 《中华少年》 2018年第23期195-196,共2页
本文首先介绍了不动点理论的相关背景知识,然后简述了不动点定理的迭代思想,并以此来研究递推数列的通项以及证明数列的有界性,并借此解决一些高考题,希望借此能帮助学术更好的理解这一知识点,从而有助于更顺利解题。
关键词 递推数列 不动点 定理理论
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有限位移理论线弹性动力学二类和三类混合变量的最小势作用量原理和驻值余作用量原理及其应用 被引量:2
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作者 付宝连 《应用数学和力学》 CSCD 北大核心 2017年第12期1359-1376,共18页
两个新的概念,即势作用量的概念和余作用量的概念被引入弹性动力学变分原理中.根据势作用量的概念,最小作用量原理(即Hamilton原理)被改称为最小势作用量原理.根据余作用量的概念,首次提出了驻值余作用量原理.考虑边界条件的变化并应用... 两个新的概念,即势作用量的概念和余作用量的概念被引入弹性动力学变分原理中.根据势作用量的概念,最小作用量原理(即Hamilton原理)被改称为最小势作用量原理.根据余作用量的概念,首次提出了驻值余作用量原理.考虑边界条件的变化并应用有限位移理论的功的互等定理,导出了以位移和应力为变分变量的二类混合变量的最小势作用量原理及驻值余作用量原理.应用应变势能密度与应力余能密度的关系式于上述二类混合变量作用量原理,导出了以位移、应力和应变为变分变量的三类混合变量的相关作用量原理.最后,应用拉氏乘子法给出了广义势作用量原理及广义余作用量原理,并且应用大挠度梁二类混合变量最小势作用量原理计算了一悬臂梁的受迫振动. 展开更多
关键词 势作用量 余作用量 有限位移理论的功的互等定理 二类(三类)混合变量最小势作用量原理 二类(三类)混合变量驻值余作用量原理
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一个具有时滞的广义的捕食者-食饵系统正周期解的存在性(英文) 被引量:1
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作者 吴新民 李经文 《黑龙江大学自然科学学报》 CAS 北大核心 2006年第4期512-518,共7页
运用不等式技巧,获得了广义捕食者-食饵系统的先验估计,应用重合度理论的延拓定理,导出了一个具有时滞的广义的捕食者-食饵系统正周期解的存在性准则.
关键词 广义的捕食者-食饵系统 正周期解 时滞 重合度理论的延拓定理
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~ Transform Demonstration of Dark Soliton Solutions Found by Inverse Scattering 被引量:2
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作者 LI Cun YANG Bai-Feng CAI Hao HUANG Nian-Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期244-248,共5页
One of the basic problems about the inverse scattering transform for solving a completely integrable nonlinear evolutions equation is to demonstrate that the Jost solutions obtained from the inverse scattering equatio... One of the basic problems about the inverse scattering transform for solving a completely integrable nonlinear evolutions equation is to demonstrate that the Jost solutions obtained from the inverse scattering equations of Cauchy integral satisfy the Lax equations. Such a basic problem still exists in the procedure of deriving the dark soliton solutions of the NLS equation in normal dispersion with non-vanishing boundary conditions through the inverse scattering transform. In this paper, a pair of Jost solutions with same analytic properties are composed to be a 2 × 2 matrix and then another pair are introduced to be its right inverse confirmed by the Liouville theorem. As they are both 2 × 2 matrices, the right inverse should be the left inverse too, based upon which it is not difficult to show that these Jost solutions satisfy both the first and second Lax equations. As a result of compatibility condition, the dark soliton solutions definitely satisfy the NLS equation in normal dispersion with non-vanishing boundary conditions. 展开更多
关键词 inverse scattering transform dark soliton solultions Liouville theorem
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Benford's Law and β-Decay Half-Lives 被引量:1
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作者 NI Dong-Dong WEI Lai REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期713-716,共4页
The experimental values of 2059 β-decay half-lives are systematically analyzed and investigated. We have found that they are in satisfactory agreement with Benford's law, which states that the frequency of occurrenc... The experimental values of 2059 β-decay half-lives are systematically analyzed and investigated. We have found that they are in satisfactory agreement with Benford's law, which states that the frequency of occurrence of each figure, 1-9, as the first significant digit in a surprisingly large number of different data sets follows a logarithmic distribution favoring the smaller ones. Benford's logarithmic distribution of β-deeay half-lives can be explained in terms of Neweomb's justification of Benford's law and empirical exponential law of β-decay half-lives. Moreover, we test the calculated values of 6721 β-decay half-lives with the aid of Benford's law. This indicates that Benford's law is useful for theoretical physicists to test their methods for calculating β-decay half-lives. 展开更多
关键词 Benford's law β-decay HALF-LIVES
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一类随机离散Logistic时滞方程的渐近稳定性(英文)
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作者 吴小花 廖新元 葛玲玲 《数学理论与应用》 2015年第3期23-29,共7页
本文提出了一类Logistic时滞模型的随机离散形式,并对其进行了研究.首先,讨论了相对应的确定性离散模型的稳定解.其次,在一些简单的条件下,证明了随机离散Logistic方程的渐近稳定性.最后,利用数值仿真说明了主要结果.
关键词 随机稳定 Logistic差分方程 时滞Lyapunov理论鞅收敛定理
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Generalized Uncertainty Principle and Black Hole Entropy of Higher-Dimensional de Sitter Spacetime 被引量:1
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作者 ZHAO Hai-Xia LI Huai-Fan +1 位作者 HU Shuang-Qi ZHAO Ren 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期465-468,共4页
Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-- Hawking black hole entropy. In particular, many researchers have expressed a vested interest in the coetticient ... Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-- Hawking black hole entropy. In particular, many researchers have expressed a vested interest in the coetticient of the logarithmic term of the black hole entropy correction term. In this paper, we calculate the correction value of the black hole entropy by utilizing the generalized uncertainty prlnciple and obtain the correction term caused by the generalized uncertainty principle. Because in our calculation we think that the Bekenstein-Hawking area theorem is still valid after considering the generalized uncertainty principle, we derive that the coefficient of the logarithmic term of the black hole entropy correction term is positive. This result is different from the known result at present. Our method is valid not only for four-dimensional spacetimes but also for higher-dimensional spacetimes. In the whole process, the physics idea is clear and calculation is simple. It offers a new way for studying the entropy correction of the complicated spacetime. 展开更多
关键词 generalized uncertainty principle black hole entropy area theorem higher-dimensional spacetime
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On a Generalization of Some Restrictive Distribution Theorems
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作者 田震 张松 《Chinese Quarterly Journal of Mathematics》 CSCD 1995年第3期78-85,共8页
This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set... This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set of every box is Now,place the n balls into the m boxes. Thenumber of distinct placed ways is expressed by , and simply by And it is called the distribution number.Main result is:Theorem The exponential generating function of sequence isThus .there is the recurrence relationhere (integer set). 展开更多
关键词 the distribution of Ⅰtype exponential generating function COMBINATORICS
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A Note on Orthogonal Multiplication
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作者 田立根 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第3期91-93,共3页
Hurewicz-Radon theorem [1] gives a sufficient and necessary condition about the existence of an orthogonal multiplication f:Rk×Rn→Rn. In this paper,we shall discuss two extensions of the theorem.that is,the suff... Hurewicz-Radon theorem [1] gives a sufficient and necessary condition about the existence of an orthogonal multiplication f:Rk×Rn→Rn. In this paper,we shall discuss two extensions of the theorem.that is,the sufficient and necessary conditions about the existence of an orthogonal multiplication f:Rk×Rn→Rn+1or f:Rk×Rn→Rn+2 展开更多
关键词 orthogonal multiplication Hurewicz-Radon theorem topological K-theory
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AN INTRUSION DETECTION SYSTEM BASED ON EVIDENCE THEORY AND ROUGH SET THEORY 被引量:2
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作者 Ye Qing Wu Xiaoping Zhang Changhong 《Journal of Electronics(China)》 2009年第6期777-781,共5页
In this paper,we propose a novel Intrusion Detection System (IDS) architecture utilizing both the evidence theory and Rough Set Theory (RST). Evidence theory is an effective tool in dealing with uncertainty question. ... In this paper,we propose a novel Intrusion Detection System (IDS) architecture utilizing both the evidence theory and Rough Set Theory (RST). Evidence theory is an effective tool in dealing with uncertainty question. It relies on the expert knowledge to provide evidences,needing the evidences to be independent,and this make it difficult in application. To solve this problem,a hybrid system of rough sets and evidence theory is proposed. Firstly,simplification are made based on Variable Precision Rough Set (VPRS) conditional entropy. Thus,the Basic Belief Assignment (BBA) for all evidences can be calculated. Secondly,Dempster’s rule of combination is used,and a decision-making is given. In the proposed approach,the difficulties in acquiring the BBAs are solved,the correlativity among the evidences is reduced and the subjectivity of evidences is weakened. An illustrative example in an intrusion detection shows that the two theories combination is feasible and effective. 展开更多
关键词 Intrusion Detection System (IDS) Evidence theory Rough Set Theory (RST)
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Entire functions sharing a value with its weight
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作者 段曦盛 《Journal of Chongqing University》 CAS 2003年第2期91-93,共3页
A uniqueness theorem for entire functions sharing one finite complex value with weight two is proved by using Nevanlinna theory , and this improves the result of Fang and Hua.
关键词 entire function sharing value unicity
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The Q theory of investment, the capital asset pricing model,and asset valuation: a synthesis
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作者 MCDONALDJohnF. 《Journal of Zhejiang University Science》 CSCD 2004年第5期499-508,共10页
The paper combines Tobin's Q theory of real investment with the capital asset pricing model to produce a new and relatively simple procedure for the valuation of real assets using the income approach. Applications... The paper combines Tobin's Q theory of real investment with the capital asset pricing model to produce a new and relatively simple procedure for the valuation of real assets using the income approach. Applications of the new method are provided. 展开更多
关键词 Investment theory Asset pricing APPRAISAL
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Fuzzy robust sliding mode control of a class of uncertain systems 被引量:6
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作者 REN Li-tong 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2296-2304,共9页
Aiming at a class of systems under parameter perturbations and unknown external disturbances, a method of fuzzy robust sliding mode control was proposed. Firstly, an integral sliding mode surface containing state feed... Aiming at a class of systems under parameter perturbations and unknown external disturbances, a method of fuzzy robust sliding mode control was proposed. Firstly, an integral sliding mode surface containing state feedback item was designed based on robust H∞ control theory. The robust state feedback control was utilized to substitute for the equivalent control of the traditional sliding mode control. Thus the robustness of systems sliding mode motion was improved even the initial states were unknown. Furthermore, when the upper bound of disturbance was unknown, the switching control logic was difficult to design, and the drawbacks of chattering in sliding mode control should also be considered simultaneously. To solve the above-mentioned problems, the fuzzy nonlinear method was applied to approximate the switching control term. Based on the Lyapunov stability theory, the parameter adaptive law which could guarantee the system stability was devised. The proposed control strategy could reduce the system chattering effectively. And the control input would not switch sharply, which improved the practicality of the sliding mode controller. Finally, simulation was conducted on system with parameter perturbations and unknown external disturbances. The result shows that the proposed method could enhance the approaching motion performance effectively. The chattering phenomenon is weakened, and the system possesses stronger robustness against parameter perturbations and external disturbances. 展开更多
关键词 uncertain systems robust control fuzzy sliding mode control CHATTERING
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(Anti-)de Sitter Black Hole Entropy and Generalized Uncertainty Principle
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作者 ZHAO Ren ZHANG Li-Chun HU Shuang-Qi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期635-638,共4页
We generalize the method that is used to study corrections to Cardy-Verlinde formula due to generalized uncertainty principle and discuss corrections to Cardy-Verlinde formula due to generalized uncertainty principle ... We generalize the method that is used to study corrections to Cardy-Verlinde formula due to generalized uncertainty principle and discuss corrections to Cardy-Verlinde formula due to generalized uncertainty principle in (anti)- de Sitter space. Because in de Sitter black hole spacetime the radiation temperature of the black hole horizon is different from the one of the cosmological horizon, this spacetime is a thermodynamical non-equilibrium spacetime. 展开更多
关键词 entropy correction generalized uncertainty principle non-equilibrium spacetime
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Existence of Two Periodic Solutions of a Delayed Single Species Model with Feedback Regulation and Harvest Term 被引量:1
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作者 TIAN De-sheng CAI Guang-xing YANG Ce-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期407-413,共7页
By means of the continuation theorem of the coincidence degree theory,the existence of two periodic solutions of a delayed single species model with feedback regulation and harvest term is obtained.
关键词 two periodic solutions delayed single-species model feedback regulation and harvest term continuation theorem of the coincidence degree theory
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Synchronization of perturbed chaotic systems via nonlinear control
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作者 郭凌 年晓红 潘欢 《Journal of Central South University》 SCIE EI CAS 2012年第10期2803-2809,共7页
Chaos synchronization of systems with perturbations was investigated.A generic nonlinear control scheme to realize chaos synchronization of systems was proposed.This control scheme is flexible and practicable,and give... Chaos synchronization of systems with perturbations was investigated.A generic nonlinear control scheme to realize chaos synchronization of systems was proposed.This control scheme is flexible and practicable,and gives more freedom in designing controllers in order to achieve some desired performance.With the aid of Lyapunov stability theorem and partial stability theory,two cases were presented:1) Chaos synchronization of the system without perturbation or with vanishing perturbations;2) The boundness of the error state for the system with nonvanishing perturbations satisfying some conditions.Finally,several simulations for Lorenz system were provided to verify the effectiveness and feasibility of our method.Compared numerically with the existing results of linear feedback control scheme,the results are sharper than the existing ones. 展开更多
关键词 chaotic system SYNCHRONIZATION PERTURBATIONS nonlinear control scheme linear feedback scheme
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A Reliability Analysis of Calculated Results for Odd-Even and Odd-Odd Nuclei in Relativistic Mean-Field Theory
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作者 DING Bin-Gang ZHANG Da-Li LU Ding-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期113-118,共6页
We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nu... We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nuclei and odd-odd nuclei. We find that the errors of binding energy of odd-even and odd-odd nuclei are not bigger than the one of even-even nuclei. The result shows that comparing with even-even nuclei, there is no systematic error and approximation in the calculations of the binding energy of odd-even and odd-odd nuclei with relativistic mean-field theory. In addition, the result is explained theoretically. 展开更多
关键词 relativistic mean-field theory binding energy even-even nuclei odd-even nuclei odd-odd nuclei
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A Note of Spirallike Mappings in C^n
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作者 李小申 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第1期52-54, ,共3页
In this paper,the Growth and covering Theorems for a kind of spirallike mapping are given.
关键词 spirallike mappings Growth Theorems normal matrix
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A New View on Teaching Motivation Self-determination Theory
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作者 MA Wen-ying LIU Xi 《Sino-US English Teaching》 2016年第1期33-39,共7页
Self-determination Theory categorises motivation into three broad types: amotivation, extrinsic motivation, and intrinsic motivation according to the level of self-determination. This theory argues that people's mot... Self-determination Theory categorises motivation into three broad types: amotivation, extrinsic motivation, and intrinsic motivation according to the level of self-determination. This theory argues that people's motivation is a developmental process across time and place. Furthermore, it emphasizes that three basic psychological needs--a need for competence, a need for autonomy, and a need for relatedness--are the nutriments of motivation. Thus, as this theory not only concerns the type of motivation, but also the circumstances that promote and maintain motivation, it offers insight to the nature of lecturers' motivation. It is claimed to be one of the most influential theories in contemporary motivation psychology 展开更多
关键词 new view teaching motivation self-determination theory
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Educational Situation: Some Preliminary Remarks on a Basic Concept of Education Studies
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作者 Thomas Altfelix 《Journal of Philosophy Study》 2013年第7期634-650,共17页
When educationalists are asked to define their own academic discipline of Education Studies, they often struggle to reach a common understanding. From an epistemological point of view, this indeterminacy leads back to... When educationalists are asked to define their own academic discipline of Education Studies, they often struggle to reach a common understanding. From an epistemological point of view, this indeterminacy leads back to the complex considerations involved in establishing a basic concept of education. In this article, the author explores in a preliminary fashion the possibility of identifying the essence of education in its performativity as an occurrence in context that always precedes and supersedes our theoretical considerations of it. Education is not to be understood primarily as something conceptual (theory) but rather in terms of its significance as a situational event (reality). Educational reality thus informs educational theory and this relationship implies a knowledge-ethical surplus of the former as an inexhaustible source for the latter. 展开更多
关键词 educational theory educational studies educational situation basic concept
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