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Lottery Numbers and Ordered Statistics
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作者 Kung-Kuen Tse 《Applied Mathematics》 2024年第4期287-291,共5页
The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typica... The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typically random and unpredictable. Some people use the lottery terminal randomly generates numbers for them, some players choose numbers that hold personal significance to them, such as birthdays, anniversaries, or other important dates, some enthusiasts have turned to statistical analysis as a means to analyze past winning numbers identify patterns or frequencies. In this paper, we use order statistics to estimate the probability of specific order of numbers or number combinations being drawn in future drawings. 展开更多
关键词 LOTTERY order Statistics Hypergeometric Distribution EXPECTATION uniform
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Second-Order Solutions for Random Interfacial Waves Under Steady Uniform Currents 被引量:3
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作者 宋金宝 《China Ocean Engineering》 SCIE EI 2005年第2期333-338,共6页
In the present research, the study of Song (2004) for random interfacial waves in two-layer fluid is extended to the case of fluids moving at different steady uniform speeds. The equations describing the random displa... In the present research, the study of Song (2004) for random interfacial waves in two-layer fluid is extended to the case of fluids moving at different steady uniform speeds. The equations describing the random displacements of the density interface and the associated velocity potentials in two-layer fluid are solved to the second order, and the wave-wave interactions of the wave components and the interactions between the waves and currents are described. As expected, the extended solutions include those obtained by Song (2004) as one special case where the steady uniform currents of the two fluids are taken as zero, and the solutions reduce to those derived by Sharma and Dean (1979) for random surface waves if the density of the upper fluid and the current of the lower fluid are both taken as zero. 展开更多
关键词 two-layer fluid uniform current random interfacial waves second-order solutions
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A UNIFORM HIGH-ORDER METHOD FOR A SINGULAR PERTURBATION PROBLEM IN CONSERVATIVE FORM
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作者 吴启光 孙晓弟 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第10期909-916,共8页
A uniform high-order method is. presented for the numerical solution of a singular perturbation problem in conservative form. We firest replace the original second-order problem (1.1) by two equivalent first-order pro... A uniform high-order method is. presented for the numerical solution of a singular perturbation problem in conservative form. We firest replace the original second-order problem (1.1) by two equivalent first-order problems ( 1.4), i.e., the solution of (1.1) is a linear combination of the solutions of (1.4). Then we derive a uniformly O (hm+1) accurate scheme for the first-order problems (1.4), where m is an arbitrary nonnegative integer, so we can get a uniformly O (hm+1) accurate solution of the original problem (1.1) by relation (1.3). Some illustrative numerical results are also given. 展开更多
关键词 uniform high-order method singular perturbation problem initial value problem
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A UNIFORMLY CONVERGENT SECOND ORDER DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED SELF-ADJOINT ORDINARY DIFFERENTIAL EQUATION IN CONSERVATION FORM
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作者 郭雯 林鹏程 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第3期231-241,共11页
In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniform... In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniformly convergent second order scheme. 展开更多
关键词 exp A uniformLY CONVERGENT SECOND order DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED SELF-ADJOINT ORDINARY DIFFERENTIAL EQUATION IN CONSERVATION FORM
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BOUNDEDNESS AND UNIFORM BOUNDEDNESS RESULTS FOR CERTAIN NON-AUTONOMOUS DIFFERENTIAL EQUATIONS OF FOURTH ORDER
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作者 Cemil Tunc(西密尔·通兹) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第11期1273-1278,共6页
Sufficient conditions have been obtained so that all solutions of a different fourth order differential equation are bounded and uniformly bounded.
关键词 differential equation of fourth order Liapunov function BOUNDEDNESS uniform boundedness
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UNIFORM DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED LINEAR 2ND ORDER HYPERBOLIC PROBLEM WITH ZEROTH ORDER REDUCED EQUATION
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作者 苏煜城 林平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第4期301-313,共13页
In this paper a singularly perturbed linear second order hyperbolic problem with zeroth order reduced equation is discussed. Firstly, an energy inequality of the solution and an estimate of the remainder term of the a... In this paper a singularly perturbed linear second order hyperbolic problem with zeroth order reduced equation is discussed. Firstly, an energy inequality of the solution and an estimate of the remainder term of the asymptotic solution are given. Then an exponentially fitted difference scheme is developed in an equidistant mesh. Finally, uniform convergence in small parameter is proved in the sense of discrete energy norm. 展开更多
关键词 uniform DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED LINEAR 2ND order HYPERBOLIC PROBLEM WITH ZEROTH order REDUCED EQUATION
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Global Existence,Asymptotic Behavior and Uniform Attractors for a Third Order in Time Dynamics
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作者 曹洁 《Chinese Quarterly Journal of Mathematics》 2016年第3期221-236,共16页
In this paper, a third order(in time) partial differential equation in R^n is con-sidered. By using semigroup method and constructing Lyapunov function, we establish the global existence, asymptotic behavior and uni... In this paper, a third order(in time) partial differential equation in R^n is con-sidered. By using semigroup method and constructing Lyapunov function, we establish the global existence, asymptotic behavior and uniform attractors in nonhomogeneous case. In addition, we also obtain the results of well-uosedness in semilinear case. 展开更多
关键词 third order in time dynamics WELL-POSEDNESS asymptotic behavior uniform attractors
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高阶精度非线性加权格式权函数研究综述
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作者 毛枚良 白进维 +2 位作者 闵耀兵 马燕凯 江定武 《空气动力学学报》 CSCD 北大核心 2024年第6期1-14,I0001,共15页
在简述用于捕捉间断的非线性格式发展历程的基础上,依托五阶精度WENO格式,介绍了非线性加权格式在候选模板集选取、光滑度指标计算方法及其与非线性权的函数关系等方面做出的努力。对于非等宽候选模板集的情况,给出了保证非线性加权格... 在简述用于捕捉间断的非线性格式发展历程的基础上,依托五阶精度WENO格式,介绍了非线性加权格式在候选模板集选取、光滑度指标计算方法及其与非线性权的函数关系等方面做出的努力。对于非等宽候选模板集的情况,给出了保证非线性加权格式精度的非线性权的量阶关系,强调了光滑度指标计算方法对格式精度和效率的重要性,提出了进一步开展多宽度模板集非线性加权格式研究的建议。 展开更多
关键词 高阶精度非线性格式 非线性加权方法 极值点降阶问题 非等宽候选模板集 计算流体力学
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论我国刑法中的“保全型”自救行为
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作者 罗雨荔 《东北大学学报(社会科学版)》 北大核心 2024年第4期121-129,共9页
我国刑法中有保留“保全型”自救行为的余地,但不应直接照搬德国模式的理论建构。如果权利人保全手段涉及伤害、拘禁等限制、拘束义务人人身的罪名,并不需要也并不能够适用“保全型”自救行为;若相应手段涉及的是故意毁坏财物罪,当该行... 我国刑法中有保留“保全型”自救行为的余地,但不应直接照搬德国模式的理论建构。如果权利人保全手段涉及伤害、拘禁等限制、拘束义务人人身的罪名,并不需要也并不能够适用“保全型”自救行为;若相应手段涉及的是故意毁坏财物罪,当该行为确属保全权利过程中的必要行为时,在涉案金额相对权利标的额仍属轻微的情况下,可适用“保全型”自救行为。权利人以私自取走、扣押义务人财物或收集义务人个人信息的方式保全权利的案件,都有适用“保全型”自救行为阻却违法性的余地。前者依《民法典》第1 177条应以立即请求有关国家机关处理为其成立要件,后者则不应受其拘束。 展开更多
关键词 自救行为 违法阻却 私力救济 权利行使 法秩序统一性
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高度有序ZIF-8/Au纳米复合结构阵列的构筑及其表面增强拉曼光谱的应用
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作者 马亮 张洪华 +3 位作者 郑唯璐 游奥骐 欧阳志勇 曹俊江 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1743-1754,共12页
采用气-液界面自组装方式制备得到有序单层聚苯乙烯(PS)微球阵列,以此为模板,采用磁控溅射沉积方法结合热处理技术获得单层六方非密排Au纳米颗粒阵列。随后采用水热法成功制得高度有序ZIF-8/Au纳米复合结构有序阵列。探究了生长机理以... 采用气-液界面自组装方式制备得到有序单层聚苯乙烯(PS)微球阵列,以此为模板,采用磁控溅射沉积方法结合热处理技术获得单层六方非密排Au纳米颗粒阵列。随后采用水热法成功制得高度有序ZIF-8/Au纳米复合结构有序阵列。探究了生长机理以及反应温度、反应时间对微观形貌和光学特性的影响,进一步探究了该复合结构阵列作为表面增强拉曼散射(SERS)活性基底的灵敏度和均一性。结果表明:当水热反应温度从25℃升高至100℃时,ZIF-8纳米颗粒的数量逐步增多,同时尺寸随之增大,表面等离激元共振(SPR)峰和衍射峰均发生了红移。当水热反应时间从10 min增至60 min时,ZIF-8纳米颗粒从围绕Au纳米颗粒选择性生长到蔓延至整个材料表面。在样品表面沉积特定厚度的Ag膜后,测得4-氨基苯硫酚(4-ATP)和罗丹明6G(R6G)两种探针分子的检测极限均为10-11mol·L^(-1),4-ATP和R6G的SERS强度与分子溶液浓度呈线性关系,相关系数R2分别为0.9801和0.9844。随机选取10个不同位置测试4-ATP的SERS谱图,得到相对标准偏差(RSD)为8.86%,表明ZIF-8/Au纳米复合结构有序阵列作为SERS基底具有良好的均匀性和稳定性。 展开更多
关键词 ZIF-8/Au纳米复合结构有序阵列 有序性 表面增强拉曼散射 均一性
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非均匀散粒粗糙床面明渠紊流特性研究
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作者 徐翔宇 钟亮 +1 位作者 李国际 阎鑫铭 《中国农村水利水电》 北大核心 2024年第3期137-142,共6页
为揭示非均匀散粒粗糙床面明渠紊流特性,采用d_1=1.0 cm、d_2=1.5 cm的正方体散粒制成粗糙床面开展PIV水槽明渠紊流试验,探讨了紊动强度、速度高阶矩、雷诺应力和紊动能的分布规律。结果表明:(1)粒间区中部,邻近剖面颗粒的绕流作用使紊... 为揭示非均匀散粒粗糙床面明渠紊流特性,采用d_1=1.0 cm、d_2=1.5 cm的正方体散粒制成粗糙床面开展PIV水槽明渠紊流试验,探讨了紊动强度、速度高阶矩、雷诺应力和紊动能的分布规律。结果表明:(1)粒间区中部,邻近剖面颗粒的绕流作用使紊动强度发生明显变化。(2)速度高阶矩纵向偏度系数S_(u')与垂向偏度系数S_(v')的分布特性揭示在近床处主要发生扫掠事件,而颗粒顶部以上区域喷射事件占主导。(3)平均雷诺应力R_(mean)在粒间区沿程先增大再减小,在颗粒区先减小后增大。(4)紊动能呈条带状分布,在河床底部和水面受到的抑制使得整体紊动能从床面开始增大,在颗粒顶部附近达到最大之后开始减小。 展开更多
关键词 非均匀散粒粗糙 明渠紊流 紊动强度 速度高阶矩 雷诺应力 紊动能
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基于部分均匀采样的蒙特卡洛仿真模型
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作者 汤琦 孟贤 《光通信技术》 北大核心 2024年第5期86-90,共5页
针对海面紫外光散射传输中存在的衰减问题,提出了一种基于部分均匀采样的蒙特卡洛仿真模型。该模型考虑到海平面上空气中的粒子浓度较高导致能见度较低的情况,对距离参数采用重要性采样方法,而对方向参数中的天顶角则采用均匀采样方法... 针对海面紫外光散射传输中存在的衰减问题,提出了一种基于部分均匀采样的蒙特卡洛仿真模型。该模型考虑到海平面上空气中的粒子浓度较高导致能见度较低的情况,对距离参数采用重要性采样方法,而对方向参数中的天顶角则采用均匀采样方法。仿真结果表明:与传统的蒙特卡洛仿真模型相比,在保证相同性能的前提下,所提出的模型能够显著提高计算效率,计算效率提升了约5个数量级,非常适合应用于海上千米量级的实际传输场景。 展开更多
关键词 紫外光通信 多阶散射模型 蒙特卡洛 重要性采样 部分均匀采样 非视距通信
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The Distribution of the Concentration Ratio for Samples from a Uniform Population
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作者 Giovanni Girone Antonella Nannavecchia 《Applied Mathematics》 2015年第1期57-70,共14页
In the present paper we derived, with direct method, the exact expressions for the sampling probability density function of the Gini concentration ratio for samples from a uniform population of size n = 6, 7, 8, 9 and... In the present paper we derived, with direct method, the exact expressions for the sampling probability density function of the Gini concentration ratio for samples from a uniform population of size n = 6, 7, 8, 9 and 10. Moreover, we found some regularities of such distributions valid for any sample size. 展开更多
关键词 GINI Concentration Ratio uniform DISTRIBUTION order STATISTICS PROBABILITY Density Function
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A New Eighth Order Implicit Block Algorithms for the Direct Solution of Second Order Ordinary Differential Equations
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作者 Ademola M. Badmus 《American Journal of Computational Mathematics》 2014年第4期376-386,共11页
This paper focuses on derivation of a uniform order 8 implicit block method for the direct solution of general second order differential equations through continuous coefficients of Linear Multi-step Method (LMM). The... This paper focuses on derivation of a uniform order 8 implicit block method for the direct solution of general second order differential equations through continuous coefficients of Linear Multi-step Method (LMM). The continuous formulation and its first derivatives were evaluated at some selected grid and off grid points to obtain our proposed method. The superiority of the method over the existing methods is established numerically. 展开更多
关键词 uniform order SECOND order Initial Value Problem IMPLICIT Block Algorithms ZERO Stable
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On the Fifth-Order Stokes Solution for Steady Water Waves 被引量:1
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作者 ZHAO Hong-jun SONG Zhi-yao +3 位作者 LI Ling KONG Jun WANG Le-qiang YANG Jie 《China Ocean Engineering》 SCIE EI CSCD 2016年第5期794-810,共17页
This paper presents a universal fifth-order Stokes solution for steady water waves on the basis of potential theory. It uses a global perturbation parameter, considers a depth uniform current, and thus admits the flex... This paper presents a universal fifth-order Stokes solution for steady water waves on the basis of potential theory. It uses a global perturbation parameter, considers a depth uniform current, and thus admits the flexibilities on the definition of the perturbation parameter and on the determination of the wave celerity. The universal solution can be extended to that of Chappelear (1961), confirming the correctness for the universal theory. Furthermore, a particular fifth-order solution is obtained where the wave steepness is used as the perturbation parameter. The applicable range of this solution in shallow depth is analyzed. Comparisons with the Fourier approximated results and with the experimental measurements show that the solution is fairly suited to waves with the Ursell number not exceeding 46.7. 展开更多
关键词 steady water waves universal Stokes solution fifth-order global perturbation parameter uniform current wave steepness
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On the best convergence order of a new class of triangular summation operators
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作者 孟佳娜 赵连霞 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期399-401,共3页
In this paper, a new class of triangular summation operators based on the equidistant nodes was constructed. It is proved that this class of operators converges uniformly to arbitrary continuous fimctions with the per... In this paper, a new class of triangular summation operators based on the equidistant nodes was constructed. It is proved that this class of operators converges uniformly to arbitrary continuous fimctions with the period 2π on the whole axis, Fttrthermore, the best approximation order and the highest convergence order are obtained. In contrast to certain operators constructed by Bernstein and Kis in the previous works, the convergence properties of the new operator constructed in this paper are superior. 展开更多
关键词 triangular summation operator uniform convergence the best approxdmation order the highest convergence order
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Dynamic Analysis of Fractional-Order Fuzzy BAM Neural Networks with Delays in the Leakage Terms
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作者 Pan Wang Jianwei Shen 《Applied Mathematics》 2017年第12期1808-1819,共12页
In this paper, based on the theory of fractional-order calculus, we obtain some sufficient conditions for the uniform stability of fractional-order fuzzy BAM neural networks with delays in the leakage terms. Moreover,... In this paper, based on the theory of fractional-order calculus, we obtain some sufficient conditions for the uniform stability of fractional-order fuzzy BAM neural networks with delays in the leakage terms. Moreover, the existence, uniqueness and stability of its equilibrium point are also proved. A numerical example is presented to demonstrate the validity and feasibility of the proposed results. 展开更多
关键词 FRACTIONAL-order Fuzzy BAM Neural Networks uniform Stability Delay LEAKAGE TERMS
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Existence and Stability Analysis of Fractional Order BAM Neural Networks with a Time Delay
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作者 Yuping Cao Chuanzhi Bai 《Applied Mathematics》 2015年第12期2057-2068,共12页
Based on the theory of fractional calculus, the contraction mapping principle, Krasnoselskii fixed point theorem and the inequality technique, a class of Caputo fractional-order BAM neural networks with delays in the ... Based on the theory of fractional calculus, the contraction mapping principle, Krasnoselskii fixed point theorem and the inequality technique, a class of Caputo fractional-order BAM neural networks with delays in the leakage terms is investigated in this paper. Some new sufficient conditions are established to guarantee the existence and uniqueness of the nontrivial solution. Moreover, uniform stability of such networks is proposed in fixed time intervals. Finally, an illustrative example is also given to demonstrate the effectiveness of the obtained results. 展开更多
关键词 BAM Neural Networks Caputo FRACTIONAL-order EXISTENCE Fixed Point THEOREMS uniform Stability
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分数阶时滞神经网络的一致稳定性
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作者 宋超 《南京工程学院学报(自然科学版)》 2023年第1期84-88,共5页
研究一类带有时滞的Caputo型分数阶神经网络的解的动力学行为.基于等价范数定理、不等式技巧以及压缩映像定理,经过计算证明得到了分数阶神经网络的解存在唯一性和一致稳定性的结论;通过一个分数阶时滞神经网络模型实例验证了所得结论... 研究一类带有时滞的Caputo型分数阶神经网络的解的动力学行为.基于等价范数定理、不等式技巧以及压缩映像定理,经过计算证明得到了分数阶神经网络的解存在唯一性和一致稳定性的结论;通过一个分数阶时滞神经网络模型实例验证了所得结论的有效性. 展开更多
关键词 神经网络 分数阶 时滞 一致稳定
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系统观念指导下的人工智能刑事立法研究 被引量:7
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作者 马路瑶 《青少年犯罪问题》 2023年第2期20-32,共13页
系统观念指导人工智能刑事立法具有理论优势,能够避免“技术决定论”在主导立法中走向极端,避免立法决策顾此失彼。在系统观念的指导下,人工智能刑事立法应坚持“三个统筹”:一是统筹安全和发展,应坚持总体国家安全观,以保障人工智能的... 系统观念指导人工智能刑事立法具有理论优势,能够避免“技术决定论”在主导立法中走向极端,避免立法决策顾此失彼。在系统观念的指导下,人工智能刑事立法应坚持“三个统筹”:一是统筹安全和发展,应坚持总体国家安全观,以保障人工智能的发展真正造福人类社会;二是统筹多方参与主体,在人工智能不具备法律主体资格的现实基础下,应合理确定各方参与主体的刑事责任,确定适格被害人;三是统筹国内法治和涉外法治,应在国内立法中遵循法秩序统一性,立足于构建人类命运共同体贯通国内立法与涉外立法。 展开更多
关键词 人工智能 系统观念 总体国家安全观 法秩序统一性 涉外法治
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