期刊文献+
共找到220篇文章
< 1 2 11 >
每页显示 20 50 100
Comparison principle and stability criteria for stochastic differential delay equations with Markovian switching 被引量:12
1
作者 罗交晚 邹捷中 侯振挺 《Science China Mathematics》 SCIE 2003年第1期129-138,共10页
In the present paper we first obtain the comparison principle for the nonlinear stochastic differentialdelay equations with Markovian switching. Later, using this comparison principle, we obtain some stabilitycriteria... In the present paper we first obtain the comparison principle for the nonlinear stochastic differentialdelay equations with Markovian switching. Later, using this comparison principle, we obtain some stabilitycriteria, including stability in probability, asymptotic stability in probability, stability in the pth mean, asymptoticstability in the pth mean and the pth moment exponential stability of such equations. Finally, an example isgiven to illustrate the effectiveness of our results. 展开更多
关键词 comparison principle Brownian motion stochastic differential delay equations generalized Ito’s formula Markov chain
原文传递
单面约束系统动力学研究进展 被引量:9
2
作者 张毅 《力学与实践》 CSCD 北大核心 2000年第4期8-11,48,共5页
综述了单面约束系统动力学研究的历史与现状.并提出未来研究的建议.
关键词 分析力学 变分原理 动力学 单面约束系统
下载PDF
荷载横向变位下箱梁剪滞效应分析 被引量:9
3
作者 王继兵 周德源 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2011年第2期159-164,共6页
为了研究荷载横向变位下对箱梁剪滞效应的影响,对箱梁底板、顶板及悬臂板分设不同的纵向位移差函数,采用二次抛物线作为箱梁翼缘板的纵向位移沿梁宽分布函数,基于能量变分原理,建立了考虑剪滞效应的箱型梁控制微分方程;分析了荷载在箱... 为了研究荷载横向变位下对箱梁剪滞效应的影响,对箱梁底板、顶板及悬臂板分设不同的纵向位移差函数,采用二次抛物线作为箱梁翼缘板的纵向位移沿梁宽分布函数,基于能量变分原理,建立了考虑剪滞效应的箱型梁控制微分方程;分析了荷载在箱梁顶板横向变位下底板、顶板及悬臂板应力的变化规律,根据对简支箱梁在均布荷载作用下跨中剪力滞系数的计算结果,随着作用在顶板的荷载从肋板向顶板中心移动,顶板经历一个产生正剪力滞效应和无剪力滞效应,最后到产生负剪力滞效应的变化过程,而底板及悬臂板在荷载移动过程中始终保持正剪力滞效应.计算结果和有限元数值模拟结果吻合较好,验证了理论的可靠性,与以往的研究相比更能正确地反映结构剪力滞效应的变化规律. 展开更多
关键词 箱型梁 剪力滞 变分原理 有限元 微分方程
下载PDF
实现GIS故障精准辨识切除及自动恢复供电的母线保护新原理 被引量:10
4
作者 李乃永 张美玲 +2 位作者 王昕 吴金玉 刘承禄 《电网技术》 EI CSCD 北大核心 2015年第10期2965-2971,共7页
为实现GIS故障精准辨识切除及自动恢复供电,提出一种母线保护新原理。基于母线大范围、小范围及各支路间隔复式比率差动原理,精准辨识隔离GIS设备故障点,线路侧CT与断路器之间故障时,仅跳开故障间隔断路器实现故障隔离;断路器与母线侧C... 为实现GIS故障精准辨识切除及自动恢复供电,提出一种母线保护新原理。基于母线大范围、小范围及各支路间隔复式比率差动原理,精准辨识隔离GIS设备故障点,线路侧CT与断路器之间故障时,仅跳开故障间隔断路器实现故障隔离;断路器与母线侧CT间故障时,自动/手动拉开单间隔刀闸隔离故障,母线上运行的所有非故障健全元件保持继续运行;母联断路器与I(II)母线侧CT之间故障时,跳开母联断路器及I(II)母线,II(I)母线正常运行;发生无法隔离的母线故障时,由母线保护正确动作跳开所有联接元件。该原理有效解决了GIS设备单间隔、母联死区故障时母线保护无选择性动作从而扩大停电范围的难题,配合母线自动重合闸,可实现最小范围快速切除故障和自动重合以快速恢复供电。理论分析和实际应用案例验证了新原理的有效性和可行性。 展开更多
关键词 多重区域 差动原理 母线保护 GIS故障精准隔离及自动恢复
下载PDF
一阶线性模糊微分方程的解 被引量:9
5
作者 王磊 郭嗣琮 《模糊系统与数学》 CSCD 北大核心 2011年第3期113-118,共6页
利用文[8]中的扩展原理求解了一阶线性模糊微分方程,给出了解可表示的条件,讨论了同其他求解方法之间的关系,最后给出了具体算例。
关键词 扩展原理 模糊初值 刻画方程 微分闭包 推广Hukuhara导数
原文传递
Optimal variational principle for backward stochastic control systems associated with Lévy processes 被引量:8
6
作者 TANG MaoNing 1 & ZHANG Qi 2,1 Department of Mathematical Sciences,Huzhou University,Huzhou 313000,China 2 School of Mathematical Sciences,Fudan University,Shanghai 200433,China 《Science China Mathematics》 SCIE 2012年第4期745-761,共17页
The paper is concerned with optimal control of backward stochastic differentiM equation (BSDE) driven by Teugel's martingales and an independent multi-dimensional Brownian motion, where Teugel's martingales are a ... The paper is concerned with optimal control of backward stochastic differentiM equation (BSDE) driven by Teugel's martingales and an independent multi-dimensional Brownian motion, where Teugel's martingales are a family of pairwise strongly orthonormal martingales associated with L6vy processes (see e.g., Nualart and Schoutens' paper in 2000). We derive the necessary and sufficient conditions for the existence of the optimal control by means of convex variation methods and duality techniques. As an application, the optimal control problem of linear backward stochastic differential equation with a quadratic cost criteria (or backward linear-quadratic problem, or BLQ problem for short) is discussed and characterized by a stochastic Hamilton system. 展开更多
关键词 stochastic control stochastic maximum principle Ldvy processes Teugel's martingales backwardstochastic differential equations
原文传递
高空作业平台臂架变幅振动特性研究 被引量:7
7
作者 王豪 纪爱敏 +1 位作者 张磊 邓铭 《振动与冲击》 EI CSCD 北大核心 2020年第8期40-46,共7页
在现有高空作业平台直臂的变幅振动特性研究中,将臂架简化为一变截面悬臂梁,亦即视变幅油缸、臂架和转台相连的三角部位为刚性区域;这样,势必带来其分析结果的误差。为此,考虑臂架的实际连接和支承情况,将伸缩臂架等效为根部铰支、中间... 在现有高空作业平台直臂的变幅振动特性研究中,将臂架简化为一变截面悬臂梁,亦即视变幅油缸、臂架和转台相连的三角部位为刚性区域;这样,势必带来其分析结果的误差。为此,考虑臂架的实际连接和支承情况,将伸缩臂架等效为根部铰支、中间弹性支承且带有集中参数的变截面梁;基于哈密顿原理建立了变幅过程中臂架振动的微分方程,求解得到臂架振动的固有频率和振型,在此基础上结合特解和振型之间的正交性得到希尔伯特空间内臂架振动的状态空间方程,在Matlab/Simulink环境下进行动态仿真,可以得到随着仰角变化,臂架头部的振动响应。结果表明,所得臂架头部的振幅超过常规研究中29%以上,该研究可为高空作业平台振动控制提供更为精确的理论参考。 展开更多
关键词 哈密顿原理 微分方程 状态空间方程 振动响应
下载PDF
中西医结合神经病学Midnights原则临床思维探索 被引量:7
8
作者 施扬 陈准立 +5 位作者 王欣 侍鑫杰 徐川 陆玲丹 金燕 陆征宇 《中国中医药现代远程教育》 2018年第6期90-92,共3页
中西医结合神经病学是运用传统中医理论结合现代神经病学,利用现代科技手段,研究神经系统疾病的发生、发展、变化规律和诊疗技术,是一门跨专业、跨学科的临床学科。该学科专业性强,内容复杂抽象难懂,临床病种繁多、病情多变,临床诊断思... 中西医结合神经病学是运用传统中医理论结合现代神经病学,利用现代科技手段,研究神经系统疾病的发生、发展、变化规律和诊疗技术,是一门跨专业、跨学科的临床学科。该学科专业性强,内容复杂抽象难懂,临床病种繁多、病情多变,临床诊断思维方式特别,必须有定位诊断和定性诊断,往往是医学生学习的难点。"Midnights"原则临床思维可以针对临床实际病例轻松进行病因大类的排除鉴别诊断,代表着一种开放的、非固定、非封闭式的教学模式,让学生知识体系更完整,极大地激发学生对中西医结合神经内科学的兴趣,提高临床教学效果。 展开更多
关键词 中西医结合神经病学 临床教学 临床思维 Midnights原则 鉴别诊断
下载PDF
Maximum Principle for Stochastic Control System with Elephant Memory and Jump Diffusion
9
作者 FENG Siqi GAO Lei +1 位作者 WANG Guangchen XIAO Hua 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2024年第4期1392-1412,共21页
Motivated by a duopoly game problem,the authors study an optimal control problem where the system is driven by Brownian motion and Poisson point process and has elephant memory for the control variable and the state v... Motivated by a duopoly game problem,the authors study an optimal control problem where the system is driven by Brownian motion and Poisson point process and has elephant memory for the control variable and the state variable.Firstly,the authors establish the unique solvability of an anticipated backward stochastic differential equation,derive a stochastic maximum principle,and prove a verification theorem for the aforementioned optimal control problem.Furthermore,the authors generalize these results to nonzero-sum stochastic differential game problems.Finally,the authors apply the theoretical results to the duopoly game problem and obtain the corresponding Nash equilibrium solution. 展开更多
关键词 Anticipated backward stochastic differential equation elephant memory Fréchet derivative maximum principle stochastic delayed differential equation
原文传递
一阶线性模糊微分方程的模糊结构元解法 被引量:6
10
作者 王磊 郭嗣琮 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第10期1576-1579,共4页
文章利用模糊结构元原理,研究了一阶线性模糊微分方程的模糊初值问题,证明了方程解的存在性和唯一性条件,给出了解的模糊结构元的解析表达形式,讨论了同其他求解方法之间的关系。结果表明,模糊结构元方法是研究模糊微分方程的一个有效... 文章利用模糊结构元原理,研究了一阶线性模糊微分方程的模糊初值问题,证明了方程解的存在性和唯一性条件,给出了解的模糊结构元的解析表达形式,讨论了同其他求解方法之间的关系。结果表明,模糊结构元方法是研究模糊微分方程的一个有效工具。 展开更多
关键词 模糊结构元 扩展原理 微分闭包 推广Hukuhara导数
下载PDF
对变分原理中时间微商类型的分析 被引量:4
11
作者 丁光涛 《安徽师范大学学报(自然科学版)》 CAS 北大核心 2011年第5期429-431,共3页
将变分原理中时间微商划分三种类型,回答了梅凤翔在对称性研究中提出的问题;解释了分析力学中两种算子对易关系之间的区别.
关键词 变分原理 时间微商 对称性 算子对易关系
下载PDF
双轮毂驱动电动汽车电子差速控制的研究 被引量:4
12
作者 周翠玉 路春光 李成群 《机械工程与自动化》 2013年第3期46-47,50,共3页
针对轮毂电机驱动的电动汽车的转向问题,利用机械差速器的原理,提出了一种"差速不差力"的"自适应"电子差速器。通过对两侧驱动电机电磁转矩的控制,进而达到对驱动电机差速的控制。设计了电子差速的控制过程,并进行... 针对轮毂电机驱动的电动汽车的转向问题,利用机械差速器的原理,提出了一种"差速不差力"的"自适应"电子差速器。通过对两侧驱动电机电磁转矩的控制,进而达到对驱动电机差速的控制。设计了电子差速的控制过程,并进行了MATLAB仿真,证明了此设计的可行性。 展开更多
关键词 轮毂电机 电动汽车 自适应 电子差速
下载PDF
A BSDE Approach to Stochastic Differential Games Involving Impulse Controls and HJBI Equation 被引量:1
13
作者 ZHANG Liangquan 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2022年第3期766-801,共36页
This paper focuses on zero-sum stochastic differential games in the framework of forwardbackward stochastic differential equations on a finite time horizon with both players adopting impulse controls.By means of BSDE ... This paper focuses on zero-sum stochastic differential games in the framework of forwardbackward stochastic differential equations on a finite time horizon with both players adopting impulse controls.By means of BSDE methods,in particular that of the notion from Peng’s stochastic backward semigroups,the authors prove a dynamic programming principle for both the upper and the lower value functions of the game.The upper and the lower value functions are then shown to be the unique viscosity solutions of the Hamilton-Jacobi-Bellman-Isaacs equations with a double-obstacle.As a consequence,the uniqueness implies that the upper and lower value functions coincide and the game admits a value. 展开更多
关键词 Dynamic programming principle(DPP) forward-backward stochastic differential equations(FBSDEs) Hamilton-Jacobi-Bellman-Isaacs(HJBI) impulse control stochastic differential games value function viscosity solution
原文传递
HBF-S140/10加压过滤机在铁精矿过滤的应用实践 被引量:2
14
作者 苏琴 岳中魁 邢守正 《矿业工程》 CAS 2017年第4期36-37,共2页
以某选矿厂采用HBF-S140/10加压过滤机处理铁精矿为例,介绍加压过滤机的结构、工作原理及操作参数。
关键词 加压过滤机 铁精矿 工作原理 压差
下载PDF
AN AVERAGING PRINCIPLE FOR STOCHASTIC DIFFERENTIAL DELAY EQUATIONS DRIVEN BY TIME-CHANGED LéVY NOISE 被引量:1
15
作者 Guangjun SHEN Wentao XU Jiang-Lun WU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期540-550,共11页
In this paper,we aim to derive an averaging principle for stochastic differential equations driven by time-changed Lévy noise with variable delays.Under certain assumptions,we show that the solutions of stochasti... In this paper,we aim to derive an averaging principle for stochastic differential equations driven by time-changed Lévy noise with variable delays.Under certain assumptions,we show that the solutions of stochastic differential equations with time-changed Lévy noise can be approximated by solutions of the associated averaged stochastic differential equations in mean square convergence and in convergence in probability,respectively.The convergence order is also estimated in terms of noise intensity.Finally,an example with numerical simulation is given to illustrate the theoretical result. 展开更多
关键词 Averaging principle stochastic differential equation time-changed Levy noise variable delays
下载PDF
Large deviation principle for diffusion processes under a sublinear expectation 被引量:2
16
作者 CHEN ZengJing 1,2 & XIONG Jie 3,4,1 School of Mathematics,Shandong University,Jinan 250100,China 2 Department of Financial Engineering,Ajou University,Suwon 443749,Korea +1 位作者 3 Department of Mathematics,University of Macao,PO Box 3001,Macao,China 4 Department of Mathematics,University of Tennessee,Knoxville,TN 37996-1300,USA 《Science China Mathematics》 SCIE 2012年第11期2205-2216,共12页
We represent the exponential moment of the Brownian functionals under a nonlinear expectation according to the solution to a backward stochastic differential equation.As an application,we establish a large deviation p... We represent the exponential moment of the Brownian functionals under a nonlinear expectation according to the solution to a backward stochastic differential equation.As an application,we establish a large deviation principle of the Freidlin and Wentzell type under the corresponding nonlinear probability for diffusion processes with a small diffusion coefficient. 展开更多
关键词 large deviation principle backward stochastic differential equation G-EXPECTATION AMBIGUITY
原文传递
LAGRANGIAN MECHANICS ON KAHLER MANIFOLDS
17
作者 张荣业 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第10期1363-1374,共12页
Lagrangian mechanics on Kahler manifolds were discussed, and the complex mathematical aspects of Lagrangian operator, Lagrange's equation, the action functional, Hamilton' s principle, Hamilton' s equation and so o... Lagrangian mechanics on Kahler manifolds were discussed, and the complex mathematical aspects of Lagrangian operator, Lagrange's equation, the action functional, Hamilton' s principle, Hamilton' s equation and so on were given. 展开更多
关键词 Kahler manifold absolute differential Lagrangian operator Hamilton' s principle
下载PDF
Temporal Prediction of Aircraft Loss-of-Control: A Dynamic Optimization Approach
18
作者 Chaitanya Poolla Abraham K. Ishihara 《Intelligent Control and Automation》 2015年第4期241-248,共8页
Loss of Control (LOC) is the primary factor responsible for the majority of fatal air accidents during past decade. LOC is characterized by the pilot’s inability to control the aircraft and is typically associated wi... Loss of Control (LOC) is the primary factor responsible for the majority of fatal air accidents during past decade. LOC is characterized by the pilot’s inability to control the aircraft and is typically associated with unpredictable behavior, potentially leading to loss of the aircraft and life. In this work, the minimum time dynamic optimization problem to LOC is treated using Pontryagin’s Maximum Principle (PMP). The resulting two point boundary value problem is solved using stochastic shooting point methods via a differential evolution scheme (DE). The minimum time until LOC metric is computed for corresponding spatial control limits. Simulations are performed using a linearized longitudinal aircraft model to illustrate the concept. 展开更多
关键词 Pilot ASSISTANCE Loss of CONTROL Aircrafts Dynamic Optimization TEMPORAL PREDICTION Pontryagin Maximum principle differential Evolution Stochastic SHOOTING Point Methods
下载PDF
直流双系统供电模式可靠性分析及建设维护建议 被引量:1
19
作者 张少文 《通信电源技术》 2019年第8期108-109,112,共3页
为克服单系统供电的瓶颈问题,提升通信网络供电安全可靠性,重要直流通信设备采取双系统双路由供电(主备供电模式)。分析了直流双系统双路由供电模式的工作原理及其应用场景,并对目前要求双系统双路由供电模式的典型通信设备进行了测试验... 为克服单系统供电的瓶颈问题,提升通信网络供电安全可靠性,重要直流通信设备采取双系统双路由供电(主备供电模式)。分析了直流双系统双路由供电模式的工作原理及其应用场景,并对目前要求双系统双路由供电模式的典型通信设备进行了测试验证,得出了双系统双路由供电模式运行安全可靠,并提出了双系统双路由供电模式维护建设中的注意事项。 展开更多
关键词 双系统供电 工作原理 压差 测试验证
下载PDF
Controlled Mean-Field Backward Stochastic Differential Equations with Jumps Involving the Value Function 被引量:1
20
作者 LI Juan MIN Hui 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第5期1238-1268,共31页
This paper discusses mean-field backward stochastic differentiM equations (mean-field BS- DEs) with jumps and a new type of controlled mean-field BSDEs with jumps, namely mean-field BSDEs with jumps strongly coupled... This paper discusses mean-field backward stochastic differentiM equations (mean-field BS- DEs) with jumps and a new type of controlled mean-field BSDEs with jumps, namely mean-field BSDEs with jumps strongly coupled with the value function of the associated control problem. The authors first prove the existence and the uniqueness as well as a comparison theorem for the above two types of BSDEs. For this the authors use an approximation method. Then, with the help of the notion of stochastic backward semigroups introduced by Peng in 1997, the authors get the dynamic programming principle (DPP) for the value functions. Furthermore, the authors prove that the value function is a viscosity solution of the associated nonlocal Hamilton-Jacobi-Bellman (HJB) integro-partial differential equation, which is unique in an adequate space of continuous functions introduced by Barles, et al. in 1997. 展开更多
关键词 Dynamic programming principle (DPP) Hamilton-Jacobi-Bellman (HJB) equation mean-field backward stochastic differential equation (mean-field BSDE) with jump Poisson random measure value function.
原文传递
上一页 1 2 11 下一页 到第
使用帮助 返回顶部