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1.
借助于与给定共振的非线性周期边值问题相关的非共振的线性边值问题来构造算子,利用范数形式的锥拉伸-压缩不动点定理,得到了非线性周期边值问题非负解的存在性定理.  相似文献   

2.
林娟 《数学杂志》2011,31(6):1103-1108
本文研究了一般周期Riemann边值问题关于跳跃曲线的稳定性.利用解析函数边值理论和不等式分析理论,获得了一般周期Riemann边值问题的解及其关于跳跃曲线的误差估计.  相似文献   

3.
本文首先证明源于DNA的非线性波动方程组的周期边值问题局部古典解的存在性和唯一性.其次通过周期边值问题序列证明这个方程组的Cauchy问题存在唯一的局部古典解.  相似文献   

4.
田颖辉 《大学数学》2017,33(3):14-19
基于格林函数理论,主要利用Lerray-Schauder抉择定理和上下解方法针对半正定条件下,奇异超线性二阶周期边值问题正解的存在性进行推理证明,获取了奇异超线性二阶周期边值问题的一个正解.  相似文献   

5.
该文研究了一类具有p-Laplacian算子的非线性Caputo分数阶微分方程反周期边值问题解的存在唯一性.首先,利用分数阶微分方程和反周期边值条件给出了该边值问题的Green函数,然后利用p-Laplacian算子的性质和Banach压缩映射原理得到该边值问题解的存在唯一性结论,最后给出两个例子验证结论的合理性.值得一提的是此文研究的微分方程的反周期边值条件是带有Caputo分数阶微分.  相似文献   

6.
本文研究了一类一阶脉冲时滞积分微分方程边值问题解的性质. 利用迭代分析方法, 得到了该类边值问题解的存在性、唯一性和平凡解一致稳定的充分条件, 推广了已有积分微分方程周期边值问题解的结论.  相似文献   

7.
本文研究了一类一阶脉冲时滞积分微分方程边值问题解的性质.利用迭代分析方法,得到了该类边值问题解的存在性、唯一性和平凡解一致稳定的充分条件,推广了已有积分微分方程周期边值问题解的结论.  相似文献   

8.
单准周期的Riemann边值问题   总被引:1,自引:0,他引:1  
戴济能  杜金元 《数学杂志》2006,26(5):579-584
本文研究了光滑封闭曲线情况下的加法与乘法单准周期Riemann边值问题,运用保角变换的方法,获得了单准周期函数的一些性质,并且对解在无穷远处作适当要求下给出了单准周期边值问题的解法.  相似文献   

9.
利用不动点指数理论研究奇异二阶周期边值问题.在有关其线性算子方程对应的第一特征值的条件下得到边值问题正解的存在性,推广和改进了最近文献的结果.  相似文献   

10.
考虑一类一阶常微分方程的周期边值问题,利用Schaefer不动点定理得到了边值问题解存在的一个充分条件,推广了相关文献中已有的结果.  相似文献   

11.
12.
An asymptotic analysis of the dynamic stress-strain state of a thin laminar packet of anisotropic layers is presented. The statement is nonclassical, since in layer materials the ratio of elastic moduli in the longitudinal and transverse directions can generate small parameters comparable to the relative half-thickness of the packet, as, for example, in high-strength unidirectional composites. Alternation of strong load-carrying layers and a relatively soft filler with a similar difference in the elastic moduli between the layers is also allowed. The averaged two-dimensional equations and the total stress tensor in the layers are determined. The results are classified with respect to the types of anisotropy and the indices of differences in the elastic moduli. It is shown that first-approximation models lead to kinematic relations similar to those of the theories of high-order shear strains. Institute of Problems of Mechanics, Russian Academy of Sciences, Moscow, Russia. Translated from Mekhanika Kompozitnykh Materialov, Vol. 35, No. 5, pp. 605–614, September–October, 1999.  相似文献   

13.
文[4]提出了网络优化中若干有待解决的组合问题,本文围绕其中之一“减小直径问题”进行了探讨.设P(n,t)表示长为n的路径增加t条边后所得图直径的最小值,C(n,t)表示长为n的圈增加t条边后所得回直径的最小值.本文取得如下进展:1)给出P(n,2),P(n,3)及C(n,2)的精确值,并得出P(n,4)的一更精细的上界及一种更好的加边方式.上述结果均满足小极大度原则.2)在有极大度限制的条件下,分别对t为偶数和奇数给出了P(n,t)的上界.  相似文献   

14.
In this paper, we deal with the effect of the shape of herd behavior on the interaction between predator and prey. The model analysis was studied in three parts. The first, The analysis of the system in the absence of spatial diffusion and the time delay, where the local stability of the equilibrium states, the existence of Hopf bifurcation have been investigated. For the second part, the spatiotemporal dynamics introduce by self diffusion was determined, where the existence of Hopf bifurcation, Turing driven instability, Turing-Hopf bifurcation point have been proved. Further, the order of Hopf bifurcation points and regions of the stability of the non trivial equilibrium state was given. In the last part of the paper, we studied the delay effect on the stability of the non trivial equilibrium, where we proved that the delay can lead to the instability of interior equilibrium state, and also the existence of Hopf bifurcation. A numerical simulation was carried out to insure the theoretical results.  相似文献   

15.
肝药酶诱导剂苯巴比妥能诱导细胞色素P-450的合成,而肝药酶抑制剂放线菌素D能抑制细胞色素P-450的合成,本实验应用示差光谱法对P-450含量加以测定.本文改进了传统的计算药后诱导组和抑制组P-450含量增加或减少的百分比来评价药物的方法,在M athem atica数学软件环境下,对数据进行方差分析和t检验,提高了数据处理精度和可信度.并对原方法表示怀疑.  相似文献   

16.
Properties of a model composite based on an ED-22 epoxy binder, cured with polyprophylene polyamine, and disperse LiF crystals as a filler were investigated by the methods of dilatometry and X-ray diffractometry. It was established that the density of cross-links of the epoxy binder in the interphase layer was lower than in a block specimen. Therefore, the thermal expansion of the composite on heating to 120°C, in terms of that of the binder, grew significantly with the degree of filling ϕ, and the water uptake also increased at the initial stage. The presence of absorbed water led to considerable changes in the structure and properties of the composite interphase: the binder became more cross-linked, its structural ordering decreased, the thermal expansion at heating diminished by a factor of 3. 7 (at ϕ = 50%), and the glass-transition temperature increased. As a result of long-term action of moisture, changes in the internal stresses had an extreme character.__________Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 4, pp. 535–544, July–August, 2005.  相似文献   

17.
The paper presents results of numerical and experimental investigations into the vibrations of thin-walled structures, considering such their features as the complexity of geometry, the laminated structure of walls, the anisotropy of materials, the presence of stiffeners, and the initial stresses. The object of the study is the sounding board of an acoustic guitar, the main structural material of which is a three-layer birch veneer. Based on the finite-element method, a corresponding calculation model is created, and the steady-state regimes of forced vibrations of the sounding board are investigated. A good correspondence between calculation results and experimental data is found to exist. __________ Translated from Mekhanika Kompozitnykh Materialov, Vol. 43, No. 3, pp. 399–410, May–June, 2007.  相似文献   

18.
低轨卫星通信网络的抗毁性是描述网络安全可靠的有效工具,在网络体系结构设计和路由策略等领域得到了广泛的应用。根据低轨卫星通信网络中卫星在轨道平面内移动,需要不断进行切换的特点,从建立抗毁性测度模型以及网络抗毁性优化两个角度来评估和提高网络抗毁性,提出一种基于韧性度的低轨卫星通信网络抗毁性度量方法。通过对移动模型以及切换模型的结构分析,对每种结构以一定概率出现的低轨卫星通信网络,应用韧性度函数,求得网络在某个时刻及某一段时间段内的抗毁性,并针对切换模型的不足之处进行优化,用赋权韧性度来体现优化的效果,得到了优化后的网络抗毁性。以铱星系统为应用实例进行仿真,结果表明:任意时刻网络的抗毁性跟拓扑结构的韧性度值有关,并且是一种线性关系,即随着韧性度的增加,其抗毁性也增加。通过对铱星通信系统切换模型的优化,网络的抗毁性与平均抗毁性都得到了提升,说明本文所构建模型的有效性和实用性。  相似文献   

19.
Operational probability theory appears as a smooth extension of classical probability theory that fulfills quantum physics needs. In this paper, we, first, explain the need to extend the concept of the intersection operation in the light of the concept of joint observables. Then, we tried to determine the basic features that characterize any possible definition of the intersection operation. Furthermore, we tried to know if there is a relation between the definitions of the intersection operation of both fuzzy and operational probability theories. These relations are used, first, to find a suitable suggestion to define the intersection operation. Second, they are used, besides the studies made on Bell inequalities in fuzzy probability theory, to find the conditions that should be satisfied by the intersection operation to ensure the possibility of the violation of Bell inequalities in operational probability theory.  相似文献   

20.
柳键  江玮璠 《运筹与管理》2018,27(12):100-107
存货质押是中小企业短期融资的有效手段,而企业对需求的过度自信会影响融资企业和银行的决策,从而影响到企业和银行的预期收益。针对过度自信环境下的存货质押决策问题,建立过度自信零售商和银行的存货质押博弈决策模型,采用Stackelberg博弈分析期望需求和需求波动性两方面过度自信对零售商销售努力、订货量和银行质押率的影响。研究表明:过度自信零售商融资更为激进,过度自信程度越高,对资金需求越大,投入销售努力越高,采购量越大,预期利润与实际利润之间的偏差越大;在低利润市场环境下,质押率随着过度自信的增加而降低,在高利润市场环境下,质押率会随着预测精度过度自信的增加而增加,随着期望需求过度自信的增加而下降。  相似文献   

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