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排序方式: 共有642条查询结果,搜索用时 15 毫秒
141.
罗韫逊 《江汉大学学报(人文科学版)》1996,(6)
本文将常系数线性微分方程的算子解法推广到变系数线性微分方程中,用新的方法──算子解法求解某些变系数的线性微分方程,给出了常系数线性方程特解公式. 相似文献
142.
刘岚喆 《长沙理工大学学报(社会科学版)》1988,(3)
共鸣定理是泛函分析中重要的基础定理之一,其形式也有多种变化。在[1]—[5]中讨论了一类共鸣定理,即所谓凸泛函族的共鸣定理。由于凸分析的广泛运用性,凸性的概念有必要进一步推广。本文首先给出p-凸性的概念,p-凸集和p-凸泛函具有完全类似于凸集和凸泛函的性质,然后导出了在拓扑向量空间及赋范空间中p-凸泛函族的几个共鸣定理,推广了文[1]—[5]中的相应结果。 相似文献
143.
本文利用Pegg—Barnett位相算符形式引入了有限维Hilbert空间的位相算符和位相态基,详细讨论了二态系统的位相算符表示及性质。 相似文献
144.
陈华富 《电子科技大学学报(社会科学版)》1997,(4)
利用梯度投影法与罚函数技巧,将带等式和不等式约束优化问题化成一个无约束问题,提出了求解不等式、等式约束优化问题的摄动梯度投影算法。考虑到计算的误差因素,在搜索方向上进行摄动,得到一个方向不精确的梯度投影法。参数δk取不同的数还可以得到一类梯度投影法。从而保证了在实际应用中更容易实现,在较弱的条件下,证明了该算法的全局收敛性。 相似文献
145.
Some notes on Church's thesis and the theory of games 总被引:2,自引:0,他引:2
Luca Anderlini 《Theory and Decision》1990,29(1):19-52
This paper considers games in normal form played by Turing Machines. The machines are fed as input all the relevent information and then are required to play the game. Some impossibility results are derived for this set-up. In particular, it is shown that no Turing Machine exists which will always play the correct strategy given its opponent's choice. Such a result also generalizes to the case in which attention is restricted to economically optimizing machines only. The paper also develops a model of knowledge. This allows the main results of the paper to be interpreted as stemming out of the impossibility of always deciding whether a player is rational or not in some appropriate sense. 相似文献
146.
Users of multistate life tables and projections have recognized that the Markovian assumptions underlying such models are unduly restrictive and should be relaxed whenever data permit. Efforts to include the influences of previous occupancies have included the incorporation of place‐of‐birth dependence. This paper addresses the stable growth properties of such generalized multistate models. It shows how place‐of‐birth‐specific stable growth measures can be calculated without projection simply by solving the characteristic equation. An example using Canadian data illustrates the argument. 相似文献
147.
Binomial thinning operator has a major role in modeling one-dimensional integer-valued autoregressive time series models. The purpose of this article is to extend the use of such operator to define a new stationary first-order spatial non negative, integer-valued autoregressive SINAR(1, 1) model. We study some properties of this model like the mean, variance and autocorrelation function. Yule-Walker estimator of the model parameters is also obtained. Some numerical results of the model are presented and, moreover, this model is applied to a real data set. 相似文献
148.
《Journal of Organisational Transformation & Social Change》2013,10(2):215-235
AbstractThe telecommunications business is undergoing a critical revolution, driven by innovative technologies, globalization and deregulation. Cellular networks and telecommunications bring radical changes to the way telecom businesses are conducted. Globalization, on the other hand, is tearing down legacy barriers and forcing monopolistic national carriers to compete internationally. Moreover, the noticeable progress of many countries towards deregulation coupled with liberalization is significantly increasing telecom market power and allowing severe competition. The implications of this transition have changed the business rules of the telecom industry. In addition, entrants into the cellular industry have had severe difficulties due to inexistent or weak business models (BMs). Designing a BM for a mobile network operator (MNO) is complex and requires multiple actors to balance different and often conflicting design requirements. Hence, there is a need to enhance operators' ability in determining what constitutes the most viable BM to meet their strategic objectives within this turbulent environment. In this article, the authors identify the main mobile BM dimensions along with their interdependencies and further analysis provides MNOs with insights to improve their BMs in this new 'boundary-less' landscape. 相似文献
149.
文章在Hilbert 空间中引入了一类新的涉及(A,η)单调映射的非线性集值隐似变分包含问题,基于与(A,η)单调性相关的广义预解算子技巧,用一种迭代算法研究了解的近似可解性,所得结果改进了许多近期结果. 相似文献
150.
本文研究了同伦分析方法中由基函数选择有效的辅助线性算子的方法,并将其应用到同伦分析方法中,求解了一个非线性偏微分方程边值问题,并且获得了收敛的级数解.结果表明此方法是有效的,也有利于同伦分析方法的进一步研究. 相似文献