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91.
本文针对工件间具有链状优先约束和relocation资源约束的极小化加权总完工时间调度优化问题展开研究.针对这一NP难问题,利用relocation约束的性质和贪婪算法的思想,设计了一个多项式近似算法,并证明了当链不可中断,每个链具有相同工件数和工件间具有相同加工时间时,2为该算法的紧界. 相似文献
92.
As a first step towards the numerical analysis of the stochastic primitive equations of the atmosphere and the oceans,the time discretization of these equations by an implicit Euler scheme is studied.From the deterministic point of view,the 3D primitive equations are studied in their full form on a general domain and with physically realistic boundary conditions.From the probabilistic viewpoint,this paper deals with a wide class of nonlinear,state dependent,white noise forcings which may be interpreted in either the It6 or the Stratonovich sense.The proof of convergence of the Euler scheme,which is carried out within an abstract framework,covers the equations for the oceans,the atmosphere,the coupled oceanic-atmospheric system as well as other related geophysical equations.The authors obtain the existence of solutions which are weak in both the PDE and probabilistic sense,a result which is new by itself to the best of our knowledge. 相似文献
93.
In this paper, we first prove that the local time associated with symmetric -stable processes is of bounded -variation for any partly based on Barlow’s estimation of the modulus of the local time of such processes. The fact that the local time is of bounded -variation for any enables us to define the integral of the local time as a Young integral for less smooth functions being of bounded -variation with . When , Young’s integration theory is no longer applicable. However, rough path theory is useful in this case. The main purpose of this paper is to establish a rough path theory for the integration with respect to the local times of symmetric -stable processes for . 相似文献
94.
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96.
刘会茹 《数学的实践与认识》2017,(12):263-268
讨论了企业投资系统的Lyapunov稳定性,得到了企业投资系统渐进稳定的充分条件和稳定的必要条件,并给出了企业投资系统的临界积累率的表达式,这个问题的研究对于促进我国经济高速、稳定持续增长具有重要的理论意义和现实指导价值. 相似文献
97.
研究了二元叠加码Mq(t,k,d)也是一个二元等重码,给出了它成为最佳等重码的条件,研究了它的检错性. 相似文献
98.
刘臻 《数学年刊A辑(中文版)》2017,38(2):201-214
研究了完全耦合正倒向随机控制系统的最优控制问题.得到了粘性解框架下的,控制变量同时出现在正倒向随机系统的漂移项和扩散项中的最优控制问题的验证定理.还讨论了验证定理在构造随机最优反馈控制中的应用. 相似文献
99.
A Markov observation model with dividend is defined and the interpretation of the practical significance is given. We try to use an irreducible and homogeneous discrete-time Markov chain to modulate the inter-observation times and embed a dividend strategy. In the Markov observation model with dividend, a system of liner equations for the expected discounted value of dividends until ruin time is derived. Moreover, an explicit expression is obtained and proved. Finally, some interesting properties are illustrated by numerical analysis and by comparing with the complete compound binomial model with dividend. 相似文献
100.
A cured model is a useful approach for analysing failure
time data in which some subjects could eventually experience and others never
experience the event of interest. All subjects in the test belong to one of the
two groups: the susceptible group and the non-susceptible group. There has been
considerable progress in the development of semi-parametric models for regression
analysis of time-to-event data. However, most of the current work focuses on
right-censored data, especially when the population contains a non-ignorable
cured subgroup. In this paper, we propose a semi-parametric cure model for current
status data. In general, treatments are developed to both increase the patients'
chances of being cured and prolong the survival time among non-cured patients. A
logistic regression model is proposed for whether the subject is in the susceptible
group. An accelerated failure time regression model is proposed for the event
time when the subject is in the non-susceptible group. An EM algorithm is used
to maximize the log-likelihood of the observed data. Simulation results show that
the proposed method can get efficient estimations. 相似文献