带有Poisson跳的随机资产积累系统的最优逼近控制的必要条件

讨论了一类带有Poisson跳的随机资产积累系统的最优逼近控制问题,应用Ekeland变分原理,Itos公式及一些不等式,给出了随机资产积累系统最优逼近控制的必要条件.

提取图像边缘过程中抑制噪声的随机启发搜索算法

常用的边缘提取方法对噪声的抑制能力不强 ,导致了大量不连续边缘的产生。文中提出了一个随机启发式搜索算法 ,它能够有效地抑制噪声 ,从而连接到连续的边缘。同时 ,介绍了随机启发式搜索算法 ;讨论了起始点的选择准则和扩展点的选择方法 ;最后介绍了终止点选择的方法。一个起始点、一个终止点和许多扩展点就形成了一个候选边缘。通过候选边缘的随机积累进行自增强 ,达到抑制噪声、提取清晰边缘的目的。文中使用加入高斯噪声的“Lena”图像作为实验图像 ,实验结果初步证明了该算法能够提取到连续。

受随机扰动的两种资产积累模型的最优逼近控制

将随机扰动和资产积累过程中资产之间的相互影响考虑到模型中,讨论了一类带有Fractional Brown运动和Mark-ov调制的2种随机资产积累系统的最优逼近控制问题。采用最优控制的经典方法——最大值原理来对问题进行求解。利用Ito′s公式及一些基本不等式等证明了在利普希茨条件下,资产积累模型和其相对应的伴随方程的解都是有界的,并且给出了2种随机资产积累系统的最优逼近控制存在的必要条件是哈密顿函数的期望值无限逼近于其最大值。另一方面,利用Ekeland变分原理对哈密顿函数进行变分处理,得到当模型的最优逼近控制的期望值为哈密顿函数的上确界时,资产积累模型最优逼近控制是存在的。

A stochastic user equilibrium model solving overlapping path and perfectly rational issues

Traffic assignment has been recognized as one of the key technologies in supporting transportation planning and operations.To better address the perfectly rational issue of the expected utility theory(EUT)and the overlapping path issue of the multinomial logit(MNL)model that are involved in the traffic assignment process,this paper proposes a cumulative prospect value(CPV)-based generalized nested logit(GNL)stochastic user equilibrium(SUE)model.The proposed model uses CPV to replace the utility value as the path performance within the GNL model framework.An equivalent mathematical model is provided for the proposed CPV-based GNL SUE model,which is solved by the method of successive averages(MSA).The existence and equivalence of the solution are also proved for the equivalent model.To demonstrate the performance of the proposed CPV-based GNL SUE model,three road networks are selected in the empirical test.The results show that the proposed model can jointly deal with the perfectly rational issue and the overlapping path issue,and additionally,the proposed model is shown to be applicable for large road networks.

Cumulative prospect theory-based user equilibrium model with stochastic perception errors

The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic perception error(SPE) within travelers' route choice decision process is developed. The SPE is conditionally dependent on the actual travel time distribution, which is different from the deterministic perception error used in the traditional logit-based stochastic user equilibrium. The CPT-UE model is formulated as a variational inequality problem and solved by a heuristic solution algorithm. Numerical examples are provided to illustrate the application of the proposed model and efficiency of the solution algorithm. The effects of SPE on the reference point determination, cumulative prospect value estimation, route choice decision and network performance evaluation are investigated.

Post-Fertilization Development of Seed in French Bean Genotypes： Changes in Seed Quality

An experiment was conducted to evaluate physiological maturity of French bean genotypes at District Seed Farm ＂D＂ Block, Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal during winter season of both 2012-2013 and 2013-2014. All the five genotypes were grown with sufficient population in three replications following randomized block design （RBD） for the purpose of developmental studies. Developing pods were harvested at different stages, starting from 7 days after anthesis （7 DAA） to 49 DAA with an interval of 7 d, including the field maturity stage, thus leading to study on maximum seven different stages. Harvested pods and seeds were utilized for this development programme through dry seed weight, germination and vigour index. Enhancement in dry matter accumulation in seed continued till 42 DAA for Selection 9 and Victoria in both the years; it was 49 and 42 DAA for Sonali in respective years; it was 49 DAA for Abhay in both the years; and for Deepali, it was 42 DAA along with statistically similar magnitude at 49 DAA. Significant enhancement in germination potential of developing seeds continued till 42 DAA for Selection 9 and Deepali, while it was 49 DAA for the other three genotypes. Enhancement in vigour index continued till 49 DAA for all the genotypes except for Selection 9, for which it continued till 42 DAA and then declined.

Effects of Row Spacing on Component, Biomass and Energy of Elymus sibiricus L.

In the study, E. sibiricus L. cv. chuancao No. 2 was allocated to plots in a randomized block design with five row gradients （30, 45, 60, 75 and 90 cm）. At the flowering stage, the root, stem, leaf and inflorescence of population, as well as the quantitative traits of components, biomass structure, accumulation and distribution proportion of energy were measured and analyzed. For different row spacings, there are highly significant differences between total tillers and ratio of fertile tillers per square meter and significant differences among the eustipes length, eustipes number and natural height of each tiller; but there are no significant differences among the leaf length, leaf width and leaf number of each tiller. A significant difference is found between the depth and distribution range of root, inflorescence stalk, and ear number of fertile tillers, and the biomass of leaf, stem, root and inflorescence. The influenced order is stem 〉 leave 〉 root 〉 inflorescence. No significant influence is found among the energy values of single leaf, stem, root and inflorescence; but a significant influence is found among the energy accumulation of the leaf, stem, root and inflorescence with the effect degree being stem 〉 leaf 〉 inflorescence 〉 root. Significant differences are also found among the energy distribution of each component with the order of leaf〉 stem 〉 inflorescence 〉 root.

The CDF and its sensitivity analysis of stochastic structure with stochastic excitation by advanced stratified line sampling

For the stochastic structure with stochastic excitation, an advanced stratified line sampling (SLS) method is presented to obtain the cumulative distribution function (CDF) of the structural response and its sensitivity. The advanced stratified line sampling method introduces a set of middle failure subsets firstly. And for each subset, the conventional line sampling can be used to obtain the corresponding value of the response's CDF. At the same time, the sensitivity estimations of each failure subset can also be computed by modifying the important direction and corresponding reliability coefficients. The properties of CDF sensitivity are proved while the performance function is linear with normal random variables. After two simple examples are used to demonstrate the properties of CDF sensitivity and the feasibility of the presented method, the method employed to analyze the CDF and corresponding sensitivity of root bending moment (RBM) responses for the stochastic BAH is wing with gust excitation to a square-edged gust and to a Dryden gust. The results show that the parameters of the second and the fifth order modals exert more influence on the CDF of response than the other ones, and the presented SLS method can more significantly reduce the computational cost compared with Monte Carlo simulation (MCS).

Optimal Military Spending,Trade and Stochastic Economic Growth

Based on the procedure of dynamic programming,this paper investigates the military spending,trade and wealth accumulation in a stochastic endogenous economic growth model.For the Cobb-Dauglas utility function,explicit solutions of the optimal problem of the home country are obtained.Meanwhile,the optimal consumptions of domestic goods and foreign goods,the share of domestic capital stock and foreign bond holdings are derived explicitly.The comparative dynamic analysis shows that when intertemporal substitution in consumption is relative elastic,economic growth has a positive correlation with foreign military spending,has a negative correlation with variance of foreign military spending,and has a positive correlation with variance of capital or bonds if capital and bonds yields the same benefits.However,in the case of inelasticity,variance of foreign military spending may stimulate or weaken economic development.