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91.
项目规划及执行过程中极易出现不确定性,故需对项目关键链缓冲区间进行动态调整以适应项目任务关系变化.针对项目计划关键链缓冲区间设置及调整控制问题,本文提出了一种考虑多因素扰动的缓冲设置及调整控制联动模型.项目初始缓冲设置充分考虑项目工序安全工期、网络复杂程度及资源紧张程度等因素影响,项目执行过程中将缓冲/资源绩效指数与Bayes估计相结合,通过对Weibull分布参数估计实现缓冲信息的递阶转换,提升对缓冲使用的控制能力,最后通过实例验证所提方法与控制模型的有效性. 相似文献
92.
INTELLIGENT SECURITY SYSTEMS ENGINEERING FOR MODELING FIRE CRITICAL INCIDENTS: TOWARDS SUSTAINABLE SECURITY 总被引:2,自引:0,他引:2
An intelligent security systems engineering approach is used to analyze fire and explosive critical incidents, a growing concern
in urban communities. A feed-forward back-propagation neural network models the damages arising from these critical incidents.
The overall goal is to promote fire safety and sustainable security. The intelligent security systems engineering prediction
model uses a fully connected multilayer neural network and considers a number of factors related to the fire or explosive
incident including the type of property affected, the time of day, and the ignition source. The network was trained on a large
number of critical incident records reported in Toronto, Canada between 2000 and 2006. Our intelligent security systems engineering
approach can help emergency responders by improving critical incident analysis, sustainable security, and fire risk management. 相似文献
93.
河南棉花新品种数量性状的典型相关和通径分析 总被引:1,自引:0,他引:1
通过对河南省2006年春棉品种区试10个品种的产量、植株及纤维品质性状组的典型相关与通径分析得出:选择生育期短、株高中等偏高、果枝节位低、果枝台数多的性状,有利于增加株铃,提高铃质量,并能间接增进主要纤维品质,确为选育高产优质棉花新品种的有效途径。但在选择结铃性强的植株性状时,应防止降低铃质量。从性状相关性间接选择对衣分无效,应通过室内考种择优选取。表11,参11。 相似文献
94.
To design approximately linear-phase complex coefficient finite impulse response (FIR) digital filters with arbitrary magnitude and group delay responses, a novel neural network approach is studied. The approach is based on a batch back-propagation neural network algorithm by directly minimizing the real magnitude error and phase error from the linear-phase to obtain the filter’s coefficients. The approach can deal with both the real
and complex coefficient FIR digital filters design problems. The main advantage of the proposed design method is the significant reduction in the group delay error. The effectiveness of the proposed method is illustrated with two optimal design examples. 相似文献
95.
New computing method of weighted coefficients for tracking a maneuvering target using PDAF in the presence of clutter 下载免费PDF全文
To avoid or reduce the influence of unpredictable motion mode on data association, a new computing method of weighted coefficients of measurements for PDAF is presented in which it is assumed that the current turn rate of a maneuvering target changes within a limited range and its turn may be in arbitrary direction during data association. Thus, the predicted center for computing the weighted coefficients is a curved surface in 3-D
space, which differs from the predicted center for setting up a validation gate, namely, a point in 3-D space. The distance between a measurement and the curved surface is used to compute its weighted coefficient. To reduce the computational complexity of weighted coefficients, the formulas for computing the maneuvering direction angle and turn rate corresponding to a measurement are presented. Simulation results show the proposed method reduces the percentage of lost tracks and improves the state estimation accuracy in tracking a maneuvering target using PDAF in the presence of clutter. 相似文献
96.
97.
The authors propose a V
N, p
test statistic for testing finite-order serial correlation in a semiparametric varying coefficient partially linear errors-in-variables
model. The test statistic is shown to have asymptotic normal distribution under the null hypothesis of no serial correlation.
Some Monte Carlo experiments are conducted to examine the finite sample performance of the proposed V
N, p
test statistic. Simulation results confirm that the proposed test performs satisfactorily in estimated size and power.
This research is supported by the National Natural Science Foundation of China under Grant Nos. 10871217 and 40574003; the
Science and Technology Project of Chongqing Education Committee under Grant No. KJ080609; the Doctor's Start-up Research Fund
under Grant No. 08-52204; and the Youth Science Research Fund of Chongqing Technology and Business University under Grant
No. 0852008. 相似文献
98.
To study simultaneous location of different kinds of facilities, a new model of flow interception problem with multi-type of flows is proposed, with the consideration of multi-purpose flows and the influence of facilities on each other. To be more practical, the objective is to maximize the benefits from flow-by customers instead of maximizing flows in the past. Since this problem is NP-hard and there is no optimal solution for large network, greedy and improved greedy heuristic algorithms are proposed. A computational example is presented to show that the optimal location decisions are proved to be strongly dependent on the influence coefficients and average profits by one customer and different types of facilities are almost co-located. Finally the results of sensitivity analysis are reported. 相似文献
99.
提出了一个演化的权重无标度网络模型.在传统的加权网络模型的强度优先连接机制基础上,考虑了网络按照模块结构和三角结构进行演化的特性.研究了模块结构和三角结构的演化机制对无标度模型结构特性的影响.仿真结果表明该权重网络的度、强度和权值都服从幂率分布,网络的平均强度与度之间具有高相关特性,网络的平均簇系数与度的函数关系服从幂率分布,模块结构和三角结构的演化机制能够显著提高网络的簇系数. 相似文献
100.