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131.
为了均衡终端区扇区的工作负荷,保障扇区边界的合理性,研究了终端扇区的划分方法.针对建立的扇区划分数学模型,提出了3阶段的划分方法.首先,采用voronoi图和遗传算法完成初始划分,实现均衡负荷的目标;其次,提出了基于voronoi图和基于maklink图的2种扇区二次划分方法,满足最小飞行时间及最小距离约束;最后,应用分段线性拟合的方法消除扇区边界的锯齿状,以及满足扇区凸形约束.以广州终端为例进行了仿真计算.应用提出的方法,给出了2种划分结果,都能够使得各扇区的工作负荷在2880s以内,差值不超过350s,扇区边界较为平滑,且计算时间明显减少.仿真计算结果说明方法是可行和有效的,也为使用者提供了灵活的选择. 相似文献
132.
酸性红黄壤土上大麦遗传改良研究 总被引:2,自引:0,他引:2
本文报道了酸性红黄壤土上大麦遗传改良研究结果:(1)采用酸铝营养液培养幼苗的方法鉴定了我国3871份大麦品种的耐酸铝性,得到一级耐性材料315份,占鉴定总数的8.13劣,(2)相关通径分析表明,酸性红黄壤土上大麦单株籽粒产量损失起主要作用的是有效分菜数下降(P = 0. 7324 )、每穗实粒数减少(P = 0 . 5923 )和千粒重降低(P = 0.5877),由此可见,这是在红黄壤土田间条件下选择耐酸铝性大麦的三个主要选择指标;(3)发现大麦耐酸铝性基因遗传方式除单基因遗传方式外,尚有多基因控制的表现数量性状遗传方式;'(4)从对酸铝性表现敏感的大麦品种“早熟3一号”的花药、幼胚等外植体诱导出的愈伤组织,通过离体细胞突变体筛选,得到了“耐性细胞系”.以上结果表明,通过耐酸铝性遗传改良培育出适应酸性红黄壤土种植的大麦新品种是可行的,亦为开发利用红黄壤土地资源补充了另一条有效途径. 相似文献
133.
刘正春 《数学的实践与认识》2004,34(6):32-37
基于 APT理论 ,在不允许卖空、并考虑交易成本的情况下 ,本文建立了多因素证券组合投资决策模型 ,然后利用遗传算法研究了模型的求解 相似文献
134.
《Optimization》2012,61(3):687-707
This paper proposes an optimization method for a national-level highway project planning based on a modified genetic algorithm. The proposed method adds to the existing methods by integrating various planning elements into a single system. A simulation model is used in order to determine the best investment strategy with regard to net present value, time deviation from the initial plan and discrepancy between available resources and investment costs by taking into account economical, social, traffic and political factors. The outcome is a project schedule with an optimized cash flow. The proposed method was tested using the example of the National Highway Programme in Slovenia. 相似文献
135.
136.
Kiyotsugu Takaba Yutaka Ichihara 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(4):377-396
This paper considers the initial value problem of an interconnection composed of linear systems described by the first-order differential/algebraic equations (DAEs). An initial condition of the system variable for which the DAE has a solution is called admissible. For the interconnected system, we formulate the invariance of the admissible initial condition sets (AICSs) of the sub-systems under interconnection. Namely, the AICSs are said to be invariant if they remain unchanged even when additional constraints due to interconnection are imposed on the system variables. It is shown that the feedback and regular feedback structures of the interconnection guarantee the invariance of the AICSs in the senses of impulsive-smooth distributions and smooth distributions, respectively. The results in this paper justify the use of a feedback controller in the control system design. 相似文献
137.
M. Hosseinpour P. Nikdel M.A. Akbari 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):250-262
This article proposes a Takagi–Sugeno (T-S) fuzzy model of single-link rotary flexible joint robot. The proposed control method is based on parallel distributed control. The parameters of T-S controller are improved by distributed population genetic algorithm (GA) with chaos GA. Using Hermite–Biehler theorem in distributed population, GA is made to have a fast convergence. Dividing search space into several sub-spaces causes a better response, and chaos disturbance helps the whole algorithm to reach a best answer. The stability of the controller is analysed via the sum of squares programming, and finally, it is implemented on the plant. 相似文献
138.
Karl-Gustaf Lüfgren 《Natural Resource Modeling》1990,4(4):477-494
The paper contains an extension of existing results on the economics of tree improvement programs. The properties of the indirect utility function and the present value function are used to derive general equilibrium and disequilibrium cost–benefit rules for marginal projects resulting in an improved production function. Corresponding results for projects resulting in large second order effects in both prices and quantities are also provided, and indirect methods to estimate the net benefits are suggested. It is also briefly discussed how recreational and option values can be dealt with. 相似文献
139.
Herbert Gintis 《Computational & Mathematical Organization Theory》1997,3(1):19-41
The paper generalizes the Kiyotaki-Wright trade model by treatingthe trading period as a finite game, so Nash's theorem can be used to provethe existence of equilibrium, and by treating the economy as a Markovprocess, so an ergodic theorem can be used to show the existence ofequilibria with desirable properties (e.g., in which money exists). A Markovmodel of trade also allows us to add complexity to the economy withoutadding corresponding complexity to the analysis of the model's properties.The paper also provides artificial life simulations of the Markov economysuggesting that monetary equilibria are dynamically stable and do notrequire high levels of learning or information processing on the part ofagents. 相似文献
140.
基于遗传算法的静态Ad-hoc拓扑结构控制 总被引:2,自引:0,他引:2
将遗传算法引入到了静态Ad—hoc无线网络的拓扑结构控制中,突破了网络中所有节点辐射半径都相同的固有思路,通过调节各无线节点的辐射半径,在相邻节点对之间形成有向路径,从而达到节省节点能源消耗和网络拓扑结构优化的目的,并取得了较好的实验结果。 相似文献