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931.
云计算及其在智能交通上的应用 总被引:2,自引:0,他引:2
智能交通系统是交通和信息技术融合的产物。近年来,交通和信息技术都发生了很大的变化,信息大集中模式的云计算中心的建设也成为了必然的趋势。文章通过某市智能交通项目实践将两者的最新发展相结合,提出"智能交通云"的概念。可为以后实际工程规划、设计提供全方位的参考。 相似文献
932.
微弱目标的检测对雷达系统和检测方法提出很高的要求。首先采用速度检索和相位检索的方式,优化了基于相参积累的检测前跟踪算法;其次建立了简单的回波信号模型,分析了该算法的基本原理,探讨了该算法在当前条件下的可行性和局限性。实验仿真了目标幅度在帧间非起伏情况下目标的航迹规划,并且对其作了性能分析。实验表明,建立在距离-多普勒坐标系下的相参积累的算法,减少了搜索量和计算量,增加了信噪比的同时,取得了很好的航迹效果。 相似文献
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将改进人工鱼群- BP神经网络混合算法(RAAFSA - BP)应用于景观生态规划方法中,建立了景观生态规划的RAAFSA - BP模型,对城市景观进行规划和评价.结果表明,该算法泛化能力强,预测精度显著提高,为景观格局预测、模拟分析及景观规划提供了一种有效的方法. 相似文献
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937.
Güngör Gündüz 《The Journal of mathematical sociology》2013,37(3):167-187
In this work, mathematical models for the growth of the Ottoman and Roman Empires are found. The time interval considered for both cases covers the time from the birth of the empire to the end of the fast expansion period. These empires are assumed to be nonlinearly growing and self-multiplying systems. This approach utilizes the concepts of chaos theory, and scaling. The area governed by the empire is taken as the measure of its growth. It was found that the expansion of each empire on lands, seas, and on both (i.e., lands+seas) can be expressed by power laws. In the Ottoman Empire, the nonlinear growth power of total area is approximately equal to the golden ratio, and the nonlinear growth power of the expansion on lands is approximately equal to the square root of 2. In the case of the Romans, some numbers associated with the golden ratio, or the square root of 2, appear as the power of the nonlinear growth term. The appearance of both the golden ratio and the square root of 2 show that both empires had intention on achieving stability during their growth. 相似文献
938.
This paper proposes a procurement and production outsourcing model subject to a dynamic prices environment. Using the optimal control theory we obtain the necessary conditions of the optimal procurement and production policy. From the study of optimal control conditions, we derive qualitative properties of the optimal procurement and production decisions for a few exemplifying cases. Through these results we are able to provide some managerial implications for managers to make real decisions. 相似文献
939.
Thomas Volling Andreas Matzke Martin Grunewald Thomas S. Spengler 《European Journal of Operational Research》2013
In an attempt to achieve a competitive edge, automotive companies operate global production networks to offer an ever increasing product variety, shorter and reliable lead times as well as competitively priced products. Cars are no longer exclusively produced based on standardized product configurations and stable sales plans but are increasingly build-to-order to match the needs of individual customers. Operations Research (OR) may contribute towards successful build-to-order operations. This is likewise reflected by the appreciable number of published papers on industry specific OR applications. To provide readers with an overview about these OR models and applications we identify current and future research issues based on the review of 49 works. We focus on two important planning objects which have not been considered in prior reviews: the planning of capacities and orders. To bridge the gap between conceptual works on the one hand and quantitative contributions on the other, we provide a framework for the structuring of planning tasks. Existing models are classified according to this framework and open issues that should be addressed in OR are discussed. 相似文献
940.
In the rectangle packing area minimization problem (RPAMP) we are given a set of rectangles with known dimensions. We have to determine an arrangement of all rectangles, without overlapping, inside an enveloping rectangle of minimum area. The paper presents a generic approach for solving the RPAMP that is based on two algorithms, one for the 2D Knapsack Problem (KP), and the other for the 2D Strip Packing Problem (SPP). In this way, solving an instance of the RPAMP is reduced to solving multiple SPP and KP instances. A fast constructive heuristic is used as SPP algorithm while the KP algorithm is instantiated by a tree search method and a genetic algorithm alternatively. All these SPP and KP methods have been published previously. Finally, the best variants of the resulting RPAMP heuristics are combined within one procedure. The guillotine cutting condition is always observed as an additional constraint. The approach was tested on 15 well-known RPAMP instances (above all MCNC and GSRC instances) and new best solutions were obtained for 10 instances. The computational effort remains acceptable. Moreover, 24 new benchmark instances are introduced and promising results are reported. 相似文献