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61.
62.
信息不完全共享下MC供应链动态调度模型研究 总被引:3,自引:2,他引:3
为解决信息不完全共享环境下,大规模定制供应链的动态调度问题,提出了基于蚁群算法的多企业交互调度模型.模型中,供应链企业均具有各自独立的异构生产调度系统,企业在互不了解完全生产信息的情况下,通过企业代理之间的反复、自动交互,对订单任务分配及合作时序进行协调,从而实现供应链动态优化调度.仿真实验证明,此模型具有良好的调度效果和稳定性. 相似文献
63.
提出一种新的蚁群算法(Multiple Ant Colonies Algorithm based on Sweep Algorithm, SbMACA)用以求解车辆路径问题(Capacitated Vehicle Routing Problem, CVRP)。该方法同以往蚁群算法的不同之处主要体现在两个方面:第一,首次将扫描算法应用于蚁群算法,通过对蚂蚁所构造的初始解中的不同子回路之间的点进行交换优化,该算法可以有效地改进初始解的质量;第二,提出并采用了一种新的多蚁群技术,各个蚁群分别进行各自的搜索,在各个蚁群均停滞后,对蚁群之间的信息素进行交换与更新,以利于蚁群跳离局部最优值。实验结果表明,SbMACA算法具有很强的搜索能力,求取各CVRP的Benchmark问题所得解的质量同最好解相比较而言,平均仅有 0.28%的差距,是求解车辆路径问题的一种十分有效的方法。 相似文献
64.
65.
给出了基于蚁群算法实现机器人足球比赛中球员之间协作和通信的机制.选用两只球队分别采用了传统的通信机制和"黑板"通信机制进行实验比较,发现虽然两个球队的整体结构和高层策略相差无几,但是无论从速度、力量还是传接球成功率等方面,Novauro都比ujdb强.该通信机制具有灵活,鲁棒性强的特点,不会由于局部的失误而影响全局的性能. 相似文献
66.
《Journal of Natural History》2012,46(19-20):1325-1337
The pre-overwintering nest structure and the immature stages of the hornet Vespa fumida van der Vecht are for the first time reported. All three adult forms (queen, worker and drone) are briefly described. The eggs have many micropyles concentrated at the larger end of the egg. The mature larvae can be identified by having the ecdysial sulcus obliterated ventrally; the parietal band distinctly margined ventrally on the outer side; the palate with a median patch and a pair of dorsal patches; the collar processes of the spiracle long and thick, with many branches over almost all the surface. Morphology and distribution of the different types of sensilla (setae, conical papillae, campaniform sensilla, basiconic sensilla, etc.) and the spicules are illustrated in detail. Close relationship between the Vespa affinis-group and V. fumida previously suggested by adult morphology is briefly discussed in terms of the morphology of the mature larvae. 相似文献
67.
《Journal of Natural History》2012,46(19-20):1139-1145
Many epiphytic ferns in tropical forest canopies have domatia that provide habitat for arboreal arthropods such as ants. Two species of fern that were predominantly occupied by Crematogaster difformis ants were collected from the canopy of a forest in Borneo. In the fern domatia, two cockroach species, Pseudoanaplectinia yumotoi and Blatta sp., were found to live with C. difformis. Pseudoanaplectinia yumotoi were found in large numbers and accounted for approximately 20% of the total arthropod population, while Blatta sp. comprised only 1% of the arthropods living in the domatia. Behavioural experiments were conducted to evaluate the response of C. difformis workers to newly introduced cockroaches of each species and to allospecific ant workers. Crematogaster difformis workers were highly aggressive and quickly attacked allospecific workers. Both cockroach species could fend off ant attacks; however, dead Blatta sp. were often attacked by the ants while dead P. yumotoi were infrequently bothered. 相似文献
68.
设N是一个赋范线性空间X上的套,m(N)是N到N的映射全体所成的集合,记m0(N)={α∈m(N)|α(0)=0,α左连续且保序}。对于子空间M,首先表明下面命题是等价的:(1)M是弱闭的AlgN-模;(2)存在α∈m0(N)使M=Mα;(3)存在β∈m(N)使M=Mβ。假使N最多只包含3个元素,那么所有的AlgN-模可全部被列举出来;假如N至少包含4个元素,那么下面命题是等价的:(1)0<0+且X-相似文献
69.
《Journal of Natural History》2012,46(15-16):979-1003
We analysed the arthropod fauna from nine nests of Cacicus sp. and nine nests of Psarocolius sp. (Passerida: Icteridae), in the varzea forest of Central Amazonia, Brazil, during high water, establishing these nests as one of the probable refuges for several arthropods performing vertical migration during periods of flooding and high water, besides discussing the role of these arthropods in the nests. We also evaluate the effectiveness of the extraction of arthropods from nests using an apparatus based on the Berlese–Tullgren funnel. We obtained 15,128 arthropods from three subphyla, five classes and 16 orders. The nests were shown as complex ecosystems sheltering groups from different functional and trophic categories and revealed striking differences from those of terra firma, remarkably in Blattaria, Arachnida and Pseudoscorpiones. The increasing volume of the funnel and time of heat exposure was shown to be appropriate for extraction of the arthropods from the bulky nests of these birds. 相似文献
70.
A new problem of degree-constrained Euclidean Steiner minimal tree is discussed, which is quite useful in several fields. Although it is slightly different from the traditional degree-constrained minimal spanning tree, it is also NP-hard. Two intelligent algorithms are proposed in an attempt to solve this difficult problem. Series of numerical examples are tested, which demonstrate that the algorithms also work well in practice. 相似文献