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1.
物流路径优化问题是物流研究领域十分重要的研究课题。针对物流企业对物流配送时间、距离以及运输成本的要求不同,建立带目标权重的物流路径数学模型,物流企业可对目标权重进行赋值进而满足自身的需求。针对基本蚁群算法易陷入局部最优以及收敛速度慢的缺陷,对基本蚁群算法的转移规则和信息素进行改进,然后在改进的基本蚁群算法中融入模拟退火算法思想,建立模拟退火蚁群算法。实验结果表明:模拟退火蚁群算法能搜寻到比基本蚁群算法更优的综合成本,且收敛速度更快,同时也表明模拟退火蚁群算法的可行性及数学模型的合理性。  相似文献   

2.
为了克服基本蚁群算法搜索时间过长,易陷于局部最优等缺点。引入了随机算法,并提出了一种采用随机模式调整信息素的改进蚁群算法RACA(Randomized Ant Colony Algorithm)。采用随机地计算部分点的函数值,并对当前最优、次优解的部分解启用新的信息素调整规则。该算法保持了解的多样性,增强了全局搜索的能力。运算结果表明新的蚁群算法对求解连续函数优化问题有较好的改进效果。  相似文献   

3.
协同设计中的任务调度算法及实现   总被引:1,自引:0,他引:1  
 在协同设计子任务间形成的任务前趋图的基础上,面向协同设计的实际需求,采用了两个任务调度算法:改进的AGA(Adaptive Genetic Algorithm, 自适应遗传算法)及GASA(Genetic Simulated Annealing Algorithm,遗传-模拟退火算法)。分别给出了算法的详细实现,分析并比较了算法与其它任务调度算法的效能。最后,针对较大规模的任务实例对这两个算法进行了横向比较,分析了它们的时间效率和适用场合。  相似文献   

4.
针对传统的蚂蚁算法容易出现早熟和停滞现象,提出了一种自适应蚂蚁算法(Self-Adaptive Ant Colony Algorithm,SAACA)并选择典型TSP问题进行实验.结果表明:改进的蚁群算法具有更好的搜索全局最优解的能力以及更好的稳定性和收敛性.  相似文献   

5.
智能混合优化策略及其在流水作业调度中的应用   总被引:5,自引:1,他引:4  
通过结合蚁群算法(ACO)的并行搜索结构和模拟退火算法(SA)的概率突跳性,提出了一种有效的混合优化策略,并将该策略应用于流水作业调度问题(FSP).在该策略中,蚁群系统的一个周游路线为模拟退火算法提供了一系列初始解,在每个退火温度上进行抽样准则检验并产生新解,然后更新信息激素;蚁群算法再利用模拟退火算法产生的新解进行并行搜索.同时,根据此策略构建并实现了针对FSP问题求解的具体混合算法.仿真结果表明,混合算法弥补了ACO易陷入局部最优和SA搜索效率较低的缺点,增强了全局搜索能力,在求解FSP调度问题的性能上也优于其他算法。  相似文献   

6.
廖继红 《科技信息》2008,(29):231-232
本文从求解TSP来分析遗传算法,蚁群算法,模拟退火算法三种优化算法特性分析,总结各算法的改进策略及混合算法策略,并提出基于分区的混合算法。  相似文献   

7.
针对现有流程序自动综合技术中任务分配与调度方法效率低下的问题,提出一种基于改进蚁群算法的多核任务分配与调度算法.基于建立的问题模型,改进了基本蚁群算法中的信息素更新规则和启发式信息的计算方法,并应用多样化机制避免算法早熟收敛.为了提高效率,算法创新地在确定任务分配方案的同时确定调度序列.以标准任务图集为试验对象,验证算法的有效性.试验结果表明:与模拟退火算法相比,使用改进的蚁群算法在优化程序的执行跨度时收敛速度较快,并且在相同的循环次数下,得到的解更接近最优解.  相似文献   

8.
郝会成 《科学技术与工程》2013,13(17):4972-4978
针对新一代对地观测敏捷卫星任务规划问题,首先研究了敏捷卫星的特点,分析了敏捷卫星工作模式及对地观测过程,在此基础上构建了基于多目标的任务规划模型。针对敏捷卫星任务规划问题具有多约束、多冲突、非线性NP-hard特点,本文提出了基于混合遗传求解算法,该算法将免疫遗传算法与蚁群算法相结合,以蚁群算法所产生的解作为免疫遗传算法的初始种群,同时以蚁群算法中的全局最优解作为疫苗。通过实验表明本文提出的算法比遗传算法和免疫遗传算法精度更高,收敛速度更快。  相似文献   

9.
为解决基于航迹运行(Trajectory Based Operation, TBO)模式下大规模航迹战略冲突解脱问题,建立了综合考虑最小化冲突数量和航迹调整成本的双目标优化模型.设计了基于超体积指标的多目标合作协同进化算法(Indicator-based Cooperative Coevolution Multi-objective Evolutionary Algorithm, IBCCMOEA)进行模型求解,采用非支配排序遗传算法(Non-dominated Sorting Genetic Algorithm II,NSGA-II)进行子种群优化.同时,设计了自适应遗传算子加快算法收敛速度.分别采用中国航路网络繁忙时段442架和1 014架航班历史飞行数据进行仿真验证,将所提算法与NSGA-II,基于分解的多目标进化算法(Multi-objective Evolutionary Algorithm Based on Decomposition, MOEA/D)以及多目标合作协同进化算法(Cooperative Coevolution Multi-objective Evolutio...  相似文献   

10.
针对二维下料问题板材单一的特点,研究了多规格板材二维下料问题。板材规格多样、毛坯规格多样且数量庞大,是NP(Non-deterministic Polynomial)完全问题。针对该问题的特点,将下料过程设计成规整和非规整两个阶段。规整阶段完成每种矩形毛坯的主体下料任务之后,如仍有毛坯剩余,则进入非规整阶段采用BL算法(Bottom Left Algorithm)下料剩余毛坯。根据模型特点,提出变邻域人工蜂群算法(VNABC),设计两种解码策略STD和SLD,并改进了VNABC算法的操作算子。最后,采用响应面分析法对VNABC算法进行参数标定。通过仿真实验将VNABC算法与遗传算法(GA)、改进粒子群优化算法(NUS)、模拟退火算法(SA)、人工蜂群算法(ABC)进行了对比分析,实验结果验证了VNABC解决多规格板材二维下料问题的优越性。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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