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11.
对界限含水量的测定表明,玉树隆宝湖地区的粘性土,由东至西粘性逐渐增强,可塑性也随之增大,其塑性指数在10左右;并作了土质评定。  相似文献   
12.
研究求解一类对称双正型的线性互补问题的EAOR迭代算法.证明了由此算法产生的迭代序列的聚点是线性互补问题的解.并且,当互补问题中的矩阵为对称双正加阵或严格对称双正阵时,算法产生的迭代序列存在子序列收敛到互补问题的解.而当矩阵为非退化对称双正加阵时,该序列收敛.  相似文献   
13.
广义正定矩阵的几个注记   总被引:1,自引:0,他引:1  
给出了广义正定矩阵与稳定矩阵的关系,广义正定矩阵Kronecker积的特征值性质和广义正定矩阵的逆矩阵的性质。改进了近期广义正定矩阵的一些结果。  相似文献   
14.
Metals have been constantly introduced to urban environments via various point and non-point sources of pollution,and have contaminated different urban compartments(sample types).However,most research projects have focused on a single environmental compartment to characterize urban metal contamination.In the present study,an integrated sampling program that includes surface soils,different size fractions of soil and road dust(<50 μm,50-100 μm,100-250 μm,and 250-1000 μm),tree leaves,and grasses,was conducted in a typical urban area of Guangzhou,China.The aim of the study was to investigate the interrelationships among the metal pollutants in these samples.The concentrations of trace metals varied greatly among different sample types,and their distribution was generally in the following order:road dust > soil dust ≥ surface soils ≈ top soils > grasses ≥ tree leaves.As for the relationships among the trace metals,different combinations were seen among the sample types,indicating different loadings of trace metals in the sampling medium.Significant correlations of metal concentrations were found between tree leaves and the smallest(<50 μm) fraction of road dust,and between soil dust(50-100 μm) and surface soils,suggesting that trace metals in these samples may influence each other.  相似文献   
15.
A phylogenetic analysis of members of the family Buccinidae was conducted using 18S rRNA gene, 28S rRNA gene and the mitochondrial cytochrome oxidase Ⅰ gene. We studied 18 species of Buccinidae that belong to eight different genera and inhabit the China coastal seas. We analyzed the patterns of divergence between an outgroup and basal ingroup taxa, the monophyly of the genus Neptunea, and the position of one unnamed species within the Buccinidae. A phylogenetic tree (neighbor-joining (NJ) method) was reconstructed based on the sequences of 18S rRNA, 28S rRNA and COI, with Rapana venosa as outgroup. The NJ tree indicated that the 18 species could be divided into five groups. The genus Buccinum was monophyletic, whereas Neptunea was shown to be paraphyletic since it included Siphonalia subdilatata and Neptunea sp., a new species. This novel species otherwise clustered consistently with Neptunea cumingi in three other phylogenetic trees, showing a low genetic distance and divergence percentage of sequences belonging to the genus Neptunea. A smaller genetic distance and a smaller difference of 18S rRNA, 28S rRNA and COI sequences between Neptunea cumingii and Neptunea arthritica cumingii confirmed them to be the same species.  相似文献   
16.
为提升多无人地面平台协同控制能力,适应新形势下智能战争趋势,基于JADE和World Wind Java构建了多智能体地面平台协同控制仿真系统。运用多Agent理论建立无人地面平台仿真模型,基于JADE构建协同控制仿真平台,运用粒子群算法优化任务分配机制。仿真实验表明,构建的协同控制仿真平台具有良好的鲁棒性和灵活性,优化后的任务分配机制使得多无人地面平台群体执行任务效率明显提高,且可应用于其他海上、空中无人平台的仿真研究。  相似文献   
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