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41.
对于图G的正常k-全染色f称为G(V,E)的k-均匀全染色,当且仅当任意2个色类中的元素总数至多相差1.χet(G)=min{k|G有k-均匀全染色}称为图G的均匀全色数.利用均匀边染色的相关结论,讨论并得到了图Sn+Fn和Sn+Wn的均匀全色数. 相似文献
42.
文章结合海南大学图书馆实施全面质量管理下地方文献编目质量的监控措施,阐述TQM下的编目质量管理体系、工作流程监控机制、质量审查与控制措施等,通过地方文献编目质量的持续改进机制,以ISO标准提升图书馆服务。 相似文献
43.
电子及通信设备制造业区域创新绩效演化研究 总被引:1,自引:0,他引:1
为探究电子及通信设备制造业的区域创新效率的差异,运用DEA方法中的BCC模型,基于2015年我国24个省级行政区域的截面数据测算电子及通信设备制造业区域创新的综合效率、规模效率和纯技术效率;运用DEA-Malmquist方法基于2009—2015年的面板数据评价各地区与四大综合经济区电子及通信设备制造业的技术创新绩效变化情况如技术效率的变化、技术进步与规模效率的变化以及全要素生产率。研究成果对电子及通信设备制造业的区域创新发展具有参考价值,最后对具体问题提出相应的政策建议。 相似文献
44.
Least squares support vector machines (LS-SVMs) are modified support vector machines (SVMs) that involve equality constraints and work with a least squares cost function, which simplifies the optimization procedure. In this paper, a novel training algorithm based on total least squares (TLS) for an LS-SVM is presented and applied to multifunctional sensor signal reconstruction. For three different nonlinearities of a multifunctional sensor model, the reconstruction accuracies of input signals are 0.00136%, 0.03184% and 0.504 80%, respectively. The experimental results demonstrate the higher reliability and accuracy of the proposed method for multifunctional sensor signal reconstruction than the original LS-SVM training algorithm, and verify the feasibility and stability of the proposed method. 相似文献
45.
The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption ( V O 2peak ) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev·min -1 . The order of tests was randomized and they were separated by at least 2 days. Peak V O 2 was significantly higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Peak ventilation volume increased as a function of crank rate and was higher ( P ? 0.05) at 80 than at 60 rev·min -1 . Peak heart rate was higher ( P ? 0.05) at 70 and 80 rev·min -1 than at 60 rev·min -1 . Furthermore, 70 and 80 rev·min -1 resulted in an extended test time compared with 60 rev·min -1 . The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev·min -1 should be used to elicit V O 2peak and other physiological responses in arm crank ergometry. 相似文献
46.
基于Global-Malmquist-Luenberger指数的中国水资源全要素生产率增长评价 总被引:4,自引:2,他引:2
基于省际水足迹和灰色水足迹等的面板数据,本文利用带有“非期望”产出的数据包络分析方法,通过Global-Malmquist-Luenberger指数测度了1998年-2010年中国31个省、区、直辖市的水资源全要素生产率增长并分解为纯技术效率变化、技术进步和规模效率变化.研究发现:①不考虑非期望产出的水资源全要素生产率增长高于考虑非期望产出的水资源全要素生产率;②非期望产出情况下的水资源全要素生产率增长明显具有正的空间集聚现象,且非常显著;③中国31个省、区、直辖市水资源全要素生产率增长主要源于技术进步,纯技术效率和规模效率出现恶化,波动变化都很小.在此基础上对中国水资源利用效率健康发展提出了相应的政策建议. 相似文献
47.
介绍了免棱镜全站仪的工作原理及优缺点,对Leica TS06全站仪在无反射棱镜条件下的测距性能进行了测试,得出了测距边长、测量目标的属性对免棱镜测距的影响关系,介绍了免棱镜全站仪在工程项目测量中的应用实例。 相似文献
48.
茶叶细胞壁总糖的测定 总被引:1,自引:0,他引:1
郭俊明 《蒙自师范高等专科学校学报》1997,(4)
茶叶细胞壁经72%H_2SO_4处理三小时后,用水稀释成农度为1mol·dm~(-3)LH_2SO_4溶液,热回流水解12小时以上,再经BaCO_3固体中和、过滤、减压浓缩到小体积并定容到一定的准确体积。按硫酸-酚法(490nm)测得茶叶细胞壁总糖含量为35.8%。本法为测定植物细胞壁总糖提供了一个较好的方法。 相似文献
49.
高中学业水平考试研究(二):考试质量评价 总被引:1,自引:0,他引:1
学业水平考试试题和试卷的质量直接影响学业评价和诊断结果的有效性和可靠性。本文以上海市高中思想政治学科学业水平考试为例,从试题和题组功能偏差、试题得分与总分的相关系数、识别指数分析及分类一致性和准确性四个方面对考试的质量进行了定量评价,以介绍学业水平考试质量评价的方法。 相似文献
50.
Ines Ben Chobba Amine Elleuch Imen Ayadi Lamia Khannous Ahmed Namsi Frederique Cerqueira Noureddine Drira Néji Gharsallah Tatiana Vallaeys 《Journal of Zhejiang University. Science. B》2013,14(12):1084-1099
Endophytic flora plays a vital role in the colonization and survival of host plants, especially in harsh environments, such as arid regions. This flora may, however, contain pathogenic species responsible for various troublesome host diseases. The present study is aimed at investigating the diversity of both cultivable and non-cultivable endophytic fungal floras in the internal tissues (roots and leaves) of Tunisian date palm trees (Phoenix dactylifera). Accordingly, 13 isolates from both root and leaf samples, exhibiting distinct colony morphology, were selected from potato dextrose agar (PDA) medium and identified by a sequence match search wherein their 18S–28S internal transcribed spacer (ITS) sequences were compared to those available in public databases. These findings revealed that the cultivable root and leaf isolates fell into two groups, namely Nectriaceae and Pleosporaceae. Additionally, total DNA from palm roots and leaves was further extracted and ITS fragments were amplified. Restriction fragment length polymorphism (RFLP) analysis of the ITS from 200 fungal clones (leaves: 100; roots: 100) using HaeIII restriction enzyme revealed 13 distinct patterns that were further sequenced and led to the identification of Alternaria, Cladosporium, Davidiella (Cladosporium teleomorph), Pythium, Curvularia, and uncharacterized fungal endophytes. Both approaches confirmed that while the roots were predominantly colonized by Fusaria (members of the Nectriaceae family), the leaves were essentially colonized by Alternaria (members of the Pleosporaceae family). Overall, the findings of the present study constitute, to the authors’ knowledge, the first extensive report on the diversity of endophytic fungal flora associated with date palm trees (P. dactylifera). 相似文献