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71.
清代乾嘉时期常州女诗人庄盘珠的诗词作品,初有《秋水轩集》、《紫薇轩集》及《莲佩诗草》数种,以抄本形态存在,后《紫薇轩集》、《莲佩诗草》亡佚,《秋水轩集》以诗词分刻或合刊的不同形态流传至今。冒俊编校如不及斋本是目前最为完善的合刊本。  相似文献   
72.
对电子商务和现代物流的关系进行了论述,分析了电子商务环境下现代物流的主要发展模式:自建模式、TPL模式、物流一体化模式和共同配送模式。着重探讨了烟草行业中现代物流的发展状况,以及烟草行业在电子商务条件下发展现代物流的思路。  相似文献   
73.
Laplace Approximations for Natural Exponential Families with Cuts   总被引:1,自引:0,他引:1  
Standard and fully exponential form Laplace approximations to marginal densities are described and conditions under which these give exact answers are investigated. A general result is obtained and is subsequently applied in the case of natural exponential families with cuts, in order to derive the marginal posterior density of the mean parameter corresponding to the cut, the canonical parameter corresponding to the complement of the cut and transformations of these. Important cases of families for which a cut exists and the approximations are exact are presented as examples  相似文献   
74.
We show that good community structures can be obtained by partitioning a social network in a succession of divisive sparsest cuts. A network flow algorithm based on fundamental principles of graph theory is introduced to identify the sparsest cuts and an underlying hierarchical community structure of the network via maximum concurrent flow. Matula [Matula, David W., 1985. Concurrent flow and concurrent connectivity in graphs. In: Alavi, Y., et al. (Eds.), Graph Theory and its Applications to Algorithms and Computer Science. Wiley, New York, NY, pp. 543–559.] established the maximum concurrent flow problem (MCFP), and papers on divisive vs. agglomerative average-linkage hierarchical clustering [e.g., Matula, David W., 1983. Cluster validity by concurrent chaining. In: Felsenstein, J. (Ed.), Numerical Taxonomy: Proc. of the NATO Adv. Study Inst., vol. 1. Springer-Verlag, New York, pp. 156–166 (Proceedings of NATO ASI Series G); Matula, David W., 1986. Divisive vs. agglomerative average linkage hierarchical clustering. In: Gaul, W., and Schader, M. (Eds.), Classification as a Tool of Research. Elsevier, North-Holland, Amsterdam, pp. 289–301; Thompson, Byron J., 1985. A flow rerouting algorithm for the maximum concurrent flow problem with variable capacities and demands, and its application to cluster analysis. Master Thesis. School of Engineering and Applied Science, Southern Methodist University] provide the basis for partitioning a social network by way of sparsest cuts and/or maximum concurrent flow.  相似文献   
75.
结合朔黄铁路DK262+000-DK265+000段的石方路堑工程的施工实例,详细介绍了深孔台阶微差爆破技术在铁路路堑石方施工中的应用,指出了施工中的难点和应用注意的问题。  相似文献   
76.
Environmental tobacco smoke (ETS) is a major contributor to indoor human exposures to fine particulate matter of 2.5 μm or smaller (PM2.5). The Stochastic Human Exposure and Dose Simulation for Particulate Matter (SHEDS‐PM) Model developed by the U.S. Environmental Protection Agency estimates distributions of outdoor and indoor PM2.5 exposure for a specified population based on ambient concentrations and indoor emissions sources. A critical assessment was conducted of the methodology and data used in SHEDS‐PM for estimation of indoor exposure to ETS. For the residential microenvironment, SHEDS uses a mass‐balance approach, which is comparable to best practices. The default inputs in SHEDS‐PM were reviewed and more recent and extensive data sources were identified. Sensitivity analysis was used to determine which inputs should be prioritized for updating. Data regarding the proportion of smokers and “other smokers” and cigarette emission rate were found to be important. SHEDS‐PM does not currently account for in‐vehicle ETS exposure; however, in‐vehicle ETS‐related PM2.5 levels can exceed those in residential microenvironments by a factor of 10 or more. Therefore, a mass‐balance‐based methodology for estimating in‐vehicle ETS PM2.5 concentration is evaluated. Recommendations are made regarding updating of input data and algorithms related to ETS exposure in the SHEDS‐PM model. Interindividual variability for ETS exposure was quantified. Geographic variability in ETS exposure was quantified based on the varying prevalence of smokers in five selected locations in the United States.  相似文献   
77.
文章以烟丝群为研究对象对其在水平管道的运动方程进行分析,推导出时间、空间模式下的无因次方程;在初始速度为零的条件下,摩擦系数越大,烟丝群最终稳定速度越小,加速时间和加速距离也越小,悬浮速度对烟丝群最终速度影响不大。结果对系统的优化和运行有指导意义。  相似文献   
78.
用烟草赤星病菌(Alternaria alternata)7个菌株测定的结果表明,病菌在各5种含量的干烟叶和鲜烟叶煎汁培养基(分别简称 DTLA 和 FDTLA)上较在 PDA 培养基上的生长能力差。病菌达到最大生长量时,DTLA 中干烟叶和 FDTLA 中鲜烟叶用量分别为30g/L 和30~50g/L,烟叶用量增加趋向于抑制病菌生长。产孢能力在烟叶煎汁培养基(TLA)上较在PDA 上为强,并随烟叶用量增加呈逐渐增强趋势,分别以烟叶用量60~90g/L(DTLA)和100~150g/L(FDTLA)为产孢饱和点。在 FDTLA 中加入蛋白胨能降低病菌的生长能力,但可增强产孢能力强的菌株的产孢量。  相似文献   
79.
ABSTRACT

Identifying with more than one ethnicity is becoming increasingly common in New Zealand. It is therefore important that the methods of categorising ethnicity used by government agencies and researchers effectively account for diverse ethnic identities. The aim of this research was to assess the impact of using different methods of categorising ethnicity on understanding outcomes in New Zealand, using Census 2013 information about tobacco smoking among the population aged 15+ years as an illustration. Prioritised, total response and single/combination categorisation methods were compared. Prioritised and total response categorisation generally produced similar prevalence estimates and patterns for smoking status, although estimates diverged somewhat for Māori ethnic groups and to a lesser extent for Pacific Peoples and Asian ethnic groups. Single/combination categorisation indicated that combination ethnic groups tend to have smoking outcomes between those of the constituent groups. Categorisation method had a considerable impact on the size of some ethnic groups. Prioritised ethnicity categorisation may be inappropriate for use by government agencies and for policy-relevant research principally concerned with children, young people, Māori or Pacific Peoples. Single/combination categorisation is useful for understanding the associations between ethnicity and outcomes, however previous work suggests this method should be used with caution.  相似文献   
80.
民间剪纸是中国平民百姓的市俗中手工的艺术,从形式上看,仅是将节令、居住、服饰、诞生、成 年、婚葬、寿筵在剪纸上的反映,但其中却包含着中华民族的优良传统和敦厚的文化底蕴、审美情操,值得 当代人去关注、研究和发扬。  相似文献   
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