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关键词： 没食子   红外指纹图谱   二阶导数红外光谱   正态分布分析   聚类分析   主成分分析   正交偏最小二乘法-判别分析  

摘要： 目的:建立了不同批次的没食子药材红外光谱、二阶导数红外光谱,结合多元统计分析对25批没食子进行了研究,为没食子药材鉴别提供新的方法。方法:采用傅里叶变换红外光谱仪采集不同批次没食子药材红外光谱,利用OMNIC软件对25批没食子药材样品的红外指纹图谱进行基线校正、平滑等处理,采用Microsoft Excel2016进行正态分布分析,采用SPSS 22.0软件进行聚类分析和主成分分析,采用SIMCA 14.1软件进行正交偏最小二乘法-判别分析,以变量重要性投影(VIP)值>1为标准,筛选影响没食子药材成分质量的标志性波数。结果:对25批没食子药材样品进行了红外光谱分析,其相关系数为0.932 7~0.995 6。二阶导数图谱可以分离出原光谱中的一些相互重叠的吸收峰。正态分布曲线结果表明,广西来源与安徽来源没食子药材质量存在明显差异,中国广西、广东与伊朗哈吉阿巴德来源没食子药材样品质量相近。聚类分析表明,25批没食子药材在10~15个组间的间距下可以聚成4类。主成分分析发现,累积方差贡献率为89.565%;广西来源没食子药材的综合得分最高,安徽来源没食子药材的综合得分最低。正交偏最小二乘法-判别分析表明,25批没食子药材样品可很好地聚为4类;共筛选出5个影响没食子药材质量的关键波数。结论:不同来源的没食子样品的红外特征从峰形与峰高都存在着一定的差异性,采用红外光谱、二阶导数图谱可以初步鉴别没食子药材,与正态分布分析、聚类分析、主成分分析及正交最小二乘法-判别分析相结合,可丰富其鉴别信息,为进一步鉴定没食子药材提供参考。

关键词： 课赛融合   统计学   酒店管理专业  

摘要： 统计学是管理类专业的基础课程,是专业处理数据的综合性学科,课程培养学生利用数据分析工具和方法进行决策的能力,具有综合性和应用性。近年来,“课赛融合”教学模式成为高校课程教学改革的趋势和学者研究的热点,在“课赛融合”背景下,统计学课程应优化课程内容,创新教学方法,积极探索提升学生统计分析实践能力的教学方式。文章针对酒店管理专业学生培养目标,构建“课赛融合”背景下统计学课程教学模式,探索课程改革实施方案,对统计学课程教学改革提出有效的措施与建议,实现学生数据管理思维培养目标。

关键词： Geostatistics   Groundwater flow   Transmissivity   Lithofacies   Universal kriging  

摘要： Transmissivity is a significant hydrogeological parameter that affects the reliability of groundwater flow and transport models. This study demonstrates the improvement in the estimated transmissivity field of an unconfined detritic aquifer that can be obtained by using geostatistical methods to combine three types of data: hard transmissivity data obtained from pumping tests, soft transmissivity data obtained from lithological information from boreholes, and water head data. The piezometric data can be related to transmissivity by solving the hydrogeology inverse problem, i.e., including the observed water head to determine the unknown model parameters (log transmissivities). The geostatistical combination of all the available information is achieved by using three different geostatistical methodologies: ordinary kriging, ordinary co-kriging and inverse problem universal co-kriging. In addition, there are eight methodological cases to be compared according to which log-transmissivity data are considered as the primary variable in co-kriging and whether two or three variables are used in inverse-problem universal co-kriging. The results are validated by using the performance statistics of the direct modelling of the unconfined groundwater flow and comparing observed water heads with the modelled ones. Although the results show that the two sets of log-transmissivity data are incompatible, the set of log-transmissivity data from the lithofacies provides a good log-transmissivity image that can be improved by inverse modelling. The map provided by inverse-problem universal co-kriging provides the best results. Using three variables, rather than two in the inverse problem, gives worse results because of the incompatibility of the log-transmissivity data sets.

关键词： Geostatistics   Voronoi tessellation   Groundwater monitoring   Nitrate   EU Water Framework Directive  

摘要： Monitoring and assessing groundwater quality according to European directives and national regulations is usually based on interpolation techniques, e.g. Kriging. However, contour maps of hydrochemical parameters often suggest a spurious local accuracy and can therefore lead to inappropriate action measures. Here, the early concept of extension variance combined with the Voronoi tessellation regionalization is proposed. The mosaic-like representation of pollutant concentrations in Voronoi polygons avoids misinterpretations caused by interpolation. The additional calculation of the extension variance, which is based on fundamental geostatistical assumptions, allows for estimating the probability that a given threshold is exceeded. This concept is further extended to hydraulically delimitable groundwater bodies, thus ensuring that hydraulic boundaries are considered. A method is here described for the assessment of groundwater quality with respect to nitrate concentration in the principal aquifer of the state Mecklenburg-Western Pomerania in Germany.

关键词： Geostatistics   Non-aqueous phase liquids (NAPLs)   Deep learning-based inversion   Data assimilation   Highly correlated parameters inversion  

摘要： High-resolution site characterization of hydraulic properties and source zone architecture (SZA) are essential for performing risk assessment and designing remediation strategies for dense nonaqueous phase liquid (DNAPL) contamination. DNAPL SZA characterization is challenging because of the highly correlated unknown states and parameters, namely the spatial distribution of DNAPL saturation (S-N) and hydraulic conductivity (K). Two methods can be used for the inversion of highly correlated parameters, i.e., geostatistical inversion with and without parameter-state cross-correlation. In this study, numerical experiments considering weak and strong heterogeneity for S-N and K are used to compare the performance of the two geostatistical inversion methods and the deep-learning-based correlation method. Results show that the inversion with combined parameter-state cross-correlation successfully estimated both the K and DNAPL SZA for a weakly heterogeneous K field, but fails to reproduce the overall morphology of the DNAPL SZA for a strongly heterogeneous K field. In comparison, the inversion without parameter-state cross-correlation can robustly capture but over-smooth the detailed features of the K and DNAPL SZA, due to the deviation of the highly correlated K-S-N fields from the simplified prior cross-covariance. The deep-learning-based method consistently outperformed the inversion strategies with and without the parameter-state cross-correlation, in terms of computational efficiency and estimation accuracy for both the simple and the complex DNAPL SZA, since it can implicitly capture the K-S-N interdependence and the physical patterns of the DNAPL SZA without explicitly coupling the multiphase model to account for the K-S-N correlation.

关键词： 应急物流   物资分配   不公平厌恶  

摘要： 在灾害发生后，应急物资的分配是否公平，是灾民们关注的重点之一。公平的应急物资分配既有利于安抚灾民的情绪，稳定灾区的社会秩序，也有利于应急资源的合理与充分利用，避免造成浪费。然而，公平的分配并非简单地按照数量平均分配，而是需要根据灾民的具体情况，进行“按需分配”。为了更好地考虑灾民的需求与公平感知，真正做到“以人为本”，本文提出采用不公平厌恶作为衡量应急物资分配公平性的指标。不公平厌恶是一个被广泛地应用于经济学、社会心理学的概念，主要衡量了人们对于不公平分配的厌恶程度，在一定程度上可以从受益人本身而非决策者的角度衡量物资分配的公平性，避免了决策与实际相脱节的尴尬情况。本文研究应急情境下灾民公平感知影响因素问题，通过使用福利经济学受偿意愿方法设计调研问卷收取研究数据。研究结果表明：（1）应急物资分配的数量差异、灾民的性别、受教育程度与年龄对灾民不公平厌恶程度存在显著影响；（2）当应急物资分配的数量差异较小的时候，人口统计学因素（灾民的性别、收入、年龄以及受教育程度）对于灾民不公平厌恶的影响不显著，但随着差异变大，影响会变得显著。据此本文为应急物流决策者进行应急物资的分配提供了建议，有助于减轻灾民负面情绪对应急物流行动的影响。

关键词： 检验值   核心影响因子   中国科技期刊引证报告   不等式   学术水平   显著提高  

摘要： 为提高论文的科学性和准确性,我刊自2014年第一期起改进论文统计学处理。要求:提供具体P值,不是不等式的P<0.05等,其前要配有检验值(t,χ^(2)等)。从而显著提高了我刊的学术水平,使2021年发表的中国科技期刊引证报告达到核心影响因子0.645,扩展影响因子2.424。

关键词： 统计学   文献计量   知识图谱   研究热点  

摘要： 本文以四本CSSCI统计学期刊载文为研究对象,运用文献计量学方法分别对四本期刊2010-2021年载文数量、文章篇幅、基金资助、载文作者、发文机构进行了分析,借助可视化的知识图谱展现了发文机构合作情况,在对高被引、高下载文章及期刊全部载文关键词进行整理的基础上,对统计学研究热点进行了总结。研究发现,学者之间利用各自专业优势开展合作研究的趋势愈加明显,统计领域的学术交流程度和范围在不断扩展;统计学领域研究热点主要集中在国家发展战略和政策、经济发展质量和效益、统计学与其他学科的交叉研究成果和应用、统计理论方法的基础研究等方面。以上结论体现出统计核心学术期刊在人才培育、成果传播、学科发展方面起到重要的推动作用。

关键词： 标目   内容重复   自明性   主谓语   插图   统计学  

摘要： 表应具有自明性。表的内容不要与正文文字及插图内容重复。表应按统计学的制表原则设计,力求结构简洁。横、纵标目间应有逻辑上的主谓语关系,主语一般置表的左侧,谓语一般置表的右侧。

关键词： 辛普森悖论   田忌赛马   战国时期   齐威王   统计学   比赛  

摘要： 田忌赛马是一个家喻户晓的故事,说的是战国时期齐国大将田忌经常与齐威王赌注赛马,三局两胜制。由于田忌的马不如齐威王的马好,所以总是输掉比赛,郁闷异常。在一次比赛中,田忌按照军师孙膑事先出的主意,让他的下等马对齐威王的上等马,先输掉第一局;第二、三局比赛中,田忌的上等马对齐威王的中等马,中等马对齐威王的下等马,连赢两局,最终获得比赛胜利。田忌赛马的故事其实暗含着一个统计学的原理,这就是“辛普森悖论”。