统计学方法在分析化学中的应用──用自助法估计样品平均数

以实例讨论了自助法的原理和方法,表明用该法在指导生产和科学试验方面可以节省时间和降低费用,是一个有推广价值的好方法。     

有害物品运输中的风险平衡性

在有害物品运输过程中，运输路径上的各个路段的风险具有很大的差异，而且某些路段被多次选择。为了平衡有害物品运输过程中的风险，给出了有害物品运输过程中区域风险差异和个体风险差异的定义，建立了区域风险差异和个体风险差异的模型。构建了一个考虑了人口风险、区域风险差异和个体风险差异的实现有害物品运输中风险平衡性的模型，给出了求解问题的启发式算法。     

人口目标控制仿真系统

本文建立一种网状递阶结构人口目标控制仿真系统,并设计了相应的递阶循环迭代算法。仿真试验结果给出导致人口目标实现的控制律,即年度生育计划,及政策制约下的各项人口指标。     

Trade-offs in model-building: A more target-oriented approach

In his 1966 paper “The Strategy of model-building in Population Biology”, Richard Levins argues that no single model in population biology can be maximally realistic, precise and general at the same time. This is because these desirable model properties trade-off against one another. Recently, philosophers have developed Levins’ claims, arguing that trade-offs between these desiderata are generated by practical limitations on scientists, or due to formal aspects of models and how they represent the world. However this project is not complete. The trade-offs discussed by Levins had a noticeable effect on modelling in population biology, but not on other sciences. This raises questions regarding why such a difference holds. I claim that in order to explain this finding, we must pay due attention to the properties of the systems, or targets modelled by the different branches of science.     

Unusual geographic pattern of interpopulation variation in a spring snail Bythinella (Gastropoda: Prosobranchia)

Allozyme polymorphism, mean gene diversity, and a variety of pairwise genetic distances, theta and Nm were analysed for 20 populations of the spring snail Bythinella from Central Europe. Pairwise Mahalanobis' distances for morphological characters and geographic distances were also computed. Contrary to prior assumptions, the level of polymorphism was considerable, and correlations were found to be statistically significant between the genetic and geographic distances, as well as between Mahalanobis' and geographic distances. The present high level of isolation of local populations of the previously amphibious and continuously distributed snail is postulated to be due to a shift in climate and in the snail's habitat preference.     

Population dynamics of the bark-dwelling spider Eustala perfida Mello-Leitão, 1947 (Araneidae)

Population dynamics of spiders may vary according to biotic and abiotic factors. We studied the phenology of the bark-dwelling spider Eustala perfida over a two-year period and investigated how temperature, precipitation, and prey availability were associated with the population of this species. The population of E. perfida presented a well-defined fluctuation, with one reproductive cycle per year. The recruitment of spiders occurred in summer, followed by successive phenological peaks at all stages of development. The species is protogynic, and the population of adult males peaks in the cold/dry season, indicating a winter mature phenological pattern. The diet of E. perfida is composed mainly of medium-sized homopterans, complemented by small dipterans and hymenopterans. We found that the higher abundance of spiders occurred two months after the highest values of precipitation and temperature, and three months after the higher abundance of potential prey items. These results indicate that spiders require time to respond to changes in environmental conditions. The species’ natural history and the structure of the trunks in which it lives may also affect the number of individuals in a particular area and over time.     

论邓小平人口思想的特点

邓小平人口思想十分丰富,具有显著的特点。邓小平同志坚持一切从实际出发,立足中国现实,运用辨证思维,从战略高度实事求是地认识、分析我国人口问题,把人口多作为我国最重要的国情,特别是他把人口问题放在国民经济发展的全局中来考察、处理,首次提出“人均”概念,是其人口思想中最具特色的内容。弄清邓小平人口思想的特点,对我国人口与计划生育实践有重大指导作用。     

考虑年龄结构的女性模型

本文提出一种考虑年龄结构的离散人口模型,并进一步讨论这种模型的性质及其应用。     

桂西壮族入赘婚俗探因

从招赘、入赘的动机和为何能够长期延续的角度分析入赘婚流行的原因是有价值的,可是不能从根本上揭示形成入赘婚俗的真正原因。其实桂西壮族流行入赘婚俗的主要原因有四：地旷人稀、人口密度小,血缘组织不严密,女多男少的性别比,男女关系的平等无嫌。其中的人口密度和血缘组织关系两个原因是桂西壮族入赘婚俗流行的最关键的起决定作用的要素。     

达乌尔黄鼠的年龄鉴定与种群年龄分析

本文从所获的达乌尔黄鼠样本中随机抽出153只,其中雄鼠70只,雌鼠83只,以晶体干重为依据可分为3个年龄组,并与臼齿磨损程度,体长、体重等指标作相关分析,有助于了解泰来县鼠疫疫源地区达乌尔黄鼠的种群结构.