论历史逻辑

历史逻辑是以历史时间的历时性和共时性统一为基础的概念推论,研究关于叙述史中基本概念之间的意义关系和推论规则。过去、现在和未来是历史逻辑的基本范畴,“过去-现在-未来”三段式是历史逻辑的基本公式,它是概念逻辑推论三段式“正题-反题-合题”在历史逻辑中的具体形式。历史逻辑研究的目的,是根据特定历史时段的特殊性,建构以不同时段概念为逻辑变项的历史逻辑,预见未来的发展,规划现在的实践。     

On uniform convergence of undiscounted optimal programs in the Mitra–Wan forestry model: The strictly concave case

In this paper, we show that the 1986 Mitra–Wan result establishing asymptotic convergence of maximal programs to the unique golden-rule forest in the case of undiscounted, strictly concave felicity functions can be strengthened, in the same setting, to the  uniform  asymptotic convergence of  optimal  programs to the unique golden-rule forest. We work with a notationally reformulated version of the model that may have independent interest.     

污水管段设计流量的图论解析

针对污水管段设计流量计算中较易出现理解偏差与计算错误的问题,引入图论的方法,用节点与管段的关联关系对污水管道节点流量和管段流量进行定义并求解,明确了相关物理概念的界限,能使计算思路清晰,便于理解记忆。     

苦荞风味糕生产工艺研究

以苦荞粉为主要原料、辅以面粉,采用三熟处理苦荞,生产新型苦荞风味糕,优化配方为:特一粉∶苦荞粉6∶4,蔗糖50%,复合疏松剂0.5%,调和油10%,谷氨酸钠0.02%,NaCl 0.8%,活性酵母0.5%;最佳生产工艺为:苦荞籽80℃干燥3~5 h后炒制25 min,磨粉并过80目筛,75~80℃热烫20 min,加辅料并和面后,30℃发酵3 h,制坯成型后蒸30 min,所得苦荞风味糕细腻柔和、风味俱佳。     

安徽省耕地保护前景分析

随着社会经济的发展，安徽省耕地供需矛盾日益突出，科学地分析安徽省耕地保护前景，探寻合理的耕地保护对策．具有重要的现实意义。本文立足于安徽省耕地资源现状，从粮食生产、非农建设占地两方面探讨安徽经济发展对耕地的需求前景，并采用灰色系统模型对耕地的供给变化进行预测，通过耕地供需形势的分析，针对性地提出保护耕地的相应对策。     

Hypothesis testing and parameter estimation based onM-statistics ink samples with unequal variances

Summary Ink samples with unequal variances,M-tests for homogeneity ofk location parameters are proposed. The asymptoticχ ²-distributions of the test statistics and the robustness of the tests are investigated. NextM-estimators (ME’s) of parameters are discussed. Furthermore positive-part shrinkage versions (PSME’s) of theM-estimators for the location parameters are considered along with modified James-Stein estimation rule. In asymptotic distributional risks based on a special feasible loss, it is shown that the PSME’s dominate the ME’s, and preliminary test and shrinkageM-versions fork≧4.     

Insurance premiums under demand constraints

Abstract

An alternative approach to the variance principle of premium determination is explored. The approach rationalises the principle in terms of an economic theory and formalises the notion that loadings in addition to the ‘fair’ premium are related to competition and expenses.     

The density of the time to ruin for a Sparre Andersen process with Erlang arrivals and exponential claims

We derive expressions for the density of the time to ruin given that ruin occurs in a Sparre Andersen model in which individual claim amounts are exponentially distributed and inter-arrival times are distributed as Erlang(n,?β). We provide numerical illustrations of finite time ruin probabilities, as well as illustrating features of the density functions.     

桑叶配方颗粒物质基准研究

桑叶配方颗粒迄今尚没有统一的质量标准。为提升桑叶配方颗粒的内在质量,对其物质基准评价方法进行了研究。选取具有代表性产地的15批桑叶制备物质基准,采用高效液相色谱法,以芦丁、异槲皮苷、紫云英苷作为评价指标,确定桑叶物质基准的出膏率范围、标志性成分含量及转移率范围,采用超高效液相色谱法,建立物质基准UPLC特征图谱,并对其主要成分进行指认。结果表明:15批物质基准中,芦丁转移率为19.94%～34.05%,异槲皮苷转移率为11.67%～43.58%,紫云英苷转移率为10.73%～43.05%;物质基准特征图谱中,标定了14个共有峰,指认出7个色谱峰,分别为新绿原酸、绿原酸、咖啡酸、芦丁、异槲皮苷、槲皮素-3-O-(6″-O-丙二酰基)-β-D-葡萄糖苷、紫云英苷。所建立的基准评价方法为桑叶配方颗粒质量标准的制定及其后续大规模生产提供了数据基础。     

长历时暴雨强度公式的推求方法

近年来,随着极端暴雨事件的出现,导致城市内涝灾害频繁发生,原有降雨历时仅为2h的市政排水设计暴雨强度公式已无法满足城市暴雨设计的需求,因此就要延长暴雨采样历时,推求出长历时(24h)暴雨强度公式。针对以上问题,根据北京市提供的52a(1961-2012)原始降雨资料并进行数字化处理,结合水利的长历时特点,采用兼顾市政排水,水利排涝,内涝防治的采样方法,应用P-Ⅲ分布曲线进行频率分析后采用6种经典方法推求暴雨强度公式的参数值,优选出误差最小且满足规范要求的暴雨强度公式参数值,进而推求长历时暴雨强度公式,在此基础上与短历时暴雨强度公式比较,分析两者的差异,为城市雨水排除规划设计提供科学依据和参考。