英汉被动语态的对比分析

学习外语会受到本族语言的干扰和影响 ,但是如果能以科学的方法对两种语言的特征进行比较研究 ,分析其异同 ,说明其译法 ,就会将母语的干扰变成促进语言学习的有利因素 ,从而提高语言学习的能力。用对比语法学的研究方法 ,对英语和汉语的被动语态进行了概括地对比分析研究 ,使学生对英、汉语法的结构、用法及特征的异同有所了解 ,从而找到英语学习的有利途径 ,提高英语和汉语学习水平     

辩证认识和循序推进中国学前教育普惠化、免费化及义务化历史进程

目前,社会各界关于如何大力发展学前教育的代表性对策建议有三类：一是大力推进普惠性学前教育,二是大力推进免费性学前教育,三是大力推进义务性学前教育。陕西学前师范学院学报编辑部面向全国青年教师发起的“是否应将学前教育纳入义务教育体系：怎么看与怎么办”的通信笔谈提出了以下共识建议：目前我国不宜将学前教育纳入义务教育体系,大力推进普惠性学前教育是目前的务实定位选择,应积极创造条件并循序推进学前教育普惠化、免费化及义务化历史进程。     

美国高校汉语课程教学的特点和启示——以布里奇波特大学为例

位于美国康涅狄格州布里奇波特市的布里奇波特大学长期开设汉语选修课程,一直以来选修人数仅居于西班牙语之后,是学校中比较受欢迎的语言类选修课。笔者在旁听汉语课程的过程中深刻感受到美国大学生对汉语的学习热情以及华人教师独特生动的授课方法。本文将从生本观念、教学方式及文化传播等方面论述美国高校的汉语教学对我国地方性本科院校在汉语教学方面的借鉴和启示。     

透过货币起源和发展探讨货币的本质

本文通过分析货币的起源，认为货币有两条主要的发展路线，其一是由物物交换发展为利用一般等价物交换，一般等价物后固定为金银，然后发展出铸币；另一条路线是由生殖崇拜物贝壳发展到仿制贝壳，再到铸币。从这两种发展路线说明价值的两种来源：实用价值和精神价值；两种价值都产生了铸币。本文认为在历史上货币价值的产生早于信用的产生。由货币的发展过程说明本质上货币是价值和信用的复合体，起初人们看重的是价值，后来价值的成分逐渐减少而信用成分逐渐增加，最终发展成为纯信用货币。     

Sampling Strategies for Evaluating the Rate of Adventitious Transgene Presence in Non‐Genetically Modified Crop Fields

According to E.U. regulations, the maximum allowable rate of adventitious transgene presence in non‐genetically modified (GM) crops is 0.9%. We compared four sampling methods for the detection of transgenic material in agricultural non‐GM maize fields: random sampling, stratified sampling, random sampling + ratio reweighting, random sampling + regression reweighting. Random sampling involves simply sampling maize grains from different locations selected at random from the field concerned. The stratified and reweighting sampling methods make use of an auxiliary variable corresponding to the output of a gene‐flow model (a zero‐inflated Poisson model) simulating cross‐pollination as a function of wind speed, wind direction, and distance to the closest GM maize field. With the stratified sampling method, an auxiliary variable is used to define several strata with contrasting transgene presence rates, and grains are then sampled at random from each stratum. With the two methods involving reweighting, grains are first sampled at random from various locations within the field, and the observations are then reweighted according to the auxiliary variable. Data collected from three maize fields were used to compare the four sampling methods, and the results were used to determine the extent to which transgene presence rate estimation was improved by the use of stratified and reweighting sampling methods. We found that transgene rate estimates were more accurate and that substantially smaller samples could be used with sampling strategies based on an auxiliary variable derived from a gene‐flow model.     

三峡库区(湖北部分)重点保护野生脊椎动物研究

三峡库区 (湖北部分 )现有国家重点保护野生脊椎动物 5 9种 ,隶属于 4纲 11目 18科 41属。结合其分布特点 ,总结了蓄水后对这些保护动物的影响 ,并提出了保护措施     

Minimum Cost Edge Subset Covering Exactly k Vertices of a Graph

Given a graph G with nonnegative edge costs and an integer k, we consider the problem of finding an edge subset S of minimum total cost with respect to the constraint that S covers exactly k vertices of G. An O(n ³) algorithm is presented where n is the order of G. It is based on the author's previous paper dealing with a similar problem asking S to cover at least k vertices.     

幂群的正则表示

通过幂群在其自身的左平移作用 ,给出了有限群上幂群的正则表示 ,进而给出了幂群的正则矩阵表示。     

股票模拟实验系统的研究及应用

通过股票模拟实验，能使学生掌握股票投资的基本操作技能，能培养学生正确的投资意识和投资理念，为使学生走向社会投资理财奠定坚实的基础。     

模糊物元模型在生态林项目效益评价中的应用研究

在模糊物元分析原理的基础上,采用基于欧式贴近度的模糊物元模型评价生态林项目综合效益水平。根据生态林项目综合效益评价特点,提出综合效益评价指标体系,确定评价等级与单因素评价标准;将生态林项目综合效益的各个评价等级及待评价项目作为物元的事物,将各评价等级和待评价项目的评价指标及其模糊量值作为复合模糊物元,通过计算复合模糊物元与标准物元之间的欧式贴近度,分析待评价生态林项目综合效益水平。以昕水河流域生态防护林项目为例,计算表明该生态林项目综合效益处于良-中等级之间,其结果直观地衡量了该项目综合效益水平。