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921.
"参"在传世文献中用作度量衡单位时多为重量单位,而秦汉简帛文献中则非如此,亦非指酒器"觯",而是用作容量单位,为"小斗"的"三分之一"。 相似文献
922.
AbstractThis study sought to determine if human papillomavirus (HPV) vaccination rates are associated with teaching requirements for abstinence in state sex education laws and policies. A cross-sectional analysis was conducted assessing the association between abstinence education legislation and HPV vaccination rates in adolescents (aged 13–17?years). After adjustment for insurance coverage and household income, the level of abstinence education was not significantly associated with vaccination rates. However, a higher percentage of individuals uninsured was significantly and negatively associated with the vaccination rate. This suggests that HPV vaccination rates are associated with insurance coverage, but not with the degree to which sex education laws or policies emphasize abstinence. 相似文献
923.
网络环境下师范院校教师的素质 总被引:1,自引:0,他引:1
在网络环境下,以计算机技术为基础的现代信息技术被广泛应用于教育教学中,教学模式发生根本性的变化,这就要求师范院校教师不断对自己的教育教学活动进行研究、反思,掌握在网络环境下新教学媒体的应用和操作技能,对自己的知识、经验与现代教育技术进行重组,才能不断适应新的变革。 相似文献
924.
A newly isolated strain EL31410, producing elastase (E. C3. 4. 4. 7) with high elastolytic activity was identified asBacillus sp. In the medium optimization, it was found that wheat bran and soybean flour hydrosate were the best crude carbon and nitrogen
source for enzyme production, respectively. Addition of corn steep flour can affect the bacterium growth and elastase production.
A fractional factorial design was applied to study the main factors that affect the enzyme production, and central composite
experimental design and response surface methodology were adopted to derive a statistical model for the effect of wheat bran
and soybean flour hydrosate on elastase production. The experimental results showed that wheat bran had positive effect but
soybean flour hydrosate had negative effect, on enzyme production. An initial concentration of 3.4% (w/v) wheat bran and 9.4%
(v/v) soybean flour hydrosate were found to be optimal for enzyme production in batch culture. The time course of elastase
production in the optimized medium composition was also described.
Project (No. 300024) supported by the Zhejiang Provincial Natural Science Foundation of China 相似文献
925.
926.
主要研究了汇川公司H2U可编程控制器(PLC)的通信技术,实现了两个H2U系列PLC之间基于RS-485的通信,并详细介绍了PLC之间通信的硬件连接方式、通信串口参数配置、触摸屏画面的设计以及程序实现。所讨论的方法已在采用H2U PLC及辅助设备组建的"运动控制系统"课程的教学实验平台上进行了验证,可以拓展应用于多台H2U PLC之间以及其他设备与H2U PLC之间的RS-485通信实现,对工程应用具有一定的借鉴意义。 相似文献
927.
文章首先介绍了国内外高校图书馆利用SNS的概况,然后总结了国内高校图书馆应用SNS的模式,最后对国内高校图书馆应用SNS的策略进行了分析. 相似文献
928.
Peter Hesseldenz 《Journal of Business & Finance Librarianship》2013,18(4):287-299
MBA program curriculums have been the target of criticism since the financial scandals of the early 2000s, with the main focus being that many programs sacrificed the teaching of useful, real world skills in favor of impractical scientific research, while also neglecting areas such as ethics and social responsibility. The financial collapse prompted many MBA programs to implement reforms which include adding experiential learning programs among other changes. These reforms provide opportunities for librarians to introduce or increase information literacy components in the programs. The current state of MBA information literacy practices is discussed, with several initiatives highlighted and some new approaches suggested. 相似文献
929.
分析了自适应匹配滤波器和向量自回归(VAR)时域白化滤波器. 结果表明,通过最小化用误差平方之和估计的均方误差得到的参量滤波器系数和通过相同阶数的多通道最小二乘法得到的VAR滤波器系数是等价的. 此外,还分析了VAR滤波器最小二乘估计器的渐进性能,分析了滤波器的运算量和杂波抑制性能. 相似文献
930.
As an attempt to seek more reliable and valid methodology to enhance traditional college reading classes in China,the paper aims to explore an instructional approach named Collaborative Strategic Reading(CSR) based on the analysis of current college reading instructions,the suitability of CSR applied in authentic teaching context as well as pedagogical recommendations attempted to present practicable concept for college reading instructions. 相似文献