中子测厚的研究     

卢道明 《宁德师专学报(自然科学版)》1996,(2)

本文报告了利用慢中子透射法测量钢板厚度的研究结果．  相似文献   

Differences in Graduation Rates Between Young Black and White College Students: Effect of Entry into Parenthood and Historically Black Universities     

Amy?E.?SibulkinEmail author  J.S.?Butler 《Research in higher education》2005,46(3):327-348

Black and White students who enrolled in college by age 20 were selected from a national probability sample, in order to estimate the prevalence of having children and the effect of having a child on probability of graduation with a bachelors degree. Black students reported significantly higher rates of having children than White students, but rates for Black students at historically Black universities were similar to those of Black students at predominantly White universities. After controlling for family background, achievement, and other student characteristics, having a child within 5 years of starting college generally reduced the probability of graduating with a bachelors degree for Black women and White women and men. The independent effect of attending a historically Black college was significantly positive for Black women but not statistically significant for Black men.  相似文献   

“Hispanic” children: Theoretical,empirical, and related policy issues     

Eugene E. Garcia 《Educational Psychology Review》1992,4(1):69-93

Not only are school-age ethnic and racial minority children one of the fastest growing segments of the U.S. population, they are also one of the most vulnerable. Hispanic children in particular are representative of the at-risk status of minority populations, displaying a portrait of unrealized social, educational, and employment success. This paper addresses the background and history of U.S. social and educational policies as they relate to the Hispanic student. Recent empirical findings are presented which support the following: (a) the bilingual character of Hispanic children is not a linguistic, cognitive, or educational liability and, in fact, should be employed to promote academic achievement; (b) the culture of the Hispanic family and child are better understood with regard to socialization variables and the potential differences they produce when directly compared to Anglo culture; and (c) educational strategies for Hispanic students that respect and integrate students' social, psychological, and linguistic attributes serve students effectively.  相似文献   

加入WTO与西部地方政府管理职能的转变     

王吉平 《陕西理工学院学报(社会科学版)》2001,19(4):62-67

中国加入WTO，受影响最大的是政府，受冲击最大的是西部地区，西部地方政府转变管理职能成为当务之急，加入WTO要求政府依法行政、公正行政、推动市场开放、充分运用权利、具备较强管理能力。适应加入WTO后新形势，西部地方政府应完善宏观调控职能，加强市场监管职能，改进国有资产管理职能，健全公共服务职能，开拓扶持产业发展和企业提高国际竞争力的职能。  相似文献   

假设、推测和征询“VP0呢？”     

李晟宇 《内蒙古师范大学学报(哲学社会科学版)》2004,33(1):88-92

“VP0呢?”有多种语义类别,这些类别能够概括为带有形式标记的各种句法格式,假设、推测、征询“VP0呢?”疑问句是这些类别中的重点。假设和推测“VP0呢?”的形式和意义都有较大差异,征询“VP0呢?”形式趋于固定。深入分析这些格式是研究“VP0呢?”疑问句的重点。  相似文献   

基于BOPPPS教学模型的数学实践课堂教学     

杨昔阳  姚承佳 《教育教学论坛》2019,(7):201-202

BOPPPS教学模型强调师生互动,实现从已知到未知的自然过渡。数学实践是培养数学素养的有效方式。为了有效提高本科高校数学实践环节的课堂教学,本文以《数学实验》课程中的优化调度模型为例,结合作者的教学经验,讨论BOPPPS模型的有效课堂教学设计。  相似文献   

Open Queueing Network Model of Shanghai Public Transportation ProblemPeng     

Jianping 《上海大学学报(英文版)》1998,(2)

１ＩｎｔｒｏｄｕｃｔｉｏｎＢｅｃａｕｓｅｏｆｔｈｅｆａｓｔｄｅｖｅｌｏｐｍｅｎｔｏｆｅｃｏｎｏｍｙ,ｃｉｔｉｅｓａｒｅｂｅｃｏｍｉｎｇｌａｒｇｅｒａｎｄｌａｒｇｅｒ．Ｔｈｅｔｒａｆｉｃ,ｅｓｐｅｃｉａｌｙｔｈｅｐｕｂｌｉｃｔｒａｎｓｐｏｒｔａｔｉｏｎ...  相似文献   

A comparative study of Canadian and Taiwanese grade 5 children’s environmental behaviors,attitudes, concerns,emotional dispositions,and knowledge     

Hsin-Ping Huang  Larry D. Yore 《International Journal of Science and Mathematics Education》2005,1(4):419-448

  相似文献   

对主从触发器工作原理的进一步探讨     

邹华  赵光胜 《潍坊教育学院学报》2003,16(1):26-26,29

触发器是有记忆功能的电路,若在工作过程中电路内部出现噪声信号,给电路的工作带来不可知因素,将无法预知电路的工作结果,对工作非常不利,而主从触发器由于本身结构所决定,若控制不好CP=1期间的输入信号,很容易出现这种问题。本文分析了可能出现上述现象的几种情况,以便在工作中有目的地加以避免。  相似文献   

汉江上游流域蒸散量计算方法的比较及改进   总被引：12，自引：1，他引：12  

张东  张万昌  徐全芝 《资源科学》2005,27(1):97-103

利用汉江上游流域13个气象站的气象观测数据,对SWAT2000模型内嵌的3种潜在蒸散量计算方法:①Penman-Monteith(PM)法、②Pristley-Tayler(PT)法和③Hargreaves法以及FAO Penman-Monteith(FAO PM)法、DeBruin法进行了蒸散量(ET0)计算方法的分析和评价.以气象站实测小型蒸发数据经过折算得到的陆面潜在蒸散量为标准,对模拟蒸散量结果进行检验,根据相关系数、解释方差、确定性系数以及相关曲线斜率等4个指标的比较,详细讨论了各方法的适用性及模拟精度,认为5种方法中PM法和FAO PM法模拟精度最高.但是进一步分析发现FAO PM法存在部分中间气象参量计算错误以及存在与实测数据偏差较大的情况,会影响到水文过程中其它子过程的模拟.因此选择PM法作为汉江上游流域蒸散量计算的首选方法,并通过数据分析提出利用高程对模拟结果进行修正,提高了蒸散量模拟的精度.  相似文献