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971.
Sandrine Turcotte Thérèse Laferrière Christine Hamel Alain Breuleux 《Systemic Practice and Action Research》2010,23(4):285-299
Small remote rural schools in Quebec face an ongoing challenge to provide similar quality educational services than bigger
schools. Since 2002, the Remote Network Schools (RNS) initiative afforded schools the opportunity to reinvent their practice
by using online tools to experience collaborative learning activities with other remote schools. Teachers and students experienced
quality learning and demonstrated agency by implementing the RNS in their context. Measures include: diversity of learning
activities, quality of online classroom interactions, changes in teacher beliefs, and shifts in teacher and student roles.
Our results show that it is a viable operating method for such schools and that other schools could contemplate implementing
such innovative practices. 相似文献
972.
In this paper,we propose a new image denoising method that combines total variation(TV) method and wavelet shrinkage. In our method,a noisy image is decomposed into subbands of LL,LH,HL,and HH in wavelet domain. LL subband contains the low frequency coefficients along with less noise,which can be easily eliminated using TV-based method. More edges and other detailed information like textures are contained in the other three subbands,and we propose a shrinkage method based on the local variance to extract th... 相似文献
973.
The security issues of mobile agent system have embarrassed its widespread implementation. The paper analyses communication security threats and countermeasures of mobile agent system and proposes a communication security protocol of mobile agent system. It provides multifactor authentication, encryption transmission, and integrity protection of mobile agent. 相似文献
974.
<正> In this paper,an equivalency condition of nonsingularity in nonlinear semidefinite programming,which can be viewed as a generalization of the equivalency condition of nonsingularity for linearsemidefinite programming,is established under certain conditions of convexity. 相似文献
975.
张瑶 《黔西南民族师范高等专科学校学报》2014,(3):76-79
阅读课教学是高校英语专业教学体系中的重要组成部分,也是英语教学中的难点.当前英语阅读教学存在着教学理念陈旧、方法单一等问题,教师应与时俱进,积极创新以满足实际教学的需要和学生多样性的需要. 相似文献
976.
<正> A family of integral-type goodness-of-fit tests is investigated.This family includes someexisting tests,such as the Cramér-von Mises test and Anderson-Darling test,etc.The asymptoticdistributions of the tests in the family under the null and local alternative hypotheses are established.The almost sure convergence under a fixed underlying distribution is obtained.Furthermore,simulationsare conducted to compare the powers of the tests in the family.Simulation results show that fordifferent alternatives,the more powerful tests are different,and the parameter λ has great influence onthe tests in small sample cases. 相似文献
977.
Four divalent lanthanide complexes Sm(ArO)2 - (THF)4, Yb(ArO)2(THF)3, Eu(ArO)2(THF)3 (ArO = 2,6-di- tert-butyl-4-methylphenolate) and (ButCp)2Sm(THF)2 were synthesized. Their catalytic activities on the polymerization of acrylonitrile were studied. The catalytic activities were influenced by the central metal ions involved. The catalytic activities of these divalent lanthanide complexes can be greatly increased by adding NaOC6H2-2,6-But2-4-Me, NaOC6H4-4-But, or NaOC10H6-2-Me. The amount of additive has apparent effect on the catalytic activity, but the additive has no effect on the tacticity of the resulting polyacrylonitrile. 相似文献
978.
高校培养学生工程实践能力的途径 总被引:6,自引:0,他引:6
实践是高等工程教育的灵魂与根本。本文从强化学生实践意识、课程体系改革及师资队伍建设三个视角,针对如何有效提高学生的工程实践能力提出了一些举措与建议,以期为我国高等工程教育改革提供参考。 相似文献
979.
文章通过新型复合加筋带挡土墙在晋祠互通中的应用实例,对加筋材料选择和加筋挡土墙稳定进行了分析,并进一步完善新型复合加筋带挡土墙的施工工艺,为山西省新型复合加筋带挡土墙的推广,奠定了一定的基础. 相似文献
980.
本文首先简要介绍了后向传播人工神经网络的基本原理,然后用这种网络模拟了电磁波在粗糙面的散射。结果表明,用神经网络模拟电磁波在复杂环境中的传播是一种简单有效的方法。 相似文献