施用NPK肥对高梁杂交草吸收Cu的影响     

邢素芝  汪建飞  王少梅 《安徽科技学院学报》2003,17(4):313-315

采用盆栽试验,研究了施用NPK肥料对高粱杂交草吸收微量营养元素Cu的影响.结果表明,各处理Cu的吸收量大小的顺序依次为NPK＞NP＞NK＞N＞P＞K＞CK＞PK;各处理高粱杂交草体内Cu浓度的变幅是24.7～39.8μg/g;N是影响高粱杂交草吸收Cu的主导因子,由于稀释效应,施N处理的高粱杂交草体内Cu的浓度相对较低.  相似文献   

基于安卓系统的均衡器算法的仿真及应用          下载免费PDF全文

林金阳庄伟达 《福建工程学院学报》2020,(6):583-586

针对安卓系统原生Audio Effect 框架不支持32 bit 音频的问题,提出了采用FFmpeg 开源音视频框架自定义新的Audio Effect 框架。选用高阶音频参数多波段均衡器算法的巴特沃斯部分作为滤波,对该算法进行分析、验证和应用测试。仿真和测试结果显示,该方法可以提高均衡准确性,达到设计要求。  相似文献   

Sandcastle competitions     

Jon Baggaley 《Distance Education》2016,37(3):366-375

This commentary discusses reasons that lead scholars to feel entitled to make judgements in areas where they have little or no expertise. Three current reports about the future of online learning are considered, issued by the Global Learning Council, Massachusetts Institute of Technology, and the Gates Foundation. Two of these publications contain contradictions and confusion that may simply be due to lack of awareness of distance education (DE) and online learning research. The third report gives good evidence but has been criticized for being too academic. The conflicting standards and criteria evident in such writings may be due to institutional pressures to promote policies and principles despite lack of supportive evidence, and to weaknesses in the DE literature itself. As major institutional policies about online learning are likely to be based on the recommendations of such reports, it is important for DE specialists to challenge them where appropriate.  相似文献   

Separating arguments from conclusions: the mistaken role of effect size in educational policy research     

Adrian Simpson 《Educational Research and Evaluation》2019,25(1-2):99-109

ABSTRACT

Effect size is the basis of much evidence-based education policymaking. In particular, it is assumed to measure the educational effectiveness of interventions. Policy is being driven by the influential work of John Hattie, the Education Endowment Foundation, and others, which is grounded in this assumption. This article demonstrates the assumption is false and notes that, when criticized, proponents either attempt to inoculate themselves by listing (without checking) assumptions or use the specious reasoning that, however flawed their argument, no-one has disproved their conclusions.  相似文献   

在大学中实行多媒体教学的探讨   总被引：5，自引：0，他引：5  

陈前火  叶瑞洪  吴玉珍 《福建师大福清分校学报》2005,(2):46-49

对多媒体教学方式在大学教学应用中的现状进行了调查，调查结果表明92％的学生认为传统教学方式与多媒体教学相结合的方式是最好的教学方式，同时阐述学生对这种教学方式的态度，并对在多媒体教学效果方面存在的问题加以剖析，并提出具体的教学建议。  相似文献   

偏爱“差生”辩     

彭萍 《零陵学院学报》2002,(2)

在全面推进素质教育的过程中,偏爱“差生”是一种全新的教育观念,一、偏爱“差生”能够产生最佳心理效应,符合素质教育的要求;二、偏爱“差生”符合因材施教的原则,是一种更高的教育教学艺术,不会产生负效应;三、人生需要赞美,绝大多数“差生”是可以转变的。  相似文献   

农民素质对农业经济增长和可持续发展的影响     

王洁莉 《平原大学学报》2004,21(4):40-42

提高农民的素质是解决农业问题的重要措施之一。目前农民素质的现状对农业经济增长和可持续发展有重要的影响。  相似文献   

词语变用浅说     

常奇 《绥化学院学报》2002,22(2):56-58

本文讨论了词语变用的必然性，表达效果，主要方式，及应注意的问题。  相似文献   

Exploring the Roles of Social Presence and Gender Difference in Online Learning     

ChongWoo Park  Dong‐gook Kim 《Decision Sciences Journal of Innovative Education》2020,18(2):291-312

Online learning has become more popular in higher education with its advantages of flexibility and accessibility. However, there have been challenges to students’ learning experience in online learning. One critical challenge would be providing interactions between students and instructors as good or effective as in the face‐to‐face environment. However, providing face‐to‐face interactions in online learning is not feasible because students and instructors are not physically present together. In this study, we introduce and empirically investigate social presence as student learning experience in online learning in which physical presence does not exist. Drawing upon the social presence and online learning literature, we propose a research model to explore how the interactivity of communication tools can drive social presence and student satisfaction in online learning. Furthermore, this study examines gender difference as a moderator in the model. Data were collected from undergraduate students who were taking online business statistics courses where an interactive communication tool was required to use for class communication and collaboration. The results showed that social presence driven by tool interactivity had a significant impact on student satisfaction in online learning. We also found that gender difference moderated the relationship between tool interactivity and social presence in online learning.  相似文献   

压电超声马达     

罗凤玲 《雁北师范学院学报》1995,(3)

本文介绍几种典型的压电超声马达的结构和运行原理,并简要说明国内外研究的进展情况。  相似文献