System competence modelling: Theoretical foundation and empirical validation of a model involving natural,social and human‐environment systems          下载免费PDF全文

Rainer Mehren  Armin Rempfler  Janine Buchholz  Johannes Hartig  Eva M. Ulrich‐Riedhammer 《科学教学研究杂志》2018,55(5):685-711

Constituting a metacognitive strategy, system competence or systems thinking can only assume its assigned key function as a basic concept for the school subject of geography in Germany after a theoretical and empirical foundation has been established. A measurement instrument is required which is suitable both for supporting students and for the evaluation of methodical‐didactic measures. Such a tool is theoretically anchored in an empirically validated geography‐didactic and cognition‐psychological competence model, providing a differentiated representation of both the internal structure of a competency and the proficiency levels. The starting point of this foundation was the development of a normative‐theoretically derived model of geographic system competence. Its empirical validation was performed in different phases aimed at operationalising the competence model by means of test problems. In order to analyse the factor structure of the theoretical model, various item response models were estimated. The item levels of difficulty expected in the competence model were related to the empirical levels of difficulty and predicted by means of ordinary least squares regression to verify the model for proficiency levels. The two‐dimensional competence model – with the two dimensions ‘system organisation and behaviour’ and ‘system‐adequate intention to act’ – exhibits a better fit in reference to the model fit criteria than the one‐dimensional and three‐dimensional models. The correlations between the expected and empirical item difficulties are positive. Items that should be more difficult according to the competence model are actually shown to be more difficult. These findings suggest the reliability and validity of this new measurement instrument for diagnosing and promoting geographical system competence. It has to be implemented in practice as the next step.  相似文献   

具分布时滞的HIV感染模型稳定性分析     

李国强  朱惠延 《娄底师专学报》2011,(2):74-78,90

通过讨论一类含CTL免疫应答的具分布时滞的HIV感染模型,分析了在分布时滞情况下未感染平衡点及感染无免疫平衡点的全局渐近稳定性,并给出了感染免疫平衡点局部渐近稳定的充分条件。  相似文献   

响应面法优化软包装风味鱼的加工工艺     

刘晶晶  陈春明  王雪锋  韩曜平  戴阳军 《常熟理工学院学报》2011,25(2):78-84

采用响应面法优化了风味鱼的加工工艺参数.通过对盐渍时间、盐渍浓度、卤制时间以及杀菌温度和时间的研究,确定风味鱼块的加工方法为：新鲜鱼切块后,采用4%的食盐在常压下盐渍3.8h或真空下盐渍100min,清洗沥干,再用一定比例的调味液卤制89min,沥干后送入鼓风干燥箱中进行阶段干燥（温度为30℃,干燥30min,升温至50℃干燥30min,最后升至100℃干燥2h）,取出冷却后进行真空包装,在115℃-118℃的条件下杀菌20min,得到的软包装风味鱼具有外观好、香味浓郁、耐咀嚼等特点.  相似文献   

福建省游泳场馆游泳者风险管理问题研究     

寇健忠 《洛阳师范学院学报》2011,30(11):113-116

结合福建省游泳场馆游泳者现状,采用多种方法游泳者风险及游泳场馆溺死问题进行研究,旨在建立游泳场馆安全管理体系.研究结果表明,游泳场馆游泳者风险源包括23个风险因素,福建省游泳场馆游泳者面临12个主要风险因素,游泳场馆可以采用风险避免、风险控制、风险转移和风险自留四种方法应对游泳者风险.  相似文献   

维生素C和免疫多糖对中华倒刺鲃非特异性免疫功能的影响     

谢嘉华  陈慧玲  袁建军 《泉州师范学院学报》2011,29(6):16-19

在中华倒刺鲃每千克基础饲料中分别添加免疫多糖2g、免疫多糖4g、维生素C（VC）700mg、VC1400nag、VC700mg＋免疫多糖2g、VC700mg＋免疫多糖4g、VC1400mg＋免疫多糖2g、VC1400mg＋免疫多糖4g,以基础饲料为对照组,连续投喂2周后,通过测定血液白细胞的数量,白细胞吞噬能力,血清、头肾和脾脏的溶菌酶活力,探讨不同浓度的免疫多糖和VC对中华倒刺鲃非特异性免疫功能的影响．结果表明：VC和免疫多糖都能提高中华倒刺鲃免疫机能,且免疫多糖和VC二者间在较低浓度组合时有协同作用,高浓度组合时反而产生拮抗作用．免疫多糖和VC的最适宜组合浓度为（VC700mg＋免疫多糖2g）／kg基础饲料．  相似文献   

SQL临时表在科研管理系统数据处理中的应用     

胡配祥  张成叔  陈良敏 《洛阳工业高等专科学校学报》2011,21(2)

临时表是tempdb数据库中的一种特殊数据库表,它用来暂存中间结果数据。在数据库应系统中,有效地利用临时表可减少系统开销和提高系统的运行速度,实现特殊功能。文中结合科研管理系统中临时表的几种使用方法,阐述了它在系统开发中的巧妙作用。  相似文献   

网络舆情中的政府回应策略分析     

李韦 《连云港职业技术学院学报》2011,24(3):39-43

网络舆情是现实民意在网络空间的反映,政府对网络民意的反应事关政府的执政基础和执政能力。文章根据2009年地方政府应对网络舆情能力排行榜的数据,归纳并分析排名高低的原因,总结出一些规律性的经验教训,为政府应对网络舆情提供有效的理论依据,从而形成网络民意与政府工作的良性互动。  相似文献   

Gender differences in performance in mathematics at the end of lower secondary school in Italy     

Mariagiulia Matteucci  Stefania Mignani 《Learning and individual differences》2011,21(5):543-548

The paper deals with the investigation of gender differences in performances in mathematics for Italian students at the end of lower secondary school. The study is based on a new large-scale assessment test developed and administered by the National Evaluation Institute for the School System. Given the evidence in the literature which favors males, performances of female and male students are compared using different approaches. Scores proposed by educational experts based on item subgroups were considered, while a model-based approach was used within item response theory. The results revealed a significant advantage to males in overall performance, while no meaningful differences were observed with respect to item domain and type. An interpretable item map was developed crossing expert opinions with IRT abilities, and plausible proficiency levels were defined. According to the map-based student classification, a relatively lower percentage of females fell into the highest proficiency groups with respect to males.  相似文献   

文克尔地基薄板的瞬态响应分析     

颜可珍  夏唐代 《科技通报》2006,22(1):90-94,100

利用级数展开法和Laplace--Fourier变换推导了文克尔地基上无限长板在半波正弦瞬态荷载作用下位移和应力的解析解。计算和分析了板的位移响应情况，并和弹性地基静荷载情况的位移进行了比较，讨论了荷载作用时间、地基参数及板参数等对位移响应的影响。对路面设计、品质评价及破坏机理分析有重要意义。  相似文献   

计算机应急响应系统体系研究   总被引：6，自引：0，他引：6  

连一峰  戴英侠 《中国科学院研究生院学报》2004,21(2):202-209

应急响应是维护计算机和网络系统动态安全性的关键问题 .提出了基于层次化模型的计算机应急响应系统体系结构 ,从安全服务层、系统模块层、安全研究层的角度对系统的功能需求、模块划分和相应的技术支持给出了明确的定义 ,针对计算机应急响应系统所关注的事件响应、安全监控、入侵追踪、灾难恢复等问题 ,结合向用户提供的安全咨询、安全公告、安全状况分析等服务功能 ,进行了详细的阐述 .  相似文献