不包含极大子系的S-系

设S是半群,A是S-系.首先给出了A的子系是极大子系的充分必要条件;其次利用所定义的L关系,证明了A的非空子集L是A的极大子系的充分必要条件是A\L是A的(极大)L-类;最后,定义了C-子系的概念,讨论了其性质,并利用C-子系刻画了一类S-系.证明了S-系不包含极大子系当且仅当每一个循环子系是C-子系.从而Imrich Fabrici关于半群不包含极大(左)理想的主要结论就是本文的推论.     

On the Maximal Disjoint Division in Riesz Spaces

TheRieszspaces,consideredinthispaper ,areal waysArchimedean .LetLbeaRieszspace .Foru∈L ,theprincipalidealandtheprincipalbandgeneratedbyuaredenotedbyId(u)andB(u)respectively .ForA L ,theidealandthebandgeneratedbyAaredenotedbyId(A)andB(A)respectively .Aset {ui:i∈I}ofnonzeromutuallydisjointelementsofLiscalledamaximaldis jointsystem[2 ] ifx⊥uiforalli∈Iimpliesx =0 (equiv alently ,theidealgeneratedby {ui:i∈I}isorderdenseinL) .AssumethatuiisaprojectionelementinL .ByPiwedenotetheorderp…     

Improved Estimation of Maximal Reliability for Unidimensional Multicomponent Measuring Instruments in Repeated Measure Studies

In repeated measure studies with unidimensional scales, measurement invariance, and specificity stability over time, the specificity variance in each instrument component can be identified. This article describes for that setting an improved point and interval estimation procedure for the maximal reliability coefficient associated with a given set of homogeneous measures. The method is developed within the framework of latent variable modeling and can also be readily used in longitudinal studies for improved point and interval estimation of individual measure reliability and scale reliability at each assessment occasion. The procedure is based on empirically testable conditions and is illustrated with an example.     

矩阵变换在多项式中的应用

本文根据矩阵的理论 ,定义了矩阵的一种新变换 .通过对由多项式的系数所组成的矩阵进行这种变换 ,可使多项式的除法运算和两个多项式最大公因式的求法变得简单方便 ,并且还给出了两多项式整除和互质的充要条件     

社会化小农:动机与行为

小农行为与动机的研究已经延续了数百年,根据研究的侧重点,研究的前提条件,解决小农问题的途径不相同,可以分成若干理论流派。文章根据小农行为与动机将小农理论分成四大学派,即生存小农、弱势小农、效用小农、理性小农。四大小农理论可以解释特定研究对象、特定时期的小农行为与动机,但是无法解释中国农村改革以后,生存问题基本解决,社会化程度较高的农户,即社会化小农的动机与行为。社会化小农有其独立性和特殊性,基于货币压力,崇尚“货币伦理”,追求货币收入最大化。     

一种新的频繁闭项目集挖掘算法

为了解决频繁闭项目集挖掘中时间和存储开销大的问题,提出了一种基于FC-tree（频繁闭模式树）的频繁闭项目集挖掘算法max-FCIA（最大频繁闭项目集挖掘算法）.该算法利用哈希表映射事务数据库,通过对哈希表进行操作从而得到所有频繁项目集的支持度,进而生成包含所有频繁项目的有序树.经过剪枝处理的有序树就是包含所有最小频繁闭项目集的FC-tree,最后用最小频繁闭项目集生成频繁闭项目集.实验结果表明,该算法通过映射事务数据库,减少了扫描数据库所浪费的时间,提高程序执行效率.另外,运用有效的剪枝策略,避免了不必要候选项目集的生成,节省了存储空间,实验证明该算法是有效的.     

代数方程之伽罗瓦理论的历史发展--从拉格朗日到戴德金

伽罗瓦通过引入正规子群得到代数方程根式可解的充要条件,建立了伽罗瓦理论。在这一理论的发展中,戴德金做出了重要贡献。通过对原始文献的研究,从历史的角度,在拉格朗日路线图的基础上,以正规子群为线索,勾勒出一条代数方程之伽罗瓦理论的由拉格朗日到戴德金的逻辑链。对于可解方程,伽罗瓦的工作仅说明了正规子群的存在性,戴德金在拉格朗日和伽罗瓦的基础上,给出了一个获得方程的群的正规子群的构造性方法。对这一发展的研究不仅可以呈现伽罗瓦理论早期发展的思想线索,而且有助于更好地理解伽罗瓦理论及其历史发展进程。     

m-增生算子的满值性定理的推广

将周海云关于m-增生算子的有关结论推广到带紧扰动的极大单调算子的场合。     

关于Frattini商群

设G是有限群，我们称G的所有极大子九的交为G的Frattini子群，记作Φ（G），而称G／Φ（G）为G的Frattini商群，Frattini商群对有限群构造的影响的研究结果还不多，在定理3中决定了Frattini商群的介是两个不同的系数的乘积时的有限群的构造，并且在[3]中的结果给出了简短的新证明。     

Misconceptions and biases in German students’ perception of multiple energy sources: implications for science education

Misconceptions and biases in energy perception could influence people's support for developments integral to the success of restructuring a nation’s energy system. Science education, in equipping young adults with the cognitive skills and knowledge necessary to navigate in the confusing energy environment, could play a key role in paving the way for informed decision-making. This study examined German students’ knowledge of the contribution of diverse energy sources to their nation’s energy mix as well as their affective energy responses so as to identify implications for science education. Specifically, the study investigated whether and to what extent students hold mistaken beliefs about the role of multiple energy sources in their nation’s energy mix, and assessed how misconceptions could act as self-generated reference points to underpin support/resistance of proposed developments. An in-depth analysis of spontaneous affective associations with five key energy sources also enabled the identification of underlying concerns driving people’s energy responses and facilitated an examination of how affective perception, in acting as a heuristic, could lead to biases in energy judgment and decision-making. Finally, subgroup analysis differentiated by education and gender supported insights into a ‘two culture’ effect on energy perception and the challenge it poses to science education.