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61.
Starting from the notion of h-type indices for infinite sequences we investigate if these indices satisfy natural inequalities related to the arithmetic, the geometric and the harmonic mean. If f denotes an h-type index, such as the h- or the g-index, then we investigate inequalities such as min(f(X),f(Y)) ≤ f((X?+?Y)/2) ≤ max(f(X), f(Y)). We further investigate if: f(min(X,Y)) = min(f(X),f(Y)) and if f(max(X,Y)) = max(f(X),f(Y)). It is shown that the h-index satisfies all the equalities and inequalities we investigate but the g-index does not always, while it is always possible to find a counterexample involving the R-index. This shows that the h-index enjoys a number of interesting mathematical properties as an operator in the partially ordered positive cone (R+) of all infinite sequences with non-negative real values.In a second part we consider decreasing vectors X and Y with components at most at distance d. Denoting by D the constant sequence (d,d,d, …) and by Y-D the vector (max(yr-d), 0)r, we prove that under certain natural conditions, the double inequality h(Y-D) ≤ h(X) ≤ h(Y?+?D) holds.  相似文献   
62.
宋代理学家们所倡导的理想人格不仅仅是社会伦理的内涵,它包含着宋人对人生形而上的思考。虽然山水画学中的“理”和理学的“理”含义不完全相同,但它无疑是理学这个时代强音中的一个音符。画家笔下的层峦叠嶂、烟柳渔浦、寒林远水表达的是创作主体对世界与人生的思考,以有形之象呈现内在之理,画家在“理趣”的玩味中得到性情的陶染和灵魂的提升。宋代山水精、妙、神、逸诸品众多当与其兼备理、气、趣有着直接关系。而理、气、趣又来自创作主体所受到的理学人格的薰陶。宋代山水画取得的辉煌成就,不能无视宋代理学的积极影响。  相似文献   
63.
网络信息检索中,逻辑运算符AND连接检索词的顺序很大程度上会影响检索效率.论文首先分析、介绍了the Staceys测度方法在改善AND检索效率中发挥的作用,并在此基础上提出简化了的测度算法,最后通过实例说明其实现步骤.  相似文献   
64.
作为大学老师,为了达到好的教学效果,我们必须能够做好两项活动,既要做好课程设计,又要做好师生互动。就这两项活动而言,我们的课程设计能力常常是制约因素。《创造意义深远的学习经历:大学课程整合设计方案》一书作者,美国奥克拉荷马大学教学发展项目部主任迪.芬克博士撰写了一份大学课程设计的自学指南,旨在给大家介绍一套系统有效的课程设计程式,帮助大家学会怎样进行课程设计。指南包括课程整合设计的三个主要阶段,每阶段包括开篇的介绍性评价,读者可以加以使用的工作簿,以及读者在课程设计过程中可以对自己提出的一些问题,以对自己的设计实践进行推敲。  相似文献   
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This study extended validity evidence for multidimensional measures of coaching competency derived from the Coaching Competency Scale (CCS; Myers, Feltz, Maier, Wolfe, & Reckase, 2006) by examining use of the original rating scale structure and testing how measures related to satisfaction with the head coach within teams and between teams. Motivation, game strategy, technique, and character building comprised the dimensions of coaching competency. Data were collected from athletes (N = 585) nested within intercollegiate men's (g = 8) and women's (g = 13) soccer and women's ice hockey (g = 11) teams (G = 32). Validity concerns were observed for the original rating scale structure and the predicted positive relationship between motivation competency and satisfaction with the coach between teams. Validity evidence was offered for a condensed post hoc rating scale and the predicted relationship between motivation competency and satisfaction with the coach within teams.  相似文献   
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A bond graph model is derived for the geometric constraints of a three-axis flight table. Gimbal dynamics are easily added even in asymmetrical and unbalanced cases. A method is introduced to make the local dependent inertias computable. The bond graph compares favourably to the Lagrangian approach as to modelling effort and accessibility of intermediate variables as well as having computational advantages.  相似文献   
70.
The chief purpose of this study was to identify characteristics that distinguish approach as an attachment behavior from approach serving other behavioral systems. Locomotor approaches of 16 male and 10 female white middle-class infants to an attachment figure (the mother) and to a nonattachment figure (the visitor-observer) were examined under naturalistic conditions at home. Observations were made during 4-hour home visits at 3-week intervals; those from 26 to 54 weeks were used. When approach was examined in a free-choice situation and without regard to behavioral context, infants approached the mother proportionally (though slightly) more often than the visitor (p less than .05). In 2 behavioral contexts, however, spontaneous infant approaches were sharply differential to the mother; approaches accompanied by crying and approaches terminating in a pickup appeal were directed almost exclusively to the mother (p less than .0001 for both). Touching upon completion of the approach was not differential, except in the context of a pickup appeal. Object-oriented approaches were more often directed to the visitor than to the mother (p less than .002) and may be either exploratory or affiliative. It is suggested that neither approach nor touching can be assumed to serve the attachment system without consideration of context- both environmental and behavioral.  相似文献   
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