Inequalities for the parallel connection of resistive n-port networks

Inequalities are derived relating the impedance and admittance matrices of parallel connections without ideal transformers to the matrices of parallel connections with ideal transformers; necessary and sufficient conditions for equality are given. Equivalent conditions for equality, but not the inequalities themselves, were previously obtained in the invertible case by Lempel and Cederbaum and by Murti and Thulasiraman.     

Evaluation of a Theory of Instructional Sequences for Physics Instruction

The background of the study is the theory of basis models of teaching and learning, a comprehensive set of models of learning processes which includes, for example, learning through experience and problem‐solving. The combined use of different models of learning processes has not been fully investigated and it is frequently not clear under what circumstances a particular model should be used by teachers. In contrast, the theory under investigation here gives guidelines for choosing a particular model and provides instructional sequences for each model. The aim is to investigate the implementation of the theory applied to physics instruction and to show if possible effects for the students may be attributed to the use of the theory. Therefore, a theory‐oriented education programme for 18 physics teachers was developed and implemented in the 2005/06 school year. The main features of the intervention consisted of coaching physics lessons and video analysis according to the theory. The study follows a pre‐treatment‐post design with non‐equivalent control group. Findings of repeated‐measures ANOVAs show large effects for teachers' subjective beliefs, large effects for classroom actions, and small to medium effects for student outcomes such as perceived instructional quality and student emotions. The teachers/classes that applied the theory especially well according to video analysis showed the larger effects. The results showed that differentiating between different models of learning processes improves physics instruction. Effects can be followed through to student outcomes. The education programme effect was clearer for classroom actions and students' outcomes than for teachers' beliefs.     

Social influence or selection? Peer effects on the development of adolescents’ educational expectations in Germany

Abstract

Educational expectations are a key predictor of educational attainment. Throughout adolescence, friends increasingly function as ‘significant others’ and, thus, can affect the development of these expectations. Although scholars often interpret the clustering of students with similar expectations within friendship networks as the outcome of peer influence, a similarity of friends can also be a result of friendship selection processes and preselection due to ability tracking. We apply multilevel social network models to panel data of adolescents from Germany (1,992 ninth-grade students in 91 classes) to disentangle these mechanisms. Beyond selecting similar friends (homophily), we find that adolescents adapt their expectations towards the average expectations of their friends (social influence) but only in secondary-school tracks that support diverse educational paths. We conclude that peer socialization is important for the development of students’ educational expectations in contexts that are sufficiently heterogeneous to allow for the emergence of distinct peer milieus.     

Can international elite sport success trickle down to mass sport participation? Evidence from Danish team handball

Many scholars do not find evidence of a trickle-down effect from elite sport success to mass sport participation. Contrary to what is assumed by the trickle-down effect “theorem”, successful elite sportspeople do not seem to inspire amateurs to take up sport themselves. However, recent studies present evidence that elite sport can have an influence. In this article, we apply regression models on time series data from one of the most successful Danish sports, team handball. Our findings are mixed, but lean towards supporting scholars who argue that trickle-down effects are not necessarily an inherent part of international sporting success. Further studies should examine more sports to identify where trickle-down effects occur and why.     

Informationen des Bundesinstituts für Sportwissenschaft (BISp)

BISp-Informationen

Informationen des Bundesinstituts für Sportwissenschaft (BISp)     

Mobilitätskonzept in Sporttherapie und -wissenschaft

The international classification of functioning, disability and health (ICF) is a concept developed for the healthcare sector by the World Health Organization, which considers the health problems of a person with respect to functional ability, impairments and context factors. Mobility is an important basic functional element, central health criterion and an important prerequisite for participation in social life. In addition to all routinely relevant daily movements (e.g. walking, lifting and carrying), activities at the workplace and sport-related activities are also taken into consideration. Because mobility is internationally established as a central criterion of health by the World Health Organization, this results in a series of interesting connecting factors from sport scientific and kinesthesiological perspectives: movement is the central object of kinesthesiology and exercise therapy. Mobility is of exceptional importance for human existence and dealing with the world at large. Analogous to the discussion on basic motor competences with respect to compatibility in educational sciences, utilization of the ICF can be the basis for a common language in the medical-therapeutic milieu. The orientation to mobility allows the targets, contents and methods of exercise therapy to be addressed for the context-related importance in individual cases. This article presents possible perspectives for sport scientific disciplines, sport and exercise therapy with respect to mobility. The importance of mobility for health is emphasized and the relevance is discussed based on the development of diagnostic procedures and application of therapy.     

什么是正统马克思主义?

这篇卢卡奇于1919年发表的《什么是正统马克思主义?》是后来收录在《历史与阶级意识》中的同名文章的最初稿。在这篇研究马克思主义哲学的处女作中,卢卡奇不仅初步规定了“历史”“总体”“辩证法”“阶级”等核心概念的基本内涵和内在联系,而且建构起了他理解马克思主义辩证法的基础逻辑构架。可以说,这篇文章是构成青年卢卡奇“新世界观萌芽”的纲领性文件。因此,它对于我们深入把握卢卡奇的思想发展脉络具有不可忽视的重要意义。今年恰逢该文发表一百周年,在此将其译为中文,以飨读者。