Network structure, self-organization, and the growth of international collaboration in science

Different approaches have been used to analyse international collaboration in science but none can fully explain its rapid growth. Using international co-authorships, we test the hypothesis that international collaboration is a self-organising network. Applying tools from network analysis, the paper shows that the growth of international co-authorships can be explained based on the organising principle of preferential attachment, although the attachment mechanism deviates from an ideal power-law. Several explanations for the deviation are explored, including that of the influence of institutional constraints on the mechanism of self-organisation.     

AutoFocus – Ein Werkzeugprototyp zur Entwicklung eingebetteter Systeme

Der Beitrag stellt AutoFocus vor, einen Werkzeugprototyp zur Entwicklung verteilter, eingebetteter Systeme auf der Grundlage formaler Techniken. AutoFocus unterstützt die Systementwicklung mit integrierten, im wesentlichen graphischen Beschreibungstechniken, mit deren Hilfe sowohl unterschiedliche Sichten als auch verschiedene Abstraktionsebenen eines Systems beschrieben werden. Um konsistente und vollst?ndige Beschreibungen sicherzustellen, bietet AutoFocus die M?glichkeit, Konsistenzbedingungen zu formulieren und Systembeschreibungen daraufhin zu überprüfen. Aus ausführbaren Spezifikationen k?nnen Prototypen des entwickelten Systems erzeugt werden und in einer Simulationsumgebung ausgeführt und visualisiert werden. Zur formalen Verifikation von Systemeigenschaften verfügt AutoFocusüber Anbindungen an Modellprüfungswerkzeuge wie -cke oder SMV.     

Kinematic differences of elite and high-performance tennis players in the cross court and down the line forehand

This study identified and compared the full body kinematics of different skill levels in the forehand groundstroke when balls were hit cross court and down the line. Forty-three three-dimensional retroreflective marker trajectories of six elite and seven high-performance players were recorded using an eight-camera 400 Hz, Vicon motion analysis system. The six highest horizontal velocity forehands with reliable kinematics of all participants were analysed for each specific situation (a total of 156 analysed shots). Significant differences (p < 0.01) and large effect sizes were observed between elite and high-performance players in linear velocity of the shoulder (2.0 vs. 1.2 m/s), angular velocity of the pelvis (295 vs. 168 degrees/s), and angular velocity of the upper trunk (453 vs. 292 degrees/s) at impact. The elite group showed a tendency towards higher racquet velocities at impact (p < 0.05). No significant differences were found in angular displacement of the racquet, hip alignment, or shoulder alignment at the completion of the backswing; nor did angular displacement vary significantly at impact. Irrespective of the group, different shoulder, hip, and racquet angles were found at impact, depending on the situation. The results should assist coaches when striving to improve their players' forehand.     

Re-mythologizing mathematics through attention to classroom positioning

With our conceptualization of Harré and van Langenhove’s (1999) positioning theory, we draw attention to immanent experience and read transcendent discursive practices through the moment of interaction. We use a series of spatial images as metaphors to analyze the way positioning is conceptualized in current mathematics education literature and the way it may be alternatively conceptualized. This leads us to claim that changing the way mathematics is talked about and changing the stories (or myths) told about mathematics is necessary for efforts to change the way mathematics is done and the way it is taught.

Geheimnisvoller Transfer?

The term “transfer” in the context of learning and the application of research results should help us understand and support processes of applying this knowledge better. The article analyzes prerequisites and conditions for the transfer of educational knowledge and evidence to educational practice, which seem reasonable, but are often neglected. Model programs with empirically tested innovations serve as examples for the discussion of fruitful conditions in the evaluation research itself as well as in the context of application. Examples of “best” practice, finally, are used to sketch challenges and approaches for an educational research focused on transfer.     

Eckpunkte des Universitätsrechts-Änderungsgesetzes 2009 (Teil 1)

In Abkehr von ihrer Einrichtung als auf demokratischer Partizipation basie- render Bundesdienststellen, nach UOG, wurden die staatlichen Universitäten ab dem UOG 1993 zunehmend in Richtung eigenverantwortlicher "Bildungsbetriebe" umge- baut. Diese auf Deregulierung und Dezentralisierung universitärer Handlungspara- meter abstellende Entwicklung fand ihren vorläufigen Höhepunkt in der Umwandlung der Universitäten in vollrechtsfähige juristische Personen, durch das UG (2002). Die aufrechte Funktion des Staates als Erhalter und insb Financier der Universitäten hat zu einem auf universitäre Leistung und Verantwortung gegründeten Beziehungs- system zwischen Staat, Gesellschaft und Universitäten geführt, das auch mit Rechts- unsicherheiten und Friktionen behaftet ist. Der bisher letzte Schritt in Richtung des intendierten umfassenden "Kulturwandels" der Universitäten wurde mit dem Universitätsrechts-Änderungsgesetz 2009 getan, das eine umfassende Novellierung der bisher geltenden Rechtslage beinhaltet.     

Feeling number: grounding number sense in a sense of quantity

Drawing on results from psychology and from cultural and linguistic studies, we argue for an increased focus on developing quantity sense in school mathematics. We explore the notion of “feeling number”, a phrase that we offer in a twofold sense—resisting tendencies to feel numb-er (more numb) by developing a feeling for numbers and the quantities they represent. First, we distinguish between quantity sense and the relatively vague notion of number sense. Second, we consider the human capacity for quantity sense and place that in the context of related cultural issues, including verbal and symbolic representations of number. Third and more pragmatically, we offer teaching strategies that seem helpful in the development of quantity sense coupled with number sense. Finally, we argue that there is a moral imperative to connect number sense with such a quantity sense that allows students to feel the weight of numbers. It is important that learners develop a feeling for number, which includes a sense of what numbers are and what they can do.