The true purpose of mathematics education: A provocation

This paper features an anecdotic narration in which a fictive narrator, addressing the author of this paper, explains the functional role of mathematics education in the maintenance of the bureaucratic society. Drawing from critical philosophy and critical mathematics education, it is argued that the objective of mathematics education as realised in schools is to teach students to understand, accept, follow or at least ignore pre-defined rules as they are required for the bureaucratic administration of modern society. The theory of the narrator is underpinned with explanations that students offered in an interview study conducted by the author. Rather than supporting his alternative theory on a strict methodical basis, the narrator illustrates its explanatory strength in its confrontation with the experiences of students. The ‘provocation’ does not only lie with the narrator’s theory about the nature of mathematics education but with the fact that reality, as it is presented by the students, fits in all too well with the narrator’s explanations

Im Gedenken an Andreas Vohns

Wenn ein geschätzter und umtriebiger Kollege unsere Welt verlässt, gibt es viele Akteure, die ein letztes Mal auf sein Wirken zurückblicken und sich verabschieden möchten. Ich habe daher – weniger als Autor und mehr als Herausgeber – die Aufgabe übernommen, die folgenden kurzen Nachrufe vom Institut für Didaktik der Mathematik der Universität Klagenfurt, von aktuellen und früheren Vorstandsmitgliedern der GDM, vom Arbeitskreis „Mathematik und Bildung“, vom Arbeitskreis „Mathematikunterricht und Mathematikdidaktik in Österreich“ und von den Herausgeberinnen und Herausgebern der Zeitschrift mathematica didactica zusammenzustellen

The Electrical Breakdown of Thin Dielectric Elastomers:Thermal Effects

Dielectric elastomers are being developed for use in actuators, sensors and generators to be used in various applications, such as artificial eye lids, pressure sensors and human motion energy generators. In order to obtain maximum efficiency, the devices are operated at high electrical fields. This increases the likelihood for electrical breakdown significantly. Hence, for many applications the performance of the dielectric elastomers is limited by this risk of failure, which is triggered by several factors. Amongst others thermal effects may strongly influence the electrical breakdown strength. In this study, we model the electrothermal breakdown in thin PDMS based dielectric elastomers in order to evaluate the thermal mechanisms behind the electrical failures. The objective is to predict the operation range of PDMS based dielectric elastomers with respect to the temperature at given electric field. We performed numerical analysis with a quasi-steady state approximation to predict thermal runaway of dielectric elastomer films. We also studied experimentally the effect of temperature on dielectric properties of different PDMS dielectric elastomers. Different films with different percentages of silica and permittivity enhancing filler were selected for the measurements. From the modeling based on the fitting of experimental data, it is found that the electrothermal breakdown of the materials is strongly influenced by the increase in both dielectric permittivity and conductivity

AUTO-EXCLUSION IN MATHEMATICS EDUCATION

Auto-exclusion from mathematics education can be conceptualised as the exclusion from the mathematical discourse by the learner. While auto-exclusion has been reported in several publications, it has not yet been empirically contrasted with teaching practices and analysed for its socio-political implications. This paper can be understood as an exploratory study to gain a first research access on the above-mentioned connections. After introducing auto-exclusion on the basis of previous research and situating it socio-politically, this paper uses discourse theory to examine texts from questionnaires and interviews with secondary school students from Germany on their relationship to mathematics. Thereby, it is shown that auto-exclusion from mathematics can result from a rejection of basic assumptions of mathematical thinking, from humiliating experiences, and from teaching practices that disregard the students‟ individuality. Furthermore, it is shown that auto-excluded students are not necessarily passive and helpless victims of their educational experiences but often play an active and reflective role in defining their relationship to mathematics. Eventually, possibilities to take action are discussed

Theorien zum Mathematikunterricht

Theorien zum Mathematikunterrich

The virtual leash

University of Technology, Sydney. Faculty of Arts and Social Sciences.This exegesis serves to explore the theoretical approaches and empirical evidence of scholarly and political debate on the social relations enabled by the Internet through social media, it is a roadmap that can elucidate the processes of the attached visual and interactive methods of the creative work. Several key questions are investigated within this research that explore the relationship between the virtual leash as both a tether to cyber connections and as a constraint that binds the user to the connection. These include possible impacts of online connectivity to develop social capital and the further prospect of a blurring of the on/offline dichotomy. It asks can network technologies enhance our relationship to other cultures and identities regardless of a physical presence to increase the possibility of greater global understanding and tolerance? The exegesis complements the online documentary and a web source, which together contributes the entire assessment for the award of Masters of Creative Arts, (MCA). The creative visual essay provides a snapshot of issues and concerns that exist in present thinking of how, where, and why we embrace network technologies to guide us through virtual environments to both the advantage and the detriment of those connected. The creative work uses visual photography, text messaging, talking heads and disembodied voices to present theories on a research that daily incorporates within our everyday practices

Temporal evolution and instability in a viscoelastic dielectric elastomer

Dielectric elastomer transducers are being developed for applications in stretchable electronics, tunable optics, biomedical devices, and soft machines. These transducers exhibit highly nonlinear electromechanical behavior: a dielectric membrane under voltage can form wrinkles, undergo snap-through instability, and suffer electrical breakdown. We investigate temporal evolution and instability by conducting a large set of experiments under various prestretches and loading rates, and by developing a model that allows viscoelastic instability. We use the model to classify types of instability, and map the experimental observations according to prestreches and loading rates. The model describes the entire set of experimental observations. A new type of instability is discovered, which we call wrinkle-to-wrinkle transition. A flat membrane at a critical voltage forms wrinkles and then, at a second critical voltage, snaps into another state of winkles of a shorter wavelength. This study demonstrates that viscoelasticity is essential to the understanding of temporal evolution and instability of dielectric elastomers.Engineering and Applied Science