Accuracy and precision of loadsol® insole force-sensors for the quantification of ground reaction force-based biomechanical running parameters

Force plates represent the “gold standard” in measuring running kinetics to predict performance or to identify the sources of running-related injuries. As these measurements are generally limited to laboratory analyses, wireless high-quality sensors for measuring in the field are needed. This work analysed the accuracy and precision of a new wireless insole forcesensor for quantifying running-related kinetic parameters. Vertical ground reaction force (GRF) was simultaneously measured with pit-mounted force plates (1?kHz) and loadsol^® sensors (100?Hz) under unshod forefoot and rearfoot running-step conditions. GRF data collections were repeated four times, each separated by 30 min treadmill running, to test influence of extended use. A repeated-measures ANOVA was used to identify differences between measurement devices. Additionally, mean bias and Bland–Altman limits of agreement (LoA) were calculated. We found a significant difference (p?® devices for these parameters. For these same parameters, the LoA analysis showed that 95% of all measurement differences between insole and force plate measurements were less than 12%, demonstrating high precision of the sensors. However, highly dynamic behaviour of GRF, such as force rate, is not yet sufficiently resolved by the insole devices, which is likely explained by the low sampling rate.     

Offensichtlich unsichtbar Die P?dagogisierung des Umgangs mit Wissen im Kontext des lebenslangen Lernens

Der vorliegende Beitrag besch?ftigt sich unter Bezugnahme auf einen systemtheoretischen Kommunikationsbegriff mit der (p?dagogischen) Strukturierung des Lernens Erwachsener. Er geht von der These aus, dass die P?dagogisierung des lernbezogenen Umgangs mit Wissen im Erwachsenenalter unsichtbar (gemacht) wird. Auf der Grundlage eines abgeschlossenen DFG-Projekts werden unterschiedliche Formen p?dagogischer Kommunikation dargestellt und das in ihren Settings, ihrer kommunikativen Verfasstheit und den Mustern ihrer Strukturierung eingelagerte Invisibilisierungspotenzial herausgearbeitet. Vor diesem Hintergrund wird das Konzept des Lebenslangen Lernens als eine entwickelte Form des Umgangs mit dem Paradox der (Un-)Sichtbarkeit p?dagogischer Kommunikation interpretiert. Was diese Institutionalisierungsform des Lernens kennzeichnet, ist somit eine doppelt gegenl?ufige Gleichzeitigkeit von Visibilisierung und Invisibilisierung.     

Casting the die before the die is cast: the importance of the home numeracy environment for preschool children

Mathematical competencies are important not only for academic achievement at school but also for professional success later in life. Although we know a lot about the impact of “Home Literacy Environment” on the development of early linguistic competencies, research on “Home Numeracy Environment” (HNE) and the assessment of its influence on the development of mathematical abilities is in its infancy. We still lack studies analysing this relationship and simultaneously controlling for other variables concerning the individual and the environment. Thus, in this article, we focussed on the development of mathematical competencies in a sample of 609 German children from the end of kindergarten until the end of Grade 1. In particular, we were interested in the role HNE plays in regard to this development while controlling for age, sex, intelligence, rapid naming, number span, linguistic competencies, kindergarten attendance and socioeconomic status. Moreover, HNE was compared between families with or without a history of mathematical disability. HNE was not only an important predictor of mathematical abilities at the end of kindergarten, but it also influenced the further development of mathematical competencies above and beyond its initial impact. Families with a history of dyscalculia provided a more unfavourable HNE than families with no such problems. Results are shown in a structural equation model, which highlights the importance of HNE. The findings indicate that those involved in policy and intervention should focus more on the learning environments in families to improve children's achievement.     

Developing and validating test items for first-year computer science courses

We report on the development, validation, and implementation of a collection of test items designed to detect misconceptions related to first-year computer science courses. To this end, we reworked the development scheme proposed by Almstrum et al. (SIGCSE Bulletin 38(4):132–145, 2006) to include students’ artifacts and to simultaneously incorporate think-aloud interviews and flash tests. We also investigated to what extent the practical efficiency of detecting certain misconceptions could be increased without significantly affecting the sensitivity of the instrument, and present positive and negative results regarding this goal. The results of a first transfer and implementation study suggest that it is indeed possible to use the test items in a large-scale practical setting – both as diagnostic instruments and as interventions.     

Home Literacy Environment and the beginning of reading and spelling

Reading and writing are necessary prerequisites for a successful school career. Therefore it is important to identify precursor variables which predict these abilities early in order to identify children possibly at risk of developing reading or spelling difficulties. Relevant precursors include letter knowledge, phonological awareness (PA), vocabulary, and cognitive abilities. Moreover, also social aspects such as the socioeconomic status of the family (SES), the migration background and the “Home Literacy Environment” (HLE) are of importance. So far, only a few studies are available which analyse the early development of different possible explanatory factors simultaneously in the years before and after school enrolment. In particular, the relative impact of HLE on early and later linguistic competencies in a German context remains unclear. Thus, in our longitudinal study, covering the period from kindergarten to Grade 1, we focused on the role HLE plays in the development of language competencies of 921 German children, compared to the impact of several other important variables.     

Effiziente Informationssuche im Internet mit Hilfe mobiler Programme

Zusammenfassung.   Die Bereitstellung eines pr?zisen, effizienten und m?glichst vollst?ndigen Zugriffs auf aktuelle Informationen im Internet ist eine grundlegende Voraussetzung für die Weiterentwicklung des elektronischen Handels. Dieser Beitrag zeigt, wie themenspezifische Suchwerkzeuge mit Hilfe mobiler Programme eine solche Bereitstellung leisten k?nnen. Der vorgestellte Ansatz wird durch messdaten-basierte Simulationen sowie anhand einer Fallstudie evaluiert. Eingegangen am 15. Dezember 1999 / Angenommen am 10. April 2000