Smart Technology for Telerehabilitation: A Smart Device Inertial-sensing Method for Gait Analysis

The aim of this work was to develop and validate an iPod Touch (4th generation) as a potential ambulatory monitoring system for clinical and non-clinical gait analysis. This thesis comprises four interrelated studies, the first overviews the current available literature on wearable accelerometry-based technology (AT) able to assess mobility-related functional activities in subjects with neurological conditions in home and community settings. The second study focuses on the detection of time-accurate and robust gait features from a single inertial measurement unit (IMU) on the lower back, establishing a reference framework in the process. The third study presents a simple step length algorithm for straight-line walking and the fourth and final study addresses the accuracy of an iPod’s inertial-sensing capabilities, more specifically, the validity of an inertial-sensing method (integrated in an iPod) to obtain time-accurate vertical lower trunk displacement measures. The systematic review revealed that present research primarily focuses on the development of accurate methods able to identify and distinguish different functional activities. While these are important aims, much of the conducted work remains in laboratory environments, with relatively little research moving from the “bench to the bedside.” This review only identified a few studies that explored AT’s potential outside of laboratory settings, indicating that clinical and real-world research significantly lags behind its engineering counterpart. In addition, AT methods are largely based on machine-learning algorithms that rely on a feature selection process. However, extracted features depend on the signal output being measured, which is seldom described. It is, therefore, difficult to determine the accuracy of AT methods without characterizing gait signals first. Furthermore, much variability exists among approaches (including the numbers of body-fixed sensors and sensor locations) to obtain useful data to analyze human movement. From an end-user’s perspective, reducing the amount of sensors to one instrument that is attached to a single location on the body would greatly simplify the design and use of the system. With this in mind, the accuracy of formerly identified or gait events from a single IMU attached to the lower trunk was explored. The study’s analysis of the trunk’s vertical and anterior-posterior acceleration pattern (and of their integrands) demonstrates, that a combination of both signals may provide more nuanced information regarding a person’s gait cycle, ultimately permitting more clinically relevant gait features to be extracted. Going one step further, a modified step length algorithm based on a pendulum model of the swing leg was proposed. By incorporating the trunk’s anterior-posterior displacement, more accurate predictions of mean step length can be made in healthy subjects at self-selected walking speeds. Experimental results indicate that the proposed algorithm estimates step length with errors less than 3% (mean error of 0.80 ± 2.01cm). The performance of this algorithm, however, still needs to be verified for those suffering from gait disturbances. Having established a referential framework for the extraction of temporal gait parameters as well as an algorithm for step length estimations from one instrument attached to the lower trunk, the fourth and final study explored the inertial-sensing capabilities of an iPod Touch. With the help of Dr. Ian Sheret and Oxford Brookes’ spin-off company ‘Wildknowledge’, a smart application for the iPod Touch was developed. The study results demonstrate that the proposed inertial-sensing method can reliably derive lower trunk vertical displacement (intraclass correlations ranging from .80 to .96) with similar agreement measurement levels to those gathered by a conventional inertial sensor (small systematic error of 2.2mm and a typical error of 3mm). By incorporating the aforementioned methods, an iPod Touch can potentially serve as a novel ambulatory monitor system capable of assessing gait in clinical and non-clinical environments

Forecasting the Demand for Emergency Medical Services

Accurate forecast of the demand for emergency medical services (EMS) can help in providing quick and efficient medical treatment and transportation of out-of-hospital patients. The aim of this research was to develop a forecasting model and investigate which factors are relevant to include in such model. The primary data used in this study was information about ambulance calls in three Swedish counties during the years 2013 and 2014. This information was processed, assigned to spatial grid zones and complemented with population and zone characteristics. A Zero-Inflated Poisson (ZIP) regression approach was then used to select significant factors and develop the forecasting model. The model was compared to the forecasting model that is currently incorporated in the EMS information system used by the ambulance dispatchers. The results show that the proposed model performs better than the existing one

Post-Demolition Autoclaved Aerated Concrete: Recycling Options And Volume Prediction In Europe

Autoclaved aerated concrete (AAC) is an increasingly used building material due to its exceptional thermal properties. Post-demolition AAC is mainly disposed in landfills because of lacking established recycling processes. However, the growing demand for sustainable products, greenhouse gas reduction, decreasing landfill capacities and new legal frameworks require recycling options for post-demolition AAC. Current research includes using post-demolition AAC recycling in the production of lightweight aggregate concrete, lightweight mortar, no-fines concrete, and floor screed. Even closed-loop recycling could be achieved by adding finely ground post-demolition AAC in the AAC production process or by producing belite cement clinker from post-demolition AAC as a substitution for Portland cement. Predicting the generation of post-demolition AAC volumes is crucial for a recycling and circular management of AAC. But, post-demolition AAC volumes in Europe are currently neither recorded in statistics nor investigated in comprehensive studies. Therefore, a post-demolition AAC prediction model is presented that quantifies post-demolition AAC on a national and European level. Results show low volumes in South East, Western, and Southern Europe as well as Scandinavia due to small market sizes. In North West and Central Europe, especially the UK (700,000 m³) and Germany (1,200,000 m³) in 2020 drive post-demolition AAC volumes. The most significant post-demolition AAC volumes occur in Eastern Europe, especially in Poland (1,800,000 m³) and Russia (3,900,000 m³) in 2020. While relative volumes between the regions stay similar, the absolute post-demolition AAC volumes in Europe will nearly double in the next decade from 12.3 to 22.0 million m³

Influence des paramètres de formulation sur la texturation et la structuration des géopolymères

In the context of conditioning of nuclear waste, geopolymers represent a potential alternative to conventional hydraulic binders. Currently, it is recognized that the formation of geopolymer proceeds according to a mechanism of dissolution - restructuring - polymerization resulting in a solid material. Despite the availability of many studies to understand these mechanisms, the precise relationship between the chemical nature of the activating solution, the geopolymerization process and the final microstructure should be determined from the point of view of the texturing and the structural evolution of the material. In this work, several parameters were studied: the nature of the alkali activator, the silica concentration and the addition of an aluminum source. It appears that the chemical environment of the silicate or aluminosilicate precursors is controlled by the activating solution composition. During the consolidation of the geopolymer network, these precursors play an important role on the dissolution rate of metakaolin, the size, the rearrange¬ment and the aggregation of aluminosilicate oligomers involved in the porous solid network formation. Subsequently, some characteristics of the porous network which are controlled by the size and the rearrangement of oligomers vary slightly over time. The refinement of the porosity associated to first, a densification of the solid network, and secondly, a partial closure of the porosity at the nanometer scale leads to an increase in the pore size and a decrease of the pore volume.Dans le cadre du conditionnement des déchets nucléaires, les géopolymères représentent une alternative potentielle aux liants hydrauliques classiques. A ce jour, il est admis que la formation des géopolymères procède selon un mécanisme de dissolution - restructuration - polymérisation conduisant à un matériau solide. Cependant, les liens précis entre la composition de la solution d’activation, le déroulement des réactions de géopolymérisation et la microstructure finale doivent être déterminés du point de vue de la texturation et de l’évolution structurale du matériau. Ainsi plusieurs paramètres de formulation ont été étudiés : la nature de l’activateur alcalin, la concentration en silice et l’ajout d’une source d’aluminium. Il apparait que l’environnement chimique des précurseurs silicatés ou alumino-silicatés est contrôlé par les paramètres de formulation constitutifs de la solution d’activation. Lors de la formation du réseau géopolymérique, ces précurseurs jouent un rôle primordial sur la cinétique de dissolution du métakolin, la taille, l’arrangement et l’agrégation des oligomères alumino-silicatés participant à la formation du réseau poreux. A plus long terme, certaines caractéristiques du réseau poreux qui sont-elles même contrôlées par la taille et l’agencement des oligomères, varient légèrement au cours du temps. Le réarrangement de la structure poreuse associé d’une part à la densification du réseau solide, et d'autre part à la fermeture partielle de la porosité conduit à une légère augmentation de la taille des pores et à une diminution du volume poreux accessible

Gender in der Psychologie : Zur Diskrepanz zwischen Erkenntnisstand und Implementierung in die Fachkultur

Die psychologische Grundlagenforschung hat in den letzten Jahrzehnten ein immenses Wissen zur Psychologie der Geschlechter zusammengetragen, und zwar aus allen möglichen psychologischen Perspektiven (Steins 2010). Wie hat sie das geschaffene Wissen für die eigene Fachkultur genutzt? Nach einer kurzen Darstellung zentraler Erkenntnisse der psychologischen Geschlechterforschung und genderspezifischer berufsbiographischer Muster in der Psychologie soll die Implementierung der genderbezogenen Erkenntnisse in die Fachkultur der Psychologie als Wissenschaftsdisziplin beschrieben werden

Frauen im Grundschullehrer*innenberuf

Die Autorin fokussiert Frauen im Grundschullehrer*innenberuf. Dabei beleuchtet sie die Thematik vom Kinde aus und legt zunächst auf Basis theoretischer Fundierung Bedarfe der Lernenden in dieser Altersgruppe fest. Dabei profitieren Kinder in ihrem unterrichtlichen Erleben von Wärme und Interaktionsgestaltung, die auch besonders wichtig sind für die Entwicklung von Selbstvertrauen und eigenen Konzepten. Auch gesellschaftliche Ziele wie die Ausbildung eines demokratischen „Rückrats“ profitieren von diesen Eigenschaften. Gleichzeitig sind aber auch Wärme und Kompetenz mit Geschlechterstereotypen verwoben, so wird Wärme eher weiblich konnotiert und Kompetenz männlich. Eine Auflösung solcher Stereotype ist daher dringend erforderlich. (DIPF/Orig.