A stochastic framework for multiscale strength prediction using adaptive discontinuity layout optimisation (ADLO)

The prediction of strength properties of matrix-inclusion materials, which in general are random in nature due to their spatial distribution and variation of pores, particles, and matrix-inclusion interfaces, plays an important role with regard to the reliability of materials and structures. The recently developed discontinuity layout optimisation (DLO) [18] and adaptive discontinuity layout optimisation (ADLO) [4], which can be used for determination of strength properties of materials [3, 4] and structures [9], are included in a stochastic framework, using random variables. Therefore different material properties, influencing the overall strength of the matrix-inclusion material (e.g. matrix and inclusion strength, number and distribution of pores/particles) in a considered RVE are assumed to follow certain probability distributions [12]. A sensitivity study for the identification of material parameters showing the largest influence on the strength of the considered matrix-inclusion materials is performed. The obtained results provide first insight into the nature of the reliability of strength properties of matrix-inclusion materials, paving the way to a better understanding and finally improvement of the effective strength properties of matrix-inclusion materials

Discontinuity layout optimization in upscaling of effective strength properties in matrix-inclusion materials

The prediction of strength properties of engineering materials, which in general are time dependent due to chemical reactions and deterioration processes, plays an important role during manufacturing and construction as well as with regard to durability aspects of materials and structures. On the one hand, the speed of production processes and the quality of products may be significantly increased by improved material performance at early ages. On the other hand, the life time of materials and structures can be enlarged and means of repair and maintenance can be optimized. For determination of strength properties of composite materials, a multiscale approach is proposed in this paper. For upscaling of strength properties, numerical limit analysis considering discontinuity layout optimization (DLO) is employed. In a first step, DLO is applied to two-phase material systems, with the matrix being represented by node clouds. In this paper, adaptive techniques regarding the spatial distribution of nodes thus the discontinuity generation are introduced in DLO, improving the computational performance of DLO within upscaling of strength properties

Greener households? The effectiveness of smart meters in reducing energy consumption levels in the DACH region

With public opinion shifting to a believe in climate change in the early 2000s the interest in energy efficiency has been increasing. EU Directives set the goal of deploying smart meters if cost efficient for providing more detailed energy consumption. The main goal is to better inform consumers and to give individual households the power to change possibly energy wasting behaviours. This paper evaluates through a literature review the effectiveness of intelligent electricity metering systems with a focus on the DACH region, the provision of different types of feedback and its persistence. It can be concluded that energy feedback enabled by smart meters can lead to savings in the range of 0% to 4.5% in this region. If feedback is provided continuously savings persist. However, several aspects have to be considered to ensure effectiveness of smart meter deployment

A generative growth model for thalamocortical axonal branching in primary visual cortex

Axonal morphology displays large variability and complexity, yet the canonical regularities of the cortex suggest that such wiring is based on the repeated initiation of a small set of genetically encoded rules. Extracting underlying developmental principles can hence shed light on what genetically encoded instructions must be available during cortical development. Within a generative model, we investigate growth rules for axonal branching patterns in cat area 17, originating from the lateral geniculate nucleus of the thalamus. This target area of synaptic connections is characterized by extensive ramifications and a high bouton density, characteristics thought to preserve the spatial resolution of receptive fields and to enable connections for the ocular dominance columns. We compare individual and global statistics, such as a newly introduced length-weighted asymmetry index and the global segment-length distribution, of generated and biological branching patterns as the benchmark for growth rules. We show that the proposed model surpasses the statistical accuracy of the Galton-Watson model, which is the most commonly employed model for biological growth processes. In contrast to the Galton-Watson model, our model can recreate the log-normal segment-length distribution of the experimental dataset and is considerably more accurate in recreating individual axonal morphologies. To provide a biophysical interpretation for statistical quantifications of the axonal branching patterns, the generative model is ported into the physically accurate simulation framework of Cx3D. In this 3D simulation environment we demonstrate how the proposed growth process can be formulated as an interactive process between genetic growth rules and chemical cues in the local environment

Demography of European regions

Das Ziel dieser Diplomarbeit ist die Entwicklung einer demographischer Typologie europäischer Regionen und die Verknüpfung dieser Klassifikation mit sozio-ökonomischen Indikatoren. In diesem Sinne wird nicht nur auf den Status Quo europäischer Länder eingegangen, sondern vor allem die regionale Ebene von NUTS 2 diskutiert. Die neu entwickelte Klassifikation europäischer Regionen nach demographischen Merkmalen bezieht sich auf das Jahr 2005 und unterscheidet sieben Regionstypen. Weitere Analysen in dieser Diplomarbeit beschäftigen sich mit den demographischen und sozio-ökonomischen Potenzialen und Herausforderungen der verschiedenen Regionstypen. Die Typologie ermöglicht die Identifikation homogener räumlicher Muster innerhalb des vorherrschenden demographischen Pluralismus in Europa zu Beginn des 21. Jahrhunderts. Die demographische Diversität von Regionen spiegelt sich nur zum Teil in der Geographie von Nationalstaaten wider und kann auch nur bedingt mit traditionellen dichotomen Kategorien – wie zum Beispiel Bevölkerungswachstum auf der einen und Bevölkerungsalterung auf der anderen Seite – beschrieben werden. Eine räumliche Aggregation im Sinne einer Klassifikation ermöglicht die Erfassung ähnlich gelagerter demo-graphischer Herausforderungen und entsprechender regionalpolitischer Lösungsansätze.The purpose of this diploma thesis is to develop a typology of European regions based on demographic variables and the link the resulting typology to economic indicators. In this context, this thesis does not only discuss the state of the demography of European countries, but rather concentrates on European regions at the scale of NUTS 2. Based on the awareness, that particular demographic trends and patterns exist across Europe, a classifica-tion of European regions based on demographic variables was developed. This typology of 286 NUTS 2 regions is a comprehensive classification of the demographic structure and short-term trends in the EU27+4 and distin-guishes between seven types of regions, which enable the user to capture the demographic diversity of European regions in 2005 at first glance. Additional analyses illustrate the demographic and socio-economic character-istics of the different types of regions in terms of potentials and challenges. The typology of the demographic status sheds light on the prevailing demo-graphic pluralism across Europe. It identifies diverse and heterogeneous spatial patterns beyond traditional categories like population growth and decline, which are shaping the demographic landscape of European regions at the beginning of the 21st century. When zooming beyond the geography of nation states, the often-underestimated extent of regional heterogeneity of demographic characteristics becomes apparent. In order to obtain homoge-neous spatial patterns, a regional aggregation in terms of clustering makes sense. This regional level classification of the demographic status of Euro-pean NUTS 2 regions facilitates the identification of similar challenges and solutions and enables to compare the various impacts of different regional policies in the context of social and economic cohesion

The KdV and Whitham limit for a spatially periodic Boussinesq model

Wir betrachten die KdV-Approximation und die Whitham-Approximation für ein räumlich periodisches Boussinesq-Modell. Wir zeigen Abschätzungen der Differenz zwischen der KdV- beziehungsweise der Whitham-Approximation und echten Lösungen des ursprünglichen Modells, welche garantieren, dass diese Amplituden-Gleichungen korrekte Vorhersagen über die Dynamik des räumlich periodischen Boussinesq-Modells über die natürlichen Zeitskalen machen. Der Beweis basiert auf Blochwellenanalysis und Energieabschätzungen

Accuracy of KinectOne to quantify kinematics of the upper body

Motion analysis systems deliver quantitative information, e.g. on the progress of rehabilitation programs aimed at improving range of motion. Markerless systems are of interest for clinical application because they are low-cost and easy to use. The first generation of the Kinect™ sensor showed promising results in validity assessment compared to an established marker-based system. However, no literature is available on the validity of the new 'Kinect™ for Xbox one' (KinectOne) in tracking upper body motion. Consequently, this study was conducted to analyze the accuracy and reliability of the KinectOne in tracking upper body motion. Twenty subjects performed shoulder abduction in frontal and scapula plane, flexion, external rotation and horizontal flexion in two conditions (sitting and standing). Arm and trunk motion were analyzed using the KinectOne and compared to a marker-based system. Comparisons were made using Bland Altman statistics and Coefficient of Multiple Correlation. On average, differences between systems of 3.9±4.0° and 0.1±3.8° were found for arm and trunk motion, respectively. Correlation was higher for the arm than for the trunk motion. Based on the observed bias, the accuracy of the KinectOne was found to be adequate to measure arm motion in a clinical setting. Although trunk motion showed a very low absolute bias between the two systems, the KinectOne was not able to track small changes over time. Before the KinectOne can find clinical application, further research is required analyzing whether validity can be improved using a customized tracking algorithm or other sensor placement, and to analyze test-retest reliability