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This thesis addresses the observation, analysis and dynamics of waves as being trapped, generated and focused by sloping topography. ---Shelf waves with diurnal tidal frequency off Greenland--- Tidal analysis has been carried out on current measurements at a “cross-shelf” transect off Greenland at 71 N. The diurnal tides manifest themselves mainly as a barotropic continental shelf wave, travelling southward along the shelf slope. This follows from the amplitude distribution of the diurnal tidal components and from the rotation sense of the tidal ellipses at different cross-slope locations, as calculated with simple two-dimensional models. The well organized cross-slope pattern of the velocity amplitudes is absent in observations further north near 75 N. These observations suggest that the local vanishing of the group velocity, which is caused by topography, is of importance for the existence and local amplification of these continental shelf waves with diurnal tidal frequency. ---Tidal and residual currents near the shelf break in Biscay--- Internal-wave energy in continuously stratified fluids propagates in the vertical plane, at an angle set by the wave, buoyancy and Coriolis frequencies. Repeated Acoustic Doppler Current Profiler observations on three transects, crossing the shelf edge, now directly reveal this beam-wise propagation of internal tides in the Bay of Biscay. This confirms previous suggestions based on observations sampled more sparsely in space. The present observation is made by bin-wise harmonic analysis of horizontal currents, leading to the spatial resolution of barotropic and baroclinic semi-diurnal tidal and (time-averaged) residual flows. The observed baroclinic tide compares favourably to that produced by a two-dimensional numerical model. The observations reveal details of the internal tidal beam, including its spatial amplitude distribution, presence of amphidromes and direction of phase propagation. The cross-isobath structure of the along-slope barotropic mean flow shows a localized maximum near the shelf break. Over two transects it agrees in sign and magnitude with a theoretical tidally-rectified flow. The baroclinic, cross-isobath mean flow shows a strong near-bottom downwelling flow, compensated by an on-shelf directed flow in the upper part. The along-shelf mean flow displays subsurface-intensification attributed here to frictional modification of a tidally-rectified flow that is bottom-trapped due to stratification. ---Internal wave focusing revisited--- An experiment which discussed the appearance of an internal wave attractor in a uniformly-stratified, free-surface fluid (Maas et al. 1997) is revisited. This is done in order to give a more detailed and more accurate description of the underlying focusing process. Evolution of the attractor can now be quantified. For the tank with one sloping sidewall, and for the parameter regime (density stratification, forcing frequency) studied, the inverse exponential growth rate determined at several locations in the fluid turns out to be 122 seconds always. Only the start and duration of the growth differs: away from the attractor region it appears later and is of shorter duration. Here, these features are interpreted by employing a new theoretical basis that incorporates an external forcing via a surface boundary condition (an infinitesimal barotropic seiche) and that describes the solution in terms of propagating waves.

Currently, there are two main hypotheses explaining the autistic syndrome, concerning the sensory and cognitive information processing levels in the central nervous system (CNS). One possibility is that the autistic patients have a disturbance of the subcortical brain-stem sensory processing, and the other is that information processing at the higher cortical cognitive level is impaired. Brain-stem evoked potential (BEP) , middle latency evoked potential (MLEP) and event related potential (ERP) techniques could be clinically useful for the evaluation of the subcortical brain-stem function, and the cortical function. This research investigated the neurophysiological mechanisms of the processing of sensory input in 9 normal (control) and 9 autistic children, using the technique of brain-stem auditory evoked potentials (BAEPs) to gauge neural activity to click auditory stimuli. In the earliest components which occur in the 10 msec range, the wave I represents activity in the auditory nerve, and the remaining waves represent synaptic transmission upwards through the ipsilateral and contralateral lemniscal pathways. In this experiment, only 2 of 9 autistic subjects showed BAEP abnormalities, but the other autistic subjects did not show any difference as compared to the controls. If BAEP abnormalities were found, they mignt be related to organic neurological disorders. It is known that the P3b component is small in autistic children. But, some autistic subjects have deviant BAEPs, and they also have deviant middle latency auditory evoked potentials (MLAEPs). Such a neurophysiological investigation by evoked potentials (EPs) may be a clue to the understanding of a subtype of the autistic syndrome.

The Cooling Singapore project studies the urban climate of Singapore and, in particular, evaluates measures to mitigate urban heat. For this purpose, Cooling Singapore utilises a variety of tools for modelling, simulation, data processing and analysis. Some of these tools are off-the-shelf software (e.g., MATLAB, ANSYS Fluent), while others are third-party open-source software modified to meet the needs of the project (e.g., WRF), or software that has been developed in-house specifically for the purpose of the project. The resulting ecosystem of tools is thus highly diverse, requiring a diverse set of skills and operating environments in order to perform integrated studies across multiple domains. At the moment, such integrated studies are carried out in a collaborative manner involving the contributions from various researchers. The ability to carry out integrated what-if scenario analysis is important to investigate the potential impact of mitigation measures on the urban climate. This ability is not only important for researchers but also for practitioners, such as urban planning authorities for example. Manual workflow execution, involving the contributions of several researchers, represents a significant constraint. Not only is this process time-consuming, it is also prone to human error. A better approach would be to clearly specify the individual steps needed to carry out a particular what-if scenario analysis and automate (as far as possible) the entire process. This would not only reduce the amount of manual work (thus freeing researchers’ time to focus on other things) but also vastly improve the reproducibility of results and reduce the likelihood of human error. The first steps towards automated workflow execution are to analyse the workflows to better understand the various steps that are needed in order to carry out integrated studies and what-if scenario analyses. This document represents a systematic analysis of the primary workflows and their principal components in the context of the Cooling Singapore project. In particular, this document provides an overview of all principal components, as well as their input and output data. The information provided in this document is not meant to be a detailed documentation for each of the various model components. Instead, it is a system-level analysis that focuses on the flow of data from one model to another. It should also be noted that the information provided here is valid as of the time of writing. However, as the project evolves, so will the workflows and the components of the system. Technical Report, D3.1

Media facades are a prominent example of the digital augmentation of urban spaces. They denote the concept of turning the surface of a building into a large-scale urban screen. Due to their enormous size, they require interaction at a distance and they have a high level of visibility. Additionally, they are situated in a highly dynamic urban environment with rapidly changing conditions, which results in settings that are neither comparable, nor reproducible. Altogether, this makes the development of interactive media facade installations a challenging task. This thesis investigates the design of interactive installations for media facades holistically. A theoretical analysis of the design space for interactive installations for media facades is conducted to derive taxonomies to put media facade installations into context. Along with this, a set of observations and guidelines is provided to derive properties of the interaction from the technical characteristics of an interactive media facade installation. This thesis further provides three novel interaction techniques addressing the form factor and resolution of the facade, without the need for additionally instrumenting the space around the facades. The thesis contributes to the design of interactive media facade installations by providing a generalized media facade toolkit for rapid prototyping and simulating interactive media facade installations, independent of the media facade’s size, form factor, technology and underlying hardware. Die wachsende Zahl an Medienfassenden ist ein eindrucksvolles Beispiel für die digitale Erweiterung des öffentlichen Raums. Medienfassaden beschreiben die Möglichkeit, die Oberfläche eines Gebäudes in ein digitales Display zu wandeln. Ihre Größe erfordert Interaktion aus einer gewissen Distanz und führt zu einer großen Sichtbarkeit der dargestellten Inhalte. Medienfassaden-Installationen sind bedingt durch ihre dynamische Umgebung nur schwerlich vergleich- und reproduzierbar. All dies macht die Entwicklung von Installationen für Medienfassaden zu einer großen Herausforderung. Diese Arbeit beschäftigt sich mit der Entwicklung interaktiver Installationen für Medienfassaden. Es wird eine theoretische Analyse des Design-Spaces interaktiver Medienfassaden-Installationen durchgeführt und es werden Taxonomien entwickelt, die Medienfassaden-Installationen in Bezug zueinander setzen. In diesem Zusammenhang werden ausgehend von den technischen Charakteristika Eigenschaften der Interaktion erarbeitet. Zur Interaktion mit Medienfassaden werden drei neue Interaktionstechniken vorgestellt, die Form und Auflösung der Fassade berücksichtigen, ohne notwendigerweise die Umgebung der Fassade zu instrumentieren. Die Ergebnisse dieser Arbeit verbessern darüber hinaus die Entwicklung von Installationen für Medienfassaden, indem ein einheitliches Medienfassaden-Toolkit zum Rapid-Prototyping und zur Simulation interaktiver Installationen vorgestellt wird, das unabhängig von Größe und Form der Medienfassade sowie unabhängig von der verwendeten Technologie und der zugrunde liegenden Hardware ist.

The present work deals with the large-scale application of the friction welding bonding technology on timber. The investigations that are described in the following were carried out on a prototype of a welding machine that was previously developed for the purpose of this research. By means of this machine timber elements can be welded in a scale that is comparable to structural applications. Detailed experimental experience with the welding of large-sized specimens was not available at the beginning of this work. Preliminary results of initial tests on welded spruce boards indicate a correlation between the size of the sample and the occurrence of larger areas within the interface where no or only an incomplete welding result is attained. Therefore, these scaling effects were investigated in more detail in a first step. The results show that this phenomenon is associated with an internal gas pressure, which is generated at the interface during the evaporation of moisture content and other gaseous by-products. The latter result from the thermal decomposition of wooden cell wall molecules during the friction phase. It can be shown that the scaling effects can be restricted through a reduction of the moisture content or by the arrangement of gas evacuation channels at the interface, which leads to a decrease of the internal gas pressure. Subsequently the potential of the technology with regard to structural applications was estimated and evaluated by means of mechanical studies. First, investigations on the load bearing behaviour of parallel welded connections in form of double lap joints, and in particular the influence of the overlap length on the load capacity, are described. The results show that due to the extremely rigid behaviour of the bond so-called size effects occur, a phenomenon that describes a decrease in nominal strength with increasing size of a load-bearing structure. In addition to the load tests, a numerical strength prediction method is presented, which is based on a probabilistic approach and which allows for a precise prediction of the experimental results and the size effects. Furthermore, it is shown that timber boards with perpendicular fibre orientation can be welded in order to form stiff and resistant connections. Therefore, specimens of different sizes were prepared and tested for their moment transmitting capacity. In this context, a new method was introduced for the determination of a failure criterion of cross-welded joints is presented. Probabilistically determined strength values, which are based on this criterion, show good agreement with the experimental results. The non-linear relationship between the size of the specimens and the nominal strength is confirmed by the results of the numerical calculation. The results from the experiments on cross-wise welded bonds show that the strength of those connections is suitable for an application in timber construction. For this reason small scale prototypes of cross-laminated timber panels were fabricated and examined for their load bearing capacity. For this purpose the most critical load case of in-plane shear is regarded mainly since the load is transmitted only by the moment resisting behaviour of the welded bond. Based on the previously developed probabilistic strength prediction method, the load bearing capacity of the panels can be calculated numerically [...]

Experimental and analytical research is being carried out in an industrially oriented project dealing with on estimating and managing lifetime of critical structural components in energy industry. The research topics included systematic component lifetime management, lifetime of pressure bearing components, piping vibrations and integrity management, management of materials ageing, non-destructive inspection, water chemistry, oxide films and their role in service reliability and build-up of activity levels, stress corrosion cracking in Inconel welds, irradiation assisted stress corrosion cracking of core components, development of crack growth testing methods as well as the mechanisms of environmentally assisted cracking. The main results of the first project year are summarised in this report.

Deze studie, uitgevoerd in opdracht van de RVZ, tracht een inzicht te geven in de relatie tussen schaal, doelmatigheid, kwaliteit en bereikbaarheid van een aantal zorginstellingen in Nederland, op basis van een conceptueel kader, resultaten uit internationaal onderzoek en actuele en historische gegevens over zorginstellingen. Het eindrapport bevat enkele belangrijke uitkomsten. Zo blijkt dat de schaalvergroting in de zorg de afgelopen 20 jaar niet heeft geleid tot een sterke afname van de bereikbaarheid van zorginstellingen. In de ziekenhuissector is het aantal instellingen bijvoorbeeld sterk afgenomen, maar het aantal locaties (inclusief buitenpoliklinieken) juist toegenomen. Vanuit een internationaal perspectief bekeken zijn Nederlandse zorginstellingen verder aan de grote kant. Dit geldt ook vanuit het oogpunt van doelmatigheid. Doelmatigheidsargumenten kunnen derhalve geen rol spelen bij fusies tussen zorginstellingen.