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- 2018 (58) (remove)
Die folgende Studie misst in wirtschaftlicher Hinsicht den sozialen Wert und die Sozialrendite, die auf einem Teil des Fabrikgeländes von Can Batlló von 2011 bis heute entstanden sind. Um die Beiträge der Nachbarschaftsgemeinschaft in wirtschaftlicher Hinsicht zu messen, wurde eine doppelte Schätzmethode angewandt. Zum einen wurden die Beiträge der ehrenamtlichen Personen von Can Batlló in den Bereichen Verwaltung und Unterhaltung, Reinigung, Bau und Durchführung von Aktivitäten quantifiziert und bewertet. Zum anderen wurde der Wert von Can Batlló berechnet, indem ein Vergleich mit den Kosten angestellt wurde, die entstanden wären, wenn der Bau von Räumen und die Erbringung von Dienstleistungen auf Basis der Referenzpreise der jeweiligen Dienstleistung durch die Stadt erfolgt wären. Diese wirtschaftliche Bewertung der Sozialrendite wird durch die Gemeinwohlbilanz ergänzt, die von der Organisation erstellt wird.
As one of its primary objectives, Computer Graphics aims at the simulation of fabrics’ complex reflection behaviour. Characteristic surface reflectance of fabrics, such as highlights, anisotropy or retro-reflection arise the difficulty of synthesizing. This problem can be solved by using Bidirectional Texture Functions (BTFs), a 2D-texture under various light and view direction. But the acquisition of Bidirectional Texture Functions requires an expensive setup and the measurement process is very time-consuming. Moreover, the size of BTF data can range from hundreds of megabytes to several gigabytes, as a large number of high resolution pictures have to be used in any ideal cases. Furthermore, the three-dimensional textured models rendered through BTF rendering method are subject to various types of distortion during acquisition, synthesis, compression, and processing. An appropriate image quality assessment scheme is a useful tool for evaluating image processing algorithms, especially algorithms designed to leave the image visually unchanged. In this contribution, we present and conduct an investigation aimed at locating a robust threshold for downsampling BTF images without loosing perceptual quality. To this end, an experimental study on how decreasing the texture resolution influences perceived quality of the rendered images has been presented and discussed.
Next, two basic improvements to the use of BTFs for rendering are presented: firstly, the study addresses the cost of BTF acquisition by introducing a flexible low-cost step motor setup for BTF acquisition allowing to generate a high quality BTF database taken at user-defined arbitrary angles. Secondly, the number of acquired textures to the perceptual quality of renderings is adapted so that the database size is not overloaded and can fit better in memory when rendered.
Although visual attention is one of the essential attributes of HVS, it is neglected in most existing quality metrics. In this thesis an appropriate objective quality metric based on extracting visual attention regions from images and adequate investigation of the influence of visual attention on perceived image quality assessment, called Visual Attention Based Image Quality Metric (VABIQM), has been proposed. The novel metric indicates that considering visual saliency can offer significant benefits with regard to constructing objective quality metrics to predict the visible quality differences in images rendered by compressed and non-compressed BTFs and also outperforms straightforward existing image quality metrics at detecting perceivable differences.
Components of structural glazing have to meet different requirements and resist various impacts, depending on the field of application. Within an international research project of the EU innovation program Horizon 2020, special glass panes with a fluid circulating in capillaries are developed exploiting solar energy. Major influences to this glazing are UV irradiation and the fluidic contact, effecting the mechanical and optical durability of the bonding material within the glass setup. Regarding to visual requirements, acrylate adhesives and EVA films are analyzed as possible bonding materials by destructive and non-destructive testing methods. Two types of specimen are presented for obtaining the mechanical behavior and the surface appearances of the bonding material.
This dissertation is devoted to the theoretical development and experimental laboratory verification of a new damage localization method: The state projection estimation error (SP2E). This method is based on the subspace identification of mechanical structures, Krein space based H-infinity estimation and oblique projections. To explain method SP2E, several theories are discussed and laboratory experiments have been conducted and analysed.
A fundamental approach of structural dynamics is outlined first by explaining mechanical systems based on first principles. Following that, a fundamentally different approach, subspace identification, is comprehensively explained. While both theories, first principle and subspace identification based mechanical systems, may be seen as widespread methods, barely known and new techniques follow up. Therefore, the indefinite quadratic estimation theory is explained. Based on a Popov function approach, this leads to the Krein space based H-infinity theory. Subsequently, a new method for damage identification, namely SP2E, is proposed. Here, the introduction of a difference process, the analysis by its average process power and the application of oblique projections is discussed in depth.
Finally, the new method is verified in laboratory experiments. Therefore, the identification of a laboratory structure at Leipzig University of Applied Sciences is elaborated. Then structural alterations are experimentally applied, which were localized by SP2E afterwards. In the end four experimental sensitivity studies are shown and discussed. For each measurement series the structural alteration was increased, which was successfully tracked by SP2E. The experimental results are plausible and in accordance with the developed theories. By repeating these experiments, the applicability of SP2E for damage localization is experimentally proven.
Das Stapelhaus fördert das experimentelle Bauen und Forschen an der Bauhaus-Universität Weimar. Ziel ist es, schrittweise Raummodule als Arbeitsräume von Studierenden für Studierende zu bauen. Im Zusammenhang bildet sich ein kompaktes und gestapeltes Raumgefüge, das fakultätsübergreifend Raum für Experimente, Erlebnisse und Evaluierung lässt.
As part of an international research project – funded by the European Union – capillary glasses for facades are being developed exploiting storage energy by means of fluids flowing through the capillaries. To meet highest visual demands, acrylate adhesives and EVA films are tested as possible bonding materials for the glass setup. Especially non-destructive methods (visual analysis, analysis of birefringent properties and computed tomographic data) are applied to evaluate failure patterns as well as the long-term behavior considering climatic influences. The experimental investigations are presented after different loading periods, providing information of failure developments. In addition, detailed information and scientific findings on the application of computed tomographic analyses are presented.
Ziel der Arbeit war das Adsorptionsverhalten ausgewählter schutzkolloidstabilisierter Polymerpartikel mit variierender chemischer Basis im zementären System zu beschreiben und basierend auf den gewonnenen Erkenntnissen das Konkurrenzverhalten beim Angebot unterschiedlicher mineralischer Oberflächen zu klären.
Sowohl die Destabilisierung der Polymerpartikel im alkalischen Milieu, welche eine Voraussetzung für derartige Adsorptionsprozesse ist, als auch die Veränderung von Oberflächeneigenschaften verschiedener mineralischer Partikel durch Hydratations- und Ionenadsorptionsprozesse, wurden u. a. mit Hilfe elektrokinetischer Experimente erfasst. Die spektralphotometrische Erstellung von Adsorptionsisothermen ermöglichte zudem die Ermittlung der jeweiligen adsorbierten Polymermenge zu verschiedenen Zeitpunkten der frühen Hydratation. Weiterhin wurde die Polymeradsorption an Partikeln ausgewählter Zusatzstoffe in Abhängigkeit von der Ionenstärke der Flüssigphase beschrieben.
Rasterelektronenmikroskopische Untersuchungen cryo-präparierter polymermodifizierter Zementleimproben ermöglichten es außerdem deren Mikrostruktur im suspensiven Zustand zu visualisieren. Diese Aufnahmen, ebenso wie die Ergebnisse grundlegender hydratationskinetischer Untersuchungen wurden in Wechselbeziehung zu den Ergebnissen der Adsorptionsuntersuchungen gebracht.
Maßgelbliche intermolekulare und interpartikuläre Wechselwirkungen, infolge derer sich die Stabilitätsverhältnisse im Zementleim ändern und die Polymerpartikel adsorbieren sind im Wesentlichen die Desorption des Schutzkolloids von der Polymerpartikeloberfläche, die Ionisation funktioneller Gruppen der Polymerpartikel und der Schutzkolloidmakromoleküle im alkalischen Milieu und infolgedessen die Komplexbildung mit Ionen der Zementleimporenlösung. Die Auswirkungen dieser Vorgänge auf die Lösungs- und Fällungskinetik des Zementleimes wurden erfasst und mit der chemischen Zusammensetzung der polymeren Systeme korreliert.
In computer-aided design (CAD), industrial products are designed using a virtual 3D model. A CAD model typically consists of curves and surfaces in a parametric representation, in most cases, non-uniform rational B-splines (NURBS). The same representation is also used for the analysis, optimization and presentation of the model. In each phase of this process, different visualizations are required to provide an appropriate user feedback. Designers work with illustrative and realistic renderings, engineers need a
comprehensible visualization of the simulation results, and usability studies or product presentations benefit from using a 3D display. However, the interactive visualization of NURBS models and corresponding physical simulations is a challenging task because of the computational complexity and the limited graphics hardware support.
This thesis proposes four novel rendering approaches that improve the interactive visualization of CAD models and their analysis. The presented algorithms exploit latest graphics hardware capabilities to advance the state-of-the-art in terms of quality, efficiency and performance. In particular, two approaches describe the direct rendering of the parametric representation without precomputed approximations and timeconsuming pre-processing steps. New data structures and algorithms are presented for the efficient partition, classification, tessellation, and rendering of trimmed NURBS surfaces as well as the first direct isosurface ray-casting approach for NURBS-based isogeometric analysis. The other two approaches introduce the versatile concept of programmable order-independent semi-transparency for the illustrative and comprehensible visualization of depth-complex CAD models, and a novel method for the hybrid reprojection of opaque and semi-transparent image information to accelerate stereoscopic rendering. Both approaches are also applicable to standard polygonal geometry which contributes to the computer graphics and virtual reality research communities.
The evaluation is based on real-world NURBS-based models and simulation data. The results show that rendering can be performed directly on the underlying parametric representation with interactive frame rates and subpixel-precise image results. The computational costs of additional visualization effects, such as semi-transparency and stereoscopic rendering, are reduced to maintain interactive frame rates. The benefit of this performance gain was confirmed by quantitative measurements and a pilot user study.
Elitenkritik, populare Bündnisse und inklusive Solidaritär. Interview zur Debatte um Linkspopulismus
(2018)
In der aktuellen ökonomischen und politischen Krise haben Debatten um linke Strategien wieder Hochkonjunktur. Besonders kontrovers werden Vorschläge diskutiert, die einen Linkspopulismus als Alternative zum rechten politischen Projekt, zum Neoliberalismus und als Transformationsstrategie hin zu einer sozialistischen Gesellschaft propagieren. Thomas Goes und Violetta Bock haben mit ihrem Buch Ein unanständiges Angebot? Mit linkem Populismus gegen Eliten und Rechte (2017) eine programmatische Aufarbeitung existierender linker Populismuskonzepte und ihre eigene Vorstellung davon, wie ein linker Populismus gelingen kann, vorgelegt. Damit haben sie die Debatte um Linkspopulismus in Deutschland befeuert. Im Interview werden sie nach ihren Positionen und den Kontroversen um das Buch befragt. Das Interview soll als Aufschlag für eine Debatte dienen. Antworten zu den dargestellten Positionen und Bezüge zu städtischen Themen und städtischen sozialen Bewegungen sind sehr willkommen.