In dieser Arbeit wird erstmalig der Einfluss stochastischer Schwankungen auf endoreversible Modelle untersucht. Hierfür wird die Novikov-Maschine mit drei verschieden Wärmetransportgesetzen (Newton, Fourier, asymmetrisch) betrachtet. Während die maximale verrichtete Arbeit und der dazugehörige Wirkungsgrad recht einfach im Falle konstanter Wärmebadtemperaturen hergeleitet werden können, ändern sich dies, falls die Temperaturen stochastisch fluktuieren können. Im letzteren Fall muss die stochastische optimale Kontrolltheorie genutzt werden, um das Maximum der zu erwartenden Arbeit und die dazugehörige Kontrollstrategie zu ermitteln. Im Allgemeinen kann die Lösung derartiger Probleme auf eine nichtlineare, partielle Differentialgleichung, welche an eine Optimierung gekoppelt ist, zurückgeführt werden. Diese Gleichung wird stochastische Hamilton-Jacobi-Bellman-Gleichung genannt. Allerdings können, wie in dieser Arbeit dargestellt, die Berechnungen vereinfacht werden, wenn man annimmt, dass die Fluktuationen unabhängig von der betrachteten Kontrollvariablen sind. In diesem Fall zeigen analytische Betrachtungen, dass die Gleichungen für die verrichtete Arbeit and den Wirkungsgrad ihre ursprüngliche Form behalten, aber manche Terme müssen durch entsprechende Zeitmittel bzw. Erwartungswerte ersetzt werden, jeweils abhängig von der betrachteten Art der Kontrolle. Basierend auf einer Analyse der Leistungsparameter im Falle einer Gleichverteilung der heißen Temperatur der Novikov-Maschine können Schlussfolgerungen auf deren Monotonieverhalten gezogen werden. Der Vergleich verschiedener, zeitunabhängiger, symmetrischer Verteilungen führt zu einer bis dato unbekannten Erweiterung des Curzon-Ahlborn-Wirkungsgrades im Falle kleiner Schwankungen. Weiterhin wird eine Analyse einer Novikov-Maschine mit asymmetrischen Wärmetransport, bei der das Verhalten der heißen Temperatur durch einen Ornstein-Uhlenbeck-Prozess beschrieben wird, durchgeführt. Abschließend wird eine Novikov-Maschine mit Fourierscher Wärmeleitung, bei der die Dynamik der heißen Temperatur von der Kontrollvariable abhängt, betrachtet. Durch das Lösen der Hamilton-Jacobi-Bellman-Gleichung können neuartige Schlussfolgerungen gezogen werden, wie derartige Systeme optimal zu steuern sind. / In this thesis, the influence of stochastic fluctuations on the performance of endoreversible engines is investigated for the first time. For this, a Novikov-engine with three different heat transport laws (Newtonian, Fourier, asymmetric) is considered. While the maximum work output and corresponding efficiency can be deduced easily in the case of constant heat bath temperatures, this changes, if these temperatures are allowed to fluctuate stochastically. In the latter case, stochastic optimal control theory has to be used to find the maximum of the expected work output and the corresponding control policy. In general, solving such problems leads to a non-linear, partial differential equation coupled to an optimization, called the stochastic Hamilton-Jacobi-Bellman equation. However, as presented in this thesis, calculations can be simplified, if one assumes that the fluctuations are independent of the considered control variable. In this case, analytic considerations show that the equations for performance measures like work output and efficiency keep their original form, but terms have to be replaced by appropriate time averages and expectation values, depending on the considered control type. Based on an analysis of the performance measures in the case of a uniform distribution of the hot temperature of the Novikov engine, conclusions on their monotonicity behavior are drawn. The comparison of several, time independent, symmetric distributions reveals a to date unknown extension to the Curzon-Ahlborn efficiency in the case of small fluctuations. Furthermore, an analysis of a Novikov engine with asymmetric heat transport, where the behavior of the hot temperature is described by an Ornstein-Uhlenbeck process, is performed. Finally, a Novikov engine with Fourier heat transport is considered, where the dynamics of the hot temperature depends on the control variable. By solving the corresponding Hamilton-Jacobi-Bellman equation, new conclusions how to optimally control such systems are drawn.

The docotoral thesis titled 'Modeling the effects of Transient Stream Flow on Solute Dynamics in Stream Banks and Intra-meander Zones' investigates flow and solute dynamcis across surface water-groundwater interface under dynamic flow conditons through numerical simulations. The abstract of the thesis is as follows: Waters from various sources meet at the interface between streams and groundwater. Due to their different origins, these waters often have contrasting chemical signatures and therefore mixing of water at the interface may lead to significant changes in both surface and subsurface water quality. The riparian zone adjacent to the stream serves as transition region between groundwater and stream water, where complex water and solute mixing and transport processes occur. Predicting the direction and the magnitude of solute exchanges and the extent of transformations within the riparian zone is challenging due to the varying hydrologic and chemical conditions as well as heterogeneous morphological features which result in complex, three-dimensional flow patterns. The direction of water flow and solute transport in the riparian zone typically varies over time as a result of fluctuating stream water and groundwater levels. Particularly, increasing groundwater levels can mobilize solutes from the unsaturated zone which can be subsequently transported into the stream. Such complex, spatially and temporally varying processes are hard to capture with field observations alone and therefore modeling approaches are required to predict the system behavior as well as to understand the role of individual factors. In this thesis, we investigate the inter-connectivity of streamthe s and adjacent riparia zones in the context of water and solute exchanges both laterally for bank storage and longitudinally for hyporheic flow through meander bends. Using numerical modeling, the transient effect of stream flow events on solute transport and transformation within the initially unsaturated part of stream banks and meander bends have been simulated using a systematic set of hydrological, chemical and morphological scenarios. A two dimensional variably saturated media groundwater modeling set up was used to explore solute dynamics during bank flows. We simulated exchanges between stream and adjacent riparian zone driven by stream stage fluctuations during stream discharge events. To elucidate the effect of magnitude and duration of discharge events, we developed a number of single discharge event scenarios with systematically varying peak heights and event duration. The dominant solute layer was represented by applying high solute concentration in upper unsaturated riparian zone profile. Simulated results show that bank flows generated by high stream flow events can trigger solute mobilization in near stream riparian soils and subsequently export significant amounts of solutes into the stream. The timing and amount of solute export is linked to the shape of the discharge event. Higher peaks and increased duration significantly enhance solute export, however, peak height is found to be the dominant control for overall lateral mass export. The mobilized solutes are transported towards the stream in two stages (1) by return flow of stream water that was stored in the riparian zone during the event and (2) by vertical movement to the groundwater under gravity drainage from the unsaturated parts of the riparian zone, which lasts for significantly longer time (> 400 days) resulting in a theoretically long tailing of bank outflows and solute mass outfluxes. Our bank flow simulations demonstrate that strong stream discharge events are likely to mobilize and export significant quantity of solutes from near stream riparian zones into the stream. Furthermore, the impact of short-term stream discharge variations on solute exchange may sustain for long times after the flow event. Meanders are prominent morphological features of stream systems which exhibit unique hydrodynamics. The water surface elevation difference across the inner bank of a meander induces lateral hyporheic exchange flow through the intrameander region, leading to solute transport and reactions within intra-meander region. We examine the impact of different meander geometries on the intra-meander hyporheic flow field and solute mobilization under both steady-state and transient flow conditions. In order to explore the impact of meander morphology on intrameander flow, a number of theoretical meander shape scenarios, representing various meander evolution stages, ranging from a typical initial to advanced stage (near cut off ) meander were developed. Three dimensional steady-state numerical groundwater flow simulations including the unsaturated zone were performed for the intra-meander region for all meander scenarios. The meandering stream was implemented in the model by adjusting the top layers of the modeling domain to the streambed elevation. Residence times for the intra-meander region were computed by advective particle tracking across the inner bank of meander. Selected steady state cases were extended to transient flow simulations to evaluate the impact of stream discharge events on the temporal behavior of the water exchange and solute transport in the intra-meander region. Transient hydraulic heads obtained from the surface water model were applied as transient head boundary conditions to the streambed cells of the groundwater model. Similar to the bank storage case, a high concentration of solute (carbon source) representing the dominant solute layer in the riparian profile was added in the unsaturated zone to evaluate the effect of stream flow event on mobilization and transport from the unsaturated part of intrameander region. Additionally, potential chemical reactions of aerobic respiration by the entry of oxygen rich surface water into subsurface as well denitrification due to stream and groundwater borne nitrates were also simulated. The results indicate that intra-meander mean residence times ranging from 18 to 61 days are influenced by meander geometry, as well as the size of the intra-meander area. We found that, intra-meander hydraulic gradient is the major control of RTs. In general, larger intra-meander areas lead to longer flow paths and higher mean intra-meander residence times (MRTs), whereas increased meander sinuosity results in shorter MRTs. The vertical extent of hyporheic flow paths generally decreases with increasing sinuosity. Transient modeling of hyporheic flow through meanders reveals that large stream flow events mobilize solutes from the unsaturated portion of intra-meander region leading to consequent transport into the stream via hyporheic flow. Advective solute transport dominates during the flow event; however significant amount of carbon is also consumed by aerobic respiration and denitrification. These reactions continue after the flow events depending upon the availability of carbon source. The thesis demonstrates that bank flows and intra-meander hyporheic exchange flows trigger solute mobilization from the dominant solute source layers in the RZ. Stream flow events driven water table fluctuations in the stream bank and in the intra-meander region transport substantial amount of solutes from the unsaturated RZ into the stream and therefore have significant potential to alter stream water quality.:Declaration Abstract Zusammenfassung 1 General Introduction 1.1 Background and Motivation 1.2 Hydrology and Riparian zones 1.2.1 Transport processes driven by fluctuation in riparian water table depth 1.2.1.1 Upland control 1.2.1.2 Stream control 1.2.2 Biochemical Transformations within the Riparian Zone 1.3 Types and scales of stream-riparian exchange 1.3.1 Hyporheic Exchange 1.3.1.1 Small Scale Vertical HEF 1.3.1.2 Large Scale lateral HEF 1.3.2 Bank Storage 1.4 Methods for estimation of GW-SW exchanges 1.4.1 Field Methods 1.4.1.1 Direct measurement of water flux 1.4.1.2 Tracer based Methods 1.4.2 Modeling Methods 1.4.2.1 Transient storage models 1.4.2.2 Physically based models 1.5 Research gaps and need 1.6 Objectives of the research 1.7 Thesis Outline 2 Flow and Transport Dynamics during Bank Flows 2.1 Introduction 2.2 Methods 2.2.1 Concept and modeling setup 2.2.2 Numerical Model 2.2.3 Stream discharge events 2.2.4 Model results evaluation 2.3 Results and discussion 2.3.1 Response of water and solute exchange to stream discharge events 2.3.1.1 Water exchange time scales 2.3.1.2 Stream water solute concentration 2.3.2 Solute mobilization within the riparian zone 2.3.3 Influence of peak height and event duration on solute mass export towards the stream 2.3.4 Effects of event hydrograph shape on stream water solute concentration 2.3.5 Model limitations and future studies 2.4 Summary and Conclusions Appendix 2 3 Flow and Transport Dynamics within Intra-Meander Zone 3.1 Introduction 3.2 Methods 3.2.1 Meander Shape Scenarios 3.2.2 Surface Water Simulations 3.2.3 3D Groundwater Flow Simulations with Modeling code MIN3P 3.2.3.1 Steady Flow Simulations 3.2.3.2 Stream flow event and Solute Mobilization Set-up 3.2.4 Reactive Transport 3.3 Results and Discussion 3.3.1 Groundwater heads and flow paths in the saturated intrameander zone 3.3.1.1 Groundwater heads 3.3.1.2 Flow paths and isochrones 3.3.1.3 Vertical extent of flow paths 3.3.2 Intra-Meander Residence Time Distribution 3.3.3 Factors affecting intra-meander flow and residence times 3.3.3.1 intra-meander hydraulic gradient 3.3.3.2 Maximum penetration depth 3.3.3.3 Meander sinuosity 3.3.3.4 intra-meander area (A) 3.3.4 Influence of Discharge Event on intra-meander Flow and Solute Transport 3.3.4.1 Spatial distribution of groundwater head and solute concentration 3.3.4.2 Time scales of intra-meander groundwater heads and solute transport 3.3.4.3 Solute export during stream discharge event 3.3.5 Intra-meander reactive transport during stream discharge event 3.3.5.1 Impact of stream discharge on aerobic respiration and denitrification 3.3.5.2 DOC mass removal during stream discharge event 3.4 Summary and Conclusions Appendix 3 4 General Summary and Conclusions 4.1 Summary 4.2 Conclusions 4.2.1 Flow and Transport Dynamics in Near Stream Riparian Zone (Bank Flows) 4.2.2 Flow and Transport Dynamics within Intra-Meander Zone 4.3 Model Limitations and Future Studies Bibliography Acknowledgement

In this thesis, we propose many developments in the context of Structural Similarity. We address both node (local) similarity and graph (global) similarity. Concerning node similarity, we focus on improving the diffusive process leading to compute this similarity (e.g. Commute Times) by means of modifying or rewiring the structure of the graph (Graph Densification), although some advances in Laplacian-based ranking are also included in this document. Graph Densification is a particular case of what we call graph rewiring, i.e. a novel field (similar to image processing) where input graphs are rewired to be better conditioned for the subsequent pattern recognition tasks (e.g. clustering). In the thesis, we contribute with an scalable an effective method driven by Dirichlet processes. We propose both a completely unsupervised and a semi-supervised approach for Dirichlet densification. We also contribute with new random walkers (Return Random Walks) that are useful structural filters as well as asymmetry detectors in directed brain networks used to make early predictions of Alzheimer's disease (AD). Graph similarity is addressed by means of designing structural information channels as a means of measuring the Mutual Information between graphs. To this end, we first embed the graphs by means of Commute Times. Commute times embeddings have good properties for Delaunay triangulations (the typical representation for Graph Matching in computer vision). This means that these embeddings can act as encoders in the channel as well as decoders (since they are invertible). Consequently, structural noise can be modelled by the deformation introduced in one of the manifolds to fit the other one. This methodology leads to a very high discriminative similarity measure, since the Mutual Information is measured on the manifolds (vectorial domain) through copulas and bypass entropy estimators. This is consistent with the methodology of decoupling the measurement of graph similarity in two steps: a) linearizing the Quadratic Assignment Problem (QAP) by means of the embedding trick, and b) measuring similarity in vector spaces. The QAP problem is also investigated in this thesis. More precisely, we analyze the behaviour of $m$-best Graph Matching methods. These methods usually start by a couple of best solutions and then expand locally the search space by excluding previous clamped variables. The next variable to clamp is usually selected randomly, but we show that this reduces the performance when structural noise arises (outliers). Alternatively, we propose several heuristics for spanning the search space and evaluate all of them, showing that they are usually better than random selection. These heuristics are particularly interesting because they exploit the structure of the affinity matrix. Efficiency is improved as well. Concerning the application domains explored in this thesis we focus on object recognition (graph similarity), clustering (rewiring), compression/decompression of graphs (links with Extremal Graph Theory), 3D shape simplification (sparsification) and early prediction of AD. / Ministerio de Economía, Industria y Competitividad (Referencia TIN2012-32839 BES-2013-064482)

This dissertation is interested in what kind of self and techniques of resistance are acquired in order to be a revolutionary in the contemporary West. While I was conducting an ethnographic research between 2008 - 2015 following young activists from Germany in urban spaces of demonstrations, riots, direct actions, jails, the Internet, universities, housing projects, parent's homes in Germany as well as during solidarity trips to Mexico, Argentina, Israel/Palestine, Denmark or Italy, it was discovered that a concept of political versatility may be helpful here. Young revolutionaries are what I call revolutionary amoebas. Revolutionary amoebas acquire capacities to discuss at universities or public debates, write texts, talk, but they manage to argue beyond the discourse by throwing stones or burning cars in riots, organizing direct actions, smashing corporate properties, beating neo­nazis, attacking ultra­nationalists, or actively defending themselves against the police. As citizens of advanced liberal democracy, they enter public discussions of contested opinions, persuade people with their critical arguments and a few of them even vote, but they as well explore the political terrain considered illegal. Many of them know how to get funded from the state, The EU,...

Relying on framing theory, this study used The New York Times to explore how Chinese news was depicted before, during and after the Beijing Summer Olympics. The research regarding how the Chinese government tried to leverage the Olympics to enhance its image is often deliberated. However, there have only been a 3 few studies on the evaluation of the effects the 2008 Beijing Summer Olympic Games had on the image of China, as depicted by The New York Times. This study generated an understanding of the impact the presentations of The New York Times had on the soft power used by China through the Beijing Summer Olympic Games. The study examined how the 2008 Beijing Summer Olympics were associated with the depiction of Chinese news in The New York Times during the pre-, mid-, and post-Olympics years. Specifically, world and business sections within The New York Times were mainly influenced by the effects of the 2008 Beijing Summer Olympics. In addition, there were no direct associations found between the 2008 Beijing Summer Olympics and how China was depicted photographically in The New York Times. In terms of the above factors; this study showed that China's national image did not improve in the New York Times after the 2008 Bejing Summer Olympic Games.

Předložená disertační práce se zabývá popisem charakteru optimální strategie řízení pro elektrický vlak a výpočtem přepínacích okamžiků mezi jednotlivými optimálními jízdními režimy pro standardní typy odporové funkce. S využitím Pontrjaginova principu a souvisejících nástrojů teorie optimálního řízení odvodíme optimální strategii řízení a rovnice pro výpočet přepínacích okamžiků včetně odpovídajících rychlostních profilů. Kromě základního tvaru úlohy o energeticky optimální jízdě vlaku budeme uvažovat i její modifikace zahrnující globální rychlostní omezení, sklon trati i časově-energeticky optimální řízení vlaku. Navíc uvedeme i analýzu řešení s využitím teorie nelineární parametrické optimalizace. Důraz je kladen na exaktní tvar řešení s minimálním využitím numerických metod.

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Es ist ein politisch erklärtes Ziel, den Ausstoß von klimaschädlichen Treibhausgasen weltweit zu verringern. Eine wesentliche Stellschraube im Gebiet des Bauwesens stellt hierbei die Einsparung von Energien zur Raumkonditionierung dar. Diese wird unter anderem über das Lüftungskonzept beeinflusst. Die Belüftung von Gebäuden ist zwingend notwendig, um die Emissionen der Baustoffe und die der Menschen, beispielsweise ihren CO2-Ausstoß über die Atmung, abzuführen und der Schimmelbildung vorzubeugen. Erfolgt die Belüftung über öffenbare Fenster – natürliche Lüftung – wird so allerdings energetisch aufwändig temperierte Raumluft mit untemperierter Außenluft ausgetauscht. Daraus können Wärmeverluste und thermisches Unbehagen resultieren. Energieeffiziente Technologien sind ventilatorgestützte Lüftungssysteme mit Wärmerückgewinnung. Doch nicht für alle Gebäudekonzepte und Nutzer stellen diese Lüftungskonzepte einen hohen Nutzerkomfort dar. Korrelationen zwischen Gebäuden mit ventilatorgestützten Lüftungsystemen und dem Sick-Building-Syndrom sind in der Literatur beschrieben, während hier für natürliche Lüftungskonzepte keine Korrelation besteht. Stattdessen wird in Nutzerbefragungen der natürlichen Lüftung eine hohe Akzeptanz zugeschrieben. Mit elektrisch angetriebenen Fenstern kann die natürliche Lüftung nutzerunabhängig gesteuert und so Wärmeverluste und thermisches Unbehagen kontrolliert werden. Bisher sind die Auslegungen solcher kontrollierten natürlichen Lüftungskonzepte noch sehr planungsintensiv. Das Ziel der Arbeit ist es, für Büro- und Verwaltungsgebäude Öffnungs- und Schließsignale einer kontrollierten natürlichen Lüftung zu geben. Diese zeichnen sich darüber aus, dass sie ein gesundes Raumklima, eine hohe Nutzerbehaglichkeit und Energieeffizienz über den Jahresverlauf schaffen und auf ihre Robustheit gegenüber Änderungen von Gebäuderandbedingungen überprüft sind. Für das Ziel wird ein über CO2- und Temperatursensoren gesteuertes Fenstersystem mittels dynamisch thermischer Gebäudesimulationen in vier Varianten von Schließsignalen auf thermische Behaglichkeit und Energiebedarf untersucht. Die Grundlage dazu stellt die bezüglich Entwurf, Konstruktion und Nutzung allgemeingültige Entwicklung eines Büroraums dar. Der Büroraum wird im Simulationsmodell abgebildet und in Realität errichtet. Die Kombination von Simulationsmodell und realem, als experimentellem Teststand ausgeführtem Büroraum ermöglicht verifizierte Ergebnisse. So werden vier Berechnungsmodelle für Luftvolumenströme von Fenstern über den Teststand verifiziert. Dazu dienen Luftwechselmessungen nach der Konstantinjektionsmethode an 173 Fensteröffnungen für fünf Außentemperatur- und elf Windgeschwindigkeitsbereiche. Das Berechnungsmodell nach DIN EN 16798-7 zeigt sich als realitätsnah. Da dieses Berechnungsmodell nicht im Gebäudesimulationsprogramm implementiert ist, wird eine Methode zur Implementierung entwickelt. Über das entwickelte Simulationsmodell zeigt sich, dass eine kombinierte CO2- und temperaturgesteuerte kontrollierte natürliche Lüftung nur zweimal im Jahr ihre Grenzwerte zur Fensteröffnung und -schließung variieren muss, um ganzjährig eine hohe Energieeffizienz und Nutzerbehaglichkeit zu schaffen. Die Schließsignale des sensorgesteuerten Fenstersystems werden in eine Zeitsteuerung überführt. Es zeigt sich, dass für die kühlen Monate jede Öffnung mit identischer Dauer angesetzt werden darf. In wärmeren Monaten muss die Öffnungsdauer in Abhängigkeit der Außentemperatur angepasst werden, so dass eine Zeitsteuerung mit einer Außentemperaturmessung gekoppelt werden muss. Die Ergebnisse zeigen, dass über eine Variation der Schließsignale einer kontrollierten natürlichen Lüftung die Energieeffizienz und die thermische Behaglichkeit wesentlich gesteigert werden und dass selbst bei geringen Windgeschwindigkeiten und Temperaturdifferenzen die Raumluftqualität stets gewährleistet ist. Für nahezu alle Standorte in Deutschland kann die kontrollierte natürliche Lüftung so den Kühlbedarf der untersuchten Büroräume eliminieren, ohne in einer sommerlichen Überhitzung der Räume zu resultieren. Die entwickelten und bezüglich Raumluftqualität und thermischer Behaglichkeit charakterisierten Sensor- und Zeitsteuerungen tragen dazu bei, die kontrollierte natürliche Lüftung als wartungsarme, technikreduzierte Alternative zu der ventilatorgestützten Lüftung zu etablieren.:1 Einleitung 2 Natürliche Lüftung 3 Kontrollmöglichkeiten der natürlichen Lüftung 4 Entwicklung der Untersuchungsmodelle 5 Voruntersuchungen 6 Sensorsteuerung für den Basisraum 7 Zeitsteuerung für den Basisraum 8 Übertragung auf unterschiedliche Gebäuderandbedingungen 9 Diskussion und Empfehlungen 10 Zusammenfassung und Ausblick 11 Literatur 12 Abbildungsnachweis 13 Bezeichnungen 14 Anhang / It is a politically declared goal to reduce the emission of climate-damaging greenhouse gases worldwide. To support this goal by the building industry a key driver is the saving of energy for room conditioning. Among other factors, this is influenced by the ventilation concept. Also the ventilation of buildings is absolutely necessary in order to remove the emissions of the building materials and those of the people, for example their CO2 emissions through breathing as well as to prevent mould. However, if ventilation is carried out via openable windows - natural ventilation - then energetically expensive tempered room air is exchanged with cold outside air. This could result in heat loss and thermal discomfort. Mechanical ventilation systems with heat recovery are energy-efficient technologies. However, these ventilation concepts do not represent a high level of user comfort for all building concepts and users. Correlations between buildings with mechanical ventilation systems and sick building syndrome are described in the literature, while there is no such correlation for natural ventilation concepts. Instead, a high level of acceptance is attributed to it in user surveys. With electrically driven and controlled windows, natural ventilation can be controlled independently from the user, thus minimizing heat loss and thermal discomfort. So far, the design of such controlled natural ventilation concepts is still very planning-intensive. The aim of this work is to provide opening and closing signals for controlled natural ventilation in office buildings. These are characterized for their capability to create a high indoor air quality, high user comfort and high energy efficiency over the course of the year and are tested for their robustness against changes in building characteristics. To achieve this goal, a window system controlled by CO2 and temperature sensors is examined for its impact on thermal comfort and energy demand by means of building simulation tools with four variants of closing signals. As a basis for this examination an office room is utilized that conforms to the current standards in terms of design, construction and use. The office space is transferred to a simulation model and constructed in reality. The combination of the simulation model and the real office space, which is designed as an experimental test rig, enables verified results. Thus, four calculation models for air flow volumes of windows are verified via the test rig. Air exchange measurements according to the constant injection method on 173 window openings for five outdoor temperature and eleven wind speed ranges are used for this purpose. The calculation model according to DIN EN 16798-7 proves to be close to reality. Since this calculation model is not implemented in the building simulation program, a method for its implementation is developed. Using the developed simulation model, it is shown that a combined CO2- and temperature-controlled natural ventilation creates a high energy efficiency and user comfort throughout the year by varying its limit values for window opening and closing only twice a year. The closing signals of the sensor controlled window system are transferred to a time control system. It turns out that for the cold months, each opening could be set to the same opening time. In warmer months, the opening time must be adjusted depending on the outside temperature. Thus, a time control should be coupled with an outside air temperature measurement. The results show that by varying the closing signals of a controlled natural ventilation system, the energy efficiency and thermal comfort is significantly increased and that a high indoor air quality is always guaranteed even at low wind speeds and low temperature differences. For almost all locations in Germany, controlled natural ventilation can thus eliminate the cooling requirements in the office spaces studied without overheating in the summer. The developed sensor and time control systems are characterized by high indoor air quality and good thermal comfort. Thus, these systems are a contribution to promote controlled natural ventilation as a low-maintenance and technically reduced alternative to mechanical ventilation.:1 Einleitung 2 Natürliche Lüftung 3 Kontrollmöglichkeiten der natürlichen Lüftung 4 Entwicklung der Untersuchungsmodelle 5 Voruntersuchungen 6 Sensorsteuerung für den Basisraum 7 Zeitsteuerung für den Basisraum 8 Übertragung auf unterschiedliche Gebäuderandbedingungen 9 Diskussion und Empfehlungen 10 Zusammenfassung und Ausblick 11 Literatur 12 Abbildungsnachweis 13 Bezeichnungen 14 Anhang

This dissertation is interested in what kind of self and techniques of resistance are acquired in order to be a revolutionary in the contemporary West. While I was conducting an ethnographic research between 2008 - 2015 following young activists from Germany in urban spaces of demonstrations, riots, direct actions, jails, the Internet, universities, housing projects, parent's homes in Germany as well as during solidarity trips to Mexico, Argentina, Israel/Palestine, Denmark or Italy, it was discovered that a concept of political versatility may be helpful here. Young revolutionaries are what I call revolutionary amoebas. Revolutionary amoebas acquire capacities to discuss at universities or public debates, write texts, talk, but they manage to argue beyond the discourse by throwing stones or burning cars in riots, organizing direct actions, smashing corporate properties, beating neo­nazis, attacking ultra­nationalists, or actively defending themselves against the police. As citizens of advanced liberal democracy, they enter public discussions of contested opinions, persuade people with their critical arguments and a few of them even vote, but they as well explore the political terrain considered illegal. Many of them know how to get funded from the state, The EU,...

La recherche d'un appui extérieur n'est pas un aspect étranger à l'histoire de la résistance algérienne. L'action extérieure s'est produite en trois phases différentes mais continues. La première qui débute avec la résistance d'Abdelkader se termine autour de la fin de la Première Guerre mondiale. La deuxième se situe entre les deux grandes guerres. Tandis que la dernière débute pendant la Deuxième Guerre mondiale pour se poursuivre jusqu'à l'indépendance, avec un net renforcement à partir de 1954. En effet, à partir de cette date les nationalistes algériens ont attaché une égale importance à l'action militaire et diplomatique soutenue constamment par les divers moyens et méthodes d'information. Ce qui explique l'intérêt qu'ils ont apporté à la presse et à l'opinion publique occidentale dans leur affrontement avec la France. À travers l'analyse descriptive des événements et l'analyse de contenu du New York Times, je veux identifier les stratégies adoptées par les nationalistes algériens en vue de l'augmentation des sensibilités de l'opinion américaine envers la révolution algérienne. Ainsi, l'analyse de contenu m'a permis d'identifier la perception qu'avait ce journal envers le conflit algérien. L'analyse quantitative, un élément important dans l'analyse de contenu, m'a permis de mesurer l'intérêt considérable que le journal a porté au conflit algérien, à travers la publication d'un nombre impressionnant de dépêches d'aspects factuels, d'articles d'analyse et d'information, et d'éditoriaux. Tandis qu'à travers l'analyse qualitative de la couverture du journal du conflit, j'ai pu constater le lien étroit que le journal n'a cessé d'établir entre les enjeux de la guerre froide et le conflit algérien. L'ambiguïté dans la perception du conflit est partagée avec le gouvernement américain. Pour l'un comme pour l'autre la conception de la défense de l'intérêt national américain a pris le pas sur les traditions anticoloniales américaines. / Québec Université Laval, Bibliothèque 2013