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Modeling and temperature control of a moving substrate
No full textThis paper describes the development of a control system for an industrial heating application. In this process a moving substrate is passing through a heating zone with variable speed. Heat is applied by hot air to the substrate with the air flow rate being the manipulated variable. The aim is to control the substrate’s temperature at a specific location after passing the heating zone. First, a model is derived for a point attached to the moving substrate. This is modified to reflect the temperature of the moving substrate at the specified location. In order to regulate the temperature a nonlinear model predictive control approach is applied using an implicit Euler scheme to integrate the model and an augmented gradient based optimization approach. The performance of the controller has been validated both by simulations and experiments on the physical plant. The respective results are presented in this paper
Real-Time Range Query Approximation by Means of Adaptive Quad Streaming
No full textContinuous range queries are a common means to handle mobile clients in high-density areas. Most existing approaches focus on settings in which the range queries for location-based services are mostly static whereas the mobile clients in the ranges move. We focus on a category called Dynamic Real-Time Range Queries (DRRQ) assuming that both, clients requested by the query and the inquirers, are mobile. In consequence, the query parameters results continuously change. This leads to two requirements: the ability to deal with an arbitrary high number of mobile nodes (scalability) and the real-time delivery of range query results. In this paper we present the highly decentralized solution Adaptive Quad Streaming (AQS) for the requirements of DRRQs. AQS approximates the query results in favor of a controlled real-time delivery and guaranteed scalability. While prior works commonly optimizes data structures on servers, we use AQS to focus on a highly distributed cell structure without data structures automatically adapting to changing client distributions. Instead of the commonly used request-response approach, we apply a lightweight streaming method in which no bidirectional communication and no storage or maintenance of queries are required at all
Urban components under Article 6 of the Paris Agreement
No full textUrban areas cause over 70% of direct and indirect CO2-emissions worldwide. To achieve the internationally agreed goal of limiting the global temperature increase to 1.5 to 2 ° C, considerable efforts to reduce emissions in cities are required. Mobilizing significant greenhouse gas reductions in cities is, however, a major challenge due to their very heterogeneous structures and a large number of small and varied emission sources (e.g. traffic, buildings). In addition, the organisational structures of urban emission sources are much more diverse than those of e.g. major industrial point sources. A general challenge for responsible decision-makers and institutions is that they have limited access to investment capital to implement large-scale measures to reduce greenhouse gas emissions.
Carbon market mechanisms under Article 6 of the Paris Agreement can offer new opportunities for the mobilisation of large-scale emission reduction measures and policies. This research project first examined the prevalence and experience of urban reduction projects within the framework of the Clean Development Mechanism (CDM), Nationally Appropriate Mitigation Actions (NAMAs) and Transformative Actions Programs (TAP). Building on this, various conceptual approaches to the implementation of Art. 6 in cities were developed. In order to take appropriate account of the different national structures and framework conditions, a “menu approach” with uniform principles and standards is proposed.
In addition, the study examines approaches to determine the additionality of urban mitigation activities and discusses various financing options.Städtische Gebiete verursachen über 70% der direkten und indirekten CO2-Emissionen weltweit. Um das international vereinbarte Ziel zu erreichen, den globalen Temperaturanstieg auf 1,5 bis 2 °C zu begrenzen, sind erhebliche Anstrengungen zur Emissionsreduktion in Städten erforderlich. Die Mobilisierung signifikanter Treibhausgasminderungen in Städten ist jedoch aufgrund ihrer sehr heterogenen Strukturen und einer großen Anzahl kleiner, unterschiedlicher Emissionsquellen (z. B. Verkehr, Gebäude) eine große Herausforderung. Darüber hinaus sind die Organisationsstrukturen städtischer Emissionsquellen viel vielfältiger als die von z.B. großen industriellen Punktquellen. Eine weitere Herausforderung für verantwortliche Entscheidungsträger und Institutionen ist, dass sie nur eingeschränkten Zugang zu Investitionskapital haben, um großskalierte Maßnahmen zur Reduktion von Treibhausgasminderungen umzusetzen.
Kohlenstoffmarktmechanismen nach Artikel 6 des Pariser Abkommens können neue Chancen für die Mobilisierung von großangelegten Emissionsminderungs-Maßnahmen und Politiken darstellen. Das vorliegende Forschungsprojekt hat zunächst die Prävalenz und Erfahrungen städtischer Minderungsprojekte im Rahmen des Clean Development Mechanism (CDM), von Nationally Appropriate Mitigation Actions (NAMAs) sowie von Transformative Actions Programs (TAP) untersucht. Darauf aufbauend wurden verschiedene konzeptionelle Ansätze zur Umsetzung von Artikel 6 in Städten erarbeitet. Um die unterschiedlichen nationalen Strukturen und Rahmenbedingungen angemessen berücksichtigen zu können, wird ein „Menüansatz“ mit einheitlichen Prinzipien und Standards vorgeschlagen.
Darüber hinaus untersucht die Studie Ansätze zur Bestimmung der Zusätzlichkeit urbaner Minderungsaktivitäten und diskutiert verschiedene Finanzierungsoptionen
Real-Time Gesture Detection Based on Machine Learning Classification of Continuous Wave Radar Signals
No full textClassical signal processing methodologies have been infiltrated by machine learning (ML) approaches for a long time, where the ML approaches are in particular applied when it comes to gesture recognition. In this paper, we investigate naïve gesture recognition methodologies and compare classical and novel machine learning (nML) algorithms. The considered gestures are simple human gestures such as swiping a hand or kicking with a foot. For the sake of comparability, the algorithms are assessed with respect to their true positive rate (TPR), false-positive rate (FPR), their real-time capability together with the required computational power, and their implementability on low-cost hardware. Two different data sets are utilized separately for the training process of the ML algorithms, where both have been recorded by making use of low-cost radar hardware. The results show that all ML approaches are superior to naïve gesture recognition methodologies, e.g., threshold detection. ML algorithms allow almost assured gesture detection. However, our primary contribution is a design approach for scalable neural networks (NNs) that allow such gesture recognition algorithms to be executable on low-cost microcontroller units (MCUs)
Difficult SQLi Code Patterns for Static Code Analysis Tools
No full textWe compared vulnerable and fixed versions of the source code of 50 different PHP open source projects based on CVE reports for SQL injection vulnerabilities. We scanned the source code with commercial and open source tools for static code analysis. Our results show that five current state-of-the-art tools have issues correctly marking vulnerable and safe code. We identify 25 code patterns that are not detected as a vulnerability by at least one of the tools and 6 code patterns that are mistakenly reported as a vulnerability that cannot be confirmed by manual code inspection. Knowledge of the patterns could help vendors of static code analysis tools, and software developers could be instructed to avoid patterns that confuse automated tools
Montgomery Reduction for Gaussian Integers
Get PDFModular arithmetic over integers is required for many cryptography systems. Montgomeryreduction is an efficient algorithm for the modulo reduction after a multiplication. Typically, Mont-gomery reduction is used for rings of ordinary integers. In contrast, we investigate the modularreduction over rings of Gaussian integers. Gaussian integers are complex numbers where the real andimaginary parts are integers. Rings over Gaussian integers are isomorphic to ordinary integer rings.In this work, we show that Montgomery reduction can be applied to Gaussian integer rings. Twoalgorithms for the precision reduction are presented. We demonstrate that the proposed Montgomeryreduction enables an efficient Gaussian integer arithmetic that is suitable for elliptic curve cryptogra-phy. In particular, we consider the elliptic curve point multiplication according to the randomizedinitial point method which is protected against side-channel attacks. The implementation of thisprotected point multiplication is significantly faster than comparable algorithms over ordinary primefields
Development of a sustainable structural concept for the Maun Science Park
Get PDFIn Maun, Botswana, a self-sufficient, sustainable and future-oriented district will be created, the Maun Science Park. Within this project, several 5-8 storey smart homes shall be built in sustainable construction. The aim of this thesis is to develop a sustainable structural concept for those homes of the Maun Science Park. In a first step, the general basics for tall building structures and sustainable construction were established. Based on those fundamentals, criteria for the structural requirements, the ecological as well as the social sustainability of a structural design could be defined. Subsequently, four structural systems were drafted: a concrete core structure, a steel shear frame structure, a rammed earth shear wall structure and a wooden diagrid structure. In addition to the pre-dimensioning of the systems, a life cycle assessment was set up to evaluate the ecological sustainability of the designs. With the help of a utility value analysis, the wooden diagrid structure was determined as the preferred variant. The comparison of the designs also allows to draw general conclusions for the development of sustainable tall building structures. The results of the life cycle assessment show the advantage of wood as an ecological building material over industrially manufactured building materials, such as steel and concrete. Whereas rammed earth, a likewise ecological building material, is not convincing due to its low strength. In general, a balance is created in the life cycle assessment between ecological and industrially manufactured products in regard of strength and environmental impact. In terms of social sustainability, the design of the structure system can significantly influence the flexibility and use of local resources. However, due to the diversity of sustainable construction, the development of a structural system should be linked to an overarching sustainability concept that takes architecture and stakeholders into account.In Maun, Botswana soll ein autarker, nachhaltiger und zukunftsorientierter Stadtteil entstehen, der Maun Science Park. Im Rahmen dieses Projektes sollen mehreren 5-8 stöckige smart homes in nachhaltiger Bauweise errichtet werden. Ziel der vorliegenden Arbeit ist es, ein nachhaltigen Tragwerkskonzept für die Gebäude des Maun Science Park zu entwickeln. Um dies zu erreichen wurden zu Beginn die allgemeinen Grundlagen für Hochhaustragwerke und zum Thema Nachhaltiges Bauen ermittelt. Basierend auf diesen Grundlagen konnten Kriterien für die strukturellen Anforderungen, die ökologische sowie die soziale Nachhaltigkeit des Tragwerkentwurfes definiert werden. Anschließend wurden vier Tragwerkssysteme entwickelt: eine Kerntragwerk aus Beton, eine ausgesteifte Stahlrahmen Konstruktion, eine Schubwand Konstruktion aus Stampflehm und eine Röhrentragwerk aus Holz. Hierbei wurde neben der Vorbemessung für die Tragwerke, eine Ökobilanz zur Bewertung der ökologischen Nachhaltigkeit der Entwürfe aufgestellt. Mithilfe einer Nutzwertanalyse konnte das Röhrentragwerk aus Holz als Vorzugsvariante ermittelt werden. Der Vergleich der Entwürfe lässt darüber hinaus allgemeine Schlüsse für die Entwicklung nachhaltiger Hochhaustragwerke zu. Die Ergebnisse der Ökobilanz zeigen den Vorteil von Holz als ökologisches Baumaterial im Gegensatz zu industriell gefertigten Bauprodukten wie Stahl und Beton. Stampflehm, ebenfalls ein ökologisches Baumaterial, kann hingegen aufgrund seiner geringen Festigkeit nicht überzeugen. Generell entsteht in der Ökobilanz ein Ausgleich zwischen ökologischen und industriell gefertigten Produkten in Bezug auf Festigkeit und Umweltauswirkungen. Im Hinblick auf die soziale Nachhaltigkeit kann die Gestaltung des Tragwerkes maßgeblich die Flexibilität und den Einsatz von lokalen Ressourcen beeinflussen. Aufgrund der Vielfältigkeit des Nachhaltigen Bauens sollte sich die Entwicklung eines Tragwerks an einem übergeordneten Nachhaltigkeitskonzept, welches Architektur und Zielgruppen berücksichtigt, orientieren
Bepreisung von Treibhausgasemissionen: Fair - Effizient - Sozialverträglich
No full textDie Emission von Treibhausgasen verursachen externe Kosten in signifikanter Höhe, die ein Marktversagen im Bereich der Energiewirtschaft darstellen. Zudem darf nur eine gewisse Menge an THG emittiert werden, um das 1,5° Ziel der Übereinkommens von Paris einzuhalten. Dieses Restbudget soll möglichst effizient auf die Marktteilnehmer verteilt werden. Das Europäische Emissionshandelsystem versucht durch feste jährliche Obergrenzen (CAP) sowie Auktionen und Handel von Berechtigungen (Trade) die Klimaziele zu gewährleisten. Zudem soll der EU-ETS sozialverträglich gestaltet werden. Der Vortrag erklärt die Grundlagen und geht auf Vor- und Nachteile und Schwierigkeiten bei der Umsetzung ein