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Innovation
Get PDFKolbeck, Felix: Innovations – who’s responsible?
Greischel, Peter: Innovating successfully in tourism
Chang, Celine & Werther, Simon: Innovations in HR management : Analysis of the winners of the Hospitality HR Award
Gruner, Axel: Camping – a sector seeing fundamental change
Humpe, Andreas & Kastner, Ralf & Mesch, Kerstin: Carbon-neutral air traffic by 2050? : New scenarios for aviatio
Structural analysis of a historical aircraft wing of Gustav Whiteheads No. 21
Get PDFZiel der vorliegenden Arbeit ist die strukturmechanische Analyse des historischen Flugzeugflügels der Nr. 21 von Gustav Weißkopf sowie des Nachbaus Nr. 21B, um strukturelle Eigenschaften der Flügelkonstruktion bewerten und damit ein Indiz bzw. Gegenindiz für die Flugfähigkeit der Nr. 21 liefern zu können, sowie einen Einstieg in die Themenstellung der simulatorischen Bewertung der Nr. 21 zu schaffen. Hierfür wird ein Modell erstellt, um die Machbarkeit der Simulationen mit numerischen Lösungsverfahren, sowie Fragen der Modellierung bewerten zu können. Auf der Basis einer Lastabschätzung für die verschiedenen Flugzustände, sowie einer berechneten Druckverteilung über den Flügel mit der allgemeinen Wirbelgittermethode werden die Spannungen und Verformungen in den Bambusholmen und in den Spannseilen des Flügels für die Belastungen im Flug ermittelt und bewertet. Einen wichtigen strukturellen Teil der Konstruktion stellt der Prozess der Vorspannung des Flügels über die Spannseile dar, welcher gesondert betrachtet und der Einfluss auf die Festigkeit im Flug beleuchtet wird. Des Weiteren werden verschiedene geometrische, formliche und lastverstärkende Variationen durchgeführt und bezüglich ihrer Flugtauglichkeit sowie der strukturellen Verbesserung diskutiert und dahingehend bewertet, dass ein Flug aus festigkeitstechnischen Gesichtspunkten möglich gewesen ist. Als Simulationsprogramm für die Validierung vorausgegangener strukturmechanischer Untersuchungen mit der Finiten-Elemente-Methode wurde ANSYS verwendet.The aim of the thesis is the structural-mechanical analysis of the historical aircraft wing of Gustave Whitehead’s No. 21 and of the replica No. 21B, in order to evaluate structural properties of the wing design and thus to be able to provide an indication or counter-indication for the flight capability of No. 21, as well as to present an introduction to the subject of the simulative evaluation of No. 21. For this purpose, a model is created in order to evaluate the feasibility of the simulations with numerical solution methods, as well as questions of modeling. Based on a load estimation for the different flight conditions, as well as a calculated pressure distribution over the wing area with the general vortex lattice method, the stresses and deformations in the bamboo spars and in the ropes of the wing are determined and evaluated for the loads during the flight. An important structural part of the design is the process of prestressing the wing via the ropes, which is considered separately and the influence on the strength of the structure during the flight is highlighted. Furthermore, different geometric, shape and load reinforcing variations are performed and discussed regarding their flightworthiness, as well as their structural improvement and evaluated in a way, that a flight has been possible in terms of structural-mechanical conditions. As a simulation program for the validation of the previous structural mechanical studies with the finite element method, ANSYS is used
Development of Air Quality Boxes Based on Low-Cost Sensor Technology for Ambient Air Quality Monitoring
Get PDFAnalyses of the relationships between climate, air substances and health usually concentrate on urban environments because of increased urban temperatures, high levels of air pollution and the exposure of a large number of people compared to rural environments. Ongoing urbanization, demographic ageing and climate change lead to an increased vulnerability with respect to climate-related extremes and air pollution. However, systematic analyses of the specific local-scale characteristics of health-relevant atmospheric conditions and compositions in urban environments are still scarce because of the lack of high-resolution monitoring networks. In recent years, low-cost sensors (LCS) became available, which potentially provide the opportunity to monitor atmospheric conditions with a high spatial resolution and which allow monitoring directly at vulnerable people. In this study, we present the atmospheric exposure low-cost monitoring (AELCM) system for several air substances like ozone, nitrogen dioxide, carbon monoxide and particulate matter, as well as meteorological variables developed by our research group. The measurement equipment is calibrated using multiple linear regression and extensively tested based on a field evaluation approach at an urban background site using the high-quality measurement unit, the atmospheric exposure monitoring station (AEMS) for meteorology and air substances, of our research group. The field evaluation took place over a time span of 4 to 8 months. The electrochemical ozone sensors (SPEC DGS-O3: R2: 0.71–0.95, RMSE: 3.31–7.79 ppb) and particulate matter sensors (SPS30 PM1/PM2.5: R2: 0.96–0.97/0.90–0.94, RMSE: 0.77–1.07 µg/m3/1.27–1.96 µg/m3) showed the best performances at the urban background site, while the other sensors underperformed tremendously (SPEC DGS-NO2, SPEC DGS-CO, MQ131, MiCS-2714 and MiCS-4514). The results of our study show that meaningful local-scale measurements are possible with the former sensors deployed in an AELCM unit
Selection of the most sensitive configuration of strip array detectors for x-ray beam monitoring in radiotherapy of cancer utilizing singular value decomposition
Get PDFWe propose a concise mathematical framework in order to compare detector configurations efficiently for x-ray beam monitoring in radiotherapy of cancer. This framework consists of the singular value decomposition (SVD) of the system matrix and the definition of an effective information threshold based on the relative error inequality utilizing the condition number of a matrix. The goal of this paper is to present the mathematical argument as well as to demonstrate its use for modeling the best detector configuration for monitoring x-ray beams in external beam therapy. This analysis depends neither on specific measurements of a given set of x-ray beams, nor does it depend in specific reconstruction algorithms of the beam shape, and therefore represents a configuration meta-analysis. In the results section, we compare three possible detector designs, each leading to a highly underdetermined system, and are able to determine their effective information content relative to each other. Furthermore, by changing design parameters, such as the geometric detector configuration, number of detectors, detector pixel size, and the x-ray beam blur, deeper insight in this challenging inverse problem is achieved and the most sensitive monitoring scheme is determined. Graphical Abstract Illustration of the general approach for performing configuration meta–analysis
Wintertourismus im Klimawandel : Auswirkungen und Anpassungsstrategien
No full textWintertourismus im Klimawandel : Auswirkungen und Anpassungsstrategie
HEP : Hochschulentwicklungsplan
Get PDFHochschulentwicklungsplan der Hochschule München aus dem Jahr 2018, englische Versio
Flip chip MEMS microphone package with large acoustic reference volume
Get PDFMEMS microphones must be further miniaturized for use in mobile devices. So we developed packaging technologies for MEMS microphones using flip chip technology instead of wire bonding. The first two generations have the sound hole in a ceramic interposer at the bottom side of the package. Now a new flip chip microphone package with the sound hole on the top side has been developed. The new package technology combines a large acoustic reference volume for good signal to noise ratio with small size. Compared to other microphone packages the sensitivity is improved by 3 dB. The front volume is small to avoid resonances in the acoustic frequency range