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An Hochschulen ist eine zunehmende generationale Durchmischung der Beschäftigten zu beobachten (vgl. Gülker 2011). Erklärungsansätze, warum dies so ist, beziehen sich insbesondere auf zwei Entwicklungen: zum einen den demografischen Wandel, zum anderen einen sich verändernden Führungsstil in Organisationen.
The paper presents a bond graph model-based approach to active fault tolerant control (FTC) that makes use of residuals of analytical redundancy relations (ARRs). The latter ones are computed in order to decide whether a fault has occurred. Given a single fault hypothesis can be adopted, an advantage is that the time for isolating a fault among potential fault candidates that contribute to an ARR by means of parameter estimation may be saved and as long as ARR residuals are within their thresholds no input reconstruction at all is needed. It is shown that ARR residuals can be used for estimation of faults that can be isolated. ARR based input reconstruction is demonstrated by application to a buck-converter driven DC motor as a simple example of a switched power electronic system for which an averaged bond graph model is used. Scilab simulation runs confirm analytical results. If a required input cannot be determined analytically, it can be obtained by numerically solving a differential-algebraic equations (DAE) system.
Knowledge economics is the most important issue when designing an enterprise knowledge management system. This paper presents a 4-pillar-model which enables the design of an economically efficient knowledge management system and it documents how this model was applied to establish a knowledge management system in the internal consultancy unit of a large German enterprise in the information and communication technology sector. Eventually, the knowledge economics of the conceived system are assessed in order to improve the enterprise knowledge management system. The structure of the 4-pillar-model itself anticipates utility in all types of (re-) organisation projects.
We report on two experiments that deploy low-frequency audio and strong vibrations to induce haptic-like sensations throughout the human body. Vibration is quite frequently deployed in immersive systems, for example to provide collision feedback, but its actual effects are not well understood [Kruijff & Pander 2005; Kruijff et al. 2015]. The starting point of our experiments was a study by Rasmussen [Rasmussen 1982], which found that different vibration frequencies were experienced differently throughout the body. We will show how vibrations affect sensations throughout the body and may provide some directional cues to some parts of the body, yet also illustrate the difficulties.
Langfristige Finanzierungen tragen wesentlich zur Beruhigung der Märkte und damit zur Stabilität von Volkswirtschaften bei. Dies zeigt eindrucksvoll das Beispiel des deutschen Marktes für Wohnungsfinanzierungen. Bedingt durch die neuen Finanzmarktregulierungen wie Basel III und Solvency II wird sich der Markt für langfristige Finanzierungen jedoch verkleinern, da Banken Anreize erhalten, eher kurzfristige Darlehen zu vergeben. Andere Finanzintermediäre, etwa Versicherungen oder Fonds, werden diese Lücke kaum schließen können. Zwar werden alternative Finanzintermediäre aufgrund von Vorteilen in der Regulierung ihre Kreditvergabe erhöhen, aber wegen fehlender Erfahrungen und Anreize werden sie den Mangel an Langfristfinanzierungen nicht beheben können. Geboten ist daher eine Anpassung des Regelwerks, damit der Bankensektor robuster wird, gleichzeitig aber seine originären volkswirtschaftlichen Funktionen weiter erfüllen kann.
Die vorliegende Arbeit widmet sich dem Aufbau und Betrieb eines Teststandes zur kontinuierlichen solaren Methanreformierung. Für den Teststand, der in einem Hochleistungsstrahler aufgebaut wird, werden Verfahrenskomponenten sowie Mess- und Regelungstechniken ausgewählt, platziert und ein Regelungskonzept erstellt. Mit dem Programm LabVIEW werden die erfassten Mess- und Regelungsgrößen grafisch angezeigt, gespeichert und eine vor-läufige Bestimmung der Prozessgüte durchgeführt. Um die Qualität der Messergebnisse zu steigern, wird die Messunsicherheit der verwendeten Messtechnik berechnet. Für die solare Methanreformierung wird ein Absorber mit neuartiger Zweikanalstruktur in einen bereits bestehenden Receiver integriert. In der einen Hälfte der Kanalstruktur findet die Methanreformierungsreaktion statt. In den restlichen Kanälen kann ein Wärmeaustauch mit dem Medium Luft erfolgen, um einen Wärmespeicher zu beladen bzw. im Nachtbetrieb Wärme aus dem Speicher wieder in den Receiver einzukoppeln. Für die Inbetriebnahme werden Mess- und Regelungskomponenten kalibriert und ein Gaserhitzer für die Verwendung im Teststand entwickelt und optimiert. Weiterhin werden die Inbetriebnahme und Versuchspläne für die erste Testkampagne ausgearbeitet.
Lehren an Hochschulen
(2015)
Die Servicestelle Lehrbeauftragtenpool ist ein vom Bundesministerium für Bildung und Forschung (BMBF) gefördertes Verbundprojekt der Hochschulen Bonn-Rhein-Sieg, Düsseldorf, Niederrhein und Rhein-Waal. Unser Ziel ist es, die Qualität der Lehre zu verbessern, indem wir Menschen mit Berufserfahrung an die Hochschulen und in die Lehre bringen.
Extraction of text information from visual sources is an important component of many modern applications, for example, extracting the text from traffic signs on a road scene in an autonomous vehicle. For natural images or road scenes this is a unsolved problem. In this thesis the use of histogram of stroke widths (HSW) for character and noncharacter region classification is presented. Stroke widths are extracted using two methods. One is based on the Stroke Width Transform and another based on run lengths. The HSW is combined with two simple region features– aspect and occupancy ratios– and then a linear SVM is used as classifier. One advantage of our method over the state of the art is that it is script-independent and can also be used to verify detected text regions with the purpose of reducing false positives. Our experiments on generated datasets of Latin, CJK, Hiragana and Katakana characters show that the HSW is able to correctly classify at least 90% of the character regions, a similar figure is obtained for non-character regions. This performance is also obtained when training the HSW with one script and testing with a different one, and even when characters are rotated. On the English and Kannada portions of the Chars74K dataset we obtained over 95% correctly classified character regions. The use of raycasting for text line grouping is also proposed. By combining it with our HSW-based character classifier, a text detector based on Maximally Stable Extremal Regions (MSER) was implemented. The text detector was evaluated on our own dataset of road scenes from the German Autobahn, where 65% precision, 72% recall with a f-score of 69% was obtained. Using the HSW as a text verifier increases precision while slightly reducing recall. Our HSW feature allows the building of a script-independent and low parameter count classifier for character and non-character regions.
Advanced driver assistance systems (ADAS) are technology systems and devices designed as an aid to the driver of a vehicle. One of the critical components of any ADAS is the traffic sign recognition module. For this module to achieve real-time performance, some preprocessing of input images must be done, which consists of a traffic sign detection (TSD) algorithm to reduce the possible hypothesis space. Performance of TSD algorithm is critical.
One of the best algorithms used for TSD is the Radial Symmetry Detector (RSD), which can detect both Circular [7] and Polygonal traffic signs [5]. This algorithm runs in real-time on high end personal computers, but computational performance of must be improved in order to be able to run in real-time in embedded computer platforms.
To improve the computational performance of the RSD, we propose a multiscale approach and the removal of a gaussian smoothing filter used in this algorithm. We evaluate the performance on both computation times, detection and false positive rates on a synthetic image dataset and on the german traffic sign detection benchmark [29].
We observed significant speedups compared to the original algorithm. Our Improved Radial Symmetry Detector is up to 5.8 times faster than the original on detecting Circles, up to 3.8 times faster on Triangle detection, 2.9 times faster on Square detection and 2.4 times faster on Octagon detection. All of this measurements were observed with better detection and false positive rates than the original RSD.
When evaluated on the GTSDB, we observed smaller speedups, in the range of 1.6 to 2.3 times faster for Circle and Regular Polygon detection, but for Circle detection we observed a decreased detection rate than the original algorithm, while for Regular Polygon detection we always observed better detection rates. False positive rates were high, in the range of 80% to 90%.
We conclude that our Improved Radial Symmetry Detector is a significant improvement of the Radial Symmetry Detector, both for Circle and Regular polygon detection. We expect that our improved algorithm will lead the way to obtain real-time traffic sign detection and recognition in embedded computer platforms.
