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As smart homes are being more and more popular, the needs of finding assisting systems which interface between users and home environments are growing. Furthermore, for people living in such homes, elderly and disabled people in particular and others in general, it is totally important to develop devices, which can support and aid them in their ordinary daily life. We focused in this work on sustaining privacy issues of the user during a real interaction with the surrounding home environment. A smart person-specific assistant system for services in home environment is proposed. The role of this system is the assisting of persons by controlling home activities and guiding the adaption of Smart-Home-Human interface towards the needs of the considered person. At the same time the system sustains privacy issues of it’s interaction partner. As a special case of medical assisting the system is so implemented, that it provides for elderly or disabled people person-specific medical assistance . The system has the ability of identifying its interaction partner using some biometric features. According to the recognized ID the system, first, adopts towards the needs of recognized person. Second the system represents person-specific list of medicines either visually or auditive. And third the system gives an alarm in the case of taking medicament either later or earlier as normal taking time.
Proceedings of DELFI Workshops 2021
13.09.2021
Dortmund (Online), Deutschland
Process Monitoring in Steel-Mills using Impedance Analysis: VNA Improvement for Data Acquisition
(2017)
The process automation extends over every manufacturing step of a product in the steel-mill to increase the quality, quantity and energy efficiency. The product dimensions are an important part of the quality control; these must maintain the specified tolerances. Additional to the cross-sectional-area, the measured data contains much more information about the manufacturing process, e.g. eccentricity, condition of the rolls and defects of the rod. For analyzing the measured data and to gather more information about the manufacturing process it is necessary to increase the speed of the data acquisition by performing some modifications of the VNA, e.g. faster analog to digital converter and microcontroller, improved firmware and optimized values of the passive electrical components for faster time constants and transient responses.
Es ist eine alltägliche Erfahrung, daß wir Urteile über gut oder schlecht, bzw. qualitativ hochwertig oder minderwertig eines Gegenstandes mit der Wahrnehmung des emittierten Geräuschschalls in Verbindung bringen. Der Geräuschlaut ist deshalb ein wichtiges Entscheidungskriterium bei der Auswahl eines Produktes, welches wahrnehmbaren Schall erzeugt. Die Fragestellung hinsichtlich der Geräuschqualität und des Geräuschdesigns stellt daher hohe Anforderungen an den Akustik-Ingenieur. Zum heutigen Zeitpunkt ist es jedoch nicht möglich, mit einer instrumentellen Meßtechnik Aussagen über die Eignung eines Geräuschschalls für ein Produkt zu machen. Es ist nicht möglich, kognitive Faktoren über eine instrumentelle Meßtechnik zu messen. Es reicht nicht aus, eine Geräuschgüte mit Bewertungsschemata wie dem A-bewerteten Schalldruckpegel
oder Lautheitsmodellen zu definieren. Diese lassen allein keine eindeutigen Aussagen über die Wahrnehmung von Geräuschen zu. Der vorliegende Beitrag ist als Ansatz für das Soundengineering von Fahrzeuginnengeräuschen zu sehen. Es wird anhand von Hörversuchen mit Fahrzeuginnengeräuschen ein objektiver Beschreibungskatalog ermittelt, der eine Aussage über die jeweilige Hörempfindung zuläßt.
Es konnte in dieser Arbeit festgestellt werden, das Relationship Marketing eher eine Akzentuierung
des traditionellen Marketing darstellt und aufgrund der Inkonsistenzen in den einzelnen Ansätzen
kein neues Marketing Paradigma darstellt. Wenn Relationship Marketing sich zu einem neuem
Marketing Paradigma entwickeln soll, dann muss vor allen Dingen die Erschaffung von Werten, der
Verlauf von Beziehungen und deren Entstehung im Vordergrund stehen. Um den evolutorischen
Weg des Relationship Marketing voranzutreiben und im Vertrauensmanagement Kundenbindungen
zu beschreiben, wurde eine im E-Commerce gültige Typologie erstellt, welche qualitative
Ausprägung der Kundenbindung durch die Antezedenz Variable Vertrauen beschreibt. Den Beleg
der Existenz einer solchen Typologie brachte das im Verlauf dieser Abschlussarbeit entwickelte
Messinstrumentes einer qualitativen Ausprägung mittels Vertrauen. In der folgenden Diskussion
konnte zudem gezeigt werden, dass die Typologie in die drei wichtigsten Denkrichtungen des
Relationship Marketing integriert werden kann und somit eine Methode zur Ermittlung qualitativer
Ausprägungen der Kundenbindung im jetzigen Verständnis von Relationship Marketing darstellt.
Relax yourself - Using Virtual Reality to enhance employees mental health and work performance
(2019)
This paper presents work-in-progress aiming to develop an actively adapting virtual reality (VR) relaxation application. Due to the immersive nature of VR technologies, people can escape from their real environment and get into a relaxing state. Goal of the application is to adapt to the users' physiological signals to foster the positive effect. Until now, a first version of the VR application was constructed and is currently evaluated in an experiment. Preliminary results of this study demonstrate that people appreciate the immersion into the virtual environment and escape from reality. Moreover, participants highlighted the option to adapt users' needs and preferences. Based on the final study data, the constructed application will be enhanced with regard to adoption and surrounding factors.
Resource Usage in Online Courses: Analyzing Learner’s Active and Passive Participation Patterns
(2015)
The paper analyzes the experience with an open university course for a very heterogeneous target group in which MOOC-like materials and activities were used. The course was conducted in a specifically prepared and extended Moodle environment. The analysis involves questionnaires as well as performance data that reflect the resource access on the learning platform. A special focus is put on the participants’ acceptance and usage of student-generated versus teacher-provided learning content. Network analysis techniques have been used to identify "interest clusters" of students around certain resources.
The Bitcoin whitepaper states that security of the system is guaranteed as long as honest miners control more than half of the current total computational power. The whitepaper assumes a static difficulty, thus it is equally hard to solve a cryptographic proof-of-work puzzle for any given moment of the system history. However, the real Bitcoin network is using an adaptive difficulty adjustment mechanism. In this paper we introduce and analyze a new kind of attack on a mining difficulty retargeting function used in Bitcoin. A malicious miner is increasing his mining profits from the attack, named coin-hopping attack, and, as a side effect, an average delay between blocks is increasing. We propose an alternative difficulty adjustment algorithm in order to reduce an incentive to perform coin-hopping, and also to improve stability of inter-block delays. Finally, we evaluate the presented approach and show that the novel algorithm performs better than the original algorithm of Bitcoin.
Roboter und Arbeitsplätze
(2022)
Das Ziel dieser Bachelorarbeit ist es, einen Zusammenhang zwischen den Roboterzahlen und der Arbeitslosigkeit herauszuarbeiten. Zunächst werden die Beschäftigungseffekte durch den Einsatz von Robotern beschrieben. Anschließend werden unterschiedliche Daten von mehreren
Ländern aus dem Jahr 2020 anhand einer empirischen Regression analysiert, sodass schlussfolgernd interpretiert werden kann, ob Beziehungen zwischen der Anzahl an Robotern und der Arbeitslosenquote bestehen.
In den letzten Jahren sind unzweifelhaft technologische Durchbrüche gelungen, es entstanden Innovationen von selbstfahrenden Autos bis hin zu Künstlichen Intelligenzen. Die Auswirkungen der technischen Neuerungen lassen auf der einen Seite Hoffnungen und auf der
anderen Seite Ängste und Befürchtungen entstehen. Während die Hoffnungen darauf beruhen, dass das menschliche Leben durch die Hilfe von Robotern erleichtert wird, richtet sich der Kern
der Befürchtungen auf die Ambivalenz des technischen Fortschritts bei seinen Auswirkungen auf Produktion und Beschäftigung.
In dieser Arbeit stehen die Roboter im Mittelpunkt. Aufgrund der vielseitigen Einsatzmöglichkeiten, die diese Roboter vorweisen, entsteht die Besorgnis, dass dies bald zu einem „Ende der Arbeit“ führen könnte.
Vor dem Hintergrund globaler Vernetzung, Digitalisierung und Big Data geht das Excel-Zeitalter seinem Ende entgegen. Neue Technologien versprechen eine höhere Effizienz und Effektivität des Controllings. Die Veränderungen umfassen dabei alle Aufgabenbereiche des Controllings – allerdings mit unterschiedlicher Geschwindigkeit und differenzierten Lösungsansätzen. Der vorliegende Beitrag untersucht drei Technologien, die im Controlling derzeit besonders stark diskutiert werden: Robotic Process Automation, Predictive Analytics und Künstliche Intelligenz. Im Rahmen eines Forschungsseminars an der Hochschule Ruhr West in Mülheim a.d.R. wurden dazu 57 Führungskräfte aus Controlling und Rechnungswesen befragt. Über 75% der befragten Unternehmen halten die Digitalisierung für wichtig, mehr als die Hälfte (52%) beabsichtigen, eine oder mehrere der drei untersuchten Technologien in den nächsten drei Jahren neu einzusetzen. In den Aufgabenbereichen ist bislang vor allem das Reporting digital unterstützt, in der Strategischen Planung und im Risikomanagement ist dagegen die Digitalisierung gering. Wesentliche Hindernisse sehen die Befragten im fehlenden Know-How und mangelnder Veränderungsbereitschaft.
For the rod shape measurement of hot rolled round steel bars (rods) the high frequency eddy current method is especially well suited as it requires no contact point and is not limited to below the Curie temperature. Defects of the rod's shape can be detected by measuring the impedance spectrum of the RLC-oscillator. In the first laboratory setup an Agilent impedance analyser was used for initial tests. Nevertheless, this setup cannot be applied in a steel plant due to the difficult environmental conditions. Hence, a vector network analyser for passive impedance measurement that is applicable in these surroundings was developed.
Methods of red-hot rod shape testing require a robust non-contact measurement principle as a touch point could lead to damages to the rod and the detection unit. Therefore a new basic approach based on high frequency eddy current (HFEC) has been investigated. Due to the robustness and the ability to determine the rod shape even above the Curie temperature this principle is especially well suited and can be implemented in the production process directly. The first automatic measurement setup was successfully developed with promising results. Hereby a defect of ovality was detected with a parallel RLC-oscillator. The capacity of this RLC-oscillator is constant whereas the inductance is the measurement part that varies due to eddy current interactions with the rod.
Quality and dimensional accuracy of hot rolled steel rods depend on several process parameters. In fact many of these crucial parameters are not be sufficiently determined yet. By improving automation and process control costs and scrap of production can be decreased. As part of the research project PIREF, one of these parameters – the roll gap – is under investigation beside other topics. Before starting rolling, the roll gap is typically set to a fixed value according to the planed dimensions of the product, but the forces during the rolling of the rod cause an enlargement of the roll gap. In which way the rolls change their position and form shall be examined in our research project. Therefore a first experimental setup has been built up to determine the change in position of the rolls under applied force. This is realized by a pot core coil as sensor using impedance analysis. The first results are presented in this work as a proof-of-principle.
To reduce the number of traffic accidents and to increase the drivers comfort, the thought of designing driver assistance systems arose in the past years. Fully or partly autonomously guided vehicles, particularly for road traffic, pose high demands on the development of reliable algorithms. Principal problems are caused by having a moving observer in predominantly natural environments. At the Institut fur Neuroinformatik methods for analyzing driving relevant scenes by computer vision are developed in cooperation with several partners from the automobile industry. We present a solution for a driver assistance system. We concentrate on the aspects of video-based scene analysis and organization of behavior.
The scene interpretation and the behavior planning of a vehicle in real world traffic is a difficult problem to be solved. If different hierarchies of tasks and purposes are built to structure the behavior of a driver, complex systems can be designed. But finally behavior planning in vehicles can only influence the controlled variables: steering, angle and velocity. In this paper a scene interpretation and a behavior planning for a driver assistance system aiming on cruise control is proposed. In this system the controlled variables are determined by an evaluation of the dynamics of a two-dimensional neural field for scene interpretation and two one-dimensional neural fields controlling steering angle and velocity. The stimuli of the fields are determined according to the sensor information.
We present an architecture based on the Dynamic Field Theory for the problem of scene representation. At the core of this architecture are three-dimensional neural fields linking feature to spatial information. These three-dimensional fields are coupled to lower-dimensional fields that provide both a close link to the sensory surface and a close link to motor behavior. We highlight the updating mechanism of this architecture, both when a single object is selected and followed by the robot's head in smooth pursuit and in multi-item tracking when several items move simultaneously
Die Hochschule Ruhr West hat erstmals zum Wintersemester 2011/12 ein Schülerstudium im Studiengang Angewandte Informatik angeboten. Dieses ist aus verschiedenen Aktivitäten zum Übergang Schule - Hochschule hervorgegangen. Der Artikel beschreibt die Erfahrungen bei der Einführung eines solchen Programms an einer sich im Aufbau befindlichen Fachhochschule sowohl aus Sicht der Hochschulangehörigen als auch der teilnehmenden Schülerinnen und Schüler.
Sensor-/Aktorsystem zur Überwachung und Unterstützung der Thermoregulation von Intensivpatienten
(2023)
Diese Bachelorarbeit ist dem Thema Sensor-/Aktorsystem zur Überwachung und Unterstützung von Intensivpatienten gewidmet, einem Bereich, der durch schnelle Fortschritte in der Technologie und der Biomedizin beeinflusst wird. Hier bildet die Körperkerntemperatur einen entscheidenden Bestandteil und einen bedeutenden physiologischen Parameter, der nicht nur für die Funktion des menschlichen Körpers wesentlich ist, sondern auch wertvolle Informationen über den Gesundheitszustand eines Patienten liefert. Im Rahmen dieser Arbeit werden sowohl die physiologische Bedeutung als auch die technologischen Methoden zur Messung der Körperkerntemperatur behandelt. Das Ziel ist, ein Verständnis für die Notwendigkeit einer präzisen Überwachung dieser Parameter bei Intensivpatienten zu entwickeln, indem die Grundlagen der Körperkerntemperatur und ihre Bedeutung für den Organismus im Fokus stehen. Die Einbeziehung von Sensor- und Aktorsystemen in die Intensivmedizin verspricht eine bessere Pflege und klinische Entscheidungsfindung, was zu optimierten Behandlungsergebnissen führen kann. Das Thema der vorliegenden Arbeit hat eine Relevanz für die moderne Gesundheitsversorgung und intendiert wird, Einblicke in innovative Ansätze zur Verbesserung der Pflege von Intensivpatienten zu bieten. Zudem soll die Gesundheitsversorgung der allgemeinen Gesellschaft weiter vorangebracht werden.
This Paper presents a new service-learning setting based on the collaboration of engineering students and people with disabilities. The implementation at a German university is described and first results from two years of experience are shown. The objective of this case study is to show a transferable best practice concept with impact.
Die folgende Bachelorarbeit analysiert und wertet die Messdaten eines Niederschlagsensors aus, der auf dem induktiven Wirbelstromprinzip aufbaut. Der Sensor wird an der Hochschule Ruhr West im Institut für Mess- und Sensortechnik entwickelt. Er soll nach erfolgreicher Konfiguration die Niederschlagsintensität und die Tropfengröße über die Resonanzfrequenz der Spule ausgeben können. Um dieses Ziel zu erreichen, gibt die Bachelorarbeit eine Einschätzung, inwieweit das System für eine Niederschlagserfassung geeignet ist und welche Verbesserungen vorgenommen werden können. Dazu wurden die Messdaten in einer Regenkammer der Firma Lambrecht meteo GmbH erfasst. Für die Versuche wurden zwei Flachspulen mit Resonanzfrequenzen von 1,7 MHz und 8 MHz nacheinander ausgewertet. Die resultierenden Messdaten werden sowohl im Zeit- als auch im Frequenzbereich auf Verhaltensmuster und Kennwerte untersucht. Aus den Ergebnissen geht hervor, dass der Sensor aufgrund von äußeren Einflüssen und inneren Verhaltensweisen keine signifikante Antwort auf den Niederschlag ausgibt, um die Niederschlagsintensität und die Tropfengröße zu ermitteln. Dennoch zeigt sich, dass die Resonanzfrequenz der Spulen gegensätzliche Reaktionen hervorruft. Die Spule mit der Resonanzfrequenz von 1,7 MHz reagiert deutlich unempfindlicher auf äußere Einflüsse wie parasitäre Kapazitäten. Allerdings werden nur Regentropfeneinschläge bei hohen Niederschlagsmengen deutlich erkannt. Die Spule mit der Resonanzfrequenz von 8 MHz hingegen zeigt ein empfindlicheres Verhalten auf äußere Einflüsse. Zur Optimierung des Niederschlagssensors, muss dieser konfiguriert werden, damit er äußeren Einflüssen robust entgegenwirkt und den Niederschlag sensibel genug detektiert. Zudem müssen Ausreißer, die in der Frequenzanalyse entdeckt wurden und von den inneren Verhaltensweisen stammen, entfernt werden.
Simulated reality environment incorporating humans and physically plausible behaving robots, providing natural interaction channels, with the option to link simulator to real perception and motion, is gaining importance for the development of cognitive, intuitive interacting and collaborating robotic systems. In the present work we introduce a head tracking system which is utilized to incorporate human ego motion in simulated environment improving immersion in the context of human-robot collaborative tasks.
Durch die immer weiter voranschreitende Digitalisierung sind, nicht nur Nutzer:innen
sozialer Medien, kaum noch Grenzen gesetzt. Hier stehen erhebliche Nutzungspotenziale
digitaler Technologien, nahezu unerforschten Auswirkungen, auf die Anwender:innen,
gegenüber (Netzwerk Stiftungen und Bildung, 2021).
Die Zahlen der Social Media Nutzer:innen steigen. Derweil verzeichnet sich, unter den
beliebtesten Social Media Plattformen, zu meist in der jüngeren Altersgruppe, der Großteil
der Anwender:innen (ARD & ZDF, zitiert nach de.statista.com, 2021). Während die
Methoden der Designer:innen immer weiter ausgereift werden und sich dabei neuester
Erkenntnisse der Psychologie und Verhaltensforschung bedienen. So wird unter dem
Begriff Dark Patterns beschrieben, dass sich Designer:innen Wissen über menschliches
Verhalten und die Wünsche der Anwender:innen zu Nutze machen, um dezeptive Funktionalitäten
zu implementieren, die nicht im Interesse der Anwender:innen liegen (Gray,
Kou, Battles, Hoggatt & Toombs, 2018).
In den Bildungsbereichen fehlt es jedoch bisher, vor Allem in Bezug auf Selbstbestimmung
im digitalen Anwendungskontext, an Konzepten zur Auseinandersetzung mit den
Auswirkungen von Dark Patterns auf die persönliche bzw. selbstbestimmte Nutzung.
In diesem Zusammenhang ist das Ziel der vorliegenden Arbeit die Erarbeitung eines
Workshop Konzepts, zur problemorientierten Diskussion von Dark Patterns, unter adoleszenten
Anwender:innen und deren Förderung im selbstbestimmten Umgang mit Social
Media.
Zudem folgt in diesem Rahmen eine qualitative Erhebung, um zu erfassen, ob die Teilnehmer:
innen fähig sind sich mit der Thematik Dark Patterns auseinanderzusetzen und
in der Lage sind Lösungsansätze zu entwickeln, um den Auswirkungen von Dark Patterns
entgegenzuwirken und die eigene selbstbestimmte Social Media Nutzung zu fördern.
Stichworte des Autors:
Dark Patterns, Social Media, digitale Selbsbestimmung, Workshop Konzept, Qualitative
Erhebung
Global software development changes the requirements in terms of soft competency and increases the complexity of social interaction by including intercultural aspects. While soft competency is often seen as crucial for the success of global software development projects, the concrete competence requirements remain unknown. Internationalization competency represents one of the first attempts to structure and describe the soft competence requirements for global software developers. Based on the diversity of tasks, competence requirements will differ among the various phases of software development. By conducting a survey on the importance of internationalization competences for the different phases of global software development, we identified differences in terms of competence importance and requirements in the phases. “Adaptability” (of one's working style) and “Cultural Awareness” were the main differences. “Cultural Awareness” distinguishes requirements engineering and software design from testing and implementation while “Adaptability” distinguishes implementation and software design from requirements engineering and testing.
Im Rahmen dieser Bachelorarbeit werden Dehnungsmessstreifen (DMS)
mittels Faktor kalibriert, da die DMS unterschiedlich positioniert sind. Auf
Grund der manuellen Applikation stellen die DMS unterschiedliche Dehnungen
dar, dies soll mit Hilfe einer Kalibrierung der DMS verhindert werden. Damit
die DMS kalibriert werden können, werden die DMS in einer Viertelbrücke
gemessen und anschließend mit Hilfe einer Messkarte in Matlab eingelesen.
Im Matlab werden die Daten anschließend weiterverarbeitet, so dass jeder
DMS seinen eigenen Faktor bekommt. Anschließend werden die DMS in eine
Vollbrücke und Zweiviertelbrücke verrechnet, damit die reine Biegedehnung
sowie reine Zugdehnung berechnet werden kann.
Human computer interaction in security and time-critical systems is an interdisciplinary challenge at the seams of human factors, engineering, information systems and computer science. Application fields include control systems, critical infrastructures, vehicle and traffic management, production technology, business continuity management, medical technology, crisis management and civil protection. Nowadays in many areas mobile and ubiquitous computing as well as social media and collaborative technologies also plays an important role. The specific challenges require the discussion and development of new methods and approaches in order to design information systems. These are going to be addressed in this special issue with a particular focus on technologies for citizen and volunteers in emergencies.
Stationäre Rohrströmungen
(2024)
Stress im Informatikstudium
(2020)
Einführung
Ziel der vorliegenden Thesis ist es, die Eu- und Disstressoren der Infomatikstudierenden an der Hochschule Ruhr West zu untersuchen. Hierzu sollen nach den Wünschen der neuen Beratungsstelle für den Studienstress die Studierenden befragt werden. Nachfolgend werden in der Thesis die bekannten Problematiken im Informatikstudium eingebunden. Zusätzlich sollen die Informatikstudierenden auf den Stress mit einem Cartoon-Video aufmerksam gemacht werden. Mithilfe des Videos sollen die zukünftigen Eu- und Disstressoren rechtzeitig erkannt und Hilfe an der Hochschule Ruhr West abgeholt werden.
Methode
Die Untersuchung der Stressoren wird mit einem Fokusgruppeninterview (N = 4) und mit einer Online-Fragebogenerhebung (N = 120) durchgeführt. Die Signifikanzprüfungen sind varianzanalytisch und die Abweichungen der Gruppen werden mit t-Tests und einfaktorieller ANOVA berechnet.
Ergebnisse
Die Ergebnisse zeigen Unterschiede zwischen den Stressoren in unterschiedlichen Gruppen. Vor allem in den Gruppen mit davor erworbenen Vorkenntnissen und mit verschieden bewerteten Fachkompetenzen. Insbesondere ist der Stresslevel zwischen den Geschlechtern und bei den Informatikstudierenden, die mehrmals im Studium erkrankt waren, unterschiedlich.
Schlussfolgerung
Die Ergebnisse sind für die aktuellen Stresssituationen im Informatikstudium und für die nächsten Studien relevant. Außerdem wird mit dieser Studie auch auf die Problematiken in der Informatik, wie z. B. dem Frauenmangel in der Informatik, die den Informatikstudierenden den Stress verursachen könnten, aufmerksam
gemacht.
Das Studienbuch gibt einen praxisorientierten Einstieg in die Thematik des E-Learnings. Neben Grundlagenkenntnissen werden die Funktionen von Learning-Management.Systemen diskutiert und praxisnah am Beispiel Moodle vertieft. In weiteren Kapiteln wird auf die Administration und den Aufbau von E-Learning-Kursen eingegangen. Neben der Vorstellung unterschiedlicher Contentformen liegt der Schwerpunkt hierbei auf der systematischen Vorgehensweise zur Erstellung. Abschließend werden Möglichkeiten behandelt, die mobile Endgeräte heute zum Lernen bieten.
Zahlreiche praktische Übungen mit Musterlösungen begleiten den Text und erleichtern das Selbststudium. Wiederholungsfragen am Ende jedes Kapitels dienen der Vertiefung des Erlernten.
The development of innovative measuring technology for process optimization in hot rolling mills becomes more and more relevant because of increasing demands on product quality. Measurement technology for high-resolution non-contact cross-sectional area measurement has shown that the variation in cross-sectional area contains information about the rolling process. This information can be used for the development of new measurement devices and analytical methods for process optimization. The harsh environmental conditions and strict safety regulations result in great effort when implementing a new sensor prototype in hot rolling mills. For this reason, this work presents a mechatronic test stand that can simulate the cross-sectional area variation under laboratory conditions realistically.
LEDs gelten als umweltfreundliche Beleuchtungstechnik. Für die Massenanwendung arbeiten die LED-Hersteller an einer Senkung der Kosten bzw. einer Erhöhung der Ausbeute, insbesondere bei der aufwendigen LED-Kristallbeschichtung auf den Wafern. Während der Beschichtung (MOCVD) werden optische In-situ-Messgeräte zur Überwachung des Prozesses genutzt. Die hier vorgestellte Untersuchung beschäftigt sich mit dem Einfluss von Super-Photolumineszenz-Effekten bei einer möglichen In-situ-Prozesskontrolle in der MOCVD.
Developing an intelligent chatbot that can imitate human-to-human interaction has become important in recent years. For this reason, many studies have been conducted to evaluate the quality of chatbots. Furthermore, various approaches and tools, such as sentiment analysis, have been created to improve the performance of chatbots.
This study examines previous research to identify the quality dimensions used to measure chatbots performance in order to develop a general chatbot assessment model that evaluates and compares chatbots quality. The developed evaluation model measures ten chatbot quality dimensions. This model is based on user experience. It requires human testers to interact with the chatbot to test its functioning and then a quantitative approach is used to collect data from user testing by conducting a survey with these testers. In this survey, they are instructed to evaluate the quality of the chatbot using a questionnaire that contains the items needed to evaluate each dimension.
This study also investigates whether sentiment analysis can improve the quality of chatbots and, if so, to identify the dimensions improved with sentiment analysis. For this reason, two chatbot versions are implemented using the Rasa framework (one that cannot detect sentiment and the other that analyzes sentiment and responds accordingly).
Following that, we used our evaluation model to evaluate and compare the two chatbot versions with two groups of participants by conducting a survey. In this survey, each group tested the functioning of one version. Then, both groups were instructed to use the items of the evaluation model to evaluate the version they tested. The goal of this survey was to evaluate the validity and reliability of the items used in the evaluation model to evaluate chatbots, and also to determine if sentiment analysis improved the chatbot quality by comparing survey results between the two groups. The results show that items used in the assessment model to evaluate chatbots are valid and reliable. The findings also indicate that sentiment analysis improves the chatbot’s quality. However, it improves the quality of some dimensions but not the majority of them.
Mobile devices, in the form of smartphones, are endowed with rich capabilities in terms of multimedia, sensors and connectivity. The wide adoption of these devices allows using them across different settings and situations. One area in which mobile devices become more and more prominent is within the field of mobile learning. Here, mobile devices provide rich possibilities for the contextualization of the learner, by using the set of sensors available in the device. On the one hand, the usage of mobile devices enables participation in learning activities independent of time and space. Nevertheless, developing mobile learning applications for the heterogeneity of mobile devices available in the market becomes a challenge. Not only this is a problem related to form factor aspects, but also the large number of different operating systems, platforms and app infrastructures (app stores) are aspects to be considered. In this paper we present our initial efforts with regard to the development of cross-platform mobile applications to support the contextualization of learning content.
RELEVANCE & RESEARCH QUESTION: Currently the effectiveness of Virtual Reality (VR) and Augmented Reality (AR) systems as practice teaching methods are virtually uncharted. The proof that these systems can provide the same or better learning outcomes than a text instructed practical task could represent a significant benefit for educational activities. METHODS & DATA: To fathom the effectiveness, an experimental study with the three conditions (VR, AR and a real setup) were used to teach participant how to assemble a standard computer. Each condition was divided into two parts: part one in which participants were confronted with their specific scenario, part two in which participants had to go through a real practice after one week. The learning outcome was determined by the designation of hardware parts, a quiz that queried their function and the correct assembling of the components in addition to needed time. Apart from the mere performance, the acceptance of such application in academic context and difference in evaluation by men and women were of interest. RESULTS: Results concerning the Learning Outcome showed that participants from the VR condition outperformed those learned from the real setup ((M=10.0, SD=0.0) [virtual reality] vs. (M=8.95, SD=1.27) [control]). Furthermore, results from the assembling duration assessment demonstrated that VR Group Participants completed their tasks 6.62% faster than the control group. Regarding the identification of Hardware Parts, both groups scored a significant improvement during the post condition compared to the first test run, indicating a learning progress. However, due to the VR group achieving a better outcome in average answers and a more significant difference between the trials, the results indicate a better performance by participants assigned to the VR condition. ADDED VALUE: The results revealed that VR and AR systems could exceed text-based approach in terms of learning outcome performance. The effectiveness of the systems implicates a major benefit for the educational landscape, as learning content that is not realizable in terms of cost, distance or logistics could be designed as an immersive and engaging experience.
Technical Report
(2016)
This internal report discusses the theoretical and practical aspects of the cluster management framework SimpleHydra, which was developed in order to allow researchers the quick setup of classical small to mid-scale computation clusters while being as lightweight and platform independent as possible. We motivate crucial design choices with a theoretical analysis in the aspect of time and space complexity, furthermore we give a comprehensive introduction regarding the frameworks usage (which includes examples and detailed description of fundamental concepts as well as data structures). In addition to that we illustrate application scenarios with complete source code examples. Furthermore we hope that this document proves valuable not only as a development report but also as a practical manual for SimpleHydra.
Systeme zur automatisierten Bildanalyse sind vielfältig einsetzbar und gewinnen aufgrund technologischer Weiterentwicklungen und gesellschaftlicher Akzeptanz zunehmend an Bedeutung. Schwerpunkt im Bereich der "Technischen Bildverarbeitung dynamischer Szenen" ist die Entwicklung von Methoden, die bei der Interpretation von Bildern aus verschiedenen Sensordaten Verwendung finden. Dies sind neben den herkömmlichen Kamerabildern im wesentlichen Röntgen- und Radarbilder. Unter geeigneter Berücksichtigung der durch die jeweiligen Anwendungen vorgegebenen Randbedingungen werden daraus entsprechende Verfahren abgeleitet. Derzeitige Projekte beschäftigen sich mit der Analyse von Straßenverkehrsszenen, der Detektion von Sprengstoffzündern bei der Durchleuchtung von Fluggepäck, sowie mit der Bestimmung von Art und Ausdehnung von Ölverschmutzungen bei der Meeresüberwachung.
Technologie die beflügelt
(2016)
Durch den technischen Fortschritt in der Spracherkennung und -verarbeitung wird Sprache als Interaktionsform auch in Fahrzeugen, z.B. zur Bedienung von Infotainmentsystem, immer populärer. Die Steuerung von teilautomatisierten Fahrzeugen über Sprache ist bisher wenig erforscht. Ziel dieser Arbeit ist es unter der grundsätzlichen Annahme der Eignung von Sprachsteuerung für teilautonome Fahrzeuge, Nutzererwartungen und spezielle Anforderungen an eine Sprachsteuerung für die grundlegenden Fahrmanöver zu identifizieren. Aus den Ergebnissen eines Expertenworkshops und einer explorativen Videostudie werden Anforderungen und Sprachkommandos abgeleitet.
Temporal stabilization of discrete movement in variable environments: An attractor dynamics approach
(2009)
The ability to generate discrete movement with distinct and stable time courses is important for interaction scenarios both between different robots and with human partners, for catching and interception tasks, and for timed action sequences. In dynamic environments, where trajectories are evolving online, this is not a trivial task. The dynamical systems approach to robotics provides a framework for robust incorporation of fluctuating sensor information, but control of movement time is usually restricted to rhythmic motion and realized through stable limit cycles. The present work uses a Hopf oscillator to produce discrete motion and formulates an online adaptation rule to stabilize total movement time against a wide range of disturbances. This is integrated into a dynamical systems framework for the sequencing of movement phases and for directional navigation, using 2D-planar motion as an example. The approach is demonstrated on a Khepera mobile unit in order to show its reliability even when depending on low-level sensor information.
Artificial intelligence (AI) is one of the most auspicious yet controversial technologies with virtually unlimited potential to solve almost all of the existential problems humanity is facing today.1 Huge resources are poured into the development, testing and application of AI that is supposed to be utilized in almost all areas of everyday life.2 It may be used to combat genetically inherited diseases, to revolutionize the economy, to bring prosperity and equality to everyone and to counter the effects of climate change.3 With AI as the enabling technology humanity may experience a better future. Today, AI capabilities can already drastically improve analytic processing tasks and algorithmic systems and have beaten humans in games such as chess.4 Yet, AI and all of its applications bring about a myriad of ethical challenges. Revolutionary weapon systems that achieve autonomy via AI and genome-editing powered by AI are just some specific examples.5 An omnipotent AI will be either the greatest or the vilest thing that has happened to humanity in its brief existence.6 However, even today more and more computational devices are connected to each other, spurring a huge increase in global data streams that can be used to further train and enhance AI systems.
The prowess of AI for executing analytic tasks paves the way for the use of AI in more and more applications. One of these applications, that shows great promise, is the use of AI in surveillance applications.7 AI surveillance applications are proliferating at a fast rate, with a number of appli-cations already being in use today.8 These applications are aimed at accomplishing a number of policy objectives, some are in accordance with basic human laws, some are definitely not and some
1 Cf. Hawking (2018). P. 183ff
2 Cf. Hawking (2018). P. 183ff.
3 Cf. Hawking (2018). P. 183ff.
4 Cf. Burton (2015). P. 1ff.
5 Cf. Hawking (2018). P. 183ff.
6 Cf. Hawking (2018). P. 183ff.
7 Cf. Feldstein (2019). P. 1.
8 Cf. Feldstein (2019). P. 1.
2
belong in the nebulous area in between lawful and unlawful.9 But what are lawful and unlawful uses of AI surveillance systems and what are their ethical implications?
This thesis will examine the ethical implications of AI based mass surveillance systems and try to answer the first central question, if it is possible to use AI based mass surveillance applica-tions in an ethical way. Furthermore, the thesis will attempt to answer the second central ques-tion and find out how the ethical use of AI based mass surveillance systems, if this ethical use is possible, materialize. Governmental agencies will be in the focus of this discussion, as their use of the technology may have bigger ethical challenges. Yet private companies will play a part as well. In an attempt to accomplish these two aims, the thesis will inspect the basics of ethics and possible ethical theories that can be utilized to answer the questions. Normative ethics will be stud-ied first with a focus on consequentialism and utilitarianism. To gain a deeper understanding of utilitarianism, act and rule utilitarianism will be compared. Afterwards, deontological theories will be the focus of the discussion with a concentration on deontological pluralism. Next, the mentioned theories will be evaluated, discussing advantages and weak spots of the theories, to assess which theory may serve as the ethical framework of this thesis and the subsequent answer to the two main questions.
The next step will be the establishment of the AI framework. This contains the definition of AI and a distinction of terms that are commonly used in the its environment such as automation and au-tonomy. The importance of data for AI will be discussed. Afterwards, the technological basis of AI will be outlined, discussing key concepts such as machine learning and deep learning. Addi-tionally, it will be examined how an AI learns. The possible uses of AI in general will be outlined in a brief fashion, blazing the trail to discussing the moral challenges of AI. Afterwards, the current pace of AI development will be studied.
In the chapter that follows, the use of AI in surveillance technology is going to be highlighted. The possible ways of how AI can be used for surveillance purposes are reviewed here, discussing facial
9 Cf. Feldstein (2019). P. 1.
3
and behavioral recognition systems, smart cities, smart policing, communications/data driven sur-veillance and their enabling technologies. Then, the global proliferation of AI surveillance systems is going to be outlined.
Subsequently, the accordance of AI surveillance with basic human laws and rights, such as the right to privacy, will be checked to find out if the law and the international framework of human rights allow for AI surveillance or at least have restrictions that would greenlight the use of AI surveillance technology. All the aspects of the thesis, especially including the selected ethical framework, will be combined in this last section in order to enable the adaptation of a framework that allows to find out, if AI surveillance systems can be ethically permissible while also creating insights how this ethical AI surveillance system must be engineered. To finish, the thesis will end with a conclusion.
Today usually every student owns a reasonably powerful mobile device that allows to be integrated in scenarios. One of the drawbacks of the fast evolution of reasonably powerful devices, is the
heterogeneity of that these kind of devices us ually bring with them. This paper provides an overview how rich mobile learning scenarios can be implemented platform independent on the basis of HTML5 and JavaScript. The paper presents a mobile learning application based on the principles of Situated Lea
rning entirely developed in HTML5. The paper also presents the results of tests performed with the application which were aimed at finding out the difference in performance users perceived when compared with the native desktop version of the
application and the added value that mobility introduces in learning activities.
The first robots are currently appearing on the consumer market. Initially they are targeted at rather simple applications such as entertainment and home convenience. For more complex areas, these robots will need to collaborate and interactively communicate with their human users, which requires appropriate man-machine interaction technologies and considerable cognitive abilities on the robot's side. Consumer acceptance will strongly depend on the integrated system. Thus, system integration and evaluation of the integrated system is becoming increasingly important. This paper describes our approach to construct a robotic assistance system. We present experience with an integrated technology demonstration and exposure of the integrated system to the public.
Coming out of the labs, the first robots are currently appearing on the consumer market. Initially they target rather simple application scenarios ranging from entertainment to home convenience. However, one can expect, that they will capture more complex areas soon. These robots will have a higher and higher level and a broad range of functional competence, and will collaborate and interactively communicate with their human users. All this requires considerable cognitive abilities on the robot’s side and appropriate man-machine interaction technologies. Apart from further development of individual functions and technologies it is crucial to build and evaluate fully integrated systems. This paper describes our approach to construct a robotic assistance system. We present experience with an integrated technology demonstration and the exposure of the integrated system to the public.
Magnesium ist das leichteste Metall, das im konstruktiven Leichtbau Anwendung findet. Zusätzlich ist Magnesium ein wichtiges Element in Aluminiumlegierungen, was den derzeit bedeutendsten Einsatzbereich darstellt. Die Gewinnung von primären Magnesiummetall aus verschiedenen Rohstoffen ist ein sehr energieintensiver Prozess, der vorwiegend in China stattfindet. Die für die Herstellung von einem Kilogramm metallischen Magnesium benötigte Endenergie beträgt zwischen 18 und 80 kWh, je nach eingesetztem Energieträger und Prozess.
Das Umschmelzen von sauberen Neuschrotten erfordert lediglich rund 1 kWh je kg Magnesiumlegierung. Dies verdeutlicht bereits, dass sich durch ein Recycling, im Vergleich zur Primärproduktion, erhebliche Energieeinsparungen erzielen lassen. Altschrotte aus Produkten am Ende ihres Nutzungszyklus werden gegenwärtig kaum innerhalb des Kreislaufs von Magnesiumlegierungen recycelt. Meist werden Magnesiumlegierungen gemeinsam mit der Aluminiumfraktion dem Recycling zugeführt und so im besten Fall als Legierungselement genutzt.
Im Rahmen dieser Arbeit werden die theoretischen Potenziale von Energie- und Treibhausgasemissionseinsparungen durch das Recycling von Magnesium-Altschrotten im Vergleich zum Primärmarkt einer AZ91D-Legierung untersucht. Mittels einer modellierten Ökobilanz werden die Einsparpotenziale für die Wirkungskategorien Treibhausgasemissionen (Global Warming Potential) sowie den kumulierten Energieaufwand (KEA) ermittelt.
Über die Modellierung und Ermittlung der Potenziale hinaus wurden mehrere Expert:inneninterviews geführt. Schlussfolgerungen aus diesen Gesprächen sind, dass die für ein geschlossenes Recycling nötige Technik zur Verfügung steht und gegenwärtig nicht gehobene Potenziale durch das Recycling bestehen. Hinsichtlich der wirtschaftlichen Rah-menbedingungen des Recyclings von Altschrotten wurden divergierende Einschätzungen festgestellt, wonach die geringen Mengen der Altschrotte hemmend, das gestiegene Preisniveau hingegen als fördernd für ein geschlossenes Recycling identifiziert wurden.
Building upon prior results, we present an alternative approach to efficiently classifying a complex set of 3D hand poses obtained from modern Time-Of-Flight-Sensors (TOF). We demonstrate it is possible to achieve satisfactory results in spite of low resolution and high noise (inflicted by the sensors) and a demanding outdoor environment. We set up a large database of pointclouds in order to train multilayer perceptrons as well as support vector machines to classify the various hand poses. Our goal is to fuse data from multiple TOF sensors, which observe the poses from multiple angles. The presented contribution illustrates that real-time capability can be maintained with such a setup as the used 3D descriptors, the fusion strategy as well as the online confidence measures are computationally efficient.
Touch versus mid-air gesture interfaces in road scenarios-measuring driver performance degradation
(2016)
We present a study aimed at comparing the degradation of the driver's performance during touch gesture vs mid-air gesture use for infotainment system control. To this end, 17 participants were asked to perform the Lane Change Test. This requires each participant to steer a vehicle in a simulated driving environment while interacting with an infotainment system via touch and mid-air gestures. The decrease in performance is measured as the deviation from an optimal baseline. This study concludes comparable deviations from the baseline for the secondary task of infotainment interaction for both interaction variants. This is significant as all participants are experienced in touch interaction, however have had no experience at all with mid-air gesture interaction, favoring mid-air gestures for the long-term scenario.
We present a light-weight real-time applicable 3D-gesture recognition system on mobile devices for improved Human-Machine Interaction. We utilize time-of-flight data coming from a single sensor and implement the whole gesture recognition pipeline on two different devices outlining the potential of integrating these sensors onto mobile devices. The main components are responsible for cropping the data to the essentials, calculation of meaningful features, training and classifying via neural networks and realizing a GUI on the device. With our system we achieve recognition rates of up to 98% on a 10-gesture set with frame rates reaching 20Hz, more than sufficient for any real-time applications.
The continuous evolution of learning technologies combined with the changes within ubiquitous learning environments in which they operate result in dynamic and complex requirements that are challenging to meet. The fact that these systems evolve over time makes it difficult to adapt to the constant changing requirements. Existing approaches in the field of Technology Enhanced Learning (TEL) are generally not addressing those issues and they fail to adapt to those dynamic situations. In this chapter, we investigate the notion of an adaptive and adaptable architecture as a possible solution to address these challenges. We conduct a literature survey upon the state of the art and state of practice in this area. The outcomes of those efforts result in an initial model of a Domain-specific architecture to tackle the issues of adaptability and adaptiveness. To illustrate these ideas, we provide a number of scenarios where this architecture can be applied or is already applied. Our proposed approach serves as a foundation for addressing future ubiquitous learning applications where new technologies constantly emerge and new requirements evolve.
The presented work formulates an framework in which early prediction of drivers lane change behavior is realized. We aim to build a representation of drivers lane change behavior in order to recognize and to predict driver's intentions as a first step towards a realistic driver model. In the test bed of the Institute of Neuroinformatik, based on the traffic simulator NISYS TRS 1, 10 individuals have driven in the experiments and they performed more then 150 lane change maneuvers. Lane-offset, distance to the front car and time to contact, were recorded. The acquired data was used to train - in parallel- a recurrent neural network, a feed forward neural network and a set of support vector machines. In the followed test drives the system was able of performing a lane change prediction time of 1.5 sec beforehand. The proposed approach describes a framework for lane-change detection and prediction, which will serve as a prerequisite for a successful driver model.
This paper presents an approach towards a mobile learning environment, which is flexible in terms of supported scenarios, supported devices and input channels. The approach makes use of existing and commonly used channels like SMS, Twitter or Face book to increase acceptance and ease-of-use of mobile devices in learning scenarios. Envisaged application scenarios are described along with technical details for their realization.
This paper describes the design and development stages of a web-based framework, aiming to support the creation of mobile applications within the context of mobile learning. The suggested approach offers the opportunity to deploy and execute these applications on mobile devices. This web-based solution additionally offers the possibility to visualize the data collected by the mobile applications in a web-browser. Despite previous research efforts carried out in this domain, few of the projects have addressed these processes from a purely web-based perspective. Currently, a prototype of an authoring tool for creating mobile data collection applications is already implemented. In order to integrate and validate this solution in everyday educational settings, we are collaborating with a network of high schools. On the basis of workshops with teachers we will carry out, refinements and requirements for further enhancements will be collected and will be used to guide our coming efforts.
Researchers have previously utilized the advantages of a design driven by well-being and intergenerational collaboration (IGC) for successful innovation. Unfortunately, scant information exists regarding barrier dimensions and correlated design solutions in the information systems (IS) domain, which can serve as a starting point for a design oriented toward well-being in an IGC system. Therefore, in this study, we applied the positive computing approach to guide our analysis in a systematic literature review and developed a framework oriented toward well-being for a system with a multi-generational team. Our study contributes to the IS community by providing five dimensions of barriers to IGC and the corresponding well-being determinants for positive system design. In addition, we propose further research directions to close the research gap based on the review outcomes.
In recent years, hardware for the production and consumption of virtual reality content has reached level of prices that make it affordable to everyone. Accordingly schools and universities are showing increased interest in implementations of virtual reality technologies for supporting their innovative educational activities. Hence, this paper presents a flexible architecture for supporting the development of virtual reality learning scenarios conveniently deployed for educational purposes. We also suggest an example of such
educational scenario for medical purposes deployable with the suggested architecture. In addition, we developed and used a questionnaire answered by 17 medical students in order to derive additional requirements for refining such scenarios. Then, we present these efforts while aiming at deployments usable also for additional domains. Finally, we summarize and mention aspects we will address
in our coming efforts while deploying such activities.
As service robotics research advances rapidly, availability of objective, reproducible test specifications and evaluation criteria and also of benchmarking is more and more felt to be desirable in the community. As a first step towards benchmarking, in this paper we propose a formalization of tests - exemplified for domestic grasp&place tasks. The underlying philosophy of our approach is to confront the robot system in a black-box manner with requirements of a “rational customer”, and characterize the performance of the system in an objective way by the outcomes of a test-suite tailored to this scenario. A formalized single test description consists of a clear and reproducible specification of the robot’s task and the full context on the one hand, and a number of figures which objectively characterize the test result on the other hand. We illustrate this methodology for the domestic assistance scenario.
Digital transformation is a process of digitizing the working and living environment in which people are at the center of digitization. In this paper, we present a personas-based guideline for system developers on how the humanization of digital transformation integrates into the design process. The proposed guideline uses the positive personas from the beginning as a basis for the transformation of the working environment into the digital form. We used the literature research as a preliminary study for the process of wellbeing-driven digital transformation design, consisting of questions for structuring the required information in the positive personas as well as a potential method that could be integrated into the wellbeing-based design process.
The virtual classroom continues to grow, but it is becoming more and more the norm, and it is fundamentally different from the vocational students at the Indonesian university. With the promised benefits of the virtual classroom, many challenges and difficulties come in the implementation. Although there are already successful design principles for virtual classrooms that support organizations in overcoming the challenges, the approach to implementing the design principles of virtual classroom at the vocational higher education in Indonesia is still lacking. In this study, we aim to answer the research gap and used the design sciences research by interviewing the lecturers to design the solutions. The proposed design approaches were implemented in a course and evaluated with students from two different groups. Overall, the evaluation of the proposed approaches shows1 significant results as an indicator of the benefits of the implementation of a virtual classroom for vocational students in Indonesia.
Electro-magnetic acoustic transducers (EMATs) are intended as non-contact and non-destructive ultrasound transducers for metallic material. The transmitted intensities from EMATS are modest, particularly at notable lift off distances. Some time ago a concept for a “coil only EMAT” was presented, without static magnetic field. In this contribution, such compact “coil only EMATs” with effective areas of 1–5 cm2 were driven to excessive power levels at MHz frequencies, using pulsed power technologies. RF induction currents of 10 kA and tens of Megawatts are applied. With increasing power the electroacoustic conversion efficiency also increases. The total effect is of second order or quadratic, therefore non-linear and progressive, and yields strong ultrasound signals up to kW/cm2 at MHz frequencies in the metal. Even at considerable lift off distances (cm) the ultrasound can be readily detected. Test materials are aluminum, ferromagnetic steel and stainless steel (non-ferromagnetic). Thereby, most metal types are represented. The technique is compared experimentally with other non-contact methods: laser pulse induced ultrasound and spark induced ultrasound, both damaging to the test object’s surface. At small lift off distances, the intensity from this EMAT concept clearly outperforms the laser pulses or heavy spark impacts.
Efficient and reliable onsite inspection methods are gaining importance as the construc-tion of PV power plants is expanding. For large PV installations, time- and cost-efficient failure detection is essential for optimized operation and maintenance. For this purpose, various optical methods as Infrared thermography (IR), Electroluminescence (EL), Pho-toluminescence (PL) and Ultraviolet Fluorescence (UVF) are employed and under con-stant development. For each method, the camera, and eventually the light source, can be handheld, or mounted on a drone, also called unmanned aircraft vehicle (UAV), to achieve higher throughputs.
IR is the most widely used optical onsite PV inspection method, as many defects can be detected by the thermal radiation (heating) of the defect component. EL and PL reveal further information on the electrical behaviour of the Si-waver. They are also widely used and take the role of a complement to IR, showing electrically active/inactive areas of the semiconductor. On the other hand, UVF focuses on the degradation of the polymeric encapsulant of the Si-cell, most commonly consisting of EVA (ethylene-vinyl acetate). The degradation of the encapsulant can lead to its discoloration, also called yellow-ing/browning, which decreases the transmittance of visual light. UVF patterns can show this yellowing as well as humidity and oxygen entrances, which can lead to effects of corrosion. Both mechanisms (discoloration and corrosion) decrease the performance of the PV cell. The discoloration cannot be directly observed on IR or EL images, as the encapsulant is neither a heat source nor electroconductive. Using IR imagery, severe discoloration might be observed indirectly, as the reduced optical transmittance leads to changes in heat transfer mechanisms concerning the cell and the encapsulant.
Similarly, as long as corrosion does not lead to inactive cell areas or heating, it most likely will not be spotted using EL, PL or IR. So, UVF can fill the niche of inspecting the state of the encapsulant and detecting its defects due to climate impacts in early stages.
While a high number of studies on IR, EL, PL and some on UVF were performed in Europe and the USA, there are not yet many studies about the application of these tech-niques in South America (i.e., in Brazil). UVF mainly depends on climate factors (irradi-ation, temperature, humidity) and the operation time/”age” of the module. The UVF im-agery method has not yet been tested in climate and system conditions of Brazil. Fur-thermore, systems in Brazil are more recently installed. All this can affect differences in the results of UVF imagery applied in Europe, the USA and Brazil.
The present work focuses on the application of UVF imaging on PV power plants in Bra-zil, the creation of an experimental setup and the proposal of proceedings for the data analysis of the acquired images. The aim is to propose a method that is suitable for large-scale inspection.
Rapid digital transformation is taking place due to the COVID-19 pandemic, forcing organisations and higher educational institutions to change their working and learning culture. This study explores the challenges of rapid digital transformation arising during the pandemic in the higher education context. This research used the Q-methodology to understand the nine challenges that higher education encountered, perceived differently as four main patterns: (1) Digital-nomad enterprise; (2) Corporate-collectivism; (3) Well-being-oriented; and (4) Pluralistic. This study broadens the current understanding of digital transformation, especially in higher education. The nine challenges and four patterns of transformation actors serve as a starting point for organisations in supporting technological choice and strategic interventions, based on individual, group, and organisational behavioural levels. Moreover, five propositions, based on the competing concerns of these challenges, establish a framework for comprehending the ecosystem that enables rapid digital transformation. Strategies, prerequisites, and key factors during the (digital) technology development process benefit the cyber-society ecosystem. As a practical contribution, Q-methodology was used to investigate perspectives on digitalisation challenges during the pandemic.
Social networking sites (SNSs) are an integral part of our daily life. With the evermore increasing appearance of SNSs, their users spend considerable time producing of different forms everyday (e.g. text, videos, photos, links, etc.) or browsing the varieties of contents in different SNSs. In this paper, we propose an architectural perspective on a framework that provides a unified environment through which users can produce and browse different contents of SNSs from one place.
Die Digitalisierung des deutschen Gesundheitswesens ist im direkten Vergleich zu anderen Branchen und Gesundheitswesen deutlich im Rückstand. Ursachen für diesen Rückstand sollten identifiziert werden, um aus den gefundenen Faktoren Handlungsempfehlungen zu entwickeln, die dabei helfen sollen künftige Digitalisierungsprojekte effizienter zu gestalten. Zur Identifizierung wurde zunächst eine unstrukturierte Literaturrecherche durchgeführt, gefolgt von Experteninterviews, die den eigentlichen Kern der Arbeit darstellen. Die ausgewählten Probanden stellen Beteiligten des Projektes elektronische Arbeitsunfähigkeitsbescheinigung dar, dessen Projektverlauf evaluiert wurde, um aus den Herausforderungen zu lernen.
Untersuchung des Einflusses von Längsrissen in Drähten auf die Impedanz eines Wirbelstromsensors
(2012)
Gestures are part of the interaction between humans and are currently getting more and more popular in the field of Human-Machine Interaction (HMI). First systems with mid-air gesture control are available in the automotive field of application. But it is still an open question which gestures are intuitive for the users, standards do not exist. In this paper we present a 2-step user study on expectations on touchless gestures in vehicles as part of a participatory design process.
For highly automated vehicles (AVs), new interaction concepts need to be developed. Even in AVs, the driver might want to intervene and override the automation from time to time. To create the possibility of control, we explore vehicle control through maneuver-based interventions (MBI). Thereby, we focus on explicit, contact-less interaction, which could be beneficial in future AV designs, where the driver is not necessarily bound to classical controls. We propose a set of freehand gestures and keywords for voice control derived in a user-centered design process. Further, we discuss properties, applicability and user impressions of both interaction modalities. Voice control seems to be an efficient way to select a maneuver and free-hand gestures could be used, if voice channel is blocked, e.g., through conversation with passengers.
Recommender systems have become an important application domain related to the development of personalized mobile services. Thus, various recommender mechanisms have been developed for filtering and delivering relevant information to mobile users. This paper presents a rich context model to provide the relevant content of news to the current context of mobile users. The proposed rich context model allows not only providing relevant news with respect to the user’s current context but, at the same time, also determines a convenient representation format of news suitable for mobile devices.
In this paper we present an approach for People-to-People recommendations based on a Rich Context Model (RCM). We consider personal user information as contextual information used for our recommendations. The evaluation of our recommendation approach was performed on a social network of students. The obtained results do show a significant increase in performance while, at the same time, a slight increase in quality in comparison to a manual matching process. The proposed approach is flexible enough to handle different data types of contextual information and easy adaptable to other recommendation domains.
In this paper we present an approach for contextual big data analytics in social networks, particularly in Twitter. The combination of a Rich Context Model (RCM) with machine learning is used in order to improve the quality of the data mining techniques. We propose the algorithm and architecture of our approach for real-time contextual analysis of tweets. The proposed approach can be used to enrich and empower the predictive analytics or to provide relevant context-aware recommendations.