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Während in anderen Staaten die Überwachung von Verkehr und Nachbarschaft mit Videokameras weit verbreitet ist, wird in Deutschland derzeit über im Auto angebrachte Videokameras, die das Verkehrsgeschehen um das Fahrzeug herum aufnehmen, diskutiert und gestritten. Diese werden in der Regel „neudeutsch“ Dashcam genannt (dash = Armaturenbrett). Auch die Bezeichnungen „Car-Cam“ oder „On-Board-Kamera“, selbst „CrashCam“ finden sich. Verbreitung finden die Filmchen dieser Dashcams derzeit in erster Linie bei Diensten wie Youtube, wenn ein Fahrer meint, besonders spektakuläre Szenen mitgeschnitten zu haben (z.B. ein quer über die Autobahn abstürzendes Flugzeug) oder sich besonders über andere Fahrer ärgert bzw. lustig machen möchte. Der Beitrag setzt sich mit der datenschutzrechtlichen Zulässigkeit derartiger Einrichtungen auseinander. Nach einer kurzen Vorbemerkung zur Reichweite der hier vorgestellten Beurteilung über Dashcams hinaus (I.) wird zunächst der Stand der Rechtsprechung speziell zur Zulässigkeit und Verwertbarkeit von Dashcam-Aufnahmen aufgezeigt (II.). Sodann wird die Verwendung von Dashcams einer sorgfältigen datenschutzrechtlichen Analyse unterzogen (III.), aus der nur das Fazit (IV.) gezogen werden kann, dass derartige Aufzeichnungen öffentlichen Raumes regelmäßig unzulässig sind.
This paper presents a new approach for the teaching of competence in additive manufacturing to engineering students in product development. Particularly new to this approach is the combination of the students' autonomous assembly and commissioning of a 3D-printer, and the independent development of guidelines for this new technology regarding the design of components. This way the students will be able to gain first practical experiences with the data preparation, the additive manufacturing process itself and also the required post-treatment of the 3D-printed parts. To allow the students a significantly deeper insight into the functioning of 3D-printing, the workshop Rapid Prototyping developed a new approach in the course of which the students first assemble a construction kit for a 3D-printer themselves and then commission the printer. This enables the students to gain a better understanding of the functionality and configuration of additive manufacturing. In a next step, the students used the 3D-printers they constructed themselves to produce components which they take from a database. Finally, the experiences of the students in the course of the workshop will be evaluated to review the effectiveness of the new approach.
Widerruf beim Anwaltsvertrag
(2015)
Who is Who? Joseph Fourier
(2015)
Was ist eine Theorie?
(2015)
Die vorliegende Arbeit beschäftigt sich mit der Wahrnehmung von Websites im One-Page-Design und der Verbesserung der User Experience mit Hilfe von Blickaufzeichnung und weiteren Methoden.
Für ein Unternehmen ist eine Website mittlerweile ein zentrales Marketinginstrument. Eine gute Umsetzung der Website ist maßgeblich am Unternehmenserfolg beteiligt.
Eine bedeutende Rolle für eine Website spielt das Webdesign. Dies beeinflusst entscheidend, ob das Interesse des Nutzers geweckt wird und er auf der Website verweilt oder diese direkt wieder verlässt. Doch das Webdesign verändert sich laufend. Ein neuer Trend ist die Website im One-Page-Design. Diese bietet neue Möglichkeiten der Gestaltung, stellt Webdesigner jedoch auch bei der Umsetzung vor neue Herausforderungen. Mit der vorliegenden Arbeit sollen deshalb Websites im One-Page-Design hinsichtlich ihrer Wirkung auf den Nutzer analysiert werden. Zu diesem Zweck werden mit ausgewählten Probanden User Experience Tests durchgeführt, die Aufschluss darüber geben sollen, wie die Zielgruppe mit der Website interagiert. Durch die Analyse der gewonnenen Daten und die daraus abgeleiteten Handlungsempfehlungen kann die User Experience von Websites im One-Page-Design gesteigert werden. Neben der Eyetracking-Methode (Blickaufzeichnung) wird die Think Aloud-Methode, der Interview-Leitfragen sowie die Mimikmessung eingesetzt.
Zeitungsverlage haben jahrzehntelang in einem sehr stabilen Marktumfeld agiert, sodass die Kunst darin bestand, das Umfeld möglichst weiterhin konstant zu halten und die bestehenden Märkte und Produkte zu optimieren. Die neuen Medien- und Produktformen, die in dieser Zeit im Publikums- und Werbemarkt aufkamen, wurden bei den lokalen und regionalen Verlagen in das eigene Angebotsspektrum integriert, sodass am Ende im Regelfall ein oftmals kleiner, aber hochprofitabler Medienkonzern ins Internetzeitalter eintrat. Hier kommen nun zunehmend Anforderungen an digitale Geschäftsmodelle auf, die neue Geschäftsmodelle erfordern, die skalierbar sind.
Renommierte Autoren aus Wissenschaft und Praxis zeigen die Wandlung vom Zeitungsverlag zum crossmedialen Dienstleister der Region auf. Dieser produziert und bietet als Medienhaus alle relevanten Mediengattungen (digitale Produkte, E-Commerce, Services, Sonderprodukte aus dem Medienbereich) an. Dabei werden die Anforderungen an die einzelnen Verlagsfunktionen (Redaktion, Vertrieb, Marketing, Anzeigen) genauso beschrieben wie die neuen Ansprüche an die Managementkapazitäten und Organisationsstrukturen im integrierten Medienhaus. Der Verknüpfung der unterschiedlichen Geschäftsfelder kommt eine besondere Bedeutung zu, um Synergien besser zu realisieren. Auch die Unterschiede in der Umsetzung von Finanzierungsmodellen durch Vertriebs- und Werbeerlöse bei digitalen Produkten werden beleuchtet.
Im Buch "Visualisiere deine Welt! Ein Workbook für visuelle Notizen" erlernt der Leser in den ersten drei Teilen Schritt für Schritt, was visuelle Notizen sind und welchen Vorteil sie gegenüber rein textbasierten Notizen haben sowie aus welchen Elementen sie sich zusammensetzen. Anwendung finden visuelle Notizen beim Kommunizieren mit anderen, um sich visuell verständlich zu machen. Sie helfen aber auch dabei, Lösungen für Probleme zu finden, Ideen zu entwickeln und letztendlich bedeutsame Inhalte visuell zu dokumentieren. Im letzten Teil des Workbooks hat der Leser die Möglichkeit, sein erlerntes Wissen in zahlreichen Übungen anzuwenden.
A 2D-separation of 16 polyaromatic hydrocarbons (PAHs) according to the Environmental Protecting Agency (EPA) standard was introduced. Separation took place on a TLC RP-18 plate (Merck, 1.05559). In the first direction, the plate was developed twice using n-pentane at −20°C as the mobile phase. The mixture acetonitrile-methanol-acetone-water (12:8:3:3, v/v) was used for developing the plate in the second direction. Both developments were carried out over a distance of 43 mm. Further on in this publication, a specific and very sensitive indication method for benzo[a]pyrene and perylene was presented. The method can detect these hazardous compounds even in complicated PAH mixtures. These compounds can be quantified by a simple chemiluminescent reaction with a limit of detection (LOD) of 48 pg per band for perylene and 95 pg per band for benzo[a]pyrene. Although these compounds were separated from all other PAHs in the standard, a separation of both compounds was not possible from one another. The method is suitable for tracing benzo[a]pyrene and/or perylene. The proposed chemiluminescence screening test on PAHs is extremely sensitive but may indicate a false positive result for benzo[a]pyrene.
Towards a gamification of industrial production: a comparative study in sheltered work environments
(2015)
Using video game elements to improve user experience and user engagement in non-game applications is called "gamification". This method of enriching human-computer interaction has been applied successfully in education, health and general business processes. However, it has not been established in industrial production so far.
After discussing the requirements specific for the production domain we present two workplaces augmented with gamification. Both implementations are based on a common framework for context-aware assistive systems but exemplify different approaches: the visualization of work performance is complex in System 1 and simple in System 2.
Based on two studies in sheltered work environments with impaired workers, we analyze and compare the systems' effects on work and on workers. We show that gamification leads to a speed-accuracy-tradeoff if no quality-related feedback is provided. Another finding is that there is a highly significant raise in acceptance if a straightforward visualization approach for gamification is used.
Chronic insomnia is defined by difficulties in falling asleep, maintaining sleep, and early morning awakening, and is coupled with daytime consequences such as fatigue, attention deficits, and mood instability. These symptoms persist over a period of at least 3 months (Diagnostic and Statistical Manual 5 criteria). Chronic insomnia can be a symptom of many medical, neurological, and mental disorders. As a disorder, it incurs substantial health-care and occupational costs, and poses substantial risks for the development of cardiovascular and mental disorders, including cognitive deficits. Family and twin studies confirm that chronic insomnia can have a genetic component (heritability coefficients between 42% and 57%), whereas the investigation of autonomous and central nervous system parameters has identified hyperarousal as a final common pathway of the pathophysiology, implicating an imbalance of sleep–wake regulation consisting of either overactivity of the arousal systems, hypoactivity of the sleep-inducing systems, or both. Insomnia treatments include benzodiazepines, benzodiazepine-receptor agonists, and cognitive behavioural therapy. Treatments currently under investigation include transcranial magnetic or electrical brain stimulation, and novel methods to deliver psychological interventions.
The Effect of Gamification on Emotions - The Potential of Facial Recognition in Work Environmentsns
(2015)
Gamification means using video game elements to improve user experience and user engagement in non-game services and applications. This article describes the effects when gamification is used in work contexts. Here we focus on industrial production. We describe how facial recognition can be employed to measure and quantify the effect of gamification on the users’ emotions.
The quantitative results show that gamification significantly reduces both task completion time and error rate. However, the results concerning the effect on emotions are surprising. Without gamification there are not only more unhappy expressions (as to expect) but surprisingly also more happy expressions. Both findings are statistically highly significant.
We think that in redundant production work there are generally more (negative) emotions involved. When there is no gamification happy and unhappy balance each other. In contrast gamification seems to shift the spectrum of moods towards “relaxed”. Especially for work environments such a calm attitude is a desirable effect on the users. Thus our findings support the use of gamification.
Im Berufsbereich Medien existieren innerhalb einer Berufsuntergruppe die duale Ausbildung zur/zum Mediengestalter/-in Digital und Print sowie die vollzeitschulische Ausbildung zur/zum staatlich-geprüften Grafikdesigner/-in. In der vorliegenden Arbeit werden anhand dieser beiden Ausbildungsberufe die Ausbildungsformen verglichen, deren Stellenwert beleuchtet sowie die Vor- und Nachteile analysiert. Hierfür werden zunächst die theoretischen Hintergründe erarbeitet und die verschiedenen Perspektiven untersucht. Dieser Teil der Arbeit bildet dann die Basis zur Erstellung konkreter Fragen, anhand derer mit einer geeigneten Forschungsmethode empirische Daten erhoben werden sollen. Diese sollen im Anschluss ausgewertet, analysiert und interpretiert werden um möglichst präzise die Forschungsfrage beantworten zu können.
With major intellectual properties there is a long tradition of cross-media value chains -- usually starting with books and comics, then transgressing to film and TV and finally reaching interactive media like video games. In recent years the situation has changed: (1) smaller productions start to establish cross media value chains; (2) there is a trend from sequential towards parallel content production. In this work we describe how the production of a historic documentary takes a cross media approach right from the start. We analyze how this impacts the content creation pipelines with respect to story, audience and realization. The focus of the case study is the impact on the production of a documentary game. In a second step we reflect on the experiences gained so far and derive recommendations for future small-scale cross media productions.
Sicher funken mit 2,45 GHz
(2015)
Eine repräsentative Studie mit 2.400 deutschen Arbeitnehmern zeigt, dass Mitarbeiter seltener krank werden, wenn sie sich an ihr Unternehmen gebunden fühlen. Die Studie offenbart auch, dass die Intensität des Commitment maßgeblich von fünf Einflussfaktoren abhängt. Die Kenntnis dieser Faktoren ermöglicht es Personalmanagern, Mitarbeiter gezielter an das Unternehmen zu binden, um so den Krankenstand positiv zu beeinflussen.
Ripple: Overview and Outlook
(2015)
Ripple is a payment system and a digital currency which evolved completely independently of Bitcoin. Although Ripple holds the second highest market cap after Bitcoin, there are surprisingly no studies which analyze the provisions of Ripple.
In this paper, we study the current deployment of the Ripple payment system. For that purpose, we overview the Ripple protocol and outline its security and privacy provisions in relation to the Bitcoin system. We also discuss the consensus protocol of Ripple. Contrary to the statement of the Ripple designers, we show that the current choice of parameters does not prevent the occurrence of forks in the system. To remedy this problem, we give a necessary and sufficient condition to prevent any fork in the system. Finally, we analyze the current usage patterns and trade dynamics in Ripple by extracting information from the Ripple global ledger. As far as we are aware, this is the first contribution which sheds light on the current deployment of the Ripple system.
Rechtliche Dimension des Journalismus: Redaktionelle Verantwortung und User Generated Content
(2015)
Journalismus wandelt sich durch die Einbeziehung von User Generated Content. Dies hat nicht nur publizistische Folgen, sondern führt auch zu Problemen im Bereich der medienrechtlichen Verantwortung für die so publizierten Inhalte. Vor allem urheber- und persönlichkeitsrechtlichen Fragen sind für neue digitale Produkte zu prüfen. Insgesamt zeigt sich auch aus rechtlicher Sicht, dass eine Kombination unter Einbeziehung klassischer journalistischer Strukturen hilfreich ist, während rein von anonymen Nutzern gestaltete Produkte erhebliche Risiken bergen.
In dieser Thesis werden Arbeitsverfahren zur Produktion und Umsetzung von Soundeffekten und Musik im Bereich On-Air Sound Design im Radio beschrieben und anhand von Bespielen erklärt. Diese Verfahren werden am Beispiel von In- halten für die Imaging Libraries der Firma Benztown demonstriert. Das Unter- nehmen versorgt bereits seit 8 Jahren mehr als 1900 Radiostationen mit kreativem Inhalt und repräsentiert somit den Stand Der Technik im Bereich Radio Imaging. Vorerst werden die Profile, der von der Library angebotene Formate, analysiert, um ein besseres Verständnis für die einzelnen Bestandteile zu schaffen und darauf aufbauend detailliert erläutert. Dabei beziehen sich die Beschreibungen auf den US-Markt und gelten somit nicht für den deutschen Markt. Um eine ersichtliche Darstellung der Konzeption zu erreichen, werden anschließend alle definierten Methoden und Verfahren in der Praxis realisiert und protokoliert. Die Untersuchung der Eigenschaften und Lösungsansätze wird ausführlich be- schrieben und anhand von literarisch/webbasierten Quellen belegt, verglichen und gegebenenfalls aktualisiert. Auch die technischen Aspekte der Produktion sind bei der Ausarbeitung von großer Bedeutung und werden daher im Laufe dieser Arbeit kontinuierlich berücksichtigt und ausführlich erklärt. Dabei verzweigen sich diese in Spezifikation der angewandten Werkzeuge und Anwendung effizienter Produktionstechniken.
Das Resultat dieser Bachelor Arbeit setzt sich zusammen aus der Analyse und Konzeption von Imaging Libraries und die Umsetzung deren Inhalts, so wie die praktische Anwendung der gewonnenen Erkenntnisse. Dabei wird systematisch vorgegangen um eine effiziente Planung, Realisierung und Bearbeitung von Effekten und Musik zu erreichen.
We present a 3D simulation approach utilising the diffuse interface representation of the phase-field method combined with a heat transfer equation to analyse the thermal conductivity in air-filled aluminium foams with complex cellular structures of different porosity. Algorithmic methods are introduced to create synthetic open-cell foam structures and to compute the thermal conductivity by means of phase-field modelling. A material law for the effective thermal conductivity is derived by determining the appropriate exponent depending on the relative density in the system. The results are compared with the thermal conductivity in massive aluminium and in pure air.
We report the use of the Raman spectral information of the chemical compound toluene C7H8 as a reference on the analysis of laboratory-prepared and commercially acquired gasoline-ethanol blends. The rate behavior of the characteristic Raman lines of toluene and gasoline has enabled the approximated quantification of this additive in commercial gasoline-ethanol mixtures. This rate behavior has been obtained from the Raman spectra of gasoline-ethanol blends with different proportions of toluene.
All these Raman spectra have been collected by using a self-designed, frequency precise and low-cost Fourier-transform Raman spectrometer (FT-Raman spectrometer) prototype. This FT-Raman prototype has helped to accurately confirm the frequency position of the main characteristic Raman lines of toluene present on the different gasoline-ethanol samples analyzed at smaller proportions than those commonly found in commercial gasoline-ethanol blends. The frequency accuracy validation has been performed by analyzing the same set of toluene samples with two additional state-of-the-art commercial FT-Raman devices. Additionally, the spectral information has been contrasted, with highly-correlated coefficients as a result, with the values of the standard Raman spectrum of toluene.
Die Ausarbeitung der Bachelor-Thesis zum Thema persuasive Kommunikation umfasst im Wesentlichen einen Überblick über die Ursprünge, die Entwicklungsstadien und die heutigen Anwendungsbereiche der Persuasion.
Persuasive Kommunikation zeigt sich bewusst oder unbewusst als stetiger Begleiter des Alltags, der Politik, der Werbung und der Öffentlichkeitsarbeit.
Die verschiedenen aufgeführten Forschungsansätze bestätigen die enge Verbindung zwischen persuasiver Kommunikation und Rhetorik. Aber auch die Abhängigkeit der einzelnen Kommunikationsaspekte− Kommunikator, Rezipient, Botschaft und Medium− erwiesen sich als Kontinuum der Persuasion. Die einzelnen Schwerpunkte und Charakteristika dieser Kommunikationsaspekte unterscheiden sich je nach Forschungsansatz und Auslegungsweise. Grundsätzlich ist das Involvement der Kommunikationsparteien, speziell das des Rezipienten, von essentieller Bedeutung für den persuasiven Kommunikationsprozess. Dieser Faktor zeigt sich vor allem in der Anwendung von Persuasion im aktuellen Kontext, beispielsweise in der Werbekommunikation.
Schlussfolgernd ist festzustellen, dass persuasive Kommunikation aufgrund der Medialisierung einen starken Wandel erlebt, der sich primär in der Rezeptionsweise und -affinität des Rezipienten widerspiegelt. Dies hat verstärkend Auswirkung auf alle anderen Kommunikationsbestandteile und beeinflusst die Aufbereitung und Inszenierung des Inhalts, die Wahl des Medienkanals und auch die Fähigkeiten des Kommunikators.
Soccer simulation league is one of the founding leagues of RoboCup. In this paper we discuss the past, present and planned future achievements and changes. Also we summarize the connections and inter-league achievements of this league and provide an overview of the community contributions that made this league successful.
Concussions in sports and during recreational activities are a major source of traumatic brain injury in our society. This is mainly relevant in adolescence and young adulthood, where the annual rate of diagnosed concussions is increasing from year to year. Contact sports (e.g., ice hockey, American football, or boxing) are especially exposed to repeated concussions. While most of the athletes recover fully from the trauma, some experience a variety of symptoms including headache, fatigue, dizziness, anxiety, abnormal balance and postural instability, impaired memory, or other cognitive deficits. Moreover, there is growing evidence regarding clinical and neuropathological consequences of repetitive concussions, which are also linked to an increased risk for depression and Alzheimer’s disease or the development of chronic traumatic encephalopathy. With little contribution of conventional structural imaging (computed tomography (CT) or magnetic resonance imaging (MRI)) to the evaluation of concussion, nuclear imaging techniques (i.e., positron emission tomography (PET) and single-photon emission computed tomography (SPECT)) are in a favorable position to provide reliable tools for a better understanding of the pathophysiology and the clinical evaluation of athletes suffering a concussion.
Due to the development of the social web, the traditional word-of-mouth has obviously spread into this widely-used medium and developed. Products, services, brands, and enterprises are still the main topics of word-of-mouth. However, senders and recipients are no longer restricted to their circle of acquaintances. Every consumer who has access to the Internet is able to consume and publish reviews.
This paper deals with the importance which is awarded to the word-of-mouth on the social web referring to B2C markets. First, consumers and their motives for spreading and consuming word-of-mouth are examined since they, as purchasers, determine the success of enterprises substantially. Afterwards, the paper focuses on the importance of word-of-mouth for enterprises by revealing potential opportunities and risks.
To achieve this aim, the paper is based on secondary research and therefore consults a wide range of literature. Furthermore, the results rely on studies, statistics, and consumer surveys.
It turns out that word-of-mouth on the social web supports consumers in satisfying a variety of needs. Particularly when it comes to decision and opinion making processes consumers seek advice from the Internet community. This also implicates the remarkable importance of word-of-mouth for enterprises, which is illustrated by the potential opportunities and risks.
Since the extent of these opportunities and risks cannot generally be determined for all enterprises, it is necessary for every single enterprise to identify the consequences of these opportunities and risks individually by using a monitoring. For this reason some recommendations are attached, which help handling the word-of-mouth on the social web.
Phosphate-based inorganic–organic hybrid nanoparticles (IOH-NPs) with the general composition [M]2+[Rfunction(O)PO3]2– (M = ZrO, Mg2O; R = functional organic group) show multipurpose and multifunctional properties. If [Rfunction(O)PO3]2– is a fluorescent dye anion ([RdyeOPO3]2–), the IOH-NPs show blue, green, red, and near-infrared fluorescence. This is shown for [ZrO]2+[PUP]2–, [ZrO]2+[MFP]2–, [ZrO]2+[RRP]2–, and [ZrO]2+[DUT]2– (PUP = phenylumbelliferon phosphate, MFP = methylfluorescein phosphate, RRP = resorufin phosphate, DUT = Dyomics-647 uridine triphosphate). With pharmaceutical agents as functional anions ([RdrugOPO3]2–), drug transport and release of anti-inflammatory ([ZrO]2+[BMP]2–) and antitumor agents ([ZrO]2+[FdUMP]2–) with an up to 80% load of active drug is possible (BMP = betamethason phosphate, FdUMP = 5′-fluoro-2′-deoxyuridine 5′-monophosphate). A combination of fluorescent dye and drug anions is possible as well and shown for [ZrO]2+[BMP]2–0.996[DUT]2–0.004. Merging of functional anions, in general, results in [ZrO]2+([RdrugOPO3]1–x[RdyeOPO3]x)2– nanoparticles and is highly relevant for theranostics. Amine-based functional anions in [MgO]2+[RaminePO3]2– IOH-NPs, finally, show CO2 sorption (up to 180 mg g–1) and can be used for CO2/N2 separation (selectivity up to α = 23). This includes aminomethyl phosphonate [AMP]2–, 1-aminoethyl phosphonate [1AEP]2–, 2-aminoethyl phosphonate [2AEP]2–, aminopropyl phosphonate [APP]2–, and aminobutyl phosphonate [ABP]2–. All [M]2+[Rfunction(O)PO3]2– IOH-NPs are prepared via noncomplex synthesis in water, which facilitates practical handling and which is optimal for biomedical application. In sum, all IOH-NPs have very similar chemical compositions but can address a variety of different functions, including fluorescence, drug delivery, and CO2 sorption.
Combined heat and power production (CHP) based on solid oxide fuel cells (SOFC) is a very promising technology to achieve high electrical efficiency to cover power demand by decentralized production. This paper presents a dynamic quasi 2D model of an SOFC system which consists of stack and balance of plant and includes thermal coupling between the single components. The model is implemented in Modelica® and validated with experimental data for the stack UI-characteristic and the thermal behavior. The good agreement between experimental and simulation results demonstrates the validity of the model. Different operating conditions and system configurations are tested, increasing the net electrical efficiency to 57% by implementing an anode offgas recycle rate of 65%. A sensitivity analysis of characteristic values of the system like fuel utilization, oxygen-to-carbon ratio and electrical efficiency for different natural gas compositions is carried out. The result shows that a control strategy adapted to variable natural gas composition and its energy content should be developed in order to optimize the operation of the system.
Die traditionellen Geschäftsmodelle der Zeitungsverlage beruhen auf der Werbevermarktung von Anzeigen und Beilagen und dem direkten Erlösmodell für journalistische Inhalte durch Abonnement, bzw. Einzelverkaufserlöse. Diese Geschäftsmodelle verändern sich zugunsten neuer nicht-journalistischer digitaler Geschäftsmodelle, deren Zukunftsfähigkeit jedoch in vielen Fällen noch nicht bewiesen ist.
Dieses Kapitel beschreibt den technologischen, politischen und wirtschaftlichen Hintergrund, vor dem die derzeitigen Veränderungen der deutschen Zeitungslandschaft zu bewerten sind. Das Phänomen der Konvergenz, d. h. unterschiedliche Entwicklungslinien bewegen sich aufeinander zu, können wir in ganz unterschiedlichen gesellschaftlichen Bereichen immer wieder feststellen. Positionen politischer Parteien konvergieren, Hochschulgattungen nähern sich einander an und ebenso die Mediengattungen in Form der „Medienkonvergenz“.
Instabilities of the interface between two thin liquid films under DC electroosmotic flow are investigated using linear stability analysis followed by an asymptotic analysis in the long-wave limit. The two-liquid system is bounded by two rigid plates which act as substrates. The Boltzmann charge distribution is considered for the two electrolyte solutions and gives rise to a potential distribution in these liquids. The effect of van der Waals interactions in these thin films is incorporated in the momentum equations through the disjoining pressure. Marginal stability and growth rate curves are plotted in order to identify the thresholds for the control parameters when instabilities set in. If the upper liquid is a dielectric, the applied electric field can have stabilizing or destabilizing effects depending on the viscosity ratio due to the competition between viscous and electric forces. For viscosity ratio equal to unity, the stability of the system gets disconnected from the electric parameters like interface zeta potential and electric double-layer thickness. As expected, disjoining pressure has a destabilizing effect, and capillary forces have stabilizing effect. The overall stability trend depends on the complex contest between all the above-mentioned parameters. The present study can be used to tune these parameters according to the stability requirement.
Diese Abschlussarbeit ist Resultat einer studiengangs-übergreifenden Zusammenarbeit von Valerie Heinlein (Medien und Informationswesen, B.Sc.) und Nils Kreuter (Medientechnik/Wirtschaft plus, B.Eng.)innerhalb der Fakultät Medien und Informationswesen der Hochschule Offenburg.
Im Rahmen dieser Bachelorarbeit wird ein crossmediales Corporate Design für das gemeinnützige Kinderzentrum PfiFf erstellt. Das Projekt kam auf Initiative der Leiterinnen des Kinderzentrums PfiFf zustande. Die Intention ihrerseits war es, mithilfe einer
studentischen Zusammenarbeit den Bekanntheitsgrad des Kinderzentrums durch eine Neukonzeption der medialen Außendarstellung zu erweitern.Die Entscheidung zur Durchführung dieser Abschlussarbeit geht mit dem Wunsch einher,einen generell gemeinnützigen Beitrag zu leisten, sowie aufgrund der gegebenen Möglichkeit, die im Rahmen des Studiums erlernten Fachkenntnisse innerhalb eines
realen Projektes praktisch anzuwenden.
Die im Zuge des Studiums erworbenen Kompetenzen aus den Bereichen Mediengestaltung, Medientechnik, Betriebswirtschaftslehre und Informatik bilden die Grundlage zur Durchführung dieser interdisziplinären Abschlussarbeit. Der praktische Anteil der vorliegenden Arbeit wird in ständiger und schrittweiser Abstimmung
mit den Leiterinnen des Kinderzentrums PfiFf – Sandra Mattes und Michaela Stier – ausgeführt, sodass die gesetzten Ziele in beidseitigem Einverständnis erreicht
werden können.
Instagram-Marketing: Erfolgsfaktoren und Handlungsempfehlungen am Beispiel der Kosmetikindustrie
(2015)
Das Ziel dieser Arbeit lag darin, Faktoren, die den Erfolg eines Instagram-Auftritts von Kosmetik produzierenden oder vertreibenden Unternehmen aus dem deutsch-sprachigen Raum steigern, zu ermitteln und auf Grundlage der Ergebnisse Handlungs-empfehlungen auszusprechen. Im Zuge dessen wurden sieben qualitative Befragungen von Experten durchgeführt und anschließend mit Hilfe der zusammen-fassenden Inhaltsanalyse nach Mayring ausgewertet. Aus der empirischen Studie geht hervor, dass Instagram bereits jetzt eine große Rolle im Social-Media-Mix einnimmt und Unternehmen primär Ziele des Brandings und der Markenrepräsentation auf Instagram verfolgen. Desweiteren konnten mit Hilfe der leitfadengestützten Experteninterviews 15 Faktoren identifiziert werden, die positiven Einfluss auf das Instagram-Marketing ausüben: Persönlichkeit, Qualität, Authentizität, Aktualität, Kanalmix, Hashtags, Videos, die Verknüpfung mit anderen Unternehmensbereichen, Transparenz, Relevanz, Influencer-Relations, Community, Bestätigung und Management. Als am bedeutend-sten haben sich die Punkte Persönlichkeit, Qualität und Relevanz gezeigt: Marken stehen demnach vor der Herausforderung, ästhetische, zielgruppenrelevante Inhalte, die an die Eigenheiten Instagrams als Plattform angepasst sind, zu veröffentlichen und auf Augenhöhe mit den Nutzern zu kommunizieren, ohne sich selbst als Marke zu verlieren. Ferner führte die Expertenbefragung zu der Erkenntnis, dass Instagram sowohl als Community als auch als Marketing-Tool weiterhin an Bedeutung gewinnen wird, vor allem im deutschen Raum und in der Beauty-Branche.
The following contribution deals with the experimental investigation and theoretical evaluation of fatigue crack growth under isothermal and non-isothermal conditions at the nickel alloy 617. The microstructure and mechanical properties of alloy 617 are influenced significantly by the thermal heat treatment and the following thermal exposure in service. Hence, a solution annealed and a long-time service exposed material condition is studied. The crack growth measurement is carried out by using an alternate current potential drop system, which is integrated into a thermomechanical fatigue (TMF) test facility. The measured fatigue crack growth rates results in a function of material condition, temperature and load waveform. Furthermore, the results of the non-isothermal tests depend on the phase between thermal and mechanical load (in-phase, out-of-phase). A fracture mechanic based, time dependent model is upgraded by an approach to consider environmental effects, where almost all model parameters represent directly measureable values. A consistent description of all results and a good correlation with the experimental data can be achieved.
Unternehmen müssen aufgrund hohen Wettbewerbsdrucks ihre Produktivität stetig steigern. Ein Bereich, welcher sich deren permanenter Steigerung annimmt, ist das Industrial Engineering (IE). Gerade im Zuge der Digitalisierung und Vernetzung der Unternehmensprozesse beleuchtet der folgende Beitrag, wie sich Industrie 4.0 auf das IE auswirkt. Der Ansatz ist ein Industrial Engineering 4.0 zu gestalten, das die Fortschritte von Industrie 4.0 und der Digitalen Fabrik miteinander vereint.
6LoWPAN (IPv6 over Low Power Wireless Personal Area Networks) is gaining more and more attraction for the seamless connectivity of embedded devices for the Internet of Things (IoT). Whereas the lower layers (IEEE802.15.4 and 6LoWPAN) are already well defined and consolidated with regard to frame formats, header compression, routing protocols and commissioning procedures, there is still an abundant choice of possibilities on the application layer. Currently, various groups are working towards standardization of the application layer, i.e. the ETSI Technical Committee on M2M, the IP for Smart Objects (IPSO) Alliance, Lightweight M2M (LWM2M) protocol of the Open Mobile Alliance (OMA), and OneM2M. This multitude of approaches leaves the system developer with the agony of choice. This paper selects, presents and explains one of the promising solutions, discusses its strengths and weaknesses, and demonstrates its implementation.
In online analytical processing (OLAP), filtering elements of a given dimensional attribute according to the value of a measure attribute is an essential operation, for example in top-k evaluation. Such filters can involve extremely large amounts of data to be processed, in particular when the filter condition includes “quantification” such as ANY or ALL, where large slices of an OLAP cube have to be computed and inspected. Due to the sparsity of OLAP cubes, the slices serving as input to the filter are usually sparse as well, presenting a challenge for GPU approaches which need to work with a limited amount of memory for holding intermediate results. Our CUDA solution involves a hashing scheme specifically designed for frequent and parallel updates, including several optimizations exploiting architectural features of Nvidia’s Fermi and Kepler GPUs.
Verlage, die ihr Kernverbreitungsgebiet in lokalen oder regionalen Märkten haben, sind bereits seit Jahrzehnten in diesen Märkten im Werbe- und Nutzermarkt verankert. Beim Aufbau digitaler Geschäftsfelder können die bestehenden Kundenbeziehungen und Erfahrungen dazu benutzt werden, neue Dienste aufzubauen, die die Entwicklung zu mobilen Anwendungen, mit sozialem und lokalem Bezug für Anwendungen (z. B. Apps) mit echtem Informations- oder Gebrauchsmehrwert nutzen.
Führung braucht Klarheit
(2015)
Klarheit ist das grundlegende Prinzip für Führungserfolg und ist für die eigene Weiterentwicklung als Führungskraft von zentraler Bedeutung. Dazu gehören Klarheit über die eigene Person, Klarheit über die Führungsrolle, Klarheit über die Führungsziele oder auch die Klarheit über die Wertvorstellungen und Klarheit in der Führungskommunikation. Das Buch hilft Führungskräften, sich im Rahmen eines Selbstcoachings die notwendige Klarheit zu verschaffen. Checklisten und Praxisbeispiele ermöglichen den einfachen Transfer in den praktischen Führungsalltag.
Highlights
Konkrete Anleitung zum Selbstcoaching
Rasche Wirksamkeit durch Fokussierung auf „Klarheit“
Mit Selbstchecks und Fallstudien
Facebook - "App Zentrum"
(2015)
Wireless sensor networks have recently found their way into a wide range of applications among which environmental monitoring system has attracted increasing interests of researchers. Such monitoring applications, in general, don way into a wide range of applications among which environmental monitoring system has attracted increasing interests of researc latency requirements regarding to the energy efficiency. Also a challenge of this application is the network topology as the application should be able to be deployed in very large scale. Nevertheless low power consumption of the devices making up the network must be on focus in order to maximize the lifetime of the whole system. These devices are usually battery-powered and spend most of their energy budget on radio transceiver module. A so-called Wake-On-Radio (WoR) technology can be used to achieve a reasonable balance among power consumption, range, complexity and response time. In this paper, some designs for integration of WOR into IEEE 802.1.5.4 are to be discussed, providing an overview of trade-offs in energy consumption while deploying the WoR schemes in a monitoring system.
Extended Performance Measurements of Scalable 6LoWPAN Networks in an Automated Physical Testbed
(2015)
IPv6 over Low power Wireless Personal Area Networks, also known as 6LoWPAN, is becoming more and more a de facto standard for such communications for the Internet of Things, be it in the field of home and building automation, of industrial and process automation, or of smart metering and environmental monitoring. For all of these applications, scalability is a major precondition, as the complexity of the networks continuously increase. To maintain this growing amount of connected nodes a various 6LoWPAN implementations are available. One of the mentioned was developed by the authors' team and was tested on an Automated Physical Testbed for Wireless Systems at the Laboratory Embedded Systems and Communication Electronics of Offenburg University of Applied Sciences, which allows the flexible setup and full control of arbitrary topologies. It also supports time-varying topologies and thus helps to measure performance of the RPL implementation. The results of the measurements prove an excellent stability and a very good short and long-term performance also under dynamic conditions. In all measurements, there is an advantage of minimum 10% with regard to the average times, like global repair time; but the advantage with reagr to average values can reach up to 30%. Moreover, it can be proven that the performance predictions from other papers are consistent with the executed real-life implementations.
EuGH "Videoüberwachung"
(2015)
Das Thema Ethnomarketing gewinnt mit der steigenden Anzahl an Mitbürgern mit Migrationshintergrund an Wert. Bestimmte Marketingmaßnahmen für bestimmte Zielgruppen. Diese wissenschaftliche Arbeit befasst sich mit diesem Thema und die Widerspiegelung (Medienintegration) dieser in den Medien. Anhand von verschiedenen Beispielen wird das Thema überschaubar und verständlich beleuchtet.
It is the purpose of this paper to address ethical issues concerning the development and application of Assistive Technology at Workplaces (ATW). We shall give a concrete technical concept how such technology might be constructed and propose eight technical functions it should adopt in order to serve its purpose. Then, we discuss the normative questions why one should use ATW, and by what means. We argue that ATW is good to the extent that it ensures social inclusion and consider four normative domains in which its worth might consists in. In addition, we insist that ATW must satisfy two requirements of good workplaces, which we specify as (a) an exploitation restraint and (b) a duty of care.
Diese Arbeit beschäftigt sich mit den verschiedenen Technologien, welche in verteilten Systemen zur Kommunikation dienen können. Kernpunkt der Arbeit ist es, eine Schnittstelle zu schaffen, in der eine extrem hohe Anzahl einzelner Anwendungen untereinander und mit einer zentralen Simulationsumgebung weitestgehend automatisch - kommunizieren können. Dabei ist auch ein wesentlicher Punkt die Frage wie Daten ausgetauscht werden können. Betrachtet man zunächst das System an sich, so wird es deutlich, dass speziell für die Entwicklung des Gesamtsystems, die Stabilität, Leistungsfähigkeit und Zuverlässigkeit des Interfaces von enormer Wichtigkeit ist.
Diese Bachelor-Thesis beschreibt die Realisierung einer Webanwendung für Schüler und Studierende, welche interaktiv demonstriert, wie das Binärsystem funktioniert. Die Anwender sollen verstehen, wie ein Computer die Vielzahl an Daten mit lediglich zwei Zuständen, nämlich 1 und 0, verarbeitet. Dabei wird interaktiv gezeigt, wie der Algorithmus zur Umwandlung von Dezimalzahlen ins Binärsystem abläuft und wie man mit Binärzahlen rechnen kann. Außerdem gibt es sehr interessante Knobelaufgaben. Dabei wird versucht, dem User auf spielerische Art und Weise, zum Beispiel durch Spiele und Aktivitäten, die Denkweise eines Informatikers näher zu bringen. Das Ziel soll sein, dass sich das ursprüngliche Bild, welches Schüler von der Informatik haben, positiv verändert. Hierzu wird ein passendes didaktisches Konzept entwickelt, welches didaktische Modelle, Lehr-/Lernbedingungen und Lernziele der Webanwendung abbildet. Zunächst gibt es eine Einführung in die Thematik und der Stand der Technik wird erläutert, d.h. was bereits in diesem Umfeld existiert. Danach wird besonders auf die Realisierung der Applikation eingegangen. Hier werden Techniken und Werkzeuge für einen Lösungsansatz erklärt. Zuletzt wird das Thema zusammengefasst und evaluiert um einen anschließenden Ausblick geben zu können.
Im Rahmen dieser Arbeit wurde ein Telepräsenzsystem entwickelt, bei dem ein Teleroboter mit beweglicher Kamera zum Einsatz kommt, der seine Ausrichtung über ein Head-mounted Display synchronisiert. Der Anwender des Systems sieht auf dem Display das Abbild der Umgebung des Teleroboters. Jede Kopfbewegung des Anwenders wird in Echtzeit auf die Kamerabewegung umgesetzt. Der Anwender kann sozusagen seinen Sehsinn temporär auf den Roboter auslagern, der ihn in einer entfernten Umgebung repräsentiert.
This paper presents a practice and science orientated education approach for freshman students of interdisciplinary bachelor engineering degree programs. This approach is meant to enhance the motivation and success of freshman students during their whole study. The education approach is called Fit4PracSis (Fit for Practice and Sciences) It was started to develop, set up and establish an education approach, which is building a relationship to students' future profession and to scientific working during the introductory study phase. The freshman students will be trained early in important skills, which are necessary for achieving the final degree successfully and handling of future business and research activities.
The current methods used to assess the energy performance of ventilation devices do not consider all the aspects necessary for a comprehensive evaluation of decentralised ventilation concepts and can only be partially adapted to their needs. In order to improve the energy evaluation and to ensure the comparability of different systems, a calorimetric method was developed and implemented in test facilities for the evaluation of two decentralised devices: one equipped with a recuperative counter flow heat exchanger and one with a regenerative heat exchanger. This method, based on direct measurements of the heating load in an insulated test room, includes the effect of the electrical consumption of the fans on the energy performance of the ventilation devices. The calorimetric evaluation method was extended to a seasonal evaluation on the basis of a heating-degree-day method implemented for a warm, a cool and a moderate location in Europe: Athens, Strasbourg and Copenhagen. All the results are above 50% efficiency for both devices, even in Athens where the use of heat recovery ventilation is not usual.
The instability of ultra-thin films of an electrolyte bordering a dielectric gas in an external tangential electric field is scrutinized. The solid wall is assumed to be either a conducting or charged dielectric surface. The problem has a steady one-dimensional solution. The theoretical results for a plug-like velocity profile are successfully compared with available experimental data. The linear stability of the steady-state flow is investigated analytically and numerically. Asymptotic long-wave expansion has a triple-zero singularity for a dielectric wall and a quadruple-zero singularity for a conducting wall, and four (for a conducting wall) or three (for a charged dielectric wall) different eigenfunctions. For infinitely small wave numbers, these eigenfunctions have a clear physical meaning: perturbations of the film thickness, of the surface charge, of the bulk conductivity, and of the bulk charge. The numerical analysis provides an important result: the appearance of a strong short-wave instability. At increasing Debye numbers, the short-wave instability region becomes isolated and eventually disappears. For infinitely large Weber numbers, the long-wave instability disappears, while the short-wave instability persists. The linear stability analysis is complemented by a nonlinear direct numerical simulation. The perturbations evolve into coherent structures; for a relatively small external electric field, these are large-amplitude surface solitary pulses, while for a sufficiently strong electric field, these are short-wave inner coherent structures, which do not disturb the surface.
Cardiac resynchronization therapy (CRT) is an established biventricular pacing therapy in heart failure patients with left bundle branch block and reduced left ventricular ejection fraction, but not all patients improved clinically as CRT responder. Purpose of the study was to evaluate electrical left atrial conduction delay (LACD) with focused transesophageal electrocardiography in CRT responder and CRT non-responder.
Methods: Twenty heart failure patients (age 66.6±8.2 years; 2 females, 18 males) with New York Heart Association functional class 3.0±0.3 and 174.2±40.2ms QRS duration were analysed using posterior left atrial transesophageal electrocardiography with hemispherical electrodes. Electrical LACD was measured between onset and offset of transesophageal left atrial signal before implantation of CRT devices.
Results: Electrical LACD could be evaluated by bipolar transesophageal left atrial electrocardiography using TO Osypka electrode in all heart failure patients with negative correlation between 54.7±18.1ms LACD and 24.9±6.4% left ventricular ejection fraction (r=-0.65, P=0.002). There were 16 CRT responders with reduction of New York Heart Association functional class from 3.0±0.29 to 2.1±0.2 (r=0.522, P=0.038) during 9.41±10.96 month biventricular pacing and negative correlation between 49.6±14.2ms LACD and 26.0±6.2% left ventricular ejection fraction (r=-0.533, P=0.034). There were 4 CRT non-responders with no reduction of New York Heart Association functional class from 3.0±0.4 to 2.8±0.5 (r=0.816, P=0.184) during with 13.88±16.39 month biventricular pacing and no correlation between 75.25±19.17ms LACD and 20.75±6.4% left ventricular ejection fraction (r=-0.831, P=0.169).
Conclusions: Focused transesophageal left atrial electrocardiography can be utilized to analyse electrical LACD in heart failure patients. LACD correlated negative with left ventricular ejection fraction in CRT responders. LACD may be a useful parameter to evaluate electrical left atrial desynchronization in heart failure patients.
Cardiac resynchronization therapy (CRT) is an established class I level A biventricular pacing therapy in chronic heart failure patients with left bundle branch block and reduced left ventricular ejection fraction, but not all patients improved clinically. Purpose of the study was to evaluate electrical interatrial conduction delay (IACD) to interventricular conduction delay (IVCD) ratio with focused transesophageal left atrial and left ventricular electrocardiography.
Methods: Thirty eight chronic heart failure patients (age 63.4±10.2 years; 3 females, 35 males) with New York Heart Association (NYHA) functional class 3.0±0.2 and 171.71±36.17ms QRS duration were analysed using posterior left atrial and left ventricular transesophageal electrocardiography with hemispherical electrodes before CRT. Electrical IACD was measured between onset of P-wave in the surface ECG and onset of left atrial signal. Electrical IVCD was measured between onset of QRS complex in the surface ECG and onset of left ventricular signal.
Results: Electrical IACD and IVCD could be evaluated by transesophageal left atrial and left ventricular electrocardiography in all heart failure patients with correlation to 1.18±0.92 IACD-IVCD-ratio (r=-0.57, P<0.001; r=0.66, P<0.001). There were 32 CRT responder with reduction of NYHA class from 3.0±0.22 to 1.97±0.31 (P<0.001) during 16.5±18.9 month CRT with 75.19±33.49ms IACD, 78.91±24.73ms IVCD, 1.04±0.66 IACD-IVCD-ratio and correlation between IACD and IACDIVCD- ratio (r=0.84, P<0.001). There were 6 CRT nonresponder with no reduction of NYHA class from 3.0±0.3 to 2.9±0.5 during 14.3±13.7 month biventricular pacing, 50.0±28.26ms IVCD (P=0.014), 1.92±1.65 IACD-IVCD-ratio (P=0,029) and correlation between 67.0±24.9ms IACD and IACD-IVCD-ratio (r=0.85, P=0.031).
Conclusions: Focused transesophageal left atrial and left ventricular electrocardiography can be utilized to analyse electrical IACD and IVCD in heart failure patients. IACDIVDC- ratio may be a useful parameter to evaluate electrical left cardiac desynchronization in heart failure patients.
Since 2003, most European countries established heat health warning systems to alert the population to heat load. Heat health warning systems are based on predicted meteorological conditions outdoors. But the majority of the European population spends a substantial amount of time indoors, and indoor thermal conditions can differ substantially from outdoor conditions. The German Meteorological Service (Deutscher Wetterdienst, DWD) extended the existing heat health warning system (HHWS) with a thermal building simulation model to consider heat load indoors. In this study, the thermal building simulation model is used to simulate a standardized building representing a modern nursing home, because elderly and sick people are most sensitive to heat stress. Different types of natural ventilation were simulated. Based on current and future test reference years, changes in the future heat load indoors were analyzed. Results show differences between the various ventilation options and the possibility to minimize the thermal heat stress during summer by using an appropriate ventilation method. Nighttime ventilation for indoor thermal comfort is most important. A fully opened window at nighttime and the 2-h ventilation in the morning and evening are more sufficient to avoid heat stress than a tilted window at nighttime and the 1-h ventilation in the morning and the evening. Especially the ventilation in the morning seems to be effective to keep the heat load indoors low. Comparing the results for the current and the future test reference years, an increase of heat stress on all ventilation types can be recognized.
Lithium-oxygen cells with organic electrolyte suffer high overpotentials during charge, indicating asymmetric charge/discharge reaction mechanisms. We present a multi-physics dynamic modeling and simulation study of the Li/O2 cell cycling behavior. We present three different multi-step mechanisms of the 2 Li + O2 ⇄ Li2O2 cell reaction, (A) a reversible 5-step mechanism, (B) a partially irreversible 6-step mechanism, and (C) a partially irreversible 8-step mechanism that includes reactions of a redox mediator. Model predictions are compared to experimental galvanostatic cycling data of Swagelok cells without and with 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) as redox mediator. All mechanisms are able to predict the discharge behavior in good agreement to the experimental results. The experimentally observed high charge overpotentials as well as their reduction by using a redox mediator can be qualitatively reproduced with the irreversible reaction mechanisms. However, the particular shape of the experimental charge curve with continuously increasing charge overpotential cannot be reproduced with the present mechanisms.
In this paper, the correlation of the cyclic J-integral, ΔJ, and the cyclic crack-tip opening displacement, ΔCTOD, is studied in the presence of crack closure to assess the question if ΔJ describes the crack-tip opening displacement in this case. To this end, a method is developed to evaluate ΔJ numerically within finite-element calculations. The method is validated for an elastic–plastic material that exhibits Masing behavior. Different strain ranges and strain ratios are considered under fully plastic cyclic conditions including crack closure. It is shown that the cyclic J-integral is the parameter to determine the cyclic crack-tip opening displacement even in cases where crack closure is present.
Distribution of esophageal interventricular conduction delays in CRT patients and healthy subjects
(2015)
Die digitalen Medien nehmen in der heutigen Zeit, besonders bei Kindern und Jugendlichen, einen hohen Stellenwert ein und beeinflussen das Leben der Heranwachsenden. Diese Arbeit bezieht sich auf das Thema „Digitale Medien im Unterricht – Herausforderung, Methode, Perspektive“, welches sich mit der Zusammenarbeit digitaler Medien im Unterricht, die dabei entstehenden
Herausforderung für einen gezielten Einsatz und der Perspektive für das Einbeziehen digitaler Medien in Schulen richtet.
Auch und gerade im Gesundheitswesen müssen Daten zwischen diversen Stellen ausgetauscht werden. Dies geschieht in der Praxis regelmäßig etwa zur Abrechnung von Versicherungsleistungen, bei Überweisungen von Patienten und im Abrechnungswesen der Ärzteschaft. Aber auch die Übernahme einer Arztpraxis ist ein Problemfall. Schon die Erhebung von Gesundheitsdaten bedarf aufgrund des datenschutzrechtlichen Verbots mit Erlaubnisvorbehalt (§ 4 BDSG) einer Rechtsgrundlage. Umso mehr darf die Weitergabe von Patientendaten als besonderen personenbezogenen Daten i.S.d. § 3 Abs. 9 BDSG nur erfolgen, wenn sie durch Gesetz oder durch die Einwilligung der betroffenen Person gestattet wurde. Eine Einwilligung durch Unterzeichnung einer klauselmäßige Schweigepflichtentbindung ist möglich, unterliegt aber bestimmten formalen und inhaltlichen Anforderungen.
Video game developers continuously increase the degree of details and realism in games to create more human-like characters. But increasing the human-likeness becomes a problem in regard to the Uncanny Valley phenomenon that predicts negative feelings of people towards artificial entities. We developed an avatar creation system to examine preferences towards parametrized faces and explore in regard to the Uncanny Valley phenomenon how people design faces that they like or reject. Based on the 3D model of the Caucasian average face, 420 participants generate 1341 faces of positively and negatively associated concepts of both gender. The results show that some characteristics associated with the Uncanny Valley are used to create villains or repulsive faces. Heroic faces get attractive features but are rarely and little stylized. A voluntarily designed face is very similar to the heroine. This indicates that there is a tendency of users to design feminine and attractive but still credible faces.
Design approaches for the gamification of production environments: a study focusing on acceptance
(2015)
Gamification is an ever more popular method to increase motivation and user experience in real-world settings. It is widely used in the areas of marketing, health and education. However, in production environments, it is a new concept. To be accepted in the industrial domain, it has to be seamlessly integrated in the regular work processes.
In this work we make the following contributions to the field of gamification in production: (1) we analyze the state of the art and introduce domain-specific requirements; (2) we present two implementations gamifying production based on alternative design approaches; (3) these are evaluated in a sheltered work organization. The comparative study focuses acceptance, motivation and perceived happiness.
The results reveal that a pyramid design showing each work process as a step on the way towards a cup at the top is strongly preferred to a more abstract approach where the processes are represented by a single circle and two bars.
DEM–FEA estimation of pores arrangement effect on the compressive Young’s modulus for Mg foams
(2015)
This work reports the study of the effect of the pore arrangement on the compressive behavior of Mg foams with regular pore size and porosities ranging from 25% to 45%. Pore arrangements were modeled using Finite Element Analysis (FEA), with random and ordered models, and compared to the estimations obtained for a previous work. The coordinates of the random pore arrangements were firstly generated using Discrete Element Method (DEM), and used in a second stage for modeling the pores by FEA. Estimations were also compared to the experimental results for Mg foams obtained by means of powder metallurgy. Results show important drops in the Young’s moduli as the porosity increases for both, experimental results and FEA estimations. Estimations obtained using ordered pore arrangements presented significant differences when compared to the estimations acquired from models with random arrangements. The randomly arranged models represent more accurately the real topologies of the experimental metallic foams. The Young’s moduli estimated using these models were in excellent agreement with the experiments, whilst the estimations obtained using ordered models presented relative errors significantly higher. The importance of the use of more realistic FEA models for improving the predicting ability of this method was probed, for the study of the mechanical properties of metallic foams.
Demand Side Management for Thermally Activated Building Systems based on Multiple Linear Regression
(2015)
In this work we describe the implementation details of a protocol suite for a secure and reliable over-the-air reprogramming of wireless restricted devices. Although, recently forward error correction codes aiming at a robust transmission over a noisy wireless medium have extensively been discussed and evaluated, we believe that the clear value of the contribution at hand is to share our experience when it comes to a meaningful combination and implementation of various multihop (broadcast) transmission protocols and custom-fit security building blocks: For a robust and reliable data transmission we make use of fountain codes a.k.a. rateless erasure codes and show how to combine such schemes with an underlying medium access control protocol, namely a distributed low duty cycle medium access control (DLDC-MAC). To handle the well known problem of packet pollution of forward-error-correction approaches where an attacker bogusly modifies or infiltrates some minor number of encoded packets and thus pollutes the whole data stream at the receiver side, we apply homomorphic message authentication codes (HomMAC). We discuss implementation details and the pros and cons of the two currently available HomMAC candidates for our setting. Both require as the core cryptographic primitive a symmetric block cipher for which, as we will argue later, we have opted for the PRESENT, PRIDE and PRINCE (exchangeable) ciphers in our implementation.
The objective of this thesis is the conceptual design of a battery management system for the first prototype of the UWC (University of the Western Cape) Modular Battery System. The battery system is a lithium-ion battery that aims to be used in renewable energy systems and for niche electric vehicles such as golf carts.
The concept that is introduced in this thesis comprises the parameter monitoring, the safety management and has its main focus on an accurate state of charge estimation.
Another battery system that was already implemented is used as base for the parameter monitoring and the safety management for the new battery management system. In contrast to that, the concept for the state of charge estimation must be developed completely.
Different methods for the state of charge estimation which are based on the measured voltage, current and temperature are discussed, evaluated and the chosen method is conceived in this thesis. The method used for the state of charge estimation is different for the time when the battery is active than when it is inactive. During charge and discharge Coulomb counting is used and when the cell is inactive voltage versus state of charge lookup tables are used to update the estimation.
To have an accurate estimation when the cell is inactive only for a short time, a model of the voltage relaxation is used to predict the voltage when the cells are in equilibrium. This allows the algorithm to reset the state of charge that is estimated by Coulomb counting – which tends to have a growing error over time – frequently.
To evaluate the accuracy of the voltage prediction, cell tests were executed where the voltage relaxation was sampled. The recursive least square method to predict the end voltage was tested with a MATLAB programme. With the help of voltage versus state of charge lookup tables it was possible to determine the state of charge accuracy with the accuracy of the voltage prediction.
With projectors and depth cameras getting cheaper, assistive systems in industrial manufacturing are becoming increasingly ubiquitous. As these systems are able to continuously provide feedback using in-situ projection, they are perfectly suited for supporting impaired workers in assembling products. However, so far little research has been conducted to understand the effects of projected instructions on impaired workers. In this paper, we identify common visualizations used by assistive systems for impaired workers and introduce a simple contour visualization. Through a user study with 64 impaired participants we compare the different visualizations to a control group using no visual feedback in a real world assembly scenario, i.e. assembling a clamp. Furthermore, we introduce a simplified version of the NASA-TLX questionnaire designed for impaired participants. The results reveal that the contour visualization is significantly better in perceived mental load and perceived performance of the participants. Further, participants made fewer errors and were able to assemble the clamp faster using the contour visualization compared to a video visualization, a pictorial visualization and a control group using no visual feedback.
Seven cell design concepts for aqueous (alkaline) lithium–oxygen batteries are investigated using a multi-physics continuum model for predicting cell behavior and performance in terms of the specific energy and specific power. Two different silver-based cathode designs (a gas diffusion electrode and a flooded cathode) and three different separator designs (a porous separator, a stirred separator chamber, and a redox-flow separator) are compared. Cathode and separator thicknesses are varied over a wide range (50 μm–20 mm) in order to identify optimum configurations. All designs show a considerable capacity-rate effect due to spatiotemporally inhomogeneous precipitation of solid discharge product LiOH·H2O. In addition, a cell design with flooded cathode and redox-flow separator including oxygen uptake within the external tank is suggested. For this design, the model predicts specific power up to 33 W/kg and specific energy up to 570 Wh/kg (gravimetric values of discharged cell including all cell components and catholyte except housing and piping).
Recent advances in motion recognition allow the development of Context-Aware Assistive Systems (CAAS) for industrial workplaces that go far beyond the state of the art: they can capture a user's movement in real-time and provide adequate feedback. Thus, CAAS can address important questions, like Which part is assembled next? Where do I fasten it? Did an error occur? Did I process the part in time? These new CAAS can also make use of projectors to display the feedback within the corresponding area on the workspace (in-situ). Furthermore, the real-time analysis of work processes allows the implementation of motivating elements (gamification) into the repetitive work routines that are common in manual production. In this chapter, the authors first describe the relevant backgrounds from industry, computer science, and psychology. They then briefly introduce a precedent implementation of CAAS and its inherent problems. The authors then provide a generic model of CAAS and finally present a revised and improved implementation.