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Grundzüge der Strömungslehre
(2015)
Dieses erfolgreiche, didaktisch ausgereifte Lehrbuch wurde im Bereich der Übungsaufgaben erweitert. Leserhinweise wurden eingearbeitet. Es zeichnet sich durch eine prägnant kurze, mathematisch verständliche und anwendbare Einführung in die Grundlagen aus und hilft dem Leser, sein Verständnis durch Übungen mit kompletten Lösungen zu vertiefen.
Planung und Umsetzung einer Medieninstallation mit dem Schwerpunkt: Steuerung über DMX und RS232
(2015)
Die vorliegende Arbeit stellt zunächst das Konzept und die Idee der Zeitmaschine als Installation vor. Anschließend werden die eingesetzte Technik und das verwendete Protokoll erklärt. Daraufhin nennt die Autorin die einzelnen Bauelemente und Geräte, erklärt wie diese für die Zeitmaschine zum Einsatz gebracht werden und stellt die technische Planung vor. Abschließend beschäftigt sich die Ausarbeitung mit der Software und dem Programmcode zur Steuerung der einzelnen Elemente.
Energietechnik
(2015)
Kurz und prägant werden die Energieumwandlungsprozesse dargestellt. Die Schwerpunkte reichen von der kompletten Beschreibung der nachhaltigen, erneuerbaren Energietechniken, über Gas- und Dampfturbinen-Kraftwerke sowie Kraft-Wärme-Kälte-Kopplungsanlagen bis hin zur Energieverteilung und zum Kyoto-Protokoll. Zu allen Kapiteln gibt es Aufgaben mit vollständigen Lösungen im Anhang. In der aktuellen Auflage wurden in den Kapiteln 3 und 15 die Zahlenwerte aktualisiert. Kapitel 9 wurde entsprechend der neuen Anbieterstruktur überarbeitet und Kapitel 10 um die Adsorptionstechniken ergänzt. Die Kapitel 17-20 wurden vollständig überarbeitet und stellen den aktuellen Stand der globalen politischen Aspekte dar.
The overview of public key infrastructure based security approaches for vehicular communications
(2015)
Modern transport infrastructure becomes a full member of globally connected network. Leading vehicle manufacturers have already triggered development process, output of which will open a new horizon of possibilities for consumers and developers by providing a new communication entity - a car, thus enabling Car2X communications. Nevertheless some of available systems already provide certain possibilities for vehicles to communicate, most of them are considered not sufficiently secured. During last 15 years a number of big research projects funded by European Union and USA governments were started and concluded after which a set of standards were published prescribing a common architecture for Car2X and vehicles onboard communications. This work concentrates on combining inner and outer vehicular communications together with a use of Public Key Infrastructure (PKI).
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.
Umsatzsteuer
(2015)
Inventar und Bilanz
(2015)
Warenverkehr
(2015)
Anschaffungskosten
(2015)
In many scientific studies lens experiments are part of the curriculum. The conducted experiments are meant to give the students a basic understanding for the laws of optics and its applications. Most of the experiments need special hardware like e.g. an optical bench, light sources, apertures and different lens types. Therefore it is not possible for the students to conduct any of the experiments outside of the university’s laboratory. Simple optical software simulators enabling the students to virtually perform lens experiments already exist, but are mostly desktop or web browser based.
Augmented Reality (AR) is a special case of mediated and mixed reality concepts, where computers are used to add, subtract or modify one’s perception of reality. As a result of the success and widespread availability of handheld mobile devices, like e.g. tablet computers and smartphones, mobile augmented reality applications are easy to use. Augmented reality can be easily used to visualize a simulated optical bench. The students can interactively modify properties like e.g. lens type, lens curvature, lens diameter, lens refractive index and the positions of the instruments in space. Light rays can be visualized and promote an additional understanding of the laws of optics. An AR application like this is ideally suited to prepare the actual laboratory sessions and/or recap the teaching content.
The authors will present their experience with handheld augmented reality applications and their possibilities for light and optic experiments without the needs for specialized optical hardware.
The demand of wireless solutions in industrial applications increases since the early nineties. This trend is not only ongoing, it is further pushed by developments in the area of software stacks like the latest Bluetooth Low Energy Stack. It is also pushed by new chip-designs and powerful and highly integrated electronic hardware. The acceptance of wireless technologies as a possible solution for industrial applications, has overcome the entry barrier [1]. The first step to see wireless as standard for many industrial applications is almost accomplished. Nevertheless there is nearly none acceptance of wireless technology for Safety applications. One highly challenging and demanding requirement is still unsolved: The aspect safety and robustness. Those topics have been addressed in many cases but always in a similar manner. WirelessHART as an example addresses this topic with redundant so called multiple propagation paths and frequency hopping to handle with interferences and loss of network participants. So far the pure peer to peer link is rarely investigated and there are less safety solutions available. One product called LoRa™ can be seen as one possible solution to address this lack of safety within wireless links. This paper focuses on the safety performance evaluation of a modem-chip-design. The use of diverse and redundant wireless technologies like LoRa can lead to an increase acceptance of wireless in safety applications. Many measurements in real industrial application have been carried out to be able to benchmark the new chip in terms of the safety aspects. The content of this research results can help to raise the level of confidence in wireless. In this paper, the term “safety” is used for data transmission reliability.
Sicher funken mit 2,45 GHz
(2015)
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.
The automatic classification of the modulation format of a detected signal is the intermediate step between signal detection and demodulation. If neither the transmitted data nor other signal parameters such as the frequency offset, phase offset and timing information are known, then automatic modulation classification (AMC) is a challenging task in radio monitoring systems. The approach of clustering algorithms is a new trend in AMC for digital modulations. A novel algorithm called `highest constellation pattern matching' is introduced to identify quadrature amplitude modulation and phase shift keying signals. The obtained simulation and measurement results outperform the existing algorithms for AMC based on clustering. Finally, it is shown that the proposed algorithm works in a real monitoring environment.
Security in IT systems, particularly in embedded devices like Cyber Physical Systems (CPSs), has become an important matter of concern as it is the prerequisite for ensuring privacy and safety. Among a multitude of existing security measures, the Transport Layer Security (TLS) protocol family offers mature and standardized means for establishing secure communication channels over insecure transport media. In the context of classical IT infrastructure, its security with regard to protocol and implementation attacks has been subject to extensive research. As TLS protocols find their way into embedded environments, we consider the security and robustness of implementations of these protocols specifically in the light of the peculiarities of embedded systems. We present an approach for systematically checking the security and robustness of such implementations using fuzzing techniques and differential testing. In spite of its origin in testing TLS implementations we expect our approach to likewise be applicable to implementations of other cryptographic protocols with moderate efforts.
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.
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.
Die vorliegende Erfindung betrifft ein Verfahren zum Pulverlackieren eines Glasgegenstandes, umfassend die Schritte des Ausbildens einer polaren Beschichtung auf dem Glasgegenstand, umfassend den Teilschritt des Aufbringens einer Beschichtungszusammensetzung auf den Glasgegenstand, wobei die Beschichtungszusammensetzung ein Organosiloxan, das mindestens zwei Si-O-Bindungen aufweist, Wasser, ein organisches Lösemittel und ein pH-regulierendes Mittel enthält, mit der Maßgabe, dass die Beschichtungszusammensetzung keinen elektrisch leitfähigen Zusatz enthält, sowie die Schritte des Aufbringens eines Pulverlacks auf den derartig beschichteten Glasgegenstand und des Erwärmens des Pulverlacks.
Monitors are in the center of media productions and hold an important function as the main visual interface. Tablets and smartphones are becoming more and more important work tools in the media industry. As an extension to our lecture contents an intensive discussion of different display technologies and its applications is taking place now. The established LCD (Liquid Crystal Display) technology and the promising OLED (Organic Light Emitting Diode) technology are in the focus.
The classic LCD is currently the most important display technology. The paper will present how the students should develop sense for display technologies besides the theoretical scientific basics. The workshop focuses increasingly on the technical aspects of the display technology and has the goal of deepening the students understanding of the functionality by building simple Liquid Crystal Displays by themselves.
The authors will present their experience in the field of display technologies. A mixture of theoretical and practical lectures has the goal of a deeper understanding in the field of digital color representation and display technologies. The design and development of a suitable learning environment with the required infrastructure is crucial. The main focus of this paper is on the hands-on optics workshop “Liquid Crystal Display in the do-it-yourself”.
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.
Cardiac resynchronization therapy (CRT) is an established therapy for heart failure patients and improves quality of life in patients with sinus rhythm, reduced left ventricular ejection fraction (LVEF), left bundle branch block and wide QRS duration. Since approximately sixty percent of heart failure patients have a normal QRS duration they do not benefit or respond to the CRT. Cardiac contractility modulation (CCM) releases nonexcitatoy impulses during the absolute refractory period in order to enhance the strength of the left ventricular contraction. The aim of the investigation was to evaluate differences in cardiac index between optimized and nonoptimized CRT and CCM devices versus standard values. Impedance cardiography, a noninvasive method was used to measure cardiac index (CI), a useful parameter which describes the blood volume during one minutes heart pumps related to the body surface. CRT patients indicate an increase of 39.74 percent and CCM patients an improvement of 21.89 percent more cardiac index with an optimized device.
Im Projekt bwLehrpool wurde ein verteiltes System für die flexible Nutzung von Rechnerpools durch Desktop-Virtualisierung entwickelt. Auf Basis eines zentral gebooteten Linux- Grundsystems können beliebige virtualisierbare Betriebssysteme für Lehrund Prüfungszwecke zentral bereitgestellt und lokal auf den Maschinen aus-gewählt werden. Die verschiedenen Ar- beitsumgebungen müssen nicht mehr auf den PCs installiert werden und erlauben so eine multifunktionale Nutzung von PCs und Räumen für vielfältige Lehrund Lernszenarien sowie für elektronische Prüfungen. bwLehrpool abstrahiert von der PC-Hardware vor Ort und ermöglicht den Dozenten die eigene Gestaltung und Verwaltung ihrer Softwareumgebungen als Self-Service. Darüber hinaus fördert bwLehrpool den hochschulübergreifenden Austausch von Kursumgebungen.
Bluetooth Low Energy extends the Bluetooth standard in version 4.0 for ultra-low energy applications through the extensive usage of low-power sleeping periods, which inherently difficult in frequency hopping technologies. This paper gives an introduction into the specifics of the Bluetooth Low Energy protocol, shows a sample implementation, where an embedded device is controlled by an Android smart phone, and shows the results of timing and current consumption measurements.
Transcatheter aortic valve implantation is a therapy for patients with reduced left ventricular ejection fraction and symptomatic aortic stenosis. The aim of the study was to compare the pre-and post- transcatheter aortic valve implantation procedures to determine the QRS and QT ventricular conduction times as a potential predictor of permanent pacemaker therapy requirement after transcatheter aortic valve implantation. QRS and QT ventricular conduction times were prolonged after transcatheter aortic valve implantation in heart failure patients with permanent dual chamber pacemaker therapy after transcatheter aortic valve implantation. QRS and QT ventricular conduction times may be useful parameters to evaluate the risk of post-procedural ventricular conduction block and permanent pacemaker therapy in transcatheter aortic valve implantation.
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.
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.
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.
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.
Poröse Massen oder Formkörper aus anorganischen polymeren und deren Herstellung (EP000002958875A1)
(2015)
An Extraction Method for 17α-Ethinylestradiol from Water using a new kind of monolithic Stir-bar
(2015)
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.
The main focus of this chapter is the theoretical and instrumental processes that underpin densitometric methods widely used in thin-layer chromatography (TLC). Densitometric methods include UV–vis, luminescence and fluorescence optical measurements as well as infrared and Raman spectroscopic measurements. The chapter is divided in two general parts: a theoretical part and a practical part. The systems for direct radioactivity measurements and the combination of TLC with mass spectrometry are also discussed. All these systems allow measuring an intensity distribution directly on a TLC plate. We call this “in situ detection” because no analyte is removed from the plate.
Die Vermittlung von Handlungs-und Prozesswissen in der industriellen Produktion erfordert neue Ansätze, insbesondere eine Flexibilisierung und Integration von Lernprozessen in reale Arbeitssituationen. Der vorliegende Beitrag beschreibt das Zwischenergebnis eines größeren Forschungsvorhabens im Bereich Mobile Learning mit kontextbezogenen mobilen Diensten im betrieblichen Umfeld. Er stellt Anforderungen, Lösungsansätze und einen Prototypen zur Realisie-rung von kontextbezogenen mobilen Diensten im Bereichder Unfallverhütung und Sicherheits-einweisungen in Fertigungsprozessen vor. Die zu unterstützenden kontextbezogenen Prozesse eines Industriepartners werden analysiert und unter Verwendung eines Domänenmodells, generi-scher Prozessmodelle und kontextbezogenen mobilen Anwendungen realisiert. Im Beitrag werden außerdem Lösungsansätze für plattformunabhängige mobile Applikationen, sowie die Integration von Persistenzmechanismen und Gerätefunktionen mittels hybrider Ansätze vorgestellt. Ergebnis der Arbeit ist ein erster Prototyp einer hybriden mobilen Applikation der im realen Betrieb syste-matisch getestet und weiterentwickelt wird.
Umgang mit Lebenskrisen
(2015)
The increasing number of transistors being clocked at high frequencies of modern microprocessors lead to an increasing power consumption, which calls for an active dynamic thermal management. In a research project a system environment has been developed, which includes thermal modeling of the microprocessor in the board system, a software environment to control the characteristics of the system’s timing behavior, and a modified Linux scheduler, which is enhanced with a prediction controller. Measurement results are shown for this development for a Freescale i.MX6Q quad-core microprocessor.
IFRS in 1 Stunde
(2015)
The application of leaky feeder (radiating) cables is a common solution for the implementation of reliable radio communication in huge industrial buildings, tunnels and mining environment. This paper explores the possibilities of leaky feeders for 1D and 2D localization in wireless systems based on time of flight chirp spread spectrum technologies. The main focus of this paper is to present and analyse the results of time of flight and received signal strength measurements with leaky feeders in indoor and outdoor conditions. The authors carried out experiments to compare ranging accuracy and radio coverage area for a point-like monopole antenna and for a leaky feeder acting as a distributed antenna. In all experiments RealTrac equipment based on nanoLOC radio standard was used. The estimation of the most probable path of a chirp signal going through a leaky feeder was calculated using the ray tracing approach. The typical non-line-of-sight errors profiles are presented. The results show the possibility to use radiating cables in real time location technologies based on time-of-flight method.
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.
Verfahren zur Bestimmung von Eigenschaften einer Rohrleitung, insbesondere der Position eines Abzweigs einer Abwasserrohrleitung, (a) bei dem ein Schallwellensendesignal (S, S') an einem vorgegebenen Einspeisepunkt in die Rohrleitung (1) eingespeist wird und sich in axialer Richtung der Rohrleitung (1) ausbreitet, (b) wobei das Frequenzspektrum des Schallwellensendesignals (S, S') eine Frequenzkomponente oder einen Spektralbereich aufweist, dessen maximale Frequenz kleiner ist als die untere Grenzfrequenz (fc) für die erste Obermode, (c) bei dem innerhalb der Rohrleitung (1) reflektierte Anteile (Sr1, Sr2, Sr3, S'r1, S'r2, S'r3) des Schallwellensendesignals (S, S') als Schallwellenempfangssignal (E, E') detektiert werden, und (d) bei dem die Rohrleitung (1) durch eine Auswertung des Schallwellenempfangssignal (E, E') in Bezug auf das Schallwellensendesignal (S, S') hinsichtlich des Vorhandenseins von Schallwellenreflexionen (Sr1, Sr2, Sr3, S'r1, S'r2, S'r3) verursachenden Reflexionsorten entlang der Rohrleitung (1) untersucht wird, (e) wobei mittels der Auswertung des Schallwellenempfangssignals (E, E') zumindest jeweils der Abstand (I) eines Reflexionsortes von dem Einspeisepunkt bestimmt wird.
In dieser Thesis wird im ersten Teil ein Überblick über das Internet der Dinge gegeben. Dabei geht es um den aktuellen Stand der Technik in diesem Bereich. Danach wird die Thematik Wearables aufgegriffen und bearbeitet. Der andere Teil der Arbeit ist die Entwicklung einer Wearable-Anwendung. Realisiert wird eine Gewichtsmessungseinheit an einer Handtasche. Diese gibt ihrem Nutzer Rückmeldungen über das Gewicht der Tasche und in wie weit dieses für das Körpergewicht des Anwenders im Rahmen eines gesunden Maßes ist.
Diese Arbeit befasst sich mit der Konzeption und Entwicklung einer SharePoint App, die einen Datenabgleich zwischen Zoho CRM und JIRA ermöglicht. Mittels dieser App ist es möglich, einen Supportfall, den der Support mittels Zoho CRM aufgenommen hat, bei Bedarf der Entwicklung zuzuweisen, indem in JIRA ein neues Ticket erstellt wird. Des Weiteren können durch die App Informationen, wie Firmen- und Kontaktdaten beiden Abteilungen zugänglich gemacht werden. Realisiert wird dies auf Basis von SharePoint, auf das alle beteiligten Mitarbeiter Zugriff haben. Zunächst wird für eine Lösung mit SharePoint dessen App-Modell analysiert und die möglichen Hosting-Varianten evaluiert. Die dabei getroffene Entscheidung für eine SharePoint gehostete App wird zudem begründet. Um die Bearbeitung eines Supportfalls innerhalb der App zu ermöglichen, wird ein Workflow entworfen, der neben dem Ablauf der Bearbeitung auch die Kommunikation mit den beteiligten Anwendungen festlegt. Die zu diesem Zweck notwendige persistente Speicherung der Daten in der App erfolgt dabei mithilfe von SharePoint Listen. Diese werden aufgrund eines ähnlichen Aufbaus als Tabellen dargestellt. Die detaillierte Darstellung einzelner Listenelemente dagegen erfolgt mithilfe von Dialog-Fenstern, die von SharePoint bereitgestellt werden. Dabei werden abhängig von dem Land aus dem die App aufgerufen wird, die Texte auf Deutsch oder auf Englisch angezeigt.
Demand Side Management for Thermally Activated Building Systems based on Multiple Linear Regression
(2015)
Photovoltaics Energy Prediction Under Complex Conditions for a Predictive Energy Management System
(2015)
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.
Autonomous humanoid robots require light weight, high torque and high speed actuators to be able to walk and run. For conventional gears with a fixed gear ratio the product of torque and velocity is constant. On the other hand desired motions require maximum torque and speed. In this paper it is shown that with a variable gear ratio it is possible to vary the relation between torque and velocity. This is achieved by introducing systems of rods and levers to move the joints of our humanoid robot ”Sweaty II”. On the basis of a variable gear ratio low speed and high torque can be achieved for those joint angles, which require this motion mode, whereas high speed and low torque can be realized for those joint angles, where it is favorable for the desired motion.
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. It can be observed that most of the available solutions are following an open source approach, which significantly leads to a fast development of technologies and of markets. Although the currently available implementations are in a pretty good shape, all of them come with some significant drawbacks. It was therefore decided to start the development of an own implementation, which takes the advantages from the existing solutions, but tries to avoid the drawbacks. This paper discussed the reasoning behind this decision, describes the implementation and its characteristics, as well as the testing results. The given implementation is available as open-source project under [15].
The transformation of the building energy sector to a highly efficient, clean, decentralised and intelligent system requires innovative technologies like microscale trigeneration and thermally activated building structures (TABS) to pave the way ahead. The combination of such technologies however presents a scientific and engineering challenge. Scientific challenge in terms of developing optimal thermo-electric load management strategies based on overall energy system analysis and an engineering challenge in terms of implementing these strategies through process planning and control. Initial literature research has pointed out the need for a multiperspective analysis in a real life laboratory environment. To this effect an investigation is proposed wherein an analytical model of a microscale trigeneration system integrated with TABS will be developed and compared with a real life test-rig corresponding to building management systems. Data from the experimental analysis will be used to develop control algorithms using model predictive control for achieving the thermal comfort of occupants in the most energy efficient and grid reactive manner. The scope of this work encompasses adsorption cooling based microscale trigeneration systems and their deployment in residential and light commercial buildings.
The energy system of the future will transform from the current centralised fossil based to a decentralised, clean, highly efficient, and intelligent network. This transformation will require innovative technologies and ideas like trigeneration and the crowd energy concept to pave the way ahead. Even though trigeneration systems are extremely energy efficient and can play a vital role in the energy system, turning around their deployment is hindered by various barriers. These barriers are theoretically analysed in a multiperspective approach and the role decentralised trigeneration systems can play in the crowd energy concept is highlighted. It is derived from an initial literature research that a multiperspective (technological, energy-economic, and user) analysis is necessary for realising the potential of trigeneration systems in a decentralised grid. And to experimentally quantify these issues we are setting up a microscale trigeneration lab at our institute and the motivation for this lab is also briefly introduced.
Distributed Flow Control and Intelligent Data Transfer in High Performance Computing Networks
(2015)
This document contains my master thesis report, including problem definition, requirements, problem analysis, review of current state of the art, proposed solution,
designed prototype, discussions and conclusion.
During this work we propose a collaborative solution to run different types of operations in a broker-less network without relying on a central orchestrator.
Based on our requirements, we define and analyze a number of scenarios. Then we design a solution to address those scenarios using a distributed workflow management approach. We explain how we break a complicated operation into simpler parts and how we manage it in a non-blocking and distributed way. Then we show how we asynchronously launch them on the network and how we collect and aggregate results. Later on we introduce our prototype which demonstrates the proposed design.
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.
Der Wochenmarkt im Internet - Exemplarische Konzeption einer Webpräsenz und prototypische Umsetzung
(2015)
Eine lebendige Innenstadt, ein schön buntes Warenangebot, eine tolle Atmosphäre – in der Realität sind Wochenmärkte attraktive Publikumsmagneten einer Stadt. Doch wie sieht dies in der virtuellen Welt aus?
Präsentieren die Wochenmärkte ihre Vorzüge und ihren Flair auch im Internet? Kümmern sich die Städte oder Kommunen um etwas Werbung für diese Attraktionen im Web? Dies scheint derzeit noch sehr unterschiedlich zu sein. Während einige Märkte eine Website pflegen, lassen sich über andere online oft nur die allerwichtigsten Informationen, wie die Öffnungszeiten, die Markttage und der Standort abrufen. Doch gerade die Dinge, die einen bestimmten Markt besonders auszeichnen und besuchenswert machen, werden häufig nicht erwähnt. Ein paar Bilder und Texte können den Charme eines Marktes auch im WWW transportieren.
In einer Zeit, in der das Internet immer bedeutender wird, vor allem für die jüngere Generation, sollte da nicht auch ein Wochenmarkt entsprechend durch diesen Kanal präsentiert werden? Dies ist die Einstiegsfrage dieser Ausarbeitung, die weitere Fragen aufwirft: Welche Gründe gibt es, dass ein Wochenmarkt im Internet dargestellt werden sollte? Ist dies seitens der Beteiligten, also einer Stadt oder den Marktbeschickenden, überhaupt gewünscht? Und wenn ja, wie könnte so eine Webpräsenz aussehen?
ZIELSETZUNG DER ARBEIT
Das Ziel dieser Bachelorarbeit war es deshalb, am Beispiel des Offenburger Wochenmarktes herauszufinden, was die Beteiligten dort zum Thema sagen und ob ein Webauftritt für den Markt aus ihrer Sicht erwünscht ist.
Dabei sollte auf den Ergebnissen aufbauend ein Konzept entwickelt werden, das eine attraktive und zukunftsfähige Webpräsenz hervorbringt, die nicht nach wenigen Jahren inaktuell und bedeutungslos ist.
Die Ausarbeitung richtet sich dabei nicht nur an die Akteurinnen und Akteure des Offenburger Wochenmarktes, sondern vielmehr an jede an einem Markt beteiligte Person, die sich fragt, ob eine Webpräsenz für einen Wochenmarkt sinnvoll ist. Auch die Personen, die sich damit beschäftigen, wie ein Internetauftritt aussehen kann, werden im Dokument Anregungen und Ideen dazu finden.
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.
Diese Arbeit beschäftigt sich mit den Grundlagen zu Multi-Agenten-Systemen in der Industrie. Der Begriff “Industrie 4.0“ wird eingeführt und es wird eingehend auf die Potentiale und Herausforderungen diesbezüglich eingegangen. Außerdem wird ein Überblick über aktuelle Entwicklungen und Ansätze zur Entwicklung von sogenannten autonomen Agenten gegeben. Diese werden auch im Hinblick auf die Themen Holonic Manufacturing und Multi-Agenten-System besprochen. Im praktischen Teil der Arbeit wird ein System bestehend aus vier BDI-Agenten ntwickelt, um einen beispielhaften Geschäftsprozess zu bearbeiten. Die Entwicklung basiert dabei auf Java und dem Jadex Agenten-Framework. Es wird gezeigt, dass sich damit autonome BDI-Agenten umsetzen lassen, die über Rechnergrenzen hinweg koordiniert werden können.
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.
Der Entwicklungsstatus des Internets und die daraus resultierenden, entstehenden Online-Marketing-Instrumente sind ein wichtiger Faktor bei der Entstehung von Weblogs. Der Blog ist zudem Bestandteil des Social-Media-Marketings, welches mittlerweile auch für Unternehmen unabdingbar ist. Blogs sind mittlerweile weltweit millionenfach vorhanden. Hieraus resultiert die Frage, wie sich eine Marketingstrategie für einen Lifestyle-Blog am effektivsten zusammensetzt. Welche Marketing- und Online-Marketing-Instrumente sollten verwendet werden und wie am besten kombiniert, um sich von der breiten Masse in der Blogosphäre abzuheben.
Die Betrachtung der theoretischen Grundlagen rund um die Themen Marketing, Online-Marketing und Blog, stellen die Basis für die Entwicklung einer Marketing-Strategie für einen Lifestyle-Blog namens „cotton & suede“ dar. Mit diversen Analysen und deren Auswertungen werden die Marktpositionierung und die Erfolgschancen des Blogs untersucht. Stück für Stück wird so eine Strategie entwickelt, die passende Instrumente kombiniert und sich somit zu einer Crossmedia-Strategie entwickelt.
Die Auswertungen zeigen, dass sich zukünftig überwiegend eine Mischung aus Social-Media-Marketing einstellen wird. Im Bereich des klassischen Marketings bezieht man sich ausschließlich auf die Kommunikationspolitik. Der Lifestyle-Blog „cotton & suede“ hat das Potenzial, eine weitreichende Zielgruppe anzusprechen und damit seinen Bekanntheitsgrad zu erhöhen und letztendlich kommerziell zu werden.
Adsorption of N2 and CO2 on Activated Carbon, AlO(OH) Nanoparticles, and AlO(OH) Hollow Spheres
(2015)
Adsorption behaviors of nitrogen and CO2 on Norit R1 Extra and AlO(OH) nanoparticles and hollow spheres were measured under different temperature and pressure conditions using a magnetic suspension balance. Independent from the substrate investigated, all isotherms increase at lower pressure, reach a maximum, and then decrease with increasing pressure. In addition, selected experimental data were correlated with different model approaches and compared with reliable literature data. In case of CO2 on AlO(OH), capillary condensation was observed at two defined temperatures. The results suggest that the conversion of the liquid into a supercritical adsorbate phase does not take place suddenly.
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.
Bauteilaktivierung
(2015)
Who is Who? Joseph Fourier
(2015)
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.
La industria del bacanora en Sonora, México, enfrenta la influencia de una compleja red de factores culturales, tecnológicos, económicos y legales que inhiben su desarrollo. Ello ocurre pese al esfuerzo institucional por radicar un marco normativo que elimine la práctica de los métodos informales de elaboración que derivan en calidades heterogéneas de licor. El conseguirlo se complica ante la dificultad que enfrentan los actores de esta industria para implementar prácticas efectivas de verificación de las normas vigentes en los confines de la geografía de la Denominación de Origen. En este documento se describe el uso de un prototipo de espectrómetro Raman por transformada de Fourier para analizar cualitativamente muestras desconocidas de bacanora. Este dispositivo se construyó con el uso de un interferómetro Michelson convencional, un contador de fotones de diseño propio y un foto-detector de referencia. Los resultados del trabajo confirman que dada su naturaleza de diseño y construcción, este instrumento de medición y su efectiva técnica de operación a bajo costo, constituye una alternativa viable, adaptable fácilmente a las necesidades de los actores productivos e institucionales, para asistirlos en la elaboración de bacanora y a la verificación de su calidad conforme a los criterios de la normatividad.
The Raman spectra from the chemical compounds toluene and cyclohexane obtained using a Fourier Transform (FT)-Raman spectrometer prototype have been contrasted with the Raman spectra of these same materials collected with two different commercial FT-Raman devices. The FT-Raman spectrometer consist of a Michelson interferometer, a self-designed photon counter and a reference photo-detector. The evaluation methodology of the spectral information, contrary to the commercial devices that commonly use the zero-crossing method, is carried out by re-sampling the Raman scattering and by accurately extracting the optical path information of the Michelson interferometer. The FTRaman arrangement has been built using conventional parts without disregarding the spectral frequency precision that usually such a FTRaman instruments deliver. No additional complex hardware components or costly software modules have been included in this FT-Raman device. The main Raman lines from the spectra obtained with the three FT-Raman devices have been compared with the Raman lines from the standard Raman spectra of these two materials. The values obtained using the FT-Raman spectrometer prototype have shown a frequency accuracy comparable to that obtained with the commercial devices without facing the need for a large investment. Although the proposed FT-Raman prototype cannot be directly compared to the last generation of FT-Raman spectrometers from the commercial manufacturers, such a device could give an opportunity to users that require high frequency precision in their spectral analysis and are provided with rather scarce resources.
Stromzustandsregelung
(2015)
Digital networked communications are the key to all Internet-of-Things applications, especially to smart metering systems and the smart grid. In order to ensure a safe operation of systems and the privacy of users, the transport layer security (TLS) protocol, a mature and well standardized solution for secure communications, may be used. We implemented the TLS protocol in its latest version in a way suitable for embedded and resource-constrained systems. This paper outlines the challenges and opportunities of deploying TLS in smart metering and smart grid applications and presents performance results of our TLS implementation. Our analysis shows that given an appropriate implementation and configuration, deploying TLS in constrained smart metering systems is possible with acceptable overhead.
We propose secure multi-party computation techniques for the distributed computation of the average using a privacy-preserving extension of gossip algorithms. While recently there has been mainly research on the side of gossip algorithms (GA) for data aggregation itself, to the best of our knowledge, the aforementioned research line does not take into consideration the privacy of the entities involved. More concretely, it is our objective to not reveal a node's private input value to any other node in the network, while still computing the average in a fully-decentralized fashion. Not revealing in our setting means that an attacker gains only minor advantage when guessing a node's private input value. We precisely quantify an attacker's advantage when guessing - as a mean for the level of data privacy leakage of a node's contribution. Our results show that by perturbing the input values of each participating node with pseudo-random noise with appropriate statistical properties (i) only a minor and configurable leakage of private information is revealed, by at the same time (ii) providing a good average approximation at each node. Our approach can be applied to a decentralized prosumer market, in which participants act as energy consumers or producers or both, referred to as prosumers.
Environmental Monitoring is an attractive application field for Wireless Sensor Network (WSN). Water Level Monitoring helps to increase the efficiency of water distribution and management. In Pakistan, the world’s largest irrigation system covers 90.000 km of channels which needs to be monitored and managed on different levels. Especially the sensor systems for the small distribution channels need to be low energy and low cost. The distribution presents a technical solution for a communication system which is developed in a research project being co-funded by German Academic Exchange Service (DAAD). The communication module is based on IEEE-802.15.4 transceivers which are enhanced through Wake-On-Radio (WOR) to combine low-energy and real-time behavior. On higher layers, IPv6 (6LoWPAN) and corresponding routing protocols like Routing Protocol for Low power and Lossy Networks (RPL) can extend range of the network. The data are stored in a database and can be viewed online via a web interface. Of course, also automatic data analysis can be performed.
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.
Durch den technischen Fortschritt werden sowohl die diagnostischen, als auch die therapeutischen Medizinprodukte immer komplexer. Gleichzeitig steigt auch der Funktionsumfang an, wodurch Krankheiten besser erkannt und behandelt werden können. Dabei muss das Gerät nicht nur funktional effektiv und sicher sondern auch einfach und intuitiv zu bedienen sein.
Aus diesem Grund muss beim Hersteller als letztes Glied des Entwicklungsprozesses die Produktvalidierung erfolgen. Um diese nach der erfolgreichen Verifizierung vollständig und effizient durchzuführen, wird in dieser Thesis zunächst die Datenanalyse der klinischen Bewertung aufgezeigt. Anschließend werden die Aufgabenanalyse und der Gebrauchstauglichkeitstest mit der Bewertung durch einen Fragebogen als Methoden der Usability-Validierung vorgestellt. Außerdem schließt die Produktvalidierung die Validierung der Lastenheftanforderungen mit ein, was mit Hilfe einer Dokumentenanalyse abgeprüft wird. Abschließend wird die Produktvalidierung in einem Dokument zusammengefasst und die Validität erklärt.
Zur Umsetzung der Validierungen werden am Beispiel eines mobilen EKG-Systems regularienkonforme Validierungsdokumente erörtert.
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.