Context-Awareness Enhances 5G Multi-Access Edge Computing Reliability

The fifth generation (5G) mobile telecommunication network is expected to support Multi- Access Edge Computing (MEC), which intends to distribute computation tasks and services from the central cloud to the edge clouds. Towards ultra-responsive, ultra-reliable and ultra-low-latency MEC services, the current mobile network security architecture should enable a more decentralized approach for authentication and authorization processes. This paper proposes a novel decentralized authentication architecture that supports flexible and low-cost local authentication with the awareness of context information of network elements such as user equipment and virtual network functions. Based on a Markov model for backhaul link quality, as well as a random walk mobility model with mixed mobility classes and traffic scenarios, numerical simulations have demonstrated that the proposed approach is able to achieve a flexible balance between the network operating cost and the MEC reliability.Comment: Accepted by IEEE Access on Feb. 02, 201

The recovery of biological particles in high-speed continuous centrifuges with special reference to feed-zone break-up effects

In the first part of this thesis the means are described by which an industrial disc stack centrifuge may be scaled-down to process in a meaningful fashion small volumes of particle suspensions. The centrifuge separation characteristics so measured were suitable for direct scale-up predictions of centrifuge performance. Experiments with a dye tracer and a reduced number of discs indicated that the flow through the disc centrifuge is influenced by the position of the separating discs within the disc stack. This influence was also reflected in the separation performance of a particulate suspension. The results were shown to be in the range obtained using a full-scale industrial disc centrifuge. Experiments also showed a distinct trend that the flow rate and in particular the single passage throughput influenced the separation performance. Using a non-linear curve-fitting algorithm it was shown that the grade efficiency curve of a disc centrifuge may be approximated by a two-parameter model equation. In the second part of this thesis the means are described by which various feed zones designs may be examined in respect to particle breakup using small volumes of a diluted protein precipitate suspension. It has been shown that in the high shear fields which are present in the feed zones to centrifuges the precipitate particles are readily disrupted into smaller fragments, the fragment size depending on the strength of the shear field. Examination of three different feed zone types revealed that particle breakup increased in the following order: full-hermetic < hydro-hermetic < semi-hermetic It has also been demonstrated that the bowl speed and in particular the rotational velocity of the distributor ribs has a significant influence on the level of particle breakup in the hydro-hermetic feed zone, while the effects were less pronounced in the full-hermetic feed zone. Based on the results obtained during the above studies the major mechanism of particle breakup is thought to be due to a combination of turbulence and collision of the particle suspension with the rotating distributor ribs. It has been shown that the level of particle breakup is directly related to the circumferential velocity of the distributor ribs

Leseaktivitäten auf großen, hochauflösenden Displays

In der heutigen Wissenschaft- und Geschäftswelt ist das Lesen und Verarbeiten großer Informationsmengen immer wichtiger geworden. Deswegen wird nach Lösungen zur Verbesserung der Informationserfassung und Informationsbearbeitung gesucht. Ein möglicher Ansatz ist der Einsatz großer, hochauflösender Displays. Mit Hilfe dieser Displays gibt es Möglichkeiten größere Informationsmengen auf einmal darstellen zu können. Das kann in paralleler Darstellung mehrerer Texte oder zusätzlicher Informationsebenen resultieren. Desweiteren sollen Alternativen zu herkömmlichen Eingabegeräten, wie Tastatur oder Maus, untersucht werden. Dabei kann der zukünftige Benutzer mit dem System interagieren, indem er Handbewegungen oder den Abstand zum Monitor als Hilfsmittel zur Interaktion nimmt. Die Bewegungen können von einem Bewegungserkennungssystem erfasst werden und die gewünschte Aktion ausführen. So kann der Abstand zwischen dem Benutzer und dem Monitor dazu genutzt werden, um die Schriftgröße zu beeinflussen. In dieser Arbeit wird der Einsatz große, hochauflösender Displays im Zusammenhang mit Textlesen und Textverstehen untersucht. Dabei wird insbesondere auf die verschiedenen Interaktionsmöglichkeiten, die sich aus der Kombination von großen, hochauflösenden Displays und Bewegungserkennungssystem entstehen, eingegangen. Auch die Darstellung des Textes und der Position des Lesers relativ zu den Displays soll auf Vorteile und Nachteile untersucht werden. Diesbezüglich wird eine Studie durchgeführt und ihre Ergebnisse statistisch erfasst und anschließend diskutiert werden

An efficient architecture for the integration of sensor and actuator networks into the future internet

In the future, sensors will enable a large variety of new services in different domains. Important application areas are service adaptations in fixed and mobile environments, ambient assisted living, home automation, traffic management, as well as management of smart grids. All these applications will share a common property, the usage of networked sensors and actuators. To ensure an efficient deployment of such sensor-actuator networks, concepts and frameworks for managing and distributing sensor data as well as for triggering actuators need to be developed. In this paper, we present an architecture for integrating sensors and actuators into the future Internet. In our concept, all sensors and actuators are connected via gateways to the Internet, that will be used as comprehensive transport medium. Additionally, an entity is needed for registering all sensors and actuators, and managing sensor data requests. We decided to use a hierarchical structure, comparable to the Domain Name Service. This approach realizes a cost-efficient architecture disposing of "plug and play" capabilities and accounting for privacy issues

Bayreuth : development and trends in a new university

Most people associate the city of Bayreuth with Richard Wagner, who lived there from 1872 until his death in 1883. It is, in fact, thanks to the annual Wagner festival, which has been held there since 1876, that Bayreuth became known throughout the world. Wagner apart, the city is the capital of the province of Upper Franconia in Bavaria. Situated about 40 miles north-north east of Nurnberg, it's a two hour drive from Munich, and has a population of roughly 70,000 inhabitants. The University occupies a very modern and still-growing campus on the outskirts of the town. The location of the campus is an indicator to the fact that the University of Bayreuth is very much a brand-new university, opened in the mid-seventies with the object of creating a new cultural centre. Siting the university in this part of Bavaria was indeed part of an effort to counter disadvantages inherent in Upper Franconia's regionalism. Being so newly-established, the University of Bayreuth, with a population of only 3000 students, is one of the smallest in Germany. This, however, is not without its advantages: smaller numbers of students make for more manageable lecture and study-groups and thus facilitate increased individual attention. Since one is not so exposed to the anonymity of mass lectures in overcrowded lecture-theatres, first-year students, fresh from the extremely structuralised and organised German secondary school system, find it easier to orientate into university life. It is easy to understand, on the other hand, that one cannot quite describe Bayreuth as a typical university town. Student life that has established roots and traditions over hundreds of years in towns like Heidelberg and Gottingen has yet to develop. Rather than deter prospective under-graduates keen on university life, this ought however to encourage students to make the most of initiative and creativity and help build up another university centre. Student attitudes, individual and collective, constitute the prime factor that determines the success or otherwise of university life and will be examined in greater detail further along in the article.peer-reviewe

Context-based user grouping for multi-casting in heterogeneous radio networks

Along with the rise of sophisticated smartphones and smart spaces, the availability of both static and dynamic context information has steadily been increasing in recent years. Due to the popularity of social networks, these data are complemented by profile information about individual users. Making use of this information by classifying users in wireless networks enables targeted content and advertisement delivery as well as optimizing network resources, in particular bandwidth utilization, by facilitating group-based multi-casting. In this paper, we present the design and implementation of a web service for advanced user classification based on user, network, and environmental context information. The service employs simple and advanced clustering algorithms for forming classes of users. Available service functionalities include group formation, context-aware adaptation, and deletion as well as the exposure of group characteristics. Moreover, the results of a performance evaluation, where the service has been integrated in a simulator modeling user behavior in heterogeneous wireless systems, are presented

Replica-Immunogold Technique Applied to Studies on Measles Virus Morphogenesis

The replica technique was applied to studies on the dynamic process of measles virus budding on infected HeLa cells. Virus structures were identified by labeling with anti-measles antibodies and protein A-gold. The combination of these two methods enabled us (1) to characterize the sequence of virus budding at the plasma membrane, (2) to localize virus structures on cytoskeletons of infected cells, and (3) to study the influence of Ca2+ ions on virus structures at the plasma membrane. Studies on platinum carbon surface replicas suggest that the process of virus budding is similar to the genesis of cellular microvilli. Replicas prepared from cytoskeletons of infected cells reveal a close association of budding virus with actin filaments composing the outer parts of the networks. Replicas of apical plasma membranes isolated from infected cells show the attachment of viral nucleocapsids to the protoplasmic membrane face of infected cells. These nucleocapsids are not present on membranes prepared from cells treated with calcium and the ionophore A23187. In addition viral cell surface antigens become randomly distributed on these cells. The data suggest that measles virus morphogenesis at the plasma membrane of cultured cells is dependent on the function of the cytoskeleton and may be influenced by Ca2+ ions