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Seismic excited liquid filled tanks are subjected to extreme loading due to hydrodynamic pressures, which can lead to nonlinear stability failure of the thinwalled cylindrical tanks, as it is known from past earthquakes. A significant reduction of the seismically induced loads can be obtained by the application of base isolation systems, which have to be designed carefully with respect to the modified hydrodynamic behaviour of the tank in interaction with the liquid. For this reason a highly sophisticated fluid-structure interaction model has to be applied for a realistic simulation of the overall dynamic system. In the following, such a model is presented and compared with the results of simplified mathematical models for rigidly supported tanks. Finally, it is examined to what extent a simple mechanical model can represent the behaviour of a base isolated tank in case of seismic excitation
Inference on the basis of high-dimensional and functional data are two topics which are discussed frequently in the current statistical literature. A possibility to include both topics in a single approach is working on a very general space for the underlying observations, such as a separable Hilbert space. We propose a general method for consistently hypothesis testing on the basis of random variables with values in separable Hilbert spaces. We avoid concerns with the curse of dimensionality due to a projection idea. We apply well-known test statistics from nonparametric inference to the projected data and integrate over all projections from a specific set and with respect to suitable probability measures. In contrast to classical methods, which are applicable for real-valued random variables or random vectors of dimensions lower than the sample size, the tests can be applied to random vectors of dimensions larger than the sample size or even to functional and high-dimensional data. In general, resampling procedures such as bootstrap or permutation are suitable to determine critical values. The idea can be extended to the case of incomplete observations. Moreover, we develop an efficient algorithm for implementing the method. Examples are given for testing goodness-of-fit in a one-sample situation in [1] or for testing marginal homogeneity on the basis of a paired sample in [2]. Here, the test statistics in use can be seen as generalizations of the well-known Cramérvon-Mises test statistics in the one-sample and two-samples case. The treatment of other testing problems is possible as well. By using the theory of U-statistics, for instance, asymptotic null distributions of the test statistics are obtained as the sample size tends to infinity. Standard continuity assumptions ensure the asymptotic exactness of the tests under the null hypothesis and that the tests detect any alternative in the limit. Simulation studies demonstrate size and power of the tests in the finite sample case, confirm the theoretical findings, and are used for the comparison with concurring procedures. A possible application of the general approach is inference for stock market returns, also in high data frequencies. In the field of empirical finance, statistical inference of stock market prices usually takes place on the basis of related log-returns as data. In the classical models for stock prices, i.e., the exponential Lévy model, Black-Scholes model, and Merton model, properties such as independence and stationarity of the increments ensure an independent and identically structure of the data. Specific trends during certain periods of the stock price processes can cause complications in this regard. In fact, our approach can compensate those effects by the treatment of the log-returns as random vectors or even as functional data.
When confining pressure is low or absent, extensional fractures are typical, with fractures occurring on unloaded planes in rock. These “paradox” fractures can be explained by a phenomenological extension strain failure criterion. In the past, a simple empirical criterion for fracture initiation in brittle rock has been developed. But this criterion makes unrealistic strength predictions in biaxial compression and tension. A new extension strain criterion overcomes this limitation by adding a weighted principal shear component. The weight is chosen, such that the enriched extension strain criterion represents the same failure surface as the Mohr–Coulomb (MC) criterion. Thus, the MC criterion has been derived as an extension strain criterion predicting failure modes, which are unexpected in the understanding of the failure of cohesive-frictional materials. In progressive damage of rock, the most likely fracture direction is orthogonal to the maximum extension strain. The enriched extension strain criterion is proposed as a threshold surface for crack initiation CI and crack damage CD and as a failure surface at peak P. Examples show that the enriched extension strain criterion predicts much lower volumes of damaged rock mass compared to the simple extension strain criterion.
This paper describes the potential for developing a digital twin of society- a dynamic model that can be used to observe, analyze, and predict the evolution of various societal aspects. Such a digital twin can help governmental agencies and policy makers in interpreting trends, understanding challenges, and making decisions regarding investments or policies necessary to support societal development and ensure future prosperity. The paper reviews related work regarding the digital twin paradigm and its applications. The paper presents a motivating case study- an analysis of opportunities and challenges faced by the German federal employment agency, Bundesagentur f¨ur Arbeit (BA), proposes solutions using digital twins, and describes initial proofs of concept for such solutions.
Industrial facilities must be thoroughly designed to withstand seismic actions as they exhibit an increased loss potential due to the possibly wideranging damage consequences and the valuable process engineering equipment. Past earthquakes showed the social and political consequences of seismic damage to industrial facilities and sensitized the population and politicians worldwide for the possible hazard emanating from industrial facilities. However, a holistic approach for the seismic design of industrial facilities can presently neither be found in national nor in international standards. The introduction of EN 1998-4 of the new generation of Eurocode 8 will improve the normative situation with
specific seismic design rules for silos, tanks and pipelines and secondary process components. The article presents essential aspects of the seismic design of industrial facilities based on the new generation of Eurocode 8 using the example of tank structures and secondary process components. The interaction effects of the process components with the primary structure are illustrated by means of the experimental results of a shaking table test of a three story moment resisting steel frame with different process components. Finally, an integrated approach of
digital plant models based on building information modelling (BIM) and structural health monitoring (SHM) is presented, which provides not only a reliable decision-making basis for operation, maintenance and repair but also an excellent tool for rapid assessment of seismic damage.
The fourth industrial revolution presents a multitude of challenges for industries, one of which being the increased flexibility required of manufacturing lines as a result of increased consumer demand for individualised products. One solution to tackle this challenge is the digital twin, more specifically the standardised model of a digital twin also known as the asset administration shell. The standardisation of an industry wide communications tool is a critical step in enabling inter-company operations. This paper discusses the current state of asset administration shells, the frameworks used to host them and their problems that need to be addressed. To tackle these issues, we propose an event-based server capable of drastically reducing response times between assets and asset administration shells and a multi-agent system used for the orchestration and deployment of the shells in the field.
Wir stellen hier exemplarisch STACK Aufgaben vor, die frei von der Problematik sind, welche sich durch diverse Kommunikationswege und (webbasierte) Computer Algebra Systeme (CAS) ergibt. Daher sind sie insbesondere für eine Open-Book Online Prüfung geeignet, da eine faire Prüfungssituation gewährleistet werden kann.
How does the implementation of a next generation network influence a telecommunication company?
(2009)
As the potential of a Next Generation Network (NGN) is recognized, telecommunication companies consider switching to it. Although the implementation of an NGN seems to be merely a modification of the network infrastructure, it may trigger or require changes in the whole company and even influence the company strategy. To capture the effects of NGN we propose a framework based on concepts of business engineering and technical recommendations for the introduction of NGN technology. The specific design of solutions for the layers "Strategy", "Processes" and "Information Systems" as well as their interdependencies are an essential characteristic of the developed framework. We have per-formed a case study on NGN implementation and observed that all layers captured by our framework are influenced by the introduction of an NGN.
Durch die Fragmentierung von Wertschöpfungsketten ergeben sich neue Herausforderungen für das Management von Kundenbeziehungen. Die Dissertation untersucht die daraus resultierenden Anforderungen an eine übergreifende Integration von Customer Relationship Management in der
Telekommunikationsindustrie. Ziel ist es, durch Anwendung von Methoden eines Enterprise Architecture Framework eine übergreifend Lösung zu gestalten. Grundlegende Prämisse dabei ist, dass die übergreifende Gestaltung eines Customer Relationship Management für alle an der
Wertschöpfung beteiligten Unternehmen vorteilhaft ist.
Market changes have forced telecommunication companies to transform their business. Increased competition, short innovation cycles, changed usage patterns, increased customer expectations and cost reduction are the main drivers. Our objective is to analyze to what extend transformation projects have improved the orientation towards the end-customers. Therefore, we selected 38 real-life case studies that are dealing with customer orientation. Our analysis is based on a telecommunication-specific framework that aligns strategy, business processes and information systems. The result of our analysis shows the following: transformation projects that aim to improve the customer orientation are combined with clear goals on costs and revenue of the enterprise. These projects are usually directly linked to the customer touch points, but also to the development and provisioning of products. Furthermore, the analysis shows that customer orientation is not the sole trigger for transformation. There is no one-fits-all solution; rather, improved customer orientation needs aligned changes of business processes as well as information systems related to different parts of the company.
Die Veränderungen des Telekommunikationsmarktes haben in der Praxis zu einer Vielzahl von Transformationsprojekten geführt. Was gehört aber zu einem “Transformationsprojekt”, welche Prozesse und Systeme werden verändert? Zur Beantwortung dieser Frage haben wir 184 Berichte zu Projekten analysiert, die als "Transformationsprojekte" bezeichnet waren. Für die Analyse haben wir einen Kodierungsrahmen konzipiert und anhand dessen die Berichte mit einem hierarchischen Clustering-Verfahren in Themen gruppiert. Die Ergebnisse liefern Hinweise über die in der Praxis gesetzten Schwerpunkte und Prioritäten. Sie können
somit als Unterstützung für Unternehmen dienen, die ein Transformationsprojekt planen. Sie weisen zudem darauf hin, in welchen Bereichen eines Unternehmens Unterstützung durch wissenschaftlich erprobte Werkzeuge und Modelle nötig ist.
Development of a subject-oriented reference process model for the telecommunications industry
(2016)
Generally the usage of reference models can be structured top-down or bottom-up. The practical need of agile change and flexible organizational implementation requires a consistent mapping to an operational level. In this context, well-established reference process models are typically structured top-down. The subject-oriented Business Process Management (sBPM) offers a modeling concept that is structured bottom-up and concentrates on the process actors on an
operational level. This paper applies sBPM to the enhanced Telecom Operations Map (eTOM), a well-accepted reference process model in the telecommunications industry. The resulting design artifact is a concrete example for a combination of a bottom-up and top-down developed reference model. The results are evaluated and confirmed in practical context through the involvement of the industry body TMForum.
Zur Unterstützung des Transformationsbedarfs von Telekommunikationsunternehmen sind die Referenzmodelle des TM Forums in der Praxis weltweit anerkannt. Dabei findet jedoch meist eine losgelöste Nutzung für spezifische Einzelthemen statt. Daher führt dieser Artikel die bestehenden Inhalte in einer industriespezifischen, übergreifenden Referenzarchitektur zusammen. Der Fokus liegt auf den Ebenen Aufbauorganisation, Prozesse, Applikationen und Daten. Darüber hinaus werden inhaltliche Architekturdomänen zur Strukturierung angeboten. Die Referenzarchitektur ist hierarchisch aufgebaut und wird hier beispielhaft für ausgewählte, aggregierte Inhalte beschrieben. Als erste Evaluation wird die Anwendung der Referenzarchitektur in drei Praxisprojekten erläutert.
The telecommunications industry is currently going through a major transformation. In this context, the enhanced Telecom Operations Map (eTOM) is a domain-specific process reference model that is offered by the industry organization TM Forum. In practice, eTOM is well accepted and confirmed as de facto standard. It provides process definitions and process flows on different levels of detail. This article discusses the reference modeling of eTOM, i.e., the design, the resulting artifact, and its evaluation based on three project cases. The application of eTOM in three projects illustrates the design approach and concrete models on strategic and operational levels. The article follows the Design Science Research (DSR) paradigm. It contributes with concrete design artifacts to the transformational needs of the telecommunications industry and offers lessons-learned from a general DSR perspective.
Primäre Ziele des Internets der Dinge sind die Steuerung physischer Gegenstände aus der Distanz und das Erfassen von Informationen aus dem Umfeld dieser Gegenstände. Dazu werden Hardwarekomponenten in Gegenstände des täglichen Lebens und die Umwelt integriert. Mithilfe von Informations- und Kommunikationstechnologien entsteht hieraus das Internet der Dinge (Internet of Things, IoT). Vor einem Jahr wurde mit Narrowband Internet of Things (NB-IoT) eine Technologie die es ermöglicht, Hardwarekomponenten energieeffizient und unmittelbar über das Mobilfunknetz zu vernetzen. Gegenstände werden dadurch über große Reichweiten eigenständig kommunikationsfähig. Das IoT steht mit NB-IoT vor einem gestiegenen Nutzenpotenzial, da eine zunehmende Anzahl miteinander verbundener Gegenstände und der Austausch größerer Datenmengen realisierbar sind. Damit sind aus wirtschaftlicher Sicht neue, innovative Anwendungsfälle des IoT möglich, die auch bereits in der Praxis diskutiert werden. In diesem Beitrag wird anhand eines konkreten Anwendungsfalls untersucht, welche neuen Geschäfts- bzw. Partnermodelle durch die gemeinsame Nutzung von NB-IoT-Daten und Big Data-Technologien entstehen und welcher qualitative Mehrwert für die an einem Anwendungsfall beteiligten Stakeholder geschaffen wird. Dazu wird – einem konstruktionsorientierten Forschungsansatz folgend – ein Bewertungsrahmen zur qualitativen Wertschöpfungsanalyse von NB-IoT entwickelt, der u.a. auf der Schablone nach Cockburn und dem Business Model Canvas basiert. Anhand dieses Bewertungsrahmens wird ein Anwendungsfall untersucht, der in anonymisierter Form an konkrete Praxisprojekte angelehnt ist. Konkret wird ein Anwendungsfall betrachtet, der einen Fahrradverleih 2.0 basierend auf dem Einsatz von NB-IoT vorschlägt. Aus den Untersuchungsergebnissen gehen beispielsweise Erkenntnisse hervor, wie Geschäftsmodelle auf
Kritische Infrastrukturen sind primäre Ziele krimineller Hacker. Der Deutsche Bundestag reagierte darauf am 25. Juli 2015 mit einem Gesetz zur Verbesserung der Sicherheit von ITSystemen, dem IT-Sicherheitsgesetz. Dies verlangt von Betreibern kritischer Infrastrukturen, angemessene Mindeststandards für organisatorische und technische Sicherheit zu implementieren, um den Betrieb und die Verfügbarkeit dieser Infrastruktur zu gewährleisten. Telekommunikationsunternehmen sind einerseits von diesem Gesetz in besonderem Maße betroffen und verfügen andererseits mit dem Rahmenwerk enhanced Telecom Operations Map (eTOM) über ein international anerkanntes Referenzmodell zur Gestaltung von Geschäftsprozessen in dieser Branche. Da sämtliche Telekommunikationsunternehmen in Deutschland verpflichtet sind, das Gesetz innerhalb eines bestimmten Zeitrahmens zu implementieren, präsentiert dieser Beitrag einen Vorschlag zur Erweiterung von eTOM um die relevanten Anforderungen des deutschen IT-Sicherheitsgesetzes.