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In any autonomous driving system, the map for localization plays a vital part that is often underestimated. The map describes the world around the vehicle outside of the sensor view and is a main input into the decision making process in highly complicated scenarios. Thus there are strict requirements towards the accuracy and timeliness of the map. We present a robust and reliable approach towards crowd based mapping using a GraphSLAM framework based on radar sensors. We show on a parking lot that even in dynamically changing environments, the localization results are very accurate and reliable even in unexplored terrain without any map data. This can be achieved by collaborative map updates from multiple vehicles. To show these claims experimentally, the Joint Graph Optimization is compared to the ground truth on an industrial parking space. Mapping performance is evaluated using a dense map from a total station as reference and localization results are compared with a deeply coupled DGPS/INS system.
Durch Industrie 4.0 kann die individuelle Fertigung von kleineren Stückzahlen zu geringen Kosten ermöglicht werden. Dafür müssen alle Anlagen miteinander vernetzt werden, um Daten austauschen und kommunizieren zu können. Durch die Vernetzung können neue Risiken und Gefahren entstehen. In dieser Arbeit wird die ITSicherheit in der Industrie 4.0 anhand möglichen Bedrohungsszenarien, Herausforderungen und Gegenmaßnahmen evaluiert. Dabei wird untersucht, welche Möglichkeiten Industrieunternehmen haben, um Hackerangriffen vorzubeugen und ob bereits etablierte Sicherheitskonzepte für industrielle Anlagen einfach übernommen werden können.
In den letzten Jahren beschäftigten sich Forscher und Automobilhersteller mit den Voraussetzungen für die Einführung von autonomem Fahren. Für Innovationen und Geschäftsmodelle im Bereich der intelligenten Mobilität, aber auch innerhalb der digitalen Wertschöpfungskette, spielen generell Zuverlässigkeit und Qualität der digitalen Datenübertragung eine entscheidende Rolle. Bevor das autonome Fahren vollständig eingeführt wird, muss man feststellen, welche Anforderungen an die digitale Infrastruktur beachtet werden müssen, gleichzeitig muss die Bedrohungslandschaft für autonomes Fahren analysiert werden.
Die folgende Arbeit beschäftigt sich damit, die Anforderungen und Gefahren zu analysieren und allgemeine Handlungsempfehlungen vorzuschlagen.
Im Rahmen der wissenschaftlichen Vertiefung soll auf Basis der vorhandenen Ansätze das IT-Risikomanagement evaluiert werden. Hierbei soll die Frage, inwiefern das IT-Risikomanagement dem Unternehmen eine Hilfestellung bieten kann, geklärt und anschließend anhand von zwei Fallbeispielen dargestellt werden.
Die digitale Zukunft zu definieren und zu gestalten ist in aller Munde - in der Industrie, der Lehre und so auch im Fokus der diesjährigen Informatics Inside Konferenz. Dazu gehören einerseits die Möglichkeiten, die die Digitalisierung mit sich bringt, z.B. beschrieben im Umfeld Krankenhaus oder in der Pferdezucht, andererseits die Schnittstelle zwischen realer und virtueller Welt, ausgeführt an Beispielen der Gesichts- und Bewegungserkennung. Auffällig ist, dass auch die Studierenden sich immer stärker auf die Sicherheit und Privatsphäre persönlicher Daten in einer digitalen Welt fokussieren. Dazu gehören fundamentale Sicherheitsuntersuchungen für ausgewählte Domänen, z.B. Industrie 4.0 oder Smart Home, wie auch die Betrachtung konkreter Einsatzszenarien, wie das autonome Fahren, die Kommunikation zwischen Fahrzeugen und dem neuen Personalausweis. Darüber hinaus stellen die Studierenden ihre Master-Projekte in Kurzbeiträgen vor.
Die Teilnehmer erfüllen nicht nur den Anspruch, die Ergebnisse ihrer Arbeit in schriftlicher Form anschaulich auszuarbeiten, sondern auch interaktiv vor ihrem Publikum zu verteidigen und zu diskutieren. Die Informatics Inside bietet somit ein Forum für Studierende, um während des Studiums zum einen die Ergebnisse ihrer Arbeit professionell einem interessierten Publikum zugänglich zu machen und zum anderen Anregungen anderer Vertiefungsgebiete aufzunehmen, aber auch die Arbeiten anderer kritisch zu hinterfragen.
Incubators in multinational corporations : development of a corporate incubator operator model
(2017)
This paper analyzes the components of a corporate incubator operator model in multinational companies. Thereby, three relevant phases were identified: pre incubation, incubation, and exit. Each phase contains different criteria that represent critical success factors for a corporate incubator, which are based on theoretical findings and lessons learned from practice. During the pre-incubation phase companies should define their need for a corporate incubator, the origin of ideas and the selection criteria for incubator tenants. The actual phase of incubation refers to the incubator program, which should be flexible with respect to each tenant. Furthermore, resource allocation plays an important role during the incubator program. Exit options after a successful incubation differ according to internal ideas and external start-ups, as well as the objective of the incubator. The research is based on a comprehensive screening of existing incubator literature and a qualitative content analysis of statements from eight experts of international corporate incubators.
In the present paper we demonstrate a novel approach to handling small updates on Flash called In-Place Appends (IPA). It allows the DBMS to revisit the traditional write behavior on Flash. Instead of writing whole database pages upon an update in an out-of-place manner on Flash, we transform those small updates into update deltas and append them to a reserved area on the very same physical Flash page. In doing so we utilize the commonly ignored fact that under certain conditions Flash memories can support in-place updates to Flash pages without a preceding erase operation.
The approach was implemented under Shore-MT and evaluated on real hardware. Under standard update-intensive workloads we observed 67% less page invalidations resulting in 80% lower garbage collection overhead, which yields a 45% increase in transactional throughput, while doubling Flash longevity at the same time. The IPA outperforms In-Page Logging (IPL) by more than 50%.
We showcase a Shore-MT based prototype of the above approach, operating on real Flash hardware – the OpenSSD Flash research platform. During the demonstration we allow the users to interact with the system and gain hands on experience of its performance under different demonstration scenarios. These involve various workloads such as TPC-B, TPC-C or TATP.
In recent times, enterprises have been increasingly dealing with the use of social media in internal communication and collaboration. In particular, so-called Enterprise Social Networks (ESN) promise meaningful benefits for the nature of work in corporations. However, these platforms often suffer from poor degrees of use. This raises the question of what initiatives enterprise can launch in order to stimulate the vitality of ESN. Since the use of ESN is often voluntary, individual adoption by employees need to be examined to find an answer. Therefore, the Unified Theory of Acceptance and Use of Technology (UTAUT) model was selected for the theoretical foundation of this paper. Following a qualitative research approach, the available research provides an analysis of expert interviews on specific ESN implementation strategies and included factors. In order to extensively conceptualize and generalize these strategic considerations, we conducted an inductive coding process. The results reveal that ESN implementation strategies can be understood as a multi-level construct (individual vs. group vs. organizational level) containing different factors dependent on the degree of documentation and intensity. This research in progress describes a qualitative evaluation as a preliminary study for further quantitative analysis of an ESN adoption model.
Software and system development faces numerous challenges of rapidly changing markets. To address such challenges, companies and projects design and adopt specific development approaches by combining well-structured comprehensive methods and flexible agile practices. Yet, the number of methods and practices is large, and available studies argue that the actual process composition is carried out in a fairly ad-hoc manner. The present paper reports on a survey on hybrid software development approaches. We study which approaches are used in practice, how different approaches are combined, and what contextual factors influence the use and combination of hybrid software development approaches. Our results from 69 study participants show a variety of development approaches used and combined in practice. We show that most combinations follow a pattern in which a traditional process model serves as framework in which several fine-grained (agile) practices are plugged in. We further show that hybrid software development approaches are independent from the company size and external triggers. We conclude that such approaches are the results of a natural process evolution, which is mainly driven by experience, learning, and pragmatism.
Software startups often make assumptions about the problems and customers they are addressing as well as the market and the solutions they are developing. Testing the right assumptions early is a means to mitigate risks. Approaches such as Lean Startup foster this kind of testing by applying experimentation as part of a constant build-measure-learn feedback loop. The existing research on how software startups approach experimentation is very limited. In this study, we focus on understanding how software startups approach experimentation and identify challenges and advantages with respect to conducting experiments. To achieve this, we conducted a qualitative interview study. The initial results show that startups often spent a disproportionate amount of time focusing on creating solutions without testing critical assumptions. Main reasons are the lack of awareness, that these assumptions can be tested early and a lack of knowledge and support on how to identify, prioritize and test these assumptions. However, startups understand the need for testing risky assumptions and are open to conducting experiments.
Medical applications are becoming increasingly important in the current development of health care and therefore a crucial part of the medical industry. An essential component is the development of user interfaces for mobile medical applications. The conceptual process is crucial for the further development of the main development process. Inconsistency or errors in the conceptual phase, have a serious impact on all areas and could prevent the certification for market approval.
This paper presents a guide to support developer with this process. It was developed based on a requirement analysis of the legal requirements to publish a medical device.
Im Februar 2011 wurden die Autoren von der Metropolitan School Frankfurt eingeladen, in einer vierstündigen Unterrichtseinheit die Grundlagen von systemischem Denken und System Dynamics einer vierten Klasse mit Kindern im Alter von 9 und 10 Jahren zu vermitteln. Inhaltlicher Themenschwerpunkt sollten Ökosysteme sein, die im Curriculum eine mehrwöchige Fokuslehreinheit bilden. Als Ergebnis eines Austauschs mit dem Klassenlehrer wurde der Fokus auf zwei Handlungsstränge gelegt: Räuber-Beute-Systeme sind für Viertklässler inhaltlich interessant und fügen sich passsend in die Unterrichtseinheit der Jahrgangstufe ein. Als weiteres, komplexeres Themengebiet wurd der Klimawandel gewählt. Beide Themen haben den gewünschten inhaltlichen Bezug zum Schwerpunkt "Ökosysteme".
Under update intensive workloads (TPC, LinkBench) small updates dominate the write behavior, e.g. 70% of all updates change less than 10 bytes across all TPC OLTP workloads. These are typically performed as in-place updates and result in random writes in page-granularity, causing major write-overhead on Flash storage, a write amplification of several hundred times and lower device longevity.
In this paper we propose an approach that transforms those small in-place updates into small update deltas that are appended to the original page. We utilize the commonly ignored fact that modern Flash memories (SLC, MLC, 3D NAND) can handle appends to already programmed physical pages by using various low-level techniques such as ISPP to avoid expensive erases and page migrations. Furthermore, we extend the traditional NSM page-layout with a delta-record area that can absorb those small updates. We propose a scheme to control the write behavior as well as the space allocation and sizing of database pages.
The proposed approach has been implemented under Shore- MT and evaluated on real Flash hardware (OpenSSD) and a Flash emulator. Compared to In-Page Logging it performs up to 62% less reads and writes and up to 74% less erases on a range of workloads. The experimental evaluation indicates: (i) significant reduction of erase operations resulting in twice the longevity of Flash devices under update-intensive workloads; (ii) 15%-60% lower read/write I/O latencies; (iii) up to 45% higher transactional throughput; (iv) 2x to 3x reduction in overall write
amplification.
Layout generators, commonly denoted as PCells (parameterized cells), play an important role in the layout design of analog ICs (integrated circuits). PCells can automatically create parts of a layout, whose properties are controlled by the PCell parameters. Any layout, whether hand-crafted or automatically generated, has to be verified against design rules using a DRC (design rule check) in order to assure proper functionality and producibility. Due to the growing complexity of today’s PCells it would be beneficial if a PCell itself could be ensured to produce DRC clean layouts for any allowed parameter values, i.e. a formal verification of the PCell’s code rather than checking all possible instances of the PCell. In this paper we demonstrate the feasibility of such a formal PCell verification for a simple NMOS transistor PCell. The set from which the parameter values can be chosen was found during the verification process.
The ability to develop and deploy high-quality software at a high speed gets increasing relevance for the comptetitiveness of car manufacturers. Agile practices have shown benefits such as faster time to market in several application domains. Therefore, it seems to be promising to carefully adopt agile practices also in the automotive domain. This article presents findings from an interview-based qualitative survey. It aims at understanding perceived forces that support agile adoption. Particularly, it focuses on embedded software development for electronic control units in the automotive domain.
First International Workshop on Hybrid dEveLopmENt Approaches in Software Systems Development
(2017)
A software process is the game plan to organize project teams and run projects. Yet, it still is a challenge to select the appropriate development approach for the respective context. A multitude of development approaches compete for the users’ favor, but there is no silver bullet serving all possible setups. Moreover, recent research as well as experience from practice shows companies utilizing different development approaches to assemble the bestfitting approach for the respective company: a more traditional process provides the basic framework to serve the organization, while project teams embody this framework with more agile (and/or lean) practices to keep their flexibility. The first HELENA workshop aims to bring together the community to discuss recent findings and to steer future work.
Pokémon Go was the first mobile Augmented Reality (AR) game that made it to the top of the download charts of mobile applications. However, very little is known about this new generation of mobile online Augmented Reality (AR) games. Existing media usage and technology acceptance theories provide limited applicability to the understanding of its users. Against this background, this research provides a comprehensive framework that incorporates findings from uses & gratification theory (U>), technology acceptance and risk research as well as flow theory. The proposed framework aims at explaining the drivers of attitudinal and intentional reactions, such as continuance in gaming or willingness to conduct in-app purchases. A survey among 642 Pokémon Go players provides insights into the psychological drivers of mobile AR games. Results show that hedonic, emotional and social benefits, and social norms drive, vice versa physical risks (but not privacy risks) hinder consumer reactions. However, the importance of these drivers differs between different forms of user behavior.
Ein stark erforschtes Gebiet der Computer Vision ist die Detektion von markanten Punkten des Gesichtszuges (englisch: facial feature detection), wie der Mundwinkel oder des Kinns. Daher lassen sich eine Vielzahl von veröffentlichten Verfahren finden, die sich jedoch teils deutlich hinsichtlich der Detektionsgenauigkeit, Robustheit und Geschwindigkeit unterscheiden. So sind viele Verfahren nur bedingt echtzeitfähig oder liefern nur mit hochaufgelösten Bildquellen ein zufriedenstellendes Ergebnis. In den letzten Jahren wurden daher Verfahren entwickelt, die versuchen, diese Problematiken zu lösen. In dieser Arbeit erfolgt eine Betrachtung dreier dieser State-of-the-Art Verfahren: Constrained Local Neural Fields (CLNF), Discriminative Response Map Fitting (DRMF) und Structured Output SVM (SO SVM), sowie deren Implementierungen. Dazu erfolgt ein empirischer Vergleich hinsichtlich der Detektionsgenauigkeit.
Entwicklung eines nicht vergilbenden, faserbasierten BH's mittels innovativer FIM-Technologie
(2017)
Electronic word-of-mouth (eWoM) communication plays an increasingly important role in modern business. The underlying concept of word-of-mouth (WoM) communication is well researched and has proved highly significant in respect of its impact on customers purchase behavior. However, due to the advent of digital technologies, decision-making among customers is progressively shifting to the online world. Consequently, eWoM has received a lot of attention from the academic community. As multiple research papers focus on specific facets of eWoM, there is a need to integrate current research results systematically. Thus, this paper presents a scientific literature analysis in order to determine the current state-of-the-art in the field of eWoM. Five main research areas were analyzed, supporting the need for further eWoM studies and providing a structured overview of existing results.
Es wird gezeigt, wie bei Fernspeisung die Vorhersage der Erwärmung mit entsprechender Modellierung verbessert werden kann und wie der Einfluss von Material und Form des Kabelkanals die Erwärmung und das das Temperaturprofil des Bündels beeinflusst. Es wird auch vorgestellt, dass die erhöhte Erwärmung von Metallkabelkanälen auf die geringere Emissivität zurückzuführen ist und wie das verbessert werden kann.
In this paper we build on our research in data management on native Flash storage. In particular we demonstrate the advantages of intelligent data placement strategies. To effectively manage phsical Flash space and organize the data on it, we utilize novel storage structures such as regions and groups. These are coupled to common DBMS logical structures, thus require no extra overhead for the DBA. The experimental results indicate an improvement of up to 2x, which doubles the longevity of Flash SSD. During the demonstration the audience can experience the advantages of the proposed approach on real Flash hardware.
Integrierte Schaltkreise (IC) sind ein integraler Bestandteil vieler Geräte wie zum Beispiel Smartphones, Computer oder Fernseher. Auf den Schaltkreisen werden immer mehr Funktionen integriert. Um die Arbeit auch zukünftig in gegebener Zeit bewältigen zu können, bedarf es daher einer Möglichkeit für die gleichzeitige Zusammenarbeit der Entwickler. Unter dem Arbeitstitel eCEDA (eCollaboration for Electronic Design Automation) wird ein Konzept für eine Webanwendung entwickelt, die die Echtzeitkollaboration von Entwicklern im Chipentwurf ermöglichen soll. Dieses Konzept sowie verschiedene Aspekte der Kollaboration werden in dieser Arbeit behandelt.
A concept for a slope shaping gate driver IC is proposed, used to establish control over the slew rates of current and voltage during the turn-on and turn off switching transients.
It combines the high speed and linearity of a fully-integrated closed-loop analog gate driver, which is able to perform real-time regulation, with the advantages of digital control, like flexibility and parameter independency, operating in a predictive cycle-bycycle regulation. In this work, the analog gate drive integrated circuit is partitioned into functional blocks and modeled in the small-signal domain, which also includes the non-linearity of parameters. An analytical stability analysis has been performed in order to ensure full functionality of the system controlling a modern generation IGBT and a superjunction MOSFET. Major parameters of influence, such as gate resistor and summing node capacitance, are investigated to achieve stable control. The large-signal behavior, investigated by simulations of a transistor level design, verifies the correct operation of the circuit. Hence, the gate driver can be designed for robust operation.
In 2016, German car manufacturer the Audi Group (AUDI AG) was working on an expanding array of digital innovations. The goals of these innovations varied, and included strengthening customer- and employee-facing processes, digitally enhancing existing products, and developing new, potentially disruptive business models. Audi’s IT unit was critical to each of these efforts. Based on personal interviews with 11 IT- and non-IT executives at Audi, this case examines the different ways in which digitization can help to enhance and transform an organization’s processes, products, and business models. The case also highlights the challenges that arise as large companies “digitize.”
Recent digital technologies like the Internet of Things and Augmented Reality have brought IT into companies’ core products. What were previously purely physical products are becoming hybrid or digitized. Despite receiving a lot of recent attention, digitized products have only seen a slow uptake in businesses so far. In this paper, we study the challenges that keep companies from realizing the desired impacts of digitized products and the practices they employ to address these challenges. To do so, we looked at companies from a set of industries that are highly affected by digital transformation, but at the same time hesitant to move to a more digitized world: the creative industries. Based on a literature review and twelve interviews in creative industries, we developed a conceptual model that can serve as a basis for formulating testable hypotheses for further research in this area.
Digitization in the energy sector is a necessity to enable energy savings and energy efficiency potentials. Managing decentralized corporate energy systems is hindered by a non-existence. The required integration of energy objectives into business strategy creates difficulties resulting in inefficient decisions. To improve this, practice-proven methods such as Balanced Scorecard, Enterprise Architecture Management and the Value Network approach are transferred to the energy domain. The methods are evaluated based on a case study. Managing multi-dimensionality, high complexity and multiple actors are the main drivers for an effective and efficient energy management system. The underlying basis to gain the positive impacts of these methods on decentralized corporate energy systems is digitization of energy data and processes.
Digitization will require companies to fundamentally reengineer their sales processes. Adapting the concept of value selling to the digital age will enable them to deliver superior value to their customers. Specifically, social selling will provide them with an answer to the ever-increasing complexity of customer journeys. This article, based on a survey among 235 German companies, assesses the status quo and outlines opportunities. Moreover, it introduces a novel approach for developing well-grounded social selling metrics.
The third Digital Enterprise Computing Conference DEC 17 at the Herman Hollerith Center in Böblingen brings together students, researchers, and practitioners to discuss solutions, experiences, and future developments for the digital transformation. Digitization of business and IT defines the conference agenda: digital models & architecture, digital marketing, agility & innovation.
Im Rahmen der wissenschaftlichen Vertieung werden unterschiedliche empirische Forschungsmethoden erörtert.
Im ersten Schritt werden die Grundlagen der empirischen Forschungsmethoden ermittelt und klassifiziert. Nach der Klassifikation der Forschungsmethoden werden zwei Forschunsmethoden angewandt. Die Auswahl der Methoden fällt auf die quantitative und qualitative Forschungsmethode.
Diese Forschungsmethoden werden während der Analysephase eingesetzt, um den weltweiten Ist-Zustand der Tochtergesellschaften zu ermitteln. Hierbei geht es um die Analyse des Import- und Export-Prozesses bei den Tochtergesellschaften der HUGO BOSS AG. Ziel ist es, die Ergebnisse für die Master Thesis einzusetzen. Anhand der Ergebnisse können Gemeinsamkeiten oder auch Abweichungen im Zollabwicklungsprozess aufgezeigt werden, die später in der Konzeption berücksichtigt werden.
Hierzu wird die qualitative Methode eingesetzt, welche die Basis für die Konzeptionierung der Umfrage liefert. Abschließend wurde für die Verifikation der Ergebnisse die qualitative Methode für die Interviews eingesetzt.
Clinical reading centers provide expertise for consistent, centralized analysis of medical data gathered in a distributed context. Accordingly, appropriate software solutions are required for the involved communication and data management processes. In this work, an analysis of general requirements and essential architectural and software design considerations for reading center information systems is provided. The identified patterns have been applied to the implementation of the reading center platform which is currently operated at the Center of Ophthalmology of the University Hospital of Tübingen.
In this paper we describe the design and development process of an electromagnetic picker for rivets. These rivets are used in a production process of leather or textile design objects like riveted waist belts or purses. The picker is designed such that it replaces conventional mechanical pickers thus avoiding mechanical wear problems and increasing the process quality. The paper illustrates the challenges in the design process of this mechatronic system. The design process was based on both simulation and experiments leading to a prototype that satisfies the requirements.
Mittlerweile ist der Einsatz von technischen Hilfsmitteln zu Analysezwecken im Sport fester Bestandteil im Trainingsalltag von Trainern und Athleten. In nahezu jeder Sportart werden Videoaufzeichnungen genutzt, um die Bewegungsausführung zu dokumentieren und zu analysieren. Allerdings reichen Aufnahmen von einem statischen Standort oftmals nicht mehr aus. An dieser Stelle kann Virtual Reality (VR) eine Lösung dieses Problems bieten. Durch VR kann der aufgezeichneten Szene eine weitere Ebene hinzugefügt und die Bewegungsabläufe neu und detaillierter bewertet werden. Um Bewegungen in einer virtuellen Umgebung abzubilden, müssen diese mittels Motion Capturing (MoCap) aufgezeichnet werden. Ziel dieser Arbeit ist es, herauszufinden, ob das MoCap System Perception Neuron in der Lage ist, Bewegungen in hoher Geschwindigkeit zu erfassen.
Digitization fosters the development of IT environments with many rather small structures, like Internet of Things (IoT), microservices, or mobility systems. They are needed to support flexible and agile digitized products and services. The goal is to create service-oriented enterprise architectures (EA) that are self optimizing and resilient. The present research paper investigates methods for decision-making concerning digitization architectures for Internet of Things and microservices. They are based on evolving enterprise architecture reference models and state of the art elements for architectural engineering for microgranular systems. Decision analytics in this field becomes increasingly complex and decision support, particularly for the development and evolution of sustainable enterprise architectures, is sorely needed. The challenging of the decision processes can be supported with in a more flexible and intuitive way by an architecture management cockpit.
The Ninth International Conference on Advances in Databases, Knowledge, and Data Applications (DBKDA 2017), held between May 21 - 25, 2017 - Barcelona, pain, continued a series of international events covering a large spectrum of topics related to advances in fundamentals on databases, evolution of relation between databases and other domains, data base technologies and content processing, as well as specifics in applications domains databases.
Advances in different technologies and domains related to databases triggered substantial improvements for content processing, information indexing, and data, process and knowledge mining. The push came from Web services, artificial intelligence, and agent technologies, as well as from the generalization of the XML adoption.
High-speed communications and computations, large storage capacities, and load-balancing for distributed databases access allow new approaches for content processing with incomplete patterns, advanced ranking algorithms and advanced indexing methods.
Evolution on e-business, ehealth and telemedicine, bioinformatics, finance and marketing, geographical positioning systems put pressure on database communities to push the ‘de facto’ methods to support new requirements in terms of scalability, privacy, performance, indexing, and heterogeneity of both content and technology.
Data Integration of heterogeneous data sources relies either on periodically transferring large amounts of data to a physical Data Warehouse or retrieving data from the sources on request only. The latter results in the creation of what is referred to as a virtual Data Warehouse, which is preferable when the use of the latest data is paramount. However, the downside is that it adds network traffic and suffers from performance degradation when the amount of data is high. In this paper, we propose the use of a readCheck validator to ensure the timeliness of the queried data and reduced data traffic. It is further shown that the readCheck allows transactions to update data in the data sources obeying full Atomicity, Consistency, Isolation, and Durability (ACID) properties.
The increasing number of connected mobile devices such as fitness trackers and smartphones define new data for health insurances, enabling them to gain deeper insights into the health of their customers. These additional data sources plus the trend towards an interconnected health community, including doctors, hospitals and insurers, lead to challenges regarding data filtering, organization and dissemination. First, we analyze what kind of information is relevant for a digital health insurance. Second, functional and non-functional requirements for storing and managing health data in an interconnected environment are defined. Third, we propose a data architecture for a digitized health insurance, consisting of a data model and an application architecture.
The diversity of energy prosumer types makes it difficult to create appropriate incentive mechanisms that satisfy both prosumers and energy system operators alike. Meanwhile, European energy suppliers buy guarantees of origin (GoO) which allow them to sell green energy at premium prices while in reality delivering grey energy to their customers. Blockchain technology has proven itself to be a robust paying system in which users transact money without the involvement of a third party. Blockchain tokens can be used to represent a unit of energy and, just as GoOs, be submitted to the market. This paper focuses on simulating marketplace using the ethereum blockchain and smart contracts, where prosumers can sell tokenized GoOs to consumers willing to subsidize renewable energy producers. Such markets bypass energy providers by allowing consumers to obtain tokenized GoOs directly from the producers, which in turn benefit directly from the earnings. Two market strategies where tokens are sold as GoOs have been simulated. In the Fix Price Strategy prosumers sell their tokens to the average GoO price of 2014. The Variable Price Strategy focuses on selling tokens at a price range defined by the difference between grey and green energy. The study finds that the ethereum blockchain is robust enough to functions as a platform for tokenized GoO trading. Simulation results have been compared and the results indicate that prosumers earn significantly more money by following the Variable Price
Strategy.
Condition Monitoring for mechanical systems like bearings or transmissions is often done by analysing frequency spectra obtained from accelerometers mounted to the components under observation. Although this approach gives a high amount on information about the system behaviour, the interpretation of the resulting spectra requires expert knowledge, that is, a deep understanding of the effect on condition deterioration on the measured spectra. However, an increasing number of condition monitoring applications demands other representations of the measured signals that can be easily interpreted even by non–experts. Therefore, the objective of this paper is to develop an approach for processing measured process data in order to obtain an easy to interpret measure for assessing the component condition. The main idea is to evaluate the deterioration of a component condition by computing the correlation function of current measurements with past measurements in order to detect a component condition deterioration from a change in these correlation functions. Besides the simplicity of the obtained measure, this approach opens the opportunity for integrating a model based approach as well. The developed method is tested based on a condition monitoring application in a roller chain.
This paper describes a new method for condition monitoring of a roller chain. In contrast to conventional methods, no additional accelerometers are used to measure and interpret frequency spectra but the chain condition is evaluated using an easy to interpret similarity measure based on correlation functions using the driving motor torque. An additional clustering of current data and reference measurements yields an easy to understand representation of the chain condition.
With the Internet of Things being one of the most discussed trends in the computer world lately, many organizations find themselves struggling with the great paradigm shift and thus the implementation of IoT on a strategic level. The Ignite methodoogy as a part of the Enterprise-IoT project promises to support organizations with these strategic issues as it combines best practices with expert knowledge from diverse industries helping to create a better understanding of how to transform into an IoT driven business. A framework that is introduced within the context of IoT business model development is the Bosch IoT Business Model Builder. In this study the provided framework is compared to the Osterwalder Business Model Canvas and the St. Gallen Business Model Navigator, the most commonly used and referenced frameworks according to a quantitative literature analysis.
To analyze the humans’ sleep it is necessary as to identify the sleep stages, occurring during the sleep, their durations and sleep cycles. The gold standard procedure for this approach is polysomnography (PSG), which classify the sleep stages based on Rechtschaffen and Kales (R-K) method. This method aside the advantages as high accuracy has however some disadvantages, among others time-consuming and uncomfortable for the patient procedure. Therefore, the development of further methods for the sleep classification in addition to PSG is a promising topic for the investigation and this work has as its aim the presentation of possible ways and goals for this development.
This paper investigates the impact of dynamic capabilities (DC) on brand love. From a resource-based view, there is little clarity vis-à-vis the specific capabilities that drive the ability to create brand love. This paper focuses on three research questions: Firstly, which dynamic capabilities are relevant for brand love? Secondly, how strong is the impact of certain dynamic capabilities on brand love? Thirdly, which conditions mediate and moderate the impact of specific dynamic capabilities on brand love? Data from a multi-method research approach have been used to itentify the specific capabilities that corporations need, to enhance brand love. Furthermore, a standardized online survey was conducted on marketing executives and evaluated by structural equation modeling. The results indicate, that customer expertise plays a major role in the relationship between dynamic capabilities and brand love. Furthermore, this relationship is more important in markets that have a low competitive differentiation in products and services.
The main challenge when driving heat pumps by PV-electricity is balancing differing electrical and thermal demands. In this article, a heuristic method for optimal operation of a heat pump driven by a maximum share of PV-electricity is presented. For this purpose, the (DHW) are activated in order shift the operation of the heat pump to times of PV-generation. The system under consideration refers to thermal and electrical demands of a single family house. It consists of a heat pump, a thermal energy storage for DHW and of grid connected heating and generation of domestic hot water, the heat pump runs with two different supply temperatures and thereby achieving a maximum overall COP. Within the algorithm for optimization a set of heuristic rules is developed in a way that the operational characteristics of the heat pump in terms of minimum running and stopping times are met as well as the limiting constraints of upper and lower limits of room temperature and energy content of electricity generated, a varying number of heat pump schedules fulfilling the bundary conditions are created. Finally, the schedule offering the maximum on-site utilization of PV-electricity with a minimum number of starts of the heat pump, which serves as secondary condition, is selected. Yearly simulations of this combination have been carried out. Initial results of this method indicate a significant rise in on-site consumption of the PV-electricity and heating demand fulfilment by renewable electricity with no need for a massive TES for the heating system in terms of a big water tank.
This paper contributes to the automatic detection of perioperative workflow by developing a binary endoscope localization. Automated situation recognition in the context of an intelligent operating room requires the automatic conversion of low level cues into more abstract high level information. Imagery from a laparoscope delivers rich content that is easy to obtain but hard to process. We introduce a system which detects if the endoscope's distal tip is inside or outsiede the patient based on the endoscope video. This information can be used as one parameter in a situation recognition pipeline. Our localization performs in real-time at a video resolution of 1280x720 and 5-fold cross validation yields mean F1-scores of up to 0,94 on videos of 7 laparoscopies.
In a time of digital transformation, the ability to quickly and efficiently adapt software systems to changed business requirements becomes more important than ever. Measuring the maintainability of software is therefore crucial for the long-term management of such products. With service-based systems (SBSs) being a very important form of enterprise software, we present a holistic overview of such metrics specifically designed for this type of system, since traditional metrics – e.g. object oriented ones – are not fully applicable in this case. The selected metric candidates from the literature review were mapped to 4 dominant design properties: size, complexity, coupling, and cohesion. Microservice-based systems (μSBSs) emerge as an agile and fine grained variant of SBSs. While the majority of identified metrics are also applicable to this specialization (with some limitations), the large number of services in combination with technological heterogeneity and decentralization of control significantly impacts automatic metric collection in such a system. Our research therefore suggests that specialized tool support is required to guarantee the practical applicability of the presented metrics to μSBSs.
Painting galleries typically provide a wealth of data composed of several data types. Those multivariate data are too complex for laymen like museum visitors to first, get an overview about all paintings and to look for specific categories. Finally, the goal is to guide the visitor to a specific painting that he wishes to have a more closer look on. In this paper we describe an interactive visualization tool that first provides such an overview and lets people experiment with the more than 41,000 paintings collected in the web gallery of art. To generate such an interactive tool, our technique is composed of different steps like data handling, algorithmic transformations, visualizations, interactions, and the human user working with the tool with the goal to detect insights in the provided data. We illustrate the usefulness of the visualization tool by applying it to such characteristic data and show how one can get from an overview about all paintings to specific paintings.
This paper reports an analysis of application and impact of FMEA on susceptibility of generic IT-networks. It is not new that in communication system, the frequency and the data transmission rate play a very important role. The rapid increase in miniaturization of electronic devices leads to very sensitivity against electromagnetic interference. Since the IT network with the data transfer rate makes a huge contribution to this development it is very important to monitor their functionality. Therefore, tests are performed to observe and ensure the data transfer rate of IT networks against IEMI. A fault tree model is presented and observed effects during radiation of disturbance on complex system by a HPEM interference sources are described using a continuous and consistent model of the physical layer to the application layer.
Anforderungen an die Mensch-Maschine-Schnittstelle im Automobil auf dem Weg zum autonomen Fahren
(2017)
In den letzten Jahrzehnten haben immer mehr Fahrerassistenzsysteme Einzug in das Automobil gefunden und bereiten damit den Weg zu vollautonomen Fahrzeugen der Zukunft vor. So bieten bereits viele Hersteller Ausstattungsvarianten ihrer Fahrzeuge an, die für den Umstieg in die vollautonome Zukunft gewappnet sind. Um den Menschen mit auf den Weg zu nehmen, werden einige Anforderungen an die Mensch-Maschine-Schnittstelle (MMS) des Automobils gestellt. Für die teilautonomen Fahrzeuge der nächsten Generation gilt es, den Fahrerwechsel zwischen manuellem und autonomen Fahren für die Menschen bestmöglich zu gestalten. Die Arbeit wirft einen Blick auf ausgewählte Ansätze für zukünftige MMS-Systeme und bewertet diese anhand der Übergabezeiten zwischen Mensch und Maschine. Ein Wandel der MMS im Automobil wird empfohlen, um den Menschen mit den neuen Technologien vertraut zu machen.
In der Medizin existieren verschiedene Reifegradmodelle, die die Digitalisierung von Krankenhäusern unterstützen können. Die Anforderungen an ein Reifegradmodell für diesen Zweck umfassen Aspekte aus allgemeinen und spezifischen Bereichen des Krankenhauses. Die Analyse der Reifegradmodelle HIN, CCMM, EMRAM und O-EMRAM zeigt große Lücken im Bereich des OP sowie fehlende Aspekte in der Notaufnahme auf. Ein umfassendes Reifegradmodell wurde nicht gefunden. Durch eine Kombination aus HIN und CCMM könnten fast alle Bereiche ausreichend abgedeckt werden. Zusätzliche Ergänzungen durch spezialisierte Reifegradmodelle oder sogar die Entwicklung eines umfassenden Reifegradmodells wären sinnvoll.
Die Arbeit stellt die Möglichkeiten von 3D-Controllern für den Einsatz in der interventionellen Radiologie und insbesondere für die Steuerung der Echtzeit-Magnetresonanztomographie (MRT) dar. Dies ist interessant in Bezug auf die kontrollierte Navigation in ein Zielgewebe. Dabei kann der Interventionalist durch Echtzeit- Bildgebung den Verlauf des Eingriffs verfolgen, allerdings kann er bisher das MRT während der Durchführung des Eingriffs nicht selbst steuern, da dies durch den Assistenten im Nebenraum erfolgt. Die Kommunikation ist bei dem hohen Geräuschpegel aber sehr schwer. Diese Arbeit setzt an dieser Stelle an und analysiert 3D-Controller auf die Eignung für die Echtzeit-Steuerung eines MRTs. Dabei wurden trackingbasierte und trackinglose Geräte betrachtet. Als Ergebnis ließ sich festhalten, dass trackingbasierte Verfahren weniger geeignet sind, aufgrund der nicht ausreichenden Interpretation der Eingaben. Die trackinglosen Geräte hingegen sind aufgrund der korrekten Interpretation aller Eingaben und der intuitiven Bedienung geeignet.
Gallium nitride high electron mobility transistors (GaN-HEMTs) have low capacitances and can achieve low switching losses in applications where hard turn-on is required. Low switching losses imply a fast switching; consequently, fast voltage and current transients occur. However, these transients can be limited by package and layout parasitics even for highly optimized systems. Furthermore, a fast switching requires a fast charging of the input capacitance, hence a high gate current.
In this paper, the switching speed limitations of GaN-HEMTs due to the common source inductance and the gate driver supply voltage are discussed. The turn-on behavior of a GaN-HEMT is simulated and the impact of the parasitics and the gate driver supply voltage on the switching losses is described in detail. Furthermore, measurements are performed with an optimized layout for a drain-source voltage of 500 V and a drain-source current up to 60 A.
The demonstration project Virtual Power Plant Neckar-Alb is constructing a Virtual Power Plant (VPP) demonstration site at the Reutlingen University campus. The VPP demonstrator integrates a heterogeneous set of distributed energy resources (DERs) which are connected to control the infrastructure and an energy management system. This paper describes the components and the architecture of the demonstrator and presents strategies for demonstration of multiple optimization and control systems with different control paradigms.
Sleep quality and in general, behavior in bed can be detected using a sleep state analysis. These results can help a subject to regulate sleep and recognize different sleeping disorders. In this work, a sensor grid for pressure and movement detection supporting sleep phase analysis is proposed. In comparison to the leading standard measuring system, which is Polysomnography (PSG), the system proposed in this project is a non invasive sleep monitoring device. For continuous analysis or home use, the PSG or wearable actigraphy devices tends to be uncomfortable. Besides this fact, they are also very expensive. The system represented in this work classifies respiration and body movement with only one type of sensor and also in a non invasive way. The sensor used is a pressure sensor. This sensor is low cost and can be used for commercial proposes. The system was tested by carrying out an experiment that recorded the sleep process of a subject. These recordings showed the potential for classification of breathing rate and body movements. Although previous researches show the use of pressure sensors in recognizing posture and breathing, they have been mostly used by positioning the sensors between the mattress and bedsheet. This project however, shows an innovative way to position the sensors under the mattress.
Multilevel-cell (MLC) flash is commonly deployed in today’s high density NAND memories, but low latency and high reliability requirements make it barely used in automotive embedded flash applications. This paper presents a time domain voltage sensing scheme that applies a dynamic voltage ramp at the cells’ control gate (CG) in order to achieve fast and reliable sensing suitable for automotive applications.
This work presents a spiral antenna array, which can be used in the V- and W-Band. An array equipped with Dolph-Chebychev coefficients is investigated to address issues related to the low gain and side lobe level of the radiating structure. The challenges encountered in this achievement are to provide an antenna that is not only good matched but also presents an appreciable effective bandwidth at the frequency bands of interest. Its radiation properties including the effective bandwidth and the gain are analyzed for the W-Band.
Modern power semiconductor devices have low capacitances and can therefore achieve very fast switching transients under hard-switching conditions. However, these transients are often limited by parasitic elements, especially by the source inductance and the parasitic capacitances of the power semiconductor. These limitations cannot be compensated by conventional gate drivers. To overcome this, a novel gate driver approach for power semiconductors was developed. It uses a transformer which accelerates the switching by transferring energy from the source path to the gate path.
Experimental results of the novel gate driver approach show a turn-on energy reduction of 78% (from 80 μJ down to 17 μJ) with a drain-source voltage of 500V and a drain current of 60 A. Furthermore, the efficiency improvement is demonstrated for a hard-switching boost converter. For a switching frequency of 750 kHz with an input voltage of 230V and an output voltage of 400V, it was possible to extend the output power range by 35%(from 2.3kW to 3.1 kW), due to the reduction of the turn-on losses, therefore lowering the junction temperature of the GaN-HEMT.
A novel configuration of the dual active bridge (DAB) DC/DC converter is presented, enabling more efficient wide voltage range conversion at light loads. A third phase leg as well as a center tapped transformer are introduced to one side of the converter. This concept provides two different turn ratios, thus extending the zero voltage switching operation resulting in higher efficiency. A laboratory prototype was built converting an input voltage of 40V to an output voltage in the range of 350V to 650V. Measurements show a significant increase up to 20% in the efficiency for light-load operation.
This paper introduces a novel placement methodology for a common-centroid (CC) pattern generator. It can be applied to various integrated circuit (IC) elements, such as transistors, capacitors, diodes, and resistors. The proposed method consists of a constructive algorithm which generates an initial, close to the optimum, solution, and an iterative algorithm which is used subsequently, if the output of constructive algorithm does not satisfy the desired criteria. The outcome of this work is an automatic CC placement algorithm for IC element arrays. Additionally, the paper presents a method for the CC arrangement evaluation. It allows for evaluating the quality of an array, and a comparison of different placement methods.
A new method for the analysis of movement dependent parasitics in full custom designed MEMS sensors
(2017)
Due to the lack of sophisticated microelectromechanical systems (MEMS) component libraries, highly optimized MEMS sensors are currently designed using a polygon driven design flow. The strength of this design flow is the accurate mechanical simulation of the polygons by finite element (FE) modal analysis. The result of the FE-modal analysis is included in the system model together with the data of the (mechanical) static electrostatic analysis. However, the system model lacks the dynamic parasitic electrostatic effects, arising from the electric coupling between the wiring and the moving structures. In order to include these effects in the system model, we present a method which enables the quasi dynamic parasitic extraction with respect to in-plane movements of the sensor structures. The method is embedded in the polygon driven MEMS design flow using standard EDA tools. In order to take the influences of the fabrication process into account, such as etching process variations, the method combines the FE-modal analysis and the fabrication process simulation data. This enables the analysis of dynamic changing electrostatic parasitic effects with respect to movements of the mechanical structures. Additionally, the result can be included into the system model allowing the simulation of positive feedback of the electrostatic parasitic effects to the mechanical structures.
We present a new methodology for automatic selection and sizing of analog circuits demonstrated on the OTA circuit class. The methodology consists of two steps: a generic topology selection method supported by a “part-sizing” process and subsequent final sizing. The circuit topologies provided by a reuse library are classified in a topology tree. The appropriate topology is selected by traversing the topology tree starting at the root node. The decision at each node is gained from the result of the part-sizing, which is in fact a node-specific set of simulations. The final sizing is a simulation-based optimization. We significantly reduce the overall simulation effort compared to a classical simulation-based optimization by combining the topology selection with the part-sizing process in the selection loop. The result is an interactive user friendly system, which eases the analog designer’s work significantly when compared to typical industrial practice in analog circuit design. The topology selection method and sizing process are implemented as a tool into a typical analog design environment. The design productivity improvement achievable by our method is shown by a comparison to other design automation approaches.
This work presents a fully integrated GaN gate driver in a 180nm HV BCD technology that utilizes high-voltage energy storing (HVES) in an on-chip resonant LC tank, without the need of any external capacitor. It delivers up to 11nC gate charge at a 5V GaN gate, which exceeds prior art by a factor of 45-83, supporting a broad range of GaN transistor types. The stacked LC tank covers an area of only 1.44mm², which corresponds to a superior value of 7.6nC/mm².
A gate driver approach is presented for the reduction of turn-on losses in hard switching applications. A significant turn-on loss reduction of up to 55% has been observed for SiCMOSFETs. The gate driver approach uses a transformer which couples energy from the power path back into the gate path during switching events, providing increased gate driver current and thereby faster switching speed.
The gate driver approach was tested on a boost converter running at a switching frequency up to 300 kHz. With an input voltage of 300V and an output voltage of 600V, it was possible to reduce the converter losses by 8% at full load. Moreover, the output power range could be extended by 23% (from 2.75kW to 3.4 kW) due to the reduction of the turn-on losses.
How to protect the skin from getting sun burnt? The sun can damage your skin e.g. skin cancer. But the sun has a positive effect to the human. The time in sun and the intensity are key values between enjoy the sunbath and having a negative effect to the skin. A smart device like a UV flower could help you to enjoy the sunbath. It measures the UV index around you and gives this information to a smartphone app. The development steps of such a device are described in this paper. The UV flower is made of textile fabrics.
A 3D face modelling approach for pose-invariant face recognition in a human-robot environment
(2017)
Face analysis techniques have become a crucial component of human-machine interaction in the fields of assistive and humanoid robotics. However, the variations in head-pose that arise naturally in these environments are still a great challenge. In this paper, we present a real-time capable 3D face modelling framework for 2D in-the-wild images that is applicable for robotics. The fitting of the 3D Morphable Model is based exclusively on automatically detected landmarks. After fitting, the face can be corrected in pose and transformed back to a frontal 2D representation that is more suitable for face recognition. We conduct face recognition experiments with non-frontal images from the MUCT database and uncontrolled, in the wild images from the PaSC database, the most challenging face recognition database to date, showing an improved performance. Finally, we present our SCITOS G5 robot system, which incorporates our framework as a means of image pre-processing for face analysis.
The presented wide-Vin step-down converter introduces a parallel-resonant converter (PRC), comprising an integrated 5-bit capacitor array and a 300 nH resonant coil, placed in parallel to a conventional buck converter. Unlike conventional resonant concepts, the implemented soft-switching control eliminates input voltage dependent losses over a wide operating range. This ensures high efficiency across a wide range of Vin= 12-48V, 100-500mA load and 5V output at up to 15MHz switching frequency. The peak efficiency of the converter is 76.3 %. Thanks to the low output current ripple, the output capacitor can be as small as 50 nF, while the inductor tolerates a larger ESR, resulting in small component size. The proposed PRC architecture is also suitable for future power electronics applications using fast-switching GaN devices.
More and more power electronics applications utilize GaN transistors as they enable higher switching frequencies in comparison to conventional Si devices. Faster switching shrinks down the size of passives and enables compact solutions in applications like renewable energy, electrical cars and home appliances. GaN transistors benefit from ~10× smaller gate charge QG and gate drive voltages in the range of typically 5V vs. ~15V for Si.
Software and system development is complex and diverse, and a multitude of development approaches is used and combined with each other to address the manifold challenges companies face today. To study the current state of the practice and to build a sound understanding about the utility of different development approaches and their application to modern software system development, in 2016, we launched the HELENA initiative. This paper introduces the 2nd HELENA workshop and provides an overview of the current project state. In the workshop, six teams present initial findings from their regions, impulse talk are given, and further steps of the HELENA roadmap are discussed.
Modern power transistors are able to switch at very high transition speed, which can cause EMC violations and overshoot. This is addressed by a gate driver with variable gate current, which is able to control the transition speed. The key idea is that the gate driver can influence the di/dt and dv/dt transition separately and optimize whichever transition promises the highest improvement while keeping switching losses low. To account for changes in the load current, supply voltage, etc., a control loop is required in the driver to ensure optimized switching. In this paper, an efficient control scheme for an automotive gate driver with variable output current capability is presented. The effectiveness of the control loop is demonstrated for a MOSFET bridge consisting of OptiMOS-T2™devices with a total gate charge of 39nC. This bridge setup shows dv/dt transitions between 50 to 1000ns, depending on driving current. The driver is able to switch between gate current levels of 1 to 500mA in 10/15ns (rising/falling transition). With the implemented control loop the driver is measured to significantly reduce the ringing and thereby reduce device stress and electromagnetic emissions while keeping switching losses 52% lower than with a constant current driver.
Real estate markets are known to fluctuate. The real estate market in Stuttgart, Germany, has been booming for more than a decade: square-meter price hit top levels and real estate agents claim that market prices will continue to increase. In this paper, we test this market understanding by developing and analyzing a system dynamics model that depicts the Stuttgart real estate market. Simulating the model explains oscillating behavior arising from significant time delays and endogenous feedback structures – and not necessarily oscillating interest rates, as market experts assume. Scenarios provide insights into the system's behavior reacting to changes exogenous to the model. The first scenario tests the market development under increasing interest rates. The other scenario deals with possible effects on the real estate market if the regional automotive economy suffers from intense competition with new market players entering with alternative fuel vehicles and new technologies. With a policy run we test market structure changes to eliminate cyclical effects. The paper confirms that the business cycle in the Stuttgart real estate market arises from within the system's underlying structure, thus emphasizing the importance of understanding feedback structures.