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§ 28e Abs. 1 Satz 2 SGB IV – Lehrstück für den Gesetzgeber oder: Wie eine Norm sich selbst erledigt!
(2015)
The paper presents a new control strategy of management of transport companies operating in completive transport environment. It is aimed to optimise the headway of transport companies to provide the balance between costs and benefits of operation under competition. The model of transport system build using AnyLogic comprises agent-based and discrete-event techniques. The model combined two transport companies was investigated under condition of the competition between them. It was demonstrated that the control strategy can ensure the balance of interests of transport companies trying to find compromise between cost of operation and quality of service.
Work in progress: Starter-project for first semester students to survey their engineering studies
(2015)
In education, finding the appropriate learning pace that fits to the members of a large group is a challenging task. This becomes especially evident when teaching multidisciplinary subjects such as epidemiology in medicine or computer science in most study programs, since lecturers have to face a very heterogeneous state of previous knowledge. Approaching this issue requires an individual supervision of each and every student, which is obviously bounded by the available resources. Moreover, when referring back to the second example, writing computer programs requires a complex installation and configuration of development tools. Many beginning programmers already become stuck at this entry stage. This paper introduces WHELP, a Web-based Holistic E-Learning Platform, which provides an integrated environment enabling the learning and teaching of computer science topics without the need to install any software. Moreover, WHELP includes an interactive feedback system for each programming exercise, where lecturers or tutors can supply comments, improvements, code assistance or tips helping the students to accomplish their tasks. Furthermore, WHELP offers a statistical analysis module as well as a real-time classroom polling system both promoting an overview of the state of knowledge of a course. In addition to that, WHELP enables collaborative working including code-sharing and peer-to-peer learning. This feature enables students to work on exercises simultaneously at distinct places. WHELP has been successfully deployed in the winter term 2013 at the Cologne University of Applied Sciences supporting the 120 students and 3 lecturers to learn and teach basic topics of computer science in an engineering study program.
Weniger Gutachten
(2015)
Dieses Buch führt Sie umfassend in die WebSocket-Technik und die damit einhergehenden neuen Entwicklungsmöglichkeiten ein. Unter den zahlreichen exemplarischen Anwendungen finden sich Beispiele auf Basis von Node.js, Vert.x, und JSR 356, als Programmiersprachen werden Java und JavaScript eingesetzt.
WebSocket - WS^2 2.0
(2015)
Das Websocket-Protokoll hat sich derzeit zu einer wichtigen Technologie für die Entwicklung moderner Webanwendungen durchgesetzt. Mit der Möglichkeit eine dauerhafte bidirektionale Verbindung zwischen Client und Server aufzubauen, ergeben sich neue Anwendungsszenarien, die vorher mit dem reinen HTTP nicht realisierbar waren. Die Einsatzgebiete reichen hier von einfachen Chats bis hin zu komplexen Systemen wie das kollaborative Arbeiten an Dokumenten in Echtzeit. Mittlerweile hat sogar der Instant Messaging-Dienst WhatsApp die Vorteile der WebSocket-Technologie für sich entdeckt und erlaubt Benutzern ihre Nachrichten nun auch über den Webbrowser auszutauschen.
Dieser Workshop soll den Teilnehmern zeigen wie sie die oben genannten oder andere Echzeitwebanwendungen mit der WebSocket-Technologie implementieren können. Nach einer kurzen Einführung wird gezeigt wie es in einfachen Schritten möglich ist, mehr als nur simple Chat-Anwendungen mit den WebSocket-Protokoll zu realisieren. Zudem stellt der Workshop nach Möglichkeit auch die Verwendung von Subprotokollen vor, wodurch auch RPC- sowie Publish and Subscribe-Anwendungen mit WebSockets umgesetzt werden können.
Web of Services Security
(2015)
Dieser Tagungsband enthält die Beiträge zum 12. Workshop zum Thema Virtuelle und Erweiterte Realität der Fachgruppe VR/AR der Gesellschaft für Informatik e.V. Der Workshop dient zum Informations- und Ideenaustausch deutschsprachigen WissenschaftlerInnen, zusätzlich bietet der Workshop den idealen Rahmen aktuelle Ergebnisse und Vorhaben aus Forschung und Entwicklung einem fachkundigen Publikum zur Diskussion zu stellen. Insbesondere wollen wir auch jungen Nachwuchswissenschaftlern die Möglichkeit geben, ihre Arbeiten zu präsentieren.
Der Nutzen von Prozessmanagement für die Effizienz und Effektivität der Organisation von Unternehmen ist vielfach bestätigt. Eine Studie der gfo-Gesellschaft für Organisation stellt fest, dass der Umsetzungsgrad der Prozessorganisation in Unternehmen dennoch mangelhaft ist. Es fehlt die Unterstützung der Leitung, die selbst noch überwiegend funktional organisiert ist.
In this paper, a set of micro-benchmarks is proposed to determine basic performance parameters of single-node mainstream hardware architectures for High Performance Computing. Performance parameters of recent processors, including those of accelerators, are determined. The investigated systems are Intel server processor architectures as well as the two accelerator lines Intel Xeon Phi and Nvidia graphic processors. Results show similarities for some parameters between all architectures, but significant differences for others.
This paper gives necessary foundations to understand the mechanism of warning processing and summarizes the state of the art in warning development. That includes a description of tools, researchers use to work in this scientific field. In detail these are models that describes the human way of processing warnings and mental models. Both are presented detailed with relevant examples. The paper tells how these tools are connected and how they are used to improve the effectiveness of warnings.
The study of locomotion in virtual environments is a diverse and rewarding research area. Yet, creating effective and intuitive locomotion techniques is challenging, especially when users cannot move around freely. While using handheld input devices for navigation may often be good enough, it does not match our natural experience of motion in the real world. Frequently, there are strong arguments for supporting body-centered self-motion cues as they may improve orientation and spatial judgments, and reduce motion sickness. Yet, how these cues can be introduced while the user is not moving around physically is not well understood. Actuated solutions such as motion platforms can be an option, but they are expensive and difficult to maintain. Alternatively, within this article we focus on the effect of upper-body tilt while users are seated, as previous work has indicated positive effects on self-motion perception. We report on two studies that investigated the effects of static and dynamic upper body leaning on perceived distances traveled and self-motion perception (vection). Static leaning (i.e., keeping a constant forward torso inclination) had a positive effect on self-motion, while dynamic torso leaning showed mixed results. We discuss these results and identify further steps necessary to design improved embodied locomotion control techniques that do not require actuated motion platforms.
Aktuelle Studien prognostizieren bis zum Jahr 2018 etwa 27.000 Nachfolgen in deutschen Familienunternehmen pro Jahr. Dieses Buch unterstützt Sie bei der Herausforderung Unternehmensnachfolge in allen wichtigen betriebswirtschaftlichen, rechtlichen, organisatorischen, steuerlichen und psychologischen Fragen und bei der Umsetzung Ihrer individuellen Nachfolgestrategie.
Unternehmensführung
(2015)
Dieses Buch führt Sie systematisch und leicht verständlich in das Thema Unternehmensführung ein. Es konzentriert sich bewusst auf die wichtigsten Fragen des Handelns als verantwortlicher Manager in der Unternehmensführung bzw. in der Bereichs- oder Abteilungsverantwortung. Dabei werden ausgewählte Probleme aus dem Management entwickelt und anschließend anhand von Praxisbeispielen erläutert. (Verlagsangaben)
Understanding the Internet of Things: A Conceptualisation of Business-to-Thing (B2T) Interactions
(2015)
Ultra-fast photopolymerization of experimental composites: DEA and FT-NIRS measurement comparison
(2015)
Despite the lack of standardisation for building REST-ful HTTP applications, the deployment of REST-based Web Services has attracted an increased interest. This gap causes, however, an ambiguous interpretation of REST and induces the design and implementation of REST-based systems following proprietary approaches instead of clear and agreed upon definitions. Issues arising from these shortcomings have an influence on service properties such as the loose coupling of REST-based services via a unitary service contract and the automatic generation of code. To overcome such limitations, at least two prerequisites are required: the availability of specifications for implementing REST-based services and auxiliaries for auditing the compliance of those services with such specifications. This paper introduces an approach for conformance testing of REST-based Web Services. This appears conflicting at the first glance, since there are no specifications available for implementing REST by, e.g., t he prevalent technology set HTTP/URI to test against. Still, by providing a conformance test tool and leaning it on the current practice, the exploration of service properties is enabled. Moreover, the real demand for standardisation gets explorable by such an approach. First investigations conducted with the developed conformance test system targeting major Cloud-based storage services expose inconsistencies in many respects which emphasizes the necessity for further research and standardisation.
Formal concept analysis (FCA) as introduced in [4] deals with contexts and concepts. Roughly speaking, a context is an environment that is equipped with some kind of "knowledge". Such contexts are also known as information or knowledge representation systems where the knowledge consists of (intensional) descriptions relating sets of objects to sets of properties. Given extsensional and intensional descriptions (the latter one in terms of binary attributes), they can be arranged in a taxonomy or concept lattice.
The Whole Is More than the Sum of Its Parts - On Culture in Education and Educational Culture
(2015)
The Learning Culture Survey investigates learners’ expectations towards and perceptions of education on international level with the aim to make culture in the context of education better understandable and support educators to prevent and solve intercultural conflicts in education. So far, we found that culture-related expectations differ between educational settings, depend on the age of the learners, and that a nationally homogenous educational culture is rather an exception than the rule. The results of our recently completed longitudinal study provided evidence that educational culture on the institutional level actually is persistent, at least over a term of four years. After a brief introduction of the general background, we will subsume the steps taken during the past seven years and achieved general insights regarding educational culture. Last, we will introduce a method for the determination of conflict potential, which bases on the understanding of culture as the level to w hich people within a society accept deviations from the usual. We close with demonstrating the method’s functionality on examples from the Learning Culture Survey.
The human MPV17-related mitochondrial DNA depletion syndrome is an inherited autosomal recessive disease caused by mutations in the inner mitochondrial membrane protein MPV17. Although more than 30 MPV17 gene mutations were shown to be associated with mitochondrial DNA depletion syndrome, the function of MPV17 is still unknown. Mice deficient in Mpv17 show signs of premature aging. In the present study, we used electrophysiological measurements with recombinant MPV17 to reveal that this protein forms a non-selective channel with a pore diameter of 1.8 nm and located the channel's selectivity filter. The channel was weakly cation-selective and showed several subconductance states. Voltage-dependent gating of the channel was regulated by redox conditions and pH and was affected also in mutants mimicking a phosphorylated state. Likewise, the mitochondrial membrane potential (Δψm) and the cellular production of reactive oxygen species were higher in embryonic fibroblasts from Mpv17−/− mice. However, despite the elevated Δψm, the Mpv17-deficient mitochondria showed signs of accelerated fission. Together, these observations uncover the role of MPV17 as a Δψm-modulating channel that apparently contributes to mitochondrial homeostasis under different conditions.
Introduction: After cellulose, lignin represents the most abundant biopolymer on earth that accounts for up to 18-35 % by weight of lignocellulose biomass. Today, it is a by-product of the paper and pulping industry. Although lignin is available in huge amounts, mainly in form of so called black liquor produced via Kraft-pulping, processes for the valorization of lignin are still limited [1]. Due to its hyperbranched polyphenol-like structure, lignin gained increasing interest as biobased building block for polymer synthesis [2]. The present work is focused on extraction and purification of lignin from industrial black liquor and synthesis of lignin-based polyurethanes.
Simultaneous multifrequency radio observations of the Galactic Centre magnetar SGR J1745-2900
(2015)
Semantic Image Segmentation Combining Visible and Near-Infrared Channels with Depth Information
(2015)
Image understanding is a vital task in computer vision that has many applications in areas such as robotics, surveillance and the automobile industry. An important precondition for image understanding is semantic image segmentation, i.e. the correct labeling of every image pixel with its corresponding object name or class. This thesis proposes a machine learning approach for semantic image segmentation that uses images from a multi-modal camera rig. It demonstrates that semantic segmentation can be improved by combining different image types as inputs to a convolutional neural network (CNN), when compared to a single-image approach. In this work a multi-channel near-infrared (NIR) image, an RGB image and a depth map are used. The detection of people is further improved by using a skin image that indicates the presence of human skin in the scene and is computed based on NIR information. It is also shown that segmentation accuracy can be enhanced by using a class voting method based on a superpixel pre-segmentation. Models are trained for 10-class, 3-class and binary classification tasks using an original dataset. Compared to the NIR-only approach, average class accuracy is increased by 7% for 10-class, and by 22% for 3-class classification, reaching a total of 48% and 70% accuracy, respectively. The binary classification task, which focuses on the detection of people, achieves a classification accuracy of 95% and true positive rate of 66%. The report at hand describes the proposed approach and the encountered challenges and shows that a CNN can successfully learn and combine features from multi-modal image sets and use them to predict scene labeling.
Schlussbericht HIGEDIS
(2015)
Roughness by Residuals
(2015)
Rough set theory (RST) focuses on forming posets of equivalence relations to describe sets with increasing accuracy. The connection between modal logics and RST is well known and has been extensively studied in their relation algebraic (RA) formalisation. RST has also been interpreted as a variant of intuitionistic or multi-valued logics and has even been studied in the context of logic programming.
So far, sustainable HCI has mainly focused on the domestic context, but there is a growing body of work looking at the organizational context. As in the domestic context, these works still rest on psychological theories for behaviour change used for the domestic context. We supplement this view with an organizational theory-informed approach that adopts organizational roles as a key element. We will show how a role-based analysis could be applied to uncover information needs and to give em-ployee’s eco-feedback, which is linked to their tasks at hand. We illustrate the approach on a qualitative case study that was part of a broader, ongoing action research conducted in a German production company.
Binary relations with certain properties such as biorders, equivalences or difunctional relations can be represented as particular matrices. In order for these properties to be identified usually a rearrangement of rows and columns is required in order to reshape it into a recognisable normal form. Most algorithms performing these transformations are working on binary matrix representations of the underlying relations. This paper presents an approach to use the RLE-compressed matrix representation as a data structure for storing relations to test whether they are biorders in a hopefully more efficient way.
IT-accessiblity is often treated as an orphan in companies. Even though the proportion of disabled people is substantial and people become older and more susceptible to disabilities. Besides cost factors, companies often do not have a plan how to implement and control IT-accessibility successfully. However, most companies are familiar with IT-maturity frameworks to evaluate and improve their own IT-infrastructure. It would facilitate dealing with IT-accessibility, if IT-maturity frameworks consider IT-accessibility and provide recommendations and solutions for a successful implementation. Therefore, this article conducts a review of an acknowledged IT-maturity framework with regard to its capability to enable implementation of IT-accessibility in an organization. The first part of this article will illustrate the motivation and background for the authors concern with such a topic. Afterwards the authors will introduce the reader to the reviewed IT-maturity framework and provide basic knowledge on IT-accessibility. The main part of the article will deal with the review of the applied IT-maturity framework and outline examples of critical capabilities for successfully implementing IT-accessibility in an organization. The final section will derive implications and close with planned future research activities in this field.
Die Rückkehr ins Erwerbsleben (Return to Work, RTW) wird für onkologische Rehabilitanden zunehmend zum zentralen Behandlungsziel, wodurch auch die Bereitstellung spezifischer berufsorientierter Maßnahmen an Bedeutung gewinnt (z. B. Mehnert, Koch, 2012). Die Überprüfung der Behandlungsergebnisse solcher Maßnahmen stellt einen wichtigen Baustein des Qualitätsmanagements der Rehabilitationseinrichtungen dar. Im Rahmen der „Reha-QM-Outcome-Studie“ des Qualitätsverbundes Gesundheit und der Deutschen Rentenversicherung Baden-Württemberg (Nübling et al., 2014) wurde daher ein besonderes Augenmerk auf das Outcome und die RTW-Quote der onkologischen Patienten, auch im Vergleich zu anderen Hauptindikationen, gelegt.
[Context and motivation] Communication in distributed software development is usually supported by issue tracking systems. Within these systems, most of the communication is stored as unstructured natural language text. The natural language text, however, contains much information with respect to requirements management, e.g. discussion, clarification and prioritization of features, bugs, and refactorings. [Question] This paper investigates the information stored in the issue tracking systems of four different open-source projects. It categorizes the text and reports on the distribution of issue types and information types. [Principal ideas/results] A manual analysis of 80 issues, using a grounded approach, is conducted to derive a taxonomy of issue types and information types. Subsequently, the taxonomy is used as a codebook, to manually categorize and structure the text in another 120 issues. [Contribution] The first contribution of this paper is the taxonomy of issue and information types and the second contribution is an in-depth analysis of the natural language data and the communication. This analysis showed, for example, that information with respect to prioritization and scheduling can be found in natural language data, whether the ITS supports such tasks in a structured way or not.
Despite the opportunities and benefits of OER, research and practice has shown how the OER repositories have a hard time in reaching an active user-base. The opportunities of experience exchange and simple feedback mechanisms of social software have been realized for improving the situation and many are basing or transforming their OER offerings towards socially powered environments. Research on social software has shown how knowledge-sharing barriers in online environments are highly culture and context-specific and require proper investigation. It is crucial to study what challenges might arise in such environments and how to overcome them, ensuring a successful uptake. A large-scale (N = 855) cross-European investigation was initiated in the school context to determine which barriers teachers and learners perceive as critical. The study highlights barriers on cultural distance, showing how those are predicted by nationality and age of the respondents. The paper concludes with recommendations for overcoming those barriers.
In this doctoral thesis the curing process of visible light-curing (VLC) dental composites and 3D printing rapid prototyping (RP) materials are investigated with the focus on dielectric analysis (DEA). This method is able to monitor the curing of resins in an alternating electric fringe field with adjustable frequencies and is often used for cure control of composites manufacturing in the aviation and automotive industry but hardly established in dental science or RP method development. It is capable of investigating very fast initiation and primary curing processes using high frequencies in the kHz-range. The aim of the Thesis is a better understanding of the curing processes with respect to curing parameters such as resin composition, viscosity, temperature, and for light-curing composites also light intensity and irradiation depth. Due to the nature of both dental and RP systems an application of specific experimental set-up had to be designed allowing for the generation of reproducible and valid results. Subsequently, different evaluation methods were developed to characterize the curing behavior of both material types. A special focus was paid to the determination of kinetic parameters from DEA measurements. Reaction rates of the curing of the corresponding thermosets were calculated and applied to the ion viscosity curves measured by DEA to evaluate reaction kinetic parameters. For the dental composites it could be clearly shown that the initial curing rate is directly proportional to light intensity and not to its square root as proposed by many others authors. A good description of the curing behaviour of 3DP RP materials was also achieved assuming a reaction order smaller than one. This data provides the base for the kinetic modeling of polymerization and curing processes proposed within the Thesis.
Qualitätssicherung von Weiterbildungsmaßnahmen der Bundesagentur für Arbeit von 1969 bis heute
(2015)
Quality Management in Education: Business Process Modelling in Interdisciplinary Environments
(2015)
Lignin ist bereits ein intensives Gebiet der Forschung, allerdings werden Verknüpfungen zwischen Quelle, Aufschlussmethode und Einsatz in der Literatur kaum beschrieben. In der vorliegenden Arbeit werden Lignine von verschiedenen Quellen (Weizenstroh, Buche, Nadelholz) und Aufschlussmethoden (AFEX, Wasserdampfaufschluss, Organosolv, Saure Hydrolyse) analytisch erfasst und hinsichtlich ihres Einsatzes in polymeren Materialien charakterisiert. Eine breite Auswahl an Methoden wurden eingesetzt, FT-IR- Spektroskopie, UV-Vis, 31P-NMR, GPC, Pyrolyse-GC/MS, sowie HPLC zur Bestimmung der Reinheit gemäß des NREL-Standard-Protokolls. Thermische Analysen, wie TGA und DSC zeigten Glasübergangstemperaturen um 120°C, sowie Zersetzungstemperaturen zwischen 340°C und 380°C. Die Ergebnisse weisen für das Organosolv-Buchenholz-Lignin hochreine Fraktionen auf, die bis dato noch nicht erreicht wurden. Die Ergebnisse dieser Arbeit identifizien die Organosolv-Buchenholz-Lignine als ein verwertbares Produkt im Hinblick auf die Anwendung in Polyurethanen sowie Phenol-Formaldehydharzen.
Secure vehicular communication has been discussed over a long period of time. Now,- this technology is implemented in different Intelligent Transportation System (ITS) projects in europe. In most of these projects a suitable Public Key Infrastructure (PKI) for a secure communication between involved entities in a Vehicular Ad hoc Network (VANET) is needed. A first proposal for a PKI architecture for Intelligent Vehicular Systems (IVS PKI) is given by the car2car communication consortium. This architecture however mainly deals with inter vehicular communication and is less focused on the needs of Road Side Units. Here, we propose a multi-domain PKI architecture for Intelligent Transportation Systems, which considers the necessities of road infrastructure authorities and vehicle manufacturers, today. The PKI domains are cryptographically linked based on local trust lists. In addition, a crypto agility concept is suggested, which takes adaptation of key length and cryptographic algorithms during PKI operation into account.
Die psychische Komorbidität bei chronisch körperlichen Erkrankungen gilt als weitgehend belegt. Je nach Indikationsbereich variiert der Anteil zusätzlich psychisch erkrankter Patienten zwischen 16 und 24 % (4-Wochen-Prävalenz) bzw. zwischen 29 und 41 % (1-Jahres- Prävalenz; Härter et al., 2007). Aktuelle Konzepte legen eine stärkere Fokussierung auf psychosoziale, vor allem psychologische, psychotherapeutische und pädagogische Behandlungsbausteine innerhalb der stationären Rehabilitation nahe (Bengel et al., 2014; Seiter et al., 2012). Zusätzlich werden gezielte Nachsorgekonzepte entwickelt und erprobt (z. B. Deck, Hüppe, 2014). Der vorliegende Beitrag geht auf der Grundlage einer aktuellen Versichertenstichprobe der Frage nach, wie psychische Beeinträchtigung, Behandlungsempfehlung und nachfolgende Inanspruchnahme ambulanter psychotherapeutischer Leistungen zusammenhängen und mit welchen Behandlungsergebnissen sie assoziiert sind.
Unternehmen agieren in einem dynamischen Umfeld mit hoher Komplexität und Unsicherheit. Um dabei langfristig wettbewerbsfähig zu bleiben, ist eine kontinuierliche Optimierung der Prozesse erforderlich. Eine konsequente Prozessorientierung wird daher seit langem angestrebt. Zur Ermittlung des aktuellen Standes der Prozessorganisation in deutschen Unternehmen hat die Gesellschaft für Organisation e. V. (gfo) eine Studie durchführen lassen, deren erste Ergebnisse hier vorgestellt werden.