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Trotz einer sauber aufgesetzten Projektplanung und der konsequenten Einhaltung der vorgeschriebenen PM-Methodik verfehlen Projekte oft ihre Zielvorgaben. Einer der wichtigsten Gründe hierfür ist die stark gestiegene Komplexität. Diese erfordert eine neue Sichtweise auf das Projektmanagement, wie Olaf Ihlow in seinem Trend-Beitrag meint.
Auch eine hervorragende Geschäftsidee braucht Zeit, bis sie von potenziellen Kunden bemerkt und honoriert wird. Trotz guter Planung und engagierter Kundenakquisition kann das Auftragsvolumen, auch aufgrund konjunktureller Schwächen, hinter den Erwartungen zurückbleiben. Zudem können sich Schwierigkeiten in der Produktentwicklung, in der Leistungserstellung und in der Auftragsabwicklung einstellen.
We are happy to present you the special issue on Best Practice in Robot Software Development of the Journal on Software Engineering for Robotics! The spark for this special issue came during the eighth workshop on Software Development and Integration in Robotics (SDIR) at the 2013 IEEE International Conference on Robotics and Automation. The workshop focused on Robot Software Architectures, and the fruitful discussions made it clear that the design, development, and deployment of robot software is always an interplay between competing aspects. These are often couched in antagonistic pairs, such as dependability versus performance, and prominently include quality attributes as well as functional, nonfunctional, and application requirements.
Ziel des hier beschriebenen Forschungsprojekts war die Entwicklung eines prototypischen Fahrradfahrsimulators für den Einsatz in der Verkehrserziehung und im Verkehrssicherheitstraining. Der entwickelte Prototyp soll möglichst universell für verschiedene Altersklassen und Applikationen einsetzbar sowie mobil sein.
The objective of this research project is to develop a user-friendly and cost-effective interactive input device that allows intuitive and efficient manipulation of 3D objects (6 DoF) in virtual reality (VR) visualization environments with flat projections walls. During this project, it was planned to develop an extended version of a laser pointer with multiple laser beams arranged in specific patterns. Using stationary cameras observing projections of these patterns from behind the screens, it is planned to develop an algorithm for reconstruction of the emitter’s absolute position and orientation in space. Laser pointer concept is an intuitive way of interaction that would provide user with a familiar, mobile and efficient navigation though a 3D environment. In order to navigate in a 3D world, it is required to know the absolute position (x, y and z position) and orientation (roll, pitch and yaw angles) of the device, a total of 6 degrees of freedom (DoF). Ordinary laser-based pointers when captured on a flat surface with a video camera system and then processed, will only provide x and y coordinates effectively reducing available input to 2 DoF only. In order to overcome this problem, an additional set of multiple (invisible) laser pointers should be used in the pointing device. These laser pointers should be arranged in a way that the projection of their rays will form one fixed dot pattern when intersected with the flat surface of projection screens. Images of such a pattern will be captured via a real-time camera-based system and then processed using mathematical re-projection algorithms. This would allow the reconstruction of the full absolute 3D pose (6 DoF) of the input device. Additionally, multi-user or collaborative work should be supported by the system, would allow several users to interact with a virtual environment at the same time. Possibilities to port processing algorithms into embedded processors or FPGAs will be investigated during this project as well.
The work being described in this paper is the result of a cooperation project between the Institute of Visual Computing at the Bonn-Rhein-Sieg University of Applied Sciences, Germany and the Laboratory of Biomedical Engineering at the Federal University of Uberlândia, Brazil. The aim of the project is the development of a virtual environment based training simulator which enables for better and faster learning the control of upper limb prostheses. The focus of the paper is the description of the technical setup since learning tutorials still need to be developed as well as a comprehensive evaluation still needs to be carried out.
Perception is one of the most important cognitive capabilities of an entity since it determines how an entity perceives its environment. The presented work focuses on providing cost efficient but realistic perceptual processes for intelligent virtual agents (IVAs) or NPCs with the goal of providing a sound information basis for the entities' decision making processes. In addition, an agent-central perception process should rovide a common interface for developers to retrieve data from the IVAs' environment. The overall process is evaluated by applying it to a scenario demonstrating its benefits. The evaluation indicates, that such a realistically simulated perception process provides a powerful instrument to enhance the (perceived) realism of an IVA's simulated behavior.
Might the gravity levels found on other planets and on the moon be sufficient to provide an adequate perception of upright for astronauts? Can the amount of gravity required be predicted from the physiological threshold for linear acceleration? The perception of upright is determined not only by gravity but also visual information when available and assumptions about the orientation of the body. Here, we used a human centrifuge to simulate gravity levels from zero to earth gravity along the long-axis of the body and measured observers' perception of upright using the Oriented Character Recognition Test (OCHART) with and without visual cues arranged to indicate a direction of gravity that differed from the body's long axis. This procedure allowed us to assess the relative contribution of the added gravity in determining the perceptual upright. Control experiments off the centrifuge allowed us to measure the relative contributions of normal gravity, vision, and body orientation for each participant. We found that the influence of 1 g in determining the perceptual upright did not depend on whether the acceleration was created by lying on the centrifuge or by normal gravity. The 50% threshold for centrifuge-simulated gravity's ability to influence the perceptual upright was at around 0.15 g, close to the level of moon gravity but much higher than the threshold for detecting linear acceleration along the long axis of the body. This observation may partially explain the instability of moonwalkers but is good news for future missions to Mars.
The perceived direction of “up” is determined by gravity, visual information, and an internal estimate of body orientation (Mittelstaedt, 1983; Dyde et al., 2006). Is the gravity level found on other worlds sufficient to maintain gravity’s contribution to this perception? Difficulties in stability reported anecdotally by astronauts on the lunar surface (NASA 1972) suggest that the moon’s gravity may not be, despite this value being far above the threshold for detecting linear acceleration. Knowing how much gravity is needed to provide a reliable orientation cue is required for training and preparing astronauts for future missions to the moon, mars and beyond.
The case for basic human needs in coaching: A neuroscientific perspective - The SCOAP Coach Theory
(2014)
SOA-Readiness of REST
(2014)
Service Security Revisited
(2014)
Das AD 2000-Regelwerk ist der dominierende Standard für den Druckbehälterbau in Deutschland. Die bereits in anderen europäischen Ländern verbreitete DIN EN 13445 findet kaum Berücksichtigung. Dies allerdings zu Unrecht, denn ein aktueller Vergleich, der im Rahmen einer Bachelorarbeit durchgeführte wurde, zeigt: Die EN 13445 ist zu einer echten Alternative gereift. Gerade das Hauptargument gegen eine Umstellung, die steigenden Kosten, ist längst überholt.
Masterkurs IT-Controlling
(2014)
Unternehmen nutzen teilweise veraltete Betriebssystem-Software, die nicht mehr gewartet werden. Beispiele sind "Windows XP" oder ab 14.05.2015 "Windows Server 2003" der Firma Microsoft. Das Paper analysiert die Situation im Hinblick auf signifikante Risiken wie z.B. die mögliche Versagung von Jahresabschlusstestaten und schlägt Maßnahmen für das Management vor.
In general, mathematics plays a central role in our lives because today mathematics regulates our everyday life with techniques, technologies and procedures, for example coding techniques for credit cards or the drafting of curves and surfaces for construction procedures [5]. Obviously, mathematics continues to be an important element of engineering education and it still represents a major obstacle for the students. Lacking the knowledge of several topics, changing learning behavior and inadequate overall conditions at universities for the repetition of school mathematics were mentioned to be causes for the constantly increasing gap between the initial level of mathematics at university and the prior knowledge of the first semester students [2].
Hydrogen sulfide (H2S) is well known as a highly toxic environmental chemical threat. Prolonged exposure to H2S can lead to the formation of pulmonary edema. However, the mechanisms of how H2S facilitates edema formation are poorly understood. Since edema formation can be enhanced by an impaired clearance of electrolytes and, consequently, fluid across the alveolar epithelium, it was questioned whether H2S may interfere with transepithelial electrolyte absorption. Electrolyte absorption was electrophysiologically measured across native distal lung preparations (Xenopus laevis) in Ussing chambers. The exposure of lung epithelia to H2S decreased net transepithelial electrolyte absorption. This was due to an impairment of amiloride-sensitive sodium transport. H2S inhibited the activity of the Na+/K+-ATPase as well as lidocaine-sensitive potassium channels located in the basolateral membrane of the epithelium. Inhibition of these transport molecules diminishes the electrochemical gradient which is necessary for transepithelial sodium absorption. Since sodium absorption osmotically facilitates alveolar fluid clearance, interference of H2S with the epithelial transport machinery provides a mechanism which enhances edema formation in H2S-exposed lungs.
We consider the Hopfield model with n neurons and an increasing number p=p(n) of randomly chosen patterns and use Stein's method to obtain rates of convergence for the central limit theorem of overlap parameters, which holds for every fixed choice of the overlap parameter for almost all realisations of the random patterns.
Der Beitrag beschreibt die Einführung eines prozessorientierten Qualitätsmanagementsystems (QM-System) an der Hochschule Bonn-Rhein-Sieg. Diese wurde 1995 gegründet und hat derzeit rund 6500 Studierende an drei Standorten: Sankt Augustin, Rheinbach und Hennef. Hier lehren und forschen rund 140 engagierte Professorinnen und Professoren, unterstützt durch über 300 Mitarbeiterinnen und Mitarbeiter und ebenso viele Lehrbeauftragte aus Wirtschaft, Politik und Wissenschaft. Angesichts der Verteilung über mehrere Standorte mit unterschiedlichen fachlichen Schwerpunkt- und Zielsetzungen wird der Aufbau eines gemeinsamen QM zugleich als Organisationsentwicklungsprozess gestaltet. Strategische Basis dafür ist der Hochschulentwicklungsplan. Begonnen wurde Ende 2009 mit der Erstellung einer Feasibility-Studie, um die zukünftige Rolle von QM an der Hochschule zu untersuchen und einen gangbaren Weg für die Integration in die Hochschulentwicklung zu beschreiben. Der folgende Bericht gibt einen Überblick über die daraus entstandenen Aktivitäten sowie einen Eindruck von den damit verbundenen Chancen und Schwierigkeiten. Einer der größten Erfolge besteht bislang in der Anerkennung von QM als Daueraufgabe der Hochschule und ihrer Mitglieder. Herausfordernd ist, diesen Anspruch im Hochschulalltag umzusetzen.
The RoCKIn@Work Challenge
(2014)
Simulation of thermal behavior during friction stir welding process for predicting residual stresses
(2014)
Der Begriff der Nachhaltigkeit ist heute weit verbreitet, und seine Nutzung erstreckt sich auf alle Gesellschaftsbereiche. Als abstraktes Leitprinzip bleibt oftmals unklar, wie der Begriff definiert und ausgelegt wird. Seine Unbestimmtheit trägt zur Verwässerung und inflationären Verwendung bei. Erschwerend wirkt zusätzlich die unzureichende Trennung des politischen vom alltagssprachlichen Begriff der Nachhaltigkeit.
In diesem Paper wird das abbildende Millimeterwellen-Radarsystem SAMMI® (Stand Alone MilliMeter wave Imager) des Fraunhofer-Institutes für Hochfrequenzphysik und Radartechnik FHR vorgestellt. SAMMI ist ein CW System welches bei einer Messfrequenz von 78 GHz die Proben in Transmission vermisst. Durch ein Endlosband wird ein kontinuierlicher Materialstrom sichergestellt, wobei ein DIN A4 Blatt innerhalb von 20 s durchleuchtet wird. SAMMI besitzt die Größe eines durchschnittlichen Laserdruckers wodurch es leicht zu transportieren und in wenigen Minuten einsatzbereit ist. Die mittels SAMMI erfassten Messdaten, können bereits während der Datenerfassung mit verschiedenen bereits vorinstallierten Verfahren aufbereitet und analysiert werden. Zu den integrierten Algorithmen in SAMMI® gehören unter anderen Verfahren zum 2D-Phase Unwrapping-, Cluster- und Rekonstruktions-Algorithmen zur Berechnung der Materialparameter. Die offene Softwareschnittstelle erlaubt auch die Implementierung eigener Verfahren auf der mitgelieferten Computer-Hardware. Mit den integrierten Algorithmen bietet SAMMI® eine Vielzahl an Möglichkeiten um z.B. Verunreinigungen in Materialien zu detektieren oder Schwankungen im Fertigungsprozess frühzeitig zu identifizieren. Desweiteren ist SAMMI® eine optimale Ausbildungsplattform in den Bereichen der industriellen Bildverarbeitung mittels Hochfrequenzsensoren. Insbesondere können Verfahren für unterschiedliche Anwendungen getestet bzw. für Anwendungen weiterentwickelt werden. Es werden konkrete Beispiele aus dem Bereich der Qualitätssicherung erläutert und Möglichkeiten des Gerätes und der Millimeterwellen-Technologie für die zerstörungsfreie Prüfung in Detail beschrieben.
An Universitäten und Fachhochschulen ist die Mathematik-Ausbildung eines der Nadelöhre für angehende Ingenieurinnen und Ingenieure. Viele Studierende der Ingenieurwissenschaften scheitern in den ersten Studiensemestern an den Anforderungen der Mathematik. Lehrende, Fach- und Hochschuldidaktiker/innen und zunehmend auch Fachvertretungen und Verbände stellen sich die Frage, was an den Fakultäten und Fachbereichen getan werden kann, damit Studierende ihre mathematischen Fähigkeiten vergrößern und den anspruchsvollen Studienweg zur Ingenieurin oder zum Ingenieur meistern können.
It has become increasingly clear that caspases, far from being merely cell death effectors, have a much wider range of functions within the cell. These functions are as diverse as signal transduction and cytoskeletal remodeling, and caspases are now known to have an essential role in cell proliferation, migration, and differentiation. There is also evidence that apoptotic cells themselves can direct the behavior of nearby cells through the caspase-dependent secretion of paracrine signaling factors. In some processes, including the differentiation of skeletal muscle myoblasts, both caspase activation in differentiating cells as well as signaling from apoptotic cells has been reported. Here, we review the non-apoptotic outcomes of caspase activity in a range of different model systems and attempt to integrate this knowledge.
Nachhaltigkeitsökonomie
(2014)
Residential and commercial buildings are responsible for about 40% of the EU’s total energy consumption. However, conscious, sustainable use of this limited resource is hampered by a lack of visibility and materiality of consumption. One of the major challenges is enabling consumers to make informed decisions about energy consumption, thereby supporting the shift to sustainable actions. With the use of Energy-Management-Systems it is possible to save up to 15%. In recent years, design approaches have greatly diversified, but with the emergence of ubiquitous- and context-aware computing, energy feedback solutions can be enriched with additional context information. In this study, we present the concept “room as a context” for eco-feedback systems. We investigate opportunities of making current state-of-the-art energy visualizations more meaningful and demonstrate which new forms of visualizations can be created with this additional information. Furthermore, we developed a prototype for android-based tablets, which includes some of the presented features to study our design concepts in the wild.
Business process infrastructures like BPMS (Business Process Management Systems) and WfMS (Workflow Management Systems) traditionally focus on the automation of processes predefined at design time. This approach is well suited for routine tasks which are processed repeatedly and which are described by a predefined control flow. In contrast, knowledge-intensive work is more goal and data-driven and less control-flow oriented. Knowledge workers need the flexibility to decide dynamically at run-time and based on current context information on the best next process step to achieve a given goal. Obviously, in most practical scenarios, these decisions are complex and cannot be anticipated and modeled completely in a predefined process model. Therefore, adaptive and dynamic process management techniques are necessary to augment the control-flow oriented part of process management (which is still a need also for knowledge workers) with flexible, context-dependent, goaloriented support.
People are getting older because of the demographic changes and the rate of disabled people is also going up. This article shows the challenge for BPMTool developer due to these circumstances. It illustrates how these changes impact the usage of BPM-Tools based on an Evaluation of an exemplary BPMTool (Cooper & Patterson, 2007) in terms of IT-Usability and IT-Accessibility. This evaluation was conducted in a research laboratory at the university.
Hybrid system models exploit the modelling abstraction that fast state transitions take place instantaneously so that they encompass discrete events and the continuous time behaviour for the while of a system mode. If a system is in a certain mode, e.g. two rigid bodies stick together, then residuals of analytical redundancy relations (ARRs) within certain small bounds indicate that the system is healthy. An unobserved mode change, however, invalidates the current model for the dynamic behaviour. As a result, ARR residuals may exceed current thresholds indicating faults in system components that have not happened. The paper shows that ARR residuals derived from a bond graph cannot only serve as fault indicators but may also be used for bond graph model-based system mode identification. ARR residuals are numerically computed in an off-line simulation by coupling a bond graph of the faulty system to a non-faulty system bond graph through residual sinks. In real-time simulation, the faulty system model is to be replaced by measurements from the real system. As parameter values are uncertain, it is important to determine adaptive ARR thresholds that, given uncertain parameters, allow to decide whether the dynamic behaviour in a current system mode is the one of the healthy system so that false alarms or overlooking of true faults can be avoided. The paper shows how incremental bond graphs can be used to determine adaptive mode-dependent ARR thresholds for switched linear time-invariant systems with uncertain parameters in order to support robust fault detection. Bond graph-based hybrid system mode identification as well as the determination of adaptive fault thresholds is illustrated by application to a power electronic system easy to survey. Some simulation results have been analytically validated.
Level-Synchronous Parallel Breadth-First Search Algorithms For Multicore and Multiprocessor Systems
(2014)
Breadth-First Search (BFS) is a graph traversal technique used in many applications as a building block, e.g.,~to systematically explore a search space. For modern multicore processors and as application graphs get larger, well-performing parallel algorithms are favourable. In this paper, we systematically evaluate an important class of parallel BFS algorithms and discuss programming optimization techniques for their implementation. We concentrate our discussion on level-synchronous algorithms for larger multicore and multiprocessor systems. In our results, we show that for small core counts many of these algorithms show rather similar behaviour. But, for large core counts and large graphs, there are considerable differences in performance and scalability influenced by several factors. This paper gives advice, which algorithm should be used under which circumstances.
Updating a shared data structure in a parallel program is usually done with some sort of high-level synchronization operation to ensure correctness and consistency. The realization of such high-level synchronization operations is done with appropriate low-level atomic synchronization instructions that the target processor architecture provides. These instructions are costly and often limited in their scalability on larger multi-core / multi-processor systems. In this paper, a technique is discussed that replaces atomic updates of a shared data structure with ordinary and cheaper read/write operations. The necessary conditions are specified that must be fulfilled to ensure overall correctness of the program despite missing synchronization. The advantage of this technique is the reduction of access costs as well as more scalability due to elided atomic operations. But on the other side, possibly more work has to be done caused by missing synchronization. Therefore, additional work is traded against costly atomic operations. A practical application is shown with level-synchronous parallel Breadth-First Search on an undirected graph where two vertex frontiers are accessed in parallel. This application scenario is also used for an evaluation of the technique. Tests were done on four different large parallel systems with up to 64-way parallelism. It will be shown that for the graph application examined the amount of additional work caused by missing synchronization is neglectible and the performance is almost always better than the approach with atomic operations.