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Robust Indoor Localization Using Optimal Fusion Filter For Sensors And Map Layout Information
(2014)
A principal step towards solving diverse perception problems is segmentation. Many algorithms benefit from initially partitioning input point clouds into objects and their parts. In accordance with cognitive sciences, segmentation goal may be formulated as to split point clouds into locally smooth convex areas, enclosed by sharp concave boundaries. This goal is based on purely geometrical considerations and does not incorporate any constraints, or semantics, of the scene and objects being segmented, which makes it very general and widely applicable. In this work we perform geometrical segmentation of point cloud data according to the stated goal. The data is mapped onto a graph and the task of graph partitioning is considered. We formulate an objective function and derive a discrete optimization problem based on it. Finding the globally optimal solution is an NP-complete problem; in order to circumvent this, spectral methods are applied. Two algorithms that implement the divisive hierarchical clustering scheme are proposed. They derive graph partition by analyzing the eigenvectors obtained through spectral relaxation. The specifics of our application domain are used to automatically introduce cannot-link constraints in the clustering problem. The algorithms function in completely unsupervised manner and make no assumptions about shapes of objects and structures that they segment. Three publicly available datasets with cluttered real-world scenes and an abundance of box-like, cylindrical, and free-form objects are used to demonstrate convincing performance. Preliminary results of this thesis have been contributed to the International Conference on Autonomous Intelligent Systems (IAS-13).
„Ein Wort gibt das andere“ – zwischenmenschliche Kommunikation folgt bestimmten Regeln. Wer diese Mechanismen durchschaut, kann nicht nur eigene Gesprächsziele besser erreichen, sondern auch andere Menschen leichter verstehen und erfolgreicher mit ihnen interagieren.
Nicht von ungefähr zählt Kommunikationskompetenz zu den gefragtesten Soft Skills in Beruf und Alltag. Diese Einführung in die Theorie und Praxis der Kommunikation erläutert die Prinzipien effizienter Kommunikation nach wie vor ein Klassiker zur Veranschaulichung von gruppendynamischen Prozessen und Rollenverhalten. Das Lehrbuch erklärt das Phänomen der Kommunikation anhand verschiedener sozialpsychologischer Untersuchungen, Theorien, Beispiele und Sichtweisen, regt zu einer erweiterten Reflexion darüber an und liefert konkrete Hinweise und Übungen, welche die eigene Kommunikationspraxis effektiv verbessern.
(Verlagsangaben)
Adapting plans to changes in the environment by finding alternatives and taking advantage of opportunities is a common human behavior. The need for such behavior is often rooted in the uncertainty produced by our incomplete knowledge of the environment. While several existing planning approaches deal with such issues, artificial agents still lack the robustness that humans display in accomplishing their tasks. In this work, we address this brittleness by combining Hierarchical Task Network planning, Description Logics, and the notions of affordances and conceptual similarity. The approach allows a domestic service robot to find ways to get a job done by making substitutions. We show how knowledge is modeled, how the reasoning process is used to create a constrained planning problem, and how the system handles cases where plan generation fails due to missing/unavailable objects. The results of the evaluation for two tasks in a domestic service domain show the viability of the approach in finding and making the appropriate goal transformations.
Humans exhibit flexible and robust behavior in achieving their goals. We make suitable substitutions for objects, actions, or tools to get the job done. When opportunities that would allow us to reach our goals with less effort arise, we often take advantage of them. Robots are not nearly as robust in handling such situations. Enabling a domestic service robot to find ways to get a job done by making substitutions is the goal of our work. In this paper, we highlight the challenges faced in our approach to combine Hierarchical Task Network planning, Description Logics, and the notions of affordances and conceptual similarity. We present open questions in modeling the necessary knowledge, creating planning problems, and enabling the system to handle cases where plan generation fails due to missing/unavailable objects.
This review is divided into two interconnected parts, namely a biological and a chemical one. The focus of the first part is on the biological background for constructing tissue-engineered vascular grafts to promote vascular healing. Various cell types, such as embryonic, mesenchymal and induced pluripotent stem cells, progenitor cells and endothelial- and smooth muscle cells will be discussed with respect to their specific markers. The in vitro and in vivo models and their potential to treat vascular diseases are also introduced. The chemical part focuses on strategies using either artificial or natural polymers for scaffold fabrication, including decellularized cardiovascular tissue. An overview will be given on scaffold fabrication including conventional methods and nanotechnologies. Special attention is given to 3D network formation via different chemical and physical cross-linking methods. In particular, electron beam treatment is introduced as a method to combine 3D network formation and surface modification. The review includes recently published scientific data and patents which have been registered within the last decade.
This paper gives an overview of the development of Fair Trade in six European countries: Austria, France, Germany, the Netherlands, Switzerland and the United Kingdom. After the description of the food retail industry and its market structures in these countries, the main European Fair Trade organizations are analyzed regarding their role within the Fair Trade system. The following part deals with the development of Fair Trade sales in general and with respect to the products coffee, tea, bananas, fruit juice and sugar. An overview of the main activities of national Fair Trade organizations, e.g. public relation activities, completes the analysis. This study shows the enormous upswing of Fair Trade during the last decade and the reasons for this development. Nevertheless, it comes to the conclusion that Fair Trade is still far away from being an essential part of the food retail industry in Europe.
Methylmalonic and propionic acidemia (MMA/PA) are inborn errors of metabolism characterized by accumulation of propionic acid and/or methylmalonic acid due to deficiency of methylmalonyl-CoA mutase (MUT) or propionyl-CoA carboxylase (PCC). MMA has an estimated incidence of ~ 1: 50,000 and PA of ~ 1:100'000 -150,000. Patients present either shortly after birth with acute deterioration, metabolic acidosis and hyperammonemia or later at any age with a more heterogeneous clinical picture, leading to early death or to severe neurological handicap in many survivors. Mental outcome tends to be worse in PA and late complications include chronic kidney disease almost exclusively in MMA and cardiomyopathy mainly in PA. Except for vitamin B12 responsive forms of MMA the outcome remains poor despite the existence of apparently effective therapy with a low protein diet and carnitine. This may be related to under recognition and delayed diagnosis due to nonspecific clinical presentation and insufficient awareness of health care professionals because of disease rarity.
Die Norm EN ISO 13849-1 stellt explizite Anforderungen an sicherheitsgerichtete SPS-Software. Wie lassen sich diese im Maschinenbau praxisgerecht umsetzen? Mit dieser Frage hat sich ein von der DGUV gefördertes und an der Hochschule Bonn-Rhein-Sieg durchgeführtes Projekt beschäftigt. Der Beitrag skizziert die Vorgehensweise zur möglichen Umsetzung der normativen Anforderungen. Diese Vorgehensweise ist unabhängig von der verwendeten Sicherheits-SPS und daher allgemein anwendbar. Es wird auf insgesamt 10 dokumentierte Beispiele und einen ausführlichen Forschungsbericht verwiesen, die downloadbar sind.
Automatisierungstechnik
(2014)
Die Automatisierungstechnik wird aus praktischer Sicht mit vielen Beispielen und zahlreichen Bildern veranschaulicht. Studenten ingenieurwissenschaftlicher Fachrichtungen sowie Ingenieure und Techniker in der Ausbildung und der beruflichen Praxis können sich auf dem Stand der Technik selbständig einarbeiten.
Nachhaltigkeit aus institutionenökonomischer Perspektive am Beispiel der Schiefergasförderung
(2014)
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.
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.
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.
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.
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.
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.
Nachhaltigkeitsökonomie
(2014)
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.
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.
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.
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.
Simulation of thermal behavior during friction stir welding process for predicting residual stresses
(2014)
The RoCKIn@Work Challenge
(2014)
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.
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.
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.
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].
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.
Masterkurs IT-Controlling
(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.
SOA-Readiness of REST
(2014)
Service Security Revisited
(2014)
The case for basic human needs in coaching: A neuroscientific perspective - The SCOAP Coach Theory
(2014)
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.
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.