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As soon as data is noisy, knowledge as it is represented in an information system becomes unreliable. Features in databases induce equivalence relations—but knowledge discovery takes the other way round: given a relation, what could be a suitable functional description? But the relations we work on are noisy again. If we expect to record data for learning a classification of objects then it can well be the real data does not create a reflexive, symmetric and transitive relation although we know it should be. The usual approach taken here is to build the closure in order to ensure desired properties. This, however, leads to overgeneralisation rather quickly.
This book constitutes the proceedings of the 14th International Conference on Relational and Algebraic Methods in Computer Science, RAMiCS 2014 held in Marienstatt, Germany, in April/May 2014. The 25 revised full papers presented were carefully selected from 37 submissions. The papers are structured in specific fields on concurrent Kleene algebras and related formalisms, reasoning about computations and programs, heterogeneous and categorical approaches, applications of relational and algebraic methods and developments related to modal logics and lattices.
On nothing
(2014)
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.
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.
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.
PhD Project Management
(2014)
Psychische Belastungen stehen in ihren negativen Ausprägungen als psychische Fehlbeanspruchungen im Zentrum der Diskussion im Arbeitsschutz. Ihr kontinuierlicher Anstieg sowie die Verbindung mit verschiedenen psychischen und körperlichen Erkrankungen werden durch zahlreiche internationale Studien belegt. Die Herausgeber möchten mit dem Praxishandbuch eine Hilfe für diejenigen bieten, die mit der Aufgabe des Erkennens und der Prävention psychischer Fehlbelastungen konfrontiert sind. Die Anregungen sind für alle Akteure im Bereich der Verhütung arbeitsbedingter Gesundheitgefahren geeignet: Betriebsärzte, Sozialmediziner, Psychologen, Sicherheitsfachkräfte, Führungskräfte, Betriebsräte und sonstige Ansprechpartner, Personalverantwortliche und Sozialpädagogen.
The Fifth International Workshop on Domain-Specific Languages and Models for Robotic Systems (DSLRob'14) was held in conjunction with the 2014 International Conference on Simulation, Modeling, and Programming for Autonomous Robots (SIMPAR 2014), October 2014 in Bergamo, Italy. The main topics of the workshop were Domain-Specific Languages (DSLs) and Model-driven Software Development (MDSD) for robotics. A domain-specific language is a programming language dedicated to a particular problem domain that offers specific notations and abstractions that increase programmer productivity within that domain. Model-driven software development offers a high-level way for domain users to specify the functionality of their system at the right level of abstraction. DSLs and models have historically been used for programming complex systems. However recently they have garnered interest as a separate field of study. Robotic systems blend hardware and software in a holistic way that intrinsically raises many crosscutting concerns (concurrency, uncertainty, time constraints, ...), for which reason, traditional general-purpose languages often lead to a poor fit between the language features and the implementation requirements. DSLs and models offer a powerful, systematic way to overcome this problem, enabling the programmer to quickly and precisely implement novel software solutions to complex problems within the robotics domain.
Mobbing
(2014)
Stress
(2014)
Vor dem Hintergrund knapper Ressourcen, dem zunehmendem Reha-Bedarf und der politischen Diskussion um eine demografische Anpassung der Reha-Budgets gewinnt der Nachweis der Ergebnisqualität medizinischer Reha-Leistungen weiter an zentraler Bedeutung (z. B. Haaf, 2005; Steiner et al., 2009). Die kontinuierliche und klinikvergleichende Überprüfung der Behandlungsergebnisse ist darüber hinaus ein wichtiger Baustein eines funktionierenden Qualitätsmanagements (Schmidt et al., in press). Sie ermöglicht ein "Lernen von den Besten" und führt zu organisatorischen Lernprozessen (Toepler et. al., 2010).
Application systems are often advertised with features, and features are used heavily for requirements man- agement. However, often software manufacturers only have incomplete information about the features of their software. The information is distributed over different sources, such as requirements documents, issue trackers, user manuals, and code. In this paper, we research the occurrence of feature information in open source software engineering data. We report on a case study with three open source systems. We analyze what information about features can be found in issue trackers and user documentation. Furthermore, we study the abstraction levels on which the features are described, how feature information is related, and we discuss the possibility to discover such information semi-automatically. To mirror the diversity of software development contexts, we choose open source systems, which are quite different, e.g., in the rigor of issue tracker usage. The results differ accordingly. One main result is that the user documentation did not provide more accurate information than the issue tracker compared to a provided feature list. The results also give hints on how the management of feature relevant information can be supported.
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.
Breadth-First Search is a graph traversal technique used in many applications as a building block, e.g., to systematically explore a search space or to determine single source shortest paths in unweighted graphs. For modern multicore processors and as application graphs get larger, well-performing parallel algorithms are favorable. In this paper, we systematically evaluate an important class of parallel algorithms for this problem and discuss programming optimization techniques for their implementation on parallel systems with shared memory. 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 performance behavior. But, for large core counts and large graphs, there are considerable differences in performance and scalability influenced by several factors, including graph topology. 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.
Werkstattgeflüster
(2014)
Seit der Saison 2014 veröffentlichen wir alle 4 Monate unseren Newsletter "Werkstattgeflüster", der unseren Unterstützern, Förderern und Freunden gleichermaßen einen Einblick in unser Projekt geben soll. Über die Saison verteilt möchten wir so verstärkt über die Events und unsere Zusammenarbeit mit unseren Sponsoren berichten und unseren Mitgliedern die Chance geben, Ihre Arbeit im Team vorzustellen.
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.
We investigated graphene structures grafted with fullerenes. The size of the graphene sheets ranges from 6400 to 640,000 atoms. The fullerenes (C60 and C240) are placed on top of the graphene sheets, using different impact velocities we could distinguish three types of impact. Furthermore, we investigated the changes of the vibrational properties. The modified graphene planes show additional features in the vibronic density of states.
Matrix metalloproteinases (MMPs) are matrix-degrading enzymes that are over-expressed in joints of rheumatoid arthritis (RA) patients. However, the contribution of specific MMPs for the development of arthritic joints is unknown. This study is aimed at studying the role of matrix metalloproteinase-9 (MMP-9) in mice, using the K/BxN serum-transfer model of RA. Arthritis was induced in Balb/c mice by injecting K/BxN serum. Development of arthritis was followed in these mice by measuring ankle thickness and clinical index score. MMP-9 expression in the joints of mice killed at various time points during the disease progression was determined by gelatin zymography using ankle lysates. We found that MMP-9 expression increased with the severity of arthritis. Importantly MMP-9 deficient mice injected with K/BxN serum showed a milder form of arthritis in comparison to the control C57BL/6 mice injected with K/BxN serum. We therefore conclude that MMP-9 promotes arthritis in mice.
The analytical pyrolysis technique hyphenated to gas chromatography–mass spectrometry (GC–MS) has extended the range of possible tools for the characterization of synthetic polymers and copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at temperatures of 500–1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer or copolymer sample are formed. The pyrolysis products are chromatographically separated using a fused-silica capillary column and are subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminates the need for pretreatment by performing analyses directly on the solid or liquid polymer sample. In this article, application examples of analytical pyrolysis hyphenated to GC–MS for the identification of different polymeric materials in the plastic and automotive industry, dentistry, and occupational safety are demonstrated. For the first time, results of identification of commercial light-curing dental filling material and a car wrapping foil by pyrolysis–GC–MS are presented.
Gas chromatography with flame-ionization detection (FID) and gas chromatography-mass spectrometry (GC/MS) with electron impact ionization (EI) and chemical ionization (PCI and NCI) were successfully used for separation and identification of commercially available longchain primary alkyl amines. The investigated compounds were used as corrosion inhibiting and antifouling agents in a water-steam circuit of energy systems in the power industry. Solidphase extraction (SPE) with octadecyl bonded silica (C18) sorbents followed by gas chromatography were used for quantification of the investigated Primene JM-T™ alkyl amines in boiler water, condensate and superheated steam samples from the power plant. Amine formulations from Kotamina group favor formation of protective layers on internal surfaces and keep them free from corrosion and scale. Alkyl amines contained in those formulations both render the environment alkaline and limit the corrosion impact of ionic and gaseous impurities by formation of protective layers. Moreover, alkyl amines limit scaling on heating surfaces of boilers and in turbine, ensuring failure-free operation. Application of alkyl amine formulation enhances heat exchange during boiling and condensation processes. Alkyl amines with branched structure are more thermally stable than linear alkyl amines, exhibit better adsorption and effectiveness of surface shielding. As a result, application of thermostable long-chain branched alkyl amines increases the efficiency of anti-corrosive protection. Moreover, the concentration of ammonia content in water and in steam was also considerably decreased.
Analytical pyrolysis technique hyphenated to gas chromatography/mass spectrometry (Py-GC/MS) has extended the range of possible tools for characterization of synthetic polymers/copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at elevated temperature between 500 and 1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer/copolymer sample are formed. The pyrolysis products are chromatographically separated by using a fused silica capillary column and subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminate the need for pre-treatment by performing analyses directly on the solid or liquid polymer sample.
In this paper, application examples of the analytical pyrolysis hyphenated to gas chromatography/mass spectrometry for the identification of different polymeric materials in the plastic and automotive industry, dentistry and occupational safety are demonstrated. For the first time results of identification of commercially light-curing dental filling material and a car wrapping foil by pyrolysis-GC/MS are presented.
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.
Förderpreise 2014
(2014)
An apple a day keeps the doctor away’. While it may be true that a balanced diet is a prerequisite for good health, how good is what we eat and drink every day? And is it actually possible to fulfil every customer desire with the vast array of foodstuffs on offer? BSE, dioxin in eggs, EHEC sprouts: in the light of repeated food safety crises, the issue of quality assurance as well as customer-oriented quality management has become of prime importance for the agri-food industry.
The RoCKIn@Home Challenge
(2014)
The RoCKIn@Work Challenge
(2014)
The title of the annual report 2013 "Shaping change: The University Addresses Society‘s Probing Challenges" reveals the great importance placed on social, economic and technological changes at the university.
This key aspect thus runs through the contents of the 90-page annual report like a common thread, without losing track of the enormous variety of research and teaching at Bonn-Rhein-Sieg University. Whether the exploration of gaps in robot safety during a European Intensive Programme, a report about the Philipines crisis region from a graduate who has worked as an organizer for Care International, or the chapter "What does change look like?" – The annual report provides the full spectrum of opportunities, activities and findings of university members.
Rendering techniques for design evaluation and review or for visualizing large volume data often use computationally expensive ray-based methods. Due to the number of pixels and the amount of data, these methods often do not achieve interactive frame rates. A view direction based rendering technique renders the users central field of view in high quality whereas the surrounding is rendered with a level of detail approach depending on the distance to the users central field of view thus giving the opportunity to increase rendering efficiency. We propose a prototype implementation and evaluation of a focus-based rendering technique based on a hybrid ray tracing/sparse voxel octree rendering approach.
Das Management von Sicherheit und Gesundheit bei der Arbeit beinhaltet die Praevention psychischer Fehlbelastungen und psychischer Erkrankungen. Die gesetzliche Grundlage der Praeventionsaktivitaeten der gesetzlichen Unfallversicherung wird aufgefuehrt. Anschliessend wird verdeutlicht, in welchen Handlungsfeldern und mit welchen Instrumenten die gesetzliche Unfallversicherung die Praevention psychischer Erkrankungen in den Betrieben unterstuetzt. Als theoretischer Rahmen fuer Praeventionsmassnahmen werden das Dreiebenenmodell psychischer Belastungen (Mitarbeiter, Unternehmen, Gesellschaft) und das Dreiebenen-Interventionsmodell psychischer Erkrankungen skizziert. Die betriebliche Praevention erfolgt im Idealfall auf der Basis konkreter innerbetrieblicher Regelungen. Dies wird beispielhaft fuer den Umgang mit E-Mails und die Regelungen zur Erreichbarkeit naeher beschrieben.
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.
Software repository data, for example in issue tracking systems, include natural language text and technical information, which includes anything from log files via code snippets to stack traces. However, data mining is often only interested in one of the two types e.g. in natural language text when looking at text mining. Regardless of which type is being investigated, any techniques used have to deal with noise caused by fragments of the other type i.e. methods interested in natural language have to deal with technical fragments and vice versa. This paper proposes an approach to classify unstructured data, e.g. development documents, into natural language text and technical information using a mixture of text heuristics and agglomerative hierarchical clustering. The approach was evaluated using 225 manually annotated text passages from developer emails and issue tracker data. Using white space tokenization as a basis, the overall precision of the approach is 0.84 and the recall is 0.85.
We explore the potential of stereoscopic 3D (S3D) vision in offering distinct gameplay using an S3D-specific game called Deepress3D. Our game utilizes established S3D design principles for optimizing GUI design, visual comfort and game mechanics which rely on depth perception in time-pressured spatial conflicts. The game collects detailed S3D player metrics and allows players to choose between different, evenly matched strategies. We conducted a between subjects study comparing S3D and monoscopic versions of Deepress3D that examined player behavior and performance and measured user-reported data on presence, simulator sickness, and game experience.
Deep Gaming
(2014)
How to create a distinct user experience of Stereo 3D in Interactive Entertainment & Virtual Reality Gaming Stereoscopic 3D (S3D) vision offers spatial visual perception by presenting two separate and different This article or re envision the, creative economy different versions of games in it up. By authors behind the same sheet, of primary medical dental and operator. If I gently rubbed miles chest wouldn't know. Listing infohere at a way through, sixth grade level by the layout and memory. Hats off adjust the bass and restart automatic benefit. Try to be fooled into serious topics by playing with a lot. Creating general many other people, with new digital games allow their impact! The hunt for example my google, searches has learned. These badges this development phases to work it is in my year.
Schon der Titel des Jahresberichts 2013 "Den Wandel gestalten: Hochschule stellt sich drängenden Fragen der Gesellschaft" offenbart, welche Bedeutung gesellschaftlichen, wirtschaftlichen und technologischen Veränderungen an der Hochschule beigemessen wird.
Dieses Schwerpunkthema zieht sich folglich wie ein roter Faden durch die Inhalte des 90 Seiten starken Jahresberichts, ohne dabei die enorme Vielfalt von Forschung und Lehre an der Hochschule Bonn-Rhein-Sieg aus den Augen zu verlieren. Ob nun die Ergründung von Lücken in der Robotersicherheit während eines europäischen Intensivprogramms, ein Bericht aus dem Krisengebiet Philippinen von einer Absolventin, die als Organisatorin für Care International tätig ist, oder das Kapitel "Was bedeutet Wandel?" - der Jahresbericht bildet das ganze Spektrum der Möglichkeiten, Aktivitäten und Erkenntnisse der Hochschulangehörigen ab.
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.
Das sogenannte „Deutschlandstipendium“ ist 2010 ins Leben gerufen worden. Gemäß den gesetzlichen Vorgaben sollen die Stipendien nach Begabung und Leistung vergeben werden. Darüber hinaus sollen auch gesellschaftliches Engagement oder besondere soziale, familiäre oder persönliche Umstände berücksichtigt werden. Bei der Finanzierung sind die Hochschulen zunächst auf das Einwerben privater Fördermittel angewiesen, die von Bund und Land um denselben Betrag aufgestockt werden. Die privaten Mittelgeber können für die von ihnen anteilig finanzierten Stipendien festlegen, aus welchen Studiengängen ihre Stipendiaten ausgewählt werden sollen. Die Hochschulen haben jedoch darauf zu achten, dass ein Drittel aller zu vergebenden Stipendien ohne eine entsprechende Zweckbindung vergeben werden. Einen direkten Einfluss auf die Auswahl einzelner Kandidaten dürfen die Förderer nicht haben. Vor diesem Hintergrund sind die Hochschulen angehalten, Anreize für private Förderer zu schaffen und parallel Bewerbungs- und Auswahlverfahren zu konzipieren, die die genannten gesetzlichen Vorgaben einhalten. Dadurch entsteht bei den Hochschulen ein erheblicher Verwaltungsaufwand. Zu dessen Reduzierung wird in diesem Artikel ein transparenter, nachvollziehbarer, zeit- und kostensparender Prozess durch einen programmierten Workflow beschrieben.
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.
The ability to track moving people is a key aspect of autonomous robot systems in real-world environments. Whilst for many tasks knowing the approximate positions of people may be sufficient, the ability to identify unique people is needed to accurately count people in the real world. To accomplish the people counting task, a robust system for people detection, tracking and identification is needed.
Robots, which are able to carry out their tasks robustly in real world environments, are not only desirable but necessary if we want them to be more welcome for a wider audience. But very often they may fail to execute their actions successfully because of insufficient information about behaviour of objects used in the actions.
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.
This work describes extensions to the well-known Distributed Coordination Function (DCF) model to account for IEEE802.11n point-to-point links. The developed extensions cover adaptions to the throughput and delay estimation for this type of link as well peculiarities of hardware and implementations within the Linux Kernel. Instead of using simulations, the approach was extensively verified on real-world deployments at various link distances. Additionally, trials were conducted to optimize the CWmin values and the number of retries to maximize throughput and minimize delay. The results of this work can be used to estimate the properties of long-distance 802.11 links beforehand, allowing the network to be planned more accurately.
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 den letzten Jahren ist das Thema Nachhaltigkeit zu einem Schlüsselthema in vielen wissenschaftlichen und gesellschaftlichen Diskursen geworden. Ausgehend von natur-, technik-, politik- und zunehmend wirtschaftswissenschaftlichen Auseinandersetzung mit Fragestellungen im Kontext von Nachhaltigkeit, sind diese in den Mittelpunkt gesellschaftlicher und politischer Wahrnehmung gerückt.
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.
Exposure to microgravity conditions causes cardiovascular deconditioning in astronauts during spaceflight. Until now, no specific drugs are available for countermeasure, since the underlying mechanism is largely unknown. Endothelial cells (ECs) and smooth muscle cells (SMCs) play key roles in various vascular functions, many of which are regulated by purinergic 2 (P2) receptors. However, their function in ECs and SMCs under microgravity conditions is still unclear. In this study, primary ECs and SMCs were isolated from bovine aorta and verified with specific markers. We show for the first time that the P2 receptor expression pattern is altered in ECs and SMCs after 24 h exposure to simulated microgravity using a clinostat. However, conditioned medium compensates this change in specific P2 receptors, for example, P2X7. Notably, P2 receptors such as P2X7 might be the important players during the paracrine interaction. Additionally, ECs and SMCs secreted different cytokines under simulated microgravity, leading into a pathogenic proliferation and migration. In conclusion, our data indicate P2 receptors might be important players responding to gravity changes in ECs and SMCs. Since some artificial P2 receptor ligands are applied as drugs, it is reasonable to assume that they might be promising candidates against cardiovascular deconditioning in the future.