Open Access

It is a euphemism to say that humans use tools. Humans possess a vast repertoire of tools they use every day. In fact, as language or bipedal locomotion, tool use is a hallmark of humans. Tool use has also been often viewed as an important step during evolution (van Schaik et al., 1999) or even as a marker of the evolution of human intelligence (Wynn, 1985). So a fundamental issue is, what are the cognitive and neural bases of human tool use? The present series of papers in this special topic represents the newest additions to that research topic.

Aus dem Projekt "Förderung angehender weiblicher Führungskräfte in kleinen und mittleren Unternehmen als CSR-Maßnahme"; ein Projekt der Hochschule Bonn-Rhein-Sieg im Rahmen des Programms "CSR-Gesellschaftliche Verantwortung im Mittelstand" gefördert durch das Bundesministerium für Arbeit und Soziales und durch den Europäischen Sozialfonds.

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).

Der Fachbereich Sozialversicherung der Hochschule Bonn-Rhein-Sieg blickt auf zehn erfolgreiche Jahre zurück. Seit Gründung des Fachbereichs im Jahr 2003 arbeiten Wissenschaftlerinnen und Wissenschaftler verschiedener Disziplinen auf dem Campus Hennef eng vernetzt im Untersuchungsfeld der Sozialversicherung.

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.

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.

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.

The Column spoke to Peter Kusch of the Bonn-Rhein-Sieg University of Applied Sciences in Rheinbach, Germany, about analyzing failure in the automotive industry.

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 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.

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.

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.

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.

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 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.

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.

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.

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.

Mit der ersatzlosen Streichung des § 114 InsO soll die Gläubigergleichbehandlung bereits im laufenden Verfahren gewährleistet und nicht mehr länger einer übergangsweisen "Privilegierung" zugunsten von gesicherten Gläubigern natürlicher Personen im Insolvenzverfahren "geopfert" werden.

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.

Propionic acidemia (PA) is a rare autosomal recessive organic aciduria resulting from defects in propionyl-CoA-carboxylase (PCC), a key enzyme of intermediate energy metabolism. PA mostly manifests during the neonatal period, when affected newborns develop severe metabolic acidosis and hyperammonemia. We present a previously healthy teenager, who suffered from acute fatigue and breathlessness. The patient was tachycardic, displayed a precordial heave and a systolic murmur. Cardiac investigations revealed severe dilated cardiomyopathy (DCM). Biochemical work up led to the diagnosis of PA. Remarkably, this patient of consanguineous Hispanic origin was in a good general health condition before the acute onset of DCM. Diagnosis of PA was confirmed by enzymatic and molecular genetic analysis, the latter revealing a novel homozygous mutation in the PCCB gene (c.1229G > A; p.R410Q). Residual PCC enzyme activity of approximately 14 % of normal was detected in patient’s lymphocytes and fibroblasts, thereby providing a possible explanation for the hitherto asymptomatic phenotype. Conclusion: Isolated DCM, although rare, can be the leading and/or sole symptom of late-onset PA. Therefore, patients with DCM should receive a comprehensive diagnostic evaluation including selective screening for inborn errors of metabolism.

Gene expression and cell growth rely on the intracellular concentration of amino acids, which in metazoans depends on extracellular amino acid availability and transmembrane transport. To investigate the impact of extracellular amino acid concentrations on the expression of a concentrative amino acid transporter, we overexpressed the main kidney proximal tubule luminal neutral amino acid transporter B0AT1-collectrin (SLC6A19-TMEM27) in MDCK cell epithelia. Exogenously expressed proteins co-localized at the luminal membrane and mediated neutral amino acid uptake. However, the transgenes were lost over few cell culture passages. In contrast, the expression of a control transgene remained stable. To test whether this loss was due to inappropriately high amino acid uptake, freshly transduced MDCK cell lines were cultivated either with physiological amounts of amino acids or with the high concentration found in standard cell culture media. Expression of exogenous transporters was unaffected by physiological amino acid concentration in the media. Interestingly, mycoplasma infection resulted in a significant increase in transgene expression and correlated with the rapid metabolism of L-arginine. However, L-arginine metabolites were shown to play no role in transgene expression. In contrast, activation of the GCN2 pathway revealed by an increase in eIF2α phosphorylation may trigger transgene derepression. Taken together, high extracellular amino acid concentration provided by cell culture media appears to inhibit the constitutive expression of concentrative amino acid transporters whereas L-arginine depletion by mycoplasma induces the expression of transgenes possibly via stimulation of the GCN2 pathway.

Culture, at least to some extent, is related to particular (individual and collective) experiences. In terms of education, this means that a learner, who experienced particular services in his/her past, might perceive such services as usual for educational culture and thus, expect them to be delivered in any kind of learning scenario. In German universities, education is meant to be a full-time job and usually is designed to provide a broad basis of theoretical and methodological knowledge. Achieving methodological competences is a core goal of German academic education: Once a student leaves the university, he/she is expected to decide about appropriate methods for any kind of problem (in the field of study and beyond) and how to modify the known methods in case of need. In contrast, in professional training, the learners have to study in extra-occupational situations (time is a serious issue) and might expect training that pointedly prepares them for very specific tasks. We assumed that scenarios of professional training have their own educational cultures. When designing learning contents and learning scenarios for professional training, it might be essential for the learning success to meet the learners’ expectations and contextual peculiarities. We found remarkable differences between the results of the investigated enterprises, but even more significant diversity between the results of the German enterprises and the priory investigated German universities. As a general conclusion we can assume that generalizing research results that were solely achieved from national university students might lead to an inappropriate design of learning scenarios for particular professional contexts. Professional training for a particular enterprise should be developed according to its specific educational culture.

The central concept behind Open Educational Resources (OER) is opening up the access to educational resources for stakeholders who are not the usual target user group. This concept must be perceived as innovative because it describes a general economic and social paradigm shift: Education, which formerly was limited to a specific group of learners, now, is promoted as a public good. However, despite very good intentions, internationally agreed quality standards, and the availability of the required technological infrastructure, the critical threshold is not yet met. Due to several reasons, the usefulness of OER is often limited to the originally targeted context. Questions arise if the existing quality standards for Technology Enhanced Learning (TEL) actually meet the specific requirements within the OER value chain, if the existing quality standards are applicable to OER in a meaningful way, and under which conditions related standards generally could support the exploitation of OER. We analyze quality standards for TEL and contrast the life cycle model of commercial learning resources against the life cycle model of OER. We investigate special demands on quality from the context of OER and, taking the former results into account, derive emergent quality criteria for OER. The paper concludes with recommendations for the design of OER and a future standard development.

Obwohl kulturbezogene Fragestellungen eine zentrale Rolle für die erfolgreiche Implementierung von Anwendungssystemen und IKT spielen, erfolgen kulturbezogene Untersuchungen in der Disziplin oft zu unkritisch: Kulturelle Kontexte werden in der Literatur häufig nicht klar abgegrenzt, und verwendete Begriffe werden nicht oder nur unzureichend definiert. Darüber hinaus werden kulturbezogene Untersuchungen, die eigentlich Besonderheiten abgegrenzter Gesellschaften (z. B. Kundensegmente) aufdecken sollen, oft ohne weitere Prüfung auf der Ebene von Nationalkultur untersucht. Die Problematik eines zu unkritischen und bisweilen sogar unangemessenen Umgangs mit kulturbezogenen Fragestellungen ist nicht auf die Wirtschaftsinformatik begrenzt sondern zieht sich durch nahezu alle Disziplinen, die "Kultur" als eine unter vielen Einflussgrößen betrachten. In dieser Arbeit wird ein praktischer Ansatz entwickelt, mit dessen Hilfe nicht nur der eigene kulturbezogene Forschungskontext abgegrenzt werden, sondern darüber hinaus auch noch herausgefunden werden kann, ob bereits verfügbare Forschungsansätze ggf. auf den eigenen Kontext passen könnten. Als Ergebnisse der Arbeit wurde ein Schritt-für-Schritt Leitfaden erstellt und eine Vergleichsbasis geschaffen, die auf einer in ihrem Umfang bislang einzigartigen Sammlung bereits verfügbarer Kulturbeschreibungsansätze beruht.

Die in den vergangenen Jahren gezielt geförderte Mobilität in Europa hat zu Arbeits- und Bildungsszenarien geführt, die besonders durch ihre nationale Heterogenität geprägt sind. Trotz aller Vorteile sind unerwünschte Nebeneffekte nicht auszuschließen.

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.

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.