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This paper presents the b-it-bots RoboCup@Work team and its current hardware and functional architecture for the KUKA youBot robot.We describe the underlying software framework and the developed capabilities required for operating in industrial environments including features such as reliable and precise navigation, flexible manipulation and robust object recognition.
Salts and proteins comprise two of the basic molecular components of biological materials. Kosmotropic/chaotropic co-solvation and matching ion water affinities explain basic ionic effects on protein aggregation observed in simple solutions. However, it is unclear how these theories apply to proteins in complex biological environments and what the underlying ionic binding patterns are. Using the positive ion Ca2+ and the negatively charged membrane protein SNAP25, we studied ion effects on protein oligomerization in solution, in native membranes and in molecular dynamics (MD) simulations. We find that concentration-dependent ion-induced protein oligomerization is a fundamental chemico-physical principle applying not only to soluble but also to membrane-anchored proteins in their native environment. Oligomerization is driven by the interaction of Ca2+ ions with the carboxylate groups of aspartate and glutamate. From low up to middle concentrations, salt bridges between Ca2+ ions and two or more protein residues lead to increasingly larger oligomers, while at high concentrations oligomers disperse due to overcharging effects. The insights provide a conceptual framework at the interface of physics, chemistry and biology to explain binding of ions to charged protein surfaces on an atomistic scale, as occurring during protein solubilisation, aggregation and oligomerization both in simple solutions and membrane systems.
Over the past two decades many low and middle income countries worldwide have started to extend the coverage and improve the functioning of public social protection systems. The research program on international policy diffusion provides empirical evidence that apart from domestic factors international interdependencies matter as well for national policy change in social protection. However, little is known about the governance structures mediating international policy diffusion in social protection.
The SpMV operation -- the multiplication of a sparse matrix with a dense vector -- is used in many simulations in natural and engineering sciences as a computational kernel. This kernel is quite performance critical as it is used, e.g.,~in a linear solver many times in a simulation run. Such performance critical kernels of a program may be optimized on certain levels, ranging from using a rather coarse grained and comfortable single compiler optimization switch down to utilizing architecural features by explicitly using special instructions on an assembler level. This paper discusses a selection of such program optimization techniques in this spectrum applied to the SpMV operation. The achievable performance gain as well as the additional programming effort are discussed. It is shown that low effort optimizations can improve the performance of the SpMV operation compared to a basic implementation. But further than that, more complex low level optimizations have a higher impact on the performance, although changing the original program and the readability / maintainability of a program significantly.
SpMV Runtime Improvements with Program Optimization Techniques on Different Abstraction Levels
(2016)
The multiplication of a sparse matrix with a dense vector is a performance critical computational kernel in many applications, especially in natural and engineering sciences. To speed up this operation, many optimization techniques have been developed in the past, mainly focusing on the data layout for the sparse matrix. Strongly related to the data layout is the program code for the multiplication. But even for a fixed data layout with an accommodated kernel, there are several alternatives for program optimizations. This paper discusses a spectrum of program optimization techniques on different abstraction layers for six different sparse matrix data format and kernels. At the one end of the spectrum, compiler options can be used that hide from the programmer all optimizations done by the compiler internally. On the other end of the spectrum, a multiplication kernel can be programmed that use highly sophisticated intrinsics on an assembler level that ask for a programmer with a deep understanding of processor architectures. These special instructions can be used to efficiently utilize hardware features in processors like vector units that have the potential to speed up sparse matrix computations. The paper compares the programming effort and required knowledge level for certain program optimizations in relation to the gained runtime improvements.
The Participation Act, introduced in the Netherlands in 2015, puts into practice the idea that every individual has to make a contribution in a participatory society. The Act includes aspects of income support, compulsory activities in return for benefits, and labour market reintegration. Drawing on 45 interviews, we provide insights into interactions between the individual financial and social situation, an individual’s position in society, and reintegration activities. The narratives show the fundamental need for individual freedom and societal meaning, recognition, and appreciation, as well as the complex circumstances in which social assistance recipients make decisions. Conflicts between those needs and the Act lead to the question of how personal and societal objectives can be reconciled.
An analysis of sharing string objects with the Java Virtual Machine was conducted; they are the most used objects in Java programs and they are immutable - thus they are read-only and easily identified. While the results are promising, it is clear that sharing more objects would result in better performance. Automatic object selection for sharing is non-trivial, because in the current state only read-only objects can be shared. This attribute can not be easily determined during runtime by an algorithm; the developer on the other hand can. This thesis presents the development of an Application Programmer Interface (API) that allows programmers to use the Java Virtual Machine (JVM) internal sharing functionality. Furthermore, we present the usage of the sharing API. Open-source software was used as real-world test cases. Afterwards the evaluation shows that the ratio between memory savings and start-up time overhead is reasonable.
A central objective of the German gambling law is to ensure the protection of minors and players (§ 1 Sentence 1 No. 3 GlüStV 2012). Since the year 2014 gambling facilities for commercial games of chance in gambling halls and restaurants have been certified by the German Safety Standards Authority [Technischer Überwachungsverein – TÜV]. Certification by government-accredited testing organizations based on internationally validated, interdisciplinary scientific expertise "Safeguarding the Protection of Minors and Players with Respect to Commercial Gambling in Germany – 2.0" is a quality assurance instrument from a regulatory perspective. It is in the interests of, in particular, excellent quality providers to ensure that they are also perceived as providing this level of quality. Certification leads to market separation. In so doing, the advantages of end-to-end certification should be greater than any disadvantages. Analysing the international environment shows that certifi cation initiatives are necessary and have been put in place in other sectors of the gambling industry.
The primary aim is quality assurance for a responsible handling of commercial games of chance offerings (responsible gambling). The presented testing catalogue for commercial gambling can also provide an impetus in the international context and, as appropriate, a set standard.
Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data. Hence the generation of robust reviewed global irradiance data is an essential contribution for the energy transition.
This paper presents the b-it-bots@Home team and its mobile service robot called Jenny – a service robot based on the Care-O-bot 3 platform manufactured by the Fraunhofer Institute for Manufacturing Engineering and Automation. In this paper, an overview of the robot control architecture and its capabilities is presented. The capabilities refers to the added functionalities from research and projects carried out within the Bonn-Rhein-Sieg University of Applied Science.
Autonomous mobile robots comprise of several hardware and software components. These components interact with each other continuously in order to achieve autonomity. Due to the complexity of such a task, a monumental responsibility is bestowed upon the developer to make sure that the robot is always operable. Hence, some means of detecting faults should be readily available. In this work, the aforementioned fault-detection system is a robotic black box (RBB) attached to the robot which acquires all the relevant measurements of the system that are needed to achieve a fault-free robot. Due to limited computational and memory resources on-board the RBB, a distributed diagnosis is proposed. That is, the fault diagnosis task (detection and isolation) is shared among an on-board component (the black box) and an off-board component (an external computer). The distribution of the diagnosis task allows for a non-intrusive method of detecting and diagnosing faults, in addition to the ability of remotely diagnosing a robot and potentially issuing a repair command. In addition to decomposing the diagnosis task and allowing remote diagnosability of the robot, another key feature of this work is the addition of expert human knowledge to aid in the fault detection process.
Currently, there are a lot of research activities dealing with gamma titanium aluminide (γ-TiAl) alloys as new materials for low pressure turbine (LPT) blades. Even though the scatter in mechanical properties of such intermetallic alloys is more distinctive as in conventional metallic alloys, stochastic investigations on γ -TiAl alloys are very rare. For this reason, we analyzed the scatter in static and dynamic mechanical properties of the cast alloy Ti-48Al-2Cr-2Nb. It was found that this alloy shows a size effect in strength which is less pronounced than the size effect of brittle materials. A weakest-link approach is enhanced for describing a scalable size effect under multiaxial stress states and implemented in a post processing tool for reliability analysis of real components. The presented approach is a first applicable reliability model for semi-brittle materials. The developed reliability tool was integrated into a multidisciplinary optimization of the geometry of a LPT blade. Some processes of the optimization were distributed in a wide area network, so that specialized tools for each discipline could be employed. The optimization results show that it is possible to increase the aerodynamic efficiency and the structural mechanics reliability at the same time, while ensuring the blade can be manufactured in an investment casting process.
Results from the EU-project iStoppFalls : feasibility, effectiveness, approach for fall prevention
(2016)
Brentuximab vedotin (SGN-35) is an antibody–drug conjugate with a high selectivity against CD30+ cell lines and more than 300-fold less activity against antigen-negative cells. In the last years, the results of many in vitro and in vivo studies have led to the fast approval of this drug to treat lymphoma patients. Another innovative method to treat tumor cells including lymphoma cells is the use cytokine-induced killer (CIK) cells, which have also been approved and proven to be a safe treatment with only minor adverse events. In this study, a possible additive effect when combining SGN-35 with CIK cells was investigated. The combinational treatment showed that it reduces the viability of CD30+ cell lines significantly in vitro. Additionally, the amount of lymphoma cells was significantly reduced when exposed to CIK cells as well as when exposed to SGN-35. A significant negative effect of SGN-35 on the function of CIK cells could be excluded. These results lead to the assumption that SGN-35 and CIK cells in combination might achieve better results in an in vitro setting compared to the single use of SGN-35 and CIK cells. Further investigations in in vivo models must be conducted to obtain a better understanding of the exact mechanisms of both treatments when applied in combination.
Noncooperative Game Theory
(2016)
Application Programming Interfaces (APIs) are a vital link between software components as well as between software and developers. Security APIs deliver crucial functionalities for programmers who see themselves in the increasing need for integrating security services into their software products. The ignorant or incorrect use of Security APIs leads to critical security flaws, as has been revealed by recent security studies. One major reason for this is rooted in usability issues. API Usability research has been deriving recommendations for designing usable APIs in general. Facing the growing relevance of Security APIs, the question arises, whether the observed usability aspects in the general space are already sufficient enough for building usable Security APIs. The currently available findings in the API Usability domain are selective fragments only, though. This still emerging field has not produced a comprehensive model yet. As a consequence, a first contribution of this paper is such a model that provides a consolidated view on the current research coverage of API Usability. On this baseline, the paper continues by conducting an analysis of relevant security studies, which give insights on usability problems developers had, when using Security APIs. This analysis leads to a proposal of eleven specific usability characteristics relevant for Security APIs. These have to be followed up by usability studies in order to evaluate how Security APIs need to be designed in a usable way and which potential trade-offs have to be balanced.
The mechanical properties of plastic components, especially if they are made of semi-crystalline polymers, are considerably influenced by the process conditions. The degree of crystallization influences thermal and mechanical properties. Even more important is the orientation of molecules due to stretching of the polymer melt. Anisotropic material properties are the result of such orientations. Up to now all these effects are not considered within the simulation models of blow molded parts.
Bone regeneration and replacement is a major focus in regenerative medicine since degenerative diseases and tumor surgery as well as accidents or dangerous recreational behavior is leading to an increasing need for bone reconstruction strategies. Especially for critical size bone defects, tissue engineering with mesenchymal stem cells is extensively studied because these cells are functioning as precursors for osteoblast in vivo. Nevertheless to reproduce the complex interaction of various factors in vitro is not an easy approach and further investigations have to be done. The status quo is summarized. A variety of growth and transcription factors are known to be involved in osteogenesis with bone morphogenetic proteins (BMPs) and the transcription factor Runx2 being the most extensively studied ones. But also PPAR γ and Osterix are generally regarded as the master regulators of osteoblast differentiation. Recently the large family of purinergic receptors has proven to be essential molecules in osteogenesis as well. In addition, scaffolding is needed to create a three-dimensional tissue. Recent developments in scaffold design are summarized, including natural and synthetic materials with or without the use of bioactive molecules constructed to mimic the natural environment. The status quo of scaffold fabrication methods such as 3D nanoprinting and their influence on cell-scaffold interactions is discussed. In this review we summarize the most interesting results and our related work focusing on two joined approaches: 1) the complex interaction of the most promising factors improving or accelerating osteogenic differentiation and ii) the development of scaffold materials with osteoconductive and osteoinductive properties.
During the last 50 years, a broad range of visible light curing resin based composites (VLC RBC) was developed for restorative applications in dentistry. Correspondingly, the technologies of light curing units (LCU) have changed from UV to visible blue light, and there from quartz tungsten halogen over plasma arc to LED LCUs increasing their light intensity significantly. In this thesis, the influence of the curing conditions in terms of irradiance, exposure time and irradiance distribution of LCU on reaction kinetics as well as corresponding mechanical and viscoelastic properties were investigated.
Agricultural activities within city boundaries have a long history in both developed and developing countries. In this paper, a broad approach to Urban AgriCulture (UAC) is used, one that includes the production of crops in urban and peri-urban areas and ranges in developed countries from allotment gardens over community gardens to semi-entrepreneurial self-harvest farms and fully commercialized agriculture. With an empirical case study on UAC Initiatives in the Bonn/Rhein-Sieg region this work fills a gap since the lack of comprehensive and comparative studies on urban agriculture (UA) currently makes it difficult for researchers to identify the benefits of UA activities.
Agricultural activities within the city boundaries have a long history in both developed and developing countries. Especially in developing countries these activities contribute to food security and the mitigation of malnutrition (food grown for home consumption). They generate additional income and contribute to recreation, environmental health as well as social interaction. In this paper, a broad approach of Urban AgriCulture is used, which includes the production of crops in urban and peri-urban areas and ranges in developed countries from allotment gardens (Schrebergarten) over community gardens (Urban Gardening) to semi-entrepreneurial self-harvest farms and fully commercialized agriculture (Urban Farming). Citizens seek to make a shift from traditional to new (sustainable) forms of food supply. From this evolves a demand for urban spaces that can be used agriculturally. The way how these citizens’ initiatives can be supported and their contribution to a resilient and sustainable urban food system increasingly attracts attention. This paper presents an empirical case study on Urban AgriCulture initiatives in the Bonn-Rhein-Sieg region (Germany). Urban AgriCulture is still a niche movement with the potential to contribute more significantly to urban development and constitute a pillar of urban quality of life.
Human beings spend much time under the influence of artificial lighting. Often, it is beneficial to adapt lighting to the task, as well as the user’s mental and physical constitution and well-being. This formulates new requirements for lighting - human-centric lighting - and drives a need for new light control methods in interior spaces. In this paper we present a holistic system that provides a novel approach to human-centric lighting by introducing simulation methods into interactive light control, to adapt the lighting based on the user's needs. We look at a simulation and evaluation platform that uses interactive stochastic spectral rendering methods to simulate light sources, allowing for their interactive adjustment and adaption.