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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.
Temperature Dependency of Morphological Structure of Thermoplastic Polyurethane using WAXS and SAXS
(2016)
Polyurethanes achieved an exceptional position among the most important organic polymers due to their highly specific technological application areas. Polyurethanes represent a polyaddition product of isocyanate and diols. In terms of their enormous industrial importance, the chemistry of isocyanates has been extensively studied.
3D-Printing is an efficient method in the field of additive manufacturing. In order to optimize the properties of manufactured parts it is essential to adapt the curing behavior of the resin systems with respect to the requirements. Thus, effects of resin composition, e.g. due to different additives such as thickener and curing agents, on the curing behavior have to be known. As the resin transfers from a liquid to a solid glass the time dependent ion viscosity was measured using DEA with flat IDEX sensors. This allows for a sensitive measurement of resin changes as the ion viscosity changes two to four decades. The investigated resin systems are based on the monomers styrene and HEMA. To account for the effects of copolymerization in the calculation of the reaction kinetics it was assumed that the reaction can be considered as a homo-polymerization having a reaction order n?1. Then the measured ion viscosity curves are fitted with the solution of the reactions kinetics - the time dependent degree of conversion (DC-function) - for times exceeding the initiation phase representing the primary curing. The measured ion viscosity curves can nicely be fitted with the DC-function and the determined fit parameters distinguish distinctly between the investigated resin compositions.
Sharpening the Educational Toolset - Promoting Professional Development of University Lecturers
(2016)
WiFi-based Long Distance (WiLD) networks have emerged as a promising alternative approach for Internet in rural areas. However, the MAC layer, which is based on the IEEE802.11 standard, comprises contiguous stations in a cell and is spatially restricted to a few hundred meters at most. In this work, we summarize efforts by different researchers to use IEEE802.11 over long-distances. In addition, we introduce WiLDToken, our solution to optimizing the throughput and fairness and reducing the delay on WiLD links. Compared to previous alternative MAC layers protocols for WiLD, our focus is on optimizing a single link in a multi-radio multi-channel mesh. We implement our protocol in the ns-3 network simulator and show thatWiLDToken is superior to an adapted version of the Distributed Coordination Function (DCF) for different link distances. We find that the throughput on a single link is close to the physical data-rate without a major decrease over longer distances.
WiFi-based Long Distance (WiLD) networks have emerged as a promising alternative technology approach for providing Internet in rural areas. An important factor in network planning of these wireless networks is estimating the path loss. In this work, we present various propagation models we found suitable for point-to-point (P2P) operation in the WiFi frequency bands. We conducted outdoor experiments with commercial offthe- shelf (COTS) hardware in our testbed made of 7 different long-distance links ranging from 450 m to 10.3 km and a mobile measurement station. We found that for short links with omni-directional antennas ground-reflection is a measurable phenomenon. For longer links, we show that either FSPL or the Longley-Rice model provides accurate results for certain links. We conclude that a good site survey is needed to exclude influences not included in the propagation models.
Nachhaltiges Innovationsmanagement in KMU: Eine empirische Untersuchung zu Living Labs as a Service
(2016)
Die neue europäische Umweltstrategie der Integrierten Produktpolitik fordert von produzierenden kleinen und mittleren Unternehmen (KMU) eine eigenverantwortliche und produktbezogene Nachhaltigkeitsstrategie. Obgleich die Gestaltung von IKT-Services in nachhaltigkeitsrelevanten Bereichen ein großes Marktpotential verspricht, birgt das Innovationsmanagement für KMU einige Risiken. Um diese Herausforderungen zu adressieren motiviert diese Arbeit Living Labs, als Innovationsinfrastruktur, um den spezifischen Bedarfen von KMU für ein nachhaltiges Innovationsmanagement gerecht zu werden. Auf der Basis von 15 semi-strukturierten Interviews mit 7 KMU, die IKT-Lösungen in den Bereichen Wohnen und Mobilität entwickeln, wurden Herausforderungen sowie etablierte Strategien für ein nachhaltiges Innovationsmanagement erhoben sowie Potenziale und mögliche Risiken von Living Labs exploriert. Die Studie zeigt KMU spezifische Bedarfe auf, die eine Anpassung des Living Lab Ansatzes als Service-Dienstleistungen erforderlich machen.
Die Ergebnisqualität medizinischer Rehabilitationsleistungen wird häufig über „Patient Reported Outcomes“ (PROs) gemessen. Die Bedeutung von PROs für die Nutzenbeurteilung von therapeutischen Interventionen wird häufig unterschätzt (Brettschneider et al., 2011; Calvert et al., 2013). Es wird untersucht, inwieweit sich PROs in „harten“ Endpunkten wie z. B. Beitragszahlungen der Versicherten in die Sozialversicherung widerspiegeln.
In der Ergebnisdarstellung der Reha-QM-Outcome Studie der DRV Baden-Württemberg und des Qualitätsverbunds Gesundheit konnte gezeigt werden, dass Kliniken eines Verbundes, die ein gemeinsames, auf aktivem Benchmarking und Von-Einander-Lernen gegründetes Qualitätsmanagement (Basis QMS Reha®) anwenden, ein Jahr nach der Reha etwas bessere Ergebnisse in relevanten Outcome-Parametern (u. a. subjektiver Reha-Nutzen, geleistete Rentenversicherungsbeiträge) erzielen als der Durchschnitt der Kliniken (Toepler et al., 2015). Der vorliegende Beitrag stellt die verbundinterne Analyse der Studienergebnisse dar und geht der Frage nach, welche QM-Elemente einen positiven Einfluss auf die Outcome-Parameter ausüben.
Neben der Verbesserung des Gesundheitszustandes sind der Erhalt der Beschäftigungsfähigkeit und die berufliche (Wieder-)Eingliederung zentrale Ziele der Rehabilitationsleistungen der Deutschen Rentenversicherung. In der „Reha-QM-Outcome-Studie“ wurden sowohl mittels Patientenfragebogen Angaben zum subjektiven Nutzen der Behandlung als auch mittels Routinedaten der Rentenversicherung Angaben zum Erwerbsstatus erhoben, so dass eine Gegenüberstellung beider Zieldimensionen erfolgen kann.
Return to Work (RTW) stellt ein wesentliches Outcomekriterium für die Abbildung der Effektivität medizinischer Rehabilitationsmaßnahmen dar. Dabei hängt die Höhe der RTW-Quote u. a. von Messmethode, Messzeitpunkt und Stichprobe ab (Streibelt, Egner, 2012). RTW wird häufig mit dem bloßen Status der Erwerbstätigkeit oder Arbeitsfähigkeit gleichgesetzt, wobei kritisiert werden kann, dass dabei der Aspekt einer dauerhaften beruflichen Wiedereingliederung zu wenig Berücksichtigung findet.
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.