Column Experiments Simulating Various Scenarios for Arsenic Mobilisation in Bangladesh

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Big Data in Bicycle Traffic: A user-oriented guide to the use of smartphone-generated bicycle traffic data

For cycling to be attractive, the infrastructure must be of high quality. Due to the high level of resources required to record it locally, the available data on the volume of cycling traffic has to date been patchy. At the moment, the most reliable and usable numbers seem to be derived from permanently installed automatic cycling traffic counters, already used by many local authorities. One disadvantage of these is that the number of data collection points is generally far too low to cover the entirety of a city or other municipality in a way that achieves truly meaningful results. The effect of side roads on cycling traffic is therefore only incompletely assessed. Furthermore, there is usually no data at all on other parameters, such as waiting times, route choices and cyclists’ speed. This gap might in future be filled by methods such as GPS route data, as is now possible by today’s widespread use of smartphones and the relevant tracking apps. The results of the project presented in this guide have been supported by the BMVI [Federal Ministry of Transport and Digital Infrastructure] within the framework of its 2020 National Cycling Plan. This research project seeks to investigate the usability of user data generated using a smartphone app for bicycle traffic planning by local authorities. In summary, it can be stated that, taking into account the factors described in this guide, GPS data are usable for bicycle traffic planning within certain limitations. (The GPS data evaluated in this case were provided by Strava Inc.) Nowadays it is already possible to assess where, when and how cyclists are moving around across the entire network. The data generated by the smartphone app could be most useful to local authorities as a supplement to existing permanent traffic counters. However, there are a few aspects that need to be considered when evaluating and interpreting the data, such as the rather fitness-oriented context of the routes surveyed in the examples examined. Moreover, some of the data is still provided as database or GIS files, although some online templates that are easier to use are being set up, and some can already be used in a basic initial form. This means that evaluation and interpretation still require specialist expertise as well as human resources. However, the need for these is expected to reduce in the future with the further development of web interfaces and supporting evaluation templates. For this to work, developers need to collaborate with local authorities to work out what parameters are needed as well as the most suitable formats. This research project carried out an approach to extrapolating cycling traffic volumes from random samples of GPS data over the whole network. This was also successfully verified in another municipality. Further research is still nevertheless required in the future, as well as adaptation to the needs of different localities. Evidence for the usability of GPS data in practice still needs to be acquired in the near future. The cities of Dresden, Leipzig and Mainz could be taken as examples for this, as they have all already taken their first steps in the use of GPS data in planning for and supporting cycling. These steps make sense in the light of the increasing digitisation of traffic and transport and the growing amount of data available as a result – despite the limitations on these data to date – so that administrative bodies can start early in building up the appropriate skills among their staff. The use of GPS data would yield benefits for bicycle traffic planning in the long run. In addition, the active involvement of cyclists opens up new possibilities in communication and citizen participation – even without requiring specialist knowledge. This guide delivers a practical introduction to the topic, giving a comprehensive overview of the opportunities, obstacles and potential offered by GPS data

Safe Cycling in Winter - Results of a use case on the role of snow and ice removal in the city of Hamburg, Germany

An increase in cycling mode share and cycling performance is an essential part of future transport development (Buehler and Pucher 2011; Schwanen 2015). In order to achieve the climate goals of the Federal Republic of Germany, the share of cycling must be significantly increased (BMVI 2021). An important part of this is to make cycling safe also in harsh weather conditions as seen in winter. While cycling mode shares have increased in the other seasons in recent years, a slump in cycling performance can be observed especially in winter (Nobis 2019). Studies to date have attributed this to weather conditions (temperature, precipitation) (Winters et al. 2011) and, above all, to the declining subjective feeling of safety among cyclists. Many German municipalities are therefore working on a winter service concept for cycling in order to mak.e cycling safe even in winter conditions. ... Therefore, an environmentally sound alternative for winter maintenance on segregated cycle paths that is acceptable to cyclists must be found. In many German cities but also globally, the challenge is to find a balanced solution between environmental protection and safe cycling. However, possible alternatives have to go through an approval process before they can be used. To solve those questions, we conducted several surveys which are summarized in this paper. lt consists of five sections: Section 2 highlights the wishes and demands on cycling(infrastructure) in winter from the cyclists' point of view. In section 3, the current state of winter maintenance in German cities is reviewed. Section 4 describes the selection and ecological footprint of alternative gritting materials, while section 5 describes the experiences of users in a field test. [From: Introduction

Epidemiologie nosokomialer Infektionen und die Abhängigkeit krankenhausassoziierter Komplikationen von der Personalbesetzung in der Neonatologie

Nosokomiale Infektionen bei Früh- und Neugeborenen stellen aufgrund ihrer hohen Inzidenz und Mortalität eine große Herausforderung für die moderne Versorgung dar. Außerdem sind sie Indikatoren für die Pflegequalität, wie auch Verletzungen und Gefäßschädigungen. In dieser retrospektiven Querschnittsstudie wurden die epidemiologische Situation nosokomialer Infektionen auf den neonatologischen Stationen der Universitätskinderklinik Leipzig für das Jahr 2006 beleuchtet, die Abhängigkeit der genannten Komplikationen von Plegepersonalqualifikation und –quantität untersucht, sowie die Stationsauslastung und Personalbesetzung mit deutschen Empfehlungen verglichen. Die Inzidenz systemischer Infektionen lag sowohl auf der neonatologischen Intensiv- als auch auf der Nachsorgestation unter dem deutschlandweiten Durchschnitt. Dagegen traten Lokalinfekte wie Windel-/ Mundsoor und Konjunktivitiden häufig auf. Das beobachtete Keimspektrum zeigte das aus der Literatur bekannte Bild, multiresistente Keime traten nicht auf. Bei der Untersuchung der Abhängigkeiten zeigte sich für die Intensivstation eine signifikante Häufung von Candidainfektionen bei geringerer Stationsauslastung und höherer Personalbesetzung, unabhängig von der Qualifikation des Personals. Auf der Nachsorgestation wurde eine vermehrte Zahl systemischer Infektionen bei höherem Anteil von Schwestern am Gesamtpersonal festgestellt. Beide Stationen waren gegenüber den Empfehlungen fast das ganze Jahr überbelegt und unterbesetzt. Gründe für die gefundenen Abhängigkeiten wurden vermutet in Informationsverlust und Trittbrettfahrerproblemen in größeren Kollektiven und verstärkter minimal-handling-Pflege und verstärkter Hygiene-Compliance in Stresssituationen. Die geringe Inzidenz systemischer Infektionen spricht für eine sichere Pflege und ist demnach sehr positiv zu bewerten, trotzdem sollten die Hintergründe für das Auftreten der Lokalinfekte, auch wenn sie meist einen milden Verlauf zeigten, überprüft werden. Eine Gesamtbeurteilung der Pflege ist anhand der gemachten Untersuchungen nicht möglich, da aufgrund der Retrospektive keinerlei Faktoren wie Belastungseinschätzung der Schwestern, Lerneinschätzung der Schüler oder Betreuungseinschätzung der Eltern einfließen konnten

E-Portfolios an der Technischen Universität Dresden: Durchführung einer explorativen Studie zur Erhebung des Status quo und Gestaltung eines Einsatzszenarios im Bereich der bildungstechnologischen Ausbildung von Lehramtsstudierenden

Klausuren und Tests sind Prüfungsformen, die geeignet sind, die fachliche Kompetenz von Studierenden zu bewerten. Dabei sind es gerade soziale, personelle und methodische Kompetenzen, über die zukünftigen Lehrerinnen und Lehrer im Unterrichtsalltag verfügen sollten. E-Portfolios scheinen das Potential zu haben, Prüfungen offener und im ganzheitlichen Sinne kompetenzorientierter zu gestalten. Vorliegende Arbeit thematisiert Mehrwerte sowie problematische Aspekte bei der Einführung von E-Portfolio-Arbeit in der akademischen Ausbildung von Lehrerinnen und Lehrern und formuliert Empfehlungen für die erfolgreiche Implementierung dieser Methode und der notwendigen Werkzeuge. Dazu wird untersucht, welchen Stellenwert Portfolios und E-Portfolios derzeit in der Lehrerausbildung an der Technischen Universität Dresden haben, welche Software speziell für die vorherrschenden Rahmenbedingungen geeignet ist und welche positiven und negativen Aspekte bei der didaktischen Konzeption eines Lernszenarios mit E-Portfolio als Lern- und Prüfungsform zu berücksichtigen sind

Vergleichende kalorimetrische Untersuchungen zur Ermittlung der mikrobiellen Aktivitäten von Pseudomonas putida

In der vorliegenden Arbeit wurden Untersuchungen zur mikrobiellen Aktivität von Pseudomonas putida DSM12735 durchgeführt. Als Messgröße diente die mikrobielle Wärmeleistung, basierend auf dem Stoffumsatz durch die Mikroorganismen. Ziel war es, die Vor- und Nachteile der verwendeten Kalorimeter herauszuarbeiten. Dafür wurden klassische Batch-Wachstumskurven aufgenommen. Ein weiteres Ziel bestand darin, eine Methode zur schnellen kalorimetrischen Detektion der mikrobiellen Aktivität insbesondere für die stationäre Phase zu entwickeln. In dieser Phase findet kein signifikanter Stoffumsatz statt. Durch das gezielte Auslösen einer zweiten Wachstumsphase und damit einem Stoffumsatz wird die mikrobielle Aktivität kalorimetrisch wieder messbar. Eingesetzt wurden folgende Kalorimeter: der Thermal Activity Monitor 2277 (TAM) mit den Kalorimetern Micro Reaction System 2250-4 ml und 2250-20 ml (kurz: TAM-4ml, TAM-20ml), das IC-Chip-Kalorimeter FCC22 (Institut für Physikalische Chemie, TU Freiberg) und das Kalorimeter Micro-DSC II (MDSC)

Zu den frühbronzezeitlichen Gruppen in Süddeutschland

Die süddeutsche Frühbronzezeit wird im Allgemeinen aufgrund der Beigaben und Grabsitten in mehrere kleine Gruppen unterteilt, die sich voneinander abgrenzen sollen. Eine genauere Betrachtung der Gruppen unter Einbeziehung neuester Funde und Befunde läßt diese Unterteilung jedoch fragwürdig erscheinen, da sich wesentlich mehr verbindende als trennende Elemente innerhalb der Frühbronzezeit in Süddeutschland feststellen lassen, so daß eine kleinräumige Abgrenzung im herkömmlichen Sinne nicht mehr gerechtfertigt erscheint.Generally, the Early Bronze Age in Southern Germany has been subdivided into several separate groups on the basis of grave goods and funeral practices. Upon closer examination – including the latest finds and features – this separation appears questionable. Instead, it becomes apparent that within the Early Bronze Age there are more elements, which are common to these groups than differences, which separate then. A regional separation in the traditional sense does not seem to be justified

A rate dependent experimental and numerical analysis of adhesive joints under different loading directions

Adhesively bonded joints subjected to dynamic loading demand reliable and accurate measurement techniques to capture their rate dependent traction–separation behaviour. Particularly challenging is the measurement of damage and failure processes which are fundamental to develop the corresponding cohesive zone models. This paper proposes a new experimental methodology for the characterisation of rate-dependent behaviour of adhesive joints. The results of the adopted approach have been used to calibrate a rate-dependent numerical cohesive model proposed to simulate the failure of adhesive joints. The procedure was benchmarked against quasi-static DCB and ENF experiments

On the rate dependent behaviour of epoxy adhesive joints: experimental characterisation and modelling of mode I failure

The increasing use of adhesive joints in dynamic applications require reliable measurements of the rate-dependent stress-displacement behaviour. The direct measurement of the stress-displacement curve is necessary when using cohesive models in discretised solutions of boundary value problems in solid mechanics. This paper aims to investigate the rate-dependent tensile failure of adhesive joints by using a new experimental methodology – it relies upon the combination of the stress wave propagation theory and digital image correlation methods on high speed footage to quantify the tensile stress and the dissipated energy respectively. For this purpose, the Split Hopkinson Bar methodology was employed – the experimental configuration was optimised using numerical modelling. To prove the sensitivity of our framework, two different adhesives are characterised at different loading rates: the adhesive failure strength was found to increase considerably with the strain rate, while the plastic deformation of these adhesives was reduced. The film adhesive showed superior performance over the particle toughened one. In the final part, a rate-dependent cohesive zone model is proposed, one which captures the measured behaviour and which has the potential to be used in industrial applications

On the protectiveness of additively manufactured mouthguards

A mouthguard is a piece of equipment worn in sports worldwide to greatly reduce the chance of orodental injuries. This work uses a newly developed method for testing and analysing mouthguards subjected to high impact energies of up to 100 J. This method allows investigation and comparison between the use of additive manufacturing, and current best mouthguard manufacturing technology of thermoforming with Ethylene-vinyl acetate (EVA). The impact experiments are conducted using a drop tower and high-speed images are captured for the further analysis. Important physical parameters such as peak force, impulse and dissipated energy in the mouthguard are determined. The results revealed that the additively manufactured mouthguards made from Arnitel® ID 2045 lead to a peak force and impulse of impact that is on average 10% and 25% lower, respectively, than that experienced when using the EVA mouthguard. A lower peak force and impulse is preferred as it reduces the chance of an orodental injury occurring. The research shows that previously mouthguards have been tested at impact energies far lower than those experienced in impact prone sports such as field hockey. When using impacts with higher energies, the findings show that additive manufacturing provides a viable technology for manufacturing mouthguards, which offers many new benefits