45 research outputs found
A camera trap survey of nocturnal mammals on former farmland in the eastern Free State Province, South Africa, 10 years after removing livestock
No full text<p>This archive contains the data and R scripts used for the following study:</p>
<p>Buschke, F.T.(unpublished). A camera trap survey of nocturnal mammals on former farmland in the eastern Free State Province, South Africa, 10 years after removing livestock</p>
<p>A written description of the research methodology can be obtained from the manuscript. Please consult the README.txt file for a detailed outline of all the files in this archive.</p>
<p>Any comments or inquiries can be directed to the author, Falko Buschke ([email protected])</p>
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Life cycle assessment and evaluation of sustainable product design strategies for combined cycle power plants
No full textDer weltweite Anstieg des Bedarfs an Primärenergie und das Wachstum des weltweiten Bruttoinlandsprodukts geht einher mit der Zunahme damit verbundener Emissionen. Aktuellen wissenschaftlichen Studien zufolge beträgt der Anteil des Energiesektors (Energiewirtschaft, Industrie und Verkehr) 83 % der weltweiten Treibhausgasemissionen. Der Klimawandel und die Projektion der Auswirkungen von Treibhausgasemissionen auf die Atmosphäre werden inzwischen auch auf politischer Ebene akzeptiert und weitergehende Maßnahmen diskutiert. Da aber Zugang zu Elektrizität und nachhaltige Entwicklung untrennbar verknüpft sind, stellt sich die Frage, wie diese Aufgabe innerhalb der nächsten Jahre gelöst werden kann. Weiterhin ergibt sich gleichzeitig durch die verbleibende Laufzeit des aktuellen Kraftwerksparks, je nach Szenario, für Deutschland im Jahr 2020 eine Versorgungslücke von bis zu 12.000 MWh. Ein Teil der Lösung dieser Problematik liegt in der nachhaltigen Gestaltung von Kraftwerken. Die Erstellung der Lebenszyklusanalyse eines GuD-Kraftwerks aus Sicht eines Herstellers in höchster Detailtiefe bildet daher den Hauptbestandteil dieser Arbeit. Erst die Darstellung des gesamten Produktsystems sowie der Bilanzierungsergebnisse ermöglichen das Aufzeigen von Verbesserungspotentialen. Die Systemgrenzen für die Ökobilanz umfassen alle Abschnitte des Produktlebenszyklus (Materialien, Fertigung, Transport, Betrieb, Wartung und End of Life). Die Erfassung der Materialmengen und Energiedaten liefert die Sachbilanz für alle Komponenten und Lebensphasen. In der Interpretation der Ergebnisse der Ökobilanz, insbesondere für die Kategorie Globale Erwärmung in kg CO2e überwiegen die Emissionen der Betriebsphase naturgemäß. Die Ergebnisse wurden aber für alle Wirkungskategorien und Lebensphasen erarbeitet. Auf Basis der erarbeiteten Module der Ökobilanz wurden die Umweltprofile verschiedener Konfigurationen und Betriebsszenarien dargestellt und stehen damit als Entscheidungshilfe bereits während der Produktentwicklung zur Verfügung. Die Darstellung der Auswirkungen von Designentscheidungen auf den ökologischen Fußabdruck des Produktsystems in einer aggregierten Form vereinfacht das Verständnis für Kunden und kann damit in die Kaufentscheidung einbezogen werden. Weiterhin wurde die Basis für ein Reporting der Treibhausgasemissionen nach dem GHG Protokoll erstellt. Die Ergebnisse werden außerdem in Form einer Typ II Produktumwelterklärung nach ISO 14021 veröffentlicht und als Referenzwert für die Berechnung der Emissionsfaktoren für den jeweiligen Strommix bereitgestellt.The growth of the national GDP on a worldwide level and the associated increasing demand for primary energy inevitably result in higher emissions levels. According to recent international scientific studies the energy sector (including electricity generation, industrial activities and traffic) contributes up to 83 % to the worldwide greenhouse gas emissions. Climate change and the projection of its impacts have been acknowledged also on the political level and concise measures are being considered. Since access to electricity and sustainable development are inseparable, the question arises whether and how adequate answers can be given within the coming years. Furthermore, the definite lifetime of the existing power plant fleet will result in a gap of up to 12.000 MWh in 2020, depending on the scenario. One part of the answer lies in the sustainable design of power plants. The main contribution of this work is therefore the life cycle analysis of a combined cycle power plant from of a manufacturer’s perspective. The visualisation of the entire product system and the results of the impact assessment facilitate the determination of improvement potential. The system boundaries for this study include all relevant phases of the product life cycle (materials, manufacturing, transport, operation, service and end of life). The life cycle inventory consists of all bills of materials and energy consumption for all components and life cycle phases. The interpretation of the results of the impact assessment showed the expected significant contribution in kg CO2e for the emission of the full load operation. Nevertheless, the results for all impact categories over the entire lifecycle are given. Various operation scenarios and configurations can now be analysed based on the elaborated modules, and can now serve as decision support already during product development. The visualisation of impacts of design decisions on the ecological footprint of the product system in an aggregated form enables decision makers and customers to evaluate design choices and decide accordingly. Furthermore, the starting point for the greenhouse gas reporting according to the GHG Protocol over the entire product life cycle has been established. Eventually, the results will be published as Type II Environmental Product Declaration acc. ISO 14021 and serve as reference value for the determination of the CO2-intensity of the respective grid mix
Analysing the assemblage dispersion field
No full text<p>This archive contains the data and R scripts used for the following study:</p>
<p>Buschke, F.T., Brendonck, L. & Vanschoenwinkel (2015). Simple mechanistic models can partially explain local but not range-wide co-occurrence of African mammals. Global Ecology and Biogeography doi: 10.1111/geb.12316</p>
<p>Please be sure to read the README.txt file first, before attempting to use these data.</p>
<p>A written description of the research methodology can be obtained from the manuscript.</p>
<p>Any comments or inquiries can be directed to the lead author, Falko Buschke ([email protected])</p>
<p> </p
Recommended from our members
Session A4: A Working Guide for Site Specific Evaluations of Fish Protection and Bypass Systems
No full textPresenting Author Bio: Falko Wagner - Since 09/2012 Lecturer at several Universities Since 07/2005 Founding and leading the Institute of aquatic ecology and fish biology Jena 06/2003-06/2005 Research associate at the Bauhaus-University Weimar 04/1999-06/2003 Research associate and PhD-student at the Friedrich-Schiller- University Jena 10/1993-12/1998 Diploma student at the Friedrich-Schiller-University Jena 03/1989-12/1991 Work as fishermen (inland fisheries)Abstract: The importance of an unaffected fish migration in rivers to maintain or establish near-natural fish communities represents a scientific and a social consensus. This is underlined by European laws as the European Water Directive, demanding the ecological connectivity of rivers. In the last decades increasingly fish protection and bypass systems were developed and installed to reduce mortality at hydro power plants and water abstraction facilities. To prove their efficiency, usually a site-adapted monitoring is necessary. Until now neither German nor European standards for a recommended monitoring design are available. This leads to inconsistent methodological approaches, concerning sampling design and data analysis of individual studies. Therefore results of those studies are hard to compare. Generally links of causes and effects might be masked by methodological background noise. The German Federal Environment Agency (UBA) therefore funded a report to provide the basis for a monitoring working guide including methodological guidelines for site specific evaluation process. The working guide in its current state provides guidelines for preparation, conduction of the experiment and data analysis. Its aim is to simplify the selection of the appropriate sampling methods, sampling time and target fishes (species and development stage). 20 metrics are given as quantitative base for an evaluation of fish protection and bypass systems. Metric thresholds for a sufficient site specific ecological connectivity are not given yet, due to the lack of a sufficient database for their calibration on ecological demands. The first version of the working guide will be revised and further updated under the direction of the German Association for Water, Wastewater and Waste (DWA). The presentation of the current state aims to facilitate the discussion of the methodological approach to evaluate fish protection and bypass systems
Examining COVID-19-triggered changes in spatial connectivity patterns in the European air transport network up to June 2021
No full textThe integrity of international supply chain operations heavily relies on air transport services to facilitate the movement of goods and enable human interactions between its stakeholders. With the outbreak of COVID-19 in Europe around March 2020, air transport networks have been subject to profound alterations. Although the link between variations in air transport service levels and changes in user costs for network-wide travel has been analysed extensively, few studies have examined the extent to which severe network shrinkage events lead to a reduction in network connectivity, which is therefore difficult to predict. This paper investigates how the COVID-19 pandemic has structurally altered the European air transport network in 2020/21 and how these changes have deteriorated users' ease when utilising network-wide air transport services. To do this, the paper estimates the change in average quickest path length at the airport level during different stages of this period. Results indicate there is strong heterogeneity in airports' susceptibility to pandemic-induced network changes, with both regional variations and variations in the airline type serving individual airports. Furthermore, topological features of individual airports are found to determine airport susceptibility. The findings are discussed in terms of their implications for locational decisions in supply chain designs
Bias due to MEasurement Reactions In Trials to improve health (MERIT) : protocol for research to develop MRC guidance
No full textAcknowledgements The authors would like to acknowledge Dr. Angela Rodrigues and Prof. Falko Sniehotta who are co-authors working on the systematic review of the question-behaviour effect on health-related behaviours and Dr. Katerina Kassavou who is a co-author of the three rapid reviews described in this protocol. Funding The MERIT study is funded by the MRC/NIHR Methodology Research Programme (reference MC_PC_17229); funders have had no role in the design of the study or the writing of this manuscript.Peer reviewe
Designing a passive dynamic SLS-3D printable ankle-foot orthosis
No full textAn ankle-foot orthosis (AFO) is a medical aid that helps individuals with deficient walking patterns achieve a more natural gait. There are various types of AFOs prescribed for different reasons. This thesis specifically focuses on passive dynamic ankle-foot orthoses (PD-AFOs) and even within that branch a very specific type: the carbon dorsal leaf spring orthosis. This type of AFO leverages the body’s biomechanics and gravitational forces to store and release energy at precise phases of the gait pattern, helping to restore some of the ankle function. Furthermore, they address the issue of excessive plantar flexion during the swing phase of gait, which can result in foot drop or an undesirable foot-slamming motion.To ensure optimal fit and functionality, these orthoses are custom-made to provide the best fit for the lower leg and foot of each individual. Currently, the manufacturing process for these orthoses involves labour-intensive carbon composite layering techniques, which require significant effort and expertise.An alternative AFO concept was designed, which aims to replicate the behaviour of existing carbon dorsal leaf spring orthoses using SLS-3D printing. This direction was explored as additive manufacturing excels in one-off production and eliminates the need for manual labour, offering cost-effective and efficient production of personalized items. This case is therefore carried out for the companies Parts on Demand, a selective laser sintering (SLS) 3D-printing company, and Livit Ottobock Care, an orthopedics company, to further investigate the feasibility of such an orthosis.This study involved multiple design iterations, primarily focused on the stiffness behaviour of the AFO to create a novel SLS printable design that exhibits similar stiffness characteristics and gait influence compared to the existing carbon dorsal leaf spring AFOs produced by Livit Ottobock Care, whilst maintaining comparable weight and cost.A model was created to parametrically refine SLS printable AFOs based on scanned lower leg and foot data for repeatable results using different feet. Subsequently, prototypes were fabricated using this model to validate the quantitative stiffness behaviour and qualitative correction of user gait resulting in an orthosis with a comparable function to the baseline carbon dorsal leaf spring orthosis.Initial results seem promising for the feasibility of SLS printing PD-AFOs, but requires further validation, as many aspects related to their longevity were excluded from this study. These factors include its fracture resistance over longer periods of time, whether stiffness fatigue will occur, or how the AFO will behave mediolaterally. Nonetheless, producing an SLS-printed orthosis can provide benefits in the long run which for example include not only customized and well-fitting orthoses but also tailored stiffness characteristics for each individual, enhancing the function of the ankle and foot during walking. However, it is important to note that research in this area is currently insufficient.Integrated Product Desig
Applicability of the Pushover Method for the Seismic Assessment of URM Structures in Groningen: A Case Study of a Low-Rise Apartment Building
No full textIn Groningen, seismic activity has increased due to the extraction of gas in the area. A large-scale research campaign has been launched with the aim to assess and safeguard structures in the region. However, an accurate assessment of these buildings turned out to be a challenge, due to the nonlinear behaviour of the masonry and the dynamic nature of a seismic load. A Nonlinear Time History (NLTH) analysis takes into account both these factors, but the computational demand of such a method is considerable. Another method that is widely used to analyse the seismic response of a structure is the Modal Response Spectrum (MRS) method. The computational demand of this method is considerably less compared to NLTH, but nonlinear material behaviour is only taken into account in an indirect manner via a behaviour factor, and the results are considered to be too conservative. A third method is the Nonlinear Pushover (NLPO) method. It takes nonlinear material behaviour into account and compared to NLTH, NLPO is computationally more efficient. Furthermore, an advantage is that it separates capacity from demand. Even though the NLPO method is commonly applied worldwide, its validity still needs to be proven for the Groningen case. Both objectives were studied by looking into a single case study, consisting of a low-rise URM apartment building. The behaviour of the structure is characterised by a weak and strong direction, in which the weak direction is characterised by a relatively low stiffness and lateral capacity compared to the strong direction. The seismic response of the structure is determined according to the MRS, NLPO and NLTH methods. Furthermore, the NLPO analyses are executed using two different computational discretisation methods, namely continuum FEM and macro EFM. DIANA is used as a FEM solver for the MRS, NLPO and NLTH analyses and 3MURI is used for the EFM model. Moreover, a modal and uniform lateral load pattern are taken into account for the NLPO analyses. The conclusions which are drawn from the case study can generally be applied to low-rise URM apartment buildings in Groningen. However, it must be noted that significant alterations in geometry and building materials might influence the results. Furthermore, modelling assumptions have been applied, and it is important to note that the possible influence of these assumptions, may partially limit the extent of the conclusions. Moreover, several limitations are inherent to the studied methods, and cannot be accounted for somehow. All analyses are performed by incrementally increasing the seismic load until one of the near collapse limit state criteria according to NPR 9998 is met. Furthermore, three target displacement methods are evaluated: the capacity spectrum method according to NPR 9998, the regular N2-method, included in the Eurocode 8, and an adaptation of the N2-method which is developed specifically for URM structures by Guerinni. The performance of the structure according to each of the methods is studied subsequently, by looking into the force-displacement behaviour, displacement profile and damage at failure, failure mechanisms and the maximum admissible seismic load. Two significant disadvantages of macro EFM were identified when comparing the results of the NLPO analyses using 3MURI and DIANA. First, the fact that out-of-plane behaviour is not taken into account in 3MURI could significantly influence the behaviour of a structure in terms of base shear capacity, which is especially true when structures are characterised by an extremely low total length of piers in the in-plane direction. Furthermore,DIANA allows for a more gradual softening behaviour, which helps the post-peak force redistribution. As a consequence, the maximum admissible seismic load according to DIANA could be higher. However, despite the two aforementioned disadvantages of the macro EFM method as implemented in 3MURI, all other relevant results of both methods are similar. The fact that the two identified disadvantages of 3MURI can only result in more conservative results, suggests that macro EFM, as implemented in 3MURI, is a suitable computational discretisation method for the seismic assessment according to the NLPO method for low-rise URM apartment buildings in Groningen. However, it should be taken into account that the conservativeness of 3MURI could lead to a significantly larger amount of required retrofitting, in comparison with DIANA. The applicability of the NLPO method is reviewed by comparing the results of the MRS, NLPO and NLTH methods. Similar behaviour of the structure according to the NLPO and NLTH method was captured, which suggests that the NLPO method is a suitable analysis method for the studied typology. The maximum admissible seismic load using the target displacement method according to NPR 9998 is in-line with the NLTH analysis. However, the governing load case made use of a uniform load pattern, which returns a structural behaviour different than that obtained by NLTH analyses, as can be seen from the force-displacement behaviour. If only the capacity curve according to the modal load pattern would be considered, then the allowable seismic load according to NLTH is similar to that of NLPO using the target displacement method of Eurocode 8. Furthermore, from the results of the case study can be concluded that the choice of target displacement method has a significant influence on the maximum admissible seismic load. For the case study, NPR 9998 is more conservative in the strong direction, and Eurocode 8 is more conservative in the weak direction. Regarding the MRS method, very conservative results were found. A reason that was found for these conservative results is that the prescribed behaviour factor by NPR 9998 is too low for the case study when compared to that derived from the NLPO analysis. However, even with a larger behaviour factor, the results according to the MRS method would still be conservative in the weak direction.Civil Engineering | Structural Engineerin
Multi-use E-bikes for a post pandemic era
No full textThe graduation project is commissioned by Bayck, a small E-bike start-up which focuses on designing affordable and simple e-bikes. The company is looking for new market opportunities and perceives the Corona outbreak as a potential trigger for behaviour change towards mobility and e-bikes. To find a relevant design direction for Bayck, information is gathered in four steps; First, the pre-pandemic mobility is discussed, then how it is affected by the pandemic. E-bike users are interviewed to understand the new use needs. Finally, future visions from different perspectives are discussed to find a relevant context in which Bayck can design a new product. From the analysis, it is concluded that the new Bayck product needs to be personal, enable multi-usage and invite the user to relax while going from A to B. The conclusions of the analysis are put together in a design brief. An ideation is performed to come up with a design direction fitting the design brief. To conclude the ideation phase, it is decided to design an e-bike that operates on a removable battery(-ies), also usable as a personal power-bank. A storyboard is drawn to depict the ideal use situation. The current Bayck model is taken apart to understand how an e-bike works and what should be integrated in the new design. The concept is toned down to a level of feasibility: Two batteries of 18V are required to enable the user to charge its devices, but also use the 36V e-bike motor. The challenge is made to simplify the e-bike as much as possible and separate the electronics as much as possible from the frame. The whole electronic system will be moved to the front of the bike to be as close as possible to the motor. This also enables the design to be mounted on the bike without modifying the frame. The concept is taken from idea to materialized product through a fish trap process. During the materialisation, a functional prototype is build to test the set up with two 18V batteries and the working of a new lock system. The fish trap process results in a material concept, in which the different components and their assembly are established.Integrated Product Desig
Archaeology and Ethnicity: Avars, Caranths and Moravians in the 8th Century
No full textThe author poses the question as to whether or not it is possible to draw conclusions about the ethnic consciousness of the Avars on the basis of archaeological findings from the 8th century. As currently used in the historical and social science literature the term ,ethnicity\u27 usually refers to communities who differentiate themselves from other groups in terms of their language, history, origins, religion, dress, material culture etc., and who create a sense of belonging together from that consciousness. The author outlines the present state of knowledge about the Avars, which is predominantly based on the results of excavations of Avar burial sites. Avarian culture emerged in the Carpathian basin from the 6th century onwards at a point where the byzantine culture of the east came into contact with the bavarian-frankish culture to the west. However, owing to the fact that most of our knowledge of the Avars\u27 culture is based upon fragmentary material evidence - nothing of their oral traditions has survived - it is very difficult to come to any firm conclusions as to their sense of ethnicity.The author poses the question as to whether or not it is possible to draw conclusions about the ethnic consciousness of the Avars on the basis of archaeological findings from the 8th century. As currently used in the historical and social science literature the term ,ethnicity\u27 usually refers to communities who differentiate themselves from other groups in terms of their language, history, origins, religion, dress, material culture etc., and who create a sense of belonging together from that consciousness. The author outlines the present state of knowledge about the Avars, which is predominantly based on the results of excavations of Avar burial sites. Avarian culture emerged in the Carpathian basin from the 6th century onwards at a point where the byzantine culture of the east came into contact with the bavarian-frankish culture to the west. However, owing to the fact that most of our knowledge of the Avars\u27 culture is based upon fragmentary material evidence - nothing of their oral traditions has survived - it is very difficult to come to any firm conclusions as to their sense of ethnicity
