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Loving the mess: navigating diversity and conflict in social values for sustainability
(2019-08-24)
This paper concludes a special feature of Sustainability Science that explores a broad range of social value theoretical traditions, such as religious studies, social psychology, indigenous knowledge, economics, sociology, and philosophy. We introduce a novel transdisciplinary conceptual framework that revolves around concepts of ‘lenses’ and ‘tensions’ to help navigate value diversity. First, we consider the notion of lenses: perspectives on value and valuation along diverse dimensions that describe what values focus ...
Aufsatz
Promoting abnormal grain growth in Fe-based shape memory alloys through compositional adjustments
(2019-05-28)
Iron-based shape memory alloys are promising candidates for large-scale structural applications due to their cost efficiency and the possibility of using conventional processing routes from the steel industry. However, recently developed alloy systems like Fe–Mn–Al–Ni suffer from low recoverability if the grains do not completely cover the sample cross-section. To overcome this issue, here we show that small amounts of titanium added to Fe–Mn–Al–Ni significantly enhance abnormal grain growth due to a considerable ...
Aufsatz
Cyclic degradation of Co49Ni21Ga30 high-temperature shape memory alloy - On the roles of dislocation activity and chemical order
(2015)
Conventional shape memory alloys (SMAs), such as binary Ni-Ti, are typically limited to service temperatures below 100 °C. Recent studies on Co-Ni-Ga high temperature (HT) SMAs revealed the potential that these alloys can be used up to temperatures of about 400 °C. Analysis of the cyclic functional properties showed that degradation in these alloys is mainly triggered by intensive dislocation motion. However, data on the cyclic stress-strain response and the mechanisms leading to functional degradation of Co-Ni-Ga ...
Aufsatz
Bend Straightening of a Carbonitrided Gear Shaft – Consequences on Residual Stresses and Retained Austenite near the Surface
(2017-06-20)
Carbonitriding of shafts in drive technology is strongly connected with distortion. Bend straightening is an important process step in order to eliminate distortion without removing the hardened surface layer. As shown in several investigations, even for simple part geometries, bending induced stresses and plastic deformations have a strong impact not only on the residual stress state but also on the microstructure after straightening. As gear shafts become increasingly filigree and complex in their geometry, the ...
Aufsatz
Climatic Ageing of Components of Polymer Based Electrochromic Devices
(2013-09-09)
Combining a shading function and a polycarbonate window displays an attractive alternative to the currently employed glass roof in vehicles. However, the ageing of such a device must be investigated before any application. Therefore, our investigations focus on the ageing of the components of a polycarbonate based electrochromic device. The optical, electrical, mechanical and electrochemical properties of the ion storage layer as well as the substrate will be assessed after storage in a climate with a high humidity ...
Aufsatz
Boxwood Borer Heterobostrychus brunneus (Coleoptera: Bostrichidae) Infesting Dried Cassava: A Current Record from Southern Ethiopia
(2017-01-27)
Insect specimens of adult beetles and larvae of 7–9 and 9–10 mm length, respectively were collected from infested dry cassava at two locations from multiple stores in southern Ethiopia. The specimens were identified as Heterobostrychus brunneus (Murray, 1867) commonly known as boxwood borer and auger beetle. The study presents a current record of H. brunneus in Ethiopia, particularly in the context of infesting food products. Additionally, a wide geographical distribution of the pest was reviewed and presented in ...
Aufsatz
Emerging Development Pathways of Urban Livestock Production in Rapidly Growing West Africa Cities
(2016-11-19)
In this study, we try to capture the degree of specialization or integration, and of intensification or extensification, of (peri-) urban livestock production, along with the factors that influence such decisions and their impact on natural resource uses. A total of 181 and 187 structured questionnaires were completed in livestock-keeping households in Ouagadougou (Burkina Faso) and Tamale (Ghana). Categorical principal component and two-step cluster analysis were used to identify homogenous groups of livestock-keeping ...
Aufsatz
Distributed practice in mathematics: Recommendable especially for students on a medium performance level?
(2019-10-24)
In this study, the effect of distributed practice on the mathematical performance of 7th graders was investigated (N == 81). After a stochastics lesson, one group of students worked three sets of exercises massed on one day, while the other group of students worked the same exercises distributed over three days. Bayesian analyses of the performance two weeks after the last practice revealed no evidence for an effect of practice condition. However, in a test after six weeks, strong evidence for a positive effect of ...
Aufsatz
Gottesliebe – Menschenliebe
(2015)
Kann menschliche Liebe in ihrer kulturellen Bedingtheit und dem Wandel unterworfen sowie in ihrer so häufig erfahrenen Brüchigkeit als Metapher für die Liebe Gottes zur Welt und zum Menschen dienen? Was könnte das konstante Element in der Liebe sein, das auch in theologischer Rede sinnvoll zeitlos gültig und dennoch menschlichen Erfahrungen angemessen von der Liebe Gottes künden kann? Diesen drängenden Fragen geht die Autorin nach und findet in der Philosophie von J. Kristeva eine Spur, die zur Theologie des Augustinus ...
Aufsatz
Crack Paths at Multiple-crack Systems in Anisotropic Simulation and Experiment
(2014-06-27)
This paper is targeted on numerical methods for accurate crack tip loading analysis and crack path prediction. Those are based on finite element calculations of the boundary value problem. Applying path-independent integrals to curved cracks in order to accurately calculate the J-integral, energy release rate (ERR) or stress intensity factors (SIF) is still not state of the art. Contours which are not confined to the crack tip require special analytical preparation and numerical treatment to supply results which are ...