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The politics of energy landscapes: the influence of local anti-wind initiatives on state policies in Saxony, Germany
(2020-01-23)
Background
In recent years, landscapes in many countries have been transformed by efforts to fight global warming, specifically the shift towards renewable energies such as wind power. This development has been met by growing opposition from local citizens and their initiatives. There is an ongoing debate about whether and how such protests have a real impact on the development of energy landscapes.
Methods
Drawing on the rare case of a state government scaling back ambitious targets for the expansion of renewables, ...
Aufsatz
Access to the learning material enhances learning by means of generating questions: Comparing open- and closed-book conditions
(2020)
Generating questions referring to the learning material is a powerful learning strategy. The present study investigated potential mechanisms behind this effect. Students (N=231) read a text and then generated questions referring to the text in three conditions: (1) open-book (i.e., text accessible), (2) closed-book (i.e., text inaccessible), and (3) cued closed-book (i.e., text inaccessible but keywords provided). After one week, students’ knowledge gain was larger in the open-book and cued closed-book conditions ...
Aufsatz
Occurrence, distribution and alternative hosts of Wheat streak mosaic virus infecting ginger in Kaduna State, Nigeria
(2020-06-29)
A field survey was conducted during the 2018 rainy season (June – October) in three major ginger producing Local Government Areas (LGAs) of Kaduna State, Nigeria to determine the occurrence and spread of wheat streak mosaic virus (WSMV) infecting ginger. Symptomatic and asymptomatic ginger leaf samples (n=180) and weed samples (n=45) were collected from the surveyed fields and indexed against WSMV using Double Antibody Sandwich Enzyme-linked Immunosorbent Assay (DAS-ELISA). The results obtained showed that WSMV ...
Aufsatz
Typology of smallholder’s pig production systems in South Kivu, Democratic Republic of Congo: Challenges and opportunities
(2020-06-30)
Pig farming plays an important role in farmers’ livelihoods in many tropical countries. It contributes to food security of the poorest as well as the development of rural economy through multiplier effects. In the South Kivu province, pig farms are almost exclusively owned by smallholders. A few studies have attempted to describe thoroughly pig farming systems in this province. This study was undertaken to characterise pig production systems, in order to better understand their current situation, namely constraints ...
Aufsatz
On the influence of ϰ-carbides on the low-cycle fatigue behavior of high-Mn light-weight steels
(2021)
High-manganese light-weight steels offer a great potential for structural purposes in the mobility sector due to their reduced density combined with outstanding mechanical properties. As many of the envisaged applications of these materials will suffer from cyclic loading during their service life, the fundamentals of their fatigue behavior must be studied extensively. In the present work, the low-cycle fatigue (LCF) properties of an austenitic Fe-29.8Mn-7.65Al-1.11C light-weight steel were investigated. Two ...
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On the structural integrity of Fe-36Ni Invar alloy processed by selective laser melting
(2020)
Specimens made from pre-alloyed Invar (Fe-36Ni) powder were fabricated by selective laser melting and stress-relief heat treated afterwards. A relative density of the fabricated parts of 99.6 % was determined by computed tomography. The microstructure and mechanical behavior under monotonic and particularly cyclic loading at ambient temperature were investigated. Results reveal a bimodal microstructure containing columnar and equiaxed grains with an average grain size of 75 μm and pronounced texture 〈001〉 || BD. The ...
Aufsatz
Investigation of residual stresses in polypropylene using hot plate welding
(2020-08-05)
During the cooling process of the molten material, residual stresses appear because the reduced volume of the cooled material cannot fully fill the space formerly occupied by the molten material. The morphology in and around the weld is formed by different factors depending on the material and process parameters. Different morphological structures relate to different mechanical properties. The process parameters and the welding results including morphology and residual stress are linked together. In this article, ...
Aufsatz
Process Influences in the Combined Compacting and Back-Injection Process to Produce Back-Injected Self-Reinforced Composites (SRCs) – Analysis via Multiple Regression Modelling
(2021-11-21)
A new process to produce back-injected self-reinforced composites (SRCs) is presented. In contrast to other investigations on back-injection of SRCs, a process is presented which allows compacting and back injection of SRCs in one step where the SRCs are partly consolidated only via melt pressure inside the cavity. The mechanical properties of SRCs depend to a large extent on the process parameters of temperature and pressure during manufacture. These parameters are not yet known for back-injected areas. Sensors ...
Aufsatz
Ordoliberalism Out of Order? The Fragile Constitutionality of Greek Austerity (Part Two)
(2020-06)
This is the second part of a two-part post. The first part, available here, considered the historical background of the concept of constitutional order and its relation to the ordoliberal project. Judicial independence was examined in parallel with central bank independence, with each understood as a means of insulating policy from social and democratic pressures and also as a means of enacting and maintaining fiscal discipline and market-conforming order. It also included some preliminary observations on the relation ...
Aufsatz
On the low-cycle fatigue behavior of thermo-mechanically processed high-strength aluminum alloys
(2021)
In the present work low-cycle fatigue experiments were carried out on thermo-mechanically processed AA6082 and AA7075 sheets to evaluate mechanical properties under cyclic loading. Different cooling rates imposed by use of tempered forming tools after solutionizing and subsequent aging treatment led to the formation of precipitates with differing sizes and morphologies. Specimens thermo-mechanically processed in tools with temperatures of 24 °C and 200 °C showed superior mechanical properties under both monotonic and ...