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Aufsatz
Does backyard-keeping of native sows by smallholders in Quezon, Philippines, offer sustainability benefits compared to more intensive management of exotic sow breeds?
(2020-04-03)
The present study in Quezon, Philippines, assessed the sustainability of small-scale production systems, based either on native or on exotic sow breeds, using different survey tools in a socio-economic approach. In two research periods, data sets with 49 households and 68 households, respectively, all smallholder farmers keeping ≤5 sows, were compiled. In 2016, four municipalities were purposively selected, each representing one of Quezon’s four districts. In 2017, two municipalities, both with larger populations of ...
Aufsatz
Parameter identification of crack-like notches in aluminum plates based on strain gauge data
(2020-12-31)
The identification of crack parameters and stress intensity factors in aluminum plates under tensile loading is in the focus of the presented research. In this regard, data of strain gauges, distributed along the edges of the samples, are interpreted. In the experiments, slit-shaped notches take the role of cracks located in the interior of the specimens. Their positions, inclinations and lengths as well as the magnitudes of external loadings are identified solving the inverse problems of cracked plates and associated ...
Aufsatz
Quenching of High Entropy Alloys after Annealing
(2020)
The effect of cooling rate after annealing at 900 °C on the microstructure and hardness of high entropy alloys was investigated using two typical samples with the chemical composition of Co₁₆Cr₁₄.₅Fe₂₉Mn₁₁.₅Ni₂₉ and Co₁₁.₅Cr₇Fe₂₇Mn₂₇Ni₂₇(Nb₀.₀₈C₀.₅) (at%). The microstructural characterisation and hardness measurements were carried out by optical microscopy, scanning electron microscopy, wavelength-dispersive X-ray spectroscopy, electron back scattered diffraction, X-ray diffraction technique and Vickers hardness ...
Aufsatz
Are farmer perceptions among significant determinants of adoption of agricultural diversity in Malawi? A case of Lilongwe district
(2020-12-14)
Agricultural diversity can strengthen resilience of livelihood of farmers to climate change and market uncertainties while, potentially at the same time, o ering better dietary and nutritional prospects for households. Adoption of agricultural diversity in Malawi is low. Policy-makers, researchers, non-governmental organisations (NGOs), and extension staff need to understand dynamics of adoption of agricultural diversity in order to develop appropriate policies and interventions to promote agricultural diversification. ...
Aufsatz
Effect of Grain Statistics on Micromechanical Modeling: The Example of Additively Manufactured Materials Examined by Electron Backscatter Diffraction
(2020-02-21)
Micromechanical modeling is one of the prominent numerical tools for the prediction of mechanical properties and the understanding of deformation mechanisms of metals. As input parameters, it uses data obtained from microstructure characterization techniques, among which the electron backscatter diffraction (EBSD) technique allows us to understand the nature of microstructural features, that are usually described by statistics. Because of these advantages, the EBSD dataset is widely used for synthetic microstructure ...
Aufsatz
Effect of Tool Temperature on Mechanical Properties and Microstructure of Thermo-Mechanically Processed AA6082 and AA7075 Aluminum Alloys
(2020-06-08)
The present work focuses on the effect of thermo-mechanical processing on the mechanical properties and microstructural evolution of AA6082 and AA7075 aluminum alloys using a novel forming process, i. e. integrating solution heat treatment, hot forming and tool quenching. Different tool temperatures ranging from 24 °C to 350 °C were applied to investigate their influence on mechanical strength and ductility. By using various tool temperatures, this study aims to provide insights needed for tailoring the mechanical ...
Aufsatz
Effect of Friction Stir Processing on Microstructural, Mechanical, and Corrosion Properties of Al-Si12 Additive Manufactured Components
(2020-01-03)
Additive manufacturing (AM) is an advanced manufacturing process that provides the opportunity to build geometrically complex and highly individualized lightweight structures. Despite its many advantages, additively manufactured components suffer from poor surface quality. To
locally improve the surface quality and homogenize the microstructure, friction stir processing (FSP) technique was applied on Al-Si12 components produced by selective laser melting (SLM) using two different working media. The effect of FSP on ...
Aufsatz
Influence of complex geometries on the properties of laser-hardened surfaces
(2020-04-25)
Laser surface hardening provides for many advantages in terms of flexible production due to very localized and controlled energy input into the material. Laser processing offers the possibility to treat surfaces in order to locally strengthen the areas that are prone to fatigue cracking. It is well known that laser energy absorption depends on many parameters, e.g., the surface structure and the surface orientation. The incident angle of the laser beam plays a key role in this regard. When complex geometries like ...
Aufsatz
Excellent superelasticity in a Co-Ni-Ga high-temperature shape memory alloy processed by directed energy deposition
(2020-04-30)
A Co-Ni-Ga high-temperature shape memory alloy has been additively manufactured by directed energy deposition. Due to the highly anisotropic microstructure, i.e. columnar grains featuring a strong near-⟨001⟩ texture in build direction, the as-built material is characterized by a very low degree of constraints and, thus, shows excellent superelasticity without conducting a post-process heat treatment. As characterized by in situ deformation testing and post-mortem microstructural analysis, additive manufacturing ...
Aufsatz
Effect of Village Savings and Loan Associations on adoption of index-based crop insurance under limited liabilities
(2020-03-26)
A household survey and focus group discussions were conducted to quantify the general determinants of an index-based crop insurance adoption under limited liabilities in Burundi, and specifically the effect of existing Village Savings and Loan Associations (VSLAs). The survey sample comprised of 40 crop insurance adopters, 40 non-adopters and 40 drop-outs in Bukirasazi and Makebuko communes of Gitega province.
The results indicated that saving money (by VSLAs) for upcoming premium payments and regularly VSLA meetings ...