49 research outputs found

    The hidden majority/minority consensus: Minorities show similar preference patterns of immigrant support as the majority population

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    The acceptance of new arrivals has become an important topic regarding the social cohesion of the receiving countries. However, previous studies focused only on the native population's drivers of attitudes towards immigrants, disregarding that immigrant-origin inhabitants now form a considerable part of the population. To test whether the drivers for the willingness to support immigrants are the same for natives and immigrants and their descendants, we rely on a vignette study conducted in a representative German online panel (N = 3149) which contains an overrepresentation of immigrant-origin respondents. We presented participants with three vignettes of potential immigrants, varying, amongst other factors, economic prospects, safe and war-ridden countries of origin (to capture deservingness), as well as religious identity. While we find that minority members are generally slightly more welcoming towards immigrants than majority members, at their core are the same factors that drive attitudes to immigrants in both groups: economic cost, cultural similarity, and deservingness. However, we observe differences at the margins: Immigrant-origin respondents take into account economic prospects to a lesser degree than majority members do, and by trend, they are less likely to distinguish between immigrants from war-ridden and safe countries of origin. Furthermore, we can show that the preference for immigrants with the same religious identities not only occurs among majority members but also among minority members

    Process Oriented Collaboration in Grid-Environments: A Case Study in the Construction Industry

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    This paper addresses the process-oriented collaboration based on a grid-based platform for the support of virtual organizations (VO), illustrated on the example of the construction industry. Distributed, organizational and IT-structures of teams involved in vintage complex projects cannot be managed with conventional methods in an appropriate manner. Both using a grid platform and grid-based services, in conjunction with semantic methods for consistency saving and goal-oriented process management can increase the efficiency of collaboration processes in large-scale projects. A hybrid grid- and web service-based architecture for the next generation of VO service and a gateway solution was developed integrating the process-oriented perspective and prototypically implemented. The problem, as well as the solution on the basis of the hybrid system architecture combing the benefits of the cutting-edge technologies, the methodical concept for modeling VO processes and their automated execution on a grid platform are discussed in detail

    Deformation twins as a probe for tribologically induced stress states

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    Friction and wear of metals are critically influenced by the microstructures of the bodies constituting the tribological contact. Understanding the microstructural evolution taking place over the lifetime of a tribological system therefore is crucial for strategically designing tribological systems with tailored friction and wear properties. Here, we focus on single-crystalline CoCrFeMnNi that is prone to form twins at room temperature. Deformation twins feature a pronounced orientation dependence with a tension-compression anisotropy, a distinct strain release in an extended volume and robust onset stresses. This makes deformation twinning an ideal probe to experimentally investigate the complex stress fields occurring in a tribological contact. Our results clearly show a grain orientation dependence of twinning under tribological load. Unexpectedly, neither the crystal direction parallel to the sliding nor the normal direction are solely decisive for twinning. This experimental approach is ideal to experimentally validate tribological stress field models, as is demonstrates here

    Dislocation-mediated and twinning-induced plasticity of CoCrFeMnNi in varying tribological loading scenarios

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    Coarse-grained, metallic materials undergo microstructure refinement during tribological loading. This in turn results in changing tribological properties, so understanding deformation under tribological load is mandatory when designing tribological systems. Single-trace experiments were conducted to understand the initiation of deformation mechanisms acting in various tribological systems. The main scope of this work was to investigate the influence of normal and friction forces as well as crystal orientations on the dominating deformation mechanism in a face-centred cubic concentrated solid solution. While varying the normal force is easily realised, varying friction forces were achieved by using several counter body materials paired against CoCrFeMnNi. The subsurface deformation layer was either mediated through dislocation slip or twinning, depending on the grain orientation and on the tribological system. A layer dominated by dislocation-based deformation is characterised by lattice rotation, the formation of a dislocation trace line or subgrain formation. Such behaviour is observed for tribological systems with a low friction coefficient. For systems dominated by deformation twinning, three types of twin appearance were observed: small twins interacting with the surface, large twins and grains with two active twin systems. Two different twinning mechanisms are discussed as responsible for these characteristics

    Conditions for equality of hulls in the calculus of variations

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    We simplify and sharpen several results by K. Zhang concerning properties of quasiconvex hulls of sets and quasiconvex envelopes of their distance functions. The approach emphasizes the underlying geometry and in particular we show that Kpc = Kc implies Krc = Kc if and only if min{m, n} ≦ 2 thus answering a question raised in [Z2]
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