199 research outputs found

    White lies

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    In this paper we distinguish between two types of white lies: those that help others at the expense of the person telling the lie, which we term altruistic white lies, and those that help both others and the liar, which we term Pareto white lies. We find that a large fraction of participants are reluctant to tell even a Pareto white lie, demonstrating a pure lie aversion independent of any social preferences for outcomes. In contrast, a nonnegligible fraction of participants are willing to tell an altruistic white lie that hurts them a bit but significantly helps others. Comparing white lies to those where lying increases the liar's payoff at the expense of another reveals important insights into the interaction of incentives, lying aversion, and preferences for payoff distributions. Finally, in line with previous findings, women are less likely to lie when it is costly to the other side. Interestingly though, we find that women are more likely to tell an altruistic lie

    An electron hole doping and soft x-ray spectroscopy study on La1-xSrxFe0.75Ni0.25O3-{\delta}

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    The conductivity of the electron hole and polaron conductor La1-xSrxFe0.75Ni0.25O3-{\delta}, a potential cathode material for intermediate temperature solid oxide fuel cells, was studied for 0 <x < 1 and for temperatures 300 K <T < 1250 K. In LaSrFe-oxide, an ABO3 type perovskite, A-site substitu-tion of the trivalent La3+ by the divalent Sr2+ causes oxidation of Fe3+ towards Fe4+, which forms conducting electron holes. Here we have in addition a B-site substitution by Ni. The compound for x = 0.5 is identified as the one with the highest conductivity ({\sigma} ~ 678 S/cm) and lowest activation energy for polaron conductivity (Ep = 39 meV). The evolution of the electronic structure was monitored by soft x-ray Fe and oxygen K-edge spectroscopy. Homogeneous trend for the oxida-tion state of the Fe was observed. The variation of the ambient temperature conductivity and activation energy with relative Sr content (x) shows a correlation with the ratio of (eg/eg+t2g) in Fe L3 edge up to x=0.5. The hole doping process is reflected by an almost linear trend by the variation of the pre-peaks of the oxygen K-edge soft x-ray absorption spectra

    Correlation of conductivity and angle integrated valence band photoemission characteristics in single crystal iron perovskites for 300 K < T < 800 K: Comparison of surface and bulk sensitive methods

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    A single crystal monolith of La0.9Sr0.1FeO3 and thin pulsed laser deposited film of La0.8Sr0.2Fe0.8Ni0.2O3 were subject to angle integrated valence band photoemission spectroscopy in ultra high vacuum and conductivity experiments in ambient air at temperatures from 300 K to 800 K. Except for several sputtering and annealing cycles, the specimen were not prepared in-situ.. Peculiar changes in the temperature dependent, bulk representative conductivity profile as a result of reversible phase transitions, and irreversible chemical changes are semi-quantitatively reflected by the intensity variation in the more surface representative valence band spectra near the Fermi energy. X-ray photoelectron diffraction images reflect the symmetry as expected from bulk iron perovskites. The correlation of spectral details in the valence band photoemission spectra (VB PES) and details of the conductivity during temperature variation suggest that valuable information on electronic structure and transport properties of complex materials may be obtained without in-situ preparation

    Yttrium and Hydrogen Superstructure and Correlation of Lattice Expansion and Proton Conductivity in the BaZr0.9Y0.1O2.95 Proton Conductor

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    Bragg reflections in Y-resonant x-ray diffractograms of BaZr0.9Y0.1O2.95 (BZY10) reveal that Y is organized in a superstructure. Comparison with neutron diffraction superstructure reflections in protonated/deuterated BZY10 suggests that both superstructures are linked, and that protons move in the landscape imposed by the Y. The thermal lattice expansion decreases abruptly for protonated BZY10 at T≥648±20 K, coinciding with the onset of lateral proton diffusion and suggesting a correlation of structural changes and proton conductivity. The chemical shift in the Y L1-shell x-ray absorption spectra reveals a reduction from Y3+ toward Y2+ upon protonation

    Correlation of high temperature X-ray photoemission spectral features and conductivity of epitaxially strained (La0.8Sr0.2)0.95Ni0.2Fe0.8O3/SrTiO3(110)

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    Reversible and irreversible discontinuities at around 573 K and 823 K in the electric conductivity of a strained 175 nm thin film of (La0.8Sr0.2)0.95Ni0.2Fe0.8O3-{\delta} grown by pulsed laser deposition on SrTiO3 (110) are reflected by valence band changes as monitored in photoemission and oxygen K-edge x-ray absorption spectra. The irreversible jump at 823 K is attributed to depletion of doped electron holes and reduction of Fe4+ to Fe3+, as evidenced by oxygen and iron core level soft x-ray spectroscopy, and possibly of a chemical origin, whereas the reversible jump at 573 K possibly originates from structural changes

    Entanglement of charge transfer, hole doping, exchange interaction and octahedron tilting angle and their influence on the conductivity of La1-xSrxFe0.75Ni0.25O3-{\delta}: A combination of x-ray spectroscopy and diffraction

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    Substitution of La by Sr in the 25% Ni doped charge transfer insulator LaFeO3 creates structural changes that inflect the electrical conductivity caused by small polaron hopping via exchange interactions and charge transfer. The substitution forms electron holes and a structural crossover from orthorhombic to rhombohedral symmetry, and then to cubic symmetry. The structural crossover is accompanied by a crossover from Fe3+-O2--Fe3+ superexchange interaction to Fe3+-O2--Fe4+ double exchange interaction, as evidenced by a considerable increase of conductivity. These interactions and charge transfer mechanism depend on superexchange angle, which approaches 180{\deg} upon increasing Sr concentration, leading an increased overlap between the O (2p) and Fe/Ni (3d) orbitals

    Testing in the incremental design and development of complex products

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    Testing is an important aspect of design and development which consumes significant time and resource in many companies. However, it has received less research attention than many other activities in product development, and especially, very few publications report empirical studies of engineering testing. Such studies are needed to establish the importance of testing and inform the development of pragmatic support methods. This paper combines insights from literature study with findings from three empirical studies of testing. The case studies concern incrementally developed complex products in the automotive domain. A description of testing practice as observed in these studies is provided, confirming that testing activities are used for multiple purposes depending on the context, and are intertwined with design from start to finish of the development process, not done after it as many models depict. Descriptive process models are developed to indicate some of the key insights, and opportunities for further research are suggested

    Innovation and Crowdsourcing Contests

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    In an innovation contest, an organizer seeks solutions to an innovation-related problem from a group of independent agents. Agents, who can be heterogeneous in their ability levels, exert efforts to improve their solutions, and their solution qualities are uncertain due to the innovation and evaluation processes. In this chapter, we present a general model framework that captures main features of a contest, and encompasses several existing models in the literature. Using this framework, we analyze two important decisions of the organizer: a set of awards that will be distributed to agents and whether to restrict entry to a contest or to run an open contest. We provide a taxonomy of contest literature, and discuss past and current research on innovation contests as well as a set of exciting future research directions
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