7,106 research outputs found
Risk aversion and bidding theory
Theory of bidding behavior and formation of bidding model with risk aversio
Low density expansion and isospin dependence of nuclear energy functional: comparison between relativistic and Skyrme models
In the present work we take the non relativistic limit of relativistic models
and compare the obtained functionals with the usual Skyrme parametrization.
Relativistic models with both constant couplings and with density dependent
couplings are considered. While some models present very good results already
at the lowest order in the density, models with non-linear terms only reproduce
the energy functional if higher order terms are taken into account in the
expansion.Comment: 16 pages,6 figures,5 table
Spin g-factor due to electronic interactions in graphene
The gyromagnetic factor is an important physical quantity relating the
magnetic-dipole moment of a particle to its spin. The electron spin g-factor in
vacuo is one of the best model-based theoretical predictions ever made, showing
agreement with the measured value up to ten parts per trillion. However, for
electrons in a material the g-factor is modified with respect to its value in
vacuo because of environment interactions. Here, we show how interaction
effects lead to the spin g-factor correction in graphene by considering the
full electromagnetic interaction in the framework of pseudo-QED. We compare our
theoretical prediction with experiments performed on graphene deposited on SiO2
and SiC, and we find a very good agreement between them.Comment: Improved version of the manuscript; valley g-factor part has been
remove
Light clusters and the pasta phase
The effects of including light clusters in nuclear matter at low densities
are investigated within four different parametrizations of relativistic models
at finite temperature. Both homogeneous and inhomogeneous matter (pasta phase)
are described for neutral nuclear matter with fixed proton fractions. We
discuss the effect of the density dependence of the symmetry energy, the
temperature and the proton fraction on the non-homogeneous matter forming the
inner crust of proto-neutron stars. It is shown that the number of nucleons in
the clusters, the cluster proton fraction and the sizes of the Wigner Seitz
cell and of the cluster are very sensitive to the density dependence of the
symmetry energy.Comment: 14 pages, 14 figures; Accepted for publication in Phys. Rev.
How costumers' way of life influence the value co-creation
Purpose: This article is a contribution to the understanding of how value arises in well-established markets, and under which circumstances actors integrate resources from different service ecosystems to generate value. To understand this phenomenon, it is fundamental to consider which practices are performed by customers to co-create value and how they do so. Design/Methodology/Approach: Using a qualitative approach, the study provides fresh empirical insight into well-established market processes of value creation. After a literature review an ethnographic approach was chosen in order to understand how co-creation processes occur in the empirical setting of an international restaurant chain. Several observations, conversations and semi-structured interviews were undertaken concerning the analysis of the topic under study. Findings: The results show that even in a well-established market, a provider must consider individual customers’ distinct needs, present in their daily practices, to be able to assist them in the value creation process. It is argued that the practice styles are the building blocks for prevailing ways of life that actors assume, according to the context in which they are, to integrate resources. Practical implications: The study includes implications for service providers of a well-founded market for facilitating value co-creation along with customers and fulfils the need to better understand this phenomenon. Originality/Value: Recent studies call for empirical evidence on co-creation processes in mature markets, accordingly, this study brings an additional understanding on how actors, depending on the context, adopt different ways of life that require unique resources, which activate to achieve what they want, in order to establish room for co-creation.info:eu-repo/semantics/publishedVersio
Valor de uso num contexto B2B na logÃstica no sector alimentar
The main objective of this research is to understand the way a provider participates and contributes in the value co-creation process and identify the drivers that contribute to it. Given the nature of the phenomena under study a qualitative research approach was chosen to conduct this study. To reach a deep understanding about the phenomena in the B2B empirical context where it takes place, a case study was conducted and data was collected through semi-structured interviews to key informants involved in the process. A link between value-in-use dimensions emerged suggesting the importance to the logistic provider to adapt its operation and internal organization in order to better contribute to the value creation process. The mechanisms that influence the experience lived by the logistic provider’s customer were identified and point to the importance of interactions and building a strong relationship in order to create a trust and collaborative environment between companies.info:eu-repo/semantics/publishedVersio
Collective modes in relativistic npe matter at finite temperature
Isospin and density waves in neutral neutron-proton-electron (npe) matter are
studied within a relativistic mean-field hadron model at finite temperature
with the inclusion of the electromagnetic field. The dispersion relation is
calculated and the collective modes are obtained. The unstable modes are
discussed and the spinodals, which separate the stable from the unstable
regions, are shown for different values of the momentum transfer at various
temperatures. The critical temperatures are compared with the ones obtained in
a system without electrons. The largest critical temperature, 12.39 MeV, occurs
for a proton fraction y_p=0.47. For y_p=0.3 we get =5 MeV and for
y_p>0.495 MeV.
It is shown that at finite temperature the distillation effect in asymmetric
matter is not so efficient and that electron effects are particularly important
for small momentum transfers.Comment: 10 pages, 6 figure
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