Who am I talking with? A face memory for social robots

In order to provide personalized services and to develop human-like interaction capabilities robots need to rec- ognize their human partner. Face recognition has been studied in the past decade exhaustively in the context of security systems and with significant progress on huge datasets. However, these capabilities are not in focus when it comes to social interaction situations. Humans are able to remember people seen for a short moment in time and apply this knowledge directly in their engagement in conversation. In order to equip a robot with capabilities to recall human interlocutors and to provide user- aware services, we adopt human-human interaction schemes to propose a face memory on the basis of active appearance models integrated with the active memory architecture. This paper presents the concept of the interactive face memory, the applied recognition algorithms, and their embedding into the robot’s system architecture. Performance measures are discussed for general face databases as well as scenario-specific datasets

Regularization methods for finding the relaxation time spectra of linear polydisperse polymer melts

The calculation of discrete or continuous relaxation time spectra from rheometric measurables of polydisperse polymers is an ill-posed problem. In this paper, a curve fitting method for solving this problem is presented and compared to selected models from the literature. It is shown that the new method is capable of correctly predicting the molecular mass distributions of linear polydisperse polymer melts as well as their relaxation time spectra

Degeneracy of vector-channel spatial correlators in high temperature QCD

We study spatial isovector meson correlators in $N_f=2$ QCD with dynamical domain-wall fermions on $32^3\times 8$ lattices at temperatures up to 380 MeV with various quark masses. We measure the correlators of spin-one isovector operators including vector, axial-vector, tensor and axial-tensor. At temperatures above $T_c$ we observe an approximate degeneracy of the correlators in these channels, which is unexpected because some of them are not related under $SU(2)_L \times SU(2)_R$ nor $U(1)_A$ symmetries. The observed approximate degeneracy suggests emergent $SU(2)_{CS}$ (chiral-spin) and $SU(4)$ symmetries at high $T$.Comment: 8 pages, 2 tables, 4 figures. Talk presented at the 35th International Symposium on Lattice Field Theory, 18-24 June 2017, Granada, Spain. arXiv admin note: substantial text overlap with arXiv:1707.0188

Impact of VAT Exemptions in the Postal Sector on Competition and Welfare

The focus of our paper is on the competitive effects of the proposed VAT regime relative to selected alternatives. We also highlight the welfare effects of various VAT scenarios. While an exempt operator cannot reclaim VAT paid on inputs (relevant for non-labor inputs only) and therefore faces higher costs ceteris paribus, an important fraction of customers of non-exempt operators will not be able to deduct VAT themselves. Hence, the exempt incumbent operator has on the one hand a cost disadvantage, and on the other, a price advantage. The net effect will depend on the fraction of non-labor inputs relative to the fraction of non-rated customers. We report market shares, optimum prices, tax revenue and welfare in a liberalized postal market. The various scenarios differ by the operators’ VAT status. We also take into account the fraction of non-rated customers that cannot deduct VAT themselves. The paper sheds light on the main competitive impact of VAT policies while showing the consequences on overall welfare. We show that the results are very sensitive to the operators’ labor policies. Consequently, VAT exemptions have a different impact in countries with different labor regulations. The comprehensive treatment of competition and welfare enables us to provide guidance on how to resolve the policy trade-off between consumer surplus, government tax revenue, and a level playing field in liberalized postal markets.Value Added Taxation, Regulation, Post, Competition, Welfare