Angels with dirty faces: punk, moda e iconoclastias contemporâneas

Fair Exchange with Guardian Angels

In this paper we propose a new probabilistic Fair Exchange Protocol which requires no central Trusted Third Party. Instead, it relies on a virtually distributed and decentralized Trusted Third Party which is formalized as a Guardian Angel: a kind of Observer e.g. a tamper proof security device. We thus introduce a network model with Pirates and Guardian Angels which is well suited for Ad Hoc ne...

Angels and Other Servants

In politics as in history, masters accomplish great things, but often, lowly beings such as servants perform those tasks. At times, they subvert them. In science, servant-beings are frequently described as demons and angels. Who are these effective agents? This essay traces parts of the large historical network of persons and places in which ‘little helpers’ service their master’s will. It look...

Distributional Dominance with Dirty Data

Distributional dominance criteria are commonly applied to draw welfare inferences about comparisons, but conclusions drawn from empirical implementations of dominance criteria may be inßuenced by data contamination. We examine a non-parametric approach to reÞning Lorenz-type comparisons and apply the technique to two important examples from the LIS data-base. ¤

Liveness detection using cross-moda person authent

In this paper we show the potential of two new features as powerful anti-spoofing measures for face-voice person authentication systems. The features based on latent semantic analysis (LSA) and canonical correlation analysis (CCA), enhance the performance of the authentication system in terms of better anti-imposture abilities and guard against video replay attacks, which is a challenging type ...

Angels Without Wings