In the Laboratory of Communications and Telematics (LCT) of the University of Coimbra researchers have developed a novel, adaptive class-based QoS framework (LCT-QoS). In contrast to common, static resource allocation the core concept behind this approach is a dynamic resource distribution based on delay and loss measurements. As a further step towards a complete framework, currently research i...

Following an earlier work we derive a gauge-independent canonical structure for a fully relativistic multicomponent plasma theory. The Klimontovich form of the distribution function is used to derive the basic Poisson bracket relations for the canonical variables/~, B, and E. The Poisson bracket relations provide an explicit canonical realization of the Lie algebra of the Poincar6 group and the...

It is shown that in the modified axial gauge version of canonically quantized QCD3+1 on a torus only nongeneric gauge field configurations allow for large gauge transformations. For the other configurations, the gauge is fixed completely. Such configurations carry nonzero total magnetic abelian fluxes, correspond to magnetic vortices parallel to the coordinate axes and are incorporated using bo...

The notion of a multiplier of a group X is generalized to that of a C-multiplier by allowing it to have values in an arbitrary C-algebra A. On the other hand, the notion of the action of X in A is generalized to that of a projective action of X as linear transformations of the space of continuous functions with compact support in X and with values in A. It is shown that there exists a one-to-on...

In this paper, we generalize the linear canonical transform (LCT) to quaternion-valued signals, known as the quaternionic linear canonical transform (QLCT). Using the properties of the LCT we establish an uncertainty principle for the QLCT. This uncertainty principle prescribes a lower bound on the product of the effective widths of quaternion-valued signals in the spatial and frequency domains...

Driver errors related to visual and cognitive distraction were studied in the context of the Lane Change Test (LCT). New performance metrics were developed in order to capture the specific effects of visual and cognitive distraction. In line with previous research, it was found that the two types of distraction impaired driving in different ways. Visual, but not cognitive, distraction led to re...

We propose a SUSY variant of the action for a massless spinning particles via the inclusion of twistor variables. The action is constructed to be invariant under SUSY transformations and τ -reparametrizations even when an interaction field is including. The constraint analysis is achieved and the equations of motion are derived. The commutation relations obtained for the commuting spinor variab...

Linear canonical transforms (LCTs) are a family of integral transforms with wide application in optical, acoustical, electromagnetic, and other wave propagation problems. The Fourier and fractional Fourier transforms are special cases of LCTs. In this paper, we extend the uncertainty principle for hypercomplex signals in the linear canonical transform domains, giving the tighter lower bound on ...

We show that the Kähler-Ricci flow on an algebraic manifold of positive Kodaira dimension and semi-ample canonical line bundle converges to a unique canonical metric on its canonical model. It is also shown that there exists a canonical measure of analytic Zariski decomposition on an algebraic manifold of positive Kodaira dimension. Such a canonical measure is unique and invariant under biratio...

This paper describes a technique for information mediation when multiple heterogeneous knowledge and data servers are to be accessed during query processing. One problem is building an intelligent interface between each knowledge server (KS) and its processor (KP); and the second is to provide interoper-ability among multiple KP/KS so that a query may be answered using information from multiple...