Inferring eye movements on the basis of head and visual target position

The modern optical lens design process relies on ray-tracing that requires the geometry of the visual task to be simulated in order to derive the optical parameters. Such measurements must take into account distant, intermediate and near visual tasks. SOLA has developed a non-intrusive, low cost system which tracks eye movements during the reading process. This report analyses their procedure in order to determine the accuracy of the tracking system. It concludes that some assumptions in the existing algorithm are overly restrictive, while, overall, this is an effective tracking method. In addition, a Fourier analysis of the sampling rate demonstrates that 10 Hz is a sufficiently high rate to use, and that lossy compression is adequate for their needs

Dealing with rogue virtual machines in a cloud services environment

In current cloud services hosting solutions, various mechanisms have been developed to minimize the possibility of hosting staff from breaching security. However, while functions such as replicating and moving machines are legitimate actions in clouds, we show that there are risks in administrators being able to perform them. We describe three threat scenarios related to hosting staff on the cloud architecture and indicate how an appropriate accountability architecture can mitigate these risks in the sense that the attacks can be detected and the perpetrators identified. We identify requirements and future research and development needed to protect cloud service environments from these attacks

Multi-Line Geometry of Qubit-Qutrit and Higher-Order Pauli Operators

The commutation relations of the generalized Pauli operators of a qubit-qutrit system are discussed in the newly established graph-theoretic and finite-geometrical settings. The dual of the Pauli graph of this system is found to be isomorphic to the projective line over the product ring Z2xZ3. A "peculiar" feature in comparison with two-qubits is that two distinct points/operators can be joined by more than one line. The multi-line property is shown to be also present in the graphs/geometries characterizing two-qutrit and three-qubit Pauli operators' space and surmised to be exhibited by any other higher-level quantum system.Comment: 8 pages, 6 figures. International Journal of Theoretical Physics (2007) accept\'

A Survey of Finite Algebraic Geometrical Structures Underlying Mutually Unbiased Quantum Measurements

The basic methods of constructing the sets of mutually unbiased bases in the Hilbert space of an arbitrary finite dimension are discussed and an emerging link between them is outlined. It is shown that these methods employ a wide range of important mathematical concepts like, e.g., Fourier transforms, Galois fields and rings, finite and related projective geometries, and entanglement, to mention a few. Some applications of the theory to quantum information tasks are also mentioned.Comment: 20 pages, 1 figure to appear in Foundations of Physics, Nov. 2006 two more references adde

Cryptographic public key length prediction

In the late 1900s, suitable key lengths were determined by cryptographers who considered four main features based on implementation, expected lifespan and associated security. By 2010, recommendations are aimed at governmental and commercial institutions, which take into consideration practical implementations that provide data security. By aggregating the key length predictive data since 1985, we notice that while the figures proposed between 1990 and 2010 increase linearly, those proposed for 2010 to 2050 do not. This motivates us to re-think the factors used as a basis for key length predictions and we initiate this re-evaluation in this paper. Focusing first on implementation, we clarify the meaning of Moore’s Law by going back to his original papers and commentary. We then focus on the period 2010-2015, when non-linearity appears, and test Moore’s Law based on three different hardware platforms. Our conclusion is that current assumptions about Moore’s law are still reasonable and that non-linearity is likely to be caused by other factors which we will investigate in future work