The hyperbolic lattice point problem in conjugacy classes

For Γ a cocompact or cofinite Fuchsian group, we study the hyperbolic lattice point problem in conjugacy classes, which is a modification of the classical hyperbolic lattice point problem. We use large sieve inequalities for the Riemann surfaces Γ∖ℍ to obtain average results for the error term, which are conjecturally optimal. We give a new proof of the error bound O(X2/3), due to Good. For SL2(ℤ) we interpret our results in terms of indefinite quadratic forms

Environmental Management and Corporate Social Responsibility Practices of Small and Medium-sized Enterprises

The main aim of this paper is to facilitate small and medium sized enterprises (SMEs) to adopt environmental management (EM) and corporate social responsibility (CSR) practices. The study reveals SMEs‟ motivation, pressure, targets and methods for EM and CSR practices. Additionally, the paper investigates how these variables relate to employee number, turnover and geographical locations. The outcomes of the research will add value to SMEs decision-making processes in both strategic and policy levels (e.g. supplier selection) and policymakers‟ initiatives to make SMEs environment and socially friendly. Although there are studies on EM and CSR practices of SMEs, they mainly focus on impact of EM and CSR practices on business performance, and SMEs‟ motivation for adopting EM and CSR practices in specific country. Studies that reveal SMEs‟ motivation, pressure, targets and methods for EM and CSR practices and their relationship with their characteristics (e.g. size, turn over, and geographical location) are scant. This research bridges this gap. Our data originates from 223 carefully selected representative SMEs in the West Midlands, UK (105) and Kolkata, India (118) covering manufacturing and process industries. The relevant data was collected using questionnaires and analysed using Analysis of Variance (ANOVA) and Multivariate Analysis of Variance (MANOVA) methods. The results reveal that perceptions of SMEs‟ motivation, pressure, targets and methods of EM and CSR practices vary considerably with respect to size, turn over and geographical location. The findings are significant to policymakers, client organizations and individual SME for improving EM and CSR practices

Visual-only recognition of normal, whispered and silent speech

Silent speech interfaces have been recently proposed as a way to enable communication when the acoustic signal is not available. This introduces the need to build visual speech recognition systems for silent and whispered speech. However, almost all the recently proposed systems have been trained on vocalised data only. This is in contrast with evidence in the literature which suggests that lip movements change depending on the speech mode. In this work, we introduce a new audiovisual database which is publicly available and contains normal, whispered and silent speech. To the best of our knowledge, this is the first study which investigates the differences between the three speech modes using the visual modality only. We show that an absolute decrease in classification rate of up to 3.7% is observed when training and testing on normal and whispered, respectively, and vice versa. An even higher decrease of up to 8.5% is reported when the models are tested on silent speech. This reveals that there are indeed visual differences between the 3 speech modes and the common assumption that vocalized training data can be used directly to train a silent speech recognition system may not be true

An engine selection methodology for high fidelity serious games

Serious games represent the state-of-the-art in the convergence of electronic gaming technologies with instructional design principles and pedagogies. Whilst the selection criteria for entertainment game engines are often transparent, due to the range of available platforms and engines an emerging challenge is the choice of platform for serious games, whose selection often has substantially different objectives and technical requirements depending upon context and usage. Additionally, the convergence of training simulations with serious gaming, made possible by increasing hardware rendering capacity, is enabling the creation of high-fidelity serious games which challenge existing design and instructional approaches. This paper highlights some of the differences between the technical requisites of high-fidelity serious and leisure games, and proposes a selection methodology based upon these emergent characteristics. The case study of part of a high-fidelity model of Ancient Rome is used to compare aspects of the four different game engines according to elements defined in the proposed methodology

Nematic-Isotropic Transition with Quenched Disorder

Nematic elastomers do not show the discontinuous, first-order, phase transition that the Landau-De Gennes mean field theory predicts for a quadrupolar ordering in 3D. We attribute this behavior to the presence of network crosslinks, which act as sources of quenched orientational disorder. We show that the addition of weak random anisotropy results in a singular renormalization of the Landau-De Gennes expression, adding an energy term proportional to the inverse quartic power of order parameter Q. This reduces the first-order discontinuity in Q. For sufficiently high disorder strength the jump disappears altogether and the phase transition becomes continuous, in some ways resembling the supercritical transitions in external field.Comment: 12 pages, 4 figures, to be published on PR

Can one hear the shape of the Universe?

It is shown that the recent observations of NASA's explorer mission "Wilkinson Microwave Anisotropy Probe" (WMAP) hint that our Universe may possess a non-trivial topology. As an example we discuss the Picard space which is stretched out into an infinitely long horn but with finite volume.Comment: 4 page

Quenched disorder and spin-glass correlations in XY nematics

We present a theoretical study of the equilibrium ordering in a 3D XY nematic system with quenched random disorder. Within this model, treated with the replica trick and Gaussian variational method, the correlation length is obtained as a function of the local nematic order parameter and the effective disorder strength. These results clarify what happens in the limiting cases of diminishing order parameter and disorder strength, that is near a phase transition of a pure system. In particular, it is found that quenched disorder is irrelevant as the order parameter tends to zero and hence does not change the character of the continuous XY nematic to isotropic phase transition. We discuss how these results compare with experiments and simulationsComment: 19 pages, 6 figures, corrected typo