Acoustic Assessment of Twin-engined Turboprop Layout

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PROBE-GK: Predictive Robust Estimation using Generalized Kernels

Many algorithms in computer vision and robotics make strong assumptions about uncertainty, and rely on the validity of these assumptions to produce accurate and consistent state estimates. In practice, dynamic environments may degrade sensor performance in predictable ways that cannot be captured with static uncertainty parameters. In this paper, we employ fast nonparametric Bayesian inference techniques to more accurately model sensor uncertainty. By setting a prior on observation uncertainty, we derive a predictive robust estimator, and show how our model can be learned from sample images, both with and without knowledge of the motion used to generate the data. We validate our approach through Monte Carlo simulations, and report significant improvements in localization accuracy relative to a fixed noise model in several settings, including on synthetic data, the KITTI dataset, and our own experimental platform.Comment: In Proceedings of the IEEE International Conference on Robotics and Automation (ICRA'16), Stockholm, Sweden, May 16-21, 201

Detailing the Connection Between a Family of Polar Graphs and Tremain Equiangular Tight Frames

The relationship between strongly regular graphs and equiangular tight frames has been known for several years, and this relationship has been used to construct many of the most recent examples of new strongly regular graphs. In this paper, we present an explicit construction of a family of equiangular tight frames using the geometry of a quadratic space over the field of four elements. We observe that these frames give rise to a strongly regular graph on a subset of points of a quadratic space over the field with 4 elements. We then demonstrate an isomorphism between this graph and a classical construction of polar graphs. While this family of graphs is known to exist, their construction using a Tremain ETF is much simpler, requiring the existence of Steiner triple systems and Hadamard matrices of the appropriate size, whereas the original constructions require computing intersections of hyperplanes

On Zero-Sum Rado Numbers for the Equation ax_1 + x_2 = x_3

For every positive integer $a$, let $n = R_{ZS}(a)$ be the least integer, provided it exists, such that for every coloring $$\Delta : \{1, 2, ..., n\} \rightarrow \{0, 1, 2\},$$ there exist three integers $x_1, x_2, x_3$ (not necessarily distinct) such that $$\Delta(x_1) + \Delta(x_2) + \Delta(x_3) \equiv 0\ (mod\ 3)$$ and $$ax_1 +x_2 = x_3.$$ If such an integer does not exist, then $R_{ZS}(a) = \infty.$ The main results of this paper are $$R_{ZS}(2) = 12$$ and a lower bound is found for $R_{ZS}(a)$ where $a \geq 2$

Telemental Health Versus Face-to-Face Treatment: An Examination of Operation Enduring Freedom and Operation Iraqi Freedom Veterans’ Preferences for Mental Health Services

Despite high estimated prevalence rates of PTSD, depression, and alcohol use disorder, Operation Enduring Freedom and Operation Iraqi Freedom (OEF/OIF) veterans exhibit relatively low rates of engagement in mental health treatment. Research shows that OEF/OIF veterans’ treatment-seeking is affected by attitudes towards mental illness and meant health treatment, logistical barriers to care, and severity of illness, thus providing support for Andersen’s proposed model of health service utilization. Previous literature has suggested that telemental health (TMH) has the potential to address some of the factors that make treatment-seeking challenging for OEF/OIF veterans. However, little is known about the degree to which these individuals are open to TMH. This study aimed to enhance our understanding of the factors that influence OEF/OIF veterans’ treatment-seeking and to determine how these individuals view TMH in comparison to traditional face-to-face (FTF) treatment. A sample of 422 OEF/OIF veterans provided information about stigma towards mental illness, attitudes towards mental health treatment, preferences for mental health treatment, logistical barriers to care, and mental illness symptomatology. Moreover, they stated their preference between FTF treatment and TMH. Results revealed a robust preference for FTF treatment across the sample. No differences emerged between veterans preferring FTF treatment and those preferring TMH treatment across the whole sample. Notably, women veterans preferring TMH were more skeptical of treatment, had more barriers to care, and had more severe clinical symptoms. Findings indicate a clear preference for FTF treatment among OEF/OIF veterans, although some do perceive TMH as addressing stigma-related and logistical barriers to treatment

A non-perturbative study of the infra-red behaviour of QCD

The non-perturbative behaviour of the non-Abelian gauge theory of strong interactions, namely QCD, is investigated using the Schwinger-Dyson equations. Using an approximation based on solving the Slavnov-Taylor identities, we derive a closed integral equation for the full gluon propagator. We numerically solve this equation, finding a consistent solution which is as singular as 1/p(^4) the momentum p(^2) → 0, whilst at large momenta the gluon propagates like a free particle. This infra-red behaviour can be seen as a signal for the confinement of quarks and gluons, implying, for example, that the Wilson loop operator behaves an 'axea law'. We then derive an equation for the full massless quark propagator. Using our solution for the gluon, we find the quark propagator to be suppressed at low momentum, to such an extent that the physical particle pole is removed, and free quarks cannot propagate. This is just what we might expect of a confining theory. The inclusion of quarks means we must study their dynamical effects via closed fermion loops in the gluon propagator equation. This couples the two equations together. We solve the two equations simultaneously, finding that the previous infra-red behaviour still holds. As we introduce more flavours of fermions, however, the infra-red enhancement of the gluon propagator is diminished, and this in turn means that the quark propagator is less suppressed. This exhibits the dynamical importance of quarks. These physically realistic results demonstrate the importance and validity of the Schwinger-Dyson equations as a valuable tool for investigating the non-perturbative features of gauge theories

BIOMECHANICAL SERVICES AND RESEARCH FOR ATHLETES AND COACHES TO ENAHNCE PERFORMANCE AND PREVENT INJURY

Athleticism, sport-specific ability, rigorous training supervised by expert coaches and well supported daily training environments are the main determinants of success in international sporting competition (Bosscher et al., 2010). Sport Biomechanists contribute to the training environment largely by identifying and advising on movement technique. This service provides understanding of the mechanical basis of sport-specific performances and injury. However, a kinematic description of technique is often not sufficient to identify improper skill execution. Cycling presents an example where kinematic variability is low, but where underlying force application on the bicycle’s pedals and joint-specific powers during pedalling can vary. Such analyses provide a deeper understanding of potential mechanisms underlying injury and athletic performance

Age of Anxiety : Reflections on the Present State of Australian History

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