Below Horizon Aircraft Detection Using Deep Learning for Vision-Based Sense and Avoid

Commercial operation of unmanned aerial vehicles (UAVs) would benefit from an onboard ability to sense and avoid (SAA) potential mid-air collision threats. In this paper we present a new approach for detection of aircraft below the horizon. We address some of the challenges faced by existing vision-based SAA methods such as detecting stationary aircraft (that have no relative motion to the background), rejecting moving ground vehicles, and simultaneous detection of multiple aircraft. We propose a multi-stage, vision-based aircraft detection system which utilises deep learning to produce candidate aircraft that we track over time. We evaluate the performance of our proposed system on real flight data where we demonstrate detection ranges comparable to the state of the art with the additional capability of detecting stationary aircraft, rejecting moving ground vehicles, and tracking multiple aircraft

Hate crime victimization in Wales: psychological and physical impacts across seven hate crime victim types

This paper presents findings from the All Wales Hate Crime Project. Most hate crime research has focused on discrete victim-types in isolation. For the first time internationally this paper examines the psychological and physical impacts of hate crime across seven victim-types drawing on quantitative and qualitative data. It contributes to the hate crime debate in two significant ways: i) it provides the first look at the problem in Wales; and ii) it provides the first multi-victim-type analysis of hate crime, showing that impacts are not homogenous across victim groups. The paper provides empirical credibility to the impacts felt by hate crime victims on the margins who as Walklate (2011) and Moran (2014) argue have routinely struggled to gain support

Insiders, Outsiders, and Involuntary Unemployment

Sexual harassment is perceived to be a major impediment to female labor force participation. We use the random assignment of U.S. federal judges setting geographically-local precedent, and the fact that judges’ biographies predict decisions in sexual harassment cases, to document the causal impact of forbidding sexual harassment. Consistent with an insider-outsider theory of involuntary unemployment, but in contrast to a mandated benefits theory of employment protections, pro-plaintiff sexual harassment precedent spurred the adoption of sexual harassment human resources policies, encouraged entry of outsiders, and reduced gender inequality in labor supply and wages among the population. These effects were comparable to the effects of the Equal Employment Opportunity Act and greatest in the construction industry, which was heavily affected by sexual harassment litigation

Insiders, Outsiders, and Involuntary Unemployment

Sexual harassment is perceived to be a major impediment to female labor force participation. We use the random assignment of U.S. federal judges setting geographically-local precedent, and the fact that judges’ biographies predict decisions in sexual harassment cases, to document the causal impact of forbidding sexual harassment. Consistent with an insider-outsider theory of involuntary unemployment, but in contrast to a mandated benefits theory of employment protections, pro-plaintiff sexual harassment precedent spurred the adoption of sexual harassment human resources policies, encouraged entry of outsiders, and reduced gender inequality in labor supply and wages among the population. These effects were comparable to the effects of the Equal Employment Opportunity Act and greatest in the construction industry, which was heavily affected by sexual harassment litigation

The first confirmation of V-type asteroids among the Mars crosser population

The Mars crossing region constitutes a path to deliver asteroids from the Inner Main Belt to the Earth crossing space. While both the Inner Main Belt and the population of Earth crossing asteroids contains a significant fraction of asteroids belonging to the V taxonomic class, only two of such V-type asteroids has been detected in the Mars crossing region up to now. In this work, we searched for asteroids belonging to the V class among the population of Mars crossing asteroids, in order to support alternative paths to the delivery of this bodies into the Earth crossing region. We selected 18 candidate V-type asteroids in the Mars crossing region using observations contained in the Sloan Digital Sky Survey Moving Objects Catalog. Then, we observed 4 of these candidates to take their visible spectra using the Southern Astrophysical Research Telescope (SOAR). We also performed the numerical simulation of the orbital evolution of the observed asteroids. We confirmed that 3 of the observed asteroids belong to the V class, and one of these may follow a path that drives it to an Earth collision in some tens of million years

Optimal Bayesian Quickest Detection for Hidden Markov Models and Structured Generalisations

In this paper we consider the problem of quickly detecting changes in hidden Markov models (HMMs) in a Bayesian setting, as well as several structured generalisations including changes in statistically periodic processes, quickest detection of a Markov process across a sensor array, quickest detection of a moving target in a sensor network and quickest change detection (QCD) in multistream data. Our main result establishes an optimal Bayesian HMM QCD rule with a threshold structure. This framework and proof techniques allow us to to elegantly establish optimal rules for several structured generalisations by showing that these problems are special cases of the Bayesian HMM QCD problem. We develop bounds to characterise the performance of our optimal rule and provide an efficient method for computing the test statistic. Finally, we examine the performance of our rule in several simulation examples and propose a technique for calculating the optimal threshold

Is perceived inability to procreate associated with life satisfaction? Evidence from a German panel study

Most studies of the psychosocial consequences of infertility have focused on those who seek medical treatment, leaving a research gap regarding the psychosocial consequences of perceived inability to procreate in the general population. Moreover, most studies are cross-sectional and the results are thus likely affected by omitted variable bias. Inspired by aspects of the Theory of Conjunctural Action, this study analysed 10 waves of data from the German Family Panel (pairfam) for women and men using fixed effects panel regression and including time-varying control variables suggested by theory and research. This study found that both women and men experienced lower life satisfaction in years when they perceived an inability to procreate. This association was not affected by the inclusion of relevant time-varying control variables. Furthermore, the association between perceived barriers to procreation and life satisfaction was found to differ depending on life circumstances and gender. Women with partners and men without partners had lower life satisfaction when they perceived an inability to procreate compared with when they did not. Women and men who intended to have a(nother) child had lower life satisfaction when they perceived an inability to procreate compared with when they did not. The association, however, was only significant for men. Somewhat surprisingly, women who perceived an inability to procreate also had lower life satisfaction when they were not intending to have a(nother) child. This study makes an important contribution to research on the psychosocial consequences of perceived infertility, and provides insights into why some people may pursue assisted reproductive technology for family creation