The FHD/ε\boldsymbol{\varepsilon}ppsilon Epoch of Reionization Power Spectrum Pipeline

Epoch of Reionization data analysis requires unprecedented levels of accuracy in radio interferometer pipelines. We have developed an imaging power spectrum analysis to meet these requirements and generate robust 21 cm EoR measurements. In this work, we build a signal path framework to mathematically describe each step in the analysis, from data reduction in the FHD package to power spectrum generation in the $\varepsilon$ppsilon package. In particular, we focus on the distinguishing characteristics of FHD/$\varepsilon$ppsilon: highly accurate spectral calibration, extensive data verification products, and end-to-end error propagation. We present our key data analysis products in detail to facilitate understanding of the prominent systematics in image-based power spectrum analyses. As a verification to our analysis, we also highlight a full-pipeline analysis simulation to demonstrate signal preservation and lack of signal loss. This careful treatment ensures that the FHD/$\varepsilon$ppsilon power spectrum pipeline can reduce radio interferometric data to produce credible 21 cm EoR measurements.Comment: 21 pages, 10 figures, accepted by PAS

Deep Learning for Vanishing Point Detection Using an Inverse Gnomonic Projection

We present a novel approach for vanishing point detection from uncalibrated monocular images. In contrast to state-of-the-art, we make no a priori assumptions about the observed scene. Our method is based on a convolutional neural network (CNN) which does not use natural images, but a Gaussian sphere representation arising from an inverse gnomonic projection of lines detected in an image. This allows us to rely on synthetic data for training, eliminating the need for labelled images. Our method achieves competitive performance on three horizon estimation benchmark datasets. We further highlight some additional use cases for which our vanishing point detection algorithm can be used.Comment: Accepted for publication at German Conference on Pattern Recognition (GCPR) 2017. This research was supported by German Research Foundation DFG within Priority Research Programme 1894 "Volunteered Geographic Information: Interpretation, Visualisation and Social Computing

Southern Ocean GLOBEC moored array and automated weather station data report

Southern Ocean GLOBal ocean ECosystemsAs part of the U.S. Southern Ocean GLOBEC program, moored time series measurements of temperature, conductivity (salinity), pressure, velocity, and acoustic backscatter were made from March 2001 to March 2003 in and near Marguerite Bay, located on the Antarctic Peninsula western shelf. To monitor surface forcing during the moored array observations, two automatic weather stations (AWSs) were deployed on islands in Marguerite Bay and time series of wind, air temperature, pressure, and relative humidity were collected from May 2001 through March 2003. This report describes the individual moorings, their locations and local bathymetry, the instrumentation used and measurement depths, calibration and data processing steps taken to produce final time series, and basic plots of the final time series. The AWS data acquisition and processing are also described and basic plots of the final meteorological time series presented. Directions are given about how to access the raw and processed moored and AWS data via the SO GLOBEC website (http://globec.whoi.edu/jg/dir/globec/soglobec/).Funding was provided by the National Science Foundation under contract number OPP-99-10092

A Spectroscopic Study of Field and Runaway OB Stars

Identifying binaries among runaway O- and B-type stars offers valuable insight into the evolution of open clusters and close binary stars. Here we present a spectroscopic investigation of 12 known or suspected binaries among field and runaway OB stars. We find new orbital solutions for five single-lined spectroscopic binaries (HD 1976, HD 14633, HD 15137, HD 37737, and HD 52533), and we classify two stars thought to be binaries (HD 30614 and HD 188001) as single stars. In addition, we reinvestigate their runaway status using our new radial velocity data with the UCAC2 proper motion catalogs. Seven stars in our study appear to have been ejected from their birthplaces, and at least three of these runaways are spectroscopic binaries and are of great interest for future study.Comment: 21 pages, 1 figure, 7 tables; Accepted to Ap

Theoretical Dependence of the Near-Asymptotic Apparent Optical Properties on the Inherent Optical Properties of Sea Water

The apparent optical properties of sea water are a set of measurables that describe the geometry of the submarine light field. These properties are related to the inherent optical properties—the volume attenuation coefficient and the volume scattering function—through the process of radiative transfer. A numerical approximation to the equation of radiative transfer was programmed for solution on a high-speed digital computer. The technique is based on resolving the hydrosol into a system of thin slabs, finding approximate transmission and reflection operators for each slab, and then systematically applying these operators to determine the geometry of the light field in the interior of the system of slabs. Thus each set of calculations produces the radiance solid as a function of depth. The apparent optical properties were found by numerical integration of the radiance. A simple three-parameter model was used to simplify study of the dependence of the apparent optical properties on the directional characteristics of the volume scattering function.This paper was published in the Journal of the Optical Society of America and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/josa/Issue.cfm. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Keywords: Oceanography, Image formation, Scattering, Luminance, Water, Spread function, Modulation transferKeywords: Oceanography, Image formation, Scattering, Luminance, Water, Spread function, Modulation transfe

The EoR Sensitivity of the Murchison Widefield Array

Using the final 128 antenna locations of the Murchison Widefield Array (MWA), we calculate its sensitivity to the Epoch of Reionization (EoR) power spectrum of red- shifted 21 cm emission for a fiducial model and provide the tools to calculate the sensitivity for any model. Our calculation takes into account synthesis rotation, chro- matic and asymmetrical baseline effects, and excludes modes that will be contaminated by foreground subtraction. For the fiducial model, the MWA will be capable of a 14{\sigma} detection of the EoR signal with one full season of observation on two fields (900 and 700 hours).Comment: 5 pages, 4 figures, 1 table, Accepted for publication in MNRAS Letters. Supplementary material will be available in the published version, or by contacting the author

Effect of lithographically-induced strain relaxation on the magnetic domain configuration in microfabricated epitaxially grown Fe81Ga19

We investigate the role of lithographically-induced strain relaxation in a micron-scaled device fabricated from epitaxial thin films of the magnetostrictive alloy Fe81Ga19. The strain relaxation due to lithographic patterning induces a magnetic anisotropy that competes with the magnetocrystalline and shape induced anisotropy to play a crucial role in stabilising a flux-closing domain pattern. We use magnetic imaging, micromagnetic calculations and linear elastic modelling to investigate a region close to the edges of an etched structure. This highly-strained edge region has a significant influence on the magnetic domain configuration due to an induced magnetic anisotropy resulting from the inverse magnetostriction effect. We investigate the competition between the strain-induced and shape-induced anisotropy energies, and the resultant stable domain configurations, as the width of the bar is reduced to the nanoscale range. Understanding this behaviour will be important when designing hybrid magneto-electric spintronic devices based on highly magnetostrictive materials

Hierarchy and the Provision of Order in International Politics

The anarchic international system is actually heavily structured: communities of states join together for common benefit; strong states form hierarchical relationships with weak states to enforce order and achieve preferred outcomes. Breaking from prior research, we conceptualize structures such as community and hierarchy as properties of networks of states’ interactions that can capture unobserved constraints in state behavior, constraints that may reduce conflict. We offer two claims. One, common membership in trade communities pacifies to the extent that breaking trade ties would entail high switching costs: thus, we expect heavy arms trade, more than most types of commercial trade, to reduce intracommunity conflict. Two, this is driven by hierarchical communities in which strong states can use high switching costs as leverage to constrain conflict between weaker states in the community. We find empirical support for these claims using a time-dependent multilayer network model and a new measure of hierarchy based on network centrality

Mental Health Recovery Narratives and Their Impact on Recipients: Systematic Review and Narrative Synthesis.

OBJECTIVE: Mental health recovery narratives are often shared in peer support work and antistigma campaigns. Internet technology provides access to an almost unlimited number of narratives, and yet little is known about how they affect recipients. The aim of this study was to develop a conceptual framework characterizing the impact of recovery narratives on recipients. METHOD: A systematic review of evidence about the impact of mental health recovery narratives was conducted. Searches used electronic databases ( n = 9), reference tracking, hand-searching of selected journals ( n = 2), grey literature searching, and expert consultation ( n = 7). A conceptual framework was generated through a thematic analysis of included articles, augmented by consultation with a Lived Experience Advisory Panel. RESULTS: In total, 8137 articles were screened. Five articles were included. Forms of impact were connectedness, understanding of recovery, reduction in stigma, validation of personal experience, affective responses, and behavioural responses. Impact was moderated by characteristics of the recipient, context, and narrative. Increases in eating disorder behaviours were identified as a harmful response specific to recipients with eating disorders. CONCLUSIONS: Mental health recovery narratives can promote recovery. Recovery narratives might be useful for clients with limited access to peers and in online interventions targeted at reducing social isolation in rural or remote locations, but support is needed for the processing of the strong emotions that can arise. Caution is needed for use with specific clinical populations. Protocol registration: Prospero-CRD42018090923