Space acceleration measurement system triaxial sensor head error budget

The objective of the Space Acceleration Measurement System (SAMS) is to measure and record the microgravity environment for a given experiment aboard the Space Shuttle. To accomplish this, SAMS uses remote triaxial sensor heads (TSH) that can be mounted directly on or near an experiment. The errors of the TSH are reduced by calibrating it before and after each flight. The associated error budget for the calibration procedure is discussed here

Fresnel filtering in lasing emission from scarred modes of wave-chaotic optical resonators

We study lasing emission from asymmetric resonant cavity (ARC) GaN micro-lasers. By comparing far-field intensity patterns with images of the micro-laser we find that the lasing modes are concentrated on three-bounce unstable periodic ray orbits, i.e. the modes are scarred. The high-intensity emission directions of these scarred modes are completely different from those predicted by applying Snell's law to the ray orbit. This effect is due to the process of ``Fresnel filtering'' which occurs when a beam of finite angular spread is incident at the critical angle for total internal reflection.Comment: 4 pages, 3 figures (eps), RevTeX 3.1, submitted to Phys. Rev. Lett; corrected a minor (transcription) erro

Correspondence between structure and function in the human brain at rest

To further understanding of basic and complex cognitive functions, previous connectome research has identified functional and structural connections of the human brain. Functional connectivity is often measured by using resting-state functional magnetic resonance imaging (rs-fMRI) and is generally interpreted as an indirect measure of neuronal activity. Gray matter (GM) primarily consists of neuronal and glia cell bodies; therefore, it is surprising that the majority of connectome research has excluded GM measures. Therefore, we propose that by exploring where GM corresponds to function would aid in the understanding of both structural and functional connectivity and in turn the human connectome. A cohort of 603 healthy participants underwent structural and functional scanning on the same 3 T scanner at the Mind Research Network. To investigate the spatial correspondence between structure and function, spatial independent component analysis (ICA) was applied separately to both GM density (GMD) maps and to rs-fMRI data. ICA of GM delineates structural components based on the covariation of GMD regions among subjects. For the rs-fMRI data, ICA identified spatial patterns with common temporal features. These decomposed structural and functional components were then compared by spatial correlation. Basal ganglia components exhibited the highest structural to resting-state functional spatial correlation (r = 0.59). Cortical components generally show correspondence between a single structural component and several resting-state functional components. We also studied relationships between the weights of different structural components and identified the precuneus as a hub in GMD structural network correlations. In addition, we analyzed relationships between component weights, age, and gender; concluding that age has a significant effect on structural components

Coupled KdV equations derived from atmospherical dynamics

Some types of coupled Korteweg de-Vries (KdV) equations are derived from an atmospheric dynamical system. In the derivation procedure, an unreasonable $y$-average trick (which is usually adopted in literature) is removed. The derived models are classified via Painlev\'e test. Three types of $\tau$-function solutions and multiple soliton solutions of the models are explicitly given by means of the exact solutions of the usual KdV equation. It is also interesting that for a non-Painlev\'e integrable coupled KdV system there may be multiple soliton solutions.Comment: 19 pages, 2 figure

Current Status and New Challenges of The Tunka Radio Extension

The Tunka Radio Extension (Tunka-Rex) is an antenna array spread over an area of about 1~km$^2$. The array is placed at the Tunka Advanced Instrument for cosmic rays and Gamma Astronomy (TAIGA) and detects the radio emission of air showers in the band of 30 to 80~MHz. During the last years it was shown that a sparse array such as Tunka-Rex is capable of reconstructing the parameters of the primary particle as accurate as the modern instruments. Based on these results we continue developing our data analysis. Our next goal is the reconstruction of cosmic-ray energy spectrum observed only by a radio instrument. Taking a step towards it, we develop a model of aperture of our instrument and test it against hybrid TAIGA observations and Monte-Carlo simulations. In the present work we give an overview of the current status and results for the last five years of operation of Tunka-Rex and discuss prospects of the cosmic-ray energy estimation with sparse radio arrays.Comment: Proceedings of E+CRS 201

Reduced Left Executive Control Network Functional Connectivity Is Associated with Alcohol Use Disorders

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108693/1/acer12505.pd

First analysis of inclined air showers detected by Tunka-Rex

The Tunka Radio Extension (Tunka-Rex) is a digital antenna array for the detection of radio emission from cosmic-ray air showers in the frequency band of 30 to 80 MHz and for primary energies above 100 PeV. The standard analysis of Tunka-Rex includes events with zenith angle of up to 50$^\circ$. This cut is determined by the efficiency of the external trigger. However, due to the air-shower footprint increasing with zenith angle and due to the more efficient generation of radio emission (the magnetic field in the Tunka valley is almost vertical), there are a number of ultra-high-energy inclined events detected by Tunka-Rex. In this work we present a first analysis of a subset of inclined events detected by Tunka-Rex. We estimate the energies of the selected events and test the efficiency of Tunka-Rex antennas for detection of inclined air showers.Comment: ARENA2018 proceeding

In Situ High-Temperature Raman Spectroscopy Via a Remote Fiber-Optic Raman Probe

This Study Demonstrated for the First Time an in Situ High-Temperature Fiber-Optic Raman Probe to Study the Structure of Glass and Slag Samples at Temperatures Up to 1400 °C. a Customized External Telescope Was Integrated into a Portable Fiber-Optic Raman Probe to Extend the Optical Working Distance to Allow the Probe to Work in a High-Temperature Environment. Three Samples Were Evaluated to Demonstrate the Functionality of the High-Temperature Fiber-Optic Raman Probe. Room Temperature and High-Temperature Raman Spectra Were Successfully Collected and Analyzed. in Addition, a Deconvolution Algorithm Was Used to Identify Peaks in the Spectrum that Could Then Be Related to the Molecular Structure of Components in Each Sample. This Flexible and Reliable High-Temperature Raman Measurement Method Has Great Potential for Various Applications, Such as Materials Development, Composition, and Structure Monitoring during High-Temperature Processing, Chemical Identification, and Process Monitoring in Industrial Production

SANEPIC: A Map-Making Method for Timestream Data From Large Arrays

We describe a map-making method which we have developed for the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) experiment, but which should have general application to data from other submillimeter arrays. Our method uses a Maximum Likelihood based approach, with several approximations, which allows images to be constructed using large amounts of data with fairly modest computer memory and processing requirements. This new approach, Signal And Noise Estimation Procedure Including Correlations (SANEPIC), builds upon several previous methods, but focuses specifically on the regime where there is a large number of detectors sampling the same map of the sky, and explicitly allowing for the the possibility of strong correlations between the detector timestreams. We provide real and simulated examples of how well this method performs compared with more simplistic map-makers based on filtering. We discuss two separate implementations of SANEPIC: a brute-force approach, in which the inverse pixel-pixel covariance matrix is computed; and an iterative approach, which is much more efficient for large maps. SANEPIC has been successfully used to produce maps using data from the 2005 BLAST flight.Comment: 27 Pages, 15 figures; Submitted to the Astrophysical Journal; related results available at http://blastexperiment.info/ [the BLAST Webpage

In Situ and Real-Time Mold Flux Analysis using a High-Temperature Fiber-Optic Raman Sensor for Steel Manufacturing Applications

Continuous Casting in Steel Production Uses Specially Developed Oxyfluoride Glasses (Mold Fluxes) to Lubricate a Mold and Control the Solidification of the Steel in the Mold. the Composition of the Flux Impacts Properties, Including Basicity, Viscosity, and Crystallization Rate, All of Which Affect the Stability of the Casting Process and the Quality of the Solidified Steel. However, Mold Fluxes Interact with Steel during the Casting Process, Resulting in Flux Chemistry Changes that Must Be Considered in the Flux Design. Currently, the Chemical Composition of Mold Flux Must Be Determined by Extracting Flux Samples from the Mold during Casting and Then Processing These Samples Offline to Estimate the Working Chemical Composition And, Therefore, the Expected Properties of the Flux. Raman Spectroscopy Offers an Alternative Method for Performing Flux Analysis with the Potential to Perform Measurements Online during the Casting Process. Raman Spectroscopy Uniquely Identifies Specific Chemical Bonds and Symmetries in the Glassy Flux by Revealing Peaks that Are a Fingerprint of the Vibration Modes of Molecules in the Flux. the Intensities of Specific Peaks in Raman Spectra Can Be Correlated with the Chemical Composition of the Melt and Associated Properties Such as Basicity and Viscosity. This Paper Reports on the First Use of a Portable Fiber-Optic Raman Sensor for in Situ Raman Spectroscopic Measurements of Molten Flux at 1400°C. the Work Demonstrates the Advantages of Fiber-Optic Raman Spectroscopy to Document the Structure and Chemical Composition of Flux Samples at Temperatures Typically Encountered in the Mold during Continuous Caster Operation. Experimental Results Demonstrate that the Composition-Dependent Raman Signal Shifts Can Be Detected at Caster Operating Temperatures, and the Use of High-Temperature Raman Analysis for In-Line Flux Monitoring Shows Significant Promise for the in Situ Detection of Changes in Flux Composition and Physical Properties during Casting