1,122 research outputs found
Depression detection from short utterances via diverse smartphones in natural environmental conditions
Depression is a leading cause of disease burden worldwide, however there is an unmet need for screening and diagnostic measures that can be widely deployed in real-world environments. Voice-based diagnostic methods are convenient, non-invasive to elicit, and can be collected and processed in near real-time using modern smartphones, smart speakers, and other devices. Studies in voice-based depression detection to date have primarily focused on laboratory-collected voice samples, which are not representative of typical user environments or devices. This paper conducts the first investigation of voice-based depression assessment techniques on real-world data from 887 speakers, recorded using a variety of different smartphones. Evaluations on 16 hours of speech show that conservative segment selection strategies using highly thresholded voice activity detection, coupled with tailored normalization approaches are effective for mitigating smartphone channel variability and background environmental noise. Together, these strategies can achieve F1 scores comparable with or better than those from a combination of clean recordings, a single recording environment and long utterances. The scalability of speech elicitation via smartphone allows detailed models dependent on gender, smartphone manufacturer and/or elicitation task. Interestingly, results herein suggest that normalization based on these criteria may be more effective than tailored models for detecting depressed speech
Emergence of time-horizon invariant correlation structure in financial returns by subtraction of the market mode
We investigate the emergence of a structure in the correlation matrix of
assets' returns as the time-horizon over which returns are computed increases
from the minutes to the daily scale. We analyze data from different stock
markets (New York, Paris, London, Milano) and with different methods. Result
crucially depends on whether the data is restricted to the ``internal''
dynamics of the market, where the ``center of mass'' motion (the market mode)
is removed or not. If the market mode is not removed, we find that the
structure emerges, as the time-horizon increases, from splitting a single large
cluster. In NYSE we find that when the market mode is removed, the structure of
correlation at the daily scale is already well defined at the 5 minutes
time-horizon, and this structure accounts for 80 % of the classification of
stocks in economic sectors. Similar results, though less sharp, are found for
the other markets. We also find that the structure of correlations in the
overnight returns is markedly different from that of intraday activity.Comment: 12 pages, 17 figure
The SIDE dual VIS-NIR fiber fed spectrograph for the 10.4 m Gran Telescopio Canarias
SIDE (Super Ifu Deployable Experiment) is proposed as second-generation,
common-user instrument for the GTC. It will be a low and intermediate
resolution fiber fed spectrograph, highly efficient in multi-object and 3D
spectroscopy. The low resolution part (R = 1500, 4000) is called Dual VIS-NIR
because it will observe in the VIS and NIR bands (0.4 ~V 1.7 microns)
simultaneously. Because of the large number of fibers, a set of ~10 identical
spectrographs is needed, each with a mirror collimator, a dichroic and two
refractive cameras. The cameras are optimized for 0.4 - 0.95 microns (VIS) and
0.95 - 1.7 microns (NIR) respectively.Comment: To appear in "Advanced Optical and Mechanical Technologies in
Telescopes and Instrumentation" SPIE conference Proc. 7018, Marseille, 23-28
June 200
NICMOS Imaging of the Nuclei of Arp 220
We report high resolution imaging of the ultraluminous infrared galaxy Arp
220 at 1.1, 1.6, and 2.22 microns with NICMOS on the HST. The
diffraction-limited images at 0.1--0.2 arcsecond resolution clearly resolve
both nuclei of the merging galaxy system and reveal for the first time a number
of luminous star clusters in the circumnuclear envelope. The morphologies of
both nuclei are strongly affected by dust obscuration, even at 2.2 microns :
the primary nucleus (west) presents a crescent shape, concave to the south and
the secondary (eastern) nucleus is bifurcated by a dust lane with the southern
component being very reddened. In the western nucleus, the morphology of the
2.2 micron emission is most likely the result of obscuration by an opaque disk
embedded within the nuclear star cluster. The morphology of the central
starburst-cluster in the western nucleus is consistent with either a
circumnuclear ring of star formation or a spherical cluster with the bottom
half obscured by the embedded dust disk. Comparison of cm-wave radio continuum
maps with the near-infrared images suggests that the radio nuclei lie in the
dust disk on the west and near the highly reddened southern component of the
eastern complex. The radio nuclei are separated by 0.98 arcseconds
(corresponding to 364 pc at 77 Mpc) and the half-widths of the infrared nuclei
are approximately 0.2-0.5 arcseconds. At least 8, unresolved infrared sources
-- probably globular clusters -- are also seen in the circumnuclear envelope at
radii 2-7 arcseconds . Their near-infrared colors do not significantly
constrain their ages.Comment: LaTex, 15 pages with 1 gif figure and 5 postscript figures. ApJL
accepte
Using Water Chemistry Data to Assess Stormwater Pathways in Lowland Watersheds
2012 S.C. Water Resources Conference - Exploring Opportunities for Collaborative Water Research, Policy and Managemen
The Role of Landscape Connectivity in Planning and Implementing Conservation and Restoration Priorities. Issues in Ecology
Landscape connectivity, the extent to which a landscape facilitates the movements of organisms and their genes, faces critical threats from both fragmentation and habitat loss. Many conservation efforts focus on protecting and enhancing connectivity to offset the impacts of habitat loss and fragmentation on biodiversity conservation, and to increase the resilience of reserve networks to potential threats associated with climate change. Loss of connectivity can reduce the size and quality of available habitat, impede and disrupt movement (including dispersal) to new habitats, and affect seasonal migration patterns. These changes can lead, in turn, to detrimental effects for populations and species, including decreased carrying capacity, population declines, loss of genetic variation, and ultimately species extinction. Measuring and mapping connectivity is facilitated by a growing number of quantitative approaches that can integrate large amounts of information about organisms’ life histories, habitat quality, and other features essential to evaluating connectivity for a given population or species. However, identifying effective approaches for maintaining and restoring connectivity poses several challenges, and our understanding of how connectivity should be designed to mitigate the impacts of climate change is, as yet, in its infancy. Scientists and managers must confront and overcome several challenges inherent in evaluating and planning for connectivity, including: •characterizing the biology of focal species; •understanding the strengths and the limitations of the models used to evaluate connectivity; •considering spatial and temporal extent in connectivity planning; •using caution in extrapolating results outside of observed conditions; •considering non-linear relationships that can complicate assumed or expected ecological responses; •accounting and planning for anthropogenic change in the landscape; •using well-defined goals and objectives to drive the selection of methods used for evaluating and planning for connectivity; •and communicating to the general public in clear and meaningful language the importance of connectivity to improve awareness and strengthen policies for ensuring conservation. Several aspects of connectivity science deserve additional attention in order to improve the effectiveness of design and implementation. Research on species persistence, behavioral ecology, and community structure is needed to reduce the uncertainty associated with connectivity models. Evaluating and testing connectivity responses to climate change will be critical to achieving conservation goals in the face of the rapid changes that will confront many communities and ecosystems. All of these potential areas of advancement will fall short of conservation goals if we do not effectively incorporate human activities into connectivity planning. While this Issue identifies substantial uncertainties in mapping connectivity and evaluating resilience to climate change, it is also clear that integrating human and natural landscape conservation planning to enhance habitat connectivity is essential for biodiversity conservation
Investigating word affect features and fusion of probabilistic predictions incorporating uncertainty in AVEC 2017
© 2017 Association for Computing Machinery. Predicting emotion intensity and severity of depression are both challenging and important problems within the broader field of affective computing. As part of the AVEC 2017, we developed a number of systems to accomplish these tasks. In particular, word affect features, which derive human affect ratings (e.g. arousal and valence) from transcripts, were investigated for predicting depression severity and liking, showing great promise. A simple system based on the word affect features achieved an RMSE of 6.02 on the test set, yielding a relative improvement of 13.6% over the baseline. For the emotion prediction sub-challenge, we investigated multimodal fusion, which incorporated a measure of uncertainty associated with each prediction within an Output-Associative fusion framework for arousal and valence prediction, whilst liking prediction systems mainly focused on text-based features. Our best emotion prediction systems provided significant relative improvements over the baseline on the test set of 39.5%, 17.6%, and 29.3% for arousal, valence, and liking. Of particular note is that consistent improvements were observed when incorporating prediction uncertainty across various system configurations for predicting arousal and valence, suggesting the importance of taking into consideration prediction uncertainty for fusion and more broadly the advantages of probabilistic predictions
The Keck Low-Resolution Imaging Spectrometer
The Low Resolution Imaging Spectrometer (LRIS) for the Cassegrain focus of the Keck 10-m telescope on Mauna Kea is described. It has an imaging mode so it can also be used for taking direct images. The field of view in both spectrographic and imaging modes is 6 by 7.8 arcmin. It can be used with both conventional slits and custom-punched slit masks. The optical quality of the spectrograph is good enough to take full advantage of the excellent imaging properties of the telescope itself. The detector is a cooled back-illuminated Tektronics Inc. 2048 X 2048 CCD which gives a sampling rate of 4.685 pixels per arcsec. In the spectrographic mode the spectrograph has a maximum efficiency at the peak of the grating blaze of 32%-34% for the two lowest resolution gratings and 28% for the 1200 g mm^(-1) grating. This efficiency includes the detector but not the telescope or the atmosphere
ESI, a new Keck Observatory echellette spectrograph and imager
The Echellette Spectrograph and Imager (ESI) is a multipurpose instrument
which has been delivered by the Instrument Development Laboratory of Lick
Observatory for use at the Cassegrain focus of the Keck II telescope. ESI saw
first light on August 29, 1999. ESI is a multi-mode instrument that enables the
observer to seamlessly switch between three modes during an observation. The
three modes of ESI are: An R=13,000-echellette mode; Low-dispersion prismatic
mode; Direct imaging mode. ESI contains a unique flexure compensation system
which reduces the small instrument flexure to negligible proportions.
Long-exposure images on the sky show FWHM spot diameters of 34 microns (0.34")
averaged over the entire field of view. These are the best non-AO images taken
in the visible at Keck Observatory to date. Maximum efficiencies are measured
to be 28% for the echellette mode and greater than 41% for low-dispersion
prismatic mode including atmospheric, telescope and detector losses. In this
paper we describe the instrument and its development. We also discuss the
performance-testing and some observational results.Comment: 10 pages, 14 figures, 8tables, accepted for publication in PASP, 15
April 200
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