763 research outputs found
Unsupervised RGB-to-Thermal Domain Adaptation via Multi-Domain Attention Network
This work presents a new method for unsupervised thermal image classification
and semantic segmentation by transferring knowledge from the RGB domain using a
multi-domain attention network. Our method does not require any thermal
annotations or co-registered RGB-thermal pairs, enabling robots to perform
visual tasks at night and in adverse weather conditions without incurring
additional costs of data labeling and registration. Current unsupervised domain
adaptation methods look to align global images or features across domains.
However, when the domain shift is significantly larger for cross-modal data,
not all features can be transferred. We solve this problem by using a shared
backbone network that promotes generalization, and domain-specific attention
that reduces negative transfer by attending to domain-invariant and
easily-transferable features. Our approach outperforms the state-of-the-art
RGB-to-thermal adaptation method in classification benchmarks, and is
successfully applied to thermal river scene segmentation using only synthetic
RGB images. Our code is made publicly available at
https://github.com/ganlumomo/thermal-uda-attention
Towards a Work Breakdown Structure for Net Centric System of Systems Engineering and Management
As the system engineering industry sees an increasing focus on the lifecycle development, acquisition, and sustainment of net-centric Systems of Systems (SoS), organizations find that current processes and tools need to evolve to handle the increased scope, scale, and complexity of these efforts. One such tool, the Work Breakdown Structure (WBS) is important in planning, monitoring, and re-focusing of program activities as requirements and goals of the program evolve. This paper provides an overview of the limitations of current standard WBSs with respect to SoS efforts and presents a proposed WBS structure that more adequately reflects the evolving processes and cross-organizational complexities
Online Self-Supervised Thermal Water Segmentation for Aerial Vehicles
We present a new method to adapt an RGB-trained water segmentation network to
target-domain aerial thermal imagery using online self-supervision by
leveraging texture and motion cues as supervisory signals. This new thermal
capability enables current autonomous aerial robots operating in near-shore
environments to perform tasks such as visual navigation, bathymetry, and flow
tracking at night. Our method overcomes the problem of scarce and
difficult-to-obtain near-shore thermal data that prevents the application of
conventional supervised and unsupervised methods. In this work, we curate the
first aerial thermal near-shore dataset, show that our approach outperforms
fully-supervised segmentation models trained on limited target-domain thermal
data, and demonstrate real-time capabilities onboard an Nvidia Jetson embedded
computing platform. Code and datasets used in this work will be available at:
https://github.com/connorlee77/uav-thermal-water-segmentation.Comment: 8 pages, 4 figures, 3 table
RGB-X Object Detection via Scene-Specific Fusion Modules
Multimodal deep sensor fusion has the potential to enable autonomous vehicles
to visually understand their surrounding environments in all weather
conditions. However, existing deep sensor fusion methods usually employ
convoluted architectures with intermingled multimodal features, requiring large
coregistered multimodal datasets for training. In this work, we present an
efficient and modular RGB-X fusion network that can leverage and fuse
pretrained single-modal models via scene-specific fusion modules, thereby
enabling joint input-adaptive network architectures to be created using small,
coregistered multimodal datasets. Our experiments demonstrate the superiority
of our method compared to existing works on RGB-thermal and RGB-gated datasets,
performing fusion using only a small amount of additional parameters. Our code
is available at https://github.com/dsriaditya999/RGBXFusion.Comment: Accepted to 2024 IEEE/CVF Winter Conference on Applications of
Computer Vision (WACV 2024
A preliminary study: Does relationship closeness with grandchildren correlate with the quality of life and physical health of Malaysian Chinese elderly?
The 13th Next-Generation Global Workshop第13回次世代グローバルワークショップテーマ: New Risks and Resilience in Asian Societies and the World 日程: 21-23 November, 2020 開催場所: ベトナム社会科学院(ハノイ)/Vietnam Academy of Social Sciences(No. 1 Lieu Giai street, Ba Dinh, Hanoi, Vietnam) ※Due to the COVID-19, the workshop will be held at ONLINE for overseas participants(not from Vietnam)/ONSITE for Vietnamese participants.This preliminary mixed-method study aimed to investigate whether grandparental childcare can contribute to elderly' quality of life and physical health. In the quantitative study, a total of 97 Chinese grandparents who are primary caregivers were recruited to examine the relations of relationship closeness, quality of life and physical health. Correlational analysis revealed that grandparent-grandchildren relationship closeness positively correlated with self-rated quality of life and physical health of the grandparents. In the qualitative interview, grandmothers (n = four Chinese grandmothers) who are primary caregivers were recruited to share their experience in taking care of grandchildren. Findings from the thematic analysis revealed that all grandmothers have a close relationship with their grandchildren. In specific, they are happy with the companionship of grandchildren even though they may feel physically tired in taking care of grandchildren. This preliminary study on skipped generation family provides insights into understanding the contribution of relationship closeness with grandchildren on the perceived quality of life and physical health of Malaysian grandparents who are the primary caregiver to their grandchildren
Spatiotemporal correlations of handset-based service usages
We study spatiotemporal correlations and temporal diversities of
handset-based service usages by analyzing a dataset that includes detailed
information about locations and service usages of 124 users over 16 months. By
constructing the spatiotemporal trajectories of the users we detect several
meaningful places or contexts for each one of them and show how the context
affects the service usage patterns. We find that temporal patterns of service
usages are bound to the typical weekly cycles of humans, yet they show maximal
activities at different times. We first discuss their temporal correlations and
then investigate the time-ordering behavior of communication services like
calls being followed by the non-communication services like applications. We
also find that the behavioral overlap network based on the clustering of
temporal patterns is comparable to the communication network of users. Our
approach provides a useful framework for handset-based data analysis and helps
us to understand the complexities of information and communications technology
enabled human behavior.Comment: 11 pages, 15 figure
Quasars Probing Quasars. VI. Excess H I Absorption within one Proper Mpc of z ~ 2 Quasars
With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar's environment in absorption. We use a sample of 650 projected quasar pairs to study the H I Lyα absorption transverse to luminous, z ~ 2 quasars at proper separations of 30 kpc 10^(17.3) cm^(-2) at separations R_⊥ < 200 kpc, which decreases to ~20% at R_⊥ ≃ 1 Mpc, but still represents a significant excess over the cosmic average. This excess of optically thick absorption can be described by a quasar-absorber cross-correlation function ξ_(QA)(r) = (r/r_0)^γ with a large correlation length r_0=12.5^(+2.7)_(-1.4)h^(-1)Mpc(comoving) and y =1.68^(+0.14)_(-0.30). The H I absorption measured around quasars exceeds that of any previously studied population, consistent with quasars being hosted by massive dark matter halos M_(halo) ≈ 10^(12.5) M_☉ at z ~ 2.5. The environments of these massive halos are highly biased toward producing optically thick gas, and may even dominate the cosmic abundance of Lyman limit systems and hence the intergalactic opacity to ionizing photons at z ~ 2.5. The anisotropic absorption around quasars implies the transverse direction is much less likely to be illuminated by ionizing radiation than the line-of-sight
Baryon Acoustic Oscillations in the Ly{\alpha} forest of BOSS DR11 quasars
We report a detection of the baryon acoustic oscillation (BAO) feature in the
flux-correlation function of the Ly{\alpha} forest of high-redshift quasars
with a statistical significance of five standard deviations. The study uses
137,562 quasars in the redshift range from the Data Release
11 (DR11) of the Baryon Oscillation Spectroscopic Survey (BOSS) of SDSS-III.
This sample contains three times the number of quasars used in previous
studies. The measured position of the BAO peak determines the angular distance,
and expansion rate, , both on a scale set by the sound
horizon at the drag epoch, . We find
and
where . The optimal
combination, is determined with a precision of
. For the value , consistent with the CMB power
spectrum measured by Planck, we find
and . Tests with mock
catalogs and variations of our analysis procedure have revealed no systematic
uncertainties comparable to our statistical errors. Our results agree with the
previously reported BAO measurement at the same redshift using the
quasar-Ly{\alpha} forest cross-correlation. The auto-correlation and
cross-correlation approaches are complementary because of the quite different
impact of redshift-space distortion on the two measurements. The combined
constraints from the two correlation functions imply values of and
that are, respectively, 7% low and 7% high compared to the
predictions of a flat CDM cosmological model with the best-fit Planck
parameters. With our estimated statistical errors, the significance of this
discrepancy is .Comment: Accepted for publication in A&A. 17 pages, 18 figure
The SDSS-III Baryon Oscillation Spectroscopic Survey: Quasar Target Selection for Data Release Nine
The SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), a five-year
spectroscopic survey of 10,000 deg^2, achieved first light in late 2009. One of
the key goals of BOSS is to measure the signature of baryon acoustic
oscillations in the distribution of Ly-alpha absorption from the spectra of a
sample of ~150,000 z>2.2 quasars. Along with measuring the angular diameter
distance at z\approx2.5, BOSS will provide the first direct measurement of the
expansion rate of the Universe at z > 2. One of the biggest challenges in
achieving this goal is an efficient target selection algorithm for quasars over
2.2 < z < 3.5, where their colors overlap those of stars. During the first year
of the BOSS survey, quasar target selection methods were developed and tested
to meet the requirement of delivering at least 15 quasars deg^-2 in this
redshift range, out of 40 targets deg^-2. To achieve these surface densities,
the magnitude limit of the quasar targets was set at g <= 22.0 or r<=21.85.
While detection of the BAO signature in the Ly-alpha absorption in quasar
spectra does not require a uniform target selection, many other astrophysical
studies do. We therefore defined a uniformly-selected subsample of 20 targets
deg^-2, for which the selection efficiency is just over 50%. This "CORE"
subsample will be fixed for Years Two through Five of the survey. In this paper
we describe the evolution and implementation of the BOSS quasar target
selection algorithms during the first two years of BOSS operations. We analyze
the spectra obtained during the first year. 11,263 new z>2.2 quasars were
spectroscopically confirmed by BOSS. Our current algorithms select an average
of 15 z > 2.2 quasars deg^-2 from 40 targets deg^-2 using single-epoch SDSS
imaging. Multi-epoch optical data and data at other wavelengths can further
improve the efficiency and completeness of BOSS quasar target selection.
[Abridged]Comment: 33 pages, 26 figures, 12 tables and a whole bunch of quasars.
Submitted to Ap
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