3,651 research outputs found
Pseudo Mask Augmented Object Detection
In this work, we present a novel and effective framework to facilitate object
detection with the instance-level segmentation information that is only
supervised by bounding box annotation. Starting from the joint object detection
and instance segmentation network, we propose to recursively estimate the
pseudo ground-truth object masks from the instance-level object segmentation
network training, and then enhance the detection network with top-down
segmentation feedbacks. The pseudo ground truth mask and network parameters are
optimized alternatively to mutually benefit each other. To obtain the promising
pseudo masks in each iteration, we embed a graphical inference that
incorporates the low-level image appearance consistency and the bounding box
annotations to refine the segmentation masks predicted by the segmentation
network. Our approach progressively improves the object detection performance
by incorporating the detailed pixel-wise information learned from the
weakly-supervised segmentation network. Extensive evaluation on the detection
task in PASCAL VOC 2007 and 2012 [12] verifies that the proposed approach is
effective
Ranking Medical Subject Headings using a factor graph model.
Automatically assigning MeSH (Medical Subject Headings) to articles is an active research topic. Recent work demonstrated the feasibility of improving the existing automated Medical Text Indexer (MTI) system, developed at the National Library of Medicine (NLM). Encouraged by this work, we propose a novel data-driven approach that uses semantic distances in the MeSH ontology for automated MeSH assignment. Specifically, we developed a graphical model to propagate belief through a citation network to provide robust MeSH main heading (MH) recommendation. Our preliminary results indicate that this approach can reach high Mean Average Precision (MAP) in some scenarios
Fractal analysis of the effect of particle aggregation distribution on thermal conductivity of nanofluids
This project was supported by the National Natural Science Foundation of China (No. 41572116), the Fundamental Research Funds for the Central Universities, China University of Geosciences, Wuhan) (No. CUG160602).Peer reviewedPostprin
Phase Lag and Coherence Function of X-ray emission from Black Hole Candidate XTE J1550-564
We report the results from measuring the phase lag and coherence function of
X-ray emission from black hole candidate (BHC) XTE J1550-564. These X-ray
temporal properties have been recognized to be increasingly important in
providing important diagnostics of the dynamics of accretion flows around black
holes. For XTE J1550-564, we found significant hard lag --- the X-ray
variability in high energy bands {\em lags} behind that in low energy bands ---
associated both with broad-band variability and quasi-periodic oscillation
(QPO). However, the situation is more complicated for the QPO: while hard lag
was measured for the first harmonic of the signal, the fundamental component
showed significant {\em soft} lag. Such behavior is remarkably similar to what
was observed of microquasar GRS 1915+105. The phase lag evolved during the
initial rising phase of the 1998 outburst. The magnitude of both the soft and
hard lags of the QPO increases with X-ray flux, while the Fourier spectrum of
the broad-band lag varies significantly in shape. The coherence function is
relatively high and roughly constant at low frequencies, and begins to drop
almost right after the first harmonic of the QPO. It is near unity at the
beginning and decreases rapidly during the rising phase. Also observed is that
the more widely separated the two energy bands are the less the coherence
function between the two. It is interesting that the coherence function
increases significantly at the frequencies of the QPO and its harmonics. We
discuss the implications of the results on the models proposed for BHCs.Comment: To appear in ApJ Letter
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