7,861 research outputs found
4-Bromo-3-hydroxy-3-(4-hydroxy-2-oxo-2H-chromen-3-yl)indolin-2-one
In the molecule of the title compound, C17H10BrNO5, the indoline system and the attached coumarin ring are each essentially planar with maximum deviations of 0.074 (2) and 0.062 (2) Å, respectively. The dihedral angle between them is 85.09 (3)°. In the crystal, all heteroatoms (except for the coumarin oxo O atoms) are involved in intra- and intermolecular hydrogen bonds. An intramolecular O—H⋯O hydrogen bond occurs. In the crystal, molecules are linked through O—H⋯O, N—H⋯O and C—H⋯O contacts, forming a complex three-dimensional structure
A Causal And-Or Graph Model for Visibility Fluent Reasoning in Tracking Interacting Objects
Tracking humans that are interacting with the other subjects or environment
remains unsolved in visual tracking, because the visibility of the human of
interests in videos is unknown and might vary over time. In particular, it is
still difficult for state-of-the-art human trackers to recover complete human
trajectories in crowded scenes with frequent human interactions. In this work,
we consider the visibility status of a subject as a fluent variable, whose
change is mostly attributed to the subject's interaction with the surrounding,
e.g., crossing behind another object, entering a building, or getting into a
vehicle, etc. We introduce a Causal And-Or Graph (C-AOG) to represent the
causal-effect relations between an object's visibility fluent and its
activities, and develop a probabilistic graph model to jointly reason the
visibility fluent change (e.g., from visible to invisible) and track humans in
videos. We formulate this joint task as an iterative search of a feasible
causal graph structure that enables fast search algorithm, e.g., dynamic
programming method. We apply the proposed method on challenging video sequences
to evaluate its capabilities of estimating visibility fluent changes of
subjects and tracking subjects of interests over time. Results with comparisons
demonstrate that our method outperforms the alternative trackers and can
recover complete trajectories of humans in complicated scenarios with frequent
human interactions.Comment: accepted by CVPR 201
Discrete Multi-modal Hashing with Canonical Views for Robust Mobile Landmark Search
Mobile landmark search (MLS) recently receives increasing attention for its
great practical values. However, it still remains unsolved due to two important
challenges. One is high bandwidth consumption of query transmission, and the
other is the huge visual variations of query images sent from mobile devices.
In this paper, we propose a novel hashing scheme, named as canonical view based
discrete multi-modal hashing (CV-DMH), to handle these problems via a novel
three-stage learning procedure. First, a submodular function is designed to
measure visual representativeness and redundancy of a view set. With it,
canonical views, which capture key visual appearances of landmark with limited
redundancy, are efficiently discovered with an iterative mining strategy.
Second, multi-modal sparse coding is applied to transform visual features from
multiple modalities into an intermediate representation. It can robustly and
adaptively characterize visual contents of varied landmark images with certain
canonical views. Finally, compact binary codes are learned on intermediate
representation within a tailored discrete binary embedding model which
preserves visual relations of images measured with canonical views and removes
the involved noises. In this part, we develop a new augmented Lagrangian
multiplier (ALM) based optimization method to directly solve the discrete
binary codes. We can not only explicitly deal with the discrete constraint, but
also consider the bit-uncorrelated constraint and balance constraint together.
Experiments on real world landmark datasets demonstrate the superior
performance of CV-DMH over several state-of-the-art methods
On Covering Simplices by Dilations in Dimensions 3 and 4
We propose a conjecture regarding the integrally closedness of lattice
polytopes with large lattice lengths. We demonstrate that a lattice simplex in
dimension 3 (resp. 4) with lattice length of at least 2 (resp. 3 and no edge
has lattice length 5) can be covered by dilated simplices of the form ,
where integer (resp. 3) and is a lattice simplex. The covering
property implies these simplices are integrally closed. As an application, we
derive a simple criterion for the projective normality of ample line bundles on
weighted projective spaces of dimension 3 (resp. 4). Along the way, we discover
certain unexpected phenomenon.Comment: Comments are welcom
Processes of intraseasonal snow cover variations over the eastern China during boreal winter
This study reveals that the dominant time scale of intraseasonal snow cover variation over the eastern China is within 30 days by using the latest satellite snow cover data from the moderate resolution imaging spectroradiometer (MODIS)/Terra product. The leading empirical orthogonal function (EOF) mode of 10–30‐day snow cover variation during boreal winter from 2004 to 2018 over the eastern China has two centers: northwest part of the eastern China and north of the Yangtze River. Composite analysis based on 25 snow events identified from normalized leading principal time series (PC1) indicates that the southeastward intrusion of surface anticyclonic anomalies and accompanying low temperature anomalies provide the temperature condition for snow events. Negative Arctic Oscillation induces mid‐latitude wave train and leads to the development of surface anticyclonic anomalies and upper‐level cyclonic anomalies over East Asia. The cyclonic anomalies induce ascending motion and anomalous convergence of water vapor fluxes over the eastern China, which supplies moisture for snowfall.(a) Time evolution of composite NAO index (pink curve), AO index (blue curve), regional mean surface air temperature anomalies (°C) (black curve) and snow cover anomalies (%) (red curve) in the region of 20–40°N, 105–120°E. (b) Time evolution of composite anomalies of regional mean snow cover tendency (%/day) (black curve), vertical velocity (Pa/s) (blue curve), and divergence of water vapor flux integral from 1,000 to 100‐hPa (*10−6 kg/(m2*s)) (pink curve) in the region of 20–40°N, 105–120°E. Dots on the curves indicate anomalies significant at the 95% confidence level.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149343/1/asl2901_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149343/2/asl2901.pd
Reverse spatial visual top-k query
With the wide application of mobile Internet techniques an location-based services (LBS), massive multimedia data with geo-tags has been generated and collected. In this paper, we investigate a novel type of spatial query problem, named reverse spatial visual top- query (RSVQ k ) that aims to retrieve a set of geo-images that have the query as one of the most relevant geo-images in both geographical proximity and visual similarity. Existing approaches for reverse top- queries are not suitable to address this problem because they cannot effectively process unstructured data, such as image. To this end, firstly we propose the definition of RSVQ k problem and introduce the similarity measurement. A novel hybrid index, named VR 2 -Tree is designed, which is a combination of visual representation of geo-image and R-Tree. Besides, an extension of VR 2 -Tree, called CVR 2 -Tree is introduced and then we discuss the calculation of lower/upper bound, and then propose the optimization technique via CVR 2 -Tree for further pruning. In addition, a search algorithm named RSVQ k algorithm is developed to support the efficient RSVQ k query. Comprehensive experiments are conducted on four geo-image datasets, and the results illustrate that our approach can address the RSVQ k problem effectively and efficiently
2′-Amino-1′-(4-chlorophenyl)-1,7′,7′-trimethyl-2,5′-dioxo-5′,6′,7′,8′-tetrahydrospiro[indoline-3,4′(1′H)-quinoline]-3′-carbonitrile dimethylformamide solvate dihydrate
In the molecule of the title compound, C26H23ClN4O2·C3H7NO·2H2O, the indole and dihydropyridine rings are planar and make a dihedral angle of 89.86 (7)°. The dihydropyridine ring forms a dihedral angle of 79.95 (7)° with the attached benzene ring. In the crystal structure, intermolecular N—H⋯O and O—H⋯O hydrogen bonds link the molecules. Intermolecular C—H⋯N and C—H⋯Cl interactions are also present
Multi-Speaker Expressive Speech Synthesis via Multiple Factors Decoupling
This paper aims to synthesize target speaker's speech with desired speaking
style and emotion by transferring the style and emotion from reference speech
recorded by other speakers. Specifically, we address this challenging problem
with a two-stage framework composed of a text-to-style-and-emotion (Text2SE)
module and a style-and-emotion-to-wave (SE2Wave) module, bridging by neural
bottleneck (BN) features. To further solve the multi-factor (speaker timbre,
speaking style and emotion) decoupling problem, we adopt the multi-label binary
vector (MBV) and mutual information (MI) minimization to respectively
discretize the extracted embeddings and disentangle these highly entangled
factors in both Text2SE and SE2Wave modules. Moreover, we introduce a
semi-supervised training strategy to leverage data from multiple speakers,
including emotion-labelled data, style-labelled data, and unlabeled data. To
better transfer the fine-grained expressiveness from references to the target
speaker in the non-parallel transfer, we introduce a reference-candidate pool
and propose an attention based reference selection approach. Extensive
experiments demonstrate the good design of our model.Comment: Submitted to ICASSP202
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