2,639 research outputs found
Effective Discriminative Feature Selection with Non-trivial Solutions
Feature selection and feature transformation, the two main ways to reduce
dimensionality, are often presented separately. In this paper, a feature
selection method is proposed by combining the popular transformation based
dimensionality reduction method Linear Discriminant Analysis (LDA) and sparsity
regularization. We impose row sparsity on the transformation matrix of LDA
through -norm regularization to achieve feature selection, and
the resultant formulation optimizes for selecting the most discriminative
features and removing the redundant ones simultaneously. The formulation is
extended to the -norm regularized case: which is more likely to
offer better sparsity when . Thus the formulation is a better
approximation to the feature selection problem. An efficient algorithm is
developed to solve the -norm based optimization problem and it is
proved that the algorithm converges when . Systematical experiments
are conducted to understand the work of the proposed method. Promising
experimental results on various types of real-world data sets demonstrate the
effectiveness of our algorithm
Lower Global Warming Potential and Higher Yield of Wet Direct-Seeded Rice in Central China
Poster Session
Pyrolysis of Low-Rank Coal: From Research to Practice
Low-rank coal (LRC), as a conventional fossil fuel, has wealth of reserves and a wide range of distribution around the world, and pyrolysis is thought to be an easy way for clean and efficient conversion of LRC. In this chapter, the characteristics and world’s reservation of LRC are introduced. Then, the chemical reactions and product formation process during pyrolysis of LRC are described. Meanwhile, how the factors, such as temperature, minerals in coal, heating rate, particle size and atmosphere, influence the pyrolysis process are discussed. Finally, three LRC pyrolysis-based polygeneration systems are illustrated for recent developments on LRC industrial practice
Moving Metric Detection and Alerting System at eBay
At eBay, there are thousands of product health metrics for different domain
teams to monitor. We built a two-phase alerting system to notify users with
actionable alerts based on anomaly detection and alert retrieval. In the first
phase, we developed an efficient anomaly detection algorithm, called Moving
Metric Detector (MMD), to identify potential alerts among metrics with
distribution agnostic criteria. In the second alert retrieval phase, we built
additional logic with feedbacks to select valid actionable alerts with
point-wise ranking model and business rules. Compared with other trend and
seasonality decomposition methods, our decomposer is faster and better to
detect anomalies in unsupervised cases. Our two-phase approach dramatically
improves alert precision and avoids alert spamming in eBay production.Comment: The work is oral presented on the AAAI-20 Workshop on Cloud
Intelligence, 202
Dynamically observing the spectra of quantum droplets in optical lattice
Optical lattice plays an important role on stability and dynamics of quantum
droplets. In this letter, we investigate the Bogoliubov excitation spectrum of
quantum droplets in optical lattice in the thermodynamic limit. We classify the
collective excitations as synchronous modes, Bloch phononic modes, and
site-density imbalanced modes. For synchronous modes, we measure the dipole
oscillation frequencies by quench dynamics with a sudden shift of the optical
lattice, and the breathing frequencies by Floquet dynamics with a periodic
change of the lattice depth. Bloch phononic modes are observable from the
Landau critical velocity of the droplets. We further discuss the instability
induced by the site-dependent density fluctuations, and calculate the critical
filling of atoms where the growth of lattice vacancy breaks down the
translational symmetry of the system. This work makes essential steps towards
measuring the excitation spectrum and understanding the superfluid nature of
quantum droplets in optical lattice.Comment: 5 figure
Ghost translation
Artificial intelligence has recently been widely used in computational
imaging. The deep neural network (DNN) improves the signal-to-noise ratio of
the retrieved images, whose quality is otherwise corrupted due to the low
sampling ratio or noisy environments. This work proposes a new computational
imaging scheme based on the sequence transduction mechanism with the
transformer network. The simulation database assists the network in achieving
signal translation ability. The experimental single-pixel detector's signal
will be `translated' into a 2D image in an end-to-end manner. High-quality
images with no background noise can be retrieved at a sampling ratio as low as
2%. The illumination patterns can be either well-designed speckle patterns for
sub-Nyquist imaging or random speckle patterns. Moreover, our method is robust
to noise interference. This translation mechanism opens a new direction for
DNN-assisted ghost imaging and can be used in various computational imaging
scenarios.Comment: 10 pages, 8 figure
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