1,092 research outputs found
Can Online Learning Promote Educational Equity? An Empirical Study on the āDigital Divideā in Online Learning of Primary and Secondary Students During the Epidemic
The whole world including China has experienced a large-scale practice of online teaching during the COVID-19 pandemic. As a result, ādigital divideā induced by online learning has aroused wide concerns of the public. Recently, a study published in Journal of Schooling Studies sampled 508 students from 15 primary and secondary schools in Henan Province to analyze the influence of urban vs rural, school, and social class differences on online learning of primary and secondary students, using binary logistic regression model
HAQ: Hardware-Aware Automated Quantization with Mixed Precision
Model quantization is a widely used technique to compress and accelerate deep
neural network (DNN) inference. Emergent DNN hardware accelerators begin to
support mixed precision (1-8 bits) to further improve the computation
efficiency, which raises a great challenge to find the optimal bitwidth for
each layer: it requires domain experts to explore the vast design space trading
off among accuracy, latency, energy, and model size, which is both
time-consuming and sub-optimal. Conventional quantization algorithm ignores the
different hardware architectures and quantizes all the layers in a uniform way.
In this paper, we introduce the Hardware-Aware Automated Quantization (HAQ)
framework which leverages the reinforcement learning to automatically determine
the quantization policy, and we take the hardware accelerator's feedback in the
design loop. Rather than relying on proxy signals such as FLOPs and model size,
we employ a hardware simulator to generate direct feedback signals (latency and
energy) to the RL agent. Compared with conventional methods, our framework is
fully automated and can specialize the quantization policy for different neural
network architectures and hardware architectures. Our framework effectively
reduced the latency by 1.4-1.95x and the energy consumption by 1.9x with
negligible loss of accuracy compared with the fixed bitwidth (8 bits)
quantization. Our framework reveals that the optimal policies on different
hardware architectures (i.e., edge and cloud architectures) under different
resource constraints (i.e., latency, energy and model size) are drastically
different. We interpreted the implication of different quantization policies,
which offer insights for both neural network architecture design and hardware
architecture design.Comment: CVPR 2019. The first three authors contributed equally to this work.
Project page: https://hanlab.mit.edu/projects/haq
Prediction of the Size Distributions of Methanol-Ethanol Clusters Detected in VUV Laser/Time-of-flight Mass Spectrometry
The size distributions and geometries of vapor clusters equilibrated with methanolāethanol (MeāEt) liquid mixtures were recently studied by vacuum ultraviolet (VUV) laser time-of-flight (TOF) mass spectrometry and density functional theory (DFT) calculations (Liu, Y.; Consta, S.; Ogeer, F.; Shi, Y. J.; Lipson, R. H. Can. J. Chem. 2007, 85, 843ā852). On the basis of the mass spectra recorded, it was concluded that the formation of neutral tetramers is particularly prominent. Here we develop grand canonical Monte Carlo (GCMC) and molecular dynamics (MD) frameworks to compute cluster size distributions in vapor mixtures that allow a direct comparison with experimental mass spectra. Using the all-atom optimized potential for liquid simulations (OPLS-AA) force field, we systematically examined the neutral cluster size distributions as functions of pressure and temperature. These neutral cluster distributions were then used to derive ionized cluster distributions to compare directly with the experiments. The simulations suggest that supersaturation at 12 to 16 times the equilibrium vapor pressure at 298 K or supercooling at temperature 240 to 260 K at the equilibrium vapor pressure can lead to the relatively abundant tetramer population observed in the experiments. Our simulations capture the most distinct features observed in the experimental TOF mass spectra: Et3H+ at m/z = 139 in the vapor corresponding to 10:90% MeāEt liquid mixture and Me3H+ at m/z = 97 in the vapors corresponding to 50:50% and 90:10% MeāEt liquid mixtures. The hybrid GCMC scheme developed in this work extends the capability of studying the size distributions of neat clusters to mixed species and provides a useful tool for studying environmentally important systems such as atmospheric aerosols
Learning to Prove Trigonometric Identities
Automatic theorem proving with deep learning methods has attracted attentions
recently. In this paper, we construct an automatic proof system for
trigonometric identities. We define the normalized form of trigonometric
identities, design a set of rules for the proof and put forward a method which
can generate theoretically infinite trigonometric identities. Our goal is not
only to complete the proof, but to complete the proof in as few steps as
possible. For this reason, we design a model to learn proof data generated by
random BFS (rBFS), and it is proved theoretically and experimentally that the
model can outperform rBFS after a simple imitation learning. After further
improvement through reinforcement learning, we get AutoTrig, which can give
proof steps for identities in almost as short steps as BFS (theoretically
shortest method), with a time cost of only one-thousandth. In addition,
AutoTrig also beats Sympy, Matlab and human in the synthetic dataset, and
performs well in many generalization tasks
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