70 research outputs found
Incremental Learning from Scratch for Task-Oriented Dialogue Systems
Clarifying user needs is essential for existing task-oriented dialogue
systems. However, in real-world applications, developers can never guarantee
that all possible user demands are taken into account in the design phase.
Consequently, existing systems will break down when encountering unconsidered
user needs. To address this problem, we propose a novel incremental learning
framework to design task-oriented dialogue systems, or for short Incremental
Dialogue System (IDS), without pre-defining the exhaustive list of user needs.
Specifically, we introduce an uncertainty estimation module to evaluate the
confidence of giving correct responses. If there is high confidence, IDS will
provide responses to users. Otherwise, humans will be involved in the dialogue
process, and IDS can learn from human intervention through an online learning
module. To evaluate our method, we propose a new dataset which simulates
unanticipated user needs in the deployment stage. Experiments show that IDS is
robust to unconsidered user actions, and can update itself online by smartly
selecting only the most effective training data, and hence attains better
performance with less annotation cost.Comment: ACL201
A Survey on Approximate Multiplier Designs for Energy Efficiency: From Algorithms to Circuits
Given the stringent requirements of energy efficiency for Internet-of-Things
edge devices, approximate multipliers, as a basic component of many processors
and accelerators, have been constantly proposed and studied for decades,
especially in error-resilient applications. The computation error and energy
efficiency largely depend on how and where the approximation is introduced into
a design. Thus, this article aims to provide a comprehensive review of the
approximation techniques in multiplier designs ranging from algorithms and
architectures to circuits. We have implemented representative approximate
multiplier designs in each category to understand the impact of the design
techniques on accuracy and efficiency. The designs can then be effectively
deployed in high-level applications, such as machine learning, to gain energy
efficiency at the cost of slight accuracy loss.Comment: 38 pages, 37 figure
A reconfigurable stochastic architecture for highly reliable computing
Mounting concerns over variability, defects and noise motivate a new approach for integrated circuits: the design of stochastic logic, that is to say, digital circuitry that operates on probabilistic signals, and so can cope with errors and uncertainty. Techniques for prob-abilistic analysis are well established. We advocate a strategy for synthesis. In this paper, we present a reconfigurable architecture that implements the computation of arbitrary continuous functions with stochastic logic. We analyze the sources of error: approxima-tion, quantization, and random fluctuations. We demonstrate the ef-fectiveness of our method on a collection of benchmarks for image processing. Synthesis trials show that our stochastic architecture requires less area than conventional hardware implementations. It achieves a large speed up compared to software conventional im-plementations. Most importantly, it is much more tolerant of soft errors (bit flips) than these deterministic implementations
Time-Reversal-Even Nonlinear Current Induced Spin Polarization
We propose a time-reversal-even spin generation in second order of electric
fields, which dominates the current induced spin polarization in a wide class
of centrosymmetric nonmagnetic materials, and leads to a novel nonlinear
spin-orbit torque in magnets. We reveal a quantum origin of this effect from
the momentum space dipole of the anomalous spin polarizability.
First-principles calculations predict sizable spin generations in several
nonmagnetic hcp metals, in monolayer TiTe, and in ferromagnetic monolayer
MnSe, which can be detected in experiment. Our work opens up the broad
vista of nonlinear spintronics in both nonmagnetic and magnetic systems.Comment: 4 pages, 2 figure
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