1,101 research outputs found
Phenotype-based and Self-learning Inter-individual Sleep Apnea Screening with a Level IV Monitoring System
Purpose: We propose a phenotype-based artificial intelligence system that can
self-learn and is accurate for screening purposes, and test it on a Level IV
monitoring system. Methods: Based on the physiological knowledge, we
hypothesize that the phenotype information will allow us to find subjects from
a well-annotated database that share similar sleep apnea patterns. Therefore,
for a new-arriving subject, we can establish a prediction model from the
existing database that is adaptive to the subject. We test the proposed
algorithm on a database consisting of 62 subjects with the signals recorded
from a Level IV wearable device measuring the thoracic and abdominal movements
and the SpO2. Results: With the leave-one cross validation, the accuracy of the
proposed algorithm to screen subjects with an apnea-hypopnea index greater or
equal to 15 is 93.6%, the positive likelihood ratio is 6.8, and the negative
likelihood ratio is 0.03. Conclusion: The results confirm the hypothesis and
show that the proposed algorithm has great potential to screen patients with
SAS
Enhancing thermoelectric figure-of-merit by low-dimensional electrical transport in phonon-glass crystals
Low-dimensional electronic and glassy phononic transport are two important
ingredients of highly-efficient thermoelectric material, from which two
branches of the thermoelectric research emerge. One focuses on controlling
electronic transport in the low dimension, while the other on multiscale phonon
engineering in the bulk. Recent work has benefited much from combining these
two approaches, e.g., phonon engineering in low-dimensional materials. Here, we
propose to employ the low-dimensional electronic structure in bulk phonon-glass
crystal as an alternative way to increase the thermoelectric efficiency.
Through first-principles electronic structure calculation and classical
molecular dynamics simulation, we show that the - stacking
Bis-Dithienothiophene molecular crystal is a natural candidate for such an
approach. This is determined by the nature of its chemical bonding. Without any
optimization of the material parameter, we obtain a maximum room-temperature
figure of merit, , of at optimal doping, thus validating our idea.Comment: Nano Lett.201
Synthesis of thioesters through copper-catalyzed coupling of aldehydeswith thiols in water
Copper-catalyzed CâS bond formation between aldehydes and thiols in the presence of TBHP as an oxidant is described. Functional groups including chloro, trifluoromethyl, bromo, iodo, nitrile, ester and thiophene are all tolerated by the reaction conditions employed. This reaction is performed in water without the use of a surfactant. Both aryl and alkyl aldehydes couple suitably with aryl- and alkyl thiols, affording the corresponding thioesters in moderate to good yields
Pokemon Go: A Study on Fit in Virtual-Reality Integration
Augmented reality has become a trend today. The effects of PokĂ©mon Go, the most popular smart phone game recently, on medicine and tourism have been explored in many studies. However, few studies on the cognition and the consistence between emotions and the integration of virtuality (the PokĂ©mon projected in the game) and reality (information quality) have been done. With the Stimulus-Organism-Response (S-O-R) model as the framework, this study aims to explore the fit (cognitive/emotional) and reactions (user satisfaction) of the user in the virtuality-reality integration. According to the findings of this study, information quality and virtual features have significant influence on cognitive and emotional fit and emotional fit has significant influence on user satisfaction; however, cognitive fit doesnât have significant influence on user satisfaction. It has been found that the user pays much attention to his/her feelings when playing games. Therefore, we should get acquainted with the types and emotions of game players in addition to maintaining the quality of games
The First and Second Order Asymptotics of Covert Communication over AWGN Channels
This paper investigates the asymptotics of the maximal throughput of
communication over AWGN channels by channel uses under a covert constraint
in terms of an upper bound of Kullback-Leibler divergence (KL
divergence). It is shown that the first and second order asymptotics of the
maximal throughput are and
, respectively.
The technique we use in the achievability is quasi--neighborhood
notion from information geometry. We prove that if the generating distribution
of the codebook is close to Dirac measure in the weak sense, then the
corresponding output distribution at the adversary satisfies covert constraint
in terms of most common divergences. This helps link the local differential
geometry of the distribution of noise with covert constraint. For the converse,
the optimality of Gaussian distribution for minimizing KL divergence under
second order moment constraint is extended from dimension to dimension .
It helps to establish the upper bound on the average power of the code to
satisfy the covert constraint, which further leads to the direct converse bound
in terms of covert metric
Existence theorems for a crystal surface model involving the p-Laplace operator
The manufacturing of crystal films lies at the heart of modern
nanotechnology. How to accurately predict the motion of a crystal surface is of
fundamental importance. Many continuum models have been developed for this
purpose, including a number of PDE models, which are often obtained as the
continuum limit of a family of kinetic Monte Carlo models of crystal surface
relaxation that includes both the solid-on-solid and discrete Gaussian models.
In this paper we offer an analytical perspective into some of these models. To
be specific, we study the existence of a weak solution to the boundary value
problem for the equation - \Delta e^{-\mbox{div}\left(|\nabla u|^{p-2}\nabla
u\right)}+au=f, where are given numbers and is a given
function. This problem is derived from a crystal surface model proposed by
J.L.~Marzuola and J.~Weare (2013 Physical Review, E 88, 032403). The
mathematical challenge is due to the fact that the principal term in our
equation is an exponential function of a p-Laplacian. Existence of a
suitably-defined weak solution is established under the assumptions that
, and . Our investigations reveal that the
key to our existence assertion is how to control the set where
-\mbox{div}\left(|\nabla u|^{p-2}\nabla u\right) is
Single-Image HDR Reconstruction by Learning to Reverse the Camera Pipeline
Recovering a high dynamic range (HDR) image from a single low dynamic range
(LDR) input image is challenging due to missing details in under-/over-exposed
regions caused by quantization and saturation of camera sensors. In contrast to
existing learning-based methods, our core idea is to incorporate the domain
knowledge of the LDR image formation pipeline into our model. We model the
HDRto-LDR image formation pipeline as the (1) dynamic range clipping, (2)
non-linear mapping from a camera response function, and (3) quantization. We
then propose to learn three specialized CNNs to reverse these steps. By
decomposing the problem into specific sub-tasks, we impose effective physical
constraints to facilitate the training of individual sub-networks. Finally, we
jointly fine-tune the entire model end-to-end to reduce error accumulation.
With extensive quantitative and qualitative experiments on diverse image
datasets, we demonstrate that the proposed method performs favorably against
state-of-the-art single-image HDR reconstruction algorithms.Comment: CVPR 2020. Project page:
https://www.cmlab.csie.ntu.edu.tw/~yulunliu/SingleHDR Code:
https://github.com/alex04072000/SingleHD
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