9,609 research outputs found
Optimizing production scheduling of steel plate hot rolling for economic load dispatch under time-of-use electricity pricing
Time-of-Use (TOU) electricity pricing provides an opportunity for industrial
users to cut electricity costs. Although many methods for Economic Load
Dispatch (ELD) under TOU pricing in continuous industrial processing have been
proposed, there are still difficulties in batch-type processing since power
load units are not directly adjustable and nonlinearly depend on production
planning and scheduling. In this paper, for hot rolling, a typical batch-type
and energy intensive process in steel industry, a production scheduling
optimization model for ELD is proposed under TOU pricing, in which the
objective is to minimize electricity costs while considering penalties caused
by jumps between adjacent slabs. A NSGA-II based multi-objective production
scheduling algorithm is developed to obtain Pareto-optimal solutions, and then
TOPSIS based multi-criteria decision-making is performed to recommend an
optimal solution to facilitate filed operation. Experimental results and
analyses show that the proposed method cuts electricity costs in production,
especially in case of allowance for penalty score increase in a certain range.
Further analyses show that the proposed method has effect on peak load
regulation of power grid.Comment: 13 pages, 6 figures, 4 table
Echocardiographic parameters versus CHA2DS2-VASc score in prediction of overall cardiac events, heart failure, and stroke in non-valvular atrial fibrillation
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 Background: Apart from stroke, atrial fibrillation (AF) is associated with higher mortality and heart failure (HF), in which risk stratification scheme is lacking. Therefore this investigation examined the prognostic value of echocardiographic predictors against CHA2DS2-VASc score in permanent non- -valvular AF (NVAF).
Methods: In 252 asymptomatic or mildly symptomatic consecutive patients with NVAF, comprehensive echocardiography was performed. Left atrial deformation parameters were also obtained by two-dimenÂsional speckle tracking echocardiography. End-points pertaining to HF deterioration, ischemic stroke and cardiac death were recorded.
Results: There were 74 cardiovascular events, including 44 deterioration of HF, 22 ischemic strokes and 8 cardiovascular deaths during an average follow-up period of 20.8 ± 13.5 months (interquartile range, 8–31 months). For prediction of overall prognosis and HF, left ventricular mass index, peak early filling velocity (E), and E to tissue Doppler mitral annular early diastolic velocity ratio (E/e’) outperÂformed CHA2DS2-VASc score in multivariate analysis, area under curve, and stepwise nested regression models. Left ventricular hypertrophy and E/e’ > 8 showed worse overall and heart-failure free survival in Kaplan-Meier curves. For prediction of ischemic stroke, the addition of E or E/e’ to CHA2DS2-VASc score provides extra prognostic value.
Conclusions: Echocardiographic parameters offer incremental value over CHA2DS2-VASc score for prediction of future cardiac events in NVAF. (Cardiol J 2018; 25, 1: 60–71
Numerical investigations on interactions between 2D/3D conical shock wave and axisymmetric boundary layer at Ma=2.2
Numerical simulation and analysis are carried out on interactions between a
2D/3D conical shock wave and an axisymmetric boundary layer with reference to
the experiment by Kussoy et al., in which the shock was generated by a 15-deg
half-angle cone in a tube at 15-deg angle of attack (AOA). Based on the RANS
equations and Menter's SST turbulence model, the present study uses the newly
developed WENO3-PRM211 scheme and the PHengLEI CFD platform for the
computations. First, computations are performed for the 3D interaction
corresponding to the conditions of the experiment by Kussoy et al., and these
are then extended to cases with AOA = 10-deg and 5-deg. For comparison, 2D
axisymmetric counterparts of the 3D interactions are investigated for cones
coaxial with the tube and having half-cone angles of 27.35-deg, 24.81-deg, and
20.96-deg. The shock wave structure, vortex structure, variable distributions,
and wall separation topology of the interaction are computed. The results show
that in 2D/3D interactions, a new Mach reflection-like event occurs and a Mach
stem-like structure is generated above the front of the separation bubble,
which differs from the model of Babinsky for 2D planar shock wave/boundary
layer interaction. A new interaction model is established to describe this
behavior. The relationship between the length of the circumferentially
unseparated region in the tube and the AOA of the cone indicates the existence
of a critical AOA at which the length is zero, and a prediction of this angle
is obtained using an empirical fit, which is verified by computation. The
occurrence of side overflow in the windward meridional plane is analyzed, and a
quantitative knowledge is obtained. To elucidate the characteristics of the 3D
interaction, the scale and structure of the vortex and the pressure and
friction force distributions are presented and compared with those of the 2D
interaction
Experimental generation of 6 dB continuous variable entanglement from a nondegenerate optical parametric amplifier
We experimentally demonstrated that the quantum correlations of amplitude and
phase quadratures between signal and idler beams produced from a non-degenerate
optical parametric amplifier (NOPA) can be significantly improved by using a
mode cleaner in the pump field and reducing the phase fluctuations in phase
locking systems. Based on the two technical improvements the quantum
entanglement measured with a two-mode homodyne detector is enhanced from ~ 4 dB
to ~ 6 dB below the quantum noise limit using the same NOPA and nonlinear
crystal.Comment: 7 pages, 5 figure
Recommending Themes for Ad Creative Design via Visual-Linguistic Representations
There is a perennial need in the online advertising industry to refresh ad
creatives, i.e., images and text used for enticing online users towards a
brand. Such refreshes are required to reduce the likelihood of ad fatigue among
online users, and to incorporate insights from other successful campaigns in
related product categories. Given a brand, to come up with themes for a new ad
is a painstaking and time consuming process for creative strategists.
Strategists typically draw inspiration from the images and text used for past
ad campaigns, as well as world knowledge on the brands. To automatically infer
ad themes via such multimodal sources of information in past ad campaigns, we
propose a theme (keyphrase) recommender system for ad creative strategists. The
theme recommender is based on aggregating results from a visual question
answering (VQA) task, which ingests the following: (i) ad images, (ii) text
associated with the ads as well as Wikipedia pages on the brands in the ads,
and (iii) questions around the ad. We leverage transformer based cross-modality
encoders to train visual-linguistic representations for our VQA task. We study
two formulations for the VQA task along the lines of classification and
ranking; via experiments on a public dataset, we show that cross-modal
representations lead to significantly better classification accuracy and
ranking precision-recall metrics. Cross-modal representations show better
performance compared to separate image and text representations. In addition,
the use of multimodal information shows a significant lift over using only
textual or visual information.Comment: 7 pages, 8 figures, 2 tables, accepted by The Web Conference 202
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