5,584 research outputs found
K-quantum Nonlinear Jaynes-Cummings Model in Two Trapped Ions
A k-quantum nonlinear Jaynes-Cummings model for two trapped ions interacting
with laser beams resonant to k-th red side-band of center-of-mass mode, far
from Lamb-Dicke regime, has been obtained. The exact analytic solution showed
the existence of quantum collapses and revivals of the occupation of two atoms.Comment: 8 pages, 3 figure
SOCIAL COMMERCE: THE CRITICAL ROLE OF ARGUMENT STRENGTH AND SOURCE DYNAMISM OF EWOM
Due to the increasing popularity of social media, social commerce has been emerging as a new form of e-commerce. As a driving force of the popularity and growth of social commerce, electronic wordof-mouth (eWOM) plays an important role during the process of consumers’ purchase decision making in social commerce. There are adequate studies that have offered a broad view on what makes the helpfulness perception of eWOM. However, little research has investigated the effect of argument strength and source dynamism of eWOM. Drawing on Stimulus–Organism–Response (S–O–R) model and Elaboration Likelihood Model (ELM), an integrated research model is proposed and tries to explore the impact of argument strength and source dynamism of eWOM on consumers’ affective response and cognitive response and how do they affect the formation of consumers’ purchasing intention. We expect that our study can make a contribution to theoretical development and provide some guidance for retailers to carry out a better management strategy of eWOM
Quantum-State Engineering of Multiple Trapped Ions for Center-of-Mass Mode
We propose a scheme to generate a superposition with arbitrary coefficients
on a line in phase space for the center-of-mass vibrational mode of N ions by
means of isolating all other spectator vibrational modes from the
center-of-mass mode. It can be viewed as the generation of previous methods for
preparing motional states of one ion. For large number of ions, we need only
one cyclic operatin to generate such a superposition of many coherent states.Comment: 14 pages, revte
Mean-variance hybrid portfolio optimization with quantile-based risk measure
This paper addresses the importance of incorporating various risk measures in
portfolio management and proposes a dynamic hybrid portfolio optimization model
that combines the spectral risk measure and the Value-at-Risk in the
mean-variance formulation. By utilizing the quantile optimization technique and
martingale representation, we offer a solution framework for these issues and
also develop a closed-form portfolio policy when all market parameters are
deterministic. Our hybrid model outperforms the classical continuous-time
mean-variance portfolio policy by allocating a higher position of the risky
asset in favorable market states and a less risky asset in unfavorable market
states. This desirable property leads to promising numerical experiment
results, including improved Sortino ratio and reduced downside risk compared to
the benchmark models
Boosted ab initio Cryo-EM 3D Reconstruction with ACE-EM
The central problem in cryo-electron microscopy (cryo-EM) is to recover the
3D structure from noisy 2D projection images which requires estimating the
missing projection angles (poses). Recent methods attempted to solve the 3D
reconstruction problem with the autoencoder architecture, which suffers from
the latent vector space sampling problem and frequently produces suboptimal
pose inferences and inferior 3D reconstructions. Here we present an improved
autoencoder architecture called ACE (Asymmetric Complementary autoEncoder),
based on which we designed the ACE-EM method for cryo-EM 3D reconstructions.
Compared to previous methods, ACE-EM reached higher pose space coverage within
the same training time and boosted the reconstruction performance regardless of
the choice of decoders. With this method, the Nyquist resolution (highest
possible resolution) was reached for 3D reconstructions of both simulated and
experimental cryo-EM datasets. Furthermore, ACE-EM is the only amortized
inference method that reached the Nyquist resolution
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