641 research outputs found
Aesthetically Relevant Image Captioning
Image aesthetic quality assessment (AQA) aims to assign numerical aesthetic
ratings to images whilst image aesthetic captioning (IAC) aims to generate
textual descriptions of the aesthetic aspects of images. In this paper, we
study image AQA and IAC together and present a new IAC method termed
Aesthetically Relevant Image Captioning (ARIC). Based on the observation that
most textual comments of an image are about objects and their interactions
rather than aspects of aesthetics, we first introduce the concept of Aesthetic
Relevance Score (ARS) of a sentence and have developed a model to automatically
label a sentence with its ARS. We then use the ARS to design the ARIC model
which includes an ARS weighted IAC loss function and an ARS based diverse
aesthetic caption selector (DACS). We present extensive experimental results to
show the soundness of the ARS concept and the effectiveness of the ARIC model
by demonstrating that texts with higher ARS's can predict the aesthetic ratings
more accurately and that the new ARIC model can generate more accurate,
aesthetically more relevant and more diverse image captions. Furthermore, a
large new research database containing 510K images with over 5 million comments
and 350K aesthetic scores, and code for implementing ARIC are available at
https://github.com/PengZai/ARIC.Comment: Aceepted by AAAI2023. Code and results available at
https://github.com/PengZai/ARI
Finite element modeling and active vibration control of high-speed spinning flexible beam
Finite element modeling and active vibration control of a high-speed spinning flexible coupled electromechanical beam is investigated using a first-order approximation coupling (FOAC) model. Due to centrifugal forces caused by eccentricity in a spinning flexible beam, there exists coupling between axial and transverse vibration modes. The partial differential equations of motion of the beam governing this coupling are derived using Hamilton’s principle based on an FOAC model, and a finite element method for discretization is given. It is observed that the zero-order approximate coupling (ZOAC) model is valid for dynamic description of the flexible beam spinning at low speeds, but no longer valid at high speeds. However, the validity of FOAC model is confirmed at different speeds. Piezoelectric elements for active vibration control of the spinning flexible beam are analyzed and a velocity feedback controller is proposed. Simulation results demonstrate good performance of the proposed velocity feedback controller
Super-resolving Compressed Images via Parallel and Series Integration of Artifact Reduction and Resolution Enhancement
In this paper, we propose a novel compressed image super resolution (CISR)
framework based on parallel and series integration of artifact removal and
resolution enhancement. Based on maximum a posterior inference for estimating a
clean low-resolution (LR) input image and a clean high resolution (HR) output
image from down-sampled and compressed observations, we have designed a CISR
architecture consisting of two deep neural network modules: the artifact
reduction module (ARM) and resolution enhancement module (REM). ARM and REM
work in parallel with both taking the compressed LR image as their inputs,
while they also work in series with REM taking the output of ARM as one of its
inputs and ARM taking the output of REM as its other input. A unique property
of our CSIR system is that a single trained model is able to super-resolve LR
images compressed by different methods to various qualities. This is achieved
by exploiting deep neural net-works capacity for handling image degradations,
and the parallel and series connections between ARM and REM to reduce the
dependency on specific degradations. ARM and REM are trained simultaneously by
the deep unfolding technique. Experiments are conducted on a mixture of JPEG
and WebP compressed images without a priori knowledge of the compression type
and com-pression factor. Visual and quantitative comparisons demonstrate the
superiority of our method over state-of-the-art super resolu-tion methods.Code
link: https://github.com/luohongming/CISR_PS
Current-Induced Dynamics and Chaos of Antiferromagnetic Bimerons
A magnetic bimeron is a topologically non-trivial spin texture carrying an
integer topological charge, which can be regarded as the counterpart of
skyrmion in easy-plane magnets. The controllable creation and manipulation of
bimerons are crucial for practical applications based on topological spin
textures. Here, we analytically and numerically study the dynamics of an
antiferromagnetic bimeron driven by a spin current. Numerical simulations
demonstrate that the spin current can create an isolated bimeron in the
antiferromagnetic thin film via the damping-like spin torque. The spin current
can also effectively drive the antiferromagnetic bimeron without a transverse
drift. The steady motion of an antiferromagnetic bimeron is analytically
derived and is in good agreement with the simulation results. Also, we find
that the alternating-current-induced motion of the antiferromagnetic bimeron
can be described by the Duffing equation due to the presence of the nonlinear
boundary-induced force. The associated chaotic behavior of the bimeron is
analyzed in terms of the Lyapunov exponents. Our results demonstrate the
inertial dynamics of an antiferromagnetic bimeron, and may provide useful
guidelines for building future bimeron-based spintronic devices.Comment: 6 pages, 4 figure
Back-action Induced Non-equilibrium Effect in Electron Charge Counting Statistics
We report our study of the real-time charge counting statistics measured by a
quantum point contact (QPC) coupled to a single quantum dot (QD) under
different back-action strength. By tuning the QD-QPC coupling or QPC bias, we
controlled the QPC back-action which drives the QD electrons out of thermal
equilibrium. The random telegraph signal (RTS) statistics showed strong and
tunable non-thermal-equilibrium saturation effect, which can be quantitatively
characterized as a back-action induced tunneling out rate. We found that the
QD-QPC coupling and QPC bias voltage played different roles on the back-action
strength and cut-off energy.Comment: 4 pages, 4 figures, 1 tabl
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