81 research outputs found
Coupled Model of Precipitates and Microsegregation During Solidification
To understand the precipitation behavior and solidification process of micro-alloyed steel, abundant thermodynamic data of pure substances were incorporated in the coupled thermodynamic model of inclusions precipitation and solutes micro-segregation during the solidification of heat-resistant steel containing cerium. The liquid inclusions Ce2xAl2ySi1−x−yOz where 0 < x < 1, 0 < y < 1−x and z = 1−x−y and their generation Gibbs free energy were first introduced to the inclusions reactions according to the Al2O3-SiO2-Ce2O3 phase diagram. Then plant trials, lab experiments and published work in the literature were taken account to valid the established model. Also, the difference of calculated results between FactSage and this model were argued. Finally, the liquid inclusions were found in the samples from experiments in the tube furnace based on the calculations by this model
Lateral response and energetics of cable-guided hoisting system with time-varying length
The lateral response, energetics and stability of the cable-guided hoisting system that differs from the rail-guided, such as elevator systems, is investigated in this paper. While the equations of motion are established by Hamilton's principle, the boundary conditions are obtained to calculate the natural frequencies with the modified velocity of wave propagation. Then, the governing equation is transformed into a set of ordinary differential equations through the Galerkin method and the rate of change in the energy is derived from the control volume viewpoint. The system frequencies, response of each order and energy characteristics are analyzed. The results show that the system frequencies first decrease, and then increase with the increase of the length and demonstrate that the modified velocity of wave propagation is reasonable by comparison of three approaches. The presented method proves to be effective to obtain the response of each order. According to Lyapunov’s second method, the rate of change in the energy indicates the cable-guided hoisting system experiences stability and instability during downward and upward movements, respectively
Seeing through the Mask: Multi-task Generative Mask Decoupling Face Recognition
The outbreak of COVID-19 pandemic make people wear masks more frequently than
ever. Current general face recognition system suffers from serious performance
degradation,when encountering occluded scenes. The potential reason is that
face features are corrupted by occlusions on key facial regions. To tackle this
problem, previous works either extract identity-related embeddings on feature
level by additional mask prediction, or restore the occluded facial part by
generative models. However, the former lacks visual results for model
interpretation, while the latter suffers from artifacts which may affect
downstream recognition. Therefore, this paper proposes a Multi-task gEnerative
mask dEcoupling face Recognition (MEER) network to jointly handle these two
tasks, which can learn occlusionirrelevant and identity-related representation
while achieving unmasked face synthesis. We first present a novel mask
decoupling module to disentangle mask and identity information, which makes the
network obtain purer identity features from visible facial components. Then, an
unmasked face is restored by a joint-training strategy, which will be further
used to refine the recognition network with an id-preserving loss. Experiments
on masked face recognition under realistic and synthetic occlusions benchmarks
demonstrate that the MEER can outperform the state-ofthe-art methods
Подходы к лечению перфорантной недостаточности у пациентов с варикозной болезнью вен нижних конечностей
ВАРИКОЗНОЕ РАСШИРЕНИЕ ВЕНКОНЕЧНОСТЬ НИЖНЯЯХИРУРГИЧЕСКИЕ ОПЕРАЦИИперфорантная недостаточност
A Survey of Face Recognition
Recent years witnessed the breakthrough of face recognition with deep
convolutional neural networks. Dozens of papers in the field of FR are
published every year. Some of them were applied in the industrial community and
played an important role in human life such as device unlock, mobile payment,
and so on. This paper provides an introduction to face recognition, including
its history, pipeline, algorithms based on conventional manually designed
features or deep learning, mainstream training, evaluation datasets, and
related applications. We have analyzed and compared state-of-the-art works as
many as possible, and also carefully designed a set of experiments to find the
effect of backbone size and data distribution. This survey is a material of the
tutorial named The Practical Face Recognition Technology in the Industrial
World in the FG2023
Microwave electrometry with multi-photon coherence in Rydberg atoms
A scheme for measurement of microwave (MW) electric field is proposed via
multi-photon coherence in Rydberg atoms. It is based on the three-photon
electromagnetically induced absorption (TPEIA) spectrum. In this process, the
multi-photon produces a narrow absorption peak, which has a larger magnitude
than the electromagnetically induced transparency (EIT) peak under the same
conditions. The TPEIA peak is sensitive to MW fields, and can be used to
measure MW electric field strength. It is interesting to find that the
magnitude of TPEIA peaks shows a linear relationship with the MW field
strength. The simulation results show that the minimum detectable strength of
the MW fields is about 1/10 that based on an common EIT effect, and the probe
sensitivity is improved by about 4 times. Furthermore, the MW sensing based on
three-photon coherence shows a broad tunability, and the scheme may be useful
for designing novel MW sensing devices.Comment: 6 pages,13 figure
Tunable ultranarrow linewidth of cavity induced by interacting dark resonances
A scheme for getting a tunable ultranarrow linewidth of a cavity due to an
embedded four-level atomic medium with double-dark resonances is proposed. It
is shown that the steep dispersion induced by double-dark resonances in the
transparency window leads to the ultranarrow transmission peak. Compared with
the case of a single-dark-resonance system, the linewidth can be narrowed even
by one order under proper conditions. Furthermore, the position of the
ultranarrow peak can be engineered by varying the intensity and detuning of the
control field.Comment: 4 pages, 5 figure
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