6,288 research outputs found
The Zeros of Orthogonal Polynomials for Jacobi-Exponential Weights
This paper gives the estimates of the zeros of orthogonal polynomials for Jacobi-exponential weights
Adversarial Feature Stacking for Accurate and Robust Predictions
Deep Neural Networks (DNNs) have achieved remarkable performance on a variety
of applications but are extremely vulnerable to adversarial perturbation. To
address this issue, various defense methods have been proposed to enhance model
robustness. Unfortunately, the most representative and promising methods, such
as adversarial training and its variants, usually degrade model accuracy on
benign samples, limiting practical utility. This indicates that it is difficult
to extract both robust and accurate features using a single network under
certain conditions, such as limited training data, resulting in a trade-off
between accuracy and robustness. To tackle this problem, we propose an
Adversarial Feature Stacking (AFS) model that can jointly take advantage of
features with varied levels of robustness and accuracy, thus significantly
alleviating the aforementioned trade-off. Specifically, we adopt multiple
networks adversarially trained with different perturbation budgets to extract
either more robust features or more accurate features. These features are then
fused by a learnable merger to give final predictions. We evaluate the AFS
model on CIFAR-10 and CIFAR-100 datasets with strong adaptive attack methods,
which significantly advances the state-of-the-art in terms of the trade-off.
Without extra training data, the AFS model achieves a benign accuracy
improvement of 6% on CIFAR-10 and 9% on CIFAR-100 with comparable or even
stronger robustness than the state-of-the-art adversarial training methods.
This work demonstrates the feasibility to obtain both accurate and robust
models under the circumstances of limited training data
Phase diagram and exotic spin-spin correlations of anisotropic Ising model on the Sierpi\'nski gasket
The anisotropic antiferromagnetic Ising model on the fractal Sierpi\'{n}ski
gasket is intensively studied, and a number of exotic properties are disclosed.
The ground state phase diagram in the plane of magnetic field-interaction of
the system is obtained. The thermodynamic properties of the three plateau
phases are probed by exploring the temperature-dependence of magnetization,
specific heat, susceptibility and spin-spin correlations. No phase transitions
are observed in this model. In the absence of a magnetic field, the unusual
temperature dependence of the spin correlation length is obtained with JJ, and an interesting crossover behavior between different
phases at JJ is unveiled, whose dynamics can be described by the
JJ-dependence of the specific heat, susceptibility and spin
correlation functions. The exotic spin-spin correlation patterns that share the
same special rotational symmetry as that of the Sierpi\'{n}ski gasket are
obtained in both the plateau disordered phase and the plateau
partially ordered ferrimagnetic phase. Moreover, a quantum scheme is formulated
to study the thermodynamics of the fractal Sierpi\'{n}ski gasket with
Heisenberg interactions. We find that the unusual temperature dependence of the
correlation length remains intact in a small quantum fluctuation.Comment: 9 pages, 12 figure
Personalized compression therapeutic textiles: digital design, development, and biomechanical evaluation
Physical-based external compression medical modalities could provide sustainable interfacial pressure dosages for daily healthcare prophylaxis and clinic treatment of chronic venous disease (CVD). However, conventional ready-made compression therapeutic textiles (CTs) with improper morphologies and ill-fitting of pressure exertions frequently limit patient compliance in practical application. Therefore, the present study fabricated the personalized CTs for various subjects through the proposed comprehensive manufacturing system. The individual geometric dimensions and morphologic profiles of lower extremities were characterized according to three-dimensional (3D) body scanning and reverse engineering technologies. Through body anthropometric analysis and pressure optimization, the knitting yarn and machinery variables were determined as the digital design strategies for 3D seamless fabrication of CTs. Next, to visually simulate the generated pressure mappings of developed CTs, the subject-specific 3D finite element (FE) CT-leg modelings with high accuracy and acceptability (pressure prediction error ratio: 11.00% ± 7.78%) were established based on the constructed lower limb models and determined tissue stiffness. Moreover, through the actual in vivo trials, the prepared customized CTs efficiently (Sig. <0.05; ρ = 0.97) distributed the expected pressure requirements referring to the prescribed compression magnitudes (pressure error ratio: 10.08% ± 7.75%). Furthermore, the movement abilities and comfortable perceptions were evaluated subjectively for the ergonomic wearing comfort (EWC) assessments. Thus, this study promotes the precise pressure management and clinical efficacy for targeted users and leads an operable development approach for related medical biomaterials in compression therapy
Antitumor Efficacy and Mechanism in Hepatoma H22-Bearing Mice of Brucea javanica
Brucea javanica is a traditional herbal medicine in China, and its antitumor activities are of research interest. Brucea javanica oil, extracted with ether and refined with 10% ethyl alcohol from Brucea javanica seed, was used to treat hepatoma H22-bearing mice in this study. The antitumor effect and probable mechanisms of the extracted Brucea javanica oil were studied in H22-bearing mice by WBC count, GOT, GPT levels, and western blotting. The H22 tumor inhibition ratio of 0.5, 1, and 1.5 g/kg bw Brucea javanica oil were 15.64%, 23.87%, and 38.27%. Brucea javanica oil could inhibit the involution of thymus induced by H22 tumor-bearing, but it could not inhibit the augmentation of spleen and liver. Brucea javanica oil could decrease the levels of WBC count and GOT and GPT in H22-bearing mice. The protein levels of GAPDH, Akt, TGF-β1, and α-SMA in tumor tissues decreased after being treated with Brucea javanica oil. Disturbing energy metabolism and neoplastic hyperplasia controlled by Akt and immunoregulation activity were its probable antitumor mechanisms in hepatoma H22-bearing mice
Planar carbon nanotube-graphene hybrid films for high-performance broadband photodetectors
Graphene has emerged as a promising material for photonic applications
fuelled by its superior electronic and optical properties. However, the
photoresponsivity is limited by the low absorption cross section and ultrafast
recombination rates of photoexcited carriers. Here we demonstrate a
photoconductive gain of 10 electrons per photon in a carbon
nanotube-graphene one dimensional-two dimensional hybrid due to efficient
photocarriers generation and transport within the nanostructure. A broadband
photodetector (covering 400 nm to 1550 nm) based on such hybrid films is
fabricated with a high photoresponsivity of more than 100 AW and a fast
response time of approximately 100 {\mu}s. The combination of ultra-broad
bandwidth, high responsivities and fast operating speeds affords new
opportunities for facile and scalable fabrication of all-carbon optoelectronic
devices.Comment: 21 pages, 3 figure
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