4,543 research outputs found
A Robust Interferometry Against Imperfections Base on Weak Value Amplification
The optical interferometry has been widely used in various high precision
applications. Usually, the minimum precision of an interferometry is limited by
various technique noises in practice. To suppress such kind of noises, we
propose a novel scheme, which combines the weak measurement with the standard
interferometry. The proposed scheme dramatically outperforms the standard
interferometry in the signal noise ratio and the robustness against noises
caused by the optical elements' reflections and the offset fluctuation between
two paths. A proof-of-principle experiment is demonstrated to validate the
amplification theory.Comment: 7 pages, 11 figures. submitted to PR
A Two-Dimensional CA Traffic Model with Dynamic Route Choices Between Residence and Workplace
The Biham, Middleton and Levine (BML) model is extended to describe dynamic
route choices between the residence and workplace in cities. The traffic
dynamic in the city with a single workplace is studied from the velocity
diagram, arrival time probability distribution, destination arrival rate and
convergence time. The city with double workplaces is also investigated to
compared with a single workplace within the framework of four modes of urban
growth. The transitional region is found in the velocity diagrams where the
system undergoes a continuous transition from a moving phase to a completely
jamming phase. We perform a finite-size scaling analysis of the critical
density from a statistical point of view and the order parameter of this
jamming transition is estimated. It is also found that statistical properties
of urban traffic are greatly influenced by the urban area, workplace area and
urban layout.Comment: 18 pages, 13 figure
Characterizations of -well-posedness for parametric quasivariational inequalities defined by bifunctions
The purpose of this paper is to investigate the
well-posedness issue of parametric quasivariational inequalities
defined by bifunctions. We generalize the concept of
-well-posedness to parametric quasivariational inequalities
having a unique solution and derive some characterizations of
-well-posedness. The corresponding concepts of
-well-posedness in the generalized sense are also introduced
and investigated for the problems having more than one solution.
Finally, we give some sufficient conditions for
-well-posedness of parametric quasivariational inequalities
Strong Transferable Adversarial Attacks via Ensembled Asymptotically Normal Distribution Learning
Strong adversarial examples are crucial for evaluating and enhancing the
robustness of deep neural networks. However, the performance of popular attacks
is usually sensitive, for instance, to minor image transformations, stemming
from limited information -- typically only one input example, a handful of
white-box source models, and undefined defense strategies. Hence, the crafted
adversarial examples are prone to overfit the source model, which hampers their
transferability to unknown architectures. In this paper, we propose an approach
named Multiple Asymptotically Normal Distribution Attacks (MultiANDA) which
explicitly characterize adversarial perturbations from a learned distribution.
Specifically, we approximate the posterior distribution over the perturbations
by taking advantage of the asymptotic normality property of stochastic gradient
ascent (SGA), then employ the deep ensemble strategy as an effective proxy for
Bayesian marginalization in this process, aiming to estimate a mixture of
Gaussians that facilitates a more thorough exploration of the potential
optimization space. The approximated posterior essentially describes the
stationary distribution of SGA iterations, which captures the geometric
information around the local optimum. Thus, MultiANDA allows drawing an
unlimited number of adversarial perturbations for each input and reliably
maintains the transferability. Our proposed method outperforms ten
state-of-the-art black-box attacks on deep learning models with or without
defenses through extensive experiments on seven normally trained and seven
defense models
A quartic system and a quintic system with fine focus of order 18
AbstractBy using an effective complex algorithm to calculate the Lyapunov constants of polynomial systems En: z˙=iz+Rn(z,z¯), where Rn is a homogeneous polynomial of degree n, in this note we construct two concrete examples, E4 and E5, such that in both cases, the corresponding orders of fine focus can be as high as 18. The systems are given, respectively, by the following ordinary differential equations:E4:z˙=iz+2iz4+izz¯3+5227820723eiθz¯4, where θ∉{kπ±π6,kπ+π2,k∈Z}, andE5:z˙=iz+3z5+20(c+3)9c2−15z4z¯+zz¯4+20(c+3)c29c2−15z¯5, where c is the root between (−3,−5/3) of the equation4155c6−10716c5−63285c4−18070c3+168075c2+205450c+60375=0
Protective effect of liquiritin on corticosterone-induced neurotoxicity in PC12 cells
Purpose: To determine the protective effects of liquiritin on corticosterone-induced neurotoxicity in rat pheochromocytoma (PC12) cells.Methods: Neurotoxicity in PC12 cells was induced by different concentrations of corticosterone. Proliferation of PC12 cells was evaluated using CCK8 assay kits, while apoptosis was determined by flow cytometry.Results: The results indicate that corticosterone inhibited the proliferation of PC12 cells time- and dosedependently. The inhibitory effect (0.2 mM) was ameliorated by liquiritin. Furthermore, the cell apoptosis rate and protein level of caspase 3 in PC12 cells induced by corticosterone were ameliorated by liquiritin (1 and 2 mg/mL) treatment. Moreover, the protective effect of liquiritin (2 mg/mL) on corticosterone induced neurotoxicity in PC12 cells was weakened by K252a (the specific TrkB inhibitor) treatment. In addition, the protein level of brain-derived neurotrophic factor (BDNF) and (tyrosine-kinase receptor) TrkB showed a reverse trend to caspase 3.Conclusion: Liquiritin shows protective effects against neurotoxicity induced by corticosterone in PC12 cells, and these effects are exerted via up-regulating BDNF/TrkB signaling.Keywords: Liquiritin, Antidepressant, Corticosterone, Neuroprotection, PC12 cells, BDNF/TrkB signalin
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