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Towards the transferable audio adversarial attack via ensemble methods

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Cybersecurity 2025年第1期8卷 86-102页

作者： Feng Guo Zheng Sun Yuxuan Chen Lei Ju School of Cyber Science and Technology Shandong UniversityQingdaoChina Quancheng Laboratory QCLJinanChina

In recent years,deep learning(DL)models have achieved signifcant progress in many domains,such as autonomous driving,facial recognition,and speech ***,the vulnerability of deep learning models to adversarial attacks has raised serious concerns in the community because of their insufcient robustness and ***,transferable attacks have become a prominent method for black-box *** this work,we explore the potential factors that impact adversarial examples(AEs)transferability in DL-based speech *** also discuss the vulnerability of diferent DL systems and the irregular nature of decision *** results show a remarkable diference in the transferability of AEs between speech and images,with the data relevance being low in images but opposite in speech *** by dropout-based ensemble approaches,we propose random gradient ensembles and dynamic gradient-weighted ensembles,and we evaluate the impact of ensembles on the transferability of *** results show that the AEs created by both approaches are valid for transfer to the black box API.

关键词： Adversarial attacks Dynamic gradient weighting Transferability Ensemble methods

On the transverse-traceless gauge condition when matter is presented

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Communications in Theoretical Physics 2025年第3期77卷 94-100页

作者： Yadong Xue Xiaokai He Zhoujian Cao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410205China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

The transverse-traceless gauge condition is an important concept in the theory of gravitational *** is well known that a vacuum is one of the key conditions to guarantee the existence of the transverse-traceless *** it is thin,the interstellar medium is ubiquitous in the ***,it is important to understand the concept of gravitational waves when matter is ***-Metzner-Sachs theory has solved the gauge problem related to gravitational *** it does not help with cases when the gravitational wave propagates in *** paper discusses possible extensions of the transverse-traceless gauge condition to Minkowski perturbation with matter presented.

关键词： gravitational wave transverse-traceless gauge condition

An Energy Management System with Mobile Energy Station Based Wireless Energy Transfer:System Design and Prototype Implementation

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China Communications 2025年第1期22卷 89-101页

作者： Yan Kang Li Jinhui Fan Xinyu Hu Jie Yu Qin Yang Kun Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

In indoor environments,various batterypowered Internet of Things(IoT)devices,such as remote controllers and electronic tags on high-level shelves,require efficient energy ***,manually monitoring remaining energy levels and battery replacement is both inadequate and *** paper introduces an energy management system for indoor IoT,which includes a mobile energy station(ES)for enabling on-demand wireless energy transfer(WET)in radio frequency(RF),some energy receivers(ERs),and a cloud *** implementing a two-stage positioning system and embedding energy receivers into traditional IoT devices,we robustly manage their energy *** experimental results demonstrate that the energy receiver can harvest a minimum power of 58 mW.

关键词： angle of arrival(AOA) Internet of Things(IoT) mobile station prototype wireless energy transfer(WET)

A fast amplitude preserving three-parameter 3D parabolic Radon transform and its application on multiple attenuation

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Petroleum Science 2025年第1期22卷 163-177页

作者： Ji-Tao Ma Kai-Ge Zhao Zhen Liao College of Geophysics China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) CNPC Key Laboratory of Geophysical Prospecting China University of Petroleum (Beijing)

Seismic wavefields propagate through three-dimensional(3D) space, and their precise characterization is crucial for understanding subsurface structures. Traditional 2D algorithms, due to their limitations, are insufficient to fully represent three-dimensional wavefields. The classic 3D Radon transform algorithm assumes that the wavefield's propagation characteristics are consistent in all directions, which often does not hold true in complex underground media. To address this issue, we present an improved 3D threeparameter Radon algorithm that considers the wavefield variation with azimuth and provides a more accurate wavefield description. However, introducing new parameters to describe the azimuthal variation also poses computational challenges. The new Radon transform operator involves five variables and cannot be simply decomposed into small matrices for efficient computation; instead, it requires large matrix multiplication and inversion operations, significantly increasing the computational load. To overcome this challenge, we have integrated the curvature and frequency parameters, simplifying all frequency operators to the same, thereby significantly improving computation efficiency. Furthermore,existing transform algorithms neglect the lateral variation of seismic amplitudes, leading to discrepancies between the estimated multiples and those in the data. To enhance the amplitude preservation of the algorithm, we employ orthogonal polynomial fitting to capture the amplitude spatial variation in 3D seismic data. Combining these improvements, we propose a fast, amplitude-preserving, 3D threeparameter Radon transform algorithm. This algorithm not only enhances computational efficiency while maintaining the original wavefield characteristics, but also improves the representation of seismic data by increasing amplitude fidelity. We validated the algorithm in multiple attenuation using both synthetic and real seismic data. The results demonstrate that the new algor

关键词： Three-parameter 3D Radon Orthogonal polynomial Amplitude-preserving Multiple attenuation

Achievable Rate Analysis and Optimization of Double-RIS Assisted Spatially Correlated MIMO with Statistical CSI

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China Communications 2025年第1期22卷 139-157页

作者： Xu Kaizhe Guo Jiajia Zhang Jun Jin Shi Ma Shaodan Department of Communications and Networking Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China State Key Laboratory of Internet of Things for Smart City University of MacaoMacao SARChina Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China State Key Laboratory of Internet of Things for Smart City and the Department of Electrical and Computer Engineering University of MacaoMacao SARChina

Reconfigurable intelligent surface(RIS)is a novel meta-material which can form a smart radio environment by dynamically altering reflection directions of the impinging electromagnetic *** the prior literature,the inter-RIS links which also contribute to the performance of the whole system are usually neglected when multiple RISs are *** this paper we investigate a general double-RIS assisted multiple-input multiple-output(MIMO)wireless communication system under spatially correlated non line-of-sight propagation channels,where the cooperation of the double RISs is also *** design objective is to maximize the achievable ergodic rate based on full statistical channel state information(CSI).Specifically,we firstly present a closedform asymptotic expression for the achievable ergodic rate by utilizing replica method from statistical *** a full statistical CSI-enabled optimal design is proposed which avoids high pilot training overhead compared to instantaneous CSI-enabled *** further reduce the signal processing overhead and lower the complexity for practical realization,a common-phase scheme is proposed to design the double *** results show that the derived asymptotic ergodic rate is quite accurate even for small-sized antenna *** the proposed optimization algorithm can achieve substantial gain at the expense of a low overhead and ***,the cooperative double-RIS assisted MIMO framework is proven to achieve superior ergodic rate performance and high communication reliability under harsh propagation environment.

关键词： common reflection pattern double RISs large system analysis MIMO replica method

A FUNCTIONAL ORLICZ BUSEMANN-PETTY CENTROID INEQUALITY FOR LOG-CONCAVE FUNCTIONS

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Acta Mathematica Scientia 2025年第1期45卷 52-71页

作者： Xiao LI Jiazu ZHOU School of Mathematical Sciences Chongqing Normal UniversityChongqing401331China School of Mathematics and Big Data Guizhou Education UniversityGuiyang550018China

In this paper,the Orlicz centroid function for log-concave functions is introduced.A rearrangement inequality of the Orlicz centroid function for log-concave functions is *** rearrangement inequality implies the Orlic... 详细信息

关键词： centroid bodies Busemann-Petty centroid inequality log-concave functions Steiner symmetrization

Performance Analysis for DAG-based Blockchain Systems Based on the Markov Process

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Journal of Systems Science and Systems Engineering 2025年第1期34卷 29-54页

作者： Xingshuo Song Shiyong Li Yanxia Chang Chi Zhang Quanlin Li School of Economics and Management Yanshan UniversityQinhuangdao066004China School of Economics and Management Bering University of TechnologyBeijing100124China

As an innovative approach, Direct Acyclic Graph (DAG)-based blockchain is designed to overcome the scalability and performance limitations of traditional blockchain systems, which rely on sequential structures. The graph-based architecture of DAG allows for faster transactions and parallel processing, making it a compelling option across various industries. To enhance the analytical understanding of DAG-based blockchains, this paper begins by introducing a Markov model tailored for a DAG-based blockchain system, specifically focusing on the Tangle structure and the interaction between tips and newly arrived transactions. We then establish a continuous-time Markov process to analyze the DAG-based blockchain, demonstrating that this process is a level-dependent quasi-birth-and-death (QBD) process. We further prove that the QBD process is both irreducible and positively recurrent. Building on this foundation, we conduct a performance analysis of the DAG-based blockchain system by deriving the stationary probability vector of the QBD process. Notably, we introduce a novel method to calculate the average sojourn time of any arriving internal tip within the system using first passage times and Phase-type (PH) distributions. Finally, numerical examples are provided to validate our theoretical findings and to illustrate the influence of system parameters on the performance metrics.

关键词： Blockchain direct acyclic graph(DAG) QBD process performance analysis sojourn time

MODIFIED BRASCAMP-LIEB INEQUALITIES AND LOG-SOBOLEV INEQUALITIES FOR ONE-DIMENSIONAL LOG-CONCAVE MEASURE

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Acta Mathematica Scientia 2025年第1期45卷 104-117页

作者： Denghui WU Jiazu ZHOU College of Science Northwest A&F UniversityYangling712100China School of Mathematics and Big Data Guizhou Education UniversityGuiyang550018China

In this paper,we develop Maurey’s and Bobkov-Ledoux’s methods to prove modified Brascamp-Lieb inequalities and log-Sobolev inequalities for one-dimensional log-concave *** prove these inequalities,the harmonic Prékopa-Leindler inequality is *** prove that these new inequalities are more efficient in estimating the variance and entropy for some functions with exponential terms.

关键词： Brunn-Minkowski inequality Prékopa-Leindler inequality Brascamp-Lieb inequality log-Sobolev inequality log-concave measure

Extended pan-spectrum fitting of energetic particle spectra

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Earth and Planetary Physics 2025年第2期9卷 366-374页

作者： WenYan Li LingHua Wang YongFu Wang XinNian Guo QianYi Ma School of Earth and Space Sciences Peking UniversityBeijing 100871China

The energy spectrum of energetic particles in space often shows a non-thermal spectral shape with two spectral transitions/breaks over a wide energy range, carrying crucial information about their acceleration, release and transportation process. To self-consistently characterize the spectral features of energetic particles, here we propose a novel extended pan-spectrum(EPS) formula to fit the particle energy-flux spectrum, which has the merit that can incorporate many commonly used spectrum functions with one spectral transition, including the pan-spectrum, double-power-law, Kappa, Ellison-Ramaty(ER) functions, etc. The formula can also determine the spectral shape with two spectral transitions, including the triple-power-law function, Kappa distribution(at low energy)plus power law(at high energy), power law(at low energy) plus ER function, etc. Considering the uncertainties in both J and E, we can fit this EPS formula well to the representative energy spectra of various particle phenomena in space, including solar energetic particles(electrons, protons, ~3He and heavier ions), anomalous cosmic rays, solar wind suprathermal particles(halo and superhalo electrons;pick-up ions and the suprathermal tail), etc. Therefore, the EPS fitting can help us self-consistently determine the spectral features of different particle phenomena, and improve our understanding of the physical nature of the origin, acceleration, and transportation of energetic particles in space.

关键词： energy spectrum fitting solar energetic particle solar wind suprathermal particle anomalous cosmic ray pick-up ion