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A New Formation Mechanism of Counterstreaming Mass Flows in Filaments and the Doppler Bullseye Pattern in Prominences

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arXiv 2025年

作者： Zhou, Chengrui Shen, Yuandeng Xia, Chun Liu, Dongxu Tang, Zehao Yao, Surui Yunnan Observatories Chinese Academy of Sciences Kunming650216 China School of Aerospace Harbin Institute of Technology Shenzhen518055 China Shenzhen Key Laboratory of Numerical Prediction for Space Storm Harbin Institute of Technology Shenzhen518055 China State Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Beijing100190 China School of Physics and Astronomy Yunnan University Kunming650500 China University of Chinese Academy of Sciences Beijing100049 China

The eruption of solar prominences can eject substantial mass and magnetic field into interplanetary space and cause geomagnetic storms. However, various questions about prominences and their eruption mechanism remain unclear. In particular, what causes the intriguing Doppler bullseye pattern in prominences has not yet been solved, despite some preliminary studies proposing that they are probably associated with counterstreaming mass flows. Previous studies are mainly based on single-angle and short timescale observations, making it difficult to determine the physical origin of Doppler bullseye patterns in prominences. Here, taking advantage of stereoscopic observations taken by the Solar Dynamics Observatory and the Solar Terrestrial Relations Observatory and a three-dimensional numerical simulation, we investigate the origin of prominence Doppler bullseye pattern by tracing a long-lived transequatorial filament/prominence from July 23 to August 4, 2012. We find that repeated coronal jets at one end of the prominence can launch the Doppler bullseye pattern. It is evidenced in our observations and simulation that during the forward traveling of jet plasma along the helical magnetic field structure of the prominence, part of the ejecting plasma can not pass through the apex of the prominence due to the insufficient kinetic energy and therefore forms a backward-moving mass flow along the same or neighboring magnetic field lines. This process finally forms counterstreaming mass flows in on-disk filaments. When the on-disk filament rotates to the solar limb to be a prominence, the counterstreaming mass flows are naturally observed as a Doppler bullseye pattern. Copyright © 2025, The Authors. All rights reserved.

关键词： Plasma magnetohydrodynamic waves

A Novel Deceptive Jamming Method Via Frequency Diverse Array

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A Novel Deceptive Jamming Method Via Frequency Diverse Array

IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)

作者： Wei Mao Hui Wang Shunsheng Zhang Xiangrong Liu National Key Laboratory of Science and Technology Test Physics and Numerical Mathematics Beijing China Research Institute of Electronic Science and Technology University of Electronic Science and Technology of China Chengdu China

Different from traditional single-element and phased-array antennas, frequency diverse array (FDA) uses a slight frequency offset across the elements to produce angle-, range- and even time-dependent transmit beampattern, which provides promising potentials to develop new jamming techniques on synthetic aperture radar (SAR) imaging. In this paper, we propose a novel deception jamming method against SAR imaging, which uses FDA to quickly generate false targets. Moreover, the position of the false target is controlled by the jammer, and the number of false targets is determined by the number of FDA elements. The proposed methods are validated by extensive simulation results with range-Doppler imaging algorithm.

关键词： Jamming Synthetic aperture radar Imaging Azimuth Interference Radar imaging

Topology Optimization of Complex Network based on NSGA-II

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Topology Optimization of Complex Network based on NSGA-II

IEEE Advanced Information technology, Electronic and Automation Control Conference (IAEAC)

作者： Zhang Bin Gan Zhi-chun Chen wen Hu Qiang-qiang Hou Jian-feng Departments of information and communication National University of Defense Technology China Science and Technology on Test Physics & Numerical Mathematic Laboratory China

This paper proposes a complex network topology optimization method based on NSGA-II with degrees and edges number unchanged. The method selects the elite parent networks by applying non-dominated layer sorting and congestion degree calculation through the network crossover and mutation operation to achieve maximum network efficiency and network invulnerability. Simulation analysis shows that the method can significantly improve the invulnerability and network efficiency of the initial networks at the same time. Optimizing the network efficiency makes the network connection show a negative correlation. The network presents a "multi-core decentralized" structure; optimizing the network invulnerability makes the connection show a positive correlation, the network presents a "close core and scattered periphery" structure; the cooperative optimization makes the network present a "tighter core and large periphery" structure, which is proved with good theoretical generality and practical application value.

关键词： Optimization Sociology Complex networks Correlation Topology

An Experimental Study on the Object Shielding Performance of Discrete Metal Wire Array

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An Experimental Study on the Object Shielding Performance of...

2018 IEEE International Conference on Computational Electromagnetics, ICCEM 2018

作者： Wang, Weidong Liu, Xin Wang, Mingliang Liu, Jiaqi Meng, Gang Gao, Zhiyong Mu, Lei Ai, Xia Zhang, Shengjun Li, Jianbing Beijing Institute of Space Long March Vehicle National Key Laboratory of Science and Technology on Test Physics Numerical Mathematical Beijing China College of Electronic Science National University of Defense Technology Changsha China

ISBN: (纸本)9781538612415

In this paper, a method of shielding the object behind a discrete metal wire array is proposed and verified by anechoic chamber experiments. Results show that if the metal wire array is dense enough (cell size is smaller than half of the wavelength), the object behind it can be effectually shielded by the discrete metal wire array. The principle can be applied to electromagnetic camouflage and protection. © 2018 IEEE.

关键词： Electromagnetic shielding

A Physical Layer key Generation method with Reliable Negotiation

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A Physical Layer Key Generation method with Reliable Negotia...

Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Yuchen Wang Xuanli Wu Zhicong Xu Wei Wu Hu Li Ran Zhang School of Electronics and Information Engineering Harbin Institude of Technology Harbin China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

There is a risk of information leakage in the process of wireless communication. The introduction of key generation in the physical layer can effectively improve the security of wireless communication. This paper proposes a new physical layer key generation method in the TDD (time division duplex) communication system. Assume that the uplink and downlink channels are reciprocal. Through LDPC (Low Density Parity Check)channel coding and negotiation algorithm, the inconsistency rate of key generation between Alice and Bob is reduced. Simulation and analysis results show that the method improves the key generation rate and reduces the key inconsistency rate.

关键词：

On networks of space-based gravitational-wave detectors

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arXiv 2023年

作者： Cai, Rong-Gen Guo, Zong-Kuan Hu, Bin Liu, Chang Lu, Youjun Ni, Wei-Tou Ruan, Wen-Hong Seto, Naoki Wang, Gang Wu, Yue-Liang CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing100190 China School of Physical Science and Technology Ningbo University Ningbo315211 China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou310024 China School of Physical Sciences University of Chinese Academy of Sciences No.19A Yuquan Road Beijing100049 China Department of Astronomy Beijing Normal University Beijing100875 China National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Beijing100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences No. 19A Yuquan Road Beijing100049 China International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences Beijing China Chinese Academy of Sciences Wuhan430071 China Department of Physics Kyoto University Kyoto606-8502 Japan Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai200030 China International Centre for Theoretical Physics Asia-Pacific Hangzhou Beijing China

The space-based laser interferometers, LISA, Taiji and TianQin, are targeting to observe milliHz gravitational waves (GWs) in the 2030s. The joint observations from multiple space-based detectors yield significant advantages. In this work, we recap the studies and investigations for the joint space-based GW detector networks to highlight: 1) the high precision of sky localization for the massive binary black hole (BBH) coalescences and the GW sirens in the cosmological implication, 2) the effectiveness to test the parity violation in the stochastic GW background observations, 3) the efficiency of subtracting galactic foreground, 4) the improvement in stellar-mass BBH observations. We inspect alternative networks by trading off massive BBH observations and stochastic GW background observation. Copyright © 2023, The Authors. All rights reserved.

关键词： Gravity waves

Algorithm for time-delay interferometry numerical simulation and sensitivity investigation

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Physical Review D 2021年第12期103卷 122006-122006页

作者： Gang Wang Wei-Tou Ni Wen-Biao Han Cong-Feng Qiao Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and Technology (APM) Chinese Academy of Sciences Wuhan 430071 China Department of Physics National Tsing Hua University Hsinchu Taiwan 30013 Republic of China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing 100049 China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCAS Hangzhou 310024 China International Centre for Theoretical Physics Asia-Pacific Beijing/Hangzhou China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Shanghai 200030 China School of Physics University of Chinese Academy of Sciences Beijing 100049 China CAS Center for Excellence in Particle Physics Beijing 100049 China

We introduce a generic algorithm to determine the time delays and spacecraft positions to compose any time-delay interferometry (TDI) channel in the dynamical case and evaluate its sensitivity by using a full numerical method. We select 11 second-generation TDI channels constructed from four approaches and investigate their gravitational wave responses, noise levels, and averaged sensitivities under a numerical LISA orbit. The sensitivities of selected channels are various especially for frequencies lower than 20 mHz. The optimal channel A2 (or equivalently E2) combined from second-generation Michelson TDI channels (X1, X2, and X3) achieves the best sensitivity among the channels, while the Sagnac α1 channel shows the worst sensitivity. Multiple channels show better sensitivities at some characteristic frequencies compared to the fiducial X1 channel. The joint A2+E2+T2 observation not only enhances the sensitivity of the X1 channel by a factor of 2 to 2, but also improves the capacity of sky coverage.

关键词： Gravitational waves Gravitational wave detectors

Integrating Neural Networks and Tensor Networks for Computing Free Energy

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arXiv 2025年

作者： Cao, Hanyan Wang, Yijia Pan, Feng Zhang, Pan CAS Key Laboratory for Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing100049 China Centre for Quantum Technologies National University of Singapore 117543 Singapore Science Mathematics and Technology Cluster Singapore University of Technology and Design 8 Somapah Road 487372 Singapore School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced Study UCAS Hangzhou310024 China International Centre for Theoretical Physics Asia-Pacific Hangzhou Beijing China

Computing free energy is a fundamental problem in statistical physics. Recently, two distinct methods have been developed and have demonstrated remarkable success: the tensor-network-based contraction method and the neural-network-based variational method. Tensor networks are accurate, but their application is often limited to low-dimensional systems due to the high computational complexity in high-dimensional systems. The neural network method applies to systems with general topology. However, as a variational method, it is not as accurate as tensor networks. In this work, we propose an integrated approach, tensor-network-based variational autoregressive networks (TNVAN), that leverages the strengths of both tensor networks and neural networks: combining the variational autoregressive neural network’s ability to compute an upper bound on free energy and perform unbiased sampling from the variational distribution with the tensor network’s power to accurately compute the partition function for small sub-systems, resulting in a robust method for precisely estimating free energy. To evaluate the proposed approach, we conducted numerical experiments on spin glass systems with various topologies, including two-dimensional lattices, fully connected graphs, and random graphs. Our numerical results demonstrate the superior accuracy of our method compared to existing approaches. In particular, it effectively handles systems with long-range interactions and leverages GPU efficiency without requiring singular value decomposition, indicating great potential in tackling statistical mechanics problems and simulating high-dimensional complex systems through both tensor networks and neural networks. © 2025, CC BY.

关键词： Statistical mechanics

Device-Independent-quantum-randomness-enhanced zero-knowledge proof

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arXiv 2021年

作者： Li, Cheng-Long Zhang, Kai-Yi Zhang, Xingjian Yang, Kui-Xing Han, Yu Cheng, Su-Yi Cui, Hongrui Liu, Wen-Zhao Li, Ming-Han Liu, Yang Bai, Bing Dong, Hai-Hao Zhang, Jun Ma, Xiongfeng Yu, Yu Fan, Jingyun Zhang, Qiang Pan, Jian-Wei Hefei National Laboratory for Physical Sciences at Microscale Department of Modern Physics University of Science and Technology of China Hefei230026 China Shanghai Branch CAS Center for Excellence Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Shanghai201315 China Shanghai Research Center for Quantum Sciences Shanghai201315 China Shanghai Jiao Tong University Shanghai200240 China Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Beijing100084 China Shenzhen Institute for Quantum Science and Engineering Department of Physics Southern University of Science and Technology Shenzhen518055 China State Key Laboratory of Mathematical Engineering and Advanced Computing Henan Zhengzhou450001 China Jinan Institute of Quantum Technology Jinan250101 China

Zero-knowledge proof (ZKP) is a fundamental cryptographic primitive that allows a prover to convince a verifier of the validity of a statement without leaking any further information[1]. As an efficient variant of ZKP, non-interactive zero-knowledge proof (NIZKP) adopting the Fiat-Shamir heuristic is essential to a wide spectrum of applications, such as federated learning[2], blockchain and social networks[3]. However, the heuristic is typically built upon the random oracle model making ideal assumptions about hash functions, which does not hold in reality and thus undermines the security of the protocol[4]. Here, we present a quantum resolution to the problem. Instead of resorting to a random oracle model, we implement a quantum randomness service. This service generates random numbers certified by the loophole-free Bell test[5, 6] and delivers them with post-quantum cryptography (PQC) authentication[7]. Employing this service, we conceive and implement a NIZKP of the three-colouring problem[8]. By bridging together three prominent research themes, quantum non-locality, PQC and ZKP, we anticipate this work to open a new paradigm of quantum information science. Copyright © 2021, The Authors. All rights reserved.

关键词： Hash functions