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China Communications 2022年第7期19卷 53-66页

作者： Chengjian Liao Kui Xu Hongpeng Zhu xiaochen xia Qiao Su Nan Sha Army Engineering University of PLA Nanjing 210007China

Aiming at the physical layer security(PLS)secure transmission existing in the information backhaul link of the satellite-UAV integrated(SUI)network,a two-layer Stackelberg game model(TSGM)that can resist full-duplex(FD)eavesdropping and jamming attacks is *** confrontation relationship between the UAV network and the attacker is established as the first layer Stackelberg *** source UAV adjusts its own transmission power strategy according to the attacker’s jamming strategy to resist malicious jamming *** internal competition and cooperation relationship in UAV network is modeled as the second layer Stackelberg game,and the optimal cooperative UAV transmits jamming signal to the attacker to resist malicious eavesdropping *** at the“selfishness”of UAV nodes,a price incentive mechanism is established to encourage UAV to actively participate in cooperation,so as to maximize the advantages of cooperative *** the proposed TSGM,we construct the utility function and analyze the closed equilibrium solution of the game model,and design a three-stage optimal response iterative(TORI)algorithm to solve the game *** simulation results show that the proposed TSGM can effectively increase the utility of the source UAV and improve the enthusiasm of cooperation compared with other power control models.

关键词： physical layer security secure transmission satellite-UAV system Stackelberg game

Robust DOA estimation and tracking for integrated sensing and communication massive MIMO OFDM systems

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Science China(Information Sciences) 2023年第10期66卷 278-296页

作者： Kui XU xiaochen xia Chunguo LI Wei XIE Jie LIU Rangang ZHU Huasen HE College of Communications Engineering Army Engineering University of PLA School of Information Science and Engineering Southeast University School of Electronic Countermeasures National University of Defense Technology School of Information Science and Technology University of Science and Technology of China

In this paper, we propose a robust direction-of-arrival(DOA) estimation and tracking scheme for a massive multiple input multiple output(MIMO) orthogonal frequency-division multiplexing(OFDM)system using integrated sensing and communication(ISAC). First, a frame structure is designed to enable integrated DOA estimation and tracking, as well as data transmission. Then, coherent combining and multipath combining methods are proposed as pilot signal preprocessing methods for robust DOA estimation and tracking. Finally, for ISAC massive MIMO-OFDM systems, a fast Fourier transform(FFT) algorithmbased robust DOA estimator design is proposed, including a preamble-based initial DOA estimation scheme and an embedded pilot-based DOA tracking scheme. The simulation results demonstrate that the proposed robust DOA estimation and tracking method can obtain accurate DOA estimation even when the signal-tonoise ratio is low. Furthermore, the estimation performance outperforms the conventional multiple signal classification(MUSIC) and estimation of signal parameters via rotational invariance technique(ESPRIT)methods.

关键词： integrated sensing and communication massive multiple input multiple output (MIMO) orthogonal frequency-division multiplexing (OFDM) direction-of-arrival (DOA) estimation and tracking frame structure and pilot sequence

Joint power control and passive beamforming optimization in RIS-assisted anti-jamming communication

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Frontiers of Information Technology & Electronic Engineering 2023年第12期24卷 1791-1802页

作者： Yang LIU Kui XU xiaochen xia Wei XIE Nan MA Jianhui XU School of Communication Engineering Army Engineering University of PLANanjing210007China

Due to the openness of the wireless propagation environment,wireless networks are highly susceptible to malicious jamming,which significantly impacts their legitimate communication *** study investigates a reconfigurable intelligent surface(RIS)assisted anti-jamming communication ***,the objective is to enhance the system’s anti-jamming performance by optimizing the transmitting power of the base station and the passive beamforming of the *** into account the dynamic and unpredictable nature of a smart jammer,the problem of joint optimization of transmitting power and RIS reflection coefficients is modeled as a Markov decision process(MDP).To tackle the complex and coupled decision problem,we propose a learning framework based on the double deep Q-network(DDQN)to improve the system achievable rate and energy *** most power-domain jamming mitigation methods that require information on the jamming power,the proposed DDQN algorithm is better able to adapt to dynamic and unknown environments without relying on the prior information about jamming ***,simulation results demonstrate that the proposed algorithm outperforms multi-armed bandit(MAB)and deep Q-network(DQN)schemes in terms of the anti-jamming performance and energy efficiency.

关键词： Reconfigurable intelligent surface(RIS) Power control Anti-jamming Reinforcement learning(RL)

Secure resource allocation against colluding eavesdropping in a user-centric cell-free massive multiple-input multiple-output system

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 500-512页

作者： Na LI Yuanyuan GAO Kui XU xiaochen xia Huazhi HU Yang LI Yueyue ZHANG College of Communication Engineering Army Engineering University of PLANanjing 210007China

We investigate the resource allocation problem of a cell-free massive multiple-input multiple-output system under the condition of colluding eavesdropping by multiple passive *** address the problem of limited pilot resources,a scheme is proposed to allocate the pilot with the minimum pollution to users based on access point selection and optimize the pilot transmission power to improve the accuracy of channel *** at the secure transmission problem under a colluding eavesdropping environment by multiple passive eavesdroppers,based on the local partial zero-forcing precoding scheme,a transmission power optimization scheme is formulated to maximize the system’s minimum security spectral *** results show that the proposed scheme can effectively reduce channel estimation error and improve system security.

关键词： Cell-free Colluding eavesdropping Limited pilot resources Access point selection Security rate

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论智媒时代有声语言创作主体意向弧思想

东北大学学报（社会科学版） 2022年第2期24卷 145-150页

作者：夏晓晨中国传媒大学播音主持艺术学院北京100024

德雷福斯的无表征智能思想给人工智能的表征主义带来巨大挑战,而作为智媒时代受人工智能冲击之一的有声语言创作,其创作过程同样可能存在无表征现象。审美空间范畴的有声语言创作作品是神经网络下的身体映射,是身体与世界的关联,这种关... 详细信息

德雷福斯的无表征智能思想给人工智能的表征主义带来巨大挑战,而作为智媒时代受人工智能冲击之一的有声语言创作,其创作过程同样可能存在无表征现象。审美空间范畴的有声语言创作作品是神经网络下的身体映射,是身体与世界的关联,这种关联即为无表征的意向弧思想,它不仅大量存在于有声语言创作的过程中,而且是有声语言创作作品的高境界追求,表现为智觉、知觉与直觉三者的辩证关系,是解决智媒时代有声语言创作作品模式化与被替代的突破口。

关键词：智媒有声语言创作意向弧无表征

维普期刊数据库博看期刊

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频分双工大规模MIMO系统时变信道估计

信号处理 2020年第3期36卷 397-406页

作者：杜福德谢威夏晓晨中国人民解放军65054部队辽宁大连116026 中国人民解放军陆军工程大学通信工程学院江苏南京210007

大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统的性能增益依赖可靠的信道估计,传统信道估计方案主要面向准静态场景,在用户高速移动场景中性能下降明显。本文研究频分双工(Frequency Division Duplex,FDD)大规模MIMO系... 详细信息

大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统的性能增益依赖可靠的信道估计,传统信道估计方案主要面向准静态场景,在用户高速移动场景中性能下降明显。本文研究频分双工(Frequency Division Duplex,FDD)大规模MIMO系统中的时变信道估计问题,利用信道向量在角度域的空时稀疏特性,提出软结构先验模型驱动的稀疏贝叶斯信道估计(Soft-Structured Prior Model based Sparse Bayesian Estimation,SSPM-SBE)方案,针对方案涉及的复杂贝叶斯估计问题,给出基于变分优化的低复杂度求解方法。SSPM-SBE方案能够充分利用当前和历史接收导频数据改善时变信道的估计性能,且无需信道大尺度信息的先验认知,仿真结果验证了方案的优越性。

关键词：大规模多输入多输出系统频分双工时变信道估计空时稀疏性

国Ⅵ GDI汽油车颗粒物排放特性与微观形貌特征

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同济大学学报（自然科学版） 2020年第2期48卷 241-248页

作者：胡志远赵心语夏孝程宋博同济大学汽车学院

试验研究了国ⅥGDI汽油车WLTC(world light vehicle test cycle)循环的颗粒物质量和固态颗粒物数量排放特性以及颗粒物微观形貌特征。结果表明,该车颗粒物质量与固态颗粒数量排放均低于国Ⅵ法规限值;固态颗粒数量累积呈3段变化形态,0~3... 详细信息

试验研究了国ⅥGDI汽油车WLTC(world light vehicle test cycle)循环的颗粒物质量和固态颗粒物数量排放特性以及颗粒物微观形貌特征。结果表明,该车颗粒物质量与固态颗粒数量排放均低于国Ⅵ法规限值;固态颗粒数量累积呈3段变化形态,0~300s、600~800s与1500~1800s的累积量显著大于其他时间段。冷机起动时颗粒数量较多,仅有0~300s的累积量已大于热机起动时颗粒物数量总累积量。颗粒物主要由基本碳粒子堆积形成,形状不规则。基本碳粒子由大量微晶碳层组成,内核无序而外壳有序;重叠时有的形成大颗粒物,有的形成大碳粒子,基本碳粒子直径、碳晶长度等特征参数呈单峰分布;与GDI(gasoline direct injection)汽油机台架试验结果比较,整车试验基本碳粒子直径、碳晶长度和曲率分布相对集中且数值相对较小。

关键词：颗粒物微观形貌缸内直喷汽油车国Ⅵ法规

Anti-oxidative effect of bicyclol on rat thoracic aorta

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Anti-oxidative effect of bicyclol on rat thoracic aorta

浙江省生理科学会2008年学术年会

作者： Keyong Liang,Wenhua Lei,xiaochen Ru and Qiang xia Department of Physiology,Zhejiang University School of Medicine,Hangzhou 310058,China

Objective:To investigate the effect of bicyclol,a novel synthetic antihepatitis drug with anti-oxidative property,on vascular tone and oxidative stress ***:Rat thoracic aortic rings were isolated for isometric tension...

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整体性原则与非物质文化遗产保护

民族艺术研究 2011年第3期24卷 5-8页

作者：王巨山夏晓晨浙江师范大学文化创意与传播学院

整体性原则是世界文化遗产保护的重要原则之一,其主张的"内容观"和"环境观"对古迹遗址等物质文化遗产的保存与修复起到了重要指导作用。在非物质文化遗产保护实践中,整体性原则也被非遗保护工作者作为"标尺"用来衡量和要求类别繁杂、形... 详细信息

整体性原则是世界文化遗产保护的重要原则之一,其主张的"内容观"和"环境观"对古迹遗址等物质文化遗产的保存与修复起到了重要指导作用。在非物质文化遗产保护实践中,整体性原则也被非遗保护工作者作为"标尺"用来衡量和要求类别繁杂、形式多样的非物质文化遗产保护,然而非物质文化遗产的存在形态、性质和保护要求大大不同于物质文化遗产。非遗保护语境下的整体性原则在保护实践中不应仅体现"内容观"和"环境观",还应在"文化生态观"、"功能观"等方面得到满足。

关键词：整体性原则非物质文化遗产保护

基于K-臂赌博机的多无人机空地网络动态资源分配方法

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电子与信息学报 2022年第9期44卷 3117-3125页

作者：马楠许魁夏晓晨谢威徐键卉申麦英陆军工程大学南京210007

针对配置大规模MIMO的多无人机空地网络中的动态资源分配问题,从最大化系统吞吐量的角度出发,该文提出一种基于K-臂赌博机的强化学习算法联合优化多个无人机的用户选择与功率分配策略。首先根据地理位置对用户进行分簇,利用簇中心节点... 详细信息

针对配置大规模MIMO的多无人机空地网络中的动态资源分配问题,从最大化系统吞吐量的角度出发,该文提出一种基于K-臂赌博机的强化学习算法联合优化多个无人机的用户选择与功率分配策略。首先根据地理位置对用户进行分簇,利用簇中心节点规划无人机飞行路径;其次在不考虑无人机之间端到端通信的情况下,将多无人机资源分配问题转化为相互独立的多个智能体强化学习问题;最后提出分幕式多智能体多状态K-臂赌博机算法来实现用户选择与功率分配的联合优化。通过将无人机每个时刻的位置索引定义为状态空间,从而使得无人机可动态适配自身位置及信道的动态变化。仿真结果表明,所提方案可根据环境状态变化自主智能调整资源分配策略,相比于已有方案能有效提升系统总吞吐量。

关键词：无人机空地网络动态资源分配多智能体强化学习 K-臂赌博机大规模MIMO