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Effects Evaluation on Sweep Jamming

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Effects Evaluation on Sweep Jamming

2011 IEEE International Conference on information Theory and information Security(ICITIS 2011)

作者： Ying Zhu 1) 2) Qina Gao 1) 2) Zhanbin Jiang 2) 1) school of Electronics and information engineering Beihang university beijing china 2) beijing Aeronautical Technology Research Center beijing china

One method of effects evaluation on sweep jamming to conical-scan radar is discussed. Based on the analysis of operations performance of aircraft and weapons system, the relation between the ratio of input jamming power of radar which was oppressed in the minimal shot distance to the radar angle tracking error and the formula of shot error were obtained. The kill probability model was set up. In the end, using the model, the kill probability for an application example was computed, and the jamming effect was evaluated in terms of the results.

关键词： sweep jamming effects evaluation shot error kill probability

基于分层空时结构的多码CDMA系统中一种新的迭代均衡接收算法的研究

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通信学报 2005年第1期26卷 48-53页

作者：赵军辉李秀萍王东明尤肖虎澳门科技大学资讯科技学院北京邮电大学电信工程学院北京100876 东南大学移动通信国家重点实验室江苏南京210018

为了提高基于垂直结构的分层空时结构(V-BlAST, vertical bell-laboratories layered space-time)的多码 CDMA 系统的抗干扰能力与系统容量,文章提出了一种将 MMSE 均衡与 Turbo 译码联合运算进行的方法,得到了一种针对该系统的迭代均... 详细信息

为了提高基于垂直结构的分层空时结构(V-BlAST, vertical bell-laboratories layered space-time)的多码 CDMA 系统的抗干扰能力与系统容量,文章提出了一种将 MMSE 均衡与 Turbo 译码联合运算进行的方法,得到了一种针对该系统的迭代均衡接收算法。该接收算法包含两个连续的软输入软输出模块,首先经过 MMSE 均衡后得到第一个软输出,然后从 Turbo 译码器得到第二个软输出。每一次迭代过程中,从均衡和译码中得到的外赋信息作为第二次迭代的先验信息。仿真结果表明,文章提出的迭代均衡接收算法相比较传统非迭代接收算法,性能有非常可观的改善。

关键词：多码码分多址垂直结构的分层空时结构迭代均衡软输入软输出

Attitude Dynamics Modeling of a Small-Scale Unmanned Helicopter

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Attitude Dynamics Modeling of a Small-Scale Unmanned Helicop...

2012 IEEE International Conference on Intelligent Control,Automatic Detection and High-End Equipment（ICADE 2012）

作者： Yue Pan,Ping Song,Kejie li,yun Wang and Xiaoyue Wang Intelligent Robotics Institute,school of Mechatronical engineering beijing Institute of Technology 100081,beijing,china

The attitude dynamics model is the basis for attitude control and the attitude model is very complex because the small- scale unmanned helicopter is a multivariable,nonlinear,time- varying,strong-coupling *** reduce the complexity of the attitude model,a simplified attitude dynamics model for small- scale unmanned helicopter in hover or low speed forward flight was ***,the linear model with unknown parameters was determined by first-principle approach and small perturbation ***,the PEM system identification approach was used to identify the parameters of the *** validity of the attitude model was verified using experimental data obtained in real *** validation results showed the effectiveness and high accuracy of the modeling *** attitude modeling method combines the advantages of first-principle method and system identification *** model has simple structure,it is easy to implement and can be conveniently applied in other unmanned aerial vehicles.

关键词： Attitude model First-principle Parameter estimation Small-scale unmanned helicopter

A Clonal Chaos Adjustment Algorithm for Multi-modal Function Optimization

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A Clonal Chaos Adjustment Algorithm for Multi-modal Function...

第二十七届中国控制会议

作者： Hong lu1,Mu Zhichun 2 1.Department of Electronic engineering,Huaihai Institute of Technology,lianyungang 222005,P.R.china 2.school of information engineering,university of Science and Technology beijing,beijing 10083,P.R.china

By integrating chaos mechanism and niche technique,a novel immune algorithm--the Clonal Chaos Adjustment Algorithm（CCAA） is proposed based on the clonal selection principle and idiotypic immune network theory exhibited in bio-logical immune *** advantages of the ergodic and stochastic properties of chaotic variable,an adaptive chaos mu-tation operator is designed by the combination of prior knowledge of antibody and evolution *** operator can avoid blind search effectively and enhance the convergence *** using stochastic processes martingale theory,the martingale characteristic of the average fitness of the population is analyzed and the almost sure strong convergence of CCAA is deduced. Furthermore,it is proved that the algorithm is globally convergent with probability 1 in a finite number of steps when the state space is *** simulation results of multi-modal function optimization show that CCAA can inhibit prematurity and has preferable global convergence performance.

关键词： Clonal selection principle Chaos Martingale Almost sure strong convergence

基于异步分层联邦学习的数据异质性处理方法研究

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计算机工程与科学 2024年第7期46卷 1237-1244页

作者：郭昌昊唐湘云翁彧中央民族大学信息工程学院北京100081

在物联网设备遍布的时代,时刻都在产生大量数据,数据分布和数据量各不相同,因此数据异质性普遍存在。针对物联网环境中智能设备的联邦学习挑战,传统联邦学习的同步机制解决数据异质性(NON-IID)问题并不理想,且面临着单点故障和维护全局... 详细信息

在物联网设备遍布的时代,时刻都在产生大量数据,数据分布和数据量各不相同,因此数据异质性普遍存在。针对物联网环境中智能设备的联邦学习挑战,传统联邦学习的同步机制解决数据异质性(NON-IID)问题并不理想,且面临着单点故障和维护全局时钟的复杂性问题,而异步机制则可能带来额外的通信开销和NON-IID数据分布导致的过时性问题。分层联邦学习结合异步机制在应对数据异质性的问题时更加灵活,为此,提出了一种基于分层联邦学习的异步分层联邦学习方法。首先,使用BIRCH算法分析物联网中各节点的数据分布并进行簇的划分;然后,对簇中的数据进行拆分与验证,目的是找到数据质量高的节点,然后将数据质量高的簇中的节点打散,重组到其他数据质量低的簇中,形成新的簇;最后,进行簇内聚合和全局聚合的两阶段模型训练。此外,基于MNIST数据集,对提出的方法进行了评估。结果表明,与经典方法相比,所提方法在NON-IID数据集上收敛速度提高,而且在模型精度上提高了15%以上。

关键词：物联网联邦学习异步联邦学习分层联邦学习数据异质性数据分布

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基于PSTN的远程图像监视系统的软件实现

系统仿真学报 2001年第S2期13卷 519-521页

作者：潘立军王汇源付永生吕尧新山东大学信息科学与工程学院济南250061 北京邮电大学继续教育学院北京100876

提出并实现了一种基于PSTN的远程图像监视系统。该系统的主要功能模块均是在Windows操作系统下的Visual C++6.0编程环境中开发的,用以实现通过图像采集卡采集外部的视频信息,然后对其进行编码压缩,将压缩后的码流发送到和本地计算机建... 详细信息

提出并实现了一种基于PSTN的远程图像监视系统。该系统的主要功能模块均是在Windows操作系统下的Visual C++6.0编程环境中开发的,用以实现通过图像采集卡采集外部的视频信息,然后对其进行编码压缩,将压缩后的码流发送到和本地计算机建立拨号连接的任意一台远程计算机;远程计算机则对接收到的码流进行实时解码显示和存储。

关键词：图像编码远程监控视频传输

ADAPTIVE COPY AND DATA DISSEMINATION IN VEHICUlAR AD-HOC NETWORKS

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ADAPTIVE COPY AND DATA DISSEMINATION IN VEHICULAR AD-HOC NET...

2009 IEEE International Conference on communication Technology and Applications（ICCTA2009）

作者： Jianwei Niu~1 Chang liu~1 Canfeng Chen~2 Jian Ma~2 1school of Computer Science and engineering Beihang university beijing 100191 china 2 Nokia Research Center beijing 100176 china

＜正＞Vehicular ad-hoc networks（VANETs） are promising for more and more intelligent transportation applications,where information is disseminated over a group of *** are characterized for its unstable framework,in which the isolated vehicles communicate with others only when the unexpected meetings occur. As a result,some available data dissemination schemes do not work well in VANETs. In this paper,we propose an opportunistic auto-adaptive dissemination scheme-Adaptive Copy and Spread（ACS） Algorithm - for VANETs,which makes use of the moving patterns of vehicles like direction and velocity,and dynamically adjusts the dissemination *** scheme dynamically increases or decreases the number of message copies inside the broadcast area,and vehicles can intelligently decide when to start or stop broadcast a *** is designed to keep the message at the effective area’s boundary to inform the entering vehicles as soon as *** simulation results show that ACS enhance the data dissemination performance significantly with a smaller network load compared with random choice algorithm and Epidemic dissemination algorithm over a series of scenarios.

关键词： Adaptive Copy and Spread Vehicular Ad hoc Networks Opportunistic Networks Data Dissemination

JOINT SUBCARRIER POWER AllOCATION AND EQUAl BER POWER CONTROl FOR UPlINK MC-CDMA SYSTEMS

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JOINT SUBCARRIER POWER ALLOCATION AND EQUAL BER POWER CONTRO...

2009 IEEE International Conference on communication Technology and Applications（ICCTA2009）

作者： Yizhi Feng Yaorong lin Hongjiang Wang school of Electronic and information engineering South china university of Technology Guangzhou

＜正＞In this paper,we consider joint subcarrier power allocation and equal bit-error-rate（BER） power control（PC） for the uplink multicarrier code division multiple access（MC-CDMA） systems with MMSE successive interference cancellation （MMSE-SIC）.We first propose a novel subcarrier power adaptive allocation scheme which maintains the constant BER single user bound（SUB） and then combine it with equal BER PC for the uplink MC-CDMA systems with *** joint scheme is compared with equal BER PC without subcarrier power adaptation for the uplink MC-CDMA systems with *** results show that the joint scheme can achieve a much lower BER SUB and a much better BER performance.

关键词： MC-CDMA subcarrier power adaptation Equal BER power control MMSE successive interference cancellation(SIC)

A Post-Quantum Cross-Domain Authentication Scheme Based on Multi-Chain Architecture

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Computers, Materials & Continua 2024年第2期78卷 2813-2827页

作者： Yi-Bo Cao Xiu-Bo Chen yun-Feng He lu-Xi liu Yin-Mei Che Xiao Wang Ke Xiao Gang Xu Si-Yi Chen information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China information Center of china North Industries Group Corporation Beijing100089China school of information Science and Technology North China University of TechnologyBeijing100144China

Due to the rapid advancements in network technology,blockchain is being employed for distributed data *** the Internet of Things(IoT)scenario,different participants manage multiple blockchains located in different trust domains,which has resulted in the extensive development of cross-domain authentication ***,the emergence of many attackers equipped with quantum computers has the potential to launch quantum computing attacks against cross-domain authentication schemes based on traditional cryptography,posing a significant security *** response to the aforementioned challenges,our paper demonstrates a post-quantum cross-domain identity authentication scheme to negotiate the session key used in the cross-chain asset exchange ***,our paper designs the hiding and recovery process of user identity index based on lattice cryptography and introduces the identity-based signature from lattice to construct a post-quantum cross-domain authentication ***,our paper utilizes the hashed time-locked contract to achieves the cross-chain asset exchange of blockchain nodes in different trust ***,the security analysis reduces the security of the identity index and signature to learning With Errors(lWE)and Short Integer Solution(SIS)assumption,respectively,indicating that our scheme has post-quantum *** but not least,through comparison analysis,we display that our scheme is efficient compared with the cross-domain authentication scheme based on traditional cryptography.

关键词： Cross-domain identity authentication lattice-based cryptography blockchain hashed time-locked contract