基于改进克隆卡尔曼滤波的视觉惯性里程计实现

视觉-惯性多传感器融合方案可以有效解决GNSS据止环境下的导航问题。为了更有效地处理视觉的相对观测信息,文中研究并实现了一种基于克隆卡尔曼滤波(stochastic cloning Kalman Filter,SCKF)与滑动窗方法相结合的低成本视觉惯性里程计紧耦合算法。开源数据集实验表明,文中算法精度超过了多状态约束卡尔曼滤波(MSCKF)开源代码的效果。     

STOCHASTIC ANALYSES OF ADSORBING SOLUTE TRANSPORT IN HETEROGENEOUS UNSATURATED SOILS

ＳＴＯＣＨＡＳＴＩＣ　ＡＮＡＬＹＳＥＳ　ＯＦ　ＡＤＳＯＲＢＩＮＧ　ＳＯＬＵＴＥ　ＴＲＡＮＳＰＯＲＴ　ＩＮ　ＨＥＴＥＲＯＧＥＮＥＯＵＳ　ＵＮＳＡＴＵＲＡＴＥＤ　ＳＯＩＬＳＳＴＯＣＨＡＳＴＩＣＡＮＡＬＹＳＥＳＯＦＡＤＳＯＲＢＩＮＧＳＯＬＵＴＥＴＲＡＮＳＰ...     

一种三通道权微扰谱估计测向方法

介绍了一种三通道权微扰谱估计测向方法。该方法首先利用权微扰方法来获得阵列的协方差矩阵,进而采用特征结构类算法估计波达方向,并采用空间平滑算法来处理相干信源。仿真结果表明,该方法的估计结果更加稳健、有效。且在接收机数目较少的情况下,该方法仍具有一定的实用性。     

阵列双稳随机共振在微弱信号检测中的应用研究

阵列双稳随机共振(stochastic resonance, SR)系统可利用噪声在单个双稳SR系统基础上进一步增强微弱信号检测的能力,为强噪声背景下微弱信号的检测开创了新方法。本文应用阵列双稳SR原理进行微弱信号检测的研究,采用理论和数值仿真相结合,通过稳态自协方差函数,分析了阵列双稳SR系统输出信噪比（signal-to-noise ratio, SNR）增益。在此基础上,分别讨论了阵列噪声、外部噪声及阵列单元数对检测性能的影响。并与单个双稳SR检测弱信号进行性能比较,分析和仿真结果都表明,在相同条件下,采用阵列双稳SR比采用单个双稳SR检测微弱信号性能有较大改善。这些研究结果对于阵列双稳SR的进一步发展及应用具有重要意义。      

基于TSVD-SCN的光纤入侵信号识别算法研究

采用随机配置网络(SCN,Stochastic configurat ion network)对光纤振动信号进行识别,常由于光 纤预警系统的背景噪声问题使得网络的隐含层输出接近奇异,直接影响了SCN对光纤数据的 识别准确率。 因此本文提出了一种基于截断奇异值分解(Truncated singular value decomposition,TS VD)的SCN 方法(TSVD-SCN) 对光纤入侵信号进行识别。TSVD-SCN通过对网络的隐含层输出进行SVD分解并设置阈值去 除其中较小的 奇异值,以减少隐含层输出矩阵的条件数,提升网络识别率。本文利用占空比,平均幅差函 数,FFT求能 量占比的方法进行特征提取,采用基于TSVD-SCN算法对不同入侵振动特征矢量进行分类识 别。实验证明, 本文所提算法模型精度比SCN的模型精度更高,可以准确识别光纤入侵信号类型,对SCN网 络在实际应用中对分类精度的提高有着重要意义。     

基于智慧因子的分布式可穿戴音频人体网络随机微分博弈功率控制模型

In this study, aiming at the characteristics of randomness and dynamics in Wearable Audio-o-riented BodyNets(WA-BodyNets), stochastic differ-ential game theory is applied to the investigation of the problem of transmitted power control inconsum-er electronic devices. First, astochastic differential game model is proposed for non-cooperative decen-tralized uplink power control with a wisdom regula-tion factor over WA-BodyNets with a one-hop star topology.This model aims to minimize the cost as-sociated with the novel payoff function of a player, for which two cost functions are defined: functions of inherent power radiation and accumulated power radiation damage. Second, the feedback Nash equi-librium solution of the proposed model and the con-straint of the Quality of Service (QoS) requirement of the player based on the SIR threshold are derived by solving the Fleming-Bellman-Isaacs partial dif-ferential equations. Furthermore, the Markov prop-erty of the optimal feedback strategies in this model is verified.The simulation results show that the pro-posed game model is effective and feasible for con-trolling the transmitted power of WA-BodyNets.     

基于声表面波传感器的液体运动粘度测量方法

设计了一种用于液体运动粘度在线测量的声表面波传感器.利用液体对水平剪切模式声表面波(SHSAW)传播性质的影响,推导得出液体的密度和动力粘度与SH-SAW的传播速度变化的数学关系式,从而实现液体运动粘度的检测,设计了相应的实验设备.通过实验数据与理论数据的比较证实了该设计的可行性.     

Network selection policy in multi-radio access environment using stochastic control theory

Network selection is crucial in improving the performance of heterogeneous wireless access systems.Most of previous work on network selection or radio resource allocation concentrates on the capability of each available network and ignores the time-varying nature of wireless media due to channel fading.However,the channel condition determines the state of each wireless network and plays a vital role in ensuring quality of service in multi-radio access environment.In this article,we propose a network selection policy using stochastic control theory considering the time-varying and stochastic character of wireless channels.The proposed scheme selects one network among different alternatives in each decision epoch according to the channel state of each network,which is modeled as finite-state Markov channel,with the objectives of increasing the data-rate,decreasing the bit error rate and minishing the delay.The procedure of network selection is formulated as a stochastic control problem,which can be solved using linear programming and primal-dual index heuristic algorithm.Simulation results are presented to show that network selection has great impact on the system performance,and the proposed scheme can improve the performance significantly.     

基于隐马尔可夫模型的P2P流量控制管理系统

首先介绍P2P流量的现状,说明现在对于P2P流量要采取疏堵结合的原则。接着介绍P12P流量的管理策略和控制P2P流量的技术,并在对隐马尔可夫模型做了简单介绍之后提出一种基于隐马尔可夫模型的P2P流量控制管理系统。该系统表现出了良好的灵活性和可扩展性。     

一种近空间高超声速飞行器的制导律设计与仿真

为了实现一种由助推、近空间巡航和俯冲攻击组成的高超声速飞行器攻击弹道以对付具有大机动能力的目标,采用粒子群优化方法一体化设计高超声速飞行器的固体火箭助推器和助推弹道;巡航段水平面内采用一种3维虚拟目标比例导引律,纵向平面内基于非线性系统奇异摄动理论和虚拟目标导引方法设计一种次最优组合制导律;俯冲攻击段基于随机跳变系统理论设计一种最优制导律.3维全弹道仿真结果表明所设计的制导律合理,中制导律能够有效衔接助推段和俯冲攻击段,末制导律能够有效实现攻击大机动目标的制导任务.