毫秒脉冲星计时的多星观测

在评价脉冲星时研究发展趋势的基础上 ,讨论了基于毫秒脉冲星自转的脉冲星时间的短期特征和长期稳定度。并对影响其稳定度的因素作了初步分析。 5 0m射电望远镜计时观测的目的之一就是综合脉冲星时研究。对于 5 0m望远镜计时观测的选星和由多星观测进行综合脉冲星时研究中的数据分析问题进行了讨论。     

The asymmetry of the solar cycle: A result of non-linearity

The paper presents a numerical analysis of Wolf sunspot numbers, with emphasis being laid on the asymmetry of the cyclic variation. To that purpose we have used the standard tables of monthly numbers and, in addition to the Fourier transform, we have done an overall analysis of the trend around each maximum. Many of these maxima present an asymmetry, and sometimes the presence of two maxima is evident. The non-linear RLC van der Pol model suggested by Polygiannakis and Moussas [Polygiannakis, J.M., Moussas, X. A nonlinear RLC solar cycle model. Solar Physics 163, 193–203, 1996] can explain many features of the observed asymmetries. Our analysis shows that a consistent deconvolution in two Gaussian curves is possible for each maximum. We may presume that the observed sunspot time series includes a hidden complex structure. This could give some hints of a behavior typical for coupled non-linear oscillators. It is a matter of further interpretations. whether such “oscillators” are just a simple approximation of a much complex phenomenon, or are a sign of another more physically based model like the dynamo model (or other models).     

用人工智能搜索策略进行抗疲劳优化设计

 将人工智能搜索策略应用于抗疲劳优化设计中,针对工程实际中大量存在的离散变量的优化问题,提出了一套不同于传统数学规划法的方法,从根本上解决了处理离散变量的困难。还以多钉多层板接头为算例,作了优化计算,说明本文提出的方法可行,计算程序适用。并且优化结果比数学规划法好。     

俄制引进装备中数字板件国产化研制替代的探讨

针对维修中俄制引进地空导弹武器系统国产化数字板件替代装备联调过程中出现的延时累计误差“瓶颈”问题，分析研究了具体解决办法和措施，并通过了武器系统实弹打靶检验。     

面向下行多天线传输的能效最优上行训练

针对时分双工(TDD,Time Division Duplex)多天线系统的下行传输,研究了以能量效率(EE,Energy Efficiency)最大为准则的上行训练设计问题.证明了存在信道估计误差时系统EE和频谱效率(SE,Spectrum Efficiency)上界是上行训练长度的凹函数,分析了信噪比和电路功耗等因素对两种准则下最优训练长度的影响.分析和仿真结果表明,当信噪比很高时,基于EE最优的设计将退化成基于SE最优的设计；而一般情况下,与最大化SE的训练设计相比,最大化EE要求系统配置更长的训练.     

起始年龄与二语语言能力相关性研究

近年来,中国的外语学习出现了低龄化的趋势,各种双语早教班和幼儿园的出现似乎在提醒人们,外语学习越早越好。语言习得关键期假说也成为二语习得领域的研究重点之一,语言学者们在外语学习的起始年龄对外语学习效率的影响力方面无法达成共识。在对比分析关键期相关研究的基础上,通过实证研究试图证明不同年龄开始接触英语的学习者在语言能力方面并没有显示出明显的差异,关键期假说不适用于主要基于学校教学的外语教学。     

混合回归模型及其在高耸结构风响应时域分析中的应用

针对多维ＡＲ模型同时求解回归系数矩阵所有元素的一些不足之处，本文提出了混合回归模型。通过对某一高耸结构的分析，表明混合回归模型对脉动风的模拟是有效的，并人数值模拟角度验证了，对于线性结构，外激的各态历经性可保证响应的各态历经性。     

Real-time trajectory planning for UCAV air-to-surface attack using inverse dynamics optimization method and receding horizon control

This paper presents a computationally efficient real-time trajectory planning framework for typical unmanned combat aerial vehicle (UCAV) performing autonomous air-to-surface (A/S) attack. It combines the benefits of inverse dynamics optimization method and receding horizon optimal control technique. Firstly, the ground attack trajectory planning problem is mathematically formulated as a receding horizon optimal control problem (RHC-OCP). In particular, an approximate elliptic launch acceptable region (LAR) model is proposed to model the critical weapon delivery constraints. Secondly, a planning algorithm based on inverse dynamics optimization, which has high computational efficiency and good convergence properties, is developed to solve the RHCOCP in real-time. Thirdly, in order to improve robustness and adaptivity in a dynamic and uncer- tain environment, a two-degree-of-freedom (2-DOF) receding horizon control architecture is introduced and a regular real-time update strategy is proposed as well, and the real-time feedback can be achieved and the not-converged situations can be handled. Finally, numerical simulations demon- strate the efficiency of this framework, and the results also show that the presented technique is well suited for real-time implementation in dynamic and uncertain environment.     

基于动态时间阈值的报警聚合方法研究

针对网络入侵检测中持续性攻击引发的多个报警事件时间间隔变化的问题,引入时间间隔变异系数描述报警的时间波动特征;通过将报警数据属性分为时间约束属性和相似度约束属性,提出了一种利用动态时间阈值约束的相似报警数据聚合方法。实验结果表明,这种方法能有效减少持续性攻击触发的冗余报警。     

INTERNET网检工具逻辑算符及检索表达式优化

对ＩＮＴＥＲＮＥＴ网检工具逻辑算符进行分析和比较。在此基础上，提出制定和优化检索表达式的方法。