丝厂生丝质量模糊聚类分析

本文采用模糊聚类分析方法对五家丝厂的生丝质量进行聚类分析、结合计算机的使用，探索综合评估生丝质量的方法。     

Fuzzy压缩映象不动点定理

本文将Fuuzy压缩原理进行了推广，首次通过引入一个Fuzzy ε上半连续函数和Fuzzy链空间成功的证明了Fuzzy数值函数的不动点定理。     

模糊综合评判在机械设计中的应用

着重分析了模糊综合评判的方法以及模糊综合评判中权重和隶属度的确定，以滚动轴承为例进行了说明。     

燃气轮机气路测量参数的模糊智能选择

针对燃气轮机气路性能的监测诊断需求,基于气路小偏差分析得到的影响系数矩阵,首先从测量参数选择的相关性要求出发,应用模糊聚类分析方法得到了要求数目的目标聚类;进一步从参数选择的敏感性等要求出发,通过模糊综合评价方法从多元素聚类中筛选出了各自的代表测量参数,从而实现了燃气轮机气路测量参数的模糊智能选择.实例表明:利用模糊聚类分析方法可直接实现测量参数的相关性选择,并可以方便可靠地根据目标要求选择合理的测量参数组合,利用模糊综合评价方法的测量参数的敏感性选择更为有效可靠.     

基于模糊分数阶PI~λD~μ的柔性结构振动主动控制

为防止翅翼结构因干扰而产生振颤,以柔性悬臂梁结构为被控对象,提出一种参数自整定的分数阶比例积分微分控制器,在利用遗传算法取得优化参数后,通过模糊规则第2次对控制器参数进行在线整定,以达到实时最优控制的目的.在Simulink软件环境下进行了数值仿真,结果表明:设计的分数阶比例积分微分控制器具有记忆性,动态表征能力强.与常规比例积分微分控制器相比,冲击激励下的系统响应稳态时间缩短0.9s;简谐激励下的系统响应衰减幅度从88%提升到96%;随机激励下系统响应抖动减小,提高了稳定性.     

无刷直流电机网络伺服控制技术研究

针对直流电机网络控制的问题,考虑反馈通道和前向通道均存在延时的状况,设计了直流电机网络伺服控制器。该控制器采用基于模糊自适应调节的广义预测控制算法。模糊自适应调节方法对广义预测控制算法的输出进行调节,从而克服系统参数的不确定性对控制性能的影响。仿真实验结果表明该控制方案能够减小网络延时对系统控制特性的影响,改善系统的动态特性。     

Backstepping design of missile guidance and control based on adaptive fuzzy sliding mode control

This paper presents an integrated missile guidance and control law based on adaptive fuzzy sliding mode control. The integrated model is formulated as a block-strict-feedback nonlinear system, in which modeling errors, unmodeled nonlinearities, target maneuvers, etc. are viewed as unknown uncertainties. The adaptive nonlinear control law is designed based on backstepping and sliding mode control techniques. An adaptive fuzzy system is adopted to approximate the coupling nonlinear functions of the system, and for the uncertainties, we utilize an online-adaptive control law to estimate the unknown parameters. The stability analysis of the closed-loop system is also conducted. Simulation results show that, with the application of the adaptive fuzzy sliding mode control, small miss distances and smooth missile trajectories are achieved, and the system is robust against system uncertainties and external disturbances.     

扑翼非定常气动特性的实验研究

扑翼的动态特性使其具有与固定翼完全不同的飞行模式,为了研究扑翼在扑动周期内的非定常气动特性,建立基于虚拟仪器的扑翼风洞实验测控系统,能够实现对气动力、扑动角度、功率等物理量的实时测量;以斯特劳哈尔数作为扑翼非定常程度的度量标准,并根据斯特劳哈尔数的定义完成扑翼在不同扑动幅度、扑动频率和来流速度条件下的风洞实验;分析扑翼在不同条件下的升力、推力及推进效率,进而得出斯特劳哈尔数对扑翼气动特性的影响规律。结果表明:扑翼的气动力随斯特劳哈尔数的增大而显著增大;当斯特劳哈尔数处于特定范围内时,扑翼具有较高的推进效率。     

Study on effects of thickness on airfoil-stall at low Reynolds numbers by cusp-catastrophic model based on GA(W)-1 airfoil

The phenomena of an airfoil stall present the behaviors of catastrophe and hysteresis at low Reynolds numbers. Numerical simulation results of two-dimensional airfoil GA(W)-1 show that the width of the hysteresis loop of airfoil stall will gradually decrease and even disappear with the decrease of thickness ratio. These nonlinear characteristics are in accordance with the topological features of the cusp catastrophic model. According to the topological invariant principle, a novel topological mapping method is developed to establish the mapping relationship between cusp catastrophic model and stall characteristics of the airfoil, then the effect of thickness ratio on airfoil stall is successfully described quantitatively by cusp catastrophic model. Further, based on the established topological mapping relationship, combined with the mean flow field of the airfoil stall, potential function approach of cusp catastrophic model is first introduced to interpret the catastrophe and hysteresis of the airfoil stall, and it is found that as the thickness ratio decreases, the system's maximal potential energy gradually disappears, and the short separation bubble at the leading edge of the airfoil changes to long separation bubble, so the airfoil stall changes from a bistable system to a monostable system.     

飞机零部件更改管理方法研究

针对飞机研制过程中零部件更改管理问题,分析了国内外的管理模式,提出更为符合技术状态管理要求以及逻辑性更优的管理思路,为今后的飞机研制过程中零部件更改管理提供参考.