基于管制员工作负荷的扇区开合阀设置研究

对扇区空域实施灵活的开合管理是当前提升空域利用率的主要方法之一,利用实时的空域容量和流量信息可为扇区的开合提供预警信息,提升人力资源的利用率和紧急情况下流量波动的应对能力。基于Wick‐ens的信息处理与认知模型,构建管制员注意力资源与管制工作负荷的关系;基于仓室（SIR）模型,建立管制员注意力资源与管制工作负荷的动力...     

Variable slip window technology in transition detection on pitching airfoil

In the pitching motion, the unsteady transition and relaminarization position plays an important role in the dynamic characteristics of the airfoil. In order to facilitate the computer to automatically and accurately calculate the position of the transition and relaminarization, a Variable Slip Window Technology (VSWT) suitable for airfoil dynamic data processing was developed using the S809 airfoil experimental data in this paper and two calculation strategies, i.e., global strategy and single point strategy, were proposed: global strategy and single point strategy. The core of the VSWT is the selection of the window function h and the parameters setting in the h function. The effect of the VSWT was evaluated using the dimensionless pulse strength value (INB), which can be used to evaluate the signal characteristics, of the root mean square (RMS) value of the fluctuating pressure. It is found that: the h function characteristics have a significant influence on the VSWT. The suitable functions are H_n function constructed in this paper and step function. For the left boundary of the magnified area, the step function can obtain the largest INB value, but the robustness is not good. The H₁ function (Gaussian-like function, n = 1) can show higher robustness while ensuring a large INB value. The two computing strategies, which are single point strategy and global strategy, have their own advantages and disadvantages. The former strategy, that is the single point strategy, can achieve a higher INB value, but the RMS magnification at the feature position needs to be known in advance. Although the INB value obtained by the latter strategy, that is the global strategy, is slightly smaller than the calculation results of the former strategy, it is not necessary to know the RMS magnification at the feature position in advance. So the global strategy has better robustness. The experimental data of NACA0012 airfoil was used to further validate the developed VSWT in this paper, and the results show that the VSWT developed in this paper can still double the INB value of the transition/relaminarization position. The VSWT developed in this paper has certain practicability, which is convenient for the computer to automatically determine the transition/relaminarization characteristics.     

一种基于图形化建模的遥测参数配置工具

设计了一种基于图形化建模的适用于多星遥测参数配置的软件工具,将实际存在的物理对象作为独立的模块、使用相关图元和界面建立其逻辑模型,并可将遥测参数配置信息和图形模型绑定其中。同时根据遥测参数配置模型的特点,制定适用于遥测参数配置信息的描述规范,根据此规范对逻辑模型进行描述,最终模型以XML（可扩展标记语言）文件形式存储。该工具可在不同卫星之间复用。实践应用表明,该工具可以将配置过程非专业化和可视化,减少重复工作,降低了配置过程中的出错概率,提高配置工作的效率和质量,实现多星遥测参数配置图形化显示和配置工作的批量化。     

Modified fast Fourier transform in FBMC for satellite communications

In this paper,a Doppler scaling fast Fourier transform (Doppler-FFT) algorithm for filter bank multi-carrier (FBMC) is proposed,which can efficiently eliminate the impact of the Doppler scaling in satellite communications.By introducing a Doppler scaling factor into the butterfly structure of the fast Fourier transform (FFT) algorithm,the proposed algorithm eliminates the differences between the Doppler shifts of the received subcarriers,and maintains the same order of computational complexity compared to that of the traditional FFT.In the process of using the new method,the Doppler scaling should be estimated by calculating the orbital data in advance.Thus,the inter-symbol interference (ISI) and the inter-carrier interference (ICI) can be completely eliminated,and the signal to interference and noise ratio (SINR) will not be affected.Simulation results also show that the proposed algorithm can achieve a 0.4 dB performance gain compared to the frequency domain equalization (FDE) algorithm in satellite communications.     

基于数字图像处理的温度场测量方法的研究

通过对示温漆的颜色温度特性进行分析,给出了一种基于示温漆的彩色图像处理和温度识别方案.该方法具有成本低、精度高等优点,具有工业推广价值.     

一种用于高分辨扇扫成像的MIMO阵列

为了提高扇扫成像系统的方位分辨率,设计了一种具有高方位分辨率的多输入多输出(MIMO)阵列。首先,建立了同时适用于窄带和宽带信号的MIMO阵列与虚拟阵列之间的等效模型。在分析匹配滤波输出成分的基础上,证明了当发射信号具有良好相关特性时,MIMO阵列的匹配滤波输出可等效为单输入多输出(SIMO)阵列上经过脉冲压缩后的回波。接着,根据这一等效关系,获得了与MIMO阵列等效的虚拟阵列中虚拟发射阵元与虚拟接收阵元坐标解析解。最后,在约束阵列物理尺寸为固定值的前提下,利用该解析解设计出一种由2个发射阵元和一条接收均匀线阵列(ULA)组成的MIMO阵列。理论推导和仿真结果表明:所设计的MIMO阵列可以在恒定的物理尺寸和虚拟阵列为均匀直线阵的前提下,获得优于其他MIMO阵列和SIMO阵列的方位分辨率。     

Adaptive sliding mode control of the A-axis used for blisk manufacturing

As a key assembly in the 5-axis CNC machine tools, positioning precision of the A-axis directly affects the machining accuracy and surface quality of the parts. First of all, mechanical structure and control system of the A-axis are designed. Then, considering the influence of nonlin- ear friction, backlash, unmodeled dynamics, uncertain cutting force and other external disturbance on the control precision of the A-axis, an adaptive sliding mode control （ASMC） based on extended state observer （ESO） is proposed. ESO is employed to estimate the state variables of the unknown system and an adaptive law is adopted to compensate for the input dead-zone caused by friction, backlash and other nonlinear characteristics. Finally, stability of the closed-loop system is guaran- teed by the Lyapunov theory. Positioning experiments illustrate the perfect estimation of ESO and the stronger anti-interference and robustness of ASMC, which can improve the control precision of the A-axis by about 40 times. Processing experiments show that the ASMC can reduce the waviness, averaKe error and roughness of the nrocessed surface by 35.63%, 31.31% and 30.35%, respectively.     

基于可编程GPU的多源图像融合

针对可编程GPU模型,提出了基于CPU-GPU的并行边缘强度加权融合算法,利用CPU和GPU协同工作模式达到图像融合的目的,其中CPU负责串行任务,而GPU负责并行任务。实验结果表明,并行边缘强度加权融合算法得到的融合图像有着较好的视觉效果,信息熵和QAB/F这两个评价指标均高于文中对比算法的相应指标;从运行时间上分析,基于CPU-GPU的融合方法所需要的运行时间远低于基于CPU方法所需要的运行时间,并且图像尺寸越大,加速比越高。     

半球动压马达半球孔加工误差的分析与改进

本文分析了手工研配陀螺动压马达半球孔与轴配合间隙过程中,孔易出现的各种形状误差的原因。针对误差出现的原因,提出了选择合理的磨料配方,采取改进研具形状、材料等切实有效的方法,解决了半球孔与轴的关键研配工艺,这些方法在实际工作中被证明是有效可行的。     

任意采样率变换数字重构滤波器设计

针对理想重构函数在数字信号域不可实现而直接截取性能较差的情况,根据信号重构理论和FIR（Finite Impulse Response,有限脉冲响应）滤波器窗函数设计法,分析不同窗函数、不同截取长度对重构滤波器的影响,提出一种凯塞窗任意采样率变换数字重构滤波器设计方法.该方法通过选择合适的窗参数、截取长度、重构滤波器时域精度和量化位数,有效控制阻带最小衰减抑制数字重构镜像.设计的数字重构滤波器已成功应用于某卫星基带调制解调器,符合镜像抑制大于65 dB的性能要求.