采用激光光刀的叶片三维面形测量方法

提出一种采用激光光刀的叶片三维面形测量方法。介绍了方法原理、系统结构、信息获取与处理方案,并给出了对实际飞机发动机叶片的面形测量结果。     

Single nucleotide polymorphism data analysis - State-of-the-art review on this emerging field from a signal processing viewpoint

The basic structural units of the genome are nucleotides. A single nucleotide polymorphism (SNP) is a mutation at a single nucleotide position. This paper discusses several major problems in SNP data analysis and review some existing solutions in this work. Generally speaking, a rich set of SNP analysis problems are cast in the signal processing framework. Our objective is to offer a state-of-the art review on this topic from a signal processing viewpoint so that researchers in the signal processing field can grasp the important domain knowledge to overcome the barrier between the two fields     

Subspace-Based Blind Channel Identification for Cyclic Prefix Systems Using Few Received Blocks

In this paper, a novel generalization of subspace-based blind channel identification methods in cyclic prefix (CP) systems is proposed. For the generalization, a new system parameter called repetition index is introduced whose value is unity for previously reported special cases. By choosing a repetition index larger than unity, the number of received blocks needed for blind identification is significantly reduced compared to all previously reported methods. This feature makes the method more realistic especially in wireless environments where the channel state is usually fast-varying. Given the number of received blocks available, the minimum value of repetition index is derived. Theoretical limit allows the proposed method to perform blind identification using only three received blocks in absence of noise. In practice, the number of received blocks needed to yield a satisfactory bit-error-rate (BER) performance is usually on the order of half the block size. Simulation results not only demonstrate the capability of the algorithm to perform blind identification using fewer received blocks, but also show that in some cases system performance can be improved by choosing a repetition index larger than needed. Simulation of the proposed method over time-varying channels clearly demonstrates the improvement over previously reported methods.     

机载雷达成像中的两种改进多普勒质心估计算法

多普勒质心估计是机载脉冲多普勒雷达DBS成像技术中最为关键的步骤之一.本文针对载机惯导参数误差较大的实际情况,提出了改进的频域和时域多普勒质心估计算法.新的算法克服了传统算法受地面场景非均匀性和回波信号起伏的影响,大大提高了估计的精度.最后将这些算法用于某型脉冲多普勒雷达的实测数据,成像结果证明了算法的有效性.     

新型SiMnCr系高强度粗钢筋材料的研制

针对高强度钢筋的性能要求和钢筋生产的工艺特点 ,设计了一种新型的低碳SiMnCr系高强度钢。测定了该钢种的CCT曲线及其力学性能。在锻造或轧态下 ,可获得以低碳马氏体为主含少量贝氏体、残留奥氏体的复相组织 ,经低温回火 ,可获得高的强度 (σb>12 30MPa)和良好的塑性 (δ5≥ 8% )。     

横流均匀环境中三维线源型正负浮力射流特性研究

本文利用混合有限分析法及交错网格。对横流均匀环境中三维线源型正负浮力射流及负浮力射流的特性进行研究，分析了不同工况下流速，温度和湍动能在断面上的分布及影响射流轨迹线的因素，讨论了轨迹线上温度的变化及浮力射流的贴壁现象。对三维长线源型负浮力射流，分析了流速比，喷口弗汝德数对负浮力射流的影响。     

无线信道中的电波传播

分析了信号在无线信道中传输时所经受的两种衰落,介绍了主要的无线传播模型,在此基础上提出了对抗衰落的措施。     

双极型静电感应晶体管开关时间的测量与分析

从理论和实验两方面对静电感应晶体管（ＢＳＩＴ）的开关时间进行了分析和测量，提出了简单的分析方法，将影响ＢＳＩＴ开关时间的各个因素归结为结构因子和材料因子，从而简化了分析影响ＢＳＩＴ开关时间的因素，对于ＢＳＩＴ的实际工艺，结构设计有指导意义。     

Penalty interference of nonlinear intra-channel effects and PMD inultra high-speed TDM systems

Penalty interference of nonlinear propagation impairments and polarisation mode dispersion (PMD) caused signal distortions is experimentally investigated     

定向井井眼轨道预测方法研究及其应用

对定向井片眼轨道进行预测是实现井眼轨道定量控制的关键.本文提出了井眼轨道预测控制的力-位移模型.在此基础上,建立了描述侧向切削问题的多元幂积模式,推导了预测井斜、方位及其变化率的基本预测公式,形成了井眼轨道预测控制系统,并进一步研制了适于井场快速预测的自适应信号跟踪顶测软件,针对IBM-PC微机,开发了定向井井眼控制预测软件包DTCPS.多例预测实践表明,使用该软件包预测井眼轨道,精度较高,相符程度较好.