Software defect prevention based on human error theories

Software defect prevention is an important way to reduce the defect introduction rate.As the primary cause of software defects,human error can be the key to understanding and preventing software defects.This paper proposes a defect prevention approach based on human error mechanisms:DPeHE.The approach includes both knowledge and regulation training in human error prevention.Knowledge training provides programmers with explicit knowledge on why programmers commit errors,what kinds of errors tend to be committed under different circumstances,and how these errors can be prevented.Regulation training further helps programmers to promote the awareness and ability to prevent human errors through practice.The practice is facilitated by a problem solving checklist and a root cause identification checklist.This paper provides a systematic framework that integrates knowledge across disciplines,e.g.,cognitive science,software psychology and software engineering to defend against human errors in software development.Furthermore,we applied this approach in an international company at CMM Level 5 and a software development institution at CMM Level 1 in the Chinese Aviation Industry.The application cases show that the approach is feasible and effective in promoting developers' ability to prevent software defects,inde pendent of process maturity levels.     

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.     

最佳平方逼近的异步时钟恢复插值滤波器设计

给出了一种异步时钟恢复的最佳平方逼近插值滤波器设计，该滤波器基于最小平方逼近理论，采用易于硬件实现的Farrow结构；克服了拉格朗日插值滤波器参数固定而窗函数截短插值滤波器结构复杂的问题。对我国航天测控设备的数字化和小型化具有较好的应用价值。     

FrFT-CSWSF:Estimating cross-range velocities of ground moving targets using multistatic synthetic aperture radar

Estimating cross-range velocity is a challenging task for space-borne synthetic aperture radar（SAR）, which is important for ground moving target indication（GMTI）. Because the velocity of a target is very small compared with that of the satellite, it is difficult to correctly estimate it using a conventional monostatic platform algorithm. To overcome this problem, a novel method employing multistatic SAR is presented in this letter. The proposed hybrid method, which is based on an extended space-time model（ESTIM） of the azimuth signal, has two steps： first, a set of finite impulse response（FIR） filter banks based on a fractional Fourier transform（FrFT） is used to separate multiple targets within a range gate; second, a cross-correlation spectrum weighted subspace fitting（CSWSF） algorithm is applied to each of the separated signals in order to estimate their respective parameters. As verified through computer simulation with the constellations of Cartwheel, Pendulum and Helix, this proposed time-frequency-subspace method effectively improves the estimation precision of the cross-range velocities of multiple targets.     

基于情感过滤学说的大学英语教学策略研究

情感是人脑的一种机能，是对客观事物抱有不同好恶而产生的内心变化和外部表现。受传统教育观念的影响，认知技能的发展长期以来一直都在外语教学中占主导地位。基于克拉中的情感过滤学说，从其对外语教学的启示进行阐释，就如何优化大学英语教学提出一些教学方法和策略。     

自调节模拟低通滤波器的研究

通过对有源低通滤波器，频率／电压转换器AD650及其变容二极管的特性分析，提出由信号频率来自调节有源低通滤波器截止频率的新设计方案，并对其可行性进行了分析和研究。     

地磁测量数据野值的辨识与剔除

针对地磁测量野值的辨识与剔除方法进行了深入研究。分析了野值辨识与剔除的基本原理,基于孤立型野值和斑点型野值模型分析比较了不同的野值剔除方法。利用地磁场实测信息,优化了野值剔除方法的参数,并从不同角度验证了方法的野值修复效果。仿真结果表明,在观测信息为总强度地磁信息条件下,优化的最小二乘B样条逼近法能够有效地辨识野值,具有较好的野值修复效果。     

一种基于组合导航系统的新融合滤波算法

本文设计了一种可用于地面用户的低成本组合导航系统，提出了基于该系统的新信息融合方法，即模糊卡尔曼滤波算法和地图匹配技术联合起来。仿真结果表明模糊卡尔曼滤波算法相当于一数据平滑处理窗口，具有比常规卡尔曼滤波算法更高的精度。     

推进剂利用系统连续液位测量滤波算法研究

针对我国低温推进剂利用系统中连续液位测量中的错节问题,提出了一种基于流量的液位测量滤波算法。介绍了该算法的基本原理,对算法进行了数学建模与数字仿真。通过对仿真结果的分析证实了该算法可以有效解决火箭飞行过程中由于液位晃动造成的测量误差问题,具有一定的工程应用价值。     

基于平滑滤波与最小二乘支持向量机的指纹图像识别研究

平滑滤波能抑制或消除噪声,获得高质量的图像。建立了完整的指纹识别系统,通过预处理、特征提取和分类识别3个过程,实现了指纹的分类识别;研究了预处理过程中的滤波增强方法,比较了邻域平均、高斯平滑和中值滤波的处理效果;在识别阶段采用最小二乘支持向量机,进行指纹识别实验,并对实验结果进行了比较。