On design optimization for structural crashworthiness and its state of the art

Optimization for structural crashworthiness and energy absorption has become an important topic of research attributable to its proven benefits to public safety and social economy. This paper provides a comprehensive review of the important studies on design optimization for structural crashworthiness and energy absorption. First, the design criteria used in crashworthiness and energy absorption are reviewed and the surrogate modeling to evaluate these criteria is discussed. Second, multiobjective optimization, optimization under uncertainties and topology optimization are reviewed from concepts, algorithms to applications in relation to crashworthiness. Third, the crashworthy structures are summarized, from generically novel structural configurations to industrial applications. Finally, some conclusions and recommendations are provided to enable academia and industry to become more aware of the available capabilities and recent developments in design optimization for structural crashworthiness and energy absorption.

     

Adaptive picking of microseismic event arrival using a power spectrum envelope

An automatic, adaptive, spectrogram-based algorithm for picking the arrival time of microseismic data is proposed. The algorithm provides a significant improvement in the ratio of detected events to false triggers and in the resolution of the microseismic structure. It mainly addresses the problem of automatic picking when the signal-to-noise ratio (S/N) is low and so false and missed triggers frequently occur. It combines the short time average/long time average (STA/LTA) algorithm with an envelope algorithm. It also constructs an envelope from a time-frequency representation of the signal. The threshold is set dynamically, according to the existing noise level and the S/N ratio. The algorithm also uses the fixed LTA value to represent the noise level for a seismic record. It is applied to pick the arrival times of P-waves of local events recorded at eight stations.     

基于远程桌面连接的现场设备远程控制

传统的远程控制系统,不仅造价高、维护不便,而且远程控制信号的传输距离受传输介质物理特性的限制.为此,利用Windows XP中的远程桌面连接,在A3000过程实验装置上实现了计算机远程控制,构建了新型的、经济实用的远程控制系统,使系统维护更加方便快捷.     

基于数据差异的CDP邻近时间点恢复

块级CDP系统无法提供有明确语义信息的可恢复时间点,用户难免需执行多次恢复才能获得有效数据。若对每次恢复都使用传统算法,会耗费大量时间与开销。目标时间点相邻较近的两次恢复,其有效数据间存在少量差异。将部近时间点恢复划分为4种类型,给出一种用“位表”标记差异数据块、把多余数据剔除、缺少数据写入的“差异算法”。原型实验表明,该算法能够提供正确的邻近时间点恢复,其效率优于传统算法,且差异数据量更小,效率更高。     

便于VC++进行图像编程的几个实用类

为了方便ＶｉｓｕａｌＣ＋＋的图形、图像编程,提出了几个简单而较为实用的类,并给出了其中的一些类方法的实现。     

嵌入式状态监测系统中的虚拟仪器设计

针对传统状态监测仪器的局限性,提出了嵌入式状态监测系统的虚拟仪器设计方案,并详细阐述了该方案的软硬件构架.以基于S3c2410X处理器的硬件平台为核心,扩展了信号调理和数据采集模块.采用嵌入式Linux操作系统,Qt/em-bedded图形开发工具,以基于类库的思想设计开发了虚拟仪器软面板.结果表明,采用嵌入式虚拟仪器使监测系统在精确度、可扩展性、可维护性等方面得到了显著改善.     

军用软件开发过程的质量管理体系研究

军用软件系统的开发在我军信息化建设中占据至关重要的地位。大型武器装备系统的军用软件开发,成本高、风险大、周期长,参与单位及人员众多,如何能够确保大型军用软件的质量,增强武器装备性能,成为亟待解决的课题。本文将质量管理体系引入军用软件开发过程之中,通过强化过程控制,来确保大型军用软件的开发质量,对军队信息化建设,特别是软件系统的开发起到指导和借鉴作用。     

Web日志挖掘的数据预处理研究

数据预处理在Web日志挖掘过程中起着至关重要的作用。本文详细分析了数据预处理的过程,并对用户识别提出了改进策略,最后实现了一个Web日志挖掘预处理模型(WLMPM)。     

基于双约简的GMM说话人辨识

如何能够快速准确的实现说话人识别是说话人识别研究的一个重要环节。提出双约简GMM的说话人确认方法,对语音参数进行核K-均值聚类,提取聚类中心的语音特征矢量作为训练数据,并对其进行fisher比约简,提取具有区分力强的维数。实验表明该文提取方法可以减少训练时间,并提高系统的鲁棒性。