GPS接收机P(Y)直捕方法研究

GPS接收机P(Y)直捕算法是基于存储的滑动相关搜索,并利用FFT将时频二维联合搜索变成时域一维搜索。同时,考虑位同步点已知的条件,接收资源池只需存储一段接收序列,缩短了捕获时间且利于硬件实现。仿真结果表明,多普勒频移为±5kHz时,所带来的峰值衰减为2dB左右,本地信号与接收信号对齐时出现明显的相关峰,很好地实现了捕获功能;提出了用重叠分段补零FFT操作实现并行相关,成倍降低了捕获时间;提出了利用位同步信息,避免了码极性翻转可能引起的信噪比损耗;针对码相位漂移,提出了优化捕获策略,可在短时间内完成重捕。     

Fast retraction of evidence in a probabilistic expert system

We present and justify a propagation algorithm to facilitate the simultaneous calculation, for every node in a probabilistic exper system of the distribution of the associated random quantity, conditional on all the evidence obtained about the remaining nodes.     

浅谈如何提高大学生英语阅读理解能力兼评《全新版大学英语快速阅读》

阅读理解能力是衡量一个人英语水平的重要因素之一,随着社会的发展和大学英语教学改革的大力推进,我们应当进一步加强对大学生阅读理解能力的培养,扩充他们对词汇量的掌握,并使他们了解相关的文化背景,从而达到提高阅读速度的目的。     

北魏道士寇谦之的新道教论析

北魏道士寇谦之是新道教的倡行者,是民间道教转化为官方道教的重要人物。寇谦之的著述及《老君音诵诫经》所反映的思想,说明寇谦之秉承早期正一道教诫,新道教以维护张陵教法为特点。寇谦之汲取儒释思想于新科之中,其改革为道教成为国家宗教奠定了基础。     

An EWMA chart for monitoring process mean

In the statistical process control literature, there exists several improved quality control charts based on cost-effective sampling schemes, including the ranked set sampling (RSS) and median RSS (MRSS). A generalized cost-effective RSS scheme has been recently introduced for efficiently estimating the population mean, namely varied L RSS (VLRSS). In this article, we propose a new exponentially weighted moving average (EWMA) control chart for monitoring the process mean using VLRSS, named the EWMA-VLRSS chart, under both perfect and imperfect rankings. The EWMA-VLRSS chart encompasses the existing EWMA charts based on RSS and MRSS (named the EWMA-RSS and EWMA-MRSS charts). We use extensive Monte Carlo simulations to compute the run length characteristics of the EWMA-VLRSS chart. The proposed chart is then compared with the existing EWMA charts. It is found that, with either perfect or imperfect rankings, the EWMA-VLRSS chart is more sensitive than the EWMA-RSS and EWMA-MRSS charts in detecting small to large shifts in the process mean. A real dataset is also used to explain the working of the EWMA-VLRSS chart.     

民营经济与赫哲族社会发展

赫哲族民营经济仍处于发展的起步阶段,破解影响民营经济发展的症结问题已经成为赫哲地区社会发展的关键所在,只有在转变发展理念、创新发展模式和提高发展质量上狠下工夫,民营经济才能实现又好又快发展。     

快速傅立叶变换在数字信号处理器上的实现研究

结合数字信号处理器的性能特点,对基2、基4、分裂基和Bruun FFT等快速傅立叶变换算法及其在TMS320C30上的实现进行了研究,开发出高效的FFT算法和程序。     

基于灰色理论的快餐店满意度综合评价

针对多层次评价体系中存在主观因素影响评估结果的客观性与精确性问题,采用灰色理论与多层次综合评价相结合的方法,对信息不完全确知的样本系统进行白化,有效解决快餐店满意度评价信息的不确定问题。并通过该评价模型应用实例分析快餐店满意度评价的实施情况。     

Generally weighted moving average control charts with fast initial response features

The generally weighted moving average (GWMA) control chart is an extension model of exponentially weighted moving average (EWMA) control chart. Recently, some approaches have been proposed to modify EWMA charts with fast initial response (FIR) features. We introduce these approaches in GWMA-type charts. Via simulation, various control schemes are designed and then their average run lengths are computed and compared. Based on the overall performance, it is showed that the DGWMA chart is the best choice especially when the shift is moderate, and the GWMA charts provided with additional FIR feature have a good performance only in detecting large shifts during the initial stage.     

多路快速以太网信号的复用传输研究

提出了一种将多路快速以太网信号复用为千兆位信号，在主干网上传输至接收端再解复用成原来信号的方法，达到了利用现有设备扩容的目的。针对 １００ＢＡＳＥ－ＴＸ信号给出了一种复用方案，并对其中关键的同步技术进行了研究。该方案已应用于硬件实现，效果良好。