STLITE/OS20嵌入式实时操作系统原理及其应用

STLITE/OS20是用于数字电视机顶盒中的嵌入式操作系统,具有实时、多任务等特点。介绍了该操作系统的内核、存储器管理和分区、分配策略、多任务调度及任务间通过信号量和消息处理进行通信的机制、中断管理等。     

再生核质点法模拟切分轧制过程

为保证大变形弹塑性分析的稳定性,采用随材料变形的拉格朗日物质形函数分析了整个切分轧制过程。在整个变形过程中,物质核函数的影响域包含相同的节点数,通过坐标转换方法满足本质边界条件。求解了切分轧制极端变形过程,研究了不同切分楔夹角和轧件宽度对切分后轧件弯曲度的影响,数值模拟结果与实验数据吻合良好。     

An Improved Cancellation of Nonlinear Intersymbolinter ference for Voiceband Data Transmission

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一个新的软件开发增长模型─—硬核加保护带模型

本文通过瀑布模型和快速原型模型的对比，提出了一种新的软件开发模型和相应的生命周期模型，并进行了详尽的分析。本文是文章￣［２］的发展和续篇。     

Modifications to the neutral detergent cellulase digestibility method for the prediction of the metabolisable energy of compound feedstuffs containing palm kernel meal

Abstract : Practical use of the prediction equation for metabolisable energy (ME) of ruminant feeds, which resulted from a study commissioned by the UK Agriculture Industry in 1986 (MAFF 1990), has produced low predictions for feeding stuffs containing palm kernel meal. This was found to be due to the presence of galactomannans which are not readily hydrolysed by the enzymes in the cellulase preparation used in the second stage of the neutral-detergent cellulase digestibility method. An additional commercially available enzyme, Gamanase, was identified as capable of hydrolysing these compounds. Whilst Gamanase was active at the same temperature and pH range as cellulase it was found necessary to extend the incubation period from 24h to 40h to achieve adequate agreement with in-vivo digestibility. Experiments showed that the modifications to the method had no significant effect on the predicted ME for feeding-stuffs not containing palm kernel meal.     

On generalized signal-to-noise ratios in quadratic detection

The generalized signal-to-noise ratio (GSNR) is a measure of performance often used in evaluating binary hypothesis testing procedures. In this paper, we investigate the properties of the GSNR as applied to the evaluation of quadratic detectors with Gaussian hypotheses. Appealing to reproducing kernel Hilbert space theory, we give a representation for the GSNR that is particularly useful for evaluating extremal properties. Finally, we discuss an alternative performance measure that is both intuitively appealing and superior to the GSNR in some respects.This research was supported by the U.S. Office of Naval Research under Grant N00014-89-J-1321.     

An algorithm for moving target detection in IR image based on grayscale distribution and kernel function

A fast algorithm based on the grayscale distribution of infrared target and the weighted kernel function was proposed for the moving target detection（MTD） in dynamic scene of image series. This algorithm is used to deal with issues like the large computational complexity, the fluctuation of grayscale, and the noise in infrared images. Four characteristic points were selected by analyzing the grayscale distribution in infrared image, of which the series was quickly matched with an affine transformation model. The image was then divided into 32×32 squares and the gray-weighted kernel（GWK） for each square was calculated. At last, the MTD was carried out according to the variation of the four GWKs. The results indicate that the MTD can be achieved in real time using the algorithm with the fluctuations of grayscale and noise can be effectively suppressed. The detection probability is greater than 90% with the false alarm rate lower than 5% when the calculation time is less than 40 ms.     

随机删失数据下核密度估计的收敛速度

由于失访、改变治疗方案、研究时间结束时事件尚未发生等情况,所采集的数据中许多应采集而未能采集、应提交而未在一些时点上提交,造成数据不完全,这便产生了删失数据。因此研究删失数据的大样本性质是解决实际问题的关键。本文在{Xi,i≥1}是α混合的随机变量,{Yi,i≥1}是独立同分布的随机变量,且Xi与Yi相互独立的情形下,研究了随机删失数据下概率密度函数的核估计,获得了此核估计的逐点强相合速度和一致强相合速度。     

二阶非线性常微分方程的一种改进再生核方法

针对传统再生核方法求解二阶非线性微分方程只是一阶的方法,收敛速度慢的问题.通过研究再生核方法的误差估计,采用外推技巧消去了误差余项中的低阶无穷小量,给出了求解二阶非线性常微分方程初值问题的一种改进的再生核方法,在只增加少量计算的条件下使得收敛速度可以达到至少三阶.减少了原再生核方法的计算量,提高了收敛速度,数值算例表明该方法在求解非线性问题的有效性.