A fast and compact elimination method of empty elements from a double‐array structure

A double‐array is a well‐known data structure to implement the trie. However, the space efficiency of the double‐array degrades with the number of key deletions because the double‐array keeps empty elements produced by the key deletion. This paper presents a fast and compact elimination method of empty elements using properties of the trie nodes that have no siblings. The present elimination method is implemented by C language. From simulation results for large sets of keys, the present elimination method is about 30–330 times faster than the conventional elimination method and maintains high space efficiency. Copyright © 2003 John Wiley & Sons, Ltd.     

On Advances in Statistical Modeling of Natural Images

Statistical analysis of images reveals two interesting properties: (i) invariance of image statistics to scaling of images, and (ii) non-Gaussian behavior of image statistics, i.e. high kurtosis, heavy tails, and sharp central cusps. In this paper we review some recent results in statistical modeling of natural images that attempt to explain these patterns. Two categories of results are considered: (i) studies of probability models of images or image decompositions (such as Fourier or wavelet decompositions), and (ii) discoveries of underlying image manifolds while restricting to natural images. Applications of these models in areas such as texture analysis, image classification, compression, and denoising are also considered.     

CM-Builder: A Natural Language-Based CASE Tool for Object-Oriented Analysis

Graphical CASE (Computer Aided Software Engineering) tools provide considerable help in documenting the output of the Analysis and Design stages of software development and can assist in detecting incompleteness and inconsistency in an analysis. However, these tools do not contribute to the initial, difficult stage of the analysis process, that of identifying the object classes, attributes and relationships used to model the problem domain. This paper describes an NL-Based CASE tool called Class Model Builder (CM-Builder) which aims at supporting this aspect of the Analysis stage of software development in an Object-Oriented framework. CM-Builder uses robust Natural Language Processing techniques to analyse software requirements texts written in English and constructs, either automatically or interactively with an analyst, an initial UML Class Model representing the object classes mentioned in the text and the relationships among them. The initial model can be directly input to a graphical CASE tool for further refinement by a human analyst. CM-Builder has been quantitatively evaluated in blind trials against a collection of unseen software requirements texts and we present the results of this evaluation, together with the evaluation method. The results are very encouraging and demonstrate that tools such as CM-Builder have the potential to play an important role in the software development process.     

计算机主板电磁泄露的分析与测量

分析了计算机主板上各种信号的产生和走向，进而深入研究了计算机主板的电磁泄漏及其干扰频谱，并对计算机主板上各主要部件的电磁辐射进行了测量。     

新型无机闪烁体CeF3的时间特性研究

CeF3是新型快响应无机闪烁体．对近年国内研制的CeF3无机闪烁体的时间特性进行了研究，包括脉冲辐射诊断所关心的CeF3对快脉冲γ辐射源的时间响应．如上升时间、半高竟、脉冲后沿；同时推算并使用了用脉冲法获得晶体发光衰减常数的简单估算公式，获得的CeF3衰减常数值与国外研究同行其它测量方法得到的结果基本一致。     

电子储存环的红外边缘辐射

介绍了电子储存环中偏转磁铁入口和出口处的非均匀磁场产生的辐射——边缘辐射，给出了零边缘长度、有限边缘长度、有限直线节长度条件下的辐射通量和亮度分布，通过与常规同步辐射场的比较，充分说明了边缘辐射是一种优良的红外同步辐射光源。     

采用BETHSY自然循环实验数据对CATHARE2 V1.5qR6程序的评价

采用BETHSY自然循环实验数据对CATHARE2 V1.5qR6进行了评价.结果表明CATHRE2V1.5程序能较好地预测试验装置单相自然循环条件下的热工水力现象,对单相自然循环向两相自然循环的转变以及两相自然循环向回流冷凝运行方式的转变发生时的一回路水装量预测也比较准确,但对于两相自然循环及回流冷凝运行方式下系统的一些主要热工水力参数预测欠佳.评价结果表明,与许多国际性大型热工水力分析程序一样,CATHARE2V1.5qR6程序对剧烈两相流动的预测能力仍有待改进和完善.     

A New Grade Carbon Black Produced by Thermal Plasma Process

This paper presents a new route about producing carbon black,by wich the natural gas cracking is carried out in the absence of oxygen thanks to an electric energy supply externally given by a plasma jet.The carbon black produced by this process has a narrow size distribution and a small average diameter of 38nm as well as a highly branched aggregate.The higher DBP value of 1.40ml/g shows it should be a high structure carbon black.The FTIR spectra shows that there are lots of aromatic c-c bonds and a large amount of nitrogen-coutaining functional groups on the carbon blacks surface,such as-NH,-CN as we3ll as -CH,-OH,-COOH groups.     

节气负荷预测方法研究

针对电力负荷预测的实际困难，提出了一种进行负荷预测的新思路，即采用节气负荷作为建模数据，并根据负荷呈现出的较为明显的时序性、周期性特点，将数据分离成趋势分量、节气周期分量，以及时间噪声及白噪声，采用双因子ARIMA模型对数据进行拟合，并以BP网络方法完成负荷预测。据此，着重论述了电力负荷预测中建模数据的选择、预处理方法及其对预测精度的影响。     

目标红外辐射特性计算

文中综合考虑各种因素，计算出目标的温度场分布，并结合大气传输模型，建立目标的红外理论模型，实现红外辐射特性的计算。