联机增量关联规则算法研究

在数据挖掘应用越来越普及的今天,传统数据挖掘系统的高代价和低效已经成为其更深应用的瓶颈,联机数据挖掘系统由于其自身的集成性正引领着数据挖掘研究新的方向。但联机增量数据挖掘系统中算法也需要作相应的改进才能够适应新的需求。文章是一篇关于在联机数据挖掘系统中进行关联规则分析的文献,实现了对联机数据挖掘系统中的并行和增量关联规则分析,并根据分析过程给出了实验结论。     

一种基于数字分析的相位差测量方法

相位差的测量是电量测量的一项基本内容，有着广泛的应用。提出了一种基于数字分析的相位差测量方法，其基本思想为采用中断技术扫描被测信号的波形，然后对扫描结果进行数字分析以求得相位差。该方法有效地避免了矩形波边沿抖动问题，能够比较容易地排除干扰信号，并能够对因被测信号中含有直流分量或运算放大器零点漂移等原因引起的矩形波边沿位置偏移问题进行修正。实际应用表明，该方法的测量结果准确、稳定、可靠。     

牵引变电所继电保护测试系统设计

根据牵引变电所继电保护系统的实际情况和测试要求，提出了一种利用工控机和PLC相结合的新设计方案，实现了继电器单体和整组的自动测试功能。详细地介绍了测试系统的软硬件设计，智能逻辑转换单元的构成，以及测试功能的实现过程。     

Shear localization-martensitic transformation interactions in Fe-Cr-Ni monocrystal

A Fe-15 wt pct Cr-15 wt pct Ni alloy monocrystal was deformed dynamically (strain rate ∼10⁴ s⁻¹) by the collapse of an explosively driven thick-walled cylinder under prescribed initial temperature and strain conditions. The experiments were carried out under the following conditions: (a) alloy in austenitic state, temperature above transformation temperature; (b) alloy in transformed state; and (c) alloy at temperature slightly above M _s , propitiating concurrent shear-band propagation and martensitic transformation. The alloy exhibited profuse shear-band formation, which was a sensitive function of the deformation condition. Stress-assisted and strain-induced martensitic transformation competes with shear localization. The alloy deformed at a temperature slightly above M _s shows a significantly reduced number of shear bands. The anisotropy of plastic deformation determines the evolution of strains and distribution of shear bands. The different conditions showed significant differences that are interpreted in terms of the microstructural anisotropy. Calculated shear-band spacings based on the Grady-Kipp (GK) and Wright-Ockendon (WO) theories are compared with the observed values. The microstructure within the shear bands was characterized by transmission electron microscopy. Regions of sub-micron grain sizes exhibiting evidence of recrystallization were observed, as well as amorphous regions possibly resulting from melting and rapid resolidification. This article is based on a presentation given in the symposium “Dynamic Deformation: Constitutive Modeling, Grain Size, and Other Effects: In Honor of Prof. Ronald W. Armstrong,” March 2–6, 2003, at the 2003 TMS/ASM Annual Meeting, San Diego, California, under the auspices of the TMS/ASM Joint Mechanical Behavior of Materials Committee.     

The solidification characteristics of Fe-rich intermetallics in Al-11.5Si-0.4Mg cast alloys

After the nucleation and sedimentation of primary Fe-rich phases, the microstructures of Al-11.5Si-0.4Mg cast alloys with 0.35–1.03Fe and 0.18–0.59Mn have been studied to investigate the solidification characteristics of Fe-rich phases. Depending on the iron and manganese contents as well as cooling rates, Fe-rich phases may solidify as predendritic (primary), pre-eutectic, coeutectic, and posteutectic intermetallics at the different stages of solidification through three types of reactions: (1) predendritic (primary), (2) eutectic, and (3) peritectic reactions. It seems that Fe-rich phases may nucleate on the wetted sides of double oxide films, while the gap of the dry sides of oxide films constitutes the cracks commonly observed in the Fe-rich phases and aluminum matrix. Conventional metallurgical observations also suggest that the Fe-rich phases nucleated early during the solidification might act as nuclei for those formed subsequently, although it has not been ruled out that these phases may share the same oxide substrates. It is probable that these nucleation events may all work as suggested in the possible nucleation hierarchy for Al-11.5Si-0.4Mg cast alloys.     

对华钢材料和备件采购管理系统现状分析及可整合方面的探讨

对华钢采购系统的业务重组进行了初步的分析，对华钢材料和备件采购系统的现状及可整合方面进行了初步探讨。同时借鉴国外大公司的成功经验，提出了对材料和备件采购系统整合方面的建议。内容包括：现状分析、优缺点比较和相关建议，意欲为相关的组织者和管理者提供一些参考，使整合后的采购管理系统更趋合理。     

FrontPage2002中的文字变色效果

在FrontPage2002中,我们可以利用DHTML效果工具制作文字变色效果,但原文字必须使用黑色.如要能使文字自由变色,不妨使用一点技巧.     

用分布式防火墙构建网络屏障

本文介绍了分布式防火墙的结构,工作原理和实现策略.分析了分布式防火墙对各类问题的解决机理.最后作者指出了分布式防火墙存在的一些问题.     

分布异构环境下的数据集成和交换方法及应用

本文介绍了基于XML和Web Services的分布异构环境下的数据集成和交换方法及实现框架，详细介绍了该框架提供的服务功能及应用。最后提出了依据这一框架建设的无锡广电数据集成交换平台的解决方案，从而消除企业信息孤岛。     

8通道24位模数转换器ADS1216原理及应用

本文从内部结构、外部引脚及内部工作寄存器三个方面对8通道24位模数转换器ADS1216进行了介绍．并以海洋光学浮标光学辐照度仪为例，介绍了它的应用。最后给出了ADS1216的一些使用要点及作者的一些设计经验。