8098单片机在乳化沥青生产中的应用

介绍了乳化沥青的生产工艺及过程，较详细讨论了８０９８单片机在乳化沥青生产中测控系统的硬件设计和软件设计的方法及特点。     

软件可靠性概要

本文概述作者对软件可靠性的若干总体看法,具体技术问题不作深入讨论,甚至许多问题仅仅提及而不加展开,数以千计的有关文献也不加列举。本文试图阐述软件可靠性理论研究和工程实践的基本范畴,内容包括软件可靠性与软件工程的关系、软件可靠性的含义、软件可靠性的基本问题、国内外软件可靠性研究现状、当前软件可靠性面临的主要问题,以及当前我国软件可靠性领域应开展的工作。     

关于工控机对电机功率测量的软件处理方法

在工控机对电机功率测试时会遇到相住处理的问题，有两种解决的途径，或者用硬件方法，或者用软件方法，本文介绍了一种软件的处理方法，实验证明该方法是可行的。     

一种基于虚拟对象的进程检查点实现方法

检查点回卷恢复策略是实现软件容错的一种重要方法。基于虚拟对象策略的进程检查点实现方法把应用层与系统层的直接交互被重定向为应用层与虚拟对象层的交互以及虚拟对象层与系统层的交互。故障恢复时,虚拟对象层重新和系统层捆绑结合,使得进程环境故障前后的差异性对应用层透明。另外,基于虚拟对象的检查点策略不须要进行对象句柄转换,避免了对象句柄转换所带来的开销。该方法具有开销小的特点,并且支持多线程及线程间的同步。     

回溯自动机的两个基本定理

本文详细证明了回溯自动机的两个基本定理,得到下列结论:1)ω∈~*,ω∈L(M)iffω=R(G);2)从G中q处删除一个CSg(结点q保留)或者添加一个CSq(q不需添加)后的图G′也是M的接受状态活动图。     

MGB probe assay for rapid detection of mtDNAl1778 mutation in the Chinese LHON patients by real-time PCR

Objective： Leber＇s hereditary optic neuropathy （LHON） is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA （mtDNA）. Many unsolved questions regarding the penetrance and pathophysiological mechanism of LHON demand efficient and reliable mutation testing. This study aims to develop a minor groove binder （MGB） probe assay for rapid detection of mtDNA11778 mutation and heteroplasmy in Chinese LHON patients by real-time polymerase chain reaction （PCR）. Methods： Forty-eight patients suspected of having LHON and their maternal relatives underwent a molecular genetic evaluation, with 20 normal individuals as a control group at the same time. A real-time PCR involving two MGB probes was used to detect the mtDNA 1 1778 mutation and heteroplasmy. A linear standard curve was obtained by pUCmLHONG and pUCmLHONA clones. Results： All 48 LHON patients and their maternal relatives were positive for rntDNA11778 mutation in our assay, 27 heteroplasmic and 21 homoplasmic. Eighteen cases did not show an occurrence of the disease, while 9 developed the disease among the 27 heteroplasmic mutation cases. Eleven did not show an occurrence of the disease, while 10 cases developed the disease among 21 homoplasmic mutation cases. There was a significant difference in the incidence between the heteroplasmic and the homoplasmic mutation types. The time needed for running a real-time PCR assay was only 80 min. Conclusion： This real-time PCR assay is a rapid, reliable method for mtDNA mutation detection as well as heteroplasmy quantification. Detecting this ratio is very important for predicting phenotypic expression of unaffected carriers.     

Keratinase production and keratin degradation by a mutant strain of Bacillus subtilis

A new feather-degrading bacterium was isolated from a local feather waste site and identified as Bacillus subtilis based on morphological, physiochemical, and phylogenetic characteristics. Screening for mutants with elevated keratinolytic activity using N-methyl-N＇-nitro-N-nitrosoguanidine mutagenesis resulted in a mutant strain KD-N2 producing keratinolytic activity about 2.5 times that of the wild-type strain. The mutant strain produced inducible keratinase in different substrates of feathers, hair, wool and silk under submerged cultivation. Scanning electron microscopy studies showed the degradation of feathers, hair and silk by the keratinase. The optimal conditions for keratinase production include initial pH of 7.5, inoculum size of 2% （v/v）, age of inoculum of 16 h, and cultivation at 23 ℃. The maximum keratinolytic activity of KD-N2 was achieved after 30 h. Essential amino acids like threonine, valine, methionine as well as ammonia were produced when feathers were used as substrates. Strain KD-N2, therefore, shows great promise of finding potential applications in keratin hydrolysis and keratinase production.     

列车感应通信信道的建模分析

首先建立了具有屏蔽导体的多导体传输线和地面上方单传输线的数学模型,在此基础上建立列车感应通信信道的模型,并利用矩量法进行数值分析。     

创建智能体系统的软件工程方法研究

研究作为数字世界中计算和应用软件系统构造单元的软件智能体构建与开发。提出由 (1)智能体理论模型 ;(2 )以之为概念框架的软件系统逻辑结构模型 ;(3)基于结构模型 ,采用统一建模语言UML实现的应用程序框架三部分组成的方法体系。这三个部分既具有内在机理联系又有过程时序约束 ,它们分别支持软件工程的分析、设计与实现各阶段。预期该方法体系的成功运用将有利于软件智能体系统开发的规范化和标准化 ,进而提高智能体系统开发效率并促进成果共享和软件重用     

大型电子系统工程软件可靠性评估方法初探

本文探讨了大型电子系统工程的软件可靠性评估方法问题。从软件可靠性模型,可靠性实验数据的收集,以及可靠性数据估值的准确性,可靠性数据的检验等方面进行了研究。最后,提出了一般的评估步骤。