应用S7-200PLC改进锅炉控制系统

因原有锅炉控制系统存在不足，加之工作人员操作失误，在锅炉运行时故障频繁发生。本文用S7—200PLC对原锅炉的控制系统进行了改进，该系统采用了高性能火焰检测及控制器，提高了锅炉点火、运行的安全性和生产效率。     

基于神经网络的火焰燃烧稳定性算法研究

本文旨在研究锅炉火焰燃烧的稳定性问题,提高锅炉燃烧火焰的检测准确度.针对锅炉燃烧监控系统所采集的火焰动态图像进行分析来检测锅炉内火焰燃烧稳定性,燃烧受影响的火焰出现短时脉动时,传统的基于灰度方差的检测方法不能避免火焰脉动的影响,造成对锅炉内燃烧稳定性检测准确度不高的问题.本文提出一种基于神经网络的火焰燃烧稳定性检测方法,选取与火焰稳定性直接相关的多个特征作为神经网络的输入向量,对样本多次训练能去除杂质燃烧或调峰引起的微小脉动的影响,克服了传统方法检测准确度不高的问题.实验证明,该方法能够有效避免杂质和调峰对燃烧的影响,对锅炉内的燃烧稳定性做出准确检测.     

图像火焰检测系统在电厂锅炉上的应用

介绍了安庆石化热电厂#5锅炉增装图像火焰检测系统的配置，各组成部分的功能、特点及对锅炉安全运行的作用。     

电站锅炉数字图像火焰检测系统设计与实现

针对现有的锅炉火焰检测系统主要以开关逻辑量为主以及现有的图像检测系统的缺点，设计了基于通用视频采集硬件的锅炉火焰图像检测系统。对火焰图像进行了预处理并给出了一种最佳的分割算法，引入了针对不同特征的重要性修正因子。为了适应多炉型、多煤种、复杂工况的情况，对所提出的自适应聚类中心主动优化算法做了分析描述。给出了系统的软件模块图，并对各模块的功能做了分析，并得出结论。     

热电站锅炉安全保护与火焰检测

简要阐述热电站锅炉安全保护系统及其关键技术-火焰检测器的原理与特性,讨论在实际应用中火焰检测的稳定性和可靠性问题。通过对炉膛火焰的提取,分析与处理,使炉膛灭火保护装置的功能得以扩大和延伸。这一技术对热电站锅炉的火焰检测及灭火报警起着关键作用,该项技术目前已获广泛应用。     

基于向量量化网络的火电厂炉膛火焰检测

通过对火力发电厂锅炉炉膛火焰检测装置及炉膛燃烧器的分布位置进行分析,结合神经网络的LVQ结构及MATLAB编程,介绍一种火焰检测的新方法.该方法首先通过火焰检测装置把采集到火焰有无的光信号转换成电信号,然后再经过滤波放大等环节把电信号转换成数字信号,送入微机用MATLAB编写的LVQ程序进行检测,根据仿真的数据及曲线可以看出此种方法能够及时准确地为运行人员提供报警信息,达到预先设定的目标.     

电站锅炉数字图像火焰监控系统设计与实现

针对现有的锅炉火焰检测系统主要以开关逻辑量为主以及现有的图像检测系统的缺点，设计了基于通用视频采集硬件的锅炉火焰图像检测系统。采用计算机软件对火焰图像进行了预处理给出了一种最佳的分割算法。引入了针对不同特征的重要性修正因子。同时为了适应多炉型、多煤种、复杂工况的情况，对我们提出的一种自适应聚类中心主动优化算法做了分析描述，也给出了系统的软件模块图，并对各模块的功能做了分析。最后给出了我们的实验结论。     

600MW机组锅炉火焰检测装置存在的问题分析及改进

对哈三电厂600MW机组锅炉火检一直不稳定的原因进行了详细的分析，同时结合现场实际情况，对原火焰检测装置提出了科学的改进方法。对火检探头进行优化设计，并对改进后火焰检测装置现场应用情况进行了总结．     

美国COEN智能一体化火检系统在600MW锅炉的应用

火焰检测系统是炉膛安全监控系统（FSSS）的重要组成部分,它能否可靠地运行直接影响锅炉的安全。因此,以美国COEN火焰检测系统为例,分析它在广东靖海电厂2×600MW机组锅炉的使用状况和故障。     

燃煤锅炉火焰相关检测的信号处理方法

炉膛灭火是引起燃煤锅炉爆然的一个重要原因，因此利用火焰检测器检测火焰的燃烧工况显得特别重要，相关检测法是近年来提出一种较好的火焰检测方法，对相关检测器所检测到的信息的处理方法是关系到其应用能否成功的一个重要方面。本文提出了一种较为实用的信号处理方法－数学滤波器的设计方法和极性相关算法，并给出了仿真结果。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with