空调列车车厢内CO2浓度的模糊控制

以列车车厢内CO2浓度为控制对象,实现对新风量的控制.在车内CO2浓度控制系统中,应用模糊控制理论,将车内CO2浓度与设定浓度之间的误差以及误差变化率作为控制系统的输入量,新风阀门开度的变化作为输出量,并建立各输入、输出量的模糊集、论域、隶属函数以及模糊控制规则;确定列车硬座车厢内CO2浓度与时间、新风量之间的函数关系式,并应用所建立的模糊控制系统对列车硬座车厢内的CO2浓度进行模糊控制仿真实验,研究新风量与车厢内CO2浓度之间的变化关系.研究结果表明:运用模糊控制理论可对车内CO2浓度实现稳定、可靠的控制,为改善车厢内空气品质提供了一种新方法.     

铁路客车空调新风量的确定及控制

对于铁路系统来说,保证空调客车乘坐的舒适度及降低能源消耗、减少空调客车的运行成本,具有重要的意义.针对空调客车新风量的确定进行了分析,并采用模糊控制技术,以车厢内二氧化碳浓度偏差及偏差变化率作为模糊控制器的输入,进行新风量的合理控制,为改善车厢内的空气品质提供了一个切实可行的方法.     

重庆地区商场CO2浓度测试

在商业建筑设计时，室内CO2浓度的数值作为新风量设计的依据，它直接影响到商场内的空气品质。同时，受CO2浓度控制的新风量，也影响到空调总负荷的多少，设计中为在满足室内空气品质的基础上达到新风量最小，同类型商业建筑中CO2浓度值是重要的参考数据。为此作者实测了重庆地区某大型商场，在分析CO2浓度测量数据的基础上，得出目前重庆地区商业建筑室内CO2污染比较严重的结论，并提出了设计中应加大送风量，同时改进送排风，合理分配室内气流的意见。     

基于NN-PID算法的变风量空调系统空气品质控制

目的针对典型会议室环境,基于需求控制通风策略,对变风量中央空调系统房间空气品质控制进行研究。方法以典型的会议室环境为研究对象,分别建立空调新风系统模型及房间CO2浓度模型;设计NN-PID(神经网络-PID)算法,并进行控制与仿真;在变风量空调实验平台上进行验证。结果所设计的NN-PID算法能有效利用神经网络训练过程,在线自整定PID参数,控制效果优于传统PID算法。结论根据室内CO2浓度变化控制新风量,能很好地适应室内CO2浓度的动态特性,提高室内空气品质。     

基于PMV指标的列车空调模糊控制研究

采用热舒适控制不仅能满足人体的舒适感,而且还能满足系统节能的需要.对热舒适控制中的各变量进行了分析,采用模糊控制技术,选择空气温度作为直接受控的参数,并通过调节送风量来实现.以车厢内PMV值的偏差及偏差变化率作为模糊控制器的输入,进行新风量的合理控制,使列车空调的控制随着人体舒适感的变化而变化.     

旅客列车硬卧车厢内空气质量的数值模拟

采用稳态不可压缩雷诺时均N-S方程、kε湍流模型,对YW25K型空调硬卧车厢内空气质量进行数值模拟。采用立方体代表乘客,以人体呼出的CO2作为代表性污染物,以PMV和车厢内CO2相对浓度为基础,提出了评价车厢内空气质量的新指标,利用该指标对硬卧车厢内各铺位的空气质量进行了评价。计算结果表明,送风速度对车厢内空气质量有较大影响,增加送风速度有利于改善车厢内各铺位的空气质量,但过大的送风速度对车厢内空气质量不利;硬卧车厢内采用条缝送风方式、送风速度为2.5 m/s时,车厢内空气质量最佳,可同时满足热舒适性要求和保证良好空气品质。     

过渡季假日上海地铁城郊线路车厢内空气环境的实测

在过渡季节,乘客是地铁车厢内部主要污染源和热源.为了解上海地铁城郊线路车厢空调系统的控制状况,以上海市轨交系统9号线为城郊线路代表作为实测对象,在以国庆节为代表的过渡季假日,对车厢内空气温湿度、CO_2浓度和人员密度进行了连续测量.实测结果表明,假日车厢内人员密度在0.3~3.0人/m~2范围内波动;当空调系统运行时,车厢内部空气温度在正常范围内波动,几乎不受人员密度影响;车厢内CO_2浓度随着人员密度增大而明显升高,但80%的时间CO_2浓度低于0.15%,通风排污效果基本能够满足假日地铁运行状况的要求.     

我国列车空调的现状及其节能途径探讨

对目前我国列车空调的现状进行了分析，指出列车空调的能耗是惊人的。对列车空调的节能途径进行了探讨，并针对列车空调的新风量进行了分析，提出用二氧化碳浓度法来合理控制新风量，既可以满足旅客对舒适度的要求，又能达到节能的目的。     

商场空调设计中客流量和新风量取值的探讨

文中根据长沙市某大商场的调查对客流量、新风量的取值进行探讨。提出在空调冷热负荷计算时 ,冬夏客流量的取值应分别计算 ,以CO2 浓度控制新风量 ,并采用变风量新风系统的看法     

对变风量空调系统的探讨

变风量空调系统具有节约能耗、空调品质高、运行维护简单等突出优点,已获得了越来越广泛的应用.空气处理机组是变风量空调系统中的关键空调设备,对它的运行控制直接影响到变风量空调系统的成败和节能的效果.在系统设计过程中,空气处理机组控制方案与控制参数的确定.应引起空调设计师与自控设计师的高度重视.变风量空调系统中空气处理机组的控制功能,除应具备常规定风量空气处理机组中的各类保护与报警功能外,还必须具备送风温度控制功能、送风量控制功能、排风量控制功能、新风量控制功能等.为充分发挥变风量空调系统的优势,自控运行方案还应分冬季、夏季、过渡季三个运行工况设定.本文论述变风量空调系统中空气处理机组的送风温度、送风量、新风量等参数的控制方式和设定值的选择,提出了完整的变风量空调系统中空气处理机组的控制方案,并讨论变风量空调系统过渡季运行方案.     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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