基于自编码网络的空气污染物浓度预测

深度学习为城市空气污染物浓度预测提供了更为强大的数据拟合能力,为空气污染预测提供全新的智能计算方法.为此,提出了一个基于自编码神经网络的污染物浓度预测模型AEPP(auto-encoder-based pollutant prediction).该模型包括编码器和解码器两个部分.其中,编码器用于提取出时间序列污染物浓度数据分布特征,即语境向量;解码器利用提取的特征预测未知时间内污染物浓度数据.模型中编码器和解码器采用多层LSTM(long short-term memory)模型结构,实现长时间依赖预测目标.实验表明,提出的模型可以提高对污染物浓度的预测水平.     

基于Hadoop的大气污染物质量浓度预测系统设计

针对大气污染物质量浓度预测及其大规模数据计算问题,设计了一种基于随机森林算法的污染物质量浓度预测算法,采用MapReduce并行计算框架并行化计算空气质量指数,实现了基于Hadoop平台的空气污染物质量浓度预测系统.通过试验比较了基于随机森林算法和基于线性拟合算法的计算结果,显示本算法能够有效降低大气污染物质量浓度的预测误差.     

森林经营可视化管理系统设计与实现

使用C#和Mogre为开发环境,设计并实现了融合森林对象模型、生长模型、森林环境模型、GIS数据等为一体的交互式森林资源管理和经营的可视化平台。系统实现了二维,三维图层交互管理、可视化林分构建、可视化森林环境漫游、可视化林分生长预测、可视化森林经营等功能。最后以森林经营理论为指导,以湖南省黄丰桥国有林场为实验区域,以更新造林为例,模拟了以杉木人工林为主要树种的林区的经营方案的制定和经营措施可视化的过程,并在此基础上对小班内更新的林木进行了生长预测模拟。     

溢油及化学品泄漏预警平台开发研究

基于非静压假设建立了三维潮流及可溶性物质扩散数学模型,在水动力数值模拟基础上,以粒子法预测溢油扩散过程,针对模拟计算结果实现了对流场、污染物及油膜扩散的可视化,建立了图形化界面的预警平台。通过在南港实际工程中的应用,证明平台开发的成功及实用性。     

水污染模型EFDC在环境污染中的应用研究探讨

本文是以某河流为研究对象,利用EFDC模型的有毒物质模块,基于GIS平台实现水污染的动态模拟。系统把参数设置、模型计算、结果展示等采用可视化的方式集成到系统中,使得用户操作方便快捷。最终计算的结果以时间为线索动态地展示在系统中,同时又能够实现监测点位污染物浓度动态的展示。系统可以应用到河流或湖库的保护中。     

基于多聚合过程神经元网络的宁东大气污染物浓度预测研究

已有的基于人工神经网络对大气环境质量预测的研究大多只考虑空间特性,因此,无法准确刻画大气环境中污染物浓度随时间的动态变化规律,更不能实现影响污染物浓度诸因子在时间维上的有效预测。鉴于此,主要在时间、空间上对多聚合过程神经元网络模型进行多次训练与学习,并将训练好的模型对宁东能源化工基地大气环境中污染物SO2的浓度进行预测。仿真实验表明:多聚合过程神经元网络对于大气环境中SO2浓度具有较好的预测能力。     

城市高架路沿侧细颗粒物的垂直分布特征研究

以上海市高架路为对象,通过移动设备开展数据采集,建立广义加性模型,对高架路细颗粒物(PM_(2.5))浓度的垂直分布及其与微观尺度下的交通、气象、位置等因素之间的关系进行了系统研究,并将原始影响因素的主成分分析结果作为输入变量,提出基于主成分分析法(PCA)的高架路交通污染物浓度垂直变化的神经网络预测模型(PCA-BPNN).结果表明:高度、相对湿度和交通流量对PM_(2.5)浓度垂直变化有着显著影响;PCA-BPNN模型能够较好地处理污染物扩散的非线性问题,消除变量间多重共线性,有效弥补污染物垂直扩散模型在道路微观尺度上预测的不足.     

多功能破拆机器人工具头换装可视化研究

针对多功能破拆机器人危险工况作业与远程工具头换装问题,提出一种基于机器人操作系统的可视化换装方法。该方法可实现传感器数据采集、工具头位姿检测、机器人运动状态三维可视化、数据处理与存储等功能。首先分析可视化平台的组成及基本原理,建立机器人运动学模型简述运动学理论、液压缸与关节角的换算关系,给出机器人运动状态的可视化;然后分析工具头位姿获取及可视化,以Apriltags作为视觉基准系统,利用视觉检测实现工具头定位完成工具头的可视化;最后搭建实验平台测试可视化平台的实用性和稳定性。结果表明可视化平台能够有效地完成危险工况作业状态的实时监测与机器人远程工具头换装任务。     

基于CALPUFF的大气污染预测软件优化

该文在CALPUFF源代码的基础上,使用C#语言开发了基于该模型系统的计算软件,解决现有CALPUFF参数设置复杂、输入文件编写困难及配套软件无法进行中文操作的问题,并在GIS的基础上实现了大气污染物在空间扩散情况的可视化输出,为使用CALPUFF对大气污染物扩散情况进行预测和模拟提供了更加方便可行的手段。     

应急管理可视化多元信息系统构建若干问题研究

基于应急管理的4R理论构建了应急管理系统功能模型和结构模型,提出了基于资源层、状态层、决策层和操作层表达的四层结构应急管理可视化多元信息系统模型,并给出了多元信息可视化表示方法示例和分层递阶可视化融合和应急决策模型.     

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.     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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