基于时间序列分析的动态变形预报

对变形体的变形趋势做出预报,是变形监测的主要任务之一.时间序列分析能顾及各期数据间的统计相关性,通过建模实现变形体的动态变形预报.鉴于AR模型估计参数时有递推公式,且工作量小,故在介绍时间序列模型的基础上,结合变形监测实例,讨论了AR模型的建模过程,并采用AR模型实现了变形的动态预报.     

基于贝叶斯模式平均与标准化异常度的东江汛期降水预报

考察贝叶斯模式平均(BMA)对第二代气候预报系统(CFSv2)在东江流域汛期月降雨量预报的订正效果,同时引入标准化异常度(SA)指标识别异常的降雨值,分别进行SA的确定性预报以及集合预报,通过建立SA和BMA结果之间的联系构建一个较为完整且精度较好的降雨预报模型,提高东江流域中长期降雨预报的精度。主要结论如下:1BMA50%以下的分位数不具有预报作用,75%分位数具有最优的预报效果。但BMA还存在不足之处,常表现为对极端降雨的低估;2利用CFSv2集合平均值进行SA计算时,SA严重偏小,可能说明CFSv2存在系统性误差。对CFSv2原始预报分别进行伽玛函数订正以及多项式订正后,降水预报成功指数(Ts)和异常值报对的次数有明显地提高,但预报偏差(Bs)也相应地增大;3 SA与BMA之间大致可建立如下的关系,即当SA判断会出现异常值时可选择95%分位数的预报值,相反则选择75%分位数预报值。     

建筑物沉降的时间序列分析与预报

首先对建筑物沉降数据序列进行了平稳化处理,然后研究了平稳化序列的建模和预报方法,最后结合建筑物沉降监测的具体实例进行了时间序列的分析与预报.结果表明:将时间序列分析方法应用于建筑物沉降监测,具有建模容易、计算简单、预报快速的特点;时间序列分析方法对建筑物沉降具有较高的模型拟合及预报精度,尤其是短期预报,效果更佳;应尽量避免使用时间序列进行中长期预报,要根据实测数据对所建模型进行实时更新.     

陕西省苹果产量品质预报系统

采用面向对象的开发方法,在Windows 32位操作系统环境下,用Delphi与SQL Server成功开发了Client/Server结构的一套苹果产量、品质预报业务系统.该系统主要由数据库管理、因子分析、产量预报模式、品质预报模式、系统辅助功能模块5部分组成.其主要特点是操作简易、结果客观定量.建模时考虑了影响统计模式预报精度的多重因素,筛选因子过程严格,建模方法多样,使得建立的模型比较稳定可靠.     

RBF网络在线建模方法在热误差实时补偿技术中的应用

应用径向基(RBF)神经网络模型的学习性能,对一台数控加工中心的主轴温度与主轴径向热误差关系分别进行离线建模与在线建模对比研究,并将2种建模方法用于实例分析.结果表明,RBF神经网络模型能够反映数控机床的热特性,准确实时预报机床热误差.当工况发生较大变化时,在线建模能够及时补充系统信息,更好地反映机床系统热性能,从而精确预报机床的热误差,提高了误差补偿效果.     

加工装置的精度动态损失贝叶斯建模预报

针对测量过程中需要对数据量较少的非平稳性精度进行随机序列的建模预报,提出了贝叶斯动态测量精度序列的预报方法.该方法不要求较大的数据量,对序列平稳性无限制,并以实例验证了贝叶斯预报方法的适用性和可行性.     

预测地铁施工中地表变形的动态系统方法

提出了基于自回归（AR）模型对时间序列统一建模的新观点和方法,可大大减少计算量,并在微机上编程实现,以实例对动态模型与静态模型分别作了应用比较,结果表明,时间序列分析动态模型是系统分析的重要方法,是统计预测中的高级预测方法,预测精度高,用途广泛,而静态模型适合于内插,不适合于外推预报。     

非线性分位点回归方法在大坝安全监测中的应用

基于分位点回归模型比最小二乘回归模型具有更强的统计分析能力,将参数估计的MM算法和统计诊断中的影响度量MM距离运用于大坝水平位移的统计模型,并给出了应用实例.结果表明,分位点回归方法受异常点影响较小,训练及预报结果优于最小二乘法,将其应用于大坝水平位移安全监测,可提高预报模型的预测精度,能更好地对大坝运行性态进行分析.     

时序相似集合预报法及其在天气预报中的应用技巧

利用VB语言成功建立了应用地面自动站数据的多站多要素时序相似集合预报法,并结合实例详细阐述了相似集合预报图在天气预报应用中的技巧,突显了地面数据相似集合预报在短时、短期预报业务中不应忽视的参考性价值.     

2021年蚌埠市6种空气质量预报模式的检验

本文把2021年安徽省空气质量预报预警平台采用6种空气质量预报模式的具体预报情况,与2021年蚌埠市空气质量实测值进行对比检验,分析了6种模式在蚌埠市的预报效果。结果表明,集合预报、CMAQ、统计预报模式在24 h时效内,集合预报、CMAQ、CAMX模式在48 h、72 h时效内的AQI预报中具有较高参考价值;在除冬季外的24h时效AQI预报中,集合预报、CMAQ、统计预报准确率较高,而NAQPMS则在冬季准确率较高;仍需通过人工综合分析,进一步提高AQI范围预报准确率。     

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