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1.
安全监测在地铁建设和运营中占据着举足轻重的作用,如何建立科学完备的地铁安全监测方案和针对监测数据进行有效合理的分析是当前研究的重点之一.基于合肥市某地铁车站建设工程,主要介绍了该地铁车站工程的监测方案,并采用灰色系统理论建立GM(1,1)沉降数据预测模型.结果显示,该模型取得了良好的拟合和预测效果,为地铁监测数据分析提供有效的方法.  相似文献   

2.
提出一种基于BP神经网络的城市地下轨道交通公共区温度预测方法,结合客流量、外部环境、内部设备等影响因素,针对长三角区域地下轨道交通公共区一年四季的温度建立一个预测模型,分析各类影响因素对地铁地下环境的影响,进行地铁通风、空调设施的开启对比.研究结果表明:该预测模型与实测温度的平均误差为1.4℃,相关系数为0.895,误差分布呈正态分布,可以为地铁运营节能减排提供参考.  相似文献   

3.
为提高城际铁路车站短时客流量预测的准确性,本文设计了一种基于双向长短期记忆网络(Bi-LSTM)的预测模型.首先分析了广珠城际铁路车站日客流量的时间分布规律,发现各车站日客流量存在着相似的分布特征,但工作日、周末和节假日客流量呈现出较大差异.以广州南站、珠海站以及小榄站3个车站的进站客流为例,选择时间窗步长为2和4分别...  相似文献   

4.
分别从优化算法集成神经网络及将数据聚类后按类建模两方面建立3种模型对地铁车站空调负荷进行逐时预测,结果表明:同一物理量对地铁车站空调负荷所产生的影响程度随时间呈现某种动态变化特征,根据历史数据定量分析这些特征,对精准筛选模型输入参数、提高模型预测精度大有裨益。在3种模型中,粒子群优化算法-神经网络(PSO-BPNN)和果蝇优化算法-神经网络(FOA-BPNN)预测的平均相对误差(MAPE)较单纯神经网络(BPNN)分别降低25.87%和40.08%,聚类-神经网络(Kmeans-BPNN)预测的MAPE比PSO-BPNN及FOA-BPNN分别降低61.12%和51.90%。说明在同等情况下,优化算法集成模型比单纯BPNN预测精度更高,而当区分实际负荷变化特点后,采用聚类后建模比优化集成建模效果更佳。  相似文献   

5.
改进的季节性指数平滑法预测空调负荷分析   总被引:9,自引:0,他引:9  
根据空调日总负荷和日平均气温之间的较强相关性,对经典的季节性指数平滑法预测模型中的水平因子项进行修正,并去掉趋势因子项,得到了改进的季节性指数平滑预测模型.以上海某医学中心空调系统作为该空调负荷预测模型的应用实例,在整个预测期内模型平均预测误差为8.8%.这表明改进的季节性指数平滑法适合于办公类建筑空调负荷的预测.  相似文献   

6.
为了对地铁短时客流流量进行准确预测,建立了一种基于深度学习的地铁短时客流预测方法。通过分析地铁的客流数据,发现周一至周四、周五以及周末的发展模式存在一定的差异。依据该发现,基于深度学习的理论框架,建立了双向长短期记忆网络的地铁短时客流量预测模型。最后以广州体育西路地铁站数据为例进行预测分析,并将预测结果与决策树模型、支持向量机算法以及长短期记忆网络的预测结果进行对比分析。结果表明,双向长短期记忆网络全面优于其他预测算法,且该算法的平均预测精度超过90%,对地铁运力的合理配置等有一定的应用价值。  相似文献   

7.
提出了一种基于相空间重构与支持向量机预测公交客流量的新方法.应用互信息法计算公交客流量时间序列的最优时间延迟;应用Ca0氏方法计算其最佳嵌入维数;然后计算出最大Lyapunov指数,证实客流节存在混沌现象.建立相空间重构-支持向量机预测模型并确定训练样本对,对公交客流量数据进行预测.实例证明,该方法能有效地进行客流量预测.  相似文献   

8.
结合聚类分析和小波神经网络模型,提出一种二阶段空调负荷建模方法,以提高空调负荷预测精度.首先利用K均值聚类算法将原始负荷样本数据依据其统计分布特性划分为若干簇类,以降低数据相关性对建模精度的影响;然后基于对每个划分簇类所属的样本数据建立相应小波神经网络空调负荷预测模型.最后基于De ST平台模拟数据,将构造的小波神经网络预测模型运用于福建某办公大楼的逐时空调负荷预测.通过对比均方根误差(RMSE)和平均绝对误差(MAPE),结果表明该模型的预测精度明显优于传统单一的小波神经网络和BP神经网络模型.  相似文献   

9.
为提高电力负荷预测的准确性,提出蝙蝠算法优化极限学习的电力负荷预测模型.首先收集电力负荷历史数据,然后采用蝙蝠算法对延迟时间和嵌入维以及极限学习的隐含层结点数目进行优化,利用电力负荷历史数据进行重构,最后采用最优隐含层结点数目的极限学习机建立电力负荷预测模型,并采用具体数据仿真测试.实验结果表明:模型建立了整体性能优异的电力负荷预测模型,提高了电力负荷的预测精度.  相似文献   

10.
屏蔽门模式环境控制的特性及经济分析   总被引:1,自引:0,他引:1  
介绍地铁环境控制的3种模式,分析屏蔽门模式环境控制的特性及负荷模拟计算,对3种地铁环境控制模式进行经济分析比较,结果表明,屏蔽门模式是一种最经济的地铁环境控制模式.屏蔽门隔离隧道内热空气与车站内空调冷气之间的交换,使车站成为一个独立的空调场所,可以显著降低车站空调的运行能耗,为乘客提供一个舒适、安全的候车环境.一个典型车站的国产化屏蔽门系统投资费用在1000万元左右,可节省470万元的车站土建及制冷空调设备投资,且每年可节省电2×106kW·h以上,预计5年内就可收回成本.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
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-  相似文献   

18.
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-  相似文献   

19.
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  相似文献   

20.
<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  相似文献   

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