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1.
为制定符合客流的线路公交调度方案,增大公交出行吸引力,减少私家车出行碳排放,有必要提出精确的线路乘客上、下车站点识别方法,获取精确客流数据,为公交调度提供精细数据支撑。本文以福州市常规公交多源数据为基础,针对数据缺陷提出系统时间误差修正及站间缺失数据修复的数据预处理方法。在此基础上,提出乘客刷卡时间与公交到离站时间匹配的上车站点识别方法。将乘客出行行为按照是否具有出行规律,提出基于乘客出行规律的乘客下车站点识别方法及综合出行距离、换乘能力、出行吸引强度、周围土地利用性质等因素影响下的乘客站点下车概率识别方法。最后,以福州市125路公交数据为例,将识别数据与实际调查数据对比,验证识别方法的准确性。研究结果可为城市公交客流OD调查提供数据挖掘方法,减少传统调查产生的人力物力,以及为公交企业运营调度提供数据支撑。  相似文献   

2.
以某市连续5日全天公交阶梯收费刷卡数据、公交出行GPS(global positioning system)数据及公交站点数据为基础,结合出行链算法与随机森林网络,构建了一套公交下车站点融合分析模型.在模型中,首先匹配GPS数据与公交站点数据,确定不同时刻的公交到站信息,再以乘客上车站点位置、出行频率、活动空间、下车点...  相似文献   

3.
OD矩阵作为交通客流数据可视化的重要方法,是公交系统评价和优化的重要依据.提出了一种基于云计算的OD矩阵构建框架,在此框架下利用云计算优异的存取速度及计算性能,实现了对公交历史数据的筛选、预处理、变换、数据挖掘、解释评价等操作.此外,还提出一种综合了追踪乘客出行行为规律和估计站点热度的OD矩阵构建模型来实现对乘客下车站点较为精确的估计.算例分析表明,根据该模型计算得到的各站点下车人数结果能较好地拟合实际出行OD矩阵.  相似文献   

4.
为提高公交换乘识别的精度,将IC卡和GPS数据融合推断得到乘客上车站点和下车站点及下车时间,在此基础上根据居民公交出行的特点及过程,从时间角度和空间角度来判断公交换乘行为。时间角度判断是从乘客站台候车时间及乘客站台候车时间段内是否乘坐第一辆目标线路车辆两个方面进行换乘行为识别。空间角度判断通过两个参数即迂回系数和直达系数来进行换乘行为的判断。最后,与只从时间角度识别的方法进行了对比。结果表明:考虑空间因素的识别方法更为合理全面。  相似文献   

5.
以往通过人工调查获取公交车出行OD的方法既费时又费力,随着城市公交系统的完善,使用公交IC卡已经成为常住居民的习惯,通过对IC卡数据进行挖掘,结合集合论的数学方法来实现居民公交OD出行信息的提取,不但节省了人力物力,在精度上较人工调查也要更高。方法通过数据挖掘,分别建立IC卡刷卡记录表、公交车到站信息表及公交线路信息表,以此可以准确获取IC卡的上车信息,同时在假设公交出行链闭合(前后两次出行均为公交出行)的前提下,以集合论为基础建立了相应的下车站点推算模型,实现了OD出行信息的提取。  相似文献   

6.
当前一票制的公交IC卡收费系统无法获取乘客的上车站点和下车站点,为公交线路客流量分析造成了一定困难。本文通过充分研究IC卡数据以及GPS数据,构建了以IC卡数据为基础的乘客上下车站点匹配模型,挖掘数据中包含的公交运行特征以及乘客出行特征。模型同时考虑封闭式公交出行链以及非封闭式公交出行链,并采用二分算法以及多概率融合的方法在乘客乘车特征基础上推测乘客的上下车站点,可有效提升公交的高效化运行管理。以承德市7号线路为例进行验证,采用线性回归方程对上下车站点匹配结果进行分析,相关系数高达0.977,校验回归方程系数值为0.978 5。结果表明该模型可实现对公交车乘客上下车站点的有效匹配,具有较好的可靠性。  相似文献   

7.
用出行链方法推算的下车站点的记录可作为历史出行数据集,而现有的研究在对出行链断裂的记录进行下车站点推算时使用的历史数据集较小,造成可推算下车站点数据量少、准确率低的缺点.提出基于历史出行记录扩充的公交乘客下车站点推算方法 .首先,使用多源数据集成的出行链方法进行下车站点推算,将已确定下车站点的数据作为历史数据集;其次,基于个人历史相似出行的方法对于未确定下车站点的记录进行推算;最后,选择同线路同站点上车的其他乘客的IC卡记录作为每条未识别下车站点记录的群体历史出行记录,并基于相似出行行为规律进行下车站点的推算.该方法增加了可推算下车站点记录的数据量、提高了推算的准确率.以厦门市为例的实验结果表明:在历史出行记录生成时,使用多源数据可比单源数据多生成3. 48%历史出行记录,推算准确率提高1. 99%;在历史出行记录选择时,选择群体历史出行记录分析得到的历史相似出行行为规律,可对前两种方法无法确定下车站点的所有记录进行推算,占全部待推算记录的21. 81%,其中5. 37%记录的下车站点推算正确.  相似文献   

8.
为满足城市轨道交通运营组织进行客流管控和行车调度的实时需求,提出了基于乘客OD时空特征的出行目的地在线预测方法。通过分析定义乘客OD时空特征矩阵,以乘客个体的历史自动售检票系统(AFC)数据为训练样本,提出了基于行程密度聚类的乘客OD时空特征提取方法。分析制定乘客实时进站刷卡信息与其OD时空特征矩阵的匹配规则,基于3种匹配情况分别提出了相应的目的地实时预测方法。以南京市轨道交通AFC数据为实例进行验证,结果表明本文提出的预测方法在高峰时段预测准确率、全天预测稳定性等方面效果良好,可为地铁运营组织提供参考。  相似文献   

9.
葛柯娜  马涛  王晶  陈聪  孙艺萍 《科技资讯》2014,12(18):23-24
利用基于Android平台的公交跟踪系统公交路线跟踪系统,乘客可以提前得知附近所有公交的线路,以及最好情况下要达到本站的时间及乘车人数;公交车上可以通过键盘手动设置乘客人数的上限值,通过乘客上车刷卡和下车刷卡的记录或者通过称重传感器获得重量得到乘客人数,在LED显示器实时显示车内的乘客人数并且同步到手机客户端。当客车发生超载时,系统发出声光报警,利用传感器与互联网的结合获得每辆公交现客载量。  相似文献   

10.
目前起讫点(origin-destination,OD)挖掘方法普遍存在无法并行分析多条线路、低效率、预测率不足的问题。考虑到Hive在海量数据上的查询性能优势,基于Hive实现了OD挖掘,克服了上述问题。基于时间阈值匹配上车站点,失配记录基于站点上客数再次匹配。基于表连接的出行链算法预测下车站点,预测失败的记录基于概率进行两次预测。以石家庄2018年1月1日—2018年3月27日的IC卡刷卡数据和调度数据进行OD挖掘,在清洗后的11 312 505条出行记录中挖掘出11 270 037条OD记录,预测率达到99.6%,出行与吸引校验质量较高,Hive并行调优开启后耗时17 829.04 s。可见该方法满足生产环境中离线挖掘OD的业务需求。  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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