基于大数据的高速公路流量优化策略研究

阐述大数据在交通监测、预测与管理方面的最新进展,分析数据的采集、处理和分析在高速公路流量管理中扮演的关键角色。通过构建理论模型并进行策略分析,运用大数据技术进行交通流量分配和控制的各种策略,有利于提高道路利用效率,并有效减缓交通拥堵现象。进一步评估在交通流量优化中运用大数据技术所面临的挑战,并提出相应的解决方案,为未来的交通管理策略和政策制定奠定坚实的理论与实证基础。

基于递归框架的高速公路交通流量实时预测方法

实时与准确的断面交通流量预测是实现高速公路智能化管理与控制的基础。高速公路交通流量预测要求对数据噪声进行有效处理,且需要满足实时性需求。然而,少有研究从实时性的角度对高速公路交通流量预测的准确性进行改善。研究了结合自适应卡尔曼滤波与长短时记忆神经网络(long short-term memory,LSTM)自编码器的高速公路交通流量递归预测框架,可以满足智能交通系统的实时性与准确性需求。收集高速公路的交通流量和速度等历史数据,应用卡尔曼滤波方法进行数据平滑,以提高原始数据的可预测性能;引入无监督机器学习算法LSTM自编码器对交通流量的时变特征进行建模,以提高模型的运算效率;考虑到高速公路交通流量预测的实时性需要,进一步提出递归预测框架,用LSTM自编码器的预测值代替卡尔曼滤波值;根据获取的实时数据,执行自适应卡尔曼滤波算法以修正当前的最佳状态值,并将该修正值输入LSTM自编码器进行迭代预测。选取美国明苏尼达双子城高速公路的实测交通数据进行案例分析,结果表明:所提出的高速公路实时交通流量递归预测框架在计算成本与预测精度2个方面具有相对竞争优势,模型预测的平均绝对百分比误差为5.0%,优于卡尔曼滤波和LSTM自编码器组合模型的7.4%;模型训练时间为85 s,低于标准LSTM模型的101 s。

基于零膨胀负二项回归模型的高速公路卡口交通流量与事故分析

本文借助高速公路卡口数据,分析高速公路路段一段时间内过车数、过车速度等交通流量信息对事故起数的影响。通过对交通流量变量的分析与筛选,利用泊松回归、负二项回归、零膨胀回归等模型对数据进行拟合分析,发现对于引起交通事故较为显著的交通流特征,并选取拟合效果最好的模型。可结合高速公路卡口流量数据,对当前道路安全形势做出预测,有助于公安交管部门提前采取针对性措施,提高道路安全水平。

CS优化BP神经网络的高速公路流量预测

随着高速公路交通控制和出行诱导需求的日益增加,对高速公路交通流量的预测提出了更高的要求。为了提高预测的精度,提出了改进的布谷鸟搜索(cuckoo search,CS)算法优化BP神经网络的高速公路流量预测模型(Weighted value of T dynamic disturbance CS-BP,WTCS-BP)。利用高速观测站的信息采集系统收集车流量信息;离散为时间序列,构建学习样本;利用BP神经网络对采集的样本进行训练,并采用改进的CS算法对网络参数进行优化;建立高速公路交通流量的预测模型。最后通过仿真实验进行测试。结果表明,该模型的拟合度较其他对比模型更接近实际流量。提高了预测的准确性,对高速公路出行起到有效的指导作用。

基于高速公路流的江苏省交通网络地域分异及影响因素

基于江苏省高速公路交通流量数据,构建高速公路全年流量模型,利用社会网络分析方法探究各县域的中心性与凝聚子群,结合地理探测器方法从江苏省整体以及苏南、苏中、苏北不同地域范围进行影响因素分析。结果表明:1)从总体上看,全年总流出量和流入量空间分布呈现由苏南向苏北递减的趋势;外出率较高地区分布于苏南—苏中—苏北地区的交界处、全省的边界地区以及苏南地区镇江市和常州市的交界地区;2)以苏州、南京、无锡为核心的苏南地区对全省有较强的交通集聚辐射效应,凝聚子群显示江苏省高速公路网络整体上呈现出“4组团、8片区”的特征;3)探测因子结果显示在省域范围内经济水平、产业结构、汽车保有量、人口规模、基础设施、居民购买力对高速公路流量的影响都较为显著,基于不同区域范围的因子决定力存在差异。

大流量高速公路养护安全施工交通组织实践探讨

随着近几年来高速公路的飞速建设和发展以及高速公路交通流量的迅猛增加,导致高速公路上通行车辆的流量越来越大,也显著增加了高速公路上的交通事故。同时,也因为高速公路的流量越来越大,导致高速公路养护安全施工的管理形式显得愈加严峻,据悉,大流量高速公路养护安全施工受到的影响非常之多,比如车速过快、驾驶员技术水平以及车辆自身机械因素和天气等多方面的影响因素。为了保障大流量高速公路养护施工安全进行,本文对大流量高速公路养护安全施工交通组织的实践进行探讨和分析。

探讨大流量高速公路养护安全施工的交通组织实践

目的：研究大流量高速公路养护安全施工的交通组织。方法 ：结合高速公路养护施工安全特征，制定确保大流量高速公路养护施工安全交通组织的实践路径。结果 ：高速公路养护施工可确保车辆安全通行。结论 ：大流量高速公路养护安全施工的交通组织保障路径具有一定的可行性。

高速公路入口匝道的模糊逻辑控制初探

目前,模糊控制在高速公路中已经开始应用,并取得了一定的成就,模糊控制在交通控制中有着广阔的发展前景。本文在分析公路匝道控制基础上,介绍了模糊控制方法及其参数的选取,给出了模糊控制系统设计步骤,在此基础上建立了入口匝道模糊控制器的设计机仿真实验,结果表明入口匝道控制其取得了预期效果。

广东:安全畅行高速 “一快二防三护”

为全力保障辖区道路安全形势持续平稳,全面做好道路交通事故预防与疫情防控工作,广东交通集团所属汕梅高速通过科学规划,运用“一快二防三护”措施,为40天的2021年春运顺利落幕提供了坚实保障。“一快”保障轻微事故快处快赔考虑到春运期间高速公路流量增加,为避免因轻微碰撞事故而造成道路拥堵。

基于BP神经网络的福泉高速公路车流量预测

高速公路车流量预测为高速公路管理企业对减轻高速公路的拥堵情况、改善高速公路的通行能力等方面提供了不可或缺的数据基础,也对其未来收益提供了参考。论文以福泉高速公路为研究对象,选择BP神经网络进行预测;其次分析车流量预测的影响因素,确定神经网络的输入和输出变量的数据类型、确定BP神经网络的层数及各层神经元的数量、各参数值,利用MATLAB构建完整的BP神经网络预测模型,最后收集样本数据,进行数据的预处理,利用样本数据对神经网络进行训练,包括训练完成后输入已知数据,进行实时预测,通过MATLAB进行仿真,证实方法可行有效,得到的结果证明BP神经网络的结构和参数值都是比较合理的,可以较好模拟现实环境,进行比较准确的预测。

Case History of the Disastrous Debris Flows of Tianmo Watershed in Bomi County, Tibet, China: Some Mitigation Suggestions

Debris flows and landslides, extensively developing and frequently occurring along Parlung Zangbo, seriously damage the Highway from Sichuan to Tiebt(G318) at Bomi County. The disastrous debris flows of the Tianmo Watershed on Sept. 4, 2007, July 25, 2010 and Sept. 4, 2010, blocked Parlung Zangbo River and produced dammed lakes, whose outburst flow made 50 m high terrace collapse at the opposite bank due to intense scouring on the foot of the terrace. As a result, the traffic was interrupted for 16 days in 2010 because that 900 m highway base was destructed and 430 m ruined. These debris flows were initiated by the glacial melting which was induced by continuous higher temperature and the following intensive rainfall, and expanded by moraines along channels and then blocked Parlung Zangbo. At the outlet of watershed,the density, velocity and peak discharge of debris flow was 2.06 t/m3, 12.7 m/s and 3334 m3/s, respectively. When the discharge at the outlet and the deposition volume into river exceeds 2125 m3/s and 126×103 m3, respectively, debris flow will completely blocked Parlung Zangbo. Moreover,if the shear stress of river flow on the foot of terrace and the inclination angel of terrace overruns 0. 377 N/m2 and 26°, respectively, the unconsolidated terrace will be eroded by outburst flow and collapse. It was strongly recommended for mitigation that identify and evade disastrous debris flows, reduce the junction angel of channels between river and watershed, build protecting wall for highway base and keep appropriate distance between highway and the edge of unconsolidated terrace.

Traffic Flow States in a Freeway with Bottleneck

The system of mixture of single lane and double lane is studied by a cellular automata model, which is developed by us based on the Nagel and Schreckenberg＇s models. We justify that the model can reach a stable states quickly. The density distributions of the stable state is presented for several cases, which illustrate the manner of the congestion. The relationship between the outflow rate and the total number of vehicles and that between the outflow rate and the density just before the bottleneck are both given. Comparing with the relationship that occurring in the granular flow, we conclude that the transition from the free traffic flow to the congested traffic flow can also be attributed to the abrupt variation through unstable flow state, which can naturally explain the discontinuities and the complex time variation behavior observed in the traffic flow experiments.

A New Macro Model for Traffic Flow on a Highway with Bus Stop

Based on the difference between the online bus stop and the offline bus stop, two macro models are developed to describe the two types of bus stops. The numerical results show that the two models can qualitatively reproduce some complex phenomena resulted by the two types of bus stops and that the otttine bus stop is more effective than the online bus stop when the initial density is relatively low.

Highway Green Open Area Planning Based on Annual Average Daily Vehicle Traffic

The development of a territory always followed by population growth and increasing the life necessities of the society. This condition makes increasing transportation activity that causes environmental pollution. Pollutants that are released by vehicle such as CO （carbon monoxide）, SO2 （sulfur oxides）, NO, （nitrogen oxides） are very harmful for public health. Indonesia is a country which has the high level of air pollution from transportation. One way to deal with the air pollution is to build green area （Ruang Terbuka Hijau） around the highway. Planning of open green area must be done comprehensively. There is an appropriate way to plan green area on the road by counting the number of AADV （annual average daily vehicles） （Lalu lintas harian rata rata） and estimated the amount of pollutantt that produced by vehicles. Calculation against the ability of plants in reducing pollutants and reached a unique relation between quantities of AADV by the number of plants that are necessary for reducing pollutants resulted by the traffic. The selection of plantation based on the shape of the tree canopy that provides the capacity of a pollutants reduction. After calculations the surface area of the tree leaves, the design of green area for highway can be reached so created an environmentally friendly and safe highway.

Traffic Flow Model Based on Power Flow

The article is research on the traffic situations of freeways. Different rules make different traffic situations. It is meaningful to research on traffic situations under different conditions. The author analyzes factors like traffic flow and safety, peflbrmance respectively, and proposes the theor3, basis for making more reasonable rules. The author first establishes evaluation system of traffic safety. Then, we compare the freeway network to power network to find a solution. and establish a traffic flow model based on power flow （TFPF）. It calculates power flow. So it applies the formula mode back to the traffic network, chalking up the perforumnce of the traffic condition. We utilize cellular automata （CA） method to simulate traffic circulation, and verify the accuracy of above model with the obtained data.

Dependence patterns associated with the fundamental diagram:a copula function approach

Randomness plays a major role in the interpretation of many interesting traffic flow phenomena,such as hysteresis,capacity drop and spontaneous breakdown. The analysis of the uncertainty and reliability of traffic systems is directly associated with their random characteristics. Therefore,it is beneficial to understand the distributional properties of traffic variables. This paper focuses on the dependence relation between traffic flow density and traffic speed,which constitute the fundamental diagram (FD). The traditional model of the FD is obtained essentially through curve fitting. We use the copula function as the basic toolkit and provide a novel approach for identifying the distributional patterns associated with the FD. In particular,we construct a rule-of-thumb nonparametric copula function,which in general avoids the mis-specification risk of parametric approaches and is more efficient in practice. By applying our construction to loop detector data on a freeway,we identify the dependence patterns existing in traffic data. We find that similar modes exist among traffic states of low,moderate or high traffic densities. Our findings also suggest that highway traffic speed and traffic flow density as a bivariate distribution is skewed and highly heterogeneous.