交通道路型绿道理念的规划设计初探

从分析交通道路型绿道的概念、组成要素及功能出发,结合景观三元论,提出交通道路型绿道的规划设计理论,并对规划策略进行了详细阐述。以舟山市329国道沿线景观提升为例,通过分析其规划设计理念、目标定位等内容,提出具体的规划实施策略。

分析交通道路型绿道设计的规划

针对交通道路型绿道,在简述其组成、功能和意义的基础上,对其规划设计进行深入分析,提出规划设计理论和方法,旨在为实际的规划设计工作提供可靠参考依据,保证交通道路型绿道质量。

交通与运输概念及其系统辨析

鉴于交通与运输是交通运输领域内两个使用频率较高的词汇,实际使用时并未作严格区分。首先从基本概念和系统角度对交通与运输进行区分,而后讨论区分两者对道路运输发展的重要作用,分析认为,道路可以分为以发挥交通功能为主的交通型道路和以发挥运输功能为主的运输型道路,应该在确定道路类型的基础上进行道路建设和相关设施的配置,从而更好地发挥道路运输的功能。

针对我国北方地区热熔型道路交通标线的相关问题探讨研究

目前随着国家对于道路基础建设的投资力度不断增加,新改建道路的增加随之带来的是交通安全标线的大规模使用,对于目前具有特殊优势的热熔型道路交通标线,以其施工简单,性价比高,耐磨损的特点,大范围的利用在道路上。据调查,我国目前热熔型道路标线占到总标线里程的80%,但是目前热熔型道路交通标线涂料质量参差不齐,加之施工队伍的专业性知识比较薄弱,在大范围使用的同时,标线的常见病害弊端也逐渐显示了出来。而对于北方地区的热熔型道路交通标线,因为所处地区的气候条件恶劣,气温低风沙大,冰雪严重,所以较其他地方相比,北方地区的热熔型标线又凸显出更多的问题。针对于此类问题的研究,具有重大现实意义。本文将从热熔型道路交通标线的组成成分改良,施工特点,检测办法,多角度对热熔型道路交通标线常出现的问题进行原因探讨,从原因出发,针对标线柔韧度差的问题上,提出建议加入烯类物质,针对标线使用主要集中在北部温度较低地区,建议施工过程中加入防冻液助剂等物质,随后又从施工工艺的要点上,提出某些注意事项,人员配置上提出了新的较高的专业性要求。本篇论文也将为北方热熔型道路交通标线的理论体系的完善做一份参考。

Modeling for Action of Recovering from Erroneous Driving Condition Based on Revised Decision Tree

Driving behavior modeling is very important in the research area of road traffic systems safety analysis. The characteristics of action of recovering from erroneous driving condition underlying road traffic accident or incident scenarios is quantitatively analyzed, the model of action of recovering from erroneous driving condition is set up according to the identification of erroneous driving condition and the measurement of correction from erroneous driving condition. And then, the probability of action of recovering from erroneous driving condition has been measured based on a revised decision tree. The measure process uses a combination of test data and subjective judgments of driving behavior. It can provide a very helpful theoretical basis for the further analysis of driving behavior in road traffic system.

Relationship Between Urban Road Traffic Characteristics and Road Grade Based on a Time Series Clustering Model： A Case Study in Nanjing, China

With the increasing number of vehicles in large-and medium-sized cities challenges in urban traffic management, control, and road planning are being faced. Taxi GPS trajectory data is a novel data source that can be used to study the potential dynamic traffic characteristics of urban roads, and thus identify locations that show a notable lack of road planning. Considering that road traffic characteristics on their own are insufficient for a comprehensive understanding of urban traffic, we develop a road traffic characteristic time series clustering model to analyze the relationship between urban road traffic characteristics and road grade based on existing taxi trajectory data. We select the main urban area of Nanjing as our study area and use the taxi trajectory data of a single month for evaluating our method. The experiments show that the clustering model exhibit good performance and can be successfully used for road traffic characteristic classification. Moreover, we analyze the correlation between traffic characteristics and road grade to identify road segments with planning designs that do not match the actual traffic demands.

Vehicle emissions calculation for urban roads based on the Macroscopic Fundamental Diagram method and real-time traffic information

Vehicle emissions calculation methods mostly use ownership information or annual road monitoring data as the activity level to calculate air pollutant emissions,but it is hard to reflect either the emissions intensity under different conditions or the spatiotemporal characteristics in various sections based on such approaches.This paper presents a method based on the Macroscopic Fundamental Diagram and real-time traffic data to calculate vehicle emissions,which could reflect the operation conditions and emission characteristics of vehicles.Following the‘Technical Guide for the Compiling of Road Vehicle Air Pollutant Emissions Inventories’,the emissions of three roads with different lane numbers and road grades in Beijing were estimated and verified using this method.Compared with monitoring data,the average deviations of the traffic flow on the Fifth Expressway,Jingfu National Highway,and Jingzhou Provincial Highway were?25.5%,?26.5%,and?13.4%,respectively,and the average deviations of nitrogen oxides emissions were?27.7%,?12.9%,and?12%,respectively.This method showed good application potentials to construct the emissions inventory applied to the block-scale model and analyze the spatiotemporal distribution characteristics of motor vehicle emissions in urban areas.

A New Macro Model for Traffic Flow on a Highway with Ramps and Numerical Tests

In this paper, we present a new macro model for traffic flow on a highway with ramps based on the existing models. We use the new model to study the effects of on-off-ramp on the main road traffic during the morning rush period and the evening rush period. Numerical tests show that, during the two rush periods, these effects are often different and related to the status of the main road traffic. If the main road traffic flow is uniform, then ramps always produce stop-and-go traffic when the main road density is between two critical values, and ramps have little effect on the main road traffic when the main road density is less than the smaller critical value or greater than the larger critical value. If a small perturbation appears on the main road, ramp may lead to stop-and-go traffic, or relieve or even eliminate the stop-and-go traffic, under different circumstances. These results are consistent with real traffic, which shows that the new model is reasonable.

A novel conditional cell transmission model for oversaturated arterials

The objective of this work is to develop a novel feature for traffic flow models, when traffic queues on two-way arterials periodically extend until then they block an upstream signal in oversaturated conditions. The new model, proposed as conditional cell transmission model （CCTM） has been developed with two improvements. First, cell transmission model （CTM） is expanded for two-way arterials by taking account of all diverging and merging activities at intersections. Second, a conditional cell is added to simulate periodic spillback and blockages at an intersection. The results of experiments for a multilane, two-way, three-signal sample network demonstrate that CCTM can accommodate various traffic demands and accurate representation of blockages at intersections. The delay of left turns is underestimated by 40 % in moderate conditions and by 58% in oversamrated condition when using the CTM rather than CCTM. Finally, the consistency between HCS 2000 and CCTM shows that CCTM is a reliable methodology of modeling traffic flow in oversaturated condition.

Station Model for Rail Transit System Using Cellular Automata

In this paper, we propose a new cellular automata model to simulate the railway traffic at station. Based on NaSch model, the proposed station model is composed of the main track and the siding track. Two different schemes for trains passing through station are considered. One is the scheme of ＂pass by the main track, start and stop by the siding track＂. The other is the scheme of ＂two tracks play the same role＂. We simulate the train movement using the proposed model and analyze the traffic flow at station. The simulation results demonstrate that the proposed cellular automata model can be successfully used for the simulations of railway traffic. Some characteristic behaviors of railway traffic flow can be reproduced. Moreover, the simulation values of the minimum headway are close to the theoretical values. This result demonstrates the dependability and availability of the proposed model.

Restraint Usage Characteristics and Other Factors Associated with Safety of Children Involved in Motor Vehicle Crashes

Involvement in road traffic crashes as vehicle occupants is a leading cause of death and serious injury among children. The objective of this study was to investigate crash severity factors and child safety restraint use characteristics in order to identify effective countermeasures to increase children＇s highway safety. Characteristics and percentages of restraint use among child passengers aged 4-13 years were examined using highway crash data from Kansas. The association between restraint use, injury severity and characteristics of children involved in crashes were investigated using OR （odds ratios） and a logistic regression model, which was used to identify risk factors. Results showed that children, who were unrestrained, were seated in the front seat, traveling with drunk drivers and on rural roads, and traveling during nighttime was more vulnerable to severe injury in the case of motor vehicle crashes. The most frequent contributing causes related to crashes involving children included driver＇s inattention while driving, failure to yield right-of-way, driving too fast, wet roads and animals in the road. Based on identified critical factors, general countermeasure ideas to improve children＇s traffic safety were suggested, including age-appropriate and size-appropriate seat belt restraints and having children seated in the rear seat. Parents and children must gain better education regarding these safety measures in order to increase child safety on the road.

A New Lattice Model of Two-Lane Trafc Flow with the Consideration of the Honk Efect

In this paper, a new lattice model of two-lane traffic flow with the honk effect term is proposed to study the influence of the honk effect on wide moving jams under lane changing. The linear stability condition on two-lane highway is obtained by applying the linear stability theory. The modified Korteweg-de Vries （KdV） equation near the critical point is derived and the coexisting curves resulted from the modified KdV equation can be described, which shows that the critical point, the coexisting curve and the neutral stability line decrease with increasing the honk effect coe^cient. A wide moving jam can be conceivably described approximately in the unstable region. Numerical simulation is performed to verify the analytic results. The results show that the honk effect could suppress effectively the congested traffic patterns about wide moving jam propagation in lattice model of two-lane traffic flow.

Road traffic deaths in Kashan region, Iran： An eight-year study （2006-2013）

Purpose： The aim of this study was to analyze the trend of road traffic fatalities in Kashan Region, lran, in a period of eight years. Methods： Through a cross-sectional study, all road traffic deaths classified under the VO1-V99 codes according to ICD-10 in Kashan region, central Iran, from March 2006 to March 2013 and population data were collected from the registration system of Kashan University of Medical Sciences. Years of lost life （YLL） and mortality rates were calculated regarding age, gender and year of the accident. Generalized linear model （GLM） with Poisson log-linear link was used to evaluate the effects of the mentioned variables on mortality rate. Results： During the period of the study （8 years）, 928 people （767 men） died due to road traffic injuries （RTIs）. The total YLL was 20,818. The mortality rate due to RTIs has been declined constantly from 43.1 in March 2006 to 21.1 per 100,000 in March 2013. The highest mortality rate was found in the age group of over 60 years old and the lowest in the age group of 0-14 years old. Both mortality rate and YLL was greater in men than in women. Poisson regression showed that age, gender and year of the accidents had a significant effect on mortality rate （p 〈 0.001 ）. Conclusion： Although there has been a constant decline of mortality rate in Kashan area within the study period, the value remains higher than the mean level of Eastern Mediterranean region and the global average, which is a notable fact for policymakers and authorities.