Wang H.,Tsinghua University |
Fu L.,Tsinghua University |
Chen J.,Beijing Transportation Research Center
Journal of the Air and Waste Management Association | Year: 2010
A grid-based, bottom-up method has been proposed by combining a vehicle emission model and a travel demand model to develop a high-resolution vehicular emission inventory for Chinese cities. Beijing is used as a case study in which the focus is on fuel consumption and emissions from hot-stabilized activities of light-duty gasoline vehicles (LGVs) in 2005. The total quantity of emissions, emission intensity, and spatial distribution of emissions at 1- by 1-km resolution are presented and compared with results from other inventory methods commonly used in China. The results show that the total daily fuel consumption and vehicular emissions of carbon dioxide, carbon monoxide, hydrocarbons, and oxides of nitrogen from LGVs in the Beijing urban area in 2005 were 1.95 × 107 L, 4.28 × 104 t, 1.97 × 103 t, 0.28 × 103 t, and 0.14 × 103 t, respectively. Vehicular fuel consumption and emissions show spatial variations that are consistent with the traffic characteristics. The grid-based inventory developed in this study reflects the influence of traffic conditions on vehicle emissions at the microscale and may be applied to evaluate the effectiveness of trafficrelated measures on emission control in China. Copyright © 2010 Air & Waste Management Association. Source
Zhai Y.,Beijing Transportation Research Center
ICTIS 2013: Improving Multimodal Transportation Systems - Information, Safety, and Integration - Proceedings of the 2nd International Conference on Transportation Information and Safety | Year: 2013
Considerable errors exist in speed data that is obtained from various detectors, and its accuracy directly affects the results of various traffic analysis models. This research implemented 12 groups of field experiments on roads of different classes by using a test vehicle with GPS modules. It attempts to verify the accuracy discrepancy of travel speed data collected by a floating car system, microwave detectors, and loop detectors. Analysis shows that the average travel speed errors of floating cars on road sections of urban expressways and arteries are 13.6% and 27.8%, respectively, and the collected data and the actual speed have the same distribution. Compared with actual speed, the errors of the microwave detector on expressways and loop detectors on arteries are 30% and 56%, respectively. Although there exists a certain degree of error, basically, it can characterize the traffic conditions on the road section when the road section speed of the microwave detector is used to denote the travel speed. Study results provide suitable data sources for different traffic models that have different accuracy requirements. Besides, it provides a theoretical basis for improving data accuracy and completeness by using the redundant information of multi-source data. As the traffic congestion becoming increasingly serious, accurate and timely releasing of traffic information as well as reasonable traffic forecasts and guidance have gotten more and more attention. As one kind of the most important data of the Intelligent Transportation System, the accuracy of road section speed directly impacts the ITS application effect. Many kinds of detectors have been used for collecting road section speed, and the three most common are the floating car system, loop detectors, and microwave detectors. The floating car system can provide road section speed, but its accuracy has not been systematically validated. Currently, the literature (Jiang, Chang, Zhang 2009) just validated the accuracy of a single test vehicle by using different time intervals and upload times, but it wasn't for the whole system. Literature (Hu and Wen 2008) compared taxi speed and the travel speed of traffic flow by using the vehicle license plate method that theoretically obtained the precision of the floating car collection method, but it didn't involve the actual accuracy validation of the floating car collection system. Making the Beijing floating car collection system as the research object, by using a test vehicle, this research verified the accuracy of the system and analyzed the error distribution as well as the reasons affecting the data accuracy. © 2013 American Society of Civil Engineers. Source
Agency: Cordis | Branch: FP7 | Program: CP-SICA | Phase: SST.2008.3.1.6. | Award Amount: 6.03M | Year: 2009
The VIAJEO project will design, demonstrate and validate an open platform which will be able to: support the transport operations, planning and a wide range of traveller information services; deliver dynamic information independent from the language to improve their provision of transport information and traveller services through integrated traffic data collection and management; deliver a solution that enables cross-modal journey planning, dynamic route guidance, effective payment access and improved personal mobility, etc.; provide standardised interfaces to connect a variety of entities needed for the mobility services The open platform will facilitate the integration of components for data management allowing integration of European and local components as most convenient in Athens, Sao Paulo, Beijing and Shanghai. The demonstration cities in Europe, China and Brazil have been carefully chosen to ensure that they have a reputation as national role models, allowing the results of successful demonstrations to be extended to other cities in these countries and also potentially to other countries in the respective continents. The scientific and technical objectives of the project are: (1) Design of an open platform with interfaces to a wide range of mobility services (2) Implementation of the open platform in Europe, and in the emerging Economies, i.e. China and Brazil. (3) Validation of the open platform (4) Assessment of social and transport impacts of the implementation and demonstration of the open platform VIAJEO will involve users, traffic managers, public authorities, transport operators, equipment manufacturers, vehicle manufacturers, service providers, application and service developers, content owners and providers, and research organisations.
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: SST.2013.3-2. | Award Amount: 2.11M | Year: 2013
The goal of Viajeo PLUS is to benchmark outstanding solutions for innovative and green urban mobility in Europe, Latin America, China and Singapore and subsequently facilitate the uptake of these solutions across different cities in these regions, and Mediterranean Partner Countries (MPCs). Over a 36-month timeframe, the Viajeo PLUS consortium will engage with leading European innovative organisations and academic institutes and cooperate with cities across Europe, Latin America, China, Singapore and MPCs to facilitate the sharing of good practices and demonstration of innovative solutions. The Viajeo PLUS project will: Assess current mobility solutions and the potential uptake of different solutions for different scenarios. Through case studies, showcases and capacity building, it will gather key experts in mobility management, clean vehicle, public transport, infrastructure and city logistics, to develop executive plans for the implementation of existing solutions in a new and innovate way; Create a new web-based Virtual Best Solution book to facilitate wider uptake of solutions across more cities and regions; Organise four individual City Mobility Weeks in Europe, Latin America, China and Singapore respectively. A City Mobility Week consists of showcases, workshops and stakeholder meetings. Through interactive showcases, participants will benefit from gaining first-hand experience of innovative solutions. Participants will exchange knowledge, information and best practice experiences through various workshops and meetings; Organise fora in Istanbul to engage stakeholders in MPCs to lay the foundations for future inter-regional cooperation in research and development activities; Facilitate a twinning cities programme to allow representatives from cities to experience innovative solutions for future implementation. Together with SOLUTIONS, Viajeo PLUS will develop recommendations to the EC for future collaboration among cities and for research cooperation initiatives.
Zhou Y.,Tsinghua University |
Wu Y.,Tsinghua University |
Yang L.,Tsinghua University |
Fu L.,Tsinghua University |
And 5 more authors.
Atmospheric Environment | Year: 2010
Traffic congestion and air pollution were two major challenges for the planners of the 2008 Olympic Games in Beijing. The Beijing municipal government implemented a package of temporary transportation control measures during the event. In this paper, we report the results of a recent research project that investigated the effects of these measures on urban motor vehicle emissions in Beijing. Bottom-up methodology has been used to develop grid-based emission inventories with micro-scale vehicle activities and speed-dependent emission factors. The urban traffic emissions of volatile organic compounds (VOC), carbon monoxide (CO), nitrogen oxides (NOx) and particulate matter with an aerodynamic diameter of 10 μm or less (PM10) during the 2008 Olympics were reduced by 55.5%, 56.8%, 45.7% and 51.6%, respectively, as compared to the grid-based emission inventory before the Olympics. Emission intensity was derived from curbside air quality monitoring at the North 4th Ring Road site, located about 7 km from the National Stadium. Comparison between the emission intensity before and during the 2008 Olympics shows a reduction of 44.5% and 49.0% in daily CO and NOx emission from motor vehicles. The results suggest that reasonable traffic system improvement strategies along with vehicle technology improvements can contribute to controlling total motor vehicle emissions in Beijing after the Olympic Games. © 2009 Elsevier Ltd. All rights reserved. Source