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Book Modeling of Traffic induced Emissions in the BCD Area

Download or read book Modeling of Traffic induced Emissions in the BCD Area written by Hayssam Hicham Sbayti and published by . This book was released on 2000 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increased urbanization of the Greater Beirut Area (GBA) over the past years has led to severe traffic congestion due to a deficient transportation system and significant reliance on the private vehicles as the primary passenger transport mode. As a result, air quality is continuously deteriorating particularly in densely populated areas. Beirut Central District (BCD), the center of economic growth in the GBA, is expected to witness severe air quality impacts in the medium- and long-term future. Hence, there is a growing need to couple the efficiency of transport activities with good air quality since both factors affect the welfare of the residents.--Historically, policy planners have focused on long-term strategies to abate elevated air pollution levels. For this purpose, traffic models and emission-dispersion models have been applied separately. The present research aims at integrating a traffic model and an emission-dispersion model to fit into the BCD context. The model will serve as a decision support tool for environmental officials and transportation policy planners for the management of traffic-related air pollution problems.--Four traffic management alternatives and five emission reduction strategies were studied for their effect on air quality. Total emissions and exposure levels in the peak period are evaluated. Implementation issues as well as a framework for the selection of best emission reduction options are proposed. Suggestions and recommendation for future work are also included at the end of the thesis.

Book Air Pollution Modelling and Simulation

Download or read book Air Pollution Modelling and Simulation written by Bruno Sportisse and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book collates the written contributions of the Second Conference on Air Pollution Modelling and Simulation (APMS 2001). A wide range of current topics is covered, focusing on three challenging issues: (1) the modelling issue of complex, multiphase, atmospheric chemistry; (2) the numerical issue associated with comprehensive three-dimensional chemistry-transport models; and (3) the key issues of data assimilation and inverse modelling. State-of-the art research is presented with many operational procedures applied at either forecast agencies or companies.

Book Emission estimation based on traffic models and measurements

Download or read book Emission estimation based on traffic models and measurements written by Nikolaos Tsanakas and published by Linköping University Electronic Press. This book was released on 2019-04-24 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traffic congestion increases travel times, but also results in higher energy usage and vehicular emissions. To evaluate the impact of traffic emissions on environment and human health, the accurate estimation of their rates and location is required. Traffic emission models can be used for estimating emissions, providing emission factors in grams per vehicle and kilometre. Emission factors are defined for specific traffic situations, and traffic data is necessary in order to determine these traffic situations along a traffic network. The required traffic data, which consists of average speed and flow, can be obtained either from traffic models or sensor measurements. In large urban areas, the collection of cross-sectional data from stationary sensors is a costefficient method of deriving traffic data for emission modelling. However, the traditional approaches of extrapolating this data in time and space may not accurately capture the variations of the traffic variables when congestion is high, affecting the emission estimation. Static transportation planning models, commonly used for the evaluation of infrastructure investments and policy changes, constitute an alternative efficient method of estimating the traffic data. Nevertheless, their static nature may result in an inaccurate estimation of dynamic traffic variables, such as the location of congestion, having a direct impact on emission estimation. Congestion is strongly correlated with increased emission rates, and since emissions have location specific effects, the location of congestion becomes a crucial aspect. Therefore, the derivation of traffic data for emission modelling usually relies on the simplified, traditional approaches. The aim of this thesis is to identify, quantify and finally reduce the potential errors that these traditional approaches introduce in an emission estimation analysis. According to our main findings, traditional approaches may be sufficient for analysing pollutants with global effects such as CO2, or for large-scale emission modelling applications such as emission inventories. However, for more temporally and spatially sensitive applications, such as dispersion and exposure modelling, a more detailed approach is needed. In case of cross-sectional measurements, we suggest and evaluate the use of a more detailed, but computationally more expensive, data extrapolation approach. Additionally, considering the inabilities of static models, we propose and evaluate the post-processing of their results, by applying quasi-dynamic network loading.

Book Modal Emissions Modeling with Real Traffic Data

Download or read book Modal Emissions Modeling with Real Traffic Data written by Jason A. Crawford and published by . This book was released on 1999 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report details the use of a modal emissions model to estimate the relative emissions of CO due to changes in vehicle operating characteristics on urban roadways. The Davis Institute for Transportation Studies Emissions Model (DITSEM) was selected to demonstrate the emissions characteristics of different freeway operating conditions. Instrumented vehicle data collected in Houston, Texas provides a set of operating parameters for which CO emissions are estimated. These estimates are calculated for different times of the day on the same facility to determine the relative emissions levels from a representative vehicle traveling on the freeway. The research team examined 10 samples along three roadways (two freeways, and one arterial). Implausible results were found in data exhibiting high average speeds (>60 mph) where average emissions rates were higher than those on the same roadway under congested conditions. This led to several conclusions of which the most important was that the DITSEM model not be used with samples where the percent of the driving cycle greater than 60 mph 2/sec exceeds 9%. This limit represents the highest value from which the model was derived for this variable. In addition, it is noted that the speed instrumentation was not able to provide sufficient precision for meaningful analysis with the available data.

Book Modeling Mobile Source Emissions

Download or read book Modeling Mobile Source Emissions written by National Research Council and published by National Academies Press. This book was released on 2000-07-28 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mobile Source Emissions Factor (MOBILE) model is a computer model developed by the U.S. Environmental Protection Agency (EPA) for estimating emissions from on-road motor vehicles. MOBILE is used in air-quality planning and regulation for estimating emissions of carbon monoxide (CO), volatile organic compounds (VOCs), and nitrogen oxides (NOx) and for predicting the effects of emissions-reduction programs.1 Because of its important role in air-quality management, the accuracy of MOBILE is critical. Possible consequences of inaccurately characterizing motor-vehicle emissions include the implementation of insufficient controls that endanger the environment and public health or the implementation of ineffective policies that impose excessive control costs. Billions of dollars per year in transportation funding are linked to air-quality attainment plans, which rely on estimates of mobile-source emissions. Transportation infrastructure decisions are also affected by emissions estimates from MOBILE. In response to a request from Congress, the National Research Council established the Committee to Review EPA's Mobile Source Emissions Factor (MOBILE) Model in October 1998. The committee was charged to evaluate MOBILE and to develop recommendations for improving the model.

Book Modeling Urban Transportation Emissions and Energy Use

Download or read book Modeling Urban Transportation Emissions and Energy Use written by and published by . This book was released on 1995 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Investigating the Effects of Traffic Calming on Near Road Air Quality Using Traffic Emissions and Air Dispersion Modelling

Download or read book Investigating the Effects of Traffic Calming on Near Road Air Quality Using Traffic Emissions and Air Dispersion Modelling written by Golnaz Ghafghazi and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "This thesis focuses on the development of a microscopic traffic simulation, emission and dispersion modeling system which aims at quantifying the effects of different types of traffic calming measures on vehicle emissions both at a link-level and at a network-level and on air quality at a corridor level using a scenario analysis. The study area is set in Montréal, Canada where a traffic simulation model for a dense urban neighborhood is extended with capabilities for microscopic emission estimation and dispersion modeling. The results indicate that on average, isolated calming measures increase carbon dioxide (CO2), carbon monoxide (CO) and nitrogen oxide (NOx) emissions by 1.50%, 0.33% and 1.45%, respectively across the entire network. Area-wide schemes result in a percentage increase of 3.84% for CO2, 1.22% for CO, and 2.18% for NOx. Along specific corridors where traffic calming measures were simulated, increases in CO2 emissions of up to 83% are observed. These increases are mainly associated with a change in vehicle drive-cycles through increased accelerations and decelerations. The results for air quality modeling suggest on average NO2 levels increase between 0.1% and 10% with respect to the base case. A high positive correlation of 0.7 between segment emissions of NOx and concentrations of NO2 is observed. Also, the effects of wind speed and direction are investigated in this thesis. The results show that higher wind speeds decrease NO2 concentrations on both sides of the roadway while winds orthogonal to the road increase the difference between concentrations on the leeward and windward sides with the leeward side experiencing higher levels. The effect of different measures on traffic volumes is also investigated and moderate decreases in areas that have undergone traffic calming are observed. Finally, the results show that speed bumps result in higher emission levels and poorer near-roadway air quality than speed humps. " --

Book Overview of Emission and Traffic Models and Evaluation of Vehicle Simulation Tools

Download or read book Overview of Emission and Traffic Models and Evaluation of Vehicle Simulation Tools written by and published by . This book was released on 2013 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the main concerns regarding the road transport sector is the fact that it constitutes one of the main sources of air pollution, especially in urban areas, since the combustion of hydrocarbon fuels in vehicles produces several pollutants. The most common approach for the assessment of traffic-related emission factors is the exhaust gas measurement of vehicles on chassis dynamometers over various driving cycles. A rather favourable approach in order to reduce the number of experimental procedures and thereby the cost of such tests is the development and calibration of vehicle simulation tools and emission models which could be used for the accurate evaluation and quantification of vehicle emissions without the necessity of expensive experimental campaigns. Today, there are several tools for the estimation of traffic-related emissions. Such tools are essential in any European or global policy dealing with emission projections, air pollution or climate change issues.^This study presents a description of the current emission models (COPERT, EMFAC, etc.), traffic (AIMSUN, Vissim, etc.) and vehicle simulation tools (ADVISOR, AUTONOMIE, PH EM etc.). The review of existing models and methods provides evidence that there is a large variety of available tools to calculate traffic-related emissions and to develop road transport emission inventories, however, new trends and policies must also be fully incorporated in the existing tools. In addition, in order to use emission models and vehicle simulation tools in the proper way, detailed and precise measurements of vehicle operation are required, otherwise any potential benefits may be lost. This is likely to be rather difficult since such information is relatively expensive or difficult to collect. For example, certain input data may not be available, such as vehicle loading and gear-shift behaviour. The last point raises an important consideration regarding model complexity.^More complex models have the potential to provide more accurate predictions as they take into account more variables. However, they also require more detailed input data which may not be readily available to the model user.

Book Empirical Modeling of the Effects of Traffic Characteristics on Vehicle Emissions

Download or read book Empirical Modeling of the Effects of Traffic Characteristics on Vehicle Emissions written by Russell Hooper Dalton and published by . This book was released on 1999 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Modeling Transportation Emissions Using Radar Based Vehicle Detection Data

Download or read book Modeling Transportation Emissions Using Radar Based Vehicle Detection Data written by Lang Yu and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation introduces a new and novel methodology for estimating vehicle emissions at signalized intersections. Radar based vehicle detection systems, when placed at intersection approaches, is able to track vehicle operational characteristics at very high frequency, thus provides an ideal data source for emission estimation. By combining radar based vehicle detection data and MOVES project level analysis operating mode distribution approach, a real-time emission estimation system for signalized intersections is proposed. The Emission Computation Tool for Radar Data is developed to facilitate the automatic and continuous computation of operating mode distribution and emissions. The emission rates computed can also be integrated with existing air dispersion models in order to be used for air quality conformity and hot spot analysis. A case study is conducted to test the feasibility and validity of the proposed real-time emission estimation system. The results showed that the data collected should be used for computing a variety of parameters, including traffic volume, average speed, operating mode distribution, total emissions and emission rates for various pollutants. With emission rates, existing pollutant dispersion models such as AERMOD are applied, yielding pollutant concentrations at various locations, providing additional functionalities to the system. Evaluation results showed that the traffic volume and emission rates computed matches closely with AADT data and EPA's emission standards. Finally, an operating mode based macroscopic emission model is developed by using both empirical data from the case study as well as incorporating existing traffic flow dynamics model. This predictive model is based on estimating total time spent in each operating mode directly from traffic demand and other variables. Total time idling is modeled using kinematic wave theory and queuing theory, while others are modeled using empirical data. The validation results showed that the model is able to achieve a high degree of accuracy, within approximately 10 percent of emission results computed using the radar data. In conclusion, both the proposed real-time emission estimation system at signalized intersections and the emission model developed showed to yield highly accurate and detailed results, and are applicable in real world intersection locations.

Book Traffic and Greenhouse Gas Modeling in Future Land Use Development Scenarios of Skagit County

Download or read book Traffic and Greenhouse Gas Modeling in Future Land Use Development Scenarios of Skagit County written by Abraham A. Mooney and published by . This book was released on 2011 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy use and greenhouse gas emissions are on the forefront of planning policy in the world today. In the U.S., the transportation sector accounts for 50 percent of greenhouse gas (GHG) emissions, the most of any single sector. State and local levels of government have been very proactive in the mitigation of GHG, with Washington State as one of the leaders. Two state laws passed in 2008 mandate a reduction in GHG and vehicle miles traveled (VMT), a primary metric in measuring traffic. This research focuses on Skagit County, Washington, as we attempt to model and quantify both GHG and VMT as they are affected by land use development. This research relies heavily on the Envision software platform as it was used a project involving an agent based model of alternative future landscapes. The project provided spatial population and employment data in the context of various future development scenarios such as the compact development of the Ecosystem Scenario where the goal was 90% growth within urban growth areas. On the other extreme was the Development Scenario where up to 40% of the growth was allowed in remote and non-incorporated areas. A majority of the research of this thesis document is devoted to the development of a traffic model structured around the commute of 17 population centers to job centers within Skagit County. The population centers are defined by traffic area zones, or TAZ, that encompass the entire county. The model is unique in traffic modeling literature for its small number of population and destination centers. The countywide accuracy of the model is exemplary at -0.87% standard error relative to current Highway Performance Monitoring System VMT data, although it should be understood that this result has not been repeated by applying the same methodology to other counties. Given that buildings energy use is second to the transportation sector as the largest single contributor to GHG emissions, a residential building model was created, in which parcel level population densities characterize high and low density building development. Defined as Apartments and Houses, respectively, within the text, energy use values were assigned to each from climate-specific data of the Residential Energy Consumption Survey national data set. Thus, as population and employment grow in various development scenarios of the Envision-Skagit 2060 project, the GHG generation from buildings and vehicles is calculated for comparison. The compact development of the Ecosystem Scenario generated the least amount of GHG in both models. Only a 5.9% difference was found in GHGs generated from the building model in the two extreme growth scenarios (Ecosystem and Development). In the traffic model, a 19% difference was found in the VMT of the same two scenarios. Compact, near job center development creates more of an impact on GHG inventory in the transportation sector at approximately twice the GHG impact of compact buildings. Comparing our results to Washington State law mandated reductions for both VMT and GHGs, we find that neither will be met in the transportation or building sectors. When a applying the Energy Information Association's most efficient vehicle fuel efficiency scenario where all vehicles are projected to average 59.6 mpg we find that even the best combination of scenarios (Ecosystem land-use and 59.3 mpg vehicle efficiency) results in GHGs that are 1.8 times larger than those permissible by the law as applied to year 2050. Our results assume the same 'standard of living' as today applied to home appliances, heating/cooling, and vehicle use. The traffic model assumes all commuters continue to use all modes of transit in the same fractions as today: 77.4% use single occupancy vehicles, 12.6% use high occupancy vehicles, 1.0% mass transit, 4.6% walk or bike, and 4.4% work at home in Skagit County. Although increased use of mass transportation was not modeled in this research, it may be the only option given our findings, with regards to the Washington State reduction requirements. In any case, our most important result is a novel approach to traffic modeling that requires only spatial knowedge of population and employment in order to predict traffic and quantify GHG emissions as they change with urban form.

Book A Modeling Framework for Estimating Emissions in Large Urban Areas

Download or read book A Modeling Framework for Estimating Emissions in Large Urban Areas written by Alexander Skabardonis and published by . This book was released on 1997 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: