Modal Emissions Modeling with Real Traffic Data

Modal Emissions Modeling with Real Traffic Data PDF Author: Jason A. Crawford
Publisher:
ISBN:
Category : Air
Languages : en
Pages : 84

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Book Description
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.

Modal Emissions Modeling with Real Traffic Data

Modal Emissions Modeling with Real Traffic Data PDF Author: Jason A. Crawford
Publisher:
ISBN:
Category : Air
Languages : en
Pages : 84

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Book Description
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.

Emission estimation based on traffic models and measurements

Emission estimation based on traffic models and measurements PDF Author: Nikolaos Tsanakas
Publisher: Linköping University Electronic Press
ISBN: 9176850927
Category :
Languages : en
Pages : 143

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Book Description
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.

Modeling Mobile-Source Emissions

Modeling Mobile-Source Emissions PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309070880
Category : Science
Languages : en
Pages : 257

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Book Description
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. 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.

Traffic Flow Dynamics

Traffic Flow Dynamics PDF Author: Martin Treiber
Publisher: Springer Science & Business Media
ISBN: 3642324592
Category : Science
Languages : en
Pages : 505

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Book Description
This textbook provides a comprehensive and instructive coverage of vehicular traffic flow dynamics and modeling. It makes this fascinating interdisciplinary topic, which to date was only documented in parts by specialized monographs, accessible to a broad readership. Numerous figures and problems with solutions help the reader to quickly understand and practice the presented concepts. This book is targeted at students of physics and traffic engineering and, more generally, also at students and professionals in computer science, mathematics, and interdisciplinary topics. It also offers material for project work in programming and simulation at college and university level. The main part, after presenting different categories of traffic data, is devoted to a mathematical description of the dynamics of traffic flow, covering macroscopic models which describe traffic in terms of density, as well as microscopic many-particle models in which each particle corresponds to a vehicle and its driver. Focus chapters on traffic instabilities and model calibration/validation present these topics in a novel and systematic way. Finally, the theoretical framework is shown at work in selected applications such as traffic-state and travel-time estimation, intelligent transportation systems, traffic operations management, and a detailed physics-based model for fuel consumption and emissions.

Black Carbon in the Environment

Black Carbon in the Environment PDF Author: Edward D. Goldberg
Publisher: Wiley-Interscience
ISBN:
Category : Environmental chemistry
Languages : en
Pages : 224

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Book Description
New York : J. Wiley, 1985.

A Review of Instantaneous Emission Models for Road Vehicles

A Review of Instantaneous Emission Models for Road Vehicles PDF Author: P. G. Boulter
Publisher:
ISBN: 9781846086700
Category : Automobiles
Languages : en
Pages : 55

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Book Description


Modeling Mobility with Open Data

Modeling Mobility with Open Data PDF Author: Michael Behrisch
Publisher: Springer
ISBN: 3319150243
Category : Technology & Engineering
Languages : en
Pages : 240

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Book Description
This contributed volume contains the conference proceedings of the Simulation of Urban Mobility (SUMO) conference 2014, Berlin. The included research papers cover a wide range of topics in traffic planning and simulation, including open data, vehicular communication, e-mobility, urban mobility, multimodal traffic as well as usage approaches. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

Air Pollution Modeling and its Application XXII

Air Pollution Modeling and its Application XXII PDF Author: Douw G. Steyn
Publisher: Springer
ISBN: 9400755775
Category : Science
Languages : en
Pages : 738

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Book Description
Recent developments in air pollution modeling and its application are explored here in contributions by researchers at the forefront of their field. The book is focused on local, urban, regional and intercontinental modeling; data assimilation and air quality forecasting; model assessment and evaluation; aerosol transformation; the relationship between air quality and human health and the interaction between climate change and air quality. The work will provide useful reference material for students and professors interested in air pollution modeling at the graduate level as well as researchers and professionals involved in developing and utilizing air pollution models.

ICSBE 2018

ICSBE 2018 PDF Author: Ranjith Dissanayake
Publisher: Springer
ISBN: 981139749X
Category : Architecture
Languages : en
Pages : 640

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Book Description
This book highlights current research and development in the area of sustainable built environments, currently one of the most important disciplines in civil engineering. It covers a range of topics, including sustainable construction and infrastructures, waste and wastewater management, enhanced sustainability, renewable and clean energy, sustainable materials and industrial ecology, building automation and virtual reality, and impact of climate change. As such it provides vital insights into responsible urbanization practices, and new tools and technologies in civil engineering that can mitigate the negative effects of the built environment.

Improving Transportation Data for Mobile Source Emission Estimates

Improving Transportation Data for Mobile Source Emission Estimates PDF Author: Arun Chatterjee
Publisher: Transportation Research Board
ISBN: 9780309060660
Category : Law
Languages : en
Pages : 140

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Book Description