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Sample records for measures vehicular emissions

  1. Impacts of temporary traffic control measures on vehicular emissions during the Asian games in Guangzhou, China.

    Science.gov (United States)

    Yao, Zhiliang; Zhang, Yingzhi; Shen, Xianbao; Wang, Xintong; Wu, Ye; He, Kebin

    2013-01-01

    To guarantee good traffic and air quality during the 16th Asian Games in Guangzhou, China, the government carried out two traffic control Drills before the Games and adopted traffic control measures during the Games. Vehicle activities before and during the first and second Drills, and during the Games, were surveyed. Based on the data under investigation, the impacts of control measures on traffic volumes and driving characteristics were analyzed during the first and second Drills, and the Games. The emission reduction of traffic control measures was also evaluated during the three stages using the MOBILE-China model. The results show that there were significant effects of implementing temporary traffic control measures on transportation activity and vehicular emissions. During the first and second Drills, and the Games, the average traffic volumes in monitored roads decreased, and the average speed of vehicles increased significantly The co-effects of traffic flow reduction, traffic congestion improvement, and the banning of high-emitting vehicles helped to greatly reduce the estimated emissions from motor vehicles in Guangzhou during the first and second Drills, and the Games. Estimated vehicular emissions were reduced by 38-52% during the first Drill and 28-36% for the second Drill. During the Asian Games, vehicular emissions of carbon monoxide (CO), hydrocarbon (HC), oxides of nitrogen (NO), and particulate matter with an aerodynamic diameter vehicular emissions of CO, HC, NOx, and PM10. Motor vehicles have become the most prevalent source of emissions and subsequently air pollution within Chinese cities. Understanding the impacts that different control measures have on vehicular emissions is very important in order to be able to control vehicle emissions. The results of this study will be very helpful for the further control of vehicle emissions in Guangzhou in the future. In addition, the effects of temporary transportation control measures will provide

  2. High contributions of vehicular emissions to ammonia in three European cities derived from mobile measurements

    Science.gov (United States)

    Elser, Miriam; El-Haddad, Imad; Maasikmets, Marek; Bozzetti, Carlo; Wolf, Robert; Ciarelli, Giancarlo; Slowik, Jay G.; Richter, Rene; Teinemaa, Erik; Hüglin, Christoph; Baltensperger, Urs; Prévôt, André S. H.

    2018-02-01

    Ambient ammonia (NH3) measurements were performed with a mobile platform in three European cities: Zurich (Switzerland), Tartu (Estonia) and Tallinn (Estonia) deploying an NH3 analyzer based on cavity ring-down spectroscopy. A heated inlet line along with an auxiliary flow was used to minimize NH3 adsorption onto the inlet walls. In addition, a detailed characterization of the response and recovery times of the measurement system was used to deconvolve the true NH3 signal from the remaining adsorption-induced hysteresis. Parallel measurements with an aerosol mass spectrometer were used to correct the observed NH3 for the contribution of ammonium nitrate, which completely evaporated in the heated line at the chosen temperature, in contrast to ammonium sulfate. In this way a quantitative measurement of ambient gaseous NH3 was achieved with sufficient time resolution to enable measurement of NH3 point sources with a mobile sampling platform. The NH3 analyzer and the aerosol mass spectrometer were complemented by an aethalometer and various gas-phase analyzers to enable a complete characterization of the sources of air pollution, including the spatial distributions and the regional background concentrations and urban increments of all measured components. Although at all three locations similar increment levels of organic aerosols were attributed to biomass burning and traffic, traffic emissions clearly dominated the city enhancements of NH3, equivalent black carbon (eBC) and carbon dioxide (CO2). Urban increments of 3.4, 1.8 and 3.0 ppb of NH3 were measured in the traffic areas in Zurich, Tartu and Tallinn, respectively, representing an enhancement of 36.6, 38.3 and 93.8% over the average background concentrations. Measurements in areas strongly influenced by traffic emissions (including tunnel drives) were used to estimate emission factors (EF) for the traffic-related pollutants. The obtained median EFs range between 136.8-415.1 mg kg-1 fuel for NH3, 157.1-734.8 mg

  3. Strategies to control vehicular emissions: Indian scenario

    Energy Technology Data Exchange (ETDEWEB)

    Virupaksha, T. [Central Institute of Road Transport, Pune (India)

    2002-07-01

    The paper presents a common urban transport policy framework to protect the local and global environment and a state-of-the-art review of recommendations and measures suggested by the local administration in Indian cities from time to time. The measures to combat pollution in urban areas is identified by different cities but there is no cohesive strategy for implementing them. The pursuit of some of these measures are that the haphazard and piecemeal measures have not helped to gain optimum benefit possible or to make a discernible impact on mobility demand and vehicular emissions. A more practical strategy is required to reduce both emission and congestion, using a mixed set of instruments. The instruments are taxes on fuels, vehicles, and parking, incentives and regulations affecting vehicle ownership, usage and movement, traffic management more importantly encouraging non-motorized transport like bicycles by providing suitable lanes. Some of the policy measures seriously needed to be implemented to reduce ongoing pollution menace are enforcing higher maintenance standards, introducing vehicles designed to meet stricter emission standards, retrofitting vehicles to use other kinds of clean fuel, reducing urban congestion through transport management measures, scrapping highly polluting and high usage vehicles, and strengthening institutional links and regulatory issues. 5 refs., 1 tab.

  4. Measurement of vehicle emissions and power performance of an engine dedicated to gasoline converted to natural gas vehicular

    Directory of Open Access Journals (Sweden)

    Flores-Meneses Oscar Febo

    2017-05-01

    Full Text Available The present research work reports the factorial experiment carried out in the Institute of Mechanical and Electromechanical Research (IIME of the Major Saint Andrew University (UMSA, the purpose was to evaluate vehicle power and emission of greenhouse gas carbon dioxide, as well as other gases with harmful effects on human health, carbon monoxide, nitrogen oxides and total hydrocarbons generated by an internal combustion engine dedicated to gasoline and converted to bi-fuel CNG. For experimentation, a test stand was assembled with a motor commonly used in light transport vehicles in the city of La Paz, and converted to CNG in two types of transformation technology, third and fifth generation, the first being subsidized by the Bolivian State. The results allowed to determine that emissions depend on the operating regime and that the vehicles converted to CNG do not significantly reduce the emission of GHG issued per unit time in relation to original operation with gasoline, this is because they generate higher emission gas flows in the same operating regimes. Emission of other gases harmful to health are significantly superior when converting to the engine with technology of 3rd generation without use of mixer. Being also its performance of lower power, it falls between 87 and 75% of the original value. It is evident that the type of technology and mode of conversion applied influences the emissions and vehicular power.

  5. Trends in vehicular emissions in China's mega cities from 1995 to 2005

    International Nuclear Information System (INIS)

    Wang Haikun; Fu Lixin; Zhou Yu; Du Xuan; Ge Weihua

    2010-01-01

    Multiyear inventories of vehicular emissions in Beijing, Shanghai and Guangzhou from 1995 through 2005 have been developed in this paper to study the vehicle emissions trends in China's mega cities during the past decade. The results show that the vehicular emissions of CO, HC, NO x and PM 10 have begun to slow their growth rates and perhaps even to decline in recent years due to the implementation of measures to control vehicular emissions in these cities. However, vehicular CO 2 emissions have substantially increased and still continue to grow due to little fuel economy improvement. Passenger cars and large vehicles (including heavy duty trucks and buses) are the major sources of vehicular CO 2 and CO emissions while large vehicles were responsible for nearly 70% and 80% of the vehicular NO x and PM 10 emissions in these mega cities. Motorcycles are also important contributors to vehicular emissions in Guangzhou and Shanghai. - The vehicular emissions (except CO 2 ) in China's mega cities have begun to slow their rates of growth and even to decline during the past decade.

  6. Temporal and spatial variation in recent vehicular emission inventories in China based on dynamic emission factors.

    Science.gov (United States)

    Cai, Hao; Xie, Shaodong

    2013-03-01

    The vehicular emission trend in China was tracked for the recent period 2006-2009 based on a database of dynamic emission factors of CO, nonmethane volatile organic compounds (NMVOC), NOx, PM10, CO2, CH4, and N2O for all categories of on-road motor vehicles in China, which was developed at the provincial level using the COPERT 4 model, to account for the effects of rapid advances in engine technologies, implementation of improved emission standards, emission deterioration due to mileage, and fuel quality improvement. Results show that growth rates of CO and NMVOC emissions slowed down, but NOx and PM10 emissions continued rising rapidly for the period 2006-2009. Moreover CO2, CH4, and N2O emissions in 2009 almost doubled compared to those in 2005. Characteristics of recent spatial distribution of emissions and emission contributions by vehicle category revealed that priority of vehicular emission control should be put on the eastern and southeastern coastal provinces and northern regions, and passenger cars and motorcycles require stricter control for the reduction of CO and NMVOC emissions, while effective reduction of NOx and PM10 emissions can be achieved by better control of heavy-duty vehicles, buses and coaches, and passenger cars. Explicit provincial-level Monte Carlo uncertainty analysis, which quantified for the first time the Chinese vehicular emission uncertainties associated with both COPERT-derived and domestically measured emission factors by vehicle technology, showed that CO, NMVOC, and NOx emissions for the period 2006-2009 were calculated with the least uncertainty, followed by PM10 and CO2, despite relatively larger uncertainties in N2O and CH4 emissions. The quantified low uncertainties of emissions revealed a necessity of applying vehicle technology- and vehicle age-specific dynamic emission factors for vehicular emission estimation, and these improved methodologies are applicable for routine update and forecast of China's on-road motor vehicle

  7. Impact Of Real-World Driving Characteristics On Vehicular Emissions

    OpenAIRE

    Nesamani, K S; Subramanian, K. P.

    2005-01-01

    With increase in traffic volume and change in travel related characteristics, vehicular emissions and energy consumption have increased significantly since two decades in India. Current models are not capable of estimating vehicular emissions accurately due to inadequate representation of real-world driving. The focus of this paper is to understand the level of Indian Driving cycle (IDC) in representing the real-world driving and to assess the impact of real-world driving on vehicular emissio...

  8. Decrease of VOC emissions from vehicular emissions in Hong Kong from 2003 to 2015: Results from a tunnel study

    Science.gov (United States)

    Cui, Long; Wang, Xiao Liang; Ho, Kin Fai; Gao, Yuan; Liu, Chang; Hang Ho, Steven Sai; Li, Hai Wei; Lee, Shun Cheng; Wang, Xin Ming; Jiang, Bo Qiong; Huang, Yu; Chow, Judith C.; Watson, John G.; Chen, Lung-Wen

    2018-03-01

    Vehicular emissions are one of major anthropogenic sources of ambient volatile organic compounds (VOCs) in Hong Kong. During the past twelve years, the government of the Hong Kong Special Administrative Region has undertaken a series of air pollution control measures to reduce vehicular emissions in Hong Kong. Vehicular emissions were characterized by repeated measurement in the same roadway tunnel in 2003 and 2015. The total net concentration of measured VOCs decreased by 44.7% from 2003 to 2015. The fleet-average VOC emission factor decreased from 107.1 ± 44.8 mg veh-1 km-1 in 2003 to 58.8 ± 50.7 mg veh-1 km-1 in 2015, and the total ozone (O3) formation potential of measured VOCs decreased from 474.1 mg O3 veh-1 km-1 to 190.8 mg O3 veh-1 km-1. The emission factor of ethene, which is one of the key tracers for diesel vehicular emissions, decreased by 67.3% from 2003 to 2015 as a result of the strict control measures on diesel vehicular emissions. Total road transport VOC emissions is estimated to be reduced by 40% as compared with 2010 by 2020, which will be an important contributor to achieve the goal of total VOC emission reduction in the Pearl River Delta region. The large decrease of VOC emissions from on-road vehicles demonstrates the effectiveness of past multi-vehicular emission control strategy in Hong Kong.

  9. Control strategies for vehicular NOx emissions in Guangzhou, China

    International Nuclear Information System (INIS)

    Shao Min; Zhang Yuanhang; Raufer, Roger

    2001-01-01

    Guangzhou is a city in southern China that has experienced very rapid economic development in recent years. The city's air has very high concentrations of various pollutants, including sulphur dioxide (SO 2 , oxides of nitrogen (NOx), ozone (O 3 ) and particulate. This paper reviews the changes in air quality in the city over the past 15 years, and notes that a serious vehicular-related emissions problem has been superimposed on the traditional coal-burning problem evident in most Chinese cities. As NOx concentrations have increased, oxidants and photochemical smog now interact with the traditional SO 2 and particulate pollutants, leading to increased health risks and other environmental concerns. Any responsible NOx control strategy for the city must include vehicle emission control measures. This paper reviews control strategies designed to abate vehicle emissions to fulfill the city's air quality improvement target in 2010. A cost-effectiveness analysis suggests that, while NOx emission control is expensive, vehicular emission standards could achieve a relatively sizable emissions reduction at reasonable cost. To achieve the 2010 air quality target of NOx, advanced implementation of EURO3 standards is recommended, substituting for the EURO2 currently envisioned in the national regulations Related technical options, including fuel quality improvements and inspection/maintenance (I/M) upgrades (ASM or IM240) are assessed as well. (author)

  10. Estimating Vehicular Emission in Kathmandu Valley, Nepal

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    Krishna Prasad Ghimire

    2014-12-01

    Full Text Available The study estimate, the vehicular emission load for CO, CO2 , HCs, NOX, SO2, Dioxin/Furans, Particulate Matters (PM10, PM2.5, Black carbon and Organic Carbon by using emission factors and Global Warming Potentials (GWPs of the pollutants (CO2, NOX, BC and OC. For this purpose, data were collected through the video tape record (in 30 sites, questionnaire survey, field visit, and literatures review. The total estimated emission of Kathmandu Valley (KV was 7231053.12 ton/year. Of the total emission, CO2 emission was highest i.e., 91.01% followed by CO 5.03%, HC 0.96%, NOX 0.60%, PM10 0.18% and SO2 0.10%. Annually 529353.36 μg Toxic Equivalent (TEQ of Dioxin/Furan produced and directly disperse to the ambient environment. The total estimated PM2.5, BC and OC emission were 9649.40 ton/year, 1640.4 ton/year and 2894.82 ton/year. The total carbon equivalence of the combined emissions (CO2, NOX and BC for 100-years standard time horizon is 10579763.6 ton CO2-eq i.e., 2885390.07 ton carbon.CO2 alone will be responsible, for about 62% of the impacts for the next century from current emissions of CO2, NOX and BC. Of the total emission Heavy Duty Vehicles (HDV emits 50%, Light Duty Vehicles (LDV emits, 27%, 2-Wheelers emits 22% and 3-Wheeler (Tempo emits 1%. The total emission of all pollutants combined per vehicle together was estimated to be 5.46 ton/year which was estimated as 23.63, 10.35, 1.83 and 5.58 ton/year for HDV, LDV, 2-Wheelers and 3-Wheeler respectively. DOI: http://dx.doi.org/10.3126/ije.v3i4.11742      International Journal of EnvironmentVolume-3, Issue-4, Sep-Nov 2014Page: 133-146 

  11. Strategies for controlling pollution from vehicular emissions in Beijing

    International Nuclear Information System (INIS)

    Wang, Qidong; He, Kebin; Li, Tiejun; Fu, Lixin

    2002-01-01

    The paper describes the severe situation of vehicular emission in Beijing and discusses the following mitigation strategies: Improving fuel quality, controlling the exhaust from new vehicles, controlling the emissions from vehicles in use through e.g. Inspection Maintenance (I/M), renovating in-use vehicles and scrapping of old vehicles and road infrastructure and traffic policies. (Author)

  12. Strategies for controlling pollution from vehicular emissions in Beijing

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qidong; He, Kebin; Li, Tiejun; Fu, Lixin

    2002-07-01

    The paper describes the severe situation of vehicular emission in Beijing and discusses the following mitigation strategies: Improving fuel quality, controlling the exhaust from new vehicles, controlling the emissions from vehicles in use through e.g. Inspection Maintenance (I/M), renovating in-use vehicles and scrapping of old vehicles and road infrastructure and traffic policies. (Author)

  13. Emission factor ratios, SOA mass yields, and the impact of vehicular emissions on SOA formation

    Science.gov (United States)

    Ensberg, J. J.; Hayes, P. L.; Jimenez, J. L.; Gilman, J. B.; Kuster, W. C.; de Gouw, J. A.; Holloway, J. S.; Gordon, T. D.; Jathar, S.; Robinson, A. L.; Seinfeld, J. H.

    2014-03-01

    The underprediction of ambient secondary organic aerosol (SOA) levels by current atmospheric models in urban areas is well established, yet the cause of this underprediction remains elusive. Likewise, the relative contribution of emissions from gasoline- and diesel-fueled vehicles to the formation of SOA is generally unresolved. We investigate the source of these two discrepancies using data from the 2010 CalNex experiment carried out in the Los Angeles Basin (Ryerson et al., 2013). Specifically, we use gas-phase organic mass (GPOM) and CO emission factors in conjunction with measured enhancements in oxygenated organic aerosol (OOA) relative to CO to quantify the significant lack of closure between expected and observed organic aerosol concentrations attributable to fossil-fuel emissions. Two possible conclusions emerge from the analysis to yield consistency with the ambient data: (1) vehicular emissions are not a dominant source of anthropogenic fossil SOA in the Los Angeles Basin, or (2) the ambient SOA mass yields used to determine the SOA formation potential of vehicular emissions are substantially higher than those derived from laboratory chamber studies.

  14. An updated emission inventory of vehicular VOCs and IVOCs in China

    Science.gov (United States)

    Liu, Huan; Man, Hanyang; Cui, Hongyang; Wang, Yanjun; Deng, Fanyuan; Wang, Yue; Yang, Xiaofan; Xiao, Qian; Zhang, Qiang; Ding, Yan; He, Kebin

    2017-10-01

    Currently, the emission inventory of vehicular volatile organic compounds (VOCs) is one of those with the largest errors and uncertainties due to suboptimal estimation methods and the lack of first-hand basic data. In this study, an updated speciated emission inventory of VOCs and an estimation of intermediate-volatility organic compounds (IVOCs) from vehicles in China at the provincial level for the year of 2015 are developed based on a set of state-of-the-art methods and an abundance of local measurement data. Activity data for light-duty vehicles are derived from trajectories of more than 70 000 cars for 1 year. The annual mileage of trucks are calculated from reported data by more than 2 million trucks in China. The emission profiles are updated using measurement data. Vehicular tailpipe emissions (VTEs) and four types of vehicular evaporation emissions (VEEs), including refueling, hot soak, diurnal and running loss, are taken into account. Results show that the total vehicular VOC emissions in China are 4.21 Tg (with a 95 % confidence interval range from 2.90 to 6.54 Tg) and the IVOC emissions are 200.37 Gg in 2015. VTEs are still the predominant contributor, while VEEs are responsible for 39.20 % of VOC emissions. The control of VEEs is yet to be optimized in China. Among VTEs, passenger vehicles emissions have the largest share (49.86 %), followed by trucks (28.15 %) and motorcycles (21.99 %). Among VEEs, running loss is the largest contributor (81.05 %). For both VTEs and VEEs, Guangdong, Shandong and Jiangsu province are three of the highest, with a respective contribution of 10.66, 8.85 and 6.54 % to the total amounts of VOCs from vehicles. 97 VOC species are analyzed in this VOC emission inventory. i-Pentane, toluene and formaldehyde are found to be the most abundant species in China's vehicular VOC emissions. The estimated IVOCs are another inconvenient truth, concluding that precursor emissions for secondary organic aerosol (SOA) from vehicles are much

  15. An updated emission inventory of vehicular VOCs and IVOCs in China

    Directory of Open Access Journals (Sweden)

    H. Liu

    2017-10-01

    Full Text Available Currently, the emission inventory of vehicular volatile organic compounds (VOCs is one of those with the largest errors and uncertainties due to suboptimal estimation methods and the lack of first-hand basic data. In this study, an updated speciated emission inventory of VOCs and an estimation of intermediate-volatility organic compounds (IVOCs from vehicles in China at the provincial level for the year of 2015 are developed based on a set of state-of-the-art methods and an abundance of local measurement data. Activity data for light-duty vehicles are derived from trajectories of more than 70 000 cars for 1 year. The annual mileage of trucks are calculated from reported data by more than 2 million trucks in China. The emission profiles are updated using measurement data. Vehicular tailpipe emissions (VTEs and four types of vehicular evaporation emissions (VEEs, including refueling, hot soak, diurnal and running loss, are taken into account. Results show that the total vehicular VOC emissions in China are 4.21 Tg (with a 95 % confidence interval range from 2.90 to 6.54 Tg and the IVOC emissions are 200.37 Gg in 2015. VTEs are still the predominant contributor, while VEEs are responsible for 39.20 % of VOC emissions. The control of VEEs is yet to be optimized in China. Among VTEs, passenger vehicles emissions have the largest share (49.86 %, followed by trucks (28.15 % and motorcycles (21.99 %. Among VEEs, running loss is the largest contributor (81.05 %. For both VTEs and VEEs, Guangdong, Shandong and Jiangsu province are three of the highest, with a respective contribution of 10.66, 8.85 and 6.54 % to the total amounts of VOCs from vehicles. 97 VOC species are analyzed in this VOC emission inventory. i-Pentane, toluene and formaldehyde are found to be the most abundant species in China's vehicular VOC emissions. The estimated IVOCs are another inconvenient truth, concluding that precursor emissions for secondary organic

  16. VOC from Vehicular Evaporation Emissions: Status and Control Strategy.

    Science.gov (United States)

    Liu, Huan; Man, Hanyang; Tschantz, Michael; Wu, Ye; He, Kebin; Hao, Jiming

    2015-12-15

    Vehicular evaporative emissions is an important source of volatile organic carbon (VOC), however, accurate estimation of emission amounts and scientific evaluation of control strategy for these emissions have been neglected outside of the United States. This study provides four kinds of basic emission factors: diurnal, hot soak, permeation, and refueling. Evaporative emissions from the Euro 4 vehicles (1.6 kg/year/car) are about four times those of U.S. vehicles (0.4 kg/year/car). Closing this emissions gap would have a larger impact than the progression from Euro 3 to Euro 6 tailpipe HC emission controls. Even in the first 24 h of parking, China's current reliance upon the European 24 h diurnal standard results in 508 g/vehicle/year emissions, higher than 32 g/vehicle/year from Tier 2 vehicles. The U.S. driving cycle matches Beijing real-world conditions much better on both typical trip length and average speed than current European driving cycles. At least two requirements should be added to the Chinese emissions standards: an onboard refueling vapor recovery to force the canister to be sized sufficiently large, and a 48-h evaporation test requirement to ensure that adequate purging occurs over a shorter drive sequence.

  17. Cognitive disorders in children associated with urban vehicular emissions.

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    Annavarapu, Ramesh Naidu; Kathi, Srujana

    2016-01-01

    This review introduces recent advances in an emerging research area that is focussed on studying the effect of exposure to vehicular emissions on cognition, with specific attention to children from urban environments. Today, air pollution is a global environmental issue, especially in urban environments, emitting particulate matter (PM), nitrogen dioxide (NO2), carbon monoxide (CO), volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) into the surroundings. The association of exposure to urban air pollution and cognitive disorders in children is a major cause of concern. We review recent findings associated with exposure to air pollutants and explained the potential mechanisms driving oxidative stress in living systems. An attempt has been made to investigate the cognitive effects of air pollutants leading to neurodegeneration, neurodysfunction, attention deficit/hypersensitivity deficiencies and autism in children. Accumulating evidence suggests that urban air pollution may have significant impact on central nervous system (CNS) of the developing brain. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Cognitive disorders in children associated with urban vehicular emissions

    International Nuclear Information System (INIS)

    Annavarapu, Ramesh Naidu; Kathi, Srujana

    2016-01-01

    This review introduces recent advances in an emerging research area that is focussed on studying the effect of exposure to vehicular emissions on cognition, with specific attention to children from urban environments. Today, air pollution is a global environmental issue, especially in urban environments, emitting particulate matter (PM), nitrogen dioxide (NO_2), carbon monoxide (CO), volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) into the surroundings. The association of exposure to urban air pollution and cognitive disorders in children is a major cause of concern. We review recent findings associated with exposure to air pollutants and explained the potential mechanisms driving oxidative stress in living systems. An attempt has been made to investigate the cognitive effects of air pollutants leading to neurodegeneration, neurodysfunction, attention deficit/hypersensitivity deficiencies and autism in children. Accumulating evidence suggests that urban air pollution may have significant impact on central nervous system (CNS) of the developing brain. - Highlights: • Developing brain is vulnerable to the effect of urban air pollution. • Urban emissions cause neurodegeneration and attention deficits among children. • Exposure to air pollutants leads to oxidative stress in living systems.

  19. Quantifying impacts on air quality of vehicular emissions in Sao Paulo and Rio de Janeiro

    Science.gov (United States)

    Artaxo, Paulo; Ferreira de Brito, Joel; Godoy, José Marcus; Luiza Godoy, Maria; Junior, Djacinto

    2016-04-01

    Vehicular emissions in megacities such as Sao Paulo and Rio de Janeiro are increasingly becoming a global issue. The São Paulo Metropolitan Area (SPMA), located in Southeast of Brazil, is a megacity with a population of 18 million people, with 7 million cars and large-scale industrial emissions. Rio de Janeiro is also a large city with different meteorology than São Paulo. All cars in Brazil runs gasohol, with 23% ethanol in gasoline, and for the last 10 years, flex cars that can run on gasohol, ethanol or any mixture dominate the market. Overall ethanol accounts for about 30-40% of fuel burned in both cities. To improve the understanding of vehicular emission impacts on aerosol composition and life cycle in these two large megacities a source apportionment study, combining online and offline measurements, was performed. Aerosols were collected for one year to capture seasonal variability at 4 sites in each city, with inorganic and organic aerosol component being sampled. Organic and elemental carbon were measured using a Sunset Laboratory Dual Optics (transmission and reflectance) Carbon Analyzer and about 22 trace elements has been measured using polarized X-Ray Fluorescence (XRF). Aerosol mass and black carbon were also measured, as well as trace gases to help in aerosol source apportionment. In Sao Paulo, the average PM2.5 mass concentration obtained varied from 9.6 to 12.2 μg m-3 for the several sites, and similar concentrations were measured in Rio de Janeiro. At all sites, organic matter (OM) has dominated fine mode aerosol concentration with 42 to 60% of the aerosol mass. EC accounted for 21 to 31% of fine mode aerosol mass concentration. Sulfate accounted for 21 to 26% of PM2.5 for the sites. Aerosol source apportionment was done with receptor analysis and integration with online data such as PTR-MS, Aethalometers, Nephelometers and ACSM helped to apportion vehicular emissions. For the 8 sites operated in Sao Paulo and Rio de Janeiro, vehicular

  20. Low Emissions and Delay Optimization for an Isolated Signalized Intersection Based on Vehicular Trajectories.

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    Ciyun Lin

    Full Text Available A traditional traffic signal control system is established based on vehicular delay, queue length, saturation and other indicators. However, due to the increasing severity of urban environmental pollution issues and the development of a resource-saving and environmentally friendly social philosophy, the development of low-carbon and energy-efficient urban transport is required. This paper first defines vehicular trajectories and the calculation of vehicular emissions based on VSP. Next, a regression analysis method is used to quantify the relationship between vehicular emissions and delay, and a traffic signal control model is established to reduce emissions and delay using the enumeration method combined with saturation constraints. Finally, one typical intersection of Changchun is selected to verify the model proposed in this paper; its performance efficiency is also compared using simulations in VISSIM. The results of this study show that the proposed model can significantly reduce vehicle delay and traffic emissions simultaneously.

  1. Low Emissions and Delay Optimization for an Isolated Signalized Intersection Based on Vehicular Trajectories.

    Science.gov (United States)

    Lin, Ciyun; Gong, Bowen; Qu, Xin

    2015-01-01

    A traditional traffic signal control system is established based on vehicular delay, queue length, saturation and other indicators. However, due to the increasing severity of urban environmental pollution issues and the development of a resource-saving and environmentally friendly social philosophy, the development of low-carbon and energy-efficient urban transport is required. This paper first defines vehicular trajectories and the calculation of vehicular emissions based on VSP. Next, a regression analysis method is used to quantify the relationship between vehicular emissions and delay, and a traffic signal control model is established to reduce emissions and delay using the enumeration method combined with saturation constraints. Finally, one typical intersection of Changchun is selected to verify the model proposed in this paper; its performance efficiency is also compared using simulations in VISSIM. The results of this study show that the proposed model can significantly reduce vehicle delay and traffic emissions simultaneously.

  2. Estimation of vehicular emissions using dynamic emission factors: A case study of Delhi, India

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    Mishra, Dhirendra; Goyal, P.

    2014-12-01

    The estimation of vehicular emissions depends mainly on the values of emission factors, which are used for the development of a comprehensive emission inventory of vehicles. In this study the variations of emission factors as well as the emission rates have been studied in Delhi. The implementation of compressed natural gas (CNG), in the diesel and petrol, public vehicles in the year 2001 has changed the complete air quality scenario of Delhi. The dynamic emission factors of criteria pollutants viz. carbon monoxide (CO), nitrogen oxide (NOx) and particulate matter (PM10) for all types of vehicles have been developed after, which are based on the several factors such as regulated emission limits, number of vehicle deterioration, vehicle increment, vehicle age etc. These emission factors are found to be decreased continuously throughout the study years 2003-2012. The International Vehicle Emissions (IVE) model is used to estimate the emissions of criteria pollutants by utilizing a dataset available from field observations at different traffic intersections in Delhi. Thus the vehicular emissions, based on dynamic emission factors have been estimated for the years 2003-2012, which are found to be comparable with the monitored concentrations at different locations in Delhi. It is noticed that the total emissions of CO, NOx, and PM10 are increased by 45.63%, 68.88% and 17.92%, respectively up to the year 2012 and the emissions of NOx and PM10 are grown continuously with an annual average growth rate of 5.4% and 1.7% respectively.

  3. Non-methane hydrocarbon characteristics of motor vehicular emissions in the Pearl River Delta region

    Science.gov (United States)

    Tsai, Wai Yan

    2007-12-01

    Air pollution problem in Hong Kong and the Pearl River Delta (PRD) region has raised much concern from the public in recent years. The primary aim of this research is to use field measurement data to characterize non-methane hydrocarbons (NMHCs) in emission from motor vehicles. Fuel vapor compositions for several commonly used vehicular fuels in Hong Kong, Macau, Guangzhou and Zhuhai were analyzed in 2003, and they are believed to be the first one reported for the PRD region. These profiles were used to study the impact of evaporative loss of the fuels on air quality. From the roadside and tunnel samples collected in the four cities mentioned above from 2000 to 2003, results showed that vehicular engine combustion was a main NMHC source, while gasoline evaporative losses also contributed much to the total NMHC emission, besides, LPG leakage was also found to be significant from the tunnel measurement data collected in Hong Kong. Characteristics of vehicular engine exhaust emissions were also studied. Measurements of diesel emission showed a large influence on the emission profile due to the change of diesel compositions. The E/E ratios implied that gasoline-powered vehicles in Hong Kong were equipped with well functioning catalysts, while those in Guangzhou and Zhuhai, especially the motorcycles, were found dirtier in NMHC emission. Although the E/E ratios showed that private cars in Hong Kong had high combustion efficiency, the existence of significant amounts of unburned gasoline in their exhaust stream pointed out that they still had low fuel economy. From the results of a simple model, it was found that the evaporative losses of gasoline and LPG contributed much to the total NMHC pollution from vehicle. The preliminary results from the dynamometer study conducted in Hong Kong showed large variations of exhaust characteristics for private cars and taxis during different driving speeds. The results can be used as scientific basis for regulatory parties in

  4. Formation of secondary organic aerosol coating on black carbon particles near vehicular emissions

    Science.gov (United States)

    Lee, Alex K. Y.; Chen, Chia-Li; Liu, Jun; Price, Derek J.; Betha, Raghu; Russell, Lynn M.; Zhang, Xiaolu; Cappa, Christopher D.

    2017-12-01

    Black carbon (BC) emitted from incomplete combustion can result in significant impacts on air quality and climate. Understanding the mixing state of ambient BC and the chemical characteristics of its associated coatings is particularly important to evaluate BC fate and environmental impacts. In this study, we investigate the formation of organic coatings on BC particles in an urban environment (Fontana, California) under hot and dry conditions using a soot-particle aerosol mass spectrometer (SP-AMS). The SP-AMS was operated in a configuration that can exclusively detect refractory BC (rBC) particles and their coatings. Using the -log(NOx / NOy) ratio as a proxy for photochemical age of air masses, substantial formation of secondary organic aerosol (SOA) coatings on rBC particles was observed due to active photochemistry in the afternoon, whereas primary organic aerosol (POA) components were strongly associated with rBC from fresh vehicular emissions in the morning rush hours. There is also evidence that cooking-related organic aerosols were externally mixed from rBC. Positive matrix factorization and elemental analysis illustrate that most of the observed SOA coatings were freshly formed, providing an opportunity to examine SOA coating formation on rBCs near vehicular emissions. Approximately 7-20 wt % of secondary organic and inorganic species were estimated to be internally mixed with rBC on average, implying that rBC is unlikely the major condensation sink of SOA in this study. Comparison of our results to a co-located standard high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) measurement suggests that at least a portion of SOA materials condensed on rBC surfaces were chemically different from oxygenated organic aerosol (OOA) particles that were externally mixed with rBC, although they could both be generated from local photochemistry.

  5. Integrating internet GPS vehicle tracking data into a bottom-up vehicular emissions inventory and atmospheric simulation in South-East, Brazil

    Science.gov (United States)

    Ibarra Espinosa, S.; Ynoue, R.; Giannotti, M., , Dr

    2017-12-01

    It has been shown the importance of emissions inventories for air quality studies and environmental planning at local, regional (REAS), hemispheric (CLRTAP) and global (IPCC) scales. It has been shown also that vehicules are becoming the most important sources in urban centers. Several efforts has been made in order to model vehicular emissions to obtain more accurate emission factors based on Vehicular Specific Power (VPS) with IVE and MOVES based on VSP, MOBILE, VERSIT and COPERT based on average speed, or ARTEMIS and HBEFA based on traffic situations. However, little effort has been made to improve traffic activity data. In this study we are proposing using a novel approach to develop vehicular emissions inventory including point data from MAPLINK a company that feeds with traffic data to Google. This includes working and transforming massive amount of data to generate traffic flow and speeds. The region of study is the south east of Brazil including São Paulo metropolitan areas. To estimate vehicular emissions we are using the open source model VEIN available at https://CRAN.R-project.org/package=vein. We generated hourly traffic between 2010-04-21 and 2010-10-22, totalizing 145 hours. This data consists GPS readings from vehicles with assurance policy, applications and other sources. This type data presents spacial bias meaning that only a part of the vehicles are tracked. We corrected this bias using the calculated speed as proxy of traffic flow using measurements of traffic flow and speed per lane made in São Paulo. Then we calibrated the total traffic estimating Fuel Consumption with VEIN and comparing Fuel Sales for the region. We estimated the hourly vehicular emissions and produced emission maps and data-bases. In addition, we simulated atmospheric simulations using WRF-Chem to identify which inventory produces better agreement with air pollutant observations. New technologies and big data provides opportunities to improve vehicular emissions

  6. Estimating emissions on vehicular traffic based on projected energy and transport demand on rural roads: Policies for reducing air pollutant emissions and energy consumption

    International Nuclear Information System (INIS)

    Ozan, Cenk; Haldenbilen, Soner; Ceylan, Halim

    2011-01-01

    This study deals with the estimation of emissions caused by vehicular traffic based on transport demand and energy consumption. Projected transport demand is calculated with Genetic Algorithm (GA) using population, gross domestic product per capita (GDPPC) and the number of vehicles. The energy consumption is modelled with the GA using the veh-km. The model age of the vehicles and their corresponding share for each year using the reference years is obtained. The pollutant emissions are calculated with estimated transport and energy demand. All the calculations are made in line to meet the European standards. For this purpose, two cases are composed. Case 1: Emissions based on energy consumption, and Case 2: Emissions based on transport demand. The both cases are compared. Three policies are proposed to control demand and the emissions. The policies provided the best results in terms of minimum emissions and the reasonable share of highway and railway mode as 70% and 30% usage for policy I, respectively. The emission calculation procedure presented in this study would provide an alternative way to make policies when there is no adequate data on emission measurement in developing countries. - Research highlights: → Emissions caused by vehicular traffic are modelled. → The pollutant emissions are calculated with estimated transport and energy demand. → All the calculations are made in line with to meet the European standards. → The calculation procedure will provide an alternative way to make policies. → The procedure will help planners to convince politicians to impose policies.

  7. Spatio-Temporal Variations in Urban Vehicular Emission in Port ...

    African Journals Online (AJOL)

    vThe increasing high volume of road traffic and congestion is a fundamental issue in Port Harcourt metropolis. The degradation of air quality arising from these is another serious dimension of the problem. This study estimated the emissions of pollutants from vehicles during traffic peak periods within parts of the city of Port ...

  8. Developing Singapore Driving Cycle for passenger cars to estimate fuel consumption and vehicular emissions

    Science.gov (United States)

    Ho, Sze-Hwee; Wong, Yiik-Diew; Chang, Victor Wei-Chung

    2014-11-01

    Singapore has pledged to attain 7-11% Business-As-Usual carbon emissions reduction by 2020. Road transport sector is a significant source of carbon emissions, estimated to be the third largest sector in Singapore. A current gap in environmental evaluation for road transport activities in Singapore is the lack of a representative driving cycle for passenger cars (64% of the total population of 974,170 vehicles). This Singapore Driving Cycle (SDC) is hence developed for Singapore roads and traffic conditions. A chase-car (instrumented vehicle) was used to collect on-road data along 12 designed routes, and circulation driving on highly utilized arterial roads (including those in Central Business District (CBD) and both inner and outer ring roads fringing the CBD area). The SDC was thus hence constructed, with consideration of road type proportions, time periods and desired distance, duration and peak-lull proportion. In essence, the SDC is a 2400-s speed-time profile to represent the driving pattern for passenger car in Singapore. Microscopic estimation model (CMEM) shows that, as compared to SDC, the New European Driving Cycle (NEDC) underestimates most of the vehicular emissions (fuel, CO2, HC and NOx by 5%, 5%, 22% and 47%, respectively) and overestimates CO by 8%. The SDC is thus more suitable than the NEDC that is currently in use in Singapore; the SDC can be used to generate more accurate fuel consumption and emissions ratings for various uses (for example, inventory of vehicular emissions and fuel economy labelling).

  9. Analysis of non-regulated vehicular emissions by extractive FTIR spectrometry: tests on a hybrid car in Mexico City

    Science.gov (United States)

    Reyes, F.; Grutter, M.; Jazcilevich, A.; González-Oropeza, R.

    2006-07-01

    A methodology to acquire valuable information on the chemical composition and evolution of vehicular emissions is presented. The analysis of the gases is performed by passing a constant flow of a sample gas from the tail-pipe into a 10 L multi-pass cell. The absorption spectra within the cell are obtained using an FTIR spectrometer at 0.5 cm-1 resolution along a 13.1 m optical path. Additionally, the total flow from the exhaust is continuously measured from a differential pressure sensor on a Pitot tube installed at the exit of the exhaust. This configuration aims to obtain a good speciation capability by coadding spectra during 30 s and reporting the emission (in g/km) of key and non-regulated pollutants, such as CO2, CO, NO, SO2, NH3, HCHO, NMHC, during predetermined driving routines. The advantages and disadvantages of increasing the acquisition frequency, as well as the effect of other parameters such as spectral resolution, cell volume and flow rate, are discussed. With the aim of testing and evaluating the proposed technique, experiments were performed on a dynamometer running FTP-75 and typical driving cycles of the Mexico City Metropolitan Area (MCMA) on a Toyota Prius hybrid vehicle. This car is an example of recent automotive technology to reach the market dedicated to reduce emissions and therefore pressing the need of low detection techniques. This study shows the potential of the proposed technique to measure and report in real time the emissions of a large variety of pollutants, even from a super ultra-low emission vehicle (SULEV). The emissions of HC's, NOx, CO and CO2 obtained here are similar to experiments performed in other locations with the same vehicle model. Some differences suggest that an inefficient combustion process and type of gasoline used in the MCMA may be partly responsible for lower CO2 and higher CO and NO emission factors. Also, a fast reduction of NO emission to very low values is observed after cold ignition, giving rise to

  10. Impact of vehicular emissions on the formation of fine particles in the Sao Paulo Metropolitan Area: a numerical study with the WRF-Chem model

    Directory of Open Access Journals (Sweden)

    A. Vara-Vela

    2016-01-01

    Full Text Available The objective of this work is to evaluate the impact of vehicular emissions on the formation of fine particles (PM2.5;  ≤  2.5 µm in diameter in the Sao Paulo Metropolitan Area (SPMA in Brazil, where ethanol is used intensively as a fuel in road vehicles. The Weather Research and Forecasting with Chemistry (WRF-Chem model, which simulates feedbacks between meteorological variables and chemical species, is used as a photochemical modelling tool to describe the physico-chemical processes leading to the evolution of number and mass size distribution of particles through gas-to-particle conversion. A vehicular emission model based on statistical information of vehicular activity is applied to simulate vehicular emissions over the studied area. The simulation has been performed for a 1-month period (7 August–6 September 2012 to cover the availability of experimental data from the NUANCE-SPS (Narrowing the Uncertainties on Aerosol and Climate Changes in Sao Paulo State project that aims to characterize emissions of atmospheric aerosols in the SPMA. The availability of experimental measurements of atmospheric aerosols and the application of the WRF-Chem model made it possible to represent some of the most important properties of fine particles in the SPMA such as the mass size distribution and chemical composition, besides allowing us to evaluate its formation potential through the gas-to-particle conversion processes. Results show that the emission of primary gases, mostly from vehicles, led to a production of secondary particles between 20 and 30 % in relation to the total mass concentration of PM2.5 in the downtown SPMA. Each of PM2.5 and primary natural aerosol (dust and sea salt contributed with 40–50 % of the total PM10 (i.e. those  ≤  10 µm in diameter concentration. Over 40 % of the formation of fine particles, by mass, was due to the emission of hydrocarbons, mainly aromatics. Furthermore, an increase in the

  11. Impact of vehicular emissions on the formation of fine particles in the Sao Paulo Metropolitan Area: a numerical study with the WRF-Chem model

    Science.gov (United States)

    Vara-Vela, A.; Andrade, M. F.; Kumar, P.; Ynoue, R. Y.; Muñoz, A. G.

    2016-01-01

    The objective of this work is to evaluate the impact of vehicular emissions on the formation of fine particles (PM2.5; ≤ 2.5 µm in diameter) in the Sao Paulo Metropolitan Area (SPMA) in Brazil, where ethanol is used intensively as a fuel in road vehicles. The Weather Research and Forecasting with Chemistry (WRF-Chem) model, which simulates feedbacks between meteorological variables and chemical species, is used as a photochemical modelling tool to describe the physico-chemical processes leading to the evolution of number and mass size distribution of particles through gas-to-particle conversion. A vehicular emission model based on statistical information of vehicular activity is applied to simulate vehicular emissions over the studied area. The simulation has been performed for a 1-month period (7 August-6 September 2012) to cover the availability of experimental data from the NUANCE-SPS (Narrowing the Uncertainties on Aerosol and Climate Changes in Sao Paulo State) project that aims to characterize emissions of atmospheric aerosols in the SPMA. The availability of experimental measurements of atmospheric aerosols and the application of the WRF-Chem model made it possible to represent some of the most important properties of fine particles in the SPMA such as the mass size distribution and chemical composition, besides allowing us to evaluate its formation potential through the gas-to-particle conversion processes. Results show that the emission of primary gases, mostly from vehicles, led to a production of secondary particles between 20 and 30 % in relation to the total mass concentration of PM2.5 in the downtown SPMA. Each of PM2.5 and primary natural aerosol (dust and sea salt) contributed with 40-50 % of the total PM10 (i.e. those ≤ 10 µm in diameter) concentration. Over 40 % of the formation of fine particles, by mass, was due to the emission of hydrocarbons, mainly aromatics. Furthermore, an increase in the number of small particles impaired the

  12. Establishing a link between vehicular PM sources and PM measurements in urban street canyons.

    Science.gov (United States)

    Eisner, Alfred D; Richmond-Bryant, Jennifer; Wiener, Russell W; Hahn, Intaek; Drake-Richman, Zora E; Ellenson, William D

    2009-12-01

    The Brooklyn Traffic Real-Time Ambient Pollutant Penetration and Environmental Dispersion (B-TRAPPED) study, conducted in Brooklyn, NY, USA, in 2005, was designed with multiple goals in mind, two of which were contaminant source characterization and street canyon transport and dispersion monitoring. In the portion of the study described here, synchronized wind velocity and azimuth as well as particulate matter (PM) concentrations at multiple locations along 33rd Street were used to determine the feasibility of using traffic emissions in a complex urban topography as a sole tracer for studying urban contaminant transport. We demonstrate in this paper that it is possible to link downwind concentrations of contaminants in an urban street canyon to the vehicular traffic cycle using Eigen-frequency analysis. In addition, multivariable circular histograms are used to establish directional frequency maxima for wind velocity and contaminant concentration.

  13. Ultrasonic fluid quantity measurement in dynamic vehicular applications a support vector machine approach

    CERN Document Server

    Terzic, Jenny; Nagarajah, Romesh; Alamgir, Muhammad

    2013-01-01

    Accurate fluid level measurement in dynamic environments can be assessed using a Support Vector Machine (SVM) approach. SVM is a supervised learning model that analyzes and recognizes patterns. It is a signal classification technique which has far greater accuracy than conventional signal averaging methods. Ultrasonic Fluid Quantity Measurement in Dynamic Vehicular Applications: A Support Vector Machine Approach describes the research and development of a fluid level measurement system for dynamic environments. The measurement system is based on a single ultrasonic sensor. A Support Vector Machines (SVM) based signal characterization and processing system has been developed to compensate for the effects of slosh and temperature variation in fluid level measurement systems used in dynamic environments including automotive applications. It has been demonstrated that a simple ν-SVM model with Radial Basis Function (RBF) Kernel with the inclusion of a Moving Median filter could be used to achieve the high levels...

  14. Tecnical Note: Analysis of non-regulated vehicular emissions by extractive FTIR spectrometry: tests on a hybrid car in Mexico City

    Science.gov (United States)

    Reyes, F.; Grutter, M.; Jazcilevich, A.; González-Oropeza, R.

    2006-11-01

    A methodology to acquire valuable information on the chemical composition and evolution of vehicular emissions is presented. The analysis of the gases is performed by passing a constant flow of a sample gas from the tail-pipe into a 10 L multi-pass cell. The absorption spectra within the cell are obtained using an FTIR spectrometer at 0.5 cm-1 resolution along a 13.1 m optical path. Additionally, the total flow from the exhaust is continuously measured from a differential pressure sensor on a textit{Pitot} tube installed at the exit of the exhaust. This configuration aims to obtain a good speciation capability by coadding spectra during 30 s and reporting the emission (in g/km) of both criteria and non-regulated pollutants, such as CO2, CO, NO, SO2, NH3, HCHO and some NMHC, during predetermined driving cycles. The advantages and disadvantages of increasing the measurement frequency, as well as the effect of other parameters such as spectral resolution, cell volume and flow rate, are discussed. To test and evaluate the proposed technique, experiments were performed on a dynamometer running FTP-75 and typical driving cycles for the Mexico City Metropolitan Area (MCMA) on a Toyota Prius hybrid vehicle. This car is an example of recent marketed automotive technology dedicated to reduced emissions, increasing the need for sensitive detection techniques. This study shows the potential of the proposed technique to measure and report in real time the emissions of a large variety of pollutants, even from a super ultra-low emission vehicle (SULEV). The emissions of HC's, NOx, CO and CO2 obtained here were compared to experiments performed in other locations with the same model vehicle. The proposed technique provides a tool for future studies comparing in detail the emissions of vehicles using alternative fuels and emission control systems.

  15. Tecnical Note: Analysis of non-regulated vehicular emissions by extractive FTIR spectrometry: tests on a hybrid car in Mexico City

    Directory of Open Access Journals (Sweden)

    F. Reyes

    2006-01-01

    Full Text Available A methodology to acquire valuable information on the chemical composition and evolution of vehicular emissions is presented. The analysis of the gases is performed by passing a constant flow of a sample gas from the tail-pipe into a 10 L multi-pass cell. The absorption spectra within the cell are obtained using an FTIR spectrometer at 0.5 cm−1 resolution along a 13.1 m optical path. Additionally, the total flow from the exhaust is continuously measured from a differential pressure sensor on a extit{Pitot} tube installed at the exit of the exhaust. This configuration aims to obtain a good speciation capability by coadding spectra during 30 s and reporting the emission (in g/km of both criteria and non-regulated pollutants, such as CO2, CO, NO, SO2, NH3, HCHO and some NMHC, during predetermined driving cycles. The advantages and disadvantages of increasing the measurement frequency, as well as the effect of other parameters such as spectral resolution, cell volume and flow rate, are discussed. To test and evaluate the proposed technique, experiments were performed on a dynamometer running FTP-75 and typical driving cycles for the Mexico City Metropolitan Area (MCMA on a Toyota Prius hybrid vehicle. This car is an example of recent marketed automotive technology dedicated to reduced emissions, increasing the need for sensitive detection techniques. This study shows the potential of the proposed technique to measure and report in real time the emissions of a large variety of pollutants, even from a super ultra-low emission vehicle (SULEV. The emissions of HC's, NOx, CO and CO2 obtained here were compared to experiments performed in other locations with the same model vehicle. The proposed technique provides a tool for future studies comparing in detail the emissions of vehicles using alternative fuels and emission control systems.

  16. Emissions & Measurements - Black Carbon

    Science.gov (United States)

    Emissions and Measurement (EM) research activities performed within the National Risk Management Research Lab NRMRL) of EPA's Office of Research and Development (ORD) support measurement and laboratory analysis approaches to accurately characterize source emissions, and near sour...

  17. PCDD/PCDF and dl-PCB in the ambient air of a tropical Andean city: passive and active sampling measurements near industrial and vehicular pollution sources.

    Science.gov (United States)

    Cortés, J; González, C M; Morales, L; Abalos, M; Abad, E; Aristizábal, B H

    2014-09-01

    Concentration gradients were observed in gas and particulate phases of PCDD/F originating from industrial and vehicular sources in the densely populated tropical Andean city of Manizales, using passive and active air samplers. Preliminary results suggest greater concentrations of dl-PCB in the mostly gaseous fraction (using quarterly passive samplers) and greater concentrations of PCDD/F in the mostly particle fraction (using daily active samplers). Dioxin-like PCB predominance was associated with the semi-volatility property, which depends on ambient temperature. Slight variations of ambient temperature in Manizales during the sampling period (15°C-27°C) may have triggered higher concentrations in all passive samples. This was the first passive air sampling monitoring of PCDD/F conducted in an urban area of Colombia. Passive sampling revealed that PCDD/F in combination with dioxin-like PCB ranged from 16 WHO-TEQ2005/m(3) near industrial sources to 7 WHO-TEQ2005/m(3) in an intermediate zone-a reduction of 56% over 2.8 km. Active sampling of particulate phase PCDD/F and dl-PCB were analyzed in PM10 samples. PCDD/F combined with dl-PCB ranged from 46 WHO-TEQ2005/m(3) near vehicular sources to 8 WHO-TEQ2005/m(3) in the same intermediate zone, a reduction of 83% over 2.6 km. Toxic equivalent quantities in both PCDD/F and dl-PCB decreased toward an intermediate zone of the city. Variations in congener profiles were consistent with variations expected from nearby sources, such as a secondary metallurgy plant, areas of concentrated vehicular emissions and a municipal solid waste incinerator (MSWI). These variations in congener profile measurements of dioxins and dl-PCBs in passive and active samples can be partly explained by congener variations expected from the various sources. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Relative impact of on-road vehicular and point-source industrial emissions of air pollutants in a medium-sized Andean city

    Science.gov (United States)

    González, C. M.; Gómez, C. D.; Rojas, N. Y.; Acevedo, H.; Aristizábal, B. H.

    2017-03-01

    Cities in emerging countries are facing a fast growth and urbanization; however, the study of air pollutant emissions and its dynamics is scarce, making their populations vulnerable to potential effects of air pollution. This situation is critical in medium-sized urban areas built along the tropical Andean mountains. This work assesses the contribution of on-road vehicular and point-source industrial activities in the medium-sized Andean city of Manizales, Colombia. Annual fluxes of criteria pollutants, NMVOC, and greenhouse gases were estimated. Emissions were dominated by vehicular activity, with more than 90% of total estimated releases for the majority of air pollutants. On-road vehicular emissions for CO (43.4 Gg/yr) and NMVOC (9.6 Gg/yr) were mainly associated with the use of motorcycles (50% and 81% of total CO and NMVOC emissions respectively). Public transit buses were the main source of PM10 (47%) and NOx (48%). The per-capita emission index was significantly higher in Manizales than in other medium-sized cities, especially for NMVOC, CO, NOx and CO2. The unique mountainous terrain of Andean cities suggest that a methodology based on VSP model could give more realistic emission estimates, with additional model components that include slope and acceleration. Food and beverage facilities were the main contributors of point-source industrial emissions for PM10 (63%), SOx (55%) and NOx (45%), whereas scrap metal recycling had high emissions of CO (73%) and NMVOC (47%). Results provide the baseline for ongoing research in atmospheric modeling and urban air quality, in order to improve the understanding of air pollutant fluxes, transport and transformation in the atmosphere. In addition, this emission inventory could be used as a tool to identify areas of public health exposure and provide information for future decision makers.

  19. The role of inspection and maintenance in controlling vehicular emissions in Kathmandu valley, Nepal

    Science.gov (United States)

    Faiz, Asif; Bahadur Ale, Bhakta; Nagarkoti, Ram Kumar

    Motor vehicles are a major source of air pollutant emissions in Kathmandu valley, Nepal. In-use vehicle emission limits were first introduced in Nepal in 1998 and updated in 2000. The emission regulations for gasoline vehicles limit CO emissions to 3-4.5% by volume and HC emissions to 1000 ppm for four-wheeled vehicles, and 7800 ppm for two- and three- wheelers. Emission limits for LPG/CNG vehicles are 3% for CO and 1000 ppm for HC. For diesel vehicles, smoke density must not exceed 65-75 HSU depending on the age of the vehicle. The Government operates a rudimentary inspection and maintenance (I/M) program based on an idle engine test, utilizing an exhaust gas analyzer (for gasoline/LPG/CNG vehicles) and an opacimeter for diesel vehicles. The I/M program is confined to four-wheeled vehicles and occasional three-wheelers. The inspections are required at least once a year and are conducted at designated vehicle testing stations. The I/M program is supplemented by roadside checks. This paper is based on the findings of an analysis of vehicle emissions test data for the period June 2000 to July 2002, covering some 45,000 data sets. Each data set includes information on vehicle type and ownership, the model year, and CO/HC test emission values. The analysis reported in this paper covers the characteristics and statistical distribution of emissions from gasoline-fuelled vehicles, including the impact of gross emitters. The effects of vehicle age, model year (with or without catalysts), usage, and ownership (private vs. public) on emissions of gasoline-fuelled vehicles are discussed. The findings for diesel vehicles have been reported earlier by Ale and Nagarkoti (2003b. Evaluation of Kathmandu valley inspection and maintenance program on diesel vehicles. Journal of the Institute of Engineering 3(1)). This study identifies the limitations of the current I/M program, given that it does not include 70% of the fleet consisting of two-wheelers and concludes with proposed

  20. Measurements of ultrafine particles and other vehicular pollutants inside school buses in South Texas

    Science.gov (United States)

    Zhang, Qunfang; Zhu, Yifang

    2010-01-01

    Increasing evidence has demonstrated toxic effects of vehicular emitted ultrafine particles (UFPs, diameter pollutants, especially UFPs, was measured inside four diesel-powered school buses. Two 1990 and two 2006 model year diesel-powered school buses were selected to represent the age extremes of school buses in service. Each bus was driven on two routine bus runs to study school children's exposure under different transportation conditions in South Texas. The number concentration and size distribution of UFPs, total particle number concentration, PM 2.5, PM 10, black carbon (BC), CO, and CO 2 levels were monitored inside the buses. The average total particle number concentrations observed inside the school buses ranged from 7.3 × 10 3 to 3.4 × 10 4 particles cm -3, depending on engine age and window position. When the windows were closed, the in-cabin air pollutants were more likely due to the school buses' self-pollution. The 1990 model year school buses demonstrated much higher air pollutant concentrations than the 2006 model year ones. When the windows were open, the majority of in-cabin air pollutants came from the outside roadway environment with similar pollutant levels observed regardless of engine ages. The highest average UFP concentration was observed at a bus transfer station where approximately 27 idling school buses were queued to load or unload students. Starting-up and idling generated higher air pollutant levels than the driving state. Higher in-cabin air pollutant concentrations were observed when more students were on board.

  1. Signatures of vehicular emissions and human health risk assessment of road dust in selected roads of Accra, Ghana

    International Nuclear Information System (INIS)

    Manukure, A.S.

    2009-06-01

    Street dust samples were collected from Mallam Junction-Weija road, John Teye-Pokuase road, Tema Motorway (near Ashiaman overhead) and Tetteh Quarshie interchange in Accra. The samples were segregated into grain sizes between 250μm-100μm and less than 100μm. Energy dispersive X-ray florescence technique was used to determine the elemental compositions. In all twenty (20) elements were identified: K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Zr and Pb. The results show significant concentration levels of K, Ca, Ti Pb, Zn, Cu, Mn, Fe, Rb, Sr, Y, Zr and Cr in all the samples. Ultra violet visible spectrophotometer was used to determine the concentrations of SO 4 2- and NO 3 - . Enrichment factors calculated for the elements show high enrichment of Pb, V, Zn, Cu, Zr, Cr, Br and Pb from the sample sites. There was no indication of significant anthropogenic contribution of manganese (Mn) which gave enrichment factor values in the range of 0.57- 1.00 in the road dust. The average SO 4 2- and NO 3 - concentration ranged between 17.69mg/kg-28.86mg/kg and 14.76mg/kg-23.70mg/kg respectively. The principal component analysis was used to identify sources and their contributions. The sources identified were natural crust, brake wear, tyre wear and vehicle exhaust emission. The results show high levels of vehicle non-exhaust emission than vehicular exhaust emission. A risk assessment of selected heavy metal contaminants from all sites indicate that Pb which is the most toxic among the elements gave Hazard Index (H-I) value in the range of 0.14 - 0.62 which is less than the safe level of one (1). It was also observed that ingestion pathway which gave HI value in the range of 1.1- 2.3 showed the highest risk of exposure. Tetteh Quarshie Interchange gave the highest cumulative risk exposure. (au)

  2. Contributions of Vehicular Traffic to Carbon Dioxide Emissions in Kaduna and Abuja, Northern Nigeria

    Directory of Open Access Journals (Sweden)

    Peter Ndoke NDOKE

    2006-07-01

    Full Text Available The quantity of carbon dioxide (CO2 contributed by automobile emissions to the environment was determined at some areas in Kaduna and Abuja in Northern Nigeria. Five census stations were selected in each of the two towns. In Kaduna, Jabi road in Ungwan Rimi, Kawo Motor park, Stadium round-about, Sabo and Kasuwa (Kaduna Main Market, were selected, while Asokoro (behind ECOWAS, Area One junction, A.Y.A. junction, Wuse market bus-stop, and Mabushi round-about were selected for Abuja. A gas sampling pump and tubes that could detect carbon dioxide were used to detect the quantity of CO2 in the environment at a certain time. The results obtained show a variation in the amount of CO2 in the environment. Areas with relatively heavy congestion show a high concentration of CO2, while areas with minimal traffic show a lower concentration of CO2. Sabo in Kaduna has an average concentration of 1840 ppm being the highest, while Asokoro (behind ECOWAS, Abuja has the least average concentration of 1160 ppm. Review of literature showed that increasing CO2 levels have adverse effects such as the Greenhouse Effect, which may lead to Global Warming, as well as a number of other climatic events. These concentrations are still not high enough to cause any serious health effects but they provide a baseline study for Policy makers and Town planners.

  3. Influence of vehicular emissions on atmospheric CH4 and NMHC mixing ratios and its correlation with CO and other VOCs tracers in Mexico City

    Science.gov (United States)

    Solano-Murillo, M.; Torres-Jardón, R.; Ruiz-Suárez, L. G.; Barrera-Huertas, H.; Hernandez-Solis, J. M.

    2016-12-01

    The Mexico City Metropolitan Area (MCMA) is one of the world's largest and most polluted urban areas. A recent GHC emission inventory for MCMA suggests that vehicular emissions contribute with around 37% of CH4, followed by landfills and dump garbage areas (30%) and construction and manufacturing (27%). Contrary to other urban areas, natural gas is not the main fuel used in MCMA, neither for domestic and industrial heating, nor for transportation. Therefore, there is a great uncertainty about who is the main contributor of CH4 emissions. An intensive monitoring campaign of methane (CH4), Non-methane hydrocarbons (NMHC) and carbon monoxide (CO) was performed between February and March 2015 in southwest MCMA. Methane concentrations showed sometimes a diurnal pattern similar to those of CO and to NMHC but most of the time this similarity was lost (CH4 vs CO, R2 = 0.27; CH4 vs NMHC, R2 = 0.28). However, NMHC correlated well with CO (R2 = 0.75). The intercepts of the CH4-CO correlation resulted in [CH4] 1.8 ppm and that of the CO-NMHC correlation in [CO] 0.080 ppb. The lack of agreement between CH4 and CO indicates these species do not come from the same sources. The results suggest that vehicular emissions are not significant contributors to atmospheric CH4 and that the background methane concentration has not change significantly in 25 years. An attempt to correlate some tracers COVs tracers of vehicular and biomass burning with CH4, NMHC and CH4 is done.

  4. Carbon dioxide emission and bio-capacity indexing for transportation activities: A methodological development in determining the sustainability of vehicular transportation systems.

    Science.gov (United States)

    Labib, S M; Neema, Meher Nigar; Rahaman, Zahidur; Patwary, Shahadath Hossain; Shakil, Shahadat Hossain

    2018-06-09

    CO 2 emissions from urban traffic are a major concern in an era of increasing ecological disequilibrium. Adding to the problem net CO 2 emissions in urban settings are worsened due to the decline of bio-productive areas in many cities. This decline exacerbates the lack of capacity to sequestrate CO 2 at the micro and meso-scales resulting in increased temperatures and decreased air quality within city boundaries. Various transportation and environmental strategies have been implemented to address traffic related CO 2 emissions, however current literature identifies difficulties in pinpointing these critical areas of maximal net emissions in urban transport networks. This study attempts to close this gap in the literature by creating a new lay-person friendly index that combines CO 2 emissions from vehicles and the bio-capacity of specific traffic zones to identify these areas at the meso-scale within four ranges of values with the lowest index values representing the highest net CO 2 levels. The study used traffic volume, fuel types, and vehicular travel distance to estimate CO 2 emissions at major links in Dhaka, Bangladesh's capital city's transportation network. Additionally, using remote-sensing tools, adjacent bio-productive areas were identified and their bio-capacity for CO 2 sequestration estimated. The bio-productive areas were correlated with each traffic zone under study resulting in an Emission Bio-Capacity index (EBI) value estimate for each traffic node. Among the ten studied nodes in Dhaka City, nine had very low EBI values, correlating to very high CO 2 emissions and low bio-capacity. As a result, the study considered these areas unsustainable as traffic nodes going forward. Key reasons for unsustainability included increasing use of motorized traffic, absence of optimized signal systems, inadequate public transit options, disincentives for fuel free transport (FFT), and a decline in bio-productive areas. Copyright © 2018 Elsevier Ltd. All rights

  5. A Crowd-Based Intelligence Approach for Measurable Security, Privacy, and Dependability in Internet of Automated Vehicles with Vehicular Fog

    Directory of Open Access Journals (Sweden)

    Ashish Rauniyar

    2018-01-01

    Full Text Available With the advent of Internet of things (IoT and cloud computing technologies, we are in the era of automation, device-to-device (D2D and machine-to-machine (M2M communications. Automated vehicles have recently gained a huge attention worldwide, and it has created a new wave of revolution in automobile industries. However, in order to fully establish automated vehicles and their connectivity to the surroundings, security, privacy, and dependability always remain a crucial issue. One cannot deny the fact that such automatic vehicles are highly vulnerable to different kinds of security attacks. Also, today’s such systems are built from generic components. Prior analysis of different attack trends and vulnerabilities enables us to deploy security solutions effectively. Moreover, scientific research has shown that a “group” can perform better than individuals in making decisions and predictions. Therefore, this paper deals with the measurable security, privacy, and dependability of automated vehicles through the crowd-based intelligence approach that is inspired from swarm intelligence. We have studied three use case scenarios of automated vehicles and systems with vehicular fog and have analyzed the security, privacy, and dependability metrics of such systems. Our systematic approaches to measuring efficient system configuration, security, privacy, and dependability of automated vehicles are essential for getting the overall picture of the system such as design patterns, best practices for configuration of system, metrics, and measurements.

  6. Vehicular ad hoc network security and privacy

    CERN Document Server

    Lin, X

    2015-01-01

    Unlike any other book in this area, this book provides innovative solutions to security issues, making this book a must read for anyone working with or studying security measures. Vehicular Ad Hoc Network Security and Privacy mainly focuses on security and privacy issues related to vehicular communication systems. It begins with a comprehensive introduction to vehicular ad hoc network and its unique security threats and privacy concerns and then illustrates how to address those challenges in highly dynamic and large size wireless network environments from multiple perspectives. This book is richly illustrated with detailed designs and results for approaching security and privacy threats.

  7. Atmospheric and children's blood lead as indicators of vehicular traffic and other emission sources in Mumbai, India

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, R.M.; Raghunath, R.; Vinod Kumar, A.; Sastry, V.N.; Sadasivan, S. [Environmental Assessment Division, Bhabha Atomic Research Centre, 400 085 Mumbai (India)

    2001-02-21

    Average concentration of Pb in atmospheric air particulates in different suburbs of Mumbai was studied for almost a decade and its spatial and temporal profiles are discussed in relation to emission sources. In general the concentration of Pb in all the residential suburban atmosphere is well below the Central Pollution Control Board (CPCB, 1994) prescribed limit of 1.5 {mu}g m{sup -3} barring a few exceptions for some residential/industrial sites, such as those of Thane and Kurla scrap yards. The correlation between blood lead of children and air lead reveals that the blood Pb level in children could increase by 3.6 {mu}g dl{sup -1} for an incremental rise of 1.0 {mu}g Pb m{sup -3} of air. The temporal profile of air Pb values indicates a decreasing trend in residential suburbs (Khar: 1984, 0.39 {mu}g m{sup -3}; 1996, 0.17 {mu}g m{sup -3}) as well as in suburban residential areas with low traffic (Goregaon: 1984, 0.53 {mu}g m{sup -3}; 1996, 0.30 {mu}g m{sup -3})

  8. Emissivity measurements on aeronautical alloys

    International Nuclear Information System (INIS)

    Campo, L. del; Perez-Saez, R.B.; Gonzalez-Fernandez, L.; Esquisabel, X.; Fernandez, I.; Gonzalez-Martin, P.; Tello, M.J.

    2010-01-01

    The emissivity of three Ni and Co based aeronautical alloys is analyzed in this paper. These alloys are employed in high temperature environments whenever good corrosion resistance, high temperature resistance and high strength are essential. Thus, apart from the aeronautical industry, these alloys are also used in other technological applications, as for example, aerospace, nuclear reactors, and tooling. The results in this paper extend the emissivity data for these alloys available in the literature. Emissivity dependence on the radiation wavelength (2-22 μm), sample temperature (200-650 o C) and emission angle (0-85 o ) has been investigated. In addition, the effect of surface finish and oxidation has also been taken into consideration. The data in this paper have several applications, as temperature measurement of a target by pyrometry, low observability of airplanes and thermal radiation heat transfer simulation in airplane nozzles or furnaces.

  9. Emissivity measurements on aeronautical alloys

    Energy Technology Data Exchange (ETDEWEB)

    Campo, L. del, E-mail: leire.del-campo@cnrs-orleans.f [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Perez-Saez, R.B., E-mail: raul.perez@ehu.e [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Instituto de Sintesis y Estudio de Materiales, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao (Spain); Gonzalez-Fernandez, L. [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Esquisabel, X.; Fernandez, I. [Industria de Turbo Propulsores, S.A., Planta de Zamudio, Edificio 300, 48170 Zamudio, Bizkaia (Spain); Gonzalez-Martin, P. [Industria de Turbo Propulsores, S.A., Parque empresarial San Fernando, Avda. Castilla 2, 28830 San Fernando de Henares, Madrid (Spain); Tello, M.J. [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Instituto de Sintesis y Estudio de Materiales, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao (Spain)

    2010-01-21

    The emissivity of three Ni and Co based aeronautical alloys is analyzed in this paper. These alloys are employed in high temperature environments whenever good corrosion resistance, high temperature resistance and high strength are essential. Thus, apart from the aeronautical industry, these alloys are also used in other technological applications, as for example, aerospace, nuclear reactors, and tooling. The results in this paper extend the emissivity data for these alloys available in the literature. Emissivity dependence on the radiation wavelength (2-22 {mu}m), sample temperature (200-650 {sup o}C) and emission angle (0-85{sup o}) has been investigated. In addition, the effect of surface finish and oxidation has also been taken into consideration. The data in this paper have several applications, as temperature measurement of a target by pyrometry, low observability of airplanes and thermal radiation heat transfer simulation in airplane nozzles or furnaces.

  10. Emissions & Measurements - Black Carbon | Science ...

    Science.gov (United States)

    Emissions and Measurement (EM) research activities performed within the National Risk Management Research Lab NRMRL) of EPA's Office of Research and Development (ORD) support measurement and laboratory analysis approaches to accurately characterize source emissions, and near source concentrations of air pollutants. They also support integrated Agency research programs (e.g., source to health outcomes) and the development of databases and inventories that assist Federal, state, and local air quality managers and industry implement and comply with air pollution standards. EM research underway in NRMRL supports the Agency's efforts to accurately characterize, analyze, measure and manage sources of air pollution. This pamphlet focuses on the EM research that NRMRL researchers conduct related to black carbon (BC). Black Carbon is a pollutant of concern to EPA due to its potential impact on human health and climate change. There are extensive uncertainties in emissions of BC from stationary and mobile sources. Emissions and Measurement (EM) research activities performed within the National Risk Management Research Lab NRMRL) of EPA's Office of Research and Development (ORD)

  11. Vehicular Networking Conference (VNC)

    NARCIS (Netherlands)

    Altintas, O.; Chen, W.; Heijenk, Geert; Dressler, F.; Ekici, E.; Kargl, Frank; Shigeno, H.; Dietzel, Stefan

    2011-01-01

    On behalf of the Organizing Committee, we would like to welcome you to the third edition of the IEEE Vehicular Networking Conference (IEEE VNC 2011) in Amsterdam, the Netherlands. IEEE VNC is a unique conference sponsored by both the IEEE Communications Society and the IEEE Intelligent

  12. Towards autonomous vehicular clouds

    Directory of Open Access Journals (Sweden)

    Stephan Olariu

    2011-09-01

    Full Text Available The dawn of the 21st century has seen a growing interest in vehicular networking and its myriad potential applications. The initial view of practitioners and researchers was that radio-equipped vehicles could keep the drivers informed about potential safety risks and increase their awareness of road conditions. The view then expanded to include access to the Internet and associated services. This position paper proposes and promotes a novel and more comprehensive vision namely, that advances in vehicular networks, embedded devices and cloud computing will enable the formation of autonomous clouds of vehicular computing, communication, sensing, power and physical resources. Hence, we coin the term, autonomous vehicular clouds (AVCs. A key feature distinguishing AVCs from conventional cloud computing is that mobile AVC resources can be pooled dynamically to serve authorized users and to enable autonomy in real-time service sharing and management on terrestrial, aerial, or aquatic pathways or theaters of operations. In addition to general-purpose AVCs, we also envision the emergence of specialized AVCs such as mobile analytics laboratories. Furthermore, we envision that the integration of AVCs with ubiquitous smart infrastructures including intelligent transportation systems, smart cities and smart electric power grids will have an enormous societal impact enabling ubiquitous utility cyber-physical services at the right place, right time and with right-sized resources.

  13. Physiological, biochemical and defense system responses of parthenium hysterophorus to vehicular exhaust pollution

    International Nuclear Information System (INIS)

    Khalid, N.; Hussain, M.; Hameed, M.; Ahmad, R.

    2017-01-01

    Pollution caused by vehicular exhaust emissions detrimentally affect plants and other living beings. This investigation was carried out to evaluate the effects of vehicular exhaust pollutants on Parthenium hysterophorus at various sites along two major roads [Pindi Bhattian to Lillah (M-2) and Faisalabad to Sargodha (FSR)]in the Punjab, Pakistan. Control samples of P. hysterophorus were also collected from 100m away from the roads. Chlorophyll contents, photosynthetic rate, transpiration rate, stomatal conductance, substomatal CO/sub 2/ concentration, water use efficiency, total free amino acids and total antioxidant activity of P. hysterophorus were measured. The results depicted significant reductions in chlorophyll a, chlorophyll b, total chlorophyll and carotenoid contents of P. hysterophorus. Likewise, reduction in stomatal conductance was also recorded which resulted in lowered photosynthetic and transpiration rates. The overall reduction in photosynthetic rate of P. hysterophorus was 30.92% and 35.38% along M-2 and FSR roads, respectively. The limited photosynthesis resulted in increased levels of sub stomatal /sub 2/ concentration and water use efficiency. The elevated levels of free amino acids and total antioxidant activity were noted and could be attributed to activation of plant's defense system to cope with the deleterious effects of vehicular air pollutants. The significant correlations between various attributes of P. hysterophorus with traffic density signifies the stress caused by vehicular emissions. (author)

  14. Apparatus for measuring radioactive emissions

    International Nuclear Information System (INIS)

    Bohme, R.C.; Lazerson, M.M.

    1984-01-01

    Apparatus for measuring radioactive emissions from moving radioactive material comprises at least one radiation detector in a housing serving as a first radiation shield and in which at least one groove is formed to expose at least a portion of a receptor surface of the detector. The groove extends transverse to the direction of movement of the material over the detector. A second radiation shield may be located between at least a portion of the first shield and the detector. The material of the second shield is inherently less contaminated and emits secondary excitation radiation of lower energy than the first material. (author)

  15. On vehicular traffic data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brics, Martins; Mahnke, Reinhard [Institute of Physics, Rostock University (Germany)

    2011-07-01

    This contribution consists of analysis of empirical vehicular traffic flow data. The main focus lies on the Next Generation Simulation (NGSIM) data. The first findings show that there are artificial structures within the data due to errors of monitoring as well as smoothing position measurement data. As a result speed data show discretisation in 5 feet per second. The aim of this investigation is to construct microscopic traffic flow models which are in agreement to the analysed empirical data. The ongoing work follows the subject of research summarized by Christof Liebe in his PhD thesis entitled ''Physics of traffic flow: Empirical data and dynamical models'' (Rostock, 2010).

  16. Vehicular engine design

    CERN Document Server

    Hoag, Kevin

    2016-01-01

    This book provides an introduction to the design and mechanical development of reciprocating piston engines for vehicular applications. Beginning from the determination of required displacement and performance, coverage moves into engine configuration and architecture. Critical layout dimensions and design trade-offs are then presented for pistons, crankshafts, engine blocks, camshafts, valves, and manifolds.  Coverage continues with material strength and casting process selection for the cylinder block and cylinder heads. Each major engine component and sub-system is then taken up in turn, from lubrication system, to cooling system, to intake and exhaust systems, to NVH. For this second edition latest findings and design practices are included, with the addition of over sixty new pictures and many new equations.

  17. Emissivity Measurements of Additively Manufactured Materials

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Robert Vaughn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reid, Robert Stowers [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baker, Andrew M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lucero, Briana [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bernardin, John David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-25

    The emissivity of common 3D printing materials such as ABS and PLA were measured using a reflectivity meter and have the measured value of approximately 0.92. Adding a conductive material to the filament appears to cause a decrease in the emissivity of the surface. The angular dependence of the emissivity and the apparent temperature was measured using a FLIR infrared camera showing that the emissivity does not change much for shallow angles less than 40 angular degrees, and drops off dramatically after 70 angular degrees.

  18. Current technologies in vehicular communication

    CERN Document Server

    Dimitrakopoulos, George

    2017-01-01

    This book provides a concise and comprehensive overview of vehicular communication technologies. It classifies all relevant standards, protocols and applications, so as to enable the reader to gain a holistic approach towards the subject of vehicular communications. The primary methods are algorithmic processes and simulation results. First, an overview and classification of vehicular technologies is presented. Then, the book focuses on specific applications of V2V and V2I communications. Special attention is given to recent research and development results regarding R&D projects in the field, in cooperation with car manufacturing companies and universities at a global level. Designed to facilitate understanding of vehicle to vehicle and vehicle to infrastructure technologies, this textbook is appropriate for undergraduate and graduate students of vehicular communications or mobile networks.

  19. Accoustic emission measurements during phase change

    Energy Technology Data Exchange (ETDEWEB)

    Tensi, H M; Radtke, W [Technische Univ. Muenchen (Germany, F.R.). Inst. fuer Werkstoff- und Verarbeitungswissenschaften

    1978-07-01

    Acoustic emission measurements during solidification and melting of metals are heavily disturbed by noise originating from frictional movements between crucible and specimen. These disturbances may be cancelled by means of specially arranged crucibles. Thus it was possible to use acoustic emission generated during solidification of residual eutectic liquid for real-time judgement of macrosegregation and microsegregation. With the help of crucibles made of silicone tubes the effect of melting velocity and concentration on acoustic emission generated by melting of bismuth and bismuth alloys was measured.

  20. On-road particulate emission measurement

    Science.gov (United States)

    Mazzoleni, Claudio

    Particulate matter (PM) suspended in the atmosphere has harmful health effects, contributes to visibility impairment, and affects atmospheric radiative transfer, thereby contributing to global change. Vehicles contribute substantially to the ambient PM concentration in urban areas, yet the fraction of ambient PM originating from vehicle emissions is poorly characterized because suitable measurement methods have not been available. This dissertation describes the development and the use of a new vehicle emission remote sensing system (VERSS) for the on-road measurement of PM emission factors for vehicles. The PM VERSS measures PM by ultraviolet backscattering and transmission. PM backscattering and transmission mass efficiencies have been calculated from Mie theory based on an homogeneous spherical model for gasoline particles and on a two-layers, spherical model for diesel particles. The VERSS was used in a large-scale study in Las Vegas, NV. A commercial gaseous VERSS was used for the measurement of gaseous emission factors (i.e., carbon monoxide, hydrocarbons, and nitrogen oxide). Speed and acceleration were also measured for each vehicle. A video image of each vehicle's rear license plate was acquired and license plate numbers were matched with the Clark County department of motor vehicle database to retrieve vehicle information such as model year, vehicle weight category and engine ignition type. PM VERSS has precisely estimated PM fleet average emission factors and clearly shown the dependence of PM emission factors on vehicle model year. Under mostly hot-stabilized operation, diesel vehicle PM emission factors are about 25 times higher than those of gasoline vehicles. Furthermore, the fleet frequency distributions of PM emission factors are highly skewed, meaning that most of the fleet emission factor is accounted for by a small portion of the fleet. The PM VERSS can measure PM emission factors for these high emitting vehicles on an individual basis. PM

  1. Deuterium measurement by emission spectrometry

    International Nuclear Information System (INIS)

    Niemann, E.G.; Heilig, K.; Dumke, I.

    1978-01-01

    The method makes it possible to determine the relative deuterium content of enriched water samples. For this, the relative intensities of the Hα and Dα lines are measured which are emitted by a high-frequency discharge in water vapour. Although the method is not as exact as mass spectrometry, it has the following advantages: - Easy sample preparation (no reduction necessary); - samples of highly different enrichment can be measured one after the other without the danger of memory effects; - much lower apparatus and cost expenditure. The necessary sample size is about the same in both methods. (orig.) [de

  2. Measurement of light emission in scintillation vials

    International Nuclear Information System (INIS)

    Duran Ramiro, M. Teresa; Garcia-Torano, Eduardo

    2005-01-01

    The efficiency and energy resolution of liquid scintillation counting (LSC) systems are strongly dependent on the optical characteristics of scintillators, vials, and reflectors. This article presents the results of measurements of the light-emission profile of scintillation vials. Two measurement techniques, autoradiographs and direct measurements with a photomultiplier tube, have been used to obtain light-emission distribution for standard vials of glass, etched glass and polyethylene. Results obtained with both techniques are in good agreement. For the first time, the effect of the meniscus in terms of light contribution has been numerically estimated. These results can help design LSC systems that are more efficient in terms of light collection

  3. 78 FR 65594 - Vehicular Repeaters

    Science.gov (United States)

    2013-11-01

    ... coordinators estimate the effect on coordination fees? Does the supposed benefit that mobile repeater stations... allow the licensing and operation of vehicular repeater systems and other mobile repeaters by public... email: [email protected] or phone: 202-418- 0530 or TTY: 202-418-0432. For detailed instructions for...

  4. Data Dissemination in Vehicular Environments

    NARCIS (Netherlands)

    de Souza Schwartz, Ramon

    2013-01-01

    In the last few decades, Intelligent Transportation Systems (ITS) have been deployed to reduce congestion, enhance mobility, and help save lives. Among the various technologies incorporated is vehicular communication which consists in equipping vehicles with inexpensive wireless devices to enable a

  5. Measurement of Emissivity of Porous Ceramic Materials

    OpenAIRE

    BÜYÜKALACA, Orhan

    1998-01-01

    In this study, measurements of spectral and total emissivities of seven different porous ceramic materials and one ceramic fibre material are reported. Measurements were made for wavelength range from 1.2 µm to 20 µm and temperature range from 200 °C to 700 °C. It was found that total emissivity increases with increase of pore size but decreases with increase of temperature. The results showed all the porous ceramic materials tested to be much better than ceramic fibre in terms of total em...

  6. Wireless vehicular networks for car collision avoidance

    CERN Document Server

    2013-01-01

    Wireless Vehicular Networks for Car Collision Avoidance focuses on the development of the ITS (Intelligent Transportation Systems) in order to minimize vehicular accidents. The book presents and analyses a range of concrete accident scenarios while examining the causes of vehicular collision and proposing countermeasures based on wireless vehicular networks. The book also describes the vehicular network standards and quality of service mechanisms focusing on improving critical dissemination of safety information. With recommendations on techniques and protocols to consider when improving road safety policies in order to minimize crashes and collision risks.

  7. Assessment of real driving emissions via portable emission measurement system

    Science.gov (United States)

    Clenci, A.; Sălan, V.; Niculescu, R.; Iorga-Simăn, V.; Zaharia, C.

    2017-10-01

    The European Commission approved a so-called Real Driving Emission (RDE) test in response to the criticisms to the current driving cycle used at chassis dyno for homologation purpose (NEDC): it is considered outdated and misleading since air pollutants in real driving conditions are considerably higher than the certification thresholds. So, what’s at stake is the air quality which degraded continuously despite the ever-increasing severity of the regulations during the last almost three decades. Thus, from September 2017, the RDE test will become part of the type approval process for all cars sold in Europe. As its name points out, it will include “real world driving” using a portable emissions measurement system (PEMS). The paper presents the RDE features (PEMS mounting, testing environment, boundary conditions, driving dynamics) and presents a case study on the influence of the driving style upon the tail-pipe emissions under the RDE testing. The results presented in the paper issued from the existing cooperation on this topic between University of Pitesti and Renault Technologie Roumanie

  8. Measuring techniques in emission computed tomography

    International Nuclear Information System (INIS)

    Jordan, K.; Knoop, B.

    1988-01-01

    The chapter reviews the historical development of the emission computed tomography and its basic principles, proceeds to SPECT and PET, special techniques of emission tomography, and concludes with a comprehensive discussion of the mathematical fundamentals of the reconstruction and the quantitative activity determination in vivo, dealing with radon transformation and the projection slice theorem, methods of image reconstruction such as analytical and algebraic methods, limiting conditions in real systems such as limited number of measured data, noise enhancement, absorption, stray radiation, and random coincidence. (orig./HP) With 111 figs., 6 tabs [de

  9. “Comprehensive emission measurements from prescribed ...

    Science.gov (United States)

    Simultaneous aerial- and ground-based emission sampling was conducted during prescribed burns at Eglin Air Force Base in November 2012 on a short grass/shrub field and a pine forest. Cumulative emission samples for volatile organic comounds, elemental carbon, organic carbon, chlorinated dioxins and furans, and PM2.5 and continuous samples for black carbon, particle size, and CO2 were taken. Aerial instruments were lofted using a 5 m diameter, helium-filled aerostat that was maneuvered with two remotely-controlled tethers mounted on all-terrain vehicles. A parallel set of instruments on the ground made simultaneous measurements, allowing for a comparison of ground level versus elevated measurements. Ground instruments were supplemented by additional measurements of polycyclic aromatic hydrocarbons and particle aerosol absorption and light scattering. Raw biomass was also gathered on site and tested in a laboratory combustion facility using the same array of instruments. This work compares emissions derived from aerial and ground sampling as well as field and laboratory results. This abstract will likely be the first ever prescribed burn study to compare laboratory and field emission results with results from aerial and and ground sampling. As such it will inform sampling methods for future events and determine the ability of laboratory simulations to mimic events inthe field.

  10. Acoustic Emission Stethoscope - Measurements with Acoustic Emission on Wind Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Krystof Kryniski [AaF Infrastructure, Stockholm (Sweden)

    2013-02-15

    A remote ultrasonic stethoscope, designed on mobile devices to help a maintenance team in diagnosing drive train problems, has been demonstrated. By implementing an acoustic emission technology, the operating conditions of wind turbines have been assessed by trending techniques and ultrasonic acoustic emission converted into audible sound. The new approach has been developed and tested and compared to other monitoring techniques. Acoustic emission has generally been shown to provide a number of advantages over vibration and shock pulse methods because the system is operating in a substantially higher frequency range (100 kHz) and therefore it is more immune to operation of surrounding machines and components. Quick attenuation of ultrasonic propagation waves in the drive-train structure helps to pin-point the origin of any fault as the signals are sharper and more pronounced. Further, with the intensity measurements a direction of the source of ultrasonic energy can be identified. Using a high frequency thus makes the method suitable for measuring local effects and to determine local defects since the disturbing signals from other parts are damped. Recently developed programmable sensors capable of processing signals onboard, producing quality outputs with extremely low noise-to-signal ratio, have been used. It is discussed how the new approach can lower the cost of a wind-turbine monitoring system, while at the same time making it simple and more reliable, see Appendix A. The method has been tested on rotating parts of wind-turbines, including traditionally difficult areas such as low speed main bearings and planetary gearboxes. The method developed in the project was designed to see physical processes such as friction, impacts and metal removal, occurring when machinery degrades, can be detected and notified with the developed notification system. Apart from reporting the status and displaying the changes of the pre-defined parameters or symptoms, the system has

  11. Estimation of automobile emissions and control strategies in India.

    Science.gov (United States)

    Nesamani, K S

    2010-03-15

    Rapid, but unplanned urban development and the consequent urban sprawl coupled with economic growth have aggravated auto dependency in India over the last two decades. This has resulted in congestion and pollution in cities. The central and state governments have taken many ameliorative measures to reduce vehicular emissions. However, evolution of scientific methods for emission inventory is crucial. Therefore, an attempt has been made to estimate the emissions (running and start) from on-road vehicles in Chennai using IVE model in this paper. GPS was used to collect driving patterns. The estimated emissions from motor vehicles in Chennai in 2005 were 431, 119, 46, 7, 4575, 29, and 0.41 tons/days respectively for CO, VOC, NO(x), PM, CO(2,) CH(4) and N(2)O. It is observed from the results that air quality in Chennai has degraded. The estimation revealed that two and three-wheelers emitted about 64% of the total CO emissions and heavy-duty vehicles accounted for more than 60% and 36% of the NO(x) and PM emissions respectively. About 19% of total emissions were that of start emissions. It is also estimated that on-road transport contributes about 6637 tons/day CO(2) equivalent in Chennai. This paper has further examined various mitigation options to reduce vehicular emissions. The study has concluded that advanced vehicular technology and augmentation of public transit would have significant impact on reducing vehicular emissions.

  12. Vehicular camera pedestrian detection research

    Science.gov (United States)

    Liu, Jiahui

    2018-03-01

    With the rapid development of science and technology, it has made great development, but at the same time of highway traffic more convenient in highway traffic and transportation. However, in the meantime, traffic safety accidents occur more and more frequently in China. In order to deal with the increasingly heavy traffic safety. So, protecting the safety of people's personal property and facilitating travel has become a top priority. The real-time accurate pedestrian and driving environment are obtained through a vehicular camera which are used to detection and track the preceding moving targets. It is popular in the domain of intelligent vehicle safety driving, autonomous navigation and traffic system research. Based on the pedestrian video obtained by the Vehicular Camera, this paper studies the trajectory of pedestrian detection and its algorithm.

  13. EcoMark: Evaluating Models of Vehicular Environmental Impact

    DEFF Research Database (Denmark)

    Guo, Chenjuan; Ma, Mike; Yang, Bin

    2012-01-01

    The reduction of greenhouse gas (GHG) emissions from transporta- tion is essential for achieving politically agreed upon emissions re- duction targets that aim to combat global climate change. So-called eco-routing and eco-driving are able to substantially reduce GHG emissions caused by vehicular...... the vehicle travels in. We develop an evaluation framework, called EcoMark, for such environmental impact models. In addition, we survey all eleven state-of-the-art impact models known to us. To gain insight into the capabilities of the models and to understand the effectiveness of the EcoMark, we apply...

  14. Infectious complications after vehicular trauma in the United States.

    Science.gov (United States)

    Fraser, Douglas R; Dombrovskiy, Viktor Y; Vogel, Todd R

    2011-08-01

    The purpose of this analysis was to evaluate and define the rates of infectious complications (IC) after vehicular trauma. Secondary goals were to identify the injuries associated with the greatest risk of nosocomial infection and to measure the utilization of hospital resources associated with IC and vehicular trauma. A secondary analysis of the Nationwide Inpatient Sample (2003-2007) was performed to classify major vehicular trauma injuries utilizing International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) Emergency (E) codes. The post-traumatic IC evaluated were pneumonia, urinary tract infection (UTI), sepsis, and surgical site infection (SSI). All data were analyzed by χ(2) analysis, multivariable logistic regression, and the Cochran-Armitage test for trends. A total of 784,037 vehicular trauma patients were identified (462,543 [59.0%] motor vehicle drivers, 142,283 [18.2%] motor vehicle passengers, 98,767 [12.6%] motorcyclists; 6,568 [colon injuries. After adjustment by age, sex, and co-morbidities, patients with SCI were 4.4 times as likely (95% confidence interval [CI] 4.20-4.63) and those with cranial injuries were 2.1 times as likely (95% CI 2.06-2.19) to develop IC as patients without these injuries. Secondary infection increased significantly the length of stay and hospital charges in all groups. Patients sustaining vehicular trauma in combination with SCI had the highest rate of IC. Infectious complications increased hospital resource utilization significantly after vehicular trauma. Future root-cause analysis of high-risk groups may decrease complications and hospital utilization.

  15. Measuring and controlling greenhouse gas emissions

    International Nuclear Information System (INIS)

    Bourrier, Herve; LAFONT, Bruno; Fischer, Severin; Leonard, Damien; Tutenuit, Claire

    2011-05-01

    As providing a reporting of their greenhouse gas emissions has become mandatory for a large number of French companies, this publication proposes a methodology to perform an assessment or measurement, and a control of such emissions. In its first part, it explains why measurements are required: indication of concerned gases, international consensus to limit temperature rise, definition and chronology of the main steps adopted at the international level and which must be considered in the approach adopted by enterprises in this respect. It outlines the benefits of such a measurement for the enterprise in terms of competitiveness, personnel commitment, new markets and products, image, compliance with the law, operational and financial aspects, and so on. It identifies the various stakeholders to be informed: civil society, financial community, public authorities, clients and consumers, personnel, suppliers. It outlines the diversity and evolution of legal frameworks at the international level as well as at national levels. While evoking many examples of French companies (SNCF, EDF, Seche Environnement, RTE, Michelin, Arcelormittal, AREVA, Air France, EADS-Airbus, AXA, Veolia, and so on), the next part addresses how to measure emissions. It outlines the complexity of the methodological landscape with its various criteria, evokes the various existing standards, outlines the distinction between organisation-based, product-based and project-based approaches, and the distinction between direct and indirect emissions in relationship with the notion of scope. It comments the existence of sector-based methodologies and guidelines, and discusses some difficulties and methodological decisions. The third part proposes some lessons learned from the experience which could lead to a harmonisation of methodologies, proposes a synthesis of reporting approaches, outlines risks and opportunities related to communication

  16. Transient particle emission measurement with optical techniques

    Science.gov (United States)

    Bermúdez, Vicente; Luján, José M.; Serrano, José R.; Pla, Benjamín

    2008-06-01

    Particulate matter is responsible for some respiratory and cardiovascular diseases. In addition, it is one of the most important pollutants of high-speed direct injection (HSDI) passenger car engines. Current legislation requires particulate dilution tunnels for particulate matter measuring. However for development work, dilution tunnels are expensive and sometimes not useful since they are not able to quantify real-time particulate emissions during transient operation. In this study, the use of a continuous measurement opacimeter and a fast response HFID is proven to be a good alternative to obtain instantaneous particle mass emissions during transient operation (due to particulate matter consisting mainly of soot and SOF). Some methods and correlations available from literature, but developed for steady conditions, are evaluated during transient operation by comparing with mini-tunnel measurements during the entire MVEG-A transient cycle. A new correlation was also derived from this evaluation. Results for soot and SOF (obtained from the new correlation proposed) are compared with soot and SOF captured with particulate filters, which have been separated by means of an SOF extraction method. Finally, as an example of ECU design strategies using these sort of correlations, the EGR valve opening is optimized during transient operation. The optimization is performed while simultaneously taking into account instantaneous fuel consumption, particulate emissions (calculated with the proposed correlation) and other regulated engine pollutants.

  17. APPLICATION OF FUZZY C-MEANS CLUSTERING TECHNIQUE IN VEHICULAR POLLUTION

    Directory of Open Access Journals (Sweden)

    Samarjit Das

    2013-07-01

    Full Text Available Presently in most of the urban areas all over the world, due to the exponential increase in traffic, vehicular pollution has become one of the key contributors to air pollution. As uncertainty prevails in the process of designating the level of pollution of a particular region, a fuzzy method can be applied to see the membership values of that region to a number of predefined clusters. Also, due to the existence of different pollutants in vehicular pollution, the data used to represent it are in the form of numerical vectors. In our work, we shall apply the fuzzy c-means technique of Bezdek on a dataset representing vehicular pollution to obtain the membership values of pollution due to vehicular emission of a city to one or more of some predefined clusters. We shall try also to see the benefits of adopting a fuzzy approach over the traditional way of determining the level of pollution of the particular region

  18. A new oxidation flow reactor for measuring secondary aerosol formation of rapidly changing emission sources

    Science.gov (United States)

    Simonen, Pauli; Saukko, Erkka; Karjalainen, Panu; Timonen, Hilkka; Bloss, Matthew; Aakko-Saksa, Päivi; Rönkkö, Topi; Keskinen, Jorma; Dal Maso, Miikka

    2017-04-01

    Oxidation flow reactors (OFRs) or environmental chambers can be used to estimate secondary aerosol formation potential of different emission sources. Emissions from anthropogenic sources, such as vehicles, often vary on short timescales. For example, to identify the vehicle driving conditions that lead to high potential secondary aerosol emissions, rapid oxidation of exhaust is needed. However, the residence times in environmental chambers and in most oxidation flow reactors are too long to study these transient effects ( ˜ 100 s in flow reactors and several hours in environmental chambers). Here, we present a new oxidation flow reactor, TSAR (TUT Secondary Aerosol Reactor), which has a short residence time ( ˜ 40 s) and near-laminar flow conditions. These improvements are achieved by reducing the reactor radius and volume. This allows studying, for example, the effect of vehicle driving conditions on the secondary aerosol formation potential of the exhaust. We show that the flow pattern in TSAR is nearly laminar and particle losses are negligible. The secondary organic aerosol (SOA) produced in TSAR has a similar mass spectrum to the SOA produced in the state-of-the-art reactor, PAM (potential aerosol mass). Both reactors produce the same amount of mass, but TSAR has a higher time resolution. We also show that TSAR is capable of measuring the secondary aerosol formation potential of a vehicle during a transient driving cycle and that the fast response of TSAR reveals how different driving conditions affect the amount of formed secondary aerosol. Thus, TSAR can be used to study rapidly changing emission sources, especially the vehicular emissions during transient driving.

  19. Estudo do processo de dispersão de emissões veiculares em uma microrregião de Belo Horizonte (MG utilizando simulação numérica Study of the dispersion process of vehicular emissions at a specific site in Belo Horizonte (MG, Brazil, using numerical simulation

    Directory of Open Access Journals (Sweden)

    Fernanda Vasconcelos Fonseca Tavares

    2010-12-01

    Full Text Available O modelo CAL3QHCR (California Line Source for Queuing & Hot Spot Calculations Refined foi utilizado para avaliar a contribuição das emissões de material particulado (MP10 e MP2,5 de origem veicular na qualidade do ar de uma microrregião do centro de Belo Horizonte (MG. Os resultados de concentração obtidos nas simulações foram comparados com dados experimentais de concentração de MP10 e MP2,5, obtidos a partir da amostragem desses poluentes em uma estação de monitoramento da qualidade do ar localizada na área de estudo. Para todos os cenários, os valores de concentração previstos pelo modelo foram menores do que os observados. Uma análise de sensibilidade revelou que o fator de emissão veicular é o parâmetro que mais influencia os resultados das simulações, indicando a necessidade de realização de um maior número de pesquisas sobre o tema no Brasil.The CAL3QHCR (California Line Source for Queuing & Hot Spot Calculations Refined model was used to assess the contribution of particulate matter (PM10 and PM2.5 from vehicular exhausts to the air quality of a specific site downtown Belo Horizonte (MG, Brazil. Concentration results obtained through simulations were compared to the experimental data of concentrations of PM10 and PM2.5 which consisted of collected samples of these pollutants from a monitoring station for air quality located in the area of the study. For all scenarios, the concentration values predicted by the model were lower than the experimental concentrations. The sensitivity analysis showed that the vehicular emission factor influenced the simulation results more than the other parameters, which points out to the need of more researches in this area in Brazil.

  20. Acoustic emission measurement during instrumented impact tests

    International Nuclear Information System (INIS)

    Crostack, H.A.; Engelhardt, A.H.

    1983-01-01

    Results of instrumented impact tests are discussed. On the one hand the development of the loading process at the hammer tup was recorded by means of a piezoelectric transducer. This instrumentation supplied a better representation of the load versus time than the conventional strain gauges. On the other hand the different types of acoustic emission occurring during a test could be separated. The acoustic emission released at the impact of the hammer onto the specimen is of lower frequency and its spectrum is strongly decreasing with increasing frequency. Plastic deformation also emits signals of lower frequency that are of quasi-continuous character. Both signal types can be discriminated by filtering. As a consequence typical burst signal were received afterwards that can be correlated with crack propagation. Their spectra exhibit considerable portions up to about 1.9 MHz. The development in time of the burst signals points to the kind of crack propagation resp. its sequence of appearance. However, definitive comparison between load and acoustic emission should become possible, only when the disadvantages of the common load measurement can be reduced, e.g. by determining the load directly at the specimen instead of the hammer tup

  1. 49 CFR 177.810 - Vehicular tunnels.

    Science.gov (United States)

    2010-10-01

    ... through any urban vehicular tunnel used for mass transportation. [Amdt. 177-52, 46 FR 5316, Jan. 19, 1981... 49 Transportation 2 2010-10-01 2010-10-01 false Vehicular tunnels. 177.810 Section 177.810 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY...

  2. Towards a service centric contextualized vehicular cloud

    NARCIS (Netherlands)

    Hu, Xiping; Wang, Lei; Sheng, Zhengguo; TalebiFard, Peyman; Zhou, Li; Liu, Jia; Leung, Victor C.M.

    2014-01-01

    This paper proposes a service-centric contextualized vehicular (SCCV) cloud platform to facilitate the deployment and delivery of cloud-based mobile applications over vehicular networks. SCCV cloud employs a multi-tier architecture that consists of the network, mobile device, and cloud tiers. Based

  3. Vehicular Internet: Security & Privacy Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Kamran Zaidi

    2015-07-01

    Full Text Available The vehicular internet will drive the future of vehicular technology and intelligent transportation systems (ITS. Whether it is road safety, infotainment, or driver-less cars, the vehicular internet will lay the foundation for the future of road travel. Governments and companies are pursuing driver-less vehicles as they are considered to be more reliable than humans and, therefore, safer. The vehicles today are not just a means of transportation but are also equipped with a wide range of sensors that provide valuable data. If vehicles are enabled to share data that they collect with other vehicles or authorities for decision-making and safer driving, they thereby form a vehicular network. However, there is a lot at stake in vehicular networks if they are compromised. With the stakes so high, it is imperative that the vehicular networks are secured and made resilient to any attack or attempt that may have serious consequences. The vehicular internet can also be the target of a cyber attack, which can be devastating. In this paper, the opportunities that the vehicular internet offers are presented and then various security and privacy aspects are discussed and some solutions are presented.

  4. The Vehicular Information Space Framework

    Science.gov (United States)

    Prinz, Vivian; Schlichter, Johann; Schweiger, Benno

    Vehicular networks are distributed, self-organizing and highly mobile ad hoc networks. They allow for providing drivers with up-to-the-minute information about their environment. Therefore, they are expected to be a decisive future enabler for enhancing driving comfort and safety. This article introduces the Vehicular Information Space framework (VIS). Vehicles running the VIS form a kind of distributed database. It enables them to provide information like existing hazards, parking spaces or traffic densities in a location aware and fully distributed manner. In addition, vehicles can retrieve, modify and delete these information items. The underlying algorithm is based on features derived from existing structured Peer-to-Peer algorithms and extended to suit the specific characteristics of highly mobile ad hoc networks. We present, implement and simulate the VIS using a motorway and an urban traffic environment. Simulation studies on VIS message occurrence show that the VIS implies reasonable traffic overhead. Also, overall VIS message traffic is independent from the number of information items provided.

  5. Real-Time Emulation of Nonstationary Channels in Safety-Relevant Vehicular Scenarios

    Directory of Open Access Journals (Sweden)

    Golsa Ghiaasi

    2018-01-01

    Full Text Available This paper proposes and discusses the architecture for a real-time vehicular channel emulator capable of reproducing the input/output behavior of nonstationary time-variant radio propagation channels in safety-relevant vehicular scenarios. The vehicular channel emulator architecture aims at a hardware implementation which requires minimal hardware complexity for emulating channels with the varying delay-Doppler characteristics of safety-relevant vehicular scenarios. The varying delay-Doppler characteristics require real-time updates to the multipath propagation model for each local stationarity region. The vehicular channel emulator is used for benchmarking the packet error performance of commercial off-the-shelf (COTS vehicular IEEE 802.11p modems and a fully software-defined radio-based IEEE 802.11p modem stack. The packet error ratio (PER estimated from temporal averaging over a single virtual drive and the packet error probability (PEP estimated from ensemble averaging over repeated virtual drives are evaluated and compared for the same vehicular scenario. The proposed architecture is realized as a virtual instrument on National Instruments™ LabVIEW. The National Instrument universal software radio peripheral with reconfigurable input-output (USRP-Rio 2953R is used as the software-defined radio platform for implementation; however, the results and considerations reported are of general purpose and can be applied to other platforms. Finally, we discuss the PER performance of the modem for two categories of vehicular channel models: a vehicular nonstationary channel model derived for urban single lane street crossing scenario of the DRIVEWAY’09 measurement campaign and the stationary ETSI models.

  6. Field Measurements of PCB emissions from Building Surfaces Using a New Portable Emission Test Cell

    DEFF Research Database (Denmark)

    Lyng, Nadja; Haven, Rune; Gunnarsen, Lars Bo

    2016-01-01

    The purpose of the study was to measure PCB-emission rates from indoor surfaces on-site in contaminated buildings using a newly developed portable emission test cell. Emission rates were measured from six different surfaces; three untreated surfaces and three remediated surfaces in a contaminated...

  7. Beaconing Performance in IEEE 802.11p Vehicular Networks: the Effect of Radio Channel Congestion

    OpenAIRE

    Librino, Francesco; Renda, Maria Elena; Santi, Paolo

    2013-01-01

    In this paper, we study the performance of the beaconing mechanism underlying active safety vehicular applications in presence of different levels of channel congestion. The importance of this study lies in the fact that channel congestion is considered a major factor influencing communication performance in vehicular networks, and that ours is the first investigation of the effects of congestion based on extensive, real-world measurements. The results of our study reveal that congestion has ...

  8. The photo-oxidation of automobile emissions: measurements of the transformation products and their mutagenic activity

    Science.gov (United States)

    Kleindienst, Tadeusz E.; Smith, David F.; Hudgens, Edward E.; Snow, Richard F.; Perry, Erica; Claxton, Larry D.; Bufalini, Joseph J.; Black, Francis M.; Cupitt, Larry T.

    Dilute mixtures of automobile emissions (comprising 50% exhaust and 50% surrogate evaporative emissions) were irradiated in a 22.7 m 3 smog chamber and tested for mutagenic activity by using a variant of the Ames test. The exhaust was taken from a single vehicle, a 1977 Ford Mustang equipped with a catalytic converter. Irradiated and nonirradiated gas-phase emissions were used in exposures of the bacteria, Salmonella typhimurium, strains TA100 and TA98. A single set of vehicular operating conditions was used to perform multiple exposures. The mutagenic activities of extracts from the particulate phase were also measured with the standard plate incorporation assay. (In most experiments only direct-acting mutagenic compounds were measured.) The gas-phase data for TA100 and TA98 showed increased activity for the irradiated emissions when compared to the nonirradiated mixture, which exhibited negligible activity with respect to the control values. The particulate phase for both the irradiated and nonirradiated mixtures showed negligible activity when results were compared to the control values for both strains. However, the experimental conditions limited the amount of extractable mass which could be collected in the particulate phase. The measured activities from the gas phase and particulate phase were converted to the number of revertants per cubic meter of effluent (i.e. the mutagenic density) to compare the contributions of each of these phases to the total mutagenic activity for each strain. Under the experimental conditions of this study, the mutagenic density of the gas-phase component of the irradiated mixture contributed approximately two orders of magnitude more of the total TA100 activity than did the particulate phase. For TA98 the gas-phase component contributed approximately one order of magnitude more. However, caution must be exercised in extrapolating these results to urban atmospheres heavily impacted by automotive emissions, because the bacterial

  9. Measurement of fugitive emissions from gas processing plants in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, A. [Alberta Research Council, Edmonton, AB (Canada)

    2004-07-01

    This paper presents a new gas visualization camera created to detect leaks. An outline of the device's projected entry into the oil and gas industry was provided, and included: a demonstration of Differential Absorption Light Detection and Ranging (DIAL) and leak cameras to measure and reduce fugitive emissions; a comparison of DIAL measured emissions with estimated emissions; and a review of methods to measure particulate emissions. In addition, a background of gas leak visualisation technology was presented along with an an overview of DIAL and its results from sour gas plants. The results of a survey conducted in 2003 were presented, including leaks identified and repaired as well as a follow up leak survey. An analysis of pre and post-repair hydrocarbon emissions from the Deepcut area revealed a 60 per cent reduction with savings of $140,000 as well as additional savings from reduced carbon emissions. A similar survey conducted in another plant measured emissions from condensate tanks before and after cooler installation as well as from surrounding well sites, quantifying an 80 per cent reduction in methane emissions. Tasks identified for future research concerned particulate emissions and the development of Lidar methods which can currently identify particulates, but are not yet able to quantify them. Other tasks included a complete DIAL data workup and reporting; the quantification of both methane and carbon emissions reduction at a sour gas plant; a comparison of measured emissions with methods that estimate fugitives; and a complete review of particulate measurements. tabs, figs.

  10. Comparative use of different emission measurement approaches to determine methane emissions from a biogas plant

    DEFF Research Database (Denmark)

    Reinelt, Torsten; Delre, Antonio; Westerkamp, Tanja

    2017-01-01

    (corresponding to a methane loss of 0.6 and 2.1%) from team to team, depending on the number of measured emission points, operational state during the measurements and the measurement method applied. Taking the operational conditions into account, the deviation between different approaches and teams could......A sustainable anaerobic biowaste treatment has to mitigate methane emissions from the entire biogas production chain, but the exact quantification of these emissions remains a challenge. This study presents a comparative measurement campaign carried out with on-site and ground-based remote sensing...... measurement approaches conducted by six measuring teams at a Swedish biowaste treatment plant. The measured emissions showed high variations, amongst others caused by different periods of measurement performance in connection with varying operational states of the plant. The overall methane emissions measured...

  11. Measurement and prediction of enteric methane emission

    Science.gov (United States)

    Sejian, Veerasamy; Lal, Rattan; Lakritz, Jeffrey; Ezeji, Thaddeus

    2011-01-01

    The greenhouse gas (GHG) emissions from the agricultural sector account for about 25.5% of total global anthropogenic emission. While CO2 receives the most attention as a factor relative to global warming, CH4, N2O and chlorofluorocarbons (CFCs) also cause significant radiative forcing. With the relative global warming potential of 25 compared with CO2, CH4 is one of the most important GHGs. This article reviews the prediction models, estimation methodology and strategies for reducing enteric CH4 emissions. Emission of CH4 in ruminants differs among developed and developing countries, depending on factors like animal species, breed, pH of rumen fluid, ratio of acetate:propionate, methanogen population, composition of diet and amount of concentrate fed. Among the ruminant animals, cattle contribute the most towards the greenhouse effect through methane emission followed by sheep, goats and buffalos, respectively. The estimated CH4 emission rate per cattle, buffaloe, sheep and goat in developed countries are 150.7, 137, 21.9 and 13.7 (g/animal/day) respectively. However, the estimated rates in developing countries are significantly lower at 95.9 and 13.7 (g/animal/day) per cattle and sheep, respectively. There exists a strong interest in developing new and improving the existing CH4 prediction models to identify mitigation strategies for reducing the overall CH4 emissions. A synthesis of the available literature suggests that the mechanistic models are superior to empirical models in accurately predicting the CH4 emission from dairy farms. The latest development in prediction model is the integrated farm system model which is a process-based whole-farm simulation technique. Several techniques are used to quantify enteric CH4 emissions starting from whole animal chambers to sulfur hexafluoride (SF6) tracer techniques. The latest technology developed to estimate CH4 more accurately is the micrometeorological mass difference technique. Because the conditions under which

  12. [Measurement model of carbon emission from forest fire: a review].

    Science.gov (United States)

    Hu, Hai-Qing; Wei, Shu-Jing; Jin, Sen; Sun, Long

    2012-05-01

    Forest fire is the main disturbance factor for forest ecosystem, and an important pathway of the decrease of vegetation- and soil carbon storage. Large amount of carbonaceous gases in forest fire can release into atmosphere, giving remarkable impacts on the atmospheric carbon balance and global climate change. To scientifically and effectively measure the carbonaceous gases emission from forest fire is of importance in understanding the significance of forest fire in the carbon balance and climate change. This paper reviewed the research progress in the measurement model of carbon emission from forest fire, which covered three critical issues, i. e., measurement methods of forest fire-induced total carbon emission and carbonaceous gases emission, affecting factors and measurement parameters of measurement model, and cause analysis of the uncertainty in the measurement of the carbon emissions. Three path selections to improve the quantitative measurement of the carbon emissions were proposed, i. e., using high resolution remote sensing data and improving algorithm and estimation accuracy of burned area in combining with effective fuel measurement model to improve the accuracy of the estimated fuel load, using high resolution remote sensing images combined with indoor controlled environment experiments, field measurements, and field ground surveys to determine the combustion efficiency, and combining indoor controlled environment experiments with field air sampling to determine the emission factors and emission ratio.

  13. Comparative use of different emission measurement approaches to determine methane emissions from a biogas plant.

    Science.gov (United States)

    Reinelt, Torsten; Delre, Antonio; Westerkamp, Tanja; Holmgren, Magnus A; Liebetrau, Jan; Scheutz, Charlotte

    2017-10-01

    A sustainable anaerobic biowaste treatment has to mitigate methane emissions from the entire biogas production chain, but the exact quantification of these emissions remains a challenge. This study presents a comparative measurement campaign carried out with on-site and ground-based remote sensing measurement approaches conducted by six measuring teams at a Swedish biowaste treatment plant. The measured emissions showed high variations, amongst others caused by different periods of measurement performance in connection with varying operational states of the plant. The overall methane emissions measured by ground-based remote sensing varied from 5 to 25kgh -1 (corresponding to a methane loss of 0.6-3.0% of upgraded methane produced), depending on operating conditions and the measurement method applied. Overall methane emissions measured by the on-site measuring approaches varied between 5 and 17kgh -1 (corresponding to a methane loss of 0.6 and 2.1%) from team to team, depending on the number of measured emission points, operational state during the measurements and the measurement method applied. Taking the operational conditions into account, the deviation between different approaches and teams could be explained, in that the two largest methane-emitting sources, contributing about 90% of the entire site's emissions, were found to be the open digestate storage tank and a pressure release valve on the compressor station. Copyright © 2017. Published by Elsevier Ltd.

  14. [Investigation of emission characteristics for light duty vehicles with a portable emission measurement system].

    Science.gov (United States)

    Wang, Hai-Kun; Fu, Li-Xin; Zhou, Yu; Lin, Xin; Chen, Ai-Zhong; Ge, Wei-hu; Du, Xuan

    2008-10-01

    Emission from 7 typical light-duty vehicles under actual driving conditions was monitored using a portable emission measurement system to gather data for characterization of the real world vehicle emission in Shenzhen, including the effects of driving modes on vehicle emission, comparison of fuel consumption based emission factors (g x L(-1) with mileage based emission factors (g x km(-1)), and the average emission factors of the monitored vehicles. The acceleration and deceleration modes accounted for 66.7% of total travel time, 80.3% of traveling distance and 74.6%-79.2% of vehicle emission; the acceleration mode contributed more than other driving modes. The fuel based emission factors were less dependent on the driving speed; they may be utilized in building macro-scale vehicle emission inventory with smaller sensitivity to the vehicle driving conditions. The effect of vehicle technology on vehicle emission was significant; the emission factors of CO, HC and NO(x) of carbureted vehicles were 19.9-20.5, 5.6-26.1 and 1.8-2.0 times the more advanced vehicles of Euro II, respectively. Using the ECE + EUDC driving cycle would not produce the desired real-world emission rates of light duty vehicles in a typical Chinese city.

  15. Methane Emission Estimates from Landfills Obtained with Dynamic Plume Measurements

    International Nuclear Information System (INIS)

    Hensen, A.; Scharff, H.

    2001-01-01

    Methane emissions from 3 different landfills in the Netherlands were estimated using a mobile Tuneable Diode Laser system (TDL). The methane concentration in the cross section of the plume is measured downwind of the source on a transect perpendicular to the wind direction. A gaussian plume model was used to simulate the concentration levels at the transect. The emission from the source is calculated from the measured and modelled concentration levels.Calibration of the plume dispersion model is done using a tracer (N 2 O) that is released from the landfill and measured simultaneously with the TDL system. The emission estimates for the different locations ranged from 3.6 to 16 m 3 ha -1 hr -1 for the different sites. The emission levels were compared to emission estimates based on the landfill gas production models. This comparison suggests oxidation rates that are up to 50% in spring and negligible in November. At one of the three sites measurements were performed in campaigns in 3 consecutive years. Comparison of the emission levels in the first and second year showed a reduction of the methane emission of about 50% due to implementation of a gas extraction system. From the second to the third year emissions increased by a factor of 4 due to new land filling. Furthermore measurements were performed in winter when oxidation efficiency was reduced. This paper describes the measurement technique used, and discusses the results of the experimental sessions that were performed

  16. Magnitude and variation of traffic air pollution as measured by CO in ...

    African Journals Online (AJOL)

    Bernt Lindtjørn

    by CO in the City of Addis Ababa, Ethiopia ... PM10 and. Carbon Monoxide (CO) measurements along the roadsides ... (USA) was about 70% of the total CO emissions (11), whereas ..... restrict the ventilation of the vehicular emission. The low ...

  17. Rocket-borne EUV-visible emission measurements

    International Nuclear Information System (INIS)

    Schmidtke, G.; Baker, K.D.; Stasek, G.

    1982-01-01

    Two rocket-borne experiments for measuring EUV atmospheric emissions have been conducted. The first measured emissions at 391.4 nm and 557.7 nm, and the second measured emissions in the range from 50 to 650 nm. Height profiles of selected auroral emissions from atomic oxygen at 130.4 nm (exhibiting resonant radiation diffusion) and from atomic oxygen at 557.7 nm, and from neutral and ionized molecular nitrogen are shown. Some details of the recorded spectra are given. In the shorter wavelength regions, emissions from atomic oxygen and nitrogen dominate. Over 140 nm, Lyman-Birge-Hopfield bands, second positive bands and Vegard-Kaplan bands of molecular nitrogen contribute most strongly except for some atomic lines. The Lyman-Birge-Hopfield bands of molecular nitrogen are relatively weak during the auroral arc as compared to the diffuse aurora

  18. Location-based Forwarding in Vehicular Networks

    NARCIS (Netherlands)

    Klein Wolterink, W.

    2013-01-01

    In this thesis we focus on location-based message forwarding in vehicular networks to support intelligent transportation systems (ITSs). ITSs are transport systems that utilise information and communication technologies to increase their level of automation, in this way levering the performance of

  19. Secure Communication in Vehicular Networks - PRESERVE Demo

    NARCIS (Netherlands)

    Lagana, M.; Feiri, Michael; Sall, M.; Lange, M.; Tomatis, A.; Papadimitratos, P.

    2012-01-01

    Security and privacy are fundamental prerequisites for the deployment of vehicular communications. The near-deployment status of Safety Applications for Intelligent Transport Systems (ITS) calls for strong evidence on the applicability of proposed research solutions, notably close-to-reality

  20. 2012 IEEE Vehicular Networking Conference (VNC)

    NARCIS (Netherlands)

    Altintas, Onur; Chen, Wai; Heijenk, Geert; Oh, Hyun Seo; Chung, Jong-Moon; Dressler, Falko; Kargl, Frank; Pau, Giovanni; Schoch, Elmar

    2012-01-01

    On behalf of the Organizing Committee, we would like to welcome you to the fourth edition of the IEEE Vehicular Networking Conference in Seoul, Korea. IEEE VNC is a unique conference sponsored by both IEEE Communications Society and Intelligent Transportation Systems Society. It brings together

  1. Privacy-Preserving Security for Vehicular Communications

    Science.gov (United States)

    Weerasinghe, Hesiri Dhammika

    2011-01-01

    Because of the large number of deaths, severe injuries and huge financial loss due to auto accidents and poor traffic management, road safety and traffic management have become very important areas of interest among research community. As a result, Vehicular Ad-hoc Network (VANET) becomes a promising technology to improve road safety and quality…

  2. Air Monitoring, Measuring, and Emissions Research

    Science.gov (United States)

    Measurement research is advancing the ability to determine the composition of sources of air pollution, conduct exposure assessments, improve monitoring capabilities and support public health research.

  3. Imperiling urban environment through varying air pollution rein in measures and mass transit policies - a case study of Lahore

    International Nuclear Information System (INIS)

    Aziz, A.

    2015-01-01

    Gargantuan expansion of big cities has increased motor vehicular tremendously. Lahore, a primitive green city is now gripped with swelling motor vehicular air pollution. Mass public transport, a back bone of city transportation network, due to erroneous running significantly contributes toward motor vehicular air pollution. Policy initiatives of the Government to curb motor vehicular air pollution are merely focused upon reduction of air pollution at source by the use of technology and clean fuel programmes. The policies for introduction of mass transit remained imprecise which lead to rise in transportation demand and increase in surfeit emission; Half-baked policies normally stem out to get political popularity which imperils urban environment. The paper highlights inconsistent policy measures and unsound air pollution control strategies adopted in big cities of Pakistan. Furthermore it gives guidance for sustainable mass transit policy measures. (author)

  4. Effect of vehicular traffic, remote sources and new particle formation on the activation properties of cloud condensation nuclei in the megacity of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    C. E. Souto-Oliveira

    2016-11-01

    Full Text Available Atmospheric aerosol is the primary source of cloud condensation nuclei (CCN. The microphysics and chemical composition of aerosols can affect cloud development and the precipitation process. Among studies conducted in Latin America, only a handful have reported the impact of urban aerosol on CCN activation parameters such as activation ratio (AR and activation diameter (Dact. With over 20 million inhabitants, the Metropolitan Area of São Paulo (MASP is the largest megacity in South America. To our knowledge, this is the first study to assess the impact that remote sources and new particle formation (NPF events have on CCN activation properties in a South American megacity. The measurements were conducted in the MASP between August and September 2014. We measured the CCN within the 0.2–1.0 % range of supersaturation, together with particle number concentration (PNC and particle number distribution (PND, as well as trace-element concentrations and black carbon (BC. NPF events were identified on 35 % of the sampling days. Combining multivariate analysis in the form of positive matrix factorization (PMF with an aerosol profile from lidar and HYSPLIT model analyses allowed us to identify the main contribution of vehicular traffic on all days and sea salt and biomass burning from remote regions on 28 and 21 % of the sampling days, respectively. The AR and Dact parameters showed distinct patterns for daytime with intense vehicular traffic and nighttime periods. For example, CCN activation was lower during the daytime than during the nighttime periods, a pattern that was found to be associated mainly with local road-traffic emissions. A decrease in CCN activation was observed on the NPF event days, mainly due to high concentrations of particles with smaller diameters. We also found that aerosols from sea salt, industrial emissions, and biomass burning had minor effects on Dact. For example, nights with biomass burning and vehicular emissions

  5. Effect of vehicular traffic, remote sources and new particle formation on the activation properties of cloud condensation nuclei in the megacity of São Paulo, Brazil

    Science.gov (United States)

    Souto-Oliveira, Carlos Eduardo; de Fátima Andrade, Maria; Kumar, Prashant; Juliano da Silva Lopes, Fábio; Babinski, Marly; Landulfo, Eduardo

    2016-11-01

    Atmospheric aerosol is the primary source of cloud condensation nuclei (CCN). The microphysics and chemical composition of aerosols can affect cloud development and the precipitation process. Among studies conducted in Latin America, only a handful have reported the impact of urban aerosol on CCN activation parameters such as activation ratio (AR) and activation diameter (Dact). With over 20 million inhabitants, the Metropolitan Area of São Paulo (MASP) is the largest megacity in South America. To our knowledge, this is the first study to assess the impact that remote sources and new particle formation (NPF) events have on CCN activation properties in a South American megacity. The measurements were conducted in the MASP between August and September 2014. We measured the CCN within the 0.2-1.0 % range of supersaturation, together with particle number concentration (PNC) and particle number distribution (PND), as well as trace-element concentrations and black carbon (BC). NPF events were identified on 35 % of the sampling days. Combining multivariate analysis in the form of positive matrix factorization (PMF) with an aerosol profile from lidar and HYSPLIT model analyses allowed us to identify the main contribution of vehicular traffic on all days and sea salt and biomass burning from remote regions on 28 and 21 % of the sampling days, respectively. The AR and Dact parameters showed distinct patterns for daytime with intense vehicular traffic and nighttime periods. For example, CCN activation was lower during the daytime than during the nighttime periods, a pattern that was found to be associated mainly with local road-traffic emissions. A decrease in CCN activation was observed on the NPF event days, mainly due to high concentrations of particles with smaller diameters. We also found that aerosols from sea salt, industrial emissions, and biomass burning had minor effects on Dact. For example, nights with biomass burning and vehicular emissions showed slightly lower

  6. Superthermal electron distribution measurements from polarized electron cyclotron emission

    International Nuclear Information System (INIS)

    Luce, T.C.; Efthimion, P.C.; Fisch, N.J.

    1988-06-01

    Measurements of the superthermal electron distribution can be made by observing the polarized electron cyclotron emission. The emission is viewed along a constant magnetic field surface. This simplifies the resonance condition and gives a direct correlation between emission frequency and kinetic energy of the emitting electron. A transformation technique is formulated which determines the anisotropy of the distribution and number density of superthermals at each energy measured. The steady-state distribution during lower hybrid current drive and examples of the superthermal dynamics as the runaway conditions is varied are presented for discharges in the PLT tokamak. 15 refs., 8 figs

  7. Electron cyclotron emission measurement in Tore Supra

    International Nuclear Information System (INIS)

    Javon, C.

    1991-06-01

    Electron cyclotron radiation from Tore-Supra is measured with Michelson and Fabry-Perot interferometers. Calibration methods, essential for this diagnostic, are developed allowing the determination of electron temperature in the plasma. In particular the feasibility of Fabry-Perot interferometer calibration by an original method is demonstrated. A simulation code is developed for modelling non-thermal electron population in these discharges using measurements in non-inductive current generation regime [fr

  8. Fast Plasma Potential Measurements Using an Emissive Probe

    Science.gov (United States)

    Ready, Amanda; Clark, Michael; Endrizzi, Douglass; Forest, Cary; Peterson, Ethan

    2017-10-01

    A heated emissive probe was developed for making direct plasma potential (Vp) measurements in rapidly fluctuating plasmas. Previous experiments on the Big Red Ball (BRB) were hindered by sudden potential drops, making Langmuir measurements of the plasma potential difficult. DC heating of a tungsten filament to emission allowed for fast (4 MHz) floating potential measurements that closely matched Vp. Two BRB experiments currently use the emissive probe. The investigation of unmagnetized, collisionless shocks used plasma potential measurements to study the sub-structure of strong plasma shocks. A separate investigation of emulated magnetospheres in laboratory plasmas used the plasma potential to map the equilibria and instabilities in the electric field of such structures. Results showing electric field measurements and comparison with cold Langmuir measurements will be presented. Future plans for probe modifications and applications to other experiments on the BRB will also be shown.

  9. Measurements of fusion product emission profiles in tokamaks

    International Nuclear Information System (INIS)

    Strachan, J.D.; Heidbrink, W.W.; Hendel, H.W.; Lovberg, J.; Murphy, T.J.; Nieschmidt, E.B.; Tait, G.D.; Zweben, S.J.

    1986-11-01

    The techniques and results of fusion product emission profile measurements are reviewed. While neutron source strength profile measurements have been attempted by several methods, neutron scattering is a limitation to the results. Profile measurements using charged fusion products have recently provided an alternative since collimation is much easier for the charged particles

  10. Micrometeorological methods for measurements of mercury emissions over contaminated soils

    International Nuclear Information System (INIS)

    Kim, K.H.; Lindberg, S.E.; Hanson, P.J.; Owens, J.; Myers, T.P.

    1993-01-01

    As part of a larger study involving development and application of field and laboratory methods (micrometeorological, dynamic enclosure chamber, and controlled laboratory chamber methods) to measure the air/surface exchange of Hg vapor, we performed a series of preliminary measurements over contaminated soils. From March--April 1993, we used the modified Bowen ratio (MBR) method to measure emission rates of mercury over a floodplain contaminated with mercury near Oak Ridge, TN. The mercury emission rates measured from contaminated EFPC soils using the MBR method during early spring show that (1) in all cases, the contaminated soils acted as a source of mercury to the atmosphere with source strengths ranging from 17 to 160 ng m -2 h -1 ; and (2) the strengths of mercury emissions can be greatly influenced by the combined effects of surface soil temperature, residence time of air masses over the source area, and turbulence conditions. The mercury fluxes measured in a controlled flow chamber indicate that contaminated soils can exhibit up to an order of magnitude higher emission rates of Hg under conditions of elevated soil temperature, soil structure disturbance, and high turbulence. Mercury emissions from contaminated soils exceeded emissions from background soils by one to two orders of magnitude

  11. Measurement of PCB emissions from building surfaces using a novel portable emission test cell

    DEFF Research Database (Denmark)

    Lyng, Nadja; Gunnarsen, Lars Bo; Andersen, Helle Vibeke

    2016-01-01

    Polychlorinated biphenyls (PCBs) were used in building materials like caulks and paints from 1930 e1970s and in some cases that caused elevated PCB concentrations in the indoor air at levels considered harmful to occupant health. PCBs are semivolatile organic compounds and capable of spreading from...... and there is a need to prioritise remediation measures on different materials. An inexpensive and portable emission test cell was developed to resemble indoor conditions in relation to the area specific ventilation rate. Emissions were measured using the test cell in the laboratory on freshly made PCB paint. Further......, the chamber was used for determining emissions from PCB-containing building materials in the field as well as remediated walls. The measurements showed that sorption of PCBs to chamber walls was insignificant after 2-4 days of exposure to the source. Over a period of two weeks emission rates did not change...

  12. Ellisoidal reflector for measuring otoacoustic emissions

    DEFF Research Database (Denmark)

    Epp, Bastian; Heiskanen, Vesa; Pulkki, Ville Topias

    2016-01-01

    ear canal. This study presents the design and evaluation of a truncated prolate ellipsoidal reflector in combination with a large-diaphragm low-noise microphone to measure OAEs in the open ear canal of human listeners. The reflector was designed to gain information about BM processing at low...

  13. Gamma-ray emission profile measurements during JET ICRH discharges

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, O N; Marcus, F B; Sadler, G; Van Belle, P [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Howarth, P J.A. [Birmingham Univ. (United Kingdom); Adams, J M; Bond, D S [UKAEA Harwell Lab. (United Kingdom). Energy Technology Div.

    1994-07-01

    Gamma-ray emission from plasma-impurity reactions caused by minority ICRH accelerating fuel ions to MeV energies has been measured using the JET neutron profile monitor. A successful data analysis technique has been used to isolate the RF-induced gamma-ray emission that was detected, enabling profiles of gamma-ray emission to be obtained. The 2-d gamma-ray emission profiles show that virtually all the radiation originates from the low field side of the RF resonance layer, as expected from RF-induced pitch angle diffusion. The emission profiles indicate the presence of a small population of resonant {sup 3}He ions that possess orbits lying near the passing-trapped boundary. 6 refs., 4 figs.

  14. Diesel bus emissions measured in a tunnel study.

    Science.gov (United States)

    Jamriska, Milan; Morawska, Lidia; Thomas, Steven; He, Congrong

    2004-12-15

    The emission factors of a bus fleet consisting of approximately 300 diesel-powered buses were measured in a tunnel study under well-controlled conditions during a 2-d monitoring campaign in Brisbane. Particle number and mass concentration levels of submicrometer particles and PM2.5 were monitored by SMPS and DustTrak instruments at the tunnel's entrance and exit, respectively. Correlation between DustTrak and TEOM response to diesel emissions was assessed, and the DustTrak results were recalculated into TEOM equivalent data. The mean value of the number and mass emission factors was (3.11+/-2.41) x 10(14) particles km(-1) for submicrometer particles and 583+/-451 mg km(-1) for PM2.5 (DustTrak), respectively. TEOM PM2.5 equivalent emission factor was 267+/-207 mg km(-1). The results are in good agreement with the emission factors determined from steady-state dynamometer testing of 12 buses from the same Brisbane City bus fleet. The results indicate that when carefully designed, both approaches, the dynamometer and on-road studies, can provide comparable results, applicable for the assessment of the effect of traffic emissions on airborne particle pollution. A brief overview of emission factors determined from other on-road and dynamometer studies reported in the literature as well as with the regulatory values used for the vehicle emission inventory assessment is presented and compared with the results obtained in this study.

  15. Measuring Carbon Emissions of Pavement Construction in China

    Directory of Open Access Journals (Sweden)

    Youliang Huang

    2016-07-01

    Full Text Available While various methodologies for quantifying carbon emissions of pavement construction are developed worldwide, adopting and promoting the existing tools to China’s market is found fairly challenging due to institutional constraints. Therefore, the objectives of this study are to propose a methodology for measuring carbon emissions of pavement construction compatible with the fixed pricing systems prevalent in China; and develop an automatic tool for carbon estimations. The total carbon emissions are measured by aggregating emissions of energy consumption and materials used along with four stages, namely material manufacture, transportation, construction, and disposal. A set of composite carbon emission factors for energy and materials was calculated based on existing emission factors with the consideration of the boundaries concerned. The quantity of energy and materials used in pavement construction are obtained through bills of quantity and the fixed price system. The database of the emission factors for energy and materials was embedded into a C# based tool, and validated in a real case.

  16. New spectrometric measurement of atmospheric 60 micron emission

    International Nuclear Information System (INIS)

    Grossmann, K.U.; Barthol, P.; Frings, W.; Hennig, R.; Offermann, D.

    1982-01-01

    Absolute zenith intensities of the atomic oxygen fine structure emission at 63 microns measured above Kiruna, Sweden, on December 9, 1981, in the altitude range of 85 km to 237 km are discussed. The data obtained are compared with theoretical predictions for this emission. For the model intensity calculations, both local thermodynamic equilibrium (LTE) and non-LTE conditions are assumed. The significance of the 63-micron emission as a cooling mechanism of the thermosphere is briefly discussed. It is noted that the geomagnetic field before and during the flight was very quiet

  17. Measurement of neurotransmitters with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Laruelle, M.; Erritzoe, D.; Abi-Dargham, A.; Huang, Y. [Columbia Univ., Coll. of Physicians and Surgeons, Dept. of Psychiatry and Radiology, New York, NY (United States)

    2003-09-01

    Over the last decade several groups have provided evidence that PET and SPECT neuro-receptor imaging techniques might be applied to measure fluctuations of dopamine (DA) synaptic concentrations in the living human brain. It is generally believed that changes in the in vivo binding of radioligands following acute changes in transmitter levels are driven by binding competition. These techniques have been very successful in giving dynamic information regarding DA transmission. However, the development of similar techniques to study other neurotransmitter systems has proven difficult. This review paper first summarizes endogenous competition studies performed in animals and humans. The validity of the model underlying the interpretation of these data is critically assessed. Emerging data suggest that simple binding competition might not be the only phenomenon involved in these interactions; receptor trafficking might play an important role. A better understanding of the radioligand properties that determine sensitivity to endogenous molecules might facilitate the selective development of this type of radiotracer. (authors)

  18. Ellipsoidal reflector for measuring oto-acoustic emissions

    DEFF Research Database (Denmark)

    Epp, Bastian; Pulkki, Ville; Heiskanen, Vesa

    2014-01-01

    A truncated prolate ellipsoidal reflector having the ear canal of a listener at one focal point and large- diaphragm low-noise microphone at the other focal point is proposed for free-field recordings of oto-acoustic emissions. A prototype reflector consisting of three pieces is presented, which...... enables measuring the response of the system with different truncations. The response of the system is measured with a miniature loud- speaker, and proof-of-concept measurements of oto-acoustic emissions are presented. The effect of truncation and other physical parameters to the performance of the system...

  19. REVIEW ARTICLE: Emission measurement techniques for advanced powertrains

    Science.gov (United States)

    Adachi, Masayuki

    2000-10-01

    Recent developments in high-efficiency low-emission powertrains require the emission measurement technologies to be able to detect regulated and unregulated compounds with very high sensitivity and a fast response. For example, levels of a variety of nitrogen compounds and sulphur compounds should be analysed in real time in order to develop aftertreatment systems to decrease emission of NOx for the lean burning powertrains. Also, real-time information on the emission of particulate matter for the transient operation of diesel engines and direct injection gasoline engines is invaluable. The present paper reviews newly introduced instrumentation for such emission measurement that is demanded for the developments in advanced powertrain systems. They include Fourier transform infrared spectroscopy, mass spectrometry and fast response flame ionization detection. In addition, demands and applications of the fuel reformer developments for fuel cell electric vehicles are discussed. Besides the detection methodologies, sample handling techniques for the measurement of concentrations emitted from low emission vehicles for which the concentrations of the pollutants are significantly lower than the concentrations present in ambient air, are also described.

  20. A simple method for the measurement of reflective foil emissivity

    International Nuclear Information System (INIS)

    Ballico, M. J.; Ham, E. W. M. van der

    2013-01-01

    Reflective metal foil is widely used to reduce radiative heat transfer within the roof space of buildings. Such foils are typically mass-produced by vapor-deposition of a thin metallic coating onto a variety of substrates, ranging from plastic-coated reinforced paper to 'bubble-wrap'. Although the emissivity of such surfaces is almost negligible in the thermal infrared, typically less than 0.03, an insufficiently thick metal coating, or organic contamination of the surface, can significantly increase this value. To ensure that the quality of the installed insulation is satisfactory, Australian building code AS/NZS 4201.5:1994 requires a practical agreed method for measurement of the emissivity, and the standard ASTM-E408 is implied. Unfortunately this standard is not a 'primary method' and requires the use of specified expensive apparatus and calibrated reference materials. At NMIA we have developed a simple primary technique, based on an apparatus to thermally modulate the sample and record the apparent modulation in infra-red radiance with commercially available radiation thermometers. The method achieves an absolute accuracy in the emissivity of approximately 0.004 (k=2). This paper theoretically analyses the equivalence between the thermal emissivity measured in this manner, the effective thermal emissivity in application, and the apparent emissivity measured in accordance with ASTM-E408

  1. A simple method for the measurement of reflective foil emissivity

    Science.gov (United States)

    Ballico, M. J.; van der Ham, E. W. M.

    2013-09-01

    Reflective metal foil is widely used to reduce radiative heat transfer within the roof space of buildings. Such foils are typically mass-produced by vapor-deposition of a thin metallic coating onto a variety of substrates, ranging from plastic-coated reinforced paper to "bubble-wrap". Although the emissivity of such surfaces is almost negligible in the thermal infrared, typically less than 0.03, an insufficiently thick metal coating, or organic contamination of the surface, can significantly increase this value. To ensure that the quality of the installed insulation is satisfactory, Australian building code AS/NZS 4201.5:1994 requires a practical agreed method for measurement of the emissivity, and the standard ASTM-E408 is implied. Unfortunately this standard is not a "primary method" and requires the use of specified expensive apparatus and calibrated reference materials. At NMIA we have developed a simple primary technique, based on an apparatus to thermally modulate the sample and record the apparent modulation in infra-red radiance with commercially available radiation thermometers. The method achieves an absolute accuracy in the emissivity of approximately 0.004 (k=2). This paper theoretically analyses the equivalence between the thermal emissivity measured in this manner, the effective thermal emissivity in application, and the apparent emissivity measured in accordance with ASTM-E408.

  2. Gas-phase ammonia and water-soluble ions in particulate matter analysis in an urban vehicular tunnel.

    Science.gov (United States)

    Vieira-Filho, Marcelo S; Ito, Debora T; Pedrotti, Jairo J; Coelho, Lúcia H G; Fornaro, Adalgiza

    2016-10-01

    Ammonia is a key alkaline species, playing an important role by neutralizing atmospheric acidity and inorganic secondary aerosol production. On the other hand, the NH3/NH4 (+) increases the acidity and eutrophication in natural ecosystems, being NH3 classified as toxic atmospheric pollutant. The present study aims to give a better comprehension of the nitrogen content species distribution in fine and coarse particulate matter (PM2.5 and PM2.5-10) and to quantify ammonia vehicular emissions from an urban vehicular tunnel experiment in the metropolitan area of São Paulo (MASP). MASP is the largest megacity in South America, with over 20 million inhabitants spread over 2000 km(2) of urbanized area, which faces serious environmental problems. The PM2.5 and PM2.5-10 median mass concentrations were 44.5 and 66.6 μg m(-3), respectively, during weekdays. In the PM2.5, sulfate showed the highest concentration, 3.27 ± 1.76 μg m(-3), followed by ammonium, 1.14 ± 0.71 μg m(-3), and nitrate, 0.80 ± 0.52 μg m(-3). Likewise, the dominance (30 % of total PM2.5) of solid species, mainly the ammonium salts, NH4HSO4, (NH4)2SO4, and NH4NO3, resulted from simulation of inorganic species. The ISORROPIA simulation was relevant to show the importance of environment conditions for the ammonium phase distribution (solid/aqueous), which was solely aqueous at outside and almost entirely solid at inside tunnel. Regarding gaseous ammonia concentrations, the value measured inside the tunnel (46.5 ± 17.5 μg m(-3)) was 3-fold higher than that outside (15.2 ± 11.3 μg m(-3)). The NH3 vehicular emission factor (EF) estimated by carbon balance for urban tunnel was 44 ± 22 mg km(-1). From this EF value and considering the MASP traffic characteristics, it was possible to estimate more than 7 Gg NH3 year(-1) emissions that along with NOx are likely to cause rather serious problems to natural ecosystems in the region.

  3. Measurement of air pollutant emissions from Lome, Cotonou and Accra

    Science.gov (United States)

    Lee, James; Vaughan, Adam; Nelson, Bethany; Young, Stuart; Evans, Mathew; Morris, Eleanor; Ladkin, Russel

    2017-04-01

    High concentrations of airborne pollutants (e.g. the oxides of nitrogen, sulphur dioxide and carbon monoxide) in existing and evolving cities along the Guinea Coast cause respiratory diseases with potentially large costs to human health and the economic capacity of the local workforce. It is important to understand the rate of emission of such pollutants in order to model current and future air quality and provide guidance to the potential outcomes of air pollution abatement strategies. Often dated technologies and poor emission control strategies lead to substantial uncertainties in emission estimates calculated from vehicle and population number density statistics. The unreliable electrical supply in cities in the area has led to an increased reliance on small-scale diesel powered generators and these potentially present a significant source of emissions. The uncontrolled open incineration of waste adds a further very poorly constrained emission source within the cities. The DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa) project involved a field campaign which used highly instrumented aircraft capable of in situ measurements of a range of air pollutants. Seven flights using the UK British Antarctic Survey's Twin Otter aircraft specifically targeted air pollution emissions from cities in West Africa (4 x Accra, Ghana; 2 x Lome, Togo and 1 x Cotonou, Benin). Measurements of NO, NO2, SO2, CO, CH4 and CO2 were made at multiple altitudes upwind and downwind of the cities, with the mass balance technique used to calculate emission rates. These are then compared to the Emissions Database for Global Atmospheric Research (EDGAR) estimates. Ultimately the data will be used to inform on and potentially improve the emission estimates, which in turn should lead to better forecasting of air pollution in West African cities and help guide future air pollution abatement strategy.

  4. 47 CFR 2.1511 - Measurements of radiated emissions.

    Science.gov (United States)

    2010-10-01

    ... TREATY MATTERS; GENERAL RULES AND REGULATIONS FCC Procedure for Testing Class A, B and S Emergency... 243 MHz. Step (9) Compute the peak effective radiated power for the maximum level of each measured emission using the following formula: EC03JN91.001 where: dBmmeas is the measured receiver reading in dBm...

  5. MEASUREMENT OF FUGITIVE EMISSIONS AT REGION I LANDFILL

    Science.gov (United States)

    This report discusses a new measurement technology for characterizing emissions from large area sources. This work was funded by EPA's Monitoring and Measurement for the 21st Century Initiative, or 21M2. The site selected for demonstrating this technology is a superfund landfil...

  6. Safety message broadcast in vehicular networks

    CERN Document Server

    Bi, Yuanguo; Zhuang, Weihua; Zhao, Hai

    2017-01-01

    This book presents the current research on safety message dissemination in vehicular networks, covering medium access control and relay selection for multi-hop safety message broadcast. Along with an overall overview of the architecture, characteristics, and applications of vehicular networks, the authors discuss the challenging issues in the research on performance improvement for safety applications, and provide a comprehensive review of the research literature. A cross layer broadcast protocol is included to support efficient safety message broadcast by jointly considering geographical location, physical-layer channel condition, and moving velocity of vehicles in the highway scenario. To further support multi-hop safety message broadcast in a complex road layout, the authors propose an urban multi-hop broadcast protocol that utilizes a novel forwarding node selection scheme. Additionally, a busy tone based medium access control scheme is designed to provide strict priority to safety applications in vehicle...

  7. Opportunistic spectrum utilization in vehicular communication networks

    CERN Document Server

    Cheng, Nan

    2016-01-01

    This brief examines current research on improving Vehicular Networks (VANETs), examining spectrum scarcity due to the dramatic growth of mobile data traffic and the limited bandwidth of dedicated vehicular communication bands and the use of opportunistic spectrum bands to mitigate congestion. It reviews existing literature on the use of opportunistic spectrum bands for VANETs, including licensed and unlicensed spectrum bands and a variety of related technologies, such as cognitive radio, WiFi and device-to-device communications. Focused on analyzing spectrum characteristics, designing efficient spectrum exploitation schemes, and evaluating the date delivery performance when utilizing different opportunistic spectrum bands, the results presented in this brief provide valuable insights on improving the design and deployment of future VANETs.

  8. Measuring a fair and ambitious climate agreement using cumulative emissions

    International Nuclear Information System (INIS)

    Peters, Glen P; Andrew, Robbie M; Solomon, Susan; Friedlingstein, Pierre

    2015-01-01

    Policy makers have called for a ‘fair and ambitious’ global climate agreement. Scientific constraints, such as the allowable carbon emissions to avoid exceeding a 2 °C global warming limit with 66% probability, can help define ambitious approaches to climate targets. However, fairly sharing the mitigation challenge to meet a global target involves human values rather than just scientific facts. We develop a framework based on cumulative emissions of carbon dioxide to compare the consistency of countries’ current emission pledges to the ambition of keeping global temperatures below 2 °C, and, further, compare two alternative methods of sharing the remaining emission allowance. We focus on the recent pledges and other official statements of the EU, USA, and China. The EU and US pledges are close to a 2 °C level of ambition only if the remaining emission allowance is distributed based on current emission shares, which is unlikely to be viewed as ‘fair and ambitious’ by others who presently emit less. China’s stated emissions target also differs from measures of global fairness, owing to emissions that continue to grow into the 2020s. We find that, combined, the EU, US, and Chinese pledges leave little room for other countries to emit CO 2 if a 2 °C limit is the objective, essentially requiring all other countries to move towards per capita emissions 7 to 14 times lower than the EU, USA, or China by 2030. We argue that a fair and ambitious agreement for a 2 °C limit that would be globally inclusive and effective in the long term will require stronger mitigation than the goals currently proposed. Given such necessary and unprecedented mitigation and the current lack of availability of some key technologies, we suggest a new diplomatic effort directed at ensuring that the necessary technologies become available in the near future. (letter)

  9. METEV: Measurement Technologies for Emissions from Ethanol Fuelled Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Sandtroem-Dahl, Charlotte

    2009-11-15

    The interest of using alcohols, and especially ethanol, as vehicle fuel is high in Sweden. The advantages are many, such as; being renewable, the ethanol can be produced locally and it is easily mixed with gasoline. Alcohol fuels are considered to be a substantial part of the alternative fuel market, especially in Brazil, USA and Sweden. With this growing interest it is of most importance to investigate the emission performance of vehicles fuelled with alcohols. The focus in this study is on measurement and calculation of hydrocarbon emissions. The emission regulations in different countries have different ways to treat alcohol fuelled vehicles. When alcohols are used as blending components in gasoline, uncombusted alcohols from the fuel are emitted in the exhaust in various amounts. If a Flame Ionization Detector (FID) is used to measure hydrocarbons, the uncombusted alcohol will be included in the measurement. The alcohol is, per definition, however not a hydrocarbon (hydrocarbons contains only hydrogen and carbon). In the US regulations, the alcohol content is measured separately, and the FID measurement is adjusted for the alcohol part. This is not performed in the European regulations. The aim of this project is to highlight the need for a discussion regarding the methodology for measuring hydrocarbon and alcohol emissions from flexible fuelled vehicles operating on alcohol fuel blends.

  10. Comparison of exhaust emission on the basis of Real Driving Emissions measurements and simulations

    Directory of Open Access Journals (Sweden)

    Nowak Mateusz

    2017-01-01

    Full Text Available Designing of modern transport systems involves the need to meet a large number of requirements. The influence of designed road infrastructure on the environment is very wide and important. The most valid aspect in this case is the reduction of emissions of harmful compounds by increasing the fluency of vehicles flow and building collision free road intersections. But it should be started from establishing the initial emission level of harmful compounds. This paper presents a methodology for determining exhaust emissions from vehicles moving on the national road no. 50 in area of Zyrardow. Modern measuring tools such as the PEMS and the microscopic road simulation software, using the application to determine exhaust emissions, were used for this purpose.

  11. Cooperative vehicular communications in the drive-thru internet

    CERN Document Server

    Zhou, Haibo; Yu, Quan; Shen, Xuemin (Sherman)

    2015-01-01

    This brief presents a unified analytical framework for the evaluation of drive-thru Internet performance and accordingly proposes an optimal spatial access control management approach. A comprehensive overview and in-depth discussion of the research literature is included. It summarizes the main concepts and methods, and highlights future research directions. The brief also introduces a novel cooperative vehicular communication framework together with a delicate linear cluster formation scheme and low-delay content forwarding approach to provide a flexible and efficient vehicular content distribution in the drive-thru Internet. The presented medium access control and vehicular content distribution related research results in this brief provide useful insights for the design approach of Wi-Fi enabled vehicular communications and it motivates a new line of thinking for the performance enhancements of future vehicular networking. Advanced-level students, researchers and professionals interested in vehicular netw...

  12. High temperature spectral emissivity measurement using integral blackbody method

    Science.gov (United States)

    Pan, Yijie; Dong, Wei; Lin, Hong; Yuan, Zundong; Bloembergen, Pieter

    2016-10-01

    Spectral emissivity is a critical material's thermos-physical property for heat design and radiation thermometry. A prototype instrument based upon an integral blackbody method was developed to measure material's spectral emissivity above 1000 °. The system was implemented with an optimized commercial variable-high-temperature blackbody, a high speed linear actuator, a linear pyrometer, and an in-house designed synchronization circuit. A sample was placed in a crucible at the bottom of the blackbody furnace, by which the sample and the tube formed a simulated blackbody which had an effective total emissivity greater than 0.985. During the measurement, the sample was pushed to the end opening of the tube by a graphite rod which was actuated through a pneumatic cylinder. A linear pyrometer was used to monitor the brightness temperature of the sample surface through the measurement. The corresponding opto-converted voltage signal was fed and recorded by a digital multi-meter. A physical model was proposed to numerically evaluate the temperature drop along the process. Tube was discretized as several isothermal cylindrical rings, and the temperature profile of the tube was measurement. View factors between sample and rings were calculated and updated along the whole pushing process. The actual surface temperature of the sample at the end opening was obtained. Taking advantages of the above measured voltage profile and the calculated true temperature, spectral emissivity under this temperature point was calculated.

  13. Enabling content distribution in vehicular ad hoc networks

    CERN Document Server

    Luan, Tom H; Bai, Fan

    2014-01-01

    This SpringerBrief presents key enabling technologies and state-of-the-art research on delivering efficient content distribution services to fast moving vehicles. It describes recent research developments and proposals towards the efficient, resilient and scalable content distribution to vehicles through both infrastructure-based and infrastructure-less vehicular networks. The authors focus on the rich multimedia services provided by vehicular environment content distribution including vehicular communications and media playback, giving passengers many infotainment applications. Common problem

  14. Limits of predictability for large-scale urban vehicular mobility

    OpenAIRE

    Li, Yong; Jin, Depeng; Hui, Pan; Wang, Zhaocheng; Chen, Sheng

    2014-01-01

    Key challenges in vehicular transportation and communication systems are understanding vehicular mobility and utilizing mobility prediction, which are vital for both solving the congestion problem and helping to build efficient vehicular communication networking. Most of the existing works mainly focus on designing algorithms for mobility prediction and exploring utilization of these algorithms. However, the crucial questions of how much the mobility is predictable and how the mobility predic...

  15. FAST DIFFERENTIAL EMISSION MEASURE INVERSION OF SOLAR CORONAL DATA

    Energy Technology Data Exchange (ETDEWEB)

    Plowman, Joseph; Kankelborg, Charles; Martens, Petrus [Montana State University, Bozeman, MT 59717 (United States)

    2013-07-01

    We present a fast method for reconstructing differential emission measures (DEMs) using solar coronal data. The method consists of a fast, simple regularized inversion in conjunction with an iteration scheme for removal of residual negative emission measure. On average, it computes over 1000 DEMs s{sup -1} for a sample active region observed by the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory, and achieves reduced chi-squared of order unity with no negative emission in all but a few test cases. The high performance of this method is especially relevant in the context of AIA, which images of order one million solar pixels per second. This paper describes the method, analyzes its fidelity, compares its performance and results with other DEM methods, and applies it to an active region and loop observed by AIA and by the Extreme-ultraviolet Imaging Spectrometer on Hinode.

  16. Continuous measurements of N2O emissions from arable fields

    Science.gov (United States)

    Wallman, Magdalena; Lammirato, Carlo; Rütting, Tobias; Delin, Sofia; Weslien, Per; Klemedtsson, Leif

    2017-04-01

    Agriculture represents 59 % of the anthropogenic nitrous oxide (N2O) emissions, according to the IPCC (Ciais et al. 2013). N2O emissions are typically irregular and vary widely in time and space, which makes it difficult to get a good representation of the emissions (Henault et al. 2012), particularly if measurements have low frequency and/or cover only a short time period. Manual measurements are, for practical reasons, often short-term and low-frequent, or restricted to periods where emissions are expected to be high, e.g. after fertilizing. However, the nature of N2O emissions, being largely unpredictable, calls for continuous or near-continuous measurements over long time periods. So far, rather few long-term, high resolution measurements of N2O emissions from arable fields are reported; among them are Flessa et al. (2002) and Senapati et al. (2016). In this study, we have a two-year data set (2015-2017) with hourly measurements from ten automatic chambers, covering unfertilized controls as well as different nitrogen fertilizer treatments. Grain was produced on the field, and effects of tillage, harvest and other cropping measures were covered. What we can see from the experiment is that (a) the unfertilized control plots seem to follow the same emission pattern as the fertilized plots, at a level similar to the standard mineral fertilized plots (120 kg N ha-1 yr-1) and (b) freeze/thaw emissions are comparable in size to emissions after fertilizing. These two findings imply that the importance of fertilizing to the overall N2O emissions from arable soils may be smaller than previously expected. References: Ciais, P., C. Sabine, G. Bala, L. Bopp, V. Brovkin, J. Canadell et al. 2013: Carbon and Other Biogeochemical Cycles. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung et

  17. Probability Based Evaluation of Vehicular Bridge Load using Weigh-in-Motion Data

    Directory of Open Access Journals (Sweden)

    Widi Nugraha

    2016-02-01

    Full Text Available Load and Resistance Factored Design (LRFD method for designing bridge in Indonesia have been implemented for more than 25 years. LRFD method treating loads and strengths variables as random variables with specific safety factors for different loads and strengths variables type. The nominal loads, load factors, reduction factors, and other criteria for bridge design code can be determined to meet the reliability criteria. Statistical data of weigh-in-motion (WIM vehicular loads measurement in Northern Java highway, Cikampek - Pamanukan, West Java (2011, used in as statistical loads variable. A 25 m simple span bridge with reinforced concrete T-girder is used as a model for structural analysis due to WIM measured and nominal vehicular load based on RSNI T-02-2005, with applied bending moment of girder as the output. The distribution fitting result of applied bending moment due to WIM measured vehicular loads is lognormal. The maximum bending moment due to RSNI T-02-2005 nominal vehicular load is 842.45 kN-m and has probability of exceedance of 5x10-5. It can be concluded, for this study, that the bridge designed using RSNI T-02-2005 is safely designed, since it has reliability index, β of 5.02, higher than target reliability, β ranging from 3.50 or 3.72.

  18. Developments in Emission Measurements Using Lightweight Sensors and Samplers.

    Science.gov (United States)

    Lightweight emission measurement systems making use of miniaturized sensors and samplers have been developed for portable and aerial sampling for an array of pollutants. Shoebox-sized systems called “Kolibri”, weighing 3-5 kg, have been deployed on NASA-flown unmanned...

  19. Measurement of absolute bone blood flow by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nahmias, C.; Cockshott, W.P.; Garnett, E.S.; Belbeck, L.W.

    1986-03-01

    A method of measuring bone blood flow has been developed using /sup 18/F sodium fluoride and positron emission tomography. The blood flow levels are in line with those obtained experimentally from microsphere embolisation. This investigative method could be applied to elucidate a number of clinical questions involving bone perfusion.

  20. GHG emission mitigation measures and technologies in the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Tichy, M. [Energy Efficiency Center, Prague (Czech Republic)

    1996-12-31

    The paper presents a short overview of main results in two fields: projection of GHG emission from energy sector in the Czech Republic and assessment of technologies and options for GHG mitigation. The last part presents an overview of measures that were prepared for potential inclusion to the Czech Climate Change Action Plan.

  1. Accuracy of exhaust emission factor measurements on chassis dynamometer

    NARCIS (Netherlands)

    Joumard, R.; Laurikko, J.; Han, T.L.; Geivanidis, S.; Samaras, Z.; Merétei, T.; Devaux, P.; André, J.-M.; Cornelis, E.; Lacour, S.; Prati, M.V.; Vermeulen, R.; Zallinger, M.

    2009-01-01

    The influence of 20 parameters on the measurement of light-vehicle emission factors on chassis dynamometer based on driving patterns, vehicle-related parameters, vehicle sampling, and laboratory-related parameters, was studied. The results were based on literature synthesis, ≈ 2700 specific tests

  2. Thermal conductivity and emissivity measurements of uranium carbides

    International Nuclear Information System (INIS)

    Corradetti, S.; Manzolaro, M.; Andrighetto, A.; Zanonato, P.; Tusseau-Nenez, S.

    2015-01-01

    Highlights: • Thermal conductivity and emissivity measurements of uranium carbides were performed. • The tested materials are candidates as targets for radioactive ion beam production. • The results are correlated with the materials composition and microstructure. - Abstract: Thermal conductivity and emissivity measurements on different types of uranium carbide are presented, in the context of the ActiLab Work Package in ENSAR, a project within the 7th Framework Program of the European Commission. Two specific techniques were used to carry out the measurements, both taking place in a laboratory dedicated to the research and development of materials for the SPES (Selective Production of Exotic Species) target. In the case of thermal conductivity, estimation of the dependence of this property on temperature was obtained using the inverse parameter estimation method, taking as a reference temperature and emissivity measurements. Emissivity at different temperatures was obtained for several types of uranium carbide using a dual frequency infrared pyrometer. Differences between the analyzed materials are discussed according to their compositional and microstructural properties. The obtainment of this type of information can help to carefully design materials to be capable of working under extreme conditions in next-generation ISOL (Isotope Separation On-Line) facilities for the generation of radioactive ion beams.

  3. Objective Measure of Nasal Air Emission Using Nasal Accelerometry

    Science.gov (United States)

    Cler, Meredith J.; Lien, Yu-An, S.; Braden, Maia N.; Mittleman, Talia; Downing, Kerri; Stepp, Cara, E.

    2016-01-01

    Purpose: This article describes the development and initial validation of an objective measure of nasal air emission (NAE) using nasal accelerometry. Method: Nasal acceleration and nasal airflow signals were simultaneously recorded while an expert speech language pathologist modeled NAEs at a variety of severity levels. In addition, microphone and…

  4. MEASUREMENT OF FUGITIVE EMISSIONS AT A BIOREACTOR LANDFILL

    Science.gov (United States)

    This report focuses on three field campaigns performed in 2002 and 2003 to measure fugitive emissions at a bioreactor landfill in Louisville, KY, using an open-path Fourier transform infrared spectrometer. The study uses optical remote sensing-radial plume mapping. The horizontal...

  5. Results of measurements of emission from internal combustion engines

    International Nuclear Information System (INIS)

    Dimitrovski, Mile; Jovanovska, Vangelica

    1999-01-01

    A mathematical model for solving the emission from internal combustion engines on the cross roads are made. The exhausted pipes from vehicles are substituted with a pipe in a centre of the cross road. This model is proved with measurement made on vehicles in the city of Bitola (Macedonia). (Author)

  6. Virtual Instrument for Emissions Measurement of Internal Combustion Engines

    Science.gov (United States)

    Pérez, Armando; Montero, Gisela; Coronado, Marcos; García, Conrado; Pérez, Rubén

    2016-01-01

    The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM), and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user. PMID:27034893

  7. Virtual Instrument for Emissions Measurement of Internal Combustion Engines.

    Science.gov (United States)

    Pérez, Armando; Ramos, Rogelio; Montero, Gisela; Coronado, Marcos; García, Conrado; Pérez, Rubén

    2016-01-01

    The gases emissions measurement systems in internal combustion engines are strict and expensive nowadays. For this reason, a virtual instrument was developed to measure the combustion emissions from an internal combustion diesel engine, running with diesel-biodiesel mixtures. This software is called virtual instrument for emissions measurement (VIEM), and it was developed in the platform of LabVIEW 2010® virtual programming. VIEM works with sensors connected to a signal conditioning system, and a data acquisition system is used as interface for a computer in order to measure and monitor in real time the emissions of O2, NO, CO, SO2, and CO2 gases. This paper shows the results of the VIEM programming, the integrated circuits diagrams used for the signal conditioning of sensors, and the sensors characterization of O2, NO, CO, SO2, and CO2. VIEM is a low-cost instrument and is simple and easy to use. Besides, it is scalable, making it flexible and defined by the user.

  8. Measurement of brain pH with positron emission tomography

    International Nuclear Information System (INIS)

    Buxton, R.B.; Alpert, N.M.; Ackerman, R.H.; Wechsler, L.R.; Elmaleh, D.R.; Correia, J.A.

    1985-01-01

    With positron emission tomography (PET) it is now possible to measure local brain pH noninvasively in humans. The application of PET to the determination of pH is relatively new, so only a handful of papers on the subject have appeared in print. This chapter reviews the current strategies for measuring brain pH with PET, discuss methodological problems, and present initial results

  9. Measurement of liver volume by emission computed tomography

    International Nuclear Information System (INIS)

    Kan, M.K.; Hopkins, G.B.

    1979-01-01

    In 22 volunteers without clinical or laboratory evidence of liver disease, liver volume was determined using single-photon emission computed tomography (ECT). This technique provided excellent object contrast between the liver and its surroundings and permitted calculation of liver volume without geometric assumptions about the liver's configuration. Reproducibility of results was satisfactory, with a root-mean-square error of less than 6% between duplicate measurements in 15 individuals. The volume measurements were validated by the use of phantoms

  10. Acoustic emission measurements on type 316 stainless steel

    International Nuclear Information System (INIS)

    Palmer, I.G.; Holt, J.; Goddard, D.J.

    1976-01-01

    Acoustic emission measurements have been made on Type 316 stainless steel in the solution treated condition, as part of a feasibility study for the monitoring of fast reactor components. The work involved testing both plain tensile specimens and precracked compact tension specimens in the temperature range 20-200 deg C. At 20 deg C plastic deformation was a quiet process but ductile crack growth was accompanied by high amplitude emissions capable of detection on plant. At 200 deg C both plastic deformation and ductile crack growth were quiet

  11. Analysis and Measurement of NOx Emissions in Port Auxiliary Vessels

    Directory of Open Access Journals (Sweden)

    German de Melo Rodriguez

    2013-09-01

    Full Text Available This paper is made NOx pollution emitted by port auxiliary vessels, specifically by harbour tugs, due to its unique operating characteristics of operation, require a large propulsion power changes discontinuously, also possess some peculiar technical characteristics, large tonnage and high propulsive power, that differentiate them from other auxiliary vessels of the port. Taking into account all the above features, there are no studies of the NOx emission engines caused by different working regimes of power because engine manufacturers have not measured these emissions across the range of operating power, but usually we only report the pollution produced by its engines to a maximum continuous power.

  12. MASER: Measuring, Analysing, Simulating low frequency Radio Emissions.

    Science.gov (United States)

    Cecconi, B.; Le Sidaner, P.; Savalle, R.; Bonnin, X.; Zarka, P. M.; Louis, C.; Coffre, A.; Lamy, L.; Denis, L.; Griessmeier, J. M.; Faden, J.; Piker, C.; André, N.; Genot, V. N.; Erard, S.; King, T. A.; Mafi, J. N.; Sharlow, M.; Sky, J.; Demleitner, M.

    2017-12-01

    The MASER (Measuring, Analysing and Simulating Radio Emissions) project provides a comprehensive infrastructure dedicated to low frequency radio emissions (typically Radioastronomie de Nançay and the CDPP deep archive. These datasets include Cassini/RPWS, STEREO/Waves, WIND/Waves, Ulysses/URAP, ISEE3/SBH, Voyager/PRA, Nançay Decameter Array (Routine, NewRoutine, JunoN), RadioJove archive, swedish Viking mission, Interball/POLRAD... MASER also includes a Python software library for reading raw data.

  13. Standardization in dust emission measurement; Mesure des emissions de poussieres normalisation

    Energy Technology Data Exchange (ETDEWEB)

    Perret, R. [INERIS, 60 - Verneuil-en-Halatte, (France)

    1996-12-31

    The European Standardization Committee (CEN TC 264WG5) is developing a new reference method for measuring particulate emissions, suitable for concentrations inferior to 20 mg/m{sup 3} and especially for concentrations around 5 mg/m{sup 3}; the measuring method should be applicable to waste incinerator effluents and more generally to industrial effluents. Testing protocols and data analysis have been examined and repeatability and reproducibility issues are discussed

  14. Measurements of nitrous oxide emissions from vegetable production in China

    Science.gov (United States)

    Xiong, Zhengqin; Xie, Yingxin; Xing, Guangxi; Zhu, Zhaoliang; Butenhoff, Chris

    Nitrous oxide (N 2O) emissions resulting from Chinese vegetable production were measured. A site in suburban Nanjing (East coast; Jiangsu Province) was monitored from November 2001 to January 2003, in which five consecutive vegetable crops were sown. The crops consisted of radish, baby bok choy, lettuce, second planting of baby bok choy, and finally celery. Results suggested that N 2O emission events occur in pulses. The average N 2O-N flux for all five crops was 148±9 μg N m -2 h -1 and the average emission rate was 12±0.7 kg N ha -1. The average seasonal emission fluxes ranged from 37 μg N m -2 h -1 in the radish plot to 300 μg N m -2 h -1 in the celery plot. The celery field produced the greatest cumulative emission of 5.8 kg N ha -1 while the baby bok choy field had the lowest rate of 0.96-1.0 kg N ha -1. In total, 0.73% of applied fertilizer N was emitted as N 2O-N as a whole. The lettuce field had the largest emission factor of 2.2%. Results indicate that emissions from vegetable field are a potential source of national N 2O inventory. Temporal variation is much greater than spatial variation and the corresponding CV averaged 115% and 22%, respectively. Under the same total sampling quantity, increasing sampling frequency is more important than increasing spatial replicates.

  15. Time division multiple access for vehicular communications

    CERN Document Server

    Omar, Hassan Aboubakr

    2014-01-01

    This brief focuses on medium access control (MAC) in vehicular ad hoc networks (VANETs), and presents VeMAC, a novel MAC scheme based on distributed time division multiple access (TDMA) for VANETs. The performance of VeMAC is evaluated via mathematical analysis and computer simulations in comparison with other existing MAC protocols, including the IEEE 802.11p standard. This brief aims at proposing TDMA as a suitable MAC scheme for VANETs, which can support the quality-of-service requirements of high priority VANET applications.

  16. Electron bunchlength measurement from analysis of fluctuations in spontaneous emission

    International Nuclear Information System (INIS)

    Catravas, P.; Leemans, W.P.; Wurtele, J.S.; Zolotorev, M.S.; Babzien, M.; Ben-Zvi, I.; Segalov, Z.; Wang, X.; Yakimenko, V.

    1999-01-01

    A statistical analysis of fluctuations in the spontaneous emission of a single bunch of electrons is shown to provide a new bunchlength diagnostic. This concept, originally proposed by Zolotorev and Stupakov [1], is based on the fact that shot noise from a finite bunch has a correlation length defined by the bunchlength, and therefore has a spiky spectrum. Single shot spectra of wiggler spontaneous emission have been measured at 632 nm from 44 MeV single electron bunches of 1 - 5 ps. The scaling of the spectral fluctuations with frequency resolution and the scaling of the spectral intensity distribution with bunchlength are studied. Bunchlength was extracted in a single shot measurement. Agreement was obtained between the experiment and a theoretical model, and with independent time integrated measurements. copyright 1999 American Institute of Physics

  17. Electron cyclotron emission measurements at the stellarator TJ-K

    Energy Technology Data Exchange (ETDEWEB)

    Sichardt, Gabriel; Ramisch, Mirko [Institut fuer Grenzflaechenverfahrenstechnik und Plasmatechnologie, Universitaet Stuttgart (Germany); Koehn, Alf [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    2016-07-01

    Electron temperature (T{sub e}) measurements in the magnetised plasmas of the stellarator TJ-K are currently performed by means of Langmuir probes. The use of these probes is restricted to relatively low temperatures and the measurement of temperature profiles requires the acquisition of the local current-voltage characteristics which limits strongly the sampling rate. As an alternative, T{sub e} can be measured using the electron cyclotron emission (ECE) that is generated by the gyration of electrons in magnetised plasmas. Magnetic field gradients in the plasma lead to a spatial distribution of emission frequencies and thus the measured intensity at a given frequency can be related to its point of origin. The T{sub e} dependence of the intensity then leads to a temperature profile along the line of sight for Maxwellian velocity distributions. A diagnostic system for T{sub e} measurements using ECE is currently being set up at TJ-K. When non-thermal electrons are present the emission spectrum changes dramatically. Therefore, the ECE can also be used to investigate the contribution of fast electrons to previously observed toroidal net currents in TJ-K. Simulations are used to examine the role of electron drift orbits in generating these currents.

  18. Measurement of the deuterium Balmer series line emission on EAST

    Energy Technology Data Exchange (ETDEWEB)

    Wu, C. R.; Xu, Z.; Jin, Z.; Zhang, P. F. [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China); Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, Anhui 230031 (China); Huang, J., E-mail: juan.huang@ipp.ac.cn; Gao, W.; Gao, W.; Chang, J. F.; Xu, J. C.; Duan, Y. M.; Chen, Y. J.; Zhang, L.; Wu, Z. W.; Li, J. G. [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China); Hou, Y. M. [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China); School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2016-11-15

    Volume recombination plays an important role towards plasma detachment for magnetically confined fusion devices. High quantum number states of the Balmer series of deuterium are used to study recombination. On EAST (Experimental Advanced Superconducting Tokamak), two visible spectroscopic measurements are applied for the upper/lower divertor with 13 channels, respectively. Both systems are coupled with Princeton Instruments ProEM EMCCD 1024B camera: one is equipped on an Acton SP2750 spectrometer, which has a high spectral resolution ∼0.0049 nm with 2400 gr/mm grating to measure the D{sub α}(H{sub α}) spectral line and with 1200 gr/mm grating to measure deuterium molecular Fulcher band emissions and another is equipped on IsoPlane SCT320 using 600 gr/mm to measure high-n Balmer series emission lines, allowing us to study volume recombination on EAST and to obtain the related line averaged plasma parameters (T{sub e}, n{sub e}) during EAST detached phases. This paper will present the details of the measurements and the characteristics of deuterium Balmer series line emissions during density ramp-up L-mode USN plasma on EAST.

  19. The ranking of negative-cost emissions reduction measures

    International Nuclear Information System (INIS)

    Taylor, Simon

    2012-01-01

    A flaw has been identified in the calculation of the cost-effectiveness in marginal abatement cost curves (MACCs). The problem affects “negative-cost” emissions reduction measures—those that produce a return on investment. The resulting ranking sometimes favours measures that produce low emissions savings and is therefore unreliable. The issue is important because incorrect ranking means a potential failure to achieve the best-value outcome. A simple mathematical analysis shows that not only is the standard cost-effectiveness calculation inadequate for ranking negative-cost measures, but there is no possible replacement that satisfies reasonable requirements. Furthermore, the concept of negative cost-effectiveness is found to be unsound and its use should be avoided. Among other things, this means that MACCs are unsuitable for ranking negative-cost measures. As a result, MACCs produced by a range of organizations including UK government departments may need to be revised. An alternative partial ranking method has been devised by making use of Pareto optimization. The outcome can be presented as a stacked bar chart that indicates both the preferred ordering and the total emissions saving available for each measure without specifying a cost-effectiveness. - Highlights: ► Marginal abatement cost curves (MACCs) are used to rank emission reduction measures. ► There is a flaw in the standard ranking method for negative-cost measures. ► Negative values of cost-effectiveness (in £/tC or equivalent) are invalid. ► There may be errors in published MACCs. ► A method based on Pareto principles provides an alternative ranking method.

  20. Vehicular Traffic Optimization in VANETs: a Proposal for Nodes Re-routing and Congestion Reduction

    Directory of Open Access Journals (Sweden)

    Mauro Tropea

    2015-01-01

    Full Text Available Recently, vehicular networking has grown up in terms of interest and transmission capability, due to the possibility of exploiting the distributed communication paradigm in a mobile scenario, where moving nodes are represented by vehicles. In this paper, we focus our attention on the optimization of traffic flowing in a vehicular environment with vehicle-roadside capability. As shown in the next sections, the proposed idea exploits the information that is gathered by road-side units with the main aim of redirecting traffic flows (in terms of vehicles to less congested roads, with an overall system optimization, also in terms of Carbon Dioxide emissions reduction. A deep campaign of simulations has been carried out to give more effectiveness to our proposal.

  1. Evaluating measurements of carbon dioxide emissions using a precision source--A natural gas burner.

    Science.gov (United States)

    Bryant, Rodney; Bundy, Matthew; Zong, Ruowen

    2015-07-01

    A natural gas burner has been used as a precise and accurate source for generating large quantities of carbon dioxide (CO2) to evaluate emissions measurements at near-industrial scale. Two methods for determining carbon dioxide emissions from stationary sources are considered here: predicting emissions based on fuel consumption measurements-predicted emissions measurements, and direct measurement of emissions quantities in the flue gas-direct emissions measurements. Uncertainty for the predicted emissions measurement was estimated at less than 1%. Uncertainty estimates for the direct emissions measurement of carbon dioxide were on the order of ±4%. The relative difference between the direct emissions measurements and the predicted emissions measurements was within the range of the measurement uncertainty, therefore demonstrating good agreement. The study demonstrates how independent methods are used to validate source emissions measurements, while also demonstrating how a fire research facility can be used as a precision test-bed to evaluate and improve carbon dioxide emissions measurements from stationary sources. Fossil-fuel-consuming stationary sources such as electric power plants and industrial facilities account for more than half of the CO2 emissions in the United States. Therefore, accurate emissions measurements from these sources are critical for evaluating efforts to reduce greenhouse gas emissions. This study demonstrates how a surrogate for a stationary source, a fire research facility, can be used to evaluate the accuracy of measurements of CO2 emissions.

  2. Estimates of CO2 traffic emissions from mobile concentration measurements

    Science.gov (United States)

    Maness, H. L.; Thurlow, M. E.; McDonald, B. C.; Harley, R. A.

    2015-03-01

    We present data from a new mobile system intended to aid in the design of upcoming urban CO2-monitoring networks. Our collected data include GPS probe data, video-derived traffic density, and accurate CO2 concentration measurements. The method described here is economical, scalable, and self-contained, allowing for potential future deployment in locations without existing traffic infrastructure or vehicle fleet information. Using a test data set collected on California Highway 24 over a 2 week period, we observe that on-road CO2 concentrations are elevated by a factor of 2 in congestion compared to free-flow conditions. This result is found to be consistent with a model including vehicle-induced turbulence and standard engine physics. In contrast to surface concentrations, surface emissions are found to be relatively insensitive to congestion. We next use our model for CO2 concentration together with our data to independently derive vehicle emission rate parameters. Parameters scaling the leading four emission rate terms are found to be within 25% of those expected for a typical passenger car fleet, enabling us to derive instantaneous emission rates directly from our data that compare generally favorably to predictive models presented in the literature. The present results highlight the importance of high spatial and temporal resolution traffic data for interpreting on- and near-road concentration measurements. Future work will focus on transport and the integration of mobile platforms into existing stationary network designs.

  3. Mercury emission, control and measurement from coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Wei-Ping [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering; Western Kentucky Univ., Bowling Green, KY (United States). Inst. for Combustion Science and Environmental Technology; Cao, Yan [Western Kentucky Univ., Bowling Green, KY (United States). Inst. for Combustion Science and Environmental Technology; Zhang, Kai [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering

    2013-07-01

    Coal-fired electric power generation accounts for 65% of U.S. emissions of sulfur dioxide (SO2), 22% of nitrogen oxides (NOx), and 37% of mercury (Hg). The proposed Clear Air Interstate Rule (CAIR) and Clean Air Mercury Rule (CAMR) will attempt to regulate these emissions using a cap-and-trade program to replace a number of existing regulatory requirements that will impact this industry over the next decade. Mercury emissions remain the largest source that has not yet been efficiently controlled, in part because this is one of the most expensive to control. Mercury is a toxic, persistent pollutant that accumulates in the food chain. During the coal combustion process, when both sampling and accurate measurements are challenging, we know that mercury is present in three species: elemental, oxidized and particulate. There are three basic types of mercury measurement methods: Ontario Hydro Method, mercury continuous emission monitoring systems (CEMS) and sorbent-based monitoring. Particulate mercury is best captured by electrostatic precipitators (ESP). Oxidized mercury is best captured in wet scrubbers. Elemental mercury is the most difficult to capture, but selective catalytic reduction units (SCRs) are able to convert elemental mercury to oxidized mercury allowing it to be captured by wet flue gas desulfurization (FGD). This works well for eastern coals with high chlorine contents, but this does not work well on the Wyoming Powder River Basin (PRB) coals. However, no good explanation for its mechanism, correlations of chlorine content in coal with SCR performance, and impacts of higher chlorine content in coal on FGD re-emission are available. The combination of SCR and FGD affords more than an 80% reduction in mercury emissions in the case of high chlorine content coals. The mercury emission results from different coal ranks, boilers, and the air pollution control device (APCD) in power plant will be discussed. Based on this UAEPA new regulation, most power plants

  4. Local Optimization Strategies in Urban Vehicular Mobility.

    Directory of Open Access Journals (Sweden)

    Pierpaolo Mastroianni

    Full Text Available The comprehension of vehicular traffic in urban environments is crucial to achieve a good management of the complex processes arising from people collective motion. Even allowing for the great complexity of human beings, human behavior turns out to be subject to strong constraints--physical, environmental, social, economic--that induce the emergence of common patterns. The observation and understanding of those patterns is key to setup effective strategies to optimize the quality of life in cities while not frustrating the natural need for mobility. In this paper we focus on vehicular mobility with the aim to reveal the underlying patterns and uncover the human strategies determining them. To this end we analyze a large dataset of GPS vehicles tracks collected in the Rome (Italy district during a month. We demonstrate the existence of a local optimization of travel times that vehicle drivers perform while choosing their journey. This finding is mirrored by two additional important facts, i.e., the observation that the average vehicle velocity increases by increasing the travel length and the emergence of a universal scaling law for the distribution of travel times at fixed traveled length. A simple modeling scheme confirms this scenario opening the way to further predictions.

  5. Covariation of binaural, concurrently-measured spontaneous otoacoustic emissions.

    Science.gov (United States)

    Penner, M J; Brauth, S E; Jastreboff, P J

    1994-03-01

    Simultaneous recordings of binaural spontaneous otoacoustic emissions (SOAEs) were made for 2 female subjects. For SOAEs below about 3.6 kHz measured within a testing session, the frequencies of nearby monaural and binaural SOAEs tended to move in tandem, whereas widely separated SOAEs did not. Across many testing sessions spanning a menstrual cycle, all monaural and binaural SOAE frequencies shifted in tandem. Possible mechanisms consistent with these results are discussed.

  6. Optimization of Vehicular Trajectories under Gaussian Noise Disturbances

    Directory of Open Access Journals (Sweden)

    Joan Garcia-Haro

    2012-12-01

    Full Text Available Nowadays, research on Vehicular Technology aims at automating every single mechanical element of vehicles, in order to increase passengers’ safety, reduce human driving intervention and provide entertainment services on board. Automatic trajectory tracing for vehicles under especially risky circumstances is a field of research that is currently gaining enormous attention. In this paper, we show some results on how to develop useful policies to execute maneuvers by a vehicle at high speeds with the mathematical optimization of some already established mobility conditions of the car. We also study how the presence of Gaussian noise on measurement sensors while maneuvering can disturb motion and affect the final trajectories. Different performance criteria for the optimization of such maneuvers are presented, and an analysis is shown on how path deviations can be minimized by using trajectory smoothing techniques like the Kalman Filter. We finalize the paper with a discussion on how communications can be used to implement these schemes.

  7. Measurement of photoemission and secondary emission from laboratory dust grains

    Science.gov (United States)

    Hazelton, Robert C.; Yadlowsky, Edward J.; Settersten, Thomas B.; Spanjers, Gregory G.; Moschella, John J.

    1995-01-01

    The overall goal of this project is experimentally determine the emission properties of dust grains in order to provide theorists and modelers with an accurate data base to use in codes that predict the charging of grains in various plasma environments encountered in the magnetospheres of the planets. In general these modelers use values which have been measured on planar, bulk samples of the materials in question. The large enhancements expected due to the small size of grains can have a dramatic impact upon the predictions and the ultimate utility of these predictions. The first experimental measurement of energy resolved profiles of the secondary electron emission coefficient, 6, of sub-micron diameter particles has been accomplished. Bismuth particles in the size range of .022 to .165 micrometers were generated in a moderate pressure vacuum oven (average size is a function of oven temperature and pressure) and introduced into a high vacuum chamber where they interacted with a high energy electron beam (0.4 to 20 keV). Large enhancements in emission were observed with a peak value, delta(sub max) = 4. 5 measured for the ensemble of particles with a mean size of .022 micrometers. This is in contrast to the published value, delta(sub max) = 1.2, for bulk bismuth. The observed profiles are in general agreement with recent theoretical predictions made by Chow et al. at UCSD.

  8. Acoustic emission measurement on large scale coils at JAERI

    International Nuclear Information System (INIS)

    Yoshida, K.; Hattori, Y.; Nishi, M.F.; Shimamoto, S.; Tsuji, H.

    1986-01-01

    The objective of acoustic emission measurement at Japan Atomic Energy Research Institute (JAERI) is an establishment of a general diagnostic method for superconducting magnet systems. Output of strain and displacement gages can not cover a whole system in monitoring premonitory phenomena of a magnet system s failure, because these sensors are mounted on points and therefore localized. Acoustic emissions can be transmitted to sensors through structural materials without electrical noise. Monitoring of acoustic emission will be one of the methods to predict a serious failure of magnet systems in a vacuum vessel. For this purpose, several sensors were installed on the Japanese LCT coil and the Test Module Coil (TMC). Some of acoustic activity was similar as seen in these coils. The correlation between voltage spikes and acoustic events is excellent during single coil charging mode, but poorer during out of plane force mode. There are no indicative acoustical phenomena before a magnet quench or during normal zone generation. The conditioning of acoustic events and voltage spikes can be seen after any cooling down. The localization of electrical insulation damage with the acoustic emission technique is one of its most useful applications

  9. Spectral emission measurements of lithium on the lithium tokamak experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gray, T. K.; Biewer, T. M.; Maingi, R. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Boyle, D. P.; Granstedt, E. M.; Kaita, R.; Majeski, R. P. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2012-10-15

    There has been a long-standing collaboration between ORNL and PPPL on edge and boundary layer physics. As part of this collaboration, ORNL has a large role in the instrumentation and interpretation of edge physics in the lithium tokamak experiment (LTX). In particular, a charge exchange recombination spectroscopy (CHERS) diagnostic is being designed and undergoing staged testing on LTX. Here we present results of passively measured lithium emission at 5166.89 A in LTX in anticipation of active spectroscopy measurements, which will be enabled by the installation of a neutral beam in 2013. Preliminary measurements are made in transient LTX plasmas with plasma current, I{sub p} < 70 kA, ohmic heating power, P{sub oh}{approx} 0.3 MW and discharge lifetimes of 10-15 ms. Measurements are made with a short focal length spectrometer and optics similar to the CHERS diagnostics on NSTX [R. E. Bell, Rev. Sci. Instrum. 68(2), 1273-1280 (1997)]. These preliminary measurements suggest that even without the neutral beam for active spectroscopy, there is sufficient passive lithium emission to allow for line-of-sight profile measurements of ion temperature, T{sub i}; toroidal velocity and v{sub t}. Results show peak T{sub i} = 70 eV and peak v{sub t} = 45 km/s were reached 10 ms into the discharge.

  10. Time interval measurement between to emission: a systematics

    International Nuclear Information System (INIS)

    Bizard, G.; Bougault, R.; Brou, R.; Colin, J.; Durand, D.; Genoux-Lubain, A.; Horn, D.; Kerambrun, A.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Lopez, O.; Louvel, M.; Mahi, M.; Meslin, C.; Steckmeyer, J.C.; Tamain, B.; Wieloch, A.

    1998-01-01

    A systematic study of the evolution of intervals of fragment emission times as a function of the energy deposited in the compound system was performed. Several measurements, Ne at 60 MeV/u, Ar at 30 and 60 MeV/u and two measurements for Kr at 60 MeV/u (central and semi-peripheral collisions) are presented. In all the experiments the target was Au and the mass of the compounds system was around A = 200. The excitation energies per nucleon reached in the case of these heavy systems cover the range of 3 to 5.5 MeV/u. The method used to determine the emission time intervals is based on the correlation functions associated to the relative angle distributions. The gaps between the data and simulations allow to evaluate the emission times. A rapid decrease of these time intervals was observed when the excitation energy increased. This variation starts at 500 fm/c which corresponds to a sequential emission. This relatively long time which indicates a weak interaction between fragments, corresponds practically to the measurement threshold. The shortest intervals (about 50 fm/c) are associated to a spontaneous multifragmentation and were observed in the case of central collisions at Ar+Au and Kr+Au at 60 MeV/u. Two interpretations are possible. The multifragmentation process might be viewed as a sequential process of very short time-separation or else, one can separate two zones heaving in mind that the multifragmentation is predominant from 4,5 MeV/u excitation energy upwards. This question is still open and its study is under way at LPC. An answer could come from the study of the rupture process of an excited nucleus, notably by the determination of its life-time

  11. Update on NOx measuring methods and emission levels

    International Nuclear Information System (INIS)

    Yamada, N.; Desprets, M.

    1997-01-01

    The survey was carried out in 1995 to update the NO x report prepared for presentation at the 19th World Gas Conference held in Milan in 1994 and drawn out on the basis of the information obtained through the survey carried out in 1992. Over the past three years the work on standard developments and/or improvements on NO x emissions has progressed in several IGU member countries. For example, in Europe a report on 'Determination of emissions from appliances burning gaseous fuels during type-testing' was drafted by European Committee for Standardization (CEN) in March 1994 as 'CR 1404 : 1994'. This report is based on the work so far carried out within MARCOGAZ, and it is expected that the NO x measuring methods specified in this report would be finally introduced into relevant gas appliance standards issued by CEN for type-testing of gas appliances covered by this report. (au)

  12. Instrument for benzene and toluene emission measurements of glycol regenerators

    International Nuclear Information System (INIS)

    Hanyecz, Veronika; Szabó, Gábor; Mohácsi, Árpád; Puskás, Sándor; Vágó, Árpád

    2013-01-01

    We introduce an in-field and in-explosive atmosphere useable instrument, which can measure the benzene and toluene concentration in two gas and two glycol samples produced by natural gas dehydration units. It is a two-phase, on-line gas chromatograph with a photoacoustic spectroscopy based detector. The time resolution is 10 min per cycle and the minimum detectable concentrations are 2 mg m −3 for benzene, 3 mg m −3 for toluene in natural gas, and 5 g m −3 for benzene and 6 g m −3 for toluene in glycol. Test measurements were carried out at a dehydration plant belonging to MOL Hungarian Oil and Gas Company. Benzene and toluene emissions of gas dehydration unit are calculated from the measured values based on mass balance of a glycol regenerator. The relationship between the outdoor temperature and the measured concentration was observed which is caused by temperature-dependent operation of the whole dehydration unit. Emission decreases with increase of outdoor temperature. (paper)

  13. Measurement of particle emission in automobil exhaust - application of continuous radiometric aerosol measurement to the emission of diesel engines

    International Nuclear Information System (INIS)

    Krasenbrink, A.; Georgi, B.

    1989-01-01

    The well-known method of measuring continuously dust by β-absorption is transferred to the problem of particle emission in automobile exhaust. With two similar dust-monitors FH62 having different sampling air flow rates and two low-pressure impactors the reliability of radiometric mass determination was verified. First static experiments with diesel soot showed the necessity of a dilution system, a new mass calibration with regard to the changed β-absorptivity and a quicker calculation of concentration for realtime measurements. (orig.) [de

  14. Implementation of Portable Emissions Measurement Systems (PEMS) for the Real-driving Emissions (RDE) Regulation in Europe.

    Science.gov (United States)

    Giechaskiel, Barouch; Vlachos, Theodoros; Riccobono, Francesco; Forni, Fausto; Colombo, Rinaldo; Montigny, Francois; Le-Lijour, Philippe; Carriero, Massimo; Bonnel, Pierre; Weiss, Martin

    2016-12-04

    Vehicles are tested in controlled and relatively narrow laboratory conditions to determine their official emission values and reference fuel consumption. However, on the road, ambient and driving conditions can vary over a wide range, sometimes causing emissions to be higher than those measured in the laboratory. For this reason, the European Commission has developed a complementary Real-Driving Emissions (RDE) test procedure using the Portable Emissions Measurement Systems (PEMS) to verify gaseous pollutant and particle number emissions during a wide range of normal operating conditions on the road. This paper presents the newly-adopted RDE test procedure, differentiating six steps: 1) vehicle selection, 2) vehicle preparation, 3) trip design, 4) trip execution, 5) trip verification, and 6) calculation of emissions. Of these steps, vehicle preparation and trip execution are described in greater detail. Examples of trip verification and the calculations of emissions are given.

  15. Virtual Induction Loops Based on Cooperative Vehicular Communications

    Directory of Open Access Journals (Sweden)

    Maria Calderon

    2013-01-01

    Full Text Available Induction loop detectors have become the most utilized sensors in traffic management systems. The gathered traffic data is used to improve traffic efficiency (i.e., warning users about congested areas or planning new infrastructures. Despite their usefulness, their deployment and maintenance costs are expensive. Vehicular networks are an emerging technology that can support novel strategies for ubiquitous and more cost-effective traffic data gathering. In this article, we propose and evaluate VIL (Virtual Induction Loop, a simple and lightweight traffic monitoring system based on cooperative vehicular communications. The proposed solution has been experimentally evaluated through simulation using real vehicular traces.

  16. An Efficient Computational Technique for Fractal Vehicular Traffic Flow

    Directory of Open Access Journals (Sweden)

    Devendra Kumar

    2018-04-01

    Full Text Available In this work, we examine a fractal vehicular traffic flow problem. The partial differential equations describing a fractal vehicular traffic flow are solved with the aid of the local fractional homotopy perturbation Sumudu transform scheme and the local fractional reduced differential transform method. Some illustrative examples are taken to describe the success of the suggested techniques. The results derived with the aid of the suggested schemes reveal that the present schemes are very efficient for obtaining the non-differentiable solution to fractal vehicular traffic flow problem.

  17. Virtual Induction Loops Based on Cooperative Vehicular Communications

    Science.gov (United States)

    Gramaglia, Marco; Bernardos, Carlos J.; Calderon, Maria

    2013-01-01

    Induction loop detectors have become the most utilized sensors in traffic management systems. The gathered traffic data is used to improve traffic efficiency (i.e., warning users about congested areas or planning new infrastructures). Despite their usefulness, their deployment and maintenance costs are expensive. Vehicular networks are an emerging technology that can support novel strategies for ubiquitous and more cost-effective traffic data gathering. In this article, we propose and evaluate VIL (Virtual Induction Loop), a simple and lightweight traffic monitoring system based on cooperative vehicular communications. The proposed solution has been experimentally evaluated through simulation using real vehicular traces. PMID:23348033

  18. The ARTEMIS European driving cycles for measuring car pollutant emissions.

    Science.gov (United States)

    André, Michel

    2004-12-01

    In the past 10 years, various work has been undertaken to collect data on the actual driving of European cars and to derive representative real-world driving cycles. A compilation and synthesis of this work is provided in this paper. In the frame of the European research project: ARTEMIS, this work has been considered to derive a set of reference driving cycles. The main objectives were as follows: to derive a common set of reference real-world driving cycles to be used in the frame of the ARTEMIS project but also in the frame of on-going national campaigns of pollutant emission measurements, to ensure the compatibility and integration of all the resulting emission data in the European systems of emission inventory; to ensure and validate the representativity of the database and driving cycles by comparing and taking into account all the available data regarding driving conditions; to include in three real-world driving cycles (urban, rural road and motorway) the diversity of the observed driving conditions, within sub-cycles allowing a disaggregation of the emissions according to more specific driving conditions (congested and free-flow urban). Such driving cycles present a real advantage as they are derived from a large database, using a methodology that was widely discussed and approved. In the main, these ARTEMIS driving cycles were designed using the available data, and the method of analysis was based to some extent on previous work. Specific steps were implemented. The study includes characterisation of driving conditions and vehicle uses. Starting conditions and gearbox use are also taken into account.

  19. Multi-source SO2 emission retrievals and consistency of satellite and surface measurements with reported emissions

    NARCIS (Netherlands)

    Fioletov, V.; McLinden, C.A.; Kharol, S.K.; Krotkov, N.A.; Li, C.; Joiner, J.; Moran, M.D.; Vet, R.; Visschedijk, A.J.H.; Denier Van Der Gon, H.A.C.

    2017-01-01

    Reported sulfur dioxide (SO2) emissions from US and Canadian sources have declined dramatically since the 1990s as a result of emission control measures. Observations from the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite and ground-based in situ measurements are examined to verify

  20. Measurement of amplified spontaneous emission at 200 A

    International Nuclear Information System (INIS)

    Ceglio, N.M.

    1985-01-01

    Recent interest in the production of laser radiation at soft x-ray wavelengths makes appropriate the discussion of diagnostic considerations and techniques for the measurement of same. A source of soft x-ray ASE has a number of characteristics which drive the design of diagnostic instruments: (1) the anisotropy of the ASE makes target alignment a critical part of the diagnosis, and couples collection solid angle to S/N considerations in the measurement; (2) the narrow linewidth of the amplified emission and its long wavelength put a high S/N premium on spectroscopic instrumentation of high spectral resolution and good higher-order discrimination; (3) the specialized plasma conditions required to produce gain are typically short lived, requiring time-resolved or at least time-discriminating spectroscopy; (4) the nonlinear nature of the threshold processes involved in ASE requires instrumentation of large dynamic range, broad angular acceptance, and large field of view and depth of focus. Of the many possible methods for gain verification of the x-ray source, five are discussed: (1) probe amplification; (2) spatial coherence measurement (as a function of gain length); (3) output intensity measurement (absolute measurement and nonlinear variation with gain length); (4) divergence measurement; and (5) cavity formation. In addition, recent soft x-ray laser experiments at LLNL are discussed along with descriptions of the instruments used to measure the ASE. Diagnostic design suggestions for future soft x-ray laser experiments are also presented

  1. Characteristics of On-road Diesel Vehicles: Black Carbon Emissions in Chinese Cities Based on Portable Emissions Measurement.

    Science.gov (United States)

    Zheng, Xuan; Wu, Ye; Jiang, Jingkun; Zhang, Shaojun; Liu, Huan; Song, Shaojie; Li, Zhenhua; Fan, Xiaoxiao; Fu, Lixin; Hao, Jiming

    2015-11-17

    Black carbon (BC) emissions from heavy-duty diesel vehicles (HDDVs) are rarely continuously measured using portable emission measurement systems (PEMSs). In this study, we utilize a PEMS to obtain real-world BC emission profiles for 25 HDDVs in China. The average fuel-based BC emissions of HDDVs certified according to Euro II, III, IV, and V standards are 2224 ± 251, 612 ± 740, 453 ± 584, and 152 ± 3 mg kg(-1), respectively. Notably, HDDVs adopting mechanical pump engines had significantly higher BC emissions than those equipped with electronic injection engines. Applying the useful features of PEMSs, we can relate instantaneous BC emissions to driving conditions using an operating mode binning methodology, and the average emission rates for Euro II to Euro IV diesel trucks can be constructed. From a macroscopic perspective, we observe that average speed is a significant factor affecting BC emissions and is well correlated with distance-based emissions (R(2) = 0.71). Therefore, the average fuel-based and distance-based BC emissions on congested roads are 40 and 125% higher than those on freeways. These results should be taken into consideration in future emission inventory studies.

  2. Methods of Temperature and Emission Measure Determination of Coronal Loops

    Science.gov (United States)

    Cirtain, J. W.; Schmelz, J. T.; Martens, P. C. H.

    2002-05-01

    Recent observational results from both SOHO-EIT and TRACE indicate that coronal loops are isothermal along their length (axially). These results are obtained from a narrowband filter ratio method that assumes that the plasma is isothermal along the line of sight (radially). However, these temperatures vary greatly from those derived from differential emission measure (DEM) curves produced from spectral lines recorded by SOHO-CDS. The DEM results indicate that the loops are neither axially nor radially isothermal. This discrepancy was investigated by Schmelz et al. (2001). They chose pairs of iron lines from the same CDS data set to mimic the EIT and TRACE loop results. Ratios of different lines gave different temperatures, indicating that the plasma was not radially isothermal. In addition the results indicated that the loop was axially isothermal, even though the DEM analysis of the same data showed this result to be false. Here we have analyzed the EIT data for the CDS loop published by Schmelz et al. (2001). We took the ratios of the 171-to-195 and 195-to-284 filter data, and made temperature maps of the loop. The results indicate that the loop is axially isothermal, but different temperatures were found for each pair of filters. Both ratio techniques force the resultant temperature to lie within the range where the response functions (for filters) or the emissivity functions (for lines) overlap; isothermal loops are therefore a byproduct of the analysis. This conclusion strengthens support for the idea that temperature and emission measure results from filter ratio methods may be misleading or even drastically wrong. This research was funded in part by the NASA/TRACE MODA grant for Montana State University. Solar physics research at the University of Memphis is supported by NASA grant NAG5-9783.

  3. Functional requirements document for measuring emissions of airborne radioactive materials

    International Nuclear Information System (INIS)

    Glissmeyer, J.A.; Alvarez, J.L.; Hoover, M.D.; Newton, G.C.; McFarland, A.R.; Rodgers, J.C.

    1994-11-01

    This document states the general functional requirements for systems and procedures for measuring emissions of airborne radioactive materials from facilities administered by the Westinghouse Hanford Company (WHC). The following issues are addressed in this document: lg-bullet definition of the program objectives lg-bullet selection of the overall approach to collecting the samples lg-bullet sampling equipment design lg-bullet sampling equipment maintenance and quality assurance issues. The following issues are not addressed in this document: lg-bullet air sampling in work areas or containments lg-bullet selection of specific on-line sample monitoring instrumentation lg-bullet analyzing collected samples lg-bullet reporting and interpreting results. The document provides equipment design guidance that is performance based rather than prescriptive. Locations from which samples are obtained should exhibit mixing of the contaminants with the airstream and acceptable air flow characteristics. Sample collection equipment and effluent and sample flow elements should meet defined performance standards. Quality control and assurance requirements specific to sample collection, equipment inspection, and calibration are presented. Key sample collection performance requirements are summarized in Section 5.4. The intent of this document is to assist WHC in demonstrating a high quality of air emission measurements with verified system performance based on documented system design, testing, inspection, and maintenance

  4. Road salt emissions: A comparison of measurements and modelling using the NORTRIP road dust emission model

    Science.gov (United States)

    Denby, B. R.; Ketzel, M.; Ellermann, T.; Stojiljkovic, A.; Kupiainen, K.; Niemi, J. V.; Norman, M.; Johansson, C.; Gustafsson, M.; Blomqvist, G.; Janhäll, S.; Sundvor, I.

    2016-09-01

    De-icing of road surfaces is necessary in many countries during winter to improve vehicle traction. Large amounts of salt, most often sodium chloride, are applied every year. Most of this salt is removed through drainage or traffic spray processes but a certain amount may be suspended, after drying of the road surface, into the air and will contribute to the concentration of particulate matter. Though some measurements of salt concentrations are available near roads, the link between road maintenance salting activities and observed concentrations of salt in ambient air is yet to be quantified. In this study the NORTRIP road dust emission model, which estimates the emissions of both dust and salt from the road surface, is applied at five sites in four Nordic countries for ten separate winter periods where daily mean ambient air measurements of salt concentrations are available. The model is capable of reproducing many of the salt emission episodes, both in time and intensity, but also fails on other occasions. The observed mean concentration of salt in PM10, over all ten datasets, is 4.2 μg/m3 and the modelled mean is 2.8 μg/m3, giving a fractional bias of -0.38. The RMSE of the mean concentrations, over all 10 datasets, is 2.9 μg/m3 with an average R2 of 0.28. The mean concentration of salt is similar to the mean exhaust contribution during the winter periods of 2.6 μg/m3. The contribution of salt to the kerbside winter mean PM10 concentration is estimated to increase by 4.1 ± 3.4 μg/m3 for every kg/m2 of salt applied on the road surface during the winter season. Additional sensitivity studies showed that the accurate logging of salt applications is a prerequisite for predicting salt emissions, as well as good quality data on precipitation. It also highlights the need for more simultaneous measurements of salt loading together with ambient air concentrations to help improve model parameterisations of salt and moisture removal processes.

  5. Pressurized transient otoacoustic emissions measured using click and chirp stimuli.

    Science.gov (United States)

    Keefe, Douglas H; Patrick Feeney, M; Hunter, Lisa L; Fitzpatrick, Denis F; Sanford, Chris A

    2018-01-01

    Transient-evoked otoacoustic emission (TEOAE) responses were measured in normal-hearing adult ears over frequencies from 0.7 to 8 kHz, and analyzed with reflectance/admittance data to measure absorbed sound power and the tympanometric peak pressure (TPP). The mean TPP was close to ambient. TEOAEs were measured in the ear canal at ambient pressure, TPP, and fixed air pressures from 150 to -200 daPa. Both click and chirp stimuli were used to elicit TEOAEs, in which the incident sound pressure level was constant across frequency. TEOAE levels were similar at ambient and TPP, and for frequencies from 0.7 to 2.8 kHz decreased with increasing positive and negative pressures. At 4-8 kHz, TEOAE levels were larger at positive pressures. This asymmetry is possibly related to changes in mechanical transmission through the ossicular chain. The mean TEOAE group delay did not change with pressure, although small changes were observed in the mean instantaneous frequency and group spread. Chirp TEOAEs measured in an adult ear with Eustachian tube dysfunction and TPP of -165 daPa were more robust at TPP than at ambient. Overall, results demonstrate the feasibility and clinical potential of measuring TEOAEs at fixed pressures in the ear canal, which provide additional information relative to TEOAEs measured at ambient pressure.

  6. Mechanical seal monitoring technique by acoustic emission measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kataoka, Tadashi; Fujita, Yoshihiro; Kawaguchi, Kazunori; Saito, Kazuhiro; Yokota, Setsuo; Hisada, Yasuhide; Masahiro, Komatsu

    1987-09-20

    This report describes a technique for mechanical seal monitoring through acoustic emission (AE) measurement. The equipment consists of an AE sensor, preamplifier, multiplexer, main amplifier, effective value transducer and computer system. When the sealed liquid pressure undergoes a large change, the seal surface configuration is monitored and evaluated accurately through AE measurement. If the mechanical seal surface id damaged or worn, the AE level is kept high or continues to fluctuate largely for a rather long period. When leak occurs, the AE value shows great fluctuations either at extremely low levels or at high levels. The former trend is considered to result from a decrease in solid contact due to an excessive amount of liquid film being formed at the seal surface during leak. In the latter case, the leak is attributed to severe damage to the seal surface. (18 figs, 1 tab, 5 photos, 3 refs)

  7. MIMO Techniques for Jamming Threat Suppression in Vehicular Networks

    Directory of Open Access Journals (Sweden)

    Dimitrios Kosmanos

    2016-01-01

    Full Text Available Vehicular ad hoc networks have emerged as a promising field of research and development, since they will be able to accommodate a variety of applications, ranging from infotainment to traffic management and road safety. A specific security-related concern that vehicular ad hoc networks face is how to keep communication alive in the presence of radio frequency jamming, especially during emergency situations. Multiple Input Multiple Output techniques are proven to be able to improve some crucial parameters of vehicular communications such as communication range and throughput. In this article, we investigate how Multiple Input Multiple Output techniques can be used in vehicular ad hoc networks as active defense mechanisms in order to avoid jamming threats. For this reason, a variation of spatial multiplexing is proposed, namely, vSP4, which achieves not only high throughput but also a stable diversity gain upon the interference of a malicious jammer.

  8. Mendenhall Glacier Visitor Center vehicular and pedestrian traffic congestion study

    Science.gov (United States)

    2007-05-01

    The Mendenhall Glacier Visitor Center of Tongass National Forest in Juneau, Alaska is experiencing vehicular and pedestrian congestion. This study was initiated by the United States Forest Service, Alaska Region, in cooperation with Western Federal L...

  9. Intelligent transportation systems 802 11-based vehicular communications

    CERN Document Server

    Hasan, Syed Faraz; Chakraborty, Shyam

    2017-01-01

    This book begins by describing a mathematical model that represents disruption in WLAN-based Vehicular Communications. Secondly, it sets out to reduce the handover latency for establishing quick connections between the mobile nodes and the roadside WLAN APs.

  10. Probability Based Evaluation of Vehicular Bridge Load using Weigh-in-Motion Data

    OpenAIRE

    Widi Nugraha; Indra Djati Sidi

    2016-01-01

    Load and Resistance Factored Design (LRFD) method for designing bridge in Indonesia have been implemented for more than 25 years. LRFD method treating loads and strengths variables as random variables with specific safety factors for different loads and strengths variables type. The nominal loads, load factors, reduction factors, and other criteria for bridge design code can be determined to meet the reliability criteria. Statistical data of weigh-in-motion (WIM) vehicular loads measurement i...

  11. Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City

    Directory of Open Access Journals (Sweden)

    D. A. Thornhill

    2010-04-01

    Full Text Available The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA using on-road measurements captured by a mobile laboratory combined with positive matrix factorization (PMF receptor modeling. During the MCMA-2006 ground-based component of the MILAGRO field campaign, the Aerodyne Mobile Laboratory (AML measured many gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO, nitrogen oxides (NOx, benzene, toluene, alkylated aromatics, formaldehyde, acetaldehyde, acetone, ammonia, particle number, fine particulate mass (PM2.5, and black carbon (BC. These serve as inputs to the receptor model, which is able to resolve three factors corresponding to gasoline engine exhaust, diesel engine exhaust, and the urban background. Using the source profiles, we calculate fuel-based emission factors for each type of exhaust. The MCMA's gasoline-powered vehicles are considerably dirtier, on average, than those in the US with respect to CO and aldehydes. Its diesel-powered vehicles have similar emission factors of NOx and higher emission factors of aldehydes, particle number, and BC. In the fleet sampled during AML driving, gasoline-powered vehicles are found to be responsible for 97% of total vehicular emissions of CO, 22% of NOx, 95–97% of each aromatic species, 72–85% of each carbonyl species, 74% of ammonia, negligible amounts of particle number, 26% of PM2.5, and 2% of BC; diesel-powered vehicles account for the balance. Because the mobile lab spent 17% of its time waiting at stoplights, the results may overemphasize idling conditions, possibly resulting in an underestimate of NOx and overestimate of CO emissions. On the other hand, estimates of the inventory that do not correctly account for emissions during idling are likely to produce bias in the opposite direction.The resulting fuel

  12. Measurement of undisturbed di-nitrogen emissions from aquatic ecosystems

    Science.gov (United States)

    Qin, Shuping, Clough, Timothy, Lou, Jiafa; Hu, Chunsheng; Oenema, Oene; Wrage-Mönnig, Nicole; Zhang, Yuming

    2016-04-01

    Increased production of reactive nitrogen (Nr) from atmospheric di-nitrogen (N2) during the last century has greatly contributed to increased food production1-4. However, enriching the biosphere with Nr through N fertilizer production, combustion, and biological N2 fixation has also caused a series of negative effects on global ecosystems 5,6, especially aquatic ecosystems7. The main pathway converting Nr back into the atmospheric N2 pool is the last step of the denitrification process, i.e., the reduction of nitrous oxide (N2O) into N2 by micro-organisms7,8. Despite several attempts9,10, there is not yet an accurate, fast and direct method for measuring undisturbed N2 fluxes from denitrification in aquatic sediments at the field scale11-14. Such a method is essential to study the feedback of aquatic ecosystems to Nr inputs1,2,7. Here we show that the measurement of both N2O emission and its isotope signature can be used to infer the undisturbed N2 fluxes from aquatic ecosystems. The microbial reduction of N2O increases the natural abundance of 15N-N2O relative to 14N-N2O (δ15N-N2O). We observed linear relationships between δ15N-N2O and the logarithmic transformed N2O/(N2+N2O) emission ratios. Through independent measurements, we verified that the undisturbed N2 flux from aquatic ecosystems can be inferred from measurements of N2O emissions and the δ15N-N2O signature. Our method allows the determination of field-scale N2 fluxes from undisturbed aquatic ecosystems, and thereby allows model predictions of denitrification rates to be tested. The undisturbed N2 fluxes observed are almost one order of magnitude higher than those estimated by the traditional method, where perturbation of the system occurs, indicating that the ability of aquatic ecosystems to remove Nr may have been severely underestimated.

  13. Atmospheric modeling to assess wind dependence in tracer dilution method measurements of landfill methane emissions.

    Science.gov (United States)

    Taylor, Diane M; Chow, Fotini K; Delkash, Madjid; Imhoff, Paul T

    2018-03-01

    The short-term temporal variability of landfill methane emissions is not well understood due to uncertainty in measurement methods. Significant variability is seen over short-term measurement campaigns with the tracer dilution method (TDM), but this variability may be due in part to measurement error rather than fluctuations in the actual landfill emissions. In this study, landfill methane emissions and TDM-measured emissions are simulated over a real landfill in Delaware, USA using the Weather Research and Forecasting model (WRF) for two emissions scenarios. In the steady emissions scenario, a constant landfill emissions rate is prescribed at each model grid point on the surface of the landfill. In the unsteady emissions scenario, emissions are calculated at each time step as a function of the local surface wind speed, resulting in variable emissions over each 1.5-h measurement period. The simulation output is used to assess the standard deviation and percent error of the TDM-measured emissions. Eight measurement periods are simulated over two different days to look at different conditions. Results show that standard deviation of the TDM- measured emissions does not increase significantly from the steady emissions simulations to the unsteady emissions scenarios, indicating that the TDM may have inherent errors in its prediction of emissions fluctuations. Results also show that TDM error does not increase significantly from the steady to the unsteady emissions simulations. This indicates that introducing variability to the landfill emissions does not increase errors in the TDM at this site. Across all simulations, TDM errors range from -15% to 43%, consistent with the range of errors seen in previous TDM studies. Simulations indicate diurnal variations of methane emissions when wind effects are significant, which may be important when developing daily and annual emissions estimates from limited field data. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Plasma promoted manufacturing of hydrogen and vehicular applications

    Science.gov (United States)

    Bromberg, Leslie

    2003-10-01

    Plasmas can be used for promoting reformation of fuels. Plasma-based reformers developed at MIT use a low temperature, low power, low current electrical discharge to promote partial oxidation conversion of hydrocarbon fuels into hydrogen and CO. The very fuel rich mixture is hard to ignite, and the plasmatron provides a volume-ignition. To minimize erosion and to simplify the power supply, a low current high voltage discharge is used, with wide area electrodes. The plasmatron fuel reformer operates at or slightly above atmospheric pressure. The plasma-based reformer technology provides the advantages of rapid startup and transient response; efficient conversion of the fuel to hydrogen rich gas; compact size; relaxation or elimination of reformer catalyst requirements; and capability to process difficult to reform fuels. These advantages enable use of hydrogen-manufacturing reformation technology in cars using available fuels, such as gasoline and diesel. This plasma-based reformer technology can provide substantial throughputs even without the use of a catalyst. The electrical power consumption of the device is minimized by design and operational characteristics (less than 500 W peak and 200 W average). The product from these plasma reactors is a hydrogen rich mixture that can be used for combustion enhancement and emissions aftertreatment in vehicular applications. By converting a small fraction of the fuel to hydrogen rich gas, in-cylinder combustion can be improved. With minor modification of the engine, use of hydrogen rich gas results in increased fuel efficiency and decreased emissions of smog producing gases. The status of plasma based reformer technology and its application to vehicles will be described.

  15. Measurement of regional cerebral blood flow by positron emission tomography

    International Nuclear Information System (INIS)

    Herscovitch, P.; Powers, W.J.

    1987-01-01

    The principal advantage of positron emission tomography over other methods for measuring cerebral blood flow stems from the accurate, quantitative three-dimensional measurements of regional brain radioactivity that are possible with this technique. As a result, accurate quantitative measurements of regional cerebral blood flow can be obtained for both superficial and deep cerebral structures. The value of PET for investigating central nervous system physiology and pathology extends far beyond this, however. Through the use of different radiotracers and appropriate mathematical models, PET can be applied to the measurement of a wide variety of physiologic variables. Measurements of rCBF tell only part of the story. Experience with PET and with a variety of other techniques has taught us that rCBF is at times a poor indicator of the metabolic, functional, and biochemical status of cerebral tissue. It is only by understanding the interaction of all of these factors that our understanding of neurologic disease can advance. It is in the investigation of these complex relationships that the real value of PET resides

  16. Vehicle emission factors of solid nanoparticles in the laboratory and on the road using Portable Emission Measurement Systems (PEMS

    Directory of Open Access Journals (Sweden)

    Barouch eGiechaskiel

    2015-12-01

    Full Text Available Emission inventories are used to quantify sources and identify trends in the emissions of air pollutants. They use vehicle-specific emission factors that are typically determined in the laboratory, through remote-sensing, vehicle chasing experiments and, more recently, on-board Portable Emission Measurement Systems (PEMS. Although PEMS is widely applied to measure gaseous pollutants, their application to Solid Particle Number (SPN emissions is new. In this paper, we discuss the current status of determining SPN emission factors both on the chassis dynamometer and on-road using PEMS-SPN. First, we determine the influence of the measurement equipment, ambient temperature, driving style and cycle characteristics, and the extra mass of the PEMS equipment on the SPN emissions. Afterward, we present the SPN emissions under type-approval conditions as well as on the road of two heavy-duty diesel vehicles equipped with Diesel Particulate Filter (DPF (one Euro VI, two light-duty diesel vehicles equipped with DPF, one light-duty vehicle equipped with a Port Fuel Injection engine (PFI, and seven Gasoline Direct Injection (GDI passenger cars (two Euro 6. We find that cold-start and strong accelerations tend to substantially increase SPN emissions. The two heavy-duty vehicles showed emissions around 2×10^13 p/km (Euro V truck and 6×10^10 p/km (Euro VI truck, respectively. One of the DPF-equipped light-duty vehicles showed emissions of 8×10^11 p/km, while the other one had one order of magnitude lower emissions. The PFI car had SPN emissions slightly higher than 1×10^12 p/km. The emissions of GDI cars spanned approximately from 8×10^11 p/km to 8×10^12 p/km. For the cars without DPF, the SPN emissions remained within a factor of two of the laboratory results. This factor was on average around 0.8 for the Euro 6 and 1.6 for the Euro 5 GDIs. The DPF equipped vehicles showed a difference of almost one order of magnitude between laboratory and on-road tests

  17. Linearized spectrum correlation analysis for line emission measurements.

    Science.gov (United States)

    Nishizawa, T; Nornberg, M D; Den Hartog, D J; Sarff, J S

    2017-08-01

    A new spectral analysis method, Linearized Spectrum Correlation Analysis (LSCA), for charge exchange and passive ion Doppler spectroscopy is introduced to provide a means of measuring fast spectral line shape changes associated with ion-scale micro-instabilities. This analysis method is designed to resolve the fluctuations in the emission line shape from a stationary ion-scale wave. The method linearizes the fluctuations around a time-averaged line shape (e.g., Gaussian) and subdivides the spectral output channels into two sets to reduce contributions from uncorrelated fluctuations without averaging over the fast time dynamics. In principle, small fluctuations in the parameters used for a line shape model can be measured by evaluating the cross spectrum between different channel groupings to isolate a particular fluctuating quantity. High-frequency ion velocity measurements (100-200 kHz) were made by using this method. We also conducted simulations to compare LSCA with a moment analysis technique under a low photon count condition. Both experimental and synthetic measurements demonstrate the effectiveness of LSCA.

  18. Wide angle Michelson Doppler imaging interferometer. [measuring atmospheric emissions

    Science.gov (United States)

    Shepherd, G. G.

    1980-01-01

    The optical system, stepping control, phase and modulation depth, array detector, and directions sensor are described for a specialized type of Michelson interferometer which works at sufficiently high resolution to measure the line widths and Doppler shifts of naturally occurring atmospheric emissions. With its imaging capability, the instrument can potentially supply this data independently for each element of the 100 x 100 detector array. The experiment seeks: (1) to obtain vertical profiles of atmospheric winds and temperatures as functions of latitude by observing near the limb; (2) to acquire exploratory wind and temperature data on smaller scale structures in airglow irregularities and in auroral forms; and (3) to collaborate with other Spacelab experiments, such as barium cloud releases, in providing wind and temperature data.

  19. Development and application of a mobile laboratory for measuring emissions from diesel engines. 1. Regulated gaseous emissions.

    Science.gov (United States)

    Cocker, David R; Shah, Sandip D; Johnson, Kent; Miller, J Wayne; Norbeck, Joseph M

    2004-04-01

    Information about in-use emissions from diesel engines remains a critical issue for inventory development and policy design. Toward that end, we have developed and verified the first mobile laboratory that measures on-road or real-world emissions from engines at the quality level specified in the U.S. Congress Code of Federal Regulations. This unique mobile laboratory provides information on integrated and modal regulated gaseous emission rates and integrated emission rates for speciated volatile and semivolatile organic compounds and particulate matter during real-world operation. Total emissions are captured and collected from the HDD vehicle that is pulling the mobile laboratory. While primarily intended to accumulate data from HDD vehicles, it may also be used to measure emission rates from stationary diesel sources such as back-up generators. This paper describes the development of the mobile laboratory, its measurement capabilities, and the verification process and provides the first data on total capture gaseous on-road emission measurements following the California Air Resources Board (ARB) 4-mode driving cycle, the hot urban dynamometer driving schedule (UDDS), the modified 5-mode cycle, and a 53.2-mi highway chase experiment. NOx mass emission rates (g mi(-1)) for the ARB 4-mode driving cycle, the hot UDDS driving cycle, and the chase experimentwerefoundto exceed current emission factor estimates for the engine type tested by approximately 50%. It was determined that congested traffic flow as well as "off-Federal Test Procedure cycle" emissions can lead to significant increases in per mile NOx emission rates for HDD vehicles.

  20. NOAA Mobile Laboratory Measures Oil and Gas Emissions

    Science.gov (United States)

    Kofler, J. D.; Petron, G.; Dube, W. P.; Edwards, P. M.; Brown, S. S.; Geiger, F.; Patrick, L.; Crepinsek, S.; Chen, H.; Miller, B. R.; Montzka, S. A.; Lang, P. M.; Newberger, T.; Higgs, J. A.; Sweeney, C.; Guenther, D.; Karion, A.; Wolter, S.; Williams, J.; Jordan, A.; Tans, P. P.; Schnell, R. C.

    2012-12-01

    A van capable of continuous real time measurements of CH4 , CO2, CO, Water Vapor, Ozone, NO, NO2, Volatile Organic Compounds VOCs including aromatics and other traces gases was driven in the oil and gas fields of the Uintah Basin in northeastern Utah. Compressor Stations, processing plants, oil and gas well heads. Separators, condensate tanks, evaporation pond disposal facilities, holding tanks, hydraulic fracturing sites, gas pipelines and more were studied using the van. The mobile measurements provide a powerful tool to get to the source of the emissions and reveal the unique chemical signature of each of the stages and components of oil and gas production as well as the overall basin and background gas concentrations. In addition to a suite of gas analyzers, the van includes a meteorological system (temperature, humidity, and wind speed and direction), GPS tracking, flask sampling system and a batter power system. Aspects of the vans hardware, sampling methods and operations are discussed along with a few highlights of the measurements.

  1. Driving cycles for measuring passenger car emissions on roads with traffic calming measures

    International Nuclear Information System (INIS)

    Boulter, P.G.; Latham, S.; Ainge, M.

    1999-01-01

    Although local authorities in the UK need to be aware of any air quality impacts resulting from their traffic calming operations, there is little information relating to the effects of different traffic calming measures. The effects on air quality on this scale are complex, and so TRL is providing guidance by developing performance indices for different measures based on their effects on vehicle emissions. The emissions indices for passenger cars are based on tests conducted on a chassis dynamometer, and this paper describes the development of the methodology for constructing the driving cycles to be used. The technique involves the measurement of the speed profiles of a large number of vehicles using a roadside LIDAR system, and the determination of typical gear selections using three-instrumented cars

  2. Control de tráfico vehicular usando ANFIS Vehicular traffic control using ANFIS

    Directory of Open Access Journals (Sweden)

    Luis Fernando Pedraza

    2012-04-01

    Full Text Available Diferentes estrategias para el control del tráfico urbano se han presentado a lo largo del tiempo. Este artículo presenta el diseño de un modelo de tráfico vehicular, el cual examina el tráfico existente en una vía a través de una serie de semáforos. A partir de este modelo se sincronizan los tiempos de duración y de desfase de los semáforos, utilizando para ello el Sistema de Inferencia Difusa Basado en Redes Adaptativas (ANFIS. El modelo es simulado y los resultados se evalúan a nivel macroscópico con el modelo de tiempos fijos, que funciona actualmente en Bogotá-Colombia.Different strategies for urban traffic control have been presented over time. This paper presents the design of a vehicular traffic model, examining the existing traffic through a serie of traffic lights on a road. From this model the times of duration and phase of the traffic lights are synchronized, using the Adaptive Network Based Fuzzy Inference Systems (ANFIS. The model is simulated and the results are evaluated at macroscopic level with the fixed time model, currently operating in Bogota-Colombia.

  3. Acoustic emission measurements in petroleum-related rock mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Unander, Tor Erling

    2002-07-01

    Acoustic emission activity in rock has usually been studied in crystalline rock, which reflects that rock mechanics has also mostly been occupied with such rocks in relations to seismology, mining and tunneling. On the other hand, petroleum-related rock mechanics focuses on the behaviour of sedimentary rock. Thus, this thesis presents a general study of acoustic emission activity in sedimentary rock, primarily in sandstone. Chalk, limestone and shale have also been tested, but to much less degree because the AE activity in these materials is low. To simplify the study, pore fluids have not been used. The advent of the personal computer and computerized measuring equipment have made possible new methods both for measuring and analysing acoustic emissions. Consequently, a majority of this work is devoted to the development and implementation of new analysis techniques. A broad range of topics are treated: (1) Quantification of the AE activity level, assuming that the event rate best represents the activity. An algorithm for estimating the event rate and a methodology for objectively describing special changes in the activity e.g., onset determination, are presented. (2) Analysis of AE waveform data. A new method for determining the source energy of an AE event is presented, and it is shown how seismic source theory can be used to analyze even intermediate quality data. Based on these techniques, it is shown that a major part of the measured AE activity originates from a region close to the sensor, not necessarily representing the entire sample. (3) An improved procedure for estimating source locations is presented. The main benefit is a procedure that better handles arrival time data with large errors. Statistical simulations are used to quantify the uncertainties in the locations. The analysis techniques are developed with the application to sedimentary rock in mind, and in two articles, the techniques are used in the study of such materials. The work in the first

  4. Evaluation of H.264/AVC over IEEE 802.11p vehicular networks

    Science.gov (United States)

    Rozas-Ramallal, Ismael; Fernández-Caramés, Tiago M.; Dapena, Adriana; García-Naya, José Antonio

    2013-12-01

    The capacity of vehicular networks to offer non-safety services, like infotainment applications or the exchange of multimedia information between vehicles, have attracted a great deal of attention to the field of Intelligent Transport Systems (ITS). In particular, in this article we focus our attention on IEEE 802.11p which defines enhancements to IEEE 802.11 required to support ITS applications. We present an FPGA-based testbed developed to evaluate H.264/AVC (Advanced Video Coding) video transmission over vehicular networks. The testbed covers some of the most common situations in vehicle-to-vehicle and roadside-to-vehicle communications and it is highly flexible, allowing the performance evaluation of different vehicular standard configurations. We also show several experimental results to illustrate the quality obtained when H.264/AVC encoded video is transmitted over IEEE 802.11p networks. The quality is measured considering two important parameters: the percentage of recovered group of pictures and the frame quality. In order to improve performance, we propose to substitute the convolutional channel encoder used in IEEE 802.11p for a low-density parity-check code encoder. In addition, we suggest a simple strategy to decide the optimum number of iterations needed to decode each packet received.

  5. Measurement of the attosecond emission from aligned molecules

    International Nuclear Information System (INIS)

    Boutu, W.; Merdji, H.; Fitour, R.; Monchicourt, P.; Breger, P.; Carre, B.; Salieres, P.

    2006-01-01

    Complete test of publication follows. Recently, a number of papers have demonstrated the interest of high-order harmonic generation (HHG) from molecules aligned with respect to the laser polarization. Itatani et al. (Nature 432, 867 (2004)) have shown that a precise characterization of the harmonic emission allows performing a tomographic reconstruction of the molecular orbitals that radiate. Kanai et al. (Nature 435, 470 (2005)) have evidenced quantum interferences in the recombination process of HHG that are directly related to the molecular structure. In all of these papers, only the HHG intensity was measured. The relative harmonic phase, though more difficult to measure, contains important information on the interference process, and is needed for an ab initio tomographic reconstruction. Finally, while the attosecond emission from atoms has been thoroughly studied, in particular by our group (Mairesse et al., Science (302, 1540 (2003)), it has not been investigated in molecules. In a first experiment (Wabnitz et al., EPJD (2006)), we measured the amplitude and relative phase of harmonics radiated by un-aligned nitrogen molecules. Small but reproducible deviations from the phase of harmonics generated in argon (same ionization potential as nitrogen) were measured for low orders. In a recent experiment, we have measured, up to high order, the harmonic amplitude and relative phase for aligned molecules (N 2 and CO 2 ). In order to align the molecules, we used the so-called nonadiabatic technique: a rotational wavepacket is created by a strong enough and short aligning pulse, so that a field-free alignment is obtained at the revival (a few ps after the aligning pulse). The measurement of phase locking between neighboring harmonics was performed through the photoionization of a target gas by the harmonic beam in presence of a sufficiently intense 'dressing' laser beam (RABITT technique). The harmonic phase measured when the CO 2 molecules are aligned parallel to

  6. Comparative study of radiometric and calorimetric methods for total hemispherical emissivity measurements

    Science.gov (United States)

    Monchau, Jean-Pierre; Hameury, Jacques; Ausset, Patrick; Hay, Bruno; Ibos, Laurent; Candau, Yves

    2018-05-01

    Accurate knowledge of infrared emissivity is important in applications such as surface temperature measurements by infrared thermography or thermal balance for building walls. A comparison of total hemispherical emissivity measurement was performed by two laboratories: the Laboratoire National de Métrologie et d'Essais (LNE) and the Centre d'Études et de Recherche en Thermique, Environnement et Systèmes (CERTES). Both laboratories performed emissivity measurements on four samples, chosen to cover a large range of emissivity values and angular reflectance behaviors. The samples were polished aluminum (highly specular, low emissivity), bulk PVC (slightly specular, high emissivity), sandblasted aluminum (diffuse surface, medium emissivity), and aluminum paint (slightly specular surface, medium emissivity). Results obtained using five measurement techniques were compared. LNE used a calorimetric method for direct total hemispherical emissivity measurement [1], an absolute reflectometric measurement method [2], and a relative reflectometric measurement method. CERTES used two total hemispherical directional reflectometric measurement methods [3, 4]. For indirect techniques by reflectance measurements, the total hemispherical emissivity values were calculated from directional hemispherical reflectance measurement results using spectral integration when required and directional to hemispherical extrapolation. Results were compared, taking into account measurement uncertainties; an added uncertainty was introduced to account for heterogeneity over the surfaces of the samples and between samples. All techniques gave large relative uncertainties for a low emissive and very specular material (polished aluminum), and results were quite scattered. All the indirect techniques by reflectance measurement gave results within ±0.01 for a high emissivity material. A commercial aluminum paint appears to be a good candidate for producing samples with medium level of emissivity

  7. Amplified spontaneous emission measurements on the Aurora large aperture module

    International Nuclear Information System (INIS)

    Oertel, J.A.; Czuchlewski, S.J.; Leland, W.T.; Turner, T.P.

    1990-01-01

    The large aperture module (LAM) of the Aurora KrF laser can be used to address a number of issues that relate to the scaling of KrF amplifiers to larger ICF systems. Perhaps foremost among these are the possible effects of amplified spontaneous emission (ASE) on laser performance. To assess this problem a 3-D computer code has been developed to model these ASE effects. The code uses an iterative procedure to arrive at a self-consistent steady state solution to the 3-D distribution of coherent and incoherent fluxes within the amplifier. Two-pass energy extraction, wall reflectivity, and nonuniform excitation are included in the model. The authors previously reported the effects of ASE on the small signal gains measured in the 1- x 1- x 2-m 3 LAM. The code also makes quantitative predictions of the ASE that should be generated in the amplifier. This paper indicates the radiance expected for a medium of uniform gain in terms of the (g - ν)L product and the parameter g/a. The quantity (g - ν)L is the product of the net gain and the path length along the direction of observation. The present experiments compare values of ASE measured at various locations around the LAM with the code predictions. The impact of ASE on amplifier output, is also discussed

  8. Measurements of the Secondary Electron Emission of Some Insulators

    CERN Document Server

    Bozhko, Y.; Hilleret, N.

    2013-01-01

    Charging up the surface of an insulator after beam impact can lead either to reverse sign of field between the surface and collector of electrons for case of thick sample or appearance of very high internal field for thin films. Both situations discard correct measurements of secondary electron emission (SEE) and can be avoided via reducing the beam dose. The single pulse method with pulse duration of order of tens microseconds has been used. The beam pulsing was carried out by means of an analog switch introduced in deflection plate circuit which toggles its output between "beam on" and "beam off" voltages depending on level of a digital pulse. The error in measuring the beam current for insulators with high value of SEE was significantly reduced due to the use for this purpose a titanium sample having low value of the SEE with DC method applied. Results obtained for some not coated insulators show considerable increase of the SEE after baking out at 3500C what could be explained by the change of work functi...

  9. Velocity field measurement in micro-bubble emission boiling

    International Nuclear Information System (INIS)

    Ito, Daisuke; Saito, Yasushi; Natazuka, Jun

    2017-01-01

    Liquid inlet behavior to a heat surface in micro-bubble emission boiling (MEB) was investigated by flow measurement using particle image velocimetry (PIV). Subcooled pool boiling experiments under atmospheric pressure were carried out using a heat surface with a diameter of 10 mm. An upper end of a heater block made of copper was used as the heat surface. Working fluid was the deionized water and the subcooling was varied from 40 K to 70 K. Three K-type thermocouples were installed in the copper block to measure the temperature gradient, and the heat flux and wall superheat were estimated from these temperature data to make a boiling curve. The flow visualization around the heat surface was carried out using a high-speed video camera and a light sheet. The microbubbles generated in the MEB were used as tracer particles and the velocity field was obtained by PIV analysis of the acquired image sequence. As a result, the higher heat fluxes than the critical heat flux could be obtained in the MEB region. In addition, the distribution characteristics of the velocity in MEB region were studied using the PIV results and the location of the stagnation point in the velocity fields was discussed. (author)

  10. Metabolic assessments during extra-vehicular activity

    Science.gov (United States)

    Osipov, Yu. Yu.; Spichkov, A. N.; Filipenkov, S. N.

    Extra-vehicular activity (EVA) has a significant role during extended space flights. It demonstrates that humans can survive and perform useful work outside the Orbital Space Stations (OSS) while wearing protective space suits (SS). When the International Space Station 'Alpha'(ISSA) is fully operational, EVA assembly, installation, maintenance and repair operations will become an everyday repetitive work activity in space. It needs new ergonomic evaluation of the work/rest schedule for an increasing of the labor amount per EVA hour. The metabolism assessment is a helpful method to control the productivity of the EVA astronaut and to optimize the work/rest regime. Three following methods were used in Russia to estimate real-time metabolic rates during EVA: 1. Oxygen consumption, computed from the pressure drop in a high pressure bottle per unit time (with actual thermodynamic oxygen properties under high pressure and oxygen leakage taken into account). 2. Carbon dioxide production, computed from CO 2 concentration at the contaminant control cartridge and gas flow rate in the life support subsystem closed loop (nominal mode) or gas leakage in the SS open loop (emergency mode). 3. Heat removal, computed from the difference between the temperatures of coolant water or gas and its flow rate in a unit of time (with assumed humidity and wet oxygen state taken into account). Comparison of heat removal values with metabolic rates enables us to determine the thermal balance during an operative medical control of EVA at "Salyut-6", "Salyut-7" and "Mir" OSS. Complex analysis of metabolism, body temperature and heat rate supports a differential diagnosis between emotional and thermal components of stress during EVA. It gives a prognosis of human homeostasis during EVA. Available information has been acquired into an EVA data base which is an effective tool for ergonomical optimization.

  11. Control of combustion generated emissions from spark ignition engines: a review

    International Nuclear Information System (INIS)

    Mansha, M.; Shahid, E.M.; Qureshi, A.H.

    2012-01-01

    For the past several decades automobiles have been a major source of ground level emissions of various pollutants like CO, HC, NO/sub x/, SO/sub x/ CO/sub 2/, etc. Due to their dangerous effects on human health, vegetation and on climate, various pre combustion, in-cylinder and post. combustion techniques have been tried for their abatement. This paper reviews all of the workable measures taken so far to controlling the combustion generated emissions from 4-stroke Spark Ignition Vehicular Engines ever since the promulgation of emission control legislation/standards and their subsequent enforcement in the late 1960s. (author)

  12. Real-world operation conditions and on-road emissions of Beijing diesel buses measured by using portable emission measurement system and electric low-pressure impactor.

    Science.gov (United States)

    Liu, Zhihua; Ge, Yunshan; Johnson, Kent C; Shah, Asad Naeem; Tan, Jianwei; Wang, Chu; Yu, Linxiao

    2011-03-15

    On-road measurement is an effective method to investigate real-world emissions generated from vehicles and estimate the difference between engine certification cycles and real-world operating conditions. This study presents the results of on-road measurements collected from urban buses which propelled by diesel engine in Beijing city. Two widely used Euro III emission level buses and two Euro IV emission level buses were chosen to perform on-road emission measurements using portable emission measurement system (PEMS) for gaseous pollutant and Electric Low Pressure Impactor (ELPI) for particulate matter (PM) number emissions. The results indicate that considerable discrepancies of engine operating conditions between real-world driving cycles and engine certification cycles have been observed. Under real-world operating conditions, carbon monoxide (CO) and hydrocarbon (HC) emissions can easily meet their respective regulations limits, while brake specification nitrogen oxide (bsNO(x)) emissions present a significant deviation from its corresponding limit. Compared with standard limits, the real-world bsNO(x) emission of the two Euro III emission level buses approximately increased by 60% and 120% respectively, and bsNO(x) of two Euro IV buses nearly twice standard limits because Selective Catalytic Reduction (SCR) system not active under low exhaust temperature. Particle mass were estimated via particle size distribution with the assumption that particle density and diameter is liner. The results demonstrate that nanometer size particulate matter make significant contribution to total particle number but play a minor role to total particle mass. It is suggested that specific certified cycle should be developed to regulate bus engines emissions on the test bench or use PEMS to control the bus emissions under real-world operating conditions. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Acoustic emission measurements at the pressure vessel ZB2

    International Nuclear Information System (INIS)

    Tirbonod, B.; Hanacek, L.

    1990-01-01

    The work presented here is the Swiss contribution to the project 'Zwischenbehaelter 2 (ZB2)' hosted by the 'Bundesministerium fuer Forschung und Technologie' of the Federal Republic of Germany. One of the crack-like defects introduced at the inside surface of the thick-walled pressure vessel ZB2 was locally monitored by acoustic emission. The measurement system was broadband (0.5 - 5 MHz) and allowed a threedimensional location of the source. The vessel was subjected to different tests. Signals were recorded during the second series of hydrotests, fast pressure cycles and fatigue test at 50 C. About 1 signal per hydrotest or cycle was recorded. For the hydrotests the signals were recorded generally at loading in the intermediate range of pressure; the sources were located in the artificial defect. Recurrent and non recurrent signals were recorded during the fatigue test. At loading, signals were captured up to the maximum pressure and for the recurrent signals at well defined pressure ranges. All the sources (except one, located in the base material ahead of the artificial defect) were situated in the artificial defect. The pressure and location depended on the loading phase and on the cycle range. The measurements were discussed by describing the signals by measurement, signal and source parameters. The goal was to identify the source mechanism and to assess the growth of the defect. For the hydrotests the identification of the mechanism at loading remains open. For the fatigue test the source situated in the base material was attributed to a primary mechanism; this source could assess the growth of the defect on the basis of linear elastic fracture mechanics. A secondary mechanism was suggested for recurrent sources active at loading. For all the tests, the sources active at unloading were attributed to a secondary mechanism. (author)

  14. A Vehicular Guidance Wireless Sensor/Actuator Network

    KAUST Repository

    Boudellioua, Imene

    2012-07-01

    Sensor networks have been heralded as one of 21 most important technologies for the 21st century by Business Week [1]. Wireless sensor/actuator networks (WSANs)are emerging as a new generation of sensor networks with the potential for enhancing the versatility and effectiveness of sensor networks. However, the unreliability of wireless communications and the real-time requirements of control applications raise great challenges for WSAN design. In this thesis, we design a WSAN for a vehicular guidance system targeting environmental disaster management applications. In this system, actuators provide mobility to all sensor nodes in the observed area whenever needed. Moreover, nodes form clusters and their movement is controlled by a master node that is selected dynamically. We also discuss the factors affecting our network performance in real-life and propose a framework which accounts for real-time requirement and reliable actuation. We finally perform some experimental studies on our system to measure its performance in an indoor environment.

  15. Autonomous Car Parking System through a Cooperative Vehicular Positioning Network.

    Science.gov (United States)

    Correa, Alejandro; Boquet, Guillem; Morell, Antoni; Lopez Vicario, Jose

    2017-04-13

    The increasing development of the automotive industry towards a fully autonomous car has motivated the design of new value-added services in Vehicular Sensor Networks (VSNs). Within the context of VSNs, the autonomous car, with an increasing number of on-board sensors, is a mobile node that exchanges sensed and state information within the VSN. Among all the value added services for VSNs, the design of new intelligent parking management architectures where the autonomous car will coexist with traditional cars is mandatory in order to profit from all the opportunities associated with the increasing intelligence of the new generation of cars. In this work, we design a new smart parking system on top of a VSN that takes into account the heterogeneity of cars and provides guidance to the best parking place for the autonomous car based on a collaborative approach that searches for the common good of all of them measured by the accessibility rate, which is the ratio of the free parking places accessible for an autonomous car. Then, we simulate a real parking lot and the results show that the performance of our system is close to the optimum considering different communication ranges and penetration rates for the autonomous car.

  16. Autonomous Car Parking System through a Cooperative Vehicular Positioning Network

    Science.gov (United States)

    Correa, Alejandro; Boquet, Guillem; Morell, Antoni; Lopez Vicario, Jose

    2017-01-01

    The increasing development of the automotive industry towards a fully autonomous car has motivated the design of new value-added services in Vehicular Sensor Networks (VSNs). Within the context of VSNs, the autonomous car, with an increasing number of on-board sensors, is a mobile node that exchanges sensed and state information within the VSN. Among all the value added services for VSNs, the design of new intelligent parking management architectures where the autonomous car will coexist with traditional cars is mandatory in order to profit from all the opportunities associated with the increasing intelligence of the new generation of cars. In this work, we design a new smart parking system on top of a VSN that takes into account the heterogeneity of cars and provides guidance to the best parking place for the autonomous car based on a collaborative approach that searches for the common good of all of them measured by the accessibility rate, which is the ratio of the free parking places accessible for an autonomous car. Then, we simulate a real parking lot and the results show that the performance of our system is close to the optimum considering different communication ranges and penetration rates for the autonomous car. PMID:28406426

  17. Analysis and Visualization of Urban Emission Measurements in Smart Cities

    DEFF Research Database (Denmark)

    Ahlers, Dirk; Kraemer, Frank Alexander; Braten, Anders Eivind

    2018-01-01

    Cities worldwide aim to reduce their greenhouse gas emissions and improve air quality for their citizens. Therefore, there is a need to implement smart city approaches to monitor, model, and understand local emissions to better guide these actions. We present our approach that deploys a number of...

  18. Locomotive emissions measurements for various blends of biodiesel fuel.

    Science.gov (United States)

    2014-12-01

    The objective of this project was to assess the effects of various blends of biodiesel on locomotive engine exhaust emissions. The : emission tests were conducted on two locomotive models, a Tier 2 EMD SD70ACe and a Tier 1 Plus GE Dash9-44CW, using t...

  19. Acoustic emission signal measurements in pressure vessel testing

    International Nuclear Information System (INIS)

    Peter, A.

    1984-01-01

    The number of acoustic emission events per plastically deformed unit of volume caused by artificial notches in real pressure vessels has been calculated taking into account reference voltage, distance between acoustic emission source and sensor as well as the effect of noise background. A test performed at a 100 m 3 gasholder verifies the theoretical considerations. (author)

  20. Gathering pipeline methane emissions in Fayetteville shale pipelines and scoping guidelines for future pipeline measurement campaigns

    Directory of Open Access Journals (Sweden)

    Daniel J. Zimmerle

    2017-11-01

    Full Text Available Gathering pipelines, which transport gas from well pads to downstream processing, are a sector of the natural gas supply chain for which little measured methane emissions data are available. This study performed leak detection and measurement on 96 km of gathering pipeline and the associated 56 pigging facilities and 39 block valves. The study found one underground leak accounting for 83% (4.0 kg CH4/hr of total measured emissions. Methane emissions for the 4684 km of gathering pipeline in the study area were estimated at 402 kg CH4/hr [95 to 1065 kg CH4/hr, 95% CI], or 1% [0.2% to 2.6%] of all methane emissions measured during a prior aircraft study of the same area. Emissions estimated by this study fall within the uncertainty range of emissions estimated using emission factors from EPA’s 2015 Greenhouse Inventory and study activity estimates. While EPA’s current inventory is based upon emission factors from distribution mains measured in the 1990s, this study indicates that using emission factors from more recent distribution studies could significantly underestimate emissions from gathering pipelines. To guide broader studies of pipeline emissions, we also estimate the fraction of the pipeline length within a basin that must be measured to constrain uncertainty of pipeline emissions estimates to within 1% of total basin emissions. The study provides both substantial insight into the mix of emission sources and guidance for future gathering pipeline studies, but since measurements were made in a single basin, the results are not sufficiently representative to provide methane emission factors at the regional or national level.

  1. An energy-efficient failure detector for vehicular cloud computing.

    Science.gov (United States)

    Liu, Jiaxi; Wu, Zhibo; Dong, Jian; Wu, Jin; Wen, Dongxin

    2018-01-01

    Failure detectors are one of the fundamental components for maintaining the high availability of vehicular cloud computing. In vehicular cloud computing, lots of RSUs are deployed along the road to improve the connectivity. Many of them are equipped with solar battery due to the unavailability or excess expense of wired electrical power. So it is important to reduce the battery consumption of RSU. However, the existing failure detection algorithms are not designed to save battery consumption RSU. To solve this problem, a new energy-efficient failure detector 2E-FD has been proposed specifically for vehicular cloud computing. 2E-FD does not only provide acceptable failure detection service, but also saves the battery consumption of RSU. Through the comparative experiments, the results show that our failure detector has better performance in terms of speed, accuracy and battery consumption.

  2. Vehicular ad hoc networks standards, solutions, and research

    CERN Document Server

    Molinaro, Antonella; Scopigno, Riccardo

    2015-01-01

    This book presents vehicular ad-hoc networks (VANETs) from the their onset, gradually going into technical details, providing a clear understanding of both theoretical foundations and more practical investigation. The editors gathered top-ranking authors to provide comprehensiveness and timely content; the invited authors were carefully selected from a list of who’s who in the respective field of interest: there are as many from Academia as from Standardization and Industry sectors from around the world. The covered topics are organized around five Parts starting from an historical overview of vehicular communications and standardization/harmonization activities (Part I), then progressing to the theoretical foundations of VANETs and a description of the day-one standard-compliant solutions (Part II), hence going into details of vehicular networking and security (Part III) and to the tools to study VANETs, from mobility and channel models, to network simulators and field trial methodologies (Part IV), and fi...

  3. Cognitive radio application for vehicular ad hoc networks (VANETS

    Directory of Open Access Journals (Sweden)

    Miladić Suzana D.

    2016-01-01

    Full Text Available This paper presents the application of cognitive radio technology in vehicular ad-hoc networks aimed to improve the communications between vehicles themselves as well as between vehicles and roadside infrastructure. Due to dynamic approach of spectrum access, cognitive radio is a technology that enables more efficient usage of radio-frequency spectrum. We review actual approaches and discuss research challenges related to the use of cognitive radio technology in vehicular ad hoc networks with emphasis on architecture, spectrum management as well as QoS optimization. The researching on cognitive radio application in vehicular networks is still developing and there are not many experimental platforms due to their complex setups. Some related research projects and cognitive radio realizations are provided in this paper.

  4. Measurement and model of the infrared two-photon emission spectrum of GaAs.

    Science.gov (United States)

    Hayat, Alex; Ginzburg, Pavel; Orenstein, Meir

    2009-07-10

    Two-photon emission from semiconductors was recently observed, but not fully interpreted. We develop a dressed-state model incorporating intraband scattering-related level broadening, yielding nondivergent emission rates. The spectrum calculations for high carrier concentrations including the time dependence of the screening buildup correspond well to our measured two-photon emission spectrum from GaAs.

  5. Nitrous oxide emissions from a beech forest floor measured by eddy covariance and soil enclosure techniques

    DEFF Research Database (Denmark)

    Pihlatie, M.; Rinne, J.; Ambus, P.

    2005-01-01

    Spring time nitrous oxide (N2O) emissions from an old beech (Fagus sylvatica L.) forest were measured with eddy covariance (EC) and chamber techniques. The aim was to obtain information on the spatial and temporal variability in N2O emissions and link the emissions to soil environmental parameters...

  6. Gamma-ray emission profile measurements during JET ICRH discharges

    Energy Technology Data Exchange (ETDEWEB)

    Howarth, P.J.A. [Birmingham Univ. (United Kingdom); Adams, J.M.; Bond, D.S.; Watkins, N. [AEA Technology, Harwell (United Kingdom); Jarvis, O.N.; Marcus, F.B.; Sadler, G.; Belle, P. van [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-12-31

    Ion Cyclotron Resonant Heating (ICRH) that is tuned to minority fuel ions can induce an energy diffusion of the heated species and create high energy tail temperatures of {approx} 1 MeV. The most energetic of these accelerated minority ions can undergo nuclear reactions with impurity Be and C that produces {gamma}-ray emission from the decay of the excited product nuclei. This RF-induced {gamma}-ray emission has been recorded using the JET neutron emission profile diagnostic which is capable of distinguishing neutrons and {gamma}-rays. Appropriate data processing has enabled the RF-induced {gamma}-ray emission signals to be isolated from the {gamma}-ray emission signals associated with neutron interactions in the material surrounding the profile monitor. The 2-d {gamma}-ray emission profiles show that virtually all the radiation originates from the low field side of the RF resonance layer, as expected from RF-induced pitch angle diffusion. The emission profiles indicate the presence of a small population of resonant {sup 3}He ions that possess orbits lying near the passing-trapped boundary. (author) 6 refs., 4 figs.

  7. Reliable vehicular broadcast using 5G device-to-device communication

    NARCIS (Netherlands)

    Gholibeigi, Mozhdeh; Sarrionandia, Nora; Karimzadeh Motallebi Azar, Morteza; Baratchi, Mitra; van den Berg, Hans Leo; Heijenk, Geert

    2017-01-01

    With the ever-increasing call for connected vehicles and intelligent transportation applications, vehicular networking have been of significant focus recently. Demands for highly reliable communication challenge the current underlying technology and transformations in vehicular communication are

  8. Evaluation of mobile emissions contributions to Mexico City's emissions inventory using on-road and cross-road emission measurements and ambient data

    Science.gov (United States)

    Zavala, M.; Herndon, S. C.; Wood, E. C.; Onasch, T. B.; Knighton, W. B.; Marr, L. C.; Kolb, C. E.; Molina, L. T.

    2009-09-01

    Mobile emissions represent a significant fraction of the total anthropogenic emissions burden in the Mexico City Metropolitan Area (MCMA) and, therefore, it is crucial to use top-down techniques informed by on-road exhaust measurements to evaluate and improve traditional bottom-up official emissions inventory (EI) for the city. We present the measurements of on-road fleet-average emission factors obtained using the Aerodyne mobile laboratory in the MCMA in March 2006 as part of the MILAGRO/MCMA-2006 field campaign. A comparison of our on-road emission measurements with those obtained in 2003 using essentially the same measurement techniques and analysis methods indicates that, in the three year span, NO emission factors remain within the measured variability ranges whereas emission factors of aldehydes and aromatics species were reduced for all sampled driving conditions. We use a top-down fuel-based approach to evaluate the mobile emissions from the gasoline fleet estimated in the bottom-up official 2006 MCMA mobile sources. Within the range of measurement uncertainties, we found probable slight overpredictions of mean EI estimates on the order of 20-28% for CO and 14-20% for NO. However, we identify a probable EI discrepancy of VOC mobile emissions between 1.4 and 1.9; although estimated benzene and toluene mobile emissions in the inventory seem to be well within the uncertainties of the corresponding emissions estimates. Aldehydes mobile emissions in the inventory, however, seem to be underpredicted by factors of 3 for HCHO and 2 for CH3CHO. Our on-road measurement-based estimate of annual emissions of organic mass from PM1 particles suggests a severe underprediction (larger than a factor of 4) of PM2.5 mobile emissions in the inventory. Analyses of ambient CO, NOx and CO/NOx concentration trends in the MCMA indicate that the early morning ambient CO/NOx ratio has decreased at a rate of about 1.9 ppm/ppm/year over the last two decades due to reductions in CO

  9. Study on Emission Measurement of Vehicle on Road Based on Binomial Logit Model

    OpenAIRE

    Aly, Sumarni Hamid; Selintung, Mary; Ramli, Muhammad Isran; Sumi, Tomonori

    2011-01-01

    This research attempts to evaluate emission measurement of on road vehicle. In this regard, the research develops failure probability model of vehicle emission test for passenger car which utilize binomial logit model. The model focuses on failure of CO and HC emission test for gasoline cars category and Opacity emission test for diesel-fuel cars category as dependent variables, while vehicle age, engine size, brand and type of the cars as independent variables. In order to imp...

  10. Studies on urban vehicular ad-hoc networks

    CERN Document Server

    Zhu, Hongzi

    2013-01-01

    With the advancement of wireless technology, vehicular ad hoc networks (VANETs) are emerging as a promising approach to realizing 'smart cities' and addressing many important transportation problems such as road safety, efficiency, and convenience.This brief provides an introduction to the large trace data set collected from thousands of taxis and buses in Shanghai, the largest metropolis in China. It also presents the challenges, design issues, performance modeling and evaluation of a wide spectrum of VANET research topics, ranging from realistic vehicular mobility models and opportunistic ro

  11. Effects of diurnal emission patterns and sampling frequency on precision of measurement methods for daily ammonia emissions from animal houses

    NARCIS (Netherlands)

    Estelles, F.; Calvet, S.; Ogink, N.W.M.

    2010-01-01

    Ammonia concentrations and airflow rates are the main parameters needed to determine ammonia emissions from animal houses. It is possible to classify their measurement methods into two main groups according to the sampling frequency: semi-continuous and daily average measurements. In the first

  12. Acoustic Emission Measurements for Tool Wear Evaluation in Drilling

    Science.gov (United States)

    Gómez, Martín P.; Migliori, Julio; Ruzzante, José E.; D'Attellis, Carlos E.

    2009-03-01

    In this work, the tool condition in a drilling process of SAE 1040 steel samples was studied by means of acoustic emission. The studied drill bits were modified with artificial and real failures, such as different degrees of wear in the cutting edge and in the outer corner. Some correlation between mean power of the acoustic emission parameters and the drill bit wear condition was found.

  13. Measuring Greenhouse Gas Emissions and Sinks Across California Land Cover

    Science.gov (United States)

    Fischer, M. L.

    2017-12-01

    Significant reductions in greenhouse gas (GHG) emissions are needed to limit rising planetary temperatures that will otherwise limit Earth's capacity to support life, introducing geopolitical instability. To help mitigate this threat, California has legislated landmark reductions in state-level greenhouse gas (GHG) emissions that set an example for broader action. Beginning with relatively assured reduction of current emissions to 1990 levels by 2020, future goals are much more challenging with 40% and 80% reductions below 1990 emissions by 2030 and 2050, respectively. While the majority of the reductions must focus on fossil fuels, inventory estimates of non-CO2 GHG emissions (i.e., CH4, N2O, and industrial compounds) constitute 15% of the total, suggesting reductions are required across multiple land use sectors. However, recent atmospheric inversion studies show methane and nitrous oxide (CH4 & N2O) emissions exceed current inventory estimates by factors of 1.2-1.8 and 1.6-2.6 (at 95% confidence), respectively, perhaps constituting up to 30% of State total emissions. The discrepancy is likely because current bottom-up models used for inventories do not accurately capture important management or biophysical factors. In the near term, process level experiments and sector-specific inversions are being planned to quantify the factors controlling non-CO2 GHG emissions for several of the dominant emission sectors. For biosphere carbon, California forests lands, which also depend on the combination of management, climate, and weather, lost above ground carbon from 2001-2010, and may be expected to lose soil and root carbon as a longer-term result. Here, it is important to identify and apply the best principles in forestry and agriculture to increase carbon stocks in depleted forest and agricultural areas, focusing on approaches that provide resilience to future climate and weather variations. Taken together, improved atmospheric, plant, and soil observations, together

  14. Airborne measurements of isoprene and monoterpene emissions from southeastern U.S. forests

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Haofei; Guenther, Alex; Gu, Dasa; Warneke, Carsten; Geron, Chris; Goldstein, Allen; Graus, Martin; Karl, Thomas; Kaser, Lisa; Misztal, Pawel; Yuan, Bin

    2017-10-01

    Isoprene and monoterpene emission rates are essential inputs for atmospheric chemistry models that simulate atmospheric oxidant and particle distributions. Process studies of the biochemical and physiological mechanisms controlling these emissions are advancing our understanding and the accuracy of model predictions but efforts to quantify regional emissions have been limited by a lack of constraints on regional distributions of ecosystem emission capacities. We used an airborne wavelet-based eddy covariance measurement technique to characterize isoprene and monoterpene fluxes with high spatial resolution during the 2013 SAS (Southeast Atmosphere Study) in the southeastern United States. The fluxes measured by direct eddy covariance were comparable to emissions independently estimated using an indirect inverse modeling approach. Isoprene emission factors based on the aircraft wavelet flux estimates for high isoprene chemotypes (e.g., oaks) were similar to the MEGAN2.1 biogenic emission model estimates for landscapes dominated by oaks. Aircraft flux measurement estimates for landscapes with fewer isoprene emitting trees (e.g., pine plantations), were about a factor of two lower than MEGAN2.1 model estimates. The tendency for high isoprene emitters in these landscapes to occur in the shaded understory, where light dependent isoprene emissions are diminished, may explain the lower than expected emissions. This result demonstrates the importance of accurately representing the vertical profile of isoprene emitting biomass in biogenic emission models. Airborne measurement-based emission factors for high monoterpene chemotypes agreed with MEGAN2.1 in landscapes dominated by pine (high monoterpene chemotype) trees but were more than a factor of three higher than model estimates for landscapes dominated by oak (relatively low monoterpene emitting) trees. This results suggests that unaccounted processes, such as floral emissions or light dependent monoterpene emissions, or

  15. Airborne measurements of isoprene and monoterpene emissions from southeastern U.S. forests.

    Science.gov (United States)

    Yu, Haofei; Guenther, Alex; Gu, Dasa; Warneke, Carsten; Geron, Chris; Goldstein, Allen; Graus, Martin; Karl, Thomas; Kaser, Lisa; Misztal, Pawel; Yuan, Bin

    2017-10-01

    Isoprene and monoterpene emission rates are essential inputs for atmospheric chemistry models that simulate atmospheric oxidant and particle distributions. Process studies of the biochemical and physiological mechanisms controlling these emissions are advancing our understanding and the accuracy of model predictions but efforts to quantify regional emissions have been limited by a lack of constraints on regional distributions of ecosystem emission capacities. We used an airborne wavelet-based eddy covariance measurement technique to characterize isoprene and monoterpene fluxes with high spatial resolution during the 2013 SAS (Southeast Atmosphere Study) in the southeastern United States. The fluxes measured by direct eddy covariance were comparable to emissions independently estimated using an indirect inverse modeling approach. Isoprene emission factors based on the aircraft wavelet flux estimates for high isoprene chemotypes (e.g., oaks) were similar to the MEGAN2.1 biogenic emission model estimates for landscapes dominated by oaks. Aircraft flux measurement estimates for landscapes with fewer isoprene emitting trees (e.g., pine plantations), were about a factor of two lower than MEGAN2.1 model estimates. The tendency for high isoprene emitters in these landscapes to occur in the shaded understory, where light dependent isoprene emissions are diminished, may explain the lower than expected emissions. This result demonstrates the importance of accurately representing the vertical profile of isoprene emitting biomass in biogenic emission models. Airborne measurement-based emission factors for high monoterpene chemotypes agreed with MEGAN2.1 in landscapes dominated by pine (high monoterpene chemotype) trees but were more than a factor of three higher than model estimates for landscapes dominated by oak (relatively low monoterpene emitting) trees. This results suggests that unaccounted processes, such as floral emissions or light dependent monoterpene emissions, or

  16. Apparatus to measure emissivities of metallic films between 90K and room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bekeris, V I [Nunez Univ. Nacional (Argentina). Faculdad de Ciencias Exactas Y Naturales; Ramos, E D [Santa Rosa Univ. Nacional (Argentina). Facultad de Ciencias Exactas Y Naturales; Sanchez, D H [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    1975-09-01

    The development of multilayer insulations is aerospace and cryogenic required to know the emissivity of the metallic films used as reflective layers. This work describes an emissometer that measures the total hemispherical emissivity of metallic films evaporated on polyester substrates. The apparatus works at liquid oxigen temperatures and permits to get emissivities from 90K to room temperatures within a 15% precision. The emissometer construction and operation are described in detail. Results of measurements done on Single Aluminized Mylar are presented.

  17. Apparatus to measure emissivities of metallic films between 90K and room temperature

    International Nuclear Information System (INIS)

    Bekeris, V.I.; Ramos, E.D.; Sanchez, D.H.

    1975-01-01

    The development of multilayer insulations is aerospace and cryogenic required to know the emissivity of the metallic films used as reflective layers. This work describes an emissometer that measures the total hemispherical emissivity of metallic films evaporated on polyester substrates. The apparatus works at liquid oxigen temperatures and permits to get emissivities from 90K to room temperatures within a 15% precision. The emissometer construction and operation are described in detail. Results of measurements done on Single Aluminized Mylar are presented [pt

  18. Doses due to extra-vehicular activity on space stations

    Energy Technology Data Exchange (ETDEWEB)

    Deme, S.; Apathy, I.; Feher, I. [KFKI Atomic Energy Research Institute, Budapest (Hungary); Akatov, Y.; Arkhanguelski, V. [Institute of Biomedical Problems, State Scientific Center, Moscow (Russian Federation); Reitz, G. [DLR Institute of Aerospace Medicine, Cologne, Linder Hohe (Germany)

    2006-07-01

    One of the many risks of long duration space flight is the dose from cosmic radiation, especially during periods of intensive solar activity. At such times, particularly during extra-vehicular activity (E.V.A.), when the astronauts are not protected by the wall of the spacecraft, cosmic radiation is a potentially serious health threat. Accurate dose measurement becomes increasingly important during the assembly of large space objects. Passive integrating detector systems such as thermoluminescent dosimeters (TLDs) are commonly used for dosimetric mapping and personal dosimetry on space vehicles. K.F.K.I. Atomic Energy Research Institute has developed and manufactured a series of thermoluminescent dosimeter systems, called Pille, for measuring cosmic radiation doses in the 3 {mu}Gy to 10 Gy range, consisting of a set of CaSO{sub 4}:Dy bulb dosimeters and a small, compact, TLD reader suitable for on-board evaluation of the dosimeters. Such a system offers a solution for E.V.A. dosimetry as well. By means of such a system, highly accurate measurements were carried out on board the Salyut-6, -7 and Mir Space Stations, on the Space Shuttle, and most recently on several segments of the International Space Station (I.S.S.). The Pille system was used to make the first measurements of the radiation exposure of cosmonauts during E.V.A.. Such E.V.A. measurements were carried out twice (on June 12 and 16, 1987) by Y. Romanenko, the commander of the second crew of Mir. During the E.V.A. one of the dosimeters was fixed in a pocket on the outer surface of the left leg of his space-suit; a second dosimeter was located inside the station for reference measurements. The advanced TLD system Pille 96 was used during the Nasa-4 (1997) mission to monitor the cosmic radiation dose inside the Mir Space Station and to measure the exposure of two of the astronauts during their E.V.A. activities. The extra doses of two E.V.A. during the Euromir 95 and one E.V.A. during the Nasa4 experiment

  19. Doses due to extra-vehicular activity on space stations

    International Nuclear Information System (INIS)

    Deme, S.; Apathy, I.; Feher, I.; Akatov, Y.; Arkhanguelski, V.; Reitz, G.

    2006-01-01

    One of the many risks of long duration space flight is the dose from cosmic radiation, especially during periods of intensive solar activity. At such times, particularly during extra-vehicular activity (E.V.A.), when the astronauts are not protected by the wall of the spacecraft, cosmic radiation is a potentially serious health threat. Accurate dose measurement becomes increasingly important during the assembly of large space objects. Passive integrating detector systems such as thermoluminescent dosimeters (TLDs) are commonly used for dosimetric mapping and personal dosimetry on space vehicles. K.F.K.I. Atomic Energy Research Institute has developed and manufactured a series of thermoluminescent dosimeter systems, called Pille, for measuring cosmic radiation doses in the 3 μGy to 10 Gy range, consisting of a set of CaSO 4 :Dy bulb dosimeters and a small, compact, TLD reader suitable for on-board evaluation of the dosimeters. Such a system offers a solution for E.V.A. dosimetry as well. By means of such a system, highly accurate measurements were carried out on board the Salyut-6, -7 and Mir Space Stations, on the Space Shuttle, and most recently on several segments of the International Space Station (I.S.S.). The Pille system was used to make the first measurements of the radiation exposure of cosmonauts during E.V.A.. Such E.V.A. measurements were carried out twice (on June 12 and 16, 1987) by Y. Romanenko, the commander of the second crew of Mir. During the E.V.A. one of the dosimeters was fixed in a pocket on the outer surface of the left leg of his space-suit; a second dosimeter was located inside the station for reference measurements. The advanced TLD system Pille 96 was used during the Nasa-4 (1997) mission to monitor the cosmic radiation dose inside the Mir Space Station and to measure the exposure of two of the astronauts during their E.V.A. activities. The extra doses of two E.V.A. during the Euromir 95 and one E.V.A. during the Nasa4 experiment were

  20. 36 CFR 910.18 - Vehicular circulation and storage systems.

    Science.gov (United States)

    2010-07-01

    ... storage systems. 910.18 Section 910.18 Parks, Forests, and Public Property PENNSYLVANIA AVENUE DEVELOPMENT... storage systems. (a) Improvement of the existing vehicular storage and circulation system is necessary in order to create the balanced transportation system called for in the Plan, which recognizes the need to...

  1. Authentication and consensus overhead in vehicular ad hoc networks

    NARCIS (Netherlands)

    Petit, Jonathan; Mammeri, Zoubir

    Vehicular ad hoc networks aim at increasing passenger safety by exchanging warning messages between vehicles wirelessly. A main challenge is to resist to various malicious abuses and security attacks. However, any security mechanism comes with overhead. We analyze how the authentication algorithm

  2. Resilient In-Network Aggregation for Vehicular Networks

    NARCIS (Netherlands)

    Dietzel, Stefan

    2015-01-01

    Applications for vehicular ad hoc networks (VANETs) are an active field of re- search with the potential to significantly contribute to driver safety, traffic efficiency, and comfort. Messages are typically exchanged and forwarded between vehicles using wireless communication, thereby creating a

  3. Comparing alertness and injury severity following motor vehicular ...

    African Journals Online (AJOL)

    Background: From casual observation of injury patterns in Motor Vehicular Accidents (MVAs), it was sometimes observed that if the victim had been more alert and reacts protectively, injury severity might be reduced. Protective response is often expected to minimize the severity of injuries. Objective: To determine the ...

  4. A Survey on Infrastructure-Based Vehicular Networks

    Directory of Open Access Journals (Sweden)

    Cristiano M. Silva

    2017-01-01

    Full Text Available The infrastructure of vehicular networks plays a major role in realizing the full potential of vehicular communications. More and more vehicles are connected to the Internet and to each other, driving new technological transformations in a multidisciplinary way. Researchers in automotive/telecom industries and academia are joining their effort to provide their visions and solutions to increasingly complex transportation systems, also envisioning a myriad of applications to improve the driving experience and the mobility. These trends pose significant challenges to the communication systems: low latency, higher throughput, and increased reliability have to be granted by the wireless access technologies and by a suitable (possibly dedicated infrastructure. This paper presents an in-depth survey of more than ten years of research on infrastructures, wireless access technologies and techniques, and deployment that make vehicular connectivity available. In addition, we identify the limitations of present technologies and infrastructures and the challenges associated with such infrastructure-based vehicular communications, also highlighting potential solutions.

  5. Time interval measurement between two emissions: Ar + Au

    International Nuclear Information System (INIS)

    Bizard, G.; Bougault, R.; Brou, R.; Buta, A.; Durand, D.; Genoux-Lubain, A.; Hamdani, T.; Horn, D.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Louvel, M.; Peter, J.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.

    1998-01-01

    The Ar + Au system was studied at two bombarding energies, 30 and 60 A.MeV. The comparison of the distributions of fragment emission angles in central collisions was carried out by means of a simulation allowing the emission time interval variation. It was found that this interval depends on the bombarding energy (i.e. deposed excitation energy).For 30 A.MeV this interval is 500 fm/c (0.33 · 10 -23 s), while for 60 A.MeV it is so short that the multifragmentation concept can be used

  6. Field test of available methods to measure remotely SOx and NOx emissions from ships

    NARCIS (Netherlands)

    Balzani Lööv, J.M.; Alfoldy, B.; Gast, L.F.L.; Hjorth, J.; Lagler, F.; Mellqvist, J.; Beecken, J.; Berg, N.; Duyzer, J.; Westrate, H.; Swart, D.P.J.; Berkhout, A.J.C.; Jalkanen, J.P.; Prata, A.J.; Van Der Hoff, G.R.; Borowiak, A.

    2014-01-01

    Methods for the determination of ship fuel sulphur content and NOx emission factors based on remote measurements have been compared in the harbour of Rotterdam and compared to direct stack emission measurements on the ferry Stena Hollandica. The methods were selected based on a review of the

  7. Estimating air emissions from a remediation of a petroleum sump using direct measurement and modeling

    International Nuclear Information System (INIS)

    Schmidt, C.E.

    1991-01-01

    A technical approach was developed for the remediation of a petroleum sump near a residential neighborhood. The approach evolved around sludge handling/in-situ solidification and on-site disposal. As part of the development of the engineering approach, a field investigation and modeling program was conducted to predict air emissions from the proposed remediation. Field measurements using the EPA recommended surface isolation flux chamber were conducted to represent each major activity or air exposure involving waste at the site. Air emissions from freshly disturbed petroleum waste, along with engineering estimates were used to predict emissions from each phase of the engineering approach. This paper presents the remedial approach and the measurement/modeling technologies used to predict air toxic emissions from the remediation. Emphasis will be placed on the measurement approaches used in obtaining the emission rate data and the assumptions used in the modeling to estimate emissions from engineering scenarios

  8. Measurements of N2O emissions at the landscape scale

    DEFF Research Database (Denmark)

    Schelde, Kirsten; Cellier, P.; Bertolini, T.

    2011-01-01

    Nitrous oxide emissions from agricultural land are variable at the landscape scale due to variability in land use, management, soil type, and topography. A field experiment was carried out in a typical mixed farming landscape near Bjerringbro, Denmark, to investigate the main sources of variations...

  9. Methods for Measuring and Estimating Methane Emission from Ruminants

    Directory of Open Access Journals (Sweden)

    Jørgen Madsen

    2012-04-01

    Full Text Available This paper is a brief introduction to the different methods used to quantify the enteric methane emission from ruminants. A thorough knowledge of the advantages and disadvantages of these methods is very important in order to plan experiments, understand and interpret experimental results, and compare them with other studies. The aim of the paper is to describe the principles, advantages and disadvantages of different methods used to quantify the enteric methane emission from ruminants. The best-known methods: Chambers/respiration chambers, SF6 technique and in vitro gas production technique and the newer CO2 methods are described. Model estimations, which are used to calculate national budget and single cow enteric emission from intake and diet composition, are also discussed. Other methods under development such as the micrometeorological technique, combined feeder and CH4 analyzer and proxy methods are briefly mentioned. Methods of choice for estimating enteric methane emission depend on aim, equipment, knowledge, time and money available, but interpretation of results obtained with a given method can be improved if knowledge about the disadvantages and advantages are used in the planning of experiments.

  10. Measurement of acoustic emission signal energy. Calibration and tests

    International Nuclear Information System (INIS)

    Chretien, N.; Bernard, P.; Fayolle, J.

    1975-01-01

    The possibility of using an Audimat W device for analyzing the electric energy of signals delivered by a piezo-electric sensor for acoustic emission was investigated. The characteristics of the prototype device could be improved. The tests performed revealed that the 7075-T651 aluminium alloy can be used as a reference material [fr

  11. Characterization of the emissions impacts of hybrid excavators with a portable emissions measurement system (PEMS)-based methodology.

    Science.gov (United States)

    Cao, Tanfeng; Russell, Robert L; Durbin, Thomas D; Cocker, David R; Burnette, Andrew; Calavita, Joseph; Maldonado, Hector; Johnson, Kent C

    2018-04-13

    Hybrid engine technology is a potentially important strategy for reduction of tailpipe greenhouse gas (GHG) emissions and other pollutants that is now being implemented for off-road construction equipment. The goal of this study was to evaluate the emissions and fuel consumption impacts of electric-hybrid excavators using a Portable Emissions Measurement System (PEMS)-based methodology. In this study, three hybrid and four conventional excavators were studied for both real world activity patterns and tailpipe emissions. Activity data was obtained using engine control module (ECM) and global positioning system (GPS) logged data, coupled with interviews, historical records, and video. This activity data was used to develop a test cycle with seven modes representing different types of excavator work. Emissions data were collected over this test cycle using a PEMS. The results indicated the HB215 hybrid excavator provided a significant reduction in tailpipe carbon dioxide (CO 2 ) emissions (from -13 to -26%), but increased diesel particulate matter (PM) (+26 to +27%) when compared to a similar model conventional excavator over the same duty cycle. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Estimation of intersubject variability of cerebral blood flow measurements using MRI and positron emission tomography

    DEFF Research Database (Denmark)

    Henriksen, Otto Mølby; Larsson, Henrik B W; Hansen, Adam E

    2012-01-01

    PURPOSE: To investigate the within and between subject variability of quantitative cerebral blood flow (CBF) measurements in normal subjects using various MRI techniques and positron emission tomography (PET). MATERIALS AND METHODS: Repeated CBF measurements were performed in 17 healthy, young...

  13. Methods for measurements of energy and emissions related to motor vehicles: Identification of needs for improvements

    Energy Technology Data Exchange (ETDEWEB)

    Karl-Erik Egebaeck, K.E. [Luleaa Univ. of Technology, Luleaa (Sweden). Dept. of Environmental Technology; Karlsson, Hua L. [MTC AB, Haninge (Sweden); Westerholm, R. [Stockholm Univ. (Sweden). Dept. of Analytical Chemistry

    2002-01-01

    The official methods in use today for emission testing of vehicles and engines were primarily developed for the characterisation of exhaust emissions from motor vehicles fuelled with petrol or diesel oil. The setting of new lower emission standards will make it difficult to obtain sufficient accuracy, using the present systems, for the quantification of exhaust emissions in the future. Development of new emission control technology and improved fuels has made it possible to meet these more stringent standards. Consequently new emission standards will lead to a need for new and improved methodologies and new instrumentation for the characterisation of the emissions from vehicles/engines/fuels. The present report comprises a discussion and comments on questions related to improved methods for emission measurements. The report is based on a study of the literature, site visits to laboratories and research institutes etc in the US and a meeting with representatives of the EU Commission, carried out during the spring of 2001. The conclusions and recommendations in the pre-study report are summarised in sub titles: General, regulated emissions, unregulated emissions, greenhouse gases and fuel consumption. Since the questions and problems discussed have an international connection they should be discussed in an international forum. However, before such discussions can be organised the problems related to measurement of emissions and fuel consumption must be more extensively studied than in this pre-study.

  14. Particulate matter emission from livestock houses: measurement methods, emission levels and abatement systems

    NARCIS (Netherlands)

    Winkel, Albert

    2016-01-01

    Animal houses are extremely dusty environments. Airborne particulate matter (PM) poses a health threat not only to the farmer and the animals, but, as a result of emissions from ventilation systems, also to residents living in livestock farming areas. In relation to this problem, the objectives

  15. Annual cycle of methane emission from a boreal fen measured by the eddy covariance technique

    International Nuclear Information System (INIS)

    Rinne, Janne.; Pihlatie, Mari; Haapanala, Sami; Vesala, Timo; Riutta, Terhi; Tuittila, Eeva-Stiina; Aurela, Mika; Tuovinen, Juha-Pekka

    2007-01-01

    The northern wetlands are one of the major sources of methane into the atmosphere. We measured annual methane emission from a boreal minerotrophic fen, Siikaneva, by the eddy covariance method. The average wintertime emissions were below 1 mg/m 2 /h, and the summertime emissions about 3.5 mg/m 2 /h. The water table depth did have any clear effect on methane emissions. During most of the year the emission depended on the temperature of peat below the water table. However, during the high and late summer the emission was independent on peat temperature as well. No diurnal cycle of methane flux was found. The total annual emission from the Siikaneva site was 12.6 g/m 2 . The emissions of the snow free period contributed 91% to the annual emission. The emission pulse during the snow melting period was clearly detectable but of minor importance adding only less than 3% to the annual emission. Over 20% of the carbon assimilated during the year as carbon dioxide was emitted as methane. Thus methane emission is an important component of the carbon balance of the Siikaneva fen. This indicates need of taking methane into account when studying carbon balances of northern fen ecosystems

  16. Emission Characteristics of Gas-Fired Boilers based on Category-Specific Emission Factor from Field Measurements in Beijing, China

    Science.gov (United States)

    Itahashi, S.; Yan, X.; Song, G.; Yan, J.; Xue, Y.

    2017-12-01

    Gas-fired boilers will become the main stationary sources of NOx in Beijing. However, the knowledge of gas-fired boilers in Beijing is limited. In the present study, the emission characteristics of NOx, SO2, and CO from gas-fired boilers in Beijing were established using category-specific emission factors (EFs) from field measurements. In order to obtain category-specific EFs, boilers were classified through influence analysis. Factors such as combustion mode, boiler type, and installed capacity were considered critical for establishing EFs because they play significant roles in pollutant formation. The EFs for NOx, CO, and SO2 ranged from 1.42-6.86 g m-3, 0.05-0.67 g m-3 and 0.03-0.48 g m-3. The emissions of NOx, SO2, and CO for gas-fired boilers in Beijing were 11121 t, 468 t, and 222 t in 2014, respectively. The emissions were spatially allocated into grid cells with a resolution of 1 km × 1 km, and the results indicated that top emitters were in central Beijing. The uncertainties were quantified using a Monte Carlo simulation. The results indicated high uncertainties in CO (-157% to 154%) and SO2 (-127% to 182%) emissions, and relatively low uncertainties (-34% to 34%) in NOx emission. Furthermore, approximately 61.2% and 96.8% of the monitored chamber combustion boilers (CCBs) met the standard limits for NOx and SO2, respectively. Concerning NOx, low-NOx burners and NOx emission control measures are urgently needed for implementing of stricter standards. Adopting terminal control measures is unnecessary for SO2, although its concentration occasionally exceeds standard limits, because reduction of its concentration can be achieved thorough control of the sulfur content of natural gas at a stable low level. Furthermore, the atmospheric combustion boilers (ACBs) should be substituted with CCBs, because ACBs have a higher emission despite lower gross installed capacity. The results of this study will enable in understanding and controlling emissions from gas

  17. Spatially resolved flux measurements of NOx from London suggest significantly higher emissions than predicted by inventories.

    Science.gov (United States)

    Vaughan, Adam R; Lee, James D; Misztal, Pawel K; Metzger, Stefan; Shaw, Marvin D; Lewis, Alastair C; Purvis, Ruth M; Carslaw, David C; Goldstein, Allen H; Hewitt, C Nicholas; Davison, Brian; Beevers, Sean D; Karl, Thomas G

    2016-07-18

    To date, direct validation of city-wide emissions inventories for air pollutants has been difficult or impossible. However, recent technological innovations now allow direct measurement of pollutant fluxes from cities, for comparison with emissions inventories, which are themselves commonly used for prediction of current and future air quality and to help guide abatement strategies. Fluxes of NOx were measured using the eddy-covariance technique from an aircraft flying at low altitude over London. The highest fluxes were observed over central London, with lower fluxes measured in suburban areas. A footprint model was used to estimate the spatial area from which the measured emissions occurred. This allowed comparison of the flux measurements to the UK's National Atmospheric Emissions Inventory (NAEI) for NOx, with scaling factors used to account for the actual time of day, day of week and month of year of the measurement. The comparison suggests significant underestimation of NOx emissions in London by the NAEI, mainly due to its under-representation of real world road traffic emissions. A comparison was also carried out with an enhanced version of the inventory using real world driving emission factors and road measurement data taken from the London Atmospheric Emissions Inventory (LAEI). The measurement to inventory agreement was substantially improved using the enhanced version, showing the importance of fully accounting for road traffic, which is the dominant NOx emission source in London. In central London there was still an underestimation by the inventory of 30-40% compared with flux measurements, suggesting significant improvements are still required in the NOx emissions inventory.

  18. Obsidian hydration profiles measured by sputter-induced optical emission.

    Science.gov (United States)

    Tsong, I S; Houser, C A; Yusef, N A; Messier, R F; White, W B; Michels, J W

    1978-07-28

    The variation of concentrations of hydrogen, sodium, potassium, lithium, calcium, magnesium, silicon, and aluminum as a function of depth in the hydration layer of obsidian artifacts has been determined by sputter-induced optical emission. The surface hydration is accompanied by dealkalization, and there is a buildup of alkaline earths, calcium and magnesium in the outermost layers. These results have clarified the phenomena underlying the obsidian hydration dating technique.

  19. Electron Bernstein Wave Coupling and Emission Measurements on NSTX

    Czech Academy of Sciences Publication Activity Database

    Taylor, G.; Diem, S.J.; Caughman, J.; Efthimion, P.; Harvey, R.W.; LeBlanc, B.P.; Philips, C.K.; Preinhaelter, Josef; Urban, Jakub

    2006-01-01

    Roč. 51, č. 7 (2006), s. 177 ISSN 0003-0503. [Annual Meeting of the Division of Plasma Physics/48th./. Philadelphia, Pennsylvania , 30.10.2006-3.11.2006] Institutional research plan: CEZ:AV0Z20430508 Keywords : Conversion * Emission * Tokamaks * Electron Bernstein waves * Simulation * MAST * NSTX Subject RIV: BL - Plasma and Gas Discharge Physics http://www.aps.org/meet/DPP06/baps/all_DPP06.pdf

  20. Thermal Electron Bernstein Wave Emission Measurements on NST

    Czech Academy of Sciences Publication Activity Database

    Diem, S.J.; Taylor, G.; Efthimion, P.; LeBlanc, B.P.; Philips, C.K.; Caughman, J.; Wilgen, J.B.; Harvey, R.W.; Preinhaelter, Josef; Urban, Jakub

    2006-01-01

    Roč. 51, č. 7 (2006), s. 134 ISSN 0003-0503. [Annual Meeting of the Division of Plasma Physics/48th./. Philadelphia, Pennsylvania , 30.10.2006-3.11.2006] Institutional research plan: CEZ:AV0Z20430508 Keywords : Conversion * Emission * Tokamaks * Electron Bernstein waves * Simulation * MAST * NSTX Subject RIV: BL - Plasma and Gas Discharge Physics http://www.aps.org/meet/DPP06/baps/all_DPP06.pdf

  1. Future needs for ship emission abatement and technical measures

    Directory of Open Access Journals (Sweden)

    Teresa ANTES

    2013-01-01

    Full Text Available The International Maritime Organization (IMO has revised air pollution regulations in MARPOL Annex VI. In 2012 Emission Control Areas (ECA will limit fuel sulphur content to 1% and from 2015 to 0.1%. NOx emissions based on ships engine speed are also reduced for new vessels (2012 & 2016. Facing this legislation, ship owners have the alternative either to operate ships with costly low-sulphur fuels, or to keep using HFO but together with a gas cleaning equipment at the ship stack in order to reduce the rejected amount of SO2 gas in the atmosphere. To achieve this requirement, research and development organizations came out with proposing a solution that uses a device for cleaning exhaust gas of marine diesel engines. The paper presents a short communication about the DEECON project, which aim is to create a novel on-board after-treatment unit more advanced than any currently available. Each sub-unit of the system will be optimized to remove a specific primary pollutant. In particular, the technology within the DEECON system is based on novel or improved abatement techniques for reducing SOx, NOx, Particulate Matter (PM, CO and Volatile Organic Compounds (VOC. Some of these technologies are completely new for the maritime sector and they will represent a breakthrough in the reduction of the atmospheric emissions of ships, moving forward the performance of exhaust gas cleaning systems and fostering and anticipating the adoption of future and tighter regulatory requirements. In addition, an after-treatment strategy enables the possible adoption of alternative fuels, which often have their own emissions characteristics.

  2. Time interval measurement between two emissions: Kr + Au

    International Nuclear Information System (INIS)

    Aboufirassi, M; Bougault, R.; Brou, R.; Colin, J.; Durand, D.; Genoux-Lubain, A.; Horn, D.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Lefebvres, F.; Lopez, O.; Louvel, M.; Mahi, M.; Steckmeyer, J.C.; Tamain, B.

    1998-01-01

    To indicate the method allowing the determination of the emission intervals, the results obtained with the Kr + Au system at 43 and 60 A.MeV are presented. The experiments were performed with the NAUTILUS exclusive detectors. Central collisions were selected by means of a relative velocity criterion to reject the events containing a forward emitted fragment. For the two bombardment energies the data analysis shows that the formation of a compound of mass around A = 200. By comparing the fragment dynamical variables with simulations one can conclude about the simultaneity of the compound deexcitation processes. It was found that a 5 MeV/A is able to reproduce the characteristics of the detected fragments. Also, it was found that to reproduce the dynamical characteristics of the fragments issued from central collisions it was not necessary to superimpose a radial collective energy upon the Coulomb and thermal motion. The distribution of the relative angles between detected fragments is used here as a chronometer. For simultaneous ruptures the small relative angles are forbidden by the Coulomb repulsion, while for sequential processes this interdiction is the more lifted the longer the interval between the two emissions is. For the system discussed here the comparison between simulation and data has been carried out for the extreme cases, i.e. for a vanishing and infinite time interval between the two emissions, respectively. More sophisticated simulations to describe angular distributions between the emitted fragments were also developed

  3. System for quantitative measurements of methane emission from dairy cattle in Denmark

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Lund, Peter; Johannes, Maike

    The methane emission from the digestive tract of cattle in Denmark accounts for 45% of the total methane emission based on the assumption that 6% of the gross energy is metabolized to methane. There is a lack of newer experimental data available for Danish cattle; therefore we have built a unit...... expectations for a system for exact measurements of methane emission in dairy cows at production level under close to natural in barn conditions, where cows’ behavior can be expected to be natural....

  4. Real-world and specific to vehicle driving cycles for measuring car pollutant emissions

    OpenAIRE

    ANDRE, M; JOUMARD, R

    2004-01-01

    In the frame of the European research project ARTEMIS, a set of representative real-world driving cycles has been developed, to ensure a coherency between the pollutant emissions measurements conducted in the frame of the ARTEMIS project and of on-going national campaigns and to enable the integration of all the resulting emission data in the European systems of emission inventory. The 3 real-world ARTEMIS driving cycles (urban, rural road and motorway) represent the observed European drivi...

  5. VOC species and emission inventory from vehicles and their SOA formation potentials estimation in Shanghai, China

    Science.gov (United States)

    Huang, C.; Wang, H. L.; Li, L.; Wang, Q.; Lu, Q.; de Gouw, J. A.; Zhou, M.; Jing, S. A.; Lu, J.; Chen, C. H.

    2015-10-01

    Volatile organic compound (VOC) species from vehicle exhausts and gas evaporation were investigated by chassis dynamometer and on-road measurements of nine gasoline vehicles, seven diesel vehicles, five motorcycles, and four gas evaporation samples. The secondary organic aerosol (SOA) mass yields of gasoline, diesel, motorcycle exhausts, and gas evaporation were estimated based on the mixing ratio of measured C2-C12 VOC species and inferred carbon number distributions. High aromatic contents were measured in gasoline exhausts and contributed comparatively more SOA yield. A vehicular emission inventory was compiled based on a local survey of on-road traffic in Shanghai and real-world measurements of vehicle emission factors from previous studies in the cities of China. The inventory-based vehicular organic aerosol (OA) productions to total CO emissions were compared with the observed OA to CO concentrations (ΔOA / ΔCO) in the urban atmosphere. The results indicate that vehicles dominate the primary organic aerosol (POA) emissions and OA production, which contributed about 40 and 60 % of OA mass in the urban atmosphere of Shanghai. Diesel vehicles, which accounted for less than 20 % of vehicle kilometers of travel (VKT), contribute more than 90 % of vehicular POA emissions and 80-90 % of OA mass derived by vehicles in urban Shanghai. Gasoline exhaust could be an important source of SOA formation. Tightening the limit of aromatic content in gasoline fuel will be helpful to reduce its SOA contribution. Intermediate-volatile organic compounds (IVOCs) in vehicle exhausts greatly contribute to SOA formation in the urban atmosphere of China. However, more experiments need to be conducted to determine the contributions of IVOCs to OA pollution in China.

  6. A Lightweight Radio Propagation Model for Vehicular Communication in Road Tunnels.

    Directory of Open Access Journals (Sweden)

    Muhammad Ahsan Qureshi

    Full Text Available Radio propagation models (RPMs are generally employed in Vehicular Ad Hoc Networks (VANETs to predict path loss in multiple operating environments (e.g. modern road infrastructure such as flyovers, underpasses and road tunnels. For example, different RPMs have been developed to predict propagation behaviour in road tunnels. However, most existing RPMs for road tunnels are computationally complex and are based on field measurements in frequency band not suitable for VANET deployment. Furthermore, in tunnel applications, consequences of moving radio obstacles, such as large buses and delivery trucks, are generally not considered in existing RPMs. This paper proposes a computationally inexpensive RPM with minimal set of parameters to predict path loss in an acceptable range for road tunnels. The proposed RPM utilizes geometric properties of the tunnel, such as height and width along with the distance between sender and receiver, to predict the path loss. The proposed RPM also considers the additional attenuation caused by the moving radio obstacles in road tunnels, while requiring a negligible overhead in terms of computational complexity. To demonstrate the utility of our proposed RPM, we conduct a comparative summary and evaluate its performance. Specifically, an extensive data gathering campaign is carried out in order to evaluate the proposed RPM. The field measurements use the 5 GHz frequency band, which is suitable for vehicular communication. The results demonstrate that a close match exists between the predicted values and measured values of path loss. In particular, an average accuracy of 94% is found with R2 = 0.86.

  7. Time horizon for AFV emission savings under Tier 2

    International Nuclear Information System (INIS)

    Saricks, C. L.

    2000-01-01

    Implementation of the Federal Tier 2 vehicular emission standards according to the schedule presented in the December, 1999 Final Rule will result in substantial reductions of NMHC, CO, NO x , and fine particle emissions from motor vehicles. Currently, when compared to Tier 1 and even NLEV certification requirements, the emissions performance of automobiles and light-duty trucks powered by non-petroleum (especially, gaseous) fuels (i.e., vehicles collectively termed AFVs) enjoy measurable advantage over their gasoline- and diesel-fueled counterparts over the full Federal Test Procedure and, especially, in Bag 1 (cold start). For the lighter end of these vehicle classes, this advantage may disappear shortly after 2004 under the new standards, but should continue for a longer period (perhaps beyond 2008) for the heavier end as well as for heavy-duty vehicles relative to diesel-fueled counterparts. Because of the continuing commitment of the U.S. Department of Energy's Clean Cities coalitions to the acquisition and operation of AFVs of many types and size classes, it is important for them to know in which classes their acquisitions will remain clear relative to the petroleum-fueled counterparts they might otherwise procure. This paper provides an approximate timeline for and expected magnitude of such savings, assuming that full implementation of the Tier 2 standards covering both vehicular emissions and fuel sulfur limits proceeds on schedule. The pollutants of interest are primary ozone precursors and fine particulate matter from fuel combustion

  8. Reduction of CO2 emissions from road transport in cities impact of dynamic route guidance system on greenhouse gas emission

    CERN Document Server

    Markiewicz, Michal

    2017-01-01

    Michal Markiewicz presents the outcomes of his research regarding the influence of dynamic route guidance system on overall emission of carbon dioxide from road transport in rural areas. Sustainable transportation in smart cities is a big challenge of our time, but before electric vehicles replace vehicles that burn fossil fuels we have to think about traffic optimization methods that reduce the amount of greenhouse gas emissions. Contents Comparison of Travel Time Measurements Using Floating Car Data and Intelligent Infrastructure Integration of Cellular Automata Traffic Simulator with CO2 Emission Model Impact of Dynamic Route Guidance System on CO2 Emission Naxos Vehicular Traffic Simulator Target Groups Lecturers and students of computer science, transportation and logistics Traffic engineers The Author Dr. Michal Markiewicz defended his PhD thesis in computer science at the University of Bremen,TZI Technologie-Zentrum Informatik und Informationstechnik, Germany. Currently, he is working on commercializat...

  9. Measurement of emission diameter as a function of time on foam z- pinch plasmas

    International Nuclear Information System (INIS)

    Lazier, S.E.; Barber, T.L.; Derzon, M.S.; Kellogg, J.W.

    1996-01-01

    We have developed a streaked imaging capability to make time-resolved measurements of the emission size for low density foam z-pinches. By lens coupling visible emission from the z-pinch target to an array of fiber optics we obtained the emission profile in the visible as a function of time with radial resolution of 300 μm. To measure the emission at temperatures greater than ∼40 eV the source was slit-imaged or pin-hole imaged onto an x-ray filtered scintillator. Non-uniformities in both visible and x-ray emission were observed. We describe the diagnostics, the image unfold process, and results from the instrument for both visible and x-ray measurements

  10. Te(R,t) Measurements using Electron Bernstein Wave Thermal Emission on NSTX

    International Nuclear Information System (INIS)

    Diem, S.J.; Taylor, G.; Efthimion, P.C.; LeBlanc, B.P.; Carter, M.; Caughman, J.; Wilgen, J.B.; Harvey, R.W.; Preinhaelter, J.; Urban, J.

    2006-01-01

    The National Spherical Torus Experiment (NSTX) routinely studies overdense plasmas with n e of (1-5) x 10 19 m -3 and total magnetic field of e measurement. A significant upgrade to the previous NSTX EBW emission diagnostic to measure thermal EBW emission via the oblique B-X-O mode conversion process has been completed. The new EBW diagnostic consists of two remotely steerable, quad-ridged horn antennas, each of which is coupled to a dual channel radiometer. Fundamental (8-18 GHz) and second and third harmonic (18-40 GHz) thermal EBW emission and polarization measurements can be obtained simultaneously.

  11. Measuring the respiratory gas exchange of grazing cattle using the GreenFeed emissions monitoring system

    Science.gov (United States)

    Ruminants are a significant source of enteric methane, which has been identified as a powerful greenhouse gas that contributes to climate change. With interest in developing technologies to decrease enteric methane emission, systems are currently being developed to measure the methane emission by c...

  12. Development of the Flame Test Concept Inventory: Measuring Student Thinking about Atomic Emission

    Science.gov (United States)

    Bretz, Stacey Lowery; Murata Mayo, Ana Vasquez

    2018-01-01

    This study reports the development of a 19-item Flame Test Concept Inventory, an assessment tool to measure students' understanding of atomic emission. Fifty-two students enrolled in secondary and postsecondary chemistry courses were interviewed about atomic emission and explicitly asked to explain flame test demonstrations and energy level…

  13. Large emissions of sesquiterpenes and methyl chavicol quantified from branch enclosure measurements

    NARCIS (Netherlands)

    Bouvier-Brown, N.C.; Holzinger, R.; Palitzsch, K.; Goldstein, A.H.

    2009-01-01

    Multiple field studies have suggested chemistry within a forest canopy is poorly understood due to inadequate detection and quantification of reactive biogenic emissions, such as terpenes. To measure emission rates of terpenes at Blodgett Forest, a coniferous forest in the Sierra Nevada mountains of

  14. Comparisons of MOVES Light-duty Gasoline NOx Emission Rates with Real-world Measurements

    Science.gov (United States)

    Choi, D.; Sonntag, D.; Warila, J.

    2017-12-01

    Recent studies have shown differences between air quality model estimates and monitored values for nitrogen oxides. Several studies have suggested that the discrepancy between monitored and modeled values is due to an overestimation of NOx from mobile sources in EPA's emission inventory, particularly for light-duty gasoline vehicles. EPA's MOtor Vehicle Emission Simulator (MOVES) is an emission modeling system that estimates emissions for cars, trucks and other mobile sources at the national, county, and project level for criteria pollutants, greenhouse gases, and air toxics. Studies that directly measure vehicle emissions provide useful data for evaluating MOVES when the measurement conditions are properly accounted for in modeling. In this presentation, we show comparisons of MOVES2014 to thousands of real-world NOx emissions measurements from individual light-duty gasoline vehicles. The comparison studies include in-use vehicle emissions tests conducted on chassis dynamometer tests in support of Denver, Colorado's Vehicle Inspection & Maintenance Program and remote sensing data collected using road-side instruments in multiple locations and calendar years in the United States. In addition, we conduct comparisons of MOVES predictions to fleet-wide emissions measured from tunnels. We also present details on the methodology used to conduct the MOVES model runs in comparing to the independent data.

  15. (n,p) emission channeling measurements on ion-implanted beryllium

    CERN Multimedia

    Jakubek, J; Uher, J

    2007-01-01

    We propose to perform emission-channeling measurements using thermal neutron induced proton emission from ion-implanted $^{7}$Be. The physics questions addressed concern the beryllium doping of III-V and II-VI semiconductors and the host dependence of the electron capture half-life of $^{7}$Be.

  16. Aerosol emissions from prescribed fires in the United States: A synthesis of laboratory and aircraft measurements

    Science.gov (United States)

    A. A. May; G. R. McMeeking; T. Lee; J. W. Taylor; J. S. Craven; I. Burling; A. P. Sullivan; S. Akagi; J. L. Collett; M. Flynn; H. Coe; S. P. Urbanski; J. H. Seinfeld; R. J. Yokelson; S. M. Kreidenweis

    2014-01-01

    Aerosol emissions from prescribed fires can affect air quality on regional scales. Accurate representation of these emissions in models requires information regarding the amount and composition of the emitted species. We measured a suite of submicron particulate matter species in young plumes emitted from prescribed fires (chaparral and montane ecosystems in California...

  17. Establishment of national emission measurement activity in neighbouring areas of Finland

    Energy Technology Data Exchange (ETDEWEB)

    Aunela, L.; Larjava, K.; Jormanainen, P. [VTT Chemical Technology, Espoo (Finland). Environmental Technology; Muurinen, M. [Enemi Ltd, Lahti (Finland); Hietamaeki, M. [Ministry of the Environment, Helsinki (Finland)

    1995-12-31

    Estonia, Latvia, and Lithuania (the Baltic countries) and the Republic State of Carelia, Russia belong to the so-called nearby areas of Finland. All being part of the former Soviet Union, they are now undergoing the establishment of their own environment- managing systems. Finland has shown a great amount of interest in supporting the efforts of these areas to solve their environmental problems. In 1993 VTT started, at the request of the East European Project of the Finnish Ministry of the Environment, a four year project aiming at the establishment of national atmospheric emission measurement systems in the Baltic countries and the Republic state of Carelia (later: the counterpart countries). Proper national emission measurement systems were regarded important in order to provide reliable data on the emission situation for national and international use. The main target of the work is to raise the level of the emission measurements in the counterpart countries to the international level. Two aspects were considered to be required to achieve this goal; (1) delivery of proper emission measurement equipment, (2) training of the emission measurement personnel. It was estimated that within three to four years these counterpart countries could join the Finnish quality assurance system in emission measurements if desired. (author)

  18. Establishment of national emission measurement activity in neighbouring areas of Finland

    Energy Technology Data Exchange (ETDEWEB)

    Aunela, L; Larjava, K; Jormanainen, P [VTT Chemical Technology, Espoo (Finland). Environmental Technology; Muurinen, M [Enemi Ltd, Lahti (Finland); Hietamaeki, M [Ministry of the Environment, Helsinki (Finland)

    1996-12-31

    Estonia, Latvia, and Lithuania (the Baltic countries) and the Republic State of Carelia, Russia belong to the so-called nearby areas of Finland. All being part of the former Soviet Union, they are now undergoing the establishment of their own environment- managing systems. Finland has shown a great amount of interest in supporting the efforts of these areas to solve their environmental problems. In 1993 VTT started, at the request of the East European Project of the Finnish Ministry of the Environment, a four year project aiming at the establishment of national atmospheric emission measurement systems in the Baltic countries and the Republic state of Carelia (later: the counterpart countries). Proper national emission measurement systems were regarded important in order to provide reliable data on the emission situation for national and international use. The main target of the work is to raise the level of the emission measurements in the counterpart countries to the international level. Two aspects were considered to be required to achieve this goal; (1) delivery of proper emission measurement equipment, (2) training of the emission measurement personnel. It was estimated that within three to four years these counterpart countries could join the Finnish quality assurance system in emission measurements if desired. (author)

  19. Automatic emissive probe apparatus for accurate plasma and vacuum space potential measurements

    Science.gov (United States)

    Jianquan, LI; Wenqi, LU; Jun, XU; Fei, GAO; Younian, WANG

    2018-02-01

    We have developed an automatic emissive probe apparatus based on the improved inflection point method of the emissive probe for accurate measurements of both plasma potential and vacuum space potential. The apparatus consists of a computer controlled data acquisition card, a working circuit composed by a biasing unit and a heating unit, as well as an emissive probe. With the set parameters of the probe scanning bias, the probe heating current and the fitting range, the apparatus can automatically execute the improved inflection point method and give the measured result. The validity of the automatic emissive probe apparatus is demonstrated in a test measurement of vacuum potential distribution between two parallel plates, showing an excellent accuracy of 0.1 V. Plasma potential was also measured, exhibiting high efficiency and convenient use of the apparatus for space potential measurements.

  20. A novel field measurement method for determining fine particle and gas emissions from residential wood combustion

    Science.gov (United States)

    Tissari, Jarkko; Hytönen, Kati; Lyyränen, Jussi; Jokiniemi, Jorma

    Emission data from residential wood combustion are usually obtained on test stands in the laboratory but these measurements do not correspond to the operational conditions in the field because of the technological boundary conditions (e.g. testing protocol, environmental and draught conditions). The field measurements take into account the habitual practice of the operators and provide the more reliable results needed for emission inventories. In this study, a workable and compact method for measuring emissions from residential wood combustion in winter conditions was developed. The emissions for fine particle, gaseous and PAH compounds as well as particle composition in real operational conditions were measured from seven different appliances. The measurement technique worked well and was evidently suitable for winter conditions. It was easy and fast to use, and no construction scaffold was needed. The dilution of the sample with the combination of a porous tube diluter and an ejector diluter was well suited to field measurement. The results indicate that the emissions of total volatile organic carbon (TVOC) (17 g kg -1 (of dry wood burned)), carbon monoxide (CO) (120 g kg -1) and fine particle mass (PM 1) (2.7 g kg -1) from the sauna stove were higher than in the other measured appliances. In the masonry heaters, baking oven and stove, the emissions were 2.9-9 g kg -1 TVOC, 28-68 g kg -1 CO and 0.6-1.6 g kg -1 PM 1. The emission of 12 PAHs (PAH 12) from the sauna stove was 164 mg kg -1 and consisted mainly of PAHs with four benzene rings in their structure. PAH 12 emission from other appliances was, on average, 21 mg kg -1 and was dominated by 2-ring PAHs. These results indicate that despite the non-optimal operational practices in the field, the emissions did not differ markedly from the laboratory measurements.

  1. Emissivity-corrected power loss calibration for lock-in thermography measurements on silicon solar cells

    International Nuclear Information System (INIS)

    Kasemann, Martin; Walter, Benjamin; Meinhardt, Christoph; Ebser, Jan; Kwapil, Wolfram; Warta, Wilhelm

    2008-01-01

    This paper describes power loss calibration procedures with implemented emissivity correction. The determination of our emissivity correction matrix does neither rely on blackbody reference measurements nor on the knowledge of any sample temperatures. To describe the emissivity-corrected power calibration procedures in detail, we review the theory behind lock-in thermography and show experimentally that the lock-in signal is proportional to the power dissipation in the solar cell. Experiments show the successful application of our emissivity correction procedure, which significantly improves the informative value of lock-in thermography images and the reliability of the conclusions drawn from these images

  2. Measurement of black carbon emissions from in-use diesel-electric passenger locomotives in California

    Science.gov (United States)

    Tang, N. W.; Kirchstetter, T.; Martien, P. T.; Apte, J.

    2015-12-01

    Black carbon (BC) emission factors were measured for a California commuter rail line fleet of diesel-electric passenger locomotives (Caltrain). The emission factors are based on BC and carbon dioxide (CO2) concentrations in the exhaust plumes of passing locomotives, which were measured from pedestrian overpasses using portable analyzers. Each of the 29 locomotives in the fleet was sampled on 4-20 separate occasions at different locations to characterize different driving modes. The average emission factor expressed as g BC emitted per kg diesel consumed was 0.87 ± 0.66 g kg-1 (±1 standard deviation, n = 362 samples). BC emission factors tended to be higher for accelerating locomotives traveling at higher speeds with engines in higher notch settings. Higher fuel-based BC emission factors (g kg-1) were measured for locomotives equipped with separate "head-end" power generators (SEP-HEPs), which power the passenger cars, while higher time-based emission factors (g h-1) were measured for locomotives without SEP-HEPs, whose engines are continuously operated at high speeds to provide both head-end and propulsion power. PM10 emission factors, estimated assuming a BC/PM10 emission ratio of 0.6 and a typical power output-to-fuel consumption ratio, were generally in line with the Environmental Protection Agency's locomotive exhaust emission standards. Per passenger mile, diesel-electric locomotives in this study emit only 20% of the CO2 emitted by typical gasoline-powered light-duty vehicles (i.e., cars). However, the reduction in carbon footprint (expressed in terms of CO2 equivalents) due to CO2 emissions avoidance from a passenger commuting by train rather than car is appreciably offset by the locomotive's higher BC emissions.

  3. Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

    Science.gov (United States)

    Wang, Yang; Xing, Zhenyu; Zhao, Shuhui; Zheng, Mei; Mu, Chao; Du, Ke

    2016-03-15

    Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14 mg/kg-fuel under the speeds of 20-70 km/h, 0.05-28.95 mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. A Study on Portfolio of Domestic Policies and Measures for GHG emission Abatement

    Energy Technology Data Exchange (ETDEWEB)

    Lim, J.K. [Korea Energy Economics Institute, Euiwang (Korea)

    2001-11-01

    After the climate change negotiation reaches an agreement in COP7, the next main issue to be addressed is the way of involvement of developing countries in emission abatement commitments and the development of domestic policies and measures to achieve GHG emission reduction target. Many Annex I countries have developed and implemented policies and measures to achieve its quantified GHG emission reduction target. The purpose of this paper is to propose a portfolio of policies and measures, that is, which policies and measures Korea will have to take in preparing future commitment for GHG emission reduction as well as in strengthening mitigation of climate change. Various policies and measures can be used, such as regulations, economic instruments, and covenants, etc., but it is desirable to implement them in some portfolio, taking advantage of their characteristics. Among the possible policies and measures, this study found that economic instruments such as carbon tax and domestic emissions trading have attracted considerable interest recently due to their cost effectiveness. This study also found that, in practice, many developed countries have used these policy instruments in achieving their quantified GHG emission reduction target. In order to develop a portfolio of policies and measures, the comprehension of the features of each policy and measure and the synergetic reconciliation with other objectives than climate change is important. (author). 82 refs., 11 figs., 31 tabs.

  5. Eviction of Misbehaving and Faulty Nodes in Vehicular Networks

    OpenAIRE

    Raya, Maxim; Papadimitratos, Panagiotis; Aad, Imad; Jungels, Daniel; Hubaux, Jean-Pierre

    2007-01-01

    Vehicular Networks (VNs) are emerging, among civilian applications, as a convincing instantiation of the mobile networking technology. However, security is a critical factor and a significant challenge to be met. Misbehaving or faulty network nodes have to be detected and prevented from disrupting network operation, a problem particularly hard to address in the life-critical VN environment. Existing networks rely mainly on node certificate revocation for attacker eviction, but the lack of an ...

  6. Congestion control for vehicular delay tolerant network routing protocols

    OpenAIRE

    Oham, Chuka Finbars

    2014-01-01

    The Vehicular Delay Tolerant Network (VDTN) is a special and challenging type of the Delay Tolerant Network because of its high mobility, frequent disconnections and nodal congestion features. These challenging features make it prone to congestion which leads to a considerable amount of message drops in the network. To minimize the impact of congestion in the network, we designed and implemented the Congestion Aware Spray and Wait (CASaW) routing protocol. We varied the buffer sizes of the no...

  7. Vehicular Traffic-Related Polycyclic Aromatic Hydrocarbon Exposure and Breast Cancer Incidence: The Long Island Breast Cancer Study Project (LIBCSP).

    Science.gov (United States)

    Mordukhovich, Irina; Beyea, Jan; Herring, Amy H; Hatch, Maureen; Stellman, Steven D; Teitelbaum, Susan L; Richardson, David B; Millikan, Robert C; Engel, Lawrence S; Shantakumar, Sumitra; Steck, Susan E; Neugut, Alfred I; Rossner, Pavel; Santella, Regina M; Gammon, Marilie D

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants, known human lung carcinogens, and potent mammary carcinogens in laboratory animals. However, the association between PAHs and breast cancer in women is unclear. Vehicular traffic is a major ambient source of PAH exposure. Our study aim was to evaluate the association between residential exposure to vehicular traffic and breast cancer incidence. Residential histories of 1,508 participants with breast cancer (case participants) and 1,556 particpants with no breast cancer (control participants) were assessed in a population-based investigation conducted in 1996-1997. Traffic exposure estimates of benzo[a]pyrene (B[a]P), as a proxy for traffic-related PAHs, for the years 1960-1995 were reconstructed using a model previously shown to generate estimates consistent with measured soil PAHs, PAH-DNA adducts, and CO readings. Associations between vehicular traffic exposure estimates and breast cancer incidence were evaluated using unconditional logistic regression. The odds ratio (95% CI) was modestly elevated by 1.44 (0.78, 2.68) for the association between breast cancer and long-term 1960-1990 vehicular traffic estimates in the top 5%, compared with below the median. The association with recent 1995 traffic exposure was elevated by 1.14 (0.80, 1.64) for the top 5%, compared with below the median, which was stronger among women with low fruit/vegetable intake [1.46 (0.89, 2.40)], but not among those with high fruit/vegetable intake [0.92 (0.53, 1.60)]. Among the subset of women with information regarding traffic exposure and tumor hormone receptor subtype, the traffic-breast cancer association was higher for those with estrogen/progesterone-negative tumors [1.67 (0.91, 3.05) relative to control participants], but lower among all other tumor subtypes [0.80 (0.50, 1.27) compared with control participants]. In our population-based study, we observed positive associations between vehicular traffic

  8. Measurement of secondary emissions during laser cutting of steel equipments

    Energy Technology Data Exchange (ETDEWEB)

    Pilot, Guy [Institut de Radioprotection et de Surete Nucleaire, BP 68, 91192 Gif-sur-Yvette Cedex (France)], E-mail: guy.pilot@irsn.fr; Fauvel, Sylvain [Institut de Radioprotection et de Surete Nucleaire, BP 68, 91192 Gif-sur-Yvette Cedex (France); Gosse, Xavier [AREVA NC, Centre de Marcoule, 30200 Bagnols-sur-Ceze Cedex (France); Dinechin, Guillaume de [Commissariat a l' Energie Atomique, DEN/DM2S/SEMT, Saclay, Bat. 611, 91191 Gif-sur-Yvette Cedex (France); Vernhet, Didier [Commissariat a l' Energie Atomique, DEN/VRH/UMODD, Centre de Valrho, BP 17171, 20207 Bagnols-sur-Ceze Cedex (France)

    2008-08-15

    In order to dismantle some equipments of an obsolete reprocessing plant in Marcoule, studies were carried out by IRSN (Institut de Radioprotection et de Surete Nucleaire)/DSU/SERAC in cooperation with CEA (power laser group) on the laser cutting of steel structures, on the request of AREVA NC/Marcoule (UP1 dismantling project manager) and CEA/UMODD (UP1 dismantling owner). These studies were aimed at: {center_dot}quantifying and characterizing the secondary emissions produced by Nd-YAG laser cutting of Uranus 65 steel pieces and examining the influence of different parameters, {center_dot}qualifying a prefiltration technique and particularly an electrostatic precipitator, {center_dot}comparing the Nd-YAG laser used with other cutting tools previously studied especially on aerosol production and aerosol size distribution.

  9. A Novel Routing Algorithm for Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Raúl Aquino Santos

    2008-01-01

    Full Text Available Este trabajo examina la importancia de las redes inalámbricas ad hoc y el algoritmo de enrutamiento con inundación basada en grupos (LORA-CBF para la comunicación inter-vehicular con la finalidad de optimizar el flujo de tráfico e incrementar la seguridad en las autopistas. Se discute el algoritmo de enrutamiento LORA-CBF y se presentan los resultados de simulaciones realizadas en OPNET de una autopista con alta movilidad vehicular. Primero, el modelo de simulación propuesto se valida a pequeña escala con resultados experimentales. Posteriormente, se emplean simulaciones de nuestro modelo comparándolos con Ad Hoc On-Demand Distance Vector (AODV y Dynamic Source Routing (DSR. Finalmente, se emplea un modelo de tráfico microscópico desarrollado en OPNET para simular la movilidad de 250 vehículos en una autopista y se aplica el algoritmo de enrutamiento LORA-CBF en un escenario vehicular.

  10. Traffic Congestion Detection and Avoidance using Vehicular Communication

    Directory of Open Access Journals (Sweden)

    Ajay Narendrabhai Upadhyaya

    2015-01-01

    Full Text Available Traffic congestion is a serious problem in big cities. With the number of vehicles increasing rapidly, especially in cities whose economy is booming, the situation is getting even worse. Drivers, unaware of congestion ahead eventually join it and increase the severity of it. The ability of a driver to know the traffic conditions on the roads ahead enables him/her to seek alternate routes through which time and fuel can be saved. Due to recent advancements in vehicular technologies, vehicular communication has emerged. The objective of this work is to check feasibility of using infrastructure based vehicular communication for detecting and avoiding traffic congestion. In this paper we propose a Signal Agent (SA and Car Agent(CAbased approach for detecting and avoiding traffic congestion. We analyze performance of the proposed approach for two different road network scenarios using simulations: structured grid network (like Gandhinagar City of Gujarat, India and apart of typical city road network ( Tiwan city. With the proposed approach we get reduction of 10.05% in trip duration of vehicles, reduction of 10.08% in number of vehicles in entire traffic road network and 9.82% in heavy traffic area. In an accident scenario, about 72.63% vehicles changed their route due to awareness of congestion. Error in trip time estimation and vehicle count estimation is observed to be less than 1%.

  11. Correction of Measured Taxicab Exhaust Emission Data Based on Cmem Modle

    Science.gov (United States)

    Li, Q.; Jia, T.

    2017-09-01

    Carbon dioxide emissions from urban road traffic mainly come from automobile exhaust. However, the carbon dioxide emissions obtained by the instruments are unreliable due to time delay error. In order to improve the reliability of data, we propose a method to correct the measured vehicles' carbon dioxide emissions from instrument based on the CMEM model. Firstly, the synthetic time series of carbon dioxide emissions are simulated by CMEM model and GPS velocity data. Then, taking the simulation data as the control group, the time delay error of the measured carbon dioxide emissions can be estimated by the asynchronous correlation analysis, and the outliers can be automatically identified and corrected using the principle of DTW algorithm. Taking the taxi trajectory data of Wuhan as an example, the results show that (1) the correlation coefficient between the measured data and the control group data can be improved from 0.52 to 0.59 by mitigating the systematic time delay error. Furthermore, by adjusting the outliers which account for 4.73 % of the total data, the correlation coefficient can raise to 0.63, which suggests strong correlation. The construction of low carbon traffic has become the focus of the local government. In order to respond to the slogan of energy saving and emission reduction, the distribution of carbon emissions from motor vehicle exhaust emission was studied. So our corrected data can be used to make further air quality analysis.

  12. MEASUREMENT OF AMMONIA EMISSIONS FROM MECHANICALLY VENTILATED POULTRY HOUSES USING MULTIPATH TUNABLE DIODE LASER SPECTROSCOPY

    Science.gov (United States)

    Ammonia emissions from mechanically ventilated poultry operations are an important environmental concern. Open Path Tunable Diode Laser Absorption Spectroscopy has emerged as a robust real-time method for gas phase measurement of ammonia concentrations in agricultural settings. ...

  13. EPA’s Hg Gas Traceability Approach for Source Emissions Measurement and Monitoring

    Science.gov (United States)

    Solicited presentation (special topic) at the International Conference on Mercury as a Global Pollutant on how EPA establishes the NIST traceability of reference materials used to support regulatory mercury emissions measurements.

  14. Locomotive emissions test stand with particulate matter measurement integration : final report.

    Science.gov (United States)

    2015-10-01

    This project builds upon previous research efforts, in which a complete instruction manual and bill of materials was developed for : a blueprint that allows any organization in the railroad industry to build their own locomotive emissions measurement...

  15. Diagnostics of the Solar Wind and Global Heliosphere with Lyman-α Emission Measurements

    Science.gov (United States)

    Provornikova, E. P.; Izmodenov, V. V.; Laming, J. M.; Strachan, L.; Wood, B. E.; Katushkina, O. A.; Ko, Y.-K.; Tun Beltran, S.; Chakrabarti, S.

    2018-02-01

    We propose to develop an instrument measuring full sky intensity maps and spectra of interplanetary Lyman-α emission to reveal the global solar wind variability and the nature of the heliosphere and the local interstellar medium.

  16. A comparison of emission calculations using different modeled indicators with 1-year online measurements.

    Science.gov (United States)

    Lengers, Bernd; Schiefler, Inga; Büscher, Wolfgang

    2013-12-01

    The overall measurement of farm level greenhouse gas (GHG) emissions in dairy production is not feasible, from either an engineering or administrative point of view. Instead, computational model systems are used to generate emission inventories, demanding a validation by measurement data. This paper tests the GHG calculation of the dairy farm-level optimization model DAIRYDYN, including methane (CH₄) from enteric fermentation and managed manure. The model involves four emission calculation procedures (indicators), differing in the aggregation level of relevant input variables. The corresponding emission factors used by the indicators range from default per cow (activity level) emissions up to emission factors based on feed intake, manure amount, and milk production intensity. For validation of the CH₄ accounting of the model, 1-year CH₄ measurements of an experimental free-stall dairy farm in Germany are compared to model simulation results. An advantage of this interdisciplinary study is given by the correspondence of the model parameterization and simulation horizon with the experimental farm's characteristics and measurement period. The results clarify that modeled emission inventories (2,898, 4,637, 4,247, and 3,600 kg CO₂-eq. cow(-1) year(-1)) lead to more or less good approximations of online measurements (average 3,845 kg CO₂-eq. cow(-1) year(-1) (±275 owing to manure management)) depending on the indicator utilized. The more farm-specific characteristics are used by the GHG indicator; the lower is the bias of the modeled emissions. Results underline that an accurate emission calculation procedure should capture differences in energy intake, owing to milk production intensity as well as manure storage time. Despite the differences between indicator estimates, the deviation of modeled GHGs using detailed indicators in DAIRYDYN from on-farm measurements is relatively low (between -6.4% and 10.5%), compared with findings from the literature.

  17. Measurement of liquid radioactive materials for monitoring radioactive emissions

    International Nuclear Information System (INIS)

    1977-10-01

    This draft regulation applies to measuring equipment for liquid radioactive materials for the monitoring of the radioactive discharges from stationary nuclear power plants with LWR and HTR reactors. Demands made on the measuring procedure, methods of concentration determination, balancing, indication of limiting values, and inspections are layed down. The draft regulation deals with: 1) Monitoring liquid radioactive discharges: Water and similar systems; radionuclides and their detection limits, radioactively contaminated water (waste water); secondary cooling water; power house cooling water; primary cooling water; flooding water; 2) Layout of the measuring and sampling equipment and demands made on continuous and discontinuous measuring equipment; demands made on discontinuous α and β measuring equipment; 3) Maintenance and repair work; inspections; repair of defects; 4) Demands made on documentation; reports to authorities; 5) Supplement: List of general and reference regulations. (orig./HP) [de

  18. Measurement of multilayer mirror reflectivity and stimulated emission in the XUV spectral region

    International Nuclear Information System (INIS)

    Keane, C.; Nam, C.H.; Meixler, L.; Milchberg, H.; Skinner, C.H.; Suckewer, S.; Voorhees, D.; Barbee, T.

    1986-03-01

    We present measurements of multilayer mirror reflectivity and stimulated emission in the XUV spectral region. A molybdenum-silicon multilayer mirror with 12% measured reflectivity at 182 A was found to produce a 120% enhancement of the C VI 182 A line (3 → 2 transition) in a strongly recombining plasma. No such enhancement of the CV 186.7 A line was seen, demonstrating amplification of stimulated emission at 182 A

  19. Dismantling of Evaporators by Laser Cutting Measurement of Secondary Emissions

    International Nuclear Information System (INIS)

    Pilot, Guy; Fauvel, Sylvain; Gosse, Xavier; De Dinechin, Guillaume

    2006-01-01

    In order to dismantle the evaporators of an obsolete reprocessing plant in Marcoule, studies were carried out by IRSN (Institut de Radioprotection et de Surete Nucleaire) / DSU/SERAC in cooperation with CEA (power laser group) on the laser cutting of steel structures, on the request of COGEMA (now AREVA NC) /Marcoule (UP1 dismantling project manager) and CEA/UMODD (UP1 dismantling owner). The aim of these studies was: - to quantify and to characterize the secondary emissions produced by Nd-YAG laser cutting of Uranus 65 steel pieces representative of UP1 evaporator elements and to examine the influence of different parameters, - to qualify a pre-filtration technique and particularly an electrostatic precipitator, - to compare the Nd-YAG used with other cutting tools previously studied. The experiments, which took place in a 35 m 3 ventilated cutting cell, allow to underline the following points: for the Uranus 65 steel, the sedimented dross, the deposits on the walls of the cutting cell and the aerosols drawn in the ventilation exhaust duct (∼ 275 m 3 /h), represent respectively between 92% and 99%, between 0.01% and 0.25% and between 1% and 8% of the total collected mass, the attached slag varies much from one configuration to the other and can sometimes amount to a relatively important fraction of the total mass, the kerves vary from 2 mm up to 7 mm for the Uranus 65 steel plates (thickness: 13.8 mm for the single plate and 12.8 + 3.5 mm for the double plate), the exhausted aerosol mass per cut length (g/m) decreases with the cutting speed, varies neither with the stand-off nor with the gas pressure, is dependent upon the gas nature (for the double plate), increases with the laser power, is strongly affected by the nature of the steel (stainless steel or mild steel) and is independent upon the plate position, the size distribution of aerosols is multimodal with a main mode often around 0.45 μm, the electrostatic precipitator has been a satisfactory prefilter

  20. SphinX MEASUREMENTS OF THE 2009 SOLAR MINIMUM X-RAY EMISSION

    OpenAIRE

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Kuzin, S.; Farnik, F.; Reale, F.; Phillips, K. J. H.; Bakala, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B.

    2012-01-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 x 10^47 cm^-3 and 1.1 x 10^48 cm^-3. Comparing Sph...

  1. Measurements of laser generated soft X-ray emission from irradiated gold foils

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J. S.; Keiter, P. A.; Klein, S. R.; Drake, R. P.; Shvarts, D. [University of Michigan, 2455 Hayward St., Ann Arbor, Michigan 48109 (United States); Frank, Y.; Raicher, E.; Fraenkel, M. [Soreq Nuclear Research Center, Yavne (Israel)

    2016-11-15

    Soft x-ray emission from laser irradiated gold foils was measured at the Omega-60 laser system using the Dante photodiode array. The foils were heated with 2 kJ, 6 ns laser pulses and foil thicknesses were varied between 0.5, 1.0, and 2.0 μm. Initial Dante analysis indicates peak emission temperatures of roughly 100 eV and 80 eV for the 0.5 μm and 1.0 μm thick foils, respectively, with little measurable emission from the 2.0 μm foils.

  2. Transient emission and fuel consumption measurements on plant oil tractors

    Directory of Open Access Journals (Sweden)

    Johannes Ettl

    2016-03-01

    Full Text Available Die Bewertung der Umweltwirkung landwirtschaftlicher Fahrzeuge erfordert realitätsnahe Testmethoden zur Erhebung von Abgasemissionen. Am Motorenprüfstand sind dynamische Drehzahl- und Drehmomentzyklen Stand der Technik. Im Traktor eingebaute Motoren wurden überwiegend stationär bei gleichbleibender Drehzahl und Last mithilfe einer Zapfwellenbremse geprüft. Mit einem auf Basis des NRTC (nonroad transient cycle adaptierten Messzyklus lassen sich reproduzierbare, transiente Emissions- und Verbrauchsmessungen an Traktoren durchführen. Die Mittelung der Drehzahl- und Drehmomentvorgaben in 10-Sekunden-Interval­len (10-s-NRTC ermöglicht trotz unvermeidbarer Trägheitsmomente am Traktorenprüfstand die Durchführung eines dynamischen Messzyklus, auch unter Einbeziehung des Kaltstarts. Neben Emissionen und Verbrauch können auch Abgasnachbehandlungssysteme und das Thermomanagement des Gesamtsystems Traktor untersucht und optimiert werden. Bei einer Versuchsreihe konnte das Mittelungsintervall auf bis zu 3 s verkürzt werden und damit die Dynamik dem originalen NRTC-Zyklus gut angenähert werden. Dabei waren die NOX-Emissio­nen lediglich im 3-s-NRTC signifikant höher als im 10-s-NRTC und NRSC. Im angepassten 10-s-NRTC zeigen sich mit Rapsöl geringere Partikelmasse- und höhere HC- und CO-Emissio­nen sowie ein höherer spezifischer Kraftstoffverbrauch im Vergleich zum stationären NRSC (nonroad steady cycle.

  3. Time interval measurement between to emission: a systematics; Mesure de l`intervalle de temps entre deux emissions: une systematique

    Energy Technology Data Exchange (ETDEWEB)

    Bizard, G.; Bougault, R.; Brou, R.; Colin, J.; Durand, D.; Genoux-Lubain, A.; Horn, D.; Kerambrun, A.; Laville, J.L.; Le Brun, C.; Lecolley, J.F.; Lopez, O.; Louvel, M.; Mahi, M.; Meslin, C.; Steckmeyer, J.C.; Tamain, B.; Wieloch, A. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France); LPC (Caen) - CRN (Strasbourg) Collaboration

    1998-04-01

    A systematic study of the evolution of intervals of fragment emission times as a function of the energy deposited in the compound system was performed. Several measurements, Ne at 60 MeV/u, Ar at 30 and 60 MeV/u and two measurements for Kr at 60 MeV/u (central and semi-peripheral collisions) are presented. In all the experiments the target was Au and the mass of the compounds system was around A = 200. The excitation energies per nucleon reached in the case of these heavy systems cover the range of 3 to 5.5 MeV/u. The method used to determine the emission time intervals is based on the correlation functions associated to the relative angle distributions. The gaps between the data and simulations allow to evaluate the emission times. A rapid decrease of these time intervals was observed when the excitation energy increased. This variation starts at 500 fm/c which corresponds to a sequential emission. This relatively long time which indicates a weak interaction between fragments, corresponds practically to the measurement threshold. The shortest intervals (about 50 fm/c) are associated to a spontaneous multifragmentation and were observed in the case of central collisions at Ar+Au and Kr+Au at 60 MeV/u. Two interpretations are possible. The multifragmentation process might be viewed as a sequential process of very short time-separation or else, one can separate two zones heaving in mind that the multifragmentation is predominant from 4,5 MeV/u excitation energy upwards. This question is still open and its study is under way at LPC. An answer could come from the study of the rupture process of an excited nucleus, notably by the determination of its life-time

  4. [Multispectral Radiation Algorithm Based on Emissivity Model Constraints for True Temperature Measurement].

    Science.gov (United States)

    Liang, Mei; Sun, Xiao-gang; Luan, Mei-sheng

    2015-10-01

    Temperature measurement is one of the important factors for ensuring product quality, reducing production cost and ensuring experiment safety in industrial manufacture and scientific experiment. Radiation thermometry is the main method for non-contact temperature measurement. The second measurement (SM) method is one of the common methods in the multispectral radiation thermometry. However, the SM method cannot be applied to on-line data processing. To solve the problems, a rapid inversion method for multispectral radiation true temperature measurement is proposed and constraint conditions of emissivity model are introduced based on the multispectral brightness temperature model. For non-blackbody, it can be drawn that emissivity is an increasing function in the interval if the brightness temperature is an increasing function or a constant function in a range and emissivity satisfies an inequality of emissivity and wavelength in that interval if the brightness temperature is a decreasing function in a range, according to the relationship of brightness temperatures at different wavelengths. The construction of emissivity assumption values is reduced from multiclass to one class and avoiding the unnecessary emissivity construction with emissivity model constraint conditions on the basis of brightness temperature information. Simulation experiments and comparisons for two different temperature points are carried out based on five measured targets with five representative variation trends of real emissivity. decreasing monotonically, increasing monotonically, first decreasing with wavelength and then increasing, first increasing and then decreasing and fluctuating with wavelength randomly. The simulation results show that compared with the SM method, for the same target under the same initial temperature and emissivity search range, the processing speed of the proposed algorithm is increased by 19.16%-43.45% with the same precision and the same calculation results.

  5. In Situ Measurement of Alkali Metals in an MSW Incinerator Using a Spontaneous Emission Spectrum

    Directory of Open Access Journals (Sweden)

    Weijie Yan

    2017-03-01

    Full Text Available This paper presents experimental investigations of the in situ diagnosis of the alkali metals in the municipal solid waste (MSW flame of an industrial grade incinerator using flame emission spectroscopy. The spectral radiation intensities of the MSW flame were obtained using a spectrometer. A linear polynomial fitting method is proposed to uncouple the continuous spectrum and the characteristic line. Based on spectra processing and a non-gray emissivity model, the flame temperature, emissivity, and intensities of the emission of alkali metals were calculated by means of measuring the spectral radiation intensities of the MSW flame. Experimental results indicate that the MSW flame contains alkali metals, including Na, K, and even Rb, and it demonstrates non-gray characteristics in a wavelength range from 500 nm to 900 nm. Peak intensities of the emission of the alkali metals were found to increase when the primary air was high, and the measured temperature varied in the same way as the primary air. The temperature and peak intensities of the lines of emission of the alkali metals may be used to adjust the primary airflow and to manage the feeding of the MSW to control the alkali metals in the MSW flame. It was found that the peak intensity of the K emission line had a linear relationship with the peak intensity of the Na emission line; this correlation may be attributed to their similar physicochemical characteristics in the MSW. The variation trend of the emissivity of the MSW flame and the oxygen content in the flue gas were almost opposite because the increased oxygen content suppressed soot formation and decreased soot emissivity. These results prove that the flame emission spectroscopy technique is feasible for monitoring combustion in the MSW incinerator in situ.

  6. An assessment of the real-world driving gaseous emissions from a Euro 6 light-duty diesel vehicle using a portable emissions measurement system (PEMS)

    Science.gov (United States)

    Luján, José M.; Bermúdez, Vicente; Dolz, Vicente; Monsalve-Serrano, Javier

    2018-02-01

    Recent investigations demonstrated that real-world emissions usually exceed the levels achieved in the laboratory based type approval processes. By means of on-board emissions measurements, it has been shown that nitrogen oxides emitted by diesel engines substantially exceed the limit imposed by the Euro 6 regulation. Thus, with the aim of complementing the worldwide harmonized light vehicles test cycle, the real driving emissions cycle will be introduced after 1 September 2017 to regulate the vehicle emissions in real-world driving situations. This paper presents on-board gaseous emissions measurements from a Euro 6 light-duty diesel vehicle in a real-world driving route using a portable emissions measurement system. The test route characteristics follow the requirements imposed by the RDE regulation. The analysis of the raw emissions results suggests that the greatest amount of nitrogen oxides and nitrogen dioxide are emitted during the urban section of the test route, confirming that lower speeds with more accelerations and decelerations lead to higher nitrogen oxides emissions levels than constant high speeds. Moreover, the comparison of the two calculation methods proposed by the real driving emissions regulation has revealed emissions rates differences ranging from 10% to 45% depending on the pollutant emission and the trip section considered (urban or total). Thus, the nitrogen oxides emissions conformity factor slightly varies from one method to the other.

  7. On the time-averaging of ultrafine particle number size spectra in vehicular plumes

    Directory of Open Access Journals (Sweden)

    X. H. Yao

    2006-01-01

    Full Text Available Ultrafine vehicular particle (<100 nm number size distributions presented in the literature are mostly averages of long scan-time (~30 s or more spectra mainly due to the non-availability of commercial instruments that can measure particle distributions in the <10 nm to 100 nm range faster than 30 s even though individual researchers have built faster (1–2.5 s scanning instruments. With the introduction of the Engine Exhaust Particle Sizer (EEPS in 2004, high time-resolution (1 full 32-channel spectrum per second particle size distribution data become possible and allow atmospheric researchers to study the characteristics of ultrafine vehicular particles in rapidly and perhaps randomly varying high concentration environments such as roadside, on-road and tunnel. In this study, particle size distributions in these environments were found to vary as rapidly as one second frequently. This poses the question on the generality of using averages of long scan-time spectra for dynamic and/or mechanistic studies in rapidly and perhaps randomly varying high concentration environments. One-second EEPS data taken at roadside, on roads and in tunnels by a mobile platform are time-averaged to yield 5, 10, 30 and 120 s distributions to answer this question.

  8. Measurements of the low-energy gamma-ray continuum emission from the Galactic Center direction

    International Nuclear Information System (INIS)

    Jardim, M.V.A.; Martin, I.M.; Jardim, J.O.D.

    1982-07-01

    The measurement of the gamma-ray continuum emission from the Galactic Center (GC) can provide us information about the physical processes taking place there at the site of emission. Using the data obtained with a balloon-borne gamma-ray telescope to measure gamma-rays in the energy interval between 0,3 and 3 MeV, which was launched on March 28, 1980 from Cachoeira Paulista (SP), we calculeted two points for the continuum spectrum in the range between 0,34 and 0,67 MeV. The points are related to the GC emission radiated in the longitude interval - 31 0 0 . The measurements are compatible with the observations in 1969 and 1972 by Haymes et alii and Johnson, respectively. The power law spectrum suggests that the main component for the gamma-ray continuum emission below 10 MeV is dominated by the bremsstrahlung due to relativistic electrons. (Author) [pt

  9. Continuous Emission Spectrum Measurement for Electron Temperature Determination in Low-Temperature Collisional Plasmas

    International Nuclear Information System (INIS)

    Liu Qiuyan; Li Hong; Chen Zhipeng; Xie Jinlin; Liu Wandong

    2011-01-01

    Continuous emission spectrum measurement is applied for the inconvenient diagnostics of low-temperature collisional plasmas. According to the physical mechanism of continuous emission, a simplified model is presented to analyze the spectrum in low temperature plasma. The validity of this model is discussed in a wide range of discharge parameters, including electron temperature and ionization degree. Through the simplified model, the continuous emission spectrum in a collisional argon internal inductively coupled plasma is experimentally measured to determine the electron temperature distribution for different gas pressures and radio-frequency powers. The inverse Abel transform is also applied for a better spatially resoluted results. Meanwhile, the result of the continuous emission spectrum measurement is compared to that of the electrostatic double probes, which indicates the effectiveness of this method. (low temperature plasma)

  10. A Study on Vehicle Emission Factor Correction Based on Fuel Consumption Measurement

    Science.gov (United States)

    Wang, Xiaoning; Li, Meng; Peng, Bo

    2018-01-01

    The objective of this study is to address the problem of obvious differences between the calculated and measured emissions of pollutants from motor vehicle by using the existing "Environmental Impact Assessment Specification of Highway Construction Projects". First, a field study collects the vehicle composition ratio, speed, slope, fuel consumption and other essential data. Considering practical applications, the emission factors corresponding to 40km/h and 110km/h and 120km/h velocity are introduced by data fitting. Then, the emission factors of motor vehicle are revised based on the measured fuel consumption, and the pollutant emission modified formula was calculated and compared with the standard recommendation formula. The results show the error between calculated and measured values are within 5%, which can better reflect the actual discharge of the motor vehicle.

  11. Deriving fuel-based emission factor thresholds to interpret heavy-duty vehicle roadside plume measurements.

    Science.gov (United States)

    Quiros, David C; Smith, Jeremy D; Ham, Walter A; Robertson, William H; Huai, Tao; Ayala, Alberto; Hu, Shaohua

    2018-04-13

    Remote sensing devices have been used for decades to measure gaseous emissions from individual vehicles at the roadside. Systems have also been developed that entrain diluted exhaust and can also measure particulate matter (PM) emissions. In 2015, the California Air Resources Board (CARB) reported that 8% of in-field diesel particulate filters (DPF) on heavy-duty (HD) vehicles were malfunctioning and emitted about 70% of total diesel PM emissions from the DPF-equipped fleet. A new high-emitter problem in the heavy-duty vehicle fleet had emerged. Roadside exhaust plume measurements reflect a snapshot of real-world operation, typically lasting several seconds. In order to relate roadside plume measurements to laboratory emission tests, we analyzed carbon dioxide (CO 2 ), oxides of nitrogen (NO X ), and PM emissions collected from four HD vehicles during several driving cycles on a chassis dynamometer. We examined the fuel-based emission factors corresponding to possible exceedances of emission standards as a function of vehicle power. Our analysis suggests that a typical HD vehicle will exceed the model year (MY) 2010 emission standards (of 0.2 g NO X /bhp-hr and 0.01 g PM/bhp-hr) by three times when fuel-based emission factors are 9.3 g NO X /kg fuel and 0.11 g PM/kg using the roadside plume measurement approach. Reported limits correspond to 99% confidence levels, which were calculated using the detection uncertainty of emissions analyzers, accuracy of vehicle power calculations, and actual emissions variability of fixed operational parameters. The PM threshold was determined for acceleration events between 0.47 and 1.4 mph/sec only, and the NO X threshold was derived from measurements where aftertreatment temperature was above 200°C. Anticipating a growing interest in real-world driving emissions, widespread implementation of roadside exhaust plume measurements as a compliment to in-use vehicle programs may benefit from expanding this analysis to a larger

  12. VISIONS Vehicular communication Improvement : solution based on IMS Operational Nodes and Services

    OpenAIRE

    Lequerica Roca, Iván

    2013-01-01

    Digital services and communications in vehicular scenarios provide the essential assets to improve road transport in several ways like reducing accidents, improving traffic efficiency and optimizing the transport of goods and people. Vehicular communications typically rely on VANET (Vehicular Ad hoc Networks). In these networks vehicles communicate with each other without the need of infrastructure. VANET are mainly oriented to disseminate information to the vehicles in certain geographic are...

  13. Short paper: Distributed vehicular traffic congestion detection algorithm for urban environments

    OpenAIRE

    Milojevic, M.; Rakocevic, V.

    2013-01-01

    Vehicular traffic congestion is a well-known economic and social problem generating significant costs and safety challenges, and increasing pollution in the cities. Current intelligent transport systems and vehicular networking technologies rely heavily on the supporting network infrastructure which is still not widely available. This paper contributes towards the development of distributed and cooperative vehicular traffic congestion detection by proposing a new vehicle-to-vehicle (V2V) cong...

  14. Programs and measures to reduce GHG emissions in agriculture and waste treatment in Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    Mareckova, K.; Bratislava, S.; Kucirek, S.

    1996-12-31

    Slovakia is a UN FCCC Annex I country and is obliged to limit its anthropogenic GHG emissions in the year 2000 to 1990 level. The key greenhouse gas in Slovakia is CO{sub 2} resulting mainly from fuel combustion processes. However the share of CH{sub 4} and N{sub 2}O is approximately 20% of the total emissions on GWP basis. These gases are occurring mainly in non-energy sectors. The construction of the non-CO{sub 2} emission scenarios to reduce GHG and the uncertainty in N{sub 2}O and CH{sub 4} emission estimation are discussed focusing on agriculture and waste treatment. The presentation will also include information on emission trends of CH{sub 4} and N{sub 2}O since 1988. There are already implemented measures reducing GHG emissions in Slovakia, however, not motivated by global warming. A short view of implemented measures with an assessment of their benefit concerning non-CO{sub 2} GHG emissions reduction and some proposed mitigation options for agriculture and waste treatment are shown. Expected difficulties connected with preparing scenarios and with implementation of reducing measures are discussed.

  15. Direct measurements show decreasing methane emissions from natural gas local distribution systems in the United States.

    Science.gov (United States)

    Lamb, Brian K; Edburg, Steven L; Ferrara, Thomas W; Howard, Touché; Harrison, Matthew R; Kolb, Charles E; Townsend-Small, Amy; Dyck, Wesley; Possolo, Antonio; Whetstone, James R

    2015-04-21

    Fugitive losses from natural gas distribution systems are a significant source of anthropogenic methane. Here, we report on a national sampling program to measure methane emissions from 13 urban distribution systems across the U.S. Emission factors were derived from direct measurements at 230 underground pipeline leaks and 229 metering and regulating facilities using stratified random sampling. When these new emission factors are combined with estimates for customer meters, maintenance, and upsets, and current pipeline miles and numbers of facilities, the total estimate is 393 Gg/yr with a 95% upper confidence limit of 854 Gg/yr (0.10% to 0.22% of the methane delivered nationwide). This fraction includes emissions from city gates to the customer meter, but does not include other urban sources or those downstream of customer meters. The upper confidence limit accounts for the skewed distribution of measurements, where a few large emitters accounted for most of the emissions. This emission estimate is 36% to 70% less than the 2011 EPA inventory, (based largely on 1990s emission data), and reflects significant upgrades at metering and regulating stations, improvements in leak detection and maintenance activities, as well as potential effects from differences in methodologies between the two studies.

  16. Industrial point source CO2 emission strength estimation with aircraft measurements and dispersion modelling.

    Science.gov (United States)

    Carotenuto, Federico; Gualtieri, Giovanni; Miglietta, Franco; Riccio, Angelo; Toscano, Piero; Wohlfahrt, Georg; Gioli, Beniamino

    2018-02-22

    CO 2 remains the greenhouse gas that contributes most to anthropogenic global warming, and the evaluation of its emissions is of major interest to both research and regulatory purposes. Emission inventories generally provide quite reliable estimates of CO 2 emissions. However, because of intrinsic uncertainties associated with these estimates, it is of great importance to validate emission inventories against independent estimates. This paper describes an integrated approach combining aircraft measurements and a puff dispersion modelling framework by considering a CO 2 industrial point source, located in Biganos, France. CO 2 density measurements were obtained by applying the mass balance method, while CO 2 emission estimates were derived by implementing the CALMET/CALPUFF model chain. For the latter, three meteorological initializations were used: (i) WRF-modelled outputs initialized by ECMWF reanalyses; (ii) WRF-modelled outputs initialized by CFSR reanalyses and (iii) local in situ observations. Governmental inventorial data were used as reference for all applications. The strengths and weaknesses of the different approaches and how they affect emission estimation uncertainty were investigated. The mass balance based on aircraft measurements was quite succesful in capturing the point source emission strength (at worst with a 16% bias), while the accuracy of the dispersion modelling, markedly when using ECMWF initialization through the WRF model, was only slightly lower (estimation with an 18% bias). The analysis will help in highlighting some methodological best practices that can be used as guidelines for future experiments.

  17. Particle and VOC emission factor measurements for anthropogenic sources in West Africa

    Directory of Open Access Journals (Sweden)

    S. Keita

    2018-06-01

    Full Text Available A number of campaigns have been carried out to establish the emission factors of pollutants from fuel combustion in West Africa, as part of work package 2 (Air Pollution and Health of the DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa FP7 program. Emission sources considered here include wood (hevea and iroko and charcoal burning, charcoal making, open trash burning, and vehicle emissions, including trucks, cars, buses and two-wheeled vehicles. Emission factors of total particulate matter (TPM, elemental carbon (EC, primary organic carbon (OC and volatile organic compounds (VOCs have been established. In addition, emission factor measurements were performed in combustion chambers in order to reproduce field burning conditions for a tropical hardwood (hevea, and obtain particulate emission factors by size (PM0.25, PM1, PM2.5 and PM10. Particle samples were collected on quartz fiber filters and analyzed using gravimetric method for TPM and thermal methods for EC and OC. The emission factors of 58 VOC species were determined using offline sampling on a sorbent tube. Emission factor results for two species of tropical hardwood burning of EC, OC and TPM are 0.98 ± 0.46 g kg−1 of fuel burned (g kg−1, 11.05 ± 4.55 and 41.12 ± 24.62 g kg−1, respectively. For traffic sources, the highest emission factors among particulate species are found for the two-wheeled vehicles with two-stroke engines (2.74 g kg−1 fuel for EC, 65.11 g kg−1 fuel for OC and 496 g kg−1 fuel for TPM. The largest VOC emissions are observed for two-stroke two-wheeled vehicles, which are up to 3 times higher than emissions from light-duty and heavy-duty vehicles. Isoprene and monoterpenes, which are usually associated with biogenic emissions, are present in almost all anthropogenic sources investigated during this work and could be as significant as aromatic emissions in wood burning (1 g kg−1 fuel. EC is

  18. 124Sb - Activity measurement and determination of photon emission intensities

    International Nuclear Information System (INIS)

    Be, M.M.; Chauvenet, B.

    2009-07-01

    The international traceability of antimony 124, in term of activity, is very limited. The results of 124 Sb activity measurements sent to the SIR (BIPM - International System of Reference, BIPM.RI(II)-K1.Sb-124.) are scarce. Up to now, only three laboratories have contributed. Two of them carried out measurements using the 4πβ-γ coincidence counting technique and the third one using the 4πγ method with a well-type crystal detector. The first two results are in agreement but the last one differs significantly from them, by 2 %. The decay scheme consistency cannot be excluded when trying to explain those discrepancies. In other respects, this nuclide emits high-energy gamma rays, and then could be selected as a valuable standard radionuclide for the calibration of gamma-ray detectors in that energy range, given well known photon intensities. Those considerations led to the proposal of an international exercise and to the realisation of this Euromet project, registered as project no. 907, coordinated by CEA-List-LNE/LNHB. The first part of this exercise was dedicated to activity measurements and to their comparison. For this purpose, participants were asked to make use of all the direct measurement techniques available in their laboratory in order to confirm or not the existence of possible biases specific to some measuring methods. In addition, this exercise offered the opportunity of improving the uncertainties of the gamma-ray intensities. Then, participants were asked, in the second part of the exercise, to carry out X-ray and gamma-ray intensity measurements. These results have been compared to previous published values and new decay scheme data are proposed. Eight international laboratories participated in this exercise. (authors)

  19. In situ emission measurements in the wake of subsonic jet airliners at cruise altitude

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, P; Schlager, H; Schumann, U [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere; Baughcum, St [Boeing Co., Seattle, WA (United States); Deidewig, F [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Antriebstechnik

    1998-12-31

    In the course of the POLINAT campaigns of 1994 and 1995 several flights were carried out to measure NO{sub x} and CO{sub 2} in the young exhaust plumes of commercial wide-bodied jet airlines at altitude. From these measurements in flight NO{sub x} emission indices were derived which were used to test current NO{sub x} emission index prediction methods. Taking into account the error of the measurements and uncertainties in the input parameters for the predictions, the results of the two fuel flow base prediction methods agreed well with the measured values. (author) 13 refs.

  20. Measurement of electron emission due to energetic ion bombardment in plasma source ion implantation

    Science.gov (United States)

    Shamim, M. M.; Scheuer, J. T.; Fetherston, R. P.; Conrad, J. R.

    1991-11-01

    An experimental procedure has been developed to measure electron emission due to energetic ion bombardment during plasma source ion implantation. Spherical targets of copper, stainless steel, graphite, titanium alloy, and aluminum alloy were biased negatively to 20, 30, and 40 kV in argon and nitrogen plasmas. A Langmuir probe was used to detect the propagating sheath edge and a Rogowski transformer was used to measure the current to the target. The measurements of electron emission coefficients compare well with those measured under similar conditions.

  1. In situ emission measurements in the wake of subsonic jet airliners at cruise altitude

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, P.; Schlager, H.; Schumann, U. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere; Baughcum, St. [Boeing Co., Seattle, WA (United States); Deidewig, F. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Antriebstechnik

    1997-12-31

    In the course of the POLINAT campaigns of 1994 and 1995 several flights were carried out to measure NO{sub x} and CO{sub 2} in the young exhaust plumes of commercial wide-bodied jet airlines at altitude. From these measurements in flight NO{sub x} emission indices were derived which were used to test current NO{sub x} emission index prediction methods. Taking into account the error of the measurements and uncertainties in the input parameters for the predictions, the results of the two fuel flow base prediction methods agreed well with the measured values. (author) 13 refs.

  2. Positron emission medical measurements with accelerated radioactive ion beams

    International Nuclear Information System (INIS)

    Llacer, J.

    1988-01-01

    This paper reviews in some detail the process by which a heavy ion accelerator can be used to inject positron emitting radioactive particles into a human body for a range of possible medical measurements. The process of radioactive beam generation and injection is described, followed by a study of the relationship between activity that can be injected versus dose to the patient as a function of which of the positron emitting ions is used. It is found that 6 C 10 and 10 Ne 19 are the two isotopes that appear more promising for injection into humans. The design considerations for a non-tomographic instrument to obtain images from beam injections are outlined and the results of 10 Ne 19 preliminary measurements with human phantoms and actual patients for the determination of end-of-range of cancer therapy ion beams is reported. Accuracies in the order of ±1 mm in the measurements of stopping point of a therapy beam with safe doses to the patient are reported. The paper concludes with a simple analysis of requirements to extend the technique to on-line verification of cancer treatment and to nuclear medicine research and diagnostics measurements. 17 refs.; 16 figs.; 3 tabs

  3. Development of a low-maintenance measurement approach to continuously estimate methane emissions: A case study.

    Science.gov (United States)

    Riddick, S N; Hancock, B R; Robinson, A D; Connors, S; Davies, S; Allen, G; Pitt, J; Harris, N R P

    2018-03-01

    The chemical breakdown of organic matter in landfills represents a significant source of methane gas (CH 4 ). Current estimates suggest that landfills are responsible for between 3% and 19% of global anthropogenic emissions. The net CH 4 emissions resulting from biogeochemical processes and their modulation by microbes in landfills are poorly constrained by imprecise knowledge of environmental constraints. The uncertainty in absolute CH 4 emissions from landfills is therefore considerable. This study investigates a new method to estimate the temporal variability of CH 4 emissions using meteorological and CH 4 concentration measurements downwind of a landfill site in Suffolk, UK from July to September 2014, taking advantage of the statistics that such a measurement approach offers versus shorter-term, but more complex and instantaneously accurate, flux snapshots. Methane emissions were calculated from CH 4 concentrations measured 700m from the perimeter of the landfill with observed concentrations ranging from background to 46.4ppm. Using an atmospheric dispersion model, we estimate a mean emission flux of 709μgm -2 s -1 over this period, with a maximum value of 6.21mgm -2 s -1 , reflecting the wide natural variability in biogeochemical and other environmental controls on net site emission. The emissions calculated suggest that meteorological conditions have an influence on the magnitude of CH 4 emissions. We also investigate the factors responsible for the large variability observed in the estimated CH 4 emissions, and suggest that the largest component arises from uncertainty in the spatial distribution of CH 4 emissions within the landfill area. The results determined using the low-maintenance approach discussed in this paper suggest that a network of cheaper, less precise CH 4 sensors could be used to measure a continuous CH 4 emission time series from a landfill site, something that is not practical using far-field approaches such as tracer release methods

  4. Plant-integrated measurement of greenhouse gas emissions from a municipal wastewater treatment plant

    DEFF Research Database (Denmark)

    Yoshida, Hiroko; Mønster, Jacob; Scheutz, Charlotte

    2014-01-01

    experiencing operational problems, such as during foaming events in anaerobic digesters and during sub-optimal operation of biological nitrogen removal in the secondary treatment of wastewater. Methane emissions detected during measurement campaigns corresponded to 2.07-32.7% of the methane generated......Wastewater treatment plants (WWTPs) contribute to anthropogenic greenhouse gas (GHG) emissions. Due to its spatial and temporal variation in emissions, whole plant characterization of GHG emissions from WWTPs face a number of obstacles. In this study, a tracer dispersion method was applied...... in the plant. As high as 4.27% of nitrogen entering the WWTP was emitted as nitrous oxide under the sub-optimal operation of biological treatment processes. The study shows that the unit process configuration, as well as the operation of the WWTP, determines the rate of GHG emission. The applied plant...

  5. Contribution to design a communication framework for vehicular ad hoc networks in urban scenarios

    OpenAIRE

    Tripp Barba, Carolina

    2013-01-01

    La movilidad constante de las personas y la creciente necesidad de estar conectados en todo momento ha hecho de las redes vehiculares un área cuyo interés ha ido en aumento. La gran cantidad de vehículos que hay en la actualidad, y los avances tecnológicos han hecho de las redes vehiculares (VANETS, Vehicular Ad hoc Networks) un gran campo de investigación. Las redes vehiculares son un tipo especial de redes móviles ad hoc inalámbricas, las cuales, al igual que las redes MANET (Mobile Ad hoc ...

  6. An Eco-Driving Advisory System for Continuous Signalized Intersections by Vehicular Ad Hoc Network

    Directory of Open Access Journals (Sweden)

    Wei-Hsun Lee

    2018-01-01

    Full Text Available With the vehicular ad hoc network (VANET technology which support vehicle-to-vehicle (V2V and vehicle to road side unit (V2R/R2V communications, vehicles can preview the intersection signal plan such as signal countdown message. In this paper, an ecodriving advisory system (EDAS is proposed to reduce CO2 emissions and energy consumption by letting the vehicle continuously pass through multiple intersections with the minimum possibilities of stops. We extend the isolated intersection model to multiple continuous intersections scenario. A hybrid method combining three strategies including maximized throughput model (MTM, smooth speed model (SSM, and minimized acceleration and deceleration (MinADM is designed, and it is compared with related works maximized throughput model (MaxTM, open traffic light control model (OTLCM, and predictive cruise control (PCC models. Some issues for the practical application including safe car following, queue clearing, and gliding mode are discussed and conquered. Simulation results show that the proposed model outperforms OTLCM 25.1%~81.2% in the isolated intersection scenario for the CO2 emissions and 20.5%~84.3% in averaged travel time. It also performs better than the compared PCC model in CO2 emissions (19.9%~31.2% as well as travel time (24.5%~35.9% in the multiple intersections scenario.

  7. Field test of available methods to measure remotely SOx and NOx emissions from ships

    Science.gov (United States)

    Balzani Lööv, J. M.; Alfoldy, B.; Gast, L. F. L.; Hjorth, J.; Lagler, F.; Mellqvist, J.; Beecken, J.; Berg, N.; Duyzer, J.; Westrate, H.; Swart, D. P. J.; Berkhout, A. J. C.; Jalkanen, J.-P.; Prata, A. J.; van der Hoff, G. R.; Borowiak, A.

    2014-08-01

    Methods for the determination of ship fuel sulphur content and NOx emission factors based on remote measurements have been compared in the harbour of Rotterdam and compared to direct stack emission measurements on the ferry Stena Hollandica. The methods were selected based on a review of the available literature on ship emission measurements. They were either optical (LIDAR, Differential Optical Absorption Spectroscopy (DOAS), UV camera), combined with model-based estimates of fuel consumption, or based on the so called "sniffer" principle, where SO2 or NOx emission factors are determined from simultaneous measurement of the increase of CO2 and SO2 or NOx concentrations in the plume of the ship compared to the background. The measurements were performed from stations at land, from a boat and from a helicopter. Mobile measurement platforms were found to have important advantages compared to the land-based ones because they allow optimizing the sampling conditions and sampling from ships on the open sea. Although optical methods can provide reliable results it was found that at the state of the art level, the "sniffer" approach is the most convenient technique for determining both SO2 and NOx emission factors remotely. The average random error on the determination of SO2 emission factors comparing two identical instrumental set-ups was 6%. However, it was found that apparently minor differences in the instrumental characteristics, such as response time, could cause significant differences between the emission factors determined. Direct stack measurements showed that about 14% of the fuel sulphur content was not emitted as SO2. This was supported by the remote measurements and is in agreement with the results of other field studies.

  8. Field test of available methods to measure remotely SO2 and NOx emissions from ships

    Science.gov (United States)

    Balzani Lööv, J. M.; Alfoldy, B.; Beecken, J.; Berg, N.; Berkhout, A. J. C.; Duyzer, J.; Gast, L. F. L.; Hjorth, J.; Jalkanen, J.-P.; Lagler, F.; Mellqvist, J.; Prata, F.; van der Hoff, G. R.; Westrate, H.; Swart, D. P. J.; Borowiak, A.

    2013-11-01

    Methods for the determination of ship fuel sulphur content and NOx emission factors from remote measurements have been compared in the harbour of Rotterdam and compared to direct stack emission measurements on the ferry Stena Hollandica. The methods were selected based on a review of the available literature on ship emission measurements. They were either optical (LIDAR, DOAS, UV camera), combined with model based estimates of fuel consumption, or based on the so called "sniffer" principle, where SO2 or NOx emission factors are determined from simultaneous measurement of the increase of CO2 and SO2 or NOx concentrations in the plume of the ship compared to the background. The measurements were performed from stations at land, from a boat, and from a helicopter. Mobile measurement platforms were found to have important advantages compared to the landbased ones because they allow to optimize the sampling conditions and to sample from ships on the open sea. Although optical methods can provide reliable results, it was found that at the state of the art, the "sniffer" approach is the most convenient technique for determining both SO2 and NOx emission factors remotely. The average random error on the determination of SO2 emission factors comparing two identical instrumental set-ups was 6%. However, it was found that apparently minor differences in the instrumental characteristics, such as response time, could cause significant differences between the emission factors determined. Direct stack measurements showed that about 14% of the fuel sulphur content was not emitted as SO2. This was supported by the remote measurements and is in agreement with the results of other field studies.

  9. Highly controlled, reproducible measurements of aerosol emissions from combustion of a common African biofuel source

    Science.gov (United States)

    Haslett, Sophie L.; Thomas, J. Chris; Morgan, William T.; Hadden, Rory; Liu, Dantong; Allan, James D.; Williams, Paul I.; Keita, Sekou; Liousse, Cathy; Coe, Hugh

    2018-01-01

    Particulate emissions from biomass burning can both alter the atmosphere's radiative balance and cause significant harm to human health. However, due to the large effect on emissions caused by even small alterations to the way in which a fuel burns, it is difficult to study particulate production of biomass combustion mechanistically and in a repeatable manner. In order to address this gap, in this study, small wood samples sourced from Côte D'Ivoire in West Africa were burned in a highly controlled laboratory environment. The shape and mass of samples, available airflow and surrounding thermal environment were carefully regulated. Organic aerosol and refractory black carbon emissions were measured in real time using an Aerosol Mass Spectrometer and a Single Particle Soot Photometer, respectively. This methodology produced remarkably repeatable results, allowing aerosol emissions to be mapped directly onto different phases of combustion. Emissions from pyrolysis were visible as a distinct phase before flaming was established. After flaming combustion was initiated, a black-carbon-dominant flame was observed during which very little organic aerosol was produced, followed by a period that was dominated by organic-carbon-producing smouldering combustion, despite the presence of residual flaming. During pyrolysis and smouldering, the two phases producing organic aerosol, distinct mass spectral signatures that correspond to previously reported variations in biofuel emissions measured in the atmosphere are found. Organic aerosol emission factors averaged over an entire combustion event were found to be representative of the time spent in the pyrolysis and smouldering phases, rather than reflecting a coupling between emissions and the mass loss of the sample. Further exploration of aerosol yields from similarly carefully controlled fires and a careful comparison with data from macroscopic fires and real-world emissions will help to deliver greater constraints on the

  10. Integral emission factors for methane determined using urban flux measurements and local-scale inverse models

    Science.gov (United States)

    Christen, Andreas; Johnson, Mark; Molodovskaya, Marina; Ketler, Rick; Nesic, Zoran; Crawford, Ben; Giometto, Marco; van der Laan, Mike

    2013-04-01

    The most important long-lived greenhouse gas (LLGHG) emitted during combustion of fuels is carbon dioxide (CO2), however also traces of the LLGHGs methane (CH4) and nitrous oxide (N2O) are released, the quantities of which depend largely on the conditions of the combustion process. Emission factors determine the mass of LLGHGs emitted per energy used (or kilometre driven for cars) and are key inputs for bottom-up emission modelling. Emission factors for CH4 are typically determined in the laboratory or on a test stand for a given combustion system using a small number of samples (vehicles, furnaces), yet associated with larger uncertainties when scaled to entire fleets. We propose an alternative, different approach - Can integrated emission factors be independently determined using direct micrometeorological flux measurements over an urban surface? If so, do emission factors determined from flux measurements (top-down) agree with up-scaled emission factors of relevant combustion systems (heating, vehicles) in the source area of the flux measurement? Direct flux measurements of CH4 were carried out between February and May, 2012 over a relatively densely populated, urban surface in Vancouver, Canada by means of eddy covariance (EC). The EC-system consisted of an ultrasonic anemometer (CSAT-3, Campbell Scientific Inc.) and two open-path infrared gas analyzers (Li7500 and Li7700, Licor Inc.) on a tower at 30m above the surface. The source area of the EC system is characterised by a relative homogeneous morphometry (5.3m average building height), but spatially and temporally varying emission sources, including two major intersecting arterial roads (70.000 cars drive through the 50% source area per day) and seasonal heating in predominantly single-family houses (natural gas). An inverse dispersion model (turbulent source area model), validated against large eddy simulations (LES) of the urban roughness sublayer, allows the determination of the spatial area that

  11. Evaluating BC and NOx emission inventories for the Paris region from MEGAPOLI aircraft measurements

    Science.gov (United States)

    Petetin, H.; Beekmann, M.; Colomb, A.; Denier van der Gon, H. A. C.; Dupont, J.-C.; Honoré, C.; Michoud, V.; Morille, Y.; Perrussel, O.; Schwarzenboeck, A.; Sciare, J.; Wiedensohler, A.; Zhang, Q. J.

    2015-09-01

    High uncertainties affect black carbon (BC) emissions, and, despite its important impact on air pollution and climate, very few BC emissions evaluations are found in the literature. This paper presents a novel approach, based on airborne measurements across the Paris, France, plume, developed in order to evaluate BC and NOx emissions at the scale of a whole agglomeration. The methodology consists in integrating, for each transect, across the plume observed and simulated concentrations above background. This allows for several error sources (e.g., representativeness, chemistry, plume lateral dispersion) to be minimized in the model used. The procedure is applied with the CHIMERE chemistry-transport model to three inventories - the EMEP inventory and the so-called TNO and TNO-MP inventories - over the month of July 2009. Various systematic uncertainty sources both in the model (e.g., boundary layer height, vertical mixing, deposition) and in observations (e.g., BC nature) are discussed and quantified, notably through sensitivity tests. Large uncertainty values are determined in our results, which limits the usefulness of the method to rather strongly erroneous emission inventories. A statistically significant (but moderate) overestimation is obtained for the TNO BC emissions and the EMEP and TNO-MP NOx emissions, as well as for the BC / NOx emission ratio in TNO-MP. The benefit of the airborne approach is discussed through a comparison with the BC / NOx ratio at a ground site in Paris, which additionally suggests a spatially heterogeneous error in BC emissions over the agglomeration.

  12. Differences between emissions measured in urban driving and certification testing of heavy-duty diesel engines

    Science.gov (United States)

    Dixit, Poornima; Miller, J. Wayne; Cocker, David R.; Oshinuga, Adewale; Jiang, Yu; Durbin, Thomas D.; Johnson, Kent C.

    2017-10-01

    Emissions from eight heavy-duty diesel trucks (HDDTs) equipped with three different exhaust aftertreatment systems (ATS) for controlling nitrogen oxide (NOx) emissions were quantified on a chassis dynamometer using driving schedules representative of stop-and-go and free-flow driving in metropolitan areas. The three control technologies were: 1) cooled exhaust gas recirculation (CEGR) plus a diesel particulate filter (DPF); 2) CEGR and DPF plus advanced engine controls; and 3) CEGR and DPF plus selective catalytic reduction with ammonia (SCR). Results for all control technologies and driving conditions showed PM emission factors were less than the standard, while selected non-regulated emissions (ammonia, carbonyls, and C4-C12 hydrocarbons) and a greenhouse gas (nitrous oxide) were at measurement detection limits. However, NOx emission factors depended on the control technology, engine calibration, and driving mode. For example, emissions from engines with cooled-exhaust gas recirculation (CEGR) were 239% higher for stop-and-go driving as compared with free-flow. For CEGR plus selective catalytic reduction (SCR), the ratio was 450%. A deeper analysis was carried out with the assumption that emissions measured for a drive cycle on either the chassis or in-use driving would be similar. Applying the same NTE rules to the chassis data showed emissions during stop-and-go driving often exceeded the certification standard and >90% of the driving did not fall within the Not-To-Exceed (NTE) control area suggesting the NTE requirements do not provide sufficient emissions control under in-use conditions. On-road measurement of emissions using the same mobile lab while the vehicle followed a free-flow driving schedule verified the chassis results. These results have implications for scientists who build inventories using certification values instead of real world emission values and for metropolitan populations, who are exposed to elevated emissions. The differences in values

  13. Final Report: Wireless Instrument for Automated Measurement of Clean Cookstove Usage and Black Carbon Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Lukac, Martin [Cirrus Sense LLC, Los Angeles, CA (United States); Ramanathan, Nithya [Cirrus Sense LLC, Los Angeles, CA (United States); Graham, Eric [Cirrus Sense LLC, Los Angeles, CA (United States)

    2013-09-10

    Black carbon (BC) emissions from traditional cooking fires and other sources are significant anthropogenic drivers of radiative forcing. Clean cookstoves present a more energy-efficient and cleaner-burning vehicle for cooking than traditional wood-burning stoves, yet many existing cookstoves reduce emissions by only modest amounts. Further research into cookstove use, fuel types, and verification of emissions is needed as adoption rates for such stoves remain low. Accelerated innovation requires techniques for measuring and verifying such cookstove performance. The overarching goal of the proposed program was to develop a low-cost, wireless instrument to provide a high-resolution profile of the cookstove BC emissions and usage in the field. We proposed transferring the complexity of analysis away from the sampling hardware at the measurement site and to software at a centrally located server to easily analyze data from thousands of sampling instruments. We were able to build a low-cost field-based instrument that produces repeatable, low-cost estimates of cookstove usage, fuel estimates, and emission values with low variability. Emission values from our instrument were consistent with published ranges of emissions for similar stove and fuel types.

  14. City-specific vehicle emission control strategies to achieve stringent emission reduction targets in China's Yangtze River Delta region.

    Science.gov (United States)

    Zhang, Shaojun; Wu, Ye; Zhao, Bin; Wu, Xiaomeng; Shu, Jiawei; Hao, Jiming

    2017-01-01

    The Yangtze River Delta (YRD) region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality. Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants (e.g., CO, HC and PM 2.5 ) in the YRD region. Even in Shanghai, where the emission control implemented are more stringent than in Jiangsu and Zhejiang, we observed little to no reduction in NOx emissions from 2000 to 2010. Emission-reduction targets for HC, NOx and PM 2.5 are determined using a response surface modeling tool for better air quality. We design city-specific emission control strategies for three vehicle-populated cities in the YRD region: Shanghai and Nanjing and Wuxi in Jiangsu. Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards, the limitation of vehicle population and usage, and the scrappage of older vehicles is applied, Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020. Therefore, additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles. Copyright © 2016. Published by Elsevier B.V.

  15. Laser-Based Diagnostic Measurements of Low Emissions Combustor Concepts

    Science.gov (United States)

    Hicks, Yolanda R.

    2011-01-01

    This presentation provides a summary of primarily laser-based measurement techniques we use at NASA Glenn Research Center to characterize fuel injection, fuel/air mixing, and combustion. The report highlights using Planar Laser-Induced Fluorescence, Particle Image Velocimetry, and Phase Doppler Interferometry to obtain fuel injector patternation, fuel and air velocities, and fuel drop sizes and turbulence intensities during combustion. We also present a brief comparison between combustors burning standard JP-8 Jet fuel and an alternative fuels. For this comparison, we used flame chemiluminescence and high speed imaging.

  16. Modelled impacts of mitigation measures on greenhouse gas emissions from Finnish agriculture up to 2020

    Directory of Open Access Journals (Sweden)

    K. REGINA

    2008-12-01

    Full Text Available Emission scenarios based on integrated quantitative modelling are a valuable tool in planning strategies for greenhouse gas mitigation. By estimating the potential of individual mitigation measures to reduce greenhouse gas emissions, resources can be targeted to the most promising policy measures. This paper reports two agricultural emission scenarios for Finland up to year 2020, one baseline scenario (Scenario 1 based on the projected agricultural production levels determined by markets and agricultural policy and one with selected mitigation measures included (Scenario 2. Measures selected for the analysis consisted of 1 keeping agricultural area at the current level, 2 decreasing the proportion of organic soils, 3 increasing the proportion of grass cultivation on organic soils and 4 supporting biogas production on farms. Starting from 2005, the emissions of nitrous oxide and methane from agriculture would decrease 2.3% in Scenario 1 by 2020 whereas the respective decrease would be 11.5% in Scenario 2. According to the results, mitigation measures targeted to cultivation of organic soils have the largest potential to reduce the emissions. Such measures would include reducing the area of cultivated organic soils and increasing the proportion of perennial crops on the remaining area.

  17. Airborne emission measurements of SO2 , NOx and particles from individual ships using a sniffer technique

    Science.gov (United States)

    Beecken, J.; Mellqvist, J.; Salo, K.; Ekholm, J.; Jalkanen, J.-P.

    2014-07-01

    A dedicated system for airborne ship emission measurements of SO2, NOx and particles has been developed and used from several small aircraft. The system has been adapted for fast response measurements at 1 Hz, and the use of several of the instruments is unique. The uncertainty of the given data is about 20% for SO2 and 24% for NOx emission factors. The mean values with one standard deviation for multiple measurements of 158 ships measured from the air on the Baltic and North Sea during 2011 and 2012 show emission factors of 18.8 ± 6.5 g kg-1 fuel , 66.6 ± 23.4 g kg-1 fuel and 1.8 ± 1.3 1016 particles kg-1 fuel for SO2, NOx and particle number, respectively. The particle size distributions were measured for particle diameters between 15 and 560 nm. The mean sizes of the particles are between 45 and 54 nm dependent on the distance to the source, and the number size distribution is monomodal. Concerning the sulfur fuel content, around 85% of the monitored ships comply with the International Maritime Organization (IMO) limits. The reduction of the sulfur emission control area (SECA) limit from 1.5 to 1% in 2010 appears to have contributed to reduction of sulfur emissions that were measured in earlier studies from 2007 to 2009. The presented method can be implemented for regular ship compliance monitoring.

  18. Acoustic emission measurements during impacts tests for determining ductile fracture data

    International Nuclear Information System (INIS)

    Richter, H.

    2000-09-01

    The document reports work for further development of methods and tests to obtain better information on the crack initiation toughness (J id ) under impact loading conditions, by acoustic emission measurements. The applicability of the acoustic emission tests for the given purpose was proven by instrumented Charpy tests using modified ISO-V specimens. The physical crack initiation toughness served as the reference value for reliable evaluation of the characteristic data obtained. This reference value is derived from the crack resistance curve determined by the multi-specimen cleavage fracture method combined with data from measurements of the stretching zone width. Verification of the acoustic emission-defined initiation value included a variety of tests, as e.g. additional dynamic single-specimen methods (L-COD, magnetic emission), and supplementary tests (D3PB, pendulum impact testing machine). The test materials are various steels with different strength/toughness properties. (orig./CB) [de

  19. Measurements of atmospheric hydrocarbons and biogenic emission fluxes in the Amazon boundary layer

    Science.gov (United States)

    Zimmerman, P. R.; Greenberg, J. P.; Westberg, C. E.

    1988-01-01

    Tropospheric mixing ratios of methane, C2-C10 hydrocarbons, and carbon monoxide were measured over the Amazon tropical forest near Manaus, Amazonas, Brazil, in July and August 1985. The measurements, consisting mostly of altitude profiles of these gases, were all made within the atmospheric boundary layer up to an altitude of 1000 m above ground level. Data characterize the diurnal hydrocarbon composition of the boundary layer. Biogenic emissions of isoprene control hydroxyl radical concentrations over the forest. Biogenic emission fluxes of isoprene and terpenes are estimated to be 25,000 micrograms/sq m per day and 5600 micrograms/sq m per day, respectively. This isoprene emission is equivalent to 2 percent of the net primary productivity of the tropical forest. Atmospheric oxidation of biogenic isoprene and terpenes emissions from the Amazon forest may account for daily increases of 8-13 ppb for carbon monoxide in the planetary boundary layer.

  20. Does trade matter for carbon emissions in OECD countries? Evidence from a new trade openness measure.

    Science.gov (United States)

    Gozgor, Giray

    2017-12-01

    This paper analyzes the impacts of the per capita income, the per capita energy consumption, and the trade openness on the level of per capita carbon emissions in the panel dataset of 35 Organization for Economic Cooperation and Development (OECD) countries over the period 1960-2013. Along with the nominal trade openness, the paper uses a different trade openness measure, so called as the "trade potential index" (TPI). To the best of our knowledge, this is the first paper that uses the TPI in the empirical environmental Kuznets curve (EKC) hypothesis literature. The paper finds that the EKC hypothesis is valid and there is an "inverted-U" relationship between the income and the carbon emissions. In addition, the paper observes that there is a positive effect of the energy consumption on the carbon emissions. Furthermore, the results indicate that both trade openness measures are negatively associated with the carbon emissions in the OECD countries in the long run.

  1. A method for measuring particle number emissions from vehicles driving on the road.

    Science.gov (United States)

    Shi, J P; Harrison, R M; Evans, D E; Alam, A; Barnes, C; Carter, G

    2002-01-01

    Earlier research has demonstrated that the conditions of dilution of engine exhaust gases profoundly influence the size distribution and total number of particles emitted. Since real world dilution conditions are variable and therefore difficult to simulate, this research has sought to develop and validate a method for measuring particle number emissions from vehicles driving past on a road. This has been achieved successfully using carbon dioxide as a tracer of exhaust gas dilution. By subsequent adjustment of data to a constant dilution factor, it is possible to compare emissions from different vehicles using different technologies and fuels based upon real world emission data. Whilst further optimisation of the technique, especially in terms of matching the instrument response times is desirable, the measurements offer useful insights into emissions from gasoline and diesel vehicles, and the substantial proportion of particles emitted in the 3-7 nanometre size range.

  2. Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement

    International Nuclear Information System (INIS)

    Masuda, Takahiko; Hara, Hideaki; Miyamoto, Yuki; Kuma, Susumu; Nakano, Itsuo; Ohae, Chiaki; Sasao, Noboru; Tanaka, Minoru; Uetake, Satoshi; Yoshimi, Akihiro; Yoshimura, Koji; Yoshimura, Motohiko

    2015-01-01

    We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10 15 from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect

  3. Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Takahiko, E-mail: masuda@okayama-u.ac.jp; Hara, Hideaki; Miyamoto, Yuki [Okayama University, Research Core for Extreme Quantum World (Japan); Kuma, Susumu [Atomic, Molecular and Optical Physics Laboratory, RIKEN (Japan); Nakano, Itsuo [Okayama University, Research Core for Extreme Quantum World (Japan); Ohae, Chiaki [University of Electro-Communications, Department of Engineering Science (Japan); Sasao, Noboru [Okayama University, Research Core for Extreme Quantum World (Japan); Tanaka, Minoru [Osaka University, Department of Physics (Japan); Uetake, Satoshi [Okayama University, Research Center of Quantum Universe (Japan); Yoshimi, Akihiro; Yoshimura, Koji [Okayama University, Research Core for Extreme Quantum World (Japan); Yoshimura, Motohiko [Okayama University, Research Center of Quantum Universe (Japan)

    2015-11-15

    We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10{sup 15} from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect.

  4. Measuring current emission and work functions of large thermionic cathodes

    International Nuclear Information System (INIS)

    Fortgang, C.M.

    2001-01-01

    As one component of the nations Stockpile Stewardship program, Los Alamos National Laboratory is constructing a 20 MeV, 2 kA (with a 4 kA upgrade capability), 3ps induction linac for doing x-ray radiography of explosive devices. The linac is one leg of a facility called the Dual-Axis Radiography Hydrodynamic Test Facility (DARHT). The electron gun is designed to operate at 3.2 MV. The gun is a Pierce type design and uses a 6.5' cathode for 2 kA operation and an 8' cathode for 4 kA operation. We have constructed a small facility called the Cathode Test Stand (CTS) to investigate engineering and physics issues regarding large thermionic dispenser-cathodes. In particular, we have looked at the issues of temperature uniformity on the cathode surface and cathode quality as measured by its work function. We have done thermal imaging of both 8' and 6.5' cathodes. Here we report on measurements of the cathode work function, both the average value and how it vanes across the face of the cathode.

  5. On-board measurements of emissions from light-duty gasoline vehicles in three mega-cities of China

    Science.gov (United States)

    Huo, Hong; Yao, Zhiliang; Zhang, Yingzhi; Shen, Xianbao; Zhang, Qiang; Ding, Yan; He, Kebin

    2012-03-01

    This paper is the second in a series of three papers aimed at understanding the emissions of vehicles in China by conducting on-board emission measurements. This paper focuses on light-duty gasoline vehicles. In this study, we measured 57 light-duty gasoline vehicles (LDGVs) in three Chinese mega-cites (Beijing, Guangzhou, and Shenzhen), covering Euro 0 through Euro IV technologies, and generated CO, HC, and NOx emission factors and deterioration rates for each vehicle technology. The results show that the vehicle emission standards have played a significant role in reducing vehicle emission levels in China. The vehicle emission factors are reduced by 47-81%, 53-64%, 46-71%, and 78-82% for each phase from Euro I to Euro IV. Euro 0 vehicles have a considerably high emission level, which is hundreds of times larger than that of Euro IV vehicles. Three old taxis and four other Euro I and Euro II LDGVs are also identified as super emitters with equivalent emission levels to Euro 0 vehicles. Of the measured fleet, 23% super emitters were estimated to contribute 50-80% to total emissions. Besides vehicle emission standards, measures for restricting super emitters are equally important to reduce vehicle emissions. This study is intended to improve the understanding of the vehicle emission levels in China, but some key issues such as emission deterioration rates are yet to be addressed with the presence of a sufficient amount of vehicle emission measurements.

  6. A dual tracer ratio method for comparative emission measurements in an experimental dairy housing

    Science.gov (United States)

    Mohn, Joachim; Zeyer, Kerstin; Keck, Margret; Keller, Markus; Zähner, Michael; Poteko, Jernej; Emmenegger, Lukas; Schrade, Sabine

    2018-04-01

    Agriculture, and in particular dairy farming, is an important source of ammonia (NH3) and non-carbon dioxide greenhouse gas (GHG) emissions. This calls for the development and quantification of effective mitigation strategies. Our study presents the implementation of a dual tracer ratio method in a novel experimental dairy housing with two identical, but spatially separated housing areas. Modular design and flexible floor elements allow the assessment of structural, process engineering and organisational abatement measures at practical scale. Thereby, the emission reduction potential of specific abatement measures can be quantified in relation to a reference system. Emissions in the naturally ventilated housing are determined by continuous dosing of two artificial tracers (sulphur hexafluoride SF6, trifluoromethylsulphur pentafluoride SF5CF3) and their real-time detection in the ppt range with an optimized GC-ECD method. The two tracers are dosed into different experimental sections, which enables the independent assessment of both housing areas. Mass flow emissions of NH3 and GHGs are quantified by areal dosing of tracer gases and multipoint sampling as well as real-time analysis of both tracer and target gases. Validation experiments demonstrate that the technique is suitable for both areal and point emission sources and achieves an uncertainty of less than 10% for the mass emissions of NH3, methane (CH4) and carbon dioxide (CO2), which is superior to other currently available methods. Comparative emission measurements in this experimental dairy housing will provide reliable, currently unavailable information on emissions for Swiss dairy farming and demonstrate the reduction potential of mitigation measures for NH3, GHGs and potentially other pollutants.

  7. Analysis of recent results of electron cyclotron emission measurements on T.F.R

    International Nuclear Information System (INIS)

    1977-05-01

    Recently reported measurements of the electron cyclotron emission from the TFR Tokamak plasma are analyzed and compared to theoretical predictions. The line shape of an optically thick harmonic in a vertical observation is explained by wall reflections, plasma-detector arrangement and reabsorption. Non thermal emission at the electron plasma frequency is related to the presence of a high energy tail in the electron distribution function and might be the cause of the observed reduced runaway creation rate

  8. Measurements of Dermal and Oral Emissions from Humans

    DEFF Research Database (Denmark)

    Tsushima, Sayana; Bekö, Gabriel; Bossi, Rossana

    2016-01-01

    Human related pollutants (bioeffluents) emitted through skin and via exhaled breath were measured. Two climate chambers were connected via flexible ducts. The ducts were in one chamber attached to a breathing mask, through which five subjects exhaled on one occasion the air into the other chamber......: Human bioeffluents emitted orally were in this way isolated from those that were emitted dermally. On another occasion, the subjects exhaled the air into the chamber where they were sitting, thus exposure contained oral and dermal bioeffluents. Another twenty subjects assessed the air quality...... in the chambers. They judged the air quality in the chamber with dermal bioeffluents to be lower than in the one containing orally exhaled bioeffluents, and similar to the air quality in the chamber with all bioeffluents. The chemical compounds with slightly elevated concentrations differed between the two...

  9. Quality Utilization Aware Based Data Gathering for Vehicular Communication Networks

    Directory of Open Access Journals (Sweden)

    Yingying Ren

    2018-01-01

    Full Text Available The vehicular communication networks, which can employ mobile, intelligent sensing devices with participatory sensing to gather data, could be an efficient and economical way to build various applications based on big data. However, high quality data gathering for vehicular communication networks which is urgently needed faces a lot of challenges. So, in this paper, a fine-grained data collection framework is proposed to cope with these new challenges. Different from classical data gathering which concentrates on how to collect enough data to satisfy the requirements of applications, a Quality Utilization Aware Data Gathering (QUADG scheme is proposed for vehicular communication networks to collect the most appropriate data and to best satisfy the multidimensional requirements (mainly including data gathering quantity, quality, and cost of application. In QUADG scheme, the data sensing is fine-grained in which the data gathering time and data gathering area are divided into very fine granularity. A metric named “Quality Utilization” (QU is to quantify the ratio of quality of the collected sensing data to the cost of the system. Three data collection algorithms are proposed. The first algorithm is to ensure that the application which has obtained the specified quantity of sensing data can minimize the cost and maximize data quality by maximizing QU. The second algorithm is to ensure that the application which has obtained two requests of application (the quantity and quality of data collection, or the quantity and cost of data collection could maximize the QU. The third algorithm is to ensure that the application which aims to satisfy the requirements of quantity, quality, and cost of collected data simultaneously could maximize the QU. Finally, we compare our proposed scheme with the existing schemes via extensive simulations which well justify the effectiveness of our scheme.

  10. Spectral emissivity measurements of candidate materials for very high temperature reactors

    Energy Technology Data Exchange (ETDEWEB)

    Cao, G.; Weber, S.J.; Martin, S.O.; Anderson, M.H. [Department of Engineering Physics, University of Wisconsin, 1500 Engineering Drive, Madison, WI (United States); Sridharan, K., E-mail: kumars@cae.wisc.edu [Department of Engineering Physics, University of Wisconsin, 1500 Engineering Drive, Madison, WI (United States); Allen, T.R. [Department of Engineering Physics, University of Wisconsin, 1500 Engineering Drive, Madison, WI (United States)

    2012-10-15

    Heat dissipation by radiation is an important consideration in VHTR components, particularly the reactor pressure vessel (RPV), because of the fourth power temperature dependence of radiated heat. Since emissivity is the material property that dictates the ability to radiate heat, measurements of emissivities of materials that are being specifically considered for the construction of VHTR become important. Emissivity is a surface phenomenon and therefore compositional, structural, and topographical changes that occur at the surfaces of these materials as a result of their interactions with the environment at high temperatures will alter their emissivities. With this background, an experimental system for the measurement of spectral emissivity has been designed and constructed. The system has been calibrated in conformance with U.S. DoE quality assurance standards using inert ceramic materials, boron nitride, silicon carbide, and aluminum oxide. The results of high temperature emissivity measurements of potential VHTR materials such as ferritic steels SA 508, T22, T91 and austenitic alloys IN 800H, Haynes 230, IN 617, and 316 stainless steel have been presented.

  11. 40 CFR 75.15 - Special provisions for measuring Hg mass emissions using the excepted sorbent trap monitoring...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Special provisions for measuring Hg... EMISSION MONITORING Monitoring Provisions § 75.15 Special provisions for measuring Hg mass emissions using... Federal Hg mass emission reduction program that adopts the provisions of subpart I of this part, if the...

  12. 75 FR 68575 - Revisions To In-Use Testing for Heavy-Duty Diesel Engines and Vehicles; Emissions Measurement and...

    Science.gov (United States)

    2010-11-08

    ... later model year vehicles when operated under a wide range of real world driving conditions.\\1\\ The... ``data driven'' emission measurement allowances through a comprehensive research, development, and... Vehicles; Emissions Measurement and Instrumentation; Not-to-Exceed Emission Standards; and Technical...

  13. Measuring and modeling of soil N2O emissions - How well are we doing?

    Science.gov (United States)

    Butterbach-Bahl, K.; Ralf, K.; Werner, C.; Wolf, B.

    2017-12-01

    Microbial processes in soils are the primarily source of atmospheric N2O. Fertilizer use to boost food and feed production of agricultural systems as well as nitrogen deposition to natural and semi-natural ecosystems due to emissions of NOx and NH3 from agriculture and energy production and re-deposition to terrestrial ecosystems has likely nearly doubled the pre-industrial source strength of soils for atmospheric N2O. Quantifying soil emissions and identifying mitigation options is becoming a major focus in the climate debate as N2O emissions from agricultural soils are a major contributor to the greenhouse gas footprint of agricultural systems, with agriculture incl. land use change contributing up to 30% to total anthropogenic GHG emissions. The increasing number of annual datasets show that soil emissions a) are largely depended on soil N availability and thus e.g. fertilizer application, b) vary with management (e.g. timing of fertilization, residue management, tillage), c) depend on soil properties such as organic matter content and pH, e) are affected by plant N uptake, and e) are controlled by environmental factors such as moisture and temperature regimes. It is remarkable that the magnitude of annual emissions is largely controlled by short-term N2O pulses occurring due to fertilization, wetting and drying or freezing and thawing of soils. All of this contributes to a notorious variability of soil N2O emissions in space and time. Overcoming this variability for quantification of source strengths and identifying tangible mitigation options requires targeted measuring approaches as well as the translation of our knowledge on mechanisms underlying emissions into process oriented models, which finally might be used for upscaling and scenario studies. This paper aims at reviewing current knowledge on measurements, modelling and upscaling of soil N2O emissions, thereby identifying short comes and uncertainties of the various approaches and fields for future

  14. Mobile measurement of methane emissions from natural gas developments in northeastern British Columbia, Canada

    Science.gov (United States)

    Atherton, Emmaline; Risk, David; Fougère, Chelsea; Lavoie, Martin; Marshall, Alex; Werring, John; Williams, James P.; Minions, Christina

    2017-10-01

    North American leaders recently committed to reducing methane emissions from the oil and gas sector, but information on current emissions from upstream oil and gas developments in Canada are lacking. This study examined the occurrence of methane plumes in an area of unconventional natural gas development in northwestern Canada. In August to September 2015 we completed almost 8000 km of vehicle-based survey campaigns on public roads dissecting oil and gas infrastructure, such as well pads and processing facilities. We surveyed six routes 3-6 times each, which brought us past over 1600 unique well pads and facilities managed by more than 50 different operators. To attribute on-road plumes to oil- and gas-related sources we used gas signatures of residual excess concentrations (anomalies above background) less than 500 m downwind from potential oil and gas emission sources. All results represent emissions greater than our minimum detection limit of 0.59 g s-1 at our average detection distance (319 m). Unlike many other oil and gas developments in the US for which methane measurements have been reported recently, the methane concentrations we measured were close to normal atmospheric levels, except inside natural gas plumes. Roughly 47 % of active wells emitted methane-rich plumes above our minimum detection limit. Multiple sites that pre-date the recent unconventional natural gas development were found to be emitting, and we observed that the majority of these older wells were associated with emissions on all survey repeats. We also observed emissions from gas processing facilities that were highly repeatable. Emission patterns in this area were best explained by infrastructure age and type. Extrapolating our results across all oil and gas infrastructure in the Montney area, we estimate that the emission sources we located (emitting at a rate > 0.59 g s-1) contribute more than 111 800 t of methane annually to the atmosphere. This value exceeds reported bottom

  15. Developing of risk-hedging CO2-emission policy. Part II: risks associated with measures to limit emissions, synthesis and conclusions

    International Nuclear Information System (INIS)

    Harvey, L.D.D.

    1996-01-01

    This paper is Part II of a two-part series in which the risk associated with unrestrained greenhouse-gas emissions, and with measures to limit emissions, are reviewed. The following risks associated with these efforts to limit CO 2 emissions are reviewed here: (1) resources might be diverted from other urgent needs; (2) economic growth might be reduced; (3) reduction measures might cost more than expected; (4) early action might cost more than later action; (5) reduction measures might have undesired side effects; (6) reduction measures might require heavy-handed government intervention; and (7) reduction measures might not work. With gradual implementation of a diversified portfolio of measures, these risks can be greatly reduced. Based on the review of risks associated with measures to limit emissions here, and the review of the risk associated with unrestrained emissions presented in Part I, it is concluded that a reasonable near-term (20-30 year) risk hedging strategy is one which seeks to stabilize global fossil CO 2 emissions at the present (early 1990s) level. This is turn implies an emission reduction of 26% for industrialized countries as a whole and 40-50% for Canada and the USA if developing country emissions are to increase by no more than 60%, which in itself would require major assistance from the industrialized countries. The framework and conclusions presented here are critically compared with so-called optimization frameworks. 82 refs., 2 figs., 2 tabs

  16. Botanical environmental monitors for zinc pollution resulting from vehicular traffic

    International Nuclear Information System (INIS)

    Altaf, W.J.

    2007-01-01

    Botanical samples were used as monitors for zinc pollution resulting from vehicular traffic. Euphorbia terracina and Calotropis procera were the botanical monitors used in this work. Zinc concentrations were reported alongside a motorway stretch of 50 km. Variations in concentration with respect to the perpendicular distance from the roadside were also reported. The effect of wind turbulence and the wind direction on the concentrations is discussed. In addition, differences between open areas and confined areas with respect to the elemental uptake were also discussed. INAA, using reactor neutrons, was employed for the determination of Zn concentrations in the samples. (author)

  17. Energy Efficient Wireless Vehicular-Guided Actuator Network

    KAUST Repository

    Boudellioua, Imene

    2013-06-09

    In this paper, we present an energy-efficient vehicular guided system for environmental disaster management using wireless sensor/actuator networks. Sensor nodes within clusters are controlled by a master node that is dynamically selected. Actuators support mobility for every sensor node in the area of interest. The system maintains energy efficiency using statistical, correlation, and confidence for determining actuator actions and implements an adaptive energy scheme to prolong the system lifespan. Experimental results show that the system is capable of saving up to 2.7Watt for every 28KByte of data exchanged. We also show that actuator actions are correct with a 90% confidence.

  18. Real-time monitoring of emissions with traffic data, simulation and air quality measurements

    NARCIS (Netherlands)

    Klunder, G.A.; Wilmink, I.R.

    2009-01-01

    This paper investigates the possibility to decide when to apply a (dynamic) traffic management measure to improve the air quality or reduce CO2 emissions, based on a limited set of (measured) data. It is expected that a combination of monitoring and modeling is needed for reliable air quality

  19. Optimization of distortion product otoacoustic emission (DPOAE) measurements with the system IL096

    DEFF Research Database (Denmark)

    de Toro, Miguel Angel Aranda; Ordoñez, Rodrigo Pizarro; Hammershøi, Dorte

    2007-01-01

    Measurements of distortion product otoacoustic emissions (DPOAEs) at Aalborg University are performed with the commercial system ILO96 from Otodynamics. The default measuring setup is not adequate for monitoring the recovery of DPOAEs after noise exposure because (1) data collection is interrupte...

  20. Development of a portable remote sensing system for measurement of diesel emissions from passing diesel trucks.

    Science.gov (United States)

    2011-04-08

    A wireless remote-sensing system has been developed for measurement of NOx and particulate matters (PM) emissions from passing diesel trucks. The NOx measurement system has a UV light source with quartz fiber optics that focused the light source into...

  1. Measurements of air pollution emission factors for marine transportation in SECA

    NARCIS (Netherlands)

    Alföldy, B.; Lööv, J.; Lagler, F.; Mellqvist, J.; Berg, N.; Beecken, J.; Weststrate, J.H.; Duyzer, J.H.; Bencs, L.; Horemans, B.; Cavalli, F.; Putaud, J.P.; Janssens-Maenhout, G.; Csordas, A.P.; Grieken, R. van; Borowiak, A.; Hjorth, J.

    2013-01-01

    The chemical composition of the plumes of seagoing ships was measured during a two week long measure- ment campaign in the port of Rotterdam, Hoek van Holland The Netherlands, in September 2009. Altogether, 497 ships were monitored and a statistical evaluation of emission factors (g kg−1 fuel) was

  2. [Air Dielectric Barrier Discharge Emission Spectrum Measurement and Particle Analysis of Discharge Process].

    Science.gov (United States)

    Shen, Shuang-yan; Jin, Xing; Zhang, Peng

    2016-02-01

    The emission spectrum detection and diagnosis is one of the most common methods of application to the plasma. It provides wealth of information of the chemical and physical process of the plasma. The analysis of discharge plasma dynamic behavior plays an important role in the study of gas discharge mechanism and application. An air dielectric discharge spectrum measuring device was designed and the emission spectrum data was measured under the experimental condition. The plasma particles evolution was analyzed from the emission spectrum. The numerical calculation model was established and the density equation, energy transfer equation and the Boltzmann equation was coupled to analyze the change of the particle density to explain the emission spectrum characteristics. The results are that the particle density is growing with the increasing of reduced electric field. The particle density is one or two orders of magnitude difference for the same particle at the same moment for the reduced electric field of 40, 60 or 80 Td. A lot of N₂ (A³), N₂ (A³) and N₂ (C³) particles are generated by the electric field excitation. However, it transforms quickly due to the higher energy level. The transformation returns to the balance after the discharge of 10⁻⁶ s. The emission spectrometer measured in the experiments is mostly generated by the transition of excited nitrogen. The peak concentration of O₂ (A¹), O₂ (B¹) and O₂ (A³ ∑⁺u) is not low compared to the excited nitrogen molecules. These particles energy is relatively low and the transition spectral is longer. The spectrometer does not capture the oxygen emission spectrum. And the peak concentration of O particles is small, so the transition emission spectrum is weak. The calculation results of the stabled model can well explain the emission spectrum data.

  3. Health impact assessment of ambient fine particulate matter exposure in impacts by different vehicle control measures in China

    Science.gov (United States)

    LI, S.; Wang, H.; Jiang, F.; Zhang, S.

    2017-12-01

    Road transportation is the one of the largest emission sources contributing to ambient PM2.5 pollution in China. Since the 1990s, China has adopted comprehensive control measures to mitigate vehicle emissions. However, the effects of these measures on reducing emissions, improving air quality and avoiding negative health impacts have not been systematically evaluated. In this study, we combine emissions inventory, air quality modeling, and IER model to evaluate the effect of various vehicle control measures on premature deaths attributable to ambient PM2.5 at a spatial resolution of 36 km × 36 km across China. Our results show that, comparing to no control scenarios, the total vehicular emissions with the actual vehicle emission controls implemented have reduced the emissions of NOX, HC, CO, PM2.5 by 57%, 69%, 75%, 71% respectively; and reduced the national annual mean PM2.5 concentration by 2.5ug/m³ across China by 2010. The number of avoidable deaths associated with reducing PM2.5 level is 150 thousands (95% Confidence interval: 66 thousand - 212 thousand). The geographic distribution of the absolute number of avoidable deaths presents a distinct regional feature and is particularly evident in several regions. The most influential areas are mainly concentrated in Beijing and its south part, which formed a large area of continuous high value. Our results have important policy implications on prioritizing vehicular emission control strategy in China.

  4. Removing traffic emissions from CO2 time series measured at a tall tower using mobile measurements and transport modeling

    Science.gov (United States)

    Schmidt, Andres; Rella, Chris W.; Göckede, Mathias; Hanson, Chad; Yang, Zhenlin; Law, Beverly E.

    2014-11-01

    In recent years, measurements of atmospheric carbon dioxide with high precision and accuracy have become increasingly important for climate change research, in particular to inform terrestrial biosphere models. Anthropogenic carbon dioxide emissions from fossil fuel burning have long been recognized to contribute a significant portion of the carbon dioxide in the atmosphere. Here, we present an approach to remove the traffic related carbon dioxide emissions from mole fractions measured at a tall tower by using the corresponding carbon monoxide measurements in combination with footprint analyses and transport modeling. This technique improves the suitability of the CO2 data to be used in inverse modeling approaches of atmosphere-biosphere exchange that do not account for non-biotic portions of CO2. In our study region in Oregon, road traffic emissions are the biggest source of anthropogenic carbon dioxide and carbon monoxide. A three-day mobile campaign covering 1700 km of roads in northwestern Oregon was performed during summer of 2012 using a laser-based Cavity Ring-Down Spectrometer. The mobile measurements incorporated different roads including main highways, urban streets, and back-roads, largely within the typical footprint of a tall CO/CO2 observation tower in Oregon's Willamette Valley. For the first time, traffic related CO:CO2 emission ratios were measured directly at the sources during an on-road campaign under a variety of different driving conditions. An average emission ratio of 7.43 (±1.80) ppb CO per ppm CO2 was obtained for the study region and applied to separate the traffic related portion of CO2 from the mole fraction time series. The road traffic related portion of the CO2 mole fractions measured at the tower site reached maximum values ranging from 9.8 to 12 ppm, depending on the height above the surface, during summer 2012.

  5. Pre-Harvest Sugarcane Burning: Determination of Emission Factors through Laboratory Measurements

    Directory of Open Access Journals (Sweden)

    João Andrade Carvalho

    2012-02-01

    Full Text Available Sugarcane is an important crop for the Brazilian economy and roughly 50% of its production is used to produce ethanol. However, the common practice of pre-harvest burning of sugarcane straw emits particulate material, greenhouse gases, and tropospheric ozone precursors to the atmosphere. Even with policies to eliminate the practice of pre-harvest sugarcane burning in the near future, there is still significant environmental damage. Thus, the generation of reliable inventories of emissions due to this activity is crucial in order to assess their environmental impact. Nevertheless, the official Brazilian emissions inventory does not presently include the contribution from pre-harvest sugarcane burning. In this context, this work aims to determine sugarcane straw burning emission factors for some trace gases and particulate material smaller than 2.5 μm in the laboratory. Excess mixing ratios for CO2, CO, NOX, UHC (unburned hydrocarbons, and PM2.5 were measured, allowing the estimation of their respective emission factors. Average estimated values for emission factors (g kg−1 of burned dry biomass were 1,303 ± 218 for CO2, 65 ± 14 for CO, 1.5 ± 0.4 for NOX, 16 ± 6 for UHC, and 2.6 ± 1.6 for PM2.5. These emission factors can be used to generate more realistic emission inventories and therefore improve the results of air quality models.

  6. Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall

    Energy Technology Data Exchange (ETDEWEB)

    Maddalena, Randy; Russell, Marion; Apte, Michael G.

    2010-06-01

    Imported drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. To support an investigation of those building materials by the Consumer Products Safety Commission (CPSC), Lawrence Berkeley National Laboratory (LBNL) measured chemical-specific emission factors for 30 samples of drywall materials. Emission factors are reported for 75 chemicals and 30 different drywall samples encompassing both domestic and imported stock and incorporating natural, synthetic, or mixed gypsum core material. CPSC supplied all drywall materials. First the drywall samples were isolated and conditioned in dedicated chambers, then they were transferred to small chambers where emission testing was performed. Four sampling and analysis methods were utilized to assess (1) volatile organic compounds, (2) low molecular weight carbonyls, (3) volatile sulfur compounds, and (4) reactive sulfur gases. LBNL developed a new method that combines the use of solid phase microextraction (SPME) with small emission chambers to measure the reactive sulfur gases, then extended that technique to measure the full suite of volatile sulfur compounds. The testing procedure and analysis methods are described in detail herein. Emission factors were measured under a single set of controlled environmental conditions. The results are compared graphically for each method and in detailed tables for use in estimating indoor exposure concentrations.

  7. On-board measurement of emissions from liquefied petroleum gas, gasoline and diesel powered passenger cars in Algeria

    OpenAIRE

    Chikhi , Saâdane; Boughedaoui , Ménouèr; Kerbachi , Rabah; Joumard , Robert

    2014-01-01

    International audience; On-board measurements of unit emissions of CO, HC, NOx and CO 2 were conducted on 17 private cars powered by different types of fuels including gasoline, dual gasoline-LPG, gasoline, and diesel. The tests performed revealed the effect of LPG injection technology on unit emissions and made it possible to compare the measured emissions to the European Artemis emission model. A sequential multipoint injection LPG kit with no catalyst installed was found to be the most eff...

  8. Diagnostic of the temperature and differential emission measure (DEM based on Hinode/XRT data

    Directory of Open Access Journals (Sweden)

    P. Rudawy

    2008-10-01

    Full Text Available We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present the determination of the temperature distribution of the X-rays emitting plasma using a filters ratio method and three various methods of the calculation of the differential emission measure (DEM. We have found that all these methods give results similar to the two filters ratio method. Additionally, all methods of the DEM calculation gave similar solutions. We can state that the majority of the pairs of the Hinode filters allows one to derive the temperature and emission measure in the isothermal plasma approximation using standard diagnostics based on the two filters ratio method. In cases of strong flares one can also expect good conformity of the results obtained using a Withbroe – Sylwester, genetic algorithm and least-squares methods of the DEM evaluation.

  9. Methods and techniques for measuring gas emissions from agricultural and animal feeding operations.

    Science.gov (United States)

    Hu, Enzhu; Babcock, Esther L; Bialkowski, Stephen E; Jones, Scott B; Tuller, Markus

    2014-01-01

    Emissions of gases from agricultural and animal feeding operations contribute to climate change, produce odors, degrade sensitive ecosystems, and pose a threat to public health. The complexity of processes and environmental variables affecting these emissions complicate accurate and reliable quantification of gas fluxes and production rates. Although a plethora of measurement technologies exist, each method has its limitations that exacerbate accurate quantification of gas fluxes. Despite a growing interest in gas emission measurements, only a few available technologies include real-time, continuous monitoring capabilities. Commonly applied state-of-the-art measurement frameworks and technologies were critically examined and discussed, and recommendations for future research to address real-time monitoring requirements for forthcoming regulation and management needs are provided.

  10. Sensitivity of Emissions to Uncertainties in Residual Gas Fraction Measurements in Automotive Engines: A Numerical Study

    Directory of Open Access Journals (Sweden)

    S. M. Aithal

    2018-01-01

    Full Text Available Initial conditions of the working fluid (air-fuel mixture within an engine cylinder, namely, mixture composition and temperature, greatly affect the combustion characteristics and emissions of an engine. In particular, the percentage of residual gas fraction (RGF in the engine cylinder can significantly alter the temperature and composition of the working fluid as compared with the air-fuel mixture inducted into the engine, thus affecting engine-out emissions. Accurate measurement of the RGF is cumbersome and expensive, thus making it hard to accurately characterize the initial mixture composition and temperature in any given engine cycle. This uncertainty can lead to challenges in accurately interpreting experimental emissions data and in implementing real-time control strategies. Quantifying the effects of the RGF can have important implications for the diagnostics and control of internal combustion engines. This paper reports on the use of a well-validated, two-zone quasi-dimensional model to compute the engine-out NO and CO emission in a gasoline engine. The effect of varying the RGF on the emissions under lean, near-stoichiometric, and rich engine conditions was investigated. Numerical results show that small uncertainties (~2–4% in the measured/computed values of the RGF can significantly affect the engine-out NO/CO emissions.

  11. North American pollution measurements from geostationary orbit with Tropospheric Emissions: Monitoring of Pollution (TEMPO)

    Science.gov (United States)

    Chance, K.

    2017-12-01

    TEMPO is the first NASA Earth Venture Instrument. It launches between 2019 and 2021 to measure atmospheric pollution from Mexico City and Cuba to the Canadian oil sands, and from the Atlantic to the Pacific, hourly at high spatial resolution, 10 km2. Geostationary daytime measurements capture the variability in the diurnal cycle of emissions and chemistry at sub-urban scale to improve emission inventories, monitor population exposure, and enable emission-control strategies.TEMPO measures UV/visible Earth reflectance spectra to retrieve O3, NO2, SO2, H2CO, C2H2O2, H2O, BrO, OClO, IO, aerosols, cloud parameters, and UVB radiation. It tracks aerosol loading. It provides near-real-time air quality products. TEMPO is the North American component of the upcoming the global geostationary constellation for pollution monitoring, together with the European Sentinel-4 and the Korean Geostationary Environmental Monitoring Spectrometer (GEMS).TEMPO science studies include: Intercontinental pollution transport; Solar-induced fluorescence from chlorophyll over land and in the ocean to study tropical dynamics, primary productivity and carbon uptake, to detect red tides, and to study phytoplankton; measurements of stratospheric intrusions that cause air quality exceedances; measurements at peaks in vehicle travel to capture the variability in emissions from mobile sources; measurements of thunderstorm activity, including outflow regions to better quantify lightning NOx and O3 production; cropland measurements to follow the temporal evolution of emissions after fertilizer application and from rain-induced emissions from semi-arid soils; investigating the chemical processing of primary fire emissions and the secondary formation of VOCs and ozone; examining ocean halogen emissions and their impact on the oxidizing capacity of coastal environments; measuring spectra of nighttime lights as markers for human activity, energy conservation, and compliance with outdoor lighting standards

  12. Identification studies about take measures for mitigate of gas emissions greenhouse effect in energy Sector

    International Nuclear Information System (INIS)

    1999-11-01

    In the Unit Nations Convention about Climatic change has get stability of greenhouse effects in atmosphere concentrations. In the framework to Uruguay Project URU/95/631 have been defined the need to identify, measures, practices, process and technologies for reduce some emissions furthermore in Energy sector. Emission impact, cost-benefit, direct or iundirect, national programs, factibility such as social, politics and Institutional agreements was considered in the present work. It was given emissions proyected for 15 years period 1999-2013 of the following atmospheric pollutants: carbon dioxide,carbon monoxide, nitrogen oxides, sulfur oxides and methane.Eight stages was applied the emission evaluation: natural gas; without natural gas; transport; industrial; Montevidean bus- car demand; natural gas uses in bus-taxi; nitrogen oxides control in thermic centrals; catalytic converters in gasoline cars

  13. Final report for measurement of primary particulate matter emissions from light-duty motor vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Norbeck, J. M.; Durbin, T. D.; Truex, T. J.

    1998-12-31

    This report describes the results of a particulate emissions study conducted at the University of California, Riverside, College of Engineering-Center for Environmental Research and Technology (CE-CERT) from September of 1996 to August of 1997. The goal of this program was to expand the database of particulate emissions measurements from motor vehicles to include larger numbers of representative in-use vehicles. This work was co-sponsored by the Coordinating Research Council (CRC), the South Coast Air Quality Management District (SCAQMD), and the National Renewable Energy Laboratory (NREL) and was part of a larger study of particulate emissions being conducted in several states under sponsorship by CRC. For this work, FTP particulate mass emission rates were determined for gasoline and diesel vehicles, along with the fractions of particulates below 2.5 and 10 microns aerodynamic diameter. A total of 129 gasoline-fueled vehicles and 19 diesel-fueled vehicles were tested as part of the program.

  14. Low-background measurements of neutron emission from Ti metal in pressurized deuterium gas

    International Nuclear Information System (INIS)

    Menlove, H.O.; Paciotti, M.A.; Claytor, T.N.; Tuggle, D.G.

    1991-01-01

    A wide variety of neutron detector systems have been used at various research facilities to search for anomalous neutron emission from deuterated metals. Some of these detector systems are summarized here together with possible sources of spurious signals from electronic noise. During the past two years, we have performed experiments to measure neutron emission from pressurized D 2 gas mixed with various forms of titanium metal chips and sponge. Details concerning the neutron detectors, experimental procedures, and results have been reported previously. Our recent experiments have focused on increasing the low-level neutron emission and finding a way to trigger the emission. To improve our detection sensitivity, we have increased the shielding in our counting laboratory, changed to low-background 3 He tubes, and set up additional detector systems in deep underground counting stations. This report is an update on this experimental work. 7 refs., 5 figs., 4 tabs

  15. Measurement of emission and deposition patterns of ammonia from urine in grass swards

    Science.gov (United States)

    Ross, C. A.; Jarvis, S. C.

    Currently, legislation is being considered to reduce NH3 emissions in the UK. The major sources of NH3 and their relative contributions are well known, however, the processes that control the rates of emission are still poorly defined. A series of wind-tunnel experiments has been carried out to determine the effects of various management practices on NH3 losses. The tunnels were modified to enable NH3 emission and subsequent deposition to the adjacent swards in the field to be measured. The wind-tunnels were used to examine the effects of herbage length, cutting and N status on rates of NH3 fluxes, which together with the prevailing environmental conditions affected the rates of NH3 emission and deposition. Results showed that between 20 and 60% of the NH3 emitted was deposited within 2 m. Compensation points of between 1.0 and 2.3 μg m-3 were calculated for the grass sward.

  16. 2nd International Workshop on Vehicular Adhoc Networks for Smart Cities 2016

    CERN Document Server

    Qayyum, Amir; Saad, Mohamad

    2017-01-01

    This book presents selected articles from the Second International Workshop on Vehicular Adhoc Networks for Smart Cities, 2016 (IWVSC’2016). In order to promote further research activities and challenges, it highlights recent developments in vehicular networking technologies and their role in future smart cities.

  17. The Indianapolis Flux Experiment (INFLUX: A test-bed for developing urban greenhouse gas emission measurements

    Directory of Open Access Journals (Sweden)

    Kenneth J. Davis

    2017-05-01

    Full Text Available The objective of the Indianapolis Flux Experiment (INFLUX is to develop, evaluate and improve methods for measuring greenhouse gas (GHG emissions from cities. INFLUX’s scientific objectives are to quantify CO2 and CH4 emission rates at 1 km2 resolution with a 10% or better accuracy and precision, to determine whole-city emissions with similar skill, and to achieve high (weekly or finer temporal resolution at both spatial resolutions. The experiment employs atmospheric GHG measurements from both towers and aircraft, atmospheric transport observations and models, and activity-based inventory products to quantify urban GHG emissions. Multiple, independent methods for estimating urban emissions are a central facet of our experimental design. INFLUX was initiated in 2010 and measurements and analyses are ongoing. To date we have quantified urban atmospheric GHG enhancements using aircraft and towers with measurements collected over multiple years, and have estimated whole-city CO2 and CH4 emissions using aircraft and tower GHG measurements, and inventory methods. Significant differences exist across methods; these differences have not yet been resolved; research to reduce uncertainties and reconcile these differences is underway. Sectorally- and spatially-resolved flux estimates, and detection of changes of fluxes over time, are also active research topics. Major challenges include developing methods for distinguishing anthropogenic from biogenic CO2 fluxes, improving our ability to interpret atmospheric GHG measurements close to urban GHG sources and across a broader range of atmospheric stability conditions, and quantifying uncertainties in inventory data products. INFLUX data and tools are intended to serve as an open resource and test bed for future investigations. Well-documented, public archival of data and methods is under development in support of this objective.

  18. Vehicular air pollution and environmental tax law in Brazil: proposed tax restructuring for sustainable development

    Directory of Open Access Journals (Sweden)

    Pedro Monteiro Machado de Almeida Penna

    2013-12-01

    Full Text Available This work presents a restructuring of taxes in the automotive sector in Brazil in order to foster sustainable development. Personal vehicles, trucks or buses emit gases that contribute to global warming and cause human health problems. There are policies in Brazil to reduce the emission of air pollutants from vehicles; however, these neither punish the polluter nor provide for damage compensation. The Tax Law, with the Constitutional Polluter Pays Principle, is an efficient instrument for State intervention in the economy. The work compared environmental and economic views regarding fuel and both personal and public vehicles. We estimated the environmental benefits of recycling vehicles in use more than 10 years, taking into consideration pollution engendered in the manufacture of a new vehicle. Finally, we propose to unify vehicular taxation when the vehicle is acquired, by ending the ICMS and PIS / COFINS taxes on fuels and instead taxing CIDE-fuels, without reducing overall collection by the Brazilian government. The ensuing revenue would be used for repairing environmental damages. We have also made suggestions for the improvement of public policies to control emissions of atmospheric pollutants.

  19. An Analysis of the Privacy Threat in Vehicular Ad Hoc Networks due to Radio Frequency Fingerprinting

    Directory of Open Access Journals (Sweden)

    Gianmarco Baldini

    2017-01-01

    Full Text Available In Vehicular Ad Hoc Networks (VANETs used in the road transportation sector, privacy risks may arise because vehicles could be tracked on the basis of the information transmitted by the Vehicle to Vehicle (V2V and Vehicle to Infrastructure (V2I communications implemented with the Dedicated Short Range Communications (DSRC standards operating at 5.9 GHz. Various techniques have been proposed in the literature to mitigate these privacy risks including the use of pseudonym schemes, but they are mostly focused on data anonymization at the network and application layer. At the physical layer, the capability to accurately identify and fingerprint wireless devices through their radio frequency (RF emissions has been demonstrated in the literature. This capability may generate a privacy threat because vehicles can be tracked using the RF emissions of their DSRC devices. This paper investigates the privacy risks related to RF fingerprinting to determine if privacy breaches are feasible in practice. In particular, this paper analyzes the tracking accuracy in challenging RF environments with high attenuation and fading.

  20. Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles.

    Science.gov (United States)

    Brady, James M; Crisp, Timia A; Collier, Sonya; Kuwayama, Toshihiro; Forestieri, Sara D; Perraud, Véronique; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D; Bertram, Timothy H

    2014-10-07

    Exposure to gas-phase isocyanic acid (HNCO) has been previously shown to be associated with the development of atherosclerosis, cataracts and rheumatoid arthritis. As such, accurate emission inventories for HNCO are critical for modeling the spatial and temporal distribution of HNCO on a regional and global scale. To date, HNCO emission rates from light duty gasoline vehicles, operated under driving conditions, have not been determined. Here, we present the first measurements of real-time emission factors of isocyanic acid from a fleet of eight light duty gasoline-powered vehicles (LDGVs) tested on a chassis dynamometer using the Unified Driving Cycle (UC) at the California Air Resources Board (CARB) Haagen-Smit test facility, all of which were equipped with three-way catalytic converters. HNCO emissions were observed from all vehicles, in contrast to the idealized laboratory measurements. We report the tested fleet averaged HNCO emission factors, which depend strongly on the phase of the drive cycle; ranging from 0.46 ± 0.13 mg kg fuel(-1) during engine start to 1.70 ± 1.77 mg kg fuel(-1) during hard acceleration after the engine and catalytic converter were warm. The tested eight-car fleet average fuel based HNCO emission factor was 0.91 ± 0.58 mg kg fuel(-1), within the range previously estimated for light duty diesel-powered vehicles (0.21-3.96 mg kg fuel(-1)). Our results suggest that HNCO emissions from LDGVs represent a significant emission source in urban areas that should be accounted for in global and regional models.

  1. A multitower measurement network estimate of California's methane emissions

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Seongeun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Hsu, Ying-Kuang [California Air Resources Board, Sacramento, CA (United States); Andrews, Arlyn E. [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). Earth System Research Lab.; Bianco, Laura [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). Earth System Research Lab.; Univ. of Colorado, Boulder, CO (United States). Cooperative Inst. for Research in Environmental Sciences; Vaca, Patrick [California Air Resources Board, Sacramento, CA (United States); Wilczak, James M. [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). Earth System Research Lab.; Fischer, Marc L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; California State Univ. (CalState East Bay), Hayward, CA (United States). Dept. of Anthropology, Geography and Environmental Studies

    2013-09-20

    In this paper, we present an analysis of methane (CH4) emissions using atmospheric observations from five sites in California's Central Valley across different seasons (September 2010 to June 2011). CH4 emissions for spatial regions and source sectors are estimated by comparing measured CH4 mixing ratios with transport model (Weather Research and Forecasting and Stochastic Time-Inverted Lagrangian Transport) predictions based on two 0.1° CH4 (seasonally varying “California-specific” (California Greenhouse Gas Emission Measurements, CALGEM) and a static global (Emission Database for Global Atmospheric Research, release version 42, EDGAR42)) prior emission models. Region-specific Bayesian analyses indicate that for California's Central Valley, the CALGEM- and EDGAR42-based inversions provide consistent annual total CH4 emissions (32.87 ± 2.09 versus 31.60 ± 2.17 Tg CO2eq yr-1; 68% confidence interval (CI), assuming uncorrelated errors between regions). Summing across all regions of California, optimized CH4 emissions are only marginally consistent between CALGEM- and EDGAR42-based inversions (48.35 ± 6.47 versus 64.97 ± 11.85 Tg CO2eq), because emissions from coastal urban regions (where landfill and natural gas emissions are much higher in EDGAR than CALGEM) are not strongly constrained by the measurements. Combining our results with those from a recent study of the South Coast Air Basin narrows the range of estimates to 43–57 Tg CO2eq yr-1 (1.3–1.8 times higher than the current state inventory). Finally, these results suggest that the combination of rural and urban measurements will be necessary to verify future changes in California's total CH4 emissions.

  2. Airborne emission measurements of SO2, NOx and particles from individual ships using sniffer technique

    Science.gov (United States)

    Beecken, J.; Mellqvist, J.; Salo, K.; Ekholm, J.; Jalkanen, J.-P.

    2013-12-01

    A dedicated system for airborne ship emission measurements of SO2, NOx and particles has been developed and used from several small aircrafts. The system has been adapted for fast response measurements at 1 Hz and the use of several of the instruments is unique. The uncertainty of the given data is about 20.3% for SO2 and 23.8% for NOx emission factors. Multiple measurements of 158 ships measured from the air on the Baltic and North Sea during 2011 and 2012 show emission factors of 18.8 ± 6.5 g kgfuel-1, 66.6 ± 23.4 g kgfuel-1, and 1.8 ± 1.3 × 1016 particles kgfuel-1 for SO2, NOx and particle number respectively. The particle size distributions were measured for particle diameters between 15 and 560 nm. The mean sizes of the particles are between 50 and 62 nm dependent on the distance to the source and the number size distribution is mono-modal. Concerning the sulfur fuel content 85% of the ships comply with the IMO limits. The sulfur emission has decreased compared to earlier measurements from 2007 to 2009. The presented method can be implemented for regular ship compliance monitoring.

  3. Broadcasted Location-Aware Data Cache for Vehicular Application

    Directory of Open Access Journals (Sweden)

    Fukuda Akira

    2007-01-01

    Full Text Available There has been increasing interest in the exploitation of advances in information technology, for example, mobile computing and wireless communications in ITS (intelligent transport systems. Classes of applications that can benefit from such an infrastructure include traffic information, roadside businesses, weather reports, entertainment, and so on. There are several wireless communication methods currently available that can be utilized for vehicular applications, such as cellular phone networks, DSRC (dedicated short-range communication, and digital broadcasting. While a cellular phone network is relatively slow and a DSRC has a very small communication area, one-segment digital terrestrial broadcasting service was launched in Japan in 2006, high-performance digital broadcasting for mobile hosts has been available recently. However, broadcast delivery methods have the drawback that clients need to wait for the required data items to appear on the broadcast channel. In this paper, we propose a new cache system to effectively prefetch and replace broadcast data using "scope" (an available area of location-dependent data and "mobility specification" (a schedule according to the direction in which a mobile host moves. We numerically evaluate the cache system on the model close to the traffic road environment, and implement the emulation system to evaluate this location-aware data delivery method for a concrete vehicular application that delivers geographic road map data to a car navigation system.

  4. Vehicular Visible Light Networks for Urban Mobile Crowd Sensing

    Directory of Open Access Journals (Sweden)

    Barbara M. Masini

    2018-04-01

    Full Text Available Crowd sensing is a powerful tool to map and predict interests and events. In the future, it could be boosted by an increasing number of connected vehicles sharing information and intentions. This will be made available by on board wireless connected devices able to continuously communicate with other vehicles and with the environment. Among the enabling technologies, visible light communication (VLC represents a low cost solution in the short term. In spite of the fact that vehicular communications cannot rely on the sole VLC due to the limitation provided by the light which allows communications in visibility only, VLC can however be considered to complement other wireless communication technologies which could be overloaded in dense scenarios. In this paper we evaluate the performance of VLC connected vehicles when urban crowd sensing is addressed and we compare the performance of sole vehicular visible light networks with that of VLC as a complementary technology of IEEE 802.11p. Results, obtained through a realistic simulation tool taking into account both the roadmap constraints and the technologies protocols, help to understand when VLC provides the major improvement in terms of delivered data varying the number and position of RSUs and the FOV of the receiver.

  5. Achieve Location Privacy-Preserving Range Query in Vehicular Sensing.

    Science.gov (United States)

    Kong, Qinglei; Lu, Rongxing; Ma, Maode; Bao, Haiyong

    2017-08-08

    Modern vehicles are equipped with a plethora of on-board sensors and large on-board storage, which enables them to gather and store various local-relevant data. However, the wide application of vehicular sensing has its own challenges, among which location-privacy preservation and data query accuracy are two critical problems. In this paper, we propose a novel range query scheme, which helps the data requester to accurately retrieve the sensed data from the distributive on-board storage in vehicular ad hoc networks (VANETs) with location privacy preservation. The proposed scheme exploits structured scalars to denote the locations of data requesters and vehicles, and achieves the privacy-preserving location matching with the homomorphic Paillier cryptosystem technique. Detailed security analysis shows that the proposed range query scheme can successfully preserve the location privacy of the involved data requesters and vehicles, and protect the confidentiality of the sensed data. In addition, performance evaluations are conducted to show the efficiency of the proposed scheme, in terms of computation delay and communication overhead. Specifically, the computation delay and communication overhead are not dependent on the length of the scalar, and they are only proportional to the number of vehicles.

  6. An Adaptive Channel Model for VBLAST in Vehicular Networks

    Directory of Open Access Journals (Sweden)

    Ghassan M. T. Abdalla

    2009-01-01

    Full Text Available The wireless transmission environment in vehicular ad hoc systems varies from line of sight with few surroundings to rich Rayleigh fading. An efficient communication system must adapt itself to these diverse conditions. Multiple antenna systems are known to provide superior performance compared to single antenna systems in terms of capacity and reliability. The correlation between the antennas has a great effect on the performance of MIMO systems. In this paper we introduce a novel adaptive channel model for MIMO-VBLAST systems in vehicular ad hoc networks. Using the proposed model, the correlation between the antennas was investigated. Although the line of sight is ideal for single antenna systems, it severely degrades the performance of VBLAST systems since it increases the correlation between the antennas. A channel update algorithm using single tap Kalman filters for VBLAST in flat fading channels has also been derived and evaluated. At 12 dB Es/N0, the new algorithm showed 50% reduction in the mean square error (MSE between the actual channel and the corresponding updated estimate compared to the MSE without update. The computational requirement of the proposed algorithm for a p×q VBLAST is 6p×q real multiplications and 4p×q real additions.

  7. Broadcasted Location-Aware Data Cache for Vehicular Application

    Directory of Open Access Journals (Sweden)

    Kenya Sato

    2007-05-01

    Full Text Available There has been increasing interest in the exploitation of advances in information technology, for example, mobile computing and wireless communications in ITS (intelligent transport systems. Classes of applications that can benefit from such an infrastructure include traffic information, roadside businesses, weather reports, entertainment, and so on. There are several wireless communication methods currently available that can be utilized for vehicular applications, such as cellular phone networks, DSRC (dedicated short-range communication, and digital broadcasting. While a cellular phone network is relatively slow and a DSRC has a very small communication area, one-segment digital terrestrial broadcasting service was launched in Japan in 2006, high-performance digital broadcasting for mobile hosts has been available recently. However, broadcast delivery methods have the drawback that clients need to wait for the required data items to appear on the broadcast channel. In this paper, we propose a new cache system to effectively prefetch and replace broadcast data using “scope” (an available area of location-dependent data and “mobility specification” (a schedule according to the direction in which a mobile host moves. We numerically evaluate the cache system on the model close to the traffic road environment, and implement the emulation system to evaluate this location-aware data delivery method for a concrete vehicular application that delivers geographic road map data to a car navigation system.

  8. Vehicular Visible Light Networks for Urban Mobile Crowd Sensing.

    Science.gov (United States)

    Masini, Barbara M; Bazzi, Alessandro; Zanella, Alberto

    2018-04-12

    Crowd sensing is a powerful tool to map and predict interests and events. In the future, it could be boosted by an increasing number of connected vehicles sharing information and intentions. This will be made available by on board wireless connected devices able to continuously communicate with other vehicles and with the environment. Among the enabling technologies, visible light communication (VLC) represents a low cost solution in the short term. In spite of the fact that vehicular communications cannot rely on the sole VLC due to the limitation provided by the light which allows communications in visibility only, VLC can however be considered to complement other wireless communication technologies which could be overloaded in dense scenarios. In this paper we evaluate the performance of VLC connected vehicles when urban crowd sensing is addressed and we compare the performance of sole vehicular visible light networks with that of VLC as a complementary technology of IEEE 802.11p. Results, obtained through a realistic simulation tool taking into account both the roadmap constraints and the technologies protocols, help to understand when VLC provides the major improvement in terms of delivered data varying the number and position of RSUs and the FOV of the receiver.

  9. Plasma potential measurements in the edge region of the ISTTOK plasma, using electron emissive probes

    International Nuclear Information System (INIS)

    Ionita, C.; Balan, P.; Schrittwieser, R.; Cabral, J.A.; Fernandes, H.; Figueiredo, H. F.C.; Varandas, C.

    2001-01-01

    We have recently started to use electron-emissive probes for direct measurements of the plasma potential and its fluctuations in the edge region of the plasma ring in the tokamak ISTTOK in Lisbon, Portugal. This method is based on the fact that the electron emission current of such a probe is able to compensate electron temperature variations and electron drifts, which can occur in the edge plasma region of magnetized fusion devices, and which are making measurements with cold probes prone to errors. In this contribution we present some of the first results of our investigations in ISTTOK.(author)

  10. Transcutaneous measurement of the arterial input function in positron emission tomography

    International Nuclear Information System (INIS)

    Litton, J.E.; Eriksson, L.

    1990-01-01

    Positron emission tomography (PET) provides a powerful tool in medical research. Biochemical function can be both precisely localized and quantitatively measured. To achieve reliable quantitation it is necessary to know the time course of activity concentration in the arterial blood during the measurement. In this study the arterial blood curve from the brachial artery is compared to the activity measured in the internal carotid artery with a new transcutaneous detector

  11. Recent advances in measurement and dietary mitigation of enteric methane emissions in ruminants

    Directory of Open Access Journals (Sweden)

    Amlan Kumar Patra

    2016-05-01

    Full Text Available Methane (CH4 emission, which is mainly produced during normal fermentation of feeds by the rumen microorganisms, represents a major contributor to the greenhouse gas (GHG emissions. Several enteric CH4 mitigation technologies have been explored recently. A number of new techniques have also been developed and existing techniques have been improved in order to evaluate CH4 mitigation technologies and prepare an inventory of GHG emissions precisely. The aim of this review is to discuss different CH4 measuring and mitigation technologies, which have been recently developed. Respiration chamber technique is still considered as a gold standard technique due to its greater precision and reproducibility in CH4 measurements. With the adoption of recent recommendations for improving the technique, the SF6 method can be used with a high level of precision similar to the chamber technique. Short-term measurement techniques of CH4 measurements generally invite considerable within- and between animal variations. Among the short-term measuring techniques, Greenfeed and methane hood systems are likely more suitable for evaluation of CH4 mitigation studies, if measurements could be obtained at different times of the day relative to the diurnal cycle of the CH4 production. Carbon dioxide and CH4 ratio, sniffer and other short-term breath analysis techniques are more suitable for on farm screening of large number of animals to generate the data of low CH4 producing animals for genetic selection purposes. Different indirect measuring techniques are also investigated in recent years. Several new dietary CH4 mitigation technologies have been explored, but only a few of them are practical and cost-effective. Future research should be directed towards both the medium- and long-term mitigation strategies, which could be utilized on farms to accomplish substantial reductions of CH4 emissions and to profitably reduce carbon footprint of livestock production systems. This

  12. Recent Advances in Measurement and Dietary Mitigation of Enteric Methane Emissions in Ruminants.

    Science.gov (United States)

    Patra, Amlan K

    2016-01-01

    Methane (CH4) emission, which is mainly produced during normal fermentation of feeds by the rumen microorganisms, represents a major contributor to the greenhouse gas (GHG) emissions. Several enteric CH4 mitigation technologies have been explored recently. A number of new techniques have also been developed and existing techniques have been improved in order to evaluate CH4 mitigation technologies and prepare an inventory of GHG emissions precisely. The aim of this review is to discuss different CH4 measuring and mitigation technologies, which have been recently developed. Respiration chamber technique is still considered as a gold standard technique due to its greater precision and reproducibility in CH4 measurements. With the adoption of recent recommendations for improving the technique, the SF6 method can be used with a high level of precision similar to the chamber technique. Short-term measurement techniques of CH4 measurements generally invite considerable within- and between-animal variations. Among the short-term measuring techniques, Greenfeed and methane hood systems are likely more suitable for evaluation of CH4 mitigation studies, if measurements could be obtained at different times of the day relative to the diurnal cycle of the CH4 production. Carbon dioxide and CH4 ratio, sniffer, and other short-term breath analysis techniques are more suitable for on farm screening of large number of animals to generate the data of low CH4-producing animals for genetic selection purposes. Different indirect measuring techniques are also investigated in recent years. Several new dietary CH4 mitigation technologies have been explored, but only a few of them are practical and cost-effective. Future research should be directed toward both the medium- and long-term mitigation strategies, which could be utilized on farms to accomplish substantial reductions of CH4 emissions and to profitably reduce carbon footprint of livestock production systems. This review presents

  13. Measuring the coherence properties of light emission from laser-plasma interactions. Final report

    International Nuclear Information System (INIS)

    Batha, S.H.

    1998-01-01

    Several detrimental instabilities can be excited when a high-intensity laser interacts with plasma. The temporal evolution and spectra of the scattered light emitted by many of these instabilities are used to characterize the instabilities and to benchmark theories. It has been difficult to image the emission region with sufficient resolution to make quantitative comparisons with theory. Direct measurement of the emission region would yield information on ponderomotive steepening phenomena, the true emission zone of convective instabilities, and on the saturation of absolute instabilities. The increase in laser intensity caused by the filamentation instability is conjectured to elevate the levels of parametric instabilities found in high-energy laser-plasma interactions. Because the diameter of the filaments is very small (on the order of 10 microm), it is impossible to image the emission sites directly and either to prove or to disprove this conjecture. The research reported here examines an alternate method of measuring the emission region of scattered light from parametric instabilities. This report provides a brief background of coherence theory by defining the relevant parameters in Section 2. A concrete example of the effect that multiple scattering sites would have on the proposed measurement is provided in Section 3. The following section briefly describes experiments that might be able to demonstrate the proposed technique. The conclusion raises the issue of coherence and its effect on the expected angular distribution of scattering light from parametric instabilities

  14. Measurements of air pollution emission factors for marine transportation in SECA

    Directory of Open Access Journals (Sweden)

    B. Alföldy

    2013-07-01

    Full Text Available The chemical composition of the plumes of seagoing ships was measured during a two week long measurement campaign in the port of Rotterdam, Hoek van Holland The Netherlands, in September 2009. Altogether, 497 ships were monitored and a statistical evaluation of emission factors (g kg−1 fuel was provided. The concerned main atmospheric components were SO2, NO2, NOx and the aerosol particle number. In addition, the elemental and water-soluble ionic composition of the emitted particulate matter was determined. Emission factors were expressed as a function of ship type, power and crankshaft rotational speed. The average SO2 emission factor was found to be roughly half of what is allowed in sulphur emission control areas (16 vs. 30 g kg−1 fuel, and exceedances of this limit were rarely registered. A significant linear relationship was observed between the SO2 and particle number emission factors. The intercept of the regression line, 4.8 × 1015 (kg fuel−1, gives the average number of particles formed during the burning of 1 kg zero sulphur content fuel, while the slope, 2 × 1018, provides the average number of particles formed with 1 kg sulphur burnt with the fuel. Water-soluble ionic composition analysis of the aerosol samples from the plumes showed that ~144 g of particulate sulphate was emitted from 1 kg sulphur burnt with the fuel. The mass median diameter of sulphate particles estimated from the measurements was ~42 nm.

  15. Hydrocarbon emissions from gas engine CHP-units. 2011 measurement program

    Energy Technology Data Exchange (ETDEWEB)

    Van Dijk, G.H.J. [KEMA, Arnhem (Netherlands)

    2012-06-15

    In December 2009, the Ministry of Infrastructure and Environment (IandM) issued the Decree on Emission Limits for Middle Sized Combustion Installations (BEMS). This decree imposes a first-time emission limit value (ELV) of 1500 mg C/m{sup 3}{sub o} at 3% O{sub 2} for hydrocarbons emitted by gas engines. IandM used the findings of two hydrocarbon emission measurement programs, executed in 2007 and 2009, as a guideline for this initial ELV. The programs did reveal substantial variation in the hydrocarbon emissions of the gas engines tested. This variation, and especially the uncertainty as to the role of engine and/or other parameters causing such variation, was felt to hamper further policy development. IandM therefore commissioned KEMA to perform follow-up measurements on ten gas engine CHP-units in 2011. Aim of this 2011 program is to assess hydrocarbon emission variation in relation to engine parameters and process conditions including maintenance status, and to atmospheric conditions. The 2011 program comprised two identical measurement sessions, one in spring and one in winter.

  16. Spectral emissivity measurements of liquid refractory metals by spectrometers combined with an electrostatic levitator

    International Nuclear Information System (INIS)

    Ishikawa, Takehiko; Okada, Junpei T; Paradis, Paul-François; Ito, Yusuke; Masaki, Tadahiko; Watanabe, Yuki

    2012-01-01

    A spectral emissivity measurement system combined with an electrostatic levitator was developed for high-temperature melts. The radiation intensity from a high-temperature sample was measured with a multichannel photospectrometer (MCPD) over the 700–1000 nm spectral range, while a Fourier transform infrared spectrometer (FTIR) measured the radiation over the 1.1–6 µm interval. These spectrometers were calibrated with a blackbody radiation furnace, and the spectral hemispherical emissivity was calculated. The system's capability was evaluated with molten zirconium samples. The spectral hemispherical emissivity of molten zirconium showed a negative wavelength dependence and an almost constant variation over the 1850–2210 K temperature range. The total hemispherical emissivity of zirconium calculated by integrating the spectral hemispherical emissivity was found to be around 0.32, which showed good agreement with the literature values. The constant pressure heat capacity of molten zirconium at melting temperature was calculated to be 40.9 J mol −1 K −1 . (paper)

  17. Towards continuous global measurements and optimal emission estimates of NF3

    Science.gov (United States)

    Arnold, T.; Muhle, J.; Salameh, P.; Harth, C.; Ivy, D. J.; Weiss, R. F.

    2011-12-01

    We present an analytical method for the continuous in situ measurement of nitrogen trifluoride (NF3) - an anthropogenic gas with a global warming potential of ~16800 over a 100 year time horizon. NF3 is not included in national reporting emissions inventories under the United Nations Framework Convention on Climate Change (UNFCCC). However, it is a rapidly emerging greenhouse gas due to emission from a growing number of manufacturing facilities with increasing output and modern end-use applications, namely in microcircuit etching, and in production of flat panel displays and thin-film photovoltaic cells. Despite success in measuring the most volatile long lived halogenated species such as CF4, the Medusa preconcentration GC/MS system of Miller et al. (2008) is unable to detect NF3 under remote operation. Using altered techniques of gas separation and chromatography after initial preconcentration, we are now able to make continuous atmospheric measurements of NF3 with average precisions NF3 produced. Emission factors are shown to have reduced over the last decade; however, rising production and end-use have caused the average global atmospheric concentration to double between 2005 and 2011 i.e. half the atmospheric NF3 present today originates from emissions after 2005. Finally we show the first continuous in situ measurements from La Jolla, California, illustrating how global deployment of our technique could improve the temporal and spatial scale of NF3 'top-down' emission estimates over the coming years. These measurements will be important for independent verification of emissions should NF3 be regulated under a new climate treaty.

  18. Prescribed Grassland Burning Smoke Emission Measurements in the Northern Flint Hills Region

    Science.gov (United States)

    Wilkins, J. L.; Baker, K. R.; Landis, M.; Aurell, J.; Gullett, B.

    2017-12-01

    Historically, frequent wildfires were essential for the maintenance of native prairie fire adapted ecosystems. Today prescribed fires are used to control invasive woody species and potentially improve forage production in these same prairie ecosystems for the beef-cattle industry. The emission of primary particulate matter, secondary aerosol, ozone precursors, and air toxics from prescribed grassland burning operations has been implicated as drivers of downwind air quality problems across a multi-state area. A field study has been planned to quantify prescribed burn smoke emissions using both surface and aerial sampling platforms to better constrain emissions rates for organic and inorganic pollutants. Multiple prescribed burns on tallgrass prairie fields in the northern Flint Hills ecoregion are planned for March 2017 at the Konza Prairie Biological Station in Kansas. An array of measurement systems will be deployed to quantify a suite of continuous and integrated air pollution parameters, combustion conditions, meteorological parameters, and plume dynamics to calculate more accurate and condition-specific emission factors that will be used to better predict primary and secondary pollutants both locally and regionally. These emissions measurements will allow for evaluation and improvement of the U.S. Forest Service's Bluesky modeling framework which includes the Fire Emission Production Simulator (FEPS) and Fuel characterization classification system (FCCS). Elucidating grassland prescribed burning emission factors based on fuel type, loading, and environmental conditions is expected to provide an improved understanding of the impact of this land management practice on air quality in the greater Flint Hills region. It is also expected that measurements will be made to help constrain and develop better routines for fire plume rise, vertical allocation, and smoke optical properties.

  19. The case for refining bottom-up methane emission inventories using top-down measurements

    Science.gov (United States)

    Kelly, Bryce F. J.; Iverach, Charlotte P.; Ginty, Elisa; Bashir, Safdar; Lowry, Dave; Fisher, Rebecca E.; France, James L.; Nisbet, Euan G.

    2017-04-01

    Bottom-up global methane emission estimates are important for guiding policy development and mitigation strategies. Such inventories enable rapid and consistent proportioning of emissions by industrial sectors and land use at various scales from city to country to global. There has been limited use of top-down measurements to guide refining emission inventories. Here we compare the EDGAR gridmap data version 4.2 with over 5000 km of daytime ground level mobile atmospheric methane surveys in eastern Australia. The landscapes and industries surveyed include: urban environments, dryland farming, intensive livestock farming (both beef and lamb), irrigation agriculture, open cut and underground coal mining, and coal seam gas production. Daytime mobile methane surveys over a 2-year period show that at the landscape scale there is a high level of repeatability for the mole fraction of methane measured in the ground level atmosphere. Such consistency in the mole fraction of methane indicates that these data can be used as a proxy for flux. A scatter plot of the EDGAR emission gridmap Log[ton substance / 0.1 degree x 0.1 degree / year] versus the median mole fraction of methane / 0.1 degree x 0.1 degree in the ground level atmosphere highlights that the extent of elevated methane emissions associated with coal mining in the Hunter coalfields, which covers an area of 56 km by 24 km, has been under-represented in the EDGAR input data. Our results also show that methane emissions from country towns (population poor information on the extent of urban gas leaks. Given the uncertainties associated with the base land use and industry data for each country, we generalise the Australian observations to the global inventory with caution. The extensive comparison of top-down measurements versus the EDGAR version 4.2 methane gridmaps highlights the need for adjustments to the base resource data and/or the emission factors applied for coal mining, especially emissions from underground

  20. Space resolved measurements of neutrons and ion emission on plasma focus

    International Nuclear Information System (INIS)

    Jaeger, U.

    1980-05-01

    This report describes space-resolved measurements of neutrons and of accelerated charged particles, emitted by a plasmafocus-device. The neutron source has been measured with one and two-dimensional paraffin collimators. The space resolution is 5 mm along the axis and the radius, with a time resolution of 10 ns. In order to make quantitative statements about the neutron yield, neutron-scattering, absorption and nuclear reactions were taken into account. Part of the neutron measurements are carried out together with time and space resolved measurements of the electron density to study possible correlations between nsub(e) and Ysub(n). The following results about the neutron measurement were obtained: The neutron emission reaches its maximum between 40 and 60 ns after the maximum compression. The emission region is limited to a well defined range of 0 50 ns it has been observed a broadening of the emission region in + z-direction. The emission profiles in lower and in higher pressure regimes are almost the same. (orig./HT) [de

  1. Feasibility Analysis of Sustainability-Based Measures to Reduce VOC Emissions in Office Partition Manufacturing

    Directory of Open Access Journals (Sweden)

    Marc A. Rosen

    2010-02-01

    Full Text Available A feasibility analysis is reported of reduction opportunities for volatile organic compound (VOC emissions in manufacturing office furniture partitions, aimed at contributing to efforts to improve the sustainability of the process. A pollution prevention methodology is utilized. The purpose is to provide practical options for VOC emissions reductions during the manufacturing of office furniture partitions, but the concepts can be generally applied to the wood furniture industry. Baseline VOC emissions for a typical plant are estimated using a mass balance approach. The feasibility analysis expands on a preliminary screening to identify viable pollution prevention options using realistic criteria and weightings, and is based on technical, environmental and economic considerations. The measures deemed feasible include the implementation of several best management practices, ceasing the painting of non-visible parts, switching to hot melt backwrapping glue, application of solvent recycling and modification of the mechanical clip attachment. Implementation, measurement and control plans are discussed for the measures considered feasible, which can enhance the sustainability of the manufacturing of office furniture partitions. Reducing VOC emissions using the measures identified can, in conjunction with other measures, improve the sustainability of the manufacturing process.

  2. Measuring the Density of a Molecular Cluster Injector via Visible Emission from an Electron Beam

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, D. P.; Kaita, R.; Majeski, R. M.; Stotler, D. P.

    2010-06-28

    A method to measure the density distribution of a dense hydrogen gas jet is pre- sented. A Mach 5.5 nozzle is cooled to 80K to form a flow capable of molecular cluster formation. A 250V, 10mA electron beam collides with the jet and produces Hα emission that is viewed by a fast camera. The high density of the jet, several 1016cm-3, results in substantial electron depletion, which attenuates the Hα emission. The attenuated emission measurement, combined with a simplified electron-molecule collision model, allows us to determine the molecular density profile via a simple iterative calculation.

  3. Legislative measures for suppressing emission of nitrogen oxides from thermal power stations

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, V.R.

    1987-11-01

    Reviews measures taken by some countries to control emission of nitrogen oxides from thermal power stations run on solid fuels, mazout and gas. Refers to maximum permissible concentrations of nitrogen oxides in USA (100 mg/m/sup 3/), Canada (460 mg/m/sup 3/), Japan (41-62 mg/m/sup 3/) and several European countries. Discusses legislative measures in FRG (Federal Regulations BImSchG), particularly Instruction No. 13 BImSchV concerning large boilers run on solid fuels or mazout (continuous monitoring of nitrogen oxide emission into atmosphere, equipping old boilers with means of reducing nitrogen oxide emission, reduction of acid rain). Gives maximum permissible concentrations of nitrogen oxides for new boilers agreed by various countries. 5 refs.

  4. Multi-decadal satellite measurements of passive and eruptive volcanic SO2 emissions

    Science.gov (United States)

    Carn, Simon; Yang, Kai; Krotkov, Nickolay; Prata, Fred; Telling, Jennifer

    2015-04-01

    Periodic injections of sulfur gas species (SO2, H2S) into the stratosphere by volcanic eruptions are among the most important, and yet unpredictable, drivers of natural climate variability. However, passive (lower tropospheric) volcanic degassing is the major component of total volcanic emissions to the atmosphere on a time-averaged basis, but is poorly constrained, impacting estimates of global emissions of other volcanic gases (e.g., CO2). Stratospheric volcanic emissions are very well quantified by satellite remote sensing techniques, and we report ongoing efforts to catalog all significant volcanic SO2 emissions into the stratosphere and troposphere since 1978 using measurements from the ultraviolet (UV) Total Ozone Mapping Spectrometer (TOMS; 1978-2005), Ozone Monitoring Instrument (OMI; 2004 - present) and Ozone Mapping and Profiler Suite (OMPS; 2012 - present) instruments, supplemented by infrared (IR) data from HIRS, MODIS and AIRS. The database, intended for use as a volcanic forcing dataset in climate models, currently includes over 600 eruptions releasing a total of ~100 Tg SO2, with a mean eruption discharge of ~0.2 Tg SO2. Sensitivity to SO2 emissions from smaller eruptions greatly increased following the launch of OMI in 2004, but uncertainties remain on the volcanic flux of other sulfur species other than SO2 (H2S, OCS) due to difficulty of measurement. Although the post-Pinatubo 1991 era is often classified as volcanically quiescent, many smaller eruptions (Volcanic Explosivity Index [VEI] 3-4) since 2000 have injected significant amounts of SO2 into the upper troposphere - lower stratosphere (UTLS), peaking in 2008-2011. We also show how even smaller (VEI 2) tropical eruptions can impact the UTLS and sustain above-background stratospheric aerosol optical depth, thus playing a role in climate forcing on short timescales. To better quantify tropospheric volcanic degassing, we use ~10 years of operational SO2 measurements by OMI to identify the

  5. Effect of limiter recycling on measured poloidal impurity emission profiles in Tore Supra

    International Nuclear Information System (INIS)

    Hogan, J.; DeMichelis, C.; Monier-Garbet, P.; Becoulet, M.; Bush, C.; Ghendrih, P.; Guirlet, R.; Hess, W.; Mattioli, M.; Vallet, J.C.

    2001-01-01

    Poloidal impurity emission profiles measured with the Tore Supra grazing incidence duochromator exhibit a complex spatial structure during ergodic divertor operation with an outboard poloidal guard limiter. As previous measurements with inboard-wall limited plasmas have shown that these profiles give important information about the ergodic field structure, so the contribution of local neon recycling from the limiter-induced plume has been modeled. This permits a discrimination of edge and core transport effects. The BBQ 3D scrape-off layer code calculates the asymmetric contribution to the emission and MIST 1D simulation gives the symmetric part. A systematic increase is observed in the decay rate of neon emission after injection as the ergodic divertor strength is increased. The calculations permit identification of the limiter plume contribution to the profile structure, and, with this identification, the effect of the divertor to enhance impurity efflux can be seen from the decay data

  6. Measurement and communication of greenhouse gas emissions from U.S. food consumption via carbon calculators

    International Nuclear Information System (INIS)

    Kim, Brent; Neff, Roni

    2009-01-01

    Food consumption may account for upwards of 15% of U.S. per capita greenhouse gas emissions. Online carbon calculators can help consumers prioritize among dietary behaviors to minimize personal 'carbon footprints', leveraging against emissions-intensive industry practices. We reviewed the fitness of selected carbon calculators for measuring and communicating indirect GHG emissions from food consumption. Calculators were evaluated based on the scope of user behaviors accounted for, data sources, transparency of methods, consistency with prior data and effectiveness of communication. We found food consumption was under-represented (25%) among general environmental impact calculators (n = 83). We identified eight carbon calculators that accounted for food consumption and included U.S. users among the target audience. Among these, meat and dairy consumption was appropriately highlighted as the primary diet-related contributor to emissions. Opportunities exist to improve upon these tools, including: expanding the scope of behaviors included under calculations; improving communication, in part by emphasizing the ecological and public health co-benefits of less emissions-intensive diets; and adopting more robust, transparent methodologies, particularly where calculators produce questionable emissions estimates. Further, all calculators could benefit from more comprehensive data on the U.S. food system. These advancements may better equip these tools for effectively guiding audiences toward ecologically responsible dietary choices. (author)

  7. Methane emission from naturally ventilated livestock buildings can be determined from gas concentration measurements

    DEFF Research Database (Denmark)

    Bjerg, B; Zhang, Guoqiang; Madsen, J

    2012-01-01

    Determination of emission of contaminant gases as ammonia, methane, or laughing gas from natural ventilated livestock buildings with large opening is a challenge due to the large variations in gas concentration and air velocity in the openings. The close relation between calculated animal heat pr...... to investigate the influence of feed composition on methane emission in a relative large number of operating cattle buildings and consequently it can support a development towards reduced greenhouse gas emission from cattle production.......Determination of emission of contaminant gases as ammonia, methane, or laughing gas from natural ventilated livestock buildings with large opening is a challenge due to the large variations in gas concentration and air velocity in the openings. The close relation between calculated animal heat...... ventilated, 150 milking cow building. The results showed that the methane emission can be determined with much higher precision than ammonia or laughing gas emissions, and, for methane, relatively precise estimations can be based on measure periods as short as 3 h. This result makes it feasible...

  8. Real-time black carbon emission factor measurements from light duty vehicles.

    Science.gov (United States)

    Forestieri, Sara D; Collier, Sonya; Kuwayama, Toshihiro; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D

    2013-11-19

    Eight light-duty gasoline low emission vehicles (LEV I) were tested on a Chassis dynamometer using the California Unified Cycle (UC) at the Haagen-Smit vehicle test facility at the California Air Resources Board in El Monte, CA during September 2011. The UC includes a cold start phase followed by a hot stabilized running phase. In addition, a light-duty gasoline LEV vehicle and ultralow emission vehicle (ULEV), and a light-duty diesel passenger vehicle and gasoline direct injection (GDI) vehicle were tested on a constant velocity driving cycle. A variety of instruments with response times ≥0.1 Hz were used to characterize how the emissions of the major particulate matter components varied for the LEVs during a typical driving cycle. This study focuses primarily on emissions of black carbon (BC). These measurements allowed for the determination of BC emission factors throughout the driving cycle, providing insights into the temporal variability of BC emission factors during different phases of a typical driving cycle.

  9. Monitoring shipping emissions in the German Bight using MAX-DOAS measurements

    Science.gov (United States)

    Seyler, André; Wittrock, Folkard; Kattner, Lisa; Mathieu-Üffing, Barbara; Peters, Enno; Richter, Andreas; Schmolke, Stefan; Burrows, John P.

    2017-04-01

    Shipping is generally the most energy efficient transportation mode, but, at the same time, it accounts for four fifths of the worldwide total merchandise trade volume. As a result, shipping contributes a significant part to the emissions from the transportation sector. The majority of shipping emissions occurs within 400 km of land, impacting on air pollution in coastal areas and harbor towns. The North Sea has one of the highest ship densities in the world and the vast majority of ships heading for the port of Hamburg sail through the German Bight and into the river Elbe. A three-year time series of ground-based MAX-DOAS measurements of NO2 and SO2 on the island Neuwerk in the German Bight has been analyzed for contributions from shipping emissions. Measurements of individual ship plumes as well as of background pollution are possible from this location, which is 6-7 kilometers away from the main shipping lane towards the harbor of Hamburg. More than 2000 individual ship plumes have been identified in the data and analyzed for the emission ratio of SO2 to NO2, yielding an average ratio of 0.3 for the years 2013/2014. Contributions of ships and land-based sources to air pollution levels in the German Bight have been estimated, showing that despite the vicinity to the shipping lane, the contribution of shipping sources to air pollution is only about 40%. Since January 2015, much lower fuel sulfur content limits of 0.1% (before: 1.0%) apply in the North and Baltic Sea Emission Control Area (ECA). Comparing MAX-DOAS measurements from 2015/2016 (new regulation) to 2013/2014 (old regulation), a large reduction in SO2/NO2 ratios in shipping emissions and a significant reduction (by a factor of eight) in ambient coastal SO2 levels have been observed. In addition to that, selected shipping emission measurements from other measurement sites and campaigns are presented. This study is part of the project MeSMarT (Measurements of Shipping emissions in the Marine Troposphere

  10. Direct measurements of methane emissions from abandoned oil and gas wells in Pennsylvania.

    Science.gov (United States)

    Kang, Mary; Kanno, Cynthia M; Reid, Matthew C; Zhang, Xin; Mauzerall, Denise L; Celia, Michael A; Chen, Yuheng; Onstott, Tullis C

    2014-12-23

    Abandoned oil and gas wells provide a potential pathway for subsurface migration and emissions of methane and other fluids to the atmosphere. Little is known about methane fluxes from the millions of abandoned wells that exist in the United States. Here, we report direct measurements of methane fluxes from abandoned oil and gas wells in Pennsylvania, using static flux chambers. A total of 42 and 52 direct measurements were made at wells and at locations near the wells ("controls") in forested, wetland, grassland, and river areas in July, August, October 2013 and January 2014, respectively. The mean methane flow rates at these well locations were 0.27 kg/d/well, and the mean methane flow rate at the control locations was 4.5 × 10(-6) kg/d/location. Three out of the 19 measured wells were high emitters that had methane flow rates that were three orders of magnitude larger than the median flow rate of 1.3 × 10(-3) kg/d/well. Assuming the mean flow rate found here is representative of all abandoned wells in Pennsylvania, we scaled the methane emissions to be 4-7% of estimated total anthropogenic methane emissions in Pennsylvania. The presence of ethane, propane, and n-butane, along with the methane isotopic composition, indicate that the emitted methane is predominantly of thermogenic origin. These measurements show that methane emissions from abandoned oil and gas wells can be significant. The research required to quantify these emissions nationally should be undertaken so they can be accurately described and included in greenhouse gas emissions inventories.

  11. Characterization of emissions from a desktop 3D printer and indoor air measurements in office settings.

    Science.gov (United States)

    Steinle, Patrick

    2016-01-01

    Emissions from a desktop 3D printer based on fused deposition modeling (FDM) technology were measured in a test chamber and indoor air was monitored in office settings. Ultrafine aerosol (UFA) emissions were higher while printing a standard object with polylactic acid (PLA) than with acrylonitrile butadiene styrene (ABS) polymer (2.1 × 10(9) vs. 2.4 × 10(8) particles/min). Prolonged use of the printer led to higher emission rates (factor 2 with PLA and 4 with ABS, measured after seven months of occasional use). UFA consisted mainly of volatile droplets, and some small (100-300 nm diameter) iron containing and soot-like particles were found. Emissions of inhalable and respirable dust were below the limit of detection (LOD) when measured gravimetrically, and only slightly higher than background when measured with an aerosol spectrometer. Emissions of volatile organic compounds (VOC) were in the range of 10 µg/min. Styrene accounted for more than 50% of total VOC emitted when printing with ABS; for PLA, methyl methacrylate (MMA, 37% of TVOC) was detected as the predominant compound. Two polycyclic aromatic hydrocarbons (PAH), fluoranthene and pyrene, were observed in very low amounts. All other analyzed PAH, as well as inorganic gases and metal emissions except iron (Fe) and zinc (Zn), were below the LOD or did not differ from background without printing. A single 3D print (165 min) in a large, well-ventilated office did not significantly increase the UFA and VOC concentrations, whereas these were readily detectable in a small, unventilated room, with UFA concentrations increasing by 2,000 particles/cm(3) and MMA reaching a peak of 21 µg/m(3) and still being detectable in the room even 20 hr after printing.

  12. Nitrous Oxide (N2O) Emissions from California based on 2010 CalNex Airborne Measurements

    Science.gov (United States)

    Xiang, B.; Miller, S.; Kort, E. A.; Santoni, G. W.; Daube, B.; Commane, R.; Angevine, W. M.; Ryerson, T. B.; Trainer, M.; Andrews, A. E.; Nehrkorn, T.; Tian, H.; Wofsy, S. C.

    2012-12-01

    Nitrous oxide (N2O) is an important gas for climate and for stratospheric chemistry, with an atmospheric lifetime exceeding 100 years. Global concentrations have increased steadily since the 18th century, apparently due to human-associated emissions, principally from application of nitrogen fertilizers. However, quantitative studies of agricultural emissions at large spatial scales are lacking, inhibited by the difficulty of measuring small enhancements of atmospheric concentrations. Here we derive regional emission rates for N2O in the Central Valley of California, based on analysis of in-situ airborne atmospheric observations collected using a quantum cascade laser spectrometer. The data were obtained on board the NOAA P-3 research aircraft during the CalNex (California Research at the Nexus of Air Quality and Climate Change) program in May and June, 2010. We coupled WRF (Weather Research and Forecasting) model to STILT (Stochastic Time-Inverted Lagrangian Transport) to link our in-situ observations to surface emissions, and then used a variety of statistical methods to identify source areas and to extract optimized emission rates from the inversion. Our results support the view that fertilizer application is the largest source of N2O in the Central Valley. But the spatial distribution of derived surface emissions, based on California land use and activity maps, was very different than indicated in the leading emissions inventory (EDGAR 4.0), and our estimated total emission flux of N2O for California during the study period was 3 - 4 times larger than EDGAR and other inventories.

  13. Emissions of hydrogen cyanide from on-road gasoline and diesel vehicles

    Science.gov (United States)

    Moussa, Samar G.; Leithead, Amy; Li, Shao-Meng; Chan, Tak W.; Wentzell, Jeremy J. B.; Stroud, Craig; Zhang, Junhua; Lee, Patrick; Lu, Gang; Brook, Jeffery R.; Hayden, Katherine; Narayan, Julie; Liggio, John

    2016-04-01

    Hydrogen cyanide (HCN) is considered a marker for biomass burning emissions and is a component of vehicle exhaust. Despite its potential health impacts, vehicular HCN emissions estimates and their contribution to regional budgets are highly uncertain. In the current study, Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) was used to measure HCN emission factors from the exhaust of individual diesel, biodiesel and gasoline vehicles. Laboratory emissions data as a function of fuel type and driving mode were combined with ambient measurement data and model predictions. The results indicate that gasoline vehicles have the highest emissions of HCN (relative to diesel fuel) and that biodiesel fuel has the potential to significantly reduce HCN emissions even at realistic 5% blend levels. The data further demonstrate that gasoline direct injection (GDI) engines emit more HCN than their port fuel injection (PFI) counterparts, suggesting that the expected full transition of vehicle fleets to GDI will increase HCN emissions. Ambient measurements of HCN in a traffic dominated area of Toronto, Canada were strongly correlated to vehicle emission markers and consistent with regional air quality model predictions of ambient air HCN, indicating that vehicle emissions of HCN are the dominant source of exposure in urban areas. The results further indicate that additional work is required to quantify HCN emissions from the modern vehicle fleet, particularly in light of continuously changing engine, fuel and after-treatment technologies.

  14. Real time NO emissions measurement during cold start in LPG SI engine

    International Nuclear Information System (INIS)

    Li, Gong; Liu, Zhimin; Li, Zhilong; Qiu, Dongping; Li, Liguang

    2007-01-01

    To identify combustion occurrence is very important. Traditionally, cylinder pressure has been used as a criterion of combustion occurrence, but it can be unreliable when identifying lean mixture combustion (there is little difference in the cylinder pressure trace between the firing cycle and motoring cycles at the lean combustion limit). This is particularly important for fuels like LPG, which have a good capacity for lean combustion. In this study, a fast response NO detector, CambustionfNOx400, based on the chemiluminescence method, was used to measure real time NO emissions in order to evaluate the technique as a criterion for establishing combustion occurrence. At the same time, this paper presents an investigation of the characteristics of real time NO emissions of the first firing cycle during cold start in a LPG SI engine to determine the optimal excess air factor of the first firing cycle, and the cylinder pressure and crank shaft speed of the engine were measured and recorded. Test results show that the excess air ratio directly influences the cylinder pressure, engine speed and NO emissions of the first firing cycle. As the excess air coefficient is reduced from the lean misfiring limit, NO emissions increase quickly, then reduce quickly and then reduce slowly. NO emissions generally increase with peak cylinder pressure, even at constant excess air coefficient. Real time NO emissions can be used to identify cylinder combustion and misfire occurrence during engine cranking, even at the dilute combustion limit, and real time NO emission can be used to understand the combustion and misfire occurrence. (author)

  15. A comparative study of the enhancement of molecular emission in a spatially confined plume through optical emission spectroscopy and probe beam deflection measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Dayu; Liang, Peipei; Wu, Jiada; Xu, Ning; Ying, Zhifeng; Sun, Jian, E-mail: jsun@fudan.edu.cn

    2013-01-01

    The spatial confinement effects of shock wave on the expansion of a carbon plume induced by pulsed laser ablation of graphite in air and the enhancement of the plume emission were studied by optical emission spectroscopy and probe beam deflection measurements. A metal disk was set in the way of the ablation-generated shock wave to block and reflect the supersonically propagating shock wave. The reflected shock wave propagated backwards and confined the expanding plume. The optical emission of CN molecules was enhanced in contrast to the case without the block disk and the emission enhancement was dependent on the position of the disk. Based on the results of time-integrated and -resolved optical emission spectroscopy, and the time- and space-resolved probe beam deflection measurements, the processes occurring in the plume were discussed and the mechanisms responsible for the enhancement of molecular emission in the spatially confined plume were investigated. - Highlights: ► Spatial confinement and optical emission enhancement of carbon plume were studied. ► Ablation-generated shockwave propagating in air was reflected by a block disk. ► The effects of reflected shockwave on the emission enhancement were confirmed. ► The reflect shockwave confined the carbon plume and enhanced the plume emission.

  16. A comparative study of the enhancement of molecular emission in a spatially confined plume through optical emission spectroscopy and probe beam deflection measurements

    International Nuclear Information System (INIS)

    Ding, Dayu; Liang, Peipei; Wu, Jiada; Xu, Ning; Ying, Zhifeng; Sun, Jian

    2013-01-01

    The spatial confinement effects of shock wave on the expansion of a carbon plume induced by pulsed laser ablation of graphite in air and the enhancement of the plume emission were studied by optical emission spectroscopy and probe beam deflection measurements. A metal disk was set in the way of the ablation-generated shock wave to block and reflect the supersonically propagating shock wave. The reflected shock wave propagated backwards and confined the expanding plume. The optical emission of CN molecules was enhanced in contrast to the case without the block disk and the emission enhancement was dependent on the position of the disk. Based on the results of time-integrated and -resolved optical emission spectroscopy, and the time- and space-resolved probe beam deflection measurements, the processes occurring in the plume were discussed and the mechanisms responsible for the enhancement of molecular emission in the spatially confined plume were investigated. - Highlights: ► Spatial confinement and optical emission enhancement of carbon plume were studied. ► Ablation-generated shockwave propagating in air was reflected by a block disk. ► The effects of reflected shockwave on the emission enhancement were confirmed. ► The reflect shockwave confined the carbon plume and enhanced the plume emission

  17. Update of emission factors for nitrous oxide from agricultural soils on the basis of measurements in the Netherlands

    NARCIS (Netherlands)

    Kuikman, P.J.; Hoek, van der K.W.; Smit, A.; Zwart, K.B.

    2006-01-01

    Emissions of nitrous oxide (N2O) in the Netherlands are reported to the UNFCCC on the basis of a country specific methodology. In this study we have identified and analysed the values for emission factors in measurement from in the Netherlands in the period 1993 – 2003. The overall averaged emission

  18. 75 FR 68448 - Revisions to In-Use Testing for Heavy-Duty Diesel Engines and Vehicles; Emissions Measurement and...

    Science.gov (United States)

    2010-11-08

    ... later model year vehicles when operated under a wide range of real world driving conditions.\\1\\ The... diesel engines (through the Engine Manufacturers Association (EMA)) to develop ``data driven'' emission... Vehicles; Emissions Measurement and Instrumentation; Not-to-Exceed Emission Standards; and Technical...

  19. SphinX MEASUREMENTS OF THE 2009 SOLAR MINIMUM X-RAY EMISSION

    International Nuclear Information System (INIS)

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Bakała, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B.; Kuzin, S.; Farnik, F.; Reale, F.; Phillips, K. J. H.

    2012-01-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 × 10 47 cm –3 and 1.1 × 10 48 cm –3 . Comparing SphinX emission with that from the Hinode X-ray Telescope, we deduce that most of the emission is from general coronal structures rather than confined features like bright points. For one of 27 intervals of exceptionally low activity identified in the SphinX data, the Sun's X-ray luminosity in an energy range roughly extrapolated to that of ROSAT (0.1-2.4 keV) was less than most nearby K and M dwarfs.

  20. SphinX Measurements of the 2009 Solar Minimum X-Ray Emission

    Science.gov (United States)

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Kuzin, S.; Farnik, F.; Reale, F.; Phillips, K. J. H.; Bakała, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B.

    2012-06-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 × 1047 cm-3 and 1.1 × 1048 cm-3. Comparing SphinX emission with that from the Hinode X-ray Telescope, we deduce that most of the emission is from general coronal structures rather than confined features like bright points. For one of 27 intervals of exceptionally low activity identified in the SphinX data, the Sun's X-ray luminosity in an energy range roughly extrapolated to that of ROSAT (0.1-2.4 keV) was less than most nearby K and M dwarfs.

  1. SphinX MEASUREMENTS OF THE 2009 SOLAR MINIMUM X-RAY EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Sylwester, J.; Kowalinski, M.; Gburek, S.; Siarkowski, M.; Bakala, J.; Gryciuk, M.; Podgorski, P.; Sylwester, B. [Space Research Centre, Polish Academy of Sciences, 51-622, Kopernika 11, Wroclaw (Poland); Kuzin, S. [P. N. Lebedev Physical Institute (FIAN), Russian Academy of Sciences, Leninsky Prospect 53, Moscow 119991 (Russian Federation); Farnik, F. [Astronomical Institute, Ondrejov Observatory (Czech Republic); Reale, F. [Dipartimento di Fisica, Universita di Palermo, Palermo, Italy, and INAF, Osservatorio Astronomico di Palermo, Palermo (Italy); Phillips, K. J. H., E-mail: js@cbk.pan.wroc.pl [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)

    2012-06-01

    The SphinX X-ray spectrophotometer on the CORONAS-PHOTON spacecraft measured soft X-ray emission in the 1-15 keV energy range during the deep solar minimum of 2009 with a sensitivity much greater than GOES. Several intervals are identified when the X-ray flux was exceptionally low, and the flux and solar X-ray luminosity are estimated. Spectral fits to the emission at these times give temperatures of 1.7-1.9 MK and emission measures between 4 Multiplication-Sign 10{sup 47} cm{sup -3} and 1.1 Multiplication-Sign 10{sup 48} cm{sup -3}. Comparing SphinX emission with that from the Hinode X-ray Telescope, we deduce that most of the emission is from general coronal structures rather than confined features like bright points. For one of 27 intervals of exceptionally low activity identified in the SphinX data, the Sun's X-ray luminosity in an energy range roughly extrapolated to that of ROSAT (0.1-2.4 keV) was less than most nearby K and M dwarfs.

  2. Particle correlation based measurement of the mean time between the deuteron and proton emissions

    International Nuclear Information System (INIS)

    Ghisalberti, C.; Lebrun, C.; Sezac, L.; Ardouin, D.; Erazmus, B.; Eudes, P.; Ghuilbault, F.; Lautridou, P.; Rahmani, J.A.; Reposeur, T.; Chbihi, A.; Galin, J.; Guerreau, D.; Morjean, M.; Peghaire, A.; Lednicky, R.; Pluta, J.; Quebert, J.; Siemssen, R.

    1997-01-01

    Proton-deuteron correlations at small relative momenta have been measured with the reaction 208 Pb + 93 Nb at 29 MeV per nucleon at GANIL using the ORION neutron calorimeter. By selecting the proton-deuteron pairs according to the angle between their relative velocity and the pair center of mass velocity of the emitting source one can determine the average value of the time delay between the emission of these particles. The results reported in this paper for the first time at GANIL energies agree with the values published before in the literature i.e. 600 and 1500 fm/c for deuteron and proton emission times, respectively, as obtained in the reactions Ar + Ag at E/A = 17 MeV. At higher energies measurements with a B.U.U. calorimeter recording the collisions 14 N + 27 Al at E/A = 75 MeV show that in this case the proton emission begins at 15 fm/c and decreases slowly in time, while the deuterons are emitted at 50 fm/c and present a steep falling. This result agrees with a negative average value of d - t p >. Thus, the method presented in this report for determining the order of emission is of great interest for checking the theoretical description of the particle emission all the way in the collision dynamical process

  3. Assessment of the influence on vehicle emissions of driving style, vehicle technology and traffic measures

    NARCIS (Netherlands)

    Burgwal, H.C. van de; Gense, N.L.J.; Mierlo, J. van; Maggetto, G.

    2002-01-01

    The influence of traffic measures and driving style on different vehicle emissions and on primary energy consumption, and the definition of vehicle parameters influencing the relation between them, is an interesting issue to be assessed in order to allow more realistic estimations of the impact of

  4. Eddy flux and leaf level measurements of biogeni VOC emissions from Mopane woodland of Botswana

    NARCIS (Netherlands)

    Greenberg, J.P.; Guenter, A.; Harley, P.; Otter, L.; Veenendaal, E.M.; Hewwit, C.N.; James, A.E.; Owen, S.M.

    2003-01-01

    Biogenic volatile organic compound (BVOC) emissions were measured in a mopane woodland near Maun, Botswana in January–February 2001 as part of SAFARI 2000. This landscape is comprised of more than 95% of one woody plant species, Colophospermum mopane (Caesalpinaceae). Mopane woodlands extend over a

  5. Improved passive flux samplers for measuring ammonia emissions from animal houses, part 1: Basic principles

    NARCIS (Netherlands)

    Scholtens, R.; Hol, J.M.G.; Wagemans, M.J.M.; Phillips, V.R.

    2003-01-01

    At present, precise, expensive and laborious methods with a high resolution in time are needed, to determine ammonia emission rates from animal houses. The high costs for equipment, maintenance and labour limit the number of sites that can be measured. This study examines a new, simpler concept for

  6. Measurement of fluorescence emission spectrum of few strongly driven atoms using an optical nanofiber.

    Science.gov (United States)

    Das, Manoj; Shirasaki, A; Nayak, K P; Morinaga, M; Le Kien, Fam; Hakuta, K

    2010-08-02

    We show that the fluorescence emission spectrum of few atoms can be measured by using an optical nanofiber combined with the optical heterodyne and photon correlation spectroscopy. The observed fluorescence spectrum of the atoms near the nanofiber shows negligible effects of the atom-surface interaction and agrees well with the Mollow triplet spectrum of free-space atoms at high excitation intensity.

  7. Design of an Acoustic Probe to Measure Otoacoustic Emissions Below 0.5 kHz

    DEFF Research Database (Denmark)

    Christensen, Anders Tornvig; Ordoñez, Rodrigo; Hammershøi, Dorte

    2015-01-01

    Our ability to hear is reflected in low-level acoustic signals emitted from the ear. These otoacoustic emissions (OAEs) can be measured with an acoustic probe assembly coupling one or more small loudspeakers and microphones into the sealed ear canal. The electroacoustic instrumentation of commerc...

  8. Artifact rejection of distortion product otoacoustic emissions measured after sound exposure

    DEFF Research Database (Denmark)

    Reuter, Karen; Ordoñez, Rodrigo Pizarro; de Toro, Miguel Angel Aranda

    2007-01-01

    In a previous study [3] distortion product otoacoustic emissions (DPOAEs) were measured both before and after a moderate sound exposure, which caused a reduction of DPOAE levels. After the exposure DPOAEs had often levels below the noise floor. In the present paper it is discussed, whether...

  9. MEASUREMENT OF NITROGEN OXIDE EMISSIONS FROM AN AGRICULTURAL SOIL WITH A DYNAMIC CHAMBER SYSTEM

    Science.gov (United States)

    Biogenic soil emissions of nitric oxide (NO) were measured from an intensively managed agricultural row crop (corn, Zea mays) during a 4 week period May 15 through June 9, 1995). The site was located in Washington County, near the town of Plymouth, which is in the Lower Coastal P...

  10. Distortion-Product Otoacoustic Emission Measured Below 300 Hz in Normal-Hearing Human Subjects

    DEFF Research Database (Denmark)

    Christensen, Anders Tornvig; Ordoñez Pizarro, Rodrigo Eduardo; Hammershøi, Dorte

    2017-01-01

    , a custom-built low-frequency acoustic probe was put to use in 21 normal-hearing human subjects (of 34 recruited). Distortion-product otoacoustic emission (DPOAE) was measured in the enclosed ear canal volume as the response to two simultaneously presented tones with frequencies f1 and f2. The stimulus...

  11. Novel method for on-road emission factor measurements using a plume capture trailer.

    Science.gov (United States)

    Morawska, L; Ristovski, Z D; Johnson, G R; Jayaratne, E R; Mengersen, K

    2007-01-15

    The method outlined provides for emission factor measurements to be made for unmodified vehicles driving under real world conditions at minimal cost. The method consists of a plume capture trailer towed behind a test vehicle. The trailer collects a sample of the naturally diluted plume in a 200 L conductive bag and this is delivered immediately to a mobile laboratory for subsequent analysis of particulate and gaseous emissions. The method offers low test turnaround times with the potential to complete much larger numbers of emission factor measurements than have been possible using dynamometer testing. Samples can be collected at distances up to 3 m from the exhaust pipe allowing investigation of early dilution processes. Particle size distribution measurements, as well as particle number and mass emission factor measurements, based on naturally diluted plumes are presented. A dilution profile relating the plume dilution ratio to distance from the vehicle tail pipe for a diesel passenger vehicle is also presented. Such profiles are an essential input for new mechanistic roadway air quality models.

  12. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature

    NARCIS (Netherlands)

    Schmuck, S.; Fessey, J.; Gerbaud, T.; Alper, B.; Beurskens, M. N. A.; de la Luna, E.; Sirinelli, A.; Zerbini, M.

    2012-01-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron

  13. Optimal sensor locations for the backward Lagrangian stochastic technique in measuring lagoon gas emission

    Science.gov (United States)

    This study evaluated the impact of gas concentration and wind sensor locations on the accuracy of the backward Lagrangian stochastic inverse-dispersion technique (bLS) for measuring gas emission rates from a typical lagoon environment. Path-integrated concentrations (PICs) and 3-dimensional (3D) wi...

  14. Combustion and emission formation in a biomass fueled grate furnace - measurements and modelling

    International Nuclear Information System (INIS)

    Lindsjoe, H.

    1997-06-01

    A study of turbulent combustion with special emphasis on the formation of nitrous oxide emissions in a biomass fueled grate furnace has been conducted with the aid of measurements, literature studies and CFD-computations. The literature study covers nitrous oxide formation and the pyrolysis, gasification and combustion of biomass fuel. The measurements were conducted inside the furnace and at the outlet, and temperature and some major species were measured. A tool for the treatment of the bed processes (pyrolysis, gasification and combustion) has been developed. The measurements show significantly higher concentrations of oxygen above the fuel bed than expected. The gas production in the bed was shown to be very unevenly distributed over the width of the furnace. The measured temperatures were relatively low and in the same order as reported from other, similar measurements. The computational results are in good quantitative agreement with the measurements, even for the nitrous oxide emissions. It was necessary to include tar as one of the combustible species to achieve reasonable results. The computations point out that the fuel-NO mechanism is the most important reaction path for the formation of nitrous oxide in biomass combustion in grate furnaces. The thermal NO mechanism is responsible for less than 10% of the total amount of NO-emissions. Although the results are quantitatively in good agreement with the measurements, a sensitivity study showed that the fuel-NO model did not respond to changes in the distribution of secondary air as the measurements indicate. The results from this work have lead to some guidelines on how the furnace should be operated to achieve minimum NO-emissions. Some proposals of smaller changes in the construction are also given. 33 refs, 37 figs, 7 tabs

  15. Fluororeflectometer for measuring the emission, excitation, reflection and transmission of materials doped with active ions

    Energy Technology Data Exchange (ETDEWEB)

    Ramírez-Duverger, Aldo S., E-mail: aldo@cifus.uson.mx [Departamento de Física, Universidad de Sonora, Apdo. Postal 5-88, Hermosillo, Sonora 83000, México (Mexico); García-Llamas, Raúl, E-mail: ragal@cifus.uson.mx [Departamento de Investigación en Física, Universidad de Sonora, Apdo. Postal 5-88, Hermosillo, Sonora 83000, México (Mexico); Aceves, R., E-mail: raceves@cifus.uson.mx [Departamento de Investigación en Física, Universidad de Sonora, Apdo. Postal 5-88, Hermosillo, Sonora 83000, México (Mexico)

    2013-04-15

    The design and construction of a new hybrid instrument, which is named a fluororeflectometer, for measuring the radiation from materials doped with rare earth atoms is presented. This instrument operates in two modes. In the XL-λ mode, the instrument measures the luminescence and excitation spectra of the samples. In the RT-λ mode, the instrument measures the specular reflection and transmission spectra of thick or thin films. A photomultiplier (UV-enhanced photodiode) is used when the XL-λ (RT-λ) mode is in operation. The angle of incidence on the sample and the angle of the detected emission can be changed in both modes; the first one is changed manually and the last one is changed automatically. The reflection and transmission spectra from slabs of KCl:Eu{sup 2+} were measured to test the RT-λ mode. These data were fitted using Lorentz-type dispersion for the material, and the densities for each Eu absorption bands were obtained. In the XL-λ mode, the luminescence and excitation spectra from a slab and thin film of KCl:Eu{sup 2+} were obtained. The sensitivity of the instrument enables the luminescence from thin films with thicknesses as low as 3 μm to be measured; in this case, the signal barely exceeded the noise. The emission spectra from a slab of KCl:Eu{sup 2+} for several angles of incidence were measured in the direction parallel to the interfaces of the slab. -- Highlights: ► Develops an instrument for measuring optical properties of phosphors materials. ► Emission, excitation, transmission and reflectance are measured in KCl:Eu{sup 2+} slabs. ► The angular distribution for the emission, measured in situ, is also characterized. ► Its performance was compared with other instruments and good agreement is found. ► Capabilities are found superior to those offered by commercial fluorometers.

  16. Fluororeflectometer for measuring the emission, excitation, reflection and transmission of materials doped with active ions

    International Nuclear Information System (INIS)

    Ramírez-Duverger, Aldo S.; García-Llamas, Raúl; Aceves, R.

    2013-01-01

    The design and construction of a new hybrid instrument, which is named a fluororeflectometer, for measuring the radiation from materials doped with rare earth atoms is presented. This instrument operates in two modes. In the XL-λ mode, the instrument measures the luminescence and excitation spectra of the samples. In the RT-λ mode, the instrument measures the specular reflection and transmission spectra of thick or thin films. A photomultiplier (UV-enhanced photodiode) is used when the XL-λ (RT-λ) mode is in operation. The angle of incidence on the sample and the angle of the detected emission can be changed in both modes; the first one is changed manually and the last one is changed automatically. The reflection and transmission spectra from slabs of KCl:Eu 2+ were measured to test the RT-λ mode. These data were fitted using Lorentz-type dispersion for the material, and the densities for each Eu absorption bands were obtained. In the XL-λ mode, the luminescence and excitation spectra from a slab and thin film of KCl:Eu 2+ were obtained. The sensitivity of the instrument enables the luminescence from thin films with thicknesses as low as 3 μm to be measured; in this case, the signal barely exceeded the noise. The emission spectra from a slab of KCl:Eu 2+ for several angles of incidence were measured in the direction parallel to the interfaces of the slab. -- Highlights: ► Develops an instrument for measuring optical properties of phosphors materials. ► Emission, excitation, transmission and reflectance are measured in KCl:Eu 2+ slabs. ► The angular distribution for the emission, measured in situ, is also characterized. ► Its performance was compared with other instruments and good agreement is found. ► Capabilities are found superior to those offered by commercial fluorometers

  17. Accurate Measurements of Aircraft Engine Soot Emissions Using a CAPS PMssa Monitor

    Science.gov (United States)

    Onasch, Timothy; Thompson, Kevin; Renbaum-Wolff, Lindsay; Smallwood, Greg; Make-Lye, Richard; Freedman, Andrew

    2016-04-01

    We present results of aircraft engine soot emissions measurements during the VARIAnT2 campaign using CAPS PMssa monitors. VARIAnT2, an aircraft engine non-volatile particulate matter (nvPM) emissions field campaign, was focused on understanding the variability in nvPM mass measurements using different measurement techniques and accounting for possible nvPM sampling system losses. The CAPS PMssa monitor accurately measures both the optical extinction and scattering (and thus single scattering albedo and absorption) of an extracted sample using the same sample volume for both measurements with a time resolution of 1 second and sensitivity of better than 1 Mm-1. Absorption is obtained by subtracting the scattering signal from the total extinction. Given that the single scattering albedo of the particulates emitted from the aircraft engine measured at both 630 and 660 nm was on the order of 0.1, any inaccuracy in the scattering measurement has little impact on the accuracy of the ddetermined absorption coefficient. The absorption is converted into nvPM mass using a documented Mass Absorption Coefficient (MAC). Results of soot emission indices (mass soot emitted per mass of fuel consumed) for a turbojet engine as a function of engine power will be presented and compared to results obtained using an EC/OC monitor.

  18. Measuring the radial density distribution of light emission around the track of fast ions in nitrogen

    International Nuclear Information System (INIS)

    Ibach, T.

    1983-01-01

    For analysing the emission and stopping of ionization electrons (σ-electrons) emitted by fast ions passing through a gas, the radial density distribution of the light emission of the (0,0) transition of two optical bands in nitrogen have been measured. The systems selected for the epxeriments are the 2nd positive system (2.PS) at 337.1 nm primarily excited by low-energy electrons of about 20 eV, and the first negative system (1.NS) at 391.4 nm excited by faster electrons and simultaneous ionization. The equipment developed for the experiments records the light emission with a telescope-type optical arrangement including interference filters, allowing high local resolution and dynamics of the measured range. The measurements have been carried out at pressures between 0.133 and 13.3 mbar, using photons of energies ranging from 270 keV to 2.8 MeV, helium 3 beams of 270 keV/u and 500 keV/u, and neon beams of 270 keV/u. Abel's inversion applied to the distance functions allows calculation of the spatial light emission density which is normalized for a gas density of 1 g/cm 3 . The profiles of the two bands indicate that the σ-electron spectrum gets harder in outward direction. Next to the beam the impact density decreases faster with increasing ion energy than the stopping power (increasing interaction range of the σ-electrons). With photon beams, about half of the whole light emission in the 1. NS, and of the ionization, is induced by primary interactions of the ion beam. This proportion decreases at constant energy per nucleon with increasing atomic number of the ions as compared with the σ-electrons. The primary σ-emission gets harder with higher atomic numbers. (orig./HP) [de

  19. Road dust emissions from paved roads measured using different mobile systems.

    Science.gov (United States)

    Pirjola, Liisa; Johansson, Christer; Kupiainen, Kaarle; Stojiljkovic, Ana; Karlsson, Hans; Hussein, Tareq

    2010-12-01

    Very few real-world measurements of road dust suspension have been performed to date. This study compares two different techniques (referred to as Sniffer and Emma) to measure road dust emissions. The main differences between the systems are the construction of the inlet, different instruments for recording particulate matter (PM) levels, and different loads on the wheel axes (the weight of Sniffer was much higher than that of Emma). Both systems showed substantial small-scale variations of emission levels along the road, likely depending on-road surface conditions. The variations observed correlated quite well, and the discrepancies are likely a result of variations in dust load on the road surface perpendicular to the driving direction that cause variations in the measurements depending on slightly different paths driven by the two vehicles. Both systems showed a substantial influence on the emission levels depending on the type of tire used. The summer tire showed much lower suspension than the winter tires (one nonstudded and one studded). However, the relative importance of the nonstudded versus studded tire was rather different. For the ratio of studded/nonstudded, Emma shows higher values on all road sections compared with Sniffer. Both techniques showed increased emission levels with increasing vehicle speed. When the speed increased from 50 to 80 km hr(-1), the relative concentrations increased by 30-170% depending on the tire type and dust load. However, for road sections that were very dirty, Sniffer showed a much higher relative increase in the emission level with the nonstudded tire. Sniffer's absolute concentrations were mostly higher than Emma's. Possible reasons for the differences are discussed in the paper. Both systems can be used for studying relative road dust emissions and for designing air quality management strategies.

  20. Measurement of high-temperature spectral emissivity using integral blackbody approach

    Science.gov (United States)

    Pan, Yijie; Dong, Wei; Lin, Hong; Yuan, Zundong; Bloembergen, Pieter

    2016-11-01

    Spectral emissivity is one of the most critical thermophysical properties of a material for heat design and analysis. Especially in the traditional radiation thermometry, normal spectral emissivity is very important. We developed a prototype instrument based upon an integral blackbody method to measure material's spectral emissivity at elevated temperatures. An optimized commercial variable-high-temperature blackbody, a high speed linear actuator, a linear pyrometer, and an in-house designed synchronization circuit was used to implemented the system. A sample was placed in a crucible at the bottom of the blackbody furnace, by which the sample and the tube formed a simulated reference blackbody which had an effective total emissivity greater than 0.985. During the measurement, a pneumatic cylinder pushed a graphite rode and then the sample crucible to the cold opening within hundreds of microseconds. The linear pyrometer was used to monitor the brightness temperature of the sample surface, and the corresponding opto-converted voltage was fed and recorded by a digital multimeter. To evaluate the temperature drop of the sample along the pushing process, a physical model was proposed. The tube was discretized into several isothermal cylindrical rings, and the temperature of each ring was measurement. View factors between sample and rings were utilized. Then, the actual surface temperature of the sample at the end opening was obtained. Taking advantages of the above measured voltage signal and the calculated actual temperature, normal spectral emissivity under the that temperature point was obtained. Graphite sample at 1300°C was measured to prove the validity of the method.

  1. Measurement of Gross Alpha and Beta Emission Rates from Ceramic Tiles

    International Nuclear Information System (INIS)

    Wudthicharoonpun, Piyasak; Chankow, Nares

    2007-08-01

    Full text: Ceramic tiles normally used to cover floors and walls contain naturally occurring radioactive elements i.e. potassium-40, uranium, thorium and their daughters from raw materials. Thus, radioactivity was dependent upon source of raw materials and the amount used. The objective of this research was to measure gross alpha and beta emission rates to be used as a database for safety assessment and for selection of rooms to measure radioactive radon-222 gas

  2. Acoustic emission measurements on real reactor components with fracture mechanical interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Deuster, G

    1988-12-31

    This document presents acoustic emission measurements carried out on a reactor pressure vessel during different loadings: thermal shocking, hydro-test, cyclic loading. The acoustic emission system is described and results are provided. It appears that signals from crack border friction and crack propagation can be separated by the analysis of the signal parameters. During thermal shock, crack propagation can be detected very sensitively, together with crack border friction. During hydro-test, it appears that defects which do not grow during the experiment are not indicated, and no border friction appears. (TEC). 6 refs.

  3. Sportswear textiles emissivity measurement: comparison of IR thermography and emissometry techniques

    Science.gov (United States)

    Bison, P.; Grinzato, E.; Libbra, A.; Muscio, A.

    2012-06-01

    Three sportswear textiles are compared, one normal and two 'special' with Ag+ ions and Carbon powder added, with different colors. The emissivity of the textiles has been measured to determine if it is increased in the 'special' textiles with respect to the normal one. The test implied some non-standard procedure due to the semitransparent nature of the textiles, in comparison with the normal procedure that is commonly used on opaque surfaces. The test is also carried out by a standard emissometry technique, based on a comparative approach with reference samples having known thermal emissivity. The results are compared and discussed.

  4. Acoustic emission measurements on real reactor components with fracture mechanical interpretation

    International Nuclear Information System (INIS)

    Deuster, G.

    1988-01-01

    This document presents acoustic emission measurements carried out on a reactor pressure vessel during different loadings: thermal shocking, hydro-test, cyclic loading. The acoustic emission system is described and results are provided. It appears that signals from crack border friction and crack propagation can be separated by the analysis of the signal parameters. During thermal shock, crack propagation can be detected very sensitively, together with crack border friction. During hydro-test, it appears that defects which do not grow during the experiment are not indicated, and no border friction appears. (TEC)

  5. Multi-year remote-sensing measurements of gasoline light-duty vehicle emissions on a freeway ramp

    International Nuclear Information System (INIS)

    Sjoedin, A.; Andreasson, K.

    2000-01-01

    On-road optical remote-sensing measurements of gasoline light-duty vehicle (LDV) emissions - CO, HC, NO - were conducted on a freeway ramp in Gothenburg, Sweden, in 1991, 1995 and 1998. Based on almost 30,000 emission measurements, the results show that both catalyst cars and non-catalyst cars emissions deteriorate over time, but also that the emission performance of new TWC-cars has improved significantly in recent years. Furthermore, it was found that fleet age rather than model year determines the rate of emission deterioration for TWC-cars for both CO and NO. The study demonstrates that remote sensing may constitute a powerful tool to evaluate real-world LDV emissions; however, daily field calibration procedures need to be developed in order to assure that the evolution in fleet average emissions can be accurately measured. (author)

  6. Measurements and modeling to quantify emissions of methane and VOCs from shale gas operations: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Presto, Albert A [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-06-30

    The objectives of the project were to determine the leakage rates of methane and ozone-forming Volatile Organic Compounds (VOCs) and the emission rates of air toxics from Marcellus shale gas activities. Methane emissions in the Marcellus Shale region were differentiated between “newer” sources associated with shale gas development and “older” sources associated with coal or conventional natural gas exploration. This project conducted measurements of methane and VOC emissions from both shale and non-shale natural gas resources. The initial scope of the project was the Marcellus Shale basin, and measurements were conducted in both the western wet gas regions (southwest PA and WV) and eastern dry gas region (northeast PA) of the basin. During this project, we obtained additional funding from other agencies to expand the scope of measurements to include additional basins. The data from both the Marcellus and other basins were combined to construct a national analysis of methane emissions from oil & gas production activities.

  7. [Investigation of multi-wavelength effect during the measurement of UV-enhanced film's emission spectrum].

    Science.gov (United States)

    Liu, Meng; Ni, Zheng-ji; Zhang, Da-wei; Huang, Yuan-shen; Zhuang, Song-lin

    2009-09-01

    The UV-responsive detector is a dual-use device for civilian and military after the laser and IR-responsive sensors. Typical image sensor coated with a layer of down-convert frequency thin film on it's photosurface to enhance UV response is the key technology of enhancing UV-response. The UV-enhanced thin film was made in the experimental laboratory using the Zn2SiO4:Mn phosphor by spin coating method. Two peaks at 520 and 560 nm respectively in the emission spectrum of the UV-enhanced film were found by SP1702 spectrograph when the excitation wavelength was 260 and 280 nm. The peaks were found in the process of experiment of measuring and counting the quantum efficiency of UV-enhanced thin film. But the light peaks at 520 and 560 nm are not the emission light peaks by the exciting light of 260 and 280 nm. The reason why the light at 520 and 560 nm is not the emission light was analyzed based on the measurement principle of grating spectrograph. The reasons for the multi-wavelength of light overlaps during the measurement of emission spectrum were also discussed. And the equipment used to separate the overlapped different wavelengths was designed, which will be used to resolve the problem of the overlap of multi-wavelength.

  8. Development and testing of technical measures for the abatement of PM10 emissions from poultry housings

    Energy Technology Data Exchange (ETDEWEB)

    Ogink, N.W.M.; Aarnink, A.J.A.; Mosquera, J.; Winkel, A. [Wageningen UR Livestock Research, Wageningen (Netherlands)

    2010-07-01

    In order to comply with the European Union's ambient air quality standards, the Netherlands must reduce emissions of PM10. As a contributor to PM10, the poultry industry must implement mitigation measures before 2012. An extensive research and development program was launched in 2008 to provide abatement technology for broiler and layer houses. This paper presented results from studies carried out in 2008 and 2009 by Wageningen UR Livestock Research. The supply industry and poultry farmers participated in the study in which different methods and approaches were examined, including bedding material, light schedules, oil spraying systems, ionization systems, water scrubbers, combined scrubbers, electrostatic filters, and dry filters. Most methods were first tested and optimized in small units at an experimental poultry facility Lelystad. Several methods were validated in a next step on poultry farms, where PM10 emissions were measured to establish official emission factors. The oil spraying system and ionization system were tested in broiler houses and are nearing implementation. Reductions in PM10 emissions by different methods ranged from no effect to levels of 60 per cent. An outlook on adequate dust abatement measures for poultry housings was also provided.

  9. Airborne remote sensing and in situ measurements of atmospheric CO2 to quantify point source emissions

    Science.gov (United States)

    Krings, Thomas; Neininger, Bruno; Gerilowski, Konstantin; Krautwurst, Sven; Buchwitz, Michael; Burrows, John P.; Lindemann, Carsten; Ruhtz, Thomas; Schüttemeyer, Dirk; Bovensmann, Heinrich

    2018-02-01

    Reliable techniques to infer greenhouse gas emission rates from localised sources require accurate measurement and inversion approaches. In this study airborne remote sensing observations of CO2 by the MAMAP instrument and airborne in situ measurements are used to infer emission estimates of carbon dioxide released from a cluster of coal-fired power plants. The study area is complex due to sources being located in close proximity and overlapping associated carbon dioxide plumes. For the analysis of in situ data, a mass balance approach is described and applied, whereas for the remote sensing observations an inverse Gaussian plume model is used in addition to a mass balance technique. A comparison between methods shows that results for all methods agree within 10 % or better with uncertainties of 10 to 30 % for cases in which in situ measurements were made for the complete vertical plume extent. The computed emissions for individual power plants are in agreement with results derived from emission factors and energy production data for the time of the overflight.

  10. Homotopic non-local regularized reconstruction from sparse positron emission tomography measurements

    International Nuclear Information System (INIS)

    Wong, Alexander; Liu, Chenyi; Wang, Xiao Yu; Fieguth, Paul; Bie, Hongxia

    2015-01-01

    Positron emission tomography scanners collect measurements of a patient’s in vivo radiotracer distribution. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (tracer), which is introduced into the body on a biologically active molecule, and the tomograms must be reconstructed from projections. The reconstruction of tomograms from the acquired PET data is an inverse problem that requires regularization. The use of tightly packed discrete detector rings, although improves signal-to-noise ratio, are often associated with high costs of positron emission tomography systems. Thus a sparse reconstruction, which would be capable of overcoming the noise effect while allowing for a reduced number of detectors, would have a great deal to offer. In this study, we introduce and investigate the potential of a homotopic non-local regularization reconstruction framework for effectively reconstructing positron emission tomograms from such sparse measurements. Results obtained using the proposed approach are compared with traditional filtered back-projection as well as expectation maximization reconstruction with total variation regularization. A new reconstruction method was developed for the purpose of improving the quality of positron emission tomography reconstruction from sparse measurements. We illustrate that promising reconstruction performance can be achieved for the proposed approach even at low sampling fractions, which allows for the use of significantly fewer detectors and have the potential to reduce scanner costs

  11. Gaussian model for emission rate measurement of heated plumes using hyperspectral data

    Science.gov (United States)

    Grauer, Samuel J.; Conrad, Bradley M.; Miguel, Rodrigo B.; Daun, Kyle J.

    2018-02-01

    This paper presents a novel model for measuring the emission rate of a heated gas plume using hyperspectral data from an FTIR imaging spectrometer. The radiative transfer equation (RTE) is used to relate the spectral intensity of a pixel to presumed Gaussian distributions of volume fraction and temperature within the plume, along a line-of-sight that corresponds to the pixel, whereas previous techniques exclusively presume uniform distributions for these parameters. Estimates of volume fraction and temperature are converted to a column density by integrating the local molecular density along each path. Image correlation velocimetry is then employed on raw spectral intensity images to estimate the volume-weighted normal velocity at each pixel. Finally, integrating the product of velocity and column density along a control surface yields an estimate of the instantaneous emission rate. For validation, emission rate estimates were derived from synthetic hyperspectral images of a heated methane plume, generated using data from a large-eddy simulation. Calculating the RTE with Gaussian distributions of volume fraction and temperature, instead of uniform distributions, improved the accuracy of column density measurement by 14%. Moreover, the mean methane emission rate measured using our approach was within 4% of the ground truth. These results support the use of Gaussian distributions of thermodynamic properties in calculation of the RTE for optical gas diagnostics.

  12. Methane Emission By Grazing Livestock. A Synopsis Of 1000 Direct Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lassey, K.R. [National Institute of Water and Atmospheric Research (NIWA), Wellington (New Zealand); Ulyatt, M.J. [New Zealand Pastoral Agriculture Research Institute (AgResearch), Palmerston North (New Zealand)

    2000-07-01

    In a series of field campaigns since 1995, a team of atmospheric and ruminant-nutrition scientists have measured methane emissions directly from individual ruminant livestock freely grazing representative New Zealand pastures. The technique collects integrated 'breath' samples during grazing, using an implanted SF6 source as a conservative calibrated tracer, an approach pioneered by Johnson et al. [1994]. Most of these measurements have been on grazing sheep (942 animal-days to Aug 1999), others on grazing dairy cows (283), with some measurements also on sheep under controlled feeding conditions (305) [eg, Lassey et al., 1997; Ulyatt et al., 1999]. The aim is to characterise the variability of emission rates, including their dependence on pasture quality and physiological condition. The research goal is two-fold: (1) to provide a better scientific basis for assessing the national emissions inventory; and (2) to investigate options for mitigating livestock emissions. Here, we discuss the research strategy and overview the principal research findings. We note in particular, that as a source of enterically fermented methane, sheep may not be merely 'small cattle'. 5 refs.

  13. Impact of hydrogen insertion on vehicular natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Strangueto, Karina Maretti; Silva, Ennio Peres da [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. of Mechanical Engineering. Energy Dept.], Email: karinakms@fem.unicamp.br

    2010-07-01

    This article aims to analyze the possibility of insertion of hydrogen in the vehicular natural gas or even the insertion of the hydrogen in the compressed natural gas used in Brazil. For the production of this hydrogen, the spilled turbinable energy from Itaipu would be harnessed. The calculation of production can be extended to other power plants which are close to the natural gas pipelines, where the hydrogen would be introduced. Then, it was analyzed the consumption of natural gas in vehicles in Brazil, the regulation of transportation, the sales of compressed natural gas to fuelling station, the specifications that the piped gas should follow to be sold, and how much hydrogen could be accepted in the mix. (author)

  14. Multiagent Based Information Dissemination in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    S.S. Manvi

    2009-01-01

    Full Text Available Vehicular Ad hoc Networks (VANETs are a compelling application of ad hoc networks, because of the potential to access specific context information (e.g. traffic conditions, service updates, route planning and deliver multimedia services (Voice over IP, in-car entertainment, instant messaging, etc.. This paper proposes an agent based information dissemination model for VANETs. A two-tier agent architecture is employed comprising of the following: 1 'lightweight', network-facing, mobile agents; 2 'heavyweight', application-facing, norm-aware agents. The limitations of VANETs lead us to consider a hybrid wireless network architecture that includes Wireless LAN/Cellular and ad hoc networking for analyzing the proposed model. The proposed model provides flexibility, adaptability and maintainability for traffic information dissemination in VANETs as well as supports robust and agile network management. The proposed model has been simulated in various network scenarios to evaluate the effectiveness of the approach.

  15. Vehicular traffic noise prediction using soft computing approach.

    Science.gov (United States)

    Singh, Daljeet; Nigam, S P; Agrawal, V P; Kumar, Maneek

    2016-12-01

    A new approach for the development of vehicular traffic noise prediction models is presented. Four different soft computing methods, namely, Generalized Linear Model, Decision Trees, Random Forests and Neural Networks, have been used to develop models to predict the hourly equivalent continuous sound pressure level, Leq, at different locations in the Patiala city in India. The input variables include the traffic volume per hour, percentage of heavy vehicles and average speed of vehicles. The performance of the four models is compared on the basis of performance criteria of coefficient of determination, mean square error and accuracy. 10-fold cross validation is done to check the stability of the Random Forest model, which gave the best results. A t-test is performed to check the fit of the model with the field data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Intelligent transportation systems dependable vehicular communications for improved road safety

    CERN Document Server

    Ferreira, Joaquim; Fonseca, José

    2016-01-01

    This book presents cutting-edge work on the most challenging research issues concerning intelligent transportation systems (ITS), introducing selected, highly relevant advanced research on scheduling and real-time communication for vehicular networks, as well as fault tolerance, test beds and simulations for ITS. The authors define new architectures that support cooperative sensing in ITS and offer guidance for the development of a reference end-to-end implementation. The presented results allow advanced traffic and travel management strategies to be formulated on the basis of reliable and real-time input data. The effectiveness of these new strategies, together with the proposed systems, is assessed in field trials and via simulations. The chapters in this book detail new research findings, algorithms, protocols, and the development of an implementation platform for ITS that merges and integrates heterogeneous data sources into a common system. In addition, they provide a set of advanced tools for the contro...

  17. Spectrally resolved pressure dependence measurements of air fluorescence emission with AIRFLY

    International Nuclear Information System (INIS)

    Ave, M.; Bohacova, M.; Buonomo, B.; Busca, N.; Cazon, L.; Chemerisov, S.D.; Conde, M.E.; Crowell, R.A.; Di Carlo, P.; Di Giulio, C.; Doubrava, M.; Esposito, A.; Facal, P.; Franchini, F.J.; Hoerandel, J.; Hrabovsky, M.; Iarlori, M.; Kasprzyk, T.E.; Keilhauer, B.; Klages, H.

    2008-01-01

    The knowledge of the fluorescence emission as a function of atmospheric parameters is essential for the detection of extensive air showers with the fluorescence technique. In this paper, we summarize AIRFLY published measurements of the pressure dependence of the fluorescence yield. The spectral distribution of the fluorescent light between 280 and 429 nm has been measured with high resolution. Relative intensities of 34 spectral lines have been determined. The pressure dependence of 25 lines was measured in terms of quenching reference pressures p λ ' in air. This set of AIRFLY measurements yields the most comprehensive parametrization of the pressure dependence of the fluorescent spectrum.

  18. Methods for measuring the emission of dust in the air from the industrial objects

    International Nuclear Information System (INIS)

    Petsovska-Gjorgjevich, M.

    2006-01-01

    Two methods are used for measuring the emission of dust in the air from the industrial objects. The first is gravimetrical method, measuring of particular matter in flowing gases, using GRAVIMAT SHC 502 sampler, and the second is optoelectronic method working with the transmission light principle with extinction output, using OMD 41 in-situ dust monitor. Both methods are explained theoretically and the probe measurement is fulfilled for one of our industrial objects. The two methods are connected, because of the necessity of the implementation of the results from the first measurements in the second ones which are continual for long time. (Author)

  19. Land Surface Microwave Emissivities Derived from AMSR-E and MODIS Measurements with Advanced Quality Control

    Science.gov (United States)

    Moncet, Jean-Luc; Liang, Pan; Galantowicz, John F.; Lipton, Alan E.; Uymin, Gennady; Prigent, Catherine; Grassotti, Christopher

    2011-01-01

    A microwave emissivity database has been developed with data from the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and with ancillary land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the same Aqua spacecraft. The primary intended application of the database is to provide surface emissivity constraints in atmospheric and surface property retrieval or assimilation. An additional application is to serve as a dynamic indicator of land surface properties relevant to climate change monitoring. The precision of the emissivity data is estimated to be significantly better than in prior databases from other sensors due to the precise collocation with high-quality MODIS LST data and due to the quality control features of our data analysis system. The accuracy of the emissivities in deserts and semi-arid regions is enhanced by applying, in those regions, a version of the emissivity retrieval algorithm that accounts for the penetration of microwave radiation through dry soil with diurnally varying vertical temperature gradients. These results suggest that this penetration effect is more widespread and more significant to interpretation of passive microwave measurements than had been previously established. Emissivity coverage in areas where persistent cloudiness interferes with the availability of MODIS LST data is achieved using a classification-based method to spread emissivity data from less-cloudy areas that have similar microwave surface properties. Evaluations and analyses of the emissivity products over homogeneous snow-free areas are presented, including application to retrieval of soil temperature profiles. Spatial inhomogeneities are the largest in the vicinity of large water bodies due to the large water/land emissivity contrast and give rise to large apparent temporal variability in the retrieved emissivities when satellite footprint locations vary over time. This issue will be dealt with in the future by

  20. Greenhouse gas emissions during MSW landfilling in China: influence of waste characteristics and LFG treatment measures.

    Science.gov (United States)

    Yang, Na; Zhang, Hua; Shao, Li-Ming; Lü, Fan; He, Pin-Jing

    2013-11-15

    Reducing greenhouse gas (GHG) emissions from municipal solid waste (MSW) treatment can be highly cost-effective in terms of GHG mitigation. This study investigated GHG emissions during MSW landfilling in China under four existing scenarios and in terms of seven different categories: waste collection and transportation, landfill management, leachate treatment, fugitive CH4 (FM) emissions, substitution of electricity production, carbon sequestration and N2O and CO emissions. GHG emissions from simple sanitary landfilling technology where no landfill gas (LFG) extraction took place (Scenario 1) were higher (641-998 kg CO2-eq·t(-1)ww) than those from open dump (Scenario 0, 480-734 kg CO2-eq·t(-1)ww). This was due to the strictly anaerobic conditions in Scenario 1. LFG collection and treatment reduced GHG emissions to 448-684 kg CO2-eq·t(-1)ww in Scenario 2 (with LFG flare) and 214-277 kg CO2-eq·t(-1)ww in Scenario 3 (using LFG for electricity production). Amongst the seven categories, FM was the predominant contributor to GHG emissions. Global sensitivity analysis demonstrated that the parameters associated with waste characteristics (i.e. CH4 potential and carbon sequestered faction) and LFG management (i.e. LFG collection efficiency and CH4 oxidation efficiency) were of great importance. A further learning on the MSW in China indicated that water content and dry matter content of food waste were the basic factors affecting GHG emissions. Source separation of food waste, as well as increasing the incineration ratio of mixed collected MSW, could effectively mitigate the overall GHG emissions from landfilling in a specific city. To increase the LFG collection and CH4 oxidation efficiencies could considerably reduce GHG emissions on the landfill site level. While, the improvement in the LFG utilization measures had an insignificant impact as long as the LFG is recovered for energy generation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. The first full-resolution measurements of Auroral Medium Frequency Burst Emissions

    Science.gov (United States)

    Bunch, N. L.; Labelle, J.; Weatherwax, A.; Hughes, J.

    2008-12-01

    Auroral MF burst is a naturally occurring auroral radio emission which appears unstructured on resolution of previous measurements, is observed in the frequency range of 0.8-4.5 MHz, and has typical amplitudes of around 10-14 V2/m2Hz, and durations of a few minutes. The emission occurs at substorm onset. Since Sept 2006, Dartmouth has operated a broadband (0-5 MHz) interferometer at Toolik Lake, Alaska (68° 38' N, 149° 36' W, 68.51 deg. magnetic latitude), designed for the study of auroral MF burst emissions. Normal operation involves taking snapshots of waveforms from four spaced antennas from which wave spectral and directional information is obtained. However, the experiment can also be run in "continuous mode" whereby the signal from a selected antenna is sampled continuously at 10 M samples/second. A "continuous mode" campaign was run 0800-1200 UT (~2200-0200 MLT) daily from March 21 to April 19, 2008. During this campaign more than twenty auroral MF burst emissions were observed, including three extraordinarily intense examples lasting approximately two minutes each. These observations represent the highest time and frequency resolution data ever collected of MF burst emissions. These data allow us to better characterize the null near twice the electron gyrofrequency identified in previous experiments, since examples of this feature observed during this campaign display a strong null ~50 kHz in bandwidth, with sharp boundaries and occasionally coincident with 2 fce auroral roar. These data also allow us to search for frequency-time structures embedded in MF-burst. One prominent feature appears to be a strong single frequency emission which broadens down to lower frequencies over time, spreading to approximately 500 kHz in bandwidth over ~10 ms. Among other features observed are a diffuse and unstructured emission, as well as what could potentially be several separate emission sources, with multiple emissions occurring simultaneously, appearing as weaker

  2. A model to relate wind tunnel measurements to open field odorant emissions from liquid area sources

    Science.gov (United States)

    Lucernoni, F.; Capelli, L.; Busini, V.; Sironi, S.

    2017-05-01

    Waste Water Treatment Plants are known to have significant emissions of several pollutants and odorants causing nuisance to the near-living population. One of the purposes of the present work is to study a suitable model to evaluate odour emissions from liquid passive area sources. First, the models describing volatilization under a forced convection regime inside a wind tunnel device, which is the sampling device that typically used for sampling on liquid area sources, were investigated. In order to relate the fluid dynamic conditions inside the hood to the open field and inside the hood a thorough study of the models capable of describing the volatilization phenomena of the odorous compounds from liquid pools was performed and several different models were evaluated for the open field emission. By means of experimental tests involving pure liquid acetone and pure liquid butanone, it was verified that the model more suitable to describe precisely the volatilization inside the sampling hood is the model for the emission from a single flat plate in forced convection and laminar regime, with a fluid dynamic boundary layer fully developed and a mass transfer boundary layer not fully developed. The proportionality coefficient for the model was re-evaluated in order to account for the specific characteristics of the adopted wind tunnel device, and then the model was related with the selected model for the open field thereby computing the wind speed at 10 m that would cause the same emission that is estimated from the wind tunnel measurement furthermore, the field of application of the proposed model was clearly defined for the considered models during the project, discussing the two different kinds of compounds commonly found in emissive liquid pools or liquid spills, i.e. gas phase controlled and liquid phase controlled compounds. Lastly, a discussion is presented comparing the presented approach for emission rates recalculation in the field, with other approaches

  3. The application of acoustic emission measurements on laboratory testpieces to large scale pressure vessel monitoring

    International Nuclear Information System (INIS)

    Ingham, T.; Dawson, D.G.

    1975-01-01

    A test pressure vessel containing 4 artificial defects was monitored for emission whilst pressure cycling to failure. Testpieces cut from both the failed vessel and from as-rolled plate material were tested in the laboratory. A marked difference in emission characteristics was observed between plate and vessel testpieces. Activity from vessel material was virtually constant after general yield and emission amplitudes were low. Plate testpieces showed maximum activity at general yield and more frequent high amplitude emissions. An attempt has been made to compare the system sensitivities between the pressure vessel test and laboratory tests. In the absence of an absolute calibration device, system sensitivities were estimated using dummy signals generated by the excitation of an emission sensor. The measurements have shown an overall difference in sensitivity between vessel and laboratory tests of approximately 25db. The reduced sensitivity in the vessel test is attributed to a combination of differences in sensors, acoustic couplant, attenuation, and dispersion relative to laboratory tests and the relative significance of these factors is discussed. Signal amplitude analysis of the emissions monitored from laboratory testpieces showed that, whith losses of the order of 25 to 30db, few emissions would be detected from the pressure vessel test. It is concluded that no reliable prediction of acoustic behaviour of a structure may be made from laboratory test unless testpieces of the actual structural material are used. A considerable improvement in detection sensitivity, is also required for reliable detection of defects in low strength ductile materials and an absolute method of system calibration is required between tests

  4. EXPERIMENTAL MEASUREMENT, ANALYSIS AND MODELLING OF DEPENDENCY EMISSIVITY IN FUNCTION OF TEMPERATURE

    Directory of Open Access Journals (Sweden)

    N. Baba Ahmed

    2015-08-01

    Full Text Available We propose a direct method of measurement of the total emissivity of opaque samples on a range of temperature around the ambient one. The method rests on the modulation of the temperature of the sample and the infra-red signal processing resulting from the surface of the sample we model the total emissivity obtained in experiments according to the temperature to establish linear correlations. This leads us to apply the method of optimal linearization associated the finite element method with the nonlinear problem of transfer of heat if thermal conductivity, the specific heat and the emissivity of studied material depend on the temperature. We obtain a good agreement between the resolution of the nonlinear equation of heat and the results obtained by the experimentation. .

  5. LERFCM: a computer code for spatial reconstruction of volume emission from chord measurements in plasmas

    International Nuclear Information System (INIS)

    Navarro, A.P.; Pare, V.K.; Dunlap, J.L.

    1981-01-01

    Local Emissivity Reconstruction from Chord Measurements (LERFCM) is a package of computer programs used to determine the two-dimensional spatial distribution of the emission intensity of radiation in a plasma from line integral data, which represents signals from arrays of collimated detectors looking through the plasma along different chords in a plane. The method requires data from only a few detector arrays and assumes that the emission distribution in the plane of observation has a smooth angular dependence that can be represented by a few low-order harmonics. The intended application is a reconstruction of plasma shape and MHD instabilities, using data from arrays of soft x-ray detectors on Impurity Study Experiment Tokamak

  6. Eddy covariance measurements and parameterisation of traffic related particle emissions in an urban environment

    Directory of Open Access Journals (Sweden)

    E. M. Mårtensson

    2006-01-01

    Full Text Available Urban aerosol sources are important due to the health effects of particles and their potential impact on climate. Our aim has been to quantify and parameterise the urban aerosol source number flux F (particles m−2 s−1, in order to help improve how this source is represented in air quality and climate models. We applied an aerosol eddy covariance flux system 118.0 m above the city of Stockholm. This allowed us to measure the aerosol number flux for particles with diameters >11 nm. Upward source fluxes dominated completely over deposition fluxes in the collected dataset. Therefore, the measured fluxes were regarded as a good approximation of the aerosol surface sources. Upward fluxes were parameterised using a traffic activity (TA database, which is based on traffic intensity measurements. The footprint (area on the surface from which sources and sinks affect flux measurements, located at one point in space of the eddy system covered road and building construction areas, forests and residential areas, as well as roads with high traffic density and smaller streets. We found pronounced diurnal cycles in the particle flux data, which were well correlated with the diurnal cycles in traffic activities, strongly supporting the conclusion that the major part of the aerosol fluxes was due to traffic emissions. The emission factor for the fleet mix in the measurement area EFfm=1.4±0.1×1014 veh−1 km−1 was deduced. This agrees fairly well with other studies, although this study has an advantage of representing the actual effective emission from a mixed vehicle fleet. Emission from other sources, not traffic related, account for a F0=15±18×106 m−2 s−1. The urban aerosol source flux can then be written as F=EFfmTA+F0. In a second attempt to find a parameterisation, the friction velocity U* normalised with the average friction velocity has been included, F=EF . This parameterisation results in a somewhat reduced emission factor, 1.3×1014 veh

  7. On the capability of IASI measurements to inform about CO surface emissions

    Directory of Open Access Journals (Sweden)

    S. Szopa

    2009-11-01

    Full Text Available Between July and November 2008, simultaneous observations were conducted by several orbiting instruments that monitor carbon monoxide in the atmosphere, among them the Infrared Atmospheric Sounding Instrument (IASI and Measurements Of Pollution In The Troposphere (MOPITT. In this paper, the concentration retrievals at about 700 hPa from these two instruments are successively used in a variational Bayesian system to infer the global distribution of CO emissions. Starting from a global emission budget of 479 Tg for the considered period, the posterior estimate of CO emissions using IASI retrievals gives a total of 643 Tg, which is in close agreement with the budget calculated with version 3 of the MOPITT data (649 Tg. The regional totals are also broadly consistent between the two inversions. Even though our theoretical error budget indicates that IASI constrains the emissions slightly less than MOPITT, because of lesser sensitivity in the lower troposphere, these first results indicate that IASI may play a major role in the quantification of the emissions of CO.

  8. On-board emission measurement of high-loaded light-duty vehicles in Algeria.

    Science.gov (United States)

    Boughedaoui, Ménouèr; Kerbachi, Rabah; Joumard, Robert

    2008-01-01

    A sample of eight private gasoline and diesel conventional light-duty vehicles (LDVs) in use with various ages, carrying a load of 460 kg, were tested on a representative trip in the traffic flow of the city of Blida to obtain emission factors representing the actual use conditions of Algerian LDVs. The gas sampling system (mini-constant volume sampling) as well as the analyzers are carried on-board the vehicle. Around 55 tests were conducted during 3 months covering more than 480 km under various real driving conditions. The mean speed downtown is about 16.1 km/hr with a rather low acceleration, an average of 0.60 m/sec2. For each test, kinematics are recorded as well as the analysis of the four emitted pollutants carbon dioxide, carbon monoxide, oxides of nitrogen, and total hydrocarbons. Emission factors were evaluated according to speed for each category of gasoline and diesel engines. The influence of some parameters such as cold/hot start, age of vehicle and its state of maintenance are discussed. Results are compared with the European database ARTEMIS for comparable vehicles. These measurements contribute to the development of unit emission of the vehicles used in Algeria, which are necessary for the calculation of emission inventory of pollutants and greenhouse gases from the road transportation sector. The unit emissions constitute a tool of decisionmaking aid regarding the conception of new regulations of vehicle control and inspection in Algeria and even in similar developing countries.

  9. Isoprene emission rates and fluxes measured above a Mediterranean oak ( Quercus pubescens) forest

    Science.gov (United States)

    Simon, V.; Dumergues, L.; Bouchou, P.; Torres, L.; Lopez, A.

    2005-03-01

    The present work, carried out as part of the European fiEld experimentS to COnstrain Models of atmospheric Pollution and Transport of Emissions project (ESCOMPTE), brings a new contribution to the inventory of the main natural hydrocarbons sources that are liable to participate in the production of ozone. The measurement campaign was conducted in Montmeyan, a site close to Marseilles (France), with the aim of quantifying the terpenic emission pattern and the behaviour of Quercus pubescens, an important Mediterranean tree species. Biogenic emissions by Q. pubescens were determined by the enclosure of an intact branch of this tree in a Teflon cuvette. The total monoterpenic emission rates thus recorded were found to reach maximum values ranged between 40 and 350 μg g Dry Weight-1 h -1. Emissions were correlated strongly with leaf temperature and Photosynthetic Active Radiation (PAR). The fluxes were also determined by extrapolating the results of the enclosure method and by using aerodynamic gradient method. They reach around 73 mg m -2 h -1 with the first method and 55 mg m -2 h -1 with the second one. The obtained values fit with a maximal ratio of 2.

  10. Real-time measurement of electron beam weld penetration in uranium by acoustic emission monitoring

    International Nuclear Information System (INIS)

    Whittaker, J.W.; Murphy, J.L.

    1991-07-01

    High quality electron beam (EB) welds are required in uranium test articles. Acoustic emission (AE) techniques are under development with the goal of measuring weld penetration in real-time. One technique, based on Average Signal Level (ASL) measurement was used to record weld AE signatures. Characteristic AE signatures were recorded for bead-on-plate (BOP) and butt joint (BJ) welds made under varied welding conditions. AE waveforms were sampled to determine what microscopic AE behavior led to the observed macroscopic signature features. Deformation twinning and weld expulsion are two of the main sources of emission. AE behavior was correlated with weld penetration as measured by standard metallographic techniques. The ASL value was found to increase approximately linearly with weld penetration in BJ welds. These results form the basis for a real-time monitoring technique for weld penetration. 5 refs

  11. Radially localized measurements of superthermal electrons using oblique electron cyclotron emission

    International Nuclear Information System (INIS)

    Preische, S.; Efthimion, P.C.; Kaye, S.M.

    1996-05-01

    It is shown that radial localization of optically tin Electron Cyclotron Emission from superthermal electrons can be imposed by observation of emission upshifted from the thermal cyclotron resonance in the horizontal midplane of a tokamak. A new and unique diagnostic has been proposed and operated to make radially localized measurements of superthermal electrons during Lower Hybrid Current Drive on the PBX-M tokamak. The superthermal electron density profile as well as moments of the electron energy distribution as a function of radius are measured during Lower Hybrid Current Drive. The time evolution of these measurements after the Lower Hybrid power is turned off are given and the observed behavior reflects the collisional isotropization of the energy distribution and radial diffusion of the spatial profile

  12. Temperature gradient scale length measurement: A high accuracy application of electron cyclotron emission without calibration

    Energy Technology Data Exchange (ETDEWEB)

    Houshmandyar, S., E-mail: houshmandyar@austin.utexas.edu; Phillips, P. E.; Rowan, W. L. [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States); Yang, Z. J. [Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Hubbard, A. E.; Rice, J. E.; Hughes, J. W.; Wolfe, S. M. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02129 (United States)

    2016-11-15

    Calibration is a crucial procedure in electron temperature (T{sub e}) inference from a typical electron cyclotron emission (ECE) diagnostic on tokamaks. Although the calibration provides an important multiplying factor for an individual ECE channel, the parameter ΔT{sub e}/T{sub e} is independent of any calibration. Since an ECE channel measures the cyclotron emission for a particular flux surface, a non-perturbing change in toroidal magnetic field changes the view of that channel. Hence the calibration-free parameter is a measure of T{sub e} gradient. B{sub T}-jog technique is presented here which employs the parameter and the raw ECE signals for direct measurement of electron temperature gradient scale length.

  13. Effect of different fertilization measures on soil CO2 emissions of spring corn in Northeast China

    Science.gov (United States)

    Xu, Shicai; Qiao, Shaoqing

    2018-04-01

    To research the sustainability of efficient utilization approaches and modes of nitrogen in spring corns. Taking different fertilization measures to research the influence on soil respiration and microbial biomass carbon and nitrogen; the experiment takes the spring corns and black soil of Harbin in Northeast China as research objects. It researches the influence of 4 different fertilization measures by using field long-term located experiment on soil respiration of the spring corns and analyzes the yield. The four measures are as follows: farmer's fertilization practice FP; Tl mode of decreasing 20% of nitrogenous fertilizer on the basis of FP; T2 mode of 20% of Tl nitrogenous fertilizer replaced by organic fertilizer and other 20% replaced by slow-release nitrogen fertilizer; T3 mode of adding 2t/hm2 of corn stalk carbon on the basis of T2. There are significant differences of CO2 emission flux in spring corn soil with four fertilization measures (PTl>T2>FP and the yield rank of spring corns is: T3>T2>Tl>FP. (1) The rational nitrogen-decrease fertilization measure has no obvious influence on spring corn yield and the replacement of organic fertilizer and slow-release nitrogen fertilizer and the addition of active carbon can improve the spring corn yield. (2) Utilization of organic fertilizer can accelerate the emission of CO2 from the soil. (3) Addition of biological carbon can promote the emission of CO2 from soil during the growing period of spring corns.

  14. Highly-controlled, reproducible measurements of aerosol emissions from African biomass combustion

    Science.gov (United States)

    Haslett, Sophie; Thomas, J. Chris; Morgan, William; Hadden, Rory; Liu, Dantong; Allan, James; Williams, Paul; Sekou, Keïta; Liousse, Catherine; Coe, Hugh

    2017-04-01

    Particulate emissions from biomass burning can alter the atmosphere's radiative balance and cause significant harm to human health. However, the relationship between these emissions and fundamental combustion processes is, to date, poorly characterised. In atmospheric models, aerosol emissions are represented by emission factors based on mass loss, which are averaged over an entire combustion event for each particulate species. This approach, however, masks huge variability in emissions during different phases of the combustion period. Laboratory tests have shown that even small changes to the burning environment can lead to huge variation in observed aerosol emission factors (Akagi et al., 2011). In order to address this gap in understanding, in this study, small wood samples sourced from Côte D'Ivoire were burned in a highly-controlled laboratory environment. The shape and mass of samples, available airflow and surrounding heat were carefully regulated. Organic aerosol and refractory black carbon emissions were measured in real-time using an Aerosol Mass Spectrometer and a Single Particle Soot Photometer, respectively. Both of these instruments are used regularly to measure aerosol concentrations in the field. This methodology produced remarkably repeatable results, allowing three different phases of combustion to be identified by their emissions. Black carbon was emitted predominantly during flaming combustion; organic aerosols were emitted during pyrolysis before ignition and from smouldering-dominated behaviour near the end of combustion. During the flaming period, there was a strong correlation between the emission of black carbon and the rate of mass loss, which suggests there is value in employing a mass-based emission factor for this species. However, very little correlation was seen between organic aerosol and mass loss throughout the tests. As such, results here suggest that emission factors averaged over an entire combustion event are unlikely to be

  15. Environmental Management Department Quality Assurance Project Plan for Radionuclide Emission Measurements Project for compliance with National Emission Standards for Hazardous Air Pollutants (NESHAP)

    Energy Technology Data Exchange (ETDEWEB)

    Poole, D A

    1992-06-01

    This Quality Assurance Project Plan (QAPP) satisfies the quality assurance (QA) requirements in 40 CFR Part 61, Method 114, for ensuring that the radionuclide air emission measurements from the Y-12 Plant are representative; of a known precision and accuracy; and include administrative controls to ensure prompt response when emission measurements indicate an increase over normal radionuclide emissions. The QAPP ensures the quality of the Y-12 Plant radionuclide emission measurements data from the continuous samplers, breakthrough monitors, and minor radionuclide release points. The plan specifies the procedures for the management of the activities affecting the quality of the data for the Y-12 Plant Environmental Management Department (EMD) within the Health, Safety, Environment, and Accountability Division (HSEA).

  16. Environmental Management Department Quality Assurance Project Plan for Radionuclide Emission Measurements Project for compliance with National Emission Standards for Hazardous Air Pollutants (NESHAP)

    International Nuclear Information System (INIS)

    Poole, D.A.

    1992-06-01

    This Quality Assurance Project Plan (QAPP) satisfies the quality assurance (QA) requirements in 40 CFR Part 61, Method 114, for ensuring that the radionuclide air emission measurements from the Y-12 Plant are representative; of a known precision and accuracy; and include administrative controls to ensure prompt response when emission measurements indicate an increase over normal radionuclide emissions. The QAPP ensures the quality of the Y-12 Plant radionuclide emission measurements data from the continuous samplers, breakthrough monitors, and minor radionuclide release points. The plan specifies the procedures for the management of the activities affecting the quality of the data for the Y-12 Plant Environmental Management Department (EMD) within the Health, Safety, Environment, and Accountability Division (HSEA)

  17. PM, NOx and butane emissions from on-road vehicle fleets in Hong Kong and their implications on emission control policy

    Science.gov (United States)

    Ning, Zhi; Wubulihairen, Maimaitireyimu; Yang, Fenhuan

    2012-12-01

    Vehicular emissions are the major sources of air pollution in urban areas. For metropolitan cities with large population working and living in environments with direct traffic impact, emission control is of great significance to protect public health. Implementation of more stringent emission standards, retrofitting fleet with emission control devices and switching to clearer fuel has been commonly practiced in different cities including Hong Kong. The present study employed a new plume chasing method for effective and quick evaluation of on-road fleet emission factors of particulate matter (PM), nitrogen oxides (NOx), and butane from heavy duty diesel trucks, diesel buses and liquefied petroleum gas (LPG) vehicles. The results showed distinct profiles of the emissions from different fleets with excessive butane emissions from LPG fleet and contrasting PM and NOx emissions from diesel trucks and buses fleets. A cross comparison was also made with emission data from other cities and from historic local studies. The implications of the observed difference on the effectiveness of emission control measures and policy are discussed with recommendations of direction for future research and policy making.

  18. Contribution to design a communication framework for vehicular ad hoc networks in urban scenarios

    OpenAIRE

    Tripp Barba, Carolina

    2013-01-01

    The constant mobility of people, the growing need to be always connected, the large number of vehicles that nowadays can be found in the roads and the advances in technology make Vehicular Ad hoc Networks (VANETs) be a major area of research. Vehicular Ad hoc Networks are a special type of wireless Mobile Ad hoc Networks (MANETs), which allow a group of mobile nodes configure a temporary network and maintain it without the need of a fixed infrastructure. A vehicular network presents some spec...

  19. A study on the impact of parameter uncertainty on the emission-based ranking of transportation projects.

    Science.gov (United States)

    2014-01-01

    With the growing concern with air quality levels and, hence, the livability of urban regions in the nation, it has become increasingly common to incorporate vehicular emission considerations in the ranking of transportation projects. Network assignme...

  20. Measurement of ethylene emission from Japanese red pine (Pinus densiflora) under field conditions in NOx-polluted areas

    International Nuclear Information System (INIS)

    Kume, A.; Nakatani, N.; Tsuboi, N.; Nakane, K.; Sakurai, N.; Nakagawa, N.; Sakugawa, H.

    2001-01-01

    Emission of ethylene from the needles of Japanese red pine, Pinus densiflora, was measured in air-polluted areas in Hiroshima, Japan. We applied a suitable protocol to determine the rate of ethylene emission from the excised needles. The influence of excision of needles on ethylene emission was not detected during the first 4 h of incubation at 20degC. Ethylene emissions were low in the unpolluted (Clean) areas regardless of the altitude or season. The emission of stress ethylene increased with the atmospheric NO 2 concentration, suggesting that atmospheric NO x or related substances induced the higher ethylene emission in the polluted areas (near urban and industrial areas). In all cases, 1-year-old needles emitted significantly larger amounts of ethylene than the current needles. Ethylene emission did not increase evenly in the polluted areas, but the frequency of trees emitting high ethylene increased. Therefore, threshold rates for the baseline ethylene emission were proposed. (Author)

  1. Air/Superfund National Technical Guidance Study Series. Data Base of emission-rate-measurement projects. Technical note

    Energy Technology Data Exchange (ETDEWEB)

    Eklund, B.; Petrinec, C.; Ranum, D.; Howlett, L.

    1991-06-01

    A compilation and evaluation of Volatile Organic Compound (VOC) emission rate data was performed. The three primary objectives were (1) to determine typical averages and ranges of emissions for various types of sources; (2) to determine the degree of correlation between emission rate results from different sampling methods; and (3) to examine the effects of different variables on measured emission rates. Emission rate data are presented for 33 studies covering 13 types of emission sources. The sources include landfills, surface impoundments, waste water treatment systems, leaking underground storage tanks, soil piles and landfarms. The emission rate data were obtained by using the Emission Isolation Flux Chamber, Downhole Emissions Isolation Flux Chamber, the Concentration Profile method and the Transect method. For each source, the total non-methane hydrocarbon and benzene emission rates are reported along with three other compounds that had the highest emission rate. Source concentration data (e.g. concentration in soil or waste water) are also reported for comparison to the measured emission rates.

  2. Vehicle-specific emissions modeling based upon on-road measurements.

    Science.gov (United States)

    Frey, H Christopher; Zhang, Kaishan; Rouphail, Nagui M

    2010-05-01

    Vehicle-specific microscale fuel use and emissions rate models are developed based upon real-world hot-stabilized tailpipe measurements made using a portable emissions measurement system. Consecutive averaging periods of one to three multiples of the response time are used to compare two semiempirical physically based modeling schemes. One scheme is based on internally observable variables (IOVs), such as engine speed and manifold absolute pressure, while the other is based on externally observable variables (EOVs), such as speed, acceleration, and road grade. For NO, HC, and CO emission rates, the average R(2) ranged from 0.41 to 0.66 for the former and from 0.17 to 0.30 for the latter. The EOV models have R(2) for CO(2) of 0.43 to 0.79 versus 0.99 for the IOV models. The models are sensitive to episodic events in driving cycles such as high acceleration. Intervehicle and fleet average modeling approaches are compared; the former account for microscale variations that might be useful for some types of assessments. EOV-based models have practical value for traffic management or simulation applications since IOVs usually are not available or not used for emission estimation.

  3. Isoprene emissions at the canopy scale: measurements in the Escompte program

    Science.gov (United States)

    Serça, D.; Fotiadi, A.; Bouchou, P.; Cortinovis, J.

    2003-04-01

    Concentrations of biogenic volatile organic compounds (BVOCs) play a crucial role in the atmospheric chemistry through their role in the production-destruction cycle of tropospheric O3. Half of these BVOCs would be made of isoprene (C5H8), a compound predominantly emitted by ligneous species. Measurements presented here were collected during the ESCOMPTE campaign carried out in the Marseille region, South-West of France. Meteorological parameters, microclimate and fluxes were measured at the canopy scale of a Quercus pubescens forest. Latent and sensible heat, CO2 and isoprene fluxes were calculated using the eddy covariance method. Isoprene fluxes followed the expected diurnal evolution, with maximum emissions at noon reaching about 5 to 10 mgC m-2 h-1. Significant regression coefficient (r2 between 0.61 and 0.76) were found between isoprene emission and PAR, isoprene concentrations and energy fluxes (latent and sensible). The strongest correlation (r2 = 0.8) was found between mean emission and temperature averaged each day between 6 am and 6pm. A cumulative effect of temperature was observed with a constant flux increase (max from 5 to 15 mgCm-2h-1) along a one week period corresponding to an increase in maximum temperature from 24°C to 30°C. The calculated mean emission factor (37.2 µg g-1dw h-1) is in the order of values found in the literature for oak Mediterranean forests.

  4. Measurements of Parameters Controlling the Emissions of Organophosphate Flame Retardants in Indoor Environments.

    Science.gov (United States)

    Liang, Yirui; Liu, Xiaoyu; Allen, Matthew R

    2018-05-15

    Emission of semivolatile organic compounds (SVOCs) from source materials usually occurs very slowly in indoor environments due to their low volatility. When the SVOC emission process is controlled by external mass transfer, the gas-phase concentration in equilibrium with the material ( y 0 ) is used as a key parameter to simplify the source models that are based on solid-phase diffusion. A material-air-material (M-A-M) configured microchamber method was developed to rapidly measure y 0 for a polyisocyanurate rigid foam material containing organophosphate flame retardants (OPRFs). The emission test was conducted in 44 mL microchambers for target OPFRs, including tris(2-chloroethyl) phosphate (CASRN: 115-96-8), tris(1-chloro-2-propyl) phosphate (CASRN: 13674-84-5), and tris(1,3-dichloro-2-propyl) phosphate (CASRN: 13674-87-8). In addition to the microchamber emission test, two other types of tests were conducted to determine y 0 for the same foam material: OPFR diffusive tube sampling tests from the OPFR source foam using stainless-steel thermal desorption tubes and sorption tests of OPFR on an OPFR-free foam in a 53 L small chamber. Comparison of parameters obtained from the three methods suggests that the discrepancy could be caused by a combination of theoretical, experimental, and computational differences. Based on the y 0 measurements, a linear relationship between the ratio of y 0 to saturated vapor pressure concentration and material-phase mass fractions has been found for phthalates and OPFRs.

  5. Emissions of volatile organic compounds inferred from airborne flux measurements over a megacity

    Directory of Open Access Journals (Sweden)

    T. Karl

    2009-01-01

    Full Text Available Toluene and benzene are used for assessing the ability to measure disjunct eddy covariance (DEC fluxes of Volatile Organic Compounds (VOC using Proton Transfer Reaction Mass Spectrometry (PTR-MS on aircraft. Statistically significant correlation between vertical wind speed and mixing ratios suggests that airborne VOC eddy covariance (EC flux measurements using PTR-MS are feasible. City-median midday toluene and benzene fluxes are calculated to be on the order of 14.1±4.0 mg/m2/h and 4.7±2.3 mg/m2/h, respectively. For comparison the adjusted CAM2004 emission inventory estimates toluene fluxes of 10 mg/m2/h along the footprint of the flight-track. Wavelet analysis of instantaneous toluene and benzene measurements during city overpasses is tested as a tool to assess surface emission heterogeneity. High toluene to benzene flux ratios above an industrial district (e.g. 10–15 g/g including the International airport (e.g. 3–5 g/g and a mean flux (concentration ratio of 3.2±0.5 g/g (3.9±0.3 g/g across Mexico City indicate that evaporative fuel and industrial emissions play an important role for the prevalence of aromatic compounds. Based on a tracer model, which was constrained by BTEX (BTEX– Benzene/Toluene/Ethylbenzene/m, p, o-Xylenes compound concentration ratios, the fuel marker methyl-tertiary-butyl-ether (MTBE and the biomass burning marker acetonitrile (CH3CN, we show that a combination of industrial, evaporative fuel, and exhaust emissions account for >87% of all BTEX sources. Our observations suggest that biomass burning emissions play a minor role for the abundance of BTEX compounds in the MCMA (2–13%.

  6. Oil palm and the emission of greenhouse gasses- from field measurements in Indonesia

    Science.gov (United States)

    Rahman, Niharika; Bruun, Thilde Bech; Giller, Ken E.; Magid, Jakob; van de Ven, Gerrie; de Neergaard, Andreas

    2017-04-01

    Palm oil from the oil palm (Elaeis guianensis) has in recent years become the world's most important vegetable oil. The increasing demand for palm oil has led to expansion of oil palm plantations, which has caused environmental controversies associated with carbon losses and the use of large amounts of mineral fertilizers. Efforts to increase sustainability of oil palm cultivation, include recycling of oil-mill residues and pruning's, but with this comes increased potential for methane emission from the plantations. Until now no field-based data on greenhouse gas emissions from oil palm plantations have been reported. Here for the first time we present data from a long term (360 days) field trial in Bah Lias Research Station, North Sumatra, Indonesia on greenhouse gas emissions from an oil palm plantation with various treatments of recycled oil palm waste products, fertilizers and simulated rainfall. The first experiment was conducted over a full year (dry + wet season) with mineral fertilizer treatments including urea and ammonium sulphate, and organic fertilizer treatments constituting: empty fruit bunches (EFB), enriched mulch (EFB + palm oil mill effluent (POME) ) and pruned oil palm fronds (OPF). Treatment doses represent the current management in Indonesian plantations and the higher doses that are expected in the imminent future. For the organic treatments several methods of application (applied in inter-rows, piles, patches or bands) were evaluated. The second experiment investigated effects of soil water saturation on GHG emissions through adding 25 mm simulated rainfall per day for 21 days. Each palm tree received 1 kg of N fertilizer as urea or ammonium sulphate and enriched mulch. The gas fluxes in the fields was measured by a large static-chamber (1.8 m x 1.2 m) method and CH4 and N2O concentrations were determined using gas chromatographs. We found that emissions were significantly affected by the type and dose of mineral fertilizers. Application of

  7. Method of fission product beta spectra measurements for predicting reactor anti-neutrino emission

    Energy Technology Data Exchange (ETDEWEB)

    Asner, D.M.; Burns, K.; Campbell, L.W.; Greenfield, B.; Kos, M.S., E-mail: markskos@gmail.com; Orrell, J.L.; Schram, M.; VanDevender, B.; Wood, L.S.; Wootan, D.W.

    2015-03-11

    The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron-rich fission products that subsequently beta decay and emit electron antineutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to today's precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent reconsiderations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable isotopes placed in this tailored neutron flux will ultimately emit beta particles from the resultant fission products. Measurement of these beta particles in a time projection chamber with a perpendicular magnetic field provides a distinctive set of systematic considerations for comparison to the original seminal beta spectra measurements. Ancillary measurements such as gamma-ray emission and post-irradiation radiochemical analysis will further constrain the absolute normalization of beta emissions per fission. The requirements for unfolding the beta spectra measured with this method into a predicted reactor neutrino spectrum are explored.

  8. Measurements of the millimeter-wave spectrum of interstellar dust emission

    Science.gov (United States)

    Fischer, M. L.; Clapp, A.; Devlin, M.; Gundersen, J. O.; Lange, A. E.; Lubin, P. M.; Meinhold, P. R.; Richards, P. L.; Smoot, G. F.

    1995-01-01

    We report measurements of the differential brightness of interstellar dust emission near the Galactic plane and at high Galactic latitudes. The data were obtained as part of a program to measure anisotropy in the cosmic microwave background (CMB). The measurements were made with a 0.5 deg beam size and a 1.3 deg sinusoidal chop, in broad bands (Delta nu/nu approximately 0.3) centered near frequencies of 6, 9, and 12 cm(exp -1). A measurement made toward the Galactic plane, at longitude 1 = 23.7 deg, is compared with the contrast observed in the 100 micrometers IRAS data. Assuming the dust emission has a brightness I(sub nu) proportional to nu(sup n)B(sub nu)(T(sub d)), where B(sub nu) is the Planck function, a best fit yields n = 1.6 +/- 0.4, T(sub d) = 24 +/- 5 K. In a region near the star mu Pegasi (mu PEG l = 91 deg, b = -31 deg), the comparison of our data with the 100 micrometers IRAS data yields n = 1.4 +/- 0.4, and T(sub d) = 18 +/- 3 K. In a second region near the star gamma Ursa Minoris (GUM l = 108 deg, b = 41 deg), an upper limit is placed on contrast in dust emission. This upper limit is consistent with spectrum measured at mu PEG and the IRAS 100 micrometer emission contrast at GUM, which is approximately 8 times lower than mu PEG.

  9. Emission Spectroscopy and Radiometric Measurements in the NASA Ames IHF Arc Jet Facility

    Science.gov (United States)

    Winter, Michael W.; Raiche, George A.; Prabhu, Dinesh K.

    2012-01-01

    Plasma diagnostic measurement campaigns in the NASA Ames Interaction Heating Facility (IHF) have been conducted over the last several years with a view towards characterizing the flow in the arc jet facility by providing data necessary for modeling and simulation. Optical emission spectroscopy has been used in the plenum and in the free jet of the nozzle. Radiation incident over a probe surface has also been measured using radiometry. Plenum measurements have shown distinct radial profiles of temperature over a range of operating conditions. For cases where large amounts of cold air are added radially to the main arc-heated stream, the temperature profiles are higher by as much as 1500 K than the profiles assumed in flow simulations. Optical measurements perpendicular to the flow direction in the free jet showed significant contributions to the molecule emission through inverse pre-dissociation, thus allowing determination of atom number densities from molecular emission. This has been preliminarily demonstrated with the N2 1st Positive System. Despite the use of older rate coefficients, the resulting atom densities are reasonable and surprisingly close to flow predictions.

  10. Impact of cold temperature on Euro 6 passenger car emissions.

    Science.gov (United States)

    Suarez-Bertoa, Ricardo; Astorga, Covadonga

    2018-03-01

    Hydrocarbons, CO, NOx, NH 3 , N 2 O, CO 2 and particulate matter emissions affect air quality, global warming and human health. Transport sector is an important source of these pollutants and high pollution episodes are often experienced during the cold season. However, EU vehicle emissions regulation at cold ambient temperature only addresses hydrocarbons and CO vehicular emissions. For that reason, we have studied the impact that cold ambient temperatures have on Euro 6 diesel and spark ignition (including: gasoline, ethanol flex-fuel and hybrid vehicles) vehicle emissions using the World-harmonized Light-duty Test Cycle (WLTC) at -7 °C and 23 °C. Results indicate that when facing the WLTC at 23 °C the tested vehicles present emissions below the values set for type approval of Euro 6 vehicles (still using NEDC), with the exception of NOx emissions from diesel vehicles that were 2.3-6 times higher than Euro 6 standards. However, emissions disproportionally increased when vehicles were tested at cold ambient temperature (-7 °C). High solid particle number (SPN) emissions (>1 × 10 11 # km -1 ) were measured from gasoline direct injection (GDI) vehicles and gasoline port fuel injection vehicles. However, only diesel and GDI SPN emissions are currently regulated. Results show the need for a new, technology independent, procedure that enables the authorities to assess pollutant emissions from vehicles at cold ambient temperatures. Harmful pollutant emissions from spark ignition and diesel vehicles are strongly and negatively affected by cold ambient temperatures. Only hydrocarbon, CO emissions are currently regulated at cold temperature. Therefore, it is of great importance to revise current EU winter vehicle emissions regulation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Development of Standardized Mobile Tracer Correlation Approach for Large Area Emission Measurements (DRAFT UNDER EPA REVIEW)

    Science.gov (United States)

    Foster-wittig, T. A.; Thoma, E.; Green, R.; Hater, G.; Swan, N.; Chanton, J.

    2013-12-01

    Improved understanding of air emissions from large area sources such as landfills, waste water ponds, open-source processing, and agricultural operations is a topic of increasing environmental importance. In many cases, the size of the area source, coupled with spatial-heterogeneity, make direct (on-site) emission assessment difficult; methane emissions, from landfills for example, can be particularly complex [Thoma et al, 2009]. Recently, whole-facility (remote) measurement approaches based on tracer correlation have been utilized [Scheutz et al, 2011]. The approach uses a mobile platform to simultaneously measure a metered-release of a conservative gas (the tracer) along with the target compound (methane in the case of landfills). The known-rate tracer release provides a measure of atmospheric dispersion at the downwind observing location allowing the area source emission to be determined by a ratio calculation [Green et al, 2010]. Although powerful in concept, the approach has been somewhat limited to research applications due to the complexities and cost of the high-sensitivity measurement equipment required to quantify the part-per billion levels of tracer and target gas at kilometer-scale distances. The advent of compact, robust, and easy to use near-infrared optical measurement systems (such as cavity ring down spectroscopy) allow the tracer correlation approach to be investigated for wider use. Over the last several years, Waste Management Inc., the U.S. EPA, and collaborators have conducted method evaluation activities to determine the viability of a standardized approach through execution of a large number of field measurement trials at U.S. landfills. As opposed to previous studies [Scheutz et al, 2011] conduct