- Please check and comment entries here.
Real Driving Emissions
Air pollution caused by vehicle emissions has raised serious public health concerns. Vehicle emissions generally depend on many factors, such as the nature of the vehicle, driving style, traffic conditions, emission control technologies, and operational conditions. Concerns about the certification cycles used by various regulatory authorities are growing due to the difference in emission during certification procedure and Real Driving Emissions (RDE). Under laboratory conditions, certification tests are performed in a ‘chassis dynamometer’ for light-duty vehicles (LDVs) and an ‘engine dynamometer’ for heavy-duty vehicles (HDVs). As a result, the test drive cycles used to measure the automotive emissions do not correctly reflect the vehicle’s real-world driving pattern. Consequently, the RDE regulation is being phased to reduce the disparity between type approval and vehicle’s real-world emissions. According to this review, different variables such as traffic signals, driving dynamics, congestions, altitude, ambient temperature, and so on have a major influence on actual driving pollution. Aside from that, cold-start and hot-start have been shown to affect on-road pollution. Contrary to common opinion, new technology such as start-stop systems boost automotive emissions rather than decreasing them owing to unfavourable conditions from the point of view of exhaust emissions and exhaust after-treatment systems. In addition, the driving dynamics are not represented in the current laboratory-based test procedures. As a result, it is critical to establish an on-road testing protocol to obtain a true representation of vehicular emissions and reduce emissions to a standard level. The incorporation of RDE clauses into certification procedures would have a positive impact on global air quality.
2. Vehicle and Engine Test Cycle Basics
3. Legislative Test Drive Cycles for the Emission Type Approval
4. Development of Real Drive Emission Tests and Cycle
|Euro 6b||Euro 6c||Euro 6d|
|Development & Measurement Phase||Conformity Factor (CF)|
|CFNOx = 2.1, CFPN = 1.5||CFNOx, PN = 1.5|
|RDE for CO, NOX, PN emissions: EC 427/2016 and EC 646/2016||CO, NOX, PN and CO2|
|Speed (V)||km/h||V ≤ 60||60 < V||90 ≤ V ≤ 145||V > 100 for at least 5 min in motorway|
|Distance||% of total distance||29–44||33 ± 10||33 ± 10|
|Avg speed (Vavg)||km/h||15 ≤ Vavg ≤ 40||-||-|
|Number of stops||s||several > 10||-||-|
|Total test time||min||90 to 120|
|Elevating difference||m||100||Between the start and endpoint|
Urban driving must be achieved on routes with a maximum speed limit of 60 km/h.
If the urban driving segment includes any road with a speed limit greater than 60 km/h for any reason, the vehicle speed shall not exceed 60 km/h.
Roads with speed limits lower than the classification can exist in rural and freeway sections.
The road must be built such that the urban segment is travelled first, then the rural, and eventually the highway sections (using a topographical map).
It is necessary to operate the vehicle above 100 km/h (measured by the GPS) at least for 5 min.
The car must be capable of travelling at speeds ranging between 90 to 110 km/h.
5. Real Drive Emission Cycle Tests
Gasoline cars: i-pentane, acetone, propane, and toluene.
Light-duty diesel truck: mainly long-chain alkanes- dodecane, n-undecane, naphthalene and n-decane, which in total contributes to 70.4% of total species
Heavy-duty diesel truck: naphthalene contributed 31.8% of total VOC, which might be due to the engine operating conditions and the pyrolysation from incomplete combustion (Lin et al., 2019a, 2019b).
LPG bus: short-chain hydrocarbons, acetone, i-pentane, i-butane, n-butane and propane (46.7% of the total VOCs).
6. Comparison of RDE and laboratory testing
Degraeuwe and Weiss  compared NOX emissions from on-road testing and laboratory-based NEDC tests for diesel and gasoline vehicles. According to the authors, the NOX emissions of diesel engines in laboratory tests are below the emission level limit, but on-road emissions are far above the limit. The on-road emissions from gasoline vehicles are higher than the NEDC pollution values, but they are still within the emission limits. On-road NOX emissions for diesel cars are 181 percent higher than the NEDC average. Several national form approval authorities confirmed that tested vehicles emit emissions below the limit in a laboratory setting, but 4.5 to 4.7 times higher than the limit for EURO 5 and EURO 6 vehicles . In contrast to laboratory-based experiments, on-road tests released 50% more NOX, according to Pirjola et al. . Valverde et al.  conducted on-road and in-laboratory NEDC studies on diesel and gasoline vehicles. On-road emissions for diesel vehicles were 14 times higher than NEDC tests and 6 times higher than type approval limits, according to the authors. The authors also stated that PN emissions for diesel cars were below the TA limit in both on-road and laboratory tests, and CO2 emissions for on-road were marginally higher than the TA limit. On-road and in-lab NOX emissions from gasoline vehicles were within the TA cap. On-road emissions and chassis dynamometer-based in-lab measurements were compared by Besch et al. . The authors used two different routes with a Jeep Grand Cherokee and found that NOX emissions were significantly higher on both routes as compared to chassis dynamometer cycles. Park et al.  also reported that on-road NOX emission was five times higher than laboratory-based emission tests. On the contrary, Thomas et al.  reported 34% lower NOX emission and 60% lower CO emission compared to laboratory cycle-based emission results. The major factors for such discrepancies between on-road and laboratory-based emission findings are that on-road emissions are affected by various factors that are not considered in laboratory-based driving cycles, such as driver aggression, congestion, road gradient, etc. Furthermore, most authors indicated that NOX and PN emissions are the ones that differentiate from laboratory studies.
In recent years researchers have found a significant difference in emissions reported using type emission tests and on-road emission tests. The test drive cycles employed to measure the emissions produced by vehicles are expected to adequately represent the vehicle's real-world driving pattern to provide the most realistic estimation of these levels. However, which is not the case. Furthermore, two recent scandals have identified that auto manufacturing companies use emission defeat devices that would reduce vehicle emission by tracking when used in chassis dynamometer and enabling emission reduction techniques. These have resulted in researchers prioritising on-road emission tests known as RDE testing. The paper discusses RDE development methods and reviews past works. The review shows that various factors such as traffic signal, driving dynamics, congestions, altitude, ambient temperature etc., have a significant impact on on-road emissions. In addition, driving behaviour, along with the driving route, significantly impacts vehicle emission, which is not represented in type emission tests. For example, aggressive driving behaviour increased NOx and CO emissions three times than normal driving behaviour. Route characteristics such as traffic lights, right/left turns, roundabouts, gradients were all found to have a significant impact on vehicle emissions. The literature review also indicated that modern vehicle technologies such as start-stop systems also affect vehicle emission. The start-stop system results in increased emission due to the engine not operating in conditions intended, i.e. stoichiometric operation and operating temperatures because of frequent stops and starts. This contributes to the disturbance of the mixture composition (enrichment during acceleration, idle when reducing the rotational speed). These factors cause the engine to work on mixtures other than stoichiometric, i.e. unfavourable from the point of view of exhaust emissions and exhaust after-treatment systems. This also corroborates the fact that an internal combustion engine performs best under constant operating conditions. The driving dynamics are not represented in the current laboratory-based test procedures. Thus, it is important to consider all these factors when developing a real drive emission cycle to evaluate the emission level of any vehicle. This, in turn, will significantly improve the air quality around the world.
The entry is from 10.3390/en14144195
- Mofijur, M.; Fattah, I.R.; Alam, A.; Islam, A.S.; Ong, H.C.; Rahman, S.A.; Najafi, G.; Ahmed, S.; Uddin, A.; Mahlia, T. Impact of COVID-19 on the social, economic, environmental and energy domains: Lessons learnt from a global pandemic. Sustain. Prod. Consum. 2021, 26, 343–359.
- International Energy Agency (IEA). Global Energy Review. 2021. Available online: https://www.iea.org/reports/global-energy-review-2021 (accessed on 1 July 2021).
- Ritchie, H.; Roser, M. Emissions by Sector. Available online: https://ourworldindata.org/emissions-by-sector (accessed on 1 July 2021).
- Mengpin, G.; Johannes, F. 4 Charts Explain Greenhouse Gas Emissions by Countries and Sectors. Available online: https://www.climatewatchdata.org/ (accessed on 1 July 2021).
- McGrath, M. Climate Change and Coronavirus: Five Charts about the Biggest Carbon Crash. Available online: https://www.bbc.com/news/science-environment-52485712 (accessed on 24 September 2020).
- Johns Hopkins University (JHU). COVID-19 Dashboard by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins Coronavirus Resource Center. Global Map. Available online: https://coronavirus.jhu.edu/map.html. (accessed on 3 July 2021).
- Delphi Technologies. Current Emissions Standard Guides. Available online: https://www.delphi.com/innovations/emissions-standards-booklets (accessed on 24 September 2020).
- Al-Kindi, S.G.; Brook, R.D.; Biswal, S.; Rajagopalan, S. Environmental determinants of cardiovascular disease: Lessons learned from air pollution. Nat. Rev. Cardiol. 2020, 17, 656–672.
- Xie, J.; Teng, J.; Fan, Y.; Xie, R.; Shen, A. The short-term effects of air pollutants on hospitalizations for respiratory disease in Hefei, China. Int. J. Biometeorol. 2019, 63, 315–326.
- Van Mierlo, J.; Maggetto, G.; Van de Burgwal, E.; Gense, R. Driving style and traffic measures-influence on vehicle emissions and fuel consumption. Proc. Inst. Mech. Eng. Part D J. Automob. Eng. 2004, 218, 43–50.
- Perry, R.; Gee, I. Vehicle emissions in relation to fuel composition. Sci. Total Environ. 1995, 169, 149–156.
- Noland, R.B.; Quddus, M.A. Flow improvements and vehicle emissions: Effects of trip generation and emission control technology. Transp. Res. Part D Transp. Environ. 2006, 11, 1–14.
- Drozd, G.T.; Zhao, Y.; Saliba, G.; Frodin, B.; Maddox, C.; Weber, R.J.; Chang, M.-C.O.; Maldonado, H.; Sardar, S.; Robinson, A.L.; et al. Time Resolved Measurements of Speciated Tailpipe Emissions from Motor Vehicles: Trends with Emission Control Technology, Cold Start Effects, and Speciation. Environ. Sci. Technol. 2016, 50, 13592–13599.
- Franco, V.; Kousoulidou, M.; Muntean, M.; Ntziachristos, L.; Hausberger, S.; Dilara, P. Road vehicle emission factors development: A review. Atmos. Environ. 2013, 70, 84–97.
- Samuel, S.; Austin, L.; Morrey, D. Automotive test drive cycles for emission measurement and real-world emission levels-a review. Proc. Inst. Mech. Eng. Part D J. Automob. Eng. 2002, 216, 555–564.
- Kleeman, P. A fresh look at predicting carbon monoxide impacts at highway intersections. In Proceedings of the Transport Research Board A1 FC03-AIF06 Joint Summer Meeting, Ann Arbor, MI, USA, 11–15 January 1998.
- Varella, R.A.; Duarte, G.; Baptista, P.; Sousa, L.; Villafuerte, P.M. Comparison of Data Analysis Methods for European Real Driving Emissions Regulation. SAE Tech. Pap. Ser. 2017, 1, 997.
- Ashtari, A.; Bibeau, E.; Shahidinejad, S. Using Large Driving Record Samples and a Stochastic Approach for Real-World Driving Cycle Construction: Winnipeg Driving Cycle. Transp. Sci. 2014, 48, 170–183.
- Gong, Q.; Midlam-Mohler, S.; Marano, V.; Rizzoni, G. An Iterative Markov Chain Approach for Generating Vehicle Driving Cycles. SAE Int. J. Engines 2011, 4, 1035–1045.
- Nyberg, P.; Frisk, E.; Nielsen, L. Driving Cycle Equivalence and Transformation. IEEE Trans. Veh. Technol. 2017, 66, 1963–1974.
- Merkisz, J.; Pielecha, J. Comparison of Real Driving Emissions tests. IOP Conf. Ser. Mater. Sci. Eng. 2018, 421, 042055.
- Kamińska, M.; Rymaniak, Ł.; Lijewski, P.; Szymlet, N.; Daszkiewicz, P.; Grzeszczyk, R. Investigations of Exhaust Emissions from Rail Machinery during Track Maintenance Operations. Energies 2021, 14, 3141.
- Warguła, Ł.; Kukla, M.; Lijewski, P.; Dobrzyński, M.; Markiewicz, F. Influence of Innovative Woodchipper Speed Control Systems on Exhaust Gas Emissions and Fuel Consumption in Urban Areas. Energies 2020, 13, 3330.
- Waluś, K.J.; Warguła, Ł.; Krawiec, P.; Adamiec, J.M. Legal regulations of restrictions of air pollution made by non-road mobile machinery—The case study for Europe: A review. Environ. Sci. Pollut. Res. 2018, 25, 3243–3259.
- Rymaniak, Ł.; Lijewski, P.; Kamińska, M.; Fuć, P.; Kurc, B.; Siedlecki, M.; Kalociński, T.; Jagielski, A. The role of real power output from farm tractor engines in determining their environmental performance in actual operating conditions. Comput. Electron. Agric. 2020, 173, 105405.
- Warguła, Ł.; Kukla, M.; Lijewski, P.; Dobrzyński, M.; Markiewicz, F. Impact of Compressed Natural Gas (CNG) Fuel Systems in Small Engine Wood Chippers on Exhaust Emissions and Fuel Consumption. Energies 2020, 13, 6709.
- Warguła, Ł.; Kukla, M.; Lijewski, P.; Dobrzyński, M.; Markiewicz, F. Influence of the Use of Liquefied Petroleum Gas (LPG) Systems in Woodchippers Powered by Small Engines on Exhaust Emissions and Operating Costs. Energies 2020, 13, 5773.
- Mahlia, T.M.I.; Tohno, S.; Tezuka, T. A review on fuel economy test procedure for automobiles: Implementation possibilities in Malaysia and lessons for other countries. Renew. Sustain. Energy Rev. 2012, 16, 4029–4046.
- Hooftman, N.; Messagie, M.; Van Mierlo, J.; Coosemans, T. A review of the European passenger car regulations—Real driving emissions vs local air quality. Renew. Sustain. Energy Rev. 2018, 86, 1–21.
- Agarwal, A.K.; Mustafi, N.N. Real-world automotive emissions: Monitoring methodologies, and control measures. Renew. Sustain. Energy Rev. 2021, 137, 110624.
- Graham, L.A.; Rideout, G.; Rosenblatt, D.; Hendren, J. Greenhouse gas emissions from heavy-duty vehicles. Atmos. Environ. 2008, 42, 4665–4681.
- Ashraful, A.M.; Masjuki, H.H.; Kalam, M.A.; Fattah, I.M.R.; Imtenan, S.; Shahir, S.A.; Mobarak, H.M. Production and comparison of fuel properties, engine performance, and emission characteristics of biodiesel from various non-edible vegetable oils: A review. Energy Convers. Manag. 2014, 80, 202–228.
- Fattah, I.R.; Masjuki, H.; Liaquat, A.; Ramli, R.; Kalam, A.; Riazuddin, V. Impact of various biodiesel fuels obtained from edible and non-edible oils on engine exhaust gas and noise emissions. Renew. Sustain. Energy Rev. 2013, 18, 552–567.
- Giakoumis, E.G. Driving and Engine Cycles; Springer Science and Business Media LLC: Cham, Switzerland, 2017.
- Tzirakis, E.; Pitsas, K.; Zannikos, F.; Stournas, S. Vehicle emissions and driving cycles: Comparison of the Athens Driving Cycle (ADC) with ECE-15 and European Driving Cycle (EDC). Glob. NEST J. 2006, 8, 282–290.
- Lyons, T.; Kenworthy, J.; Austin, P.; Newman, P. The development of a driving cycle for fuel consumption and emissions evaluation. Transp. Res. Part A Gen. 1986, 20, 447–462.
- Kühler, M.; Karstens, D. Improved Driving Cycle for Testing Automotive Exhaust Emissions. SAE Tech. Pap. Ser. 1978.
- Tong, H.; Hung, W.; Cheung, C. Development of a driving cycle for Hong Kong. Atmos. Environ. 1999, 33, 2323–2335.
- Giakoumis, E.; Rakopoulos, C.; Dimaratos, A.M.; Rakopoulos, D.C. Exhaust emissions with ethanol or n-butanol diesel fuel blends during transient operation: A review. Renew. Sustain. Energy Rev. 2013, 17, 170–190.
- Andreae, M.; Salemme, G.; Kumar, M.; Sun, Z. Emissions Certification Vehicle Cycles Based on Heavy Duty Engine Test Cycles. SAE Int. J. Commer. Veh. 2012, 5, 299–309.
- Watson, H.; Milkins, E.; Braunsteins, J. Development of the Melbourne peak cycle. In Proceedings of the Second Conference on Traffic Energy and Emissions, Melbourne, Australia, 19–21 May 1982.
- Metwalley, S.M.; Abouel-Seoud, S.; Farahat, A.M. Determination of the catalytic converter performance of bi-fuel vehicle. J. Pet. Technol. Altern. Fuels 2011, 2, 111–131.
- Bullock, K.J. Driving cycles. In Proceedings of the Second Conference on Traffic, Energy and Emissions, Melbourne, Australia, 19–21 May 1982; pp. 1–18.
- Duarte, G.; Gonçalves, G.; Farias, T. Analysis of fuel consumption and pollutant emissions of regulated and alternative driving cycles based on real-world measurements. Transp. Res. Part D Transp. Environ. 2016, 44, 43–54.
- Pang, Y.; Fuentes, M.; Rieger, P. Trends in the emissions of Volatile Organic Compounds (VOCs) from light-duty gasoline vehicles tested on chassis dynamometers in Southern California. Atmos. Environ. 2014, 83, 127–135.
- Chen, L.; Wang, Z.; Liu, S.; Qu, L. Using a chassis dynamometer to determine the influencing factors for the emissions of Euro VI vehicles. Transp. Res. Part D Transp. Environ. 2018, 65, 564–573.
- Zhou, H.; Zhao, H.; Feng, Q.; Yin, Z.; Li, J.; Qin, K.; Li, M.; Cao, L. Effects of environmental parameters on real-world nox emissions and fuel consumption for heavy-duty diesel trucks using an OBD approach; 0148-7191. SAE Tech. Pap. 2018, 1, 1817.
- Betageri, V.; Mahesh, R. Effects of the Real Driving Conditions on the NOx Emission of a Medium Duty Diesel Commercial Vehicle. SAE Tech. Pap. Ser. 2017.
- Bodisco, T.; Zare, A. Practicalities and Driving Dynamics of a Real Driving Emissions (RDE) Euro 6 Regulation Homologation Test. Energies 2019, 12, 2306.
- The Association for Emissions Control by Catalyst (AECC). Real Driving Emissions. Available online: https://www.aecc.eu/legislation/light-duty-vehicles/real-driving-emissions/ (accessed on 5 February 2021).
- Donateo, T.; Giovinazzi, M. Building a cycle for Real Driving Emissions. Energy Procedia 2017, 126, 891–898.
- Roberts, P.J.; Mumby, R.; Mason, A.; Redford-Knight, L.; Kaur, P. RDE Plus—The Development of a Road, Rig and Engine-in-the-Loop Test Methodology for Real Driving Emissions Compliance. SAE Tech. Pap. Ser. 2019.
- Zhang, Y.; Tian, D.; Du, H.; Pan, H.; Fang, W.; Wang, Y. Design and Research of RDE Test Routes. In Advances in Intelligent Systems and Computing; Springer Science and Business Media LLC: Cham, Switzerland, 2019; pp. 1160–1169.
- Tong, H.; Tung, H.; Hung, W.-T.; Nguyen, H. Development of driving cycles for motorcycles and light-duty vehicles in Vietnam. Atmos. Environ. 2011, 45, 5191–5199.
- Yang, Z.; Liu, Y.; Wu, L.; Martinet, S.; Zhang, Y.; Andre, M.; Mao, H. Real-world gaseous emission characteristics of Euro 6b light-duty gasoline- and diesel-fueled vehicles. Transp. Res. Part D Transp. Environ. 2020, 78, 102215.
- Thomas, D.; Li, H.; Wang, X.; Song, B.; Ge, Y.; Yu, W.; Ropkins, K. A Comparison of Tailpipe Gaseous Emissions for RDE and WLTC Using SI Passenger Cars. SAE Tech. Pap. Ser. 2017, 1.
- Wang, M.; Li, S.; Zhu, R.; Zhang, R.; Zu, L.; Wang, Y.; Bao, X. On-road tailpipe emission characteristics and ozone formation potentials of VOCs from gasoline, diesel and liquefied petroleum gas fueled vehicles. Atmos. Environ. 2020, 223, 117294.
- Du, B.; Zhang, L.; Geng, Y.; Zhang, Y.; Xu, H.; Xiang, G. Testing and evaluation of cold-start emissions in a real driving emissions test. Transp. Res. Part D Transp. Environ. 2020, 86, 102447.
- Jaiprakash; Habib, G. On-road assessment of light duty vehicles in Delhi city: Emission factors of CO, CO2 and NOX. Atmos. Environ. 2018, 174, 132–139.
- Cao, X.; Yao, Z.; Shen, X.; Ye, Y.; Jiang, X. On-road emission characteristics of VOCs from light-duty gasoline vehicles in Beijing, China. Atmos. Environ. 2016, 124, 146–155.
- Daham, B.; Li, H.; Andrews, G.E.; Ropkins, K.; Tate, J.E.; Bell, M. Comparison of Real World Emissions in Urban Driving for Euro 1-4 Vehicles Using a PEMS. SAE Tech. Pap. Ser. 2009.
- Roso, V.; Martins, M.E.S. Simulation of Fuel Consumption and Emissions for Passenger Cars and Urban Buses in Real-World Driving Cycles. SAE Tech. Pap. Ser. 2016, 1.
- Akard, M.; Gramlich, N.; Nevius, T.; Porter, S. Comparison of Real-World Urban Driving Route PEMS Fuel Economy with Chassis Dynamometer CVS Results. SAE Tech. Pap. Ser. 2019.
- Ren, Y.; Lou, D.; Zhang, Y.; Tan, P.; Hu, Z. Study on Real-World NOx and Particle Emissions of Bus: Influences of VSP and Fuel. SAE Tech. Pap. Ser. 2019.
- Gallus, J.; Kirchner, U.; Vogt, R.; Börensen, C.; Benter, T. On-road particle number measurements using a portable emission measurement system (PEMS). Atmos. Environ. 2016, 124, 37–45.
- Braisher, M.; Stone, R.; Price, P. Particle Number Emissions from a Range of European Vehicles. SAE Tech. Pap. Ser. 2010.
- Khalfan, A.; Andrews, G.; Li, H. Real World Driving: Emissions in Highly Congested Traffic. SAE Tech. Pap. Ser. 2017, 1.
- Rosenblatt, D.; Stokes, J.; Caffrey, C.; Brown, K.F. Effect of Driving Cycles on Emissions from On-Road Motorcycles. SAE Tech. Pap. Ser. 2020.
- Fonseca, N.; Casanova, J.; Valdés, M. Influence of the stop/start system on CO2 emissions of a diesel vehicle in urban traffic. Transp. Res. Part D Transp. Environ. 2011, 16, 194–200.
- Warguła, Ł.; Krawiec, P.; Waluś, K.J.; Kukla, M. Fuel Consumption Test Results for a Self-Adaptive, Maintenance-Free Wood Chipper Drive Control System. Appl. Sci. 2020, 10, 2727.
- Zsiga, N.; Ritzmann, J.; Soltic, P. Practical Aspects of Cylinder Deactivation and Reactivation. Energies 2021, 14, 2540.
- Parker, M.C.; Jiang, C.; Butcher, D.; Spencer, A.; Garner, C.P.; Witt, D. Impact and observations of cylinder deactivation and reactivation in a downsized gasoline turbocharged direct injection engine. Int. J. Engine Res. 2021, 22, 1367–1376.
- Savickas, D.; Steponavičius, D.; Domeika, R. Analysis of Telematics Data of Combine Harvesters and Evaluation of Potential to Reduce Environmental Pollution. Atmosphere 2021, 12, 674.
- Dvorkin, W.; King, J.; Gray, M.; Jao, S. Determining the Greenhouse Gas Emissions Benefit of an Adaptive Cruise Control System Using Real-World Driving Data. SAE Tech. Pap. Ser. 2019.
- Laberteaux, K.; Hamza, K. A Study of Greenhouse Gas Emissions Reduction Opportunity in Light-Duty Vehicles by Analyzing Real Driving Patterns. SAE Tech. Pap. Ser. 2017, 1.
- Andersson, J.; May, J.; Favre, C.; Bosteels, D.; De Vries, S.; Heaney, M.; Keenan, M.; Mansell, J. On-Road and Chassis Dynamometer Evaluations of Emissions from Two Euro 6 Diesel Vehicles. SAE Int. J. Fuels Lubr. 2014, 7, 919–934.
- Wang, H.; Wu, Y.; Zhang, K.M.; Zhang, S.; Baldauf, R.W.; Snow, R.; Deshmukh, P.; Zheng, X.; He, L.; Hao, J. Evaluating mobile monitoring of on-road emission factors by comparing concurrent PEMS measurements. Sci. Total Environ. 2020, 736, 139507.
- Park, J.; Shin, M.; Lee, J.; Lee, J. Estimating the effectiveness of vehicle emission regulations for reducing NOx from light-duty vehicles in Korea using on-road measurements. Sci. Total Environ. 2021, 767, 144250.
- Bischoff, G.; Keller, S.; Heubuch, A. Portable Emission Measurement Technology and RDE on Motorcycles as Instruments for Future Challenges. MTZ Worldw. 2020, 81, 54–59.
- Degraeuwe, B.; Weiss, M. Does the New European Driving Cycle (NEDC) really fail to capture the NOX emissions of diesel cars in Europe? Environ. Pollut. 2017, 222, 234–241.
- Mathews, L.T.; Neti, R.M. Vehicle Emissions Testing System. Google Patents 5,753,185, 19 May 1998.
- BMVI (Bundesministerium Für Verkehr und Digitale Infrastruktur). Bericht der Untersuchungskommission Volkswagen. Available online: https://www.autoevolution.com/pdf/news_attachements/630000-diesel-cars-of-german-origin-to-be-recalled-in-europe-more-to-follow-106820.pdf (accessed on 1 July 2021).
- Pirjola, L.; Rönkkö, T.; Saukko, E.; Parviainen, H.; Malinen, A.; Alanen, J.; Saveljeff, H. Exhaust emissions of non-road mobile machine: Real-world and laboratory studies with diesel and HVO fuels. Fuel 2017, 202, 154–164.
- Valverde, V.; Mora, B.; Clairotte, M.; Pavlovic, J.; Suarez-Bertoa, R.; Giechaskiel, B.; Astorga-Llorens, C.; Fontaras, G. Emission Factors Derived from 13 Euro 6b Light-Duty Vehicles Based on Laboratory and On-Road Measurements. Atmosphere 2019, 10, 243.
- Besch, M.C.; Chalagalla, S.H.; Carder, D. On-Road and Chassis Dynamometer Testing of Light-duty Diesel Passenger Cars. Available online: https://www.cafee.wvu.edu/files/d/c586c1dd-b361-410d-a88d-d34e8834eda6/testing-of-light-duty-diesel-passenger-cars.pdf (accessed on 1 July 2021).