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Artykuły w czasopismach na temat "Passenger vehicles kilometres"
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Kliučininkas, Linas, Simona Balkevičiene i Jolita Mockuviene. "MODELLING OF TRAFFIC POLICY MEASURES FOR AMBIENT AIR QUALITY MANAGEMENT". Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 1 (18.06.2005): 187. http://dx.doi.org/10.17770/etr2005vol1.2133.
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This paper presents the application of the Integrated Transport Effect Modeling System ITEMS, taking into consideration existing vehicle fleet, traffic flows, and ambient air quality monitoring data. The objective of this study is to estimate the exhausts of CO, NOx, and SO2 released by motor vehicles in relation to predictive traffic policy measures in Kaunas, Lithuania.This study analyses the extent to which some traffic policies and future trends may influence the ambient air pollution in urban environment. Three traffic policy measures such as: i) increase of car parking fee; ii) reduction of car parking places; iii) introduction of dedicated traffic lines for public transport are considered as the case studies to examine the extend to which they could reduce emissions from motor vehicles. At the same time, each policy measure comprises four scenarios including one, which indicates the current situation. The comparative analyses of the influence of different traffic policy measures on vehicle/passenger kilometres travelled and on emissions are presented.
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Maslina, Maslina, i Bima Dhevrando. "ANALISIS KESELAMATAN LALU-LINTAS JL.SOEKARNO HATTA BALIKPAPAN". INFO-TEKNIK 20, nr 1 (20.06.2020): 1. http://dx.doi.org/10.20527/infotek.v20i1.6951.
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Soekarno Hatta Road is one of the road shaft beetween Balikpapan and Samarinda which has 119 kilometres long. This road is province roads that had been through out or passed by with typical heavy and light vehicles which has high intensity accident level. This research is aimed to devise factor and characteristic of accidents along Sokearno Hatta roads from zero kilometres until 13th kilometres.
This research begun with roads survey observation and secondary data collection including with roads accidents documents for the pass 3 years.( which is in years of 2015 – 2017). Data analysis prepared with calculating numbers of accidents using formula EAN (Equivalent Accidents Number) and UCL Method (Upper Control Limit) for determination area with high risk accidents (Black Spot). Anatomy Accidents Data Documents were enumerated to analyze in that specified area. That can be conclude that the numbers of accidents on Soekarno Hatta Street from zero kilometres until 13th kilometreswith EAN method i.g : more than 84 times bigger different from UCL value i.g: 43,3. Accidents that was happened in the mornings at weekdays Monday to Friday which were implicate 2 motorcycles and passenger in fifthteen till twenty years old students (boys).
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Liu, Yingying, Xueyan Zhao, Jing Wang, Shengnan Zhu, Bin Han, Di Zhao, Xinhua Wang i Chunmei Geng. "A Comprehensive 2018-Based Vehicle Emission Inventory and Its Spatial–Temporal Characteristics in the Central Liaoning Urban Agglomeration, China". International Journal of Environmental Research and Public Health 19, nr 4 (11.02.2022): 2033. http://dx.doi.org/10.3390/ijerph19042033.
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Rapid economic expansion and urbanisation have seriously affected the atmospheric environmental quality of the Central Liaoning Urban Agglomeration (CLUA). This study aimed to establish a detailed vehicle emission inventory of the CLUA with a 3 km × 3 km gridded spatiotemporal distribution. A top-down methodology using vehicle kilometres travelled annually, emission factors, and activity data of each city was established. Carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), ammonia (NH3), volatile organic compounds (VOCs), particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5), particulate matter with an aerodynamic diameter less than 10 μm (PM10), Black Carbon (BC), and organic carbon (OC) emissions were 291.0, 221.8, 3.6, 2.2, 42.8, 9.3, 10.3, 5.2, and 1.6 Gg in 2018, respectively. The contribution of diesel heavy-duty trucks to NOx, SO2, PM2.5, PM10, BC, and OC emissions was greater than 54.5%, the largest contribution of all vehicles. Gasoline small passenger vehicles were the primary contributor to CO, VOC, and NH3 emissions, contributing 37.3%, 39.5%, and 75.3% of total emissions, respectively. For emission standards, Pre-China 1 vehicles were the largest contributor to CO and VOC emissions and China 3 vehicles contributed the largest amount of NOx, SO2, PM2.5, PM10, BC, and OC emissions. The spatial distribution of pollutants showed “obvious lines” and grids with high emissions were concentrated in expressways, national highways, and provincial highways. The temporal variation showed morning–evening peaks during diurnal variations, which was consistent with resident behaviour. This work can help us understand vehicular emission characteristics of the CLUA and provide basic data for air quality modelling. Future research should investigate traffic flow by vehicle types and emission factors at a local level, which will be helpful for transport management planning.
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Teske, Sven, Stefan Bratzel, Ralf Tellermann, Benjamin Stephan i Mauricio Vargas. "Net Zero: The Remaining Global Market Volume for Internal Combustion Engines in Light-Duty Vehicles under a 1.5 °C Carbon Budget Trajectory". Energies 15, nr 21 (28.10.2022): 8037. http://dx.doi.org/10.3390/en15218037.
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To achieve the goals of the Paris Climate Agreement, decarbonization targets for the global automotive industry are required. We assess the quantity of light-duty vehicles (LDVs) with internal combustion engines (ICEs) that can be manufactured within the identified carbon budget and compare it with the current sales plans of the four largest automobile manufacturers—Volkswagen, General Motors, Toyota, and Hyundai/Kia—as representative of traditional car manufacturers. We first describe the quantification of a carbon budget for LDVs under the 1.5 °C target and a methodology for calculating the market shares that will allow different drive-train technologies to stay within it. The global LDV market for new sales and historic and future vehicle retirement rates are presented, together with assumptions for car usage (in passenger kilometres per year) and fuel efficiencies. We calculate the quantity of ICE LDVs that can be sold before the manufacture of ICEs must cease globally. We then compare this upper global limit with the current sales plans of car companies. The plans of the four manufacturers differ, but all considerably exceed the number of ICE vehicle sales required to meet the 1.5 °C target. This analysis does not forecast the development of the global LDV market, but assesses the gap between manufacturers’ intention and the requirement under a 1.5 °C pathway.
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Babanoski, Kire, Ice Ilijevski i Zlate Dimovski. "Analysis of Road Traffic Safety through Direct Relative Indicators for Traffic Accidents Fatality: Case of Republic of Macedonia". PROMET - Traffic&Transportation 28, nr 6 (19.12.2016): 661–69. http://dx.doi.org/10.7307/ptt.v28i6.2137.
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In the absence of a detailed profile and assessment of the road traffic safety situation in the Republic of Macedonia, the paper will show the analysis by calculating and comparing the direct relative indicators for deaths from traffic accidents in relation to the total population (public risk), the total number of vehicles (traffic risk) and the total number of passenger-kilometres (dynamic traffic risk). Their established trends in the period 2005-2014 will also be shown and then compared with the levels in other European countries. Within the risks, there is additionally the risk of suffering that takes into account the consequences of accidents to people (human losses, heavy and light bodily injuries), which will be calculated and analysed for the area covered by the eight Sectors for Internal Affairs (SIA) in the Republic of Macedonia. For this purpose maps of the public risk of suffering from accidents on the roads will be made, which will closely show the traffic safety situation in the country. The diagnosing of the traffic safety situation will contribute to the creation of new measures and activities or improving the existing ones by the competent authorities in order to promote the road traffic safety.
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SZYMLET, Natalia, Piotr LIJEWSKI, Łukasz RYMANIAK, Barbara SOKOLNICKA i Maciej SIEDLECKI. "Comparative analysis of exhaust emissions from passenger cars and motorcycles". Combustion Engines 177, nr 2 (1.05.2019): 19–22. http://dx.doi.org/10.19206/ce-2019-204.
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The subject of this article is a comparative analysis of exhaust emissions for: HC (hydrocarbons), CO (carbon monoxide), CO2 (car-bon dioxide), NOx (nitrogen oxides) from a passenger vehicle and a motorcycle in laboratory conditions on a dynamometer station. The first vehicle category was represented by a compression-ignition engine with a displacement volume of 1.3 dm3 and a power of 66 kW. The exhaust aftertreatment system included a catalytic converter and a particulate filter. The second category was a motorcycle, equipped with an engine with a displacement of 0.7 dm3 and a maximum power of 55 kW. The two-wheeled vehicle was equipped with a three-way catalytic converter. Speeds were modeled on the European type approval test – NEDC (New European Driving Cycle). In order to conduct a comparative analysis of exhaust emissions and fuel consumption from vehicles of different categories, the obtained results were presented in the form of emissions converted into passenger-kilometers (g/pkm). The research used modern equipment belonging to the PEMS (Portable Emissions Measurement Systems) group of devices. The analyzes carried out enable the decision mak-ing on which vehicles have a greater environmental impact due to their exhaust emissions, taking into account the distance and the number of passengers carried.
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Utama, Muhammad Gemilang P., i Nirwana Puspasari. "Analisa Biaya Operasional Kendaraan Bus Angkutan Kota Jurusan Palangka Raya-Pangkalan Bun". Media Ilmiah Teknik Sipil 8, nr 2 (1.06.2020): 96–103. http://dx.doi.org/10.33084/mits.v8i2.1407.
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Transportation is an important role in aspects of social economic and cultural activities. Based on the distribution of passenger traffic in and out of the land transportation, the Bus fleet majoring in Palangkaraya-Pangkalan Bun is the most desirable transportation service because travel times are faster and more efficient. The research objective is to determine the magnitude of operational costs for public transportation vehicles Palangka Raya-Pangkalan Bun. The method of collecting passenger data and bus fleet data is a non-random sampling method. Primary data in the form of vehicle operating costs are analyzed by the method of cost per kilometer approach for each vehicle, revenue is analyzed by the method of approaching the average amount of revenue of the company per year and subtracted by total vehicle operating costs per kilometer, rates are analyzed by the method of adding the fixed cost components, costs variable and overhead costs in units per passenger and Fare Box Ratio (FBR) are analyzed using the method of comparing the value of Vehicle Operating Costs per year with annual income. From the results of the study, the amount of Operational Cost needs is spent at 81% of annual income. With a Factor Load calculation of 12 passengers per Trip over the past three years. The fare incurred for ticket purchase per one time departure is Rp 130,000.00 with a Fare Box Ratio (FBR) of 123% so that it can be categorized as a profit
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Liyanage, Sohani, i Hussein Dia. "An Agent-Based Simulation Approach for Evaluating the Performance of On-Demand Bus Services". Sustainability 12, nr 10 (18.05.2020): 4117. http://dx.doi.org/10.3390/su12104117.
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On-demand multi-passenger shared transport options are increasingly being promoted as an influential strategy to reduce traffic congestion and emissions and improve the convenience and travel experience for passengers. These services, often referred to as on-demand public transport, are aimed at meeting personal travel demands through the use of shared vehicles that run on flexible routes using advanced tools for dynamic scheduling. This paper presents an agent-based traffic simulation model that was developed to evaluate the performance of on-demand public transport and compare it with existing scheduled bus services using a case study of the inner city of Melbourne in Australia. The key performance measures used in the comparative evaluation included quality of service and passenger experience in terms of waiting times, the efficiency of service and operations in terms of hourly vehicle utilization, and system efficiency in terms of trip completion rates, passenger kilometers travelled and total passenger trip times. The results showed significant benefits for passengers who use on-demand bus services compared to scheduled bus services. The on-demand bus service was found to reduce average total passenger waiting times by 89% during the Morning Peak; by 78% during the Mid-Day period; by 81% during the Afternoon Peak; and by more than 95% during other periods of the day. From an operator’s perspective, the on-demand services were found to achieve around 70% vehicle utilization rates during peak hours compared to a utilization rate not exceeding 16% for the scheduled bus services. Even during off-peak periods, the occupancies for on-demand services were almost twice the vehicle occupancies for scheduled bus services. In terms of system efficiency, the on-demand services achieved a trip completion rate of 85% compared to a trip completion rate of 67% for the scheduled bus services. The total passenger-kilometers travelled was similar for both scheduled and on-demand bus services, which refutes claims that on-demand bus services induce more kilometers of travel. The trip completion times were around 55% shorter for on-demand bus services compared to scheduled services, which represents a significant saving in travel time for users. Finally, the paper presents average emissions per completed trip for both types of services and shows a significant reduction in emissions for on-demand services compared to conventional bus services. These include, on average, a 48% reduction in CO2 emissions per trip; 82% reduction in NO emissions per trip; and 41% reduction in p.m.10 emissions per trip. These findings clearly demonstrate the superior benefits of on-demand bus services compared to scheduled bus services.
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Narváez-Villa, Paúl, Blanca Arenas-Ramírez, José Mira i Francisco Aparicio-Izquierdo. "Analysis and Prediction of Vehicle Kilometers Traveled: A Case Study in Spain". International Journal of Environmental Research and Public Health 18, nr 16 (6.08.2021): 8327. http://dx.doi.org/10.3390/ijerph18168327.
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Knowledge of the kilometers traveled by vehicles is essential in transport and road safety studies as an indicator of exposure and mobility. Its application in the determination of user risk indices in a disaggregated manner is of great interest to the scientific community and the authorities in charge of ensuring road safety on highways. This study used a sample of the data recorded during passenger vehicle inspections at Vehicle Technical Inspection stations and housed in a data warehouse managed by the General Directorate for Traffic of Spain. This study has three notable characteristics: (1) a novel data source is explored, (2) the methodology developed applies to other types of vehicles, with the level of disaggregation the data allows, and (3) pattern extraction and the estimate of mobility contribute to the continuous and necessary improvement of road safety indicators and are aligned with goal 3 (Good Health and Well-Being: Target 3.6) of The United Nations Sustainable Development Goals of the 2030 Agenda. An Operational Data Warehouse was created from the sample received, which helped in obtaining inference values for the kilometers traveled by Spanish fleet vehicles with a level of disaggregation that, to the knowledge of the authors, was unreachable with advanced statistical models. Three machine learning methods, CART, random forest, and gradient boosting, were optimized and compared based on the performance metrics of the models. The three methods identified the age, engine size, and tare weight of passenger vehicles as the factors with greatest influence on their travel patterns.
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Ehrenberger, Simone, Isheeka Dasgupta, Mascha Brost, Laura Gebhardt i Robert Seiffert. "Potentials of Light Electric Vehicles for Climate Protection by Substituting Passenger Car Trips". World Electric Vehicle Journal 13, nr 10 (2.10.2022): 183. http://dx.doi.org/10.3390/wevj13100183.
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For the transformation of the mobility sector, small and light electric vehicles (LEV) show great promise, owing to their efficiency and low vehicle weight resulting in low energy consumption and lower greenhouse gas emissions per driven kilometer. The presented study focuses on the theoretical potential of substitutability of passenger car trips in Germany by varied LEVs based on the “Mobilität in Deutschland 2017” (“Mobility in Germany 2017”) dataset, for the year 2030. A detailed approach for identifying substitutable car trips was developed, reflecting age, trip purpose, number of passengers, and other decision criteria. By conducting a life cycle assessment of the considered LEVs and passenger cars, potential emission savings were analyzed. In the considered baseline scenario, it is found that emissions could be reduced by 44 % with 50% of passenger car mileage being substituted by LEVs. This study, thereby, gives way to further research on LEVs, and would urge both policy makers and general users to steer towards comprehensive measures that encourage a switch from cars to LEVs.
Rozprawy doktorskie na temat "Passenger vehicles kilometres"
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Villamar, Daniel. "Chemins énergétiques à long terme en Équateur : scénarios de transition pour le secteur des transports jusqu'en 2050". Electronic Thesis or Diss., Perpignan, 2023. http://www.theses.fr/2023PERP0014.
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Cette thèse explore l'utilisation de modèles mathématiques pour accompagner une transition énergétique à faible émission de carbone pour l'Equateur. Une première approche considère une optimisation linéaire pour évaluer l'expansion des secteurs de l'énergie et de l'utilisation des terres et le modèle intégré ELENA est utilisé. Il est combiné avec le modèle de répartition urbs pour aller plus loin dans l'évaluation du système électrique face à une massification du transport électrique et il est également considéré dans le contexte d'une étude de synthèse axée sur la décarbonisation du secteur des bâtiments. La seconde approche de modélisation utilise les concepts de la théorie des jeux et plus particulièrement les modèles Single-Leader-Multi-Follower (SLMF). Une mise en oeuvre du modèle SLMF est effectuée pour le transport de marchandises afin de saisir l'effet d'une taxe carbone dans la transition vers des véhicules plus propres. Ce travail souligne la nécessité d'utiliser plusieurs modèles afin d'avoir une meilleure idée des interactions et des mesures à mettre en place pour soutenir la transition énergétique. Bien que l'étude soit réalisée pour l'Equateur, les méthodologies sont d'application généraleThis thesis explores the use of mathematical models to support a low carbon energy transition for Ecuador. Afirst approach considers a least-cost linear optimisation to evaluate the expansion of energy and land-use sectors and the integrated model ELENA is used. It is combined with the dispatch model urbs to go further in the evaluation of electric system face to a massification of electric transport and it is also considered on the context of a synthesis study focused on the ecarbonization of the Buildings Sector. The secondmodelling approach uses concepts of game theory and specifically of Single-Leader-Multi-Follower (SLMF) models. An implementation of the SLMF model is done for freight transport to capture the effect of a carbon tax in the transition to cleaner vehicles. This work highlights the need to use multiple models in order to have a better idea of the interactions and measures to be put in place to support the energy transition. Although the study is carried out for Ecuador, the methodologies are of general applicability
Części książek na temat "Passenger vehicles kilometres"
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Debbarma, Sohana, i Geetanjali Kaushik. "Assessing the impact of Transportation on Climate Change". W Handbook of Research on Environmental Policies for Emergency Management and Public Safety, 275–99. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3194-4.ch015.
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India's North-East Region has greater demand for road and personalized modes of transport powered by fossil fuels. And due to emissions, there has been evidence of climate change. It has been found that diesel cars cause greater emissions (per kilometer travelled) as compared to petrol cars; therefore, the use of diesel should be discouraged. The chapter suggests that the emissions in case of public transport passenger-km are lesser than other modes of transport. However, in the North-East Region, there is negligible share of public transport due to poor infrastructure and service facilities. Therefore, improvements should be made with regard to public transport system so that considerable number of passengers shifts to public transport modes. Further, it is inferred that use of alternate vehicle or fuel technologies like hybrid electric vehicles, biofuel, biodiesel, hydrogen fuel need to be initiated to mitigate the climate change.
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Debbarma, Sohana, i Geetanjali Kaushik. "Assessing the impact of Transportation on Climate Change". W Research Anthology on Environmental and Societal Impacts of Climate Change, 156–80. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-3686-8.ch009.
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India's North-East Region has greater demand for road and personalized modes of transport powered by fossil fuels. And due to emissions, there has been evidence of climate change. It has been found that diesel cars cause greater emissions (per kilometer travelled) as compared to petrol cars; therefore, the use of diesel should be discouraged. The chapter suggests that the emissions in case of public transport passenger-km are lesser than other modes of transport. However, in the North-East Region, there is negligible share of public transport due to poor infrastructure and service facilities. Therefore, improvements should be made with regard to public transport system so that considerable number of passengers shifts to public transport modes. Further, it is inferred that use of alternate vehicle or fuel technologies like hybrid electric vehicles, biofuel, biodiesel, hydrogen fuel need to be initiated to mitigate the climate change.
Streszczenia konferencji na temat "Passenger vehicles kilometres"
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Dunn, Ashley L., i Thomas A. Timbario. "Vehicle Dynamics Modeling of Commercial Vehicle Steer Axle Tire Disablements at Highway Speeds". W WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2023. http://dx.doi.org/10.4271/2023-01-0665.
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<div class="section abstract"><div class="htmlview paragraph">There have been many studies regarding the stability of vehicles following a sudden air loss event in a tire. Previous works have included literature reviews, full-scale vehicle testing, and computer modeling analyses. Some works have validated physics-based computer vehicle simulation models for passenger vehicles and other works have validated models for heavy commercial vehicles. This work describes a study wherein a validated vehicle dynamics computer model has been applied to extrapolate results to higher event speeds that are consistent with travel speeds on contemporary North American highways. This work applies previously validated vehicle dynamics models to study the stability of a five-axle commercial tractor-semitrailer vehicle following a sudden air loss event for a steer axle tire. Further, the work endeavors to understand the analytical tire model for tires that experience a sudden air loss. The studies discussed include executing physics-based vehicle dynamics models at speeds ranging from 88.5 kilometers per hour (55 miles per hour) up to 125.5 kilometers per hour (78 miles per hour), at various vehicle loading conditions and differing levels of velocity-dependent rolling resistance. The effects of speed and payload on vehicle response are analyzed and discussed.</div><div class="htmlview paragraph">For all the simulations in this study, a left steer axle tire sudden deflation was modeled. The results of the work revealed that after a modeled sudden air loss event, a manageable steering wheel angle would have to be input into the tractor steering system to arrest the initial yaw to the left caused by unbalanced longitudinal forces on the steer axle. The resultant initial corrective steer angle was found to be consistent with testing results and was in the range of 36 to 59 degrees steering wheel angle (SWA). As control of the tractor-semitrailer is maintained, the steering wheel angle required to hold the vehicle in a lane, steady-state, was found to be in the range of 24 to 38 degrees SWA.</div></div>
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Mapelli, Ferdinando Luigi, Davide Tarsitano, Davide Annese, Marco Sala i Giorgio Bosia. "A Study of Urban Electric Bus With Hybrid Energy Storage System Based on Battery and Supercapacitors". W ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63423.
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Nowadays considerable resources have been invested on low emission passenger vehicle both for private and public transportation. A feasible solution for urban buses is a full electrical traction system fed by supercapacitor that can be recharged at each bus stop while people are getting on and off. Such vehicle covers a short distance between consecutive stops, usually less than half a kilometer. An energy storage system able to provide high power peaks and small amount of energy is required. For these reasons, supercapacitors, which are capable of fast charging during bus stops, appear the most appropriate storage devices [1]. In order to consider the worst operating condition for the bus (like traffic jam of higher distance to be covered), a conventional battery is also installed, getting an hybrid energy storage system. An energy management function, able to manage the energy storage system, has been developed and validated by means of a numerical simulation model.
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Boggess, Brian M., Harold H. Ralston, Dusty A. Boyd, Bryan E. Strawbridge, Douglas R. Morr, Ashley L. Dunn i Elaine K. Castro. "Lane Change Dynamics of a Commercial Tractor-Trailer". W ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11479.
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Abstract A number of vehicle-to-vehicle accidents occur as a result of significant differentials in speed and lane changes between traffic in laterally offset lane positions. These analyses can include many scenarios. One typical scenario is the merging of an articulated commercial vehicle from a roadway shoulder or on-ramp into a travel lane at a relatively low speed compared to the posted speed limit and/or actual travel speed of established lane traffic. Collisions arising during such events often involve less than full engagement between the vehicles and are complicated by the extended length (20 meters (m) (65.6 feet (ft)) or more) of most combination units and its effect on the time and distance it takes the unit to transition from one lane to another. Vehicle dynamics is used to analyze and understand the lane change dynamics in order to assess causes of accidents, as well as aide engineers in creating safeguards to avoid such accidents. A review of currently available analytical models finds that most are based on an analysis of a single-point object or a standard, non-articulated passenger vehicle. Additionally, many of these models consider either a constant lateral acceleration profile or a half-sine acceleration profile with specified peak lateral acceleration resulting in a constant lane change time regardless of vehicle longitudinal speed. When considering the actual lane change dynamics of a tractor-trailer, the typically applied predictive models are limited to predicting the dynamics of a singular point on the tractor-trailer during the lane change as opposed to more specific dynamics of the tractor and trailer combined effect. Testing in this study was completed using a conventional truck-tractor with sleeper berth, coupled to an unloaded 40-foot trailer chassis with a container. A total of 23 tests were completed, including (a) constant speed maneuvers for travel speeds ranging from 8.0 to 67.6 kilometers per hour (kph) (5.0 to 42.0 miles per hour (mph)) and (b) continuously accelerating travel speeds with lane changes initiated at 10.5 to 27.4 kph (6.5 to 17.0 mph). Two-dimensional time dependent tracking of the corners (tractor front left and right, trailer rear left and right) of the vehicle was documented and an imaging of the Detroit Diesel engine electronic control module (ECM) was collected after each test. Results of this study show that above speed ranges of 48 to 56 kph (30–35 mph), the timing involved in a constant-speed lane change maneuver tends to converge toward a constant; however, at lower speeds a clear inverse relation exists between speed and lane change timing. Empirical relationships were developed to more accurately predict the lane change dynamics of multiple points and the overall profile of an articulated commercial vehicle. Overall, this study provides data and relationships for consideration in lane change dynamics as well as the ability to distinguish timing of when a tractor-trailer would become perceivable versus its position in the roadway.
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Corpus, Robert Michael, Robert James Lomotan i Peter Vasquez. "A Comparison of the Fuel Economy Estimates of a Drive Cycle Developed Using the Road Load Energy Criterion and the Actual On-Road Fuel Economy in a Private Vehicle in the Philippines". W ASME 2022 16th International Conference on Energy Sustainability collocated with the ASME 2022 Heat Transfer Summer Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/es2022-85434.
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Abstract This study presents a comparison of the fuel economy between a drive cycle developed using the road load energy as an assessment parameter and the actual on road fuel consumption of a common rail direct injection (CRDI) passenger van. Second by second velocity as well as fuel consumption were recorded as the test vehicle traverses a 33 - kilometer pre-determined route in Quezon city, Philippines. The data were processed to generate a drive cycle using the modified Markov Chain approach. A user defined compression ratio was used to determine the length of the generated drive cycle. It was then tested on a chassis dynamometer to measure the fuel economy of the drive cycle. The road load energy, fuel economy, average speed, maximum acceleration and percent idle time were used as assessment variables to determine the quality of the drive cycles developed. Three drive cycles using different compression ratios were generated and yielded the following results: A 676 second cycle which has a 2.22% road load energy error and a 4.9% difference in fuel consumption, the 801 second cycle yielded a 3.06% energy error and 2.8% fuel consumption difference and a 901 second cycle with a 1.34% energy error and a 1.2% difference in fuel consumption. The results suggest that the road load energy criterion is a parameter that can be used to generate drive cycles that will give good on-road fuel economy estimation.
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Pramstrahler, Simon, Andreas Peters, Mikel Lucas García De Albéniz, Peter Adrian Leitl, Franz Heitmeir i Andreas Marn. "The Impact of Inlet Flow Angle on Turbine Vane Frame Aerodynamic Performance". W ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/gt2022-78065.
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Abstract Modern aero-engines are designed for high efficiency and low weight to reduce fuel consumption and achieve reductions in CO2 emissions. According to the goals and roadmap of the “Flightpath 2050” report, the Strategic Research and Innovation Agenda (SRIA) demands a drastic reduction of emissions to balance further air traffic growth. Therefore, technologies and processes allowing for a 75 % reduction in CO2 emissions per passenger kilometer compared to the year 2000 technology standard must be available by 2050. Turbine Vane Frames (TVF) are one technology to increase the efficiency of aero-engines and can therefore help to reach this goal. Turbine Vane Frames are located in-between the high-pressure turbine (HPT) and the low-pressure turbine (LPT) of an aero-engine and have three major purposes: guiding the flow to higher radii, incorporating the function of stator guide vanes of the first stage of the LPT, and passing structural components and oil pipes through the flow channel. A TVF with aft-loaded wide-chord main vanes and splitter vanes was designed, which meets engine-representative mechanical and aerodynamic constraints. A test vehicle consisting of the TVF and a first-stage LPT rotor has been designed and is currently being tested in the subsonic test turbine facility for aerodynamic, aeroacoustic and aeroelastic investigations (STTF-AAAI) at the Graz University of Technology. In the engine, the TVF needs to function at high performance not only at the aerodynamic design point (cruise) but also at off-design conditions. A splittered TVF design features complex flow fields with strong secondary flow interactions, and because of the fundamental design differences, the flow field characteristics within a TVF are different from those in a conventional LPT vane row. This paper discusses the flow field in a splittered TVF with emphasis on secondary flow structures and their interaction with each other and the main flow. To examine the influence of different swirl angle levels on the flow field and loss generation mechanisms inside the TVF, the swirl angle upstream of the TVF is numerically changed in a wide range from positive to negative angles. The objective of this study is to examine the sensitivity of the splitter vanes to large flow angle deviations, as present in part-load operation. Additionally, the flow field downstream of the TVF and its influence on the LPT rotor performance is described in detail. The size and locations of separated flow regions resulting from the off-design incidence of the flow and their impact on the rotor are investigated and quantified. A loss breakdown is presented to discuss the impact of incidence variations on the performance of both the TVF and the LPT.