Real-world emissions and fuel consumption of diesel buses and trucks in Macao: From on-road measurement to policy implications

NASA Astrophysics Data System (ADS)

Wu, Xiaomeng; Zhang, Shaojun; Wu, Ye; Li, Zhenhua; Zhou, Yu; Fu, Lixin; Hao, Jiming

2015-11-01

A total of 13 diesel buses and 12 diesel trucks in Macao were tested using portable emission measurement systems (PEMS) including a SEMTECH-DS for gaseous emissions and a SEMTECH-PPMD for PM2.5. The average emission rates of gaseous pollutants and CO2 are developed with the operating mode defined by the instantaneous vehicle specific power (VSP) and vehicle speed. Both distance-based and fuel mass-based emission factors for gaseous pollutants (e.g., CO, THC and NOX) are further estimated under typical driving conditions. The average distance-based NOX emission of heavy-duty buses (HDBs) is higher than 13 g km-1. Considering the unfavorable conditions for selective reductions catalyst (SCR) systems, such as low-speed driving conditions, more effective technology options (e.g., dedicated natural gas buses and electric buses) should be considered by policy makers in Macao. We identified strong effects of the vehicle size, engine displacement and driving conditions on real-world CO2 emission factors and fuel consumption for diesel vehicles. Therefore, detailed profiles regarding vehicle specifications can reduce the uncertainty in their fleet-average on-road fuel consumption. In addition, strong correlations between relative emission factors and driving conditions indicated by the average speed of generated micro-trips are identified based on a micro-trip method. For example, distance-based emission factors of HDBs will increase by 39% for CO, 29% for THC, 43% for NOX and 26% for CO2 when the average speed decreases from 30 km h-1 to 20 km h-1. The mitigation of on-road emissions from diesel buses and trucks by improving traffic conditions through effective traffic and economic management measures is therefore required. This study demonstrates the important role of PEMS in understanding vehicle emissions and mitigation strategies from science to policy perspectives.

Alternative Fuels Data Center: Michigan Transports Students in Hybrid

Science.gov Websites

Electric School Buses Michigan Transports Students in Hybrid Electric School Buses to someone by E-mail Share Alternative Fuels Data Center: Michigan Transports Students in Hybrid Electric School Electric School Buses on Twitter Bookmark Alternative Fuels Data Center: Michigan Transports Students in

Gas Phase Emission Ratios From In-Use Diesel and CNG Curbside Passenger Buses in New York City

NASA Astrophysics Data System (ADS)

Herndon, S. C.; Shorter, J.; Canagaratna, M.; Jayne, J.; Nelson, D. D.; Wormhoudt, J. C.; Williams, P.; Silva, P. J.; Shi, Q.; Ghertner, A.; Zahniser, M.; Worsnop, D.; Kolb, C.; Lanni, T.; Drewnick, F.; Demerjian, K. L.

2002-12-01

The Aerodyne Mobile Laboratory simultaneously measured gas phase and particulate emissions from in use vehicles during two campaigns in New York City. The campaigns took place during two weeks in October, 2000 and four weeks in July-August, 2001. Passenger curbside buses were the primary focus of the study, but school buses and several other heavy duty diesel vehicles were also characterized. This paper describes the methodologies used to measure individual in use vehicles and presents the results of the gas phase measurements. Emission ratios for NO, NO2, SO2, N2O, CO, CH4 and H2CO relative to CO2 have been determined across several classes of buses. The gas phase concentrations were measured each second, using Tunable Infrared Laser Direct Absorption Spectroscopy (TILDAS). Some of the categories of buses into which the data has been sorted are; diesel (both 6V92 and Series 50) with and without the Continuous Regenerative Technology (CRT) retrofit, compressed natural gas powered(CNG) and hybrid diesel-electric buses. The New York Metropolitan Transit Authority (MTA) cooperated with this work, providing details about each of their buses followed. In addition to MTA buses, other New York City passenger bus operators were also measured. In September 2000, MTA began to switch to 30 ppm sulfur diesel fuel while it is believed the non MTA operators did not. The measured emission ratios show that low sulfur fuel greatly reduces the amount of SO2 per CO2. Roughly one third of the MTA fleet of diesel buses have been equipped with the CRT retrofit. The gas phase results of interest in this category show increased direct emission of NO2 and companion work (also submitted to the 12th CRC) show the impact the CRT refit has on particulate emissions. CNG buses show increased H2CO and CH4 emission ratios relative to diesel powered motors.

Alternative Fuels Data Center: North Carolina Airport Advances With Plug-In

Science.gov Websites

Electric BusesA> North Carolina Airport Advances With Plug-In Electric Buses to someone by E-mail passengers with plug-in hybrid electric buses. For information about this project, contact Centralina Clean . Provided by Maryland Public Television Related Videos Photo of a car Electric Vehicles Charge up at State

[Quantitative study of diesel/CNG buses exhaust particulate size distribution in a road tunnel].

PubMed

Zhu, Chun; Zhang, Xu

2010-10-01

Vehicle emission is one of main sources of fine/ultra-fine particles in many cities. This study firstly presents daily mean particle size distributions of mixed diesel/CNG buses traffic flow by 4 days consecutive real world measurement in an Australia road tunnel. Emission factors (EFs) of particle size distribution of diesel buses and CNG buses are obtained by MLR methods, particle distributions of diesel buses and CNG buses are observed as single accumulation mode and nuclei-mode separately. Particle size distributions of mixed traffic flow are decomposed by two log-normal fitting curves for each 30 min interval mean scans, the degrees of fitting between combined fitting curves and corresponding in-situ scans for totally 90 fitting scans are from 0.972 to 0.998. Finally particle size distributions of diesel buses and CNG buses are quantified by statistical whisker-box charts. For log-normal particle size distribution of diesel buses, accumulation mode diameters are 74.5-86.5 nm, geometric standard deviations are 1.88-2.05. As to log-normal particle size distribution of CNG buses, nuclei-mode diameters are 19.9-22.9 nm, geometric standard deviations are 1.27-1.3.

Circuit engineering principles for construction of bipolar large-scale integrated circuit storage devices and very large-scale main memory

NASA Astrophysics Data System (ADS)

Neklyudov, A. A.; Savenkov, V. N.; Sergeyez, A. G.

1984-06-01

Memories are improved by increasing speed or the memory volume on a single chip. The most effective means for increasing speeds in bipolar memories are current control circuits with the lowest extraction times for a specific power consumption (1/4 pJ/bit). The control current circuitry involves multistage current switches and circuits accelerating transient processes in storage elements and links. Circuit principles for the design of bipolar memories with maximum speeds for an assigned minimum of circuit topology are analyzed. Two main classes of storage with current control are considered: the ECL type and super-integrated injection type storage with data capacities of N = 1/4 and N 4/16, respectively. The circuits reduce logic voltage differentials and the volumes of lexical and discharge buses and control circuit buses. The limiting speed is determined by the antiinterference requirements of the memory in storage and extraction modes.

23 CFR 771.115 - Classes of actions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... rail, light rail, commuter rail, automated guideway transit). (4) New construction or extension of a separate roadway for buses or high occupancy vehicles not located within an existing highway facility. (b...

23 CFR 771.115 - Classes of actions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... rail, light rail, commuter rail, automated guideway transit). (4) New construction or extension of a separate roadway for buses or high occupancy vehicles not located within an existing highway facility. (b...

23 CFR 771.115 - Classes of actions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... rail, light rail, commuter rail, automated guideway transit). (4) New construction or extension of a separate roadway for buses or high occupancy vehicles not located within an existing highway facility. (b...

Particle and gaseous emissions from compressed natural gas and ultralow sulphur diesel-fuelled buses at four steady engine loads.

PubMed

Jayaratne, E R; Ristovski, Z D; Meyer, N; Morawska, L

2009-04-01

Exhaust emissions from thirteen compressed natural gas (CNG) and nine ultralow sulphur diesel in-service transport buses were monitored on a chassis dynamometer. Measurements were carried out at idle and at three steady engine loads of 25%, 50% and 100% of maximum power at a fixed speed of 60 km h(-1). Emission factors were estimated for particle mass and number, carbon dioxide and oxides of nitrogen for two types of CNG buses (Scania and MAN, compatible with Euro 2 and 3 emission standards, respectively) and two types of diesel buses (Volvo Pre-Euro/Euro1 and Mercedez OC500 Euro3). All emission factors increased with load. The median particle mass emission factor for the CNG buses was less than 1% of that from the diesel buses at all loads. However, the particle number emission factors did not show a statistically significant difference between buses operating on the two types of fuel. In this paper, for the very first time, particle number emission factors are presented at four steady state engine loads for CNG buses. Median values ranged from the order of 10(12) particles min(-)(1) at idle to 10(15) particles km(-)(1) at full power. Most of the particles observed in the CNG emissions were in the nanoparticle size range and likely to be composed of volatile organic compounds The CO2 emission factors were about 20% to 30% greater for the diesel buses over the CNG buses, while the oxides of nitrogen emission factors did not show any difference due to the large variation between buses.

Physical and Chemical Characterization of Real-World Particle Number and Mass Emissions from City Buses in Finland.

PubMed

Pirjola, Liisa; Dittrich, Aleš; Niemi, Jarkko V; Saarikoski, Sanna; Timonen, Hilkka; Kuuluvainen, Heino; Järvinen, Anssi; Kousa, Anu; Rönkkö, Topi; Hillamo, Risto

2016-01-05

Exhaust emissions of 23 individual city buses at Euro III, Euro IV and EEV (Enhanced Environmentally Friendly Vehicle) emission levels were measured by the chasing method under real-world conditions at a depot area and on the normal route of bus line 24 in Helsinki. The buses represented different technologies from the viewpoint of engines, exhaust after-treatment systems (ATS) and fuels. Some of the EEV buses were fueled by diesel, diesel-electric, ethanol (RED95) and compressed natural gas (CNG). At the depot area the emission factors were in the range of 0.3-21 × 10(14) # (kg fuel)(-1), 6-40 g (kg fuel)(-1), 0.004-0.88 g (kg fuel)(-1), 0.004-0.56 g (kg fuel)(-1), 0.01-1.2 g (kg fuel)(-1), for particle number (EFN), nitrogen oxides (EFNOx), black carbon (EFBC), organics (EFOrg), and particle mass (EFPM1), respectively. The highest particulate emissions were observed from the Euro III and Euro IV buses and the lowest from the ethanol and CNG-fueled buses, which emitted BC only during acceleration. The organics emitted from the CNG-fueled buses were clearly less oxidized compared to the other bus types. The bus line experiments showed that lowest emissions were obtained from the ethanol-fueled buses whereas large variation existed between individual buses of the same type indicating that the operating conditions by drivers had large effect on the emissions.

Evaluation of horizontal curve design

DOT National Transportation Integrated Search

1980-08-01

This report documents an initial evaluation of horizontal curve design criteria which involved two phases: an observational study and an analytical evaluation. Three classes of vehicles (automobiles, school buses and tractor semi-trailers) and three ...

Fresh and Oxidized Emissions from In-Use Transit Buses Running on Diesel, Biodiesel, and CNG.

PubMed

Watne, Ågot K; Psichoudaki, Magda; Ljungström, Evert; Le Breton, Michael; Hallquist, Mattias; Jerksjö, Martin; Fallgren, Henrik; Jutterström, Sara; Hallquist, Åsa M

2018-06-26

The potential effect of changing to a nonfossil fuel vehicle fleet was investigated by measuring primary emissions (by extractive sampling of bus plumes) and secondary mass formation, using a Gothenburg Potential Aerosol Mass (Go:PAM) reactor, from 29 in-use transit buses. Regarding fresh emissions, diesel (DSL) buses without a diesel particulate filter (DPF) emitted the highest median mass of particles, whereas compressed natural gas (CNG) buses emitted the lowest ( Md EF PM 514 and 11 mg kg fuel -1 , respectively). Rapeseed methyl ester (RME) buses showed smaller Md EF PM and particle sizes than DSL buses. DSL (no DPF) and hybrid-electric RME (RME HEV ) buses exhibited the highest particle numbers ( Md EF PN 12 × 10 14 # kg fuel -1 ). RME HEV buses displayed a significant nucleation mode ( D p < 20 nm). EF PN of CNG buses spanned the highest to lowest values measured. Low Md EF PN and Md EF PM were observed for a DPF-equipped DSL bus. Secondary particle formation resulting from exhaust aging was generally important for all the buses (79% showed an average EF PM:AGED /EF PM:FRESH ratio >10) and fuel types tested, suggesting an important nonfuel dependent source. The results suggest that the potential for forming secondary mass should be considered in future fuel shifts, since the environmental impact is different when only considering the primary emissions.

Intelligent Urban Public Transportation for Accessibility Dedicated to People with Disabilities

PubMed Central

Zhou, Haiying; Hou, Kun-Mean; Zuo, Decheng; Li, Jian

2012-01-01

The traditional urban public transport system generally cannot provide an effective access service for people with disabilities, especially for disabled, wheelchair and blind (DWB) passengers. In this paper, based on advanced information & communication technologies (ICT) and green technologies (GT) concepts, a dedicated public urban transportation service access system named Mobi+ has been introduced, which facilitates the mobility of DWB passengers. The Mobi+ project consists of three subsystems: a wireless communication subsystem, which provides the data exchange and network connection services between buses and stations in the complex urban environments; the bus subsystem, which provides the DWB class detection & bus arrival notification services; and the station subsystem, which implements the urban environmental surveillance & bus auxiliary access services. The Mobi+ card that supports multi-microcontroller multi-transceiver adopts the fault-tolerant component-based hardware architecture, in which the dedicated embedded system software, i.e., operating system micro-kernel and wireless protocol, has been integrated. The dedicated Mobi+ embedded system provides the fault-tolerant resource awareness communication and scheduling mechanism to ensure the reliability in data exchange and service provision. At present, the Mobi+ system has been implemented on the buses and stations of line ‘2’ in the city of Clermont-Ferrand (France). The experiential results show that, on one hand the Mobi+ prototype system reaches the design expectations and provides an effective urban bus access service for people with disabilities; on the other hand the Mobi+ system is easily to deploy in the buses and at bus stations thanks to its low energy consumption and small form factor. PMID:23112622

Intelligent urban public transportation for accessibility dedicated to people with disabilities.

PubMed

Zhou, Haiying; Hou, Kun-Mean; Zuo, Decheng; Li, Jian

2012-01-01

The traditional urban public transport system generally cannot provide an effective access service for people with disabilities, especially for disabled, wheelchair and blind (DWB) passengers. In this paper, based on advanced information & communication technologies (ICT) and green technologies (GT) concepts, a dedicated public urban transportation service access system named Mobi+ has been introduced, which facilitates the mobility of DWB passengers. The Mobi+ project consists of three subsystems: a wireless communication subsystem, which provides the data exchange and network connection services between buses and stations in the complex urban environments; the bus subsystem, which provides the DWB class detection & bus arrival notification services; and the station subsystem, which implements the urban environmental surveillance & bus auxiliary access services. The Mobi+ card that supports multi-microcontroller multi-transceiver adopts the fault-tolerant component-based hardware architecture, in which the dedicated embedded system software, i.e., operating system micro-kernel and wireless protocol, has been integrated. The dedicated Mobi+ embedded system provides the fault-tolerant resource awareness communication and scheduling mechanism to ensure the reliability in data exchange and service provision. At present, the Mobi+ system has been implemented on the buses and stations of line '2' in the city of Clermont-Ferrand (France). The experiential results show that, on one hand the Mobi+ prototype system reaches the design expectations and provides an effective urban bus access service for people with disabilities; on the other hand the Mobi+ system is easily to deploy in the buses and at bus stations thanks to its low energy consumption and small form factor.

Evaluating real-world CO2 and NOX emissions for public transit buses using a remote wireless on-board diagnostic (OBD) approach.

PubMed

Yang, Liuhanzi; Zhang, Shaojun; Wu, Ye; Chen, Qizheng; Niu, Tianlin; Huang, Xu; Zhang, Shida; Zhang, Liangjun; Zhou, Yu; Hao, Jiming

2016-11-01

The challenge to mitigate real-world emissions from vehicles calls for powerful in-use compliance supervision. The remote on-board diagnostic (OBD) approach, with wireless data communications, is one of the promising next-generation monitoring methods. We collected second-by-second profiles of carbon dioxide (CO 2 ) and nitrogen oxides (NO X ) emissions, driving conditions and engine performance for three conventional diesel and three hybrid diesel buses participating in a remote OBD pilot program in Nanjing, China. Our results showed that the average CO 2 emissions for conventional diesel and hybrid diesel buses were 816 ± 83 g km -1 and 627 ± 54 g km -1 , respectively, under a typical driving pattern. An operating mode binning analysis indicated that CO 2 emissions reduction by series-parallel hybrid technology was largely because of the significant benefits of the technology under the modes of low speed and low power demand. However, significantly higher CO 2 emissions were observed for conventional diesel buses during rush hours, higher than 1200 g km -1 . The OBD data suggested no improvement in NO X emission reduction for hybrid buses compared with conventional buses; both were approximately 12 g km -1 because of poor performance of the selective catalyst reduction (SCR) systems in the real world. Speed-dependent functions for real-world CO 2 and NO X emissions were also constructed. The CO 2 emissions of hybrid buses were much less sensitive to the average speed than conventional buses. If the average speed decreased from 20 km h -1 to 10 km h -1 , the estimated CO 2 emission factor for conventional buses would be increased by 34%. Such a change in speed would increase NO X emissions for conventional and hybrid buses by 38% and 56%, respectively. This paper demonstrates the useful features of the remote OBD system and can inform policy makers how to take advantage of these features in monitoring in-use vehicles. Copyright © 2016 Elsevier Ltd. All rights reserved.

Natural gas as a future fuel for heavy-duty vehicles

DOT National Transportation Integrated Search

2001-06-21

In addition to their significant environmental impacts, medium-duty and heavy-duty (HD) vehicles are high volume fuel users. Development of such vehicles, which include transit buses, refuse trucks, and HD Class 6-8 trucks, that are fueled with natur...

System Engineering Analysis of Topside Cranes Installed on AD, AR, and AS Class Ships

DTIC Science & Technology

1982-02-06

4 severity CASREPs. Water or moisture in oumzs or motors accounted for five CASREPs; moisture in a transformer caused a class C fire , which resulted...Components of Bridge Cranes, Monorail Hoist Systems, and Side Port Hoists Associated Equipment: Accumulators Ladders Speed reducers Brakes Load blocks...Switches Bridge Locking devices *Tow bars Bumpers * Monorails Tracks Collector assembly Motors (electrical *Trolley buses Controller and hydraulic) *Trolleys

Alternative Fuels Data Center: Propane Buses Shuttle Visitors in Maine

Science.gov Websites

Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles Relies on Natural Gas Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in

Alternative Fuels Data Center: Little Rock Gains Momentum with Natural Gas

Science.gov Websites

BusesA> Little Rock Gains Momentum with Natural Gas Buses to someone by E-mail Share Alternative on compressed natural gas. For information about this project, contact Arkansas Clean Cities Public Television Related Videos Photo of a car Hydrogen Powers Fuel Cell Vehicles in California Nov. 18

Improved Results for Route Planning in Stochastic Transportation Networks

NASA Technical Reports Server (NTRS)

Boyan, Justin; Mitzenmacher, Michael

2000-01-01

In the bus network problem, the goal is to generate a plan for getting from point X to point Y within a city using buses in the smallest expected time. Because bus arrival times are not determined by a fixed schedule but instead may be random. the problem requires more than standard shortest path techniques. In recent work, Datar and Ranade provide algorithms in the case where bus arrivals are assumed to be independent and exponentially distributed. We offer solutions to two important generalizations of the problem, answering open questions posed by Datar and Ranade. First, we provide a polynomial time algorithm for a much wider class of arrival distributions, namely those with increasing failure rate. This class includes not only exponential distributions but also uniform, normal, and gamma distributions. Second, in the case where bus arrival times are independent and geometric discrete random variable,. we provide an algorithm for transportation networks of buses and trains, where trains run according to a fixed schedule.

Particle and gaseous emissions from individual diesel and CNG buses

NASA Astrophysics Data System (ADS)

Hallquist, Å. M.; Jerksjö, M.; Fallgren, H.; Westerlund, J.; Sjödin, Å.

2012-10-01

In this study size-resolved particle and gaseous emissions from 28 individual diesel-fuelled and 7 compressed natural gas (CNG)-fuelled buses, selected from an in-use bus fleet, were characterised for real-world dilution scenarios. The method used was based on using CO2 as a tracer of exhaust gas dilution. The particles were sampled by using an extractive sampling method and analysed with high time resolution instrumentation EEPS (10 Hz) and CO2 with non-dispersive infrared gas analyser (LI-840, LI-COR Inc. 1 Hz). The gaseous constituents (CO, HC and NO) were measured by using a remote sensing device (AccuScan RSD 3000, Environmental System Products Inc.). Nitrogen oxides, NOx, were estimated from NO by using default NO2/NOx ratios from the road vehicle emission model HBEFA 3.1. The buses studied were diesel-fuelled Euro II-V and CNG-fuelled Enhanced Environmental Friendly Vehicles (EEVs) with different after-treatment, including selective catalytic reduction (SCR), exhaust gas recirculation (EGR) and with and without diesel particulate filter (DPF). The primary driving mode applied in this study was accelerating mode. However, regarding the particle emissions also a constant speed mode was analysed. The investigated CNG buses emitted on average higher number of particles but less mass compared to the diesel-fuelled buses. Emission factors for number of particles (EFPN) were EFPN, DPF = 8.0 ± 3.1 × 1014, EFPN, no DPF =2.8 ± 1.6 × 1015 and EFPN, CNG = 7.8 ± 5.7 × 1015 (kg fuel-1). In the accelerating mode size-resolved EFs showed unimodal number size distributions with peak diameters of 70-90 nm and 10 nm for diesel and CNG buses, respectively. For the constant speed mode bimodal average number size distributions were obtained for the diesel buses with peak modes of ~10 nm and ~60 nm. Emission factors for NOx expressed as NO2 equivalents for the diesel buses were on average 27 ± 7 g (kg fuel)-1 and for the CNG buses 41 ± 26 g (kg fuel)-1. An anti-relationship between EFNOx and EFPM was observed especially for buses with no DPF and there was a positive relationship between EFPM and EFCO.

Particle and gaseous emissions from individual diesel and CNG buses

NASA Astrophysics Data System (ADS)

Hallquist, Å. M.; Jerksjö, M.; Fallgren, H.; Westerlund, J.; Sjödin, Å.

2013-05-01

In this study size-resolved particle and gaseous emissions from 28 individual diesel-fuelled and 7 compressed natural gas (CNG)-fuelled buses, selected from an in-use bus fleet, were characterised for real-world dilution scenarios. The method used was based on using CO2 as a tracer of exhaust gas dilution. The particles were sampled by using an extractive sampling method and analysed with high time resolution instrumentation EEPS (10 Hz) and CO2 with a non-dispersive infrared gas analyser (LI-840, LI-COR Inc. 1 Hz). The gaseous constituents (CO, HC and NO) were measured by using a remote sensing device (AccuScan RSD 3000, Environmental System Products Inc.). Nitrogen oxides, NOx, were estimated from NO by using default NO2/NOx ratios from the road vehicle emission model HBEFA3.1. The buses studied were diesel-fuelled Euro III-V and CNG-fuelled Enhanced Environmentally Friendly Vehicles (EEVs) with different after-treatment, including selective catalytic reduction (SCR), exhaust gas recirculation (EGR) and with and without diesel particulate filter (DPF). The primary driving mode applied in this study was accelerating mode. However, regarding the particle emissions also a constant speed mode was analysed. The investigated CNG buses emitted on average a higher number of particles but less mass compared to the diesel-fuelled buses. Emission factors for number of particles (EFPN) were EFPN, DPF = 4.4 ± 3.5 × 1014, EFPN, no DPF = 2.1 ± 1.0 × 1015 and EFPN, CNG = 7.8 ± 5.7 ×1015 kg fuel-1. In the accelerating mode, size-resolved emission factors (EFs) showed unimodal number size distributions with peak diameters of 70-90 nm and 10 nm for diesel and CNG buses, respectively. For the constant speed mode, bimodal average number size distributions were obtained for the diesel buses with peak modes of ~10 nm and ~60 nm. Emission factors for NOx expressed as NO2 equivalents for the diesel buses were on average 27 ± 7 g (kg fuel)-1 and for the CNG buses 41 ± 26 g (kg fuel)-1. An anti-relationship between EFNOx and EFPM was observed especially for buses with no DPF, and there was a positive relationship between EFPM and EFCO.

Development of a new eyellipse and seating accommodation model for trucks and buses.

DOT National Transportation Integrated Search

2005-11-01

Driver posture data from a laboratory study and an in-vehicle test-track study were used to develop and to : evaluate a new seating accommodation model and eyellipse for SAE Class-B vehicles. The new statistical : models are configurable for populati...

School Buses & Seat Belts: A Discussion.

ERIC Educational Resources Information Center

Alaska State Dept. of Education, Juneau.

Safety belts are not installed in school buses for several reasons. School buses are constructed differently from automobiles in terms of (1) the locations of doors and instrument panels relative to passengers, (2) outer construction, (3) seat design and padding, and (4) visibility on the road. Under current regulations, bus seats are constructed…

[Volatile organic compounds concentrations and sources inside new air-conditioned bus].

PubMed

You, Ke-Wei; Ge, Yun-Shan; Qian, Yi-Xin; Liu, Wei; Feng, Bo; Zhang, Yan-Ni; Ning, Zhan-Wu; Hu, Bin; Zhao, Shou-Tang

2008-05-01

The distributing profile and concentration level inside new air-conditioned buses with 53 seats have been determined using the method of thermal desorption-capillary GC/MS under vehicle static conditions. Compounds were identified from their mass spectral data by using US National Institute of Standards and Technology (NIST02). The total numbers of identified components were 33 inside buses, including alkenes (15,45.4%), aromatic compounds (9,27.3%), alcohols (4,12.1%), ketones (3,9.1%) and esters (2,6.1%), especially in the range of C6-C10. The top 5 compounds measured inside buses were decane (8.01 mg/m3), 3-methylhexane (7.10 mg/m3), heptane (5.10 mg/m3), isoheptane (4.20 mg/m3) and 1-Methyl-3-ethylbenzene (3.56 mg/m3), and total volatile organic compounds (TVOC) > 52.5 mg/m3. The main sources of in-vehicle hydrocarbons and aromatic compounds comes from cabin components and interior trim materials (e.g., sealants, carpets, adhesives, paints, leather, plastics, PU foam and PE foam) that may retain certain VOCs during manufacturing, and/or emit these compounds over an extended period of time from off-gassing, aging-related breakdown products, heating/cooling and so on.

Fleet DNA: Commercial Fleet Vehicle Operating Data | Transportation

Science.gov Websites

and Vehicle Dynamometer Evaluation and Comparison of Class 7 Hybrid Electric and Conventional Diesel Gasoline-Electric Hybrid Transit Buses In-Use Performance Comparison of Hybrid Electric, CNG, and Diesel Diesel Electric Hybrid Tractor Evaluation: 13-Month Final Report Project Startup: Evaluating Coca-Cola's

Rapid identification of high particle number emitting on-road vehicles and its application to a large fleet of diesel buses.

PubMed

Jayaratne, E R; Morawska, L; Ristovski, Z D; He, C

2007-07-15

Pollutant concentrations measured in the exhaust plume of a vehicle may be related to the pollutant emission factor using the CO2 concentration as a measure of the dilution factor. We have used this method for the rapid identification of high particle number (PN) emitting on-road vehicles. The method was validated for PN using a medium-duty vehicle and successfully applied to measurements of PN emissions from a large fleet of on-road diesel buses. The ratio of PN concentration to CO2 concentration, Z, in the exhaust plume was estimated for individual buses. On the average, a bus emitted about 1.5 x 10(9) particles per mg of CO2 emitted. A histogram of the number of buses as a function of Z showed, for the first time, that the PN emissions from diesel buses followed a gamma distribution, with most of the values within a narrow range and a few buses exhibiting relatively large values. It was estimated that roughly 10% and 50% of the PN emissions came from just 2% and 25% of the buses, respectively. A regression analysis showed that there was a positive correlation between Z and age of buses, with the slope of the best line being significantly different from zero. The mean Z value for the pre-Euro buses was significantly greater than each of the values for the Euro I and II buses.

Alternative Fuels Data Center: Natural Gas Fuels School Buses and Refuse

Science.gov Websites

Efficiency March 8, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a school bus Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles With Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2010 CFR

2010-10-01

... control wiring must be— (1) Suitable for installation within in a switchboard enclosure and be rated at 90... 46 Shipping 4 2010-10-01 2010-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping... REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

Fuzzy usage pattern in customizing public transport fleet and its maintenance options

NASA Astrophysics Data System (ADS)

Husniah, H.; Herdiani, L.; Kusmaya; Supriatna, A. K.

2018-05-01

In this paper we study a two-dimensional maintenance contract for a fleet of public transport, such as buses, shuttle etc. The buses are sold with a two-dimensional warranty. The warranty and the maintenance contract are characterized by two parameters – age and usage – which define a two-dimensional region. However, we use one dimensional approach to model these age and usage of the buses. The under-laying maintenance service contracts is the one which offers policy limit cost to protect a service provider (an agent) from over claim and to pursue the owner to do maintenance under specified cost in house. This in turn gives benefit for both the owner of the buses and the agent of service contract. The decision problem for an agent is to determine the optimal price for each option offered, and for the owner is to select the best contract option. We use a Nash game theory formulation in order to obtain a win-win solution – i.e. the optimal price for the agent and the optimal option for the owner. We further assume that there will be three different usage pattern of the buses, i.e. low, medium, and high pattern of the usage rate. In many situations it is often that we face a blur boundary between the adjacent patterns. In this paper we look for the optimal price for the agent and the optimal option for the owner, which minimizes the expected total cost while considering the fuzziness of the usage rate pattern.

49 CFR 604.13 - Registration of private charter operators.

Code of Federal Regulations, 2011 CFR

2011-10-01

... provider: (1) Company name, address, phone number, e-mail address, and facsimile number; (2) Federal and, if available, state motor carrier identifying number; (3) The geographic service areas of public... intends to provide charter service; (4) The number of buses or vans the private charter operator owns; (5...

49 CFR 604.13 - Registration of private charter operators.

Code of Federal Regulations, 2013 CFR

2013-10-01

... provider: (1) Company name, address, phone number, e-mail address, and facsimile number; (2) Federal and, if available, state motor carrier identifying number; (3) The geographic service areas of public... intends to provide charter service; (4) The number of buses or vans the private charter operator owns; (5...

49 CFR 604.13 - Registration of private charter operators.

Code of Federal Regulations, 2014 CFR

2014-10-01

... provider: (1) Company name, address, phone number, e-mail address, and facsimile number; (2) Federal and, if available, state motor carrier identifying number; (3) The geographic service areas of public... intends to provide charter service; (4) The number of buses or vans the private charter operator owns; (5...

49 CFR 604.13 - Registration of private charter operators.

Code of Federal Regulations, 2012 CFR

2012-10-01

... provider: (1) Company name, address, phone number, e-mail address, and facsimile number; (2) Federal and, if available, state motor carrier identifying number; (3) The geographic service areas of public... intends to provide charter service; (4) The number of buses or vans the private charter operator owns; (5...

Alternative Fuels Data Center: Propane Powers School Buses in Tuscaloosa,

Science.gov Websites

Efficiency March 8, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a school bus and Plug-In Electric Vehicles March 31, 2012 Natural Gas School Buses Help Kansas City Save Money Nov Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Electric Trolley Boosts Business in

Alternative Fuels Data Center: Recycled Cooking Oil Powers Biodiesel

Science.gov Websites

Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of the front of a red truck Salt Lake City Buses Help Kansas City Save Money Nov. 12, 2011 Electric Trucks Deliver at Kansas City Schools Sept. 17 Electric Buses Aug. 21, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010

On-road pollutant emission and fuel consumption characteristics of buses in Beijing.

PubMed

Wang, Aijuan; Ge, Yunshan; Tan, Jianwei; Fu, Mingliang; Shah, Asad Naeem; Ding, Yan; Zhao, Hong; Liang, Bin

2011-01-01

On-road emission and fuel consumption (FC) levels for Euro III and IV buses fueled on diesel and compressed natural gas (CNG) were compared, and emission and FC characteristics of buses were analyzed based on approximately 28,700 groups of instantaneous data obtained in Beijing using a portable emissions measurement system (PEMS). The experimental results revealed that NOx and PM emissions from CNG buses were decreased by 72.0% and 82.3% respectively, compared with Euro IV diesel buses. Similarly, these emissions were reduced by 75.2% and 96.3% respectively, compared with Euro III diesel buses. In addition, CO2, CO, HC, NOx, PM emissions and FC of Euro IV diesel buses were reduced by 26.4%, 75.2%, 73.6%, 11.4%, 79.1%, and 26.0%, respectively, relative to Euro III diesel buses. The CO2, CO, HC, NOx, PM emissions and FC factors all decreased with bus speed increased, while increased as bus acceleration increased. At the same time, the emission/FC rates as well as the emission/FC factors exhibited a strong positive correlation with the vehicle specific power (VSP). They all were the lowest when VSP < 0, and then rapidly increased as VSP increased. Furthermore, both the emission/FC rates and emission/FC factors were the highest at accelerations, higher at cruise speeds, and the lowest at decelerations for non-idling buses. These results can provide a base reference to further estimate bus emission and FC inventories in Beijing.

On-road measurement of regulated pollutants from diesel and CNG buses with urea selective catalytic reduction systems

NASA Astrophysics Data System (ADS)

Guo, Jiadong; Ge, Yunshan; Hao, Lijun; Tan, Jianwei; Li, Jiaqiang; Feng, Xiangyu

2014-12-01

In this study, emissions from 13 buses operated in Beijing, including two Euro-III diesel buses, four Euro-IV diesel buses, three Euro-V diesel buses and four Euro-V CNG buses, were characterized in real world conditions. All of the buses tested were fitted with selective catalytic reduction (SCR) systems except for the Euro-III diesel buses. A SEMTECH-DS was used for testing the gaseous pollutants, and an electric low pressure impactor (ELPI) was used for measuring of particle numbers and size distributions. A comparison was made based on emission performance of these buses by employing the VSP approach and fuel- based emissions factors. Diesel buses emitted less CO and THC but more NOx and PM pollutants than CNG buses. The NOx reduction efficiencies of the SCR systems for CNG buses were higher because of the high exhaust temperature and high NO2/NOx ratio, whereas the efficiencies for diesel buses were lower. This resulted in extremely low NOx emissions from CNG buses, but the high NO2/NOx ratio needs further study. Failures of urea injection in the SCR systems were detected in this research, which resulted in very high NOx emissions. The CNG buses also emitted smaller numbers of particles and less particle mass with the presence of oxidation catalysts. Diesel buses satisfying the Euro-V standard performed better than Euro-IV and Euro-III diesel buses in terms of emission performance, except for more nuclei mode particles. Most of time, the Euro-IV diesel buses show no advantages in CO and NOx emissions compared with the Euro-III diesel buses.

Medium- and Heavy-Duty Vehicle Duty Cycles for Electric Powertrains

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelly, Kenneth; Bennion, Kevin; Miller, Eric

2016-03-02

NREL's Fleet Test and Evaluation group has extensive in-use vehicle data demonstrating the importance of understanding the vocational duty cycle for appropriate sizing of electric vehicle (EV) and power electronics components for medium- and heavy-duty EV applications. This presentation includes an overview of recent EV fleet evaluation projects that have valuable in-use data that can be leveraged for sub-system research, analysis, and validation. Peak power and power distribution data from in-field EVs are presented for four different vocations, including class 3 delivery vans, class 6 delivery trucks, class 8 transit buses, and class 8 port drayage trucks, demonstrating the impactsmore » of duty cycle on performance requirements.« less

COMPARISON OF CLEAN DIESEL BUSES TO CNG BUSES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowell, D.; Parsley, W.; Bush,C

2003-08-24

Using previously published data on regulated and unregulated emissions, this paper will compare the environmental performance of current generation transit buses operated on compressed natural gas (CNG) to current generation transit buses operated on ultra low sulfur diesel fuel (ULSD) and incorporating diesel particulate filters (DPF). Unregulated emissions evaluated include toxic compounds associated with adverse health effects (carbonyl, PAH, NPAH, benzene) as well as PM particle count and size distribution. For all regulated and unregulated emissions, both technologies are shown to be comparable. DPF equipped diesel buses and CNG buses have virtually identical levels of PM mass emissions and particlemore » number emissions. DPF-equipped diesel buses have lower HC and CO emissions and lower emissions of toxic substances such as benzene, carbonyls and PAHs than CNG buses. CNG buses have lower NOx emissions than DPF-equipped buses, though CNG bus NOx emissions are shown to be much more variable. In addition, this paper will compare the capital and operating costs of CNG and DPF-equipped buses. The cost comparison is primarily based on the experience of MTA New York City Transit in operating CNG buses since 1995 and DPF-equipped buses fueled with ULSD since 2001. Published data on the experience of other large transit agencies in operating CNG buses is used to validate the NYCT experience. The incremental cost (compared to ''baseline'' diesel) of operating a typical 200-bus depot is shown to be six times higher for CNG buses than for ''clean diesel'' buses. The contributors to this increased cost for CNG buses are almost equally split between increased capital costs for purchase of buses and installation of fueling infrastructure, and increased operating costs for purchase of fuel, bus maintenance, and fuel station maintenance.« less

Efficient and Robust Data Collection Using Compact Micro Hardware, Distributed Bus Architectures and Optimizing Software

NASA Technical Reports Server (NTRS)

Chau, Savio; Vatan, Farrokh; Randolph, Vincent; Baroth, Edmund C.

2006-01-01

Future In-Space propulsion systems for exploration programs will invariably require data collection from a large number of sensors. Consider the sensors needed for monitoring several vehicle systems states of health, including the collection of structural health data, over a large area. This would include the fuel tanks, habitat structure, and science containment of systems required for Lunar, Mars, or deep space exploration. Such a system would consist of several hundred or even thousands of sensors. Conventional avionics system design will require these sensors to be connected to a few Remote Health Units (RHU), which are connected to robust, micro flight computers through a serial bus. This results in a large mass of cabling and unacceptable weight. This paper first gives a survey of several techniques that may reduce the cabling mass for sensors. These techniques can be categorized into four classes: power line communication, serial sensor buses, compound serial buses, and wireless network. The power line communication approach uses the power line to carry both power and data, so that the conventional data lines can be eliminated. The serial sensor bus approach reduces most of the cabling by connecting all the sensors with a single (or redundant) serial bus. Many standard buses for industrial control and sensor buses can support several hundreds of nodes, however, have not been space qualified. Conventional avionics serial buses such as the Mil-Std-1553B bus and IEEE 1394a are space qualified but can support only a limited number of nodes. The third approach is to combine avionics buses to increase their addressability. The reliability, EMI/EMC, and flight qualification issues of wireless networks have to be addressed. Several wireless networks such as the IEEE 802.11 and Ultra Wide Band are surveyed in this paper. The placement of sensors can also affect cable mass. Excessive sensors increase the number of cables unnecessarily. Insufficient number of sensors may not provide adequate coverage of the system. This paper also discusses an optimal technique to place and validate sensors.

Ultrafine particle concentrations in and around idling school buses

NASA Astrophysics Data System (ADS)

Zhang, Qunfang; Fischer, Heidi J.; Weiss, Robert E.; Zhu, Yifang

2013-04-01

Unnecessary school bus idling increases children's exposure to diesel exhaust, but to what extent children are exposed to ultrafine particles (UFPs, diameter < 100 nm) in and around idling school buses remains unclear. This study employed nine school buses and simulated five scenarios by varying emissions source, wind direction, and window position. The purpose was to investigate the impact of idling on UFP number concentration and PM2.5 mass concentration inside and near school buses. Near the school buses, total particle number concentration increased sharply from engine off to engine on under all scenarios, by a factor of up to 26. The impact of idling on UFP number concentration inside the school buses depended on wind direction and window position: wind direction was important and statistically significant while the effect of window positions depended on wind direction. Under certain scenarios, idling increased in-cabin total particle number concentrations by a factor of up to 5.8, with the significant increase occurring in the size range of 10-30 nm. No significant change of in-cabin PM2.5 mass concentration was observed due to idling, regardless of wind direction and window position, indicating that PM2.5 is not a good indicator for primary diesel exhaust particle exposure. The deposition rates based on total particle number concentration inside school bus cabins varied between 1.5 and 5.0 h-1 across nine tested buses under natural convection conditions, lower than those of passenger cars but higher than those of indoor environments.

Renewable Fuels and Lubricants Laboratory | Transportation Research | NREL

Science.gov Websites

delivery vans to full-size buses and Class 8 tractors. Heavy-Duty and Light-Duty Engine Dynamometer Test Cells The ReFUEL Laboratory features two engine dynamometer test cells-one for heavy-duty (up to 600 hp the Heavy-Duty Federal Test Procedures (HD-FTP), are highly standardized, and results can be readily

40 CFR 86.004-15 - NOX plus NMHC and particulate averaging, trading, and banking for heavy-duty engines.

Code of Federal Regulations, 2013 CFR

2013-07-01

... all diesel-cycle engine families within the same primary service class is allowed. (ii) Urban buses... averaging set from all other heavy-duty engines. Averaging and trading between diesel cycle bus engine... heavy-duty engines, the equivalent mileage is 6.3 miles. For diesel heavy-duty engines, the equivalent...

40 CFR 86.004-15 - NOX plus NMHC and particulate averaging, trading, and banking for heavy-duty engines.

Code of Federal Regulations, 2014 CFR

2014-07-01

... all diesel-cycle engine families within the same primary service class is allowed. (ii) Urban buses... averaging set from all other heavy-duty engines. Averaging and trading between diesel cycle bus engine... heavy-duty engines, the equivalent mileage is 6.3 miles. For diesel heavy-duty engines, the equivalent...

78 FR 17749 - Parts and Accessories Necessary for Safe Operation; Exemption Renewal for Greyhound Lines, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-22

... placement of video event recorders at the top of the windshields on its buses. Greyhound may continue to use the video event recorders to increase safety through (1) Identification and remediation of risky... applied for an exemption from 49 CFR 393.60(e)(1) to allow it to install video event [[Page 17750...

Air quality and climate impacts of alternative bus technologies in Greater London.

PubMed

Chong, Uven; Yim, Steve H L; Barrett, Steven R H; Boies, Adam M

2014-04-15

The environmental impact of diesel-fueled buses can potentially be reduced by the adoption of alternative propulsion technologies such as lean-burn compressed natural gas (LB-CNG) or hybrid electric buses (HEB), and emissions control strategies such as a continuously regenerating trap (CRT), exhaust gas recirculation (EGR), or selective catalytic reduction with trap (SCRT). This study assessed the environmental costs and benefits of these bus technologies in Greater London relative to the existing fleet and characterized emissions changes due to alternative technologies. We found a >30% increase in CO2 equivalent (CO2e) emissions for CNG buses, a <5% change for exhaust treatment scenarios, and a 13% (90% confidence interval 3.8-20.9%) reduction for HEB relative to baseline CO2e emissions. A multiscale regional chemistry-transport model quantified the impact of alternative bus technologies on air quality, which was then related to premature mortality risk. We found the largest decrease in population exposure (about 83%) to particulate matter (PM2.5) occurred with LB-CNG buses. Monetized environmental and investment costs relative to the baseline gave estimated net present cost of LB-CNG or HEB conversion to be $187 million ($73 million to $301 million) or $36 million ($-25 million to $102 million), respectively, while EGR or SCRT estimated net present costs were $19 million ($7 million to $32 million) or $15 million ($8 million to $23 million), respectively.

Interior noise profile of buses in Curitiba

NASA Astrophysics Data System (ADS)

Zannin, Paulo H. T.; Giovanini, Clifton R.; Diniz, Fabiano B.; Ferreira, Jose C.

2002-11-01

Evaluating the noise levels to which the bus drivers of Curitiba are exposed to during their working days is the main scope of this study. The city is served by an internationally known public transportation system featuring 1902 buses, which attend 1.9 million people per day. Two measurements have been taken inside each one of the 60 buses surveyed, one close to the driver and another one at the back of the bus. The results have showed that the dose levels the drivers are exposed to were below 50% in 92% out of the buses, but the normalized exposure levels were over 65 dB(A) in all cases. This level is considered as the threshold of comfort according to the Brazilian legislation on occupancy health NR-17--Ergonomics. The surveyed buses have been divided into three categories, according to their characteristics: feeder, rapid, and bi-articulated. A total of 20 buses within each category have been surveyed. Among the different categories, it has been found that the feeders have presented the highest noise levels. (To be presented in Portuguese.)

A comparative investigation of ultrafine particle number and mass emissions from a fleet of on-road diesel and CNG buses.

PubMed

Jayaratne, E R; He, C; Ristovski, Z D; Morawska, L; Johnson, G R

2008-09-01

Particle number, particle mass, and CO2 concentrations were measured on the curb of a busy urban busway used entirely by a mix of diesel and CNG operated buses. With the passage of each bus, the ratio of particle number concentration and particle mass concentration to CO2 concentration in the diluted exhaust plume were used as measures of the particle number and mass emission factors, respectively. With all buses accelerating pastthe monitoring point, the results showed that the median particle mass emission from CNG buses was less than 9% of that from diesel buses. However, the median particle number emission from CNG buses was 6 times higher than the diesel buses, and the particles from the CNG buses were mainly in the nanoparticle size range. Using a thermodenuder to remove the volatile material from the sampled emissions showed that the majority of particles from the CNG buses, but not from the diesel buses, were volatile. Approximately, 82% of the particles from the CNG buses and 38% from the diesel buses were removed by heating the emissions to 300 degrees C.

The challenge to NOx emission control for heavy-duty diesel vehicles in China

NASA Astrophysics Data System (ADS)

Wu, Y.; Zhang, S. J.; Li, M. L.; Ge, Y. S.; Shu, J. W.; Zhou, Y.; Xu, Y. Y.; Hu, J. N.; Liu, H.; Fu, L. X.; He, K. B.; Hao, J. M.

2012-07-01

China's new "Twelfth Five-Year Plan" set a target for total NOx emission reduction of 10% for the period of 2011-2015. Heavy-duty diesel vehicles (HDDVs) have been considered a major contributor to NOx emissions in China. Beijing initiated a comprehensive vehicle test program in 2008. This program included a sub-task for measuring on-road emission profiles of hundreds of HDDVs using portable emission measurement systems (PEMS). The major finding is that neither the on-road distance-specific (g km -1) nor brake-specific (g kW h-1) NOx emission factors for diesel buses and heavy-duty diesel trucks improved in most cases as emission standards became more stringent. For example, the average NOx emission factors for Euro II, Euro III and Euro IV buses are 11.3±3.3 g km-1, 12.5± 1.3 g km-1, and 11.8±2.0 g km-1, respectively. No statistically significant difference in NOx emission factors was observed between Euro II and III buses. Even for Euro IV buses equipped with SCR systems, the NOx emission factors are similar to Euro III buses. The data regarding real-time engine performance of Euro IV buses suggest the engine certification cycles did not reflect their real-world operating conditions. These new on-road test results indicate that previous estimates of total NOx emissions for HDDV fleet may be significantly underestimated. The new estimate in total NOx emissions for the Beijing HDDV fleet in 2009 is 37.0 Gg, an increase of 45% compared to the previous study. Further, we estimate that the total NOx emissions for the national HDDV fleet in 2009 are approximately 4.0 Tg, higher by 1.0 Tg (equivalent to 18% of total NOx emissions for vehicle fleet in 2009) than that estimated in the official report. This would also result in 4% increase in estimation of national anthropogenic NOx emissions. More effective control measures (such as promotion of CNG buses and a new in-use compliance testing program) are urged to secure the goal of total NOxmitigation for the HDDV fleet in the future.

The challenge to NOx emission control for heavy-duty diesel vehicles in China

NASA Astrophysics Data System (ADS)

Wu, Y.; Zhang, S. J.; Li, M. L.; Ge, Y. S.; Shu, J. W.; Zhou, Y.; Xu, Y. Y.; Hu, J. N.; Liu, H.; Fu, L. X.; He, K. B.; Hao, J. M.

2012-10-01

China's new "Twelfth Five-Year Plan" set a target for total NOx emission reduction of 10% for the period of 2011-2015. Heavy-duty diesel vehicles (HDDVs) have been considered a major contributor to NOx emissions in China. Beijing initiated a comprehensive vehicle test program in 2008. This program included a sub-task for measuring on-road emission profiles of hundreds of HDDVs using portable emission measurement systems (PEMS). The major finding is that neither the on-road distance-specific (g km-1) nor brake-specific (g kWh-1) NOx emission factors for diesel buses and heavy-duty diesel trucks improved in most cases as emission standards became more stringent. For example, the average NOx emission factors for Euro II, Euro III and Euro IV buses are 11.3 ± 3.3 g km-1, 12.5 ± 1.3 g km-1, and 11.8 ± 2.0 g km-1, respectively. No statistically significant difference in NOx emission factors was observed between Euro II and III buses. Even for Euro IV buses equipped with SCR systems, the NOx emission factors are similar to Euro III buses. The data regarding real-time engine performance of Euro IV buses suggest the engine certification cycles did not reflect their real-world operating conditions. These new on-road test results indicate that previous estimates of total NOx emissions for HDDV fleet may be significantly underestimated. The new estimate in total NOx emissions for the Beijing HDDV fleet in 2009 is 37.0 Gg, an increase of 45% compared to the previous study. Further, we estimate that the total NOx emissions for the national HDDV fleet in 2009 are approximately 4.0 Tg, higher by 1.0 Tg (equivalent to 18% of total NOx emissions for vehicle fleet in 2009) than that estimated in the official report. This would also result in 4% increase in estimation of national anthropogenic NOx emissions. More effective control measures (such as promotion of CNG buses and a new in-use compliance testing program) are urged to secure the goal of total NOx mitigation for the HDDV fleet in the future.

Alternative Fuels Data Center: Glacier-Waterton Park Powers Buses With

Science.gov Websites

Photo of a truck Natural Gas Fuels School Buses and Refuse Trucks in Tulsa, Oklahoma Feb. 18, 2017 Photo of buses Baton Rouge School District Adds Propane Buses to Its Fleet Dec. 23, 2016 photo of a truck Buses to Its Fleet Nov. 11, 2016 photo of a propane school bus Propane Powers School Buses in Tuscaloosa

Alternative Fuels Data Center: Virginia Transportation Data for Alternative

Science.gov Websites

://www.youtube.com/embed/1S7JJHQpc1w Video thumbnail for Propane Buses Save Money for Virginia Schools Propane Buses Save Money for Virginia Schools Feb. 25, 2010 https://www.youtube.com/embed/enxaQ_QooWE Chart Data

Buses retrofitting with diesel particle filters: Real-world fuel economy and roadworthiness test considerations.

PubMed

Fleischman, Rafael; Amiel, Ran; Czerwinski, Jan; Mayer, Andreas; Tartakovsky, Leonid

2018-05-01

Retrofitting older vehicles with diesel particulate filter (DPF) is a cost-effective measure to quickly and efficiently reduce particulate matter emissions. This study experimentally analyzes real-world performance of buses retrofitted with CRT DPFs. 18 in-use Euro III technology urban and intercity buses were investigated for a period of 12months. The influence of the DPF and of the vehicle natural aging on buses fuel economy are analyzed and discussed. While the effect of natural deterioration is about 1.2%-1.3%, DPF contribution to fuel economy penalty is found to be 0.6% to 1.8%, depending on the bus type. DPF filtration efficiency is analyzed throughout the study and found to be in average 96% in the size range of 23-560nm. Four different load and non-load engine operating modes are investigated on their appropriateness for roadworthiness tests. High idle is found to be the most suitable regime for PN diagnostics considering particle number filtration efficiency. Copyright © 2017. Published by Elsevier B.V.

Crashworthiness of Small Poststandard School Buses: Safety Study.

ERIC Educational Resources Information Center

National Transportation Safety Board (DOT), Washington, DC.

In 1977, a series of Federal Motor Vehicle Safety Standards (FMVSS) for school buses became effective, mandating different performance standards for school buses compared to other buses. Because data on the crash performance of school buses built to these standards were lacking, the National Transportation Safety Board conducted a series of…

Measurement and comparison of Bangkok diesel bus emissions and performance using on-board equipment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burnette, A.D.; Kishan, S.; Wangwongwatana, S.

1997-12-31

An on-board measurement system was assembled and used to compare the emissions and performance of buses in Bangkok, Thailand under actual driving conditions. Three similar buses were compared: one using an engine without special emissions control design, one with an engine meeting Euro 1 standards, and one with an engine meeting Euro 2 standards. As the buses drove their routes, second-by-second data were collected for engine rpm, throttle position, vehicle speed, exhaust concentrations of hydrocarbons, carbon monoxide, carbon dioxide, oxygen, nitric oxide, and exhaust opacity. Vehicle performance data were calculated using algorithms developed during previous driving studies in Bangkok. Grammore » per liter of fuel used emission factors were developed for gaseous pollutants using combustion calculations and these were translated into gram per kilometer traveled emission factors using the fuel efficiency data for the buses. Smoke data were left in terms of opacity. Test results are designed to be used to compare the cost benefit of upgrading buses with no emissions controls to Euro 1 or Euro 2 technologies. Ongoing tests will help bus companies determine the benefit of incremental improvements to bus engines and other emissions reduction strategies.« less

Chemical and toxicological properties of emissions from CNG transit buses equipped with three-way catalysts compared to lean-burn engines and oxidation catalyst technologies

NASA Astrophysics Data System (ADS)

Yoon, Seungju; Hu, Shaohua; Kado, Norman Y.; Thiruvengadam, Arvind; Collins, John F.; Gautam, Mridul; Herner, Jorn D.; Ayala, Alberto

2014-02-01

Chemical and toxicological properties of emissions from compressed natural gas (CNG) fueled transit buses with stoichiometric combustion engines and three-way catalyst (TWC) exhaust control systems were measured using a chassis dynamometer testing facility and compared to the data from earlier CNG engine and exhaust control technologies. Gaseous and particulate matter emissions from buses with stoichiometric engines and TWC were significantly lower than the emissions from buses with lean-burn engines. Carbonyls and volatile organic compounds (VOCs) from buses with stoichiometric engines and TWC were lower by more than 99% compared to buses with lean-burn engines. Elemental and organic carbons (EC and OC), polycyclic aromatic hydrocarbons (PAHs), and trace elements from buses with stoichiometric engines and TWC were effectively controlled and significantly lower than the emissions from buses with lean-burn engines. Potential mutagenicity measured using a microsuspension modification of the Salmonella/microsome assay was lower by more than 99% for buses with stoichiometric engines and TWC, compared to buses with lean-burn engines and OxC.

Characterizing ultrafine particles and other air pollutants in and around school buses.

PubMed

Zhu, Yifang; Zhang, Qunfang

2014-03-01

Increasing evidence has demonstrated toxic effects of ultrafine particles (UFP*, diameter < 100 nm). Children are particularly at risk because of their immature respiratory systems and higher breathing rates per body mass. This study aimed to characterize UFP, PM2.5 (particulate matter < or = 2.5 microm in aerodynamic diameter), and other vehicular-emitted pollutants in and around school buses. Four sub-studies were conducted, including: 1. On-road tests to measure in-cabin air pollutant levels while school buses were being driven; 2. Idling tests to determine the contributions of tailpipe emissions from idling school buses to air pollutant levels in and around school buses under different scenarios; 3. Retrofit tests to evaluate the performance of two retrofit systems, a diesel oxidation catalyst (DOC) muffler and a crankcase filtration system (CFS), on reducing tailpipe emissions and in-cabin air pollutant concentrations under idling and driving conditions; and 4. High efficiency particulate air (HEPA) filter air purifier tests to evaluate the effectiveness of in-cabin filtration. In total, 24 school buses were employed to cover a wide range of school buses commonly used in the United States. Real-time air quality measurements included particle number concentration (PNC), fine and UFP size distribution in the size range 7.6-289 nm, PM2.5 mass concentration, black carbon (BC) concentration, and carbon monoxide (CO) and carbon dioxide (CO2) concentrations. For in-cabin measurements, instruments were placed on a platform secured to the rear seats inside the school buses. For all other tests, a second set of instruments was deployed to simultaneously measure the ambient air pollutant levels. For tailpipe emission measurements, the exhaust was diluted and then measured by instruments identical to those used for the in-cabin measurements. The results show that when driving on roads, in-cabin PNC, fine and UFP size distribution, PM2.5, BC, and CO varied by engine age, window position, driving speed, driving route, and operating conditions. Emissions from idling school buses increased the PNC close to the tailpipe by a factor of up to 26.0. Under some circumstances, tailpipe emissions of idling school buses increased the in-cabin PNC by factors ranging from 1.2 to 5.8 in the 10-30 nm particle size range. Retrofit systems significantly reduced the tailpipe emissions of idling school buses. With both DOC and CFS installed, PNC in tailpipe emissions dropped by 20%-94%. No unequivocal decrease was observed for in-cabin air pollutants after retrofitting. The operation of the air conditioning (AC) unit and the pollutant concentrations in the surrounding ambient air played more important roles than retrofit technologies in determining in-cabin air quality. The use of a HEPA air purifier removed up to 50% of in-cabin particles. Because each sub-study tested only a subset of the 24 school buses, the results should be seen as more exploratory than definitive.

Measuring self-pollution in school buses using a tracer gas technique

NASA Astrophysics Data System (ADS)

Behrentz, Eduardo; Fitz, Dennis R.; Pankratz, David V.; Sabin, Lisa D.; Colome, Steven D.; Fruin, Scott A.; Winer, Arthur M.

A potentially important, but inadequately studied, source of children's exposure to pollutants during school bus commutes is the introduction of a bus's own exhaust into the passenger compartment. We developed and applied a method to determine the amount of a bus's own exhaust penetrating into the cabin in a study of six in-use school buses over a range of routes, roadway types, fuels, and emission control technologies. A tracer gas, SF 6, was metered into the bus's exhaust system using a mass flow controller whose flow rate was logged by a data acquisition system and processed with the concurrent real-time pollutant measurement data. At the same time, the SF 6 concentration inside the bus was measured using an AeroVironment CTA-1000 continuous analyzer connected to a series of solenoids that switched the sample inlet between the front and rear of the bus cabin. To account for a baseline drift of the CTA-1000, SF 6-free air was also drawn through a line located outside at the front of the bus. Although this third sample line generally provided a reference zero value, it also showed that under certain wind conditions (i.e., wind from the rear) when the bus was stopped and was idling, significant amounts of the bus's own exhaust reached this location at the front of the bus. Self-pollution, the percentage of a bus's own exhaust that can be found inside its cabin, was a function of bus type and age, and a strong function of window position (i.e., open or closed). We estimated up to 0.3% of the air inside the cabin was from the bus's own exhaust in older buses, approximately 10 times the percentage observed for newer buses, and 25% of the black carbon concentration variance was explained by the buses' self-pollution. Analysis of the tracer gas concentrations provided a powerful tool for identifying potentially high-exposure conditions.

Assessment on the occupational exposure of urban public bus drivers to bioaccessible trace metals through resuspended fraction of settled bus dust.

PubMed

Gao, Peng; Liu, Sa; Ye, Wenyuan; Lin, Nan; Meng, Ping; Feng, Yujie; Zhang, Zhaohan; Cui, Fuyi; Lu, Binyu; Xing, Baoshan

2015-03-01

Limited information is available on the bioaccessible fraction of trace metals in the resuspended fraction of settled bus dust in order to estimate bus drivers' occupational exposure. In this study, 45 resuspended fraction of settled dust samples were collected from gasoline and compressed natural gas (CNG) powered buses and analyzed for trace metals and their fraction concentrations using a three-step sequential extraction procedure. Experimental results showed that zinc (Zn) had the greatest bioaccessible fraction, recorded as an average of 608.53 mg/kg, followed in order of decreasing concentration by 129.80 mg/kg lead (Pb), 56.77 mg/kg copper (Cu), 34.03 mg/kg chromium (Cr), 22.05 mg/kg nickel (Ni), 13.17 mg/kg arsenic (As) and 2.77 mg/kg cadmium (Cd). Among the three settled bus dust exposure pathways, ingestion was the main route. Total exposure hazard index (HIt) for non-carcinogenic effect trace metals was lower than the safety level of 1. The incremental lifetime cancer risk (ILCR) for drivers was estimated for trace metal exposure. Pb and Ni presented relatively high potential risks in the non-carcinogenic and potentially carcinogenic health assessment for all drivers. ILCR was in the range of 1.84E-05 to 7.37E-05 and 1.74E-05 to 6.95E-05 for gasoline and CNG buses, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

Effects of Hydrogen Peroxide on Common Aviation Textiles

DTIC Science & Technology

2009-08-01

efficacious (complete kill of 106 CFU of the spore forming Geobacillus stearothermophilus ) in a narrow-body aircraft fuselage (3), as well as wide-body...disinfectant/ sterilant for transportation vehicles like aircraft, buses, subway trains, ambulances, etc. Although the biological efficacy of STERIS...hydrogen peroxide (VHP)1 technology is of particular interest due to rapid sterilization , easy usage, intrinsic environmental friendliness (i .e

Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses : Evaluation Results Update

DOT National Transportation Integrated Search

2007-10-01

In early 2007, the National Renewable Energy Laboratory (NREL) published a preliminary evaluation results report1 (April through November 2006) on hydrogen fuel cell and diesel buses operating at Alameda-Contra Costa Transit District (AC Transit) in ...

Cost-benefit analysis of safety belts in Texas school buses.

PubMed

Begley, C E; Biddle, A K

1988-01-01

Although safety belts have been shown to reduce the risk of serious injury or death in automobile crashes, evidence of their effectiveness in school buses is uncertain. In this paper, the potential costs and benefits of mandatory safety belts in Texas school buses are estimated, based on the assumption that their effectiveness is less than or equal to rear seatbelt effectiveness in autos. Costs are based on both retrofitting old buses with belts and installing them in new buses. Benefits include the direct and indirect (forgone earnings) cost-savings from preventable injuries and fatalities. Results indicate that a law mandating safety belts in Texas school buses would not be cost-beneficial. Annual benefits would exceed the annual costs of installing belts in new school buses. However, the benefits would not be large enough to compensate for the five-year costs associated with retrofitting old buses.

Cost-benefit analysis of safety belts in Texas school buses.

PubMed Central

Begley, C E; Biddle, A K

1988-01-01

Although safety belts have been shown to reduce the risk of serious injury or death in automobile crashes, evidence of their effectiveness in school buses is uncertain. In this paper, the potential costs and benefits of mandatory safety belts in Texas school buses are estimated, based on the assumption that their effectiveness is less than or equal to rear seatbelt effectiveness in autos. Costs are based on both retrofitting old buses with belts and installing them in new buses. Benefits include the direct and indirect (forgone earnings) cost-savings from preventable injuries and fatalities. Results indicate that a law mandating safety belts in Texas school buses would not be cost-beneficial. Annual benefits would exceed the annual costs of installing belts in new school buses. However, the benefits would not be large enough to compensate for the five-year costs associated with retrofitting old buses. PMID:3140273

Alternative Fuels Data Center: South Florida Furnishing Retailer Relies on

Science.gov Websites

Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010

Alternative Fuels Data Center: Natural Gas Powers Milk Delivery Trucks in

Science.gov Websites

Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at a charging station Companies Power School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles Relies on Natural Gas Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in

Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandler, K.; Eudy, L.

2007-03-01

This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

Analysis of transportation network design strategies for forced transfer busing.

DOT National Transportation Integrated Search

2009-12-01

Forced transfer busing occurs primarily at the elementary school level when students are bused : to an alternate school when their geographically-assigned school is full at their specific grade : level. Ineffective forced transfer busing can result i...

Carbon Dioxide Concentrations and Temperatures within Tour Buses under Real-Time Traffic Conditions.

PubMed

Chiu, Chun-Fu; Chen, Ming-Hung; Chang, Feng-Hsiang

2015-01-01

This study monitored the carbon dioxide (CO2) concentrations and temperatures of three 43-seat tour buses with high-passenger capacities in a course of a three-day, two-night school excursion. Results showed that both driver zones and passenger zones of the tour buses achieved maximum CO2 concentrations of more than 3000 ppm, and maximum daily average concentrations of 2510.6 and 2646.9 ppm, respectively. The findings confirmed that the CO2 concentrations detected in the tour buses exceeded the indoor air quality standard of Taiwan Environmental Protection Administration (8 hr-CO2: 1000 ppm) and the air quality guideline of Hong Kong Environmental Protection Department (1 hr-CO2: 2500 ppm for Level 1 for buses). Observations also showed that high-capacity tour bus cabins with air conditioning system operating in recirculation mode are severely lacking in air exchange rate, which may negatively impact transportation safety. Moreover, the passenger zones were able to maintain a temperature of between 20 and 25°C during travel, which effectively suppresses the dispersion of volatile organic compounds. Finally, the authors suggest that in the journey, increasing the ventilation frequency of tour bus cabin, which is very beneficial to maintain the travel safety and enhance the quality of travel.

Carbon Dioxide Concentrations and Temperatures within Tour Buses under Real-Time Traffic Conditions

PubMed Central

Chiu, Chun-Fu; Chen, Ming-Hung; Chang, Feng-Hsiang

2015-01-01

This study monitored the carbon dioxide (CO2) concentrations and temperatures of three 43-seat tour buses with high-passenger capacities in a course of a three-day, two-night school excursion. Results showed that both driver zones and passenger zones of the tour buses achieved maximum CO2 concentrations of more than 3000 ppm, and maximum daily average concentrations of 2510.6 and 2646.9 ppm, respectively. The findings confirmed that the CO2 concentrations detected in the tour buses exceeded the indoor air quality standard of Taiwan Environmental Protection Administration (8 hr-CO2: 1000 ppm) and the air quality guideline of Hong Kong Environmental Protection Department (1 hr-CO2: 2500 ppm for Level 1 for buses). Observations also showed that high-capacity tour bus cabins with air conditioning system operating in recirculation mode are severely lacking in air exchange rate, which may negatively impact transportation safety. Moreover, the passenger zones were able to maintain a temperature of between 20 and 25°C during travel, which effectively suppresses the dispersion of volatile organic compounds. Finally, the authors suggest that in the journey, increasing the ventilation frequency of tour bus cabin, which is very beneficial to maintain the travel safety and enhance the quality of travel. PMID:25923722

Real-time measurements of nitrogen oxide emissions from in-use New York City transit buses using a chase vehicle.

PubMed

Shorter, Joanne H; Herndon, Scott; Zahniser, Mark S; Nelson, David D; Wormhoudt, Joda; Demerjian, Kenneth L; Kolb, Charles E

2005-10-15

New diesel engine technologies and alternative fuel engines are being introduced into fleets of mass transit buses to try to meet stricter emission regulations of nitrogen oxides and particulates: Real-time instruments including an Aerodyne Research tunable infrared laser differential absorption spectrometer (TILDAS) were deployed in a mobile laboratory to assess the impact of the implementation of the new technologies on nitrogen oxide emissions in real world driving conditions. Using a "chase" vehicle sampling strategy, the mobile laboratory followed target vehicles, repeatedly sampling their exhaust. Nitrogen oxides from approximately 170 in-use New York City mass transit buses were sampled during the field campaigns. Emissions from conventional diesel buses, diesel buses with continuously regenerating technology (CRT), diesel hybrid electric buses, and compressed natural gas (CNG) buses were compared. The chase vehicle sampling method yields real world emissions that can be included in more realistic emission inventories. The NO, emissions from the diesel and CNG buses were comparable. The hybrid electric buses had approximately one-half the NOx emissions. In CRT diesels, NO2 accounts for about one-third of the NOx emitted in the exhaust, while for non-CRT buses the NO2 fraction is less than 10%.

An Evaluation of a Museum Science Education Project with Social Integration and Urban Environmental Problems as a Focus.

ERIC Educational Resources Information Center

Allen, David W.

The Paired School Science Project (PSSP) conducted between public and parochial schools was evaluated over a period from 1968-71. A pilot program was carried out among fifth and sixth grade students of 30 schools in the 1967-68 school year. During the study period, these classes of the paired schools were bused to the Franklin Institute for…

Fuels for urban transit buses: a cost-effectiveness analysis.

PubMed

Cohen, Joshua T; Hammitt, James K; Levy, Jonathan I

2003-04-15

Public transit agencies have begun to adopt alternative propulsion technologies to reduce urban transit bus emissions associated with conventional diesel (CD) engines. Among the most popular alternatives are emission controlled diesel buses (ECD), defined here to be buses with continuously regenerating diesel particle filters burning low-sulfur diesel fuel, and buses burning compressed natural gas (CNG). This study uses a series of simplifying assumptions to arrive at first-order estimates for the incremental cost-effectiveness (CE) of ECD and CNG relative to CD. The CE ratio numerator reflects acquisition and operating costs. The denominator reflects health losses (mortality and morbidity) due to primary particulate matter (PM), secondary PM, and ozone exposure, measured as quality adjusted life years (QALYs). We find that CNG provides larger health benefits than does ECD (nine vs six QALYs annually per 1000 buses) but that ECD is more cost-effective than CNG (dollar 270 000 per QALY for ECD vs dollar 1.7 million to dollar 2.4 million for CNG). These estimates are subject to much uncertainty. We identify assumptions that contribute most to this uncertainty and propose potential research directions to refine our estimates.

Alternative Fuels Data Center: Corporate Fleets Set the Pace for a Green

Science.gov Websites

, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at a Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010

Alternative Fuels Data Center: Idle-Reduction Efforts Cut Emissions and

Science.gov Websites

Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at a charging station Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Relies on Natural Gas Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in

Alternative Fuels Data Center: Salt Lake City Fuels Vehicles With Natural

Science.gov Websites

Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Airport Relies on Natural Gas Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides

The Effects of School Desegregation on Minority Group Student Achievement and Self-Concept: An Evaluation of Court Ordered Busing in Waco, Texas. Final Report.

ERIC Educational Resources Information Center

Felice, Lawrence G.

The purpose of this study is to evaluate the effects of busing on the subsequent achievement performance of bused minority students. Differences in achievement gains are hypothesized to be a function of bused student attitudes toward busing and the interracial climate of acceptance in the receiving schools. The design of this study is that of a…

A Feeder-Bus Dispatch Planning Model for Emergency Evacuation in Urban Rail Transit Corridors

PubMed Central

Wang, Yun; Yan, Xuedong; Zhou, Yu; Zhang, Wenyi

2016-01-01

The mobility of modern metropolises strongly relies on urban rail transit (URT) systems, and such a heavy dependence causes that even minor service interruptions would make the URT systems unsustainable. This study aims at optimally dispatching the ground feeder-bus to coordinate with the urban rails’ operation for eliminating the effect of unexpected service interruptions in URT corridors. A feeder-bus dispatch planning model was proposed for the collaborative optimization of URT and feeder-bus cooperation under emergency situations and minimizing the total evacuation cost of the feeder-buses. To solve the model, a concept of dummy feeder-bus system is proposed to transform the non-linear model into traditional linear programming (ILP) model, i.e., traditional transportation problem. The case study of Line #2 of Nanjing URT in China was adopted to illustrate the model application and sensitivity analyses of the key variables. The modeling results show that as the evacuation time window increases, the total evacuation cost as well as the number of dispatched feeder-buses decrease, and the dispatched feeder-buses need operate for more times along the feeder-bus line. The number of dispatched feeder-buses does not show an obvious change with the increase of parking spot capacity and time window, indicating that simply increasing the parking spot capacity would cause huge waste for the emergent bus utilization. When the unbalanced evacuation demand exists between stations, the more feeder-buses are needed. The method of this study will contribute to improving transportation emergency management and resource allocation for URT systems. PMID:27676179

Special Issue Busing. NCRIEEO Newsletter, Volume 3, Number 2, May 1972.

ERIC Educational Resources Information Center

Gordon, Edmund W., Ed.

Contents of this issue of the NCRIEEO Newsletter include the following articles: (1) "Editor's commentary: background to the issue," by Edmund Gordon, which puts busing into perspective as an important educational resource--like physical facilities, instructional materials, and teachers--to be used to achieve educational and social…

Microbial air quality in mass transport buses and work-related illness among bus drivers of Bangkok Mass Transit Authority.

PubMed

Luksamijarulkul, Pipat; Sundhiyodhin, Viboonsri; Luksamijarulkul, Soavalug; Kaewboonchoo, Orawan

2004-06-01

The air quality in mass transport buses, especially air-conditioned buses may affect bus drivers who work full time. Bus numbers 16, 63, 67 and 166 of the Seventh Bus Zone of Bangkok Mass Transit Authority were randomly selected to investigate for microbial air quality. Nine air-conditioned buses and 2-4 open-air buses for each number of the bus (36 air-conditioned buses and 12 open-air buses) were included. Five points of in-bus air samples in each studied bus were collected by using the Millipore A ir Tester Totally, 180 and 60 air samples collected from air-conditioned buses and open-air buses were cultured for bacterial and fungal counts. The bus drivers who drove the studied buses were interviewed towards histories of work-related illness while working. The results revealed that the mean +/- SD of bacterial counts in the studied open-air buses ranged from 358.50 +/- 146.66 CFU/m3 to 506 +/- 137.62 CFU/m3; bus number 16 had the highest level. As well as the mean +/- SD of fungal counts which ranged from 93.33 +/- 44.83 CFU/m3 to 302 +/- 294.65 CFU/m3; bus number 166 had the highest level. Whereas, the mean +/- SD of bacterial counts in the studied air-conditioned buses ranged from 115.24 +/- 136.01 CFU/m3 to 244.69 +/- 234.85 CFU/m3; bus numbers 16 and 67 had the highest level. As well as the mean +/- SD of fungal counts which rangedfrom 18.84 +/- 39.42 CFU/m3 to 96.13 +/- 234.76 CFU/m3; bus number 166 had the highest level. When 180 and 60 studied air samples were analyzed in detail, it was found that 33.33% of the air samples from open-air buses and 6.11% of air samples from air-conditioned buses had a high level of bacterial counts (> 500 CFU/m3) while 6.67% of air samples from open-air buses and 2.78% of air samples from air-conditioned buses had a high level of fungal counts (> 500 CFU/m3). Data from the history of work-related illnesses among the studied bus drivers showed that 91.67% of open-air bus drivers and 57.28% of air-conditioned bus drivers had symptoms of work-related illnesses, p = 0.0185.

Low-floor bus design preferences of walking aid users during simulated boarding and alighting.

PubMed

D'souza, Clive; Paquet, Victor; Lenker, James; Steinfeld, Edward; Bareria, Piyush

2012-01-01

Low-floor buses represent a significant improvement in accessible public transit for passengers with limited mobility. However, there is still a need for research on the inclusive design of transit buses to identify specific low-floor bus design conditions that are either particularly accommodating or challenging for passengers with functional and mobility impairments. These include doorway locations, seating configuration and the large front wheel-well covers that collectively impact boarding, alighting and interior movement of passengers. Findings from a laboratory study using a static full-scale simulation of a lowfloor bus to evaluate the impact of seating configuration and crowding on interior movement and accessibility for individuals with and without walking aids are presented (n=41). Simulated bus journeys that included boarding, fare payment, seating, and alighting were performed. Results from video observations and subjective assessments showed differences in boarding and alighting performance and users' perceptions of task difficulty. The need for assistive design features (e.g. handholds, stanchions), legroom and stowage space for walking aids was evident. These results demonstrate that specific design conditions in low-floor buses can significantly impact design preference among those who use walking aids. Consideration of ergonomics and inclusive design can therefore be used to improve the design of low-floor buses.

System data communication structures for active-control transport aircraft, volume 1

NASA Technical Reports Server (NTRS)

Hopkins, A. L.; Martin, J. H.; Brock, L. D.; Jansson, D. G.; Serben, S.; Smith, T. B.; Hanley, L. D.

1981-01-01

Candidate data communication techniques are identified, including dedicated links, local buses, broadcast buses, multiplex buses, and mesh networks. The design methodology for mesh networks is then discussed, including network topology and node architecture. Several concepts of power distribution are reviewed, including current limiting and mesh networks for power. The technology issues of packaging, transmission media, and lightning are addressed, and, finally, the analysis tools developed to aid in the communication design process are described. There are special tools to analyze the reliability and connectivity of networks and more general reliability analysis tools for all types of systems.

Influence of public transport in black carbon

NASA Astrophysics Data System (ADS)

Vasquez, Y.; Oyola, P.; Gramsch, E. V.; Moreno, F.; Rubio, M.

2013-05-01

As a consequence of poor air quality in Santiago de Chile, several measures were taken by the local authorities to improve the environmental conditions and protect the public health. In year 2005 the Chilean government implemented a project called "Transantiago" aimed to introduce major modifications in the public transportation system. The primary objectives of this project were to: provide an economically, socially and environmentally sustainable service and improve the quality of service without increasing fares. In this work we evaluate the impact of the Transantiago system on the black carbon pollution along four roads directly affected by the modification to the transport system. The black carbon has been used to evaluate changes in air quality due to changes in traffic. The assessment was done using measurements of black carbon before Transantiago (June-July 2005) and after its implementation (June-July 2007). Four sites were selected to monitor black carbon at street levels, one site (Alameda) that represents trunk-bus streets, i.e., buses crossing the city through main avenues. Buses using these streets had an important technological update with respect to 2005. Two streets (Usach and Departamental) show a mixed condition, i.e., they combine feeder and trunk buses. These streets combine new EURO III buses with old buses with more than 3 years of service. The last street (Eliodoro Yañez) represent private cars road without public transportation and did not experience change. Hence, the results from the years 2005 and 2007 can be directly compared using an appropriate methodology. To ensure that it was not the meteorological conditions that drive the trends, the comparison between year 2005 and 2007 was done using Wilcoxon test and a regression model. A first assessment at the four sites suggested a non decrease in black carbon concentration from 2005 to 2007, except for Alameda. A first statistical approach confirmed small increases in BC in Usach and E. Yañez, a decrease in Alameda and no change in Departamental. The small increases in BC in some streets, and the decrease observed in an avenue dominated by public transportation, suggest that the reason of the increase in BC concentration is related to the increment in the total number of vehicles (diesel and non diesel). The lower number of buses or improved bus technology did not have an effect on BC concentrations. The three streets that increased or maintained the BC concentration had higher number of vehicles in 2007. Alameda Avenue showed a decrease in BC concentration that had to do with a lower total number of vehicles as well as improved bus technology in year 2007 than year 2005. The emissions, related exclusively to public transportation, seem to have diminished after the Transantiago implementation, considering the outcome in the observed BC in Alameda, mainly dominated by the public transport network. These results are an indication that in order to decrease pollution near a street is not enough to reduce the number of buses or improve its quality, but to reduce the total number of vehicles.

Bus industry market study. Report -- Task 3.2: Fuel cell/battery powered bus system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zalbowitz, M.

1992-06-02

In support of the commercialization of fuel cells for transportation, Georgetown University, as a part of the DOE/DOT Fuel Cell Transit Bus Program, conducted a market study to determine the inventory of passenger buses in service as of December, 1991, the number of buses delivered in 1991 and an estimate of the number of buses to be delivered in 1992. Short term and long term market projections of deliveries were also made. Data was collected according to type of bus and the field was divided into the following categories which are defined in the report: transit buses, school buses, commercialmore » non-transit buses, and intercity buses. The findings of this study presented with various tables of data collected from identified sources as well as narrative analysis based upon interviews conducted during the survey.« less

Clean School Bus USA: Tomorrow's Buses for Today's Children

ERIC Educational Resources Information Center

US Environmental Protection Agency, 2010

2010-01-01

The U.S. Environmental Protection Agency (EPA) is ensuring that all new buses meet tighter standards developed to reduce diesel emissions and improve safety. Today's new buses are cleaner--60 times cleaner than buses built before 1990--and feature additional emergency exits, improved mirror systems, and pedestrian safety devices. But replacing…

In-vehicle measurement of ultrafine particles on compressed natural gas, conventional diesel, and oxidation-catalyst diesel heavy-duty transit buses.

PubMed

Hammond, Davyda; Jones, Steven; Lalor, Melinda

2007-02-01

Many metropolitan transit authorities are considering upgrading transit bus fleets to decrease ambient criteria pollutant levels. Advancements in engine and fuel technology have lead to a generation of lower-emission buses in a variety of fuel types. Dynamometer tests show substantial reductions in particulate mass emissions for younger buses (<10 years) over older models, but particle number reduction has not been verified in the research. Recent studies suggest that particle number is a more important factor than particle mass in determining health effects. In-vehicle particle number concentration measurements on conventional diesel, oxidation-catalyst diesel and compressed natural gas transit buses are compared to estimate relative in-vehicle particulate exposures. Two primary consistencies are observed from the data: the CNG buses have average particle count concentrations near the average concentrations for the oxidation-catalyst diesel buses, and the conventional diesel buses have average particle count concentrations approximately three to four times greater than the CNG buses. Particle number concentrations are also noticeably affected by bus idling behavior and ventilation options, such as, window position and air conditioning.

Safety Study--Crashworthiness of Large Poststandard Schoolbuses.

ERIC Educational Resources Information Center

National Transportation Safety Board (DOT), Washington, DC.

This study reports on the crash performance of large poststandard school buses (school buses manufactured after April 1, 1977, and weighing more than 10,000 pounds unloaded) in 43 accidents investigated by the National Transportation Safety Board. The report discusses the Safety Board's findings as to how well the standards are working to protect…

Alternative Fuels Data Center: California School District Creates

Science.gov Websites

vehicle charging stations. Rental Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money School Buses Help Kansas City Save Money Nov. 12, 2011 Electric Trucks Deliver at Kansas City Schools on Natural Gas Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in

For Your Bookshelf.

ERIC Educational Resources Information Center

Jones, Rebecca

2002-01-01

Reviews notable education books of 2001: "Not in Front of the Children" (Marjorie Heins); "The other Boston Busing Story" (Susan E. Eaton); "Another Planet" (Elinor Burkett); "Parents Under Siege" (James Garbarino and Claire Bedard); "Radical Equations" (Robert P. Moses and Charles E. Cobb, Jr.); "School" (Sheila Curran Bernard and Sarah Mondale);…

49 CFR 579.22 - Reporting requirements for manufacturers of 100 or more buses, manufacturers of 500 or more...

Code of Federal Regulations, 2010 CFR

2010-10-01

...-heavy vehicles (other than buses and emergency vehicles) annually. 579.22 Section 579.22 Transportation... buses, manufacturers of 500 or more emergency vehicles and manufacturers of 5,000 or more medium-heavy... whose aggregate number of medium-heavy vehicles (a sum that does not include buses or emergency vehicles...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2010 CFR

2010-10-01

... manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles... fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles... vehicles, medium-heavy vehicles and buses, motorcycles, or trailers submitted pursuant to §§ 579.21 through...

Definition, analysis and development of an optical data distribution network for integrated avionics and control systems

NASA Technical Reports Server (NTRS)

Burns, R. R.

1981-01-01

The potential and functional requirements of fiber optic bus designs for next generation aircraft are assessed. State-of-the-art component evaluations and projections were used in the system study. Complex networks were decomposed into dedicated structures, star buses, and serial buses for detailed analysis. Comparisons of dedicated links, star buses, and serial buses with and without full duplex operation and with considerations for terminal to terminal communication requirements were obtained. This baseline was then used to consider potential extensions of busing methods to include wavelength multiplexing and optical switches. Example buses were illustrated for various areas of the aircraft as potential starting points for more detail analysis as the platform becomes definitized.

Electric vehicles in China: emissions and health impacts.

PubMed

Ji, Shuguang; Cherry, Christopher R; J Bechle, Matthew; Wu, Ye; Marshall, Julian D

2012-02-21

E-bikes in China are the single largest adoption of alternative fuel vehicles in history, with more than 100 million e-bikes purchased in the past decade and vehicle ownership about 2× larger for e-bikes as for conventional cars; e-car sales, too, are rapidly growing. We compare emissions (CO(2), PM(2.5), NO(X), HC) and environmental health impacts (primary PM(2.5)) from the use of conventional vehicles (CVs) and electric vehicles (EVs) in 34 major cities in China. CO(2) emissions (g km(-1)) vary and are an order of magnitude greater for e-cars (135-274) and CVs (150-180) than for e-bikes (14-27). PM(2.5) emission factors generally are lower for CVs (gasoline or diesel) than comparable EVs. However, intake fraction is often greater for CVs than for EVs because combustion emissions are generally closer to population centers for CVs (tailpipe emissions) than for EVs (power plant emissions). For most cities, the net result is that primary PM(2.5) environmental health impacts per passenger-km are greater for e-cars than for gasoline cars (3.6× on average), lower than for diesel cars (2.5× on average), and equal to diesel buses. In contrast, e-bikes yield lower environmental health impacts per passenger-km than the three CVs investigated: gasoline cars (2×), diesel cars (10×), and diesel buses (5×). Our findings highlight the importance of considering exposures, and especially the proximity of emissions to people, when evaluating environmental health impacts for EVs.

Detroit Commuter Hydrogen Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brooks, Jerry; Prebo, Brendan

2010-07-31

This project was undertaken to demonstrate the viability of using hydrogen as a fuel in an internal combustion engine vehicle for use as a part of a mass transit system. The advantages of hydrogen as a fuel include renew-ability, minimal environmental impact on air quality and the environment, and potential to reduce dependence on foreign energy sources for the transportation sector. Recognizing the potential for the hydrogen fuel concept, the Southeast Michigan Congress of Governments (SEMCOG) determined to consider it in the study of a proposed regional mass transit rail system for southeast Michigan. SEMCOG wanted to evaluate the feasibilitymore » of using hydrogen fueled internal combustion engine (H2ICE) vehicles in shuttle buses to connect the Detroit Metro Airport to a proposed, nearby rail station. Shuttle buses are in current use on the airport for passenger parking and inter-terminal transport. This duty cycle is well suited to the application of hydrogen fuel at this time because of the ability to re-fuel vehicles at a single nearby facility, overcoming the challenge of restricted fuel availability in the undeveloped hydrogen fuel infrastructure. A cooperative agreement between SEMCOG and the DOE was initiated and two H2ICE buses were placed in regular passenger service on March 29, 2009 and operated for six months in regular passenger service. The buses were developed and built by the Ford Motor Company. Wayne County Airport Authority provided the location for the demonstration with the airport transportation contractor, Metro Cars Inc. operating the buses. The buses were built on Ford E450 chassis and incorporated a modified a 6.8L V-10 engine with specially designed supercharger, fuel rails and injectors among other sophisticated control systems. Up to 30 kg of on-board gaseous hydrogen were stored in a modular six tank, 350 bar (5000 psi) system to provide a 150 mile driving range. The bus chassis and body were configured to carry nine passengers with luggage. By collecting fuel use data for the two H2ICE buses, with both written driver logs and onboard telemetry devices, and for two conventional propane-gasoline powered buses in the same service, comparisons of operating efficiency and maintenance requirements were completed. Public opinion about the concept of hydrogen fuel was sampled with a rider survey throughout the demonstration. The demonstration was very effective in adding to the understanding of the application of hydrogen as a transportation fuel. The two 9 passenger H2ICE buses accumulated nearly 50,000 miles and carried 14,285 passengers. Data indicated the H2ICE bus fuel economy to be 9.4 miles/ gallon of gasoline equivalent (m/GGE) compared to the 10 passenger propane-gasoline bus average of 9.8 m/GGE over 32,400 miles. The 23- passenger bus averaged 7.4 m/GGE over 40,700 miles. Rider feedback from 1050 on-board survey cards was overwhelmingly positive with 99.6% indicating they would ride again on a hydrogen powered vehicle. Minimal maintenance was required for theses buses during the demonstration project, but a longer duration demonstration would be required to more adequately assess this aspect of the concept.« less

A Universal Portable Appliance for Stellarator W7-X Power Supply Controlling

NASA Astrophysics Data System (ADS)

Xu, Wei-hua; Wolfgang, Foerster; Guenter, Mueller

2001-06-01

In the project Wendelstein 7-X (W7-X), the popular fieldbus Profibus has been determined as a uniform connection between the central control system and all the subordinate systems. A universal embedded control system has been developed for W7-X power supply controlling. Siemens 80C167CR microcontroller is used as the central control unit of the system. With a user-defined printed circuit board (PCB) several control buses, i.e., Profibus, CAN, IEEE 488, RS485 and RS 232 have been connected to the microcontroller. The corresponding hardware interfaces for the control buses have been designed. A graphic liquid crystal display(LCD) and a user-defined keyboard are used as user interface. The control software will be developed with a C-like language, i.e., C166 for the controller.

Alternative Fuels Data Center: School Buses Go Green in Virginia

Science.gov Websites

Gloucester County Public Schools put five Blue Bird propane school buses on the road. Funds from EPA and VDEQ October 2009 to November 2010, the five buses saved almost $7,000 in fuel and maintenance costs and could see, touch, and ride propane buses. And now, Gloucester's success is helping to make the case for

Perspectives on Busing. Inequality in Education, Number Eleven, March 1972.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Center for Law and Education.

Contents of this issue of "Inequality in Education" include: (1) "Busing is not the issue," Reubin Askew, Governor of Florida; (2) "Pupil transportation: a brief history," Paul V. Smith; (3) "White parents' fears," Patricia Derian, which discusses the desegregation of the schools in Jackson, Mississippi in the late 1960's from the point of view of…

Here's Just the Best, Most Complete, and (Would You Believe) Interesting Story About School Transportation Ever

ERIC Educational Resources Information Center

American School Board Journal, 1972

1972-01-01

A special study of school bus transportation that (1) describes board responsibility for bus transportation (2) discusses the merits of buying, leasing, or contracting for buses; (3) points out the inadequacy of State safety requirements; and (4) presents the merits of L.P.-gas powered and diesel powered buses. (JF)

Alternative Fuels Data Center: Alternative Fuel Vehicles Lower Emissions in

Science.gov Websites

improve air quality and save money. For information about this project, contact Clean Fuels Ohio. Download Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010

Alternative Fuels Data Center: Cities Clean up With Biofuels

Science.gov Websites

. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at Charging Stations Spread Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In

Alternative Fuels Data Center: Indiana Sanitation Department Plans to

Science.gov Websites

Money With Propane Vans Feb. 1, 2014 Photo of a school bus Michigan Transports Students in Hybrid Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In

Alternative Fuels Data Center: Hydrogen Powers Fuel Cell Vehicles in

Science.gov Websites

. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Gas Street Sweepers Improve Air Quality in New York March 11, 2010 Propane Buses Save Money for

Alternative Fuels Data Center: North Carolina City Expands Alternative Fuel

Science.gov Websites

Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In

Alternative Fuels Data Center: Electric Trucks Deliver at Kansas City

Science.gov Websites

vehicle charging stations. Rental Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks

Alternative Fuels Data Center: Virginia Converts Vehicles to Propane in

Science.gov Websites

. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Texas Taxis Go Hybrid May 6, 2010

Alternative Fuels Data Center: Pennsylvania School Buses Run on Natural Gas

Science.gov Websites

reduce petroleum use and save money. For information about this project, contact Eastern Pennsylvania Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a school bus Michigan Transports Students Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels

Using Task Clarification, Goal Setting, and Feedback to Decrease Table Busing Times in a Franchise Pizza Restaurant

ERIC Educational Resources Information Center

Amigo, Seth; Smith, Andrew; Ludwig, Timothy

2008-01-01

The current study investigated the effects of task-clarification, and manager verbal and graphic feedback on employee busing times at a pizza restaurant. Using an ABC design, task-clarification was provided in a memo, which described the process, priority, and goal time of busing. The busing time decreased slightly, from an average of 315 seconds…

Alternative Fuels Data Center: Florida Schools First in State to Power up

Science.gov Websites

Indian River County School District became the first in the state to adopt propane-powered school buses Oil Powers Biodiesel Vehicles in Vermont March 4, 2017 Photo of a truck Natural Gas Fuels School Buses Natural Gas Jan. 14, 2017 Photo of buses Baton Rouge School District Adds Propane Buses to Its Fleet Dec

Busing: Who's Being Taken for a Ride. ERIC-IRCD Urban Disadvantaged Series, Number 27, June 1972.

ERIC Educational Resources Information Center

Mills, Nicolaus

As the history and statistics of busing indicate, the greatest demand for it has come from rural states, where population is scattered and the consolidated school district is typical. But urban and suburban areas have begun to use busing more heavily than before. Not only has busing become a safety factor in crowded urban areas or suburbs where no…

Influence of diesel fuel sulfur on nanoparticle emissions from city buses.

PubMed

Ristovski, Z D; Jayaratne, E R; Lim, M; Ayoko, G A; Morawska, L

2006-02-15

Particle emissions from twelve buses, operating alternately on low sulfur (LS; 500 ppm) and ultralow sulfur (ULS; 50 ppm) diesel fuel, were monitored. The buses were 1-19 years old and had no after-treatment devices fitted. Measurements were carried out at four steady-state operational modes on a chassis dynamometer using a mini dilution tunnel (PM mass measurement) and a Dekati ejector diluter as a secondary diluter (SMPS particle number). The mean particle number emission rate (s(-1)) of the buses, in the size range 8-400 nm, using ULS diesel was 31% to 59% lower than the rate using LS diesel in all four modes. The fractional reduction was highest in the newest buses and decreased with mileage upto about 500,000 km, after which no further decrease was apparent. However, the mean total suspended particle (TSP) mass emission rate did not show a systematic difference between the two fuel types. When the fuel was changed from LS to ULS diesel, the reduction in particle number was mainly in the nanoparticle size range. Over all operational modes, 58% of the particles were smaller than 50 nm with LS fuel as opposed to just 45% with ULS fuel, suggesting that sulfur in diesel fuel was playing a major role in the formation of nanoparticles. The greatest influence of the fuel sulfur content was observed at the highest engine load, where 74% of the particles were smaller than 50 nm with LS diesel compared to 43% with ULS diesel.

Truck Traffic Iowa : 2010

DOT National Transportation Integrated Search

2011-01-01

Truck volumes represented on this map are Annual Average Daily Traffic Volumes between major traffic generators: i.e., Highway Junctions and Cities. : Truck volumes include 6-Tire and 3 Axle single unit trucks, buses and all multiple unit trucks.

Concentrations of volatile organic compounds, carbon monoxide, carbon dioxide and particulate matter in buses on highways in Taiwan

NASA Astrophysics Data System (ADS)

Hsu, Der-Jen; Huang, Hsiao-Lin

2009-12-01

Although airborne pollutants in urban buses have been studied in many cities globally, long-distance buses running mainly on highways have not been addressed in this regard. This study investigates the levels of volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO 2) and particulate matter (PM) in the long-distance buses in Taiwan. Analytical results indicate that pollutants levels in long-distance buses are generally lower than those in urban buses. This finding is attributable to the driving speed and patterns of long-distance buses, as well as the meteorological and geographical features of the highway surroundings. The levels of benzene, toluene, ethylbenzene and xylene (BTEX) found in bus cabins exceed the proposed indoor VOC guidelines for aromatic compounds, and are likely attributable to the interior trim in the cabins. The overall average CO level is 2.3 ppm, with higher average level on local streets (2.9 ppm) than on highways (2.2 ppm). The average CO 2 level is 1493 ppm, which is higher than the guideline for non-industrial occupied settings. The average PM level in this study is lower than those in urban buses and IAQ guidelines set by Taiwan EPA. However, the average PM 10 and PM 2.5 is higher than the level set by WHO. Besides the probable causes mentioned above, fewer passenger movements and less particle re-suspension from bus floor might also cause the lower PM levels. Measurements of particle size distribution reveal that more than 75% of particles are in submicron and smaller sizes. These particles may come from the infiltration from the outdoor air. This study concludes that air exchange rates in long-distance buses should be increased in order to reduce CO 2 levels. Future research on long-distance buses should focus on the emission of VOCs from brand new buses, and the sources of submicron particles in bus cabins.

Comparison of on-road emissions for hybrid and regular transit buses.

PubMed

Hallmark, Shauna L; Wang, Bo; Sperry, Robert

2013-10-01

Hybrid technology offers an attractive option for transit buses, since it has the potential to significantly reduce operating costs for transit agencies. The main impetus behind use of hybrid transit vehicles is fuel savings and reduced emissions. Laboratory tests have indicated that hybrid transit buses can have significantly lower emissions compared with conventional transit buses. However the number of studies is limited and laboratory tests may not represent actual driving conditions, since in-use vehicle operation differs from laboratory test cycles. This paper describes an on-road evaluation of in-use emission differences between hybrid-electric and conventional transit buses for the Ames, Iowa transit authority, CyRide. Emissions were collected on-road using a portable emissions monitoring system (PEMS) for three hybrid and two control buses. Emissions were collected for at least one operating bus day. Each bus was evaluated over the same route pattern, which utilizes the same driver. The number of passengers embarking or disembarking at each stop was collected by an on-board data collector so that passenger load could be included. Vehicle emissions are correlated to engine load demand, which is a function of factors such as vehicle load, speed, and acceleration. PEMS data are provided second by second and vehicle-specific power (VSP) was calculated for each row of data. Instantaneous data were stratified into the defined VSP bins and then average modal emission rates and standard errors were calculated for each bus for each pollutant. Pollutants were then compared by bus type. Carbon dioxide, carbon monoxide, and hydrocarbon emissions were higher for the regular buses across most VSP bins than for the hybrid buses. Nitrogen oxide emissions were unexpectedly higher for the hybrid buses than for the control buses.

Vibration Tests on Transit Buses

DOT National Transportation Integrated Search

1979-03-01

The objective of this vibration measurement program was to quantify the vibration environment which would be experienced by Automatic Vehicle Monitoring (AVM) equipment when installed on buses during typical city route service operations. Two buses w...

Robust planning of dynamic wireless charging infrastructure for battery electric buses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Zhaocai; Song, Ziqi

Battery electric buses with zero tailpipe emissions have great potential in improving environmental sustainability and livability of urban areas. However, the problems of high cost and limited range associated with on-board batteries have substantially limited the popularity of battery electric buses. The technology of dynamic wireless power transfer (DWPT), which provides bus operators with the ability to charge buses while in motion, may be able to effectively alleviate the drawbacks of electric buses. In this paper, we address the problem of simultaneously selecting the optimal location of the DWPT facilities and designing the optimal battery sizes of electric buses formore » a DWPT electric bus system. The problem is first constructed as a deterministic model in which the uncertainty of energy consumption and travel time of electric buses is neglected. The methodology of robust optimization (RO) is then adopted to address the uncertainty of energy consumption and travel time. The affinely adjustable robust counterpart (AARC) of the deterministic model is developed, and its equivalent tractable mathematical programming is derived. Both the deterministic model and the robust model are demonstrated with a real-world bus system. The results of our study demonstrate that the proposed deterministic model can effectively determine the allocation of DWPT facilities and the battery sizes of electric buses for a DWPT electric bus system; and the robust model can further provide optimal designs that are robust against the uncertainty of energy consumption and travel time for electric buses.« less

Predicting Airborne Particle Levels Aboard Washington State School Buses

PubMed Central

Adar, Sara D.; Davey, Mark; Sullivan, James R.; Compher, Michael; Szpiro, Adam; Liu, L.-J. Sally

2008-01-01

School buses contribute substantially to childhood air pollution exposures yet they are rarely quantified in epidemiology studies. This paper characterizes fine particulate matter (PM2.5) aboard school buses as part of a larger study examining the respiratory health impacts of emission-reducing retrofits. To assess onboard concentrations, continuous PM2.5 data were collected during 85 trips aboard 43 school buses during normal driving routines, and aboard hybrid lead vehicles traveling in front of the monitored buses during 46 trips. Ordinary and partial least square regression models for PM2.5 onboard buses were created with and without control for roadway concentrations, which were also modeled. Predictors examined included ambient PM2.5 levels, ambient weather, and bus and route characteristics. Concentrations aboard school buses (21 μg/m3) were four and two-times higher than ambient and roadway levels, respectively. Differences in PM2.5 levels between the buses and lead vehicles indicated an average of 7 μg/m3 originating from the bus's own emission sources. While roadway concentrations were dominated by ambient PM2.5, bus concentrations were influenced by bus age, diesel oxidative catalysts, and roadway concentrations. Cross validation confirmed the roadway models but the bus models were less robust. These results confirm that children are exposed to air pollution from the bus and other roadway traffic while riding school buses. In-cabin air pollution is higher than roadway concentrations and is likely influenced by bus characteristics. PMID:18985175

Predicting airborne particle levels aboard Washington State school buses

NASA Astrophysics Data System (ADS)

Adar, Sara D.; Davey, Mark; Sullivan, James R.; Compher, Michael; Szpiro, Adam; Sally Liu, L.-J.

School buses contribute substantially to childhood air pollution exposures yet they are rarely quantified in epidemiology studies. This paper characterizes fine particulate matter (PM 2.5) aboard school buses as part of a larger study examining the respiratory health impacts of emission reducing retrofits. To assess onboard concentrations, continuous PM 2.5 data were collected during 85 trips aboard 43 school buses during normal driving routines, and aboard hybrid lead vehicles traveling in front of the monitored buses during 46 trips. Ordinary and partial least squares regression models for PM 2.5 onboard buses were created with and without control for roadway concentrations, which were also modeled. Predictors examined included ambient PM 2.5 levels, ambient weather, and bus and route characteristics. Average concentrations aboard school buses (21 μg m -3) were four and two-times higher than ambient and roadway levels, respectively. Differences in PM 2.5 levels between the buses and lead vehicles indicated an average of 7 μg m -3 originating from the bus's own emission sources. While roadway concentrations were dominated by ambient PM 2.5, bus concentrations were influenced by bus age, diesel oxidative catalysts, and roadway concentrations. Cross-validation confirmed the roadway models but the bus models were less robust. These results confirm that children are exposed to air pollution from the bus and other roadway traffic while riding school buses. In-cabin air pollution is higher than roadway concentrations and is likely influenced by bus characteristics.

Robust planning of dynamic wireless charging infrastructure for battery electric buses

DOE PAGES

Liu, Zhaocai; Song, Ziqi

2017-10-01

Battery electric buses with zero tailpipe emissions have great potential in improving environmental sustainability and livability of urban areas. However, the problems of high cost and limited range associated with on-board batteries have substantially limited the popularity of battery electric buses. The technology of dynamic wireless power transfer (DWPT), which provides bus operators with the ability to charge buses while in motion, may be able to effectively alleviate the drawbacks of electric buses. In this paper, we address the problem of simultaneously selecting the optimal location of the DWPT facilities and designing the optimal battery sizes of electric buses formore » a DWPT electric bus system. The problem is first constructed as a deterministic model in which the uncertainty of energy consumption and travel time of electric buses is neglected. The methodology of robust optimization (RO) is then adopted to address the uncertainty of energy consumption and travel time. The affinely adjustable robust counterpart (AARC) of the deterministic model is developed, and its equivalent tractable mathematical programming is derived. Both the deterministic model and the robust model are demonstrated with a real-world bus system. The results of our study demonstrate that the proposed deterministic model can effectively determine the allocation of DWPT facilities and the battery sizes of electric buses for a DWPT electric bus system; and the robust model can further provide optimal designs that are robust against the uncertainty of energy consumption and travel time for electric buses.« less

Quantification of Self Pollution from Two Diesel School Buses using Three Independent Methods.

PubMed

Liu, L-J Sally; Phuleria, Harish C; Webber, Whitney; Davey, Mark; Lawson, Douglas R; Ireson, Robert G; Zielinska, Barbara; Ondov, John M; Weaver, Christopher S; Lapin, Charles A; Easter, Michael; Hesterberg, Thomas W; Larson, Timothy

2010-09-01

We monitored two Seattle school buses to quantify the buses' self pollution using the dual tracers (DT), lead vehicle (LV), and chemical mass balance (CMB) methods. Each bus drove along a residential route simulating stops, with windows closed or open. Particulate matter (PM) and its constituents were monitored in the bus and from a LV. We collected source samples from the tailpipe and crankcase emissions using an on-board dilution tunnel. Concentrations of PM(1), ultrafine particle counts, elemental and organic carbon (EC/OC) were higher on the bus than the LV. The DT method estimated that the tailpipe and the crankcase emissions contributed 1.1 and 6.8 mug/m(3) of PM(2.5) inside the bus, respectively, with significantly higher crankcase self pollution (SP) when windows were closed. Approximately two-thirds of in-cabin PM(2.5) originated from background sources. Using the LV approach, SP estimates from the EC and the active personal DataRAM (pDR) measurements correlated well with the DT estimates for tailpipe and crankcase emissions, respectively, although both measurements need further calibration for accurate quantification. CMB results overestimated SP from the DT method but confirmed crankcase emissions as the major SP source. We confirmed buses' SP using three independent methods and quantified crankcase emissions as the dominant contributor.

Quantification of self pollution from two diesel school buses using three independent methods

NASA Astrophysics Data System (ADS)

Sally Liu, L.-J.; Phuleria, Harish C.; Webber, Whitney; Davey, Mark; Lawson, Douglas R.; Ireson, Robert G.; Zielinska, Barbara; Ondov, John M.; Weaver, Christopher S.; Lapin, Charles A.; Easter, Michael; Hesterberg, Thomas W.; Larson, Timothy

2010-09-01

We monitored two Seattle school buses to quantify the buses' self pollution using the dual tracers (DT), lead vehicle (LV), and chemical mass balance (CMB) methods. Each bus drove along a residential route simulating stops, with windows closed or open. Particulate matter (PM) and its constituents were monitored in the bus and from a LV. We collected source samples from the tailpipe and crankcase emissions using an on-board dilution tunnel. Concentrations of PM 1, ultrafine particle counts, elemental and organic carbon (EC/OC) were higher on the bus than the LV. The DT method estimated that the tailpipe and the crankcase emissions contributed 1.1 and 6.8 μg m -3 of PM 2.5 inside the bus, respectively, with significantly higher crankcase self pollution (SP) when windows were closed. Approximately two-thirds of in-cabin PM 2.5 originated from background sources. Using the LV approach, SP estimates from the EC and the active personal DataRAM (pDR) measurements correlated well with the DT estimates for tailpipe and crankcase emissions, respectively, although both measurements need further calibration for accurate quantification. CMB results overestimated SP from the DT method but confirmed crankcase emissions as the major SP source. We confirmed buses' SP using three independent methods and quantified crankcase emissions as the dominant contributor.

Analysis of real-time variables affecting children's exposure to diesel-related pollutants during school bus commutes in Los Angeles

NASA Astrophysics Data System (ADS)

Sabin, Lisa D.; Kozawa, Kathleen; Behrentz, Eduardo; Winer, Arthur M.; Fitz, Dennis R.; Pankratz, David V.; Colome, Steven D.; Fruin, Scott A.

Variables affecting children's exposure during school bus commutes were investigated using real-time measurements of black carbon (BC), particle-bound polycyclic aromatic hydrocarbons (PB-PAH) and nitrogen dioxide (NO 2) inside 3 conventional diesel school buses, a particle trap-outfitted (TO) diesel school bus and a compressed natural gas (CNG) school bus, while traveling along an urban Los Angeles Unified School District bus route. A video camera was mounted at the front of each bus to record roadway conditions ahead of the bus during each commute. The videotapes from 12 commutes, in conjunction with pollutant concentration time series, were used to determine the influence of variables such as vehicles being followed, bus type and roadway type on pollutant concentrations inside the bus. For all buses tested, the highest concentrations of BC, PB-PAH and NO 2 were observed when following a diesel school bus, especially if that bus was emitting visible exhaust. This result was important because other diesel school buses were responsible for the majority of the diesel vehicle encounters, primarily due to caravanning with each other when leaving a school at the same time. Compared with following a gasoline vehicle or no target, following a smoky diesel school bus yielded BC and PB-PAH concentrations inside the cabin 8 and 11 times higher, respectively, with windows open, and ˜1.8 times higher for both pollutants with windows closed. When other diesel vehicles were not present, pollutant concentrations were highest inside the conventional diesel buses and lowest inside the CNG bus, while the TO diesel bus exhibited intermediate concentrations. Differences in pollutant concentrations between buses were most pronounced with the bus windows closed, and were attributed to a combination of higher concentrations in the exhaust and higher exhaust gas intrusion rates for the conventional diesel buses. Conventional diesel school buses can have a double exposure impact on commuting children: first, exposures to the exhaust from other nearby diesel school buses and, second, exposure to the bus's own exhaust through "self-pollution".

Project Startup: Evaluating the Performance of Electric Buses

DOE Office of Scientific and Technical Information (OSTI.GOV)

2016-04-01

The National Renewable Energy Laboratory (NREL) is evaluating the in-service performance of fast-charge battery electric buses compared to compressed natural gas (CNG) buses operated by Foothill Transit in West Covina, California. Launched in 2015 in collaboration with the California Air Resources Board, this study aims to improve understanding of the overall use and effectiveness of fast-charge electric buses and associated charging infrastructure in transit operation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feibel, C.E.

This study uses multiple data collection and research methods including in depth interviews, 271 surveys of shared taxi and minibus operators, participant observation, secondary sources, and the literature on public transport from low, medium, and high-income countries. Extensive use is also made of a survey administered in Istanbul in 1976 to 1935 paratransit operators. Primary findings are that private buses are more efficient than public buses on a cost per passenger-km basis, and that private minibuses are as efficient as public buses. In terms of energy efficiency, minibuses are almost as efficient as public and private buses using actual-occupancy levels.more » Large shared taxis are twice as cost and energy efficient as cars, and small shared taxis 50% more efficient. In terms of investment cost per seat, large shared taxis have the lowest cost followed by smaller shared taxis, minibuses, and buses. Considering actual occupancy levels, minibuses are only slightly less effective in terms of congestion than buses, and large and small shared taxis are twice as effective as cars. It is also shown that minibuses and shared taxis have better service quality than buses because of higher frequencies and speeds, and because they provide a much higher probability of getting a seat than buses. Analysis of regulation and policy suggests that there are many unintended cost of public-transport regulations.« less

Alternative Fuels Data Center: Rio Rico Fire District Turns Grease Into

Science.gov Websites

Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a school bus Michigan Transports Students March 31, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Electric Trucks Natural Gas Street Sweepers Improve Air Quality in New York March 11, 2010 Propane Buses Save Money for

Alternative Fuels Data Center: Baton Rouge School District Adds Propane

Science.gov Websites

Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a school bus Michigan Transports Students Vehicles June 8, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Electric Trucks Alternative Fuels Oct. 16, 2010 Propane Buses Save Money for Virginia Schools Feb. 25, 2010 MedCorp Fuels

Alternative Fuels Data Center: Boston Public Schools Moves to Propane

Science.gov Websites

Efficiency March 8, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a school bus to Alternative Fuel Vehicles June 8, 2012 Natural Gas School Buses Help Kansas City Save Money Nov National Park Commits to Alternative Fuels Oct. 16, 2010 Propane Buses Save Money for Virginia Schools Feb

Alternative Fuels Data Center: Krug Energy Opens Natural Gas Fueling

Science.gov Websites

Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Charging Stations Spread Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In Electric Bus

Alternative Fuels Data Center: Texas Law Enforcement Vehicles Fill up With

Science.gov Websites

. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Buses Save Money for Virginia Schools Feb. 25, 2010 Michigan Fleet Reduces Gasoline and Diesel Use Feb

Alternative Fuels Data Center: New Hampshire Cleans up with Biodiesel Buses

Science.gov Websites

Public Transit Efficiency March 8, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo Help Kansas City Save Money Nov. 12, 2011 Electric Trucks Deliver at Kansas City Schools Sept. 17, 2011 Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In Electric Bus

Alternative Fuels Data Center: Frito-Lay Delivers With Electric Truck Fleet

Science.gov Websites

. Rental Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1 Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In

Buses involved in fatal accidents factbook 2007

DOT National Transportation Integrated Search

2010-03-01

This document presents aggregate statistics on buses involved in traffic accidents in 2007. The : statistics are derived from the Buses Involved in Fatal Accidents (BIFA) file, compiled by the : University of Michigan Transportation Research Institut...

Acoustic Investigations into the Later Acquisition of Syllabic "-es" Plurals

ERIC Educational Resources Information Center

Mealings, Kiri T.; Cox. Felicity; Demuth, Katherine

2013-01-01

Purpose: Children acquire /-ez/ syllabic plurals (e.g., buses) later than /-s, -z/ segmental plurals (e.g., cats,dogs). In this study, the authors explored whether increased syllable number or segmental factors best explains poorer performance with syllabic plurals. Method: An elicited imitation experiment was conducted with 14 two-year-olds…

[Energy Conservation and Emissions Reduction Benefits Analysis for Battery Electric Buses Based on Travel Services].

PubMed

Lin, Xiao-dan; Tian, Liang; Lü, Bin; Yang, Jian-xin

2015-09-01

Battery Electric Bus (BEB) has become one of prior options of urban buses for its "zero emission" during the driving stage. However, the environmental performance of electric buses is affected by multi-factors from the point of whole life cycle. In practice, carrying capacity of BEB and power generation structures can both implement evident effects on the energy consumption and pollutants emission of BEB. Therefore, take the above factors into consideration, in this article, Life Cycle Assessment is employed to evaluate the energy conservation and emissions reduction benefits of BEB. Results indicate that, travel service is more reasonable as the functional unit, rather than mileage, since the carrying capacity of BEB is 15% lower than the diesel buses. Moreover, compared with diesel buses, the energy conservation and emissions reduction benefits of battery electric buses are all different due to different regional power structures. Specifically, the energy benefits are 7. 84%, 11. 91%, 26. 90%, 11. 15%, 19. 55% and 20. 31% respectively in Huabei, Huadong, Huazhong, Dongbei, Xibei and Nanfang power structure. From the point of comprehensive emissions reduction benefits, there is no benefit in Huabei power structure, as it depends heavily on coal. But in other areas, the comprehensive emissions reduction benefits of BEB are separately 3. 46%, 26. 81%, 1. 17%, 13. 74% and 17. 48% in Huadong, Huazhong, Dongbei, Xibei and Nanfang. Therefore, it suggests that, enlargement of carrying capacity should be taken as the most prior technology innovation direction for BEB, and the grids power structure should be taken into consideration when the development of BEB is in planning.

NREL: News - Hybrid Buses Operate With Lower Emissions, Greater Fuel

Science.gov Websites

Evaluation Project to collect fueling, maintenance, performance and emission data from NYCT. While the hybrid buses have greater fuel economy than diesel buses, maintenance costs were significantly higher due in

Wheelchair and Occupant Restraint on School Buses

DOT National Transportation Integrated Search

1990-05-01

This report presents the findings of a literature survey, wheelchair hardware survey, wheelchair usage on school buses survey and assessment of current worldwide standards to address securement of wheelchairs on school buses and other modes of public...

Health effects caused by primary fine particulate matter (PM2.5) emitted from buses in the Helsinki metropolitan area, Finland.

PubMed

Tainio, Marko; Tuomisto, Jouni T; Hänninen, Otto; Aarnio, Päivi; Koistinen, Kimmo J; Jantunen, Matti J; Pekkanen, Juha

2005-02-01

Fine particle (PM(2.5)) emissions from traffic have been associated with premature mortality. The current work compares PM(2.5)-induced mortality in alternative public bus transportation strategies as being considered by the Helsinki Metropolitan Area Council, Finland. The current bus fleet and transportation volume is compared to four alternative hypothetical bus fleet strategies for the year 2020: (1) the current bus fleet for 2020 traffic volume, (2) modern diesel buses without particle traps, (3) diesel buses with particle traps, and (4) buses using natural gas engines. The average population PM(2.5) exposure level attributable to the bus emissions was determined for the 1996-1997 situation using PM(2.5) exposure measurements including elemental composition from the EXPOLIS-Helsinki study and similar element-based source apportionment of ambient PM(2.5) concentrations observed in the ULTRA study. Average population exposure to particles originating from the bus traffic in the year 2020 is assumed to be proportional to the bus emissions in each strategy. Associated mortality was calculated using dose-response relationships from two large cohort studies on PM(2.5) mortality from the United States. Estimated number of deaths per year (90% confidence intervals in parenthesis) associated with primary PM(2.5) emissions from buses in Helsinki Metropolitan Area in 2020 were 18 (0-55), 9 (0-27), 4 (0-14), and 3 (0-8) for the strategies 1-4, respectively. The relative differences in the associated mortalities for the alternative strategies are substantial, but the number of deaths in the lowest alternative, the gas buses, is only marginally lower than what would be achieved by diesel engines equipped with particle trap technology. The dose-response relationship and the emission factors were identified as the main sources of uncertainty in the model.

Application of an Ir tracer to determine soot exposure to students commuting to school on Baltimore public buses

NASA Astrophysics Data System (ADS)

Wu, Charles C.; Suarez, Ana E.; Lin, Zhibo; Kidwell, Christopher B.; Borgoul, Polina V.; Caffrey, Peter F.; Ondov, John M.; Sattler, Barbara

An important component of urban aerosol, diesel soot is a known respiratory irritant and contains mutagenic and carcinogenic organic compounds. To estimate student exposures to soot emitted from public diesel buses during commutes to city high schools, a portion of the Baltimore municipal fuel supply was tagged with an iridium tracer and exposure was monitored during commutes with personal aerosol monitors as a part of an Environmental Justice Project. A total of 68.2 g of Ir as iridium(III)-2,4-pentanedionate were used to induce a concentration of 48.5 μg Ir ℓ -1 of fuel. Twenty samples were collected over 10 days while four students commuted on regularly scheduled buses and a fifth student commuted by private car. Individual samples integrated from 1 to 4 round trips. Iridium analyses were performed instrumentally after neutron activation with a detection limit (DL) of about 500 fg. For students commuting by bus and following protocols, Ir tracer concentrations ranged from 53±38 to >1980±49 fg m -3. Concentrations up to 3530±220 fg m -3 were observed for student #5, who sampled only when boarding and disembarking. Exposure were greatest for students commuting through the heavily trafficked central business district. Corresponding estimates of exposures to soot emitted from municipal buses ranged from ⩽3 to 82 ng soot m -3 (⩽145 ng m -3 for student #5), i.e. well below the exposure level of 2-10 μg m -3 total C from all sources, including the more than 30,000 diesel trucks which pass through the city's major toll facilities each day. Ir was undetectable in samples collected by the student commuting by car when its windows were closed, but comparable to those of the other students when commutes were made with windows open. The Ir tracer DL corresponds to about 21 ng soot, about half of which is carbon. This is far below the 230 ng reported for analysis by a highly sensitive thermal-optical technique.

Technology of Articulated Transit Buses

DOT National Transportation Integrated Search

1982-03-01

Since the first major demonstration of articulated buses in the mid 1970s and the first purchase in late 1978, interest in articulated buses in U.S. transit service has remained strong. This interest has been stimulated by the desire of public transi...

Buses involved in fatal accidents codebook 2008.

DOT National Transportation Integrated Search

2011-03-01

This report provides documentation for UMTRIs file of Buses Involved in Fatal Accidents (BIFA), 2008, : including distributions of the code values for each variable in the file. The 2008 BIFA file is a census of all : buses involved in a fatal acc...

Buses involved in fatal accidents codebook 2007.

DOT National Transportation Integrated Search

2009-12-01

This report provides documentation for UMTRIs file of Buses Involved in Fatal Accidents (BIFA), 2007, : including distributions of the code values for each variable in the file. The 2007 BIFA file is a census of all : buses involved in a fatal acc...

Lung cancer risk in male workers occupationally exposed to diesel motor emissions in Germany.

PubMed

Brüske-Hohlfeld, I; Möhner, M; Ahrens, W; Pohlabeln, H; Heinrich, J; Kreuzer, M; Jöckel, K H; Wichmann, H E

1999-10-01

Although in several epidemiological studies exposure to diesel motor emissions (DME) shows an elevated lung cancer risk, it is still controversial whether DME is a human carcinogen. In a pooled analysis of two case-control studies on lung cancer in Germany a total of 3498 male cases with histologically or cytologically ascertained lung cancer and 3541 male population controls were included. Information about lifelong occupational and smoking history was obtained by questionnaire. Drivers of lorries, buses, taxies, diesel locomotives and forklift trucks, bulldozers, graders, excavators, and tractors, were considered as exposed to DME and their cumulative exposure was estimated. All odds ratios were adjusted for smoking and asbestos exposure. The evaluation of lung cancer risk for all jobs with DME-exposure combined showed an odds ratio of OR=1.43 (95%-CI: 1.23-1.67). Most pronounced was the increase in lung cancer risk in heavy equipment operators (OR=2. 31 95%-CI: 1.44-3.70). The risk of tractor drivers increased with length of employment and reached statistical significance for exposures longer than 30 years (OR=6.81, 95%-CI: 1.17-39.51). The group of professional drivers (e.g., trucks, buses, and taxies), showed an increased risk only in West Germany (OR=1.44, 95%-CI: 1. 18-1.76), but not in East Germany (OR=0.83, 95%-CI: 0.60-1.14). DME-exposure in other traffic related jobs (e.g., diesel engine locomotive drivers, switchmen, forklift operators) was associated with an odds ratio of OR=1.53 (95%-CI: 1.04-2.24). The study provides further evidence that occupational exposure to diesel motor emissions is associated with an increased lung cancer risk. Copyright 1999 Wiley-Liss, Inc.

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

NASA Astrophysics Data System (ADS)

Zhang, Qunfang; Zhu, Yifang

2010-01-01

Increasing evidence has demonstrated toxic effects of vehicular emitted ultrafine particles (UFPs, diameter < 100 nm), with the highest human exposure usually occurring on and near roadways. Children are particularly at risk due to immature respiratory systems and faster breathing rates. In this study, children's exposure to in-cabin air 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.

Transit bus life cycle cost and year 2007 emissions estimation.

DOT National Transportation Integrated Search

2007-06-01

The report presents a study of transit bus life cycle cost (LCC) analysis, and projected transit bus emissions and fuel economy for 2007 : model year buses. It covers four bus types: diesel buses using ultra low sulfur diesel (ULSD), diesel buses usi...

36 CFR 1192.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... which operates with automated (driverless) individual vehicles or multi-car trains. Service may be on a..., forty- and thirty-foot transit buses, articulated buses, double-deck buses, and electric powered trolley... when occupied. Commuter rail car means a rail passenger car obtained by a commuter authority (as...

36 CFR 1192.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... which operates with automated (driverless) individual vehicles or multi-car trains. Service may be on a..., forty- and thirty-foot transit buses, articulated buses, double-deck buses, and electric powered trolley... when occupied. Commuter rail car means a rail passenger car obtained by a commuter authority (as...

36 CFR 1192.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... which operates with automated (driverless) individual vehicles or multi-car trains. Service may be on a..., forty- and thirty-foot transit buses, articulated buses, double-deck buses, and electric powered trolley... when occupied. Commuter rail car means a rail passenger car obtained by a commuter authority (as...

36 CFR 1192.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... which operates with automated (driverless) individual vehicles or multi-car trains. Service may be on a..., forty- and thirty-foot transit buses, articulated buses, double-deck buses, and electric powered trolley... when occupied. Commuter rail car means a rail passenger car obtained by a commuter authority (as...

Exact and Metaheuristic Approaches for a Bi-Objective School Bus Scheduling Problem.

PubMed

Chen, Xiaopan; Kong, Yunfeng; Dang, Lanxue; Hou, Yane; Ye, Xinyue

2015-01-01

As a class of hard combinatorial optimization problems, the school bus routing problem has received considerable attention in the last decades. For a multi-school system, given the bus trips for each school, the school bus scheduling problem aims at optimizing bus schedules to serve all the trips within the school time windows. In this paper, we propose two approaches for solving the bi-objective school bus scheduling problem: an exact method of mixed integer programming (MIP) and a metaheuristic method which combines simulated annealing with local search. We develop MIP formulations for homogenous and heterogeneous fleet problems respectively and solve the models by MIP solver CPLEX. The bus type-based formulation for heterogeneous fleet problem reduces the model complexity in terms of the number of decision variables and constraints. The metaheuristic method is a two-stage framework for minimizing the number of buses to be used as well as the total travel distance of buses. We evaluate the proposed MIP and the metaheuristic method on two benchmark datasets, showing that on both instances, our metaheuristic method significantly outperforms the respective state-of-the-art methods.

Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses : Third Evaluation Report

DOT National Transportation Integrated Search

2008-07-04

This report describes operations at Alameda-Contra Costa Transit District (AC Transit) for three prototype fuel cell buses and six diesel buses operating from the same location. This is the third evaluation report for this site, and it describes new ...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

46 CFR 111.30-19 - Buses and wiring.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Buses and wiring. 111.30-19 Section 111.30-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-19 Buses and wiring. (a) General. Each bus must meet the requirements of...

49 CFR 393.90 - Buses, standee line or bar.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Buses, standee line or bar. 393.90 Section 393.90 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.90 Buses, standee line or bar. Except...

Pupil Transportation.

ERIC Educational Resources Information Center

Bete, Tim, Ed.

1998-01-01

Presents the opinions of four transportation experts on issues related to school buses. The experts respond to the following questions: will advertisements placed on buses be used to generate district revenue; will compressed natural gas or liquefied natural gas become standard fuel for school buses; and will school bus seat belts be mandatory and…

Fuel Cell Buses in U.S. Transit Fleets: Current Status 2010

DOT National Transportation Integrated Search

2010-11-11

This past year has been one of transition for the introduction of fuel cell transit buses. The existing generation of fuel cell buses from Van Hool and UTC Power has continued to operate in service at three transit agencies. At the same time, a new g...

Was Busing the Problem?

ERIC Educational Resources Information Center

Watras, Joseph

2006-01-01

On 15 April 2002, the Dayton Board of Education, the Ohio State Department of Education, and the NAACP reached an agreement ending busing for racial balance in the city schools. Participants agreed that the era for litigated desegregation was over because busing had failed to raise academic achievement of African American children and court…

A measure for objects clustering in principal component analysis biplot: A case study in inter-city buses maintenance cost data

NASA Astrophysics Data System (ADS)

Ginanjar, Irlandia; Pasaribu, Udjianna S.; Indratno, Sapto W.

2017-03-01

This article presents the application of the principal component analysis (PCA) biplot for the needs of data mining. This article aims to simplify and objectify the methods for objects clustering in PCA biplot. The novelty of this paper is to get a measure that can be used to objectify the objects clustering in PCA biplot. Orthonormal eigenvectors, which are the coefficients of a principal component model representing an association between principal components and initial variables. The existence of the association is a valid ground to objects clustering based on principal axes value, thus if m principal axes used in the PCA, then the objects can be classified into 2m clusters. The inter-city buses are clustered based on maintenance costs data by using two principal axes PCA biplot. The buses are clustered into four groups. The first group is the buses with high maintenance costs, especially for lube, and brake canvass. The second group is the buses with high maintenance costs, especially for tire, and filter. The third group is the buses with low maintenance costs, especially for lube, and brake canvass. The fourth group is buses with low maintenance costs, especially for tire, and filter.

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2010 CFR

2010-10-01

....2, S4.4 or S4.5 of this section. S4.2Except for school buses, a head restraint that conforms to... position. For school buses, a head restraint that conforms to either S4.2 (a) or (b) of this section must... one of the following occurs: (i) Failure of the seat or seat back; or, (ii) Application of a load of...

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2011 CFR

2011-10-01

....2, S4.4 or S4.5 of this section. S4.2Except for school buses, a head restraint that conforms to... position. For school buses, a head restraint that conforms to either S4.2 (a) or (b) of this section must... one of the following occurs: (i) Failure of the seat or seat back; or, (ii) Application of a load of...

Popular Participation and Representation in the Urban Environment: The School Desegregation Issue in Los Angeles.

ERIC Educational Resources Information Center

Weatherford, M. Stephen

Most scholarly literature on school desegregation treats opposition to busing as racist, reactionary, or as springing from deeper conditions of alienation or anomie. From this viewpoint, anti-busing demonstrations are episodic, unorganized and not founded on any thoroughgoing comprehension of the immediate policy issue. Busing is merely the…

Optimal speed limits for school buses on Virginia highways : a report to Virginia's Superintendent of Public Instruction.

DOT National Transportation Integrated Search

1990-01-01

On Virginia's rural interstate highways there is a three-tiered speed limit: 45 mph for school buses, 55 mph for trucks, and 65 mph for other vehicles. On the urban interstate highways, school buses are restricted to 45 mph, but other traffic has a 5...

49 CFR 392.63 - Towing or pushing loaded buses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Towing or pushing loaded buses. 392.63 Section 392... COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.63 Towing or pushing loaded buses. No disabled bus with... passengers aboard for the purpose of towing or pushing any disabled motor vehicle, except in such...

White Opposition to Busing in Los Angeles: Is Self Interest Rejuvenated?

ERIC Educational Resources Information Center

Allen, H. M., Jr.; Sears, David O.

The conventional explanation for adult white opposition to busing for school desegregation emphasizes a rational, objective self interested component. Whites are seen as opposing busing because its costs far exceed its benefits. However, little of the social psychological literature supports this view. Studies by and large support the findings…

Evaluation of in-use fuel economy and on-board emissions for hybrid and regular CyRide transit buses.

DOT National Transportation Integrated Search

2012-10-01

The objective of this project was to evaluate the in-use fuel economy and emission differences between hybrid-electric and : conventional transit buses for the Ames, Iowa transit authority, CyRide. These CyRide buses were deployed in the fall of : 20...

49 CFR 393.62 - Emergency exits for buses.

Code of Federal Regulations, 2011 CFR

2011-10-01

... (including a school bus used in interstate commerce for non-school bus operations) with a GVWR of more than 4... manufacture. (2) Each bus (including a school bus used in interstate commerce for non-school bus operations... NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.62 Emergency exits for buses. (a) Buses...

49 CFR 393.62 - Emergency exits for buses.

Code of Federal Regulations, 2013 CFR

2013-10-01

... (including a school bus used in interstate commerce for non-school bus operations) with a GVWR of more than 4... manufacture. (2) Each bus (including a school bus used in interstate commerce for non-school bus operations... NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.62 Emergency exits for buses. (a) Buses...

49 CFR 393.62 - Emergency exits for buses.

Code of Federal Regulations, 2014 CFR

2014-10-01

... (including a school bus used in interstate commerce for non-school bus operations) with a GVWR of more than 4... manufacture. (2) Each bus (including a school bus used in interstate commerce for non-school bus operations... NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.62 Emergency exits for buses. (a) Buses...

49 CFR 393.62 - Emergency exits for buses.

Code of Federal Regulations, 2012 CFR

2012-10-01

... (including a school bus used in interstate commerce for non-school bus operations) with a GVWR of more than 4... manufacture. (2) Each bus (including a school bus used in interstate commerce for non-school bus operations... NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.62 Emergency exits for buses. (a) Buses...

Busing, Desegregation and Student Self-Concept.

ERIC Educational Resources Information Center

Felice, Lawrence G.

This paper reports findings from the first two years of a 3-year study to evaluate the effects of court-ordered busing in Waco, Texas. The objective of this study is to determine minority student achievement gains or losses, attitudes toward busing and school desegregation, the degree of interracial cooperation and acceptance in Waco schools, and…

Bus Ride to Nowhere.

ERIC Educational Resources Information Center

McGroarty, Daniel

1996-01-01

Describes the situation created by busing in Milwaukee's public schools. The rise of support for school choice developed out of the failure of busing, which was Milwaukee's solution to school problems. Wisconsin now has a private-school voucher law. Busing has been less onerous since the city was divided into five zones from which parents of…

Indoor Air Pollution in Non Ac Passenger Bus

NASA Astrophysics Data System (ADS)

El Husna, Iksiroh; Unzilatirrizqi, Rizal D. Yan El; Karyanto, Yudi; Sunoko, Henna R.

2018-02-01

Passenger buses have been one of favorite means of transportation in Indonesia due to its affordability and flexibility. Intensity of human activities during the trip in the buses have a potential of causing indoor air pollution (polusi udara dalam ruang; PUDR). The indoor air pollution has an impact of 1000-time bigger than outdoor air pollution (polusi udara luar ruang; PULR) on lung. This study aimed to find out indoor air pollution rate of non air conditioned buses using an approach to biological agent pollutant source. The study applied an analysis restricted to microorganisms persistence as one of the sources of the indoor air pollution. The media were placed in different parts of the non AC buses. This study revealed that fungs were found in the non AC buses. They became contaminants and developed pathogenic bacteria that caused air pollution.

In-use fuel economy of hybrid-electric school buses in Iowa.

PubMed

Hallmark, Shauna; Sperry, Bob; Mudgal, Abhisek

2011-05-01

Although it is much safer and more fuel-efficient to transport children to school in buses than in private vehicles, school buses in the United States still consume 822 million gal of diesel fuel annually, and school transportation costs can account for a significant portion of resource-constrained school district budgets. Additionally, children in diesel-powered school buses may be exposed to higher levels of particulates and other pollutants than children in cars. One solution to emission and fuel concerns is use of hybrid-electric school buses, which have the potential to reduce emissions and overall lifecycle costs compared with conventional diesel buses. Hybrid-electric technologies are available in the passenger vehicle market as well as the transit bus market and have a track record indicating fuel economy and emissions benefits. This paper summarizes the results of an in-use fuel economy evaluation for two plug-in hybrid school buses deployed in two different school districts in Iowa. Each school district selected a control bus with a route similar to that of the hybrid bus. Odometer readings, fuel consumption, and maintenance needs were recorded for each bus. The buses were deployed in 2008 and data were collected through May 2010. Fuel consumption was calculated for each school district. In Nevada, IA, the overall average fuel economy was 8.23 mpg for the hybrid and 6.35 mpg for the control bus. In Sigourney, IA, the overall average fuel economy was 8.94 mpg for the hybrid and 6.42 mpg for the control bus. The fuel consumption data were compared for the hybrid and control buses using a Wilcoxon signed rank test. Results indicate that fuel economy for the Nevada hybrid bus was 29.6% better than for the Nevada control bus, and fuel economy for the Sigourney hybrid bus was 39.2% higher than for the Sigourney control bus. Both differences were statistically significant.

Using Credit Cards To Pay Bus Fares in Phoenix

DOT National Transportation Integrated Search

1996-01-01

In 1991 the City of Phoenix Public Transit System, first in the nation to install magnetic card readers on the electronic fareboxes in its buses, implemented a program known as Bus Card Plus, which billed employers for trips made by employees using e...

Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Fifth Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudy, Leslie; Post, Matthew; Jeffers, Matthew

This report presents results of a demonstration of fuel cell electric buses (FCEB) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration, which includes 13 advanced-design fuel cell buses and two hydrogen fueling stations. The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. NREL has published four previous reports describing operation of these buses. This report presents new and updated results covering data from January 2015 through December 2015.

Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results. Fourth Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudy, Leslie; Post, Matthew

This report presents results of a demonstration of fuel cell electric buses (FCEB) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration, which includes 12 advanced-design fuel cell buses and two hydrogen fueling stations. The FCEBs in service at AC Transit are 40-foot, low-floor buses built by Van Hool with a hybrid electric propulsion system that includes a US Hybrid fuel cell power system and EnerDel lithium-based energy storage system. The buses began revenue service in May 2010.

Zero Emission Bay Area (ZEBA) Fuel Cell Bus Demonstration Results: Sixth Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudy, Leslie; Post, Matthew B.; Jeffers, Matthew A.

This report presents results of a demonstration of fuel cell electric buses (FCEB) operating in Oakland, California. Alameda-Contra Costa Transit District (AC Transit) leads the Zero Emission Bay Area (ZEBA) demonstration, which includes 13 advanced-design fuel cell buses and two hydrogen fueling stations. The ZEBA partners are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. NREL has published five previous reports describing operation of these buses. This report presents new and updated results covering data from January 2016 through December 2016.

Big Brother Is Watching: Video Surveillance on Buses

ERIC Educational Resources Information Center

Sloggett, Joel

2009-01-01

Many school districts in North America have adopted policies to permit cameras on their properties and, when needed, on buses used to transport students. With regard to school buses, the camera is typically a tool for gathering information to monitor behavior or to help investigate a complaint about behavior. If a picture is worth a thousand…

Alternative Fuels Data Center: Biodiesel and Propane Fuel Buses for Dallas

Science.gov Websites

Leads in Alternative Fuel Use and Public Transit Efficiency March 8, 2014 Renzenberger Inc Saves Money Vehicles March 31, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In

Alternative Fuels Data Center: Deploying Clean Buses in Texas through

Science.gov Websites

money for large expenditures--new school buses are a perfect example and offer the perfect opportunity a potential penalty or fine when that money is put toward an SEP. Municipalities may offset 100% of the problem schools have with finding money for large expenditures-new school buses are a perfect

26 CFR 41.4483-2 - Exemption for certain transit-type buses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Exemption for certain transit-type buses. 41... Certain Highway Motor Vehicles § 41.4483-2 Exemption for certain transit-type buses. (a) In general. Use in any taxable period, or part thereof, of any bus of the transit type by any person who is engaged...

It's Not the Distance, "It's the Niggers." Comments on the Controversy Over School Busing.

ERIC Educational Resources Information Center

National Association for the Advancement of Colored People Legal Defense and Educational Fund, New York, NY.

This paper focuses on the political nature of the present busing controversy. It is felt that the proposed moratorium on busing threatens gains which have been made in previous years through institutional and judicial enforcement of the Civil Rights Act in providing equal educational opportunities to all children. The advantages and disadvantages…

The Bus Stops Here: The Case for Biodiesel in School Buses.

ERIC Educational Resources Information Center

Rao, Steven T.

2002-01-01

Suggests that diesel exhaust from most of the nation's school buses may be hazardous to children's health. Documents studies on the nature and potential magnitude of the risk to children and proposes replacing petroleum diesel with biodiesel as the fuel for school buses. Presents the merits and practicality of switching to biodiesel as a healthier…

49 CFR 393.62 - Emergency exits for buses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... NECESSARY FOR SAFE OPERATION Glazing and Window Construction § 393.62 Emergency exits for buses. (a) Buses... glazing if such glazing is not contained in a push-out window; or, at least 432 cm2 (67 square inches) of free opening resulting from opening of a push-out type window. No area shall be included in this...

School Buses Answer Calls for Help in Crises

ERIC Educational Resources Information Center

Borja, Rhea R.

2005-01-01

Five days after Hurricane Katrina struck New Orleans, a convoy of 142 air-conditioned school buses from the 209,000-student Texas district rumbled to life. Loaded with food and bottled water, staffed by 350 school employees, and accompanied by bus-repair trucks and a phalanx of school police cars, the yellow buses traveled all night to reach the…

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2014 CFR

2014-10-01

... seat back; or, (ii) Application of a load of 890N. S4.3[Reserved] S4.4.Except for school buses, a head... comply with, at the manufacturer's option, S4.2, S4.4 or S4.5 of this section. S4.2Except for school... outboard front designated seating position. For school buses, a head restraint that conforms to either S4.2...

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2013 CFR

2013-10-01

... seat back; or, (ii) Application of a load of 890N. S4.3[Reserved] S4.4.Except for school buses, a head... comply with, at the manufacturer's option, S4.2, S4.4 or S4.5 of this section. S4.2Except for school... outboard front designated seating position. For school buses, a head restraint that conforms to either S4.2...

49 CFR 571.202 - Standard No. 202; Head restraints; Applicable at the manufacturers option until September 1, 2009.

Code of Federal Regulations, 2012 CFR

2012-10-01

... seat back; or, (ii) Application of a load of 890N. S4.3[Reserved] S4.4.Except for school buses, a head... comply with, at the manufacturer's option, S4.2, S4.4 or S4.5 of this section. S4.2Except for school... outboard front designated seating position. For school buses, a head restraint that conforms to either S4.2...

Overhead electric power transmission line jumpering system for bundles of five or more subconductors

DOEpatents

Winkelman, Paul F.

1982-01-01

Jumpering of electric power transmission lines at a dead end tower. Two transmission line conductor bundles each contain five or more spaced apart subconductors (5) arranged in the shape of a cylinder having a circular cross section. The ends of each bundle of subconductors are attached with insulators to a dead end tower (1). Jumpering allows the electric current to flow between the two bundles of subconductors using jumper buses, internal jumper conductors, and external jumper conductors. One or more current collecting jumper buses (37) are located inside each bundle of subconductors with each jumper bus being attached to the end of a subconductor. Small-diameter internal jumper conductors (33) are located in the inherently electrically shielded area inside each bundle of subconductors with each subconductor (except ones having an attached jumper bus) having one internal jumper conductor connected between that subconductor's end and a jumper bus. Large-diameter external jumper conductors (9) are located outside each bundle of subconductors with one or more external jumper conductors being connected between the jumper buses in one bundle of subconductors and the jumper buses in the other bundle.

Too Many Choices?

ERIC Educational Resources Information Center

Gardner, Howard

2002-01-01

Reviews two books, "The Other Boston Busing Story: What's Won and Lost across the Boundary Line" (Susan E. Eaton) and "Kingdom of Children: Culture and Controversy in the Homeschooling Movement" (Mitchell L. Stevens), which provide revealing perspectives on the experiences of those American families who veture beyond the traditional local school.…

How Busing Burdened Blacks: Critical Race Theory and Busing for Desegregation in Nashville-Davidson County

ERIC Educational Resources Information Center

Woodward, Jennifer R.

2011-01-01

This article uses critical race theory, court opinions, newspapers, and interviews to explain how the burden of busing for desegregation was placed upon Blacks in Nashville, Tennessee and why the agenda of the litigants in the Kelley v. Metropolitan Board of Education cases shifted over time. The deliberate pace of the initial desegregation…

Alternative Fuels Data Center: Fleet Application for School Transportation

Science.gov Websites

/_kZz_IxCsQA Video thumbnail for Natural Gas School Buses Help Kansas City Save Money Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 https://www.youtube.com/embed/VYbBFQEKKCs Video thumbnail for , 2011 https://www.youtube.com/embed/ZJVXELFPywI Video thumbnail for Propane Buses Save Money for

49 CFR 37.71 - Purchase or lease of new non-rail vehicles by public entities operating fixed route systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... buses were to be lift-equipped and were to be otherwise accessible to and usable by individuals with disabilities; (2) Hydraulic, electromechanical, or other lifts for such new buses could not be provided by any qualified lift manufacturer to the manufacturer of such new buses in sufficient time to comply with the...

49 CFR 37.71 - Purchase or lease of new non-rail vehicles by public entities operating fixed route systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... buses were to be lift-equipped and were to be otherwise accessible to and usable by individuals with disabilities; (2) Hydraulic, electromechanical, or other lifts for such new buses could not be provided by any qualified lift manufacturer to the manufacturer of such new buses in sufficient time to comply with the...

Modification of Educational Equipment and Curriculum for Maximum Utilization by Physically Disabled Persons. The Transportation of Physically Disabled Students.

ERIC Educational Resources Information Center

Yuker, Harold E.; And Others

Guidelines for the transporting of physically handicapped children to school are given along with the types of vehicles, selection and training of drivers, problems of traveling time, and administration and financing of a transportation service. Vehicles described and compared include standard school buses, adapted buses, vans and compact buses,…

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

49 CFR 579.27 - Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Reporting requirements for manufacturers of fewer than 100 buses annually, for manufacturers of fewer than 500 emergency vehicles annually, for manufacturers of fewer than 5,000 light vehicles, medium-heavy vehicles (other than buses and emergency vehicles), motorcycles or trailers annually, for...

TITLE: Environmental, health, and safety issues offuel cells in transportation. Volume 1: Phosphoricacid fuel-cell buses

NASA Astrophysics Data System (ADS)

Ring, Shan

1994-12-01

The U.S. Department of Energy (DOE) chartered the Phosphoric Acid Fuel-Cell (PAFC) Bus Program to demonstrate the feasibility of fuel cells in heavy-duty transportation systems. As part of this program, PAFC- powered buses are being built to meet transit industry design and performance standards. Test-bed bus-1 (TBB-1) was designed in 1993 and integrated in March 1994. TBB-2 and TBB-3 are under construction and should be integrated in early 1995. In 1987 Phase 1 of the program began with the development and testing of two conceptual system designs- liquid- and air-cooled systems. The liquid-cooled PAFC system was chosen to continue, through a competitive award, into Phase H, beginning in 1991. Three hybrid buses, which combine fuel-cell and battery technologies, were designed during Phase 3. After completing Phase 2, DOE plans a comprehensive performance testing program (Phase H1) to verify that the buses meet stringent transit industry requirements. The Phase 3 study will evaluate the PAFC bus and compare it to a conventional diesel bus. This NREL study assesses the environmental, health, and safety (EH&S) issues that may affect the commercialization of the PAFC bus. Because safety is a critical factor for consumer acceptance of new transportation-based technologies the study focuses on these issues. The study examines health and safety together because they are integrally related. In addition, this report briefly discusses two environmental issues that are of concern to the Environmental Protection Agency (EPA). The first issue involves a surge battery used by the PAFC bus that contains hazardous constituents. The second issue concerns the regulated air emissions produced during operation of the PAFC bus.

Medium Truck Duty Cycle Data from Real-World Driving Environments: Project Interim Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Franzese, Oscar; Lascurain, Mary Beth; Capps, Gary J

2011-01-01

Since the early part of the 20th century, the US trucking industry has provided a safe and economical means of moving commodities across the country. At the present time, nearly 80% of the US domestic freight movement involves the use of trucks. The US Department of Energy (DOE) is spearheading a number of research efforts to improve heavy vehicle fuel efficiencies. This includes research in engine technologies (including hybrid and fuel cell technologies), lightweight materials, advanced fuels, and parasitic loss reductions. In addition, DOE is developing advanced tools and models to support heavy vehicle truck research, and is leading themore » 21st Century Truck Partnership whose stretch goals involve a reduction by 50% of the fuel consumption of heavy vehicles on a ton-mile basis. This Medium Truck Duty Cycle (MTDC) Project is a critical element in DOE s vision for improved heavy vehicle energy efficiency and is unique in that there is no other national database of characteristic duty cycles for medium trucks. It involves the collection of real-world data for various situational characteristics (rural/urban, freeway/arterial, congested/free-flowing, good/bad weather, etc.) and looks at the unique nature of medium trucks drive cycles (stop-and-go delivery, power takeoff, idle time, short-radius trips), to provide a rich source of data that can contribute to the development of new tools for fuel efficiency and modeling, provide DOE a sound basis upon which to make technology investment decisions, and provide a national archive of real-world-based medium-truck operational data to support heavy vehicle energy efficiency research. The MTDC project involves a two-part field operational test (FOT). For the Part-1 FOT, three vehicles, each from two vocations (urban transit and dry-box delivery) were instrumented for one year of data collection. The Part-2 FOT will involve the towing/recovery and utility vocations. The vehicles participating in the MTDC project are doing so through gratis partnerships in return for early access to the results of this study. Partnerships such as these are critical to FOTs in which real-world data is being collected. In Part 1 of the project, Oak Ridge National Laboratory(ORNL) established partnerships with the H.T. Hackney Company, one of the largest wholesale distributors in the country, distributing products to 21 states; and with the Knoxville Area Transit (KAT), the City of Knoxville s transit system, operating services across the city of Knoxville and parts of Knox co. These partnerships and agreements provided ORNL access to three Class-7 2005/2007 International day-cab tractors, model 8600, which regularly haul 28 ft pup trailers (H.T. Hackney Co) and three Class-7 2005 Optima LF-34 buses (KAT), for collection of duty cycle data. In addition, ORNL has collaborated with the Federal Motor Carrier Safety Administration (FMCSA) to determine if there were possible synergies between this duty cycle data collection effort and FMCSA s need to learn more about the operation and duty cycles of the second-largest fuel consuming commercial vehicle category in the US. FMCSA s primary interest was in collecting safety data relative to the driver, carrier, and vehicle. In order to collect the duty cycle and safety-related data, ORNL developed a data acquisition and wireless communication system that was placed on each test vehicle. Each signal recorded in this FOT was collected by means of one of the instruments incorporated into each data acquisition system (DAS). Native signals were obtained directly from the vehicle s J1939 and J1708 data buses. A VBOX II Lite collected Global Positioning System related information including speed, acceleration, and spatial location information at a rate of 5 Hz, and communicated this data via the CAN (J1939) protocol. The Air-Weigh LoadMaxx, a self-weighing system which determines the vehicle s gross weight by means of pressure transducers and posts the weight to the vehicle s J1939 data bus, was used to collect vehicle payload information. A cellular modem, the Raven X EVDO V4221, facilitated the communication between the eDAQ-lite (the data collection engine of the system) and the user, via the internet. The modem functioned as a wireless gateway, allowing data retrievals and system checks to be performed remotely. Also, and in partnership with FMCSA, two additional safety sensors were installed on the combination vehicles: the MGM e-Stroke brake monitoring system and the Tire SafeGuard tire pressure monitoring system. Both of these systems posted data to the J1939 data bus, enabling these signals to be read without any additional DAS interface hardware. Seventy-three signals from the different deployed sensors and available vehicle systems were collected. Because of the differences in vehicle data buses (i.e., J1939 and J1708 data buses), not all desired signals were available for both types of vehicles. The s...« less

School buses, diesel emissions, and respiratory health.

PubMed

Beatty, Timothy K M; Shimshack, Jay P

2011-09-01

School buses contribute disproportionately to ambient air quality, pollute near schools and residential areas, and their emissions collect within passenger cabins. This paper examines the impact of school bus emissions reductions programs on health outcomes. A key contribution relative to the broader literature is that we examine localized pollution reduction programs at a fine level of aggregation. We find that school bus retrofits induced reductions in bronchitis, asthma, and pneumonia incidence for at-risk populations. Back of the envelope calculations suggest conservative benefit-cost ratios between 7:1 and 16:1. Copyright © 2011 Elsevier B.V. All rights reserved.

Stress, Chemical Defense Agents and Cholinergic Receptors

DTIC Science & Technology

1989-11-30

reasons: I) Bused on the observations of Dam et al. (1982), i.e., low-dose oxotremorine activation of cerebral glucose utilization in cortical layers IVNb...QNB Lower: Localization of the binding of 2.0 nM ( H]- Oxotremorine -M The highest levels of binding for both radioligands are observed in the cerebral

Gaseous emissions from compressed natural gas buses in urban road and highway tests in China.

PubMed

Yue, Tingting; Chai, Fahe; Hu, Jingnan; Jia, Ming; Bao, Xiaofeng; Li, Zhenhua; He, Liqang; Zu, Lei

2016-10-01

The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas (CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0-10km/hr were increased to 10-20km/hr, the CO 2 , CO, nitrogen oxide (NO x ), and total hydrocarbon (THC) emission factors decreased by (71.6±4.3)%, (65.6±9.5)%, (64.9±9.2)% and (67.8±0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards (Euro IV) did not have lower emission factors than the Chongqing coaches with Euro II emission standards. Both the higher emission factors at 0-10km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO 2 and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most (by 83.2%), followed by the THC emission factors, which decreased by 67.1%. Copyright © 2016. Published by Elsevier B.V.

26 CFR 48.6421-2 - Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... gasoline used in intercity, local, or school buses. 48.6421-2 Section 48.6421-2 Internal Revenue INTERNAL... Manufacturers Taxes § 48.6421-2 Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses. (a) In general. If gasoline is used in an intercity or local bus while engaged in...

26 CFR 48.6421-2 - Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... gasoline used in intercity, local, or school buses. 48.6421-2 Section 48.6421-2 Internal Revenue INTERNAL... Manufacturers Taxes § 48.6421-2 Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses. (a) In general. If gasoline is used in an intercity or local bus while engaged in...

26 CFR 48.6421-2 - Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... gasoline used in intercity, local, or school buses. 48.6421-2 Section 48.6421-2 Internal Revenue INTERNAL... Manufacturers Taxes § 48.6421-2 Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses. (a) In general. If gasoline is used in an intercity or local bus while engaged in...

26 CFR 48.6421-2 - Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... gasoline used in intercity, local, or school buses. 48.6421-2 Section 48.6421-2 Internal Revenue INTERNAL... Manufacturers Taxes § 48.6421-2 Credits or payments to ultimate purchasers of gasoline used in intercity, local, or school buses. (a) In general. If gasoline is used in an intercity or local bus while engaged in...

Exact and Metaheuristic Approaches for a Bi-Objective School Bus Scheduling Problem

PubMed Central

Chen, Xiaopan; Kong, Yunfeng; Dang, Lanxue; Hou, Yane; Ye, Xinyue

2015-01-01

As a class of hard combinatorial optimization problems, the school bus routing problem has received considerable attention in the last decades. For a multi-school system, given the bus trips for each school, the school bus scheduling problem aims at optimizing bus schedules to serve all the trips within the school time windows. In this paper, we propose two approaches for solving the bi-objective school bus scheduling problem: an exact method of mixed integer programming (MIP) and a metaheuristic method which combines simulated annealing with local search. We develop MIP formulations for homogenous and heterogeneous fleet problems respectively and solve the models by MIP solver CPLEX. The bus type-based formulation for heterogeneous fleet problem reduces the model complexity in terms of the number of decision variables and constraints. The metaheuristic method is a two-stage framework for minimizing the number of buses to be used as well as the total travel distance of buses. We evaluate the proposed MIP and the metaheuristic method on two benchmark datasets, showing that on both instances, our metaheuristic method significantly outperforms the respective state-of-the-art methods. PMID:26176764

Bus 54 -- Where are you? A school bus intelligent information system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Truett, L.F.; Moore, S.; Tonn, B.

1998-07-01

Although major accidents involving school buses are rare (only about 0.3% of all fatal crashes since 1986 are classified as school-bus-related), even minor accidents and breakdowns cause a great deal of parental anxiety. The objective of this research is to design an efficient, cost-effective, accurate, and secure system that will track individual school buses and communicate appropriate information to the school system`s central administration unit, to the school transportation administrator, and to parents of children on the bus. The greatest benefit of the proposed information system is that parents and officials can always know the location and condition (these conditionsmore » would vary depending on the needs of a particular school system) of the school buses. In case of an accident or mechanical problem, when emergency crews are needed, they can be dispatched almost immediately with a good understanding of the problem and the exact location of the bus. In addition to being able to track the bus while the child is on board, parents will be able to determine the location of their child`s bus prior to its arrival in the morning in order to prevent the child from needing to wait outside in inclement weather. The information available to parents can also be expanded to include maps of limited routes (e.g., snow routes). Basically, the Bus 54 concept consists of a bus component and a central data processing unit. Each bus will be outfitted with a global positioning satellite (GPS) device, a wireless communication device, and wireless data communication service. The central data processing unit will receive and process information from the buses and provide information access to parents and officials via an Internet link.« less

Experimental and statistical analyses to characterize in-vehicle fine particulate matter behavior inside public transit buses operating on B20-grade biodiesel fuel

NASA Astrophysics Data System (ADS)

Vijayan, Abhilash; Kumar, Ashok

2010-11-01

This paper presents results from an in-vehicle air quality study of public transit buses in Toledo, Ohio, involving continuous monitoring, and experimental and statistical analyses to understand in-vehicle particulate matter (PM) behavior inside buses operating on B20-grade biodiesel fuel. The study also focused on evaluating the effects of vehicle's fuel type, operating periods, operation status, passenger counts, traffic conditions, and the seasonal and meteorological variation on particulates with aerodynamic diameter less than 1 micron (PM 1.0). The study found that the average PM 1.0 mass concentrations in B20-grade biodiesel-fueled bus compartments were approximately 15 μg m -3, while PM 2.5 and PM 10 concentration averages were approximately 19 μg m -3 and 37 μg m -3, respectively. It was also observed that average hourly concentration trends of PM 1.0 and PM 2.5 followed a "μ-shaped" pattern during transit hours. Experimental analyses revealed that the in-vehicle PM 1.0 mass concentrations were higher inside diesel-fueled buses (10.0-71.0 μg m -3 with a mean of 31.8 μg m -3) as compared to biodiesel buses (3.3-33.5 μg m -3 with a mean of 15.3 μg m -3) when the windows were kept open. Vehicle idling conditions and open door status were found to facilitate smaller particle concentrations inside the cabin, while closed door facilitated larger particle concentrations suggesting that smaller particles were originating outside the vehicle and larger particles were formed within the cabin, potentially from passenger activity. The study also found that PM 1.0 mass concentrations at the back of bus compartment (5.7-39.1 μg m -3 with a mean of 28.3 μg m -3) were higher than the concentrations in the front (5.7-25.9 μg m -3 with a mean of 21.9 μg m -3), and the mass concentrations inside the bus compartment were generally 30-70% lower than the just-outside concentrations. Further, bus route, window position, and time of day were found to affect the in-vehicle PM concentrations significantly. Overall, the in-vehicle PM 1.0 concentrations inside the buses operating on B20-grade biodiesel ranged from 0.7 μg m -3 to 243 μg m -3, with a median of 11.6 μg m -3. Statistical models developed to study the effects of vehicle operation and ambient conditions on in-vehicle PM concentrations suggested that while open door status was the most important influencing variable for finer particles and higher passenger activity resulted in higher coarse particles concentrations inside the vehicle compartments, ambient PM concentrations contributed to all PM fractions inside the bus irrespective of particle size.

Method for Assessing Risk of Road Accidents in Transportation of School Children

NASA Astrophysics Data System (ADS)

Pogotovkina, N. S.; Volodkin, P. P.; Demakhina, E. S.

2017-11-01

The rationale behind the problem being investigated is explained by the remaining high level of the accident rates with the participation of vehicles carrying groups of children, including school buses, in the Russian Federation over the period of several years. The article is aimed at the identification of new approaches to improve the safety of transportation of schoolchildren in accordance with the Concept of children transportation by buses and the plan for its implementation. The leading approach to solve the problem under consideration is the prediction of accidents in the schoolchildren transportation. The article presents the results of the accident rate analysis with the participation of school buses in the Russian Federation for five years. Besides, a system to monitor the transportation of schoolchildren is proposed; the system will allow analyzing and forecasting traffic accidents which involve buses carrying groups of children, including school buses. In addition, the article presents a methodology for assessing the risk of road accidents during the transportation of schoolchildren.

Characterizing Non-Resolved Debris Through Spectral and Photometric Ground-Based Telescopic Data: What Can Laboratory Ground-truth Data Do for You?

NASA Technical Reports Server (NTRS)

Lederer, Susan

2017-01-01

NASA's ODPO has recently collected data of unresolved objects at GEO with the 3.8m UKIRT infrared telescope on Mauna Kea and the 1.3m MCAT visible telescope on Ascension Island. Analyses of SWIR data of rocket bodies and HS-376 solar-panel covered buses demonstrate the uniqueness of spectral signatures. Data of 3 classes of rocket bodies show similarities amongst a given class, but distinct differences from one class to another, suggesting that infrared reflectance spectra could effectively be used toward characterizing and constraining potential parent bodies of uncorrelated targets (UCTs). The Optical Measurements Center (OMC) at NASA JSC is designed to collect photometric signatures in the laboratory that can be used for comparison with telescopic data. NASA also has a spectral database of spacecraft materials for use with spectral unmixing models. Spectral unmixing of the HS-376 bus data demonstrates how absorption features and slopes can be used to constrain material characteristics of debris. Broadband photometry likewise can be compared with MCAT data of non-resolved debris images. Similar studies have been applied to IDCSP satellites to demonstrate how color-color photometry can be compared with lab data to constrain bulk materials signatures of spacecraft and debris.

Battery capacity and recharging needs for electric buses in city transit service

DOE PAGES

Gao, Zhiming; Lin, Zhenhong; LaClair, Tim J.; ...

2017-01-27

Our paper evaluates the energy consumption and battery performance of city transit electric buses operating on real day-to-day routes and standardized bus drive cycles, based on a developed framework tool that links bus electrification feasibility with real-world vehicle performance, city transit bus service reliability, battery sizing and charging infrastructure. The impacts of battery capacity combined with regular and ultrafast charging over different routes have been analyzed in terms of the ability to maintain city transit bus service reliability like conventional buses. These results show that ultrafast charging via frequent short-time boost charging events, for example at a designated bus stopmore » after completing each circuit of an assigned route, can play a significant role in reducing the battery size and can eliminate the need for longer duration charging events that would cause schedule delays. Furthermore, the analysis presented shows that significant benefits can be realized by employing multiple battery configurations and flexible battery swapping practices in electric buses. These flexible design and use options will allow electric buses to service routes of varying city driving patterns and can therefore enable meaningful reductions to the cost of the vehicle and battery while ensuring service that is as reliable as conventional buses.« less

Simultaneous determination of carbonyls and NO2 in exhausts of heavy-duty diesel trucks and transit buses by HPLC following 2,4-dinitrophenylhydrazine cartridge collection.

PubMed

Tang, Shida; Graham, Lisa; Shen, Ling; Zhou, Xianliang; Lanni, Thomas

2004-11-15

A method combining 2,4-dinitrophenylhydrazine (DNPH) cartridge sampling and high-performance liquid chromatography (HPLC) analysis has been used for the measurement of carbonyl and NO2 emissions from heavy-duty diesel trucks and transit buses. The reaction of NO2 with DNPH allows for the simultaneous and unambiguous determination of NO2 and carbonyl concentrations in exhaust samples. The potential coelution of the NO2-DNPH derivative with the formaldehyde-DNPH derivative under certain chromatographic conditions was investigated. Successful separation of these two species was achieved allowing for simultaneous determination of carbonyls and NO2 in the exhaust samples collected from heavy-duty diesel (HDD) trucks and diesel, diesel/electric hybrid, diesel equipped with the continuously regenerating technology (CRT) particle traps, and compressed natural gas (CNG) transit buses tested over various drive cycles. Elevated NO2 emissions from CRT-equipped buses were observed. The NO2/NOx volume ratios for HDD trucks and transit buses are discussed. A comparison of the DNPH derivatization with HPLC/UV-visible detection method with a chemiluminescence analyzer method for NO2 measurement is presented for a limited number of diesel/CRT and CNG buses.

Battery capacity and recharging needs for electric buses in city transit service

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Zhiming; Lin, Zhenhong; LaClair, Tim J.

Our paper evaluates the energy consumption and battery performance of city transit electric buses operating on real day-to-day routes and standardized bus drive cycles, based on a developed framework tool that links bus electrification feasibility with real-world vehicle performance, city transit bus service reliability, battery sizing and charging infrastructure. The impacts of battery capacity combined with regular and ultrafast charging over different routes have been analyzed in terms of the ability to maintain city transit bus service reliability like conventional buses. These results show that ultrafast charging via frequent short-time boost charging events, for example at a designated bus stopmore » after completing each circuit of an assigned route, can play a significant role in reducing the battery size and can eliminate the need for longer duration charging events that would cause schedule delays. Furthermore, the analysis presented shows that significant benefits can be realized by employing multiple battery configurations and flexible battery swapping practices in electric buses. These flexible design and use options will allow electric buses to service routes of varying city driving patterns and can therefore enable meaningful reductions to the cost of the vehicle and battery while ensuring service that is as reliable as conventional buses.« less

Gender differences in motion sickness history and susceptibility to optokinetic rotation-induced motion sickness.

PubMed

Park, A H; Hu, S

1999-11-01

The present study investigated gender differences in motion sickness history and susceptibility to optokinetic rotation-induced motion sickness. The study included two phases. In Phase 1, 485 subjects filled out a survey of previous incidence of motion sickness. Results indicated that women reported significantly greater incidence of feeling motion sickness than did men on buses, on trains, on planes, in cars, and on amusement rides before the age of 12 yr; and on buses, on trains, on planes, in boats, on ships, in cars, on amusement rides, and on swings between the ages of 12 and 25 yr. Women also reported significantly higher incidence of being actually sick than did men on buses before the age of 12 yr and on buses, on ships, and in cars between the ages of 12 and 25 yr. In Phase 2, each of the 47 subjects viewed an optokinetic rotating-drum for 16 min. Subjects' subjective symptoms of motion sickness (SSMS) were obtained during drum rotation. The results showed that there were no significant differences on SSMS scores between men and women. Although women reported greater incidence in motion sickness history, women did not differ from men in severity of symptoms of motion sickness while viewing a rotating optokinetic drum.

Study on the air pollution in typical transportation microenvironment: Characteristics and health risks.

PubMed

Weng, Mili; Jin, Xin

2015-01-01

The concentration of formaldehyde in micro-traffic atmospheric environment (including buses, cars, bus stations, and traffic artery) of Lin'an City was carefully investigated. The results showed that the formaldehyde average concentration was 0.0162 mg/m³ in the buses, 0.0225 mg/m³ in the cars, 0.0047 mg/m³ in the West Bus Stations, and 0.0133 mg/m³ in the East Bus Stations. The concentration of formaldehyde along the traffic artery decreased with the height increased. From 0 to 140 cm, the formaldehyde concentration decreased from 0.031 to 0.018 mg/m³. The formaldehyde concentration decreased when far away from the traffic artery. When the distance reached 200 m, the formaldehyde concentration decreased from 0.018 to 0.005 mg/m³. Based on the health risk assessment model, using 1 hr as the average retention time, the average health risk in buses, cars, and West/East Bus Stations was 2.106 × 10⁻⁴, 2.925 × 10⁻⁴, and 1.157 × 10⁻⁴, respectively.

Implementation Practices of Bilingual Education Programs.

ERIC Educational Resources Information Center

Ortiz, Flora Ida

The ethnographic study investigated the implementation practices of a bilingual education program. A school site containing factors which were determined to be prevalent across Title VII programs was selected from over 300 Title VII sites. In addition, the school also contained a local student population, i.e., no one was bused from elsewhere; two…

Exposure assessment of diesel bus emissions.

PubMed

Yip, Maricela; Madl, Pierre; Wiegand, Aaron; Hofmann, Werner

2006-12-01

The goal of this study was to measure ultrafine particle concentrations with diameters less than 1 mum emitted by diesel buses and to assess resulting human exposure levels. The study was conducted at the Woolloongabba Busway station in Brisbane, Australia in the winter months of 2002 during which temperature inversions frequently occurred. Most buses that utilize the station are fuelled by diesel, the exhaust of which contains a significant quantity of particle matter. Passengers waiting at the station are exposed to these particles emitted from the buses. During the course of this study, passenger census was conducted, based on video surveillance, yielding person-by-person waiting time data. Furthermore, a bus census revealed accurate information about the total number of diesel versus Compressed Natural Gas (CNG) powered buses. Background (outside of the bus station) and platform measurements of ultrafine particulate number size distributions were made to determine ambient aerosol concentrations. Particle number exposure concentration ranges from 10 and 40 to 60% of bus related exhaust fumes. This changes dramatically when considering the particle mass exposure concentration, where most passengers are exposed to about 50 to 80% of exhaust fumes. The obtained data can be very significant for comparison with similar work of this type because it is shown in previous studies that exhaust emissions causes cancer in laboratory animals. It was assumed that significant differences between platform and background distributions were due to bus emissions which, combined with passenger waiting times, yielded an estimate of passenger exposure to ultrafine particles from diesel buses. From an exposure point of view, the Busway station analyzed resembles a street canyon. Although the detected exhaust particle concentration at the outbound platform is found to be in the picogram range, exposure increases with the time passengers spend on the platform along with their breathing frequency.

Environmental, health, and safety issues of fuel cells in transportation. Volume 1: Phosphoric acid fuel-cell buses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ring, S

1994-12-01

The U.S. Department of Energy (DOE) chartered the Phosphoric Acid Fuel-Cell (PAFC) Bus Program to demonstrate the feasibility of fuel cells in heavy-duty transportation systems. As part of this program, PAFC- powered buses are being built to meet transit industry design and performance standards. Test-bed bus-1 (TBB-1) was designed in 1993 and integrated in March 1994. TBB-2 and TBB-3 are under construction and should be integrated in early 1995. In 1987 Phase I of the program began with the development and testing of two conceptual system designs- liquid- and air-cooled systems. The liquid-cooled PAFC system was chosen to continue, throughmore » a competitive award, into Phase H, beginning in 1991. Three hybrid buses, which combine fuel-cell and battery technologies, were designed during Phase III. After completing Phase II, DOE plans a comprehensive performance testing program (Phase HI) to verify that the buses meet stringent transit industry requirements. The Phase III study will evaluate the PAFC bus and compare it to a conventional diesel bus. This NREL study assesses the environmental, health, and safety (EH&S) issues that may affect the commercialization of the PAFC bus. Because safety is a critical factor for consumer acceptance of new transportation-based technologies the study focuses on these issues. The study examines health and safety together because they are integrally related. In addition, this report briefly discusses two environmental issues that are of concern to the Environmental Protection Agency (EPA). The first issue involves a surge battery used by the PAFC bus that contains hazardous constituents. The second issue concerns the regulated air emissions produced during operation of the PAFC bus.« less

Adopting Clean Fuels and Technologies on School Buses. Pollution and Health Impacts in Children.

PubMed

Adar, Sara D; D'Souza, Jennifer; Sheppard, Lianne; Kaufman, Joel D; Hallstrand, Teal S; Davey, Mark E; Sullivan, James R; Jahnke, Jordan; Koenig, Jane; Larson, Timothy V; Liu, L J Sally

2015-06-15

More than 25 million American children breathe polluted air on diesel school buses. Emission reduction policies exist, but the health impacts to individual children have not been evaluated. Using a natural experiment, we characterized the exposures and health of 275 school bus riders before, during, and after the adoption of clean technologies and fuels between 2005 and 2009. Air pollution was measured during 597 trips on 188 school buses. Repeated measures of exhaled nitric oxide (FeNO), lung function (FEV1, FVC), and absenteeism were also collected monthly (1,768 visits). Mixed-effects models longitudinally related the adoption of diesel oxidation catalysts (DOCs), closed crankcase ventilation systems (CCVs), ultralow-sulfur diesel (ULSD), or biodiesel with exposures and health. Fine and ultrafine particle concentrations were 10-50% lower on buses using ULSD, DOCs, and/or CCVs. ULSD adoption was also associated with reduced FeNO (-16% [95% confidence interval (CI), -21 to -10%]), greater changes in FVC and FEV1 (0.02 [95% CI, 0.003 to 0.05] and 0.01 [95% CI, -0.006 to 0.03] L/yr, respectively), and lower absenteeism (-8% [95% CI, -16.0 to -0.7%]), with stronger associations among patients with asthma. DOCs, and to a lesser extent CCVs, also were associated with improved FeNO, FVC growth, and absenteeism, but these findings were primarily restricted to patients with persistent asthma and were often sensitive to control for ULSD. No health benefits were noted for biodiesel. Extrapolating to the U.S. population, changed fuel/technologies likely reduced absenteeism by more than 14 million/yr. National and local diesel policies appear to have reduced children's exposures and improved health.

Adopting Clean Fuels and Technologies on School Buses. Pollution and Health Impacts in Children

PubMed Central

D’Souza, Jennifer; Sheppard, Lianne; Kaufman, Joel D.; Hallstrand, Teal S.; Davey, Mark E.; Sullivan, James R.; Jahnke, Jordan; Koenig, Jane; Larson, Timothy V.; Liu, L. J. Sally

2015-01-01

Rationale: More than 25 million American children breathe polluted air on diesel school buses. Emission reduction policies exist, but the health impacts to individual children have not been evaluated. Methods: Using a natural experiment, we characterized the exposures and health of 275 school bus riders before, during, and after the adoption of clean technologies and fuels between 2005 and 2009. Air pollution was measured during 597 trips on 188 school buses. Repeated measures of exhaled nitric oxide (FeNO), lung function (FEV1, FVC), and absenteeism were also collected monthly (1,768 visits). Mixed-effects models longitudinally related the adoption of diesel oxidation catalysts (DOCs), closed crankcase ventilation systems (CCVs), ultralow-sulfur diesel (ULSD), or biodiesel with exposures and health. Measurements and Main Results: Fine and ultrafine particle concentrations were 10–50% lower on buses using ULSD, DOCs, and/or CCVs. ULSD adoption was also associated with reduced FeNO (−16% [95% confidence interval (CI), −21 to −10%]), greater changes in FVC and FEV1 (0.02 [95% CI, 0.003 to 0.05] and 0.01 [95% CI, −0.006 to 0.03] L/yr, respectively), and lower absenteeism (−8% [95% CI, −16.0 to −0.7%]), with stronger associations among patients with asthma. DOCs, and to a lesser extent CCVs, also were associated with improved FeNO, FVC growth, and absenteeism, but these findings were primarily restricted to patients with persistent asthma and were often sensitive to control for ULSD. No health benefits were noted for biodiesel. Extrapolating to the U.S. population, changed fuel/technologies likely reduced absenteeism by more than 14 million/yr. Conclusions: National and local diesel policies appear to have reduced children’s exposures and improved health. PMID:25867003

Online Assessment of Voltage Stability in Power Systems with PMUs

NASA Astrophysics Data System (ADS)

Chitare, Prasad Bhagwat; Murthy Balijepalli, V. S. K.; Khaparde, S. A.

2013-05-01

Abstract: For the assessment of voltage instability which comprises the detection of voltage instability and identification of critical buses, two indices namely, system wide Qtax, and bus-specific qtax, are proposed. The Qtax, based on the sensitivity of the reactive power injections to the loading in the system provides early detection of impending voltage instability. The computed qtax indices identify the critcal buses among the load buses in the system. The identified critical buses provided optimal lacations for the corrective control actions for averting voltage instability. Additionally, for voltage stability monitoring, determining the poing of exhaustion of the reactive reserves in system is also crucial. This is addressed by proposed Q-Monitoring Index (QMI), which is the ratio of the reactive component of the source current to the sink current that flows through the adjacent transmission line. These proposed indices together can provide early indication to impending voltage instability. This has been illustrated on IEEE-39 bus system. The reactive support on identified critical buses results in maximum increase in the loadability of the system.

A case study of real-world tailpipe emissions for school buses using a 20% biodiesel blend.

PubMed

Mazzoleni, Claudio; Kuhns, Hampden D; Moosmüller, Hans; Witt, Jay; Nussbaum, Nicholas J; Oliver Chang, M-C; Parthasarathy, Gayathri; Nathagoundenpalayam, Suresh Kumar K; Nikolich, George; Watson, John G

2007-10-15

Numerous laboratory studies report carbon monoxide, hydrocarbon, and particulate matter emission reductions with a slight nitrogen oxides emission increase from engines operating with biodiesel and biodiesel blends as compared to using petroleum diesel. We conducted a field study on a fleet of school buses to evaluate the effects of biodiesel use on gaseous and particulate matter fuel-based emission factors under real-world conditions. The field experiment was carried out in two phases during winter 2004. In January (phase I), emissions from approximately 200 school buses operating on petroleum diesel were measured. Immediately after the end of the first phase measurement period, the buses were switched to a 20% biodiesel blend. Emission factors were measured again in March 2004 (phase II) and compared with the January emission factors. To measure gaseous emission factors we used a commercial gaseous remote sensor. Particulate matter emission factors were determined with a combination of the gaseous remote sensor, a Lidar (light detection and ranging), and transmissometer system developed at the Desert Research Institute of Reno, NV, U.S.A. Particulate matter emissions from school buses significantly increased (up to a factor of 1.8) after the switch from petroleum diesel to a 20% biodiesel blend. The fuel used during this campaign was provided by a local distributor and was independently analyzed at the end of the on-road experiment. The analysis found high concentrations of free glycerin and reduced flash points in the B 100 parent fuel. Both measures indicate improper separation and processing of the biodiesel product during production. The biodiesel fuels used in the school buses were not in compliance with the U.S.A. ASTM D6751 biodiesel standard that was finalized in December of 2001. The U.S.A. National Biodiesel Board has formed a voluntary National Biodiesel Accreditation Program for producers and marketers of biodiesel to ensure product quality and compliance with the ASTM standard. The results of our study underline the importance of the program since potential emission benefits from biodiesel may be reduced or even reversed without appropriate fuel quality control on real-world fuels.

DARPA Emerging Technologies

DTIC Science & Technology

2016-01-01

development requires wind tunnels and ranges that do not currently exist. Furthermore, continued technology matura- tion is needed for thermal management...designed with conceptual design engine model (at existing technology level), or existing propul- sion system, or modified propulsion system (e.g...internal cameras reading gauges and dials and switch positions , directly tapping into current or future avion- ics service buses and integrating

Driving When You Have Cataracts

MedlinePlus

... cabs; N shuttle buses or vans; and N public buses, trains and subways. I Also, senior centers, religious and other local service groups often offer transportation services for older adults in your community. Who ...

Will Your School Buses Rescue Us from the Energy Crisis?

ERIC Educational Resources Information Center

Shannon, Thomas A.

1980-01-01

This article introduces a series that discusses energy-saving programs for school transportation systems and the role of school buses in local emergency transportation and local public transportation. (IRT)

Optimum bus headway for preemption : a simulation approach

DOT National Transportation Integrated Search

1997-01-01

Preemption techniques are designed to provide preferential treatment for buses at signalized intersections. A preemption strategy, if properly designed, can provide continuous green phases for buses at successive intersections, thereby reducing trave...

76 FR 46892 - Agency Information Collection Activity Under OMB Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-03

... development and deployment of clean fuel and advanced propulsion technologies for transit buses. To meet... propulsion technologies for transit buses by providing funds for clean fuel vehicles and facilities. To meet...

Should Seat Belts Be Required on All School Buses?

ERIC Educational Resources Information Center

Mawdsley, Ralph D.

1996-01-01

Examines the limited case law involving seat belts for school buses and explores emerging legal issues surrounding use of common law causes of action to challenge school bus safety. (51 footnotes) (MLF)

Cost Effectiveness Analysis of Quasi-In-Motion Wireless Power Transfer for Plug-In Hybrid Electric Transit Buses from Fleet Perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Lijuan; Gonder, Jeff; Brooker, Aaron

This study evaluated the costs and benefits associated with the use of stationary-wireless-power-transfer-enabled plug-in hybrid electric buses and determined the cost effectiveness relative to conventional buses and hybrid electric buses. A factorial design was performed over a number of different battery sizes, charging power levels, and f bus stop charging stations. The net present costs were calculated for each vehicle design and provided the basis for design evaluation. In all cases, given the assumed economic conditions, the conventional bus achieved the lowest net present cost while the optimal plug-in hybrid electric bus scenario beat out the hybrid electric comparison scenario.more » The parameter sensitivity was also investigated under favorable and unfavorable market penetration assumptions.« less

Methicillin-resistant Staphylococcus aureus in public transportation vehicles (buses): another piece to the epidemiologic puzzle.

PubMed

Lutz, Jonathan K; van Balen, Joany; Crawford, John Mac; Wilkins, John R; Lee, Jiyoung; Nava-Hoet, Rocio C; Hoet, Armando E

2014-12-01

Little is known about the occurrence and epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in public transportation in the United States. This research sought to determine the background prevalence and phenotypic and genotypic characteristics of MRSA strains circulating on buses from a large, metropolitan transportation agency. Electrostatic wipes were used to collect 237 surface samples from 40 buses randomly selected from July-October 2010. Six samples were collected from each bus immediately postservice and before any cleaning and disinfection. Positive isolates were analyzed for antibiotic resistance, staphylococcal cassette chromosome mec (SCCmec) type, and pulsed-field gel electrophoresis; and potential epidemiologic factors were examined. Of the buses, 68% (27/40) were contaminated with S aureus, and 63% (25/40) were contaminated with MRSA. Seats and seat rails were the surfaces most frequently contaminated, followed by the back door and stanchions. Most (62.9%) of the MRSA isolates were classified as community-associated MRSA clones (SCCmec type IV), and 22.9% were health care-associated MRSA clones (SCCmec type II). Of the MRSA strains, 65% (5/20) were multidrug resistant. MRSA was frequently isolated from commonly touched surfaces in buses serving both hospital and community routes. Phenotypic and genotypic analysis demonstrated that buses may be effective mixing vessels for MRSA strains of both community and health care-associated origin. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

The Design of a Fault-Tolerant COTS-Based Bus Architecture

NASA Technical Reports Server (NTRS)

Chau, Savio N.; Alkalai, Leon; Burt, John B.; Tai, Ann T.

1999-01-01

In this paper, we report our experiences and findings on the design of a fault-tolerant bus architecture comprised of two COTS buses, the IEEE 1394 and the 12C. This fault-tolerant bus is the backbone system bus for the avionics architecture of the X2000 program at the Jet Propulsion Laboratory. COTS buses are attractive because of the availability of low cost commercial products. However, they are not specifically designed for highly reliable applications such as long-life deep-space missions. The X2000 design team has devised a multi-level fault tolerance approach to compensate for this shortcoming of COTS buses. First, the approach enhances the fault tolerance capabilities of the IEEE 1394 and 12 C buses by adding a layer of fault handling hardware and software. Second, algorithms are developed to enable the IEEE 1394 and the 12 C buses assist each other to isolate and recovery from faults. Third, the set of IEEE 1394 and 12 C buses is duplicated to further enhance system reliability. The X2000 design team has paid special attention to guarantee that all fault tolerance provisions will not cause the bus design to deviate from the commercial standard specifications. Otherwise, the economic attractiveness of using COTS will be diminished. The hardware and software design of the X2000 fault-tolerant bus are being implemented and flight hardware will be delivered to the ST4 and Europa Orbiter missions.

Emission Standards, Public Transit, and Infant Health.

PubMed

Ngo, Nicole S

Transit buses are an integral part of urban life. They reduce externalities generated from private vehicles and increase geographic mobility. However, unlike most private vehicles in the United States, they use diesel fuel and emit higher amounts of toxic pollutants. The U.S. Environmental Protection Agency set emission standards for transit buses starting in 1988 that have been continually updated, but their public health and economic impacts are unclear due to scarce emissions data. I construct a novel panel dataset for the New York City (NYC) Transit bus fleet between 1990 and 2009 and examine the impact of bus pollution on infant health by using bus vintage as a proxy for emissions. I exploit the variation in vintage as older buses are retired and replaced with newer, lower-emitting buses forced to adhere to stricter emission standards. I then assign maternal exposure to bus vintage at the census block level. Findings suggest that maternal exposure to the oldest, unregulated buses is associated with modest reductions in birth weight and gestational age relative to newer buses that abide by emissions policies. I then conduct a back-of-the-envelope cost-benefit calculation and find net economic benefits of $53.3 million resulting from improved emission standards for the 2009 birth cohort in NYC. Since the treatment in this study clearly maps to federal emissions policies, these results are the first to provide credible evidence that transit bus emission standards had a positive effect on infant health.

Public transport as a reservoir of methicillin-resistant staphylococci.

PubMed

Stepanović, S; Cirković, I; Djukić, S; Vuković, D; Svabić-Vlahović, M

2008-10-01

The aim of this study was to explore the occurrence of methicillin-resistant staphylococci in a large urban public transport system. Samples were taken from hand rails, which passengers hold onto when they are standing. In total, 1400 swabs taken from 55 vehicles (trolleybuses, trams and buses) were examined. As many as 30.1% samples were positive for the presence of methicillin-resistant coagulase-negative staphylococci (MRCoNS), but none for methicillin-resistant Staphylococcus aureus (MRSA). MRCoNS were isolated from all 55 vehicles. Nearly 50% of MRCoNS isolates displayed resistance not only to beta-lactams, but at least to two or more other classes of antimicrobials as well. This study demonstrated widespread occurrence of MRCoNS on hand rails in public transport vehicles. MRSA was not detected. The recovery of methicillin-resistant staphylococci from public transport system implies a potential risk for transmission of these bacteria in an out-hospital environment.

Command Interface ASIC - Analog Interface ASIC Chip Set

NASA Technical Reports Server (NTRS)

Ruiz, Baldes; Jaffe, Burton; Burke, Gary; Lung, Gerald; Pixler, Gregory; Plummer, Joe; Katanyoutanant,, Sunant; Whitaker, William

2003-01-01

A command interface application-specific integrated circuit (ASIC) and an analog interface ASIC have been developed as a chip set for remote actuation and monitoring of a collection of switches, which can be used to control generic loads, pyrotechnic devices, and valves in a high-radiation environment. The command interface ASIC (CIA) can be used alone or in combination with the analog interface ASIC (AIA). Designed primarily for incorporation into spacecraft control systems, they are also suitable for use in high-radiation terrestrial environments (e.g., in nuclear power plants and facilities that process radioactive materials). The primary role of the CIA within a spacecraft or other power system is to provide a reconfigurable means of regulating the power bus, actuating all valves, firing all pyrotechnic devices, and controlling the switching of power to all switchable loads. The CIA is a mixed-signal (analog and digital) ASIC that includes an embedded microcontroller with supporting fault-tolerant switch control and monitoring circuitry that is capable of connecting to a redundant set of interintegrated circuit (I(sup 2)C) buses. Commands and telemetry requests are communicated to the CIA. Adherence to the I(sup 2)C bus standard helps to reduce development costs by facilitating the use of previously developed, commercially available components. The AIA is a mixed-signal ASIC that includes the analog circuitry needed to connect the CIA to a custom higher powered version of the I(sup 2)C bus. The higher-powered version is designed to enable operation with bus cables longer than those contemplated in the I(sup 2)C standard. If there are multiple higher-power I(sup 2)C-like buses, then there must an AIA between the CIA and each such bus. The AIA includes two identical interface blocks: one for the side-A I(sup 2)C clock and data buses and the other for the side B buses. All the AIAs on each side are powered from a common power converter module (PCM). Sides A and B of the I(sup 2)C buses are electrically isolated from each other (see figure). They are also isolated from the CIA by use of transformer coupling of signals between the AIA blocks and the CIA.

Comparative study of fuel cell, battery and hybrid buses for renewable energy constrained areas

NASA Astrophysics Data System (ADS)

Stempien, J. P.; Chan, S. H.

2017-02-01

Fuel cell- and battery-based public bus technologies are reviewed and compared for application in tropical urban areas. This paper scrutinizes the reported literature on fuel cell bus, fuel cell electric bus, battery electric bus, hybrid electric bus, internal combustion diesel bus and compressed natural gas bus. The comparison includes the capital and operating costs, fuel consumption and fuel cycle emissions. To the best of authors knowledge, this is the first study to holistically compare hydrogen and battery powered buses, which is the original contribution of this paper. Moreover, this is the first study to focus on supplying hydrogen and electricity from fossil resources, while including the associated emissions. The study shows that compressed natural gas and hybrid electric buses appear to be the cheapest options in terms of total cost of ownership, but they are unable to meet the EURO VI emissions' standard requirement. Only fuel cell based buses have the potential to achieve the emissions' standard when the fuel cycle based on fossil energy was considered. Fuel cell electric buses are identified as a technology allowing for the largest CO2 emission reduction, making ∼61% decrease in annual emissions possible.

Interim Evaluation Results from New Flyer/Allison Hybrid Buses at King County Metro: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandler, K.; Eberts, E.; Eudy, L.

2005-05-01

This paper prepared for the 2005 American Public Transportation Association Bus & Paratransit Conference discusses NREL/DOE evaluation of hybrid electric articulated transit buses operated by King County Metro.

Digital system bus integrity

NASA Technical Reports Server (NTRS)

Eldredge, Donald; Hitt, Ellis F.

1987-01-01

This report summarizes and describes the results of a study of current or emerging multiplex data buses as applicable to digital flight systems, particularly with regard to civil aircraft. Technology for pre-1995 and post-1995 timeframes has been delineated and critiqued relative to the requirements envisioned for those periods. The primary emphasis has been an assured airworthiness of the more prevalent type buses, with attention to attributes such as fault tolerance, environmental susceptibility, and problems under continuing investigation. Additionally, the capacity to certify systems relying on such buses has been addressed.

COMPARATIVE STUDY ON EXHAUST EMISSIONS FROM DIESEL- AND CNG-POWERED URBAN BUSES

DOE Office of Scientific and Technical Information (OSTI.GOV)

COROLLER, P; PLASSAT, G

2003-08-24

Couple years ago, ADEME engaged programs dedicated to the urban buses exhaust emissions studies. The measures associated with the reduction of atmospheric and noise pollution has particular importance in the sector of urban buses. In many cases, they illustrate the city's environmental image and contribute to reinforcing the attractiveness of public transport. France's fleet in service, presently put at about 14,000 units, consumes about 2 per cent of the total energy of city transport. It causes about 2 per cent of the HC emissions and from 4 to 6 per cent of the NOx emissions and particles. These vehicles typicallymore » have a long life span (about 15 years) and are relatively expensive to buy, about 150.000 euros per unit. Several technical solutions were evaluated to quantify, on a real condition cycle for buses, on one hand pollutants emissions, fuel consumption and on the other hand reliability, cost in real existing fleet. This paper presents main preliminary results on urban buses exhaust emission on two different cases: - existing Diesel buses, with fuel modifications (Diesel with low sulphur content), Diesel with water emulsion and bio-Diesel (30% oil ester in standard Diesel fuel); renovating CNG powered Euro II buses fleet, over representative driving cycles, set up by ADEME and partners. On these cycles, pollutants (regulated and unregulated) were measured as well as fuel consumption, at the beginning of a program and one year after to quantify reliability and increase/decrease of pollutants emissions. At the same time, some after-treatment technologies were tested under real conditions and several vehicles. Information such as fuel consumption, lubricant analysis, problem on the technology were following during a one year program. On the overall level, it is the combination of various action, pollution-reduction and renewal that will make it possible to meet the technological challenge of reducing emissions and fuel consumption by urban bus networks.« less

King County Metro Transit Hybrid Articulated Buses: Final Evaluation Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandler, K.; Walkowicz, K.

2006-12-01

Final technical report compares and evaluates new diesel and diesel hybrid-electric articulated buses operated as part of the King County Metro Transit (KC Metro) fleet in Seattle, Washington. The evaluation lasted 12 months.

Wheelchair Lifts on Transit Buses : Summary of U.S. Experience

DOT National Transportation Integrated Search

1983-01-01

The overall objective of this project was to develop information and guidance for the transit industry concerning wheelchair lifts on transit buses in the areas of lift procurement, testing and acceptance, training, and maintenance.

A Comparison of Bus Architectures for Safety-Critical Embedded Systems

NASA Technical Reports Server (NTRS)

Rushby, John; Miner, Paul S. (Technical Monitor)

2003-01-01

We describe and compare the architectures of four fault-tolerant, safety-critical buses with a view to deducing principles common to all of them, the main differences in their design choices, and the tradeoffs made. Two of the buses come from an avionics heritage, and two from automobiles, though all four strive for similar levels of reliability and assurance. The avionics buses considered are the Honeywell SAFEbus (the backplane data bus used in the Boeing 777 Airplane Information Management System) and the NASA SPIDER (an architecture being developed as a demonstrator for certification under the new DO-254 guidelines); the automobile buses considered are the TTTech Time-Triggered Architecture (TTA), recently adopted by Audi for automobile applications, and by Honeywell for avionics and aircraft control functions, and FlexRay, which is being developed by a consortium of BMW, DaimlerChrysler, Motorola, and Philips.

Studies of self-pollution in diesel school buses: methodological issues.

PubMed

Borak, Jonathan; Sirianni, Greg

2007-09-01

Considerable interest has focused on levels of exhaust emissions in the cabins of diesel-powered school buses and their possible adverse health effects. Significantly different policy and engineering issues would be raised if compelling evidence found that inc-cabin contamination was due to self-pollution from bus emissions, rather than ambient pollution, neighboring vehicles, and/or re-entrained road dust. We identified 19 reports from 11 studies that measured diesel exhaust particulate in the cabins of 58 school bus of various type. Studies were evaluated in light of their experimental design, their data quality, and their capacity to quantify self-pollution. Only one study had a true experimental design, comparing the same buses with and without emission controls, while four others used intentional tracers to quantify tail pipe and/or crankcase emissions. Although definitive data are still lacking, these studies suggest that currently available control technologies can nearly eliminate particulate self-pollution inside diesel school buses.

Contamination of public transports by Staphylococcus aureus and its carriage by biomedical students: point-prevalence, related risk factors and molecular characterization of methicillin-resistant strains.

PubMed

Mendes, Â; Martins da Costa, P; Rego, D; Beça, N; Alves, C; Moreira, T; Conceição, T; Aires-de-Sousa, M

2015-08-01

To analyse the contamination of public transports by Staphylococcus aureus and assess its carriage by biomedical students, focussing on the point-prevalence, related risk factors and molecular characterization of methicillin-resistant strains. Cross-sectional survey. Methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) isolated from handrails of buses (n = 112) and trains (n = 79) circulating in Porto and from nasal swabs of local university students (n = 475) were quantified, characterized by molecular typing methods and related to possible risk factors. The MRSA prevalence in buses (16.1%) was not significantly different from trains (8.9%). There was also no identifiable association between the counts of MSSA and MRSA in buses and trains and the number of travellers in each sampling day, specific routes (including those passing by main hospitals) or other risk factors. Of the students, 37.1% carried S. aureus, and having a part-time job or smoking were found to be risk factors for carriage. EMRSA-15 (ST22-SCCmecIVh) was the prevalent MRSA clonal lineage, found not only in the buses (n = 14) and trains (n = 2) but also in the single MRSA-carrier among the students. The characteristics of the community-associated Southwest Pacific MRSA clone were found in a single ST30-IVa isolate, which may suggest a recent SCCmec acquisition by an MSSA background in the community. The spread of EMRSA-15, a common hospital-associated lineage, among different public transports and as a nasal coloniser is of concern and warrants adequate public health control measures. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Alternative Fuels Data Center: San Diego Leads in Promoting EVs

Science.gov Websites

of a school bus Michigan Transports Students in Hybrid Electric School Buses Jan. 4, 2014 Photo of San Diego Leads in Promoting EVs to someone by E-mail Share Alternative Fuels Data Center: San Diego Leads in Promoting EVs on Facebook Tweet about Alternative Fuels Data Center: San Diego Leads in

49 CFR 579.22 - Reporting requirements for manufacturers of 100 or more buses, manufacturers of 500 or more...

Code of Federal Regulations, 2013 CFR

2013-10-01

... visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels... exterior lighting, 13 visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed... of service brake system (i.e., hydraulic or air), the information required by this subsection shall...

Accessible Bus Service in Palm Beach County, Florida

DOT National Transportation Integrated Search

1983-03-01

The Palm Beach County Transportation Authority introduced accessible fixed-route service on its countywide CoTran bus service in May 1980. CoTran provided 100% (full-fleet) accessible service, using 23 retrofitted buses and 40 new buses, all equipped...

75 FR 50958 - Federal Motor Vehicle Safety Standards; Motorcoach Definition; Occupant Crash Protection

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-18

.... Energy Absorption Capability of Seat Backs c. Retrofitting Used Buses d. School Buses VIII. Lead Time IX... the seat, reinforcing the floor, walls or other areas of the motorcoach. The final cost and weight...

77 FR 60172 - Clean Fuels Grant Program, Augmented With Discretionary Bus and Bus Facilities Program Funds

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-02

.... Grantees are reminded that the 90% provision for biodiesel buses is not available this year, as the... was highlighted in FTA's January 2012 Apportionment Notice, Section III (C). Biodiesel buses remain...

Compressed natural gas bus safety: a quantitative risk assessment.

PubMed

Chamberlain, Samuel; Modarres, Mohammad

2005-04-01

This study assesses the fire safety risks associated with compressed natural gas (CNG) vehicle systems, comprising primarily a typical school bus and supporting fuel infrastructure. The study determines the sensitivity of the results to variations in component failure rates and consequences of fire events. The components and subsystems that contribute most to fire safety risk are determined. Finally, the results are compared to fire risks of the present generation of diesel-fueled school buses. Direct computation of the safety risks associated with diesel-powered vehicles is possible because these are mature technologies for which historical performance data are available. Because of limited experience, fatal accident data for CNG bus fleets are minimal. Therefore, this study uses the probabilistic risk assessment (PRA) approach to model and predict fire safety risk of CNG buses. Generic failure data, engineering judgments, and assumptions are used in this study. This study predicts the mean fire fatality risk for typical CNG buses as approximately 0.23 fatalities per 100-million miles for all people involved, including bus passengers. The study estimates mean values of 0.16 fatalities per 100-million miles for bus passengers only. Based on historical data, diesel school bus mean fire fatality risk is 0.091 and 0.0007 per 100-million miles for all people and bus passengers, respectively. One can therefore conclude that CNG buses are more prone to fire fatality risk by 2.5 times that of diesel buses, with the bus passengers being more at risk by over two orders of magnitude. The study estimates a mean fire risk frequency of 2.2 x 10(-5) fatalities/bus per year. The 5% and 95% uncertainty bounds are 9.1 x 10(-6) and 4.0 x 10(-5), respectively. The risk result was found to be affected most by failure rates of pressure relief valves, CNG cylinders, and fuel piping.

Cutting Transportation Costs.

ERIC Educational Resources Information Center

Lewis, Barbara

1982-01-01

Beginning on the front cover, this article tells how school districts are reducing their transportation costs. Particularly effective measures include the use of computers for bus maintenance and scheduling, school board ownership of buses, and the conversion of gasoline-powered buses to alternative fuels. (Author/MLF)

The application of traffic signal preemption systems for controlling bus headways

DOT National Transportation Integrated Search

1978-04-01

This report investigates the application of selective traffic signal preemption : for controlling the headways of local service buses (buses with average time : headways of less than 10 minutes), The preemption is selective in that it is granted : to...

SunLine Transit Agency Hydrogen-Powered Transit Buses : Evaluation Results Update

DOT National Transportation Integrated Search

2007-10-01

In early 2007, the National Renewable Energy Laboratory (NREL) published a preliminary evaluation results report (January 2006 through November 2006) on hydrogen- and CNG-fueled buses operating at SunLine Transit Agency (SunLine) in Thousand Palms, C...

Moving the bus safely back into traffic : Phase II.

DOT National Transportation Integrated Search

2010-09-01

The difficulty experienced by transit buses in moving back into traffic safely from bus pullout bays has : become a serious problem due to potential hazards between buses merging from the pullout bays and : the surrounding traffic. Previous studies h...

Moving the bus safely back into traffic : phase II.

DOT National Transportation Integrated Search

2010-09-01

The difficulty experienced by transit buses in moving back into traffic safely from bus pullout bays has : become a serious problem due to potential hazards between buses merging from the pullout bays and : the surrounding traffic. Previous studies h...

Mass transit : use of alternative fuels in transit buses

DOT National Transportation Integrated Search

1999-12-14

Improving air quality in urban settings has been a long-standing national objective. Transit buses powered by diesel engines have been identified as contributors to air pollution in these areas. The Transportation Equity Act for the 21st Century (TEA...

49 CFR 392.62 - Safe operation, buses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Prohibited Practices § 392.62 Safe operation, buses. No person shall drive a bus and a motor...

Assessing the costs for hybrid versus regular transit buses : [technical brief].

DOT National Transportation Integrated Search

2012-10-01

This technical brief summarizes : information about the costs and benefits : that have been attributed to use of : hybrid transit buses as found in the : literature. Results from a demonstration : project that compared fuel economy : and emissions fo...

Materials investigation of thermal triggers used in pressure relief devices on transit buses.

DOT National Transportation Integrated Search

2003-07-01

This investigation pertains to the composition and general condition of the thermally activated trigger mechanism of Pressure Relief Devices [PRD's], safety devices used on compressed natural gas cylinders commonly used to store fuel on transit buses...

Physical characterization of fine particulate matter inside the public transit buses fueled by biodiesel in Toledo, Ohio.

PubMed

Shandilya, Kaushik K; Kumar, Ashok

2011-06-15

This study presents the physical characteristics of fine particulate matter (PM) collected inside the urban-public transit buses in Toledo, OH. These buses run on 20% biodiesel blended with ultra-low sulfur diesel (ULSD) (B20). For risk analysis, it is crucial to know the modality of the size distribution and the shape factor of PM collected inside the bus. The number-size distribution, microstructure, and aspect ratio of fine PM filter samples collected in the urban-public transit buses were measured for three years (2007-2009), using an environmental scanning electron microscope (ESEM) coupled with energy dispersive X-ray spectrometry (EDX). Only the reproducible results from repeated experiments on ESEM and size distribution obtained by the GRIMM dust monitor were used in this study. The size distribution was found bi-modal in the winter and fall months and was primarily uni-modal during spring and summer. The aspect ratio for different filter samples collected inside the bus range from 2.4 to 3.6 in average value, with standard deviation ranging from 0.9 to 7.4. The square-shaped and oblong-shaped particles represent the single inhalable particle's morphology characteristics in the air of the Toledo transit buses. Copyright © 2011 Elsevier B.V. All rights reserved.

Bluetooth wireless monitoring, diagnosis and calibration interface for control system of fuel cell bus in Olympic demonstration

NASA Astrophysics Data System (ADS)

Hua, Jianfeng; Lin, Xinfan; Xu, Liangfei; Li, Jianqiu; Ouyang, Minggao

With the worldwide deterioration of the natural environment and the fossil fuel crisis, the possible commercialization of fuel cell vehicles has become a hot topic. In July 2008, Beijing started a clean public transportation plan for the 29th Olympic games. Three fuel cell city buses and 497 other low-emission vehicles are now serving the Olympic core area and Beijing urban areas. The fuel cell buses will operate along a fixed bus line for 1 year as a public demonstration of green energy vehicles. Due to the specialized nature of fuel cell engines and electrified power-train systems, measurement, monitoring and calibration devices are indispensable. Based on the latest Bluetooth wireless technology, a novel Bluetooth universal data interface was developed for the control system of the fuel cell city bus. On this platform, a series of wireless portable control auxiliary systems have been implemented, including wireless calibration, a monitoring system and an in-system programming platform, all of which are ensuring normal operation of the fuel cell buses used in the demonstration.

Evaluation of the use of bioethanol fuelled buses based on ambient air pollution screening and on-road measurements.

PubMed

López-Aparicio, S; Hak, C

2013-05-01

Mitigation measures to reduce greenhouse gas emissions may have adverse effects on urban air quality and human exposure to harmful pollutants. The use of bioethanol fuelled vehicles is increasing worldwide and may create new undesired pollution effects. Different measurement campaigns were performed in a pilot study to contribute to the understanding of the consequences associated with the use of bioethanol blended fuel (E95) on a series of pollutants. Ambient screening measurements of NO2, O3, acetic acid, formaldehyde and acetaldehyde were performed at different urban locations, exposed and not exposed to the circulation of bioethanol buses. In addition, volatile organic compounds were measured at the exhaust pipe of a bioethanol fuelled bus, both under idling conditions (carbonyls; DNPH cartridge) and under on-road driving conditions applying online monitoring (PTR-TOF). Higher ambient acetaldehyde values were measured at locations exposed to bioethanol fuelled buses than at locations not exposed, and very high acetaldehyde and acetic acid values were measured from the exhaust pipe during driving conditions (acetaldehyde>150 ppm; acetic acid ≈ 20-30 ppm) and modelled at close distance to the bioethanol bus. Human exposure to high concentration of acetaldehyde is expected, and it may involve a significantly increased chance in developing cancer. The high concentration of acetic acid will involve odour annoyance and significant material degradation or corrosion. Copyright © 2013 Elsevier B.V. All rights reserved.

A Misleading Safety Record.

ERIC Educational Resources Information Center

Fast, Carol

1985-01-01

Comparing the safety record of school buses to that of automobiles does not account for the nonschool time when automobiles are used. Experiences where seat belts are installed in school buses show that students use them, insurance is not a problem, and cost is slight. (MLF)

Hickam Air Force Base Fuel Cell Vehicles : Early Implementation Experience

DOT National Transportation Integrated Search

2008-07-01

This report describes operations at Alameda-Contra Costa Transit District (AC Transit) for three prototype fuel cell buses and six diesel buses operating from the same location. This is the third evaluation report for this site, and it describes new ...

Switch to Diesels Cuts Transportation Costs.

ERIC Educational Resources Information Center

Meyer, Kay

1982-01-01

Since the acquisition of diesel-powered school buses for the Half Hollow Hills (New York) School District, fuel efficiency has doubled. This has helped cover the costs of refurbishing older buses and establishing a more sophisticated shop operation and more efficient recordkeeping. (Author/MLF)

Regulation of private school buses in Virginia : results of a study mandated by the NTSB.

DOT National Transportation Integrated Search

1987-01-01

In response to major accidents in Florida and Alabama involving privately-owned and privately-operated school buses, the National Transportation Safety Board (NTSB) issued three safety recommendations to the governors of all states and required each ...

Tri-wheeled scooters transported on buses and vans : assessment of securement restraint issues

DOT National Transportation Integrated Search

2005-10-01

Under the Americans with Disabilities Act (ADA) of 1990, all "common wheelchairs and mobility aids", including tri-wheeled scooters, must be accommodated on buses and vans used in public transit service. Several transit systems have recently expresse...

National Fuel Cell Bus Program : Accelerated Testing Report, AC Transit

DOT National Transportation Integrated Search

2009-01-01

This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006 compared to similar diesel buses operating from the same depot. This evaluation report includes results from November 2007 throu...

Standardization of availability, location and use of safety equipment on urban transit buses

DOT National Transportation Integrated Search

1996-03-01

This document represents the conclusion of a project undertaken to identify guidelines which will correct the problems encountered by rescue forces while attempting to gain entry to, shut down, and evacuate urban transit buses involved in an emergenc...

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

PubMed

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.

Thermographic inspection and quality assurance of energy conservation procedures for electric buses

NASA Astrophysics Data System (ADS)

Fennell, Henri C.

1998-03-01

Electric buses are one of the solutions for improving air quality in our cities. Many states are adopting 'no new diesel bus' policies, thus increasing the pressure to develop alternative vehicles. The fledgling electric vehicle technology suffers from acceptance problems by major transit authorities due primarily to limited travel range from each battery charge. Utilizing electric buses in the Northeast has the added problem of maintaining an adequate cabin temperature without the availability of heat from a diesel motor. Heating the passenger cabin with an electric heater which draws from the batteries' stored energy significantly reduces the already modest range of these vehicles; therefore, energy conservation measures play an important role in allowing electric vehicles to provide practical transit services. IR thermography, in conjunction with air leakage pressurization diagnostics, has proven to be an excellent tool for developing energy-efficient bus designs as well as a valuable in-service performance testing method. This paper is based on tests performed on several Advanced Vehicle Systems, Inc. electric buses during research performed under Northeast Alternative Vehicle Consortium and Defense Advanced Research Projects Agency grants. The work demonstrates the thermographic methods used and the real- world increased performance of retrofitted and newly designed buses resulting from this initial Portland Transit retrofit project and in a follow-up project to develop a cold weather specification for a new generation of electric buses. Early diagnostic and new-technology follow-up thermographic performance testing was paralleled by energy modeling of early baseline and re-designed vehicles. Modeling and performance data are included. As a result of this research, thermography, air-leakage/pressurization testing, and fog analysis techniques are now being used regularly in research and development and quality assurance procedures by electric bus manufacturers.

Relative importance of school bus-related microenvironments to children's pollutant exposure.

PubMed

Behrentz, Eduardo; Sabin, Lisa D; Winer, Arthur M; Fitz, Dennis R; Pankratz, David V; Colome, Steven D; Fruin, Scott A

2005-10-01

Real-time concentrations of black carbon, particle-bound polycyclic aromatic hydrocarbons, nitrogen dioxide, and fine particulate counts, as well as integrated and real-time fine particulate matter (PM2.5) mass concentrations were measured inside school buses during long commutes on Los Angeles Unified School District bus routes, at bus stops along the routes, at the bus loading/unloading zone in front of the selected school, and at nearby urban "background" sites. Across all of the pollutants, mean concentrations during bus commutes were higher than in any other microenvironment. Mean exposures (mean concentration times time spent in a particular microenvironment) in bus commutes were between 50 and 200 times greater than those for the loading/unloading microenvironment, and 20-40 times higher than those for the bus stops, depending on the pollutant. Although the analyzed school bus commutes represented only 10% of a child's day, on average they contributed one-third of a child's 24-hr overall black carbon exposure during a school day. For species closely related to vehicle exhaust, the within- cabin exposures were generally dominated by the effect of surrounding traffic when windows were open and by the bus's own exhaust when windows were closed. Low-emitting buses generally exhibited high concentrations only when traveling behind a diesel vehicle, whereas high-emitting buses exhibited high concentrations both when following other diesel vehicles and when idling without another diesel vehicle in front of the bus. To reduce school bus commute exposures, we recommend minimizing commute times, avoiding caravanning with other school buses, using the cleanest buses for the longest bus routes, maintaining conventional diesel buses to eliminate visible emissions, and transitioning to cleaner fuels and advanced particulate control technologies as soon as possible.

49 CFR 579.22 - Reporting requirements for manufacturers of 100 or more buses, manufacturers of 500 or more...

Code of Federal Regulations, 2014 CFR

2014-10-01

... train, 11 electrical, 12 exterior lighting, 13 visibility, 14 air bags, 15 seat belts, 16 structure, 17... visibility, 14 air bags, 15 seat belts, 16 structure, 17 latch, 18 vehicle speed control, 19 tires, 20 wheels... manufactured and available with more than one type of service brake system (i.e., hydraulic or air), the...

Computer Simulations and Literature Survey of Continuously Variable Transmissions for Use in Buses

DOT National Transportation Integrated Search

1981-12-01

Numerous studies have been conducted on the concept of flywheel energy storage for buses. Flywheel systems require a continuously variable transmission (CVT) of some type to transmit power between the flywheel and the drive wheels. However, a CVT can...

Diesel Powered School Buses: An Update.

ERIC Educational Resources Information Center

Gresham, Robert

1984-01-01

Because diesel engines are more economical and longer-lasting than gasoline engines, school districts are rapidly increasing their use of diesel buses. Dependence on diesel power, however, entails vulnerability to cost increases due to the unreliability of crude oil supplies and contributes to air pollution. (MCG)

Life Cycle Assessment of Diesel and Electric Public Transportation Buses

EPA Science Inventory

The Clean Air Act identifies diesel powered motor vehicles, including transit buses, as significant sources of several criteria pollutants which contribute to ground level ozone formation or smog. The effects of air pollution in urban areas are often more significant due to con...

Oregon bus riders blast into orbit; Satellite technology to help keep Portland buses on schedule

DOT National Transportation Integrated Search

1994-06-22

Fairchild Space & Defense Corporation (Fairchild) : announced today that it was awarded a first of its kind $5 million contract by the public transit agency : serving Portland Oregon to equip 740 buses and paratransit vehicles with sophisticated sate...

Busing and Redistricting in the 'Down-Up' Era.

ERIC Educational Resources Information Center

Freeman, David N.

1987-01-01

Besides redistricting problems engendered by higher elementary school enrollments (and decreasing secondary enrollments), school administrators face student transport challenges. Acquiring new routes and larger buses could be costly. This article advances computerized systems as the most cost-effective way to optimize routes and manage…

White Attitudes toward Busing: Segregation and the Life Cycle.

ERIC Educational Resources Information Center

Edari, Ronald S.

1979-01-01

Factors involved in the determination of White attitudes toward busing are discussed. The term White flight is considered a euphemism for the process in which the responsibility for housing discrimination is shifted from the structure of the capitalist system to White community residents. (RLV)

Ultrafine particle emissions by in-use diesel buses of various generations at low-load regimes

NASA Astrophysics Data System (ADS)

Tartakovsky, L.; Baibikov, V.; Comte, P.; Czerwinski, J.; Mayer, A.; Veinblat, M.; Zimmerli, Y.

2015-04-01

Ultrafine particles (UFP) are major contributors to air pollution due to their easy gas-like penetration into the human organism, causing adverse health effects. This study analyzes UFP emissions by buses of different technologies (from Euro II till Euro V EEV - Enhanced Environmentally-friendly Vehicle) at low-load regimes. Additionally, the emission-reduction potential of retrofitting with a diesel particle filter (DPF) is demonstrated. A comparison of the measured, engine-out, particle number concentrations (PNC) for buses of different technological generations shows that no substantial reduction of engine-out emissions at low-load operating modes is observed for newer bus generations. Retrofitting the in-use urban and interurban buses of Euro II till Euro IV technologies by the VERT-certified DPF confirmed its high efficiency in reduction of UFP emissions. Particle-count filtration efficiency values of the retrofit DPF were found to be extremely high - greater than 99.8%, similar to that of the OEM filter in the Euro V bus.

King County Metro Battery Electric Bus Demonstration: Preliminary Project Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

The U.S. Federal Transit Administration (FTA) funds a variety of research projects that support the commercialization of zero-emission bus technology. To evaluate projects funded through these programs, FTA has enlisted the help of the National Renewable Energy Laboratory (NREL) to conduct third-party evaluations of the technologies deployed under the FTA programs. NREL works with the selected agencies to evaluate the performance of the zero-emission buses compared to baseline conventional buses in similar service. The evaluation effort will advance the knowledge base of zero-emission technologies in transit bus applications and provide 'lessons learned' to aid other fleets in incrementally introducing nextmore » generation zero-emission buses into their operations. This report provides preliminary performance evaluation results from a demonstration of three zero-emission battery electric buses at King County Metro in King County, Washington. NREL developed this preliminary results report to quickly disseminate evaluation results to stakeholders. Detailed evaluation results will be published in future reports.« less

Party on wheels: mobile party spaces in the Norwegian high school graduation celebration.

PubMed

Fjaer, Eivind Grip; Pedersen, Willy; Sandberg, Sveinung

2016-06-01

Research on partying and nightlife often emphasizes commercial control while overlooking participants' creativity and agency. Due to their age, appearance and transgressive partying, participants in the Norwegian high school graduation celebration have limited access to bars and pubs in the ordinary night-time economy. To create alternative party spaces under their own control they utilize the spatial opportunities offered by automobility. Groups of students get together many years in advance and buy old buses which they refurbish to become rolling nightclubs that enable them to 'transcend space' through partying while on the move. These mobile party spaces provide a material and symbolic centre of communion and a tight space for physical assembly that enhances the production of intense positive emotions. In a cat-and-mouse game with the police, the buses provide a sense of nomadic autonomy, and enable participants to drink heavily for days on end. The study examines how youth may creatively zone their own party spaces within the context of automobility and how these mobile spaces again shape the partying that goes on within them. While this party practice opens up for autonomy, creativity and social transgressions reminiscent of liminal phases or carnivals, at a deeper level participants clearly reproduce class-based differences and exaggerate conventional practices and symbols. © London School of Economics and Political Science 2016.

North Carolina school bush crash data and issues related to seat belts on large school buses

DOT National Transportation Integrated Search

1999-04-01

School bus transportation and safety is a very serious and sometimes controversial and : emotional issue. Although school buses have been shown to be a very safe form of : transportation, many parents and safety advocates question the absence of seat...

Characterization and speciation of fine particulate matter inside the public transport buses running on bio-diesel.

DOT National Transportation Integrated Search

2009-09-01

Air pollution with respect to particulate matter was investigated in Toledo, Ohio, USA, a : city of approximately 300,000, in 2009. Two study buses were selected to reflect typical : exposure conditions of passengers while traveling in the bus. Monit...

Design Guidelines for Bus Transit Systems Using Liquefied Petroleum Gas (LPG) as an Alternative Fuel.

DOT National Transportation Integrated Search

1996-09-01

The use of alternative fuels to power transit buses is steadily increasing. Several fuels, including Liquefied Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Methanol/Ethanol, are already being used in buses. At present, there do not exist co...

Santa Clara Valley Transportation Authority and San Mateo County Transit District Fuel Cell Transit Buses : Evaluation Results

DOT National Transportation Integrated Search

2006-11-23

This report provides evaluation results for prototype fuel cell transit buses operating at Santa Clara Valley Transportation Authority (VTA) in San Jose, California. San Mateo County Transit District (SamTrans) in San Carlos, California, is a partner...

Santa Clara Valley Transportation Authority and San Mateo County Transit District Fuel Cell Transit Buses : Preliminary Evaluation Results

DOT National Transportation Integrated Search

2006-03-23

This report provides preliminary results from an evaluation of prototype fuel cell transit buses operating at Santa Clara Valley Transportation Authority (VTA) in San Jose, California. San Mateo County Transit District (SamTrans) in San Carlos, Calif...

78 FR 35354 - Supreme Indiana Operations, Inc., Grant of Petition for Decision of Inconsequential Noncompliance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-12

... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration [Docket No. NHTSA-2012... Noncompliance AGENCY: National Highway Traffic Safety Administration, DOT. ACTION: Grant of Petition. SUMMARY... Startrans trucks, buses, and multifunction school activity buses (MFSAB) manufactured from 2006 through 2011...

77 FR 16893 - Supreme Indiana Operations, Inc., Receipt of Petition for Decision of Inconsequential Noncompliance

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-22

... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration [Docket No. NHTSA-2012... Noncompliance AGENCY: National Highway Traffic Safety Administration, DOT. ACTION: Receipt of petition. SUMMARY... Startrans trucks, buses, and multifunction school activity buses (MFSAB) manufactured from 2006 through 2011...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2014 CFR

2014-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2012 CFR

2012-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2011 CFR

2011-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2013 CFR

2013-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

Seat Belts in School Buses: A Technical Analysis of the Literature.

ERIC Educational Resources Information Center

Splaine, Pam; Frankel, Steven M.

This report, prepared for the Montgomery County (Maryland) Public Schools superintendent and board members, identifies the questions concerning seat belt use in school buses, examines relevant literature, and draws some conclusions. According to the literature, seat belts are one of many alternative and interdependent safety devices built into…

49 CFR 661.12 - Certification requirement for procurement of buses, other rolling stock and associated equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., other rolling stock and associated equipment. 661.12 Section 661.12 Transportation Other Regulations... associated equipment. If buses or other rolling stock (including train control, communication, and traction power equipment) are being procured, the appropriate certificate as set forth below shall be completed...

Alternative Fuels Data Center: Minnesota School District Finds Cost

Science.gov Websites

Savings, Cold-Weather Reliability with Propane Buses Minnesota School District Finds Cost Center: Minnesota School District Finds Cost Savings, Cold-Weather Reliability with Propane Buses on Facebook Tweet about Alternative Fuels Data Center: Minnesota School District Finds Cost Savings, Cold

Alternative Fuels Data Center: Mesa Unified School District Reaps Economic

Science.gov Websites

and Environmental Benefits with Propane Buses Mesa Unified School District Reaps Economic and School District Reaps Economic and Environmental Benefits with Propane Buses on Facebook Tweet about Alternative Fuels Data Center: Mesa Unified School District Reaps Economic and Environmental Benefits with

Crashworthiness of Restraints for Physically Disabled Children in Buses.

ERIC Educational Resources Information Center

Seeger, Barry R.; Caudrey, David J.

1983-01-01

Seven design principles identified from research as crashworthy for transporting disabled persons in buses are listed, and survey results of transportation of 161 disabled children in Australia are discussed relative to the design principles. Findings are discussed and recommendations made to correct deviations, such as absence of lapbelts. (MC)

BIODIESEL AS A SUSTAINABLE ALTERNATIVE TO PETROLEUM DIESEL IN SCHOOL BUSES

EPA Science Inventory

Diesel exhaust is potentially harmful to human health and is a significant air pollutant due to its composition of harmful chemical substances and impact on climate. One of the many current uses of diesel fuel in rural environments is in school buses; however, few studies hav...

77 FR 24362 - Airworthiness Directives; Bombardier, Inc. Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-24

... was prompted by reports of the air driven generator (ADG) failing to power essential buses during... essential buses which, in the event of an emergency, could prevent continued safe flight. DATES: This AD... prevent continued safe flight. This [TCCA] directive mandates the replacement of the ADG GCU. You may...

Life-cycle energy and emissions inventories for motorcycles, diesel automobiles, school buses, electric buses, Chicago rail, and New York City rail

DOT National Transportation Integrated Search

2009-05-01

The development of life-cycle energy and emissions factors for passenger transportation modes : is critical for understanding the total environmental costs of travel. Previous life-cycle studies : have focused on the automobile given its dominating s...

Crash problem definition and safety benefits methodology for stability control for single-unit medium and heavy trucks and large-platform buses

DOT National Transportation Integrated Search

2009-10-01

This report presents the findings of a comprehensive engineering analysis of electronic stability control (ESC) and roll stability control (RSC) systems for single-unit medium and heavy trucks and large-platform buses. This report details the applica...

School Bus Safety. An AS&U Roundtable.

ERIC Educational Resources Information Center

American School and University, 1985

1985-01-01

A roundtable discussion of the issue of seat belts in school buses features United States Representative Peter H. Kostmayer, who has introduced a bill providing incentive grants to states to adopt and enforce laws requiring the use of seat belts in new school buses; three bus manufacturing executives; and two educators. (MLF)

Recommendations for yield-to-bus traffic control devices and bus pullout bays design characteristics : [research summary].

DOT National Transportation Integrated Search

2013-04-01

Bus pullout bays are being installed increasingly : on Floridas roads as a safety factor and so that : stopped buses do not impede traffic. In Florida, : state law requires car drivers to yield to buses : when a bus needs to reenter the roadway af...

77 FR 7525 - Revision of Class D and Class E Airspace; Hawthorne, CA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-13

...-0610; Airspace Docket No. 11-AWP-10] Revision of Class D and Class E Airspace; Hawthorne, CA AGENCY... Part 71.1. The Class D airspace and Class E airspace designations listed in this document will be... CFR) Part 71 by revising Class D airspace and Class E surface airspace designated as an extension to...

Medium Truck Duty Cycle Data from Real-World Driving Environments: Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lascurain, Mary Beth; Franzese, Oscar; Capps, Gary J

2012-11-01

Since the early part of the 20th century, the US trucking industry has provided a safe and economical means of moving commodities across the country. At present, nearly 80% of US domestic freight movement involves the use of trucks. The US Department of Energy (DOE) is spearheading a number of research efforts to improve heavy vehicle fuel efficiencies. This includes research in engine technologies (including hybrid and fuel cell technologies), lightweight materials, advanced fuels, and parasitic loss reductions. In addition, DOE is developing advanced tools and models to support heavy vehicle research and is leading the 21st Century Truck Partnershipmore » and the SuperTruck development effort. Both of these efforts have the common goal of decreasing the fuel consumption of heavy vehicles. In the case of SuperTruck, a goal of improving the overall freight efficiency of a combination tractor-trailer has been established. This Medium Truck Duty Cycle (MTDC) project is a critical element in DOE s vision for improved heavy vehicle energy efficiency; it is unique in that there is no other existing national database of characteristic duty cycles for medium trucks based on collecting data from Class 6 and 7 vehicles. It involves the collection of real-world data on medium trucks for various situational characteristics (e.g., rural/urban, freeway/arterial, congested/free-flowing, good/bad weather) and looks at the unique nature of medium trucks drive cycles (stop-and-go delivery, power takeoff, idle time, short-radius trips). This research provides a rich source of data that can contribute to the development of new tools for FE and modeling, provide DOE a sound basis upon which to make technology investment decisions, and provide a national archive of real-world-based medium-truck operational data to support energy efficiency research. The MTDC project involved a two-part field operational test (FOT). For the Part-1 FOT, three vehicles each from two vocations (urban transit and dry-box delivery) were instrumented for the collection of one year of operational data. The Part-2 FOT involved the towing and recovery and utility vocations for a second year of data collection. The vehicles that participated in the MTDC project did so through gratis partnerships in return for early access to the results of this study. Partnerships such as these are critical to FOTs in which real-world data is being collected. In Part 1 of the project, Oak Ridge National Laboratory (ORNL) established partnerships with the H.T. Hackney Company (HTH), one of the largest wholesale distributors in the country, distributing products to 21 states; and with Knoxville Area Transit (KAT), the city of Knoxville s transit system, which operates across Knoxville and parts of Knox County. These partnerships and agreements provided ORNL access to three Class-7 day-cab tractors that regularly haul 28 ft pup trailers (HTH) and three Class-7 buses for the collection of duty cycle data. In addition, ORNL collaborated with the Federal Motor Carrier Safety Administration (FMCSA) to determine if there were possible synergies between this duty cycle data collection effort and FMCSA s need to learn more about the operation and duty cycles of medium trucks. FMCSA s primary interest was in collecting safety data relative to the driver, carrier, and vehicle. In Part 2 of the project, ORNL partnered with the Knoxville Utilities Board, which made available three Class-8 trucks. Fountain City Wrecker Service was also a Part 2 partner, providing three Class-6 rollback trucks. In order to collect the duty cycle and safety-related data, ORNL developed a data acquisition system (DAS) that was placed on each test vehicle. Each signal recorded in this FOT was collected by means of one of the instruments incorporated into each DAS. Other signals were obtained directly from the vehicle s J1939 and J1708 data buses. A VBOX II Lite collected information available from a global positioning system (GPS), including speed, acceleration, and spatial location information at a rate of 5 Hz for the Part 1 FOT. For the Part 2 FOT, this information was obtained from DAS-based GPS instrumentation. The Air-Weigh LoadMaxx, a self-weighing system that determines the vehicle s gross weight by means of pressure transducers, was used to collect vehicle payload information for the combination, urban transit, and towing and recovery vehicles. A cellular modem, the Raven X EVDO V4221, facilitated the communication between the eDAQ-lite (the data collection engine of the system) and the user. The modem functioned as a wireless gateway, allowing data retrievals and system checks to be performed remotely. Also, in partnership with FMCSA, two additional safety sensors were installed on the combination vehicles: the MGM e-Stroke brake monitoring system and the Tire SafeGuard tire pressure monitoring system. All of these sensors posted data to the J1939 data bus, enabling the signals to be read withou...« less

Reorganization of equivalence classes: effects of preliminary training and meaningful stimuli.

PubMed

Arntzen, Erik; Nartey, Richard K; Fields, Lanny

2018-05-01

In Condition 1, adults learned the baseline relations for the three equivalence classes A1-B1-C1-D1-E1, A2-B2-C2-D2-E2, and A3-B3-C3-D3-E3. Classes contained abstract shapes in the ABS and four preliminary training groups. Each class in the PIC group contained one picture and four abstract shapes. Before class formation for four other groups, preliminary training involved establishing identity (CC) or arbitrary (CX) relations either with or without a delay. Without preliminary training, classes formed with low and high likelihoods in the ABS and PIC groups, respectively. Preliminary training with no delay produced modest increases in class formation, while preliminary training with delay produced large increases in class formation. Condition 2 replicated Condition 1 but with training of reassigned BC and CD relations that linked C from one class to B and D from another class: B1-C2, B2-C3, B3-C1, C2-D1, C3-D2, and C1-D3. Subsequent tests assessed the emergence of the reorganized classes A1-B1-C2-D1-E1, A2-B2-C3-D2-E2, and A3-B3-C1-D3-E3. All preliminary training procedures increased likelihood of forming the reorganized classes to the level seen in the PIC group. Greater gains were produced by preliminary training with no delays than with delays. Test performances also showed how preliminary training influenced baseline acquisition speed and participant-defined relations. © 2018 Society for the Experimental Analysis of Behavior.

Fuel Cell Buses in U.S. Transit Fleets: Current Status 2015

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudy, Leslie; Post, Matthew; Gikakis, Christina

This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. Various stakeholders, including FCEB developers, transit agencies, and system integrators, have expressed the value of this annual status report, which provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. The annual status report tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. Themore » 2015 summary results primarily focus on the most recent year for each demonstration, from August 2014 through July 2015. The results for these buses account for more than 1,045,000 miles traveled and 83,000 hours of fuel cell power system operation. The primary results presented in the report are from two demonstrations of fuel-cell-dominant bus designs: the Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California and the American Fuel Cell Bus Project at SunLine Transit Agency in California.« less

Itinerant vending of medicines inside buses in Nigeria: vending strategies, dominant themes and medicine-related information provided.

PubMed

Yusuff, Kazeem B; Wassi Sanni, Abd'

2011-07-01

To determine vending strategies and marketing themes employed by itinerant bus vendors, and assess the accuracy and completeness of information provided on medicines being sold in an urban setting in Nigeria. Cross-sectional study and content analysis of itinerant vending of medicines inside buses recorded with a mobile telephone on purposively selected routes in a mega city with an estimated 18 million residents in southwestern Nigeria over a 2-month period. Two coders independently assessed 192 vending episodes by 56 vendors for 147 OTC and prescription medicines. Inter-rater reliability (Gwet AC1 =0.924; p<0.0001). Fourteen thousands and four hundred potential consumers encountered 192 recorded episodes of vending of medicines inside 192 buses within the study periods. Forty-four (78•5%) of the 56 vendors were females in the 30-45 years age bracket, were mostly (75%) attired in the local 'Iro and Buba' Ankara fabric and showed laminated identity cards (97.5%) issued by the local association for 'marketers' of medicines inside buses, markets, and motor parks. Of the 14400 consumers encountered inside buses during the study period, between 6.7% and 48.3% purchased the medicines promoted. Prayers against death from road traffic accidents and diseases of physical and / or meta-physical origins were the most frequently used (76•8%) ice-breaking opening statement / strategy to gain consumers' attention. Hematinics, multi-vitamins, simple analgesic, NSAIDs and corticosteroids were the most frequently vended medicines. Consumers' enquiries were related to dosing for children (51.8%), elderly (28.6%), and pregnancy (52.7%); and contra-indications during pregnancy (8.9%). Factual medicines information such as dose, frequency, potential side effects and contra-indications were not provided in majority of vending episodes. Itinerant vending of medicines and the use of misleading and melodramatic themes to secure high consumer patronage appear considerable in Nigeria. Majority of the vendors did not correctly respond to consumers medicine-related enquiries, or provide detailed factual medicines information to guide appropriate use. These misleading promotional activities could potentially encourage inappropriate purchase and probable self-medication by consumers.

Itinerant vending of medicines inside buses in Nigeria: vending strategies, dominant themes and medicine-related information provided

PubMed Central

Yusuff, Kazeem B.; Wassi Sanni, Abd’

Objective To determine vending strategies and marketing themes employed by itinerant bus vendors, and assess the accuracy and completeness of information provided on medicines being sold in an urban setting in Nigeria. Methods Cross-sectional study and content analysis of itinerant vending of medicines inside buses recorded with a mobile telephone on purposively selected routes in a mega city with an estimated 18 million residents in southwestern Nigeria over a 2-month period. Two coders independently assessed 192 vending episodes by 56 vendors for 147 OTC and prescription medicines. Inter-rater reliability (Gwet AC1 =0.924; p<0.0001). Results Fourteen thousands and four hundred potential consumers encountered 192 recorded episodes of vending of medicines inside 192 buses within the study periods. Forty-four (78•5%) of the 56 vendors were females in the 30-45 years age bracket, were mostly (75%) attired in the local ‘Iro and Buba’ Ankara fabric and showed laminated identity cards (97.5%) issued by the local association for ‘marketers’ of medicines inside buses, markets, and motor parks. Of the 14400 consumers encountered inside buses during the study period, between 6.7% and 48.3% purchased the medicines promoted. Prayers against death from road traffic accidents and diseases of physical and / or meta-physical origins were the most frequently used (76•8%) ice-breaking opening statement / strategy to gain consumers’ attention. Hematinics, multi-vitamins, simple analgesic, NSAIDs and corticosteroids were the most frequently vended medicines. Consumers’ enquiries were related to dosing for children (51.8%), elderly (28.6%), and pregnancy (52.7%); and contra-indications during pregnancy (8.9%). Factual medicines information such as dose, frequency, potential side effects and contra-indications were not provided in majority of vending episodes. Conclusions Itinerant vending of medicines and the use of misleading and melodramatic themes to secure high consumer patronage appear considerable in Nigeria. Majority of the vendors did not correctly respond to consumers medicine-related enquiries, or provide detailed factual medicines information to guide appropriate use. These misleading promotional activities could potentially encourage inappropriate purchase and probable self-medication by consumers. PMID:24367466

Measuring In-Cabin School Bus Tailpipe and Crankcase PM2.5: A New Dual Tracer Method.

PubMed

Ireson, Robert G; Ondov, John M; Zielinska, Barbara; Weaver, Christopher S; Easter, Michael D; Lawson, Douglas R; Hesterberg, Thomas W; Davey, Mark E; Liu, L-J Sally

2011-05-01

Exposures of occupants in school buses to on-road vehicle emissions, including emissions from the bus itself, can be substantially greater than those in outdoor settings. A dual tracer method was developed and applied to two school buses in Seattle in 2005 to quantify in-cabin fine particulate matter (PM 2.5 ) concentrations attributable to the buses' diesel engine tailpipe (DPM tp ) and crankcase vent (PM ck ) emissions. The new method avoids the problem of differentiating bus emissions from chemically identical emissions of other vehicles by using a fuel-based organometallic iridium tracer for engine exhaust and by adding deuterated hexatriacontane to engine oil. Source testing results showed consistent PM:tracer ratios for the primary tracer for each type of emissions. Comparisons of the PM:tracer ratios indicated that there was a small amount of unburned lubricating oil emitted from the tailpipe; however, virtually no diesel fuel combustion products were found in the crankcase emissions. For the limited testing conducted here, although PM ck emission rates (averages of 0.028 and 0.099 g/km for the two buses) were lower than those from the tailpipe (0.18 and 0.14 g/km), in-cabin PM ck concentrations averaging 6.8 μg/m 3 were higher than DPM tp (0.91 μg/m 3 average). In-cabin DPM tp and PM ck concentrations were significantly higher with bus windows closed (1.4 and 12 μg/m 3 , respectively) as compared with open (0.44 and 1.3 μg/m 3 , respectively). For comparison, average closed- and open-window in-cabin total PM 2.5 concentrations were 26 and 12 μg/m 3 , respectively. Despite the relatively short in-cabin sampling times, very high sensitivities were achieved, with detection limits of 0.002 μg/m 3 for DPM tp and 0.05 μg/m 3 for PM ck . [Box: see text].

Characteristics of cabin air quality in school buses in Central Texas

NASA Astrophysics Data System (ADS)

Rim, Donghyun; Siegel, Jeffrey; Spinhirne, Jarett; Webb, Alba; McDonald-Buller, Elena

This study assessed in-cabin concentrations of diesel-associated air pollutants in six school buses with diesel engines during a typical route in suburban Austin, Texas. Air exchange rates measured by SF 6 decay were 2.60-4.55 h -1. In-cabin concentrations of all pollutants measured exhibited substantial variability across the range of tests even between buses of similar age, mileage, and engine type. In-cabin NO x concentrations ranged from 44.7 to 148 ppb and were 1.3-10 times higher than roadway NO x concentrations. Mean in-cabin PM 2.5 concentrations were 7-20 μg m -3 and were generally lower than roadway levels. In-cabin concentrations exhibited higher variability during cruising mode than frequent stops. Mean in-cabin ultrafine PM number concentrations were 6100-32,000 particles cm -3 and were generally lower than roadway levels. Comparison of median concentrations indicated that in-cabin ultrafine PM number concentrations were higher than or approximately the same as the roadway concentrations, which implied that, by excluding the bias caused by local traffic, ultrafine PM levels were higher in the bus cabin than outside of the bus. Cabin pollutant concentrations on three buses were measured prior to and following the phased installation of a Donaldson Spiracle Crankcase Filtration System and a Diesel Oxidation Catalyst. Following installation of the Spiracle, the Diesel Oxidation Catalyst provided negligible or small additional reductions of in-cabin pollutant levels. In-cabin concentration decreases with the Spiracle alone ranged from 24 to 37% for NO x and 26 to 62% and 6.6 to 43% for PM 2.5 and ultrafine PM, respectively. Comparison of the ranges of PM 2.5 and ultrafine PM variations between repetitive tests suggested that retrofit installation could not always be conclusively linked to the decrease of pollutant levels in the bus cabin.

Measuring in-cabin school bus tailpipe and crankcase PM2.5: a new dual tracer method.

PubMed

Ireson, Robert G; Ondov, John M; Zielinska, Barbara; Weaver, Christopher S; Easter, Michael D; Lawson, Douglas R; Hesterberg, Thomas W; Davey, Mark E; Liu, L-J Sally

2011-05-01

Exposures of occupants in school buses to on-road vehicle emissions, including emissions from the bus itself, can be substantially greater than those in outdoor settings. A dual tracer method was developed and applied to two school buses in Seattle in 2005 to quantify in-cabin fine particulate matter (PM2.5) concentrations attributable to the buses' diesel engine tailpipe (DPMtp) and crankcase vent (PMck) emissions. The new method avoids the problem of differentiating bus emissions from chemically identical emissions of other vehicles by using a fuel-based organometallic iridium tracer for engine exhaust and by adding deuterated hexatriacontane to engine oil. Source testing results showed consistent PM:tracer ratios for the primary tracer for each type of emissions. Comparisons of the PM:tracer ratios indicated that there was a small amount of unburned lubricating oil emitted from the tailpipe; however, virtually no diesel fuel combustion products were found in the crankcase emissions. For the limited testing conducted here, although PMck emission rates (averages of 0.028 and 0.099 g/km for the two buses) were lower than those from the tailpipe (0.18 and 0.14 g/km), in-cabin PMck concentrations averaging 6.8 microg/m3 were higher than DPMtp (0.91 microg/m3 average). In-cabin DPMtp and PMck concentrations were significantly higher with bus windows closed (1.4 and 12 microg/m3, respectively) as compared with open (0.44 and 1.3 microg/m3, respectively). For comparison, average closed- and open-window in-cabin total PM2.5 concentrations were 26 and 12 microg/m3, respectively. Despite the relatively short in-cabin sampling times, very high sensitivities were achieved, with detection limits of 0.002 microg/m3 for DPMtp and 0.05 microg/m3 for PMck.

Combined Quarterly Technical Report Number 25. SATNET Development and Operation, Pluribus Satellite IMP Development, Remote Site Maintenance, Internet Operations and Maintenance, Mobile Access Terminal Network, TCP for the HP3000, TCP for VAX-UNIX.

DTIC Science & Technology

1982-05-01

the F-Bus. The two possible SuperSUE I Pollers, SSPE and SSPF, are on the E and F buses, respectively. P13 is the P13 Poller. A PSAT will have at... SSPE and SSPF are again the two possible SuperSUE Pollers. HPOL is an abbrevation for the HINPOL and HOUTPOL routines. -44- jReport No. 5003 Bolt...I IS I E-Bus,F-Bus I E-Bus Only I F-Bus only I s -- - - - - - - - - - - - - - - - - -- - - - - - P E-Bus ISMIE/ SSPE ISMIE/ SSPE ISMIF/SSPF IF-Bu3

Assessment of GHG mitigation and CDM technology in urban transport sector of Chandigarh, India.

PubMed

Bhargava, Nitin; Gurjar, Bhola Ram; Mor, Suman; Ravindra, Khaiwal

2018-01-01

The increase in number of vehicles in metropolitan cities has resulted in increase of greenhouse gas (GHG) emissions in urban environment. In this study, emission load of GHGs (CO, N 2 O, CO 2 ) from Chandigarh road transport sector has been estimated using Vehicular Air Pollution Inventory (VAPI) model, which uses emission factors prevalent in Indian cities. Contribution of 2-wheelers (2-w), 3-wheelers (3-w), cars, buses, and heavy commercial vehicles (HCVs) to CO, N 2 O, CO 2 , and total GHG emissions was calculated. Potential for GHG mitigation through clean development mechanism (CDM) in transport sector of Chandigarh under two scenarios, i.e., business as usual (BAU) and best estimate scenario (BES) using VAPI model, has been explored. A major contribution of GHG load (~ 50%) in Chandigarh was from four-wheelers until 2011; however, it shows a declining trend after 2011 until 2020. The estimated GHG emission from motor vehicles in Chandigarh has increased more than two times from 1065 Gg in 2005 to 2486 Gg by 2011 and is expected to increase to 4014 Gg by 2020 under BAU scenario. Under BES scenario, 30% of private transport has been transformed to public transport; GHG load was possibly reduced by 520 Gg. An increase of 173 Gg in GHGs load is projected from additional scenario (ADS) in Chandigarh city if all the diesel buses are transformed to CNG buses by 2020. Current study also offers potential for other cities to plan better GHG reduction strategies in transport sector to reduce their climate change impacts.

45 CFR 1310.12 - Required use of School Buses or Allowable Alternate Vehicles.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 4 2014-10-01 2014-10-01 false Required use of School Buses or Allowable Alternate Vehicles. 1310.12 Section 1310.12 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR...

Transportation of Wheelchair Seated Students in School Buses: A Review of State Policy

ERIC Educational Resources Information Center

Moore, Britta; Fuhrman, Susan; Karg, Patricia

2010-01-01

This study quantitatively reviews publicly available state policies as they relate to the transportation of wheelchair-seated students in school buses. Inclusion of best practices in specially equipped school bus and driver training policies was assessed. Key points of interest within state policies were identified based on site visits, common…

School Bus Crash Rates on Routine and Nonroutine Routes

ERIC Educational Resources Information Center

O'Neal, Elizabeth; Ramirez, Marizen; Hamann, Cara; Young, Tracy; Stahlhut, Mary; Peek-Asa, Corinne

2014-01-01

Background: Although prior research has established that school buses are a safe form of transportation, crashes can produce catastrophic consequences. School buses have 2 types of routes: predictable, routine routes that take children to and from school and less predictable, nonroutine routes for school events. No studies have examined school bus…

78 FR 719 - California State Motor Vehicle Pollution Control Standards; Urban Buses; Request for Waiver of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-04

.... Collectively, the five rulemakings elevated the stringency of exhaust emission standards and test procedures... Act for the emission standards and related test procedures contained in its urban bus regulations, as... Standards; Urban Buses; Request for Waiver of Preemption; Opportunity for Public Hearing and Comment AGENCY...

75 FR 16007 - Drawbridge Operation Regulation; Lower Grand River, Iberville Parish, LA

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-31

... minutes to the end of the morning scheduled closure period to provide more time for school buses to... scheduled closure period to provide more time for school buses to transit across the bridge. Extra time is... 75 pontoon bridge, mile 38.4, in Iberville Parish, Louisiana. The Iberville Parish School Board...

New Britain, Conn. School District will Benefit from $125,000 EPA Rebate for Clean Emission School Buses

EPA Pesticide Factsheets

The New Britain, Conn. school district will benefit from a $125,000 US EPA rebate that will pay for retrofitted engines on seven older school buses so they would emit fewer pollutants that are linked to health problems such as asthma and lung damage.

Alternative Fuels Data Center: Pennsylvania Transportation Data for

Science.gov Websites

/TTIwZrpNGf4 Video thumbnail for Pennsylvania School Buses Run on Natural Gas Pennsylvania School Buses Run on Network, Clean School Bus/Vehicle Incentive, and Green Jobs Outreach Program Independence National Partnership for Promoting Natural Gas Vehicles Ready to Roll! - Southeastern Pennsylvania's Regional Electric

Alternative Fuels Data Center

Science.gov Websites

, certain buses, or commercial vehicles that are powered by an alternative fuel, if the vehicles obtain an (GVW) Type of Vehicle Decal Fee 18,000 pounds (lbs.) or less Passenger, School Bus, or Commercial $75 vehicles, buses, or commercial motor vehicles that are powered by compressed natural gas (CNG), liquefied

Busing in Boston: Political Issues. Comparing Political Experiences, Experimental Edition.

ERIC Educational Resources Information Center

Gillespie, Judith A.; Lazarus, Stuart

Unit two to the second-semester "Comparing Political Experiences" course focuses on a specific controversial political issue: court-ordered busing in Boston. A documentary approach represents the core of instruction in this 12th-grade unit. This approach avoids lengthy narratives of a theoretical approach and yet is more in-depth than…

45 CFR 1310.12 - Required use of School Buses or Allowable Alternate Vehicles.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 4 2010-10-01 2010-10-01 false Required use of School Buses or Allowable Alternate Vehicles. 1310.12 Section 1310.12 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR...

45 CFR 1310.12 - Required use of School Buses or Allowable Alternate Vehicles.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 4 2011-10-01 2011-10-01 false Required use of School Buses or Allowable Alternate Vehicles. 1310.12 Section 1310.12 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR...

Alternative Fuels Data Center: Michigan Transportation Data for Alternative

Science.gov Websites

Renewable Energy Laboratory Case Studies Video thumbnail for Michigan's National Lakeshore Reduces Vehicle , 2016 Video thumbnail for Michigan School Buses Get Rolling on Propane Michigan School Buses Get Rolling Videos Text Version More Michigan Videos on YouTube Video thumbnail for Michigan Transports Students in

Alternative Fuels Data Center: Arkansas Launches Natural Gas-Powered Buses

Science.gov Websites

and Refueling StationA> Arkansas Launches Natural Gas-Powered Buses and Refueling Station to a great opportunity for [Rock Region METRO] to continue to meet the needs of our customers with the Cities Coalition (ACCC). Before RRM's board of directors would approve the CNG transition project, they

49 CFR 661.12 - Certification requirement for procurement of buses, other rolling stock and associated equipment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... AMERICA REQUIREMENTS § 661.12 Certification requirement for procurement of buses, other rolling stock and.... Certificate of Compliance with Buy America Rolling Stock Requirements The bidder or offeror hereby certifies... CFR 661.11. Date Signature Company Name Title Certificate of Non-Compliance with Buy America Rolling...

49 CFR 661.12 - Certification requirement for procurement of buses, other rolling stock and associated equipment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... AMERICA REQUIREMENTS § 661.12 Certification requirement for procurement of buses, other rolling stock and.... Certificate of Compliance with Buy America Rolling Stock Requirements The bidder or offeror hereby certifies... CFR 661.11. Date Signature Company Name Title Certificate of Non-Compliance with Buy America Rolling...

49 CFR 661.12 - Certification requirement for procurement of buses, other rolling stock and associated equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... AMERICA REQUIREMENTS § 661.12 Certification requirement for procurement of buses, other rolling stock and.... Certificate of Compliance with Buy America Rolling Stock Requirements The bidder or offeror hereby certifies... CFR 661.11. Date Signature Company Name Title Certificate of Non-Compliance with Buy America Rolling...

49 CFR 661.12 - Certification requirement for procurement of buses, other rolling stock and associated equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... AMERICA REQUIREMENTS § 661.12 Certification requirement for procurement of buses, other rolling stock and.... Certificate of Compliance with Buy America Rolling Stock Requirements The bidder or offeror hereby certifies... CFR 661.11. Date Signature Company Name Title Certificate of Non-Compliance with Buy America Rolling...

COMPARISON OF PARALLEL AND SERIES HYBRID POWERTRAINS FOR TRANSIT BUS APPLICATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Zhiming; Daw, C Stuart; Smith, David E

2016-01-01

The fuel economy and emissions of both conventional and hybrid buses equipped with emissions aftertreatment were evaluated via computational simulation for six representative city bus drive cycles. Both series and parallel configurations for the hybrid case were studied. The simulation results indicate that series hybrid buses have the greatest overall advantage in fuel economy. The series and parallel hybrid buses were predicted to produce similar CO and HC tailpipe emissions but were also predicted to have reduced NOx tailpipe emissions compared to the conventional bus in higher speed cycles. For the New York bus cycle (NYBC), which has the lowestmore » average speed among the cycles evaluated, the series bus tailpipe emissions were somewhat higher than they were for the conventional bus, while the parallel hybrid bus had significantly lower tailpipe emissions. All three bus powertrains were found to require periodic active DPF regeneration to maintain PM control. Plug-in operation of series hybrid buses appears to offer significant fuel economy benefits and is easily employed due to the relatively large battery capacity that is typical of the series hybrid configuration.« less

Variability of particle number emissions from diesel and hybrid diesel-electric buses in real driving conditions.

PubMed

Sonntag, Darrell B; Gao, H Oliver; Holmén, Britt A

2008-08-01

A linear mixed model was developed to quantify the variability of particle number emissions from transit buses tested in real-world driving conditions. Two conventional diesel buses and two hybrid diesel-electric buses were tested throughout 2004 under different aftertreatments, fuels, drivers, and bus routes. The mixed model controlled the confounding influence of factors inherent to on-board testing. Statistical tests showed that particle number emissions varied significantly according to the after treatment, bus route, driver, bus type, and daily temperature, with only minor variability attributable to differences between fuel types. The daily setup and operation of the sampling equipment (electrical low pressure impactor) and mini-dilution system contributed to 30-84% of the total random variability of particle measurements among tests with diesel oxidation catalysts. By controlling for the sampling day variability, the model better defined the differences in particle emissions among bus routes. In contrast, the low particle number emissions measured with diesel particle filters (decreased by over 99%) did not vary according to operating conditions or bus type but did vary substantially with ambient temperature.

Performance evaluation of Platform Data ManagementSystem under various degrees of protocol implementation

NASA Technical Reports Server (NTRS)

Arozullah, Mohammed

1991-01-01

The Platform Data Management System (DMS) collects Housekeeping (H/K), Payload (P/L) Engineering, and Payload Science data from various subsystems and payloads on the platform for transmission to the ground through the downlink via TDRSS. The DMS also distributes command data received from the ground to various subsystems and payloads. In addition, DMS distributes timing and safemode data. The function of collection and distribution of various types of data is performed by the Command and Data Handling (C&DH) subsystem of DMS. The C&DH subsystem uses for this purpose a number of data buses namely, Housekeeping, Payload Engineering, Payload Science, and Time and Safemode buses. Out of these buses, the H/K, P/L Engineering, and P/L Science buses are planned to be implemented by using MIL-STD 1553 bus. Most of the period covered was spent in developing a queue theoretic model of the 1553 Bus as used in the DMS. The aim is to use this model to test the performance and suitability of the 1553 Bus to the DMS under a number of alternative design scenarios.

Characteristics of carbonyl compounds in public vehicles of Beijing city: Concentrations, sources, and personal exposures

NASA Astrophysics Data System (ADS)

Pang, Xiaobing; Mu, Yujing

The characteristics of carbonyl compounds (carbonyls) including concentrations, major sources, and personal exposure were investigated for 29 vehicles including taxi, bus and subway in Beijing. It was found that the taxis (Xiali, TA) and buses (Huanghe, BA) fueled by gasoline with longer service years had the higher indoor carbonyl levels (178±42.7 and 188±31.6 μg m -3) while subways energized by electricity without exhaust and the jingwa buses (BB) driven in the suburb had the lower levels with total concentrations of 98.5±26.3 and 92.1±20.3 μg m -3, respectively. Outdoor carbonyls of taxi cars and buses were nearly at the same level with their total concentrations varying from 80 to 110 μg m -3. The level of outdoor subways carbonyls was equal with the ambient air levels. Exhaust leakage, indoor material emissions, photochemical formation, and infiltration of outdoor air were considered to be the major sources to in-vehicle carbonyls. Personal exposures and cancer risk to formaldehyde and acetaldehyde were calculated for professional bus and taxi drivers, respectively. Taxi drivers had the highest cancer risk with personal exposure to formaldehyde and acetaldehyde of 212 and 243 μg day -1, respectively. The public concern should pay considerable attention to professional drivers' health.

77 FR 17363 - Proposed Establishment of Class E Airspace; West Memphis, AR

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-26

...-0155; Airspace Docket No. 12-ASW-1] Proposed Establishment of Class E Airspace; West Memphis, AR AGENCY... action proposes to establish Class E airspace at West Memphis, AR. Separation of existing Class E... surface at West Memphis, AR, to accommodate the separation of existing Class E airspace surrounding West...

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children’s exposure

PubMed Central

Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

2015-01-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m−3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors). PMID:25904818

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure

NASA Astrophysics Data System (ADS)

Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

2011-03-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 μg m-3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure.

PubMed

Hochstetler, Heather A; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H; Grinshpun, Sergey A

2011-03-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m -3 . The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

Emergency and Disaster Preparedness of School Transportation Staff and School Buses in the United States: Compliance With Recommendations for School Transportation Safety.

PubMed

Olympia, Robert P; Weber, Christopher; Brady, Jodi; Ho, Susana

2017-11-01

The aim of the study was to determine the compliance of school transportation staff and school buses with recommendations for the safe transportation of children to and from school and school-related activities. An electronic questionnaire was distributed to school transportation staff represented by the International Brotherhood of Teamsters during the 2013-2014 academic year. Analysis was performed on 558 completed questionnaires (13% usable response rate). Responders had previous training in first aid (89%), basic life support (28%), and cardiopulmonary resuscitation (52%). Seventy-eight percent of school buses in our sample had restraint devices and 87% had seat belt cutters. Responders reported the immediate availability of the following on their bus: communication devices (81%), first aid kits (97%), fire extinguishers (89%), automated external defibrillators (1%), and epinephrine autoinjectors (2%). Thirty percent of responders have had no previous training in the management of emergencies such as trouble breathing, severe allergic reaction, seizures, cardiac arrest or unresponsiveness, and head, neck, or extremity trauma. Thirteen percent of responders are unfamiliar with or have had no previous training on protocols regarding emergency shelters and community evacuation plans in the event of a disaster. Variability exists in the compliance of school transportation staff and school buses with recommendations for the safe transportation of children. Areas for improvement were identified, such as educating school transportation staff in the recognition and initial management of pediatric emergencies, ensuring the presence of restraint devices, increasing the immediate availability of certain emergency medications and equipment, and familiarizing school transportation staff with designated emergency shelters and community evacuation plans.

49 CFR 665.1 - Purpose.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Federal Transit Act for the purchase or lease of buses with funds obligated by the FTA shall certify to the FTA that any new bus model acquired with such assistance has been tested in accordance with this...

Thermal Insulation

NASA Technical Reports Server (NTRS)

1984-01-01

Commercially known as Solimide, Temptronics, Inc.'s thermal insulation has application in such vehicles as aircraft, spacecraft and surface transportation systems (i.e. rapid transit cars, trains, buses, and ships) as acoustical treatment for door, wall, and ceiling panels, as a means of reducing vibrations, and as thermal insulation (also useful in industrial equipment). Product originated from research conducted by Johnson Space Center on advanced flame-resistant materials for minimizing fire hazard in the Shuttle and other flight vehicles.

49 CFR 571.111 - Standard No. 111; Rearview mirrors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... applies to passenger cars, multipurpose passenger vehicles, trucks, buses, schoolbuses and motorcycles. S4... magnification is considered a unit magnification mirror. S5. Requirements for passenger cars. S5.1Inside rearview mirror. Each passenger car shall have an inside rearview mirror of unit magnification. S5.1.1Field...

49 CFR 571.111 - Standard No. 111; Rearview mirrors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... applies to passenger cars, multipurpose passenger vehicles, trucks, buses, schoolbuses and motorcycles. S4... magnification is considered a unit magnification mirror. S5. Requirements for passenger cars. S5.1Inside rearview mirror. Each passenger car shall have an inside rearview mirror of unit magnification. S5.1.1Field...

Indirect Tire Monitoring System - Machine Learning Approach

NASA Astrophysics Data System (ADS)

Svensson, O.; Thelin, S.; Byttner, S.; Fan, Y.

2017-10-01

The heavy vehicle industry has today no requirement to provide a tire pressure monitoring system by law. This has created issues surrounding unknown tire pressure and thread depth during active service. There is also no standardization for these kind of systems which means that different manufacturers and third party solutions work after their own principles and it can be hard to know what works for a given vehicle type. The objective is to create an indirect tire monitoring system that can generalize a method that detect both incorrect tire pressure and thread depth for different type of vehicles within a fleet without the need for additional physical sensors or vehicle specific parameters. The existing sensors that are connected communicate through CAN and are interpreted by the Drivec Bridge hardware that exist in the fleet. By using supervised machine learning a classifier was created for each axle where the main focus was the front axle which had the most issues. The classifier will classify the vehicles tires condition and will be implemented in Drivecs cloud service where it will receive its data. The resulting classifier is a random forest implemented in Python. The result from the front axle with a data set consisting of 9767 samples of buses with correct tire condition and 1909 samples of buses with incorrect tire condition it has an accuracy of 90.54% (0.96%). The data sets are created from 34 unique measurements from buses between January and May 2017. This classifier has been exported and is used inside a Node.js module created for Drivecs cloud service which is the result of the whole implementation. The developed solution is called Indirect Tire Monitoring System (ITMS) and is seen as a process. This process will predict bad classes in the cloud which will lead to warnings. The warnings are defined as incidents. They contain only the information needed and the bandwidth of the incidents are also controlled so incidents are created within an acceptable range over a period of time. These incidents will be notified through the cloud for the operator to analyze for upcoming maintenance decisions.

Managing Student Behavior on the School Bus: A Key to Bus Safety

ERIC Educational Resources Information Center

American Federation of Teachers (NJ), 2007

2007-01-01

School buses are the safest form of mass transit in America. Every day, school buses travel through congested city traffic and on isolated country roads in all types of weather, safely transporting millions of children to and from school and school-related activities. Federal and state standards for school bus construction and maintenance and…

Helping Black and Latino Males Succeed

ERIC Educational Resources Information Center

Jackson, Robert

2016-01-01

Growing up in a poor, dysfunctional family in a violent inner-city neighborhood, Jackson faced daily challenges even getting to the bus stop without being attacked by gang members. When he was bused to a white suburban school in 5th grade, things got even worse. Every black student who was bused in from his neighborhood was placed in remedial…

A Status report to the Superintendent of Public Instruction on a study of optimal school bus speed limits on Virginia highways.

DOT National Transportation Integrated Search

1988-01-01

The study was prompted by the fact that on Virginia's rural interstate highways there is a three-tiered speed limit: 45 mph for school buses, 55 mph for other buses and trucks, and 65 mph for passenger vehicles. On the urban interstate system, school...

Stopping for School Buses. Traffic Laws Commentary Series.

ERIC Educational Resources Information Center

Yaw, E. Eugene

The degree of uniformity among State laws requiring drivers to stop for school buses receiving or discharging children is not such that drivers could reasonably be expected to know these laws. Because of the wide variation of State laws and the inherent vulnerability of school children and of any vehicle stopping on a highway, there can be no…

No Breathing in the Aisles: Diesel Exhaust inside School Buses.

ERIC Educational Resources Information Center

Solomon, Gina M.; Campbell, Todd R.; Feuer, Gail Ruderman; Masters, Julie; Samkian, Artineh; Paul, Kavita Ann

There is evidence that diesel exhaust causes cancer and premature death, and also exacerbates asthma and other respiratory illness. Noting that the vast majority of the nation's school buses run on diesel fuel, this report details a study examining the level of diesel exhaust to which children are typically exposed as they travel to and from…

49 CFR Appendix A to Part 605 - Appendix A to Part 605

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF TRANSPORTATION SCHOOL BUS OPERATIONS Pt. 605, App. A Appendix A to Part 605 Comptroller General... the City originally included in its grant application a request for funds to purchase 8 buses designed... answered in the order presented. Number one: “The grant of funds to a City to purchase buses and equipment...

49 CFR Appendix A to Part 605 - Appendix A to Part 605

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF TRANSPORTATION SCHOOL BUS OPERATIONS Pt. 605, App. A Appendix A to Part 605 Comptroller General... the City originally included in its grant application a request for funds to purchase 8 buses designed... answered in the order presented. Number one: “The grant of funds to a City to purchase buses and equipment...

Alternative Fuels Data Center: Golden Eagle Delivers Beer With Natural Gas

Science.gov Websites

charging stations. Rental Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Charging Stations Spread Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug-In Electric Bus

Alternative Fuels Data Center: Fisher Coachworks Develops Plug-In Electric

Science.gov Websites

vehicle charging stations. Rental Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles With Natural Gas Oct Electric Buses Aug. 21, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Texas

Science Teacher Training Programme in Rural Schools: An ODL Lesson from Zimbabwe

ERIC Educational Resources Information Center

Mhishi, Misheck; Bhukuvhani, Crispen Erinos; Sana, Abel Farikai

2012-01-01

This case study looked at 76 randomly selected preservice science teachers from Mbire and Guruve districts who were learning at the Mushumbi Centre in Zimbabwe and assessed their motivations for enrolling under the Bindura University of Science Education (BUSE)'s Virtual and Open Distance Learning (VODL) programme. It also looked at the challenges…

The Busing Game. Working Paper Series, W2-30.

ERIC Educational Resources Information Center

Goodman, Allen C.

This monograph provides a format for teaching about busing, either to prospective teachers or to students, on all levels of the educational process. A model is developed that can be used by students themselves in the development of methods of improving human relations and studying problems of democracy and American life. The model presented here…

Chicopee, Mass. School District will Benefit from $200,000 EPA Rebate to Clean Up Emissions from School Buses

EPA Pesticide Factsheets

A school district in Chicopee., Mass. will benefit from $200,000 from the US EPA that will pay for rebates to retrofit the engines on 10 older school buses so they would emit fewer pollutants that are linked to health problems such as asthma & lung damage.

Improving School Bus Safety. Transportation Research Board Special Report 222.

ERIC Educational Resources Information Center

National Academy of Sciences - National Research Council, Washington, DC. Transportation Research Board.

While school buses transport more passengers per trip, the rate of occupant fatalities per mile driven for school buses is one-quarter that for passenger cars. Nevertheless, the public expects school districts and other school bus operators to take all reasonable precautions to protect children as they travel to and from school. Although a variety…

76 FR 53102 - Federal Motor Vehicle Safety Standards; Denial of Petition for Rulemaking; School Buses

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-25

... chronological order): Studies NTSB, 1987 In 1987, the NTSB reported on its investigation of forty-three post... seat belts by using the sled test data obtained from NHTSA's 2002 school bus safety study. For... incorporate test procedures to test lap/shoulder belts in small school buses and voluntarily-installed lap...

How to Cut Costs by Saving School Bus Fuel.

ERIC Educational Resources Information Center

Seiff, Hank

A program started in Washington County, Maryland in 1980 has been successful in saving school bus fuel and bringing down transportation costs incurred by its fleet of 200 buses. Driver training and motivation, as well as a partial transfer to diesel buses, are at the heart of the program. The drivers are taught five fuel saving techniques: cut…

Walking School Buses as a Form of Active Transportation for Children--A Review of the Evidence

ERIC Educational Resources Information Center

Smith, Liz; Norgate, Sarah H.; Cherrett, Tom; Davies, Nigel; Winstanley, Christopher; Harding, Mike

2015-01-01

Background: Walking school buses (WSBs) offer a potentially healthier way for children to get to school while reducing traffic congestion. A number of pressing societal challenges make it timely to evaluate evidence of their value. Methods: Studies that focused solely on WSBs were identified through online and manual literature searches. Twelve…

Alternative Fuels for Washington's School Buses: A Report to the Washington State Legislature.

ERIC Educational Resources Information Center

Lyons, John Kim; McCoy, Gilbert A.

This document presents findings of a study that evaluated the use of both propane and compressed natural gas as alternative fuels for Washington State school buses. It discusses air quality improvement actions by state- and federal-level regulators and summarizes vehicle design, development, and commercialization activities by all major engine,…

45 CFR 1310.12 - Required use of School Buses or Allowable Alternate Vehicles.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 4 2013-10-01 2013-10-01 false Required use of School Buses or Allowable Alternate Vehicles. 1310.12 Section 1310.12 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

45 CFR 1310.12 - Required use of School Buses or Allowable Alternate Vehicles.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 4 2012-10-01 2012-10-01 false Required use of School Buses or Allowable Alternate Vehicles. 1310.12 Section 1310.12 Public Welfare Regulations Relating to Public Welfare (Continued) OFFICE OF HUMAN DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND FAMILIES, HEAD START...

Foothill Transit Electric Bus Testing | Transportation Research | NREL

Science.gov Websites

, this study aims to improve understanding of the overall usage and effectiveness of fast-charge electric well. The electric buses under study were Proterra EcoRide BE35 transit buses with eight 368V lithium Systems Technology Simulator, or FASTSim, to study the impact of route selection and other vehicle

Health risk represented by inhaling polycyclic aromatic hydrocarbons (PAH) during daily commuting involving using a high traffic flow route in Bogotá.

PubMed

Pachón, Jorge E; Sarmiento, Hugo; Hoshiko, Tomomi

2013-01-01

Assessing the risk to health by inhaling particles and particle-bound PAH during daily commuting along a high traffic flow route/corridor in Bogotá. A van was equipped with a PAS2000 photo-electric sensor for real-time measurement of particle-bound PAH and a Dust Trakfor monitoring PM10 concentration; it drove along typical commuting routes in the city. Exposure to particles and particle-bound PAH was assessed by using an inhalation intake model. A similar trend was observed for both PM10 and PAH concentration, indicating that traffic was the same source for both contaminants. Extreme PM10 and PAH inhalation concentrations were recorded every time direct bus and microbus emissions were measured by the van. Inhalation model results indicated that exposure was significantly greater when using a venues having mixed traffic use (i.e. buses, microbuses, passenger vehicles, motorcycles) compared to using roads where the TransMilenio system (articulated buses) had been implemented. The results may support evaluating bus drivers, commuters and bike users' exposure to toxic compounds in the city.

Fly-by-Light Advanced Systems Hardware (FLASH) program

NASA Astrophysics Data System (ADS)

Bedoya, Carlos A.

1995-05-01

Fiber optics are immune to electromagnetic emissions and have the potential to eliminate this concern especially in flight critical applications if they can be developed to the same level of technology as current systems using wire to carry the signals. As aircraft become more and more dependent of digital signals to control all systems, the Electromagnetic Environment (EME) will become more and more a concern for the safe long term operation. The International Severe HIRF electromagnetic environment (EME) is less than 2000 Volts per meter below 400 MHz and reaches a maximum of 6,850 Volts per meter in the 4-6 GHz range. The normal assumption is that a metal or composite aircraft skin with appropriate seals provides 20 dB attenuation of the external environment. This reduces peak levels at the avionics boxes to less than 200 Volts per meter below 400 MHz and a maximum of 685 Volts per meter in the 406 GHz range. MIL-STD-461D imposed an additional box level requirement to 200 Volts per meter from 10 KHz to 40 GHz. This requirement equals or surpasses the attenuated HIRF environment over significant portions of the spectrum and implies that the aircraft must be designed to achieve and maintain this value throughout its service life. Although wires can be shielded and designed to achieve these requirements, it is a more expensive process, adds the weight of shielding and requires maintenance of the shielding integrity at all times. The very light weight and high bandwidth of fiber optics also offer the potential of eliminating the number of connections and weight savings in aircraft. For example on a one to one replacement of wire by fiber, it is estimated that fiber would weight about 1/20 the weight of wire. Current wire buses used for duplex communications in aircraft applications have a bandwidth of about 1 MHz while equivalent buses using fiber optics have a bandwidth of 20 MHz. For other applications such as video and avionics interfaces, fiber buses in the hundreds of MHz are available. Applications of fiber optic buses would then result in the reduction of wires and connections because of reduction in the number of buses needed for information transfer due to the fact that a large number of different signals can be sent across one fiber by multiplexing each signal. The Advanced Research Projects Agency (ARPA) Technology Reinvestment Project (TRP) Fly-by-Light Advanced Systems Hardware (FLASH) program addresses the development of Fly-by-Light Technology in order to apply the benefits of fiber optics to military and commercial aircraft.

49 CFR 571.113 - Standard No. 113; Hood latch system.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...

49 CFR 571.113 - Standard No. 113; Hood latch system.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...

49 CFR 571.113 - Standard No. 113; Hood latch system.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...

49 CFR 571.113 - Standard No. 113; Hood latch system.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...

49 CFR 571.113 - Standard No. 113; Hood latch system.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... Application. This standard applies to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3... engine, luggage, storage, or battery compartment. S4. Requirements. S4.1Each hood must be provided with a...

49 CFR 37.199 - [Reserved

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false [Reserved] 37.199 Section 37.199 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.199 [Reserved] ...

On-road, in-use gaseous emission measurements by remote sensing of school buses equipped with diesel oxidation catalysts and diesel particulate filters.

PubMed

Burgard, Daniel A; Provinsal, Melissa N

2009-12-01

A remote sensing device was used to obtain on-road and in-use gaseous emission measurements from three fleets of schools buses at two locations in Washington State. This paper reports each fleet's carbon monoxide (CO), hydrocarbon (HC), nitric oxide (NO), and nitrogen dioxide (NO2) mean data. The fleets represent current emission retrofit technologies, such as diesel particulate filters and diesel oxidation catalysts, and a control fleet. This study shows that CO and HC emissions decrease with the use of either retrofit technology when compared with control buses of the same initial emission standards. The CO and HC emission reductions are consistent with published U.S. Environmental Protection Agency verified values. The total oxides of nitrogen (NOx), NO, and the NO2/NOx ratio all increase with each retrofit technology when compared with control buses. As was expected, the diesel particulate filters emitted significantly higher levels of NO2 than the control fleet because of the intentional conversion of NO to NO2 by these systems. Most prior research suggests that NOx emissions are unaffected by the retrofits; however, these previous studies have not included measurements from retrofit devices on-road and after nearly 5 yr of use. Two 2006 model-year buses were also measured. These vehicles did not have retrofit devices but were built to more stringent new engine standards. Reductions in HCs and NOx were observed for these 2006 vehicles in comparison to other non-retrofit earlier model-year vehicles.

Estimating the contributions of mobile sources of PAH to urban air using real-time PAH monitoring.

PubMed

Dunbar, J C; Lin, C I; Vergucht, I; Wong, J; Duran, J L

2001-11-12

Motor vehicles are a significant source of airborne polycyclic aromatic hydrocarbons (PAH) in many urban areas. Traditional approaches used in determining the relative contributions of individual vehicle types to the total amount of PAH in air have been based on the analysis of integrated samples of airborne particles and gases for the presence of chemical tracers indicative of the vehicles from which the chemicals derived. As an alternative, we have used a photoelectric aerosol sensor (PAS) capable of measuring PAH levels in real-time in the emissions plumes from motor vehicles. We placed the PAS near a traffic-light in Kenmore Square, a busy crossroads in downtown Boston (MA, USA). A video camera co-located at the site recorded the vehicles passing the sensor, and this record was correlated with the PAS data. During a 5-day monitoring period (approximately 59 h) in the summer of 1998, over 34,000 motor vehicles were counted and classified and over 24,000 PAS readings were recorded (frequency = 1/8.6 s). The composition of the vehicle population was 94% passenger vehicles, 1.4% buses, 2.6% small trucks, 1.3% medium trucks, 0.35% large trucks, and 0.45% garbage and construction trucks. In analyzing the PAS data, it was assumed that the highest PAS measurements--those that exceeded the 95% critical level of the 5-min moving average of all the PAS measurements--were indicative of primary vehicular emissions. We found that approximately 46% of the mass of particle-bound PAH (i.e. approximately 46% of the integrated area under the PAS signal vs. time plots) was attributable to primary emissions from motor vehicles passing the sensor. Of this, 35-61% was attributable to passenger vehicles (cars, pickup trucks, and sports utility vehicles) and 39-65% was attributable to non-passenger vehicles [buses (14-23%), small trucks (12-20%), medium trucks (8.4-14%), large trucks (2.9-4.8%) and garbage and construction trucks (1.9-3.2%)]. Our results suggest that on a per vehicle basis, buses and trucks--the majority of which run on diesel fuel--emitted greater amounts of particle-bound PAH than passenger vehicles. Overall, we found that real-time photoelectric aerosol sensing (in combination with video photography) is useful for estimating the contributions of airborne PAB from different vehicle types. Due to the physical constraints of our monitoring site and the high volumes of traffic, however, it was not possible to uniquely attribute PAS signals to individual vehicles.

Transportation of Children: Ensuring Occupant Safety

ERIC Educational Resources Information Center

Craft, Nick

2004-01-01

The two riskiest things to do with children is open the door to the playground and open the door to buses and vans. Experience proves that when serious injuries occur, they will happen in one of these two places. While the great debate over the safety of buses versus vans has now been settled, the issue regarding occupant safety is on fire in most…

Alternative Fuels Data Center: Cleveland Car Dealership Working Toward a

Science.gov Websites

charging stations. Rental Cars Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Stations Spread Through Philly March 3, 2012 Natural Gas School Buses Help Kansas City Save Money Nov. 12 Natural Gas Street Sweepers Improve Air Quality in New York March 11, 2010 Propane Buses Save Money for

Alternative Fuels Data Center: Kansas City Kansas Public Schools Invests in

Science.gov Websites

station for up to 70 CNG school buses, one mobile CNG refueling unit, and CNG safety modifications to the buses and fast-fill dispensers for public access. After receiving only one response, KCKPS simplified , or at one of the City of Kansas City, Missouri's private fast-fill stations. The first CNG bus was

An Unfulfilled Dream: A Catalogue and Analysis of the Differing Perceptions of Busing 1954-1976.

ERIC Educational Resources Information Center

Hennessey, Gary J.

During the period 1954 to 1976, the public's perception and ultimate reaction to busing went from mild disfavor to vehement rejection. An analysis of the information which seemed to cause this revealed that four factors seemed to be involved: the neighborhood school concept and its validity; the educational benefit to be derived from the program;…

Alternative Fuels Data Center: Propane Buses Help Minnesota Schools Carve

Science.gov Websites

information about this project, contact Twin Cities Clean Cities Coalition. Download QuickTime Video QuickTime videos provided by Clean Cities TV and FuelEconomy.gov. MotorWeek - Television's Original Automotive Propane Aug. 22, 2015 A photo of two national parks buses parked in front of Redwood trees. Clean Cities

Special Study: Inadequate Structural Assembly of Schoolbus Bodies. The Accidents at Decatur and Huntsville, Alabama.

ERIC Educational Resources Information Center

National Transportation Safety Board (DOT), Washington, DC. Bureau of Surface Transportation Safety.

This study reviews some examples of injuries received in two school bus accidents; explains how the design of joints and fastenings in the buses was involved in the injuries and in the structural strength of schoolbuses; and compares schoolbus construction with construction of other types of buses that employ more efficient and complete…

Comparison of Parallel and Series Hybrid Power Trains for Transit Bus Applications

DOE PAGES

Gao, Zhiming; Daw, C. Stuart; Smith, David E.; ...

2016-08-01

The fuel economy and emissions of conventional and hybrid buses equipped with emissions after treatment were evaluated via computational simulation for six representative city bus drive cycles. Both series and parallel configurations for the hybrid case were studied. The simulation results indicated that series hybrid buses have the greatest overall advantage in fuel economy. The series and parallel hybrid buses were predicted to produce similar carbon monoxide and hydrocarbon tailpipe emissions but were also predicted to have reduced tailpipe emissions of nitrogen oxides compared with the conventional bus in higher speed cycles. For the New York bus cycle, which hasmore » the lowest average speed among the cycles evaluated, the series bus tailpipe emissions were somewhat higher than they were for the conventional bus; the parallel hybrid bus had significantly lower tailpipe emissions. All three bus power trains were found to require periodic active diesel particulate filter regeneration to maintain control of particulate matter. Finally, plug-in operation of series hybrid buses appears to offer significant fuel economy benefits and is easily employed because of the relatively large battery capacity that is typical of the series hybrid configuration.« less

Biodiesel from waste cooking oil in Mexico City.

PubMed

Sheinbaum, Claudia; Balam, Marco V; Robles, Guillermo; Lelo de Larrea, Sebastian; Mendoza, Roberto

2015-08-01

The aim of this article is to evaluate the potential use of biodiesel produced from waste cooking oil in Mexico City. The study is divided in two main areas: the analysis of a waste cooking oil collection pilot project conducted in food markets of a Mexico City region; and the exhaust emissions performance of biodiesel blends measured in buses of the Mexico City public bus transportation network (RTP). Results from the waste cooking oil collection pilot project show that oil quantities disposed depend upon the type of food served and the operational practices in a cuisine establishment. Food markets' waste cooking oil disposal rate from fresh oil is around 10%, but with a very high standard deviation. Emission tests were conducted using the Ride-Along-Vehicle-Emissions-Measuring System in two different types of buses while travelling a regular route. Results shows that the use of biodiesel blends reduces emissions only for buses that have exhaust gas recirculation systems, as analysed by repeated measure analysis of variance. The potential use in Mexico City of waste cooking oil for biodiesel is estimated to cover 2175 buses using a B10 blend. © The Author(s) 2015.

Comparison of Parallel and Series Hybrid Power Trains for Transit Bus Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Zhiming; Daw, C. Stuart; Smith, David E.

The fuel economy and emissions of conventional and hybrid buses equipped with emissions after treatment were evaluated via computational simulation for six representative city bus drive cycles. Both series and parallel configurations for the hybrid case were studied. The simulation results indicated that series hybrid buses have the greatest overall advantage in fuel economy. The series and parallel hybrid buses were predicted to produce similar carbon monoxide and hydrocarbon tailpipe emissions but were also predicted to have reduced tailpipe emissions of nitrogen oxides compared with the conventional bus in higher speed cycles. For the New York bus cycle, which hasmore » the lowest average speed among the cycles evaluated, the series bus tailpipe emissions were somewhat higher than they were for the conventional bus; the parallel hybrid bus had significantly lower tailpipe emissions. All three bus power trains were found to require periodic active diesel particulate filter regeneration to maintain control of particulate matter. Finally, plug-in operation of series hybrid buses appears to offer significant fuel economy benefits and is easily employed because of the relatively large battery capacity that is typical of the series hybrid configuration.« less

HEAVY-DUTY VEHICLE IN USE EMISSION PERFORMANCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nylund, N; Ikonen, M; Laurikko, J

2003-08-24

Engines for heavy-duty vehicles are emission certified by running engines according to specified load pattern or duty cycle. In the US, the US Heavy-Duty Transient cycle has been in use already for a number of years, and Europe is, according to the requirements of the Directive 1999/96/EC gradually switching to transient-type testing. Evaluating the in-use emission performance of heavy-duty vehicles presents a problem. Taking engines out of vehicles for engine dynamometer testing is difficult and costly. In addition, engine dynamometer testing does not take into account the properties of the vehicle itself (i.e. mass, transmission etc.). It is also debatable,more » how well the standardized duty cycles reflect real-life -driving patterns. VTT Processes has recently commissioned a new emission laboratory for heavy-duty vehicles. The facility comprises both engine test stand and a fully transient heavy-duty chassis dynamometer. The roller diameter of the dynamometer is 2.5 meters. Regulated emissions are measured using a full-flow CVS system. The HD vehicle chassis dynamometer measurements (emissions, fuel consumption) has been granted accreditation by the Centre of Metrology and Accreditation (MIKES, Finland). A national program to generate emission data on buses has been set up for the years 2002-2004. The target is to generate emission factors for some 50 different buses representing different degree of sophistication (Euro 1 to Euro5/EEV, with and without exhaust gas aftertreatment), different fuel technologies (diesel, natural gas) and different ages (the effect of aging). The work is funded by the Metropolitan Council of Helsinki, Helsinki City Transport, The Ministry of Transport and Communications Finland and the gas company Gasum Oy. The International Association for Natural Gas Vehicles (IANGV) has opted to buy into the project. For IANGV, VTT will deliver comprehensive emission data (including particle size distribution and chemical and biological characterization of particles) for up-to-date diesel and natural gas vehicles. The paper describes the methodology used for the measurements on buses, the test matrix and some preliminary emission data on both regulated and unregulated emissions.« less

Voltage Analysis Improvement of 150 kV Transmission Subsystem Using Static Synchronous Compensator (STATCOM)

NASA Astrophysics Data System (ADS)

Akbar, P. A.; Hakim, D. L.; Sucita, T.

2018-02-01

In this research, testing improvements to the distribution voltage electricity at 150 kV transmission subsystem Bandung Selatan and New Ujungberung using Flexible AC Transmission System (FACTS) technology. One of them is by doing the control of active and reactive power through the power electronics equipment Static Synchronous Compensator (STATCOM). The subsystem is tested because it has a voltage profile are relatively less well when based on the IEEE / ANSI C.84.1 (142.5 - 157.5 kV). This study was conducted by analyzing the Newton-Raphson power flow on the simulator DigSilent Power Factory 15 to determine the profile of the voltage (V) on the system. Bus which has the lowest voltage to be a reference in the installation of STATCOM. From this research is known that the voltage on the conditions of the existing bus 28, as many as 21-23 still below standard buses (142.5 kV), after the installation is done using STATCOM, voltage on the buses improved by increasing the number of tracks that follow the standard / is in the range 142.5 kV -157.5 kV as many as 23-27 buses or 78.6% - 96%, with the optimum mounting on a bus Rancaekek STATCOM II with a capacity of 300 MVA.

American Fuel Cell Bus Project Evaluation. Second Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eudy, Leslie; Post, Matthew

2015-09-01

This report presents results of the American Fuel Cell Bus (AFCB) Project, a demonstration of fuel cell electric buses operating in the Coachella Valley area of California. The prototype AFCB was developed as part of the Federal Transit Administration's (FTA's) National Fuel Cell Bus Program. Through the non-profit consortia CALSTART, a team led by SunLine Transit Agency and BAE Systems developed a new fuel cell electric bus for demonstration. SunLine added two more AFCBs to its fleet in 2014 and another in 2015. FTA and the AFCB project team are collaborating with the U.S. Department of Energy (DOE) and DOE'smore » National Renewable Energy Laboratory to evaluate the buses in revenue service. This report summarizes the performance results for the buses through June 2015.« less

Establishment of Class e1 Mass Standard of 50 kg

NASA Astrophysics Data System (ADS)

Yao, Hong; Wang, Jian; Ding, Jingan; Zhong, Ruilin; Ren, Xiaoping

Because of the equipment limit, the dissemination of large mass has been realized by a large amount of higher class of 20 kg weights since 1950s in China. But with improvement of the technique and customer's requirements, it is necessary to establish the mass standard of 50 kg weight. In 1990s, mass standard laboratory has set up Class E1 weight sets from 20 kg to 1 mg. To extend the mass capacity up to 50 kg of Class E1, it is not only to produce Class E1 50 kg weight and import a mass comparator, but also need to lift the heavy weight from weight box to balance receptor safely. Up to now, the mass comparator has been installed in Hepingli campus of NIM. Two pieces of Class E1 50 kg weights are determined by combination weighing method. A lifting device has been mounted close to the mass comparator in order to move the 50 kg easily.

Pocket guide to large truck and bus statistics, 2015.

DOT National Transportation Integrated Search

2015-04-01

The Federal Motor Carrier Safety Administration compiled the data in this guide from multiple sources. The guide is divided into six sections and a glossary: (1) Overview: Large Trucks and Buses, (2) Roadside Inspections and Violations, (3) Reviews, ...

Pocket guide to large trucks and bus statistics, 2014.

DOT National Transportation Integrated Search

2014-10-01

The Federal Motor Carrier Safety Administration compiled the data in this guide from multiple sources. The guide is divided into six sections and a glossary: (1) Overview: Large Trucks and Buses, (2) Roadside Inspections and Violations, (3) Reviews, ...

40 CFR Table E-1 to Subpart E of... - Summary of Test Requirements for Reference and Class I Equivalent Methods for PM2.5 and PM10-2.5

Code of Federal Regulations, 2010 CFR

2010-07-01

... Reference and Class I Equivalent Methods for PM2.5 and PM10-2.5 E Table E-1 to Subpart E of Part 53... MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 Pt. 53...

75 FR 16913 - Transmission Relay Loadability Reliability Standard

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-02

... B. Approval of PRC-023-1 13 C. Applicability 20 D. Generator Step-Up and Auxiliary Transformers......... 98 1. Omission From the Reliability Standard 98 2. Generator Step-Up Transformer Relays as Back-up... series elements such as transformers) that emanates from the remote buses. All transmission owners shall...

Crystal structure of the Streptomyces coelicolor sortase E1 transpeptidase provides insight into the binding mode of the novel class E sorting signal

DOE PAGES

Kattke, Michele D.; Chan, Albert H.; Duong, Andrew; ...

2016-12-09

Here, many species of Gram-positive bacteria use sortase transpeptidases to covalently affix proteins to their cell wall or to assemble pili. Sortase-displayed proteins perform critical and diverse functions for cell survival, including cell adhesion, nutrient acquisition, and morphological development, among others. Based on their amino acid sequences, there are at least six types of sortases (class A to F enzymes); however, class E enzymes have not been extensively studied. Class E sortases are used by soil and freshwater-dwelling Actinobacteria to display proteins that contain a non-canonical LAXTG sorting signal, which differs from 90% of known sorting signals by substitution ofmore » alanine for proline. Here we report the first crystal structure of a class E sortase, the 1.93 Å resolution structure of the SrtE1 enzyme from Streptomyces coelicolor. The active site is bound to a tripeptide, providing insight into the mechanism of substrate binding. SrtE1 possesses β3/β4 and β6/β7 active site loops that contact the LAXTG substrate and are structurally distinct from other classes. We propose that SrtE1 and other class E sortases employ a conserved tyrosine residue within their β3/β4 loop to recognize the amide nitrogen of alanine at position P3 of the sorting signal through a hydrogen bond, as seen here. Incapability of hydrogen-bonding with canonical proline-containing sorting signals likely contributes to class E substrate specificity. Furthermore, we demonstrate that surface anchoring of proteins involved in aerial hyphae formation requires an N-terminal segment in SrtE1 that is presumably positioned within the cytoplasm. Combined, our results reveal unique features within class E enzymes that enable them to recognize distinct sorting signals, and could facilitate the development of substrate-based inhibitors of this important enzyme family.« less

Public transportation and tuberculosis transmission in a high incidence setting.

PubMed

Zamudio, Carlos; Krapp, Fiorella; Choi, Howard W; Shah, Lena; Ciampi, Antonio; Gotuzzo, Eduardo; Heymann, Jody; Seas, Carlos; Brewer, Timothy F

2015-01-01

Tuberculosis (TB) transmission may occur with exposure to an infectious contact often in the setting of household environments, but extra-domiciliary transmission also may happen. We evaluated if using buses and/or minibuses as public transportation was associated with acquiring TB in a high incidence urban district in Lima, Peru. Newly diagnosed TB cases with no history of previous treatment and community controls were recruited from August to December 2008 for a case-control study. Crude and adjusted odd ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression to study the association between bus/minibus use and TB risk. One hundred forty TB cases and 80 controls were included. The overall use of buses/minibuses was 44.9%; 53.3% (72/135) among cases and 30.4% (24/79) among controls [OR: 3.50, (95% CI: 1.60-7.64)]. In the TB group, 25.7% (36/140) of subjects reported having had a recent household TB contact, and 13% (18/139) reported having had a workplace TB contact; corresponding figures for controls were 3.8% (3/80) and 4.1% (3/73), respectively[OR: 8.88 (95% CI: 2.64-29.92), and OR: 3.89 (95% CI: 1.10-13.70)]. In multivariate analyses, age, household income, household contact and using buses/minibuses to commute to work were independently associated with TB [OR for bus/minibus use: 11.8 (95% CI: 1.45-96.07)]. Bus/minibus use to commute to work is associated with TB risk in this high-incidence, urban population in Lima, Peru. Measures should be implemented to prevent TB transmission through this exposure.

76 FR 39259 - Establishment of Class E Airspace; Brunswick, ME

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

...-0116; Airspace Docket No. 11-ANE-1] Establishment of Class E Airspace; Brunswick, ME AGENCY: Federal... Class E airspace at Brunswick Executive Airport, Brunswick, ME. DATES: The effective date is moved from... Class E airspace at Brunswick Executive Airport, Brunswick, ME. This action will move up the effective...

77 FR 32896 - Modification of Class E Airspace; Billings, MT

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-04

...-0316; Airspace Docket No. 12-ANM-1] Modification of Class E Airspace; Billings, MT AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action modifies Class E airspace at... were received. Class E airspace designations are published in paragraph 6005, of FAA Order 7400.9V...

Development of a School Bus Fuel System Integrity Compliance Procedure. Final Report.

ERIC Educational Resources Information Center

Morrow, G. W.; Johnson, N. B.

This report presents a program that derived a compliance test procedure for school buses with a gross vehicle weight of 10,000 pounds or greater. The objective of this program was to evaluate Fuel System Integrity (FMVSS 301) in relation to school buses, conduct a limited state-of-the-art survey and run full-scale dynamic tests to produce an…

Alternative Fuels Data Center: Electric Buses Hit the Streets in Kentucky

Science.gov Websites

, Kentucky, diversified its fleet with all-electric buses. For information about this project, contact Photo of a car Electric Vehicles Charge up at State Parks in West Virginia Dec. 9, 2017 Photo of a car Hydrogen Powers Fuel Cell Vehicles in California Nov. 18, 2017 Photo of a car Smart Car Shopping Nov. 4

In-Use Performance Comparison of Hybrid Electric, CNG, and Diesel Buses at New York City Transit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnitt, R. A.

2008-06-01

The National Renewable Energy Laboratory (NREL) evaluated the performance of diesel, compressed natural gas (CNG), and hybrid electric (equipped with BAE Systems? HybriDrive propulsion system) transit buses at New York City Transit (NYCT). CNG, Gen I and Gen II hybrid electric propulsion systems were compared on fuel economy, maintenance and operating costs per mile, and reliability.

Isn't a Safe Bus Worth Another $300 -- And Isn't a Trained Driver Essential?

ERIC Educational Resources Information Center

American School Board Journal, 1973

1973-01-01

Argues that all drivers of school buses should be trained professionals, and explains how parent awareness of discipline problems on buses can be increased by playing them a tape recording of a ride. Discusses the efforts of a research team to draft a performance standard for the construction of a school bus body with emphasis on panel separation,…

Criteria pollutant and greenhouse gas emissions from CNG transit buses equipped with three-way catalysts compared to lean-burn engines and oxidation catalyst technologies.

PubMed

Yoon, Seungju; Collins, John; Thiruvengadam, Arvind; Gautam, Mridul; Herner, Jorn; Ayala, Alberto

2013-08-01

Engine and exhaust control technologies applied to compressed natural gas (CNG) transit buses have advanced from lean-burn, to lean-burn with oxidation catalyst (OxC), to stoichiometric combustion with three-way catalyst (TWC). With this technology advancement, regulated gaseous and particulate matter emissions have been significantly reduced. Two CNG transit buses equipped with stoichiometric combustion engines and TWCs were tested on a chassis dynamometer, and their emissions were measured. Emissions from the stoichiometric engines with TWCs were then compared to the emissions from lean-burn CNG transit buses tested in previous studies. Stoichiometric combustion with TWC was effective in reducing emissions of oxides of nitrogen (NO(x)), particulate matter (PM), and nonmethane hydrocarbon (NMHC) by 87% to 98% depending on pollutants and test cycles, compared to lean combustion. The high removal efficiencies exceeded the emission reduction required from the certification standards, especially for NO(x) and PM. While the certification standards require 95% and 90% reductions for NO(x) and PM, respectively, from the engine model years 1998-2003 to the engine model year 2007, the measured NO(x) and PM emissions show 96% and 95% reductions, respectively, from the lean-burn engines to the stoichiometric engines with TWC over the transient Urban Dynamometer Driving Schedule (UDDS) cycle. One drawback of stoichiometric combustion with TWC is that this technology produces higher carbon monoxide (CO) emissions than lean combustion. In regard to controlling CO emissions, lean combustion with OxC is more effective than stoichiometric combustion. Stoichiometric combustion with TWC produced higher greenhouse gas (GHG) emissions including carbon dioxide (CO2) and methane (CH4) than lean combustion during the UDDS cycle, but lower GHG emissions during the steady-state cruise cycle. Stoichiometric combustion with three-way catalyst is currently the best emission control technology available for compressed natural gas (CNG) transit buses to meet the stringent U.S. Environmental Protection Agency (EPA) 2010 heavy-duty engine NO(x) emissions standard. For existing lean-burn CNG transit buses in the fleet, oxidation catalyst would be the most effective retrofit technology for the control of NMHC and CO emissions.

Influence of large changes in public transportation (Transantiago) on the black carbon pollution near streets

NASA Astrophysics Data System (ADS)

Gramsch, E.; Le Nir, G.; Araya, M.; Rubio, M. A.; Moreno, F.; Oyola, P.

2013-02-01

In 2006 a large transformation was carried out on the public transportation system in Santiago de Chile. The original system (before 2006) had hundreds of bus owners with about 7000 diesel buses. The new system has only 13 firms with about 5900 buses which operate in different parts of the city with little overlap between them. In this work we evaluate the impact of the Transantiago system on the black carbon pollution along four roads directly affected by the modification to the transport system. Measurements were carried out during May-July of 2005 (before Transantiago) and June-July of 2007 (after Transantiago). We have used the Wilcoxon rank-sum test to evaluate black carbon concentration in four streets in year 2005 and 2007. The results show that a statistically significant reduction between year 2005 (before Transantiago) and year 2007 (after Transantiago) in Alameda street, which changed from a mean of 18.8 μg m-3 in 2005 to 11.9 μg m-3 in 2007. In this street there was a decrease in the number of buses as well as the number of private vehicles and an improvement in the technology of public transportation between those years. Other two streets (Usach and Departamental) did not change or experienced a small increase in the black carbon concentration in spite of having less flux of buses in 2007. Eliodoro Yañez Street, which did not have public transportation in 2005 or 2007 experienced a 15% increase in the black carbon concentration between those years. Analysis of the data indicates that the change is related to a decrease in the total number of vehicles or the number of other diesel vehicles in the street rather than a decrease in the number of buses only. These results are an indication that in order to decrease pollution near a street is not enough to reduce the number of buses or improve its quality, but to reduce the total number of vehicles.

Alternative Fuels Data Center: Clean Cities Helps the National Mall Cut

Science.gov Websites

Transit Efficiency March 8, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of a Yellowstone National Park Commits to Alternative Fuels Oct. 16, 2010 Propane Buses Save Money for Virginia

Traffic safety facts 1993 : school buses

DOT National Transportation Integrated Search

1994-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1983, 1,572 people h...

Traffic safety facts 1995 : school buses

DOT National Transportation Integrated Search

1996-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1985, 1,478 people h...

Traffic safety facts 1994 : school buses

DOT National Transportation Integrated Search

1995-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1984, 1,517 people h...

Traffic safety facts 2000 : school buses

DOT National Transportation Integrated Search

2001-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1990, 1,450 people h...

Traffic safety facts 1996 : school buses

DOT National Transportation Integrated Search

1997-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1986, 1,458 people h...

Traffic safety facts 1998 : school buses

DOT National Transportation Integrated Search

1999-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1988, 1,409 people h...

Traffic safety facts 1999 : school buses

DOT National Transportation Integrated Search

2000-01-01

A school bus-related crash is a crash which involves, either directly or indirectly, a school bus-type vehicle, or a vehicle functioning as a school bus, transporting children to or from school or school-related activities. Since 1989, 1,445 people h...

Diesel and CNG Transit Bus Emissions Characterization By Two Chassis Dynamometer Laboratories: Results and Issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nigel N. Clark, Mridul Gautam; Byron L. Rapp; Donald W. Lyons

1999-05-03

Emissions of six 32 passenger transit buses were characterized using one of the West Virginia University (WVU) Transportable Heavy Duty Emissions Testing Laboratories, and the fixed base chassis dynamometer at the Colorado Institute for Fuels and High Altitude Engine Research (CIFHAER). Three of the buses were powered with 1997 ISB 5.9 liter Cummins diesel engines, and three were powered with the 1997 5.9 liter Cummins natural gas (NG) counterpart. The NG engines were LEV certified. Objectives were to contrast the emissions performance of the diesel and NG units, and to compare results from the two laboratories. Both laboratories found thatmore » oxides of nitrogen and particulate matter (PM) emissions were substantially lower for the natural gas buses than for the diesel buses. It was observed that by varying the rapidity of pedal movement during accelerations in the Central Business District cycle (CBD), CO and PM emissions from the diesel buses could be varied by a factor of three or more. The driving styles may be characterized as aggressive and non-aggressive, but both styles followed the CBD speed command acceptably. PM emissions were far higher for the aggressive driving style. For the NG fueled vehicles driving style had a similar, although smaller, effect on NO{sub x}. It is evident that driver habits may cause substantial deviation in emissions for the CBD cycle. When the CO emissions are used as a surrogate for driver aggression, a regression analysis shows that NO{sub x} and PM emissions from the two laboratories agree closely for equivalent driving style. Implications of driver habit for emissions inventories and regulations are briefly considered.« less

75 FR 13453 - Proposed Amendment of Class E Airspace; Corpus Christi, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-22

...-0089; Airspace Docket No. 10-ASW-1] Proposed Amendment of Class E Airspace; Corpus Christi, TX AGENCY... action proposes to amend Class E airspace in the Corpus Christi, TX area. Additional controlled airspace... adding additional Class E airspace extending upward from 700 feet above the surface in the Corpus Christi...

78 FR 57788 - Amendment of Class E Airspace; Everett, WA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-20

...-0434; Airspace Docket No. 13-ANM-1] Amendment of Class E Airspace; Everett, WA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action modifies Class E airspace at Everett, WA, to... the FAA. No comments were received. Class E airspace designations are published in paragraph 6004, of...

77 FR 68067 - Establishment of Class E Airspace; Coaldale, NV

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-15

...-0705; Airspace Docket No. 12-AWP-4] Establishment of Class E Airspace; Coaldale, NV AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action establishes Class E airspace... forth in the NPRM for lowering the Class E airspace down to 1,200 feet above the surface was vague and...

Reusable Rack Interface Controller Common Software for Various Science Research Racks on the International Space Station

NASA Technical Reports Server (NTRS)

Lu, George C.

2003-01-01

The purpose of the EXPRESS (Expedite the PRocessing of Experiments to Space Station) rack project is to provide a set of predefined interfaces for scientific payloads which allow rapid integration into a payload rack on International Space Station (ISS). VxWorks' was selected as the operating system for the rack and payload resource controller, primarily based on the proliferation of VME (Versa Module Eurocard) products. These products provide needed flexibility for future hardware upgrades to meet everchanging science research rack configuration requirements. On the International Space Station, there are multiple science research rack configurations, including: 1) Human Research Facility (HRF); 2) EXPRESS ARIS (Active Rack Isolation System); 3) WORF (Window Observational Research Facility); and 4) HHR (Habitat Holding Rack). The RIC (Rack Interface Controller) connects payloads to the ISS bus architecture for data transfer between the payload and ground control. The RIC is a general purpose embedded computer which supports multiple communication protocols, including fiber optic communication buses, Ethernet buses, EIA-422, Mil-Std-1553 buses, SMPTE (Society Motion Picture Television Engineers)-170M video, and audio interfaces to payloads and the ISS. As a cost saving and software reliability strategy, the Boeing Payload Software Organization developed reusable common software where appropriate. These reusable modules included a set of low-level driver software interfaces to 1553B. RS232, RS422, Ethernet buses, HRDL (High Rate Data Link), video switch functionality, telemetry processing, and executive software hosted on the FUC computer. These drivers formed the basis for software development of the HRF, EXPRESS, EXPRESS ARIS, WORF, and HHR RIC executable modules. The reusable RIC common software has provided extensive benefits, including: 1) Significant reduction in development flow time; 2) Minimal rework and maintenance; 3) Improved reliability; and 4) Overall reduction in software life cycle cost. Due to the limited number of crew hours available on ISS for science research, operational efficiency is a critical customer concern. The current method of upgrading RIC software is a time consuming process; thus, an improved methodology for uploading RIC software is currently under evaluation.

NREL Evaluates Performance of Fast-Charge Electric Buses

DOE Office of Scientific and Technical Information (OSTI.GOV)

2016-09-16

This real-world performance evaluation is designed to enhance understanding of the overall usage and effectiveness of electric buses in transit operation and to provide unbiased technical information to other agencies interested in adding such vehicles to their fleets. Initial results indicate that the electric buses under study offer significant fuel and emissions savings. The final results will help Foothill Transit optimize the energy-saving potential of its transit fleet. NREL's performance evaluations help vehicle manufacturers fine-tune their designs and help fleet managers select fuel-efficient, low-emission vehicles that meet their bottom line and operational goals. help Foothill Transit optimize the energy-saving potentialmore » of its transit fleet. NREL's performance evaluations help vehicle manufacturers fine-tune their designs and help fleet managers select fuel-efficient, low-emission vehicles that meet their bottom line and operational goals.« less

Photonic Integrated Circuits

NASA Technical Reports Server (NTRS)

Krainak, Michael; Merritt, Scott

2016-01-01

Integrated photonics generally is the integration of multiple lithographically defined photonic and electronic components and devices (e.g. lasers, detectors, waveguides passive structures, modulators, electronic control and optical interconnects) on a single platform with nanometer-scale feature sizes. The development of photonic integrated circuits permits size, weight, power and cost reductions for spacecraft microprocessors, optical communication, processor buses, advanced data processing, and integrated optic science instrument optical systems, subsystems and components. This is particularly critical for small spacecraft platforms. We will give an overview of some NASA applications for integrated photonics.

Cycle Tracks and Parking Environments in China: Learning from College Students at Peking University

PubMed Central

Yuan, Changzheng; Sun, Yangbo; Lv, Jun; Lusk, Anne C.

2017-01-01

China has a historic system of wide cycle tracks, many of which are now encroached by cars, buses and bus stops. Even with these conditions, college students still bicycle. On campuses, students park their bikes on facilities ranging from kick-stand-plazas to caged sheds with racks, pumps and an attendant. In other countries, including Canada, some of the newer cycle tracks need to be wider to accommodate an increasing number of bicyclists. Other countries will also need to improve their bike parking, which includes garage-basement cages and two-tiered racks. China could provide lessons about cycle tracks and bike parking. This study applied the Maslow Transportation Level of Service (LOS) theory, i.e., for cycle tracks and bike parking, only after the basic needs of safety and security are met for both vehicle occupants and bicyclists can the higher needs of convenience and comfort be met. With random clustering, a self-administered questionnaire was collected from 410 students in six dormitory buildings at Peking University in Beijing and an environmental scan of bicycle parking conducted in school/office and living areas. Cycle tracks (1 = very safe/5 = very unsafe) shared with moving cars were most unsafe (mean = 4.6), followed by sharing with parked cars (4.1) or bus stop users (4.1) (p < 0.001). Close to half thought campus bike parking lacked order. The most suggested parking facilities were sheds, security (guard or camera), bicycle racks and bicycle parking services (pumps, etc.). If parking were improved, three quarters indicated they would bicycle more. While caged sheds were preferred, in living areas with 1597 parked bikes, caged sheds were only 74.4% occupied. For the future of China’s wide cycle tracks, perhaps a fence-separated bus lane beside a cycle track might be considered or, with China’s recent increase in bike riding, shared bikes and E-bikes, perhaps cars/buses could be banned from the wide cycle tracks. In other countries, a widened cycle track entrance should deter cars. Everywhere, bike parking sheds could be built and redesigned with painted lines to offer more space and order, similar to car parking. PMID:28820463

Cycle Tracks and Parking Environments in China: Learning from College Students at Peking University.

PubMed

Yuan, Changzheng; Sun, Yangbo; Lv, Jun; Lusk, Anne C

2017-08-18

China has a historic system of wide cycle tracks, many of which are now encroached by cars, buses and bus stops. Even with these conditions, college students still bicycle. On campuses, students park their bikes on facilities ranging from kick-stand-plazas to caged sheds with racks, pumps and an attendant. In other countries, including Canada, some of the newer cycle tracks need to be wider to accommodate an increasing number of bicyclists. Other countries will also need to improve their bike parking, which includes garage-basement cages and two-tiered racks. China could provide lessons about cycle tracks and bike parking. This study applied the Maslow Transportation Level of Service (LOS) theory, i.e., for cycle tracks and bike parking, only after the basic needs of safety and security are met for both vehicle occupants and bicyclists can the higher needs of convenience and comfort be met. With random clustering, a self-administered questionnaire was collected from 410 students in six dormitory buildings at Peking University in Beijing and an environmental scan of bicycle parking conducted in school/office and living areas. Cycle tracks (1 = very safe/5 = very unsafe) shared with moving cars were most unsafe (mean = 4.6), followed by sharing with parked cars (4.1) or bus stop users (4.1) ( p < 0.001). Close to half thought campus bike parking lacked order. The most suggested parking facilities were sheds, security (guard or camera), bicycle racks and bicycle parking services (pumps, etc.). If parking were improved, three quarters indicated they would bicycle more. While caged sheds were preferred, in living areas with 1597 parked bikes, caged sheds were only 74.4% occupied. For the future of China's wide cycle tracks, perhaps a fence-separated bus lane beside a cycle track might be considered or, with China's recent increase in bike riding, shared bikes and E-bikes, perhaps cars/buses could be banned from the wide cycle tracks. In other countries, a widened cycle track entrance should deter cars. Everywhere, bike parking sheds could be built and redesigned with painted lines to offer more space and order, similar to car parking.

An Analysis of Challenges Faced by Students Learning in Virtual and Open Distance Learning System: A Case of Bindura University of Science Education (BUSE)

ERIC Educational Resources Information Center

Dodo, Obediah; Makwerere, David; Parwada, Matavire; Parwada, Cosmas

2013-01-01

After realizing that the traditional modes of tuition in Zimbabwe's andragogy had either gone obsolete or over-crowded, BUSE ventured into a "virtualised" model of open and distance learning as a way of out-doing other competing universities. However, as the programme was rolled out, there came a myriad of challenges affecting the…

Concerns of the Institute of Transport Study and Research for reducing the sound level inside completely repaired buses. [noise and vibration control

NASA Technical Reports Server (NTRS)

Groza, A.; Calciu, J.; Nicola, I.; Ionasek, A.

1974-01-01

Sound level measurements on noise sources on buses are used to observe the effects of attenuating acoustic pressure levels inside the bus by sound-proofing during complete repair. A spectral analysis of the sound level as a function of motor speed, bus speed along the road, and the category of the road is reported.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kattke, Michele D.; Chan, Albert H.; Duong, Andrew

Here, many species of Gram-positive bacteria use sortase transpeptidases to covalently affix proteins to their cell wall or to assemble pili. Sortase-displayed proteins perform critical and diverse functions for cell survival, including cell adhesion, nutrient acquisition, and morphological development, among others. Based on their amino acid sequences, there are at least six types of sortases (class A to F enzymes); however, class E enzymes have not been extensively studied. Class E sortases are used by soil and freshwater-dwelling Actinobacteria to display proteins that contain a non-canonical LAXTG sorting signal, which differs from 90% of known sorting signals by substitution ofmore » alanine for proline. Here we report the first crystal structure of a class E sortase, the 1.93 Å resolution structure of the SrtE1 enzyme from Streptomyces coelicolor. The active site is bound to a tripeptide, providing insight into the mechanism of substrate binding. SrtE1 possesses β3/β4 and β6/β7 active site loops that contact the LAXTG substrate and are structurally distinct from other classes. We propose that SrtE1 and other class E sortases employ a conserved tyrosine residue within their β3/β4 loop to recognize the amide nitrogen of alanine at position P3 of the sorting signal through a hydrogen bond, as seen here. Incapability of hydrogen-bonding with canonical proline-containing sorting signals likely contributes to class E substrate specificity. Furthermore, we demonstrate that surface anchoring of proteins involved in aerial hyphae formation requires an N-terminal segment in SrtE1 that is presumably positioned within the cytoplasm. Combined, our results reveal unique features within class E enzymes that enable them to recognize distinct sorting signals, and could facilitate the development of substrate-based inhibitors of this important enzyme family.« less

49 CFR 37.213 - Information collection requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Information collection requirements. 37.213 Section 37.213 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.213 Information collection requirements...

49 CFR 37.207 - Discriminatory practices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Discriminatory practices. 37.207 Section 37.207 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.207 Discriminatory practices. It shall be considered...

78 FR 40546 - Nissan North America, Incorporated, Receipt of Petition for Decision of Inconsequential...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-05

..., buses or multipurpose passenger vehicles (MPVs) manufactured from December 20, 2010 to July 17, 2012, do not fully comply with paragraph S3.1.4.1 of Federal Motor Vehicle Safety Standard (FMVSS) No. 102, Transmission Shift Position Sequence, Starter Interlock, and Transmission Braking Effect. Nissan has filed an...

49 CFR 393.55 - Antilock brake systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 57396, Sept. 21, 2010. (a) Hydraulic brake systems. Each truck and bus manufactured on or after March 1, 1999 (except trucks and buses engaged in driveaway-towaway operations), and equipped with a hydraulic... FMVSS No. 105 (49 CFR 571.105, S5.3). (c) Air brake systems. (1) Each truck tractor manufactured on or...

49 CFR 571.302 - Standard No. 302; Flammability of interior materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... materials. S1. Scope. This standard specifies burn resistance requirements for materials used in the... to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3A. Definitions. Occupant... in accordance with S5, material described in S4.1 and S4.2 shall not burn, nor transmit a flame front...

49 CFR 571.302 - Standard No. 302; Flammability of interior materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... materials. S1. Scope. This standard specifies burn resistance requirements for materials used in the... to passenger cars, multipurpose passenger vehicles, trucks, and buses. S3A. Definitions. Occupant... in accordance with S5, material described in S4.1 and S4.2 shall not burn, nor transmit a flame front...

Using Facebook™ to recruit college-age men for a Human Papillomavirus vaccine trial

PubMed Central

Raviotta, Jonathan M.; Nowalk, Mary Patricia; Lin, Chyongchiou Jeng; Huang, Hsin-Hui; Zimmerman, Richard K.

2015-01-01

Background College-age men were recruited using Facebook™ advertisements (ads), as well as traditional recruitment methods, for a randomized controlled trial to compare immunological responses to human papilloma virus (HPV) vaccine administered in two dosing schedules. This study compares enrollees who were recruited through traditional recruitment methods vs. social networking sites including Facebook™. Methods Potential participants were recruited using fliers posted on and off campus(es), and distributed at health fairs, classes, sporting and other campus events; e-mails to students and student organizations; and print advertisements in student newspapers and on city buses. Facebook™ ads were displayed to users with specific age, geographic, and interest characteristics; ads were monitored daily to make adjustments to improve response. Results 220 males, ages 18–25 years enrolled between October 2010 and May 2011. The majority of participants (51%) reported print advertisements as the method by which they first heard about the study, followed by personal contact (29%) and Facebook™ or other social networking site (SNS; 20%). The likelihood of SNS being the source by which the participant first heard about the study compared with traditional methods was increased if the participant reported: 1) being homosexual or bisexual; or 2) posting daily updates on SNS. Conclusions Facebook™ and other social networking sites are a viable recruitment strategy for reaching potential clinical trial participants among groups who typically use social media to stay connected with their friends and hard-to-reach groups such as young men who self-identify as homosexual or bisexual. PMID:25389213

Class E/F switching power amplifiers

NASA Technical Reports Server (NTRS)

Hajimiri, Seyed-Ali (Inventor); Aoki, Ichiro (Inventor); Rutledge, David B. (Inventor); Kee, Scott David (Inventor)

2004-01-01

The present invention discloses a new family of switching amplifier classes called class E/F amplifiers. These amplifiers are generally characterized by their use of the zero-voltage-switching (ZVS) phase correction technique to eliminate of the loss normally associated with the inherent capacitance of the switching device as utilized in class-E amplifiers, together with a load network for improved voltage and current wave-shaping by presenting class-F.sup.-1 impedances at selected overtones and class-E impedances at the remaining overtones. The present invention discloses a several topologies and specific circuit implementations for achieving such performance.

Analysis and design of continuous class-E power amplifier at sub-nominal condition

NASA Astrophysics Data System (ADS)

Chen, Peng; Yang, Kai; Zhang, Tianliang

2017-12-01

The continuous class-E power amplifier at sub-nominal condition is proposed in this paper. The class-E power amplifier at continuous mode means it can be high efficient on a series matching networks while at sub-nominal condition means it only requires the zero-voltage-switching condition. Comparing with the classical class-E power amplifier, the proposed design method releases two additional design freedoms, which increase the class-E power amplifier's design flexibility. Also, the proposed continuous class-E power amplifier at sub-nominal condition can perform high efficiency over a broad bandwidth. The performance study of the continuous class-E power amplifier at sub-nominal condition is derived and the design procedure is summarised. The normalised switch voltage and current waveforms are investigated. Furthermore, the influences of different sub-nominal conditions on the power losses of the switch-on resistor and the output power capability are also discussed. A broadband continuous class-E power amplifier based on a Gallium Nitride (GaN) transistor is designed and testified to verify the proposed design methodology. The measurement results show, it can deliver 10-15 W output power with 64-73% power-added efficiency over 1.4-2.8 GHz.

Does the air condition system in busses spread allergic fungi into driver space?

PubMed

Sowiak, Małgorzata; Kozajda, Anna; Jeżak, Karolina; Szadkowska-Stańczyk, Irena

2018-02-01

The aim of this study was to establish whether the air-conditioning system in buses constitutes an additional source of indoor air contamination with fungi, and whether or not the fungi concentration depends on the period from the last disinfection of the system, combined with replacement of the cabin dust particle filter. The air samples to fungi analysis using impact method were taken in 30 buses (20 with an air-conditioning system, ACS; 10 with a ventilation system, VS) in two series: 1 and 22 weeks after cabin filter replacement and disinfection of the air-conditioning system. During one test in each bus were taken two samples: before the air-conditioning or ventilation system switched on and 6 min after operating of these systems. The atmospheric air was the external background (EB). After 1 week of use of the system, the fungi concentrations before starting of the ACS and VS system were 527.8 and 1053.0 cfu/m 3 , respectively, and after 22 weeks the concentrations were 351.9 and 1069.6 cfu/m 3 , respectively. While in the sample after 6 min of ACS and VS system operating, the fungi concentration after 1 week of use was 127.6 and 233.7 cfu/m 3 , respectively, and after 22 weeks it was 113.3 and 324.9 cfu/m 3 , respectively. Results do not provide strong evidence that air-conditioning system is an additional source of indoor air contamination with fungi. A longer operation of the system promoted increase of fungi concentration in air-conditioned buses only.

[Seatbelts on school buses: are they safe for our children?].

PubMed

Peleg, Kobi; Goldman, Sharon

2008-01-01

In Israel, 280,000 pupils travel daily to school and back home by means of school transportation. In an effort to increase school transportation safety, the installation of lap belts in school transportation vehicles is required since September 1, 2006. In Israel, laws are often passed with good intentions, but frequently without exploring the potential outcomes. Traffic regulation 364a states that "lap belts or other seatbelts" are required in all vehicles used for school transportation. The objective of this study is to review the world-wide literature regarding seatbelts on school buses with an emphasis to identify the risks associated with lap restraints. Over 50 studies, articles and position papers referring to the efficacy of seatbelts, with an emphasis on school transportation, were reviewed. According to the literature, this new traffic regulation could produce more devastating outcomes than previously. Seatbelts were designed to prevent passenger injuries during a motor vehicle crash. Researchers have not proven efficacy of seatbelts in school buses. Lap-only belts have shown to increase the risk of severe injury among children, even in mild crashes. Since young children are not adequately developed to take the force of a lap-only restraint, these belts have been associated with internal injuries, lumbar fracture-dislocations, abdominal contusions and head injuries. The National Highway Traffic Safety Administration (NHTSA) in the USA has reported that lap belts are not effective in preventing injury among children traveling by bus. Children have a two to three fold risk of severe injury when using lap only restraints. On the contrary, lap-shoulder belts may reduce the risk of abdominal injuries by up to 50% relative to lap-only belts. In conclusion, policy makers aimed to implement regulations which will reduce injuries and fatalities. However, neglecting to carry out an in-depth professional review has brought about a regulation requiring lap belts in school buses; a decision which, according to international research studies, can potentially increase the injury risks among pupils.

Idle emissions from heavy-duty diesel and natural gas vehicles at high altitude.

PubMed

McCormick, R L; Graboski, M S; Alleman, T L; Yanowitz, J

2000-11-01

Idle emissions of total hydrocarbon (THC), CO, NOx, and particulate matter (PM) were measured from 24 heavy-duty diesel-fueled (12 trucks and 12 buses) and 4 heavy-duty compressed natural gas (CNG)-fueled vehicles. The volatile organic fraction (VOF) of PM and aldehyde emissions were also measured for many of the diesel vehicles. Experiments were conducted at 1609 m above sea level using a full exhaust flow dilution tunnel method identical to that used for heavy-duty engine Federal Test Procedure (FTP) testing. Diesel trucks averaged 0.170 g/min THC, 1.183 g/min CO, 1.416 g/min NOx, and 0.030 g/min PM. Diesel buses averaged 0.137 g/min THC, 1.326 g/min CO, 2.015 g/min NOx, and 0.048 g/min PM. Results are compared to idle emission factors from the MOBILE5 and PART5 inventory models. The models significantly (45-75%) overestimate emissions of THC and CO in comparison with results measured from the fleet of vehicles examined in this study. Measured NOx emissions were significantly higher (30-100%) than model predictions. For the pre-1999 (pre-consent decree) truck engines examined in this study, idle NOx emissions increased with model year with a linear fit (r2 = 0.6). PART5 nationwide fleet average emissions are within 1 order of magnitude of emissions for the group of vehicles tested in this study. Aldehyde emissions for bus idling averaged 6 mg/min. The VOF averaged 19% of total PM for buses and 49% for trucks. CNG vehicle idle emissions averaged 1.435 g/min for THC, 1.119 g/min for CO, 0.267 g/min for NOx, and 0.003 g/min for PM. The g/min PM emissions are only a small fraction of g/min PM emissions during vehicle driving. However, idle emissions of NOx, CO, and THC are significant in comparison with driving emissions.

Comparison of life cycle greenhouse gases from natural gas pathways for medium and heavy-duty vehicles.

PubMed

Tong, Fan; Jaramillo, Paulina; Azevedo, Inês M L

2015-06-16

The low-cost and abundant supply of shale gas in the United States has increased the interest in using natural gas for transportation. We compare the life cycle greenhouse gas (GHG) emissions from different natural gas pathways for medium and heavy-duty vehicles (MHDVs). For Class 8 tractor-trailers and refuse trucks, none of the natural gas pathways provide emissions reductions per unit of freight-distance moved compared to diesel trucks. When compared to the petroleum-based fuels currently used in these vehicles, CNG and centrally produced LNG increase emissions by 0-3% and 2-13%, respectively, for Class 8 trucks. Battery electric vehicles (BEVs) powered with natural gas-produced electricity are the only fuel-technology combination that achieves emission reductions for Class 8 transit buses (31% reduction compared to the petroleum-fueled vehicles). For non-Class 8 trucks (pick-up trucks, parcel delivery trucks, and box trucks), BEVs reduce emissions significantly (31-40%) compared to their diesel or gasoline counterparts. CNG and propane achieve relatively smaller emissions reductions (0-6% and 19%, respectively, compared to the petroleum-based fuels), while other natural gas pathways increase emissions for non-Class 8 MHDVs. While using natural gas to fuel electric vehicles could achieve large emission reductions for medium-duty trucks, the results suggest there are no great opportunities to achieve large emission reductions for Class 8 trucks through natural gas pathways with current technologies. There are strategies to reduce the carbon footprint of using natural gas for MHDVs, ranging from increasing vehicle fuel efficiency, reducing life cycle methane leakage rate, to achieving the same payloads and cargo volumes as conventional diesel trucks.

Crossing Guards: A Safety Patrol Program at a Residential School for Students Who Are Blind or Visually Impaired. Practice Report

ERIC Educational Resources Information Center

Besden, Cheryl; Crow, Nita; Delgado Greenberg, Maya; Finkelstein, Gerri; Shrieves, Gary; Vickroy, Marcia

2005-01-01

In 2001, the California School for the Blind (CSB) was faced with a dilemma. The dropoff point for the day buses had to be changed. The new route to the only logical location for this change sent the buses through a driveway where residential students crossed to travel between the school and the dormitories. Some staff members wanted to eliminate…

78 FR 70415 - Federal Motor Vehicle Safety Standards; Occupant Crash Protection

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-25

...Completing the first initiative of NHTSA's 2007 ``NHTSA's Approach to Motorcoach Safety'' plan and one of the principal undertakings of DOT's 2009 Motorcoach Safety Action Plan, and fulfilling a statutory mandate of the Motorcoach Enhanced Safety Act of 2012, incorporated into the Moving Ahead for Progress in the 21st Century Act, this final rule amends the Federal motor vehicle safety standard (FMVSS) on occupant crash protection to require lap/shoulder seat belts for each passenger seating position in all new over-the-road buses, and in new buses other than over-the-road buses with a gross vehicle weight rating (GVWR) greater than 11,793 kilograms (kg) (26,000 pounds (lb), with certain exclusions. By requiring the passenger lap/ shoulder seat belts, this final rule significantly reduces the risk of fatality and serious injury in frontal crashes and the risk of occupant ejection in rollovers, thus considerably enhancing the safety of these vehicles.

Performance Evaluation of UHF RFID Technologies for Real-Time Bus Recognition in the Taipei Bus Station

PubMed Central

Own, Chung-Ming; Lee, Da-Sheng; Wang, Ti-Ho; Wang, De-Jun; Ting, Yu-Lun

2013-01-01

Transport stations such as airports, ports, and railways have adopted blocked-type pathway management to process and control travel systems in a one-directional manner. However, this excludes highway transportation where large buses have great variability and mobility; thus, an instant influx of numerous buses increases risks and complicates station management. Focusing on Taipei Bus Station, this study employed RFID technology to develop a system platform integrated with modern information technology that has numerous characteristics. This modern information technology comprised the following systems: ultra-high frequency (UHF) radio-frequency identification (RFID), ultrasound and license number identification, and backstage graphic controls. In conclusion, the system enabled management, bus companies, and passengers to experience the national bus station's new generation technology, which provides diverse information and synchronization functions. Furthermore, this technology reached a new milestone in the energy-saving and efficiency-increasing performance of Taiwan's buses. PMID:23778192

Hybrid Turbine Electric Vehicle

NASA Technical Reports Server (NTRS)

Viterna, Larry A.

1997-01-01

Hybrid electric power trains may revolutionize today's ground passenger vehicles by significantly improving fuel economy and decreasing emissions. The NASA Lewis Research Center is working with industry, universities, and Government to develop and demonstrate a hybrid electric vehicle. Our partners include Bowling Green State University, the Cleveland Regional Transit Authority, Lincoln Electric Motor Division, the State of Ohio's Department of Development, and Teledyne Ryan Aeronautical. The vehicle will be a heavy class urban transit bus offering double the fuel economy of today's buses and emissions that are reduced to 1/10th of the Environmental Protection Agency's standards. At the heart of the vehicle's drive train is a natural-gas-fueled engine. Initially, a small automotive engine will be tested as a baseline. This will be followed by the introduction of an advanced gas turbine developed from an aircraft jet engine. The engine turns a high-speed generator, producing electricity. Power from both the generator and an onboard energy storage system is then provided to a variable-speed electric motor attached to the rear drive axle. An intelligent power-control system determines the most efficient operation of the engine and energy storage system.

Alternative Fuels Data Center: Kansas Transportation Data for Alternative

Science.gov Websites

Renzenberger Inc Saves Money With Propane Vans Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Save Money Natural Gas School Buses Help Kansas City Save Money Nov. 12, 2011 https://www.youtube.com

49 CFR 37.187 - Interline service.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Interline service. 37.187 Section 37.187 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.187 Interline service. (a) When the general public can...

49 CFR 37.193 - Interim service requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Interim service requirements. 37.193 Section 37.193 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.193 Interim service requirements. (a) Until...

49 CFR 37.181 - Applicability dates.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Applicability dates. 37.181 Section 37.181 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.181 Applicability dates. This subpart applies to all...

49 CFR 37.197 - Remanufactured OTRBs.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Remanufactured OTRBs. 37.197 Section 37.197 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.197 Remanufactured OTRBs. (a) This section applies to any...

49 CFR 37.181 - Applicability dates.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 1 2011-10-01 2011-10-01 false Applicability dates. 37.181 Section 37.181 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.181 Applicability dates. This subpart applies to all...

High performance 1553

NASA Astrophysics Data System (ADS)

Hegarty, Michael G.

2005-05-01

The U.S. Air Force is currently in the process of developing a revision to MIL-STD-1553 that will provide additional digital communication bandwidth beyond MIL-STD-1553B's 1 Megabit per second (Mbps) rate. The proposed revision to MIL-STD-1553 (referred to as MIL-STD-1553C) is targeting 200 Mbps as a baseline data rate. This paper explores the feasibility of the U.S. Air Force's proposed revision to MIL-STD-1553 based on studies conducted by Data Device Corporation (DDC). A combination of empirical and theoretical methods is used to determine if a MIL-STD-1553B network contains sufficient capacity to support the proposed 200 Mbps data rate. The results of DDC's analysis is that for some MIL-STD-1553 buses there is sufficient bandwidth to implement a broadband system in which legacy 1 Mbps 1553B waveforms could coexist with new 200 Mbps waveforms, thus providing an incremental high speed communication channel to existing MIL-STD-1553 buses.

77 FR 39653 - Proposed Establishment of Class E Airspace; Reidsville, GA, and Proposed Amendment of Class E...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-05

... at Reidsville, GA. Separation of existing Class E airspace surrounding Swinton Smith Field at... the surface at Swinton Smith Field at Reidsville Municipal Airport (formerly Reidsville Airport... CFR, 1959-1963 Comp., p. 389. Sec. 71.1 [Amended] 2. The incorporation by reference in 14 CFR 71.1 of...

Delay correction model for estimating bus emissions at signalized intersections based on vehicle specific power distributions.

PubMed

Song, Guohua; Zhou, Xixi; Yu, Lei

2015-05-01

The intersection is one of the biggest emission points for buses and also the high exposure site for people. Several traffic performance indexes have been developed and widely used for intersection evaluations. However, few studies have focused on the relationship between these indexes and emissions at intersections. This paper intends to propose a model that relates emissions to the two commonly used measures of effectiveness (i.e. delay time and number of stops) by using bus activity data and emission data at intersections. First, with a large number of field instantaneous emission data and corresponding activity data collected by the Portable Emission Measurement System (PEMS), emission rates are derived for different vehicle specific power (VSP) bins. Then, 2002 sets of trajectory data, an equivalent of about 140,000 sets of second-by-second activity data, are obtained from Global Position Systems (GPSs)-equipped diesel buses in Beijing. The delay and the emission factors of each trajectory are estimated. Then, by using baseline emission factors for two types of intersections, e.g. the Arterial @ Arterial Intersection and the Arterial @ Collector, delay correction factors are calculated for the two types of intersections at different congestion levels. Finally, delay correction models are established for adjusting emission factors for each type of intersections and different numbers of stops. A comparative analysis between estimated and field emission factors demonstrates that the delay correction model is reliable. Copyright © 2015 Elsevier B.V. All rights reserved.

Alternative Fuels Data Center: CNG Shuttles Save Fuel Costs for R&R

Science.gov Websites

Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels Vehicles With Natural Gas Oct. 1, 2011 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June 18, 2010 Fisher Coachworks Develops Plug

Alternative Fuels Data Center: Michigan Converts Vehicles to Propane,

Science.gov Websites

, Reducing Emissions Learn how Detroit reduces emissions and saves money by converting vehicles to run on , 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Photo of an electric vehicle at a Natural Gas Fueling Stations July 1, 2010 Hybrid Electric Shuttle Buses Offer Free Rides in Maryland June

78 FR 59090 - Nissan North America, Incorporated, Grant of Petition for Decision of Inconsequential Noncompliance

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-25

... alert a driver exiting the vehicle if the key remained in the starting system. Furthermore, if the..., buses or multipurpose passenger vehicles (MPVs) manufactured from December 20, 2010 to July 17, 2012, do not fully comply with paragraph S3.1.4.1 of Federal Motor Vehicle Safety Standard (FMVSS) No. 102...

Commercial Passenger Vehicles: Safety Inspection of Commercial Buses and Vans Entering into the United States from Mexico

DOT National Transportation Integrated Search

1997-08-08

In response to concerns about whether commercial passenger vehicles entering the United States from Mexico are meeting U.S. safety standards, this report describes (1) the number and types of commercial passenger vehicles entering U.S. border states ...

49 CFR 37.205 - Additional passengers who use wheelchairs.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Additional passengers who use wheelchairs. 37.205 Section 37.205 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.205 Additional passengers who use...

49 CFR 37.215 - Review of requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Review of requirements. 37.215 Section 37.215 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.215 Review of requirements. (a) Beginning October 28, 2005...

49 CFR 38.35 - Public information system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Public information system. 38.35 Section 38.35... SPECIFICATIONS FOR TRANSPORTATION VEHICLES Buses, Vans and Systems § 38.35 Public information system. (a... a public address system permitting the driver, or recorded or digitized human speech messages, to...

49 CFR 37.213 - Information collection requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Analysis & Information System 1200 New Jersey Avenue, SE., Washington, D.C. 20590. [66 FR 9053, Feb. 6... 49 Transportation 1 2011-10-01 2011-10-01 false Information collection requirements. 37.213... INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.213 Information collection requirements...

The Impact of Staffing on Program Efficiency.

ERIC Educational Resources Information Center

Farmer, Ernest

1988-01-01

Adequate staffing for pupil transportation provides for the following: (1) drivers are appropriately instructed; (2) school buses meet the highest standards of construction and maintenance; (3) discipline is uniformly administered; (4) instruction in safe riding practices is provided; and (5) salary and fringe benefits retain the best qualified…

Prevalence and Characterization of β-Lactamases Genes and Class 1 Integrons in Multidrug-Resistant Escherichia coli Isolates from Chicken Meat in Korea.

PubMed

Seo, Kwang Won; Lee, Young Ju

2018-06-21

Antimicrobial resistance has become a serious public health threat throughout the world, and therapeutic options for several infectious diseases are currently limited by the presence of multidrug-resistant (MDR) bacteria. This study was designed to examine the drug resistance patterns, the prevalence of the β-lactamases, and class 1 integrons in MDR Escherichia coli isolates from chicken meat in Korea. Among 200 chicken meat samples, 101 isolates were observed to be positive for E. coli, of which 57 were identified as MDR E. coli. Among 57 MDR E. coli isolates, the prevalence of bla gene, bla CTX-M-1 , bla CTX-M-14 , and bla TEM-1 , were identified in 2, 4, and 16 E. coli strains, respectively; only 1 E. coli strain had both, bla TEM-1 and bla CTX-M-1 genes. Twenty-one of the 57 MDR E. coli isolates also carried class 1 integrons, and 5 different gene cassette arrangements were found in 14 of the 21 class 1 integron-positive isolates. The β-lactamase-producing E. coli and integron-positive E. coli had significantly higher resistance to 16 antimicrobial drugs than the non-β-lactamase-producing E. coli and the integron-negative E. coli (p < 0.05). Our findings suggest that β-lactamase and class 1 integrons are widely distributed in E. coli isolates from chicken meat, and directly contribute to resistance to diverse antimicrobial agents. Therefore, continuous investigation of integron gene cassette arrays will provide useful information regarding antimicrobial resistance mechanisms.

76 FR 18040 - Amendment of Class E Airspace; West Yellowstone, MT

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-01

... reference action under 1 CFR Part 51, subject to the annual revision of FAA Order 7400.9 and publication of... CLASS A, B, C, D AND E AIRSPACE AREAS; AIR TRAFFIC SERVICE ROUTES; AND REPORTING POINTS 0 1. The... follows: Paragraph 6005 Class E airspace areas extending upward from 700 feet or more above the surface of...

Black carbon and polycyclic aromatic hydrocarbon emissions from vehicles in the United States-Mexico border region: pilot study.

PubMed

Kelly, Kerry; Wagner, David; Lighty, JoAnn; Quintero Núñez, Margarito; Vazquez, F Adrian; Collins, Kimberly; Barud-Zubillaga, Alberto

2006-03-01

The investigators developed a system to measure black carbon (BC) and particle-bound polycyclic aromatic hydrocarbon (PAH) emission factors during roadside sampling in four cities along the United States-Mexico border, Calexico/Mexicali and El Paso/Juarez. The measurement system included a photoacoustic analyzer for BC, a photoelectric aerosol sensor for particle-bound PAHs, and a carbon dioxide (CO2) analyzer. When a vehicle with measurable emissions passed the system probe, corresponding BC, PAH, and CO2 peaks were evident, and a fuel-based emission factor was estimated. A picture of each vehicle was also recorded with a digital camera. The advantage of this system, compared with other roadside methods, is the direct measurement of particulate matter components and limited interference from roadside dust. The study revealed some interesting trends: Mexican buses and all medium-duty trucks were more frequently identified as high emitters of BC and PAH than heavy-duty trucks or passenger vehicles. In addition, because of the high daily mileage of buses, they are good candidates for additional study. Mexican trucks and buses had higher average emission factors compared with U.S. trucks and buses, but the differences were not statistically significant. Few passenger vehicles had measurable BC and PAH emissions, although the highest emission factor came from an older model passenger vehicle licensed in Baja California.

Prevalence and pattern of occupational exposure to whole body vibration in Great Britain: findings from a national survey

PubMed Central

Palmer, K.; Griffin, M.; Bendall, H.; Pannett, B.; Coggon, D.

2000-01-01

OBJECTIVES—To estimate the number of workers in Great Britain with significant occupational exposure to whole body vibration (WBV) and to identify the common sources of exposure and the occupations and industries where such exposures arise.
METHODS—A postal questionnaire was posted to a random community sample of 22 194 men and women of working age. Among other things, the questionnaire asked about exposure to WBV in the past week, including occupational and common non-occupational sources. Responses were assessed by occupation and industry, and national prevalence estimates were derived from census information. Estimates were also made of the average estimated daily personal dose of vibration (eVDV).
RESULTS—From the 12 907 responses it was estimated that 7.2 million men and 1.8 million women in Great Britain are exposed to WBV at work in a 1 week period if the occupational use of cars, vans, buses, trains, and motor cycles is included within the definition of exposure. The eVDV of >374 000 men and 9000 women was estimated to exceed a proposed British Standard action level of 15 ms-1.75. Occupations in which the estimated exposures most often exceeded 15 ms-1.75 included forklift truck and mechanical truck drivers, farm owners and managers, farm workers, and drivers of road goods vehicles. These occupations also contributed the largest estimated numbers of workers in Great Britain with such levels of exposure. The highest estimated median occupational eVDVs were found in forklift truck drivers, drivers of road goods vehicles, bus and coach drivers, and technical and wholesale sales representatives, among whom a greater contribution to total dose was received from occupational exposures than from non-occupational ones; but in many other occupations the reverse applied. The most common sources of occupational exposure to WBV are cars, vans, forklift trucks, lorries, tractors, buses, and loaders.
CONCLUSIONS—Exposure to whole body vibration is common, but only a small proportion of exposures exceed the action level proposed in British standards, and in many occupations, non-occupational sources are more important than those at work. The commonest occupational sources of WBV and occupations with particularly high exposures have been identified, providing a basis for targeting future control activities.


Keywords: whole body vibration; population; prevalence; exposure PMID:10810108

Exhaust emissions from engines of the Detroit Diesel Corporation in transit buses: a decade of trends.

PubMed

Prucz, J C; Clark, N N; Gautam, M; Lyons, D W

2001-05-01

In the U.S.A., exhaust emissions from city buses fueled by diesel are not characterized well because current emission standards require engine tests rather than tests of whole vehicles. Two transportable chassis dynamometer laboratories developed and operated by West Virginia University (WVU) have been used extensively to gather realistic emission data from heavy-duty vehicles, including buses, tested in simulated driving conditions. A subset of these data has been utilized for a comprehensive introspection into the trends of regulated emissions from transit buses over the last 7 years, which has been prompted by continuously tightening restrictions on one hand, along with remarkable technological progress, on the other hand. Two widely used models of diesel engines manufactured by the Detroit Diesel Corporation (DDC) have been selected as a case-study for such an overview, based on full-scale, on-site testing of actual city buses, driven in accordance with the SAE J1376 standard of a Commercial Business District (CBD) cycle. The results provide solid, quantitative evidence that most regulated emissions from engines produced by DDC have declined over the years, especially with the transition from the 6V-92TA to the Series 50 models. This improvement is remarkable mainly for the emissions of particulate matter (PM), that are lower by over 70%, on average, for the Series 50 engines, though the emissions of nitrogen oxides (NOx) exhibit a reversed trend, showing a degradation of about 6%, on average, with the transition from 6V-92TA to the Series 50 engines. The expected trend of decreasing emission levels with the model year of the engine is clear and consistent for particulate matter (PM), hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx), starting with the 1990 models, although it is not conclusive for carbon dioxide (CO2) emissions.

Commuters' exposure to particulate matter air pollution is affected by mode of transport, fuel type, and route.

PubMed

Zuurbier, Moniek; Hoek, Gerard; Oldenwening, Marieke; Lenters, Virissa; Meliefste, Kees; van den Hazel, Peter; Brunekreef, Bert

2010-06-01

Commuters are exposed to high concentrations of air pollutants, but little quantitative information is currently available on differences in exposure between different modes of transport, routes, and fuel types. The aim of our study was to assess differences in commuters' exposure to traffic-related air pollution related to transport mode, route, and fuel type. We measured particle number counts (PNCs) and concentrations of PM2.5 (particulate matter

49 CFR 37.203 - Lift maintenance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.203 Lift maintenance. (a) The entity shall establish a system of regular and frequent maintenance checks of lifts sufficient to determine if they are operative... 49 Transportation 1 2010-10-01 2010-10-01 false Lift maintenance. 37.203 Section 37.203...

Bus Training Handbook.

ERIC Educational Resources Information Center

Dorny, Audrea; Cole, ChiKay

This manual presents guidelines for teaching students with disabilities necessary skills for safe and independent travel on public buses. Six guidelines for teachers include: (1) participate in bus training; (2) use wise and intelligent judgment; (3) utilize the bus checklist; (4) know and teach bus rules; (5) know bus routes; and (6) know bus…

49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Seats, seat belt assemblies, and seat belt assembly anchorages. 393.93 Section 393.93 Transportation Other Regulations Relating to Transportation... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses...

49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Seats, seat belt assemblies, and seat belt assembly anchorages. 393.93 Section 393.93 Transportation Other Regulations Relating to Transportation... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses...

49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Seats, seat belt assemblies, and seat belt assembly anchorages. 393.93 Section 393.93 Transportation Other Regulations Relating to Transportation... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses...

49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Seats, seat belt assemblies, and seat belt assembly anchorages. 393.93 Section 393.93 Transportation Other Regulations Relating to Transportation... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses...

49 CFR 393.93 - Seats, seat belt assemblies, and seat belt assembly anchorages.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Seats, seat belt assemblies, and seat belt assembly anchorages. 393.93 Section 393.93 Transportation Other Regulations Relating to Transportation... § 393.93 Seats, seat belt assemblies, and seat belt assembly anchorages. (a) Buses—(1) Buses...

49 CFR 37.203 - Lift maintenance.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 1 2011-10-01 2011-10-01 false Lift maintenance. 37.203 Section 37.203... DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.203 Lift maintenance. (a) The entity shall establish a system of regular and frequent maintenance checks of lifts sufficient to determine if they are operative...

49 CFR 37.189 - Service requirement for OTRB demand-responsive systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Service requirement for OTRB demand-responsive systems. 37.189 Section 37.189 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.189 Service requirement...

49 CFR 37.191 - Special provision for small mixed-service operators.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Special provision for small mixed-service operators. 37.191 Section 37.191 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.191 Special provision for...

49 CFR 37.201 - Intermediate and rest stops.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Intermediate and rest stops. 37.201 Section 37.201 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Over-the-Road Buses (OTRBs) § 37.201 Intermediate and rest stops. (a) Whenever an OTRB makes...

Manual for School Administrators on Pupil Transportation.

ERIC Educational Resources Information Center

Tennessee State Dept. of Education, Nashville.

Guiding principles, state laws, and state board rules and regulations are covered, providing school administrators with a ready reference in the field of pupil transportation. Divided into three sections, the manual initially covers administrative procedures including--(1) the purchase of buses, (2) bus maintenance, (3) employment of drivers, (4)…

49 CFR 393.40 - Required brake systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... subpart. (2) Air brake systems. Buses, trucks and truck-tractors equipped with air brake systems and..., and 393.52 of this subpart. (4) Electric brake systems. Motor vehicles equipped with electric brake..., trucks and truck tractors manufactured on or after March 1, 1975, and trailers manufactured on or after...