DOE Office of Scientific and Technical Information (OSTI.GOV)
Elgowainy, Amgad; Han, Jeongwoo; Ward, Jacob
This study provides a comprehensive lifecycle analysis (LCA), or cradle-to-grave (C2G) analysis, of the cost and greenhouse gas (GHG) emissions of a variety of vehicle-fuel pathways, as well as the levelized cost of driving (LCD) and cost of avoided GHG emissions. This study also estimates the technology readiness levels (TRLs) of key fuel and vehicle technologies along the pathways. The C2G analysis spans a full portfolio of midsize light-duty vehicles (LDVs), including conventional internal combustion engine vehicles (ICEVs), flexible fuel vehicles (FFVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell electric vehiclesmore » (FCEVs). In evaluating the vehicle-fuel combinations, this study considers both low-volume and high-volume “CURRENT TECHNOLOGY” cases (nominally 2015) and a high-volume “FUTURE TECHNOLOGY” lower-carbon case (nominally 2025–2030). For the CURRENT TECHNOLOGY case, low-volume vehicle and fuel production pathways are examined to determine costs in the near term.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elgowainy, Amgad; Han, Jeongwoo; Ward, Jacob
This study provides a comprehensive life-cycle analysis (LCA), or cradle-to-grave (C2G) analysis, of the cost and greenhouse gas (GHG) emissions of a variety of vehicle-fuel pathways, as well as the levelized cost of driving (LCD) and cost of avoided GHG emissions. This study also estimates the technology readiness levels (TRLs) of key fuel and vehicle technologies along the pathways. The C2G analysis spans a full portfolio of midsize light-duty vehicles (LDVs), including conventional internal combustion engine vehicles (ICEVs), flexible fuel vehicles (FFVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell electric vehiclesmore » (FCEVs). In evaluating the vehicle-fuel combinations, this study considers both low-volume and high-volume “CURRENT TECHNOLOGY” cases (nominally 2015) and a high-volume “FUTURE TECHNOLOGY” lower-carbon case (nominally 2025–2030). For the CURRENT TECHNOLOGY case, low-volume vehicle and fuel production pathways are examined to determine costs in the near term.« less
Yang, Bo Ram; Kim, Ye-Jee; Kim, Mi-Sook; Jung, Sun-Young; Choi, Nam-Kyong; Hwang, Byungkwan; Park, Byung-Joo; Lee, Joongyub
2018-05-23
Zolpidem is one of the most frequently used hypnotics worldwide, but associations with serious adverse effects such as motor vehicle collisions have been reported. The objective of this study was to evaluate the association of fatal motor vehicle collisions with a prescription for zolpidem, considering the context of the motor vehicle collisions. We conducted a case-crossover study, where each case served as its own control, by linking data about fatal motor vehicle collisions from the Korean Road Traffic Authority between 2010 and 2014 with national health insurance data. The case period was defined as 1 day before the fatal motor vehicle collisions, and was matched to four control periods at 90-day intervals. Conditional logistic regression was performed to calculate the odds ratio for fatal motor vehicle collisions associated with zolpidem exposure, and odds ratios were adjusted for time-varying exposure to confounding medications. A stratified analysis was performed by age group (younger than 65 years or not), the Charlson Comorbidity Index, and whether patients were new zolpidem users. Among the 714 subjects, the adjusted odds ratio for a fatal motor vehicle collision associated with a prescription for zolpidem the previous day was 1.48 (95% confidence interval 1.06-2.07). After stratification, a significantly increased risk was observed in subjects with a high Charlson Comorbidity Index (odds ratio 1.81; 95% confidence interval 1.16-2.84), the younger age group (odds ratio: 1.62; 95% confidence interval 1.03-2.56), and new zolpidem users (odds ratio 2.37; 95% confidence interval 1.40-4.00). A prescription for zolpidem on the previous day was significantly related to an increased risk of fatal motor vehicle collisions in this population-based case-crossover study.
Antilock brakes and the risk of driver injury in a crash: a case-control study.
Cummings, Peter; Grossman, David C
2007-09-01
While antilock brakes can improve steering and reduce stopping distance in some test situations, there is little evidence that they reduce the risk of crash-related injury. We sought to estimate the association between presence of antilock brakes and the risk of driver injury. We conducted a case-control study using claims data from the Insurance Corporation of British Columbia, Canada, for passenger vehicles insured during July 1, 2003, to June 30, 2004. Cases were 5000 vehicles with a driver crash injury during the study period. Controls were 49,994 vehicles insured at the mid-point of the study interval. The adjusted risk ratio for a crash with driver injury in a vehicle with antilock brakes was 1.06 (95% confidence interval, 0.95-1.17), compared with a vehicle without antilock brakes. If this estimated association is causal, antilock brakes do not prevent crash-related driver injuries.
Connected Vehicle Impacts on Transportation Planning—Outreach to Planning Community.
DOT National Transportation Integrated Search
2016-06-01
This document presents outreach memos on 11 case studies analyzing the impacts of connected and automated vehicles (C/AV) on transportation planning products. These 11 case studies are documented indepth in the associated project document entitled Co...
A case study of deer-vehicle accidents on I-64.
DOT National Transportation Integrated Search
1971-01-01
This case study of interstate fencing has indicated several findings which should be reviewed by the Virginia Department of Highways Environmental Quality Division. The major findings are: 1. Approximately 55 deer-vehicle collisions occurred on I-64 ...
IVHS institutional issues and case studies : Travtek case study
DOT National Transportation Integrated Search
1997-11-01
The U.S. Department of Transportation (USDOT) is embarking on a new program called the Intelligent Vehicle Initiative (IVI). The USDOT intends to jointly define the program plan and conduct the IVI in cooperation with the motor vehicle, trucking, and...
Motor vehicle-related burns: a review of 107 cases.
Papaevangelou, J; Batchelor, J S; Roberts, A H
1995-02-01
Motor vehicles are a major cause of morbidity and mortality. Burn injuries sustained from motor vehicles form a small but important subgroup. The authors have reviewed the case notes of 107 patients with motor vehicle-related burns over a 13-year period. The age ranged from 18 months to 65 years and the male to female ratio was 4:1. The mechanisms of injury were variable, although four major categories could be identified. These accounted for 83 per cent of the cases. Car fires following road traffic accidents was the largest group accounting for 48.5 per cent of cases. The remaining three groups were: motorcycle-related burns following road traffic accidents (6.5 per cent of cases), garage fire-related burns (15 per cent of cases) and car radiator-related burns (13 per cent of cases). Garage fire-related burns had the highest mortality of the four groups (25 per cent). This study demonstrated that garage fire burns are an important subgroup of motor vehicle-related burns.
Three dimensional modeling and dynamic analysis of four-wheel-steering vehicles
NASA Astrophysics Data System (ADS)
Hu, Haiyan; Han, Qiang
2003-02-01
The paper presents a nonlinear dynamic model of 9 degrees of freedom for four-wheel-steering vehicles. Compared with those in previous studies, this model includes the pitch and roll of the vehicle body, the motion of 4 wheels in the accelerating or braking process, the nonlinear coupling of vehicle body and unsprung part, as well as the air drag and wind effect. As a result, the model can be used for the analysis of various maneuvers of the four-wheel-steering vehicles. In addition, the previous models can be considered as a special case of this model. The paper gives some case studies for the dynamic performance of a four-wheel-steering vehicle under step input and saw-tooth input of steering angle applied on the front wheels, respectively.
Vehicle year and the risk of car crash injury
Blows, S; Ivers, R; Woodward, M; Connor, J; Ameratunga, S; Norton, R
2003-01-01
Objective: To quantify the association between vehicle age and risk of car crash injury. Design and setting: Data from a population based case-control study conducted in the Auckland region in 1998/99 was used to examine the adjusted risk of car crash injury or death due to vehicle age, after controlling for a range of known confounders. Cases were all cars involved in crashes in which at least one occupant was hospitalized or killed anywhere in the Auckland region, and controls were randomly selected cars on Auckland roads. The drivers of the 571 case vehicles and 588 control vehicles completed a structured interview. Main outcome measure: Hospitalisation or death of a vehicle occupant due to car crash injury. Results: Vehicles constructed before 1984 had significantly greater chance of being involved in an injury crash than those constructed after 1994 (odds ratio 2.88, 95% confidence interval (CI) 1.20 to 6.91), after adjustment for potential confounders. There was also a trend for increasing crash risk with each one year increase in vehicle age after adjustment for potential confounders (odds ratio 1.05, 95% CI 0.99 to 1.11; p = 0.09). Conclusion: This study quantifies the increased risk of car crash injury associated with older vehicle year and confirms this as an important public health issue. PMID:14693899
Vehicle year and the risk of car crash injury.
Blows, S; Ivers, R Q; Woodward, M; Connor, J; Ameratunga, S; Norton, R
2003-12-01
To quantify the association between vehicle age and risk of car crash injury. Data from a population based case-control study conducted in the Auckland region in 1998/99 was used to examine the adjusted risk of car crash injury or death due to vehicle age, after controlling for a range of known confounders. Cases were all cars involved in crashes in which at least one occupant was hospitalized or killed anywhere in the Auckland region, and controls were randomly selected cars on Auckland roads. The drivers of the 571 case vehicles and 588 control vehicles completed a structured interview. Hospitalisation or death of a vehicle occupant due to car crash injury. Vehicles constructed before 1984 had significantly greater chance of being involved in an injury crash than those constructed after 1994 (odds ratio 2.88, 95% confidence interval (CI) 1.20 to 6.91), after adjustment for potential confounders. There was also a trend for increasing crash risk with each one year increase in vehicle age after adjustment for potential confounders (odds ratio 1.05, 95% CI 0.99 to 1.11; p = 0.09). This study quantifies the increased risk of car crash injury associated with older vehicle year and confirms this as an important public health issue.
DOT National Transportation Integrated Search
2004-09-01
The following case study provides an in-depth view of the deployment of Commercial Vehicle Information Systems and Networks (CVISN) Electronic Credentialing in Washington State. It describes successful practices and lessons learned in operations and ...
Investigating methods for determining mismatch in near side vehicle impacts - biomed 2009.
Loftis, Kathryn; Martin, R Shayn; Meredith, J Wayne; Stitzel, Joel
2009-01-01
This study investigates vehicle mismatch in severe side-impact motor vehicle collisions. Research conducted by the Insurance Institute for Highway Safety has determined that vehicle mismatch often leads to very severe injuries for occupants in the struck vehicle, because the larger striking vehicle does not engage the lower sill upon impact, resulting in severe intrusions into the occupant compartment. Previous studies have analyzed mismatched collisions according to vehicle type, not by the difference in vehicle height and weight. It is hypothesized that the combination of a heavier striking vehicle at a taller height results in more intrusion for the struck vehicle and severe injury for the near side occupant. By analyzing Crash Injury Research and Engineering Network (CIREN) data and occupant injury severity, it is possible to study intrusion and injuries that occur due to vehicle mismatch. CIREN enrolls seriously injured occupants involved in motor vehicle crashes (MVC) across the United States. From the Toyota-Wake Forest University CIREN center, 23 near side impact cases involving two vehicles were recorded. Only 3 of these seriously injured occupant cases were not considered mismatched according to vehicle curb weight, and only 2 were not considered vehicle mismatched according to height differences. The mismatched CIREN cases had an average difference in vehicle curb weight of 737.0 kg (standard deviation of 646.8) and an average difference in vehicle height of 16.38 cm (standard deviation of 7.186). There were 13 occupants with rib fractures, 12 occupants with pelvic fractures, 9 occupants with pulmonary contusion, and 5 occupants with head injuries, among other multiple injuries. The average Injury Severity Score (ISS) for these occupants was 27, with a standard deviation of 16. The most serious injuries resulted in an Abbreviated Injury Scale (AIS) of 5, which included 3 occupants. Each of these AIS 5 injuries were to different body regions on different occupants. By analyzing the vehicle information and occupant injuries, it was found that the vehicle mismatch problem involves differences in vehicle weights and heights and also results in severe injuries to multiple body regions for the near side occupant involved. There was a low correlation of vehicle height difference to occupant ISS.
Pedrol, M T; Tolosana, M; Soler, M T; Taló, M; Godoy, P
2013-12-01
The objective of the study was to estimate the level of exposure of children under the age of 18 to second-hand smoke (SHS) inside motor vehicles. A prevalence study was conducted on the exposure of children under the age of 18 to SHS in motor vehicles in Lleida (Spain). The population was the users of private motor vehicles. The sample was random, and the data were collected by direct observation. The study variables were: the age and sex of the driver, whether the driver was smoking, and the presence of an exposed passenger under the age of 18. A total of 1600 vehicles were observed, 134 of which (8.4%) were carrying a child. In 8 of these 134 vehicles (6%; 95% CI: 2.5-11.0) a child was exposed to SHS. In all these cases, the driver was a male (P=0.02), and in 75% of cases he was over 40 years old. The rate of child exposure to SHS is very high. There is, therefore, a case for organising campaigns to prevent smoking tobacco inside motor vehicles in the presence of children in Spain. Copyright © 2012 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.
Hovering Dual-Spin Vehicle Groundwork for Bias Momentum Sizing Validation Experiment
NASA Technical Reports Server (NTRS)
Rothhaar, Paul M.; Moerder, Daniel D.; Lim, Kyong B.
2008-01-01
Angular bias momentum offers significant stability augmentation for hovering flight vehicles. The reliance of the vehicle on thrust vectoring for agility and disturbance rejection is greatly reduced with significant levels of stored angular momentum in the system. A methodical procedure for bias momentum sizing has been developed in previous studies. This current study provides groundwork for experimental validation of that method using an experimental vehicle called the Dual-Spin Test Device, a thrust-levitated platform. Using measured data the vehicle's thrust vectoring units are modeled and a gust environment is designed and characterized. Control design is discussed. Preliminary experimental results of the vehicle constrained to three rotational degrees of freedom are compared to simulation for a case containing no bias momentum to validate the simulation. A simulation of a bias momentum dominant case is presented.
DOT National Transportation Integrated Search
1997-10-01
The FHWA has commissioned the Commercial Vehicle Fleet Management and Information Systems study to determine if there are fleet management needs that the public sector can address through the development of ITS for commercial vehicle operations. As p...
Zhao, Peibo; Lee, Chris
2018-04-01
This study analyzes rear-end collision risk of cars and heavy vehicles on freeways using a surrogate safety measure. The crash potential index (CPI) was modified to reflect driver's reaction time and estimated by types of lead and following vehicles (car or heavy vehicle). CPIs were estimated using the individual vehicle trajectory data from a segment of the US-101 freeway in Los Angeles, U.S.A. It was found that the CPI was generally higher for the following heavy vehicle than the following car due to heavy vehicle's lower braking capability. This study also validates the CPI using the simulated traffic data which replicate the observed traffic conditions a few minutes before the crash time upstream and downstream of the crash locations. The observed data were obtained from crash records and loop detectors on a section of the Gardiner Expressway in Toronto, Canada. The result shows that the values of CPI were consistently higher during the traffic conditions immediately before the crash time (crash case) than the normal traffic conditions (non-crash case). This demonstrates that the CPI can be used to capture rear-end collision risk during car-following maneuver on freeways. The result also shows that rear-end collision risk is lower for heavy vehicles than cars in the crash case due to their shorter reaction time and lower speed when spacing is shorter. Thus, it is important to reflect the differences in driver behavior and vehicle performance characteristics between cars and heavy vehicles in estimating surrogate safety measures. Lastly, it was found that the CPI-based crash prediction model can correctly identify the crash and non-crash cases at higher accuracy than the other crash prediction models based on detectors. Copyright © 2018 Elsevier Ltd. All rights reserved.
Connected vehicle impacts on transportation planning : technical memorandum #5 : case studies.
DOT National Transportation Integrated Search
2015-12-01
The principal objective of this project, Connected Vehicle Impacts on Transportation Planning, is to comprehensively assess how connected vehicles should be considered across the range of transportation planning processes and products developed...
DOT National Transportation Integrated Search
2017-03-01
In TxDOT project 0-6817, Review and Evaluation of Current Gross Vehicle Weights and Axle : Load Limits, the project team reviewed the estimated costs imposed by use of overweight (OW) : vehicles and ways to allocate costs to different vehicle classes...
Crosswalk markings and the risk of pedestrian-motor vehicle collisions in older pedestrians.
Koepsell, Thomas; McCloskey, Lon; Wolf, Marsha; Moudon, Anne Vernez; Buchner, David; Kraus, Jess; Patterson, Matthew
2002-11-06
Motor vehicles struck and killed 4739 pedestrians in the United States in the year 2000. Older pedestrians are at especially high risk. To determine whether crosswalk markings at urban intersections influence the risk of injury to older pedestrians. Case-control study in which the units of study were crossing locations. Six cities in Washington and California, with case accrual from February 1995 through January 1999. A total of 282 case sites were street-crossing locations at an intersection where a pedestrian aged 65 years or older had been struck by a motor vehicle while crossing the street; 564 control sites were other nearby crossings that were matched to case sites based on street classification. Trained observers recorded environmental characteristics, vehicular traffic flow and speed, and pedestrian use at each site on the same day of the week and time of day as when the case event had occurred. Risk of pedestrian-motor vehicle collision involving an older pedestrian. After adjusting for pedestrian flow, vehicle flow, crossing length, and signalization, risk of a pedestrian-motor vehicle collision was 2.1-fold greater (95% confidence interval, 1.1-4.0) at sites with a marked crosswalk. Almost all of the excess risk was due to 3.6-fold (95% confidence interval, 1.7-7.9) higher risk associated with marked crosswalks at sites with no traffic signal or stop sign. Crosswalk markings appear associated with increased risk of pedestrian-motor vehicle collision to older pedestrians at sites where no signal or stop sign is present to halt traffic.
Case Study – Idling Reduction Technologies for Emergency Service Vehicles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laughlin, Michael; Owens, Russell J.
2016-01-01
This case study explores the use of idle reduction technologies (IRTs) on emergency service vehicles in police, fire, and ambulance applications. Various commercially available IRT systems and approaches can decrease, or ultimately eliminate, engine idling. Fleets will thus save money on fuel, and will also decrease their criteria pollutant emissions, greenhouse gas emissions, and noise.
Storvik, Steven G; Campbell, Julius Q; Wheeler, Jeffrey B
2017-06-01
Rates of death because of asphyxia in motor vehicle crashes have been previously estimated using county and statewide data sets, but national estimates have not been reported. The literature regarding asphyxia in motor vehicle crashes primarily involves discussions about clinical findings, and crash-related variables have been sparsely reported. The current study calculated a nationwide fatality rate for asphyxia in motor vehicle crashes of 1.4%. Seventeen case studies of asphyxia were also reported providing crash-, vehicle-, and occupant-related variables. These included type of accident, crash severity, seat belt use, containment status, extent of occupant compartment intrusion, height, weight, and injury pattern. The data presented can be used to better understand the injury mechanism, identify risk factors, develop possible protective countermeasures, and create situational awareness for emergency responders and investigators.
Toddler run-overs--a persistent problem.
Byard, Roger W; Jensen, Lisbeth L
2009-05-01
Trauma accounts for a high percentage of unexpected deaths in toddlers and young children, mostly due to vehicle accidents, drowning and fires. Given recent efforts to publicise the dangers of toddler run-overs a study was undertaken to determine how significant this problem remains in South Australia. Review of coronial files over 7 years from 2000 to 2006 revealed 50 cases of sudden and unexpected death in children aged between 1 and 3 years of which 12 of 28 accidents involved motor vehicles (6 run-overs and 6 passengers). The 6 children who were killed by vehicle run-overs were aged from 12 months to 22 months (ave=16.8 months) with a male to female ratio of 1:1. Four deaths occurred with reversing vehicles in home driveways and one at a community centre. The remaining death involved a child being run over at the beach by a forward moving vehicle. Vehicles included sedans in four cases and a four-wheel drive in one case (one vehicle was not described), and were driven by the victim's parent in four cases, a friend of the family in one, and an unrelated person in the final case. Deaths were all due to blunt cranial trauma. Despite initiatives to prevent these deaths, toddler run-overs in South Australia approximate the number of sudden deaths due to homicides, drownings and natural diseases, respectively, for the same age group; deaths are also occurring in places other than home driveways, and sedans were more often involved than four-wheel drive vehicles.
Potential benefits of underride guards in large truck side crashes.
Brumbelow, Matthew L
2012-01-01
To evaluate the maximum potential for side underride guards (SUGs) to reduce passenger vehicle occupant fatalities and injuries in crashes with large trucks in the United States. Examination of the Large Truck Crash Causation Study (LTCCS) identified 206 crash events involving a passenger vehicle impact with the side of a large truck. Each case was evaluated to determine whether the most severe injury sustained by a passenger vehicle occupant was a result of the impact with the side of the truck and whether an SUG could have reduced the injury severity. Data from the 2006-2008 Fatality Analysis Reporting System (FARS) and Trucks Involved in Fatal Accidents (TIFA) survey were used to compare the types of trucks involved in all fatal side impacts with passenger vehicles with the truck types in the LTCCS cases that were studied. FARS and TIFA data also were used to estimate the total annual number of passenger vehicle occupants killed in truck side impacts. In 143 of the 206 cases, the truck side impact produced the most severe injury sustained by a passenger vehicle occupant. In the other cases, no passenger vehicle occupant was injured or the most severe injury was due to an event preceding or following the truck side impact. Forty-nine of these occupants sustained injuries coded as level 3 or higher on the abbreviated injury scale (AIS) or were killed. SUGs could have reduced injury severity in 76 of the 143 cases, including 38 of the 49 cases with an AIS ≥ 3 coded injury or fatality. Semi-trailers were the most common type of impacted truck unit, both overall and when considering only cases where an SUG could have mitigated injury severity. Crashes where the front of the passenger vehicle struck the side of the semi-trailer perpendicularly or obliquely from the oncoming direction were less common overall than side-to-side and oblique/same direction crashes but more often produced an AIS ≥ 3 injury or fatality. The distribution of truck types in the LTCCS sample was similar to that in the FARS and TIFA data. Overall, around 1600 passenger vehicle occupants were killed in 2-vehicle truck side impact crashes during 2006-2008, or 22 percent of all passenger vehicle occupants who died in 2-vehicle crashes with large trucks. Structural incompatibility was a common factor in LTCCS crashes between passenger vehicles and the sides of large trucks. SUGs could have reduced injury risk in around three fourths of the crashes that produced an AIS ≥ 3 injury or fatality. Most of these crashes involved semi-trailers. However, the necessary strength and location of these SUGs present technical challenges that need to be addressed.
NASA Astrophysics Data System (ADS)
Pelzer, Dominik; Ciechanowicz, David; Aydt, Heiko; Knoll, Alois
2014-06-01
Employing electric vehicles as short-term energy storage could improve power system stability and at the same time create a new income source for vehicle owners. In this paper, the economic viability of this concept referred to as Vehicle-to-Grid is investigated. For this purpose, a price-responsive charging and dispatching strategy built upon temporally resolved electricity market data is presented. This concept allows vehicle owners to maximize returns by restricting market participation to profitable time periods. As a case study, this strategy is then applied using the example of Singapore. It is shown that an annual loss of S 1000 resulting from a non-price-responsive strategy as employed in previous works can be turned into a S 130 profit by applying the price-responsive approach. In addition to this scenario, realistic mobility patterns which restrict the temporal availability of vehicles are considered. In this case, profits in the range of S 21-S 121 are achievable. Returns in this order of magnitude are not expected to make Vehicle-to-Grid a viable business case, sensitivity analyses, however, show that improved technical parameters could increase profitability. It is further assumed that employing the price-responsive strategy to other national markets may yield significantly greater returns.
Low-speed vehicle run over fatalities in Australian children aged 0-5 years.
Anthikkat, Anne Paul; Page, Andrew; Barker, Ruth
2013-05-01
The study aims to investigate environmental, socio-demographic and other antecedent risk factors associated with low-speed vehicle run over (LSVRO) mortality in Australian children aged 0-5 years. This is a population-based retrospective case series study of Australian LSVRO mortality, July 2000-December 2010. Mortality and corresponding population data were stratified by sex and period to examine trends in incidence rates over the study period. Proportional mortality was also investigated by sex, age, period, area, location of injury, mechanism and other antecedent factors identified from textual coronial information. There were 82 fatal LSVRO cases over the 11-year study period. The annual incidence was low (less than 1 per 100,000) and declined over the study period. More than three-quarters of incidents occurred in non-traffic settings, in particular residential driveways. The most common vehicle involved was a four-wheel drive or utility with vehicles most likely to be reversing or leaving at the time of the incident. More than three-quarters of cases were aged 36 months or less. A higher proportion of LSVRO fatalities occurred in lower socio-economic status areas compared with higher socio-economic status areas. Where the vehicle was actively being driven (77 cases), the driver was known to the child in three-quarters of cases, most commonly the father (32%). The study provides a detailed analysis of mortality due to LSVRO incidents in Australia and highlights a number of modifiable antecedent factors. Precedents for the identification and reporting of LSVRO incidents as well as prevention strategies are discussed. © 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians).
Rodrigues, Ezequiel; Faria, Paula; Santos, Agostinho; Fraga, Sílvia
2016-04-01
The objective of this study was to investigate the terminal ballistics of police shootings in which the bullets went through any motor vehicle structure before fatally wounding the occupants. 6 cases that occurred in Porto district between 1998 and 2013 were studied. The firearms used were 7.65 mm (n = 1) or 9 mm (n = 3) calibre semi-automatic pistols and 9 mm calibre submachine guns (n = 2); the bullets were full metal jacket type. The metal jacket of the collected projectiles was totally or partially destroyed in 3 cases. It exhibited a deformed structure in all cases. The trajectories of the bullets in the vehicles were always more or less linear, even when initial impact was at an oblique angle. The entry holes in the victims' bodies were larger or much larger in size than the calibre of the bullets. They were located, with the exception of one of the cases, in the left half of the body. The trajectories in the victims' bodies were from front to back, in one case, and from back to front in all others. Exit wounds were only found in two cases. Death occurred immediately after the victim was shot only in one case, despite a vital structure has been hit in all cases. The cases studied support the idea that the use of firearms against vehicles with the sole intention of immobilisation entails uncontrollable danger to the lives of the occupants, and especially when done by police forces not specifically trained for that purpose. Therefore, such use of firearms should be avoided. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Application of travel time information for traffic management.
DOT National Transportation Integrated Search
2012-03-01
This report summarizes findings and implementations of probe vehicle data collection based on Bluetooth MAC address matching : technology. Probe vehicle travel time data are studied in the following field deployment case studies: analysis of traffic ...
Wind to Hydrogen in California: Case Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Antonia, O.; Saur, G.
2012-08-01
This analysis presents a case study in California for a large scale, standalone wind electrolysis site. This is a techno-economic analysis of the 40,000 kg/day renewable production of hydrogen and subsequent delivery by truck to a fueling station in the Los Angeles area. This quantity of hydrogen represents about 1% vehicle market penetration for a city such as Los Angeles (assuming 0.62 kg/day/vehicle and 0.69 vehicles/person) [8]. A wind site near the Mojave Desert was selected for proximity to the LA area where hydrogen refueling stations are already built.
Automobile exhaust as a means of suicide: an experimental study with a proposed model.
Morgen, C; Schramm, J; Kofoed, P; Steensberg, J; Theilade, P
1998-07-01
Experiments were conducted to investigate the concentration of carbon monoxide (CO) in a car cabin under suicide attempts with different vehicles and different start situations, and a mathematical model describing the concentration of CO in the cabin was constructed. Three cars were set up to donate the exhaust. The first vehicle didn't have any catalyst, the second one was equipped with a malfunctioning three-way catalyst, and the third car was equipped with a well-functioning three-way catalyst. The three different starting situations were cold, tepid and warm engine start, respectively. Measurements of the CO concentrations were made in both the cabin and in the exhaust pipe. Lethal concentrations were measured in the cabin using all three vehicles as the donor car, including the vehicle with the well-functioning catalyst. The model results in most cases gave a good prediction of the CO concentration in the cabin. Four case studies of cars used for suicides were described. In each case measurements of CO were made in both the cabin and the exhaust under different starting conditions, and the mathematical model was tested on these cases. In most cases the model predictions were good.
Seal Technology for Hypersonic Vehicle and Propulsion: An Overview
NASA Technical Reports Server (NTRS)
Steinetz, Bruce M.
2008-01-01
Hypersonic vehicles and propulsion systems pose an extraordinary challenge for structures and materials. Airframes and engines require lightweight, high-temperature materials and structural configurations that can withstand the extreme environment of hypersonic flight. Some of the challenges posed include very high temperatures, heating of the whole vehicle, steady-state and transient localized heating from shock waves, high aerodynamic loads, high fluctuating pressure loads, potential for severe flutter, vibration, and acoustic loads and erosion. Correspondingly high temperature seals are required to meet these aggressive requirements. This presentation reviews relevant seal technology for both heritage (e.g. Space Shuttle, X-15, and X-38) vehicles and presents several seal case studies aimed at providing lessons learned for future hypersonic vehicle seal development. This presentation also reviews seal technology developed for the National Aerospace Plane propulsion systems and presents several seal case studies aimed at providing lessons learned for future hypersonic propulsion seal development.
Changes in the Severity and Injury Sources of Thoracic Aorta Injuries due to Vehicular Crashes.
Ryb, Gabriel; Dischinger, Patricia; Kerns, Timothy; Burch, Cynthia; Rabin, Joseph; Ho, Shiu
Research using the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) suggested a decreased adjusted risk of thoracic aorta injuries (TAI) for newer vehicles during near-side crashes and an increased adjusted TAI risk during frontal crashes. This study attempted to explore possible explanations of these findings. Adult front seat occupants in the Crash Injury Research and Engineering Network (CIREN) database through June 2012 were studied. TAI cases were compared with remaining cases in relation to crash and vehicular characteristics. TAI cases of later crash year (CY) (2004-2012) were compared to those in earlier CY (1996-2003) in relation to TAI severity (minor, moderate, severe and non-survivable). TAI cases in newer model year (MY) vehicles (1999-2012) were compared to those in older vehicles (1988-98) in relation to injury source (steering wheel, front, left, seat belt, air bag and other or unknown). Analysis was stratified by direction of impact (frontal and near-side) and the use of restraints. The similar TAI severity of earlier and later CY among frontal crashes suggests that the observed changes in the adjusted odds of injury seen in NASS-CDS are not due to an increase in injury detection. The decrease in TAI severity among newer vehicles in near-side crashes of later CY is consistent with a beneficial effect of crashworthiness improvements for this crash configuration. A shift of injury source in frontal crashes from the steering wheel in older vehicles to "front of vehicle structures", "seat belts" and "unknown and other" in newer vehicles should suggest potential sites for crashworthiness improvements.
Database architecture and query structures for probe data processing.
DOT National Transportation Integrated Search
2012-03-01
This report summarizes findings and implementations of probe vehicle data collection based on Bluetooth MAC address matching technology. Probe vehicle travel time data are studied in the following field deployment case studies: analysis of traffic ch...
Effects of changing HOV lane occupancy requirements : El Monte busway case study
DOT National Transportation Integrated Search
2002-06-01
In 1999, the California Legislature passed Senate Bill 63, which lowered the vehicle-occupancy requirement on the El Monte Busway on the San Bernardino (I-10) Freeway from three persons per vehicle (3+) to two persons per vehicle (2+) full time. The ...
Executive report : effects of changing HOV lane occupancy requirements : El Monte busway case study.
DOT National Transportation Integrated Search
2002-09-01
In 1999, the California Legislature passed Senate Bill 63, which lowered the vehicle-occupancy requirement on the El Monte Busway on the San Bernardino (I-10) Freeway from three persons per vehicle (3+) to two persons per vehicle (2+) full time. The ...
Patel, J.N.; Tan, A.; Frew, Q.; Dziewulski, P.
2016-01-01
Summary A preventable subgroup of burn injuries is scalds sustained from motor vehicle radiators. This study was to determine changes in trends in epidemiology of such injuries and to discuss whether current and other prevention efforts proposed previously require reinforcement. We conducted a retrospective study (February 2007-August 2015) of all motor vehicle-related burn referrals to our regional burns service. 68 cases of motor vehicle radiator burns were identified. Male to female ratio was 65:3. Mean age was 35.1 (range = 9-71). Most cases occurred in the summer months (22/68 = 32.4%). 65 cases (95.6%) involved car radiators. 66% of injuries resulted from actively removing the pressure cap of an overheated radiator in the motor vehicle. Mean total burn surface area (%TBSA) was 2.1% (range = 0.5- 11%). The depths of burn injuries were mostly superficial partial thickness. Face, chest and upper limbs were the most common sites of injury. Mean healing time was 14.2 days (range = 4-60). Following the introduction of safety measures by vehicle manufacturers, motor vehicle radiator burns in this era are mostly minor injuries and can be potentially managed conservatively as an outpatient. This contrasts with findings from previous studies over a decade ago of larger, more significant injuries requiring admission and surgery. Whilst manufacturers have installed safety measures into the design of radiator caps, our findings suggest that re-educating the public to allow a period of cooling prior to opening caps should be reinforced. PMID:28289357
Patel, J N; Tan, A; Frew, Q; Dziewulski, P
2016-12-31
A preventable subgroup of burn injuries is scalds sustained from motor vehicle radiators. This study was to determine changes in trends in epidemiology of such injuries and to discuss whether current and other prevention efforts proposed previously require reinforcement. We conducted a retrospective study (February 2007-August 2015) of all motor vehicle-related burn referrals to our regional burns service. 68 cases of motor vehicle radiator burns were identified. Male to female ratio was 65:3. Mean age was 35.1 (range = 9-71). Most cases occurred in the summer months (22/68 = 32.4%). 65 cases (95.6%) involved car radiators. 66% of injuries resulted from actively removing the pressure cap of an overheated radiator in the motor vehicle. Mean total burn surface area (%TBSA) was 2.1% (range = 0.5- 11%). The depths of burn injuries were mostly superficial partial thickness. Face, chest and upper limbs were the most common sites of injury. Mean healing time was 14.2 days (range = 4-60). Following the introduction of safety measures by vehicle manufacturers, motor vehicle radiator burns in this era are mostly minor injuries and can be potentially managed conservatively as an outpatient. This contrasts with findings from previous studies over a decade ago of larger, more significant injuries requiring admission and surgery. Whilst manufacturers have installed safety measures into the design of radiator caps, our findings suggest that re-educating the public to allow a period of cooling prior to opening caps should be reinforced.
Case series analysis of hindfoot injuries sustained by drivers in frontal motor vehicle crashes.
Ye, Xin; Funk, James; Forbes, Aaron; Hurwitz, Shepard; Shaw, Greg; Crandall, Jeff; Freeth, Rob; Michetti, Chris; Rudd, Rodney; Scarboro, Mark
2015-09-01
Improvements to vehicle frontal crashworthiness have led to reductions in toe pan and instrument panel intrusions as well as leg, foot, and ankle loadings in standardized crash tests. Current field data, however, suggests the proportion of foot and ankle injuries sustained by drivers in frontal crashes has not decreased over the past two decades. To explain the inconsistency between crash tests results and real world lower limb injury prevalence, this study investigated the injury causation scenario for the specific hind-foot injury patterns observed in frontal vehicle crashes. Thirty-four cases with leg, foot, and ankle injuries were selected from the Crash Injury Research and Engineering Network (CIREN) database. Talus fractures were present in 20 cases, representing the most frequent hind-foot skeletal injuries observed among the reviewed cases. While axial compression was the predominant loading mechanism causing 18 injuries, 11 injured ankles involved inversion or eversion motion, and 5 involved dorsiflexion as the injury mechanism. Injured ankles of drivers were more biased towards the right aspect with foot pedals contributing to injuries in 13 of the 34 cases. Combined, the results suggest that despite recent advancement of vehicle performance in crash tests, efforts to reduce axial forces sustained in lower extremity should be prioritized. The analysis of injury mechanisms in this study could aid in crash reconstructions and the development of safety systems for vehicles. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Changes in the Severity and Injury Sources of Thoracic Aorta Injuries due to Vehicular Crashes
Ryb, Gabriel; Dischinger, Patricia; Kerns, Timothy; Burch, Cynthia; Rabin, Joseph; Ho, Shiu
2013-01-01
Research using the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) suggested a decreased adjusted risk of thoracic aorta injuries (TAI) for newer vehicles during near-side crashes and an increased adjusted TAI risk during frontal crashes. This study attempted to explore possible explanations of these findings. Adult front seat occupants in the Crash Injury Research and Engineering Network (CIREN) database through June 2012 were studied. TAI cases were compared with remaining cases in relation to crash and vehicular characteristics. TAI cases of later crash year (CY) (2004–2012) were compared to those in earlier CY (1996–2003) in relation to TAI severity (minor, moderate, severe and non-survivable). TAI cases in newer model year (MY) vehicles (1999–2012) were compared to those in older vehicles (1988–98) in relation to injury source (steering wheel, front, left, seat belt, air bag and other or unknown). Analysis was stratified by direction of impact (frontal and near-side) and the use of restraints. The similar TAI severity of earlier and later CY among frontal crashes suggests that the observed changes in the adjusted odds of injury seen in NASS-CDS are not due to an increase in injury detection. The decrease in TAI severity among newer vehicles in near-side crashes of later CY is consistent with a beneficial effect of crashworthiness improvements for this crash configuration. A shift of injury source in frontal crashes from the steering wheel in older vehicles to “front of vehicle structures”, “seat belts” and “unknown and other” in newer vehicles should suggest potential sites for crashworthiness improvements. PMID:24406956
DallʼOglio, Federica; Luca, Maria; Barresi, Sebastiano; Micali, Giuseppe
Contact immunotherapy with squaric acid dibutylester (SADBE) for cutaneous warts has been reported to be effective, although no controlled studies are available so far. The aim of this study was to evaluate the efficacy of SADBE on cutaneous warts by a randomized, double-blind, vehicle-controlled, clinical trial. Thirty-six patients were randomly assigned to SADBE (18 cases) or vehicle (18 cases) group. At 8 weeks, subjects were clinically evaluated for number/size reduction rate and for Investigator Global Assessment. Those who showed improvement extended therapy up to 40 weeks, whereas those who showed unresponsiveness were either switched to SADBE application for up to 48 weeks (if in the vehicle group) or withdrawn from the study (if under SADBE). At 8 weeks, a significant reduction in wart number (P = 0.020) and size (P = 0.010) in the SADBE group, with clearing rates of 41.2% versus 12.5% in the SADBE and vehicle groups, respectively, was observed. Nine remaining SADBE responders who underwent treatment extension up to 40 weeks achieved clearing versus 2 patients of the vehicle group who remained unresponsive. Clearing was obtained in 81.8% of patients who underwent previous ineffective vehicle treatment and had been switched to SADBE. Squaric acid dibutylester is an effective therapeutic option and is significantly more effective than vehicle.
Connected Vehicle Infrastructure : Deployment and Funding Overview
DOT National Transportation Integrated Search
2018-01-01
This report reviews existing and proposed legislation relevant to connected vehicle infrastructure (CVI) implementation, identifies existing funding mechanisms for CVI implementation, reviews CVI pilot programs and case studies, and provides an overv...
Virtual Learning Communities as a Vehicle for Workforce Development: A Case Study
ERIC Educational Resources Information Center
Allan, Barbara; Lewis, Dina
2006-01-01
Purpose: The purpose of this paper is to explore the benefits and challenges of using a virtual learning community (VLC) as a vehicle for workforce development. This paper argues that VLCs provide a flexible vehicle for workforce development. However, workplace realities may lead to unexpected challenges for participants wanting exploit the…
Nearest greedy for solving the waste collection vehicle routing problem: A case study
NASA Astrophysics Data System (ADS)
Mat, Nur Azriati; Benjamin, Aida Mauziah; Abdul-Rahman, Syariza; Wibowo, Antoni
2017-11-01
This paper presents a real case study pertaining to an issue related to waste collection in the northern part of Malaysia by using a constructive heuristic algorithm known as the Nearest Greedy (NG) technique. This technique has been widely used to devise initial solutions for issues concerning vehicle routing. Basically, the waste collection cycle involves the following steps: i) each vehicle starts from a depot, ii) visits a number of customers to collect waste, iii) unloads waste at the disposal site, and lastly, iv) returns to the depot. Moreover, the sample data set used in this paper consisted of six areas, where each area involved up to 103 customers. In this paper, the NG technique was employed to construct an initial route for each area. The solution proposed from the technique was compared with the present vehicle routes implemented by a waste collection company within the city. The comparison results portrayed that NG offered better vehicle routes with a 11.07% reduction of the total distance traveled, in comparison to the present vehicle routes.
Alternative Fuels Data Center: Hybrid and Plug-In Electric Vehicle
components. In some cases, conversions can affect the vehicle's factory warranty. HEV conversions require which point the vehicle acts like an HEV. In some cases, conversions can affect the vehicle's factory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephens, T. S.; Taylor, C. H.; Moore, J. S.
Under a diverse set of programs, the Vehicle Technologies and Fuel Cell Technologies offices of DOE’s Office of Energy Efficiency and Renewable Energy invest in research, development, demonstration, and deployment of advanced vehicle, hydrogen production, delivery and storage, and fuel cell technologies. This report estimates the benefits of successfully developing and deploying these technologies (a “Program Success” case) relative to a base case (the “No Program” case). The Program Success case represents the future with completely successful deployment of Vehicle Technologies Office (VTO) and Fuel Cell Technologies Office (FCTO) technologies. The No Program case represents a future in which theremore » is no contribution after FY 2016 by the VTO or FCTO to these technologies. The benefits of advanced vehicle, hydrogen production, delivery and storage, and fuel cell technologies were estimated on the basis of differences in fuel use, primary energy use, and greenhouse gas (GHG) emissions from light-, medium- and heavy-duty vehicles, including energy and emissions from fuel production, between the base case and the Program Success case. Improvements in fuel economy of various vehicle types, growth in the stock of fuel cell vehicles and other advanced technology vehicles, and decreased GHG intensity of hydrogen production and delivery in the Program Success case over the No Program case were projected to result in savings in petroleum use and GHG emissions. Benefits were disaggregated by individual program technology areas, which included the FCTO program and the VTO subprograms of batteries and electric drives; advanced combustion engines; fuels and lubricants; materials (for reduction in vehicle mass, or “lightweighting”); and, for medium- and heavy-duty vehicles, reduction in rolling and aerodynamic resistance. Projections for the Program Success case indicate that by 2035, the average fuel economy of on-road, light-duty vehicle stock could be 47% to 76% higher than in the No Program case. On-road medium- and heavy-duty vehicle stock could be as much as 39% higher. The resulting petroleum savings in 2035 were estimated to be as high as 3.1 million barrels per day, and reductions in GHG emissions were estimated to be as high as 500 million metric tons of CO2 equivalent per year. The benefits of continuing to invest government resources in advanced vehicle and fuel cell technologies would have significant economic value in the U.S. transportation sector and reduce its dependency on oil and its vulnerability to oil price shocks.« less
DIAGNOSTIC TOOL DEVELOPMENT AND APPLICATION THROUGH REGIONAL CASE STUDIES
Case studies are a useful vehicle for developing and testing conceptual models, classification systems, diagnostic tools and models, and stressor-response relationships. Furthermore, case studies focused on specific places or issues of interest to the Agency provide an excellent ...
Defining Special-Use Lanes: Case Studies and Guidelines
DOT National Transportation Integrated Search
2000-10-01
This research assesses the feasibility of high-occupancy vehicle (HOV)and high-occupancy vehicle/toll (HOT) facilities. In this report, current operational facilities are described and guidelines for the operation, design, agency involvement, and mon...
Herman, Josephine; Kafoa, Berlin; Wainiqolo, Iris; Robinson, Elizabeth; McCaig, Eddie; Connor, Jennie; Jackson, Rod; Ameratunga, Shanthi
2014-03-01
Published studies investigating the role of driver sleepiness in road crashes in low and middle-income countries have largely focused on heavy vehicles. We investigated the contribution of driver sleepiness to four-wheel motor vehicle crashes in Fiji, a middle-income Pacific Island country. The population-based case control study included 131 motor vehicles involved in crashes where at least one person died or was hospitalised (cases) and 752 motor vehicles identified in roadside surveys (controls). An interviewer-administered questionnaire completed by drivers or proxies collected information on potential risks for crashes including sleepiness while driving, and factors that may influence the quantity or quality of sleep. Following adjustment for confounders, there was an almost six-fold increase in the odds of injury-involved crashes for vehicles driven by people who were not fully alert or sleepy (OR 5.7, 95%CI: 2.7, 12.3), or those who reported less than 6 h of sleep during the previous 24 h (OR 5.9, 95%CI: 1.7, 20.9). The population attributable risk for crashes associated with driving while not fully alert or sleepy was 34%, and driving after less than 6 h sleep in the previous 24 h was 9%. Driving by people reporting symptoms suggestive of obstructive sleep apnoea was not significantly associated with crash risk. Driver sleepiness is an important contributor to injury-involved four-wheel motor vehicle crashes in Fiji, highlighting the need for evidence-based strategies to address this poorly characterised risk factor for car crashes in less resourced settings. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.
Injury pattern in lethal motorbikes-pedestrian collisions, in the area of Barcelona, Spain.
Rebollo-Soria, M Carmen; Arregui-Dalmases, Carlos; Sánchez-Molina, David; Velázquez-Ameijide, Juan; Galtés, Ignasi
2016-10-01
There are several studies about M1 type vehicle-pedestrian collision injury pattern, and based on them, there has been several changes in automobiles for pedestrian protection. However, the lack of sufficient studies about injury pattern in motorbikes-pedestrian collisions leads to a lack of optimization design of these vehicles. The objective of this research is to study the injury pattern of pedestrians involved in collisions with motorized two-wheeled vehicles. A retrospective descriptive study of pedestrian's deaths after collisions with motorcycles in an urban area, like Barcelona was performed. The cases were collected from the Forensic Pathology Service database of the Institute of Legal Medicine of Catalonia. The selected cases were categorized as pedestrian-motorcycle collision, between January 1st, 2005 and December 31st, 2014. Data were collected from the autopsy, medical, and police report. The collected information was then analyzed using Microsoft Excel statistical functions. Traumatic Brain Injury is the main cause of death in pedestrian hit by motorized two-wheeled vehicles (62.85%). The most frequent injury was the subarachnoid hemorrhage, in 71.4% of cases, followed by cerebral contusions and skull base fractures (65.7%). By contrast, pelvic fractures and tibia fractures only appeared in 28.6%. The study characterizes the injury pattern of pedestrians involved in a collision with motorized two-wheeled vehicles in an urban area, like Barcelona, which has been found to be different from other vehicle-pedestrian collisions, with a higher incidence of brain injuries and minor frequency of lower extremities fractures in pelvis, tibia and fibula. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Quantifying electric vehicle battery degradation from driving vs. vehicle-to-grid services
NASA Astrophysics Data System (ADS)
Wang, Dai; Coignard, Jonathan; Zeng, Teng; Zhang, Cong; Saxena, Samveg
2016-11-01
The risk of accelerated electric vehicle battery degradation is commonly cited as a concern inhibiting the implementation of vehicle-to-grid (V2G) technology. However, little quantitative evidence exists in prior literature to refute or substantiate these concerns for different grid services that vehicles may offer. In this paper, a methodology is proposed to quantify electric vehicle (EV) battery degradation from driving only vs. driving and several vehicle-grid services, based on a semi-empirical lithium-ion battery capacity fade model. A detailed EV battery pack thermal model and EV powertrain model are utilized to capture the time-varying battery temperature and working parameters including current, internal resistance and state-of-charge (SOC), while an EV is driving and offering various grid services. We use the proposed method to simulate the battery degradation impacts from multiple vehicle-grid services including peak load shaving, frequency regulation and net load shaping. The degradation impact of these grid services is compared against baseline cases for driving and uncontrolled charging only, for several different cases of vehicle itineraries, driving distances, and climate conditions. Over the lifetime of a vehicle, our results show that battery wear is indeed increased when vehicles offer V2G grid services. However, the increased wear from V2G is inconsequential compared with naturally occurring battery wear (i.e. from driving and calendar ageing) when V2G services are offered only on days of the greatest grid need (20 days/year in our study). In the case of frequency regulation and peak load shaving V2G grid services offered 2 hours each day, battery wear remains minimal even if this grid service is offered every day over the vehicle lifetime. Our results suggest that an attractive tradeoff exists where vehicles can offer grid services on the highest value days for the grid with minimal impact on vehicle battery life.
IVHS Institutional Issues and Case Studies, Analysis and Lessons Learned, Final Report
DOT National Transportation Integrated Search
1994-04-01
This 'Analysis and Lessons Learned' report contains observations, conclusions, and recommendations based on the performance of six case studies of Intelligent Vehicle-Highway Systems (IVHS) projects. Information to support the development of the case...
High occupancy vehicle project case studies : historical trends and project experiences
DOT National Transportation Integrated Search
1992-08-01
High-occupancy vehicle (HOV) facilities represent one approach being used in many metropolitan areas today to respond to increasing traffic congestion, declining mobility levels, air quality and environmental concerns, and limited resources. HOV faci...
TDM Case Studies and Commuter Testimonials
DOT National Transportation Integrated Search
1998-01-01
When the effects of Travel demand management (TDM) are quantified, it's usually : in terms of mode splits, vehicle miles traveled, average vehicle ridership, : pounds of pollutants saved, and so forth. But to fully appreciate the effect of : TDM stra...
Injury patterns and preventability in prehospital motor vehicle crash fatalities in Victoria.
Ryan, Matt; Stella, Julian; Chiu, Herman; Ragg, Michael
2004-08-01
To examine the pattern of anatomical injury in victims of motor vehicle crashes who die prior to reaching hospital. Cases were identified where death was an unexpected outcome. A retrospective review of autopsy case records including police reports, of all persons who died in motor vehicle crashes between 1 January 1998 and 31 December 1999 and underwent full autopsy at the Victorian Institute of Forensic Medicine (VIFM). Those cases where the victim died in the prehospital phase were examined. Abbreviate Injury Scores and Injury Severity Scores were calculated in each case. Bull's probit analysis was used to identify unexpected deaths. There were 352 motor road crash fatalities identified that underwent autopsy at the VIFM in the study period. Two hundred and six of these were prehospital deaths involving motor vehicles, which satisfied specified criteria. 82% (95% CI: 77.7-86.3%) of cases had Abbreviated Injury Scores of 5 (critical) or 6 (incompatible with life). 80.1% (95% CI: 75.7-84.5%) had an Injury Severity Score greater than 40. 36.9% (95% CI: 34.5-39.3%) of cases had the maximum Injury Severity score of 75. 88.8% (95% CI: 85-92.7%) of cases sustained a head injury and 83.9% (95% CI: 79.8-88.2%) a chest injury. Possibly preventable fatality was identified in 30 (14.6% 95% CI: 13.9-15.3%) cases. In motor vehicle crash fatalities, most victims who die before reaching hospital do so because of major injury, with the head and chest the commonest regions involved. A large proportion of these injuries could be considered unsurvivable regardless of treatment. Earlier intervention or retrieval of such patients is unlikely to influence outcome in the majority of cases.
Kelly, Jarod C; Sullivan, John L; Burnham, Andrew; Elgowainy, Amgad
2015-10-20
This study examines the vehicle-cycle and vehicle total life-cycle impacts of substituting lightweight materials into vehicles. We determine part-based greenhouse gas (GHG) emission ratios by collecting material substitution data and evaluating that alongside known mass-based GHG ratios (using and updating Argonne National Laboratory's GREET model) associated with material pair substitutions. Several vehicle parts are lightweighted via material substitution, using substitution ratios from a U.S. Department of Energy report, to determine GHG emissions. We then examine fuel-cycle GHG reductions from lightweighting. The fuel reduction value methodology is applied using FRV estimates of 0.15-0.25, and 0.25-0.5 L/(100km·100 kg), with and without powertrain adjustments, respectively. GHG breakeven values are derived for both driving distance and material substitution ratio. While material substitution can reduce vehicle weight, it often increases vehicle-cycle GHGs. It is likely that replacing steel (the dominant vehicle material) with wrought aluminum, carbon fiber reinforced plastic (CRFP), or magnesium will increase vehicle-cycle GHGs. However, lifetime fuel economy benefits often outweigh the vehicle-cycle, resulting in a net total life-cycle GHG benefit. This is the case for steel replaced by wrought aluminum in all assumed cases, and for CFRP and magnesium except for high substitution ratio and low FRV.
Kim, Taewung; Bose, Dipan; Foster, Jon; Bollapragada, Varun; Crandall, Jeff R; Clauser, Mark; Kerrigan, Jason R
2017-10-01
This study aimed to identify common patterns of pre-ballistic vehicle kinematics and roadway characteristics of real-world rollover crashes. Rollover crashes that were enrolled in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) between the years 2000 and 2010 were analyzed. A descriptive analysis was performed to understand the characteristics of the pre-ballistic phase. Also, a frequency based pattern analysis was performed using a selection of NASS-CDS variables describing the pre-ballistic vehicle kinematics and roadway characteristics to rank common pathways of rollover crashes. Most case vehicles departed the road due to a loss of control/traction (LOC) (61%). The road departure with LOC was found to be 13.4 times more likely to occur with slippery road conditions compared to dry conditions. The vehicle was typically laterally skidding with yawing prior to a rollover (66%). Most case vehicles tripped over (82%) mostly at roadside/median (69%). The tripping force was applied to the wheels/tires (82%) from the ground (79%). The combination of these six most frequent attributes resulted in the most common scenario, which accounted for 26% of the entire cases. Large proportion of road departure with LOC (61%) implies electronic stability control (ESC) systems being an effective countermeasure for preventing single-vehicle rollover crashes. Furthermore, the correlation between the road departure with LOC and the reduced friction limit suggests the necessity of the performance evaluation of ESC under compromised road surface condition. Copyright © 2017 Elsevier Ltd. All rights reserved.
Differential Rollover Risk in Vehicle-to-Traffic Barrier Collisions
Gabauer, Douglas J.; Gabler, Hampton C.
2009-01-01
In the roadside safety community, there has been debate over the influence of vehicle and barrier type on rollover rates in traffic barrier crashes. This study investigated rollover rates between sport utility vehicles (SUVs), pickup trucks, and cars in vehicle-traffic barrier crashes and has examined the effect of barrier type on rollover risk for concrete barrier and metal barrier impacts. The analysis included 955 barrier impact cases that were selected from 11-years of in-depth crash data available through the National Automotive Sampling System (NASS) / Crashworthiness Data System (CDS). In real world tow-away level longitudinal barrier collisions, the most important predictors of vehicle rollover were found to be vehicle type and whether the vehicle was tracking prior to barrier impact. Based on binary logistic regression, SUVs were found to have 8 times the risk of rollover as cars in barrier impacts. Although pickups were found to have an increased risk of rollover compared to cars, the risk was not as pronounced as that found for SUVs. This finding has direct implications for the full scale crash testing of longitudinal barriers as the testing procedures have been predicated on the assumption that the pickup truck provides a critical or worst case impact scenario. In towaway crashes, our study does not support the notion that concrete barriers have a higher risk of vehicle rollover than metal beam barriers. PMID:20184839
Electronic credentialing for commercial vehicle operations : a cross-cutting analysis
DOT National Transportation Integrated Search
1999-06-10
This case study presents an analysis of how Maryland, Virginia, and Kentucky have used the Commercial Vehicle Information Systems & Networks (CVISN) Architecture to develop state CVISN systems designs for electronic credentialing. Focus is on the CVI...
Burst fractures of the lumbar spine in frontal crashes.
Kaufman, Robert P; Ching, Randal P; Willis, Margaret M; Mack, Christopher D; Gross, Joel A; Bulger, Eileen M
2013-10-01
In the United States, major compression and burst type fractures (>20% height loss) of the lumbar spine occur as a result of motor vehicle crashes, despite the improvements in restraint technologies. Lumbar burst fractures typically require an axial compressive load and have been known to occur during a non-horizontal crash event that involve high vertical components of loading. Recently these fracture patterns have also been observed in pure horizontal frontal crashes. This study sought to examine the contributing factors that would induce an axial compressive force to the lumbar spine in frontal motor vehicle crashes. We searched the National Automotive Sampling System (NASS, 1993-2011) and Crash Injury Research and Engineering Network (CIREN, 1996-2012) databases to identify all patients with major compression lumbar spine (MCLS) fractures and then specifically examined those involved in frontal crashes. National trends were assessed based on weighted NASS estimates. Using a case-control study design, NASS and CIREN cases were utilized and a conditional logistic regression was performed to assess driver and vehicle characteristics. CIREN case studies and biomechanical data were used to illustrate the kinematics and define the mechanism of injury. During the study period 132 NASS cases involved major compression lumbar spine fractures for all crash directions. Nationally weighted, this accounted for 800 cases annually with 44% of these in horizontal frontal crashes. The proportion of frontal crashes resulting in MCLS fractures was 2.5 times greater in late model vehicles (since 2000) as compared to 1990s models. Belted occupants in frontal crashes had a 5 times greater odds of a MCLS fracture than those not belted, and an increase in age also greatly increased the odds. In CIREN, 19 cases were isolated as horizontal frontal crashes and 12 of these involved a major compression lumbar burst fracture primarily at L1. All were belted and almost all occurred in late model vehicles with belt pretensioners and buckets seats. Major compression burst fractures of the lumbar spine in frontal crashes were induced via a dynamic axial force transmitted to the pelvis/buttocks into the seat cushion/pan involving belted occupants in late model vehicles with increasing age as a significant factor. Copyright © 2013 Elsevier Ltd. All rights reserved.
Alternative Fuels Data Center: Biodiesel Fueling Stations
Case Studies California Ramps Up Biofuels Infrastructure Green Fueling Station Powers Fleets in Upstate New York New Hampshire Railway Makes Tracks With Biodiesel More Biodiesel Case Studies | All Case Studies Publications 2016 Vehicle Technologies Market Report Biodiesel Handling and Use Guide (Fifth
Integrated corridor management transit vehicle real-time data demonstration: Dallas case study
DOT National Transportation Integrated Search
2014-12-01
As part of the U.S. Department of Transportations Integrated Corridor Management (ICM) Initiative, Dallas Area Rapid Transit (DART) purchased new automatic passenger counter (APC) technology for its Red and Orange line light rail vehicles to provi...
A heterogeneous fleet vehicle routing model for solving the LPG distribution problem: A case study
NASA Astrophysics Data System (ADS)
Onut, S.; Kamber, M. R.; Altay, G.
2014-03-01
Vehicle Routing Problem (VRP) is an important management problem in the field of distribution and logistics. In VRPs, routes from a distribution point to geographically distributed points are designed with minimum cost and considering customer demands. All points should be visited only once and by one vehicle in one route. Total demand in one route should not exceed the capacity of the vehicle that assigned to that route. VRPs are varied due to real life constraints related to vehicle types, number of depots, transportation conditions and time periods, etc. Heterogeneous fleet vehicle routing problem is a kind of VRP that vehicles have different capacity and costs. There are two types of vehicles in our problem. In this study, it is used the real world data and obtained from a company that operates in LPG sector in Turkey. An optimization model is established for planning daily routes and assigned vehicles. The model is solved by GAMS and optimal solution is found in a reasonable time.
Alternative Fuels Data Center: Biodiesel Fueling Infrastructure Development
Biodiesel Fueling Station Locations by State More Biodiesel Data | All Maps & Data Case Studies Recycled Fuels Help Ensure America's National Parks Stay Green for Another Century More Biodiesel Case Studies | All Case Studies Publications 2016 Vehicle Technologies Market Report Biodiesel Handling and Use Guide
Songs from the Car Seat: Exploring the Early Childhood Music-Making Place of the Family Vehicle
ERIC Educational Resources Information Center
Koops, Lisa Huisman
2014-01-01
The purpose of this qualitative case study was to investigate the musical "place" of the family vehicle by describing the music making of nine young children, ages 10 months to 4.5 years, that occurred in vehicles over the course of 9 weeks during which the children were enrolled in a researcher-led early childhood music course. Research…
Advanced Vehicle Concepts and Implications for NextGen
NASA Technical Reports Server (NTRS)
Blake, Matt; Smith, Jim; Wright, Ken; Mediavilla Ricky; Kirby, Michelle; Pfaender, Holger; Clarke, John-Paul; Volovoi, Vitali; Dorbian, Christopher; Ashok, Akshay;
2010-01-01
This report presents the results of a major NASA study of advanced vehicle concepts and their implications for the Next Generation Air Transportation System (NextGen). Comprising the efforts of dozens of researchers at multiple institutions, the analyses presented here cover a broad range of topics including business-case development, vehicle design, avionics, procedure design, delay, safety, environmental impacts, and metrics. The study focuses on the following five new vehicle types: Cruise-efficient short takeoff and landing (CESTOL) vehicles Large commercial tiltrotor aircraft (LCTRs) Unmanned aircraft systems (UAS) Very light jets (VLJs) Supersonic transports (SST). The timeframe of the study spans the years 2025-2040, although some analyses are also presented for a 3X scenario that has roughly three times the number of flights as today. Full implementation of NextGen is assumed.
Systematic review of military motor vehicle crash-related injuries.
Krahl, Pamela L; Jankosky, Christopher J; Thomas, Richard J; Hooper, Tomoko I
2010-01-01
Motor vehicle crashes account for nearly one third of U.S. military fatalities annually. The objective of this review is to summarize the published evidence on injuries due specifically to military motor vehicle (MMV) crashes. A search of 18 electronic databases identified English language publications addressing MMV crash-related injuries between 1970 and 2006 that were available to the general public. Documents limited in distribution to military or government personnel were not evaluated. Relevant articles were categorized by study design. The search identified only 13 studies related specifically to MMV crashes. Most were case reports or case series (n=8); only one could be classified as an intervention study. Nine of the studies were based solely on data from service-specific military safety centers. Few studies exist on injuries resulting from crashes of military motor vehicles. Epidemiologic studies that assess injury rates, type, severity, and risk factors are needed, followed by studies to evaluate targeted interventions and prevention strategies. Interventions currently underway should be evaluated for effectiveness, and those proven effective in the civilian community, such as graduated driver licensing, should be considered for implementation and evaluation in military populations. Published by Elsevier Inc.
A Case Study of Dynamic Response Analysis and Safety Assessment for a Suspended Monorail System.
Bao, Yulong; Li, Yongle; Ding, Jiajie
2016-11-10
A suspended monorail transit system is a category of urban rail transit, which is effective in alleviating traffic pressure and injury prevention. Meanwhile, with the advantages of low cost and short construction time, suspended monorail transit systems show vast potential for future development. However, the suspended monorail has not been systematically studied in China, and there is a lack of relevant knowledge and analytical methods. To ensure the health and reliability of a suspended monorail transit system, the driving safety of vehicles and structure dynamic behaviors when vehicles are running on the bridge should be analyzed and evaluated. Based on the method of vehicle-bridge coupling vibration theory, the finite element method (FEM) software ANSYS and multi-body dynamics software SIMPACK are adopted respectively to establish the finite element model for bridge and the multi-body vehicle. A co-simulation method is employed to investigate the vehicle-bridge coupling vibration for the transit system. The traffic operation factors, including train formation, track irregularity and tire stiffness, are incorporated into the models separately to analyze the bridge and vehicle responses. The results show that the coupling of dynamic effects of the suspended monorail system between vehicle and bridge are significant in the case studied, and it is strongly suggested to take necessary measures for vibration suppression. The simulation of track irregularity is a critical factor for its vibration safety, and the track irregularity of A-level road roughness negatively influences the system vibration safety.
A Case Study of Dynamic Response Analysis and Safety Assessment for a Suspended Monorail System
Bao, Yulong; Li, Yongle; Ding, Jiajie
2016-01-01
A suspended monorail transit system is a category of urban rail transit, which is effective in alleviating traffic pressure and injury prevention. Meanwhile, with the advantages of low cost and short construction time, suspended monorail transit systems show vast potential for future development. However, the suspended monorail has not been systematically studied in China, and there is a lack of relevant knowledge and analytical methods. To ensure the health and reliability of a suspended monorail transit system, the driving safety of vehicles and structure dynamic behaviors when vehicles are running on the bridge should be analyzed and evaluated. Based on the method of vehicle-bridge coupling vibration theory, the finite element method (FEM) software ANSYS and multi-body dynamics software SIMPACK are adopted respectively to establish the finite element model for bridge and the multi-body vehicle. A co-simulation method is employed to investigate the vehicle-bridge coupling vibration for the transit system. The traffic operation factors, including train formation, track irregularity and tire stiffness, are incorporated into the models separately to analyze the bridge and vehicle responses. The results show that the coupling of dynamic effects of the suspended monorail system between vehicle and bridge are significant in the case studied, and it is strongly suggested to take necessary measures for vibration suppression. The simulation of track irregularity is a critical factor for its vibration safety, and the track irregularity of A-level road roughness negatively influences the system vibration safety. PMID:27834923
Kinematic Simulation of a universal rescue vehicle
NASA Astrophysics Data System (ADS)
Vasiliev, I. A.; Smirnova, E. Y.; Krasheninnikov, M. S.; Koshurina, A. A.; Dorofeev, R. A.; E Gai, V.
2017-01-01
The rescue of people in disaster through autonomous means of evacuation in some cases is the only way to save their lives. Rescue Mission often takes place in remote locations. The paper studies modeling of a universal rescue vehicle with a rotary-screw propeller.
McEvoy, Suzanne P; Stevenson, Mark R; Woodward, Mark
2007-11-01
There is evidence that mobile phone use while driving (including hands-free) is associated with motor vehicle crashes. However, whether the effects of mobile phone use differ from that of passengers in the vehicle remains unclear. The aim of this research was to estimate the risk of crash associated with passenger carriage and compare that with mobile phone use. A case-control study ('passenger study') was performed in Perth, Western Australia in 2003 and 2004. Cases were 274 drivers who attended hospital following a motor vehicle crash and controls were 1096 drivers (1:4 matching) recruited at service stations matched to the location and time and day of week of the crash. The results were compared with those of a case-crossover study ('mobile phone study') undertaken concurrently (n=456); 152 cases were common to both studies. Passenger carriage increased the likelihood of a crash (adjusted odds ratio (adj. OR), 95% confidence interval (95% CI), 1.6, 1.1-2.2). Drivers carrying two or more passengers were twice as likely to crash as unaccompanied drivers (adj. OR 2.2, 95% CI 1.3-3.8). By comparison, driver's use of a mobile phone within 5 min before a crash was associated with a fourfold increased likelihood of crashing (OR 4.1, 95% CI 2.2-7.7). Passenger carriage and increasing numbers of passengers are associated with an increased likelihood of crash, though not to the same extent as mobile phone use. Further research is needed to investigate the factors underlying the increased risks.
2010-01-01
Background Heavy vehicle transportation continues to grow internationally; yet crash rates are high, and the risk of injury and death extends to all road users. The work environment for the heavy vehicle driver poses many challenges; conditions such as scheduling and payment are proposed risk factors for crash, yet the precise measure of these needs quantifying. Other risk factors such as sleep disorders including obstructive sleep apnoea have been shown to increase crash risk in motor vehicle drivers however the risk of heavy vehicle crash from this and related health conditions needs detailed investigation. Methods and Design The proposed case control study will recruit 1034 long distance heavy vehicle drivers: 517 who have crashed and 517 who have not. All participants will be interviewed at length, regarding their driving and crash history, typical workloads, scheduling and payment, trip history over several days, sleep patterns, health, and substance use. All participants will have administered a nasal flow monitor for the detection of obstructive sleep apnoea. Discussion Significant attention has been paid to the enforcement of legislation aiming to deter problems such as excess loading, speeding and substance use; however, there is inconclusive evidence as to the direction and strength of associations of many other postulated risk factors for heavy vehicle crashes. The influence of factors such as remuneration and scheduling on crash risk is unclear; so too the association between sleep apnoea and the risk of heavy vehicle driver crash. Contributory factors such as sleep quality and quantity, body mass and health status will be investigated. Quantifying the measure of effect of these factors on the heavy vehicle driver will inform policy development that aims toward safer driving practices and reduction in heavy vehicle crash; protecting the lives of many on the road network. PMID:20338064
Gawron, James H; Keoleian, Gregory A; De Kleine, Robert D; Wallington, Timothy J; Kim, Hyung Chul
2018-03-06
Although recent studies of connected and automated vehicles (CAVs) have begun to explore the potential energy and greenhouse gas (GHG) emission impacts from an operational perspective, little is known about how the full life cycle of the vehicle will be impacted. We report the results of a life cycle assessment (LCA) of Level 4 CAV sensing and computing subsystems integrated into internal combustion engine vehicle (ICEV) and battery electric vehicle (BEV) platforms. The results indicate that CAV subsystems could increase vehicle primary energy use and GHG emissions by 3-20% due to increases in power consumption, weight, drag, and data transmission. However, when potential operational effects of CAVs are included (e.g., eco-driving, platooning, and intersection connectivity), the net result is up to a 9% reduction in energy and GHG emissions in the base case. Overall, this study highlights opportunities where CAVs can improve net energy and environmental performance.
Development of a traffic noise prediction model for an urban environment.
Sharma, Asheesh; Bodhe, G L; Schimak, G
2014-01-01
The objective of this study is to develop a traffic noise model under diverse traffic conditions in metropolitan cities. The model has been developed to calculate equivalent traffic noise based on four input variables i.e. equivalent traffic flow (Q e ), equivalent vehicle speed (S e ) and distance (d) and honking (h). The traffic data is collected and statistically analyzed in three different cases for 15-min during morning and evening rush hours. Case I represents congested traffic where equivalent vehicle speed is <30 km/h while case II represents free-flowing traffic where equivalent vehicle speed is >30 km/h and case III represents calm traffic where no honking is recorded. The noise model showed better results than earlier developed noise model for Indian traffic conditions. A comparative assessment between present and earlier developed noise model has also been presented in the study. The model is validated with measured noise levels and the correlation coefficients between measured and predicted noise levels were found to be 0.75, 0.83 and 0.86 for case I, II and III respectively. The noise model performs reasonably well under different traffic conditions and could be implemented for traffic noise prediction at other region as well.
Brumbelow, Matthew L; Mueller, Becky C; Arbelaez, Raul A
2015-01-01
The Insurance Institute for Highway Safety (IIHS) introduced its side impact consumer information test program in 2003. Since that time, side airbags and structural improvements have been implemented across the fleet and the proportion of good ratings has increased to 93% of 2012-2014 model year vehicles. Research has shown that drivers of good-rated vehicles are 70% less likely to die in a left-side crash than drivers of poor-rated vehicles. Despite these improvements, side impact fatalities accounted for about one quarter of passenger vehicle occupant fatalities in 2012. This study is a detailed analysis of real-world cases with serious injury resulting from side crashes of vehicles with good ratings in the IIHS side impact test. NASS-CDS and Crash Injury Research and Engineering Network (CIREN) were queried for occupants of good-rated vehicles who sustained an Abbreviated Injury Scale (AIS) ≥ 3 injury in a side-impact crash. The resulting 110 cases were categorized by impact configuration and other factors that contributed to injury. Patterns of impact configuration, restraint performance, and occupant injury were identified and discussed in the context of potential upgrades to the current IIHS side impact test. Three quarters of the injured occupants were involved in near-side impacts. For these occupants, the most common factors contributing to injury were crash severities greater than the IIHS test, inadequate side-airbag performance, and lack of side-airbag coverage for the injured body region. In the cases where an airbag was present but did not prevent the injury, occupants were often exposed to loading centered farther forward on the vehicle than in the IIHS test. Around 40% of the far-side occupants were injured from contact with the struck-side interior structure, and almost all of these cases were more severe than the IIHS test. The remaining far-side occupants were mostly elderly and sustained injury from the center console, instrument panel, or seat belt. In addition, many far-side occupants were likely out of position due to events preceding the side impact and/or being unbelted. Individual changes to the IIHS side impact test have the potential to reduce the number of serious injuries in real-world crashes. These include impacting the vehicle farther forward (relevant to 28% of all cases studied), greater test severity (17%), the inclusion of far-side occupants (9%), and more restrictive injury criteria (9%). Combinations of these changes could be more effective.
Guidelines for Evaluating the Thermal Environment of Enclosed Spaces
2009-09-01
space. Three studies of concrete tanks and metal containers, the High Mobility Multipurpose Wheeled Vehicle; and the Bradley Fighting Vehicle, are...24 13 The initial CST-WMD training site was a concrete casting site. The teams practiced entry and evacuation...Environmental Medicine (USARIEM) studies. Examples are presented from three case studies: one that involved monitoring large concrete septic tanks
Simic, Vladimir; Dimitrijevic, Branka
2015-02-01
An interval linear programming approach is used to formulate and comprehensively test a model for optimal long-term planning of vehicle recycling in the Republic of Serbia. The proposed model is applied to a numerical case study: a 4-year planning horizon (2013-2016) is considered, three legislative cases and three scrap metal price trends are analysed, availability of final destinations for sorted waste flows is explored. Potential and applicability of the developed model are fully illustrated. Detailed insights on profitability and eco-efficiency of the projected contemporary equipped vehicle recycling factory are presented. The influences of the ordinance on the management of end-of-life vehicles in the Republic of Serbia on the vehicle hulks procuring, sorting generated material fractions, sorted waste allocation and sorted metals allocation decisions are thoroughly examined. The validity of the waste management strategy for the period 2010-2019 is tested. The formulated model can create optimal plans for procuring vehicle hulks, sorting generated material fractions, allocating sorted waste flows and allocating sorted metals. Obtained results are valuable for supporting the construction and/or modernisation process of a vehicle recycling system in the Republic of Serbia. © The Author(s) 2015.
Design study of toroidal traction CVT for electric vehicles
NASA Technical Reports Server (NTRS)
Raynard, A. E.; Kraus, J.; Bell, D. D.
1980-01-01
The development, evaluation, and optimization of a preliminary design concept for a continuously variable transmission (CVT) to couple the high-speed output shaft of an energy storage flywheel to the drive train of an electric vehicle is discussed. An existing computer simulation program was modified and used to compare the performance of five CVT design configurations. Based on this analysis, a dual-cavity full-toroidal drive with regenerative gearing is selected for the CVT design configuration. Three areas are identified that will require some technological development: the ratio control system, the traction fluid properities, and evaluation of the traction contact performance. Finally, the suitability of the selected CVT design concept for alternate electric and hybrid vehicle applications and alternate vehicle sizes and maximum output torques is determined. In all cases the toroidal traction drive design concept is applicable to the vehicle system. The regenerative gearing could be eliminated in the electric powered vehicle because of the reduced ratio range requirements. In other cases the CVT with regenerative gearing would meet the design requirements after appropriate adjustments in size and reduction gearing ratio.
An Analysis of Children Left Unattended in Parked Motor Vehicles in Brazil
Costa, Driely; Grundstein, Andrew
2016-01-01
Our study investigates the incidence of children left unattended in parked motor vehicles in Brazil. These events have been widely explored in the United States but less so abroad, and never in Brazil. Over the period from 2006 to 2015, we collected data from news reports on 31 cases, including 21 fatalities. The circumstances mostly involved a caregiver, especially a parent, forgetting the child (71%), but cases also included the child being intentionally left in the vehicle (23%) or gaining access to the vehicle (3%). Children tended to be forgotten more frequently in fatal cases (86%), particularly on the way to daycare, than non-fatal incidents where circumstances were more evenly distributed between forgetting (40%) and being intentionally left behind (50%). Incidents occurred throughout the country but mostly in the southeastern region near the city of São Paulo. Additionally, the danger for children is present year-round as we observed cases in every season, albeit with a peak in the summer. This heat-related hazard is not well recognized across Brazil and we recommend increasing awareness through education. Further, given the high percentage of cases involving parents forgetting to leave their children at daycare, we recommend arrangements between daycare providers and parents to communicate when a child does not attend as expected. PMID:27399747
Assessing crash risk considering vehicle interactions with trucks using point detector data.
Hyun, Kyung Kate; Jeong, Kyungsoo; Tok, Andre; Ritchie, Stephen G
2018-03-12
Trucks have distinct driving characteristics in general traffic streams such as lower speeds and limitations in acceleration and deceleration. As a consequence, vehicles keep longer headways or frequently change lane when they follow a truck, which is expected to increase crash risk. This study introduces several traffic measures at the individual vehicle level to capture vehicle interactions between trucks and non-trucks and analyzed how the measures affect crash risk under different traffic conditions. The traffic measures were developed using headways obtained from Inductive Loop Detectors (ILDs). In addition, a truck detection algorithm using a Gaussian Mixture (GM) model was developed to identify trucks and to estimate truck exposure from ILD data. Using the identified vehicle types from the GM model, vehicle interaction metrics were categorized into three groups based on the combination of leading and following vehicle types. The effects of the proposed traffic measures on crash risk were modeled in two different cases of prior- and non-crash using a case-control approach utilizing a conditional logistic regression. Results showed that the vehicle interactions between the leading and following vehicle types were highly associated with crash risk, and further showed different impacts on crash risk by traffic conditions. Specifically, crashes were more likely to occur when a truck following a non-truck had shorter average headway but greater headway variance in heavy traffic while a non-truck following a truck had greater headway variance in light traffic. This study obtained meaningful conclusions that vehicle interactions involved with trucks were significantly related to the crash likelihood rather than the measures that estimate average traffic condition such as total volume or average headway of the traffic stream. Copyright © 2018 Elsevier Ltd. All rights reserved.
A Fully Directional Universal Power Electronic Interface for EV, HEV, and PHEV Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Onar, Omer C
2012-01-01
This study focuses on a universal power electronic interface that can be utilized in any type of the electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles (PHEVs). Basically, the proposed converter interfaces the energy storage device of the vehicle with the motor drive and the external charger, in case of PHEVs. The proposed converter is capable of operating in all directions in buck or boost modes with a noninverted output voltage (positive output voltage with respect to the input) and bidirectional power flow.
Teaching case studies on the regulation of motor vehicle air pollution in China.
DOT National Transportation Integrated Search
2009-12-23
Motor vehicle air pollution is a critical component of China's severe air quality problem and has the potential to become an even greater issue in the years to come. On this project, the principal investigator and research staff are developing Harvar...
Vehicle Guidance and Control Along Circular Trajectories
1992-09-01
the line of sight, while Chism [2] studied a cross track error based control law. Hawkinson [3] extended the results to the multiple input case when...Thesis, Naval Postgraduate School, Monterey, California, June. 2. Chism , S., (1990) "Robust path tracking of autonomous underwater vehicles using sliding
NASA Astrophysics Data System (ADS)
Ramdhani, M. N.; Baihaqi, I.; Siswanto, N.
2018-04-01
Waste collection and disposal become a major problem for many metropolitan cities. Growing population, limited vehicles, and increased road traffic make the waste transportation become more complex. Waste collection involves some key considerations, such as vehicle assignment, vehicle routes, and vehicle scheduling. In the scheduling process, each vehicle has a scheduled departure that serve each route. Therefore, vehicle’s assignments should consider the time required to finish one assigment on that route. The objective of this study is to minimize the number of vehicles needed to serve all routes by developing a mathematical model which uses assignment problem approach. The first step is to generated possible routes from the existing routes, followed by vehicle assignments for those certain routes. The result of the model shows fewer vehicles required to perform waste collection asa well as the the number of journeys that the vehicle to collect the waste to the landfill. The comparison of existing conditions with the model result indicates that the latter’s has better condition than the existing condition because each vehicle with certain route has an equal workload, all the result’s model has the maximum of two journeys for each route.
10 CFR 71.47 - External radiation standards for all packages.
Code of Federal Regulations, 2011 CFR
2011-01-01
...); or in the case of a flat-bed style vehicle, at any point 2 meters (6.6 feet) from the vertical planes... of the vehicle; or in the case of a flat-bed style vehicle, at any point on the vertical planes...
Influence of structural dynamics on vehicle design - Government view. [of aerospace vehicles
NASA Technical Reports Server (NTRS)
Kordes, E. E.
1977-01-01
Dynamic design considerations for aerospace vehicles are discussed, taking into account fixed wing aircraft, rotary wing aircraft, and launch, space, and reentry vehicles. It is pointed out that space vehicles have probably had the most significant design problems from the standpoint of structural dynamics, because their large lightweight structures are highly nonlinear. Examples of problems in the case of conventional aircraft include the flutter encountered by high performance military aircraft with external stores. A description is presented of a number of examples which illustrate the direction of present efforts for improving aircraft efficiency. Attention is given to the results of studies on the structural design concepts for the arrow-wing supersonic cruise aircraft configuration and a system study on low-wing-loading, short haul transports.
Alternative Fuels Data Center: Texas Transportation Data for Alternative
National Renewable Energy Laboratory Case Studies Video thumbnail for Electric Vehicles Take Center Stage in North Texas Electric Vehicles Take Center Stage in North Texas June 30, 2016 Video thumbnail for Texas through Supplemental Environmental Projects (SEPs) April 20, 2016 Video thumbnail for Houston
NASA Astrophysics Data System (ADS)
Suthikarnnarunai, N.; Olinick, E.
2009-01-01
We present a case study on the application of techniques for solving the Vehicle Routing Problem (VRP) to improve the transportation service provided by the University of The Thai Chamber of Commerce to its staff. The problem is modeled as VRP with time windows, split deliveries, and a mixed fleet. An exact algorithm and a heuristic solution procedure are developed to solve the problem and implemented in the AMPL modeling language and CPLEX Integer Programming solver. Empirical results indicate that the heuristic can find relatively good solutions in a small fraction of the time required by the exact method. We also perform sensitivity analysis and find that a savings in outsourcing cost can be achieved with a small increase in vehicle capacity.
Blows, Stephanie; Ivers, Rebecca Q; Connor, Jennie; Ameratunga, Shanthi; Norton, Robyn
2003-01-01
This paper examines the association between periodic motor vehicle inspection and frequent tire pressure checks, and the risk of car crash injury. Data were analysed from the Auckland Car Crash Injury Study, a population-based case-control study in Auckland, NZ, where vehicles are required to undergo six-monthly safety inspections. Cases were all cars involved in crashes in which at least one occupant was hospitalised or killed, which represented 571 drivers. Controls were randomly selected cars on Auckland roads (588 drivers). Participants completed a structured interview. Vehicles that did not have a current certificate of inspection had significantly greater odds of being involved in a crash where someone was injured or killed compared with cars that had a current certificate, after adjustment for age, sex, marijuana use, ethnicity and licence type (OR 3.08, 95% CI 1.87-5.05). Vehicles that had not had their tire pressure checked within the past three months also had significantly greater odds of being involved in a crash compared with those that had a tire pressure check, after adjustment for age, sex, ethnicity, seatbelt use, licence type, self-reported speed and hours per week of driving exposure (OR 1.89, 95% CI 1.16-3.08). This study provides new evidence, using rigorous epidemiological methods and controlling for multiple confounding variables, of an association between periodic vehicle inspections and three-monthly tire pressure checks and reduced risk of car crash injury. This research suggests that vehicle inspection programs should be continued where they already exist and contributes evidence in support of introducing such programs to other areas.
Self-employment as a solution for attitudinal barriers: a case study.
Quinton, Melanie C
2014-01-01
This paper uses a case study to examine attitudinal barriers to employment and underemployment. We follow the career path of PR, a woman with multiple physical impairments, as she seeks financial independence through several employment strategies. In these, she faced attitudinal barriers and employment situations without opportunity for advancement. Eventually, PR opens her own business, turning to an alternative loan program to acquire the funds necessary to purchase a ready-made vehicle that matches her needs for accessible transportation. Use of this vehicle to provide delivery services for her business has more than doubled her income.
ERIC Educational Resources Information Center
Warmerdam, John; And Others
Training in the motor vehicle repair and sales sector in the Netherlands was examined in a study that included the following approaches: review of the sector's structure/characteristics, institutional and social context, employment practices, changing conditions, and available education and training; in-depth case studies of four auto repair shops…
Dynamic Load on Continuous Multi-Lane Bridge Deck from Moving Vehicles
NASA Astrophysics Data System (ADS)
ZHU, X. Q.; LAW, S. S.
2002-04-01
The dynamic loading on a multi-lane continuous bridge deck due to vehicles moving on top at a constant velocity is investigated. The bridge is modelled as a multi-span continuous orthotropic rectangular plate with line rigid intermediate supports. The vehicle is simulated as a two-axle three-dimensional vehicle model with seven degrees of freedom according to the H20-44 vehicle design loading (AASHTO LRFD Bridge Design Specifications 1998 American Association of State Highway and Transportation Officials [1]). The dynamic behavior of the bridge deck under single and several vehicles moving in different lanes is analyzed using the orthotropic plate theory and modal superposition technique. The dynamic loading is studied in terms of the dynamic impact factor of the bridge deck. The impact factor is found varying in an opposite trend as the dynamic responses for the different loading cases under study.
Integrating Human Factors into Crew Exploration Vehicle (CEV) Design
NASA Technical Reports Server (NTRS)
Whitmore, Mihriban; Holden, Kritina; Baggerman, Susan; Campbell, Paul
2007-01-01
The purpose of this design process is to apply Human Engineering (HE) requirements and guidelines to hardware/software and to provide HE design, analysis and evaluation of crew interfaces. The topics include: 1) Background/Purpose; 2) HE Activities; 3) CASE STUDY: Net Habitable Volume (NHV) Study; 4) CASE STUDY: Human Modeling Approach; 5) CASE STUDY: Human Modeling Results; 6) CASE STUDY: Human Modeling Conclusions; 7) CASE STUDY: Human-in-the-Loop Evaluation Approach; 8) CASE STUDY: Unsuited Evaluation Results; 9) CASE STUDY: Suited Evaluation Results; 10) CASE STUDY: Human-in-the-Loop Evaluation Conclusions; 11) Near-Term Plan; and 12) In Conclusion
Motor vehicle driver death and high state maximum speed limits: 1991-1993.
Yamane, Grover K; Bradshaw, Benjamin S
2008-09-01
To measure the association between motor vehicle crash (MVC) driver death and high state maximum speed limits. This study used a case-control design and assessed driver deaths from three major types of MVCs: non-collision; collision with motor vehicles in transit; and collision with stationary objects. The study period was 1991-1993. For each type of crash, case subject populations of fatally injured drivers were obtained from the U.S. Department of Transportation Fatality Analysis Reporting System. Four control subject populations, each associated with a different cause of death, were obtained from a U.S. national death certificate database (the causes of death were unintentional poisoning, non-Hodgkin lymphoma, drowning, and diabetes mellitus). Subjects were considered exposed if the state in which they crashed (for cases) or died (for controls) had a maximum speed limit greater than 55 mph. Each of the three case subject populations was compared against each of the four control subject populations. Odds ratios (ORs) were adjusted for age and gender. For non-collision driver death, ORs ranged from 3.06 to 6.56, depending on the year and control group; all the ORs were significant. For collision with motor vehicles in transit driver death, ORs ranged from 1.12 to 2.22; all the ORs were significant. For collision with stationary objects driver death, ORs ranged from 0.87 to 1.83. There was a moderately strong and significant association between non-collision driver death and high state maximum speed limits. For collision with motor vehicles in transit driver death, the association was somewhat milder but still consistent. For collision with stationary objects driver death, the presence of an association was unclear. During 1991-1993, the effects of high state maximum speed limits may have been different for different types of MVCs.
Toll facilities in the United States : bridges, roads, tunnels, ferries
DOT National Transportation Integrated Search
1994-06-01
Minnesota Guidestar's Travlink and Genesis operational tests were chosen by the FHWA to be the subjects of case studies. The case studies were performed under the Intelligent Vehicle Highway Systems Institutional and Legal Issues Program, which was d...
Viano, David C; Parenteau, Chantal S
2018-06-21
This study investigated trends in severe injury and ejection in rollover crashes involving lap-shoulder belted drivers and right-front passengers. It was conducted because of changes in 2009 to consumer information programs and regulations related to rollover protection. The data is presented by model year (MY) of the vehicle in groups from 1995-2016. NASS-CDS cases with 2010-16 MY vehicles were also evaluated to determine the crash circumstances and causes for severe injury of belted occupants in vehicles with a high strength-to-weight (SWR) roof, curtain and side airbags and other safety improvements. 1997-2015 NASS-CDS data was evaluated for severe injury and ejection of lap-shoulder belted front-outboard occupants in light vehicles. Crashes were grouped by front, side, rear and rollover. The injury and ejection data was grouped by vehicle MY: 1995-99, 2000-04, 2005-09 and 2010-16. Only drivers and right-front passengers were included if they were lap-shoulder belted and 15+ years old. Severely injured occupants were defined as those with MAIS 4-6 or fatality (MAIS 4+F). National estimates were made with weighted data using the ratio weight in NASS-CDS. All NASS-CDS electronic cases were evaluated for belted occupants with MAIS 4+F injury in rollovers involving 2010-16 MY vehicles. The crash circumstances and injuries were studied. These vehicles had high SWR roofs to meet IIHS ratings and FMVSS 216. The 1997-2015 NASS-CDS included 2,083,776 belted front occupants in rollover crashes with 24,466 (1.17%) MAIS 4+F injuries. The frequency of rollover crashes has decreased with modern vehicles (p < 0.0001). The 1995-1999 MY vehicles involved in a rollover accounted for 7.03% of all crashes (756,228/10,760,000). The corresponding proportion was 3.57% with 2010-2016 MY vehicles (81,406 v 2,282,062). The risk for MAIS 4+F was 1.325 ± 0.347% in rollover crashes with 1995-99 MY vehicles. It was 27.2% lower in 2010-16 MY vehicles at 0.964 ± 0.331% (p < 0.001). There were 42,567 (2.002%) ejections of belted occupants in rollover crashes, irrespective of injury outcome. The risk for ejection was 3.042 ± 1.44% in rollover crashes with 1995-99 MY vehicles. It was 43.6% lower in 2004-2009 MY vehicle at 1.715 ± 0.660% (p <0.001) and 83.4% lower in 2010-16 MY vehicle at 0.505 ± 0.336% (p < 0.001). There were 17 rollovers with MAIS 4+F in 2010-16 MY vehicles in NASS-CDS. Their roof strength was SWR = 4.15 ± 1.05 based on 15 vehicles. Many of the collisions involved front or side impacts and then a rollover. Four cases involved 16-30 year old drivers in extremely high-speed loss of control crashes resulting in >10 cm vertical roof deformation or substantial roof deformation based on photos. The roof strength (SWR) of 4.20 ± 1.0 was not sufficient to prevent roof deformation in these crashes. This study found a reduction in severe injury and ejection risk with modern vehicles. It indicates vehicle safety has improved in response to IIHS and NHTSA efforts to expand the array of safety requirements and increase performance so that newer models are safer than earlier ones. There has been an incremental improvement in safety by these advances.
49 CFR 173.441 - Radiation level limitations and exclusive use provisions.
Code of Federal Regulations, 2011 CFR
2011-10-01
...; or in the case of a flat-bed style vehicle, at any point on the vertical planes projected from the... external surface of the vehicle; (3) 0.1 mSv/h (10 mrem/h) at any point 2 m (6.6 feet) from the outer lateral surfaces of the vehicle (excluding the top and underside of the vehicle); or in the case of a flat...
NASA Astrophysics Data System (ADS)
Danca, Paul; Bode, Florin; Nastase, Ilinca; Meslem, Amina
2018-02-01
Nowadays, thermal comfort became one of the criteria in choosing a vehicle. In last decades time spent by people in vehicles had risen substantially. During each trip, thermal comfort must to be ensured for a good psychological and physical state of the passengers. Also, a comfortable environment leads to a higher power concentration of the driver thereby to a safe trip for vehicle occupants and for all traffic participants. The present study numerically investigated the effect of human body sited in the driver's place, over the air velocity distribution and over the thermal comfort in a passenger compartment. CFD simulations were made with different angles of the left inlet grill, in both cases, with and without driver presence. In majority of the actual vehicles environment studies, are made without consideration of human body geometry, in this case, the results precision can be affected. The results show that the presence of human body, lead to global changing of the whole flow pattern inside the vehicular cabin. Also, the locations of the maximum velocities are changing with the angle of the guiding vanes. The thermal comfort PMV/PPD indexes were calculated for each case. The presence of human body leads to a more comfortable environment.
Bunn, T L; Slavova, S; Struttmann, T W; Browning, S R
2005-09-01
A retrospective population-based case-control study was conducted to determine whether driver sleepiness/fatigue and inattention/distraction increase the likelihood that a commercial motor vehicle collision (CVC) will be fatal. Cases were identified as CVC drivers who died (fatal) and controls were drivers who survived (nonfatal) an injury collision using the Kentucky Collision Report Analysis for Safer Highways (CRASH) electronic database from 1998-2002. Cases and controls were matched on unit type and roadway type. Conditional logistic regression was performed. Driver sleepiness/fatigue, distraction/inattention, age of 51 years of age and older, and nonuse of safety belts increase the odds that a CVC will be fatal. Primary safety belt law enactment and enforcement for all states, commercial vehicle driver education addressing fatigue and distraction and other approaches including decreased hours-of-service, rest breaks and policy changes, etc. may decrease the probability that a CVC will be fatal.
Fang, Pan; Lu, Jia; Liu, Ying-Hong; Deng, Hong-Mei; Zhang, Lei; Zhang, Hong-Qing
2018-06-01
Peritonitis, which is one of the leading complications of peritoneal dialysis (PD) worldwide, severely affected morbidity and mortality of the PD patients. Although many efforts have been made to prevent PD-related peritonitis, it seems impossible to prevent it completely. Many causes have been reported to lead to peritonitis, and contamination during bag exchange is one of the important risk factors for peritonitis. Here, we introduce an operating vehicle, which we invented to provide a sterile and safe space for bag exchange. A single-center, retrospective, case-control study was undertaken to determine whether this operating vehicle has a protective role in preventing peritonitis. In total, 462 continuous ambulatory peritoneal dialysis patients were included in this study from October 2014 to March 2017. According to their personal will, these patients chose to use operating vehicle or traditional method during their bag exchange. The demographic, clinical and laboratory data of these patients in the two groups were collected, analyzed and compared. Of 462 patients with home dialysis, operating vehicle group consisted of 61 patients, and control group consisted of 401 patients. In the control group, over 677 patient-years, peritonitis occurred in 69 of 401 patients (17.2%), while in the operating vehicle group, over 60 patient-years, only 4 of 61 patients (6.6%) had episodes of peritonitis. The number of patients suffered from peritonitis was significantly decreased in the operating vehicle group (P = 0.034). Besides, there were a total of 99 episodes of peritonitis, and the rate was 1 episode every 7.2 patient-years in control group and 1 episode every 12 patient-years in the operating vehicle group. There was significant difference between the two groups (0.013). Positive dialysate cultures were obtained in majority of the peritonitis episodes (60.6%). Operating vehicle might help to reduce PD-related peritonitis by preventing contamination during bag exchange. Further studies are still needed to demonstrate the protective role of the operating vehicle in preventing peritonitis.
[Factors associated with road accidents in the city of Lubumbashi].
Kandolo, Simon Ilunga; Matungulu, Charles Matungulu; Mukanya, Pascal Kimba; Umba, Irène Kabange; Kabamba, Julie Ndayi; Numbi, Oscar Luboya; Ilunga, Benjamin Kabyla; Kaj, Françoise Malonga; Lubaba, Célestin Banza; Ngongo, Ghislain Mashini
2014-01-01
We conducted a retrospective non-comparative cross-sectional study in Lubumbashi on factors associated with road accidents. To contribute to the reduction of morbidity and mortality related to road accidents based on a better understanding of this phenomenon in the city of Lubumbashi, to assess the frequency and the growth of road accidents in the city of Lubumbashi and to determine the factors predisposing to these accidents. This non-controlled retrospective cross-sectional descriptive study covered the period from 1st January to 31st December 2008, and included all cases of vehicles registered by the police department after an accident. A total of 1,915 road traffic were reported, mostly caused by public transport vehicles (59%) driven by young adult males (89% of cases) with a mean age of 28 years. The main cause was speeding combined with other factors (34% of cases). The majority of these accidents occurred in the city of Lubumbashi (52.9% of cases) between 6:00 a.m. and 6:00 p.m. (74% of cases). Transit vehicles were exposed to a greater risk of road accidents (59%). There is an urgent need for accurate information on the rules of the road for drivers and road users to reduce the mortality and morbidity due to road accidents.
Mission and space vehicle sizing data for a chemical propulsion/aerobraking option
NASA Technical Reports Server (NTRS)
Butler, John; Brothers, Bobby
1986-01-01
Sizing data is presented for various combinations of Mars missions and chemical-propulsion/aerobraking vehicles. Data is compared for vehicles utilizing opposition (2-year mission) and conjunction (3-year mission) trajectories for 1999 and 2001 opportunities, for various sizes of vehicles. Payload capabilities for manned and unmanned missions vehicles and for propulsive-braking and aerobraking cases are shown. The effect of scaling up a reference vehicle is compared to the case of utilizing two identical vehicles, for growth in payload capability. The rate of cumulative build up of weight on the surface of Mars is examined for various mission/vehicle combinations, and is compared to the landed-weight requirements for sortie missions, moving-base missions, and fixed-base missions. Also, the required buildup of weight in low Earth orbit (LEO) for various mission/vehicle combinations is presented and discussed.
[Fatal occupational accidents in Lombardy].
Pianosi, G
1995-01-01
All fatal occupational accidents compensated in Lombardy from 1984 to 1989 were analyzed (1259 cases): significant differences between geographical distribution of fatal occupational accidents and workers were observed. Males accounted for about 95% of fatalities; an excess of cases was shown in both young and elderly workers. Death was the consequence of injuries involving most frequently the head, thorax and spinal cord. An excess of fatalities was observed in agriculture and, at a lower level, in manufacturing industries; small enterprises were involved in approximately 25% of fatalities occurring in the manufacturing industries and services. Employers were the victims of fatal accidents in 50% of cases in agriculture and in 70% of cases in craft industries. Construction, agriculture and transport accounted for about 50% of all fatalities. About 50% of fatal occupational accidents were related to vehicle use: the victim was the driver in the majority of cases, sometimes the victim was run over by a vehicle or fell from a vehicle. The results agree with some previous observations (e.g.: sex and age distribution; construction, agriculture and transport as working activities at high accident risk); but some original observations have emerged, in particular about the frequency of employers as victims and the role of vehicles in the genesis of fatal occupational accidents. If further studies confirm these latter observations, important developments could follow in preventive action design and implementation.
LPV H-infinity Control for the Longitudinal Dynamics of a Flexible Air-Breathing Hypersonic Vehicle
NASA Astrophysics Data System (ADS)
Hughes, Hunter Douglas
This dissertation establishes the method needed to synthesize and simulate an Hinfinity Linear Parameter-Varying (LPV) controller for a flexible air-breathing hypersonic vehicle model. A study was conducted to gain the understanding of the elastic effects on the open loop system. It was determined that three modes of vibration would be suitable for the hypersonic vehicle model. It was also discovered from the open loop study that there is strong coupling in the hypersonic vehicle states, especially between the angle of attack, pitch rate, pitch attitude, and the exible modes of the vehicle. This dissertation outlines the procedure for synthesizing a full state feedback Hinfinity LPV controller for the hypersonic vehicle. The full state feedback study looked at both velocity and altitude tracking for the exible vehicle. A parametric study was conducted on each of these controllers to see the effects of changing the number of gridding points in the parameter space and changing the parameter variation rate limits in the system on the robust performance of the controller. As a result of the parametric study, a 7 x 7 grid ranging from Mach 7 to Mach 9 in velocity and from 70,000 feet to 90,000 feet in altitude, and a parameter variation rate limit of [.5 200]T was used for both the velocity tracking and altitude tracking cases. The resulting Hinfinity robust performances were gamma = 2.2224 for the velocity tracking case and = 1:7582 for the altitude tracking case. A linear analysis was then conducted on five different selected trim points from the Hinfinity LPV controller. This was conducted for the velocity tracking and altitude tracking cases. The results of linear analysis show that there is a slight difference in the response of the Hinfinity LPV controller and the fixed point H infinity controller. For the tracking task, the Hinfinity controller responds more quickly, and has a lower Hinfinity performance value. Next, the H infinity LPV controller was simulated using the nonlinear flexible hypersonic model for both the velocity tracking and altitude tracking cases. Both of these cases were subject to a ramp input and a multi-step input both with and without perturbation in the model. The results of the simulation show that the tracking state follows the command signal successfully though the perturbed system does show some higher frequency characteristics in the non-tracking states. It was discovered that there is an issue with integral windup when switching takes place in the controller, so an algorithm was implemented to reset the integration of the error on the tracking state when the switch takes place. It was also seen that there was a decline in altitude when tracking velocity, and a large change in velocity that occurred during altitude tracking. These results lead to the decision to include a unity gain regulation state on velocity for the altitude tracking and the altitude for the velocity tracking during the output feedback control synthesis. The procedure for synthesizing an output feedback H infinity LPV controller for the hypersonic vehicle is also discussed in this dissertation. The output feedback design looked at velocity tracking and altitude tracking with rigid body motion variables for both the exible and rigid body hypersonic vehicle models. As with the full state feedback controller, a parametric study was conducted on each of these controllers to determine the number of gridding points in the parameter space and the parameter variation rate limits in the system. The parametric study reveals a 7x7 grid ranging from Mach 7 to Mach 9 in velocity and from 70,000 feet to 90,000 feet in altitude, and a parameter variation rate limit of [.1 200]T is preferable for both the velocity tracking and altitude tracking cases with both the exible and rigid body assumptions. The resulting Hinfinity robust performances were gamma = 113:2146 for the exible body velocity tracking case, gamma = 83.6931 for the rigid body velocity tracking case, gamma = 107:2043 for the exible body altitude tracking case, and gamma = 97:7403 for the rigid body altitude tracking case. A linear analysis was then conducted on five different selected trim points from the Hinfinity LPV controller. The results of this analysis show that there is a larger difference in the response of the Hinfinity LPV controller and the Hinfinity controller. For the tracking task, the Hinfinity controller responds more quickly, and has a lower Hinfinity performance value. Next, the Hinfinity LPV controller was applied to the exible nonlinear plant model. The rigid body controllers were applied to the exible plant model to see if the exible nature of the vehicle could be treated as a perturbation to the system. Additionally, there were simulations run both with and without sensor noise and parametric uncertainty. The results of simulation show that the rigid body controller is able to successfully apply to the exible body model for the velocity tracking case, but is unable to stabilize the altitude tracking case. It was also seen that the system is able to track the command signal while minimizing the variations seen in the altitude for the velocity tracking case and in the velocity during the altitude tracking case. Additionally, there was no obvious effect of perturbations in the system on the tracking state or secondary regulation state. There were high frequency responses associated with the other perturbed states.
Wainiqolo, Iris; Kafoa, Berlin; Kool, Bridget; Robinson, Elizabeth; Herman, Josephine; McCaig, Eddie; Ameratunga, Shanthi
2016-01-01
To investigate the association between kava use and the risk of four-wheeled motor vehicle crashes in Fiji. Kava is a traditional beverage commonly consumed in many Pacific Island Countries. Herbal anxiolytics containing smaller doses of kava are more widely available. Data for this population-based case-control study were collected from drivers of 'case' vehicles involved in serious injury-involved crashes (where at least one road user was killed or admitted to hospital for 12 hours or more) and 'control' vehicles representative of 'driving time' in the study base. Structured interviewer administered questionnaires collected self-reported participant data on demographic characteristics and a range of risk factors including kava use and potential confounders. Unconditional logistic regression models estimated odds ratios relating to the association between kava use and injury-involved crash risk. Overall, 23% and 4% of drivers of case and control vehicles, respectively, reported consuming kava in the 12 hours prior to the crash or road survey. After controlling for assessed confounders, driving following kava use was associated with a four-fold increase in the odds of crash involvement (Odds ratio: 4.70; 95% CI: 1.90-11.63). The related population attributable risk was 18.37% (95% CI: 13.77-22.72). Acknowledging limited statistical power, we did not find a significant interaction in this association with concurrent alcohol use. In this study conducted in a setting where recreational kava consumption is common, driving following the use of kava was associated with a significant excess of serious-injury involved road crashes. The precautionary principle would suggest road safety strategies should explicitly recommend avoiding driving following kava use, particularly in communities where recreational use is common.
Fatalities due to intoxicated arrestees jumping out of moving police vehicles.
Jacobs, Werner
2006-12-01
Fatalities resulting from emergency vehicle crashes are relatively rare. Mortality, particularly in the case of unbelted occupants, is relatively high. Data on drunken (handcuffed) arrestees jumping out of a moving police vehicle or the circumstances of such events have not been published. Two cases of such fatalities are described in this paper. Since these cases should be considered as "death in custody," may give rise to significant covering and speculation in the media, and may raise liability questions, they require an in-depth medicolegal investigation, including investigation of the crime scene, complete medicolegal autopsy/toxicology, and reconstruction of the event in the presence of an experienced forensic pathologist. From the 2 cases described in this paper, it appears that mechanical malfunctioning of the locking device of the door of the police vehicle and lack of controlling the actual lock-tied closing of the vehicle door (instead just assuming that it happened) may precipitate such cases. Auditory control by the police officers of the arrestee tampering with or manipulating the car door may be hampered by the background noise of the police vehicle, the on-board radio, and the use of a siren. Regular visual control and adequate control of the actual locking of the vehicle door are of paramount importance to prevent such mishaps. Reconstruction of the event in the presence of the forensic experts is mandatory to test the different hypotheses of the fatal event.
DOT National Transportation Integrated Search
2008-12-01
This report presents the results of its performance assessment of the feasibility of applying cooperative vehicle- highway automation systems (CVHAS) to bus transit and freight movements in the metropolitan Chicago area. : CVHAS are systems that prov...
Factors that influence chest injuries in rollovers.
Digges, Kennerly; Eigen, Ana; Tahan, Fadi; Grzebieta, Raphael
2014-01-01
The design of countermeasures to reduce serious chest injuries for belted occupants involved in rollover crashes requires an understanding of the cause of these injuries and of the test conditions to assure the effectiveness of the countermeasures. This study defines rollover environments and occupant-to-vehicle interactions that cause chest injuries for belted drivers. The NASS-CDS was examined to determine the frequency and crash severity for belted drivers with serious (Abbreviated Injury Scale [AIS] 3+) chest injuries in rollovers. Case studies of NASS crashes with serious chest injuries sustained by belted front occupants were undertaken and damage patterns were determined. Vehicle rollover tests with dummies were examined to determine occupant motion in crashes with damage similar to that observed in the NASS cases. Computer simulations were performed to further explore factors that could contribute to chest injury. Finite element model (FEM) vehicle models with both the FEM Hybrid III dummy and THUMS human model were used in the simulations. Simulation of rollovers with 6 quarter-turns or less indicated that increases in the vehicle pitch, either positive or negative, increased the severity of dummy chest loadings. This finding was consistent with vehicle damage observations from NASS cases. For the far-side occupant, the maximum chest loadings were caused by belt and side interactions during the third quarter-turn and by the center console loading during the fourth quarter-turn. The results showed that the THUMS dummy produced more realistic kinematics and improved insights into skeletal and chest organ loadings compared to the Hybrid III dummy. These results suggest that a dynamic rollover test to encourage chest injury reduction countermeasures should induce a roll of at least 4 quarter-turns and should also include initial vehicle pitch and/or yaw so that the vehicle's axis of rotation is not aligned with its inertial roll axis during the initial stage of the rollover.
Spine Trauma Associated with Off-Road Vehicles.
ERIC Educational Resources Information Center
Reid, David C.; And Others
1988-01-01
A seven-year review of 1,447 cases of spine trauma showed that 53 cases were associated with the use of off-road vehicles, such as all-terrain vehicles, snowmobiles, and motorized dirt bikes. The development of safe riding areas, legislation governing safe operation, and public safety education are advised to curb this trend. (Author/JL)
Effects of turning and through lane sharing on traffic performance at intersections
NASA Astrophysics Data System (ADS)
Li, Xiang; Sun, Jian-Qiao
2016-02-01
Turning vehicles strongly influence traffic flows at intersections. Effective regulation of turning vehicles is important to achieve better traffic performance. This paper studies the impact of lane sharing and turning signals on traffic performance at intersections by using cellular automata. Both right-turn and left-turn lane sharing are studied. Interactions between vehicles and pedestrians are considered. The transportation efficiency, road safety and energy economy are the traffic performance metrics. Extensive simulations are carried out to study the traffic performance indices. It is observed that shared turning lanes and permissive left-turn signal improve the transportation efficiency and reduce the fuel consumption in most cases, but the safety is usually sacrificed. It is not always beneficial for the through vehicles when they are allowed to be in the turning lanes.
Stigson, Helena; Hill, Julian
2009-10-01
The objective of this study was to evaluate a model for a safe road transport system, based on some safety performance indicators regarding the road user, the vehicle, and the road, by using crashes with fatally and seriously injured car occupants. The study also aimed to evaluate whether the model could be used to identify system weaknesses and components (road user, vehicles, and road) where improvements would yield the highest potential for further reductions in serious injuries. Real-life car crashes with serious injury outcomes (Maximum Abbreviated Injury Scale 2+) were classified according to the vehicle's safety rating by Euro NCAP (European New Car Assessment Programme) and whether the vehicle was fitted with ESC (Electronic Stability Control). For each crash, the road was also classified according to EuroRAP (European Road Assessment Programme) criteria, and human behavior in terms of speeding, seat belt use, and driving under the influence of alcohol/drugs. Each crash was compared and classified according to the model criteria. Crashes where the safety criteria were not met in more than one of the 3 components were reclassified to identify whether all the components were correlated to the injury outcome. In-depth crash injury data collected by the UK On The Spot (OTS) accident investigation project was used in this study. All crashes in the OTS database occurring between 2000 and 2005 with a car occupant with injury rated MAIS2+ were included, for a total of 101 crashes with 120 occupants. It was possible to classify 90 percent of the crashes according to the model. Eighty-six percent of the occupants were injured when more than one of the 3 components were noncompliant with the safety criteria. These cases were reclassified to identify whether all of the components were correlated to the injury outcome. In 39 of the total 108 cases, at least two components were still seen to interact. The remaining cases were only related to one of the safety criteria, namely, the road user (26), the vehicle (19), and the road (24). The criteria for the road and the vehicle did not address multiple event crashes, rear-end crashes, hitting stationary/parked vehicles, or trailers. The model for a safe road transport system was found useful to classify fatal and serious road vehicle crashes. It was possible to classify 90 percent of the crashes according to the safety road transport model. For all these cases it was possible to identify weaknesses and parts of the road transport system with the highest potential to prevent fatal and serious injuries. Injury outcomes were mostly related to an interaction between the 3 components: the road, the vehicle, and the road user.
Upon the reconstruction of accidents triggered by tire explosion. Analytical model and case study
NASA Astrophysics Data System (ADS)
Gaiginschi, L.; Agape, I.; Talif, S.
2017-10-01
Accident Reconstruction is important in the general context of increasing road traffic safety. In the casuistry of traffic accidents, those caused by tire explosions are critical under the severity of consequences, because they are usually happening at high speeds. Consequently, the knowledge of the running speed of the vehicle involved at the time of the tire explosion is essential to elucidate the circumstances of the accident. The paper presents an analytical model for the kinematics of a vehicle which, after the explosion of one of its tires, begins to skid, overturns and rolls. The model consists of two concurent approaches built as applications of the momentum conservation and energy conservation principles, and allows determination of the initial speed of the vehicle involved, by running backwards the sequences of the road event. The authors also aimed to both validate the two distinct analytical approaches by calibrating the calculation algorithms on a case study
The Role of Habitability Studies in Space Facility and Vehicle Design
NASA Technical Reports Server (NTRS)
Adams, Constance M.
1999-01-01
This document is a viewgraph presentation which reviews the role of the space architect in designing a space vehicle with habitability as a chief concern. Habitability is composed of the qualities of the environment or system which support the crew in working and living. All the impacts from habitability are interdependent; i.e., impacts to well-being can impact performance, safety or efficiency. After reviewing the issues relating to habitability the presentation discusses the application of these issues in two case studies. The first studies the Bio-Plex Hab chamber which includes designs of the living and working areas. The second case study is the ISS-TransHab which is being studied as a prototype for Mars transit.
New Jersey I-80 and I-287 HOV lane case study
DOT National Transportation Integrated Search
2000-07-01
This report documents the New Jersey I-80 and I-287 high-occupancy vehicle (HOV) lane case study. Information is presented on planning, implementing, operating, and redesignating the HOV lanes on the two freeways. The operation of the lanes is compar...
NASA Technical Reports Server (NTRS)
D'souza, Sarah N.; Kinney, David J.; Garcia, Joseph A.; Sarigul-Klijn, Nesrin
2014-01-01
The state-of-the-art in vehicle design decouples flight feasible trajectory generation from the optimization process of an entry spacecraft shape. The disadvantage to this decoupled process is seen when a particular aeroshell does not meet in-flight requirements when integrated into Guidance, Navigation, and Control simulations. It is postulated that the integration of a guidance algorithm into the design process will provide a real-time, rapid trajectory generation technique to enhance the robustness of vehicle design solutions. The potential benefit of this integration is a reduction in design cycles (possible cost savings) and increased accuracy in the aerothermal environment (possible mass savings). This work examines two aspects: 1) the performance of a reference tracking guidance algorithm for five different geometries with the same reference trajectory and 2) the potential of mass savings from improved aerothermal predictions. An Apollo Derived Guidance (ADG) algorithm is used in this study. The baseline geometry and five test case geometries were flown using the same baseline trajectory. The guided trajectory results are compared to separate trajectories determined in a vehicle optimization study conducted for NASA's Mars Entry, Descent, and Landing System Analysis. This study revealed several aspects regarding the potential gains and required developments for integrating a guidance algorithm into the vehicle optimization environment. First, the generation of flight feasible trajectories is only as good as the robustness of the guidance algorithm. The set of dispersed geometries modelled aerodynamic dispersions that ranged from +/-1% to +/-17% and a single extreme case was modelled where the aerodynamics were approximately 80% less than the baseline geometry. The ADG, as expected, was able to guide the vehicle into the aeroshell separation box at the target location for dispersions up to 17%, but failed for the 80% dispersion cases. Finally, the results revealed that including flight feasible trajectories for a set of dispersed geometries has the potential to save mass up to 430 kg.
G and C boost and abort study summary, exhibit B
NASA Technical Reports Server (NTRS)
Backman, H. D.
1972-01-01
A six degree of freedom simulation of rigid vehicles was developed to study space shuttle vehicle boost-abort guidance and control techniques. The simulation was described in detail as an all digital program and as a hybrid program. Only the digital simulation was implemented. The equations verified in the digital simulation were adapted for use in the hybrid simulation. Study results were obtained from four abort cases using the digital program.
A novel framework to evaluate pedestrian safety at non-signalized locations.
Fu, Ting; Miranda-Moreno, Luis; Saunier, Nicolas
2018-02-01
This paper proposes a new framework to evaluate pedestrian safety at non-signalized crosswalk locations. In the proposed framework, the yielding maneuver of a driver in response to a pedestrian is split into the reaction and braking time. Hence, the relationship of the distance required for a yielding maneuver and the approaching vehicle speed depends on the reaction time of the driver and deceleration rate that the vehicle can achieve. The proposed framework is represented in the distance-velocity (DV) diagram and referred as the DV model. The interactions between approaching vehicles and pedestrians showing the intention to cross are divided in three categories: i) situations where the vehicle cannot make a complete stop, ii) situations where the vehicle's ability to stop depends on the driver reaction time, and iii) situations where the vehicle can make a complete stop. Based on these classifications, non-yielding maneuvers are classified as "non-infraction non-yielding" maneuvers, "uncertain non-yielding" maneuvers and "non-yielding" violations, respectively. From the pedestrian perspective, crossing decisions are classified as dangerous crossings, risky crossings and safe crossings accordingly. The yielding compliance and yielding rate, as measures of the yielding behavior, are redefined based on these categories. Time to crossing and deceleration rate required for the vehicle to stop are used to measure the probability of collision. Finally, the framework is demonstrated through a case study in evaluating pedestrian safety at three different types of non-signalized crossings: a painted crosswalk, an unprotected crosswalk, and a crosswalk controlled by stop signs. Results from the case study suggest that the proposed framework works well in describing pedestrian-vehicle interactions which helps in evaluating pedestrian safety at non-signalized crosswalk locations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Asymptotic Dynamics of Self-driven Vehicles in a Closed Boundary
NASA Astrophysics Data System (ADS)
Lee, Chi-Lun; Huang, Chia-Ling
2011-08-01
We study the asymptotic dynamics of self-driven vehicles in a loop using a car-following model with the consideration of volume exclusions. In particular, we derive the dynamical steady states for the single-cluster case and obtain the corresponding fundamental diagrams, exhibiting two branches representative of entering and leaving the jam, respectively. By simulations we find that the speed average over all vehicles eventually reaches the same value, regardless of final clustering states. The autocorrelation functions for overall speed average and single-vehicle speed are studied, each revealing a unique time scale. We also discuss the role of noises in vehicular accelerations. Based on our observations we give trial definitions about the degree of chaoticity for general self-driven many-body systems.
Vadeby, Anna; Forsman, Åsa
2017-06-01
This study investigated the effect of applying two aggregated models (the Power model and the Exponential model) to individual vehicle speeds instead of mean speeds. This is of particular interest when the measure introduced affects different parts of the speed distribution differently. The aim was to examine how the estimated overall risk was affected when assuming the models are valid on an individual vehicle level. Speed data from two applications of speed measurements were used in the study: an evaluation of movable speed cameras and a national evaluation of new speed limits in Sweden. The results showed that when applied on individual vehicle speed level compared with aggregated level, there was essentially no difference between these for the Power model in the case of injury accidents. However, for fatalities the difference was greater, especially for roads with new cameras where those driving fastest reduced their speed the most. For the case with new speed limits, the individual approach estimated a somewhat smaller effect, reflecting that changes in the 15th percentile (P15) were somewhat larger than changes in P85 in this case. For the Exponential model there was also a clear, although small, difference between applying the model to mean speed changes and individual vehicle speed changes when speed cameras were used. This applied both for injury accidents and fatalities. There were also larger effects for the Exponential model than for the Power model, especially for injury accidents. In conclusion, applying the Power or Exponential model to individual vehicle speeds is an alternative that provides reasonable results in relation to the original Power and Exponential models, but more research is needed to clarify the shape of the individual risk curve. It is not surprising that the impact on severe traffic crashes was larger in situations where those driving fastest reduced their speed the most. Further investigations on use of the Power and/or the Exponential model at individual vehicle level would require more data on the individual level from a range of international studies. Copyright © 2017 Elsevier Ltd. All rights reserved.
10 CFR 71.47 - External radiation standards for all packages.
Code of Federal Regulations, 2010 CFR
2010-01-01
... of the vehicle; or in the case of a flat-bed style vehicle, at any point on the vertical planes...); or in the case of a flat-bed style vehicle, at any point 2 meters (6.6 feet) from the vertical planes... controls. The instructions must be included with the shipping paper information. (d) The written...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephens, T. S.; Gonder, Jeff; Chen, Yuche
This report details a study of the potential effects of connected and automated vehicle (CAV) technologies on vehicle miles traveled (VMT), vehicle fuel efficiency, and consumer costs. Related analyses focused on a range of light-duty CAV technologies in conventional powertrain vehicles -- from partial automation to full automation, with and without ridesharing -- compared to today's base-case scenario. Analysis results revealed widely disparate upper- and lower-bound estimates for fuel use and VMT, ranging from a tripling of fuel use to decreasing light-duty fuel use to below 40% of today's level. This wide range reflects uncertainties in the ways that CAVmore » technologies can influence vehicle efficiency and use through changes in vehicle designs, driving habits, and travel behavior. The report further identifies the most significant potential impacting factors, the largest areas of uncertainty, and where further research is particularly needed.« less
Cherington, M
1995-12-01
It is a little-known fact that lightning casualties often involve travel or transportation. López and colleagues, in their studies on the epidemiology of lightning injuries, have reported that 10% of lightning injuries are categorized under transportation. In the majority of their cases, victims were struck while standing outside or near their vehicles during a thunderstorm. During my review of the neurologic complications of lightning injuries, I was impressed by the number of case reports in which the victim was struck while either in or near a vehicle, airplane or vessel. In this article, I shall put forth information on four aspects of lightning that relate to the danger to people traveling in vehicles, boats, and airplanes. First, I shall deal with lightning safety on ships and boats. People who enjoy recreational sailing, including the "weekend sailor" and those who enjoy fishing from a boat, should be fortified with knowledge about lightning protection. Second, I shall consider the matter of lightning strikes to aircraft. In the third section, I shall discuss the question of lightning safety in automobiles. Fourth, I shall review those cases found in my literature review in which the victim was struck while in or near a vehicle, boat, or airplane.
Nonequilibrium effects on the aerothermodynamics of transatmospheric and aerobraking vehicles
NASA Technical Reports Server (NTRS)
Hassan, Basil; Candler, Graham V.
1993-01-01
A 3D CFD algorithm is used to study the effect of thermal and chemical nonequilibrium on slender and blunt body aerothermodynamics. Both perfect gas and reacting gas air models are used to compute the flow over a generic transatmospheric vehicle and a proposed lunar transfer vehicle. The reacting air is characterized by a translational-rotational temperature and a vibrational-electron-electronic temperature and includes eight chemical species. The effects of chemical reaction, vibrational excitation, and ionization on lift-to-drag ratio and trim angle are investigated. Results for the NASA Ames All-body Configuration show a significant difference in center of gravity location for a reacting gas flight case when compared to a perfect gas wind tunnel case at the same Mach number, Reynolds number, and angle of attack. For the same center of gravity location, the wind tunnel model trims at lower angle of attack than the full-scale flight case. Nonionized and ionized results for a proposed lunar transfer vehicle compare well to computational results obtained from a previously validated reacting gas algorithm. Under the conditions investigated, effects of weak ionization on the heat transfer and aerodynamic coefficients were minimal.
Accident or Suicide? Single-Vehicle Car Accidents and the Intent Hypothesis.
ERIC Educational Resources Information Center
Peck, Dennis L.; Warner, Kenneth
1995-01-01
Brief case studies of single-vehicle car crashes are used to explore the relationship between this method of death and the intent to commit suicide. The author attempts to determine what criteria can be used to determine whether suicide was the intent, and how death by automobile crash can be determined a suicide. (JPS)
Alternative Fuels Data Center: Rightsizing Your Vehicle Fleet to Conserve
reducing fuel use. When rightsizing, fleet managers should evaluate how important each vehicle is to the rentals when needed? Case Study The City of Detroit generated $1 million in revenue working with the Clean should consider soliciting input from drivers when conducting a rightsizing review, as they can be very
Alternative Fuels Data Center: Alabama Transportation Data for Alternative
Renewable Energy Laboratory Case Studies Video thumbnail for Alabama Prisons Adopt Propane, Establish Fuel , 2016 Video thumbnail for City of Hoover Fleet Boasts 200-Plus Flex Fuel Vehicles City of Hoover Fleet Boasts 200-Plus Flex Fuel Vehicles May 24, 2013 Video thumbnail for Biodiesel Fuels Education in Alabama
Vehicle barrier with access delay
Swahlan, David J; Wilke, Jason
2013-09-03
An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.
Bus Stops and Pedestrian-Motor Vehicle Collisions in Lima, Peru: A Matched Case-Control Study
Quistberg, D. Alex; Koepsell, Thomas D.; Johnston, Brian D.; Boyle, Linda Ng; Miranda, J. Jaime; Ebel, Beth E.
2015-01-01
Objective To evaluate the relationship between bus stop characteristics and pedestrian-motor vehicle collisions. Design Matched case-control study where the units of study were pedestrian crossing. Setting Random sample of 11 police commissaries in Lima, Peru. Data collection occurred from February, 2011 to September, 2011. Participants 97 intersection cases representing 1,134 collisions and 40 mid-block cases representing 469 collisions that occurred between October, 2010 and January, 2011 and their matched controls. Main Exposures Presence of a bus stop and specific bus stop characteristics. Main Outcome Occurrence of a pedestrian-motor vehicle collision. Results Intersections with bus stops were three times more likely to have a pedestrian-vehicle collision (OR 3.28, 95% CI 1.53-7.03), relative to intersections without bus stops. Both formal and informal bus stops were associated with a higher odds of a collision at intersections (OR 6.23, 95% CI 1.76-22.0 and OR 2.98, 1.37-6.49). At mid-block sites, bus stops on a bus-dedicated transit lane were also associated with collision risk (OR 2.36, 95% CI 1.02-5.42). All bus stops were located prior to the intersection, contrary to practices in most high income countries. Conclusions In urban Lima, the presence of a bus stop was associated with a three-fold increase in risk of a pedestrian collision. The highly competitive environment among bus companies may provide an economic incentive for risky practices such as dropping off passengers in the middle of traffic and jockeying for position with other buses. Bus stop placement should be considered to improve pedestrian safety. PMID:24357516
Evaluation of US rear underride guard regulation for large trucks using real-world crashes.
Brumbelow, Matthew L; Blanar, Laura
2010-11-01
Current requirements for rear underride guards on large trucks are set by the National Highway Traffic Safety Administration in Federal Motor Vehicle Safety Standards (FMVSS) 223 and 224. The standards have been in place since 1998, but their adequacy has not been evaluated apart from two series of controlled crash tests. The current study used detailed reviews of real-world crashes from the Large Truck Crash Causation Study to assess the ability of guards that comply with certain aspects of the regulation to mitigate passenger vehicle underride. It also evaluated the dangers posed by underride of large trucks that are exempt from guard requirements. For the 115 cases meeting the inclusion criteria, coded data, case narratives, photographs, and measurements were used to examine the interaction between study vehicles. The presence and type of underride guard was determined, and its performance in mitigating underride was categorized. Overall, almost one-half of the passenger vehicles had underride damage classified as severe or catastrophic. These vehicles accounted for 23 of the 28 in which occupants were killed. For the cases involving trailers with underride guards compliant with one or both FMVSS, guard deformation or complete failure was frequent and most commonly due to weak attachments, buckling of the trailer chassis, or bending of the lateral end of the guard under narrow overlap loading. Most of the truck units studied qualified for at least one of the FMVSS exemptions. The two largest groups were trailers with small wheel setbacks and single-unit straight trucks. Dump trucks represented a particularly hazardous category of straight truck. The current study suggests several weaknesses in the rear underride guard regulation. The standard allows too much ground clearance, the quasi-static test conditions allow guard designs that fail in narrow overlap crashes, and certifying guards independent of trailers leads to systems with inadequate attachment and chassis strength. Additionally, the regulation should be expanded to cover a higher percentage of the large truck fleet.
Kanbay's Global Leadership Development Program: A Case Study of Virtual Action Learning
ERIC Educational Resources Information Center
Marsh, Catherine; Johnson, Carrie
2005-01-01
This study examines action learning as a vehicle for the transfer of organizational values in a multi-cultural, virtual-team based leadership development process. A Case Study of Kanbay International's Global Leadership Development Program is used as a lens through which HRD researchers and practitioners may glimpse new possibilities for the…
Kou, Weibin; Chen, Xumei; Yu, Lei; Gong, Huibo
2018-04-18
Most existing signal timing models are aimed to minimize the total delay and stops at intersections, without considering environmental factors. This paper analyzes the trade-off between vehicle emissions and traffic efficiencies on the basis of field data. First, considering the different operating modes of cruising, acceleration, deceleration, and idling, field data of emissions and Global Positioning System (GPS) are collected to estimate emission rates for heavy-duty and light-duty vehicles. Second, multiobjective signal timing optimization model is established based on a genetic algorithm to minimize delay, stops, and emissions. Finally, a case study is conducted in Beijing. Nine scenarios are designed considering different weights of emission and traffic efficiency. The results compared with those using Highway Capacity Manual (HCM) 2010 show that signal timing optimized by the model proposed in this paper can decrease vehicles delay and emissions more significantly. The optimization model can be applied in different cities, which provides supports for eco-signal design and development. Vehicle emissions are heavily at signal intersections in urban area. The multiobjective signal timing optimization model is proposed considering the trade-off between vehicle emissions and traffic efficiencies on the basis of field data. The results indicate that signal timing optimized by the model proposed in this paper can decrease vehicle emissions and delays more significantly. The optimization model can be applied in different cities, which provides supports for eco-signal design and development.
Gackstetter, Gary D; Hooper, Tomoko I; DeBakey, Samar F; Johnson, Amy; Nagaraj, Barbara E; Heller, Jack M; Kang, Han K
2006-04-01
A proposed explanation for the observed higher risk of fatal motor vehicle crashes (MVC) among 1991 Gulf War-deployed veterans is neurocognitive deficits resulting from nerve agent exposure at Khamisiyah, Iraq. Our objective was to assess any association between postwar fatal MVC and possible nerve agent exposure based on 2000 modeled plume data. Cases were defined as MVC deaths with a record in the Department of Transportation Fatality Analysis Reporting System through 1995. Cases (n = 282) and controls (n = 3,131) were derived from a larger nested case-control study of Gulf War-era veterans and limited to Army, male, deployed personnel. Exposure and cumulative dose by case-control status were analyzed using multivariate techniques. Exposure status was not associated with fatal MVC (OR 0.96, 95% CI 0.72-1.26), nor were tertiles of cumulative dose. Findings do not support an association between possible exposures at Khamisiyah and postwar fatal MVC among Gulf War veterans.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mintz, Marianne; Tomich, Matthew
This case study explores the production and use of renewable compressed natural gas (R-CNG)—derived from the anaerobic digestion (AD) of organic waste—to fuel heavy-duty refuse trucks and other natural gas vehicles in Sacramento, California.
Ngallaba, S E; Majinge, C; Gilyoma, J; Makerere, D J; Charles, E
2013-06-01
Sixty percent of the global deaths and injuries occur in the developing world and mostly are due to Road traffic accidents (RTAs. looking at the etiological related factors which include, carelessness of the driver, condition of the vehicle or motorcycle, poor condition of roads, risky behavior of the driver, most of these factors can be prevented to some extent. This study therefore, determined the pattern of cases and deaths due to traffic road accidents in Mwanza City Tanzania. In this retrospective study, records, registers and case notes In the surgical ward and causality, medical records and central police station from 2008 to 2011 were used. The study focused on the two referral hospitals (Sekouture regional hospital and Bugando Medical Center). There were 3450 cases due to accidents reported at both centers (Sekouture regional hospital and Bugando Medical Center of which 3224 (93.4%) had complete information for analysis.2225 (69%) were male and 999 (31%) were female, and the most affected group were male. Among the RTAs2809 cases (87%) were due to motor cycle accidents which were the leading cause of RTAs with case fatality rate of 5% while motor vehicle has case fatality rate of 24% which is 5 times that of motor cycle. Among all RTAs the leading cause of injuries is Motor cycle traffic accidents followed by motor vehicle. RTAs are on increase particularly the motor cycle traffic accidents and has claimed a good number of innocent people's lives however most of them are preventable, therefore driving course to be introduced to motor cycle drivers with emphasize on the road posters signal, rules and regular checkup of their motor cycles especially commercial motor cycle.
Impact of Automation on Drivers' Performance in Agricultural Semi-Autonomous Vehicles.
Bashiri, B; Mann, D D
2015-04-01
Drivers' inadequate mental workload has been reported as one of the negative effects of driving assistant systems and in-vehicle automation. The increasing trend of automation in agricultural vehicles raises some concerns about drivers' mental workload in such vehicles. Thus, a human factors perspective is needed to identify the consequences of such automated systems. In this simulator study, the effects of vehicle steering task automation (VSTA) and implement control and monitoring task automation (ICMTA) were investigated using a tractor-air seeder system as a case study. Two performance parameters (reaction time and accuracy of actions) were measured to assess drivers' perceived mental workload. Experiments were conducted using the tractor driving simulator (TDS) located in the Agricultural Ergonomics Laboratory at the University of Manitoba. Study participants were university students with tractor driving experience. According to the results, reaction time and number of errors made by drivers both decreased as the automation level increased. Correlations were found among performance parameters and subjective mental workload reported by the drivers.
LaBan, Myron M; Nabity, Thomas S
2010-07-01
This study had its genesis in a personally observed collision between a motor vehicle and a motorized wheelchair (electric mobility device) on a busy street in the middle of the block at an unmarked crossing. To the observer, at the time, this appeared to be a suicidal act. This investigation was initiated to both delineate the number of these crashes nationally and understand this phenomena as a potentially planned act of self-destruction. An initial survey of police reports was immediately frustrated by an inability to separate motor vehicle and electric mobility device collisions from the much larger group that involved ambulatory citizens because both types were classified together as "pedestrian" accidents. Instead, the search engine NexisLexis was used to identify 107 newspaper articles each of which described a motor vehicle and electric mobility device accident. In the motor vehicle and electric mobility device collisions, men predominated women (3:1 ratio) with an average age of 56 yrs. Sixty of these accidents were fatal. Ninety-four percent involved an electric mobility device and 6% a manual wheelchair. In 50% of the cases, the motor vehicle was a truck, van, or sport utility vehicle. Fifty percent occurred at dusk or dawn or at night. The electric mobility device occupant was cited as the guilty party in 39% of the cases and the driver of the motor vehicle in 27%. Twenty percent were unwitnessed hit-and-run accidents, whereas "no fault" was found in 8% of the cases. Although many accidents do happen by chance, when an electric mobility device operator openly challenges busy traffic by attempting to traverse it in the middle of the block at an unmarked crossing, predisposing psychosocial factors must also be considered. Hubris or premeditated self-destructive behavior or both need to be explored as preeminent issues with reference to the prodromal of the "accident process."
Study on loading and unloading performance of new energy vehicle battery sensor
NASA Astrophysics Data System (ADS)
Wu, Bin; Ren, Kai; Liu, Ying
2017-04-01
This paper first introduces the 18650 battery, describes the importance of the battery temperature sensor, uses Ansys Workbench finite element simulation software and the mean of the combination of displacement constraint and reaction force, studies the force and the size of the change of new energy vehicle battery temperature sensor in the loading, translation and unloading of the three cases, then make the test to verify its accuracy. At last, the test results are compared with the usual maximum acceleration of the vehicle in driving which verified the sensor of the car will not fall off in the car driving process and work normally.
An important factor in evaluating health risk of near-road air pollution is to accurately estimate the traffic-related vehicle emission of air pollutants. Inclusion of traffic parameters such as road length/area, distance to roads, and traffic volume/intensity into models such as...
Private forest landowner attitudes toward off-highway vehicle access: A Minnesota case study
Dennis R. Becker; Grant L. Wilson; Stephanie A. Snyder
2010-01-01
Off-highway vehicle (OHV) riding has increased dramatically in the past decade, creating challenges for finding suitable places to ride, particularly where access to public lands is limited. This research examines the attitudes and willingness of private forest and seasonal recreation landowners to provide OHV access. A series of focus groups was conducted to inform a...
Vehicular Integration of Wireless Power Transfer Systems and Hardware Interoperability Case Studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Onar, Omer C; Campbell, Steven L; Seiber, Larry Eugene
Several wireless charging methods are under development or available as an aftermarket option in the light-duty automotive market. However, there are not a sufficient number of studies detailing the vehicle integration methods, particularly a complete vehicle integration with higher power levels. This paper presents the design, development, implementation, and vehicle integration of wireless power transfer (WPT)-based electric vehicle (EV) charging systems for various test vehicles. Before having the standards effective, it is expected that WPT technology first will be integrated as an aftermarket retrofitting approach. Inclusion of this technology on production vehicles is contingent upon the release of the internationalmore » standards. The power stages of the system are introduced with the design specifications and control systems including the active front-end rectifier with power factor correction, high frequency power inverter, high frequency isolation transformer, coupling coils, vehicle side full-bridge rectifier and filter, and the vehicle battery. The operating principles of the control, and communications, systems are presented. Aftermarket conversion approaches including the WPT on-board charger (OBC) integration, WPT CHAdeMO integration, and WPT direct battery connection scenarios are described. The experiments are carried out using the integrated vehicles and the results obtained to demonstrate the system performance including the stage-by-stage efficiencies.« less
Unmanned vehicles for maritime spill response case study: Exercise Cathach.
Dooly, Gerard; Omerdic, Edin; Coleman, Joseph; Miller, Liam; Kaknjo, Admir; Hayes, James; Braga, Jóse; Ferreira, Filipe; Conlon, Hugh; Barry, Hugh; Marcos-Olaya, Jesús; Tuohy, Thomas; Sousa, João; Toal, Dan
2016-09-15
This paper deals with two aspects, namely a historical analysis of the use of unmanned vehicles (UAVs ROVs, AUVs) in maritime spill incidents and a detailed description of a multi-agency oil and HNS incident response exercise involving the integration and analysis of unmanned vehicles environmental sensing equipment. The exercise was a first in terms of the level of robotic systems deployed to assist in survey, surveillance and inspection roles for oil spills and harmful and noxious substances. Copyright © 2016 Elsevier Ltd. All rights reserved.
Nowakowski, Piotr
2017-02-01
Waste electrical and electronic equipment (WEEE), also known as e-waste, is one of the most important waste streams with high recycling potential. Materials used in these products are valuable, but some of them are hazardous. The urban mining approach attempts to recycle as many materials as possible, so efficiency in collection is vital. There are two main methods used to collect WEEE: stationary and mobile, each with different variants. The responsibility of WEEE organizations and waste collection companies is to assure all resources required for these activities - bins, containers, collection vehicles and staff - are available, taking into account cost minimization. Therefore, it is necessary to correctly determine the capacity of containers and number of collection vehicles for an area where WEEE need to be collected. There are two main problems encountered in collection, storage and transportation of WEEE: container loading problems and vehicle routing problems. In this study, an adaptation of these two models for packing and collecting WEEE is proposed, along with a practical implementation plan designed to be useful for collection companies' guidelines for container loading and route optimization. The solutions are presented in the case studies of real-world conditions for WEEE collection companies in Poland. Copyright © 2016 Elsevier Ltd. All rights reserved.
Network modeling for reverse flows of end-of-life vehicles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ene, Seval; Öztürk, Nursel
2015-04-15
Highlights: • We developed a network model for reverse flows of end-of-life vehicles. • The model considers all recovery operations for end-of-life vehicles. • A scenario-based model is used for uncertainty to improve real case applications. • The model is adequate to real case applications for end-of-life vehicles recovery. • Considerable insights are gained from the model by sensitivity analyses. - Abstract: Product recovery operations are of critical importance for the automotive industry in complying with environmental regulations concerning end-of-life products management. Manufacturers must take responsibility for their products over the entire life cycle. In this context, there is amore » need for network design methods for effectively managing recovery operations and waste. The purpose of this study is to develop a mathematical programming model for managing reverse flows in end-of-life vehicles’ recovery network. A reverse flow is the collection of used products from consumers and the transportation of these products for the purpose of recycling, reuse or disposal. The proposed model includes all operations in a product recovery and waste management network for used vehicles and reuse for vehicle parts such as collection, disassembly, refurbishing, processing (shredding), recycling, disposal and reuse of vehicle parts. The scope of the network model is to determine the numbers and locations of facilities in the network and the material flows between these facilities. The results show the performance of the model and its applicability for use in the planning of recovery operations in the automotive industry. The main objective of recovery and waste management is to maximize revenue and minimize pollution in end-of-life product operations. This study shows that with an accurate model, these activities may provide economic benefits and incentives in addition to protecting the environment.« less
An Accurate and Generic Testing Approach to Vehicle Stability Parameters Based on GPS and INS.
Miao, Zhibin; Zhang, Hongtian; Zhang, Jinzhu
2015-12-04
With the development of the vehicle industry, controlling stability has become more and more important. Techniques of evaluating vehicle stability are in high demand. As a common method, usually GPS sensors and INS sensors are applied to measure vehicle stability parameters by fusing data from the two system sensors. Although prior model parameters should be recognized in a Kalman filter, it is usually used to fuse data from multi-sensors. In this paper, a robust, intelligent and precise method to the measurement of vehicle stability is proposed. First, a fuzzy interpolation method is proposed, along with a four-wheel vehicle dynamic model. Second, a two-stage Kalman filter, which fuses the data from GPS and INS, is established. Next, this approach is applied to a case study vehicle to measure yaw rate and sideslip angle. The results show the advantages of the approach. Finally, a simulation and real experiment is made to verify the advantages of this approach. The experimental results showed the merits of this method for measuring vehicle stability, and the approach can meet the design requirements of a vehicle stability controller.
Air Force Organizational Adoption of Remotely Piloted Vehicles
2004-05-01
organization that employs them. On the other hand, disruptive technologies are consistent with RMAs, eliminating a fundamental ability that provides...the idea of sustaining and disruptive technologies . An extensive case study of the disk drive industry details some key but often overlooked...characteristics of disruptive technology. A total of 116 cases of new technologies were studied with four of the cases involving disruptive technologies . In
Arregui-Dalmases, Carlos; Rebollo-Soria, M Carmen; Sanchez-Molina, David; Velazquez-Ameijide, Juan; Teijeira Alvarez
Pedestrian-vehicle collisions are a leading cause of death among motor vehicle accidents. Recently, pedestrian injury research has been increased, mostly due to the implementation of European and Japanese regulations. This research presents an analysis of the main head injury vehicle sources and injury mechanisms observed in the field, posteriorly the data are compared with the current pedestrian regulations. The analysis has been performed through an epidemiologic transversal and descriptive study, using the Pedestrian Crash Data Study (PCDS) involving 552 pedestrians, sustaining a total of 4.500 documented injuries. According to this research, the hood surface is responsible for only 15,1% of all the head injuries. On the other hand, the windshield glazing is responsible for 41,8%. In case of sedan vehicles the head impact location exceeds what is expected in the current regulation, and therefore no countermeasures are applied. From all the head injuries sustained by the pedestrians just 20% have the linear acceleration as isolated injury mechanism, 40% of the injuries are due to rotational acceleration. In this research, the importance of the rotational acceleration as injury mechanism, in case of pedestrian-vehicle collision is highlighted. In the current pedestrian regulation just the linear acceleration is addressed in the main injury criteria used for head injury prediction. Copyright © 2016 Sociedad Española de Neurocirugía. Publicado por Elsevier España, S.L.U. All rights reserved.
Watzek, Nico; Berger, Franz; Kolle, Susanne Noreen; Kaufmann, Tanja; Becker, Matthias; van Ravenzwaay, Bennard
2017-04-01
In the EU, chemicals with a production or import volume in quantities of one metric ton per year or more have to be tested for skin sensitizing properties under the REACH regulation. The murine Local Lymph Node Assay (LLNA) and its modifications are widely used to fulfil the data requirement, as it is currently considered the first-choice method for in vivo testing to cover this endpoint. This manuscript describes a case study highlighting the importance of understanding the chemistry of the test material during testing for 'skin sensitization' of MCDA (mixture of 2,4- and 2,6-diamino-methylcyclohexane) with particular focus on the vehicle used. While the BrdU-ELISA modification of the LLNA using acetone/olive oil (AOO) as vehicle revealed expectable positive results. However, the concentration control analysis unexpectedly revealed an instability of MCDA in the vehicle AOO. Further studies on the reactivity showed MCDA to rapidly react with AOO under formation of various imine structures, which might have caused the positive LLNA result. The repetition of the LLNA using propylene glycol (PG) as vehicle did not confirm the positive results of the LLNA using AOO. Finally, a classification of MCDA as skin sensitizer according to the Globally Harmonized System (GHS) was not justified. Copyright © 2017 Elsevier Inc. All rights reserved.
Car crash fatalities associated with fire in Sweden.
Viklund, Åsa; Björnstig, Johanna; Larsson, Magnus; Björnstig, Ulf
2013-01-01
To study the epidemiology and causes of death in fatal car crashes on Swedish roads in which the victim's vehicle caught fire. The data set is from the Swedish Transport Administrations in-depth studies of fatal crashes 1998-2008. Autopsies from all cases provided data on injuries, toxicological analyses, and cause of death. In total, 181 people died in 133 burning cars, accounting for 5 percent of all deaths in passenger cars, sport utility vehicles, vans, and minibuses during 1998 to 2008. The cause of death for a third of the victims was fire related, as burns and/or smoke inhalation injuries, with no fatal trauma injuries. Twenty-five of these 55 deaths were persons 19 years or younger and included 15 of 18 rear seat deaths. Over half of the 181 deaths were in vehicles that had collided with another vehicle and, of these cases, half were killed in collisions with heavy vehicles. The percentage of drivers with illegal blood alcohol concentrations (27%) and suicides (5.5%) were not higher than in other fatal crashes on Swedish roads. The ignition point of the fire was indicated in only half of the cases and, of those, half started in the engine compartment and one fourth started around the fuel tank or lines. Car fires are a deadly postcrash problem. Reducing this risk would be primarily a responsibility for the automotive industry. A multifactor approach could be considered as follows: risk-reducing design, insulation, reduced flammability in motor compartment fluids and plastics, and automatic fire extinguishing equipment. Inspiration could be found in how, for example, the auto racing and aviation industries handle this problem.
NASA Astrophysics Data System (ADS)
Zhang, Shaojun; Wu, Ye; Huang, Ruikun; Wang, Jiandong; Yan, Han; Zheng, Yali; Hao, Jiming
2016-08-01
Vehicle emissions containing air pollutants created substantial environmental impacts on air quality for many traffic-populated cities in eastern Asia. A high-resolution emission inventory is a useful tool compared with traditional tools (e.g. registration data-based approach) to accurately evaluate real-world traffic dynamics and their environmental burden. In this study, Macau, one of the most populated cities in the world, is selected to demonstrate a high-resolution simulation of vehicular emissions and their contribution to air pollutant concentrations by coupling multimodels. First, traffic volumes by vehicle category on 47 typical roads were investigated during weekdays in 2010 and further applied in a networking demand simulation with the TransCAD model to establish hourly profiles of link-level vehicle counts. Local vehicle driving speed and vehicle age distribution data were also collected in Macau. Second, based on a localized vehicle emission model (e.g. the emission factor model for the Beijing vehicle fleet - Macau, EMBEV-Macau), this study established a link-based vehicle emission inventory in Macau with high resolution meshed in a temporal and spatial framework. Furthermore, we employed the AERMOD (AMS/EPA Regulatory Model) model to map concentrations of CO and primary PM2.5 contributed by local vehicle emissions during weekdays in November 2010. This study has discerned the strong impact of traffic flow dynamics on the temporal and spatial patterns of vehicle emissions, such as a geographic discrepancy of spatial allocation up to 26 % between THC and PM2.5 emissions owing to spatially heterogeneous vehicle-use intensity between motorcycles and diesel fleets. We also identified that the estimated CO2 emissions from gasoline vehicles agreed well with the statistical fuel consumption in Macau. Therefore, this paper provides a case study and a solid framework for developing high-resolution environment assessment tools for other vehicle-populated cities in eastern Asia.
A cost engineered launch vehicle for space tourism
NASA Astrophysics Data System (ADS)
Koelle, -Ing. Dietrich E., , Dr.
1999-09-01
The paper starts with a set of major requirements for a space tourism vehicle and discusses major vehicle options proposed for this purpose. It seems that the requirements can be met best with a Ballistic SSTO Vehicle which has the additional advantage of lowest development cost compared to other launch vehicle options — important for a commercial development venture. The BETA Ballistic Reusable Vehicle Concept is characterized by the plug nozzle cluster engine configuration where the plug nozzle serves also as base plate and re-entry heat shield. In this case no athmospheric turn maneuver is required (as in case-of the front-entry Delta-Clipper DC-Y concept). In our specific case for space tourism this mode has the avantage that the forces at launch and reentry are in exactly the same direction, easing passenger seating arrangements. The second basic advantage is the large available volume on top of the vehicle providing ample space for passenger accomodation, visibility and volume for zero-g experience (free floating), one of the major passenger mission requirements. An adequate passenger cabin design for 100 passengers is presented, as well as the modern BETA-STV Concept with its mass allocations.
Investigation of crew performance in a multi-vehicle supervisory control task
NASA Technical Reports Server (NTRS)
Miller, R. A.; Plamondon, B. D.; Jagacinski, R. J.; Kirlik, A. C.
1986-01-01
Crew information processing and decision making in a supervisory control task which is loosely based on the mission of future generation helicopters is measured and represented. Subjects control the motion and activities of their own vehicle and direct the activities of four additional craft. The task involves searching an uncertain environment for cargo and enemies, returning cargo to home base and destroying enemies while attempting to avoid destruction of the scout and the supervised vehicles. A series of experiments with two-person crews and one-person crews were performed. Resulting crew performance was modeled with the objective of describing and understanding the information processing strategies utilized. Of particular interest are problem simplification strategies under time stress and high work load, simplification and compensation in the one-person cases, crew coordination in the two-person cases, and the relationship between strategy and errors in all cases. The results should provide some insight into the effective use of aids, particularly aids based on artificial intelligence, for similar tasks. The simulation is described which is used for the study and some preliminary results from the first two-person crew study are discussed.
Papp, K; Poulin, Y; Barber, K; Lynde, C; Prinz, J C; Berg, M; Kerrouche, N; Rives, V P
2012-11-01
Scalp psoriasis is a difficult to treat and usually chronic manifestation of psoriasis. The CalePso study showed that CPS (Clobex(®) Shampoo) in maintenance therapy of scalp psoriasis (twice weekly) significantly increases the probability of keeping patient under remission during 6 months, compared with vehicle (40.3% relapses vs. 11.6% relapses, ITT). The objective of the study was to assess the cost-effectiveness of a maintenance therapy with CPS vs. its vehicle in nine European countries. A 24-week decision tree model was developed with 4-weekly time steps. The considered population has moderate scalp psoriasis successfully treated with a daily application of CPS up to 4 weeks. Data were taken from the CalePso study and from national experts' recommendations for alternative treatment choices, with their probabilities of success taken from literature to develop country-specific models. Health benefits are measured in disease-free days (DFD). The economic analysis includes drug and physician costs. A probabilistic sensitivity analysis (PrSA) assesses the uncertainty of the model. Depending on the country, the mean total number of DFDs per patient is 21-42% higher with CPS compared with vehicle, and the mean total cost is 11-31% lower. The mean costs per DFD are 30-46% lower with CPS compared with the vehicle. The PrSA showed in 1000 simulations that CPS is more effective vs. vehicle in 100% of the cases and less expensive than its vehicle in 80-99% of the cases. This model suggests that CPS is cost-effective in maintaining the success achieved in moderate scalp psoriasis patients. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.
NASA Astrophysics Data System (ADS)
Zhang, Guoguang; Yu, Zitian; Wang, Junmin
2017-03-01
Yaw rate is a crucial signal for the motion control systems of ground vehicles. Yet it may be contaminated by sensor bias. In order to correct the contaminated yaw rate signal and estimate the sensor bias, a robust gain-scheduling observer is proposed in this paper. First of all, a two-degree-of-freedom (2DOF) vehicle lateral and yaw dynamic model is presented, and then a Luenberger-like observer is proposed. To make the observer more applicable to real vehicle driving operations, a 2DOF vehicle model with uncertainties on the coefficients of tire cornering stiffness is employed. Further, a gain-scheduling approach and a robustness enhancement are introduced, leading to a robust gain-scheduling observer. Sensor bias detection mechanism is also designed. Case studies are conducted using an electric ground vehicle to assess the performance of signal correction and sensor bias estimation under difference scenarios.
Ares-I-X Vehicle Preliminary Range Safety Malfunction Turn Analysis
NASA Technical Reports Server (NTRS)
Beaty, James R.; Starr, Brett R.; Gowan, John W., Jr.
2008-01-01
Ares-I-X is the designation given to the flight test version of the Ares-I rocket (also known as the Crew Launch Vehicle - CLV) being developed by NASA. As part of the preliminary flight plan approval process for the test vehicle, a range safety malfunction turn analysis was performed to support the launch area risk assessment and vehicle destruct criteria development processes. Several vehicle failure scenarios were identified which could cause the vehicle trajectory to deviate from its normal flight path, and the effects of these failures were evaluated with an Ares-I-X 6 degrees-of-freedom (6-DOF) digital simulation, using the Program to Optimize Simulated Trajectories Version 2 (POST2) simulation framework. The Ares-I-X simulation analysis provides output files containing vehicle state information, which are used by other risk assessment and vehicle debris trajectory simulation tools to determine the risk to personnel and facilities in the vicinity of the launch area at Kennedy Space Center (KSC), and to develop the vehicle destruct criteria used by the flight test range safety officer. The simulation analysis approach used for this study is described, including descriptions of the failure modes which were considered and the underlying assumptions and ground rules of the study, and preliminary results are presented, determined by analysis of the trajectory deviation of the failure cases, compared with the expected vehicle trajectory.
International outbreak investigation of Salmonella Heidelberg associated with in-flight catering.
Rebolledo, J; Garvey, P; Ryan, A; O'Donnell, J; Cormican, M; Jackson, S; Cloak, F; Cullen, L; Swaan, C M; Schimmer, B; Appels, R W; Nygard, K; Finley, R; Sreenivasan, N; Lenglet, A; Gossner, C; McKeown, P
2014-04-01
Rapid and wide dispersal of passengers after flights makes investigation of flight-related outbreaks challenging. An outbreak of Salmonella Heidelberg was identified in a group of Irish travellers returning from Tanzania. Additional international cases sharing the same flight were identified. Our aim was to determine the source and potential vehicles of infection. Case-finding utilized information exchange using experts' communication networks and national surveillance systems. Demographic, clinical and food history information was collected. Twenty-five additional cases were identified from Ireland, The Netherlands, Norway, USA and Canada. We conducted a case-control study which indicated a significant association between illness and consumption of milk tart (OR 10.2) and an egg dish (OR 6) served on-board the flight. No food consumed before the flight was associated with illness. Cases from countries other than Ireland provided supplementary information that facilitated the identification of likely vehicles of infection. Timely, committed international collaboration is vital in such investigations.
Impact of electric vehicles on the IEEE 34 node distribution infrastructure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, Zeming; Shalalfel, Laith; Beshir, Mohammed J.
With the growing penetration of the electric vehicles to our daily life owing to their economic and environmental benefits, there will be both opportunities and challenges to the utilities when adopting plug-in electric vehicles (PEV) to the distribution network. In this study, a thorough analysis based on real-world project is conducted to evaluate the impacts of electric vehicles infrastructure on the grid relating to system load flow, load factor, and voltage stability. IEEE 34 node test feeder was selected and tested along with different case scenarios utilizing the electrical distribution design (EDD) software to find out the potential impacts tomore » the grid.« less
Impact of electric vehicles on the IEEE 34 node distribution infrastructure
Jiang, Zeming; Shalalfel, Laith; Beshir, Mohammed J.
2014-10-01
With the growing penetration of the electric vehicles to our daily life owing to their economic and environmental benefits, there will be both opportunities and challenges to the utilities when adopting plug-in electric vehicles (PEV) to the distribution network. In this study, a thorough analysis based on real-world project is conducted to evaluate the impacts of electric vehicles infrastructure on the grid relating to system load flow, load factor, and voltage stability. IEEE 34 node test feeder was selected and tested along with different case scenarios utilizing the electrical distribution design (EDD) software to find out the potential impacts tomore » the grid.« less
NASA Astrophysics Data System (ADS)
Chen, Xinyu; Zhang, Hongcai; Xu, Zhiwei; Nielsen, Chris P.; McElroy, Michael B.; Lv, Jiajun
2018-05-01
Current Chinese policy promotes the development of both electricity-propelled vehicles and carbon-free sources of power. Concern has been expressed that electric vehicles on average may emit more CO2 and conventional pollutants in China. Here, we explore the environmental implications of investments in different types of electric vehicle (public buses, taxis and private light-duty vehicles) and different modes (fast or slow) for charging under a range of different wind penetration levels. To do this, we take Beijing in 2020 as a case study and employ hourly simulation of vehicle charging behaviour and power system operation. Assuming the slow-charging option, we find that investments in electric private light-duty vehicles can result in an effective reduction in the emission of CO2 at several levels of wind penetration. The fast-charging option, however, is counter-productive. Electrifying buses and taxis offers the most effective option to reduce emissions of NOx, a major precursor for air pollution.
Simulating the value of electric-vehicle-grid integration using a behaviourally realistic model
NASA Astrophysics Data System (ADS)
Wolinetz, Michael; Axsen, Jonn; Peters, Jotham; Crawford, Curran
2018-02-01
Vehicle-grid integration (VGI) uses the interaction between electric vehicles and the electrical grid to provide benefits that may include reducing the cost of using intermittent renwable electricity or providing a financial incentive for electric vehicle ownerhip. However, studies that estimate the value of VGI benefits have largely ignored how consumer behaviour will affect the magnitude of the impact. Here, we simulate the long-term impact of VGI using behaviourally realistic and empirically derived models of vehicle adoption and charging combined with an electricity system model. We focus on the case where a central entity manages the charging rate and timing for participating electric vehicles. VGI is found not to increase the adoption of electric vehicles, but does have a a small beneficial impact on electricity prices. By 2050, VGI reduces wholesale electricity prices by 0.6-0.7% (0.7 MWh-1, 2010 CAD) relative to an equivalent scenario without VGI. Excluding consumer behaviour from the analysis inflates the value of VGI.
Meuleners, Lynn; Fraser, Michelle L; Govorko, Matthew H; Stevenson, Mark R
2017-02-01
To determine the association between a heavy vehicle driver's work environment, including fatigue-related characteristics, and the risk of a crash in Western Australia. This case-control study included 100 long-haul heavy vehicle drivers who were involved in a police-reported crash in WA and 100 long-haul heavy vehicle drivers recruited from WA truck stops, who were not involved in a crash in the previous 12 months. Driver demographics and driving details, work environment, vehicle and sleep-related characteristics were obtained using an interviewer-administered questionnaire. Drivers were tested for obstructive sleep apnoea using an overnight diagnostic device. Conditional multiple logistic regression analysis was undertaken to determine work environment-related factors associated with crash involvement. After accounting for potential confounders, driving a heavy vehicle with an empty load was associated with almost a three-fold increased crash risk compared to carrying general freight (adjusted OR: 2.93, 95% CI: 1.17-7.34). Driving a rigid heavy vehicle was associated with a four-fold increased risk of crashing compared to articulated heavy vehicles (adjusted OR: 4.08, 95% CI: 1.13-14.68). The risk of crashing was almost five times higher when driving more than 50% of the trip between midnight and 5.59am (adjusted OR: 4.86, 95% CI: 1.47-16.07). Furthermore, the risk of crashing significantly increased if the time since the last break on the index trip was greater than 2h (adjusted OR: 2.18, 95% CI: 1.14-4.17). Drivers with more than 10 years driving experience were 52% less likely to be involved in a crash (adjusted OR: 0.48, 95% CI: 0.23-0.99). The results provide support for an association between a driver's work environment, fatigue-related factors, and the risk of heavy vehicle crash involvement. Greater attention needs to be paid to the creation of a safer work environment for long distance heavy vehicle drivers. Copyright © 2015 Elsevier Ltd. All rights reserved.
Morgan, Richard M; Cui, Chongzhen; Digges, Kennerly H; Cao, Libo; Kan, Cing-Dao Steve
2012-01-01
This research investigated (1) what are the key attributes of the between-rail, frontal crash, (2) what are the types of object contacted, and (3) what is the type of resulting trauma. The method was to study with both weighted and in-depth case reviews of NASS-CDS crash data with direct damage between the longitudinal rails in frontal crashes. Individual case selection was limited to belted occupants in between-rail, frontal impacts of good-rated, late-model vehicles equipped with air bags.This paper evaluates the risk of trauma for drivers in cars and LTVs in between-rail, frontal crashes, and suggests the between-rail impact is more dangerous to car drivers. Using weighted data-representing 227,305 tow-away crashes-the resulting trauma to various body regions was analyzed to suggest greatest injury is to the chest, pelvis/thigh/knee/leg, and foot/ankle. This study analyzed the type of object that caused the direct damage between the rails, including small tree or post, large tree or pole, and another vehicle; and found that the struck object was most often another vehicle or a large tree/pole. Both the extent of damage and the occupant compartment intrusion were explored, and suggest that 64% of the serious injuries are associated with increasing intrusion. Individual NASS cases were reviewed to gain a deeper understanding of the mechanical particulars in the between-rail crash.
Morgan, Richard M.; Cui, Chongzhen; Digges, Kennerly H.; Cao, Libo; Kan, Cing-Dao (Steve)
2012-01-01
This research investigated (1) what are the key attributes of the between-rail, frontal crash, (2) what are the types of object contacted, and (3) what is the type of resulting trauma. The method was to study with both weighted and in-depth case reviews of NASS-CDS crash data with direct damage between the longitudinal rails in frontal crashes. Individual case selection was limited to belted occupants in between-rail, frontal impacts of good-rated, late-model vehicles equipped with air bags. This paper evaluates the risk of trauma for drivers in cars and LTVs in between-rail, frontal crashes, and suggests the between-rail impact is more dangerous to car drivers. Using weighted data—representing 227,305 tow-away crashes—the resulting trauma to various body regions was analyzed to suggest greatest injury is to the chest, pelvis/thigh/knee/leg, and foot/ankle. This study analyzed the type of object that caused the direct damage between the rails, including small tree or post, large tree or pole, and another vehicle; and found that the struck object was most often another vehicle or a large tree/pole. Both the extent of damage and the occupant compartment intrusion were explored, and suggest that 64% of the serious injuries are associated with increasing intrusion. Individual NASS cases were reviewed to gain a deeper understanding of the mechanical particulars in the between-rail crash. PMID:23169135
Evaluating opportunities to improve material and energy impacts in commodity supply chains
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanes, Rebecca J.; Carpenter, Alberta
When evaluated at the scale of individual processes, next-generation technologies may be more energy and emissions intensive than current technology. Furthermore, many advanced technologies have the potential to reduce material and energy consumption in upstream or downstream processing stages. In order to fully understand the benefits and consequences of technology deployment, next-generation technologies should be evaluated in context, as part of a supply chain. This work presents the Materials Flow through Industry (MFI) supply chain modeling tool. The MFI tool is a cradle-to-gate linear network model of the US industrial sector that can model a wide range of manufacturing scenarios,more » including changes in production technology and increases in industrial energy efficiency. The MFI tool was developed to perform supply chain scale analyses in order to quantify the impacts and benefits of next-generation technologies and materials at that scale. For the analysis presented in this paper, the MFI tool is utilized to explore a case study comparing three lightweight vehicle supply chains to the supply chain of a conventional, standard weight vehicle. Several of the lightweight vehicle supply chains are evaluated under manufacturing scenarios that include next-generation production technologies and next-generation materials. Results indicate that producing lightweight vehicles is more energy and emission intensive than producing the non-lightweight vehicle, but the fuel saved during vehicle use offsets this increase. In this case study, greater reductions in supply chain energy and emissions were achieved through the application of the next-generation technologies than from application of energy efficiency increases.« less
Evaluating opportunities to improve material and energy impacts in commodity supply chains
Hanes, Rebecca J.; Carpenter, Alberta
2017-01-10
When evaluated at the scale of individual processes, next-generation technologies may be more energy and emissions intensive than current technology. Furthermore, many advanced technologies have the potential to reduce material and energy consumption in upstream or downstream processing stages. In order to fully understand the benefits and consequences of technology deployment, next-generation technologies should be evaluated in context, as part of a supply chain. This work presents the Materials Flow through Industry (MFI) supply chain modeling tool. The MFI tool is a cradle-to-gate linear network model of the US industrial sector that can model a wide range of manufacturing scenarios,more » including changes in production technology and increases in industrial energy efficiency. The MFI tool was developed to perform supply chain scale analyses in order to quantify the impacts and benefits of next-generation technologies and materials at that scale. For the analysis presented in this paper, the MFI tool is utilized to explore a case study comparing three lightweight vehicle supply chains to the supply chain of a conventional, standard weight vehicle. Several of the lightweight vehicle supply chains are evaluated under manufacturing scenarios that include next-generation production technologies and next-generation materials. Results indicate that producing lightweight vehicles is more energy and emission intensive than producing the non-lightweight vehicle, but the fuel saved during vehicle use offsets this increase. In this case study, greater reductions in supply chain energy and emissions were achieved through the application of the next-generation technologies than from application of energy efficiency increases.« less
Driver dependent factors and the risk of causing a collision for two wheeled motor vehicles
Lardelli-Claret, P; Jimenez-Moleon, J; de Dios, Luna-del-... J; Garcia-Martin, M; Bueno-Cavanillas, A; Galvez-Vargas, R
2005-01-01
Objective: To assess the effect of driver dependent factors on the risk of causing a collision for two wheeled motor vehicles (TWMVs). Design: Case control study. Setting: Spain, from 1993 to 2002. Subjects: All drivers of TWMVs involved in the 181 551 collisions between two vehicles recorded in the Spanish registry which did not involve pedestrians, and in which at least one of the vehicles was a TWMV and only one driver had committed a driving infraction. The infractor and non-infractor drivers constituted the case and control groups, respectively. Main outcome measures: Logistic regression analyses were used to obtain crude and adjusted odds ratio estimates for each of the driver related factors recorded in the registry (age, sex, nationality, psychophysical factors, and speeding infractions, among others). Results: Inappropriate speed was the variable with the greatest influence on the risk of causing a collision, followed by excessive speed and driving under the influence of alcohol. Younger and older drivers, foreign drivers, and driving without a valid license were also associated with a higher risk of causing a collision. In contrast, helmet use, female sex, and longer time in possession of a driving license were associated with a lower risk. Conclusions: Although the main driver dependent factors related to the risk of causing a collision for a TWMV were similar to those documented for four wheeled vehicles, several differences in the pattern of associations support the need to study moped and motorcycle crashes separately from crashes involving other types of vehicles. PMID:16081752
Son, Le Hoang; Louati, Amal
2016-06-01
Municipal Solid Waste (MSW) collection is a necessary process in any municipality resulting in the quality-of-life, economic aspects and urban structuralization. The intrinsic nature of MSW collection relates to the development of effective vehicle routing models that optimize the total traveling distances of vehicles, the environmental emission and the investment costs. In this article, we propose a generalized vehicle routing model including multiple transfer stations, gather sites and inhomogeneous vehicles in time windows for MSW collection. It takes into account traveling in one-way routes, the number of vehicles per m(2) and waiting time at traffic stops for reduction of operational time. The proposed model could be used for scenarios having similar node structures and vehicles' characteristics. A case study at Danang city, Vietnam is given to illustrate the applicability of this model. The experimental results have clearly shown that the new model reduces both total traveling distances and operational hours of vehicles in comparison with those of practical scenarios. Optimal routes of vehicles on streets and markets at Danang are given. Those results are significant to practitioners and local policy makers. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wainiqolo, Iris; Kafoa, Berlin; Kool, Bridget; Robinson, Elizabeth; Herman, Josephine; McCaig, Eddie; Ameratunga, Shanthi
2016-01-01
Objective To investigate the association between kava use and the risk of four-wheeled motor vehicle crashes in Fiji. Kava is a traditional beverage commonly consumed in many Pacific Island Countries. Herbal anxiolytics containing smaller doses of kava are more widely available. Methods Data for this population-based case-control study were collected from drivers of ‘case’ vehicles involved in serious injury-involved crashes (where at least one road user was killed or admitted to hospital for 12 hours or more) and ‘control’ vehicles representative of ‘driving time’ in the study base. Structured interviewer administered questionnaires collected self-reported participant data on demographic characteristics and a range of risk factors including kava use and potential confounders. Unconditional logistic regression models estimated odds ratios relating to the association between kava use and injury-involved crash risk. Findings Overall, 23% and 4% of drivers of case and control vehicles, respectively, reported consuming kava in the 12 hours prior to the crash or road survey. After controlling for assessed confounders, driving following kava use was associated with a four-fold increase in the odds of crash involvement (Odds ratio: 4.70; 95% CI: 1.90–11.63). The related population attributable risk was 18.37% (95% CI: 13.77–22.72). Acknowledging limited statistical power, we did not find a significant interaction in this association with concurrent alcohol use. Conclusion In this study conducted in a setting where recreational kava consumption is common, driving following the use of kava was associated with a significant excess of serious-injury involved road crashes. The precautionary principle would suggest road safety strategies should explicitly recommend avoiding driving following kava use, particularly in communities where recreational use is common. PMID:26930404
Guard, A; Gallagher, S
2005-01-01
Objective: To describe the circumstances surrounding heat related deaths to young children in passenger compartments of motor vehicles. Methods: Cases of heat related deaths to children aged ⩽5 years confined in parked vehicles were retrospectively identified using online news accounts from 1 January 1995 to 31 December 2002. A standardized data form was developed to collect information related to the victim, the vehicle and its design features, external temperature, length of time confined, and the responsible adults. Cases were categorized by whether the child gained access to the vehicle or was left by adults. Results: A total of 171 fatalities that met the case criteria were identified. Twenty seven percent (46) were children who gained access to unlocked vehicles and 73% (125) were children who were left by adults. More than a quarter of the adults were aware they were leaving children in the vehicles, while half were unaware or forgot. Forty three percent (54) of deaths to children who were left were associated with childcare: 32 children were left by family members who intended to take them to childcare but forgot and went to work instead; 22 children were left by child care providers or drivers. Conclusions: Many of the deaths reported in this study may have been prevented by keeping cars locked, educating parents, implementing informed child care transportation policies, passing relevant laws, and working with auto and child safety seat manufacturers to build in warnings and other design features. News sources can be useful for obtaining detailed information not otherwise identifiable through standard sources of fatality data. PMID:15691987
Ares Launch Vehicles Lean Practices Case Study
NASA Technical Reports Server (NTRS)
Doreswamy, Rajiv, N.; Self, Timothy A.
2008-01-01
This viewgraph presentation describes test strategies and lean philisophies and practices that are applied to Ares Launch Vehicles. The topics include: 1) Testing strategy; 2) Lean Practices in Ares I-X; 3) Lean Practices Applied to Ares I-X Schedule; 4) Lean Event Results; 5) Lean, Six Sigma, and Kaizen Practices in the Ares Projects Office; 6) Lean and Kaizen Success Stories; and 7) Ares Six Sigma Practices.
ERIC Educational Resources Information Center
Cartney, Patricia
2010-01-01
The literature is increasingly drawing attention to the gap between feedback "given" to students and feedback "used" by students. This paper reflects on the beginnings of an evaluation into the potential of peer assessment to act as a vehicle to enable students to make use of the feedback they receive. A case study is presented…
Mine-Resistant Ambush-Protection vehicles
2014-02-13
CAPE CANAVERAL, Fla. – One of four new emergency egress vehicles, called Mine-Resistant Ambush-Protection, or MRAP, vehicles sits near space shuttle-era M-113 vehicles at the Maintenance and Operations Facility at NASA’s Kennedy Space Center in Florida. The MRAPs arrived from the U.S. Army Red River Depot in Texarkana, Texas in December 2013. The vehicles were processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Kim Shiflett
DOE Office of Scientific and Technical Information (OSTI.GOV)
Melaina, M.; Bremson, J.; Solo, K.
2013-01-01
The availability of retail stations can be a significant barrier to the adoption of alternative fuel light-duty vehicles in household markets. This is especially the case during early market growth when retail stations are likely to be sparse and when vehicles are dedicated in the sense that they can only be fuelled with a new alternative fuel. For some bi-fuel vehicles, which can also fuel with conventional gasoline or diesel, limited availability will not necessarily limit vehicle sales but can limit fuel use. The impact of limited availability on vehicle purchase decisions is largely a function of geographic coverage andmore » consumer perception. In this paper we review previous attempts to quantify the value of availability and present results from two studies that rely upon distinct methodologies. The first study relies upon stated preference data from a discrete choice survey and the second relies upon a station clustering algorithm and a rational actor value of time framework. Results from the two studies provide an estimate of the discrepancy between stated preference cost penalties and a lower bound on potential revealed cost penalties.« less
CFD based aerodynamic modeling to study flight dynamics of a flapping wing micro air vehicle
NASA Astrophysics Data System (ADS)
Rege, Alok Ashok
The demand for small unmanned air vehicles, commonly termed micro air vehicles or MAV's, is rapidly increasing. Driven by applications ranging from civil search-and-rescue missions to military surveillance missions, there is a rising level of interest and investment in better vehicle designs, and miniaturized components are enabling many rapid advances. The need to better understand fundamental aspects of flight for small vehicles has spawned a surge in high quality research in the area of micro air vehicles. These aircraft have a set of constraints which are, in many ways, considerably different from that of traditional aircraft and are often best addressed by a multidisciplinary approach. Fast-response non-linear controls, nano-structures, integrated propulsion and lift mechanisms, highly flexible structures, and low Reynolds aerodynamics are just a few of the important considerations which may be combined in the execution of MAV research. The main objective of this thesis is to derive a consistent nonlinear dynamic model to study the flight dynamics of micro air vehicles with a reasonably accurate representation of aerodynamic forces and moments. The research is divided into two sections. In the first section, derivation of the nonlinear dynamics of flapping wing micro air vehicles is presented. The flapping wing micro air vehicle (MAV) used in this research is modeled as a system of three rigid bodies: a body and two wings. The design is based on an insect called Drosophila Melanogaster, commonly known as fruit-fly. The mass and inertial effects of the wing on the body are neglected for the present work. The nonlinear dynamics is simulated with the aerodynamic data published in the open literature. The flapping frequency is used as the control input. Simulations are run for different cases of wing positions and the chosen parameters are studied for boundedness. Results show a qualitative inconsistency in boundedness for some cases, and demand a better aerodynamic data. The second part of research involves preliminary work required to generate new aerodynamic data for the nonlinear model. First, a computational mesh is created over a 2-D wing section of the MAV model. A finite volume based computational flow solver is used to test different flapping trajectories of the wing section. Finally, a parametric study of the results obtained from the tests is performed.
Huisingh, Carrie; Owsley, Cynthia; Levitan, Emily B; Irvin, Marguerite R; MacLennan, Paul; McGwin, Gerald
2018-05-17
The purpose of this study was to examine the association between secondary task involvement and risk of crash and near-crash involvement among older drivers using naturalistic driving data. Data from drivers aged ≥70 years in the Strategic Highway Research Program (SHRP2) Naturalistic Driving Study database was utilized. The personal vehicle of study participants was equipped with four video cameras enabling recording of the driver and the road environment. Secondary task involvement during a crash or near-crash event was compared to periods of non-crash involvement in a case-crossover study design. Conditional logistic regression was used to generate odds ratios (OR) and 95% confidence intervals (CI). Overall, engaging in any secondary task was not associated with crash (OR=0.94, 95% CI 0.68-1.29) or near-crash (OR=1.08, 95% CI 0.79-1.50) risk. The risk of a major crash event with cell phone use was 3.79 times higher than the risk with no cell phone use (95% CI 1.00-14.37). Other glances into the interior of the vehicle were associated with an increased risk of near-crash involvement (OR=2.55, 95% CI 1.24-5.26). Other distractions external to the vehicle were associated with a decreased risk of crash involvement (OR=0.53, 95% CI 0.30-0.94). Interacting with a passenger and talking/singing were not associated with crash or near-crash risk. Older drivers should avoid any cell phone use and minimize non-driving related eye glances towards the interior of the vehicle while driving. Certain types of events external to the vehicle are associated with a reduced crash risk among older drivers.
Switch Panel wear loading - a parametric study regarding governing train operational factors
NASA Astrophysics Data System (ADS)
Hiensch, E. J. M.; Burgelman, N.
2017-09-01
The acting forces and resulting material degradation at the running surfaces of wheels and rail are determined by vehicle, track, interface and operational characteristics. To effectively manage the experienced wear, plastic deformation and crack development at wheels and rail, the interaction between vehicle and track demands a system approach both in maintenance and in design. This requires insight into the impact of train operational parameters on rail- and wheel degradation, in particular at switches and crossings due to the complex dynamic behaviour of a railway vehicle at a turnout. A parametric study was carried out by means of vehicle-track simulations within the VAMPIRE® multibody simulation software, performing a sensitivity analysis regarding operational factors and their impact on expected switch panel wear loading. Additionally, theoretical concepts were cross-checked with operational practices by means of a case study in response to a dramatic change in lateral rail wear development at specific switches in Dutch track. Data from train operation, track maintenance and track inspection were analysed, providing further insight into the operational dependencies. From the simulations performed in this study, it was found that switch rail lateral wear loading at the diverging route of a 1:9 type turnout is significantly influenced by the level of wheel-rail friction and to a lesser extent by the direction of travel (facing or trailing). The influence of other investigated parameters, being vehicle speed, traction, gauge widening and track layout is found to be small. Findings from the case study further confirm the simulation outcome. This research clearly demonstrates the contribution flange lubrication can have in preventing abnormal lateral wear at locations where the wheel-rail interface is heavily loaded.
Two-layer convective heating prediction procedures and sensitivities for blunt body reentry vehicles
NASA Technical Reports Server (NTRS)
Bouslog, Stanley A.; An, Michael Y.; Wang, K. C.; Tam, Luen T.; Caram, Jose M.
1993-01-01
This paper provides a description of procedures typically used to predict convective heating rates to hypersonic reentry vehicles using the two-layer method. These procedures were used to compute the pitch-plane heating distributions to the Apollo geometry for a wind tunnel test case and for three flight cases. Both simple engineering methods and coupled inviscid/boundary layer solutions were used to predict the heating rates. The sensitivity of the heating results in the choice of metrics, pressure distributions, boundary layer edge conditions, and wall catalycity used in the heating analysis were evaluated. Streamline metrics, pressure distributions, and boundary layer edge properties were defined from perfect gas (wind tunnel case) and chemical equilibrium and nonequilibrium (flight cases) inviscid flow-field solutions. The results of this study indicated that the use of CFD-derived metrics and pressures provided better predictions of heating when compared to wind tunnel test data. The study also showed that modeling entropy layer swallowing and ionization had little effect on the heating predictions.
Accidental Carbon Monoxide Poisoning While Driving: A Case Report With Review of the Literature.
Fisher-Hubbard, Amanda O; Appleford, Colin; Kesha, Kilak; Schmidt, Carl J; Gupta, Avneesh
2018-05-16
Carbon monoxide (CO) is the cause of a significant percentage of fatal poisonings in many countries. It is known that fatalities resulting from CO poisoning are underreported and/or misclassified. Carbon monoxide exposure while driving can occur due to faulty exhaust systems, defective ventilation systems, emission from other vehicles, and even cigarette smoking. We report the case of a 23-year-old woman who was involved in a low-speed motor vehicle collision and was found unresponsive in her vehicle due to CO poisoning. A review of the literature revealed rare vehicle-related accidental CO poisonings.
Estimating Vehicle Fuel Consumption and Emissions Using GPS Big Data.
Kan, Zihan; Tang, Luliang; Kwan, Mei-Po; Zhang, Xia
2018-03-21
The energy consumption and emissions from vehicles adversely affect human health and urban sustainability. Analysis of GPS big data collected from vehicles can provide useful insights about the quantity and distribution of such energy consumption and emissions. Previous studies, which estimated fuel consumption/emissions from traffic based on GPS sampled data, have not sufficiently considered vehicle activities and may have led to erroneous estimations. By adopting the analytical construct of the space-time path in time geography, this study proposes methods that more accurately estimate and visualize vehicle energy consumption/emissions based on analysis of vehicles' mobile activities ( MA ) and stationary activities ( SA ). First, we build space-time paths of individual vehicles, extract moving parameters, and identify MA and SA from each space-time path segment (STPS). Then we present an N-Dimensional framework for estimating and visualizing fuel consumption/emissions. For each STPS, fuel consumption, hot emissions, and cold start emissions are estimated based on activity type, i.e., MA , SA with engine-on and SA with engine-off. In the case study, fuel consumption and emissions of a single vehicle and a road network are estimated and visualized with GPS data. The estimation accuracy of the proposed approach is 88.6%. We also analyze the types of activities that produced fuel consumption on each road segment to explore the patterns and mechanisms of fuel consumption in the study area. The results not only show the effectiveness of the proposed approaches in estimating fuel consumption/emissions but also indicate their advantages for uncovering the relationships between fuel consumption and vehicles' activities in road networks.
A Picture of Burnout: Case Studies and Solutions Toward Improving Radiologists' Well-being.
Restauri, Nicole; Flug, Jonathan A; Mcarthur, Tatum A
This article uses case fictional case vignettes as a vehicle to discuss the complex way organizational and individual factors contribute to physician burnout. The article incorporates a review of the current literature on physician burnout focusing on work place inefficiency and ineffective leadership. Copyright © 2017 Elsevier Inc. All rights reserved.
Cecchel, S; Chindamo, D; Turrini, E; Carnevale, C; Cornacchia, G; Gadola, M; Panvini, A; Volta, M; Ferrario, D; Golimbioschi, R
2018-02-01
This study presents a modelling system to evaluate the impact of weight reduction in light commercial vehicles with diesel engines on air quality and greenhouse gas emissions. The PROPS model assesses the emissions of one vehicle in the aforementioned category and its corresponding reduced-weight version. The results serve as an input to the RIAT+ tool, an air quality integrated assessment modelling system. This paper applies the tools in a case study in the Lombardy region (Italy) and discusses the input data pre-processing, the PROPS-RIAT+ modelling system runs, and the results. Copyright © 2017 Elsevier B.V. All rights reserved.
Influence of switches and crossings on wheel profile evolution in freight vehicles
NASA Astrophysics Data System (ADS)
Casanueva, Carlos; Doulgerakis, Emmanouil; Jönsson, Per-Anders; Stichel, Sebastian
2014-05-01
Wheel reprofiling costs for freight vehicles are a major issue in Sweden, reducing the profitability of freight traffic operations and therefore hindering the modal shift needed for achieving reduced emissions. In order to understand the damage modes in freight vehicles, uniform wear prediction with Archard's wear law has been studied in a two-axle timber transport wagon, and simulation results have been compared to measurements. Challenges of wheel wear prediction in freight wagons are discussed, including the influence of block brakes and switches and crossings. The latter have a major influence on the profile evolution of this case study, so specific simulations are performed and a thorough discussion is carried out.
Mechanical Properties Experimental Study of Engineering Vehicle Refurbished Tire
NASA Astrophysics Data System (ADS)
Qiang, Wang; Xiaojie, Qi; Zhao, Yang; Yunlong, Wang; Guotian, Wang; Degang, Lv
2018-05-01
The vehicle refurbished tire test system was constructed, got load-deformation, load-stiffness, and load-compression ratio property laws of engineering vehicle refurbished tire under the working condition of static state and ground contact, and built radial direction loading deformation mathematics model of 26.5R25 engineering vehicle refurbished tire. The test results show that radial-direction and side-direction deformation value is a little less than that of the new tire. The radial-direction stiffness and compression ratio of engineering vehicle refurbished tire were greatly influenced by radial-direction load and air inflation pressure. When load was certain, radial-direction stiffness would increase with air inflation pressure increasing. When air inflation pressure was certain, compression ratio of engineering vehicle refurbished tire would enlarge with radial-direction load increasing, which was a little less than that of the new and the same type tire. Aging degree of old car-case would exert a great influence on deformation property of engineering vehicle refurbished tire, thus engineering vehicle refurbished tires are suitable to the working condition of low tire pressure and less load.
ERIC Educational Resources Information Center
Bachner, David J.; Malone, Laurence J.; Snider, Mary C.
This volume asserts that international and intercultural experiences are powerful vehicles for first-year college students to learn the perspectives and skills necessary to function interdependently in a rapidly changing and complex world. This thesis is developed through an in-depth case study of efforts to provide such learning opportunities in…
ERIC Educational Resources Information Center
Green, Susan K.; Johnson, C. Douglas
2003-01-01
Educators are becoming increasingly sensitive to accommodating the needs of students from diverse backgrounds in their classes while ensuring that learning occurs. Group work often is the vehicle chosen to stimulate participation and positively affect learning. In this paper, we describe the development of parallel case studies related to…
Rodrigues, Ezequiel; Faria, Paula; Santos, Agostinho; Fraga, Sílvia
2015-07-01
The aim of this study was to analyse the circumstances, the forensic assessment and the legal assessment of police shootings of civilians, according to the severity of the victim's injuries. Sixty-nine cases tried in Portuguese criminal courts were analysed. Of the 32 cases that resulted in death, 16 were on the public thoroughfare and 13 were in the victim's vehicle or in third-party vehicles. The majority of the lethal cases occurred when the region of the body hit was the thorax/abdomen. The firearm most frequently used was a semi-automatic 9 mm pistol. In cases resulting in death police officers involved were convicted whilst those involved in non-lethal cases were acquitted. The results of this study can be taken into account by Portuguese authorities for the implementation of policies that will allow the restriction of firearms use by police officers to situations of imminent danger of death or serious injury and that will make it possible to avoid shooting at fleeing civilians. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Centaur Propellant Thermal Conditioning Study
NASA Technical Reports Server (NTRS)
Blatt, M. H.; Pleasant, R. L.; Erickson, R. C.
1976-01-01
A wicking investigation revealed that passive thermal conditioning was feasible and provided considerable weight advantage over active systems using throttled vent fluid in a Centaur D-1s launch vehicle. Experimental wicking correlations were obtained using empirical revisions to the analytical flow model. Thermal subcoolers were evaluated parametrically as a function of tank pressure and NPSP. Results showed that the RL10 category I engine was the best candidate for boost pump replacement and the option showing the lowest weight penalty employed passively cooled acquisition devices, thermal subcoolers, dry ducts between burns and pumping of subcooler coolant back into the tank. A mixing correlation was identified for sizing the thermodynamic vent system mixer. Worst case mixing requirements were determined by surveying Centaur D-1T, D-1S, IUS, and space tug vehicles. Vent system sizing was based upon worst case requirements. Thermodynamic vent system/mixer weights were determined for each vehicle.
de Koning, Jos J; van der Zweep, Cees-Jan; Cornelissen, Jesper; Kuiper, Bouke
2013-03-01
Optimal pacing strategy was determined for breaking the world speed record on a human-powered vehicle (HPV) using an energy-flow model in which the rider's physical capacities, the vehicle's properties, and the environmental conditions were included. Power data from world-record attempts were compared with data from the model, and race protocols were adjusted to the results from the model. HPV performance can be improved by using an energy-flow model for optimizing race strategy. A biphased in-run followed by a sprint gave best results.
Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon
2014-08-15
Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom P.
This report recalculates the estimated relationship between vehicle mass and societal fatality risk, using alternative groupings by vehicle weight, to test whether the trend of decreasing fatality risk from mass reduction as case vehicle mass increases, holds over smaller increments of the range in case vehicle masses. The NHTSA baseline regression model estimates the relationship using for two weight groups for cars and light trucks; we re-estimated the mass reduction coefficients using four, six, and eight bins of vehicle mass. The estimated effect of mass reduction on societal fatality risk was not consistent over the range in vehicle masses inmore » these weight bins. These results suggest that the relationship indicated by the NHTSA baseline model is a result of other, unmeasured attributes of the mix of vehicles in the lighter vs. heavier weight bins, and not necessarily the result of a correlation between mass reduction and societal fatality risk. An analysis of the average vehicle, driver, and crash characteristics across the various weight groupings did not reveal any strong trends that might explain the lack of a consistent trend of decreasing fatality risk from mass reduction in heavier vehicles.« less
Standing up to the black cloud: case example of narrative therapy in the motor vehicle sector.
Gibson, Michelle
2015-01-01
Using a case study, this article presents narrative therapy as an effective psychotherapy practice for work with victims of motor vehicle accidents. By troubling the standard cognitive behavioral approaches as deficit focused, narrative therapy is outlined as an approach that is focused on the skills and values present in the client's life; it is an approach that allows the client to take authorship over his or her concerns and enact change. This article is meant to be an example of narrative therapy's usefulness and open space for conversation about rehabilitation therapies that focus less on structure and more on strength.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giles, Carrie; Ryder, Carrie; Lommele, Stephen
This case study features the experiences of university partners in the U.S. Department of Energy's (DOE) Workplace Charging Challenge with the installation and management of plug-in electric vehicle (PEV) charging stations.
Bioulac, Stéphanie; Franchi, Jean-Arthur Micoulaud; Arnaud, Mickael; Sagaspe, Patricia; Moore, Nicholas; Salvo, Francesco; Philip, Pierre
2017-10-01
Sleepiness at the wheel is widely believed to be a cause of motor vehicle accidents. Nevertheless, a systematic review of studies investigating this relationship has not yet been published. The objective of this study was to quantify the relationship between sleepiness at the wheel and motor vehicle accidents. A systematic review was performed using Medline, Scopus, and ISI Web of Science. The outcome measure of interest was motor vehicle accident defined as involving four- or two-wheeled vehicles in road traffic, professional and nonprofessional drivers, with or without objective consequences. The exposure was sleepiness at the wheel defined as self-reported sleepiness at the wheel. Studies were included if they provided adjusted risk estimates of motor vehicle accidents related to sleepiness at the wheel. Risk estimates and 95% confidence intervals (95% CIs) were extracted and pooled as odds ratios (ORs) using a random-effect model. Heterogeneity was quantified using Q statistics and the I2 index. The potential causes of heterogeneity were investigated using meta-regressions. Ten cross-sectional studies (51,520 participants), six case-control studies (4904 participants), and one cohort study (13,674 participants) were included. Sleepiness at the wheel was associated with an increased risk of motor vehicle accidents (pooled OR 2.51 [95% CI 1.87; 3.39]). A significant heterogeneity was found between the individual risk estimates (Q = 93.21; I2 = 83%). Sleepiness at the wheel increases the risk of motor vehicle accidents and should be considered when investigating fitness to drive. Further studies are required to explore the nature of this relationship. PROSPERO 2015 CRD42015024805. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.
An Accurate and Generic Testing Approach to Vehicle Stability Parameters Based on GPS and INS
Miao, Zhibin; Zhang, Hongtian; Zhang, Jinzhu
2015-01-01
With the development of the vehicle industry, controlling stability has become more and more important. Techniques of evaluating vehicle stability are in high demand. As a common method, usually GPS sensors and INS sensors are applied to measure vehicle stability parameters by fusing data from the two system sensors. Although prior model parameters should be recognized in a Kalman filter, it is usually used to fuse data from multi-sensors. In this paper, a robust, intelligent and precise method to the measurement of vehicle stability is proposed. First, a fuzzy interpolation method is proposed, along with a four-wheel vehicle dynamic model. Second, a two-stage Kalman filter, which fuses the data from GPS and INS, is established. Next, this approach is applied to a case study vehicle to measure yaw rate and sideslip angle. The results show the advantages of the approach. Finally, a simulation and real experiment is made to verify the advantages of this approach. The experimental results showed the merits of this method for measuring vehicle stability, and the approach can meet the design requirements of a vehicle stability controller. PMID:26690154
Remote sensing of on-road vehicle emissions: Mechanism, applications and a case study from Hong Kong
NASA Astrophysics Data System (ADS)
Huang, Yuhan; Organ, Bruce; Zhou, John L.; Surawski, Nic C.; Hong, Guang; Chan, Edward F. C.; Yam, Yat Shing
2018-06-01
Vehicle emissions are a major contributor to air pollution in cities and have serious health impacts to their inhabitants. On-road remote sensing is an effective and economic tool to monitor and control vehicle emissions. In this review, the mechanism, accuracy, advantages and limitations of remote sensing were introduced. Then the applications and major findings of remote sensing were critically reviewed. It was revealed that the emission distribution of on-road vehicles was highly skewed so that the dirtiest 10% vehicles accounted for over half of the total fleet emissions. Such findings highlighted the importance and effectiveness of using remote sensing for in situ identification of high-emitting vehicles for further inspection and maintenance programs. However, the accuracy and number of vehicles affected by screening programs were greatly dependent on the screening criteria. Remote sensing studies showed that the emissions of gasoline and diesel vehicles were significantly reduced in recent years, with the exception of NOx emissions of diesel vehicles in spite of greatly tightened automotive emission regulations. Thirdly, the experience and issues of using remote sensing for identifying high-emitting vehicles in Hong Kong (where remote sensing is a legislative instrument for enforcement purposes) were reported. That was followed by the first time ever identification and discussion of the issue of frequent false detection of diesel high-emitters using remote sensing. Finally, the challenges and future research directions of on-road remote sensing were elaborated.
Liao, Ruohua; Chen, Xumei; Yu, Lei; Sun, Xiaofei
2018-01-12
Unknown remaining time of signal phase at a signalized intersection generally results in extra accelerations and decelerations that increase variations of operating conditions and thus emissions. A cooperative vehicle-infrastructure system can reduce unnecessary speed changes by establishing communications between vehicles and the signal infrastructure. However, the environmental benefits largely depend on drivers' compliance behaviors. To quantify the effects of drivers' compliance rates on emissions, this study applied VISSIM 5.20 (Planung Transport Verkehr AG, Karlsruhe, Germany) to develop a simulation model for a signalized intersection, in which light duty vehicles were equipped with a cooperative vehicle-infrastructure system. A vehicle-specific power (VSP)-based model was used to estimate emissions. Based on simulation data, the effects of different compliance rates on VSP distributions, emission factors, and total emissions were analyzed. The results show the higher compliance rate decreases the proportion of VSP bin = 0, which means that the frequencies of braking and idling were lower and light duty vehicles ran more smoothly at the intersection if more light duty vehicles complied with the cooperative vehicle-infrastructure system, and emission factors for light duty vehicles decreased significantly as the compliance rate increased. The case study shows higher total emission reductions were observed with higher compliance rate for all of CO₂, NO x , HC, and CO emissions. CO₂ was reduced most significantly, decreased by 16% and 22% with compliance rates of 0.3 and 0.7, respectively.
Liao, Ruohua; Yu, Lei; Sun, Xiaofei
2018-01-01
Unknown remaining time of signal phase at a signalized intersection generally results in extra accelerations and decelerations that increase variations of operating conditions and thus emissions. A cooperative vehicle-infrastructure system can reduce unnecessary speed changes by establishing communications between vehicles and the signal infrastructure. However, the environmental benefits largely depend on drivers’ compliance behaviors. To quantify the effects of drivers’ compliance rates on emissions, this study applied VISSIM 5.20 (Planung Transport Verkehr AG, Karlsruhe, Germany) to develop a simulation model for a signalized intersection, in which light duty vehicles were equipped with a cooperative vehicle-infrastructure system. A vehicle-specific power (VSP)-based model was used to estimate emissions. Based on simulation data, the effects of different compliance rates on VSP distributions, emission factors, and total emissions were analyzed. The results show the higher compliance rate decreases the proportion of VSP bin = 0, which means that the frequencies of braking and idling were lower and light duty vehicles ran more smoothly at the intersection if more light duty vehicles complied with the cooperative vehicle-infrastructure system, and emission factors for light duty vehicles decreased significantly as the compliance rate increased. The case study shows higher total emission reductions were observed with higher compliance rate for all of CO2, NOx, HC, and CO emissions. CO2 was reduced most significantly, decreased by 16% and 22% with compliance rates of 0.3 and 0.7, respectively. PMID:29329214
Are all-terrain vehicle riders willing to pay trail user fees to ride on public lands in the USA?
Stephanie A. Snyder; Robert A. Smail
2009-01-01
Some public lands in the USA offer opportunities for all-terrain vehicle (ATV) riding, but few charge trail use fees. In a case study in the US state of Wisconsin, the contingent valuation method was used to examine riders' willingness to pay (WTP) to ride on public lands. Information on riders' habits, preferences and responses to a dichotomous choice WTP...
Crash fatality and vehicle incompatibility in collisions between cars and light trucks or vans.
Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara
2014-12-01
In crashes between a car and a light truck or van (LTV), car occupants are more likely to be killed than LTV occupants. The extent this is due to the greater harm imposed by LTVs on cars or the greater protection they offer their own occupants is not known. We conducted a case-control study of collisions between two passenger vehicles in the USA during 1990-2008. Cases were all decedents in fatal crashes (N=157,684); one control was selected from each crash in a national probability sample of crashes (N=379,458). Adjusted for the type of vehicle they were riding in and other confounders, occupants of vehicles colliding with any type of LTVs (categorised as compact sport utility vehicles (SUV), full-size SUVs, minivans, full-size vans, compact pickups and full-size pickups) were at higher risk of death compared with occupants colliding with cars. Adjusted for the type of vehicle they crashed with and other confounders, occupants of LTVs in a collision with any vehicle were at lower risk of death compared with car occupants. Compared with a crash between two cars, the overall RR of death in a crash between any of the other 27 different combinations of vehicle types was 1.0 or greater, except for crashes between two full-size pickups, where the RR of death was 0.9. Although LTVs protect their own occupants better than cars do, LTVs are associated with an excess total risk of death in crashes with cars or other LTVs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Keshavarzmohammadian, Azadeh; Henze, Daven K; Milford, Jana B
2017-06-20
This study investigates emission impacts of introducing inexpensive and efficient electric vehicles into the US light duty vehicle (LDV) sector. Scenarios are explored using the ANSWER-MARKAL model with a modified version of the Environmental Protection Agency's (EPA) 9-region database. Modified cost and performance projections for LDV technologies are adapted from the National Research Council (2013) optimistic case. Under our optimistic scenario (OPT) we find 15% and 47% adoption of battery electric vehicles (BEVs) in 2030 and 2050, respectively. In contrast, gasoline vehicles (ICEVs) remain dominant through 2050 in the EPA reference case (BAU). Compared to BAU, OPT gives 16% and 36% reductions in LDV greenhouse gas (GHG) emissions for 2030 and 2050, respectively, corresponding to 5% and 9% reductions in economy-wide emissions. Total nitrogen oxides, volatile organic compounds, and SO 2 emissions are similar in the two scenarios due to intersectoral shifts. Moderate, economy-wide GHG fees have little effect on GHG emissions from the LDV sector but are more effective in the electricity sector. In the OPT scenario, estimated well-to-wheels GHG emissions from full-size BEVs with 100-mile range are 62 gCO 2 -e mi -1 in 2050, while those from full-size ICEVs are 121 gCO 2 -e mi -1 .
Chen, Tai-Hung; Wu, Shu-Pao
2017-08-01
The accurate examination of paint fragments obtained from an accident, such as those obtained from vehicles involved in a hit-and-run case, is often critical in forensic investigations. However, organic pigments are typically minor components of automotive coatings, which makes discrimination difficult. In this study, direct analysis in real time coupled to Q-orbitrap tandem mass spectrometry (DART-MS) was employed to detect a wide range of common organic pigments in vehicle paints. Twelve common organic pigments used in vehicle paints, such as red, yellow, orange, and purple, were tested, and a database was constructed for future examinations of vehicle paint. Two hit-and-run vehicle accident cases, which occurred in New Taipei City, were investigated by Fourier transform infrared (FTIR) spectroscopy and DART-MS. First, FTIR spectroscopy was employed to study the paint samples as a preliminary screening step. Most of the observed IR peaks were attributed to binder and extenders present in paints. The IR peaks corresponding to the organic pigments were found to be weak and overlapped with those corresponding to resins. On the other hand, DART-MS successfully characterized the organic pigments. DART-MS was found to be excellent for rapidly determining the presence of organic pigments in paint samples without the need for a complicated pre-treatment process or lengthy analysis time. Copyright © 2017 Elsevier B.V. All rights reserved.
Traffic-law enforcement and risk of death from motor-vehicle crashes: case-crossover study.
Redelmeier, Donald A; Tibshirani, Robert J; Evans, Leonard
2003-06-28
Driving offences and traffic deaths are common in countries with high rates of motor-vehicle use. We tested whether traffic convictions, because of their direct effect on the recipient, might be associated with a reduced risk of fatal motor-vehicle crashes. We identified licensed drivers in Ontario, Canada, who had been involved in fatal crashes in the past 11 years. We used the case-crossover design to analyse the protective effect of recent convictions on individual drivers. 8975 licensed drivers had fatal crashes during the study period. 21501 driving convictions were recorded for all drivers from the date of obtaining a full licence to the date of fatal crash, equivalent to about one conviction per driver every 5 years. The risk of a fatal crash in the month after a conviction was about 35% lower than in a comparable month with no conviction for the same driver (95% CI 20-45, p=0.0002). The benefit lessened substantially by 2 months and was not significant by 3-4 months. The benefit was not altered by age, previous convictions, and other personal characteristics; was greater for speeding violations with penalty points than speeding violations without points; was no different for crashes of differing severity; and was not seen in drivers whose licences were suspended. Traffic-law enforcement effectively reduces the frequency of fatal motor-vehicle crashes in countries with high rates of motor-vehicle use. Inconsistent enforcement, therefore, may contribute to thousands of deaths each year worldwide.
Singh, Rajeev Kumar; Yabar, Helmut; Nozaki, Noriko; Niraula, Baburam; Mizunoya, Takeshi
2017-08-01
A growing population and urbanization is a challenge for finite natural resources. Without strict regulation to recycle, recover and reuse resources, waste is discarded with no value. Every year throughout the world, more than twenty-five million vehicles turn into end-of-life vehicles (ELV) and most of their valuable resources end up in landfill sites. This research analyses the effect of regulation on ELV innovation for additional recovery of resources in Japan and EU nations using patent data as a proxy. The analysis determines the statistical difference in patent activity before and after regulations were enacted in the case studies. The relevant data on ELV technologies was gathered for the period 1985-2013. The study suggests that in general environmental regulation in Japan drove innovation and reveals that environmental policy in Japan was more effective in enabling innovation compared to EU nations. Specifically, the results from these developed countries can be used by the rapidly growing developing countries in automobile manufacturing like China for amendment of their ELV regulation accordingly. Copyright © 2017 Elsevier Ltd. All rights reserved.
Launch of a Vehicle from a Ramp
ERIC Educational Resources Information Center
Cross, Rod
2011-01-01
A vehicle proceeding up an inclined ramp will become airborne if the ramp comes to a sudden end and if the vehicle fails to stop before it reaches the end of the ramp. A vehicle may also become airborne if it passes over the top of a hill at sufficient speed. In both cases, the vehicle becomes airborne if the point of support underneath the…
2013-12-05
CAPE CANAVERAL, Fla. -- The first of four new emergency egress vehicles, called Mine-Resistant Ambush-Protection, or MRAP, vehicles arrived at Kennedy Space Center in Florida from the U.S. Army Red River Depot in Texarkana, Texas. Each vehicle will be processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Jim Grossmann
2013-12-05
CAPE CANAVERAL, Fla. -- The first of four new emergency egress vehicles, called Mine-Resistant Ambush-Protection, or MRAP, vehicles arrived at Kennedy Space Center in Florida from the U.S. Army Red River Depot in Texarkana, Texas. Each vehicle will be processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Jim Grossmann
2013-12-05
CAPE CANAVERAL, Fla. -- The first of four new emergency egress vehicles, called Mine-Resistant Ambush-Protection, or MRAP, vehicles arrived at Kennedy Space Center in Florida from the U.S. Army Red River Depot in Texarkana, Texas. Each vehicle will be processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Jim Grossmann
NASA Technical Reports Server (NTRS)
Zwack, M. R.; Dees, P. D.; Thomas, H. D.; Polsgrove, T. P.; Holt, J. B.
2017-01-01
The primary purpose of the multiPOST tool is to enable the execution of much larger sets of vehicle cases to allow for broader trade space exploration. However, this exploration is not achieved solely with the increased case throughput. The multiPOST tool is applied to carry out a Design of Experiments (DOE), which is a set of cases that have been structured to capture a maximum amount of information about the design space with minimal computational effort. The results of the DOE are then used to fit a surrogate model, ultimately enabling parametric design space exploration. The approach used for the MAV study includes both DOE and surrogate modeling. First, the primary design considerations for the vehicle were used to develop the variables and ranges for the multiPOST DOE. The final set of DOE variables were carefully selected in order to capture the desired vehicle trades and take into account any special considerations for surrogate modeling. Next, the DOE sets were executed through multiPOST. Following successful completion of the DOE cases, a manual verification trial was performed. The trial involved randomly selecting cases from the DOE set and running them by hand. The results from the human analyst's run and multiPOST were then compared to ensure that the automated runs were being executed properly. Completion of the verification trials was then followed by surrogate model fitting. After fits to the multiPOST data were successfully created, the surrogate models were used as a stand-in for POST2 to carry out the desired MAV trades. Using the surrogate models in lieu of POST2 allowed for visualization of vehicle sensitivities to the input variables as well as rapid evaluation of vehicle performance. Although the models introduce some error into the output of the trade study, they were very effective at identifying areas of interest within the trade space for further refinement by human analysts. The next section will cover all of the ground rules and assumptions associated with DOE setup and multiPOST execution. Section 3.1 gives the final DOE variables and ranges, while section 3.2 addresses the POST2 specific assumptions. The results of the verification trials are given in section 4. Section 5 gives the surrogate model fitting results, including the goodness-of-fit metrics for each fit. Finally, the MAV specific results are discussed in section 6.
Mine-Resistant Ambush-Protection vehicles
2014-02-13
CAPE CANAVERAL, Fla. – One of four new emergency egress vehicles, called Mine-Resistant Ambush-Protection, or MRAP, vehicles is driven to the Maintenance and Operations Facility at Kennedy Space Center in Florida. The MRAPs arrived from the U.S. Army Red River Depot in Texarkana, Texas in December 2013. The vehicles were processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Kim Shiflett
Mine-Resistant Ambush-Protection vehicles
2014-02-13
CAPE CANAVERAL, Fla. – A URS Federal Services worker pulls down the steps to the entrance of one of the four new emergency egress vehicles, called Mine-Resistant Ambush-Protected, or MRAP, vehicles at the Maintenance and Operations Facility at NASA’s Kennedy Space Center in Florida. The MRAPs arrived from the U.S. Army Red River Depot in Texarkana, Texas in December 2013. The vehicles were processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Kim Shiflett
Mine-Resistant Ambush-Protection vehicles
2014-02-13
CAPE CANAVERAL, Fla. – A view of the interior of one of four new emergency egress vehicles, called Mine-Resistant Ambush-Protected, or MRAP, vehicles is shown. The MRAPs are at the Maintenance and Operations Facility at NASA’s Kennedy Space Center in Florida. The MRAPs arrived from the U.S. Army Red River Depot in Texarkana, Texas in December 2013. The vehicles were processed in and then transported to the Rotation, Processing and Surge Facility near the Vehicle Assembly Building for temporary storage. The Ground Systems Development and Operations Program at Kennedy led the efforts to an emergency egress vehicle that future astronauts could quickly use to leave the Launch Complex 39 area in case of an emergency. During crewed launches of NASA’s Space Launch System and Orion spacecraft, the MRAP will be stationed by the slidewire termination area at the pad. In case of an emergency, the crew will ride a slidewire to the ground and immediately board the MRAP for safe egress from the pad. The new vehicles replace the M-113 vehicles that were used during the Space Shuttle Program. Photo credit: NASA/Kim Shiflett
Bunn, Terry L; Slavova, Svetla; Rock, Peter J
2017-11-22
There is ongoing concern at the national level about the availability of adequate commercial vehicle rest areas and truck stops for commercial vehicle drivers to rest or to wait for a delivery window. A retrospective case-control study was conducted to determine the association between the occurrence of sleepiness/fatigue-related (cases) vs. all other human factor-related commercial vehicle driver at-fault crashes (controls) and proximity to rest areas, weigh stations with rest havens, and truck stops. Commercial vehicle driver at-fault crashes involving sleepiness/fatigue were more likely to occur on roadways where the nearest rest areas/weigh stations with rest havens/truck stops were located 20 miles or more from the commercial vehicle crash site (Odds Ratio [OR]=2.32; Confidence Interval [CI] 1.615, 3.335] for 20-39.9 miles vs. <20 miles; and OR=6.788 [CI 2.112, 21.812] for 40+ miles) compared to commercial vehicle at-fault driver crashes with human factors other than sleepiness/fatigue cited in crash reports. Commercial vehicle driver at-fault crashes involving sleepiness/fatigue also were more likely to occur on parkways compared to interstates (adjusted OR=3.747 [CI 2.83, 4.95]), during nighttime hours (adjusted OR=6.199 [CI 4.733, 8.119]), and on dry pavement (adjusted OR 1.909, [CI 1.373, 2.655]). The use of statewide crash data analysis coupled with ArcGIS mapping capabilities provided the opportunity to both statistically determine and to visualize the association between rest area/weigh station with rest haven/truck stop distance and the occurrence of commercial vehicle driver at-fault crashes involving sleepiness/fatigue. Implementation and evaluation of commercial vehicle employer policies and interventions such as the use of commercial vehicle driver fatigue alert systems may help to reduce fatigue and sleepiness in commercial vehicle drivers. These results can be used by state and local highway transportation officials to inform and increase truck parking availability, especially on parkways. Copyright © 2017 Elsevier Ltd. All rights reserved.
Vehicle model year and crash outcomes: a CIREN study.
Ryb, Gabriel E; Dischinger, Patricia C; Ho, Shiu
2009-12-01
To quantify the effect of model year (MY) on the occurrence of severe injuries and death after involvement in motor vehicle crashes. Cases involving adult front seat occupants of vehicles MY > or = 1994 equipped with frontal airbags were selected from the Crash Injury Research and Engineering Network (CIREN) database. Cases were grouped by MY: 1994-1997, 1998-2004, and 2005-2007 (MY groups [MYG] 1, 2, and 3, respectively. MYGs were compared in relation to mortality, Injury Severity Score (ISS), and the occurrence of Abbreviated Injury Severity score (AIS) 3+ and AIS4+ injuries to each body region using Mantel Haenszel chi-square, Kruskal-Wallis, and Bonferroni corrected t test. To adjust for confounders, multiple logistic regression models were built to explore the association of MYG with death. Covariates included age, BMI, delta v, principal direction of force (PDOF), restraint use, and vehicle type. A total of 1888 cases was distributed within MYG1 (34%), MYG2 (62%), and MYG (34%). Age, gender, BMI, and PDOF distribution did not differ among MYGs. Though ISS distribution was not different, a decrease in the occurrence of AIS4+ of the thorax and spine regions was noted over time. Mortality also decreased over time (18, 9, and 4% MYG 1, 2, and 3, respectively). Multivariate analysis revealed a protective effect of MYG2 and MGY3 (odds ratio [OR], 0.57 [0.44-0.75] and 0.22 [0.07-0.50], respectively) in relation to death. Front seat occupants of later MY vehicles injured during crashes experience a decreased likelihood of very severe thoracic injuries, spinal injuries, and death.
USDA-ARS?s Scientific Manuscript database
During 2013 Italy experienced an increase in cases of hepatitis A virus (HAV) infection and the epidemic HAV strain has been characterized as genotype IA. Preliminary epidemiological, microbiological and environmental investigations suggested mixed frozen berries as the possible vehicle of infection...
Kullgren, A; Lie, A; Tingvall, C
1994-02-01
Vehicle deformations are important sources for information about the performance of safety systems. Photogrammetry has developed vastly under recent years. In this study modern photogrammetrical methods have been used for vehicle deformation analysis. The study describes the equipment for documentation and recording in the field (semi-metric camera), and a system for photogrammetrical measurements of the images in laboratory environment (personal computer and digitizing tablet). The material used is approximately 500 collected and measured cases. The study shows that the reliability is high and that accuracies around 15mm can be achieved even if the equipment and routines used are relatively simple. The effects of further development using video cameras for data capture and digital images for measurements are discussed.
Crash-Related Mortality and Model Year: Are Newer Vehicles Safer?
Ryb, Gabriel E; Dischinger, Patricia C; McGwin, Gerald; Griffin, Russell L
2011-01-01
Objective: The objective of this study was to determine whether occupants of newer vehicles experience a lower risk of crash-related mortality. Methods: The occurrence of death was studied in relation to vehicle model year (MY) among front seat vehicular occupants, age ≥ 16 captured in the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) between 2000 and 2008. The associations between death and other occupant, vehicular and crash characteristics were also explored. Multiple logistic regression models for the prediction of death were built with model year as the independent variable and other characteristics linked to death as covariates. Imputation was used for missing data; weighted data was used. Results: A total of 70,314 cases representing 30,514,372 weighted cases were available for analysis. Death occurred in 0.6% of the weighted population. Death was linked to age>60, male gender, higher BMI, near lateral direction of impact, high delta v, rollover, ejection and vehicle mismatch, and negatively associated with seatbelt use and rear and far lateral direction of impact. Mortality decreased with later model year groups (MY<94 0.78%, MY 94–97 0.53%, MY 98-04 0.51% and MY 05–08 0.38%, p=<0.0001). After adjustment for confounders, MY 94–97, MY 98-04 and MY 05–08 showed decreased odds of death [OR 0.80 (0.69–0.94), 0.82 (0.70–0.97), and 0.67 (0.47–0.96), respectively] when compared to MY <94. Conclusion: Newer vehicles are associated with lower crash-related mortality. Their introduction into the vehicle fleet may explain, at least in part, the decrease in mortality rates in the past two decades. PMID:22105389
Matsui, Yasuhiro; Oikawa, Shoko; Ando, Kenichi
2013-11-01
The first purpose of this study is to clarify the relation between the car impact velocity and pedestrian injury severity or mortality risk. We investigated the frequency of serious injuries and fatalities of pedestrians using vehicle-pedestrian accident data from the database of the Institute for Traffic Accident Research and Data Analysis (ITARDA) in Japan. The vehicle types considered are sedans, minivans, and box vans (ordinary automobiles) and light passenger cars and light cargo vans (light automobiles). The results revealed that a 10-km/h reduction in impact velocity could mitigate severe pedestrian injuries in cases involving impact velocities of 40 km/h or more for the five vehicle types analyzed. Specifically, if the impact velocity was 30 km/h or less, the frequency of serious injuries was less than 27% and the frequency of fatalities was less than 5% for the five vehicle types. Therefore, if the collision damage mitigation braking system (CDMBS) that uses a sensor to detect pedestrians can effectively reduce the impact velocity for various vehicle types, pedestrian injuries will be greatly mitigated. The second purpose of this study is to identify the factors that affect injury risk. Impact experiments were conducted in which a sedan impacted against a pedestrian full-scale dummy at 40 km/h and a pedestrian headform impactor was impacted against a road surface. The results indicated that the risk of pedestrian serious injury was significantly affected by multiple impact conditions, such as the pedestrian height, car impact velocity, car frontal shape, and car stiffness in cases where the car impacted the pedestrian's head, the degrees of influence of which were driven by the vehicle impact velocity.
Crash-related mortality and model year: are newer vehicles safer?
Ryb, Gabriel E; Dischinger, Patricia C; McGwin, Gerald; Griffin, Russell L
2011-01-01
The objective of this study was to determine whether occupants of newer vehicles experience a lower risk of crash-related mortality. The occurrence of death was studied in relation to vehicle model year (MY) among front seat vehicular occupants, age ≥ 16 captured in the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) between 2000 and 2008. The associations between death and other occupant, vehicular and crash characteristics were also explored. Multiple logistic regression models for the prediction of death were built with model year as the independent variable and other characteristics linked to death as covariates. Imputation was used for missing data; weighted data was used. A total of 70,314 cases representing 30,514,372 weighted cases were available for analysis. Death occurred in 0.6% of the weighted population. Death was linked to age>60, male gender, higher BMI, near lateral direction of impact, high delta v, rollover, ejection and vehicle mismatch, and negatively associated with seatbelt use and rear and far lateral direction of impact. Mortality decreased with later model year groups (MY<94 0.78%, MY 94-97 0.53%, MY 98-04 0.51% and MY 05-08 0.38%, p=<0.0001). After adjustment for confounders, MY 94-97, MY 98-04 and MY 05-08 showed decreased odds of death [OR 0.80 (0.69-0.94), 0.82 (0.70-0.97), and 0.67 (0.47-0.96), respectively] when compared to MY <94. Newer vehicles are associated with lower crash-related mortality. Their introduction into the vehicle fleet may explain, at least in part, the decrease in mortality rates in the past two decades.
Optimization of a simplified automobile finite element model using time varying injury metrics.
Gaewsky, James P; Danelson, Kerry A; Weaver, Caitlin M; Stitzel, Joel D
2014-01-01
In 2011, frontal crashes resulted in 55% of passenger car injuries with 10,277 fatalities and 866,000 injuries in the United States. To better understand frontal crash injury mechanisms, human body finite element models (FEMs) can be used to reconstruct Crash Injury Research and Engineering Network (CIREN) cases. A limitation of this method is the paucity of vehicle FEMs; therefore, we developed a functionally equivalent simplified vehicle model. The New Car Assessment Program (NCAP) data for our selected vehicle was from a frontal collision with Hybrid III (H3) Anthropomorphic Test Device (ATD) occupant. From NCAP test reports, the vehicle geometry was created and the H3 ATD was positioned. The material and component properties optimized using a variation study process were: steering column shear bolt fracture force and stroke resistance, seatbelt pretensioner force, frontal and knee bolster airbag stiffness, and belt friction through the D-ring. These parameters were varied using three successive Latin Hypercube Designs of Experiments with 130-200 simulations each. The H3 injury response was compared to the reported NCAP frontal test results for the head, chest and pelvis accelerations, and seat belt and femur forces. The phase, magnitude, and comprehensive error factors, from a Sprague and Geers analysis were calculated for each injury metric and then combined to determine the simulations with the best match to the crash test. The Sprague and Geers analyses typically yield error factors ranging from 0 to 1 with lower scores being more optimized. The total body injury response error factor for the most optimized simulation from each round of the variation study decreased from 0.466 to 0.395 to 0.360. This procedure to optimize vehicle FEMs is a valuable tool to conduct future CIREN case reconstructions in a variety of vehicles.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kevin Morrow; Dimitri Hochard; Jeff Wishart
2011-09-01
Plug-in electric vehicles (PEVs), including battery electric, plug-in hybrid electric, and extended range electric vehicles, are under evaluation by the U.S. Department of Energy's Advanced Vehicle Testing Activity (AVTA) and other various stakeholders to better understand their capability and potential petroleum reduction benefits. PEVs could allow users to significantly improve fuel economy over a standard hybrid electric vehicles, and in some cases, depending on daily driving requirements and vehicle design, PEVs may have the ability to eliminate petroleum consumption entirely for daily vehicle trips. The AVTA is working jointly with the Society of Automotive Engineers (SAE) to assist in themore » further development of standards necessary for the advancement of PEVs. This report analyzes different methods and available hardware for advanced communications between the electric vehicle supply equipment (EVSE) and the PEV; particularly Power Line Devices and their physical layer. Results of this study are not conclusive, but add to the collective knowledge base in this area to help define further testing that will be necessary for the development of the final recommended SAE communications standard. The Idaho National Laboratory and the Electric Transportation Applications conduct the AVTA for the United States Department of Energy's Vehicle Technologies Program.« less
Lateral impact injuries with side airbag deployments—A descriptive study
Yoganandan, Narayan; Pintar, Frank A.; Zhang, Jiangyue; Gennarelli, Thomas A.
2006-01-01
The present study was designed to provide descriptive data on side impact injuries in vehicles equipped with side airbags using the United States National Automotive Sampling System (NASS). The database was queried with the constraint that all vehicles must adhere to the Federal Motor Vehicle Safety Standards FMVSS 214, injured occupants be in the front outboard seats with no rollovers or ejections, and side impacts airbags be deployed in lateral crashes. Out of the 7812 crashes in the 1997–2004 weighted NASS files, AIS ≥ 2 level injuries occurred to 5071 occupants. There were 3828 cases of torso-only airbags, 955 cases of torso–head bag combination, and 288 inflatable tubular structure/curtain systems. Side airbags were not attributed to be the cause of head or chest injury to any occupant at this level of severity. The predominance of torso-only airbags followed by torso–head airbag combination reflected vehicle model years and changing technology. Head and chest injuries were coupled for the vast majority of occupants with injuries to more than one body region. Comparing literature data for side impacts without side airbag deployments, the presence of a side airbag decreased AIS = 2 head, chest, and extremity injuries when examining raw data incidence rates. Although this is the first study to adopt strict inclusion–exclusion criteria for side crashes with side airbag deployments, future studies are needed to assess side airbag efficacy using datasets such as matched-pair occupants in side impacts. PMID:16911812
Smooth handling: The lack of safety‐related consumer information in car advertisements
Wilson, Nick; Maher, Anthony; Thomson, George; Keall, Michael
2007-01-01
Objective To examine the content and trends of safety‐related consumer information in magazine vehicle advertisements, as a case study within the worldwide marketing of vehicles. Methods Content analysis of popular current affairs magazines in New Zealand for the 5‐year period 2001–2005 was undertaken (n = 514 advertisements), supplemented with vehicle data from official websites. Results Safety information in advertisements for light passenger vehicles was relatively uncommon with only 27% mentioning one or more of nine key safety features examined (average: 1.7 out of nine features in this 27%). Also included were potentially hazardous features of: speed imagery (in 29% of advertisements), power references (14%), and acceleration data (4%). The speed and power aspects became relatively more common over the 5‐year period (p < 0.05 for trend). Conclusions To enhance informed consumer choice and improve injury prevention, governments should consider regulating the content of vehicle advertisements and vehicle marketing – as already occurs with many other consumer products. PMID:17916885
Smooth handling: the lack of safety-related consumer information in car advertisements.
Wilson, Nick; Maher, Anthony; Thomson, George; Keall, Michael
2007-10-01
To examine the content and trends of safety-related consumer information in magazine vehicle advertisements, as a case study within the worldwide marketing of vehicles. Content analysis of popular current affairs magazines in New Zealand for the 5-year period 2001-2005 was undertaken (n = 514 advertisements), supplemented with vehicle data from official websites. Safety information in advertisements for light passenger vehicles was relatively uncommon with only 27% mentioning one or more of nine key safety features examined (average: 1.7 out of nine features in this 27%). Also included were potentially hazardous features of: speed imagery (in 29% of advertisements), power references (14%), and acceleration data (4%). The speed and power aspects became relatively more common over the 5-year period (p < 0.05 for trend). To enhance informed consumer choice and improve injury prevention, governments should consider regulating the content of vehicle advertisements and vehicle marketing - as already occurs with many other consumer products.
Vehicle systems: coupled and interactive dynamics analysis
NASA Astrophysics Data System (ADS)
Vantsevich, Vladimir V.
2014-11-01
This article formulates a new direction in vehicle dynamics, described as coupled and interactive vehicle system dynamics. Formalised procedures and analysis of case studies are presented. An analytical consideration, which explains the physics of coupled system dynamics and its consequences for dynamics of a vehicle, is given for several sets of systems including: (i) driveline and suspension of a 6×6 truck, (ii) a brake mechanism and a limited slip differential of a drive axle and (iii) a 4×4 vehicle steering system and driveline system. The article introduces a formal procedure to turn coupled system dynamics into interactive dynamics of systems. A new research direction in interactive dynamics of an active steering and a hybrid-electric power transmitting unit is presented and analysed to control power distribution between the drive axles of a 4×4 vehicle. A control strategy integrates energy efficiency and lateral dynamics by decoupling dynamics of the two systems thus forming their interactive dynamics.
Minimum weight passive insulation requirements for hypersonic cruise vehicles.
NASA Technical Reports Server (NTRS)
Ardema, M. D.
1972-01-01
Analytical solutions are derived for two representative cases of the transient heat conduction equation to determine the minimum weight requirements for passive insulation systems of hypersonic cruise vehicles. The cases discussed are the wet wall case with the interior wall temperature held to that of the boiling point of the fuel throughout the flight, and the dry wall case where the heat transferred through the insulation is absorbed by the interior structure whose temperature is allowed to rise.
NASA Technical Reports Server (NTRS)
Cragg, Clinton H.; Bowman, Howard; Wilson, John E.
2011-01-01
The NASA Engineering and Safety Center (NESC) was requested to provide computational modeling to support the establishment of a safe separation distance surrounding the Kennedy Space Center (KSC) Vehicle Assembly Building (VAB). The two major objectives of the study were 1) establish a methodology based on thermal flux to determine safe separation distances from the Kennedy Space Center's (KSC's) Vehicle Assembly Building (VAB) with large numbers of solid propellant boosters containing hazard division 1.3 classification propellants, in case of inadvertent ignition; and 2) apply this methodology to the consideration of housing eight 5-segment solid propellant boosters in the VAB. The results of the study are contained in this report.
Resource Tracking Model Updates and Trade Studies
NASA Technical Reports Server (NTRS)
Chambliss, Joe; Stambaugh, Imelda; Moore, Michael
2016-01-01
The Resource Tracking Model has been updated to capture system manager and project manager inputs. Both the Trick/General Use Nodal Network Solver Resource Tracking Model (RTM) simulator and the RTM mass balance spreadsheet have been revised to address inputs from system managers and to refine the way mass balance is illustrated. The revisions to the RTM included the addition of a Plasma Pyrolysis Assembly (PPA) to recover hydrogen from Sabatier Reactor methane, which was vented in the prior version of the RTM. The effect of the PPA on the overall balance of resources in an exploration vehicle is illustrated in the increased recycle of vehicle oxygen. Case studies have been run to show the relative effect of performance changes on vehicle resources.
NASA Astrophysics Data System (ADS)
Kamal, M. A.; Youlla, D.
2018-03-01
Municipal solid waste (MSW) transportation in Pontianak City becomes an issue that need to be tackled by the relevant agencies. The MSW transportation service in Pontianak City currently requires very high resources especially in vehicle usage. Increasing the number of fleets has not been able to increase service levels while garbage volume is growing every year along with population growth. In this research, vehicle routing optimization approach was used to find optimal and efficient routes of vehicle cost in transporting garbage from several Temporary Garbage Dump (TGD) to Final Garbage Dump (FGD). One of the problems of MSW transportation is that there is a TGD which exceed the the vehicle capacity and must be visited more than once. The optimal computation results suggest that the municipal authorities only use 3 vehicles from 5 vehicles provided with the total minimum cost of IDR. 778,870. The computation time to search optimal route and minimal cost is very time consuming. This problem is influenced by the number of constraints and decision variables that have are integer value.
Chai, C; Wong, Y D
2014-02-01
At intersection, vehicles coming from different directions conflict with each other. Improper geometric design and signal settings at signalized intersection will increase occurrence of conflicts between road users and results in a reduction of the safety level. This study established a cellular automata (CA) model to simulate vehicular interactions involving right-turn vehicles (as similar to left-turn vehicles in US). Through various simulation scenarios for four case cross-intersections, the relationships between conflict occurrences involving right-turn vehicles with traffic volume and right-turn movement control strategies are analyzed. Impacts of traffic volume, permissive right-turn compared to red-amber-green (RAG) arrow, shared straight-through and right-turn lane as well as signal setting are estimated from simulation results. The simulation model is found to be able to provide reasonable assessment of conflicts through comparison of existed simulation approach and observed accidents. Through the proposed approach, prediction models for occurrences and severity of vehicle conflicts can be developed for various geometric layouts and traffic control strategies. Copyright © 2013 Elsevier Ltd. All rights reserved.
Fuel economy and life-cycle cost analysis of a fuel cell hybrid vehicle
NASA Astrophysics Data System (ADS)
Jeong, Kwi Seong; Oh, Byeong Soo
The most promising vehicle engine that can overcome the problem of present internal combustion is the hydrogen fuel cell. Fuel cells are devices that change chemical energy directly into electrical energy without combustion. Pure fuel cell vehicles and fuel cell hybrid vehicles (i.e. a combination of fuel cell and battery) as energy sources are studied. Considerations of efficiency, fuel economy, and the characteristics of power output in hybridization of fuel cell vehicle are necessary. In the case of Federal Urban Driving Schedule (FUDS) cycle simulation, hybridization is more efficient than a pure fuel cell vehicle. The reason is that it is possible to capture regenerative braking energy and to operate the fuel cell system within a more efficient range by using battery. Life-cycle cost is largely affected by the fuel cell size, fuel cell cost, and hydrogen cost. When the cost of fuel cell is high, hybridization is profitable, but when the cost of fuel cell is less than 400 US$/kW, a pure fuel cell vehicle is more profitable.
Encouraging vehicle-to-grid (V2G) participation through premium tariff rates
NASA Astrophysics Data System (ADS)
Richardson, David B.
2013-12-01
The provision of vehicle-to-grid (V2G) services to an electric grid by electric vehicles (EVs) can potentially reduce the cost of vehicle ownership through revenue generation. Recent studies indicate that yearly vehicle profit from V2G may not be sufficient to induce widespread participation. This paper investigates the feasibility of a premium tariff rate for V2G power, similar to current feed-in-tariff (FIT) programs for renewable energy. Using Ontario, Canada as a case study, an hourly time-series model for a fleet of commuter EVs is created. Tariff rates for V2G peak power are calculated based on the same return on investment as the current FIT for renewable energy in Ontario. The tariff rates are competitive with the renewable energy tariffs, especially when EVs are allowed to provide ancillary services to the grid in addition to peak power. Despite the guaranteed rate of return, yearly vehicle profit is low. Two variations are considered to increase vehicle profit, thereby enhancing the attractiveness of V2G. A higher return on investment is favored over direct benefits offered to EV owners. A higher return on investment may be justifiable based on the higher level of risk inherent in V2G when compared to renewable energy.
Tonkin, Matthew; Woodhams, Jessica; Bond, John W; Loe, Trudy
2010-01-01
Geographical profiling is an investigative methodology sometimes employed by the police to predict the residence of an unknown offender from the locations of his/her crimes. The validity of geographical profiling, however, has not been fully explored for certain crime types. This study, therefore, presents a preliminary test of the potential for geographical profiling with a sample of 145 serial vehicle thieves from the U.K. The behavioural assumptions underlying geographical profiling (distance decay and domocentricity) are tested and a simple practical test of profiling using the spatial mean is presented. There is evidence for distance decay but not domocentricity among the spatial behaviour of car thieves from the U.K. A degree of success was achieved when applying the spatial mean on a case-by-case basis. The level of success varied, however, and neither series length in days nor number of crimes could account for the variation. The findings question previously held assumptions regarding geographical profiling and have potential theoretical and practical implications for the study and investigation of vehicle theft in the U.K. 2009 John Wiley & Sons, Ltd.
Code of Federal Regulations, 2010 CFR
2010-04-01
... maximum gross vehicle weight shall be 80,000 pounds except where lower gross vehicle weight is dictated by... of axles, or a vehicle is 20,000 pounds. (d) The maximum gross weight on tandem axles is 34,000... first and last axle is 36 feet or more. In no case shall the total gross weight of a vehicle exceed 80...
NASA Technical Reports Server (NTRS)
Venkatesan, C.; Friedmann, P. P.
1987-01-01
This report is a sequel to the earlier report titled, Aeroelastic Effects in Multi-Rotor Vehicles with Application to Hybrid Heavy Lift System, Part 1: Formulation of Equations of Motion (NASA CR-3822). The trim and stability equations are presented for a twin rotor system with a buoyant envelope and an underslung load attached to a flexible supporting structure. These equations are specialized for the case of hovering flight. A stability analysis, for such a vehicle with 31 degrees of freedom, yields a total of 62 eigenvalues. A careful parametric study is performed to identify the various blade and vehicle modes, as well as the coupling between various modes. Finally, it is shown that the coupled rotor/vehicle stability analysis provides information on both the aeroelastic stability as well as complete vehicle dynamic stability. Also presented are the results of an analytical study aimed at predicting the aeromechanical stability of a single rotor helicopter in ground resonance. The theoretical results are found to be in good agreement with the experimental results, thereby validating the analytical model for the dynamics of the coupled rotor/support system.
MMSE Estimator for Children’s Speech with Car and Weather Noise
NASA Astrophysics Data System (ADS)
Sayuthi, V.
2018-04-01
Previous research mentioned that most people need and use vehicles for various purposes, in this recent time and future, as a means of traveling. Many ways can be done in a vehicle, such as for enjoying entertainment, and doing work, so vehicles not just only as a means of traveling. In this study, we will examine the children’s speech from a girl in the vehicle that affected by noise disturbances from the sound source of car noise and the weather sound noise around it, in this case, the rainy weather noise. Vehicle sounds may be from car engine or car air conditioner. The minimum mean square error (MMSE) estimator is used as an attempt to obtain or detect the children’s clear speech by representing simulation research as random process signal that factored by the autocorrelation of both the child’s voice and the disturbance noise signal. This MMSE estimator can be considered as wiener filter as the clear sound are reconstructed again. We expected that the results of this study can help as the basis for development of entertainment or communication technology for passengers of vehicles in the future, particularly using MMSE estimators.
Frey, H Christopher; Zhai, Haibo; Rouphail, Nagui M
2009-11-01
This study presents a methodology for estimating high-resolution, regional on-road vehicle emissions and the associated reductions in air pollutant emissions from vehicles that utilize alternative fuels or propulsion technologies. The fuels considered are gasoline, diesel, ethanol, biodiesel, compressed natural gas, hydrogen, and electricity. The technologies considered are internal combustion or compression engines, hybrids, fuel cell, and electric. Road link-based emission models are developed using modal fuel use and emission rates applied to facility- and speed-specific driving cycles. For an urban case study, passenger cars were found to be the largest sources of HC, CO, and CO(2) emissions, whereas trucks contributed the largest share of NO(x) emissions. When alternative fuel and propulsion technologies were introduced in the fleet at a modest market penetration level of 27%, their emission reductions were found to be 3-14%. Emissions for all pollutants generally decreased with an increase in the market share of alternative vehicle technologies. Turnover of the light duty fleet to newer Tier 2 vehicles reduced emissions of HC, CO, and NO(x) substantially. However, modest improvements in fuel economy may be offset by VMT growth and reductions in overall average speed.
Real-time simulation model of the HL-20 lifting body
NASA Technical Reports Server (NTRS)
Jackson, E. Bruce; Cruz, Christopher I.; Ragsdale, W. A.
1992-01-01
A proposed manned spacecraft design, designated the HL-20, has been under investigation at Langley Research Center. Included in that investigation are flight control design and flying qualities studies utilizing a man-in-the-loop real-time simulator. This report documents the current real-time simulation model of the HL-20 lifting body vehicle, known as version 2.0, presently in use at NASA Langley Research Center. Included are data on vehicle aerodynamics, inertias, geometries, guidance and control laws, and cockpit displays and controllers. In addition, trim case and dynamic check case data is provided. The intent of this document is to provide the reader with sufficient information to develop and validate an equivalent simulation of the HL-20 for use in real-time or analytical studies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stephens, T. S.; Birky, A.; Gohlke, David
Under a diverse set of programs, the Vehicle Technologies and Fuel Cell Technologies Offices of the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy invest in early-stage research of advanced batteries and electrification, engines and fuels, materials, and energy-efficient mobility systems; hydrogen production, delivery, and storage; and fuel cell technologies. This report documents the estimated benefits of successful development and implementation of advanced vehicle technologies. It presents a comparison of a scenario with completely successful implementation of Vehicle Technologies Office (VTO) and Fuel Cell Technologies Office (FCTO) technologies (the Program Success case) to a future in whichmore » there is no contribution after Fiscal Year 2017 by the VTO or FCTO to these technologies (the No Program case). Benefits were attributed to individual program technology areas, which included FCTO research and development and the VTO programs of electrification, advanced combustion engines and fuels, and materials technology. Projections for the Program Success case indicate that by 2035, the average fuel economy of on-road, light-duty vehicle stock could be 24% to 30% higher than in the No Program case, while fuel economy for on-road medium- and heavy-duty vehicle stock could be as much as 13% higher. The resulting petroleum savings in 2035 were estimated to be as high as 1.9 million barrels of oil per day, and reductions in greenhouse gas emissions were estimated to be as high as 320 million metric tons of carbon dioxide equivalent per year. Projections of light-duty vehicle adoption indicate that although advanced-technology vehicles may be somewhat more expensive to purchase, the fuel savings result in a net reduction of consumer cost. In 2035, reductions in annual fuel expenditures for vehicles (both light- and heavy-duty) are projected to range from $86 billion to $109 billion (2015$), while the projected increase in new vehicle expenditures in the same year ranges from $6 billion to $24 billion (2015$).« less
Empirical synchronized flow in oversaturated city traffic.
Kerner, Boris S; Hemmerle, Peter; Koller, Micha; Hermanns, Gerhard; Klenov, Sergey L; Rehborn, Hubert; Schreckenberg, Michael
2014-09-01
Based on a study of anonymized GPS probe vehicle traces measured by personal navigation devices in vehicles randomly distributed in city traffic, empirical synchronized flow in oversaturated city traffic has been revealed. It turns out that real oversaturated city traffic resulting from speed breakdown in a city in most cases can be considered random spatiotemporal alternations between sequences of moving queues and synchronized flow patterns in which the moving queues do not occur.
NASA Technical Reports Server (NTRS)
Anderson, Brenda Lindley
2011-01-01
The dramatic journey of the crippled Apollo 13 vehicle has been heavily documented and popularized. Many people know there was an explosion in the service module which caused the vehicle to lose its oxygen supply. Less well known is the set of circumstances which led to the explosion. This paper examines the manufacturing, processing and testing history of oxygen tank #2, detailing the additive effects which caused the oxygen to ignite and to overpressure the tank.
Studies of Cost Effective Structures Design for Future Space Systems - Summary
1968-06-01
low-cost steels , such as HY-150, in high-pressure tankage for lower stages of launch vehicles. Specific implications are: 1) A new, two-stage Earth...relationships for each of these types obviously differ from one to another. In some cases, structures and mechanisms show similar behaviors . The way...necessary before reuse. Research efforts should also be directed at the configuration and pack- aging of expensive launch vehicle components so that
Design and analysis of roll cage
NASA Astrophysics Data System (ADS)
Angadi, Gurusangappa; Chetan, S.
2018-04-01
Wildlife fire fighting vehicles are used to extinguish fires in forests, in this process vehicles face falling objects like rocks, tree branches and other objects. Also due to uneven conditions of the terrain like cliff edges, uneven surfaces etc. makes the vehicle to roll over and these can cause injuries to both the driver and the operator. Roll over of a vehicle is a common incident which makes fatal injuries to the operator and also stands next to the crash accidents. In order to reduce the injury level and continuous roll over of the vehicle it is necessary to equip suitable roll cage according to standards of vehicle. In this present work roll cage for pump operator in wildfire fighting vehicle is designed and analysis is carried out in computer simulated environment when seating position of operator seated outside of the cabin. According to NFPA 1906 standards wildlife fire apparatus, Design and Test procedures that are carried out in Hyperworks maintaining SAE J1194.1983 standards. G load case, roof crush analysis and pendulum impact analysis tests are carried out on roll cage to ensure the saftey of design. These load cases are considerd to satisfy the situation faced in forest terrain. In these test procedures roll cage is analysed for stresses and deformation in various load cases. After recording results these are compared with standards mentioned in SAE J1194.1983.
NASA Technical Reports Server (NTRS)
Smith, Garrett; Philips, Alan
2003-01-01
Three dominant Two Stage To Orbit (TSTO) class architectures were studied: Series Burn (SB), Parallel Bum with crossfeed (PBw/cf), and Parallel Burn, no-crossfeed (PBncf). The study goal was to determine what factors uniquely affect PBncf architectures, how each of these factors interact, and to determine from a performance perspective whether a PBncf vehicle could be competitive with a PBw/cf or a SB vehicle using equivalent technology and assumptions. In all cases, performance was evaluated on a relative basis for a fixed payload and mission by comparing gross and dry vehicle masses of a closed vehicle. Propellant combinations studied were LOX: LH2 propelled booster and orbiter (HH) and LOX: Kerosene booster with LOX: LH2 orbiter (KH). The study observations were: 1) A PBncf orbiter should be throttled as deeply as possible after launch until the staging point. 2) A PBncf TSTO architecture is feasible for systems that stage at mach 7. 2a) HH architectures can achieve a mass growth relative to PBw/cf of <20%. 2b) KH architectures can achieve a mass growth relative to Series Burn of <20%. 3) Center of gravity (CG) control will be a major issue for a PBncf vehicle, due to the low orbiter specific thrust to weight ratio and to the position of the orbiter required to align the nozzle heights at liftoff. 4) Thrust to weight ratios of 1.3 at liftoff and between 1.0 and 0.9 when staging at mach 7 appear to be close to ideal for PBncf vehicles. 5) Performance for HH vehicles was better when staged at mach 7 instead of mach 5. The study suggests possible methods to maximize performance of PBncf vehicle architectures in order to meet mission design requirements.
Han, Guang-Ming; Newmyer, Ashley; Qu, Ming
2015-01-01
Seat belt use is the single most effective way to save lives and reduce injuries in motor vehicle crashes. However, some case reports described seat belt use as a double-edged sword because some injuries are related to seat belt use in motor vehicle crashes. To comprehensively understand the effects of seat belt use, we systemically investigated the association between seat belt use and injuries based on anatomic body region and type of injury in drivers involved in motor vehicle crashes. The injury information was obtained by linking crash reports with hospital discharge data and categorized by using the diagnosis codes based on the Barell injury diagnosis matrix. A total of 10,479 drivers (≥15 years) in passenger vehicles involved in motor vehicle crashes from 2006 to 2011 were included in this study. Seat belt use significantly reduced the proportions of traumatic brain injury (10.4% non-seat belt; 4.1% seat belt) and other head, face, and neck injury (29.3% non-seat belt; 16.6% seat belt) but increased the proportion of spine: thoracic to coccyx injury (17.9% non-seat belt; 35.5% seat belt). Although the proportion of spine: thoracic to coccyx injury was increased in drivers with seat belt use, the severity of injury was decreased, such as fracture (4.2% with seat belt use; 22.0% without seat belt use). Furthermore, the total medical charges decreased due to the change of injury profiles in drivers with seat belt use from a higher percentage of fractures (average cost for per case $26,352) to a higher percentage of sprains and/or strains ($1,897) with spine: thoracic to coccyx injury. This study provide a comprehensive picture for understanding the protective effect of seat belt use on injuries based on anatomic body region and type of injury in drivers involved in motor vehicle crashes.
Gobin, Maya; Hawker, Jeremy; Cleary, Paul; Inns, Thomas; Gardiner, Daniel; Mikhail, Amy; McCormick, Jacquelyn; Elson, Richard; Ready, Derren; Dallman, Tim; Roddick, Iain; Hall, Ian; Willis, Caroline; Crook, Paul; Godbole, Gauri; Tubin-Delic, Drazenka; Oliver, Isabel
2018-05-01
We investigated a large outbreak of Escherichia coli O157 in the United Kingdom (UK) with 165 cases between 31 May and 29 July 2016. No linked cases were reported in other countries. Cases were predominately female (n = 128) and adult (n = 150), 66 attended hospital and nine had features of haemorrhagic uraemic syndrome. A series of epidemiological studies (case-control, case-case, ingredients-based and venue-based studies) and supply chain investigations implicated mixed salad leaves from Supplier A as the likely outbreak vehicle. Whole genome sequencing (WGS) indicated a link with strains from the Mediterranean and informed the outbreak control team to request that Supplier A cease distributing salad leaves imported from Italy. Microbiological tests of samples of salad leaves from Supplier A were negative. We were unable to confirm the source of contamination or the contaminated constituent leaf although our evidence pointed to red batavia received from Italy as the most likely vehicle. Variations in Shiga toxin-producing E. coli surveillance and diagnosis may have prevented detection of cases outside the UK and highlights a need for greater standardisation. WGS was useful in targeting investigations, but greater coverage across Europe is needed to maximise its potential.
Mook, P; McCormick, J; Kanagarajah, S; Adak, G K; Cleary, P; Elson, R; Gobin, M; Hawker, J; Inns, T; Sinclair, C; Trienekens, S C M; Vivancos, R; McCarthy, N D
2018-03-01
Established methods of recruiting population controls for case-control studies to investigate gastrointestinal disease outbreaks can be time consuming, resulting in delays in identifying the source or vehicle of infection. After an initial evaluation of using online market research panel members as controls in a case-control study to investigate a Salmonella outbreak in 2013, this method was applied in four further studies in the UK between 2014 and 2016. We used data from all five studies and interviews with members of each outbreak control team and market research panel provider to review operational issues, evaluate risk of bias in this approach and consider methods to reduce confounding and bias. The investigators of each outbreak reported likely time and cost savings from using market research controls. There were systematic differences between case and control groups in some studies but no evidence that conclusions on the likely source or vehicle of infection were incorrect. Potential selection biases introduced by using this sampling frame and the low response rate are unclear. Methods that might reduce confounding and some bias should be balanced with concerns for overmatching. Further evaluation of this approach using comparisons with traditional methods and population-based exposure survey data is recommended.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yuche; Young, Stanley; Gonder, Jeff
This study estimates the range of fuel and emissions impact of an automated-vehicle (AV) based transit system that services campus-based developments, termed an automated mobility district (AMD). The study develops a framework to quantify the fuel consumption and greenhouse gas (GHG) emission impacts of a transit system comprised of AVs, taking into consideration average vehicle fleet composition, fuel consumption/GHG emission of vehicles within specific speed bins, and the average occupancy of passenger vehicles and transit vehicles. The framework is exercised using a previous mobility analysis of a personal rapid transit (PRT) system, a system which shares many attributes with envisionedmore » AV-based transit systems. Total fuel consumption and GHG emissions with and without an AMD are estimated, providing a range of potential system impacts on sustainability. The results of a previous case study based of a proposed implementation of PRT on the Kansas State University (KSU) campus in Manhattan, Kansas, serves as the basis to estimate personal miles traveled supplanted by an AMD at varying levels of service. The results show that an AMD has the potential to reduce total system fuel consumption and GHG emissions, but the amount is largely dependent on operating and ridership assumptions. The study points to the need to better understand ride-sharing scenarios and calls for future research on sustainability benefits of an AMD system at both vehicle and system levels.« less
Genetic Algorithm and Tabu Search for Vehicle Routing Problems with Stochastic Demand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ismail, Zuhaimy, E-mail: zuhaimyi@yahoo.com, E-mail: irhamahn@yahoo.com; Irhamah, E-mail: zuhaimyi@yahoo.com, E-mail: irhamahn@yahoo.com
2010-11-11
This paper presents a problem of designing solid waste collection routes, involving scheduling of vehicles where each vehicle begins at the depot, visits customers and ends at the depot. It is modeled as a Vehicle Routing Problem with Stochastic Demands (VRPSD). A data set from a real world problem (a case) is used in this research. We developed Genetic Algorithm (GA) and Tabu Search (TS) procedure and these has produced the best possible result. The problem data are inspired by real case of VRPSD in waste collection. Results from the experiment show the advantages of the proposed algorithm that aremore » its robustness and better solution qualities.« less
Discrete tyre model application for evaluation of vehicle limit handling performance
NASA Astrophysics Data System (ADS)
Siramdasu, Y.; Taheri, S.
2016-11-01
The goal of this study is twofold, first, to understand the transient and nonlinear effects of anti-lock braking systems (ABS), road undulations and driving dynamics on lateral performance of tyre and second, to develop objective handling manoeuvres and respective metrics to characterise these effects on vehicle behaviour. For studying the transient and nonlinear handling performance of the vehicle, the variations of relaxation length of tyre and tyre inertial properties play significant roles [Pacejka HB. Tire and vehicle dynamics. 3rd ed. Butterworth-Heinemann; 2012]. To accurately simulate these nonlinear effects during high-frequency vehicle dynamic manoeuvres, requires a high-frequency dynamic tyre model (? Hz). A 6 DOF dynamic tyre model integrated with enveloping model is developed and validated using fixed axle high-speed oblique cleat experimental data. Commercially available vehicle dynamics software CarSim® is used for vehicle simulation. The vehicle model was validated by comparing simulation results with experimental sinusoidal steering tests. The validated tyre model is then integrated with vehicle model and a commercial grade rule-based ABS model to perform various objective simulations. Two test scenarios of ABS braking in turn on a smooth road and accelerating in a turn on uneven and smooth roads are considered. Both test cases reiterated that while the tyre is operating in the nonlinear region of slip or slip angle, any road disturbance or high-frequency brake torque input variations can excite the inertial belt vibrations of the tyre. It is shown that these inertial vibrations can directly affect the developed performance metrics and potentially degrade the handling performance of the vehicle.
Brown, Michael J; Williams, Michael D; Nelson, Matthew A; Werley, Kenneth A
2015-01-01
The Quick Urban and Industrial Complex (QUIC) plume modeling system is used to explore how the transport and dispersion of vehicle emissions in cities are impacted by the presence of buildings. Using downtown Philadelphia as a test case, notional vehicle emissions of gases and particles are specified as line source releases on a subset of the east-west and north-south streets. Cases were run in flat terrain and with 3D buildings present in order to show the differences in the model-computed outdoor concentration fields with and without buildings present. The QUIC calculations show that buildings result in regions with much higher concentrations and other areas with much lower concentrations when compared to the flat-earth case. On the roads with vehicle emissions, street-level concentrations were up to a factor of 10 higher when buildings were on either side of the street as compared to the flat-earth case due to trapping of pollutants between buildings. However, on roads without vehicle emissions and in other open areas, the concentrations were up to a factor of 100 times smaller as compared to the flat earth case because of vertical mixing of the vehicle emissions to building height in the cavity circulation that develops on the downwind side of unsheltered buildings. QUIC was also used to calculate infiltration of the contaminant into the buildings. Indoor concentration levels were found to be much lower than outdoor concentrations because of deposition onto indoor surfaces and particulate capture for buildings with filtration systems. Large differences in indoor concentrations from building to building resulted from differences in leakiness, air handling unit volume exchange rates, and filter type and for naturally ventilated buildings, whether or not the building was sheltered from the prevailing wind by a building immediately upwind.
Case Study - Propane School Bus Fleets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laughlin, M; Burnham, A.
As part of the U.S. Department of Energy’s (DOE’s) effort to deploy transportation technologies that reduce U.S. dependence on imported petroleum, this study examines five school districts, one in Virginia and four in Texas, successful use of propane school buses. These school districts used school buses equipped with the newly developed liquid propane injection system that improves vehicle performance. Some of the school districts in this study saved nearly 50% on a cost per mile basis for fuel and maintenance relative to diesel. Using Argonne National Laboratory’s Alternative Fuel Life-Cycle Environmental and Economic Transportation (AFLEET) Tool developed for the DOE’smore » Clean Cities program to help Clean Cities stakeholders estimate petroleum use, greenhouse gas (GHG) emissions, air pollutant emissions and cost of ownership of light-duty and heavy-duty vehicles, the results showed payback period ranges from 3—8 years, recouping the incremental cost of the vehicles and infrastructure. Overall, fuel economy for these propane vehicles is close to that of displaced diesel vehicles, on an energy-equivalent basis. In addition, the 110 propane buses examined demonstrated petroleum displacement, 212,000 diesel gallon equivalents per year, and GHG benefits of 770 tons per year.« less
NASA Technical Reports Server (NTRS)
Hollis, Brian R.; Hollingsworth, Kevin E.
2014-01-01
Aeroheating data on mid lift-to-drag ratio entry vehicle configurations has been obtained through hypersonic wind tunnel testing. Vehicles of this class have been proposed for high-mass Mars missions, such as sample return and crewed exploration, for which the conventional sphere-cone entry vehicle geometries of previous Mars missions are insufficient. Several configurations were investigated, including elliptically-blunted cylinders with both circular and elliptical cross sections, biconic geometries based on launch vehicle dual-use shrouds, and parametrically-optimized analytic geometries. Testing was conducted at Mach 6 over a range of Reynolds numbers sufficient to generate laminar, transitional, and turbulent flow. Global aeroheating data were obtained using phosphor thermography. Both stream-wise and cross-flow transition occured on different configurations. Comparisons were made with laminar and turbulent computational predictions generated with an algebraic turbulence model. Predictions were generally in good agreement in regions of laminar or fully-turbulent flow; however for transitional cases, the lack of a transition onset prediction capability produced less accurate comparisons. The data obtained in this study are intended to be used for prelimary mission design studies and the development and validation of computational methods.
Zhang, Qingyu; Fan, Juwang; Yang, Weidong; Chen, Bixin; Zhang, Lijuan; Liu, Jiaoyu; Wang, Jingling; Zhou, Chunyao; Chen, Xuan
2017-07-01
Vehicle deterioration and technological change influence emission factors (EFs). In this study, the impacts of vehicle deterioration and emission standards on EFs of regulated pollutants (carbon monoxide [CO], hydrocarbon [HC], and nitrogen oxides [NO x ]) for gasoline light-duty trucks (LDTs) were investigated according to the inspection and maintenance (I/M) data using a chassis dynamometer method. Pollutant EFs for LDTs markedly varied with accumulated mileages and emission standards, and the trends of EFs are associated with accumulated mileages. In addition, the study also found that in most cases, the median EFs of CO, HC, and NO x are higher than those of basic EFs in the International Vehicle Emissions (IVE) model; therefore, the present study provides correction factors for the IVE model relative to the corresponding emission standards and mileages. Currently, vehicle emissions are great contributors to air pollution in cities, especially in developing countries. Emission factors play a key role in creating emission inventory and estimating emissions. Deterioration represented by vehicle age and accumulated mileage and changes of emission standards markedly influence emission factors. In addition, the results provide collection factors for implication in the IVE model in the region levels.
Grahn, M; Azar, C; Williander, M I; Anderson, J E; Mueller, S A; Wallington, T J
2009-05-01
The regionalized Global Energy Transition (GET-R 6.0) model has been modified to include a detailed description of light-duty vehicle options and used to investigate the potential impact of carbon capture and storage (CCS) and concentrating solar power (CSP) on cost-effective fuel/vehicle technologies in a carbon-constrained world. Total CO2 emissions were constrained to achieve stabilization at 400-550 ppm, by 2100, at lowesttotal system cost The dominantfuel/vehicle technologies varied significantly depending on CO2 constraint future cost of vehicle technologies, and availability of CCS and CSP. For many cases, no one technology dominated on a global scale. CCS provides relatively inexpensive low-CO2 electricity and heatwhich prolongs the use of traditional ICEVs. CSP displaces fossil fuel derived electricity, prolongs the use of traditional ICEVs, and promotes electrification of passenger vehicles. In all cases considered, CCS and CSP availability had a major impact on the lowest cost fuel/vehicle technologies, and alternative fuels are needed in response to expected dwindling oil and natural gas supply potential by the end of the century.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mitchell, George
VICE 2.0 is the second generation of the VICE financial model developed by the National Renewable Energy Laboratory for fleet managers to assess the financial soundness of converting their fleets to run on CNG. VICE 2.0 uses a number of variables for infrastructure and vehicles to estimate the business case for decision-makers when considering CNG as a vehicle fuel. Enhancements in version 2.0 include the ability to select the project type (vehicles and infrastructure or vehicle acquisitions only), and to decouple vehicle acquisition from the infrastructure investment, so the two investments may be made independently. Outputs now include graphical presentationsmore » of investment cash flow, payback period (simple and discounted), petroleum displacement (annual and cumulative), and annual greenhouse gas reductions. Also, the Vehicle Data are now built around several common conventionally fueled (gasoline and diesel) fleet vehicles. Descriptions of the various model sections and available inputs follow. Each description includes default values for the base-case business model, which was created so economic sensitivities can be investigated by altering various project parameters one at a time.« less
Who Sits Where? Infrastructure-Free In-Vehicle Cooperative Positioning via Smartphones
He, Zongjian; Cao, Jiannong; Liu, Xuefeng; Tang, Shaojie
2014-01-01
Seat-level positioning of a smartphone in a vehicle can provide a fine-grained context for many interesting in-vehicle applications, including driver distraction prevention, driving behavior estimation, in-vehicle services customization, etc. However, most of the existing work on in-vehicle positioning relies on special infrastructures, such as the stereo, cigarette lighter adapter or OBD (on-board diagnostic) adapter. In this work, we propose iLoc, an infrastructure-free, in-vehicle, cooperative positioning system via smartphones. iLoc does not require any extra devices and uses only embedded sensors in smartphones to determine the phones' seat-level locations in a car. In iLoc, in-vehicle smartphones automatically collect data during certain kinds of events and cooperatively determine the relative left/right and front/back locations. In addition, iLoc is tolerant to noisy data and possible sensor errors. We evaluate the performance of iLoc using experiments conducted in real driving scenarios. Results show that the positioning accuracy can reach 90% in the majority of cases and around 70% even in the worst-cases. PMID:24984062
NASA Astrophysics Data System (ADS)
Takahashi, Toshimichi
2018-05-01
The tyre model which formerly developed by the author et al. and describes the tyre transient responses of side force and aligning moment under the time-varying vertical force was implemented to the vehicle dynamics simulation software and the influence of tyre side force transient property on the vehicle behaviour was investigated. The vehicle responses with/without tyre transient property on sinusoidally undulated road surfaces were simulated and compared. It was found that the average lateral acceleration of the vehicle at the sinusoidal steering wheel angle input decreases on the undulated road of long wavelength (3 m) for both cases, but when the wavelength becomes shorter (1 m), the average lateral acceleration increases only in the case that the transient property is considered. The cause of those changes is explained by using the tyre-related variables. Also the steady-state turning behaviour of the vehicle on undulated roads are shown and discussed.
Evaluation the course of the vehicle braking process in case of hydraulic circuit malfunction
NASA Astrophysics Data System (ADS)
Szczypiński-Sala, W.; Lubas, J.
2016-09-01
In the paper, the results of the research were discussed, the aim of which was the evaluation of the vehicle braking performance efficiency and the course of this process with regard to the dysfunction which may occur in braking hydraulic circuit. As part of the research, on-road tests were conducted. During the research, the delay of the vehicle when braking was measured with the use of the set of sensors placed in the parallel and the perpendicular axis of the vehicle. All the tests were conducted on the same flat section of asphalt road with wet surface. Conditions of diminished tire-to-road adhesion were chosen in order to force the activity of anti-lock braking system. The research was conducted comparatively for the vehicle with acting anti-lock braking system and subsequently for the vehicle without the system. In both cases, there was a subsequent evaluation of the course of braking with efficient braking system and with the dysfunction of hydraulic circuit.
Zero-moment point determination of worst-case manoeuvres leading to vehicle wheel lift
NASA Astrophysics Data System (ADS)
Lapapong, S.; Brown, A. A.; Swanson, K. S.; Brennan, S. N.
2012-01-01
This paper proposes a method to evaluate vehicle rollover propensity based on a frequency-domain representation of the zero-moment point (ZMP). Unlike other rollover metrics such as the static stability factor, which is based on the steady-state behaviour, and the load transfer ratio, which requires the calculation of tyre forces, the ZMP is based on a simplified kinematic model of the vehicle and the analysis of the contact point of the vehicle relative to the edge of the support polygon. Previous work has validated the use of the ZMP experimentally in its ability to predict wheel lift in the time domain. This work explores the use of the ZMP in the frequency domain to allow a chassis designer to understand how operating conditions and vehicle parameters affect rollover propensity. The ZMP analysis is then extended to calculate worst-case sinusoidal manoeuvres that lead to untripped wheel lift, and the analysis is tested across several vehicle configurations and compared with that of the standard Toyota J manoeuvre.
Traumatic brain injuries in children: A hospital-based study in Nigeria.
Udoh, David O; Adeyemo, Adebolajo A
2013-01-01
Traumatic Brain Injury (TBI) is a significant cause of morbidity and mortality worldwide. Our previous studies showed a high frequency of motor vehicle accidents among neurosurgical patients. However, there is a dearth of data on head injuries in children in Nigeria. To determine the epidemiology of paediatric traumatic brain injuries. This is a prospective analysis of paediatric head trauma at the University of Benin Teaching Hospital, a major referral centre for all traumatic brain injuries in Nigeria between October 2006 and September 2011. We studied the demographic, clinical and radiological data and treatment outcomes. Data was analysed using statistical package for the social sciences (SPSS) 16.0. We managed 127 cases of paediatric head injuries, 65 boys and 62 girls representing 13% of all head injuries managed over the 5-year period. They were aged 3 months to 17 years. The mean age was 7.4 years (median 7 years) with peak incidence occurring at 6-8 years i.e. 31 (24.4%) cases. Motor vehicle accidents resulted in 67.7%, falls 14% and violence 7%. The most frequent computed tomography finding was intracerebral haemorrhage. Mean duration of hospitalization was 18 days (median 11 days). Eleven patients died, mortality correlating well with severity and the presence of intracerebral haematoma. Head injuries in children are due to motor vehicle and motor vehicle-related accidents. Hence, rational priorities for prevention of head injuries in children should include prevention of vehicular, especially pedestrian, accidents in developing countries.
Rudisill, Toni M; Zhu, Motao; Davidov, Danielle; Leann Long, D; Sambamoorthi, Usha; Abate, Marie; Delagarza, Vincent
2016-03-15
The current generation of older adults reports a higher lifetime prevalence of prescription, over-the-counter, and recreational drug use. The purpose of this analysis is to characterize the drug usage and determine the risk of motor vehicle collision associated with individual medications in a population of drivers ≥ 65 years. A case-crossover study was conducted at West Virginia University Healthcare's facilities using data obtained from the electronic health records (n = 611) of drivers ≥ 65 years admitted for medical treatment following a motor vehicle collision which occurred between Jan. 1, 2009 and June 30, 2014. Patients' medication usage 14 days before collision were matched and compared to their medication usage during four control periods prior to collision. Odds ratios were then calculated for the most prevalent individual medications and pharmaceutical sub-classes using conditional logistic regression. Analgesic, cardiovascular and gastrointestinal medicines were common. Few drivers tested positive for either licit or illicit drugs. Of those testing positive for drugs, benzodiazepines and opiates were prevalent. Drivers consuming Tramadol (adjusted OR 11.41; 95% CI 1.27, 102.15) were at a significantly increased risk of motor vehicle collision. Older adult drivers who have a prescription for this medication may need to be aware of the potential risk. Further research is necessary in a larger, more nationally representative population.
Lardelli-Claret, Pablo; Luna-Del-Castillo, Juan de Dios; Jiménez-Moleón, José Juan; Rueda-Domínguez, Trinidad; García-Martín, Miguel; Femia-Marzo, Pedro; Bueno-Cavanillas, Aurora
2003-08-01
To assess the strength of association of main driver-dependent risk factors with the risk of causing a collision between vehicles in Spain, from 1990 to 1999. The data for this paired-by-collision, case-control study were obtained from the Spanish Dirección General de Tráfico traffic crash database. The study included all 220284 collisions involving two or more vehicles with four or more wheels, in which only one of the drivers involved committed an infraction. Infractor drivers comprised the case group; noninfractor drivers involved in the same collision were their corresponding paired controls. All driver-dependent factors were associated with the risk of causing a collision. The highest adjusted odds ratio estimates were obtained for sleepiness (64.35; CI, 45.12-91.79), inappropriate speed (28.33; CI, 26.37-30.44), and driving under the influence of alcohol with a positive breath test (22.32; CI, 19.64-25.37). An increase in the number of years in possession of a driving license showed a protective effect, albeit the strength of the effect decreased as age increased. Our results emphasize the urgent need to implement strategies aimed mainly at controlling speeding, sleepiness, and alcohol consumption before driving-the main driver-dependent risk factors for causing a vehicle collision.
Vehicles instability criteria for flood risk assessment of a street network
NASA Astrophysics Data System (ADS)
Arrighi, Chiara; Huybrechts, Nicolas; Ouahsine, Abdellatif; Chassé, Patrick; Oumeraci, Hocine; Castelli, Fabio
2016-05-01
The mutual interaction between floods and human activity is a process, which has been evolving over history and has shaped flood risk pathways. In developed countries, many events have illustrated that the majority of the fatalities during a flood occurs in a vehicle, which is considered as a safe shelter but it may turn into a trap for several combinations of water depth and velocity. Thus, driving a car in floodwaters is recognized as the most crucial aggravating factor for people safety. On the other hand, the entrainment of vehicles may locally cause obstructions to the flow and induce the collapse of infrastructures. Flood risk to vehicles can be defined as the combination of the probability of a vehicle of being swept away (i.e. the hazard) and the actual traffic/parking density, i.e. the vulnerability. Hazard for vehicles can be assessed through the spatial identification and mapping of the critical conditions for vehicles incipient motion. This analysis requires a flood map with information on water depth and velocity and consistent instability criteria accounting for flood and vehicles characteristics. Vulnerability is evaluated thanks to the road network and traffic data. Therefore, vehicles flood risk mapping can support people's education and management practices in order to reduce the casualties. In this work, a flood hazard classification for vehicles is introduced and an application to a real case study is presented and discussed.
Railway vehicle body structures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1985-01-01
The strength and durability of railway vehicle structures is a major topic of engineering research and design. To reflect this importance the Railway Division of the Institution of Mechanical Engineers organised a conference to discuss all matters relating to railway vehicle design. This book presents the papers discussed in that conference. The contents include: Vehicle body design and the UIC's international contribution; LUL prototype 1986 stock - body structure; vehicle structure for the intermediate capacity transmit system vehicles; car body technology of advanced light rapid transit vehicles; concepts, techniques and experience in the idealization of car body structures for finitemore » element analysis; Calcutta metropolitan railway; design for a lightweight diesel multiple unit body; the design of lightweight inter-city coal structures; the BREL international coach body shell structure; new concepts and design techniques versus material standards; structures of BR diesel electric freight locomotives; structural design philosophy for electric locomotives; suspension design for a locomotive with low structural frequencies; freight wagon structures; a finite element study of coal bodyside panels including the effects of joint flexibility; a fresh approach to the problem of car body design strength; energy absorption in automatic couplings and draw gear; passenger vehicle design loads and structural crashworthiness; design of the front part of railway vehicles (in case of frontal impact); the development of a theoretical technique for rail vehicle structural crashworthiness.« less
Motor vehicle fatalities among oil and gas extraction workers.
Retzer, Kyla D; Hill, Ryan D; Pratt, Stephanie G
2013-03-01
Motor vehicle crashes are the leading cause of work-related fatality in the U.S. as well as in the oil and gas extraction industry. This study describes the characteristics of motor vehicle-related fatalities in the oil and gas extraction industry using data from the U.S. Bureau of Labor Statistics' Census of Fatal Occupational Injuries. It compares the risk of dying in a motor vehicle crash in this industry to other major industries and among different types and sizes of oil and gas extraction companies. There were 202 oil and gas extraction workers who died in a work-related motor vehicle crash from 2003 to 2009. The motor vehicle fatality rate for workers in this industry was 8.5 times that of all private wage and salary workers (7.6 vs. 0.9, p<.0001). Workers from small oil and gas establishments (<20 workers) and workers from well-servicing companies were at greatest risk of dying in a motor vehicle crash. Pick-up trucks were the most frequent type of vehicle occupied by the fatally injured worker (n=104, 51.5%). Safety belt non-use was identified in 38.1% (n=77) of the cases. Increased focus on motor vehicle safety in this industry is needed, in particular among small establishments. Extraction workers who drive light duty vehicles need to be a specific focus. Published by Elsevier Ltd.
A Summary of the NASA Design Environment for Novel Vertical Lift Vehicles (DELIVER) Project
NASA Technical Reports Server (NTRS)
Theodore, Colin R.
2018-01-01
The number of new markets and use cases being developed for vertical take-off and landing vehicles continues to explode, including the highly publicized urban air taxi and package deliver applications. There is an equally exploding variety of novel vehicle configurations and sizes that are being proposed to fill these new market applications. The challenge for vehicle designers is that there is currently no easy and consistent way to go from a compelling mission or use case to a vehicle that is best configured and sized for the particular mission. This is because the availability of accurate and validated conceptual design tools for these novel types and sizes of vehicles have not kept pace with the new markets and vehicles themselves. The Design Environment for Novel Vertical Lift Vehicles (DELIVER) project was formulated to address this vehicle design challenge by demonstrating the use of current conceptual design tools, that have been used for decades to design and size conventional rotorcraft, applied to these novel vehicle types, configurations and sizes. In addition to demonstrating the applicability of current design and sizing tools to novel vehicle configurations and sizes, DELIVER also demonstrated the addition of key transformational technologies of noise, autonomy, and hybrid-electric and all-electric propulsion into the vehicle conceptual design process. Noise is key for community acceptance, autonomy and the need to operate autonomously are key for efficient, reliable and safe operations, and electrification of the propulsion system is a key enabler for these new vehicle types and sizes. This paper provides a summary of the DELIVER project and shows the applicability of current conceptual design and sizing tools novel vehicle configurations and sizes that are being proposed for urban air taxi and package delivery type applications.
Launch Vehicle Design and Optimization Methods and Priority for the Advanced Engineering Environment
NASA Technical Reports Server (NTRS)
Rowell, Lawrence F.; Korte, John J.
2003-01-01
NASA's Advanced Engineering Environment (AEE) is a research and development program that will improve collaboration among design engineers for launch vehicle conceptual design and provide the infrastructure (methods and framework) necessary to enable that environment. In this paper, three major technical challenges facing the AEE program are identified, and three specific design problems are selected to demonstrate how advanced methods can improve current design activities. References are made to studies that demonstrate these design problems and methods, and these studies will provide the detailed information and check cases to support incorporation of these methods into the AEE. This paper provides background and terminology for discussing the launch vehicle conceptual design problem so that the diverse AEE user community can participate in prioritizing the AEE development effort.
NASA Technical Reports Server (NTRS)
Smith, Garrett; Phillips, Alan
2002-01-01
There are currently three dominant TSTO class architectures. These are Series Burn (SB), Parallel Burn with crossfeed (PBw/cf), and Parallel Burn without crossfeed (PBncf). The goal of this study was to determine what factors uniquely affect PBncf architectures, how each of these factors interact, and to determine from a performance perspective whether a PBncf vehicle could be competitive with a PBw/cf or SB vehicle using equivalent technology and assumptions. In all cases, performance was evaluated on a relative basis for a fixed payload and mission by comparing gross and dry vehicle masses of a closed vehicle. Propellant combinations studied were LOX: LH2 propelled orbiter and booster (HH) and LOX: Kerosene booster with LOX: LH2 orbiter (KH). The study conclusions were: 1) a PBncf orbiter should be throttled as deeply as possible after launch until the staging point. 2) a detailed structural model is essential to accurate architecture analysis and evaluation. 3) a PBncf TSTO architecture is feasible for systems that stage at mach 7. 3a) HH architectures can achieve a mass growth relative to PBw/cf of < 20%. 3b) KH architectures can achieve a mass growth relative to Series Burn of < 20%. 4) center of gravity (CG) control will be a major issue for a PBncf vehicle, due to the low orbiter specific thrust to weight ratio and to the position of the orbiter required to align the nozzle heights at liftoff. 5 ) thrust to weight ratios of 1.3 at liftoff and between 1.0 and 0.9 when staging at mach 7 appear to be close to ideal for PBncf vehicles. 6) performance for all vehicles studied is better when staged at mach 7 instead of mach 5. The study showed that a Series Burn architecture has the lowest gross mass for HH cases, and has the lowest dry mass for KH cases. The potential disadvantages of SB are the required use of an air-start for the orbiter engines and potential CG control issues. A Parallel Burn with crossfeed architecture solves both these problems, but the mechanics of a large bipropellant crossfeed system pose significant technical difficulties. Parallel Burn without crossfeed vehicles start both booster and orbiter engines on the ground and thus avoid both the risk of orbiter air-start and the complexity of a crossfeed system. The drawback is that the orbiter must use 20% to 35% of its propellant before reaching the staging point. This induces a weight penalty in the orbiter in order to carry additional propellant, which causes a further weight penalty in the booster to achieve the same staging point. One way to reduce the orbiter propellant consumption during the first stage is to throttle down the orbiter engines as much as possible. Another possibility is to use smaller or fewer engines. Throttling the orbiter engines soon after liftoff minimizes CG control problems due to a low orbiter liftoff thrust, but may result in an unnecessarily high orbiter thrust after staging. Reducing the number or size of engines size may cause CG control problems and drift at launch. The study suggested possible methods to maximize performance of PBncf vehicle architectures in order to meet mission design requirements.
Richens, D; Kotidis, K; Neale, M; Oakley, C; Fails, A
2003-02-01
The true incidence and survivability of blunt traumatic aortic rupture following road traffic accidents in the UK is unclear. The objective of this study was to determine the extent of blunt traumatic aortic rupture in the UK after road traffic accidents and the conditions under which it occurs. Data for the study was obtained from the Co-operative Crash Injury Study database. Road traffic accidents that happened between 1992 and 1999 and included in the Co-operative Crash Injury Study database were retrospectively investigated. A total of 8285 vehicles carrying 14,435 occupants were involved in 7067 accidents. There were 132 cases of blunt traumatic aortic rupture, of which the scene survival was 9% and the overall mortality was 98%. Twenty-one percent of all fatalities had blunt traumatic aortic rupture (130/613). Twenty-nine percent were due to frontal impacts and 44% were due to side impacts. Twelve percent of the blunt traumatic aortic rupture cases in frontal vehicle impacts were wearing seat belts and had airbag protection and 19% had no restraint mechanism. The Equivalent Test Speed of the accident vehicles, (where equivalent test speed provides an estimate of the vehicle impact severity and not an estimate of the vehicle speed at the time of the accident), ranged from 30 to 110 km/h in frontal impacts and from 15 to 82 km/h in side impacts. Blunt traumatic aortic rupture carries a high mortality and occurred in 21% of car occupant deaths in this sample of road traffic accidents. Impact scenarios varied but were most common from the side. The use of an airbag or seat belt does not eliminate risk. The injury can occur at low severity impacts particularly in side impact. Copyright 2002 Elsevier Science B.V.
Medication use and the risk of motor vehicle collisions among licensed drivers: A systematic review
Rudisill, Toni M.; Zhu, Motao; Kelley, George A.; Pilkerton, Courtney; Rudisill, Brandon R.
2016-01-01
Objectives Driving under the influence of prescription and over-the-counter medication is a growing public health concern. A systematic review of the literature was performed to investigate which specific medications were associated with increased risk of motor vehicle collision (MVC). Methods The a priori inclusion criteria were: 1) studies published from English-language sources on or after January 1, 1960, 2) licensed drivers 15 years of age and older, 3) peer-reviewed publications, master's theses, doctoral dissertations, and conference papers, 4) studies limited to randomized control trials, cohort studies, case-control studies, or case-control type studies 5) outcome measure reported for at least one specific medication, 6) outcome measure reported as the odds or risk of a motor vehicle collision. Fourteen databases were examined along with hand-searching. Independent, dual selection of studies and data abstraction was performed. Results Fifty-three medications were investigated by 27 studies included in the review. Fifteen (28.3%) were associated with an increased risk of MVC. These included Buprenorphine, Codeine, Dihydrocodeine, Methadone, Tramadol, Levocitirizine, Diazepam, Flunitrazepam, Flurazepam, Lorazepam, Temazepam, Triazolam, Carisoprodol, Zolpidem, and Zopiclone. Conclusions Several medications were associated with an increased risk of MVC and decreased driving ability. The associations between specific medication use and the increased risk of MVC and/or affected driving ability are complex. Future research opportunities are plentiful and worthy of such investigation. PMID:27569655
Marijuana use and car crash injury.
Blows, Stephanie; Ivers, Rebecca Q; Connor, Jennie; Ameratunga, Shanthi; Woodward, Mark; Norton, Robyn
2005-05-01
To investigate the relationship between marijuana use prior to driving, habitual marijuana use and car crash injury. Population based case-control study in Auckland, New Zealand. Case vehicles were all cars involved in crashes in which at least one occupant was hospitalized or killed anywhere in the Auckland region, and control vehicles were a random sample of cars driving on Auckland roads. The drivers of 571 case and 588 control vehicles completed a structured interview. Self reported marijuana use in the 3 hours prior to the crash/survey and habitual marijuana use over the previous 12 months were recorded, along with a range of other variables potentially related to crash risk. The main outcome measure was hospitalization or death of a vehicle occupant due to car crash injury. Acute marijuana use was significantly associated with car crash injury, after controlling for the confounders age, gender, ethnicity, education level, passenger carriage, driving exposure and time of day (OR 3.9, 95% CI 1.2-12.9). However, after adjustment for these confounders plus other risky driving at the time of the crash (blood alcohol concentration, seat-belt use, travelling speed and sleepiness score), the effect of acute marijuana intake was no longer significant (OR 0.8, 95% CI 0.2-3.3). There was a strong significant association between habitual use and car crash injury after adjustment for all the above confounders plus acute use prior to driving (OR 9.5, 95% CI 2.8-32.3). This population-based case-control study indicates that habitual use of marijuana is strongly associated with car crash injury. The nature of the relationship between marijuana use and risk-taking is unclear and needs further research. The prevalence of marijuana use in this driving population was low, and acute use was associated with habitual marijuana use, suggesting that intervention strategies may be more effective if they are targeted towards high use groups.
Energy and Economic Impacts of Projected Freight Transportation Improvements
DOT National Transportation Integrated Search
1977-05-01
This study examines current and future energy impacts for each major freight mode, by commodity, and, in many cases, by vehicle types. It also discusses potential economic impacts of these anticipated changes. The study is limited to intercity freigh...
DOT National Transportation Integrated Search
1999-09-01
This is one of seven studies exploring processes for developing Intelligent Transportation Systems (ITS) architectures for regional, statewide, or commercial vehicle applications. This study was prepared for a broad-based, non-technical audience. The...
Moving beyond teen crash fatality statistics : the go-team study.
DOT National Transportation Integrated Search
2013-04-08
Despite a trend of decreasing teen fatalities due to motor vehicle crashes over the past decade, they remain the leading cause : of adolescent fatalities in Iowa. The purpose of this study was to create detailed case studies of each fatal motor vehic...
DOT National Transportation Integrated Search
1995-07-01
The primary focus of this study was to emphasize transit system energy characteristics by examining the vehicle characteristics, right-of-way charactertistics and the operational aspects of the services. The objectives : of this study were to become ...
DOT National Transportation Integrated Search
1999-09-01
This is one of seven studies exploring processes for developing Intelligent Transportation Systems (ITS) architectures for regional, statewide, or commercial vehicle applications. This study was prepared for a broad-based, non-technical audience. In ...
Zangenehpour, Sohail; Strauss, Jillian; Miranda-Moreno, Luis F; Saunier, Nicolas
2016-01-01
Cities in North America have been building bicycle infrastructure, in particular cycle tracks, with the intention of promoting urban cycling and improving cyclist safety. These facilities have been built and expanded but very little research has been done to investigate the safety impacts of cycle tracks, in particular at intersections, where cyclists interact with turning motor-vehicles. Some safety research has looked at injury data and most have reached the conclusion that cycle tracks have positive effects of cyclist safety. The objective of this work is to investigate the safety effects of cycle tracks at signalized intersections using a case-control study. For this purpose, a video-based method is proposed for analyzing the post-encroachment time as a surrogate measure of the severity of the interactions between cyclists and turning vehicles travelling in the same direction. Using the city of Montreal as the case study, a sample of intersections with and without cycle tracks on the right and left sides of the road were carefully selected accounting for intersection geometry and traffic volumes. More than 90h of video were collected from 23 intersections and processed to obtain cyclist and motor-vehicle trajectories and interactions. After cyclist and motor-vehicle interactions were defined, ordered logit models with random effects were developed to evaluate the safety effects of cycle tracks at intersections. Based on the extracted data from the recorded videos, it was found that intersection approaches with cycle tracks on the right are safer than intersection approaches with no cycle track. However, intersections with cycle tracks on the left compared to no cycle tracks seem to be significantly safer. Results also identify that the likelihood of a cyclist being involved in a dangerous interaction increases with increasing turning vehicle flow and decreases as the size of the cyclist group arriving at the intersection increases. The results highlight the important role of cycle tracks and the factors that increase or decrease cyclist safety. Results need however to be confirmed using longer periods of video data. Copyright © 2015 Elsevier Ltd. All rights reserved.
Estimating Vehicle Fuel Consumption and Emissions Using GPS Big Data
Kan, Zihan; Zhang, Xia
2018-01-01
The energy consumption and emissions from vehicles adversely affect human health and urban sustainability. Analysis of GPS big data collected from vehicles can provide useful insights about the quantity and distribution of such energy consumption and emissions. Previous studies, which estimated fuel consumption/emissions from traffic based on GPS sampled data, have not sufficiently considered vehicle activities and may have led to erroneous estimations. By adopting the analytical construct of the space-time path in time geography, this study proposes methods that more accurately estimate and visualize vehicle energy consumption/emissions based on analysis of vehicles’ mobile activities (MA) and stationary activities (SA). First, we build space-time paths of individual vehicles, extract moving parameters, and identify MA and SA from each space-time path segment (STPS). Then we present an N-Dimensional framework for estimating and visualizing fuel consumption/emissions. For each STPS, fuel consumption, hot emissions, and cold start emissions are estimated based on activity type, i.e., MA, SA with engine-on and SA with engine-off. In the case study, fuel consumption and emissions of a single vehicle and a road network are estimated and visualized with GPS data. The estimation accuracy of the proposed approach is 88.6%. We also analyze the types of activities that produced fuel consumption on each road segment to explore the patterns and mechanisms of fuel consumption in the study area. The results not only show the effectiveness of the proposed approaches in estimating fuel consumption/emissions but also indicate their advantages for uncovering the relationships between fuel consumption and vehicles’ activities in road networks. PMID:29561813
Estimation of vehicular emissions using dynamic emission factors: A case study of Delhi, India
NASA Astrophysics Data System (ADS)
Mishra, Dhirendra; Goyal, P.
2014-12-01
The estimation of vehicular emissions depends mainly on the values of emission factors, which are used for the development of a comprehensive emission inventory of vehicles. In this study the variations of emission factors as well as the emission rates have been studied in Delhi. The implementation of compressed natural gas (CNG), in the diesel and petrol, public vehicles in the year 2001 has changed the complete air quality scenario of Delhi. The dynamic emission factors of criteria pollutants viz. carbon monoxide (CO), nitrogen oxide (NOx) and particulate matter (PM10) for all types of vehicles have been developed after, which are based on the several factors such as regulated emission limits, number of vehicle deterioration, vehicle increment, vehicle age etc. These emission factors are found to be decreased continuously throughout the study years 2003-2012. The International Vehicle Emissions (IVE) model is used to estimate the emissions of criteria pollutants by utilizing a dataset available from field observations at different traffic intersections in Delhi. Thus the vehicular emissions, based on dynamic emission factors have been estimated for the years 2003-2012, which are found to be comparable with the monitored concentrations at different locations in Delhi. It is noticed that the total emissions of CO, NOx, and PM10 are increased by 45.63%, 68.88% and 17.92%, respectively up to the year 2012 and the emissions of NOx and PM10 are grown continuously with an annual average growth rate of 5.4% and 1.7% respectively.
Split delivery vehicle routing problem with time windows: a case study
NASA Astrophysics Data System (ADS)
Latiffianti, E.; Siswanto, N.; Firmandani, R. A.
2018-04-01
This paper aims to implement an extension of VRP so called split delivery vehicle routing problem (SDVRP) with time windows in a case study involving pickups and deliveries of workers from several points of origin and several destinations. Each origin represents a bus stop and the destination represents either site or office location. An integer linear programming of the SDVRP problem is presented. The solution was generated using three stages of defining the starting points, assigning busses, and solving the SDVRP with time windows using an exact method. Although the overall computational time was relatively lengthy, the results indicated that the produced solution was better than the existing routing and scheduling that the firm used. The produced solution was also capable of reducing fuel cost by 9% that was obtained from shorter total distance travelled by the shuttle buses.
Optimization of ACC system spacing policy on curved highway
NASA Astrophysics Data System (ADS)
Ma, Jun; Qian, Kun; Gong, Zaiyan
2017-05-01
The paper optimizes the original spacing policy when adopting VTH (Variable Time Headway), proposes to introduce the road curve curvature K to the spacing policy to cope with following the wrong vehicle or failing to follow the vehicle owing to the radar limitation of curve in ACC system. By utilizing MATLAB/Simulink, automobile longitudinal dynamics model is established. At last, the paper sets up such three common cases as the vehicle ahead runs at a uniform velocity, an accelerated velocity and hits the brake suddenly, simulates these cases on the curve with different curvature, analyzes the curve spacing policy in the perspective of safety and vehicle following efficiency and draws the conclusion whether the optimization scheme is effective or not.
Side Impact Regulatory Trends, Crash Environment and Injury Risk in the USA.
Prasad, Priya; Dalmotas, Dainius; Chouinard, Aline
2015-11-01
Light duty vehicles in the US are designed to meet and exceed regulatory standards, self-imposed industry agreements and safety rating tests conducted by NHTSA and IIHS. The evolution of side impact regulation in the US from 1973 to 2015 is discussed in the paper along with two key industry agreements in 2003 affecting design of restraint systems and structures for side impact protection. A combination of all the above influences shows that vehicles in the US are being designed to more demanding and comprehensive requirements than in any other region of the world. The crash environment in the US related to side impacts was defined based on data in the nationally representative crash database NASS. Crash environment factors, including the distribution of cars, light trucks and vans (LTV's), and medium-to-heavy vehicles (MHV's) in the fleet, and the frequency of their interactions with one another in side impacts, were considered. Other factors like, crash severity in terms of closing velocity between two vehicles involved in crash, gender and age of involved drivers in two-vehicle and single vehicle crashes, were also examined. Injury risks in side impacts to drivers and passengers were determined in various circumstances such as near-side, far-side, and single vehicle crashes as a function of crash severity, in terms of estimated closing speed or lateral delta-V. Also injury risks in different pairs of striking and struck cars and LTV's, were estimated. A logistic regression model for studying injury risks in two vehicle crashes was developed. The risk factors included in the model include case and striking vehicles, consisting of cars, SUV's, vans, and pickup trucks, delta-V, damage extent, occupant proximity to the impact side, age and gender of the occupant, and belt use. Results show that car occupants make up the vast majority of serious-to-fatally injured occupants. Injury rates of car occupants in two-vehicle collision are highest when the car is struck by a pickup and lowest when struck by a car. This was the case across all lateral delta-V ranges. Additionally, near-side injury rates are substantially higher than those in far-side impacts.
Vision-Based Leader Vehicle Trajectory Tracking for Multiple Agricultural Vehicles
Zhang, Linhuan; Ahamed, Tofael; Zhang, Yan; Gao, Pengbo; Takigawa, Tomohiro
2016-01-01
The aim of this study was to design a navigation system composed of a human-controlled leader vehicle and a follower vehicle. The follower vehicle automatically tracks the leader vehicle. With such a system, a human driver can control two vehicles efficiently in agricultural operations. The tracking system was developed for the leader and the follower vehicle, and control of the follower was performed using a camera vision system. A stable and accurate monocular vision-based sensing system was designed, consisting of a camera and rectangular markers. Noise in the data acquisition was reduced by using the least-squares method. A feedback control algorithm was used to allow the follower vehicle to track the trajectory of the leader vehicle. A proportional–integral–derivative (PID) controller was introduced to maintain the required distance between the leader and the follower vehicle. Field experiments were conducted to evaluate the sensing and tracking performances of the leader-follower system while the leader vehicle was driven at an average speed of 0.3 m/s. In the case of linear trajectory tracking, the RMS errors were 6.5 cm, 8.9 cm and 16.4 cm for straight, turning and zigzag paths, respectively. Again, for parallel trajectory tracking, the root mean square (RMS) errors were found to be 7.1 cm, 14.6 cm and 14.0 cm for straight, turning and zigzag paths, respectively. The navigation performances indicated that the autonomous follower vehicle was able to follow the leader vehicle, and the tracking accuracy was found to be satisfactory. Therefore, the developed leader-follower system can be implemented for the harvesting of grains, using a combine as the leader and an unloader as the autonomous follower vehicle. PMID:27110793
Vision-Based Leader Vehicle Trajectory Tracking for Multiple Agricultural Vehicles.
Zhang, Linhuan; Ahamed, Tofael; Zhang, Yan; Gao, Pengbo; Takigawa, Tomohiro
2016-04-22
The aim of this study was to design a navigation system composed of a human-controlled leader vehicle and a follower vehicle. The follower vehicle automatically tracks the leader vehicle. With such a system, a human driver can control two vehicles efficiently in agricultural operations. The tracking system was developed for the leader and the follower vehicle, and control of the follower was performed using a camera vision system. A stable and accurate monocular vision-based sensing system was designed, consisting of a camera and rectangular markers. Noise in the data acquisition was reduced by using the least-squares method. A feedback control algorithm was used to allow the follower vehicle to track the trajectory of the leader vehicle. A proportional-integral-derivative (PID) controller was introduced to maintain the required distance between the leader and the follower vehicle. Field experiments were conducted to evaluate the sensing and tracking performances of the leader-follower system while the leader vehicle was driven at an average speed of 0.3 m/s. In the case of linear trajectory tracking, the RMS errors were 6.5 cm, 8.9 cm and 16.4 cm for straight, turning and zigzag paths, respectively. Again, for parallel trajectory tracking, the root mean square (RMS) errors were found to be 7.1 cm, 14.6 cm and 14.0 cm for straight, turning and zigzag paths, respectively. The navigation performances indicated that the autonomous follower vehicle was able to follow the leader vehicle, and the tracking accuracy was found to be satisfactory. Therefore, the developed leader-follower system can be implemented for the harvesting of grains, using a combine as the leader and an unloader as the autonomous follower vehicle.
[Dynamic road vehicle emission inventory simulation study based on real time traffic information].
Huang, Cheng; Liu, Juan; Chen, Chang-Hong; Zhang, Jian; Liu, Deng-Guo; Zhu, Jing-Yu; Huang, Wei-Ming; Chao, Yuan
2012-11-01
The vehicle activity survey, including traffic flow distribution, driving condition, and vehicle technologies, were conducted in Shanghai. The databases of vehicle flow, VSP distribution and vehicle categories were established according to the surveyed data. Based on this, a dynamic vehicle emission inventory simulation method was designed by using the real time traffic information data, such as traffic flow and average speed. Some roads in Shanghai city were selected to conduct the hourly vehicle emission simulation as a case study. The survey results show that light duty passenger car and taxi are major vehicles on the roads of Shanghai city, accounting for 48% - 72% and 15% - 43% of the total flow in each hour, respectively. VSP distribution has a good relationship with the average speed. The peak of VSP distribution tends to move to high load section and become lower with the increase of average speed. Vehicles achieved Euro 2 and Euro 3 standards are majorities of current vehicle population in Shanghai. Based on the calibration of vehicle travel mileage data, the proportions of Euro 2 and Euro 3 standard vehicles take up 11% - 70% and 17% - 51% in the real-world situation, respectively. The emission simulation results indicate that the ratios of emission peak and valley for the pollutants of CO, VOC, NO(x) and PM are 3.7, 4.6, 9.6 and 19.8, respectively. CO and VOC emissions mainly come from light-duty passenger car and taxi, which has a good relationship with the traffic flow. NO(x) and PM emissions are mainly from heavy-duty bus and public buses and mainly concentrate in the morning and evening peak hours. The established dynamic vehicle emission simulation method can reflect the change of actual road emission and output high emission road sectors and hours in real time. The method can provide an important technical means and decision-making basis for transportation environment management.
Pedestrian signalization and the risk of pedestrian-motor vehicle collisions in Lima, Peru
Quistberg, D. Alex; Koepsell, Thomas D.; Boyle, Linda Ng; Miranda, J. Jaime; Johnston, Brian D.; Ebel, Beth E.
2014-01-01
Safe walking environments are essential for protecting pedestrians and promoting physical activity. In Peru, pedestrians comprise of over three-quarters of road fatality victims. Pedestrian signalization plays an important role managing pedestrian and vehicle traffic and may help improve pedestrian safety. We examined the relationship between pedestrian-motor vehicle collisions and the presence of visible traffic signals, pedestrian signals, and signal timing to determine whether these countermeasures improved pedestrian safety. A matched case-control design was used where the units of study were crossing locations. We randomly sampled 97 control-matched collisions (weighted N=1134) at intersections occurring from October, 2010 to January, 2011 in Lima. Each case-control pair was matched on proximity, street classification, and number of lanes. Sites were visited between February, 2011 and September, 2011. Each analysis accounted for sampling weight and matching and was adjusted for vehicle and pedestrian traffic flow, crossing width, and mean vehicle speed. Collisions were more common where a phased pedestrian signal (green or red-lit signal) was present compared to no signalization (odds ratio [OR] 8.88, 95% Confidence Interval [CI] 1.32–59.6). A longer pedestrian-specific signal duration was associated with collision risk (OR 5.31, 95% CI 1.02–9.60 per 15-second interval). Collisions occurred more commonly in the presence of any signalization visible to pedestrians or pedestrian-specific signalization, though these associations were not statistically significant. Signalization efforts were not associated with lower risk for pedestrians; rather, they were associated with an increased risk of pedestrian-vehicle collisions. PMID:24821630
Pedestrian signalization and the risk of pedestrian-motor vehicle collisions in Lima, Peru.
Quistberg, D Alex; Koepsell, Thomas D; Boyle, Linda Ng; Miranda, J Jaime; Johnston, Brian D; Ebel, Beth E
2014-09-01
Safe walking environments are essential for protecting pedestrians and promoting physical activity. In Peru, pedestrians comprise over three-quarters of road fatality victims. Pedestrian signalization plays an important role managing pedestrian and vehicle traffic and may help improve pedestrian safety. We examined the relationship between pedestrian-motor vehicle collisions and the presence of visible traffic signals, pedestrian signals, and signal timing to determine whether these countermeasures improved pedestrian safety. A matched case-control design was used where the units of study were crossing locations. We randomly sampled 97 control-matched collisions (weighted N=1134) at intersections occurring from October, 2010 to January, 2011 in Lima. Each case-control pair was matched on proximity, street classification, and number of lanes. Sites were visited between February, 2011 and September, 2011. Each analysis accounted for sampling weight and matching and was adjusted for vehicle and pedestrian traffic flow, crossing width, and mean vehicle speed. Collisions were more common where a phased pedestrian signal (green or red-light signal) was present compared to no signalization (odds ratio [OR] 8.88, 95% Confidence Interval [CI] 1.32-59.6). A longer pedestrian-specific signal duration was associated with collision risk (OR 5.31, 95% CI 1.02-9.60 per 15-s interval). Collisions occurred more commonly in the presence of any signalization visible to pedestrians or pedestrian-specific signalization, though these associations were not statistically significant. Signalization efforts were not associated with lower risk for pedestrians; rather, they were associated with an increased risk of pedestrian-vehicle collisions. Copyright © 2014 Elsevier Ltd. All rights reserved.
19 CFR 158.27 - Accidental fire or other casualty.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Casualty, Loss, or Theft While in Customs Custody § 158.27 Accidental fire or other casualty. In the case... submitted: (a) A declaration of the master of the vessel, the conductor or driver of the vehicle, the... merchandise was on board the vessel or vehicle, in the warehouse, or otherwise in his charge, as the case may...
NASA Technical Reports Server (NTRS)
Nettles, A. T.; Hodge, A. J.; Jackson, J. R.
2010-01-01
The issue of fatigue loading of structures composed of composite materials is considered in a requirements document that is currently in place for manned launch vehicles. By taking into account the short life of these parts, coupled with design considerations, it is demonstrated that the necessary coupon level fatigue data collapse to a static case. Data from a literature review of past studies that examined compressive fatigue loading after impact and data generated from this experimental study are presented to support this finding. Damage growth, in the form of infrared thermography, was difficult to detect due to rapid degradation of compressive properties once damage growth initiated. Unrealistically high fatigue amplitudes were needed to fail 5 of 15 specimens before 10,000 cycles were reached. Since a typical vehicle structure, such as the Ares I interstage, only experiences a few cycles near limit load, it is concluded that static compression after impact (CAI) strength data will suffice for most launch vehicle structures.
A Study on the Influence of Speed on Road Roughness Sensing: The SmartRoadSense Case †
Alessandroni, Giacomo; Carini, Alberto; Lattanzi, Emanuele; Freschi, Valerio; Bogliolo, Alessandro
2017-01-01
SmartRoadSense is a crowdsensing project aimed at monitoring the conditions of the road surface. Using the sensors of a smartphone, SmartRoadSense monitors the vertical accelerations inside a vehicle traveling the road and extracts a roughness index conveying information about the road conditions. The roughness index and the smartphone GPS data are periodically sent to a central server where they are processed, associated with the specific road, and aggregated with data measured by other smartphones. This paper studies how the smartphone vertical accelerations and the roughness index are related to the vehicle speed. It is shown that the dependence can be locally approximated with a gamma (power) law. Extensive experimental results using data extracted from SmartRoadSense database confirm the gamma law relationship between the roughness index and the vehicle speed. The gamma law is then used for improving the SmartRoadSense data aggregation accounting for the effect of vehicle speed. PMID:28178224
Cost and Economics for Advanced Launch Vehicles
NASA Technical Reports Server (NTRS)
Whitfield, Jeff
1998-01-01
Market sensitivity and weight-based cost estimating relationships are key drivers in determining the financial viability of advanced space launch vehicle designs. Due to decreasing space transportation budgets and increasing foreign competition, it has become essential for financial assessments of prospective launch vehicles to be performed during the conceptual design phase. As part of this financial assessment, it is imperative to understand the relationship between market volatility, the uncertainty of weight estimates, and the economic viability of an advanced space launch vehicle program. This paper reports the results of a study that evaluated the economic risk inherent in market variability and the uncertainty of developing weight estimates for an advanced space launch vehicle program. The purpose of this study was to determine the sensitivity of a business case for advanced space flight design with respect to the changing nature of market conditions and the complexity of determining accurate weight estimations during the conceptual design phase. The expected uncertainty associated with these two factors drives the economic risk of the overall program. The study incorporates Monte Carlo simulation techniques to determine the probability of attaining specific levels of economic performance when the market and weight parameters are allowed to vary. This structured approach toward uncertainties allows for the assessment of risks associated with a launch vehicle program's economic performance. This results in the determination of the value of the additional risk placed on the project by these two factors.
Collision safety of a hard-shell low-mass vehicle
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaeser, R.; Walz, F.H.; Brunner, A.
1994-06-01
Low-mass vehicles and in particular low-mass electric vehicles as produced today in very small quantities are in general not designed for crashworthiness in collisions. Particular problems of compact low-mass cars are: reduced length of the car front, low mass compared to other vehicles, and heavy batteries in the case of an electric car. With the intention of studying design improvements, three frontal crash tests were run last year: the first one with a commercial, lightweight electric car; the second with a reinforced version of the same car; and the last one with a car based on a different structural designmore » with a `hard-shell` car body. Crash tests showed that the latter solution made better use of the small zone available for continuous energy absorption. The paper discusses further the problem of frontal collisions between vehicles of different weight and, in particular, the side collision. A side-collision test was run with the hard-shell vehicle following the ECE lateral-impact test procedure at 50 km/h and led to results for the EuroSIDI-dummy well below current injury tolerance criteria.« less
Collision safety of a hard-shell low-mass vehicle.
Kaeser, R; Walz, F H; Brunner, A
1994-06-01
Low-mass vehicles and in particular low-mass electric vehicles as produced today in very small quantities are in general not designed for crashworthiness in collisions. Particular problems of compact low-mass cars are: reduced length of the car front, low mass compared to other vehicles, and heavy batteries in the case of an electric car. With the intention of studying design improvements, three frontal crash tests were run last year: the first one with a commercial, lightweight electric car; the second with a reinforced version of the same car; and the last one with a car based on a different structural design with a "hard-shell" car body. Crash tests showed that the latter solution made better use of the small zone available for continuous energy absorption. The paper discusses further the problem of frontal collisions between vehicles of different weight and, in particular, the side collision. A side-collision test was run with the hard-shell vehicle following the ECE lateral-impact test procedure at 50 km/h and led to results for the EuroSID1-dummy well below current injury tolerance criteria.
Project EGRESS: The design of an assured crew return vehicle for the space station
NASA Technical Reports Server (NTRS)
1990-01-01
Keeping preliminary studies by NASA in mind, an Assured Crew Return Vehicle (ACRV) was developed. The system allows the escape of one or more crew members from Space Station Freedom in case of emergency. The design of the vehicle addresses propulsion, orbital operations, reentry, landing and recovery, power and communication, and life support. In light of recent modifications in Space Station design, Project EGRESS (Earthbound Guaranteed ReEntry from Space Station) pays particular attention to its impact on Space Station operations, interfaces and docking facilities, and maintenance needs. A water landing, medium lift vehicle was found to best satisfy project goals of simplicity and cost efficiency without sacrificing the safety and reliability requirements. With a single vehicle, one injured crew member could be returned to Earth with minimal pilot involvement. Since the craft is capable of returning up to five crew members, two such permanently docked vehicles would allow full evacuation of the Space Station. The craft could be constructed entirely with available 1990 technology and launched aboard a shuttle orbiter.
ERIC Educational Resources Information Center
Santiago, Maribel
2017-01-01
"Mendez v. Westminster," a case about 1940s Mexican American school segregation, is a new vehicle for including Mexican Americans into U.S. history classrooms. This study explores how a class of primarily Mexican American students, who because of their heritage might develop a personal connection to the case, made sense of…
Environmental Education Technologies in a Social Void: The Case of "Greendrive"
ERIC Educational Resources Information Center
Delicado, Ana
2012-01-01
This article is based on a case study that follows the trajectory of a technological device aimed at environmental education from the engineering laboratory in which it was designed into the contexts in which it is used. "Greendrive" is a driving simulator that accurately reproduces the performance of a vehicle in terms of fuel…
Code of Federal Regulations, 2013 CFR
2013-01-01
... contents of the label that you wish to use, and the reasons that you want to use it. (3) Electric vehicle... electric vehicle fuel dispensing systems. All type should be set in upper case (all caps) “Helvetica Black... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications...
Code of Federal Regulations, 2014 CFR
2014-01-01
... contents of the label that you wish to use, and the reasons that you want to use it. (3) Electric vehicle... electric vehicle fuel dispensing systems. All type should be set in upper case (all caps) “Helvetica Black... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications...
Code of Federal Regulations, 2012 CFR
2012-01-01
... contents of the label that you wish to use, and the reasons that you want to use it. (3) Electric vehicle... electric vehicle fuel dispensing systems. All type should be set in upper case (all caps) “Helvetica Black... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications...
40 CFR 1037.730 - ABT reports.
Code of Federal Regulations, 2014 CFR
2014-07-01
... identification number for the first vehicle covered by the new FEL. In this case, identify each applicable FEL... EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Averaging, Banking, and Trading for Certification § 1037.730 ABT reports. (a) If any of your vehicle families are certified using the ABT provisions of this...
77 FR 57191 - Proposed Collection; Comment Request for Notice 2006-54
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-17
... Notice 2006-54, Alternative Fuel Motor Vehicle Credit. DATES: Written comments should be received on or... INFORMATION: Title: Alternative Fuel Motor Vehicle Credit. OMB Number: 1545-1993. Notice Number: Notice 2006... motor vehicles to rely on the domestic manufacturer's (or, in the case of a foreign manufacturer, its...
Detection of foliage-obscured vehicle using a multiwavelength polarimetric lidar
Tan, S.; Stoker, J.; Greenlee, S.
2008-01-01
Foliage obscured man-made targets detection and identification is of great interest to many applications. In this paper, the backscattered laser signals from a multiwavelength polarimetric lidar were used to detect a vehicle hidden inside a vegetated area. The Polarimetric reflectance data from the lidar at two separate laser wavelengths at 1064 nm and 532 nm revealed distinct target characteristics from both the vehicle and the vegetation. The results from this case study demonstrated the validity of the proposed lidar detection technique. Furthermore, the results could potentially lead to a lidar detection and identification technique for a wide variety of foliage-obscured man-made targets under various application scenarios. ?? 2007 IEEE.
Driver Mortality in Paired Side Impact Collisions Due to Incompatible Vehicle Types
Crandall, C.S.
2003-01-01
Using a matched case control design, this study measured the mortality associated with paired passenger car-sport utility vehicle side impact (‘T-bone’) collisions using FARS data. Survival versus fatal outcome within the matched crash pairs was measured with matched pair odds ratios. Conditional logistic regression adjusted for multiple effects. Overall, passenger car drivers experienced greater mortality than did SUV drivers, regardless if they were in the struck or striking vehicle (odds ratio: 10.0; 95% confidence interval: 7.9, 12.5). Differential mortality persisted after adjustment for confounders. Efforts should be sought to improve passenger car side impact crashworthiness and to reduce SUV aggressivity. PMID:12941243
NASA Astrophysics Data System (ADS)
Bogatskaya, A. V.; Klenov, N. V.; Tereshonok, M. V.; Adjemov, S. S.; Popov, A. M.
2018-05-01
We present an analysis of the possibility of penetrating electromagnetic waves through opaque media using an optical-mechanical analogy. As an example, we consider the plasma sheath surrounding the vehicle as a potential barrier and analyze the overcoming of radiocommunication blackout problem. The idea is to embed a «resonator» between the surface on the vehicle and plasma sheath which is supposed to provide an effective tunneling of the signal to the receiving antenna. We discuss the peculiarities of optical mechanical analogy applicability and analyze the radio frequency wave tunneling regime in detail. The cases of normal and oblique incidence of radiofrequency waves on the vehicle surface are studied.
A multi-criteria decision aid methodology to design electric vehicles public charging networks
NASA Astrophysics Data System (ADS)
Raposo, João; Rodrigues, Ana; Silva, Carlos; Dentinho, Tomaz
2015-05-01
This article presents a new multi-criteria decision aid methodology, dynamic-PROMETHEE, here used to design electric vehicle charging networks. In applying this methodology to a Portuguese city, results suggest that it is effective in designing electric vehicle charging networks, generating time and policy based scenarios, considering offer and demand and the city's urban structure. Dynamic-PROMETHE adds to the already known PROMETHEE's characteristics other useful features, such as decision memory over time, versatility and adaptability. The case study, used here to present the dynamic-PROMETHEE, served as inspiration and base to create this new methodology. It can be used to model different problems and scenarios that may present similar requirement characteristics.
Intelligent behaviors through vehicle-to-vehicle and vehicle-to-infrastructure communication
NASA Astrophysics Data System (ADS)
Garcia, Richard D.; Sturgeon, Purser; Brown, Mike
2012-06-01
The last decade has seen a significant increase in intelligent safety devices on private automobiles. These devices have both increased and augmented the situational awareness of the driver and in some cases provided automated vehicle responses. To date almost all intelligent safety devices have relied on data directly perceived by the vehicle. This constraint has a direct impact on the types of solutions available to the vehicle. In an effort to improve the safety options available to a vehicle, numerous research laboratories and government agencies are investing time and resources into connecting vehicles to each other and to infrastructure-based devices. This work details several efforts in both the commercial vehicle and the private auto industries to increase vehicle safety and driver situational awareness through vehicle-to-vehicle and vehicle-to-infrastructure communication. It will specifically discuss intelligent behaviors being designed to automatically disable non-compliant vehicles, warn tractor trailer vehicles of unsafe lane maneuvers such as lane changes, passing, and merging, and alert drivers to non-line-of-sight emergencies.
NASA Astrophysics Data System (ADS)
Xu, Tongyi; Liang, Ming; Li, Chuan; Yang, Shuai
2015-10-01
A two-terminal mass (TTM) based vibration absorber with variable moment of inertia (VMI) for passive vehicle suspension is proposed. The VMI of the system is achieved by the motion of sliders embedded in a hydraulic driven flywheel. The moment of inertia increases in reaction to strong vertical vehicle oscillations and decreases for weak vertical oscillations. The hydraulic mechanism of the system converts the relative linear motion between the two terminals of the suspension into rotating motion of the flywheel. In the case of stronger vehicle vertical oscillation, the sliders inside the flywheel move away from the center of the flywheel because of the centrifugal force, hence yielding higher moment of inertia. The opposite is true in the case of weaker vehicle oscillation. As such, the moment of inertia adjusts itself adaptively in response to the road conditions. The performance of the proposed TTM-VMI absorber has been analyzed via dynamics modeling and simulation and further examined by experiments. In comparison to its counterpart with constant moment of inertia, the proposed VMI system offers faster response, better road handling and safety, improved ride comfort, and reduced suspension deflection except in the case of sinusoidal excitations.
NASA Technical Reports Server (NTRS)
Alexander, Reginald; Stanley, Thomas Troy
2001-01-01
Presented is a design tool and process that connects several disciplines which are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to all other systems, as is the case with SSTO vehicles with air breathing propulsion, which is currently being studied by the National Aeronautics and Space Administration (NASA). In particular, the thermal protection system (TPS) is linked directly to almost every major system. The propulsion system pushes the vehicle to velocities on the order of 15 times the speed of sound in the atmosphere before pulling up to go to orbit which results in high temperatures on the external surfaces of the vehicle. Thermal protection systems to maintain the structural integrity of the vehicle must be able to mitigate the heat transfer to the structure and be lightweight. Herein lies the interdependency, in that as the vehicle's speed increases, the TPS requirements are increased. And as TPS masses increase the effect on the propulsion system and all other systems is compounded. To adequately calculate the TPS mass of this type of vehicle several engineering disciplines and analytical tools must be used preferably in an environment that data is easily transferred and multiple iterations are easily facilitated.
A Case Study of the Failure on Apollo 13: Based on TMX-65270, Report of Apollo 13 Review Board
NASA Technical Reports Server (NTRS)
Anderson, Brenda Lindley
2011-01-01
The dramatic journey of the crippled Apollo 13 vehicle has been heavily documented and popularized. Many people know there was an explosion in the service module which caused the vehicle to lose its oxygen supply. Less well known is the set of circumstances which led to the explosion. This paper examines the manufacturing, processing and testing history of oxygen tank #2, detailing the additive effects which caused the oxygen to ignite and to overpressure the tank.
Estimate of Fuel Consumption and GHG Emission Impact from an Automated Mobility District
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yuche; Young, Stanley; Qi, Xuewei
2015-10-19
This study estimates the range of fuel and emissions impact of an automated-vehicle (AV) based transit system that services campus-based developments, termed an automated mobility district (AMD). The study develops a framework to quantify the fuel consumption and greenhouse gas (GHG) emission impacts of a transit system comprised of AVs, taking into consideration average vehicle fleet composition, fuel consumption/GHG emission of vehicles within specific speed bins, and the average occupancy of passenger vehicles and transit vehicles. The framework is exercised using a previous mobility analysis of a personal rapid transit (PRT) system, a system which shares many attributes with envisionedmore » AV-based transit systems. Total fuel consumption and GHG emissions with and without an AMD are estimated, providing a range of potential system impacts on sustainability. The results of a previous case study based of a proposed implementation of PRT on the Kansas State University (KSU) campus in Manhattan, Kansas, serves as the basis to estimate personal miles traveled supplanted by an AMD at varying levels of service. The results show that an AMD has the potential to reduce total system fuel consumption and GHG emissions, but the amount is largely dependent on operating and ridership assumptions. The study points to the need to better understand ride-sharing scenarios and calls for future research on sustainability benefits of an AMD system at both vehicle and system levels.« less
Implementation of probe data performance measures.
DOT National Transportation Integrated Search
2017-04-03
This report presents results from a 12-month project where three arterial analysis tools based on probe vehicle segment speed data were developed for District 6. A case study of 5 arterials and two incidents was performed.
Revised Standard Rules Tender Governing Motor Carrier Transportation
DOT National Transportation Integrated Search
2002-05-10
The following case study provides an in-depth view of the deployment of the safety information exchange components of the Commercial Vehicle Information Systems and Networks (CVISN) technology program in Connecticut. It describes successful practices...
NASA Astrophysics Data System (ADS)
Keiler, M.; Zischg, A.; Fuchs, S.; Hama, M.; Stötter, J.
2005-01-01
When determining risk related to natural hazard processes, many studies neglect the investigations of the damage potential or are limited to the assessment of immobile values like buildings. However, persons as well as mobile values form an essential part of the damage potential. Knowledge of the maximum number of exposed persons in an endangered area is of great importance for elaborating evacuation plans and immediate measures in case of catastrophes. In addition, motor vehicles can also be highly damaged, as was shown by the analysis of avalanche events. With the removal of mobile values in time as a preventive measure this kind of damage can be minimised. This study presents a method for recording the maximum number of exposed persons and monetarily assessing motor vehicles in the municipality of Galtür (Tyrol, Austria). Moreover, general developments of the damage potential due to significant socio-economic changes since the mid-twentieth century are pointed out in the study area. The present situation of the maximum number of persons and mobile values in the official avalanche hazard zones of the municipality is described in detail. Information on the number of persons is derived of census data, tourism and employment statistics. During the winter months, a significant increase overlaid by strong short-term fluctuation in the number of persons can be noted. These changes result from a higher demand of tourism related manpower as well as from varying occupancy rates. The number of motor vehicles in endangered areas is closely associated to the number of exposed persons. The potential number of motor vehicles is investigated by means of mapping, statistics on the stock of motor vehicles and the density distribution. Diurnal and seasonal fluctuations of the investigated damage potential are pointed out. The recording of the number of persons and mobile values in endangered areas is vital for any disaster management.
Optimal cooperative time-fixed impulsive rendezvous
NASA Technical Reports Server (NTRS)
Mirfakhraie, Koorosh; Conway, Bruce A.
1990-01-01
New capabilities have been added to a method that had been developed for determining optimal, i.e., minimum fuel, trajectories for the fixed-time cooperative rendezvous of two spacecraft. The method utilizes the primer vector theory. The new capabilities enable the method to accomodate cases in which there are fuel constraints on the spacecraft and/or enable the addition of a mid-course impulse to one of the vehicle's trajectories. Results are presented for a large number of cases, and the effect of varying parameters, such as vehicle fuel constraints, vehicle initial masses, and time allowed for the rendezvous, is demonstrated.
Kholod, N; Evans, M; Gusev, E; Yu, S; Malyshev, V; Tretyakova, S; Barinov, A
2016-03-15
This paper presents a methodology for calculating exhaust emissions from on-road transport in cities with low-quality traffic data and outdated vehicle registries. The methodology consists of data collection approaches and emission calculation methods. For data collection, the paper suggests using video survey and parking lot survey methods developed for the International Vehicular Emissions model. Additional sources of information include data from the largest transportation companies, vehicle inspection stations, and official vehicle registries. The paper suggests using the European Computer Programme to Calculate Emissions from Road Transport (COPERT) 4 model to calculate emissions, especially in countries that implemented European emissions standards. If available, the local emission factors should be used instead of the default COPERT emission factors. The paper also suggests additional steps in the methodology to calculate emissions only from diesel vehicles. We applied this methodology to calculate black carbon emissions from diesel on-road vehicles in Murmansk, Russia. The results from Murmansk show that diesel vehicles emitted 11.7 tons of black carbon in 2014. The main factors determining the level of emissions are the structure of the vehicle fleet and the level of vehicle emission controls. Vehicles without controls emit about 55% of black carbon emissions. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Koudelka, Petr; Hanulak, Patrik; Jaros, Jakub; Papes, Martin; Latal, Jan; Siska, Petr; Vasinek, Vladimir
2015-07-01
This paper discusses the implementation of a light emitting diode based visible light communication system for optical vehicle-to-vehicle (V2V) communications in road safety applications. The widespread use of LEDs as light sources has reached into automotive fields. For example, LEDs are used for taillights, daytime running lights, brake lights, headlights, and traffic signals. Future in the optical vehicle-to-vehicle (V2V) communications will be based on an optical wireless communication technology that using LED transmitter and a camera receiver (OCI; optical communication image sensor). Utilization of optical V2V communication systems in automotive industry naturally brings a lot of problems. Among them belongs necessity of circuit implementation into the current concepts of electronic LED lights control that allows LED modulation. These circuits are quite complicated especially in case of luxury cars. Other problem is correct design of modulation circuits so that final vehicle lightning using optical vehicle-to-vehicle (V2V) communication meets standard requirements on Photometric Quantities and Beam Homogeneity. Authors of this article performed research on optical vehicle-to-vehicle (V2V) communication possibilities of headlight (Jaguar) and taillight (Skoda) in terms of modulation circuits (M-PSK, M-QAM) implementation into the lamp concepts and final fulfilment of mandatory standards on Photometric Quantities and Beam Homogeneity.
NASA Astrophysics Data System (ADS)
Zhao, Z.-G.; Zhou, L.-J.; Zhang, J.-T.; Zhu, Q.; Hedrick, J.-K.
2017-05-01
Considering the controllability and observability of the braking torques of the hub motor, Integrated Starter Generator (ISG), and hydraulic brake for four-wheel drive (4WD) hybrid electric cars, a distributed and self-adaptive vehicle speed estimation algorithm for different braking situations has been proposed by fully utilising the Electronic Stability Program (ESP) sensor signals and multiple powersource signals. Firstly, the simulation platform of a 4WD hybrid electric car was established, which integrates an electronic-hydraulic composited braking system model and its control strategy, a nonlinear seven degrees-of-freedom vehicle dynamics model, and the Burckhardt tyre model. Secondly, combining the braking torque signals with the ESP signals, self-adaptive unscented Kalman sub-filter and main-filter adaptable to the observation noise were, respectively, designed. Thirdly, the fusion rules for the sub-filters and master filter were proposed herein, and the estimation results were compared with the simulated value of a real vehicle speed. Finally, based on the hardware in-the-loop platform and by picking up the regenerative motor torque signals and wheel cylinder pressure signals, the proposed speed estimation algorithm was tested under the case of moderate braking on the highly adhesive road, and the case of Antilock Braking System (ABS) action on the slippery road, as well as the case of ABS action on the icy road. Test results show that the presented vehicle speed estimation algorithm has not only a high precision but also a strong adaptability in the composite braking case.
On the required complexity of vehicle dynamic models for use in simulation-based highway design.
Brown, Alexander; Brennan, Sean
2014-06-01
This paper presents the results of a comprehensive project whose goal is to identify roadway design practices that maximize the margin of safety between the friction supply and friction demand. This study is motivated by the concern for increased accident rates on curves with steep downgrades, geometries that contain features that interact in all three dimensions - planar curves, grade, and superelevation. This complexity makes the prediction of vehicle skidding quite difficult, particularly for simple simulation models that have historically been used for road geometry design guidance. To obtain estimates of friction margin, this study considers a range of vehicle models, including: a point-mass model used by the American Association of State Highway Transportation Officials (AASHTO) design policy, a steady-state "bicycle model" formulation that considers only per-axle forces, a transient formulation of the bicycle model commonly used in vehicle stability control systems, and finally, a full multi-body simulation (CarSim and TruckSim) regularly used in the automotive industry for high-fidelity vehicle behavior prediction. The presence of skidding--the friction demand exceeding supply--was calculated for each model considering a wide range of vehicles and road situations. The results indicate that the most complicated vehicle models are generally unnecessary for predicting skidding events. However, there are specific maneuvers, namely braking events within lane changes and curves, which consistently predict the worst-case friction margins across all models. This suggests that any vehicle model used for roadway safety analysis should include the effects of combined cornering and braking. The point-mass model typically used by highway design professionals may not be appropriate to predict vehicle behavior on high-speed curves during braking in low-friction situations. However, engineers can use the results of this study to help select the appropriate vehicle dynamic model complexity to use in the highway design process. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Dawid, Rys; Piotr, Jaskula
2018-05-01
Oversized heavy duty vehicles occur in traffic very rarely but they reach extremely high weights, even up to 800 tonne. The detrimental impact of these vehicles on pavement structure is much higher than in case of commercial vehicles that comprise typical traffic, thus it is necessary to assess the sensitivity of pavement structure to passage of oversized vehicles. The paper presents results of sample calculations of load equivalency factor of a heavy duty oversized vehicle with usage of mechanistic-empirical approach. The effects of pavement thickness, type of distress (cracking or rutting) and pavement condition (new or old with structural damage) were considered in the paper. Analysis revealed that a single pass of an 800 tonne oversized vehicle is equivalent to pass of up to 377 standard 100 kN axles. Load equivalency factor calculated for thin structures is almost 3 times lower than for thick structures, however, the damage effect caused by one pass of an oversized vehicle is higher in the case of thin structure. Bearing capacity of a pavement structure may be qualified as sufficient for passage of an oversized heavy duty vehicle when the measured deflection, for example in an FWD test, does not exceed the maximum deflections derived from mechanistic-empirical analysis. The paper presents sample calculation of maximum deflections which allow to consider passage of an oversized vehicle as safe over different pavement structures. The paper provides road administration with a practical tool which helps to decide whether to issue a permit of passage for a given oversized vehicle.
Quantifying autonomous vehicles national fuel consumption impacts: A data-rich approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Yuche; Gonder, Jeffrey; Young, Stanley
Autonomous vehicles are drawing significant attention from governments, manufacturers and consumers. Experts predict them to be the primary means of transportation by the middle of this century. Recent literature shows that vehicle automation has the potential to alter traffic patterns, vehicle ownership, and land use, which may affect fuel consumption from the transportation sector. In this paper, we developed a data-rich analytical framework to quantify system-wide fuel impacts of automation in the United States by integrating (1) a dynamic vehicle sales, stock, and usage model, (2) an historical transportation network-level vehicle miles traveled (VMT)/vehicle activity database, and (3) estimates ofmore » automation's impacts on fuel efficiency and travel demand. The vehicle model considers dynamics in vehicle fleet turnover and fuel efficiency improvements of conventional and advanced vehicle fleet. The network activity database contains VMT, free-flow speeds, and historical speeds of road links that can help us accurately identify fuel-savings opportunities of automation. Based on the model setup and assumptions, we found that the impacts of automation on fuel consumption are quite wide-ranging - with the potential to reduce fuel consumption by 45% in our 'Optimistic' case or increase it by 30% in our 'Pessimistic' case. Second, implementing automation on urban roads could potentially result in larger fuel savings compared with highway automation because of the driving features of urban roads. Lastly, through scenario analysis, we showed that the proposed framework can be used for refined assessments as better data on vehicle-level fuel efficiency and travel demand impacts of automation become available.« less
Quantifying autonomous vehicles national fuel consumption impacts: A data-rich approach
Chen, Yuche; Gonder, Jeffrey; Young, Stanley; ...
2017-11-06
Autonomous vehicles are drawing significant attention from governments, manufacturers and consumers. Experts predict them to be the primary means of transportation by the middle of this century. Recent literature shows that vehicle automation has the potential to alter traffic patterns, vehicle ownership, and land use, which may affect fuel consumption from the transportation sector. In this paper, we developed a data-rich analytical framework to quantify system-wide fuel impacts of automation in the United States by integrating (1) a dynamic vehicle sales, stock, and usage model, (2) an historical transportation network-level vehicle miles traveled (VMT)/vehicle activity database, and (3) estimates ofmore » automation's impacts on fuel efficiency and travel demand. The vehicle model considers dynamics in vehicle fleet turnover and fuel efficiency improvements of conventional and advanced vehicle fleet. The network activity database contains VMT, free-flow speeds, and historical speeds of road links that can help us accurately identify fuel-savings opportunities of automation. Based on the model setup and assumptions, we found that the impacts of automation on fuel consumption are quite wide-ranging - with the potential to reduce fuel consumption by 45% in our 'Optimistic' case or increase it by 30% in our 'Pessimistic' case. Second, implementing automation on urban roads could potentially result in larger fuel savings compared with highway automation because of the driving features of urban roads. Lastly, through scenario analysis, we showed that the proposed framework can be used for refined assessments as better data on vehicle-level fuel efficiency and travel demand impacts of automation become available.« less
New methodology for fast prediction of wheel wear evolution
NASA Astrophysics Data System (ADS)
Apezetxea, I. S.; Perez, X.; Casanueva, C.; Alonso, A.
2017-07-01
In railway applications wear prediction in the wheel-rail interface is a fundamental matter in order to study problems such as wheel lifespan and the evolution of vehicle dynamic characteristic with time. However, one of the principal drawbacks of the existing methodologies for calculating the wear evolution is the computational cost. This paper proposes a new wear prediction methodology with a reduced computational cost. This methodology is based on two main steps: the first one is the substitution of the calculations over the whole network by the calculation of the contact conditions in certain characteristic point from whose result the wheel wear evolution can be inferred. The second one is the substitution of the dynamic calculation (time integration calculations) by the quasi-static calculation (the solution of the quasi-static situation of a vehicle at a certain point which is the same that neglecting the acceleration terms in the dynamic equations). These simplifications allow a significant reduction of computational cost to be obtained while maintaining an acceptable level of accuracy (error order of 5-10%). Several case studies are analysed along the paper with the objective of assessing the proposed methodology. The results obtained in the case studies allow concluding that the proposed methodology is valid for an arbitrary vehicle running through an arbitrary track layout.
Head injury causation scenarios for belted, rear-seated children in frontal impacts.
Bohman, Katarina; Arbogast, Kristy B; Bostrom, Ola
2011-02-01
Head injuries are the most common serious injuries sustained by children in motor vehicle crashes and are of critical importance with regard to long-term disability. There is a lack of understanding of how seat belt-restrained children sustain head injuries in frontal impacts. The aim of the study was to identify the AIS2+ head injury causation scenarios for rear-seated, belt-restrained children in frontal impacts, including the set of parameters contributing to the injury. In-depth crash investigations from two National Highway Traffic Safety Administration (NHTSA) databases, the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS; 1997-2008) and the Crash Injury Research and Engineering Network (CIREN; 1996-2009), were collected and analyzed in detail. Selection criteria were all frontal impacts with principal direction of force (PDOF) of 11, 12, and 1 o'clock involving rear-seated, three-point belt-restrained, with or without booster cushion, children from 3 to 13 years with an AIS2+ head injury. Cases were analyzed using the BioTab method of injury causation assessment in order to systematically analyze the injury causation scenario for each case. There were 27 cases meeting the inclusion criteria, 19 cases with MAIS2 head injuries and 8 cases with MAIS3+ head injuries, including 2 fatalities. Three major injury causation scenarios were identified, including head contact with seatback (10 cases), head contact with side interior (7 cases,) and no evidence of head contact (9 cases). Head injuries with seatback or side interior contact typically included a PDOF greater than 10 degree (similar to the Insurance Institute for Highway Safety [IIHS] and EuroNCAP offset frontal testing) and vehicle maneuvers. For seatback contact, the vehicle's movements contributed to occupant kinematics inboard the vehicle, causing a less than optimal restraint of the torso and/or torso roll out of the shoulder belt. For side interior contact, the PDOF and/or maneuvers forced the occupant toward the side interior. The cases without evidence of head/face contact were characterized by high crash severity and accompanied by severe injuries to the thorax and spine. These data lead to increased understanding of the injury patterns and causation in this crash restraint scenario so that interventions to mitigate the burden of injury can be advanced.
40 CFR 1051.730 - What ABT reports must I send to EPA?
Code of Federal Regulations, 2014 CFR
2014-07-01
..., identify the date that you started using the new FEL and/or give the vehicle identification number for the first vehicle covered by the new FEL. In this case, identify each applicable FEL and calculate the... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES AND VEHICLES Averaging, Banking, and...
40 CFR 1051.730 - What ABT reports must I send to EPA?
Code of Federal Regulations, 2011 CFR
2011-07-01
..., identify the date that you started using the new FEL and/or give the vehicle identification number for the first vehicle covered by the new FEL. In this case, identify each applicable FEL and calculate the... POLLUTION CONTROLS CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES AND VEHICLES Averaging, Banking, and...
49 CFR 393.26 - Requirements for reflectors.
Code of Federal Regulations, 2010 CFR
2010-10-01
... case of motor vehicles so constructed that requirement for a 381 mm (15-inch) minimum height above the... used in lieu of reflex reflectors if the material as used on the vehicle, meets the performance... motor vehicle. (3) Such surfaces shall be at least 3 inches from any required lamp or reflector unless...
75 FR 70775 - Submission for OMB Review; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-18
... approved collection. Title: Notice 2007-46--Credit for New Medium-Duty and Heavy-Duty Hybrid Motor Vehicles... hybrid vehicles to rely on the domestic manufacturer's (or, in the case of a foreign manufacturer, its... a qualified hybrid motor vehicle under Sec. 30B(3) and (d), and the amount of the credit allowable...
49 CFR 176.93 - Vehicles having refrigerating or heating equipment.
Code of Federal Regulations, 2013 CFR
2013-10-01
... combustion motors which expose the occupants of the passenger vehicles to excessive concentrations of exhaust fumes from such motors. (d) A transport vehicle containing solid carbon dioxide as a refrigerant may be... the motor stops it may not be restarted. (c) In the case of a ferry vessel on a voyage exceeding 30...
49 CFR 176.93 - Vehicles having refrigerating or heating equipment.
Code of Federal Regulations, 2014 CFR
2014-10-01
... combustion motors which expose the occupants of the passenger vehicles to excessive concentrations of exhaust fumes from such motors. (d) A transport vehicle containing solid carbon dioxide as a refrigerant may be... the motor stops it may not be restarted. (c) In the case of a ferry vessel on a voyage exceeding 30...
49 CFR 176.93 - Vehicles having refrigerating or heating equipment.
Code of Federal Regulations, 2012 CFR
2012-10-01
... combustion motors which expose the occupants of the passenger vehicles to excessive concentrations of exhaust fumes from such motors. (d) A transport vehicle containing solid carbon dioxide as a refrigerant may be... the motor stops it may not be restarted. (c) In the case of a ferry vessel on a voyage exceeding 30...
Lerner, E Brooke; Cushman, Jeremy T; Blatt, Alan; Lawrence, Richard D; Shah, Manish N; Swor, Robert A; Brasel, Karen; Jurkovich, Gregory J
2011-01-01
To determine the accuracy of emergency medical services (EMS) provider assessments of motor vehicle damage when compared with measurements made by a professional crash reconstructionist. EMS providers caring for adult patients injured during a motor vehicle crash and transported to the regional trauma center in a midsized community were interviewed upon emergency department arrival. The interview collected provider estimates of crash mechanism of injury. For crashes that met a preset severity threshold, the vehicle's owner was asked to consent to having a crash reconstructionist assess the vehicle. The assessment included measuring intrusion and external automobile deformity. Vehicle damage was used to calculate change in velocity. Paired t-test, correlation, and kappa were used to compare EMS estimates and investigator-derived values. Ninety-one vehicles were enrolled; of these, 58 were inspected and 33 were excluded because the vehicle was not accessible. Six vehicles had multiple patients. Therefore, a total of 68 EMS estimates were compared with the inspection findings. Patients were 46% male, 28% were admitted to hospital, and 1% died. The mean EMS-estimated deformity was 18 inches and the mean measured deformity was 14 inches. The mean EMS-estimated intrusion was 5 inches and the mean measured intrusion was 4 inches. The EMS providers and the reconstructionist had 68% agreement for determination of external automobile deformity (kappa 0.26) and 88% agreement for determination of intrusion (kappa 0.27) when the 1999 American College of Surgeons Field Triage Decision Scheme criteria were applied. The mean (± standard deviation) EMS-estimated speed prior to the crash was 48 ± 13 mph and the mean reconstructionist-estimated change in velocity was 18 ± 12 mph (correlation -0.45). The EMS providers determined that 19 vehicles had rolled over, whereas the investigator identified 18 (kappa 0.96). In 55 cases, EMS and the investigator agreed on seat belt use; for the remaining 13 cases, there was disagreement (five) or the investigator was unable to make a determination (eight) (kappa 0.40). This study found that EMS providers are good at estimating rollover. Vehicle intrusion, deformity, and seat belt use appear to be more difficult for EMS to estimate, with only fair agreement with the crash reconstructionist. As expected, the EMS provider -estimated speed prior to the crash does not appear to be a reasonable proxy for change in velocity.
How to use case studies: continuity cases vs. one-shot cases.
Reeves, P N
1992-01-01
Cases are a widely used instructional technique in health services administration education. This article discusses the merits of using cases in graduate education and identifies two types of cases, one-shot cases and continuity cases. The continuity case has many advantages for professional education. In particular it requires the students to recognize and cope with the interactions among decisions. Continuity cases are good vehicles both for instruction and for evaluation of students' competence. The supply of good continuity cases, however, is very limited. Consequently, despite the advantages of this type of case, instructors must consider using a blend of continuity and one-shot cases. Suggestions for the mix of cases within a curriculum are presented.
Detailed assessment of pedestrian ground contact injuries observed from in-depth accident data.
Shang, Shi; Otte, Dietmar; Li, Guibing; Simms, Ciaran
2018-01-01
Most pedestrians struck by vehicles receive injuries from contact with the vehicle and also from the subsequent ground contact. However, ground related pedestrian injuries have received little focus. This paper uses 1221 German pedestrian collision cases occurring between 2000 and 2015 to assess the distribution and risk factors for pedestrian ground related injuries. Results show that for MAIS 2, the ground accounted for 24% of cases, for MAIS 3 the ground accounted for 20% of cases and for MAIS 4-5, the ground accounted for 14% of cases. There were no AIS 6 ground related injuries, though there were several fatal cases where the ground was coded as the most serious injury. The head, thorax and spine dominate AIS 4-5 ground contact injuries. Vehicle impact speeds were higher for ground related AIS 4-5 compared to AIS 2 injury cases and the average impact speed for ground related injuries to the upper and lower extremities was lower than for body regions like head, thorax and spine. There was a significant age effect on pedestrian ground related injury outcome, with older pedestrians suffering more severe injuries and the median age for thorax injuries was higher than for all other body regions. There was no significant difference in the proportions of AIS 2+ head injuries produced by ground contact for more recent vehicles (model year since 2005) compared to older vehicles (model year before 2005). However, logistic regression analysis showed that the normalised bonnet leading-edge height is a risk factor for adult pedestrian AIS2+ ground related head injuries, and this provides empirical support for recent computational modelling predictions which implied a relationship between vehicle shape and pedestrian ground contact injuries. Considering the potential benefits of preventing pedestrian ground contact, for collisions below 40km/h two thirds of the injury costs would be eliminated if ground contact could be prevented, and even higher benefits are likely at lower speeds (20 and 30km/h). These data demonstrate the importance of ground related pedestrian injuries and show that vehicle shape influences pedestrian injury outcome in ground contact. The data therefore provides significant motivation for countermeasures to prevent or moderate pedestrian ground related injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.
Rieucau, G; Kiszka, J J; Castillo, J C; Mourier, J; Boswell, K M; Heithaus, M R
2018-06-01
A novel image analysis-based technique applied to unmanned aerial vehicle (UAV) survey data is described to detect and locate individual free-ranging sharks within aggregations. The method allows rapid collection of data and quantification of fine-scale swimming and collective patterns of sharks. We demonstrate the usefulness of this technique in a small-scale case study exploring the shoaling tendencies of blacktip reef sharks Carcharhinus melanopterus in a large lagoon within Moorea, French Polynesia. Using our approach, we found that C. melanopterus displayed increased alignment with shoal companions when distributed over a sandflat where they are regularly fed for ecotourism purposes as compared with when they shoaled in a deeper adjacent channel. Our case study highlights the potential of a relatively low-cost method that combines UAV survey data and image analysis to detect differences in shoaling patterns of free-ranging sharks in shallow habitats. This approach offers an alternative to current techniques commonly used in controlled settings that require time-consuming post-processing effort. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Does vehicle color influence the risk of being passively involved in a collision?
Lardelli-Claret, Pablo; De Dios Luna-Del-Castillo, Juan; Juan Jiménez-Moleón, José; Femia-Marzo, Pedro; Moreno-Abril, Obdulia; Bueno-Cavanillas, Aurora
2002-11-01
Bright- or light-colored vehicles are sometimes regarded as safer because they are presumably more visible. We examined the effect of vehicle color on the risk of being passively involved in a collision. This paired case-control study used data from the Spanish database of traffic crashes. We selected those collisions from 1993 to 1999 in which only one of the drivers committed an infraction. The violators constituted the control group; the other drivers formed the case group. Information about the color of the vehicle and other confounding variables was also collected. When white was compared with the remaining colors, a protective estimate was obtained (adjusted odds ratio [aOR] = 0.97; 95% confidence interval = 0.94-1.00). The results were similar for light colors (white plus yellow) compared with all remaining colors (aOR = 0.96; 0.94-0.99). The protective effect of light colors was specifically observed for open roads and under daylight conditions. It was stronger in conditions other than good weather (aOR = 0.91; 0.86-0.99) than in good weather conditions. Light colors (white and yellow) were associated with a slightly lower risk of being passively involved in a collision, although only under certain environmental conditions.
Yang, King H.
2015-01-01
Aortic injury (AI) leading to disruption of the aorta is an uncommon but highly lethal consequence of trauma in modern society. Most recent estimates range from 7,500 to 8,000 cases per year from a variety of causes. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest cavity. It is evident that effective means of substantially improving the outcome of motor vehicle crash-induced AIs is by preventing the injury in the first place. In the current study, 16 design of computer experiments (DOCE) were carried out with varying levels of principal direction of force (PDOF), impact velocity, impact height, and impact position of the bullet vehicle combined with occupant seating positions in the case vehicle to determine the effects of these factors on aortic injury. Further, a combination of real world crash data reported in the Crash Injury Research and Engineering Network (CIREN) database, Finite Element (FE) vehicle models, and the Wayne State Human Body Model-II (WSHBM-II) indicates that occupant seating position, impact height, and PDOF, in that order play, a primary role in aortic injury. PMID:26448781
An Architecture for Cooperative Localization in Underwater Acoustic Networks
2015-10-24
range. (b) Independent navigation and control system onboard Iver AUVs . The cooperative localization process is highlighted in red. Figure 1: Block...Iver2 AUVs (Fig. 3) and a topside ship. While we make spe- cific notes about this three vehicle network, the architecture is vehicle independent. 3.1...Single vehicle subsystem Each vehicle executes several processes including sensor drivers, a pose estimator (Section 2), and, in the case of the AUVs
AUV Commercialization - Who’s Leading the Pack?
2000-09-01
the Theseus and ARCS, is designing a deep water commercial site survey AUV for Fugro GeoServices Inc. Called the Explorer, the vehicle will conduct...ISE has the ARCS and the Theseus vehicles and Perry Technologies has the MUST. These vehicles have each performed some dramatic operations including the...deployment of fiber optic cables. In the case of Theseus , the fiber optic cable was deployed under the ice pack. Mid-size vehicles include those from
Crash fatality risk and unibody versus body-on-frame structure in SUVs.
Ossiander, Eric M; Koepsell, Thomas D; McKnight, Barbara
2014-09-01
In crashes between cars and SUVs, car occupants are more likely to be killed than if they crashed with another car. An increasing proportion of SUVs are built with unibody, rather than truck-like body-on-frame construction. Unibody SUVs are generally lighter, less stiff, and less likely to roll over than body-on-frame SUVs, but whether unibody structure affects risk of death in crashes is unknown. To determine whether unibody SUVs differ from body-on-frame SUVs in the danger they pose to occupants of other vehicles and in the self-protection they offer to their own occupants. Case-control study of crashes between one compact SUV and one other passenger vehicle in the US during 1995-2008, in which the SUV was model year 1996-2006. Cases were all decedents in fatal crashes, one control was selected from each non-fatal crash. Occupants of passenger vehicles that crashed with compact unibody SUVs were at 18% lower risk of death compared to those that crashed with compact body-on-frame SUVs (adjusted odds ratio 0.82 (95% confidence interval 0.73-0.94)). Occupants of compact unibody SUVs were also at lower risk of death compared to occupants of body-on-frame SUVs (0.86 (0.72-1.02)). In two-vehicle collisions involving compact SUVs, unibody structure was associated with lower risk of death both in occupants of other vehicles in the crash, and in SUVs' own occupants. Copyright © 2014 Elsevier Ltd. All rights reserved.
Recognizing medical emergencies
... persistent vomiting Sudden injury due to a motor vehicle accident, burns or smoke inhalation, near drowning, deep ... in case of a neck injury or motor vehicle accident) The person needs the skills or equipment ...
[Risk factors for road traffic injury in agricultural vehicle drivers].
Cui, M J; Chen, Y; Li, Y; Hu, J; Zhang, X J
2017-08-20
Objective: To examine the risk factors for road traffic injury in agricultural vehicle drivers. Methods: A total of 103 drivers (who had suffered agricultural vehicle road traffic injury within the past year based on the road traffic injury registrar from the Traffic Management Bureau) who were involved in the annual agricultural vehicle inspection from December 2014 to January 2015 were randomly sampled from the Yixing Agricultural Vehicle Station as the case group for this study. Based on a 1∶2 assignment ratio and matched for sex, age, and education, a total of 206 drivers who had not suffered any agricultural vehicle road traffic injury within the past year were selected as the control group. The general information, vehicle information, driving information, driving behavior, and accident details of the agricultural vehicle drivers were analyzed. Results: The incidence rate of road traffic injury was 7.24% given the 103 agricultural vehicle drivers who had suffered agricultural vehicle road traffic injury in the past year. Univariate logistic regression analysis showed that drinking, debt, pressure, history of car accident, history of drunk driving, smoking and phone use during driving, fatigue driving, and driving with illness were the risk factors for road traffic injury in agricultural vehicle drivers ( OR =2.332, 2.429, 19.778, 5.589, 8.517, 2.125, 3.203, 10.249 and 5.639, respectively) . Multivariate logistic regression analysis also demonstrated that pressure, history of car accident, history of drunk driving, fatigue driving, and driving with illness were the risk factors for road traffic injury in agricultural vehicle drivers ( OR =12.139, 11.184, 6.729, 5.939, and 6.544, respectively) . Conclusion: Pressure, history of car accident, history of drunk driving, fatigue driving, and driving with illness are the major risk factors for road traffic injury in agricultural vehicle drivers.
Orbit on demand - Will cost determine best design?
NASA Technical Reports Server (NTRS)
Macconochie, J. O.; Mackley, E. A.; Morris, S. J.; Phillips, W. P.; Breiner, C. A.; Scotti, S. J.
1985-01-01
Eleven design concepts for vertical (V) and horizontal (H) take-off launch-on-demand manned orbital vehicles are discussed. Attention is given to up to three stages, Mach numbers (sub-, 2, or 3), expendable boosters, drop tanks (DT), and storable (S) or cryogenic fuels. All the concepts feature lifting bodies with circular cross-section and most have a 7 ft diam, 15 ft long payload bay as well as a crew compartment. Expendable elements impose higher costs and in some cases reduce all-azimuth launch capabilities. Single-stage vehicles simplify the logistics whether in H or V configuration. A two-stage H vehicle offers launch offset for the desired orbital plane before firing the rocket engines after take-off and subsonic acceleration. A two-stage fully reusable V form has the second lowest weight of the vehicles studied and an all-azimuth launch capability. Better definition of the prospective mission requirements is needed before choosing among the alternatives.
Unmanned Aerial Vehicle Systems for Disaster Relief: Tornado Alley
NASA Technical Reports Server (NTRS)
DeBusk, Wesley M.
2009-01-01
Unmanned aerial vehicle systems are currently in limited use for public service missions worldwide. Development of civil unmanned technology in the United States currently lags behind military unmanned technology development in part because of unresolved regulatory and technological issues. Civil unmanned aerial vehicle systems have potential to augment disaster relief and emergency response efforts. Optimal design of aerial systems for such applications will lead to unmanned vehicles which provide maximum potentiality for relief and emergency response while accounting for public safety concerns and regulatory requirements. A case study is presented that demonstrates application of a civil unmanned system to a disaster relief mission with the intent on saving lives. The concept utilizes unmanned aircraft to obtain advanced warning and damage assessments for tornados and severe thunderstorms. Overview of a tornado watch mission architecture as well as commentary on risk, cost, need for, and design tradeoffs for unmanned aerial systems are provided.
Human Engineering of Space Vehicle Displays and Controls
NASA Technical Reports Server (NTRS)
Whitmore, Mihriban; Holden, Kritina L.; Boyer, Jennifer; Stephens, John-Paul; Ezer, Neta; Sandor, Aniko
2010-01-01
Proper attention to the integration of the human needs in the vehicle displays and controls design process creates a safe and productive environment for crew. Although this integration is critical for all phases of flight, for crew interfaces that are used during dynamic phases (e.g., ascent and entry), the integration is particularly important because of demanding environmental conditions. This panel addresses the process of how human engineering involvement ensures that human-system integration occurs early in the design and development process and continues throughout the lifecycle of a vehicle. This process includes the development of requirements and quantitative metrics to measure design success, research on fundamental design questions, human-in-the-loop evaluations, and iterative design. Processes and results from research on displays and controls; the creation and validation of usability, workload, and consistency metrics; and the design and evaluation of crew interfaces for NASA's Crew Exploration Vehicle are used as case studies.
Niu, Gang; Jiang, Junjie; Youn, Byeng D; Pecht, Michael
2018-01-01
Autonomous vehicles are playing an increasingly importance in support of a wide variety of critical events. This paper presents a novel autonomous health management scheme on rail vehicles driven by permanent magnet synchronous motors (PMSMs). Firstly, the PMSMs are modeled based on first principle to deduce the initial profile of pneumatic braking (p-braking) force, then which is utilized for real-time demagnetization monitoring and degradation prognosis through similarity-based theory and generate prognosis-enhanced p-braking force strategy for final optimal control. A case study is conducted to demonstrate the feasibility and benefit of using the real-time prognostics and health management (PHM) information in vehicle 'drive-brake' control automatically. The results show that accurate demagnetization monitoring, degradation prognosis, and real-time capability for control optimization can be obtained, which can effectively relieve brake shoe wear. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.
Jones, Derek A; Gaewsky, James P; Kelley, Mireille E; Weaver, Ashley A; Miller, Anna N; Stitzel, Joel D
2016-09-01
The objective of this study was to reconstruct 4 real-world motor vehicle crashes (MVCs), 2 with lumbar vertebral fractures and 2 without vertebral fractures in order to elucidate the MVC and/or restraint variables that increase this injury risk. A finite element (FE) simplified vehicle model (SVM) was used in conjunction with a previously developed semi-automated tuning method to arrive at 4 SVMs that were tuned to mimic frontal crash responses of a 2006 Chevrolet Cobalt, 2012 Ford Escape, 2007 Hummer H3, and 2002 Chevrolet Cavalier. Real-world crashes in the first 2 vehicles resulted in lumbar vertebrae fractures, whereas the latter 2 did not. Once each SVM was tuned to its corresponding vehicle, the Total HUman Model for Safety (THUMS) v4.01 was positioned in 120 precrash configurations in each SVM by varying 5 parameters using a Latin hypercube design (LHD) of experiments: seat track position, seatback angle, steering column angle, steering column telescoping position, and d-ring height. For each case, the event data recorder (EDR) crash pulse was used to apply kinematic boundary conditions to the model. By analyzing cross-sectional vertebral loads, vertebral bending moments, and maximum principal strain and stress in both cortical and trabecular bone, injury metric response as a function of posture and restraint parameters was computed. Tuning the SVM to specific vehicle models produced close matches between the simulated and experimental crash test responses for head, T6, and pelvis resultant acceleration; left and right femur loads; and shoulder and lap belt loads. Though vertebral load in the THUMS simulations was highly similar between injury cases and noninjury cases, the amount of bending moment was much higher for the injury cases. Seatback angle had a large effect on the maximum compressive load and bending moment in the lumbar spine, indicating the upward tilt of the seat pan in conjunction with precrash positioning may increase the likelihood of suffering lumbar injury even in frontal, planar MVCs. In conclusion, precrash positioning has a large effect on lumbar injury metrics. The lack of lumbar injury criteria in regulatory crash tests may have led to inadvertent design of seat pans that work to apply axial force to the spinal column during frontal crashes.
Preliminary plan for case-control crash risk study
DOT National Transportation Integrated Search
2002-01-31
The goal of the Federal Motor Carrier Safety Administration (FMCSA) is to reduce commercial vehicle-related fatalities and injuries. This is achieved through a thorough understanding of crash characteristics, precursors, and risk factors. This will h...
Transit evacuation planning : two case studies.
DOT National Transportation Integrated Search
2010-06-01
This project addresses the emergency transit evacuation of individuals without personal vehicles or the : means to acquire them during extreme coastal events. It is a joint effort of the University Transportation : Center for Alabama (UTCA) and the C...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clifford, M.J.; Wickstrom, G.V.
1983-10-01
Preferred treatment of high occupancy vehicles (HOV's), through strategies such as dedicated lanes, can achieve transportation energy conservation. The research presented in this report provides a method for regional planning agencies to assess such HOV facilities, from a travel demand and energy consumption standpoint. The planning process is described and applied in a case study. Products of the case study included estimates of carpool formation and associated fuel savings, and traffic operations on HOV and other facilities in the corridor. The completed process represents a method to examine HOV's under a variety of policy and operational conditions. The process ismore » within the modeling capabilities of other Metropolitan Planning Organizations (MPO's) and should be transferable to other cities and corridors. Additional applications of the HOV estimation and evaluation process are recommended.« less
Fixed-Wing Micro Aerial Vehicle for Accurate Corridor Mapping
NASA Astrophysics Data System (ADS)
Rehak, M.; Skaloud, J.
2015-08-01
In this study we present a Micro Aerial Vehicle (MAV) equipped with precise position and attitude sensors that together with a pre-calibrated camera enables accurate corridor mapping. The design of the platform is based on widely available model components to which we integrate an open-source autopilot, customized mass-market camera and navigation sensors. We adapt the concepts of system calibration from larger mapping platforms to MAV and evaluate them practically for their achievable accuracy. We present case studies for accurate mapping without ground control points: first for a block configuration, later for a narrow corridor. We evaluate the mapping accuracy with respect to checkpoints and digital terrain model. We show that while it is possible to achieve pixel (3-5 cm) mapping accuracy in both cases, precise aerial position control is sufficient for block configuration, the precise position and attitude control is required for corridor mapping.
Brown, Michael J.; Williams, Michael D.; Nelson, Matthew A.; Werley, Kenneth A.
2015-01-01
The Quick Urban and Industrial Complex (QUIC) plume modeling system is used to explore how the transport and dispersion of vehicle emissions in cities are impacted by the presence of buildings. Using downtown Philadelphia as a test case, notional vehicle emissions of gases and particles are specified as line source releases on a subset of the east–west and north–south streets. Cases were run in flat terrain and with 3D buildings present in order to show the differences in the model-computed outdoor concentration fields with and without buildings present. The QUIC calculations show that buildings result in regions with much higher concentrations and other areas with much lower concentrations when compared to the flat-earth case. On the roads with vehicle emissions, street-level concentrations were up to a factor of 10 higher when buildings were on either side of the street as compared to the flat-earth case due to trapping of pollutants between buildings. However, on roads without vehicle emissions and in other open areas, the concentrations were up to a factor of 100 times smaller as compared to the flat earth case because of vertical mixing of the vehicle emissions to building height in the cavity circulation that develops on the downwind side of unsheltered buildings. QUIC was also used to calculate infiltration of the contaminant into the buildings. Indoor concentration levels were found to be much lower than outdoor concentrations because of deposition onto indoor surfaces and particulate capture for buildings with filtration systems. Large differences in indoor concentrations from building to building resulted from differences in leakiness, air handling unit volume exchange rates, and filter type and for naturally ventilated buildings, whether or not the building was sheltered from the prevailing wind by a building immediately upwind. PMID:27867300
Selected Topics on Decision Making for Electric Vehicles
NASA Astrophysics Data System (ADS)
Sweda, Timothy Matthew
Electric vehicles (EVs) are an attractive alternative to conventional gasoline-powered vehicles due to their lower emissions, fuel costs, and maintenance costs. Range anxiety, or the fear of running out of charge prior to reaching one's destination, remains a significant concern, however. In this dissertation, we address the issue of range anxiety by developing a set of decision support tools for both charging infrastructure providers and EV drivers. In Chapter 1, we present an agent-based information system for identifying patterns in residential EV ownership and driving activities to enable strategic deployment of new charging infrastructure. Driver agents consider their own driving activities within the simulated environment, in addition to the presence of charging stations and the vehicle ownership of others in their social networks, when purchasing a new vehicle. The Chicagoland area is used as a case study to demonstrate the model, and several deployment scenarios are analyzed. In Chapter 2, we address the problem of finding an optimal recharging policy for an EV along a given path. The path consists of a sequence of nodes, each representing a charging station, and the driver must decide where to stop and how much to recharge at each stop. We present efficient algorithms for finding an optimal policy in general instances with deterministic travel costs and homogeneous charging stations, and also for two specialized cases. In addition, we develop two heuristic procedures that we characterize analytically and explore empirically. We further analyze and test our solution methods on model variations that include stochastic travel costs and nonhomogeneous charging stations. In Chapter 3, we study the problem of finding an optimal routing and recharging policy for an electric vehicle in a grid network. Each node in the network represents a charging station and has an associated probability of being available at any point in time or occupied by another vehicle. We present an efficient algorithm for finding an optimal a priori route and recharging policy as well as heuristic methods for finding adaptive policies. We conduct numerical experiments to demonstrate the empirical performance of our solutions.
Compatibility of booster seats and vehicles in the U.S. market.
Bing, Julie A; Agnew, Amanda M; Bolte, John H
2018-05-19
The objective of this study was to analyze booster and rear vehicle seat dimensions to identify the most frequent compatibility problems. Measurements were collected from 40 high-back and backless boosters and 95 left rear and center rear row seating positions in 50 modern vehicles. Dimensions were compared for 3,800 booster/vehicle seat combinations. For validation and estimation of tolerance and correction factors, 72 booster installations were physically completed and compared with measurement-based compatibility predictions. Dimensions were also compared to the International Organization for Standardization (ISO) volumetric envelopes of forward-facing child restraints and boosters. Seat belt buckles in outboard positions accommodated the width of boosters better than center positions (success rates of 85.4 and 34.7%, respectively). Adequate head restraint clearance occurred in 71.9 to 77.2% of combinations, depending on the booster's head support setting. Booster recline angles aligned properly with vehicle seat cushion angles in 71.5% of combinations. In cases of poor angle alignment, booster angles were more obtuse than the vehicle seat angles 97.7% of the time. Head restraint interference exacerbated angle alignment issues. Data indicate success rates above 90% for boosters being fully supported by the length of the seat cushion and for adequate height clearance with the vehicle roofline. Comparison to ISO envelopes indicates that most boosters on the U.S. market are taller and angled more obtusely than ISO target envelopes. This study quantifies some of the common interferences between boosters and vehicles that may complicate booster usage. Data are useful for design and to prioritize specific problem areas.
NASA Astrophysics Data System (ADS)
Kouroussis, G.; Verlinden, O.; Conti, C.
2012-04-01
A study is performed on the influence of some typical railway vehicle and track parameters on the level of ground vibrations induced in the neighbourhood. The results are obtained from a previously validated simulation framework considering in a first step the vehicle/track subsystem and, in a second step, the response of the soil to the forces resulting from the first analysis. The vehicle is reduced to a simple vertical 3-dof model, corresponding to the superposition of the wheelset, the bogie and the car body. The rail is modelled as a succession of beam elements elastically supported by the sleepers, lying themselves on a flexible foundation representing the ballast and the subgrade. The connection between the wheels and the rails is realised through a non-linear Hertzian contact. The soil motion is obtained from a finite/infinite element model. The investigated vehicle parameters are its type (urban, high speed, freight, etc.) and its speed. For the track, the rail flexural stiffness, the railpad stiffness, the spacing between sleepers and the rail and sleeper masses are considered. In all cases, the parameter value range is defined from a bibliographic browsing. At the end, the paper proposes a table summarising the influence of each studied parameter on three indicators: the vehicle acceleration, the rail velocity and the soil velocity. It namely turns out that the vehicle has a serious influence on the vibration level and should be considered in prediction models.
NASA Technical Reports Server (NTRS)
Gillette, W. B.; Turner, M. J.; Southall, J. W.; Whitener, P. C.; Kowalik, J. S.
1973-01-01
The extent to which IPAD is to support the design process is identified. Case studies of representative aerospace products were developed as models to characterize the design process and to provide design requirements for the IPAD computing system.
Optimal cooperative time-fixed impulsive rendezvous
NASA Technical Reports Server (NTRS)
Mirfakhraie, Koorosh; Conway, Bruce A.; Prussing, John E.
1988-01-01
A method has been developed for determining optimal, i.e., minimum fuel, trajectories for the fixed-time cooperative rendezvous of two spacecraft. The method presently assumes that the vehicles perform a total of three impulsive maneuvers with each vehicle being active, that is, making at least one maneuver. The cost of a feasible 'reference' trajectory is improved by an optimizer which uses an analytical gradient developed using primer vector theory and a new solution for the optimal terminal (rendezvous) maneuver. Results are presented for a large number of cases in which the initial orbits of both vehicles are circular but in which the initial positions of the vehicles and the allotted time for rendezvous are varied. In general, the cost of the cooperative rendezvous is less than that of rendezvous with one vehicle passive. Further improvement in cost may be obtained in the future when additional, i.e., midcourse, impulses are allowed and inserted as indicated for some cases by the primer vector histories which are generated by the program.
NASA Astrophysics Data System (ADS)
Zhang, Shaojun; Wu, Ye; Wu, Xiaomeng; Li, Mengliang; Ge, Yunshan; Liang, Bin; Xu, Yueyun; Zhou, Yu; Liu, Huan; Fu, Lixin; Hao, Jiming
2014-06-01
As a pioneer in controlling vehicle emissions within China, Beijing released the Clean Air Action Plan 2013-2017 document in August 2013 to improve its urban air quality. It has put forward this plan containing the most stringent emission control policies and strategies to be adopted for on-road vehicles of Beijing. This paper estimates the historic and future trends and uncertainties in vehicle emissions of Beijing from 1998 to 2020 by applying a new emission factor model for the Beijing vehicle fleet (EMBEV). Our updated results show that total emissions of CO, THC, NOx and PM2.5 from the Beijing vehicle fleet are 507 (395-819) kt, 59.1 (41.2-90.5) kt, 74.7 (54.9-103.9) kt and 2.69 (1.91-4.17) kt, respectively, at a 95% confidence level. This represents significant reductions of 58%, 59%, 31% and 62%, respectively, relative to the total vehicle emissions in 1998. The past trends clearly posed a challenge to NOx emission mitigation for the Beijing vehicle fleet, especially in light of those increasing NOx emissions from heavy-duty diesel vehicles (HDDVs) which have partly offset the reduction benefit from light-duty gasoline vehicles (LDGVs). Because of recently announced vehicle emission controls to be adopted in Beijing, including tighter emissions standards, limitations on vehicle growth by more stringent license control, promotion of alternative fuel technologies (e.g., natural gas) and the scrappage of older vehicles, estimated vehicle emissions in Beijing will continue to be mitigated by 74% of CO, 68% of THC, 56% of NOx and 72% of PM2.5 in 2020 compared to 2010 levels. Considering that many of the megacities in China are facing tremendous pressures to mitigate emissions from on-road vehicles, our assessment will provide a timely case study of significance for policy-makers in China.
Electromagnetic Launch Vehicle Fairing and Acoustic Blanket Model of Received Power Using FEKO
NASA Technical Reports Server (NTRS)
Trout, Dawn H.; Stanley, James E.; Wahid, Parveen F.
2011-01-01
Evaluating the impact of radio frequency transmission in vehicle fairings is important to electromagnetically sensitive spacecraft. This study employs the multilevel fast multipole method (MLFMM) from a commercial electromagnetic tool, FEKO, to model the fairing electromagnetic environment in the presence of an internal transmitter with improved accuracy over industry applied techniques. This fairing model includes material properties representative of acoustic blanketing commonly used in vehicles. Equivalent surface material models within FEKO were successfully applied to simulate the test case. Finally, a simplified model is presented using Nicholson Ross Weir derived blanket material properties. These properties are implemented with the coated metal option to reduce the model to one layer within the accuracy of the original three layer simulation.
2018-01-01
Advanced driver assistance systems, ADAS, have shown the possibility to anticipate crash accidents and effectively assist road users in critical traffic situations. This is not the case for motorcyclists, in fact ADAS for motorcycles are still barely developed. Our aim was to study a camera-based sensor for the application of preventive safety in tilting vehicles. We identified two road conflict situations for which automotive remote sensors installed in a tilting vehicle are likely to fail in the identification of critical obstacles. Accordingly, we set two experiments conducted in real traffic conditions to test our stereo vision sensor. Our promising results support the application of this type of sensors for advanced motorcycle safety applications. PMID:29351267
Samai, O; Sengeh, P
1997-11-01
Focus group discussions revealed poor roads, few vehicles, and high transportation costs as major causes of delay in deciding to seek and in reaching emergency obstetric care. Beginning in September 1992, a four-wheel drive vehicle was posted at Bo Government Hospital (BGH). Motorbikes to summon the vehicle were posted at the eight project-area primary health units (PHUs). Problems with the motorbike system (accidents, breakdowns) led to the installation of a radio system linking the hospital, PHUs and the referral vehicle. These interventions were complemented by community education activities and earlier improvements in the health facilities. The number of women with major obstetric complications arriving at BGH from the project area increased from 0.9 to 2.6 per month, while case fatality rate dropped from 20% to 10%. In the post-intervention period, approximately half of women with complications from the project area utilizing BGH came by project vehicle. The mean time from the vehicle being called by the PHU to the patient's arrival at BGH was 3.1 h. Case fatality rate did not differ by whether or not women came by project vehicle. Cost of the transport and communication intervention was approximately US $75,000, including: vehicle, $27,500; radios, $12,500; motorbikes, $27,000. Improvements in transport can help greater numbers of women with complications reach hospitals and may improve their chances of survival.
Minimum fuel coplanar aeroassisted orbital transfer using collocation and nonlinear programming
NASA Technical Reports Server (NTRS)
Shi, Yun Yuan; Young, D. H.
1991-01-01
The fuel optimal control problem arising in coplanar orbital transfer employing aeroassisted technology is addressed. The mission involves the transfer from high energy orbit (HEO) to low energy orbit (LEO) without plane change. The basic approach here is to employ a combination of propulsive maneuvers in space and aerodynamic maneuvers in the atmosphere. The basic sequence of events for the coplanar aeroassisted HEO to LEO orbit transfer consists of three phases. In the first phase, the transfer begins with a deorbit impulse at HEO which injects the vehicle into a elliptic transfer orbit with perigee inside the atmosphere. In the second phase, the vehicle is optimally controlled by lift and drag modulation to satisfy heating constraints and to exit the atmosphere with the desired flight path angle and velocity so that the apogee of the exit orbit is the altitude of the desired LEO. Finally, the second impulse is required to circularize the orbit at LEO. The performance index is maximum final mass. Simulation results show that the coplanar aerocapture is quite different from the case where orbital plane changes are made inside the atmosphere. In the latter case, the vehicle has to penetrate deeper into the atmosphere to perform the desired orbital plane change. For the coplanar case, the vehicle needs only to penetrate the atmosphere deep enough to reduce the exit velocity so the vehicle can be captured at the desired LEO. The peak heating rates are lower and the entry corridor is wider. From the thermal protection point of view, the coplanar transfer may be desirable. Parametric studies also show the maximum peak heating rates and the entry corridor width are functions of maximum lift coefficient. The problem is solved using a direct optimization technique which uses piecewise polynomial representation for the states and controls and collocation to represent the differential equations. This converts the optimal control problem into a nonlinear programming problem which is solved numerically by using a modified version of NPSOL. Solutions were obtained for the described problem for cases with and without heating constraints. The method appears to be more robust than other optimization methods. In addition, the method can handle complex dynamical constraints.
NASA Astrophysics Data System (ADS)
Michelberger, Frank; Wagner, Adrian; Ostermann, Michael; Maly, Thomas
2017-09-01
At railway lines with ballasted tracks, under unfavourable conditions, the so-called flying ballast can occur predominantly for trains driving at high speeds. Especially in wintertime, it is highly likely that the causes are adhered snow or ice deposits, which are falling off the vehicle. Due to the high kinetic energy, the impact can lead to the removal of ballast stones from the structure of the ballasted track. If the stones reach the height of vehicles underside, they may be accelerated significantly due to the collision with the vehicle or may detach further ice blocks. In the worst case, a reinforcing effect occurs, which can lead to considerable damage to railway vehicles (under-floor-area, vehicle exteriors, etc.) and infrastructure (signal masts, noise barriers, etc.). Additionally the flying gravel is a significant danger to people in the nearby area of the tracks. With this feasibility study the applicability and meaningfulness of an intelligent monitoring system for identification of the critical ice accumulation to prevent the ballast fly induced by ice dropping was examined. The key findings of the research are that the detection of ice on railway vehicles and the development of an intelligent monitoring seem to be possible with existing technologies, but a proof of concept in terms of field tests is necessary.
Methanol infrastructure — will it affect the introduction of SPFC vehicles?
NASA Astrophysics Data System (ADS)
Hart, D.; Leach, M. A.; Fouquet, R.; Pearson, P. J.; Bauen, A.
The possibility that future solid polymer fuel cell vehicles will be fuelled by methanol has been suggested. If this is the case, it will have significant implications for the future structure of the methanol supply industry, and methanol supply and availability may have an impact on the take-up of these SPFC vehicles. In this study, a model assessing the possible future penetration of methanol SPFC vehicles was constructed. This suggested that it would be possible for SPFC vehicles to achieve rapid market penetration after an initially slow start. A further model indicated that methanol supply would be adequate for vehicle demand until about 2013, when significant new capacity would be required. The cost of this new capacity was estimated, along with the cost of providing refuelling infrastructure such as road tankers, storage, and suitable fuelling stations. Amortising the cost over a short period (to 2013) could double the pre-tax price of methanol as a fuel, while over a longer timeframe (to 2029) it would add less than 10% to this value. The model suggests that methanol capacity need not be a constraint to the future introduction of SPFC vehicles using it as a fuel, but that other factors such as fuel purity and safety must be carefully considered before real costs can be calculated.
Schifter, I; Díaz, L; López-Salinas, E
2006-03-01
Light duty gasoline vehicles account for most of CO hydrocarbons and NOx emissions at the Metropolitan Area of Mexico City (MAMC). In order to ameliorate air pollution from the beginning of 2001, Tier 1 emission standards became mandatory for all new model year sold in the country. Car manufacturers in Mexico do not guarantee the performance of their exhaust emissions systems for a given mileage. The purpose of this study was to assess whether the Tier 1 vehicles will stand the certification values for at least 162000 km with the regular fuel available at the MAMC. Mileage accumulation and deterioration show that certified carbon monoxide emissions will stand for the useful life of the vehicles but in the case of non-methane hydrocarbons will be shorter by 40%, and nitrogen oxides emissions above the standard will be reached at one third of the accumulated kilometers. The effect of gasoline sulfur content, on the current in use Tier 1 vehicles of the MAMC and the impact on the emissions inventory in year 2010 showed that 31000 extra tons of NOx could be added to the inventory caused by the failure of the vehicles to control this pollutant at the useful life of vehicles.
Multi-modal vehicle display design and analysis
DOT National Transportation Integrated Search
2004-10-01
There is increasing interest in systematically studying the risks encountered while driving. In some cases, the : focus is on potential risks such as those associated with the use of in-car devices (e.g., mobile phones, radio, navigational : displays...
40 CFR 86.1110-87 - Sample selection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Penalties for Gasoline-Fueled and Diesel Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty... mass production processes for engines or vehicles to be distributed into commerce. In the case of heavy...
CVISN business case (commercial vehicle information systems and networks)
DOT National Transportation Integrated Search
2007-10-15
The objective was to evaluate economic justifications and institutional issues affecting motor carriers and State transportation agencies regarding the deployment of CVISN technologies. CVISN (Commercial Vehicle Information Systems and Networks) incl...
40 CFR 86.428-80 - Maintenance, scheduled; test vehicles.
Code of Federal Regulations, 2011 CFR
2011-07-01
... necessary. For example, piston and cylinder replacement caused by piston seizure which results in the vehicle being inoperative; or in the case of two-stroke engines, decarbonization, the need for which is...
40 CFR 86.428-80 - Maintenance, scheduled; test vehicles.
Code of Federal Regulations, 2012 CFR
2012-07-01
... necessary. For example, piston and cylinder replacement caused by piston seizure which results in the vehicle being inoperative; or in the case of two-stroke engines, decarbonization, the need for which is...
40 CFR 86.428-80 - Maintenance, scheduled; test vehicles.
Code of Federal Regulations, 2010 CFR
2010-07-01
... necessary. For example, piston and cylinder replacement caused by piston seizure which results in the vehicle being inoperative; or in the case of two-stroke engines, decarbonization, the need for which is...
40 CFR 86.428-80 - Maintenance, scheduled; test vehicles.
Code of Federal Regulations, 2014 CFR
2014-07-01
... necessary. For example, piston and cylinder replacement caused by piston seizure which results in the vehicle being inoperative; or in the case of two-stroke engines, decarbonization, the need for which is...
Karr, Jeffrey C
2017-11-01
A percutaneous antibiotic delivery technique (PAD-T) used for the adjunctive management of osteomyelitis is presented. This surgical technique incorporates a calcium sulfate and hydroxyapatite (calcium phosphate) bone void filler acting as a carrier vehicle with either an antibiotic or an antifungal medicine, delivering this combination directly into the area of osteomyelitis. The benefit of the PAD-T is reviewed with a case presentation of a successfully treated calcaneal osteomyelitis. No previously reported PAD-T using a simple bone cortex incision in the adjunctive treatment of osteomyelitis has been reported. The PAD-T safely and effectively uses a calcium sulfate and hydroxyapatite bone void filler carrier vehicle to deliver either an antibiotic or an antifungal medicine directly into the area of osteomyelitis.
Space vehicle acoustics prediction improvement for payloads. [space shuttle
NASA Technical Reports Server (NTRS)
Dandridge, R. E.
1979-01-01
The modal analysis method was extensively modified for the prediction of space vehicle noise reduction in the shuttle payload enclosure, and this program was adapted to the IBM 360 computer. The predicted noise reduction levels for two test cases were compared with experimental results to determine the validity of the analytical model for predicting space vehicle payload noise environments in the 10 Hz one-third octave band regime. The prediction approach for the two test cases generally gave reasonable magnitudes and trends when compared with the measured noise reduction spectra. The discrepancies in the predictions could be corrected primarily by improved modeling of the vehicle structural walls and of the enclosed acoustic space to obtain a more accurate assessment of normal modes. Techniques for improving and expandng the noise prediction for a payload environment are also suggested.
Coordination of networked systems on digraphs with multiple leaders via pinning control
NASA Astrophysics Data System (ADS)
Chen, Gang; Lewis, Frank L.
2012-02-01
It is well known that achieving consensus among a group of multi-vehicle systems by local distributed control is feasible if and only if all nodes in the communication digraph are reachable from a single (root) node. In this article, we take into account a more general case that the communication digraph of the networked multi-vehicle systems is weakly connected and has two or more zero-in-degree and strongly connected subgraphs, i.e. there are two or more leader groups. Based on the pinning control strategy, the feasibility problem of achieving second-order controlled consensus is studied. At first, a necessary and sufficient condition is given when the topology is fixed. Then the method to design the controller and the rule to choose the pinned vehicles are discussed. The proposed approach allows us to extend several existing results for undirected graphs to directed balanced graphs. A sufficient condition is proposed in the case where the coupling topology is variable. As an illustrative example, a second-order controlled consensus scheme is applied to coordinate the movement of networked multiple mobile robots.
Four linked outbreaks of Salmonella enteritidis phage type 4 infection--the continuing egg threat.
Ejidokun, O O; Killalea, D; Cooper, M; Holmyard, S; Cross, A; Kemp, C
2000-06-01
Four outbreaks of Salmonella enteritidis phage type (PT) 4 occurred among guests at functions for which a single commercial caterer supplied food. Retrospective cohort studies were used to describe the epidemiology of three of these outbreaks and identify the vehicle(s) responsible. Of 172 guests at these three events, 47 fitted the clinical case definition for illness and 24 cases were confirmed to have S. enteritidis PT4 infection. Food containing raw egg was identified epidemiologically as the likely vehicle of infection in two of the three outbreaks (odds ratios (OR) and 95% confidence intervals 9.1 (2.2-39.9) and 6.9 (1.2-46.4)). Logistic regression analysis yielded OR = 10.7 (p = 0.0022) and OR = 9.3 (p = 0.015) for egg consumption in two of the outbreaks. These outbreaks highlighted the continuing need to remind the public and commercial caterers of the potential high risks of contracting salmonella from shell eggs. Education of caterers includes advice to obtain eggs and other products from reputable and identifiable suppliers.
Prospective time-resolved LCA of fully electric supercap vehicles in Germany.
Zimmermann, Benedikt M; Dura, Hanna; Baumann, Manuel J; Weil, Marcel R
2015-07-01
The ongoing transition of the German electricity supply toward a higher share of renewable and sustainable energy sources, called Energiewende in German, has led to dynamic changes in the environmental impact of electricity over the last few years. Prominent scenario studies predict that comparable dynamics will continue in the coming decades, which will further improve the environmental performance of Germany's electricity supply. Life cycle assessment (LCA) is the methodology commonly used to evaluate environmental performance. Previous LCA studies on electric vehicles have shown that the electricity supply for the vehicles' operation is responsible for the major part of their environmental impact. The core question of this study is how the prospective dynamic development of the German electricity mix will affect the impact of electric vehicles operated in Germany and how LCA can be adapted to analyze this impact in a more robust manner. The previously suggested approach of time-resolved LCA, which is located between static and dynamic LCA, is used in this study and compared with several static approaches. Furthermore, the uncertainty issue associated with scenario studies is addressed in general and in relation to time-resolved LCA. Two scenario studies relevant to policy making have been selected, but a moderate number of modifications have been necessary to adapt the data to the requirements of a life cycle inventory. A potential, fully electric vehicle powered by a supercapacitor energy storage system is used as a generic example. The results show that substantial improvements in the environmental repercussions of the electricity supply and, consequentially, of electric vehicles will be achieved between 2020 and 2031 on the basis of the energy mixes predicted in both studies. This study concludes that although scenarios might not be able to predict the future, they should nonetheless be used as data sources in prospective LCA studies, because in many cases historic data appears to be unsuitable for providing realistic information on the future. The time-resolved LCA approach improves the assessment's robustness substantially, especially when nonlinear developments are foreseen in the future scenarios. This allows for a reduction of bias in LCA-based decision making. However, a deeper integration of time-resolved data in the life cycle inventory and the implementation of a more suitable software framework are desirable. The study describes how life cycle assessment's (LCA) robustness can be improved by respecting prospective fluctuations, like the transition of the German electricity mix, in the modeling of the life cycle inventory. It presents a feasible and rather simple process to add time-resolved data to LCA. The study selects 2 different future scenarios from important German studies and processes their data systematically to make them compatible with the requirements of a life cycle inventory. The use of external scenarios as basis for future-oriented LCA is reflected critically. A case study on electric mobility is presented and used to compare historic, prospective static, and prospective time-resolved electricity mix modeling approaches. The case study emphasizes the benefits of time-resolved LCA in direct comparison with the currently used approaches. © 2015 SETAC.
NASA Astrophysics Data System (ADS)
Yazdanie, Mashael; Noembrini, Fabrizio; Dossetto, Lionel; Boulouchos, Konstantinos
2014-03-01
This study provides a comprehensive analysis of well-to-wheel (WTW) primary energy demand and greenhouse gas (GHG) emissions for the operation of conventional and alternative passenger vehicle drivetrains. Results are determined based on a reference vehicle, drivetrain/production process efficiencies, and lifecycle inventory data specific to Switzerland. WTW performance is compared to a gasoline internal combustion engine vehicle (ICEV). Both industrialized and novel hydrogen and electricity production pathways are evaluated. A strong case is presented for pluggable electric vehicles (PEVs) due to their high drivetrain efficiency. However, WTW performance strongly depends on the electricity source. A critical electricity mix can be identified which divides optimal drivetrain performance between the EV, ICEV, and plug-in hybrid vehicle. Alternative drivetrain and energy carrier production pathways are also compared by natural resource. Fuel cell vehicle (FCV) performance proves to be on par with PEVs for energy carrier (EC) production via biomass and natural gas resources. However, PEVs outperform FCVs via solar energy EC production pathways. ICE drivetrains using alternative fuels, particularly biogas and CNG, yield remarkable WTW energy and emission reductions as well, indicating that alternative fuels, and not only alternative drivetrains, play an important role in the transition towards low-emission vehicles in Switzerland.
González, Domingo; Romero, Luis; Espinosa, María Del Mar; Domínguez, Manuel
2017-01-01
The aim of this paper is to present an optimization proposal in the automated guided vehicles design used in hospital logistics, as well as to analyze the impact of its implementation in a real environment. This proposal is based on the design of those elements that would allow the vehicles to deliver an extra cart by the towing method. So, the proposal intention is to improve the productivity and the performance of the current vehicles by using a transportation method of combined carts. The study has been developed following concurrent engineering premises from three different viewpoints. First, the sequence of operations has been described, and second, a proposal of design of the equipment has been undertaken. Finally, the impact of the proposal has been analyzed according to real data from the Hospital Universitario Rio Hortega in Valladolid (Spain). In this particular case, by the implementation of the analyzed proposal in the hospital a reduction of over 35% of the current time of use can be achieved. This result may allow adding new tasks to the vehicles, and according to this, both a new kind of vehicle and a specific module can be developed in order to get a better performance.
EMS Provider Assessment of Vehicle Damage Compared to a Professional Crash Reconstructionist
Lerner, E. Brooke; Cushman, Jeremy T.; Blatt, Alan; Lawrence, Richard; Shah, Manish N.; Swor, Robert; Brasel, Karen; Jurkovich, Gregory J.
2011-01-01
Objective To determine the accuracy of EMS provider assessments of motor vehicle damage, when compared to measurements made by a professional crash reconstructionist. Methods EMS providers caring for adult patients injured during a motor vehicle crash and transported to the regional trauma center in a midsized community were interviewed upon ED arrival. The interview collected provider estimates of crash mechanism of injury. For crashes that met a preset severity threshold, the vehicle’s owner was asked to consent to having a crash reconstructionist assess their vehicle. The assessment included measuring intrusion and external auto deformity. Vehicle damage was used to calculate change in velocity. Paired t-test and correlation were used to compare EMS estimates and investigator derived values. Results 91 vehicles were enrolled; of these 58 were inspected and 33 were excluded because the vehicle was not accessible. 6 vehicles had multiple patients. Therefore, a total of 68 EMS estimates were compared to the inspection findings. Patients were 46% male, 28% admitted to hospital, and 1% died. Mean EMS estimated deformity was 18” and mean measured was 14”. Mean EMS estimated intrusion was 5” and mean measured was 4”. EMS providers and the reconstructionist had 67% agreement for determination of external auto deformity (kappa 0.26), and 88% agreement for determination of intrusion (kappa 0.27) when the 1999 Field Triage Decision Scheme Criteria were applied. Mean EMS estimated speed prior to the crash was 48 mph±13 and mean reconstructionist estimated change in velocity was 18 mph±12 (correlation -0.45). EMS determined that 19 vehicles had rolled over while the investigator identified 18 (kappa 0.96). In 55 cases EMS and the investigator agreed on seatbelt use, for the remaining 13 cases there was disagreement (5) or the investigator was unable to make a determination (8) (kappa 0.40). Conclusions This study found that EMS providers are good at estimating rollover. Vehicle intrusion, deformity, and seatbelt use appear to be more difficult to estimate with only fair agreement with the crash reconstructionist. As expected, the EMS provider estimated speed prior to the crash does not appear to be a reasonable proxy for change in velocity. PMID:21815732
Greenop, Kathryn R; Hinwood, Andrea L; Fritschi, Lin; Scott, Rodney J; Attia, John; Ashton, Lesley J; Heath, John A; Armstrong, Bruce K; Milne, Elizabeth
2015-02-01
The aetiology of childhood brain tumours (CBT) is largely unknown. Damage to germ cells after parental exposure to airborne carcinogens, such as volatile organic compounds and polycyclic aromatic hydrocarbons is one plausible pathway. This analysis aimed to investigate whether parental refuelling of vehicles or the use of domestic wood heaters in key time periods relating to the child's birth was associated with an increased risk of CBT. Cases <15 years of age were recruited through 10 paediatric oncology centres around Australia; controls were recruited through nationwide random-digit dialling, frequency matched to cases on age, sex and State of residence. Exposure to refuelling and wood heaters was ascertained through questionnaires from both parents. Odds ratios (ORs) and confidence intervals (CIs) were estimated using unconditional logistic regression, adjusting for relevant covariates. Data were available for 306 case and 950 control families. Paternal refuelling ≥4 times/month was associated with an increased risk of CBT (OR 1.59, 95% CI: 1.11, 2.29), and a dose-dependent trend was observed (P = 0.004). No association was seen for maternal refuelling. Use of closed, but not open, wood heaters before (OR 1.51, 95% CI: 1.05, 2.15) and after (OR 1.44, 95% CI: 1.03, 2.01) the child's birth was associated with increased risk of CBT, but dose-response relationships were weak or absent. Paternal refuelling of vehicles ≥4 times/month and the use of closed wood heaters before the child's birth may increase the risk of CBT. Replication in larger studies is needed. Pediatr Blood Cancer 2015;62:229-234. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.
Analysis of Separation Corridors for Visiting Vehicles from the International Space Station
NASA Technical Reports Server (NTRS)
Zaczek, Mariusz P.; Schrock, Rita R.; Schrock, Mark B.; Lowman, Bryan C.
2011-01-01
The International Space Station (ISS) is a very dynamic vehicle with many operational constraints that affect its performance, operations, and vehicle lifetime. Most constraints are designed to alleviate various safety concerns that are a result of dynamic activities between the ISS and various Visiting Vehicles (VVs). One such constraint that has been in place for Russian Vehicle (RV) operations is the limitation placed on Solar Array (SA) positioning in order to prevent collisions during separation and subsequent relative motion of VVs. An unintended consequence of the SA constraint has been the impacts to the operational flexibility of the ISS resulting from the reduced power generation capability as well as from a reduction in the operational lifetime of various SA components. The purpose of this paper is to discuss the technique and the analysis that were applied in order to relax the SA constraints for RV undockings, thereby improving both the ISS operational flexibility and extending its lifetime for many years to come. This analysis focused on the effects of the dynamic motion that occur both prior to and following RV separations. The analysis involved a parametric approach in the conservative application of various initial conditions and assumptions. These included the use of the worst case minimum and maximum vehicle configurations, worst case initial attitudes and attitude rates, and the worst case docking port separation dynamics. Separations were calculated for multiple ISS docking ports, at varied deviations from the nominal undocking attitudes and included the use of two separate attitude control schemes: continuous free-drift and a post separation attitude hold. The analysis required numerical propagation of both the separation motion and the vehicle attitudes using 3-degree-of-freedom (DOF) relative motion equations coupled with rigid body rotational dynamics to generate a large set of separation trajectories.
Nichols, J Tyler; Krueger, Paul S
2012-09-01
Recent results have demonstrated that pulsed-jet propulsion can achieve propulsive efficiency greater than that for steady jets when short, high frequency pulses are used, and the pulsed-jet advantage increases as Reynolds number decreases into the intermediate range (∼50). An important aspect of propulsive performance, however, is the vehicle configuration. The nozzle configuration influences the jet speed and, in the case of pulsed-jets, the formation of the vortex rings with each jet pulse, which have important effects on thrust. Likewise, the hull configuration influences the vehicle speed through its effect on drag. To investigate these effects, several flow inlet, nozzle, and hull tail configurations were tested on a submersible, self-propelled pulsed-jet vehicle ('Robosquid' for short) for jet pulse length-to-diameter ratios (L/D) in the range 0.5-6 and pulsing duty cycles (St(L)) of 0.2 and 0.5. For the configurations tested, the vehicle Reynolds number (Re(υ)) ranged from 25 to 110. In terms of propulsive efficiency, changing between forward and aft-facing inlets had little effect for the conditions considered, but changing from a smoothly tapered aft hull section to a blunt tail increased propulsive efficiency slightly due to reduced drag for the blunt tail at intermediate Re(υ). Sharp edged orifices also showed increased vehicle velocity and propulsive efficiency in comparison to smooth nozzles, which was associated with stronger vortex rings being produced by the flow contraction through the orifice. Larger diameter orifices showed additional gains in propulsive efficiency over smaller orifices if the rate of mass flow was matched with the smaller diameter cases, but using the same maximum jet velocity with the larger diameter decreased the propulsive efficiency relative to the smaller diameter cases.
Hydrodynamics of an Under-actuated Plesiosaur-inspired robot
NASA Astrophysics Data System (ADS)
Weymouth, Gabriel; Devereux, Kate; Copsey, Nick; Muscutt, Luke; Downes, Jon; Ganapathisubramani, Bharath
2017-11-01
Underwater vehicles are increasingly important tools for use in science and engineering, but maneuverability and mission life seem to be mutually exclusive goals. Inspired by the unique swimming method of the plesiosaur, which used four flippers of essentially equal size and musculature, we analyzed designed and built an underwater vehicle with the potential for both gliding and active maneuvering modes. Using 2D simulations and strip theory approximation to account for the changing arc length along the flipper span, we studied the wake and forces on the foils and determined the optimum flipper geometry, spacing and kinematics. To reduce mechanical and control complexity and cost, we next studied the impact of under-actuated kinematics. Even after optimizing pivot location and range of motion, leaving the foils free to pitch was found to reduce efficiency by approximately 50%. Based on these specifications, the vehicle was built and tested over a range of free swimming and maneuvering cases using motion tracking equipment. The excellent maneuverability of the under-actuated vehicle validates the concept, and the new platform should enable further detailed experimental measurements in the future.
Airborne rotary separator study
NASA Astrophysics Data System (ADS)
Drnevich, R. F.; Nowobilski, J. J.
1992-12-01
Several air breathing propulsion concepts for future earth-to-orbit transport vehicles utilize air collection and enrichment, and subsequent storage of liquid oxygen for later use in the vehicle mission. Work performed during the 1960's established the feasibility of substantially reducing weight and volume of a distillation type air separator system by operating the distillation elements in high 'g' fields obtained by rotating the separator assembly. The purpose of this study was to evaluate various fuels and fuel combinations with the objective of minimizing the weight and increase the ready alert capability of the plane. Fuels will be used to provide energy as well as act as heat sinks for the on-board heat rejection system. Fuel energy was used to provide power for air separation as well as to produce refrigeration for liquefaction of oxygen enriched air, besides its primary purpose of vehicle propulsion. The heat generated in the cycle was rejected to the fuel and water which is also carried on board the vehicle.The fuels that were evaluated include JP4, methane, and hydrogen. Hydrogen served as a comparison to the JP4 and methane cases.
NASA Astrophysics Data System (ADS)
Prasetyo, H.; Alfatsani, M. A.; Fauza, G.
2018-05-01
The main issue in vehicle routing problem (VRP) is finding the shortest route of product distribution from the depot to outlets to minimize total cost of distribution. Capacitated Closed Vehicle Routing Problem with Time Windows (CCVRPTW) is one of the variants of VRP that accommodates vehicle capacity and distribution period. Since the main problem of CCVRPTW is considered a non-polynomial hard (NP-hard) problem, it requires an efficient and effective algorithm to solve the problem. This study was aimed to develop Biased Random Key Genetic Algorithm (BRKGA) that is combined with local search to solve the problem of CCVRPTW. The algorithm design was then coded by MATLAB. Using numerical test, optimum algorithm parameters were set and compared with the heuristic method and Standard BRKGA to solve a case study on soft drink distribution. Results showed that BRKGA combined with local search resulted in lower total distribution cost compared with the heuristic method. Moreover, the developed algorithm was found to be successful in increasing the performance of Standard BRKGA.
Study on kinematic and compliance test of suspension
NASA Astrophysics Data System (ADS)
Jing, Lixin; Wu, Liguang; Li, Xuepeng; Zhang, Yu
2017-09-01
Chassis performance development is a major difficulty in vehicle research and development, which is the main factor restricting the independent development of vehicles in China. These years, through a large number of studies, chassis engineers have found that the suspension K&C characteristics as a quasi-static characteristic of the suspension provides a technical route for the suspension performance R&D, and the suspension K&C test has become an important means of vehicle benchmarking, optimization and verification. However, the research on suspension K&C test is less in china, and the test conditions and setting requirements vary greatly from OEM to OEM. In this paper, the influence of different settings on the characteristics of the suspension is obtained through experiments, and the causes of the differences are analyzed; in order to fully reflect the suspension characteristics, the author recommends the appropriate test case and settings.
Resource Tracking Model Updates and Trade Studies
NASA Technical Reports Server (NTRS)
Chambliss, Joe; Stambaugh, Imelda; Moore, Michael
2016-01-01
The Resource tracking model has been updated to capture system manager and project manager inputs. Both the Trick/GUNNS RTM simulator and the RTM mass balance spreadsheet have been revised to address inputs from system managers and to refine the way mass balance is illustrated. The revisions to the RTM included addition of a Plasma Pyrolysis Assembly (PPA) to recover hydrogen from Sabatier reactor methane which was vented in the prior version of the RTM. The effect of the PPA on the overall balance of resources in an exploration vehicle is illustrated in the increased recycle of vehicle oxygen. Additionally simulation of EVAs conducted from the exploration module was added. Since the focus of the exploration module is to provide a habitat during deep space operations the EVA simulation approach to EVA is based on ISS EVA protocol and processes. Case studies have been run to show the relative effect of performance changes on vehicle resources.
Design Multi-Sides System Unmanned Surface Vehicle (USV) Rocket
NASA Astrophysics Data System (ADS)
Syam, Rafiudin; Sutresman, Onny; Mappaita, Abdullah; Amiruddin; Wiranata, Ardi
2018-02-01
This study aims to design and test USV multislide forms. This system is excellent for maneuvering on the x-y-z coordinates. The disadvantage of a single side USV is that it is very difficult to maneuver to achieve very dynamic targets. While for multi sides system easily maneuvered though x-y-z coordinates. In addition to security defense purposes, multi-side system is also good for maritime intelligence, surveillance. In this case, electric deducted fan with Multi-Side system so that the vehicle can still operate even in reverse condition. Multipleside USV experiments have done with good results. In a USV study designed to use two propulsions.
Heading the ball: a case of a Le Fort II fracture in a football match.
Akoglu, Ebru; Onur, Ozge; Denizbasi, Arzu; Kosargelir, Mehmet; Akoglu, Haldun; Ibrahim, Abdullah
2011-03-15
Facial injuries can impair a patient's ability to eat, speak and interact with others. Severe injuries occur as a result of interpersonal or domestic violence, or in motor vehicle collisions, including those involving motorcycles and all-terrain vehicles. The authors present a case of LeFort II fracture caused by a collision of opponents while heading the ball in a football match.
Plug-in electric vehicles: future market conditions and adoption rates
2017-01-01
This report, the first of four Issues in Focus articles from the International Energy Outlook 2017, analyzes the effects of uncertainties in the adoption of plug-in electric vehicles (PEVs) on worldwide transportation energy consumption. Uncertainties surrounding consumer acceptance, vehicle cost, policies, and other market conditions could affect future adoption rates of plug-in electric vehicles. Two side cases are presented in this report that assume different levels of PEV adoption and result in different levels of worldwide transportation energy consumption.
The influence of air bags and restraining devices on extremity injuries in motor vehicle collisions.
McGovern, M K; Murphy, R X; Okunski, W J; Wasser, T E
2000-05-01
The influence of air bags and other restraining devices on injury after motor vehicle collisions is not well defined. This study examined the relationship between the use of restraining devices and the incidence of extremity injuries in motor vehicle collisions. A retrospective analysis was performed on motor vehicle collision data submitted to the Pennsylvania Trauma Outcome Study database from 1990 through 1995. Criteria for submission included trauma patients who were admitted to the intensive care unit, who died during hospitalization, who were hospitalized for more than 72 hours, or who were transferred in or out of the receiving hospital. A total of 21,875 patients met these criteria. These patients were analyzed for the presence or absence of upper and lower extremity injuries and were compared based on their use of restraining devices. Restraining devices were categorized into four groups: air bag alone, air bag and seat belt, seat belt or carseat without air bag, and no restraining device. Statistical analysis was performed using the chi-squared test of association. For contingency tables with small expected frequencies, Fisher's exact test was used. Study participants included 11,688 men and 10,185 women with a mean age of 38 +/- 20 years. There were 16,033 drivers and 5,842 passengers. Air bags were deployed in 472 instances. In 297 of these cases, additional restraint was provided with a seat belt. In 6,632 cases, air bags were not deployed; however, patients were restrained with either a seat belt or a carseat. In 14,771 cases, patients were not restrained. When comparing restraining devices as a group vs. no restraint, there was a significant decrease in the incidence of upper (p = 0.018) and lower (p < 0.001) extremity injuries. Air bags, however, were associated with an increased incidence of both upper (p = 0.033) and lower (p = 0.002) extremity injuries when compared with no restraint or when compared among patients who were restrained. As a group, restraining devices decrease the incidence of upper and lower extremity trauma sustained by patients injured in motor vehicle collisions. Air bags, however, are associated with an increased incidence of upper and lower extremity injuries when compared with seat belts alone or when no restraining devices are used.
40 CFR 86.111-94 - Exhaust gas analytical system.
Code of Federal Regulations, 2010 CFR
2010-07-01
... hydrocarbon (THC) (hydrocarbon plus methanol in the case of methanol-fueled vehicles), methane (CH4) (for... methanol for methanol-fueled diesel-cycle vehicles) is shown as part of Figure B94-5 (or Figure B94-6... ionization detector (FID) (heated, 235 °±15 °F (113 °±8 °C) for methanol-fueled vehicles) for the...
Numerical simulation of active track tensioning system for autonomous hybrid vehicle
NASA Astrophysics Data System (ADS)
Mȩżyk, Arkadiusz; Czapla, Tomasz; Klein, Wojciech; Mura, Gabriel
2017-05-01
One of the most important components of a high speed tracked vehicle is an efficient suspension system. The vehicle should be able to operate both in rough terrain for performance of engineering tasks as well as on the road with high speed. This is especially important for an autonomous platform that operates either with or without human supervision, so that the vibration level can rise compared to a manned vehicle. In this case critical electronic and electric parts must be protected to ensure the reliability of the vehicle. The paper presents a dynamic parameters determination methodology of suspension system for an autonomous high speed tracked platform with total weight of about 5 tonnes and hybrid propulsion system. Common among tracked vehicles suspension solutions and cost-efficient, the torsion-bar system was chosen. One of the most important issues was determining optimal track tensioning - in this case an active hydraulic system was applied. The selection of system parameters was performed with using numerical model based on multi-body dynamic approach. The results of numerical analysis were used to define parameters of active tensioning control system setup. LMS Virtual.Lab Motion was used for multi-body dynamics numerical calculation and Matlab/SIMULINK for control system simulation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, Jeongwoo; Elgowainy, Amgad; Wang, Michael
2015-07-14
In this study, we evaluated the impacts of producing HOF with a RON of 100, using a range of ethanol blending levels (E10, E25, and E40), vehicle efficiency gains, and HOF market penetration scenarios (3.4% to 70%), on WTW petroleum use and GHG emissions. In particular, we conducted LP modeling of petroleum refineries to examine the impacts of different HOF production scenarios on petroleum refining energy use and GHG emissions. We compared two cases of HOF vehicle fuel economy gains of 5% and 10% in terms of MPGGE to baseline regular gasoline vehicles. We incorporated three key factors in GREETmore » — (1) refining energy intensities of gasoline components for the various ethanol blending options and market shares, (2) vehicle efficiency gains, and (3) upstream energy use and emissions associated with the production of different crude types and ethanol — to compare the WTW GHG emissions of various HOF/vehicle scenarios with the business-as-usual baseline regular gasoline (87 AKI E10) pathway.« less
Ares Launch Vehicles Lean Practices Case Study
NASA Technical Reports Server (NTRS)
Doreswamy, Rajiv; Self, Timothy A.
2007-01-01
The Ares launch vehicles team, managed by the Ares Projects Office (APO) at NASA Marshall Space Flight Center, has completed the Ares I Crew Launch Vehicle System Requirements Review and System Definition Review and early design work for the Ares V Cargo Launch Vehicle. This paper provides examples of how Lean Manufacturing, Kaizen events, and Six Sigma practices are helping APO deliver a new space transportation capability on time and within budget, while still meeting stringent technical requirements. For example, Lean philosophies have been applied to numerous process definition efforts and existing process improvement activities, including the Ares I-X test flight Certificate of Flight Readiness (CoFR) process, risk management process, and review board organization and processes. Ares executives learned Lean practices firsthand, making the team "smart buyers" during proposal reviews and instilling the team with a sense of what is meant by "value-added" activities. Since the goal of the APO is to field launch vehicles at a reasonable cost and on an ambitious schedule, adopting Lean philosophies and practices will be crucial to the Ares Project's long-term SUCCESS.
NASA Astrophysics Data System (ADS)
Topel, Robert H.
2018-01-01
Economic studies of the value of a new good or product innovation are typically retrospective: after a new good has been developed and marketed to consumers, data on prices and consumer choices can be used to estimate welfare gains. This paper calibrates the prospective welfare gains in the United States from a nascent vehicle platform, fuel cell electric vehicles (FCVs), that may or may not succeed in competition with existing vehicle platforms. Prospective gains are due to three main sources: (1) possibly reduced carbon emissions compared to existing vehicle alternatives; (2) the monopsony benefit to the U.S. from reducing world oil demand and hence the price of oil; (3) national security benefits due to reduced "oil dependence", mitigating the impact of oil price shocks on national income. I find that the benefits of reduced carbon emissions are likely to be quite small because reduced oil demand in the U.S. as only a small impact on world oil consumption and carbon emissions. Net monopsony benefits to U.S. consumers are much larger.
NASA Astrophysics Data System (ADS)
Muliarto, H.; Alhamidi; Syahbandi, M.
2017-06-01
Since the last two years the Institut Teknologi Sumatera to accept new students in large numbers. Increasing the number of students is directly proportional to the increase of private vehicles that enter the campus it is not in line with the policy of the Institut Teknologi Sumatera as Smart, Friendly, and Forest Campus. Institut Teknologi Sumatera as Smart, Friendly, and Forest Campus fact has made some deal with mass public transport, Damri, to provide bus transportation to the Institut Teknologi Sumatera, but the number of bus users is still inferior to the number of private vehicle users. This study was conducted to see the modal transfer of the entire academic community ITERA, from private cars to public transport such as buses, with the addition of transportation costs in the form of parking rates. This study shows the dominant displacement can occur if the respondent charged parking fees of IDR 4.000. Besides the displacement mode of transportation from using private vehicles be using the bus can occur if Trans Lampung fix three systems including bus departure and arrival schedules, facility service providers that support, and the addition of the Bus Trans Lampung.
Impact of Drift on the Vehicle Liftoff Acoustic Environments
NASA Technical Reports Server (NTRS)
Kenny, Jeremy; Giacomoni, Clothilde
2016-01-01
During liftoff a vehicle can drift due to wind, nozzle gimbaling, fly away maneuver, etc... This drift can cause the exhaust plumes to impinge on the deck and cause the noise levels experienced by the vehicle to increase. A small increase in the plume impingement can have a dramatic effect on the noise levels when the vehicle is only a few nozzle diameters from the deck. As the vehicle lifts off the deck the increase in noise levels lessens as the plume impingement increases. Several scale model acoustic tests have been undertaken at Marshall Space Flight Center which had test cases that were used to define the relationship between drift and the noise levels experienced by the vehicle.
Effective Use of Weigh-in-Motion Data : The Netherlands Case Study
DOT National Transportation Integrated Search
2007-10-01
Transportation and law enforcement agencies in the Netherlands have developed a robust weigh-in-motion (WIM) data management system that supports a broad array of vehicle weight regulation and enforcement activities, as well as long-term planning and...
HOV Project Case Studies, History and Institutional Arrangements
DOT National Transportation Integrated Search
1990-12-01
The Texas Transportation Institute (TTI), a part of The Texas A&M University : System, is conducting an assessment of high-occupancy vehicle (HOV) projects : located either on freeways or in separate rights-of-way in North America. The : three-year r...
Gaewsky, James P; Weaver, Ashley A; Koya, Bharath; Stitzel, Joel D
2015-01-01
A 3-phase real-world motor vehicle crash (MVC) reconstruction method was developed to analyze injury variability as a function of precrash occupant position for 2 full-frontal Crash Injury Research and Engineering Network (CIREN) cases. Phase I: A finite element (FE) simplified vehicle model (SVM) was developed and tuned to mimic the frontal crash characteristics of the CIREN case vehicle (Camry or Cobalt) using frontal New Car Assessment Program (NCAP) crash test data. Phase II: The Toyota HUman Model for Safety (THUMS) v4.01 was positioned in 120 precrash configurations per case within the SVM. Five occupant positioning variables were varied using a Latin hypercube design of experiments: seat track position, seat back angle, D-ring height, steering column angle, and steering column telescoping position. An additional baseline simulation was performed that aimed to match the precrash occupant position documented in CIREN for each case. Phase III: FE simulations were then performed using kinematic boundary conditions from each vehicle's event data recorder (EDR). HIC15, combined thoracic index (CTI), femur forces, and strain-based injury metrics in the lung and lumbar vertebrae were evaluated to predict injury. Tuning the SVM to specific vehicle models resulted in close matches between simulated and test injury metric data, allowing the tuned SVM to be used in each case reconstruction with EDR-derived boundary conditions. Simulations with the most rearward seats and reclined seat backs had the greatest HIC15, head injury risk, CTI, and chest injury risk. Calculated injury risks for the head, chest, and femur closely correlated to the CIREN occupant injury patterns. CTI in the Camry case yielded a 54% probability of Abbreviated Injury Scale (AIS) 2+ chest injury in the baseline case simulation and ranged from 34 to 88% (mean = 61%) risk in the least and most dangerous occupant positions. The greater than 50% probability was consistent with the case occupant's AIS 2 hemomediastinum. Stress-based metrics were used to predict injury to the lower leg of the Camry case occupant. The regional-level injury metrics evaluated for the Cobalt case occupant indicated a low risk of injury; however, strain-based injury metrics better predicted pulmonary contusion. Approximately 49% of the Cobalt occupant's left lung was contused, though the baseline simulation predicted 40.5% of the lung to be injured. A method to compute injury metrics and risks as functions of precrash occupant position was developed and applied to 2 CIREN MVC FE reconstructions. The reconstruction process allows for quantification of the sensitivity and uncertainty of the injury risk predictions based on occupant position to further understand important factors that lead to more severe MVC injuries.
Redelmeier, Donald A; Naqib, Faisal; Thiruchelvam, Deva; R Barrett, Jon F
2016-09-20
To assess the incidence of cerebral palsy among children born to mothers who had their pregnancy complicated by a motor vehicle crash. Retrospective longitudinal cohort analysis of children born from 1 April 2002 to 31 March 2012 in Ontario, Canada. Cases defined as pregnancies complicated by a motor vehicle crash and controls as remaining pregnancies with no crash. Subsequent diagnosis of cerebral palsy by age 3 years. A total of 1 325 660 newborns were analysed, of whom 7933 were involved in a motor vehicle crash during pregnancy. A total of 2328 were subsequently diagnosed with cerebral palsy, equal to an absolute risk of 1.8 per 1000 newborns. For the entire cohort, motor vehicle crashes correlated with a 29% increased risk of subsequent cerebral palsy that was not statistically significant (95% CI -16 to +110, p=0.274). The increased risk was only significant for those with preterm birth who showed an 89% increased risk of subsequent cerebral palsy associated with a motor vehicle crash (95% CI +7 to +266, p=0.037). No significant increase was apparent for those with a term delivery (95% CI -62 to +79, p=0.510). A propensity score-matched analysis of preterm births (n=4384) yielded a 138% increased relative risk of cerebral palsy associated with a motor vehicle crash (95% CI +27 to +349, p=0.007), equal to an absolute increase of about 10.9 additional cases per 1000 newborns (18.2 vs 7.3, p=0.010). Motor vehicle crashes during pregnancy may be associated with an increased risk of cerebral palsy among the subgroup of cases with preterm birth. The increase highlights a specific role for traffic safety advice in prenatal care. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Influence of driver nationality on the risk of causing vehicle collisions in Spain.
Lardelli Claret, P; Luna del Castillo, J D; Jiménez Moleón, J J; Bueno Cavanillas, A; García Martín, M; Gálvez Vargas, R
2002-05-01
To estimate the association between driver nationality and the risk of causing a collision between vehicles in motion. Retrospective, matched by collision, case-control study. Collisions that occurred in Spain during the period from 1990 to 1999 were studied. Responsible (case) and non-responsible (control) drivers identified in the databases of the Dirección General de Tráfico (General Traffic Directorate) who were involved in a collisions between two or more four wheeled vehicles in motion, in which only one of the drivers had committed a traffic violation. Crude odds ratios (ORs) for the effect of driver nationality on the risk of causing a collision were significantly higher for foreign drivers than for Spanish drivers, and ranged from a minimum of 1.19 (95% CI 1.09 to 1.29) for Portuguese drivers to a maximum of 2.06 (1.88 to 2.27) for British drivers. Corresponding adjusted ORs were slightly lower, but were still significantly higher than 1 for all nationalities except Italian, Belgian, and American (USA). Adjusted ORs were usually higher for collisions that occurred in urban areas than on open roads. Authorities responsible for traffic safety, and drivers in general, should consider foreign drivers in Spain at particularly high risk for causing collisions, especially in urban areas.
Track-to-track association for object matching in an inter-vehicle communication system
NASA Astrophysics Data System (ADS)
Yuan, Ting; Roth, Tobias; Chen, Qi; Breu, Jakob; Bogdanovic, Miro; Weiss, Christian A.
2015-09-01
Autonomous driving poses unique challenges for vehicle environment perception due to the complex driving environment the autonomous vehicle finds itself in and differentiates from remote vehicles. Due to inherent uncertainty of the traffic environments and incomplete knowledge due to sensor limitation, an autonomous driving system using only local onboard sensor information is generally not sufficiently enough for conducting a reliable intelligent driving with guaranteed safety. In order to overcome limitations of the local (host) vehicle sensing system and to increase the likelihood of correct detections and classifications, collaborative information from cooperative remote vehicles could substantially facilitate effectiveness of vehicle decision making process. Dedicated Short Range Communication (DSRC) system provides a powerful inter-vehicle wireless communication channel to enhance host vehicle environment perceiving capability with the aid of transmitted information from remote vehicles. However, there is a major challenge before one can fuse the DSRC-transmitted remote information and host vehicle Radar-observed information (in the present case): the remote DRSC data must be correctly associated with the corresponding onboard Radar data; namely, an object matching problem. Direct raw data association (i.e., measurement-to-measurement association - M2MA) is straightforward but error-prone, due to inherent uncertain nature of the observation data. The uncertainties could lead to serious difficulty in matching decision, especially, using non-stationary data. In this study, we present an object matching algorithm based on track-to-track association (T2TA) and evaluate the proposed approach with prototype vehicles in real traffic scenarios. To fully exploit potential of the DSRC system, only GPS position data from remote vehicle are used in fusion center (at host vehicle), i.e., we try to get what we need from the least amount of information; additional feature information can help the data association but are not currently considered. Comparing to M2MA, benefits of the T2TA object matching approach are: i) tracks taking into account important statistical information can provide more reliable inference results; ii) the track-formed smoothed trajectories can be used for an easier shape matching; iii) each local vehicle can design its own tracker and sends only tracks to fusion center to alleviate communication constraints. A real traffic study with different driving environments, based on a statistical hypothesis test, shows promising object matching results of significant practical implications.
Influence of driver nationality on the risk of causing vehicle collisions in Spain
Lardelli, C; Luna, D; Jimenez, M; Bueno, C; Garcia, M; Galvez, V
2002-01-01
Study objective: To estimate the association between driver nationality and the risk of causing a collision between vehicles in motion. Design: Retrospective, matched by collision, case-control study. Setting: Collisions that occurred in Spain during the period from 1990 to 1999 were studied. Participants: Responsible (case) and non-responsible (control) drivers identified in the databases of the Dirección General de Tráfico (General Traffic Directorate) who were involved in a collisions between two or more four wheeled vehicles in motion, in which only one of the drivers had committed a traffic violation. Main results: Crude odds ratios (ORs) for the effect of driver nationality on the risk of causing a collision were significantly higher for foreign drivers than for Spanish drivers, and ranged from a minimum of 1.19 (95% CI 1.09 to 1.29) for Portuguese drivers to a maximum of 2.06 (1.88 to 2.27) for British drivers. Corresponding adjusted ORs were slightly lower, but were still significantly higher than 1 for all nationalities except Italian, Belgian, and American (USA). Adjusted ORs were usually higher for collisions that occurred in urban areas than on open roads. Conclusions: Authorities responsible for traffic safety, and drivers in general, should consider foreign drivers in Spain at particularly high risk for causing collisions, especially in urban areas. PMID:11964439
Analysis of developed transition road safety barrier systems.
Soltani, Mehrtash; Moghaddam, Taher Baghaee; Karim, Mohamed Rehan; Sulong, N H Ramli
2013-10-01
Road safety barriers protect vehicles from roadside hazards by redirecting errant vehicles in a safe manner as well as providing high levels of safety during and after impact. This paper focused on transition safety barrier systems which were located at the point of attachment between a bridge and roadside barriers. The aim of this study was to provide an overview of the behavior of transition systems located at upstream bridge rail with different designs and performance levels. Design factors such as occupant risk and vehicle trajectory for different systems were collected and compared. To achieve this aim a comprehensive database was developed using previous studies. The comparison showed that Test 3-21, which is conducted by impacting a pickup truck with speed of 100 km/h and angle of 25° to transition system, was the most severe test. Occupant impact velocity and ridedown acceleration for heavy vehicles were lower than the amounts for passenger cars and pickup trucks, and in most cases higher occupant lateral impact ridedown acceleration was observed on vehicles subjected to higher levels of damage. The best transition system was selected to give optimum performance which reduced occupant risk factors using the similar crashes in accordance with Test 3-21. Copyright © 2013 Elsevier Ltd. All rights reserved.
VEGA Launch Vehicle Dynamic Environment: Flight Experience and Qualification Status
NASA Astrophysics Data System (ADS)
Di Trapani, C.; Fotino, D.; Mastrella, E.; Bartoccini, D.; Bonnet, M.
2014-06-01
VEGA Launch Vehicle (LV) during flight is equipped with more than 400 sensors (pressure transducers, accelerometers, microphones, strain gauges...) aimed to catch the physical phenomena occurring during the mission. Main objective of these sensors is to verify that the flight conditions are compliant with the launch vehicle and satellite qualification status and to characterize the phenomena that occur during flight. During VEGA development, several test campaigns have been performed in order to characterize its dynamic environment and identify the worst case conditions, but only with the flight data analysis is possible to confirm the worst cases identified and check the compliance of the operative life conditions with the components qualification status.Scope of the present paper is to show a comparison of the sinusoidal dynamic phenomena that occurred during VEGA first and second flight and give a summary of the launch vehicle qualification status.
Stein, Christopher; Wallis, Lee; Adetunji, Olufemi
2015-09-19
Response time is viewed as a key performance indicator in most emergency medical services (EMS) systems. To determine the effect of increased emergency vehicle numbers on response time performance for priority 1 incidents in an urban EMS system in Cape Town, South Africa, using discrete-event computer simulation. A simulation model was created, based on input data from part of the EMS operations. Two different versions of the model were used, one with primary response vehicles and ambulances and one with only ambulances. In both cases the models were run in seven different scenarios. The first scenario used the actual number of emergency vehicles in the real system, and in each subsequent scenario vehicle numbers were increased by adding the baseline number to the cumulative total. The model using only ambulances had shorter response times and a greater number of responses meeting national response time targets than models using primary response vehicles and ambulances. In both cases an improvement in response times and the number of responses meeting national response time targets was observed with the first incremental addition of vehicles. After this the improvements rapidly diminished and eventually became negligible with each successive increase in vehicle numbers. The national response time target for urban areas was never met, even with a seven-fold increase in vehicle numbers. The addition of emergency vehicles to an urban EMS system improves response times in priority 1 incidents, but alone is not capable of the magnitude of response time improvement needed to meet the national response time targets.
Zhai, Zhiqiang; Song, Guohua; Lu, Hongyu; He, Weinan; Yu, Lei
2017-09-01
Vehicle-specific power (VSP) has been found to be highly correlated with vehicle emissions. It is used in many studies on emission modeling such as the MOVES (Motor Vehicle Emissions Simulator) model. The existing studies develop specific VSP distributions (or OpMode distribution in MOVES) for different road types and various average speeds to represent the vehicle operating modes on road. However, it is still not clear if the facility- and speed-specific VSP distributions are consistent temporally and spatially. For instance, is it necessary to update periodically the database of the VSP distributions in the emission model? Are the VSP distributions developed in the city central business district (CBD) area applicable to its suburb area? In this context, this study examined the temporal and spatial consistency of the facility- and speed-specific VSP distributions in Beijing. The VSP distributions in different years and in different areas are developed, based on real-world vehicle activity data. The root mean square error (RMSE) is employed to quantify the difference between the VSP distributions. The maximum differences of the VSP distributions between different years and between different areas are approximately 20% of that between different road types. The analysis of the carbon dioxide (CO 2 ) emission factor indicates that the temporal and spatial differences of the VSP distributions have no significant impact on vehicle emission estimation, with relative error of less than 3%. The temporal and spatial differences have no significant impact on the development of the facility- and speed-specific VSP distributions for the vehicle emission estimation. The database of the specific VSP distributions in the VSP-based emission models can maintain in terms of time. Thus, it is unnecessary to update the database regularly, and it is reliable to use the history vehicle activity data to forecast the emissions in the future. In one city, the areas with less data can still develop accurate VSP distributions based on better data from other areas.
A tank-to-wheel analysis tool for energy and emissions studies in road vehicles.
Silva, C M; Gonçalves, G A; Farias, T L; Mendes-Lopes, J M C
2006-08-15
Currently, oil based fuels are the primary energy source of road transport. The growing need for oil independence and CO(2) mitigation has lead to the increasing importance of alternative fuel usage. CO(2) is produced not only as the fuel is used in the vehicle (tank-to-wheel contribution), but also upstream, from the fuel extraction to the refueling station (well-to-tank contribution), and the life cycle of the fuel production (well-to-wheel contribution) must be considered in order to analyse the global impact of the fuel utilization. A road vehicle tank-to-wheel analysis tool that may be integrated with well-to-tank models was developed in the present study. The integration in a demonstration case study allowed to perform a life cycle assessment concerning the utilization of diesel and natural gas fuels in a specific network line of a bus transit company operating in the city of Porto, Portugal.
Multifunctional DNA-gold nanoparticles for targeted doxorubicin delivery.
Alexander, Colleen M; Hamner, Kristen L; Maye, Mathew M; Dabrowiak, James C
2014-07-16
In this report we describe the synthesis, characterization, and cytotoxic properties of DNA-capped gold nanoparticles having attached folic acid (FA), a thermoresponsive polymer (p), and/or poly(ethylene glycol) (PEG) oligomers that could be used to deliver the anticancer drug doxorubicin (DOX) in chemotherapy. The FA-DNA oligomer used in the construction of the delivery vehicle was synthesized through the reaction of the isolated folic acid N-hydroxysuccinimide ester with the amino-DNA and the conjugated DNA product was purified using high performance liquid chromatography (HPLC). This approach ultimately allowed control of the amount of FA attached to the surface of the delivery vehicle. Cytotoxicity studies using SK-N-SH neuroblastoma cells with drug loaded delivery vehicles were carried out using a variety of exposure times (1-48 h) and recovery times (1-72 h), and in order to access the effects of varying amounts of attached FA, in culture media deficient in FA. DOX loaded delivery vehicles having 50% of the DNA strands with attached FA were more cytotoxic than when all of the strands contained FA. Since FA stimulates cell growth, the reduced cytotoxicity of vehicles fully covered with FA suggests that the stimulatory effects of FA can more than compensate for the cytotoxic effects of the drug on the cell population. While attachment of hexa-ethylene glycol PEG(18) to the surface of the delivery vehicle had no effect on cytotoxicity, 100% FA plus the thermoresponsive polymer resulted in IC50 = 0.48 ± 0.01 for an exposure time of 24 h and a recovery time of 1 h, which is an order of magnitude more cytotoxic than free DOX. Confocal microscopic studies using fluorescence detection showed that SK-N-SH neuroblastoma cells exposed to DOX-loaded vehicles have drug accumulation inside the cell and, in the case of vehicles with attached FA and thermoresponsive polymer, the drug appears more concentrated. Since the biological target of DOX is DNA, the latter observation is consistent with the high cytotoxicity of vehicles having both FA and the thermoresponsive polymer. The study highlights the potential of DNA-capped gold nanoparticles as delivery vehicles for doxorubicin in cancer chemotherapy.
Drag Reduction CFD Simulations and Flow Visualization of Light Vehicle-Trailer Systems
NASA Astrophysics Data System (ADS)
Sigurdson, Lorenz; Boyer, Henry; Lange, Carlos F.
2016-11-01
Experiments and CFD were performed to study the effect a deflector had on the flow and drag force associated with a 2010 F-150 truck and cargo trailer Light Vehicle-Trailer System (LVTS). Image Correlation Velocimetry (ICV) on smokewire streaklines measured the velocity field on the model mid-plane. CFD estimated the drag reduction as 13% at a Re of 14,900 with a moving ground-plane, and 17% without. Experiments suggested that the low Re does not diminish the full-scale relevance of the drag reduction results. One low Re effect was the presence of a separation bubble on the hood of the tow vehicle whose size reduced with an increase in Re. Three other characteristic flow patterns were identified: separation off the lead vehicle cab, stagnation of the free-stream on the trailer face for the no-deflector case, and subsequent separation at the trailer front corner. Comparisons of the ICV and CFD results with no deflector indicated good agreement in the direction of the velocity vectors, and the smoke streaklines and CFD streamlines also agreed well. However, for the deflector case, the CFD found an entirely different topological solution absent in the experiment. A pair of vertically-oriented mid-plane vortices were wrapped around the front of the trailer. Support from the Canadian Natural Sciences and Engineering Research Council Grant 41747 is gratefully acknowledged.
NASA Astrophysics Data System (ADS)
Jacobson, M. Z.; Colella, W. G.; Golden, D. M.
2004-12-01
The purpose of this study was to examine the potential effects on U.S. air pollution and regional climate of switching the current U.S. fleet of onroad motor vehicles to hydrogen fuel-cell vehicles, where hydrogen was produced by (1) steam-reforming of methane, (2) wind energy, or (3) coal gasification. An additional scenario in which the U.S. fleet was switched to gasoline-electric hybrid vehicles was also examined. The model used was GATOR-GCMOM, a global-through-urban-scale nested and parallelized gas, aerosol, transport, radiation, general-circulation, mesoscale, and ocean model. U.S. emission data for the baseline case were obtained from the U.S. National Emission Inventory, which considers 370,000 stack and fugitive sources, 250,000 area sources, and 1700 categories of onroad and nonroad vehicular sources (including motorcycles, passenger vehicles, trucks, recreational vehicles, construction vehicles, farm vehicles, industrial vehicles, etc.). Emission inventories for each of the three hydrogen scenarios were prepared following a process chain analysis that accounted for energy inputs and pollution outputs during all stages of hydrogen and fossil-fuel production, distribution, storage, and end-use. Emitted pollutants accounted for included CO, CO2, H2, H2O, CH4, speciated ROGs, NOx, NH3, SOx, and speciated particulate matter. Results from the first scenario suggest that switching vehicles in the U.S. to hydrogen produced by steam-reforming of methane may reduce emission of NOx, reactive hydrocarbons, CO, CO2, BC, NO3-, and NH4+, but increase CH4, H2, and SO2 (slightly).The switch may also decrease O3 over most of the U.S. but short-term near-surfaces increases may occur over low-vegetated cities (e.g., in Los Angeles and along the Boston-Washington corridor) due to loss of NOx that otherwise titrates O3. The switch is also estimated to decrease PAN, HCHO, and several other pollutants formed in the atmosphere. Isoprene may increase since fewer oxidants (OH, O3) will be available to destroy it. Results for the scenarios involving hydrogen from wind and coal gasification, and from the hybrid scenario will also be discussed, as will regional climate effects (including effects of H2O). Findings to date suggest that, even under a worst-case scenario of 10% hydrogen leakage, the conversion of the current fleet to hydrogen-fuel cell vehicles, where hydrogen is generated by steam-reforming of methane, may result in a measurable improvement in U.S. air quality.
Modeling Multibody Stage Separation Dynamics Using Constraint Force Equation Methodology
NASA Technical Reports Server (NTRS)
Tartabini, Paul V.; Roithmayr, Carlos M.; Toniolo, Matthew D.; Karlgaard, Christopher D.; Pamadi, Bandu N.
2011-01-01
This paper discusses the application of the constraint force equation methodology and its implementation for multibody separation problems using three specially designed test cases. The first test case involves two rigid bodies connected by a fixed joint, the second case involves two rigid bodies connected with a universal joint, and the third test case is that of Mach 7 separation of the X-43A vehicle. For the first two cases, the solutions obtained using the constraint force equation method compare well with those obtained using industry- standard benchmark codes. For the X-43A case, the constraint force equation solutions show reasonable agreement with the flight-test data. Use of the constraint force equation method facilitates the analysis of stage separation in end-to-end simulations of launch vehicle trajectories
Orbiter/Space lab momentum management for POP orientations
NASA Technical Reports Server (NTRS)
Cox, J. W.
1974-01-01
An angular momentum management scheme applicable to the orbiter/spacelab is described. The basis of the scheme is to periodically maneuver the vehicle through a small angle thereby using the gravity gradient torque to dump momentum from the control moment gyro (CMG) control system. The orbiter is operated with its principal vehicle axis perpendicular to the orbital plane. Numerous case runs were conducted on the hybrid simulation and representative cases are included.
Mahrhauser, D; Nagelreiter, C; Baierl, A; Skipiol, J; Valenta, C
2015-04-01
In this study, the influence of three cosmetically relevant, priorly characterized vehicles on skin hydration, sebum content and transepidermal water loss was investigated. The chosen vehicles included a liposomal pre-formulation, a multiple W/O/W emulsion and a microemulsion gel. The in vivo effects of these vehicles were demonstrated and compared among them. The stability of the prepared vehicles was determined visually, microscopically, rheologically by pH measurements and particle size. Interactions with skin were assessed by non-invasive biophysical techniques using the Corneometer(®), Aqua Flux(®) and Sebumeter, measuring skin hydration, TEWL and skin sebum content, respectively. All vehicles remained stable over an observation period of 6 weeks. The multiple emulsion increased sebum content and skin hydration. In case of the liposomes, each monitored parameter remained almost constant. In contrast, the microemulsion gel lowered skin hydration and increased TEWL values, but even 1 week after termination of the treatment TEWL decreased almost close to control levels. All produced vehicles were proven to remain physically stable over the duration of this study. The used multiple emulsion showed very skin-friendly properties by increasing sebum and skin hydration. Likewise, the liposomal pre-formulation exhibited no negative effects. On the contrary, the investigated microemulsion gel seemed to have skin dehydrating and TEWL increasing features. However, the multiple emulsion as well as liposomes was identified to be well-tolerated vehicles for skin which might qualify them for the use in cosmetic formulations. © 2014 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Asberg, A; Holm, T; Vassbotn, T; Andreassen, A K; Hartmann, A
1999-07-01
Iontophoretic administration of acetylcholine chloride (ACh) and sodium nitroprusside (SNP) combined with laser Doppler skin blood perfusion measurements are used for determination of endothelial-dependent and -independent vasodilation. However, the method is biased by nonspecific vasodilation. The primary aim of this study was to investigate if iontophoresis-induced nonspecific vasodilation may be attenuated by addition of high molar concentrations of NaCl to the iontophoresis solutions. Secondary we investigated the applicability of 5 mol/liter NaCl solution as vehicle for ACh and SNP in this method. Skin perfusion changes were determined for iontophoresis of pure vehicles, deionized water and 5 mol/liter NaCl solution, in 12 healthy volunteers. Responses in skin perfusion to iontophoresis of ACh and SNP dissolved in both vehicles were also investigated. Addition of 5 mol/liter NaCl to deionized water significantly attenuated the nonspecific vasodilation and lowered the potential applied over the skin. The inter- and intraindividual coefficients of variation to ACh and SNP responses became, however, higher using hyperosmolar vehicle. During iontophoresis of SNP (in deionized water) we were unable to distinguish between SNP and vehicle effects. This study shows that the nonspecific vasodilation induced by iontophoresis can be attenuated by addition of 5 mol/liter NaCl, possibly due to lower electrical potential over the skin. However, the variability of the method was not improved. When deionized water was used as vehicle the effect of SNP could not be differentiated from that of the vehicle. This was not the case for ACh. Copyright 1999 Academic Press.
Kinetics of the Shanghai Maglev: Kinematical Analysis of a Real "Textbook" Case of Linear Motion
ERIC Educational Resources Information Center
Hsu, Tung
2014-01-01
A vehicle starts from rest at constant acceleration, then cruises at constant speed for a time. Next, it decelerates at a constant rate.… This and similar statements are common in elementary physics courses. Students are asked to graph the motion of the vehicle or find the velocity, acceleration, and distance traveled by the vehicle from a given…
26 CFR 41.4481-2 - Persons liable for tax.
Code of Federal Regulations, 2010 CFR
2010-04-01
... period; (B) In the case of a vehicle under a suspension of tax described in § 41.4483-3(a), at the time... to whether there was in effect, at the time the vehicle was acquired, a suspension under § 41.4483-3... prior taxable use of the vehicle and whether there was a suspension of tax in the taxable period. If the...
Viano, David C; Parenteau, Chantal S
2016-04-01
This study investigated the change in the fatality and severe injury risks in rear impacts with vehicle model years (MY) grouped prior to, during the phase-in and after the revision to FMVSS 301. FARS and NASS-CDS data were used to determine the injury risks of non-ejected occupants in light vehicles involving non-rollover, rear impacts. The data were analyzed by MY groups: 1996-2001, 2002-2007 and 2008+ to represent the years prior to, during the phase-in and post-revision phase-in of FMVSS 301. The 1996-2013 FARS data were analyzed for rear crashes defined by the initial crash direction (IMPACT1) and direction with most damage (IMPACT2) to the rear. Fatality risk was determined by the number of fatally injured occupants per all occupants with known injury status. The 1994-2013 NASS-CDS was analyzed for rear crashes defined by the damage area variable. The risk of severe injury (MAIS 4+F) was determined as the number of occupants with MAIS 4+F injury per all occupants with known injury status. The distribution of rear crashes was determined by impact location and crash severity. NASS-CDS electronic cases with 2008+ MY vehicles were analyzed to evaluate the vehicle and occupant performance. The fatality risk was 20.6% in the 1996-2001, 17.3% in the 2002-2007 and 15.0% in the 2008+ MY vehicles using FARS with the initial crash direction variable (IMPACT1) to the rear. There was a 27.1% reduction in risk with post-FMVSS 301 vehicles 2008+ MY. The risk was 19.0%, 15.4% and 12.8% with the most damage variable (IMPACT2) to the rear. There was 32.8% reduction in risk with 2008+ MY vehicles. The NASS-CDS analysis showed that the risk of severe injury (MAIS 4+F) was 0.27±0.05% for 1996-2001, 0.30±0.13% for 2002-2007 and 0.08±0.04% for 2008+ MY year vehicles. There was a 70.2% reduction in the risk for severe injury with 2008+ MY vehicles. The NASS-CDS case review of MAIS 4+F injury in rear impacts of 2008+ MY vehicles that comply with the revised FMVSS 301 indicated that the crashes were very severe and generally involved significant 2nd row intrusion. The revision to FMVSS 301 has effectively reduced the risks for fatal and severe injury in vehicles compliant with the revision (2008+ MY). The reduction was 27.1-32.8% in fatality risk using FARS data and 70.2% in severe injury risk using the NASS-CDS when compared to vehicles prior to the phase-in of the revised FMVSS 301 (1996-2001 MY vehicles). It is not possible to parse the effects of other design changes in seats and restraint systems that also increased safety over the study years. Copyright © 2015 Elsevier Ltd. All rights reserved.
Policy Discourses and Changing Practice: Diversity and the University-College
ERIC Educational Resources Information Center
Chan, Adrienne S.
2005-01-01
This study reports the results of research with respect to policy and diversity, as part of a larger case study of a Canadian university-college. The study details an examination of policy discourses as a vehicle for institutional change and provides insights into the everyday experiences of educators, their perspectives on policy and change, and…
"Your Writing, Not My Writing": Discourse Analysis of Student Talk about Writing
ERIC Educational Resources Information Center
Hales, Patrick D.
2017-01-01
Student voice is a difficult concept to capture in research. This study attempts to provide a vehicle for understanding student perceptions about writing and writing instruction through a case study supported by discourse analysis of student talk. The high school students in this study participated in interviews and focus groups about their…
Investigations related to the epidemic strain involved in the French listeriosis outbreak in 1992.
Jacquet, C; Catimel, B; Brosch, R; Buchrieser, C; Dehaumont, P; Goulet, V; Lepoutre, A; Veit, P; Rocourt, J
1995-01-01
Two hundred seventy-nine cases of human listeriosis (92 pregnancy-related cases and 187 non-pregnancy-related cases) caused by a serovar 4b and phagovar 2389:2425:3274:2671:47:108:340 strain were identified in France between March and December 1992. Epidemiological investigations included a case-control study (not described here) and microbiological analyses of foods. Results of the case-control study and characterization of food isolates identified pork tongue in jelly, a ready-to-eat meat product, as the major vehicle of this outbreak, and to a lesser extent, delicatessen products contaminated secondarily during handling in food stores. As far as serotyping, phage typing, DNA macrorestriction pattern analysis (obtained by pulsed-field gel electrophoresis [PFGE]), and ribotyping are concerned, this epidemic strain is phenotypically and genomically closely related to strains responsible for major outbreaks of listeriosis previously observed in Europe and North America. The epidemic strain sensu stricto as defined by PFGE (2/1/3) displayed the same serovar, phagovar, ribovar, and ApaI and NotI PFGE patterns as the epidemic strains from outbreaks in Switzerland, California, and Denmark, but it consistently showed differences in the SmaI PFGE profile. This information greatly contributed to the identification of the major food vehicle (pork tongue in jelly) and further allowed exclusion of other foods (cheese) as possible sources of this major listeriosis epidemic. PMID:7793944
Effects on biological systems of reflected light from a satellite power system
NASA Technical Reports Server (NTRS)
White, M.
1981-01-01
Light reflection produced by the satellite power system and the possible effects of that light on the human eye, plants, and animals were studied. For the human eye, two cases of reflected light, might cause eye damage if viewed for too long. These cases are: (1) if, while in low Earth orbit, the orbital transfer vehicle is misaligned to reflect the Sun to Earth there exists a maximum safe fixation time for the naked eye of 42.4 secs; (2) reflection from the aluminum paint on the back of the orbital transfer vehicle, while in or near low Earth orbit, can be safely viewed by the naked eye for 129 sec. For plants and animals the intensity and timing of light are not a major problem. Ways for reducing and/or eliminating the irradiances are proposed.
Elliott, Michael R; Kallan, Michael J; Durbin, Dennis R; Winston, Flaura K
2006-06-01
To provide an estimate of benefit, if any, of child restraint systems over seat belts alone for children aged from 2 through 6 years. Cohort study. A sample of children in US passenger vehicle crashes was obtained from the National Highway Transportation Safety Administration by combining cases involving a fatality from the US Department of Transportation Fatality Analysis Reporting System with a probability sample of cases without a fatality from the National Automotive Sampling System. Children in tow-away [corrected] crashes occurring between 1998 and 2003. Use of child restraint systems (rear-facing and forward-facing car seats, and shield and belt-positioning booster seats) vs seat belts. Potentially confounding variables included seating position, vehicle type, model year, driver and passenger ages, and driver survival status. Death of child passengers from injuries incurred during the crash. Compared with seat belts, child restraints, when not seriously misused (eg, unattached restraint, child restraint system harness not used, 2 children restrained with 1 seat belt) were associated with a 28% reduction in risk for death (relative risk, 0.72; 95% confidence interval, 0.54-0.97) in children aged 2 through 6 years after adjusting for seating position, vehicle type, model year, driver and passenger ages, and driver survival status. When including cases of serious misuse, the effectiveness estimate was slightly lower (21%) (relative risk, 0.79; 95% confidence interval, 0.59-1.05). Based on these findings as well as previous epidemiological and biomechanical evidence for child restraint system effectiveness in reducing nonfatal injury risk, efforts should continue to promote use of child restraint systems through improved laws and with education and disbursement programs.
NASA Astrophysics Data System (ADS)
Oleksowicz, Selim A.; Burnham, Keith J.; Southgate, Adam; McCoy, Chris; Waite, Gary; Hardwick, Graham; Harrington, Cian; McMurran, Ross
2013-05-01
The sustainable development of vehicle propulsion systems that have mainly focused on reduction of fuel consumption (i.e. CO2 emission) has led, not only to the development of systems connected with combustion processes but also to legislation and testing procedures. In recent years, the low carbon policy has made hybrid vehicles and fully electric vehicles (H/EVs) popular. The main virtue of these propulsion systems is their ability to restore some of the expended energy from kinetic movement, e.g. the braking process. Consequently new research and testing methods for H/EVs are currently being developed. This especially concerns the critical 'use-cases' for functionality tests within dynamic events for both virtual simulations, as well as real-time road tests. The use-case for conventional vehicles for numerical simulations and road tests are well established. However, the wide variety of tests and their great number (close to a thousand) creates a need for selection, in the first place, and the creation of critical use-cases suitable for testing H/EVs in both virtual and real-world environments. It is known that a marginal improvement in the regenerative braking ratio can significantly improve the vehicle range and, therefore, the economic cost of its operation. In modern vehicles, vehicle dynamics control systems play the principal role in safety, comfort and economic operation. Unfortunately, however, the existing standard road test scenarios are insufficient for H/EVs. Sector knowledge suggests that there are currently no agreed tests scenarios to fully investigate the effects of brake blending between conventional and regenerative braking as well as the regenerative braking interaction with active driving safety systems (ADSS). The paper presents seven manoeuvres, which are considered to be suitable and highly informative for the development and examination of H/EVs with regenerative braking capability. The critical manoeuvres presented are considered to be appropriate for examination of the regenerative braking mode according to ADSS. The manoeuvres are also important for investigation of regenerative braking system properties/functionalities that are specified by the legal requirements concerning H/EVs braking systems. The last part of this paper shows simulation results for one of the proposed manoeuvres that explicitly shows the usefulness of the manoeuvre.
Launch Vehicle Performance for Bipropellant Propulsion Using Atomic Propellants With Oxygen
NASA Technical Reports Server (NTRS)
Palaszewski, Bryan
2000-01-01
Atomic propellants for bipropellant launch vehicles using atomic boron, carbon, and hydrogen were analyzed. The gross liftoff weights (GLOW) and dry masses of the vehicles were estimated, and the 'best' design points for atomic propellants were identified. Engine performance was estimated for a wide range of oxidizer to fuel (O/F) ratios, atom loadings in the solid hydrogen particles, and amounts of helium carrier fluid. Rocket vehicle GLOW was minimized by operating at an O/F ratio of 1.0 to 3.0 for the atomic boron and carbon cases. For the atomic hydrogen cases, a minimum GLOW occurred when using the fuel as a monopropellant (O/F = 0.0). The atomic vehicle dry masses are also presented, and these data exhibit minimum values at the same or similar O/F ratios as those for the vehicle GLOW. A technology assessment of atomic propellants has shown that atomic boron and carbon rocket analyses are considered to be much more near term options than the atomic hydrogen rockets. The technology for storing atomic boron and carbon has shown significant progress, while atomic hydrogen is not able to be stored at the high densities needed for effective propulsion. The GLOW and dry mass data can be used to estimate the cost of future vehicles and their atomic propellant production facilities. The lower the propellant's mass, the lower the overall investment for the specially manufactured atomic propellants.
Scientists from the United States and the Czech Republic recently completed a study to investigate the ambient air quality impact of industrial and motor vehicle sources in Teplice. ir pollution measurements made from 1992 through 1993 provide data on ambient concentrations of su...
A case-control study of forklift and other powered industrial vehicle incidents.
Collins, J W; Smith, G S; Baker, S P; Landsittel, D P; Warner, M
1999-11-01
This study examined risk factors associated with forklift and other powered industrial vehicle (PIV) collision injuries with an emphasis on the design of factory traffic systems, the loading and safety features of PIVs, and the characteristics of the drivers. A case-control study examined risk factors for circumstances of injury-producing PIV incidents at eight automotive manufacturing plants between July 1992 and March 1995. A computerized safety and health surveillance system identified 171 incidents where a PIV (forklift 70%, personnel carriers 15%, other 15%) was involved in a collision incident. Site visits were conducted to collect data regarding the factory environment at the collision site, the PIVs involved in the incidents, and driver characteristics. These data were compared with information collected from a random sample of comparison worksites, PIVs, and PIV drivers who had not been involved in a PIV-related incident in the prior 3 years. In half of the cases (86 of 171), an employee (pedestrian) was struck by a PIV or an object being carried by the PIV. The presence of an obstruction that restricted the aisle width increased the odds of a collision incident 1.89 times (95% CI=1.22, 2.86). The presence of overhead mirrors at intersections and blind corners with limited visibility reduced the odds of a PIV collision incident by a third (OR=0.33, 95% CI=0.16, 0.68). When carrying a load, the odds of a PIV being involved in a collision was 1.58 (95% CI=1.03, 2.41) times greater than an unloaded one. Changes in the factory environment, vehicle safety features, and driver and pedestrian training are suggested to reduce the risk of PIV incidents. Am. J. Ind. Med. 36:522-531, 1999. Published 1999 Wiley-Liss, Inc.
Early Impacts of a Human-in-the-Loop Evaluation in a Space Vehicle Mock-up Facility
NASA Technical Reports Server (NTRS)
Byrne, Vicky; Vos, Gordon; Whitmore, Mihriban
2008-01-01
The development of a new space vehicle, the Orion Crew Exploration Vehicle (CEV), provides Human Factors engineers an excellent opportunity to have an impact early in the design process. This case study highlights a Human-in-the-Loop (HITL) evaluation conducted in a Space Vehicle Mock-Up Facility and will describe the human-centered approach and how the findings are impacting design and operational concepts early in space vehicle design. The focus of this HITL evaluation centered on the activities that astronaut crewmembers would be expected to perform within the functional internal volume of the Crew Module (CM) of the space vehicle. The primary objective was to determine if there are aspects of a baseline vehicle configuration that would limit or prevent the performance of dynamically volume-driving activities (e.g. six crewmembers donning their suits in an evacuation scenario). A second objective was to step through concepts of operations for known systems and evaluate them in integrated scenarios. The functional volume for crewmember activities is closely tied to every aspect of system design (e.g. avionics, safety, stowage, seats, suits, and structural support placement). As this evaluation took place before the Preliminary Design Review of the space vehicle with some designs very early in the development, it was not meant to determine definitely that the crewmembers could complete every activity, but rather to provide inputs that could improve developing designs and concepts of operations definition refinement.
NASA Astrophysics Data System (ADS)
Noda, Masafumi; Takahashi, Tomokazu; Deguchi, Daisuke; Ide, Ichiro; Murase, Hiroshi; Kojima, Yoshiko; Naito, Takashi
In this study, we propose a method for detecting road markings recorded in an image captured by an in-vehicle camera by using a position-dependent classifier. Road markings are symbols painted on the road surface that help in preventing traffic accidents and in ensuring traffic smooth. Therefore, driver support systems for detecting road markings, such as a system that provides warning in the case when traffic signs are overlooked, and supporting the stopping of a vehicle are required. It is difficult to detect road markings because their appearance changes with the actual traffic conditions, e. g. the shape and resolution change. The variation in these appearances depend on the positional relation between the vehicle and the road markings, and on the vehicle posture. Although these variations are quite large in an entire image, they are relatively small in a local area of the image. Therefore, we try to improve the detection performance by taking into account the local variations in these appearances. We propose a method in which a position-dependent classifier is used to detect road markings recorded in images captured by an in-vehicle camera. Further, to train the classifier efficiently, we propose a generative learning method that takes into consideration the positional relation between the vehicle and road markings, and also the vehicle posture. Experimental results showed that the detection performance when the proposed method was used was better than when a method involving a single classifier was used.
Rios-Torres, Jackeline; Liu, Jun; Khattak, Asad
2018-06-14
Here, improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To domore » this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.« less
Collaborative Analysis Tool for Thermal Protection Systems for Single Stage to Orbit Launch Vehicles
NASA Technical Reports Server (NTRS)
Alexander, Reginald Andrew; Stanley, Thomas Troy
1999-01-01
Presented is a design tool and process that connects several disciplines which are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to every other system and in the case of SSTO vehicles with air breathing propulsion, which is currently being studied by the National Aeronautics and Space Administration (NASA); the thermal protection system (TPS) is linked directly to almost every major system. The propulsion system pushes the vehicle to velocities on the order of 15 times the speed of sound in the atmosphere before pulling up to go to orbit which results high temperatures on the external surfaces of the vehicle. Thermal protection systems to maintain the structural integrity of the vehicle must be able to mitigate the heat transfer to the structure and be lightweight. Herein lies the interdependency, in that as the vehicle's speed increases, the TPS requirements are increased. And as TPS masses increase the effect on the propulsion system and all other systems is compounded. To adequately determine insulation masses for a vehicle such as the one described above, the aeroheating loads must be calculated and the TPS thicknesses must be calculated for the entire vehicle. To accomplish this an ascent or reentry trajectory is obtained using the computer code Program to Optimize Simulated Trajectories (POST). The trajectory is then used to calculate the convective heat rates on several locations on the vehicles using the Miniature Version of the JA70 Aerodynamic Heating Computer Program (MINIVER). Once the heat rates are defined for each body point on the vehicle, then insulation thickness that are required to maintain the vehicle within structural limits are calculated using Systems Improved Numerical Differencing Analyzer (SINDA) models. If the TPS masses are too heavy for the performance of the vehicle the process may be repeated altering the trajectory or some other input to reduce the TPS mass.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rios-Torres, Jackeline; Liu, Jun; Khattak, Asad
Here, improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To domore » this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.« less
Assessing the ground vibrations produced by a heavy vehicle traversing a traffic obstacle.
Ducarne, Loïc; Ainalis, Daniel; Kouroussis, Georges
2018-01-15
Despite advancements in alternative transport networks, road transport remains the dominant mode in many modern and developing countries. The ground-borne motions produced by the passage of a heavy vehicle over a geometric obstacle (e.g. speed hump, train tracks) pose a fundamental problem in transport annoyance in urban areas. In order to predict the ground vibrations generated by the passage of a heavy vehicle over a geometric obstacle, a two-step numerical model is developed. The first step involves simulating the dynamic loads generated by the heavy vehicle using a multibody approach, which includes the tyre-obstacle-ground interaction. The second step involves the simulation of the ground wave propagation using a three dimensional finite element model. The simulation is able to be decoupled due to the large difference in stiffness between the vehicle's tyres and the road. First, the two-step model is validated using an experimental case study available in the literature. A sensitivity analysis is then presented, examining the influence of various factors on the generated ground vibrations. Factors investigated include obstacle shape, obstacle dimensions, vehicle speed, and tyre stiffness. The developed model can be used as a tool in the early planning stages to predict the ground vibrations generated by the passage of a heavy vehicle over an obstacle in urban areas. Copyright © 2017 Elsevier B.V. All rights reserved.
Lateral dynamic interaction analysis of a train girder pier system
NASA Astrophysics Data System (ADS)
Xia, H.; Guo, W. W.; Wu, X.; Pi, Y. L.; Bradford, M. A.
2008-12-01
A dynamic model of a coupled train-girder-pier system is developed in this paper. Each vehicle in a train is modeled with 27 degrees-of-freedom for a 4-axle passenger coach or freight car, and 31 for a 6-axle locomotive. The bridge model is applicable to straight and curved bridges. The centrifugal forces of moving vehicles on curved bridges are considered in both the vehicle model and the bridge model. The dynamic interaction between the bridge and train is realized through an assumed wheel-hunting movement. A case study is performed for a test train traversing two straight and two curved multi-span bridges with high piers. The histories of the train traversing the bridges are simulated and the dynamic responses of the piers and the train vehicles are calculated. A field experiment is carried out to verify the results of the analysis, by which the lateral resonant train speed inducing the peak pier-top amplitudes and some other observations are validated.
Replacement model of city bus: A dynamic programming approach
NASA Astrophysics Data System (ADS)
Arifin, Dadang; Yusuf, Edhi
2017-06-01
This paper aims to develop a replacement model of city bus vehicles operated in Bandung City. This study is driven from real cases encountered by the Damri Company in the efforts to improve services to the public. The replacement model propounds two policy alternatives: First, to maintain or keep the vehicles, and second is to replace them with new ones taking into account operating costs, revenue, salvage value, and acquisition cost of a new vehicle. A deterministic dynamic programming approach is used to solve the model. The optimization process was heuristically executed using empirical data of Perum Damri. The output of the model is to determine the replacement schedule and the best policy if the vehicle has passed the economic life. Based on the results, the technical life of the bus is approximately 20 years old, while the economic life is an average of 9 (nine) years. It means that after the bus is operated for 9 (nine) years, managers should consider the policy of rejuvenation.
NASA Astrophysics Data System (ADS)
Gil Gómez, Gaspar L.; Nybacka, Mikael; Drugge, Lars; Bakker, Egbert
2018-01-01
Objective measurements and computer-aided engineering simulations cannot be exploited to their full potential because of the high importance of driver feel in vehicle development. Furthermore, despite many studies, it is not easy to identify the relationship between objective metrics (OM) and subjective assessments (SA), a task further complicated by the fact that SA change between drivers and geographical locations or with time. This paper presents a method which uses two artificial neural networks built on top of each other that helps to close this gap. The first network, based solely on OM, generates a map that groups together similar vehicles, thus allowing a classification of measured vehicles to be visualised. This map objectively demonstrates that there exist brand and vehicle class identities. It also foresees the subjective characteristics of a new vehicle, based on its requirements, simulations and measurements. These characteristics are described by the neighbourhood of the new vehicle in the map, which is made up of known vehicles that are accompanied by word-clouds that enhance this description. This forecast is also extended to perform a sensitivity analysis of the tolerances in the requirements, as well as to validate previously published preferred range of steering feel metrics. The results suggest a few new modifications. Finally, the qualitative information given by this measurement-based classification is complemented with a second superimposed network. This network describes a regression surface that enables quantitative predictions, for example the SA of the steering feel of a new vehicle from its OM.
First Stage Solid Propellant Multi Debris Thermal Analysis
NASA Technical Reports Server (NTRS)
Toleman, Benjamin M.
2011-01-01
The crew launch vehicle considered for the Constellation (Cx) Program utilizes a first stage solid rocket motor. If an abort is initiated in first stage flight the Crew Module (CM) will separate and be pulled away from the launch vehicle via a Launch Abort System (LAS) in order to safely and quickly carry the crew away from the malfunction launch vehicle. Having aborted the mission, the launch vehicle will likely be destroyed via a Flight Termination System (FTS) in order to prevent it from errantly traversing back over land and posing a risk to the public. The resulting launch vehicle debris field, composed primarily of first stage solid propellant, poses a threat to the CM. The harsh radiative thermal environment induced by surrounding burning propellant debris may lead to CM parachute failure. A methodology, detailed herein, has been developed to address this concern and quantify the risk of first stage propellant debris leading to radiative thermal demise of the CM parachutes. Utilizing basic thermal radiation principles, a software program was developed to calculate parachute temperature as a function of time for a given abort trajectory and debris piece trajectory set. Two test cases, considered worst-case aborts with regard to launch vehicle debris environments, were analyzed using the simulation: an abort declared at Mach 1 and an abort declared at maximum dynamic pressure (Max Q). For both cases, the resulting temperature profiles indicated that thermal limits for the parachutes were not exceeded. However, short duration close encounters by single debris pieces did have a significant effect on parachute temperature, with magnitudes on the order of 10 s of degrees Fahrenheit. Therefore while these two test cases did not indicate exceedance of thermal limits, in order to quantify the risk of parachute failure due to radiative effects from the abort environment, a more thorough probability-based analysis using the methodology demonstrated herein must be performed.
First Stage Solid Propellant Multiply Debris Thermal Analysis
NASA Technical Reports Server (NTRS)
Toleman, Benjamin M.
2011-01-01
Destruction of a solid rocket stage of a launch vehicle can create a thermal radiation hazard for an aborting crew module. This hazard was assessed for the Constellation Program (Cx) crew and launch vehicle concept. For this concept, if an abort was initiated in first stage flight, the Crew Module (CM) will separate and be pulled away from the malfunctioning launch vehicle via a Launch Abort System (LAS). Having aborted the mission, the launch vehicle will likely be destroyed via a Flight Termination System (FTS) in order to prevent it from errantly traversing back over land and posing a risk to the public. The resulting launch vehicle debris field, composed primarily of first stage solid propellant, poses a threat to the CM. The harsh radiative thermal environment, caused by surrounding burning propellant debris, may lead to CM parachute failure. A methodology, detailed herein, has been developed to address this concern and to quantify the risk of first stage propellant debris leading to the thermal demise of the CM parachutes. Utilizing basic thermal radiation principles, a software program was developed to calculate parachute temperature as a function of time for a given abort trajectory and debris piece trajectory set. Two test cases, considered worst case aborts with regard to launch vehicle debris environments, were analyzed using the simulation: an abort declared at Mach 1 and an abort declared at maximum dynamic pressure (Max Q). For both cases, the resulting temperature profiles indicated that thermal limits for the parachutes were not exceeded. However, short duration close encounters by single debris pieces did have a significant effect on parachute temperature. Therefore while these two test cases did not indicate exceedance of thermal limits, in order to quantify the risk of parachute failure due to radiative effects from the abort environment, a more thorough probability-based analysis using the methodology demonstrated herein must be performed.
Abanyie, F; Harvey, R R; Harris, J R; Wiegand, R E; Gaul, L; Desvignes-Kendrick, M; Irvin, K; Williams, I; Hall, R L; Herwaldt, B; Gray, E B; Qvarnstrom, Y; Wise, M E; Cantu, V; Cantey, P T; Bosch, S; DA Silva, A J; Fields, A; Bishop, H; Wellman, A; Beal, J; Wilson, N; Fiore, A E; Tauxe, R; Lance, S; Slutsker, L; Parise, M
2015-12-01
The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0-∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.
Suicide by pedestrian versus motor vehicle: a case report.
Rudy, Bruce S
2012-09-01
Suicide is the deliberate act of ending one's own life. Historically, men commit suicide more frequently than do women; however, rates have increased for women worldwide in recent years. Transportation injuries have been widely reported as means of suicide such as operators of motor vehicles or jumpers into the pathway of trains. Few definitive reports exist of pedestrians deliberately jumping into the pathway of a motor vehicle. A security camera demonstrates a pedestrian deliberately entering the pathway of a moving vehicle resulting in death from multiple blunt force trauma.
Punnett, L.
1998-01-01
OBJECTIVE: To evaluate the association between upper extremity soft tissue disorders and exposure to preventable ergonomic stressors in vehicle manufacturing operations. METHODS: A cross sectional study was conducted in one vehicle stamping plant and one engine assembly plant. A standardised physical examination of the upper extremities was performed on all subjects. An interviewer administered questionnaire obtained data on demographics, work history, musculoskeletal symptoms, non-occupational covariates, and psycho-physical (relative intensity) ratings of ergonomic stressors. The primary exposure score was computed by summing the responses to the psychophysical exposure items. Multivariate regression analysis was used to model the prevalence of disorders of the shoulders or upper arms, wrists or hands, and all upper extremity regions (each defined both by symptoms and by physical examination plus symptoms) as a function of exposure quartile. RESULTS: A total of 1315 workers (85% of the target population) was examined. The prevalence of symptom disorders was 22% for the wrists or hands and 15% for the shoulders or upper arms; cases defined on the basis of a physical examination were about 80% as frequent. Disorders of the upper extremities, shoulders, and wrists or hands all increased markedly with exposure score, after adjustment for plant, acute injury, sex, body mass index, systemic disease, and seniority. CONCLUSIONS: Musculoskeletal disorders of the upper extremities were strongly associated with exposure to combined ergonomic stressors. The exposure- response trend was very similar for symptom cases and for physical examination cases. It is important to evaluate all dimensions of ergonomic exposure in epidemiological studies, as exposures often occur in combination in actual workplaces. PMID:9764102
Cheng, Yuan-Hsin; Field, William E; Issa, Salah F; Kelley, Kevin; Heber, Matthew; Turner, Robert
2018-05-07
Since 1978, the Purdue University Agricultural Safety and Health Program has managed a surveillance effort and database to collect information on documented injuries and fatalities in all forms of U.S. agricultural confined spaces. The database currently contains 1,968 cases documented in the U.S. between 1964 and 2016. Of these cases, 174 (8.8%) involved entrapment or suffocation in grain transport vehicles (GTVs), including gravity-flow wagons, semi-truck trailers, and other agricultural transport vehicles that have limited access and are not considered normal work spaces or are classified as confined spaces. These GTV cases represent the overwhelming majority of documented cases involving all forms of agricultural transport vehicles, including forage and manure transport vehicles. Of the incidents documented, 64.3% resulted in fatalities and 71.8% involved children and youth age 20 years and under, when the age was determined. For the GTV cases, the typical victim was male (88.5%), and the average age of the victim was 19.9 (median 12), with over 63.5% of the cases involving children under the age of 15. In numerous incidents, more than one victim became entrapped, including one incident involving five victims. The number of documented cases decreased sharply from a peak of approximately 7 cases per year in the early 1990s to an average of 3.1 cases per year over the past two decades, with no cases documented in 1998 and 2013. However, there is a linear increase in the frequency of incidents since the first case was documented in 1964. This trend is partially due to peaks in 2011 and 2014, when 10 and 9 cases, respectively, were documented, along with more vigilant surveillance methods due to online search capabilities. The general decline, more recently, in the annual number of cases is attributed to increased awareness of the hazards to youth during transport in GTVs, increased use of warnings on GTVs, and the increased size of GTVs, which makes human access more difficult and less practical. Efforts over the past decade to bring attention to the risk of entrapment in GTVs should be recognized as a success of the educational and technological strategies initiated due to earlier high-profile incidents. However, with 6, 10, 9, and 4 cases documented in 2010, 2011, 2014, and 2016, respectively, continued efforts to address the problem are justified. Recommendations for future actions include development of a safety standard for GTVs that includes placement of safety messages on all new GTVs, use of windows above outlets, retrofitting older GTVs with appropriate warnings, and continuing to address the hazard with safety resources targeting all workers exposed to grain handling and transport. Copyright© by the American Society of Agricultural Engineers.
Vented Launch Vehicle Adaptor for a Manned Spacecraft with "Pusher" Launch Abort System
NASA Technical Reports Server (NTRS)
Vandervort, Robert E. (Inventor)
2017-01-01
A system, method, and apparatus for a vented launch vehicle adaptor (LVA) for a manned spacecraft with a "pusher" launch abort system are disclosed. The disclosed LVA provides a structural interface between a commercial crew vehicle (CCV) crew module/service module (CM/SM) spacecraft and an expendable launch vehicle. The LVA provides structural attachment of the module to the launch vehicle. It also provides a means to control the exhaust plume from a pusher-type launch abort system that is integrated into the module. In case of an on-pad or ascent abort, which requires the module to jettison away from the launch vehicle, the launch abort system exhaust plume must be safely directed away from critical and dangerous portions of the launch vehicle in order to achieve a safe and successful jettison.
NASA Astrophysics Data System (ADS)
-Aurel Cherecheş, Ioan; -Ioana Borzan, Adela; -Laurean Băldean, Doru
2017-10-01
Study of construction and wearing process in the case of piston-rings and other significant components from internal combustion engines leads at any time to creative and useful optimizing ideas, both in designing and manufacturing phases. Main objective of the present paper is to realize an interdisciplinary research using advanced methods in piston-rings evaluation of a common vehicle on the streets which is Ford Focus FYDD. Specific objectives are a theoretical study of the idea for advanced analysis method in piston-rings evaluation and an applied research developed in at Technical University from Cluj-Napoca with the motor vehicle caught in the repairing process.
Driving down lane-departure crashes : a national priority
DOT National Transportation Integrated Search
2008-04-01
Of the more than 42,000 people killed on our nations highways : annually, over 25,000almost 60 percentdied in : crashes caused when their vehicles veered from the lane. : In some cases, the vehicle crossed the centerline and was : involved i...
DOT National Transportation Integrated Search
2007-10-02
The objective was to evaluate economic justifications for motor carriers to participate in CVISN deployment. CVISN (Commercial Vehicle Information Systems and Networks) includes: interstate credentials administration (registration and permitting), el...
González, Domingo; Espinosa, María del Mar; Domínguez, Manuel
2017-01-01
Aim The aim of this paper is to present an optimization proposal in the automated guided vehicles design used in hospital logistics, as well as to analyze the impact of its implementation in a real environment. Method This proposal is based on the design of those elements that would allow the vehicles to deliver an extra cart by the towing method. So, the proposal intention is to improve the productivity and the performance of the current vehicles by using a transportation method of combined carts. Results The study has been developed following concurrent engineering premises from three different viewpoints. First, the sequence of operations has been described, and second, a proposal of design of the equipment has been undertaken. Finally, the impact of the proposal has been analyzed according to real data from the Hospital Universitario Rio Hortega in Valladolid (Spain). In this particular case, by the implementation of the analyzed proposal in the hospital a reduction of over 35% of the current time of use can be achieved. This result may allow adding new tasks to the vehicles, and according to this, both a new kind of vehicle and a specific module can be developed in order to get a better performance. PMID:28562681
Meier, Paul J; Cronin, Keith R; Frost, Ethan A; Runge, Troy M; Dale, Bruce E; Reinemann, Douglas J; Detlor, Jennifer
2015-07-21
To examine the national fuel and emissions impacts from increasingly electrified light-duty transportation, we reconstructed the vehicle technology portfolios from two national vehicle studies. Using these vehicle portfolios, we normalized assumptions and examined sensitivity around the rates of electrified vehicle penetration, travel demand growth, and electricity decarbonization. We further examined the impact of substituting low-carbon advanced cellulosic biofuels in place of petroleum. Twenty-seven scenarios were benchmarked against a 50% petroleum-reduction target and an 80% GHG-reduction target. We found that with high rates of electrification (40% of miles traveled) the petroleum-reduction benchmark could be satisfied, even with high travel demand growth. The same highly electrified scenarios, however, could not satisfy 80% GHG-reduction targets, even assuming 80% decarbonized electricity and no growth in travel demand. Regardless of precise consumer vehicle preferences, emissions are a function of the total reliance on electricity versus liquid fuels and the corresponding greenhouse gas intensities of both. We found that at a relatively high rate of electrification (40% of miles and 26% by fuel), an 80% GHG reduction could only be achieved with significant quantities of low-carbon liquid fuel in cases with low or moderate travel demand growth.
NASA Astrophysics Data System (ADS)
Maity, Arnab; Padhi, Radhakant; Mallaram, Sanjeev; Mallikarjuna Rao, G.; Manickavasagam, M.
2016-10-01
A new nonlinear optimal and explicit guidance law is presented in this paper for launch vehicles propelled by solid motors. It can ensure very high terminal precision despite not having the exact knowledge of the thrust-time curve apriori. This was motivated from using it for a carrier launch vehicle in a hypersonic mission, which demands an extremely narrow terminal accuracy window for the launch vehicle for successful initiation of operation of the hypersonic vehicle. The proposed explicit guidance scheme, which computes the optimal guidance command online, ensures the required stringent final conditions with high precision at the injection point. A key feature of the proposed guidance law is an innovative extension of the recently developed model predictive static programming guidance with flexible final time. A penalty function approach is also followed to meet the input and output inequality constraints throughout the vehicle trajectory. In this paper, the guidance law has been successfully validated from nonlinear six degree-of-freedom simulation studies by designing an inner-loop autopilot as well, which enhances confidence of its usefulness significantly. In addition to excellent nominal results, the proposed guidance has been found to have good robustness for perturbed cases as well.
The Spatial Effect of Socio-Economic Demographics on Transit Ridership: a Case Study in New York
DOT National Transportation Integrated Search
2018-03-01
Demand for vehicle and public transportation systems continues to increase in and around major urban centers. This increase is especially pronounced during the morning and evening commutes and is further complicated by the complex spatial interaction...
Analysis of Industry Responses to Federal Regulations in Safety Requirements for New Automobiles
DOT National Transportation Integrated Search
1978-03-01
This report presents findings of an initial study of how the automobile industry has responded to the promulgation of motor vehicle standards by the U.S. goverment. The report examines three safety standards as evaluative cases: MVS 203--Steering col...
Evaluation of traffic-flow monitoring technologies : Cicero-Midway smart corridor case study.
DOT National Transportation Integrated Search
2013-06-01
The original goal of this project was to (1) collect probe-vehicle and sensor data in the region of interest, and : perform cleaning and map matching of the data; and (2) evaluate the accuracy of multiple technologies, either : through direct compari...
LAVA Applications to Open Rotors
NASA Technical Reports Server (NTRS)
Kiris, Cetin C.; Housman, Jeff; Barad, Mike; Brehm, Christoph
2015-01-01
Outline: LAVA (Launch Ascent Vehicle Aerodynamics); Introduction; Acoustics Related Applications; LAVA Applications to Open Rotor; Structured Overset Grids; Cartesian Grid with Immersed Boundary; High Speed Case; High Speed Case with Plate Low Speed Case.
Nonlinear panel flutter in a rarefied atmosphere - Aerodynamic shear stress effects
NASA Technical Reports Server (NTRS)
Resende, Hugo B.
1991-01-01
The panel flutter phenomenon is studied assuming free-molecule flow. This kind of analysis is relevant in the case of hypersonic flight vehicles traveling at high altitudes, especially in the leeward portion of the vehicle. In these conditions the aerodynamic shear can be expected to be considerably larger than the pressure at a given point, so that the effects of such a loading are incorporated into the structural model. This is accomplished by introducing distributed longitudinal and bending moment loads. The former can lead to buckling of the panel, with the second mode in the case of a simply-supported panel playing a important role, and becoming the dominant mode in the solution. The presence of equivalent springs in the longitudinal direction at the panel's ends also becomes of relative importance, even for the evaluation of the linear flutter parameter. Finally, the behavior of the system is studied in the presence of applied compressive forces, that is, classical buckling.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wenzel, Tom P.
This report presents a new approach to analyze the relationship between vehicle mass and risk: tracking fatality risk by vehicle model year and mass, for individual vehicle models. This approach is appealing as it greatly minimizes the influence of driver characteristics and behavior, and crash circumstances, on fatality risk. However, only the most popular vehicle models, with the largest number of fatalities, can be analyzed in this manner. While the analysis of all vehicle models of a given type suggests that there is a relationship between increased mass and fatality risk, analysis of the ten most popular four-door car modelsmore » separately suggests that this relationship is weak: in many cases when the mass of a specific vehicle model is increased societal fatality risk is unchanged or even increases. These results suggest that increasing the mass of an individual vehicle model does not necessarily lead to decreased societal fatality risk.« less
NASA Technical Reports Server (NTRS)
Williams, F. E.; Lemon, R. S.
1974-01-01
The investigation of single actuator failures on the space shuttle solid rocket booster required the analysis of both square pattern and diamond pattern actuator configurations. It was determined that for failures occuring near or prior to the region of maximum dynamic pressure, control gain adjustments can be used to achieve virtually nominal mid-boost vehicle behavior. A distinct worst case failure condition was established near staging that could significantly delay staging. It is recommended that the square pattern be retained as a viable alternative to the baseline diamond pattern because the staging transient is better controlled resulting in earlier staging.
Aerodynamic Interaction between Delta Wing and Hemisphere-Cylinder in Supersonic Flow
NASA Astrophysics Data System (ADS)
Nishino, Atsuhiro; Ishikawa, Takahumi; Nakamura, Yoshiaki
As future space vehicles, Reusable Launch Vehicle (RLV) needs to be developed, where there are two kinds of RLV: Single Stage To Orbit (SSTO) and Two Stage To Orbit (TSTO). In the latter case, the shock/shock interaction and shock/boundary layer interaction play a key role. In the present study, we focus on the supersonic flow field with aerodynamic interaction between a delta wing and a hemisphere-cylinder, which imitate a TSTO, where the clearance, h, between the delta wing and hemisphere-cylinder is a key parameter. As a result, complicated flow patterns were made clear, including separation bubbles.
Evolutionary computing for the design search and optimization of space vehicle power subsystems
NASA Technical Reports Server (NTRS)
Kordon, Mark; Klimeck, Gerhard; Hanks, David; Hua, Hook
2004-01-01
Evolutionary computing has proven to be a straightforward and robust approach for optimizing a wide range of difficult analysis and design problems. This paper discusses the application of these techniques to an existing space vehicle power subsystem resource and performance analysis simulation in a parallel processing environment. Out preliminary results demonstrate that this approach has the potential to improve the space system trade study process by allowing engineers to statistically weight subsystem goals of mass, cost and performance then automatically size power elements based on anticipated performance of the subsystem rather than on worst-case estimates.
NASA Astrophysics Data System (ADS)
Foster, Richard W.
1989-07-01
The application of rocket-based combined cycle (RBCC) engines to booster-stage propulsion, in combination with all-rocket second stages in orbital-ascent missions, has been studied since the mid-1960s; attention is presently given to the case of the 'ejector scramjet' RBCC configuration's application to SSTO vehicles. While total mass delivered to initial orbit is optimized at Mach 20, payload delivery capability to initial orbit optimizes at Mach 17, primarily due to the reduction of hydrogen fuel tankage structure, insulation, and thermal protection system weights.
NASA Technical Reports Server (NTRS)
Anderson, Leif F.; Harrington, Sean P.; Omeke, Ojei, II; Schwaab, Douglas G.
2009-01-01
This is a case study on revised estimates of induced failure for International Space Station (ISS) on-orbit replacement units (ORUs). We devise a heuristic to leverage operational experience data by aggregating ORU, associated function (vehicle sub -system), and vehicle effective' k-factors using actual failure experience. With this input, we determine a significant failure threshold and minimize the difference between the actual and predicted failure rates. We conclude with a discussion on both qualitative and quantitative improvements the heuristic methods and potential benefits to ISS supportability engineering analysis.
Coordinated EV adoption: double-digit reductions in emissions and fuel use for $40/vehicle-year.
Choi, Dong Gu; Kreikebaum, Frank; Thomas, Valerie M; Divan, Deepak
2013-09-17
Adoption of electric vehicles (EVs) would affect the costs and sources of electricity and the United States efficiency requirements for conventional vehicles (CVs). We model EV adoption scenarios in each of six regions of the Eastern Interconnection, containing 70% of the United States population. We develop electricity system optimization models at the multidecade, day-ahead, and hour-ahead time scales, incorporating spatial wind energy modeling, endogenous modeling of CV efficiencies, projections for EV efficiencies, and projected CV and EV costs. We find two means to reduce total consumer expenditure (TCE): (i) controlling charge timing and (ii) unlinking the fuel economy regulations for CVs from EVs. Although EVs provide minimal direct GHG reductions, controlled charging provides load flexibility, lowering the cost of renewable electricity. Without EVs, a 33% renewable electricity standard (RES) would cost $193/vehicle-year more than the reference case (10% RES). Combining a 33% RES, EVs with controlled charging and unlinking would reduce combined electric- and vehicle-sector CO2 emissions by 27% and reduce gasoline consumption by 59% for $40/vehicle-year more than the reference case. Coordinating EV adoption with adoption of controlled charging, unlinked fuel economy regulations, and renewable electricity standards would provide low-cost reductions in emissions and fuel usage.
NASA Technical Reports Server (NTRS)
Tucker, Michael; Meredith, Oliver; Brothers, Bobby
1986-01-01
Several concepts of chemical-propulsion Space Vehicles (SVs) for manned Mars landing missions are presented. For vehicle sizing purposes, several specific missions were chosen from opportunities in the late 1990's and early 2000's, and a vehicle system concept is then described which is applicable to the full range of missions and opportunities available. In general, missions utilizing planetary opposition alignments can be done with smaller vehicles than those utilizing planetary opposition alignments. The conjunction missions have a total mission time of about 3 years, including a required stay-time of about 60 days. Both types of missions might be desirable during a Mars program, the opposition type for early low-risk missions and/or for later unmanned cargo missions, and the conjunction type for more extensive science/exploration missions and/or for Mars base activities. Since the opposition missions appeared to drive the SV size more severely, there were probably more cases examined for them. Some of the concepts presented utilize all-propulsive braking, some utilize and all aerobraking approach, and some are hybrids. Weight statements are provided for various cases. Most of the work was done on 0-g vehicle concepts, but partial-g and 1-g concepts are also provided and discussed. Several options for habitable elements are shown, such as large-diameter modules and space station (SS) types of modules.
Unregulated greenhouse gas and ammonia emissions from current technology heavy-duty vehicles.
Thiruvengadam, Arvind; Besch, Marc; Carder, Daniel; Oshinuga, Adewale; Pasek, Randall; Hogo, Henry; Gautam, Mridul
2016-11-01
The study presents the measurement of carbonyl, BTEX (benzene, toluene, ethyl benzene, and xylene), ammonia, elemental/organic carbon (EC/OC), and greenhouse gas emissions from modern heavy-duty diesel and natural gas vehicles. Vehicles from different vocations that included goods movement, refuse trucks, and transit buses were tested on driving cycles representative of their duty cycle. The natural gas vehicle technologies included the stoichiometric engine platform equipped with a three-way catalyst and a diesel-like dual-fuel high-pressure direct-injection technology equipped with a diesel particulate filter (DPF) and a selective catalytic reduction (SCR). The diesel vehicles were equipped with a DPF and SCR. Results of the study show that the BTEX emissions were below detection limits for both diesel and natural gas vehicles, while carbonyl emissions were observed during cold start and low-temperature operations of the natural gas vehicles. Ammonia emissions of about 1 g/mile were observed from the stoichiometric natural gas vehicles equipped with TWC over all the driving cycles. The tailpipe GWP of the stoichiometric natural gas goods movement application was 7% lower than DPF and SCR equipped diesel. In the case of a refuse truck application the stoichiometric natural gas engine exhibited 22% lower GWP than a diesel vehicle. Tailpipe methane emissions contribute to less than 6% of the total GHG emissions. Modern heavy-duty diesel and natural gas engines are equipped with multiple after-treatment systems and complex control strategies aimed at meeting both the performance standards for the end user and meeting stringent U.S. Environmental Protection Agency (EPA) emissions regulation. Compared to older technology diesel and natural gas engines, modern engines and after-treatment technology have reduced unregulated emissions to levels close to detection limits. However, brief periods of inefficiencies related to low exhaust thermal energy have been shown to increase both carbonyl and nitrous oxide emissions.
NASA Astrophysics Data System (ADS)
Fox, Matthew D.
Advanced automotive technology assessment and powertrain design are increasingly performed through modeling, simulation, and optimization. But technology assessments usually target many competing criteria making any individual optimization challenging and arbitrary. Further, independent design simulations and optimizations take considerable time to execute, and design constraints and objectives change throughout the design process. Changes in design considerations usually require re-processing of simulations and more time. In this thesis, these challenges are confronted through CSU's participation in the EcoCAR2 hybrid vehicle design competition. The complexity of the competition's design objectives leveraged development of a decision support system tool to aid in multi-criteria decision making across technologies and to perform powertrain optimization. To make the decision support system interactive, and bypass the problem of long simulation times, a new approach was taken. The result of this research is CSU's architecture selection and component sizing, which optimizes a composite objective function representing the competition score. The selected architecture is an electric vehicle with an onboard range extending hydrogen fuel cell system. The vehicle has a 145kW traction motor, 18.9kWh of lithium ion battery, a 15kW fuel cell system, and 5kg of hydrogen storage capacity. Finally, a control strategy was developed that improves the vehicles performance throughout the driving range under variable driving conditions. In conclusion, the design process used in this research is reviewed and evaluated against other common design methodologies. I conclude, through the highlighted case studies, that the approach is more comprehensive than other popular design methodologies and is likely to lead to a higher quality product. The upfront modeling work and decision support system formulation will pay off in superior and timely knowledge transfer and more informed design decisions. The hypothesis is supported by the three case studies examined in this thesis.
Increase of stagnation pressure and enthalpy in shock tunnels
NASA Technical Reports Server (NTRS)
Bogdanoff, David W.; Cambier, Jean-Luc
1992-01-01
High stagnation pressures and enthalpies are required for the testing of aerospace vehicles such as aerospace planes, aeroassist vehicles, and reentry vehicles. Among the most useful ground test facilities for performing such tests are shock tunnels. With a given driver gas condition, the enthalpy and pressure in the driven tube nozzle reservoir condition can be varied by changing the driven tube geometry and initial gas fill pressure. Reducing the driven tube diameter yields only very modest increases in reservoir pressure and enthalpy. Reducing the driven tube initial gas fill pressure can increase the reservoir enthalpy significantly, but at the cost of reduced reservoir pressure and useful test time. A new technique, the insertion of a converging section in the driven tube is found to produce substantial increases in both reservoir pressure and enthalpy. Using a one-dimensional inviscid full kinetics code, a number of different locations and shapes for the converging driven tube section were studied and the best cases found. For these best cases, for driven tube diameter reductions of factors of 2 and 3, the reservoir pressure can be increased by factors of 2.1 and 3.2, respectively and the enthalpy can be increased by factors of 1.5 and 2.1, respectively.
ERIC Educational Resources Information Center
Marks, Pia Zeni; Jennings, Brad; Farrell, Barbara; Kennie-Kaulbach, Natalie; Jorgenson, Derek; Sharpe, Jane Pearson; Waite, Nancy
2014-01-01
The convenience and flexibility of online learning clearly make it an attractive option for learners in professional development contexts. There is less clarity, however, about how it fares as a vehicle for enabling the applied, practice-oriented outcomes typically associated with professional development learning. This paper presents a case study…
Precision enhancement of pavement roughness localization with connected vehicles
NASA Astrophysics Data System (ADS)
Bridgelall, R.; Huang, Y.; Zhang, Z.; Deng, F.
2016-02-01
Transportation agencies rely on the accurate localization and reporting of roadway anomalies that could pose serious hazards to the traveling public. However, the cost and technical limitations of present methods prevent their scaling to all roadways. Connected vehicles with on-board accelerometers and conventional geospatial position receivers offer an attractive alternative because of their potential to monitor all roadways in real-time. The conventional global positioning system is ubiquitous and essentially free to use but it produces impractically large position errors. This study evaluated the improvement in precision achievable by augmenting the conventional geo-fence system with a standard speed bump or an existing anomaly at a pre-determined position to establish a reference inertial marker. The speed sensor subsequently generates position tags for the remaining inertial samples by computing their path distances relative to the reference position. The error model and a case study using smartphones to emulate connected vehicles revealed that the precision in localization improves from tens of metres to sub-centimetre levels, and the accuracy of measuring localized roughness more than doubles. The research results demonstrate that transportation agencies will benefit from using the connected vehicle method to achieve precision and accuracy levels that are comparable to existing laser-based inertial profilers.
Sevagan, Gopinath; Zhu, Feng; Jiang, Binhui; Yang, King H
2013-07-01
This article presents the results of a finite element simulation on the occupant head response in an infantry vehicle under two separated loading conditions: (1) blunt impact and (2) blast loading conditions. A Hybrid-III dummy body integrated with a previously validated human head model was used as the surrogate. The biomechanical response of the head was studied in terms of head acceleration due to the impact by a projectile on the vehicle and intracranial pressure caused by blast wave. A series of parametric studies were conducted on the numerical model to analyze the effect of some key parameters, such as seat configuration, impact velocity, and boundary conditions. The simulation results indicate that a properly designed seat and internal surface of the infantry vehicle can play a vital role in reducing the risk of head injury in the current scenarios. Comparison of the kinematic responses under the blunt impact and blast loading conditions reveals that under the current loading conditions, the acceleration pulse in the blast scenario has much higher peak values and frequency than blunt impact case, which may reflect different head response characteristics.
Launch Vehicle Assessment for Space Solar Power
NASA Technical Reports Server (NTRS)
Olds, John R.
1998-01-01
A recently completed study at Georgia Tech examined various launch vehicle options for deploying a future constellation of Space Solar Power satellites of the Suntower configuration. One of the motivations of the study was to determine whether the aggressive $400/kg launch price goal established for SSP package delivery would result in an attractive economic scenario for a future RLV developer. That is, would the potential revenue and traffic to be derived from a large scale SSP project be enough of an economic "carrot" to attract an RLV company into developing a new, low cost launch vehicle to address this market. Preliminary results presented in the attached charts show that there is enough economic reward for RLV developers, specifically in the case of the latest large GEO-based Suntower constellations (over 15,500 MT per year delivery for 30 years). For that SSP model, internal rates of return for the 30 year economic scenario exceed 22%. However, up-front government assistance to the RLV developer in terms of ground facilities, operations technologies, guaranteed low-interest rate loans, and partial offsets of some vehicle development expenses is necessary to achieve these positive results. This white paper is meant to serve as a companion to the data supplied in the accompanying charts. It's purpose is to provide more detail on the vehicles and design processes used, to highlight key decisions and issues, and to emphasize key results from each phase of the Georgia Tech study.
Flood Impacts on People: from Hazard to Risk Maps
NASA Astrophysics Data System (ADS)
Arrighi, C.; Castelli, F.
2017-12-01
The mitigation of adverse consequences of floods on people is crucial for civil protection and public authorities. According to several studies, in the developed countries the majority of flood-related fatalities occurs due to inappropriate high risk behaviours such as driving and walking in floodwaters. In this work both the loss of stability of vehicles and pedestrians in floodwaters are analysed. Flood hazard is evaluated, based on (i) a 2D inundation model of an urban area, (ii) 3D hydrodynamic simulations of water flows around vehicles and human body and (iii) a dimensional analysis of experimental activity. Exposure and vulnerability of vehicles and population are assessed exploiting several sources of open GIS data in order to produce risk maps for a testing case study. The results show that a significant hazard to vehicles and pedestrians exists in the study area. Particularly high is the hazard to vehicles, which are likely to be swept away by flood flow, possibly aggravate damages to structures and infrastructures and locally alter the flood propagation. Exposure and vulnerability analysis identifies some structures such as schools and public facilities, which may attract several people. Moreover, some shopping facilities in the area, which attract both vehicular and pedestrians' circulation are located in the highest flood hazard zone.The application of the method demonstrates that, at municipal level, such risk maps can support civil defence strategies and education to active citizenship, thus contributing to flood impact reduction to population.
Influence of unsprung weight on vehicle ride quality
NASA Astrophysics Data System (ADS)
Hrovat, D.
1988-08-01
In the first part of this paper, a simple quarter-car, two-degree-of-freedom (2 DOF) vehicle model is used to investigate potential benefits and adaptive control capabilities of active suspensions. The results of this study indicate that, with an active suspension, it is possible to trade each 1% increase in tire deflection with a circa 1% decrease in r.m.s. sprung mass acceleration. This can be used for adaptive suspension tuning based on varying road/speed conditions. The second part of this paper is concerned with the influence of unsprung mass on optimal vibration isolation for the case of a linear 2 DOF, quarter-car model. In the study, it is assumed that the tire stiffness and geometry remain the same while unsprung mass is changed. The comprehensive computer analysis shows that, for active suspensions, both ride and handling can be improved by reducing the unsprung mass. In particular, when the total vehicle mass is kept constant, every 10% reduction in unsprung mass contributes to a circa 6% reduction in r.m.s. sprung mass acceleration for the same level of wheel-hop. For active suspension vehicles, this gives an added incentive for reducing the unsprung weight through the usage of, for example, aluminum wheels and lightweight composite materials. Although used primarily in the context of automotive applications, the results of this study are generic to similar 2 DOF structures in other areas of vibration isolation, ranging from computer peripherals to off-road vehicles.
Head impact contact points for restrained child occupants.
Arbogast, Kristy B; Wozniak, Samantha; Locey, Caitlin M; Maltese, Matthew R; Zonfrillo, Mark R
2012-01-01
Head injuries are the most common injuries sustained by children in motor vehicle crashes regardless of age, restraint, and crash direction. For rear seat occupants, the interaction of the subject with the seat back and the vehicle side interior structures has been previously highlighted. In order to advance this knowledge to the development of countermeasures, a summary of vehicle components that contributed to these injuries is needed. Therefore, the objective of this study was to create a contact map of the vehicle interior for head and face injuries to rear-seated restrained children in front crashes. The Crash Injury Research and Engineering Network (CIREN) was queried for rear-seated, restrained child occupants (age 0-15 years) in forward-facing child restraints, booster seats, or lap and shoulder belts who sustained an AIS2+ head and/or face injury in a frontal motor vehicle crash. Cases were analyzed to describe injury patterns and injury causation scenarios. A contact point map was developed to summarize the vehicle components related to injury causation of the head/face injury. Twenty-one cases met the combined inclusion and exclusion criteria. Seven of the child occupants were restrained in forward-facing child restraints, 2 in belt-positioning booster seats, and 12 in lap and shoulder belts. There were 28 head and 17 facial injuries. For left rear occupants, the most common contact point was the pillar in front of the occupant's seat row; that is, B-pillar for second-row occupants, indicating a leftward kinematics. For right rear occupants, due to differences in crash dynamics, the most common contact point location was the passenger's seat back, suggesting that these occupants moved predominantly forward. Contact points associated with head/face injury for restrained children 0 to 15 years in frontal crashes have been delineated. In a majority of the cases, the head/face injury was the most severe injury and severe injuries to other body regions were uncommon, suggesting that efforts to mitigate head injuries for these occupants would greatly improve their overall safety. The majority of the head/face contact points were to the first row seat back and B-pillar. In these frontal crashes, the importance of head/face contact with the vehicle side structure suggests that deploying a curtain air bag in frontal impacts may help manage the energy of impact. These data advance the current understanding of injury patterns and causation in frontal crashes involving restrained rear-row occupants and can be used to develop solutions to mitigate the injuries sustained. Copyright © 2012 Taylor & Francis Group, LLC
Houston managed lanes case study : the evolution of the Houston HOV system
DOT National Transportation Integrated Search
2003-09-01
A nine-mile contraflow High Occupancy Vehicle (HOV) lane on the I-45 North Freeway in Houston, Texas was implemented as a demonstration project in 1979. This demonstration borrowed an off-peak direction traffic lane for use by buses and vanpools in t...
Veal Liver as Food Vehicle for Human Campylobacter Infections.
Gaulin, Colette; Ramsay, Danielle; Dion, Réjean; Simard, Marc; Gariépy, Céline; Levac, Éric; Hammond-Collins, Karon; Michaud-Dumont, Maude; Gignac, Mélanie; Fiset, Marc
2018-06-01
A matched case-control study in Quebec, Canada, evaluated consumption of veal liver as a risk factor for campylobacteriosis. Campylobacter was identified in 28 of 97 veal livers collected concurrently from slaughterhouses and retailers. Veal liver was associated with human Campylobacter infection, particularly when consumed undercooked.
DOT National Transportation Integrated Search
2012-11-01
This report summarizes background research and presents an analysis template for analyzing the emissions from vehicle delay at land ports of entry along the United States-Mexico border. The analyses template is presented along with two case studies. ...
DOT National Transportation Integrated Search
2004-08-01
The number of journal articles, books, and research related to rural transit has : increased somewhat in the past decade; however, there has been little transit research on : rural Maine. Maine citizens rely heavily on personal vehicles for transport...
Driver-initiated distractions: examining strategic adaptation for in-vehicle task initiation.
Horrey, William J; Lesch, Mary F
2009-01-01
Today, drivers are faced with many in-vehicle activities that are potentially distracting. In many cases, they are not passive recipients of these tasks; rather, drivers decide whether or not (or how) to perform them. In this study, we examined whether drivers, given knowledge of the upcoming road demands, would strategically delay performing in-vehicle activities until demands were reduced. Twenty drivers drove an instrumented van around a closed track that was divided into sections of varying demands and difficulty. Drivers were asked to perform one of four in-vehicle tasks (e.g., phone conversation; read a text message; find an address; pick up an object on the floor); however, they were free to decide when to initiate these tasks, provided they finish them before a given deadline. Although drivers were fully aware of the relative demands of the road, they did not tend to strategically postpone tasks--a finding that was consistent across the different tasks (p >.05). Rather, drivers tended to initiate tasks regardless of the current driving conditions. This strategy frequently led to driving errors. Given the control that drivers have over many in-vehicle distractions, interventions that focus on strategic decisions and planning may have merit.
The development of a lightweight modular compliant surface bio-inspired robot
NASA Astrophysics Data System (ADS)
Stone, David L.; Cranney, John
2004-09-01
The DARPA Sponsored Compliant Surface Robotics (CSR) program pursues development of a high mobility, lightweight, modular, morphable robot for military forces in the field and for other industrial uses. The USTLAB effort builds on proof of concept feasibility studies and demonstration of a 4, 6, or 8 wheeled modular vehicle with articulated leg-wheel assemblies. In Phase I, basic open plant stability was proven for climbing over obstacles of ~18 inches high and traversing ~75 degree inclines (up, down, or sideways) in a platform of approximately 15 kilograms. At the completion of Phase II, we have completed mechanical and electronics engineering design and achieved changes which currently enable future work in active articulation, enabling autonomous reconfiguration for a wide variety of terrains, including upside down operations (in case of flip over), and we have reduced platform weight by one third. Currently the vehicle weighs 10 kilograms and will grow marginally as additional actuation, MEMS based organic sensing, payload, and autonomous processing is added. The CSR vehicle"s modular spider-like configuration facilitates adaptation to many uses and compliance over rugged terrain. The developmental process and the vehicle characteristics will be discussed.
Nie, Jin; Yang, Jikuang
2014-10-01
Like pedestrians, bicyclists are vulnerable road users, representing a population with a high risk of fatal and severe injuries in traffic accidents as they are unprotected during vehicle collisions. The objective of this study is to investigate the kinematics response of bicyclists and the correlation of the injury severity with vehicle impact speed. Twenty-four car-bicyclist cases with detailed information were selected for accident reconstruction using mathematical models, which was implemented in the MADYMO program. The dynamic response of bicyclists in the typical impact configuration and the correlation of head impact conditions were analyzed and discussed with respect to the head impact speed, time of head impact and impact angle of bicyclists to vehicle impact speed. Furthermore, the injury distribution of bicyclists and the risk of head injuries and fractures of lower limbs were investigated in terms of vehicle impact speed. The results indicate that wrap-around distance (WAD), head impact speed, time of head impact, head impact angle, and throw-out distance (TOD) of the bicyclists have a strong relationship with vehicle impact speed. The vehicle impact speed corresponding to a 50% probability of head AIS 2+ injuries, head AIS 3+ injuries, and lower limb fracture risk for bicyclists is 53.8km/h, 58.9km/h, and 41.2km/h, respectively. A higher vehicle impact speed produces a higher injury risk to bicyclist. The results could provide background knowledge for the establishment or modification of pedestrian regulations considering bicyclist protection as well as being helpful for developing safety measures and protection devices for bicyclists. Copyright © 2014 Elsevier Ltd. All rights reserved.
Ahn, Yongjun; Yeo, Hwasoo
2015-01-01
The charging infrastructure location problem is becoming more significant due to the extensive adoption of electric vehicles. Efficient charging station planning can solve deeply rooted problems, such as driving-range anxiety and the stagnation of new electric vehicle consumers. In the initial stage of introducing electric vehicles, the allocation of charging stations is difficult to determine due to the uncertainty of candidate sites and unidentified charging demands, which are determined by diverse variables. This paper introduces the Estimating the Required Density of EV Charging (ERDEC) stations model, which is an analytical approach to estimating the optimal density of charging stations for certain urban areas, which are subsequently aggregated to city level planning. The optimal charging station's density is derived to minimize the total cost. A numerical study is conducted to obtain the correlations among the various parameters in the proposed model, such as regional parameters, technological parameters and coefficient factors. To investigate the effect of technological advances, the corresponding changes in the optimal density and total cost are also examined by various combinations of technological parameters. Daejeon city in South Korea is selected for the case study to examine the applicability of the model to real-world problems. With real taxi trajectory data, the optimal density map of charging stations is generated. These results can provide the optimal number of chargers for driving without driving-range anxiety. In the initial planning phase of installing charging infrastructure, the proposed model can be applied to a relatively extensive area to encourage the usage of electric vehicles, especially areas that lack information, such as exact candidate sites for charging stations and other data related with electric vehicles. The methods and results of this paper can serve as a planning guideline to facilitate the extensive adoption of electric vehicles.
The risk of a safety-critical event associated with mobile device use in specific driving contexts.
Fitch, Gregory M; Hanowski, Richard J; Guo, Feng
2015-01-01
We explored drivers' mobile device use and its associated risk of a safety-critical event (SCE) in specific driving contexts. Our premise was that the SCE risk associated with mobile device use increases when the driving task becomes demanding. Data from naturalistic driving studies involving commercial motor vehicle drivers and light vehicle drivers were partitioned into subsets representative of specific driving contexts. The subsets were generated using data set attributes that included level of service and relation to junction. These attributes were selected based on exogenous factors known to alter driving task demands. The subsets were analyzed using a case-cohort approach, which was selected to complement previous investigations of mobile device SCE risk using naturalistic driving data. Both commercial motor vehicle and light vehicle drivers varied as to how much they conversed on a mobile device but did not vary their engagement in visual-manual subtasks. Furthermore, commercial motor vehicle drivers conversed less frequently as the driving task demands increased, whereas light vehicle drivers did not. The risk of an SCE associated with mobile device use was dependent on the subtask performed and the driving context. Only visual-manual subtasks were associated with an increased SCE risk, whereas conversing was associated with a decreased risk in some driving contexts. Drivers' engagement in mobile device subtasks varies by driving context. The SCE risk associated with mobile device use is dependent on the types of subtasks performed and the driving context. The findings of this exploratory study can be applied to the design of driver-vehicle interfaces that mitigate distraction by preventing visual-manual subtasks while driving.
FAST20XX: Achievements On European Suborbital Space Flight
NASA Astrophysics Data System (ADS)
Mack, A.; Steelant, J.; Adirim, H.; Lentsch, A.; Marini, M.; Pilz, N.
2011-05-01
In Europe, the EC co-funded project FAST20XX aims at exploring the borderline between aviation and space by investigating suborbital vehicles. The main focus is the identification and mastering of critical technologies for such vehicles rather than the vehicle development itself. Besides the objectives and overall layout of the project, the paper addresses also the progress made during the first period of the project. Two vehicle concepts are considered. A first one is a space vehicle launched from an airplane providing a low-energy ballistic flight experience using hybrid propulsion. The second is a vertically starting two-stage rocket space vehicle system concept taken as a basis to identify the conditions and constraints experienced during high- energy suborbital ultra-fast transport. The paper mainly discusses the two actual reference vehicles and the technical aspects of prerequisites for commercial operation including safety, human spaceflight, business cases, environmental and legal issues.
Suicide and murder-suicide involving automobiles.
Pridmore, Saxby; Varbanov, Svetlin; Sale, Ian
2017-02-01
We aim to explore the phenomenon of suicide by driving one vehicle into another, and draw attention to the cost to occupants of targeted vehicles. We examined academic literature, court and newspaper reports, and online sources. Driver suicide may be achieved by colliding with a fixed object or another vehicle. When a second vehicle is targeted, the occupants of that vehicle experience property loss, and potentially physical and psychiatric injury, or death. Driver suicides are associated with death of another person, in 11.3% of cases. Some suicidal individuals are able to act with great consideration for the consequences of their actions. Every effort must be made to help suicidal people with mental disorders or other predicaments. There is a need for public discussion of suicide by targeting an oncoming vehicle. It is less likely that suicide drivers who target other vehicles are unable to choose and more likely they have not considered the consequences of their actions.
Missions and Vehicle Concepts for Modern, Propelled, Lighter-than-Air Vehicles
1985-02-01
to he well-suited to airship capabilities, The third reason is the recent proposal of many new and innovative airship concepts, Finally, there is the...cases, have Initiated development of flight test and demonstration vehicles. It is the purpose of this volume to survey the results of these act vities...Several gas cells were arrayed longitudinally with the frame. These cells were free to expand and contract, thereby allowing for pressure and
Negotiating the Traffic: Can Cognitive Science Help Make Autonomous Vehicles a Reality?
Chater, Nick; Misyak, Jennifer; Watson, Derrick; Griffiths, Nathan; Mouzakitis, Alex
2018-02-01
To drive safely among human drivers, cyclists and pedestrians, autonomous vehicles will need to mimic, or ideally improve upon, humanlike driving. Yet, driving presents us with difficult problems of joint action: 'negotiating' with other users over shared road space. We argue that autonomous driving provides a test case for computational theories of social interaction, with fundamental implications for the development of autonomous vehicles. Copyright © 2017 Elsevier Ltd. All rights reserved.
Benefits of Using Remotely Operated Vehicles to Inspect USACE Navigation Structures
2007-03-01
ER D C/ CR R EL T R -0 7 -4 Benefits of Using Remotely Operated Vehicles to Inspect USACE Navigation Structures James H. Lever, Gary E...release; distribution is unlimited. ERDC/CRREL TR-07-4 March 2007 Benefits of Using Remotely Operated Vehicles to Inspect USACE Navigation...with inspections using divers or dewatering. In each case, benefits from reduced labor costs, shipping delays, and lost power production far exceed
Stigson, Helena; Krafft, Maria; Tingvall, Claes
2008-10-01
To evaluate if the Swedish Road Administration (SRA) model for a safe road transport system, which includes the interaction between the road user, the vehicle, and the road, could be used to classify fatal car crashes according to some safety indicators. Also, to present a development of the model to better identify system weakness. Real-life crashes with a fatal outcome were classified according to the vehicle's safety rating by Euro NCAP (European Road Assessment Programme) and fitment of ESC (Electronic Stability Control). For each crash, the road was also classified according to EuroRAP (European Road Assessment Programme) criteria, and human behavior in terms of speeding, seat belt use, and driving under the influence of alcohol. Each crash was compared with the model criteria, to identify components that might have contributed to fatal outcome. All fatal crashes where a car occupant was killed that occurred in Sweden during 2004 were included: in all, 215 crashes with 248 fatalities. The data were collected from the in-depth fatal crash data of the Swedish Road Administration (SRA). It was possible to classify 93% of the fatal car crashes according to the SRA model. A number of shortcomings in the criteria were identified since the model did not address rear-end or animal collisions or collisions with stationary/parked vehicles or trailers (18 out of 248 cases). Using the further developed model, it was possible to identify that most of the crashes occurred when two or all three components interacted (in 85 of the total 230 cases). Noncompliance with safety criteria for the road user, the vehicle, and the road led to fatal outcome in 43, 27, and 75 cases, respectively. The SRA model was found to be useful for classifying fatal crashes but needs to be further developed to identify how the components interact and thereby identify weaknesses in the road traffic system. This developed model might be a tool to systematically identify which of the components are linked to fatal outcome. In the presented study, fatal outcomes were mostly related to an interaction between the three components: the road, the vehicle, and the road user. Of the three components, the road was the one that was most often linked to a fatal outcome.
Improvement of Automated POST Case Success Rate Using Support Vector Machines
NASA Technical Reports Server (NTRS)
Zwack, Matthew R.; Dees, Patrick D.
2017-01-01
During early conceptual design of complex systems, concept down selection can have a large impact upon program life-cycle cost. Therefore, any concepts selected during early design will inherently commit program costs and affect the overall probability of program success. For this reason it is important to consider as large a design space as possible in order to better inform the down selection process. For conceptual design of launch vehicles, trajectory analysis and optimization often presents the largest obstacle to evaluating large trade spaces. This is due to the sensitivity of the trajectory discipline to changes in all other aspects of the vehicle design. Small deltas in the performance of other subsystems can result in relatively large fluctuations in the ascent trajectory because the solution space is non-linear and multi-modal [1]. In order to help capture large design spaces for new launch vehicles, the authors have performed previous work seeking to automate the execution of the industry standard tool, Program to Optimize Simulated Trajectories (POST). This work initially focused on implementation of analyst heuristics to enable closure of cases in an automated fashion, with the goal of applying the concepts of design of experiments (DOE) and surrogate modeling to enable near instantaneous throughput of vehicle cases [2]. Additional work was then completed to improve the DOE process by utilizing a graph theory based approach to connect similar design points [3]. The conclusion of the previous work illustrated the utility of the graph theory approach for completing a DOE through POST. However, this approach was still dependent upon the use of random repetitions to generate seed points for the graph. As noted in [3], only 8% of these random repetitions resulted in converged trajectories. This ultimately affects the ability of the random reps method to confidently approach the global optima for a given vehicle case in a reasonable amount of time. With only an 8% pass rate, tens or hundreds of thousands of reps may be needed to be confident that the best repetition is at least close to the global optima. However, typical design study time constraints require that fewer repetitions be attempted, sometimes resulting in seed points that have only a handful of successful completions. If a small number of successful repetitions are used to generate a seed point, the graph method may inherit some inaccuracies as it chains DOE cases from the non-global-optimal seed points. This creates inherent noise in the graph data, which can limit the accuracy of the resulting surrogate models. For this reason, the goal of this work is to improve the seed point generation method and ultimately the accuracy of the resulting POST surrogate model. The work focuses on increasing the case pass rate for seed point generation.
Development of a low-cost crash cushion using recycled automobile tires
DOT National Transportation Integrated Search
1998-09-01
Approximately 30 percent of all vehicle related fatalities that occur each year are caused by a single vehicle leaving the road and striking a fixed object; the most common objects struck being trees, guardrails, and utility poles. In many cases curr...
Overweight children: are they at increased risk for severe injury in motor vehicle collisions?
Zaveri, Pavan P; Morris, Danielle M; Freishtat, Robert J; Brown, Kathleen
2009-09-01
Obesity is an epidemic in the United States. The relationship between traumatic injury and obesity in children is not well-studied. We hypothesized that overweight children suffer more severe injuries, different distributions of injuries and improper use of restraints in motor vehicle collisions. We conducted a secondary analysis of the CIREN database of motor vehicle collisions of subjects 2-17 years old. Overweight was defined as a BMI percentile for age >85%. Significant injury was an Injury Severity Score (ISS) >15 or an Abbreviated Injury Scale (AIS) score greater than one. Further analysis looked at injuries classified as head, trunk, or extremities and appropriateness of restraints. Odds ratios compared the overweight to lean groups. 335 subjects met inclusion criteria with 35.5% of cases being overweight. For significant injury, overweight cases had an odds ratio of 1.2 [95% CI: 0.8-1.9]. Analysis by AIS for overall significant injury and to specific body regions also did not show any significant associations. Overweight versus lean subjects had an odds ratio of 1.3 [95% CI: 0.8-2.1] for improper use of restraints. We found no significant relationship between pediatric injury severity, distribution of injuries, or restraint use and being overweight. Limitations of this study were the small sample size in this database and the large number of unrestrained subjects.
NASA Technical Reports Server (NTRS)
Yang, Qi Rong
2014-01-01
Our current International Space Station Probabilistic Risk Assessment (ISS PRA) model assumes all collisions between a visiting vehicle (VV) and the ISS result in worst case loss of the ISS crew and the vehicle (LOCV). Drawing results from the Mir-Progress collision, we know this assumption is inaccurate because that collision did not lead to LOCV. Therefore the PRA team is conducting a study to determine the likelihood of LOCV when a collision occurs between a VV and the ISS. Kinetic energy is calculated and converted to pounds of TNT for the moving VVs when they collide with the ISS. Different scenarios are evaluated to obtain collision related data such as translational kinetic energy and rotational kinetic energy. These calculated data are integrated into the results from the expert elicitation performed on the Mir- Progress collision. As a result of this study, the PRA model will now calculate the probability of a VV collision with ISS, the probability that collision will result in Loss of Soyuz Crew (LOC) or Loss of ISS Crew and Vehicle (LOCV).
Kaca, Monika; Bock, Udo; Tawfik Jalal, Mohamed; Harms, Meike; Hoffmann, Christine; Müller-Goymann, Christel; Netzlaff, Frank; Schäfer, Ulrich; Lehr, Claus-Michael; Haltner-Ukomadu, Eleonore
2008-05-01
In order to prepare for a validation study to compare percutaneous absorption through reconstructed human epidermis with ex vivo skin absorption through human and animal skin, nine test compounds, covering a wide range of physicochemical properties were selected, namely: benzoic acid; caffeine; clotrimazole; digoxin; flufenamic acid; ivermectin; mannitol; nicotine; and testosterone. The donor and receptor media for the test substances, the addition of a solubiliser for the lipophilic compounds, as well as the stability and solubility of the test substances in the vehicles, were systematically analysed. Hydrophilic molecules, being freely soluble in water, were applied in buffered saline solutions. In order to overcome solubility restrictions for lipophilic compounds, the non-ionic surfactant, Igepal CA-630, was added to the donor vehicle, and, in the case of clotrimazole and ivermectin, also to the receptor fluid. The model molecules showed a suitable solubility and stability in the selected donor and receptor media throughout the whole duration of the test.
Laakso, Ilkka; Hirata, Akimasa
2013-11-07
In this study, an induced electric field in a human body is evaluated for the magnetic field leaked from a wireless power transfer system for charging an electrical vehicle. The magnetic field from the wireless power transfer system is modelled computationally, and its effectiveness is confirmed by comparison with the field measured in a previous study. The induced electric field in a human standing around the vehicle is smaller than the allowable limit prescribed in international guidelines, although the magnetic field strength in the human body is locally higher than the allowable external field strength. Correlation between the external magnetic field and the induced electric field is confirmed to be reasonable at least in the standing posture, which is the case discussed in the international standard. Based on this finding, we discussed and confirmed the applicability of a three-point magnetic field measurement at heights of 0.5, 1.0, and 1.5 m for safety compliance.
Plug-in hybrid electric vehicles as a source of distributed frequency regulation
NASA Astrophysics Data System (ADS)
Mullen, Sara Kathryn
The movement to transform the North American power grid into a smart grid may be accomplished by expanding integrated sensing, communications, and control technologies to include every part of the grid to the point of end-use. Plug-in hybrid electric vehicles (PHEV) provide an opportunity for small-scale distributed storage while they are plugged-in. With large numbers of PHEV and the communications and sensing associated with the smart grid, PHEV could provide ancillary services for the grid. Frequency regulation is an ideal service for PHEV because the duration of supply is short (order of minutes) and it is the highest priced ancillary service on the market offering greater financial returns for vehicle owners. Using Simulink a power system simulator modeling the IEEE 14 Bus System was combined with a model of PHEV charging and the controllers which facilitate vehicle-to-grid (V2G) regulation supply. The system includes a V2G controller for each vehicle which makes regulation supply decisions based on battery state, user preferences, and the recommended level of supply. A PHEV coordinator controller located higher in the system has access to reliable frequency measurements and can determine a suitable local automatic generation control (AGC) raise/lower signal for participating vehicles. A first step implementation of the V2G supply system where battery charging is modulated to provide regulation was developed. The system was simulated following a step change in loading using three scenarios: (1) Central generating units provide frequency regulation, (2) PHEV contribute to primary regulation analogous to generator speed governor control, and (3) PHEV contribute to primary and secondary regulation using an additional integral term in the PHEV control signal. In both cases the additional regulation provided by PHEV reduced the area control error (ACE) compared to the base case. Unique contributions resulting from this work include: (1) Studied PHEV energy systems and limitations on battery charging/discharging, (2) Reviewed standards for interconnection of distributed resources and electric vehicle charging [1], [2], (3) Explored strategies for distributed control of PHEV charging, (4) Developed controllers to accommodate PHEV regulation, and (5) Developed a simulator combining a power system model and PHEV/V2G components.
Characteristics and Outcomes of Out-of-Hospital Cardiac Arrest Occurring While in a Motor Vehicle.
Sado, Junya; Kiyohara, Kosuke; Hayashida, Sumito; Matsuyama, Tasuku; Katayama, Yusuke; Hirose, Tomoya; Kiguchi, Takeyuki; Nishiyama, Chika; Iwami, Taku; Kitamura, Yuri; Sobue, Tomotaka; Kitamura, Tetsuhisa
2018-06-01
This study aimed to investigate the incidence, patient characteristics, and outcomes of out-of-hospital cardiac arrest (OHCA) occurring while in a motor vehicle in Osaka City, Japan (with a population of 2.6 million), from 2009 to 2015. The OHCA data used in this study were obtained from the population-based Utstein-style registry in Osaka City. Patients who had OHCA occurring while in a motor vehicle were included. The primary end point was 1-month survival with favorable neurologic outcome after OHCA. During the study period, 18,458 OHCAs were observed, and 264 of them (1.4%) occurred while on or in a motor vehicle (drivers, n = 179; nondrivers, n = 85). The overall incidence rate of OHCAs occurring while in a motor vehicle was 14.0 per million population per year (drivers, 9.5; nondrivers, 4.5). In the drivers with OHCAs, 78 (43.6%) and 101 (56.4%) cases were of medical origin and traffic injuries, respectively. Approximately half of OHCAs with a medical origin in drivers presumably occurred while driving (46.2%, 36 of 78). The overall proportion of 1-month survival with favorable neurologic outcome after OHCA was 6.4% (17 of 264). In the drivers, the proportion of OHCAs with a medical origin and because of traffic injuries were 11.5% (9 of 78) and 2.0% (2 of 101) (p = 0.008), respectively. In conclusion, although OHCAs occurring while in a motor vehicle represented a small subset of the overall OHCA burden, a relatively large number of cardiac arrests with a medical origin occurred in drivers. Copyright © 2018 Elsevier Inc. All rights reserved.
Entry, Descent, and Landing technological barriers and crewed MARS vehicle performance analysis
NASA Astrophysics Data System (ADS)
Subrahmanyam, Prabhakar; Rasky, Daniel
2017-05-01
Mars has been explored historically only by robotic crafts, but a crewed mission encompasses several new engineering challenges - high ballistic coefficient entry, hypersonic decelerators, guided entry for reaching intended destinations within acceptable margins for error in the landing ellipse, and payload mass are all critical factors for evaluation. A comprehensive EDL parametric analysis has been conducted in support of a high mass landing architecture by evaluating three types of vehicles -70° Sphere Cone, Ellipsled and SpaceX hybrid architecture called Red Dragon as potential candidate options for crewed entry vehicles. Aerocapture at the Martian orbit of about 400 km and subsequent Entry-from-orbit scenarios were investigated at velocities of 6.75 km/s and 4 km/s respectively. A study on aerocapture corridor over a range of entry velocities (6-9 km/s) suggests that a hypersonic L/D of 0.3 is sufficient for a Martian aerocapture. Parametric studies conducted by varying aeroshell diameters from 10 m to 15 m for several entry masses up to 150 mt are summarized and results reveal that vehicles with entry masses in the range of about 40-80 mt are capable of delivering cargo with a mass on the order of 5-20 mt. For vehicles with an entry mass of 20 mt to 80 mt, probabilistic Monte Carlo analysis of 5000 cases for each vehicle were run to determine the final landing ellipse and to quantify the statistical uncertainties associated with the trajectory and attitude conditions during atmospheric entry. Strategies and current technological challenges for a human rated Entry, Descent, and Landing to the Martian surface are presented in this study.
Sun, Yingying; Huang, Zhibin; Zhao, Ziqin; Jiang, Yan; Ye, Yonghong; Yu, Tianfang; Rao, Yulan
2014-01-01
The purpose of our study was to better characterize and evaluate drunk driving for governmental reference in order to further reduce alcohol-impaired driving. This article reports the characteristics of 1226 alcohol-positive drivers with blood alcohol concentrations (BACs) at or over the legal limit of 0.20 mg/mL involved in nonfatal traffic accidents in Shanghai, China, from 2008 to 2011. The mean BAC, age, and gender of these drivers are discussed as well as the vehicle types and times of day when the crashes occurred. The mean BAC was 1.41 mg/mL and the mean age was 38 years old, and the vast majority of drivers were male (96.9%). The mean BAC of male drivers (1.42 mg/mL) was higher than that of female drivers (1.20 mg/mL). The mean age of male drivers (38) was also higher than that of female drivers (33). Distributions of vehicle types involved were studied. Cars had the highest percentage of occurrences (56.4%), followed by motorcycles (32.8%), electric bicycles (6.8%), trucks (1.5%), and bicycles (0.8%). It was found that these alcohol-related traffic crashes most often occurred between 7:00 p.m. and 10:59 p.m., representing 48.1 percent (n = 590) of the 1226 cases. Single-vehicle crashes were overrepresented (70.3%) in all cases. The mean BAC in multivehicle crashes (1.69 mg/mL) was higher than that in single-vehicle crashes (1.30 mg/mL). The results indicated a notable need for more governmental attention that would prevent accidents caused by driving under the influence of alcohol.
Occupational exposure assessment of highway toll station workers to vehicle engine exhaust.
Belloc-Santaliestra, Miriam; van der Haar, Rudolf; Molinero-Ruiz, Emilia
2015-01-01
Toll station workers are occupationally exposed to vehicle engine exhaust, a complex mixture of different chemical substances, including carcinogenic compounds. Therefore, a study was carried out on attendants of two highway toll stations to describe their occupational exposure to vehicle engine exhaust, based on a worst-case scenario approach. Personal sampling was conducted during the day shift for all attendants, testing for three groups of chemical substances: polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) and aldehydes (formaldehyde and acrolein). Concentrations of total PAH, BTEX (benzene, toluene, ethylbenzene, and xylenes) and formaldehyde content varied between 97.60-336.08 ng/m3, 5.01-40.52 μg/m3, and 0.06-19.13 μg/m3, respectively. No clear relationships could be established between exposure levels and the number of vehicles. Furthermore, no differences were found between truck versus car lanes, or inside versus outside the tollbooth. Not all the detected VOCs were related to vehicle exhaust; some were consistent with the use of cleaning products. The measured concentrations were far below the established occupational exposure limits, but tended to be higher than values reported for outdoor urban environments. There are very few international studies assessing occupational exposures among toll station workers, and this is the first such study to be conducted in Spain. The results suggest that further, more detailed studies are necessary to characterize exposure properly, and ones which include other airborne pollutants, such as ultrafine particles. The comparison of the results to other similar studies was difficult, since no data related to some important exposure determinants have been provided. Therefore, it is recommended that these determinants be considered in future studies.
NASA Technical Reports Server (NTRS)
Zwack, Mathew R.; Dees, Patrick D.; Holt, James B.
2016-01-01
Decisions made during early conceptual design have a large impact upon the expected life-cycle cost (LCC) of a new program. It is widely accepted that up to 80% of such cost is committed during these early design phases. Therefore, to help minimize LCC, decisions made during conceptual design must be based upon as much information as possible. To aid in the decision making for new launch vehicle programs, the Advanced Concepts Office (ACO) at NASA Marshall Space Flight Center (MSFC) provides rapid turnaround pre-phase A and phase A concept definition studies. The ACO team utilizes a proven set of tools to provide customers with a full vehicle mass breakdown to tertiary subsystems, preliminary structural sizing based upon worst-case flight loads, and trajectory optimization to quantify integrated vehicle performance for a given mission. Although the team provides rapid turnaround for single vehicle concepts, the scope of the trade space can be limited due to analyst availability and the manpower requirements for manual execution of the analysis tools. In order to enable exploration of a broader design space, the ACO team has implemented an advanced design methods (ADM) based approach. This approach applies the concepts of design of experiments (DOE) and surrogate modeling to more exhaustively explore the trade space and provide the customer with additional design information to inform decision making. This paper will first discuss the automation of the ACO tool set, which represents a majority of the development effort. In order to fit a surrogate model within tolerable error bounds a number of DOE cases are needed. This number will scale with the number of variable parameters desired and the complexity of the system's response to those variables. For all but the smallest design spaces, the number of cases required cannot be produced within an acceptable timeframe using a manual process. Therefore, automation of the tools was a key enabler for the successful application of an ADM approach to an ACO design study. Following the overview of the tool set automation, an example problem will be given to illustrate the implementation of the ADM approach. The example problem will first cover the inclusion of ground rules and assumptions (GR&A) for a study. The GR&A are very important to the study as they determine the constraints within which a trade study can be conducted. These trades must ultimately reconcile with the customer's desired output and any anticipated "what if" questions. The example problem will then illustrate the setup and execution of a DOE through the automated ACO tools. This process is accomplished more efficiently in this work by splitting the tools into two separate environments. The first environment encompasses the structural optimization and mass estimation tools, while the second is focused on trajectory optimization. Surrogate models are fit to the outputs of each environment and are "integrated" via connection of the surrogate equations. Throughout this process, checks are implemented to compare the output of the surrogates to the output of manually run cases to ensure that the error of the final surrogates is at an acceptable level. The conclusion of the example problem demonstrates the utility of the ADM based approach. Using surrogate models gives the ACO team the ability to visualize vehicle sensitivities to various design parameters and identify regions of interest within the design space. The ADM approach can thus be used to inform concept down selection and isolate promising vehicle configurations to be explored in more detail through the manual design process. In addition it provides the customer with an almost instantaneous turnaround on any ''what if" questions that may arise within the bounds of the surrogate model. This approach ultimately expands the ability of the ACO team to provide its customer with broad and rapid turnaround trade studies for launch vehicle conceptual design. The ability to identify a selection of designs which can meet the customer requirements will help ensure lower LCC of launch vehicle designs originating from ACO.
NASA Technical Reports Server (NTRS)
Zwack, Mathew R.; Dees, Patrick D.; Holt, James B.
2016-01-01
Decisions made during early conceptual design have a large impact upon the expected life-cycle cost (LCC) of a new program. It is widely accepted that up to 80% of such cost is committed during these early design phases.1 Therefore, to help minimize LCC, decisions made during conceptual design must be based upon as much information as possible. To aid in the decision making for new launch vehicle programs, the Advanced Concepts Office (ACO) at NASA Marshall Space Flight Center (MSFC) provides rapid turnaround pre-phase A and phase A concept definition studies. The ACO team utilizes a proven set of tools to provide customers with a full vehicle mass breakdown to tertiary subsystems, preliminary structural sizing based upon worst-case flight loads, and trajectory optimization to quantify integrated vehicle performance for a given mission.2 Although the team provides rapid turnaround for single vehicle concepts, the scope of the trade space can be limited due to analyst availability and the manpower requirements for manual execution of the analysis tools. In order to enable exploration of a broader design space, the ACO team has implemented an Advanced Design Methods (ADM) based approach. This approach applies the concepts of Design of Experiments (DOE) and surrogate modeling to more exhaustively explore the trade space and provide the customer with additional design information to inform decision making. This paper will first discuss the automation of the ACO tool set, which represents a majority of the development e ort. In order to t a surrogate model within tolerable error bounds a number of DOE cases are needed. This number will scale with the number of variable parameters desired and the complexity of the system's response to those variables. For all but the smallest design spaces, the number of cases required cannot be produced within an acceptable timeframe using a manual process. Therefore, automation of the tools was a key enabler for the successful application of an ADM approach to an ACO design study. Following the overview of the tool set automation, an example problem will be given to illustrate the implementation of the ADM approach. The example problem will first cover the inclusion of Ground Rules and Assumptions (GR&A) for a study. The GR&A are very important to the study as they determine the constraints within which a trade study can be conducted. These trades must ultimately reconcile with the customer's desired output and any anticipated \\what if" questions. The example problem will then illustrate the setup and execution of a DOE through the automated ACO tools. This process is accomplished more efficiently in this work by splitting the tools into two separate environments. The first environment encompasses the structural optimization and mass estimation tools, while the second is focused on trajectory optimization. Surrogate models are t to the outputs of each environment and are integrated via connection of the surrogate equations. Throughout this process, checks are implemented to compare the output of the surrogates to the output of manually run cases to ensure that the error of the final surrogates is at an acceptable level. The conclusion of the example problem demonstrates the utility of the ADM based approach. Using surrogate models gives the ACO team the ability to visualize vehicle sensitivities to various design parameters and identify regions of interest within the design space. The ADM approach can thus be used to inform concept down selection and isolate promising vehicle configurations to be explored in more detail through the manual design process. In addition it provides the customer with an almost instantaneous turnaround on any \\what if" questions that may arise within the bounds of the surrogate model. This approach ultimately expands the ability of the ACO team to provide its customer with broad and rapid turnaround trade studies for launch vehicle conceptual design. The ability to identify a selection of designs which can meet the customer requirements will have the potential to lower LCC of launch vehicle designs originating from ACO.