Applying data mining techniques for technology prediction in new energy vehicle: a case study in China.

Technology prediction is an important technique to help new energy vehicle (NEV) firms keep market advantage and sustainable development. Under fierce competition in the new energy industry, there is an urgent necessity for innovative technology prediction method to effectively identify core and frontier technologies for NEV firms. Among the various methods of technology prediction, one of the most frequently used methods is to make technology prediction from patent data. This paper synthesizes the frequent pattern growth (FP-growth) algorithm and input-output analysis to construct a new technology prediction method based on the knowledge flow perspective, takes the data of NEV patent family in 1989-2018 the Derwent patent database as a sample, divides the data according to the 5-year standard, and uses the method to identify the core and frontier technologies in the NEV field during different periods. Furthermore, the multiple co-occurrence method applies to analyze the technology layout and evolution patterns in China's NEV field. The results show that the technology prediction method proposed in this paper can effectively identify core and frontier technologies to achieve NEV technology prediction.

Comprehensive safety assessment in mixed fleets with connected and automated vehicles: A crash severity and rate evaluation of conventional vehicles.

Connected and Automated Vehicle (CAV) technology, although in the development stage, is quickly expanding throughout the vehicle market. However, full market penetration will most likely require considerable planning as key stakeholders, manufacturers, consumers and governing agencies work together to determine optimal deployment strategies. Specifically, road safety is a critical challenge to the widespread deployment and adoption of this disruptive technology. During the transition period fleets will be composed of a combination of CAVs and conventional vehicles, and therefore it is imperative to investigate the repercussions of CAVs on traffic safety at different penetration rates. Since crash severity and frequency in conjunction reflect traffic safety, this study attempts to investigate the effect of CAVs on both crash severity and frequency through a microsimulation modelling exercise. VISSM microsimulation platform is used to simulate a case study of the M1 Geelong Ring Road network (Princes Freeway) in Victoria, Australia. Network performance is evaluated using performance metrics (Total System Travel Time, Delay) and kinematic variables (Speed, acceleration, jerk rate). Surrogate safety measures (time to collision, post encroachment time, etc.) are examined to inspect the safety in the network. The results indicate that the introduction of CAVs does not achieve the expected decrease in crash severity and rates involving manual vehicles, despite the improvement in network performance, given the demand and the set of parameters used in our operational CAV algorithm are intact. Additionally, the study identifies that the safety benefits of CAVs are not proportional to CAV penetration, and full-scale benefits of CAVs can only be achieved at 100 % CAV penetration. Further, considering network efficiency as a performance metric and total crash rate involving conventional vehicles as a safety metric, a Pareto frontier is extracted, for varying CAV operational behaviour. The results presented in this study provide insights into the impacts of CAVs on traffic safety valuable for insurance companies and other industry participants, enabling safety-related services and more enterprising business models.

Investigating the injury severity of single-vehicle truck crashes in a developing country.

Trucking plays a vital role in economic development in every country, especially countries where it serves as the backbone of the economy. The fast growth of economy in Iran as a developing country has also been accompanied by an alarming situation in terms of fatalities in truck-involved crashes, among the drivers and passengers of the trucks as well as the other vehicles involved. Despite the sizable efforts to investigate the truck-involved crashes, very little is known about the safety of truck movements in developing countries, and about the single-truck crashes worldwide. Thus, this study aims to uncover significant factors associated with injury severities sustained by truck drivers in single-vehicle truck crashes in Iran. The explanatory factors tested in the models include the characteristics of drivers, vehicles, and roadways. A random threshold random parameters hierarchical ordered probit model is utilized to consider heterogeneity across observations. Several variables turned out to be significant in the model, including driver's education, advanced braking system deployment, presence of curves on roadways, and high speed-limit. Using those results, we propose safety countermeasures in three categories of 1) educational, 2) technological, and 3) road engineering to mitigate the severity of single-vehicle truck crashes.

Identification of differential risk hotspots for collision and vehicle type in a directed linear network.

Traffic accidents can take place in very different ways and involve a substantially distinct number and types of vehicles. Thus, it is of interest to know which parts of a road structure present an overrepresentation of a specific type of traffic accident, specially for some typologies of collisions and vehicles that tend to trigger more severe consequences for the users being involved. In this study, a spatial approach is followed to estimate the risk that different types of collisions and vehicles present in the central area of Valencia (Spain), considering the accidents observed in this city during the period 2014-2017. A directed spatial linear network representing the non-pedestrian road structure of the area of interest was employed to guarantee an accurate analysis of the point pattern. A kernel density estimation technique was used to approximate the probability of risk along the network for each collision and vehicle type. A procedure based on these estimates and the sample size locally available within the network was designed and tested to determine a set of differential risk hotspots for each typology of accident considered. A Monte Carlo based simulation process was then defined to assess the statistical significance of each of the differential risk hotspots found, allowing the elaboration of rankings of importance and the possible rejection of the least significant ones.

Semi-autonomous vehicles: Usage-based data evidences of what could be expected from eliminating speed limit violations.

The use of advanced driver assistance systems and the transition towards semi-autonomous vehicles are expected to contribute to a lower frequency of motor accidents and to have a significant impact for the automobile insurance industry, as rating methods must be revised to ensure that risks are correctly measured. Telematics information and usage-based insurance research are analyzed to identify the effect of driving patterns on the risk of accident. This is used as a starting point for addressing risk quantification and safety for vehicles that can control speed. The effect of excess speed on the risk of accidents is estimated with a real telematics data set. Scenarios for a reduction of speed limit violations and the consequent decrease in the expected number of accident claims are shown. If excess speed could be eliminated, then the expected number of accident claims could be reduced to half of its initial value, applying the average conditions of the data used in this study. As a consequence, insurance premiums also diminish.

Assessment of the disaster medical response system through an investigation of a 43-vehicle mass collision on Jung-ang expressway.

PURPOSE: It was considered the challenges of the actual response and the potential for improvement, including the activities of the disaster response system, national emergency medical center, and the regional base hospital for the treatment of multiple traffic accident victims. The purpose of this study was to analyze the accident management system through real investigating the multiple collision over 10 vehicles with mass casualty events as a disaster situation. METHODS: This study was retrospective study to analyze the disaster event with multiple collision traffic accident on the expressway in Korea. We visited five medical centers for eight days since the accident occurred and interviewed the injured patients in this accident to examine the health status and medical records. After that, we visited the sixteen car-repair shops in four cities for real investigate about damaged vehicles. According to the arrangement of the accident situation for the accident vehicles through real-world investigation, we reproduced all parts of the accident scene, which were real-world investigated, by the accident situation sketch program. The collected data were summarized by Collision Deformation Classification (CDC) codes, and the medical records of the occupants were assessed using the Injury Severity Score (ISS). RESULTS: The cause of the accident was snow freezing of the road. The information about 72 injured patients on 31 damaged vehicles was collected by phone, visit, and actual accident investigation. Of the 72 patients who were examined, 4 were severely injured and 68 were mildly injured. The accident occurred in the order of Sedan 13 (41.9%), SUV 11 (35.5%), Truck 4 (12.9%), Van 2 (6.5%) and Bus 1 (3.2%). The median value of the age [lower quartile and upper quartile] was 43 [34.5-52] years old and the patients included 25 drivers, 11 passengers, 7 back seat passengers, and 29 bus passengers. CONCLUSION: The primary cause of this mass collision accident was road surface freezing, but the more serious secondary cause was a driver's inability to avoid the accident scene after the first collision. The severely injured occupants were occurred on the roads outside and inside the vehicle. In the event of a disaster, various teams from the police team, firefighting team, DMAT, EMS, road management team are gathered, and communication and command system between each team is important in order to identify and solve the disaster situation. To do this, it is important to develop manuals and prepare for training through repeated simulations.

Personal exposure and health risk assessment of carbonyls in family cars and public transports-a comparative study in Nanjing, China.

To evaluate passenger health risks associated with inhalation exposure to carbonyl compounds mainly emitted from decoration materials of vehicles, we tested the carbonyl concentrations in interior air of 20 family cars, 6 metro lines, and 5 buses in the city of Nanjing. To assess non-carcinogenic health risks, we compared the data to the health guidelines of China, US Environmental Protection Agency (EPA), and Office of Environmental Health Hazard Assessment (OEHHA), respectively. To assess carcinogenic risks, we followed a standard approach proposed by the OEHHA to calculate lifetime cancer risks (LCR) of formaldehyde and acetaldehyde for various age groups. The results showed that there are formaldehyde, acetaldehyde, and acrolein concentrations in 40, 35, and 50% of family car samples exceeded the reference concentrations (RfCs) provided by Chinese guidelines (GB/T 27630-2011 and GB/T 18883-2002). Whereas, in the tested public transports, concentrations of the three carbonyls were all below the Chinese RfCs. Fifty and 90% of family cars had formaldehyde and acrolein concentrations exceeding the guidelines of OEHHA. Only one public transport sample (one bus) possesses formaldehyde and acetaldehyde concentrations above the chronic inhalation reference exposure limits (RELs). Furthermore, the assessments of carcinogenic risk of formaldehyde and acetaldehyde showed that lifetime cancer risks were higher than the limits of EPA for some family cars and public transports. In the study, buses and metros appear to be relatively clean environments, with total carbonyl concentrations that do not exceed 126 µg/m3. In family cars, carbonyl levels showed significant variations from 6.1 to 811 µg/m3 that was greatly influenced by direct emissions from materials inside the vehicles. Public transports seemed to be the first choice for resident trips as compared to family cars. Graphical abstract ᅟ.

Investigating the real-world emission characteristics of light-duty gasoline vehicles and their relationship to local socioeconomic conditions in three communities in Los Angeles, California.

UNLABELLED: This paper discusses results from a vehicular emissions research study of over 350 vehicles conducted in three communities in Los Angeles, CA, in 2010 using vehicle chase measurements. The study explores the real-world emission behavior of light-duty gasoline vehicles, characterizes real-world super-emitters in the different regions, and investigates the relationship of on-road vehicle emissions with the socioeconomic status (SES) of the region. The study found that in comparison to a 2007 earlier study in a neighboring community, vehicle emissions for all measured pollutants had experienced a significant reduction over the years, with oxides of nitrogen (NOX) and black carbon (BC) emissions showing the largest reductions. Mean emission factors of the sampled vehicles in low-SES communities were roughly 2-3 times higher for NOX, BC, carbon monoxide, and ultrafine particles, and 4-11 times greater for fine particulate matter (PM2.5) than for vehicles in the high-SES neighborhood. Further analysis indicated that the emission factors of vehicles within a technology group were also higher in low-SES communities compared to similar vehicles in the high-SES community, suggesting that vehicle age alone did not explain the higher vehicular emission in low-SES communities. Evaluation of the emission factor distribution found that emissions from 12% of the sampled vehicles were greater than five times the mean from all of the sampled fleet, and these vehicles were consequently categorized as "real-world super-emitters." Low-SES communities had approximately twice as many super-emitters for most of the pollutants as compared to the high-SES community. Vehicle emissions calculated using model-year-specific average fuel consumption assumptions suggested that approximately 5% of the sampled vehicles accounted for nearly half of the total CO, PM2.5, and UFP emissions, and 15% of the vehicles were responsible for more than half of the total NOX and BC emissions from the vehicles sampled during the study. IMPLICATIONS: This study evaluated the real-world emission behavior and super-emitter distribution of light-duty gasoline vehicles in California, and investigated the relationship of on-road vehicle emissions with local socioeconomic conditions. The study observed a significant reduction in vehicle emissions for all measured pollutants when compared to an earlier study in Wilmington, CA, and found a higher prevalence of high-emitting vehicles in low-socioeconomic-status communities. As overall fleet emissions decrease from stringent vehicle emission regulations, a small fraction of the fleet may contribute to a disproportionate share of the overall on-road vehicle emissions. Therefore, this work will have important implications for improving air quality and public health, especially in low-SES communities.

Health impact assessment of transport policies in Rotterdam: Decrease of total traffic and increase of electric car use.

BACKGROUND: Green house gas (GHG) mitigation policies can be evaluated by showing their co-benefits to health. METHOD: Health Impact Assessment (HIA) was used to quantify co-benefits of GHG mitigation policies in Rotterdam. The effects of two separate interventions (10% reduction of private vehicle kilometers and a share of 50% electric-powered private vehicle kilometers) on particulate matter (PM2.5), elemental carbon (EC) and noise (engine noise and tyre noise) were assessed using Years of Life Lost (YLL) and Years Lived with Disability (YLD). The baseline was 2010 and the end of the assessment 2020. RESULTS: The intervention aimed at reducing traffic is associated with a decreased exposure to noise resulting in a reduction of 21 (confidence interval (CI): 11-129) YLDs due to annoyance and 35 (CI: 20-51) YLDs due to sleep disturbance for the population per year. The effects of 50% electric-powered car use are slightly higher with a reduction of 26 (CI: 13-116) and 41 (CI: 24-60) YLDs, respectively. The two interventions have marginal effects on air pollution, because already implemented traffic policies will reduce PM2.5 and EC by around 40% and 60% respectively, from 2010 to 2020. DISCUSSION: The evaluation of planned interventions, related to climate change policies, targeting only the transport sector can result in small co-benefits for health, if the analysis is limited to air pollution and noise. This urges to expand the analysis by including other impacts, e.g. physical activity and well-being, as a necessary step to better understanding consequences of interventions and carefully orienting resources useful to build knowledge to improve public health.

Estimating the burden of road traffic injuries among children and adolescents in urban South Asia.

Over a million people died from road traffic injuries (RTI) globally in the year 2000 and as many as 50 million were injured. Yet there has been little work focused on the South Asia region, let alone the vulnerable segments of population such as children and adolescents. This study aims at measuring the burden of disease caused by urban road traffic injuries among children and adolescents in South Asia. This study selected 26 studies for review and data extraction out of 1505 published articles. Data from the studies were pooled to calculate the proportion and characteristics of child and adolescent RTI, regional RTI incidence and mortality rates, and an estimate of the burden of disease caused by these injuries through the use of the healthy life years lost (HeaLY) composite measure. Our findings showed that the majority of injuries occurred in males (67-80%) and the most frequent age group injured was between ages 0 and 9 representing 40% of cases. Children and adolescents represent an average of 22% of all those with RTI whom seek care. Children and adolescents represented an average of 13% of all RTI deaths. Regional RTI incidence rate was calculated at 880 per 100,000 urban persons aged 0-19. Mortality due to RTI was at 17 deaths per 100,000 urban persons aged 0-19 in South Asia. Burden of disease was calculated 16 HeaLYs per 1000 general population from road traffic mortality alone. With disability data added, then 27.7 HeaLYs per 1000 general population are lost from road traffic injuries in South Asia. The increasing burden of RTI in young persons in South Asia is a call for considering appropriate research and effective interventions. This relatively high loss of healthy life from RTI needs to be addressed by public health systems in South Asia.

National road casualties and economic development.

OBJECTIVE: This paper explores why traffic fatalities increase with GDP per capita in lower income countries and decrease with GDP per capita in wealthy countries. METHODS: Data from 41 countries for the period 1992-1996 were obtained on road transport crashes, injuries, and fatalities as well as numbers of vehicles, kilometers of roadway, oil consumption, population, and GDP. Fixed effects regression was used to control for unobservable heterogeneity among countries. RESULTS: A 10% increase in GDP in a lower income country (GDP/Capita <1600) is expected to raise the number of crashes by 7.9%, the number of traffic injuries by 4.7%, and the number of deaths by 3.1% through a mechanism that is independent of population size, vehicle counts, oil use, and roadway availability. Increases in GDP in richer countries appear to reduce the number of traffic deaths, but do not reduce the number of crashes or injuries, all else equal. Greater petrol use and alcohol use are related to more traffic fatalities in rich countries, all else equal. CONCLUSION: In lower income countries a rise in traffic-related crashes, injuries, and deaths accompanies economic growth. At a threshold of around 1,500 dollars-8,000 dollars per capita economic growth no longer leads to additional traffic deaths, although crashes and traffic injuries continue to increase with growth. The negative association between GDP and traffic deaths in rich countries may be mediated by lower injury severity and post-injury ambulance transport and medical care.

Job change rate as a crash predictor for interstate truck drivers.

This research analyzed the Motor Carrier Management Information System (MCMIS) database to develop estimates of the increased risk of crash involvement experienced by commercial drivers who change jobs frequently. These analyses quantified the risk of single- and multiple-crash involvement as a function of annual job change rate, and expressed the relative risk for drivers with more versus fewer job changes through calculation of the "odds ratio" statistic. Significant odds ratio values were found, indicating that crash risk begins to rise when a driver has averaged more than two jobs with different employers each year for 2 years or longer, and that the odds of being involved in multiple crashes more than doubles for drivers with three or more jobs per year during this same interval. Opportunities for further research, focusing on variables that could be extracted from existing data sources to further enhance the validity and predictive value of the relationships found in this study, were also identified.

The relationship between perceived risk of being ticketed and self-reported seat belt use.

PROBLEM: Twenty-nine percent of Americans failed to use their seat belts in 2000. Efforts to improve safety belt usage can be enhanced by identifying specific factors that motivate belt use. METHOD: Motorist survey data were used to examine the effect of Perceived Risk of being Ticketed (PRT) for a seat belt infraction on self-reported seat belt use. RESULTS: Analyses indicated that individuals and groups of individuals who have higher PRT typically report higher belt usage. Factorial analyses indicated that this perceived risk to belt use relationship holds both within groups with generally high (e.g., upper income) and generally low (e.g. young men) overall self-reported belt use. DISCUSSION: Applications of PRT to improve seat belt use are discussed. IMPACT ON INDUSTRY: Enforcement of existing laws, perhaps through selective traffic enforcement programs, and strengthening laws to create a higher perception of being ticketed by motorists should increase safety belt use thereby saving lives and reducing cost for individuals, government, and industry.

Farmers' perceptions and concerns: the risks of driving farm vehicles on rural roadways in North Carolina.

This study focuses on farmers' perceptions of roadway safety and reviews specific and pertinent North Carolina rural road crash data to evaluate their perceptions and concerns. A survey was mailed to 1,357 prospective participants throughout North Carolina. Of these, 656 (48.3%) North Carolina farmers completed and returned the survey. The study revealed that while the majority of respondents took a number of specific safety measures to ensure their safety while driving their tractor on rural roads, most believed that driving their tractor on rural roads was more dangerous than it was five years ago. Few respondents believed that laws governing tractors on rural roads are well known by urban residents. While a majority of the respondents would support a law to mandate the use of a slow-moving vehicle (SMV) emblem on the back of slow-moving farm equipment, a majority also believed that a more effective way to mitigate potential crashes would be to ensure that all farm vehicles had blinking or flashing lights, that diamond-shaped caution signs depicting a tractor were posted on roadways with frequent tractor traffic, and that roadway shoulders were created or widened on roads with heavy farm traffic so that tractors could move off the roadway. Only 22% of respondents felt safe driving their tractor on rural roadways in North Carolina. Most respondents felt that the biggest problem with roadway safety was the lack of respect and increased speed of other drivers. Recent data indicate that in crashes involving farm vehicles, citations were issued to 34% of the non-farm vehicle operators and 24% to farm vehicle operators. For those driving non-farm vehicle who were deemed at fault, 66% were cited for failure to reduce speed. For those driving farm vehicles, the most frequent citation involved the lack of safe movement.