Driving Conditions Research Articles

Motor Vehicle-Related Cardiac and Aortic Injuries Differ From Other Thoracic Injuries

Traumatic cardiac and thoracic aortic injuries are hypothesized to result from rapid deceleration of occupants during a motor vehicle crash. The purpose of this study was to identify potential risk factors for motor vehicle-related cardiac and thoracic aortic (HTA) injury using the Crash Injury Research Engineering Network (CIREN) database. CIREN data were used to test the hypothesis that there is no difference between occupants with HTA injury and occupants with thoracic injury other than the heart or aorta (non-HTA). Occupant variables (restraint use, airbag deployment, Glasgow Coma Scale score, Injury Severity Score, concomitant injuries, driver versus passenger status, height, and comorbidity) and crash variables (principal direction of force, change in velocity, vehicle crush, intrusion, and vehicle type) were compared for these two groups. Odds ratios were used to quantify the potential risk factors for HTA injury compared with non-HTA injury. There were 168 occupants with an HTA injury and 731 with a non-HTA injury. Greater crash severity (based on vehicle crush and change in velocity), improper safety belt use, and lack of safety belt use were significantly associated with HTA injury. Unrestrained occupants had almost three times the chance of having an HTA injury (odds ratio = 2.86; p < 0.05). For restrained drivers, 41.4% of HTA injuries were caused by vehicle interior components. When not protected by both safety belts and air bags, 45.7% of driver HTA injuries were caused by the steering wheel. For passengers, the vehicle interior (armrests, side interior, and B-pillars) accounted for most HTA injuries regardless of safety system status. More than half of all occupants wearing safety belts who sustained an HTA injury were improperly wearing their safety belts. The high mortality associated with cardiac and aortic injuries supports the need to prevent these injuries from occurring during motor vehicle crashes. These results suggest proper use of safety belts is necessary to prevent cardiac and thoracic aortic injuries. However, other important potential risk factors, such as motor vehicle size and crash severity, might continue to present a challenge to motor vehicle safety professionals.

0222 シート接触圧を用いたドライバ挙動抽出手法の検討(J17-1 交通機械のダイナミクス(1),J17 交通機械のダイナミクス)

This paper describes extraction method of driver behavior by using pressure distribution of the seat. Recently, a system which can monitor a car driver's biological condition and behavior is being proposed. In addition, new driver assist systems which are based on driver's biological condition and behavior are studying. Now, pressure of the driver's sheet has been noticed as one of the methods of measuring driver's biological conditions. The relation between step change of the pedal operation and the pressure distribution of the seat is investigated. The result of this study revealed that the driver's pedal stepping substitution behavior has been extracted from the seat contact pressure.

The effect of age, gender and driver status on pedestrians’ intentions to cross the road in risky situations

The theory of planned behaviour (TPB) has been used successfully in the past to account for pedestrians’ intentions to cross the road in risky situations. However, accident statistics show age and gender differences in the likelihood of adult pedestrian accidents. This study extends earlier work by examining the relative importance of the model components as predictors of intention to cross for four different adult age groups, men, women, drivers and nondrivers. The groups did not differ in the extent to which they differentiated between two situations of varying perceived risk. The model fit was good, but accounted for less of the variance in intention for the youngest group (17–24) than for other age groups. Differences between the age groups in intention to cross seemed to be due to differences in perceived value of crossing rather than differences in perceived risk. Women were less likely to intend to cross than men and perceived more risk, and there were important age, gender and driver status differences in the importance of the TPB variables as predictors of intention. A key implication of these findings is that road safety interventions need to be designed differently for different groups.

Upper extremity fracture patterns following motor vehicle crashes differ for drivers and passengers

Injury patterns of occupants in motor vehicle crashes are changing, with upper extremity injury becoming more common in patients treated at trauma centres. Although not life threatening, upper extremity injuries may result in long-term disability, including chronic deformity, neurovascular compromise and degenerative arthritis. The purpose of this study was to compare upper extremity injury in drivers and passengers using the Crash Injury Research Engineering Network (CIREN) database. CIREN data were used to compare upper extremity skeletal injury patterns and sources for drivers and passengers in frontal and side impacts. Occupant variables (age, gender, co-morbidity, avoidance maneuvers and restraint use) and crash variables (direction of impact, delta V and vehicle crush) were considered in the analysis. Only 24.8% of all occupants in the CIREN database had upper extremity injuries. One-half of upper extremity injuries to drivers were forearm fractures compared to one-third for passengers. Occupants in side impacts were more likely (OR=5.05) to have clavicle fractures, even while controlling for driver versus passenger status and safety belt use. Air bags were more likely to be a source of forearm fracture (OR=2.31) when controlling for driver versus passenger status, direction of force, sex and age compared to other sources. Only 10% of driver fractures with air bag deployment in frontal impacts were associated with air bag fling. This study found that drivers and passengers have different upper extremity injury patterns but the direction of impact also plays an important role.

Magnetostrictive bilayers for multi-functional sensor families

The present paper summarizes the development of new types of soft magnetic materials which are highly sensitive to bending or temperature, respectively. They represent bilayer structures, the thickness ranging from a few micrometers up to about 300 μm. A thin magnetostrictive layer is combined with a non-magnetic counter layer which counter-balances mechanical stress. As a result, bending generates stress of constant sign within the magnetic layer, thus, strongly enhancing its change of permeability. The bending sensitivity can be adjusted by several design parameters like layer thickness and Young's modulus. Temperature sensitivity can be attained through different expansion coefficients. First sensor prototypes were focused on automotive fields like flow measurement and driver status monitoring. A second focus was monitoring of physiological quantities during sleep, or after accidents. A large variety of parameters can be detected by means of one and the same sensor concept, which represents the main attraction of the novel concept.

512 腰部からの生体信号のセンシングに関する研究(S10-3 衝突安全と生体工学(2),S10 衝突安全と生体工学)

Recently, a system which can monitor a car driver's biological condition and warn the driver of drowsiness is being proposed. Many researchers have presented evidence that biological signals like brain waves, pulsation waves, and cardiac beat, are different between a wakeful state and a sleep state. However, current systems to measure those signals are assumed to be used in a laboratory or with invasive monitoring. We report on an Air-pressure sensor which is a noninvasive, biological signal-gathering sensor which goes on the car seat. It can measure body signal through the buttocks using a pulse wave-measuring instrument and a strain-type respiration-measuring device.

Development of driver's Status Monitor and Warning Presentation Method of Driver Support System

To develop a human-friendly driver support system, it is essential to detect the driver's status such as consciousness levels and looking aside. We have developed a driver monitoring system, which detect the driver's consciousness reduction and gaze direction change by image processing techniques. Furthermore, we have proposed a new warning method with this driver monitoring system. The effectiveness in this method has been verified using a driving simulator.

Development of a Driver-monitoring Vehicle Based on an Ultra Small Electric Vehicle

From the viewpoint of aging society in Japan, there is a need for vehicles adaptable for the elderly. Author et al. have developed an ultra small electric vehicle, which has a driver assist system suitable for elderly drivers. This system can take into account the various profiles among the elderly drivers, by monitoring the status of the driver and changing the vehicle response by means of by-wire technology. Driver-monitoring vehicle was developed based on this ultra small electric vehicle. This vehicle was equipped with measuring instruments, which monitors many aspect of driver's status. It was designed to monitor driver's operations and vital reactions in sync with vehicle conditions to find out the way to support drivers. In order to verify the function of the driver-monitoring vehicle, EMG measurements were taken. Effective measuring points of EMG were the tibialis anterior for braking and the deltoid muscle for steering. In the driving experiment, EMG rise occurred 0.5 second before driver's operation was implemented. And the feasibility of support system using EMG was indicated.

Development of driver's status monitor system by motion picture processing and measuring blinks from its use

Development of driver's status monitor system by motion picture processing and measuring blinks from its use

A multidimensional mixed ordered-response model for analyzing weekend activity participation

The objective of this paper is to examine the frequency of participation of individuals in out-of-home non-work and non-school episodes over the weekend. A multivariate mixed ordered response formulation accommodating the effects of explanatory variables and capturing the dependence among the propensity to participate in different activity types is presented and applied using a San Francisco Bay area travel survey conducted in 2000. The results indicate the important effects of household sociodemographics (income, household structure, and bicycle ownership), individual sociodemographics (age, employment status, gender, and availability of driver's license), internet use, location effects, and day of week/seasonal effects. Interestingly, the results show that motorized vehicle ownership and urban form characteristics of the individual's neighborhood (land-use mix and density) do not have a statistically significant effect on stop-making propensity for any of the activity purposes. The lack of effects of these variables may be due to self-selection of individuals and households into neighborhoods based on their travel preferences. That is, individuals and households may locate themselves based on their motorized vehicle ownership preferences and mobility preferences. In addition to the effect of several variables on stop-making, the model also reveals substitution and complementarity effects among different activity types due to unobserved factors.

Sleep-related fatal vehicle accidents: characteristics of decisions made by multidisciplinary investigation teams.

To analyze factors that explain the attribution of crash causes as sleep-related by accident investigators. Analysis of national database of fatal road accidents studied in depth. All nonprofessional nonintoxicated car drivers responsible for a fatal accident from 1991 to 2001 were included (N = 1464). Finland, with approximately 5.1 million inhabitants and 2.3 million motor vehicles. N/A. N/A. Comprehensive database recorded by multidisciplinary investigation teams, with specific emphasis on the availability of sleep-related driver variables and sleep-related causal decisions by teams. Injury severity, age, and marital status of the responsible car driver were related to the proportion of missing data in fatigue-related variables in the database (sleeping time, time awake, lifetime mileage). While there were differences between investigation teams and their activities, a series of logistic regression models showed that the lack of relevant variables in the database did not affect the proportion of accidents attributed to falling asleep (10% of cases) or as having fatigue-related causal factors (an additional 5% of the cases). The accident type (head-on and running-off versus other) and road conditions (dry or wet versus icy or snowy pavement) predicted the investigation teams' attribution of sleep-related causes in all models. Multidisciplinary teams' attribution of sleep-related causal factors were rather stable, comprising 10% to 15% of the cases investigated, independent of the availability of specific sleep-related information.

Driver's Status Monitor : Estimation of the driver's awareness and attention

Driver's Status Monitor : Estimation of the driver's awareness and attention

ドライバ状態に応じた警報提示(ヒューマンセンタードITS)

ドライバ状態に応じた警報提示(ヒューマンセンタードITS)

ドライバの状態検知,監視2 : まばたき計測による意識低下の検出(ヒューマンセンタードITS)

ドライバの状態検知,監視2 : まばたき計測による意識低下の検出(ヒューマンセンタードITS)

ドライバの状態検知・監視1 : 脇見検知のための視線検出(ヒューマンセンタードITS)

ドライバの状態検知・監視1 : 脇見検知のための視線検出(ヒューマンセンタードITS)

Airbag contact in traffic accidents: DNA detection to determine the driver identity.

A total of 34 deployed driver and passenger airbags from altogether 20 vehicles after frontal collisions were investigated. In 80% of the airbags possible biological traces could be located with an alternative light source (ALS, Polilight) at a wavelength of 450-470 nm. These traces were swabbed, a part of them additionally cut and subjected to DNA analysis, which led to comparable SGMplus profiles in about 60%. In the 20% of the airbags on which no possible biological traces could be located, the whole surfaces were swabbed. In these cases subsequent DNA profiling mostly led to non-interpretable results. For the evaluation and interpretation of the data, buccal swab samples provided by drivers and co-drivers were analysed. The results and conclusions from DNA analyses and the declarations from the involved passengers were always concordant. Thus, molecular biological analysis of deployed airbags can help to determine the occupants positions within a vehicle (driver or passenger status) at the time of impact.

Feasibility of Identification of Alcohol Intoxication by Nurses in Emergency Departments

Vehicle-related injuries are the major cause of death and injuries in Hualien County, and driving under the influence of alcohol plays a major role in such crashes. From December 1997 to May 1998, we determined the blood alcohol concentrations (BAC) of injured individuals from vehicle crashes at two emergency departments in Hualien. Nurses were asked to record whether the patient presented with an alcohol odor. The accuracy of detection by nurses was assessed from the BAC and groups with increased prevalence were identified for screening. Of 945 patients assessed, 505 (53.4%) tested positive by BAC and 320 (33.9%) were identified with an alcohol odor. With a BAC threshold of more than 50 mg/dL, detection sensitivity was 75.4%, specificity was 90.4%, and accuracy was 85.0% (95% confidence interval: 82.7, 87.3). Patients with an alcohol odor were significantly more likely to be men, aborigines, or head-injured patients. The accuracy of detection showed no significant difference by gender, head injury, or driver status. We suggest that detection of alcohol odor by nurses may be a feasible assessment of the role of alcohol in road traffic accidents. This may provide essential data for injury prevention strategies and programs.

Characteristics of pregnant women in motor vehicle crashes

Objectives: Motor vehicle crashes are the leading cause of hospitalized trauma during pregnancy. Maternal injury puts the fetus at great risk, yet little is known about the incidence, risks, and...

Transport safety for older people: A study of their experiences, perceptions and management needs

With evidence of increasing accident risk due to age-related declines in health and cognition affecting driver performance, there is a need for research promoting safe mobility of older people. The present study aimed to identify transport options and licensing issues for a group of older people in an Australian community. Ninety-five participants aged 75 and over were interviewed about their driving status and accident record and tested for cognitive ability. After stratification on cognitive level and driver status (current, ex-driver or non-driver), 30 were selected for further in-depth interviews concerning demographics, licence status and impact of change, travel options available and used, and travel characteristics. Considerable reliance on the motor vehicle as the mode of transport and the decision to cease driving were major quality-of-life issues. There was little evidence of planning and support in making the decision to stop driving. Some differences in transport decisions on the basis of cognitive level were evident; however, people with severely compromised cognitive ability (and, therefore, unable to give informed consent) had been excluded. The study suggested the need for resources to assist older people/carers/health professionals to plan for the transition from driver to non-driver and to manage alternative transport options more effectively.

Contracting in the Absence of Specific Investments and Moral Hazard: Understanding Carrier-Driver Relations in U.S. Trucking

This paper considers functions of contracting other than the protection of relationship-specific investments and the provision of marginal incentives, and applies the theory to explain variation in the form of compensation of over-the-road truck drivers in the U.S. Specifically, we argue that contracts in this industry serve to economize on the costs of price determination for heterogeneous transactions. We show that the actual terms of those contracts vary systematically with the nature of hauls in a way that is consistent with the theory. By contrast, we find that vehicle ownership, which defines a driver's status as an owner operator or company driver, depends on driver, but not trailer or haul, characteristics.