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- Jakobsson, Lotta, 1967, et al.
(author)
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Evaluation criteria for AIS 1 neck injuries in frontal impacts - A parameter study combining field data and Madymo modelling
- 2004
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In: Traffic Injury Prevention. - : Informa UK Limited. - 1538-957X .- 1538-9588. ; 5:4, s. 374-381
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Journal article (peer-reviewed)abstract
- Two situations with an expected higher AIS 1 neck injury rate in frontal impact were compared to a reference situation using a Madymo human body model in three different sitting postures and four different crash pulses. The two situations were reduced occupant weight and occupant with initial forward arm resistance, respectively. Occupant neck motion phases were identified and corresponding possible evaluation criteria were evaluated within the phases. Typical neck kinematics was seen for the two different situations. Occupants of lower weight had a more extended neck in the initial protraction phase and also a generally more pronounced upper neck link angle. Occupants with initial arm resistance had generally greater lower neck link angle at the time when the upper neck link angle was straight. No evaluation criteria reflected the anticipated AIS 1 neck injury rate consistently. In the initial protraction phase, NICmincorrelated to expected injury outcome in almost half of the cases. In the protractionflexion shift phase, Nkm, Nij, upper neck shear force and neck tension force reflected anticipated severity outcome to some extent. In the flexion phase, upper and lower neck extension correlated to anticipated AIS 1 neck injury rate only to a minor extent. The different sitting postures were more influential than the different crash pulses, emphasizing the importance of not only considering the spectra of impact severity but also differences in sitting postures in safety system development and evaluation.
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2. |
- Jakobsson, Lotta, 1967, et al.
(author)
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Parameters influencing AIS 1 neck injury outcome in frontal impacts
- 2004
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In: Traffic Injury Prevention. - : Informa UK Limited. - 1538-957X .- 1538-9588. ; 5:2, s. 156-63
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Journal article (peer-reviewed)abstract
- In order to gain more knowledge of the neck injury scenario in frontal impacts, a statistical study of parameters influencing incidences of AIS 1 neck injuries was performed. The data set consisted of 616 occupants in Volvo cars. Information regarding the crash, the safety systems, occupant characteristics (including prior neck problems), behavior and sitting posture at the time of impact, and neck symptoms (including duration) was collected and analyzed. Occupant characteristics (mainly gender, weight, and age), kinematics (head impacts) and behavior at the time of impact were identified as the most prominent parameter areas with regard to AIS 1 neck injury outcome. Specifically, women had a significantly higher AIS 1 neck injury rate as compared to men, occupants under the age of 50 had a significantly higher AIS 1 neck injury rate as compared to those above 50 and occupants weighing less than 65 kg have a significantly higher AIS 1 neck injury rate than heavier occupants. Drivers stating that they impacted their head against a frontal interior structure had a significantly higher AIS 1 neck injury rate than those without head impact. Also, occupants who stated they had tensed their neck muscles at the time of impact, had a significantly higher AIS 1 neck injury rate as compared to occupants who did not. Occupant activities, such as tightly gripping the steering wheel or straightening their arms showed a significantly increased AIS 1 neck injury rate, indicating that occupant behavior at time of impact could be influential with respect to AIS 1 neck injury outcome. Also, occupants reporting prior neck problems had a higher rate of persistent symptoms (>1 year) but no difference with respect to passing symptoms (
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3. |
- Morris, A, et al.
(author)
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The Development of a Multidisciplinary System to Understand Causal Factors in Road Crashes
- 2006
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In: 42nd Annual Human Factors and Ergonomics Society of Australia Conference 2006, HFESA 2006. - 9781622769599 ; , s. 31-38
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Conference paper (other academic/artistic)abstract
- The persistent lack of crash causation data to help inform and monitor road and vehicle safety policy is a major obstacle. Data are needed to assess the performance of road and vehicle safety stakeholders and is needed to support the development of further actions. A recent analysis conducted by the European Transport Safety Council identified that there was no single system in place that could meet all of the needs and that there were major gaps including in-depth crash causation information. This paper describes the process of developing a data collection and analysis system designed to fill these gaps. A project team with members from 7 countries was set up to devise appropriate variable lists to collect crash causation information under the following topic levels: accident, road environment, vehicle, and road user, using two quite different sets of resources: retrospective detailed police reports (n=1300) and prospective, independent, on-scene accident research investigations (n=1000). Data categorisation and human factors analysis methods based on Cognitive Reliability and Error Analysis Method (Hollnagel, 1998) were developed to enable the causal factors to be recorded, linked and understood. A harmonised, prospective "on-scene" method for recording the root causes and critical events of road crashes was developed. Where appropriate, this includes interviewing road users in collaboration with more routine accident investigation techniques. The typical level of detail recorded is a minimum of 150 variables for each accident. The project will enable multidisciplinary information on the circumstances of crashes to be interpreted to provide information on the causal factors. This has major applications in the areas of active safety systems, infrastructure and road safety, as well as for tailoring behavioural interventions. There is no direct model available internationally that uses such a systems based approach.
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4. |
- Tivesten, Emma, 1968, et al.
(author)
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Nonresponse analysis and adjustment in a mail survey on car accidents
- 2012
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In: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 48:Special Issue: SI, s. 401-415
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Journal article (peer-reviewed)abstract
- Statistical accident data plays an important role for traffic safety development involving the road system, vehicle design, and driver education. Vehicle manufacturers use data from accident mail surveys as an integral part of the product development process. Low response rates has, however, lead to concerns on whether estimates from a mail survey can be trusted as a source for making strategic decisions.The main objective of this paper was to investigate nonresponse bias in a mail survey addressing driver behaviour in accident situations. Insurance data, available for both respondents and nonrespondents were used to analyze, as well as adjust for nonresponse. Response propensity was investigated by using descriptive statistics and logistic regression analyses. The survey data was then weighted by using inverse propensity weights. Two specific examples of survey estimates are addressed, namely driver vigilance and driver's distraction just before the accident. The results from this paper reveal that driver age and accident type were the most influential variables for nonresponse weighting. Driver gender and size of town where the driver resides also had some influence, but not for all survey variables investigated.The main conclusion of this paper is that nonresponse weighting can increase confidence in accident data collected by a mail survey, especially when response rates are low. Weighting has a moderate influence on this survey, but a larger influence may be expected if applied on a more diverse driver population. The development of auxiliary data collection can further improve accident mail survey methodology in future.
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5. |
- Wågström, Linus, 1977, et al.
(author)
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A methodology for improving structural robustness in frontal car-to-car crash scenarios
- 2013
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In: International Journal of Crashworthiness. - : Informa UK Limited. - 1358-8265 .- 1754-2111. ; 18:4, s. 385-396
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Journal article (peer-reviewed)abstract
- There has been significant development in passenger car crashworthiness over the last few decades. However, real-world crashes often occur in scenarios dissimilar to laboratory barrier crash set-ups. Further knowledge is required on how different impact scenarios affect vehicle structural response and occupant injury risk in real-world scenarios. This study introduces a methodology for assessing crash configuration parameters that influence the structural response in car-to-car frontal collisions by using finite element models of two identical vehicles. The crash configuration parameters included in this study were initial velocities, oblique angle and lateral offset distance. An evaluation was made in terms of passenger compartment intrusion and crash pulse severity. Special focus was directed towards investigating whether these input parameters can be used to define incompatible scenarios, i.e. where the structural response in one vehicle is significantly different compared to the other vehicle. Results indicate that collision scenarios with large overlap as extreme in terms of crash pulse severity, and incompatible car-to-car crash scenarios were found at small overlap and an oblique angle of 15 degrees. An outlook for future model and method validation work is described.
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