Search results for "crash"

Distraction of cyclists: how does it influence their risky behaviors and traffic crashes?

2018

BackgroundUndisputedly, traffic crashes constitute a public health concern whose impact and importance have been increasing during the past few decades. Specifically, road safety data have systematically shown how cyclists are highly vulnerable to suffering traffic crashes and severe injuries derived from them. Furthermore, although the empirical evidence is still very limited in this regard, in addition to other human factors involved in cycling crashes, distractions while cycling appear to be a major contributor to the road risk of cyclists.ObjectivesThe main objectives of this study were, first, to explore the prevalence and trends of cycling distractions within an international sample o…

Design of a new high energy rear underrun protective device

2008

In recent years the vehicle design field has followed a progressive evolution by focusing its main interest on passive and active safety levels. One of the most injurious cases for the safety of passengers is the crash between a car and a heavy vehicle (truck). Generally, in fact, when such an occurrence happens, the greatest damage is suffered by the passengers of the car. This is because of the considerable structural difference between the two vehicles and the lack of devices to reduce the injuries of the car passengers. In this work, as a consequence of the previous considerations, we deal with the design of a new protective system for heavy vehicles over 3.5 tons. The new rear underrun…

Mathematical modeling of a vehicle crash test based on elasto-plastic unloading scenarios of spring-mass models

2011

Published version of an article in the journal: The International Journal of Advanced Manufacturing Technology. Also available from the publisher on SpringerLink: htp://dx.doi.org/10.1007/s00170-010-3056-x This paper investigates the usability of spring which exhibit nonlinear force-deflection characteristic in the area of mathematical modeling of vehicle crash. We present a method which allows us to obtain parameters of the spring-mass model basing on the full-scale experimental data analysis. Since vehicle collision is a dynamic event, it involves such phenomena as rebound and energy dissipation. Three different spring unloading scenarios (elastic, plastic, and elasto-plastic) are covered…

Investigation of vehicle crash modeling techniques: theory and application

2013

Published version of an article in the journal: The International Journal of Advanced Manufacturing Technology. Also available from the publisher at: http://dx.doi.org/10.1007/s00170-013-5320-3 Creating a mathematical model of a vehicle crash is a task which involves considerations and analysis of different areas which need to be addressed because of the mathematical complexity of a crash event representation. Therefore, to simplify the analysis and enhance the modeling process, in this work, a brief overview of different vehicle crash modeling methodologies is proposed. The acceleration of a colliding vehicle is measured in its center of gravity—this crash pulse contains detailed informati…

The performance investigation of viscoelastic hybrid models in vehicle crash event representation

2011

Aurthor's version of a chapter published in the book: Proceedings of the 18th IFAC World Congress 2011. Also available from the publisher at: http://dx.doi.org/10.3182/20110828-6-IT-1002.00284 This paper presents application of physical models composed of springs, dampers and masses joined together in various arrangements to simulation of a real car collision with a rigid pole. Equations of motion of those systems are being established and subsequently solutions to obtained differential equations are formulated. We start with a general model consisting of two masses, two springs, and two dampers, and illustrate its application to represent fore-frame and aft-frame of a vehicle. Hybrid model…

Reproduction of kinematics of cars involved in crash events using nonlinear autoregressive models

2012

Vehicle crashworthiness can be assessed by the variety of methods - the most common and direct one is a vehicle crash test. Visual inspection and obtained measurements, such as car acceleration, are used to examine impact severity of an occupant and overall car safety. However, those experiments are complex, time-consuming, and expensive. We propose a method to reproduce car kinematics during a collision using a feedforward neural network to estimate the system by use of nonlinear autoregressive (NAR) models. Specifically, feasibility of applying neural networks with an NAR model to the analysis of experimental data is explored by application to measurements of a vehicle crash test. This mo…

Effect of welding and heat treatment on the properties of UHSS used in automotive industry

2021

This paper deals with the undesired effects of the heat treatments on the mechanical properties of (UHSS) Ultra High Strength Steel used nowadays in automotive industry to improve crashworthiness performance of vehicles. The UHSS specimens were extracted from certain parts of the car body and subjected to different heat treatments. Four types of specimens were tested: untreated, welded with metal inert gas welding, heat treated at 800 °C, and heat treated at 1250 °C. All heat-treated specimens showed dramatically reduced values of strength. The results suggest that it is important to follow the official repair manuals avoiding unnecessary welding and improper heat treatments of UHSS. The ex…

On the (In)Security of 1090ES and UAT978 Mobile Cockpit Information Systems : An Attacker Perspective on the Availability of ADS-B Safety- and Missio…

2022

Automatic dependent surveillance-broadcast (ADS-B) is a key air surveillance technology and a critical component of next-generation air transportation systems. It significantly simplifies aircraft surveillance technology and improves airborne traffic situational awareness. Many types of mobile cockpit information systems (MCISs) are based on ADS-B technology. MCIS gives pilots the flight and traffic-related information they need. MCIS has two parts: an ADS-B transceiver and an electronic flight bag (EFB) application. The ADS-B transceivers transmit and receive the ADS-B radio signals while the EFB applications hosted on mobile phones display the data. Because they are cheap, lightweight, an…

Diabetic Kidney Disease and COVID-19: The Crash of Two Pandemics

2020

Hair cortisol predicts avoidance behavior and depressiveness after first-time and single-event trauma exposure in motor vehicle crash victims

2020

The role of cortisol as a premorbid vulnerability factor for trauma sequelae remains unclear. Furthermore, the onset of long-term endocrine changes in response to first-time trauma as a function of later psychopathology is not clarified yet. Thus the predictive value of pre- and post-traumatic hair cortisol concentrations (HCCs) for psychological trauma sequelae was investigated in response to motor vehicle crash (MVC). A total of