Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Design Consideration01:22

Design Consideration

681
Designing a structure involves a series of considerations, primarily the material's ultimate strength, calculated through tests that measure changes under increased force until the material reaches its breaking point or limit. The ultimate load, where the material breaks, is divided by its original cross-sectional area, resulting in the ultimate normal stress or strength. The ultimate shearing stress is another significant factor taken into account.
The factor of safety is another key...
681
Factors Affecting Creep01:28

Factors Affecting Creep

585
In normal-weight aggregate concrete, the hardened cement paste is the primary contributor to creep, whereas the aggregates, being stiffer than the cement paste, are more resilient to stress-induced deformation. The stiffness of the aggregates is defined by their modulus of elasticity, and the more voluminous they are in the concrete, the less it will creep.
Further, the water/cement ratio is critical, as a lower ratio increases concrete strength, thus reducing creep. The strength of the...
585
Elastic Collisions: Case Study01:15

Elastic Collisions: Case Study

17.1K
Elastic collision of a system demands conservation of both momentum and kinetic energy. To solve problems involving one-dimensional elastic collisions between two objects, the equations for conservation of momentum and conservation of internal kinetic energy can be used. For the two objects, the sum of momentum before the collision equals the total momentum after the collision. An elastic collision conserves internal kinetic energy, and so the sum of kinetic energies before the collision equals...
17.1K
Controller Configurations01:22

Controller Configurations

486
Controller configurations are crucial in a car's cruise control system because they manage speed over time to maintain a consistent pace regardless of road conditions, thereby meeting design goals. In traditional control systems, fixed-configuration design involves predetermined controller placement. System performance modifications are known as compensation.
Control-system compensation involves various configurations, most commonly series or cascade compensation, in which the controller...
486
Types of Impact01:30

Types of Impact

1.3K
Impacts can be classified in various forms, primarily under two subgroups: central impact and oblique impact. A central impact occurs when two objects collide head-on, possessing opposite velocities aligned along the line of impact. Conversely, an oblique impact occurs when two objects collide at an angle, resulting in a modification of both direction and velocity.
The coefficient of restitution is a metric for understanding the dynamics of impacts. It quantifies the ratio of relative velocity...
1.3K
Compacting Factor test01:22

Compacting Factor test

778
The compacting factor test is a method used to assess the workability of concrete. It is  especially suitable for concrete mixes containing aggregates up to one and a half inches in size. This test involves specialized equipment consisting of two truncated cone-shaped hoppers and a cylinder, all with polished interior surfaces to minimize friction.
The procedure begins by placing concrete into the upper hopper without any compaction. Once filled, the bottom door of this hopper is opened,...
778

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Transferring crash modification factors to automated vehicle environments using surrogate endpoints: Theoretical considerations.

Accident; analysis and prevention·2025
Same author

Mechanisms, mediators, and surrogate estimation of crash modification factors.

Accident; analysis and prevention·2021
Same author

Explaining crash modification factors: Why it's needed and how it might be done.

Accident; analysis and prevention·2019
Same author

Using naturalistic driving study data to investigate the impact of driver distraction on driver's brake reaction time in freeway rear-end events in car-following situation.

Journal of safety research·2017
Same author

Outline for a causal model of traffic conflicts and crashes.

Accident; analysis and prevention·2011
Same author

Collective responsibility for freeway rear-ending accidents? An application of probabilistic casual models.

Accident; analysis and prevention·2006

Related Experiment Video

Updated: May 6, 2026

Structural Design and Manufacturing of a Cruiser Class Solar Vehicle
14:57

Structural Design and Manufacturing of a Cruiser Class Solar Vehicle

Published on: January 30, 2019

14.7K

Crash reconstruction and crash modification factors.

Gary A Davis1

  • 1Dept. of Civil Engineering, University of Minnesota, 122 CivE, 500 Pillsbury Drive SE, Minneapolis, MN 55455, USA.

Accident; Analysis and Prevention
|November 12, 2013
PubMed
Summary

This study explores using reconstructed road crashes to estimate safety countermeasure effectiveness. It outlines conditions for simulation-based lower bounds and nonparametric estimation of crash modification factors.

Keywords:
Crash modification factorsCrash reconstructionCrash simulation

More Related Videos

A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
07:30

A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact

Published on: September 21, 2017

8.4K
Evaluation of an Exclusive Spur Dike U-Turn Design with Radar-Collected Data and Simulation
11:41

Evaluation of an Exclusive Spur Dike U-Turn Design with Radar-Collected Data and Simulation

Published on: February 1, 2020

18.1K

Related Experiment Videos

Last Updated: May 6, 2026

Structural Design and Manufacturing of a Cruiser Class Solar Vehicle
14:57

Structural Design and Manufacturing of a Cruiser Class Solar Vehicle

Published on: January 30, 2019

14.7K
A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
07:30

A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact

Published on: September 21, 2017

8.4K
Evaluation of an Exclusive Spur Dike U-Turn Design with Radar-Collected Data and Simulation
11:41

Evaluation of an Exclusive Spur Dike U-Turn Design with Radar-Collected Data and Simulation

Published on: February 1, 2020

18.1K

Area of Science:

  • Road safety
  • Causal inference
  • Traffic engineering

Background:

  • Estimating the effectiveness of safety countermeasures is crucial for road safety.
  • Reconstructed crash data offers a potential, yet complex, data source for such estimations.
  • Causal inference methods provide a framework for analyzing observational data in road safety.

Purpose of the Study:

  • To determine the conditions under which reconstructed road crash data can reliably estimate the impact of safety countermeasures.
  • To develop methods for estimating crash modification factors (CMFs) using reconstructed crash data.
  • To explore both simulation-based and nonparametric approaches for countermeasure effect estimation.

Main Methods:

  • Utilizing structural equation modeling and causal inference principles developed by Pearl and associates.
  • Implementing simulation techniques to assess countermeasure presence effects on reconstructed crashes.
  • Applying nonparametric estimation methods based on conditional independence and input distribution changes.

Main Results:

  • A lower bound for a crash modification factor can be estimated via simulation if structural equations and initiating conditions are identified.
  • This lower bound becomes a tight estimate if the countermeasure's effect is monotonic.
  • Nonparametric estimation of the crash modification factor is feasible when structural equations are not identifiable but conditional independence and input distribution shifts can be determined.

Conclusions:

  • Reconstructed road crashes can be valuable for estimating safety countermeasure effects under specific causal inference conditions.
  • Two distinct methodological pathways (simulation-based and nonparametric) are presented for estimating crash modification factors.
  • Even without full predictive power, identifying constraints for countermeasures can guide safety improvements.