Collision speed

When relaxation of the internal motion during the collision is fast compared with the slow collision speed v, or when the relaxation time is short compared with the collision time, the kinetic energy operator... 

Figure 4 Orbital distribution of classical and resonant KBOs. The numbers at top are ratios of the orbital periods (time to complete an orbit) of the objects to the orbital period of Neptune. The objects clustered around the 3 2 resonance are Plutinos swept up by the outward migration of Neptune. The large range of orbital inclinations produces in relative collision speeds comparable to the orbital speed ( 4 km s ) (source Luu and Jewitt, 2002).

The scenarios give important information about the critical situation and the constellation of the participants before the accident. In order to design measures of active safety, more detailed information about the scenarios is needed. Possible parameters of interest include, e.g., the time of day, initial speed of the vehicle, and collision speed of the vehicle. It is important to analyze every additional parameter not for all accidents, but per scenario individually. Regarding the time of day, it is daylight... 

It is well established that collision speed is the most important predictor for injury severity [3-7]. However, for constructing probability models for advanced applications, several additional research questions arise ... 

The second research question refers to the number of variables included in the models. As stated above, impact speed is the most important predictor for injury severity and mortality. However, it is known, for example, that fatality risk can be predicted more precisely using pedestrian age in addition to impact speed [6]. Thus, considering the spectrum of variables coded in the databases, it is important to identify potential explanatory variables beyond impact speed that could improve the predictive accuracy of the models. Possible explanatory variables include vehicle kinematics (e.g., collision speed), vehicle characteristics (e.g., height of the front bumper), and pedestrian physiology (e.g., age). 

If the collision speed equals zero Vc = Okph), the injury probability is defined as zero (p = 0). 

The univariate results Ifom the PCDS data set are summarized in Tables 5.7, 5.8 and 5.9 for ISS and in Table 5.10 for fatalities. The overriding importance of impact speed (vc pcDs) is also obvious in the PCDS data set. The unadjusted odds ratios associated with vehicle collision speed are between 8.098 and 17.225 and refer to a hypothetical increase in collision speed equal to the scaling factor (28.9 kph). 

Increasing the number of collisions speeds up the reaction rate. The more reactant molecules there are colliding, the faster the reaction will be. For example, a wood splint bums okay in air (20 percent oxygen), but it burns much faster in pure oxygen. 

The third dimension is the human measure. Here the approach is the same as that in Australia and the Netherlands the human being is liable to error and the human body can only absorb forces and accelerations/decelerations to a limited extent. Concerning this aspect, it is explicitly stated that the amount of energy in crashes must be limited through the reduction of driving speeds and collision speeds. 

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