Two low-cost methods of estimating the road surface condition are presented in the paper, the first one
based on the use of accelerometers and the other on the analysis of images acquired from cameras installed
in a vehicle. In the first method, miniature positioning and accelerometer sensors are used for evaluation of
the road surface roughness. The device designed for installation in vehicles is composed of a GPS receiver
and a multi-axis accelerometer. The measurement data were collected from recorded ride sessions taken
place on diversified road surface roughness conditions and at varied vehicle speeds on each of examined
road sections. The data were gathered for various vehicle body types and afterwards successful attempts
were made in constructing the road surface classification employing the created algorithm. In turn, in the
video method, a set of algorithms processing images from a depth camera and RGB cameras were created.
A representative sample of the material to be analysed was obtained and a neural network model for classification
of road defects was trained. The research has shown high effectiveness of applying the digital image
processing to rejection of images of undamaged surface, exceeding 80%. Average effectiveness of identification
of road defects amounted to 70%. The paper presents the methods of collecting and processing the
data related to surface damage as well as the results of analyses and conclusions.
Inclined jet air cooling can be effectively used for cooling of electronics or other such applications. The non-confined air jet is impinged and experimentally investigated on the hot target surface to be cooled, which is placed horizontally. Analysis and evaluations are made by introduction of a jet on the leading edge and investigated for downhill side cooling to identify cold spots. The jet Reynolds number in the range of 2000 ≤ Re ≤ 20000 is examined with a circular jet for inclination (Ɵ) of 15 < Ɵ < 75 degree. Also, the consequence of a jet to target distance (H) is explored in the range 0.5 ≤ H/D ≤ 6.8. For 45 degree jet impingement, the maximum Nusselt number is widely spread. Location of maximum Nusselt number is studied, which indicates cold spots identification. At a higher angle ratio, the angle is the dominating parameter compared to the Reynolds Number. Whereas at a lower angle ratio, the inclined jet with a higher Reynolds number is giving the cooling point away from leading edge. It is observed that for a particular angle of incident location of maximum Nusselt Number, measured from leading edge of target, is ahead than that of stagnation point in stated conditions.
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