| Word |
Description |
| Parks |
For more information on our Centurion Parks Software, or to download a current copy Centurion Parks |
| Pedestrian-Actuated Controller Assembly |
A controller assembly in which intervals, such as pedestrian WALK and clearance intervals, can be added to or included in the controller cycle by the actuation of a pedestrian detector (NEMA). Pedestrian actuation may be part of an intersection controller or be used to control a mid-block crosswalk.
See Also: Traffic-Actuated Controller Assembly, Semi-Traffic-Actuated Controller, and/or Full-Traffic-Actuated Controller Assembly |
| Pegasus |
Pegasus |
| Phoenix II |
Phoenix II Product |
| Piezo Sensor or Disk |
A piezoelectric disk generates a voltage when deformed (change in shape is greatly exaggerated) |
| Piezo-electric |
Piezoelectricity is the ability of some materials (notably crystals and certain ceramics, including bone) to generate an electric field or electric potential[1] in response to applied mechanical stress. The effect is closely related to a change of polarization density within the material's volume. If the material is not short-circuited, the applied stress induces a voltage across the material. The word is derived from the Greek piezo or piezein, which means to squeeze or press.
The piezoelectric effect is reversible in that materials exhibiting the direct piezoelectric effect (the production of an electric potential when stress is applied) also exhibit the reverse piezoelectric effect (the production of stress and/or strain when an electric field is applied). For example, lead zirconate titanate crystals will exhibit a maximum shape change of about 0.1% of the original dimension.
The effect finds useful applications such as the production and detection of sound, generation of high voltages, electronic frequency generation, micro-balances, and ultra fine focusing of optical assemblies.
It is also the basis of a number of scientific instrumental techniques with atomic resolution, the scanning probe microscopes such as STM, AFM, MTA, SNOM etc, and everyday uses such as acting as the ignition source for cigarette lighters and push-start propane barbecues. |
| PMS |
Pavement Management System |
| Pneumatics |
Pneumatics is the use of pressurized gas to effect mechanical motion.
Pneumatics is that branch of technology,which deals with the study and application of use of pressurized gas to affect mechanical motion.
Pneumatic power is used in industry, where factory machines are commonly plumbed for compressed air; other compressed inert gases can also be used. Pneumatics also has applications in dentistry, construction, mining, and other areas. |
| Presence Loop Detector |
An induction loop detector which is capable of detecting the presence of a standing or moving vehicle in any portion of ht effective loop area. |
| PSR |
Present Serviceability Rating |
| PTR |
Permanent Traffic Recorder (aka ATR) |
