Abstract: A process for determining the speed of a moving sport ball using a mobile device having a camera, the process comprising: providing instructions to a user on how to position the mobile device relative to a sport court of a known layout and in relation to which the sport ball is expected to move; providing feedback to the user about the position of the mobile device; determining the position of the mobile device relative to the sport court; video shooting of the moving sport ball using the camera of the mobile device; analyzing the video of the moving sport ball and extracting from the video the data necessary for computing the speed of the moving sport ball; computing the speed of the moving sport ball; and, displaying the computed speed on the screen of the mobile device.

Abstract: A process for determining the speed of a moving sport ball using a mobile device having a camera, the process comprising: providing instructions to a user on how to position the mobile device relative to a sport court of a known layout and in relation to which the sport ball is expected to move; providing feedback to the user about the position of the mobile device; determining the position of the mobile device relative to the sport court; video shooting of the moving sport ball using the camera of the mobile device; analyzing the video of the moving sport ball and extracting from the video the data necessary for computing the speed of the moving sport ball; computing the speed of the moving sport ball; and, displaying the computed speed on the screen of the mobile device.

Abstract: A fluid flow passage defined by a surface which surrounds the passage is provided with a plurality of projections, such as fibrils or brush like bristles, on the surface extending transversely to the flow passage. The projections serve to counteract or dampen the generation of high frequency sound energy or noise. The flow passage may be part of a medical or dental aspirator or industrial vacuum intake system or high pressure steam or gas exhaust system.

Abstract: The disclosure is directed to a vacuum aperture isolator for retroreflection of a laser-irradiated target. Within a vacuum chamber are disposed a beam focusing element, a disc having an aperture and a recollimating element. The edge of the focused beam impinges on the edge of the aperture to produce a plasma which refracts any retroreflected light from the laser's target.