Abstract: In a process of detecting a person falling asleep, an image of the face of the person is acquired. Pixels of the image having characteristics corresponding to an eye of the person are selected and a histogram is formed of the selected pixels. The histogram is analyzed over time to identify each opening and closing of the eye, and characteristics indicative of the person falling asleep are determined. A sub-area of the image including the eye may be determined by identifying the head or a facial characteristic of the person, and then identifying the sub-area using an anthropomorphic model. To determine openings and closings of the eyes, histograms of shadowed pixels of the eye are analyzed to determine the width and height of the shadowing, or histograms of movement corresponding to blinking are analyzed.

Abstract: A plurality of inflation devices are linked to one another to form a loop that is movably restrained so that a segment of the loop is disposed at a lower reference location at the given depth in a first body of water, another segment of the loop is disposed at an upper reference location situated above the lower reference location, another segment of the loop extends along a first path that extends generally upward from the lower reference location to the upper reference location, and another segment of the loop extends along a second path that extends generally parallel to the first path and upward from the lower reference location to the upper reference location. At least a majority of the inflation devices occupying the first path are inflated with gas and at least a majority of the inflation devices occupying the second path are deflated so that inflation devices in the first path move upward and inflation devices in the second path move downward.