Abstract: An optical fiber coupled to a high power laser carries laser energy to la-activated sound generating materials disposed at intervals along its length. The sound-generating materials are acoustically coupled to an object or objects to be monitored. Acoustic reflections from the objects modulate the periods of Bragg gratings formed in a separate core of the fiber, or in the core of a separate fiber. The modulation of a Bragg grating period is detected as a Doppler shift in an interrogation beam reflected by the grating.

Abstract: A stake extractor device includes an elongated inner tube having a square cross-section and upper and lower ends, an elongated outer tube being shorter in length than the inner tube, the outer tube having a square cross-section and being fitted over the inner tube and slidable therealong between the upper and lower ends thereof, an upper stop element attached on the upper end of the inner tube so as to limit upward movement of the outer tube relative to the lower tube, a lower coupler element attached on the lower end of the inner tube so as to limit downward movement of the outer tube relative to the lower tube and being configured to receive a head portion of an object to be pulled, and handle members secured at inner ends to the outer tube next to an upper end thereof and extending in opposite directions from and in transverse relation to the outer tube. The handles are used for gripping by both hands of a user to move the outer tube relative to the inner tube in order to pull the object.

Abstract: A removable support apparatus for supporting a swimming pool cover employs adjustable frame assemblies capable of spanning between opposite edges at opposite sides of the pool. Each frame assembly includes a pair of separate frame members placed in side-by-side relation to one another so that together they define the overall length of the frame assembly. The frame members are displacable longitudinally relative to one another to adjust the overall length of the frame assembly to match the distance between the opposite edges of the pool so that the frame assembly can fit across the pool between its opposite edges. Each frame assembly also includes an end support member attached to the outer end of each frame member and supporting the frame member from one of the opposite edges of the pool.

Abstract: A crutch cast support or crutch leg support is provided by a loop of flexible material attached to a crutch at a location of the crutch that is closer to a shoulder support of the crutch than to a hand hold of the crutch, the loop of flexible material hanging loosely from a mounting mechanism that mounts the loop to the crutch. Preferably, the mounting mechanism provides three degrees of freedom where the loop is mounted to the crutch to enhance swinging motion of the loop in a walking direction with respect to the crutch, in a direction transverse to the walking direction, and in rotation about an axis disposed in a longitudinal direction of the crutch. The loop of flexible material is provided by a strap, the length of which is adjustable, so that a leg of a user may be supported at a wide variety of places including the area of the knee, a location closer to the ankle than to the knee, and from below the foot.