Abstract: A system to update a data structure based on a plurality of parent data structures, where at least one of the plurality of parent data structures is associated with point data. Some embodiments may include reception of a notification to update from one of the plurality of parent data structures, determination that one or more of the plurality of parent data structures is updating, determination of whether a notification to update has been received from each of the one or more of the plurality of parent data structures, and, if the notification to update has been received from each of the one or more of the plurality of parent data structures, update of the data structure based on data of the one or more of the plurality of parent data structures.

Abstract: A production stream analyzer, which analyzes a flowing crude oil production stream in a conduit, includes a temperature sensor, a capacitance measuring device and a densitometer which provide corresponding temperature, capacitance and density signals, respectively. An output circuit provides an output signal corresponding to the quantity of at least one constituent of the production stream in accordance with the temperature, the capacitance and the density signals.

Abstract: A method for fixedly positioned marine platform held at the ocean floor by piles and the like, having a relatively flat concrete apron disposed about the platform lower end and also supported on the ocean floor. The apron functions to stabilize the platform against lateral forces caused by water and wave motion, and also avoids scouring which would otherwise occur about the platform legs and piles due to movement of water along the ocean floor. The apron further lowers the center of gravity of the structure and improves its resistance to vibrations and resonance effects due to wave motion.

Abstract: A method for making transparent an underwater work area covered with cloudy water for servicing an offshore well and a subsurface well servicing and life supporting work chamber for practicing the method comprising a submarine chamber rotatably mounted on a base positioned centrally of a group of wells around the periphery of the base is disclosed. The chamber has a water filter and an ejection nozzle for ejecting clear water from the filter into an underwater cloudy area over a well to be serviced for providing a relatively transparent area of clear water to see through and work in.