Abstract: A modular system for the construction of pontoon boats includes a plurality of molded components that are assembled on the upper second surface to define the living space of the pontoon boat, wherein the molded components are secured to the upper surface of the pontoon boat. The plurality of molded components includes a roto core corner seating member, a roto core long side seating member, a roto core short side seating member, and a roto core helm member.

Abstract: Systems which utilize a series of managers to handle resource management. Three types of managers are preferably used, with each manager being in one of two states, active or available. The types of managers are Global Interface Manager (GIM), Resource Manager (RM) and Access Manager (AM). Associated with each device driver for a given function is a GIM. The device driver may be associated with one or more RMs and/or AMs. Among managers of a given type, one is the active manager and all other managers of that specific type are available and work with the active manager to handle resource requests. As there can be RMs for different resources, the active manager concept is applied to the RMs associated with each resource. Mechanisms are present to allow the active manager and related information to be transferred to an available manager if necessary.

Abstract: A method and system for use with object oriented databases provides schema evolution with deferred propagation of schema changes. The method and system provide a schema that persistently maintains class objects by storing an initial class definition, and shape objects associated with particular class objects and storing subsequent class definitions. The shape objects associated with a particular class object form a shape chain, the last shape object in the shape chain being the current shape object, and maintaining the current class definition. Client objects representing actual instances of data in the database, are instantiated from whichever client object or shape object is current at the time of instantiation, so the all newly created client objects always have the current class definition.

Abstract: A rotary spray nozzle directional tank cleaning machine has a first, stationary housing, a second housing mounted to the first housing for rotation about a first, typically vertical axis, and a third housing mounted to the second housing for rotation about a second axis. The second axis is at a first, acute angle to the first axis. The second housing is driven about the first housing through an impeller driven gear train by the pressurized cleaning liquid passing therethrough. The third housing is driven by a pair of bevel gears mounted to the first and third housings. One or more nozzles, mounted to the third housing, direct cleaning liquid along a third axis oriented at a second, acute angle to the second axis. The first and second, acute angles are preferably 45.degree. to create a hemispherical spray pattern.