Abstract: A cooling system for cooling units of furniture adapted for supporting the human body, and for car seats, steering wheels and arm rests, includes two main components. A closed loop air conditioning subsystem has a first motor which drives a compressor in which a refrigerant fluid is compressed. The compressed fluid is passed into a condenser where the compressed fluid is cooled by dissipating its heat into the environment, and from where the compressed fluid is released through an expansion valve into an evaporator. The evaporator becomes cool due to expansion of the refrigerant fluid into a gas and consequent absorption of heat from the evaporator's body and immediate environment. The refrigerant gas is returned from the evaporator into the compressor.

Abstract: A personal watercraft, such as a jet ski, is equipped with a hull, an engine and propulsion and a ride plate assembly attached to the bottom section of the hull. The ride plate assembly includes a fixed plate and a lower plate or flap hingedly mounted to the fixed plate to occupy continuously adjustable varying angular positions relative to the fixed plate. A manually operated control mechanism, controlled by an operator, adjusts the angular positioning of the flap within a predetermined range. It is an important characteristic of the continuously adjustable flap that within the range in which its angular positioning relative to the fixed plate and to the water can be changed, an initial and moderate change in angular positioning results in more hydrodynamic lift to act on the watercraft, and therefore in increased speed of the watercraft. However, beyond a certain value, further deflection of the flap results in significant braking action.