1. A seat cushion, comprising:
an open cell foam cushion for passenger comfort; and
a plurality of closed cell foam pieces distributed within the open cell foam cushion for flotation and structural support, the seat cushion including a greater density of the plurality of closed cell foam pieces adjacent the bottom of the cushion than adjacent the top of the cushion.
2. The seat cushion according to claim 1, wherein the plurality of closed cell foam pieces are spaced apart within the open cell foam cushion.
3. The seat cushion according to claim 1, wherein each of the plurality of closed cell foam pieces ranges in size from about 0.0015 cm3 to about 20 cm3.
4. The seat cushion according to claim 1, wherein the plurality of closed cell foam pieces collectively comprise from about 5 to 50% of the total volume of the seat cushion.
5. The seat cushion according to claim 1, wherein each of the plurality of closed cell foam pieces has substantially the same shape.
6. The seat cushion according to claim 1, wherein at least some of the plurality of closed cell foam pieces have different shapes.
7. The seat cushion according to claim 1, wherein each of the plurality of closed cell foam pieces has a donut shape.
8. The seat cushion according to claim 1, wherein each of the plurality of closed cell foam pieces is shaped like one of a donut, a sphere, a cylinder, a coil, a star shaped mace, a bent tube or a cage sphere.
9. The seat cushion according to claim 1, wherein the open cell foam cushion is constructed from polyurethane and the plurality of closed cell foam pieces are constructed from polyethylene.
10. An aircraft seat cushion, comprising:
a soft foam cushion for providing comfort for a passenger; and
a plurality of closed cell foam pieces distributed within the soft foam cushion for flotation and structural support;
wherein the aircraft seat cushion has greater compressibility near a top of the cushion than near a bottom of the cushion.
11. The aircraft seat cushion according to claim 10, wherein the plurality of closed cell foam pieces are spaced apart and substantially evenly distributed within the soft foam cushion.
12. The aircraft seat cushion according to claim 10, wherein the aircraft seat cushion includes a greater density of the plurality of closed cell foam pieces adjacent a bottom of the cushion than it does adjacent a top of the cushion.
13. The aircraft seat cushion according to claim 10, wherein each of the plurality of closed cell foam pieces range in size from about 0.0015 cm3 to about 20 cm3.
14. The aircraft seat cushion according to claim 10, wherein the soft foam cushion is constructed from open cell foam.
15. The aircraft seat cushion according to claim 10, wherein the plurality of closed cell foam pieces collectively comprise from about 5 to 50% of the total volume of the aircraft seat cushion.
16. The aircraft seat cushion according to claim 10, wherein each of the plurality of closed cell foam pieces has substantially the same shape.
17. The aircraft seat cushion according to claim 10, wherein each of the plurality of closed cell foam pieces has a donut shape.
18. The aircraft seat cushion according to claim 10, wherein each of the plurality of closed cell foam pieces is shaped like one of a donut, a sphere, a cylinder, a coil, a star shaped mace, a bent tube or a cage sphere.
19. The aircraft seat cushion according to claim 10, wherein the soft foam cushion is constructed from polyurethane and the plurality of closed cell foam pieces are constructed from polyethylene.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A computerized method for utilizing at least one state machine to solve a non-linear Boolean equation comprising:
partially solving said non-linear Boolean equation to determine at least one pre-computed search inference relating to said non-linear Boolean equation;
storing at least one precomputed search inference relating to said Boolean equation in said at least one state machine;
accessing said at least one search inference from said state machine to develop at least one heuristic for solving said non-linear Boolean equation;
iteratively searching for a solution to said equation by utilizing at least one heuristic developed from said at least one inference stored in said state machine.
2. A method as claimed in claim 1 wherein said non-linear Boolean equation is translated into a set of functions and wherein said functions are represented in a Binary Decision Diagram and further wherein said partial solving step comprises solving each function in said set of functions for all possible inputs.
3. A method as claimed in claim 1 further including the steps of computing a score for each of said at least one inference wherein said score is stored and associated with said at least one inference and wherein said score indicates a desirability of using said associated inference in said determining step.
4. A method as claimed in claim 3 wherein a set of heuristics is developed from said at least one inference in an order according to said score associated with said at least one inference.
5. A method as claimed in claim 1 wherein said state machine comprises at least one inference for a user domain relating to said non-linear Boolean equation.
6. A method as claimed in claim 5 wherein said state machine further comprises a computer readable data storage location for storing any linear inferences developed in said partial solving step.
7. A method as claimed in claim 1 wherein said state machine utilizes a technique selected from a group of autarkies, lemmas, andor pruning to reduce a set of inferences associated with a user domain associated with said non-linear Boolean function.
8. A computerized method for verifying that a circuit expression for a microprocessor matches a specification associated with said microprocessor comprising:
transforming said specification into a conjunction of logical expressions;
combining said conjunction with said circuit expression to produce a verification equation;
analyzing said verification equation via a Binary Decision Diagram;
partitioning said verification equation into a set of functions representing said verification equation;
processing each function in said set of functions for all possible inputs;
storing at least one inference developed from said processing step in a state machine;
iteratively searching for a solution to said equation by utilizing at least one heuristic developed from said at least one inference stored in said state machine.
9. A method as claimed in 8 wherein said searching step does not comprise translating said equation into Conjunctive Normal Format.
10. A computer system for solving a non-linear Boolean equation comprising a pre-processor, a state machine and a search engine wherein
A. said pre-processor is configured to perform the steps of
1. translating said Boolean equation into a set of functions;
2. solving said set of functions for all possible inputs;
B. said state machine is configured to store a set of at least one inferences developed from said solving step wherein said inferences are associated with a respective function in said set of functions;
C. a search engine configured to search for a solution to said Boolean equation using a set of heuristics developed from said set of inferences.