1. A method for managing vapors generated by a first and second reservoir onboard a vehicle traveling on the road, the method comprising:
inducting vapors from the first and second reservoirs during engine operation;
reducing flow of vapors from the first reservoir to the second reservoir and from the second reservoir to the first reservoir, wherein said reducing includes restricting said flow of vapors from the first reservoir to the second reservoir and from the second reservoir to the first reservoir to prevent fuel vapors with different alcohol amounts from mixing; and
where the first reservoir contains ethanol.
2. The method of claim 1 wherein said first reservoir is coupled to a direct fuel injector.
3. The method of claim 1 wherein said second reservoir is coupled to a port fuel injector, said second reservoir containing gasoline.
4. The method of claim 1 wherein said first reservoir is coupled to a direct fuel injector, said first reservoir containing an alcohol; and wherein said second reservoir is coupled to a port fuel injector, said second reservoir containing gasoline.
5. The method of claim 1 wherein a check valve reduces flow of vapor from the first reservoir to the second reservoir.
6. The method of claim 1 wherein a canister reduces flow of vapor from the first reservoir to the second reservoir.
7. The method of claim 1 further comprising adjusting a valve coupled to the engine intake manifold to vary an amount of vapors from both reservoirs to the engine intake manifold.
8. The system of claim 1, wherein said first fuel reservoir has a smaller volume than said second fuel reservoir; and wherein said first vapor conduit is a smaller size than said second vapor conduit.
9. The system of claim 1, wherein said first fuel reservoir is coupled to a first direct injector of a cylinder of the engine; wherein said second fuel reservoir is coupled to one of a port injector and a second direct injector of the cylinder; wherein said first fuel includes an alcohol and said second fuel includes gasoline; and wherein said engine includes a boosting device.
10. The system of claim 1, further comprising a second one-way check valve disposed intermediate said second vapor conduit.
11. The system of claim 1, wherein said first canister is coupled to said first vapor conduit; and further comprising a second canister coupled to said second vapor conduit, wherein said second canister has a different characteristic than said first canister.
12. A system for an engine of a vehicle traveling on the road, comprising:
a first fuel reservoir configured to store a first fuel, said first fuel reservoir having a first vapor conduit configured to transport purge vapor from the first fuel reservoir;
a second fuel reservoir configured to store a second fuel different from said first fuel, said second fuel reservoir having a second vapor conduit configured to transport purge vapor from the second fuel reservoir;
a first one-way check valve disposed intermediate said first vapor conduit;
a first canister coupled to one of said first vapor conduit and said second vapor conduit;
a boosting device coupled to the engine; and
a first fuel vapor purge valve coupled to an intake manifold of the engine configured to vary an amount of purge vapors inducted into the intake manifold from one of said first fuel reservoir and said second fuel reservoir in response to operating conditions;
wherein said first one-way check valve is configured to permit purge vapor to flow from the first fuel reservoir and to restrict the flow of purge vapor into the first reservoir from the second reservoir, and wherein the first fuel includes one of an alcohol and gasoline; and wherein the second fuel includes another of said alcohol and gasoline.
13. The system of claim 12, wherein said first fuel vapor purge valve varies the amount of purge vapors inducted into the intake manifold from said first fuel reservoir; and further comprising a second fuel vapor purge valve coupled to the intake manifold of the engine configured to vary an amount of purge vapors inducted into the intake manifold in response to operating conditions from said second fuel reservoir.
14. A method for managing vapors generated by a first and second reservoir onboard a vehicle traveling on the road, the method comprising:
inducting vapors from the first and second reservoirs during engine operation;
reducing flow of vapors from the first reservoir to the second reservoir and from the second reservoir to the first reservoir, wherein said reducing includes restricting said flow of vapors from the first reservoir to the second reservoir and from the second reservoir to the first reservoir to prevent fuel vapors with different alcohol amounts from mixing; and
wherein said first reservoir is coupled to a direct fuel injector, said first reservoir containing an alcohol.
15. The method of claim 14 wherein said second reservoir is coupled to a port fuel injector, said second reservoir containing gasoline.
16. The method of claim 14 wherein a check valve reduces flow of vapor from the first reservoir to the second reservoir.
17. The method of claim 14 wherein a canister reduces flow of vapor from the first reservoir to the second reservoir.
18. The method of claim 14 further comprising adjusting a valve coupled to the engine intake manifold to vary an amount of vapors from both reservoirs to the engine intake manifold.
19. The method of claim 14 where said first reservoir contains ethanol.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method of encoding an input bit stream into a stream of output code words according to variable-length encoding rules using a variable constraint length, wherein a maximum value N of the constraint length is equal to or greater than 2, and the output-code-word stream observes prescribed run length limiting rules RLL (d, k), d and k denoting a predetermined minimum run length and a predetermined maximum run length respectively, the method comprising the steps of:
preparing M encoding tables in accordance with the variable-length encoding rules, M denoting a predetermined natural number equal to or greater than 2;
periodically inserting a DSV control bit into a first input bit stream at intervals each corresponding to a prescribed number of successive bits in the first input bit stream to change the first input bit stream into a second input bit stream;
encoding every m-bit piece of the second input bit stream into an n-bit output signal forming at least a portion of an output code word by referring to the M encoding tables, thereby converting the second input bit stream into a first output bit stream composed of output code words and observing the prescribed run length limiting rules RLL (d, k), m and n denoting predetermined natural numbers respectively;
inserting a sync word of a predetermined bit pattern into the first output bit stream for every frame to change the first output bit stream into a second output bit stream;
terminating a frame-end output code word at a position before a next-frame sync word; and
implementing DSV control of the second output bit stream in response to the inserted DSV control bits.
2. A method as recited in claim 1, wherein the M encoding tables register input bit patterns corresponding to the m-bit piece of the second input bit stream, n-bit output signals assigned to the input bit patterns respectively, and next-table selection numbers accompanying the n-bit output signals respectively and each designating one among the M encoding tables which will be used next; wherein the encoding step comprises encoding every m-bit piece of the second input bit stream into an n-bit output signal by referring to one of the M encoding tables which is designated by a current-table selection number being a next-table selection number provided by preceding encoding, and reading a next-table selection number accompanying the n-bit output signal from the designated one of the M encoding tables; and wherein the enabling step comprises using a termination table which registers at least one input bit pattern corresponding to the m-bit piece of the second input bit stream, at least one n-bit output signal assigned to the input bit pattern, and at least one next-table selection number accompanying the n-bit output signal and designating one among the M encoding tables which will be used next.
3. A method as recited in claim 1, wherein the numbers d and k are equal to 1 and 7, respectively.
4. An apparatus for encoding an input bit stream into a stream of output code words according to variable-length encoding rules using a variable constraint length, wherein a maximum value N of the constraint length is equal to or greater than 2, and the output-code-word stream observes prescribed run length limiting rules RLL (d, k), d and k denoting a predetermined minimum run length and a predetermined maximum run length respectively, the apparatus comprising:
M encoding tables accorded with the variable-length encoding rules, M denoting a predetermined natural number equal to or greater than 2, the M encoding tables registering input bit patterns corresponding to an m-bit piece of an input bit stream, n-bit output signals assigned to the input bit patterns respectively, and next-table selection numbers accompanying the n-bit output signals respectively and each designating one among the M encoding tables which will be used next;
means for periodically inserting a DSV control bit into a first input bit stream at intervals each corresponding to a prescribed number of successive bits in the first input bit stream to change the first input bit stream into a second input bit stream;
means for encoding every m-bit piece of the second input bit stream into an n-bit output signal forming at least a portion of an output code word by referring to one of the M encoding tables which is designated by a current-table selection number being a next-table selection number provided by preceding encoding, and reading a next-table selection number accompanying the n-bit output signal from the designated one of the M encoding tables, thereby converting the second input bit stream into a first output bit stream composed of output code words and observing the prescribed run length limiting rules RLL (d, k), m and n denoting predetermined natural numbers respectively;
means for inserting a sync word of a predetermined bit pattern into the first output bit stream for every frame to change the first output bit stream into a second output bit stream;
means for terminating a frame-end output code word at a position before a next-frame sync word; and
means for implementing DSV control of the second output bit stream in response to the inserted DSV control bits.
5. An apparatus as recited in claim 4, wherein the numbers d and k are equal to 1 and 7, respectively.
6. A recording medium storing a second output bit stream generated from a first input bit stream by the method of claim 1.
7. A method as recited in claim 2, wherein the numbers d and k are equal to 1 and 7, respectively.
8. A recording medium storing a second output bit stream generated from a first input bit stream by the method of claim 2.