1. A disk drive, comprising:
at least one disk including a plurality of tracks for storing data, wherein the plurality of tracks are divided into a plurality of zones including at least a first zone of tracks and a second zone of tracks adjacent the first zone;
a read element constructed to read data stored in the plurality of tracks;
a write element constructed to write data in the plurality of tracks;
a memory storing a plurality of write counters for the plurality of zones, with each write counter representing a number of times a zone of the plurality of zones has been completely written by the write element; and
a controller configured to:
retrieve a write counter for the first zone from the memory;
determine whether the write counter for the first zone exceeds a threshold value during a zone monitoring process, the zone monitoring process being performed to determine whether any of the plurality of write counters stored in the memory exceed the threshold value;
control the read element to read data stored in at least a portion of the second zone if it is determined that the write counter for the first zone exceeds the threshold value; and
control the write element to rewrite the data read by the read element from the second zone if it is determined that the write counter for the first zone exceeds the threshold value.
2. The disk drive of claim 1, wherein the controller is further configured to determine whether the write counter for the first zone exceeds the threshold value in response to a request to write data in the first zone.
3. The disk drive of claim 2, wherein the controller is further configured to:
control the write element to write data in accordance with the request to write data in the first zone if it is determined that the write counter for the first zone does not exceed the threshold value; and
increment the write counter for the first zone after the write element has written data in the first zone in accordance with the request to write data in the first zone.
4. The disk drive of claim 1, wherein the controller is further configured to control the write element to rewrite the data read by the read element from the second zone in a zone associated with a lowest write counter of the plurality of write counters stored in the memory.
5. The disk drive of claim 1, wherein the at least one disk includes a third zone of tracks adjacent the first zone and on a side of the first zone opposite the second zone, and wherein the controller is further configured to:
control the read element to read data stored in at least a portion of the third zone if it is determined that the write counter for the first zone exceeds the threshold value; and
control the write element to rewrite the data read by the read element from the third zone if it is determined that the write counter for the first zone exceeds the threshold value.
6. The disk drive of claim 1, wherein the controller is further configured to:
disable writing in the first zone until after the rewritten data of the second zone has been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
reset the write counter for the first zone after the rewritten data of the second zone has been rewritten.
7. The disk drive of claim 5, wherein the controller is further configured to:
disable writing in the first zone until after the rewritten data of the second and third zones have been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
reset the write counter for the first zone after the rewritten data of the second and third zones have been rewritten.
8. A method for managing data stored in a disk drive having at least one disk including a plurality of zones including at least a first zone of tracks for storing data and a second zone of tracks for storing data, wherein the second zone is adjacent the first zone, the method comprising:
determining whether a write counter for the first zone exceeds a threshold value during a zone monitoring process to determine whether any write counters of a plurality of write counters for the plurality of zones exceed the threshold value, with each write counter representing a number of times a zone of the plurality of zones has been completely written with data; and
controlling the disk drive to rewrite data from at least a portion of the second zone if it is determined that the write counter for the first zone exceeds the threshold value.
9. The method of claim 8, further comprising determining whether the write counter for the first zone exceeds the threshold value in response to a request to write data in the first zone.
10. The method of claim 9, further comprising:
controlling the disk drive to write data in accordance with the request to write data in the first zone if it is determined that the write counter for the first zone does not exceed the threshold value; and
incrementing the write counter for the first zone after data has been written in the first zone in accordance with the request to write data in the first zone.
11. The method of claim 8, wherein controlling the disk drive to rewrite data written in at least a portion of the second zone includes rewriting the data from the second zone in a zone associated with a lowest write counter of the plurality of write counters.
12. The method of claim 8, wherein the at least one disk includes a third zone of tracks adjacent the first zone and on a side of the first zone opposite the second zone, and wherein the method further comprises controlling the disk drive to rewrite data from at least a portion of the third zone if it is determined that the write counter for the first zone exceeds the threshold value.
13. The method of claim 8, further comprising:
disabling writing in the first zone until after the rewritten data of the second zone has been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
resetting the write counter for the first zone after the rewritten data of the second zone has been rewritten.
14. The method of claim 12, further comprising:
disabling writing in the first zone until after the rewritten data of the second and third zones have been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
resetting the write counter for the first zone after the rewritten data of the second and third zones have been rewritten.
15. A non-transitory computer readable medium storing computer-executable instructions for managing data stored in a disk drive having at least one disk including a plurality of zones including at least a first zone of tracks for storing data and a second zone of tracks for storing data, wherein the second zone is adjacent the first zone, and wherein when the computer-executable instructions are executed by a controller or a processor, the computer-executable instructions cause the controller or processor to:
determine whether a write counter for the first zone exceeds a threshold value during a zone monitoring process for determining whether any write counters of a plurality of write counters for the plurality of zones exceed the threshold value, with each write counter representing a number of times a zone of the plurality of zones has been completely written with data; and
control the disk drive to rewrite data from at least a portion of the second zone if it is determined that the write counter for the first zone exceeds the threshold value.
16. The non-transitory computer readable medium of claim 15, wherein the computer-executable instructions further cause the controller or the processor to determine whether the write counter for the first zone exceeds the threshold value is made in response to a request to write data in the first zone.
17. The non-transitory computer readable medium of claim 15, wherein the at least one disk includes a third zone of tracks adjacent the first zone on a side opposite the second zone, and wherein the computer-executable instructions further cause the controller or the processor to control the disk drive to rewrite data from at least a portion of the third zone if it is determined that the write counter for the first zone exceeds the threshold value.
18. A disk drive, comprising:
at least one disk including a plurality of tracks for storing data, wherein the plurality of tracks are divided into at least a first zone of tracks and a second zone of tracks adjacent the first zone;
a read element constructed to read data stored in the plurality of tracks;
a write element constructed to write data in the plurality of tracks;
a memory storing a write counter for the first zone, wherein the write counter represents a number of times the first zone has been completely written with data by the write element; and
a controller configured to:
retrieve the write counter for the first zone from the memory;
determine whether the write counter for the first zone exceeds a threshold value; and
if it is determined that the write counter for the first zone exceeds the threshold value:
control the read element to read data stored in at least a portion of the second zone;
control the write element to rewrite the data read by the read element from the second zone;
disable writing in the first zone until after the rewritten data of the second zone has been rewritten; and
reset the write counter for the first zone after the rewritten data of the second zone has been rewritten.
19. The disk drive of claim 18, wherein the controller determines whether the write counter for the first zone exceeds the threshold value in response to a request to write data in the first zone.
20. The disk drive of claim 19, wherein the controller is further configured to:
control the write element to write data in accordance with the request to write data in the first zone if it is determined that the write counter for the first zone does not exceed the threshold value; and
increment the write counter for the first zone after the write element has written data in the first zone in accordance with the request to write data in the first zone.
21. The disk drive of claim 18, wherein the memory stores a plurality of write counters for a plurality of zones of tracks, with each write counter representing a number of times a zone of the plurality of zones has been completely written by the write element, and wherein the controller is further configured to control the write element to rewrite the data read by the read element from the second zone in a zone associated with a lowest write counter of the plurality of write counters stored in the memory.
22. The disk drive of claim 18, wherein the at least one disk includes a third zone of tracks adjacent the first zone and on a side of the first zone opposite the second zone, and wherein the controller is further configured to:
control the read element to read data stored in at least a portion of the third zone if it is determined that the write counter for the first zone exceeds the threshold value; and
control the write element to rewrite the data read by the read element from the third zone if it is determined that the write counter for the first zone exceeds the threshold value.
23. The disk drive of claim 22, wherein the controller is further configured to:
disable writing in the first zone until after the rewritten data of the second and third zones have been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
reset the write counter for the first zone after the rewritten data of the second and third zones have been rewritten.
24. A method for managing data stored in a disk drive having at least one disk including a first zone of tracks for storing data and a second zone of tracks for storing data, wherein the second zone is adjacent the first zone, the method comprising:
determining whether a write counter for the first zone exceeds a threshold value, wherein the write counter for the first zone represents a number of times the first zone has been completely written with data; and
if it is determined that the write counter for the first zone exceeds the threshold value:
controlling the disk drive to rewrite data from at least a portion of the second zone;
disabling writing in the first zone until after the rewritten data of the second zone has been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
resetting the write counter for the first zone after the rewritten data of the second zone has been rewritten.
25. The method of claim 24, wherein the determination of whether the write counter for the first zone exceeds the threshold value is made in response to a request to write data in the first zone.
26. The method of claim 25, further comprising:
controlling the disk drive to write data in accordance with the request to write data in the first zone if it is determined that the write counter for the first zone does not exceed the threshold value; and
incrementing the write counter for the first zone after data has been written in the first zone in accordance with the request to write data in the first zone.
27. The method of claim 24, wherein controlling the disk drive to rewrite data written in at least a portion of the second zone includes rewriting the data from the second zone in a zone associated with a lowest write counter of a plurality of write counters for a plurality of zones of tracks with each write counter representing a number of times a zone of the plurality of zones has been completely written.
28. The method of claim 24, wherein the at least one disk includes a third zone of tracks adjacent the first zone and on a side of the first zone opposite the second zone, and wherein the method further comprises controlling the disk drive to rewrite data from at least a portion of the third zone if it is determined that the write counter for the first zone exceeds the threshold value.
29. The method of claim 28, further comprising:
disabling writing in the first zone until after the rewritten data of the second and third zones have been rewritten if it is determined that the write counter for the first zone exceeds the threshold value; and
resetting the write counter for the first zone after the rewritten data of the second and third zones have been rewritten.
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 fuel cell module comprising:
a first unit cell comprising a first electrode, an electrolyte layer and a second electrode; and
a second unit cell assembly connected to the first unit cell and comprising at least a second unit cell,
wherein respective fuel reaction areas of the unit cells of the fuel cell module are different from one another.
2. The fuel cell module according to claim 1, wherein the unit cells of the fuel cell module are connected such that the respective fuel reaction areas of the unit cells increase along a length of the fuel cell module.
3. The fuel cell module according to claim 1, wherein the unit cells of the fuel cell module are connected substantially along a direction in which fuel is supplied to the fuel cell module.
4. The fuel cell module according to claim 3, wherein the unit cells of the fuel cell module are connected such that respective lengths of the unit cells increase along the direction in which fuel is supplied, and wherein a rate of increase between the lengths of adjacent unit cells is less than or equal to 1.5.
5. The fuel cell module according to claim 4, wherein the respective lengths of the unit cells of the fuel cell module sequentially increase along the direction in which fuel is supplied.
6. The fuel cell module according to claim 5, wherein the first unit cell is provided with a fuel inlet through which fuel is supplied to the fuel cell module.
7. The fuel cell module according to claim 6, wherein one of the at least a second unit cell of the second unit cell assembly is provided with a fuel outlet through which fuel is discharged from the fuel cell module.
8. The fuel cell module according to claim 4, wherein the length of the first unit cell is about 10 to 20 cm.
9. The fuel cell module according to claim 8, wherein a sum of the respective lengths of the unit cells of the fuel cell module is about less than or equal to 50 cm.
10. The fuel cell module according to claim 1, wherein respective lengths of the unit cells of the fuel cell module are different from one another.
11. The fuel cell module according to claim 10, wherein the length of one of the unit cells of the fuel cell module varies by less than or equal to 50% with respect to the length of an adjacent unit cell.
12. The fuel cell module according to claim 11, wherein the first electrode is an anode and the second electrode is a cathode.
13. The fuel cell module according to claim 11, further comprising connection caps between the unit cells.
14. The fuel cell module according to claim 13, wherein a length of each of the connection caps is substantially the same.
15. The fuel cell module according to claim 13, further comprising at least one of Ni wires or Ag wires formed as current collectors on the first and second electrodes.
16. The fuel cell module according to claim 13, further comprising at least one of Pt wires or Ag wires formed as current collectors on the first and second electrodes.