1. A navigation apparatus for in-vehicle use, the apparatus comprising:
a processing resource operably coupled to a data store, the data store comprising data representing a digital map;
a location determination unit operably coupled to the processing resource and capable of determining a location;
a vehicle communications interface for communicating with an in-vehicle data system for carrying sensed information obtained from at least a steering position sensor for sensing an angular position of the vehicle steering control;
a server communications interface for communicating with a server; wherein the processing resource is configured to:
(i) receive via the vehicle communications interface, the sensed information indicating an angular position of steering;
(ii) selectively store, into the data store, information obtained from the sensed information, and the position of the vehicle corresponding to the occurrence of sensed information as determined by the location determining unit; and
(iii) selectively output the logged information to the server communications interface for uploading to a server for determining lane width.
2. The navigation apparatus of claim 1, wherein the processing resource is further operable to store information indicating vehicle speed corresponding to the occurrence of said sensed information.
3. The navigation apparatus of claim 2, wherein the vehicle speed is obtained, via the vehicle communications interface, from a speed sensor of the vehicle.
4. The navigation apparatus of claim 2, wherein the vehicle speed is obtained by calculation of the rate of change of position determined by the location determination unit.
5. The navigation apparatus of claim 1, wherein the navigation device is a portable navigation device, and wherein the vehicle communications interface is a wireless interface.
6. The navigation apparatus of claim 1, wherein the processing resource is configured to analyse the sensed steering position information, determine the occurrence of in-lane steering corrections, and store information defining each occurrence of an in-lane steering steering correction.
7. Apparatus for communicating with plural navigation devices that are usable in vehicles, the apparatus comprising:
a processing resource operably coupled to a data store, the data store comprising data representing digital map information for uploading to a navigation device;
a communications interface for communicating with navigation devices and configured for downloading information to the navigation devices and uploading information from the navigation devices;
wherein the processing resource is configured to:
receive from at least one navigation device stored information representative of steering of the vehicle while driving, and the corresponding vehicle position at the time of the steering; and
analyse said information statistically to determine therefrom an estimated lane width of the road used by the vehicle.
8. The apparatus of claim 7, wherein the stored information further comprises information representative of vehicle speed at the time of steering, and wherein the processing resource is configured to determine the lane width based on one or more of: the frequency of repetition of steering corresponding statistically to in-lane steering corrections, the amplitude of steering corresponding statistically to in-lane steering corrections, vehicle speed.
9. The apparatus of claim 7, wherein the processing resource is configured to receive said stored information as a stream of sampled data representing a continuous record of steering.
10. The apparatus of claim 7, wherein the processing resource is configured to receive said stored information as a sequence of information events, each event correspond to a change in vehicle steering.
11. The apparatus of claim 7, wherein the processing resource is further configured to combine statistically the information received from plural navigation devices.
12. A method of operation of a navigation device for in-vehicle use, the method comprising:
performing location determination to determine a location of the navigation device;
establishing communication between the navigation device and an in-vehicle data system for carrying sensed information obtained from at least a steering position sensor for sensing an angular position of the vehicle steering control;
receiving the sensed information indicating an angular position of steering;
selectively storing, during at least one vehicle journey, information obtained from the sensed information, and the position of the vehicle corresponding to the occurrence of sensed information as determined by the location determining step;
establishing communication between the navigation device and server apparatus; and
selectively outputting the stored information to the server for determining lane width using the outputted information.
13. A method of operation of apparatus for communicating with a plurality of navigation devices, the method comprising:
establishing communication with at least one of the plural navigation devices;
receiving from said at least one navigation device stored information representative of steering of the vehicle while driving, and the corresponding vehicle position at the time of the steering; and
analysing said information statistically to determine therefrom an estimated lane width of the road used by the vehicle.
14. The method of claim 13, wherein the step of analysing comprises analyzing information from plural navigation devices having information for at least one road in common.
15. A computer program element comprising computer program code, which when executed by a processor resource, causes the processor resource to implement a method as defined in claim 12.
16. A computer program element as claimed in claim 15, embodied on a computer readable medium.
17. A method of determining lane width of a road, the method comprising: providing a plurality of navigation devices for in-vehicle use, each navigation device being configured to store information obtained from a steering sensor of a respective vehicle representing steering of the vehicle while on the road;
receiving the stored information from the plurality of navigation devices; and
analyzing the received information statistically to determine, from the characteristics of in-lane steering corrections, a value of lane width for said road.
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 method for spanning a single file across a plurality of tape media in a tape storage system including at least one tape drive, the method comprising:
formatting the tape media so as to store an index of the file and data of the file in the tape media in a predetermined format;
splitting the single file into separate file portions and managing identifiers (IDs) identifying the plurality of tape media that sequentially store the file portions in association with the file; and
for each tape medium storing a file portion of the file, storing a generation number indicating a sequential number value corresponding to the file portion stored on the tape medium and updating the file portion stored on the tape medium, as part of the index, with the generation number corresponding to the file portion stored on the tape medium; and
in response to receiving a request to read the file from the tape storage system:
obtaining, by the tape storage system, an index on a tape medium storing a file portion whose corresponding generation number is the highest of the generation numbers of the separate file portions; and
reading, by the tape storage system, the obtained index of the file.
2. The spanning method according to claim 1, wherein in the predetermined format, the tape media are each divided into two or more partitions to allow the file system to read and write for sequential access of the storage system and the partitions include an index partition (IP) storing the index of the file and a data partition (DP) storing data on the file.
3. The spanning method according to claim 1, wherein the generation number is increased from a starting value to a next value each time a file portion is stored in another tape medium in the plurality of tape media or a file portion is modified on a tape medium.
4. The spanning method according to claim 1, wherein when a file portion is changed, the maximum value of the generation number is updated by increasing the value by one and is stored in the tape medium storing the file portion that was changed.
5. The spanning method according to claim 1, wherein an ID identifying the file is stored as part of the index in each of the tape media that store the file portions.
6. The spanning method according to claim 1, wherein each of the tape media that store the file portions each store, as part of the index stored on the tape medium, at least one of the IDs identifying the plurality of tape media that store other file portions of the file.
7. The spanning method according to claim 1, wherein a tape medium storing a first file portion further stores, as part of the index, an ID of a tape medium that stores a file portion preceding the first file portion and an ID of a tape medium that stores a file portion following the first file portion.
8. The spanning method according to claim 2, wherein in response to the tape storage system receiving a request to update a file portion, the tape storage system:
identifies an ID of a tape medium storing the file portion to be updated and mounts the tape medium in a drive;
stores the index on the tape medium having the ID into a memory of the tape storage system;
updates the data in the DP of the tape medium in an updated file portion;
updates the index stored in the memory as the data in the DP changes so as to reflect the updated file portion;
stores, in the updated index in the memory, an updated generation number of the file portion corresponding to the updated file portion; and
registers the updated index in the IP of the tape medium at a predetermined time.
9. A tape storage system for spanning a single file across a plurality of tape media, the tape storage system comprising:
at least one tape drive, and
a controller coupled to the at least one tape driver, wherein the controller is configured with logic that:
formats the tape media so as to store an index of the file and data of the file in the tape media in a predetermined format;
splits the single file into separate file portions and managing identifiers (IDs) identifying the plurality of tape media that sequentially store the file portions in association with the file;
for each tape medium storing a file portion of the file, stores a generation number indicating a sequential number value corresponding to the file portion stored on the tape medium and updating the file portion stored on the tape medium, as part of the index, with the generation number corresponding to the file portion stored on the tape medium; and
in response to receiving a request to read the file from the tape storage system:
obtaining, by the tape storage system, an index on a tape medium storing a file portion whose corresponding generation number is the highest of the generation numbers of the separate file portions; and
reading, by the tape storage system, the obtained index of the file.
10. A computer program product comprising a non-transitory computer readable medium comprising instructions for spanning a single file across a plurality of tape media in a tape storage system including at least one tape drive, the computer program product causing the tape storage system to:
format the tape media so as to store an index of the file and data of the file in the tape media in a predetermined format;
split the single file into separate file portions and managing identifiers (IDs) identifying the plurality of tape media that sequentially store the file portions in association with the file; and
for each tape medium storing a file portion of the file, store a generation number indicating a sequential number value corresponding to the file portion stored on the tape medium and updating the file portion stored on the tape medium, as part of the index, with the generation number corresponding to the file portion stored on the tape medium.
11. The computer program product according to claim 10, wherein the computer program product further causes the tape storage system, in response to receiving a request to read the file from the tape storage system, to obtain an index on a tape medium storing a file portion whose corresponding generation number is the highest of the generation numbers of the separate file portions and read the obtained index of the file.
12. The computer program product according to claim 10, wherein in response to the tape storage system receiving a request to update a file portion, the computer program product further causes the tape storage system to:
identify an ID of a tape medium storing the file portion to be updated and mounts the tape medium in a drive;
store the index on the tape medium having the ID into a memory of the tape storage system;
update the data in the DP of the tape medium in an updated file portion;
update the index stored in the memory as the data in the DP changes so as to reflect the updated file portion;
store, in the updated index in the memory, an updated generation number of the file portion corresponding to the updated file portion; and
register the updated index in the IP of the tape medium at a predetermined time.
13. The tape storage system according to claim 9, wherein in the predetermined format, the tape media are each divided into two or more partitions to allow the file system to read and write for sequential access of the storage system and the partitions include an index partition (IP) storing the index of the file and a data partition (DP) storing data on the file.
14. The tape storage system according to claim 9, wherein the generation number is increased from a starting value to a next value each time a file portion is stored in another tape medium in the plurality of tape media or a file portion is modified on a tape medium.
15. The tape storage system according to claim 9, wherein when a file portion is changed, the maximum value of the generation number is updated by increasing the value by one and is stored in the tape medium storing the file portion that was changed.
16. The tape storage system according to claim 9, wherein an ID identifying the file is stored as part of the index in each of the tape media that store the file portions.
17. The tape storage system according to claim 9, wherein each of the tape media that store the file portions each store, as part of the index stored on the tape medium, at least one of the IDs identifying the plurality of tape media that store other file portions of the file.
18. The tape storage system according to claim 9, wherein a tape medium storing a first file portion further stores, as part of the index, an ID of a tape medium that stores a file portion preceding the first file portion and an ID of a tape medium that stores a file portion following the first file portion.
19. The tape storage system according to claim 13, wherein in response to the tape storage system receiving a request to update a file portion, the tape storage system:
identifies an ID of a tape medium storing the file portion to be updated and mounts the tape medium in a drive;
stores the index on the tape medium having the ID into a memory of the tape storage system;
updates the data in the DP of the tape medium in an updated file portion;
updates the index stored in the memory as the data in the DP changes so as to reflect the updated file portion;
stores, in the updated index in the memory, an updated generation number of the file portion corresponding to the updated file portion; and
registers the updated index in the IP of the tape medium at a predetermined time.