1. A method for reading tag data of a compressed data file that includes compressed data and a data tag appended to the compressed data at a predetermined position, and performing a predetermined process based on a type of compressed data, comprising:
searching a starting position of the tag data in the compressed data file, retrieving the tag data, and then searching a starting position of the compressed data.
2. The method according to claim 1, wherein the searching includes searching the starting position based on an address of the starting position and a size of the compressed data file as well as a fixed length of the tag data.
3. The method according to claim 1, wherein if the tag data has a fixed length and is appended to the end of the compressed data, the searching includes searching the starting position by deducting the size of the tag data from an address of an ending position address of the compressed data file calculated based on the address of the starting position and the size of the compressed data file.
4. A computer-readable recording medium that stores therein a computer program that causes a computer to implement a method for reading tag data of a compressed data file that includes compressed data and a data tag appended to the compressed data at a predetermined position, and performing a predetermined process based on a type of compressed data, the computer program causing the computer to execute:
searching a starting position of the tag data in the compressed data file, retrieving the tag data, and then searching a starting position of the compressed data.
5. A device that reads tag data of a compressed data file that includes compressed data and a data tag appended to the compressed data at a predetermined position and performs a predetermined process based on a type of compressed data, comprising:
a searchingretrieving unit that first searches a starting position of the tag data in the compressed data file, retrieves the tag data, and then searches a starting position of the compressed data.
6. The device according to claim 5, wherein the searchingretrieving unit searches the starting position based on an address of the starting position and a size of the compressed data file as well as a fixed length of the tag data.
7. The device according to claim 5, wherein if the tag data has a fixed length and is appended to the end of the compressed data, the searchingretrieving unit searches the starting position by deducting the size of the tag data from an address of an ending position address of the compressed data file calculated based on the address of the starting position and the size of the compressed data file.
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 train integrity network system comprising two or more bogie units which monitor critical parameters relating to the condition of bogie components and the rail track they are travelling on, an onboard server which controls the bogie units and a wireless network which enables communication between the server and the bogie units.
2. The system of claim 1 wherein the bogie units have sensors to monitor the temperature of the hub of a bogie wheel.
3. The system of claim 1 wherein the bogie units have sensors to monitor the temperature of the periphery of a bogie wheel.
4. The system of claim 1 wherein the bogie units have motion detectors to monitor movement of the bogie axle in vertical and horizontal directions.
5. The system of claim 1 wherein the bogie units have accelerometers to monitor acceleration of the bogie axle.
6. The system of claim 1 wherein the bogie units have means to measure the speed of rotation of a bogie wheel.
7. The system of claim 1 wherein the bogie units are powered by an electrical generator which utilises the rotation of the bogie wheels.
8. The system of claim 1 wherein the bogie units have a processor which compares the critical parameters against defined standards.
9. The system of claim 1 wherein the bogie units have a wireless transceiver which enables communication with other bogie units and the server.
10. The system of claim 1 wherein the bogie units have a source of illumination.
11. The system of claim 1 wherein the wireless network utilises masterslave base band role switching.
12. The system of claim 1 wherein the wireless network has store-and-forward nodes which convey quasi real time data to the server.
13. The system of claim 1 wherein the wireless network utilises frequency hopping modes.
14. The system of claim 1 wherein the server can download data to a wayside database.
15. The system of claim 1 which also has a GPS unit to record the location of the train at any time.
16. The system of claim 1 which has an end-of-train monitoring function.
17. The system of claim 1 which has a collision avoidance function.
18. The system of claim 1 which has a level crossing warning function.
19. The system of claim 1 which transmits a warning signal to vehicles approaching a level crossing which are equipped to receive said signal.
20. The system of claim 1 which monitors tension and compression in the train wagon couplings.