WE CLAIM:
1. An operation status reproducing device to reproduce an
operation status of a train based on onboard information
managed by an onboard device mounted on each train of a
railway system and ground information managed by a ground
device to monitor an operation status of each train of the
railway system, the operation status reproducing device
comprising:
an onboard information obtaining unit to obtain the onboard information corresponding to date and time from the onboard device mounted on a designated train being a train specified by a train number and the date and time externally designated;
a specific event detecting unit to specify time at which a specific event occurs by analyzing the onboard information obtained by the onboard information obtaining unit;
a ground information obtaining unit to obtain the ground information in a certain period including the time at which the specific event occurs from the ground device;
an external information obtaining unit to obtain external information including weather information in a certain period including the time at which the specific event occurs; and
a reproduction image generating unit to generate a reproduction image illustrating a past operation status of the designated train based on the onboard information, the ground information, and the ground information.
2. The operation status reproducing device according to
claim 1, further comprising:
a display device to display the reproduction image generated by the reproduction image generating unit.

3. The operation status reproducing device according to
claim 1,
wherein a display device forming the onboard device is allowed to display the reproduction image generated by the reproduction image generating unit.
4. The operation status reproducing device according to
claim 1,
wherein the reproduction image generating unit includes:
a display information reproducing unit to generate display information for reproducing an image and character information displayed on a display device installed in an operator's room of the designated train based on the onboard information in the certain period;
a device operating information reproducing unit to generate operating information for reproducing contents of operation executed on a device mounted on the designated train based on the onboard information in the certain period;
a ground information reproducing unit to generate operation status reproduction information for reproducing an operation status of the designated train based on the ground information in the certain period;
an external display information generating unit to generate external display information indicating weather in a travel position of the designated train based on the external information in the certain period; and
a display information synthesizing unit to generate the reproduction image by synthesizing the display information, the operating information, the operation status reproduction information, and the external display

information.
5. The operation status reproducing device according to
claim 4, further comprising:
a storage unit to hold the display information, the operating information, the operation status reproduction information, and the external display information as reproduction information; and
a reproduction control unit to read out the reproduction information from the storage unit and output to the display information synthesizing unit, and make the display information synthesizing unit generate the reproduction image based on the output reproduction information.
6. The operation status reproducing device according to
claim 5,
wherein the reproduction control unit executes a process of erasing the oldest reproduction information from the storage unit when the reproduction information held by the storage unit exceeds a certain value and a process of erasing the reproduction information recorded prior to current date and time by a certain period or longer out of the reproduction information held by the storage unit from the storage unit.
7. The operation status reproducing device according to
claim 1, further comprising:
an audio reproducing unit to generate audio information output when the designated train is operated based on the onboard information in the certain period.
8. A display device that displays the reproduction image

generated by the operation status reproducing device according to claim 1.
9. An operation status reproducing method to reproduce an operation status of a train based on onboard information managed by an onboard device mounted on each train of a railway system and ground information managed by a ground device to monitor an operation status of each train of the railway system, the operation status reproducing method comprising:
obtaining the onboard information corresponding to date and time from the onboard device mounted on a designated train being a train specified by a train number and the date and time externally designated, by an onboard information obtaining unit;
specifying time at which a specific event occurs by analyzing the obtained onboard information, by a specific event detecting unit;
obtaining the ground information in a certain period including time at which the specific event occurs from the ground device, by a ground information obtaining unit;
obtaining external information including weather information in a certain period including the time at which the specific event occurs, by an external information obtaining unit; and
generating a reproduction image illustrating a past operation status of the designated train based on the onboard information, the ground information, and the ground information, by a reproduction image generating unit.