Sorry for the long downtime. On June 8th 2016, two disks in ZOJ's RAID 5 system were corrupted. Unfortunately, serious data loss was resulted in this accident.
We will roll back ZOJ to some day in 2015, which means data in nearly a year will disappear. Registration and submission information during this period cannot be found. We grieve on the loss. Still, we will not stop trying to bring back the lost data.
Sorry again for all the inconvenience and loss resulted.