This is an example over a 10Gb/s link, and the packet size is 1500 bytes.
A UDT flow will start at 0 and increase its sending rate by 10 packets per SYN before it reaches 9Gb/s. After that, the increase parameter becomes 1 packet per SYN, and 0.1 packet per SYN, and so on.
In fact, UDT can scale up to 90% of the bandwidth at approximately a constant time, which is 750 SYN, or 7.5 seconds. This makes UDT very scalable to the increase of network bandwidth and delay.