Tao: Would lots of energy be lost at the corner (turn around) 
And how this effect would be compensated ? 
Ryuta:Energy loss of e-(e+) by one circulation,the calculation result maybe is 0.1%.
Xin:Why ILC has to run in push-pull mode ?what is the main difference on the tracker between SiD &ILD ?
Ryuta:So far, I only found statements such like "we need cross-check and compete "
Maoqiang:What does "disk"means ?
Ryuta:There is a disk in the SiD detector,but no disk in ILD,you can see in the picture.
Maoqiang:Why dose the SiD have a disk, and the ILD have no disk?
Xin:Maybe for design considering.