The ?l? ?r? r?r? ?kp?r?kp? ?kachamara na teknuzu imek? ihe ?n? na Chengdu University of Information Science and Technology na National Key Laboratory of Traction Power nke Southwest Jiaotong University The ?l? ?r? si sayens? nnyocha lar?? na nkà na ?z? nnyocha na mmepe ike na-aga n'ihu na-ejiri na mma na N'otu oge ah?, ?l? ?r? ah? na-aga n'ihu na-eme ka ? d?kwuo mma n'af? nd? na-ad?begh? anya iwebata ?t?t? nd? ?kachamara p?tara ìhè na ?l? ?r? ah? na-enye nkwado siri ike maka njikwa ?l? ?r? na ike ?r?.