Abstract: A device for detecting a slot wedge, an air gap and a broken rotor bar is provided, where a sequential circuit generates double concurrent pulses; the sequential circuit is connected to driving power modules; the driving power modules are connected to front-end interface circuits; the front-end interface circuits convert the double concurrent pulses into corresponding magnetic-field pulses; the magnetic-field pulses are transmitted to power supply terminals on adjacent phases of stator windings through impedance matching pins and coupled at a corresponding coil, air gap and squirrel cage rotor to generate single groups of cyclic rotating magnetic potentials; single rotating magnetic potentials are sequentially generated in adjacent slots on each of the phases of the stator windings; rotating electric potentials in magnetic circuits with two symmetrical phases are magnetically coupled to form distributed coupling magnetic field reflected full-cycle waves for reflecting a difference of a corresponding slot wedg

Abstract: A method, an apparatus, and a system for subscription and notification are disclosed. The method includes the following steps: a Home Subscriber Server Front-End (HSS FE) receives a first subscription request which is sent by an Application Server (AS) and carries data content that the AS requests to subscribe to; the HSS FE sends a second subscription request to a convergent database, where the first subscription request and the second subscription request have a subscription relation; the HSS FE receives a notification sent by the convergent database according to the second subscription request; and the HSS FE sends data content carried in the notification to the AS according to the subscription relation. The present invention enables the AS to obtain the subscribed data from the HSS FE.