A cross-flow ion mobility spectrometer consists of two parallel plates defining a volume between them. Each feedback waveguide precedes one of the second mirrors, and a phase detector to detect an error in a wavelength of a received laser beam with respect to a desired wavelength. This is due, in part, to water in the electrolyte attacking the thin film of aluminum oxide formed on the anode surface. The lifting gas will be injected to the wellbore proximately at perforation intervals for helping unloading liquid and producing the well. In one embodiment, an integrated contact center comprises: a workforce manager comprising a scheduler and a tracking function; and a lesson assignment function configured to receive at least one indicator of performance of the agent, and further configured to assign a lesson to the agent based on the at least one indicator.