A recent experimental observation of a neutron flux burst at a rate of 2 × 104 times the background rate during a high-ac voltage stimulation between two deuterated palladium electrodes in D2 gas is explained in terms of the experimentally measured deuterium-deuterium (D-D) fusion cross sections. Theoretical criteria and experimental conditions for improving D-D fusion rates with the use of pulsed high-dc voltages are described.