A cooling system for apparatus powered by electricity, that generates a substantial amount of heat during operation, and the heat must be dissipated to avoid failure of electrical andor electronic components, such as semiconductor devices and integrated circuits, comprising the electrical apparatus. The device includes means to open and close, at least partially, the lateral outlet edges so as to be able to carry out an initial introduction of at least one blast of compressed air into the splice box when the lateral outlet edges are mostly closed, and a second introduction of at least one blast of compressed air into the splice box when the lateral outlet edges are mostly or completely open. The entire processing is done on the spatio-temporal correlation coefficient sequence of the observed data in order to avoid large matrix-vector multiplications.