A method and apparatus for using prior results when processing successive database requests. After the head lamps 2 are moved backward of a vehicle along a predetermined trajectory by being slid along the guide grooves 16, the projecting portions 30 are disengaged backward out of the guide grooves 16 of the receiving parts 15 in such a way that the head lamps 2 are fixed on a vehicle body in a state where a certain clearance H1 is formed below the projecting portions 30. The housing includes at least one cooling protuberance extending into the open volume. The materials of the electrochromic layers in these devices exhibit broadband optical complimentary behavior, ionic species complimentary behavior, and coloration efficiency complimentary behavior in their operation. The system may further include a model having one or more elements, and an asset retrieval module to selectively retrieve a subset of the software assets from the asset library based on input from a user identifying one or more of the elements. An FFT engine is used to transform a time domain input sequence, the transformed sequence is multiplied by the conjugate of the expected sequence, the product of several sequences is averaged, then the FFT engine transforms the average back to a time domain sequence, the magnitude of which is the impulse response of the channel.