A novel device for controlling the compression pressure of an internal combustion engine is disclosed. The Level 2 cache is further partitioned into a number of slots which are dynamically allocated to texture maps as needed. , the difference between the absorbance at a wavelength of 395 nm and the absorbance at a wavelength of 800 nm is at least 0. Finally, there is a a return member arranged so as to urge the second flap against an abutment of the first flap that prevents the second flap from becoming aligned with the first flap, and to urge the first flap against an abutment of the stationary support that prevents the first flap from folding against the support. Beneficially, the health risks associated with fluoroscopy and endoscopy are thereby eliminated or reduced with their associated disuse thereof. The slanted periodically poled device 12 is configured to generate the up-conversion signal beam A in the same direction as and in parallel with the pump beam 1 by quasi phase matching between the terahertz wave 3 perpendicularly incident from the terahertz wave input surface 12c and the pump beam 1.