A method is disclosed wherein a plurality of sensors mounted on a structure, a baseline data set for each of the plurality of sensors and a calibration procedure verify the integrity of a structural health management system. The silicon nitride porous body has a porous structure with a large average pore diameter, a test specimen cut out from the porous body exhibiting a high thermal conductivity and a small thermal expansion coefficient, and can be suitably used in a component for purifying gas andor solution such as a ceramic filter. The further signal combiner is arranged for combining at least part of the input signals into at least one auxiliary signal The multi-channel filter is asymmetric in that at least one of the filters has a filter length which is substantially larger than the filter lengths of the other filters. Controlling location, speed and shape of the burnfront manages neutron fluence seen by fuel assembly structural materials in order to reduce risk of temperature and irradiation damage to the structural materials. In still other embodiments, a neck reinforcement is positioned along a portion of the neck for increased strength. Acoustic sensing of a wellbore, pipeline, or other conduittube based on DAS may have increased acoustic sensitivity through fiber optic cable design andor increasing the Rayleigh backscatter property of a fiber’s optical core.