For the problems of poor enhancement effect and long time consuming of the traditional algorithm, an adaptive smoothness constraint image multilevel fuzzy enhancement algorithm based on secondary color-to-grayscale conversion is proposed. By using fuzzy set theory and generalized fuzzy set theory, a new linear generalized fuzzy operator transformation is carried out to obtain a new linear generalized fuzzy operator. By using linear generalized membership transformation and inverse transformation, secondary color-to-grayscale conversion of adaptive smoothness constraint image is performed. Combined with generalized fuzzy operator, the region contrast fuzzy enhancement of adaptive smoothness constraint image is realized, and image multilevel fuzzy enhancement is realized. Experimental results show that the fuzzy degree of the image is reduced by the improved algorithm, and the clarity of the adaptive smoothness constraint image is improved effectively. The time consuming is short, and it has some advantages.

Now there’re many researches on the electromagnetic radiation protection function of the cement-based electromagnetic wave absorbing materials, such materials have been widely used in various types of buildings. This paper proposed an idea for preparing a cement-based composite material by mixing functional aggregates with high content of Fe2O3 and SiC, that is, adding Fe3O4 powder and nano-SiC of different contents in the clay, and then sintering at 1190℃; the prepared aggregates showed obvious magnetic loss and dielectric loss to electromagnetic waves, and the numerical tube pressure could reach 16.83MPa. The double-layer reflectivity test board made of functional aggregates showed excellent electromagnetic wave absorption performance, its reflection loss was less than -10dB in the frequency range of 8~18GHz (corresponding to energy absorption greater than 90% EM), and its maximum RL reached -12.13dB. In addition, the compressive strength of the cement-based composite material at the age of 28 days reached 50.1 MPa, which can meet the strength requirements of building materials.

Based on the application of stealth technology in actual engineering projects, and according to the theory that when electromagnetic waves (EMW) pass through different wave absorbing materials, they will undergo resistance loss, dielectric loss, and magnetic loss, and the electromagnetic energy will be converted into thermal energy, this paper designed and developed a dual-layer EMW-absorbing Cement Matrix Composites (CMC) combining with the principle of impedance matching, and proposed to take cement paste mixed with expanded perlite as the matching layer of the newly developed material, and aggregate and nanomaterials as its wave absorbing layer. The aggregate was prepared by mixing 15wt.% 38μm Fe3O4 powder and 10wt.% 500nm SiC powder into the clay powder to produce cement raw pellets and calcine them at 1190℃, the fabricated aggregate has obvious dielectric loss and magnetic loss to EMW, and its crushing resistance strength can reach 13.7MPa. For the dual-layer test pieces made of the prepared aggregate and 2wt.% Conductive Carbon Black (CCB), within 8-18GHz frequency band, the bandwidth with a reflectivity lower than -10db reached 9.5GHz, the bandwidth with a reflectivity lower than -12db reached 7.55 GHz, and its maximum reflection loss reached -19.56db. In addition, the prepared CMC exhibited good mechanical properties, and its compressive strength reached 50.7MPa at the age of 28d.

An innovative cellular concrete procured with sat-SAP (superabsorbent polymer) is introduced. Combined with BFRP bars, this concrete may play a role as protective structures in marine applications. Eight BFRP-reinforced cellular concrete slabs (BSs) and three steel-reinforced normal concrete slabs (SPs) are exposed to simulated blast loadings in a shock tube device. Low-modulus cellular concrete and BFRP bars cause BSs to exhibit distinctive behaviours compared to those of SPs. BSs, which are more flexible at the same reinforcement ratio, have more intensive vibrations and larger deformations compared to SPs under various blast loadings. In addition to the porous structure of cellular concrete, BSs demonstrate better wave-attenuating and energy-absorbing abilities. More severe damage such as cracks, deflections, and breaches is observed for BSs. In the current research, a comprehensively superior blast resistance can be achieved through improving reinforcement ratio to promote serviceability.

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