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Accurately and quantitatively monitoring the damages in composite structures is very challenging, but important for assessing their integrity. In this paper, an innovative damage location identification and size quantification assessment method based on Lamb wave is proposed for composite laminates. A continuous hidden Markov model (CHMM)-based damage scaling factor together with a weighted average imaging algorithm is adopted in damage location identification. To quantify the degree of structural deviation from the healthy state, the inconspicuous change of guided wave (GW) signal is converted to a CHMM-based damage scaling factor with significant change. Based on the damage scaling factors of all GW sensing paths, a weighted average imaging algorithm is performed to identify the most probable damage location. In addition, a damage quantitative mathematical expression is proposed to approximately estimate the size of circular-shaped damage founded on several different damage-related characterizations. The implementation of the proposed quantitative methodology is comparatively simple and straightforward for damage detection. Experiments on three composite panels with multiple damage cases are conducted to substantiate the proposed method. The sensor layers with embedded piezoelectric transducer (PZT) sensor networks surf-mounted on the structures are employed to excite and receive Lamb wave signals since their superiority of flexibility, electrical stability and apt for complex structures. The results demonstrate that the proposed algorithm is capable of pinpointing both the location and size of the circular-hole damage in composite structures. [ABSTRACT FROM AUTHOR]

• A comprehensive review of disulfide-based polymeric nanomedicines. • A tutorial review on the construction of core and shell crosslinked responsive nanomedicines. • Detail guides on disulfide-based polymer-drug conjugates and dimeric prodrugs. Disulfide bonds (S-S) are widely found in chemistry, biology, and materials science. Polymer nanomaterials containing disulfide bonds with a variety of excellent properties have great potential as drug and gene delivery carriers. The disulfide bond can exist stably in extracellular environment, but upon entering cancer cells, it will undergo a sulfhydryl-disulfide bond exchange reaction with glutathione (GSH) in the cytoplasm, causing the disulfide bond cleavage. Therefore, polymeric nanomaterials containing disulfide bonds are promising in cancer treatment due to the elevated GSH concentration inside cancer cells. This review highlights various synthetic approaches to prepare disulfide containing redox-responsive polymeric nanomedicine, including synthesis of disulfide bonds containing polymers, construction of polymeric nanoparticle with shell or core crosslinked disulfide bonds, preparation of polymer-drug conjugates via disulfide linkers, and disulfide linked responsive payloads. [ABSTRACT FROM AUTHOR]