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The Tengchong Cenozoic volcano is located near the collision boundary between the Indian and Eurasian plates. The tectonic activity in this area is strong, and the volcano has a potential for eruption. Studying the origin of the Tengchong volcano is important for understanding plate subduction processes and the mechanism of volcano eruption. This review first summarizes the latest researches on the origin of the Tengchong volcano, including new advances in geophysics and geochemistry, and then discusses the magma source and deep dynamic mechanism. These studies have found that the genesis of Tengchong volcanism is mainly related to plate subduction. The subducted residual oceanic plate and the currently subducting Indian plate may both contribute to the source of metasomatic materials. The oceanic plate released melt and fluid to form metasomatized asthenospheric and lithospheric mantles, and Tengchong magma originated from the mixing of lithospheric and asthenosphere mantle melts. The metasomatized lithospheric mantle is characterized by low 3He/4He (< 7.0 Ra) and Nb/La (average of 0.36) ratios as well as high 87Sr/86Sr (average of 0.707928) and La/Yb (average of 22.0) ratios. In contrast, the enriched asthenospheric mantle is characterized by high 3He/4He (> 7.0 Ra) and Nb/La (average of 0.52) ratios with relatively low 87Sr/86Sr (average of 0.706708) and La/Yb (average of 17.0) ratios. The increasing trend of 3He/4He ratios and decreasing trend of 87Sr/86Sr ratios over time suggest that the contribution of the metasomatized lithospheric mantle decreased relative to that of the enriched asthenosphere after the late Pleistocene, reflecting the progressive lithospheric extension and thinning. Tengchong basalts do not show clear correlation between 87Sr/86Sr ratio and SiO2 content, whereas basaltic andesite, andesite, and dacite display positive correlation between 87Sr/86Sr ratio and SiO2 content. This phenomenon indicates that Tengchong basalt suffered limited crustal contamination, while basaltic andesite, andesite, and dacite underwent obvious crustal contamination. Moreover, seismic imaging along with magnetotelluric and geothermal studies revealed several magma chambers (low-speed anomalies) in the crust beneath the Tengchong volcano. However, the size and depth of the magma chambers vary between different studies. The low-velocity bodies in the crust extend downward to the upper mantle, which may indicate that the magma chambers in the crust are fed by hot materials from the upper mantle. However, a consensus on the origin of hot materials has yet to be reached. Seismic tomography studies suggest that hot materials could be generated from the dehydration of the stagnant slab in the mantle transition zone, tearing of the subducted plate, or slab rollback. Differences in seismic imaging results may be caused by the limited observation data, data imaging methods, and the multi-solution of geophysical inversion. The utilization of more data and advanced geophysical methods will help obtain high-resolution imaging results to further constrain the origin of the Tengchong volcano.

The previously proposed short comparable encryption (SCE) scheme can infer the plaintext relationship by comparing the ciphertexts relationship as well as ensuring data security in Internet of things.Unfortunately,it will incur high storage and computational burden during the process of comparing ciphertexts and generating tokens.To this end,an efficient short comparable encryption scheme called SCESW was proposed,which was utilizing the sliding window method with the same size window.Formal security analysis shows that the scheme can guarantee weak indistinguishability in standard model as well as data security and integrity.The experimental results demonstrate that the storage of the SCESW scheme is 1 t (t＞1) times shorter than that of the SCE scheme and the efficiency of the SCESW scheme is superior to that of the SCE scheme.

The previously proposed short comparable encryption (SCE) scheme can infer the plaintext relationship by comparing the ciphertexts relationship as well as ensuring data security in Internet of things.Unfortunately,it will incur high storage and computational burden during the process of comparing ciphertexts and generating tokens.To this end,an efficient short comparable encryption scheme called SCESW was proposed,which was utilizing the sliding window method with the same size window.Formal security analysis shows that the scheme can guarantee weak indistinguishability in standard model as well as data security and integrity.The experimental results demonstrate that the storage of the SCESW scheme is 1 t (t＞1) times shorter than that of the SCE scheme and the efficiency of the SCESW scheme is superior to that of the SCE scheme.