This paper focuses on the performance analysis of ionosphere monitoring using the measurements from a BeiDou Continuously Operating Reference Stations (CORS) network. Combined pseudo-range and carrier phase observations are used to estimate total electron content (TEC) and the hardware delay deviation is also computed. Using the observations from five BeiDou CORS in China, the TEC monitoring results were obtained from each station and compared with GPS monitoring results and also those from the Global Ionosphere Maps (GIM) model. Numerical computation shows that the BeiDou system has the ability to precisely detect the TEC diurnal variation trend on each station. The Residual Mean Square (RMS) difference between the BeiDou and the GIM model at a higher latitude station is about four TEC Units (TECU), while the RMS difference between the GPS and the GIM is about three TECU; at a lower latitude station this difference increases to six

In the process of multi-cloud storage data migration, data integrity is vulnerable to corruption, but the existing data integrity verification schemes for data migration across clouds are not highly reliable. To address this problem, a blockchain-based data integrity verification scheme for migration across clouds is proposed in this paper. In this scheme, a blockchain network is used instead of a third-party auditor. For each migration, a multi-cloud broker will send an integrity verification request to blockchain at three different times, and a smart contract will verify the data integrity according to the RSA-based homomorphic verification tags. Then, the security of the scheme is analyzed. Finally, simulation experiments and tests are conducted on Ethereum, and the results show the feasibility of the scheme.

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During the past decades, fusion reactor fuels such as deuterium and tritium have been extensively investigated due to increasing interest in nuclear fusion energy. Tritium, which is scarce in nature, needs to be fabricated by tritium breeder materials. Among the commonly investigated tritium breeder materials, lithium titanate (Li2TiO3) is recognized as one of the most promising solid tritium breeder materials because of its considerable lithium (Li) atomic density, low activation, excellent chemical stability, and low-temperature tritium release performance. This paper aims to provide a systematic review of the current progress in Li2TiO3 preparation methods as well as the high Li density, tritium release performance, irradiation behavior, and modification technologies of Li2TiO3 pebbles. Li2TiO3 can be synthesized by strategies such as solid-state, sol–gel, hydrothermal, solution combustion synthesis, and co-precipitation methods. Among them, the hydrothermal method is promising due to its simplicity and low cost. Many researchers have begun to focus on composite ceramic pebbles to further improve tritium breeder performance. This will provide a new direction for the future development of Li2TiO3 pebbles. The present review concludes with a summary of the preparation methods currently under development and offers an outlook of future opportunities, which will inspire more in-depth investigation and promote the practical application of Li2TiO3 in this field.