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The remote direct memory access (RDMA) technology, which has been effectively utilized to enhance data transfer rates and reduce CPU utilization, has played a significant role in various domains such as cross-regional data center transfers, high-performance computing, and rapid data read/write operations. However, despite its emerging status, RDMA has been lacking in widely recognized security solutions. With the expansion of RDMA applications from dedicated network environments to general Ethernet networks, the need to address the security risks faced by these applications has become imperative. A set of protective measures were established to ensure security without compromising transmission efficiency. Furthermore, the unique underlying implementation and protocol design of RDMA technology have resulted in incompatibility with existing mature security solutions and have led to the confrontation with specific security risks. The development of RDMA attack and defense technologies and the provision of security guarantees for the forthcoming widespread application of RDMA technology were elucidated The principles of RDMA technology and its implementation were proposed, with examples drawn from the InfiniBand (IB) and the RDMA over converged Ethernet (RoCE) second edition protocols. The security risks faced by RDMA applications in relevant scenarios were investigated, and a summary of the research progress in the RDMA security field over recent years was provided. Effective security solutions addressing these risks were compiled and, after their defensive capabilities were proven, a comparison of their advantages and disadvantages was conducted through theoretical analysis and experimental data. Finally, improvement plans and prospects for technological optimization in the RDMA attack and defense field were proposed.

In order to further reduce the tritium abundance of hydrogen isotope exhaust with low tritium content, realize the recovery of tritium efficiently, and reduce the impact of tritium emission sources on the environment, this paper carried out the research of low-abundance tritium recovery process based on thermal cycle adsorption process. When the separation column packed with palladium deposited on kieselguhr (Pd/K) is at low temperature, hydrogen isotope gas is injected from the front end, and then the column is controlled to perform a heating-cooling cycle. After several cycles, the light component argon is enriched at the inlet of the separation column, and the recombinant tritium concentration is concentrated at the outlet. The research showed that the gas with a tritium abundance of 3.2% entered the experimental system, and after 7 cycles, the tritium abundance at the inlet of the separation column is less than 0.01%. A total of 7.55 mol of low-abundance gas is processed in the experiment, and finally 7.42 mol of the exhaust gas with a tritium abundance of less than 0.05% was extracted, as well as 72.31 mmol of tritium gas with an abundance of 98.68% and 0.048 mol of a medium-abundance gas with an average abundance of 29.68%. The system tritium recovery rate reached 99.54%. Experiments have verified that the thermal cycle adsorption optimization process can further reduce the tritium abundance in the exhaust gas and directly obtain high-abundance tritium gas products, greatly increasing the effective extraction of tritium.

A two-step identification method is proposed, both the moment of inertia and the mass properties are identified. A new index parameter which is different from the commonly used condition number is first defined for designing the optimal excitation. A method is introduced based on the least squares algorithm. Detailed mathematical equations and numerical analysis are proposed. Simulation results show that the proposed method can identify the mass parameters of spacecraft.