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Time synchronization is crucial for effective collaboration among underwater sensors. However, existing synchronization protocols primarily cater to low-speed or simple motion scenarios, neglecting variations in radial velocity during message propagation. A novel Doppler compensation time synchronization scheme, called DC-Sync, was developed in this study to address this issue by targeting complex moving underwater sensors. DC-Sync includes a practical Doppler compensation and estimation method. Simulation results demonstrate that when the target motion follows a specific pattern, DC-Sync outperforms existing similar schemes in terms of time skew and time offset accuracy. Furthermore, the scheme maintains high estimation accuracy even with incomplete Doppler measurement values. Its performance was also validated through physical experiments.

Objective To investigate the value of MRI diffusion-weighted imaging (DWI) technique in endocrine therapy for prostate cancer (PCa) based on PI-RADSv2.1. Methods A retrospective analysis of 57 patients with pathologically confirmed PCa was conducted. All patients underwent multi-parametric MRI (mpMRI) according to PI-RADS v2.1 technical specifications before biopsy and six months after endocrine therapy. The apparent diffusion coefficient (ADC) values were measured in cancer and non-cancer areas before biopsy and six months after endocrine therapy. Patients were grouped based on the mRECIST criteria and PSA level into responders (n=45) and non-responders (n=12). ROC curves were obtained to assess the correlation between changes in ADC values and PSA values before and after endocrine therapy. Results In the responder group, the ADC value of the cancer areas was increased significantly after endocrine therapy (P

In underwater clustering and benchmark networks, nodes need to reduce the rate and energy consumption of acoustic communication while ensuring synchronization accuracy. In large-scale networks, the improvement in the efficiency of existing network time synchronization often relies on the optimization of topological structures, and the improvement in efficiency within local areas is limited. This paper proposes a method to synchronize underwater time using the probability graph model. The method utilizes the positional and motion status information of sensor networks to construct a factor graph model for distributed network synchronization. By simplifying the marginal probability density function of the system clock difference, it can quickly calculate the clock difference parameters of nodes, thereby effectively improve the synchronization efficiency. The experimental results show that the method can complete global time synchronization within a cycle while achieving a clock difference correction accuracy higher than seconds, which significantly optimized the synchronization cycle and efficiency, and reduced the energy consumption of the acoustic communication. [ABSTRACT FROM AUTHOR]