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The correlation of earthquakes with tremor and slow slip has not been clearly quantified. We investigate 12 year earthquake and tremor catalogs for southwest Japan and find that nearby small intraslab earthquakes are weakly correlated with tremor. In particular, the intraslab earthquakes with magnitudes ≥2.7 tend to be followed by tremor more often than expected at random by a factor of 2 to 6. The excess number of tremor before earthquakes is not as significant, although marginally more than expected. The underlying physical mechanism of the observed triggering of tremor and inferred slow slip by earthquakes is most likely to be the dynamic stress changes (several to several tens of kilopascals) rather than the much smaller static stress changes. The rate of triggering of tremor by earthquakes is similar to, although somewhat lower than, rates observed for similar amplitude stress changes due to the lower-frequency teleseismic surface waves and tidal stressing.

In order to improve the safety, stability, and efficiency of lane change operating, this paper proposes a multivehicle-coordinated strategy under the vehicle network environment. e feasibility of collaborative lane change operation is established by establishing a gain function based on the incentive model. By comparing lane change gain with lane keeping gain, whether it is feasible to perform the collaboration under current conditions can be judged. Based on the model predictive control (MPC), a multiobjective optimization control function for cooperative lane change is established to realize the distributed control. A novel two-stage cooperative lane change framework is proposed, which divides the lane change process into the lane change phase and the longitudinal headway adjustment phase. It is significant to solve the difficult numerical problem caused by the dimension of collision-avoidance constraints and the nonlinearity of vehicle kinematics. In the first stage, the subject vehicle completes lane change operation. Both longitudinal and lateral movements of the vehicle are considered to optimize the acceleration and the error of following distance at this stage; in the second stage, the operation of adjusting longitudinal headway between vehicles in the target lane is completed, and at this period, only the longitudinal motion of the vehicle is considered to optimize the vehicle acceleration error. e rolling optimization time domain algorithm is used to solve the optimization control problem step by step. Finally, based on the US NGSIM open-source traffic flow database, the accuracy and feasibility of the proposed strategy are verified.