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The influences of road adhesion coefficients on vehicle control were analyzed. The vehicle-road dynamics model was obtained according to the vehicle linear two degrees of freedom models and certain preview informations. An estimation algorithm of road adhesion coefficients was presented based on Brush tire model, in view of the time delay between yaw speed and steering angle, an adaptive time coefficient related to the road adhesion coefficients was put forward and added to the vehicle- road dynamics model. Based on the sliding mode control theory, the yaw rate sliding mode controllers were designed to track the desired vehicle state and obtain an ideal steer angle. Finally, based on Car-Sim/Simulink simulation and HIL tests, the effectiveness of lane keeping control considering the adaptive time coefficient under different road adhesion coefficients are improved. [ABSTRACT FROM AUTHOR]

Current research on lane-keeping systems ignores the effect of the driver and external resistance on the accuracy of tracking the lane centerline. To reduce the lateral deviation of the vehicle, a lane-keeping control method based on the fuzzy Takagi-Sugeno (T-S) model is proposed. The method adopts a driver model based on near and far visual angles, and a driver-road-vehicle closed-loop model based on longitudinal nonlinear velocity variation, obtaining the expected assist torque with a robust H∞ controller which is designed based on parallel distributed compensation and linear matrix inequality. Considering the external influences of tire adhesion and aligning torque when the vehicle is steering, a feedforward compensation control is designed. The electric power steering system is adopted as the actuator for lane-keeping, and active steering redressing is realized by a control motor. Simulation results based on Carsim/Simulink and real vehicle test results demonstrate that the method helps to maintain the vehicle in the lane centerline and ensures driving safety. [ABSTRACT FROM AUTHOR]

DNA methylation is one of the earliest and most extensively studied epigenetic regulatory mechanisms. The ROS1 (Repressor of Silencing 1) gene was first discovered in Arabidopsis thaliana , and it is a DNA demethylase that can remove 5-methylcytosine from DNA, thereby affecting DNA methylation levels and gene expression. Objectives : The objective of this study was to investigate the role of ROS1 in the development and maturation of Ziziphus jujuba cv. "Dongzao" fruit. Methods : We cloned the ROS1 gene and conducted bioinformatics and expression characteristics analyses on it. Results : Three ROS1 genes, named ZjROS1-1~3 , was identified, and each member protein was localized in the nucleus, cytoskeleton, chloroplast, and vacuole. The promoter contained cis -elements such as light response, plant hormone signal transduction, and stress response cis -elements, and it interacted with many proteins such as CMT, MET, and ZDP. The results of the real-time fluorescence quantitative PCR show that ZjROS1 has specific expression patterns in different tissues of Z. jujuba cv. Dongzao, and the expression of ZjROS1-2 in flowers and fruits is high. At the same time, CRISPR/Cas9 technology was used to construct a gene-editing vector for ZjROS1 , which provided a basis for the subsequent genetic transformation. Conclusions : In this study, the biological function of ZjROS1 was clarified and a gene-editing vector was constructed, which provided a theoretical basis for the regulation mechanism of demethylase ZjROS1 in the fruit ripening and development of Z. jujuba cv. Dongzao.

In the mononuclear Ti(IV) title complex, [Ti(C29H33NO2)(C3H6O)2], the TiNO4 coordination polyhedron comprises an N-atom and two O-atom donors from the dianionic Schiff base ligand and two O-atom donors from monodentate isopropoxide anions. The stereochemistry is distorted trigonal-bipyramidal with the N-donor in an elongated axial site [Ti-N = 2.2540 (17) Å], the O-donors having normal Ti-O bond lengths [1.7937 (14) Å (axial)-1.8690 (14) Å]. In the crystal, C-H⋯π inter-actions link mol-ecules into centrosymmetric dimers.