3 research outputs found
Multiparameter Optimization Framework of Cyberphysical Systems: A Case Study on Energy Saving of the Automotive Engine
Multiparameter optimization of complex electromechanical systems in a physical space is a challenging task. CPS (Cyberphysical system) technology can speed up the solution of the problem based on data interaction and collaborative optimization of physical space and cyberspace. This paper proposed a general multiparameter optimization framework by combining physical process simulation and clustering genetic algorithm for the CPS application. The utility of this approach is demonstrated in the instance of automobile engine energy-saving in this paper. A 1.8-L turbocharged GDI (gasoline direct injection) engine model was established and calibrated according to the test data and physical entity. A joint simulation program combining CGA (Clustering Genetic Algorithm) with the GDI engine simulation model was set up for the engine multiparameter optimization and performance prediction in cyberspace; then, the influential mechanism of multiple factors on engine energy-saving optimization was analyzed at 2000 RPM (Revolutions Per Minute) working condition. A multiparameter optimization with clustering genetic algorithm was introduced for multiparameter optimization among physical and digital data. The trade-off between fuel efficiency, dynamic performance, and knock risk was discussed. The results demonstrated the effectiveness of the proposed method and that it can contribute to develop a novel automotive engine control strategy in the future
Extension Coordinated Multi-Objective Adaptive Cruise Control Integrated with Direct Yaw Moment Control
An adaptive cruise control (ACC) system can reduce driver workload and improve safety by taking over the longitudinal control of vehicles. Nowadays, with the development of range sensors and V2X technology, the ACC system has been applied to curved conditions. Therefore, in the curving car-following process, it is necessary to simultaneously consider the car-following performance, longitudinal ride comfort, fuel economy and lateral stability of ACC vehicle. The direct yaw moment control (DYC) system can effectively improve the vehicle lateral stability by applying different longitudinal forces to different wheels. However, the various control objectives above will conflict with each other in some cases. To improve the overall performance of ACC vehicle and realize the coordination between these control objectives, the extension control is introduced to design the real-time weight matrix under a multi-objective model predictive control (MPC) framework. The driver-in-the-loop (DIL) tests on a driving simulator are conducted and the results show that the proposed method can effectively improve the overall performance of vehicle control system and realize the coordination of various control objectives
Genetic Analysis of <i>S5</i> Regulating the Hybrid Sterility between <i>Indica</i> and <i>Japonica</i> Subspecies in Rice
Hybrid sterility is the major obstacle to the utilization of inter-subspecific heterosis in hybrid rice breeding. The S5 locus, composed of three adjacent genes ORF3, ORF4, and ORF5, plays a crucial role in regulating indica/japonica hybrids’ female sterility. Through a series of crosses involving 38 parents, three alleles of S5, ORF3+ORF4−ORF5n, ORF3+ORF4+ORF5n, and ORF3−/ORF4−/ORF5n, all could be regarded as wide-compatibility alleles, and when crossed with indica or japonica rice, they all showed significantly high fertility. Then, in order to explore the genes’ function, we further knocked out genes by using CRISPR/Cas9-based genome editing. Our results demonstrate that the ORF3+ was not just the protector in the killer-protector system, and knocking out ORF3 of the indica allele seriously affected the rice’s normal development. We observed the concrete enhancing hybrid spikelet fertility from the crosses between the ORF4+ knockout japonica materials with indica varieties. By conducting the comparative RNA-Seq analysis of young spikelets, we found that the ORF4+/ORF4− could modulate the hybrid fertility by affecting the expressions of genes related to the function of the Golgi apparatus. This study indicated that knocking out the ORF4+ of the japonica allele or using the alleles carrying ORF5n would provide effective approaches to overcome indica/japonica hybrid female sterility in rice breeding