No abstract

When tractor steers in the same rut, it can not only improve its flexibility in steering, but also reduce soil compaction and crop rolling. In this paper , the concept of tractor steering in the same rut was proposed on the basis of four-wheel-steering (4WS) theory, and the angle relationship between front wheel and rear wheel, which can achieve the same-rut-steering, was established. A three dimensional parameterized model of tractor’s same-rut-steering mechanism was established by the Pro/E software, and its running tracks were simulated in the ADAMS environment. Simulation results show that the same-rut-steering accuracy was affected to some extent when tractor’s speed or steering wheel deflection rate was changed. At last, methods for improving the same-rut-steering accuracy were put forward.

It is quite obvious that multi-branch tree search algorithm could be used for higher identification efficiency in RFID, however the branch number choosing depends on the accurate tag number estimation, which is not so easy to get and often cost much overhead. In this paper, we propose an adaptive multi-branch tree anti-collision algorithm. It begins with a simple initial tag number estimation, and then adaptively adjusts the branch groups afterwards. Simulation results indicate that the proposed algorithm can effectively correct the improper branch number and achieve much better performance than the conventional one.

To implement GMSK modem with the characteristics of good spectrum, low complexity and fast acquisition, a full digitizationGMSKmodem scheme was proposed. Based on LUT method, the generation of GMSK signals has better spectrum characteristicand easy to realize. In receive terminal, a non-coherent digitized GMSKreceiver with fast signal detection and symbol timing acquisitionalgorithm was presented. Double sliding windows was used to conquer the influence of communication channel gain on the detection algorithm and realized within 6 symbols with accuracy. Additionally, in order to reduce the complexity of the receiver, the received signals are demodulated sample by sample in advance and then decided with the estimated symbol timing. The symbol timing acquisition algorithm proposed is realized based on a preamble sequence rapidly within only 8 symbols. Simulation results and integrated FPGA realizationprove its feasibility and superiority.

An optimal scheduling strategy for cooling, heating and power (CCHP) joint-power-supply system is proposed to improve energy utilization and minimize costs in this paper. Firstly, the mathematical model of CCHP system is established. Particle swarm optimization (PSO) is used to optimize the regularization coefficient C and the kernel parameter λ which can affect the prediction accuracy of KELM(PSO-KELM). Then PV generation and load prediction model are established by PSO-KELM. In order to jump out of local optimal solution, Cauchy variation is introduced in SFLA local update, and adaptive mutation operation is carried out on SFLA individuals. The predictions of PV generation and load power by PSO-KELM are imported into the objective function, and the microgrid dispatching model is solved by the improved SFLA algorithm. Compared with the traditional GA-KELM and KELM, PSO-KELM has faster convergence and prediction accuracy. Compared with the power supply division, the operation cost of the power grid is reduced by the proposed optimization dispatching strategy of CCHP micro-grid.