| In recent years,with the rapid development of computer technology,how to make good use of computer technology in traditional agriculture has become an important issue of domestic and international research.China is a big country of rice planting.In the traditional process of the leaf area statistics and the rice planting spacing optimization,researchers mainly use manual collection and field experiment.The canopy leaf area,leaf area index,the suitable planting spacing and other related parameters are able to be obtained.Thus,this work is tedious and time-consuming,and we can’t get the experiment results quickly and effectively.By using the computer technology,we can simulate the physiological growth processes of a rice plant with a virtual model,and results of the measurement and the optimization can be obtained quickly and intuitively.Since rice is various and complex,there is still lacking of the reaserch on rice leaf area statistics and optimization of planting spacing.In this paper,we calculate the leaf area of rice canopy and optimize the planting spacing of rice by having constructed a virtual rice model in the virtual environment to provide a reference for a real rice plant in the field.The main works are given as follows:1.A virtual rice model is established.Firstly,we obtain the relevant parameters of the leaf through field experiment,and construct a leaf model based on the experimental data.Secondly,we construct stems of the rice plant according to the growth position of the stem in the ground,the length and the width of the stem,the inclination angle and other parameters.Finally,we construct the virtual rice model according to the topological relation between organs.2.A statistical algorithm for leaf area based on virtual rice model is proposed.Firstly,we ascertain the position of rice leaf in space according to the parameter information.Secondly,we calculate the area of the leaf in different height range according to the contour curve equation and the space position of the blade.Finally,we traverse all the leaves of the virtual rice model and calculate the total leaf area in different heights of the rice canopy.The algorithm can also calculate the total leaf area of a single rice plant.3.A spacing optimization method based on genetic algorithm is studied.Firstly,we construct the scene of the virtual rice model which combines the rice structure and the rice physiological function.Secondly,we construct a genetic algorithm.The planting spacing and row spacing are made as the genetic factors.The chromosomes of the genetic algorithm are encoded with binary method.The photosynthetic yield of the unit planting area is made as the fitness value.The evolutionary process which is based on roulette wheel selection,elite selection,alternative crossover and competition is implemented.finally,we obtain the high yield planting plan in the process of the optimization algebraic.4.A method of calculating rice sealing stage time based on virtual rice model is proposed.First of all,we quantify the rice sealing stage according to the concept of agricultural and rice leaf calculation method proposed in this paper.Then,we calculate the rice sealing stage time of the rice with current planting spacing based on the model of virtual rice.5.The rice plant spacing optimization system is built.The system is developed in the Qt Creator5.0 development environment,using C++ programming language and OpenGL rendering engine programming.By using it,the visual simulation of rice plants can be carried out,the plant canopy leaf area calculation and the planting spacing can be optimized and completed respectively.In this paper,a preliminary study about virtual rice modeling,statistics of rice leaf area,field planting spacing optimization and rice sealing stage time calculation are contructed.The virtual model is established and the optimization algorithm is realized by us.This study provides a new idea for the combination of computer technology and traditional agriculture,which can provide assistant decision support for the optimization of rice canopy structure and the rationalization of rice planting density. |
