Information Acquisition And Expert Decision System In Litchi Orchard Based On Internet Of Things

China is the great country of planting litchi.Chinese litchi cultivation area was 127.5 thousand hm2 in 1987's,but it had been 553.3 thousand hm2 in 2015;The total output of litchi was 116.8 thousand t in 1987,but it had been 2200 thousand t in 2015.A majority of the litchi orchards are still arranged with traditional artificial way in our country,like irrigation and fertilization of fruit trees,predicting pest diseases and so on are depending on artificial experience to make a decision.This kind of artificial management is so rough and less purpose,especially the traditional irrigation methods such as flooding,which cause a waste of water resources.The emergence of the Internet of things has provided strong support for the realization of orchard modernization.The application of internet of things in orchard production and management can realize the remote monitoring orchard real-time environmental information,otherwise,timely supply of water and fertilizer to fruit trees to minimize the consumption of water resources.Through the internet of things,managers can know the occurrence of pest diseases in time,in order to make preventive or treatment measures,which can greatly improve the fruit yield and quality.Considering litchi as an application object,this paper constructs the litchi orchard information acquisition and expert decision-making system based on the Internet of things,designing the system software,hardware,research and establishing multiple expert decision-making models,carring out system test in the actual litchi orchard environment as well.The main contents and achievements of this paper are as follows :Introduce the development of Internet technology and function systematicly,investigate the irrigation decision theory model of expert system,analyze the key technologies developed by experts in detail,theremore,provide theoretical basis for the construction of litchi orchard information acquisition and expert decision system,which are basing on the internet of things.Analyze the system function need s on environmental data acquisition,network topology structure,data frequency acquisition,module and remote server design and precise decision model design in detail.Introduce the overall architecture and functions of the system.And explain the workflow of the system.Investigate the information acquisition part of design system including hardware design and software programming,as a result,provide data support for the decision model of expert system.Hardware design mainly designs terminal monitoring equipment and gateway module.Especially,the design of terminal monitoring equipment includes the selection of short-distance wireless communication module,processor selection,information acquisition terminal module design,terminal control module design and routing module design.Software design is mainly three parts,first of all is the design of terminal monitoring equipment software including network mode,information acquisition terminal module software design,terminal control software design and routing module software design,etc.Then the gateway module software is designed.Finally the remote server module software is designed including working principle,data communication protocol,data interaction,function design and implementation and so on.The design of intelligent irrigation expert decision system mainly includes the database of design expert decision system including integrated databases and knowledge base.Designing expert system of fertilization and plant diseases and insect pests of decision rules,the litchi diseases and insect pests were summarized and classified,realizing every function module of expert system by software programming,Which make expert system receives real-time environmental information data of litchi orchard from information acquisition section and make intelligent decision combiling partial auxiliary facts.This paper designed the detailed testing program to test the working performance of the system in the litchi orchard,the real environment,including the test of the internet packet loss rate,the accuracy of information collecting terminal module and the irrigation decision of expert system,the decision real-time performance of expert system.Then summarize and analyze the testing data.Finally draw the testing conclusion.The test of the internet packet loss rate shows that the average packet loss rate of the total system is about 3.41%,which means that the system can work stably and the internet transmission of the system is steady and reliable.The test of information collecting terminal module accuracy indicates that the monitoring precision of the module is high enough to offer accurate decision data support for expert decision system.The test of the irrigation decision of expert system accuracy shows the irrigation decision accuracy is higher,when the expert system input is multiparameter rather than one-parameter.The test of the decision real-time performance of expert system indicates the soil moisture content of litchi trees in irrigation area is between 15.55% and 19.14%,which keeps the trees in a most suitable growing situation.As a result,the decision real-time performance of expert system is excellent and its reaction speed is quick.