大学毕业论文—基于单片机的温度与湿度解耦控制系统设计外文翻译.doc

外文文献 Abstract Climate conditions control emphases of automatic control greenhouses introduced from abroad are different from these in home and the introducing and production cost of them is so high ,so it is difficult to popularize and use cosmically .At present, in greenhouses designed and built in home itself，the degree of environment control and modern management of most of them is so low ,so they cannot satisfy crops demand for high production and planting all the year; some can only carry out control on partial environment factors without considering mutual affect and coupling of them in the process of control; some still need manual control;so these factors greatly restrict exertion of economic benefit of greenhouses .Changing traditional modes of control; practicing computer monitoring and establishing greenhouse automatic monitoring system accord with the situation of China have important meaning for quickening modern degree of greenhouse production in our country and increasing benefit of greenhouses. Based on summarizing formers researches, the paper analyzes environmental parameters，the integrative control property of greenhouse systems and the control process which is a nonlinear, delay and complicated system; Based on analyzing modes of current greenhouse monitoring systems and properties of single-chip microcomputers, a practical automatic monitoring system for greenhouse environment is designed which can realize the monitoring of every parameter in greenhouse environment by synthetically using sensor technology, fuzzy control theory, communication technology and microcomputer technology The system hardware is composed of two parts: a lower-level and a higher-level computer. The higher-level computer is a PC microcomputer which is the headquarter of the system and finishes the unified management and control of a greenhouse by way of COM port RS-232 connecting with the lower-level computer. In monitoring environment,