水肥一体化是将灌溉与施肥相结合的一项综合技术,具有省肥、省水、省工、环保、高产、高效的突出优点,目前生产型日光温室的水肥一体化灌溉施肥和灌溉作业,多数依靠人工经验完成,灌溉的及时性、科学性及智控化程度不高。本研究应用STM3...水肥一体化是将灌溉与施肥相结合的一项综合技术,具有省肥、省水、省工、环保、高产、高效的突出优点,目前生产型日光温室的水肥一体化灌溉施肥和灌溉作业,多数依靠人工经验完成,灌溉的及时性、科学性及智控化程度不高。本研究应用STM32嵌入式系统,实时采集埋入土壤中的上、中、下3个深度的湿度传感器的数据,根据不同作物预定的施肥、灌溉策略,自动控制完成温室水肥一体化灌溉作业。该系统同时具有远程监控功能,采用全球移动通信(global system for mobile,GSM)模块给用户提供远距离短消息服务,用户不仅可以通过短信对温室灌溉、光照、通风的远程智能监测,同时可远程控制系统作业的启停,以此实现温室环境的自动化管理,达到远程施肥与节水灌溉的目的。展开更多
介绍了两种新的人造地震动的加速度反应谱拟合方法:其一是时域叠加法.该方法通过在时程上叠加一谐波时程来调整某一反应谱控制点的值.其特点是交叉干扰小,计算量小且能兼顾强度包线的要求:其二是反应谱整体逼近法.其特点是在调整某一由...介绍了两种新的人造地震动的加速度反应谱拟合方法:其一是时域叠加法.该方法通过在时程上叠加一谐波时程来调整某一反应谱控制点的值.其特点是交叉干扰小,计算量小且能兼顾强度包线的要求:其二是反应谱整体逼近法.其特点是在调整某一由幅值谱AR及其相位谱ψk（k=0,1,2,…,n）决定的时程Ra（t）时,用反应谱与目标谱在各个控制点上相对误差Ej（j=1,2,3,…,M）的均方根值Vr=（sum form j=1 to m(Ej2/M）l2是否减小来判定任一幅值谱Ak调整的方向.本文指出,由于Ej及Vr均是Ak及ψk的函数,所以,合成加速度时程中的反应谱拟合问题可变成寻找V1极小点的数学问题.时域叠加法受最高截止频率的限制,不适用于反应谱高频部分的拟合.反应谱整体逼近法受FFT算法频率分布特征的限制,使反应谱低频部分的控制点密度不能太大.大量的试算结果表明,以上两种方法相互补充,可取得良好的拟合效果.文中还指出,由于有了较好的反应谱拟合方法,可在反应谱拟合的同时,对加速度时程的峰值加速度及峰值速度进行拟合.展开更多
The integration of water and fertilizer is a comprehensive technology combined irrigation and fertilizer, which has outstanding advantages of saving fertilizer, saving water, saving labor, protecting environment, high...The integration of water and fertilizer is a comprehensive technology combined irrigation and fertilizer, which has outstanding advantages of saving fertilizer, saving water, saving labor, protecting environment, high yield and high efficiency. Currently, most of the water and fertilizer integrated irrigation and fertilization and irrigation operation in the production-based greenhouse is achieved relying on artificial experience, which is hard to achieve timely, scientific and intelligent irrigation. In this study, the application of STM32 embedded system realized the real-time collection of the data from the humidity sensors buried in top, middle and low depth of soil, and water and fertilizer integrated irrigation work was completed in the greenhouse through automatic control according to the predetermined fertilization and irrigation strategies for different crops. Moreover, the system had remote monitoring function, which used the global system for mobile （GSM） module to provide users with remote short message services, and therefore, the users could not only achieve the remote intelligent monitoring on the irrigation, light, ventilation of the greenhouse through short messages, but also could start and stop the remote control system operation, so as to realize the automatic management of the greenhouse environment, achieving the purpose of remote fertilization and water-saving irrigation.展开更多
文摘水肥一体化是将灌溉与施肥相结合的一项综合技术,具有省肥、省水、省工、环保、高产、高效的突出优点,目前生产型日光温室的水肥一体化灌溉施肥和灌溉作业,多数依靠人工经验完成,灌溉的及时性、科学性及智控化程度不高。本研究应用STM32嵌入式系统,实时采集埋入土壤中的上、中、下3个深度的湿度传感器的数据,根据不同作物预定的施肥、灌溉策略,自动控制完成温室水肥一体化灌溉作业。该系统同时具有远程监控功能,采用全球移动通信(global system for mobile,GSM)模块给用户提供远距离短消息服务,用户不仅可以通过短信对温室灌溉、光照、通风的远程智能监测,同时可远程控制系统作业的启停,以此实现温室环境的自动化管理,达到远程施肥与节水灌溉的目的。
文摘介绍了两种新的人造地震动的加速度反应谱拟合方法:其一是时域叠加法.该方法通过在时程上叠加一谐波时程来调整某一反应谱控制点的值.其特点是交叉干扰小,计算量小且能兼顾强度包线的要求:其二是反应谱整体逼近法.其特点是在调整某一由幅值谱AR及其相位谱ψk（k=0,1,2,…,n）决定的时程Ra（t）时,用反应谱与目标谱在各个控制点上相对误差Ej（j=1,2,3,…,M）的均方根值Vr=（sum form j=1 to m(Ej2/M）l2是否减小来判定任一幅值谱Ak调整的方向.本文指出,由于Ej及Vr均是Ak及ψk的函数,所以,合成加速度时程中的反应谱拟合问题可变成寻找V1极小点的数学问题.时域叠加法受最高截止频率的限制,不适用于反应谱高频部分的拟合.反应谱整体逼近法受FFT算法频率分布特征的限制,使反应谱低频部分的控制点密度不能太大.大量的试算结果表明,以上两种方法相互补充,可取得良好的拟合效果.文中还指出,由于有了较好的反应谱拟合方法,可在反应谱拟合的同时,对加速度时程的峰值加速度及峰值速度进行拟合.
基金Supported by the Scientific Research Plan of the Education Department of Jilin Province(2014322)~~
文摘The integration of water and fertilizer is a comprehensive technology combined irrigation and fertilizer, which has outstanding advantages of saving fertilizer, saving water, saving labor, protecting environment, high yield and high efficiency. Currently, most of the water and fertilizer integrated irrigation and fertilization and irrigation operation in the production-based greenhouse is achieved relying on artificial experience, which is hard to achieve timely, scientific and intelligent irrigation. In this study, the application of STM32 embedded system realized the real-time collection of the data from the humidity sensors buried in top, middle and low depth of soil, and water and fertilizer integrated irrigation work was completed in the greenhouse through automatic control according to the predetermined fertilization and irrigation strategies for different crops. Moreover, the system had remote monitoring function, which used the global system for mobile （GSM） module to provide users with remote short message services, and therefore, the users could not only achieve the remote intelligent monitoring on the irrigation, light, ventilation of the greenhouse through short messages, but also could start and stop the remote control system operation, so as to realize the automatic management of the greenhouse environment, achieving the purpose of remote fertilization and water-saving irrigation.
