共查询到20条相似文献，搜索用时 125 毫秒
1.
基于CAN总线的智能温室分布式监控系统 总被引：1，自引：0，他引：1
系统采用分布式网络结构,主要分为上位机和下位机两部分.上位机主要完成了CAN通讯适配器的设计以及智能温室人机界面的软件设计;下位机以MC68HC912BC32单片机为控制核心,配以一总线温度传感器和湿度传感器组成监控器,利用CAN总线实现对温室大棚内多点的温湿度进行智能监控.实用证明:智能温室分布式监控系统具有性能稳定、经济、方便以及通用性强等特点. 相似文献
2.
3.
4.
介绍了一项自主研发的智能节水温室系统,主要论述上位机的设计开发。上位机通过RS232串口发送控制指令到下位机中,采集下位机控制的现场传感器数据,并通过串口将数据送到上位机。上位机可以设定土壤的温、湿度等墒情指标的阈值,下位机根据上位机预置阈值来控制卷帘、通风和水泵等设备的相应操作,实现了精准灌溉、节水、节能。 相似文献
5.
6.
《中国农机化学报》2015,(1)
针对温室管理智能化的需要,提出了一种基于无线数据传输的温室环境参数监控系统。该系统以MSP430F169作为微控制器,通过数字温湿度传感器DHT11、土壤温湿度传感器SHT10P、光强数字转换芯片TSL2561和CO2气体传感器MG811检测温室环境中的空气温湿度、土壤温湿度、光照强度及CO2含量,以n RF24L01+作为射频无线通信模块实现下位机和上位机之间的数据通信,以TC35i作为GSM无线通信模块实现上位机和监控终端之间的数据通信。用户可以通过上位机或监控终端对温室环境参数进行检测和控制,使温室内环境参数控制在所希望的水平上,实现温室环境参数的智能化控制。 相似文献
7.
8.
9.
10.
基于通信技术实现了牡丹温室中3个重要参数(温度、湿度、光照)的测量与控制。该系统整体采用主从结构:上位机(PC机)系统和下位机(单片机)系统。在上位机系统中,用VB 6.0开发了冬季牡丹培育过程的专家系统,查询和修改方便;下位机系统包括单片机、传感器和控制执行机构。该系统已在菏泽调试成功,较大幅度地提高了牡丹培育的质量,增加了经济效益,具有较高的实用性和推广价值。 相似文献
11.
12.
13.
14.
15.
《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
16.
感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
17.
18.
从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性，认为在缺水不可避免的情况下，对供水进行优化调度可以减小缺水带来的损失，产生较好的减灾效益，特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性，提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献
19.
20.
The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献