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1.
基于数字图像的玉米叶面积测量方法研究   总被引:7,自引:2,他引:5  
【研究目的】以数字图像处理技术为基础,采用数码相机获取数字图像,建立使用Visual C++6.0开发的图像处理软件进行玉米叶面积测量的方法。【方法】首先,用数码相机拍摄挂在墙上粘贴着玉米叶片的参照白板来获得数字图像。然后提取图像的蓝色分量,利用中值滤波、膨胀、腐蚀等方法去除图像噪声,最大类间方差法自动阈值分割目标。接着进行区域标记与区域像素数统计,区域像素数结合图像分辨率就可以获得玉米叶片的实际面积。【结果】与直尺法所测结果具有很好的相关性,且比直尺法更精确,【结论】此种拍摄方法避免了几何畸变的产生。蓝色分量图像中目标和背景的灰度差异最大,便于分割。  相似文献   

2.
用数字图像技术研究了冬小麦冠层生物量的垂直分布。表明用一行小麦图像比多行小麦图像估测小麦生物量能更好地满足线性回归关系,估测效果更佳,以此为基础进一步研究了分层像素数估测小麦冠层分层现存生物量和有效生物量的方法。利用分层绿色像素数(LGPN)指标定性分析了不同栽培模式下冬小麦群体有效生物量的垂直分布和动态变化,并确定了基于图像特征的可用于定量分析的小麦群体垂直分布指数(I)。  相似文献   

3.
Nuclear magnetic resonance (NMR) images were taken of freshly harvested fruit (Lycopersicon esculentum cv. Castlemart). Measurements were also made of the stage of repeness, rate of carbon dioxide and ethylene production, lycopene and chlorophyll content, density of the pericarp wall, and consistency of the locular tissue. An NMR image at 256 × 256 pixel per image and 16 levels of intensity per pixel clearly showed many structural details of the fruit. Increased intensity was associated with liquefaction of the placental tissue during ripening, while grainines of the pericarp wall was associated with a decrease in wall density. In vivo NMR imaging of mature-green fruit produced images in which differences in maturity could be seen. The long required to produce an image and the cost of operation currently precludes the use of NMR imaging to sort mature-green tomato fruit.  相似文献   

4.
Aiming at the questions of raceway section two dimension temperature distribution from two dimensional image accumulated by three dimensional radiation space and three dimensional temperature reconstruction error caused by limited charge coupled device (CCD) sensors for a sudden spread combustion chamber, the two dimension rectangle interpolation virtual CCD sensor installation algorithm is provided as a new technology for solving the difficulties of installing more CCD sensors and filtered back projection reconstruction error caused by limited projection numbers. The radiation intensity projection data got from flame image collected from the installed CCD sensors and computed virtual CCD sensors is interpolated for filtered back projection to computer intensity distribution and calibrated bi color method is used to calculation temperature in raceway depth direction. The results of experiments on a mini type coal gas furnace and practice test showed that the algorithm is accurate and credible and realized the on line monitoring for sudden spread combustion chamber raceway depth direction. At the same time, the useful information is provided for further studying combustion working state for the sudden spread combustion chamber.  相似文献   

5.
农业大棚温度自动记录仪设计   总被引:1,自引:1,他引:0  
王梅娟 《中国农学通报》2012,28(26):178-182
为了便于实时监控农业大棚温度的变化,设计了测定农业大棚小环境的温度自动记录仪。该记录仪采用数字温度传感器、单片机、显示器和I2C器件。软件设计主要包括:温度信号的采集、温度数据的储存与读取、汉字与采集结果的混合显示3个模块;通过对系统的设计进行Proteus仿真,结果表明系统的软硬件设计正确。  相似文献   

6.
The monitoring and assessment scheme of the Caiyuanba Yangtze Bridge is present by sensitivity analysis. The mechanics character of the six ties is studied by numerical simulation, and then the sensor location and selection are discussed considering the technique of sensor and construction situation. The trend of the displacement at the sensor location is analyzed according to different damage level of ties, the pattern associating with several displacements which are sensitive to damage at ties is bring forward to improve assessment reliability. The result can assist implement of structural health monitoring system to the same type as this bridge.  相似文献   

7.
随着科学技术的发展,农业的发展越来越趋于信息化、现代化,智慧农业是未来农业发展的必然趋势。温室控制系统是智慧设施农业的核心,是实现设施农业规模化发展、集约化生产的关键。本研究综述了温室控制相关研究进展,以期在今后的研究中起到一定的作用。温室控制系统自20世纪70年代发展至今越来越成熟,本研究对比了温室控制系统的控制算法、主控芯片、各种传感器,通过对近些年来包括控制系统在内的感知层、传输层和应用层等组成部分综述,并介绍了市面上比较主流的传感器、网络传输技术以及主控芯片,旨在为温室控制系统的设计提供一种可选择的方案,并对温室设施农业中存在的问题和未来的发展方向进行了分析和展望。  相似文献   

8.
Aiming at the drawbacks of the current detecting methods, a nondestructive examination system design for bridge cables based on high speed digital signal processors chip DM642 is presented, and the hardware platform of the system is built. This examination system mainly consists of four parts: the image defaults acquisition part, DM642 hardware platform, creeping part and defaults locating equipment. The designed system is tested on the hardware platform based on digital image processing algorithm. The experimental results show that the detecting system has the advantages of high stability and reliability, real time, mass storage, and nondestructive examination, etc. This system uses high technology and has significant meaning on detecting the current bridge cables health, furthermore, this method can be used in other examination fields.  相似文献   

9.
为了观测降水数据的准确性,选取了南通市4个台站2018年4月—10月份的DCS1型称重式降水传感器和SL3-1型翻斗雨量传感器观测的降水数据,分析两者观测的日降水量和降水总量等方面的差异。结果显示:在选取的观测样本中,以人工观测的降雨日数为参考,称重传感器的平均一致率为91.2%;以翻斗传感器观测的降雨日为参考,称重传感器的一致率为94.5%。称重传感器观测的累积降水量与翻斗传感器观测的累积降水量相对平均误差为-1.55%,符合中国气象局规定的相对误差不超过±4%的规范要求。在分析日降水量方面,发现称重传感器比翻斗传感器观测量平均偏小0.29 mm;有明显性降水时,两者在日降水量等级判别上基本一致。称重传感器观测的数据小于翻斗传感器观测的数据概率要高,两种传感器观测的差值分布较为一致。称重传感器在捕捉微量降水的能力不比翻斗传感器差,甚至更好。称重传感器观测的日降水量与翻斗传感器观测的日降水量相关系数为0.99826,达到0.01显著相关的水平。  相似文献   

10.
针对内蒙古自治区生态观测需求,特别是草地生态系统观测需求,选取牧草观测为研究内容,提出基于嵌入式技术和并行计算技术的实时远程可控可视的牧草观测自动化技术思路。采用特征像素图像识别方法,实现牧草覆盖度的自动测量、牧草的发育期图像自动识别。利用摄影测量技术结合图像处理技术获得像高转物高变换算法,实现层高与株高的自动测量。结合现代电子技术以及DSP技术、图像处理技术设计了牧草自动观测智能传感器,传感器在观测前端完成图像采集、处理与模式识别后,再将处理后的结果通过网络传向服务器端,可通过智能手机或PC访问服务器远程查看观测数据,实现牧草覆盖度、层(株)高以及牧草生长期的自动观测。测试结果表明,图像处理与实测覆盖度数值显著相关检验R0.05>0.90,与实测株高数值显著相关检验R0.05>0.85。相对于在后端PC系统进行图像处理,不但可以提高观测系统的数据运算处理速度,而且鲁棒性好,同时能够大大减轻数据传输压力,适合对体积、功耗、工作环境及稳定性要求极高的场合。  相似文献   

11.
粮仓中使用的各种温度传感器的分析与比较   总被引:1,自引:0,他引:1  
梁勇 《粮食储藏》2007,36(6):44-47
对在粮仓测温中使用的各种温度传感器做了一个比较全面的分析和比较.传统的温度传感器需要比较复杂的信号处理电路,而集成化温度传感器的外围电路非常简单,性能也是传统温度传感器所无法比拟的.粮仓测温的特点是所需要的传感器的数量大、传输线长和监测时间长.温度传感器的选择需要综合多种因素进行考虑.目前,还没有一种温度传感器可以完全替代其它的温度传感器.  相似文献   

12.
概述了在温室环境控制系统的现状,详细阐述了各个方向的发展过程、现有传感器布置方式及发展趋势,指出现有的温室环境控制系统信息获取准确性的不足,提出需要优化布置温室内的传感器,使获得的信息能准确地反映温室内的状况;需要综合利用来自多传感器的信息,提高测控系统的性能,提高温室环境的控制效果和减少调控所需的能源消耗的问题,提出在设计温室环境控制系统时,应考虑传感器的布置方式和数据处理的方法。  相似文献   

13.
In our experiment digital image processing is used to predict characteristics in a winter oilseed rape canopy. A large series of images was taken in 2002–2003 in close intervals from a measuring area of 1 m2. These images were automatically evaluated by a self‐written computer program analysing the red/green/blue colour channels of each pixel. The number of determined green pixels was then related to the total pixel count of the image. Image evaluation helped to determine canopy structure by digital image analysis subjected to several applications, i.e. soil coverage, leaf area index (LAI), dynamics of plant number during vegetative developmental stages including entire winter season. Furthermore, number of plants per m2 and position of each plant were determined by image analysis. Results show that all parameters are dynamic during the vegetative developmental stages (germination–beginning of flowering) mainly depending on temperature. During the vegetative developmental stages number of plants varied. Emergence lasted 30 days resulting in large differences in growth and development of individual plants. During winter number of plants decreased due to longer phases of frost. Plant growth indicated by dynamics of LAI alternated with phases of cessation due to low temperatures above zero or frost. Reductions in soil coverage and LAI clearly started at daily mean temperatures below 5 °C. After the analysis, differences in LAI as well as changes in number of plants during the early phase crop development can serve (i) as input parameters to growth models, (ii) to improve canopy reflectance measurements by separating spectral signatures of soil and canopy and (iii) to determine and explain heterogeneities within the canopy.  相似文献   

14.
为实现鸡舍内温湿度的远程监控,便于适时调整舍内的温湿度。基于无线单片机CC1110、数字温度传感器DS18B20、湿敏电容湿度传感器KSC-6V和微型液晶显示器1602LCD,设计了鸡舍环境温湿度微型无线监测仪的硬件电路及其C语言驱动程序。该监测仪精度高、成本低廉、结构简单、安装操作方便,且信号传输距离远,能够满足鸡生长过程中对温湿度监测的要求,具有很好的应用价值。  相似文献   

15.
为了给森林资源监测中无人机遥感的应用研究提供依据,归纳了无人机遥感用于森林资源监测的技术流程,总结了在森林资源监测中常用的传感器类型,分析了无人机遥感在森林病虫害监测、林分树高测定、森林冠层结构与属性测定、树种组成识别、森林生物量测定中的应用和表现。得出通过无人机遥感搭载各种类型的传感器来收集森林信息,将是未来森林资源监测的一个重要方向;无人机遥感数字化、信息化、自动化提取森林结构参数将是无人机遥感用于森林资源监测中的发展趋势;此外,无人机遥感搭载多样化传感器以及传感器的小型化、商业化将进一步促进森林资源的精确监测。  相似文献   

16.
Synthetic aperture radar (SAR) raw signal generation and SAR image simulation of typical targets are very significant for the validation of SAR imaging algorithms, the interpretation of SAR images, and automatic target recognition of SAR images. Based on analysis of the existing SAR raw signal generation and SAR image simulation methods, a new method for SAR raw signal generation and SAR image simulation is proposed. This method combined the curved surface pixel method (CSPM) and the two dimensional FFT (2DFFT) based SAR raw signal generation model. CSPM is used to calculate the target reflectivity, while the 2DFFT method is employed to obtain the raw signal. The simulations are carried out, and the effectiveness of this method is validated by the results of simulating some typical targets.  相似文献   

17.
18.
In wireless sensor networks that consist of a large number of low-power sensors.Because the sensor's energy is limited,one of the main design is to obtain long system lifetime.The authors firstly analyse LEACH and LEACH-C clustering routing for wireless sensor networks.Aimming at their shortcoming,they present a new routing LEACH-NEW.This routing uses multi ho Pinstead of one hop.At last,they use NS2 to simulate them.Simulation show results that new routing exhibits noticeably longer system lifetime than rouing LEACH and LEACH-C.  相似文献   

19.
应用电子鼻技术对粳稻谷中霉菌定量分析   总被引:1,自引:0,他引:1  
用德国Airsense公司生产的PEN3型便携式电子鼻系统分析检测不同储藏条件下粳稻谷的挥发性物质,结果表明:通过PCA分析,不同储藏条件的粳稻谷样品可以很好的被区分;利用Loadings分析传感器贡献率挑选W1S、W2S、W5S、W3S、W1W、W2W作为新传感器阵列,对15℃、25℃、30℃条件下的传感器响应值进行...  相似文献   

20.
土壤水分快速测量传感器研究及应用进展   总被引:2,自引:1,他引:1  
土壤水分的测量直接关系到作物的灌溉,进而影响到作物的产量,是一项长期且艰巨的任务。总结了目前市场上3种主流的基于介电原理的土壤水分传感器,阐述了它们的测量原理、标定方法、影响因素以及性能情况,分析了使用过程中可能出现的一些问题,并对其未来的发展方向进行了展望,旨在为农技、水利部门在选用该类型的土壤水分传感器产品和测量土壤水分的过程中提供一定的参考和借鉴。  相似文献   

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