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1.
猕猴桃硬度近红外漫反射光谱无损检测   总被引:6,自引:1,他引:6  
为了给猕猴桃成熟度判定提供一种无损检测手段,进行了基于近红外漫反射光谱定量分析技术检测冷藏期间猕猴桃硬度的试验研究。采用偏最小二乘法对“华优”猕猴桃的近红外光谱进行了分析,并且比较和讨论了4种光谱预处理方法的建模结果。试验结果表明,在全谱范围内,一阶微分光谱所建模型效果最佳,其校正相关系数为0.963,预测相关系数为0.852。  相似文献   

2.
近红外漫反射检测梨可溶性固形物SSC和硬度的研究   总被引:1,自引:0,他引:1  
采用近红外漫反射光谱检测梨可溶性固形物(SSC)和硬度.采集梨的近红外漫反射光谱,光谱经梨的吸光度原始光谱、一阶微分和二阶微分预处理,分别采用多元线性回归、主成分回归和偏最小二乘法,建立了梨可溶性固形物(SSC)和硬度的定量预测数学模型.结果表明采用一阶微分结合偏最小二乘法的预测效果最好,可溶性固形物(SSC)和硬度定量数学校正模型的相关系数分别为0.9285和0.8478,均方根误差分别为0.4364°Birx和1.227.近红外漫反射光谱作为一种无损的检测方法用于评价梨可溶性同形物(SSC)和硬度是可行的.  相似文献   

3.
分别针对中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)2个日粮纤维水平评价指标,开展适用于不同饲料原料的NDF和ADF近红外综合预测方法研究。收集包括玉米干酒糟及其可溶物、大豆皮、小麦麸、苜蓿草颗粒、喷浆玉米皮和甜菜粕共6种饲料原料,共计327个样品。按照Van Soest滤袋法测定每个样品的NDF和ADF,获取参考值,并进行统计学分析。利用傅里叶变换近红外光谱仪采集样品的近红外漫反射光谱。选择偏最小二乘法,结合导数处理、多元散射校正和变量标准化等不同的光谱预处理方法,构建定标模型。结果表明:6种饲料原料的NDF和ADF分布范围分别在21.20%~65.28%和6.40%~48.31%,洗涤纤维含量覆盖范围广。NDF近红外快速预测模型:最优预处理方法为二阶导数,模型验证集决定系数为0.963,预测标准误差为1.82,相对分析误差为5.2。ADF近红外快速预测模型:最优预处理方法为一阶导数结合变量标准化,验证集决定系数为0.985,预测标准误差为1. 63,相对分析误差为8.23。本研究表明基于近红外光谱这种无损分析技术,可构建适用于多种纤维类饲料原料的日粮纤维水平快速预测模型,该方法可为饲料工厂快速检测洗涤纤维、精细调控饲料中纤维水平提供有效的技术保障。  相似文献   

4.
近红外光谱检测梨果硬度研究   总被引:1,自引:0,他引:1  
应用近红外漫反射无损检测梨果硬度。采集240个梨样品的光谱数据,150个梨样品数据用于建模集来建立模型,另外90个样品数据用于预测集,评价模型的性能。采集完整梨果的近红外漫反射光谱(350~1 800nm),为简化模型,原始光谱经小波算法去除噪声,然后采用CARS算法,波长由最初的1 451个降低为58个,采用偏最小二乘回归建立梨果硬度的定量预测数学模型。研究发现,CARS算法在简化模型同时,模型的预测评价指标优于原始光谱建模的模型,硬度定量预测数学模型的决定系数(Rp2)为0.66,均方根误差(RMSEP)为1.66。近红外漫反射光谱作为一种无损的检测方法,可用于评价梨果的硬度。  相似文献   

5.
基于模拟退火波长优化的草莓坚实度近红外光谱检测   总被引:1,自引:0,他引:1  
为提高近红外光谱技术检测草莓坚实度模型的精度和鲁棒性,研究了一种基于模拟退火算法的波长优选方法,并找到一种与该算法配套的光谱预处理方法.利用光谱仪和物性仪分别采集草莓样品近红外漫反射光谱和坚实度数据,并采用标准正交变换、多元散射校正、一阶导数、二阶导数等方法对原始光谱进行预处理;最后,利用模拟退火算法优选与草莓坚实度高度相关的波数点变量,结合偏最小二乘法建立草莓坚实度预测模型.结果表明:经过标准正交变换预处理后,采用模拟退火算法优选出24个波数点,在主成分数为5时,建立的偏最小二乘模型具有最佳预测效果,模型校正集样本相关系数rc为0.934 2,校正均方根误差为0.665 N/cm2;预测样本相关系数rp为0.919 7,预测均方根误差为0.673 N/cm2.研究表明:模拟退火算法可以提高近红外模型预测草莓坚实度的精度和鲁棒性,并降低预测模型复杂度.  相似文献   

6.
为实现“贵长”猕猴桃成熟度的快速无损检测,提出高光谱成像结合模式识别建立识别模型的检测方法。首先利用可见/近红外(390~1 030 nm)高光谱成像系统采集不同成熟阶段猕猴桃样本的高光谱图像,并获取整个样本区域的光谱反射率。然后对比3种光谱预处理方法:二阶导数、标准正态变换以及多元散射校正对原始光谱的预处理效果。最后分析偏最小二乘判别分析(PLS-DA)和简化的K最近邻(SKNN)模式识别方法对猕猴桃成熟度的识别性能。结果表明:相对于标准正态变换和多元散射校正两种光谱预处理方法,二阶导数预处理方法对原始光谱的预处理效果相对较好。另外,PLS-DA识别模型对猕猴桃成熟度的识别性能要优于SKNN识别模型,其正确识别率达到100%。表明采用高光谱成像技术结合模式识别方法判别“贵长”猕猴桃成熟度是可行的。  相似文献   

7.
为提高近红外光谱技术检测草莓坚实度模型的精度和鲁棒性,研究了一种基于模拟退火算法的波长优选方法,并找到一种与该算法配套的光谱预处理方法。利用光谱仪和物性仪分别采集草莓样品近红外漫反射光谱和坚实度数据,并采用标准正交变换、多元散射校正、一阶导数、二阶导数等方法对原始光谱进行预处理;最后,利用模拟退火算法优选与草莓坚实度高度相关的波数点变量,结合偏最小二乘法建立草莓坚实度预测模型。结果表明:经过标准正交变换预处理后,采用模拟退火算法优选出24个波数点,在主成分数为5时,建立的偏最小二乘模型具有最佳预测效果,模型校正集样本相关系数rc为0.9342,校正均方根误差为0.665N/cm2;预测样本相关系数rp为0.9197,预测均方根误差为0.673N/cm2。研究表明:模拟退火算法可以提高近红外模型预测草莓坚实度的精度和鲁棒性,并降低预测模型复杂度。  相似文献   

8.
苹果硬度的傅里叶变换近红外光谱无损检测   总被引:3,自引:1,他引:3  
利用傅里叶变换近红外光谱技术探讨快速无损检测苹果硬度方法的可行性.通过解析苹果样品的近红外光谱图,用一阶导数、多元散射校正和矢量归一等方法进行预处理,再用偏最小二乘法建立模型.结果表明,多元散射校正能够有效消除光谱基线平移和偏移现象, 提高原光谱的信噪比,选取有效信息波长范围为1408~2355nm.偏最小二乘法结合多元散射校正所建模型的预测效果最好,模型的决定系数R2为0.9852,内部交叉验证均方根差RMSECV和预测标准偏差RMSEP分别为0.0398kg/cm2和0.0166kg/cm2.进一步通过剔除异常值优化模型,并验证检验组的25个样品,模型的R2为0.9908,RMSEP为0.0147kg/cm2.结果表明:建立的模型可靠,预测效果好,能满足苹果硬度快速检测的要求.  相似文献   

9.
运用近红外漫反射技术检测苹果内部品质   总被引:3,自引:0,他引:3  
为了建立山东烟台富士苹果糖度和硬度的近红外光谱测定法,本实验应用光纤漫反射近红外光谱检测技术快速定量分析苹果的糖分含量和硬度。使用偏最小二乘法建立预测模型,样品糖分预测值和实测值之间的相关系数为0.97210,校正标准差(RMSEC)为0.363;样品硬度预测值和实测值的相关系数为0.95452,校正标准差(RMSEC)为0.594。通过本次试验研究表明,近红外光谱测定法能准确地对富士苹果糖分含量和硬度进行无损快速定量分析。  相似文献   

10.
以醋糟有机基质为研究对象,采用便携式可见/近红外光谱仪采集了不同含水率基质样品(69个)的漫反射光谱,通过选择不同的光谱预处理方法并确定其主成分数,建立了基于偏最小二乘法(PLS)的醋糟基质含水率定量分析模型.结果表明,以滑动平均滤波(MAF)和一阶微分(FD)相结合作为原始光谱的预处理方法所建立的模型(主成分数为5)对基质含水率的检测效果较好,其校正模型和预测模型决定系数分别为0.9930和0.9901,校正均方根误差(RMSEC)和预测均方根误差(RMSEP)分别为0.0676和0.071 5.因此,可见/近红外光谱技术可以作为醋糟有机基质含水率快速检测的一种可靠方法.  相似文献   

11.
Overland water and salt flows in a set of rice paddies   总被引:1,自引:0,他引:1  
Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m−1) and an infiltration rate of 5.8 mm day−1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day−1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day−1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.  相似文献   

12.
瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。  相似文献   

13.
对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明:该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。  相似文献   

14.
对《种子法》存在问题的探讨   总被引:1,自引:0,他引:1  
《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。  相似文献   

15.
About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.  相似文献   

16.
赵异 《湖南农机》2007,(3):31-32
在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。  相似文献   

17.
A European irrigation map for spatially distributed agricultural modelling   总被引:1,自引:0,他引:1  
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.  相似文献   

18.
在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。  相似文献   

19.
农村信息化服务的现状及建设措施   总被引:2,自引:0,他引:2  
分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。  相似文献   

20.
车辆ABS控制算法的研究及探讨   总被引:1,自引:0,他引:1  
对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。  相似文献   

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