基于MSCPSO混合核SVM参数优化的生菜品质检测

核函数形式的选择与核函数参数值的大小是影响支持向量机的2个关键因素,传统的支持向量机分类精度低、时效性差,为了获得高精度、高时效性的支持向量机,从影响支持向量机的核函数与核函数参数值2个关键因素着手,提出了基于变尺度混沌粒子群优化（MSCPSO）混合核SVM参数的分类器。将此分类模型用于预测生菜叶片的生育期,以及预测3个生育期的生菜叶片氮素水平,预测精度分别达到91.51%、85.38%、82.59%和81.26%。与传统的粒子群优化混合核SVM的分类器和变尺度混沌粒子群优化RBF_SVM分类器相比,提出的分类器模型分类精度高、时效性好。     

近红外光谱结合最小二乘支持向量机的脐橙叶片含水率无损检测

为了快速检测赣南脐橙果树叶片含水率,提出近红外光谱结合最小二乘支持向量机的快速检测方法。采用积分球漫反射方式采集叶片的近红外光谱,通过间隔偏最小二乘法从2 074个光谱变量中优选出345个变量作为建模的输入向量,分别建立最小二乘支持向量机和偏最小二乘校正模型。经比较,以径向基函数为核函数的最小二乘支持向量机模型预测结果最优,预测相关系数为0.942,预测均方根误差为2.7%,模型建立及预测时间为0.176s。实验结果表明近红外光谱结合最小二乘支持向量机的脐橙叶片含水率无损检测方法是可行的。     

基于OC-SVM和近红外光谱的秸秆固态发酵进程监测

利用近红外光谱技术结合一类支持向量机( OC - SVM)快速监测秸秆蛋白饲料固态发酵进程.首先获取发酵物样本在10000 ～4000cm-1波数范围内的近红外漫反射光谱并对其进行主成分分析,提取前7个主成分因子作为模型的输入变量,然后运用OC - SVM算法建立判别模型.在模型建立过程中,采用交互验证的方法优化OC - SVM模型的相关参数.实验结果表明,在相同的条件下,OC - SVM模型在处理失衡训练样本的问题上明显优于SVM模型,当训练集中目标类和非目标类样本数比为1∶8时,OC - SVM模型在验证集中的正确判别率达到85％.     

LS-SVM在径流预测中的应用

提出一种基于最小二乘支持向量机(LS-SVM)的径流预测方法。采用线性函数,多项式函数和径向基函数三种核函数,进行机器学习,经过反复计算和对比分析,建立了精度较高的径流预测模型。预测实例表明,LS-SVM模型预测的平均相对误差比支持向量机 (SVM)减少了2.4％,预测合格率为100％。LS-SVM建模速度快,适用于小样本情况并能得到全局最优解,将其用于径流预测是可行的。     

考虑直径影响的苹果霉心病透射光谱修正及检测

针对苹果霉心病近红外透射光谱信息受果实直径影响的难题,提出了一种能够修正果实直径对透射光谱影响的方法。基于透射光谱采集平台获取327个红富士苹果的可见/近红外光谱(350～1 100 nm)信息,采用电子游标卡尺获取其直径(光程)信息。以直径为80 mm健康苹果的平均光谱作为参考光谱,将327个苹果的光谱与参考光谱进行比较,结合直径信息利用公式求得透射光在果实内的衰减系数P,用衰减系数P进行透射光谱的修正。修正后光谱建立支持向量机(SVM)模型、误差反向传播神经网络(BP-ANN)模型,并与修正前原始光谱建立模型进行对比。实验结果表明,应用此光谱修正方法能够显著提高模型判别精度,其中应用SVM算法对修正后的光谱建立模型效果最好,对训练集和测试集的判别准确率分别为99. 34%和90. 20%,相对于原始光谱建立的模型判别准确率分别提高了7. 84和5. 89个百分点。基于此方法修正果实直径对于透射光谱的影响是可行的,构建的模型能够实现苹果霉心病的准确判别。     

基于可见/近红外光谱谱区有效波长的梨品种鉴别

基于最小二乘支持向量机(LS-SVM)建模方法,提出应用梨在可见/近红外光谱谱区的有效波长(EW)进行其品种鉴别的新方法.用210个样本作为建模定标集,30个样本进行预测.根据偏最小二乘法分析载荷图和回归系数图选择鉴别梨品种的有效波长,并建立EW与最小二乘支持向量机相结合的EW-LS-SVM模型,同时与应用逆反馈人工神经网络(BP-ANN)建立的EW-BP-ANN模型进行判别准确率的比较.结果表明,应用LS-SVM和BP-ANN建立的模型对建模样本和预测集样本的判别准确率分别为100％和93.3％.研究表明,应用EW-LS-SVM模型进行梨品种鉴别是可行的.     

基于支持向量机的有机肥总养分含量NIRS分析

以我国22个省市的120份畜禽粪便为原料的有机肥产品样品为研究对象,利用近红外漫反射光谱法与支持向量机相结合建立了有机肥产品中总养分含量的快速测定模型,并与偏最小二乘法所建模型作了比较.利用偏最小二乘回归法所建立的基于原始样品和干燥粉碎样品的总养分含量近红外模型验证决定系数R_v~2、预测标准差SEP和验证相对分析误差RPD分别为0.96、7.95 g/kg、2.47和0.93、8.02 g/kg、3.58.利用支持向量机回归法所建立的干燥粉碎样品中总养分含量的近红外模型验证决定系数R_v~2、预测标准差SEP和验证相对分析误差RPD分别为0.93、7.38 g/kg和3.88.结果表明,近红外漫反射光谱法可以快速测定畜禽粪便为原料的有机肥产品中总养分含量,与偏最小二乘法相比,支持向量机所建模型具有更高的预测精度.     

基于近红外光谱的掺伪油茶籽油检测

为了探索采用近红外光谱技术检测掺伪油茶籽油的潜力,以12个产地的玉米油、花生油、菜籽油和大豆油为掺杂油,以5个产地的油茶籽油为被掺杂油,制备了455份掺伪质量分数为0、1%、3%、6%、10%、15%和20%的掺伪油茶籽油,采集了所制备样品在833～2 500 nm范围内的近红外光谱。对采集的近红外光谱进行多元散射校正处理后,应用Kennard-Stone样本划分法按2∶1的比例将样本划分为校正集和测试集。采用连续投影算法(SPA)、无信息变量消除算法和竞争性自适应重加权算法提取表征掺伪油茶籽油样本的特征波长,并建立判别掺伪油茶籽油样品的支持向量机(SVM)和随机森林(RF)模型。研究结果表明,SVM模型具有较高的灵敏度,RF模型具有良好的特异性。基于SPA提取的9个特征波长所建立的RF模型的识别准确率最高,为99.34%,对掺伪质量分数为1%的掺伪油茶籽油的识别准确率达到94.74%,对掺伪质量分数为3%及以上的掺伪油茶籽油的识别准确率达到100%。本研究为掺伪油茶籽油检测仪的研发提供了基础数据。     

基于高光谱的水稻稻曲病早期监测研究

为了快速、精准地感知水稻稻曲病的发生，实现稻曲病大面积早期监测，利用机载UHD185高光谱仪采集带有发病区域的多组水稻冠层高光谱图像数据，对图像数据进行预处理并建立数据集。对健康区域和发病区域进行分类训练，建立支持向量机(SVM)识别模型和主成分分析(PCA)加人工神经网络(ANN)的识别模型，通过验证样本来检验识别模型的准确性，达到识别发病水稻的目的。支持向量机识别模型选用两组特征波长下的假彩色图像：第1组波长组合(TZH1)为654、838、898 nm;第2组波长组合(TZH2)为630、762、806 nm,两组数据的错分误差/漏分误差总体分别达到4.24%和5.41%;其中S型核函数的SVM模型诊断性能最好，总体分类精度最高可达到95.64%,Kappa系数可达到0.94,基本达到了准确识别水稻稻曲病的目的。主成分分析加人工神经网络的识别模型选用前3个主成分，贡献率分别为93.67%、2.80%、1.24%,作为最优波长建立人工神经网络识别模型；其中非线性分类的效果优于线性分类的效果，总体分类精度达到了96.41%,Kappa系数可达到0.95。通过两个实验组数据的支持向量机...     

近红外漫反射光谱检测土壤有机质和速效N的研究

利用近红外漫反射光谱检测技术对土壤有机质和速效N含量进行了相关研究。通过自行设计的NIR光谱系统测定了150个土壤样品有机质和速效N。126个土壤样品用来建立校正集模型,其余24个用来验证模型的性能。采集完整土壤样品的近红外漫反射光谱,原始光谱经移动窗口平滑处理、SNV和一阶微分预处理后,分别采用最小二乘支持向量机(LS-SVM)和偏最小二乘法(PLS),建立土壤有机质和速效N含量的定量预测数学模型。结果表明采用一阶微分结合最小二乘支持向量机(LS-SVM)所建模型的预测效果较好,土壤有机质和速效N含量定量预测数学模型的决定系数分别为0.8255和0.8015,均方根误差分别为2.84和16.80。近红外漫反射光谱作为一种检测方法,可用于评价土壤有机质和速效N含量。     

Overland water and salt flows in a set of rice paddies

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.     

瓦房店市水果生产标准化发展研究

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。     

金谷子耐旱TG118引种试种及推广应用

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。     

对《种子法》存在问题的探讨

《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。     

Review of the Egyptian experience in implementing land drainage projects

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.     

和谐社会理论建设的几点哲学思考

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。     

A European irrigation map for spatially distributed agricultural modelling

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.     

粉质仪和拉伸仪在面粉生产中的应用

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。     

农村信息化服务的现状及建设措施

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。     

车辆ABS控制算法的研究及探讨

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。