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1.
针对肉类掺假的定量检测问题,建立了基于高光谱图像技术结合波长选择方法以及偏最小二乘(PLS)法的羊肉掺假无损检测方法.试验搭建了羊肉-猪肉的高光谱图像采集系统,对选取的99个样本进行高光谱图像(390~1040nm)采集并提取感兴趣区域光谱.比较了多种预处理方法对全波长模型的影响,标准正态变量校正(SNV)为最优光谱预处理方法,校正决定系数R2CV达到0.93,预测决定系数R2P达到0.96,校正均方根误差RMSECV为8.33%,预测均方根误差RMSEP为6.18%.采用多种波长选择方法对光谱全波段520个变量进行变量选择,最终确定基于竞争性自适应重加权算法(CARS)的简化模型最优,其R2C=0.96,R2CV=0.94,R2P=0.96,RMSEC=6.55%,RMSECV=7.66%,RMSEP=6.10%.高光谱图像技术结合CARS能够对掺假羊肉进行准确的定量检测,可为羊肉掺假的在线无损检测提供理论依据.  相似文献   

2.
利用高光谱技术建立一种牛肉-猪肉掺假的快速无损检测方法.通过对样本集进行划分、光谱预处理以及特征波长的选择,建立了全波长和选择波长的掺假定量检测模型.结果表明:基于基线校正光谱预处理所得的偏最小二乘回归(PLSR)预测模型最优,其交叉验证决定系数R2CV=0.97、预测决定系数R2P=0.98,均方根误差RMSECV=5.20%、RMSEP=4.23%.此外,用回归系数法优选5个波长点作为特征波长进行建模,所得模型与全波长模型相比,具有变量少、结构简单、性能更优等优点.  相似文献   

3.
利用长波近红外光谱(900~1700 nm)联用偏最小二乘(Partial Least Squares,PLS)算法快速评估小麦水分含量。通过采集7个不同品种小麦籽粒(百农201、百农207、百农307、百旱207、AK-58、冠麦1号、周麦18)的近红外反射光谱信息,经高斯滤波平滑(Gaussian Filtering Smoothing,GFS)、多元散射校正(Multiplicative Scatter Correction,MSC)和标准正态变量变换(Standard Normal Variable Correction,SNV)三种预处理后,分别利用偏最小二乘法(Partial Least Squares,PLS)挖掘光谱信息与小麦水分之间的定量关系。结果显示,经GFS预处理的近红外光谱(100个波长)构建的全波段PLS回归模型(F-PLS)的预测相关系数(RP=0.927)、预测误差(RMSEP=1.596%)和鲁棒性(ΔE=0.064)均优于另外两种光谱。采用Regression coefficient算法筛选最优波长优化F-PLS模型,以提高预测效率。结果显示,从GFS预处理光谱筛选的29个最优波长构建的O-PLS回归模型预测精度及鲁棒性均较好(R_P=0.909,RMSEP=0.229%,ΔE=0.078)。本试验表明,利用长波近红外光谱技术来快速无接触评估小麦籽粒含水率的潜力巨大。  相似文献   

4.
通过采集百农201、百农207、百农307、百旱207、AK-58、冠麦1号、周麦18等7个不同品种完整小麦籽粒的近红外光谱(900~1700 nm)信息,经高斯滤波平滑(Gaussian Filtering Smoothing,GFS)、标准化校正(Normalization Correction)和卷积平滑(Savitzky-Golay Convolution Smoothing,SGCS)三种预处理后,利用偏最小二乘回归(Partial Least Squares Regression,PLSR)算法寻找光谱信息与小麦籽粒干物质含量之间的定量关系。结果显示,经GFS预处理的近红外光谱(100个波长)构建的全波段PLSR模型(PLSR)预测相关系数(RP)为0.952,预测误差(RMSEP)为0.158%,RMSEC与RMSEP绝对值差(ΔE)为0.082,预测效果优于其他两种预处理光谱。从GFS光谱中经PLSR-β法筛选获得17个最优波长,构建的优化模型(O-PLSR)RP为0.928,RMSEP为0.191%,ΔE为0.049,其预测效果接近于PLSR模型。试验表明,利用900~1700 nm光谱可被潜在用于快速无损预测小麦籽粒干物质含量。  相似文献   

5.
本试验研究了基于近红外(900~1700 nm)高光谱成像技术快速预测不同冷藏时长(0~6天)的鸡胸肉嫩度.通过对原始光谱信息进行S-G卷积平滑及Baseline基线校正预处理,并采用偏最小二乘回归算法(PLSR)构建光谱信息与嫩度参考值之间的定量关系.结果显示,全波段原始光谱及预处理光谱构建的PLSR校正模型和预测模型相关系数R均大于0.90,预测效果良好.经回归系数法,从原始光谱、S–G卷积平滑预处理光谱及Baseline基线校正预处理光谱中分别筛选出20、20和19个最后波长,构建优化的RC-PLSR模型,预测相关系数分别为0.91、0.89及0.93,均方根误差分别为2.33、2.45及2.03.相比之下,经S-G卷积平滑预处理构建的PLSR模型和RC-PLSR模型预测效果均最优.研究表明,近红外高光谱成技术结合PLSR可实现对鸡肉嫩度的快速无损预测.  相似文献   

6.
提出了利用可见/近红外光谱技术检测新鲜茶叶叶片中含水量的方法.首先采集350~2500nm波段范围内177个新鲜茶叶叶片的光谱反射率信息,作为X变量.将不同预处理后的光谱数据建立偏最小二乘(partial least squares,PLS)模型,再利用回归系数法(regression coefficients,RC)提取全波段光谱中的特征波长并建立基于特征波长的预测模型.结果显示,利用全谱段光谱信息建立的模型中,未经预处理建立的模型最优,建模集和预测集中决定系数(coefficient of determination,R~2)分别是0.9039和0.8856,均方根误差(root mean square error,RMSE)分别是0.0092和0.0120,剩余预测偏差(residual predictive deviation,RPD)是2.9659;基于特征波长的模型中,也是未经预处理建立的模型最优,建模集和预测集中R~2分别是0.9070和0.8199,RMSE分别是0.0107和0.0151,RPD是2.3701.结果表明,可见-近红外光谱技术结合特征波长提取进行新鲜茶叶叶片中含水率检测是可行的.  相似文献   

7.
采用近红外透射光谱和移动窗口偏最小二乘(MWPLS)方法,建立污水化学需氧量(COD)近红外光谱分析的优化模型最优模型的对应波段为820-850nm,采用波长点个数为16,PLS因子数、RMSEP、Rp分别为13,25.5mg/L,0.968,预测相关很高,其预测效果明显优于全谱模型,并且采用的波长点个数远远优于全谱波...  相似文献   

8.
为快速无损地实现岩石类型精确识别,以禄丰阿纳恐龙山南缘为研究区,采集3类典型沉积岩样本(泥岩、砂岩和泥灰岩各21块),借助ASD FieldSpec3地物光谱仪获取样本在350~2 500 nm内的高光谱数据,对预处理后的原始光谱进行一阶微分和连续统去除变换,采用马氏距离对全波段光谱进行初步筛选,并使用竞争性自适应重加权算法进一步筛选特征波长,基于全波段和特征波长变量分别建立贝叶斯判别和经过粒子群算法优化的支持向量机识别模型.结果表明,马氏距离结合竞争性自适应重加权算法用来筛选特征波长能提高模型的识别准确率,有效剔除光谱中的冗余信息,其中基于连续统去除光谱构建的组合模型被选为最优沉积岩识别模型,其预测集识别准确率为0.952 4,输入模型的特征波长变量数只占全波段的1.6%.  相似文献   

9.
BP神经网络在ATR-FTIR技术微量农药溶液 检测中的应用   总被引:1,自引:1,他引:0  
利用衰减全反射傅里叶变换红外光谱(ATR-FTIR)技术分别对毒死蜱、炔螨特的微量溶液进行了检测,采用差谱、基线校正和矢量归一化对谱图进行预处理,利用BP神经网络分别使用自适应调整学习率并附加动量因子的梯度下降反向传播算法训练函数和SCG反向传播算法训练函数建立了毒死蜱和炔螨特农药溶液的定量分析模型,并对校正集和预测集进行了定量分析.毒死蜱溶液模型的分析结果为:R=0.998 6,RMSEC=0.100 0,RMSEP=0.220 1;炔螨特溶液模型的分析结果为:R=0.997 4,RMSEC=0.391 8,RMSEP=0.624 1.结果表明,BP神经网络结合ATR-FT-IR技术检测微量农药溶液含量具有快速、精度高、泛化能力强的优点,可用于农药溶液含量的快速、准确鉴定.  相似文献   

10.
以橡胶树叶片的近红外光谱信息为分析对象,运用由粗放到细致的多分辨率特征提取思想,提出了一种融合自适应间隔随机蛙与竞争自适应重加权采样(AIRF-CARS)的算法提取橡胶树叶片的光谱特征信息,从而实现了橡胶树叶片氮含量的定量分析.实验结果表明,AIRF-CARS算法有效的压缩了光谱特征的数量,通过算法选择的特征波长为22个,使得定量分析模型的预测均方根误差(RMSEP)和决定系数(R~2)分别为0.136 4%和0.959 6.因此,本文算法可以有效地提取信息量较大的波长特征,应用于近红外光谱检测的定量分析中,并为便携式田间多波段光谱仪的研发提供理论支撑.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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