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1.
Carotenoids are an essential component of cashew and can be used in pharmaceuticals, cosmetics, natural pigment, food additives, among other applications. The present work focuses on optimizing and comparing conventional and ultrasound-assisted extraction methods. Every optimization step took place with a 1:1 (w:w) mixture of yellow and red cashew apples lyophilized and ground in a cryogenic mill. A Simplex-centroid design was applied for both methods, and the solvents acetone, methanol, ethanol, and petroleum ether were evaluated. After choosing the extractor solvent, a central composite design was applied to optimize the sample mass (59–201 mg) and extraction time (6–34 min). The optimum conditions for the extractor solvent were 38% acetone, 30% ethanol, and 32% petroleum ether for CE and a mixture of 44% acetone and 56% methanol for UAE. The best experimental conditions for UAE were a sonication time of 19 min and a sample mass of 153 mg, while the CE was 23 min and 136 mg. Comparing red and yellow cashews, red cashews showed a higher carotenoid content in both methodologies. The UAE methodology was ca. 21% faster, presented a more straightforward composition of extracting solution, showed an average yield of superior carotenoid content in all samples compared to CE. Therefore, UAE has demonstrated a simple, efficient, fast, low-cost adjustment methodology and a reliable alternative for other applications involving these bioactive compounds in the studied or similar matrix.  相似文献   
2.
The aim of this paper is to present a new classification and regression algorithm based on Artificial Intelligence. The main feature of this algorithm, which will be called Code2Vect, is the nature of the data to treat: qualitative or quantitative and continuous or discrete. Contrary to other artificial intelligence techniques based on the “Big-Data,” this new approach will enable working with a reduced amount of data, within the so-called “Smart Data” paradigm. Moreover, the main purpose of this algorithm is to enable the representation of high-dimensional data and more specifically grouping and visualizing this data according to a given target. For that purpose, the data will be projected into a vectorial space equipped with an appropriate metric, able to group data according to their affinity (with respect to a given output of interest). Furthermore, another application of this algorithm lies on its prediction capability. As it occurs with most common data-mining techniques such as regression trees, by giving an input the output will be inferred, in this case considering the nature of the data formerly described. In order to illustrate its potentialities, two different applications will be addressed, one concerning the representation of high-dimensional and categorical data and another featuring the prediction capabilities of the algorithm.  相似文献   
3.
Visible and near-infrared(VNIR)spectroscopy is an eco-friendly method used for estimating plant nutrient deficiencies.The aim of this study was to investigate the possibility of using VNIR method for estimating Zn content in cherry orchard leaves under field conditions.The study was conducted in 3different locations in Isparta region of Turkey.Fifteen cherry orchards containing normal and Zn deficient plants were chosen,and 60 leaf samples were collected from each location.The reflectance spectra of the leaves were measured with an ASD FieldSpec HandHeld spectroradiometer and a plant probe.The Zn contents of leaf samples were predicted through laboratory analysis.The spectral reflectance measurements were used to estimate the Zn levels using stepwise multiple linear regression analysis method.Prediction models were created using the highest coefficient of determination value.The results show that Zn content of cherry trees can be estimated using the VNIR spectroscopic method(87.5相似文献   
4.
Abstract

The binding of a series of PAT analogues (rodenticides) to the [3H]-mepyramine-labelled H1 receptor in rat and guinea pig brain was investigated topologically using negentropy (N), molecular redundancy (MRI), first-order molecular connectivity (1X v ), Wiener (W), and Szeged (Sz) indices. Multiple regression analyses showed that MRI provided excellent results upon introduction of indicator parameters. Predictive ability of the proposed models was discussed using cross-validation parameters.  相似文献   
5.
转炉终点碳含量在线检测对实现炼钢终点准确控制,提高钢铁产品质量,降低能耗,减少废气排放具有重要意义。针对转炉冶炼终点控制及碳含量检测的难题,研究了一种新的基于炉口辐射光谱分析的非接触式在线碳含量检测方法。方法基于辐射光谱的支持向量机回归(SVR)实现转炉终点前过程的碳含量预测。通过远距离光谱采集系统获取炉口火焰光谱信息,基于冶炼过程炉口火焰辐射光谱变化规律的分析,分别提取了表征辐射光谱整体特征的两个参数即总谱宽和辐射峰值、以及表征发射谱的三个特征波长600,630和775 nm处的幅值作为支持向量机的输入,结合脱碳理论和实测碳值拟合重构的脱碳函数曲线作为支持向量机的输出,利用支持向量机回归方法建立光谱分布与碳含量的关系模型。通过训练样本集和测试集循环优化确定模型最佳参数。设计的仪器和优选的模型已安装在转炉生产现场长时间运行,现场实验结果表明,终点碳含量检测准确率为90.2%,测量时间小于0.3 s,可实时在线检测,能够满足生产需求,为转炉冶炼终点的精确控制提供了重要依据。  相似文献   
6.
太赫兹光谱技术用于干旱胁迫下大豆冠层含水量检测研究   总被引:1,自引:0,他引:1  
近年来水资源短缺问题日益严重,部分地区由于农业灌溉用水不足导致庄稼减产农民利益受损。大豆是一种需水量较大的农作物,一旦水分亏缺将直接影响大豆植株的形态和生长发育,从而造成大豆品质降低和产量减少。大豆叶片的水分状况可真实地反映植株水分受土壤水分亏缺的影响程度,因此,大豆冠层叶片水分含量的快速获取成为一种需要。太赫兹辐射在水中的强烈衰减使其成为一种非常灵敏的非接触式探针,可以快速、无损地检测叶片含水量。因此基于太赫兹光谱这一新技术进行大豆冠层叶片含水量的检测研究,用于实时监测田间大豆的健康状况。实验选用中黄13号大豆进行栽培,为尽可能模拟田间不同程度的干旱胁迫状况,将开花期大豆进行5个不同梯度:正常供水、轻度干旱胁迫、中度干旱胁迫、重度干旱胁迫、严重干旱胁迫(分别占田间最大持水量的80%,65%,50%,35%,20%)的水分灌溉,每个梯度设置3个重复。利用人工称重法与便携式土壤水分速测仪结合将土壤含水量调控到各水分梯度要求。然后,将实验大豆植株运回实验室并利用透射式太赫兹时域光谱仪进行样本扫描,每个梯度采集18片冠层叶片,共90个样本,以2∶1的比例分为校正集和预测集。在获取各样本时域光谱数据后,根据Dorney和Duvillaret提出的模型进行了光学参数的提取,得到各样本的吸收系数谱以及折射率谱。定性分析了太赫兹时域光谱、吸收系数、折射率随水分胁迫程度不同的变化情况。实验发现:随着水分胁迫程度的降低,时域光谱的峰值呈不断衰减趋势,且均低于空白参考峰值,同时有明显的时间延迟。吸收系数值随干旱胁迫程度的加剧逐渐降低;折射率值同样随干旱胁迫程度的加剧逐渐降低。并利用偏最小二乘(PLS)和多元线性回归(MLR)方法定量研究了时域光谱、吸收系数、折射率光谱数据与叶片含水率的相关关系。结果表明,太赫兹波对大豆叶片水分差异十分敏感,基于时域光谱最大值和最小值的MLR预测精度最高,预测集相关性(rp)达-0.939 3,均方根误差(RMSEP)为0.049 5。研究表明太赫兹光谱技术应用于大豆冠层叶片含水量观测具有良好的可行性,为开展大豆冠层含水量信息快速获取,实现科学节水管理与灌溉决策提供了新的检测手段和实验依据。  相似文献   
7.
There is a growing attention to the bio and renewable energies due to fast depletion of fossil fuels as well as the global warming problem. Here, we developed a modeling and simulation method by means of artificial intelligence (AI) for prediction of the bioenergy production from vegetable bean oil. AI methods are well known for prediction of complex and nonlinear process. Three distinct Adaptive Boosted models including Huber regression, LASSO, and Support Vector Regression (SVR) as well as artificial neural network (ANN) were applied in this study to predict actual yield of Fatty acid methyl esters (FAME) production. All boosted utilizing the Adaptive boosting algorithm. The important influencing parameters on the biodiesel production such as the catalyst loading (CAO/Ag, wt%) and methanol to oil (Soybean oil) molar ratio were selected as the input variables of models while the yield of FAME production was selected as output. Model hyper-parameters were tuned to maintain generality while improving prediction accuracy. The models were evaluated using three distinct metrics Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and R2. Error rates of 8.16780E-01, 4.43895E-01, 2.06692E + 00, and 3.92713 E-01 were obtained with the MAE metric for boosted Huber, SVR, LASSO and ANN models. On the other hand, the RMSE error of these models were about 1.092E-02, 1.015E-02, 2.669E-02, and 1.01174E-02, respectively. Finally, the R-square score were calculated for boosted Huber, boosted SVR, and boosted LASSO as 0.976, 0.990, 0.872, and 0.99702, respectively. Therefore, it can be concluded that although the boosted SVR and ANN models were better models for prediction of process efficiency in terms of error, but all algorithms had high accuracy. The optimum yield of 83.77% and 81.60% for biodiesel production were observed at optimum operating values from boosted SVR and ANN models, respectively.  相似文献   
8.
在工业现场生产水泥的过程中,各种成分的含量直接影响着水泥的质量,因此如何快速准确地监测水泥中各个成分的含量意义重大。采用的实验方式为,将不经过任何预处理的水泥粉末直接放入位于二维移动平台上的物料盒中,通过激光诱导击穿光谱(LIBS)直接对水泥粉末表面的不同位置进行激发检测,对得到的光谱数据首先进行归一化和主成分分析等预处理操作,然后针对水泥中Ca, Si, Al, Fe, Mg五种元素,分别建立偏最小二乘(PLS)和支持向量回归(SVR)两种定量分析模型进行方法比较。此外,对比了粉末状水泥与压片式水泥两种测量方式的结果。实验结果表明,采用粉末状水泥直接测量的方式下,针对水泥样品元素浓度与所得到的光谱中特征线强度的关系,SVR方法比PLS方法更具优势,粉末状水泥直接测量的精度接近压片式测量的精度,说明LIBS技术对水泥粉末状样品直接在线测量具有可行性。  相似文献   
9.
Surface roughness is one of the most common performance measurements in machining process and an effective parameter in representing the quality of machined surface. The minimization of the machining performance measurement such as surface roughness (Ra) must be formulated in the standard mathematical model. To predict the minimum Ra value, the process of modeling is taken in this study. The developed model deals with real experimental data of the Ra in the end milling machining process. Two modeling approaches, regression and Artificial Neural Network (ANN), are applied to predict the minimum Ra value. The results show that regression and ANN models have reduced the minimum Ra value of real experimental data by about 1.57% and 1.05%, respectively.  相似文献   
10.
建立基于光谱分析的轮台白杏叶片铁(Fe)、锰(Mn)元素浓度估算模型,为快速建立轮台白杏树体微量营养元素诊断体系提供技术途经。采用Unispec-SC光谱仪测定土壤肥力存在显著差异条件下轮台白杏果实不同生育时期叶片的光谱反射率,通过分析叶片中Fe和Mn元素浓度与Rλ和f′(Rλ)的相关性,筛选出光谱指示波段,并采用线性回归模型建立光谱估算模型以估算叶片Fe和Mn营养元素浓度。结果表明:轮台白杏果实不同生育时期叶片Fe元素的光谱敏感波段各不相同,果实坐果期和硬核期敏感波段分别为873和874nm,375和437nm。果实成熟期敏感波段为836和837nm而果实收后期敏感波段为325和1 054nm;轮台白杏果实四个生育时期Mn元素的光谱敏感波段分别为913和1 129nm,425和970nm,390和466nm,423和424nm;轮台白杏叶片Fe和Mn元素浓度均与光谱反射率一阶微分f′(Rλ)相关性最强,与之建立的线性光谱估算模型拟合度最高,且达到了显著或极显著水平。表明果实不同生育时期,轮台白杏叶片Fe和Mn元素的光谱指示波段不同,可根据双波段f′(Rλ)采用线性模型估算白杏叶片Fe和Mn元素浓度。  相似文献   
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