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101.
Degenerate Second-Order Identification Problem in Banach Spaces   总被引:1,自引:1,他引:0  
We are concerned with a degenerate second-order identification problem in a Banach space. Suitable hypotheses on the operators involved are made in order to reduce the given problem to a nondegenerate problem. Some applications to partial differential equations are indicated extending well-known results in the regular case.  相似文献   
102.
In this paper we study the identification problems for the damped Klein-Gordon equation (KG). In particular, when the diffusion parameter of KG is unknown, we prove the existence of the optimal parameter and deduce the necessary conditions on the optimal parameter by using the transposition method.  相似文献   
103.
高光谱图像包含了大量的光谱信息和图像信息,采用高光谱成像技术对牛肉品种进行识别。获取可见-近红外(400~1000 nm)光谱范围内的安格斯牛、利木赞牛、秦川牛、西门塔尔牛、荷斯坦奶牛五个品种共252个牛肉样本的高光谱图像。在ENVI软件中对高光谱图像进行阈值分割并构建掩膜图像,获取样本的感兴趣区域(ROI),并结合伪彩色图对牛肉样本的反射率指数进行可视化表达;采用Kennard-Stone(KS)法对样本集进行划分以提高模型的预测性能;对原始光谱采用卷积平滑(SG)、区域归一化(Area normalize)、基线校正(Baseline)、一阶导数(FD)、标准正态变量变换(SNV)及多元散射校正(MSC)等6种方法进行预处理;采用竞争性自适应重加权算法(CARS)提取特征波长。然后利用颜色矩对不同牛肉样本的颜色特征进行提取;对原始光谱图像进行主成分分析,结合灰度共生矩阵(GLCM)算法,提取主要纹理特征。最后结合偏最小二乘判别(PLS-DA)算法建立牛肉样本基于特征波长、颜色特征以及纹理特征的识别模型。KS法将牛肉样本划分为校正集190个,预测集62个;将未经预处理的光谱数据与经过6种不用预处理的光谱数据进行建模分析,结果发现经FD法处理后的光谱数据所建模型的识别率最高;结合CARS法对经FD法预处理后的光谱数据进行特征波长提取,共提取出22个波长;利用颜色矩和GLCM算法分别提取出每个牛肉样本的9个颜色特征、48个纹理特征。将特征波长数据与颜色、纹理特征信息进行融合建模,结果表明,基于特征光谱+纹理特征的模型识别效果最佳,其校正集与预测集识别率分别为98.42%和93.55%,均高于特征光谱数据模型识别率,说明融合纹理特征后使样本分类信息的表达更加全面;融合颜色特征后模型的校正集识别率均有所增加,但预测集识别率稍逊,颜色特征虽携带了部分有效信息,但这些信息与牛肉样本的相关性不大。因此,寻找与牛肉样本相关性更大的颜色特征是提高模型识别率的重要途径之一。该研究结果为牛肉品种的快速无损识别提供了一定的参考。  相似文献   
104.
This paper addresses the construction of probabilistic models for time or space dependent natural hazards. The proposed method uses Karhunen-Loève expansion in order to construct an empirical model matching the non-stationarity and the randomness of natural phenomena such as earthquakes or other complex environmental processes. The terms of the Karhunen-Loève expansion are identified directly from measured data. The approach is illustrated and its performance assessed through two academic examples. It is then applied to seismic ground motion modeling using recorded data.  相似文献   
105.
106.
《Analytical letters》2012,45(7-8):581-590
Abstract

NMR analytical procedures are described for the qualitative and quantitative determination of amygdalin. The spectrum is very specific for amygdalin, particularly the sugar region. The optical nature may be conveniently ascertained from the chemical shifts of the aglycone methine hydrogens and the relative optical purity determined by comparing the corresponding peak areas. Satisfactory analyses of amygdalin-containing tablets have been carried out with a precision of 1.2% and accuracy of less than 1%.  相似文献   
107.
三维古地温度场方程的参数优化辨识   总被引:1,自引:1,他引:0  
为较真实地反映沉积盆地古地温的变化情况,本文建立了适用于不同岩性的沉积盆地地层的古地温度场方程及其定解条件;依据优化理论构造了地层物性参数的优化识别模型,并给出了该优化识别问题最优解存在的必要条件和最优化算法。  相似文献   
108.
A portable CE system was developed for the identification of cattle breeds. The system had a width of 44 cm, depth of 27 cm, height of 13 cm, and a weight of only ∼8 kg and included an LIF detector, with everything integrated into a small box. The specific sizes of genes were quickly separated and detected with a high sensitivity based on the difference in the DNA mobility using a diode‐pumped solid‐state LIF detector. Using this system, the 100‐bp DNA ladder was analyzed under a 1.0% PVP (Mr=300 000) sieving gel matrix in a fused silica capillary with LODs of 4.4–13.0 pg/μL (S/N=3) for 100–3000 bp DNAs, which indicates ten times improved value than other commercialized portable CE system. The migration times and the peak areas showed good reproducibilities with relative standard deviations that were less than 0.49 and 1.3% (n=5), respectively. Based on the difference in the DNA mobility of the microsatellite and SNP markers, Korean cattle and Holstein were exactly identified as the model cattle breeds within 32 and 3.5 min, respectively.  相似文献   
109.
1INTRODUCTIONTheseparationprocessoflarge-scaleliquidchromatographyisaunstabletransferprocess.Theseparationefficiencyisaffecteddirectlybytheadsorptionisotherms,themasstransferresistancewithinsolidadsorbentparticleandtheoperationparametersinthesystem.Therefore,thedeterminationoftheisothermsandisnecessaryfordesigningandoptimizingthechromatographicprocess.Thereareseveralmethodstodeterminekineticparameters.Carl(1992)carriedoutthekineticexperimentoftheadsorptioninacontinuousstirredtankadsorberl…  相似文献   
110.
Microplastics (MPs) have attracted wide attention all over the world as a remarkable pollutant. While MPs are spreading throughout several complex environmental matrices, various experiments till date have been preliminary concentrate on aquatic ecosystems. Terrestrial sources namely solid waste-origin have remains unexplored, although they contribute largely for aquatic microplastics origin. Simultaneously, terrestrial systems under human activity, like healthcare units, are likely to be polluted by various plastic ingredients. Solid waste MPs sources primarily include sanitary landfilling, food waste, wastewater treatment end-product (sludge), tire wear, textile washing and paint failure. These microplastics caused adverse impacts on ecosystem, environment, and health. Accordingly, the present study addressed solid waste MPs’ occurrence and sources, identification, quantification, characterization, fate, and degradation pathways for developing comprehensive management strategies following the principles of circular economy. In particularly, this paper critically demonstrated solid waste MPs sources, solid waste MPs sampling followed by identification and quantification by adopting combined chemical (e.g., spectroscopy viz., Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy), physical (e.g., microscopy such as transmission or scanning electronic microscopy, TEM or SEM) and thermal analyses. Additionally, the strengths and limitations of each analytical technique are discussed critically with practical aspect. Further, the MPs related national and international regulations or laws and their subsequent relevance to solid waste MPs management with future challenges are discussed very critically. Finally, the outcomes of the review paper will be valuable to different stakeholders for effective policy implementation.  相似文献   
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