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131.
Comparison of results from the more informative version of TMA with other methods of polymer testing
B. Jurkowska B. Jurkowski Y. A. Olkhov 《Journal of Thermal Analysis and Calorimetry》2005,81(1):27-33
Summary Several characteristics of the topological regions determined by the more informative version of TMA for cured rubbers based on NR/CPE and NR/ENR blends as well as PA6/cured rubber blends correlate with static and dynamic mechanical properties. These rubbers differ substantially in the structure of their network and the related topological structure because CPE does not participate in cross-links when ENR can do it. The physical interactions caused by these additives also vary, due to the different polarity that influences the formation of physical networking junctions. In blends of PA6 and cured rubber the networking junctions are assumed as being physical nature only. From these facts and the above-mentioned results it could be preliminarily concluded that the correlation depends on the formulation and related structure of the composite, and on which of the characteristics have been compared. To understand the reasons for the existence, or lack of, correlation observed, further investigations are needed. 相似文献
132.
José A. Raposo Javier Soria 《Proceedings of the American Mathematical Society》1997,125(4):1105-1109
We characterize the approach regions so that the non-tangential maximal function is of weak-type on potential spaces, for which we use a simple argument involving Carleson measure estimates.
133.
多媒质区域中电磁波传播的时域特征波模拟 总被引:1,自引:1,他引:0
将时域特征波法用于模拟多媒质区域的电磁波传播。与时域有限差分法相比,时域特征波法在处理媒质交界面和吸收边界上具有优越性。 相似文献
134.
Larry Lee 《Stochastic Processes and their Applications》1981,12(1):107-113
Tests are presented for comparing trends in the rate of occurence of events for two Poisson series. The tests are based on a product model which is similar to the one proposed by Cox [2]. The model allows arbitrary trends in the individual series. Although the density function of the observable variables does not belong to the exponential family, the method often used for exponential families is shown to be applicable for constructing the tests. 相似文献
135.
136.
基于MSER和SVM的快速交通标志检测 总被引:2,自引:2,他引:0
为解决传统的基于机器学习的交通标志检测(TSD) 方法需要对每一个待检测子窗口进行处理而导致算法实时性不高的问 题,提出了一种基于感兴趣区域(ROI)提取和机器学习的快速TSD 算法。针对传统基于颜色阈值的ROI提取方法具 有对光照变化较敏感等缺点,设计了一种颜色增强下的最大稳定极值区域(MSER)方法 ,根据标志的颜色进行 颜色增强,对颜色增强图像提取MSER得到交通标志ROI;然后在图像的多尺度滑动遍历检测 过程中,仅对包含ROI的滑 动窗口进行方向梯度直方图(HOG)特征的提取,并通过支持向量机(SVM)进 行分类判别。实验结果表明,本文改进的TSD方法在运算速度上有较大提升,具有很好的鲁 棒性,且获得了96.42%的检测率以及较低的误检数。 相似文献
137.
In recent times, the popularity of adding value to under-utilized legumes have increased to enhance their use for human consumption. Acacia seed (AS) is an underutilized legume with over 40 edible species found in Australia. The study aimed to qualitatively characterize the chemical composition of 14 common edible AS species from 27 regions in Australia using mid-infrared (MIR) spectroscopy as a rapid tool. Raw and roasted (180 °C, 5, 7, and 9 min) AS flour were analysed using MIR spectroscopy. The wavenumbers (1045 cm−1, 1641 cm−1, and 2852–2926 cm−1) in the MIR spectra show the main components in the AS samples. Principal component analysis (PCA) of the MIR data displayed the clustering of samples according to species and roasting treatment. However, regional differences within the same AS species have less of an effect on the components, as shown in the PCA plot. Statistical analysis of absorbance at specific wavenumbers showed that roasting significantly (p < 0.05) reduced the compositions of some of the AS species. The results provided a foundation for hypothesizing the compositional similarity and/or differences among AS species before and after roasting. 相似文献
138.
Dietmar Haendel Reiner Höfling Peter Kowski 《Isotopes in environmental and health studies》2013,49(4):402-406
In 1983/1984, in the course of the 28th Soviet Antarctic Expedition, waterbody, ice cover, and surrounding glaciers of the lakes Untersee and Obersee were sampled along some depth profiles. The geochemical data of those samples, now available, show the homogeneity of both large lakes in vertical (down to the maximum depth) as well as in lateral directions. The comparison of isotope and chemical composition of lake water and adjoining glacier ice suggests strong differences in the long-term evolution between the lakes Untersee and Obersee. First data from a lakelet, embedded in the large morainic area to the west of Lake Untersee, are of special interest: the δ2H values of the lakelet water are lower than those of recent regional glacier ice by 50‰ SMOW. This fact indicates that the lakelet is fed episodically by Pleistocene dead ice, covered by the morainic material. 相似文献
139.
为了克服针对特定失真类型的局限性以及避免有监督的学习过程,通过视觉注意模型和边缘信息来构造特征池,提出了一种基于特征池的不区分失真类型以及无监督的无参考图像质量评价算法.该算法不针对特定失真类型,对各种失真类型的图像都能做出较好的评价,从这个角度来说,是一种通用型算法.此外,该算法不需要主观分值的训练,因而又是一种真正的无监督的质量评价算法.而且,在提取空域特征时,考虑了人类的视觉感知特性,认为感兴趣区域以及边缘块会显著地影响人们对图像质量的评价.实验结果表明,该算法性能与人们的主观感知具有较好的一致性. 相似文献
140.
The linear stability of convection due to compositional and thermal buoyancy in Earth's outer core has been investigated. We have obtained the values of Takens-Bogdanov bifurcation points by plotting graphs of neutral curves corresponding to stationary and oscillatory convection for different values of physical parameters. We have derived a non-linear two-dimensional Landau-Ginzburg equation with real coefficients near the onset of stationary convection at a supercritical pitchfork bifurcation and two non-linear one-dimensional coupled Landau-Ginzburg type equations with complex coefficients near the onset of oscillatory convection at a supercritical Hopf bifurcation. We have studied Nusselt number contribution from a Landau-Ginzburg equation at the onset of stationary convection. We have discussed the stability regions of standing and travelling waves. We have also discussed the occurrence of secondary instabilities such as Eckhaus, zigzag and Benjamin-Feir instabilities. We have also derived the non-linear amplitude equation near the Takens-Bogdanov bifurcation point. 相似文献