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101.
The polymerization of ?‐caprolactam between the interlamellar spaces of the [TEACOOH]–montmorillonite intercalations complex was attempted using Na–montmorillonite and 10‐carboxy‐n‐decyltriethylammonium bromide to achieve [TEACOOH]–polycaprolactam–montmorillonite, in which montmorillonite (inorganic polymer) is chemically bonded with the polycaprolactam (organic polymer). The results of X‐ray and IR analysis for the samples obtained after polymerization showed that the polymerization reaction has been successfully accomplished. For the purpose of studying the polymeric reaction product more precisely, we have isolated the polymerized product from the silicate layers and analyzed it with X‐ray diffractometer and IR spectrometer. Comparison of the results of X‐ray and IR analysis between the isolated polymer and the polymer that was synthesized by the reaction of ?‐caprolactam only with the organic cation without montmorillonite showed that both obtained polymers are the same compounds. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1904–1910, 2003  相似文献   
102.
为了更为全面地表征语音情感状态,弥补线性情感特征参数在刻画不同情感类型上的不足,将相空间重构理论引入语音情感识别中来,通过分析不同情感状态下的混沌特征,提取Kolmogorov熵和关联维作为新的情感特征参数,并结合传统语音特征使用支持向量机(SVM)进行语音情感识别。实验结果表明,通过引入混沌参数,与传统物理特征进行识别的方案相比,准确率有了一定的提高,为语音情感的识别提供了一个新的研究途径。  相似文献   
103.
提出了一种基于相关向量机的MEMS陀螺仪随机漂移预测方法。针对MEMS陀螺仪随机漂移误差的非线性、不确定性等特点,建立了相关向量机预测模型,并采用EM算法获得模型的参数。针对随机漂移的混沌特性,利用相空间重构技术,将重构后的漂移序列作为输入变量进行模型的训练和预测。训练和测试结果均表明,该方法具有很好的预测效果,优于常用的时间序列分析法和支持向量机法。利用预测结果对随机漂移进行补偿,有效地提高了陀螺的使用精度。  相似文献   
104.
环境陶艺空间有三大要素特征:其一,思维空间在环境陶艺空间中的特性;其二,环境空间在环境陶艺空间中的特性;其三.陶艺作品空间与心理空间在环境陶艺空间中的特性。通过以上分析,可以看出环境陶艺空间各要素之间相互作用、具有相互依存的空间系统化的关系。  相似文献   
105.
State space approach is an effective method to mass-exchange network (MEN) synthesis. By decomposing the network into two interactive parts, a distribution network and a process operator, the synthesis problem can be formulated into a mixed integer nonlinear programming (MINLP) model. In this article, a generalized state space model based on typical MEN is established and verified in two cases. A new asymmetrical operator and cost index are also adopted to speed up the solution process. The results demonstrate the efficiency of the proposed approach.  相似文献   
106.
Approximations for general fractional order dynamic systems are of much theoretical and practical interest. In this paper, a new approximate method for fractional order integrator is proposed. The poles of the approximate model are unrelated to the order of integrator. This feature shows benefits on extending the algorithm to the systems containing various fractional orders. Then a unified approximate method is derived for general fractional order linear or nonlinear dynamic systems via combining the proposed new method with the distributed frequency model approach. Numerical examples are given to show the wide applicability of our method and to illustrate the acceptable accuracy for approximations as well.  相似文献   
107.
《Pattern recognition》2014,47(2):833-842
Ensemble clustering is a recently evolving research direction in cluster analysis and has found several different application domains. In this work the complex ensemble clustering problem is reduced to the well-known Euclidean median problem by clustering embedding in vector spaces. The Euclidean median problem is solved by the Weiszfeld algorithm and an inverse transformation maps the Euclidean median back into the clustering domain. In the experiment study different evaluation strategies are considered. The proposed embedding strategy is compared to several state-of-art ensemble clustering algorithms and demonstrates superior performance.  相似文献   
108.
This paper presents an approach for incorporating the effect of various logic synthesis options and logic level implementations into the custom instruction (CI) selection for extensible processors. This effect translates into the availability of a piecewise continuous spectrum of delay versus area choices for each CI, which in turn influences the selection of the CI set that maximizes the speedup per area cost (SPA) metric. The effectiveness of the proposed approach is evaluated by applying it to several benchmarks and comparing the results with those of a conventional technique. We also apply the methodology to the existing serialization algorithms aimed at relaxing register file constraints in multi-cycle custom instruction design. The comparison shows considerable improvements in the speedup per area compared to the custom instruction selection algorithms under the same area-budget constraint.  相似文献   
109.
We present a novel framework for polyhedral mesh editing with face‐based projective maps that preserves planarity by definition. Such meshes are essential in the field of architectural design and rationalization. By using homogeneous coordinates to describe vertices, we can parametrize the entire shape space of planar‐preserving deformations with bilinear equations. The generality of this space allows for polyhedral geometric processing methods to be conducted with ease. We demonstrate its usefulness in planar‐quadrilateral mesh subdivision, a resulting multi‐resolution editing algorithm, and novel shape‐space exploration with prescribed transformations. Furthermore, we show that our shape space is a discretization of a continuous space of conjugate‐preserving projective transformation fields on surfaces. Our shape space directly addresses planar‐quad meshes, on which we put a focus, and we further show that our framework naturally extends to meshes with faces of more than four vertices as well.  相似文献   
110.
不同缝面形态下诱导缝开裂效果对比研究   总被引:1,自引:1,他引:0  
李海枫  杨波  张国新  徐秀鸣 《水利学报》2017,48(10):1167-1174,1184
一些采用径向扭缝的碾压混凝土拱坝工程中,出现了诱导缝周边坝体混凝土开裂而诱导缝本身未张开的现象,因此需定量分析不同空间形态缝面对诱导缝开裂的影响效果。根据碾压混凝土拱坝应力变化特点以及诱导缝开裂变化规律,本文拟定含不同缝面空间形态的有限大平板和圆筒拱坝算例,利用虚拟裂纹闭合法和Richard脆性断裂准则获取空间缝面等效应力强度因子,研究缝面应力强度因子随缝面夹角的变化规律;通过对归一化后的应力强度因子求倒数,获取不同缝面夹角条件下诱导缝等效强度的修正系数即缝面空间形态影响因子,以反映不同缝面空间形态下诱导缝开裂效果。研究表明,随着缝面夹角的不断增大,缝面越不容易张开,这就意味着缝面的等效强度在逐渐增大。因此,在实际碾压混凝土拱坝设计中,诱导缝应尽量采用竖向垂直缝布置;若要布置成径向扭缝,则缝面夹角最大不宜超过10°。  相似文献   
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