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91.
Y. Li G. C. L. Wong E. Caine E. L. Hu C. R. Safinya 《International Journal of Thermophysics》1998,19(4):1165-1174
We have used lithographically patterned microchannel arrays with channel widths ranging from 1 to 20 m, fabricated using electron beam lithography and reactive ion etching, in structural studies of DNA–cationic lipid complexes in confinement. Various techniques have been developed for loading these DNA–membrane complexes into the microchannels or to form the complexes in situ by sequentially depositing DNA and lipid solutions into the microchannels. Optical microscopy studies indicate that such complex formation is strongly influenced by the periodic channel structure even at channel widths much larger than the persistent length of the DNA molecules. Preliminary x-ray diffraction experiments conducted at Stanford Synchrotron Radiation Laboratory (SSRL) yielded only a weak signal from the lipid bilayers in the complexes. The use of a microfocused x-ray beam produced by the newly developed Bragg–Fresnel optics at a third-generation synchrotron facility may dramatically increase the signal-to-noise ratio and allow observation of orientational as well as positional ordering of DNA molecules induced by the microchannels. Structural control of the DNA–membrane complexes has a broad range of potential applications in gene probe technology and as mesoscopic biomolecular composites. 相似文献
92.
In this paper, the dynamic behaviors of a class of neural networks with time-varying delays are investigated. Some less weak
sufficient conditions based on p-norm and ∞-norm are obtained to guarantee the existence, uniqueness of the equilibrium point for the addressed neural networks
without impulsive control by applying homeomorphism theory. And then, by utilizing inequality technique, Lyapunov functional
method and the analysis method, some new and useful criteria of the globally exponential stability with respect to the equilibrium
point under impulsive control we assumed are derived based on p-norm and ∞-norm, respectively. Finally, an example with simulation is given to show the effectiveness of the obtained results. 相似文献
93.
提出一种以词性为参考值的文本挖掘算法,能有效挖掘与种子词有关的关联规则。基于Bootstrapping算法思想,既减少了预处理阶段对于词根还原的依赖,能处理日志中出现的中文词汇。增加了对于日志文本上下的理解,提高了关联规则的有效性,并应用与IDS日志挖掘之中,有效改善挖掘效率,为规则库提供关联规则。 相似文献
94.
The main theme of this paper is to present a novel evolution, the genetic regulatory network-based symbiotic evolution (GRNSE), to improve the convergent speed and solution accuracy of genetic algorithms. The proposed GRNSE utilizes genetic regulatory network (GRN) reinforcement learning to improve the diversity and symbiotic evolution (SE) initialization to achieve the parallelism. In particular, GRN-based learning increases the global rate by regulating members of genes in symbiotic evolution. To compare the efficiency of the proposed method, we adopt 41 benchmarks that contain many nonlinear and complex optimal problems. The influences of dimension, individual population size, and gene population size are examined. A new control parameter, the population rate is introduced to initiate the ratio between the gene and chromosome. Finally, all the studies of there 41 benchmarks demonstrate that from the statistic point of view, GRNSE give a better convergence speed and a more accurate optimal solution than GA and SE. 相似文献
95.
This paper addresses the food distribution decision from a wholesaler's perspective, as the wholesalers are often faced with thorny issues such as when, where, how to deliver products at the lowest costs to best satisfy the retailers’ changing needs. This research relies on a distribution problem encountered at Northern Grocery Company in Beijing as an example to develop a two-stage solution procedure and subsequent computer-enabled programs for identifying efficient vehicle routing alternatives. The solution process, which integrates heuristic search algorithms and an integer programming model, can be applied to a wide range of distribution problems with specified route durations and a circular transportation network structure as exemplified by City of Beijing. 相似文献
96.
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98.
Hu Changhui Lu Xiaobo Ye Mengjun Zeng Weili Du Yijun 《Multimedia Tools and Applications》2017,76(24):26523-26550
Multimedia Tools and Applications - The extended sparse representation classifier (ESRC) is one of the state-of-the-art solutions for single sample face recognition, but it performs... 相似文献
99.
Jialiang Sun Qiang Tian Haiyan Hu 《Structural and Multidisciplinary Optimization》2017,55(4):1159-1177
A topology optimization methodology is proposed for the flexible multibody system undergoing both large overall motion and large deformation. The system of concern is modeled via the absolute nodal coordinate formulation. The equivalent static load method is employed to transform the topology optimization of the nonlinear dynamic response of the system into a static one, and evaluated to adapt to the absolute nodal coordinate formulation by splitting the elastic deformations of the flexible components from the overall motions of those components. During the static topology optimization, the material interface is implicitly described as the zero level set of a higher-dimensional scalar function. Then, the semi-implicit level set method with the additive operator splitting algorithm is employed to solve the corresponding Hamilton-Jacobi partial differential equation. In addition, the expert evaluation method of weights based on the grey theory is utilized to define the objective function, and a modified augmented Lagrange multiplier method is proposed to treat the inequality volume constraint so as to avoid the oscillation and drift of the volume. Finally, two numerical examples are provided to validate the proposed methodology. 相似文献
100.
用于半自动视频对象提取的自适应网格图像分割 总被引:3,自引:0,他引:3
随着MPEG-4标准的发展和基于内容的视频处理研究,视频对象平面(VOP)的有效产生成为一个关键问题。本文提出一种基于区域的自适应网格彩色图像分割方法,可用于获得半自动视频对象跟踪和提取所需的初始VOP。该方法利用CIE L*a*b*色彩空间的特征量,对视频序列的第一帧进行三角形网格的分裂与合并。对MPEG-4标准测试序列的分割实验取得了较好的结果。 相似文献