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51.
By means of the torus knot theory method, this paper presents the complete process of obtaining the knotted pictures of eight GHZ states on the surface of a trivial torus from the knotted pictures of eight basic three-qubit states on the surface of a trivial torus. Thus, we obtain eight knotted pictures 121 linkage on the ordinary plane. 相似文献
52.
Scaling predictions for bottle‐brush polymers with a rigid backbone and flexible side chains under good solvent conditions are discussed and their validity is assessed by a comparison with Monte Carlo simulations of a simple lattice model. It is shown that typically only a rather weak stretching of the side chains is realized, and then the scaling predictions are not applicable. Also two‐component bottle brush polymers are considered, where two types (A,B) of side chains are grafted, assuming that monomers of different kind repel each other. In this case, variable solvent quality is allowed. Theories predict “Janus cylinder”‐type phase separation along the backbone in this case. The Monte Carlo simulations, using the pruned‐enriched Rosenbluth method (PERM) give evidence that the phase separation between an A‐rich part of the cylindrical molecule and a B‐rich part can only occur locally. The correlation length of this microphase separation can be controlled by the solvent quality. This lack of a phase transition is interpreted by an analogy with models for ferromagnets in one space dimension.
53.
FAN Hong-Yi FAN Yue 《理论物理通讯》2005,44(2):252-254
We extend the method of searching “eigen-operator” of the square of the Schroedinger operator to the interaction picture, which not only helps to construct Hamiltonians of two kinds of parametric amplifiers but also leads to a new uncertainty relation regarding to the free Hamiltonian and the interacting Hamiltonian. 相似文献
54.
在传统的基于运动补偿的时间滤波小波视频编码方案中,帧组尺寸和低通帧位置都是固定的,没有考虑到视频序列中运动的性质.本文提出了一种类似haar小波的基于运动补偿的时间滤波编码方案,利用互信息技术,根据视频的运动特征自适应的选择帧组尺寸和低通帧位置.同时,根据选定的帧组尺寸和低通帧位置决定时间上的编码层次.大量的实验比较了提出的方法和传统方法的压缩性能.当视频序列运动较为剧烈时,本文提出的自适应选择低通帧方法较固定低通帧方法的PSNR提高约0.3~0.5dB;当视频序列中运动缓急不一,如频繁的画面切换,本文提出的自适应的选择帧组尺寸的方法能取得更好的效果. 相似文献
55.
In this study, a novel concept of picture fuzzy threshold graph (PFTG) is introduced. It has been shown that PFTGs are free from alternating 4-cycle and it can be constructed by repeatedly adding a dominating or an isolated node. Several properties about PFTGs are discussed and obtained the results that every picture fuzzy graph (PFG) is equivalent to a PFTG under certain conditions. Also, the underlying crisp graph (UCG) of PFTG is a split graph (SG), and conversely, a given SG can be applied to constitute a PFTG. A PFTG can be decomposed in a unique way and it generates three distinct fuzzy threshold graphs (FTGs). Furthermore, two important parameters i.e., picture fuzzy (PF) threshold dimension (TD) and PF partition number (PN) of PFGs are defined. Several properties on TD and PN have also been discussed. Lastly, an application of these developed results are presented in controlling medicine resources. 相似文献
56.
针对人工检测金属表面缺陷效率低、主观意识强、无法长时间工作等缺点,提出一种基于支持向量机监督检测、分类以及测量的金属表面缺陷的方法,并使用Matlab软件设计一个图形用户界面(GUI),便于检测人员使用.研究中先对工厂采集的图像进行Gabor滤波和对比度增强的前处理.然后使用方向梯度直方图(HOG)和灰度共生矩阵(GL... 相似文献
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