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41.
Mosaic models for textures 总被引:1,自引:0,他引:1
This paper deals with a class of image models based on random geometric processes. Theoretical and empirical results on properties of patterns generated using these models are summarized. These properties can be used as aids in fitting the models to images. 相似文献
42.
Forty-four patients suffering from acute and chronic schizophrenic psychoses were used to obtain, by using Lorr's scale (IMPS) and taking the changes in disease state observed within three months as a base, suggestions or pointers as to the proper treatment of disease with fluphenazine (lyorodin) which is a neuroleptically highly potent phenothiazine derivative. Megalomania, grandiose delusions apathetic and depressive syndromes showed marked tendencies toward major improvement. An "antiautistic" effect was observed in chronic patients. The effective dose was between 6 and 12 mg a day. The drug was well tolerated. In the majority of cases it was also necessary for antiparkinsonian drugs to be administered to patients. After twelve months of treatment, slight to major improvements or even freedom from symptoms could be observed in 28 cases (or 64%). 相似文献
43.
44.
Elongated black objects in black-and-white pictures can be ``thinned' to arcs and curves, without changing their connectedness, by (repeatedly) deleting black border points whose deletion does not locally disconnect the black points in their neighborhoods. This technique generalizes to gray-scale pictures if we use a weighted definition of connectedness: two points are ``connected' if there is a path joining them on which no point is lighter than either of them. We can then ``thin' dark objects by changing each point's gray level to the minimum of its neighbors' gray levels, provided this does not disconnect any pair of points in its neighborhood. Examples illustrating the performance of this technique are given. 相似文献
45.
Following the study of migration processes in the continuous domain in Part I of this paper, we reformulate the concept of migration in the discrete domain (Zm) and define Discrete Migration Processes (DMP). We demonstrate that this model is a natural discrete representation of the continuous model and maintains the model's features in a qualitative sense. We show that under discrete migration any discrete set shrinks to a limit in finitely many iterations. The discrete representation provides an advantageous basis for digitally implementing the MP model. Using this implementation we illustrate the discrete migration of various types of sets under various types of constraints. 相似文献
46.
Azriel Rosenfeld 《Pattern recognition letters》1984,2(5):311-317
In pattern recognition we often want to measure geometric properties of regions in an image, but these regions are not always ‘crisply’ defined; it is sometimes more appropriate to regard them as fuzzy subsets of the image. Many of the basic geometric properties of and relationships among regions can be generalized to fuzzy sets; these include connectedness, adjacency and surroundedness, starshapedness and convexity, area and perimeter, extent and diameter. This paper summarizes past work on such fuzzy geometric concepts, and also includes some new results. 相似文献
47.
正随着时代的发展,人们记录声音的方式有了巨大的变化。以MP3为代表的数码音频格式成为了现阶段主流的音频存储方式,这种保存方式让我们获取声音的方法越来越简便,但是这种经过转化、压缩和格式变化的保存方式让音频产生一定的失真。因此,喜爱音乐的人们开始寻找一种新的音乐保存方式与播放载体,纯音便携HiF i播放器就此让大众熟悉。 相似文献
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49.
Reshef Tenne Ronit Popovitz-Biro Anton Twersky Yaron Rosenfeld Hacohen 《Israel journal of chemistry》2001,41(1):7-14
Nanoparticles of various layered compounds having a closed cage or nanotubular structure, designated also inorganic fullerene-like (IF) materials, have been reported in the past. In this work IF-CdCl2 nanoparticles were synthesized by two methods. In one technique, a high temperature evaporation and subsequent condensation of dried cadmium chloride powder was used. In the other method, electron beam irradiation of the source powder led to its recrystallization into closed nanoparticles with a nonhollow core. The two methods are shown to produce nanoparticles of different topologies. While mostly spherical nested structures are obtained from the high temperature process, polyhedra with hexagonal or elongated rectangular characters are obtained by the electron beam induced process. The analysis also shows that, while the source (dried) powder is orthorhombic cadmium chloride monohydrate, the crystallized IF cage consists of the anhydrous 3R polytype which is not stable as bulk material in ambient atmosphere. Consistent with previous observations, this study shows that the seamless structure of the IF materials can stabilize phases, which are otherwise unstable in ambient conditions. 相似文献
50.
W. Schfer U. Rosenfeld H. Zaschke H. Stettin H. Kresse 《Advanced Synthesis \u0026amp; Catalysis》1989,331(4):631-636
Liquid Crystalline 1,3,4-Thiadiazoles. II. 1,3,4-Thiadiazoles with Cyclohexanefragments Preparation and liquid crystalline properties of disubstituted 1,3,4-thiadiazoles (1 and 2) are described. The mesomorphic behaviour of the title compounds is compared with their benzoate analogues. The dielectric anisotropy of these compounds is negative. 相似文献