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81.
82.
提出了动态邻接封闭区间连接方法以及基于球面特征的检索方法。依据模型封闭区间的位置关系以及所占比重对原模型的多个封闭区间进行连接,将原模型合并成一个封闭区间,计算模型各点的m值,即测地线距离函数值,分裂区间,聚合成骨架点,去除冗余点得到连通的骨架;以m值最小的骨架点为球心,在骨架上建立 N个球面,提取球面相交的特征用于检索。实验结果表明,本文算法能有效提取多封闭区间三维模型骨架,提高三维模型的查准率。 相似文献
83.
采用改进的主动轮廓模型算法,实现从蝴蝶兰花簇图像中提取单个花朵图像,为自动识别蝴蝶兰的生长状态奠定基础。首先利用改进的骨架算法和轮廓重生算法,生成蝴蝶兰花簇的初始轮廓;然后利用含有形状能量的主动轮廓模型进行轮廓的演化,使其更接近真实的蝴蝶兰花簇边缘,最后根据蝴蝶兰花蕊位置获得相应的蝴蝶兰花朵。实例验证和比对实验结果表明,该模型能够较好的分割和提取蝴蝶兰花簇中单个花朵,并具有较强的抗噪能力。利用该方法,可以较好的提取蝴蝶兰花簇中的单个花朵,与人工提取效果进行比对,正确率达到了91.5%。 相似文献
84.
The thermal pore pressure and consolidation of a saturated silty clay are experimentally studied. The specimen was heated progressively from the room temperature of 25 °C to 85 °C (T = 25 °C → 35 °C → 45 °C … → 85 °C), and then cooled from 85 °C to 25 °C (T = 85 °C → 75 °C → 65 °C … → 25 °C), with (case 1) or without (case 2) drainage between temperature stages at four confining pressures (50, 100, 150 and 200 kPa, respectively). It shows that during the undrained heating/cooling, the pore pressure reaches a peak at the time when the specimen is heated to the required temperature and then decreases slightly, and it declines to a minimum at the time when the specimen is cooled to the required temperature and then increases slightly. Such phenomenon can be attributed to the adjustment of soil structure induced by the interaction of solid grains with pore water. On the other hand, during the drained heating/cooling, the maximum pore pressure increases with the increase of temperature stages, and the normalized negative pore pressures show a decreasing trend with the decrease of temperature stages. This appears to be especially obvious as the applied confining pressures decrease. It is also observed that consolidation volumetric strains during the isothermal drainage increase significantly with the increase of temperature stage, and the reduction in the volumetric strains due to absorption after cooling shows a decreasing trend with the decrease of temperature stage. 相似文献
85.
Nowadays, license plate recognition for parking systems is a critical task to provide automatic control of customers and payment. This paper introduces a new method for automatic recognition of license plates of vehicles by mathematical morphology.The proposed method can provide the license plate number of the plates in different light conditions, colors,sizes, and inclination(angles). The algorithm can recognize the license plates of European Union vehicles quickly and correctly. The pattern learning of mathematical skeletons has high efficiency in the process. The performance of the algorithm is demonstrated well by the test in a parking control system. 相似文献
86.
Gasified biomass is a technology that has the potential to partially replace fossil fuels for the production of heat, electricity, transport fuels, synthetic natural gas (BioSNG) and chemicals. In the context of climate change, biomass gasification is an attractive technology. It is, however, still in the early phase of its diffusion and much of the knowledge resides in the academic sector and in small companies—the technological innovation system (TIS) is in the process of being formed. Austria is one of the leading European countries in this field and much of the development in Austria can be traced to one prominent individual, Professor Hermann Hofbauer at the Technical University of Vienna. The purpose of this paper is to analyze how and the extent to which an individual academic, Professor Hofbauer, has influenced the formation of a TIS centred on gasified biomass in Austria. We find that his impact is multidimensional and significant but that there is also a frictional and intentional resistance that obstructs the commercialisation of the new technology. These sources of resistance go beyond the ability of an individual system builder to handle. Policy makers, therefore, need to add a strong element of system building activities that interact with and supplement those pursued by Professor Hofbauer. 相似文献
87.
Data from living and extinct faunas of primitive vertebrates imply very different scenarios for the origin and evolution of the dermal and oral skeletal developmental system. A direct reading of the evolutionary relationships of living primitive vertebrates implies that the dermal scales, teeth, and jaws arose synchronously with a cohort of other characters that could be considered unique to jawed vertebrates: the dermoskeleton is primitively composed of numerous scales, each derived from an individual dental papilla; teeth are primitively patterned such that they are replaced in a classical conveyor-belt system. The paleontological record provides a unique but complementary perspective in that: 1) the organisms in which the skeletal system evolved are extinct and we have no recourse but to fossils if we aim to address this problem; 2) extinct organisms can be classified among, and in the same way as, living relatives; 3) a holistic approach to the incorporation of all data provides a more complete perspective on early vertebrate evolution. This combined approach is of no greater significance than in dealing with the origin of the skeleton and, combined with recent discoveries and new phylogenetic analyses, we have been able to test and reject existing hypotheses for the origin of the skeleton and erect a new model in their place. 相似文献
88.
基于COM的VC与Matlab混合编程 总被引:2,自引:0,他引:2
介绍了一种基于组件对象模型(Component Object Model,COM)的Matlab与VC混合编程方法。它以Matlab 6.5中的Matlab COM Builder模块为转换工具,将Matlab的M函数文件转换为COM组件后应用在VC程序中。集成后的软件不仅能够充分发挥两种语言各自的优点,还可以完全脱离Matlab的运行环境。提供的实现过程和编程实例均说明此方法简单、方便、可操作性强。 相似文献
89.
QiMing Tian Author Vitae YuPin Luo Author VitaeAuthor Vitae 《Computer aided design》2006,38(2):125-133
The spiral fashion is an important kind of embroidery fashion. In the spiral fashion embroidery, a user-designed region is embroidered with a thread along a uniform spiral path whose shape is similar to the region's contours. An approach which can automatically generate this kind of embroidery path is proposed in this paper. In this approach, the region is decomposed into several ring-shaped sub-regions at first. Then these sub-regions are organized into a binary tree and the spiral lines in these sub-regions are connected to form a single path. 相似文献
90.
基于形态学的快速拐点检测统一模型 总被引:6,自引:1,他引:6
拐点检测一直是计算机的视觉和图像处理中的关键问题,传统方法是通过计算曲率来实现拐点的检测,其要求准确定位拐点所在局部区域的位置,并易受到噪声干扰,为此提出了一种的新的基于形态骨架的快速拐眯检测方法,该方法基于物体条件骨架原理,采用改进的非对称开运算算子,并利用内外骨架分别实现对物体凸点和凹点的检测,以保证对拐点检测的完整性;对于有噪声图象,则采用多刻度形态滤波进行去噪预处理;对拐点给出了统一的检测和实现模型。实验结果表明,该统一算法检测准确度高、具有旋转不变性、计算量小、硬件实现简单,对有噪声干扰图象也能很好地进行检验。 相似文献