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图像目标形状匹配与视频过滤技术研究 总被引:1,自引:0,他引:1
吴四九 《成都信息工程学院学报》2002,17(2):97-100
通过研究图像目标形状特征的提取、匹配,运用随机过程,投影理论,提出用于识别目标形状统计特性的波动度特征,建立目标形状匹配函数,给出实际图像目标的匹配实现算法,实际系统测试表明该算法能准确、快速完成实际图像目标形状的匹配、过滤,为图像跟踪、识别及视频过滤等应用领域提供了新的可借鉴方法。 相似文献
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The remnant resulting from the merger of two neutron stars produces neutrinos in copious amounts. In this paper we present the neutrino emission results obtained via Newtonian, high-resolution simulations of the coalescence event. These simulations use three-dimensional smoothed particle hydrodynamics together with a nuclear, temperature-dependent equation of state and a multiflavour neutrino leakage scheme. We present the details of our scheme, discuss the neutrino emission results from a neutron star coalescence and compare them with the core-collapse supernova case where neutrino emission has been studied for several decades. The average neutrino energies are similar to those in the supernova case, but contrary to the latter, the luminosities are dominated by electron-type antineutrinos that are produced in the hot, neutron-rich, thick disc of the merger remnant. The cooler parts of this disc contain substantial fractions of heavy nuclei, which, however, do not influence the overall neutrino emission results significantly. Our total neutrino luminosities from the merger event are considerably lower than those found in previous investigations. This imposes constraints on the ability of neutron star mergers to produce a gamma-ray burst via neutrino annihilation. The neutrinos are emitted preferentially along the initial binary rotation axis, an event seen 'pole-on' would appear much brighter in neutrinos than a similar event seen 'edge-on'. 相似文献
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具有匹配不确定的奇异摄动系统的鲁棒控制 总被引:2,自引:0,他引:2
对于同时具有结构匹配不确定和系统不确定量的奇异摄动系统,利用Lyapunov稳定性理论进行了鲁棒性研究。给出了1个理想奇异摄动系统的稳定鲁棒控制也是不确定奇异摄动系统稳定控制的稳定条件和鲁棒界,讨论了鲁棒界及其随参数变化的变化范围。本文是王宪杰,高存臣已有结果的推广。 相似文献
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Dynamics and Variability of Terra Nova Bay Polynya 总被引:1,自引:0,他引:1
Giannetta Fusco Daniela Flocco Giorgio Budillon Giancarlo Spezie Enrico Zambianchi 《Marine Ecology》2002,23(S1):201-209
Abstract. We present a process study on the dynamics and variability of the Terra Nova Bay polynya in the western sector of the Ross Sea. The air-sea heat exchange is known to be particularly large in polynya during the winter, when differences between air and sea temperatures are large. We apply a 1-D model (Pease, 1987; Van Woert, 1999a, 1999b), which is modified in the latent heat parameterisation in order to account for time-dependent relative humidity and cloud coverage. Furthermore, the Ice Collection Depth is correlated linearly with a variable wind speed. The model is forced with two different meteorological data sets: the operational analysis of the European Center for Medium Range Weather Forecasts atmospheric data set and the meteorological parameters measured by an Automatic Weather Station located on the coast of Terra Nova Bay. The results are compared in terms of polynya extension, ice, and High Salinity Shelf Water production. According to the two different wind velocities, the results obtained from the different data sets clearly differ. Qualitatively, however, the results are in good agreement. 相似文献
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针对空间数据库的特点,提出了一种改进的基于实例的层次式模式匹配方法,并解决了实体对应关系的自动建立、要素类相似性计算、属性相似性计算等问题.最后,通过实验验证了该方法的有效性. 相似文献
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Dynamic data integration for structural modeling: model screening approach using a distance-based model parameterization 总被引:2,自引:0,他引:2
This paper proposes a novel history-matching method where reservoir structure is inverted from dynamic fluid flow response.
The proposed workflow consists of searching for models that match production history from a large set of prior structural
model realizations. This prior set represents the reservoir structural uncertainty because of interpretation uncertainty on
seismic sections. To make such a search effective, we introduce a parameter space defined with a “similarity distance” for
accommodating this large set of realizations. The inverse solutions are found using a stochastic search method. Realistic
reservoir examples are presented to prove the applicability of the proposed method. 相似文献