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241.
Type-2 Fuzzy Markov Random Fields and Their Application to Handwritten Chinese Character Recognition 总被引:1,自引:0,他引:1
Jia Zeng Zhi-Qiang Liu 《Fuzzy Systems, IEEE Transactions on》2008,16(3):747-760
In this paper, we integrate type-2 (T2) fuzzy sets with Markov random fields (MRFs) referred to as T2 FMRFs, which may handle both fuzziness and randomness in the structural pattern representation. On the one hand, the T2 membership function (MF) has a 3-D structure in which the primary MF describes randomness and the secondary MF evaluates the fuzziness of the primary MF. On the other hand, MRFs can represent patterns statistical-structurally in terms of neighborhood system and clique potentials and, thus, have been widely applied to image analysis and computer vision. In the proposed T2 FMRFs, we define the same neighborhood system as that in classical MRFs. To describe uncertain structural information in patterns, we derive the fuzzy likelihood clique potentials from T2 fuzzy Gaussian mixture models. The fuzzy prior clique potentials are penalties for the mismatched structures based on prior knowledge. Because Chinese characters have hierarchical structures, we use T2 FMRFs to model character structures in the handwritten Chinese character recognition system. The overall recognition rate is 99.07%, which confirms the effectiveness of the proposed method. 相似文献
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243.
Wang Z Zeng F Li H Ye Z Bai Y Xia W Liang B 《Computer methods and programs in biomedicine》2007,86(1):39-44
Evaluation of renal vasculature was necessary for preoperative donor assessment in living donor kidney transplantation, and the ability to view the vascular imaging in three-dimensional (3D) space should be helpful undoubtedly. Considering the widespread use of personal computer (PC) systems, we aimed to find a handy way to display the anatomy of the renal arterial and venous systems of potential donors on PC-Windows platform. Ten living-related donors were included in this study. Serial computed tomography (CT) images were loaded into Amira 3.1 running on a PC with Windows XP. Following image crop, segmentation and 3D reconstruction, we got the 3D images and the video clips. According to the displays which were confirmed by latter intraoperative findings, eight donors had single renal vessels, one had a left accessory renal artery and one had a right accessory renal artery. This project offered a new approach to evaluate the renal vessel anatomy in living donor kidney transplantation, and it was favorable for accuracy and popularizing. 相似文献
244.
主动网络的通信、安全及管理机制 总被引:3,自引:0,他引:3
传统的被动网络只简单地转发信包,而不作任何计算处理工作,用户对网络业务的开发和应用受到严重限制,主动网络为这些问题提供了较好的解决方法,在网络的体系结构上起到了质的飞跃,但是与此同时,也给网络的安全和管理等方面增加了困难,本文首先介绍了主动网络的产生和体系结构;然后详细论述了主动网络的通信、安全及管理机制;最后讨论了主动网络的发展趋势和研究重点。 相似文献
245.
本文运用ODP的分析方法对基于SNMP和CMIP以及分布式的网络管理系统模型进行分析,从信息和计算视点进行对比,找出各自的特点和不足,得出网络管理系统发展的一般趋势以及需要解决的问题,为以后网络管理系统的实施提供参考。 相似文献
246.
1.引 言 航天技术的发展带来了超大量的数据,如何从这些超大量的数据中获取所需的信息已成为航天技术发展迫切需要解决的关键技术之一.战略导弹的研制与定型和载人航天工程需要高精度的外测、遥测、光测测量数据.从多套、多站、多种测量设备的联合测量数据中摸清误差规律、调整参数到优选模型环节需要处理成百上千个线性和非线性模型,需要建立一个十分复杂和庞大的数据处理集成系统,其计算量是十分巨大的. 从已知的(多参数的)大型线性模型与非线性模型中,以提高数据处理的质量为依据,建立优选模型的准则,并提供有效的计算方法… 相似文献
247.
248.
In this letter, some sufficient conditions are obtained to guarantee recurrent neural networks with linear saturation activation functions, and time-varying delays have multiequilibria located in the saturation region and the boundaries of the saturation region. These results on pattern characterization are used to analyze and design autoassociative memories, which are directly based on the parameters of the neural networks. Moreover, a formula for the numbers of spurious equilibria is also derived. Four design procedures for recurrent neural networks with linear saturation activation functions and time-varying delays are developed based on stability results. Two of these procedures allow the neural network to be capable of learning and forgetting. Finally, simulation results demonstrate the validity and characteristics of the proposed approach. 相似文献
249.
250.
Surface tensions of the Sn–Ga–In ternary alloy are calculated from the surface tensions of the Sn–Ga, Ga–In and In–Sn sub-binary systems by using geometric models (the Kohler model and the Toop model), and a general solution model (the Chou model). The calculated results are in excellent agreement with the experimental data (except for the Kohler model), assuming an experimental accuracy of ±2.5%. At the same time, the surface tensions of the Sn–Ga–In ternary alloy at 773 K and their sub-binary systems are predicted on the basis of Butler’s equation, in combination with thermodynamic data, and different model parameters β equal to the ratio of the coordination number in the surface phase to that in the bulk phase. Different values of β have almost no influence on the surface tensions. The predicted results agree with the experimental data. Therefore, the resulting iso-surface tension curves for the Sn–Ga–In ternary alloy at 773 K, especially those calculated by using the Toop model, are reasonable. 相似文献