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21.
Generating quadrilateral meshes is a highly non-trivial task, as design decisions are frequently driven by specific application demands. Automatic techniques can optimize objective quality metrics, such as mesh regularity, orthogonality, alignment and adaptivity; however, they cannot make subjective design decisions. There are a few quad meshing approaches that offer some mechanisms to include the user in the mesh generation process; however, these techniques either require a large amount of user interaction or do not provide necessary or easy to use inputs. Here, we propose a template-based approach for generating quad-only meshes from triangle surfaces. Our approach offers a flexible mechanism to allow external input, through the definition of alignment features that are respected during the mesh generation process. While allowing user inputs to support subjective design decisions, our approach also takes into account objective quality metrics to produce semi-regular, quad-only meshes that align well to desired surface features.  相似文献   
22.
This paper reviews the TPS-RPM algorithm (Chui and Rangarajan, 2003) for robustly registering two sets of points and demonstrates from a theoretical point of view its inherent limited performance when outliers are present in both point sets simultaneously. A double-sided outlier handling approach is proposed to overcome this limitation with a rigorous mathematical proof as the underlying theoretical support. This double-sided outlier handling approach is proved to be equivalent to the original formulation of the point matching problem. For a practical application, we also extend the TPS-RPM algorithms to non-rigid image registration by registering two sets of sparse features extracted from images. The intensity information of the extracted features are incorporated into feature matching in order to reduce the impact from outliers. Our experiments demonstrate the double-sided outlier handling approach and the efficiency of intensity information in assisting outlier detection.  相似文献   
23.
Evolving Teams of Predictors with Linear Genetic Programming   总被引:1,自引:0,他引:1  
This paper applies the evolution of GP teams to different classification and regression problems and compares different methods for combining the outputs of the team programs. These include hybrid approaches where (1) a neural network is used to optimize the weights of programs in a team for a common decision and (2) a realnumbered vector (the representation of evolution strategies) of weights is evolved with each term in parallel. The cooperative team approach results in an improved training and generalization performance compared to the standard GP method. The higher computational overhead of team evolution is counteracted by using a fast variant of linear GP.  相似文献   
24.
An online face recognition system is presented in the paper. To online face recognition system, we should consider the recognition rate, the image compression and image size. In the paper we researched the innovation technologies for face recognition system, including Kernel Principal Component Analysis (Kernel PCA), Delta low-pass wavelet filter, and face recognition algorithm using multiple images. Kernel PCA is derived to classify the characteristics of training images in the database. Delta low-pass wavelet filter is used to reduce the image size. A face recognition algorithm using multiple images is presented to improve the recognition rate. Simulation experiment shows that in the case of packet loss recognition rate is improved highly.  相似文献   
25.
In music analysis it is a common requirement to search a musical score for occurrences of a particular musical motif and its variants. This tedious and time-consuming task can be carried out by computer, using one of several models to specify which variants are to be included in the search. The question arises: just how many variants must be explicitly considered? The answer has a profound effect on the computer time needed. In this paper, recurrence relations and closed form analytic expressions are derived for the run time complexity of two models of fuzzy pattern matching for use in music analysis; each model assumes the existence of an atomic exact pattern matching operation. The formulae so obtained are evaluated and tabulated as a function of their independent parameters. These results enable a priori estimates to be made of the relative run times of different music searches performed using either model. This is illustrated by applying the results to an actual musical example.Richard E. Overill, BSc, PhD, C.Math, FIMA, C.Eng, MBCS, MIEE, is Lecturer in Computer Science at King's College London. His research includes the design, analysis, and practical implementation of algorithms on supercomputers. He has also given lecture-recitals on the keyboard music of the Tudor composers Thomas Tallis (1985), John Blitheman (1991), and William Byrd (1993).  相似文献   
26.
在不同国家的企业中股权结构有很大差异.多个大股东并存下的股权制衡模式作为一种特殊的股权结构,产生了其特有的公司治理问题.文中主要从多个大股东并存的公司治理效应、对于公司决策和业绩的影响、与公司价值的关系三个方面对国外研究进行了综述,较为全面的总结了前人对于多个大股东并存下的股权制衡的公司治理问题的研究.  相似文献   
27.
为了解决多重中断的执行不确定性带来的测试困难问题,在多重中断产生并发错误的特点的基础上,提出了一种多重中断程序测试框架.该测试框架通过从外部加载一组合适的中断信号序列控制中断处理程序的执行过程,迫使中断程序经历待测序列,避免了构造复杂的运行时控制环境.实验结果表明,相对于一般的中断错误分析方法,该测试框架能够对顺序程序多重中断环境下可能产生并发错误的时序环境和具体原因进行较为准确地分析.  相似文献   
28.
Prediction of the coalescence of adjacent cracks is critical for residual strength estimation of structures under multiple site damage conditions. A methodology successfully developed for the case of crack link‐up prediction of un‐stiffened plates, is extended for the case of typical cracked stiffened aircraft panels. The proposed link‐up criterion is based on the change in the magnitudes of elastic and plastic strain energies of the stiffened panel, before and after the cracks coalesce. The strain energy magnitudes of interest are calculated using non‐linear elastic–plastic finite‐element analysis. For the application and verification of the method, experimental results from the open literature are used. Residual strength values calculated by the proposed methodology are in good agreement with the experimental results. The present criterion provides superior results when compared to the existing and commonly applied link‐up criteria.  相似文献   
29.
多元回归分析在电热式平板硫化机热板温度场中的应用   总被引:2,自引:0,他引:2  
分析电热平板硫化机热板温差大的主要影响因素,重点研究热源分布情况对温差的影响.以400×400电热平板硫化机为例,应用多元回归的二次响应曲面模型及其子模型,对热源间距(电热管间距)与热板表面最大温差之间的函数关系进行预测,检验并分析预测结果(拟合曲线)的可靠程度,从而得出较合理的数学模型,即完整二次响应曲面模型.此模型可为工程设计提供参考依据.  相似文献   
30.
提高高炉清循环冷却水系统浓缩倍数的对策研究   总被引:1,自引:0,他引:1  
通过对宝钢1号高炉清循环冷却水系统的质能平衡测试和理论分析计算,找出了清循环水系统浓缩倍数偏低的真正原因,并提出了相应的技术措施,所做工作对同类系统有重要的指导意义。  相似文献   
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