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991.
介绍了我国开放非点对点消息网间互联互通的背景,并分阶段对我国实现非点对点消息网间互联互通的技术方案进行了介绍和分析。 相似文献
992.
《国际计算机数学杂志》2012,89(3):239-241
The results obtained for a set of integrals with singularities at the endpoints using the Harris and Evans modified ten points Gauss formula are compared with those using Stenger's formula. While the Gaussian approach gives better results for a comparable number of points, the Stenger rule is easily applied with an arbitrary number of nodes and the comparison should be more favorable when more nodes are used. 相似文献
993.
《国际计算机数学杂志》2012,89(13):2945-2952
In this article, we study the convergence of an inexact Uzawa-type algorithm for solving stabilized saddle point problems. It is shown that for stabilized problems, the algorithm converges under the same condition as that in classical case. 相似文献
994.
The purpose of this paper is to investigate the characteristics of the dissemination of information in the community. A variety of possible factors that affect the dissemination of information in Sina Weibo have been discussed. By analyzing the process of the information dissemination in the community of Sina Weibo, we found the information dissemination of Weibo community and the dynamic model are very similar. With the aid of data intensive computing theory, the various features have been mined and modeled. The dynamic model is improved and redefined to characterize the community. Then the SEINR model is proposed. The basic reproductive number, the existence of equilibrium point and the stability of the network are analyzed and proved in detail. By comparing with real data in Weibo community, we show that the SEINR model accurately reflects the dissemination of information community. Furthermore, we investigate the SEINR model in detail to show the influences of different parameters on information dissemination by simulations. 相似文献
995.
In this paper, we present a new approach for junction detection and characterization in line-drawing images. We formulate this problem as searching for optimal meeting points of median lines. In this context, the main contribution of the proposed approach is three-fold. First, a new algorithm for the determination of the support region is presented using the linear least squares technique, making it robust to digitization effects. Second, an efficient algorithm is proposed to detect and conceptually remove all distorted zones, retaining reliable line segments only. These line segments are then locally characterized to form a local structure representation of each crossing zone. Finally, a novel optimization algorithm is presented to reconstruct the junctions. Junction characterization is then simply derived. The proposed approach is very highly robust to common geometry transformations and can resist a satisfactory level of noise/degradation. Furthermore, it works very efficiently in terms of time complexity and requires no prior knowledge of the document content. Extensive evaluations have been performed to validate the proposed approach using other baseline methods. An application of symbol spotting is also provided, demonstrating quite good results. 相似文献
996.
Most GPS positioning errors can be eliminated or removed by the differential technique or the modeling method, but the multipath effect is a special kind of system or gross error, so it is difficult to be simulated or eliminated. In order to improve the accuracy of GPS positioning, the single-epoch pseudorange multipath effects at GPS station were calculated, and firstly modeled based on the spherical cap harmonic (SCH), which is the function of satellite longitude and latitude with the robust method. The accuracy of the kinematic point positioning technique was improved by correcting pseudorange observations with the multipath effect calculated by the SCH model, especially in the elevation direction. The spherical cap harmonic can be used to model the pseudorange multipath effect. 相似文献
997.
空气预热器是加热炉的重要设备,在炼油厂主要起到节能减排的作用,随着国家能源政策和环保政策的日益加强,其重要性愈发突出。通过对现有炼油加热炉空气预热器的种类、性能进行分类、对比,指出其优缺点及发展方向,并结合实际对将来的空气预热器进行展望。 相似文献
998.
结合国际学校工程实际情况,详细介绍了现浇钢筋混凝土空心楼盖采用高分子组合芯模的施工工艺及相关技术要点,同时对其关键部位控制要点及检查验收作了简要说明,并针对施工中发现的问题提出了相应的处理措施,以指导今后同类工程。 相似文献
999.
1000.
为了解决尺度不变特征变换(SIFT)算法在图像匹配中匹配正确率低、耗时长等问题,提出一种基于改进网格运动统计特征RANSAC-GMS的图像匹配算法。首先,利用快速旋转不变性特征(ORB)算法对图像进行预匹配,对预匹配的特征点采用网格运动统计(GMS)来支持估计量以实现正确匹配点与错误匹配点的区分;然后,采用改进的随机抽样一致性(RANSAC)算法通过匹配点间的距离相似性对特征点进行筛选,并采用评价函数对筛选后的新数据集进行重新整理,进而实现对误匹配点的剔除。采用Oxford标准图库和现实中拍摄的图像对图像匹配算法进行测试对比,实验结果表明,所提算法在图像匹配中的平均匹配正确率达到91%以上;与GMS、SIFT、ORB等算法相比,该改进算法的近景匹配正确率和远景匹配正确率分别最少提高了16.15个百分点和3.56个百分点,说明它能有效剔除误匹配点,进一步提高图像匹配精度。 相似文献