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951.
在产业技术公共服务平台的影响和带动下,随着其用户规模不断扩大和信息技术的发展,越来越要求平台服务向智能化发展,有必要对其中之一的资源共享智能型系统建设进行探讨。 相似文献
952.
马鑫 《计算机光盘软件与应用》2010,(5):114-114
通过采油厂的信息化建设与实践,形成了采油厂信息建设整合提升配套技术体系;围绕勘探开发、生产运行、经营管理等三条主线全力推进信息应用的集成整合;形成分领域、按专业整合形成专业部门信息应用的整体解决方案。为采油厂信息化建设的科学发展、快速发展奠定了理论、技术、实施等基础。 相似文献
953.
There is a wish to be able to enter text into mobile computing devices at the speed of speech. Only handwritten shorthand schemes can achieve this data recording rate. A new, overall solution to the segmentation and recognition of phonetic features in Pitman shorthand is proposed in this paper. Approaches to the recognition of consonant outlines, vowel and diphthong symbols and shortforms, which are different components of Pitman shorthand, are presented. A new rule is introduced to solve the issue of smooth junctions in the consonant outlines which was normally the bottleneck for recognition. Experiments with a set of 1127 consonant outlines, 2039 vowels and diphthongs and 841 shortforms from three shorthand writers have demonstrated that the proposed solution is quite promising. The recognition accuracies for consonant outlines, vowels and diphthongs, and shortforms achieved 75.33%, 96.86% and 91.86%, respectively. From the evaluation of 461 outlines with smooth junction, the introduction of the new rule has a great positive effect on the performance of the solution. The recognition accuracy of smooth junction improves from 37.53% to 93.41% given a writing time increase of 14.42%. 相似文献
954.
955.
In the paper, the approximate controllability of linear abstract second-order infinite-dimensional dynamical systems is considered. It is proved using the frequency-domain method, that approximate controllability of second-order system can be verified by the approximate controllability conditions for the corresponding simplified first-order system. General results are then applied for approximate controllability investigation of a vibratory dynamical system modeling flexible mechanical structure. Some special cases are also considered. Moreover, remarks and comments on the relationships between different concepts of controllability are given. The paper extends earlier results on approximate controllability of second-order abstract dynamical systems. 相似文献
956.
Barbara Yersin Jonathan Maïm Fiorenzo Morini Daniel Thalmann 《The Visual computer》2008,24(10):859-870
Real-time crowd motion planning requires fast, realistic methods for path planning as well as obstacle avoidance. In a previous
work (Morini et al. in Cyberworlds International Conference, pp. 144–151, 2007), we introduced a hybrid architecture to handle real-time motion planning of thousands of pedestrians. In this article, we
present an extended version of our architecture, introducing two new features: an improved short-term collision avoidance
algorithm, and simple efficient group behavior for crowds. Our approach allows the use of several motion planning algorithms
of different precision for regions of varied interest. Pedestrian motion continuity is ensured when switching between such
algorithms. To assess our architecture, several performance tests have been conducted, as well as a subjective test demonstrating
the impact of using groups. Our results show that the architecture can plan motion in real time for several thousands of characters.
相似文献
Daniel ThalmannEmail: |
957.
We consider the Sequential Monte Carlo (SMC) method for Bayesian inference applied to the problem of information-theoretic
distributed sensor collaboration in complex environments. The robot kinematics and sensor observation under consideration
are described by nonlinear models. The exact solution to this problem is prohibitively complex due to the nonlinear nature
of the system. The SMC method is, therefore, employed to track the probabilistic kinematics of the robot and to make the corresponding
Bayesian estimates and predictions. To meet the specific requirements inherent in distributed sensors, such as low-communication
consumption and collaborative information processing, we propose a novel SMC solution that makes use of the particle filter
technique for data fusion, and the density tree representation of the a posterior distribution for information exchange between
sensor nodes. Meanwhile, an efficient numerical method is proposed for approximating the information utility in sensor selection.
A further experiment, obtained with a real robot in an indoor environment, illustrates that under the SMC framework, the optimal
sensor selection and collaboration can be implemented naturally, and significant improvement in localization accuracy is achieved
when compared to conventional methods using all sensors. 相似文献
958.
Kui Liu Wei-zheng Yuan Jin-jun Deng Bing-he Ma Cheng-yu Jiang 《Microsystem Technologies》2008,14(1):1-6
Microelectromechanical systems plays an important role for studying gaseous or liquid fluid flows experimentally due to the
dimensions of the device on the μm-scale. For aerodynamic applications, the detection of the location of the separation point
of the boundary layer is very important, which is used for active flow control and smart skin adaptive control system. This
paper presents the design and integration methods of a flexible polymide substrate micro thermal sensor array, sensor array
driver circuit, dynamic data acquisition circuit, and criterion algorithm of the boundary layer separation point. The above
algorithms were used to analyze the NACA0012 wind tunnel test data at flow conditions of the velocity 40 m/s and AOA 16°.
The result demonstrated the above system can fulfill the dynamic and real-time of the adaptive control system. 相似文献
959.
960.
在并行计算中,网络分割的质量会极大地影响并行计算的效率,然而在网络分割时并没有一个统一的质量评价指标,因此网络分割评价指标的定义以及最佳网络分割方法的构造,成为大规模网络中并行计算的一个核心问题.根据对影响并行计算效率的各种因素的分析,给出了一个网络分割评价指数的定义,并利用并行最短路径的计算验证了该评价指数的定义的正确性;并且基于社区分析,给出了一个全新的网络分割方法,理论分析表明:该网络分割方法是最优的. 相似文献