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171.
A novel approach to annotating web service based on interface concept mapping and semantic expansion
Guobing Zou Yang Xiang Yanglan Gan Yixin Chen 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(5):929-938
With the rapid development of web service technology in these years, traditional standards have been matured during the process
of service registry and discovery. However, it is difficult for service requesters to discover satisfactory web services.
The reason for this phenomenon is that the traditional service organization mode lacks semantic understanding ability for
service function interface. This paper proposes a novel approach to annotating web services. We first adopt domain ontology
as a semantic context, and give our general framework of service semantic annotation. Then, interface concept mapping algorithm
and service interface expansion algorithm are respectively presented in detail. Finally, the generation process of semantic
web service repository is presented based on preceding algorithms. Simulation experiment results demonstrate that annotated
web services by the proposed method can more satisfy requirements for service requesters than traditional ones by service
matchmaking engine. It can get better service discovery effectiveness. 相似文献
172.
介绍了地形辅助导航系统的工作原理、系统组成和技术应用,着重介绍了地形辅助导航系统中位置估计、数字地图、实测高程数据采集、存储技术、组合导航、数字相关器等几项关键技术,并通过数据统计和分析对地形辅助导航系统进行了论证。 相似文献
173.
Xiaojun Yang Hongxin Zou Fang Lu Jian-jiang Ding Zhijie Zhou Daizhi Liu 《Simulation Modelling Practice and Theory》2010,18(3):304-316
With the merits such as hiding receiving, easy-deploying and high security, passive location has attracted more and more attention and plays an important role in fields as diverse as navigation, location, and tracking, etc. However, the current filters models for passive location methods are most under the framework of the probability theory, thus they can not estimate the state in some passive location with fuzzy uncertainty accurately. Although the fuzzy extended Kalman filter (FEKF) can deal with the fuzzy uncertainty, it unavoidably introduces truncation error. In this paper, based on the FEKF and the iterated extended Kalman filter (IEKF) principle, a new fuzzy passive location model is built, and moreover, an iterated fuzzy extended Kalman filter (IFEKF) is proposed for estimating the target state. Compared to the FEKF and the IEKF, the proposed algorithm can not only reduce the truncation error, but also deal with fuzzy uncertainty. Moreover, it is proved that the IFEKF update is an application of the Gauss–Newton method. Then, a fuzzy passive location algorithm is proposed. Simulation results demonstrate that the proposed approach has better estimation precision than the traditional fuzzy extended Kalman filter. 相似文献
174.
研究和实现了一种基于SLAM技术的虚实配准方法,通过将SLAM分离为定位和构图,分别利用改进的pf做位姿估计和ukf进行位置估计,进而实现整个场景内目标的位姿计算,最终完成虚实配准。一定程度上解决了传统方法中存在的视域受限问题,并同时支持户内和户外应用,提高了增强现实系统的可用性。 相似文献
175.
利用地面公网实现战术数据链远程通信研究 总被引:1,自引:0,他引:1
利用地面公共网络使地理位置远离的多个数据链系统无缝互连,可以支持和提高相对独立的多个战术数据信息链实现超视距的互操作测试和训练。文章分析了两种地面网络通信模式:虚拟专用局域网业务模式和应用层网关模式。比较两种模式应用特点,发现虚拟专用局域网业务模式可以将多个数据链网络连接成一个虚拟局域网,传输数据方便,但是应用层网关更加适合数据链接口的要求并且可以对传输数据进行处理和报文格式修改。 相似文献
176.
为了对多源信息融合技术在海战场作战指挥方面发挥的作用进行定量描述,文章在多年信息融合测试评估研究的基础上,对海战场多源信息融合所涉及的能力指标计算、归一化及综合、测试评估系统设计、测试想定设计、适合信息融合的信息源模拟器建设等涉及的关键技术进行了描述,并给出了一个实际的评估例子。 相似文献
177.
Dexuan Zou Haikuan LiuLiqun Gao Steven Li 《Engineering Applications of Artificial Intelligence》2011,24(4):616-624
An improved differential evolution algorithm (IDE) is proposed to solve task assignment problem. The IDE is an improved version of differential evolution algorithm (DE), and it modifies two important parameters of DE algorithm: scale factor and crossover rate. Specially, scale factor is adaptively adjusted According to the objective function values of all candidate solutions, and crossover rate is dynamically adjusted with the increasement of iterations. The adaptive scale factor and dynamical crossover rate are combined to increase the diversity of candidate solutions, and to enhance the exploration capacity of solution space of the proposed algorithm. In addition, a usual penalty function method is adopted to trade-off the objective and the constraints. Experimental results demonstrate that the optimal solutions obtained by the IDE algorithm are all better than those obtained by the other two DE algorithms on solving some task assignment problems. 相似文献
178.
179.
A directed searching optimization algorithm (DSO) is proposed to solve constrained optimization problems in this paper. The proposed algorithm includes two important operations — position updating and genetic mutation. Position updating enables the non-best solution vectors to mimic the best one, which is beneficial to the convergence of the DSO; genetic mutation can increase the diversity of individuals, which is beneficial to preventing the premature convergence of the DSO. In addition, we adopt the penalty function method to balance objective and constraint violations. We can obtain satisfactory solutions for constrained optimization problems by combining the DSO and the penalty function method. Experimental results indicate that the proposed algorithm can be an efficient alternative on solving constrained optimization problems. 相似文献
180.
A structured-based neural network (NN) with backpropagation through structure (BPTS) algorithm is conducted for image classification
in organizing a large image database, which is a challenging problem under investigation. Many factors can affect the results
of image classification. One of the most important factors is the architecture of a NN, which consists of input layer, hidden
layer and output layer. In this study, only the numbers of nodes in hidden layer (hidden nodes) of a NN are considered. Other
factors are kept unchanged. Two groups of experiments including 2,940 images in each group are used for the analysis. The
assessment of the effects for the first group is carried out with features described by image intensities, and, the second
group uses features described by wavelet coefficients. Experimental results demonstrate that the effects of the numbers of
hidden nodes on the reliability of classification are significant and non-linear. When the number of hidden nodes is 17, the
classification rate on training set is up to 95%, and arrives at 90% on the testing set. The results indicate that 17 is an
appropriate choice for the number of hidden nodes for the image classification when a structured-based NN with BPTS algorithm
is applied. 相似文献