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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
嵌入式计算应用已经广泛运行在各种平台,普遍应用于各个领域,文中主要介绍在嵌入式系统上运行OSGI架构的相关操作和运行。 相似文献
992.
In this paper, a novel structure is derived for efficient implementation of digital filters as well as minimizing the finite word length (FWL) errors. Such a structure is actually an improved version of that reported previously. The performance of this new structure and the famous normalized lattice structure are analyzed by deriving the corresponding expression for the roundoff noise gain. Design examples are presented to illustrate the behavior of the proposed structure and to compare it with some existing ones. It is shown that the proposed structure outperforms the others in terms of minimizing roundoff noise as well as implementation efficiency. 相似文献
993.
In a number of prior papers we described and explored a new pattern recognition method called Margin-Setting that accomplishes
excellent generalization using very few training samples. The result was a multi-round classifier with each round consisting
of a set of hyperspheres such that if a datum fell within a certain hypersphere, it was labeled with one particular class.
Margin-Setting achieves concurrent low Vapnik-Chervonenkis (VC) dimension and high accuracy which is a consequence of partitioning
the training set into smaller sets that make this possible. This paper extends Margin-Setting from hyperspheres to hyperellipsoids
resulting in improved performance. 相似文献
994.
AND/OR search spaces accommodate advanced algorithmic schemes for graphical models which can exploit the structure of the
model. We extend and evaluate the depth-first and best-first AND/OR search algorithms to solving 0-1 Integer Linear Programs (0-1 ILP) within this framework. We also include a class
of dynamic variable ordering heuristics while exploring an AND/OR search tree for 0-1 ILPs. We demonstrate the effectiveness
of these search algorithms on a variety of benchmarks, including real-world combinatorial auctions, random uncapacitated warehouse
location problems and MAX-SAT instances. 相似文献
995.
Knowledge of the information goal of users is critical in website design, analyzing the efficacy of such designs, and in ensuring effective user-access to
desired information. Determining the information goal is complex due to the subjective and latent nature of user information
needs. This challenge is further exacerbated in media-rich websites since the semantics of media-based information is context-based
and emergent. A critical step in determining information goals lies in the identification of content pages. These are the pages which contain the information the user seeks. We propose a method to automatically determine the content
pages by taking into account the organization of the web site, the media-based information content, as well as the influence
of a specific user browsing pattern. Given a specific browsing pattern, in our method, putative content pages are identified
as the pages corresponding to the local minima of page-content entropy values. For an (unknown) user information goal this
intuitively corresponds to modeling the progressive transition of the user from pages with generic information to those with
specific information. Experimental investigations on media rich sites demonstrate the effectiveness of the technique and underline
its potential in modeling user information needs and actions in a media-rich web. 相似文献
996.
Fuzzy grey relational analysis for software effort estimation 总被引:1,自引:1,他引:0
Accurate and credible software effort estimation is a challenge for academic research and software industry. From many software
effort estimation models in existence, Estimation by Analogy (EA) is still one of the preferred techniques by software engineering
practitioners because it mimics the human problem solving approach. Accuracy of such a model depends on the characteristics
of the dataset, which is subject to considerable uncertainty. The inherent uncertainty in software attribute measurement has
significant impact on estimation accuracy because these attributes are measured based on human judgment and are often vague
and imprecise. To overcome this challenge we propose a new formal EA model based on the integration of Fuzzy set theory with
Grey Relational Analysis (GRA). Fuzzy set theory is employed to reduce uncertainty in distance measure between two tuples
at the k
th
continuous feature ( | ( xo(k) - xi(k) | ) \left( {\left| {\left( {{x_o}(k) - {x_i}(k)} \right.} \right|} \right) .GRA is a problem solving method that is used to assess the similarity between two tuples with M features. Since some of these features are not necessary to be continuous and may have nominal and ordinal scale type, aggregating
different forms of similarity measures will increase uncertainty in the similarity degree. Thus the GRA is mainly used to
reduce uncertainty in the distance measure between two software projects for both continuous and categorical features. Both
techniques are suitable when relationship between effort and other effort drivers is complex. Experimental results showed
that using integration of GRA with FL produced credible estimates when compared with the results obtained using Case-Based
Reasoning, Multiple Linear Regression and Artificial Neural Networks methods. 相似文献
997.
In this paper, the dynamic behaviors of a class of neural networks with time-varying delays are investigated. Some less weak
sufficient conditions based on p-norm and ∞-norm are obtained to guarantee the existence, uniqueness of the equilibrium point for the addressed neural networks
without impulsive control by applying homeomorphism theory. And then, by utilizing inequality technique, Lyapunov functional
method and the analysis method, some new and useful criteria of the globally exponential stability with respect to the equilibrium
point under impulsive control we assumed are derived based on p-norm and ∞-norm, respectively. Finally, an example with simulation is given to show the effectiveness of the obtained results. 相似文献
998.
999.
1000.
During the past decade, feature extraction and knowledge acquisition based on video analysis have been extensively researched and tested on many applications such as closed-circuit television(CCTV)data analysis, large-scale public event control, and other daily security monitoring and surveillance operations with various degrees of success. However, since the actual video process is a multi-phased one and encompasses extensive theories and techniques ranging from fundamental image processing, computational geometry and graphics, and machine vision, to advanced artificial intelligence, pattern analysis, and even cognitive science, there are still many important problems to resolve before it can be widely applied. Among them, video event identification and detection are two prominent ones. Comparing with the most popular frame-to-frame processing mode of most of today's approaches and systems, this project reorganizes video data as a 3D volume structure that provides the hybrid spatial and temporal information in a unified space. This paper reports an innovative technique to transform original video frames to 3D volume structures denoted by spatial and temporal features. It then highlights the volume array structure in a so-called "pre-suspicion" mechanism for a later process. The focus of this report is the development of an effective and efficient voxel-based segmentation technique suitable to the volumetric nature of video events and ready for deployment in 3D clustering operations. The paper is concluded with a performance evaluation of the devised technique and discussion on the future work for accelerating the pre-processing of the original video data. 相似文献