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991.
Clinical pathways have been adopted for various diseases in clinical departments for quality improvement as a result of standardization
of medical activities in treatment process. Using knowledge-based decision support on the basis of clinical pathways is a
promising strategy to improve medical quality effectively. However, the clinical pathway knowledge has not been fully integrated
into treatment process and thus cannot provide comprehensive support to the actual work practice. Therefore this paper proposes
a knowledge-based clinical pathway management method which contributes to make use of clinical knowledge to support and optimize
medical practice. We have developed a knowledge-based clinical pathway management system to demonstrate how the clinical pathway
knowledge comprehensively supports the treatment process. The experiences from the use of this system show that the treatment
quality can be effectively improved by the extracted and classified clinical pathway knowledge, seamless integration of patient-specific
clinical pathway recommendations with medical tasks and the evaluating pathway deviations for optimization. 相似文献
992.
993.
Ying-Ke Lei Yang-Ming Xu Jun-An Yang Zhi-Guo Ding Jie Gui 《Pattern Analysis & Applications》2012,15(3):249-259
A novel algorithm called orthogonal discriminant local tangent space alignment (O-DLTSA) is proposed for supervised feature extraction. Derived from local tangent space alignment (LTSA), O-DLTSA not only inherits the advantages of LTSA which uses local tangent space as a representation of the local geometry so as to preserve the local structure, but also makes full use of class information and orthogonal subspace to improve discriminant power. The experimental results of applying O-DLTSA to standard face databases demonstrate the effectiveness of the proposed method. 相似文献
994.
Cognitive Radio (CR), first proposed by Mitola, has the potential to improve spectrum utilization by allowing secondary transmission in licensed primary networks, as long as the secondary transmissions do not interfere with the operation of the primary users (PUs) in the primary network. Although it is fundamental to the viability of this burgeoning technology, security aspects of CR have so far received scant attention from researchers. Initial research on CR has largely focused on the issues of resource allocation, spectrum sensing and management while security considerations are often added as an afterthought. As a result, many proposed solutions for CR, have introduced significant security gaps, intensifying the effects of selfishness, inequity, unavailability, or even malicious behaviors. This has posed challenges to quality-of-service (QoS) provisioning in Cognitive Radio Network (CRN) in the face of various network attacks like node masquerading, packet mislabeling and deliberate packet dropping. Since existing routing protocols assume that nodes will forward packets in good faith, the presence of selfish nodes coupled with the dynamic behavior of PUs can lead to excessive packet losses, high delays or even the complete failure of routing protocols in secondary networks. In this paper, we propose a cross-layer Altruistic Differentiated Service Protocol (ADSP) for the dynamic CRNs to address the QoS provisioning issue in CRNs with selfish nodes coexistence. Simulation results demonstrate that the ADSP can achieve much better performance in terms of lower delay, higher throughput and better delivery ratio for the traffic originating from collaborative nodes compared to other cognitive routing protocols in the presence of selfish nodes. 相似文献
995.
This paper presents a virtual try-on system based on augmented reality for design personalization of facial accessory products. The system offers several novel functions that support real-time evaluation and modification of eyeglasses frame. 3D glasses model is embedded within video stream of the person who is wearing the glasses. Machine learning algorithms are developed for instantaneous tracking of facial features without use of markers. The tracking result enables continuously positioning of the glasses model on the user’s face while it is moving during the try-on process. In addition to color and texture, the user can instantly modify the glasses shape through simple semantic parameters. These functions not only facilitate evaluating products highly interactive with human users, but also engage them in the design process. This work has thus implemented the concept of human-centric design personalization. 相似文献
996.
There are a lot of heterogeneous ontologies in semantic web, and the task of ontology mapping is to find their semantic relationship. There are integrated methods that only simply combine the similarity values which are used in current multi-strategy ontology mapping. The semantic information is not included in them and a lot of manual intervention is also needed, so it leads to that some factual mapping relations are missed. Addressing this issue, the work presented in this paper puts forward an ontology matching approach, which uses multi-strategy mapping technique to carry on similarity iterative computation and explores both linguistic and structural similarity. Our approach takes different similarities into one whole, as a similarity cube. By cutting operation, similarity vectors are obtained, which form the similarity space, and by this way, mapping discovery can be converted into binary classification. Support vector machine (SVM) has good generalization ability and can obtain best compromise between complexity of model and learning capability when solving small samples and the nonlinear problem. Because of the said reason, we employ SVM in our approach. For making full use of the information of ontology, our implementation and experimental results used a common dataset to demonstrate the effectiveness of the mapping approach. It ensures the recall ration while improving the quality of mapping results. 相似文献
997.
Shyi‐Kae Yang 《Asian journal of control》2012,14(2):564-571
This paper presents a new strategy for suppressing the windup effect caused by actuator saturation in proportional–integral–derivative (PID) controlled systems. In the proposed approach, the windup effect is modeled as an external disturbance imported to the PID controller and an observer‐based auxiliary controller is designed to minimize the difference between the controller output signal and the system input signal in accordance with an H‐infinite optimization criterion. It is shown that the proposed anti‐windup (AW) scheme renders the performance of the controlled system more robust toward the effects of windup than conventional PID AW schemes and provides a better noise rejection capability. In addition, the proposed PID AW scheme is system independent and is an explicit function of the parameters of the original PID controller. As a result, the controller is easily implemented using either digital or analog circuits and facilitates a rapid, on‐line tuning of the controller parameters as required in order to prevent the windup effect. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
998.
Economic contribution rate of education (ECRE) is the key factor of education economics. This article selected China, South Korea, United States and other countries for a total of 15 samples, and put the data of the same period under the framework of soft computing, to simulate the production chain of “education–potential human capital–actual human capital–economic growth”. The basic idea is: Firstly, 15 countries are softly categorized according to the level of science and technology (S&T) progress. Secondly, potential human capital and actual human capital establish the internal correlation (fuzzy mapping) in the same classification, and we conceptualize actual human capital as one production factor, joined with the other two production factors, fixed asset and land, to set up the fuzzy mapping to economic growth., and then calculate economic contribution rate of education of China and foreign by two fuzzy mapping of them. Thirdly, this paper analyzes the present state and differences in the development of education between China and foreign according to different ECRE, and offers proposals for promoting the education in China. 相似文献
999.
Large-scale data-intensive cloud computing with the MapReduce framework is becoming pervasive for the core business of many
academic, government, and industrial organizations. Hadoop, a state-of-the-art open source project, is by far the most successful
realization of MapReduce framework. While MapReduce is easy- to-use, efficient and reliable for data-intensive computations,
the excessive configuration parameters in Hadoop impose unexpected challenges on running various workloads with a Hadoop cluster
effectively. Consequently, developers who have less experience with the Hadoop configuration system may devote a significant
effort to write an application with poor performance, either because they have no idea how these configurations would influence
the performance, or because they are not even aware that these configurations exist. There is a pressing need for comprehensive
analysis and performance modeling to ease MapReduce application development and guide performance optimization under different
Hadoop configurations. In this paper, we propose a statistical analysis approach to identify the relationships among workload
characteristics, Hadoop configurations and workload performance. We apply principal component analysis and cluster analysis
to 45 different metrics, which derive relationships between workload characteristics and corresponding performance under different
Hadoop configurations. Regression models are also constructed that attempt to predict the performance of various workloads
under different Hadoop configurations. Several non-intuitive relationships between workload characteristics and performance
are revealed through our analysis and the experimental results demonstrate that our regression models accurately predict the
performance of MapReduce workloads under different Hadoop configurations. 相似文献
1000.
Chengcheng Zhou Kang Xue Lidan Gou Chunfang Sun Gangcheng Wang Taotao Hu 《Quantum Information Processing》2012,11(6):1765-1773
In this paper, a 3?×?3-matrix representation of Birman?CWenzl?CMurakami (BWM) algebra has been presented. Based on which, unitary matrices A(??, ?? 1, ?? 2) and B(??, ?? 1, ?? 2) are generated via Yang?CBaxterization approach. A Hamiltonian is constructed from the unitary B(??, ??) matrix. Then we study Berry phase of the Yang?CBaxter system, and obtain the relationship between topological parameter and Berry phase. 相似文献