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41.
The execution of composite Web services with WS-BPEL relies on externally autonomous Web services. This implies the need to
constantly monitor the running behavior of the involved parties. Moreover, monitoring the execution of composite Web services
for particular patterns is critical to enhance the reliability of the processes. In this paper, we propose an aspect-oriented
framework as a solution to provide monitoring and recovery support for composite Web services. In particular, this framework
includes 1) a stateful aspect based template, where history-based pointcut specifies patterns of interest cannot be violated within a range, while advice specifies the associated recovery action; 2) a tool support for runtime monitoring and recovery based on aspect-oriented
execution environment. Our experiments indicate that the proposed monitoring approach incurs minimal overhead and is efficient.
This work is supported by the National Natural Science Foundation of China under Grant Nos. 60673112, 90718033, the National
Basic Research 973 Program of China under Grant No. 2009CB320704, and the High-Tech Research and Development 863 Program of
China under Grand Nos. 2006AA01Z19B, 2007AA010301. 相似文献
42.
In this paper, we investigate the locally and globally adaptive synchronization problem for an uncertain complex dynamical network with time-varying coupling delays based on the decentralized control. The coupling terms here are bounded by high-order polynomials with known gains that are ubiquitous in a large class of complex dynamical networks. We generalize the usual technology of searching for an appropriate coordinates transformation to change the network dynamics into a series of decoupled lower-dimensional systems. Several adaptive synchronization criteria are derived by constructing the Lyapunov-Krasovskii functional and Barbalat lemma, and the proposed criteria are simple in form and convenient for the practical engineering design. Numerical simulations illustrated by a nearest-neighbor coupling network verify the effectiveness of the proposed synchronization scheme. 相似文献
43.
With the expansion of smart grid and Internet of things (IoT) technology, edge computing has a wide variety of applications in these domains. The criteria for real-time monitoring and accuracy are particularly high in the field of online real-time monitoring of electricity lines. Based on edge technology, high-quality real-time monitoring can be performed for transmission lines using image processing techniques. Therefore, we propose an image denoising method, which can learn clean images using a stream-based generative model. The stream model uses a two-stage approach in the network to handle the different training periods of denoising separately. Experimental results show that the proposed method has good denoising performance. 相似文献
44.
As the traditional semiconductor complementary metal oxide semiconductor (CMOS) integrated circuit technology gradually approaches the limit of Moore's Law, quantum computing, as a new system computing technology,with the potential for higher computing speed and lower power consumption, is getting more and more attention from governments and research institutions around the world. For instance, the United States (US) government is adopting a bunch of bills to deploy new quantum information processing technology. The European Union's “quantum declaration" plans to realize customized quantum computers with more than 100 qubits in the next 10 years. The Chinese government also provides strong support for quantum computer research through the project of National Science and Technology Major Projects. In the business field, major companies such as International Business Machines (IBM) Corporation, Intel, Google, Alibaba, Huawei, Baidu, etc. , have joined the “quantum supremacy" competition in order to seize the initiative in the future information field. Facing the rapid development trend of quantum computing, we believe that we should refer to the classical computer industry in the early stage, form an industrial system, and develop the quantum computing industry. We should also use the scientific system engineering method to carry out the research and development of the quantum computer and establish the ecological environment of the quantum computer industry with the demand as the traction, so as to better serve the development of the national economy. 相似文献
45.
We review the literature on approximate dynamic programming, with the goal of better understanding the theory behind practical algorithms for solving dynamic programs with continuous and vector-valued states and actions and complex information processes. We build on the literature that has addressed the well-known problem of multidimensional (and possibly continuous) states, and the extensive literature on model-free dynamic programming, which also assumes that the expectation in Bellman’s equation cannot be computed. However, we point out complications that arise when the actions/controls are vector-valued and possibly continuous. We then describe some recent research by the authors on approximate policy iteration algorithms that offer convergence guarantees (with technical assumptions) for both parametric and nonparametric architectures for the value function. 相似文献
46.
AO Jun MA ChunBo AO FaLiang & LIAO GuiSheng College of Information Communication Guilin University of Electronic Technology Guilin China National Key Laboratory of Electromagnetic Environment QingDao National Lab of Radar Signal Processing Xidian University Xi’an 《中国科学:信息科学(英文版)》2011,(7):1481-1490
By studying the super-orthogonal space-time coding designs for 2 transmit antennas and superquasi orthogonal space-time coding designs for 4 transmit antennas,a novel super-orthogonal space-time coding design for 4 transmit antennas is proposed.By exploiting the inherent structure association between OSTBC and QOSTBC,the proposed schemes can obtain the full-rate and good performance while keeping the coding complexity as super-orthogonal space-time coding schemes for 2 transmit antennas.Simulation results d... 相似文献
47.
本文提出了一种多功能网络监控与防御系统。文中根据网络自身的结构,从骨干层、汇聚层、接入层三个层次分析,采用三层设计模式,它们相互独立又相互协作,共同构成高性能、多层次、多功能综合解决方案。形成深度防御体系,最大限度地保护企业和组织的网络安全。 相似文献
48.
Study of image enhancement shows that the quality of image heavily relies on human visual system. In this paper, we apply this fact effectively to design a new image enhancement method for medical images that improves the detail regions. First, the eye region of interest (ROI) is segmented; then the Un-sharp Masking (USM) is used to enhance the detail regions. Experiments show that the proposed method can effectively improve the accuracy of medical image enhancement and has a significant effect. 相似文献
49.
A new method is proposed for surface construction on irregular quad meshes as extensions to uniform B-spline surfaces. Given a number of control points, which form a regular or irregular quad mesh, a weight function is constructed for each control point. The weight function is defined on a local domain and is C1 continuous. Then the whole surface is constructed by the weighted combination of all the control points. The property of the new method is that the surface is defined by piecewise Cl bi-cubic rational parametric polynomial with each quad face. It is an extension to uniform B-spline surfaces in the sense that its definition is an analogy of the B-spline surface, and it produces a uniform bi-cubic B-spline surface if the control mesh is a regular quad mesh. Examples produced by the new method are also included. 相似文献
50.
叙述了MIS在厦门市轮渡公司的人事和月票管理中的实践和应用。首先从系统的组成、基本原理、基本功能阐述了MIS在人事管理中的实践 ,并取得既方便又快捷、且准确的效果 ;然后通过对轮渡TM卡的构成、基本功能、应用效果进行了阐述 ,证明了TM卡最适用于轮渡作为月票使用。在当今社会 ,MIS已成为现代企业不可缺少的组成部分 ,是企业升级的重要标志。 相似文献