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121.
K. Geihs P. Barone F. Eliassen J. Floch R. Fricke E. Gjorven S. Hallsteinsen G. Horn M. U. Khan A. Mamelli G. A. Papadopoulos N. Paspallis R. Reichle E. Stav 《Software》2009,39(4):385-422
Driven by the emergence of mobile and pervasive computing there is a growing demand for context‐aware software systems that can dynamically adapt to their run‐time environment. We present the results of project MADAM that has delivered a comprehensive solution for the development and operation of context‐aware, self‐adaptive applications. The main contributions of MADAM are (a) a sophisticated middleware that supports the dynamic adaptation of component‐based applications, and (b) an innovative model‐driven development methodology that is based on abstract adaptation models and corresponding model‐to‐code transformations. MADAM has demonstrated the viability of a general, integrated approach to application‐level adaptation. We discuss our experiences with two real‐world case studies that were built using the MADAM approach. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
122.
Application frameworks are a powerful means to reduce software development costs while improving quality. However, at the same time they are difficult to select and understand, as well as hard to learn, use, and debug effectively and efficiently. In this paper we report the story of eConference, a distributed conferencing system that was developed as part of a broader research effort. Here we discuss the lessons learned from the evolution of our conferencing tool over four generations, which have been necessary to find good frameworks and build a flexible distributed tool. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
123.
Michael?DeBoleEmail author Ramakrishnan?Krishnan Varsha?Balakrishnan Wenping?Wang Hong?Luo Yu?Wang Yuan?Xie Yu?Cao N.?Vijaykrishnan 《International journal of parallel programming》2009,37(4):417-431
Degradation of device parameters over the lifetime of a system is emerging as a significant threat to system reliability.
Among the aging mechanisms, wearout resulting from Negative Bias Temperature Instability (NBTI) is of particular concern in
deep submicron technology generations. While there has been significant effort at the device and circuit level to model and
characterize the impact of NBTI, the analysis of NBTI’s impact at the architectural level is still at its infancy. To facilitate
architectural level aging analysis, a tool capable of evaluating NBTI vulnerabilities early in the design cycle has been developed
that evaluates timing degradation due to NBTI. The tool includes workload-based temperature and performance degradation analysis
across a variety of technologies and operating conditions, revealing a complex interplay between factors influencing NBTI
timing degradation. 相似文献
124.
In this paper we discuss regularization of images that take their value in matrix Lie groups. We describe an image as a section
in a principal bundle which is a fibre bundle where the fiber (the feature space) is a Lie group. Via the scalar product on
the Lie algebra, we define a bi-invariant metric on the Lie-group manifold. Thus, the fiber becomes a Riemannian manifold
with respect to this metric. The induced metric from the principal bundle to the image manifold is obtained by means of the
bi-invariant metric. A functional over the space of sections, i.e., the image manifolds, is defined. The resulting equations
of motion generate a flow which evolves the sections in the spatial-Lie-group manifold. We suggest two different approaches
to treat this functional and the corresponding PDEs. In the first approach we derive a set of coupled PDEs for the local coordinates
of the Lie-group manifold. In the second approach a coordinate-free framework is proposed where the PDE is defined directly with respect to the Lie-group elements. This is a parameterization-free
method. The differences between these two methods are discussed. We exemplify this framework on the well-known orientation
diffusion problem, namely, the unit-circle S
1 which is identified with the group of rotations in two dimensions, SO(2). Regularization of the group of rotations in 3D and 4D, SO(3) and SO(4), respectively, is demonstrated as well.
相似文献
Nir SochenEmail: |
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结合中国电信行业信息化建设的实际需求,引入JavaEE架构体系,提出一种在JavaEE平台上开发大型电信客户关系管理数据持久层的方法。通过门面模式、VO模式和DAO模式在SpringJDBC架构中的应用,实现持久层之间的松散耦合,使整个系统具备良好的稳定性、可伸缩性和可扩展性。 相似文献
128.
阐述面向对象的非线性有限元软件框架设计,在前人成果的基础上,力求软件框架更灵活、更完善。采用模型分析方法与有限元模型分离的方式,明确描述各类之间的依赖关系以及相互之间的传递消息过程,建立非线性有限元软件的框架结构。增加有限元软件的模块化、代码的重用性和易扩展性,解决长期以来存在于非线性有限元开发的一个重要难题。 相似文献
129.
利用J2EE技术开发Web应用系统时经常需要编写大量代码来处理组织机构管理、权限管理、日志管理等基础业务,对于大量结构相似的业务处理页面仍需要手工编码,导致开发工作量增大,开发周期变长。针对这些问题,设计并实现了一个Web应用基础业务框架,该框架提供相关基础业务模块供开发Web应用系统使用,使用自动化生成工具来生成Web应用系统中的大量数据维护页面。工程实践表明,该框架能够较大程度地提高Web应用系统的开发效率,缩短开发周期,增强系统的可扩展性。 相似文献
130.