A relational approach to defining and implementing transformations between metamodels

The Model-Driven Architecture initiative of the OMG promotes the idea of transformations in the context of mapping from platform independent to platform specific models. Additionally, the popularity of XML and the wide spread use of XSLT has raised the profile of model transformation as an important technique for computing. In fact, computing may well be moving to a new paradigm in which models are considered first class entities and transformations between them are a major function performed on those models. This paper proposes an approach to defining and implementing model transformations which uses metamodelling patterns to capture the essence of mathematical relations. It shows how these patterns can be used to define the relationship between two different metamodels. A goal of the approach is to enable complete specifications from which tools can be generated. The paper describes implementations of the examples, which have been partially generated from the definitions using a tool generation tool. A number of issues emerge which need to be solved in order to achieve the stated goal; these are discussed.     

Development of an Internet-based intelligent design support system for rolling element bearings

This paper presents a novel approach to developing an intelligent agile design system for rolling bearings based on artificial intelligence (AI), Internet and Web technologies and expertise. The underlying philosophy of the approach is to use AI technology and Web-based design support systems as smart tools from which design customers can rapidly and responsively access the systems' built-in design expertise. The approach is described in detail with a novel AI model and system implementation issues. The major issues in implementing the approach are discussed with particular reference to using AI technologies, network programming, client-server technology and open computing of bearing design and manufacturing requirements.     

Transputer simulation of decoupled electrical circuits

This paper describes a parallel simulation of an electrical circuit using the Transmission Line Modelling (TLM) method. The TLM method is used to decouple the circuit into sub-circuits which are then simulated concurrently in a parallel processing system. This approach not only simplifies the circuit formulation process but also reduces the overall computing time of the circuit simulation when compared with traditional sequential method. The techniques for decoupling the circuit and implementing the parallel algorithm are described. The method is demonstrated in an electrical circuit simulation. Comparison of the computing time and simulated results with the sequential approach confirms the computing efficiency and accuracy of the proposed method.     

A study of graphics hardware accelerated particle swarm optimization with digital pheromones

Programmable Graphics Processing Units (GPUs) have lately become a promising means to perform scientific computations. Modern GPUs have proven to outperform the number of floating point operations when compared to traditional Central Processing Units (CPUs) through inherent data parallel architecture and higher bandwidth capabilities. They allow scientific computations to be performed without noticeable degradation in accuracy in a fraction of the time compared to traditional CPUs at substantially reduced costs, making them viable alternatives to expensive computer clusters or workstations. GPU programmability however, has fostered the development of a variety of programming languages making it challenging to select a computing language and use it consistently without the pitfall of being obsolete. Some GPU languages are hardware specific and are designed to rake in performance boosts when used with their host GPUs (e.g., Nvidia Cuda). Others are operating system specific (e.g., Microsoft HLSL). A few are platform agnostic lending themselves to be used on a workstation with any CPU and a GPU (e.g., GLSL, OpenCL).Of a number of companies and organizations that implement formal optimization into their processes, only a few utilize GPUs. It is either because the others are either vested much into CPU based computing or they are not fully aware of the benefits of implementing population based optimization routines in GPUs. Literature shows a large number of research publications specifically in the field of optimization utilizing GPUs. However, most of them are limited to a specific GPU hardware or addressed specific problems. The diversity in current GPU hardware and software APIs present overwhelming number of choices making it challenging to decide where and how to begin transitioning to GPU based computing, impeding promising computing avenues that relatively is very cost effective. In this paper, the authors precisely intend to address some of these issues by broadly classifying GPU APIs into three categories: 1) Hardware vendor dependent GPU APIs, 2) Graphical in context APIs, and 3) Platform agnostic APIs. Prior work by the authors demonstrated the capability of digital pheromones within Particle Swarm Optimization (PSO) for searching n-dimensional design spaces with improved accuracy, efficiency and reliability in serial and parallel CPU computing environments. To study the impact of GPUs, the authors have taken this digital pheromone variant of PSO and implemented it on three GPU APIs, each representing a category listed above, in a simplistic sense – delegate unconstrained explicit objective function evaluations to GPUs. While this approach itself cannot be considered novel, the takeaways from implementing it on different GPU APIs provided a wealth of information that the authors believe can help optimization companies and organizations make informed decisions in implementing GPUs in their processes.     

一种基于移动Agent的动态计算资源模型的研究

计算资源的动态部署为分布计算提供灵活、高效的解决方案，针对移动环境，当前的一些研究工作还存在局限性．以移动Agent技术为基础，考虑到移动环境的动态性、不确定性，提出了动态计算资源部署模型及自主性能优化算法，较好地解决了移动环境的资源部署和性能优化问题．结果表明其方法是通用的、可行的、有效的．     

基于多智能体的多机群网格模型

在由多计算机机群构成的网格环境下,为了实现数据并行型计算,提出了一个基于多智能体机制的网格开发模型.给出了由多计算机机群组成的网格、逻辑计算机机群、数据并行型计算和一系列Agent的定义.利用管理智能体、独立计算智能体、协同计算智能体以及协同计算组之间的协同计算机制来实现数据并行型计算.描述了网格计算过程.实践表明,该模型有效地适应了多机群网格环境的异构性、动态性等特性,提高了计算资源的利用率.该模型适合于基于网格的并行型计算.     

移动Intranet计算模型

现有的Ｉｎｔｒａｎｅｔ计算不能支持移动计算。利用移动代理技术建立了移动Ｉｎｔｒａｎｅｔ计算模型．探讨了在Ｉｎｔｒａｎｅｔ上实现移动代理计算模式的若干问题。     

Ergodic Quantum Computing

We propose a (theoretical) model for quantum computation where the result can be read out from the time average of the Hamiltonian dynamics of a 2-dimensional crystal on a cylinder.The Hamiltonian is a spatially local interaction among Wigner–Seitz cells containing six qubits. The quantum circuit that is simulated is specified by the initialization of program qubits. As in Margolus Hamiltonian cellular automaton (implementing classical circuits), a propagating wave in a clock register controls asynchronously the application of the gates. However, in our approach all required initializations are basis states. After a while the synchronizing wave is essentially spread around the whole crystal. The circuit is designed such that the result is available with probability about 1/4 despite of the completely undefined computation step. This model reduces quantum computing to preparing basis states for some qubits, waiting, and measuring in the computational basis. Even though it may be unlikely to find our specific Hamiltonian in real solids, it is possible that also more natural interactions allow ergodic quantum computing.PACS:03.67.Lx     

Making a case for BPC [Broadening Participation in Computing]

BPC program aims to significantly increase the number of students who are US citizens and permanent residents receiving postsecondary degrees in the computing disciplines. The BPC program seeks to engage the computing community in developing and implementing innovative methods to improve recruitment and retention of these students at the undergraduate and graduate levels. The NSF programs take a research approach to addressing the issues associated with broadening participation in computing. However there are few places where this type of research can be disseminated so that it would impact the computing community. This "Broadening Participation in Computing" series provides a forum for computer science researchers to present their findings and offer solutions that address these problems.     

开放普适计算环境的实现

开放系统已经成为当今计算机界广泛倡导并积极遵循的策略。从开放系统的基本特征出发，导出描述开放系统的轮廓框架(AUSPICE)，通过对轮廓中各个组成部分，选用一定的标准就可以实现一个开放系统。但实现一个完全的开放系统是一个长期的过程，而且对于具体应用环境和需求．其实现过程各有不同。本文针对普适计算环境，首先分析了开放性对于普适计算环境的重要性和必然性，同时针对普适计算环境的特点，对开放系统的轮廓框架扩充为AUSPICAE，最后提出了适合普适计算环境的开放系统实现过程模型。     

Control of resource-intensive computations under uncertainty. I. Multiparametric model

A complex of models, algorithms and programs designed to control a high-performance heterogeneous specialized computing system that executes heterogeneous tasks is presented. A multi-parametric model designed to control processing of resource-intensive heterogeneous computational tasks that can be parallelized with respect to data is given. The model relies on operation research technique and uses the principle of guaranteed result for control under objective uncertainty. During scheduling, maximin estimates of unknown variables (time in the system, processing duration, etc.) are calculated at each check point and used to form scheduling control commands. This approach allowed implementing a fundamentally new service discipline in practice that implies less resource-intensive tasks to be solved first.     

隐马尔可夫模型的一种有区分力的反向传播训练方法

研究隐马尔可夫模型(HMM)的一种有区分力的训练方法.在多层前向神经网络的 框架中实现了HMM的前向概率计算.基于这一框架,利用偏导数的反向传播计算方法,通 过梯度上升的优化过程来实现互信息的最大化,从而对HMM进行有区分力的训练.这一 训练方法被称之为HMM的反向传播训练方法.此外,还设计了一个用以实现这一训练方 法的在数值计算上具有强鲁棒性的算法.语音识别的实验结果证实了这一训练方法的优越 性.     

DartGrid II: a semantic grid platform for ITS

Intelligent transportation systems offer an alternative approach to solving many problems by implementing advances in information, Internet, communication, and cybernetics technologies. Grid computing can support traffic data semantization, resource sharing, ITS subsystem cooperation, and global-scale distributed computing that connects all kinds of resources. We are currently using grid technology to build DartGrid II, a semantic ITS platform to support resource sharing, service flow management, and cross-domain cooperation.     

Model management in organizations

The premise that the personal computer/spreadsheet explosion will result in the evolution of model management within organizations is explored. The authors use Nolan's stage model of organizational data processing activity as a basis for discussing the nature of change in organizations as local computing capability proliferates. The mainframe era resulted in the recognition of data as a resource and gave rise to data administration. The authors expect that the personal computer era and the accompanying spreadsheet explosion will lead to the recognition of models as a valuable and manageable resource. The role of model administration within organizations is discussed as are software tools for supporting this functional activity. The information resource encyclopedia, an extension of the traditional data dictionary concept, and the model management system are introduced as integral components for supporting model administration. An example is presented to suggest an integrative approach for implementing an MMS in a spreadsheet environment.     

单调比率(RM)调度算法及应用

介绍了任务死线不大于其周期的任务集调度条件分析及算法实现。这种约束条件放松, 有利于周期与非周期任务混合模型调度。同时,分析了以往调度算法中单调比率调度算法约束条件, 并指明了计算时间复杂度的缺点。因而,在RM算法基础之上提出一种实时系统调度算法及实现流 程图,并对提出的现场级实时调度算法进行了对比测试。     

A comprehensive peer‐to‐peer characterization model

A peer‐to‐peer (P2P) characterization model is proposed in this paper. The purposes of this model are (a) to describe through abstraction the behavior and capability of P2P computing independent of any specific application, and (b) to lead to a cost model of P2P computing. Our approach is based on abstracting the service driven nature of P2P computing separate and distinct from its implementation. This supports the first purpose. Next, we consider the integration of the two aspects. This supports the second purpose. A secondary contribution of our work is a cost model. The cost model is applied to indexing, discovery and resource utilization services. In addition, the characterization model and cost model are applied to a JXTA‐based P2P application. Copyright © 2006 John Wiley & Sons, Ltd.     

XML文档相似性的仿真研究

XML文档相似性的计算是XML文档分类中的一个难题。文中描述了一种基于结构的方法，通过序列化模式挖掘方法，挖掘出两个文档之间的最大相似路径，从而可以通过计算最大相似的路径的节点数目和所有路径的节点数目的比值，得到两个文档之间的相似度。文章提出了一种新的最小化XML文档的方法，并且综合考虑了文档节点的语义相似度和结构相似度，从而进一步地提高了计算文档相似度的精度。实验表明，该方法有着良好的应用前景。     

DES算法密码计算构件的FPGA实现

文章通过分析金融CPU卡在消费交易流程的密码计算模型,结合射频IC卡的特点,设计了等价密码计算模型,并用现场可编程门阵列(FPGA)实现。     

异构混合云服务下的多任务算力度量方法

异构网络中混合云服务下的任务数据量复杂程度较高、数据维度高,影响多任务算力度量的效率及完成率,提出了异构混合云服务下的多任务算力度量方法。分析异构混合云服务系统,获取多任务算力数据,依据获取结果从中提取多任务算力特征集。利用构建的度量模型对多任务算力特征进行标识及量化,通过对模型及特征的实例相似性计算,建立多任务算力度量矩阵,根据该矩阵实现多任务算力度量。实验结果表明：通过对该方法实施度量性能及度量效果对比测试,验证了该方法对任务算力度量的耗时短,多任务算力度量完成率较高。     

一个基于OGSA规范的网格计算过程表示模型

提出一个基于网格服务树的网格计算过程的表示模型。对网格服务、网格计算过程、网格服务树、网格给出了形式化的定义,描述了一个网格计算过程表示模型,并给出了实现的机制和算法,最后给出利用Webservice技术的模拟试验的方法。分析和实验结果表明,该模型有效地表示了基于WAN或Internet的网格计算过程,符合OGSA规范。该模型适合网格系统的构建、监测以厦基于Webservice机制的Internet的QoS管理等应用领域。