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1.
The number of databases that are accessible over networks within organizations is increasing. This paper presents a methodology for automatically converting the data in these databases into a useful knowledge base of case-based semantic networks that can be accessed through a browsing facility. A parallel processing strategy has been implemented for this knowledge acquisition process to support its scalability to large databases. This methodology has potential application in the development of organizational intranets. It can also be used for retrospective browsing of the context of interesting patterns discovered by data mining. The database examples used in this paper are from clinical laboratories that provide data to a hospital infection control committee. Even though the results presented here use a single domain, the methodology can be used with no changes to explore the construction of multidomain knowledge bases.  相似文献   

2.
Abstract. A new parallel hybrid decision fusion methodology is proposed. It is demonstrated that existing parallel multiple expert decision combination approaches can be divided into two broad categories based on the implicit decision emphasis implemented. The first category consists of methods implementing computationally intensive decision frameworks incorporating a priori information about the target task domain and the reliability of the participating experts, while the second category encompasses approaches implementing group consensus without assigning any importance to the reliability of the experts and ignoring other contextual information. The methodology proposed in this paper is a hybridisation of these two approaches and has shown significant performance enhancements in terms of higher overall recognition rates along with lower substitution rates. Detailed analysis using two different databases supports this claim. Received January 19, 1999 / Revised March 20, 2000  相似文献   

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In the paper the design methodology and stability analysis of parallel distributed fuzzy model based predictive control is presented. The idea is to design a control law for each rule of the fuzzy model and blend them together. The proposed control algorithm is developed in state space domain and is given in analytical form. The analytical form brings advantages in comparison with optimization based control schemes especially in the sence of realization in real-time. The stability analysis and design problems can be viewed as a linear matrix inequalities problem. This problem is solved by convex programming involving LMIs. In the paper a sufficient stability condition for parallel distributed fuzzy model-based predictive control is given. The problem is illustrated by an example on magnetic suspension system.  相似文献   

5.
微控制器中ALU与移位逻辑的设计与改进   总被引:2,自引:0,他引:2       下载免费PDF全文
文章结合8位微控制器IP软核的设计,分析了指令系统的功能与特点,在算法级上对其处理器中数据路径进行了合理的调整与优化,并提出一种将ALU与移位逻辑并行设计的方法。较之于传统的串行设计方法而言,这种并行设计方法不仅描述简单,而且综合得到的电路降低了功耗,具有更快的运算速度,同时并不增加资源消耗。  相似文献   

6.
并行计算正成为科学和工程计算中的一个新趋势。将采用区域分裂技术的并行有限元方法应用于工作站机群的分布式并行环境。提出了基于单元区域分裂的共轭梯度并行算法。在工作站机群上对坝体结构进行求解,对其并行性能进行分析。  相似文献   

7.
基于构件的框架开发方法及其特定域应用   总被引:12,自引:0,他引:12  
吴明晖  应晶  何志均 《计算机工程》1999,25(10):86-87,92
传统的软件开发方法在面向的软件系统开发过程中难以支持理用性,针对此问题,提出了一种基于构件的框架开发方法FCDM,主要讨论领域分析,领域框架的划分,领域构件的提取及应用系统的生成关键过程,并给出在特定领域中的应用实例。  相似文献   

8.
Study on Parallel Computing   总被引:5,自引:0,他引:5       下载免费PDF全文
In this paper, we present a general survey on parallel computing. The main contents include parallel computer system which is the hardware platform of parallel computing, parallel algorithm which is the theoretical base of parallel computing, parallel programming which is the software support of parallel computing. After that, we also introduce some parallel applications and enabling technologies. We argue that parallel computing research should form an integrated methodology of "architecture algorithm programming application". Only in this way, parallel computing research becomes continuous development and more realistic.  相似文献   

9.
Formulation of qualitative models for complex decision problems exhibiting less structure, more imprecision and uncertainty is not adequately addressed in DSS research. Typical characteristics and requirements of such problems prohibit the development of DSS using knowledge based system development methodologies. This paper presents a methodology for formulation of qualitative models using fuzzy logic to handle the imprecision and uncertainty in the problem domain. The problem domain, in this methodology, is represented using problem-solving knowledge, environmental knowledge, and control knowledge components. A high level non-procedural language for representing these components of knowledge is illustrated using a project selection and resource allocation problem. The paper also describes the implementation of a prototype decision support environment based on this methodology.  相似文献   

10.
并行软件功能规约的组合语义方法   总被引:3,自引:0,他引:3  
文章提出了一种将代数语义、Hoars逻辑和UNITY逻辑集成在一起描述并行软件功能规约的方法。其目的在于充分发挥并集成代数语义描述抽象数据类型、Hoars逻辑描述功能、UNITY逻辑描述并行程序性质的优点。表示形式有利于规约的分解、细化和验证。  相似文献   

11.
该文基于分布式并行计算机系统,对一类多层二维二相流油藏数值模拟问题给出了3种任务划分策略-"卷帘"方式、区域分解方式和"卷帘"与区域分解结合的方式,对它们进行了比较,提出了减少求解时间、利于负载均衡和提高并行性能的任务划分方法,并实际应用于有多达72万个网格节点的大规模油藏模拟问题.实算结果表明,该策略划分产生的并行求解任务均衡,有利于加速比的提高.该方法也适用于区域或数据并行的任务划分问题.  相似文献   

12.
This paper presents parallel computational strategies to implement explicit nonlinear finite element analysis code onto distributed memory parallel computers for solving large-scale problems in structural dynamics. Implementation details on both homogeneous and heterogeneous parallel processing environments are considered in detail in this paper. Implementation of an explicit nonlinear finite element dynamic analysis code on homogeneous systems is discussed first and this is later moved onto heterogeneous systems. Domain decomposition with explicit message passing is preferred for parallel implementation. The message passing implementation in the parallel algorithm is based on MPI (Message Passing Interface) libraries. Implementation aspects of overlapped, non-overlapped domain decomposition techniques, Dynamic Task Allocation (DTA) and clustering techniques for DTA and their relative merits are presented. The interprocessor communications are optimised by overlapping with computations to improve the performance of the domain decomposition based explicit dynamic analysis finite element code.The issues related to implementation of finite element code for nonlinear dynamic analysis on heterogeneous parallel computing environment are later presented. A new dynamic load-balancing algorithm is developed for this purpose and it is integrated with the domain decomposition based parallel explicit finite element code to test our algorithms on a coarse grain heterogeneous cluster of workstations. Numerical experiments have been carried out on PARAM-10000, an Indian parallel computer and also on cluster of Unix workstations.  相似文献   

13.
In this paper, a design methodology for synthesizing efficient parallel algorithms and VLSI architectures is presented. A design process starts with a problem definition specified in the parallel programming language Crystal and is followed by a series of program transformations in Crystal, each aiming at optimizing the target design for a specific purpose. To illustrate the design methodology, a set of design methods for deriving systolic algorithms and architectures is given and the use of these methods in the design of a dynamic programming solver is described. The design methodology, together with this particular set of design methods, can be viewed as a general theory of systolic designs (or multidimensional pipelines). The fact that Crystal is a general purpose language for parallel programming allows new design methods and synthesis techniques, properties and theorems about problems in specific application domains, and new insights into any given problem to be integrated readily within the existing design framework.  相似文献   

14.
In this article we present a high-performance computing framework for advanced flow simulation and its application to wind energy based on the residual-based variational multiscale (RBVMS) method and isogeometric analysis. The RBVMS formulation and its suitability and accuracy for turbulent flow in a moving domain are presented. Particular emphasis is placed on the parallel implementation of the methodology and its scalability. Two challenging flow cases were considered: the turbulent Taylor–Couette flow and the NREL 5 MW offshore baseline wind turbine rotor at full scale. In both cases, flow quantities of interest from the simulation results compare favorably with the reference data and near-perfect linear parallel scaling is achieved.  相似文献   

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The arrival of multicore systems, along with the speed‐up potential available in graphics processing units, has given us unprecedented low‐cost computing power. These systems address some of the known architecture problems but at the expense of considerably increased programming complexity. Heterogeneity, at both the architectural and programming levels, poses a great challenge to programmers. Many proposals have been put forth to facilitate the job of programmers. Leaving aside proposals based on the development of new programming languages because of the effort this represents for the user (effort to learn and reuse code), the remaining proposals are based on transforming sequential code into parallel code, or on transforming parallel code designed for one architecture into parallel code designed for another. A different approach relies on the use of skeletons. The programmer has available set of parallel standards that comprise the basis for developing parallel code while programming sequential code. In this context, we propose a methodology for developing an automatic source‐to‐source transformation in a specific domain. This methodology is instantiated in a framework aimed at solving dynamic programming problems. Using this framework, the final user (a physician, mathematician, biologist, etc.) can express her problem using an equation in Latex, and the system will automatically generate the optimal parallel code for homogeneous or heterogeneous architectures. This approach allows for great portability toward these new emerging architectures and for great productivity, as evidenced by the computational results.Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

17.
基于多层油藏问题负载均衡的并行任务划分   总被引:1,自引:0,他引:1  
舒继武  赵金熙  周维四  张德富 《软件学报》1999,10(10):1061-1066
该文基于分布式并行计算机系统,对一类多层二维二相流油藏数值模拟问题给出了3种任务划分策略—“卷帘”方式、区域分解方式和“卷帘”与区域分解结合的方式,对它们进行了比较,提出了减少求解时间、利于负载均衡和提高并行性能的任务划分方法,并实际应用于有多达72万个网格节点的大规模油藏模拟问题.实算结果表明,该策略划分产生的并行求解任务均衡,有利于加速比的提高.该方法也适用于区域或数据并行的任务划分问题.  相似文献   

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19.
We have developed a methodology for predicting the performance of parallel algorithms on real parallel machines. The methodology consists of two steps. First, we characterize a machine by enumerating the primitive operations that it is capable of performing along with the cost of each operation. Next, we analyze an algorithm by making a precise count of the number of times the algorithm performs each type of operation. We have used this methodology to evaluate many of the parallel sorting algorithms proposed in the literature. Of these, we selected the three most promising, Batcher's bitonic sort, a parallel radix sort, and a sample sort similar to Reif and Valiant's flashsort, and implemented them on the connection Machine model CM-2. This paper analyzes the three algorithms in detail and discusses the issues that led us to our particular implementations. On the CM-2 the predicted performance of the algorithms closely matches the observed performance, and hence our methodology can be used to tune the algorithms for optimal performance. Although our programs were designed for the CM-2, our conclusions about the merits of the three algorithms apply to other parallel machines as well. Received April 1996, and in final form June 1996.  相似文献   

20.
This paper presents a general model to define, measure and predict the efficiency of applications running on heterogeneous parallel computer systems. Using this framework, it is possible to understand the influence that the heterogeneity of the hardware has on the efficiency of an algorithm. This methodology is used to compare an existing parallel genetic algorithm with a new adaptive parallel model. All the performance measurements were taken in a loosely coupled cluster of processors.  相似文献   

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