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产品性能因素描述构架的建立   总被引:1,自引:1,他引:1  
产品性能作为产品设计的核心,贯穿产品设计的整个过程,抓住产品设计的共性,无疑是产品设计的关键。采用知识工程中的因素空间理论作为理论支撑,基于三层调和功能基础的统一功能分类表达,构建了以统一功能表达分类为维名称的产品性能因素描述构架,并对此构架空间的属性进行了理论分析。为了更好地理解构架空间的概念,描述了具体产品按照性能因素纳入构架空间的5个主要步骤。产品性能因素描述构架的建立,不仅使产品在性能级抽象层次上获得了表面的空间,更重要的是它为产品性能的量化提供了坐标参考,也为分布式资源环境下基于性能驱动的产品检索提供了知识获取依据,从而使CAD技术有望在性能驱动的产品概念设计阶段得到应用。  相似文献   

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Performance is one of the key problems in either high performance computing or GRID application.Performance data must be collected and analyzed for co-allocating resource efficiently,obtaining high performance and fault toleration.Furthermore,with the development of Internet and GRID,the exchange of data between virtual organiz-tions is becoming more and more important,and the type of performance is increasing following the increasing of the resource type,which requires a proper representation of the performance data.This paper does some research on the collection,analysis and representation of the performance data,and presents a Grid-oriented performance tool prototype:THGPT,which can achieve the runtime performance data,describe the data in XML,and implement a browserbased visualization tool of performance data analysis.  相似文献   

4.
D. B. Wortman  S. Zhou  S. Fink 《Software》1994,24(1):111-125
This paper describes the issues involved in sharing data among processes executing co-operatively in a heterogeneous computing environment. In a heterogeneous environment, the physical representation of a data object may need to be transformed when the object is moved from one type of processor to another. As a part of a larger project to build a heterogeneous distributed shared memory system we developed an automated tool for generating the conversion routines that are used to implement representation conversion for data objects. We developed a novel method for processing source programs that allowed us to extract detailed information about the physical representation of data objects without access to the source code of the compilers that were generating those representations. A performance comparison with the more general XDR heterogeneous data conversion package shows that the customized conversion routines that we generate are 4 to 8 times faster.  相似文献   

5.
A functional approach to redesign   总被引:6,自引:0,他引:6  
This paper describes a methodology to assist in the identification of possible conceptual design variants during redesign. The approach is based on functional reasoning and involves: (1) the structural and functional analysis of an existing design; (2) the production of abstract representations of functions and design entities using conceptual graphs; and (3) design interrogation based on a functional tree approach. The research reported in this paper also focuses on the definition and the representation of elementary mechanical functions. Extended Backus-Naur Form (EBNF) notations are used to structure in a computable form, the relevant information (or design knowledge) conceptualised in either the conceptual graphs or the functional trees. EBNF syntax is also used to formulate rules which aid the partial automation of the reasoning process. The EBNF notations can be mapped to any programming language. A diaphragm valve is used as a case study to demonstrate the approach.  相似文献   

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崔翔  李晓雯  陈一峯 《软件学报》2015,26(12):3104-3116
异构集群多层次异构存储的特点,决定了在其上进行计算时,数据需要进行更多维度的划分.现有集群程序设计语言缺乏对多维数组传输和转置的统一表示机制.介绍多维数组维度转置的表示方法和课题组实现的Parray语言,可以对异构集群复杂数据维度变换的数据操作进行清晰表示.同时介绍基于数组维度类型程序设计方法和Parray语言实现的天河1A系统上的大规模3维FFT,该算法代码实现简洁,同时得到了良好的性能和可延展性.  相似文献   

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A class of transformations of functional programs based on symbolic execution and simplification of conditionals is presented. The operational symbolic semantics of a family of functional languages is defined exploiting a set-theoretic notion of symbolic constants. An effective transformation able to simplify a functional program via removal of conditionals is discussed. Finally, it is shown that a structural approach, based on abstract data type specifications, provides a suitable representation for symbolic constants.  相似文献   

9.
Programming languages have traditionally had more data types than database systems. The flexibility of abstract types could make a database system more useful in supporting application development. Abstract types allow users to think about and manipulate data in terms and structures that they are familiar with. This paper proposes that databases have a type system interface and describes a representation of a type system in terms of relations. The type system model supports a variety of programming language constructs, such as user-defined parameterized data types and user-defined generic operations. The efficiency of the type system is compared to the access time of the database system.  相似文献   

10.
Owing to their inherent nature, terrorist activities could be highly diversified. The risk assessment becomes a crucial component as it helps us weigh pros and cons versus possible actions or some planning pursuits. The recognition of threats and their relevance/seriousness is an integral part of the overall process of classification, recognition, and assessing eventual actions undertaken in presence of acts of chem.-bio terrorism. In this study, we introduce an overall scheme of risk assessment realized on a basis of classification results produced for some experimental data capturing the history of previous threat cases. The structural relationships in these experimental data are first revealed with the help of information granulation – fuzzy clustering. We introduce two criteria using which information granules are evaluated, that is (a) representation capabilities which are concerned with the quality of representation of numeric data by abstract constructs such as information granules, and (b) interpretation aspects which are essential in the process of risk evaluation. In case of representation facet of information granules, we demonstrate how a reconstruction criterion quantifies their quality. Three ways in which interpretability is enhanced are studied. First, we show how to construct the information granules with extended cores (where the uncertainty associated with risk evaluation could be reduced) and shadowed sets, which provide a three-valued logic perspective of information granules given in the form of fuzzy sets. Subsequently, we show a way of interpreting fuzzy sets via an optimized set of its α-cuts.  相似文献   

11.
基于计算心象的美术图案构图知识表达   总被引:2,自引:0,他引:2  
诸葛源  潘云鹤 《软件学报》1997,8(10):738-744
美术图案构图知识表达是计算机辅助美术图案设计具有智能的基础.计算心象是根据认知科学的研究,对人脑心象的计算机模拟.本文根据计算心象的表示模型,提出了一个美术图案构图知识的深层表达、视觉表达和空间表达模型及其上的操作.它从表达子形状的视觉形状和空间关系出发,表达构图知识的形象信息与抽象信息.  相似文献   

12.
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   

13.
This paper describes a uniform approach to the automation of verification tasks associated with while statements, representation functions for abstract data types, generic program units, and abstract base classes. Program units are annotated with equations containing symbols defined by algebraic axioms. An operation's axioms are developed by using strategies that guarantee crucial properties such as convergence and sufficient completeness. Sets of axioms are developed by stepwise extensions that preserve these properties. Verifications are performed with the aid of a program that incorporates term rewriting, structural induction, and heuristics based on ideas used in the Boyer-Moore prover. The program provides valuable mechanical assistance: managing inductive arguments and providing hints for necessary lemmas, without which formal proofs would be impossible. The successes and limitations of our approaches are illustrated with examples from each domain  相似文献   

14.
The well-known term model constructions for equational abstract data type specifications provide a basis for elementary semantic reasoning, but their models lack the structure necessary for reasoning about relationships between the elements. Based upon the identities supplied in the data type's specification, we define a congruence relation which describes the relative ‘answer producing’ behaviour of words in the data type language, leading to a partially ordered qoutient algebra model. For those data types whose identity sets satisfy a condition implying the Church-Rosser (confluence) property, Wadsworth's approximation property holds: the meaning of a word in the model is the least upper bound of the meanings of its ‘syntactic approximants’. Thus the model provides fixed point properties while remaining fully abstract.  相似文献   

15.
This work investigates properties of a framework for mining relational data. The framework is constructed based on granular computing theory and is equipped with a method for deriving information granules from relational data. Such granules are the basis for discovering knowledge of a different type. It is shown in the paper that thanks to the properties one can improve the performance of tasks such as relational objects representation, search space limitation, and relational patterns generation.  相似文献   

16.
基因序列图形表达及聚类分析应用研究   总被引:2,自引:0,他引:2  
周迎春  骆嘉伟  杨莉 《计算机应用》2007,27(9):2330-2333
在基因序列图形表达模型研究的基础上,提出了一种新的非退化的基因图形三维表示方法。该表达方法不仅避免了图形的重叠和交叉,同时还保留了序列的生物学特征。利用该表达方法对H5N1病毒基因序列进行数字特征的提取并引入基于多维PFS判别函数进行模糊聚类分析应用。在聚类分析过程中直接利用数字特征矩阵作为分析数据,分析结果表明:利用文中所给图形表达建立基因序列数字特征矩阵进行的聚类分析具有一定的合理性。  相似文献   

17.
作为一种新的句子语义表示方法,抽象语义表示(AMR)将一个句子抽象为单根有向无环图,目前已经建立了较大规模的英文语料库。然而,句子中的词语和AMR图的概念对齐信息缺失,使得自动分析效果和语料标注质量受到影响,同时中文尚无较大规模的AMR语料库。该文介绍了中文AMR语料库的构建工作,针对汉语特点调整了AMR的标注体系,增加对复句关系的标注,提出了融合概念对齐的一体化标注方案,解决了中英文输入法频繁切换的问题,增加了错别字纠正和未标注词高亮功能,提高了标注效率。然后,从CTB中选取了6 923句进行人工标注,形成中文AMR语料库,统计得到图和环的比例分别为48%和1%,以及利用对齐信息才能获取的非投影句的比例32%,为中文AMR的理论和自动分析研究奠定基础。  相似文献   

18.
The Fortran Abstract Data (FAD) system was designed to facilitate the structured reuse of Fortran-callable software. FAD uses data abstraction to implement information hiding. It lets the implementer of a data type explicitly control how instances of that type are used, while itself utilizing Fortran's separate compilation and the vast collection of available Fortran libraries. The principle and methods of information hiding are discussed. The use of FAD, which is designed for situations where the user of an abstract data type is distinct from the implementer of the abstract data type, is described. Some related work is examined  相似文献   

19.
The vanishing line is useful information for recovering affine properties of the plane in computer vision. This paper describes how to determine analytically the vanishing line from a single perspective view of a plane containing the four points of known normalized barycentric coordinates in a general position, and further how to compute the vanishing line via the eigenvector representation. We also propose that the projectivity may be expressed directly and analytically from the vanishing line and three 3D–2D point correspondences. It is shown that plane affine properties may be computed and the metric may be recovered from known metric information, which includes an angle, two equal but unknown angles, and a length ratio of two non-parallel line segments, without using the image of the circular points as an intermediate step. The correctness and performance of the novel results are demonstrated by thorough testing on both synthetic and real data.  相似文献   

20.
Soccer is a competitive and collective sport in which teammates try to combine the execution of basic actions (cooperative behavior) to lead their team to more advantageous situations. The ability to recognize, extract and reproduce such behaviors can prove useful to improve the performance of a team in future matches. This work describes a methodology for achieving just that makes use of a plan definition language to abstract the representation of relevant behaviors in order to promote their reuse. Experiments were conducted based on a set of game log files generated by the Soccer Server simulator which supports the RoboCup 2D simulated robotic soccer league. The effectiveness of the proposed approach was verified by focusing primarily on the analysis of behaviors which started from set-pieces and led to the scoring of goals while the ball possession was kept. One of the results obtained showed that a significant part of the total goals scored was based on this type of behaviors, demonstrating the potential of conducting this analysis. Other results allowed us to assess the complexity of these behaviors and infer meaningful guidelines to consider when defining plans from scratch. Some possible extensions to this work include assessing which plans have the ability to maximize the creation of goal opportunities by countering the opponent’s team strategy and how the effectiveness of plans can be improved using optimization techniques.  相似文献   

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