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1.
Chen Qiming 《计算机科学技术学报》1988,3(2):113-130
In this paper a generalized object-oriented approach for complex object modeling is proposed,which ischaracterized by adding the concept of Meta-Class into the object-oriented paradigm for unifying thehandling of object types and primary data models,and also characterized by integrating the modeling ofobject type hierarchy and object configuration hierarchy.Concepts such as Compositional RelationshipObject,Face,Object Configuration Schema Expression,Object Skeleton are introduced to specify objectstructure,to support high degree of object sharing and to offer high degree of data independence.Operationson the class hierarchy,the object configuration structures and the object instances are developed respectivelywith distinguished semantics.This approach provides an extended object-oriented framewerk for handlingcomplex objects in any AI or database system(?). 相似文献
2.
词计算和语言动力学系统的基本问题和研究 总被引:9,自引:2,他引:7
语言动力学研究的实质是如何通过词计算在语言层次上动态地有效利用信息,解决复杂系统的建模、分析、控制和评估问题.语言动力学研究的主要思想是如何借助于一般数值动力学中行之有效的概念、框架、方法等,建立自己的相应体系.语言动力学将主要应用于数值动力学系统的抽象化分析,基于词描述的经济、社会、管理和生态系统的动态分析、决策综合、政策评估、以及大数据量的知识挖掘和动态表示等.这方面研究的最终目的是建立连接人类的语言知识表示与计算机的数字知识表示的桥梁,成为下一代智能化人机交互和知件体系的理论基础之一.本文简要讨论词计算和语言动力学系统的一些基本问题及研究. 相似文献
3.
Object models or class diagrams are widely used for capturing information system requirements in terms of classes with attributes and operations, and relationships among those classes. Although numerous guidelines are available for object modeling as part of requirements modeling, developing quality object models has always been considered a challenging task, especially for novice systems analysts in business environments. This paper presents an approach that can be used to support the development of quality object models. The approach is implemented as a knowledge-based system extension to an open source CASE tool to offer recommendations for improving the quality of object models. The knowledge component of this system incorporates an ontology of quality problems that is based on a conceptual model quality framework commonly found in object models, the findings of related empirical studies, and a set of analysis patterns. The results obtained from an empirical evaluation of the prototype demonstrate the utility of this system, especially with respect to recommendations related to the model completeness aspect of semantic quality. 相似文献
4.
基于Pi演算的跨组织工作流建模研究 总被引:1,自引:0,他引:1
传统的工作流建模方法主要用于描述组织内部流程,因而难以描述跨组织工作流面向流程、组合、抽象、涉及多个自治系统通信合作的新特点.针对此问题,提出了一种基于Pi演算的跨组织工作流建模方法,利用Pi演算的并发计算操作符,将跨组织业务流程建模为一组自治且并发执行的组织内子流程的组合,子流程建模为组织内本地流程定义和组织间控制约束的组合.基于Pi演算的弱互相似理论,验证了两个跨组织子流程外部行为的相等性,用于帮助组织内私有流程的外部抽象.基于该方法建立的跨组织工作流模型在子流程间建立了一种松耦合的关系,适用于动态的跨组织环境,同时基于严格的形式化方法,便于分析和验证. 相似文献
5.
Pach F.P. Feil B. Nemeth S. Arva P. Abonyi J. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2006,36(1):136-153
Process manufacturing is increasingly being driven by market forces, customer needs, and perceptions, resulting in more and more complex multiproduct manufacturing technologies. The increasing automation and tighter quality constraints related to these processes make the operator's job more and more difficult. This makes decision support systems (DSSs) for the operator more important than ever before. A traditional operator support system (OSS) focuses only on specific tasks that are performed. In the case of complex processes, the design of an integrated information system is extremely important. The proposed data-warehouse-based OSS makes possible linking complex and isolated production units based on the integration of the heterogenous information collected from the production units of a complex production process. The developed OSS is based on a data warehouse designed by following the proposed focus-on-process data-warehouse-design approach, which means stronger focus on the material and information flow through the entire enterprise. The resulting OSS follows the process through the organization instead of focusing separate tasks of the isolated process units. For human-computer interaction, front-end tools have been worked out, where exploratory data analysis and advanced multivariate statistical models are applied to extract the most informative features of the operation of the technology. The concept is illustrated by an industrial case study, where the OSS is designed for the monitoring and control of a high-density polyethylene (HDPE) plant. 相似文献
6.
In this paper, an effective particle swarm optimization (PSO) is proposed for polynomial models for time varying systems. The basic operations of the proposed PSO are similar to those of the classical PSO except that elements of particles represent arithmetic operations and variables of time-varying models. The performance of the proposed PSO is evaluated by polynomial modeling based on various sets of time-invariant and time-varying data. Results of polynomial modeling in time-varying systems show that the proposed PSO outperforms commonly used modeling methods which have been developed for solving dynamic optimization problems including genetic programming (GP) and dynamic GP. An analysis of the diversity of individuals of populations in the proposed PSO and GP reveals why the proposed PSO obtains better results than those obtained by GP. 相似文献
7.
D. B. Kaber N. Segall R. S. Green K. Entzian S. Junginger 《Cognition, Technology & Work》2006,8(4):253-252
Cognitive task analysis (CTA) approaches are currently needed in many domains to provide explicit guidance on redesigning existing systems. This study used goal-directed task analysis (GDTA) along with abstraction hierarchy (AH) modeling to characterize the knowledge structure of biopharmacologists in planning, executing and analyzing the results of high-throughput organic compound screening operations, as well as the lab automation and equipment used in these operations. It was hypothesized that combining the results of the GDTA and AH models would provide a better understanding of complex system operator needs and how they may be addressed by existing technologies, as well as facilitate identification of automation and system interface design limitations. We used comparisons of the GDTA and AH models along with taxonomies of usability heuristics and types of automation in order to formulate interface design and automation functionality recommendations for existing software applications used in biological screening experiments. The proposed methodology yielded useful recommendations for improving custom supervisory control applications that led to prototypes of interface redesigns. The approach was validated through an expert usability evaluation of the redesigns and was shown to be applicable to the life sciences domain. 相似文献
8.
Timed Communicating Object Z 总被引:1,自引:0,他引:1
Mahony B. Jin Song Dong 《IEEE transactions on pattern analysis and machine intelligence》2000,26(2):150-177
This paper describes a timed, multithreaded object modeling notation for specifying real-time, concurrent, and reactive systems. The notation Timed Communicating Object Z (TCOZ) builds on Object Z's strengths in modeling complex data and algorithms, and on Timed CSP's strengths in modeling process control and real-time interactions. TCOZ Is novel in that it includes timing primitives, properly separates process control and data/algorithm issues and supports the modeling of true multithreaded concurrency. TCOZ is particularly well-suited for specifying complex systems whose components have their own thread of control. The expressiveness of the notation is demonstrated by a case study in specifying a multilift system that operates in real-time 相似文献
9.
Embedded Open Source Software (OSS) systems have been gaining a lot of attention in the embedded system area. The successful experience of embedded OSSs include Android, BusyBox, TRON, etc. Also, OSS market will be expanded not only to mobile phone OSS areas but also to other embedded OSS areas in the future. However, the poor handling of quality problem and customer support prohibit the progress of embedded OSS. Also, it is difficult for developers to assess the reliability and portability of embedded OSS on a single‐board computer. A method of software reliability assessment based on flexible hazard rate modeling for the embedded OSS is proposed in this paper. Also, several numerical examples are shown by using actual data. Moreover, this paper compares the proposed model with the conventional hazard rate models by using the comparison criteria of goodness‐of‐fit. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
10.
We propose a framework based on a synchronous multi-clocked model of computation to support the inductive and compositional
construction of scalable behavioral models of embedded systems engineered with de facto standard design and programming languages. Behavioral modeling is seen under the paradigm of type inference. The aim of the
proposed type system is to capture the behavior of a system under design and to re-factor it by performing global optimizing
and architecture-sensitive transformations on it. It allows to modularly express a wide spectrum of static and dynamic behavioral
properties and automatically or manually scale the desired degree of abstraction of these properties for efficient verification.
The type system is presented using a generic and language-independent static single assignment intermediate representation. 相似文献
11.
Bernhard Zimolong Shimon Y. Nof Ray E. Eberts Gavriel Salvendy 《Behaviour & Information Technology》1987,6(1):15-36
The review is based on an analysis of current literature of expert systems and of system engineering models in dynamic process control. It starts with an analysis of the mental operations and cognitive requirements needed for supervisory control. Mental models are discussed as a function of situational requirements as well as of personal strategies. Systems engineering models and expert systems are briefly described and their function as decision support tools evaluated. Criteria are the overall functionality, similarity of knowledge bases and reasoning strategies of the human and the support system, adaptability to the operator's skill level and self-explanation of the support system in the interaction mode. As a result, system engineering models are only of limited value for knowledge-based process control. Expert systems seem to be very valuable tools for augmenting human decision making in process control, if the interaction problem can be solved. 相似文献
12.
13.
F. Zoccheddu E. Gobbetti M. Livesu N. Pietroni G. Cherchi 《Computer Graphics Forum》2023,42(5):e14899
We introduce HexBox, an intuitive modeling method and interactive tool for creating and editing hexahedral meshes. Hexbox brings the major and widely validated surface modeling paradigm of surface box modeling into the world of hex meshing. The main idea is to allow the user to box-model a volumetric mesh by primarily modifying its surface through a set of topological and geometric operations. We support, in particular, local and global subdivision, various instantiations of extrusion, removal, and cloning of elements, the creation of non-conformal or conformal grids, as well as shape modifications through vertex positioning, including manual editing, automatic smoothing, or, eventually, projection on an externally-provided target surface. At the core of the efficient implementation of the method is the coherent maintenance, at all steps, of two parallel data structures: a hexahedral mesh representing the topology and geometry of the currently modeled shape, and a directed acyclic graph that connects operation nodes to the affected mesh hexahedra. Operations are realized by exploiting recent advancements in grid-based meshing, such as mixing of 3-refinement, 2-refinement, and face-refinement, and using templated topological bridges to enforce on-the-fly mesh conformity across pairs of adjacent elements. A direct manipulation user interface lets users control all operations. The effectiveness of our tool, released as open source to the community, is demonstrated by modeling several complex shapes hard to realize with competing tools and techniques. 相似文献
14.
Armen Bagdasaryan 《Simulation Modelling Practice and Theory》2011,19(4):1061-1087
The method for dynamic model synthesis and discrete simulation of complex hierarchical control systems is presented. The method provides integration of large data sets, monitoring data and expert knowledge with the process of simulation and analysis of system state dynamics, thus providing an extensible and evolvable environment and reuse of knowledge and simulation models. The method is based on the hierarchical state diagrams technique and control scenarios methodology. The general structure of corresponding computer simulation system is also proposed. We also outline general principles of computer realization of our simulation approach, and schemes of model-based knowledge representation. The proposed method is based on the object-oriented paradigm and is especially powerful in information-intensive environments. 相似文献
15.
V-HairStudio: an interactive tool for hair design 总被引:4,自引:0,他引:4
Zhan Xu Xue Dong Yang 《Computer Graphics and Applications, IEEE》2001,21(3):36-43
Graphical models of natural objects have become increasingly complex and sophisticated. Although researchers have made significant progress in modeling complex objects in the last decade, representing human hair realistically continues to challenge us. It presents problems in all aspects of computer graphics technologies, such as shape modeling, manipulation, rendering, and dynamic simulation. The article introduces a hair-designing system. Based on the cluster hair model, this designing tool provides a rich set of functionality for interactive hairstyle design in two levels of abstraction. The system is more powerful, and at the same time, more convenient and efficient for hair styling and manipulation than previous modeling systems. We can divide existing hair models into two categories: explicit geometric models and volume-density models 相似文献
16.
《Computer Standards & Interfaces》2007,29(3):343-354
The Unified Modeling Language (UML) is being used as the de-facto standard in the software industry. With the adoption of UML 2.0, the new enhancements allow this version to describe many of the elements found in today's software technology as well as Model Driven Architecture and Service-Oriented Architecture. Although the Object Management Group (OMG) has released several UML Profiles to tailor the language to specific areas, relational database modeling is not fully addressed in these profiles. Many existing software applications involve complex application layer implemented in object-oriented programming languages and at the same time use relational database systems as the back-end data store. Modeling the whole system in a consistent manner will help developers and end users better understand the application. In this work we show how to model relational database operations using UML. Atomic database operations are modeled based on our framework and are used as building blocks to model more complex database operations. 相似文献
17.
A dynamic Petri net model for iterative and interactive distributed multimedia presentation 总被引:2,自引:0,他引:2
Object Composition Petri Nets, Priority Petri Nets, Dynamic OCPN, and Enhanced P-Nets have extended the original Petri Net to achieve the modeling of media synchronization and asynchronous user interactions during multimedia playback. The dynamic Petri Net (DPN) has been conceptualized to tackle existing problems in these two areas of modeling distributed multimedia systems. DPN features dynamic modeling elements which allows iteration and hence is able to reduce graph sizes of synchronous playback models while allowing greater details to be shown. DPN also introduces asynchronous event handling techniques that are powerful and effective. DPN was used in the design and modeling of a multimedia orchestration tool which is a typical representation of an application that works in a distributed multimedia system. 相似文献
18.
Stefano Caselli Constantinos Papaconstantinou Keith L. Doty Shamkant Navathe 《Journal of Intelligent Manufacturing》1992,3(1):11-30
This paper discusses the integration of structural, functional and control knowledge in manufacturing workcell modeling, simulation and design. After an overview of applications of semantic and object-oriented data models in the manufacturing domain, issues relating to the control synthesis for manufacturing workcells are presented. In particular, a data model encompassing functional and control features, along with application domain structural knowledge, is developed. This model assists in explicitly representing the control aspects of engineering design within an object-oriented database and supports a task-level, functionality-driven, manufacturing workcell design. Since manufacturing workcells consist of a number of elements interacting in a complex manner, workcell control design is one of the most difficult steps in the workcell design procedure. Message passage, commonly used in object-oriented databases, provides no explicit modeling of the database behavior. Hence, it can not serve as a tool for the design of system control. On the other hand, Petrinets (PN) have proven successful in describing complex interaction among active agents. This paper will explore the incorporation of Petri nets as a basis for describing application control knowledge within a structure-function-control data model. 相似文献
19.
The introduction of ICT in techno-socio-economic systems, such as Smart Grids, traffic management, food supply chains and others, transforms the role of simulation as a scientific method for studying these complex systems. The scientific focus and challenge in simulations move from understanding system complexity to actually prototyping online and distributed regulatory mechanisms for supporting system operations. Existing simulation tools are not designed to address the challenges of this new reality, however, simulation is all about capturing reality at an adequate level of detail. This paper fills this gap by introducing a Java-based distributed simulation framework for inter-connected and inter-dependent techno-socio-economic system: SFINA, the Simulation Framework for Intelligent Network Adaptations. Three layers outline the design approach of SFINA: (i) integration of domain knowledge and dynamics that govern various techno-socio-economic systems, (ii) system modeling with dynamic flow networks represented by temporal directed weighted graphs and (iii) simulation of generic regulation models, policies and mechanisms applicable in several domains. SFINA aims at minimizing the fragmentation and discrepancies between different simulation communities by allowing the interoperability of SFINA with several other existing domain backends. The coupling of three such backends with SFINA is illustrated in the domain of Smart Grids and disaster mitigation. It is shown that the same model of cascading failures in Smart Grids is developed once and evaluated with both MATPOWER and InterPSS backends without changing a single line of application code. Similarly, application code developed in SFINA is reused for the evaluation of mitigation strategies in a backend that simulates the flows of a disaster spread. Results provide a proof-of-concept for the high modularity and reconfigurability of SFINA and puts the foundations of a new generation of simulation tools that prototype and validate online decentralized regulation in techno-socio-economic systems. 相似文献
20.
Object-based directional query processing in spatial databases 总被引:4,自引:0,他引:4
Xuan Liu Shekhar S. Chawla S. 《Knowledge and Data Engineering, IEEE Transactions on》2003,15(2):295-304
Direction-based spatial relationships are critical in many domains, including geographic information systems (GIS) and image interpretation. They are also frequently used as selection conditions in spatial queries. In this paper, we explore the processing of object-based direction queries and propose a new open shape-based strategy (OSS). OSS models the direction region as an open shape and converts the processing of the direction predicates into the processing of topological operations between open shapes and closed geometry objects. The proposed strategy OSS makes it unnecessary to know the boundary of the embedding world and also eliminates the computation related to the world boundary. OSS reduces both I/O and CPU costs by greatly improving the filtering effectiveness. Our experimental evaluation shows that OSS consistently outperforms classical range query strategies (RQS) while the degree of performance improvement varies by several parameters. Experimental results also demonstrate that OSS is more scalable than RQS for large data sets. 相似文献