基于信息进化的并行设计研究

提出了在并行设计中信息进化的观点,以信息 进化矩阵为基础,导出了设计过程中的各活动信息调整量模型,研究了并行设计过程中耦合 活动集从迭代到收敛的规律,为并行设计的规划和控制提供了理论依据．     

基于信息化的并行设计研究

提出了在并行设计中信息进化的观点,以信息进化矩阵为基础,导出了设计过程中的各活动信息调整量模型,研究了并行设计过程中耦合活动集从迭代到收敛的规律,为并行设计的规划和控制提供了理论依据．     

Topology based 2D engineering drawing and 3D model matching for process plant

Process plant models mainly include 3D models and 2D engineering drawings. Matching calculation between these CAD models has wide applicability in model consistency check and retrieval. In process plant, engineering design standards make 2D engineering drawing and 3D model differ in geometry, proportion and structure, leading to the inapplicability of current shape-feature based matching approaches. Since connection relationships between components are the core of a process plant, a topology based algorithm is proposed. Firstly, by exploiting components as vertices and relationships as edges, both 2D engineering drawing and 3D model are preprocessed into graph structures. Then each model’s relationship types are extracted from the graph. Finally, regarding the extracted relationship types as primary feature, feature similarity is calculated to measure the matching degree between their corresponding models. The proposed algorithm is geometric deformation invariant. Experiments with industrial applications are presented, which demonstrates the effectiveness and feasibility of the proposed algorithm.     

空间数据库主动规则并发行为控制研究

网络环境下空间信息大规模应用中常常有大量的用户规则同时触发，这带来了规则并发行为的控制和效率问题．目前大多数方法难以满足大量用户同时操作时的频繁动态更新，因此提出标注事件图分析模型及并发规则集终止性分析算法，通过实例说明算法的有效性和通用性．在并发索引结构Rlink树基础上，提出一种支持空间数据库主动规则频繁更新的混合索引结构HRlink树及改进的自底向上更新算法IBUU．实验仿真表明，采用IBUU算法的HRlink树频繁更新性能大大高于Rlink树．     

带复杂数据结构的模型检测工具

模型检测是近二十几年来最成功的自动验证技术之一，而模型检测工具的开发是将模型检测和实际相结合的关键．为了有效地对涉及到复杂数据类型的并发传值系统进行模型检测，总结了以扩展的带赋值符号迁移图和模态图分别作为并发系统和逻辑公式的语义模型来实现模型检测工具的工作，特别是将复杂数据结构引入传值进程定义语言和带赋值符号迁移图．同时结合实际例子说明模型检测工具的有效性．     

自动信任协商中环策略依赖检测技术

针对自动信任协商(ATN)可能出现协商过程无限循环的问题,对循环产生的原因进行了分析并设计相应的检测算法以及时发现并终止协商循环。协商双方策略间的依赖关系存在环是无限循环协商产生的原因,将策略间的依赖关系建模成简单图并证明了模型的正确性;分析简单图的可达矩阵计算过程并给出简单图环检测定理,基于该定理设计检测算法对环策略依赖进行检测。最后,通过实例验证了算法的可行性。     

Supporting communication and cooperation in distributed representation for adaptive design

Different types of graphs has been successfully used to represent designs at different stages of the design process. Changes to a model representing a design during the process can be modelled by applying graph transformations. In many real life design tasks the changes/updates can be carried out simultaneously on different parts of the design. Hence a model based on graph transformations is coupled with a multiagent paradigm to enable the parallelisation of these transformations to mimic the real life approach. In this paper a hypergraph representation and transformation model is used as a basis for building a multiagent system supporting distribution and adaptation in computer aided design. This representation can be applicable throughout the lifecycle of the design. It is based on research in formal language theory, like graph grammars, and distributed models including multiagent systems. The motivation for the work presented here is given and possible applications are described. The application of the theoretical results in a graph distribution toolkit proposed as a multiagent framework is also considered. To assure the efficiency of the system it should be implemented as a parallel multiagent system. The hypergraph distribution and partial replication, allowing for its parts to be managed by agents, is also presented. The approach is illustrated by a case study from the domain of building design, where it is used to represent, modify and maintain building information.     

A high-performance approach on mechanism isomorphism identification based on an adaptive hybrid genetic algorithm for digital intelligent manufacturing

The graph theory is an important method to achieve conceptual design for mechanism. During the process of kinematic structures enumeration using graph theory, isomorphism identification of graphs is an NP complete problem. It is important to improve the isomorphism identification efficiency and reliability. To solve the problem, an adaptive hybrid genetic algorithm is presented by mixing the improved genetic algorithm and local search algorithm. The crossover rate and mutation rate can be designed as adaptive parameters. Hence, the crossover rate and mutation rate can sustain the variety of the population and adjust the evolution. In the meantime, the pseudo-crossover operator is introduced to improve the search efficiency. In the last, some examples are illustrated to show the high efficiency of the algorithm by comparing with the results in other literatures.     

A reverse engineering process for design level document production from ADA code

The paper describes a reverse engineering process for producing design level documents by static analysis of ADA code. The produced documents, which we call concurrent data flow diagrams, describe the task structure of a software system and the data flow between tasks. Firstly, concurrent data flow diagrams are defined and discussed and then the main characteristics and features of the reconstruction process are illustrated. The process has been used to support maintenance and reuse activities on existing real-time software and to check consistency between design and code.     

Modeling and performance analysis of product development process network

Product development process (PDP) is a complex system, in which design activities and design resources are connected to each other according to specific rules. Considering the elements of PDP (complex forms of design activities, interdisciplinary collaboration and multiform resources) and relationships between them, a product development process network (PDPN) is proposed and its performance is further analyzed and optimized. In order to establish the PDPN, design activities and resources used in the PDP are mapped into the nodes of the network. And the relationships among the nodes are mapped into the edges. Then, a level-based evaluation model is proposed to illustrate the forming procedure of establishing the PDPN. Then, some typical topological and physical characteristics of the PDPN are defined and analyzed based on the complex network theory. In order to balance the resource load, the PDPN is divided into different communities, wherein a Girvan–Newman (GN) algorithm together with improved measure criterion is applied. Finally, the design process of a steam turbine rotor is chosen as an example to illustrate the feasibility and availability of the proposed method.