基于图元对象的工程产品CAD信息集成模型

产品信息建模是工程设计中各类产品信息通信，交换和共享的关键，工程产品信息模型要求具备统一，完备及动态的协同特征，文中针对工程设计的特点和工程产品的信息结构层次，通过“图元对象”概念的引入，图元对象粒度的建立和协同链接集成，在图元对象的内部关联和外部链接两个层次建立了工程产品CAD信息集成模型，最后在工程实现说明了该信息模型的合理性与有效性。     

基于任务元的工程产品CAD信息对象集成模型

工程设计是工程技术人员根据约束条件及有关规范,利用自身经验、专业知识及一系列分析、综合、评价得到满足特定要求的设计结果所进行的一种智能活动。它是一个十分复杂的过程,一般要经历方案设计、初步设计和施工图设计三个阶段,包括设计构思、结构计算、设计细化、施工图绘制、工程概预算等。这些活动需要各类产品信息的通讯、交换和共享,因此研究协同产品信息模型十分必要。本文针对工程设计的特点,提出并建立了工程产品CAD信息对象集成模型。最后     

覆盖件产品CEG集成知识模型及表达

产品集成知识模型是对几何模型，特征模型及其相应建模技术进一步的综合和扩展，是实现产品生命周期内信息综合表达的关键，在分析覆盖件产品对象类层次的基础上，提出了几何特征，规则对象和约束方法的面向对象表达策略，建立了集成构形、工程和几何知识描述的覆盖件产品模型，利用基于STEP标准的EXPRESS语言和KBE开发语言，通过语言联编实现产品特征信息和工艺设计知识的高度集成来支持智能化工艺设计过程。     

一种计算机支持的飞机协同设计中的感知模型

为了实现飞机设计中的协同感知,针对其学科多、设计流程复杂的特点,通过研究飞机协同设计中涉及的感知信息及其关联、层次,以协同对象附加设计资源分配、产品结构、工作流、设计意图等工程背景信息的方式建立了一种感知模型.该模型使用设计资源空间呈现不同学科在同一物理量上的冲突;针对不同深度的感知需求设计呈现模式,并据此给出实现协同...     

基于STEP标准的产品功能信息建模

分析了集成信息CAD系统中要解决的产品模型信息描述问题。基于STEP标准和IDEF产品建模方法,提出了基于功能层的产品信息建模和产品信息模型的三层结构：功能层、零部件层和构造层。以工程中业已标准化的滚动轴承为对象建立了基于STEP标准的产品功能信息EXPRESS描述模型,为集成信息CAD系统的信息集成中性环境的建立提供了基础。     

基CORBA/Web技术的企业级信息系统集成

以制造企业产品远程协同设计制造为背景,基于分布式对象CORBA集成平台,在分布式异构网络环境下,研究基于Web的企业信息系统分布式应用互操作层次体系结构、异构信息数据资源及应用系统与Internet/In-tranet的无缝接入方法。针对异地信息资源的远程访问与应用互操作的实现模型、实现方法与支撑机制进行论述,提出了企业级信息系统集成的分布式应用互操作体系结构模型与实现模型。     

基于CORBA／Web技术的企业级信息系统集成

以制造企业产品远程协同设计制造为背景，基于分布式对象CORBA集成平台，在分布式异构网络环境下，研究基于Web的企业信息系统分布式应用互操作层次体系结构、异构信息数据资源及应用系统与Internet／Intranet的无缝接入方法。针对异地信息资源的远程访问与应用互操作的实现模型、实现方法与支撑机制进行论述，提出了企业级信息系统集成的分布式应用互操作体系结构模型与实现模型。     

基于STEP的RMS信息模型研究及实现

为了满足产品数字化协同研制模式对可靠性、维修性、保障性（RMS）数据共享和交换的要求，针对RMS工程的“全特性”、“全阶段”和“全系统”的特点，建立了基于产品模型数据交换标准（STEP）的RMS信息模型，并研究提出了该模型在产品数据管理系统（PDM）下的实现方法，最后给出了RMS模型及其实现方法在企业信息集成中的应用模式及案例验证。     

基于STEP方法学的模具产品集成信息建模技术研究

以冲压模具为研究对象,基于ＳＴＥＰ标准方法学,提出了三层结构式的模具产品模型,建立了模具产品集成信息模型ＤＰＩＩＭ。充分考虑模具产品生命周期的特点,将模具产品集成信息模型ＤＰＩＩＭ进一步分为需求信息模型、活动信息模型、产品信息模型及制造信息模型,并探讨了模具产品集成信息模型ＤＰＩＩＭ中集成资源的内容,然后定义了７个基本实体库,以作为具体描述模具产品集成信息模型ＤＰＩＩＭ的基本工具。最后,按照ＳＴＥ     

基于工作流管理的智能CAD集成系统

介绍了工作流管理的现状和产品数据管理技术，比较了知识处理与数据处理的特点，提出了一种以工作充为核心的智能PDM系统集成解决方案，通过在PDM系统中集成人工智能，使用STEP标准建立信息模型和数据交换，增强系统在信息和应用集成的过程中的适应性和开放性，提供基于Internet/Intranet的共享零件库和标准工程手册数据库，将工程设计和管理人员解放出来，可提高产品设计和资源利用率。     

Phenomenologial foundations of conceptual product modelling in architecture,engineering and construction

The ultimate goal of conceptual modelling in architecture, engineering and construction (AEC) has been to define the data structures that could be used to describe the entire built environment through all its life cycle stages — from inception and design to demolition. In spite of the magnitude and complexity of this task, the theoretical foundations of modelling received little attention. In this paper, the theoretical foundations of the traditional modelling approaches are questioned using phenomenology and hermeneutics as philosophical base. The author exposes the difference between the remodelling of some existing models, the modelling of physical objects and the modelling of psychical, intentional objects. The author concludes that AEC or building product and process models do not model objective reality but the modeller's partial understanding of that reality. Therefore, several correct but different models may and should exist. Future software architectures in AEC should not be built on a unified, centralized model but, on a combination of models, which may not be standardised but whose schemas are encoded in a standard manner.     

Distributed AEC databases for collaborative design

The Architecture, Engineering and Construction (AEC) design process for a facility involves participation of many design specialists. These participants are architects, engineers (structural, mechanical and electrical) and contractors, who may be independent design professionals or design teams within an organization. From the viewpoint of information processing, two characteristic features distinguish the AEC design process from many other design domains. Firstly, there is a massive volume of design data involved in the design of each of its component specialties. Secondly, the specialization of the disciplines themselves warrant substantial autonomy. For design automation, this autonomy should be realized without sacrificing the collaborative nature of the multidisciplinary AEC design process. We propose autonomous AEC databases to deal with the first issue, and a global constraint maintenance mechanism for the second. Autonomous design databases can support the existing local applications in architectural, structural and mechanical engineering, and construction domains. However, a set of inter-disciplinary constraints needs to be enforced to ensure spatial and functional consistency of the design. A global constraint checking mechanism frees designers from the burden of keeping track of various design changes that may result in cross-functional conflicts. In this paper, we discuss the relevant issues for constraint management on distributed AEC databases. Although specific AEC examples will be used, the presentation is general enough to be applicable to other design domains, such as VLSI and manufacturing.     

Development of alternative reality environments for spacecraft habitat design evaluation

Virtual Reality - Alternative reality (XR) tools are becoming more commonplace in the realm of architecture, engineering, and construction (AEC); however, these digitally immersive technologies...     

3D visualization for building information models based upon IFC and WebGL integration

Multimedia Tools and Applications - Building Information Modeling (BIM) technology provides broad-ranging support of AEC (architecture, engineering, and construction) industry needs. The inclusion...     

一款高精度数控振荡器设计与实现

数控振荡器是全数字锁相环的关键部件,为其提供高频输出时钟。数控振荡器的性能直接影响全数字锁相环的频率范围和抖动性能。提出了一种基于全数字标准单元库设计的数控振荡器,该结构采用粗调、中调和精调级联的调节机制,实现了0.5GHz~2.6GHz的高频率范围和0.8 ps的高调节精度。在先进工艺下实现了该数控振荡器设计,并基于此数控振荡器完成了全数字锁相环的系统设计,系统抖动小于2 ps,功耗10 mW。     

Conversational artificial intelligence in the AEC industry: A review of present status,challenges and opportunities

The idea of developing a system that can converse and understand human languages has been around since the 1200 s. With the advancement in artificial intelligence (AI), Conversational AI came of age in 2010 with the launch of Apple’s Siri. Conversational AI systems leveraged Natural Language Processing (NLP) to understand and converse with humans via speech and text. These systems have been deployed in sectors such as aviation, tourism, and healthcare. However, the application of Conversational AI in the architecture engineering and construction (AEC) industry is lagging, and little is known about the state of research on Conversational AI. Thus, this study presents a systematic review of Conversational AI in the AEC industry to provide insights into the current development and conducted a Focus Group Discussion to highlight challenges and validate areas of opportunities. The findings reveal that Conversational AI applications hold immense benefits for the AEC industry, but it is currently underexplored. The major challenges for the under exploration were highlighted and discusses for intervention. Lastly, opportunities and future research directions of Conversational AI are projected and validated which would improve the productivity and efficiency of the industry. This study presents the status quo of a fast-emerging research area and serves as the first attempt in the AEC field. Its findings would provide insights into the new field which be of benefit to researchers and stakeholders in the AEC industry.     

Implementing information systems with project teams using ethnographic-action research

Architecture, engineering, and construction (AEC) projects are characterized by a large variation in requirements and work routines. Therefore, it is difficult to develop and implement information systems to support projects. To address these challenges, this paper presents a project-centric research and development methodology that combines ethnographic observation of practitioners working in local project organizations to understand their local requirements and the iterative improvement of information systems directly on projects in small action research implementation cycles. The paper shows the practical feasibility of the theoretical methodology using cases from AEC projects in North America and Europe. The cases provide evidence that ethnographic-action research is well suited to support the development and implementation of information systems. In particular, the paper shows that the method enabled researchers on the cases to identify specific problems on AEC projects and, additionally, helped these researchers to adapt information systems accordingly in close collaboration with the practitioners working on these projects.     

基于图形理解的预算工程量提取算法

分析了建筑图样（施工图）视图表达和图形理解的特点，基于工程量相关图形信息中各类图形实体的信息理解关系，提出了关联、特征实体的概念；给出施工图中工程量相关信息图形理解策略，并将图形理解的方法应用于预算工程的自动提取，为实现建筑CAD与概预算一体化提供新的途径；以土石方工程量为例，给出了工程量相关信息理解、搜索和识别算法。