Knowledge-Based System Development Tools for Processing Design Specifications

Code-compliance checking in any engineering design process is typically a nonsequential activity that requires extensive data managmenkt and decision making. Knowledge-based system methodology can be applied to solve some of the problems in processing code specifications that could not be addressed by traditional procedural programming languages. Many software development tools are currently available to assist in the development of knowledgte-based systems for specific applications. The characteristics of each tool vary with the knowledge representation and inference methodologies, and differ with the user interface and other features for development. An evaluation of seven knowledge-based system development tools is presented in this paper. The suitability of each development enviornment for design assistance by processing code specifications is investigated by means of prototype design applications. A brief descrioption of the features of each development too, implementation details of prototype applications, and a qualitative comparison of the tools on the basis of suitability to process design code spacifications are presented.     

BIM-based automated design and planning for boarding of light-frame residential buildings

Building information modelling technology provides a game-changing solution to address the challenges encountered in the AEC industry. However, this technology currently is not sufficient to fulfil the needs of construction practitioners in terms of proactive design and planning for boarding of light-frame residential buildings. This is partially due to the fact that boarding design and planning requires trades' know-how and substantial manual effort in developing the building information models. Current manual and ad hoc decision making for boarding of light-frame buildings leads to the generation of a significant amount of material waste. This research thus proposes a rule-based automated building information model (BIM) approach for designing boarding layout and planning material sheet cutting, resulting in practically feasible solutions with minimal material waste. In this research, object-based computer-processable layout design rules are comprehensively formalised based on trades' know-how. On this basis, rule-based design algorithms are further developed and integrated with mathematical algorithms in order to automatically generate design and planning alternatives while minimising material waste. Rich information in the BIM is leveraged to automate the rule-based boarding design and planning. A prototype system is developed based on Autodesk Revit via Application Programming Interface. A typical wood-framed residential building is used as a case study to test the developed prototype system. The results show the proposed approach successfully preserves the know-how of senior trades people while also minimising material waste in automating the boarding design and planning.     

Automated tower crane planning: leveraging 4-dimensional BIM and rule-based checking

Reviewing tower crane plans in the pre-construction phase is an iterative process and one that is in need of an approach that improves its effectiveness and efficiency. This study proposes a framework that integrates 4D modeling and rule-based checking for reviewing tower crane plans. A template of crane-specific rules that are based on prevailing tower crane design standards in the United States was developed. This framework is capable of automating the review process and identifying potential spatial and capacity conflicts based on design models and construction schedules. This work presents a prototype system to which crane-specific rules are applied in a rule-checking platform that uses a 4D model as input. In the validation tests, the system's effectiveness is demonstrated by its high recall rates. Efficiency is achieved through diminishing manual interventions. The proposed approach also gives rise to an automated tower crane-planning process, reducing the need for manual input. Higher efficiency allows users to review more alternatives consistently when compared with the manual approach.     

An ontology-based approach for formalisation and semantic organisation of conformance requirements in construction

This paper presents an ontology-based method for the formalisation and application of construction conformance requirements for effective code checking. This research continues our work on the development of a generic model automating the conformance checking of construction projects against building codes. We start from the analysis of the related research on the formalisation and organisation of building codes that allows us to formulate our approach for semantic annotation and scheduling of conformance requirements for conformance checking task. Our approach comprises 5 main steps: formalisation, semantic annotation, classification, context-based scheduling and semantic search of conformance requirements. They are implemented as corresponding key components of the C3R (Conformance Checking in Construction — Reasoning) prototype that we have developed to model the conformance checking process in construction. Finally, we discuss the ongoing work and perspectives of our research: the validation of our model by construction practices and the enrichment of our approach by usage-based knowledge.     

An object-oriented framework for dynamic ecosystem modeling: application for integrated risk assessment.

Ecological risk assessment requires the integration of a wide range of data on anthropogenic processes, ecological processes and on processes related to environmental fate and transport. It is a major challenge to assemble a simulation system that can successfully capture the dynamics of complex ecological systems and an even more serious challenge to be able to adapt such a simulation to shifting and expanding analytical requirements and contexts. The dynamic information architecture system (DIAS) is a flexible, extensible, object-based framework for developing and maintaining complex simulations. DIAS supports simulations in which the real-world entities that make up ecological systems are represented as software 'entity objects'. The object-oriented integrated dynamic landscape analysis and modeling system (OO-IDLAMS) provides a good example of how DIAS has been used to build a suite of models for the purpose of assessing the ecological impacts of military land use and land management practices. OO-IDLAMS is a prototype conservation modeling suite that provides military environmental managers and decision-makers with a strategic, integrated and adaptive approach to natural resources planning and ecosystem management. The OO-IDLAMS prototype used Fort Riley, Kansas as a case study to demonstrate DIAS' capabilities to offer flexibility, interprocess dynamics and cost-effective reuse of code for ecosystem modeling and simulation. DIAS can also readily lend itself to other applications in ecological risk assessment. It has great potential for the integration of ecological models (associated with biological uptake and effects) with environmental fate and transport models. A DIAS ecological risk assessment application could be used to predict the magnitude and extent of ecological risks and evaluate remedy effectiveness in a timely and cost-effective manner.     

Co-simulation of innovative integrated HVAC systems in buildings

Integrated performance simulation of buildings' heating, ventilation and air-conditioning (HVAC) systems can help in reducing energy consumption and increasing occupant comfort. However, no single building performance simulation (BPS) tool offers sufficient capabilities and flexibilities to analyse integrated building systems and to enable rapid prototyping of innovative building and system technologies. One way to alleviate this problem is to use co-simulation, as an integrated approach to simulation.

This article elaborates on issues important for co-simulation realization and discusses multiple possibilities to justify the particular approach implemented in the here described co-simulation prototype. The prototype is validated with the results obtained from the traditional simulation approach. It is further used in a proof-of-concept case study to demonstrate the applicability of the method and to highlight its benefits. Stability and accuracy of different coupling strategies are analysed to give a guideline for the required coupling time step.     

NoDes: kNOwledge-based modeling for detailed DESign process — from analysis to implementation

This paper reviews the nature of detailed design process and discusses the implementation of a knowledge-based system (KBS) founded on a protocol analysis study. The main objective is to discuss the features of a knowledge-based modeling approach, kNOwledge-based modeling for detailed DESign process (NoDes). This approach was first used for the development of the wind, which is an interactive KBS for the synthesis of window parts. We take the wind as an exemplary prototype implementation to demonstrate the abilities and performance of our knowledge-based modeling approach. Besides knowledge analysis and simulation of task execution, this paper also argues the efficiency of the object-oriented programming approach in the system implementation.     

Validations for ensuring the interoperability of data exchange of a building information model

During the design and construction phases of building projects, domain experts iteratively exchange building information models. One of their goals is to ensure that the requirements and objectives of a proposed project are satisfied. In addition, most building information modeling software currently implements heterogeneous mapping processes in their IFC interfaces that bind their native models to the IFC format. However, such exchanges frequently do not realize intended geometric transformations, project requirements, and required syntactic and semantic conditions in building model data, exacerbating the problem of model integrity and resulting in expensive changes during the construction and operation phases. These problematic issues have been addressed by the development of solid frameworks for validating a building design. This paper surveys six currently available applications for validating building design data and identifies their strengths and weaknesses: The Express Engine's EXPRESSO, the JDSAI™, the EXPRESS Data Manager™, the IFC server ActiveX Component, the IfcDoc, and the Solibri Model Checker^®. We also structured the validation processes into three types of tasks: 1) a syntax check of the assurance of compliance with the IFC schema defined by the EXPRESS language, 2) semantic and syntactic assessment in terms of conformity to model view definitions, which consist of concept modularizations, and 3) the validation of design programming requirements that evaluates regulations, project criteria, owner requirements, and functional performance. The purpose of this survey, based on available software that supports the validation of building model data for these three types of interoperability issues, is to integrate diverse checking approaches, as a basis for improving what are now widely distributed efforts.     

An interface system for computerized energy analyses for building designers

This paper describes research on a computer model for building energy simulation. The main goal of this effort has been to provide building designers a better design tool for energy optimization in their building design processes. With the rapid development in computing technology, today's expectation for computer-aided building design (CABD) systems have matured to an advanced level—to the point where designers are open to the idea of computers helping them in the thought process and not just being used to manipulate and represent geometric shapes [J. Pohl et al., 1992. A Computer-Based Design Environment—Implemented and Planned Extensions of the ICADS Model. Design Institute Research Report, CADRU-06-92, California Polytechnic State University, San Luis Obispo, CA.]; [J.A. Clarke, A.D. Irving, 1988. Building Energy Simulation: An Introduction, Energy and Buildings, 10 (1988), Elsevier, pp. 157–159.]. By its very nature, design is a multidisciplinary and creative activity which encompasses all the relevant areas to be considered during the design process. Thus, the CABD system of today is expected to be a general purpose integrated system, rather than a domain-dependent isolated graphics system [J. Pohl, L. Myers, A. Chapman, J. Cotton, 1989. ICADS: Working Model Version 1, Design Institute Research Report, CADRU-03-89, California Polytechnic State University, San Luis Obispo, CA.]. This research effort embodies a prototype interface system for a building energy simulation model (ENERife). This interface system is not a simple layer between user and simulation model, but rather, a general interface strategy to control simulation models and relevant databases to be integrated into CABD. The system includes a user interface module, system interface module, general database handling module, automated input processor, building matrix system, and a result analysis and recovery system.     

Virtual components consisting of form,function and behavior

Software can produce a product model of a building as a consequence of the designers' actions in drawing and evaluating the design. The actions of the designer include interpreting, predicting and assessing the emerging design and describe the building in terms of forms, functions and behaviors. A software prototype has been implemented that incorporates this understanding of the design process in the field of building design. It employs object-oriented classes to represent forms, functions and behaviors. As a software user draws and interprets the design for multiple evaluation issues, the software creates a unique `virtual component' for each entity. During automated reasoning to evaluate the emerging design, virtual components collect and organize form, function and behavior instances to describe the parts of the building. In comparison to other product models, our approach, which we refer to as a `Virtual Product Model', better accommodates change, provides increased support for the design process and enriches the product representation by including function and behavior.     

An integrated construction planning system using object-oriented product and process modelling

An interactive planning system approach poses challenges to the efficient integration of the design and construction planning process. Current research is focused on organizational knowledge processing in building design and construction, such as the representation of object-oriented planning models and constraint management incorporating design, engineering and construction planning through several planning stages. Since building construction involves cooperation among designers, engineers and project managers, comprehensive organizational planning and management tools are relevant. The integrated construction planning system (ICPS) aims to cover a wide range of knowledge processing based on formalization and representation of building and construction systems. To realize the integrated construction planning system, appropriate modelling techniques need to be introduced. This paper presents the results of research on several issues such as formalization and representation of interactive design and construction planning processes, methods for incorporating project information, knowledge and constraints and the concept of applying an object-oriented paradigm to interactive building and construction system planning. A prototype system is also presented which integrates building space planning, building system planning, construction system planning, construction activity planning and construction site layout planning.     

Implementation of IFC-based web server for collaborative building design between architects and structural engineers

This paper presents the implementation of an Industry Foundation Class-based (IFC-based) information server for web-enabled collaborative building design between the architect and structural engineer. In this research, the Java 2 Platform, Enterprise Edition (J2EE) standard is employed to build the framework of a design information server; the web and XML technologies are used to implement the collaboration and information sharing mechanisms in the server. The Industry Foundation Classes (IFCs) are adopted as the information model of the server to facilitate the interoperability among multidisciplinary AEC software applications. The current implementation of the server system supports the automatic transformation of the design model contents and representations from the architectural domain to the structural domain, and remote visualization and interaction by Java applet and the Java3D technology. An algorithm that is able to deduce the topological relationship among different structural elements has been proposed in this paper. A case study is presented at the end of the paper to illustrate the use of the information server for the architectural and structural design collaboration.     

Asynchronous online collaboration in BIM generation using hybrid client-server and P2P network

This paper proposes a system to enable Internet-based modeling collaboration among teams from multiple disciplines for the development of a Building Information Model (BIM). The proposed networked system allows geographically separated design teams to work simultaneously on a single multi-disciplinary BIM, using a distributed system to achieve design integration and conflict resolution. An online collaborative modeling platform for inter-disciplinary collaboration was developed in this study. By using the proposed platform, members of various design teams can work in the same virtual modeling space, monitor the progress of other teams' work, and cooperate in real-time via the Internet. All design data is maintained in a central database providing secure and systematic data management. A hybrid client–server and peer-to-peer (P2P) network was proposed to enable such modeling collaboration. The network has two levels: specialized teams are connected through a client–server network; and the members of each team are connected through a P2P network. A BIM generation workflow with various support functions was proposed based on this hybrid network. A prototype system was developed to demonstrate the feasibility of the proposed collaboration model. Appropriate operating mechanisms are imposed to maintain the integrity of the system. Validation through a case study shows that the proposed collaboration model and system can reduce modeling time and improve modeling efficiency when compared to common modeling workflow.     

装配整体式预应力夹层板楼盖结构设计方法

介绍了装配整体式预应力混凝土夹层板在主跨度方向的承载力计算方法和正常使用极限状态的验算内容。详细描述了计算原理和叠合层与夹层板连接的构造措施。实例设计表明,预应力夹层板楼盖结构两个方向的设计均可采用现行规范中叠合式受弯构件的设计方法。     

风荷载作用下建筑钢结构人体舒适度限值探讨

在钢结构设计中,由于振动而引起的人体舒适度问题不可忽视。国内对钢结构适用性验算主要侧重于验算结构在风荷载作用下的水平侧移是否满足建筑设计标准限值的要求,对结构的人体舒适度问题关注较少。GB 50017—2003《钢结构设计规范》中对钢结构在风荷载作用下的人体舒适度限值也缺乏相关规定。针对此现状,首先对国内外有关人体舒适度的研究成果进行总结,介绍影响人体舒适度的因素,回顾和比较各国和各地区钢结构设计规范中有关人体舒适度的条文内容,探讨目前建筑钢结构人体舒适度限值研究中存在的一些问题,最后给出建筑钢结构在风荷载作用下建议采用的舒适度限值,为《钢结构设计规范》修订和工程应用提供参考。     

子结构拟动力试验方法在老旧住宅外套式加固改造工程中的应用

以北京前三门地区加固改造项目为工程背景，对子结构拟动力试验方法进行应用研究。介绍了用于拟动力试验的数值积分法（OS算法）及其在拟动力试验中的实现,开发了基于MTS电液伺服加载系统的结构拟动力试验软件TOHTP,针对采用外套式加固后的老旧住宅的1/2缩尺模型进行了子结构拟动力试验研究。研究结果表明： OS算法是对于大多数结构为无条件稳定的数值积分算法，适用于子结构拟动力试验；拟动力试验软件TOHTP正确实现了OS算法，对于建筑结构的拟动力试验方便有效；拟动力试验结果验证了加固后的老旧住宅能够满足现行规范的抗震性能要求。     

Intelligent building technologies: a case of Japanese buildings

Recent developments in building technologies in the USA, Europe and Japan reflect the trend towards more intelligent and energy-efficient buildings. A variety of building products with automatic features are being developed, and electronic building systems and computerized building components are being manufactured. Virtually all buildings being built today are equipped with some degree of advanced technologies: for example, electronic control devices and communication systems, automated building facilities, and office automation facilities. This paper outlines the current status of intelligent building technologies. Key features are presented, and the architectural issues associated with the incorporation of the new technologies are discussed. Particular emphasis is given to examining technological advances in daylighting, electric lighting, and HVAC systems. Although these technologies are being incorporated in intelligent buildings throughout the world, specific examples in Japanese buildings are presented to illustrate their implementation in building design.