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Building information modelling (BIM) technology has been focusing on the creation, sharing and use of a comprehensive digital twin of the facility under construction or renovation. It is believed that a more comprehensive, structured and complete model would be better. The aim of this paper and the underlying research is to reaffirm the view that the essence of information is to inform the user and that the main purpose of information models is that they are informative – that they contain the necessary information. Parsimonious information is information that is necessary but as simple as possible. Our hypothesis is that in many cases simpler models could be more useful, as they do not introduce technological barriers with the usually involved low- and medium-level contractors. One such case is the energy retrofitting of existing buildings. Many public and residential buildings with poor energy performance are located all over the world, especially in Eastern and Central Europe, as well as in China. They are an efficient target for a significant improvement in their energy performance by improving the building envelope and openings. The paper presents an economical process model for the modernisation of existing buildings. This model provides a basis for a parsimonious product model, which is currently under development. The broader objective of the research presented is to examine cases where a heavy information model may not be necessary and where a detailed process definition – as described in the BIM implementation plan and related documents – would lead to over-specification that would limit the free dynamics of a workflow. Tehnologija informacijskega modeliranja stavb (BIM) se osredotoča na ustvarjanje, izmenjavo in uporabo celovitega digitalnega dvojčka objekta, ki se gradi ali prenavlja. Menijo, da bi bil celovitejši, bolj strukturiran in popoln model boljši. Namen tega prispevka in raziskave, na kateri temelji, je ponovno potrditi stališče, da je bistvo informacij obveščanje uporabnika in da je glavni namen informacijskih modelov, da so informativni - da vsebujejo potrebne informacije. Parsimonične informacije so informacije, ki so potrebne, vendar čim bolj preproste. Naša hipoteza je, da bi lahko bili v številnih primerih preprostejši modeli bolj uporabni, saj ne uvajajo tehnoloških ovir z običajno vključenimi izvajalci na nizki in srednji ravni. Eden od takih primerov je energetska prenova obstoječih stavb. Veliko javnih in stanovanjskih stavb s slabo energetsko učinkovitostjo je po vsem svetu, zlasti v vzhodni in srednji Evropi ter na Kitajskem. So u činkovit cilj za znatno izboljšanje njihove energetske učinkovitosti z izboljšanjem ovoja stavbe in odprtin. V članku je predstavljen ekonomski model procesa za posodobitev obstoječih stavb. Ta model je osnova za enostaven proizvodni model, ki se trenutno razvija. Širši cilj predstavljene raziskave je preučiti primere, v katerih težak informacijski model morda ni potreben in v katerih bi podrobna opredelitev procesa - kot je opisana v načrtu za izvajanje BIM in povezanih dokumentih - vodila v pretirano specifikacijo, ki bi omejila prosto dinamiko delovnega procesa

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Based on the overhanging beam three-point bending method, the experimental system was set up to measure the variety of shear stiffness of Nomex honeycomb sandwich panel in laser irradiation. The shear stiffness of the specimens under different laser power density was measured. The result shows that the thermal effect during the laser irradiation leads to the degradation of mechanical properties of Nomex honeycomb sandwich panel. High temperature rise rate in the specimen is another main reason for the shear stiffness degeneration. This research provides a reference for the degradation of mechanical properties of composite materials in laser irradiation and proposes a new method for the study of laser interaction with matter.

The purpose of this paper is to investigate the possibilities and methods of applying the IFC (Industry Foundation Classes) standard, i.e. the mainstream standard of BIM (Building Information Modeling) data to the construction cost estimating for tendering in China. Through analyzing the existing standards and the IFC standard, the problems of using the IFC standard are identified and the solutions are explored. An information requirement model for construction cost estimating for tendering in China was established, which includes seven aspects of information entities. Then each aspect of the information was expressed by using the IFC standard to verify the completeness of the IFC standard and to establish the IFC-based information model. As a conclusion, the IFC standard can be used to express the information for the construction cost estimating for tendering in China as a whole, but some extensions in the form of proxy elements and property sets are needed. The established information model can be applied to the development of a construction cost estimating software.

In order to research the dynamic process of energy coupling between an incident laser and a carbon fiber/epoxy resin composite material, an extinction characterization analysis of soot, which is produced by laser ablating and located in an air flow that is tangential to the surface of the composite material, is carried out. By the theory analyses, a relationship of mass extinction coefficient and extinction cross section of the soot is derived. It is obtained that the mass extinction coefficients of soot aggregates are the same as those of the primary particles when they contain only a few primary particles. This conclusion is significant when the soot is located in an air flow field, where the generations of the big soot aggregates are suppressed. A verification experiment is designed. The experiment employs Laser Induced Incandescence technology and laser extinction method for the soot synchronization diagnosis. It can derive a temporal curve of the mass extinction coefficient from the soot concentration and laser transmittance. The experiment results show that the mass extinction coefficient becomes smaller when the air flow velocity is higher. The reason is due to the decrease of the scatter effects of the soot particles. The experiment results agree with the theory analysis conclusion.

Construction projects typically involve a large number of documents, which are exchanged among multiple parties, including the owner, contractors and engineers. Based on the data warehousing technique, this study presents a method which can utilize electronically exchanged documents among project participants for decision support. A prototypical system called EXPLYZER is developed and tested through its application in a construction project.

With the application of information technology, many parties involved in construction projects have turned to handle the management information using computer systems among themselves, while they still exchange information on papers between them. It has introduced such deficiencies as inefficiency of collaboration and re-entry of data in the management of construction projects. This study aims to develop a system for the parties in construction projects to collaborate on Web to improve the management of the exchanged information. In this paper, the characteristics of the exchanged information in construction projects in China are summarized based on the literature survey and field investigation, and a Web-based approach to developing a system for the management of exchanged information in construction projects is proposed. Then the prototype system that we have developed by using the latest information technologies including eXtensible Markup Language (XML) is examined and its applicability is discussed.

The cladding for high-rise office buildings, often in panel form, has gained increasing popularity in the past two decades. Due to the large number of the cladding panels and brackets and their types, the in-batch arrival of the materials in the warehouse and the delivery from the warehouse to the construction site, it is a rather complex and tedious work to manage cladding construction up to now. This study focuses on developing an integrated approach to facilitating efficient and effective management of cladding construction. According to the approach, two application programs are developed for the construction site management and the warehouse control, respectively, and integrated with e-mail software to form a system. By the system, the cladding materials are identified semi-automatically from the shop drawing files and their attributes such as position and arrival state are stored in a relational database in the construction site. The arrival information of the materials is input or imported and stored in a relational database in the warehouse and the incremental part of the information in the database is sent through e-mail to the construction site management to update the database in the construction site. A prototype system has been developed and it was verified through a large building project. The approach was proved to be more practical, efficient and effective than the current practice.

本研究では, 道路へのCALS適用のために, 既存の個別機能ソフトと新たに開発した専用グループウェアなどのソフトを有機的に統合するシステム化について検討を行っている. 本論文では, まず作成した専用グループウェアのプロトタイプの概要を説明し, またそれを用いたケーススタディを示す. これによって, 本専用グループウェアが道路のライフサイクル情報を構造化して管理でき, 情報管理がより柔軟になり, 作業効率を向上させることができるだけでなく, 今後必要となるライフサイクル道路情報処理の可能性も示す.

The experimental setup was established for studying damage effects on silicon photoelectric detector materials induced by 800nm and 150fs repetitively-pulsed laser. The detector is irradiated by single shot and multiple shots respectively. The laser damage thresholds of silicon photoelectric detector material were measured. The surface morphologies of the material damaged by laser were analyzed. The surfaces damaged by laser with different energy were compared. The thresholds vary with the number of laser shots. According to the accumulation theory, the damage threshold is the power function of the shot number. Experimental results show that threshold of single shot that damages the silicon photoelectric detector is 0.156J/cm 2 . The laser damage threshold decreases with the increasing number of laser pulses, but the minimum value exists. The damage is mainly caused by the mechanical effect rather than thermal effect. In fact, the thermal effect during the interaction is so small that it can’t even be observed. Resistivity of the silicon photoelectric detector irradiated by femtosecond laser decreases and finally tends to a constant value.

The laser coupling effect of material is a fundamental factor to influence laser interaction with matter. The coupling coefficient, which is the material absorptance of the input laser energy, depends on the surface conditions of materials, such as temperature, incident angle, surface airflow, oxidizing environment, and so on. To measure the laser coupling characteristics of materials, two typical online measuring apparatuses were developed in our laboratory. One is based on a conjugated hemi-ellipsoidal reflectometer, which is suitable to measure the laser coupling coefficients of different temperature in vacuum and air environments. The other is based on an integrating sphere and a simple airflow simulator, which can be applied to online measure the laser absorptance of materials subjected to surface airflow. The laser coupling effects on two types of structural materials, which are alloy steels and composite materials, are given in this paper. With the conjugated ellipsoidal reflectometer, the laser coupling effects on a typical alloy steel are investigated in different temperatures under the vacuum and air environment, and the experimental results are analyzed. According the results, metal oxidization plays a key role in the laser coupling enhancement effects. Especially, when the metal is subjected to high power laser irradiation in the high subsonic airflow, metal oxidization which is an exothermic reaction enhances the laser damage effect and the convective heat loss is negligible. Finally, the laser coupling effects on a typical composite material subjected to airflow are studied by using the integrating sphere with an airflow simulator, and the experimental results of laser absorptance during the laser ablation are presented.

In the current way for construction cost estimating by using application software in China, the generation of bill of quantity usually needs plenty of manual work, because the design results cannot be used directly. BIM (Building Information Modeling) technology has provided a potential approach to generating bill of quantity more efficiently by utilizing the computable and reusable information which is available from the 3D design results. However, while several commercial application software have already existed in foreign countries, no BIM-based software in this aspect has been developed in China. In addition, the existing BIM-based application software cannot be directly used in China because they do not support Chinese standards. In this paper, through analyzing the related Chinese standard, a discrimination model for bill of quantity (short for BQ) items was established and the corresponding rule database and semantic database were created. Then the IFC-based discrimination model for BQ items was established and the mechanism of intelligent generation of bill of quantity from IFC data was formulated. Finally the mechanism was programmed and verified through an actual project. As a conclusion, the established mechanism can not only be applied to the development of BIM-based construction cost estimating application software subject to Chinese standard, but also can be referred to develop IFC-based construction cost estimating application software for different countries.

A comprehensive framework of information management system for construction projects in China has been established through extensive literature survey and field investigation. It utilizes the potential information technologies and covers the practical management patterns as well as the major aspects of construction project management. It can be used to guide and evaluate the design of the information management systems for construction projects in order to make the system to be applicable to a wide variety of construction projects and survive the changes in project management.

Publisher Summary This chapter focuses on the reuse of the information that is accumulated in construction projects by using electronic project information management system (EPIMS). In EPIMS, three types of information are dealt—report form, reference to report form, and appendix documents. Among them, the report form corresponds to the traditional ones, while the reference to report form and appendix documents correspond to the traditional appendix documents, because a copy of the report form has to be appended when it is used as an appendix. A hybrid scheme of database structure is used to store the three types of information in the system. XML files and relational database are used to store the first two types of information, and normal files such as Microsoft Word files are used to store the last type of information. The information accumulated in the construction phase normally includes documents. When a project is completed, participants need to extract relative information from the database that contains these documents and conserve it as construction archives for information reuse. This demand is driven mainly by two aspects—companies want to preserve the relative documents for future reference, and the government forces the owner to submit construction comprehensive information in order to preserve construction evidence, and use it in the urban management.

There is considerable interest internationally in developing product libraries to support the use of BIM. Product library initiatives are driven by national bodies, manufacturers and private companies who see their potential. A major issue with the production and distribution of product information for BIM is that separate library objects need to be produced for all of the different software systems that are going to use the library. This increases the cost of populating product libraries and also increases the difficulty in maintaining consistency between the representations for the different software over time. This paper describes a project which uses “software transformation” technology from the field of software engineering to support the definition of a single generic representation of a product which can then be automatically converted to the format required by receiving software. The paper covers the current state of implementation of the product library, the technology underlying the transformations for the currently supported software and the business model for creating a national library in Australia. This is placed within the context of other current product library systems to highlight the differences. The responsibilities of the various actors involved in supporting the product library are also discussed.

The Construction industry accounts for a tenth of global GDP. Still, challenges such as slow adoption of new work processes, islands of information, and legal disputes, remain frequent, industry-wide occurrences despite various attempts to address them. In response, IT-based approaches have been adopted to explore collaborative ways of executing construction projects. Building Information Modelling (BIM) is an exemplar of integrative technologies whose 3D-visualisation capabilities have fostered collaboration especially between clients and design teams. Yet, the ways in which specification documents are created and used in capturing clients' expectations based on industry standards have remained largely unchanged since the 18th century. As a result, specification-related errors are still common place in an industry where vast amounts of information are consumed as well as produced in the course project implementation in the built environment. By implication, processes such as cost planning which depend on specification-related information remain largely inaccurate even with the use of BIM-based technologies. This paper briefly distinguishes between non-BIM-based and BIM-based specifications and reports on-going efforts geared towards the latter. We review exemplars aimed at extending Building Information Models to specification information embedded within the objects in a product library and explore a viable way of reasoning about a semi-automated process of specification using our product library.