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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.

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.

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.

During the late years there has been an ever-increasing focus on the possibilities to change the building process to raise quality on the final building products as well as the activities of actors involved in the building process. One reason for this interest is the new opportunities evolving due to introduction of advanced information and communication technology (ICT). The paper focuses on creative changes of the building process powered by user driven innovation activities. An overview of existing user driven innovation methodologies is given as well experiences from the ongoing Virtual Innovation in Construction (VIC) project. One important driving force for change is the opportunity for users to develop and articulate real needs concerning for example different functionalities of a building and its parts, but also on artifacts supporting the actual needs capture and requirements formulation during building design. A general methodological framework and meta ontology for Virtual Innovation in Construction is presented as well as findings from implementation of the method. During the late years there has been an ever-increasing focus on the possibilities to change the building process to raise quality on the final building products as well as the activities of actors involved in the building process. One reason for this interest is the new opportunities evolving due to introduction of advanced information and communication technology (ICT). The paper focuses on creative changes of the building process powered by user driven innovation activities. An overview of existing user driven innovation methodologies is given as well experiences from the ongoing Virtual Innovation in Construction (VIC) project. One important driving force for change is the opportunity for users to develop and articulate real needs concerning for example different functionalities of a building and its parts, but also on artifacts supporting the actual needs capture and requirements formulation during building design. A general methodological framework and meta ontology for Virtual Innovation in Construction is presented as well as findings from implementation of the method.