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An alternative approach to understanding innovation is made using two intersecting ideas. The first is that successful innovation requires consideration of the social and organizational contexts in which it is located. The complex context of construction work is characterized by inter-organizational collaboration, a project-based approach and power distributed amongst collaborating organizations. The second is that innovations can be divided into two modes: 'bounded', where the implications of innovation are restricted within a single, coherent sphere of influence, and 'unbounded', where the effects of implementation spill over beyond this. Bounded innovations are adequately explained within the construction literature. However, less discussed are unbounded innovations, where many firms' collaboration is required for successful implementation, even though many innovations can be considered unbounded within construction's inter-organizational context. It is argued that unbounded innovations require an approach to understand and facilitate the interactions both within a range of actors and between the actors and technological artefacts. The insights from a sociology of technology approach can be applied to the multiplicity of negotiations and alignments that constitute the implementation of unbounded innovation. The utility of concepts from the sociology of technology, including 'system building' and 'heterogeneous engineering', is demonstrated by applying them to an empirical study of an unbounded innovation on a major construction project (the new terminal at Heathrow Airport, London, UK). This study suggests that 'system building' contains outcomes that are not only transformations of practices, processes and systems, but also the potential transformation of technologies themselves.  相似文献   
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The study revealed that Fixed Price, Cost Plus and Purchased Labour contracts are the top three maintenance contracts adopted whilst Unit Price, Cost Plus A Percentage Fee contracts are alternatives used in the Kingdom. Some other types of maintenance contract were thought to be inappropriate by ministry departments.  相似文献   
4.
The widening of interest and scope of property management and maintenance has attracted a greater diversity of professional disciplines into facilities management. Dr Quah, coordinator of CIB W70 on Management, Maintenance and Modernization of Building facilities, expresses her personal views on the current fascination with the subject.  相似文献   
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Compression-after-impact (CAI) tests have been conducted for quasi-isotropic thick plates with 48 plies by using the NASA method and on plates with 32 plies by using the SACMA method. Specimens are made of CF/PEEK (APC-2) and conventional CF/epoxy for the NASA plates and CF/epoxy for the SACMA plates. In the NASA CAI tests, the sequence of delamination buckling and its propagation is clearly revealed through various experimental techniques. One major technique is moiré topography, and the other is thermo-mechanical stress analysis with a high-accuracy infrared sensor. The arrest of delamination propagation just before catastrophic failure due to high fracture toughness is clearly captured by the moiré camera. This behavior provides good CAI values of CF/PEEK. The initial buckling properties of the delaminated region by the impact are then extensively discussed. Numerical predictions of initial buckling stress have been obtained by modelled geometry of the delaminated region simplified from its precise structure clarified by ultrasonic C-scanning. They agree fairly well with the experimental results. The in-plane stress distribution in the delaminated region before initial buckling is measured by an infrared stress graphic system. This compared favorably with finite element predictions. Two types of symmetric buckling modes with respect to the central plate surface, twin and single peak ones, are experimentally captured.  相似文献   
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The architects and builders in the past lacked our knowledge concerning fluid dynamics, but they exhibited a deep rooted ability to observe and reflect - thus, different cultures have developed by trial and error. The authors have produced a stimulating analysis which couples the science of fluid dynamics and a sensitive understanding of past cultures. The paper is recommended reading.  相似文献   
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During the winter of 1988/1989, the relationships between the prevalence of work-related health and indoor climate complaints and a number of building, management, workplace and personal characteristics have been investigated in a study in more than 60 office buildings located throughout the Netherlands. To collect the information, a questionnaire was prepared on health and indoor climate complaints and personal and workplace characteristics. A checklist was used to obtain information on building characteristics More than 7000 questionnaires were completed by the regular users of the buildings investigated. The results showed that the prevalence of symptoms was higher in air-conditioned buildings than in naturally or mechanically ventilated buildings. some other variables were also related with most work-related complaints after adjustment for selected management, personal, workplace and job characteristics. These included gender, work satisfaction in general, presence of allergies and/or respiratory symptoms, and personal control over temperature at the workplace. No differences were found in symptom prevalences between buildings with spray and steam humidification. The combination of air-conditioning and humidification did not lead to further increases in the prevalence of complaints as compared to buildings with only airconditioning or only humidification.  相似文献   
9.
Service life planning comprises a model for the determination of a reasonable expected service life for buildings and components, and it establishes a routine for the assessment of design alternatives. A design option is considered reasonable when it meets or exceeds performance requirements over time that have been drawn up specifically for the specific project. Due to this assessment reference, there is a very evident link to the concept of performance-based building. Any stakeholder involved in the value chain or in the design process of the building, as well as regulators and building users, can express performance requirements. Identified requirements, both in relevance and in quality, will vary with the stakeholder and his/her perspective of interest. As building sector manufacturers develop most products with reference to standards rather than with reference to specific requirements, there is no direct link from user requirements to the product design. Instead, the building designer has the responsibility to ensure performance requirements are met by the performance of products integrated into the design. As these design decisions also have to be made at the material and component level, a performance-based building would benefit from an established rationale that enables the communication of performance requirements across the relevant system levels in the relevant design processes. A path for the connection of the established concepts of service life planning and performance-based building is presented. The aim is to identify key elements that need to be developed for the successful linkage of performance-based building with service life planning.  相似文献   
10.
Istanbul is one of the most famous historical cities in the world. However, the project alignment selected as the best of a range of alignments cannot avoid passing beneath the historical and cultural heritages of Istanbul as well as under ancient and densely inhabited areas of the city. This paper will explain some of the challenges related to the bored tunnels.

Historical buildings are vulnerable. Yet many existing residential and office buildings are old and constructed on minimal foundations. As a consequence, it is vital that any drawdown of groundwater and any ground settlements have to be minimized.

In addition, the connection between the immersed and bored tunnels will be made directly and totally underground, without the usual intermediate shafts and beneath the deep waters of the Bosphorus Strait. This operation needs the utmost control of the tunnel excavation face to ensure its stability and to minimize water ingress. Based on such considerations, tunnel excavation by tunnel boring machine (TBM) using a slurry shield and having the ability to operate under high pore pressures was recommended as the method of excavation for the main running tunnels.

The paper will explain how the design team from Avrasyaconsult – the Employer’s Representative – arrived at the final minimum, specific and functional requirements of the bored tunneling works which are to be carried out using the ‘FIDIC EPC/Turnkey Project’ conditions.  相似文献   

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