In this issue, Kim proposes a unique schedule-stopping approach as a better alternative to the traditional iteration method. This new method offers improvements in terms of both algorithm effectiveness in finding project duration, and computational time, which is also significant for genetic algorithm optimization. Based on experimental results from the USA, he compares two genetic algorithm (GA) stopping conditions to demonstrate their suitability for application in the resource-constrained project scheduling problem and to assess their ability in searching optimal solutions efficiently. He found that, when using the unique schedule method, the algorithm provides more optimum values than those obtained when using the iteration method with less computational time. The improvement is valuable because many researchers attempt to reduce the average deviation of their solutions against optimal solutions and the algorithm provides more optimum values. The findings can inform GA users to facilitate their purpose driven genetic algorithms for optimization of the resource scheduling problem.
Raisbeck and Tang identify and analyse design development factors in public–private partnership (PPP) projects, having carried out a survey of executives, architects and other professionals working on major PPP projects in Australia. They argue that design-related factors have not previously been given enough attention in PPP research and they seek to position design processes as an innovative area of research within construction management. Raisbeck and Tang were motivated to avoid the ambiguities, subjectivities and disciplinary fault lines that beset design studies in both architectural and construction management research. They argue that construction management researchers should turn to examining the intricate workflows that constitute PPP projects as these better explain the complexities of these projects. To achieve these objectives, analytical hierarchy process (AHP) was used to identify and explore which design development factors are most important in PPP projects. The AHP framework was not used simply as a decision support or selection tool. Raisbeck and Tang discovered that the proactive management of an initial design through the PPP process is crucial. This capability is more important than architects further developing a design or a PPP consortium providing management regimes that ‘tick the boxes’ on a project. Recognizing this capability has implications for future researchers as well as for decision-makers and policy-makers who evaluate PPP bids. More than anything, it affirms the importance of understanding design processes and how designs are developed and managed in PPP projects.
It is often claimed that the construction industry is conservative and non-innovative. Some claim that this is a myth. This question is the starting point for a study by Håkansson and Ingemansson. Their aim was to investigate whether there is any truth to the perceived lack of innovation and, furthermore, what kind of factors might act as drivers or barriers for renewal. A survey of the Swedish construction industry was conducted based on an industrial network approach with the primary focus of analysing the interfaces between construction companies and their different counterparts. The results show a clear connection between the types of interface that characterize the industry and how renewal takes place. The total level of renewal activity is considerable, with more than 60% having made changes during the last five years visible from the customer’s point of view. However, suppliers’ capabilities are not activated as much as customers’ and one reason which the authors identify is the systematic use of competitive bargaining for separate projects. This reduces the possibilities for joint learning and co-evolution in technical and logistical dimensions.
Langston argues that if built infrastructure decisions are to be sustainable, issues of feasibility and desirability need to be expressed in the context of environmental consequences. Rather than treat environmental performance as a positive to be maximized, he demonstrates that there is merit in treating environmental loss as a negative to be minimized. This is an important idea because it enables ratios to be calculated to measure the expected degree of success. Value for money is a measure of feasibility and is defined as the ratio of wealth created (return on investment) compared to resources consumed (energy usage). Quality of life is a measure of desirability and is defined as the ratio of delivered utility (functional performance) compared to ecosystem impact (loss of habitat). Sustainability risk is defined as the scale of the project. Using these values as coordinates in a 3D space, the merits of a decision to proceed can be visualized as the distance between the project coordinate and the ‘high sustainability corner’ or hotspot. Langston tests the model with a case study of a high performance green building in Australia and draws parallels to other generic project types. His approach enables sustainable development to be assessed on the basis of integrated economic, social and environmental criteria and expressed as a single value or sustainability index to aid the decision-making process.
Boudeau examines how the coordination of expertise involved in architectural projects is carried out. This has long been seen as a problem in the context of the complex division of labour that characterizes the industry, which has largely called for formal procedures as a means of simplifying these interactions. Taking up suggestions in the literature to develop an understanding of the manifold dimensions of the industry by attending to actual practices, notably found in the literature on project management, Boudeau addresses specific practices through which the coordination of expertise is achieved. This example concerns the design of a roof garden and focuses on an exchange between a structural engineer and a landscape architect in a moment in a design team meeting. Drawing on sociological approaches concerned with the description of ordinary and routine methods, she shows how the coordination of their expertise was achieved in and through the routine methods constitutive of their conversation. The main finding is that coordination of expertise can happen as part of the natural development of design meetings, something that has been overlooked and, thus, does not necessarily require prescriptive and formal procedures. Therefore, she provides a different way of thinking about the possibility of achieving coordination; one that is grounded in the way that people naturally conduct their affairs.