【正文】 and productivity, cost, and project duration will be improved. Similarly, good practices using the unified approach will improve the project outes through more effective planning, particularly with respect to the interdependencies between project views. The process would be approximately as follows: ? The project management team would define the project views to be used on the project. ? Project planning would be carried out much as on a typical project, except that the results would be represented using the defined project views. This would result in lists or breakdown structures for the project phases, workflows/tasks,deliverables, etc. This would be analogous to a typical project scheduling process, where the results are represented in a CPM work. ? The key interrelationships between the views would be defined. This would be analogous to the way that precedence relationships are captured in a schedule, or the way that a schedule can be mapped to cost accounts, resource plans, or to a building information model (as in the case of 4D CAD). Other than the precedence relationships, this type of mapping is not typically done in current project management practices, so it represents some additional work for project planners. However, it need not be done at a very detailed level, and the use of hierarchical relationships and effective planning tools may minimize the effort required for this task. ? The execution of the resulting plan (., initiating work tasks), project controland feedback (collecting progress information and monitoring results), and replanning activities all take place using the representational framework. Work tasks themselves remain essentially unchanged, but because the planning and management system explicitly captures the interrelationships, the causal links between actions will be better recognized and understood, and the potential negative impacts of any action will be identified earlier and mitigated or avoided more easily. For example, in the case of the change in the intended use of some space in a building mentioned previously, the threads of the causal impacts of this change may be more easily traced through the design,construction, procurement, time, and financial aspects of the project—appropriate adjustments can be made in advance, rather than allowing the impact to propagate as a series of unanticipated, reactionary actions. ? As with scheduling, detail is important, but not all detail is required in advance. Planning for each view might be carried out at a summary level initially, with greater detail add。 there will be more certainty about the timing of events。 they should not be treated as isolated, independent activities. Software Engineering and the Unified Modeling Language. Although project management has a much longer (and perhaps more successful) history within the field of AEC/FM than in the field of software engineering, there are some valuable lessons that AEC/FM can learn from developments in the software industry, particularly related to integrated information structures for managing projects. Much of the software engineering munity has consolidated around the Unified Modeling Language (UML) (Object Management Group, 2021), a standard language for representing the ponents involved in the design and implementation of software projects. The UML provides a much more uniform and integrated (if less prehensive) view of project requirements, processes, and elements, than parable representations within AEC/FM (., project plans and specifications, construction schedules, etc.). Furthermore, UMLbased software development methodologies have emerged (., the Unified Process, Kendall, 2021) that tightly integrate the various project workflows with the various project artifacts (deliverables) throughout each phase of the project lifecycle. These methodologies also accentuate the cyclical and repetitive nature of the related work tasks that are carried out within workflows as they move through the phases of the project lifecycle. Unlike approaches that treat each activity as an independent, onetime task, this reinforces attempts to continually improve performance in this work. While these techniques are not directly applicable to the AEC/FM industry, some of the approaches and best practices are quite relevant. A Unified Approach to Project Management We have argued that existing project management practices underemphasize the interrelationships between individual work tasks and other project ponents. This leaves the interdependencies underrecognized and undermanaged, and promotes a “ onetime event” thinking that hinders the quest for ongoing performance improvements. We have begun to conceptualize a unified approach to project management that addresses some of the weaknesses and opportunities identified above. The basic approach is to adopt a framework that: 1) explicitly represents the various views that are critical for managing projects, and 2) explicitly represents the interconnections between these views. Examples of project views include the physical view (“what”), the process view (“how, who, when”), the cost view (“how much”), etc. (Russell and Froese, 1997). If the total collection of project information is thought of as a multidimensional information space, then the views define the dimensions. For each view, the overall project can be broken down into smaller elements. The simplest representation of a view would be a list or hierarchical breakdown structure of the elements that make up the view (., a work breakdown structure, WBS). More plex representations would capture additional relationships between the elements, such as a CPM work or an IFC model. Primary Views. There are many views that can be useful for managing projects. To act as a unifying management tool, however, these views shoul