Browsing by Subject "Life cycle"

Now showing 1 - 3 of 3

Embargo
Cybernetic-parsimonious MCDM modeling with application to the adoption of Circular Economy in waste management
(Elsevier, 2023-05-01) Kabirifar, K.; Ashour, Mojtaba; Yazdani, M.; Mahdiyar, A.; Malekjafarian, M.
Construction and demolition waste (CDW) is the main contributor to economic loss, environmental pollution, and health hazards if the current linear economy model of ‘take-make-consume-dispose’ is not replaced by a Circular Economy (CE) as a solution approach to maximize the use of resources and reduce waste. However, successful CE concept implementation involves strategies that trigger construction and demolition waste management (CDWM) throughout its life cycle, rather than end-of-life strategies, such as reuse and recycling. By meticulously reviewing the literature, nineteen factors that affect CDWM from CE concept implementation throughout six stages of preconstruction, procurement, construction, demolition, transportation, and end-of-life are initially identified. A hybrid fuzzy Multi-Criteria Decision-Making approach is then utilized in two main stages, including an Enhanced Fuzzy Delphi Method in stage one, to refine the identified factors according to Tehran's construction context, and a Cybernetic Parsimonious Fuzzy Analytic Hierarchy Process in stage two, to prioritize these factors. Three factors were identified during the first stage of the research methodology and added to the factors extracted from the literature. The results indicate that ‘on-site sorting, reusing, and recycling of waste materials’, ‘various procurement models’, and ‘precise implementation of waste management regulations and plans’ are the most important factors, respectively. A comprehensive list of the factors provided as part of the research findings has contributed to the body of knowledge to be used as a snapshot by researchers, while the ranking of the factors gives new insights to stakeholders on ways to manage CDW in projects.
Open Access
Fluid futures of multi-layered histories: many lives of north brother island, New York City
(Universidad de Oviedo, 2023-07-29) Erdoğan, Meriç
The transience of populations reflects itself as the life cycle of the buildings. Constantly changing dynamics in the entities of a building also constantly effects the fate of the structure. Even with the proper treatment, the loss of its compatibility in functions with the deterioration of a structure becomes inevitable with the forces of various humanitarian, natural and ecological crises. The examined case that has experienced several phases of ephemerality in its lifetime is the North Brother Island in NYC that people abandoned more than half a century ago. In its many lives, the island has been a quarantine island, the site of one of the deadliest maritime accidents, a last resort housing solution for WWI veterans, and a forced rehabilitation center for young drug addicts. Today the island is occupied with a few abandoned public buildings, which are remnants of its troublesome past, and innumerable plants that have taken over the land after everyone left. And now it is facing its proclaimed sinking that is going to be happening in 100 years. This project is for the treatment of a more than human community in the isolated jungle off the coast of the dense cosmopolitan NYC. In an era defined by the environmental and climatic crises, architecture's long-standing obsession with monumental and immortal buildings has to leave a way for a humbler approach intending to provide habitats for more than one entity in the cycle of life. The design method to answer this problem is to consciously re-creating places on the island by using de-constructed materials from the former buildings of the island with the addition of biodegradable ones. By their dissolving in nature after the sinking, only the skeletons of the structure will remain as a ruin, but also as a new home for underwater life. In conclusion, this approach envisions a safe environment for nature and humans through the different stages of the island until the inevitable yet not to be feared sinking of the island, which will further become the starting point of the new urban infrastructure of underwater life.
Open Access
Optimal timing of project control points
(Elsevier, 2000) Raz, T.; Erel, E.
The project control cycle consists of measuring the status of the project, comparing to the plan, analysis of the deviations, and implementing any appropriate corrective actions. We present an analytical framework for determining the optimal timing of project control points throughout the life cycle of the project. Our approach is based on maximizing the amount of information generated by the control points, which depends on the intensity of the activities carried out since the last control point and on the time elapsed since their execution. The optimization problem is solved with a dynamic programming approach. We report the results of numerical experimentation with the model involving different types of activity intensity profiles and several levels of information loss. For each combination, we compared the optimal amount of information to the amount of information obtained with two simpler policies: control at equal time intervals, and control at equal activity contents intervals. We also investigated the effect of adding more control points on the amount of information generated.