Green Low-Carbon Technology for Metalliferous Minerals

Metalliferous minerals play a central role in the global economy. They will continue to provide the raw materials we need for industrial processes. Significant challenges will likely emerge if the climate-driven green and low-carbon development transition of metalliferous mineral exploitation is not managed responsibly and sustainably. Green low-carbon technology is vital to promote the development of metalliferous mineral resources shifting from extensive and destructive mining to clean and energy-saving mining in future decades. Global mining scientists and engineers have conducted a lot of research in related fields, such as green mining, ecological mining, energy-saving mining, and mining solid waste recycling, and have achieved a great deal of innovative progress and achievements. This Special Issue intends to collect the latest developments in the green low-carbon mining field, written by well-known researchers who have contributed to the innovation of new technologies, process optimization methods, or energy-saving techniques in metalliferous minerals development

Reverse supply chain conceptual model for construction and demolition waste

Construction and demolition waste (CDW) substantially contributes to environmental degradation because of its intrinsic characteristics of fast and high generation volume, low recycling rate, and low revenue margins. A systemic problem is that recycling facilities are not usually a part of a reverse supply chain (RSC) specific for CDW. This makes the recovery process costs prohibitive, especially where companies are unable to receive and process large volumes of waste continuously. This paper presents a systematic analysis of the extant literature and utilizes the results accrued to develop a conceptual RSC model for CDW. In so doing, the research seeks to provide clarity on this phenomenon, while simultaneously stimulating wider academic discourse and further research endeavours. A mixed philosophies epistemological design was adopted using both interpretavism and constructivism to undertake a qualitative systematic analysis of the literature. A process diagram was produced to represent the conceptual model (CM) and thematically group the nodes into three key swim lanes that delineate the boundaries between distribution, manufacturing, and sourcing and warehousing processes. Within each swim lane, stakeholders were incorporated as key actors. A further layer of nuanced complexity was added to illustrate the key actors involved in the process, government strategies, and activity flow paths. This novel CM offers both practical and theoretical contributions to existing knowledge and signposts a future research direction. Such work will demystify reverse logistics for managing CDW, and assist government policy-makers to develop informed policies that reduce the negative environmental impact of construction activities

Technology and Management for Sustainable Buildings and Infrastructures

A total of 30 articles have been published in this special issue, and it consists of 27 research papers, 2 technical notes, and 1 review paper. A total of 104 authors from 9 countries including Korea, Spain, Taiwan, USA, Finland, China, Slovenia, the Netherlands, and Germany participated in writing and submitting very excellent papers that were finally published after the review process had been conducted according to very strict standards. Among the published papers, 13 papers directly addressed words such as sustainable, life cycle assessment (LCA) and CO2, and 17 papers indirectly dealt with energy and CO2 reduction effects. Among the published papers, there are 6 papers dealing with construction technology, but a majority, 24 papers deal with management techniques. The authors of the published papers used various analysis techniques to obtain the suggested solutions for each topic. Listed by key techniques, various techniques such as Analytic Hierarchy Process (AHP), the Taguchi method, machine learning including Artificial Neural Networks (ANNs), Life Cycle Assessment (LCA), regression analysis, Strength–Weakness–Opportunity–Threat (SWOT), system dynamics, simulation and modeling, Building Information Model (BIM) with schedule, and graph and data analysis after experiments and observations are identified

Hybrid Simulation for Construction Operations

Developing realistic and unbiased simulation models for construction operations require addressing the operational and strategic decision making levels. The dynamics and feedback processes observed in construction systems are responsible for the real behavior of such systems and drive the needs for hybrid and integrated simulation tools. The dominant simulation methods such as discrete event simulation (DES) and system dynamics (SD) are limited individually of capturing all the significant construction operation aspects that are responsible for generating the behaviour of realistic models. Therefore, this thesis presents a hybrid simulation method for simulating construction operations by utilizing the joint powerful features of the DES and SD methods. The proposed method provides a framework to integrate DES and SD on single computational platform. Developing a hybrid simulation model commences by decomposing the construction project into units, form which simulation models (e.g. DES or SD) are developed. A unidirectional variables interaction from DES to SD models is used. The interfacing process among simulation models is achieved by defining three variables: sender, interface, and receiver. The mechanism that controls data mapping processes between variables is outlined in a new developed synchronization method. The variables interaction protocol is described using formalism. Finally, a Hybrid Simulation Application (HiSim) is coded in VB.NET to demonstrate a sequential implementation of the developed method. A real-world earthmoving project is modeled and simulated to test the developed hybrid simulation method. The hybrid simulation structure uses unidirectional and sequential interactions between the components of DES and SD models. The simulation is run under three scenarios, is able to predict the real project completion duration with 92% accuracy, and captures the influences of the context level variables. The findings are expected to enhance hybrid simulation applications in construction and to allow for better understanding of the impact of various internal and external factors on the project schedule and its productivity performance

Ground Forces: Dirt, Demolition, and the Geography of Decline in Detroit, Michigan

This dissertation contributes to the study of the production of urban decline by examining the process of demolishing. Recent research on the production of urban decline, by focusing on the property and real estate practices of speculation, foreclosure, and eviction, has provided an analytical framework for identifying and interpreting the persistent shifts in capital accumulation strategies that produce blight. The property and real estate practices of demolition extend beyond the site of a demolished building and reinforce processes producing urban decline. Demolishing depends on environments, logistics, policies, and resources that preserve regional geographies of uneven development. I investigate the Detroit Demolition Program (DDP) and efforts between 2013 and 2019 to demolish over 40,000 houses in Detroit, MI. I study this city and its program to question and interpret relationships between demolition and urban decline. In existing research, local public policy authorizes and pays contractors to deliver on-demand demolition to an abandoned building. Based on interviews and my analysis of public documents, DDP data, and sites, I show this focus on the practice of demolition erases the processes and effects of demolishing that extend beyond an address. Demolition is part of the production of urban decline and includes supply chains, forms of value, resources, property relations, and environments that conflict with demolition as an intervention against decline. The process of demolishing Detroit depended on the emergence of a consensus turning blight into an emergency and removal into a necessity. Public, private, and philanthropic interests linked demolition to revitalization but also used it served regulatory, political, and financial goals. The urgency around demolishing provided justification for DDP policies that accommodated the income-generation priorities of contractors. The DDP depended on contractors sourcing millions of cubic yards of dirt and rock to grade holes after basement excavation. Shifting DDP regulation on backfill ensured demolition was lucrative for wreckers and their networks. Backfilling Detroit meant millions of dollars in transactions that served contractors and suburban development agendas. Contractors sourced material from 444 unique sources, including luxury condos and retailer parking lots. The transformation of Detroit's built environment through demolition relied on continued regional expansion that converted wastes of growth into assets for destruction. Demolishing Detroit was not an intervention slotted between periods of decline and development. Instead, demolishing was a value-extraction process manifesting land uses and property practices that generated income without redevelopment. Contractors engendered a regional land regime that could produce and sustain demolition. Instead of an interruption in the production of urban decline, making land vacant and ready for profitable intensification, demolishing Detroit was the continuation of decline by a different means. This dissertation shows the limits of research on demolition that relies on the potential for reuse to evaluate consequences for neighborhoods. These dichotomies separate demolishing from the conditions and contradictions of its creation. By illustrating how demolishing is part of the process of decline I provide an alternative to research that conceals the operations of capital by relying on divides between global and local, between causes and interventions. Rather than managing decline or prompting redevelopment, demolishing is one process by which capitalist urbanization achieves the extraction of value in shrinking cities. Extending these insights beyond Detroit and demolition can identify local responses that may appear to manage decline but through their environmental and logistical processes reinforce regional segregation and produce decline.PHDUrban and Regional PlanningUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/162864/1/mkosciel_1.pd