Cities emit extensive carbon emissions, which are considered a major contributor to the severe issue of climate change. Various low-carbon development programs have been initiated at the city level worldwide to address this problem. These practices are invaluable in promoting the development of low-carbon cities. Therefore, an effective approach should be developed to help decision makers select the best practices from previous experience on the basis of the impact features of carbon emission and city context features. This study introduces a case-based reasoning methodology for a specific city to select the best practices as references for low-carbon city development. The proposed methodology consists of three main components, namely, case representation, case retrieval, and case adaption and retention. For city representation, this study selects city context features and the impact features of carbon emission to characterize and represent a city. The proposed methodology is demonstrated by applying it to the selection of the best practices for low-carbon development of Chengdu City in Sichuan Province, China.
Real-time decision making reflects the convergence of several digital technologies, including those concerned with the promulgation of artificial intelligence and other advanced technologies that underpin real-time actions. More specifically, real-time decision making can be depicted in terms of three converging dimensions: Internet of Things, decision making, and real-time. The Internet of Things include tangible goods, intangible services, ServGoods, and connected ServGoods. Decision making includes model-based analytics (since before 1990), information-based Big Data (since 1990), and training-based artificial intelligence (since 2000), and it is bolstered by the evolving real-time technologies of sensing (i.e., capturing streaming data), processing (i.e., applying real-time analytics), reacting (i.e., making decisions in real-time), and learning (i.e., employing deep neural networks). Real-time includes mobile networks, autonomous vehicles, and artificial general intelligence. Central to decision making, especially real-time decision making, is the ServGood concept, which the author introduced in an earlier paper (2012). It is a physical product or good encased by a services layer that renders the good more adaptable and smarter for a specific purpose or use. Addition of another communication sensors layer could further enhance its smartness and adaptiveness. Such connected ServGoods constitute a solid foundation for the advanced products of tomorrow which can further display their growing intelligence through real-time decisions.
Quality function deployment (QFD) is an effective method that helps companies analyze customer requirements (CRs). These CRs are then turned into product or service characteristics, which are translated to other attributes. With the QFD method, companies could design or improve the quality of products or services close to CRs. To increase the effectiveness of QFD, we propose an improved method based on Pythagorean fuzzy sets (PFSs). We apply an extended method to obtain the group consensus evaluation matrix. We then use a combined weight determining method to integrate former weights to objective weights derived from the evaluation matrix. To determine the exact score of each PFS in the evaluation matrix, we develop an improved score function. Lastly, we apply the proposed method to a case study on assembly robot design evaluation.
One limitation of previous productivity-driven research on equipment selection and operation simulation lies in the fact that the green aspects of construction activities have been largely neglected in analysis of costefficiency of construction operations. On the other hand, studies attempting to measure greenhouse gas emission due to construction activities have yet to develop a methodology that correlates their findings and implications with construction productivity. In order to address the immediate need for improving the sustainability performance of construction projects, it is imperative for the construction industry to evaluate greenhouse gas emission as a cost factor in construction planning, equipment selection, and cost estimating. In this context, this paper formalizes an integrative framework for equipment cost analysis based on the concepts of lean construction and green construction, aimed to guide the selection of appropriate construction equipment considering exhaust emission and productivity performance at the same time. The framework is elaborated in earthwork construction in order to evaluate the impact of greenhouse gas emission in estimating equipment hourly rates and assessing greenness and sustainability for alternative equipment options.
This paper presents 12 dimensions of work with the aim of providing further understanding of the relationship between work and the psychological well-being of workers. Previous research has indicated that these dimensions are significant in establishing such a relationship, which is essential to creating good work. These dimensions are also influential in their effect on the psychological state of workers and are translated specifically into actionable items in the workplace. A hypothetical system model is developed to relate these dimensions to one another, to workers, and to organizations. This set of dimensions also serves as a basis for further development of work design and evaluation tools.
Obsolescence of integrated systems which contain hardware and software is a problem that affects multiple industries and can occur for many reasons, including technological, economic, organizational, and social factors. It is especially acute in products and systems that have long life cycles, where a high rate of technological innovation of the subcomponents result in a mismatch in life cycles between the components and the systems. While several approaches for obsolescence forecasting exist, they often require data that may not be available. This paper describes an approach using non-probabilistic scenarios coupled with decision analysis to investigate how particular scenarios influence priority setting for products and systems. Scenarios are generated from a list of emergent and future conditions related to obsolescence. The key result is an identification of the most and least disruptive scenarios to the decision maker’s priorities. An example is presented related to the selection of technologies for energy islanding, which demonstrates the methodology using six obsolescence scenarios. The paper should be of broad interest to scholars and practitioners engaged with enterprise risk management and similar challenges of large-scale systems.
Despite the growing interest in green products in the interior wall decorative material market, knowledge gaps exist because determining which product is more environmental and user friendly than the others is difficult. This work assesses the environmental and human health profiles of interior latex and wallpaper. Two interior latex products of different raw material ratios and one non-woven wallpaper product are considered. The environmental impact assessment follows life cycle assessment (LCA) methodology and applies Building Environmental Performance Analysis System (BEPAS). The human health impact is based on impact-pathway chain and is performed using Building Health Impact Analysis System (BHIAS). The assessment scope, associated emissions, and territorial scope of various emissions are defined to facilitate comparison study of interior wall decorative products. The impacts are classified into 15 categories belonging to three safeguard areas: ecological environment, natural resources, and human health. The impacts of categories are calculated and monetized using willingness to pay (WTP) and disability-adjusted life year (DALY) and summarized as an integrated external cost of environmental and human health impacts. Assessment results reveal that the integrated impact of interior latex is lower than that of non-woven wallpaper, and the interior latex of low quality causes low life cycle integrated impact. The most impacted categories are global warming, respiratory effects, and water consumption. Hotspots of product manufacturing are recognized to promote green product design.
Many researchers found high potential of adopting building photovoltaic (PV) systems in urban areas, especially on building rooftop, to improve the sustainability of urban environment. However, the optimal energy output performance and economic benefit of the PV system are affected by the usable roof area, PV array layout, and shading effect considering high city density. This study aims to understand the effects of these design parameters in the urban environment of rooftop PV’s economic performance. This study carries out a case study in the urban area of Melbourne with 90 PV designs under three shading conditions to generate 270 scenarios. Through a lifecycle cost-benefit analysis, including net present value (NPV), NPV per kW, internal return rate (IRR), and payback year, the results can help in developing a comprehensive understanding of the economic performance of rooftop PV designs that cover most of the urban areas of Melbourne. The optimal PV design scenarios for the urban environment are identified, thereby providing investors and industry professionals with useful information on value-for-money PV design. Meanwhile, the maximum shading loss that makes the PV systems financially unfeasible is investigated, and design scenarios with greatest ability to sustain the shading effect are identified. This research can also support the policy makers’ decision on the development and deployment of the roof PV systems in urban planning.
Recycled concrete is a material with the potential to create a sustainable construction industry. However, recycled concrete presents heterogeneous properties, thereby reducing its applications for some structural purposes and enhancing its application in pavements. This paper provides an insight into a solution in the deformation control for recycled concrete by adding supplementary cementitious materials fly ash and blast furnace slag. Results of this study indicated that the 50% fly ash replacement of Portland cement increased the rupture modulus of the recycled concrete. Conversely, a mixture with over 50% cement replacement by either fly ash or slag or a combination of both exhibited detrimental effect on the compressive strength, rupture modulus, and drying shrinkage. The combined analysis of environmental impacts and mechanical properties of recycled concrete demonstrated the possibility of optimizing the selection of recycled concrete because the best scenario in this study was obtained with the concrete mixture M8 (50% of fly ash+ 100% recycled coarse aggregate).
Maritime shipping is considered the most efficient, low-cost means for transporting large quantities of freight over significant distances. However, this process also causes negative environmental and societal impacts. Therefore, environmental sustainability is a pressing issue for maritime shipping management, given the interest in addressing important issues that affect the safety, security, and air and water quality as part of the efficient movement of freight throughout the coasts and waterways and associated port facilities worldwide. In-depth studies of maritime transportation systems (MTS) can be used to identify key environmental impact indicators within the transportation system. This paper develops a tool for decision making in complex environments; this tool will quantify and rank preferred environmental impact indicators within a MTS. Such a model will help decision-makers to achieve the goals of improved environmental sustainability. The model will also provide environmental policy-makers in the shipping industry with an analytical tool that can evaluate tradeoffs within the system and identify possible alternatives to mitigate detrimental effects on the environment.