630,195 research outputs found

    Risk and sustainability assessment (RSA) framework for ‘water scarcity – water reuse’ situations: Conceptualisation, operationalisation, and testing

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    The number of regions undergoing water scarcity, where the quantity of available water is not enough to meet human demand, is expected to increase in the future. Water reuse measures have been widely implemented to face these situations as a means of increasing the supply of water resources. Thus, ‘water scarcity – water reuse’ (WS-WR) situations will likely become more common. In these cases, water resources management to secure enough water supply is key. Risk and sustainability concepts have been consolidated as guiding discourses that also support the management of water resources. In particular, in the case of WS-WR situations, they can guide decision-makers towards reducing the risk of water scarcity and striving for the implementation of sustainable water reuse measures. In particular, the use of risk and sustainability assessments helps to deal with various social, economic, and environmental requirements and constraints. However, there is still the call for a more comprehensive and integrated assessments. This dissertation aims at providing new ideas for the integration of risk and sustainability in the case of WS-WR situations. Three objectives guide this research: (A) to develop a conceptual assessment framework to support decision-making concerning sustainable water reuse in regions facing risk of water scarcity; (B) to advance the conceptual framework interrelating existing risk and sustainability assessment methodologies and indicators in the context of decision support; and (C) to test the conceptual and methodological framework using a case study in Latin America. Each objective is associated with a research question: (RQ1) How is decision-making regarding water reuse understood and supported towards reducing the risk of water scarcity sustainably – and how can it be represented in a conceptual assessment framework?; (RQ2) How can a conceptual framework for assessing water reuse as sustainable water scarcity risk reduction measures be operationalised through a methodological framework?; and (RQ3) What are the findings from testing the framework in a case study – and what can be incorporated into the framework? Each objective and its respective research question was addressed as a separate step of the research approach, comprising the development of an integrated Risk and Sustainability Assessment (RSA) Framework for WS-WR situations, its operationalisation and testing. The research approach followed a deductive to inductive rationale relying on qualitative and quantitative methods. The outputs of this research are three scientific publications that build this cumulative dissertation (two published and one submitted for revision). The development of the conceptual framework followed three steps: (i) defining the concepts of ‘water scarcity’, ‘water reuse’, ‘risk’ and ‘risk assessment’, ‘sustainability’ and ‘sustainability assessment’, and ‘decision-making’; (ii) integrating these concepts by interpreting water scarcity from a risk perspective and water reuse from a sustainability perspective, and relating assessments with decision-making; and (iii) structuring the RSA Framework, following a risk assessment and framing it by the social, economic, and environmental dimensions of sustainability. Results allowed defining decision-making in WS-WR situations as a four-step cyclic process that can be supported by an integrated RSA that comprises an analysis (descriptive and objective) and evaluation (subjective). The methodological aspects for the operationalisation of the RSA conceptual framework focused mainly on developing an analytical concept to support an adequate derivation of the information required in an integrated RSA for WS-WR situations. The resulting concept is based on (i) understanding the WS-WR situation as a Coupled Human and Natural System (CHANS) and identifying the main biophysical elements (endpoints); (ii) translating the CHANS endpoints into an information system via a Multi-Layer (ML) approach using generic descriptors and specific indicators; and (iii) identifying and characterising interlinkages between the indicators via a Lane-Based (LB) approach. Additional methodological aspects related to the evaluation include the use of indicator-based multi-criteria decision-making methods that include the weighting and aggregation of these indicators, as well as the selection of threshold values as evaluation criteria. The testing of the integrated RSA Framework was carried out in Cerrillos de Tamaya, Chile. It involved an ex-post RSA of a water reuse measure implemented in 2018 to face the local water scarcity situation. The testing included (i) describing the case study location and adapting the RSA Framework to fit the local context; (ii) translating the case study’s CHANS via the ML approach and identifying and characterising interlinkages via the LB approach; and (iii) evaluating the degree of risk of water scarcity and sustainability of water reuse via the distance-based method TOPSIS. The results of the testing provided feedback for the RSA Framework. These mainly referred to the influence of the conceptualisation behind the indicators and their use, and the methodological challenges for integrating risk and sustainability evaluation. Further recommendations to the RSA framework are: the inclusion of interlinkage directionality; the use of existing system dynamics modelling approaches (e.g., CLD, SFD); the development of an established database of indicators; the automation of the interlinkages analysis (LB approach); and advance the use of scenarios for sustainability evaluation for better coupling with risk evaluation methods. Overall this research provides evidence of (a) the conceptual integration of risk and sustainability discourses under one decision support framework for the case of WS-WR situations; (b) the use of a system thinking approach for interpreting the WS-WR situation; (c) the relevance of indicators as a means of representing the situation; (d) the interlinkage of social, economic, environmental information; (e) the benefits of the use of conceptual maps; (f) gaps in the process of measuring the effect of water reuse on water scarcity levels via indicators; (g) the gap between a simulation-based risk assessment and a snapshot-focused sustainability assessment that hinders an operational integration; (h) the possibility of the RSA framework to bridge a system thinking view with a traditional assessment-based decision-making view.:Acknowledgements Abstract Contents List of Figures List of Tables Acronyms and Abbreviations Symbols Chapter 1 - Introduction 1.1 Background and problem statement 1.1.1 Water resources for water security 1.1.2 Risk and sustainability discourses for water-related decision-making 1.1.3 Problem statement and research focus 1.2 Objectives and research questions 1.3 Research approach and structure of the document 1.3.1 Research approach 1.3.2 Structure of the document 1.4 Chapter references Chapter 2 - Conceptual Framework 2.1 Introduction 2.2 Developing the conceptual framework 2.2.1 Definition and interpretation of the subject at stake 2.2.2 Identification and definition of key concepts 2.2.3 Construction of the conceptual framework 2.3 Results and discussion 2.3.1 Defining and interpreting the ‘water scarcity – water reuse’ situation 2.3.2 Identifying and defining key concepts 2.3.3 Construction of the integrated RSA Framework 2.4 Conclusions and outlook 2.5 Acknowledgements 2.6 Chapter references Chapter 3 - Methodological Aspects 3.1 Introduction 3.2 RSA Framework for a WS-WR situation 3.3 Systems thinking in a WS-WR situation 3.3.1 Identifying elements of a WS-WR situation and its interpretation as a system 3.3.2 Translation of the CHANS into an information system 3.4 Characterisation and interlinkage of indicators 3.4.1 Type and number of indicators 3.4.2 Type and number of interlinkages 3.4.3 Indicator connectivity 3.4.4 Structuring via a lane-based approach 3.5 RSA analytical concept and exemplification 3.5.1 RSA analytical concept 3.5.2 Exemplification of the analyitical concept 3.6 Discussion 3.6.1 Translating the CHANS into an information system 3.6.2 Supporting decision-making via the analytical concept 3.7 Conclusions 3.8 Acknowledgements 3.9 Chapter references Chapter 4 - Framework Testing 4.1 Introduction 4.2 Approach 4.2.1 RSA Framework 4.2.2 Case study site 4.3 Results 4.3.1 Analysis 4.3.2 Evaluation 4.3.3 General results for the case 4.4 Discussion 4.4.1 Analysis 4.4.2 Evaluation 4.4.3 Overall discussion on the testing of the RSA Framework 4.5 Conclusions 4.6 Acknowledgements 4.7 Chapter References Chapter 5 - Synthesis 5.1 Conceptual aspects 5.2 Methodological aspects 5.3 Testing aspects 5.4 Placing the RSA Framework in a broader context 5.5 Chapter References Chapter 6 - Conclusions and Outlook Annexes Annex A - Literature review: Found records Annex B - Example list of endpoints, descriptors, indicators, and attributes Annex C - Technique for Order Preference by Similarly to Ideal Solution (TOPSIS) Annex D - Translation into the Information System (from endpoints to attributes) Annex E - Interlinkages Identification Matrix Annex F - List of Most Interlinked Indicators (MII) Annex G - List of indicators, scores, and threshold

    Decision Support Tools for Urban Water and Wastewater Systems –Focussing on Hazardous Flows Assessment

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    Abstract The Swedish research programme Urban Water has developed a concept of a multi-criteria basis intended to support decision-making for urban water and wastewater systems. Five criteria groups were established for sustainability assessment of urban water systems: Health and Hygiene, Environment, Economy, Socio-culture, and Technology. Each criterion requires a set of indicators corresponding to quantifiable facts and figures, or qualitative data to comparatively assess the different alternatives in the decision process. The decision support process starts as a baseline study where the existing conditions are addressed. Alternative strategies of the future urban water system are developed and analysed by different tools and methodologies in assessing the five criteria groups. Eventually, the results and conclusions are integrated and synthesised into a basis for decision-making. As an example of a decision support basis for chemical safety, a barrier perspective was introduced to find out if and to what extent hazardous substances can be stopped, diverged, or transformed at various points in the wastewater system. A set of barriers was suggested, i.e. behaviour, systems design, process design, optional recipients, and organisational. The barrier approach was applied to two alternative municipal wastewater system designs -a combined wastewater system vs. a source separated system -analysing the fate of phosphorus, cadmium, and triclosan. The study showed that the combined system caused a higher substance flow to the receiving waterbody than the separated system. The combined system also brought more phosphorus and cadmium to the farmland than the separated system, but only half the amount of triclosan

    Development of Bridge Information Model (BrIM) for digital twinning and management using TLS technology

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    In the current modern era of information and technology, the concept of Building Information Model (BIM), has made revolutionary changes in different aspects of engineering design, construction, and management of infrastructure assets, especially bridges. In the field of bridge engineering, Bridge Information Model (BrIM), as a specific form of BIM, includes digital twining of the physical asset associated with geometrical inspections and non-geometrical data, which has eliminated the use of traditional paper-based documentation and hand-written reports, enabling professionals and managers to operate more efficiently and effectively. However, concerns remain about the quality of the acquired inspection data and utilizing BrIM information for remedial decisions in a reliable Bridge Management System (BMS) which are still reliant on the knowledge and experience of the involved inspectors, or asset manager, and are susceptible to a certain degree of subjectivity. Therefore, this research study aims not only to introduce the valuable benefits of Terrestrial Laser Scanning (TLS) as a precise, rapid, and qualitative inspection method, but also to serve a novel sliced-based approach for bridge geometric Computer-Aided Design (CAD) model extraction using TLS-based point cloud, and to contribute to BrIM development. Moreover, this study presents a comprehensive methodology for incorporating generated BrIM in a redeveloped element-based condition assessment model while integrating a Decision Support System (DSS) to propose an innovative BMS. This methodology was further implemented in a designed software plugin and validated by a real case study on the Werrington Bridge, a cable-stayed bridge in New South Wales, Australia. The finding of this research confirms the reliability of the TLS-derived 3D model in terms of quality of acquired data and accuracy of the proposed novel slice-based method, as well as BrIM implementation, and integration of the proposed BMS into the developed BrIM. Furthermore, the results of this study showed that the proposed integrated model addresses the subjective nature of decision-making by conducting a risk assessment and utilising structured decision-making tools for priority ranking of remedial actions. The findings demonstrated acceptable agreement in utilizing the proposed BMS for priority ranking of structural elements that require more attention, as well as efficient optimisation of remedial actions to preserve bridge health and safety

    An Integrated Gate Turnaround Management Concept Leveraging Big Data Analytics for NAS Performance Improvements

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    "Gate Turnaround" plays a key role in the National Air Space (NAS) gate-to-gate performance by receiving aircraft when they reach their destination airport, and delivering aircraft into the NAS upon departing from the gate and subsequent takeoff. The time spent at the gate in meeting the planned departure time is influenced by many factors and often with considerable uncertainties. Uncertainties such as weather, early or late arrivals, disembarking and boarding passengers, unloading/reloading cargo, aircraft logistics/maintenance services and ground handling, traffic in ramp and movement areas for taxi-in and taxi-out, and departure queue management for takeoff are likely encountered on the daily basis. The Integrated Gate Turnaround Management (IGTM) concept is leveraging relevant historical data to support optimization of the gate operations, which include arrival, at the gate, departure based on constraints (e.g., available gates at the arrival, ground crew and equipment for the gate turnaround, and over capacity demand upon departure), and collaborative decision-making. The IGTM concept provides effective information services and decision tools to the stakeholders, such as airline dispatchers, gate agents, airport operators, ramp controllers, and air traffic control (ATC) traffic managers and ground controllers to mitigate uncertainties arising from both nominal and off-nominal airport gate operations. IGTM will provide NAS stakeholders customized decision making tools through a User Interface (UI) by leveraging historical data (Big Data), net-enabled Air Traffic Management (ATM) live data, and analytics according to dependencies among NAS parameters for the stakeholders to manage and optimize the NAS performance in the gate turnaround domain. The application will give stakeholders predictable results based on the past and current NAS performance according to selected decision trees through the UI. The predictable results are generated based on analysis of the unique airport attributes (e.g., runway, taxiway, terminal, and gate configurations and tenants), and combined statistics from past data and live data based on a specific set of ATM concept-of-operations (ConOps) and operational parameters via systems analysis using an analytic network learning model. The IGTM tool will then bound the uncertainties that arise from nominal and off-nominal operational conditions with direct assessment of the gate turnaround status and the impact of a certain operational decision on the NAS performance, and provide a set of recommended actions to optimize the NAS performance by allowing stakeholders to take mitigation actions to reduce uncertainty and time deviation of planned operational events. An IGTM prototype was developed at NASA Ames Simulation Laboratories (SimLabs) to demonstrate the benefits and applicability of the concept. A data network, using the System Wide Information Management (SWIM)-like messaging application using the ActiveMQ message service, was connected to the simulated data warehouse, scheduled flight plans, a fast-time airport simulator, and a graphic UI. A fast-time simulation was integrated with the data warehouse or Big Data/Analytics (BAI), scheduled flight plans from Aeronautical Operational Control AOC, IGTM Controller, and a UI via a SWIM-like data messaging network using the ActiveMQ message service, illustrated in Figure 1, to demonstrate selected use-cases showing the benefits of the IGTM concept on the NAS performance

    Swedish LifeWatch ─ a biodiversity infrastructure integrating and reusing data from citizen science, monitoring and research

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    With continued pressure on biodiversity and ever-growing conflicts with human development, qualified systems for scenario modelling, impact assessment and decision support are urgently needed. Such systems must be able to integrate complex models and information from many sources and do so in a flexible and transparent way. To that end, as well as for other complicated and data-intensive biodiversity research purposes, the concept of LifeWatch has emerged. The idea of LifeWatch is to construct e-infrastructure and virtual laboratories by integrating large data sources, computational capacities, and tools for analysis and modelling in an open, serviceoriented architecture. To be efficient and accurate, a continuous inflow of large quantities of data is essential. However, even with new techniques, government-funded monitoring data and research data will not feed the system with up-to-date species information of sufficient scale and resolution. To fill this void, skilled amateur observers (citizen scientists) can contribute to a very valuable extent. After a preparatory phase, a Swedish LifeWatch (SLW) consortium was initiated in 2011. Swedish LifeWatch developed an infrastructure where all components are accessible through open web services. At the SLW Analysis portal, different formats of species and environmental data can be accessed instantly, and integrated, analysed, visualized and downloaded at selected temporal, spatial or taxonomic scales. Swedish LifeWatch currently provides 46 million species observations from eight different databases, all harmonized according to standardized formats and the Dyntaxa taxonomic backbone database. Almost 40 million of these observations were provided by citizens through the online reporting system named the Species Observation System (SOS) or Artportalen. This paper describes this system, as well as the incentives that make it so successful. The citizen science data in the SOS are accessible, together with data from research and monitoring, in the SLW infrastructure, making the latter a powerful instrument for large-scale data extraction, visualization and analysis

    The Integrated Realization of Materials, Products and Associated Manufacturing Processes

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    Problem: A materials design revolution is underway in the recent past where the focus is to design (not select) the material microstructure and processing paths to achieve multiple property or performance requirements that are often in conflict. The advancements in computer simulations have resulted in the speeding up of the process of discovering new materials and has paved way for rapid assessment of process-structure-property-performance relationships of materials, products, and processes. This has led to the simulation-based design of material microstructure (microstructure-mediated design) to satisfy multiple property or performance goals of the product/process/system thereby replacing the classical material design and selection approaches. The foundational premise for this dissertation is that systems-based materials design techniques offer the potential for tailoring materials, their processing paths and the end products that employ these materials in an integrated fashion for challenging applications to satisfy conflicting product and process level property and performance requirements. The primary goal in this dissertation is to establish some of the scientific foundations and tools that are needed for the integrated realization of materials, products and manufacturing processes using simulation models that are typically incomplete, inaccurate and not of equal fidelity by managing the uncertainty associated. Accordingly, the interest in this dissertation lies in establishing a systems-based design architecture that includes system-level synthesis methods and tools that are required for the integrated design of complex materials, products and associated manufacturing processes starting from the end requirements. Hence the primary research question: What are the theoretical, mathematical and computational foundations needed for establishing a comprehensive systems-based design architecture to realize the integrated design of the product, its environment, manufacturing processes and material as a system? Major challenges to be addressed here are: a) integration of models (material, process and product) to establish processing-structure-property-performance relationships, b) goal-oriented inverse design of material microstructures and processing paths to meet multiple conflicting performance/property requirements, c) robust concept exploration by managing uncertainty across process chains and d) systematic, domain-independent, modular, reconfigurable, reusable, computer interpretable, archivable, and multi-objective decision support in the early stages of design to different users. Approach: In order to address these challenges, the primary hypothesis in this dissertation is to establish the theoretical, mathematical and computational foundations for: 1) forward material, product and process workflows through systematic identification and integration of models to define the processing-structure-property-performance relationships; 2) a concept exploration framework supporting systematic formulation of design problems facilitating robust design exploration by bringing together robust design principles and multi-objective decision making protocols; 3) a generic, goal-oriented, inverse decision-based design method that uses 1) and 2) to facilitate the systems-based inverse design of material microstructures and processing paths to meet multiple product level performance/property requirements, thereby generating the problem-specific inverse decision workflow; and 4) integrating the workflows with a knowledge-based platform anchored in modeling decision-related knowledge facilitating capture, execution and reuse of the knowledge associated with 1), 2) and 3). This establishes a comprehensive systems-based design architecture to realize the integrated design of the product, its environment, manufacturing processes and material as a system. Validation: The systems-based design architecture for the integrated realization of materials, products and associated manufacturing processes is validated using the validation-square approach that consists of theoretical and empirical validation. Empirical validation of the design architecture is carried out using an industry driven problem namely the ‘Integrated Design of Steel (Material), Manufacturing Processes (Rolling and Cooling) and Hot Rolled Rods (Product) for Automotive Gears’. Specific sub-problems are formulated within this problem domain to address various research questions identified in this dissertation. Contributions: The contributions from the dissertation are categorized into new knowledge in four research domains: a) systematic model integration (vertical and horizontal) for integrated material and product workflows, b) goal-oriented, inverse decision support, c) robust concept exploration of process chains with multiple conflicting goals and d) knowledge-based decision support for rapid and robust design exploration in simulation-based integrated material, product and process design. The creation of new knowledge in this dissertation is associated with the development of a systems-based design architecture involving systematic function-based approach of formulating forward material workflows, a concept exploration framework for systematic design exploration, an inverse decision-based design method, and robust design metrics, all integrated with a knowledge-based platform for decision support. The theoretical, mathematical and computational foundations for the design architecture are proposed in this dissertation to facilitate rapid and robust exploration of the design and solution spaces to identify material microstructures and processing paths that satisfy conflicting property and performance for complex materials, products and processes by managing uncertainty

    Multi-agent knowledge integration mechanism using particle swarm optimization

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    This is the post-print version of the final paper published in Technological Forecasting and Social Change. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V.Unstructured group decision-making is burdened with several central difficulties: unifying the knowledge of multiple experts in an unbiased manner and computational inefficiencies. In addition, a proper means of storing such unified knowledge for later use has not yet been established. Storage difficulties stem from of the integration of the logic underlying multiple experts' decision-making processes and the structured quantification of the impact of each opinion on the final product. To address these difficulties, this paper proposes a novel approach called the multiple agent-based knowledge integration mechanism (MAKIM), in which a fuzzy cognitive map (FCM) is used as a knowledge representation and storage vehicle. In this approach, we use particle swarm optimization (PSO) to adjust causal relationships and causality coefficients from the perspective of global optimization. Once an optimized FCM is constructed an agent based model (ABM) is applied to the inference of the FCM to solve real world problem. The final aggregate knowledge is stored in FCM form and is used to produce proper inference results for other target problems. To test the validity of our approach, we applied MAKIM to a real-world group decision-making problem, an IT project risk assessment, and found MAKIM to be statistically robust.Ministry of Education, Science and Technology (Korea
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