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Public transport plays a prominent role with respect to mitigating transport-related environmental effects by improving passenger transport efficiency and the quality of life in cities. Batteries and fuel cells are at the forefront of the technological shift to zero-emission powertrains. Within the scope of the German-funded project BIC H2, corresponding systems analysis research focuses on the market introduction of fuel cell–electric buses in the Rhine–Ruhr Metropolitan Region through 2035. This study presents the related methods and major outcomes of this techno-economic research, which spans spatially-resolved hydrogen demand modeling of all relevant sectors, to hydrogen refueling stations and upstream infrastructure modeling, to scenario-based analyses. The latter builds upon an empirical study supporting the development of the Hydrogen Roadmap of the State of North Rhine–Westphalia (NRW). Our results show that the demand in NRW alone is expected to account for one third of total German hydrogen use. Hydrogen bus refueling could substantially support market introduction during its early phases. In the long term, however, hydrogen demand in industry is significantly higher compared to that in the transport sector. Furthermore, spatial analysis identifies regions with pronounced hydrogen demands that could, therefore, be candidates for initial infrastructure investments. With the Cologne area showing the highest hydrogen demand levels, such regions can offer particularly high infrastructure utilization, e.g., for bus refueling. On the infrastructure side, trailers for transporting gaseous hydrogen to refueling stations are the most favorable option through 2035. Pipelines would be the preferred solution soon after 2035 due to increased hydrogen demand. If effectively deployed, converted natural gas pipelines would be the most cost-effective option even earlier. • Project-accompanying research related to fuel cell bus refueling infrastructure. • H 2 market introduction in Germany's Rhine–Ruhr Metropolitan Region through 2035. • Spatially-resolved H 2 demand & infrastructure modeling and scenario-based analyses. • Aligned with road map for the state of North Rhine-Westphalia. • Identifies regions with pronounced H2 demand, such as the Cologne area. [ABSTRACT FROM AUTHOR]

Large scale, low cost, and low carbon intensity hydrogen production is needed to reduce emissions in the energy and transportation sectors. We present a techno-economic analysis and life cycle assessment of natural gas pyrolysis technologies for hydrogen production, with carbon black (CB) as a co-product. Four designs were considered based on the source of heat to the pyrolysis system, the combustion medium, and use of carbon capture (CC) technology. The oxygen-fired-CB design with CC is the most attractive from financial and environmental perspectives, superior to a conventional steam methane reformer (SMR) process with CC. The estimated pre-tax minimum hydrogen selling prices for the pyrolysis technologies range between $1.08/kg and $2.43/kg when natural gas (NG) costs $3.76/GJ. Key advantages include near-zero onsite GHG emissions of the oxygen-fired-CB design with CC and up to 41% lower GHG emissions compared to the SMR + CC process. The results indicate that natural gas pyrolysis may be a feasible pathway for hydrogen production. • Commercial scale hydrogen production via natural gas pyrolysis pathways is explored. • Options for handling the carbon black product are examined. • Low-carbon hydrogen of $1.7/kgH 2 outperforms the SMR hydrogen at similar conditions. • Cradle to gate GHG emissions between 1.8 and 4.6 kgCO 2 eq/kgH 2 is computed. [ABSTRACT FROM AUTHOR]

Operating room (OR) efficiency has an impact on surgeon productivity and patient experience. Accuracy of case duration estimation is important to optimize OR efficiency. The purpose of this study was to identify factors associated with inaccurate case time estimates in outpatient hand surgery. A better understanding of these findings may help to improve OR efficiency and scheduling. All outpatient hand surgical cases from 2018 to 2019 were reviewed. Poorly-estimated cases (i.e., poor scheduling accuracy) were defined as those cases where the actual operative time differed from the predicted time by >50% (either quicker by >50% or slower by >50% than the predicted time). The percentages of poorly-estimated cases were analyzed, categorized, and compared by surgeon, procedure type, and scheduled case length. A total of 6,620 cases were identified. Of 1,107 (16.7%) cases with poorly estimated case durations, 75.2% were underestimated. There was no difference in the likelihood of poor estimation related to start time. Well-estimated cases tended to have longer scheduled case duration, but shorter realized case duration and surgical time. Our systems analysis identified specific surgeons and procedures as predictable outliers. Cases scheduled for 15–30 minutes frequently were inaccurate, whereas cases scheduled for 30–45 and 106–120 minutes had accurate estimates. The accuracy of case time estimations in a standard outpatient hand surgery practice is highly variable. Nearly one-fifth of outpatient hand surgery case durations are poorly estimated, and inaccurate case time estimation can be predicted based on surgeon, procedure type, and case time. Maximizing OR efficiency should be a priority for surgeons and hospital systems. With multiple surgeries done per day, the efficiency of the OR has an impact on surgeon productivity and patient experience. [ABSTRACT FROM AUTHOR]

Sudden cardiac arrest affects around half a million people aged under 50 years old annually, with a 90% mortality rate. Despite high patient numbers and clear clinical need to improve outcomes, many gaps exist in the evidence underpinning patients' management. Domains identifying the greatest barriers to conducting trials are the prehospital and forensic settings, which also provide care to the majority of patients. Addressing gaps in evidence along each point of the cardiac arrest trajectory is a key clinical priority. [ABSTRACT FROM AUTHOR]

The systems analysis framework has permeated the social and political sciences, and its use is increasing in the analysis of global value chains. Nevertheless, minimal research has applied this systems analysis to investigate voluntary sustainability standards (VSS) in the value chain. This study employs systems analysis to explore the role and interactions of VSS in the coffee value chains of Costa Rica and Colombia. Using discourse analysis, the study identifies in the discourses of interviewed stakeholders system traps (this means specific archetypes systems tend to evolve when not balanced) and leverage points that can initiate rapid and significant changes in complex systems when introduced. The interviewed stakeholders cited numerous examples of events related to the identified traps and leverage points in the value chains examined. Another relevant finding is the coherence of these discourses, which were consistent and had no contradictions in different stakeholders' expressions. The findings contribute to the research regarding private governance in the agricultural sector, introducing a new analytical framework. [ABSTRACT FROM AUTHOR]

• Parametric analysis of PVT+GSHP borehole field sizing and system controls. • PVT+GSHP can save up to 89% of land needed for boreholes over GSHP. • Given adequate land, PV+GSHP systems are more cost effective than PVT+GSHP systems. • A multi-dimensional sensitivity analysis is made on critical economic parameters. • PVT can help expand the GSHP market in land-restricted, multi-family homes. The electrification of buildings is a promising pathway to the decarbonization of cities. This is a parametric study of the technical and economic performance of ground source heat pump (GSHP) systems with series connected solar PV/thermal (PVT) collectors. The focus is on multi-family houses (MFH) in the heating dominated climate of Sweden, where land restrictions for boreholes or noise restrictions on air heat exchangers limit the heat pump market. System efficiency and lifecycle cost results are generated using a holistic and detailed systems model in TRNSYS with 20 year simulations. The results show that PVT can reduce borehole length by 18% or spacing by 50% while maintaining an equivalent seasonal performance factor to systems without PVT. The cost for PVT+GSHP systems is higher than a traditionally designed PV+GSHP, however this does not take into account the value of the land area saved by PVT, which can be up to 89%. The reduction in land enabled by PVT has the potential to increase penetration of GSHP in MFH and promote solar energy diffusion in high latitude markets. [ABSTRACT FROM AUTHOR]

Abstract Current practices to identify, organize, analyze, and serve data to water resources systems models are typically model and dataset-specific. Data are stored in different formats, described with different vocabularies, and require manual, model-specific, and time-intensive manipulations to find, organize, compare, and then serve to models. This paper presents the Water Management Data Model (WaMDaM) implemented in a relational database. WaMDaM uses contextual metadata, controlled vocabularies, and supporting software tools to organize and store water management data from multiple sources and models and allow users to more easily interact with its database. Five use cases use thirteen datasets and models focused in the Bear River Watershed, United States to show how a user can identify, compare, and choose from multiple types of data, networks, and scenario elements then serve data to models. The database design is flexible and scalable to accommodate new datasets, models, and associated components, attributes, scenarios, and metadata. Graphical abstract Image 1 Highlights • We present a data model to organize water resources systems data and models. • Controlled vocabularies link native terms across different datasets and models. • Software tools manage controlled vocabularies and help load datasets. • Modelers can identify and compare available data then serve data to models. [ABSTRACT FROM AUTHOR]

Highlights • Port infrastructure and port operations are highly impacted by disruptive scenarios. • Examining the joint influences of scenarios and stakeholders to priorities. • The most disruptive scenario to the stakeholders is the traffic congestion. • The least disruptive scenario is the high operation cost. • The most robust and highly prioritized initiative is constructing the CIMT terminal. Abstract Port infrastructure and port operations are highly impacted by disruptive scenarios that stem from several different types of causes, including adverse weather events, economic crises, traffic congestion, and spikes in demand, among others. Port intermodal transportation systems are characterized by high complexity and uncertainty since they serve and impact multiple groups of stakeholders, including exporters, importers, operators, organizations, port workers, port authorities, residents, and others. The influences of the disruptive scenarios combined with the influences of possible conflicting interests among groups of stakeholders make significant impacts to port operations and planning programs. The innovation of this study is that it integrates two existing approaches to resilience analytics addressing the influences of scenarios and stakeholders to priorities: a stakeholder classification approach called stakeholder mapping , and an approach known as scenario-based preferences modeling. The framework that is developed in this paper finds the joint influences of disruptive scenarios and groups of stakeholders to disrupt the importance ranking of initiatives. The results emphasize that the most disruptive scenario to the multiple groups of stakeholders is s 1 , Traffic Congestion , the least disruptive scenario is s 3 , High Operation Cost , and the most robust and highly prioritized initiative is x 18 , Constructing the CIMT marine terminal. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET #1) and polyolefin plastics such polyethylene (HDPE #2, LDPE #4) and polypropylene (PP #5) are major products from the chemical industry, and they comprise a significant fraction of municipal solid waste that ends up in landfills or as litter and marine debris. The reuse of these polymeric materials can be optimized through systems analysis with a view on materials flow analysis, techno-economics, environmental life cycle assessment, and consequential societal impacts. This contribution will present the overall research approach for this exploratory project within the DOE- and industry-funded REMADE Institute and end with a proposed systems analysis framework. [ABSTRACT FROM AUTHOR]

• Wide range of performance parameters were scanned for the optimal design space of a compact tokamak fusion reactor. • Novel computational algorithm to determine the optimum radial build was utilized. • Prospective design space was determined depending on the levels of physics and technology. Using a novel computational algorithm that integrates tokamak systems analysis with neutron transport calculations, the minimum major radius (R 0) and resulting maximum magnetic field at the plasma center (B T) can be determined uniquely for a given plasma performance. Plasma performance was varied extensively using a supercomputer (KAIROS) and scanning over a wide range of physics, technology, and system parameters to derive the optimal design space for a compact tokamak fusion reactor. Given the design goals of fusion gain Q > 20.0, net electric power > 100 MW, neutron wall loading < 2.0 MW/m2, indicator of divertor power handling P SOL / R 0 < 25 MW/m, direct capital cost < $4.0 billion, and steady-state operation, a prospective design space was determined depending on the levels of physics and technology. Advanced engineering features, such as maximum allowable magnetic field at the toroidal field coil (B max = 23 T), were implemented by adopting high-temperature superconducting magnet technology, using an advanced shield material such as tungsten carbide (WC), and a plug-bucked magnet support structure. It was found that by exceeding the energy confinement scaling laws of IPB98y2, a design space of R 0 < 4.0 m could be accessed under the following conditions for a conventional tokamak: confinement enhancement factor H > 1.7, bootstrap current fraction f BS > 0.55, magnetic field at the magnetic axis B T > 4.0 T, fusion power P fusion > 600 MW, and thermodynamic efficiency η th > 0.33. For a spherical tokamak, these conditions were H > 1.3, f BS > 0.6, B T 〈 6.0 T, and P fusion 〉 500 MW. Sensitivity studies on the energy confinement scaling laws showed that stricter conditions on the physics parameters were required with the ITPA20 scaling law, whereas the conditions were mitigated with the β-independent scaling law. [ABSTRACT FROM AUTHOR]

The aim of this work was to find the optimal resource-efficient treatment alternative for organic waste from the food industry. For that, four different treatment methods for thirteen feedstocks were studied: animal fodder production, incineration, biological treatment and biogas production. An optimization model was used to find which treatment alternative is the optimal from a variety of perspectives. The studied systems were evaluated from three different evaluation perspectives: economy, energy and environment. The energy evaluation included two different electricity systems: coal condensing power and wind energy. The results show that there is no single optimum feedstock treatment method taking all the perspectives studied into account. Instead, it is important to consider all different perspectives when evaluating the resource efficiency of the treatment method for a feedstock. However, both incineration and anaerobic digestion of the food waste can be considered as resource-efficient treatment options for the studied feedstocks. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Among biomass energy technologies which are treated as the promising way to mitigate critical energy crisis and global climate change, biomass gasification plays a key role given to its gaseous fuels especially syngas for distributed power plant. However, a system analysis for the energy saving and greenhouse gas emissions abatement potentials of gasification system has been directed few attentions. This study presents a system analysis that combines process and input-output analyses of GHG emissions and energy costs throughout the full chain of activities associated with biomass gasification. Incorporating agricultural production, industrial process and wastewater treatment which is always ignored, the energy inputs in life cycle are accounted for the first commercial biomass gasification power plant in China. Results show that the non-renewable energy cost and GHG emission intensity of the biomass gasification system are 0.163 MJ/MJ and 0.137 kg CO 2 -eq/MJ respectively, which reaffirm its advantages over coal-fired power plants in clean energy and environmental terms. Compared with other biomass energy processes, gasification performs well as its non-renewable energy cost and CO 2 intensity are in the central ranges of those for all of these technologies. Construction of the plant is an important factor in the process's non-renewable energy consumption, contributing about 44.48% of total energy use. Wastewater treatment is the main contributor to GHG emissions. The biomass gasification and associated wastewater treatment technologies have critical influence on the sustainability and renewability of biomass gasification. The results provide comprehensive analysis for biomass gasification performance and technology improvement potential in regulating biomass development policies for aiming to achieve sustainability globally. Highlights • Embodied nonrenewable energy consumption and GHG emissions are explored. • Biogas-electricity is more environment friendly than that from coal. • Water treatment inducing major GHG emissions should be considered. • Reducing nonrenewable energy in construction phase is necessary. [ABSTRACT FROM AUTHOR]

Abstract Investigating protein-protein interactions and protein phosphorylation can be of great significance when studying biological processes and human diseases at the molecular level. However, sample complexity, presence of low abundance proteins, and dynamic nature of the proteins often impede in achieving sufficient analytical depth in proteomics research. In this regard, chromatographic separation methodologies have played a vital role in the identification and quantification of proteins in complex sample mixtures. The combination of peptide and protein fractionation techniques with advanced high-performance mass spectrometry has allowed the researchers to successfully study the protein-protein interactions and protein phosphorylation. Several new fractionation strategies for large scale analysis of proteins and peptides have been developed to study protein-protein interactions and protein phosphorylation. These emerging chromatography methodologies have enabled the identification of several hundred protein complexes and even thousands of phosphorylation sites in a single study. In this review, we focus on current workflow strategies and chromatographic tools, highlighting their advantages and disadvantages, and examining their associated challenges and future potential. Highlights • Combinatorial chromatography effectively separates proteins/peptides for MS analysis. • Fractionation strategies enable PPI and protein phosphorylation studies. • New workflow strategies enhance detection of low abundance proteins and peptides. • Chromatographic fractionation methods give rise to future analytical possibilities. [ABSTRACT FROM AUTHOR]

Abstract The recovery of uranium from seawater has the potential to transform the perceived sustainability of energy generated by uranium intensive nuclear fuel cycles, while providing environmental benefits as compared to land-based mining. Combining a seawater uranium harvester with an existing offshore wind turbine allows for denser energy recovery per unit ecosystem, as well as lowering the uranium production cost. The analysis presented in this paper focuses on the economic impacts on uranium recovered by adsorbing material deployed with such a symbiotic system as compared to a reference kelp-field like deployment. The Wind and Uranium from Seawater Acquisition symBiotic Infrastructure (WUSABI) was subjected to an independent economic analysis and design optimizations in an effort to reduce the seawater uranium cost. In addition to providing greater transparency to previous economic analyses of this system, this work alters chemical tank materials and establishes a novel means of calculating and optimizing the interval in which symbiotic systems are serviced. The perturbations proposed in this work could achieve a cost savings of 30% as compared to uranium produced from the reference kelp-field like deployment system. Additional design sensitivities are also explored to identify major cost drivers and guide future work regarding deployment location of the turbine field. Highlights • The cost-analysis of a symbiotic system to harvest seawater uranium is conducted. • Chemical tank materials are altered to more cost-effective substitutes. • A method to optimize the servicing interval of symbiotic systems is presented. • Perturbations proposed in this work could achieve a cost savings of 30%. • Major cost drivers are identified through exploring design sensitivities. [ABSTRACT FROM AUTHOR]

Abstract Cross-impact methods are planning, foresight and decision support tools often used in conjunction with the scenario technique. They enable systems modeling in a theory-driven way, grounded in expert judgment and understanding. This article presents the EXIT approach, a novel modeling technique and a computational method for structural cross-impact analysis. EXIT extracts insights from an expert-sourced cross-impact model, which describes the structure of direct interactions within a system. The EXIT transformation produces a relative quantification of the emergent, systemic relationships between model components, effectuating over the complex web of interactions in the system. Compared to the more established matrix multiplication approach, EXIT produces novel and more detailed analytical outputs on the basis of similar input, and offers new analytical possibilities in structural cross-impact analysis. A software implementing the EXIT transformation is freely available. Highlights • EXIT is a novel approach for cross-impact modeling and analysis. • EXIT models are based on expert-sourced data of the direct interactions in a system. • EXIT can be used for structural analysis of many socio-techno-economic systems. • The output is information about the higher-order interactions in the system. • EXIT offers new analytical capabilities compared to existing approaches. [ABSTRACT FROM AUTHOR]

The need to consider environmental and social issues on a par with economic concerns in policy, plan, programme and project making in order to achieve sustainable development has been widely recognized. However, to date there has been no adequate implementation, and economic issues are frequently prevailing over other aspects. In many developing and emerging economies, a perceived urgency to promote economic growth frequently means that environmental and social costs of development are overlooked. It is within this context that this paper explores the consideration of environmental and social issues in transport policy, plan and programme (PPP) making in Brazil, an emerging economy which over recent years has invested heavily in its transport infrastructure. Aiming at establishing the extent to which environmental and social issues are considered and identifying the barriers for better practice, legal and institutional frameworks for transport PPP making, the substantive focus of PPPs as well as perceptions of actors involved in their preparation are investigated. Results show that whilst the need to respect environmental and social issues is recognized in sectoral guidelines and underlying values, in practice they are poorly considered. Main constraints to a better consideration of sustainable development in transport PPP making include the lack of instruments for a systematic consideration, the nature of existing PPP making processes and the dominance of political and economic interests. Moreover, suggestions for improvement are limited and mainly relate to external pressures. In this context, Strategic Environmental Assessment in particular would need to be introduced as an instrument for a more rigorous and clearly prescribed consideration of environmental and social issues. [ABSTRACT FROM AUTHOR]

High pressure enriched oxygen is used in a wide number of areas, including aircraft, medical breathing apparatus, and a number of industrial processes including combustion. Unwanted ignition in such systems can cause significant damage to property and danger to life. It is important to gain as much information, and record relevant data for every oxygen incident, enabling both immediate analysis, and post-event evaluations (especially where circumstances are repeated). The lack of clear concise guidance can result in data loss. This work successfully develops investigation 'road maps' as guidance documents for investigators to use, even under difficult & time pressured conditions. The work demonstrates their usefulness and importance for information collection and the down-selection' or elimination of possible ignition causes through their use with a 'real world' case study. The benefit of this work will be to enable faster and more effective investigation of oxygen incidents, ensuring key details are recorded (benefitting post-accident academic data & meta-study analysis). The roadmaps can also benefit designers of oxygen systems allowing them to test their designs and operating procedures against specific ignition scenarios. [ABSTRACT FROM AUTHOR]

Objective To identify factors contributing to the development of anaesthetic safety incidents. Study design Prospective, descriptive, voluntary reporting audit of safety incidents with subsequent systems analysis. Animals All animals anaesthetized in a multispecies veterinary teaching hospital from November 2014 to October 2016. Methods Peri-anaesthetic incidents that risked or caused unnecessary harm to an animal were reported by anaesthetists alongside animal morbidity and mortality data. A modified systems analysis framework was used to identify contributing factors from the following categories: Animal and Owner, Task and Technology, Individual, Team, Work Environmental, and Organizational and Management. The outcome was graded using a simple descriptive scale. Data were analysed using Pearson's Chi-Square test for association and univariable and multivariable logistic regression analysis. Results Totally, 3379 anaesthetics were performed during the audit period. Of these, 174 incident reports were analysed, 163 of which impacted safe veterinary care and 26 incidents were considered to have had major or catastrophic outcomes. Incident outcome was believed to have been limited by anaesthetist intervention in 104 (63.8%) cases. Various factors were identified as: Individual in 123 (70.7%), Team in 108 (62.1%), Organizational and Management in 94 (54.0%), Task and Technology in 80 (46.0%), Work Environmental in 53 (30.5%) and Animal and Owner in 36 (20.7%) incidents. Individual factors were rarely seen in isolation. Significant associations were identified between Experience and Supervision, X2 (1, n =174) = 54177, p= 0.001, Failure to follow a standard operating procedure and Task Management, 2 (2, n =174) =11318, p= 0.001, and Staffing and Poor Scheduling, X2 (1, n =174) = 36742, p= 0.001. Animal Condition [odds ratio (OR) = 16210, 95% confidence interval (CI) = 5573e47147)] and anaesthetist Decision Making (OR =3437, 95% CI =1184e9974) were risk factors for catastrophic and major outcomes. Conclusions and clinical relevance Individual factors contribute to many safety incidents but tend to occur concurrently with other factors. Anaesthetist intervention limits the consequences of incidents for most animals. [ABSTRACT FROM AUTHOR]

Integrated solar combined cycles (ISCCs) need to be able to handle some of the most dynamic operating conditions of any power generation system in order to provide the flexibility of a natural gas combustion turbine while simultaneously utilizing variable incident solar irradiation. Yet to date, most work on ISCC design has focused on high-level treatments of system viability and potential impact, without thorough consideration of system operations. In this work, a computationally efficient ISCC model is constructed that includes detailed modeling of the heat recovery steam generator that links the natural gas and solar thermal systems. The model is validated against a model in the literature, and then used to perform computational optimization of the facility operations. Critically, a wide variety of practical system constraints are considered at each time step evaluated in order to ensure system feasibility under realistic conditions. It is shown that under different operating modes the ISCC design examined displays similar emission rates, yet significantly different profit ranges. A marked increase in the operating flexibility of the ISCC is observed when the outlet temperature of the solar heat transfer fluid is allowed to vary over the course of the day. [ABSTRACT FROM AUTHOR]

Concentrating solar power towers, which include a steam-Rankine cycle with molten salt thermal energy storage, is an emerging technology whose maximum effectiveness relies on an optimal operational and dispatch policy. Given parameters such as start-up and shut-down penalties, expected electricity price profiles, solar availability, and system interoperability requirements, this paper seeks a profit-maximizing solution that determines start-up and shut-down times for the power cycle and solar receiver, and the times at which to dispatch stored and instantaneous quantities of energy over a 48-h horizon at hourly fidelity. The mixed-integer linear program (MIP) is subject to constraints including: (i) minimum and maximum rates of start-up and shut-down, (ii) energy balance, including energetic state of the system as a whole and its components, (iii) logical rules governing the operational modes of the power cycle and solar receiver, and (iv) operational consistency between time periods. The novelty in this work lies in the successful integration of a dispatch optimization model into a detailed techno-economic analysis tool, specifically, the National Renewable Energy Laboratory’s System Advisor Model (SAM). The MIP produces an optimized operating strategy, historically determined via a heuristic. Using several market electricity pricing profiles, we present comparative results for a system with and without dispatch optimization, indicating that dispatch optimization can improve plant profitability by 5–20% and thereby alter the economics of concentrating solar power technology. While we examine a molten salt power tower system, this analysis is equally applicable to the more mature concentrating solar parabolic trough system with thermal energy storage. [ABSTRACT FROM AUTHOR]

The aim of the study was to quantify the environmental impact of four alternative recycling methods of thermal residues generated within the case study area chosen. Overall, 90 combinations of 13 scenarios were included in the study and a sensitivity analysis was performed. The recycling methods that were assessed included forest fertilization and neutralization, landfill construction, road construction, and road stabilization. Other scenarios focused on the regional optimization, distribution of heavy metals under L/S ratio 10 L kg − 1 , and uncertainty related to the determination of heavy metals at levels that were lower than the analytical limits of quantification. The alternative scenarios were studied using a comparative life cycle assessment method with the system expansion. The results indicated the extent to which each recycling method was superior to landfilling within non-toxic impact categories, with the average reduction in the environmental impact being 10–30% when the residues were utilized for forest fertilization, road construction, and stabilization, and by 3–12% when the residues were utilized for landfill construction. The majority of the impact resulted from avoiding the need to landfill the residues since this could be achieved even at a zero substitution rate in the majority of the cases. In terms of the toxic impact categories, the use of the residues for road construction purposes had a more positive impact on the environment that the alternative uses, resulting in a reduced ecotoxicity potential and carcinogenic human toxicity potentials of 30% and 40% respectively, and an increase in non-carcinogenic human toxicity potential of only 4%. Most of the toxic impact was the result of Ba, V, Sb, Co, Cr, and Zn leaching. In addition, the study concluded that a lack of the leaching data below the limits of quantification was significant for the overall toxic results of the study. [ABSTRACT FROM AUTHOR]

Practitioners of cost-utility analysis know that their models omit several important factors that often affect real-world decisions about health care options. Furthermore, cost-utility analyses typically reflect only single perspectives (e.g., individual, business, and societal), further limiting the value for those with different perspectives (patients, providers, payers, producers, and planners—the 5Ps). We discuss how models based on multicriteria analyses, which look at problems from many perspectives, can fill this void. Each of the 5Ps can use multicriteria analyses in different ways to aid their decisions. Each perspective may lead to different value measures and outcomes, whereas no single-metric approach (such as cost-utility analysis) can satisfy all these stakeholders. All stakeholders have unique ways to measure value, even if assessing the same health intervention. We illustrate the benefits of this approach by comparing the value of five different hypothetical treatment choices for five hypothetical patients with cancer, each with different preference structures. Nine attributes describe each treatment option. We add a brief discussion regarding the use of these approaches in group-based decisions. We urge that methods to value health interventions embrace the multicriteria approaches that we discuss, because these approaches 1) increase transparency about the decision process, 2) allow flight simulator-type evaluation of alternative interventions before actual investment or deployment, 3) help focus efforts to improve data in an efficient manner, 4) at least in some cases help facilitate decision convergence among stakeholders with differing perspectives, and 5) help avoid potential cognitive errors known to impair intuitive judgments. [ABSTRACT FROM AUTHOR]

We apply causal loop diagrams (CLD) to picture how complex societal scenarios can be understood in terms of interdependent drivers and mechanisms between actors from the public and private sectors respectively. And we show how un-sustainable scenarios can be understood in terms of insufficient balancing feed-back in the system. We apply the methodology to picture such imbalances as fundamental drivers behind the tragedy of the commons. And we apply it to go deeper into a specific business example in this context, a complex case of resource exploitation in Far East Asia. The CLD analyses inform a discussion on the interplay between societies on the one hand, represented by the Government and its legislature, and the private sector with its companies, consumers and market on the other. Our study confirms that unsustainability can only be understood and addressed at the systemic level, encompassing both natural and social systems, where also the virtual and emergent systems of modern civilization are considered. The results show that a market economy can only be sustainable as well as really free, when embedded in a systemic and balanced interplay between the actors on the arena. The provision of the market arena with well thought-through rules of the game, offered by a well-functioning democratic society, is needed. The challenge for leaders in business and society is to be able to grasp the causalities of the whole system, and let this guide and shape sustainable goals as well as leadership and management in coherence with such goals. [ABSTRACT FROM AUTHOR]

This paper provides an overview of an inherently quantitative scenario philosophy for systems analysis and innovative concept design in the context of the Air Transportation System (ATS). A general perspective of the ATS is visualized in an “atomic model” with surrounding external scenario factors and the aircraft as the key connecting element between the main stakeholders: manufacturers, airlines, air navigation service providers (ANSPs) and airports. An iterative waterfall model is presented, which serves as a mental model of integration and decomposition over cascades of levels of detail from global scenario level to a single technology. The difference between classical scenario technique and a quantitative, yet participatory methodology of developing scenarios for the ATS is described. In order to integrate and decompose over a large span of levels of details, concept design and synthesis is as important as analysis. Further, quantitative scenario development may be considered as the synthesis of a skillful manipulation of a model deck. Scenario Gaming can be a method to simulate the settlement on requirements of complex socio-technological systems with multiple stakeholders and conflicting perspectives under radically changing boundary conditions. Scenario thinking can be an innovative and explorative instrument of participatory futurology, if not reduced to a mere “input for a tool chain”. [ABSTRACT FROM AUTHOR]

Although Helium–Xenon mixture cooled small reactor has been widely concerned, there is no mature thermal calculation software that can be applied to Helium–Xenon mixture cooled small reactor in China. In this paper, a semi empirical formula used to predict the physical properties of binary inert gas mixtures is used to establish a physical property calculation model of Helium–Xenon mixture gas mixtures, and the flow and heat transfer calculation model, turbine model and compressor model are modified and improved, so as to achieve the calculation of the Brayton cycle system. The function of the original system analysis program is expanded and improved, and the simulation program for he xenon mixed gas reactor system is developed. At the same time, the closed Brayton cycle system is established by using the system analysis program developed in this paper, and the calculation results are compared with the design values. The maximum relative error is 6.9%. The steady-state operation results of the model are in good agreement with the design operation parameters, which proves the applicability of the improved simulation model. The steady-state response characteristics analysis, the introduction of positive and negative reactivity accidents and the calculation of transient conditions such as step load drop of the reactor were carried out. The overall trend is the same as the literature survey results. The results show that the system analysis program developed in this paper is suitable for the analysis of the Brayton cycle system of Helium–Xenon mixture cooled small reactor. [ABSTRACT FROM AUTHOR]

• Battery chemistry changes can create problem shifts from Co and Ni to P and Li. • Recycling will not play a significant role in this decade. • Primary demand can be reduced by improving efficiency of Li, Al, Mn, and P recycling. • Material supply risks can be effectively reduced by changes in lifestyle. • The MATILDA model can be used as a basis to build on in future studies. The exponential increase in lithium-ion battery (LIB) demand for electric vehicles (EVs) has sparked material supply concerns, which makes the understanding of the LIB system and its drivers a pertinent issue. To understand the uncertainty and sensitivity around these drivers, we introduce the MATerIaL Demand and Availability (MATILDA) model. We investigate resource use within the global LIB cycle in the context of EVs and the potential secondary material supply generated by alternative scenarios. Using this dynamic, multi-layer material flow analysis model, we conducted a detailed, time-explicit sensitivity analysis to broaden our understanding of the critical factors affecting resource supply. We identified potential problem shifts between Co, P, Ni, and Li and evaluated alternative strategies to mitigate their criticality over time. We show that social paradigm shifts such as using fewer, smaller vehicles as well as technological developments can play an important role in enabling a sustainable transition. [ABSTRACT FROM AUTHOR]

Optimal selection of energy storage technologies is critical to ensure reliable integration of intermittent and often uncertain renewable energy in electricity grids. The consideration of a diverse set of energy storage technologies is required for a more sustainable deployment of energy storage. We present THESEUS (TecHno-Economic framework for Systematic Energy storage Utilization and downSelection), which is a comprehensive framework for the optimal selection, design and operation of energy storage systems. THESEUS includes rigorous models of major energy storage technologies at different maturity levels, such as thermal storage using phase-change materials or molten salt, cryogenic storage, mechanical storage in the form of compressed air and pumped hydro storage, chemical storage using hydrogen, and electrochemical storage in the form of lithium-ion, sodium sulfur and vanadium flow batteries. An illustrative case study on state-wide prospective energy storage shows that storage integration with fossil power plants could reduce the cost of meeting the grid energy demand by 20%, with mechanical storage as the best suited technology. Although high-temperature thermal storage has low storage efficiency, it is optimal for integration with renewable energy plants. In addition, Li-ion batteries are optimal for high ramping but low storage duration requirements. Such insights can enable the deployment of both existing and emerging energy storage technologies to facilitate a smooth transition to a clean energy future. • Development of a mathematical programming-based decision framework. • Nine energy storage technologies embedded in the optimization framework. • Techno-economic study for various power demand and renewable penetration conditions. • Evaluation of a complex integrated system with storage and power plant dynamics. • Comparison of emerging and mature energy storage technologies for clean energy. [ABSTRACT FROM AUTHOR]

Doping remains an intractable issue in sport and occurs in a complex and dynamic environment comprising interactions between individual, situational, and environmental factors. Anti-doping efforts have previously predominantly focused on athlete behaviours and sophisticated detection methods, however, doping issues remain. As such, there is merit in exploring an alternative approach. The aim of this study was to apply a systems thinking approach to model the current anti-doping system for four football codes in Australia, using the Systems Theoretic Accident Model and Processes (STAMP). The STAMP control structure was developed and validated by eighteen subject matter experts across a five-phase validation process. Within the developed model, education was identified as a prominent approach anti-doping authorities use to combat doping. Further, the model suggests that a majority of existing controls are reactive, and hence that there is potential to employ leading indicators to proactively prevent doping and that new incident reporting systems could be developed to capture such information. It is our contention that anti-doping research and practice should consider a shift away from the current reactive and reductionist approach of detection and enforcement to a proactive and systemic approach focused on leading indicators. This will provide anti-doping agencies a new lens to look at doping in sport. [ABSTRACT FROM AUTHOR]

The foundation of a healthy marine environment is central to the ecosystem-based management approach and is recommended for achieving sustainable development outcomes in marine spatial planning. Algoa Bay, South Africa, features a metropolitan area, protected natural area and hosts a range of uses that are closely interconnected with the health of the marine system. Future trajectories of marine uses and related marine sustainability goals are expected to develop according to shifting needs of various sectors operating in the bay. We therefore leverage the application of system dynamics modelling, to explore these trends and the underlying feedback effects between marine uses and the marine environment by developing the Algoa Marine Systems Analysis Tool. The model is used to investigate sustainability outcomes under alternative scenarios over time, and demonstrates how multiple, cross-sectoral management interventions can result in system-wide change and can be used to achieve desirable marine sustainability goals in the long-term. [Display omitted] • A system dynamics model explores the temporal change of marine activities to inform ecosystem-based marine spatial planning. • Trade-offs between marine sustainability goals are explored in four scenarios. • The model identifies leverage points for management or policy interventions. • A model interface facilitates model use in a collaborative planning environment. [ABSTRACT FROM AUTHOR]

After the Great East Japan Earthquake, Japanese energy policy strategies have been directed towards seeking more diversified energy options, especially fuel switching to gas, rapid introduction of renewable energy, and pushing towards a hydrogen economy. While a secure supply of energy, or energy security, is typically argued within the context of energy resources, little consideration for energy policy is given to mineral resources used in various energy technologies. Many studies have addressed the specific mineral elements in technologies by borrowing energy scenarios from authorities (e.g., The International Energy Agency (IEA) energy technology perspectives (ETP)). Some have applied empirical estimation models such as logistic functions for their future demand projections. In this study, we used our own resource balance models incorporating resources of energy, non-fuel minerals, biomass and food, to illustrate future consumption paths for non-fuel minerals (including scarce metals) as well as our own energy and climate policy scenarios. Our approach is complementary, not a substitute, offering more insights to existing studies on energy-mineral nexus approaches. [ABSTRACT FROM AUTHOR]

We determine the optimal configuration of a transmutation reactor based on a low-aspect-ratio tokamak. For self-consistent determination of the radial build of the reactor components, we couple a tokamak systems analysis with a radiation transport calculation. The inboard radial build of the reactor components is obtained from plasma physics and engineering constraints, while outboard radial builds are mainly determined by constraints on neutron multiplication, the tritium-breeding ratio, and the power density. We show that the breeding blanket model has an effect on the radial build of a transmutation blanket. A burn cycle has to be determined to keep the fast neutron fluence plasma-facing material below its radiation damage limit. We show that the radial build of the transmutation reactor components and the equilibrium fuel cycle play a major role in determining the transmutation characteristics. [ABSTRACT FROM AUTHOR]

Despite significant progress, road trauma continues to represent a global safety issue. In Queensland (Qld), Australia, there is currently a focus on preventing the ‘fatal five’ behaviours underpinning road trauma (drug and drink driving, distraction, seat belt wearing, speeding, and fatigue), along with an emphasis on a shared responsibility for road safety that spans road users, vehicle manufacturers, designers, policy makers etc. The aim of this article is to clarify who shares the responsibility for road safety in Qld and to determine what control measures are enacted to prevent the fatal five behaviours. This is achieved through the presentation of a control structure model that depicts the actors and organisations within the Qld road transport system along with the control and feedback relationships that exist between them. Validated through a Delphi study, the model shows a diverse set of actors and organisations who share the responsibility for road safety that goes beyond those discussed in road safety policies and strategies. The analysis also shows that, compared to other safety critical domains, there are less formal control structures in road transport and that opportunities exist to add new controls and strengthen existing ones. Relationships that influence rather than control are also prominent. Finally, when compared to other safety critical domains, the strength of road safety controls is brought into question. [ABSTRACT FROM AUTHOR]

Analyzing conflicts in non-functional requirements is a major task in large software systems development projects. Many of the non-functional requirements that accumulate vary over time. Systems analysts often maintain non-functional requirements incrementally. Requirement information overload and employee turnover problems may complicate conflict detection in the non-functional requirement evolution process. This work proposes a conflict detector in non-functional requirement evolution (CDNFRE) system that uses ontologies as a theoretical foundation for automatically detecting conflicts. Requirement metadata and conflict detection rules and their associated requirement generation and conflict detection processes are proposed for the CDNFRE mechanism. A prototype is developed. A case study of electronic commerce in a television station company demonstrates the feasibility and effectiveness of the proposed CDNFRE system. [ABSTRACT FROM AUTHOR]

Objectives Checklists are being introduced to enhance patient safety, but the results have been mixed. The goal of this research is to understand why time-outs and checklists are sometimes not effective in preventing surgical adverse events and to identify additional measures needed to reduce these events. Methods A total of 380 consecutive patients underwent complex cardiac surgery over a 24-month period between November 2011 and November 2013 at an academic medical center, out of a total of 529 cardiac cases. Elective isolated aortic valve replacements, mitral valve repairs, and coronary artery bypass graft surgical procedures (N = 149) were excluded. A time-out was conducted in a standard fashion in all patients in accordance with the World Health Organization surgical checklist protocol. Adverse events were classified as anything that resulted in an operative delay, nonavailability of equipment, failure of drug administration, or unexpected adverse clinical outcome. These events and their details were collected every week and analyzed using a systemic causal analysis technique using a technique called CAST (causal analysis based on systems theory). This analytic technique evaluated the sociotechnical system to identify the set of causal factors involved in the adverse events and the causal factors explored to identify reasons. Recommendations were made for the improvement of checklists and the use of system design changes that could prevent such events in the future. Results Thirty events were identified. The causal analysis of these 30 adverse events was carried out and actionable events classified. There were important limitations in the use of standard checklists as a stand-alone patient safety measure in the operating room setting, because of multiple factors. Major categories included miscommunication between staff, medication errors, missing instrumentation, missing implants, and improper handling of equipment or instruments. An average of 3.9 recommendations were generated for each adverse event scenario. Conclusions Time-outs and checklists can prevent some types of adverse events, but they need to be carefully designed. Additional interventions aimed at improving safety controls in the system design are needed to augment the use of checklists. Customization of checklists for specialized surgical procedures may reduce adverse events. [ABSTRACT FROM AUTHOR]

Human-driven alterations to freshwater ecosystems are leading to a global decline of river function and biodiversity. In our experience, managers want to be given many possible options to restore freshwater ecosystems that are workable within spatial, temporal, operational, and budgetary constraints of the system. Correspondingly, a new field for systematic river restoration planning has emerged through the use of well-established systems design concepts like multi-objective optimization and tradeoff analysis. In this article, we propose a decision framework for systematic river restoration planning where economic-environment systems design and tradeoff analyses are employed as a concurrent planning procedure before restoration interventions are implemented. Heuristic optimization and multi-criteria decision analysis methods are proposed to systematically design and objectively evaluate non-dominated economic-environment tradeoffs associated with restoration strategies within a watershed, and to provide a short-list of viable restoration alternatives to decision makers for negotiation and implementation. The proposed framework has the capacity to make science-based information and sophisticated decision support methods available for stakeholder deliberation. To illustrate the phases of the framework, we use a published case study of systematic restoration planning in South East Queensland, Australia. [ABSTRACT FROM AUTHOR]

Between 2002 and 2014 there have been over 150 reported incidents, including 4 fatalities, involving motor vehicles on the world heritage listed sand island Fraser Island (K’gari), off the southern Queensland coast, Australia. While regulation has been established, the beach as a roadway environment is complex and is a unique challenge for drivers. This paper describes the results of applying two systems analysis approaches, Accimap and Cognitive Work Analysis (CWA), to explore beach driving. Accimap is used to describe the actors within the system and the contributory factors involved in two recent fatal incidents. CWA is then used to describe the beach driving system within which these accidents are occurring, including the range of constraints impacting behaviour. The findings show that beaches present as complex multifaceted driving environments with a variety of competing and conflicting priorities. Further, the systems lens adopted enabled exploration of a range of contributory factors and revealed alternate likely pathways of accident causation and dependence within the management and regulation of beaches as roads. In closing we articulate a research agenda designed to enhance our understanding of the cultural, economic, and social implications of beach and off-road driving to improve safety and stakeholder coordination. [ABSTRACT FROM AUTHOR]

The Columbia Basin in the Pacific Northwest is a highly productive area for potatoes in the United States. Here, nitrate is the most frequently documented groundwater contaminant, and the challenge of maximizing crop productivity while minimizing the nitrate pollution still remains. This study assessed the responses of tuber yield, nitrate leaching, and profit margin to irrigation water amount, irrigation interval, nitrogen application rate, and soil type using 30 years of historical weather data and two representative soils in three locations of this region. A potato model was used to simulate the response variables for a total of 7500 scenarios (5 irrigation intervals × 5 irrigation amounts × 5 nitrogen rates × 2 soil types × 30 years) for each location. The results showed that nitrate leaching was greater with a larger irrigation—, a longer irrigation interval, a higher nitrogen rate, and a lighter soil. Tuber yield was larger with a smaller irrigation, a higher nitrogen rate, and a heavier soil. Profit margin was larger with a smaller irrigation and a heavier soil. The optimum amount of irrigation water for the study region was 400 mm, at which both tuber yields and profit margins were the largest with the nitrogen application rate of 336 kg ha −1 . The increase in leaching with a larger irrigation was smaller for a longer irrigation interval and a lighter soil but larger for a higher nitrogen rate. These findings might be helpful to potato growers in this region in identifying irrigation and nitrogen application rates aimed toward maximizing yields and profits while minimizing the nitrate contamination of groundwater. [ABSTRACT FROM AUTHOR]

As nuclear power expands, technical, economic, political, and environmental analyses of nuclear fuel cycles by simulators increase in importance. To date, however, current tools are often fleet-based rather than discrete and restrictively licensed rather than open source. Each of these choices presents a challenge to modeling fidelity, generality, efficiency, robustness, and scientific transparency. The Cyclus nuclear fuel cycle simulator framework and its modeling ecosystem incorporate modern insights from simulation science and software architecture to solve these problems so that challenges in nuclear fuel cycle analysis can be better addressed. A summary of the Cyclus fuel cycle simulator framework and its modeling ecosystem are presented. Additionally, the implementation of each is discussed in the context of motivating challenges in nuclear fuel cycle simulation. Finally, the current capabilities of Cyclus are demonstrated for both open and closed fuel cycles. [ABSTRACT FROM AUTHOR]

An increasing intensity of operations means that the longstanding safety issue of rail level crossings is likely to become worse in the transport systems of the future. It has been suggested that the failure to prevent collisions may be, in part, due to a lack of systems thinking during design, crash analysis, and countermeasure development. This paper presents a systems analysis of current active rail level crossing systems in Victoria, Australia that was undertaken to identify design requirements to improve safety in future rail level crossing environments. Cognitive work analysis was used to analyse rail level crossing systems using data derived from a range of activities. Overall the analysis identified a range of instances where modification or redesign in line with systems thinking could potentially improve behaviour and safety. A notable finding is that there are opportunities for redesign outside of the physical rail level crossing infrastructure, including improved data systems, in-vehicle warnings and modifications to design processes, standards and guidelines. The implications for future rail level crossing systems are discussed. [ABSTRACT FROM AUTHOR]

As geomorphologists embrace ever more sophisticated theoretical frameworks that shift from simple notions of evolution towards single steady equilibria to recognise the possibility of multiple response pathways and outcomes, morphodynamic modellers are facing the problem of how to keep track of an ever-greater number of system feedbacks. Within coastal geomorphology, capturing these feedbacks is critically important, especially as the focus of activity shifts from reductionist models founded on sediment transport fundamentals to more synthesist ones intended to resolve emergent behaviours at decadal to centennial scales. This paper addresses the challenge of mapping the feedback structure of processes controlling geomorphic system behaviour with reference to illustrative applications of Causal Loop Analysis at two study cases: (1) the erosion–accretion behaviour of graded (mixed) sediment beds, and (2) the local alongshore sediment fluxes of sand-rich shorelines. These case study examples are chosen on account of their central role in the quantitative modelling of geomorphological futures and as they illustrate different types of causation. Causal loop diagrams, a form of directed graph, are used to distil the feedback structure to reveal, in advance of more quantitative modelling, multi-response pathways and multiple outcomes. In the case of graded sediment bed, up to three different outcomes (no response, and two disequilibrium states) can be derived from a simple qualitative stability analysis. For the sand-rich local shoreline behaviour case, two fundamentally different responses of the shoreline (diffusive and anti-diffusive), triggered by small changes of the shoreline cross-shore position, can be inferred purely through analysis of the causal pathways. Explicit depiction of feedback-structure diagrams is beneficial when developing numerical models to explore coastal morphological futures. By explicitly mapping the feedbacks included and neglected within a model, the modeller can readily assess if critical feedback loops are included. [ABSTRACT FROM AUTHOR]

Non-compliance with regulation can be a major reason for policy ineffectiveness. Environmental non-compliance can cause environmental harm and undermine the sustainability of resource uses through, for example, overexploitation of water resources. If environmental non-compliance is identified as an issue, it is important to understand why it is occurring so that the causes can be effectively addressed. This paper reports empirical research conducted to identify the reasons why water users in two coastal irrigation areas in Queensland, Australia, may be taking water in excess of license conditions and thereby committing water theft. It applied the Table-of-Eleven (T11) framework, which distinguishes between ‘enforcement dimensions’, i.e. , regulatory aspects meant to detect and deter non-compliance, and ‘spontaneous compliance’ dimensions. The research involved 67 water users of whom 24 participated in focus group discussions and 43 in face-to-face interviews. The research findings suggest that most water users are compliant with water rules principally because of strong spontaneous compliance, which is chiefly grounded in the belief that the rules are required to safeguard a common water resource. The research results suggest, however, that some water users may be intentionally taking water in excess of license conditions in order to maximize business profitability. Non-compliance is underpinned by perceived low probability of successful prosecution and a comparatively small penalty if a breach can indeed be proven. From a water management perspective, the findings highlight the critical role of ongoing education and communication efforts for maintaining high levels of spontaneous compliance. Stronger deterrents may be needed to address the intentional unlawful taking of water in the given context, including increasing penalties to ensure fines result in a net cost to offenders and reduction of water entitlements of repeat offenders. Improvements in water administrative processes can minimize the likelihood of offenders escaping a penalty. [ABSTRACT FROM AUTHOR]

The depletion of natural resources, climate change and energy security are some of today's societal challenges. One way to address these is through anaerobic digestion of food waste, which provides multiple benefits such as waste treatment, nutrient recycling and renewable energy, such as biogas. Biogas solutions tend to vary, so to gain a holistic understanding of their pros and cons there is a need to use a common analytical approach and simultaneously consider several issues. This study has analysed the climate impact, primary energy use, nutrient recycling potential, and resource cost of producing biogas from food waste in three Swedish biogas plants with different setups. In addition, several scenarios representing changes in the existing systems were analysed. The study aims to provide insights into factors that affect the performance of biogas production from food waste. The method applied is based on life cycle analysis and key performance indicators (KPIs), which were used to compare and analyse the performance of the biogas systems. The analysis synthesises a large amount of information about the performance of these systems and their sub-systems. Despite significant differences between the studied cases, all led to the production of biomethane with a low climate impact (62–80% less climate impact in grCO2eq/MJ compared with the fossil reference), low non-renewable primary energy use (16–31% MJ per MJ delivered biomethane), and significant nutrient recovery (e.g., 52–86% of phosphorus content of food waste was delivered as biofertilizer). In addition to the collection system, the efficiency of pretreatment, the choice of energy system (e.g., for heating the biogas plant), and a suitable digestate treatment were found to be among the main factors that influence the overall performance of these systems. [Display omitted] • Systems analysis of three Swedish biogas production plants based on food waste. • Seven key performance indicators to capture multiple functions of biogas production. • Biogas production with 62–80% less climate impact than the fossil reference. • Primary energy use of the delivered biogas was 16–31% of the delivered biogas. • 52–86% of the phosphorous content of food waste were recovered as biofertilizer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sustainable process development for production of lignin hydrogel. • Heat integration led to net heating and cooling energy reductions of 78.9 and 83.4%. • Minimum selling price (MSP) of hydrogel was estimated to be 2,141 US$/ton. • Net emissions of 2.8 kg CO 2 eq. and 1.1 kg Oil eq./ kg lignin hydrogel was estimated. In this study, an effort has been undertaken to study process design, techno-economic analysis, and life-cycle assessment (LCA) of lignin hydrogel (LH) which has potential applications in environmental remediation. Minimum selling price (MSP) of LHs has been estimated to be 2,141 US$/ton and it lies within the range of market price (1,420–2,280 US$/ton) for commercial coagulants. Further, sensitivity analysis has been conducted and it was observed that "% efficiency of lignin hydrogel production" and "lignin price" were the most influential parameters. Uncertainty analysis has also been conducted to study the influence of volatility in the market price of lignin and total capital investment on MSP of LH. From LCA study, it was estimated that the proposed process will emit 2.8 kg CO 2 eq. and 1.1 kg Oil eq./kg lignin hydrogel. The developed process can be utilized for lignin upgradation in biorefineries to develop economically feasible and sustainable processes. [ABSTRACT FROM AUTHOR]

Our ability to adapt to climate change is not boundless, and previous modeling efforts show that future policy decisions about climate change are affected when adaptation limits are exceeded. Adaptation limits are delineated by capacity thresholds, after which climate damages begin to overwhelm the adaptation response and net adaptation goes negative. The levels of such thresholds depend on the complex interaction of different environmental (climatic and ecological) and human response (technological and societal) systems. In this paper, the interactions among these sub-systems are explored and four novel archetypical climate damage and adaptation response systems are developed. These damage–response systems can be described by the level of their adaptation limits thresholds, the pathways of adaptation capacity degradation and failure, and the recoverability or permanence of such climate losses once the adaptation limits have been surpassed. Policy options upon reaching the limits to adaptation include investment in more of the same technology, implementation of new and more effective adaptation, or transformational adaptation that allows the damage–response system to become more resilient. Attention is drawn to the need for greater understanding of the uncertainties of adaptation limits, how to raise the effective capacities and lifetime ranges of adaptation (and thus delay adaptation failure), and what policy options exist when adaptation limits are breached. [ABSTRACT FROM AUTHOR]

Transitions management (TM) is emerging as an approach to governing complex sustainability problems. Critiques point to the need to understand dynamics of system change, particularly, with regard to actor agency at micro and meso scales. This paper begins to address this scholarly gap by first, developing an analytical framework of the institutional context of a transition that recognizes forms of agency. Second, a method to apply the framework to empirical cases of urban water socio-technical systems to map their institutional context is developed. The results revealed: i) ways to identify problematic features of current systems and underlying cognitive and normative frames, to assist with envisioning and transition pathway development, ii) a method of system analysis that can target leverage points for strategizing transitions agendas and experiments, and iii) a dynamic description of the system to assist with evaluating TM interventions and monitoring transitions. By providing a systems analysis cognizant of contextual dynamics and targeted to the knowledge needs of TM activities, this analytical tool shows promise for improving TM through further empirical application and research. [ABSTRACT FROM AUTHOR]

Several methods for physical pre-treatments of source sorted organic fraction of municipal solid waste (SSOFMSW) before for anaerobic digestion (AD) are available, with the common feature that they generate a homogeneous slurry for AD and a dry refuse fraction for incineration. The selection of efficient methods relies on improved understanding of how the pre-treatment impacts on the separation and on the slurry’s AD. The aim of this study was to evaluate the impact of the performance of physical pre-treatment of SSOFMSW on greenhouse-gas (GHG) emissions and on the economy of an AD system including a biogas plant with supplementary systems for heat and power production in Sweden. Based on the performance of selected Swedish facilities, as well as chemical analyses and BMP tests of slurry and refuse, the computer-based evaluation tool ORWARE was improved as to accurately describe mass flows through the physical pre-treatment and anaerobic degradation. The environmental and economic performance of the evaluated system was influenced by the TS concentration in the slurry, as well as the distribution of incoming solids between slurry and refuse. The focus to improve the efficiency of these systems should primarily be directed towards minimising the water addition in the pre-treatment provided that this slurry can still be efficiently digested. Second, the amount of refuse should be minimised, while keeping a good quality of the slurry. Electricity use/generation has high impact on GHG emissions and the results of the study are sensitive to assumptions of marginal electricity and of electricity use in the pre-treatment. [ABSTRACT FROM AUTHOR]

Sensitivity analysis represents an important step in improving the understanding and use of environmental models. Indeed, by means of global sensitivity analysis (GSA), modellers may identify both important ( factor prioritisation ) and non-influential ( factor fixing ) model factors. No general rule has yet been defined for verifying the convergence of the GSA methods. In order to fill this gap this paper presents a convergence analysis of three widely used GSA methods (SRC, Extended FAST and Morris screening) for an urban drainage stormwater quality–quantity model. After the convergence was achieved the results of each method were compared. In particular, a discussion on peculiarities, applicability, and reliability of the three methods is presented. Moreover, a graphical Venn diagram based classification scheme and a precise terminology for better identifying important, interacting and non-influential factors for each method is proposed. In terms of convergence, it was shown that sensitivity indices related to factors of the quantity model achieve convergence faster. Results for the Morris screening method deviated considerably from the other methods. Factors related to the quality model require a much higher number of simulations than the number suggested in literature for achieving convergence with this method. In fact, the results have shown that the term “screening” is improperly used as the method may exclude important factors from further analysis. Moreover, for the presented application the convergence analysis shows more stable sensitivity coefficients for the Extended-FAST method compared to SRC and Morris screening. Substantial agreement in terms of factor fixing was found between the Morris screening and Extended FAST methods. In general, the water quality related factors exhibited more important interactions than factors related to water quantity. Furthermore, in contrast to water quantity model outputs, water quality model outputs were found to be characterised by high non-linearity. [ABSTRACT FROM AUTHOR]

Heat demand is a large contributor to greenhouse gas (GHG) emissions in the European Union (EU), as heat is largely produced using fossil fuel resources. Extended use of district heating (DH) could reduce climate impact, as DH systems can distribute heat produced in efficient combined heat and power (CHP) plants and industrial excess heat, thus utilising heat that would otherwise be wasted. The difficulty to estimate and compare GHG emissions from DH systems can however constitute an obstacle to an expanded implementation of DH. There are several methods for GHG emission assessments that may be used with varying assumptions and system boundaries. The aim of this paper is to illuminate how methodological choices affect the results of studies estimating GHG emissions from DH systems, and to suggest how awareness of this can be used to identify possibilities for GHG emission reductions. DH systems with CHP production and industrial excess heat are analysed and discussed in a systems approach. We apply different methods for allocating GHG emissions between products and combine them with different system boundaries. In addition, we discuss the impact of resource efficiency on GHG emissions, using the framework of industrial symbiosis (IS). We conclude that assessments of the climate impact of DH systems should take local conditions and requirements into account. In order for heat from CHP production and industrial excess heat to be assessed on equal terms, heat should be considered a by-product regardless of its origin. That could also reveal opportunities for GHG emission reductions. [ABSTRACT FROM AUTHOR]

The aim of this paper was to study the effects on greenhouse gases and economics when a change is made in the use of industrial organic waste from external production and use of biogas (A) to internal production and use (B). The two different system solutions are studied through a systems analysis based on an industrial case. The baseline system (A) and a modified system (B) were compared and analysed. Studies show that industrial processes considered as integrated systems, including the exchange of resources between industries, can result in competitive advantages. This study focuses on the integration of internally produced biogas from food industry waste produced by a food company and the use of excess heat. Two alternative scenarios were studied: (1) the use of available excess heat to heat the biogas digester and (2) the use of a part of the biogas produced to heat the biogas digester. This study showed that the system solution, whereby excess heat rather than biogas is used to heat the biogas digester, was both environmentally and economically advantageous. However, the valuation of biomass affects the magnitude of the emissions reduction. Implementing this synergistic concept will contribute to the reaching of European Union climate targets. [ABSTRACT FROM AUTHOR]

Purpose Explore whether agent-based modeling and simulation can help healthcare administrators discover interventions that increase population wellness and quality of care while, simultaneously, decreasing costs. Since important dynamics often lie in the social determinants outside the health facilities that provide services, this study thus models the problem at three levels (individuals, organizations, and society). Methods The study explores the utility of translating an existing (prize winning) software for modeling complex societal systems and agent's daily life activities (like a Sim City style of software), into a desired decision support system. A case study tests if the 3 levels of system modeling approach is feasible, valid, and useful. The case study involves an urban population with serious mental health and Philadelphia's Medicaid population ( n = 527,056), in particular. Results Section 3 explains the models using data from the case study and thereby establishes feasibility of the approach for modeling a real system. The models were trained and tuned using national epidemiologic datasets and various domain expert inputs. To avoid co-mingling of training and testing data, the simulations were then run and compared (Section 4.1) to an analysis of 250,000 Philadelphia patient hospital admissions for the year 2010 in terms of re-hospitalization rate, number of doctor visits, and days in hospital. Based on the Student t -test, deviations between simulated vs. real world outcomes are not statistically significant. Validity is thus established for the 2008–2010 timeframe. We computed models of various types of interventions that were ineffective as well as 4 categories of interventions (e.g., reduced per-nurse caseload, increased check-ins and stays, etc.) that result in improvement in well-being and cost. Conclusions The 3 level approach appears to be useful to help health administrators sort through system complexities to find effective interventions at lower costs. [ABSTRACT FROM AUTHOR]