A critical review of resource recovery from municipal wastewater treatment plants : market supply potentials, technologies and bottlenecks

In recent decades, academia has elaborated a wide range of technological solutions to recover water, energy, fertiliser and other products from municipal wastewater treatment plants. Drivers for this work range from low resource recovery potential and cost effectiveness, to the high energy demands and large environmental footprints of current treatment-plant designs. However, only a few technologies have been implemented and a shift from wastewater treatment plants towards water resource facilities still seems far away. This critical review aims to inform decision-makers in water management utilities about the vast technical possibilities and market supply potentials, as well as the bottlenecks, related to the design or redesign of a municipal wastewater treatment process from a resource recovery perspective. Information and data have been extracted from literature to provide a holistic overview of this growing research field. First, reviewed data is used to calculate the potential of 11 resources recoverable from municipal wastewater treatment plants to supply national resource consumption. Depending on the resource, the supply potential may vary greatly. Second, resource recovery technologies investigated in academia are reviewed comprehensively and critically. The third section of the review identifies nine non-technical bottlenecks mentioned in literature that have to be overcome to successfully implement these technologies into wastewater treatment process designs. The bottlenecks are related to economics and value chain development, environment and health, and society and policy issues. Considering market potentials, technological innovations, and addressing potential bottlenecks early in the planning and process design phase, may facilitate the design and integration of water resource facilities and contribute to more circular urban water management practices

Issues in making courseware exploitable and issues in making exploitable courseware

Part 1 of the paper, ‘Issues in making courseware exploitable’, is about dealing with the legacy of large volumes of incompatible non‐integrated courseware which are currently being generated within initiatives such as the Teaching and Learning Technology Programme (TLTP). We suggest strategies for allowing end‐users to apply courseware management techniques belatedly to current courseware developments, thereby offering ways of making the emerging courseware more exploitable than it otherwise would be. Part 2 of the paper, ‘Issues in making exploitable courseware’, takes a forward‐looking approach which recognizes that future courseware development efforts must pre‐empt these problems of incompatibility and non‐integration. Courseware development must mature to the stage where it makes use of courseware design standards, embraces a host of essential lessons from conventional software development, and recognizes the importance of courseware management issues

Multiscale Markov Decision Problems: Compression, Solution, and Transfer Learning

Many problems in sequential decision making and stochastic control often have natural multiscale structure: sub-tasks are assembled together to accomplish complex goals. Systematically inferring and leveraging hierarchical structure, particularly beyond a single level of abstraction, has remained a longstanding challenge. We describe a fast multiscale procedure for repeatedly compressing, or homogenizing, Markov decision processes (MDPs), wherein a hierarchy of sub-problems at different scales is automatically determined. Coarsened MDPs are themselves independent, deterministic MDPs, and may be solved using existing algorithms. The multiscale representation delivered by this procedure decouples sub-tasks from each other and can lead to substantial improvements in convergence rates both locally within sub-problems and globally across sub-problems, yielding significant computational savings. A second fundamental aspect of this work is that these multiscale decompositions yield new transfer opportunities across different problems, where solutions of sub-tasks at different levels of the hierarchy may be amenable to transfer to new problems. Localized transfer of policies and potential operators at arbitrary scales is emphasized. Finally, we demonstrate compression and transfer in a collection of illustrative domains, including examples involving discrete and continuous statespaces.Comment: 86 pages, 15 figure

Experimental study of pedestrian flow through a bottleneck

In this work the results of a bottleneck experiment with pedestrians are presented in the form of total times, fluxes, specific fluxes, and time gaps. A main aim was to find the dependence of these values from the bottleneck width. The results show a linear decline of the specific flux with increasing width as long as only one person at a time can pass, and a constant value for larger bottleneck widths. Differences between small (one person at a time) and wide bottlenecks (two persons at a time) were also found in the distribution of time gaps.Comment: accepted for publication in J. Stat. Mec

Scaling readiness: Concepts, practices, and implementation.

Scaling Readiness is an approach that can support organizations, projects, and programs in achieving their ambitions to scale innovations and achieve impact. Scaling Readiness encourages critical reflection on how ready innovations are for scaling, and what appropriate actions could accelerate or enhance scaling

Technology infrastructure in information technology industries

Abstract not availableeconomics of technology business administration and economics

From centrality to intermediacy in the global transport network? Ukraine’s trials and tribulations as a potential transit country

Ukraine currently is in a very complex economic and political situation, which in itself represents a pivotal point for its further recovery and evolution. Nevertheless, the rise of economic centres in Eastern and Central Europe creates opportunities for Ukraine to develop short sea shipping services (via the Black Sea) and water and land-based hub-feeder networks to and from these areas. This paper provides an academic study of the potential of Ukraine in taking up a role in emerging distribution systems in East and Central Europe facilitating the cargo transportation from regions such as Central Asia, Caucasus and even more distant overseas areas. Based on the concepts of intermediacy and centrality as introduced by Fleming and Hayuth (1994) the role of Ukraine in the global and regional transport networks will be analysed in order to assess to what extent particular regions in Ukraine can serve as important gateways to Europe. An extensive review and synthesis of the published studies during the last 20 years on Ukraine’s transit flows and transit function will be presented. The obtained results will be contraposed to the results obtained from about 20 interviews conducted with transport business representatives in Ukraine and abroad. Based on the outcome of bottlenecks and deficiencies in Ukraine’s transport system, the optimal road map for Ukraine’s integration into the European transport network will be defined