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The common European electricity market requires both market integration and transmission grid expansion, including trans-border interconnectors. Although the benefits of increased interconnectivity are widely acknowledged, expansion of interconnectors is often very slow. This paper gathers insights on the reasons behind this grid-lock drawing on the study of the German-Polish border. Although two interconnectors already exist, the trade is blocked by unplanned electricity loop flows. A third interconnector has been discussed for years, but saw little progress in spite of declarations of support on both sides. Drawing on the existing literature on the topic of grid expansion we identify four hypotheses for the grid-lock: inadequate financing; diverging interests; governance and administration problems; and different actors' motivations, trust and security perceptions. We evaluate them using the empirical material gathered through document analysis and stakeholder interviews conducted in Germany and Poland. None of the hypotheses on its own can explain the gridlock. However, while financing has not been a major obstacle, divergent interests had an impact on the project delay, administrative and governance problems are a great hindrance on the technical level, while motivations influence interstate political relations and policy shaping. EU support and closer bilateral cooperation provide opportunities to address these challenges.

The objective of this thesis is to develop models and algorithms to plan the purchasing of reusable containers in a closed-loop supply chain where the demand is increasing. We restrict our study to a periodic review process between a single manufacturer and a single supplier. Each item is transported either in a reusable container or in a single-use disposable. Furthermore, a setup cost is paid every time new containers are purchased. Consequently, our model is similar to a lot-sizing problem with return of every item after a fixed duration. We study both cases of a deterministic demand as well as a stochastic demand. In the deterministic setting, we use dynamic programming and minimum linear-cost flows to generate polynomial time algorithms. When the demand is stochastic, we use the Markov decision process framework to develop pseudo-polynomial time heuristics for four different strategies. We show the L-natural-convexity of the cost functions for three strategies to speed up the computations. The thesis concludes with an application on a real-life supply chain.

Chaotic Behavior of an Annular Film of Liquid Unstabilized by an Interfacial Shear Stress -- Experimental Observation of Type-I and Type-II Intermittencies -- Stability of Stationary Regime of Directed Crystallization -- Bubble Evolution in Liquid-Solid Solutions Viewed as an Elementary Catastrophe -- Modelisation of Pulverization Systems: Some Aspects of Linear Stability Analysis -- Overstability in an Infinite Liquid Layer under Simultaneous Surface Tension, Buoyancy and Shear Effects -- The Numerical Investigation of Boiling Flow in Heated Channels -- A Mathematical Description of the Critical Heat Flux as a Non-Linear Dynamic Instability -- Density Wave Oscillation in a Natural Circulation Loop of Liquid Nitrogen -- Study on the Effective Parameters for the Geysering Period -- Dynamics of a Reduced Model of Two-Phase Flow in a Boiling Channel -- Bifurcations in Two-Phase Flames -- Influence of the Surface Deformability on Concentration-Dependent, Oscillatory and Stationary Convection in a Liquid Layer -- Instabilities, Mass-Transfer and Self-Organization of Heat Cycles by Interaction of Laser Radiation with Liquids -- Transverse and Longitudinal Waves at an Air-Liquid Interface in the Presence of an Adsorption Barrier -- Application of Laser-Induced Thermal Lens Oscillation to Concentration Control in Solvent Extraction Processes -- Theoretical and Experimental Investigation of Periodic Interfacial Waves between Two Viscous Fluid Layers -- Instabilities in Evaporating Liquid Films -- Kelvin-Helmholz Two-Phase Flow Instability -- Instabilities, Waves and Slugs in Pipeline Two-Phase Flows -- Instabilities and the Formation of Wave Patterns in Fluidized Beds -- Monte Carlo Simulation of Bubbling Fluidized Beds -- The Thermoconvective Instability in Hydrodynamics of Relaxational Liquids -- Dynamic Properties of Thermal Convection in Porous Medium -- Non-Linear Three Dimensional Miscible Viscous Fingering in Porous Media -- Viscous Fingering and Surface Structure Formation in Porous Media -- Transition Process of Laminar Confined Jet in Solid-Liquid Two-Phase Flow -- Two-Phase High Temperature Modelling for Granulation -- Contributors.

ABSTRACTIn this article, I present a review and tutorial of the literature on closed‐loop supply chains, which are supply chains where, in addition to typical forward flows, there are reverse flows of used products (postconsumer use) back to manufacturers. Examples include supply chains with consumer returns, leasing options, and end‐of‐use returns with remanufacturing. I classify the literature in terms of strategic, tactical, and operational issues, but I focus on strategic issues (such as when should an original equipment manufacturer (OEM) remanufacture, response to take‐back legislation, and network design, among others) and tactical issues (used product acquisition and disposition decisions). The article is written in the form of a tutorial, where for each topic I present a base model with underlying assumptions and results, comment on extensions, and conclude with my view on needed research areas.

This is a conference paper. ; Product longevity and extending product lifetimes through repair and reuse are recognised as having an important place in waste reduction strategies (Cooper, 2005; Curran & Williams, 2010). These activities, discourage the "churn" of purchasing new items (Cox et al., 2013) and also have a part to play in addressing global concerns regarding resource efficiency, contributing to slowing material flows, conserving resources, reducing energy use and decreasing environmental pollution (WRAP, 2009; ERM, 2011). As such, they have been prioritised in European Union (EU) legislation, being placed above recycling and other waste management treatments in the waste hierarchy introduced in the Waste Framework Directive (75/442/EC), and more recently in the Circular Economy Action Plan (European Commission, 2015). In order to identify key areas for improvement in maintaining products in their most useful state for an optimum time, it is pertinent to understand product flows in a post-consumer context. This paper explores a partnership between a major retailer and the reuse sector that seeks to support reuse of products discarded by consumers who have recently purchased replacement goods. It traces the movement of discarded products, outlining the roles of the different stakeholders and sets out the product pathways to reuse enabled by this partnership. It makes recommendations for policy makers to encourage the growth of such partnerships to facilitate reuse which have economic and social benefits in addition to environmental benefits that align with circular economy concepts.

Wholesale electricity markets use different market designs to handle congestion in the transmission network. We compare nodal, zonal and discriminatory pricing in general networks with transmission constraints and loop flows. We conclude that in large games with many producers who are allowed to participate in the real-time market the three market designs result in the same efficient dispatch. However, zonal pricing with counter-trading results in additional payments to producers in export-constrained nodes.

AbstractIn this article, we consider a multi‐product closed‐loop supply chain network design problem where we locate collection centers and remanufacturing facilities while coordinating the forward and reverse flows in the network so as to minimize the processing, transportation, and fixed location costs. The problem of interest is motivated by the practice of an original equipment manufacturer in the automotive industry that provides service parts for vehicle maintenance and repair. We provide an effective problem formulation that is amenable to efficient Benders reformulation and an exact solution approach. More specifically, we develop an efficient dual solution approach to generate strong Benders cuts, and, in addition to the classical single Benders cut approach, we propose three different approaches for adding multiple Benders cuts. These cuts are obtained via dual problem disaggregation based either on the forward and reverse flows, or the products, or both. We present computational results which illustrate the superior performance of the proposed solution methodology with multiple Benders cuts in comparison to the branch‐and‐cut approach as well as the traditional Benders decomposition approach with a single cut. In particular, we observe that the use of multiple Benders cuts generates stronger lower bounds and promotes faster convergence to optimality. We also observe that if the model parameters are such that the different costs are not balanced, but, rather, are biased towards one of the major cost categories (processing, transportation or fixed location costs), the time required to obtain the optimal solution decreases considerably when using the proposed solution methodology as well as the branch‐and‐cut approach. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007

Rare earth element (REE) recycling remains low at 1%, despite significant uncertainties related to future supply and demand and EU 2020 energy efficiency objectives. We use a global production network framework of REE flows from mine to REE phosphors in energy-efficient lamps to illustrate the potential of closed-loop recycling for secondary supply under different scenarios of primary supply and forecasted demand for LEDs, CFLs and LFLs. We find that different End-of-Life Recycling Rate scenarios for REE secondary supply range between meeting forecasted REE demand and filling primary supply gaps, and competing with primary supply. Our argument centres on diversifying REE sourcing with recycling and the choice between primary and secondary supply. We stress that secondary REE phosphor supply requires further policy support for lamp collection and a discussion of the value of REE phosphor recycling which underlies its economic feasibility.

PART I: THE PRACTICE OF MACROPRUDENTIAL POLICY 1. Preliminaries 2. The Incalculable Costs of Financial Crises 3. Defining Financial Stability 4. Explaining the Failure to Act 5. A Whistle-stop Tour of the Microprudential Reform Agenda 6. The Design of Macroprudential Policy 7. Enter Macroprudential Policy 8. Resilience versus Credit Smoothing 9. A Cost Benefit Analysis of Macroprudential Policy 10. Managing the Contradictions 11. The Institutions of Macroprudential Policy 12. Macroprudential Policy in the United Kingdom 13. It ain't what you do, it's the reason you do it 14. The European Dimension 15. The Global Macroprudential Agenda 16. The Instruments of Macroprudential Policy 17. The Transmission of Policy 18. Capital Surcharges 19. Contingent Capital 20. Regulating the Liquidity Cycle 21. Lender of Last Resort 22. Market Maker of Last Resort 23. The Conduct of Macroprudential Policy 24. Canaries in the Coalmine 25. Macroprudential Policy from 30,000 Feet 26. The Sherlock Holmes Approach to Macroprudential Policy 27. Systemic Stress Tests 28. Macroprudential Regulation of the SIFIs PART II: THE THEORY OF MACROPRUDENTIAL POLICY 29. The Conventional Wisdom 30. Meet the Conventional Wisdom 31. The Key Pillars of the Classical Edifice 32. Walrasian Auctioneers: Nothing Worth Shouting About 33. The Representative Agent Assumption 34. The Irrelevance of Capital Structure 35. An Unstable System 36. The Mavericks 37. Following the Herd 38. Introducing Institutions 39. Credit Balance Sheets and Asset Prices 40. The Family Tree of Financial Crises 41. The Hysteresis Loop 42. The Liquidity Cycle 43. Final Thoughts 44. Are Financial Markets Worth the Heartache 45. The Way Ahead

AbstractMinimizing duration is critical to success in many development projects. Resource allocation policies during such projects determine the fractions of resources that are to be assigned to constituent tasks. The choice of allocation policy can strongly influence project durations. But policies for reduced project duration are difficult to design and implement because of closed loop flows of work that generate dynamic demand patterns and delays in shifting resources among activities. Resource demand estimates and resource adjustment times are two policy features that managers can readily alter to influence project durations. These features are used to describe allocation policies in a relatively simple project model. Myopic and foresighted policies are distinguished by their use (or lack thereof) of rework and multiple backlogs in allocation. Optimal policies under perfect and limited managerial control are described by testing myopic and foresighted policies across a range of project complexities and adjustment times under deterministic and uncertain conditions. Counter‐intuitive results from this analysis indicate that minimum resource allocation delay does not produce minimum durations, and increasing uncertainty decreases durations under certain conditions. The model is used to explain these results. Managerial implications and future research topics are discussed. Copyright © 2007 John Wiley & Sons, Ltd.

Cardiovascular diseases (CVDs) including diseases of the heart and circulatory system are the leading cause of death in the European Union and accounted for about 37% of all deaths in 2017 (OCDE). Among CVDs, we can mention atherosclerosis, aneurysm and aortic dissection (AD). AD is a life-threatening pathology that develops when a tear occurs in the inner layer of the aorta. Blood surges into the tear and a secondary channel develops in between aorta layers. AD results in higher risks of rupture and malperfusion which makes of aortic dissection a pathology with a high mortality rate, difficult to detect in time and to treat in a lasting way. The mechanisms of its development are still poorly understood. Beyond purely biological concepts, fluid dynamics and biomechanics have contributed to AD understanding and pointed out some culprits such as alteration in stress patterns, flow distribution, and vortical flows. However, one of the main limitations in analyzing and understanding these mechanisms is flow visualization. {In vivo, routine traditional imaging that gives access to fluid velocities such as 4D-MRI or US-doppler suffers from low time and space resolutions. This is one reason why alternative techniques are developed with artificial circulation emulations to overcome human body observation limitations. The present work proposes an in vitro blood flow investigation. An aortic flow simulator was designed to emulate blood flow in aorta models (healthy and pathological) with biofidelic properties. The goal is to explore aorta hemodynamics and address the limitations encountered with in vivo traditional imaging as a complementary tool. Particle Image Velocimetry was implemented to accurately measure fluid velocities and compute quantities of interests in the context of disease mechanism understanding (shear rate, shear stress, vorticity, etc.). The bench is a circulatory mock loop that accurately recreates the cardiovascular system flowrate and pressure conditions. It accommodates healthy and pathological ...