Flood lamination strategy based on a three-flood-diversion-area system management

The flood lamination has for principal objective to maintain a downstream flow at a fixed lamination level. For this goal, it is necessary to proceed to the dimensioning of the river system capacity and to make sure of its management by taking into account socio-economic and environmental constraints. The use of flood diversion areas on a river has for main interest to protect inhabited downstream areas. In this paper, a flood lamination strategy aiming at deforming the wave of flood at the entrance of the zone to be protected is presented. A transportation network modeling and a flow optimization method are proposed. The flow optimization method, is based on the modeling of a Min-Cost-Max-flow problem with a linear programming formulation. The optimization algorithm used in this method is the interior-point algorithm which allows a relaxation of the solution of the problem and avoids some non feasibility cases due to the use of constraints based on real data. For a forecast horizon corresponding to the flood episode, the management method of the flood volumes is evaluated on a 2D simulator of a river equipped with a three-flood-diversion- area system. Performances show the effectiveness of the method and its ability to manage flood lamination with efficient water storage

The Importance of Social and Government Learning in Ex Ante Policy Evaluation

We provide two methodological insights on \emph{ex ante} policy evaluation for macro models of economic development. First, we show that the problems of parameter instability and lack of behavioral constancy can be overcome by considering learning dynamics. Hence, instead of defining social constructs as fixed exogenous parameters, we represent them through stable functional relationships such as social norms. Second, we demonstrate how agent computing can be used for this purpose. By deploying a model of policy prioritization with endogenous government behavior, we estimate the performance of different policy regimes. We find that, while strictly adhering to policy recommendations increases efficiency, the nature of such recipes has a bigger effect. In other words, while it is true that lack of discipline is detrimental to prescription outcomes (a common defense of failed recommendations), it is more important that such prescriptions consider the systemic and adaptive nature of the policymaking process (something neglected by traditional technocratic advice)

Using the general link transmission model in a dynamic traffic assignment to simulate congestion on urban networks

This article presents two new models of Dynamic User Equilibrium that are particularly suited for ITS applications, where the evolution of vehicle flows and travel times must be simulated on large road networks, possibly in real-time. The key feature of the proposed models is the detail representation of the main congestion phenomena occurring at nodes of urban networks, such as vehicle queues and their spillback, as well as flow conflicts in mergins and diversions. Compared to the simple word of static assignment, where only the congestion along the arc is typically reproduced through a separable relation between vehicle flow and travel time, this type of DTA models are much more complex, as the above relation becomes non-separable, both in time and space. Traffic simulation is here attained through a macroscopic flow model, that extends the theory of kinematic waves to urban networks and non-linear fundamental diagrams: the General Link Transmission Model. The sub-models of the GLTM, namely the Node Intersection Model, the Forward Propagation Model of vehicles and the Backward Propagation Model of spaces, can be combined in two different ways to produce arc travel times starting from turn flows. The first approach is to consider short time intervals of a few seconds and process all nodes for each temporal layer in chronological order. The second approach allows to consider long time intervals of a few minutes and for each sub-model requires to process the whole temporal profile of involved variables. The two resulting DTA models are here analyzed and compared with the aim of identifying their possible use cases. A rigorous mathematical formulation is out of the scope of this paper, as well as a detailed explanation of the solution algorithm. The dynamic equilibrium is anyhow sought through a new method based on Gradient Projection, which is capable to solve both proposed models with any desired precision in a reasonable number of iterations. Its fast convergence is essential to show that the two proposed models for network congestion actually converge at equilibrium to nearly identical solutions in terms of arc flows and travel times, despite their two diametrical approaches wrt the dynamic nature of the problem, as shown in the numerical tests presented here

A New Framework for Network Disruption

Traditional network disruption approaches focus on disconnecting or lengthening paths in the network. We present a new framework for network disruption that attempts to reroute flow through critical vertices via vertex deletion, under the assumption that this will render those vertices vulnerable to future attacks. We define the load on a critical vertex to be the number of paths in the network that must flow through the vertex. We present graph-theoretic and computational techniques to maximize this load, firstly by removing either a single vertex from the network, secondly by removing a subset of vertices.Comment: Submitted for peer review on September 13, 201

A Roadmap to Reduce U.S. Food Waste by 20 Percent

The magnitude of the food waste problem is difficult to comprehend. The U.S. spends $218 billion a year -- 1.3% of GDP -- growing, processing, transporting, and disposing of food that is never eaten. The causes of food waste are diverse, ranging from crops that never get harvested, to food left on overfilled plates, to near-expired milk and stale bread. ReFED is a coalition of over 30 business, nonprofit, foundation, and government leaders committed to building a different future, where food waste prevention, recovery, and recycling are recognized as an untapped opportunity to create jobs, alleviate hunger, and protect the environment -- all while stimulating a new multi-billion dollar market opportunity. ReFED developed A Roadmap to Reduce U.S. Food Waste as a data-driven guide to collectively take action to reduce food waste at scale nationwide.This Roadmap report is a guide and a call to action for us to work together to solve this problem. Businesses can save money for themselves and their customers. Policymakers can unleash a new wave of local job creation. Foundations can take a major step in addressing environmental issues and hunger. And innovators across all sectors can launch new products, services, and business models. There will be no losers, only winners, as food finds its way to its highest and best use

Inside out: the case for improving mental health care across the criminal justice system

Inside Out: the case for improving mental health care across the criminal justice syste

Healthcare not Handcuffs: Putting the Affordable Care Act to Work for Criminal Justice and Drug Policy Reform

The Affordable Care Act (ACA) sets the stage for a new health-oriented policy framework to address substance use and mental health disorders. By dramatically expanding and funding healthcare coverage to millions of currently uninsured people, the ACA represents a remarkable opportunity for criminal justice and drug policy reform advocates to advance efforts for policies promoting safe and healthy communities, without excessive reliance on the criminal justice solutions that have become so prevalent under the War on Drugs. This paper is intended as a starting framework for criminal justice and drug policy advocates to navigate the ACA, and to take advantage of the conceptual and practical opportunities it offers for shifting the conversation and the landscape. Part One of this paper describes some of the major provisions of the ACA relevant to our work: the health insurance requirement; the places many people will buy insurance, called health exchanges; Medicaid expansion; insurance coverage requirements for substance use and mental health disorders; and opportunities for improved models of coordinated care. Part Two of this paper outlines a series of practical recommendations, including program and policy examples and suggested action steps, across three broad categories: ensuring access to healthcare, leveraging the ACA to reduce incarceration, and moving from a criminilization-based drug policy approach to one rooted in health