5,383 research outputs found

    AN ECONOMIC EVALUATION OF BEACH EROSION MANAGEMENT ALTERNATIVES

    Get PDF
    This paper examines the relative economic efficiency of three distinct beach erosion management policies — beach nourishment with shoreline armoring, beach nourishment without armoring, and shoreline retreat. The analysis focuses on (i) the recreational benefits of beaches, (ii) the property value effects of beach management, and (iii) the costs associated with the three management scenarios. Assuming the removal of shoreline armoring improves overall beach quality, beach nourishment with shoreline armoring is the least desirable of the three alternatives. The countervailing property losses under a retreat strategy are of the same order of magnitude as the foregone management costs when the beneficial effects of retreat — higher values of housing services for those houses not lost to erosion — are considered. The relative desirability of these alternative strategies depends upon the realized erosion rate and how management costs change over time.Resource /Energy Economics and Policy,

    EXPANDING THE NATIONAL FLOOD INSURANCE PROGRAM TO COVER COASTAL EROSION DAMAGE

    Get PDF
    The National Flood Insurance Program does not currently cover damage strictly attributable to coastal erosion. This paper uses the results of a nationwide survey of coastal property owners to estimate the demand for such insurance. We find that there is significant demand at prices in the range of current flood insurance premiums. Demand is influenced in the hypothesized way by increased measures of erosion risk as well as by insurance price and income.Land Economics/Use, Risk and Uncertainty,

    COSTS OF COASTAL HAZARDS: EVIDENCE FROM THE PROPERTY MARKET

    Get PDF
    A hedonic price model suggests that flooding and erosion hazards, and the actions taken against them, are major determinants of property values in American coastal areas. A zoning ordnance against new construction within the 60-year erosion hazard area would increase property values and perhaps conserve the coastal ecosystem.Environmental Economics and Policy, Land Economics/Use,

    Efficient characterization of blinking quantum emitters from scarce data sets via machine learning

    Full text link
    Single photon emitters are core building blocks of quantum technologies, with established and emerging applications ranging from quantum computing and communication to metrology and sensing. Regardless of their nature, quantum emitters universally display fluorescence intermittency or photoblinking: interaction with the environment can cause the emitters to undergo quantum jumps between on and off states that correlate with higher and lower photoemission events, respectively. Understanding and quantifying the mechanism and dynamics of photoblinking is important for both fundamental and practical reasons. However, the analysis of blinking time traces is often afflicted by data scarcity. Blinking emitters can photo-bleach and cease to fluoresce over time scales that are too short for their photodynamics to be captured by traditional statistical methods. Here, we demonstrate two approaches based on machine learning that directly address this problem. We present a multi-feature regression algorithm and a genetic algorithm that allow for the extraction of blinking on/off switching rates with >85% accuracy, and with >10x less data and >20x higher precision than traditional methods based on statistical inference. Our algorithms effectively extend the range of surveyable blinking systems and trapping dynamics to those that would otherwise be considered too short-lived to be investigated. They are therefore a powerful tool to help gain a better understanding of the physical mechanism of photoblinking, with practical benefits for applications based on quantum emitters that rely on either mitigating or harnessing the phenomenon

    Granular packings with moving side walls

    Full text link
    The effects of movement of the side walls of a confined granular packing are studied by discrete element, molecular dynamics simulations. The dynamical evolution of the stress is studied as a function of wall movement both in the direction of gravity as well as opposite to it. For all wall velocities explored, the stress in the final state of the system after wall movement is fundamentally different from the original state obtained by pouring particles into the container and letting them settle under the influence of gravity. The original packing possesses a hydrostatic-like region at the top of the container which crosses over to a depth-independent stress. As the walls are moved in the direction opposite to gravity, the saturation stress first reaches a minimum value independent of the wall velocity, then increases to a steady-state value dependent on the wall-velocity. After wall movement ceases and the packing reaches equilibrium, the stress profile fits the classic Janssen form for high wall velocities, while it has some deviations for low wall velocities. The wall movement greatly increases the number of particle-wall and particle-particle forces at the Coulomb criterion. Varying the wall velocity has only small effects on the particle structure of the final packing so long as the walls travel a similar distance.Comment: 11 pages, 10 figures, some figures in colo

    Explaining and Fixing the \u27Weak Governance Curse\u27 in Resource-Rich Least Developed Countries

    Get PDF
    There is a resource boom in the least developed countries, including those in Southern Africa. In order to translate their resource wealth into positive development outcomes in the long run, these countries need to have strong domestic governance systems. Yet, governance indicators in resource-rich LDCs have stagnated or deteriorated in the last decades. We use a new institutional analysis with a focus on path dependence theory to argue that these countries are caught in a “weak governance curse”. Besides having inherited dysfunctional governance paths from past critical junctures, rent-seeking behavior associated with resource rents constitutes a major contemporary political economy obstacle to successful governance reform in these countries. Although these dysfunctional governance systems have become extremely resilient to change, we build a theoretical case as to why global regulatory mechanisms can serve as potential tools to provoke gradual feedback effects to disrupt this negative equilibrium

    Explaining and Fixing the \u27Weak Governance Curse\u27 in Resource-Rich Least Developed Countries

    Get PDF
    There is a resource boom in the least developed countries, including those in Southern Africa. In order to translate their resource wealth into positive development outcomes in the long run, these countries need to have strong domestic governance systems. Yet, governance indicators in resource-rich LDCs have stagnated or deteriorated in the last decades. We use a new institutional analysis with a focus on path dependence theory to argue that these countries are caught in a “weak governance curse”. Besides having inherited dysfunctional governance paths from past critical junctures, rent-seeking behavior associated with resource rents constitutes a major contemporary political economy obstacle to successful governance reform in these countries. Although these dysfunctional governance systems have become extremely resilient to change, we build a theoretical case as to why global regulatory mechanisms can serve as potential tools to provoke gradual feedback effects to disrupt this negative equilibrium
    corecore