A Checkup On Health Care Markets

Looks at key attributes of the healthcare markets in fourteen communities in order to gain a better understanding of how to help communities drive and sustain high-quality health care for patients with chronic illnesses

A Note on a "Square-Root Rule" for Reinsurance

In previous work, the current authors derived a mathematical expression for the optimal (or "saturation") number of reinsurers for a given number of primary insurers (see Powers and Shubik, 2001). In the current paper, we show analytically that, for large numbers of primary insurers, this mathematical expression provides a "square-root rule"; i.e., the optimal number of reinsurers in a market is given asymptotically by the square root of the total number of primary insurers. We note further that an analogous “fourth-root rule” applies to markets for retrocession (the reinsurance of reinsurance).Primary insurance, Reinsurance, Market size, Square-root rule

Reliability Analysis of Geosynthetic Reinforced Soil Walls

Geosynthetic reinforced soil walls have been widely used for earth retention and stabilization in many geotechnical applications. In the traditional design of geosynthetic reinforced soil walls, Allowable Stress Design (ASD) is used to address the uncertainties. However, it cannot explicitly consider the uncertainties in a systematic way in the design process; especially geotechnical uncertainties are typically at high levels and problem-specific. Traditional methods usually result in over-conservativeness, inconsistence, and empiricism in the design practice. Recently there has been a trend of the application of reliability methods for design of geosynthetic reinforced soil walls to explicitly address uncertainties in the design process and account for the actual safety and reliability level of a given design. In this paper, a series of reliability analyses of geosynthetic reinforced soil walls are performed, results from which can provide a useful decision making tool for selection of suitable design of geosynthetic reinforced soil walls based on target reliability levels. A case study is presented to demonstrate the significance of the proposed framework

Structural Reliability Analysis of Tunneling-Induced Ground Settlement and Damage to Adjacent Buildings: A Case Study using Moment Methods and FLAC2D

Tunnels are widely used for underground space development in urban areas such as mass transit. However, tunneling in heavily congested areas is a very risky operation that can impose significant damage to adjacent buildings. In the traditional analysis of tunnel structures, the deterministic approach is commonly used. The owners or regulatory agencies establish the limiting ground surface settlement value and angular distortion value for buildings as a means of preventing tunneling-induced failure and damage to adjacent buildings. In addition, significant uncertainties in geotechnical parameters exist in the prediction of tunneling-induced ground settlement and damage to adjacent buildings. Design and analysis found through the deterministic approach is often prone to violate the limiting deflection values due to these uncertainties. In this paper, a probabilistic assessment methodology is proposed to account for the stochastic nature of geotechnical parameters for tunneling-induced ground settlement and damage to adjacent buildings. This method combines both moment methods and finite difference analysis for probabilistic assessment since the performance function for tunneling analysis is usually a numerical model without an explicit function. A series of moment methods were used to evaluate the failure probability based on the solutions obtained from FLAC 2D, a commercially available finite difference code. The efficiency of the probabilistic assessment framework for tunneling-induced ground settlement and damage to adjacent buildings is demonstrated using a case study and the results provide engineers with the appropriate data to make risk based decisions

Tidal-Groundwater Study of the Slaughter Beach Salt Marsh in Slaughter Beach, DE

Seasonal and decadal monitoring of salt marsh at Slaughter Beach, DE documented long-term and short-term variations in number and sizes of salt ponds. Over 400 salt ponds ranging in size between 0.5 m2 to 0.11 km2 were identified on 5.5 km2 salt marsh platform. The purpose of this study is to quantify hydrologic conditions and measure groundwater discharge of a salt marsh, particularly the impact of tidal forces on groundwater fluctuation. Four wells with nests of mini-piezometers with ONSET Pressure Transducers were installed along a transect crossing the largest salt pond (0.11 km2) in the study area. Nests of wells, installed at depths of 1 m, 3 m, and 6 m recorded groundwater hydraulic head at five-minute intervals during a 90 day period. High resolution aerial imagery of the studied ponds was collected at peak high tide and low tide using an unmanned drone. Changes in groundwater elevation were correlated with tidal data recorded by the USGS stream gauge in Cedar Creek. Our results document the presence of 2 aquifers; deep (3m) and shallow (1m). Relationship between groundwater elevation and tidal fluctuations is strong in the deep aquifer and weak in the shallow aquifer. Analysis of drone imagery reveal no changes in the shape or size of the pond during 1 tidal cycle. Groundwater elevation decreases in proportion to distance from Cedar Creek and decreases with depth. We suggest that the deep aquifer is confined. This study has established a baseline for hydrologic investigations within the salt marsh

Spectral LADAR: Active Range-Resolved Imaging Spectroscopy

Imaging spectroscopy using ambient or thermally generated optical sources is a well developed technique for capturing two dimensional images with high per-pixel spectral resolution. The per-pixel spectral data is often a sufficient sampling of a material's backscatter spectrum to infer chemical properties of the constituent material to aid in substance identification. Separately, conventional LADAR sensors use quasi-monochromatic laser radiation to create three dimensional images of objects at high angular resolution, compared to RADAR. Advances in dispersion engineered photonic crystal fibers in recent years have made high spectral radiance optical supercontinuum sources practical, enabling this study of Spectral LADAR, a continuous polychromatic spectrum augmentation of conventional LADAR. This imaging concept, which combines multi-spectral and 3D sensing at a physical level, is demonstrated with 25 independent and parallel LADAR channels and generates point cloud images with three spatial dimensions and one spectral dimension. The independence of spectral bands is a key characteristic of Spectral LADAR. Each spectral band maintains a separate time waveform record, from which target parameters are estimated. Accordingly, the spectrum computed for each backscatter reflection is independently and unambiguously range unmixed from multiple target reflections that may arise from transmission of a single panchromatic pulse. This dissertation presents the theoretical background of Spectral LADAR, a shortwave infrared laboratory demonstrator system constructed as a proof-of-concept prototype, and the experimental results obtained by the prototype when imaging scenes at stand off ranges of 45 meters. The resultant point cloud voxels are spectrally classified into a number of material categories which enhances object and feature recognition. Experimental results demonstrate the physical level combination of active backscatter spectroscopy and range resolved sensing to produce images with a level of complexity, detail, and accuracy that is not obtainable with data-level registration and fusion of conventional imaging spectroscopy and LADAR. The capabilities of Spectral LADAR are expected to be useful in a range of applications, such as biomedical imaging and agriculture, but particularly when applied as a sensor in unmanned ground vehicle navigation. Applications to autonomous mobile robotics are the principal motivators of this study, and are specifically addressed

“The Commercial Union of the Three Americas:” Major Edward A. Burke and Transnational New South Visionaries, 1870-1928

Traditional images of the late nineteenth and early twentieth-century American South are of an inward-looking region characterized by economic stagnation, xenophobia, cultural isolation, and reactionary politics. This dissertation contends that vibrant transnational links connected the South to the wider world through an analysis of the political and economic landscape of postbellum Louisiana, the 1884 New Orleans World’s Industrial and Cotton Centennial, the Louisiana State Lottery Company, and Central America. An examination of Edward Austin Burke demonstrates that the era’s New South creed comprised a seminal transnational component. This dissertation will explore how Burke became a central cog in Louisiana’s Democratic political machine and a leading American capitalist in Central America. As owner-editor of the New Orleans Times-Democrat and director general of the 1884 New Orleans world’s fair, Burke enjoyed a marvelous platform from which to broadcast his vision of a transnational New South that promoted Latin America as a market for southern-made exports and an investment opportunity for southern businessmen. The New Orleans exposition displayed technologies and products that shaped and at times threatened gender roles, racial hierarchies, class norms, local political dynamics, and imperial visions. Burke was also a key partner in the alliance between Louisiana’s Democratic government and the Louisiana lottery. The lottery, with its tentacles in Latin America and nearly every state of the Union, insured that no other Gilded Age political machine utilized national and transnational ties as successfully as Louisiana’s. In the late 1880s, Burke began a near forty-year residency in Honduras, where he held diversified interests in the country’s railroads and real estate along with substantial mineral concessions. The major also actively supported numerous Honduran administrations, held five different high-ranking positions in government-supported railroads, recruited other foreign capitalists, served as intermediary when disputes arose between capitalists and Honduran leaders, and informally advised several presidents on matters ranging from infrastructure projects to American politics. Using American and Latino perspectives, this study demonstrates how the interplay between the U.S. South and Latin America was a defining variable in their respective developments

Performance-Based Contracting for Rest Area Maintenance

To maintain rest area stops in the United States, three methods are used. They are the In-House method, Method-Based Contracting (MBC), and Performance-Based Contracting (PBC). In recent years, the PBC method has become increasingly popular because this method reduces the strain of managing In-House employees or MBC contracts, generates more business in the public sector, can increase the level of service (LOS), and generally reduces the costs of maintaining rest area stops up to 5%. In the United States, no less than 15 states use the PBC method to maintain their rest area stops, and the results from switching to this method of contracting has been beneficial. However, the Montana Department of Transportation (MDT) uses a combination of the In-House, MBC, and PBC methods to maintain rest area stops. The PBC method is only used at a small number of sites around the state. This research suggests that PBC would work well for maintaining all of Montana’s rest area stops. Unlike the In-House method and MBC, PBC is an output based method and uses Performance-Based Specification, which focuses on the output of the work performed (Stankevich et al., 2009). With this method, a contractor is selected using the ‘Best Value’ or ‘Qualification-Based’ methods. The PBC method also offers incentives and disincentives to the contractor that are tied with the work output (Popescu, and Monismith, 2006, and Schexnayder and Ohrn, 1997)

From Confederate Expatriates to New South Neo-Filibusters: Major Edward A. Burke and the Americas

The traditional historiography of the American South presents the New South creed as a vision emphasizing national reconciliation based upon the advancement of Southern commerce and industry. In addition, scholars broadly define New South spokesmen as men who came to maturity after the Civil War and did not involve themselves in state or national politics. An examination of Major Edward Austin Burke, however, reveals that at least one pivotal New South booster was a Confederate veteran and leading political figure; it also suggests the presence of an international component inherent in the New South paradigm of the 1880s. It is the argument of this thesis that increased commercial ties with the Americas was an inseparable part of the New South creed, and that this component was used as a fundamental means to reconcile North and South in imperial pursuits. This study analyzes Burke\u27s rise to Democratic party boss of Louisiana, his ascension as a leading New South spokesman, and his transformation into the embodiment of a commercial and industrial \u27neo-filibuster\u27 - defined here as New South ideologues who became the imperialist vanguard of an American, and not a partisan, South. The neo-filibusters were different from their antebellum forbears, but also different from Confederate expatriates who emigrated to Latin America immediately after defeat in the Civil War. Still, those expatriates who left the South after defeat are an effective counterpoint for later neo-filibusters. Those who impetuously left the South between April 1865 to December 1868 sought to live in isolation while endeavoring to reconstruct the Old South in a new environment. Despite their motivations, this work suggests that Confederate expatriates nonetheless strengthened the ties between the South and the Americas in important ways. The thesis also argues for a certain continuity of economic vision between the Old and New Souths. A significant number of antebellum Southerners, exemplified by J.D.B. DeBow, favored industrial pursuits, state activism and internal improvements. Their motivation for modernization, however, was to bolster the \u27peculiar institution\u27 of slavery and strengthen a regional way of life. New South spokesmen such as Burke shed the allegiance to slavery, which allowed for a nationally espoused ideal of Southern commercial and industrial progress. The examination of Burke\u27s residence in Honduras as a neo-filibuster from 1889 until his death in 1928 places the history of the American South in a broad international context. Instead of staging ersatz invasions or vainglorious coup d\u27Žtats, neo-filibusters like Burke were part of the larger nineteenth century international trend of imperialism - control through capital investment and exploitative political influence in underdeveloped countries

Market Bubbles and Wasteful Avoidance: Tax and Regulatory Constraints on Short Sales

Although short sales make an important contribution to financial markets, this transaction faces legal constraints that do not govern long positions. In evaluating these constraints, other commentators, who are virtually all economists, have not focused rigorously enough on the precise contours of current law. Some short sale constraints are mischaracterized, while others are omitted entirely. Likewise, the existing literature neglects many strategies in which well advised investors circumvent these constraints; this avoidance may reduce the impact of short sale constraints on market prices, but may contribute to social waste in other ways. To fill these gaps in the literature, this paper offers a careful look at current law and draws three conclusions. First, short sales play a valuable role in the financial markets; while there may be plausible reasons to regulate short sales-- most notably, concerns about market manipulation and panics -- current law is very poorly tailored to these goals. Second, investor self-help can ease some of the harm from this poor tailoring, but at a cost. Third, relatively straightforward reforms can eliminate the need for self-help while accommodating legitimate regulatory goals. In making these points, we focus primarily on a burden that other commentators have neglected: profits from short sales generally are ineligible for the reduced tax rate on long-term capital gains, even if the short sale is in place for more than one year.Short sales, Momentum traders, Value investors