Stochastic Satbility and Performance Robustness of Linear Multivariable Systems

Stochastic robustness, a simple technique used to estimate the robustness of linear, time invariant systems, is applied to a single-link robot arm control system. Concepts behind stochastic stability robustness are extended to systems with estimators and to stochastic performance robustness. Stochastic performance robustness measures based on classical design specifications are introduced, and the relationship between stochastic robustness measures and control system design parameters are discussed. The application of stochastic performance robustness, and the relationship between performance objectives and design parameters are demonstrated by means of example. The results prove stochastic robustness to be a good overall robustness analysis method that can relate robustness characteristics to control system design parameters

Falling Behind: Americans' Access to Medical Care Deteriorates, 2003-2007

Presents survey results on access to medical care for the insured and the uninsured, the healthy and the ill, and for children in wealthy and poor families. Discusses causes of unmet needs such as rising costs and obstacles in the health system and plans

More Nonelderly Americans Face Problems Affording Prescription Drugs

Analyzes 2003-07 trends in unmet prescription drug needs among Americans under age 65 by insurance status and type of coverage, income level, and the presence of chronic conditions. Explores implications of the economic downturn and changes to Medicaid

Safety Net hospital Emergency Departments: Creating Safety Valves for Non-urgent Care

Outlines how safety-net hospitals are addressing the rise in emergency department visits for non-urgent care, such as re-directing patients to outpatient clinics or community health centers and adding primary care capacity. Discusses policy implications

Do Agglomeration Economies Exist in the Hospital Services Industry

Given the importance of knowledge flows and the continued emphasis on face-to-face encounters especially for medical care, close proximity of hospitals may be essential for the efficient delivery of medical care. That is, hospital productivity might be greater where hospitals cluster and allow knowledge to more easily and quickly disperse among personnel in the various organizations. To add to the understanding about agglomeration economies in the hospital services sector, this study analyzes how the clustering of hospitals in the various metropolitan areas of the US affects industry wide productivity. The multiple regression analysis is conducted on a cross-sectional basis for both 1993 and 1999 and by using first differencing of the data between the two years. The observed productivity improvements resulting from the clustering of hospitals provides yet another justification for encouraging a larger number of hospitals in metropolitan areas.

SOURCES OF PRODUCTIVITY GROWTH DURING THE TRANSITION TO ALTERNATIVE CROPPING SYSTEMS

Traditional measures of productivity growth may not fully account for all sources of growth during the transition from conventional to alternative cropping systems. This paper treats soil quality as part of the production process and incorporates it directly into rotational measures of productivity growth. An application to data from an experimental cropping system in Pennsylvania suggests that both experimental learning and soil-quality improvements were important sources of growth during the system's transition.Productivity Analysis,

We thought it might encourage participation.” Using lottery incentives to improve LibQUAL+(TM) response rates among students

Libraries deploying the LibQUAL+™ survey can offer a lottery incentive and many do in the hope of increasing response rates. Other libraries may be prohibited from offering one because of Institutional Review Board restrictions, as is the case at [institution name]. We wanted to discover why libraries offer lottery incentives and what kinds and if they believe these incentives have a positive impact on their response rates. The responding libraries hold a general belief that lottery incentives are effective but base this on feeling rather than research. We examine what the literature says about lottery incentives and student populations

Suburban Poverty and the Health Care Safety Net

Examines trends in the number of suburban poor, their access to health care, and efforts to improve safety-net services in the suburbs of five cities. Explores causes of limited safety net capacity, community strategies, and policy implications

The Incidence of Debris Disks at 24 {\mu}m and 670 Myr

We use Spitzer Space Telescope 24 {\mu}m data to search for debris disks among 122 AFGKM stars from the \sim 670 Myr clusters Hyades, Coma Ber, and Praesepe, utilizing a number of advances in data reduction and determining the intrinsic colors of main sequence stars. For our sample, the 1{\sigma} dispersion about the main sequence V-K, K-[24] locus is approximately 3.1%. We identify seven debris disks at 10% or more (\geq 3{\sigma} confidence level) above the expected K-[24] for purely photospheric emission. The incidence of excesses of 10% or greater in our sample at this age is 5.7 +3.1/-1.7%. Combining with results from the literature, the rate is 7.8 +4.2/-2.1% for early- type (B9 - F4) stars and 2.7 +3.3/-1.7% for solar-like (F5 - K9) stars. Our primary sample has strict criteria for inclusion to allow comparison with other work; when we relax these criteria, three additional debris disks are detected. They are all around stars of solar-like type and hence reinforce our conclusion that disks around such stars are still relatively common at 670 Myr and are similar to the rate around early-type stars. The apparently small difference in decay rates between early-type and solar-like stars is inconsistent with the first order theoretical predictions that the later type stellar disks would decay an order of magnitude more quickly than the earlier type ones.Comment: 26 pages, 3 figures, accepted for publication in Ap

Key Findings From HSC's 2010 Site Visits: Health Care Markets Weather Economic Downturn, Brace for Health Reform

Presents findings about hospital payment rate increases, hospital-physician alignment, and insurance premiums, funding for safety-net providers, and their implications from HSC's site visits to twelve nationally representative metropolitan communities