A highly efficient engineering tool for three-dimensional scramjet flowfield and heat transfer computations

The SIMPLE-based parabolic flow code, SHIP3D, was under development for use as a parametric design and analysis tool for scramjets. Some capabilities and applications of the code are demonstrated, and a report on its current status is given. The focus is on the combustor for which the code was mostly used. Recently, it was also applied to nozzle flows. Code validation results are presented for combustor unit problems involving film cooling, transverse fuel injection, and nozzle test. A parametric study of a film cooled or transpiration cooled Mach 16 combustor is also conducted to illustrate the application of the code to a design problem

Your community gets a B-: analysis of the specific and curious realm of airport bond rating

Commercial airports are publicly-owned transportation infrastructure, usually funded with bonds. The bond rating decision for these entities thus has important ramifications for bond investors, issuers, airport managers, and even the communities the airports serve, but the rating decision process is not well understood. This paper discusses a simulation of the rating process in two decision environments, including a downgrade. The effect of information framing in an environment of incomplete data is examined using amateur evaluators. Amateur evaluators were utilized to understand how people with limited financial analysis skills would respond when presented with incomplete information and a primed scenario. The results indicate that amateur evaluators were more likely to downgrade a bond grade than a ratings agency, but this effect was moderated for amateur evaluators with more work experience. Implications for airport and supply chain infrastructure are discussed

Using Microsimulation Models for Revenue Forecasting in Developing Countries

The use of microsimulation models for revenue forecasting in developing countries is addressed and contrasted to some of the alternative forecasting techniques. Given the problems of many of the alternative techniques, microsimulation models are often found to be the preferred revenue estimation method. The microsimulation revenue estimation is illustrated with data for the Jamaican personal income tax. Details for the example related to the data requirements, problems, and the necessary assumptions for obtaining revenue estimates are discussed and several alternate tax policy changes are simulated and presented

The grounded psychometric development and initial validation of the Health Literacy Questionnaire (HLQ)

BACKGROUND: Health literacy has become an increasingly important concept in public health. We sought to develop a comprehensive measure of health literacy capable of diagnosing health literacy needs across individuals and organisations by utilizing perspectives from the general population, patients, practitioners and policymakers. METHODS: Using a validity-driven approach we undertook grounded consultations (workshops and interviews) to identify broad conceptually distinct domains. Questionnaire items were developed directly from the consultation data following a strict process aiming to capture the full range of experiences of people currently engaged in healthcare through to people in the general population. Psychometric analyses included confirmatory factor analysis (CFA) and item response theory. Cognitive interviews were used to ensure questions were understood as intended. Items were initially tested in a calibration sample from community health, home care and hospital settings (N=634) and then in a replication sample (N=405) comprising recent emergency department attendees. RESULTS: Initially 91 items were generated across 6 scales with agree/disagree response options and 5 scales with difficulty in undertaking tasks response options. Cognitive testing revealed that most items were well understood and only some minor re-wording was required. Psychometric testing of the calibration sample identified 34 poorly performing or conceptually redundant items and they were removed resulting in 10 scales. These were then tested in a replication sample and refined to yield 9 final scales comprising 44 items. A 9-factor CFA model was fitted to these items with no cross-loadings or correlated residuals allowed. Given the very restricted nature of the model, the fit was quite satisfactory: χ(2)(WLSMV)(866 d.f.) = 2927, p<0.000, CFI = 0.936, TLI = 0.930, RMSEA = 0.076, and WRMR = 1.698. Final scales included: Feeling understood and supported by healthcare providers; Having sufficient information to manage my health; Actively managing my health; Social support for health; Appraisal of health information; Ability to actively engage with healthcare providers; Navigating the healthcare system; Ability to find good health information; and Understand health information well enough to know what to do. CONCLUSIONS: The HLQ covers 9 conceptually distinct areas of health literacy to assess the needs and challenges of a wide range of people and organisations. Given the validity-driven approach, the HLQ is likely to be useful in surveys, intervention evaluation, and studies of the needs and capabilities of individuals