Using Discontinuous Eligibility Rules to Identify the Effects of the Federal Medicaid Expansions on Low Income Children

This paper exploits the discrete nature of the eligibility criteria for two major federal expansions of Medicaid to measure the effects on Medicaid coverage, overall health insurance coverage, and the probability of visiting a doctor. The '100 percent' expansion, effective in 1991, extended Medicaid eligibility to children born after September 30, 1983 in families below the poverty line. We estimate that this law led to about a 10 percentage point rise in Medicaid coverage for children born just after the cutoff date, and a similar or slightly smaller rise in overall health insurance. It also increased the fraction of children in the newly eligible group with a doctor visit in the previous year. The '133 percent' expansion, effective in 1990, extended Medicaid to children under 6 in families with incomes below 133 percent of the poverty line. This law had relatively small effects on Medicaid coverage for children near the eligibility limits, and little or no effect on health insurance coverage.

Using Discontinuous Eligibility Rules to Identify the Effects of the Federal Medicaid Expansions on Low Income Children

Despite intensive scrutiny, the effects of Medicaid expansions on the health insurance status of low-income children remain controversial. We re-examine the effects of the two largest federally-mandated expansions which offered Medicaid coverage to low-income children in specific age ranges and birth cohorts. We use a regression discontinuity approach, comparing Medicaid enrollment, private insurance coverage, and overall insurance coverage on either side of the age limits of the laws. We conclude that the modest impacts of the expansions on health insurance coverage arose because of very low takeup rates of the newly available coverage, rather than from crowd-out of private insurance coverage.

The French Economy, European Authorities, and the IMF: "Structural Reform" or Increasing Employment?

This paper looks at two competing views among economists and other observers, of how the French economy can overcome mass unemployment and have a more robust recovery. One view sees the unemployment and economic stagnation of the past decade as overwhelmingly structural. An alternative narrative, mostly from the Left but with some elements adopted by the far Right, sees the most immediate problem as one of inadequate demand in the economy.The authors find that France's unemployment rate, which has averaged 9.1 percent over the last decade, is not the product of "structural" barriers, but rather due to political choices made by the French government and European authorities. With inflation well below target, real borrowing costs at about zero, and a low current interest burden on the debt, it would make much more economic sense for the government -- and the eurozone as well -- to pursue an expansionary fiscal policy that increases employment

An investigation of the Eigenvalue Calibration Method (ECM) using GASP for non-imaging and imaging detectors

Polarised light from astronomical targets can yield a wealth of information about their source radiation mechanisms, and about the geometry of the scattered light regions. Optical observations, of both the linear and circular polarisation components, have been impeded due to non-optimised instrumentation. The need for suitable observing conditions and the availability of luminous targets are also limiting factors. GASP uses division of amplitude polarimeter (DOAP) (Compain and Drevillon) to measure the four components of the Stokes vector simultaneously, which eliminates the constraints placed upon the need for moving parts during observation, and offers a real-time complete measurement of polarisation. Results from the GASP calibration are presented in this work for both a 1D detector system, and a pixel-by-pixel analysis on a 2D detector system. Following Compain et al. we use the Eigenvalue Calibration Method (ECM) to measure the polarimetric limitations of the instrument for each of the two systems. Consequently, the ECM is able to compensate for systematic errors introduced by the calibration optics, and it also accounts for all optical elements of the polarimeter in the output. Initial laboratory results of the ECM are presented, using APD detectors, where errors of 0.2% and 0.1{\deg} were measured for the degree of linear polarisation and polarisation angle respectively. Channel-to-channel image registration is an important aspect of 2-D polarimetry. We present our calibration results of the measured Mueller matrix of each sample, used by the ECM. A set of Zenith flat-field images were recorded during an observing campaign at the Palomar 200 inch telescope in November 2012. From these we show the polarimetric errors from the spatial polarimetry indicating both the stability and absolute accuracy of GASP.Comment: Accepted for publication in Experimental Astronom

The Measurement of Medicaid Coverage in the SIPP : Evidence from a Comparison of Matched Records

This paper studies the accuracy of reported Medicaid coverage in the Survey of Income and Program Participation (SIPP) using a unique data set formed by matching SIPP survey responses to administrative records from the State of California. Overall, we estimate that the SIPP underestimates Medicaid coverage in the California population by about 10 percent. The probability that a SIPP respondent who is covered by Medicaid in a given month correctly reports their coverage is around 85 percent. The corresponding probability for low-income children is higher – around 90 percent. Under-reporting by those who are actually in the Medicaid system is partially offset by over-reporting of coverage by people who are not. Some of these false positive responses are attributable to errors and missing data in the administrative system, rather than to problems in the SIPP. Taking account of these errors, the estimated false positive rate for the population as a whole is about 1.5 percent, and 4-5 percent for poor children.

RADIATION HEAT TRANSFER IN DIRECT-INJECTION DIESEL ENGINES

En las últimas décadas, la investigación en motores de combustión ha estado enfocada fundamentalmente en la reducción de las emisiones contaminantes y la eficiencia de los mismos. Estos hechos junto con un aumento de la concienciación sobre el cambio climático han llevado a un aumento en la importancia de la eficiencia térmica respecto a otros criterios en el diseño de motores de combustión interna (MCIA). Para alcanzar este objetivo, existen diferentes estrategias a aplicar. En concreto, la transferencia de calor a las paredes de la cámara de combustión puede ser considerada como una de las principales fuentes de disminución de la eficiencia indicada. En particular, en los modernos motores diésel de inyección directa, la emisión de radiación de las partículas de hollín puede constituir un componente importante de las pérdidas de eficiencia. En este contexto se enmarca el objetivo principal de la tesis: contribuir a la comprensión de la transferencia de calor por radiación en la combustión diésel de inyección directa junto con la mejora del conocimiento en el proceso de formación-oxidación de hollín. El trabajo se ha basado tanto en resultados experimentales mediante la aplicación de técnicas ópticas en diversas tipologías de motor como en resultados simulados a partir de modelos unidimensionales validados. En la primera parte de resultados experimentales, se ha evaluado la cantidad de energía por radiación respecto a la energía química del combustible mediante la aplicación de una sonda optoelectrónica (basada en la técnica del 2-Colores) tanto en un motor óptico DI como en motor poli-cilíndrico DI de producción. En este estudio se han obtenido valores de intensidad espectral emitida por el hollín y posteriormente, la radiación total emitida por las partículas de hollín en todo el espectro. Como se ha citado anteriormente, las partículas de hollín son las principales responsables de la transferencia de calor por radiación, además de uno de los principales agentes contaminantes emitidos por los motores diésel. Las emisiones de hollín son el resultado de dos procesos antagonistas: la formación y oxidación del hollín. Los mecanismos de formación de hollín se discuten extensamente en la literatura. Sin embargo, existen deficiencias en cuanto al conocimiento de la oxidación de hollín. Por lo tanto, el objetivo de esta sección ha sido evaluar el impacto del proceso de mezcla y la temperatura del gas sobre el proceso de oxidación de hollín durante la última parte de la combustión bajo condiciones reales de operación. Finalmente, y en base a los resultados y conocimientos adquiridos hasta el momento, se ha desarrollado un modelo capaz de predecir las pérdidas de calor por radiación para un chorro diésel. El modelo está basado en tres sub-modelos: modelo de chorro, el cual analiza y caracteriza la estructura interna del chorro en términos de mezcla y combustión en un proceso de inyección con resolución temporal y espacial. Un modelo de hollín, en el que los resultados se justifican en función de procesos de formación y oxidación del hollín. La cohesión de estos dos sub-modelos se utiliza para obtener los valores de entrada al modelo de radiación, con el que se obtiene los valores de transferencia de calor por radiación para una llama diésel.En els últims anys, la recerca en motors de combustió ha estat focalitzada principalment en la reducció de les emissions contaminants i la millora de la eficiència. Aquests fets afegits al fet del augment de la conscienciació del canvi climàtic han impulsat el interés per incrementar la eficiència tèrmica per damunt de altres criteris en el disseny de motors de combustió interna alternatius (MCIA). Per aconseguir aquest objectiu, existixen diferents estratègies a aplicar. Concretament, la transferència de calor a les parets de la càmera de combustió pot ser considerada un dels principals focs de reducció de eficiència indicada. En particular, en els moderns motors dièsel de injecció directa, la emissió de radiació de les partícules de sutja pot constituir un component important de les pèrdues de eficiència. En aquest context s'emmarca el objectiu principal de la tesis: contribuir a la comprensió de la transferència de calor per radiació en la combustió dièsel de injecció directa i la millora del coneixement del procés de formació-oxidació de la sutja. El treball esta basat tant en resultats experimentals mediant l'aplicació de tècniques òptiques en diverses tipologies de motor com en resultants simulats a partir de models unidimensionals validats. En la primera part dels resultats experimentals, s'ha avaluat la quantitat de energia per radiació respecte a la energia química del combustible mediant la aplicació de una sonda optoelectrònica (basada en la tècnica del 2-Colors) tant en un motor òptic DI com en un motor poli-cilíndric DI de producció en serie. En aquest estudi s'han obtingut valors de intensitat espectral emesa per la sutja i posteriorment, la radiació total emesa per les partícules de sutja en tot el espectre. Com s'ha citat amb anterioritat, les partícules de sutja son les principals responsables de la transferència de calor per radiació, a més de un del principals agents contaminants emès per els motors dièsel. Les emissions de sutja son el resultat de dos processos antagonistes: la formació i la oxidació de sutja. Els mecanismes de formació de sutja es discuteixen àmpliament en la literatura. No obstant això, existeixen deficiències pel que fa al coneixement de l'oxidació de sutja. Per tant, l'objectiu d'aquesta secció ha sigut avaluar l'impacte del procés de mescla i la temperatura del gas sobre el procés d'oxidació de sutja durant l'última part de la combustió sota condicions reals d'operació. Finalment, i en base als resultats i coneixements adquirits fins aquest moment, s'ha desenvolupat un model que permet predir les perdudes de calor però radiació per a un raig dièsel. El model esta basat en tres sub-models: model de raig, el qual analitza i caracteritza la estructura interna del raig en termes de mescla i combustió en un procés de injecció amb resolució temporal i espacial. Un model de sutja, en el qual els resultats es justifiquen en funció del procés de formació i oxidació de la sutja. La cohesió d'aquests dos sub-models s'utilitza per obtindre els valors d'entrada al model de radiació, amb el que s'obté els valors de transferència de calor per radiació per a una flama dièsel.In the last two decades engine research has been mainly focused on reducing pollutant emissions and increasing efficiency. These facts together with growing awareness about the impacts of climate change are leading to an increase in the importance of thermal efficiency over other criteria in the design of internal combustion engines (ICE). To achieve the objective, there are different strategies to apply. The heat transfer to the combustion chamber walls can be considered as one of the main sources of indicated efficiency diminution. In particular, in modern direct-injection diesel engines, the radiation emission from soot particles can constitute a significant component of the efficiency losses. In this context, the main objective of the thesis is framed: to contribute to the understanding of the radiation heat transfer in DI diesel combustion together with the improvement of the knowledge in the soot formation-oxidation processes. The work has been based on experimental results through the optical technique application in different types of engine and on simulated results from validated one-dimensional models. In the first part of experimental results, the amount of energy lost to soot radiation relative to the input fuel chemical energy has been evaluated by means of the optoelectronic probe application (based on the 2-Color technique) in both an optical engine DI and a production 4-cylinder DI engine. In this study, the values of soot spectral intensity emitted have been obtained and later, the total radiation emitted by the soot particles in the whole spectrum. As mentioned above, soot particles are the main responsible for the radiation heat transfer, in addition to one of the important concern in meeting emissions regulations. Soot emissions are the result of two competing processes: soot formation and soot oxidation. Mechanisms of soot formation are discussed extensively in the literature. However, there are deficiencies in the knowledge of soot oxidation. Therefore, the objective of this section has been to evaluate the impact of mixing process and bulk gas temperature on late-cycle soot oxidation process under real operating conditions. Finally, based on the results and knowledge acquired, a model able to predict heat losses by radiation for a spray diesel has been developed. The model is based on three sub-models: spray model, which analyzes and characterizes the internal spray structure in terms of mixing and combustion process with temporal and spatial resolution. A soot model, in which the results have been justified according to soot formation and oxidation processes. The link of these two sub-models has been used to obtain the input values to the radiation model, which the radiation heat transfer values for a diesel flame are obtained.Villalta Lara, D. (2018). RADIATION HEAT TRANSFER IN DIRECT-INJECTION DIESEL ENGINES [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/114793TESI