Unveiling the Sigma-Discrepancy in IR-Luminous Mergers I: Dust & Dynamics

Mergers in the local universe present a unique opportunity for studying the transformations of galaxies in detail. Presented here are recent results, based on multi-wavelength, high-resolution imaging and medium resolution spectroscopy, which demonstrate how star-formation and the presence of Red Supergiants and/or Asymptotic Giant Branch stars has lead to a serious underestimation of the dynamical masses of infrared-bright galaxies. The dominance of a nuclear disk of young stars in the near-infrared bands, where dust obscuration does not block their signatures, can severely bias the global properties measured in a galaxy, including mass. This explains why past studies of gas-rich Luminous & Ultraluminous Infrared Galaxies, which have measured dynamical masses using the 1.62 or 2.29 micron CO band-heads, have found that these galaxies are forming m < m* ellipticals. On the other hand, precisely because of dust obscuration, I-band photometry and central velocity dispersions obtained with the Calcium II triplet at 0.85 microns reflect the global properties of the mergers and suggest that all types of merger remnants, including infrared-bright ones, will form m > m* ellipticals. Moreover, merger remnants, including LIRGs, are placed on the I-band Fundamental Plane for the first time and appear to be virtually indistinguishable from elliptical galaxies.Comment: Accepted for publication in The Astrophysical Journal, to appear Feb 20, 2010 v710. 82 pages, 19 Figures, 2 Appendices Minor update to reference

Central Bank Transparency and Nonlinear Learning Dynamics

Central bank communication plays an important role in shaping market participants' expectations. This paper studies a simple nonlinear model of monetary policy in which agents have incomplete information about the economic environment. It shows that agents' learning and the dynamics of the economy are heavily affected by central bank transparency about its policy rule. A central bank that does not communicate its rule can induce 'learning equilibria' in which the economy alternates between periods of deflation coupled with low output and periods of high economic activity with excessive inflation. More generally, initial beliefs that are arbitrarily close to the inflation target equilibrium can result in complex economic dynamics, resulting in welfare-reducing fluctuations. On the contrary, central bank communication of policy rules helps stabilize expectations around the inflation target equilibrium

Diseño de stands para ferias itinerantes en la ciudad de Ambato

1. Tema y planteamiento del problema. 2. Antecedentes investigativos. 3. Metodología. 4. PropuestaLa ciudad de Ambato funciona como centro de comercialización de toda la provinvia; esta actividad se ha desarrollado tanto, que no solo se negocia en los espacios designados para ello, sino que se ha invadido, parques, veredas, portones y calles de la ciudad, convirtiendose en verdaderas ferias libres. La informalidad en la ciudad de Ambato, debe ser contextualizado como un proceso administrativo que tiene raíces históricas culturales, que a la vez, interacciona de una forma dinámica con los hechos contemporáneos, operando de manera local y nacional. Es importante acotar que toda esta informalidad tiene sus ventajas y desventajas, una ventaja es que atraen a grandes cantidades de vendedores y compradores, lo que permite que se comercialice importantes cantidades de productos en pocas horas; y entre las desventajas se puede señalar la difucultad qye se ocasiona para el normal desarrollo del tránsito, de peatones, de ofertantes y demantantes. Por lo tanto este proyecto busca pretender normar de cierta manera la mala ubicación de los feriantes y proveer mobiliario específico para la realización de las feriasPontificia Universidad Católica del Ecuador, Escuela de Diseño IndustrialIngeniero en Diseño Industria

Valuing year-to-go hydrologic forecast improvements for a peaking hydropower system in the Sierra Nevada

We assessed the potential value of hydrologic forecasting improvements for a snow-dominated high-elevation hydropower system in the Sierra Nevada of California, using a hydropower optimization model. To mimic different forecasting skill levels for inflow time series, rest-of-year inflows from regression-based forecasts were blended in different proportions with representative inflows from a spatially distributed hydrologic model. The statistical approach mimics the simpler, historical forecasting approach that is still widely used. Revenue was calculated using historical electricity prices, with perfect price foresight assumed. With current infrastructure and operations, perfect hydrologic forecasts increased annual hydropower revenue by $0.14 to$1.6 million, with lower values in dry years and higher values in wet years, or about $0.8 million (1.2%) on average, representing overall willingness-to-pay for perfect information. A second sensitivity analysis found a wider range of annual revenue gain or loss using different skill levels in snow measurement in the regression-based forecast, mimicking expected declines in skill as the climate warms and historical snow measurements no longer represent current conditions. The value of perfect forecasts was insensitive to storage capacity for small and large reservoirs, relative to average inflow, and modestly sensitive to storage capacity with medium (current) reservoir storage. The value of forecasts was highly sensitive to powerhouse capacity, particularly for the range of capacities in the northern Sierra Nevada. The approach can be extended to multireservoir, multipurpose systems to help guide investments in forecasting