5,520 research outputs found
Sampling international migrants with origin-based snowballing method:
This paper provides a methodological assessment of the advantages and drawbacks of the origin-based snowballing technique as a reliable method to construct representative samples of international migrants in destination areas. Using data from the MAFE-Senegal Project, our results indicate that this is a very risky method in terms of quantitative success. Besides, it implies some clear selection biases: it over-represents migrants more strongly connected to their home country, and it tends to overestimate both poverty in households at origin and the influence of previous migration experiences of social networks on individuals’ out-migration.international migration, sample, survey methodology
Climate engineering by enhancement of ocean alkalinity: impacts on the Earth system and a comparison with solar radiation management
An agenda to debate: The world bank group’s climate change and rural development plans for Argentina
En este trabajo se propone analizar la agenda del Grupo Banco Mundial (GBM) sobre cambio climático y desarrollo rural de la Argentina. Primero, observamos cómo el GBM ha consolidado una estrategia (ideológica, política y financiera) que promueve desarrollo sostenible como solución a la crisis ambiental global.
Observamos tres mecanismos de acción: mercado, ecotecnocracia y descentralización estatal. Posteriormente, se analizan las estrategias
frente al cambio climático y cómo este mantiene coherencia y se articula con los esquemas propuestos desde 1992. En la última parte se abordan las propuestas del GBM para la Argentina y sus implicaciones en la agenda de desarrollo del país. Se observa que el cambio climático es utilizado como un marco de justi-ficación para impulsar soluciones neoliberales (verdes) frente a los problemas socioambientales
rurales del país. Para efectuar el análisis se trabajó sobre fuentes documentales, se llevó el seguimiento de la agenda del GBM en su página web durante el período 2015-2016 y se utilizó bibliografía especializada para abordar las interpretaciones.This article aims to analyze the agenda of the World Bank Group (WBG) on climate change and rural development in Argentina. First, we observe how the WBG has consolidated a strategy (ideological, political and financial) that promotes sustainable development as a solution for the global environmental crisis. We observe three mechanisms of action: market, ecotechnocracy and state decentralization.
Second, we analyze strategies against climate change and how they are coherent
and articulated with the schemes proposed since 1992. The last part of the study addresses the proposals of the WBG for Argentina and their implications in the agenda for the development of the country. In order to carry out the analysis, documents were examined, the EBG agenda was tracked on its website during
2015-2016 and specialized bibliography was used to adopt interpretations.Fil: Ferrer Gonzalez, César Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Ciencias Humanas, Sociales y Ambientales; Argentin
Impacts of artificial ocean alkalinization on the carbon cycle and climate in Earth system simulations
Using the state-of-the-art emissions-driven Max-Planck-Institute Earth system model, we explore the impacts of artificial ocean alkalinization (AOA) with a scenario based on the Representative Concentration Pathway (RCP) framework. Addition of 114 Pmol of alkalinity to the surface ocean stabilizes atmospheric CO2 concentration to RCP4.5 levels under RCP8.5 emissions. This scenario removes 940 GtC from the atmosphere and mitigates 1.5 K of global warming within this century. The climate adjusts to the lower CO2 concentration preventing the loss of sea-ice and high sea level rise. Seawater pH and the carbonate saturation state (Ω) rise substantially above levels of the current decade. Pronounced differences in regional sensitivities to AOA are projected, with the Arctic Ocean and tropical oceans emerging as hot spots for biogeochemical changes induced by AOA. Thus, the CO2 mitigation potential of AOA comes at a price of an unprecedented ocean biogeochemistry perturbation with unknown ecological consequences
Creative Collaboration: Providing Inclusive Access to FIU Libraries\u27 Collections
The FIU Libraries Special Collections and Cataloging departments are immersed in a project to make primary source materials more accessible to the South Florida community and internationally. This presentation will demonstrate how archivists and catalogers worked collaboratively to provide access by leveraging traditional approaches and new tools to increase discoverability in Finding Aids and the library catalog.
Throughout the years, the archives at FIU Libraries has collected historical records that represent the history of the Hispanic community in Miami. Although Miami is known as having a large Hispanic community, the discovery of collection material represents a challenge for non-English speakers which has led to the under use of collection materials. The archivists and catalogers have identified language as one of the barriers in locating materials in the Finding Aids. As part of the FIU Libraries larger initiative to provide equitable access to our collections, the Special Collections and Cataloging departments have decided to enhance access to collections using the original language of the community documented in addition to English. We will discuss our processes working with specific collections to provide bi-language description, multiple points of access, and full text transcription
Quantum Criticality and Superconductivity in Quasi-Two-Dimensional Dirac Electronic Systems
We present a theory describing the superconducting (SC) interaction of Dirac
electrons in a quasi-two-dimensional system consisting of a stack of N planes.
The occurrence of a SC phase is investigated both at T=0 and T\neq 0, in the
case of a local interaction, when the theory must be renormalized and also in
the situation where a natural physical cutoff is present in the system. In both
cases, at T=0, we find a quantum phase transition connecting the normal and SC
phases at a certain critical coupling. The phase structure is shown to be
robust against quantum fluctuations. The SC gap is determined for T=0 and T\neq
0, both with and without a physical cutoff and the interplay between the gap
and the SC order parameter is discussed. Our theory qualitatively reproduces
the SC phase transition occurring in the underdoped regime of the high-Tc
cuprates. This fact points to the possible relevance of Dirac electrons in the
mechanism of high-Tc superconductivity.Comment: To be published in Nuclear Physics, Section B. 24 pages, 4 figure
Direct and adjoint global stability analysis of turbulent transonic flows over a NACA0012 profile
In this work, various turbulent solutions of the two-dimensional (2D) and three-dimensional compressible Reynolds averaged Navier?Stokes equations are analyzed using global stability theory. This analysis is motivated by the onset of flow unsteadiness (Hopf bifurcation) for transonic buffet conditions where moderately high Reynolds numbers and compressible effects must be considered. The buffet phenomenon involves a complex interaction between the separated flow and a shock wave. The efficient numerical methodology presented in this paper predicts the critical parameters, namely, the angle of attack and Mach and Reynolds numbers beyond which the onset of flow unsteadiness appears. The geometry, a NACA0012 profile, and flow parameters selected reproduce situations of practical interest for aeronautical applications.
The numerical computation is performed in three steps. First, a steady baseflow solution is obtained; second, the Jacobian matrix for the RANS equations based on a finite volume discretization is computed; and finally, the generalized eigenvalue problem is derived when the baseflow is linearly perturbed. The methodology is validated predicting the 2D Hopf bifurcation for a circular cylinder under laminar flow condition. This benchmark shows good agreement with the previous published computations and experimental data.
In the transonic buffet case, the baseflow is computed using the Spalart?Allmaras turbulence model and represents a mean flow where the high frequency content and length scales of the order of the shear-layer thickness have been averaged. The lower frequency content is assumed to be decoupled from the high frequencies, thus allowing a stability analysis to be performed on the low frequency range. In addition, results of the corresponding adjoint problem and the sensitivity map are provided for the first time for the buffet problem. Finally, an extruded three-dimensional geometry of the NACA0012 airfoil, where all velocity components are considered, was also analyzed as a Triglobal stability case, and the outcoming results were compared to the previous 2D limited model, confirming that the buffet onset is well detected
- …