Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The New Urban Agenda agreed upon at Habitat III highlights the need to redefine public policies for Latin American cities. One of the main topics of discussion is linked to the problem of access to land. In this framework, the Urban Prosperity Index gains importance by incorporating housing indicators aimed at urban sustainability. However, it does not include the land component and qualitative criteria that would allow, from a rights-based perspective, to make diagnosis and urban intervention more complex. This paper elaborates upon the proposal of construction of housing indicators by defining principles and useful criteria to monitor compliance with public policies.

In this article I present theoretical and methodological reflections on the study of the production and circulation of scientific knowledge. The proposal is derived from an investigation of my authorship where I reconstructed the evolution of the Andean ethnohistory between 1970 and 2005. I describe the approach and the materials used, indicating the main challenges that emerged in the construction of the object and the research problem. I develop the strategies implemented and I argue that their relevance transcends the case study. I present the results obtained and then the lines of research that are opened from them.

The procedure of analysis developed in the course of research on the concept of development in Buenos Aires social programs is presented. The general design of the aforementioned research is presented briefly as a context, including objectives, units of analysis, corpus characteristics and theoretical-methodological framework. Following a detailed description of the analytical procedures are given in its three moments: data reduction, construction of theoretical concepts through the aggregation of codes and comparison of findings through the units of analysis. It is suggested that the approach and procedure described above may be useful in other public policy studies.

The concern to understand the processes of political subjectivation that arise in the heat of contemporary social movements has generated debates in which different theoretical, epistemological and methodological traditions are discussed. In this article we review the contributions of authors inserted in critical currents with the intention of building tools that guide the methodological approach of subjectivities that emerge around concrete experiences of action and labour organization. Finally, these proposals are analyzed considering an empirical research carried out in Mexico City.

The article supports the viability of the use of modeling as a method of scientific knowledge within the Social Sciences and, in particular, its application to the study of communicative media processes. It defines modeling with its epistemological advantages and risks, to then expose the steps followed in the analysis of local coverage television in Cuba and the creation of a model that makes it possible to explain the operation of this system as well as its unexplored potentials to act in for the local development. They are used as fundamental techniques to arrive at knowledge documentary bibliographic research, interview, survey and constant triangulation, always marked by the patterns of modeling as a scientific method. The results open the way for a projective television proposal for local development in the Cuban context.

A precise orthometric height (H) and orthometric height difference (ΔH) determination is required in many fields like construction, geodesy and geophysics. H is often obtained from an ellipsoidal height (h) and geoid height (N) of a geoid model (GM) because this computation does not have the spirit leveling restrictions on long distances. However, the H accuracy depends on the GM local area adaptation, and current global geoid models (GGMs) have not been yet evaluated for Costa Rica. Therefore, this paper aims to determine which GGM maintains a better fit with a GPS/levelling baseline that contains the gravity full spectrum. A 74 km baseline was measured using GPS, spirit leveling and gravity measurements to validate the N computed from EGM2008, EIGEN-6C4, GECO, EGM96, GGM05C and GOCO05C. First, an absolute N assessment was made, where geoid height from the GGMs (NGGM) were directly compared to the geometric geoid heights (Ngeo) obtained from GPS and spirit levelling. A bias fit (Nbias) of about 2 m was computed from this comparison for most GGMs with respect to the local vertical reference surface (W0). By subtracting the Nbias, a relative geoid height (ΔN) assessment was designed to compare the differences between GGM relative geoid height (ΔNGGM) and geometric relative geoid height (ΔNgeo) on segments along the baseline. The ΔN comparison shows that EGM2008, EIGEN-6C4 and GECO better represent the Costa Rican Central Pacific Coastal Zone and over long distances, ΔH can be computed with a decimeter to centimeter precision.

An analytical, clear, accurate and explicit method to implement tilt correction, described in the ISO 12917:2017 standard for calibration of horizontal cylindrical tanks, is presented.  The method is superior to the graphical method proposed in the standard up to 2017 and improves the one proposed in the current standard.  Several of the difficulties presented by the correction method of the standard are discussed and clarified.  As a novel contribution, two numerical tables were produced with tilt correction values, equivalent to Figure A-1 of ISO 12917:2002 and which have not been previously reported.

The finite element method (FEM) is a numerical technique that estimates solutions of partial differential equations on arbitrary domains. It has been widely used to solve problems in physics and engineering. In general, the final step of this technique consists of a linear system of equations  in which the matrix  is sparse and its bandwidth depends on the finite element shape functions support. When the number of elements is large, even the efficient data structure sparse matrix representations can consume the entire computer memory. In this article, we describe a technique to solve these large-scale problems without explicitly representing this matrix. This computational trick is known as EBE (Element By Element). We also describe an application in which such kind of implementation is necessary, in the field of digital rock physics, to estimate the elastic coefficient of rock samples using micro-tomographic images.

The wave reanalysis is a important information source to develop research projects related to wave climate and coastal engineering applications. This information source is more relevant in places where it lacks historical registers coming from instrumental measurements as well as happens in Costa Rica. However, as the wave reanalysis is generated from a numerical model, it has been shown that it needs to be calibrated and validated with instrumental measurement. This work has used the wave reanalysis's node coming from NOAA in front of Cariben's Costa Rica coast, This information has been calibrated and validated with a buoy information. The product is a wave data base calibrated from 2005 onwards, which it is monthly updated; this information could be used in many coastal engineering applications and in wave climate variability analysis approximations.

This research provides the dynamic analysis of a distillation train, which instead of the traditional study of a binary mixture, this was carried out for a multicomponent mixture of the solvent recovery area of ​​a linear polyethylene plant. This was done through a dynamic simulation in Aspen Plus® with the purpose of predicting the behavior of the operational variables (temperature, pressure, flow, level or composition) when an interruption of the feed flow occurs in the distillation area to model a reaction area shutdown, and then establish procedures that compensate for deviations in the controlled variables. Several thermodynamic methods were evaluated: Soave-Redlich-Kwong, Peng-Robinson, Lee-Kesler-Plock, Peng-Robinson-Boston-Mathias y Soave-Redlich-Kwong-Boston-Mathias; the SRKBM method was chosen, since it presents lower error percentages in most of the estimated properties. This rigorous comparison adds greater reliability to the values reported in the simulations. The results showed a destabilization of the level controllers of distillation columns A and B, in addition to an increase of approximately 14 ° C in the temperature profile of column A. Column C did not show deviations from its operational variables. Finally, to stabilize the system, it was necessary to carry out three steps involving the switch to manual mode and changing the valve opening percentage of the column A steam flow controller (50%), the D-101separator pressure (50%) and the column B top flow controller (43%).