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En el presente documento se analiza la relación entre el precio de mercado y el valor catastral de los lotes baldíos, urbanizados y de propiedad horizontal, y su distribución espacial dentro del área urbana de la ciudad de Cuenca, con una superficie aproximada de 74 km2. El valor catastral de los lotes se obtuvo del portal del Gobierno Municipal Autónomo Descentralizado del Cantón Cuenca. Mientras que el precio de mercado se consiguió de las ofertas inmobiliarias publicadas en el período septiembre 2019 a marzo de 2020. De los 100,203 lotes, dentro del área de estudio, 994 lotes, de los cuales se encuentran disponibles el precio de mercado y el valor catastral, fueron incluidos en el estudio. En total, se utilizaron en el análisis 421 lotes sin construir, 518 parcelas construidas y 55 propiedades horizontales. El precio del suelo según la tasación municipal equivale, en promedio, al 54.15% del precio de mercado, lo que demuestra que el valor catastral de las propiedades está subvalorado. La autocorrelación espacial entre el precio de mercado y el valor catastral se derivó utilizando las estadísticas I de Moran y Gi*. Se determinaron lotes con precio de mercado alto con respecto al valor catastral, el 5% de los predios mostraron valores superiores al 4.82 con un máximo de 11.39. Considerando estos aspectos, los municipios, dado que la sociedad cambia a un ritmo acelerado, deben modernizar y renovar el sistema catastral, que tradicionalmente se considera que funciona bien, pero en muchos casos está desactualizado.

In this study soil parameters are back analyzed by using the finite element method and two optimization algorithms, the Non Linear Least Squares (NLLS) and Coupled Local Minimizers (CLM) method. Soil permeability parameters are back analyzed to match the observed values of the variation of pore-water pressures at the Fosso S. Martino Landslide in Italy. Piezometer readings are used to back analyze the permeability coefficients of three soil layers and the left-hand side water level boundary. Furthermore, the performance of each piezometer is evaluated through neglecting the information of other points and performing the optimization analysis. It is found that both optimization algorithms determine soil parameters that represent the pore-water fluctuation of the study area, with their advantages and drawbacks. The NLLS computes values that represent the performance of the pore-water fluctuation in the piezometer readings however, the selection of the starting values is important in order to reduce the computational time. The CLM method was also able to compute adequate soil parameters however, the computational effort is much higher due to the fact that this method uses several search points in the process. For the minimum monitoring setup needed for the adequate determination of soil parameters, the piezometers in the middle of the slope provided the best information. These piezometers are essential to adequately back analyze the soil properties in this case study. Great attention has to be considered in maintain these piezometers in order to continue monitoring the slope.

Highways have been and are built using Hot Mix Asphalt (HMA) as surface layer. The most common HMA design procedure is the Marshall Method, a method also used for quality control (QC) at the time of road construction. Due to several factors, sometimes it is not possible to sample the surface layer when constructed. When this occurs, QC is performed after construction by analyzing cores. Current regulations, however, fail having clear procedures regarding the collection and analysis of pavement cores after the complete placement of the asphalt mixture. For this reason, this study proposes a comparative analysis of Marshall parameters, mixture densities, and aggregates gradation obtained from specimens obtained during construction, versus cores samples extracted 30 and 60 days later. The research revealed that all the parameters measured on core samples, except flow, could be used to approve asphalt paving works after its construction.

This article reports on a comparative study between the publication productivity of Ecuador’s leading Higher Education Institutions (HEIs) (as reported in the SCOPUS journal/proceedings database; https://www.elsevier.com/solutions/scopus) and the publication efforts of similar universities in South-America and Western Europe when those universities converted from a “teaching-only” to a “teaching and research” focus. The authors highlight the causes of Ecuador’s research and publication paucity and suggest remedial strategies which focus on adjusting the profile and activities of Ecuador’s HEIs to better meet the skills gap in the 21st century economy; economy driven by innovation and knowledge. The article proposes that Ecuador’s HEIs make teaching collaborative and more affordable, stimulate faculty to examine society-relevant problems in teams, educate and encourage faculty to publish in peer-reviewed journals and enhance effectiveness and efficiency so that a stronger teaching-research-service nexus emerges; all even though Ecuador has entered a period of economic hardship with dwindling funds for higher education. Keywords : Ecuador, Higher Education Institutes, publication visibility, causal factors, remedial actions. RESUMEN Este articulo reporta un estudio comparativo entre el producto de publicaciones cientificas de las principales Instituciones de Educacion Superior (IES) en Ecuador (tal como se indica en la base de datos de revistas/actas de SCOPUS; https://www.elsevier.com/solutions/scopus) con el record de publicaciones de Universidades en America del Sur y Europa Occidental cuando estas cambiaron de un enfoque de “ensenanza” hacia uno de “ensenanza e investigacion”. Los autores discuten las causas del bajo nivel de investigacion y el reducido numero de publicaciones en las IES ecuatorianas; y proponen estrategias correctivas para ajustar el perfil y las actividades de las IES del Ecuador con el objeto de contrarrestar el deficit de habilidades necesarias para impulsar la economia del siglo XXI; economia impulsada por la innovacion y el conocimiento. El articulo propone que es necesario que las IES ecuatorianas faciliten el aprendizaje colaborativo y flexible, que aliente a los profesores a formar equipos de trabajo para examinar e investigar los problemas relevantes de la sociedad; ademas, de incentivar que estos difundan los resultados de sus investigaciones en revistas con revision por pares; de este modo, se lograra mejorar la eficacia y la eficiencia de las IES ecuatorianas al crear un nexo fuerte entre ensenanza-investigacion-vinculacion. Labor indispensable, a pesar de que Ecuador ha entrado en un periodo de dificultades economicas con la subsecuente disminucion de los fondos para la educacion superior. Palabras clave : Ecuador, Institutos de Educacion Superior, visibilidad de la publicacion, factores causales, acciones correctivas.

RESUMEN En este documento se analiza la factibilidad y eficiencia de la deflectometria de impacto para evaluar la capacidad portante de la estructura de un pavimento flexible en vias locales de la red austral E40. Mediante el equipo no destructivo conocido como deflectometro de impacto se generan deflexiones en el pavimento, las que son interpretadas a traves de tecnicas basadas en analisis inverso como AASHTO 93, LUKANEN, YONAPAVE y ROHDE. Dichas tecnicas permiten la cuantificacion y cualificacion del nivel de deterioro estructural del sistema pavimento-subrasante a traves de dos parametros. El primer parametro se define mediante el modulo resiliente, el cual es comparado con los softwares EVERCALC y ANSYS, que sustentan su desarrollo en analisis inverso y elementos finitos respectivamente. Por otro lado, el segundo parametro se define mediante la capacidad estructural del sistema pavimento-subrasante, el cual es analizado a traves del concepto de deflexion caracteristica propuesto por la guia de diseno AASHTO 93. EL estudio da a conocer que el mejor metodo para caracterizar el estado del pavimento es la tecnica propuesta por YONAPAVE. El documento no solo presenta resultados de la condicion actual de la via bajo estudio sino tambien proporciona recomendaciones con respecto al manejo del pavimento de la via, que permitan transformar la ingenieria de pavimentos a una ingenieria de gestion de los pavimentos. Palabras clave: Tecnica de auscultacion, deflexion, analisis inverso, ANSYS, EVERCALC, elementos finitos. ABSTRACT The feasibility and efficiency of impact deflectometry, to assess the structural capacity of flexible pavements on local roads of the southern E40 road network, were analyzed. Deflections generated by the impact of the non-destructive Falling Weight Deflectometer are interpreted using back-calculation techniques, such as proposed by AASHTO 93, LUKANEN, YONAPAVE and ROHDE. Those techniques enable the quantification and qualification of the structural deterioration level of existing pavement-subgrade systems by two parameters. The first parameter is derived from the resilient modulus, and its value is compared to the output of inverse and finite element analysis using respectively the EVERCALC and ANSYS software. The second parameter is defined by the structural capacity of the pavement-subgrade system, and derived applying the concept of characteristic deflection as described in the AASHTO Design Guide 93. The study revealed that the best method to characterize the road status is the analysis technique proposed by YONAPAVE. The approach not only presents results of the current condition of the road under study, but provides also recommendations regarding the management of road pavement. The developed methodology enables to elevate in future pavement engineering to pavement management engineering. Keywords: Auscultation techniques, deflection, back-calculation, ANSYS, EVERCALC, finite element.

This paper derives the best location of field sensor for landslide monitoring based on static, pseudostatic and dynamic finite element slope stability analysis. Use is made of the finite element technique as not to constrain the analysis by the assumptions required in classical approaches. Numerical techniques in general, easily handle the strain-stress relationship, the non-linear soil behaviour, and complex geometries. The present methodology is implemented in a potential landslide site at km 27 along the Cuenca-Machala highway, Ecuador. This site has a cut slope of about 40 degrees with a length of 130 m and it is 100 m wide, given an approximated landslide volume of 240,000 m 3 with an average depth of 18.5 m. The soils behaviour is represented as elastic-plastic soil material with a Mohr-Coulomb failure criterion for which the soil strength parameters were derived from in-situ and laboratory tests. The changes of static and/or dynamic stresses, geometry and soil properties will cause a variation where the highest displacements are developed. The location of the highest total, vertical and horizontal displacements are used to judge the best location for installing sensors for landslide monitoring. Different scenarios are analyzed to evaluate the effect of introducing remedial measures and different transient conditions. The results of the numerical simulation enabled definition of the most efficient and cost-effective location of the sensors to alert for potential landslides.