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- PublicationStabilised finite element methods for a bending moment formulation of the Reissner-Mindlin plate modelThis work presents new stabilised finite element methods for a bending moments formulation of the Reissner-Mindlin plate model. The introduction of the bending moment as an extra unknown leads to a new weak formulation, where the symmetry of this variable is imposed strongly in the space. This weak problem is proved to be well-posed, and stabilised Galerkin schemes for its discretisation are presented and analysed. The finite element methods are such that the bending moment tensor is sought in a finite element space constituted of piecewise linear continuos and symmetric tensors. Optimal error estimates are proved, and these findings are illustrated by representative numerical experiments.
- PublicationVariation in habitat use along the freshwater-marine continuum by grey mullet Mugil cephalus at the southern limits of its distribution(Wiley, 2015)
;Górski, Konrad ;Gruijter, C. deTana, R.In this study, habitat use by Mugil cephalus was investigated in the waters of the west coast of the North Island of New Zealand by analysing microchemical composition of otoliths (laser-ablation inductively coupled plasma mass spectrometry) obtained from individuals from commercial fish stocks and research surveys. Results of this study show that M. cephalus at the southern limits of its distribution display highly flexible migratory behaviour with extensive use of freshwater and brackish habitats, potentially enabling them to maximize foraging opportunities. Mugil cephalus can tolerate a wide range of salinities and can therefore utilize higher productivity areas, such as estuaries and eutrophic riverine lakes. Finally, M. cephalus populations across a range of climates and latitudes appear to differ in the extent to which they utilize freshwater and brackish habitats, possibly with increasing penetration of fresh waters with increasing latitude. - PublicationIncorporating weights into real-time heuristic search(Elsevier, 2015)
;Rivera, Nicolás ;Baier, Jorge A.Hernández, CarlosMultiplying the heuristic function by a weight greater than one is a well-known technique in heuristic search. When this technique is applied to A* with an admissible heuristic it yields substantial runtime savings, at the expense of sacrificing solution optimality. Its applicability to real-time heuristic search, a search approach that builds upon heuristic search, however, has only been explored by a few studies. In this article we present two new approaches to using weights in real-time heuristic search, applicable to a wide range of algorithms. The first one, weighted lookahead, is a variant of an existing approach by Shimbo and Ishida, and utilizes the weight while the algorithm performs lookahead search. The second one, weighted update, incorporates the weight to the edges of the search graph during the learning phase. We implemented both techniques within LSS-LRTA* and evaluated them in path-planning benchmarks. We show that weighted lookahead outperforms an existing approach by Shimbo and Ishida but that it does not improve over existing approaches that do not use weights. Weighted update, on the other hand, yields performance improvements of up to one order of magnitude both in solution cost and total search time. To illustrate further the generality of weighted update, we incorporate the technique in two other well-known real-time heuristic search algorithms: LRTA*-LS and daLSS-LRTA*, and we empirically show significant improvements for LRTA*-LS and modest but still important improvements for daLSS-LRTA*. We analyze the properties of weighted update in depth, showing, among other things, that it guarantees termination. Convergence behavior of LSS-LRTA*, modified to use weighted update, is also analyzed. In such a setting, we prove solutions are w-optimal, and provide additional bounds on solution quality that in practice are tighter than w-optimality. - PublicationVirtual integration of financial markets: A dynamic correlation analysis of the creation of the Latin American integrated marketThis paper investigates the role of virtual integration of financial markets on stock market return co-movements. In May of 2011 the Chilean, Colombian, and Peruvian stock markets virtually integrated their stock exchanges and central securities depositories to form the Latin American Integrated Market (MILA). We utilize the dynamic conditional correlation model propose by Engle (2002) to identify a statistically significant positive correlation between these markets. Moreover, we find strong evidence that the creation of the MILA increased the levels of dynamic correlation between stock returns. A higher correlation was also found during the dot-com bubble and the 2007 financial crises. Our results imply a decline in gains from international diversification by holding portfolios consisting of diverse stocks of these countries.
- PublicationEquidad de acceso a la Educación Superior: El “Puntaje Ranking de Notas” como mecanismo de inclusión en el Sistema de Admisión de Chile(Universidad de San Andrés y Arizona State University, 2015)Casanova Cruz, DanielEn Chile, a partir del año 2013 se introdujo en el sistema chileno de admisión universitaria un nuevo factor de selección denominado “Puntaje Ranking de Notas”, con el objetivo de mejorar la equidad en el acceso a la educación superior. La medida ha motivado diversas objeciones y las evaluaciones realizadas han demostrado efectos modestos en alterar la inequidad de acceso a nivel general. Sin embargo, atendida la diversidad de la educación superior universitaria chilena, es en el sector más selectivo de carreras -aquel que tiene un alumnado más elitizado socialmente-, donde se esperarían efectos de alguna significación. Este documento analiza los resultados del mecanismo “Puntaje Ranking de Notas” en relación a sus objetivos declarados, en el conjunto de carreras de mayor selectividad. Usando el registro de postulantes de los años 2012 a 2014 se construyó un indicador de clasificación socioeconómica de cada sujeto, a fin de seguir los cambios en la composición social de los seleccionados de las carreras selectivas, antes y después de la incorporación del “Puntaje Ranking de Notas”. Se concluye que no existen modificaciones en la dimensión socioeconómica, a partir de la incorporación de dicho factor en el proceso de admisión. A la vez, se propone un debate más amplio sobre la relación entre políticas de inclusión y metodologías de selección para la educación superior.
- PublicationIntercultural Talent Management Model: Virtual communities to promote collaborative learning in indigenous contexts. Teachers’ and students’ perceptionsThe strong connection between technologies and globalization has made the phenomenon of interculturality increase at a global level. The aim was to determine the perception of teachers and students in the use of a Model of Talent Management for interculturality. A virtual learning environment (VLE) was used to link teachers and students of 5 schools in disadvantaged context of Chile through collaborative learning. The research is interpretive and positivist based on qualitative method approach, with quantitative contributions. Results show that talents of the students contribute to the formation of cultural identity that gives uniqueness to the human group to which they belong and the perception of teachers is that the phenomena of acculturation, enculturation and transculturation processes occur in learning linked to the management of the talents of students in intercultural contexts. With respect to the proposed model, trends indicate that it is possible to diagnose and promote talent through collaborative learning and intercultural dialogue. As for technology, it could be argued that it has reshaped relations between different cultures.
- PublicationSpecies separation within the Lessonia nigrescens complex (Phaeophyceae, Laminariales) is mirrored by ecophysiological traits(BEDIM- Biology, Ecology & Diversity of Invertebrates from Marine Environment, 2015)
;Koch, Kristina ;Thiel, Martin; ;Hagen, Wilhelm ;Graeve, Martin ;Tala, Fadia ;Laeseke, PhilippBischof, KaiLessonia nigrescens used to be an abundant kelp species along the Chilean coast, but recent molecular studies revealed the existence of a L. nigrescens species complex, which includes the two cryptic species Lessonia berteroana and Lessonia spicata. Since these species have different distributions (16°S–30°S for L. berteroana and 29°S–42°S for L. spicata), they experience differences in environmental conditions, such as solar irradiance, seawater temperature and air exposure during low tide. This study tested to what extent the genetic distinctness of each of the two species [identified by a mitochondrial marker (atp8/trnS)] is reflected by ecophysiological traits (total lipids, fatty acid composition, phlorotannins, pigments and variable chlorophyll a fluorescence of PSII) in response to the respective environmental conditions, prevailing along the latitudinal gradient. We studied algal individuals from eight populations (27°S–32°S, including the species overlapping zone). Phlorotannins, pigments and Chl a fluorescence of PSII were most crucial for species-specific adaptations at the respective growth sites, whereas changes in total lipids and fatty acid compositions were negligible. Hence, species differentiation within the L. nigrescens complex is also manifested at the ecophysiological level. These findings may help to predict kelp responses towards future environmental changes. - Publication“¡Quién fuera cronista!”, de Daniel Riquelme: Introducción a un texto recobradoEl texto que presentamos a continuación, “¡Quién fuera cronista!”, del escritor y periodista chileno Daniel Riquelme, alias Inocencio Conchalí, fue publicado el lunes 2 de enero de 1888 en la portada del diario santiaguino La Libertad Electoral, de propiedad de los hermanos Matte y uno de los principales órganos de oposición política al gobierno del presidente José Manuel Balmaceda. El texto marca el inicio del segundo año de Riquelme como colaborador habitual en este medio, luego de abandonar, en 1886, su trabajo como redactor anónimo en el influyente periódico rival La Época, considerado en su momento “el diario literario por excelencia” (Silva Castro 298) y que contaba entre sus colaboradores frecuentes a un recién llegado Rubén Darío.
- PublicationCharacterization of the productive performance of Highlander sheep in Southern Chile. II. Male reproductive traits(Elsevier, 2015)
;Cox, José F. ;Jeria, Eduardo ;Bocic, AntonioVera, NelsonBasic information on the reproductive potential of animals is required to establish sound reproductive procedures including the application of assisted reproductive technology. The study aimed to characterize the reproductive performance of rams of the Highlander breed during the breeding season. With this purpose 53 rams were allocated to two experiments: in the first one, 8 Highlander rams were compared against 8 Suffolk rams used as reference in terms of scrotal circumference, ejaculate traits and service capacity test; and in the second experiment, 37 rams and 506 ewes in a male to female ratio ranging between 1:8–24, were used to assess male fertility in terms of conception and prolificacy rates of ewes exposed. Compared to Suffolk rams, results showed that Highlander rams exhibited larger scrotal circumference (P = 0.003), tended to have both larger sperm concentration (P = 0.08) and lower volume (P = 0.098), and have similar sperm normal morphology (P = 0.63) in their ejaculates; their spermatozoa moved at lower speed (VCL, P < 0.001; VAP, P = 0.02) but more linearly (LIN, P = 0.006; ALH, P < 0.001), and rams displayed less sexual activity (effective mounts, P = 0.028; false mounts, P < 0.001). When rams were exposed for natural breeding, their average reproductive performance was consistent with the conventional targets demanded for high productivity. Although significant differences in performances were found between rams, no correlation was found between conception rate neither with male to female ratio (P = 0.82) nor with prolificacy (P = 0.95) or between male to female ratio and prolificacy (P = 0.58). Cumulative results suggest that Highlander rams exhibit an adequate potential for reproduction. However, for meeting high standards of productivity, Highlander rams need to be selected by potential fertility of their ejaculates and service capacity in addition to the conventional breeding soundness evaluation. - PublicationA contract for coordinating capacity decisions in a business-to-business (B2B) supply chain(Elsevier, 2015)
;Araneda Fuentes, Cristina ;Junqueira Lustosa, LeonardoMinner, StefanWe address the problem of coordinating the capacity decisions of two autonomous manufacturers engaged in a buyer–supplier relationship. We propose and analyze a supply contract designed to coordinate the companies׳ single period capacities so that both parties end up better off than they would by trading solely through the market. The setting is frequently found in supply chains, as the contract does not forbid the parties to also trade in the market. Under the proposed contract, each party decides on his own medium term capacity when demands are still only probabilistically known. When the demand is realized, the supplier must sell to the buyer at a discount contract price up to a contract reservation quantity, and the buyer will pay a contract penalty for each unit he reserved but did not order. The supplier can sell any leftover capacity on the market and if the buyer needs more than the reserved quantity, he must purchase from the supplier at market price or from the market if the supplier׳s capacity does not suffice. The main achievements gained through this research are (i) conditions for the companies׳ capacity decisions to obtain coordination under the contract, (ii) conditions for the contract to coordinate the parties׳ decisions and leave both better off, (iii) characterization of contract instances in which the profit can be arbitrarily distributed between the parties, and (iv) identification of two distinct kinds of gain produced by the contract. Finally, we illustrate the main properties of the contract with numerical examples. - PublicationAssessment of social perception on the contribution of hard-infrastructure for tsunami mitigation to coastal community resilience after the 2010 tsunami: Greater Concepcion area, Chile(International journal of disaster risk reduction, 2015)
; ;Yu Ting, Joanne ;Pawel-Jarzebski, Marcin ;Dyah, Fatma ;San Carlos, Ricardo ;Jianping, Gu ;Esteban, MiguelTomohiro, AkiyamaA GIS analysis on the urbanization spread (1725 to present) in the Greater Concepcion Region demonstrates that increasing the tsunami disaster resilience of coastal communities is a pressing issue in Chile, due to the continuous presence of human settlements in tsunami-prone areas. This research assesses the contribution of “hard-infrastructure” for increasing disaster resilience within five coastal towns (Dichato, Coliumo, Tumbes, Penco and Talcahuano). Structures were considered beneficial to resilience-building if they had multi-functional properties which aided in the social and/or economic recovery of the affected community. The assessment was carried out through in-depth interviews with local inhabitants until the point of data-saturation. Results reveal that all surveyed coastal towns had hard-infrastructure that was built after 2010, in the form of promenades and elevated housing. The former structures contributed positively to building economic resilience in Dichato, Talchuano and Penco, through the promotion of tourism and small-scale fishing activities. However, the physical design of the elevated houses was found to only facilitate recovery of community economic functions in Tumbes, while causing strain on the social fabric and possibly hindering tsunami evacuation in all other study sites. The mixed contribution of hard-infrastructure to coastal resilience highlights the need for the de-centralization of planning and reconstruction processes for a successful contextualization of the issue. - PublicationCaracterización del profesor evangelizador católicoEl fin último de un Proyecto Educativo en nuestro contexto de colegios católicos es el desarrollo integral y armónico de toda la persona, preocupándose de la formación total de cada estudiante, como un ser amado personalmente por Dios. Por ello, su objetivo central consiste en ayudar al desarrollo más completo posible de todas las capacidades o talentos dados por Dios a cada persona. Este desafío pastoral de la Iglesia requiere de un tipo de profesor que sea el mediador de la formación de estos valores e ideales cristianos, buscando promoverlos entre cada uno de sus profesionales, particularmente con los docentes que laboran en el centro educativo. El propósito de esta investigación es llegar a la caracterización del profesor evangelizador católico para las Fundaciones Educacional Cristo Rey y la Asunción y otros establecimientos católicos. Los datos fueron levantados a través de diversas metodologías de investigación cualitativa, como entrevistas, focus group y análisis documental, los que permitieron identificar las principales características que deben tener los profesores y directivos de los colegios católicos para poner en práctica el Proyecto Educativo según ha sido definido en los documentos magisteriales de la Iglesia Católica.
- PublicationNew fully-mixed finite element methods for the Stokes-Darcy coupling(Elsevier, 2015)
;Camaño Valenzuela, Jessika ;Gatica, Gabriel N. ;Oyarzúa, Ricardo ;Ruiz-Baier, RicardoVenegas–Tapia, PabloIn this paper we introduce and analyze two new fully-mixed variational formulations for the coupling of fluid flow with porous media flow. Flows are governed by the Stokes and Darcy equations, respectively, and the corresponding transmission conditions are given by mass conservation, balance of normal forces, and the Beavers–Joseph–Saffman law. We first extend recent related results involving a pseudostress/velocity-based formulation in the fluid, and consider a fully-mixed formulation in which the main unknowns are given now by the stress, the vorticity, and the velocity, all them in the fluid, together with the velocity and the pressure in the porous medium. The aforementioned formulation is then partially augmented by introducing Galerkin least-squares type terms arising from the constitutive and equilibrium equations of the Stokes equation, and from the relation defining the vorticity in terms of the free fluid velocity. These three terms are multiplied by stabilization parameters that are chosen in such a way that the resulting continuous formulation becomes well-posed. The classical Babuška–Brezzi theory is applied to provide sufficient conditions for the well-posedness of the continuous and discrete formulations of both approaches. Next, we derive a reliable and efficient residual-based a posteriori error estimator for the augmented mixed finite element scheme. The proof of reliability makes use of the global inf–sup condition, Helmholtz decomposition, and local approximation properties of the Clément interpolant and Raviart–Thomas operator. In turn, inverse inequalities, the localization technique based on element-bubble and edge-bubble functions, and known results from previous works, are the main tools to prove the efficiency of the estimator. Finally, several numerical results illustrating the good performance of both methods, confirming the aforementioned properties of the estimator, and showing the behavior of the associated adaptive algorithm, are provided. - PublicationEl cuestionamiento del poder como dominio: Repensar los análisis de poder en la acción socialUna revisión de nuestras bases teóricas puede ayudar a desmarcarnos de los límites conceptuales que terminan por condicionar y reproducir representaciones ideológicas hegemónicas sobre el poder. La pretensión de este artículo es cuestionar los términos que configuran el concepto de poder y los sustentos imaginarios tradicionalmente usados en su análisis; acercarnos a propuestas que ofrezcan alternativas para la construcción de nuevos idearios sobre los que abrir campos de reflexión y análisis de las formulaciones e intervenciones en el campo de la acción social y que permitan visibilizar opacadas formas de distribución de la autoridad presentes en la diversidad sociocultural latinoamericana.
- Publication¿Influyen las emociones en la intención de asistir a un evento deportivo? Diferencias de género(Journal of Sports Economics & Management, 2015)
;Alonso Dos Santos, ManuelPérez-Campos, CarlosLa calidad y la satisfacción son importantes predictores de la intención de asistencia a los eventos deportivos. Su influencia ha sido verificada en la literatura académica. Sin embargo, y a pesar de la relevancia de las emociones en la predicción del comportamiento, aun son pocos los estudios al respecto. Esta investigación aporta un nuevo punto de vista al estudiar la influencia de las emociones sobre la satisfacción, incluyendo el efecto moderador del género. Se entrevistó a 637 individuos en un evento internacional de atletismo. Hemos empleado mínimos cuadrados parciales consistentes con el objetivo de validar las escalas y posteriormente testar las hipótesis. Todas son soportadas. Las emociones y la calidad son predictores de la satisfacción, y ésta de la intención de asistencia. Respecto al género, se encontraron diferencias en la relación activación – satisfacción, no siendo soportada en el segmento de las mujeres. Son recomendadas estrategias de comunicación segmentadas en el apartado de conclusiones. - PublicationCapital budgeting practices in SpainThis paper seeks to shed further light on the capital budgeting techniques used by Spanish companies. Our paper posits that the gap between theory and practice might be related to the nature of sources of value and to the efficiency of mechanisms aligning managerial and shareholder incentives, rather than to resource restrictions or model misinterpretation. We analyze data from a survey conducted in 2011, the final sample comprising 140 non-financial Spanish firms. Our findings show a behaviour pattern similar to that reported in prior research for firms in other countries. Particularly noteworthy is that payback appears to be the most widely used tool, while real options are used relatively little. Our results confirm that size and industry are related to the frequency of use of certain capital budgeting techniques. Further, we find that the relevance of growth opportunities and flexibility is an important factor explaining the use of real options.
- PublicationUna relectura leibniziana al mecanicismo(Universidad del Norte, 2015)Kasahara, JavierEl propósito de este artículo es desarrollar una relectura al mecanicismo moderno. Esto implica que una adecuada comprensión de este consiste, ante todo, en considerarlo como un proyecto antes que un sistema doctrinal consolidado. Para ello se toma como eje la filosofía de Leibniz, la cual, a diferencia del cartesianismo, identifica las inconsistencias que implica concebir el mecanicismo como un sistema filosófico completo, principalmente al pretender justificar mecánicamente el mundo natural, esto es, a partir de la figura, el tamaño y el movimiento. Todo lo anterior no implica un rechazo completo del mecanicismo por parte de Leibniz, sino que permite concebirlo como un medio para desarrollar su filosofía, proponiendo una complementariedad entre la causa final y la causa eficiente. de este modo, el mecanicismo es reubicado como un problema metodológico para la ciencia natural antes que como un problema metafísico.
- PublicationCharacterization of Baker Fjord region through its heavy metal content on sediments (Central Chilean Patagonia)(Pontificia Universidad Católica de Valparaíso, 2015)
;Ahumada, Ramón; ; Silva, NelsonThe spatial distribution of heavy metals content (Ba, Cd, Cu, Pb, Sr and Zn) in sediments of the Baker Fjord and surrounding channels in the central region of the Chilean fjords (47°45'S, 48°15'S) is analyzed. The aim of the study was characterized the patterns of abundance and distribution of these metals in surface sediments. The area corresponds to a poorly studied zone with low human activity. Distribution patterns would be influenced by rainfall conditions (local erosion), fluvial (continental sediments carried by rivers), glacier (glacier flour) and estuarine circulation. Cluster analysis allows differentiation among the sampled sites and group with similar characteristics. Finally, the concentrations found were contrasted with average values of metamorphic rocks and show with some certainty that the values found for calendar for this area and the greatest concentrations are the result of natural enrichment. - PublicationAprendizaje y rendimiento académico en educación superior: Un estudio comparado(Actualidades Investigativas en Educación, 2015)
;García-Gajardo, Fernando ;Fonseca-Grandón, GonzaloConcha-Gfell, LisbethEl presente artículo expone el resultado de dos investigaciones desarrolladas con el propósito de determinar el repertorio de estrategias de aprendizaje (EA) y su relación con el avance curricular y el rendimiento académico de la población estudiantil de dos instituciones de Educación Superior Chilenas, ubicadas en la V y VIII región del país. En ambos casos se aplicó el test de Adquisición, Codificación, Recuperación y Apoyo al Procesamiento de la Información (ACRA). El primer caso corresponde a jóvenes de una carrera de formación de docentes en Educación Primaria y el segundo, a estudiantes pertenecientes a una carrera de nivel técnico, de una institución de las Fuerzas Armadas chilenas. La muestra fue de 342 estudiantes, a quienes se les administró el test entre los años 2010 y 2014. Los hallazgos del estudio develaron que, en general, ambos grupos al ser medidos, contaban con un repertorio de EA escasas. Por otra parte, en el supuesto de que las EA aumentaban mientras se avanzaba en la formación curricular (en este caso de profesores de Primaria), las evidencias arrojaron que ello no ocurre y que estas, se mantienen estables a lo largo de dicho proceso. Finalmente, se corroboró lo que también, en otros trabajos de investigación se ha descubierto, en cuanto a que los estudiantes que tienen un buen rendimiento poseen un repertorio mayor de EA que los que logran un menor rendimiento. - PublicationA RTk - P-k approximation for linear elasticity yielding a broken H(div) convergent postprocessed stress(Applied Mathematics Letters, 2015)
; ;Gatica, GabrielSequeira, FilánderWe present a non-standard mixed finite element method for the linear elasticity problem in Rn with non-homogeneous Dirichlet boundary conditions. More precisely, our approach his based on a simplified interpretation of the pseudo stress–displacement formulation originally proposed in Arnold and Falk (1988), which does not require symmetric tensor spaces in the finite element discretization. We apply the classical Babuˇ ska–Brezzi theory to prove that the corresponding continuous and discrete schemes are well-posed. In particular, Raviart–Thomas spaces of orderk≥0 for the pseudo stress and piece wise polynomials of degree ≤k for the displacement can be utilized. In addition, complementing the results in the afore mentioned reference, we introduceanewpostprocessingformulaforthestressrecoveringtheoptimally convergent approximation of the broken H(div)-norm. Numerical results confirm our theoretical findings.