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Item Seaweed restocking along the Chilean coast: History, present, and inspiring recommendations for sustainability(2023-01-09) Oyarzo-Miranda, Carolina; Otaíza, Ricardo; Bellorín, Alexis; Alonso Vega, J.M.; Tala, Fadia; Lagos, Nelson A.; Oyarzún, Fernanda X.; Estévez, Rodrigo A.; Latorre-Padilla, Nicolás; Mora Tapia, Ana María; Figueroa-Fábrega, Luis; Jara-Yáñez, Roddy; Bulboa, Cristian; Contreras-Porcia, LorettoSeveral seaweed species are commercialized worldwide both due to high demand for food and feed and as a raw material for the extraction of phycocolloids such as agar, carrageenan, and alginates that are used broadly in the food, cosmetic, and pharmaceutical industries. Chile is the world’s leading marine seaweed biomass producer when it comes to the exploitation of natural kelp beds. This extraction pressure has persisted for decades and has resulted in a reduction in natural stocks along the benthic ecosystems of the Chilean coast. Over the last three decades, several strategies aimed at restoring seaweed stocks have been implemented (i.e., sexual and asexual reproduction, the use of spore-type propagules or fragments of thalli, and entire thallus transplants). Success rates have varied, but the biological feasibility of such strategies has been demonstrated for several species. However, technological improvements must be achieved to move from small-scale, pilot experiments to cost-effective restocking strategies that are easy to transfer to fisher communities and another end-user, scalable to marine field conditions, and socio-ecologically sustainable. Researchers in other geographic areas have explored similar pathways for developing kelp restocking strategies and have tackled the research gaps regarding its massification. This work summarizes the research activities carried out in recent decades in the search for sustainable strategies to restore algal stocks in Chile.Item Hydrolyzed protein from Lupinus albus (INIA-Boroa variety) for the functional food industry: An example of partnership between farmers and academia(2023-01-04) Oliveira, Patricia E.; Benavides, Sergio F.; Huenufil, Daniel; Zarate, Pablina; Petit-Breuilh, XimenaThis work presents investigations carried out to obtain by-products of bitter lupine (Lupinus albus), using a variety created specially in the Chilean Agricultural Research Institute (INIA). We present new information on obtaining protein isolates and hydrolysates as a way of adding value to bitter lupine, which promises to help return this crop to profitability in Chile. Lupine in this country is produced almost exclusively in the Araucanía Region, for the most part by small-scale farmers of the Mapuche ethnic group. An experimental design was drawn up based on one-factor experiments, for obtaining both protein isolate and protein hydrolysate. The best process conditions were achieved with stirring times of between 60 and 90 min; the concentrations (consistency of the mixture) were between 5 and 10%, with pH of the solution 12. The maximum yield achieved was 33% pure protein isolate (dry weight). After the protein isolates had been formulated, they were characterised by their functional properties: solubility, water retention capacity, lipid adsorption index, swelling capacity and foam stability. These properties are important for determining the quality of the protein hydrolysate, as they will affect its digestibility and thus its bioavailability in the organism. The protein hydrolysate was characterised by its complete proximal parameter, vitamins, total sugars, and amino acids. These results show that Lupinus albus (var. INIA-Boroa) is an excellent raw material for the existing functional foods industry.Item Conocimiento, prevalencia y valoración de prácticas deshonestas en estudiantes universitarios de Artes y Humanidades y de Ciencias de la Salud(2022-10) Vásquez-Rocca, Liliana; Cuba Raime, Claret; Vásquez Velasco, CarolinaEl avance tecnológico trajo consigo ventajas y desventajas en el ámbito académico, dando la posibilidad a las y los estudiantes y profesoras y profesores de acceder a una amplia información especializada. Entre las desventajas, se ubica el plagio, la copia y otras acciones similares. De hecho, la práctica deshonesta más frecuente entre las y los estudiantes del mundo es el plagio académico. Al respecto, las indagaciones en esta área son múltiples y desde diferentes aproximaciones teóricas. A nivel iberoamericano, Sureda, Comas y Urbina, (2005) y Comas-Forgas y Sureda-Negre (2010) realizaron estudios pioneros en el campo. En este marco, esta investigación tiene como objetivo comparar el conocimiento, prevalencia y valoración de prácticas deshonestas por parte de las y los estudiantes ingresantes a la universidad de las disciplinas de Artes y Humanidades (Perú) y de las Ciencias de la Salud (Chile). El método utilizado es el cuantitativo descriptivo con un diseño no experimental y transversal, la muestra consideró 217 participantes a los cuales se les aplicó un cuestionario validado previamente. Tras el análisis, los resultados muestran que el conocimiento del plagio y de las referencias no difiere entre ambos campos del saber. En cuanto a la prevalencia y valoración, en su mayoría presentan datos similares, salvo acciones y prácticas específicas que su sanción podría estar más normada por cuerpos legales.Item Scratch and Arduino for Effectively Developing Programming and Computing-Electronic Competences in Primary School Children(2019-11) Vidal-Silva, Cristian; Serrano-Malebran, Jorge; Pereira, FelipeProgramming and designing computing-electronic solutions imply complex competences, which usually demand to restructure previous thinking and problem-solving knowledge. Both programming and computing-electronic design solutions ask for step-by-step thinking, and also being cautious regarding involved hardware items for the second one. Designing computing-electronic solutions is a non-trivial task since it unifies both worlds, even though platforms such as Arduino notably simplify that development. This article describes experiences of programming and computing-electronic teaching to a group of primary school children in Valparaiso-Chile by the use of Scratch and Tinkercad for the goal of developing programming and Arduino-based computing-electronic competences in school children. The obtained results demonstrate that children can effectively develop programming and computing-electronic theoretical and practical skills. These results also show that students can get abilities and enthusiasm to know more advanced skills and applications concerning sensing systems. Thus, programming and electronics can motivate the learning process in children.Item Cambios en la densidad y distribución espacial de las poblaciones del género Fissurella Spp. (Fissurellidae) y de Concholepas Concholepas (Muricidae), en áreas de manejo y explotación de recursos bentónicos con extracción de Lessonia Trabeculata (Phaeophyceae) de las regiones de Atacama y Coquimbo.(2020-08) Morales Gallardo, Vanessa; Padilla Zambrano, Tiare; Figueroa-Fábrega, Luis; Ariz, LuisLessonia trabeculata es conocida por su rol como estructurador del ecosistema marino. Sin embargo, en la actualidad, las densidades naturales del alga han disminuido considerablemente, debido a la intensa actividad extractiva. Concholepas concholepas, Fissurella latimarginata y Fussurella cumingi son especies que cohabitan con huiro palo, por ende, dependen en gran medida unas de otras. Por este motivo el objetivo de este estudio es determinar si la extracción del recurso L. trabeculata genera cambios en la dinámica de las poblaciones submareales de C. concholepas, F. latimarginata y F. cumingi. Para ello se analizaron las densidades históricas registradas en AMERBs representativas de las Regiones de Atacama y Coquimbo. Los resultados muestran que tanto en las áreas de manejo de Atacama como en las de Coquimbo existen cuatro tendencias marcadas en la relación entre las densidades de L. trabeculata y C. concholepas, F. latimarginata y F. cumingi, observándose que áreas donde la densidad del huiro palo es alta, existen dos posibles situaciones; la primera en donde también lo es para los otros recursos asociados o que no lo sea. Y la segunda, en donde la baja densidad de huiro palo, genera mayor o menor densidad en el resto de los recursos.Item Utilización de los Índices de Hábitat Fluvial, Bosque de Ribera y Macrófitas para la Determinación de Calidad del Recurso Hídrico del Estero Catapilco, Región de Valparaíso(2015-03-02) Silva Haun, Rodrigo; Arancibia Fortes, JavierEl Estero Catapilco está ubicado en Chile central. Su alimentación corresponde a un régimen 100% pluvial, desarrollándose flora mediterránea en su cauce (bosque esclerófilo e hidrófilo). La intervención antrópica ha modificado la vegetación ribereña, el caudal disponible y la calidad del agua. Para caracterizar la calidad del recurso hídrico se estableció seis (6) estaciones a lo largo de la cuenca, aplicando en cada una de ellas el Índice de Hábitat Fluvial, Índice de Calidad Bosque de Ribera y el Índice de Macrófitas. Dichos resultados fueron correlacionados utilizando la metodología de Spearman (1904) con los análisis físicos y químicos realizados al agua. El análisis de la calidad del agua del Estero Catapilco mostró que estas no se encontraban en la mejor condición. La correlación con muestreos físicos y químicos de las aguas, mostró marcadas diferencias entre ambas metodologías. Estas situación puede deberse a la baja diversidad de especies nativas y un número importante de especies introducidas, lo que incide directamente con los valores entregados por los índices. Asimismo se observó que los cambios en el uso de suelo, aumento de plantaciones forestarles, está influyendo en la cantidad del recurso hídrico disponible en la cuenca.Item Developing Computing Competencies Without Restrictions(2022-10-04) Vidal-Silva, Cristian; Barriga, Nicolás A.; Ortega-Cordero, Franco; González-López, Javiera; Jiménez-Quintana, Claudia; Pezoa-Fuentes, Claudia; Veas-González, IvánThe information society represents a great revolution. Computing programming is a relevant competence nowadays for everybody, regardless of educational background. However, traditional programming languages consider syntax barriers that complicate their adoption and usefulness for beginners. Python is an exception for its open-source, cross-platform nature and syntax simplicity, which facilitate the development of algorithmic thinking and dissemination of programming solutions. Several Python extensions support modern functionalities such as web development, videogame, and machine learning, making it one of the most used programming languages. Google Colab or Colaboratory facilitates the online learning and development of Python solutions. This article presents positive academic experiences of Chilean students of majors from two Chilean universities, a traditional university in the north and a private university in the middle of Chile, using Google Colab to develop programming competencies remotely for the Covid pandemic. We highlight the promising results obtained for basic programming and operating system programming subjects, which motivate us to use Python and Google Colab widely, not only in university contexts. We expect to continue developing programming competencies using Google Colab and Python. The main limitation encountered in this experience is the internet connection requirements for online education. However, it does not represent an issue for education in developing and developed countries. Google Colab permits the development of highly demanded competencies worldwide at home, only with internet access and a web browse, an excellent motivation for learning for all students regardless of age and academic level.Item Gravitational Decoupling algorithm modifies the value of the conserved charges and thermodynamics properties in Lovelock Unique Vacuum theory(2022-02-04) Estrada, MilkoWe provide an extension of the Gravitational Decoupling (algorithm) for the Lovelock theory with Unique Vacuum (LUV), which represents a simple way to solve the equations of motion. Due to the application of this algorithm, the energy of the system splits in the energy of the seed solution and the energy of each quasi-LUV sector. Under certain assumptions imposed, the total energy varies due to the contribution of energy of each quasi-LUV sector. It is provided a new solution, whose energy differs from the energy of the seed solution in a quantity that depends on the number of extra sources. The new solution has two inner horizons, which is a proper characteristic of itself. Furthermore, its thermodynamics differs from the seed solution, since our solution is always stable and does not have phase transitions. Since the first law of thermodynamics is modified by the presence of the matter fields, we provide a new version of the first law for LUV, where a local definition of the variation of energy is defined, and, where the entropy and temperature are consistent for LUV theory.Item Metodologías activas para la enseñanza de programación a estudiantes de ingeniería civil informática(2022-06) Jones, Eduardo A.; Jimenez, Claudia A.; Ormeño, Pablo I.; Poblete, Natalia A.El objetivo de este estudio es monitorear el impacto de la aplicación de metodologías activas de enseñanza para programación en la carrera de Ingeniería Civil Informática de la Universidad Viña del Mar (Chile). Los cursos de programación se encuentran actualmente en casi todos los primeros niveles de las carreras de ingeniería, especialmente los relacionados con informática. Se aplica un cuestionario para diagnosticar la relación de los estudiantes con los contenidos, al inicio y al término del semestre, realizando preguntas relacionadas con los primeros niveles de la taxonomía de Bloom. Los resultados muestran que la aplicación de metodologías activas mejora la tasa de aprobación de la asignatura y mejora las habilidades de recordar y comprender de los estudiantes. Sin embargo, no hay evidencia que demuestre si en la habilidad de aplicación hay algún impacto. Se concluye que las metodologías activas funcionan cuando son aplicadas en cursos de programación de computadoras.Item Spatial Pattern of Genetic Diversity in the Blood Fluke Aporocotyle argentinensis (Digenea, Aporocotylidae) from South American Hakes (Pisces: Merluccidae)(2022-09-19) Oliva, Marcelo E.; Cárdenas, Leyla; Valdivia, Isabel M.; Bruning, Paulina; Figueroa-Fabrega, Luis; Escribano, RubénDistribution of blood fluke Aporocotyle spp. parasitizing Merluccius species from the coasts of South America (Peru, Chile and Argentina) constitutes an excellent opportunity to evaluate the geographical amplitude in which a parasite can exploit the same host species. Phylogenetic analyses (partial sequences of SSU rDNA, LSU rDNa, and cox1 gene) were performed to characterize the genetic lineage of Aporocotyle species described from South American Hake: Merluccius australis, M. gayi, and M. hubbsi. The Phylogenetic analyses (SSUrDNA and LSUrDNA) revealed an absence of genetic variability in Aporocotyle obtained over a gradient of 6800 km, covering two oceans and three closely related hosts. Consequently, the species infecting Merluccius spp. in South America is Aporocotyle argentinensis Smith 1969, by priority law. Phylogeographic analysis suggests a pattern of spatial differentiation and genetic population structure associated with the geographical distribution of the host’s species. A specimen with a haplotype found in M. gayi was collected from M. australis from Puerto Montt, and three worms (from Coquimbo, Constitución and Talcahuano, host M. gayi) harbored a haplotype found in M. australis + M. hubbsi, suggesting that the gene flow between different hosts and geographical distributions occurs when the distribution of adequate hosts overlaps, avoiding speciation in blood flukes from South American hakes.Item Manufacture of a bio-tissue based on nanocrystalline cellulose from chilean bamboo Chusquea quila and a polymer matrix using electrospinning(Nano-Structures & Nano-Objects, 2020) Petit-Breuilh, Ximena; E.Díaz, Paola; Gacitúa, William; E.Oliveiraa, Patricia; E.Oliveira, PatriciaPolymers of renewable origin have aroused great interest among researchers due to their sustainable, environmentally friendly nature. This work presents a biopolymer called bio-tissue, as it is created by electrospinning. This bio-tissue was formed with a polymer matrix of cellulose acetate (CA) reinforced with crystalline cellulose (NCC) derived from an autochthonous Chilean bamboo species of no commercial value which is considered a pest, Chusquea quila or quila. Bio-tissues were produced with three concentrations of NCC (1, 5 and 10% as a dry weight proportion of cellulose acetate) and their technological potential as an interior coating in small constructions was assessed. The morphology of the bio-tissues showed that the CA nanofibers containing NCC were of better quality and more uniform diameter than pure CA. The thermal profile showed that the highest concentration of NCC (10% as a dry weight proportion of cellulose acetate) induced earlier degradation; it was less thermally stable and decomposed at lower temperatures. The bio-tissue with 5% as a dry weight proportion of cellulose acetate showed the greatest resistance to traction with a break-point of 30 MPa and an elasticity module of 1.597 MPa. Finally, it was shown that the permeability to water vapour, oxygen and carbon dioxide was low, allowing regulated passage of these molecules. These results show the feasibility of using cellulose nanofibers as a reinforcement in polymer matrices; this could have various applications in fields ranging from the construction industry to food packaging.Item Effect of a thermal pretreatment on dissolution kinetics of a limonitic lateriteore in chloride media(Hydrometallurgy, 2020) Garces-Grandaa, A.; Lapidusb, G.T.; Restrepo-Baena, O.J.The effect of a thermal pretreatment on the kinetic parameters and rate-controlling step for nickel leachingdissolution in hydrochloric acid‑sodium chloride solutions from a low–grade Colombian nickel laterite (1.15%Ni, 0.12% Co and 41.1% Fe), was evaluated. The mineralogical analysis showed that nickel is associated withiron in the form of hematite (Fe2O3) and goethite (FeOOH) within the calcined and uncalcined ore, respectively.The hydrochloric acid and total chloride ions concentrations, as well as the leaching temperature, were shown tohave a direct effect on nickel extraction. The experiments showed that ~92% of nickel can be dissolved afteronly 25 min in a 3 M HCl and 2 M NaCl solution when the leaching temperature was increased to 60 °C, after thesample had been previously calcined at 430 °C for 1 h. Nickel dissolution can be described by the chemicalreaction-controlled shrinking particle model for both the calcined and uncalcined sample with apparent acti-vation energies of 98 kJ/mol and 103 kJ/mol, respectively. This result suggests that a thermal pretreatmentstage does not affect the nickel reaction mechanism, although it may liberate the nickel within the lateritestructure.Item Marine stocking in Chile: a review of past progress and future opportunities for enhancing marine artisanal fisheries(2021-08-24) Cárcamo, P. Francisco; Henríquez-Antipa, Luis A.; Galleguillos, Francisco; Figueroa-Fábrega, Luis; Taylor, Matthew D.Chile has a long history of restocking, stock enhancement, and translocation to support artisanal or small-scale fisheries; however, these programs have been scarcely discussed in the scientific literature. Here, we present a review of previous initiatives and discuss specific areas for future progress. We identified 204 releases across 117 different areas, involving 7 taxonomic groups and 22 species (20 marine and 2 freshwater). Marine stocking mainly occurred within the context of the spatial framework through which artisanal fisheries are managed [Management and Exploitation Areas for Benthic Resources (MEABR)], and over 60% involved translocation of wild individuals rather than release of hatchery-reared seed. While “stock enhancement” was the primary intention for most releases, it is unclear whether depleted spawning biomass or other recruitment limitations were the primary motivation, and few projects reported more than one stocking event. The echinoid Loxechinus albus and the gastropod Concholepas concholepas were the main target species. Only 6% of projects examined reported positive results that could be linked to releases, and none reported the use of tagging or analysis of costs or benefits. There are several areas for targeted development that should improve the social and economic outcomes from marine stocking activities. This synthesis provides a snapshot of marine stocking in Chile to date and highlights opportunities that are relevant to both Chile and other nations with substantial small-scale fisheries.Item A new model of regular black hole in (2 + 1) dimensions(2021-06-28) Estrada, Milko; Tello Ortiz, FranciscoWe provide a new regular black hole solution in (2 + 1) dimensions with the presence of matter fields in the energy momentum tensor. The inclusion of our proposed energy density plus a negative cosmological constant allows that the solution can have both flat as de Sitter or Anti-de Sitter core. This latter is a proper characteristic of our solution, because other models of regular black holes have only a single type of core. Since the first law of thermodynamics for regular black holes is modified by the presence of the matter fields, we provide a new version of the first law, where a local definition of the variation of energy is defined, and where the entropy and temperature are consistent with the ones previously known in the literature. At the hypothetical limit when the horizon radius r+ → ∞ the usual first law dM = TdS is recovered. The effectiveness of the formalism used to compute the mass of our regular black holes in (2 + 1) dimensions suggests the potential applicability of this method to calculate the mass of other models of regular black holes in d ≥ 4 dimensions.Item The intensity of kelp harvesting shapes the population structure of the foundation species Lessonia trabeculata along the Chilean coastline(2021) Gouraguine, Adam; Moore, Pippa; Burrows, Michael T.; Velasco, Eliana; Ariz, Luis; Figueroa‑Fábrega, Luis; Muñoz‑Cordovez, Rodrigo; Fernandez‑Cisternas, Italo; Smale, Dan; Pérez‑Matus, AlejandroKelp are foundation species that support high levels of biodiversity and, either directly or indirectly provide a wide range of ecological goods and services to human society. In recent decades, due to the high demand for kelp-derived products such as alginate, commercial wild harvesting has increased, leading to declines of kelp biomass in some regions. Chile accounts for 40% of the global kelp harvest, with the subtidal kelp, Lessonia trabeculata being one of the main target species. Currently, however, there is a lack of information on how different degrees of harvesting intensity, governed by distinct management regimes and their enforcement influences L. trabeculata populations. Here we examined the effect different management regimes, characterised by distinct levels of exploitation of kelp and kelp-associated fauna, have on L. trabeculata density and morphology along ~ 1600 km of the Chilean coastline. The findings demonstrated that harvesting intensity likely influences both L. trabeculata density and morphology. Juvenile density of L. trabeculata was five times higher in the most harvesting-affected areas, while kelp morphology values, including holdfast diameter, number of stipes and total length, were always higher in the less-intensively harvested areas. Our study suggests that different degrees of protection can influence density and morphology of subtidal L. trabeculata populations, which in turn has important implications for the conservation of the kelp forest ecosystems and management of this important fishery.Item Production of cellulose nanostructures from Chilean bamboo, Chusquea quila(2020) Oliveira, P.E.; Petit-Breuilh, X.; Rojas, O.J.; Gacitúa, W.In Chile, bamboo bushes of Chusquea quila genus (or popularly known as ‘quila’) have brought economic and ecological problems for decades in the south-central part of this country. On the other hand, this plant species was studied as a raw material for the production of nanofibrillated cellulose (CNF) and nanocrystalline cellulose (CNC), presenting an opportunity for sustainable and environmentally friendly management, positioning Chile as a Latin American country at the forefront of studies with nanotechnological approaches. The methodology applied to generate these nanostructures contemplated hydrolysis with sulfuric acid and oxalic acid, in addition to an intermediate stage of microfluidization to generate nanofibrillated cellulose. The products obtained showed morphological and topographic homogeneity in the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images. The diameter values of the particles ranged from 10 to 20 nanometers for the CNCs. Through Fourier transformed spectrophotometry (FTIR) it was found that the processes of microfluidization and acid hydrolysis did not affect the molecular shape of the nanostructures and X-ray diffraction (XRD) was important to determine crystallinity index (IC), presenting values higher than 80%.Item Development Of Algorithmic And Mathematical-Logic Competences Of Children In Chile With Scratch(2020-04) Vidal-Silva, Cristian; Jiménez, Claudia; Madariaga, Erika; Tupac Yupanqui, Miguel; Sepúlveda, SussanAlgorithmic competences for the development of organized operations play an important role in the progress of education and learning of the logical and mathematical reasoning for children. In this context, the visual programming language Scratch is a viable tool for that purpose. Precisely, the main objective of this work is to present experiences and results of the use of that programming language with students of the primary school second year in various Chilean educational institutions, that is, in a public school, in a private school and in a private-subsidized school. These schools are in different geographical areas of the Maule region. Thanks to their social and cultural diversity along with their location, the obtained results are of a great relevance to demonstrate empirically that a significant gap does not exist for the development of algorithmic and logical-mathematical competences in children.Item Dinámica metapoblacional, ocupación espacial y migración en bivalvos de importancia comercial: el caso de la almeja Tawera gayi (Bivalvia: Veneridae) en el Mar Interior de Chiloé(2018) Figueroa Fábrega, Luis; Bravo Samaha, Javiera; Silva Haun, Rodrigo; Padilla, TiareTawera gayi (Hupe, 1854), es un molusco bivalvo conocido comúnmente como Juliana, cuya extracción comercial en Chile se concentra tanto en la zona norte del mar interior de Chiloé cómo en las inmediaciones de las islas Desertores. Según las estadísticas pesqueras, los desembarques han disminuido progresivamente en el último tiempo, para lo cual se han esgrimido razones relacionadas tanto con el mercado, la sobreexplotación del recurso y a la no inclusión de la conectividad espacial de los distintos bancos locales en el manejo pesquero. Por lo que el estudio de la dinámica de metapoblaciones (i.e. la variación temporal de la ocupación de los parches) puede ser una herramienta útil para comprender los patrones de abundancia de aquellas especies que presentan una alta conectividad espacial. En el presente trabajo se realizaron simulaciones para dos escenarios descritos en la zona, para dar respuesta a una serie de interrogantes relacionadas con la conectividad espacial entre bancos, los efectos de la disminución en la conectividad y el grado de incidencia de algunos de ellos. Los resultados nos indican que, al disminuir la disponibilidad de larvas por perdida de la fracción reproductiva, se reduce la probabilidad de colonización, afectando además la probabilidad de dispersión y la incidencia entre bancos cambiando la dinámica de la metapoblación. En una perspectiva temporal, se constato que la población de Juliana paso de tener una alta conectividad entre los bancos a una condición de auto reclutamiento de algunos bancos particulares de mayor tamaño, tal como se ha visto en otras almejas de importancia comercial. Por consiguiente, es fundamental considerar la conectividad espacial en el manejo pesquero, considerando además los efectos sinérgicos que la extracción de especies de interés comercial pueda generar en los ecosistemas marinos del mar interior de Chiloé.Item Propuesta de Modelo de Características con Interfaz de Punto de Unión para el Modelamiento de Líneas de Productos de Software(2018) Vidal-Silva, Cristian; Bustamante, Miguel A.; Rubio, José Miguel; Carter, LuisEn búsqueda de una nueva metodología de desarrollo de software modular, este trabajo propone MC JPI, esto es, Modelos de Características (MC) con Interfaz de Punto de Unión (JPI del inglés Join Point Interface) de Programación Orientada a Aspectos (POA) como base de la metodología Programación Orientada a la Característica (FOP) + JPI. Así, este trabajo describe ventajas y detalles de FOP y POA JPI como paradigmas individuales y de su simbiosis para la producción de software modular. Como aplicación ejemplo, se utiliza MC JPI sobre un ejemplo clásico de FOP para visualizar componentes propios de MC tradicionales, y asociaciones o restricciones cruzadas especiales entre características. Adicionalmente, este trabajo describe las ventajas de MC JPI y las diferencias respecto a algunos trabajos de investigación anteriores para apoyar principios de modelado orientados a aspectos propios de JPI. Se concluye que JPI permite una modularización sobre modelos de características, y así este enfoque de simbiosis JPI + FOP parece prometedor.Item Lagrangian Relaxation for an Inventory Location Problem with Periodic Inventory Control and Stochastic Capacity Constraints(2018) Araya-Sassi, Claudio; Miranda, Pablo A.; Paredes-Belmar, GermánWe studied a joint inventory location problem assuming a periodic review for inventory control. A single plant supplies a set of products tomultiple warehouses and they serve a set of customers or retailers.The problem consists in determining which potential warehouses should be opened and which retailers should be served by the selected warehouses as well as their reorder points and order sizes while minimizing the total costs. The problem is a Mixed Integer Nonlinear Programming (MINLP) model, which is nonconvex in terms of stochastic capacity constraints and the objective function. We propose a solution approach based on a Lagrangian relaxation and the subgradient method. The decomposition approach considers the relaxation of different sets of constraints, including customer assignment, warehouse demand, and variance constraints. In addition, we develop a Lagrangian heuristic to determine a feasible solution at each iteration of the subgradientmethod.The proposed Lagrangian relaxation algorithm provides low duality gaps and near-optimal solutions with competitive computational times. It also shows significant impacts of the selected inventory control policy into total system costs and network configuration, when it is compared with different review period values.