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As governments and non-state actors strive to minimize global warming, a primary strategy is the decarbonization of power systems which will require a massive increase in renewable electricity generation. Leading energy agencies forecast a doubling of global hydropower capacity as part of that necessary expansion of renewables. While hydropower provides generally low-carbon generation and can integrate variable renewables, such as wind and solar, into electrical grids, hydropower dams are one of the primary reasons that only one-third of the world’s major rivers remain free-flowing. This loss of free-flowing rivers has contributed to dramatic declines of migratory fish and sediment delivery to agriculturally productive deltas. Further, the reservoirs behind dams have displaced tens of millions of people. Thus, hydropower challenges the world’s efforts to meet climate targets while simultaneously achieving other Sustainable Development Goals. In this paper, we explore strategies to achieve the needed renewable energy expansion while sustaining the diverse social and environmental benefits of rivers. These strategies can be implemented at scales ranging from the individual project (environmental flows, fish passage and other site-level mitigation) to hydropower cascades to river basins and regional electrical power systems. While we review evidence that project-level management and mitigation can reduce environmental and social costs, we posit that the most effective scale for finding balanced solutions occurs at the scale of power systems. We further hypothesize that the pursuit of solutions at the system scale can also provide benefits for investors, developers and governments; evidence of benefits to these actors will be necessary for achieving broad uptake of the approaches described in this paper. We test this hypothesis through cases from Chile and Uganda that demonstrate the potential for system-scale power planning to allow countries to meet low-carbon energy targets with power systems that avoid damming high priority rivers (e.g., those that would cause conflicts with other social and environmental benefits) for a similar system cost as status quo approaches. We also show that, through reduction of risk and potential conflict, strategic planning of hydropower site selection can improve financial performance for investors and developers, with a case study from Colombia.

Históricamente, la casa se ha constituido como el espacio fundamental que permite la realización de las acti-vidades domésticas, la interrelación familiar y el desarrollo y afianzamiento del yo personal. Diversos autores concuerdan que durante el siglo XX suceden las mayores alteraciones en las estructuras sociales, entornos de ciudades y en la vivienda y sus espacios (Cañar & Torres, 2018); convirtiéndose esta, en el laboratorio de experi-mentación teórico y de aplicación práctica de los modernos estilos de vida (Añón, 2013). En el Ecuador, las trans-formaciones sociales, económicas y políticas de inicios de siglo, se dieron paralelamente a las transformaciones tecnológicas y energéticas, las cuales con mayor o menor demora llegaban a Cuenca. La presente investigación plantea estudiar la modernización de la casa burguesa en Cuenca, a partir de la identificación y análisis de las estrategias proyectuales aplicadas, en la casa Peña (1954) y la casa Vázquez (1962), por el Arq. Cesar Burbano Moscoso. Estas viviendas se caracterizaron por la innovación y búsqueda de una nueva manera de habitar, asu-miendo los cambios que la ciudad exigió a mediados del siglo XX. En los dos casos se evidencia como la tipología tradicional de casa con patio interior, organizada centralmente y alineada y conectada a la calzada, se invierte y muta en una tipología radicalmente contraria, compuesta por construcciones aisladas y retiradas de la calle, modificando así las relaciones, internas de la casa y con la ciudad. El estudio explora procesos arquitectónicos, enfocando el interés en reconocer criterios y valores que provienen de las obras, así como elementos arquitectónicos y urbanos de un momento particular de la arquitectura cuencana.

Climate change induced extreme weather events will increase in intensity and frequency, leading to longer and widespread electricity outages. As an example, Winter Storm Uri in Texas left over 4.5 million customers without power between 14 and 18 February 2021. The social justice consequences of these events remain an outstanding question, as outage data are, typically, only available at the county level, obscuring detailed experiences. We produce a first-of-its-kind unique spatially resolved dataset of interruptions using satellite data on nighttime lights to track blackouts at the census block group (CBG) level. Correlating this dataset with demographic data reveals that minority CBGs were 1.5–3 times more likely to suffer from interruptions compared to predominantly white CBGs, whereas income status was positively correlated with the likelihood of interruption. The presence of critical facilities—including police and fire stations, hospitals, and water treatment facilities—in a CBG reduced the chances of interruptions by around $16\%$ , a small difference that does not otherwise explain the disparity among communities. We suggest explanations, test a subset of them, and propose further work needed to explain what drives these disparities.

Load Serving Entities (LSEs) can procure electricity from their owned generation or purchase it on bilateral or organized markets. Electric utility procurement decisions have important implications for rates, resource adequacy, environmental impacts, and LSE cost recovery. However, there is little or no research on trends of utility procurement practices—or the role of wholesale market transactions. This paper leverages information from the U.S. Department of Energy's Energy Information Administration, Berkeley Lab's Resource Planning Portal, and structured interviews with regulatory and utility staff. We find that use of market transactions to meet electric energy needs has been increasing across U.S. LSEs. The reasons for this trend include a general stagnation in building owned resources, a preference towards contracting renewable energy resources to meet RPS targets, and the lower relative cost of wholesale market electricity. Results suggest resource adequacy obligations may drive preferences for asset ownership more than a profit incentive. We also recommend improving the planning to procurement connection by incorporating operational constraints of market transactions within planning processes. These results provide insights on key issues in electric utility procurement that could improve overall market efficiency and identify practices that stakeholders should consider incorporating into their long-term capacity planning processes.

ABSTRACT The construction of enterprise context models, a fundamental tool for the design of modern information systems, is usually a cumbersome task, largely as a consequence of the lack of communication between administrative staff and technical consultants in charge of its construction. In order to make this task easier, previous works proposed the reuse of context elements identified in various industrial cases, which have been packaged and stored in a catalog specifically designed for this purpose. The authors propose to go one step further, using semantic technologies to exploit the catalog, storing its content in a semantic repository designed to support the construction of context models. In order to construct the repository, NeOn ontology was adopted to develop a network ontology which integrates different domains and their vocabularies, based on different scenarios that allows the capturing of the requirements, reuse and enrichment of ontologies. Keywords: DHARMA Method, NeOn methodology, network ontologies, systems architecture, information systems, istar. RESUMEN La construcción de modelos del contexto empresarial, herramienta fundamental para el diseño de sistemas de información modernos, es generalmente una tarea difícil de conducir, en gran medida debido a la falta de comunicación entre los interesados de la parte administrativa y los consultores técnicos encargados de su construcción. Con el fin de facilitar esta tarea, en trabajos previos hemos propuesto la reutilización de elementos de contexto identificados en diversos casos industriales, los cuales han sido empaquetados y almacenados en un catálogo específicamente diseñado para este propósito. En este artículo proponemos ir un paso adelante, utilizando tecnologías semánticas que permitan explotar el catalogo, almacenando sus contenidos en un repositorio semántico específicamente diseñado para soportar la construcción de modelos de contexto. Para la construcción del repositorio se ha utilizado la metodología NeOn, que permite desarrollar una red de ontologías que integre distintos dominios y sus vocabularios, en base a distintos escenarios que permiten la captura de requerimientos, la reutilización y el enriquecimiento de ontologías. Palabras clave: Método DHARMA, metodología NeOn, red de ontologías, arquitectura de sistemas, sistemas de información, istar.

RESUMEN La evaluación de la calidad de un producto de software juega un papel fundamental tanto en la selección de componentes de software, como en la valoración de un producto resultante de un proyecto de desarrollo. Los Modelos de Calidad del Software (QMs), son artefactos específicamente diseñados y construidos para apoyar en estos procesos. En este trabajo resume el proceso de aplicación de la técnica de Revisión Sistemática de la Literatura, utilizada para actualizar el estado del arte en relación a QM, levantado en un proceso previo realizado en 2007, con el objeto de incluir los trabajos relacionados que han sido publicados entre el 2007 y 2014. El estudio se enfoca los elementos estructurales, propiedades, métodos de construcción y aplicaciones para las cuales han propuestos los QM en este periodo. Palabras clave: Modelos de calidad de software, QMs, revisión sistemática de la literatura, SLR. ABSTRACT Quality evaluation of a software product plays an important role both, in the selection of software components and quality assessment of the deliverables resulting from a software development project. Software Quality Models (QMs) are artifacts specifically designed and constructed to support these activities. This paper summarizes the process of application of a Systematic Literature Review, leaded to update the State of the art in relation to QM resulting from a previous process carried out in 2007, in order to identify and include related works that have been published between 2007 and 2014. The study focuses on the structural elements, properties, construction methods and applications for which QM have been used in this period. Keywords: Software quality models, QMs, systematic literature review, SLR.

RESUMEN La construcción de modelos del contexto empresarial, herramienta fundamental para el diseño de sistemas de información modernos, es generalmente una tarea difícil de conducir, en gran medida debido a la falta de comunicación entre los interesados de la parte administrativa y los consultores técnicos encargados su construcción. Con el fin de facilitar esta tarea y disminuir los errores al momento de construirlos, este artículo propone la reutilización de elementos de contexto identificados en diversos casos industriales, los cuales han sido empaquetados y almacenados en un catálogo específicamente diseñado para este propósito. Palabras clave: Modelos de contexto, notación i*, actores genéricos, dependencias genéricas, método DHARMA. ABSTRACT Building enterprise context models, an essential tool to design today’s information systems, is generally a cumbersome task, mainly due to the lack of communication between the administrative stakeholders and technical consultants responsible of their construction. In order to facilitate this task and reduce mistakes on their construction, this paper proposes the reuse of context elements identified in several industrial cases, which have been packaged and stored in a catalogue specifically designed for this purpose. Keywords: Context models, i* notation, generic actors, generic dependencies, DHARMA method.

RESUMEN Las redes sociales digitales han sido ampliamente estudiadas como medios de comunicación modernos que se encuentran en constante evolución. A más de facilitar la comunicación, estas redes proporcionan a sus usuarios una serie de servicios y aplicaciones de utilidad p.e. acceso a noticias, juegos etc. El uso de estos medios por parte personas de la tercera se ha visto restringido por factores tales como: limitado acceso a Internet, costos de equipamientos y falta de entrenamiento; pero fundamentalmente a aspectos generacionales que los convierten en migrantes digitales. El objetivo de la siguiente revisión sistemática de literatura es identificar cuales redes sociales son las más utilizadas por personas de la tercera edad, así como sus hábitos de uso de las mismas. Se espera que los resultados de este estudio establezcan las bases para plantear estrategias futuras que faciliten la adopción y uso de redes sociales digitales por parte de este importante segmento de la población. Al final, se evidencia que existen estudios relevantes que identifican las redes sociales más utilizadas y las aplicaciones para las que son utilizadas por parte de usuarios de la tercera edad, pero que describen de manera muy limitada sus hábitos de uso. Adicionalmente, ninguno de estos estudios ha sido realizado en Ecuador. Palabras clave: Personas de la tercera edad, redes sociales digitales, hábitos de uso. ABSTRACT Digital social networks have been widely studied as modern media that are constantly evolving. In addition to facilitating communication, these networks provide their users with a range of useful services and applications, i.e. news access, games, etc. The use of these social media by the elderly has been restricted by factors such as: limited access to the Internet, equipment costs and lack of training; but mainly due to generational aspects that make them digital migrants. The objective of this systematic literature review is to identify which social networks are most used by the elderly, as well as their usage habits. The results of this study are expected to establish the basis for future strategies that facilitate the adoption and use of digital social networks by this important segment of the population. It is evident that there are relevant studies that identify the most used social networks and the applications for which they are used by elderly users, but which describe in a very limited way their usage habits. Additionally, none of these studies have been conducted in Ecuador. Keywords: Elderly people, digital social networks, usage habits.