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Rural areas in developing countries have the highest concentrations of unelectrified communities. There is a clear link between electricity consumption and the Human Development Index, as highlighted by the 7th Development Goal of the United Nations. Estimating the energy needs of the previously nonelectrified population is imprecise when designing rural electrification projects. Indeed, daily energy demand and peak power assessments are complex, since these values must be valid over the project’s lifetime, while tight budgets do not allow for the systems to be oversized. In order to assist project promoters, this study proposes a fuzzy mixed integer linear programming model (FMILP) for the design of wind–PV rural electrification systems including uncertainty in the demand requirements. Two different FMILP approaches were developed that maximized the minimum or the average satisfaction of the users. Next, the FMILP approaches were applied to six Latin American communities from three countries. Compared with the deterministic MILP (where the energy and peak power needs are considered as specific values), the FMILP results achieved a better balance between the project cost and the users’ satisfaction regarding the energy and peak power supplied. Regarding the two approaches, maximizing the users’ minimum satisfaction obtained globally better solutions., Postprint (published version)

Many countries are still facing a common hurdle: last-mile rural electrification. Great skill is required to face this challenge, which generally involves the most isolated, inaccessible and complex regions. Many Latin American countries have already undertaken universal access to energy schemes and have built an experience base that, if shared, can add a wealth of knowledge to facilitate the implementation of future initiatives. In this regard, this work evaluates the sustainability of the main electrification initiatives developed in Brazil and Venezuela, by performing an ex-post comparative multicriteria evaluation on 18 quantitative and qualitative social, institutional, economic, technical and managerial indicators. Eight discussion threads are drawn from the programs’ design and implementation strategies and outcomes. The main insights are: the suitability of renewable-based distributed energy resources for covering last-mile rural electrification; the effectiveness of a private context for the development of the technological market and the creation of policy instruments; and the effectiveness of a public context to implement a greater diversity of technological solutions focused on improving social well-being. The lessons learned aim to guide rural electrification promoters and decision makers in developing more sustainable and successful last-mile electrification initiatives., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Postprint (published version)

New forms of consumption, including online streaming, have interfered with film exhibition, promoting important changes. These services need to generate significant traffic and a look for a wide range of home subscribers to provide them with an extensive catalogue of movies. The domestic confinement in almost all countries caused by COVID 19 has led the internet to break historical traffic records. Cinemas are no longer the only place where a film can be shown. The novelty of films is the main factor that convinces viewers to pay for a cinema ticket. The exhibitor must pursue excellence and offer a truly superior experience at a reasonable price, because of the limited budget for leisure activities. This research uses Structural Equation Modelling (SEM) to carry out an empirical analysis on the results of a questionnaire with a focus on the factors influencing the preference for watching films at a cinema, Peer Reviewed, Preprint

Rural electrification should plan the multi-stage implementation of electrification systems considering different distribution options (national grid extension and decentralized off-grid systems) with different energy sources (photovoltaic, wind, diesel, etc.). Most of the existing planning assessment tools search for a static final design and only consider economical and technical criteria, although social and environmental issues have proven essential in ensuring long-term sustainability. In this context, the objective of this paper is to investigate and define how different actions of electricity extension in a region can be gradually organized to maximize the region’s overall satisfaction, and which technology options for electricity generation and distribution should be promoted on a regional scale according to economic, technical, socio-institutional and environmental criteria. The obtained solution defines, at each planning stage, to which communities should electricity access be extended and which configuration and sources are used in each community in order to maximize the total satisfaction of the region. This total satisfaction is calculated by means of multicriteria indices that evaluate the energy provided and the suitability of the chosen system designs according to stakeholders’ opinions (experts, promoters, users, among others). A mixed-integer linear programming (MILP) model is developed to solve the regional multi-stage planning. The model is validated with a computational experiment of 540 randomly generated instances; the results highlight its efficiency. Finally, it is applied to solve a case study of 544 real non-electrified communities in Plateau State (Nigeria) calculating two electrification plans (with a more and less budget-constrained scenario) which are compared with the currently available one. The results show that the proposed new plans significantly increase the total satisfaction obtained in the electrification of the region. The co, Peer Reviewed, Postprint (published version)

Access to electricity for the rural and indigenous population of Ecuador’s Amazon Region (RAE) is considered a critical issue by the national authorities. The RAE is an isolated zone with communities scattered throughout the rainforest, where the expansion of the national grid is not a viable option. Therefore, autonomous electrification systems based on solar energy constitute an important solution, allowing the development of indigenous populations. This work proposes a tool for the design of stand-alone rural electrification systems based on photovoltaic technologies, including both microgrid or individual supply configurations. This tool is formulated as a Mixed Integer Linear Programming model including economic, technical and social aspects. This approach is used to design electrification systems (equipment location and sizing, microgrid configurations) in three real communities of the RAE. The results highlight the benefits of the developed tool and provide guidelines regarding RAE’s electrification., Peer Reviewed, Postprint (published version)

© 2022. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0, This article focuses on the Mixed-Model Assembly Line Balancing single-target problem of type 2 with single-sided linear assembly line configurations, which is common in the industrial environment of small and medium-sized enterprises (SMEs). The main objective is to achieve Algorithmic Transparency (AT) when using Genetic Algorithms for the resolution of balancing operation times. This is done by means of a new matrix methodology that requires working with product functionalities instead of product references. The achieved AT makes it easier for process engineers to interpret the obtained solutions using Genetic Algorithms and the factors that influence decisions made by algorithms, thereby helping in the later decision-making process. Additionally, through the proposed new matrix methodology, the computational cost is reduced with respect to the stand-alone use of Genetic Algorithms. The AT produced using the new matrix methodology is validated through its application in an industry-based paradigmatic example., Peer Reviewed, Postprint (published version)

Making a decision usually means selecting one from different alternatives to solve a problem according to a set of criteria. Multicriteria analysis usually offers a quantitative approach to ease decision-making by ranking the alternatives. However, uncertainty can arise when rating the importance of criteria and the adequacy of each alternative for each criterion, due to two factors: first, answers are usually expressed in linguistic terms that do not have a unique quantification; and second, there might be a lack of confidence in the response. Most multicriteria procedures combine fuzzy numbers and linguistic scales to deal with the first factor, but underestimate confidence issues. In this context, this work develops a Methodology for Integrated Multicriteria Decision-making with Uncertainty (MIMDU), which considers both factors of uncertainty. MIMDU is structured in three phases: (1) a novel procedure based on fuzzy rating scales to model uncertain opinions; (2) a fuzzy formulation of the compromised ranking method to rank the alternatives; and (3) a systematic procedure for results’ interpretation comparing a crisp ranking (without uncertainty) and a fuzzy-based ranking (with uncertainty). The methodology is illustrated with a generic example case, aiming to prove its potential application in any sector. Results show that MIMDU helps decision-makers to choose the most reliable alternative, since significant differences in ranking with and without uncertainty can be addressed. A sensitivity analysis is carried out to bare the effect of confidence in the alternatives evaluation, concluding that worse rankings are obtained for alternatives that are less confidently evaluated. A final comparison with the standard fuzzy VIKOR method shows MIMDU’s major preciseness in modelling non-confident opinions and providing more useful and complimentary information to better assist decision-making., Peer Reviewed, Postprint (author's final draft)

En els darrers anys les vendes de Vehicles Elèctrics (VE) han experimentat un increment considerable. Si ens fixem només en Europa, les vendes de cotxes elèctric i híbrids endollables, fins a finals d’octubre de 2019, es van incrementar per sobre del 39% respecte les vendes del període Q1-Q3 de l’any anterior, tot i que a Espanya aquest increment va ser només del 6%, Postprint (author's final draft)

Isolated small-scale renewable energy projects are a suitable option to provide access to electricity in rural areas. In such projects, establishing a suitable management model is a key issue for ensuring sustainability. The management models can be classified according to the ruling institution: government, municipality, private institution, microenterprise or cooperative. Also, they may differ on sensitive features, such as the systems' ownership, level of users' participation, responsibility for systems operation and maintenance, users’ involvement in systems installation processes and administration of tariff payments. Existing literature lacks of a comparative study highlighting the strengths and weaknesses of each kind of management model and their contribution to achieve technical, economic, social, organisational and environmental sustainability. To fill this gap, this study analyses and compares the impact of different management models through a number of case studies in Peru, Ecuador and Bolivia after 4 years of on-site work. Final general recommendations are given as results to strengthen all sustainability dimensions: among them, realise comprehensive training programs to enhance local maintenance capabilities; reach agreements with final electricity users to set a fair and affordable tariff rate; and incentivize population involvement and self-organisation to rise a sense of ownership. Such aspects are more completely fulfilled by management models based on microenterprises and cooperatives, due to its decisively higher community engagement, and should be incentivized by policy makers in the region., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.1 - Per a 2030, garantir l’accés universal a serveis d’energia assequibles, confiables i moderns, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el con­junt de fonts d’energia, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.a - Per a 2030, augmentar la cooperació internacional per tal de facilitar l’accés a la investigació i a les tecnolo­gies energètiques no contaminants, incloses les fonts d’energia renovables, l’eficiència energètica i les tecnologies de combustibles fòssils avançades i menys contaminants, i promoure la inversió en infraestructures energètiques i tecnologies d’energia no contaminant, Postprint (published version)

The problem of balancing parallel assembly lines with multi-line stations have recently aroused great interest. In this type of lines, it is usual to work with different cycle times, which can cause multi-line stations to have to produce in batches and, thus, buffers may be necessary to locate some units. In this paper, mathematical models are presented to solve the problem of buffer sizing in multi-line stations., Postprint (published version)

In recent years, reductions in the price of photovoltaic panels and batteries have made them profitable. However, the achievement of grid parity, i.e. whether these systems are cheaper than the national grid for residential users, is still being debated. This paper quantifies the proportion of demand that could be covered assuming that solar-battery adoption is decided based on the maximum profit, the maximum autarky with no extra cost or the maximum autarky with limited extra-cost. A simulation model is developed which performs a half-hourly analysis for one year, considering the solar radiation, the consumption pattern and characteristics of equipment. London is examined using a database gathering consumption from 5567 households. In particular, the techno-economic performance of the systems is studied according to different reward schemes (from a non-subsidized to a high compensation one). Results are discussed according to the optimisation strategy: maximising profit, for users seeking economic performance; and maximum autarky, for users willing independence from the grid. Complementarily, the correlation between characteristics of consumption profiles and autarky is analysed. Results show that installations are profitable for a reward of 0.03 £/kWh, under profit maximisation, and can attain 90% autarky. The injection reward is still essential to make batteries profitable., Peer Reviewed, Postprint (published version)

Parallel Assembly Lines with multi-line stations (PALBs) have been widely studied in recent years because PALBs can help improve the efficiency of a production system. However, the need of buffers has not been considered in the PALBP literature. In this study, for the first time in the literature, it is shown and demonstrated the need to consider the use of buffers in this type of line when their cycle times are different. Moreover, the buffer sizing problem in a multi-line workstation is presented and formalized. It is shown that the sequencing and scheduling of the task influences the buffer size. Finally, the designed resolution method is shown: solve a mixed integer linear programming model with a commercial software, with the objective of minimizing the size of the buffers., Peer Reviewed, Postprint (published version)

Purpose: This paper, devoted to the selection of strategic sourcing options as a part of the supply chain design, aims to provide supply chain designers with guidelines for selecting the best strategic sourcing option for each item (i.e., products, modules, parts and services). Design/methodology/approach: The study is based on a review of the literature on sourcing options, buyer-supplier relationships, factors and criteria to select a sourcing strategy as well as the authors experience in this field. Findings: We propose a multi-step process by considering the three dimensions of the strategic sourcing options (who and how many will make the item; in cases of outsourcing, the kind of relationship between buyer and supplier(s); and where the item is to be made) together with the characteristics of the context, demand and product, and the relevant criteria to evaluate them. Originality/value: The main contributions are the review of the factors and criteria for selecting the best strategic sourcing option for each item (i.e., products, modules, parts and services) as well as the guidelines provided for each step of the process., Peer Reviewed, Postprint (published version)

In recent years, solar price drops and regulations have helped residential users to invest in grid-connected photovoltaic (PV) facilities. In Spain, a novel law promotes self-consumption by discounting electricity fed into the grid from the utility bill. However, the performance of PV-based facilities depends on diverse factors. The contribution of this paper is to evaluate the techno-economic performance of such installations for different considerations linked to the Spanish law. A simulation model is used to examine different representative cities, load profiles and alternative objectives: maximising profitability and self-sufficiency. For profit maximisation, results show that load profile variations entail PV size changes up to 5 kWp for the same location, together with huge economic and self-sufficiency differences. In contrast, the solar radiation and compensation rate have a more limited influence. For self-sufficiency maximisation, the economic performance drops close to EUR 0, as benefits are used to double the PV size, buy batteries and reach close to 70% self-sufficiency. Finally, a sensitivity analysis shows a limited impact of the utility tariff and the technology cost on the PV size, but a relevant influence on the benefits. These results can help investors and families to quantify the risks and benefits of domestic self-consumption facilities, Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el con­junt de fonts d’energia, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Postprint (published version)

This paper deals with the problem of scheduling jobs in a parallel flow shop environment without buffers between machines and with sequence-dependent setup times in order to minimize the maximum completion time of jobs. The blocking constraint normally leads to an increase in the maximum completion time of jobs due to the blockage of machines, which can increase even more so when setup times are considerable. Hence, the heuristic to solve this problem must take into account these specificities in order to minimize the timeout of machines. Because the procedures designed to solve the parallel flow shop scheduling problem must deal not only with the sequencing of jobs but also with their allocation to the flow shops, 36 heuristics have been tested in this paper, of which 35 combine sequencing rules with allocation methods while the last one takes a different approach that is more related to the nature of this problem. The computational evaluation of the implemented heuristics showed good performance of the heuristic designed especially for the problem (RCP0) when the setup times are considerable. Furthermore, the evaluation has also allowed us to propose a combined heuristic that leads to good solutions in a short CPU time., Peer Reviewed, Postprint (author's final draft)

Las medidas de confinamiento y reducción de la movilidad impuestas para limitar la expansión del coronavirus tuvieron un impacto positivo en la mejora de la calidad del aire y la reducción del ruido en la ciudad. Del 16 al 22 de marzo, primera semana de confinamiento, en Barcelona se redujo el nivel de dióxido de nitrógeno (NO2) un 40 % y en Madrid un 56 %. Muchas ciudades ya habían implementado medidas para disuadir el uso de vehículos privados. Por ejemplo, reduciendo los carriles de circulación o implementando zonas de bajas emisiones que limitan la circulación a los vehículos más contaminantes. Algunas, además, aprovecharon el periodo de confinamiento para acelerar cambios que ya habían sido diseñados previamente. Un ejemplo lo encontramos en Barcelona, con el proyecto de supermanzanas, diseñado para devolver el espacio público a los peatones, eliminando los coches aparcados en superficie y restringiendo la circulación a vehículos motorizados., Postprint (published version)

Stand-alone electrification systems based on renewable energies are suitable for electrifying isolated rural communities. After some years of operation, their impact on the development of beneficiaries must be evaluated; in order to understand the strengths and weaknesses of each design option and to learn useful lessons for future projects. The literature lacks a unified study that compares the long-term impact on population of several projects combining different options for electricity generation (solar PV, wind and hydro) and distribution (microgrids and individual systems). In this context, this work performs a two-phase assessment of 9 electrification projects combining different systems and located in 6 rural Peruvian communities. First, a qualitative analysis is performed to monitor the progress experienced by the communities, considering previous evaluations carried out shortly after the projects’ implementation. Second, an in-depth analysis of the systems and the development of the communities is quantitatively performed through 28 indicators, evaluating 9 sustainability objectives organised into 4 dimensions: technical, social, economic and environmental. The results show that microgrid projects require and encourage community involvement to promote effective maintenance of the shared equipment. Conversely, individual systems can work for longer periods without as much regular maintenance, but still need an efficient management model to raise funds for repairs. Also, hydro is confirmed as providing continuous and high-quality supply, while solar and wind options allow more flexible designs. In all cases, a well-planned management model is essential for reducing the default rate, organizing effective maintenance and allowing the sustainable development of the community., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.1 - Per a 2030, garantir l’accés universal a serveis d’energia assequibles, confiables i moderns, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el con­junt de fonts d’energia, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.a - Per a 2030, augmentar la cooperació internacional per tal de facilitar l’accés a la investigació i a les tecnolo­gies energètiques no contaminants, incloses les fonts d’energia renovables, l’eficiència energètica i les tecnologies de combustibles fòssils avançades i menys contaminants, i promoure la inversió en infraestructures energètiques i tecnologies d’energia no contaminant, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.b - Per a 2030, ampliar la infraestructura i millorar la tecnologia per tal d’oferir serveis d’energia moderns i sos­tenibles per a tots els països en desenvolupament, en particular els països menys avançats, els petits estats insulars en desenvolupament i els països en desenvolupament sense litoral, d’acord amb els programes de suport respectius, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats::10.2 - Per a 2030, potenciar i promoure la inclusió social, econòmica i política de totes les persones, independentment de l’edat, sexe, discapacitat, raça, ètnia, origen, religió, situació econòmica o altra condició, Postprint (author's final draft)

In the last ten years, there has been a progressive improvement in rural electrification indexes in developing countries, and renewable energies are progressively being integrated into electrification programs. In Cuba, the government has set a target of 700 MW in solar photovoltaic energy by 2030, including rural electrification and off-grid systems. Within this framework, 10,000 modular systems of 300 Wp are being installed in isolated communities. Nowadays, previously diesel-electrified settlements are migrating into renewable energy technologies projects in rural Cuba. The objective of this research is to evaluate the sustainability of these changes in order to identify the implications for other developing countries, taking four different dimensions into account: environmental, technical, socioeconomic, and institutional. For this purpose, the rural communities of Yaguá (diesel-based) and Río Abajo (solar-based) in the province of Sancti Spiritus are visited and studied. Results show that the institutional dimension of sustainability is positive thanks to improvements in energy security and promotion of the Cuban national plan goals. Moreover, results confirm that the energy transition from diesel-based to solar PV is environmentally sustainable in Cuba, but improvements are still necessary in the power capacity of solar modules to strengthen the socioeconomic and technical dimensions., Peer Reviewed, Postprint (published version)

Currently, around 1.1 billion people lack access to electricity, mainly in developing countries. Solar photovoltaic systems can provide electricity, but the design is complex, having to size and site the equipment. Besides, since forecasting consumption habits for newly electrified populations is complex, the estimation of the electricity needs is uncertain. This work addresses, for the first time, demand uncertainty to assist promoters in designing electricity access projects, simultaneously solving the sizing and siting problems, using fuzzy logic. In particular, a mathematical model is proposed, introducing uncertainty through five modelling approaches with different fuzzy logic assumptions: three based on the literature and two novel ones according to the conflicting problem nature (project cost minimisation vs electricity supply maximisation). The five approaches are compared and the new ones obtain solutions achieving a higher satisfaction regarding the cost and electricity supply. Then, the most efficient approach is applied in two Peruvian communities, comparing the solutions with those obtained without uncertainty. The results of the proposal show a better balance between the project cost and the demand supplied. Hence, the proposal can help promoters in developing countries to better design electricity access projects where the demand estimation is complex., Peer Reviewed, Postprint (author's final draft)

This paper deals with the problem of scheduling jobs in a parallel flow shop configuration under the blocking constraint, in which the setup time of machines depends not only on the job to be processed but also on the previously processed one, i.e., there are sequence-dependent setup times. The performance analysis of several iterated greedy algorithms with different initial solution procedures and local searches lets us define an efficient algorithm to minimize the maximum job completion time. Moreover, the computational evaluation showed the efficiency of searching in different neighborhood structures and noted the significant influence of the initial solution. However, contrary to other scheduling problems, starting with a high quality solution does not guarantee better performance of the algorithm., Peer Reviewed, Postprint (published version)

TPM (Total Productive Maintenance), which is part of the Lean Management philosophy, aims to increase the company's productivity by reducing efficiency losses during manufacturing. TPM allows organizations to know the real efficiency with which they are working and the losses of the production process, and with the application of this methodology to improve the efficiency of the equipment and the competitiveness of the company., Peer Reviewed, Postprint (published version)

Brasil es responsable por varios programas de becas en la educación superior, estos patrocinados por el gobierno e instituciones privadas que otorgan becas nacionales e internacionales. Este articulo tiene como objetivo analizar el impacto de los programas de becas de Brasil en la movilidad de estudiantes al extranjero, en particular de los que eligen España para la realización de los estudios superiores. Para este estudio se ha utilizado los datos de los programas de becas del gobierno de Brasil, desarrollados a través del Consejo Nacional de Desarrollo Científico y Tecnológico (CNPq), Ciencia sin fronteras (CsF) y Coordinación de Perfeccionamiento de Personal de Nivel Superior (Capes) y también los datos de la UNESCO - Instituto de Estadística (UIS) series historiales de entradas (inbound) y salidas (outbound). Los resultados han demostrado que los programas de becas de Brasil tienen una importancia muy destacada entre los estudiantes brasileños, este factor tiene una presencia menor en los estudios de la literatura referidos a otros flujos, a pesar de ello, los estudios con estudiantes extranjeros para acudir a España son todavía escasos. En concreto, el flujo de estudiantes desde Brasil hasta España no ha sido estudiado con anterioridad, así que este estudio pretende cubrir esta carencia., Postprint (published version)

The paper assumes that, at the end of the operational period of a Spanish nuclear power plant, an Independent Spent Fuel Storage Installation will be used for long-term storage. Spent fuel assemblies are selected and transferred to casks for dry storage, with a series of imposed restrictions (e.g., limiting the thermal load). In this context, we present a variant of the problem of spent nuclear fuel cask loading in one stage (i.e., the fuel is completely transferred from the spent fuel pool to the casks at once), offering a multi-start metaheuristic of three phases. (1) A mixed integer linear programming (MILP-1) model is used to minimize the cost of the casks required. (2) A deterministic algorithm (A1) assigns the spent fuel assemblies to a specific region of a specific cask based on an MILP-1 solution. (3) Starting from the A1 solutions, a local search algorithm (A2) minimizes the standard deviation of the thermal load among casks. Instances with 1200 fuel assemblies (and six intervals for the decay heat) are optimally solved by MILP-1 plus A1 in less than one second. Additionally, A2 gets a Pearson’s coefficient of variation lower than 0.75% in less than 260s CPU (1000 iterations), Peer Reviewed, Postprint (published version)

Assembly lines are mass production systems which are significant in the industrial production of both standard and customised products. Currently, industrial companies offer several products and it is common for an assembly system to have multiple assembly lines. Parallel assembly lines are multiple lines located in such a way as to allow improvements in the system’s efficiency through the use of common resources. In recent years several research studies have been made on parallel assembly lines. In this paper, we survey the parallel assembly lines balancing problem (PALBP) studies. Moreover, a classification scheme is provided to ease understanding. Finally, the main gaps in the literature are described and future research directions are presented., Peer Reviewed, Postprint (author's final draft)

El negocio cinematográfico se ha visto inmerso en el desarrollo tecnológico y las innovaciones de los últimos años, básicamente la introducción de la tecnología digital, aunque también la globalización o la televisión de pago. Todo ello ha comportado efectos como reducir el ciclo de vida del producto película en la sala de cine o los costes al implantar outsorcing en la producción. Este trabajo analiza el nuevo modelo de negocio cinematográfico según el exhibidor. Las conclusiones se derivan de la valoración de algunos exhibidores cinematográficos de España analizando decisiones como la renovación de proyectores en este cambio de gestión., Peer Reviewed, Postprint (published version)

Electrification with micro-grids is receiving increasing attention to electrify rural areas in developing countries. However, determining the best local supply solution is a complex problem that requires considering different generation technologies (i.e. solar PV, wind or diesel) and different system configurations (off-grid or on-grid). Most existing decision aid tools to assess this design only consider economical and technical issues in a single optimization process. However, social and environmental considerations have been proven key issues to ensure long-term sustainability of the projects. In this context, the objective of this work is to develop a multicriteria procedure to allow comparing electrification designs with on-grid or isolated micro-grids and different tech-nologies considering multiple aspects. This multicriteria procedure is integrated in a two-phased methodology to assist the design of the system to electrification promoters in a structured process. First, different electrification alternatives are generated with an open-source techno-economic optimization model; next, these alternatives are evaluated and ranked with the multicriteria procedure, which considers 12 criteria representing economic, technical, socio-institutional and environmental aspects. The whole design methodology is validated with a real case study of 26 population settlements in Plateau State, Nigeria. Experts in rural electrification within the Nigerian context have been consulted to weight the criteria and particularize their evaluation for the specific case study. Results show that solar PV technology based systems are the most suitable electrification designs for communities in Nigeria, while grid connection feasibility depends on the size of the community and the distance to the closest national grid consumption point., Peer Reviewed, Postprint (author's final draft)

Se presenta un modelo de PLEM para minimizar el coste de almacenamiento de elementos combustibles nucleares gastados en contenedores tipo MPC-32 procedentes de la piscina de una central nuclear. La carga de contenedores se realiza en una sola etapa y en una fecha concreta., En la gestión de residuos de combustible de las centrales nucleares españolas, está previsto activar los almacenes temporales individualizados (ATI) cuando se alcanza la saturación de la piscina destinada a albergar elementos de combustible nuclear gastado durante el periodo de explotación de la instalación; al finalizar dicho periodo, un ATI puede utilizarse como almacén transitorio a corto o largo plazo hasta que el almacén temporal central (ATC) esté disponible. Los elementos combustibles (EC), gastados y ubicados en la piscina de la central nuclear (CN), se seleccionan para su almacenado en seco en contenedores (cápsulas) atendiendo a una serie de restricciones impuestas a cada ATI por el órgano regulador competente en función de los requerimientos que afectan específicamente a los contenedores utilizados (v.gr. la limitación de la carga térmica o el número de posiciones para elementos combustibles). Las características de estas cápsulas condicionan el tiempo mínimo de enfriamiento del combustible en la piscina de la central nuclear y, por consiguiente, el tiempo necesario para completar el vaciado completo de dicha piscina. En este contexto, presentamos un modelo de programación lineal entera mixta (Mixed Integer Linear Programming) con el objetivo de minimizar, en una sola carga de elementos con fecha preestablecida, el coste de utilización de las cápsulas MPC (Multi Purpose Canister) necesarias para reubicar en un almacén ATI el número máximo de elementos de combustible gastado que están disponibles en la piscina de la central en tal fecha. El modelo propuesto se ha explotado mediante el solucionador CPLEX utilizando un caso de estudio inspirado en la realidad de la CN Ascó ubicada a unos 160 km de Barcelona. El método de resolución que proponemos es capaz de resolver instancias con 1500 elementos de combustible, 7 tipos de regiones y 4 tipos de contenedores en un tiempo de CPU inferior a 2 segundos., Preprint

With the rising focus on integrating high shares of renewable energy into energy supply systems, the need to meet the viability of these renewable sources becomes pressing. Apart from storing electricity in electrochemical storage units, the concept of sector coupling could promise to provide the needed flexibility and storage capacities. A strong metric is needed to determine the viability and economic feasibility of different sector-coupled energy systems. This conference study presents an empirical method to develop a list of key performance indicators (KPIs), as a direct adaption of the KPI of the energy system with a single energy vector is not always possible. The list was developed based on a stakeholder workshop within the H2020 research project E-Land. The authors proposed the introduction of three new indicators for the evaluation of sector-coupled energy systems, namely degree of autonomy, levelised cost of energy and degree of sector coupling. A sector-coupled case study is evaluated to validate the performance of such new indicators while proving their utility to better assist decision-making., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.2 - Per a 2030, augmentar substancialment el percentatge d’energia renovable en el con­junt de fonts d’energia, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.a - Per a 2030, augmentar la cooperació internacional per tal de facilitar l’accés a la investigació i a les tecnolo­gies energètiques no contaminants, incloses les fonts d’energia renovables, l’eficiència energètica i les tecnologies de combustibles fòssils avançades i menys contaminants, i promoure la inversió en infraestructures energètiques i tecnologies d’energia no contaminant, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.1 - Per a 2030, garantir l’accés universal a serveis d’energia assequibles, confiables i moderns, Postprint (published version)

Brazil is responsible for various scholarship programs in higher education, these sponsored by the government and private institutions that grant national and international scholarships. The purpose of this article is to analyze the impact of the Brazilian scholarship programs on the mobility of students abroad, particularly those who choose Spain for higher studies. For this study, the data from the Brazilian government scholarship programs, developed through the National Council for Scientific and Technological Development (CNPq), Science without borders (CsF) and Coordination for the Improvement of Higher Level Personnel (Capes), have been used and also data from UNESCO - Statistical Institute (UIS) historical series of entries (inbound) and outlets (outbound). The results have shown that the Brazilian scholarship programs have a very important importance among Brazilian students, this factor has a lesser presence in literature studies referring to other flows, despite this, studies with foreign students to attend to Spain they are still scarce. Specifically, the flow of students from Brazil to Spain has not been previously studied, so this study aims to fill this gap., Postprint (published version)

On-site technology performance evaluations are needed in tropical regions with extreme climatic conditions in order to reinforce electricity access programs based on renewable energy technologies (RET), particularly off-grid small wind technologies (SWT). This research aims to evaluate the technical performance and end-users’ acceptance of two SWT projects in Venezuelan communities located at different altitudes and with different weather conditions: a hot desert climate on the Caribbean coast and dry-winter climate in the Andean mountains. The technical performance is assessed through computer simulations to analyze the electricity demand and the wind resource. End-users’ acceptance is studied from in situ surveys and semi-structured interviews with all beneficiaries. Results show that the flat areas on the north coast have a low wind variability and high wind speeds, while in the mountainous areas the implementation of SWT is limited by the orography’s impact on wind variability. However, the social acceptance of SWT in both communities remains high given the existing relationship between load and production variations., This research was funded by the Spanish Ministry of Science and Innovation (project RTI2018-097962-B-I00) and co-financed by Center for Cooperation Development (CCD) of the Universitat Politecnica de Catalunya e BarcelonaTech (UPC). The authors are very grateful to the Serra Hunter fellowship program of the Generalitat de Catalunya. The work has been possible thanks to the technical collaboration of engineers Angel Lopez V., Leonardo López, G. from PDVSA (Maracaibo, Zulia) and the logistics support of Jack Marquez from PDVSA Industrial (Lagunillas, Mérida). The cooperation of the people from La Macolla (Falcon) and Los Conejos (Mérida) has been extremely important for data collection., Peer Reviewed, Postprint (author's final draft)

Rural electrification has often been promoted to improve women's access to education. However, no studies have been conducted to measure the actual impact of electrification on equitable access to education, qualitatively and quantitatively. This is particularly true when studying rural and indigenous communities in developing countries. The objective of this study is to comprehensively evaluate the impact of electrification on schooling for men and women in La Guajira (Venezuela). Their traditional indigenous rural communities were recently electrified with Renewable Energy Technologies (RET). The study focuses on eight communities that have never had electricity and whose location far from urban settlements limits other social relationships. During a week of total immersion in the fieldwork, the impact on 285 men and 273 women was analyzed through 43 household surveys. The results show that access to primary, secondary, and higher education has increased significantly thanks to coordinated education and electricity policies. School offers similar opportunities for both genders, but a higher percentage of indigenous women take advantage of the opportunity to study beyond the primary level., This research was funded by the Spanish Ministry of Science and Innovation under the project title: “Optimization of Micro networks with Renewable Energies under Uncertainty and Future Network Integration” (OMER-IFIR), RTI2018-097962-B-I00. This research was co-financed by Centre for Cooperation Development (CCD) of the Universitat Politècnica de Catalunya-Barcelona TECH (UPC) under the project title “Development of tools for the evaluation of energy projects”, 2019-B014. This work has been possible thanks to the kind collaboration of the Wayuu people from the Venezuelan Guajira and Fundelec (Venezuela) engineers and technicians., Peer Reviewed, Postprint (author's final draft)

The Universitat Politècnica de Catalunya, UPC-BarcelonaTech (UPC), is currently doing significant steps towards the gender mainstreaming in teaching. Indeed, some years ago some teachers already started individually to introduce gender dimension in their teaching, but it is not until the pilot project named Gender Dimension in Teaching, when a cooperative approach was adopted to reach such mainstreaming in all Bachelor and Master degrees at UPC. Within this project a group of 35 lecturers worked during one semester focusing on the four pillars of teaching (i.e. contents, classroom management, methodology and assessment), which were revised from a gender perspective. Within each pillar, gender issues were identified according to the experienced perception of the project participants. However, uncertainties aroused concerning the reliability of such a perception. Indeed, teachers’ perception might be influenced by stereotypes and prejudices that could alter the identification of gender issues. Hence, it became obvious that more reliable data concerning students’ perceptions was needed. In order to assess this issue, a survey design, test and improvement process was carried out [1]. The first consensual version of the survey was answered by 548 students, 30% of which are women, from 3 Bachelor and 4 Master STEM degrees. The percentage of women was similar to that of the UPC students’ community (27,2% in 2018-2019) but significantly higher than 20,70%, what corresponds to the women’s proportion in the 7 studied degrees. This first comparison already makes evident the different degree of awareness related to gender issues, where women capture more biases than men. Indeed, these differences have been found in most of the survey’s answers related to the students’ observations on attitudes and facts in the frame of UPC degrees. Within the survey, different aspects such as teacher’s gendered attitudes, gendered roles in the teamwork and male and female referents are analysed, This work has been carried out within the framework of the Gender Dimension in Teaching project, at UPC-BarcelonaTech, and GEECCO project that has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 741128. The views and opinions expressed herein are those of the authors and do not necessarily reflect the official point of view of the UPC-BarcelonaTech nor the European Commission., Peer Reviewed, Postprint (published version)

Isolated electrification systems based on renewable energy are a suitable option for providing many rural communities in developing countries with access to electricity. In particular, the design of wind-photovoltaic systems that combine stand-alone and micro-grid systems has proved an efficient but challenging optimization problem. Decision support tools and solution procedures have been proposed in the literature, most of them focused on techno-economic aspects. However, social aspects related to the management of the systems are a key issue for users’ satisfaction and project sustainability. Only one procedure based on mixed integer linear programming takes the management aspects into account, but excessive computing time may be required or no solutions may be found for non-small communities. Thus, a fast procedure is proposed. The validation is carried out by solving 640 instances, randomly generated from real project characteristics. Our procedure always finds a feasible solution in less than 7 s on average; and even for instances with hundreds of possible locations for equipment, the solutions are found in less than 1 min. Moreover, it finds cheaper solutions than those in the literature. Thus, the procedure represents a very efficient process for optimizing the design of electrification projects considering the technical and management constraints., Peer Reviewed, Postprint (author's final draft)

En la gestión de residuos de combustible de las centrales nucleares españolas, está previsto activar los almacenes temporales individualizados (ATI) cuando se alcanza la saturación de la piscina destinada a albergar elementos de combustible nuclear gastado durante el periodo de explotación de la instalación; al finalizar dicho periodo, un ATI puede utilizarse como almacén transitorio a corto o largo plazo hasta que el almacén temporal central (ATC) esté disponible. Los elementos combustibles (EC), gastados y ubicados en la piscina de la central nuclear (CN), se seleccionan para su almacenado en seco en contenedores (cápsulas) atendiendo a una serie de restricciones impuestas a cada ATI por el órgano regulador competente en función de los requerimientos que afectan específicamente a los contenedores utilizados (v.gr. la limitación de la carga térmica o el número de posiciones para elementos combustibles). Las características de estas cápsulas condicionan el tiempo mínimo de enfriamiento del combustible en la piscina de la central nuclear y, por consiguiente, el tiempo necesario para completar el vaciado completo de dicha piscina. En este contexto, presentamos el problema del encapsulamiento en una etapa del combustible nuclear gastado, ofreciendo una formulación y un método de resolución en dos fases. En la primera fase, se utiliza un modelo de Programación lineal entera mixta (MILP-1), cuyo objetivo es minimizar el coste de los contenedores (de diverso tipo) que se requieren para reubicar los elementos disponibles en la piscina de una central nuclear. Para la segunda fase se ha implementado un algoritmo exacto (Algoritmo A1) que, partiendo de una solución de MILP-1, determina asignaciones óptimas de elementos a contenedores regionalizados por limitaciones sobre la carga térmica permitida en cada región. El procedimiento conjunto (MILP-1 más A1) es capaz de resolver óptimamente instancias con 1500 elementos combustibles, 6 tipos de regiones térmicas y 4 tipos de cont, Postprint (published version)

Supply chains (SC) aim to provide products to the final customer at a certain service level. However, unforeseen events occur that impede supply chain objectives. SC Risk has been studied in the literature, providing frameworks and methodologies to manage SC failures. Nevertheless, more efforts are needed to prevent hazardous and disruptive risks and their consequences. These risks must be considered during the process of designing a supply chain. Somemethodological contributions concerning risk in the supply chain network design (SCND) are conceptual frameworks formitigating SC disruptions, which suggest strategies andmeasures for designing robust and resilient SCs. Although such contributions are valuable, they do not indicate how to cope with risk when designing a SC. The main objective of this research is to describe amethodology aimed at including risk considerations into the SCND. Our proposal aims to be, on the one hand, a comprehensive approach that includes a risk identification and assessment procedure in each of the stages of the SCND process and, on the other hand, a tool for decision-making in SC design or redesign processes when SC risks need to be considered. The methodology proposed is an extension of a SCND methodology including risk considerations in order to improve the performance of the supply chains. A case study illustrates how the proposed methodological works, achieving the identification of SC risks already observed in previous works., Peer Reviewed, Postprint (published version)

Se presentan 7 soluciones con programación lineal entera mixta para el almacenamiento monoetápico del combustible nuclear gastado en cápsulas MPC-32 en una central nuclear. Se emplea la instancia de datos Ascó#01_06 y el solver CPLEX para la asignación de elementos combustibles a regiones térmicas., Se presenta en detalle siete soluciones óptimas para la instancia de datos Ascó#01_06 relacionada con la central nuclear Ascó-1 ubicada a 160 km de Barcelona. El procedimiento utilizado para hallar tales soluciones se despliega en dos fases. En la primera fase, se utiliza el modelo MILP-1 descrito en [2], cuyo objetivo es minimizar el coste de los contenedores requeridos para reubicar el máximo número de elementos combustibles disponibles en la piscina de una central nuclear; el modelo MILP-1, implementado en IBM ILOG CPLEX, sirve para concretar la tipología óptima de los contenedores para el vaciado de la piscina, siendo capaz de resolver instancias con 1200 elementos de combustible nuclear, 6 tipos de regiones térmicas y 4 tipos de contenedores en tiempos de CPU inferiores a 0.5 segundos. En la segunda fase, se emplea un procedimiento exacto (Algoritmo A1) que, partiendo de una solución de MILP-1, ofrece asignaciones óptimas de elementos combustibles a contenedores con 32 posiciones agrupadas en dos regiones con limitaciones máximas del calor residual soportable en cada locus (cápsulas MPC-32); el Algoritmo A1 es capaz de ofrecer una asignación óptima en un tiempo de CPU inferior a 0.25 segundos., Preprint

The increase of urbanization is associated to the rise of urban traffic, leading to the growth of environmental and health problems. Cities all over the world are starting to implement driving restrictions to address these issues that challenge commuter mobility, since the public transport, by itself, cannot cover all commuters’ needs. However, other flexible and collective transports such as the emerging ridesharing and shared ride-hailing services might be, in some situations, more convenient means of transport. In this paper, two pilot tests that offered a shared ride-hailing service to commuters were analyzed and compared, with the aim of finding out the usage intention of this transport, as well as the user requirements for a frequent use of the service. The first case study took place during one week in Barcelona, whereas the second was based on the service test of MOIA in Hanover. A quantitative research was conducted to participants of both service tests. Results showed a high intention of use for commuting and leisure trips, and indicated the most important design factors to attract users., Peer Reviewed, Postprint (author's final draft)

Purpose: Emerging shared mobility services are an opportunity for cities to reduce the number of car single trips to both improve traffic congestion and the environment. Users of shared mobility services, such as carsharing, ridesharing and singular and shared ride-hailing services, often need to be customers of more than one service to cover all their transport needs, since few mobility providers offer more than one of these services from a single platform. On the other hand, providers offering these services separately do not optimize costly resources and activities, such as the vehicles or the technology. Hence, the aim of this paper is to find synergies between the different app-based car-related shared mobility services that foster the development of new business models, to increase the profitability of these services. Design/methodology/approach: The research approach is built on the literature of car-related shared mobility services business models, supported by the review of certain outstanding services websites, and face-to-face interviews with users and drivers of these transport services. The analysis is presented by means of the Business Model Canvas methodology. Findings: Based on the synergies found, this paper suggests a few different approaches for services to share some resources and activities. Originality/value: This study identifies the common features of carsharing, ridesharing and singular and shared ride-hailing services to develop more profitable business models, based on providing the services in aggregated form, or outsourcing activities and resources. In addition, the implications of these proposals are discussed as advantages and drawbacks from a business perspective, Peer Reviewed, Postprint (published version)

La Universitat Politècnica de Catalunya, dentro del III Plan de Igualdad de Género 2016-2020, está llevando a cabo diferentes acciones para promover la transversalidad de género en la universidad. El presente artículo expone el trabajo del proyecto Género y Docencia, cuyo objetivo principal es la capacitación del personal académico para la incorporación de la perspectiva de género en la docencia. Este proyecto cuenta con la participación voluntaria de 41 docentes de 8 titulaciones STEM. Su duración, que coincide con el cuatrimestre de primavera de 2019, ha permitido llevar a cabo las estrategias propuestas a lo largo del curso. Los aspectos que se han tenido en cuenta incluyen la relevancia social y de género de las asignaturas, la metodología inclusiva, la gestión del aula y la evaluación. Se ha tenido especial cuidado en la elaboración de indicadores para poder realizar la correcta evaluación del proyecto a su término. Se ha elaborado una herramienta de autoevaluación para el equipo docente y un cuestionario para analizar la sensibilización del alumnado, así como su percepción respecto a la falta de igualdad de género en el ámbito docente., Objectius de Desenvolupament Sostenible::5 - Igualtat de Gènere, Postprint (published version)

Purpose: Once a set of suppliers has been determined, according to criteria of quality, price and reliability, among others, there remains the problem of assigning orders to the selected suppliers, in order to cover the needs at the lowest cost. We consider the case in which the needs of a component for a set of plants should be covered by suppliers with linear piecewise concave cost functions, a lower bound on the order size for the non-zero deliveries and a capacity constraint. The purpose is to design procedures for solving this problem. Design/methodology/approach: With the aim of providing practical tools to solve the problem of assigning orders to suppliers with linear piecewise concave costs, two mixed integer linear programs are proposed. Findings: The two MILP models are compared through an extensive computational experiment. This shows that both models, with a slight advantage for one of them, can be solved within a very short time, even when the dimensions of the instance largely exceed those that can occur in real cases. Originality/value: The paper proposes novel models that can be used to solve the problem to optimality in reasonable times and with standard optimization software., Peer Reviewed, Postprint (published version)

This paper addresses the determination of personnel promotion policies in public Higher Education Institutions (HEI) considering aspects such as worker's promotion rules, hiring and laying off, workforce diversity and budget constraints. The problem is formulated as a Mixed Integer Linear Program. The objective of the proposed optimization model is not only expressed in economic terms but also addressing the achievement of a preferable staff composition and service level. The model is formulated generally, hence it can be useful for different types of universities taken into account their specificities and characteristics. Specifically, this paper addresses the problem of finding the relationship between economic resources for workers'promotion and the pursued preferable staff composition. The model is applied to a real case, in which several analyses are performed under different scenarios characterized by possible trends in the available budget and the demand. The analyses are for different workforce structures, which reflect different academic and personnel policies. The results address the performance of the proposed model in achieving the preferable structure and also on how promotions --and associated expenditures--, are for young researchers and experienced personnel according to each considered scenari, Peer Reviewed, Postprint (author's final draft)

El artículo parte del hecho de que en las principales calles comerciales de las ciudades turísticas europeas se implantan establecimientos comerciales con una oferta comercial de lujo, de lujo asequible y de “mass market”. Posteriormente se define y justifica el concepto “Ejes Comerciales Prime” como aquellas calles comerciales con los precios de alquiler de los locales comerciales más elevados de la ciudad y por tener máxima demanda turística y tráfico peatonal. En el caso de Barcelona, las calles que cumplen los criterios anteriores son Passeig de Gràcia y Av. Portal de l’Àngel. Asimismo, en la investigación se constata que el precio de alquiler de los locales comerciales impacta en la cuenta de explotación de los establecimientos comerciales a través de la tasa de esfuerzo, y además impacta también en la rentabilidad de los inversores de locales comerciales en dichos ejes comerciales Prime. Por primera vez en la literatura científica, se analiza el impacto del mercado inmobiliario de locales comerciales en la articulación de la oferta comercial de los ejes comerciales Prime denode las principales ciudades turísticas europeas, provocando una concentración sectorial, empresarial y de la propiedad. El análisis se centra en la ciudad de Barcelona., Postprint (published version)

Shared ride-hailing transportation is discreetly emerging in cities all over the world with the purpose of decongesting cities, offering a similar comfort and convenience of the private car, and this way, filling the gap between the cities’ bus services and the regular taxi services. Hence, the aim of this research is to detect the main factors that should be taken into account for the service design of shared ride- hailing transportation, as well as to compare this mean of transport with the bus and taxi services. The research was conducted through, first, an analysis of shared ride-hailing services business model. Then, a quantitative research was conducted to users of a small-scale one-week pilot in Barcelona. The results show that factors related to price and travel times are more important from a user perspective than the ones related to comfort, such as the walking distance to the pickup point or the comfort provided by the vehicle. Furthermore, results indicate the intended use of participants of a potential future shared ride-hailing service in different use cases, Postprint (author's final draft)

Purpose: The aim of this study is to analyse the prevalence of the staffing policies associated with the characteristics of the two basic types of organisational configurations identified by Institutional theory (Professional Partnership and Managed Professional Business), or conversely, if they have been evolving as a consequence of contextual factors and trends. Design/methodology/approach: Exploratory research was performed through the case study method. Six case studies were conducted in Spanish affiliates of leading multinational management consulting firms. Findings: Our analysis revealed that the staffing policies and practices of the companies differ significantly. It was further deduced that the origin of companies and the practice of activities other than business consulting could influence their staffing policies. It is concluded that mixed models do exist nowadays and that the origin of companies largely determines their policies. Research limitations/implications: Cultural factors among countries could influence HRM policies and practices. Furthermore, the size of companies could determine (or limit) the implementation of certain staffing policies. The study could be extended to a sample of consulting companies of various sizes and countries to enrich the results Practical implications: For HR managers, knowing the staffing policies at these major companies is a benchmark of HRM effectiveness to be applied to their own companies. In particular, these cases are relevant for other knowledge intensive organizations. Originality/value: The paper provides current empirical evidence on the HRM staffing policies of leading consulting firms and their evolution, Peer Reviewed, Postprint (published version)

In this paper an algorithm for solving the Optimal Power Flow problem for multi-terminal DC networks based on the gradient method is proposed. The aim is seeking the optimal point subject to voltage, current and power constraints. The algorithm is described by a continuous-time port-Hamiltonian model, and the inequality constrains are included by the use of barrier functions. The dynamics of the algorithm is studied and stability conditions are obtained. Finally, the method is used for the offshore wind integration grid in the North Sea and the interconnection with the network dynamics is tested by means of numerical simulations., Peer Reviewed, Postprint (author's final draft)

Shared ride-hailing services are discreetly emerging in cities all over the world, with the purpose of providing a transport service more flexible than the public bus and cheaper than the regular taxi. Hence, it is important to identify and include the relevant and key fa ctors of such a service to ensure its success. The aim of this study was to investigate the utility of a commu ting on-demand shared ride-hailing service and determine the design factors for an appropriate ser vice from the users’ perspective. During one week, a pilot of a shared ride-hailing service to commute f rom the city centre of Barcelona to the most western district of the city was conducted. Although the s ample used in this study was modest in scale, it enabled to draw preliminary conclusions. Users valued very positively the comfort provided but they would not pay more than the double of the price of the public transport. This indicates that despite having a high number of users, such a low price could c omplicate the profitability of the service unless it was partially subsidized., Postprint (author's final draft)

In 2016, 1,100 million people lack access to electricity, mainly in developing countries in Africa, Asia and South America. In these countries, there is a large potential for hydroelectric production through off-grid microgrids, although not fully exploited. This work assesses the long-term sustainability of off-grid microhydro projects operating in rural indigenous communities. More specifically, four sustainability dimensions are analyzed: environmental, technical, socioeconomic and institutional, and specific indicators are proposed for each one. In particular, 6 micro-hydroelectric power plants in southern Venezuela are used as case studies. The data gathering includes surveys, technical visits and interviews with technicians, engineers and beneficiaries. Results show that the institutional dimension and, in particular, alignment between involved institutions has been fundamental for the long-term sustainability. Indeed, appropriate institutional alignment is the key to strengthening the impacts on: (i) the environmental dimension, minimizing emissions and impacts on local ecosystems; (ii) the technical dimension, improving adequacy and reliability of technologies; and (iii) the socioeconomic dimension, making efficient use of electricity to enhance education, health and productivity. Lessons learned and conclusions of this research can significantly contribute to improve future projects, in particular to the 22 included in the electrification plans of Venezuela in coming years., Peer Reviewed, Postprint (author's final draft)

The newspapers must be printed each night in a very short time, in order to deliver them next morning. A printing plant must perfectly design the production, in which some manual operations as the supplement insertion are critical. The main concerns about this manufacturing step are to determine ergonomically the maximum capacity to setup and feed the line by the workers and improve the knowledge on the input conditions of each supplement. A decision support system to determine the number of hired workers needed for the manual insertion (setup and feeding) was developed for a printing plant. It takes into account the supplement characteristics, ergonomic issues and the production rates. A linear program has been defined and some variants have been studied. The new system led to a 13% increase in productivity, a reduction in cost overruns and an important reduction in labor costs. The system may be used for a short-term staff planning, Peer Reviewed, Postprint (author's final draft)

This study assesses the development process of a tool to measure students’ perceptions of gender mainstreaming in STEM (Science, Technology, Engineering and Mathematics) studies. Within the framework of a pilot project named Gender Dimension in Teaching implemented at the Universitat Politècnica de Catalunya · BarcelonaTech (UPC), a group of 35 teachers worked during one semester on how to introduce the gender perspective in their teaching. This aim is especially relevant when considering STEM studies, since they have traditionally been defined as gender-neutral when, in fact, they are gender-blind. The teachers that participate in the project cover a wide range of STEM studies, including Architecture, Civil Engineering, ICT Systems Engineering, Naval Systems and Technology Engineering, Aerospace Systems Engineering, Applied Telecommunications and Engineering Management, Industrial Engineering and Environmental Pathways for Sustainable Energy Systems. The project is part of the III Gender Equality Plan at the UPC and is supported by GEECCO project, which receives funding from the European Union's Horizon 2020 Research and Innovation programme. The Gender Dimension in Teaching project focuses on the four pillars of teaching (i.e. contents, classroom management, methodology and assessment), which were revised from a gender perspective. Within each pillar, gender issues were identified according to the experienced perception of the project participants. These gender issues included, for instance, gender differences in classroom participation, the stereotypical roles adopted in teamwork activities, the use of female references as models for students, the adoption of a gender-inclusive language by both teachers and students, the use of stereotypes in teaching materials, gender bias in assessment, etc. However, uncertainty aroused concerning the reliability of such a perception. Indeed, teachers’ perception might be influenced by stereotypes and prejudices that could alte, Peer Reviewed, Postprint (published version)

In the residential sector, grid parity has been reached or is close to be reached in many countries, which means that the cost of electricity from residential photovoltaic installations is equal to or less than the retail electricity price. However, not all installations are equally profitable. The objective of this paper is to analyze the economic performance of residential self-consumption systems, particularly the effect of electric load profiles in regard to that performance. For this purpose, a simulation model is proposed to perform a comparative analysis of the profitability of different configurations of a grid-connected, residential solar system. The model is applied to several differentiated load profiles, as well as to different configurations of photovoltaic panels and batteries. The analysis shows the impact of different load profiles on self-consumption, autarchy and, ultimately, the grid parity of the installation., Postprint (author's final draft)