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Ítem The role of regional tax autonomy, firm size, and business groups in tax avoidance: evidence from Spain(Taylor & Francis, 2024-07-10) Garmendia-Lazcano, Aitor; Baselga Pascual, LauraThis paper investigates the influence of regional tax autonomy, firm size, and business group affiliation on corporate tax burden in a large sample of Spanish firms, including non-listed firms, from 2007 to 2016. Our findings reveal that firms located in tax- autonomous regions exhibit lower effective corporate tax rates (ETR), providing new empirical support for the horizontal tax com-petition theory. Additionally, we identify a positive relationship between firm size and corporate tax burden, aligning with the political cost theory. Furthermore, we find that group-affiliated firms face a higher ETR than independent firms, and that group affiliation attenuates the differences in the tax burden experienced by large and small firms.Ítem Sliding mode control design using a generalized reduced-order fractional model for chemical processes(Elsevier B.V., 2024-12) Gude, Juan José; Di Teodoro, Antonio; Agudelo, D’hamar; Herrera Garzón, Marco Antonio; Rincón, Luis; Camacho, OscarThis article presents a comprehensive study that evaluates the potential advantages of adopting a unified, systematic, and organized general fractional model within the Sliding Mode Control (SMC) design framework. The exploration extends to the model's applicability in a variety of disciplines. Although prior research has utilized SMC and fractional-order systems independently, no previous work has established a mathematical framework that integrates a generic fractional-order SMC model. The study addresses this gap and highlights potential implications for control design and applications in a variety of fields, particularly for chemical processes.Ítem La era de los “golden workers” y los retos de la negociación colectiva en la gestión de la edad en la empresa(Instituto Internacional de Sociología Jurídica de Oñati = The Oñati International Institute for the Sociology of Law, 2024) Serrano Argüeso, MariolaEl envejecimiento de la población en un hecho, y también una preocupación social a nivel mundial. En el ámbito empresarial subyacen dos problemas que han de encontrar su punto de conexión, por un lado, la necesidad que las personas mayores continúen en el mercado de trabajo, por el otro, los prejuicios existentes en la empresa relacionados con las personas mayores. Los llamados planes de diversidad generacional son fundamentales para el mantenimiento de las personas mayores en el mercado de trabajo pero, vistas experiencias anteriores, la negociación colectiva debe ser el ámbito en el que se gesten los mismos, preferiblemente de forma obligatoria, lo que, a día de hoy, no está ocurriendo.Ítem La reincorporación colectiva de las FARC-EP: una apuesta estratégica en un entorno adverso(Fundación CIDOB, 2019) Zambrano Quintero, Magda LilianaContrario a los tradicionales procesos de Desarme, Desmovilización y Reintegración (DDR), que se centran en la individualización de combatientes, las Fuerzas Armadas Revolucionarias de Colombia-Ejército del Pueblo (FARC-EP) optaron por una reincorporación colectiva que combina su conversión a partido político con la puesta en marcha de proyectos productivos colectivos en el marco de la cooperativa Economías Sociales del Común (Ecomún). Pese a ser una apuesta estratégica, los elementos del entorno no han facilitado la materialización de dicho modelo. En este artículo se hace un análisis de los cambios estratégicos, organizacionales y operacionales por los que han atravesado las FARC-EP en su proceso de tránsito a la vida política legal, destacando sus fortalezas y debilidades, así como los desafíos a los que se enfrentan para mantenerse cohesionadas en la legalidad.Ítem La verdad en el exilio: situación de las víctimas del conflicto colombiano en España(Centro Internacional de Estudios Superiores de Comunicación para América Latina (CIESPAL), 2020) Sepúlveda Giraldo, Claudia Alejandra; Zambrano Quintero, Magda LilianaUna de las tareas que enmarcan el tránsito de la guerra a la paz es poner en marcha los mecanismos para garantizar la verdad, justicia, reparación y no-repetición de los hechos de violencia. En Colombia, como resultado de los Acuerdos de Paz con las FARC-EP, se instaló la Comisión para el Esclarecimiento de la Verdad cuya finalidad es construir un relato holístico del conflicto armado. Uno de los elementos novedosos de esta Comisión es que recoge las historias de las victimas en el exterior. Este artículo llama la atención sobre esta cuestión desarrollando la idea de que las personas que se ven forzadas a salir del país por razones del conflicto armado se enfrentan en el exilio a otro tipo de vulneraciones que se suman al acumulado de violaciones de derechos humanos. Para ello, se vale del caso de las personas que llegan a España para salvaguardar sus vidas y a partir de un retrato de su situación se señalan varias de las tensiones a las que se ven abocadas. Hacer explícitas estas vulneraciones contribuye a construir una verdad del exilio que ha sido poco explorada en este tipo de procesos.Ítem Espejos internacionales para la comprensión del tránsito de las FARC-EP a partido político(Universidad de Caldas, 2020) Zambrano Quintero, Magda LilianaLa transformación de grupos rebeldes en partidos políticos es un elemento clave para la sostenibilidad de la paz. Se trata de un proceso complejo en el que intervienen múltiples factores cuyo resultado varía de un caso a otro. Este artículo se pregunta por las condiciones que intervienen para que dicho tránsito a la vida política legal sea más o menos exitosa. Para ello se hace una revisión de literatura de otras experiencias en el mundo que ya han atravesado por esta transición, con el fin de identificar los factores que han influido en la variedad de resultados y extraer de ellos recomendaciones útiles para el reciente caso de las FARC-EP en Colombia.Ítem Null-controllability properties of the wave equation with a second order memory term(Academic Press Inc., 2019-07-05) Biccari, Umberto; Micu, SorinWe study the internal controllability of a wave equation with memory in the principal part, defined on the one-dimensional torus T=R/2πZ. We assume that the control is acting on an open subset ω(t)⊂T, which is moving with a constant velocity c∈R∖{−1,0,1}. The main result of the paper shows that the equation is null controllable in a sufficiently large time T and for initial data belonging to suitable Sobolev spaces. Its proof follows from a careful analysis of the spectrum associated with our problem and from the application of the classical moment method.Ítem Internal control for a non-local Schrödinger equation involving the fractional Laplace operator(American Institute of Mathematical Sciences, 2022-02) Biccari, UmbertoWe analyze the interior controllability problem for a non-local Schrödinger equation involving the fractional Laplace operator (-Δ)s, s ϵ(0 1), on a bounded C1 1 domain RN. We first consider the problem in one space dimension and employ spectral techniques to prove that, for s ϵ [1/2/1), null-controllability is achieved through an L2(ωX (0,T)) function acting in a subset ω Ω of the domain. This result is then extended to the multi-dimensional case by applying the classical multiplier method, joint with a Pohozaev-type identity for the fractional Laplacian.Ítem Null controllability of linear and semilinear nonlocal heat equations with an additive integral kernel(Society for Industrial and Applied Mathematics Publications, 2019) Biccari, Umberto; Hernández Santamaría, VíctorWe consider a linear nonlocal heat equation in a bounded domain Ω ⊂ ℝ with Dirichlet boundary conditions. The nonlocality is given by the presence of an integral kernel. We analyze the problem of controllability when the control acts on an open subset of the domain. It is by now known that the system is null controllable when the kernel is time-independent and analytic or, in the one-dimensional case, in separated variables. In this paper, we relax this assumption and we extend the result to a more general class of kernels. Moreover, we get explicit estimates on the cost of null controllability that allow us to extend the result to some semilinear models.Ítem Dynamics and control for multi-agent networked systems: a finite-difference approach(World Scientific Publishing Co. Pte Ltd, 2019-04) Biccari, Umberto; Ko, Dongnam; Zuazua, EnriqueWe analyze the dynamics of multi-agent collective behavior models and its control theoretical properties. We first derive a large population limit to parabolic diffusive equations. We also show that the nonlocal transport equations commonly derived as the mean-field limit, are subordinated to the first one. In other words, the solution of the nonlocal transport model can be obtained by a suitable averaging of the diffusive one. We then address the control problem in the linear setting, linking the multi-agent model with the spatial semi-discretization of parabolic equations. This allows us to use the existing techniques for parabolic control problems in the present setting and derive explicit estimates on the cost of controlling these systems as the number of agents tends to infinity. We obtain precise estimates on the time of control and the size of the controls needed to drive the system to consensus, depending on the size of the population considered. Our approach, inspired on the existing results for parabolic equations, possibly of fractional type, and in several space dimensions, shows that the formation of consensus may be understood in terms of the underlying diffusion process described by the heat semi-group. In this way, we are able to give precise estimates on the cost of controllability for these systems as the number of agents increases, both in what concerns the needed control time horizon and the size of the controls.Ítem Propagation of one- and two-dimensional discrete waves under finite difference approximation(Springer, 2020-12) Biccari, Umberto; Marica, Aurora; Zuazua, EnriqueWe analyze the propagation properties of the numerical versions of one- and two-dimensional wave equations, semi-discretized in space by finite difference schemes. We focus on high-frequency solutions whose propagation can be described, both at the continuous and at the semi-discrete levels, by micro-local tools. We consider uniform and non-uniform numerical grids as well as constant and variable coefficients. The energy of continuous and semi-discrete high-frequency solutions propagates along bi-characteristic rays, but their dynamics are different in the continuous and the semi-discrete setting, because of the nature of the corresponding Hamiltonians. One of the main objectives of this paper is to illustrate through accurate numerical simulations that, in agreement with micro-local theory, numerical high-frequency solutions can bend in an unexpected manner, as a result of the accumulation of the local effects introduced by the heterogeneity of the numerical grid. These effects are enhanced in the multi-dimensional case where the interaction and combination of such behaviors in the various space directions may produce, for instance, the rodeo effect, i.e., waves that are trapped by the numerical grid in closed loops, without ever getting to the exterior boundary. Our analysis allows to explain all such pathological behaviors. Moreover, the discussion in this paper also contributes to the existing theory about the necessity of filtering high-frequency numerical components when dealing with control and inversion problems for waves, which is based very much on the theory of rays and, in particular, on the fact that they can be observed when reaching the exterior boundary of the domain, a key property that can be lost through numerical discretization.Ítem Multilevel Selective Harmonic Modulation via optimal control(Springer, 2022) Biccari, Umberto; Esteve Yagüe, Carlos; Oroya-Villalta, Deyviss JesúsWe consider the Selective Harmonic Modulation (SHM) problem, consisting in the design of a staircase control signal with some prescribed frequency components. In this work, we propose a novel methodology to address SHM as an optimal control problem in which the admissible controls are piecewise constant functions, taking values only in a given finite set. In order to fulfill this constraint, we introduce a cost functional with piecewise affine penalization for the control, which, by means of Pontryagin’s maximum principle, makes the optimal control have the desired staircase form. Moreover, the addition of the penalization term for the control provides uniqueness and continuity of the solution with respect to the target frequencies. Another advantage of our approach is that the number of switching angles and the waveform need not be determined a priori. Indeed, the solution to the optimal control problem is the entire control signal, and therefore, it determines the waveform and the location of the switches. We also provide numerical examples in which the SHM problem is solved by means of our approach.Ítem A two-stage numerical approach for the sparse initial source identification of a diffusion–advection equation(Institute of Physics, 2023-09) Biccari, Umberto; Song, Yongcun; Yuan, Xiaoming; Zuazua, EnriqueWe consider the problem of identifying a sparse initial source condition to achieve a given state distribution of a diffusion–advection partial differential equation after a given final time. The initial condition is assumed to be a finite combination of Dirac measures. The locations and intensities of this initial condition are required to be identified. This problem is known to be exponentially ill-posed because of the strong diffusive and smoothing effects. We propose a two-stage numerical approach to treat this problem. At the first stage, to obtain a sparse initial condition with the desire of achieving the given state subject to a certain tolerance, we propose an optimal control problem involving sparsity-promoting and ill-posedness-avoiding terms in the cost functional, and introduce a generalized primal-dual algorithm for this optimal control problem. At the second stage, the initial condition obtained from the optimal control problem is further enhanced by identifying its locations and intensities in its representation of the combination of Dirac measures. This two-stage numerical approach is shown to be easily implementable and its efficiency in short time horizons is promisingly validated by the results of numerical experiments. Some discussions on long time horizons are also included.Ítem The design of Datascapes: toward a design framework for sonification for anomaly detection in AI-supported networked environments(Frontiers Media SA, 2024-01-11) Lenzi, Sara; Terenghi, Ginevra; Meacci, Damiano; Moreno Fernández de Leceta, Aitor; Ciuccarelli, PaoloThere is a growing need for solutions that can improve the communication between anomaly detection algorithms and human operators. In the context of real-time monitoring of networked systems, it is crucial that new solutions do not increase the burden on an already overloaded visual channel. Sonification can be leveraged as a peripheral monitoring tool that complements current visualization systems. We conceptualized, designed, and prototyped Datascapes, a framework project that explores the potential of sound-based applications for the monitoring of cyber-attacks on AI-supported networked environments. Within Datascapes, two Design Actions were realized that applied sonification on the monitoring and detection of anomalies in (1) water distribution networks and (2) Internet networks. Two series of prototypes were implemented and evaluated in a real-world environment with eight experts in network management and cybersecurity. This paper presents experimental results on the use of sonification to disclose anomalous behavior and assess both its gravity and the location within the network. Furthermore, we define and present a design methodology and evaluation protocol that, albeit grounded in sonification for anomaly detection, can support designers in the definition, development, and validation of real-world sonification applications.Ítem Perceived quality of a nighttime hospital soundscape(Walter de Gruyter GmbH, 2024-08-01) Lenzi, Sara; Lindborg, PerMagnus; Spagnol, Simone; Kamphuis, Daan; Özcan, ElifThe hospital soundscape is known for high noise levels and a perception of chaos, leading to concerns about its impact on patients, families, professionals, and other hospital staff. This study investigates the relationship between sound, Annoyance, and sleep quality in a multi-patient neurology ward. A mixed-methods approach was employed. Interviews were conducted with medical staff (n = 7) to understand their experiences with sound. Questionnaires and sleep tracking devices (n = 20) assessed patient sleep quality and Annoyance caused by sound events. In addition, listeners (n = 28) annotated 429 nighttime audio recordings to identify sound sources and rate Annoyance level, which we considered the key emotional descriptor for patients. Over 9,200 sound events were analysed. While snoring, a patient-generated sound dominated the nighttime soundscape and was highly rated for Annoyance, and staff-generated sounds such as speech and footsteps were found to contribute more to accumulated Annoyance due to their extended duration. This study suggests that patient sleep quality can be improved by focusing on design interventions that reduce the impact of specific sounds. These might include raising awareness among staff about activities that might produce annoying sounds and implementing strategies to mitigate their disruptive effects.Ítem Re(de)fining sonification: project classification strategies in the Data Sonification Archive(Audio Engineering Society, 2024-09) Lindborg, PerMagnus; Caiola, Valentina; Ciuccarelli, Paolo; Chen, Manni; Lenzi, SaraThis study focuses on a corpus of 445 sonification projects currently available in the Data Sonification Archive (DSA). The DSA develops in a collaborative process that involves researchers and creative communities and has been online since early 2021. Projects are heuristically classified according to several aspects, in particular their intended purpose, targeted users, subject matter, sonification method, and combination of media. In the present study, the authors analyze six curatorial classification strategies, labelled Goal, Method, User, Macro Topic, Micro Topic, and MediaMix, and discuss their definitions and usefulness for the archive. They then introduce two computational classification strategies, respectively based on clustering of music information retrieval of sonification audio and topic modeling of the descriptive texts that accompany DSA projects. Correlation analysis between curatorial and computational classifications, correspondingly sized, showed that the text-based method was more powerful than the audio-based methods. The authors then explored predictive modeling, tentatively achieving results for Goal, Method, and Macro Topic. This points toward the potential for automatic classification to assist in the curatorial management of the archive, as well as for similar repositories. The discussion focuses on how analysis of classification strategies supports a broadening of the definition of sonification, both as theoretical construct and as practice, where the communicative intention of the author, the aesthetic quality of the listening experience, a more explicit focus on narrative patterns, and other emerging aspects within sonification design, are all contributing factors to transitioning the field toward a mass medium for data representation, communication, and meaning-making.Ítem Las nuevas tecnologías en el ámbito laboral: oportunidades y amenazas para la eliminación de la brecha salarial entre mujeres y hombres(Iustel, 2020) Serrano Argüeso, Mariola; Aboitiz Cazalis, MaialenLa reciente incorporación de las nuevas tecnologías en el ámbito laboral está generando cambios de impredecible magnitud, pero existen claros indicios de que la cuarta revolución industrial afectará especialmente a las mujeres e incrementará las desigualdades sociales existentes; entre otras, la brecha salarial entre mujeres y hombres. Este artículo tiene como objeto identificar las amenazas y también las oportunidades que dicha revolución puede generar y formular propuestas para que suponga un avance en la consecución de la igualdad de remuneración entre mujeres y hombres.Ítem Comparative study of emotional facial expression recognition among Prader–Willi syndrome subtypes(John Wiley and Sons Inc, 2024) Perosanz Hidalgo, Ane; López Paz, Juan Francisco; Amayra Caro, Imanol; García Martín, Maitane; Martínez, ÓscarBackground: Prader–Willi syndrome (PWS) is a congenital disease caused by a rare and generally non-inherited genetic disorder. The inability to recognise facial expressions of emotion is an apparent social cognition deficit in people diagnosed with PWS. The main objective of the present study is to compare the ability to recognise emotional facial expression, in both non-contextualised and contextualised scenarios, among the main subtypes of PWS and a control group. Methods: The sample consisted of 46 children divided into three groups: deletion (n = 10), maternal uniparental disomy (mUPD) (n = 13) and control (n = 23). The protocol included the Facially Expressed Emotion Labeling and the Deusto-e-Motion 1.0. Results: The control group recognised facial emotions more accurately and quickly in both non-contextualised and contextualised scenarios than children with PWS, regardless of genetic subtype. Despite no differences being detected between PWS subtypes when non-contextualised scenarios were analysed, in contextualised situations, a longer reaction time was observed in children with the mUPD subtype. Conclusions: This is the first study to assess the ability to recognise emotional facial expressions in contextualised situations among PWS subtypes and a control group. The findings suggest that some of the social cognitive deficits evidenced in children with mUPD PWS may be similar to those in autism spectrum disorder.Ítem Propiedades psicométricas de la versión en castellano del Cuestionario Calidad de Vida Pediátrica Módulo de Impacto Familiar (PedsQL FIM)(Elsevier España, 2023-01) Ortega, Javiera; Vázquez, Natalia; Amayra Caro, Imanol; Assalone, FlorenciaIntroducción: Este trabajo analiza las propiedades psicométricas de la versión en castellano del Cuestionario de calidad de vida pediátrica módulo de impacto familiar (PedsQL FIM) en población argentina. Pacientes y métodos : Se obtuvo una muestra de 232 cuidadores, 108 de niños con enfermedades crónicas (M = 9,54, DE = 4,43) y 124 de niños de población general (M = 12,37, DE = 4,6). Resultados: La validez del instrumento se estudió a través del método de grupos contrastados, encontrando diferencias significativas en la escala total y subdimensiones de la escala (p < 0,01). A su vez, se realizó un análisis factorial exploratorio en el que se encontró un modelo de 8 factores explicando el 74,02% de la varianza total. La confiabilidad fue estudiada a través del coeficiente alfa de Cronbach y se encontró un valor alto de consistencia interna α = 0,95. Conclusiones: El instrumento PedsQL demostró ser una herramienta válida y confiable para estudiar el impacto que tiene una condición pediátrica crónica a nivel de la calidad de vida del cuidador y del funcionamiento familiar.Ítem The emergent role of digital technologies in the context of humanitarian supply chains: a systematic literature review(Springer, 2022-12) Marić, Josip; Galera Zarco, Carlos; Opazo Basáez, MarcoThe role of digital technologies (DTs) in humanitarian supply chains (HSC) has become an increasingly researched topic in the operations literature. While numerous publications have dealt with this convergence, most studies have focused on examining the implementation of individual DTs within the HSC context, leaving relevant literature, to date, dispersed and fragmented. This study, through a systematic literature review of 110 articles on HSC published between 2015 and 2020, provides a unified overview of the current state-of-the-art DTs adopted in HSC operations. The literature review findings substantiate the growing significance of DTs within HSC, identifying their main objectives and application domains, as well as their deployment with respect to the different HSC phases (i.e., Mitigation, Preparedness, Response, and Recovery). Furthermore, the findings also offer insight into how participant organizations might configure a technological portfolio aimed at overcoming operational difficulties in HSC endeavours. This work is novel as it differs from the existing traditional perspective on the role of individual technologies on HSC research by reviewing multiple DTs within the HSC domain.