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Abstract In this paper, a general mathematical model for the dynamic simulation of a single-effect LiBr/water absorption chiller is presented. The model is based on mass and energy balances applied to the internal components of the machine, and it accounts for the non-steady behaviour due to thermal and mass storage in the components. The validation of the mathematical model is performed through experimental data collected on a commercial small-capacity water-cooled unit. Due to the peculiar technology adopted in the real chiller, a special effort was made to identify the appropriate values of the main physical parameters. The validation of the model is based on the values of the water temperature at the outlet of the machine, as no measurement inside the machine was possible; anyway, a consistency analysis applied to the internal parameters is also presented. The agreement between experimental and simulated results is very good, both on a daily and on a seasonal basis.

Les conséquences du changement climatique sont particulièrement aiguës au Kenya, où 80 % des terres sont arides ou semi-arides. Quelle perspective critique et constructive le concept d’habitabilité peut-il offrir dans ce contexte ? Fondé sur un travail de terrain réalisé au Kenya en 2022 et 2023, cet article entend affiner une définition in situ de l’habitabilité, en utilisant exclusivement des données qualitatives issues de deux phases de recherche, complétées par des exercices de vidéo-cartographie. Loin de proposer une lecture positiviste de l’habitabilité, portée par une conception exclusivement mécanique et linéaire des dynamiques de mobilité, cette étude propose de mieux relier l’habitabilité aux pratiques quotidiennes, aux habitudes, aux solidarités, voire aux résistances qui constituent la vie ordinaire des habitants des communautés et des personnes déplacées. L’habitabilité se situerait alors au cœur de l’intrication entre socialité et spatialité, entre social et biologique, qui définit – selon Stanley Cavell – la forme de vie humaine. The consequences of climate change are particularly acute in Kenya, where 80% of the land is arid or semi-arid. What critical and constructive perspective can the concept of habitability offer in this context? Based on fieldwork carried out in Kenya in 2022 and 2023, this article aims to refine an in-situ definition of habitability, using exclusively qualitative data from two research phases, supplemented by video-mapping exercises. Far from proposing a positivist reading of habitability, driven by an exclusively mechanical and linear conception of mobility dynamics, this study proposes to better link habitability to the daily practices, habits, solidarities and even resistances that make up the ordinary lives of community dwellers and displaced persons. Habitability would then lie at the heart of the intricacy between sociality and spatiality, between the social and the biological, which defines – according to Stanley Cavell – “the human form of life.”

Esta dissertação pretende ser um contributo para um conhecimento mais aprofundado sobre a importância do turismo criativo no desenvolvimento de um modelo sustentável de um destino turístico urbano. Deste modo, a dissertação desenvolve-se em três partes. A primeira centra-se numa revisão da literatura mais aprofundada sobre a criatividade e o turismo criativo com um foco específico na sustentabilidade criativa urbana. A segunda e a terceira parte concentram-se no estudo de dois casos. O primeiro, o caso de Barcelona, é um destino turístico que desenvolveu com sucesso o turismo criativo e foi reconhecido internacionalmente como boas práticas de turismo criativo sustentável. O segundo, o caso de Lisboa, é um destino que possui um grande potencial cultural e criativo. A análise observatória do estudo de caso de Barcelona permitiu apresentar uma proposta de modelo geral de turismo criativo e dar pistas a Lisboa em termos das etapas do desenvolvimento do turismo criativo, da gestão e das estratégias. A abordagem desta dissertação foca-se numa metodologia qualitativa, apoiando-se em algumas entrevistas. No que se refere aos principais resultados, descobriu-se que Lisboa apresenta as premissas para um desenvolvimento de turismo criativo. This dissertation intends to be a contribute for a better understanding of the importance of creative tourism in the development of a sustainable model of an urban tourist destination. Thus, the dissertation develops in three parts. The first concentrates on a review of the literature on creativity and creative tourism with a specific focus on urban creative sustainability. The second and the third parts aim to study two cases. The first, the case of Barcelona, is a tourist destination that has successfully developed the creative tourism and was internationally recognized for good sustainable creative tourism practices. The second, the case of Lisbon, is a destination that has a great cultural and creative potential. The observatory analysis of the case study of Barcelona has allowed to present a proposal for a general model of creative tourism and gives clues to Lisbon in terms of the stages of the development of creative tourism, management and strategies. The approach of this dissertation focuses on a qualitative methodology, relying on some interviews. With regard to the main results, it was found that Lisbon presents the assumptions for a development of creative tourism. Orientação: Jorge Mangorrinha

Energy management within microgrids under the presence of large number of renewables such as photovoltaics is complicated due to uncertainties involved. Randomness in energy production and consumption make both the prediction and optimality of exchanges challenging. In this paper, we evaluate the impact of uncertainties on optimality of different robust energy exchange strategies. To address the problem, we present AIROBE, a data-driven system that uses machine-learning-based predictions of energy supply and demand as input to calculate robust energy exchange schedules using a multiband robust optimization approach to protect from deviations. AIROBE allows the decision maker to tradeoff robustness with stability of the system and energy costs. Our evaluation shows, how AIROBE can deal effectively with asymmetric deviations and how better prediction methods can reduce both the operational cost while at the same time may lead to increased operational stability of the system.

Abstract In this work, we intend to solve the equations governing two laminar isothermal or non-isothermal coaxial plane jets with variable density in an ambient fluid at rest in order to study the initial conditions influence (i.e. the nozzles ejection conditions) on the jet characteristic parameters. A finite difference method is developed to solve the dimensionless Navier–Stokes and energy equations resulting from some assumptions. The discussion about the results relates primarily to the concentration core length according to the nozzles thicknesses ratios. The influences of the gas velocity and temperature resulting from the external nozzle are also examined. This made it possible to deduce correlations of practical use between these parameters in order to apply them in engineering processes.

Dans les latitudes tempérées élevées, les ongulés donnent généralement naissance dans une fenêtre temporelle étroite lorsque les conditions sont optimales pour la survie de la progéniture au printemps ou au début de l'été, et utilisent une photopériode changeante pour les conceptions temporelles afin d'anticiper ces conditions. Cependant, dans les basses latitudes tropicales, la variation de la durée du jour est minime et la variation des précipitations rend le cycle saisonnier moins prévisible. Néanmoins, plusieurs espèces d'ongulés conservent des pics de naissance étroits dans de telles conditions, tandis que d'autres montrent que les naissances se propagent assez largement tout au long de l'année. Nous avons étudié comment la variation des précipitations d'une année à l'autre et d'une année à l'autre a influencé le moment de la reproduction de quatre espèces d'ongulés montrant ces modèles contrastés dans la région de Masai Mara au Kenya. Les quatre espèces présentaient des pics de naissance au cours de la période optimale putative au début de la saison humide. Pour le hartebeest et l'impala, le pic de naissance est diffus et la progéniture naît tout au long de l'année. En revanche, le topi et le phacochère ont montré une concentration saisonnière étroite de naissances, avec des conceptions supprimées une fois que les précipitations mensuelles sont tombées en dessous d'un seuil. Les fortes précipitations de la saison précédente et les fortes pluies précoces de l'année en cours ont amélioré la survie au stade juvénile de toutes les espèces, à l'exception de l'impala. Nos résultats révèlent comment la variation des précipitations affectant la croissance des graminées et donc la nutrition des herbivores peut régir la phénologie reproductive des ongulés dans les latitudes tropicales où la variation de la longueur du jour est minime. Le mécanisme sous-jacent semble être la suppression des conceptions une fois que les gains nutritionnels deviennent insuffisants. En réagissant de manière proximale à la variation des précipitations au cours de l'année, les ongulés de la savane tropicale sont moins susceptibles d'être affectés négativement par les conséquences du réchauffement climatique sur la phénologie de la végétation que les ongulés du Nord montrant un contrôle photopériodique plus rigide sur le moment de la reproduction. En latitudes templadas altas, los ungulados generalmente dan a luz dentro de una ventana de tiempo estrecha cuando las condiciones son óptimas para la supervivencia de la descendencia en primavera o principios del verano, y utilizan conceptos cambiantes de fotoperíodo a tiempo para anticipar estas condiciones. Sin embargo, en latitudes tropicales bajas, la variación de la duración del día es mínima, y la variación de las precipitaciones hace que el ciclo estacional sea menos predecible. Sin embargo, varias especies de ungulados conservan picos de nacimiento estrechos en tales condiciones, mientras que otras muestran nacimientos muy extendidos a lo largo del año. Investigamos cómo la variación interanual de las precipitaciones influyó en el tiempo reproductivo de cuatro especies de ungulados que muestran estos patrones contrastantes en la región de Masai Mara en Kenia. Las cuatro especies exhibieron picos de nacimiento durante el periodo óptimo putativo en la estación húmeda temprana. Para hartebeest e impala, el pico de nacimiento era difuso y las crías nacían durante todo el año. Por el contrario, topi y jabalí mostraron una estrecha concentración estacional de nacimientos, con concepciones suprimidas una vez que las precipitaciones mensuales cayeron por debajo de un nivel umbral. Las altas precipitaciones en la temporada anterior y las altas lluvias tempranas en el año en curso mejoraron la supervivencia en la etapa juvenil para todas las especies, excepto los impalas. Nuestros hallazgos revelan cómo la variación de la precipitación que afecta el crecimiento de la hierba y, por lo tanto, la nutrición de los herbívoros, puede gobernar la fenología reproductiva de los ungulados en latitudes tropicales donde la variación de la duración del día es mínima. El mecanismo subyacente parece ser la supresión de las concepciones una vez que las ganancias nutricionales se vuelven insuficientes. Al responder proximalmente a la variación de las precipitaciones dentro del año, es menos probable que los ungulados de la sabana tropical se vean afectados negativamente por las consecuencias del calentamiento global para la fenología de la vegetación que los ungulados del norte que muestran un control fotoperiódico más rígido sobre el tiempo reproductivo. In high temperate latitudes, ungulates generally give birth within a narrow time window when conditions are optimal for offspring survival in spring or early summer, and use changing photoperiod to time conceptions so as to anticipate these conditions. However, in low tropical latitudes day length variation is minimal, and rainfall variation makes the seasonal cycle less predictable. Nevertheless, several ungulate species retain narrow birth peaks under such conditions, while others show births spread quite widely through the year. We investigated how within-year and between-year variation in rainfall influenced the reproductive timing of four ungulate species showing these contrasting patterns in the Masai Mara region of Kenya. All four species exhibited birth peaks during the putative optimal period in the early wet season. For hartebeest and impala, the birth peak was diffuse and offspring were born throughout the year. In contrast, topi and warthog showed a narrow seasonal concentration of births, with conceptions suppressed once monthly rainfall fell below a threshold level. High rainfall in the previous season and high early rains in the current year enhanced survival into the juvenile stage for all the species except impala. Our findings reveal how rainfall variation affecting grass growth and hence herbivore nutrition can govern the reproductive phenology of ungulates in tropical latitudes where day length variation is minimal. The underlying mechanism seems to be the suppression of conceptions once nutritional gains become insufficient. Through responding proximally to within-year variation in rainfall, tropical savanna ungulates are less likely to be affected adversely by the consequences of global warming for vegetation phenology than northern ungulates showing more rigid photoperiodic control over reproductive timing. في خطوط العرض المعتدلة العالية، تلد ذوات الحوافر عمومًا في غضون فترة زمنية ضيقة عندما تكون الظروف مثالية لبقاء النسل في الربيع أو أوائل الصيف، وتستخدم تغيير الفترة الضوئية إلى مفاهيم زمنية لتوقع هذه الظروف. ومع ذلك، في خطوط العرض الاستوائية المنخفضة، يكون تباين طول اليوم ضئيلًا، ويجعل تباين هطول الأمطار الدورة الموسمية أقل قابلية للتنبؤ. ومع ذلك، فإن العديد من الأنواع ذوات الحوافر تحتفظ بقمم ولادة ضيقة في ظل هذه الظروف، في حين أن البعض الآخر يظهر أن الولادات تنتشر على نطاق واسع خلال العام. لقد حققنا في كيفية تأثير التباين في هطول الأمطار خلال العام وبين الأعوام على التوقيت التكاثري لأربعة أنواع من ذوات الحوافر تظهر هذه الأنماط المتناقضة في منطقة ماساي مارا في كينيا. أظهرت جميع الأنواع الأربعة قمم ولادة خلال الفترة المثلى المفترضة في موسم الأمطار المبكر. بالنسبة لحيوان النحل والامبالا، كانت ذروة الولادة منتشرة وولدت ذرية على مدار العام. على النقيض من ذلك، أظهر التوبي والخنزير الحربي تركيزًا موسميًا ضيقًا للولادات، مع قمع المفاهيم بمجرد انخفاض هطول الأمطار الشهري إلى ما دون مستوى العتبة. عزز ارتفاع هطول الأمطار في الموسم السابق وارتفاع الأمطار المبكرة في العام الحالي البقاء على قيد الحياة في مرحلة الشباب لجميع الأنواع باستثناء الإمبالا. تكشف النتائج التي توصلنا إليها كيف أن تباين هطول الأمطار الذي يؤثر على نمو العشب وبالتالي تغذية الحيوانات العاشبة يمكن أن يحكم الفينولوجيا الإنجابية لذوات الحوافر في خطوط العرض الاستوائية حيث يكون تباين طول اليوم ضئيلًا. يبدو أن الآلية الأساسية هي قمع المفاهيم بمجرد أن تصبح المكاسب الغذائية غير كافية. من خلال الاستجابة القريبة من التباين في هطول الأمطار خلال العام، فإن ذوات الحوافر في السافانا الاستوائية أقل عرضة للتأثر سلبًا بعواقب الاحترار العالمي على فينولوجيا الغطاء النباتي من ذوات الحوافر الشمالية التي تظهر تحكمًا دوريًا ضوئيًا أكثر صرامة في توقيت التكاثر.

Dissertação de Mestrado em Design com a especialização em Design de Produto apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Mestre. O turismo vai muito além da atração de turistas para destinos paradisíacos, representando uma contribuição indispensável para o desenvolvimento de um país. O crescimento deste setor torna-o cada vez mais relevante para a economia, pela sua influência em inúmeros ramos que o rodeiam. No entanto, os recursos e a infraestrutura necessária para sustentar esse enorme crescimento do setor levou a um aumento da pressão sobre os recursos naturais, a biodiversidade e as comunidades locais. Num contexto marítimo-turístico (MT) a nível nacional, observa-se um cenário dominado pelo reaproveitamento de embarcações antigas ou originalmente destinadas a outra função sem a mínima adaptação e pela utilização da mesma embarcação para diferentes tipos de programas marítimos. Por outro lado no contexto internacional, os serviços marítimo-turísticos caracterizam-se por uma enorme dependência da sazonalidade, deparando-se com uma ampla variação do nível de procura, dificultada ainda pela variação das condições climáticas ente épocas. Em comum existe uma falta de investimento e inovação na construção ou reconstrução de embarcações com fontes de energias sustentáveis e adequadas ao tipo de atividade específico onde atuam. Os objetivos da investigação procuraram preencher esta lacuna, tanto a nível de adequação da embarcação aos requisitos de cada atividade, como da adaptação às condições impostas pela sazonalidade, considerando, simultaneamente, a inclusão de estratégias sustentáveis no setor. De forma a fazer o enquadramento do tema, analisaram-se os requisitos das atividades disponibilizadas e dos respetivos utilizadores, as necessidades e limitações da embarcação, as possibilidades para a integração da modularidade, bem como as vantagens e desvantagens das fontes de propulsão e materiais possíveis. Numa fase seguinte foram analisados e selecionados os dados mais relevantes para a posterior orientação do projeto, que constitui a etapa seguinte. Nesta investigação foi projetado um modelo que poderá representar, num futuro próximo, um contributo na construção de embarcações turísticas em sistemas modulares. De forma a alcançar tais objetivos, foi aplicada uma metodologia mista, fundamentada em três metodologias de base qualitativa não intervencionista e intervencionista. Esta inicia-se com a crítica da literatura, usada na fase seguinte para formalizar e testar uma hipótese através da investigação ativa, com entrevistas e casos de estudo. De seguida passa-se para a fase intervencionista de cariz projetual com a proposta de um modelo. Aplicando esta metodologia o objetivo será a consolidação da proposta para que o resultado da investigação seja um projeto inovador que responda aos requisitos atuais do mercado. O estudo de uma embarcação turística modular e sustentável pode representar um caminho para uma solução viável e promissora neste setor, sendo a falta de inovação e investimento, a pressão ambiental e a forte sazonalidade três problemáticas tão atuais e próximas da área de investigação. ABSTRACT: Tourism goes far beyond attracting tourists to paradisiacal destinations, representing an indispensable contribution to the development of a country. The growth of this sector makes it increasingly relevant to the economy, due to its influence in numerous branches that surround it. However, the resources and infrastructure needed to sustain this huge growth in the sector has led to increased pressure on natural resources, biodiversity and local communities. In a maritime-tourist context (MT) at national level, there is a scenario dominated by the reuse of old vessels or originally intended for another function without the slightest adaptation and by the use of the same vessel for different types of maritime programs. On the other hand, in the international context, maritime-touristic services are characterized by an enormous dependence on seasonality, facing a wide variation in the level of demand, further hampered by the variation of climatic conditions between seasons. In common, there is a lack of investment and innovation in the construction or reconstruction of vessels with sustainable energy sources and appropriate to the specific type of activity in which they operate. The research objectives sought to fill this gap, both in terms of adapting the vessel to the requirements of each activity, as well as adapting to the conditions imposed by seasonality, while considering the inclusion of sustainable strategies in the sector. In order to frame the theme, the requirements of the activities provided and the respective users were analyzed, the needs and limitations of the vessel, the possibilities for integrating modularity, as well as the advantages and disadvantages of the propulsion sources and possible materials . In a next phase, the most relevant data were analyzed and selected for the later orientation of the project, which constitutes the next stage. In this investigation, a model was designed that could represent, in the near future, a contribution in the construction of tourist boats in modular systems. In order to achieve these objectives, a mixed methodology was applied, based on three non-interventionist and interventional qualitative methodologies. This begins with the criticism of the literature, used in the next phase to formalize and test a hypothesis through active investigation, with interviews and case studies. Then we move on to the interventionist phase of a design nature with the proposal of a model. Applying this methodology the objective will be the consolidation of the proposal so that the result of the investigation is an innovative project that responds to the current requirements of the market. The study of a modular and sustainable tourist vessel can represent a path to a viable and promising solution in this sector, with the lack of innovation and investment, environmental pressure and strong seasonality being three issues so current and close to the research area. N/A

International audience Solar resource and forecasting in very short spatial and timescales (0–100 m, 0–30 min) is a challenging task that cannot be accurately achieved by satellite products or numerical weather predictions due to technical and methodological restrictions. For this reason, sky images from ground-based cameras are widely used during the last decade to deal with the high spatial and temporal variability of clouds and provide the needed inputs for numerical models for the current and forecasted (in short-term) solar irradiance. In this chapter, the available types of all-sky cameras/imagers are shortly presented. The chapter is focused on the state-of-the-art methodologies used to derive parameters needed for the estimations of solar resource and forecasting by a calibrated all-sky camera: cloud coverage, type, height, and velocity as well as aerosol optical properties. The application of these methodologies at Plataforma Solar de Almeria, in the frame of project: “Direct Normal Irradiance Nowcasting methods for optimized operation of concentrating solar technologies” (DNICast, http://www.dnicast-project.net/) is discussed. Finally, the chapter finishes with some propositions for future work in the recent, but quickly, developed research area.