16 research outputs found

    Symbionte - Desarrollo de un dispositivo IOT enfocado en la protección y monitorización de compresores en aplicaciones de aire acondicionado y refrigeración

    Get PDF
    ilustraciones, fotografías a colorThis project addresses the problem of the correct diagnosis of air conditioning and refrigeration systems compressors, using instrumentation easily found in the market. For this work, the use of an Espressif ESP32 controller programmed under the Arduino language is proposed, in addition to sensors and algorithms based on trends that allow real-time knowledge of relevant variables of the process that allows anticipating to the failures under a scheme condition-based maintenance.Este proyecto aborda el problema del diagnóstico correcto de compresores de sistemas de aire acondicionado y refrigeración, utilizando instrumentación fácil de encontrar en el mercado. Para este trabajo se propone el uso de un controlador Espressif ESP32 programado bajo el lenguaje Arduino, además de sensores y algoritmos basados en tendencias que permitan conocer en tiempo real de variables relevantes del proceso que permitan anticiparse a los fallos bajo un esquema de mantenimiento basado en condiciones. (Texto tomado de la fuente)MaestríaMagíster en Ingeniería - Automatización IndustrialProcess and Machines Automation, Instrumentation, Tecnology for Educatio

    The Long-term Role of Hydropower in Ecuador’s Power System: Assessing Climate Change and Cost Uncertainties

    Get PDF
    Hydropower is the leading source of renewable electricity generation worldwide. Traditionally, hydropower has been perceived as a cheap, reliable and a low greenhouse gas emitting energy source. However, evidence suggests that, given hydropower’s dependency on the hydrological cycle, it could be particularly vulnerable to the effects of climate change. In addition, hydropower infrastructure has shown to be prone to significant cost overruns and delays, due to the inherent complexities that accompany its deployment. Previous research has quantified these issues but little investigation has taken place to assess them in an integrated manner. The interest of this research is to assess how assumptions about climate change, policy and costs can induce shifts in generation portfolio optima, particularly of power systems that are based or plan to be based on hydropower in the long-term. For this purpose, a series of hydrological, hydropower and energy system models have been developed in order to take these factors into account, and search generation alternatives regarding technical characteristics (i.e. power system operation, energy system configuration, demand), economic specificities (i.e. technology costs, resource prices, cost risk) and geospatial factors (i.e. water resource distribution, precipitation, climate change). The proposed method is illustrated with a case study for the Republic of Ecuador until 2050, a South American country that relies heavily on hydropower and plans to continue harnessing its potential in the future. Findings have identified that hydropower will remain an important least-cost and low emitting electricity source in Ecuador’s future, however its share in the electricity generation matrix could vary greatly. Furthermore, portfolio analysis has revealed the trade-off between generation portfolio cost and risk. Suggesting that shifting away from run-ofriver hydropower, gas and oil-fired generation towards a system with larger shares of hydropower with reservoir, solar PV and geothermal energy can help hedge the power system against the uncertainties of climate change, fossil fuel price volatility and electricity infrastructure cost overruns. Failing to diversify the power system could create a lock-in to natural gas. This research adds to the literature seeking to provide insights for new hydropower developments particularly concentrated in emerging economies of South East Asia, South America and Africa

    Impacts of climate variability and climate change on renewable power generation

    Get PDF
    Anthropogenic climate change represents a major risk for human civilization and its mitigation requires reductions of greenhouse gas emissions. To stay consistent with the long-term temperature targets of international climate policy, global greenhouse gas emissions have to reach zero within a few decades. Such a dramatic transition towards sustainability in all sectors of human activity requires the decarbonization of power generation at an early stage. In absence of other viable technology choices and given the significant cost declines, renewable power generation forms the backbone of the decarbonization. In contrast to thermal power plants, most renewables are not dispatchable but their generation dynamics are governed by the weather. This dissertation adds to the quantification of impacts of climate variability on wind power generation on different time scales. In particular, it shows that inter-annual wind power generation variability already today has a strong influence on congestion management costs in Germany. Understanding this variability as a normal system feature helps to prevent short-sighted reactions in legislation and power system design. Moreover, it is shown that relevant multi-decadal wind power generation variability exists. Owing to timescales of up to 50 years, these modes are not sufficiently sampled in any modern reanalysis (e.g., MERRA2 or ERA-Interim), which currently cover around 40 years. Consequently, power system assessments based on modern reanalyses may be flawed and should be complemented by multi-decadal assessments. In this context, I also show that 20th century reanalyses (ERA-20C, CERA20C, 20CRv2c) disagree strongly and systematically with respect to long-term wind speed trends. The discrepancy can be traced back to marine wind speed observations which also feature strong upward wind trends that are likely due to an evolving measurement technique. As a consequence, 20th century reanalyses should be employed with care and cross-validation of results is recommended. Due to their weather dependency, renewables are potentially vulnerable to climate change. Indeed, I show that the benefits of large-scale transmission infrastructure in Europe shrink under strong climate change (RCP8.5). The effect is robust across a five member EUROCORDEX ensemble and can be solidified in a larger CMIP5 ensemble. It is rooted in more homogeneous wind conditions over Europe that lead to less smoothing effects via large scale spatial integration. Lastly, the debate around negative emission technologies to enlarge the carbon budget currently focuses on land-based approaches such as Bioenergy with Carbon Capture and Storage. Based on a schematic integration of Direct Air Capture (DAC), we show that its flexibility complements renewable generation variability and can help to integrate large shares of renewables

    Annual report of the board of selectmen and school board of the town of Pembroke together with the reports of the treasurer, trustees, officers and boards, committees and commissions of the town for the year ending December 31, 2009.

    Get PDF
    This is an annual report containing vital statistics for a town/city in the state of New Hampshire

    Computational Modelling of Concrete and Concrete Structures

    Get PDF
    Computational Modelling of Concrete and Concrete Structures contains the contributions to the EURO-C 2022 conference (Vienna, Austria, 23-26 May 2022). The papers review and discuss research advancements and assess the applicability and robustness of methods and models for the analysis and design of concrete, fibre-reinforced and prestressed concrete structures, as well as masonry structures. Recent developments include methods of machine learning, novel discretisation methods, probabilistic models, and consideration of a growing number of micro-structural aspects in multi-scale and multi-physics settings. In addition, trends towards the material scale with new fibres and 3D printable concretes, and life-cycle oriented models for ageing and durability of existing and new concrete infrastructure are clearly visible. Overall computational robustness of numerical predictions and mathematical rigour have further increased, accompanied by careful model validation based on respective experimental programmes. The book will serve as an important reference for both academics and professionals, stimulating new research directions in the field of computational modelling of concrete and its application to the analysis of concrete structures. EURO-C 2022 is the eighth edition of the EURO-C conference series after Innsbruck 1994, Bad Gastein 1998, St. Johann im Pongau 2003, Mayrhofen 2006, Schladming 2010, St. Anton am Arlberg 2014, and Bad Hofgastein 2018. The overarching focus of the conferences is on computational methods and numerical models for the analysis of concrete and concrete structures

    Limitations to human livelihoods and well-being in the context of climate change

    Get PDF
    Diese Arbeit entwickelt zunächst einen Ansatz, der die Quantifizierung der Angemessenheit von Lebensbedingungen für Wohlbefinden und Entwicklung (Adequate Human livelihood conditions for wEll-being And Development (AHEAD)) auf globaler Ebene ermöglicht. Der Ansatz erlaubt es, sektorale Klimaauswirkungen direkt in Beziehung zu den Voraussetzungen für adäquate Lebensbedingungen zu setzen. Weiterhin befasst sich die Arbeit im Detail mit den Themen Wasserverfügbarkeit und menschlicher Gesundheit und zeigt auf, wie regionale und lokale Untersuchungen die Aussagekraft von allgemeinen, globalen Studien erweitern können. Die Ergebnisse des zeigen, dass Wasser als Element von AHEAD eine besonders aktive Komponente des Systems ist, so dass durch Klimawandel bedingte Veränderungen starke Auswirkungen auf das Gesamtsystem zur Folge haben können. Die Quantifizierung von AHEAD zeigt außerdem, dass Wasserknappheit die Lebensbedingungen bereits heute in vielen Regionen limitiert und Auswirkungen des Klimawandels diese Limitierungen weiter verstärken. Die detaillierte Analyse zum Thema Wasser ermöglicht die Ableitung von geeigneten Ansatzpunkten zur Verbesserung der Bedingungen. In einem ähnlichen Ansatz werden die vielfältigen sozio-ökonomischen und natürlichen Einflussfaktoren, die die Auswirkungen von Hitzestress auf die menschliche Gesundheit beeinflussen integriert, so dass die Ableitung relevanter Informationen zur Reduktion von Klimaauswirkungen auf das menschliche Wohlbefinden möglich wird. Eine Verbindung der vorgestellten Ansätze erlaubt es, Aussagen über die Art, die Intensität sowie die räumliche Ausprägung von aktuellen und zukünftigen Einschränkungen von Lebensbedingungen zu treffen.This thesis develops an approach to assess Adequate Human livelihood conditions for wEll-being And Development (AHEAD) on a global scale. The approach allows to relate sectoral impacts of climate change to an integrated measure of livelihood limitations, taking into account important determinants of the society as well as the environment. Additionally, detailed sectoral studies on water availability and human health show how local and regional studies of specific livelihood aspects can complement generic, global assessments and provide an overall indication of the nature, severity and spatial distribution of limitations to human livelihoods. The results show, that water as an element of AHEAD is one of the most active system components. Impacts of climate change on water may have strong indirect effects on livelihood adequacy. The potential impacts of changes in water availability on AHEAD are quantified, showing that water scarcity limits livelihood adequacy in many regions of the world. The utilisation of an ensemble of climate change and water models further allows to assess the relevance of model related uncertainty in this regard. As water availability plays a crucial role for the fulfilment of livelihood needs, the global assessment is complemented by a detailed analysis of the adequacy of water availability for relevant sectors. By taking into account sector-specific determinants, the approach allows to depict limitations in detail, also giving indications as to how water adequacy may be improved. Similarly, the analysis of heatwave impacts on human health provides a methodology to assess the multiple environmental and human influences which affect vulnerability and provides specific information on potential adaptation measures to reduce climate impacts. By identifying the most decisive limiting factors, applicable information on how to most effectively improve human livelihoods is generated

    Computational Modelling of Concrete and Concrete Structures

    Get PDF
    Computational Modelling of Concrete and Concrete Structures contains the contributions to the EURO-C 2022 conference (Vienna, Austria, 23-26 May 2022). The papers review and discuss research advancements and assess the applicability and robustness of methods and models for the analysis and design of concrete, fibre-reinforced and prestressed concrete structures, as well as masonry structures. Recent developments include methods of machine learning, novel discretisation methods, probabilistic models, and consideration of a growing number of micro-structural aspects in multi-scale and multi-physics settings. In addition, trends towards the material scale with new fibres and 3D printable concretes, and life-cycle oriented models for ageing and durability of existing and new concrete infrastructure are clearly visible. Overall computational robustness of numerical predictions and mathematical rigour have further increased, accompanied by careful model validation based on respective experimental programmes. The book will serve as an important reference for both academics and professionals, stimulating new research directions in the field of computational modelling of concrete and its application to the analysis of concrete structures. EURO-C 2022 is the eighth edition of the EURO-C conference series after Innsbruck 1994, Bad Gastein 1998, St. Johann im Pongau 2003, Mayrhofen 2006, Schladming 2010, St. Anton am Arlberg 2014, and Bad Hofgastein 2018. The overarching focus of the conferences is on computational methods and numerical models for the analysis of concrete and concrete structures

    Application of heat pumps and thermal storage systems for improved control and performance of microgrids

    Get PDF
    The high penetration of renewable energy sources (RES), in particular, the rooftop photovoltaic (PV) systems in power systems, causes rapid ramps in power generation to supply load during peak-load periods. Residential and commercial buildings have considerable potential for providing load exibility by exploiting energy-e_cient devices like ground source heat pump (GSHP). The proper integration of PV systems with the GSHP could reduce power demand from demand-side. This research provides a practical attempt to integrate PV systems and GSHPs e_ectively into buildings and the grid. The multi-directional approach in this work requires an optimal control strategy to reduce energy cost and provide an opportunity for power trade-o_ or feed-in in the electricity market. In this study, some optimal control models are developed to overcome both the operational and technical constraints of demand-side management (DSM) and for optimum integration of RES. This research focuses on the development of an optimal real-time thermal energy management system for smart homes to respond to DR for peak-load shifting. The intention is to manage the operation of a GSHP to produce the desired amount of thermal energy by controlling the volume and temperature of the stored water in the thermal energy storage (TES) while optimising the operation of the heat distributors to control indoor temperature. This thesis proposes a new framework for optimal sizing design and real-time operation of energy storage systems in a residential building equipped with a PV system, heat pump (HP), and thermal and electrical energy storage systems. The results of this research demonstrate to rooftop PV system owners that investment in combined TSS and battery can be more profitable as this system can minimise life cycle costs. This thesis also presents an analysis of the potential impact of residential HP systems into reserve capacity market. This research presents a business aggregate model for controlling residential HPs (RHPs) of a group of houses that energy aggregators can utilise to earn capacity credits. A control strategy is proposed based on a dynamic aggregate RHPs coupled with TES model and predicting trading intervals capacity requirements through forecasting demand and non-scheduled generation. RHPs coupled with TES are optimised to provide DSM reserve capacity. A rebound effect reduction method is proposed that reduces the peak rebound RHPs power

    Parametric reduced-order aeroelastic modelling for analysis, dynamic system interpolation and control of flexible aircraft

    Get PDF
    This work presents an integral framework to derive aeroelastic models for very flexible aircraft that can be used in design routines, operational envelope analysis and control applications. Aircraft are modelled using a nonlinear geometrically-exact beam model coupled with an Unsteady Vortex-Lattice Method aerodynamic solver, capable of capturing important nonlinear couplings and effects that significantly impact the flight characteristics of very flexible aircraft. Then, complete linearised expressions of the aircraft system about trim reference conditions at possibly large deformations are presented. The nature of the aerodynamic models results in a high-dimensional system that requires of model reduction methods for efficient analysis and manipulation. Krylov-subspace model reduction methods are implemented to reduce the dimensionality of the multi-input multi-output linearised aerodynamic model and achieve a very significant reduction in the size of the size of the system. The reduced aerodynamic model is then coupled with a modal expression of the linearised beam model, resulting in a compact aeroelastic state-space that can be efficiently used on desktop hardware for linear analysis or as part of internal control models. These have been used to explore the design space of a very flexible wing with complex aeroelastic properties to determine the flutter boundaries, for which experimental data has become available that validates the methods presented herein. Additionally, they have been integrated in a model predictive control framework, where the reduced linear aerodynamic model is part of the control model, and the simulation plant is the nonlinear flight dynamic/aeroelastic model connected as a hardware-in-the-loop platform. Finally, in order to accelerate the design space exploration of very flexible structures, state-space interpolation methods are sought to obtain, with a few linearised models sampled across the domain, interpolated state-spaces anywhere in the parameter-space in a fast and accurate manner. The performance of the interpolation schemes is heavily dependent on the location of the sampling points on the design space, therefore, a novel adaptive Bayesian sampling scheme is presented to choose these points in an optimal approach that minimises the interpolation error function.Open Acces
    corecore