INCORPORATING REAL SCIENCE INTO THE SECONDARY CLASSROOM: AEROSOLS AND CLIMATE CHANGE

Climate science and climate change are included in the Next Generation Science Standards, curriculum standards that were released in 2013. How to incorporate these topics, especially climate change, has been a difficult task for teachers. A team of scientists are studying aerosols in the free troposphere; what their properties are, how they change while in the atmosphere and where they came from. Lessons were created based on this real, ongoing scientific research being conducted in the Azores. During these activities, students are exposed to what scientists actually do in the form of videos and participate in similar tasks such as conducting experiments, collecting data, and analyzing data. At the conclusion of the lessons, students will form conclusions based on the evidence they have at the time.

Lightweight Middleware for Software Defined Radio (SDR) Inter-Components Communication

The ability to use Software Defined Radio (SDR) in the civilian mobile applications will make it possible for the next generation of mobile devices to handle multi-standard personal wireless devices and ubiquitous wireless devices. The original military standard created many beneficial characteristics for SDR, but resulted in a number of disadvantages as well. Many challenges in commercializing SDR are still the subject of interest in the software radio research community. Four main issues that have been already addressed are performance, size, weight, and power. This investigation presents an in-depth study of SDR inter-components communications in terms of total link delay related to the number of components and packet sizes in systems based on Software Communication Architecture (SCA). The study is based on the investigation of the controlled environment platform. Results suggest that the total link delay does not linearly increase with the number of components and the packet sizes. The closed form expression of the delay was modeled using a logistic function in terms of the number of components and packet sizes. The model performed well when the number of components was large. Based upon the mobility applications, energy consumption has become one of the most crucial limitations. SDR will not only provide flexibility of multi-protocol support, but this desirable feature will also bring a choice of mobile protocols. Having such a variety of choices available creates a problem in the selection of the most appropriate protocol to transmit. An investigation in a real-time algorithm to optimize energy efficiency was also performed. Communication energy models were used including switching estimation to develop a waveform selection algorithm. Simulations were performed to validate the concept.

Tubular and Sector Heat Pipes with Interconnected Branches for Gas Turbine and/or Compressor Cooling

Designing turbines for either aerospace or power production is a daunting task for any heat transfer scientist or engineer. Turbine designers are continuously pursuing better ways to convert the stored chemical energy in the fuel into useful work with maximum efficiency. Based on thermodynamic principles, one way to improve thermal efficiency is to increase the turbine inlet pressure and temperature. Generally, the inlet temperature may exceed the capabilities of standard materials for safe and long-life operation of the turbine. Next generation propulsion systems, whether for new supersonic transport or for improving existing aviation transport, will require more aggressive cooling system for many hot-gas-path components of the turbine. Heat pipe technology offers a possible cooling technique for the structures exposed to the high heat fluxes. Hence, the objective of this dissertation is to develop new radially rotating heat pipe systems that integrate multiple rotating miniature heat pipes with a common reservoir for a more effective and practical solution to turbine or compressor cooling. In this dissertation, two radially rotating miniature heat pipes and two sector heat pipes are analyzed and studied by utilizing suitable fluid flow and heat transfer modeling along with experimental tests. Analytical solutions for the film thickness and the lengthwise vapor temperature distribution for a single heat pipe are derived. Experimental tests on single radially rotating miniature heat pipes and sector heat pipes are undertaken with different important parameters and the manner in which these parameters affect heat pipe operation. Analytical and experimental studies have proven that the radially rotating miniature heat pipes have an incredibly high effective thermal conductance and an enormous heat transfer capability. Concurrently, the heat pipe has an uncomplicated structure and relatively low manufacturing costs. The heat pipe can also resist strong vibrations and is well suited for a high temperature environment. Hence, the heat pipes with a common reservoir make incorporation of heat pipes into turbo-machinery much more feasible and cost effective.

Acumen : an open-source testbed for cyber-physical systems research

Developing Cyber-Physical Systems requires methods and tools to support simulation and verification of hybrid (both continuous and discrete) models. The Acumen modeling and simulation language is an open source testbed for exploring the design space of what rigorousbut- practical next-generation tools can deliver to developers of Cyber- Physical Systems. Like verification tools, a design goal for Acumen is to provide rigorous results. Like simulation tools, it aims to be intuitive, practical, and scalable. However, it is far from evident whether these two goals can be achieved simultaneously. This paper explains the primary design goals for Acumen, the core challenges that must be addressed in order to achieve these goals, the “agile research method” taken by the project, the steps taken to realize these goals, the key lessons learned, and the emerging language design.

Adaptive edge analytics for distributed networked control of water systems

Over the last decade, there has been a trend where water utility companies aim to make water distribution networks more intelligent in order to improve their quality of service, reduce water waste, minimize maintenance costs etc., by incorporating IoT technologies. Current state of the art solutions use expensive power hungry deployments to monitor and transmit water network states periodically in order to detect anomalous behaviors such as water leakage and bursts. However, more than 97% of water network assets are remote away from power and are often in geographically remote underpopulated areas, facts that make current approaches unsuitable for next generation more dynamic adaptive water networks. Battery-driven wireless sensor/actuator based solutions are theoretically the perfect choice to support next generation water distribution. In this paper, we present an end-to-end water leak localization system, which exploits edge processing and enables the use of battery-driven sensor nodes. Our system combines a lightweight edge anomaly detection algorithm based on compression rates and an efficient localization algorithm based on graph theory. The edge anomaly detection and localization elements of the systems produce a timely and accurate localization result and reduce the communication by 99% compared to the traditional periodic communication. We evaluated our schemes by deploying non-intrusive sensors measuring vibrational data on a real-world water test rig that have had controlled leakage and burst scenarios implemented.

Modifying the band gap and optical properties of Germanium nanowires by surface termination

Semiconductor nanowires, based on silicon (Si) or germanium (Ge) are leading candidates for many ICT applications, including next generation transistors, optoelectronics, gas and biosensing and photovoltaics. Key to these applications is the possibility to tune the band gap by changing the diameter of the nanowire. Ge nanowires of different diameter have been studied with H termination, but, using ideas from chemistry, changing the surface terminating group can be used to modulate the band gap. In this paper we apply the generalised gradient approximation of density functional theory (GGA-DFT) and hybrid DFT to study the effect of diameter and surface termination using –H, –NH2 and –OH groups on the band gap of (001), (110) and (111) oriented germanium nanowires. We show that the surface terminating group allows both the magnitude and the nature of the band gap to be changed. We further show that the absorption edge shifts to longer wavelength with the –NH2 and –OH terminations compared to the –H termination and we trace the origin of this effect to valence band modifications upon modifying the nanowire with –NH2 or –OH. These results show that it is possible to tune the band gap of small diameter Ge nanowires over a range of ca. 1.1 eV by simple surface chemistry.

Productividad sectorial y cambio estructural en América Latina

En este documento se analiza el proceso de transformación estructural para algunas economías de América Latina y su comparación con los milagros asiáticos. De igual forma, para el caso de Colombia y de Corea del Sur, se describe el comportamiento de la productividad agregada y su descomposición sectorial. Los resultados evidencian que, en los dos países, el sector de servicios ha ganado participación en las últimas décadas. Para el caso de Colombia este sector explica en gran medida la baja competitividad del país frente a los Estados Unidos. Por su parte, en Corea del Sur la brecha de productividad con los Estados Unidos se ha cerrado en los tres sectores (agricultura, industria y servicios). Finalmente, se adapta un modelo de cambio estructural para estas dos economías y se encuentra que para Colombia el modelo logra reproducir las tendencias observadas en los datos. Para Corea el modelo no ajusta durante la época de industrialización tardía, pero para las últimas décadas replica de manera cercana los datos.

Liderazgo y cultura organizacional en Latinoamerica

El presente estudio de corte descriptivo hace una revisión teórica de 68 artículos de 11 países de Latinoamérica con el fin de dar a conocer el panorama organizacional con relación a la cultura organizacional y el liderazgo en la región y cómo este ha ido evolucionando en el tiempo. La metodología utilizada se enfocó en un conteo de frecuencias usando el modelo de liderazgo y cultura organizacional de Bass y Avolio (Bass, 1999) permitiendo ordenar en tres estilos de liderazgo la información encontrada en la revisión teórica, y a su vez cada uno de los liderazgos con sus creencias, éstas tomadas como variables de la cultura organizacional. Finalmente se encontraron diferentes tipos de tendencias a nivel de los tipos de liderazgo implementados en las organizaciones y la cultura organizacional que se adopta. Se plantea la necesidad de profundizar más y de forma empírica en la temática planteada para que se conozcan las transformaciones que se han dado en el contexto organizacional y el impacto sea mayor en un futuro cercano.

Diagnostico estratégico del suministro de hemocomponentes en Colombia y posibles alternativas de mejora

Objetivo: realizar un diagnóstico respecto a la oferta demanda de hemocomponentes, en el contexto epidemiológico colombiano para que sirva de base en la formulación de futuros modelos logísticos de cadena de suministro que permita responder eficientemente a las necesidades transfusionales del país Método: se realizó un estudio descriptivo retrospectivo basado en las fuentes oficiales de información colombiana respecto a condiciones epidemiológicas poblacionales y su relación respecto a captación y transfusión de sangre, así como las posibilidades de conexiones aéreas. Resultados: actualmente 62.3% de la captación es aportada principalmente por 19% de los bancos de sangre del país (16 / 82), ubicados en 8 ciudades del país las cuales evidencian mejores condiciones de salud e índices de densidad poblacional superiores al promedio nacional. Adicionalmente, desde estas ciudades se puede hacer cubrimiento de hemocomponentes en todo el territorio nacional dadas las condiciones de las conexiones aéreas. Conclusiones: es posible con base en el diagnostico presentado, plantear opciones que apunten a mejorar la eficiencia en la cadena de suministros de hemocomponentes, centralizando la captación de sangre en las áreas donde se cuenta con mejores condiciones de salud y mayores densidades poblacionales. Lo anterior permitiría minimizar los porcentajes de incineración de unidades de glóbulos rojos por vencimiento al mejorar las redes de distribución y de esta manera reducir costos de operación. Debe además fortalecerse la gestión de inventarios desde los servicios de transfusión para lograr minimizar las perdidas. Lo anterior requiere control gubernamental dado que al considerarse la sangre como un bien de interés público, su uso no puede ser indiscriminado.

Development and optimization of fibre-shaped dye-sensitized solar cells employing an innovative fully organic sensitizer

The quality of human life depends to a large degree on the availability of energy. In recent years, photovoltaic technology has been growing extraordinarily as a suitable source of energy, as a consequence of the increasing concern over the impact of fossil fuels on climate change. Developing affordable and highly efficiently photovoltaic technologies is the ultimate goal in this direction. Dye-sensitized solar cells (DSSCs) offer an efficient and easily implementing technology for future energy supply. Compared to conventional silicon solar cells, they provide comparable power conversion efficiency at low material and manufacturing costs. In addition, DSSCs are able to harvest low-intensity light in diffuse illumination conditions and then represent one of the most promising alternatives to the traditional photovoltaic technology, even more when trying to move towards flexible and transparent portable devices. Among these, considering the increasing demand of modern electronics for small, portable and wearable integrated optoelectronic devices, Fibre Dye-Sensitized Solar Cells (FDSSCs) have gained increasing interest as suitable energy provision systems for the development of the next-generation of smart products, namely “electronic textiles” or “e-textiles”. In this thesis, several key parameters towards the optimization of FDSSCs based on inexpensive and abundant TiO2 as photoanode and a new innovative fully organic sensitizer were studied. In particular, the effect of various FDSSCs components on the device properties pertaining to the cell architecture in terms of photoanode oxide layer thickness, electrolytic system, cell length and electrodes substrates were examined. The photovoltaic performances of the as obtained FDSSCs were fully characterized. Finally, the metal part of the devices (wire substrate) was substituted with substrates suitable for the textile industry as a fundamental step towards commercial exploitation.

Open Education and OER - A guide and call to action for policy makers

Executive Summary ALT has produced this call to action to highlight to education policy makers and professionals how Open Education and OER can expand inclusive and equitable access to education and lifelong learning, widen participation, and create new opportunities for the next generation of teachers and learners, preparing them to become fully engaged digital citizens. Open Education can also promote knowledge transfer while enhancing quality and sustainability, supporting social inclusion and creating a culture of inter-institutional collaboration and sharing. One of ALT’s three strategic aims is to increase the impact of Learning Technology for the wider community and we are issuing this call to action for policy makers to mandate that publicly funded educational resources are released under open licence to ensure that they reside in the public domain and are freely and openly available to all. This will be of wide benefit, but in particular will enable education providers and learning technology professionals to: Keep up to date with the rapid pace of technological innovation Develop critical, informed approaches to the implementation of Learning Technology and the impact on learners Scale up knowledge sharing and its benefits across sectors.

Non-standard signatures from Cosmic Microwave Background polarisation

In this Thesis we focus on non-standard signatures from CMB polarisation, which might hint at the existence of new phenomena beyond the standard models for Cosmology and Particle physics. With the Planck ESA mission, CMB temperature anisotropies have been observed at the cosmic variance limit, but polarisation remains to be further investigated. CMB polarisation data are important not only because they contribute to provide tighter constraints of cosmological parameters but also because they allow the investigation of physical processes that would be precluded if just the CMB temperature maps were considered. We take polarisation data into account to assess the statistical significance of the anomalies currently observed only in the CMB temperature map and to constrain the Cosmic Birefringence (CB) effect, which is expected in parity-violating extensions of the standard electromagnetism. In particular, we propose a new one-dimensional estimator for the lack of power anomaly capable of taking both temperature and polarisation into account jointly. With the aim of studying the anisotropic CB we develop and perform two different and complementary methods able to evaluate the power spectrum of the CB. Finally, by employing these estimators and methodologies on Planck data we provide new constraints beyond what already known in literature. The measure of CMB polarisation represents a technological challenge and to make accurate estimates, one has to keep an exquisite control of the systematic effects. In order to investigate the impact of spurious signal in forthcoming CMB polarisation experiments, we study the interplay between half-wave plates (HWP) non-idealities and the beams. Our analysis suggests that certain HWP configurations, depending on the complexity of Galactic foregrounds and the beam models, significantly impacts the B-mode reconstruction fidelity and could limit the capabilities of next-generation CMB experiments. We provide also a first study of the impact of non-ideal HWPs on CB.

Enabling 5G and beyond: millimeter wave propagation and cloud RAN evolution

In the last few years, mobile wireless technology has gone through a revolutionary change. Web-enabled devices have evolved into essential tools for communication, information, and entertainment. The fifth generation (5G) of mobile communication networks is envisioned to be a key enabler of the next upcoming wireless revolution. Millimeter wave (mmWave) spectrum and the evolution of Cloud Radio Access Networks (C-RANs) are two of the main technological innovations of 5G wireless systems and beyond. Because of the current spectrum-shortage condition, mmWaves have been proposed for the next generation systems, providing larger bandwidths and higher data rates. Consequently, new radio channel models are being developed. Recently, deterministic ray-based models such as Ray-Tracing (RT) are getting more attractive thanks to their frequency-agility and reliable predictions. A modern RT software has been calibrated and used to analyze the mmWave channel. Knowledge of the electromagnetic properties of materials is therefore essential. Hence, an item-level electromagnetic characterization of common construction materials has been successfully achieved to obtain information about their complex relative permittivity. A complete tuning of the RT tool has been performed against indoor and outdoor measurement campaigns at 27 and 38 GHz, setting the basis for the future development of advanced beamforming techniques which rely on deterministic propagation models (as RT). C-RAN is a novel mobile network architecture which can address a number of challenges that network operators are facing in order to meet the continuous customers’ demands. C-RANs have already been adopted in advanced 4G deployments; however, there are still some issues to deal with, especially considering the bandwidth requirements set by the forthcoming 5G systems. Open RAN specifications have been proposed to overcome the new 5G challenges set on C-RAN architectures, including synchronization aspects. In this work it is described an FPGA implementation of the Synchronization Plane for an O-RAN-compliant radio system.

Le ricadute dei vincoli di bilancio europei sugli Enti territoriali. Nuove norme per la stabilità.

La disciplina del pareggio di bilancio è in continua evoluzione, soprattutto a fronte delle nuove esigenze finanziarie per contrastare la pandemia. Questo elaborato, studiando la governance economica strutturata dopo la crisi dei debiti, le derivanti scelte italiane in materia di costituzionalizzazione del pareggio di bilancio e le conseguenze sulle autonomie locali, dimostra come il sistema di gestione delle finanze pubbliche a livello comunitario si stia completando, generando un rapporto normativo ciclico tra il livello europeo e quello locale. Ne è emersa una conflittualità tra le Regioni e lo Stato, che è analizzata al fine di comprendere la giustiziabilità costituzionale del pareggio di bilancio, osservando le esigenze di bilanciamento tra l’equilibrio finanziario e la tutela dei diritti sociali. La Corte Costituzionale ha recentemente conferito, in via giurisprudenziale, alla Corte dei Conti la potestà di svolgere un controllo diretto di costituzionalità del rispetto dell’equilibrio di bilancio degli enti nazionali e territoriali. Particolare attenzione viene data, poi, a seguito degli effetti della pandemia da Covid-19 sui bilanci degli Stati. A fronte della crisi pandemica, per la prima volta dall’approvazione del TSCG, la Commissione ha attivato la clausola di salvaguardia generale per sospendere il Patto di Stabilità (c.d. escape clause). Questa clausola ha permesso ai Paesi di ricorrere agli scostamenti di bilancio. Viene infine analizzato il piano “Next Generation EU”, che centralizza i prestiti verso gli Stati membri nel bilancio dell’Unione ed attinge dal mercato dei capitali le risorse necessarie per finanziare un totale di 750 miliardi, attraverso l’emissione di obbligazioni “Eu Bills”. Per la prima volta nella storia, l’Unione, nelle parole della Commissione, agisce sui mercati come se fosse uno Stato. La portata straordinaria del NGEU, con l’emissione di titoli europei, porta ad una sostanziale mutualizzazione dei debiti ed appare come un passo fondamentale verso il completamento dell’UEM e di un sistema federale.

Development and characterization of innovative graphene-based composites

Over the last decade, graphene and related materials (GRM) have drawn significant interest and resources for their development into the next generation of composite materials. This is because these nanoparticles have the ability to operate as reinforcing additives capable of imparting considerable mechanical property increases while also embedding multi-functional advantages on the host matrix. Because graphene and 2D materials are still in their early stages, the relative maturity of different types of composite systems varies. As a result, certain nanocomposite systems are currently commercially accessible, while others are not yet sufficiently developed to enter the market. A substantial emphasis has been placed on developing thermoplastic and thermosetting materials that combine a variety of mechanical and functional qualities. These include higher strength and stiffness, increased thermal and electrical conductivity, improved barrier properties, fire retardancy, and others, with the ultimate goal of providing multifunctionality to already employed composites. The work presented in this thesis investigates the use and benefits that GRM could bring to composites for a variety of applications, with the goal of realizing multifunctional components with improved properties that leads to lightweight and, as a result, energy and cost savings and pollution reduction in the environment. In particular, we worked on the following topics: • Benchmarking of commercial GRM-based master batches; • GRM-coatings for water uptake reduction; • GRM as thermo-electrical anti-icing /de-icing system; • GRM for Out of Oven curing of composites.