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Imagen de apoyo de  A Dos Music Project A Report of the First National Music Education Tour in Colombia

A Dos Music Project A Report of the First National Music Education Tour in Colombia

Por: Luz Elena Sarmiento Lozada | Fecha: 2018

Abstract: The A Dos Music Project is a Latin American music clarinet duet founded by professional clarinetists Ivan Valbuena and Luz Sarmiento, a Colombian couple who have been expanding the horizons of Latin music by performing traditional music with a nonconventional instrumentation and demanding arrangements. By combining the technical and artistic possibilities of the clarinet with the fresh and unique sound of Latin rhythms, A Dos Music Project displays a virtuosic, improvisatory, and innovative manner of performance that reaches all kinds of audiences. The ensemble’s mission is educational development and the promotion of music and art as a means of social transformation. This clarinet duet strives to engage new generations of audiences through interactive concerts and workshops designed to inspire young musicians in disadvantaged areas of the world, including refugee camps in Sweden and Germany and El Sistema1 -inspired programs in the US and Latin America. This initiative was inspired by the important role of the clarinet in Colombian folk music and the deep influence that this music had on the artistic development of the musicians of the ensemble. The virtuosic features and flexibility of the clarinet allow the players to perform Colombian and Latin American music with a reduced instrumentation of just two clarinets. The complexity of the rhythms and colors of the Latin Music are explored in advanced and demanding arrangements and compositions, featuring the technical and musical capabilities of the instrument. As teaching artists, the members of A Dos Music Project (ADMP) look to integrate their art and skills into a wide range of settings while engaging their audiences in learning experiences. This purpose led them to develop a workshop designed to provide young musicians with the opportunity to interact with a piece of music by using their body. By creating muscular sensations and allowing an interior perception of the sound, rhythm, and form, young musicians can improve their hearing and consequently their playing. The use of body percussion plays an important role in the development of the ADMP workshop since it makes a direct connection between the particular characteristics of Latin music and the learning experience. The A Dos Music Project National Tour was an innovative and ambitious community outreach music initiative undertaken by the clarinet duet A Dos Music Project during the month of July 2017. The tour sought to achieve the following objectives: - To introduce isolated communities to the benefits of the artistic education and music making as a transformative experience through the performances and life testimony of the members of A Dos Music Project. - To provide under-served music programs with musical knowledge and performances skills at a high level. - To improve self-esteem and self-perception to help the students to achieve their full potential. - To stimulate physical, mental, and socioaffective areas in the human being through the use of bodily exercises in the classroom. -To facilitate musical knowing and the development of rhythmic skills through the practice of body percussion. - To promote the performance of Colombian traditional music in nonconventional settings with advanced technical resources. The A Dos Music Project visited 12 cities in the Andean, Pacific, Amazonian, and Caribbean regions of Colombia, offering workshops, masterclasses, private lessons, lectures, and interactive concerts to communities of local music programs with social missions. The main activity offered by ADMP was a workshop designed to combine traditional music arranged for two clarinets and body percussion patterns specifically designed to emulate the percussion section of the traditional genres of the porro and the pasillo. The tour took place from July 6 to 29, 2017, and reached around 450 children and youth from 14 different music programs with great needs.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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  • Música

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A Dos Music Project A Report of the First National Music Education Tour in Colombia

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Imagen de apoyo de  Dynamic Demand Control of flexible household appliances a decentralized frequency regulation strategy based on a Neural Network architecture and Genetic Algorithms = Control dinámico de la demanda de electrodomésticos flexibles una estrategia descentralizada de regulación de frecuencias basada en una arquitectura de red neuronal y
algoritmos genéticos

Dynamic Demand Control of flexible household appliances a decentralized frequency regulation strategy based on a Neural Network architecture and Genetic Algorithms = Control dinámico de la demanda de electrodomésticos flexibles una estrategia descentralizada de regulación de frecuencias basada en una arquitectura de red neuronal y algoritmos genéticos

Por: Daniel José Sánchez Muñoz | Fecha: 2020

Abstract: This Master thesis presents a decentralized DDC strategy for major household appliances in Berlin. It exploits their power flexibility by means of three key indicators and supported by artificial intelligence. It has been examined whether those appliances may be used in a decentralized frequency regulation successfully. The appliances have been divided into two groups according to their operating characteristics- Thermal and Sequential Loads. This work also inquiries about the suitability of the control strategy to overcome power imbalances caused by PV generation. To answer this question, different seasonal and consumption scenarios have been analyzed. The control strategy is implemented using a modular approach. For this purpose, three main stages have been defined and divided into smaller units. For the implementation of these units Pandapower, MATLAB, and its toolbox MATPOWER have been used. The first stage is the power consumption forecast using a Neural Network. A feed-forward Network has been designed to estimate a day-ahead consumption profile for each household. At the second stage the Sequential Loads optimal scheduling takes place. A Genetic Algorithm optimizes the Sequential Loads turn on time based on householder preferences and characteristics. At the last stage the Dynamic Demand Control strategy takes place. On one hand, LSI stands for the characteristics of the appliances and for the user´s comfort. On the other hand, GSI and GCI represent the grid state from a technical and economic point of view. To validate the method a suitable network has been implemented. This network has 1800 households and includes 198 residential rooftop PV systems. Besides, several scenarios have been designed to test and compare the control strategy under different conditions. Influencing factors such as Energy Consumption Patterns and the size of the higher-level distribution grid are been modified. The analysis of the simulations shows that the proposed DDC strategy succeeds in frequency stabilization with flexible loads. The Energy Consumption Patterns play a relevant role to achieve this regulation. ECP d- the most realistic pattern, allows a successful control during the entire year with a significant low X value equal 10. These positive results allow for the conclusion that a decentralized control strategy with no information exchange can be implemented in a city like Berlin. Resumen: Esta tesis de maestría presenta una estrategia de control dinámica de demanda descentralizada para los principales electrodomésticos en la ciudad de Berlín. Esta estrategia explota la flexibilidad energética de los electrodomésticos mediante tres indicadores clave y al apoyarse en inteligencia artificial. Se ha examinado si esos aparatos pueden utilizarse con éxito en la regulación de frecuencia descentralizada. Los aparatos se han dividido en dos grupos según sus características de funcionamiento: cargas térmicas y secuenciales. Este trabajo también indaga sobre la idoneidad de la estrategia de control para superar los desequilibrios energéticos provocados por la generación fotovoltaica. Para responder a esta pregunta se han analizado diferentes escenarios estacionales y de consumo. La estrategia de control se implementa mediante un enfoque modular. Para ello, se han definido tres etapas principales y se han dividido en unidades más pequeñas. Para la implementación de estas unidades se han utilizado Pandapower, MATLAB y su aplicativo MATPOWER. La primera etapa es la pronostico del consumo de energía mediante una red neuronal. Se ha diseñado una red feed-forward para estimar el perfil de consumo diario para cada hogar. En la segunda etapa tiene lugar la programación óptima de cargas secuenciales. Un algoritmo genético optimiza el tiempo de activación de las cargas secuenciales en función de las preferencias y características del hogar. En la última etapa se lleva a cabo la estrategia de control dinámico de la demanda. Por un lado, LSI representa las características de los electrodomésticos y la comodidad del usuario. Por otro lado, GSI y GCI representan el estado de la red desde un punto de vista técnico y económico. Para validar el método se ha implementado una red adecuada. Esta red tiene 1800 hogares e incluye 198 sistemas fotovoltaicos residenciales en tejados. Además, se han diseñado varios escenarios para probar la estrategia de control en diferentes condiciones. Se modifican factores de influencia como los Patrones de Consumo de Energía y el tamaño de la red de distribución de nivel superior. El análisis de las simulaciones muestra que la estrategia DDC propuesta tiene éxito en la estabilización de frecuencia con cargas flexibles. Los Patrones de Consumo de Energía juegan un papel relevante para lograr esta regulación. ECP d- el patrón más realista, permite un control exitoso durante todo el año con un valor X bajo significativo igual a 10. Estos resultados positivos permiten concluir que una estrategia de control descentralizado sin intercambio de información se puede implementar en una ciudad como Berlín.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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  • Ingeniería

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Dynamic Demand Control of flexible household appliances a decentralized frequency regulation strategy based on a Neural Network architecture and Genetic Algorithms = Control dinámico de la demanda de electrodomésticos flexibles una estrategia descentralizada de regulación de frecuencias basada en una arquitectura de red neuronal y algoritmos genéticos

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Imagen de apoyo de  Minimising the Inclusion and Exclusion Errors to Design Targeting Indices: Between income-based weights and normative weights

Minimising the Inclusion and Exclusion Errors to Design Targeting Indices: Between income-based weights and normative weights

Por: Lina María Sánchez-Cespedes | Fecha: 2018

Abstract: One of the strategies to improve governments’ allocation of resources, particularly when these are insufficient to meet all the public needs, is the use of targeting indices. Generally, a targeting index is a linear combination of wellbeing indicators (for example years of education, dwelling conditions, and so forth) that orders the members of the population according to their living conditions to classify and identify the beneficiaries of social programmes. The weighting method that we propose maximises a function that depends on the number of poor beneficiaries, by income and/or expenditure, given some normative restrictions. Therefore, the indices designed with this method target poor people taking into consideration not only the income dimension, but also other dimensions, such as health, nutrition, and dwelling, although they are not correlated with income and/or correlated with one another. The method for taking these dimensions into account is to specify weighting restrictions by an indicator of wellbeing. In other words, we establish maximum and minimum values for the weights according to the number of indicators and the needs of social programmes. These values maintain the balance between income-based weights and normative weights. Because of these characteristics, we call our method Maximising Poor Beneficiaries with Normative Restrictions (MPBR). The algorithm behind MPBR can maximises or minimises any function. For instance, in the first exercise of this study, it exclusively counts the number of expenditure -poor beneficiaries, and in the second it contemplates both income-poor and expenditure-poor beneficiaries, given double weight to those that meet both conditions - thus the poorest of the poor households become the first beneficiaries of social programmes-. We find that when the function to maximise counts exclusively the number of income-poor (or expenditure-poor) households before a cutoff, it is equivalent to minimising the IE (Inclusion error) and EE (Exclusion error). In fact, we theoretically and empirically demonstrate that the models that minimise the IE and EE (considering income-poor or expenditure-poor households) are probabilistic models. Therefore, we conclude that probabilistic models are a useful tool to determine approximately the minimum IE and EE that can be obtained with a set of indicators. Applying MPBR, we find that when the increase in an indicator of wellbeing statistically increases the probability of not being expenditure-poor, the weight of the indicator converges to a specific positive value to maximise the number of expenditure-poor beneficiaries; in contrast, if the increase in an indicator statistically decreases this probability, the weight of the indicator converges to the minimum allowed weight. In the case in which the indicator is not statistically significant in the probabilistic model, its weight does not converge to a specific value. However, when the weighting restrictions become stronger (for example a greater minimum weight), most of the weights converge to a value. In a comparison of MPBR with other weighting methods (for example PCA and normative method), we conclude that the index estimated with MPBR has a smaller IE and EE and distributes the weights between indicators more equitably than the indices calculated with other methods.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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  • Economía

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Minimising the Inclusion and Exclusion Errors to Design Targeting Indices: Between income-based weights and normative weights

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Imagen de apoyo de  Applications of conventional tunneling methods in Terzo Valico dei Giovi project, study cases Vallemme and Moriassi Tunnels

Applications of conventional tunneling methods in Terzo Valico dei Giovi project, study cases Vallemme and Moriassi Tunnels

Por: Juan David Salazar Díaz | Fecha: 2019

Abstract: Terzo Valico dei Giovi is a huge railway project covered by more than 90 km of tunnels between Milano and Genova, to join the net of high speed and high capacity trains, part of the Rhine Alpine corridor of the Trans European Transport Network (TEN-T) to connect the main economical capitals of Europe improving the performance of transport and merchandise trade. The present study is according to the methodology used for ADECO-RS applied in the tunnels from Terzo Valico dei Giovi, referred about the support and the tunneling conventional method foreseen in DT2 (Direzione Tronco Piemonte) with the jobsites studied cases about DCP2 (Direzione Cantiere Piemonte 2). The thesis proposes to describe the Terzo Valico dei Giovi project with the technical and organizational aspects of conventional tunneling related to Vallemme and Moriassi jobsites. In addition, a description of the case studied about excavation in the presence of gas methane flow (Grisou) and the problem/solving encountered during the cycle excavation, the production activities and the management of Quality, Safety and Environment.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Applications of conventional tunneling methods in Terzo Valico dei Giovi project, study cases Vallemme and Moriassi Tunnels

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Imagen de apoyo de  Introducción al modelado y simulación del electrodo transparente con CNTs en celdas solares orgánicas

Introducción al modelado y simulación del electrodo transparente con CNTs en celdas solares orgánicas

Por: Caterin Yojana; Villa Ramírez Salas Redondo | Fecha: 2012

Abstract: La fabricación de las celdas fotovoltaicas inorgánicas son aquellas cuyo semiconductor es a base de material inorgánico (Si, AsGa, CuInS2, CIS, CdTe), son poco económicas, por ende, es necesario hallar una manera de producir celdas solares sin que la inversión económica sea costosa. Debido a esta dificultad tecnológica, se ha optado por usar semiconductores orgánicos en la fabricación de las celdas. Los paneles solares orgánicos no se contemplan como un sustituto a los de silicio como material semiconductor, sino un complemento para crear mejores fuentes de energía. En este caso, se plantea el uso de los nanotubos de carbono (CNT) como material semiconductor en la fabricación de celdas fotovoltaicas orgánicas.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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  • Tecnología

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Introducción al modelado y simulación del electrodo transparente con CNTs en celdas solares orgánicas

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Imagen de apoyo de  Transistores basados en nanotubos de carbono

Transistores basados en nanotubos de carbono

Por: Caterin Yojana; Villa Ramírez Salas Redondo | Fecha: 2009

Resumen: Las aplicaciones de la electrónica exigen mayor eficiencia de los dispositivos electrónicos que se utilizan hoy en día. Entre los aspectos mas importantes esta el área ocupada por un circuito: Se busca que los dispositivos electrónicos ocupen el menor espacio posible. La tecnología que se utiliza hoy en día para fabricar dispositivos semiconductores está llegando a un punto limite, donde cada vez es mas difícil obtener reducción en el tamaño sin afectar otras características del dispositivo. La nanoelectrónica está evolucionando a un punto donde se hace posible la construcción de dispositivos semiconductores que presenten mejores características que los fabricados en la actualidad. Este documento muestra una revisión bibliográfica sobre nanotecnología, con el fin de presentar una propuesta de investigación para implementar transistores basados en nanotubos de carbono. Este trabajo está en su fase inicial, se espera que a finales del 2009 se tenga una metodología de implementación de transistores utilizando nanotecnología.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Transistores basados en nanotubos de carbono

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Imagen de apoyo de  Adaptação de Helicoverpa armigera aos inibidores de peptidase de soja envolve uma alteração no padrão de expressão das serino peptidases e sugere um controle
epigenético

Adaptação de Helicoverpa armigera aos inibidores de peptidase de soja envolve uma alteração no padrão de expressão das serino peptidases e sugere um controle epigenético

Por: Pedro Alexander Velásquez Vasconez | Fecha: 2021

Resumo: Após décadas das primeiras publicações sobre a plasticidade transcricional do sistema digestivo dos insetos polífagos, ainda não se conhece em profundidade como os genes são regulados e as vias de sinalização envolvidas neste mecanismo adaptativo. Inicialmente, foi mostrado que a adaptação de lagartas de H. armigera à alimentação com inibidores de peptidase de soja (IPs) se deve à alteração do perfil transcricional de genes codificadores de serino peptidases do sistema digestivo. A presença dos IPs na dieta causou mudanças na regulação de genes de um amplo repertório de enzimas proteolíticas, principalmente com o aumento de genes de tripsinas. A regulação diferencial de enzimas digestivas foi associada à adaptação da H. armigera ao efeito anti-nutricional dos IPs. Além disso, a análise de dados de expressão gênica em larga escala (RNA-seq) mostrou que aproximadamente 40% dos transcritos (cerca de 500 epialelos potenciais) induzidos pelos IPs foram transmitidos à geração seguinte, apesar das lagartas desenvolverem-se em dietas desprovidas de IPs. A fim de caracterizar um possível mecanismo epigenético responsável por este mecanismo adaptativo, foi realizado o metiloma do sistema digestivo das lagartas da primeira geração (alimentadas com e sem IPs) e das progênies de lagartas expostas aos IPs. Epialelos de metilação do DNA foram associados aos controles transcricional e traducional, sugerindo um possível envolvimento da alteração do padrão de metilação na adaptação de H. armigera aos IPs. Este trabalho abre novas perspectivas no entendimento do polifagismo e a plasticidade dos insetos na alimentação de um amplo número de plantas hospedeiras, influenciando o seu curso evolutivo.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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  • Ciencias naturales

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Adaptação de Helicoverpa armigera aos inibidores de peptidase de soja envolve uma alteração no padrão de expressão das serino peptidases e sugere um controle epigenético

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Imagen de apoyo de  History

History

Por: María Catalina; Díaz Pabón Jiménez Jiménez | Fecha: 2019

Abstract: The history of Colombia has been defined by the paradox of the coexistence of violence and economic growth. While the economy of the country has grown almost uninterruptedly since the middle of the 20th century, in 2019 the state was still not fully capable of reasserting its presence nor of providing justice or security for all of its citizens across its territory. This chapter analyses the paradox of the coexistence of armed violence and economic growth in Colombia, in which parts of the elite sections of the country benefit by the lack of security and justice. Violence is good for business, although not good for statehood.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Otros
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History

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Imagen de apoyo de  Life cycle assessment of perovskite on silicon tandem PV modules at industrial scale

Life cycle assessment of perovskite on silicon tandem PV modules at industrial scale

Por: Caterin Yojana; Blanco Salas Redondo | Fecha: 2020

Abstract: For the first time a comprehensive life cycle assessment (LCA) is reported of a large-area perovskite/Si tandem photovoltaic (PV) module of about 2 m², with an assumed power conversion efficiency of 30%, 30 years lifetime and an annual degradation of 0.5%, manufactured in a 1 GW production plant. By means of the LCA method, we calculate the contribution to the International Reference Life Cycle Data System (ILCD) impact categories associated with a perovskite/Si tandem PV system compared with a passivated emitter and rear cell (PERC) used as reference. We consider a functional unit of 1 kWh of generated direct current electrical energy from the tandem module over its lifetime. It was found that the most significant environmental hotspots are the silicon wafer production and the balance of system (BOS), especially the mounting system, inverter and electric installation. Overall, the impact contributions to the environment caused by the perovskite sub-module are below 1% throughout all the ILCD categories in focus: climate change, freshwater ecotoxicity, water resource depletion and human toxicity. Even the contribution of lead to human toxicity is just about 0.01%. For all the impacts assessed, the perovskite/Si tandem shows a decrease of between 17-20% of the contributions to each impact category compared to the PERC-module based reference PV system, if the Si bottom sub-module has an initial cell efficiency of at least 22% with 1% cell-to-module (CTM) loss, and the perovskite top sub-module has a minimum initial cell efficiency of 18% with at most 5% CTM loss and a transmittance near IR region larger than 80%. The key result found in this work is the relevance of the performance and reliability of the PV system to achieve lower environmental impacts. A comparison between optimistic, realistic, and pessimistic scenarios was performed to investigate this matter: in the worst-case scenario, the environmental impact of the PV tandem system would have a general 50% increase throughout all ILCD impact categories against the realistic case, whereas in the optimistic one, the results suggest a reduction of 46% to the global impact contributions, compared to the realistic scenario.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Life cycle assessment of perovskite on silicon tandem PV modules at industrial scale

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Imagen de apoyo de  Simultaneous fluorescence and phosphorescence from organic molecules

Simultaneous fluorescence and phosphorescence from organic molecules

Por: Caterin Yojana; Reineke Salas Redondo | Fecha: 2015

Diluting organic molecules in a polymer matrix material suppresses non-radiative behavior, leading to biluminescence, wherein light is emitted efficiently from both singlet and triplet states. In summary, biluminescence has developed into a thoroughly optimized and unique emissive system. Among the characteristics obtained through this system, the most significant is the ability of biluminophores to offer direct access to the radiative states of both spin manifolds (singlets and triplets) in organic molecules without the requirement for special or complex material combinations. As a result, an exciton is given the chance to re-emit its energy, regardless of its initial state. In future work, we intend to increase the toolset of organic biluminophores by screening materials to determine the structure-property relationships behind persistent phosphorescence, and to identify molecular building blocks that are suitable for the development of future materials. In addition, we will intensify our exploration of biluminescence for future applications (e.g., sensing).
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Simultaneous fluorescence and phosphorescence from organic molecules

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