Transformación del casco urbano de Villa de Leyva a partir de una tipología arquitectónica y urbana progresiva

Trabajo de gradoVilla de Leyva se establece como un punto fundamental para proponer nuevas posturas arquitectónicas, es decir, de cómo se podría reinterpretar, restablecer, revitalizar y proponer distintas variables para intervenir un Municipio (Villa de Leyva) el cual tiene cualidades únicas en temas arquitectónicos, urbanos y la plena conciencia de lo que representa la arquitectura típica colonial y como le da condiciones únicas a un territorio que deriva en la reinterpretación tipológica que arroja resultados específicos de trasformación.RESUMEN 1. INTRODUCCIÓN 2. PREGUNTAS ORIENTADORAS 3. HIPÓTESIS. 4.OBJETIVOS 5.OBJETIVO GENERAL 6.OBJETIVO ESPECIFICOS 7.MARCO TEÓRICO Y CONCEPTUAL 8.MARCO TEORICO 9.MARCO CONCEPTUAL 10.METODOLOGÍA 11.ANALISIS DEL SECTOR. 12.POBLACION OBJETO 13.CONCEPTO DE DISEÑO 14.PROCESO COMPOSITIVO 15.RESULTADOS 16.DISCUSIÓN 17.CONCLUSIONES 18.REFERENCIAS 19.ANEXOSPregradoArquitect

Tin Oxides: New anodes for Li-Ion cells

La reacción entre el litio y óxidos o aleaciones de estaño es reversible cuando se realiza por métodos electroquímicos y a bajos potenciales con respecto al electrodo de litio. Esta propiedad permite el uso de estos materiales como electrodos negativos en el diseño y construcción de baterías tipo ion-litio. En el caso de óxidos de estaño la reacción de inserción de litio en la matriz conduce a la formación de aleaciones Li-Sn. La presencia de agregados grandes de átomos de estaño, formados durante la inserción de litio, origina la fragmentación y el desmoronamiento del material anódico. Este efecto provoca la pérdida del contacto eléctrico entre partículas, con el consiguiente deterioro de la batería. La optimización del rendimiento electroquímico de estos materiales se puede lograr mediante el control del crecimiento y tamaño de los agregados de estaño.The electrochemical reaction between Li and tin-based compounds, is reversible and takes place at low potentials measured against the Li electrode. This feature allows the use of these materials as negative electrodes in the manufacturing of Li-ion batteries. The lithium insertion in the tin oxides leads to the formation of Li-Sn alloys. The presence of large tin clusters, formed during the reaction, causes the cracking and crumblimg of the anodic material and the electronic contact between the particles is lost. The electrochemical performance of these materials can be optimized by controlling the growing and size of tin aggregate

Construcción de sistemas de numeración. Propuesta para un aula inclusiva 

Los sistemas de numeración a lo largo de la historia han sido quizás los elementos más importantes en el desarrollo del saber matemático junto con la geometría; en esta propuesta para un aula inclusiva, se plantea un recorrido no solo desde la historia de la matemática, sino desde la didáctica en donde utilizando la teoría de situaciones didácticas de Brousseau se propone una secuencia que muestra en los estudiantes de grado sexto la evolución de los sistemas de numeración y el porqué de la escogencia del sistema posicional decimal que utilizamos. Estas actividades se diseñan utilizando recursos manipulativos tangibles en un aula inclusiva partiendo de una experiencia previa con estudiantes con limitación visual en el colegio OEA, donde se buscó acercar a los estudiantes a conceptos aditivos, multiplicativos, manejo de bases, posición y escritura polinomial

Ecologically Designed Sanitary Sewer Based on Constructed WetlandsTechnology – Case Study in Managua (Nicaragua)

In developed countries the sanitation and treatment of urban wastewater is well sustained and technically solved by means of conventional pipe networksandsubsequentcentralizedtreatments.However,developingcountries lack these infrastructures and are in need of sustainable, decentralized and economically viable solutions for the disposal of their urban wastewaters. In addition to this, there are situations where the demands of conservation of naturalspacesdonotallowintensiveconstructiveproceduresandwhichforce the implementation of sanitary engineering with less environmental impact. We present the Ecological Wastewater Sewer (EWS), an ecological urban sewerage system that simultaneously transports wastewater and improves its quality.Thisinnovativetechnologyisanalternativetoconventionalsanitation piping that has minimal environmental impact. It is based on a successful previous work for the improvement of artificial wetlands in a pilot scheme andatfull-scaleonatestsite.TheEWSisachannel-shapeddevicethatrelies on the application of two key developments: a carefully designed cornered stones layout, and the creation of a natural aeration system. This way, it acts as a separating sewage system that guarantees the presence of a chamber of circulating air within the transportation unit, favouring permanent aerobic conditions in the upper levels of the mass of wastewater. Furthermore, its capacity to set tle suspended solids allows the EWS to be used as a sedimentor in water purification processes. A real-life application of this system proved successful in the sanitation of a district of Managua (Nicaragua). Working with a 100-metre-long street of 20 one-story houses, the system is reported to still be in full operating order after six years. The conclusions and results drawn from its monitoring are meticulously explained in our paper, as well astherecommendations&guidelinesforthedesignofmoreEWSunits,with aim to the popularization of this affordable, efficient and green approach to wastewater sanitation.Andalusian International School of Water Engineering, City hall of SevilleCooperation Office at the University of Sevill

Biomass Porous Carbons Derived from Banana Peel Waste as Sustainable Anodes for Lithium-Ion Batteries

Disordered carbons derived from banana peel waste (BPW) were successfully obtained by employing a simple one-step activation/carbonization method. Different instrumental techniques were used to characterize the structural, morphological, and textural properties of the materials, including X-ray diffraction, thermogravimetric analysis, porosimetry and scanning electron microscopy with energy-dispersive X-ray spectroscopy. The chemical activation with different porogens (zinc chloride, potassium hydroxide and phosphoric acid) could be used to develop functional carbonaceous structures with high specific surface areas and significant quantities of pores. The BPW@H3PO4 carbon exhibited a high specific surface area (815 m2 g−1), chemical stability and good conductivity for use as an anode in lithium-ion batteries. After 200 cycles, this carbon delivered a reversible capacity of 272 mAh g−1 at 0.2 C, showing a notable retention capacity and good cycling performance even at high current densities, demonstrating its effectiveness and sustainability as an anode material for high-energy applications in Li-ion batteries

Defensive behavior of Dipsas sanctijoannis (Serpentes: Dipsadidae)

Herein, we report the defensive behavior of Dipsas sanctijoannis (Boulenger, 1911) for first time, based on observations of three different individuals in the Municipality of Manizales, Departamento de Caldas, Colombia

Estudio del hueso de oliva como fuente de carbón para baterías de litio

III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

Nuevos materiales compuestos Si/carbono grafitizado como electrodos negativos de alta energía para baterías de litio-ión

II Encuentro sobre nanociencia y nanotecnología de investigadores y tecnólogos de la Universidad de Córdoba. NANOUC

Towards Predicting Good Users for Biometric Recognition Based on Keystroke Dynamics

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-16181-5_54Proceedings in Computer Vision - ECCV 2014 Workshops held in Zurich (Switzerland) on 2015.This paper studies ways to detect good users for biometric recognition based on keystroke dynamics. Keystroke dynamics is an active research field for the biometric scientific community. Despite the great efforts made during the last decades, the performance of keystroke dynamics recognition systems is far from the performance achieved by traditional hard biometrics. This is very pronounced for some users, who generate many recognition errors even with the most sophisticate recognition algorithms. On the other hand, previous works have demonstrated that some other users behave particularly well even with the simplest recognition algorithms. Our purpose here is to study ways to distinguish such classes of users using only the genuine enrollment data. The experiments comprise a public database and two popular recognition algorithms. The results show the effectiveness of the Kullback-Leibler divergence as a quality measure to categorize users in comparison with other four statistical measures.This work has been partially supported by projects Bio-Shield (TEC2012-34881) from Spanish MINECO and BEAT (FP7-SEC-284989) from EU