First evidence of resistive switching in polycrystalline GaV4S8 thin layers

Recently a new type of reversible and non-volatile resistive switching was discovered in single crystals of Mott insulators AM4X8 (A = Ga, Ge; M = V, Nb, Ta; X = S, Se). Here we report on the first synthesis of thin layers (thicknesses in the 100 to 1000 nm range) of GaV4S8 by RF magnetron sputtering process. Energy dispersive spectroscopy, X-ray diffraction and TEM analyses attest the high quality of polycrystalline GaV4S8 thin layers. Electrical measurements demonstrate that deposited GaV4S8 thin films exhibit a non-volatile reversible resistive switching at room temperature with writing/erasing times of ~10 μs and a memory window (Rhigh – Rlow)/ Rlow > 33%

Using Green Chemistry to Build Community: How Transformational Learning Impacts the Building of a Community of Practice

Green Chemistry education is a widening field, seeking to include educators at all levels collaboratively in the process of transforming outdated chemistry practices. Qualitative research methods were used to interview three key collaborator groups at Beyond Benign, a green chemistry education organization, who are considered part of the Green Chemistry Community of Practice (GCCoP). This was done to develop a strategic plan to 1) explore how the Beyond Benign team and K-12 teachers see themselves as part of one GCCoP; 2) to ascertain how to bring the K-12 program into alignment with the organization’s evolving mission; and 3) to discover approaches for improving K-12 and Higher Ed collaboration and engagement, creating new possibilities for K-12, and bringing the two communities back into one evolving GCCoP. What was discovered through interviews with the Beyond Benign team, K-12 teachers, and higher ed faculty was that there were several challenges, but many possibilities for collaboration. Transformational learning that generates engagement, agency, and a desire for change was a theme that educators at all levels, from elementary through grad school, described as important to learning and building community around green chemistry to generate changes in the wider world, and draw more people into GCCoP

Field trialling of a pulse airtightness tester in a range of UK homes

A new low pressure ‘quasi-steady’ pulse technique for determining the airtightness of buildings has been developed further and compared with the standard blower-door technique for field-testing a range of typical UK homes. The reported low pressure air pulse unit (APU) has gone through several development stages related to optimizing the algorithm, pressure reference and system construction. The technique, which is compact, portable and easy to use, has been tested alongside the standard blower-door technique to measure the airtightness of a range of typical UK home types. Representative of the UK housing stock, the homes mostly have low levels of airtightness, resulting in poor energy performance, poor indoor air quality and poor thermal comfort. Some of these homes have been targeted for retrofitting and a quick, low cost and simple method for accurately determining their airtightness has clear advantages for correctly predicting the benefits of any improvements. A comparison between the results given by the two techniques is presented and the field trials indicate that the latest version of the pulse technique is reliable for determining building leakage at low pressure. Repeatability of multiple APU tests in the same house is found to be within +/-5% of the mean. A test where the leakage is increased by a known amount shows the APU is able to measure the change more accurately than the blower-door test. The APU also gives convenience in practical applications, due to being more compact and portable, plus it doesn’t need to penetrate the building envelope. The field trials demonstrate the pulse test has the potential to be a feasible alternative to the standard blower-door test

Laboratory Testing of Aerosol for Enclosure Air Sealing

Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage

Proyecto para la capacitación en los procesos evaluativos del proceso de selección laboral, para los usuarios de la Startup Aleia

164 páginasIn this document, a problem was developed for the Aleia by Séligo organization that presented difficulties with its candidates to be hired by companies, for which an educational project was implemented to improve knowledge in the evaluation of the selection process in clients of The company, given the user problems that arose in the selection processes, had difficulties advancing within said evaluation processes, an educational project was developed basing its design and execution on the logical framework methodology, a virtual school was implemented asynchronous, which had the educational strategy of the inverted classroom, this project was evaluated with the CIPP model, which allowed the organization to validate a training system that allowed users to grow in knowledge about evaluation processes, this increased the performance of the students. users in selection processes.En este documento se desarrolló una problemática de la organización Aleia by Séligo que presentaba dificultades con sus candidatos para ser contratados por parte de las empresas, por la cual se implementó un proyecto educativo para mejorar el conocimiento en la evaluación del proceso de selección en clientes de la compañía, dadas las problemáticas de los usuarios que se presentaban en los procesos de selección, tenían dificultades para avanzar dentro de dichos procesos evaluativos. En consecuencia, se desarrolló un proyecto educativo basando su diseño y ejecución en la metodología del marco lógico, se implementó una escuela virtual asincrónica, que tenía la estrategia educativa del aula invertida, este proyecto fue evaluado con el modelo CIPP, que le permitió a la organización validar un sistema de capacitación y a los usuarios crecer en el conocimiento sobre procesos evaluativos e incrementar el rendimiento en los procesos de selección.Maestría en Proyectos Educativos mediados por TICMagíster en Proyectos Educativos mediados por TI

Energy impacts of attic duct retrofits in Sacramento houses

Inefficiencies in air distribution systems have been identified as a major source of energy loss in US sunbelt homes. Research indicates that approximately 30--40% of the thermal energy delivered to the ducts passing through unconditioned spaces is lost through air leakage and conduction through the duct walls. Field experiments over the past several years have well documented the expected levels of air leakage and the extent to which that leakage can be reduced by retrofit. Energy savings have been documented to a more limited extent, based upon a few field studies and simulation model results. Simulations have also indicated energy loss through ducts during the off cycle caused by thermosiphon-induced flows, however this effect had not been confirmed experimentally. A field study has been initiated to separately measure the impacts of combined duct leak sealing and insulation retrofits, and to optimize a retrofit protocol for utility DSM programs. This paper describes preliminary results from 6 winter and 5 summer season houses. These retrofits cut overall duct leakage area approximately 64%, which translated to a reduction in envelope ELA of approximately 14%. Wrapping ducts and plenums with R-6 insulation translated to a reduction in average flow-weighted conduction losses of 33%. These experiments also confirmed the appropriateness of using duct ELA and operating pressures to estimate leakage flows for the population, but indicated significant variations between these estimates and measured flows on a house by house basis. In addition, these experiments provided a confirmation of the predicted thermosiphon flows, both under winter and summer conditions. Finally, average material costs were approximately 20% of the total retrofit costs, and estimates of labor required for retrofits based upon these experiments were: 0.04 person-hrs/cm{sup 2} of duct sealed and 0.21 person-hrs/m{sup 2} of duct insulated

Prepuesta de implementación del área auditoría interna Cervecería Brumar S.A.S

El presente trabajo de grado se realizó en BRUMAR S.A.S, con el objeto de estructurar una propuesta para la creación del área de auditoría interna y así poner en práctica todo lo concerniente al tema del control interno en las empresas. Este proyecto es de carácter analítico y diagnóstico, se enfoca en el desarrollo de actividades que buscan una herramienta gerencial para formalizar el control interno, generar un nivel de confianza en los asociados frente a todos los procesos de la empresa que usa para el manejo de los recursos

Equipamiento Centro Agro-Cultural Villa del Cerro - Chapinero

El tema principal proviene del análisis fundamental, de cómo se ha desarrollado el crecimiento urbano en Bogotá, la carencia de agricultura y sostenibilidad como medida para la evolución urbana, para lo cual se plantea un equipamiento Agro-Cultural ubicado en la periferia urbana de Bogotá en el barrio Villa del Cerro, con el fin de suplir necesidades de carácter cultural, físico espaciales atendiendo al déficit de espacio Público, de carácter agrícola, fomentando educación y estrategias que podrán ser aplicadas en la ciudad mejorando el ecosistema natural y urbano