Smart thermostats: an experimental facility to test their capabilities and savings potential

The European Commission has explained how heating and cooling in buildings and industry account for half of the energy consumption of the EU. Several studies explain how to achieve an energy saving at home, and the use of smart thermostats will help to reduce energy consumption while increasing the efficiency of households. In this article, a comparative evaluation was carried out between four smart thermostats that are now on the market, whose characteristics vary in terms of price, precision of measurements and set temperature, algorithms, etc. A thermal test chamber was designed and constructed from a refrigerator, a thermal blanket, a Raspberry Pi and the necessary electronic components for its control and data collection. From the tests carried out in the thermal chamber, data on the operation of the four thermostats such as the maintenance and the anticipation of the setpoint temperature, were obtained. It was necessary to run the system enough times for each thermostat to memorize the housing characteristics, such as its inertia and its thermal insulation. This would also allow for the generation of a better algorithm to regulate the temperature, which would create a lower oscillation with respect to the setpoint temperature. The learning of the thermostats was not demonstrated and for the anticipation mode it was seen that the thermostats failed to improve or learn in this aspect, as they did not improve the start-up times of the heating system, with the consequent increase in energy consumption.This work was supported by the Spanish Government under the R+D initiative INNPACTO with reference IPT-2011-1447-920000, Spanish R+D initiative with reference ENE-2013-42720-R and RETOS RTC-2015-3795-3

Dissolved gas analysis equipment for online monitoring of transformer oil: A review

Power transformers are the most important assets of electric power substations. The reliability in the operation of electric power transmission and distribution is due to the correct operation and maintenance of power transformers. The parameters that are most used to assess the health status of power transformers are dissolved gas analysis (DGA), oil quality analysis (OQA) and content of furfuraldehydes (FFA) in oil. The parameter that currently allows for simple online monitoring in an energized transformer is the DGA. Although most of the DGA continues to be done in the laboratory, the trend is online DGA monitoring, since it allows for detection or diagnosis of the faults throughout the life of the power transformers. This study presents a review of the main DGA monitors, single- or multi-gas, their most important specifications, accuracy, repeatability and measurement range, the types of installation, valve or closed loop, and number of analogue inputs and outputs. This review shows the differences between the main existing DGA monitors and aims to help in the selection of the most suitable DGA monitoring approach according to the needs of each case.This research was funded by the EU Regional Development Fund (FEDER) and the Spanish Government under RETOS-COLABORACIÓN RTC-2017-6782-3 and by the University of Cantabria Industrial Doctorate 19.DI12.649

Simple Detection of Large InDeLS by DHPLC: The ACE Gene as a Model

Insertion-deletion polymorphism (InDeL) is the second most frequent type of genetic variation in the human genome. For the detection of large InDeLs, researchers usually resort to either PCR gel analysis or RFLP, but these are time consuming and dependent on human interpretation. Therefore, a more efficient method for genotyping this kind of genetic variation is needed. In this report, we describe a method that can detect large InDeLs by DHPLC (denaturating high-performance liquid chromatography) using the angiotensin-converting enzyme (ACE) gene I/D polymorphism as a model. The InDeL targeted in this study is characterized by a 288 bp Alu element insertion (I). We used DHPLC at nondenaturating conditions to analyze the PCR product with a flow through the chromatographic column under two different gradients based on the differences between D and I sequences. The analysis described is quick and easy, making this technique a suitable and efficient means for DHPLC users to screen InDeLs in genetic epidemiological studies

Prevalence of risky eating behaviors and associated factors in indigenous population in Colombia

La información sobre conductas alimentarias de riesgo (CAR) entre indígenas latinoamericanos es escasa. El objetivo de este estudio fue estimar la prevalencia de CAR en población indígena de Colombia, así como identificar factibles factores de riesgo sociodemográficos e individuales. De la Encuesta Nacional de Salud Mental se retomaron los registros de 493 indígenas adultos (Medad = 29.5 años, DE = 7.39), hombres y mujeres. Las CAR evaluadas fueron: dieta restrictiva, malestar al comer, atracón y vómito autoinducido. El 19.5% de los participantes reportaron presentar al menos una CAR, y aquellas con mayor prevalencia fueron la dieta (8.5-9.6%) y el atracón (6.1%). Ninguno de los factores sociodemográficos evaluados se asoció a la presencia de CAR; por el contrario, de entre los factores individuales, la presencia de trastorno afectivo mostró ser un factible factor de riesgo de estas conductas. Las CAR no son infrecuentes en la población indígena adulta colombiana, e incluso su prevalencia puede duplicar la documentada en población general. Este estudio pretende aportar al escaso conocimiento existente sobre el tópico en poblaciones indígenas. Hallazgos que, ya sea a mediano o largo plazo, deberán incidir en el planteamiento de políticas de salud públicas acordes a las minorías indígenas presentes en Latinoamérica.Q4113-122Población indigenaData on risky eating behaviors (REB) in Latin American ethnic groups is scarce. The aim of this study was to determine the prevalence of REB in adult indigenous from Colombia, as well as to identify feasible sociodemographic and individual risk factors. A total of 493 records of adult indigenous men and women (Mage = 29.5 years, SD = 7.39) were retrieved from the National Survey of Mental Health. The REB assessed were: restrictive dieting, eating discomfort, binge-eating and self-induced vomiting. Participants (19.5%) reported having at least one REB, being restrictive dieting (8.5-9.6%) and binge eating (6.1%) those with higher prevalence. None of the sociodemographic factors evaluated was associated with the presence of REB, on the contrary, among the individual factors, the presence of affective disorder showed to be a feasible risk factor for these behaviors. The REB are common in the indigenous population in Colombia, even its prevalence may double the one reported in general population. This study aims to contribute to the scarce existing knowledge about the topic in indigenous populations. Findings that, whether in the medium or long term, should influence the approach of public health policies according to the indigenous minorities in Latin America

Las especies exóticas predominan en la flora leñosa urbana de Chile central

The expansion of cities promotes the replacement of local biotas with exotic species causing a decrease in global diversity.As urbanization continues to expand, efforts directed towards the conservation within urban landscapes could supportregional biodiversity conservation. The biogeographic region of central Chile displays a native flora of global importancebecause of its high endemism. Up to date, studies analysing the composition of the floras within the cities are scarce. Thepresent study aims at characterizing the compositional and distributional patterns of the ornamental flora of five cities ofcentral Chile (La Serena, Valparaíso, Santiago, Rancagua, and Talca). For this purpose, we sampled several streets andsquares recording all woody species. The species were then characterized by their biogeographical origin and incidence.It was recorded 302 species of which approx. 86% were exotic and 14% were native, a consistent pattern found in the fivecities studied; these results contrast with the European urban flora, where native species can usually overcome 50% of theplant species. Almost half of the exotic species had their origin in Asia (including Australasia, Temperate, and TropicalAsia), Europe, and North America. Consequently, the representation of the regional flora within the urban context is lowfor central Chile, with the native species registered, accounting for only 0.81% of the total species described for thecountry. Urban habitats could support regional biodiversity conservation, so a shift towards sustainable urban planningcould promote local biological conservation.La expansión de las ciudades promueve el reemplazo de biotas locales (nativas) por especies exóticas, lo que causa unadisminución en la diversidad. A medida que la urbanización continúa, los esfuerzos dirigidos a la conservación dentrode los paisajes urbanos podrían apoyar la conservación de la biodiversidad regional. La región biogeográfica de ChileCentral muestra una flora nativa de importancia mundial debido a su alto endemismo. No obstante, hasta la fecha haypocos estudios que analicen la composición de las floras dentro de las ciudades de esta región. El presente estudio analizala composición de la flora ornamental para cinco ciudades de Chile central: La Serena, Valparaíso, Santiago, Rancaguay Talca. Para ello realizamos un muestreo de calles y plazas de estas ciudades, registrando especies de plantas leñosas,distinguiendo su origen biogeográfico y su incidencia. Se registraron 302 especies de las cuales aprox. el 86% fueronespecies exóticas y el 14% nativas, patrón numéricamente consistente en las cinco ciudades estudiadas. Casi la mitad delas especies exóticas provienen de Asia (incluyendo Australasia y Asia tropical y templada), Norteamérica y Europa. Enconsecuencia, la representación de la flora regional dentro del contexto urbano es baja para el centro de Chile. Los habitatsurbanos podrían apoyar la conservación de la biodiversidad regional, por lo que un cambio hacia una planificación urbanasostenible podría promover la conservación biológica local

Dynamic rating management of overhead transmission lines operating under multiple weather conditions

Integration of a large number of renewable systems produces line congestions, resulting in a problem for distribution companies, since the lines are not capable of transporting all the energy that is generated. Both environmental and economic constraints do not allow the building new lines to manage the energy from renewable sources, so the efforts have to focus on the existing facilities. Dynamic Rating Management (DRM) of power lines is one of the best options to achieve an increase in the capacity of the lines. The practical application of DRM, based on standards IEEE (Std.738, 2012) and CIGRE TB601 (Technical Brochure 601, 2014) , allows to find several deficiencies related to errors in estimations. These errors encourage the design of a procedure to obtain high accuracy ampacity values. In the case of this paper, two methodologies have been tested to reduce estimation errors. Both methodologies use the variation of the weather inputs. It is demonstrated that a reduction of the conductor temperature calculation error has been achieved and, consequently, a reduction of ampacity error.This research was funded by the Spanish Government AND FEDER funds under the R+D initiative RETOS COLABORACIÓN 2015” with reference RETOS COLABORACIÓN RTC-2015-3795-3 and Spanish R+D initiative with reference ENE2013-42720-R

Thermal behaviour of medium-voltage underground cables under high-load operating conditions

The dynamic management of electric power distribution lines has become a topic of great interest at present. Knowledge of the ampacity of cables is fundamental to carrying out dynamic management. In this study, the ampacity of buried cables in different soil resistivities and depths was calculated. A small-scale model was built in the laboratory to simulate the operating conditions of a buried cable. With the experimental results, a numerical model based on the finite element method was validated to evaluate the ampacities calculated by two standards. A comparison was made between the ampacities calculated from the IEC 60287-1 and UNE 211435 standards and those obtained from the simulated model. In addition, a comparison was made regarding the steady-state temperatures obtained at each calculated ampacity. The results obtained from the simulated model design show that the ampacity calculation method of the IEC 60287-1 standard where drying-out of the soil occurs is the most accurate, and has the least risk of exceeding the maximum permissible cable temperature.This work was financed by the EU Regional Development Fund (FEDER) and the Spanish Government under ENE-2013-42720-R, RETOS-COLABORACION RTC-2015-3795-3 and SODERCAN/FEDER Proyectos Puente 2017 and by the University of Cantabria Industrial Doctorate 19.DI12.649. The authors also acknowledge support received from Viesgo

UBosque + CO2CERO®, una herramienta de la comunidad El Bosque para compensar su huella de carbono

A través de los diferentes tratados internacionales como el protocolo de Kyoto y el acuerdo de París se han incentivado acciones para la mitigación del cambio climático, así mismo varias organizaciones científicas, movimientos ambientalistas, instituciones no gubernamentales, entre otras, han desarrollado diferentes investigaciones y propuestas que contribuyan a este mismo fin.En este contexto, la siembra de árboles constituye una herramienta eficaz para la captación de toneladas de CO2eq en la atmósfera; y es por esto que la Universidad El Bosque ha querido unirse a esta causa, a través del fomento de la aplicación UBosque + CO2CERO® para los sistemas operativosmóviles IOS y Android que le permite a los usuarios calcular su huella de carbono, plantearse cómo influye su estilo de vida en el planeta y posteriormente compensarla a través de la adquisición de certificados de carbono.La aplicación “UBosque + CO2CERO®”, permite a las personas y organizaciones obtener en minutos un indicador de control sobre la cantidad de CO2eq generado por cada persona y cúal sería la compensación aproximada en número de árboles a plantar, medida que se quiere llevar a cabo por la unidad de gestión ambiental de la Universidad El Bosque, que a su vez busca concientizar a la comunidad universitaria para mitigar su impacto personal con la siembra de árboles

Estimativa da porosidade de argamassas de cimento e cal pelo método de cálculo de volumes

The presence of lime in mixed mortars is responsible for the increase in the demand for mixing water for a given consistency. The additional water, which is not consumed in the cement hydration, remains free in the system and when evaporating it leads to high porosity in the hardened mortar. This paper presents the method of volume calculation as a tool for estimating the porosity of mixed mortars through their constituents, including lime, as well as its correlation with relevant properties in the hardened state. The method presented proved to be adequate for predicting the properties that define the behavior of the rendering. The data suggest that this approach needs further research, involving issues not considered in the theoretical volume  calculation, such as the influence of shrinkage and carbonation.A presença de cal nas argamassas mistas é responsável pelo aumento na demanda de água de amassamento para uma dada consistência. A água adicional, que não é consumida na hidratação do cimento, permanece livre no sistema e, ao evaporar, dá origem a porosidade elevada da argamassa endurecida. Este trabalho apresenta o método do cálculo de volumes como uma ferramenta para estimar a porosidade de argamassas mistas a partir de seus constituintes, inclusive a cal, bem como sua correlação com propriedades relevantes no estado endurecido. O método apresentado mostrou-se favorável para a previsão de propriedades que definem o comportamento dos revestimentos de argamassa. Os dados apresentados sugerem continuidade e aprofundamento desta linha de estudo envolvendo aspectos não considerados no cálculo teórico de volume, tais como a influência da retração e da carbonatação nas argamassas

Rendimiento en la prueba de admisión a la universidad (Saber 11) de personas en y sin condición de discapacidad

Objetivo Comparar los resultados en la prueba Saber 11 (prueba estandarizada para la admisión en la mayoría de universidades de Colombia) entre los estudiantes con y sin discapacidad dentro de la misma institución educativa. Asimismo, comparar el rendimiento de los alumnos con problemas de audición, discapacidad visual y física. Métodos Se realizó un estudio de cohorte retrospectiva en la que se dividió a los estudiantes según su condición de discapacidad. Se anidó un caso-cohorte emparejando cada caso de discapacidad con su grupo de compañeros de colegio. Se calcularon las diferencias estandarizadas para comparar los grupos. Resultados Los estudiantes sin discapacidades se desempeñaron significativamente mejor que los estudiantes con discapacidad, es decir, los estudiantes con discapacidades obtuvieron puntajes más bajos que sus compañeros de clase. Conclusión Se necesita más investigación para investigar si el sistema educativo colombiano, los ajustes en las pruebas para esta población o las capacidades individuales de los alumnos son los factores subyacentes de la diferencia en los resultados de las pruebas.Q3138-148Objective Comparing standardized university admission scores between students with and without disability within the same school and also comparing the performance of students with hearing, visual and physical disability. Methods This was a retrospective cohort study which compared the test results of students with and without disabilities within the same school. A matched case-control study nested in a cohort was assembled. Standardized differences were calculated for comparing such scores. Results Students without disabilities performed significantly better than disabled ones(i.e. disabled students scored lower than their classmates). Conclusion Further research is needed to determine whether the Colombian educational system, adjustments made to tests for this population or students' individual skills were the factors underlying the difference regarding the test results