Milk production estimation in goats by the Fleischmann method

Four adaptations of Fleischmann"s method, utilized for the calculus of accumulated milk production at complete lactation are compared. 551 lactations of the Florida breed goat were employed from the first to the tenth lactation with monthly controls. The mean reference productions obtained with the adaptations were different (p<0.05). These differences obey to a different way in which the milk production is calculated principally from calving to first control and, from the last control to drying.Se comparan cuatro adaptaciones del método Fleischmann para el cálculo de la producción de leche acumulada a lactación completa. Se emplearon 551 lactaciones de cabras de raza Florida de primera a décima lactación con controles mensuales. Las producciones medias de referencia obtenidas con las adaptaciones fueron diferentes (p<0,05) debido a la distinta manera de plantear el cálculo de la producción de leche, principalmente desde el parto al primer control y del último control al secado

Estudio preliminar de las alteraciones del campo geomagnético natural provocadas por los materiales de construcción.

La perspectiva del arquitecto en los aspectos de calidad ambiental, y salud en un contexto sostenible, se amplía al considerar las radiaciones como elemento a tener en cuenta en el diseño arquitectónico. En ese sentido, además del confort higrotérmico y de la calidad del aire, se puede considerar la calidad electromagnética del espacio en relación a la salud de las personas. En este trabajo, se experimenta sobre la influencia del campo geomagnético en relación con diversos materiales de construcción, para ello se toman datos con un geomagnetómetro. Se observa que los materiales de construcción por sus propiedades magnéticas tienen la capacidad de modificar en mayor o menor medida el campo geomagnético natural sobre el cual se desarrolla la vida. Se concluye que la consideración de la relación entre la magnitud del campo geomagnético y los materiales de construcción puede formar parte del criterio de elección de materiales para una arquitectura saludable y sostenible

CIRCULAR ECONOMY AND ENVIRONMENTAL BEHAVIOUR: A SYSTEMATIC LITERATURE REVIEW

The circular economy is a top priority issue on the European green agenda. However, despite this topic having been studied for decades, there seem to be no clear ideas about how to carry out the strategies and actions that allow achieving the presupposed objectives. For this reason, this paper aims to offer a systematic literature review that might provide researchers with a synthesis paper on what has been studied so far. To achieve that, descriptive and bibliometric analyses were performed on the bibliographic data obtained from the Web of Science. That, together with the study of the most prominent extant pieces of work in the field, both historical and present, allow offering a comprehensive picture of the state of arts. Thus, the main conclusions are that there is no clear study trend and, consequently, efforts are dissipating. In addition, the problem of the budget limitation is acknowledged since it might prevent researchers from carrying out solid experiments that may allow finding general solutions to the problems derived from the implementation of circular economy strategies or actions

Análisis de los conocimientos y opiniones de profesores sobre la reforma integral educativa de la educación básica

En este artículo se presenta una revisión de la literatura en torno al liderazgo transformacional, la cultura organizacional y el cambio educativo. A partir de ella, se hace una reflexión sobre la vinculación que existe entre los tres elementos y la potencial interdependencia que ostentan en el contexto escolar. Para ello, en la primera sección, se sintetizan las teorías clásicas que contribuyeron a la construcción del concepto del liderazgo transformacional y el proceso que se siguió para la consolidación del mismo, a través de lo cual se enfatizan los elementos fundamentales de este tipo de líder y sus diferencias con el transaccional. En la segunda sección, se analiza el rol del líder transformacional en el contexto organizacional en un ambiente de cambio educativo; en ella, se destaca el papel que desempeña el líder transformacional en las instituciones educativas y se vincula con la cultura organizacional como un elemento contextual que eventualmente es interdependiente con este tipo de liderazgo. Finalmente se hace una reflexión sobre el estado del arte de la vinculación entre los tres constructos presentados y se proponen líneas potenciales de investigación que pueden contribuir al mayor conocimiento sobre la complejidad de la relación entre ello

Comparativa del comportamiento acústico entre fachadas multicapas ligeras y fachadas tradicionales

Los sistemas de fachadas multicapas ligeras presentan características favorables respecto al ahorro en el consumo energético, ya que presentan un excelente comportamiento térmico. Sin embargo, desde el punto de vista acústico, en general han sido poco estudiados. Los primeros datos que se tienen es que no suelen alcanzar los valores de aislamiento acústico requeridos en el Código Técnico de la Edificación (CTE) en entornos especialmente ruidosos. Por lo tanto, los objetivos principales de esta investigación son obtener sistemas de fachadas multicapas ligeras con un alto grado de aislamiento acústico, que puedan ser empleados en entornos ruidosos. Al mismo tiempo que presenten excelentes características térmicas, sin descuidar aspectos tan importantes como la sostenibilidad de los materiales, la industrialización, los costes, entre otros. En este artículo se explicará el proceso que se ha llevado a cabo para realizar una investigación relacionada con el comportamiento acústico de fachadas multicapas ligeras. Para ello se han empleado los métodos de medida del comportamiento acústico a ruido aéreo e intensimetría sonora. Una vez obtenidos estos resultados se realiza una comparativa entre las fachadas multicapas ligeras y las fachadas tradicionales

Direct Optimization of a PCI Express Link Equalization in Industrial Post-Silicon Validation

Post-silicon validation is a crucial industrial testing process in modern computer platforms. Post-silicon validation of high-speed input/output (HSIO) links can be critical for making a product release qualification. Peripheral component interconnect express (PCIe) is a high-performance interconnect architecture widely adopted in the computer industry, and one of the most complex HSIO interfaces. PCIe data rates increase on every new generation. To mitigate channel effects due to the increase in transmission speeds, the PCIe specification defines requirements to perform equalization (EQ) at the transmitter (Tx) and at the receiver (Rx). During the EQ process, one combination of Tx/Rx EQ coefficients must be selected to meet the performance requirements of the system. Testing all possible coefficient combinations is prohibitive. Current industrial practice consists of finding a subset of combinations at post-silicon validation using maps of EQ coefficients, which are obtained by measuring the eye height, eye width, and the eye asymmetries of the received signal. Given the large number of electrical parameters and the multiplicity of signal eyes that are produced by on-die probes for observation, finding this subset of coefficients is often a challenge. In order to overcome this problem, a direct optimization method based on a suitable objective function formulation to efficiently tune the Tx and Rx EQ coefficients to successfully comply with the PCIe specification is presented in this report. The proposed optimization approach is based on a low-cost computational procedure combining pattern search and Nelder-Mead methods to efficiently solve an objective function with many local minima, and evaluated by lab measurements on a realistic industrial post-silicon validation platform

Development and assessment of a prototype as an innovative method for teaching agricultural machinery

An educational variable‐rate application (VRA) sprayer was developed and laboratory tested at the University of Seville (Spain). It was designed and built during 2009 by the undergraduate engineering students in a Precision Agriculture course and used as a teaching model in an Agricultural Machinery course during 2010. The first stage involved mounting all the instrumentation, sensors, and the hydraulic system on a metal platform. The second stage involved mounting a DGPS receiver, flowmeter, automated application control system, and all necessary electrical connections to the platform. Preliminary calibration tests of the equipment at a constant speed of 0.375 m s‐1 (1.35 km h‐1) showed good performance for pressure (kPa) and application rate (L ha‐1) (R2 = 0.998, p < 0.001). To evaluate the teaching method based on the prototype, a short‐answer assessment test was conducted consisting of ten multiple‐choice questions, each with one possible correct answer. Data were analyzed using analysis of variance (ANOVA). The factors were the teaching method (TM), repeated course (R), and attended theory (AT). In addition, the effect of a covariate (number of times a student repeated the course) in the factors was controlled with an analysis of covariance (ANCOVA). The effect of teaching method was significant for the score on the VRA sprayer questions (SPS) variable and the score on the conventional sprayer questions (SCS) variable (p < 0.001 for both). The average success for students using the prototype sprayer was 86%, compared to 60% for those using a conventional sprayer. The total cost of the VRA prototype sprayer was 40% less than the cost of retrofitting a conventional sprayer with precision agriculture equipment. Since the students were engaged in their own learning, they maintained a high level of enthusiasm throughout the course when utilizing the VRA prototype sprayer. It has proved to be a complementary and beneficial alternative for improving the students' education in the Agricultural Machinery course

EEG signal processing in mi-bci applications with improved covariance matrix estimators

Article number 8688582n brain–computer interfaces (BCIs), the typical models of the EEG observations usually lead to a poor estimation of the trial covariance matrices, given the high non-stationarity of the EEG sources. We propose the application of two techniques that significantly improve the accuracy of these estimations and can be combined with a wide range of motor imagery BCI (MI-BCI) methods. The first one scales the observations in such a way that implicitly normalizes the common temporal strength of the source activities. When the scaling applies independently to the trials of the observations, the procedure justifies and improves the classical preprocessing for the EEG data. In addition, when the scaling is instantaneous and inde pendent for each sample, the procedure particularizes to Tyler’s method in statistics for obtaining a distribution free estimate of scattering. In this case, the proposal pro vides an original interpretation of this existing method as a technique that pursuits an implicit instantaneous power-normalization of the underlying source processes. The second technique applies to the classifier and improves its performance through a convenient regularization of the features covariance matrix. Experimental tests reveal that a combination of the proposed techniques with the state-of-the-art algorithms for motor-imagery classification provides a significant improvement in the classification results.Ministerio de Economía y Competitividad ( España) TEC2017-82807-

Design of beams and slabs of self-compacting concrete fittings working to flexion

Numerous experimental studies indicate that addition of fibers substantially increases the shear strength of concrete and mortar beams, and that stirrups and reinforcing fibers combination can be really effective. When steel fibers are used as a supplement or substitute for vertical stirrups or folded bars, we obtain the following characteristics: The fibers are distributed randomly by the volume of the concrete with a closer separation than can be achieved with the Armor; The tensile strength at first crack, the ultimate tensile strength and the shear friction resistance are increased

Sistema de monitorización de puertas y ventanas de un centro de datos con IoT

En este trabajo se presenta la construcción de un prototipo de un sistema de monitorización de puertas y ventanas a través de una plataforma IoT. El objetivo fue diseñar un sistema que reporte a un servidor en la nube el cambio de estado, abierta o cerrada, de tres puertas y dos ventanas de la sala de equipos del centro de datos. Los cambios de estado son registrados por el servidor y por medio de una interfaz de usuario se muestran en línea los estados de las puertas y ventanas. La arquitectura del sistema se basa en una red inalámbrica de sensores integrada por un nodo central y cinco nodos de monitorización. Los nodos de monitorización están compuestos por una tarjeta PyBoard, dos sensores digitales de efecto Hall y una interfaz inalámbrica wifi. Al detectar un cambio de estado en puertas y ventanas, los nodos de monitorización lo notifican al nodo central, y este lo transmite al servidor por medio de un punto de acceso wifi. Cuando una puerta o ventana permanece abierta más de un período de tiempo configurable, se envía un mensaje SMS y de WhatsApp a un teléfono móvil. El alcance logrado en la transmisión wifi en la red fue 47 metros con línea de vista.//This paper presents the construction of a prototype of a door and window monitoring system through an IoT platform. The objective was to design a system that reports to a server in the cloud the change of state, open or closed, of three doors and two windows of the equipment room of the data center. The changes of state are registered by the server and by means of a user interface the status of doors and windows is displayed online. The architecture of the system is based on a wireless sensor network integrated by a central node and five monitoring nodes. The monitoring nodes consist of a PyBoard card, two digital Hall effect sensors and a WiFi wireless interface. When detecting a change of state in doors and windows, the monitoring nodes notify it to the central node, and this transmits it to the server through a WiFi access point. When a door or window remains open for more than a configurable period of time, an SMS and WhatsApp message is sent to a mobile phone. The reach achieved in the WiFi transmission on the network was 47 meters with line of sight