Formulación del M.E.C. en elasticidad tridimensional mediante macroelementos y colocación no nodal

Se presenta en este trabajo un nuevo enfoque del Método de los Elementos de Contorno en Elasticidad tridimensional basado en una aproximación global de la geometría en el interior de macroelementos junto con una estrategia de colocación no nodal, que permite obviar el tema de los nodos esquina, elimina la necesidad de evaluación del término libre que ahora es fijo y de valor 0.5 Sij y simplifica el tratamiento de subregiones con las ventajas que ello supone desde el punto de vista computacional.Peer Reviewe

Repercusiones organizativas en la Ley de Prevención de Riesgos Laborales: Una aproximación explorativa

La. aplicación efectiva de la Ley 3.1/1995 de 8 de noviembre, de Prevención de riesgos Laborales y sus respectivos reglamentos, están provocando cambios en las empresas que van más allá de] propio campo de la salud y seguridad laborales, y que se están haciendo notar en el ámbito organizativo, y concreto en aspectos tales como la motivación del personal, la cultura organizacional, la productividad, los costes y la propia formación y actitudes a todos los niveles. A través de las opiniones de expertos y res -ponsables directamente implicados en esta área, hemos pretendido plantear una serie de hipótesis que marquen hacia donde se dirigen las preocupaciones y los posibles cambios antes señalados. La actual legislación en materia de seguridad laboral está exigiendo a las empresas profundas reformas en las medidas y acciones que han de tomar en esta materia. El presente artículo recoge la opinión de los principales agentes implicados: empresarios y sindicatos. Cómo perciben los posibles cambios e incidencias que la aplicación de la ley puede tener en distintos aspectos de la organización, de personal, etc..

Repercusiones organizativas en la Ley de Prevención de Riesgos Laborales : una aproximación explorativa

La aplicación efectiva de la Ley 3.1/1995 de 8 de noviembre, de Prevención de riesgos Laborales y sus respectivos reglamentos, están provocando cambios en las empresas que van más allá del propio campo de la salud y seguridad laborales, y que se están haciendo notar en el ámbito organizativo, y concreto en aspectos tales como la motivación del personal, la cultura organizacional, la productividad, los costes y la propia formación y actitudes a todos los niveles. A través de las opiniones de expertos y responsables directamente implicados en esta área, hemos pretendido plantear una serie de hipótesis que marquen hacia donde se dirigen las preocupaciones y los posibles cambios antes señalados. La actual legislación en materia de seguridad laboral está exigiendo a las empresas profundas reformas en las medidas y acciones que han de tomar en esta materia. El presente artículo recoge la opinión de los principales agentes implicados: empresarios y sindicatos. Cómo perciben los posibles cambios e incidencias que la aplicación de la ley puede tener en distintos aspectos de la organización, de personal, etc...______________________________________ The current legislation as regards labor security is demanding the companies deep reformations in the measures and actions that they are supposed to take in this matter. The present article picks up the opinion of the main implied agents: managers and unions. How they perceive the possible changes and incidences that the application of the law could have in different aspects of the organization, of personal, etc

Formulación del M.E.C. en elasticidad tridimensional mediante macroelementos y colocación no nodal

Se presenta en este trabajo un nuevo enfoque del Método de los Elementos de Contorno en Elasticidad tridimensional basado en una aproximación global de la geometría en el interior de macroelementos junto con una estrategia de colocación no nodal, que permite obviar el tema de los nodos esquina, elimina la necesidad de evaluación del término libre que ahora es fijo y de valor 0.5 Sij y simplifica el tratamiento de subregiones con las ventajas que ello supone desde el punto de vista computacional.Peer Reviewe

Migrations internationales aux Canaries

Only seldom do geographers experience the possibility of effectively providing guidelines for policy makers, of bridging the gap that usually separates academia from praxis. The agreement signed between the Parliament of the Canary Islands and the Islands’ two universities, setting up a group of experts and a parliamentary subcommittee in order to provide guidance for immigration policy-making, has been a landmark in the case of both academic institutions. The agreement has provided researchers with the opportunity to put an applied knowledge of widespread social impact into practice. Likewise, Members of Parliament have been offered the chance to base their policy-making on sound social and scientific foundations. The present paper analyses this initiative and the work undertaken from a geographical perspective, based on the authors’ conviction that it might help other similar institutions to bring science and social commitment closer together, especially within the context of international migrations.En pocas ocasiones se brinda a los geógrafos la posibilidad de que sus investigaciones orienten las actuaciones políticas, conjugando academia y praxis. Por ello, la firma de un convenio entre el Parlamento de Canarias y las dos universidades del archipiélago, creando un grupo de expertos y una subcomisión parlamentaria para orientar las actuaciones políticas en la gestión de la inmigración, representó un hito en la acción de dichas instituciones. Para los investigadores, la oportunidad de poner en práctica una disciplina de profunda repercusión social. Para los parlamentarios, la posibilidad de fundamentar sus actuaciones legislativas en un basamento científica y socialmente acreditado. El análisis de esta iniciativa y del trabajo efectuado desde la perspectiva geográfica constituye el objeto de este artículo, planteado desde el convencimiento de que puede guiar otras iniciativas semejantes en las que ciencia y compromiso social estrechen sus vínculos, especialmente en el ámbito de las migraciones internacionales.Il est rarement offert aux géographes la possibilité d’orienter les actions politiques par leurs recherches en conjuguant académie et praxis. Or, la signature d’une convention entre le Parlement des Canaries et les deux universités de l’archipel, entraînant la création d’un groupe d’experts et d’une sous-commission parlementaire pour orienter les interventions politiques dans la gestion de l’immigration, a marqué un tournant dans l’action de ces institutions. Les chercheurs ont eu l’occasion de mettre en pratique une discipline d’une profonde répercussion sociale, et les parlementaires la possibilité d’asseoir leurs décisions législatives sur une base scientifiquement et socialement reconnue. Le but de cet article est d’analyser cette initiative et le travail effectué du point de vue géographique, dans la certitude qu’il peut servir de guide à d’autres initiatives semblables dans lesquelles la science et l’engagement social puissent resserrer leurs liens, en particulier dans le domaine des migrations internationales

In Situ Thermal-Stage Fitted-STEM Characterization of Spherical-Shaped Co/MoS2_{2} Nanoparticles for Conversion of Heavy Crude Oils

We report the thermal stability of spherically shaped cobalt-promoted molybdenum disulfide (Co/MoS$_{2}$) nano-catalysts from in-situ heating under electron irradiation in the scanning transmission electron microscope (STEM) from room temperature to 550 °C ± 50 °C with aid of Fusion® holder (Protochip©, Inc.). The catalytic nanoparticles were synthesized via a hydrothermal method using sodium molybdate (Na$_{2}$MoO$_{4}$·2H$_{2}$O) with thioacetamide (CH$_{3}$CSNH$_{2}$) and cobalt chloride (CoCl$_{2}$) as promoter agent. The results indicate that the layered molybdenum disulfide structure with interplanar distance of ~0.62 nm remains stable even at temperatures of 550 °C, as observed in STEM mode. Subsequently, the samples were subjected to catalytic tests in a Robinson Mahoney Reactor using 30 g of Heavy Crude Oil (AGT-72) from the golden lane (Mexico’s east coast) at 50 atm using (ultrahigh purity) UHP hydrogen under 1000 rpm stirring at 350 °C for 8 h. It was found that there is no damage on the laminar stacking of Co/MoS2 with temperature, with interlayer spacing remaining at 0.62 nm; these sulfided catalytic materials led to aromatics rise of 22.65% and diminution of asphaltenes and resins by 15.87 and 3.53%, respectively

Modelo de competencias para el campo conceptual aditivo de las magnitudes discretas relativas

In this work we propose a competence model that allows us to organize the additive conceptual field for relative discrete magnitudes from the perspective of problem solving. We start off from Piaget's concrete operations subperiod where logical and infralogical groupings, arithmetical group Z and measuring are involved. The organizing features of the model will be the epistemological, phenomenological and cognitive elements associated with this field. This organizational proposal constitutes a competence model for the additive conceptual field which integrates those elements and relations given in this field, and which leads to a new classification of different situations and problems associated with it, as well as incorporating and explaining other research, especially that research made in the field of whole numbers by Carpenter and Moser (1983) and others, and the categories put forward by Vergnaud (1982). Furthermore, our proposal facilitates relations with a possible performance model

Smart Footwear Insole for Recognition of Foot Pronation and Supination Using Neural Networks

Abnormal foot postures during gait are common sources of pain and pathologies of the lower limbs. Measurements of foot plantar pressures in both dynamic and static conditions can detect these abnormal foot postures and prevent possible pathologies. In this work, a plantar pressure measurement system is developed to identify areas with higher or lower pressure load. This system is composed of an embedded system placed in the insole and a user application. The instrumented insole consists of a low-power microcontroller, seven pressure sensors and a low-energy bluetooth module. The user application receives and shows the insole pressure information in real-time and, finally, provides information about the foot posture. In order to identify the different pressure states and obtain the final information of the study with greater accuracy, a Deep Learning neural network system has been integrated into the user application. The neural network can be trained using a stored dataset in order to obtain the classification results in real-time. Results prove that this system provides an accuracy over 90% using a training dataset of 3000+ steps from 6 different users.Ministerio de Economía y Competitividad TEC2016-77785-

Solar thermal hot water system in hospitals: Robust design methodology considering uncertainties

The energy yield of solar thermal installations is influenced by local climatic conditions, heating demand, and the efficiency of the system. These factors are affected by uncertainties arising from natural variations and a lack of knowledge. Designers typically address these uncertainties by oversizing the collector area. However, this practice usually leads to high costs, low efficiency, and short service lifetimes of the system. This paper proposes a robust sizing methodology for the solar thermal system used for service hot water preparation in a case-study hospital with a daily average hot water consumption of 8.69 m3. This novel approach incorporates uncertainties through probabilistic simulations, assessing the system’s reliability in achieving a 70% solar fraction design goal. The simulations reveal a mere 22% confidence in the initial deterministic design concerning the solar target and emphasize the importance of thermal insulation, temperature control, and collector cleaning as key factors to reduce performance variability. Although the final revised design outcome requires a 15% increase in the collector area compared to the initial scenario and stricter specifications for control components, pipe insulation, and valve maintenance, it achieves a 90% reliability. In addition, annual carbon emissions and levelized costs of hot water production can be reduced by 18% and 13%, respectively.Funding for open access charge: Universidad de Málaga / CBUA. The authors acknowledge the Universidad de Málaga and ‘‘Programa Operativo FEDER Andalucía 2014-2020’’ for the financial support of the contract UMA18-FEDERJA-247. The authors also gratefully acknowledge Mr. Pedro Quintero Jiménez, head of the energy services at Hospital Comarcal de la Axarquía, for providing data and helpful information concerning the system analyzed

Detailed and simplified models of a terminal unit that combines an UFAD system with a floor cooling

This paper analyses the thermal behaviour of an underfloor air distribution system (UFAD) combined with a floor cooling, focusing on the thermal decay (TD). Two new models were implemented: a detailed model based on the convective heat transfer coefficient inside the plenum, and a simplified model based on the bypass factor. To validate the models we performed three experiments. Both, detailed and simplified models, reproduce well the measured TD. The maximum relative errors between the predicted and measured TD were 8.4% (transient state) and 1.3% (steady state). Although differences were higher at transient regimen, the terminal unit is designed to operate with smooth changes of the boundary conditions. As the error obtained by detailed and simplified models was near identical, the model based on the bypass factor is recommended because of its simplicity. A sensitivity analysis was performed. We evaluated: (1) the TD as a function of the supply air temperature and air flow rate, (2) the cooling capacity of the floor, and (3) the cooling capacity of the ventilation air. The paper concludes with a nomographic design chart that brings together all the features of the terminal unit, allowing a quick selection of the operating parameters