8,036 research outputs found
Modélisation en flux d’énergie d’une batterie Li-Ion en vue d’une optimisation technico-économique d’un micro-réseau intelligent
Dans cet article, un modèle de type flux d’énergie pour une batterie Li-Ion est présenté. Le modèle décrit permet de simuler une batterie Li-Ion d’un point de vue systémique. Le but de la modélisation présentée est de proposer une solution, avec un coût de calcul réduit, au problème de simulation avec des grands horizons d’étude (plusieurs années). L’approche proposée est basée sur l’élaboration de cartographies à partir du modèle dynamique de la batterie Li-Ion. Cette modélisation inclut aussi un modèle macroscopique du vieillissement de la cellule, en considérant la dégradation de la capacité de la batterie au cours du temps. Le modèle global présenté permet d’obtenir un bon compromis entre la précision dans l’estimation de l’état de charge de la batterie et la vitesse de calcul de la simulation. L’originalité de l’approche consiste à calculer d’une façon précise et en un temps très réduit l’énergie effectivement chargée ou déchargée de la batterie
Prevención de accidentes e incidentes más frecuentes en la operación de maquinaria pesada mediante el uso de simuladores de entrenamiento
La fundamentación de este proyecto de tesis se encuentra orientado a la
prevención de accidentes e incidentes más recurrentes en la operación de
maquinaria pesada haciendo uso de simuladores de preentrenamiento.
Siendo la finalidad de estos últimos, formar operarios competitivos y
comprometidos con la preservación de la vida, los recursos de la empresa y el
medio ambiente, asà mismo la seguridad de los conductores y de la maquinaria
que operan.
Se procedió a capacitar teóricamente al estudiante respecto a las normativas de
seguridad, luego se hizo uso de simuladores Simlog con los cuales se instruyó a
una muestra de estudiantes por conveniencia, obteniéndose como resultados las
etapas inicial con 90% de incidentes, en la etapa intermedia las incidencias
fueron del 40% y en la etapa final estas no superaron el 10%.en el uso del
simulador. Por otro lado, se determinaron los costos mÃnimos al no utilizar
simulador que ascienden a 3000 soles.
Asà mismo, se capacitó al estudiante, en el entrenamiento con maquinas reales
en un periodo de 20 horas, obteniéndose los resultados de cero accidentes e
incidentesThe foundation of this thesis project is oriented to the prevention of
accidents and more recurring incidents in the operation of heavy
machinery using pre-training simulators.
Being the purpose of the latter, to train competitive operators and
committed to the preservation of life, company resources and the
environment, as well as the safety of drivers and the machinery they
operate.
The student was theoretically trained regarding safety regulations, then
Simlog simulators were used with which a sample of students was
instructed for convenience, obtaining as results the initial stages with 90%
of incidents, in the intermediate stage the incidences were 40% and in the
final stage these did not exceed 10% in the use of the simulator. On the
other hand, the minimum costs were determined by not using a simulator
that amounted to 3000 soles.
Likewise, the student was trained in training with real machines in a period
of 20 hours, obtaining the results of zero accidents and incidentsTesi
Protocolo para monitorear la gobernabilidad del agua con base en indica-dores para cuencas rurales
The use of quality indicators guarantees the accurate monitoring of sustainability processes around the world. This work proposes a protocol to detail the indicators that make up the rural basin management index (GWI) in order to assess the degree of water management in a predominantly rural basin or region. The methodology contemplates the development of indicators to evaluate performance and its monitoring over time as the basis for planning. This research is based on the in situ evaluation of four municipalities within the department of Boyacá, Colombia, where there is a lack of a culture regarding the long-term planning and management of water and environmental resources. Water availability is the most sensitive factor in this context. This study raises the need for the use of monitoring systems in sustainability processes at the level of rural basins, as a result of the findings of four study cases, where processes with a low level of sustainability were evidenced.Peer ReviewedPostprint (published version
Techno-economical optimization of wind power production including lithium and/or hydrogen sizing in the context of the day ahead market in island grids
In this article an optimal storage sizing based on technical and economical modeling is presented. A focus is made on wind power producers participating in day-ahead markets for island networks and energy storage using Li-Ion and H2/O2 batteries. The modeling approach is based on power flow models and detailed optimization-oriented techniques. An importance is given to the storage device ageing effects on the overall hybrid system levelized cost of the energy. The results are presented for the special case of renewable power integration in the French islands networks. The analysis obtained after the results shows the importance of this type of modeling tool for decision making during the initial conceptual design level
Effect of thermophosphate on the growth and production of potatoes (Solanum tuberosum L.)
El cultivo de papa es uno de los más representativos de los Andes colombianos. El cultivo tiene altos costos de producción, entre los cuales, la fertilización representa un 36% del total. Los avances tecnológicos en nutrición vegetal han permitido el desarrollo de nuevos compuestos, que generan una mayor asimilación y disponibilidad de los elementos nutritivos, durante los periodos productivos. Dentro de las diferentes fuentes de fósforo empleadas en Colombia, está como alternativa, el termofosfato o fosfato térmico. Por esto, el objetivo del presente trabajo fue evaluar la aplicación del termofosfato en el cultivo de papa variedad ‘Superior’, en condiciones de campo, en el municipio de Villa Pinzón, Cundinamarca. Se empleó un diseño completamente al azar, con 4 tratamientos, que correspondieron a diferentes porcentajes de fosfato térmico 100% fosfato diamónico (DAP) (manejo convencional); 80% DAP, 20% fosfato térmico (FT); 40% DAP, 60% FT y 20% DAP, 80% FT, (0, 300, 600 y 900kg ha-1), con tres réplicas, para un total de 12 unidades experimentales. Las variables evaluadas fueron pesos fresco y seco, de parte área y raÃz, concentración de fósforo en tejido y rendimiento por calidades y total. Se observó que la aplicación de termofosfato en diferentes concentraciones generó un efecto positivo con diferencias estadÃsticas (P≤0,05), en todas las variables evaluadas. El tratamiento de 600kg ha-1 de termofosfato, se muestra como una alternativa para el aporte de fósforo dentro de los planes de fertilización, en busca de una mejor respuesta fisiológica y productiva del cultivo de papa.Potato cultivation is one of the most representative activities of the Colombian Andes. The crop has high production costs, among which fertilization represents 36% of the total Technological advances in plant nutrition have allowed the development of new compounds that generate greater assimilation and availability of nutritional elements during productive periods. Within the different phosphorus sources available in Colombia, thermophosphate exists as an alternative. For this reason, the objective of this research was to evaluate the application of thermophosphate in the potato crop, Superior ’variety, under field conditions in the municipality of Villa Pinzón-Cundinamarca. A completely randomized design was used with 4 treatments that corresponded to different percentages of thermal phosphate: 100% diammonium phosphate (DAP) (conventional management); 80% DAP, 20% thermal phosphate (TF); 40% DAP, 60% TF and 20% DAP, 80% TF (0, 300, 600 y 900kg ha-1), with three replicas for a total of 12 experimental units. The variables evaluated were fresh and dry weights of areal and root part, phosphorus concentration in tissue and yield by qualities and the total. It was observed that the application of thermophosphate at different concentrations generated a positive effect, statistically different (P≤0.05) in all the variables evaluated. Thermophosphate, at 600kg ha-1 was found to be an alternative for the contribution of phosphorus within the fertilization plans, in search of a better physiological and productive response of the potato crop.Incluye referencias bibliográfica
Reduced proliferation of endothelial colony-forming cells in unprovoked venous thromboembolic disease as a consequence of endothelial dysfunction
Background
Venous thromboembolic disease (VTD) is a public health problem. We recently reported that endothelial colony-forming cells (ECFCs) derived from endothelial cells (EC) (ECFC-ECs) from patients with VTD have a dysfunctional state. For this study, we proposed that a dysfunctional status of these cells generates a reduction of its proliferative ability, which is also associated with senescence and reactive oxygen species (ROS).
Methods and results
Human mononuclear cells (MNCs) were obtained from peripheral blood from 40 healthy human volunteers (controls) and 50 patients with VTD matched by age (20−50 years) and sex to obtain ECFCs. We assayed their proliferative ability with plasma of patients and controls and supernatants of cultures from ECFC-ECs, senescence-associated β-galactosidase (SA-β-gal), ROS, and expression of ephrin-B2/Eph-B4 receptor. Compared with cells from controls, cells from VTD patients showed an 8-fold increase of ECFCs that emerged 1 week earlier, reduced proliferation at long term (39%) and, in passages 4 and 10, a highly senescent rate (30±1.05% vs. 91.3±15.07%, respectively) with an increase of ROS and impaired expression of ephrin-B2/Eph-4 genes. Proliferation potential of cells from VTD patients was reduced in endothelial medium [1.4±0.22 doubling population (DP)], control plasma (1.18±0.31 DP), or plasma from VTD patients (1.65±0.27 DP).
Conclusions
As compared with controls, ECFC-ECs from individuals with VTD have higher oxidative stress, proliferation stress, cellular senescence, and low proliferative potential. These findings suggest that patients with a history of VTD are ECFC-ECs dysfunctional that could be associated to permanent risk for new thrombotic events
Toward a new data standard for combined marine biological and environmental datasets - expanding OBIS beyond species occurrences
The Ocean Biogeographic Information System (OBIS) is the world's most comprehensive online, open-access database of marine species distributions. OBIS grows with millions of new species observations every year. Contributions come from a network of hundreds of institutions, projects and individuals with common goals: to build a scientific knowledge base that is open to the public for scientific discovery and exploration and to detect trends and changes that inform society as essential elements in conservation management and sustainable development. Until now, OBIS has focused solely on the collection of biogeographic data (the presence of marine species in space and time) and operated with optimized data flows, quality control procedures and data standards specifically targeted to these data. Based on requirements from the growing OBIS community to manage datasets that combine biological, physical and chemical measurements, the OBIS-ENV-DATA pilot project was launched to develop a proposed standard and guidelines to make sure these combined datasets can stay together and are not, as is often the case, split and sent to different repositories. The proposal in this paper allows for the management of sampling methodology, animal tracking and telemetry data, biological measurements (e.g., body length, percent live cover, ...) as well as environmental measurements such as nutrient concentrations, sediment characteristics or other abiotic parameters measured during sampling to characterize the environment from which biogeographic data was collected. The recommended practice builds on the Darwin Core Archive (DwC-A) standard and on practices adopted by the Global Biodiversity Information Facility (GBIF). It consists of a DwC Event Core in combination with a DwC Occurrence Extension and a proposed enhancement to the DwC MeasurementOrFact Extension. This new structure enables the linkage of measurements or facts - quantitative and qualitative properties - to both sampling events and species occurrences, and includes additional fields for property standardization. We also embrace the use of the new parentEventID DwC term, which enables the creation of a sampling event hierarchy. We believe that the adoption of this recommended practice as a new data standard for managing and sharing biological and associated environmental datasets by IODE and the wider international scientific community would be key to improving the effectiveness of the knowledge base, and will enhance integration and management of critical data needed to understand ecological and biological processes in the ocean, and on land.Fil: De Pooter, Daphnis. Flanders Marine Institute; BélgicaFil: Appeltans, Ward. UNESCO-IOC; BélgicaFil: Bailly, Nicolas. Hellenic Centre for Marine Research, MedOBIS; GreciaFil: Bristol, Sky. United States Geological Survey; Estados UnidosFil: Deneudt, Klaas. Flanders Marine Institute; BélgicaFil: Eliezer, Menashè. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Fujioka, Ei. University Of Duke. Nicholas School Of Environment. Duke Marine Lab; Estados UnidosFil: Giorgetti, Alessandra. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Goldstein, Philip. University of Colorado Museum of Natural History, OBIS; Estados UnidosFil: Lewis, Mirtha Noemi. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Lipizer, Marina. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Mackay, Kevin. National Institute of Water and Atmospheric Research; Nueva ZelandaFil: Marin, Maria Rosa. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Moncoiffé, Gwenaëlle. British Oceanographic Data Center; Reino UnidoFil: Nikolopoulou, Stamatina. Hellenic Centre for Marine Research, MedOBIS; GreciaFil: Provoost, Pieter. UNESCO-IOC; BélgicaFil: Rauch, Shannon. Woods Hole Oceanographic Institution; Estados UnidosFil: Roubicek, Andres. CSIRO Oceans and Atmosphere; AustraliaFil: Torres, Carlos. Universidad Autonoma de Baja California Sur; MéxicoFil: van de Putte, Anton. Royal Belgian Institute for Natural Sciences; BélgicaFil: Vandepitte, Leen. Flanders Marine Institute; BélgicaFil: Vanhoorne, Bart. Flanders Marine Institute; BélgicaFil: Vinci, Mateo. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; ItaliaFil: Wambiji, Nina. Kenya Marine and Fisheries Research Institute; KeniaFil: Watts, David. CSIRO Oceans and Atmosphere; AustraliaFil: Klein Salas, Eduardo. Universidad Simon Bolivar; VenezuelaFil: Hernandez, Francisco. Flanders Marine Institute; Bélgic
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