167 research outputs found
Enhanced Demand and Capacity Balancing based on Alternative Trajectory Options and Traffic Volume Hotspot Detection
Nowadays, regulations in Europe are applied at traffic volume (TV) level consisting in a reference location, i.e. a sector or an airport, and in some traffic flows, which act as directional traffic filters. This paper presents an enhanced demand and capacity balance (EDCB) formulation based on constrained capacities at traffic volume level. In addition, this approach considers alternative trajectories in order to capture the user driven preferences under the trajectory based operations scope. In fact, these alternative trajectories are assumed to be generated by the airspace users for those flights that cross regulated traffic volumes, where the demand is above the capacity. For every regulated trajectory the network manager requests two additional alternative trajectories to the airspace users, one for avoiding the regulated traffic volumes laterally and another for avoiding it vertically. This paper considers that the network manager allows more flexibility for the new alternative trajectories by removing restrictions in the Route Availability Document (RAD). All the regulated trajectories (and their alternatives) are considered together by the EDCB model in order to perform a centralised optimisation minimising the the cost deviation with respect to the initial traffic situation, considering fuel consumption, route charges and cost of delay. The EDCB model, based on Mixed-Integer Linear Programming (MILP), manages to balance the network applying ground delay, using alternative trajectories or both. A full day scenario over the ECAC area is simulated. The regulated traffic volumes are identified using historical data (based on 28th July of 2016) and the results show that the EDCB could reduce the minutes of delay by 70%. The cost of the regulations is reduced by 11.7%, due to the reduction of the delay, but also because of the savings in terms of fuel and route charges derived from alternative trajectories
Color de aceites de oliva virgen extra enriquecidos con carotenoides procedentes de microalgas: influencia de la exposición a la radiación ultravioleta y al calentamiento
A carotenoid-rich extract containing 2.5 mg/mL of lutein and 3.3 mg/mL of β-carotene from the microalga Scenedesmus
almeriensis was added to ten extra virgin olive oils from four Spanish cultivars with differing degrees of ripeness, obtaining carotenoid
enriched oils with lutein and β-carotene concentrations of 0.082 and 0.11 mg/mL, respectively. Extra virgin olive oils enriched with carotenoids
from microalgae were studied by analyzing the effect on color of three different treatments: ultraviolet exposure, microwave
heating and immersion bath heating. The methodology was designed to simulate, in controlled laboratory conditions, the effects of household
treatments. Spectrophotometric color measurements were then performed to monitor color changes in the enriched and non-enriched
extra virgin olive oil samples. Enriched oils are much more chromatic, darker and redder than natural oils. After 55 days UV irradiation,
40 min microwave heating, and 72 hours thermostatic heating, the average color differences for natural/enriched extra virgin olive oils
were 98/117, 15/9 and 57/28 CIELAB units, respectively. In general, increasing temperature and ultraviolet exposure produced higher
CIELAB color differences in the non-enriched samples. The addition of microalga extracts to extra virgin olive oils was found to induce
some color stability and may constitute a future way of increasing the daily intake of beneficial bioactive compounds such as carotenoids.Añadimos un extracto rico en carotenoides, que contiene 2,5 mg/mL de luteína y
3,3 mg/mL de β-caroteno, procedente de la microalga Scenedesmus almeriensis, a diez aceites de oliva virgen extra de cuatro variedades
con diferentes grados de maduración, obteniéndose aceites enriquecidos en carotenoides con concentraciones de luteína y β-caroteno
de 0,082 y 0,11 mg/mL respectivamente. Se han estudiado aceites de oliva virgen extra enriquecidos con carotenoides procedentes de
microalgas, estudiando el efecto producido sobre el color de los mismos como consecuencia de irradiación ultravioleta, calentamiento
en microondas y en baño termostático, reproduciendo en el laboratorio los efectos de los tratamientos domésticos. Se ha determinado el
color para monitorizar los cambios de las muestras control y enriquecidas de los diferentes aceites. Los aceites enriquecidos son mucho
más cromáticos, oscuros y rojizos que los naturales. Tras 55 días de irradiación UV, 40 minutos de calentamiento por microondas y 72
horas de calentamiento termostático, las diferencias medias de color para los aceites de oliva virgen extra naturales/enriquecidos fueron
de 98/117, 15/9 y 57/28 unidades CIELAB, respectivamente. En término generales, el incremento en la temperatura y la exposición a la
radiación ultravioleta produce diferencias de color más grandes en las muestras no enriquecidas. El enriquecimiento de los aceites virgen
extra con extractos procedentes de microalgas, induce estabilidad en el color y puede constituir una vía para incrementar la ingesta diaria
de compuestos bioactivos beneficiosos como son los carotenoides.University of JaenCastillo de Canena Olive Juice companyMinistry of Science and Innovation of the National Government of Spain PID2019107816GB-I00 / AEI / 10.13039/50110001103
Color de aceites de oliva virgen extra enriquecidos con carotenoides procedentes de microalgas: influencia de la exposición a la radiación ultravioleta y al calentamiento
A carotenoid-rich extract containing 2.5 mg/mL of lutein and 3.3 mg/mL of β-carotene from the microalga Scenedesmus almeriensis was added to ten extra virgin olive oils from four Spanish cultivars with differing degrees of ripeness, obtaining carotenoid enriched oils with lutein and β-carotene concentrations of 0.082 and 0.11 mg/mL, respectively. Extra virgin olive oils enriched with carotenoids from microalgae were studied by analyzing the effect on color of three different treatments: ultraviolet exposure, microwave heating and immersion bath heating. The methodology was designed to simulate, in controlled laboratory conditions, the effects of household treatments. Spectrophotometric color measurements were then performed to monitor color changes in the enriched and non-enriched extra virgin olive oil samples. Enriched oils are much more chromatic, darker and redder than natural oils. After 55 days UV irradiation, 40 min microwave heating, and 72 hours thermostatic heating, the average color differences for natural/enriched extra virgin olive oils were 98/117, 15/9 and 57/28 CIELAB units, respectively. In general, increasing temperature and ultraviolet exposure produced higher CIELAB color differences in the non-enriched samples. The addition of microalga extracts to extra virgin olive oils was found to induce some color stability and may constitute a future way of increasing the daily intake of beneficial bioactive compounds such as carotenoids.Añadimos un extracto rico en carotenoides, que contiene 2,5 mg/mL de luteína y 3,3 mg/mL de β-caroteno, procedente de la microalga Scenedesmus almeriensis, a diez aceites de oliva virgen extra de cuatro variedades con diferentes grados de maduración, obteniéndose aceites enriquecidos en carotenoides con concentraciones de luteína y β-caroteno de 0,082 y 0,11 mg/mL respectivamente. Se han estudiado aceites de oliva virgen extra enriquecidos con carotenoides procedentes de microalgas, estudiando el efecto producido sobre el color de los mismos como consecuencia de irradiación ultravioleta, calentamiento en microondas y en baño termostático, reproduciendo en el laboratorio los efectos de los tratamientos domésticos. Se ha determinado el color para monitorizar los cambios de las muestras control y enriquecidas de los diferentes aceites. Los aceites enriquecidos son mucho más cromáticos, oscuros y rojizos que los naturales. Tras 55 días de irradiación UV, 40 minutos de calentamiento por microondas y 72 horas de calentamiento termostático, las diferencias medias de color para los aceites de oliva virgen extra naturales/enriquecidos fueron de 98/117, 15/9 y 57/28 unidades CIELAB, respectivamente. En término generales, el incremento en la temperatura y la exposición a la radiación ultravioleta produce diferencias de color más grandes en las muestras no enriquecidas. El enriquecimiento de los aceites virgen extra con extractos procedentes de microalgas, induce estabilidad en el color y puede constituir una vía para incrementar la ingesta diaria de compuestos bioactivos beneficiosos como son los carotenoides
Detecció d'errors en l'aprenentatge dels triangles
Curs 2012-2013Aquest treball es basa en realitzar un estudi per tal d'identificar quins errors
matemàtics cometen un grup d'alumnes de primer curs d'educació primària, en relació
a la geometria. Concretament, aquest estudi és per identificar, mitjançant una prova,
quines dificultats presenten els nens en relació als triangles. A partir dels errors que
hagin sorgit, es dissenyarà la intervenció per tal d'intentar-los solucionar. Finalment,
s'analitzarà si amb el treball realitzat els alumnes milloren els errors. En aquest treball
s'ha utilitzat el mètode Concret-Representació-Abstracte de Bruner i les propostes que
proposen certs autors (Bamberger, Schultz-Ferrell, ...) per ajudar a superar aquests
errors. Realitzant aquest estudi s'ha pogut observar que els alumnes tenen la imatge
d'un triangle prototípic. Això fa que cometin errors quan se'ls presenten altres triangles.This work is based on a study to identify mathematical errors committed by a group of
students in their first year of primary education in relation to geometry. Specifically, this
study is to identify, through a test, the difficulties children have in relation to triangles.
From the errors that have arisen, the intervention is designed to try to solve them.
Finally, we analyse whether the students, after the intervention, don't make similar
errors. In this paper we have used the Bruner's method Concrete-Representational-
Abstract and proposals that suggest some authors (Bamberger, Schultz-Ferrell, ...) to
help overcome these errors. In this study it was observed that the students have the
prototypical image of a triangle. Children make errors when showed other triangles
Biocatalytic quantification of alpha-glucan in marine particulate organic matter
Marine algae drive the marine carbon cycle, converting carbon dioxide into organic material. A major component of this produced biomass is a variety of glycans. Marine alpha-glucans include a range of storage glycans from red and green algae, bacteria, fungi, and animals. Although these compounds are likely to account for a high amount of the carbon stored in the oceans they have not been quantified in marine samples so far. Here we present a method to extract and quantify alpha-glucans (and compare it with the beta-glucan laminarin) in particulate organic matter from algal cultures and environmental samples using sequential physicochemical extraction and enzymes as alpha-glucan-specific probes. This enzymatic assay is more specific and less susceptible to side reactions than chemical hydrolysis. Using HPAEC-PAD to detect the hydrolysis products allows for a glycan quantification in particulate marine samples down to a concentration of approximate to 2 mu g/L. We measured glucans in three cultured microalgae as well as in marine particulate organic matter from the North Sea and western North Atlantic Ocean. While the beta-glucan laminarin from diatoms and brown algae is an essential component of marine carbon turnover, our results further indicate the significant contribution of starch-like alpha-glucans to marine particulate organic matter. Henceforth, the combination of glycan-linkage-specific enzymes and chromatographic hydrolysis product detection can provide a powerful tool in the exploration of marine glycans and their role in the global carbon cycle
Measuring color differences in gonioapparent materials used in the automotive industry
This paper illustrates how to design a visual experiment to measure color differences in gonioapparent materials and how to assess the merits of different advanced color-difference formulas trying to predict the results of such experiment. Successful color-difference formulas are necessary for industrial quality control and artificial color-vision applications. A color- difference formula must be accurate under a wide variety of experimental conditions including the use of challenging materials like, for example, gonioapparent samples. Improving the experimental design in a previous paper [Melgosaet al., Optics Express 22, 3458-3467 (2014)], we have tested 11 advanced color-difference formulas from visual assessments performed by a panel of 11 observers with normal colorvision using a set of 56 nearly achromatic colorpairs of automotive gonioapparent samples. Best predictions of our experimental results were found for the AUDI2000 color-difference formula, followed by color-difference formulas based on the color appearance model CIECAM02. Parameters in the original weighting function for lightness in the AUDI2000 formula were optimized obtaining small improvements. However, a power function from results provided by the AUDI2000 formula considerably improved results, producing values close to the inter-observer variability in our visual experiment. Additional research is required to obtain a modified AUDI2000 color-difference formula significantly better than the current one.This research was supported by the Ministry of Economy and Competitiveness of Spain, research
projects FIS2013-40661-P and DPI2011-30090-C02, with European Research Development Fund
(ERDF), as well as by the National Science Foundation of China (grant number 61178053)
Soft Tissue Behavior During Limb Lengthening: An Experimental Study in Lambs
The effect of femoral elongation on skeletal muscle, nerves, and vessels was studied. Three groups of five lambs were used. After the intervention, the animals were killed at 2, 3, and 4 months. A left femoral elongation of 6 cm was practiced on all of them by means of callotasis, with a distraction rate of 0.5 mm every 12 hours. The femoral elongation process was evaluated by monthly x-ray films. The nucleic acid and protein levels in the muscular tissue were quantified at the level of the elongation focus and in the control extremity. The motor conduction velocity of the sciatic nerve was measured in both posterior limbs before the intervention and immediately before the lambs were killed. The arterial blood flow of both subsequent extremities was measured at the moment of death. A histological study of quadriceps muscle, sciatic nerves, artery, and subsequent femoral vein were examined histologically at the level of the elongation focus of both extremities. After elongation, no significant differences were observed in the muscle protein and nucleic acid levels with respect to the control extremity. No significant changes of the nerve conduction velocity were observed in any animal among the different groups. The arterial blood flow of the elongated extremity showed a progressive increase, reaching its maximum value 1 month after the distraction had terminated, with subsequent normalization. This increase of the blood flow was also observed in the control extremity, suggesting a possible systemic effect. The histological study revealed a comparative thickening of the endomysium and perimysium in the elongated muscle tissue, present at the end of the distraction and which was later normalized. No histological changes of the nerve stems undergoing distraction were observed either. During elongation, the arteries showed minimal histological changes. On the other hand, the veins showed areas of endothelial damage accompanied by thrombosis phenomena, especially at the end of the distraction period. The vascular morphology presented progressive normalization after the distraction phase
All Effects of Psychophysical Variables on Color Attributes: A Classification System
This paper reports the research and structuring of a classification system for the effects of psychophysical variables on the color attributes. A basic role of color science is to psychophysically specify color appearance. An early stage is to specify the effects of the psychophysical variables (as singles, pairs, etc) on the color attributes (as singles, pairs, etc), for example to model color appearance. Current data on effects are often scarce or conflicting. Few effects are well understood, and the practice of naming effects after their discoverer(s) is inadequate and can be confusing. The number and types of possible effects have never been systematically analyzed and categorized. We propose a simple and rigorous system of classification including nomenclature. The total range of effects is computed from the possible combinations of three psychophysical variables (luminance, dominant wavelength, purity) and six color attributes (lightness, brightness, hue, chroma, colorfulness, saturation) in all modes of appearance. Omitting those effects that are normally impossible to perceive at any one time (such as four- or five-dimensional colors), the total number perceivable is 161 types of effects for all modes of appearance. The type of effect is named after the psychophysical stimulus (or stimuli) and the relevant color attribute(s), e.g., Luminance-on-hue effect (traditionally known as Bezold-Brucke effect). Each type of effect may include slightly different effects with infinite variations depending on experimental parameters.M. Melgosa was supported by the Ministry of Economy and Competitiveness of the Government of Spain, research project FIS2013-40661-P, with the European Research Development Fund
Optimizing Parametric Factors in CIELAB and CIEDE2000 Color-Difference Formulas for 3D-Printed Spherical Objects
The current color-difference formulas were developed based on 2D samples and there is no standard guidance for the color-difference evaluation of 3D objects. The aim of this study was to test and optimize the CIELAB and CIEDE2000 color-difference formulas by using 42 pairs of 3D-printed spherical samples in Experiment I and 40 sample pairs in Experiment II. Fifteen human observers with normal color vision were invited to attend the visual experiments under simulated D65 illumination and assess the color differences of the 82 pairs of 3D spherical samples using the gray-scale method. The performances of the CIELAB and CIEDE2000 formulas were quantified by the STRESS index and F-test with respect to the collected visual results and three different optimization methods were performed on the original color-difference formulas by using the data from the 42 sample pairs in Experiment I. It was found that the optimum parametric factors for CIELAB were kL = 1.4 and kC = 1.9, whereas for CIEDE2000, kL = 1.5. The visual data of the 40 sample pairs in Experiment II were used to test the performance of the optimized formulas and the STRESS values obtained for CIELAB/CIEDE2000 were 32.8/32.9 for the original formulas and 25.3/25.4 for the optimized formulas. The F-test results indicated that a significant improvement was achieved using the proposed optimization of the parametric factors applied to both color-difference formulas for 3D-printed spherical samples
Hemiepifisiodesis femoral distal mediante biomateriales reabsorbibles: Estudio experimental en el conejo
Se valoró experimentalmente un implante triangular compuesto de 3 tornillos metálicos unidos por un filamento de PDS II o Tendofil como método de epifisiodesis. Se utilizaron conejos esqueléticamente inmaduros, divididos en 4 Grupos, según el seguimiento postoperatorio (1,2,3 y 4 meses), subdivididos a su vez en 2 subgrupos según el filamento empleado. Se colocó el implante en la cara lateral de la epífisis femoral distal izquierda. La extremidad posterior derecha sirvió como control practicándose estudios radiológicos, histológicos e histomorfométrico. Las extremidades intervenidas presentaron una desviación en valgo significativa respecto a las control. El implante utilizado consiguió el frenado misario con ambos filamentos. Durante el primer mes, la eficacia del implante reabsorbible fue comparable al metálico. Posteriormente, el metálico resultó más eficaz. Los estudios histológicos e histomorfométrico mostraron un frenado asimétrico de la fisis intervenida. No hubo daños fisarios en relación con la degradación del implante reabsorbible. Nuestros resultados sugieron el diseño de implantes reabsorbibles en la cirugía del cartílago de crecimiento.A triangular implant compound by 3 metallic screws united by a filament (PDS II vs. Tendofil) as method of experimental epiphysiodesis was evaluated. They were used 32 immature rabbits, divided into 4 Groups acoording to the follow-up (1.2.3. and 4 months), and subdivided according to the employed filament. The implant was located at the lateral face of the distal left femoral epiphysis. The right extremity served as control. Radiographic, histologic and histomorphometric studies were performed. The operated legs presented a significant valgus deviation as compared to controls. The epiphysiodesis was achieved with both types of filaments. During the first month, the efficiency of the absorbable implant was comparable to the metallic. Thereafter, the metallic implant results more effective. Histologic and morphometric studies showed the hemiepiphysiodesis. No physeal damaged in relationship to the degradation of the absorbable implant was observed. Our results suggests the use of absorbable implant in growth plate surgery
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