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The present study investigates the influence of the casks’ wood surface/volume ratio on the extraction processes that take place during the first stages of the production of Sherry Brandy. For this purpose, the ageing of a spirit at 60% alcoholic strength has been examined in casks of two different volumes: 500 L and 250 L, made from three different types of wood: Quercus alba (American oak), Quercus robur (French limousin oak) and Quercus petraea (Spanish oak), either previously seasoned or non-seasoned with Sherry wine.TPI, the sum of all the phenolic compounds analyzed (phenol extraction coefficient) and the variation in color compared to the initial distillate (CIEDE 2000) were evaluated in all the aged distillates. The casks with a higher surface/volume ratio produced brandies that generally presented higher values for all these parameters, with different increments depending on the type of oak wood. The seasoning of the casks reduced the contribution of phenolic compounds from the wood to the ageing spirit and resulted in brandies with a lighter color when aged in French and Spanish oak casks, but not when the American oak casks were used.Four kinetic models have been applied to better understand the evolution of these parameters during the ageing stage: Lagergren, Peleg, Intraparticle and parabolic diffusion. Peleg's model was the best fit in all the cases, which suggests that 2 types of mechanisms are involved in ageing: a rapid and a slow one. Regarding the diffusion models, the results were better fitted to the parabolic model, which suggests that during the ageing of the spirit a number of parallel reactions take place that affect the values actually reached by the parameters considered in our study. It was also observed that higher wood surface/volume ratios resulted in higher values of phenolic compounds in the distillates, but did not represent a significant factor in relation to the color of the final distillates.The sensory analysis of the samples aged for 16 months demonstrated that only the wine spirits aged in French oak wood presented significant differences depending on the size of the cask; however, all the brandies were registered significant differences associated to the seasoning of the casks.

The physical meaning and calculating process of the rheological parameters of two nonlinear rheological models, the parabolic model and the modified Bingham model, were compared. The fluidity test and a rheological experiment on cementitious materials were performed. The Couette inverse problem is a key issue in measuring and solving the rheological parameters of fresh cementitious materials. The solution of the Couette inverse problem based on the modified Bingham model is discontinuous when the coefficient of the quadratic term is equal to zero, resulting in a large deviation between the fitting curve and the rheological experimental data. The credibility of the rheological parameters of the pastes calculated based on the modified Bingham model is low. The formulas for calculating yield stress, fiducial differential viscosity and the degree of shear thickening or shear thinning of the parabolic model have been developed. The credibility of the rheological parameters of the pastes calculated based on the parabolic model is high. The flow performance of the paste can be clearly characterized by the rheological parameters calculated with the parabolic model. [ABSTRACT FROM AUTHOR]

Abstract Kali Lamong River with a trapezoidal channel shape has a bottom width of about 30 m, a top width of 40 m and a depth of 3.5 m. In one of the river segments, the basis is in the form of a fixed bed and it is assumed that there is no sediment transport in this section. On the downstream side after the fixed bed section, the river segment is a mobile bed with river bed material that has an average grain diameter of 1.5 mm, a relative mass density of 2.6, and porosity of 0.3. Flowrate with Q50 is 1000.00 m3/sec with a maximum flow speed of 15 m/sec. Riverbed degradation will occur initially at the upstream point in the fixed and mobile beds. Depth of riverbed degradation calculated by the Parabolic model of 80.00 cm / year based on the solution of the equation.

The quadratic rheology model considers the yield stress, viscous stress, turbulent stress and disperse stress, so it is used in this study to derive the velocity profile of debris flows. The quadratic model with the parabolic eddy viscosity was numerically solved, and an analytical solution was derived for the quadratic model with a constant eddy viscosity. These two solutions were compared with the Arai-Takahashi model that excluded the viscous stress and the yield stress. The three models were tested by using 17 experiment cases of debris flows over rigid beds. The results prove that the quadratic model with parabolic and constant eddy viscosities is applicable to muddy and granular flows, whereas the Arai-Takahashi model tends to overestimate the flow velocity near the water surface if a plug-like layer exists. In addition, the von Karman constant and the zero-velocity elevation in the three models are related to sediment concentration. The von Karman constant decreases first and then increases as the sediment concentration increases. The zero-velocity elevation is below the bed surface, likely due to the invalidity of the non-slip boundary condition for the debris flows over fixed beds. [ABSTRACT FROM AUTHOR]

The purpose of the self-driving car is to minimize the number casualties of traffic accidents. One of the effects of traffic accidents is an improper speed of a car, especially at the road turn. If we can make the anticipation of the road turn, it is possible to avoid traffic accidents. This paper presents a cutting edge curve lane detection algorithm based on the Kalman filter for the self-driving car. It uses parabola equation and circle equation models inside the Kalman filter to estimate parameters of a using curve lane. The proposed algorithm was tested with a self-driving vehicle. Experiment results show that the curve lane detection algorithm has a high success rate. The paper also presents simulation results of the autonomous vehicle with the feature to control steering and speed using the results of the full curve lane detection algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of the self-driving car is to minimize the number casualties of traffic accidents. One of the effects of traffic accidents is an improper speed of a car, especially at the road turn. If we can make the anticipation of the road turn, it is possible to avoid traffic accidents. This paper presents a cutting edge curve lane detection algorithm based on the Kalman filter for the self-driving car. It uses parabola equation and circle equation models inside the Kalman filter to estimate parameters of a using curve lane. The proposed algorithm was tested with a self-driving vehicle. Experiment results show that the curve lane detection algorithm has a high success rate. The paper also presents simulation results of the autonomous vehicle with the feature to control steering and speed using the results of the full curve lane detection algorithm.

A system of segmented detached breakwaters (DBWs) with a gap between units or a harbor breakwater with a shore protection structure at downdrift may result in a salient or tombolo, the curved planform of which can be assessed by the parabolic model. Where two adjacent tips of the DBWs are not at equal distance in the cross-shore direction relative to the wave front, it becomes difficult to accurately locate the common downdrift control point (CDCP) for plotting the asymmetric planform in static equilibrium (SEP). In this study, a simple empirical method is proposed to determine the CDCP and the SEP, using the basic wave angle (β 0 = 65.75°) derived by differentiating the cross-shore component in the parabolic bay shape equation, from which the apex of the isosceles triangle formed by the wave front line and the β 0 line from each wave diffraction point (tip) can be applied to locate the CDCP for plotting the SEP in a double-curvature planform. Following successful benchmark tests with the results calculated by the mean wave energy flux model, many more prototype examples are illustrated to reaffirm the suitability of the simple empirical method for the benefit of coastal scientist, engineer, geomorphologist and manager in the assessment or design of a SEP behind DBWs. • Basic wave angle and downdrift control point in a single static bay shape are derived from parabolic bay shape equation. • Common downdrift control point on asymmetric bay is identified from intersection of two basic wave angle lines of 65.75°. • An accurate simple empirical model is proposed for assessing a double-curvature symmetric and asymmetric bay beach planform (CECI, 2006). [ABSTRACT FROM AUTHOR]

We study the dynamics of a two-level crossing model with a parabolic separation of the diabatic energies. The solutions are expressed in terms of the tri-confluent Heun equations—the generalization of the confluent hypergeometric equations. We obtain analytical approximations for the state populations in terms of Airy and Bessel functions. Applicable expressions are derived for a large part of the parameter space. We also provide simple formulas which connect local solution in different time regimes. The validity of the analytical approximations is shown by comparing them to numerical simulations.

At the center of the macula, fovea plays an important role in computer-aided diagnosis. To locate the fovea, this paper proposes a vessel origin (VO)-based parabolic model, which takes the VO as the vertex of the parabola-like vasculature. Image processing steps are applied to accurately locate the fovea on retinal images. Firstly, morphological gradient and the circular Hough transform are used to find the optic disc. The structure of the vessel is then segmented with the line detector. Based on the characteristics of the VO, four features of VO are extracted, following the Bayesian classification procedure. Once the VO is identified, the VO-based parabolic model will locate the fovea. To find the fittest parabola and the symmetry axis of the retinal vessel, an Shift and Rotation (SR)-Hough transform that combines the Hough transform with the shift and rotation of coordinates is presented. Two public databases of retinal images, DRIVE and STARE, are used to evaluate the proposed method. The experiment results show that the average Euclidean distances between the located fovea and the fovea marked by experts in two databases are 9.8 pixels and 30.7 pixels, respectively. The results are stronger than other methods and thus provide a better macular detection for further disease discovery.

Copyright of Journal of Integrated Coastal Zone Management / Revista de Gestão Costeira Integrada is the property of Associacao Portuguesa dos Recursos Hidricos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Job's method of continuous variations was applied for the determination of the tungsten(VI) to D-(−)-quinic acid {(1 R,3 R,4 S,5 R)-(−)-1,3,4,5-tetrahydroxycyclohexane-1-carboxylic acid} molar ratio in its complex, which is 1:1 at pH 7.50. This paper aims to study the solution equilibria between tungsten(VI) and the ligand at different ionic strengths ranging from (0.1 to 1.0) mol·dm of sodium chloride at T = 298 K. Three models based on the Debye-Hückel equation were investigated for the description of the ionic strength dependence of the stability and dissociation constants. Finally, the stability constant values were compared with the literature data and interpreted on the basis of these ionic strength dependent models. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The results of this research give ionic strength dependence patterns for the complexation of tungsten(VI) with methyliminodiacetic acid at T = 298 K. The formation data reported in this work were obtained at different ionic strengths (0.1 < I/mol·dm < 1.0) of sodium perchlorate on the basis of Job's continuous variation method, which show that a 1:1 complex forms at pH = 7.50. UV experimental data were collected for the calculation of the stability constants according to the extended Debye-Hückel theory, the specific ion interaction theory and the parabolic model. Finally, these three models have been compared. [ABSTRACT FROM AUTHOR]

In this paper, the transient temperature field around a thermally insulated crack in a substrate bonded to a coating is obtained using the hyperbolic heat conduction model. Fourier and Laplace transforms are applied, and the thermal conduction problem is reduced to solving a singular integral equation. Numerical results show that the hyperbolic heat conduction parameters, the heat conductivity of the substrate and coating, and the geometric size of the composite have significant influence on the transient temperature field. In the case of very small time scales, the results predicted by the hyperbolic model are more conservative than that by the parabolic model. [ABSTRACT FROM AUTHOR]

In this research the interaction of dioxovanadium(V) with iminodiacetic acid has been considered at 25 °C and pH=1.00-2.50 in an ionic strength range of 0.1 to 1.0 mol⋅dm of NaClO by UV spectrophotometric and potentiometric techniques. Only one species, VOHL, was assumed on the basis of two stoichiometric models. The extended Debye-Hückel theory predicts the first order effects in simple electrolyte solutions. Interactions between the reacting species and the ionic medium are taken into account in the specific ion interaction model. Parabolic, specific ion interaction, and extended Debye-Hückel models have been compared and it has been shown that the parabolic model with two coefficients is satisfactory for this complexation reaction. The results have also been compared with the literature values. [ABSTRACT FROM AUTHOR]

The main aim of this research is to study the complexation of molybdenum(VI) with methyliminodiacetic acid in NaClO4 aqueous solutions at pH = 6.00 and ionic strengths (0.1< I/mol⋅dm−3<1.0) at 25 °C by using potentiometric and UV spectrophotometric measurements in order to obtain thermodynamic stability constants at I=0 mol⋅dm−3. A comparison with previous literature data was made for the stability constants, though few data were available. The stability constants data have been analyzed and interpreted by using extended Debye-Hückel theory, specific ion interaction theory and parabolic model. Finally it might be concluded that parabolic model applies better for this complexation reaction. [ABSTRACT FROM AUTHOR]

The two most important concepts in transport phenomena in the past century are that of transfer and dispersion coefficient. While both concepts reduce the local degrees of freedom and provide a coarse-grained low-dimensional description of the transport process at the macroscale, their physical interpretations and mathematical descriptions differ. The transfer coefficient concept uses two concentration or temperature modes and upscales the microscale molecular effects as an exchange between the local and global scales, leading to hyperbolic models and Cauchy (initial value) problems. The dispersion coefficient concept uses a single mode and incorporates the microscale effects as an effective diffusion or dispersion term in the macroscale transport equation and leads to parabolic models and requires additional boundary conditions or physical constraints. We examine here the application of these concepts for reacting systems and provide some guidelines for their proper use in the low-dimensional description of reacting as well as non-reacting systems. [ABSTRACT FROM AUTHOR]

It is widely accepted that light availability sets the lower limit of seagrass bathymetric distribution, while the upper limit depends on the level of disturbance by currents and waves. The establishment of light requirements for seagrass growth has been a major focus of research in marine ecology, and different quantitative models provide predictions for seagrass lower depth limits. In contrast, the influence of energy levels on the establishment, growth, and maintenance of seagrasses has received less attention, and to date there are no quantitative models predicting the evolution of seagrasses as a function of hydrodynamics at a large scale level. Hence, it is not possible to predict either the upper depth limit of the distribution of seagrasses or the effects that different energy regimes will have on these limits. The aim of this work is to provide a comprehensible methodology for obtaining quantitative knowledge and predictive capacity for estimating the upper depth limit of seagrasses as a response to wave energy dissipated on the seafloor. The methodology has been applied using wave data from 1958 to 2001 in order to obtain the mean wave climate in deep water seaward from an open sandy beach in the Balearic Islands, western Mediterranean Sea where the seagrass Posidonia oceanica forms an extensive meadow. Mean wave conditions were propagated to the shore using a two-dimensional parabolic model over the detailed bathymetry. The resulting hydrodynamics were correlated with bottom type and the distribution of P. oceanica. Results showed a predicted near-bottom orbital velocity of between 38 and 42 cm s-1 as a determinant of the upper depth limit of P. oceanica. This work shows the importance of interdisciplinary effort in ecological modeling and, in particular, the need for hydrodynamical studies to elucidate the distribution of seagrasses in shallow depths. Moreover, the use of predictive models would permit evaluation of the effects of coastal activities (construction of ports, artificial reefs, beach nutrient-input, dredging) on benthic ecosystems. [ABSTRACT FROM AUTHOR]