Search results for "Ady"
showing 10 items of 565 documents
Experimental System Identification and Black Box Modeling of Hydraulic Directional Control Valve
2015
Directional control valves play a large role in most hydraulic systems. When modeling the hydraulic systems, it is important that both the steady state and dynamic characteristics of the valves are modeled correctly to reproduce the dynamic characteristics of the entire system. In this paper, a proportional valve (Brevini HPV 41) is investigated to identify its dynamic and steady state characteristics. The steady state characteristics are identified by experimental flow curves. The dynamics are determined through frequency response analysis and identified using several transfer functions. The paper also presents a simulation model of the valve describing both steady state and dynamic charac…
Generalization of a finite-difference numerical method for the steady-state and transient solutions of the nernst—planck flux equations
1985
Abstract A generalization of the numerical method of Brumleve and Buck for the solution of Nernst—Planck equations when convective flux and electric current are involved has been developed. The simulation procedure was applied to a specific case: transport of strong electrolytes in a wide-pore membrane with simultaneous diffusion, convection and electric current. Good agreement was found between experimental data and computed results.
Synthesis and characterization of vanadyl(IV) complexes of Schiff bases derived from anthranilic acid and salicylaldehyde (or its derivatives) or ace…
1997
Anhydrous, dimeric vanadyl(IV) complexes of Schiff bases derived from [1+1] condensation of salicylaldehyde (or its derivatives) and anthranilic acid, have been synthesized from CH3CN and were characterized by elemental analysis, FTIR, EPR, absorption, TGA, cyclic voltammetry and room temperature magnetic susceptibility measurements. These complexes were found to be oxidized by air in polar solvents like MeOH and DMF to V-V products. The E(1/2) values were found to be around 660 mV indicating that the carboxylate group favours vanadyl(IV) binding when compared to the alkoxo-bound vanadium complexes. Oxidative instability of these complexes are dependent on the substituent on the salicylalde…
Improving diagnostic accuracy of MDCT coronary angiography in patients with mild heart rhythm irregularities using ECG editing
2006
OBJECTIVE. The objective of our study was to compare diagnostic accuracy of MDCT coronary angiography in a population of patients with mild heart rhythm irregularities before and after editing the ECG. SUBJECTS AND METHODS. Thirty-eight patients who underwent MDCT coronary angiography and conventional coronary angiography were enrolled in the study. The inclusion criterion was the presence of mild heart rhythm irregularities (i.e., premature beats; atrial fibrillation; mistriggering; or low heart rate, defined as 40 beats per minute or less) during the scan. All patients underwent MDCT with the following parameters: 16 detectors; collimation, 0.75 mm; gantry rotation time, 375 msec; 120 kV;…
Kerr Optical Frequency Combs With Multi-FSR Mode Spacing in Silica Microspheres
2021
We experimentally demonstrate Kerr optical frequency combs (OFCs) with mode spacing of 1, 2, 3, 5, 6, and 8 free spectral ranges (FSRs) corresponding to 0.4, 0.8, 1.2, 2, 2.4, and 3.2 THz, respectively, in silica microspheres pumped by CW C-band lasers in the anomalous dispersion range. Experimental realizations are based on using standard telecom equipment and components such as SMF-28e fiber for producing microspheres and fiber tapers for pump coupling and OFC outcoupling. Numerical simulation is performed to support the experimental results and explain the observed spectral asymmetry in OFCs by the influence of the 3rd-order dispersion.
Analyse expérimentale et numérique du comportement de véhicules terrestres en présence d'un vent latéral instationnaire
2013
The automotive manufacturers are nowadays more and more interested in crosswind aerodynamics. Indeed, the driver is subjected every day to strong side air flows, for example when overtaking another vehicle or when passing through a lateral wind wall, generated by terrain topography (as in the case of the passage near the empty space between two buildings).The aerodynamic efforts generated in these situations can lead to undesired lateral deviations,which can be dramatic if the driver is surprised. Different experimental studies, reproducing the effects of a dynamic yaw angle, pointed out the issues of the steady methods, commonly used to qualify the vehicle crosswind behaviour. Little is st…
Biopsia selectiva del ganglio centinela en pacientes con cáncer de mama. Efecto de la quimioterapia neoadyuvante y grado de respuesta clínica y patol…
2015
El cáncer de mama es, globalmente, la neoplasia más frecuente en mujeres. En 2012 se calcularon 1.7 millones de nuevos casos en el mundo, representando el 12% de todos los cánceres y el 25% de los cánceres en mujeres. el diagnóstico y tratamiento del cáncer de mama se sustenta en un conjunto de especialistas que forman parte de equipos multidisciplinares que incluyen principalmente a oncólogos, radiólogos, médicos nucleares, patólogos y cirujanos. Durante muchos años los ganglios axilares en los niveles I/II eran extirpados de forma rutinaria, procedimiento que se asociaba con una morbilidad significativa, que incluía hasta un 20% de riesgo de linfedema, dolor y disfunción en hombro y brazo…
Factores pronósticos en el cáncer de recto localmente avanzado tratado con quimioradioterapia neoadyuvante seguida de cirugía. Valor pronóstico del N…
2016
Antecedentes: La quimioradioterapia neoadyuvante es parte del tratamiento estándar del cáncer de recto localmente avanzado. Diferentes variables patológicas y clínicas van a ayudar a estimar el riesgo de recaída o muerte de cada paciente. Valentini et al. desarrollaron tres nomogramas que predicen la probabilidad de recaída local, recaída sistémica y muerte en pacientes con cáncer de recto tratado con quimioradioterapia neoadyuvante. El Neoadjuvant Rectal Score se ha desarrollado a partir del nomograma de Valentini para la supervivencia global utilizando las tres variables con mayor peso relativo: cT, ypT e ypN. Objetivos: Analizar las diferentes variables pronósticas preoperatorias, relaci…
High Reynolds number Navier-Stokes solutions and boundary layer separation induced by a rectilinear vortex
2013
Abstract We compute the solutions of Prandtl’s and Navier–Stokes equations for the two dimensional flow induced by a rectilinear vortex interacting with a boundary in the half plane. For this initial datum Prandtl’s equation develops, in a finite time, a separation singularity. We investigate the different stages of unsteady separation for Navier–Stokes solution at different Reynolds numbers Re = 103–105, and we show the presence of a large-scale interaction between the viscous boundary layer and the inviscid outer flow. We also see a subsequent stage, characterized by the presence of a small-scale interaction, which is visible only for moderate-high Re numbers Re = 104–105. We also investi…
PREDICTION OF HARVEST TIME IN PEACH [PRUNUS PERSICA (L.) BATSCH] FRUIT USING THE DA-METER
2015
The aim of this work was to define the most appropriate time of harvesting early ripening peach fruit using destructive and non-destructive quality indexes such as the index of absorbance (IAD), measured with the DA-Meter, a portable equipment able to measure the degradation of chlorophyll in the pericarp. In this context our research was carried out in 2009 and 2010 on several peach cultivars. Total soluble solid content increased while flesh firmness and total acidity decreased with IAD values, but no significant correlation was found between destructive and non-destructive parameters.