Constanza Rubio

Constanza Rubio
Universitat Politècnica de València | UPV · Department of Applied Physics

Doctor of Philosophy

About

93
Publications
21,990
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,021
Citations
Citations since 2016
61 Research Items
934 Citations
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200

Publications

Publications (93)
Article
Full-text available
To study the first impact of the COVID-19 crisis on the results obtained by students belonging to the School of Agricultural Engineering and Environment at the Universitat Politècnica de València (Spain), the average of the marks corresponding to three academic years (2016–2019) was compared to those obtained in 2019–2020 for a total of four bachel...
Article
In this paper, the analytical and numerical solutions of a non-steady state mathematical model are developed and analyzed. The mathematical model development of a non-steady state heat transport for a one-dimensional system is shown, and the analytical solution of the model is presented. The numerical solution of the model, using the finite element...
Conference Paper
In many engineering degrees courses, Physics is a fundamental pillar from which the rest of the subjects of the degree are formed. This fundamental nature is perceived by students as subjects with no connection to the degree that they aspire to achieve. Moreover, the students' level of education is very heterogeneous, especially in the firsts cours...
Article
Full-text available
World agriculture is facing a great challenge since it is necessary to find a sustainable way to increase food production. Current trends in advancing the agriculture sector are based on leveraging remote sensing technology and the use of biostimulants. However, the efficient implementation of both of these on a commercial scale for the purposes of...
Article
Full-text available
Rice is considered one of the most important crops in the world. According to the Food and Agriculture Organization of the United Nations (FAO), rice production has increased significantly (156%) during the last 50 years, with a limited increase in cultivated area (24%). With the recent advances in remote sensing technologies, it is now possible to...
Article
In this paper we present a new way to obtain tunable acoustic hooks. The breaking of the symmetry of the material composition is used for the generation of acoustic hooks from Janus cylinders. This fact is possible by using sonic crystals to vary the refractive index of two half-cylinders. The study has been carried out numerically, using the Finit...
Article
Full-text available
In this study, we report the characteristics of acoustic jets obtained through a mesoscale (radius less than 5 wavelengths) ABS cylinder made with a 3D printer. We have analyzed the influence of cylinder size on the characteristic parameters of an acoustic jet, such as maximum acoustic intensity at focus, Full Width at Half Maximum and length of Ac...
Article
Full-text available
Fresnel Zone Plates are planar lenses that can be used to focus ultrasound beams. This kind of acoustic lenses can play a key role in the resolution of ultrasonic NDT systems. In this type of pulse-echo applications, the pulse duration is an important parameter that specifies the axial resolution, and thus, shorter ultrasound pulses provide higher...
Article
Full-text available
The ability of focus waves with concave or convex surfaces is well known both in optics and in acoustics. Nowadays, the possibility of beamforming sound with flat lenses is a hot topic because of its application in different areas such as biomedical engineering or non-destructive techniques. In this paper, we propose a gas filled cuboid lens that h...
Article
Full-text available
In this paper, we demonstrate that, contrary to what the Geometrical Optics laws dictate, a flat polymer mesoscale cuboid immersed in water with no need of negative refraction can focus sound. Two main polymers were considered and lens parameters compared: PMMA and Rexolite®. It was concluded that Rexolite® is preferable for acoustic jet formation....
Article
Full-text available
In this work, we report the first experimental observation of a new type of near-field curved acoustic beam confirmed by simulations. This new curved acoustical beam is generated by asymmetric distribution of the vortices in a polymer Janus particle (particle with broken symmetry) immersed in water. The origin of the vortices is in the conversion o...
Article
Full-text available
In this work, we present a bifocal Fresnel zone plate (BiFZP) capable of generating focusing profiles with two different foci. The performance of the BiFZP is demonstrated in the ultrasound domain, with a very good agreement between the experimental measurements and the finite element method (FEM) simulations. This lens becomes an appealing alterna...
Article
Full-text available
A method of detecting dielectric objects hidden behind an opaque barrier located on a reflective background, based on the distortion of interference fringes, is proposed in this article. Experiments conducted in the millimeter wavelength range demonstrated the effectiveness of the method under consideration, which does not require a holographic ima...
Conference Paper
We predict acoustic super resonance modes with a field-intensity enhancement several tens of thousands of times higher (order of magnitude: 10⁴–10⁵) with the support of dielectric mesoscale spheres submerged in water, by means of numerical simulations. The super resonances are related to the internal dispersion in specific values of both Mie and pa...
Article
Full-text available
In this work, we report the focusing effect of a 2D sonic crystal cuboid. The proposed sonic composite lens is vertically extended from a 2-D flat Phononic Crystal Structure, but it is found to be able to focus waves in a three-dimensional manner. By varying the cuboid size, beam dimensions change and transverse beam width values smaller than the c...
Article
In this work, we demonstrate the application of Cantor fractal lenses in acoustics. The Cantor Zone Plate (CZP), previously introduced in optics, is designed from a conventional Fresnel Zone Plate (FZP) using a binary sequence governed by the distribution of a generalized Cantor set. The CZP maintains its main focus at the same focal distance than...
Article
In this work, we present a lens based on a thin hollow ABS spherical container structure, which can be filled up with different compatible liquids. The acoustic jet can be dynamically shaped by either shifting the operating frequency or modifying the geometry of the lens. We show for the first time that a spherical Ethanol ABS core-shell acoustical...
Article
Full-text available
This work analyzes the influence of the distribution of transparent Fresnel regions over the focusing profile of Soret Zone Plates. It is shown that this effect becomes very significant in those fields where directional transducers are employed, such as microwaves or acoustics. A thorough analysis on both the lens transmission efficiency and the fo...
Preprint
Full-text available
In this work, we report the observation of a new type of near-field curved acoustic beam different from the Airy-family beams both through simulations and experiment. This new self-bending acoustical beam is generate from a rectangular trapezoid of a polymer material immersed in water and has unique features. The radius of curvature of acoustical h...
Article
Full-text available
The development of flat acoustic lenses for different applications such as biomedical engineering is a topic of great interest. Flat lenses like Fresnel Zone Plates (FZPs) are capable of focusing energy beams without the need of concave or convex geometries, which are more difficult to manufacture. One of the possible applications of these type of...
Article
Full-text available
Per the laws of geometrical optics, a plane-parallel medium does not possess focusing properties. However, in this paper, we demonstrate for the first time that an acoustic cuboid particle filled with CO2 is able to focus sound despite its flat surface. It is worth noting that traditional lenses focus sound through their curved surfaces. We report...
Article
The possibility of modulating the ultrasound beam produced by a transducer through lenses has become an important task. The fact that these lenses are flat, facilitates their design, construction and applications. If, in addition, the design itself incorporates geometries that affect differently the foci profile on the axial axis of the lens, impro...
Article
Full-text available
The image performance of acoustic and ultrasound sensors depends on several fundamental parameters such as depth of focus or lateral resolution. There are currently two different types of acoustic diffractive lenses: those that form a diffraction-limited spot with a shallow depth of focus (zone plates) and lenses that form an extended focus (quasi-...
Conference Paper
Full-text available
Fresnel Zone Plate lenses present a high capacity to generate focus spot. In acoustics, these ultrasound lenses can be used in both HIFU and imaging systems. One of the limitations of classical Fresnel Zone Plates is the difficulty to control either the lateral lobes or the length of the focus. These focal geometric parameters are directly related...
Article
Full-text available
Zone plate lenses are used in many areas of physics where planar geometry is advantageous in comparison with conventional curved lenses. There are several types of zone plate lenses, such as the well-known Fresnel zone plates (FZPs) or the more recent fractal and Fibonacci zone plates. The selection of the lens material plays a very important role...
Article
In acoustical lenses both resolution and depth of focus are determined by diffraction and the smaller the lens aperture the worse the resolution and the greater the depth of focus. Diffraction-limited resolution has a Soret Zone Plate, but a long depth of focus has an axicon. Nevertheless, these are two different devices each of which requires its...
Article
In this letter, the improvement in focus by the use of a pupil mask produced in an acoustic mesoscale cuboid particle filled with CO2 is reported. Thereby, the result shows that the pupil mask increases the sound intensity and also increases the resolution (or a reduction of the full width at half maximum, FWHM) in focus compared to the non-masked...
Article
Full-text available
The capability of focusing of a novel acoustic lens based on mesoscale acoustic cuboid particle filled with CO2 gas is analysed. This flat lens is able to focus sound in the same way that conventional curved acoustic lenses do. It is shown that the sound speed inside the cuboid is the responsible for this effect. By changing the percentage of CO2,...
Preprint
The image performance of acoustic and ultrasound sensors depends on several fundamental 1 parameters such as depth of focus or spatial resolution. There are currently two different type 2 of acoustic diffractive lenses: those which form a diffraction-limited spot with a shallow depth 3 of focus (zone plates) and lenses which form an extended focus...
Article
Full-text available
Traditional acoustic lenses modulate the ultrasonic beam due to their curved surfaces and the refractive material of which they are made. In this work, a different type of acoustic lens, based on Polyadic Cantor Fractals (PCF), is presented and thoroughly analyzed. These new Polyadic Cantor Fractal Lenses (PCFLs) are completely flat and easy to bui...
Article
Full-text available
The design of zone plates is an important topic in many areas of physics, such as optics, X-rays, microwaves or ultrasonics. In this paper, a zone plate design method, which provides high flexibility in the shaping of the focusing profile, is analyzed. This flexibility is achieved through the use of binary sequences that produce zone plates with di...
Article
The manipulation of focal patterns of acoustic underwater Soret Zone Plate lens in far fields, such as manipulation (optimization) of Sidelobe Level and the design of long depth of focus by selecting the simple free parameter called reference radius (phase) has been demonstrated.Two effects have been studied by means of numerical simulations. Regar...
Article
The Talbot effect using ultrasonic waves transmitted through a periodic perforated plate is presented. The ultrasonic wave-field at the exit of the perforated plate replicates the perforated pattern at the Talbot distance. Experimental results are validated by an analytical model. The measured propagating wave-field is consistent with the analytica...
Article
Full-text available
El análisis del campo sonoro en un recinto está incluido en los contenidos que forman parte del temario de las asignaturas relacionadas con la acústica de recintos. Sin embargo, los alumnos a menudo encuentran dificultades con la comprensión y visualización espacial de los modos propios de vibración que tienen lugar en el interior del recinto. Por...
Article
A new open, thin and low frequency acoustic barrier is presented. These barriers, based on arrays of isolated pickets produce high acoustic attenuation in a selective range of frequencies related to their geometry and distribution. These open barriers are acoustically competitive with traditional ones, which are based on continuous and rigid materi...
Conference Paper
Full-text available
La programación y la robótica son algunas de las disciplinas que han invadido las aulas con el objetivo de desarrollar una de las competencias consideradas de mayor relevancia en la educación de hoy día: el Pensamiento Computacional. El Pensamiento Computacional ayuda a estructurar la mente, aportando las herramientas necesarias para resolver probl...
Article
Full-text available
In this work, the distortion of the Fresnel Zone Plate focusing profile generated by a piston emitter in ultrasound applications is significantly reduced through the use of phase correction rings, which compensate the effect of the piston emitter radiation diagram. Both simulation and experimental results demonstrate the improvement achieved with t...
Article
Full-text available
The focusing properties of Fresnel Zone Plates (FZPs) against frequency are analyzed in this work. It is shown that the FZP focal length depends almost linearly on the operating frequency. Focal depth and focal distortion are also considered, establishing a limit on the frequency span at which the operating frequency can be shifted. An underwater F...
Conference Paper
The interest of passive focusing lenses for ultrasonic use has grown in the last decade. Traditional acoustic lenses are capable of modulating the ultrasonic beam, where their ability to focus and guide waves comes from the fact that they are constructed of refractory materials with curved surfaces. In this work, lenses capable of modulating the ul...
Conference Paper
Full-text available
Nowadays, due to the problems that exist in terms of noise pollution and its impact on health, it is common to use acoustic barriers1. Traditionally, these barriers consisted of rigid and continuous materials that are interposed between the source and the receiver2. However, there are situations in which the characteristics of the problem necessita...
Chapter
Full-text available
The term fractal was coined in 1975 by Benoit Mandelbrot. Since then, fractal structures have been widely used by the international scientific community. Its range of applications includes multiple areas, such as optics, physics, cryptography, medicine, economics, and so on. The application of fractal structures to modulate light beams in the field...
Article
Full-text available
The focusing capabilities of a pinhole zone plate lens are presented and compared with those of a conventional Fresnel zone plate lens. The focusing properties are examined both experimentally and numerically. The results confirm that a pinhole zone plate lens can be an alternative to a Fresnel lens. A smooth filtering effect is created in pinhole...
Conference Paper
Full-text available
El presente trabajo recoge parte de los resultados obtenidos en el marco del proyecto de innovación docente “Herramientas para la planificación, realización y valoración de los Trabajo Fin de Grado (TFGs)”. Se pretende resolver la problemática a la que se enfrenta el alumnado, los tutores y los tribunales en cuanto a los criterios de valoración de...
Article
Fresnel zone plates (FZPs) focus waves through constructive interference of diffracted fields. They are used in multiple fields, such as optics, microwave propagation or acoustics, where refractive focusing by conventional lenses is difficult to achieve. FZPs are designed to work and focus at a design frequency. At this frequency, the behavior of t...
Article
Fresnel Zone Plates (FZPs) become an interesting alternative to traditional lenses when planar fabrication is advantageous, and are used in a wide range of physical disciplines such as optics,microwave propagation, or ultrasounds. Conventional FZPs produce a single focus, which is optimal in most applications. However, certain medical applications,...
Chapter
Full-text available
One of the main environmental problems of the industrialised countries is the noise, which can be defined as an unwanted or unpleasant outdoor sound generated by transport, industry and human activities in general. When it is not possible to reduce the emission of noise acting on the source, the reduction of noise levels in its transmission phase u...
Conference Paper
Full-text available
In the teaching sphere and especially in musical and artistic education it is frequent to learn by imitation. It is a primary instinct and inherent to human beings and of great value, since involuntarily we acquire new insight into the own the prosody of musical dialog and it favors the hearing development. In addition to the sound imitation, there...
Conference Paper
Musical acoustics is a branch of physics that studies the wave phenomena related to the music field. This field is applied in order to teach at undergraduate and postgraduate levels. Nowadays, one of the mean educational targets is the comprehension of this phenomena by high degree music students only with easy mathematics tools. The purpose of thi...
Conference Paper
Full-text available
Abstract During a comparative analysis of the impedance response of several trombones in the same tessitura, completed with a subjective survey, it was found that the Bach model 42 was working like one with less quality. A priori, it was one of the instruments that offered the greatest guarantee within the group studied. Against all odds, after per...
Conference Paper
One of the most important purposes when designing an ultrasonic lens, focuses on improving targeting the waves. On the other hand, it is well known the great scientific interest in structures that follow fractal geometries, having been used in multiple applications. The improvements, of a set of annular scatterers following a fractal growing, in fo...
Article
Full-text available
Underwater ultrasonic transmissions for fluid-solid and air-solid phononic brass plates are reported in this work. Although the structure is roughly the same, experimental results show very different behaviour between fluid-solid and air-solid phononic plates, due to most of the properties of the fluid-solid perforated plates rely on Fabry-Perot re...