Jesus Alpuente

Jesus Alpuente
University of Alcalá | UAH · Department of Signal and Communications Theory

PhD

About

31
Publications
7,083
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
228
Citations
Citations since 2017
4 Research Items
121 Citations
20172018201920202021202220230510152025
20172018201920202021202220230510152025
20172018201920202021202220230510152025
20172018201920202021202220230510152025

Publications

Publications (31)
Article
Full-text available
Acoustic analysis of materials is a common non-destructive technique, but most efforts are focused on the ultrasonic range. In the audible range, such studies are generally devoted to audio engineering applications. Ultrasonic sound has evident advantages, but also severe limitations, like penetration depth and the use of coupling gels. We propose...
Article
Full-text available
The aim of this study is the detailed calculation of microwave propagation inside raw timber in cylindrical configurations. Two different approaches have been used. The first one uses an exact formulation and analytical approximations in order to explore the electromagnetic field distribution inside dry wood. The introduction of conductivity in the...
Article
Electromagnetic radiowave exposure is a major concern in most countries due to possible adverse health effects. Over the last 10years, many technological changes (digital television, mobile technologies, wireless networks…) have led to variations in the electromagnetic field (EMF) levels. A large number of studies devoted to the analysis of EMF lev...
Article
Full-text available
The main aim is to test the influence of anatomical structure (grain direction and elements size), wood hardness and machining conditions on wood surface roughness. 180 samples defect-free were obtained from beech, oak and pine and processed with different machining methods (planning, sanding with 60 grit or sanding with 180 grit). Roughness, hardn...
Article
Full-text available
In this work a simple technique to obtain information about the species of wood samples using stress-wave sounds in the audible range is presented. However, spectra of wood sounds generated by pendulum impact are very complex and feature extraction for classification purposes is very difficult. Polyspectral techniques have been successfully applied...
Conference Paper
This paper presents a low profile multiband antenna suitable for future wireless communication systems. The design comprises a co-planar fed patch antenna and a planar inverted-F antenna (PIFA). Active switching enables the antenna to resonant in different lower frequency bands while maintaining fixed operational performance in the upper bands.
Article
Full-text available
B o l e t í n d e I n formac Ión t écn Ica n º 284 tecnología 1.-Introducción La automatización se ha entendido como la tecnología a la cual se aplican los sistemas mecánicos, electrónicos y computarizados, con el fin de operar y controlar la producción, de bienes físicos de consumo, además involucra una gran variedad de sistemas y pro-cesos que se...
Article
Full-text available
Palatal clicks are most interesting for human echolocation. Moreover, these sounds are suitable for other acoustic applications due to their regular mathematical properties and reproducibility. Simple and nondestructive techniques, bioinspired by synthetized pulses whose form reproduces the best features of palatal clicks, can be developed. The use...
Article
Full-text available
Stress-wave analysis is a powerful and flexible technique to study mechanical properties of many materials. We present a simple technique to obtain information about the species of wood samples using stress-wave sounds in the audible range generated by collision with a small pendulum. Stress-wave analysis has been used for flaw detection and qualit...
Article
Full-text available
In the first part of this work we studied several oral signals suitable for human echolocation. Palatal clicks were proven to be optimal pulses for this task. In the second part of this series, we analyze, from a physical and psychoacoustical point of view, the sounds produced by hand clapping and finger snapping. One additional sound is studied: a...
Article
Possible mass and bone density alterations were studied in second-generation OF1 mice exposed chronically since birth to a magnetic field of 50 Hz and 15 μT. For that purpose, 120 animals were sacrificed at the age of 12 weeks (males) and 14 weeks (females) and their femurs studied by bone densitometry. A total of 24 parameters in two groups (densi...
Article
Full-text available
Differential interference contrast microscopy is a very powerful optical technique for microscopic imaging. Inspired by the physics of this type of microscope, we have developed a series of image processing algorithms aimed at the magnification, noise reduction, contrast enhancement and tissue analysis of biological samples. These algorithms use fr...
Article
Full-text available
Active human echolocation can be an extremely useful aid for blind people. Active echolocation can be trained with both artificial and organic signals. Organic signals offer some advantages over artificial ones. Very detailed studies of organic signals in animals have been done. However, in the case of humans, the scientific literature is very scar...
Article
Speckle noise reduction techniques are very important for the enhancement and preprocessing of SAR and many medical images. We present a fast and efficient algorithm, based on fractal convolutions, to reduce speckle noise in real SAR images. The results of this approach are compared with other classical noise reduction techniques.
Article
Full-text available
A simple and inexpensive method for the qualitative characterization of wood surfaces is presented.It is based on the iterative autocorrelation of laser speckle patterns produced by diffuse laser illumination of the wood surfaces.The method exploits the high spatial frequency content of speckle images.A similar approach with raw conventional photog...
Article
Full-text available
An accurate full vectorial treatment of the leaky modes in Bragg fibres with high refractive index variations is presented. The model can describe arbitrary functions of the relative permittivity inside the fibre. Boundary conditions are substituted by smooth continuous functions. This allows the use of very precise numerical and analytical approac...
Article
Full-text available
Complete vectorial studies of electromagnetic wave propagation in complex media are difficult and computationally intensive. A mathematical continuous model can simplify some of such difficulties. Using this technique, we have modeled the propagation of electromagnetic plane waves through a semiinfinite photonic crystal with defects. The model is e...
Article
This paper presents a low cost system developed for finding vehicles by means of a GPS system. By using several applications, it is possible to know the position of a vehicle on a map, send messages... The applications are independent of the employed radiocomunication system. Circuitry has been developed with commercial devices and different applic...
Article
Full-text available
This paper presents a low cost system developed for finding ships by GPS, as well as its localization in a map. Circuitry has been developed from marketed devices and an application has been programmed that allows the easy administration of the own fleet. In this way, you have a modular system designed, in which technological updates can be easily...
Conference Paper
The main objective of this work is to develope a software tool that allows studying the reticular network planning in hectometrics wavelengths. This tool is intended to perform the pratical teaching about surface wave broadcasting in the educational laboratory. The program has been developed using MATLAB 6.
Article
Full-text available
We propose a new approach to solve the problem of the propagation of electromagnetic waves in unidimensional media with an arbitrary variation of their dielectric permittivity. This method is deduced from the Maxwell equations with a minimum of approximations and allows a full vectorial description of both the electric and magnetic fields through t...
Article
Full-text available
RESUMEN En este trabajo se presenta un nuevo método de diseño de filtros prototipo de alta calidad para transmultiplexores cercanos a la reconstrucción perfecta. Esta técnica de diseño se diferencia de las propuestas por otros autores en la función de coste que se hace mínima, así como en la técnica de diseño del filtro FIR. Se incluyen varios ejem...
Article
Full-text available
We present in this paper a software tool that let the user simulate the overall optical system response. We can evaluate it for those ones that use either rectangular pulses or digitally modulated signals in order to transmit information by means of optical fibber, monomode or multimode, and in first, second or third optical window. This applicatio...
Article
Full-text available
This paper presents a software tool developed for simulating optical communications systems. The optical system is divided into three main parts: transmitter, optical fibber and receiver. The simulation allows the determinations of the spectral and frequency responses of each block and the whole system. The program allows the simulations of the dif...
Article
Full-text available
This paper describes the development of a tool for the application of the knowledge on waveguides, and its equivalent transmission line model to the design of several microwave waveguide circuits. We purpose the creation of user's models for the simulation program MMICAD, starting from the equivalent circuits of discontinuities in rectangular and c...
Article
Full-text available
INTRODUCCIÓN La importancia, cada vez más evidente, de las estaciones depuradoras de aguas residuales (EDAR) radica en la facilidad de regenerar el recurso agua, para su reutilización en diversas actividades socioeconómicas o devolverlo a la naturaleza con la mayor calidad posible. Todo ello con un mínimo de impacto ambiental. Actualmente se aplica...

Network

Cited By

Projects

Project (1)
Project
Researching new highly penetrating, no ionizing, high quality imaging sensors for medical and nondestructive testing applications.