Javier Calpe - Academia.edu (original) (raw)

Papers by Javier Calpe

Frontiers in Pediatrics, Apr 11, 2023

Frontiers in Pediatrics 01 frontiersin.org for the evaluation of the effectiveness and safety of ... more Frontiers in Pediatrics 01 frontiersin.org for the evaluation of the effectiveness and safety of antihypertensive treatment and furthermore remains more accessible in primary care than 24-h ambulatory blood pressure. A grading system of the clinical evidence is included.

IEEE Signal Processing Letters, 2023

Frontiers in Cardiovascular Medicine

Accuracy of blood pressure (BP) measurement is important for the evaluation of hypertension in ch... more Accuracy of blood pressure (BP) measurement is important for the evaluation of hypertension in children and adolescents, and it is critically dependent upon the accuracy of the BP measuring device. A device that could pass validated protocols with reliable accuracy would be desirable in clinical and research settings. Several scientific organizations have published recommendations on the validation of different BP measuring devices. Most of them focus on adults but separate recommendations and validation criteria for BP devices intended for use in children and adolescents are included in some validation protocols. In this review, we compare the validation criteria for BP measuring devices among consensus documents from different scientific organizations focusing on the pediatric population and we discuss the evidence gaps targeting the needs for validated BP measuring devices in children and adolescents. We also highlight common pitfalls in the validation studies of BP measuring dev...

Frontiers in Pediatrics

The joint statement is a synergistic action between HyperChildNET and the European Academy of Ped... more The joint statement is a synergistic action between HyperChildNET and the European Academy of Pediatrics about the diagnosis and management of hypertension in youth, based on the European Society of Hypertension Guidelines published in 2016 with the aim to improve its implementation. Arterial hypertension is not only the most important risk factor for cardiovascular morbidity and mortality, but also the most important modifiable risk factor. Early hypertension-mediated organ damage may already occur in childhood. The duration of existing hypertension plays an important role in risk assessment, and structural and functional organ changes may still be reversible or postponed with timely treatment. Therefore, appropriate therapy should be initiated in children as soon as the diagnosis of arterial hypertension has been confirmed and the risk factors for hypertension-mediated organ damage have been thoroughly evaluated. Lifestyle measures should be recommended in all hypertensive childre...

2017 Spanish Conference on Electron Devices (CDE), 2017

The growing demand from the automotive industry for high accuracy magnetic sensors and the need t... more The growing demand from the automotive industry for high accuracy magnetic sensors and the need to perform high resolution angular position measurements have been the drivers for the industrial research in magnetic sensing technologies. This paper describes the design and characterization of several experimental devices implementing simple magnetoresistive structures targeting contactless current measurement in the tens to hundreds of milliamps range with sub-mA resolution. The ultimate goal is to extend the application area of magnetoresistive sensors beyond their current niche in automotive into more general applications. The initial set of devices tested to-date has shown a sensitivity of 0.18 mV/mA in ±100 mA range when supplied from a 4V supply, which is a close match to the theoretically calculated value of 0.23 mV/mA. The linearity and hysteresis error within the ±100 mA full scale (FS) were better than 2% FS and 0.45% FS respectively, when configured as Wheatstone bridges.

a series of events initiated in 2008, capturing the advances on special circuits, electronics, an... more a series of events initiated in 2008, capturing the advances on special circuits, electronics, and microelectronics on both theory and practice, from fabrication to applications using these special circuits and systems. The topics cover fundamentals of design and implementation, techniques for deployment in various applications, and advances in signal processing. Innovations in special circuits, electronics and microelectronics are the key support for a large spectrum of applications. The conference is focusing on several complementary aspects and targets the advances in each on it: signal processing and electronics for high speed processing, micro-and nano-electronics, special electronics for implantable and wearable devices, sensor related electronics focusing on low energy consumption, and special applications domains of telemedicine and ehealth, bio-systems, navigation systems, automotive systems, home-oriented electronics, bio-systems, etc. These applications led to special des...

The FLuorescence EXplorer (FLEX) mission proposes to launch a satellite for the global monitoring... more The FLuorescence EXplorer (FLEX) mission proposes to launch a satellite for the global monitoring of steady-state chlorophyll fluorescence in terrestrial vegetation. Fluorescence is a sensitive probe of photosynthetic function in both healthy and physiologically perturbed vegetation, and a powerful non-invasive tool to track the status, resilience, and recovery of photochemical processes and moreover provides important information on overall photosynthetic performance with implications for related carbon sequestration. The early responsiveness of fluorescence to atmospheric, soil and plant water balance, as well as to atmospheric chemistry and human intervention in land usage makes it an obvious biological indicator in improving our understanding of Earth system dynamics. The amenability of fluorescence to remote, even space-based observation qualifies it to join the emerging suite of space-based technologies for Earth observation. FLEX would encompass a three-instrument array for m...

Image and Signal Processing for Remote Sensing XIV, 2008

Analog Integrated Circuits and Signal Processing, 2013

This special issue of ''Low-power circuit techniques'' in the Springer Journal of Analog Integrat... more This special issue of ''Low-power circuit techniques'' in the Springer Journal of Analog Integrated Circuits and Signal Processing is published with six papers, which are selected from presented papers at the 2012 International Conference on Analog VLSI Circuits (AVIC 2012). This conference is believed to be the only conference that bares the key word ''Analog VLSI'', and have accepted very wide range of papers concerning analog circuits. Among them, we called for papers related to low-power circuit techniques for this special issue. The Research Committee on Electronic Circuits of the Institute of Electrical Engineers of Japan (IEEJ) was sponsoring and cooperating with Analog Devices Inc.,

57th International Astronautical Congress, 2006

Sensors (Basel, Switzerland), 2021

One of the most powerful techniques to diagnose cardiovascular diseases is to analyze the electro... more One of the most powerful techniques to diagnose cardiovascular diseases is to analyze the electrocardiogram (ECG). To increase diagnostic sensitivity, the ECG might need to be acquired using an ambulatory system, as symptoms may occur during a patient’s daily life. In this paper, we propose using an ambulatory ECG (aECG) recording device with a low number of leads and then estimating the views that would have been obtained with a standard ECG location, reconstructing the complete Standard 12-Lead System, the most widely used system for diagnosis by cardiologists. Four approaches have been explored, including Linear Regression with ECG segmentation and Artificial Neural Networks (ANN). The best reconstruction algorithm is based on ANN, which reconstructs the actual ECG signal with high precision, as the results bring a high accuracy (RMS Error < 13 μV and CC > 99.7%) for the set of patients analyzed in this paper. This study supports the hypothesis that it is possible to recons...

The reaction begins in the amygdala, which triggers a neural response in the hypothalamus. The in... more The reaction begins in the amygdala, which triggers a neural response in the hypothalamus. The initial reaction is followed by activation of the pituitary gland and secretion of the ACTH hormone. The adrenal gland is activated almost simultaneously and releases the epinephrine hormone. The release of chemical messengers results in the production of the cortisol hormone, which increases blood pressure and blood sugar, and suppresses the immune system. The initial response and subsequent reactions are triggered in an effort to boost energy. This boost of energy is activated by epinephrine binding to liver cells and the subsequent production of glucose. Additionally, the circulation of cortisol functions to turn fatty acids into available energy, which prepares muscles throughout the body to respond. Catecholamine hormones, such as adrenaline (epinephrine) or noradrenaline (norepinephrine), facilitate immediate physical reactions associated with a preparation for violent muscular action.

This paper presents a methodology that faces the problem of detecting clouds in multispectral ima... more This paper presents a methodology that faces the problem of detecting clouds in multispectral images acquired by sensors working in the VNIR range. The method is capable of detecting clouds accurately providing probability and cloud abundance rather than flags. For this purpose, the method exploits the special characteristics of the PROBA/CHRIS instrument, such as the high number of spectral bands, the spatial resolution, and the specific band locations. Performance of the proposed algorithm is tested on six CHRIS images, which represent scenarios with different characteristics. Results demonstrate that the proposed algorithm yields good results even classifying difficult cloud pixels, especially thin cirrus clouds and clouds over ice/snow, and provides a better description of detected clouds.

En el presente estudio se muestra una comparativa de diferentes algoritmos de extraccion de endme... more En el presente estudio se muestra una comparativa de diferentes algoritmos de extraccion de endmembers aplicados a la descripcion y caracterizacion de nubes en imagenes de CHRIS/Proba. Primero se efectua un preprocesado de los datos para reducir los errores de drop-out noise y vertical stripping, despues se obtienen los pixeles “puros” o endmembers de la imagen mediante dos algoritmos automaticos estandar: Automated Target Generation Process (ATGP) y Automated Morphological Endmember Extraction (AMEE). Con los endmembers obtenidos se realiza una analisis de mezclas espectrales (SMA) lineal que proporciona mapas que indican tanto la presencia de nubes como la abundancia en cada pixel.

Analog Integrated Circuits and Signal Processing, 2014

Proceedings of Spie the International Society For Optical Engineering, Oct 1, 2008

Identification of land cover types is one of the most critical activities in remote sensing. Nowa... more Identification of land cover types is one of the most critical activities in remote sensing. Nowadays, managing land resources by using remote sensing techniques is becoming a common procedure to speed up the process while reducing costs. However, data analysis procedures should satisfy the accuracy figures demanded by institutions and governments for further administrative actions. This paper presents a methodological scheme to update the citrus Geographical Information Systems (GIS) of the Comunidad Valenciana autonomous region, Spain). The proposed approach introduces a multi-stage automatic scheme to reduce visual photointerpretation and ground validation tasks. First, an object-oriented feature extraction process is carried out for each cadastral parcel from very high spatial resolution (VHR) images (0.5m) acquired in the visible and near infrared. Next, several automatic classifiers (decision trees, multilayer perceptron, and support vector machines) are trained and combined to improve the final accuracy of the results. The proposed strategy fulfills the high accuracy demanded by policy makers by means of combining automatic classification methods with visual photointerpretation available resources. A level of confidence based on the agreement between classifiers allows us an effective management by fixing the quantity of parcels to be reviewed. The proposed methodology can be applied to similar problems and applications.

This paper proposes some useful modications to the Expanded Range Approximation (ERA) learning al... more This paper proposes some useful modications to the Expanded Range Approximation (ERA) learning algorithm. In channel equalisation, it is a common practise to recover the original signal using an articial neural network. The ERA algorithm is an alternative to the usual backpropagation algorithm that mitigates the eect of local minima during the training process. In the basis of ERA, we propose a soft-based proling of the homotopy parameter in order to avoid local minima in the error surface more ecien tly than in ERA. We use three specic membership functions that allow to control the smoothness of the learning process, yielding better results and lower computational cost. K e y w o r d s: articial neural networks, learning algorithms, soft computing, channel equalisation