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1.
Sensors (Basel) ; 19(6)2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30897822

RESUMEN

Self-calibrated Acoustic Local Positioning Systems (ALPS) generally require a high consumption of hardware and software resources to obtain the user's position at an acceptable update rate. To address this limitation, this work proposes a self-calibrated ALPS based on a software/hardware co-design approach. This working architecture allows for efficient communications, signal processing tasks, and the running of the positioning algorithm on low-cost devices. This fact also enables the real-time system operation. The proposed system is composed of a minimum of four RF-synchronized active acoustic beacons, which emit spread-spectrum modulated signals to position an unlimited number of receiver nodes. Each receiver node estimates the beacons' position by means of an auto-calibration process and then computes its own position by means of a 3D multilateration algorithm. A set of experimental tests has been carried out where the feasibility of the proposed system is demonstrated. In these experiments, accuracies below 0.1 m are obtained in the determination of the receptor node position with respect to the set of previously-calibrated beacons.

2.
Sensors (Basel) ; 18(1)2017 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-29301211

RESUMEN

This work proposes the use of a hybrid acoustic and optical indoor positioning system for the accurate 3D positioning of Unmanned Aerial Vehicles (UAVs). The acoustic module of this system is based on a Time-Code Division Multiple Access (T-CDMA) scheme, where the sequential emission of five spread spectrum ultrasonic codes is performed to compute the horizontal vehicle position following a 2D multilateration procedure. The optical module is based on a Time-Of-Flight (TOF) camera that provides an initial estimation for the vehicle height. A recursive algorithm programmed on an external computer is then proposed to refine the estimated position. Experimental results show that the proposed system can increase the accuracy of a solely acoustic system by 70-80% in terms of positioning mean square error.

3.
Rev Peru Med Exp Salud Publica ; 30(2): 235-40, 2013 Apr.
Artículo en Español | MEDLINE | ID: mdl-23949508

RESUMEN

In order to establish the reference intervals (RIs) of peripheral blood lymphocyte subsets (PBL) in healthy adults in Lima (Peru), a cross-sectional study was conducted among blood donors taken in between 2011 and 2012. Based on the criteria obtained from the guidelines of the Clinical and Laboratory Standards Institute (CLSI C28-A3), 318 samples were processed, 61.9% (197/318) coming from male donors. For PBL count, a flow cytometer with a simple platform was used. The RIs are established for each PBL in adults based on sex with their respective reference limits and 90% confidence intervals. Differences were found in CD3+ percentage counts (p=0.001) and in CD3-CD56+ absolute (p=0.003) and percentage counts (p?0.001). The RIs found are different to those described in studies conducted in other countries due to the characteristics of the population and the study model.


Asunto(s)
Subgrupos Linfocitarios , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Perú , Valores de Referencia , Población Urbana , Adulto Joven
4.
Rev. peru. med. exp. salud publica ; 30(2): 235-240, abr.-jun. 2013. ilus, mapas, tab
Artículo en Español | LILACS | ID: lil-680988

RESUMEN

Con el objetivo de establecer los Intervalos de Referencia (InR) de las subpoblaciones linfocitarias (SPL) de sangre periférica en adultos sanos de Lima (Perú), se realizó un estudio transversal en donantes de sangre captados entre el 2011-2012. Siguiendo criterios basados en las directrices del Clinical and Laboratory Standards Institute (CLSI C28-A3), se procesaron 318 muestras, el 61,9% (197/318) de ellas procedentes de donantes de sexo masculino. Para el recuento de las SPL se empleó un citómetro de flujo de plataforma simple. Se establecieron los InR de cada SPL en personas adultas según sexo con sus respectivos límites de referencia y sus intervalos de confianza al 90%. Se encontraron diferencias en los recuentos porcentuales de CD3+ (p<0,01); y en los recuentos absolutos (p<0,01) y porcentuales (p=0,01) de CD3-CD56+. Los InR hallados son diferentes a los descritos en estudios realizados en otros países. Dichas diferencias se deben a las características de la población y al modelo de estudio.


In order to establish the reference intervals (RIs) of peripheral blood lymphocyte subsets (PBL) in healthy adults in Lima (Peru), a cross-sectional study was conducted among blood donors taken in between 2011 and 2012. Based on the criteria obtained from the guidelines of the Clinical and Laboratory Standards Institute (CLSI C28-A3), 318 samples were processed, 61.9% (197/318) coming from male donors. For PBL count, a flow cytometer with a simple platform was used. The RIs are established for each PBL in adults based on sex with their respective reference limits and 90% confidence intervals. Differences were found in CD3+ percentage counts (p=0.001) and in CD3-CD56+ absolute (p=0.003) and percentage counts (p?0.001). The RIs found are different to those described in studies conducted in other countries due to the characteristics of the population and the study model.


Asunto(s)
Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Subgrupos Linfocitarios , Estudios Transversales , Recuento de Linfocitos , Perú , Valores de Referencia , Población Urbana
5.
Rev. peru. med. exp. salud publica ; 30(2): 235-240, abr.- jun. 2013. tab
Artículo en Español | PERNAL | ID: pnc-15094

RESUMEN

Con el objetivo de establecer los Intervalos de Referencia (InR) de las subpoblaciones linfocitarias (SPL) de sangre periférica en adultos sanos de Lima (Perú), se realizó un estudio transversal en donantes de sangre captados entre el 2011-2012. Siguiendo criterios basados en las directrices del Clinical and Laboratory Standards Institute (CLSI C28-A3), se procesaron 318 muestras, el 61,9% (197/318) de ellas procedentes de donantes de sexo masculino. Para el recuento de las SPL se empleó un citómetro de flujo de plataforma simple. Se establecieron los InR de cada SPL en personas adultas según sexo con sus respectivos límites de referencia y sus intervalos de confianza al 90%. Se encontraron diferencias en los recuentos porcentuales de CD3+ (p<0,01); y en los recuentos absolutos (p<0,01) y porcentuales (p menor o igual 0,01) de CD3-CD56+. Los InR hallados son diferentes a los descritos en estudios realizados en otros países. Dichas diferencias se deben a las características de la población y al modelo de estudio. (AU)


In order to establish the reference intervals (RIs) of peripheral blood lymphocyte subsets (PBL) in healthy adults in Lima (Peru), a cross-sectional study was conducted among blood donors taken in between 2011 and 2012. Based on the criteria obtained from the guidelines of the Clinical and Laboratory Standards Institute (CLSI C28-A3), 318 samples were processed, 61.9% (197/318) coming from male donors. For PBL count, a flow cytometer with a simple platform was used. The RIs are established for each PBL in adults based on sex with their respective reference limits and 90% confidence intervals. Differences were found in CD3+ percentage counts (p=0.001) and in CD3-CD56+ absolute (p=0.003) and percentage counts (p<0.001). The RIs found are different to those described in studies conducted in other countries due to the characteristics of the population and the study model. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Subgrupos Linfocitarios , Citometría de Flujo , Valores de Referencia , Perú , Estudios Transversales
6.
Rev. peru. med. exp. salud publica ; 30(2): 235-240, abr.- jun. 2013. tab
Artículo en Español | PERNAL | ID: pnc-8488

RESUMEN

Con el objetivo de establecer los Intervalos de Referencia (InR) de las subpoblaciones linfocitarias (SPL) de sangre periférica en adultos sanos de Lima (Perú), se realizó un estudio transversal en donantes de sangre captados entre el 2011-2012. Siguiendo criterios basados en las directrices del Clinical and Laboratory Standards Institute (CLSI C28-A3), se procesaron 318 muestras, el 61,9% (197/318) de ellas procedentes de donantes de sexo masculino. Para el recuento de las SPL se empleó un citómetro de flujo de plataforma simple. Se establecieron los InR de cada SPL en personas adultas según sexo con sus respectivos límites de referencia y sus intervalos de confianza al 90%. Se encontraron diferencias en los recuentos porcentuales de CD3+ (p<0,01); y en los recuentos absolutos (p<0,01) y porcentuales (p menor o igual 0,01) de CD3-CD56+. Los InR hallados son diferentes a los descritos en estudios realizados en otros países. Dichas diferencias se deben a las características de la población y al modelo de estudio. (AU)


In order to establish the reference intervals (RIs) of peripheral blood lymphocyte subsets (PBL) in healthy adults in Lima (Peru), a cross-sectional study was conducted among blood donors taken in between 2011 and 2012. Based on the criteria obtained from the guidelines of the Clinical and Laboratory Standards Institute (CLSI C28-A3), 318 samples were processed, 61.9% (197/318) coming from male donors. For PBL count, a flow cytometer with a simple platform was used. The RIs are established for each PBL in adults based on sex with their respective reference limits and 90% confidence intervals. Differences were found in CD3+ percentage counts (p=0.001) and in CD3-CD56+ absolute (p=0.003) and percentage counts (p<0.001). The RIs found are different to those described in studies conducted in other countries due to the characteristics of the population and the study model. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Subgrupos Linfocitarios , Citometría de Flujo , Valores de Referencia , Perú , Estudios Transversales
7.
Sensors (Basel) ; 12(6): 8055-72, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22969387

RESUMEN

The aim of this work is to propose an alternative way for wine classification and prediction based on an electronic nose (e-nose) combined with Independent Component Analysis (ICA) as a dimensionality reduction technique, Partial Least Squares (PLS) to predict sensorial descriptors and Artificial Neural Networks (ANNs) for classification purpose. A total of 26 wines from different regions, varieties and elaboration processes have been analyzed with an e-nose and tasted by a sensory panel. Successful results have been obtained in most cases for prediction and classification.


Asunto(s)
Nariz Electrónica , Redes Neurales (Computación) , Análisis de Componente Principal , Vino/análisis , Técnicas Biosensibles , Análisis de los Mínimos Cuadrados , Procesamiento de Señales Asistido por Computador , Factores de Tiempo , Vino/clasificación
8.
Sensors (Basel) ; 11(11): 10765-84, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22346670

RESUMEN

This work analyses the effect of the receiver movement on the detection by pulse compression of different families of codes characterizing the emissions of an ultrasonic local positioning system. Three families of codes have been compared: Kasami, Complementary Sets of Sequences and Loosely Synchronous, considering in all cases three different lengths close to 64, 256 and 1,024 bits. This comparison is first carried out by using a system model in order to obtain a set of results that are then experimentally validated with the help of an electric slider that provides radial speeds up to 2 m/s. The performance of the codes under analysis has been characterized by means of the auto-correlation and cross-correlation bounds. The results derived from this study should be of interest to anyone performing matched filtering of ultrasonic signals with a moving emitter/receiver.

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