Search results for " Error."

Characterization of dual-polarization analogue radio over fiber fronthaul for LTE C-RAN architecture

2016

En este artículo se presentan los resultados de la medición ampliada de la radio analógica de doble polarización (DP) sobre fibra (RoF) en una arquitectura de red de acceso radio en la nube (C-RAN) de evolución a largo plazo (LTE). Esta técnica se propone para las conexiones de fibra entre las oficinas centrales y las estaciones base remotas. Se investigan varias longitudes de fibra óptica para determinar el mejor rendimiento del sistema en términos de magnitud de vector de error (EVM) y tasa de error de bit. La distancia máxima alcanzada para el caso de un ancho de banda LTE de 20 MHz es de 50 km, mostrando un valor de EVM admisible del 8,5% a la frecuencia de radio de 2,6 GHz cuando se ut…

SAVU: A Statistical Approach for Uncertain Data in Dynamics of Axially Moving Materials

2012

In physics and engineering problems, model input is never exact. The effect of small uncertainties on the solution is thus an important question. In this study, a direct statistical-visual approach to approximate the solution set is investigated in the context of axially moving materials. The multidimensional probability distribution for the input uncertainties is assumed known. It is considered as a deterministic object, which is then mapped through the model. The resulting probability density of the model output is visualized. The proposed system consists of three non-trivial parts, which are briefly discussed: a multidimensional sampler, a density estimator, and a high dynamic range (HDR…

Ligneous Cervicitis in a Woman With Plasminogen Deficiency Associated With an Atypical Form of Microglandular Hyperplasia

2013

A 19-yr-old woman with previously diagnosed clear cell adenocarcinoma was referred to the Charité for further treatment. Biopsies were taken from the cervix, the endometrium, pseudomembranes in the peritoneum, and sentinel lymph nodes. The morphologic picture of pseudomembranes and inflammation together with the provided information about plasminogen deficiency of the patients led to the hypothesis of ligneous cervicitis. The previously taken biopsies of the adenocarcinoma were reevaluated and showed a clear cell lesion. Further immunohistochemical examination with antibodies against p16, Ki67, CEA, and p53 could not prove its malignant character. As a result we diagnosed an atypical form o…

Fuzzy Variable Structure Control for Uncertain Systems with Disturbance

2012

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/105074 This paper focuses on the fuzzy variable structure control for uncertain systems with disturbance. Specifically, the fuzzy control is introduced to estimate the control disturbance, the switching control is included to compensate for the approximation error, and they possess the characteristic of simpleness in design and effectiveness in attenuating the control chattering. Some typical numerical examples are presented to demonstrate the effectiveness and advantage of the fuzzy variable structure controller proposed.

Investigation of data encryption impact on broadcasting visible light communications

2014

Este trabajo investiga el impacto de la encriptación y desencriptación de datos en un sistema de comunicaciones de luz visible (VLC) de difusión en interiores incrustado en la capa física. Se ha implementado el cifrado RSA para proporcionar una transmisión de datos segura en la capa física. El artículo muestra el rendimiento de la tasa de error de bits (BER) para los sistemas VLC seguros y no seguros (8 y 12 bits) para velocidades de datos de 2 y 12 Mbps. Para una BER de 10e-4 mostramos que hay penalizaciones de potencia de 2-4 dB con las VLC seguras. También se investiga el impacto de la longitud de la clave en la propagación del error y la penalización de potencia. EU Cost Action IC1101 T…

Worm-like artifacts in exfoliative cytology.

2006

The presence of worms in cytological smears is occasionally reported, although various other structures exist that may be confused with such parasites. We present eight worm-like artifacts observed in routine Papanicolaou smears. Recognition of these structures is important to avoid overvaluation or confusion with true worms. Diagn. Cytopathol. 2006;34:636–639. © 2006 Wiley–Liss, Inc.

Validation procedures in radiological diagnostic models. Neural network and logistic regression

1999

The objective of this paper is to compare the performance of two predictive radiological models, logistic regression (LR) and neural network (NN), with five different resampling methods. One hundred and sixty-seven patients with proven calvarial lesions as the only known disease were enrolled. Clinical and CT data were used for LR and NN models. Both models were developed with cross validation, leave-one-out and three different bootstrap algorithms. The final results of each model were compared with error rate and the area under receiver operating characteristic curves (Az). The neural network obtained statistically higher Az than LR with cross validation. The remaining resampling validatio…

Retrieval of vegetation height in rice fields using polarimetric SAR interferometry with TanDEM-X data

2017

This work presents for the first time a demonstration with satellite data of polarimetric SAR interferometry (PolInSAR) applied to the retrieval of vegetation height in rice fields. Three series of dual-pol interferometric SAR data acquired with large baselines (2–3 km) by the TanDEM-X system during its science phase (April–September 2015) are exploited. A novel inversion algorithm especially suited for rice fields cultivated in flooded soil is proposed and evaluated. The validation is carried out over three test sites located in geographically different areas: Sevilla (SW Spain), Valencia (E Spain), and Ipsala (W Turkey), in which different rice types are present. Results are obtained duri…

Non-fragile sliding mode control for flexible air-breathing hypersonic vehicles

2012

The non-fragile sliding mode tracking control design problem for a flexible air-breathing hypersonic vehicles (FAHVs) is investigated in this paper. A linearized model is constructed with respect to a trim point for the nonlinear, dynamically coupled simulation model of the FAHVs with external disturbance, then a reference model is designed and a tracking error model is proposed. An integral sliding surface is designed, and then the non-fragile H ∞ controller design problem for the sliding mode dynamics is discussed. sufficient condition is derived for the existence of such a controller in the presence of unmatched disturbance. A SMC law is derived to guarantee the reachability of the speci…

2021

Abstract Reliable patient-specific ventricular repolarization times (RTs) can identify regions of functional block or afterdepolarizations, indicating arrhythmogenic cardiac tissue and the risk of sudden cardiac death. Unipolar electrograms (UEs) record electric potentials, and the Wyatt method has been shown to be accurate for estimating RT from a UE. High-pass filtering is an important step in processing UEs, however, it is known to distort the T-wave phase of the UE, which may compromise the accuracy of the Wyatt method. The aim of this study was to examine the effects of high-pass filtering, and improve RT estimates derived from filtered UEs. We first generated a comprehensive set of UE…