Search results for "Computer network"
showing 10 items of 1634 documents
Implementation of algorithms forK shortest loopless paths
1986
Implementations of loopless k shortest path algorithms are examined. Efficient storage structures for a large number of paths are given. A fast algorithm for determining the shortest paths in Yen's method is developed. Timing experiments show that a hybrid of Clarke's and Yen's methods is generally the fastest, although not significantly. Using upper bounds for the lengths of paths essentially improves all methods.
Dualidad en la aljama. Propietarios de tierra y hombre de negocio musulmanes. El caso de la comarca valenciana de El Comtat (segunda mitad del siglo …
2014
El presente trabajo pretende estudiar las diferencias socioeconomicas que se generaron en el seno de las aljamas musulmanas valencianas durante el siglo XV. A diferencia de lo que frecuentemente ha mostrado la historiografia, las comunidades islamicas rurales no eran grupos homogeneos de campesinos sin tierras, sino que habia importantes jerarquias (diferencias) en su interior. Tomando como ejemplo el caso de la comarca de El Comtat, en la zona centro-sur del antiguo reino de Valencia, analizamos la dualidad social y economica de las aljamas a traves del estudio del mercado de la tierra y del mercado de productos agricolas. Todo ello nos permite descubrir una elite musulmana de propietarios…
Dipo : ciudad 'tartésico-turdetana' en el valle del Guadiana
2009
Los hallazgos de monedas de Dipo en el término de Guadajira, Badajoz, y el estudio territorial del Valle del Guadiana en época orientalizante han permitido localizar esta importante población de la antigua Lusitania. Su origen es una colonia tartésica, paralela y rival de Medellín-Conisturgis, pues ambas controlaban dos ramales paralelos de la 'Via de la Plata ' y la vía de Olisipo a Oretum, que unía todas las colonias periféricas del mundo tartesio septentrional.
An empirical evaluation of two natural hand interaction systems in augmented reality
2022
AbstractHuman-computer interaction based on hand gesture tracking is not uncommon in Augmented Reality. In fact, the most recent optical Augmented Reality devices include this type of natural interaction. However, due to hardware and system limitations, these devices, more often than not, settle for semi-natural interaction techniques, which may not always be appropriate for some of the tasks needed in Augmented Reality applications. For this reason, we compare two different optical Augmented Reality setups equipped with hand tracking. The first one is based on a Microsoft HoloLens (released in 2016) and the other one is based on a Magic Leap One (released more than two years later). Both d…
Perceptual adaptive insensitivity for support vector machine image coding.
2005
Support vector machine (SVM) learning has been recently proposed for image compression in the frequency domain using a constant epsilon-insensitivity zone by Robinson and Kecman. However, according to the statistical properties of natural images and the properties of human perception, a constant insensitivity makes sense in the spatial domain but it is certainly not a good option in a frequency domain. In fact, in their approach, they made a fixed low-pass assumption as the number of discrete cosine transform (DCT) coefficients to be used in the training was limited. This paper extends the work of Robinson and Kecman by proposing the use of adaptive insensitivity SVMs [2] for image coding u…
Los Estereotipos de género en las producciones audiovisuales: diseño y validación de la tabla de análisis EG_5x4
2022
Los productos culturales de la educación no formal, y en concreto los difundidos por televisión y plataformas streaming, incluidas no ficción y animación infantil, proponen entre sus figuraciones personajes estereotipados en su construcción de género. Según investigaciones previas, identificarlos y combatirlos favorece la erradicación de ideas sexistas relacionadas con violencias machistas. Por ello, el objetivo que se planteó fue diseñar y validar una tabla de análisis de estereotipos sexuales presentes en cualquier producto audiovisual. El proceso siguió un protocolo de 3 fases (Garrido et al., 2015): 1) Se revisó la literatura publicada, se extrajeron rasgos relacionados con estereotipos…
Vox and journalistic information: use and criticism of the media in the 2019 General Election campaigns
2022
The general elections held in 2019 gave Vox enough votes to enter the Spanish Parliament as the third most popular political party. The growing role of this radical right-wing party has revealed a complex relationship with the media. The objective of this study is to characterise the relationship between Vox and the media by analysing the party's electoral discourse using quantitative techniques – posts made on Facebook and Twitter (n = 224) – and qualitative techniques, exploring the framing used in the closing rallies of the campaign. References to the media dominated the messages Vox posted on Twitter during the November campaign, whose main purpose was to repost content previously broad…
Indoor localization using time difference of arrival with UWB signals and unsynchronized devices
2020
Abstract Indoor location using radio frequency (RF) signals has been traditionally focused mainly on RSSI and fingerprint techniques, because methods based on time of arrival (ToA) or time difference of arrival (TDoA) were not suitable for measuring short distances. However, the release of the IEEE 802.15.4a standard, the emergence of commercial ultra wide band (UWB) transceivers that are compliant to this norm and the integration of high frequency oscillators have permitted the design of more accurate indoor localization systems using the RF signal transmission time. In this paper, we propose an indoor localization system based on TDoA for UWB. The method implements an only one way transmi…
A study of LoRaWAN protocol performance for IoT applications in smart agriculture
2020
Abstract The use of Internet of Things (IoT) is becoming increasingly common in agribusiness to increase food production capacity for the expanding global population. Recently, low-power wide-area networks (LPWANs) have been used in the development of IoT applications that require low power consumption and low data transmission rates. LoRaWAN is considered the most suitable communication network for LPWANs for IoT applications in smart agriculture. In this paper, we present an in-depth study of the performance of the LoRaWAN communication network in the context of an IoT application for a pilot farm. We consider several scenarios and analyze simulation results by using Network Simulator 3. …
Design and performance evaluation of an hybrid reservation-polling MAC protocol for power-line communications
2003
This paper presents an hybrid reservation-polling MAC protocol able to effectively deal with the channel disturbances typical of Power-line communication systems. Channel access is controlled by a scheduler running on a centralized station. Fast retransmission of corrupted packets is employed to achieve high performance on Power-line channels characterized by frequent error bursts due to impulsive noise. The performance of our proposed mechanism are evaluated by means of simulation, for the more challenging case of time-sensitive traffic sources (voice calls). Results show that the system efficiency is virtually not affected by lightly to moderately disturbed PLC channel. Moreover, by sligh…