Search results for "spread"
showing 10 items of 292 documents
UWB Channel Measurements for Measures for Hand-Portable and Wearable Devices
2007
On-body UWB signal propagation is analyzed for propagation channels surrounding the body in an usual office environment for an application requiring the transmission of signals recorded from the head to a device such as a mobile phone or a PDA carried by the subject or also from the transmitter on the head to other devices located along the body. For the study, measurements of the frequency response by means of a VNA (Vector Network Analyzer) are performed at 2001 discrete frequency points in the 3 to 6 GHz range. Channel estimation parameters, such as mean excess delay, delay spread and path loss are obtained. Results show that for the transmitter located on top of the head best average pe…
The Nexus between Sovereign CDS and Stock Market Volatility: New Evidence
2021
This paper extends the studies published to date by performing an analysis of the causal relationships between sovereign CDS spreads and the estimated conditional volatility of stock indices. This estimation is performed using a vector autoregressive model (VAR) and dynamically applying the Granger causality test. The conditional volatility of the stock market has been obtained through various univariate GARCH models. This methodology allows us to study the information transmissions, both unidirectional and bidirectional, that occur between CDS spreads and stock volatility between 2004 and 2020. We conclude that CDS spread returns cause (in the Granger sense) conditional stock volatility, m…
Interference Cancellation for LoRa Gateways and Impact on Network Capacity
2021
In this paper we propose LoRaSyNc (LoRa receiver with SyNchronization and Cancellation), a second generation LoRa receiver that implements Successive Interference Cancellation (SIC) and time synchronization to improve the performance of LoRa gateways. Indeed, the chirp spread spectrum modulation employed in LoRa experiences very high capture probability, and cancelling the strongest signal in case of collisions can significantly improve the cell capacity. An important feature of LoRaSyNc is the ability to track the frequency and clock drifts between the transmitter and receiver, during the whole demodulation of the interfered frame. Due to the use of low-cost oscillators on end-devices, a s…
Heavy metals in coastal water systems. A case study from the northwestern Gulf of Thailand.
2005
A geochemical survey of the northwestern part of the Thailand Gulf (Inner Gulf) was carried out in order to define concentrations and distribution patterns of selected heavy metals (V, Cr, Co, Ni, Cu, Zn, and U) in the coastal system and estuarine area of the Mae Klong river. The results indicate the presence of two different sources of heavy metals in the studied environment and allowed us to identify a lithogenic component that significantly influences the composition of coastal waters and suspended particulate matter (SPM). Comparison of the normalized heavy metals concentrations both in the studied samples and in those reported for the Sn–W ores present in the surrounding areas suggests…
Sclerochronological evidence of pronounced seasonality from the late Pliocene of the southern North Sea basin and its implications
2022
Oxygen isotope (δ18O) sclerochronology of benthic marine molluscs provides a means of reconstructing the seasonal range in seafloor temperature, subject to use of an appropriate equation relating shell δ18O to temperature and water δ18O, a reasonably accurate estimation of water δ18O, and due consideration of growth-rate effects. Taking these factors into account, δ18O data from late Pliocene bivalves of the southern North Sea basin (Belgium and the Netherlands) indicate a seasonal seafloor range a little smaller than now in the area. Microgrowth-increment data from Aequipecten opercularis, together with the species composition of the bivalve assemblage and aspects of preservation, suggest …
Cost-distance defined by a topological function of landscape
2008
International audience; Distance is a basic concept in the domain of animal species motion. Cost distances, rather than Euclidian distances, are more and more used in order to have a more realistic measure, on the basis of resistance values assigned to each landscape class. We propose here a method to compute resistance values by using topological functions of landscape, i.e. by taking account of the proximity of habitat/non-habitat edges, with continuous functions. An example is given when comparing cost distances and the propagation of water vole in the massif of Jura (France). The comparison with usual cost distances gives information about the ecological assumptions. The results show al…
Essays On European Natural Gas Market
2018
La presente tesis ha cubierto diferentes aspectos de los mercados europeos del gas natural y la electricidad, en particular algunas propiedades que afectan a la efectividad de la cobertura, como la estacionalidad en varianza y en precios. Asimismo, se ha realizado un estudio de la prima de riesgo del gas natural, su relación con las variables de riesgo y su descomposición en una prima de riesgo de reinversión o ‘rollover’ y una prima de ‘preferencia por liquidez’ relacionada con el plazo. La tesis se compone de tres capítulos: el Capítulo I estudia la estacionalidad en los precios y la volatilidad y cómo mejora la efectividad de la cobertura teniendo en cuenta dicha estacionalidad; el Capít…
¿SE PUEDE MEDIR LA NEGOCIACIÓN INFORMADA?: UNA REVISIÓN DE LA METODOLOGÍA BASADA EN LAS COVARIANZAS DE LAS SERIES DE PRECIOS / CAN WE MEASURE THE INS…
2009
El desarrollo en los modelos teóricos de microestructura ha motivado la aparición de un grupo de trabajos encaminado al estudio empírico de los costes de transacción y sus componentes dada la importancia que han tenido los mismos en el estudio del funcionamiento de los mercados y la comparación entre éstos así como sus numerosas aplicaciones en campos afines (finanzas corporativas, eficiencia de los mercados, etc.). Por otra parte, la contrastación empírica de los distintos modelos establecidos muestra resultados claramente dispares. Por ello, el objetivo de nuestro trabajo es analizar con detalle y en conjunto dichos modelos centrándonos en un grupo con características muy similares. Concr…
Universidad Politécnica Radiotelevisión. Creación y primera etapa (2000-2008)
2012
En el artículo se trata la historia de los canales UPVRadio y Universidad Politécnica Televisión desde el año 2000 a 2008, incluyendo el proceso de estudio, diseño y puesta en marcha de ambos y una descripción de los objetivos, el modelo de gestión, la plantilla, los canales de emisión, la programación, la audiencia y las fuentes de financiación alternativa en el régimen permanente. Se comenta también la infraestructura de soporte de ambos canales, con apartados para las dependencias de la cadena, el equipamiento de la radio y el de la televisión. The article narrates the story of UPVRadio and Universidad Politecnica Television University from 2000 to 2008, including the process of study, d…
Extranodal extension of nodal metastasis is the main prognostic moderator in squamous cell carcinoma of the esophagus after neoadjuvant chemoradiothe…
2017
Several studies, including comprehensive systematic reviews with meta-analyses of our group of research, have demonstrated the negative prognostic impact of the extranodal extension of nodal metastasis (ENE) in different cancer types, including squamous cell carcinoma (SCC) of the vulva, of the penis and of head and neck, as well as in tumors of the digestive and genitourinary systems, in thyroid cancer and others (1-17).