Search results for "ADC"
showing 10 items of 179 documents
The model for public television and the young audience’s expectations. Differences between Great Britain and Spain in the perception of qualities and…
2017
Public service media (PSM) are in crisis throughout Europe. As a scenario for research, the two extremes of the background have been chosen: the first, BBC, is at the heart of media system, has become a model for the others and has just finished the particularly delicate challenge of renewal the fundamental law that is to rule over the next ten years; the second is on the periphery of public television, and in the extreme circumstances in Spain that have driven some of the television corporations to extinction, such as Canal 9 -Radiotelevisió Valenciana (RTVV). Using a method based on the use of semi-structured interviews and Delphi, the conception of these media models among their respecti…
“Vendor-Affected” WLAN experimental results: A Pandora’s Box?
2008
Experimental results are typically envisioned as the ultimate validation reference for any theoretical and/or simulation modelling assumptions. However, in the case of Wireless LANs, the situation is not nearly as straightforward as it might seem. In this paper, we discuss to what (large) extent measurement results may depend on proprietary undocumented algorithms implemented in the vendor-specific card/driver employed. Specifically, we focus on the experimental study of IEEE 802.11 b/g outdoor links based on the widely used Atheros/MADWiFi card/driver pair. We show that unexpected performance divergences do emerge in two classes of comparative experiments run on a same outdoor link: broadc…
A topology for multiple generation system with doubly fed induction machines and indirect matrix converter.
2008
In this paper, a new topology for a grid connected generation system based on two double fed induction generators is presented The scheme uses an indirect matrix converter consisting on an input rectifier, a three-to-two matrix converter which provides a DC voltage, and two voltage fed output converters. The input converter is connected to the grid and each of the output converters is connected to the rotor of the corresponding machine. The rotor currents of each generator are vector controlled and unity power factor operation at the indirect matrix converter input is considered. The duty cycles for the input converter are chosen in order to obtain maximum DC link voltage. The duty cycles f…
Difference temperature-to-time electronic interface based on a thermistor-to-generalized impedance converter
2010
Abstract In this work a difference temperature-to-time converter is shown using two thermistors working in a DC generalized impedance converter. Voltage drop in one of the thermistors depends on the temperature difference between them. This voltage is compared with a time varying exponential reference voltage obtaining a time interval at the output circuit with good linear dependence with respect to the input temperature difference. Experimental results are obtained showing a new generalized impedance converter application. The implemented circuit was characterized by a repeatability of 1.0%, a reproducibility of 4.5% and a relative accuracy of 1.3%.
Dynamic modelling of a quadratic DC/DC single-switch boost converter
2017
This manuscript proposes the analysis of a Quadratic Boost Converter (QBC) transformer-less single switch typology. The state space average dynamic model and a constrained state space average model taking into account the mono-directional components of the converter (diodes, switches) have been analyzed. The static gain expression taking into consideration the parasitic elements of the converter and the small-signal transfer function of the QBC typology under study has been obtained. A sensitivity analysis has shown a high variation of the gain versus duty-cycle and of the derivative gain versus parasitic parameters of the converter in the range of the duty-cycle from 0.6 to 0.8 which is ra…
Joint Resource Allocation and UAV Scheduling With Ground Radio Station Sleeping
2021
Applications of Unmanned aerial vehicles (UAVs) have advanced rapidly in recent years. The UAVs are used for a variety of applications, including surveillance, disaster management, precision agriculture, weather forecasting, etc. In near future, the growing number of UAV applications would necessitate densification of UAV infrastructure (ground radio station (GRS) and ground control station (GCS)) at the expense of increased energy consumption for UAV communications. Maximizing the energy efficiency of this UAV infrastructure is important. Motivated by this, we propose joint resource allocation and UAV scheduling with GRS sleeping (GRSS). Further, we propose the use of coordinated multi-poi…
Ann Radcliffe’s Gothic Romances and the Sea
2021
Biographical materials and the writer’s journals show that Ann Radcliffe had some personal knowledge of the sea and to some extent of sailing. She was also a lover of nature, an enthusiast of 17th -century landscapists, a connoisseur of Pre-Romantic poetry, who was also familiar with contemporary esthetic tastes and theories. In this context, the article analyzes seascapes, maritime and nautical references, motifs of storm and shipwreck in Radcliffe’s Gothic romances, including some poetical lines inspired by the sea with which The Mysteries of Udolpho is interspersed. The writer’s descriptions of the sea and her use of this element in her works are discussed in relation to her fictional ch…
Ambush Marketing in China: Counterbalancing Olympic Sponsorship Efforts
2008
This paper provides an empirical insight into the perception and use of ambush marketing on the People's Republic of China public television network CCTV5 (the official Olympic broadcaster), by examining the commercials used by various corporations during its coverage of the 2004 Olympic Games in Athens. A five-point categorization is presented to distinguish between various methods of ambushing. Despite the efforts of the Beijing government to fight ambush marketing ahead of its Olympic Games in 2008, the results demonstrate that concerns about the practice of ambush marketing in China must be taken seriously. An analysis of 40 commercial spots was carried out, based on China's 2002 Olympi…
Measurement of subpubic arch angle by three-dimensional transperineal ultrasound and impact on vaginal delivery
2015
Objectives To assess whether antepartum measurement of the subpubic arch angle (SPAA) as a parameter of the bony pelvic outlet can predict vaginal delivery. Methods Between January 2007 and June 2011, 625 nulliparous women with a singleton pregnancy were recruited from the antenatal clinic to be interviewed and have a four-dimensional transperineal ultrasound examination. Ultrasound examinations were performed between 34 and 36 weeks of gestation. Volume ultrasound data were saved for offline analysis, blinded against all other data. The SPAA was measured in the axial plane and logistic regression analysis was used to examine the association between SPAA and outcomes of vaginal delivery vs …
Multi-scale analysis of apparent diffusion coefficient (ADC) predicts cervical nodal status in patients with head and neck squamous cell carcinoma
2013
The study assess multi-scale diffusion parameters (median volumetric nodal region of interest values, inter-voxel histogram distributions, and intra-voxel diffusion heterogeneity as assessed by the stretched exponential model) as classifiers of nodal status in patients with head and neck squamous cell carcinoma (SCC). Low b value (0, 50, 100) derived nodal ADC (perfusion sensitive) was the key parameter facilitating discrimination of metastatic from benign nodes in patients with head and neck SCC. The stretched exponential derived α value together with histogram features of ADC provide an accurate decision tree model for classification of nodal disease.