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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Las Radios Comunitarias y su influencia en el proceso de desarrollo local en las comunidades salvadoreñas

Aparicio Pacheco, Rafael Orlando 08 July 2021 (has links)
En este trabajo se analiza la influencia que la radio comunitaria crea en la población para motivarle a participar de actividades en busca del desarrollo de sus comunidades. Se presentan diferentes teorías donde los autores contribuyen al enriquecimiento del documento y al proceso de investigación. También, se enmarca en la obtención de datos cuali-cuantitativos, los que al final vendrán a dictaminar resultados apegados a los objetivos e hipótesis planteadas en el mismo, que vienen a dar como resultado un marco orientador del comportamiento tanto de los medios como de sus audiencias. Elementos científicos recabados durante el recorrido por siete emisoras, muestran información y participación del oyente, comportamiento de los directores de las emisoras y da un panorama general de la situación que se vive en los recónditos lugares desde donde transmiten estas radios. Los medios y las comunidades muestran su identidad, sus necesidades y realidades que se viven en entornos de pobreza. Al final se exponen los resultados, los que corroboran las hipótesis de investigación y se muestran conclusiones del estudio.
22

Graph Theoretic Approach to QoS Guaranteed Spectrum Allocation in Cognitive Radio Networks

Swami, Sameer January 2008 (has links)
No description available.
23

Field-Programmable Custom Computing Machines for DFT/FFT and DCT/DST Algorithms

Potluri, Uma Sadhvi January 2013 (has links)
No description available.
24

[en] (RE) MAKING COMMUNITY RADIOS: THE TENSION TO TRANSFORM FICTION IN HISTORY / [pt] (RE) FAZENDO RÁDIOS COMUNITÁRIAS: A TENSÃO EM TRANSFORMAR FICÇÃO EM HISTÓRIA

ERICA CRISTINA DA SILVA GOMES 18 September 2007 (has links)
[pt] Nesta pesquisa nos voltamos para as narrativas jornalísticas de algumas rádios comunitárias do Rio de Janeiro. Identificamos de que forma tais emissoras lidam com este gênero, levando em consideração o modo como são produzidas as mensagens. No âmbito comunitário, demos visibilidade para histórias locais e reunimos características que consideramos como possibilidades de reconfiguração do radiojornalismo tradicional, tais como: presença da subjetividade, existência de textos sonoros híbridos e maior liberdade em explorar a linguagem do veículo. Recontamos a trajetória do rádio no Brasil com o intuito de inserir e legitimar as emissoras comunitárias neste processo. Processo que revela dificuldades das emissoras comunitárias em relação às seguintes questões: obtenção da licença, repressões, interrupção de atividades e nomenclatura atribuída ao segmento. Por outro lado, mostramos a organização dos militantes do movimento, assim como, o interesse da mídia convencional nas produções das rádios comunitárias. Estas abordagens só se concretizaram porque estaríamos diante de um contexto de mudanças paradigmáticas. O esfacelamento do discurso da modernidade como hegemônico possibilitou a emergência de narrativas plurais que vieram à tona. Entre estas vozes, até então recalcadas, estão as narrativas jornalísticas das rádios comunitárias. / [en] In this search, we focused on the journalistic narratives of some community radios in Rio de Janeiro. We identified how these broadcasting stations deal with this type of media, paying attention to the way the messages are produced. In the community sphere, we gave visibility to local stories, and united characteristics that we consider as possibilities of reconfiguring the traditional radiojournalism, such as: the presence of subjectivity, the existence of hybrid sound texts and the greater freedom to explore the radio`s language. We tell the trajectory of radio in Brazil to insert and legitimate the community broadcasting stations involved in this process. And this process reveals the difficulties that these stations face in relation to some topics: acquiring the license, the problem of repression, the interruption of the activities and the nomenclature given to the segment. On the other hand, we showed the organization of people that fight for these radios, as well as the interest of the traditional media in the production of the community radios. This approach is real only because we are facing a context that is going through paradigmatic changes. The dissolution of the modern discourse as homogeneous gave space to the arising of plural narratives. Among these voices, until then quite, are the journalistic narratives of the community radios.
25

Comparison of Statistical Signal Processing and Machine Learning Algorithms as Applied to Cognitive Radios

Tiwari, Ayush January 2018 (has links)
No description available.
26

Les radios alternatives : l'exemple de Radio Ici et Maintenant / Alternatives radios : the example of Radio Ici et Maintenant

Poulain, Sebastien 02 July 2015 (has links)
Dans cette thèse, nous nous demandons comment les mouvements contreculturels ont trouvé de nouveaux lieux d’expression grâce à la plus grande accessibilité de l’audiovisuel, grâce aussi au combat des « radios libres ». Plus précisément, nous cherchons à savoir pourquoi et comment la société et l’audiovisuel français ont permis la constitution d’un média alternatif radiophonique comme Radio Ici et Maintenant (RIM) et comment cette radio a trouvé un modèle économique viable pour diffuser son idéologie. Nous verrons que l’existence et la persistance de RIM est due à la conjonction de deux phénomènes : d’une part la diminution du coût d’entrée dans la radiophonie grâce au développement et au combat des « radios libres » qui ont donné naissance aux radios associatives (avec leur modèle juridico-économique spécifique), et d’autre part la diminution du coût d’entrée dans le marché religieux avec le développement de la contreculture New Age française issue de la contreculture américaine, elle-même issue des pensées religieuses alternatives occidentales (liées à l’ésotérisme, au médiumnisme) et des religions orientales (l’hindouisme et le bouddhisme). Ainsi, le modèle juridico-économique spécifique des radios associatives a permis de faire vivre puis persister l’idéologie « radiolibriste » et New Age au sein de RIM. Mais ajoutons que ce modèle n’aurait pas été possible s’il n’avait pas été porté par des animateurs bénévoles, des invités militants et des auditeurs actifs dont nous analysons ici le profil sociologique. L’intérêt scientifique de ce sujet provient du fait qu’il s’agit principalement d’étudier RIM qui est une ancienne « radio libre ». Elle a été l’une des radios les plus importantes au sein du mouvement. C’est la plus ancienne des radios locales privées parisiennes. C’est aujourd’hui une radio associative de catégorie A. Cette catégorie correspond à un grand nombre de radios (environ 600), mais celles-ci sont peu étudiées. Enfin, c’est une radio New Age et l’un des seuls médias audiovisuels français New Age. Croisant histoire et sociologie du religieux, des médias, de la communication, de la politique, des sciences, cette thèse repose sur une écoute assidue, sur de nombreux entretiens et discussions informelles, sur l’étude de différents fonds d’archives (papier, audio, numérique) et sur de nombreuses observations de type ethnographique. Nous donnons dans une première partie les outils scientifiques pour pouvoir analyser ce phénomène. Nous verrons ensuite dans quel contexte historique, radiophonique, économique, social, juridique et politique RIM fait son apparition et continue d’exister aujourd’hui. Enfin, nous nous focalisons sur le modèle radiophonique proposé, et sur les acteurs de cette radio. / In this thesis, we wonder how countercultural movement found new places of expression through the increased accessibility of audiovisual, thanks to "free radio" fight. Specifically, we want to know why and how society and the French media have enabled the establishment of an alternative media like Radio Ici et Maintenant (RIM) and how this radio has found a viable business model to spread its ideology. We shall see that the existence and persistence of RIM is due to the combination of two factors: firstly the reduction in the cost of entry into the radio broadcasting through the development and struggle of "free radio" that gave birth to associative radios (with their specific legal and economic model) and also the decrease in the cost of entering the religious market with the development of the French New Age counterculture issue of the American counterculture, itself the result of religious thoughts Western alternatives (related to the esoteric, the mediumship) and Eastern religions (Hinduism and Buddhism). Thus, the specific legal and economic model of associative radios allowed to live and persist "radiolibriste" and New Age ideology within RIM. But add that this model would not have been possible if it had not been worn by volunteer facilitators, invited activists and active listeners which we analyze the sociological profile. The scientific interest of this subject is the fact that it is mainly to study RIM which is an old "free radio". She was one of the most important radio stations in the movement. It is the oldest Parisian private local radio station. Today, it is a community radio (category A). This category corresponds to a large number of radio stations (about 600), but these are little studied. Finally, this is a New Age radio and one of the only French audiovisual media New Age. Crossing history and sociology of religion, media, communication, politics, science, this thesis is based on a constant listening, on numerous interviews and informal discussions on the study of different archives (paper, audio, digital) and numerous ethnographic observations. We give in the first part scientific tools to analyze this phenomenon. We will then see in which historical, radio, economic, social, legal and political context RIM appeared and continues to exist today. Finally, we focus on the proposed radio model and the actors of this radio.
27

Integrated, Dynamically Adaptive Supplies for Linear RF Power Amplifiers in Portable Applications

Sahu, Biranchinath 19 November 2004 (has links)
Energy-efficient radio frequency (RF) power amplifiers (PAs) are critical and paramount to achieve longer battery life in state-of-the-art portable systems because they typically determine and dominate the power consumption of such devices. In this dissertation, a high-efficiency, linear RF PA with a dynamically adaptive supply and bias current control for code division multiple access (CDMA) and wideband CDMA (WCDMA) is conceived, simulated, and experimentally demonstrated with a discrete PCB-level design and in integrated circuit (IC) form. The PA efficiency is improved by dynamically adjusting both its supply voltage and bias current, there by minimizing its quiescent power dissipation. The PA supply voltage is derived from the battery by a noninverting, synchronous buck-boost switching regulator because of its flexible functionality and high efficiency. Adjusting the PA supply voltage and bias current by tracking the output power, instead of following the complete envelope in large baseband bandwidth wireless applications, is achieved by a converter with a lower switching frequency and consequently higher light-load efficiency, which translates to prolonged battery life. A discrete PCB-level prototype of the proposed system with 915 MHz center frequency, CDMA IS-95 signal having 27-dBm peak-output power resulted in more than four times improvement in the average efficiency compared to a fixed-supply class-AB PA while meeting the required performance specifications. In the IC solution fabricated in AMIs 0.5-micron CMOS process through MOSIS, a dual-mode, buck-boost converter with pulse-width modulation (PWM) control for high power and pulse-frequency modulation (PFM) for low power is designed and implemented to improve the PA efficiency during active and standby operation, respectively. The performance of the dynamically adaptive supply and bias control IC was validated by realizing a 25-dBm, 1.96 GHz center frequency, WCDMA PA over an input supply range of 1.4 4.2 V. The PA with dual-mode power supply and bias control IC showed an average-efficiency improvement of seven times compared to a fixed-supply class-AB PA, which translates to five times improvement in battery life assuming the PA is active for 2 % of the total time and in standby mode otherwise.
28

Capturing Believers: American International Radio, Religion, and Reception, 1931-1975

Stoneman, Timothy H. B. 29 November 2005 (has links)
Capturing Believers provides a history of the reception of American conservative evangelical missionary broadcasting from its inception in 1931 through the rise of the commercial era in 1970. The dissertation narrates accounts of two major Protestant stations, HCJB and ELWA, located in Ecuador and Liberia, respectively, as well as the U.S.-based project to build a custom transistor radio for the mission field. Employing a case-study approach, the thesis demonstrates the innovativeness of religious broadcasters who formulated a range of pragmatic responses to the drastic shortage of receiving sets in the southern hemisphere, including the use of social convention and the development of pretuned receiver technology. Missionary stations imported not only radios, but a constellation of American values into host countries through their reception activities. Overall, officials employed creative methods to construct a particular type of listener experience known as radio capture, characterized by regular listening in a domestic setting. By penetrating into the home or village and exposing listeners to proprietary broadcasts on a continual, even daily, basis, missionary receiver programs legitimized American conservative evangelicalism abroad and sowed seeds for a widespread revival of Protestantism in Latin America and Africa after 1970.
29

Export marketing of radios by selected manufacturers in Hong Kong.

January 1976 (has links)
Kwan Yin-Ping. / Thesis (M.B.A.)--Chinese University of Hong Kong. / Bibliography: leaves 96-97.
30

Cognitive Radio Connectivity for Railway Transportation Networks

Gill, Kuldeep S 22 January 2018 (has links)
Reliable wireless networks for high speed trains require a significant amount of data communications for enabling safety features such as train collision avoidance and railway management. Cognitive radio integrates heterogeneous wireless networks that will be deployed in order to achieve intelligent communications in future railway systems. One of the primary technical challenges in achieving reliable communications for railways is the handling of high mobility environments involving trains, which includes significant Doppler shifts in the transmission as well as severe fading scenarios that makes it difficult to estimate wireless spectrum utilization. This thesis has two primary contributions: (1) The creation of a Heterogeneous Cooperative Spectrum Sensing (CSS) prototype system, and (2) the derivation of a Long Term Evolution for Railways (LTE-R) system performance analysis. The Heterogeneous CSS prototype system was implemented using Software-Defined Radios (SDRs) possessing different radio configurations. Both soft and hard-data fusion schemes were used in order to compare the signal source detection performance in real-time fading scenarios. For future smart railways, one proposed solution for enabling greater connectivity is to access underutilized spectrum as a secondary user via the dynamic spectrum access (DSA) paradigm. Since it will be challenging to obtain an accurate estimate of incumbent users via a single-sensor system within a real-world fading environment, the proposed cooperative spectrum sensing approach is employed instead since it can mitigate the effects of multipath and shadowing by utilizing the spatial and temporal diversity of a multiple radio network. Regarding the LTE-R contribution of this thesis, the performance analysis of high speed trains (HSTs) in tunnel environments would provide valuable insights with respect to the smart railway systems operating in high mobility scenarios in drastically impaired channels.

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