Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Objetivando avaliar o comportamento das emissões de CO2 do solo em áreas mineradas do município de Santo Antônio de Pádua-RJ e sua correlação com a rizosfera, este presente estudo utilizou uma câmara fechada com sensor de infravermelho em três diferentes paisagens, a saber: A-1 (área reflorestada há 10 anos), A-2 (área desmatada) e A-3 (área em processo de recuperação). Em cada área foi instalada três cilindros para efeitos de repetição. O monitoramento foi realizado durante os meses representativos de cada estação do ano de 2013, sendo a análise realizada durante dois dias consecutivos. Concomitantemente as coletas de CO2 foram realizadas coletas de dados de temperatura e umidade do solo, sendo também avaliadas informações pedológicas através das análises de granulometria, porosidade, pH, carbono orgânico e matéria orgânica. Informações meteorológicas e microclimatológicas também foram extraídas através de uma estação meteorológica automática e através de sensores portáteis. Os resultados permitem concluir que existe uma variação sazonal dos fluxos de CO2, havendo uma tendência de máximos de emissão durante o verão e de mínimas durante o inverno, sendo o outono e a primavera marcados por valores medianos. A correlação das áreas entre os dois dias monitoramento indicam que as emissões foram semelhantes ao da análise em dia anterior, apresentando uma correlação significativa a 5% para A-1 e A-2 e de 1% para A-3. A-1 e A-2 apresentaram emissões de CO2 mais homogêneas que A-3, havendo, entretanto, um maior fluxo de CO2 durante o verão para todas as áreas. Os dados de MOS, COS e pH demonstraram não haver uma correlação direta com as emissões de CO2. Os dados de porosidade e densidade, porém, apontam para uma possível correlação com as menores emissões de CO2 em A-3 devido a menor porosidade e maior densidade de seus solos. A temperatura do solo foi a variável que mais se correlacionou com as emissões de CO2, havendo um índice igual a r =0,68 para A-1 e de r =0,74 para A-2, sendo que em A-3 esta correlação não foi significativa. A temperatura do ar demonstrou uma correlação somente na área descampada de A-2. No que se refere à correlação da umidade do solo não houve correlações diretas significativas, sendo que somente houve uma correlação negativa (r=-0,50) significativa a 5% em A-3 com a umidade do ar. O diagnóstico ambiental das áreas de monitoramento revela que estas possuem baixos indicadores de qualidade, sendo afetados também pela escassez hídrica da região durante oito meses do ano. A-1 apresenta os melhores indicadores biológicos, químicos e microclimáticos, seguidos por A-2 e A-3 que apresentam diversas deficiências e problemas em termos de estrutura e atividade biológica dos solos. Neste estudo permite-se concluir que áreas próximas, porém com características distintas podem produzir diferentes padrões de emissão de CO2, dificultando, portanto, estimativas globais de emissão de CO2. Os elementos mais associados às emissões de CO2 parecem estar relacionados à temperatura do solo e do ar, umidade do ar e estrutura do solo, havendo, entretanto, outros fatores que podem estar indiretamente relacionados e que exercem diferentes influências de acordo com o ambiente analisado. / Seeking evaluate the performance of CO2 emissions from soil in mined areas in the municipality of Saint Anthony of Padua - RJ and its correlation with the rhizosphere , the present study used a closed chamber with infrared sensor in three different landscapes , namely: A- 1 ( reforested area 10 years ago ) , a- 2 ( pasture) and A- 3 (area under recovery ) . In each area was installed three cylinders for the purpose of repetition. Monitoring was conducted during the months representing each season of the year 2013, with an analysis performed for two consecutive days. Simultaneously the analyses of temperature and soil moisture were performed, and also evaluated soil information by analyzing particle size , porosity, pH , organic carbon and organic matter information microclimatológicas and of weather were also extracted through sensors automatic and portable.The results indicate that there is a seasonal variation in CO2 fluxes , there is a trend of maximum emission during summer and minimum during winter , with autumn and spring marked by median values . The correlation among the areas two days indicate that monitoring emissions analysis were similar to the previous days, presenting a significant correlation to 5 % for A -1 and A -2 and A- 1 to 3 %. A- 1 and A- 2 had CO2 emissions more homogeneous than A- 3, there are, however, a greater flow of CO2 during the summer for all areas. MOS data, COS and pH showed no direct correlation with CO2 emissions. The porosity and density data, however, point to a possible correlation with the lowest CO2 emissions in A- 3 due to lower porosity and higher density of your soil. Soil temperature was the variable that was most associated with CO2 emissions, with an equal index for air = 0.68 A- 1 and r = 0.74 for A- 2, and A- 3 in this correlation was not significant. The air temperature showed a correlation only in the open area A- 2. With regard to the correlation of soil moisture no significant direct correlations, and only there was a significant negative correlation (r = -0.50) to 5 % in A- 3 with the humidity. The environmental assessment of the areas of monitoring shows that these have low quality indicators is also affected by water shortages in the region for eight months of the year. A- 1 shows the best biological, chemical and microclimatic indicators, followed by A-2 and A- 3 which have several deficiencies and problems in terms of structure and biological activity of soil. In this study, we conclude that nearby areas , but with distinct characteristics can produce different patterns of CO2 emission , thus hindering global estimates of CO2 emissions . Most elements associated CO2 emissions appear to be related to soil temperature and air temperature , humidity and soil , however , other factors that may be indirectly related and exert different influences according to the analyzed environment .

Este trabalho investiga a atuação do repórter de TV, profissional que, apesar de ser o principal narrador das histórias retratadas na televisão, se encontra à margem das pesquisas em telejornalismo. O objetivo foi mapear um estilo do repórter sob uma perspectiva histórica, buscando identificar diferenças e permanências nos elementos visuais da passagem, termo que no jargão jornalístico se refere ao momento em que o repórter aparece na reportagem. Como referencial teórico, utiliza-se o conceito de habitus de Bourdieu (2011), estudos de performance e dramaturgia de Goffman (1985), Coutinho (2012) e Gutmann (2012), entre outros autores, como Vizeu (2005), Benjamin (1996), Abreu e Lima (2010) e Mota (2001). Foram analisadas 72 reportagens das primeiras décadas do telejornalismo brasileiro e 73 reportagens contemporâneas, totalizando 145 passagens. Os resultados apontam um aumento no uso de movimentos de câmera, assim como o repórter também está se movimentando mais durante a passagem. O enquadramento mais utilizado é o plano americano, mas o plano geral, em que o repórter aparece de corpo inteiro, se tornou mais usual. O tempo médio da passagem aumentou, a formalidade do figurino está sendo deixada de lado e o grafismo surge como elemento visual auxiliar do repórter. O trabalho ainda reafirma a importância do papel do repórter de TV, figura que conduz a narrativa, confere credibilidade ao relato e estabelece um elo com a audiência. / This paper investigates the performance of the TV reporter, a professional that, despite being the main narrator of the stories on television, is excluded of researches in television journalism. The goal was to map a reporter style from a historical perspective in order to identify differences and continuities in the visual elements of the piece to camera, a term that in the journalistic jargon refers to the moment the reporter appears on TV. As a theoretical framework, we use the concept of habitus of Bourdieu (2011), performance and dramaturgy studies of Goffman (1985), Coutinho (2012) and Gutmann (2012), among others, as Vizeu (2005), Benjamin (1996), Abreu e Lima (2010) and Mota (2001). For this study, we analyzed 73 reports from the first decades of Brazilian television and 72 current reports, totalizing 145 pieces to camera. The results show an increase in the use of camera movements, and the reporter is also moving more during the piece to camera. The most widely used framework is the medium shot, but the wide shot, in which the reporter appears full body, became more common. The average time the reporter is displayed on the vídeo increased, the formality of clothing is being left aside and the graphics appears as a visual element helping the reporter. The study also reaffirms the importance of the TV reporter, that leads the narrative, gives credibility to the report and establishes a link with the audience.

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Due to the scarcity of frequency spectrum in view of the evolution of wireless communication technologies, the cognitive radio (CR) concept has been introduced to efficiently exploit the available spectrum. This concept consists in introducing unlicensed/secondary users (SU’s) in existing networks to share the spectrum of licensed/primary users (PU’s) without harming primary communications hence the name of “spectrum sharing” technique. We study in this dissertation, the capacity and the achievable rate of the secondary user within various communication settings. We, firstly, investigate the capacity of the (SU’s) at low power regime for Nakagami fading channels and present closed form of the capacity under various types of interference and/or power constraints. We explicitly characterize two regimes where either the interference constraint or the power constraint dictates the optimal power profile. Our framework also highlights the effects of different fading parameters on the secondary link ergodic capacity. Interestingly, we show that the low power regime analysis provides a specific insight on the capacity behavior of CR that has not been reported by previous studies. Next, we determine the spectral efficiency gain of an uplink CR Multi-Input Multi- Output (MIMO) system in which the SU is allowed to share the spectrum with the PU using a specific precoding scheme to communicate with a common receiver. Applied to Rayleigh fading channels, we show, through numerical results, that our proposed scheme enhances considerably the cognitive achievable rate. For instance, in case of a perfect detection of the PU signal, after applying Successive Interference Cancellation (SIC), the CR rate remains non-zero for high Signal to Noise Ratio (SNR) which is usually impossible when we only use space alignment technique. In addition, we show that the rate gain is proportional to the allowed interference threshold by providing a fixed rate even in the high SNR range. Finally, we study the impact of the broadcast approach and multi-layer coding on the throughput of CR systems for general fading channels. And we found that at the absence of the channel state information(CSI), we show that this improvement could be almost reached by 2-Layers coding. Then, we introduce a quantized CSI policy and highlight its improvement in terms of throughput before we study the rate when BA with quantized CSI is adopted. Numerical results show that the improvement of the additional layers is decreasing as the number of quantized regions increases.

An automatic system for supervision of the video and audio content in digital TV broadcasts was investigated in this master’s thesis project. The main goal is to find the best and most cost effective solution for Teracom to verify that the broadcast TV content as received by remote receivers is the same as that incoming to Teracom from content providers. Different solutions to this problem will be presented. The report begins with some background information about the Swedish terrestrial digital TV network and the MPEG-2 compression standard used to transport audio and video; including a description of the DVB Systems and Transport Stream protocol. It describes two current techniques for the supervision of the audio and video content, including an evaluation of these techniques. The first solution is to monitor the video and audio content either by detecting common errors such as frozen picture, visible artifacts, or by comparing the content from two different sources, i.e. a comparison of the output and the input content. The later could be done using video fingerprinting. The second solution monitors the video and audio content indirectly by analyzing the Transport Stream. This could be done either by comparing two Transport Streams to verify that the broadcast signal is identical to the received signal or by detecting common errors in the streams. Further two new potential solutions will be presented based on the research utilizing background knowledge of the MPEG-2 compression standard. The thesis ends with a summary with conclusions and evaluations of all four solutions and future work. / Ett system för automatisk övervakning av ljud- och bildinnehåll i digitala TV sändningar var undersökt i detta exjobb. Målet är att hitta bästa och mest kostnadseffektiva lösningen för Teracom för verifiering av TV innehållet som tas emot av fjärrmottagare är densamma som Teracom får från sina tjänsteleverantörer. Olika lösningar till detta problem blir presenterade. Presentationen startar med bakgrundsinformation om Sveriges marknät för digital TV och MPEG-2 komprimeringsstandarden som används för ljud- och bildsändningar. Den kommer att inkludera en kort beskrivning av DVB system och Transport ström protokoll. Två nuvarande tekniker för övervakningen av ljud- och bildinnehåll kommer att presenteras. Första lösningen handlar om att övervaka TV innehåller antigen genom att detektera vanligast förekommande fel såsom fryst bild, tydliga artefakter eller genom en jämförelse av innehållet från två olika källor, dvs. en jämförelse av ingångs och utgångssignal. Den senare kan åstadkommas genom att använda en så kallad video fingeravtryck. Andra lösningen övervakar ljud- och bildinnehåll indirekt genom att analyser Transport strömmen. Detta görs genom en jämförelse av två Transport strömmar för verifiering om signalen är densamma samt genom detektering av vanligast förekommande fel i strömmarna. Vidare, två nya potentiella lösningar kommer att presenteras med utgångspunkt från den backgrundskunskap om MPEG-2 komprimerings standard som getts. Presentationen avslutas med en sammanfattning och utvärdering av alla fyra lösningar och framtida arbeten.

Journalism plays an important role in our society. But what happens when a journalist decides to pursue a new profession? The loss of a journalist from a newsroom can have a significant impact, particularly when that journalist takes with them institutional knowledge and a history of the market. This study uses qualitative interviews with 12 former broadcast journalists to investigate what factors cause them to leave the field and what the implications are for the industry. Relying on burnout theory as a framework, this study reveals three key reasons broadcast journalists decided to walk away. First, they faced increasing demands including long or unconventional work hours, a tenuous work-life balance, difficult stories to cover, and doing more with fewer resources. Second, they endured difficult issues with management including unfulfilled promises, the increasing commercialization of news, unrealistic and unethical expectations, the consolidation of the industry, and a lack of appreciation. Third, they felt they were not adequately compensated. This study recommends more support and professional development for broadcast journalists, more cross-training opportunities, and improved financial compensation.

Dans de nombreux scénarios de communication sans fil multiutilisateurs, une bonne rétroaction est un ingrédient essentiel qui facilite l'amélioration des performances. Bien qu'étant utile, une rétroaction parfaite reste difficile et fastidieuse à obtenir. En considérant ce défi comme point de départ, le principal objet de cette thèse s'applique à adresser la question simple et pourtant insaisissable et fondamentale suivante: "Quel niveau de qualité de la rétroaction doit-on rechercher, et à quel moment faut-il effectuer un envoi pour atteindre une certaine performance en degrés de liberté (DoF)". La présente étude réussit à décrire de manière concise les régions DoF dans un cadre très général, correspondant à un processus général de rétroaction qui, à tout moment, peut ou non fournir des informations sur l'état du canal au niveau de l'émetteur (CSIT) - d'une qualité arbitraire - pour toute réalisation passée, actuelle ou future du canal. Sous des hypothèses standard , et en supposant par ailleurs que l'on dispose d'un CSIT suffisamment bien retardé, l'effet de la qualité du CSIT offert à tout moment, pour presque tout type de canaux est étudié de manière précise. Ceci est réalisé dans le cadre MISO-BC à deux utilisateurs, puis est directement étendu aux cas des MIMO-BC et MIMO-IC. En outre différents aspects de communication avec rétroaction limitée sont considérés, ainsi que l'aspect CSI global au niveau des récepteurs, et l'aspect diversité. En plus de fournir des limites théoriques et des nouveaux encodeurs et décodeurs, l'étude s'applique à obtenir une meilleure comprehension sur plusieurs questions pratiques d'intérêt capital dans le domaine. / In many multiuser wireless communications scenarios, good feedback is a crucial ingredient that facilitates improved performance. While being useful, perfect feedback is also hard and time-consuming to obtain. With this challenge as a starting point, the main work of thesis seeks to address the simple yet elusive and fundamental question of ``HOW MUCH QUALITY of feedback, AND WHEN, must one send to achieve a certain degrees-of-freedom (DoF) performance''. The work manages to concisely describe the DoF region in a very broad setting corresponding to a general feedback process that, at any point in time, may or may not provide channel state information at the transmitter (CSIT) - of some arbitrary quality - for any past, current or future channel (fading) realization. Under standard assumptions, and under the assumption of sufficiently good delayed CSIT, the work concisely captures the effect of the quality of CSIT offered at any time, about any channel. This was achieved for the two user MISO-BC, and was then immediately extended to the MIMO BC and MIMO IC settings. Further work also considers different aspects of communicating with limited feedback, such as the aspect of global CSI at receivers, and the aspect of diversity. In addition to the theoretical limits and novel encoders and decoders, the work applies towards gaining insights on many practical questions.

The study at hand intends to document patterns related to gender roles and depictions, dating, and sex which are unveiled in a sample of reality television programs.

In multiuser wireless networks, the base stations (BSs) rely on the channel state information (CSI) of the users to in order to perform user scheduling and downlink transmission. While the downlink channels can be easily estimated at all user terminals via a single broadcast, several key challenges are faced during uplink (feedback) transmission. Firstly, the noisy and fading feedback channels are usually unknown at the base station, and therefore, channel training is usually required from all users. Secondly, the amount of air-time required for feedback transmission grows linearly with the number of users. This domination of the network resources by feedback information leads to increased scheduling delay and outdated CSI at the BS. In this thesis, we tackle the above challenges and propose feedback reduction algorithms based on the theory of compressive sensing (CS). The proposed algorithms encompass both single and dual hop wireless networks, and; i) permit the BS to obtain CSI with acceptable recovery guarantees under substantially reduced feedback overhead, ii) are agnostic to the statistics of the feedback channels, and iii) utilize the apriori statistics of the additive noise to identify strong users. Numerical results show that the proposed algorithms are able to reduce the feedback overhead, improve detection at the BS, and achieve a sum-rate close to that obtained by noiseless dedicated feedback algorithms.