• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 220
  • 50
  • 24
  • 23
  • 20
  • 16
  • 10
  • 8
  • 6
  • 5
  • 4
  • 4
  • 3
  • 2
  • 2
  • Tagged with
  • 502
  • 107
  • 107
  • 79
  • 77
  • 73
  • 72
  • 59
  • 56
  • 51
  • 51
  • 48
  • 47
  • 46
  • 46
  • 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.
71

Americans in exile

Colagiovanni, Daniel January 1970 (has links)
Thesis (M.S.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / OBJECTIVES: "Americans in Exile," a two-part documentary series for radio is an endeavor to shed some light on a subject which has been shrouded in confusion and, in many cases, simplistic thinking: draft dodgers and deserters in Canada. [TRUNCATED] / 2031-01-01
72

Análise da disseminação de dados em redes FANET / Analysis of data dissemination in FANET networks

Pires, Rayner de Melo 22 March 2019 (has links)
Os veículos aéreos não tripulados (VANTs) vêm apresentando destaque crescente no setor aeronáutico mundial, tanto no desenvolvimento dos mesmos quanto nas diferentes aplicações desses veículos, devido ao seu grande potencial de utilização. Em muitas aplicações, a utilização de múltiplos VANTs apresenta várias vantagens sobre um VANT sozinho. No entanto, o agrupamento pode experimentar problemas inerentes à comunicação sem fio, podendo originar novos problemas como inviabilizar a coordenação e a execução cooperativa de uma missão, por exemplo. Em um cenário não colaborativo, VANTs com algum nível de autonomia e que partilhem do mesmo espaço aéreo também deverão ser capazes de trocar informações entre si, principalmente informações sobre posicionamento e rota de voo, e também estarão suscetíveis aos distúrbios da comunicação sem fio. Para balancear as vantagens e as desvantagens, esses robôs precisarão se comunicar cientes das restrições e utilizando a rede de modo otimizado, por meio da aplicação de algoritmos que equilibrem adequadamente técnicas de difusão de informações e técnicas de mitigação de retransmissões. Neste projeto de doutorado foi feita a investigação sobre o método de disseminação de dados, por meio de broadcasting, em uma rede móvel ad hoc entre VANTs, denominada Flying Ad hoc Networks (FANETs). FANETs são um novo paradigma que pode superar as restrições de missões de um único VANT. As FANETs são compostas por vários VANTs que cooperam para realizar alguma missão crítica (por exemplo, uma missão de busca e resgate). Para manter a coordenação, todos os VANTs devem continuamente enviar ou retransmitir mensagens através do canal sem fio para garantir que todos os membros da rede saibam o estado da rede. Geralmente, a troca de dados necessários para manter a sincronização da missão exige o uso de broadcast para que todos os membros da rede possam recebê-los. No entanto, quando essa troca de mensagens é feita arbitrariamente, isso pode causar o problema da tempestade de broadcast (BSP), levando o meio sem fio a um estado inoperante. Apesar de alguns esforços relatados na literatura para o provimento de técnicas gerais de mitigação do problema BSP, o desafio de agregar novas informações ou conhecimento a receptores que estejam voando, ao invés de apenas espalhar os dados na rede, tem recebido menos atenção. Nesta tese, além de demonstrar que o problema BSP intensifica a contenção de rede à medida que o número de VANTs aumenta, também foi criado um método que se prova mais eficiente que os existentes até então. Tal técnica, denominada de Algoritmo Baseado em Vizinhança Dinâmica para o Problema da Tempestade de Broadcast (DNA-BSP), foi desenvolvida e validada com base em experimentos de mundo real e em simulações computacionais. Ele pode mitigar o problema BSP, que é um desafio real nas FANETs, reduzindo a redundância de mensagens em mais de 98% e tornando a entrega de mensagens 99,5% mais rápida do que no cenário de flooding, superando as técnicas gerais de mitigação do BSP quando aplicado em FANETs. Os resultados detalhados neste texto também poderão orientar trabalhos futuros ao fornecer informações úteis para o planejamento e otimização de redes ad hoc móveis para VANTs. / Unmanned aerial vehicles (UAVs) have been showing increasing notoriety in the global aviation scene, both on their development and on the different applications for these vehicles, due to their high potential of use. In many applications, using multiple UAVs has several advantages over a single UAV. However, a cluster of UAVs may experience issues inherent to wireless communication, which may lead to new complications such as making mission coordination and cooperative execution impractible. In a non-collaborative scenario, UAVs with some level of autonomy which share the same airspace should also be able to exchange information among themselves, especially positioning and flight path information, and may also be susceptible to wireless communication disturbances. These robots have to use the network fairly and should communicate under restrictions, appropriately adjusting techniques that disseminate information and that mitigate broadcasts, in order to balance the advantages and disadvantages of being a group. This Ph.D. research investigates how broadcasting is used to disseminate data throughout ad hoc mobile networks between UAVs called Flying Ad hoc Networks (FANETs). FANETs are a new paradigm that can overcome the mission constraints of single UAVs. FANETs are composed of several UAVs that cooperate to accomplish a critical mission (e.g., hazardous area monitoring). Aiming to maintain UAVs coordination, all aircraft must continuously retransmit or relay messages through the wireless channel to assure that every member knows the FANET status. However, when this message exchange is done blindly, it may cause the broadcast storm problem (BSP), leading the wireless medium to a dysfunctional state. Despite some efforts reported in the literature for providing general techniques to mitigate the broadcast storm problem, the challenge of aggregating new information or knowledge to receivers, instead of just spreading the information in the network, has received less attention. In this research, it has been proved that the broadcast storm problem causes network contention as the number of UAVs increases, and the innovative Dynamic Neighborhood-based Algorithm for the Broadcast Storm Problem (DNA-BSP) has been provided as a countermeasure, which was developed and validated based on computer simulations and outdoor experiments. It can mitigate the broadcast storm problem, which is a real challenge in FANETs, reducing message redundancy in more than 98%, and making message delivery 99,5% faster than in flooding scenario, outperforming classical broadcast storm mitigation techniques when applied in FANETs. Our detailed results can also guide future researches and provide useful insights for engineers planning and optimizing mission-critical mobile ad hoc network with support of UAVs.
73

Quando o repórter aparece na TV : o corpo e a voz da notícia no telejornalismo brasileiro

Silva, Filipe Peixoto da January 2016 (has links)
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.
74

Enhancing network scalability by introducing mechanisms, architectures and protocols

Alasadi, Emad Younis January 2017 (has links)
In this thesis, three key issues that restrict networks from scaling up so as to be able to cope with the rapid increase in traffic are investigated and series of approaches are proposed and tested for overcoming them. Firstly, scalability limitations owing to the use of a broadcast mechanism in one collision domain are discussed. To address this matter, servers under software-defined network architectures for eliminating discovery messages (SSED) are designed in this thesis and a backbone of floodless packets in an SDN LAN network is introduced. SSED has an innovative mechanism for defining the relationship between the servers and SDN architecture. Experimental results, after constructing and applying an authentic testbed, verify that SSED has the ability to improve upon the scalability of the traditional mechanism in terms of the number of switches and hosts. This is achieved by removing broadcast packets from the data and control planes as well as offering a better response time. Secondly, the scalability restrictions from using routers and the default gateway mechanism are explained. In this thesis, multiple distributed subnets using SDN architecture and servers to eliminate router devices and the default gateway mechanism (MSSERD) are introduced, designed and implemented as the general backbone for scalable multiple LAN-based networks. MSSERD's proposed components handle address resolution protocol (ARP) discovery packets and general IP packets across different subnets. Moreover, a general view of the network is provided through a multi-subnets discovery protocol (MDP). A 23 computers testbed is built and the results verify that MSSERD scales up the number of subnets more than traditional approaches, enhances the efficiency significantly, especially with high load, improves performance 2.3 times over legacy mechanisms and substantially reduces complexity. Finally, most of the available distributed-based architectures for different domains are reviewed and the aggregation discovery mechanism analysed to establish their impact on network scalability. Subsequently, a general distributed-centralised architecture with open-level control plane (OLC) architecture and a dynamic discovery hierarchical protocol (DHP) is introduced to provide better scalability in an SDN network. OLC can scale up the network with high performance even during high traffic.
75

Multimodal News Summarization, Tracking and Annotation Incorporating Tensor Analysis of Memes

Tsai, Chun-Yu January 2017 (has links)
We demonstrate four novel multimodal methods for efficient video summarization and comprehensive cross-cultural news video understanding. First, For video quick browsing, we demonstrate a multimedia event recounting system. Based on nine people-oriented design principles, it summarizes YouTube-like videos into short visual segments (812sec) and textual words (less than 10 terms). In the 2013 Trecvid Multimedia Event Recounting competition, this system placed first in recognition time efficiency, while remaining above average in description accuracy. Secondly, we demonstrate the summarization of large amounts of online international news videos. In order to understand an international event such as Ebola virus, AirAsia Flight 8501 and Zika virus comprehensively, we present a novel and efficient constrained tensor factorization algorithm that first represents a video archive of multimedia news stories concerning a news event as a sparse tensor of order 4. The dimensions correspond to extracted visual memes, verbal tags, time periods, and cultures. The iterative algorithm approximately but accurately extracts coherent quad-clusters, each of which represents a significant summary of an important independent aspect of the news event. We give examples of quad-clusters extracted from tensors with at least 108 entries derived from international news coverage. We show the method is fast, can be tuned to give preferences to any subset of its four dimensions, and exceeds three existing methods in performance. Thirdly, noting that the co-occurrence of visual memes and tags in our summarization result is sparse, we show how to model cross-cultural visual meme influence based on normalized PageRank, which more accurately captures the rates at which visual memes are reposted in a specified time period in a specified culture. Lastly, we establish the correspondences of videos and text descriptions in different cultures by reliable visual cues, detect culture-specific tags for visual memes and then annotate videos in a cultural settings. Starting with any video with less text or no text in one culture (say, US), we select candidate annotations in the text of another culture (say, China) to annotate US video. Through analyzing the similarity of images annotated by those candidates, we can derive a set of proper tags from the viewpoints of another culture (China). We illustrate cultural-based annotation examples by segments of international news. We evaluate the generated tags by cross-cultural tag frequency, tag precision, and user studies.
76

Twitter and Radio News: A Dallas-Fort Worth Case Study

Lambert, Mark T 08 1900 (has links)
This study of radio news stations adds to the field of Twitter research into broadcasters' use of this social media microblogging platform; previous research has predominantly focused on television. This case study, based on a survey with numerous open-ended questions completed in face-to-face interviews, begins to fill in data on how Twitter is being used in major market radio station newsrooms. Limited in scope, this exploratory study used answers from seven members of two radio newsrooms in trying to find out if there were stated goals for tweets; if separate, unique content was being tweeted or was content tied to the stations' on-air product; how tweets seek to increase station listenership and/or increase station website traffic; what were the most frequently tweeted topics; what hyperlinks were included in tweets for internal or external web content; and were tweets personal and/or opinionated, or kept more professional with just factual material. From a strategic management theory standpoint, there is neither a stated plan nor goals sought with these newsrooms' use of Twitter. Unique tweet content includes sending out photos which add visuals to the pictureless world of radio news and live-tweeting of ongoing news events, while complementary content is promotional to push audience members to on-air or website products. There are no analytics in place to try to determine whether the stations' listenership or web traffic increases based on tweets. Promotional teases of upcoming on-air guest interviews or news content and/or web content are the most frequently tweeted topics. Hashtags rather than hyperlinks are more often included in the stations' tweets. News personnel stay away from expressing opinions, or being too personal in tweets, but remain more objective and professional by sticking to facts which is in step with the traditional role of journalists.
77

Personal Narratives of Health by TV Anchors and Reporters: Issues of Control Over Social Media and Professional Expression

January 2019 (has links)
abstract: Broadcast journalists often report on people dealing with illness or physical hardship, their difficulties and triumphs. But what happens when journalists personally experience those kinds of health-related issues? This study explores how 24 local and national on-air journalists share how they manage life with illness and hardship using personal narratives shared on their professional social media pages, detailing how the journalists navigate sharing a deeply personal experience while maintaining a professional journalistic persona. Thematic analysis found the journalists’ performed three acts when sharing personal health information in a public forum: they reported on their illness, they were transparent, and they justified their actions. Within the three themes a range of expression – from personal to professional – and influences over content were found, leading to the final overarching theme, implications and consequences on content creation. This dissertation finds a complicated struggle to maintain a professional self while acknowledging the urge to connect with others through a deeply personal experience. / Dissertation/Thesis / Doctoral Dissertation Journalism and Mass Communication 2019
78

UHF television in a small Iowa market, 1968

Newbrough, William Bruce 01 January 1969 (has links)
No description available.
79

STANDARD OPERATING PROCEDURES FOR THE TRAFFIC INVENTORY DEPARTMENT OF THE DISNEY ABC TELEVISION GROUP

Johnson, Matthew L 01 December 2015 (has links)
The Mack truck principle is the reason a Standard Operating Procedure (SOP) document is a good idea – so I was told by my boss in my early days working for Disney ABC Television Group. This principle is quite simple: if the one person who knows how to do the job walks out the door and is hit by a Mack truck, we have a problem; no one else knows how to do what that person did. And when it comes to television operations, that is a huge dilemma! Standard Operating Procedures is a document that lists the step-by-step process for completing tasks in order to, in this case, keep a network on the air. This document would be beneficial in cases of disaster recovery, but it might be just as useful for training new employees or for covering for someone who is out sick. There may be various reasons to go to the SOP, but they all have the same goal: to keep operations working to fulfill the business objective. An SOP for the operations of an entire network would likely fill at least one if not multiple books, so in order to keep this project manageable, I limited the development of the SOP to one department, Traffic Inventory, which is responsible for the commercial and promotional assets which are sold and scheduled to air on any of the Disney cable networks (Disney Channel, DisneyXD, and Disney Junior.) In order to develop an SOP, it was necessary to review the different software programs in use, and understand their purpose and application to the overall operations of the cable networks. This will be a “living” document, meaning updates and changes will be anticipated, requiring constant maintenance of the SOP in order to keep it up to the latest development. In an effort to make it truly useful, multiple screen captures are used, as this provides a more user-friendly tutorial and makes for a more effective “blueprint” to comprehend and follow. By having Standard Operating Procedures on hand, anyone in the department will be able to effectively follow the process for handling the commercial and promotional assets in an efficient manner, with minimal impact on the daily operation of the networks. This will then be a valuable document, helping the business to keep its commitment to both advertisers and viewers, without the fear of Mack trucks.
80

The policy and practice of community radio: localism versus nationalism in U.S. broadcasting

Stiegler, Zachary Joseph 01 May 2009 (has links)
While localism is a particularly important aspect of Congress' mandate that broadcasters serve "the public interest, convenience or necessity," the history of US radio broadcasting exhibits persistent tensions between nationalism and localism, which have intensified in recent decades. Current concerns about the loss of localism in US radio broadcasting invite us to reinterpret US radio history from a local perspective. This dissertation traces the tensions between localism and nationalism in US radio broadcasting through four forms of radio broadcasting constructed specifically to serve localism and the public interest: the 10-watt Class D license, full power public radio as typified by National Public Radio, the Low Power FM (LPFM) license established in 2000, and the controversial use of low power radio by religious broadcasters. The Class D license, US public radio, and LPFM all originated with the stated objective of serving the public in meaningful ways which commercial broadcasting cannot. Yet to date, each of these has failed to meet this goal, whether due to legislative action, organizational failure or conflict amongst broadcast entities. Further, each of these case studies illustrates the conflict between nationalism and localism ever-present in efforts to establish radio broadcasting services that adequately and meaningfully serve local publics. Through a critical-historical analysis of the tensions between nationalism and localism in US radio broadcasting, this dissertation offers an understanding for the reasons and implications of the continued failure of radio's ability to serve local communities in the United States. In doing so, I look to the failures of the past to suggest how we may revise the current LPFM license to effectively serve local publics.

Page generated in 0.0272 seconds