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A interceptação de comunicação entre pessoas presentes como meio de investigação de prova no direito processual penal brasileiro; The interception of communications between present people as means of investigation of evidence in the Brazilian criminal procedural law.

Arantes Filho, Marcio Geraldo Britto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 29/04/2011 PT
Relevância na Pesquisa
36.45%
As comunicações entre pessoas presentes são tuteladas na Constituição brasileira, como decorrência da liberdade de manifestação do pensamento, do direito à intimidade e à vida privada, da inviolabilidade do domicílio e do direito a não autoincriminação. Embora sejam constitucionalmente tuteladas, as comunicações entre pessoas presentes podem ser restringidas, desde que sejam observadas as exigências de reserva de lei, de reserva de jurisdição e de proporcionalidade. A interceptação de comunicação entre pessoas presentes é meio de investigação de prova, que, por meio de restrição a direitos e garantias fundamentais, visa a descoberta de fontes de prova para a persecução penal. Trata-se de instrumento processual que consiste em atividade de captação e de registro de comunicação entre pessoas presentes de caráter reservado, por um terceiro, com o emprego de meios técnicos, utilizados em operação oculta e simultânea à comunicação, sem o conhecimento dos interlocutores ou com o conhecimento de um ou de alguns deles. A interceptação domiciliar e a interceptação ambiental são espécies de interceptação de comunicação entre pessoas presentes. O objeto e o caráter insidioso desta modalidade de interceptação impõem a necessidade de uma disciplina jurídica autônoma...

Divulgação Científica em Assessorias de Comunicação : o caso da Fapesp; Scientific Outreach in Communications offices : the case of Fapesp

Leila Cristina Bonfietti Lima
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 04/08/2011 PT
Relevância na Pesquisa
36.42%
As instituições de pesquisa e agências de fomento estão cada vez mais conscientes sobre a importância da divulgação da produção científica brasileira para a formação de uma cultura científica no país. A formação de jornalistas especializados na cobertura de Ciência, Tecnologia e Inovação (C,T&I) e a profissionalização das assessorias de comunicação têm sido fundamentais para a ampliação e a melhoria da qualidade da divulgação científica nos meios de comunicação. Este é o caso do setor de comunicação científica da Fundação de Amparo à Pesquisa do Estado de São Paulo (Fapesp), criado em 1995, e que desde então vem aprimorando suas atividades de divulgação e influenciando outras agências de fomento do país, pautadas pela sua experiência. Examinar o trabalho de comunicação integrada da Fapesp, cuja atuação tem contribuído na consolidação da imagem da Fundação é o objetivo principal deste trabalho. Trata-se de um Estudo de Caso, que utiliza a técnica da Análise de Conteúdo, com apoio da pesquisa bibliográfica, documental e entrevistas semi-estruturadas. A pesquisa é de natureza qualitativa, combinada com o método quantitativo para ilustrar algumas das informações. Os resultados da pesquisa indicam que a divulgação científica realizada pelo setor de comunicação da Fapesp está em processo contínuo de aperfeiçoamento e tem sido fundamental para a consolidação da imagem institucional. Os diferentes veículos e abordagens (revista Pesquisa Fapesp...

Enforcing flexibility in real-time wireless communications: A bandjacking enabled protocol

Bartolomeu, Paulo; Ferreira, Joaquim; Fonseca, José Alberto
Fonte: IEEE Publicador: IEEE
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
36.42%
Wireless communications are being applied in heterogeneous domains ranging from healthcare to industrial manufacturing. However, as wireless channels are highly unreliable, the support of applications having tight hard real-time and fault-tolerance requirements has been provided by dedicated wired communications. Recently, a technique named bandjacking has been evaluated as a feasible solution to mitigate the unreliability associated with wireless channels in contention-based communications environments. This paper builds on this technique to propose an FTT inspired protocol aiming to provide deterministic, reliable and flexible wireless communications.

Dependable wireless real-time communications for open environments; Comunicações sem-fios de tempo-real para ambientes abertos

Bartolomeu, Paulo Jorge de Campos
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
ENG
Relevância na Pesquisa
36.42%
Wireless communication technologies have become widely adopted, appearing in heterogeneous applications ranging from tracking victims, responders and equipments in disaster scenarios to machine health monitoring in networked manufacturing systems. Very often, applications demand a strictly bounded timing response, which, in distributed systems, is generally highly dependent on the performance of the underlying communication technology. These systems are said to have real-time timeliness requirements since data communication must be conducted within predefined temporal bounds, whose unfulfillment may compromise the correct behavior of the system and cause economic losses or endanger human lives. The potential adoption of wireless technologies for an increasingly broad range of application scenarios has made the operational requirements more complex and heterogeneous than before for wired technologies. On par with this trend, there is an increasing demand for the provision of cost-effective distributed systems with improved deployment, maintenance and adaptation features. These systems tend to require operational flexibility, which can only be ensured if the underlying communication technology provides both time and event triggered data transmission services while supporting on-line...

Broadband for Africa : Developing Backbone Communications Networks

Williams, Mark D. J.
Fonte: World Bank Publicador: World Bank
Relevância na Pesquisa
36.5%
Many countries in Sub-Saharan Africa see information and communication technology (ICT) as a necessary foundation for long-term economic development. While the region has been very successful in increasing access to basic voice communications, there has been no comparable improvement in broadband connectivity. In fact, the broadband access gap between Sub-Saharan Africa and the rest of the world is getting wider just as the gap in basic voice communications is getting smaller. Increasing access to broadband connectivity is therefore emerging as a high priority for policy makers across the continent. This book begins with a brief review of the ICT market and considers the extent of demand for broadband and the ICT services that high-capacity backbone networks make possible. This is followed by a review of the existing coverage of backbone networks in the region, a discussion of how this compares with other parts of the world, and an analysis of the possible explanations for the current pattern of network development. Finally...

Cambodia : Review of Government Information and Communications Technologies Policies and Investments

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
36.42%
Further, governments are using information and communication technologies (ICT) as tools to reduce transaction costs and processing time, and increase government revenues. Further, the potential to access public services at home or at a local Internet kiosk empowers citizens in rural areas, including women and minorities. Access to relevant public information on rights and benefits, inheritance and family laws, health care, and housing can be provided through the Internet or mobile phone which translates to easier access and less time than traveling to or queuing up at government departments. The Royal Government of Cambodia (the Government) has taken various initiatives regarding the streamlining of ICTs in administration functions and several core agencies have invested or are planning on investing in information systems, databases of various types, websites, communications networks, etc. However, this figure will be significantly higher when the cost for ICT components under sector projects, such as under education...

ICT Sector Policy Note for Panama : Enabling Inclusive Development through Information and Communications Technologies

World Bank
Fonte: Banco Mundial Publicador: Banco Mundial
EN_US
Relevância na Pesquisa
36.42%
The Government of Panama and the private sector recognize the importance of information and communications technology (ICT) as an enabler of national development. This ICT sector policy note seeks to identify opportunities and challenges for growth of the ICT sector in Panama, particularly on rural access to broadband services and on cybersecurity, and potential for spillover impacts across other sectors. It provides a brief overview of the ICT sector in Panama and outlines a series of strategic actions and recommendations aimed at leveraging ICT as an engine of growth by targeting connectivity infrastructure, policies, regulation, e-Services, public data, and skills. The report is organized as follows: section one presents ICT sector in the economy. Section two deals with offer for connectivity. Section three presents demand. Section four describes the sector status from the cybersecurity point of view. Based on these analyses, section five identifies challenges that are hindering the growth of the industry, and section six presents policy options to overcome them. Finally...

Extended Coverage for Public Safety and Critical Communications Using Multi-hop and D2D Communications

Babun, Leonardo
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
36.48%
In this thesis, we proposed the use of device-to-device (D2D) communications for extending the coverage area of active base stations, for public safety communications with partial coverage. A 3GPP standard compliant D2D system level simulator is developed for HetNets and public safety scenarios and used to evaluate the performance of D2D discovery and communications underlying cellular networks. For D2D discovery, the benefits of time-domain inter-cell interference coordi- nation (ICIC) approaches by using almost blank subframes were evaluated. Also, the use of multi-hop is proposed to improve, even further, the performance of the D2D discovery process. Finally, the possibility of using multi-hop D2D communications for extending the coverage area of active base stations was evaluated. Improvements in energy and spectral efficiency, when compared with the case of direct UE-eNB communi- cations, were demonstrated. Moreover, UE power control techniques were applied to reduce the effects of interference from neighboring D2D links.

Rapid Prototyping of Wireless Communications Systems

Jones, Bryan Allen; Jones, Bryan Allen
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Tese de Doutorado
ENG
Relevância na Pesquisa
46.42%
Masters Thesis; This thesis introduces rapid prototyping methodology which overcomes important barriers in the design and implementation of digital signal processing (DSP) algorithms and systems on embedded hardware platforms, such as cellular phones. This thesis describes rapid prototyping in terms of a simulation/prototype bridge and in terms of appropriate language design. The simulation/prototype bridge combines the strengths of simulation and of prototyping, allowing the designer to develop and evaluate next-generation communications systems partly in simulation on a host computer, and partly as a prototype on embedded hardware. Appropriate language design allows engineers to express a communications system as a block diagram, in which each block represents an algorithm specified by a set of equations. Software tools developed for this thesis implement both concepts, and have been successfully used in the development of a type-based detector for a code-division multiple access (CDMA) cellular wireless communications system.

The Functions and Duties of the Cryptology Section, Naval Communications

Safford, Laurence F.
Fonte: Monterey, California: Naval Postgraduate School. Publicador: Monterey, California: Naval Postgraduate School.
Tipo: Aula
EN_US
Relevância na Pesquisa
36.48%
Lt. Laurance Safford, who is often called the “father” of Navy cryptology, became the officer-in-charge of the Office of Naval Intelligence Code and Signal Section in 1924. The following year, in a prescient speech to Naval Postgraduate School students, Safford said: “All nations have learned the lessons of the World War and will probably make even greater efforts to intercept and read enemy messages in the future than were made in the past…In a war between nations of approximately equal strength, Radio Intelligence could easily become the decisive factor.” By the late1920’s, NPS communications courses included coding and decoding; by the early 1930’s, cryptography and cryptanalysis. Admiral Chester Nimitz expanded NPS student input in radio engineering and communications in 1939 and later added specialized graduate programs for Navy reservists. The first reservists in communications intelligence, shown in a class photobelow, completed their studies in the summer of 1941. These NPS alumni werewell prepared for immediate assignment to cryptology units during the rapid, post-Pearl Harbor mobilization. They played an important role in breaking the Japanesecode, JN-25, which led to key victories at the Battles of Coral Sea and Midway in 1942. Captain Earl Stone...

An effectiveness study for prioritization algorithms in a communications node model for the Copernicus Tactical Data Information Exchange System (TADIXS).

Halton, Christopher H.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
36.42%
Approved for public release; distribution is unlimited; The U.S. Navy has published its vision of the future in Command, Control, Communications, Computers, and Intelligence (C4I): Copernicus. Copernicus takes advantage of new technology and attempts to answer the demand for larger amounts of more timely information. Despite the advances in technology, new transmission methods and increased bandwidth, the U.S. Navy still does not have all the communications throughput that it desires. The author examines message prioritization algorithms as a way of making more efficient use of scarce communications resources. Through a simple communications node model and two algorithms, it is statistically proven that prioritization algorithms can improve the efficiency of a communication system

Emergency mobile wirless networks: flyaway communications (FLAC) with WiMAX 802.16 technology

Donahoo, Michael; Steckler, Brian
Fonte: Carlsbad, California, Cygnus Communications, Inc. Publicador: Carlsbad, California, Cygnus Communications, Inc.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.52%
Wireless networks using 802.16 WiMAX technology in a "fly-away" communications (FLAC) package. Terrestrial communication networks continue to evolve very fast, with the extension offered by new IEEE 802.16 promising critical advantages benefiting civilian, government, Homeland Security, and crisis management in addition to the commercial market. A real world situation, such as the recent Tsunami in South East Asia is a good example of a complete collapse of the existing communications infrastructure from a natural disaster. Millions of people were left with virtually no way to communication with family, emergency responders, or potential relief supporters. Remarkable results were achieved by a group led by the Naval Postgraduate School (NPS) in establishing an ad-hoc communications network using a satellite ground station, an IEEE 802.16 router servicing an 802.11 cell phone network in Thailand shortly after all communications infrastructure was lost to the recent Tsunami. Although it was pieced together with available equipment prpovided by various companies (who will be credited in the presentation), an effective communications grid was quickly established, providing crtical connectivity to the world from the crisis area. This event gave rise to the concept that a standard "Fly-away" mobile communications network was a critical asset for worl associations such as the UN...

Algorithms for MIMO-OFDM wireless communications

García-Armada, Ana
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Relatório Formato: application/pdf
Publicado em 15/04/2008 ENG; ENG
Relevância na Pesquisa
46.42%
Communications Group of University Carlos III of Madrid has designed and implemented algorithms for the improvement of the performance of MIMO-OFDM systems. This technology is capable of providing high data rate wireless communications. The developed algorithms allow, on one side, the correction of the imperfections introduced by radio-frequency equipment and, on the other side, adaptation of the transmission to the channel characteristics.

Testbed-Assisted Learning for Digital Communications Courses

García-Naya, José A.; Castro-Castro, Paula-María; González-López, Miguel; Dapena, Adriana
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.48%
This is the peer reviewed version of the following article: Computer Applications in Engineering Education, vol. 21, no. 3, pp. 539–549, September 2013, which has been published in final form at http://dx.doi.org/10.1002/cae.20499. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.; [Abstract] We introduce testbed-assisted learning as an effective means for teaching digital communications. Laboratory teaching activities of digital communications courses benefit very much from utilizing a hardware testbed, since it greatly facilitates the understanding of very important effects introduced by real-world transceivers. We overcome the main drawback of communications hardware, that is, the cumbersome low-level programming interfaces provided by hardware manufacturers, by introducing a distributed multilayer software architecture. This architecture provides different abstraction levels to access hardware testbeds, releasing students from the low-level interaction with the hardware. Also, the distributed nature of this architecture results in a high flexibility of operation. This way, students can focus on learning communications topics without devoting any time to low-level programming...

An evaluation and comparison of the Army's acquisition plans for two tactical command control and communications systems: mobile subscriber equipment and single channel ground and airborne radio system

Williams, Denise F.; Ebener, Ralph I., Jr.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: viii, 58 p.
EN_US
Relevância na Pesquisa
46.37%
Approved for public release, distribution is unlimited; This thesis evaluates the Acquisition Plans of two US Army Command, Control and Communications (C3) systems: Mobile Subscriber Equipment (MSE) and the Single Channel Ground and Airborne Radio System (SINCGARS), both of which are components of the Army Tactical Command and Control System (ATCCS). The study examines the defense acquisition process through the comparison of the Acquisition Plans and lessons learned for these two programs, and determines if there is an optimal strategy for the Army to use when acquiring tactical C3 systems. An analysis of the strengths and weaknesses of the two Acquisition Plans, and an evaluation of the similarities and differences of two programs, concludes that the MSE Acquisition Plan proved more successful than its SINCGARS counterparts because of its Non-Developmental Item approach. This study recommends maximum use of the NDI strategy for acquiring C3 systems whenever possible.; Captain, United States Army; Captain, United States Army

Personal communications services : improving theater deployable communications for the 21st century

Cournoyer, Ronald C.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 71 p.;28 cm.
EN_US
Relevância na Pesquisa
36.56%
Personal Communications Services (PCS) may be the key ingredient for vastly improved military communications capabilities at the turn of the century. The Federal Communications Commission (FCC) defines PCS as a family of mobile or portable radio communications services which could provide services to individuals and businesses and be integrated with a variety of competing networks ... the primary focus of PCS will be to meet communications requirements of people on the move. Today's generation of Theater Deployable Communications, which provides joint tactical communications to deployed forces, is the Tri-Service Tactical Communications (TRI-TAC) system. A description of TRITAC's family of equipment, network topology, typical employment, and critical limitations is presented in this thesis. Five commercial Mobile Satellite Services (MSS) are described as viable candidates for augmenting existing communications systems. Cellular design principles such as frequency reuse, cell splitting, channel access methods, and propagation factors are also addressed. Finally, a framework for comparison of the candidate MSS systems is proposed as a baseline for further studies into the most beneficial implementation of PCS into theater deployable communications systems for the future.; NA; NA; U.S. Air Force (U.S.A.F.) author.

Blind Estimation of Perceptual Quality for Modern Speech Communications

Falk, Tiago
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1412501 bytes; application/pdf
EN; EN
Relevância na Pesquisa
36.48%
Modern speech communication technologies expose users to perceptual quality degradations that were not experienced earlier with conventional telephone systems. Since perceived speech quality is a major contributor to the end user's perception of quality of service, speech quality estimation has become an important research field. In this dissertation, perceptual quality estimators are proposed for several emerging speech communication applications, in particular for i) wireless communications with noise suppression capabilities, ii) wireless-VoIP communications, iii) far-field hands-free speech communications, and iv) text-to-speech systems. First, a general-purpose speech quality estimator is proposed based on statistical models of normative speech behaviour and on innovative techniques to detect multiple signal distortions. The estimators do not depend on a clean reference signal hence are termed ``blind." Quality meters are then distributed along the network chain to allow for both quality degradations and quality enhancements to be handled. In order to improve estimation performance for wireless communications, statistical models of noise-suppressed speech are also incorporated. Next, a hybrid signal-and-link-parametric quality estimation paradigm is proposed for emerging wireless-VoIP communications. The algorithm uses VoIP connection parameters to estimate a base quality representative of the packet switching network. Signal-based distortions are then detected and quantified in order to adjust the base quality accordingly. The proposed hybrid methodology is shown to overcome the limitations of existing pure signal-based and pure link parametric algorithms. Temporal dynamics information is then investigated for quality diagnosis for hands-free speech communications. A spectro-temporal signal representation...

Collaborative Climate Change Communications: An Assessment and Recommendations for the Future

Tollefson, Christopher
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 28/04/2011 EN_US
Relevância na Pesquisa
36.56%
The threat posed by anthropogenic climate change to the world’s wildlife and natural systems has prompted the conservation community in the United States and across the globe to make communicating about climate change one of their highest, if not the highest, priorities. At one level, these communication efforts seem to be working. Multiple surveys confirm that most Americans believe that climate change is occurring, and that it is caused at least in part by human activities. However, in recurring national surveys, climate change has consistently ranked near the bottom of environmental issues Americans are concerned about. This Master’s Project assesses the current state of climate change communications at federal agencies, conservation organizations and other entities that are working to address the impacts of climate change on wildlife and natural systems, and identifies best practices in climate communications. As part of the project, a survey was conducted of professional communicators from multiple federal agencies, conservation organizations, professional societies and groups representing states and tribes. Data analysis of the survey, as well as a review of current literature on effective climate change communications and public attitudes...

Media literacy and the Communications Act: what has been achieved and what should be done? A 2013 update

Livingstone, Sonia; Wang, Yinhan
Fonte: Department of Media and Communications, London School of Economics and Political Science Publicador: Department of Media and Communications, London School of Economics and Political Science
Tipo: Monograph; NonPeerReviewed Formato: application/pdf
Publicado em /01/2013 EN; EN
Relevância na Pesquisa
46.31%
Progress in digital skills has stalled. Despite growing broadband adoption and a range of media literacy initiatives, the evidence shows little improvement in adult or children’s levels of knowledge over the past few years. This is especially the case for the crucial dimensions of critical and participatory literacy. Yet citizens and consumers must rely on their digital skills as never before. Rapid transformations in the digital media landscape have put increasing pressure on individuals to navigate highly complex technologies, risking digital exclusion, consumer detriment, low participation and growing inequality. Government support has been cut just when it is most needed. Industry support is also vital, but needs a national effort to maximise visibility and coordination. Carefully targeting the promotion and resourcing of media literacy for those most in need could make a real difference. The effective promotion of digital skills and media literacy across the population should be a priority for the upcoming Communications White Paper.

Reforming consumer representation in UK communications

Tambini, Damian
Fonte: Department of Media and Communications, London School of Economics and Political Science Publicador: Department of Media and Communications, London School of Economics and Political Science
Tipo: Monograph; NonPeerReviewed Formato: application/pdf
Publicado em /09/2011 EN; EN
Relevância na Pesquisa
46.45%
Communications consumers in the UK do not switch provider enough, and when they do they sometimes do so irrationally. As the government conducts a welcome review of the landscape of consumer representation in the UK, they should be aware that there is an ongoing, permanent need for consumer representation that is specific to the communications sector. The government’s proposals, by shifting consumer advocacy to the Citizen’s Advice Bureau, are likely to result in an increase in costs to the public purse. Within the current model Ofcom and its consumer panel receive almost half their funding from the private sector. If the body is moved to Citizens Advice, the proportion met by public funding will be higher. The fast changing, technical complexity of the communications sector makes a consumer representative particularly important. Consumer advocacy in communications will be most efficient if it is within Ofcom, but has much more effective operational independence from it.