Estudo do efeito de dipolos em arranjos de antenas adaptativas de sistemas de comunicação DS-CDMA

This master dissertation introduces a study about some aspects that determine the aplication of adaptative arrays in DS-CDMA cellular systems. Some basics concepts and your evolution in the time about celular systems was detailed here, meanly the CDMA tecnique, specialy about spread-codes and funtionaly principies. Since this, the mobile radio enviroment, with your own caracteristcs, and the basics concepts about adaptive arrays, as powerfull spacial filter was aborded. Some adaptative algorithms was introduced too, these are integrants of the signals processing, and are answerable for weights update that influency directly in the radiation pattern of array. This study is based in a numerical analysis of adaptative array system behaviors related to the used antenna and array geometry types. All the simulations was done by Mathematica 4.0 software. The results for weights convergency, square mean error, gain, array pattern and supression capacity based the analisis made here, using RLS (supervisioned) and LSDRMTA (blind) algorithms

Uma nova proposta de antenas Quasi-Yagi banda larga para comunicação sem fio

ln this work, planar quasi- Y agi antennas are investigated based on the concept of the classic Y agi_Uda antennas. These antennas represent improvements on the topologies of the antennas existing printed because they present characteristics of broad bandwidth, excellent radiation diagrams and simple construction. New configurations are adapted for the driver of the antennas, introducing patches elements into the driver. These new configurations are named Patches Elements Anteonas (PEA). This adaptation is obtained from simulations that are executed usiog the software C8T Microwave 8tudio 5. After doing the optimizations, procedures for construction and measurement ofthe prototypes are executed in order to improve the performance of the antennas in such way that they could be used in wireless communication applications, such as Bluetooth, WLAN' s and Wi-Fi. Next, the quasi- Y agi antennas are studied in order to implement them in arrangements. The arrangements construction is based 00 the best driver configuration of the antenna developed in this work. First, a linear arrangement composed by two elements of quasi¬Yagi antennas is constructed in such way that the radiation characteristics and the mutual coupling effects could be analyzed. After that, a 90° angle arrangement composed by two elements is studied to observe the effect of circular polarization. Experiments are executed in order to evaluate the arrangements performance. The experimental results show that the analysis made in this work is efficient and accurate. The numerical values obtained for the analyzed parameters of each structure developed are compared with the experimental values. 80, it is possible to observe a good concordance between them. Finally, some future works proposals are presented

Desenvolvimento de um software de comunicação sem fio aplicado à instrumentação de unidade de elevação de petróleo tipo Plunger Lift

This dissertation aims to develop a software applied to a communication system for a wireless sensor network (WSN) for tracking analog and digital variables and control valve of the gas flow in artificial oil s elevation units, Plunger Lift type. The reason for this implementation is due to the fact that, in the studied plant configuration, the sensors communicate with the PLC (Programmable and Logic Controller) by the cables and pipelines, making any changes in that system, such as changing the layout of it, as well as inconveniences that arise from the nature of the site, such as the vicinity s animals presence that tend to destroy the cables for interconnection of sensors to the PLC. For software development, was used communication polling method via SMAC protocol (Simple Medium Access ControlIEEE 802.15.4 standard) in the CodeWarrior environment to which generated a firmware, loaded into the WSN s transceivers, present in the kit MC13193-EVK, (all items described above are owners of Freescale Semiconductors Inc.). The network monitoring and parameterization used in its application, was developed in LabVIEW software from National Instruments. The results were obtained through the observation of the network s behavior of sensors proposal, focusing on aspects such as: indoor and outdoor quantity of packages received and lost, general aspects of reliability in data transmission, coexistence with other types of wireless networks and power consumption under different operating conditions. The results were considered satisfactory, which showed the software efficiency in this communication system

Antenas e superfícies seletivas de freqüência reconfiguráveis para sistemas de comunicação sem fio

This work aims to present how the reconfigurable microstrip antennas and frequency selective surfaces can be used to operate at communication systems that require changing their operation frequency according to system requirements or environmental conditions. The main purpose is to present a reconfigurable circular microstrip antenna using a parasitic ring and a reconfigurable dipole frequency selective surface. Thereupon there are shown fundamental topics like microstrip antennas, PIN diodes and the fundamental theory of reconfigurable antennas and frequency selective surfaces. There are shown the simulations and measurements of the fabricated prototypes and it is done an analysis of some parameters like the bandwidth and radiation pattern, for the antennas, and the transmission characteristics, for the frequency selective surface. Copper strips were used in place of the diodes for proof of the reconfigurability concept

Utilizando a televisão digital como um meio de comunicação para ambientes interativos reais

This Dissertation aims to provide a communication mechanism between Digital TV viewers and interaction devices, such as robots, for example, placed on the environment from which a TV program is being live broadcasted. Such communication mechanism has the objective to allow viewers controll the Interaction Devices through their TV devices, using the broadcast channel present in Interactive Digital TV systems, and receive data from the devices by the broadcast channel. This system was projected as a middlewaer system where the Interaction Devices in the TV program set are interconnected, creating a Interactive Device Network. With this approach, the system is capable of manage the devices on the network, controlling the flow of coming and leaving elements, in a transparent way for the viewers. The system yet allows the Interaction Devices communicate each other, with a integrated communication channel with no worries about the physical communication layer

Modelo arquitetural de comunicação para monitoramento de pacientes baseado em middleware, computação móvel e ubíqua

Hospital Automation is an area that is constantly growing. The emergency of new technologies and hardware is transforming the processes more efficient. Nevertheless, some of the hospital processes are still being performed manually, such as monitoring of patients that is considered critical because it involves human lives. One of the factors that should be taken into account during a monitoring is the agility to detect any abnormality in vital signs of patients, as well as warning of this anomaly to the medical team involved. So, this master's thesis aims to develop an architecture to automate this process of monitoring and reporting of possible alert to a professional, so that emergency care can be done effectively. The computing mobile was used to improve the communication by distributing messages between a central located into the hospital and the mobile carried by the duty

Estudo do efeito de dipolos em arranjos de antenas adaptativas de sistemas de comunicação DS-CDMA

This master dissertation introduces a study about some aspects that determine the aplication of adaptative arrays in DS-CDMA cellular systems. Some basics concepts and your evolution in the time about celular systems was detailed here, meanly the CDMA tecnique, specialy about spread-codes and funtionaly principies. Since this, the mobile radio enviroment, with your own caracteristcs, and the basics concepts about adaptive arrays, as powerfull spacial filter was aborded. Some adaptative algorithms was introduced too, these are integrants of the signals processing, and are answerable for weights update that influency directly in the radiation pattern of array. This study is based in a numerical analysis of adaptative array system behaviors related to the used antenna and array geometry types. All the simulations was done by Mathematica 4.0 software. The results for weights convergency, square mean error, gain, array pattern and supression capacity based the analisis made here, using RLS (supervisioned) and LSDRMTA (blind) algorithms.

Desenvolvimento de um protocolo de comunicação para automação de subestações móveis via satélite

One of the most important decisions to turn a substation automatic and no attended it relates to the communication media between this substation and Operation Center. Generally energy companies uses radio or optic fiber, depending of distances and infrastructure of each situation. This rule applies to common substations. Mobile substations are a particular case, therefore they are conceived for use at provisional situations, emergencies, preventive or corrective maintenance. Thus the telecommunication solution used at common substations are not applied so easily to mobile substations, due absence of infrastructure (media) or difficulty to insert the mobile substation data in existing automation network not long. The ideal media must supply covering in a great geographic area to satisfy presented requirements. The implantation costs of this big infrastructure are expensive, however a existing operator may be used. Two services that fulfill that requirements are satellite and cellular telephony. This work presents a solution for automation of mobile substations through satellite. It was successfully implanted at a brazilian electric energy concessionaire named COSERN. The operation became transparent to operators. Other gotten benefits had been operational security, quality in the supply of electric energy and costs reduction. The project presented is a new solution, designed to substations and general applications where few data should be transmitted, but there is difficulties in relation to the media. Despite the satellite having been used, the same resulted can be gotten using celullar telephony, through Short Messages or packet networks as GPRS or EDGE.

Desenvolvimento de um middleware para comunicação via web services e sua aplicação em sistemas de aquisição de dados industriais

The control of industrial processes has become increasingly complex due to variety of factory devices, quality requirement and market competition. Such complexity requires a large amount of data to be treated by the three levels of process control: field devices, control systems and management softwares. To use data effectively in each one of these levels is extremely important to industry. Many of today s industrial computer systems consist of distributed software systems written in a wide variety of programming languages and developed for specific platforms, so, even more companies apply a significant investment to maintain or even re-write their systems for different platforms. Furthermore, it is rare that a software system works in complete isolation. In industrial automation is common that, software had to interact with other systems on different machines and even written in different languages. Thus, interoperability is not just a long-term challenge, but also a current context requirement of industrial software production. This work aims to propose a middleware solution for communication over web service and presents an user case applying the solution developed to an integrated system for industrial data capture , allowing such data to be available simplified and platformindependent across the network

Mercadores de sentidos: a comunicação de vendedores ambulantes com estrangeiros por meio da intercompreensão multilíngue

This paper aims, starting with the studies of languages in contact and communicative competence, to locate and describe the interlanguage, a linguistic phenomenon observed in the interaction between beach sellers and foreign tourists. We seek to discover whether those interacting use some kind of pidgin, or some code as a lingua franca. We also seek to identify the manner in which the features of communicative competence are presented by analyzing the various competences that composes it - linguistic, sociolinguistic, pragmatic and psycholinguistic. The analysis of speech acts, the maxims and conversational implicatures given in the corpus were important to verify whether those interacting were successful in their attempt at multilingual intercomprehension.

Registros de ordens e ocorrências: uma prática de letramento no trabalho da enfermagem hospitalar

Nursing documentation is a literacy practice which is regulated by law. Among the written practices of the literacy field, nursing registration is understood as the attendance resume of the main problems and occurrences on duty. In other words it is a document and a communication instrument used by hospital orderly on duty. It s main goal is to keep a record of the information which is necessary to the continuity of the activities as well as to the assistance to the patients. Taking into consideration the complexity of this kind of literacy practice, this study which took place in a hospital context, aims at studying the nursing registration process in order to explain its implementation in the nursing field. The discussion is situated in the area of applied linguistics, and it makes a linkage between linguistics approaches and language questions which are related to the area of discourse at work. The theoretical foundations come from contemporary literacy studies such as Hamilton (2000) who proposes the following categories: participants, domain, artifacts and activities. The analysis was guided by the principles of the ethnographic methodology which proposes that the researcher spends much time in the field and uses a set of techniques in order to collect data related to the subjects speech as well as their deeds concerning the research main object. The data were collected through field observations, analysis of 100 nursing records, 04 reflective sessions and interviews as well involving 36 nurses. On one hand, the analysis reveals the importance of the nursing records in terms of documentation and communication. On the other hand, it shows informational, compositional as well as normative difficulties in terms of linguistics and legal aspects. For, we conclude that these questions need to be addressed through the process of intervention especially in events of teacher in service activities so that the professional nurses may improve their practice in relation to the elaboration of the nursing documentation on duty

Comunicação gráfica em interfaces de hipermídia de educação a distância via web

This study aims to analyze the communication graphics of layouts of hypermedia interfaces oriented to Distance Education via the Internet. This proposal is justified by widening the offer of courses that modality and the consequent application of items of hypermedia for teaching-learning. The method of analysis involved the search nethnographic, addressed to the cycle student intermediary of the Training Program Continuing Medias in Education, and the evaluation heuristic of the interfaces of Virtual Learning Environment "E-Proinfo" and of the modules of the Cycle. This evaluation we observed the implementation of the attributes of usability and the degree of interactivity of each interface. The results revealed an inefficient implementation of the attributes of usability, which meant a consequent reduction of the levels of interactivity. As proposing the present Design Virtual Learning, a model of hypermedia layout, designed to generate usability for Virtual learning environments and extend the acquisition of literancy for students and tutors. This proposal design not hypermedia aims the demarcation of models pre-conceived, but the proposal of layout in which each element of hypermedia is applied with a view to generate a seaworthiness intuitive, more agile and efficient, in these ambients

O jogo das identidades como fator de mobilização político-eleitoral nas campanhas de Dilma Rousseff e Rosalba Ciarlini em 2010

Starting from the premise that we live in the society of spectacle, as proclaimed by Guy Debbord, and, in this context, the media feeds itself off of this spectacularization and constructs a culture of images and production of goods, providing templates from which the subject can identify himself/herself as being male or female, successful or unsuccessful, powerful or powerless. In other words, the culture conveyed by the media produces material for the creation of identities through which individuals insert and recognize themselves in contemporary society. Observing the election campaigns, we can see clearly that this profusion of identities is fairly explored in the advertising propaganda used by the candidates, particularly in the propaganda broadcasted on the Free Electoral Time on TV. Instigated by the explicit relation between the media and politics within the society of the spectacle, this study aims to investigate the main identities that emerge in the discursive practices of the media in the election campaigns of 2010 for president of the Republic and governor of the State of Rio Grande do Norte that had as protagonists the candidates at that moment Dilma Rousseff (PT) for president and Rosalba Ciarline (DEM) for governor. To do so, we based ourselves on the theory of Bakhtin Circle, which considers the statement as a unit of verbal communication and conceives language as a dialogical phenomena and a discursive practice and also in the conceptions of dialogical relationships, social voices and chronotope formulated by the previous mentioned theory. Still in the theoretical field, we have established an interconnection with the theories coming from the Cultural Studies (Hall, Woodward) about the identity, which conceives it as multiple, fragmented, non-fixed, so that, the subject assumes different identities, not always coherent, at different times, depending on the context in which they are approached. The research is situated in the frames of Applied Linguistics, which considers language as the center of its studies and settles on the border of an open number of areas of knowledge expanding its possibilities of investigation by means of the interdisciplinary. Our corpus consists in 20 electoral propaganda videos aired on TV during the Free Election Time in 2010 campaign; among these, 14 videos are Dilma Rousseff s propaganda and 06 videos are Rosalba Ciarline s propaganda. We seek for the purpose of the analysis to identify the identities which emerge from the discourses about the candidates in propaganda videos broadcasted in the referred campaign, as well as realize the dialogical relations established in these discourses and even if the identity construction of these subjects is located in the same axiological axis. The corpus analysis revealed that the multiple cultural identities of the candidates campaigning emerge in the discourses circulating in the electoral propaganda aired on TV such as: the identities of pioneer woman, competent, sensitive, mother, grandmother, religious. And, yet, those are changeable as the electoral demands, in other words, the need to obtain support and votes, outline a fluid identity construction about the candidate to the position in question

Casal nacional: significações do corpo e do figurino no telejornalismo

The main objective of this study is to investigate the meanings of body and costume as essential components of television journalists aesthetic discourse, as exemplified by the presenters of Jornal Nacional, from Rede Globo. The study is inspired on the paths proposed by semiotics, and combines this approach with other techniques of scientific investigation to identify the meanings of this non-verbal communication form. For that, this work uses the concept of communication proposed by the Palo Alto School s authors, more specifically the concept of Watzlawick et al. (2005), which understands communication like relation and inherent of human beings. The precepts of complex thought and the hologramatic principle of Morin (1990), which value the union and the need to connect the knowledge of elements or parts to that of the systems these parts constitute, is also present in the thinking that guides the work. Throughout the chapters, we elucidate our understanding of body and television as media, and fashion and television journalism as languages. This work approaches a televisual history of Jornal Nacional in order to better understand the aesthetic proposed by television news over time, its presenters and costumes. The elements that are part of the televisual language s expression and content are addressed so that we can better understand the importance of body and presenters costume in this context. Finally, we conduct an analysis of the meanings of television journalism presenters body and costume through their stereotypes, their integration into the fashion cycle and also into the televisual analysis of the most important costume elements of Jornal Nacional s presenter couple: colors, models and accessories. We thus seek to strengthen the understanding of the wardrobe inseparable from the body as communication and detail some of their production understanding processes. The women historical role in brazilian television journalism, as well as masculinization of TV journalism environment are important elements to contextualize televisual language thinking in contemporary society. The investigation covers the origins, concepts, proposals, stereotypes, prejudices, reproductions, naturalizations and reinterpretation of the body and the costume of the presenters through time and the relationship between body, fashion and communication

Das estantes para a tela: práticas de leitores de livros impressos e digitais do curso de Comunicação Social da Universidade Federal do Rio Grande do Norte

La cultura del libro impreso impregna la vida cotidiana de los lectores durante más de cinco siglos, y de esto, hábitos y significados a cerca del libro como medio de comunicación tienen sus raíces en la comunidad lectora, en una especie de contrato de lectura (VERÓN, 2004). Por lo tanto, creemos que es posible conjeturar que la aparición del libro digital puede cambiar las viejas prácticas en relación con el libro impreso y por eso mismo deben ser investigadas con el fin de entender este tiempo de productos reconfigurados. Consciente de ello, el tema central de nuestra investigación se basa en la comprensión de cómo los lectores de libros digitales realizan sus prácticas. Nuestro objetivo general es investigar las prácticas socioculturales de los lectores de libros digitales, con el fin de mostrar las continuidades y discontinuidades en el uso del libro en su formato impreso y digital. Con este fin, se busca 1) proponer una caracterización de la cultura del libro impreso, que es el apoyo a una asignación posible de las marcas de una cultura del libro digital, y 2) explorar los lugares de producción y oferta de los libros digitales, especialmente en Brasil, fin de delimitar en su primera configuración. Apoyamos, como propuesta metodológica, la sistematización de dimensiones culturales del libro impreso llamadas: ritualidad, simbología, materialidad y forma, lo que ayudará el enfoque del empírico. Nuestra propuesta se basa, en varios puntos, en los investigadores de la historia del libro, insertada en el campo de la Historia Cultural (BURKE, 2008; CHARTIER, 1992, 1994, 2006; DARNTON, 1990, 2006, 2010). Adoptamos como técnica de investigación el análisis de voces, registradas a través de entrevistas en profundidad, de lectores de libros en formato digital. Antes de eso, creemos apropiado emprender un estudio exploratorio basado en la aplicación de un cuestionario online. Nuestra delimitación incluye lectores de libros digitales del curso de Comunicación Social de la Universidad Federal de Rio Grande do Norte. Entre las conclusiones de esta disertación, es posible señalar que el grupo de lectores investigados está sólidamente ligado a las experiencias con los libros impresos y esto afecta en gran medida las prácticas de los libros digitales