Com a evolução tecnológica há nos dias de hoje um aumento de dispositivos eletrônicos presentes ao nosso redor. Com o passar dos anos diversas funcionalidades vêm sendo agregadas a estes inclusive com maior poder de processamento. Em particular, para sistemas embarcados houve um crescimento da quantidade de sensores para diversos propósitos. Seguindo esta tendência, na área de saúde também houve um aumento significativo de aparelhos e dispositivos de monitoramento, tais como glicosimetros, oxímetros, monitoramento de pressão e batimento cardíaco por exemplo, que através de sensores realizam transdução dos dados pertinentes ao parâmetro envolvido. Este trabalho apresenta a pesquisa e o desenvolvimento de um sistema embarcado com a propriedade de multiplexação de sensores, ou seja, foi desenvolvido um dispositivo microcontrolado o qual visa multiplicar a capacidade de monitoramento de analitos, conseguindo analisar múltiplos sensores para um mesmo experimento. Ao decorrer deste desenvolvimento foram utilizados quatro sensores dispostos simetricamente em um béquer, os dados são coletados e tratados de forma sequencial e individual. Inicialmente utilizamos um sistema embarcado com um microcontrolador (PIC 18F2550) que é responsável por digitalizar a informação e pela conexão via terminal USB. Posteriormente um microprocessador (Raspberry Pi Zero, placa embarcada) fez-se necessário devido ao melhor processamento de dados. Os sensores aqui estudados tratam-se de sensores químicos, que são introduzidos a uma célula eletroquímica, onde se encontram um eletrodo de referência (Prata em uma solução de Cloreto de Prata) e os outros quatro filmes finos que irão compor o sistema multiplexado. Para este estudo em específico o material escolhido para fabricação dos filmes finos foi um polímero condutivo, mais especificamente polianilina (PANI). Esta foi depositada sobre um substrato de oxido de estanho dopado com flúor (FTO) através da eletrodeposição. Para sensores não específicos (não imobilizados para um analito alvo) os dois sistemas embarcados apresentaram respostas satisfatórias. Prosseguindo com o estudo e usando filmes finos para analitos biológicos (ureia e glicose) o microcontrolador não conseguiu separar os sinais de cada filme fino. Apenas o sistema com a Raspberry Pi obteve sucesso, devido a maior resolução no conversor analógico para digital e sua maior capacidade de processamento para determinar com uma maior precisão os valores obtidos. O sistema pode ser facilmente expandido para um maior número de sensores. / With the evolution of technology there is nowadays an increase in the number of electronic devices present around us. Over the years various functionalities have been added to these devices including the increased processing power. In particular, for embedded systems there has been an increase in the number of sensors for various purposes. Following this trend, in the area of health, there has also been a significant increase in systems and monitoring devices, such as glycosimeters, oximeters, pressure monitoring and heart rate, for example, which, through sensors, transduce data pertinent to the parameter involved. This work presents the research and development of an embedded system with the property of multiplexing sensors, that is, a microcontrolled device was developed which aims to multiply the capacity of analytes monitoring, being able to analyze multiple sensors for the same experiment. During this development four sensors were used symmetrically arranged in a beaker, the data were collected and treated sequentially and individually. Initially we used an embedded system with a microcontroller (PIC 18F2550) that is responsible for scanning the information and for the connection via USB terminal. Subsequently a microprocessor (Raspberry Pi Zero, embedded board) was made necessary due to the better processing of data. The sensors studied here are chemical sensors, which are introduced to an electrochemical cell, where a reference electrode is found (Silver in a Silver Chloride solution) and the other four thin films that will make up the multiplexed system. For this specific study the material chosen for the manufacture of thin films was a conductive polymer, more specifically polyaniline (PANI). This was deposited on a substrate of fluorine-doped tin oxide (FTO) by electrodeposition. For non-specific sensors (not immobilized for a target analyte) the two embedded systems presented satisfactory responses. Proceeding with the study and using thin films for biological analytes (urea and glucose) the microcontroller failed to separate the signals from each thin film. Only the system with Raspberry Pi has been successful, due to the higher resolution in the analog to digital converter and its greater processing capacity to determine with greater precision the obtained values. The system can be easily expanded to a larger number of sensors.

No description available.

The X Window System is an industry-standard software system which facilitates programmers to develop portable graphical user interfaces. This thesis describes an image processing tool developed under the X Window System. A multiwindow image display software with image editing and improvement functions is developed. The software has four modules: environment generation, image creation, image editing and image improvement. The environment generation module creates working windows, scrollbars, dialogbox and pulldown menu buttons, and tracks mouse cursor positions. The working windows are three adjacent windows allowing display of three different images simultaneously. The dialogbox provides an interface between the user and the program, such as input new image and parameters. The pulldown menus offer various selections of image processing functions. A pair of scrollbars are also added to allow users to move the magnified image up, down, left and right so that the full picture can be viewed. The image creation module can build colormap, load image data file, convert pixel values to screen color values, create image, and display image on the screen of a workstation. The program can read either sun.rasterfile format or a plain data file. If a plain data file is detected, the software can transform it to sun.rasterfile by adding an appropriate header and a colormap. There are two kinds file saving features: screen capture and store. The screen capture allows the user to save that part of image displayed on the screen. The store function saves the entire image which may be either the screen size or bigger size image (e.g. merged or zoomed image). The image editing module is equipped with the functions for zooming (in or out) , merging, rotating and restoring images. The merge function constructs a new image based on the user selected or input image from the dialogbox. The rotation center of an image can be any point selected by user's clicking mouse button, and the rotation angle is supplied by user in the dialogbox. The image improvement module consists of some image point transformation and image enhancement functions. This software package is easier to use than existing tools for image processing. It has been used in the image processing projects and related educational purposes. The software provides a framework and can be easily extended to other potential applications.

The development and testing for a UAV testbed to be used in academic research and undergraduate education is proposed in this thesis. Analysis on commercial off-the-shelf UAV systems and autopilots lead to the development of a custom, open-architecture and modular UAV testbed. The main focus is to support research in UAV control field and education of the undergraduate students. The integration and use of commercial-off-the-shelf avionics and air vehicle are described in detail. System performance is examined both in flight and on the ground. Results of the system tests show that the developed system is a functional UAV testbed to be used in research of different flight control algorithms.

In the traditional mobile communication networks, the bandwidth of wireless links is too small and the bandwidth difference between wireless links and wireline links is too large. This leads to limiting the application of mobile communication networks to transmit multimedia data and other high-bit rate services, and the problem of lacking bandwidth often occurs to wireless links. But the new generation mobile communication networks, called the third generation mobile communication systems (3G systems), will change this condition. Because the 3G systems will quickly enhance the transmission rate of the wireless links (up to 2Mbps) and provide better quality of transmission, the transmission of multimedia data and other high-bit rate services in the mobile communication networks can be achieved. The 3G systems can support many new services that are never supported before, and these new services always need support the point-to-multipoint transmission. In this thesis, we will discuss the problems of supporting these new services, and then we propose new multimedia multicasting architecture to overcome these problems.

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 80-84).

Thesis (Ph. D.)--University of Missouri--Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 63-74). Also available on the Internet.

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 100-132).

Zugl.: Hagen, Fernuniv., Diss., 2009

Thesis (M.S.) -- Mississippi State University. Department of Industrial Engineering. / Title from title screen. Includes bibliographical references.