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  • 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.
201

DatAssist : the development of a portable multi-purpose medical data acquisition system / DatAssist : η ανάπτυξη ενός φορητού, πολύ-χρηστικού [sic] συστήματος ανάκτησης ιατρικών δεδομένων

Νικολαΐδης, Νικόλαος 20 October 2010 (has links)
Κατά τη διάρκεια τόσο των ιατρικών διεργασιών μέσα στο νοσοκομείο – όπως των απλών τεστ που διενεργούνται στους ασθενείς, αλλά και των πιο περίπλοκων διεργασιών των μεταμοσχεύσεων και των χειρουργείων, όσο και των in vitro τεστ, διάφορες παράμετροι πρέπει συνεχώς να μετρούνται και να απεικονίζονται, για παράδειγμα η πίεση, η ροή και η θερμοκρασία του αίματος και των ειδικών διαλυμάτων διατήρησης των οργάνων που χρησιμοποιούνται κατά τη διάρκεια των μεταμοσχεύσεων. Η πίεση και η ροή του αίματος καθώς και η θερμοκρασία του σώματος, ως πολύ σημαντικές φυσιολογικές παράμετροι που είναι, πρέπει να μετρούνται με τη μέγιστη δυνατή ακρίβεια έτσι ώστε να δίνεται συνεχώς μια σαφής εικόνα της λειτουργίας του ανθρωπίνου σώματος. Μέχρι τώρα, οι μετρήσεις αυτών των παραμέτρων διενεργούνταν από ξεχωριστές μονάδες μέτρησης και επιπλέον από ξεχωριστά συστήματα ανάκτησης δεδομένων (Data Acquisition Systems), με αποτέλεσμα το αυξημένο κόστος λειτουργίας και την αύξηση της περιπλοκότητας των μετρήσεων για τον χρήστη. Το DatAssist δημιουργήθηκε επάνω στην ιδέα ανάπτυξης ενός φορητού συστήματος μετρήσεων με ενσωματωμένη επεξεργασία των δεδομένων μέτρησης, το οποίο θα έχει τη δυνατότητα απεικόνισης όλων των φυσιολογικών παραμέτρων που αναλύθηκαν παραπάνω. Επιπλέον, θα έχει τη δυνατότητα αποθήκευσης όλων των δεδομένων για περαιτέρω ανάλυση. Το DatAssist σκοπεύει να παρέχει ακριβείς μετρήσεις, ευκολία στη χρήση και καθαρή πληροφόρηση για τις μετρούμενες παραμέτρους στην οθόνη. Επιπρόσθετα ο σχεδιασμός του έγινε έτσι ώστε να έχει το λιγότερο δυνατό βάρος για να μπορεί να μετακινείται εύκολα κατά την διάρκεια ιατρικών εφαρμογών. Το DatAssist σχεδιάστηκε με βάση το πρότυπο IEC 60601-1:2005 και σκοπεύει να αποτελέσει ένα πολυκάναλο σύστημα με ευκολία εισαγωγής επιπρόσθετων στοιχείων στο εσωτερικό του, το οποίο θα χρησιμοποιηθεί από την Organ Assist B.V. Netherlands, spin-off εταιρίας του University Medical Centre Groningen, για λογαριασμό της οποίας σχεδιάστηκε στα πλαίσια της παρούσας εργασίας. Η επιδιωκόμενη χρήση της μονάδας είναι αρχικά η χρήση της για εργαστηριακά πειράματα σε ζώα, στα πλαίσια των τεστ λειτουργίας που διενεργεί η Organ Assist B.V. Netherlands στις δικές της συσκευές. Στο μέλλον, θα χρησιμοποιηθεί σε κλινικές έρευνες και κατά τη διάρκεια μεταμοσχεύσεων και χειρουργείων. Η πίεση και η ροή του αίματος, καθώς και η θερμοκρασία του σώματος και των οργάνων θα μετριέται με τη χρήση αναλώσιμων ή εύκολα αποστειρώσιμων αισθητήρων, ειδικών για ιατρικές μετρήσεις. Πιο αναλυτικά, το σύστημα παρέχει συνδέσεις με δύο αισθητήρες πίεσης, δύο αισθητήρες θερμοκρασίας (ένα Θερμοζεύγος και έναν τύπου NTC), έναν αισθητήρα ροής και επίσης έχει μια υποδοχή BNC για μέτρηση και απεικόνιση εξωτερικών σημάτων από άλλες ιατρικές συσκευές. Υπάρχει επίσης η δυνατότητα σύνδεσης περισσότερων αισθητήρων ανάλογα με τις ανάγκες του εκάστοτε χρήστη. Το σύστημα τροφοδοτείται από μια χαμηλή DC τάση μέσω ενός AC/DC Adapter, και με αυτόν τον τρόπο παρέχει τόσο ασφάλεια στον χρήστη από ηλεκτροπληξία η οποία προκαλείται από την υψηλή AC τάση, όσο και αποφυγή καταστροφής των ηλεκτρικών εξαρτημάτων της συσκευής. Ο σχεδιασμός του DatAssist βασίστηκε στις απαιτήσεις της Organ Assist B.V. με βάση την κάλυψη των αναγκών των βασικών χρηστών της συσκευής, όπως των χειρούργων και των χειριστών ιατρικών μηχανημάτων. Οι απαιτήσεις των τελευταίων συνοψίστηκαν σε εφτά γενικές προϋποθέσεις (σε μια Λίστα Προϋποθέσεων η οποία αναλύεται εκτενώς στο 2ο κεφάλαιο της παρούσας εργασίας) που αποτέλεσαν και τις προϋποθέσεις που το μηχάνημα καλούταν να καλύπτει: εγκυρότητα, ποιότητα, ασφάλεια, ευκολία χρήσης, ευκολία μετακίνησης, χαμηλό κόστος κατασκευής και χρήση εξαρτημάτων πιστοποιημένων κατά CE. Επιπλέον, τρεις ακόμη προϋποθέσεις λήφθηκαν υπόψη για τον σχεδιασμό των διαφόρων εξαρτημάτων της συσκευής: ευκολία αποστείρωσης, ευκολία εισαγωγής επιπρόσθετων εξαρτημάτων και δυνατότητα χρήσης των τελευταίων τόσο στο αίμα όσο και μέσα σε διαλύματα. Οι πιο σημαντικές λειτουργίες που καλείται να επιτελέσει το DatAssist είναι: η ανίχνευση των φυσικών παραμέτρων (πίεσης, θερμοκρασίας και ροής) από τους αισθητήρες, η ενίσχυση των αναλογικών σημάτων εισόδου των αισθητήρων, η επεξεργασία και η ψηφιοποίηση των ενισχυμένων σημάτων, η τελική επεξεργασία των ψηφιακών σημάτων από έναν υπολογιστή και τελικά η συνεχής απεικόνιση των σημάτων σε μια οθόνη monitor με την βοήθεια ενός προγράμματος Software (LabView 8.5). Για καθεμία από τις παραπάνω λειτουργίες ακολουθήθηκε μια συγκεκριμένη διαδικασία για να ορίσει τον σχεδιασμό της υλοποίησής της. Αυτή η διαδικασία είχε ως αποτέλεσμα την επιλογή των εξαρτημάτων που θα χρησιμοποιηθούν στην τελική συσκευή, έπειτα από μια αξιολόγηση των υποψήφιων εξαρτημάτων, για κάθε λειτουργία βασισμένη στην εκπλήρωση των προαναφερθέντων προϋποθέσεων, με τη χρήση της κλίμακας 1-10 (1-μη εκπλήρωση, 10-πλήρης εκπλήρωση). Επιπρόσθετα, για κάθε στάδιο του σχεδιασμού που ορίζεται από τις προαναφερ-θείσες λειτουργίες, αναπτύχθηκε ένα λειτουργικό μοντέλο (functional model) το οποίο περιείχε τον τελικό σχεδιασμό του κάθε σταδίου, καθώς και ένα τεστ που μετράει την λειτουργικότητα του κάθε σταδίου, την εγκυρότητα, το σφάλμα και μια εκτίμηση της ακρίβειας των μετρήσεων. Τελικά, η εργασία είχε ως αποτέλεσμα την κατασκευή ενός πρωτοτύπου του DatAssist βασισμένο στον σχεδιασμό που αποφασίστηκε και εγκρίθηκε από την Organ Assist B.V., το οποίο ικανοποιεί τις προϋποθέσεις που αναλύονται στην Λίστα των Προϋποθέσεων (List of Requirements). Το πρωτότυπο αυτό στη συνέχεια ελέγχεται όσον αφορά την ακρίβεια των μετρήσεων και την ικανοποίηση της Λίστας των Προϋποθέσεων . Έτσι, αυτή η εργασία είχε ως τελικό αποτέλεσμα την σχεδίαση ενός εγκύρου, εύκολα αποστειρώσιμου, φορητού, εύκολου στη χρήση, ασφαλούς για τον χρήστη πολυχρηστικού συστήματος μέτρησης ιατρικών δεδομένων με κόστος δημιουργίας και μετέπειτα πώλησης λιγότερο από 3000 €. / During both inside the hospital medical procedures-from simple patient tests to more sophisticated procedures such as transplantations and surgeries, and laboratory or animal testing, several parameters have to be measured and monitored i.e. pressure, flow and temperature of blood and of the perfusion solution during transplantations. Since blood pressure, blood flow and body temperature have shown to be important physiological parameters, they have to be measured and registered accurately in order to monitor the functioning of the human body. Up to now, these measurements had to be performed with separate measuring units and separate data acquisition systems and thus with increased cost and resulting to a complicated measuring procedure for the user. The idea of the DatAssist project is to develop a portable measuring system with integrated data acquisition that is able to monitor and display all these physiological parameters and save them for later analysis for Organ Assist -a spin-off company of the University Medical Centre Groningen. DatAssist will provide accurate measurements, it will be easy to use and give clear information about the measured parameters in the monitor. It will also be as much light-weighted as it can in order to be easy to move during medical applications. DatAssist intends to be a modular multi-channel system and is going to be designed according to IEC 60601-1:2005 regulations. The intended use of the unit is primary for animal and laboratory experiments. In the future the unit will be used for clinical studies in the hospital and while transplantations or surgeries. Blood flow and pressure and body temperature will be measured non-invasively or using disposable transducers. More analytically the system will provide connections with a pressure sensor, two temperature sensors (Thermocouple and NTC), a flow sensor and moreover it will have a BNC Connector for measuring external signals from other medical devices. These are the basic connections but there will be a possibility of having more connectors and sensors according to the needs of the several customers. It will be powered by a low DC voltage through an AC/DC Adapter, and in that way it will provide electrical safety to the user against the hazards that can be caused by the high AC Voltages, as long as safety against damage of the electrical components of the device. The design of DatAssist will be based on the stakeholders such as surgeons, perfusionists and Organ Assist. Their preferences have been summarized in seven general requirements: reliability, quality, safety, ease of use, portability, purchase costs and CE Certified components. Moreover three more requirements were taken into account for the design of the several components: sterility (easy to sterilize components), modularity and ability of components to be used both inside blood and inside solutions. A function analysis demonstrated the most important functions of the DatAssist: sensing of the physical parameters (Pressure, Temperature, Flow), amplification of the analog input signal of the sensors, signal conditioning of the amplified signal, integration and processing of the digital signals with the help of a computer and display of the signal values in a monitor with the use of a Software program and a User interface. For each function, a certain procedure have been developed for defining its planning of implementation. This has resulted in the decision for which components to use in the final device after a scoring evaluation of the candidate components for each function based in their fulfillment to the mentioned above requirements. Additionally for each stage of the design defined by the functions, a functional model has been developed containing the final design of each stage and a test measuring its functionality and the reliability of measurements, as well as error measurements and an accuracy of the measurements estimation. Finally, a prototype of the DatAssist was engineered based on a design decided by the stakeholders having in mind to comply with the List of Requirements. This prototype is going to be tested for its accuracy of the measurements and evaluated according to its fulfillment of the list of requirements. With this study a proven reliable, sterile, portable, easy to use, safe for the user multi purpose medical Data Acquisition System is designed which can be purchased for less than €3000.
202

Dosimetria de filtros dinamicos aprimorados

SILVA, ROSIANE A. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:23Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
203

Desenvolvimento de conjunto detector cintilador com sistema de contagens e aquisicao de dados para medidas de vazao utilizando tracadores radioativos

COSTA, FABIO E. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:40Z (GMT). No. of bitstreams: 1 07178.pdf: 5559120 bytes, checksum: 99e8bb52573d489b59ca94f5400da04c (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
204

Desenvolvimento de um sistema computacional integrado para monitoramento de parâmetros físico-químicos da água e análise óptica de gotejadores / Development of an integrated computer system for monitoring physical and chemical parameters of water and optical analysis in drippers

Voltan, Diego Scacalossi [UNESP] 15 December 2015 (has links)
Submitted by DIEGO SCACALOSSI VOLTAN null (diegovoltan@fca.unesp.br) on 2016-02-03T15:36:27Z No. of bitstreams: 1 TESE_DIEGO_Print_Final4.pdf: 4460587 bytes, checksum: 4a85de599d1e27d4cbef2570809a0a67 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-02-05T11:55:42Z (GMT) No. of bitstreams: 1 voltan_ds_dr_bot.pdf: 4460587 bytes, checksum: 4a85de599d1e27d4cbef2570809a0a67 (MD5) / Made available in DSpace on 2016-02-05T11:55:42Z (GMT). No. of bitstreams: 1 voltan_ds_dr_bot.pdf: 4460587 bytes, checksum: 4a85de599d1e27d4cbef2570809a0a67 (MD5) Previous issue date: 2015-12-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho é uma pesquisa sobre a integração de sistemas computacionais na área de sensoriamento, incluindo o sensoriamento dos parâmetros físicoquímicos do ar e da água e a investigação de técnicas computacionais para medir a vazão de gotejadores com duas técnicas distintas, com registros de massa e a contagem de gotas por sistema óptico. Além disso, a integração permitiu o desenvolvimento de uma interface gráfica de comunicação homem-máquina capaz de mostrar os dados em tempo real e de forma amigável. Deste modo, o trabalho foi dividido em cinco módulos de desenvolvimento independentes, no entanto, inter-relacionados. No primeiro módulo, foi desenvolvido o sistema de monitoramento de parâmetros físicos do ar. No segundo, o sistema de automação do processo de aeração artificial da água do reservatório. No terceiro módulo, sistema de monitoramento de pesagem para bancada de ensaios. No quarto módulo, foi desenvolvido um sistema óptico de contagem de gotas. E, por final, a integração dos módulos anteriores em um único sistema, completando a quinta etapa do trabalho. O trabalho apresentou um resultado considerado satisfatório pois as medições realizadas em tempo real foram automaticamente armazenadas na forma de texto em um arquivo de dados que pode ser posteriormente importado por editores de texto e planilhas eletrônicas. A plataforma integrada é capaz de adquirir os dados de forma contínua durante vários dias de trabalho, baixas taxas de erros e fácil interação com o usuário. / This work presents a research on computer systems integration in the sensing area, including physical-chemical sensing parameters of air and water and computational techniques investigation to measure the flow emitters with two different techniques that are mass records and an optical drop counter. In addition, the integration allowed the development of a communication user graphical interface, which is able to display data in real time. Thus, this work was divided into five interrelated modules. In the first module, the system was developed for monitoring physical parameters of the air. Then, the automation system of the artificial aeration processes the reservoir water. In the third module, weighing monitoring system to test bench. In the fourth module, was developed a drop counter based on the optical system. By the end, the integration of the systems of previous modules into a single module, completing the fifth stage of the work. The work has presented a satisfactory outcome due to the measurements in real time were automatically stored as text in a data file that will be imported later into word processors and spreadsheets. The integrated platform is able to acquire the data for several days of work, with lower error rates and easy user interaction.
205

Desenvolvimento de um sistema de aquisição de dados georreferenciados e de telemetria para monitoramento de parâmetros físicos em sistemas de irrigação

Barbosa, Rogério Zanarde [UNESP] 16 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-16Bitstream added on 2014-06-13T20:34:40Z : No. of bitstreams: 1 barbosa_rz_me_botfca.pdf: 773098 bytes, checksum: 5e5761fb2f635f8660fde2f9e9b8bb08 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo deste projeto foi desenvolver um sistema para aquisição de dados georreferenciados e um sistema de telemetria para monitoramento de parâmetros físicos, aplicados em sistemas de irrigação e gestão de recursos hídricos. O sistema de aquisição de dados georreferenciados consiste em um software que realiza a aquisição de dados e o registro de informações georreferenciadas, a partir das informações recebidas de um dispositivo de sensoriamento escolhido pelo usuário e de um GPS, através da porta de comunicação serial RS-232 do computador. O software faz a aquisição de dados em tempo real, e então forma um único registro de dados com as informações do GPS e do dispositivo de sensoriamento, possibilitando a localização exata com data e hora onde foi realizada a medição da grandeza física. O sistema de telemetria para monitoramento de parâmetros físicos consiste no desenvolvimento de cinco softwares e um sistema de hardware para telemetria, incluindo um módulo transmissor e um receptor de rádio. Os softwares desenvolvidos são chamados de Software de Comunicação Serial, Software Registrador de Dados, Software para Testes de Rádio Transmissão, Software de Aquisição de Dados Georreferenciados e Software de Geração de Dados Físicos. O Software de Comunicação Serial estabelece a conexão serial e a consequente troca de informações entre duas máquinas ligadas por meio de um cabo metálico, através da porta de comunicação RS-232 dos computadores. O Software para Testes de Rádio Transmissão testa o alcance de transmissão de dados por rádio e é utilizado em sistemas de telemetria, permitindo verificar o alcance de transmissão de módulos de rádio frequência e o número de erros durante o processo de transmissão de dados... / This project goal is the development of a georeferenced data acquisition system and a telemetry system, both for physical parameters monitoring in irrigation and water management areas. The georeferenced data acquisition system is composed by software that perform the data acquisition and record of information received simultaneously through the serial interface RS232 from a sensing device and a GPS device. The software performs data acquisition in real time, and then composes a single data record with both the information, associating directly each physical measurement with its exact location, date and time. The telemetry system for physical parameters monitoring includes five pieces of software and two pieces of hardware for the radio transmitter and the radio receiver modules. The software system is composed by five different pieces of software called Serial Communications Software, Data Logger Software, Software for Radio Module Testing, Georeferenced Data Acquisition Software, Physical Data Generation Software. The Serial Communication Software establishes the wired serial connection and the subsequent exchange of information between two computers through the RS 232 computer interfaces. The Software for Radio Module Testing is a tool for the data radio transmission distance measurement and computation of the number of errors during the data transmission. The Data Logger Software allows the computer connection to any measuring instrument that has a physical serial communication output, then the software records data in a file on the computer disk. The Georeferenced Data Acquisition Software performs the data acquisition of physical parameters in georeferenced location using a measurement device and a GPS. The Physical Data Generation Software generates data according to the standard... (Complete abstract click electronic access below)
206

Desenvolvimento de sistema para seguimento de produto e aquisicao de dados do processo de irradiacao em irradiadores de grande porte / Development of system for product tracking and data acquisition of data irradiation process in large gamma irradiators

SOARES, JOSE R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:52:56Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:56Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
207

Desenvolvimento de um sistema de aquisição de dados georreferenciados e de telemetria para monitoramento de parâmetros físicos em sistemas de irrigação /

Barbosa, Rogério Zanarde, 1988. January 2012 (has links)
Orientador: João Eduardo Machado Perea Martins / Banca: João Carlos Cury Saad / Banca: Andréa Carla Gonçalves Vianna / Resumo: O objetivo deste projeto foi desenvolver um sistema para aquisição de dados georreferenciados e um sistema de telemetria para monitoramento de parâmetros físicos, aplicados em sistemas de irrigação e gestão de recursos hídricos. O sistema de aquisição de dados georreferenciados consiste em um software que realiza a aquisição de dados e o registro de informações georreferenciadas, a partir das informações recebidas de um dispositivo de sensoriamento escolhido pelo usuário e de um GPS, através da porta de comunicação serial RS-232 do computador. O software faz a aquisição de dados em tempo real, e então forma um único registro de dados com as informações do GPS e do dispositivo de sensoriamento, possibilitando a localização exata com data e hora onde foi realizada a medição da grandeza física. O sistema de telemetria para monitoramento de parâmetros físicos consiste no desenvolvimento de cinco softwares e um sistema de hardware para telemetria, incluindo um módulo transmissor e um receptor de rádio. Os softwares desenvolvidos são chamados de Software de Comunicação Serial, Software Registrador de Dados, Software para Testes de Rádio Transmissão, Software de Aquisição de Dados Georreferenciados e Software de Geração de Dados Físicos. O Software de Comunicação Serial estabelece a conexão serial e a consequente troca de informações entre duas máquinas ligadas por meio de um cabo metálico, através da porta de comunicação RS-232 dos computadores. O Software para Testes de Rádio Transmissão testa o alcance de transmissão de dados por rádio e é utilizado em sistemas de telemetria, permitindo verificar o alcance de transmissão de módulos de rádio frequência e o número de erros durante o processo de transmissão de dados... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This project goal is the development of a georeferenced data acquisition system and a telemetry system, both for physical parameters monitoring in irrigation and water management areas. The georeferenced data acquisition system is composed by software that perform the data acquisition and record of information received simultaneously through the serial interface RS232 from a sensing device and a GPS device. The software performs data acquisition in real time, and then composes a single data record with both the information, associating directly each physical measurement with its exact location, date and time. The telemetry system for physical parameters monitoring includes five pieces of software and two pieces of hardware for the radio transmitter and the radio receiver modules. The software system is composed by five different pieces of software called Serial Communications Software, Data Logger Software, Software for Radio Module Testing, Georeferenced Data Acquisition Software, Physical Data Generation Software. The Serial Communication Software establishes the wired serial connection and the subsequent exchange of information between two computers through the RS 232 computer interfaces. The Software for Radio Module Testing is a tool for the data radio transmission distance measurement and computation of the number of errors during the data transmission. The Data Logger Software allows the computer connection to any measuring instrument that has a physical serial communication output, then the software records data in a file on the computer disk. The Georeferenced Data Acquisition Software performs the data acquisition of physical parameters in georeferenced location using a measurement device and a GPS. The Physical Data Generation Software generates data according to the standard... (Complete abstract click electronic access below) / Mestre
208

Projeto e construção de sistema de aquisição e processamento de dados para espectroscopia por transformada rápida de Fourier / Project and building of data acquisition system for fast Fourier transform spectrometer.

Walter Soto Encinas Junior 03 April 1995 (has links)
No presente trabalho procurou-se desenvolver um sistema computacional para a automação de um Espectrofotômetro de Varredura Refrativa. Este sistema é baseado em um computador hospedeiro da linha IBM-PC, que pode ser de qualquer modelo, desde que possua barramento ISA de 16 bits. O sistema se divide em dois módulos - aquisição e processamento. O modulo de aquisição e capaz de atingir taxas de aquisição de ate 200 KHz, com resolução de 12 bits. É independente de controle do hospedeiro pois possui lógica de controle e sistema de armazenamento próprio. O módulo de processamento envolve o uso de um processador vetorial de sinais digitais ZORAN ZR34161 dedicado a efetuar eficientemente a Transformada Rápida de Fourier (FFT). Também opera independentemente do computador hospedeiro. Este módulo é capaz de efetuar a FFT em um vetor real de 4096 pontos em 19,64 ms / This work was intended to develop a computational system to control a fast Fourier spectrophotometer. This system is based in an IBM-PC type host computer, with ISA bus 16 bits wide. The system has two modules - acquisition and processing. The acquisition module works at 200 KHz sample rate, with 12 bits of resolution, and also works without host control, due to its own memory system and control logic. The processing module uses a ZORAN ZR34161 vector signal processor, dedicated to do the Fast Fourier Transform (FFT) in the most efficient way. No management of host is required, and it can compute a FFT of a 4096 points real vector in 19,64 ms
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Sistema Remoto de AquisiÃÃo e Monitoramento de VariÃveis Ambientais Para AplicaÃÃes de PrevisÃo MeteorolÃgica / System acquisition and remote monitoring of environmental variables for weather forecasting applications.

Thiago Pereira de Menezes 26 April 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / InÃmeras atividades do Homem tais como: agricultura, abastecimento humano, construÃÃo civil, defesa civil e turismo, estÃo fortemente ligados ao clima. Prever estiagem, chuvas e geadas leva a um controle que evita prejuÃzos financeiros e sociais. InformaÃÃes meteorolÃgicas sÃo de fundamental importÃncia para o monitoramento do clima e para previsÃo do tempo. O presente trabalho apresenta o projeto do hardware e do software de um sistema para aquisiÃÃo e monitoramento de informaÃÃes meteorolÃgicas, inspirado na necessidade de dados para o uso em tÃcnicas de redes neurais. O sistema à composto por estaÃÃes de campo, um servidor de dados remoto e estaÃÃes base. A primeira consiste de um microcontrolador que tem por funÃÃo principal coletar dados atravÃs de canais analÃgicos e digitais. Ele gerencia o uso da bateria de alimentaÃÃo, realiza conversÃes analÃgico-digitais proveniente dos sensores, salva as mediÃÃes em um banco de memÃria local, codifica e transmite os dados via internet para um servidor de dados. O segundo à um computador ligado à internet que possui um sistema de banco de dados onde os dados enviados pelas estaÃÃes base sÃo salvos em tabelas. Finalmente, a estaÃÃo base, consiste de um microcomputador convencional executando um software livre. O software supervisÃrio apresenta interface amigÃvel, possui recursos avanÃados de gerenciamento dos equipamentos, recursos de gerar grÃficos e relatÃrios e possui interaÃÃo com redes sociais (facebook/twitter). Foram desenvolvidos protÃtipos, um deles instalado nas dependÃncias do campus do Pici da Universidade Federal do CearÃ. CorrelaÃÃes e testes de desempenho sÃo usados para comparar os dados coletados pelo protÃtipo com os dados de um equipamento comercial. Os dados armazenados servem como fonte de informaÃÃo para alimentar redes neurais ou modelos que buscam a previsÃo do tempo. O sistema à totalmente configurÃvel e o monitoramento online dos parÃmetros ambientais possibilita gerar alertas de riscos de desastres. Hà a possibilidade do uso do sistema em larga escala para o monitoramento e aquisiÃÃo de dados em pontos estratÃgicos no estado do CearÃ. / Numerous human activities such as agriculture, human supply, civil construction, civil defense and tourism, are strongly linked to climate. Predicting drought, rain and frost leads to a predictive control that prevents financial losses and social. Weather information is of fundamental importance for climate monitoring and weather forecasting. This paper presents the design of hardware and software system for acquisition and tracking of meteorological information. The system consists of a field station, a remote database server and a base station. The field station consists of a microcontroller that collects primary data through analog and digital channels. It manages the use of battery power, performs analog-digital conversion from the sensors, the measurements saved in a local memory bank, encodes and transmits data via the Internet to a data server. The remote database server is a computer connected to the internet that has a database system which receives the data and saved in tables that can be accessed remotely by base stations. Finally, the base station consists of a conventional PC running a free software. The monitoring software provides user-friendly interface, advanced features for managing the equipment, resources to generate graphs and reports and has interaction with social networks (facebook / twitter). Prototypes were developed, one installed at Pici campus of Federal University of CearÃ. Correlations and performance tests are used to compare data collected by the prototype with data from a commercial equipment. The system is fully configurable and online monitoring of environmental parameters allows to generate a risk of disaster alerts. There is the possibility of using large-scale system for monitoring and data acquisition at strategic points in the state of CearÃ.
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Dosimetria de filtros dinamicos aprimorados

SILVA, ROSIANE A. da 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:23Z (GMT). No. of bitstreams: 0 / O objetivo deste trabalho foi realizar a dosimetria de filtros dinâmicos aprimorados (“Enhanced Dynamic Wedge” – EDW). Isso foi feito com dois intuitos: 1) a avaliação da implementação clínica do filtro dinâmico aprimorado considerando-se suas vantagens e desvantagens; e 2) a comparação entre a eficiência e a melhor aplicabilidade de três sistemas dosimétricos diferentes em conjunto com o filtro dinâmico aprimorado. Os sistemas dosimétricos utilizados foram: o Sistema de Imagem de Feixe (“Beam Image System” – BIS2G), da Scanditronix-Wellhöfer, uma câmara de ionização cilíndrica de 0,6 cm3 do tipo Farmer, e um arranjo linear de câmaras de ionização múltiplas (“Ionization Chamber Linear Detector Array”) com 23 câmaras de ionização cilíndricas de 0,14 cm3, tipo Farmer. Com o Sistema de Imagem de Feixe – BIS2G foi possível obter curvas de fluência que permitiram analisar a simetria dos perfis de fluência, linearidade da dose, efeito da taxa de dose e efeito da gravidade, características diretamente ligadas à qualidade do funcionamento do filtro dinâmico aprimorado, além de ter sido possível também calcular o fator filtro para campos simétricos. Com a câmara de ionização mediu-se a porcentagem de dose em profundidade - PDP e calculou-se o fator filtro para campos simétricos e campos assimétricos (uma das vantagens do EDW). Com o arranjo linear de câmaras de ionização múltiplas foi possível obter curvas de isodose que permitiram a verificação da simetria e a comparação com os resultados obtidos com o BIS2G, além do cálculo do fator filtro para campos simétricos. O fator filtro calculado através de medidas tomadas com os três sistemas foi também comparado com resultados obtidos por dois formalismos, de Gibbons1 e de Klein et al 2, bem conhecidos da literatura e que serviram para a validação dos resultados e deste trabalho. Destas comparações verificou-se que os ângulos do filtro dinâmico aprimorado que apresentam maior diferença entre resultados obtidos e os formalismos foram os ângulos de 45º e de 60º em relação ao método de Klein et al que apresentaram diferenças de 2,1% em relação ao BIS2G, 1,9% em relação à câmara de ionização e 1,1% em relação ao arranjo linear de câmaras de ionização. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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