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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.
81

Análise de desempenho do LoRa em aplicação de fiscalização eletrônica de veículos com RFID

Griese, Marcelo George January 2018 (has links)
Orientador: Prof. Dr. João Henrique Kleinschmidt / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia da Informação, Santo André, 2018. / Em 2006 o governo brasileiro instituiu o sistema nacional de identificação automática de veículos (SINIAV), cujo objetivo principal é fiscalizar todos os veículos através da tecnologia de identificação por rádio frequência (RFID). Entretanto, esse projeto tem um grande desafio tecnológico com relação a conectividade e transmissão de dados quando aplicado dentro das cidades, o que pode dificultar sua escalabilidade. Por isso, o objetivo dessa dissertação é estudar a viabilidade técnica do uso do LoRa para a transmissão dos dados provenientes da fiscalização eletrônica de veículos através de RFID. Então, uma análise de desempenho de um sistema composto por uma antena RFID, para realizar as leituras das tags, e um transmissor LoRa, para enviar essas leituras a um gateway conectado à internet, foi realizado e as métricas de taxa de perda de pacotes (PER) e taxa de envio de pacotes (throughput) da transmissão do LoRa foram medidas. Os resultados obtidos mostraram que em determinados cenários é possível obter uma taxa de perda de pacotes abaixo de 20% e uma taxa de envio de pacotes acima de 60 envios por minuto, o que torna o uso do LoRa uma tecnologia viável para essa aplicação de fiscalização e outras aplicações relacionadas à sistemas inteligentes de transporte (ITS). / In 2006, the Brazilian government instituted the national system of automatic vehicle identification (SINIAV), whose main objective is to control all vehicles through radio frequency identification (RFID) technology. However, this project has a great technological challenge regarding connectivity and data transmission when applied within cities, which may hinder its scalability. Therefore, the objective of this dissertation is to study the technical feasibility of the use of LoRa for the transmission of data from the electronic surveillance of vehicles through RFID. Then, a performance analysis of a system composed of an RFID antenna to perform the readings of the tags and a LoRa transmitter to send those readings to a gateway connected to the Internet was performed and the packet loss rate metrics (PER) and LoRa transmission throughput rates were measured. The results show that in certain scenarios it is possible to obtain a packet loss rate of less than 20% and a packet sending rate of more than 60 packets per minute, which makes the use of LoRa a viable technology for this enforcement application and other applications related to Intelligent Transport Systems (ITS).
82

Zařízení pro zaznamenávání proudové spotřeby LPWA senzorů / Design of a current data logger for LPWA sensors

Mikulášek, Michal January 2020 (has links)
This Master thesis deals with the design and construction of a measuring device for measuring and the current consumption logging of sensors using LPWAN (Low Power Wide Area Network) technology. The theoretical part of the thesis firstly summarizes selected LPWAN technologies. Selected technologies, namely: LoRaWAN, Sigfox and Narrowband IoT (NB-IoT), are described more in detail. Further, the current measurement techniques are briefly discussed. The main focus is given to the current shunt measuring methods. The second half of thesis describes procedures conducted during the design and construction of a measuring device. The current measuring is based on the current shunt circuit complemented by the voltage amplification circuit, whose output is subsquently converted into digital form using an AD converter. The thesis describes in great detail the procedures for selecting individual components and important processes used in design of printed circuit boards. An integral part of the measuring device implementation is the design and implementation of control software, which is described in detail and supplemented by workflow charts underlining the entire description. The implementation of the entire measuring device is completed by the design and implementation of the cover box using 3D printing technology. Finally, the specifications of designed device are briefly discussed based on the limits of the used components.
83

IIoT-based Instrumentation and Control System for a Lateral Micro-drilling Robot Using Machine Fault Diagnosis and Failure Prognosis

Jose A. Solorio Cervantes (11191893) 11 October 2023 (has links)
<p dir="ltr">This project aimed to develop an instrumentation and control system for a micro-drilling robot based on Industrial Internet of Things (IIoT) technologies. The automation system integrated IIoT technological tools to create a robust automation system capable of being used in drilling operations. The system incorporated industrial-grade sensors, which carried out direct measurements of the critical variables of the process. The indirect variables relevant to the control of the robot were calculated from the measured parameters. The system also considered the telemetry architecture necessary to reliably transmit data from the down-the-hole (DTH) robot to a receiver on the surface. Telemetry was based on wireless communication through long-range radio frequency (LoRa). The system developed had models based on Artificial Intelligence (AI) and Machine Learning (ML) for determining the mode of operation, detecting changes in the process, and changes in drilling variables in critical hydraulic components for the drilling process. Algorithms based on AI and ML models also allowed the user to make better decisions based on the variables' correlation to optimize the drilling process (e.g., dynamic change of flow, pressure, and RPMs based on automatic rock identification). A user interface (UI) was developed, and digital tools to perform data analysis were implemented. Safety assessment in all robot systems (e.g., electrical, hardware, software) was contemplated as a critical design component. The result of this research project provides innovative micro-drilling robots with the necessary technological tools to optimize the drilling process. The system made drilling more efficient, reliable, and safe, providing diagnostic and prognostic tools that allowed planning maintenance based on the actual health of the devices. The system that was developed was tested in a test bench under controlled conditions within a laboratory to characterize the system and collect data that allowed ML models' development, training, validation, and testing. The prototype of a micro-drilling robot installed on the test bench served as a case study to assess the implemented models' reliability and the proposed telemetry.</p>
84

Site-specificity in The educators new clothes by Mark Rautenbach / Mošomo ya bokgabo ya ka lefelong le itšego ka go bkogabo bjo bo bitšwago The educators new clothes ka Mark Rautenbach / Plekspesifisiteit in The educator's new clothes deur Mark Rautenbach

Cloete, Zelda 12 1900 (has links)
Text in English, with summaries and keywords in English, Sesotho and Afrikaans / This study is an enquiry into how The educator’s new clothes by Mark Rautenbach is an example of site-specific art. The aim is to demonstrate how boundaries in TENC become blurred between site-specific performance, other art forms, and every-day activities. The key concepts explored are: Rautenbach’s approach to the concept of site, the connections that develop between his performance and each site that he travels to; his use of the art gallery and viewer participation. Through literature study relevant theory is explored, and several arguments are applied in a selective manner to my analysis of TENC. Various International and South African site-specific artworks are discussed as an indication of how site-specificity can be applied in alternative ways. In October 2017 I installed GREENER?, a site-specific exhibition in the UNISA Art gallery. The works on the show underline the theoretical findings and highlight the flexible application of theory relating to site-specificity. / Dinyakišišo tše ke phatišišo mabapi le seo se dirago bokgabo bja The educator’s new clothes (TENC) ka Mark Rautenbach go ba mohlala wa bokgabo bja lefelong le itšego. Maikemišetšo ke go laetša ka fao ka go TENC mellwane magareng ga mošomo wa ka lefelong le mehuta ye mengwe ya bokgabo le mediro ya ka mehla di thomago go se sa bonagala gabotse. Mareo ao a šomišwago ke: mokgwa wa Rautenbach go kgopolo ya lefelo, dikgokagano tše di hlamegago magareng ga phethagatšo ya ya gagwe ya mošomo le lefelo le lengwe le le lengwe leo a yago go lona, tšhomišo ya gagwe ya kalari ya tša bokgabo le go kgatha tema ga babogedi. Ka go diriša dingwalwa teori ya maleba e a utollwa, gomme dintlha tše mmalwa di a dirišwa ka mokgwa wa go kgetha go tshekatsheko ya ka ya TENC. Mešomo ya bokgabo ya ka lefelong le itšego ya mehutahuta e a ahlaahlwa bjalo ka kutollo ya ka fao bokgabo bja ka mafelong bo ka dirišwago ka ditsela tše dingwe. Ka Oktoboro 2017 ke hlomile GREENER?, e lego pontšho ya bokgabo ya ka lefelong le itšego, ka Kalaring ya Bokgabo ya ka Unisa. Mešomo ye e bontšhitšwego e laeditše dikutollo tša teori le go laetša tirišo ye e fetogago ya teori mabapi le mešomo ya bokgabo ya ka lefelong le itšego. / Hierdie studie behels ʼn ondersoek na wat van The educator’s new clothes (TENC) deur Mark Rautenbach plekspesifieke kuns maak. Die oogmerk is om aan te toon hoe die grense tussen plekspesifieke uitvoering, ander kunsvorme en daaglikse bedrywighede vervaag. Die kernkonsepte wat verken word, is Rautenbach se beskouing van die konsep van plek, die verband tussen sy uitvoering en elke plek waarheen hy reis, sy aanwending van ʼn kunsgalery, en kykerdeelname. Die tersaaklike teorie word aan die hand van ʼn literatuurstudie verken, en ʼn aantal argumente word op selektiewe wyse op my ontleding van TENC toegepas. Verskeie internasionale en Suid-Afrikaanse plekspesifieke kunswerke word bespreek as ʼn verkenning van hoe plekspesifisiteit op ander maniere toegepas word. Ek het in Oktober 2017 ʼn plekspesifieke uitstalling met die titel GREENER? in die Unisa Kunsgalery gehou. Die werke wat uitgestal is, onderstreep die teoretiese bevindings en vestig die aandag op die buigsame toepassing van die teorie in verband met plekspesifisiteit. / Art History, Visual Arts and Musicology / M.V.A.

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