Towards the development of a smartphone-based biosensor for detecting Tuberculosis

Date
2024-03
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Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Detecting underperforming solar photovoltaic (PV) modules in large-scale installations is challenging, with over 25% of operations and maintenance costs stemming from inefficient maintenance. It is therefore crucial to detect problems within a PV installation as early as possible. This research project has developed an improved wireless monitoring system to enable timely diagnostics and future adaptability, addressing limitations in existing PV monitoring solutions. The implemented system consists of plug-and-play smart field nodes (SFN), a full-duplex gateway, and a web application. A listen before talk communication protocol is implemented to allow for network scalability. Furthermore, a new approach to developing modular, scalable firmware using the active object programming paradigm is introduced. SFNs periodically sample PV panel electrical parameters, temperatures, and battery voltage with a minimum accuracy of 0.68% for voltage, 5% for current, and ±0.5◦C for temperature. The data is encrypted using AES-128 and transmitted to the gateway via LoRa packets. The web application provides an intuitive interface to view real-time and historical SFN data for each PV panel. Field-testing exhibited good measurement accuracy and a 93% packet delivery rate across SFNs. The scalability for over 10 simultaneously communicating SFNs was successfully demonstrated, and further work includes improving the positional accuracy. In summary, the secure smart monitoring system successfully addressed key limitations in existing solutions through enhanced firmware modularity, easier installation, and an accurate universal modular system adaptable for future research. The accuracy and reliability exhibited in preliminary testing validates its potential for use in future solar PV research and development projects.
AFRIKAANSE OPSOMMING: Die opsporing van onderpresterende sonkrag fotovolta¨ıese (PV) modules in grootskaalse installasies is uitdagend, met meer as 25% van bedryfs- en onderhoudskoste wat voortspruit uit ondoeltreffende onderhoud. Dit is daarom noodsaaklik om probleme binne ’n PV-installasie so vroeg as moontlik op te spoor. Hierdie navorsingsprojek het ’n verbeterde draadlose moniteringstelsel ontwikkel om tydige diagnostiek en toekomstige aanpassings moontlik te maak, en spreek beperkinge in bestaande PV-moniteringsoplossings aan. Die ge¨ımplementeerde stelsel bestaan uit prop-en-speel slimveldnodes (SVNs), ’n vol-dupleks poort (gateway), en ’n webtoepassing. ’n Luister-voor-jy-praat kommunikasieprotokol om netwerkskaalbaarheid toe te laat, is ge¨ımplementeer. Verder word ’n nuwe benadering tot die ontwikkeling van modulˆere, skaalbare firmware met behulp van die aktiewe voorwerp programmerings-argitektuur bekendgestel. SVNs neem periodiek metings van die PV-paneel elektriese parameters, temperature, en SVN batteryspanning met ’n minimum akkuraatheid van 0.68% vir spanning, 5% vir stroom, en ±0.5◦C vir temperatuur. Die data word met behulp van AES-128 ge¨ınkripteer en na die poort via LoRa-pakkette oorgedra. Die webtoepassing bied ’n intu¨ıtiewe blad om huidige en historiese SVN data vir elke PV-paneel te toon. Veldtoetsing het goeie meetakkuraatheid getoon en ’n 93% pakketafleweringstempo oor SVNs. Die skaalbaarheid vir meer as 10 SVNs wat gelyktydig kommunikeer is bevestig, en verdere werk sluit in die verbetering van die posisionele akkuraatheid. Ter opsomming, die veilige slim moniteringstelsel het sleutelbeperkinge in bestaande oplossings suksesvol aangespreek deur verbeterde firmware modulariteit, makliker installasie en ’n akkurate universele modulˆere sisteem wat aanpasbaar is vir toekomstige navorsing. Die betroubaarheid wat getoon is in voorlopige toetsing, bevestig die potensi¨ele gebruike daarvan in toekomstige sonkrag PV-navorsing-en-ontwikkelings projekte.
Description
Thesis (MEng)--Stellenbosch University, 2024.
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