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Enhanced Approach for the Classification of Ulcerative Colitis Severity in Colonoscopy Videos Using CNNSure, Venkata Leela 08 1900 (has links)
Ulcerative colitis (UC) is a chronic inflammatory disease characterized by periods of relapses and remissions affecting more than 500,000 people in the United States. To achieve the therapeutic goals of UC, which are to first induce and then maintain disease remission, doctors need to evaluate the severity of UC of a patient. However, it is very difficult to evaluate the severity of UC objectively because of non-uniform nature of symptoms and large variations in their patterns. To address this, in our previous works, we developed two different approaches in which one is using the image textures, and the other is using CNN (convolutional neural network) to measure and classify objectively the severity of UC presented in optical colonoscopy video frames. But, we found that the image texture based approach could not handle larger number of variations in their patterns, and the CNN based approach could not achieve very high accuracy. In this paper, we improve our CNN based approach in two ways to provide better accuracy for the classification. We add more thorough and essential preprocessing, and generate more classes to accommodate large variations in their patterns. The experimental results show that the proposed preprocessing can improve the overall accuracy of evaluating the severity of UC.
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Refinement of Raman spectra from extreme background and noise interferences: Cancer diagnostics using Raman spectroscopyGebrekidan, Medhanie Tesfay 01 March 2022 (has links)
Die Raman-Spektroskopie ist eine optische Messtechnik, die in der Lage ist, spektroskopische Information zu liefern, welche molekülspezifisch und einzigartig in Bezug auf die Eigenschaften der untersuchten Spezies sind. Sie ist ein unverzichtbares analytisches Instrument, das Anwendung in verschiedenen Bereichen findet, wie etwa der Medizin oder der in situ Beobachtung von chemischen Prozessen. Wegen ihren Eigenschaften, wie der hohen Spezifität und der Möglichkeit von Tracer-freien Messung, hat die Raman-Spektroskopie die Tumordiagnostik stark beeinflusst. Aufgrund einer äußerst starken Beeinflussung der Raman-Spektren durch Hintergrundsignale, ist das Isolieren und Interpretieren von Raman-Spektren eine große Herausforderung.
Im Rahmen dieser Arbeit wurden verschiedene Ansätze der Spektrenbearbeitung entwickelt, die benötigt werden um Raman-Spektren aus verrauschten und stark mit Hintergrundsignalen behafteten Rohspektren zu extrahieren. Diese Ansätze beinhalten im Speziellen eine auf dem Vector-Casting basierende Methode zur Rauschminimierung und eine auf dem deep neural networks basierende Methoden zur Entfernung von Rauschen und Hintergrundsignalen. Verschiedene neuronale Netze wurden mittels simulierter Spektren trainiert und an experimentell gemessenen Spektren evaluiert. Die im Rahmen dieser Arbeit vorgeschlagenen Ansätze wurden mit alternativen Methoden auf dem aktuellen Stand der Entwicklung unter Zuhilfenahme von verschiedenen Signal-Rausch-Verhältnissen, Standardabweichungen und dem Structural Similarity Index verglichen. Die hier entwickelten Ansätze zeigen gute Ergebnisse und sind bisher bekannten Methoden überlegen, vor allem für Raman-Spektren mit einem niedrigem Signal-Rausch-Verhältnis und extrem starken Fluoreszenz-Hintergrund. Zusätzlich erfordern die auf Deep Neural Networks basierten Methoden keinerlei menschliches Eingreifen.
Die Motivation hinter dieser Arbeit ist die Verbesserung der Raman-Spektroskopie, vor allem der Shifted-Excitation Raman Difference Spectroscopy (SERDS) hin zu einem noch besseren Instrument in der Prozessanalytik und Tumordiagnostik. Die Integration der oben genannten Ansätze zur Spektrenbearbeitung von SERDS in Kombination mit Methoden des maschinellen Lernens ermöglichen es, physiologische Schleimhaut, nicht-maligne Läsionen und orale Plattenepithelkarzinome mit einer Genauigkeit zu unterscheiden, die bisherigen Methoden überlegen ist.
Die spezifischen Merkmale in den bearbeiteten Raman-Spektren können verschiedenen chemischen Zusammensetzungen in den jeweiligen Geweben zugeordnet werden. Die Übertragbarkeit auf einen ähnlichen Ansatz zur Erkennung von Brusttumoren wurde überprüft.
Die bereinigten Raman-Spektren von normalem Brustgewebe, Fibroadenoma und invasiven Mammakarzinom konnten mithilfe der spektralen Eigenschaften von Proteinen, Lipiden und Nukleinsäuren unterschieden werden. Diese Erkenntnisse lassen das Potential von SERDS in Kombination mit Ansätzen des maschinellen Lernens als universelles Werkzeug zur Tumordiagnose erkennen.:Versicherung
Abstract
Zusammenfassung der Ergebnisse der Dissertation
Table of Contents
Abbreviations and symbols
1 Introduction
2 State of the art of the purification of Raman spectra
2.1 Experimental methods for the enhancement of the signal-to-background ratio and the signal-to-noise ratio
2.2 Mathematical methods for the extraction of pure Raman spectra from raw spectra
2.3 Raman based cancer diagnostics
2.4 Neural networks for the evaluation of Raman spectra
2.5 Objective
3 Application relevant fundaments
3.1 Basics of Raman spectroscopy
3.2 Simulation of raw Raman spectra
3.3 Shifted-excitation Raman difference Spectroscopy
3.4 Raman experimental setup
3.5 Mathematical method for Raman spectra refinement
3.6 Deep neural networks
4 Summary of the published results
4.1 A shifted-excitation Raman difference spectroscopy evaluation strategy for the efficient isolation of Raman spectra from extreme fluorescence interference
4.2 Vector casting for noise reduction
4.3 Refinement of spectra using a deep neural network; fully automated removal of noise and background
4.4 Breast Tumor Analysis using Shifted Excitation Raman difference Spectroscopy
4.5 Optical diagnosis of clinically apparent lesions of oral cavity by label free Raman spectroscopy
Conclusion / Raman spectroscopy is an optical measurement technique able to provide spectroscopic information that is molecule-specific and unique to the nature of the specimen under investigation. It is an invaluable analytical tool that finds application in several fields such as medicine and in situ chemical processing. Due to its high specificity and label-free features, Raman spectroscopy greatly impacted cancer diagnostics. However, retrieving and interpreting the Raman spectrum that contains the molecular information is challenging because of extreme background interference.
I have developed various spectra-processing approaches required to purify Raman spectra from noisy and heavily background interfered raw Raman spectra. In detail, these are a new noise reduction method based on vector casting and new deep neural networks for the efficient removal of noise and background. Several neural network models were trained on simulated spectra and then tested with experimental spectra. The here proposed approaches were compared with the state-of-the-art techniques via different signal-to-noise ratios, standard deviation, and the structural similarity index metric. The methods presented here perform well and are superior in comparison to what has been reported before, especially at small signal-to-noise ratios, and for extreme fluorescence interfered raw Raman spectra. Furthermore, the deep neural network-based methods do not rely on any human intervention.
The motivation behind this study is to make Raman spectroscopy, especially the shifted-excitation Raman difference spectroscopy (SERDS), an even better tool for process analytics and cancer diagnostics. The integration of the above-mentioned spectra-processing approaches into SERDS in combination with machine learning tools enabled the differentiation between physiological mucosa, non-malignant lesions, and oral squamous cell carcinomas with high accuracy, above the state of the art. The distinguishable features obtained in the purified Raman spectra are assignable to different chemical compositions of the respective tissues. The feasibility of a similar approach for breast tumors was also investigated. The purified Raman spectra of normal breast tissue, fibroadenoma, and invasive carcinoma were discriminable with respect to the spectral features of proteins, lipids, and nucleic acid. These findings suggest the potential of SERDS combined with machine learning techniques as a universal tool for cancer diagnostics.:Versicherung
Abstract
Zusammenfassung der Ergebnisse der Dissertation
Table of Contents
Abbreviations and symbols
1 Introduction
2 State of the art of the purification of Raman spectra
2.1 Experimental methods for the enhancement of the signal-to-background ratio and the signal-to-noise ratio
2.2 Mathematical methods for the extraction of pure Raman spectra from raw spectra
2.3 Raman based cancer diagnostics
2.4 Neural networks for the evaluation of Raman spectra
2.5 Objective
3 Application relevant fundaments
3.1 Basics of Raman spectroscopy
3.2 Simulation of raw Raman spectra
3.3 Shifted-excitation Raman difference Spectroscopy
3.4 Raman experimental setup
3.5 Mathematical method for Raman spectra refinement
3.6 Deep neural networks
4 Summary of the published results
4.1 A shifted-excitation Raman difference spectroscopy evaluation strategy for the efficient isolation of Raman spectra from extreme fluorescence interference
4.2 Vector casting for noise reduction
4.3 Refinement of spectra using a deep neural network; fully automated removal of noise and background
4.4 Breast Tumor Analysis using Shifted Excitation Raman difference Spectroscopy
4.5 Optical diagnosis of clinically apparent lesions of oral cavity by label free Raman spectroscopy
Conclusion
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Deep Learning för klassificering av kundsupport-ärendenJonsson, Max January 2020 (has links)
Företag och organisationer som tillhandahåller kundsupport via e-post kommer över tid att samla på sig stora mängder textuella data. Tack vare kontinuerliga framsteg inom Machine Learning ökar ständigt möjligheterna att dra nytta av tidigare insamlat data för att effektivisera organisationens framtida supporthantering. Syftet med denna studie är att analysera och utvärdera hur Deep Learning kan användas för att automatisera processen att klassificera supportärenden. Studien baseras på ett svenskt företags domän där klassificeringarna sker inom företagets fördefinierade kategorier. För att bygga upp ett dataset extraherades supportärenden inkomna via e-post (par av rubrik och meddelande) från företagets supportdatabas, där samtliga ärenden tillhörde en av nio distinkta kategorier. Utvärderingen gjordes genom att analysera skillnaderna i systemets uppmätta precision då olika metoder för datastädning användes, samt då de neurala nätverken byggdes upp med olika arkitekturer. En avgränsning gjordes att endast undersöka olika typer av Convolutional Neural Networks (CNN) samt Recurrent Neural Networks (RNN) i form av både enkel- och dubbelriktade Long Short Time Memory (LSTM) celler. Resultaten från denna studie visar ingen ökning i precision för någon av de undersökta datastädningsmetoderna. Dock visar resultaten att en begränsning av den använda ordlistan heller inte genererar någon negativ effekt. En begränsning av ordlistan kan fortfarande vara användbar för att minimera andra effekter så som exempelvis träningstiden, och eventuellt även minska risken för överanpassning. Av de undersökta nätverksarkitekturerna presterade CNN bättre än RNN på det använda datasetet. Den mest gynnsamma nätverksarkitekturen var ett nätverk med en konvolution per pipeline som för två olika test-set genererade precisioner på 79,3 respektive 75,4 procent. Resultaten visar också att några kategorier är svårare för nätverket att klassificera än andra, eftersom dessa inte är tillräckligt distinkta från resterande kategorier i datasetet. / Companies and organizations providing customer support via email will over time grow a big corpus of text documents. With advances made in Machine Learning the possibilities to use this data to improve the customer support efficiency is steadily increasing. The aim of this study is to analyze and evaluate the use of Deep Learning methods for automizing the process of classifying support errands. This study is based on a Swedish company’s domain where the classification was made within the company’s predefined categories. A dataset was built by obtaining email support errands (subject and body pairs) from the company’s support database. The dataset consisted of data belonging to one of nine separate categories. The evaluation was done by analyzing the alteration in classification accuracy when using different methods for data cleaning and by using different network architectures. A delimitation was set to only examine the effects by using different combinations of Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN) in the shape of both unidirectional and bidirectional Long Short Time Memory (LSTM) cells. The results of this study show no increase in classification accuracy by any of the examined data cleaning methods. However, a feature reduction of the used vocabulary is proven to neither have any negative impact on the accuracy. A feature reduction might still be beneficial to minimize other side effects such as the time required to train a network, and possibly to help prevent overfitting. Among the examined network architectures CNN were proven to outperform RNN on the used dataset. The most accurate network architecture was a single convolutional network which on two different test sets reached classification rates of 79,3 and 75,4 percent respectively. The results also show some categories to be harder to classify than others, due to them not being distinct enough towards the rest of the categories in the dataset.
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Klassificering av kvitton med hjälp av maskininlärningEnerstrand, Simon January 2019 (has links)
Maskininlärning nyttjas inom fler och fler områden. Det har potential att ersätta många repetitiva arbetsuppgifter, eller åtminstone förenkla dem. Dokumenthantering inom ekonomisystem är ett område maskininlärning kan hjälpa till med. Det behövs ofta mycket manuell input i olika fält genom att avläsa fakturor eller kvitton. Målet med projektet är att skapa en applikation som nyttjar maskininlärning åt företaget Centsoft AB. Applikationen ska ta emot OCR-tolkad textmassa från en bild på ett kvitto och sedan, med hög säkerhet, kunna avgöra vilken kategori kvittot tillhör. Den här rapporten syftar till att visa utvecklingen av maskininlärningsmodellen i applikationen. Rapporten svarar på frågeställningen: ”Hur kan kvitton klassificeras med hjälp av maskininlärning?”.Undersökningsmetoden fallstudie och projektmetoden MoSCoW tillämpas i projektet. Projektet tar även hänsyn till åtagandetriangeln. Maskininlärningsramverk används för att utvärdera den upptränade modellen. Den tränade modellen klarar av att, med hög säkerhet, tolka kvitton den inte stött på tidigare. För att få en meningsfull tolkning måste kvitton ha i avsikt att tillhöra någon av de åtta tränade kategorierna.Valet av metoder passade bra till projektet för att besvara frågeställningen. Applikationen kan utvecklas vidare och implementeras i fakturahanteringssystemet. Genomförandet av projektet ger kunskap att arbeta med maskininlärningslösningar. Tekniken kan i framtiden appliceras på flera områden. / Machine learning is used in more and more areas. It has the potential to replace many repetitive tasks, or at least simplify them. Document management within financial systems is an area machine learning can help with. A lot of manual input is often needed in different fields by reading invoices or receipts. The goal of the project is to create an application that uses machine learning for the company Centsoft AB. The application should receive OCR-interpreted texts from an image of a receipt and then, with high certainty, be able to determine which category the receipt belongs to. This report aims to show the development of the machine learning model in the application. The report answers the question: "How can receipts be classified using machine learning?".The methodology case study and the research method MoSCoW will be applied during the project. The project also considers the triangle method described by Eklund. Machine learning frameworks are used to evaluate the trained model. The trained model can, with high certainty, interpret receipts it has not encountered before. In order to get a meaningful interpretation, receipts must have the intention of belonging to one of the eight trained categories.The choice of methods suited the project well to answer the question. The application can be further developed and be implemented in the invoice management system. The implementation of the project gives knowledge about how to work with machine learning solutions. In the future, the technology can be applied in several areas.
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Monitoring Bicycle Safety through GPS data and Deep Learning Anomaly DetectionYaqoob, Shumayla, Cafiso, Salvatore, Morabito, Giacomo, Pappalardo, Giuseppina 02 January 2023 (has links)
Cycling has always been considered a sustainable and healthy mode of transport. Moreover, during Covid-19 period, cycling was further appreciated. by citizens as an individual opportunity of mobility. As a counterpart of the growth in the num.ber ofbicyclists and of riding k:ilometres, bicyclist safety has become a challenge as the unique road transport mode with an increasing trend of crash fatalities in EU (Figure 1).
When compared to the traditional road safety network screening. availability of suitable data for crashes involving bicyclists is more difficult because of underreporting and traffic flow issues. In such framework, new technologies and digital transformation in smart cities and communities is offering new opportunities of data availability which requires also different approaches for collection and analysis. An experimental test was carried out to collect data ftom different users with an instrumented bicycle equipped with Global Navigation Satellite Systems (GNSS) and cameras. A panel of experts was asked to review the collected data to identify and score the severity of the safety critical events (CSE) reaching a good consensus. Anyway, manual observation and classi.fication of CSE is a time consu.ming and unpractical approach when large amount of data must be analysed. Moreover, due to the complex correlation between precrash driving behaviour and due to high dimensionality of the data, traditional statistical methods might not be appropriate in t.bis context. Deep learning-based model have recently gained significant attention in the lit.erature for time series data analysis and for anomaly detection, but generally applied to vehicles' mobility and not to micro-mobility.
We present and discuss data requirements and treatment to get suitable infonnation from the GNSS devices, the development of an experimental :framework: where convolutional neural networks (CNN) is applied to integrate multiple GPS data streams of bicycle kinematics to detect the occurrence of a CSE.
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Jämförelse av artificiella neurala nätverksalgoritmerför klassificering av omdömen / Comparing artificial neural network algorithms forclassification of reviewsGilljam, Daniel, Youssef, Mario January 2018 (has links)
Vid stor mängd data i form av kundomdömen kan det vara ett relativt tidskrävande arbeteatt bedöma varje omdömes sentiment manuellt, om det är positivt eller negativt laddat. Denna avhandling har utförts för att automatiskt kunna klassificera kundomdömen efter positiva eller negativa omdömen vilket hanterades med hjälp av maskininlärning. Tre olika djupa neurala nätverk testades och jämfördes med hjälp av två olika ramverk, TensorFlow och Keras, på både större och mindre datamängder. Även olika inbäddningsmetoder testades med de neurala nätverken. Den bästa kombination av neuralt nätverk, ramverk och inbäddningsmetod var ett Convolutional Neural Network (CNN) som använde ordinbäddningsmetoden Word2Vec, var skriven i ramverket Keras och gav en träffsäkerhetpå ca 88.87% med en avvikelse på ca 0.4%. CNN gav bäst resultat i alla olika tester framför de andra två neurala nätverken, Recurrent Neural Network (RNN) och Convolutional Recurrent Neural Network (CRNN) / With large amount of data in the form of customer reviews, it could be time consuming to manually go through each review and decide if its sentiment is positive or negative. This thesis have been done to automatically classify client reviews to determine if a review is positive or negative. This was dealt with by machine learning. Three different deep neural network was tested on greater and lesser datasets, and compared with the help of two different frameworks, TensorFlow and Keras. Different embedding methods were tested on the neural networks. The best combination of a neural network, a framework and anembedding was the Convolutional Neural Network (CNN) which used the word embedding method Word2Vec, was written in Keras framework and gave an accuracy of approximately 88.87% with a deviation of approximately 0.4%. CNN scored a better result in all of the tests in comparison with the two other neural networks, Recurrent NeuralNetwork (RNN) and Convolutional Recurrent Neural Network (CRNN).
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Impact of data augmentations when training the Inception model for image classificationBarai, Milad, Heikkinen, Anthony January 2017 (has links)
Image classification is the process of identifying to which class a previously unobserved object belongs to. Classifying images is a commonly occurring task in companies. Currently many of these companies perform this classification manually. Automated classification however, has a lower expected accuracy. This thesis examines how automated classification could be improved by the addition of augmented data into the learning process of the classifier. We conduct a quantitative empirical study on the effects of two image augmentations, random horizontal/vertical flips and random rotations (<180◦). The data set that is used is from an auction house search engine under the commercial name of Barnebys. The data sets contain 700 000, 50 000 and 28 000 images with each set containing 28 classes. In this bachelor’s thesis, we re-trained a convolutional neural network model called the Inception-v3 model with the two larger data sets. The remaining set is used to get more class specific accuracies. In order to get a more accurate value of the effects we used a tenfold cross-validation method. Results of our quantitative study shows that the Inception-v3 model can reach a base line mean accuracy of 64.5% (700 000 data set) and a mean accuracy of 51.1% (50 000 data set). The overall accuracy decreased with augmentations on our data sets. However, our results display an increase in accuracy for some classes. The highest flat accuracy increase observed is in the class "Whine & Spirits" in the small data set where it went from 42.3% correctly classified images to 72.7% correctly classified images of the specific class. / Bildklassificering är uppgiften att identifiera vilken klass ett tidigare osett objekt tillhör. Att klassificera bilder är en vanligt förekommande uppgift hos företag. För närvarande utför många av dessa företag klassificering manuellt. Automatiserade klassificerare har en lägre förväntad nogrannhet. I detta examensarbete studeradas hur en maskinklassificerar kan förbättras genom att lägga till ytterligare förändrad data i inlärningsprocessen av klassificeraren. Vi genomför en kvantitativ empirisk studie om effekterna av två bildförändringar, slumpmässiga horisontella/vertikala speglingar och slumpmässiga rotationer (<180◦). Bilddatasetet som används är från ett auktionshus sökmotor under det kommersiella namnet Barnebys. De dataseten som används består av tre separata dataset, 700 000, 50 000 och 28 000 bilder. Var och en av dataseten innehåller 28 klasser vilka mappas till verksamheten. I det här examensarbetet har vi tränat Inception-v3-modellen med dataset av storlek 700 000 och 50 000. Vi utvärderade sedan noggrannhet av de tränade modellerna genom att klassificera 28 000-datasetet. För att få ett mer exakt värde av effekterna använde vi en tiofaldig korsvalideringsmetod. Resultatet av vår kvantitativa studie visar att Inceptionv3-modellen kan nå en genomsnittlig noggrannhet på 64,5% (700 000 dataset) och en genomsnittlig noggrannhet på 51,1% (50 000 dataset). Den övergripande noggrannheten minskade med förändringar på vårat dataset. Dock visar våra resultat en ökad noggrannhet i vissa klasser. Den observerade högsta noggrannhetsökningen var i klassen Åhine & Spirits", där vi gick från 42,3 % korrekt klassificerade bilder till 72,7 % korrekt klassificerade bilder i det lilla datasetet med förändringar.
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Straight to the Heart : Classification of Multi-Channel ECG-signals using MiniROCKET / Direkt till hjärtat: Klassifiering av fler-kanals EKG med MiniROCKETChristiansson, Stefan January 2023 (has links)
Machine Learning (ML) has revolutionized various domains, with biomedicine standing out as a major beneficiary. In the realm of biomedicine, Convolutional Neural Networks (CNNs) have notably played a pivotal role since their inception, particularly in applications such as time-series classification. Deep Convolutional Neural Networks (DCNNs) have shown promise in classifying electrocardiogram (ECG) signals. However, their deep architecture leads not only to risk for over-fitting when insufficient data is at hand, but also to large computational costs. This study leverages the efficient architecture of Mini-ROCKET, a variant of CNN, to explore improvements in ECG signal classification at Getinge. The primary objective is to enhance the efficiency of the Electrical Activity of the Diaphragm (Edi) catheter position classification compared to the existing Residual Network (ResNet) approach. In the Intensive Care Unit (ICU), patients are often connected to mechanical ventilators operating based on Edi catheter-detected signals. However, weak or absent EMG signals can occur, necessitating ECG interpretation, which lacks the precision required for optimal Edi catheter placement. Clinicians have long recognized the challenges of manual Edi catheter positioning. Currently, positioning relies on manual interpretation of electromyography (EMG) and ECG signals from a 9-lead electrode array. Given the risk for electrode displacement due to patient movements, continuous monitoring by skilled clinicians is essential. This thesis demonstrates the potential of Mini-ROCKET in addressing these challenges. By training the model on Getinge’s proprietary ECG patient dataset, the study aims to measure improvements in computational cost, accuracy, and user value as compared to previous work with Edicathere positioning at Getinge. The findings of this research hold significant implications for the future of ECG signal classification and the broader application of Mini-ROCKET in medical signal processing. / Maskininlärning har revolutionerat många områden, varav biomedicin som visat enorm utveckling. Inom biomedicin har konvolutionella neurala nätverk (CNNs) gjort stor positiv påverkan, särskilt inom tillämpningar som tidsserieklassificering. Djupa konvolutionella neurala nätverk (DCNNs) har visat lovande resultat inom elektrokardiogram (EKG) klassificering. Deras djupa arkitektur leder dock inte bara till risk för överanpassning med bägränsad data till handa, utan även till betydliga beräkningskostnader. Denna studie utnyttjar den effektiva arkitekturen av Mini-ROCKET, en variant av CNN, för att utforska förbättringar i EKG-signal klassificering på Getinge. Huvudmålet är att förbättra effektiviteten av Edi kateterpositionsklassificering jämfört med den befintliga Residual Network (ResNet) metoden. På intensivvårdsavdelningen (IVA) kopplas patienter ofta till mekaniska ventilatorer som fungerar baserat på Edi-kateter-detekterade signaler. Dock kan svaga eller frånvarande EMG-signaler förekomma, vilket kräver EKG-tolkning, som saknar den precision som krävs för optimal Edikateterplacering. Det är väl känt att det finns svårigheter för kliniker att positionera en matningssond utrustad med elektroder för att mäta Edi. För närvarande bygger positionering på manuell tolkning av elektromyografi (EMG) och EKG-signaler från en uppsättning av 9 elektroder. Med tanke på risken för elektrodförskjutning på grund av patientrörelser är kontinuerlig övervakning av erfarna användare nödvändigt. Denna avhandling visar potentialen av Mini-ROCKET för att ta itu med dessa utmaningar. Genom att träna modellen på Getinges proprietära EKGpatientdataset syftar studien till att mäta förbättringar i beräkningskostnad, noggrannhet och användarnytta jämfört med tidigare arbete inom Edi-kateter positionering på Getinge. Forskningens resultat har betydande implikationer för EKG-signal klassificeringens framtid och den bredare tillämpningen av Mini-ROCKET inom medicinsk signalbehandling.
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A Convolutional Neural Network for predicting HIV Integration SitesMatuh Delic, Senad January 2020 (has links)
Convolutional neural networks are commonly used when training deep networks with time-independent data and have demonstrated positive results in predicting DNA binding sites for DNA-binding proteins. Based upon the success of convolutional neural networks in predicting DNA binding sites of proteins, this project intends to determine if a convolutional neural network could predict possible HIV-B provirus integration sites. When exploring existing research, little information was found regarding DNA sequences targeted by HIV for integration, few, if any, have attempted to use artificial neural networks to identify these sequences and the integration sites themselves. Using data from the Retrovirus Integration Database, we train a convolutional artificial neural network to determine if it can detect potential target sites for HIV integration. The analysis and results reveal that the created convolutional neural network is able to predict HIV integration sites in human DNA with an accuracy that exceeds that of a potential random binary classifier. When analyzing the datasets separated by the neural network, the relative distribution of the different nucleotides in the immediate vicinity of HIV integration site reveals that some nucleotides are disproportionately occurring less often at these sites compared to nucleotides in randomly sampled human DNA. / Konvolutionella artificiella nätverk används vanligen vid tidsoberoende datamängder. Konvolutionella artificiella nätverk har varit framgångsrika med att förutse bindningssiter för DNA-bindande proteiner. Med de framsteg som gjorts med konvolutionella artificiella nätverk vill detta projekt bestämma huruvida det går att med ett konvolutionellt artificiella nätverk förutsäga möjliga siter för HIV-B integration i mänskligt DNA. Våran eftersökning visar att det finns lite kunskap om huruvida det finns nukleotidsekvenser i mänskligt DNA som främjar HIV integration. Samtidigt har få eller inga studier gjorts med konvolutionella artificiella nätverk i försök att förutsäga integrationssiter för HIV i mänskligt DNA. Genom att använda data från Retrovirus Integration Database tänker vi träna ett konvolutionellt artificiellt nätverk med syftet att försöka bestämma huruvida det tränade konvolutionella artificiella nätverket kan förutspå potentiella integrationssiter för HIV. Våra resultat visar att det skapade konvolutionella artificiella nätverket kan förutsäga HIV integration i mänskligt DNA med en träffsäkerhet som överträffar en potentiell slumpmässig binär klassificerare. Vid analys av datamängderna separerade av det neurala nätverket framträder en bild där vissa nukleotider förekommer oproportionerligt mindre frekvent i närheten av integrationssiterna i jämförelse med nukleotider i slumpmässigt genererad mänsklig DNA.
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[pt] DESENVOLVIMENTO DE PIV ULTRA PRECISO PARA BAIXOS GRADIENTES USANDO ABORDAGEM HÍBRIDA DE CORRELAÇÃO CRUZADA E CASCATA DE REDE NEURAIS CONVOLUCIONAIS / [en] DEVELOPMENT OF ULTRA PRECISE PIV FOR LOW GRADIENTS USING HYBRID CROSS-CORRELATION AND CASCADING NEURAL NETWORK CONVOLUTIONAL APPROACHCARLOS EDUARDO RODRIGUES CORREIA 31 January 2022 (has links)
[pt] Ao longo da história a engenharia de fluidos vem se mostrado como uma das áreas mais
importantes da engenharia devido ao seu impacto nas áreas de transporte, energia e militar. A
medição de campos de velocidade, por sua vez, é muito importante para estudos nas áreas de
aerodinâmica e hidrodinâmica. As técnicas de medição de campo de velocidade em sua maioria
são técnicas ópticas, se destacando a técnica de Particle Image Velocimetry (PIV). Por outro
lado, nos últimos anos importantes avanços na área de visão computacional, baseados em redes
neurais convolucionais, se mostram promissores para a melhoria do processamento das técnicas
ópticas. Nesta dissertação, foi utilizada uma abordagem híbrida entre correlação cruzada e
cascata de redes neurais convolucionais, para desenvolver uma nova técnica de PIV. O projeto
se baseou nos últimos trabalhos de PIV com redes neurais artificiais para desenvolver a
arquitetura das redes e sua forma de treinamento. Diversos formatos de cascata de redes neurais
foram testados até se chegar a um formato que permitiu reduzir o erro em uma ordem de
grandeza para escoamento uniforme. Além do desenvolvimento da cascata para escoamento
uniforme, gerou-se conhecimento para fazer cascatas para outros tipos de escoamentos. / [en] Throughout history, fluid engineering is one of the most important areas of engineering
due to its impact in the areas of transportation, energy and the military. The measurement of
velocity fields is important for studies in aerodynamics and hydrodynamics. The techniques for
measuring the velocity field are mostly optical techniques, with emphasis on the PIV technique.
On the other hand, in recent years, important advances in computer vision, based on
convolutional neural networks, have shown promise for improving the processing of optical
techniques. In this work, a hybrid approach between cross-correlation and cascade of
convolutional neural networks was used to develop a new PIV technique. The project was based
on the latest work of PIV with an artificial neural network to develop the architecture of the
networks and their form of training. Several cascade formats of neural networks were tested
until they reached a format that allowed the error to be reduced by an order of magnitude for
uniform flow. In addition to the development of the cascade for uniform flow, knowledge was
generated to make cascades for other types of flows.
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