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1.
Sensors (Basel) ; 23(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37447876

RESUMO

The use of augmented reality (AR) technology is growing in the maintenance industry because it can improve efficiency and reduce costs by providing real-time guidance and instruction to workers during repairs and maintenance tasks. AR can also assist with equipment training and visualization, allowing users to explore the equipment's internal structure and size. The adoption of AR in maintenance is expected to increase as hardware options expand and development costs decrease. To implement AR for job aids in mobile applications, 3D spatial information and equipment details must be addressed, and calibrated using image-based or object-based tracking, which is essential for integrating 3D models with physical components. The present paper suggests a system using AR-assisted deep reinforcement learning (RL)-based model for NanoDrop Spectrophotometer training and maintenance purposes that can be used for rapid repair procedures in the Industry 4.0 (I4.0) setting. The system uses a camera to detect the target asset via feature matching, tracking techniques, and 3D modeling. Once the detection is completed, AR technologies generate clear and easily understandable instructions for the maintenance operator's device. According to the research findings, the model's target technique resulted in a mean reward of 1.000 and a standard deviation of 0.000. This means that all the rewards that were obtained in the given task or environment were exactly the same. The fact that the reward standard deviation is 0.000 shows that there is no variability in the outcomes.


Assuntos
Realidade Aumentada , Aplicativos Móveis , Cirurgia Assistida por Computador , Humanos , Cirurgia Assistida por Computador/métodos
2.
Ann Diagn Pathol ; 47: 151518, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32531442

RESUMO

Accurate detection and quantification of hepatic fibrosis remain essential for assessing the severity of non-alcoholic fatty liver disease (NAFLD) and its response to therapy in clinical practice and research studies. Our aim was to develop an integrated artificial intelligence-based automated tool to detect and quantify hepatic fibrosis and assess its architectural pattern in NAFLD liver biopsies. Digital images of the trichrome-stained slides of liver biopsies from patients with NAFLD and different severity of fibrosis were used. Two expert liver pathologists semi-quantitatively assessed the severity of fibrosis in these biopsies and using a web applet provided a total of 987 annotations of different fibrosis types for developing, training and testing supervised machine learning models to detect fibrosis. The collagen proportionate area (CPA) was measured and correlated with each of the pathologists semi-quantitative fibrosis scores. Models were created and tested to detect each of six potential fibrosis patterns. There was good to excellent correlation between CPA and the pathologist score of fibrosis stage. The coefficient of determination (R2) of automated CPA with the pathologist stages ranged from 0.60 to 0.86. There was considerable overlap in the calculated CPA across different fibrosis stages. For identification of fibrosis patterns, the models areas under the receiver operator curve were 78.6% for detection of periportal fibrosis, 83.3% for pericellular fibrosis, 86.4% for portal fibrosis and >90% for detection of normal fibrosis, bridging fibrosis, and presence of nodule/cirrhosis. In conclusion, an integrated automated tool could accurately quantify hepatic fibrosis and determine its architectural patterns in NAFLD liver biopsies.


Assuntos
Inteligência Artificial/estatística & dados numéricos , Colágeno/análise , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Automação/métodos , Compostos Azo/metabolismo , Biópsia , Ensaios Clínicos como Assunto , Colágeno/metabolismo , Amarelo de Eosina-(YS)/metabolismo , Fibrose/classificação , Fibrose/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Fígado/patologia , Verde de Metila/metabolismo , Escores de Disfunção Orgânica , Patologistas/estatística & dados numéricos , Veia Porta/fisiopatologia , Padrões de Prática Médica/normas , Índice de Gravidade de Doença , Aprendizado de Máquina Supervisionado/estatística & dados numéricos
3.
PLoS One ; 13(5): e0197242, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29746543

RESUMO

Although mice are commonly used to study different aspects of fatty liver disease, currently there are no validated fully automated methods to assess steatosis in mice. Accurate detection of macro- and microsteatosis in murine models of fatty liver disease is important in studying disease pathogenesis and detecting potential hepatotoxic signature during drug development. Further, precise quantification of macrosteatosis is essential for quantifying effects of therapies. Here, we develop and validate the performance of automated classifiers built using image processing and machine learning methods for detection of macro- and microsteatosis in murine fatty liver disease and study the correlation of automated quantification of macrosteatosis with expert pathologist's semi-quantitative grades. The analysis is performed on digital images of 27 Hematoxylin & Eosin stained murine liver biopsy samples. An expert liver pathologist scored the amount of macrosteatosis and also annotated macro- and microsteatosis lesions on the biopsy images using a web-application. Using these annotations, supervised machine learning and image processing techniques, we created classifiers to detect macro- and microsteatosis. For macrosteatosis prediction, the model's precision, sensitivity and area under the receiver operator characteristic (AUROC) were 94.2%, 95%, 99.1% respectively. When correlated with pathologist's semi-quantitative grade of steatosis, the model fits with a coefficient of determination value of 0.905. For microsteatosis prediction, the model has precision, sensitivity and AUROC of 79.2%, 77%, 78.1% respectively. Validation by the expert pathologist of classifier's predictions made on unseen images of biopsy samples showed 100% and 63% accuracy for macro- and microsteatosis, respectively. This novel work demonstrates that fully automated assessment of steatosis is feasible in murine liver biopsies images. Our classifier has excellent sensitivity and accuracy for detection of macrosteatosis in murine fatty liver disease.


Assuntos
Automação Laboratorial/métodos , Fígado Gorduroso/patologia , Interpretação de Imagem Assistida por Computador/métodos , Fígado/patologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Reconhecimento Automatizado de Padrão/métodos , Aprendizado de Máquina Supervisionado
4.
J Forensic Sci ; 63(6): 1652-1660, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29684936

RESUMO

This study using three-dimensional cone beam computed tomography (CBCT) images of children determined relationships between nasal skeletal and soft tissue measurements and assessed the association with sex, age, and skeletal maturation stage. Following reliability studies, skeletal and soft tissue parameters were measured on coded CBCTs of 73 children (28M:45F;6-13 yoa). Pearson and Mantel correlations were used to analyze associations between skeletal and soft tissues. Partial Mantel correlations were used to study the associations between skeletal and soft tissue, adjusting for sex, age, and skeletal maturation. Linear regression analyses were used to predict soft tissues sizes. Logistic regression was used to study the relationships between soft and skeletal tissue symmetry. Except for nasal aperture width and interalar width, skeletal landmarks best predicted corresponding soft tissue landmarks. Significant positive associations existed between skeletal and soft tissues after adjusting for sex, skeletal maturation, and age. Children's nasal skeletal tissues predicted nasal soft tissue reasonably well.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Nariz/anatomia & histologia , Nariz/diagnóstico por imagem , Adolescente , Pontos de Referência Anatômicos , Criança , Feminino , Antropologia Forense , Humanos , Modelos Lineares , Masculino
5.
J Forensic Sci ; 56 Suppl 1: S83-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20887354

RESUMO

In forensic dentistry, a human expert typically does the comparison and identification based on bite marks. Unlike DNA analysis, however, there is no quantitative basis with which to assign a probability for this given match. This paper proposes a framework for empirically estimating the probability of such a bite mark match and reports on initial experimental results. The methodology involved collection of dental population data (3D dental casts and bite mark images), image analysis for quantitatively measuring the degree of match (based on chamfer distance), and performing a logistic regression analysis using the collected population data to estimate the probability of match from the calculated degree of match. The model correctly predicted 35 of the 42 matches and 585 of the 588 mismatches. The method also has potential for use in other forensic applications in which the assignment of quantitative probabilities is important.


Assuntos
Mordeduras Humanas/patologia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Modelos Dentários , Probabilidade , Odontologia Legal/métodos , Humanos , Análise de Regressão
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