Tissue segmentation using medical image processing chain optimization

Surveyed literature shows many segmentation algorithms using different types of optimization methods. These methods were used to minimize or maximize objective functions of entropy, similarity, clustering, contour, or thresholding. These specially developed functions target specific feature or step in the presented segmentation algorithms. To the best of our knowledge, this thesis is the first research work that uses an optimizer to build and optimize parameters of a full sequence of image processing chain. This thesis presents a universal algorithm that uses three images and their corresponding gold images to train the framework. The optimization algorithm explores the search space for the best sequence of the image processing chain to segment the targeted feature. Experiments indicate that using differential evolution to build Image processing chain (IPC) out of forty-five algorithms increases the segmentation performance of basic thresholding algorithms ranging from 2% to 78%

Design of a Real-Time Method for Detection and Evaluation of Corrosion in Vehicles

Automobiles endure several challenges when operating on the road that can degrade their performance, functionality, appearance, and overall utility. Although, corrosion is very ancient, it is the most dangerous hazard to an automobile. Corrosion can be defined as natural interaction between the metal and its surrounding atmosphere which results in oxidation of metal. This leads to change in metal properties and can be severely dangerous. One of the easiest ways to recognize corrosion is by using visual inspection methods. Visual inspection results are highly dependent on the operator’s way of analyzing corrosion and operator’s experience. Thus, visual inspection method lack standardization and is susceptible to human errors. In this research, an automated digital method is proposed to detect the surface corrosion and estimate the damage caused. The new approach has been designed to work effectively irrespective of the illumination levels, image dis-orientation and variance in rust texture. The proposed method in proven to be 96% accurate. Furthermore, the proposed method is designed in the form of a noncommercial, cloud-oriented app which is efficient, fast, low-cost, low-maintenance and possesses global accessibility

Endoscopic image analysis of aberrant crypt foci

Tese de Mestrado Integrado. Bioengenharia. Faculdade de Engenharia. Universidade do Porto. 201

Experimental investigation of microstructure and properties in structural alloys through image analyses and multiresolution indentation

This work addresses the challenges in the investigation of structural alloy microstructures and their mechanical properties at multiple length scales. The investigations are performed on small volume ferrite-pearlite steel samples that were excised from in-service gas turbine components after prolonged exposure (up to 99,000 hours) to elevated temperatures, which promotes microstructural changes (spheroidization of pearlite and graphitization) as well as their yield strengths. Recent advances in spherical indentation protocols are combined for the first time to investigate the mechanical response of microscale ferrite-pearlite constituents and estimates of bulk properties on macroscale. It is shown that indentation yield strength captured with large indenter tips on an ensemble of ferrite-pearlite grains correlate strongly to the bulk yield strength evaluated with tensile measurements. Measurements on the individual ferrite and pearlite constituents follow a similar trend of decreasing yield strength as the bulk measurements. Second, to advance the reliability and accuracy of microstructure characterization, an image segmentation framework is developed that consists of five main steps designed to achieve systematic image segmentation on broad classes of microstructures utilizing widely available image processing tools. The flexibility and modularity of the framework was demonstrated on various types of microstructures images. The developed framework was used to segment the microstructures of ferrite-pearlite samples. The extracted microstructure statistics from the segmented images and multiresolution indentation yield strength measurements were used to evaluate established composite theory estimates and have demonstrated highly consistent estimates for these material systems.Ph.D

Quantifying Glial-Glial Interactions In Drosophila Using Automated Image Analysis

Imaging is an immensely powerful tool in biomedical research. Technological advances in the last half century have led to the development of new tools for image analysis, with major strides being made in the last 20 years especially with machine and deep learning. However, researchers still often hit a bottleneck during the image analysis phase of their projects that often leads to delays and sometimes even limits the scope of their studies. In this thesis I demonstrate some of the issues that arise while quantifying images to answer a biological question by using a dataset of fly central nervous system images to elucidate interactions between different cells. I present an overview of the types of methods that can be used to perform this analysis including a discussion of their advantages and disadvantages. Finally, I present steps for creating and validating an automated image analysis pipeline that was used to analyze a large section of the fly ventral nerve cord, akin to the spinal cord. Automating image quantifying allowed us to maximize the size of the dataset analyzed, which revealed subtle patterns in cell-cell interactions that would not have been uncovered with manual quantification of a smaller dataset

Character Recognition

Character recognition is one of the pattern recognition technologies that are most widely used in practical applications. This book presents recent advances that are relevant to character recognition, from technical topics such as image processing, feature extraction or classification, to new applications including human-computer interfaces. The goal of this book is to provide a reference source for academic research and for professionals working in the character recognition field