4,914 research outputs found

    Hyperspectral Tomographic FTIR Imaging Using Two Illumination Geometries for Polymer Phantoms

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    The purpose of this dissertation is to carry out non-destructive 3D imaging by applying Fourier Transform Infrared (FTIR) spectro-microtomographic techniques, and develop corresponding methods of data analysis. This is done by collecting 3D synchrotron-based and lab-based (Thermal) FTIR hyper spectral data at the Synchrotron Radiation Center (SRC) for the first time. Despite other 2D imaging techniques, this does not manipulate the sample, and suppresses the need to microtome 3D biological, material or biomedical samples into slices to study by spectroscopic imaging techniques. Spectro-micro-tomography is applicable for scientific, industrial, energy, biomedical samples such as stem cell characterization and materials such as polymers. Tomographic reconstruction methods are employed to the data to investigate the chemical and morphological localization, and obtain the average spectra of regions of interest as well as spectra for every voxel. It is assumed that the thermal light has cone geometry, and the data collected needs cone beam reconstruction, whereas the data collected using synchrotron light requires parallel beam reconstruction, since the beam waist created by the focus at IR wavelengths of the synchrotron 12 beams can be approximated well by a parallel beam. While bright synchrotron light provides us with higher SNR data, the capability of doing FTIR spectro-micro-tomographic techniques using thermal light, processing and analyzing it is of a high significance since thermal sources are more readily available. In this study the cone beam reconstruction is implemented and evaluated by applying them to the phantoms such as centered and off-center Polystyrene beads, and samples of mixed-polymers. The results of the cone beam reconstruction show that the cone beam reconstruction does not improve the quality of the reconstruction, and the parallel beam reconstruction is still better. The cone beam is not capable of modelling the optical system of our imaging environment, and the half cone beam angle size is small enough to be considered as parallel beam. Furthermore, the application of the cone beam is limited to the size of the sample. For further analysis of the 3D reconstructed volumes of the samples, specific signal processing tools are required. The deconvolution algorithm is applied to the 2D projections at all the wavelengths before the reconstruction to increase the image contrast and spectral fidelity, deblur the projections, and finally increase the contrast of the 3D images. Segmentation methods will be implemented for defining the regions of interest in the 3D structures; this will be used for average spectrum computation as a necessary tool of spectral analysis. The techniques developed here employ thresholding and kmeans clustering are capable of calculating the average spectra of the components found in the data as well as their corresponding renderings

    Atlas Toolkit: Fast registration of 3D morphological datasets in the absence of landmarks

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    Image registration is a gateway technology for Developmental Systems Biology, enabling computational analysis of related datasets within a shared coordinate system. Many registration tools rely on landmarks to ensure that datasets are correctly aligned; yet suitable landmarks are not present in many datasets. Atlas Toolkit is a Fiji/ImageJ plugin collection offering elastic group-wise registration of 3D morphological datasets, guided by segmentation of the interesting morphology. We demonstrate the method by combinatorial mapping of cell signalling events in the developing eyes of chick embryos, and use the integrated datasets to predictively enumerate Gene Regulatory Network states

    Satellite on-board processing for earth resources data

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    Results of a survey of earth resources user applications and their data requirements, earth resources multispectral scanner sensor technology, and preprocessing algorithms for correcting the sensor outputs and for data bulk reduction are presented along with a candidate data format. Computational requirements required to implement the data analysis algorithms are included along with a review of computer architectures and organizations. Computer architectures capable of handling the algorithm computational requirements are suggested and the environmental effects of an on-board processor discussed. By relating performance parameters to the system requirements of each of the user requirements the feasibility of on-board processing is determined for each user. A tradeoff analysis is performed to determine the sensitivity of results to each of the system parameters. Significant results and conclusions are discussed, and recommendations are presented

    Proceedings of Abstracts Engineering and Computer Science Research Conference 2019

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    © 2019 The Author(s). This is an open-access work distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. For further details please see https://creativecommons.org/licenses/by/4.0/. Note: Keynote: Fluorescence visualisation to evaluate effectiveness of personal protective equipment for infection control is © 2019 Crown copyright and so is licensed under the Open Government Licence v3.0. Under this licence users are permitted to copy, publish, distribute and transmit the Information; adapt the Information; exploit the Information commercially and non-commercially for example, by combining it with other Information, or by including it in your own product or application. Where you do any of the above you must acknowledge the source of the Information in your product or application by including or linking to any attribution statement specified by the Information Provider(s) and, where possible, provide a link to this licence: http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/This book is the record of abstracts submitted and accepted for presentation at the Inaugural Engineering and Computer Science Research Conference held 17th April 2019 at the University of Hertfordshire, Hatfield, UK. This conference is a local event aiming at bringing together the research students, staff and eminent external guests to celebrate Engineering and Computer Science Research at the University of Hertfordshire. The ECS Research Conference aims to showcase the broad landscape of research taking place in the School of Engineering and Computer Science. The 2019 conference was articulated around three topical cross-disciplinary themes: Make and Preserve the Future; Connect the People and Cities; and Protect and Care

    Similarity Measures and Dimensionality Reduction Techniques for Time Series Data Mining

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    The chapter is organized as follows. Section 2 will introduce the similarity matching problem on time series. We will note the importance of the use of efficient data structures to perform search, and the choice of an adequate distance measure. Section 3 will show some of the most used distance measure for time series data mining. Section 4 will review the above mentioned dimensionality reduction techniques
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