Advanced Image Acquisition, Processing Techniques and Applications

"Advanced Image Acquisition, Processing Techniques and Applications" is the first book of a series that provides image processing principles and practical software implementation on a broad range of applications. The book integrates material from leading researchers on Applied Digital Image Acquisition and Processing. An important feature of the book is its emphasis on software tools and scientific computing in order to enhance results and arrive at problem solution

ON THE LOGIC, METHOD AND SCIENTIFIC DIVERSITY OF TECHNICAL SYSTEMS: AN INQUIRY INTO THE DIAGNOSTIC MEASUREMENT OF HUMAN SKIN

This dissertation explores some of the scientific, technical and cultural history of human skin measurement and diagnostics. Through a significant collection of primary texts and case studies, I track the changing technologies and methods used to measure skin, as well as the scientific and sociotechnical applications. I then map these histories onto some of the diverse understandings of the human body, physics, biology, natural philosophy and language that underpinned the scientific enterprise of skin measurement. The main argument of my thesis demonstrates how these diverse histories of science historically and theoretically inform the succeeding methods and applications for skin measurement from early Greek medicine, to beginnings of Anthropology as scientific discipline, to the emergence of scientific racism, to the age of digital imaging analysis, remote sensing, algorithms, massive databases and biometric technologies; further, these new digital applications go beyond just health diagnostics and are creating new technical categorizations of human skin divorced from the established ethical mechanisms of modern science. Based on this research, I inquire how communication practices within the scientific enterprise address the ethical and historical implications for a growing set of digital biometric applications with industrial, military, sociopolitical and public functions

3D object reconstruction using computer vision : reconstruction and characterization applications for external human anatomical structures

Tese de doutoramento. Engenharia Informática. Faculdade de Engenharia. Universidade do Porto. 201

Change blindness: eradication of gestalt strategies

Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval before being 'overwritten' by the second presentation (Landman et al, 2003 Vision Research 43149–164]. Another possibility is that participants used some kind of grouping or Gestalt strategy. To test this we changed the spatial position of the rectangles in the second presentation by shifting them along imaginary spokes (by ±1 degree) emanating from the central fixation point. There was no significant difference seen in performance between this and the standard task [F(1,4)=2.565, p=0.185]. This may suggest two things: (i) Gestalt grouping is not used as a strategy in these tasks, and (ii) it gives further weight to the argument that objects may be stored and retrieved from a pre-attentional store during this task

Synergizing human-machine intelligence: Visualizing, labeling, and mining the electronic health record

We live in a world where data surround us in every aspect of our lives. The key challenge for humans and machines is how we can make better use of such data. Imagine what would happen if you were to have intelligent machines that could give you insight into the data. Insight that will enable you to better 1) reason about, 2) learn, and 3) understand the underlying phenomena that produced the data. The possibilities of combined human-machine intelligence are endless and will impact our lives in ways we can not even imagine today. Synergistic human-machine intelligence aims to facilitate the analytical reasoning and inference process of humans by creating machines that maximize a human's ability to 1) reason about, 2) learn, and 3) understand large, complex, and heterogeneous data. Combined human-machine intelligence is a powerful symbiosis of mutual benefit, in which we depend on the computational capabilities of the machine for the tasks we are not good at, and the machine requires human intervention for the tasks it performs poorly on. This relationship provides a compelling alternative to either approach in isolation for solving today's and tomorrow's arising data challenges. In his regard, this dissertation proposes a diverse analytical framework that leverages synergistic human-machine intelligence to maximize a human's ability to better 1) reason about, 2) learn, and 3) understand different biomedical imaging and healthcare data present in the patient's electronic health record (EHR). Correspondingly, we approach the data analyses problem from the 1) visualization, 2) labeling, and 3) mining perspective and demonstrate the efficacy of our analytics on specific application scenarios and various data domains. In the first part of this dissertation we explore the question how we can build intelligent imaging analytics that are commensurate with human capabilities and constraints, specifically for optimizing data visualization and automated labeling workflows. Our journey starts with heuristic rule-based analytical models that are derived from task-specific human knowledge. From this experience, we move on to data-driven analytics, where we adapt and combine the intelligence of the model based on prior information provided by the human and synthetic knowledge learned from partial data observations. Within this realm, we propose a novel Bayesian transductive Markov random field model that requires minimal human intervention and is able to cope with scarce label information to learn and infer object shapes in complex spatial, multimodal, spatio-temporal, and longitudinal data. We then study the question how machines can learn discriminative object representations from dense human provided label information by investigating learning and inference mechanisms that make use of deep learning architectures. The developed analytics can aid visualization and labeling tasks, which enables the interpretation and quantification of clinically relevant image information. The second part explores the question how we can build data-driven analytics for exploratory analysis in longitudinal event data that are commensurate with human capabilities and constraints. We propose human-intuitive analytics that enable the representation and discovery of interpretable event patterns to ease knowledge absorption and comprehension of the employed analytics model and the underlying data. We propose a novel doubly-constrained convolutional sparse-coding framework that learns interpretable and shift-invariant latent temporal event patterns. We apply the model to mine complex event data in EHRs. By mapping the event space to heterogeneous patient encounters in the EHR we explore the linkage between healthcare resource utilization (HRU) in relation to disease severity. This linkage may help to better understand how disease specific co-morbidities and their clinical attributes incur different HRU patterns. Such insight helps to characterize the patient's care history, which then enables the comparison against clinical practice guidelines, the discovery of prevailing practices based on common HRU group patterns, and the identification of outliers that might indicate poor patient management

Aerospace medicine and biology: A cumulative index to the continuing bibliography of the 1973 issues

A cumulative index to the abstracts contained in Supplements 112 through 123 of Aerospace Medicine and Biology A Continuing Bibliography is presented. It includes three indexes: subject, personal author, and corporate source

Neuronal representation of sound source location in the auditory cortex during active navigation

The ability to localize sounds is crucial for the survival of both predators as well as prey. The former rely on their senses to lead them to the latter, which in turn also benefit from locating a predator in the vicinity to escape accordingly. In such cases, the sound localization process typically takes place while the animals are in motion. Since the cues that the brain uses to localize sounds are head-centered (egocentric), they can change very rapidly when an animal moves and rotates. This constitutes an even bigger challenge than sound localization in a static environment. Up to now, however, both aspects have mostly been studied separately in neuroscience, thus limiting our understanding of active sound localization during navigation. This thesis reports on the development of a novel behavioral paradigm – the Sensory Island Task (SIT) – to promote sound localization during unrestricted motion. By attributing a different behavioral meaning (associated to different outcomes) to two spatially separated sound sources, Mongolian gerbils (Meriones unguiculatus) were trained to forage for an area (target island) in the arena that triggered a change in the active sound source to the target loudspeaker and to report its detection by remaining within the island for a duration of 6 s. Importantly, the two loudspeakers played identical sounds and the location of the target island in the arena was changed randomly every trial. When the probability of successfully identifying the target island exceeded the chance level, a tetrode bundle was implanted in the primary auditory cortex of the gerbils to record neuronal responses during task performance. Canonically, the auditory cortex (AC) is described as possessing neurons with a broad hemispheric tuning. Nonetheless, context and behavioral state have been shown to modulate the neuronal responses in the AC. The experiments described in this thesis demonstrate the existence of a large variety of additional, previously unreported (or underreported) spatial tuning types. In particular, neurons that were sensitive to the midline and, most intriguingly, neurons that were sensitive to the task identity of the active loudspeaker were observed. The latter comprise neurons that were spatially tuned to only one of the two loudspeakers, neurons that exhibited a large difference in the preferred egocentric sound-source location for the two loudspeakers as well as spatially untuned neurons whose firing rate changed depending on the active loudspeaker. Additionally, temporal complexity in the neuronal responses was observed, with neurons changing their preferred egocentric sound-source location throughout their response to a sound. Corroborating earlier studies, also here it was found that the task-specific choice of the animal was reflected in the neuronal responses. Specifically, the neuronal firing rate decreased before the animal successfully finished a trial in comparison to situations in which the gerbil incorrectly left the target island before trial completion. Furthermore, the differential behavioral meaning between the two loudspeakers was found to be represented in the neuronal tuning acuity, with neurons being more sharply tuned to sounds coming from the target than from the background loudspeaker. Lastly, by implementing an artificial neural network, all of the observed phenomena could be studied in a common framework, enabling a better and more comprehensive understanding of the computational relevance of the diversity of observed neuronal responses. Strikingly, the algorithm was capable of predicting not only the egocentric sound-source location but also which sound source was active – both with high accuracy. Taken together, the results presented in this thesis suggest the existence of an interlaced coding of egocentric and allocentric information in the neurons of the primary auditory cortex. These novel findings thus contribute towards a better understanding of how sound sources are perceptually stable during self-motion, an effect that could be advantageous for selective hearing

Advances in Image Processing, Analysis and Recognition Technology

For many decades, researchers have been trying to make computers’ analysis of images as effective as the system of human vision is. For this purpose, many algorithms and systems have previously been created. The whole process covers various stages, including image processing, representation and recognition. The results of this work can be applied to many computer-assisted areas of everyday life. They improve particular activities and provide handy tools, which are sometimes only for entertainment, but quite often, they significantly increase our safety. In fact, the practical implementation of image processing algorithms is particularly wide. Moreover, the rapid growth of computational complexity and computer efficiency has allowed for the development of more sophisticated and effective algorithms and tools. Although significant progress has been made so far, many issues still remain, resulting in the need for the development of novel approaches

Digital Morphometry : A Taxonomy Of Morphological Filters And Feature Parameters With Application To Alzheimer\u27s Disease Research

In this thesis the expression digital morphometry collectively describes all those procedures used to obtain quantitative measurements of objects within a two-dimensional digital image. Quantitative measurement is a two-step process: the application of geometrical transformations to extract the features of interest, and then the actual measurement of these features. With regard to the first step the morphological filters of mathematical morphology provide a wealth of suitable geometric transfomations. Traditional radiometric and spatial enhancement techniques provide an additional source of transformations. The second step is more classical (e.g. Underwood, 1970; Bookstein, 1978; and Weibull, 1980); yet here again mathematical morphology is applicable - morphologically derived feature parameters. This thesis focuses on mathematical morphology for digital morphometry. In particular it proffers a taxonomy of morphological filters and investigates the morphologically derived feature parameters (Minkowski functionals) for digital images sampled on a square grid. As originally conceived by Georges Matheron, mathematical morphology concerns the analysis of binary images by means of probing with structuring elements [typically convex geometric shapes] (Dougherty, 1993, preface). Since its inception the theory has been extended to grey-level images and most recently to complete lattices. It is within the very general framework of the complete lattice that the taxonomy of morphological filters is presented. Examples are provided to help illustrate the behaviour of each type of filter. This thesis also introduces DIMPAL (Mehnert, 1994) - a PC-based image processing and analysis language suitable for researching and developing algorithms for a wide range of image processing applications. Though DIMPAL was used to produce the majority of the images in this thesis it was principally written to provide an environment in which to investigate the application of mathematical morphology to Alzheimer\u27s disease research. Alzheimer\u27s disease is a form of progressive dementia associated with the degeneration of the brain. It is the commonest type of dementia and probably accounts for half the dementia of old age (Forsythe, 1990, p. 21 ). Post mortem examination of the brain reveals the presence of characteristic neuropathologic lesions; namely neuritic plaques and neurofibrillary tangles. They occur predominantly in the cerebral cortex and hippocampus. Quantitative studies of the distribution of plaques and tangles in normally aged and Alzheimer brains are hampered by the enormous amount of time and effort required to count and measure these lesions. Here in a morphological algorithm is proposed for the automatic segmentation and measurement of neuritic plaques from light micrographs of post mortem brain tissue

A cumulative index to the 1977 issues of a continuing bibliography on aerospace medicine and biology

This publication is a cumulative index to the abstracts contained in the Supplements 164 through 175 of Aerospace Medicine and Biology: A Continuing Bibliography. It includes three indexes-- subject, personal author, and corporate source