249 research outputs found

    Representation and fusion of heterogeneous fuzzy information in the 3D space for model-based structural recognition—Application to 3D brain imaging

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    AbstractWe present a novel approach to model-based pattern recognition where structural information and spatial relationships have a most important role. It is illustrated in the domain of 3D brain structure recognition using an anatomical atlas. Our approach performs segmentation and recognition of the scene simultaneously. The solution of the recognition task is progressive, processing successively different objects, and using different pieces of knowledge about the object and about relationships between objects. Therefore, the core of the approach is the knowledge representation part, and constitutes the main contribution of this paper. We make use of a spatial representation of each piece of information, as a spatial fuzzy set representing a constraint to be satisfied by the searched object, thanks in particular to fuzzy mathematical morphology operations. Fusion of these constraints allows us to select, segment and recognize the desired object

    Image categorisation using parallel network constructs: an emulation of early human colour processing and context evaluation

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    PhD ThesisTraditional geometric scene analysis cannot attempt to address the understanding of human vision. Instead it adopts an algorithmic approach, concentrating on geometric model fitting. Human vision, however, is both quick and accurate but very little is known about how the recognition of objects is performed with such speed and efficiency. It is thought that there must be some process both for coding and storage which can account for these characteristics. In this thesis a more strict emulation of human vision, based on work derived from medical psychology and other fields, is proposed. Human beings must store perceptual information from which to make comparisons, derive structures and classify objects. It is widely thought by cognitive psychologists that some form of symbolic representation is inherent in this storage. Here a mathematical syntax is defined to perform this kind of symbolic description. The symbolic structures must be capable of manipulation and a set of operators is defined for this purpose. The early visual cortex and geniculate body are both inherently parallel in operation and simple in structure. A broadly connectionist emulation of this kind of structure is described, using independent computing elements, which can perform segmentation, re-colouring and generation of the base elements of the description syntax. Primal colour information is then collected by a second network which forms the visual topology, colouring and position information of areas in the image as well as a full description of the scene in terms of a more complex symbolic set. The idea of different visual contexts is introduced and a model is proposed for the accumulation of context rules. This model is then applied to a database of natural images.EPSRC CASE award: Neural Computer Sciences,Southampton

    Contributions of Continuous Max-Flow Theory to Medical Image Processing

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    Discrete graph cuts and continuous max-flow theory have created a paradigm shift in many areas of medical image processing. As previous methods limited themselves to analytically solvable optimization problems or guaranteed only local optimizability to increasingly complex and non-convex functionals, current methods based now rely on describing an optimization problem in a series of general yet simple functionals with a global, but non-analytic, solution algorithms. This has been increasingly spurred on by the availability of these general-purpose algorithms in an open-source context. Thus, graph-cuts and max-flow have changed every aspect of medical image processing from reconstruction to enhancement to segmentation and registration. To wax philosophical, continuous max-flow theory in particular has the potential to bring a high degree of mathematical elegance to the field, bridging the conceptual gap between the discrete and continuous domains in which we describe different imaging problems, properties and processes. In Chapter 1, we use the notion of infinitely dense and infinitely densely connected graphs to transfer between the discrete and continuous domains, which has a certain sense of mathematical pedantry to it, but the resulting variational energy equations have a sense of elegance and charm. As any application of the principle of duality, the variational equations have an enigmatic side that can only be decoded with time and patience. The goal of this thesis is to show the contributions of max-flow theory through image enhancement and segmentation, increasing incorporation of topological considerations and increasing the role played by user knowledge and interactivity. These methods will be rigorously grounded in calculus of variations, guaranteeing fuzzy optimality and providing multiple solution approaches to addressing each individual problem

    Topological Foundations of Cognitive Science

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    A collection of papers presented at the First International Summer Institute in Cognitive Science, University at Buffalo, July 1994, including the following papers: ** Topological Foundations of Cognitive Science, Barry Smith ** The Bounds of Axiomatisation, Graham White ** Rethinking Boundaries, Wojciech Zelaniec ** Sheaf Mereology and Space Cognition, Jean Petitot ** A Mereotopological Definition of 'Point', Carola Eschenbach ** Discreteness, Finiteness, and the Structure of Topological Spaces, Christopher Habel ** Mass Reference and the Geometry of Solids, Almerindo E. Ojeda ** Defining a 'Doughnut' Made Difficult, N .M. Gotts ** A Theory of Spatial Regions with Indeterminate Boundaries, A.G. Cohn and N.M. Gotts ** Mereotopological Construction of Time from Events, Fabio Pianesi and Achille C. Varzi ** Computational Mereology: A Study of Part-of Relations for Multi-media Indexing, Wlodek Zadrozny and Michelle Ki

    A Unified Cognitive Model of Visual Filling-In Based on an Emergic Network Architecture

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    The Emergic Cognitive Model (ECM) is a unified computational model of visual filling-in based on the Emergic Network architecture. The Emergic Network was designed to help realize systems undergoing continuous change. In this thesis, eight different filling-in phenomena are demonstrated under a regime of continuous eye movement (and under static eye conditions as well). ECM indirectly demonstrates the power of unification inherent with Emergic Networks when cognition is decomposed according to finer-grained functions supporting change. These can interact to raise additional emergent behaviours via cognitive re-use, hence the Emergic prefix throughout. Nevertheless, the model is robust and parameter free. Differential re-use occurs in the nature of model interaction with a particular testing paradigm. ECM has a novel decomposition due to the requirements of handling motion and of supporting unified modelling via finer functional grains. The breadth of phenomenal behaviour covered is largely to lend credence to our novel decomposition. The Emergic Network architecture is a hybrid between classical connectionism and classical computationalism that facilitates the construction of unified cognitive models. It helps cutting up of functionalism into finer-grains distributed over space (by harnessing massive recurrence) and over time (by harnessing continuous change), yet simplifies by using standard computer code to focus on the interaction of information flows. Thus while the structure of the network looks neurocentric, the dynamics are best understood in flowcentric terms. Surprisingly, dynamic system analysis (as usually understood) is not involved. An Emergic Network is engineered much like straightforward software or hardware systems that deal with continuously varying inputs. Ultimately, this thesis addresses the problem of reduction and induction over complex systems, and the Emergic Network architecture is merely a tool to assist in this epistemic endeavour. ECM is strictly a sensory model and apart from perception, yet it is informed by phenomenology. It addresses the attribution problem of how much of a phenomenon is best explained at a sensory level of analysis, rather than at a perceptual one. As the causal information flows are stable under eye movement, we hypothesize that they are the locus of consciousness, howsoever it is ultimately realized

    Attention-controlled acquisition of a qualitative scene model for mobile robots

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    Haasch A. Attention-controlled acquisition of a qualitative scene model for mobile robots. Bielefeld (Germany): Bielefeld University; 2007.Robots that are used to support humans in dangerous environments, e.g., in manufacture facilities, are established for decades. Now, a new generation of service robots is focus of current research and about to be introduced. These intelligent service robots are intended to support humans in everyday life. To achieve a most comfortable human-robot interaction with non-expert users it is, thus, imperative for the acceptance of such robots to provide interaction interfaces that we humans are accustomed to in comparison to human-human communication. Consequently, intuitive modalities like gestures or spontaneous speech are needed to teach the robot previously unknown objects and locations. Then, the robot can be entrusted with tasks like fetch-and-carry orders even without an extensive training of the user. In this context, this dissertation introduces the multimodal Object Attention System which offers a flexible integration of common interaction modalities in combination with state-of-the-art image and speech processing techniques from other research projects. To prove the feasibility of the approach the presented Object Attention System has successfully been integrated in different robotic hardware. In particular, the mobile robot BIRON and the anthropomorphic robot BARTHOC of the Applied Computer Science Group at Bielefeld University. Concluding, the aim of this work, to acquire a qualitative Scene Model by a modular component offering object attention mechanisms, has been successfully achieved as demonstrated on numerous occasions like reviews for the EU-integrated Project COGNIRON or demos

    Digital Image Access & Retrieval

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    The 33th Annual Clinic on Library Applications of Data Processing, held at the University of Illinois at Urbana-Champaign in March of 1996, addressed the theme of "Digital Image Access & Retrieval." The papers from this conference cover a wide range of topics concerning digital imaging technology for visual resource collections. Papers covered three general areas: (1) systems, planning, and implementation; (2) automatic and semi-automatic indexing; and (3) preservation with the bulk of the conference focusing on indexing and retrieval.published or submitted for publicatio

    A Framework For Abstracting, Designing And Building Tangible Gesture Interactive Systems

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    This thesis discusses tangible gesture interaction, a novel paradigm for interacting with computer that blends concepts from the more popular fields of tangible interaction and gesture interaction. Taking advantage of the human innate abilities to manipulate physical objects and to communicate through gestures, tangible gesture interaction is particularly interesting for interacting in smart environments, bringing the interaction with computer beyond the screen, back to the real world. Since tangible gesture interaction is a relatively new field of research, this thesis presents a conceptual framework that aims at supporting future work in this field. The Tangible Gesture Interaction Framework provides support on three levels. First, it helps reflecting from a theoretical point of view on the different types of tangible gestures that can be designed, physically, through a taxonomy based on three components (move, hold and touch) and additional attributes, and semantically, through a taxonomy of the semantic constructs that can be used to associate meaning to tangible gestures. Second, it helps conceiving new tangible gesture interactive systems and designing new interactions based on gestures with objects, through dedicated guidelines for tangible gesture definition and common practices for different application domains. Third, it helps building new tangible gesture interactive systems supporting the choice between four different technological approaches (embedded and embodied, wearable, environmental or hybrid) and providing general guidance for the different approaches. As an application of this framework, this thesis presents also seven tangible gesture interactive systems for three different application domains, i.e., interacting with the In-Vehicle Infotainment System (IVIS) of the car, the emotional and interpersonal communication, and the interaction in a smart home. For the first application domain, four different systems that use gestures on the steering wheel as interaction means with the IVIS have been designed, developed and evaluated. For the second application domain, an anthropomorphic lamp able to recognize gestures that humans typically perform for interpersonal communication has been conceived and developed. A second system, based on smart t-shirts, recognizes when two people hug and reward the gesture with an exchange of digital information. Finally, a smart watch for recognizing gestures performed with objects held in the hand in the context of the smart home has been investigated. The analysis of existing systems found in literature and of the system developed during this thesis shows that the framework has a good descriptive and evaluative power. The applications developed during this thesis show that the proposed framework has also a good generative power.Questa tesi discute l’interazione gestuale tangibile, un nuovo paradigma per interagire con il computer che unisce i principi dei più comuni campi di studio dell’interazione tangibile e dell’interazione gestuale. Sfruttando le abilità innate dell’uomo di manipolare oggetti fisici e di comunicare con i gesti, l’interazione gestuale tangibile si rivela particolarmente interessante per interagire negli ambienti intelligenti, riportando l’attenzione sul nostro mondo reale, al di là dello schermo dei computer o degli smartphone. Poiché l’interazione gestuale tangibile è un campo di studio relativamente recente, questa tesi presenta un framework (quadro teorico) che ha lo scopo di assistere lavori futuri in questo campo. Il Framework per l’Interazione Gestuale Tangibile fornisce supporto su tre livelli. Per prima cosa, aiuta a riflettere da un punto di vista teorico sui diversi tipi di gesti tangibili che possono essere eseguiti fisicamente, grazie a una tassonomia basata su tre componenti (muovere, tenere, toccare) e attributi addizionali, e che possono essere concepiti semanticamente, grazie a una tassonomia di tutti i costrutti semantici che permettono di associare dei significati ai gesti tangibili. In secondo luogo, il framework proposto aiuta a concepire nuovi sistemi interattivi basati su gesti tangibili e a ideare nuove interazioni basate su gesti con gli oggetti, attraverso linee guida per la definizione di gesti tangibili e una selezione delle migliore pratiche per i differenti campi di applicazione. Infine, il framework aiuta a implementare nuovi sistemi interattivi basati su gesti tangibili, permettendo di scegliere tra quattro differenti approcci tecnologici (incarnato e integrato negli oggetti, indossabile, distribuito nell’ambiente, o ibrido) e fornendo una guida generale per la scelta tra questi differenti approcci. Come applicazione di questo framework, questa tesi presenta anche sette sistemi interattivi basati su gesti tangibili, realizzati per tre differenti campi di applicazione: l’interazione con i sistemi di infotainment degli autoveicoli, la comunicazione interpersonale delle emozioni, e l’interazione nella casa intelligente. Per il primo campo di applicazione, sono stati progettati, sviluppati e testati quattro differenti sistemi che usano gesti tangibili effettuati sul volante come modalità di interazione con il sistema di infotainment. Per il secondo campo di applicazione, è stata concepita e sviluppata una lampada antropomorfica in grado di riconoscere i gesti tipici dell’interazione interpersonale. Per lo stesso campo di applicazione, un secondo sistema, basato su una maglietta intelligente, riconosce quando due persone si abbracciano e ricompensa questo gesto con uno scambio di informazioni digitali. Infine, per l’interazione nella casa intelligente, è stata investigata la realizzazione di uno smart watch per il riconoscimento di gesti eseguiti con oggetti tenuti nella mano. L’analisi dei sistemi interattivi esistenti basati su gesti tangibili permette di dimostrare che il framework ha un buon potere descrittivo e valutativo. Le applicazioni sviluppate durante la tesi mostrano che il framework proposto ha anche un valido potere generativo

    Towards automatic modeling of buildings in informal settlements from aerial photographs using deformable active contour models (snakes)

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    Bibliography: leaves 177-187.This dissertation presents a novel system for semi-automatic modeling of buildings in informal settlement areas from aerial photographs. The building extraction strategy is developed and implememed with the aim of generatinga a desk top Informal Settlement Geographic lnformation System (ISGIS) using felf developed and available PC-based GIS tools to serve novice users informal settlement areas
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