Anand Rangarajan | University of Florida (original) (raw)
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Papers by Anand Rangarajan
Journal of Imaging
Travel-time estimation of traffic flow is an important problem with critical implications for tra... more Travel-time estimation of traffic flow is an important problem with critical implications for traffic congestion analysis. We developed techniques for using intersection videos to identify vehicle trajectories across multiple cameras and analyze corridor travel time. Our approach consists of (1) multi-object single-camera tracking, (2) vehicle re-identification among different cameras, (3) multi-object multi-camera tracking, and (4) travel-time estimation. We evaluated the proposed framework on real intersections in Florida with pan and fisheye cameras. The experimental results demonstrate the viability and effectiveness of our method.
IEEE transactions on image processing, Feb 1, 2010
Abstract For the familiar 2-class detection problem (signal present/absent), ideal observers have... more Abstract For the familiar 2-class detection problem (signal present/absent), ideal observers have been applied to optimization of pinhole and collimator parameters in planar emission imaging. Given photon noise and background and signal variability, such experiments ...
American Mathematical Society eBooks, Dec 12, 2000
ABSTRACT
2006 IEEE Nuclear Science Symposium Conference Record, 2006
Proceedings of SPIE, Oct 10, 1994
ABSTRACT
Proceedings of SPIE, Jul 1, 1990
Proceedings of SPIE, Jul 29, 1993
International Conference on Pattern Recognition, Dec 1, 2008
IEEE Transactions on Medical Imaging, 2003
Neural Computation, Aug 1, 1999
2001 IEEE Nuclear Science Symposium Conference Record (Cat. No.01CH37310), Aug 25, 2005
We present a convex, edge-preserving prior, which we term a median prior, for regularized (or Bay... more We present a convex, edge-preserving prior, which we term a median prior, for regularized (or Bayesian) tomographic reconstruction. With its associated iterative algorithm, the prior can be described approximately as follows: at each iteration k, each object point fˆjk is attracted to the median formed from a local neighborhood surrounding fˆjk, while still trying to satisfy data consistency. With this
Computer Aided Surgery, 1999
arXiv (Cornell University), Jun 24, 2021
Journal of Imaging
Travel-time estimation of traffic flow is an important problem with critical implications for tra... more Travel-time estimation of traffic flow is an important problem with critical implications for traffic congestion analysis. We developed techniques for using intersection videos to identify vehicle trajectories across multiple cameras and analyze corridor travel time. Our approach consists of (1) multi-object single-camera tracking, (2) vehicle re-identification among different cameras, (3) multi-object multi-camera tracking, and (4) travel-time estimation. We evaluated the proposed framework on real intersections in Florida with pan and fisheye cameras. The experimental results demonstrate the viability and effectiveness of our method.
IEEE transactions on image processing, Feb 1, 2010
Abstract For the familiar 2-class detection problem (signal present/absent), ideal observers have... more Abstract For the familiar 2-class detection problem (signal present/absent), ideal observers have been applied to optimization of pinhole and collimator parameters in planar emission imaging. Given photon noise and background and signal variability, such experiments ...
American Mathematical Society eBooks, Dec 12, 2000
ABSTRACT
2006 IEEE Nuclear Science Symposium Conference Record, 2006
Proceedings of SPIE, Oct 10, 1994
ABSTRACT
Proceedings of SPIE, Jul 1, 1990
Proceedings of SPIE, Jul 29, 1993
International Conference on Pattern Recognition, Dec 1, 2008
IEEE Transactions on Medical Imaging, 2003
Neural Computation, Aug 1, 1999
2001 IEEE Nuclear Science Symposium Conference Record (Cat. No.01CH37310), Aug 25, 2005
We present a convex, edge-preserving prior, which we term a median prior, for regularized (or Bay... more We present a convex, edge-preserving prior, which we term a median prior, for regularized (or Bayesian) tomographic reconstruction. With its associated iterative algorithm, the prior can be described approximately as follows: at each iteration k, each object point fˆjk is attracted to the median formed from a local neighborhood surrounding fˆjk, while still trying to satisfy data consistency. With this
Computer Aided Surgery, 1999
arXiv (Cornell University), Jun 24, 2021
Russellian monism (RM) has emerged as a leading contender for a solution to the mind-body problem... more Russellian monism (RM) has emerged as a leading contender for a solution to the mind-body problem. Since we cannot expect deep familiarity with it, we briefly summarize the essentials before turning to our model of RM. RM basically agrees with dualism that qualia cannot be easily derived from the physical. At the same time, RM sides with physicalism which denies that qualia are fundamental and not grounded in anything. How can RM hold both perspectives at the same time? The answer is that RM posits a deeper and more fundamental reality from which both the conventional physical and qualia emerge. Consequently, in RM we do not assume that fundamental particles are the ground of the physical and phenomenal, thereby opening a space for grounding qualia in a deeper physical. Given this starting point, the rest is entirely straightforward: we use category theory (a leading mathematical framework) to model the mappings from new foundations to both the conventional physical and qualia. Since we cannot expect a background in category theory, we briefly summarize its essentials. Category theory is a framework for modeling compositional aspects of systems. Given a basic category (comprising objects and morphisms or transformations between pairs of objects), the mapping from one category to another is accomplished via functors (mappings which take objects in one category to objects in another category). Since this may appear to be very abstract, consider the illuminating example from quantum field theory: the mapping from quantum fields to particles - a.k.a. second quantization - is a functor. Therefore, even in present day physics, we can conceive of category theory driven mappings at work and raising foundational questions as to the origin of fundamental particles. Given the above, it is natural to ask if RM can be formulated using category theory and if so, what does this entail for both the physical and the phenomenal. We believe the answer lies in a middle-out as opposed to either top-down or bottom-up implementations. We can begin from a foundational category which is presently unknown and first create functors to the category of fundamental particles (like fermions and bosons) AND fields. This should not be too controversial since the ontology of quantum fields is far from settled at present. At the same time, we can construct a second functor from the foundational to the category of phenomenal objects which we call ``selfons'' in homage to fermions and bosons (which are seen as also emerging from this new foundation). Qualia in this framework are properties of selfons and grounded in the selfon category. We now circle back to our original RM-based intuition which eschews both dualism and present-day physicalism. Since selfons are derived from a second functor, this model asserts that qualia cannot be grounded in the physical (if that is taken to mean the category of fundamental particles). But, qualia are not foundational either since selfons are derived from a new RM-based foundational category. Thereby, we obtain a middle-out model of Russellian monism accommodating both the physical and the phenomenal.
The Science of Consciousness, Taormina, Sicily, 2023
We begin with the premise that Strawson's thin subject and Zahavi's minimal self are indispensabl... more We begin with the premise that Strawson's thin subject and Zahavi's minimal self are indispensable concepts in consciousness studies. While these concepts eschew naive Cartesianism, they affirm something basic in our phenomenology, that experience is always accompanied by a subject or perspective and this needs to be acknowledged in some form. We also note that there is a widespread belief that Buddhist studies affirm the concept of no-self which at first glance seems to be at odds with the thin subject and/or minimal self. The goal of this paper is to show that there is a Tibetan Buddhist tradition which affirms the thin subject (and/or minimal self) and this fact should be more widely disseminated in consciousness studies. A brief description of Tibetan Mahamudra follows: there are four yogas/stages in the Mahamudra tradition. In the first emptiness of self yoga, the practitioner is encouraged to discover that their prior (Cartesian) assumption of a fixed self is mistaken and that their phenomenology is filled with dynamic content. In the second emptiness of the world stage, the practitioner is encouraged to see that the manifold of phenomenal content is itself empty and underneath it lies a vast awareness. In the third One Taste stage, the practitioner begins to see that awareness and phenomenal content are always co-present and simultaneous and appreciates the danger of reifying awareness. In fourth stage, the practitioner sees meditation itself as a construct and starts noticing that (an awakened) awareness comes and goes accompanied by phenomenal content. It is this vital post-meditation stage that interests us. Here, the return of awareness is marked as significant and is seen as responsible for the very creation of a limited perspective connecting awareness and bounded phenomenal content. In fact, this significant return of awareness is taken up further by the Dzogchen traditions with the Mahamudra yogas acting as a base of operations. We mention all this to point out the crucial role played by the post-meditation stage in Mahamudra: the self or a perspective, awareness and phenomenal content all return together and then disappear. This mimics the descriptions of Strawson and Zahavi to such a remarkable degree that it is surprising that we don't see discussions in consciousness studies focused on this concordance. In contrast, we see recent attempts by philosophers such as Garfield to proceed in the opposite direction and discard the thin subject while claiming support from the Buddhist traditions. We show that this approach is misguided and results in not taking either experience or awareness seriously. To summarize, the return of awareness/phenomenal content in a spatio-temporally bounded form cannot be denied. Buddhist Mahamudra explicitly acknowledges this via the metaphor of taking the perspective of the flashlight (and not focusing either on the illuminated content or on the holder of the flashlight). This thin subject has qualia (sensations, perceptions, emotions etc.) and is capable of intentional acts. Situating the thin subject in the physical world instead of eliminating it should therefore be a paramount concern of consciousness studies.
We begin with the assumption that all emergentist approaches are inadequate to solve the hard pro... more We begin with the assumption that all emergentist approaches are inadequate to solve the hard problem of experience. Consequently, it's hard to escape the conclusion that consciousness is fundamental and that some form of panpsychism is true. Unfortunately, panpsychism faces the combination problem – why should proto-experiences combine to form full fledged experiences? Since the combination problem has resisted many attempts, we argue for compositionality as the missing ingredient needed to explain mid level experiences such as ours. Since this is controversial, we carefully present the full argument below. To begin, we assume, following Frege, that experience cannot exist with being accompanied by a subject of experience (SoE). An SoE provides the structural and spatio-temporally bounded “container” for experience and following Strawson is conceived as a thin subject. Thin subjects exhibit a phenomenal unity with different types of phenomenal content (sensations, thoughts etc.) occurring during their temporal existence. Next, following Stoljar, we invoke our ignorance of the true physical as the reason for the explanatory gap between present day physical processes (events, properties) and experience. We are therefore permitted to conceive of thin subjects as physical compositions. Compositionality has been an intensely studied area in the past twenty years. While there is no clear consensus here, we argue, following Koslicki, that a case can be made for a restricted compositionality principle and that thin subjects are physical compositions of a certain natural kind. In this view, SoEs are natural kind objects with a yet to be specified compositionality relation connecting them to the physical world. The specifics of this relation will be detailed by a new physics and at this juncture, all we can provide are guiding metaphors. We suggest that the relation binding an SoE to the physical is akin to the relation between a particle and field. In present day physics, a particle is conceived as a coherent excitation of a field and is spatially and temporally bounded (with the photon being the sole exception). Under the right set of circumstances, a particle coalesces out of a field and dissipates. We suggest that an SoE can be conceived as akin to a particle coalescing out of physical fields, persisting for a brief period of time and then dissipating – in a manner similar to the phenomenology of a thin subject. Experiences are physical properties of SoEs with the constraint (specified by a similarity metric) that SoEs belonging to the same natural kind will have similar experiences. The counter-intuitive aspect of this proposal is the unexpected “complexity” exhibited by SoE particles but we have been prepared for this by the complex behavior of elementary particles in over ninety years of experimental physics. Consequently, while it is odd at first glance to conceive of subjects of experience as particles, the spatial and temporal unity exhibited by particles as opposed to fields and the expectation that SoEs are new kinds of particles, paves the way for cementing this notion. Panpsychism and compositionality are therefore new bedfellows aiding us in resolving the hard problem.