Trifocal Relative Pose from Lines at Points and its Efficient Solution

We present a new minimal problem for relative pose estimation mixing point features with lines incident at points observed in three views and its efficient homotopy continuation solver. We demonstrate the generality of the approach by analyzing and solving an additional problem with mixed point and line correspondences in three views. The minimal problems include correspondences of (i) three points and one line and (ii) three points and two lines through two of the points which is reported and analyzed here for the first time. These are difficult to solve, as they have 216 and - as shown here - 312 solutions, but cover important practical situations when line and point features appear together, e.g., in urban scenes or when observing curves. We demonstrate that even such difficult problems can be solved robustly using a suitable homotopy continuation technique and we provide an implementation optimized for minimal problems that can be integrated into engineering applications. Our simulated and real experiments demonstrate our solvers in the camera geometry computation task in structure from motion. We show that new solvers allow for reconstructing challenging scenes where the standard two-view initialization of structure from motion fails.Comment: This material is based upon work supported by the National Science Foundation under Grant No. DMS-1439786 while most authors were in residence at Brown University's Institute for Computational and Experimental Research in Mathematics -- ICERM, in Providence, R

Interpenetrating Waves and Multiple Generation Shocks via the CEDT

This volume contains papers presented at the Third International Workshop on Visual Form. It covers the most important topics of current interest in the field, presenting an updated collection of results achieved by leading academic and industrial research groups from several countries. The book contains invited lectures and research papers dealing with theoretical and applicative aspects of shape perception, representation, decomposition, description and recognition, as well as related topics

Conservation-Minded Evolution of Shape

©1990 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or distribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.DOI: 10.1109/ISIC.1990.128457Presented at the 5th IEEE International Symposium on Intelligent Control, 5-7 September 1990, Philadelphia, PAMost natural and artificial systems rely heavily on vision to recognize, manipulate, and navigate within a world of objects. Although shape is a key element in this process, its representation and analysis have proved to be a difficult, multifaceted problem. A framework, based on conservation laws, which gives rise to computational elements for shape parts, protrusions, and bends, is proposed. The computation takes place in the context of a reaction-diffusion space and is highly robust. This scheme is ideally suited to object recognition and has applications in areas ranging from robotics to the psychology and the physiology of form

The Crossroads of Wellness and Second Victim Syndrome: Identifying Factors that Alter the Pathway of Caregiver Recovery Following an Unanticipated Adverse Patient Outcome

Introduction: Second Victim Syndrome (SVS) describes the phenomenon in which a caregiver experiences a traumatic psychological and emotional response to an adverse patient event or medical error. Using quantitative survey analysis, we aim to better understand the personal factors that affect SVS development and recovery. Methods: Caregivers at a small urban academic medical center who had experienced an adverse patient event in the past six months were invited to take part in this institution-wide, voluntary, quantitative, cross-sectional study. Three surveys were administered; the Holmes-Rahe Life Stress Inventory (HRLSI) was used as a surrogate to measure stressful life events. The Impact of Event Scale-Revised (IES-R) was used as a measure of the stress a provider senses following a traumatic event. The Second Victim Experience and Support Tool (SVEST) was used to assess the medical provider’s emotional response and level of institutional support in response to an adverse clinical event. Results: Analysis of SVEST vs. IES-R demonstrated that respondents with greater self-perception of personal distress reported increased psychological (p=0.0008) and physical (p=0.0015) distress. Respondents who reported higher HRLSI scores had a greater perception that non-work-related support (p=0.04) such as family support was inadequate; however, these respondents were less likely to perceive institutional support (p=0.04) as inadequate. The results indicate that caregivers with more perceived life stresses believe that they do not have strong non-work-related support services, which is a known protective factor; thus, they may perceive any institutional support as more adequate. Conclusion: This study suggests that personal life risk factors, institutional support, and non-work related support may play an important role in the development of SVS and the perception of stress and wellness in the setting of SVS

Symmetry Maps of Free-Form Curve Segments Via Wave Propagation

This paper presents an approach for computing the symmetries (skeletons) of an edge map consisting of a collection of curve segments. This approach is a combination of analytic computations in the style of computational geometry and discrete propagations on a grid in the style of the numerical solutions of PDE's. Specifically, waves from each of the initial curve segments are initialized and propagated as a discrete wavefront along discrete directions. In addition, to avoid error built up due to the discrete nature of propagation, shockwaves are detected and explicitly propagated along a secondary dynamic grid. The propagation of shockwaves, integrated with the propagation of the wavefront along discrete directions, leads to an exact simulation of propagation by the Eikonal equation. The resulting symmetries are simply the collection of shockwaves formed in this process which can be manipulated locally, exactly, and efficiently under local changes in an edge map (gap completion, remova..

Conceptualizing Chemistry in Three Layers

We will devise a system of evaluating published chemistry lab activities based on the extent to which they incorporate modeling into their instruction. We will create a dual system of evaluating modeling as a component of the labs. First, we will use Johnstone’s (1991) conceptualization of chemistry phenomena occurring at three different levels: macroscopic, sub-microscopic, and representational. Second, we will use a modeling framework based on White, Collins & Frederiksen (2011), which describes models in chemistry as having five characteristics: accuracy, coherence, generality, parsimony, and usefulness