Object recognition using metric shape

AbstractMost previous studies of 3D shape perception have shown a general inability to visually perceive metric shape. In line with this, studies of object recognition have shown that only qualitative differences, not quantitative or metric ones can be used effectively for object recognition. Recently, Bingham and Lind (2008) found that large perspective changes (⩾45°) allow perception of metric shape and Lee and Bingham (2010) found that this, in turn, allowed accurate feedforward reaches-to-grasp objects varying in metric shape. We now investigated whether this information would allow accurate and effective recognition of objects that vary in respect to metric shape. Both judgment accuracies (d′) and reaction times confirmed that, with the availability of visual information in large perspective changes, recognition of objects using quantitative as compared to qualitative properties was equivalent in accuracy and speed of judgments. The ability to recognize objects based on their metric shape is, therefore, a function of the availability or unavailability of requisite visual information. These issues and results are discussed in the context of the Two Visual System hypothesis of Milner and Goodale (1995, 2006)

Beurling slow and regular variation

We give a new theory of Beurling regular variation ( Part II). This includes the previously known theory of Beurling slow variation ( Part I) to which we contribute by extending Bloom's theorem. Beurling slow variation arose in the classical theory of Karamata slow and regular variation. We show that the Beurling theory includes the Karamata theory

Collective action and market formation: An integrative framework

Research Summary : While extant research recognizes the importance of collective action for market formation, it provides little understanding about when and to what extent collective action is important. In this article, we develop a novel theoretical framework detailing what collective action problems and solutions arise in market formation and under what conditions. Our framework centers on the development of market infrastructure with three key factors that influence the nature and extent of collective action problems: perceived returns to contributions, excludability, and contribution substitutability. We apply our framework to diverse market formation contexts and derive a set of attendant propositions. Finally, we show how collective action problems and solutions evolve during market formation efforts and discuss how our framework contributes to strategic management, entrepreneurship, and organization literatures. Managerial Summary : This article lays out the key considerations that players operating in new markets should contemplate when making nontrivial investments in those spaces. As collective action problems can thwart efforts to establish new markets, we ask: When and under what conditions should market players collaborate rather than act independently? And if players collaborate, how should they coordinate to establish a new market? To address these research questions, we develop a novel generalizable framework of collective action in market formation. Our framework assesses the presence and type of collective action problems that hinder market formation and identifies potential solutions tied to those collective action problems

Automated verification of shape and size properties via separation logic.

Despite their popularity and importance, pointer-based programs remain a major challenge for program verification. In this paper, we propose an automated verification system that is concise, precise and expressive for ensuring the safety of pointer-based programs. Our approach uses user-definable shape predicates to allow programmers to describe a wide range of data structures with their associated size properties. To support automatic verification, we design a new entailment checking procedure that can handle well-founded inductive predicates using unfold/fold reasoning. We have proven the soundness and termination of our verification system, and have built a prototype system

Pseudo Random Forests for Tube Identification

Title from PDF of title page, viewed on March 21, 2016Thesis advisor: Deendayal DinakarpandianVitaIncludes bibliographical references (pages 52-53)Thesis (M.S.)--School of Computing and Engineering. University of Missouri--Kansas City, 2015Random forests are widely used in machine learning as they can potentially offer higher accuracy than individual decision trees by the averaging of multiple independent models. We propose a modification called “Pseudo-random forests” that combines stochastic feature selection with dynamic problem-specific feature generation. As proof of concept, we apply the method to the problem of edge detection and classification in radiographic images. In particular, we use the method to detect feeding tubes in pediatric patients, which are inserted to deliver food and medicine. Since multiple layers of tissues and medical objects are overlaid in a single image, these can be difficult to read on x-rays, even for trained radiologists. The placement of these tubes is critical to the well-being and care of the patient. Automating the recognition of these tubes can help confirm the correct placement of these tubes, as an improperly placed tube could delay treatment or jeopardize the health of the patient. It can also save time by enhancing the visibility of tubes for interpretation by radiologists, as hospitals may have to validate tens to hundreds of these x-rays a day. We report an average recall of 85% for tube pixel identification by using Pseudo-random forests for classification, based on leave-out-one cross-validation. Further improvement is possible by post-processing for tube continuity and the incorporation of other techniques developed as part of the research.Introduction -- Methodology -- Evaluation -- Conclusions and future wor

Asymptotic behavior of the loss probability for an M/G/1/N queue with vacations

In this paper, asymptotic properties of the loss probability are considered for an M/G/1/N queue with server vacations and exhaustive service discipline, denoted by an M/G/1/N -(V, E)-queue. Exact asymptotic rates of the loss probability are obtained for the cases in which the traffic intensity is smaller than, equal to and greater than one, respectively. When the vacation time is zero, the model considered degenerates to the standard M/G/1/N queue. For this standard queueing model, our analysis provides new or extended asymptotic results for the loss probability. In terms of the duality relationship between the M/G/1/N and GI/M/1/N queues, we also provide asymptotic properties for the standard GI/M/1/N model

Amplitude Fine-Structure in the Cepheid P-L Relation I: Amplitude Distribution Across the RR Lyrae Instability Strip Mapped Using the Accessibility Restriction Imposed by the Horizontal Branch

The largest amplitude light curves for both RR Lyrae (RRL) variables and classical Cepheids with periods less than 10 days and greater than 20 days occur at the blue edge of the respective instability strips. It is shown that the equation for the decrease in amplitude with penetration into the strip from the blue edge, and hence the amplitude fine structure within the strip, is the same for RRL and the Cepheids despite their metallicity differences. However, the manifestation of this identity is different between the two classes of variables because the sampling of the RRL strip is restricted by the discrete strip positions of the horizontal branch, a restriction that is absent for the Cepheids in stellar aggregates with a variety of ages. To show the similarity of the strip amplitude fine structure for RRL and Cepheids we make a grid of lines of constant amplitude in the HR diagram of the strip using amplitude data for classical Cepheids in the Galaxy, LMC, and SMC. The model implicit in the grid, that also contains lines of constant period, is used to predict the correlations between period, amplitude, and color for the two Oosterhoff RRL groups in globular clusters. The good agreement of the predictions with the observations using the classical Cepheid amplitude fine structure also for the RRL shows one aspect of the unity of the pulsation processes between the two classes of variables.Comment: 24 pages, 3 tables, 5 figures, submitted to The Astrophysical Journa