Beyond Gr\"obner Bases: Basis Selection for Minimal Solvers

Many computer vision applications require robust estimation of the underlying geometry, in terms of camera motion and 3D structure of the scene. These robust methods often rely on running minimal solvers in a RANSAC framework. In this paper we show how we can make polynomial solvers based on the action matrix method faster, by careful selection of the monomial bases. These monomial bases have traditionally been based on a Gr\"obner basis for the polynomial ideal. Here we describe how we can enumerate all such bases in an efficient way. We also show that going beyond Gr\"obner bases leads to more efficient solvers in many cases. We present a novel basis sampling scheme that we evaluate on a number of problems

Development of Computer Vision-Enhanced Smart Golf Ball Retriever

An automatic vehicle system was developed to assist golfers in collecting golf balls from a practice field. Computer vision methodology was utilized to enhance the detection of golf balls in shallow and/or deep grass regions. The free software OpenCV was used in this project because of its powerful features and supported repository. The homemade golf ball picker was built with a smart recognition function for golf balls and can lock onto targets by itself. A set of field tests was completed in which the rate of golf ball recognition was as high as 95%. We report that this homemade smart golf ball picker can reduce the tremendous amount of labor associated with having to gather golf balls scattered throughout a practice field

Lyapunov functional techniques for the global stability analysis of a delayed SIRS epidemic model

In this paper, we study the global dynamics of a delayed SIRS epidemic model for transmission of disease with a class of nonlinear incidence rates of the form βS(t)∫ 0 hf(τ)G(I(t-τ))dτ. Applying Lyapunov functional techniques in the recent paper [Y. Nakata, Y. Enatsu, Y. Muroya, On the global stability of an SIRS epidemic model with distributed delays, Discrete Contin. Dyn. Syst. Supplement (2011) 11191128], we establish sufficient conditions of the rate of immunity loss for the global asymptotic stability of an endemic equilibrium for the model. In particular, we offer a unified construction of Lyapunov functionals for both cases of R 0 ≤ 1 and R 0 > 1, where R 0 is the basic reproduction number

Parametrically excited nonlinear magnetic rolling pendulum for broadband energy harvesting

This is the author accepted manuscript. The final version is available from AIP Publishing via the DOI in this record.Parametrically excited energy harvesters provide a valuable alternative to directly excited ones. However, linear energy harvesters subjected to parametric excitation usually suffer from narrow bandwidths. This letter proposes a parametrically excited magnetic rolling pendulum (MRP) with intentionally introduced nonlinearity for broadband energy harvesting. The MRP exhibited a first-order parametric resonance with a broadened bandwidth as the excitation acceleration is ≥ 0.2 g (g=9.8 m/s2 ). When excited at 0.5 g in experiment, the parametric resonance was observed in the frequency range between 1.20 and 4.50 with 0 being the natural frequency of 4 Hz. With a peak power output of 3.6 mW, the MRP achieved a half-power bandwidth of 4.8 Hz, which is 120% of its natural frequency. Simulation results suggest that the power output, the bandwidth and the resonance frequency can be manipulated to by varying the magnet dimensions and positions.Engineering and Physical Sciences Research Council (EPSRC