867 research outputs found

    Optimal control of an epidemic model with inclusion of game theory in vaccination

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    An SIR epidemic model is expanded to include a game theory characterization of changes in human vaccination acceptance. Using the vaccination capacity as a control, we apply optimal control theory to the model and minimize the infected population and social cost simultaneously. We conduct numerical simulations and analyze different scenarios to control COVID-19. Numerical results suggest that the scenario with an optimal control on vaccination capacity may offer a feasible approach for eliminating the epidemic with minimal cost and time. We give a specific vaccination plan based on the optimal control scenario.Bachelor of Scienc

    Spatiotemporal subpixel mapping of time-series images

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    Land cover/land use (LCLU) information extraction from multitemporal sequences of remote sensing imagery is becoming increasingly important. Mixed pixels are a common problem in Landsat and MODIS images that are used widely for LCLU monitoring. Recently developed subpixel mapping (SPM) techniques can extract LCLU information at the subpixel level by dividing mixed pixels into subpixels to which hard classes are then allocated. However, SPM has rarely been studied for time-series images (TSIs). In this paper, a spatiotemporal SPM approach was proposed for SPM of TSIs. In contrast to conventional spatial dependence-based SPM methods, the proposed approach considers simultaneously spatial and temporal dependences, with the former considering the correlation of subpixel classes within each image and the latter considering the correlation of subpixel classes between images in a temporal sequence. The proposed approach was developed assuming the availability of one fine spatial resolution map which exists among the TSIs. The SPM of TSIs is formulated as a constrained optimization problem. Under the coherence constraint imposed by the coarse LCLU proportions, the objective is to maximize the spatiotemporal dependence, which is defined by blending both spatial and temporal dependences. Experiments on three data sets showed that the proposed approach can provide more accurate subpixel resolution TSIs than conventional SPM methods. The SPM results obtained from the TSIs provide an excellent opportunity for LCLU dynamic monitoring and change detection at a finer spatial resolution than the available coarse spatial resolution TSIs
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