40,836 research outputs found

    Learning-based crop management optimization using multi-stream convolutional neural networks

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    Improving crop management is an essential step towards solving the food security challenge. Despite the advances in precision agriculture, new methods are needed to create decision-support systems to help farmers increase productivity while accounting for environmental impacts and financial risks. This dissertation presents a class of learning-based optimization algorithms for spatial allocation of crop inputs, and a new framework for online coverage path planning with potential use in tasks such as planting and harvesting. The proposed algorithms use Multi-stream Convolutional Neural Networks (MSCNN) to learn relevant spatial features from the environment and use them to optimize the available control inputs. In the crop inputs optimization problem, an MSCNN combines five input variables as in a regression problem to better predict yield. The predictive model is then used as the base of a gradient-ascent algorithm to maximize a custom objective function. To leverage the applicability of this algorithm, a risk-aware version of this method is also proposed. The predictive uncertainty is measured and used as a constraint to comply with different levels of risk-aversion. Experiments with real crop fields demonstrate that this method significantly reduces the yield prediction errors when compared to the state of the art algorithms. Results from the optimization algorithm show an increase in the expected net revenue of up to 6.8% when compared with the status quo management while providing safety bounds. In the coverage path planning framework, an MSCNN agent learns a control policy from demonstrations of paths obtained offline through heuristic algorithms, by using imitation learning. The resulting control policy is further improved through policy-gradient reinforcement learning. Simulations show that the improved control policy outperforms the offline algorithms used during the imitation learning phase, and that the proposed framework can be easily adapted to different cost functions

    Spatial optimization for land use allocation: accounting for sustainability concerns

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    Land-use allocation has long been an important area of research in regional science. Land-use patterns are fundamental to the functions of the biosphere, creating interactions that have substantial impacts on the environment. The spatial arrangement of land uses therefore has implications for activity and travel within a region. Balancing development, economic growth, social interaction, and the protection of the natural environment is at the heart of long-term sustainability. Since land-use patterns are spatially explicit in nature, planning and management necessarily must integrate geographical information system and spatial optimization in meaningful ways if efficiency goals and objectives are to be achieved. This article reviews spatial optimization approaches that have been relied upon to support land-use planning. Characteristics of sustainable land use, particularly compactness, contiguity, and compatibility, are discussed and how spatial optimization techniques have addressed these characteristics are detailed. In particular, objectives and constraints in spatial optimization approaches are examined

    MODELING OF AGRICULTURAL SYSTEMS

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    The authors present an overview of agricultural systems models. Beginning with why systems are modeled and for what purposes, the paper examines types of agricultural systems and associated model types. The broad categories range from pictorial (iconic) models to descriptive analogue models to symbolic (usually mathematical) models. The uses of optimization versus non-optimizing mechanistic models are reviewed, as are the scale and aggregation challenges associated with scaling up from the plant cell to the landscape or from a farm enterprise to a world market supply-demand equilibrium Recent modeling developments include the integration of formerly stand-alone biophysical simulation models, increasingly with a unifying spatial database and often for the purpose of supporting management decisions. Current modeling innovations are estimating and incorporating environmental values and other system interactions. At the community and regional scale, sociological and economic models of rural community structure are being developed to evaluate long-term community viability. The information revolution is bringing new challenges in delivering agricultural systems models over the internet, as well as integrating decision support systems with the new precision agriculture technologies.Farm Management,

    Where should livestock graze? Integrated modeling and optimization to guide grazing management in the Cañete basin, Peru

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    Integrated watershed management allows decision-makers to balance competing objectives, for example agricultural production and protection of water resources. Here, we developed a spatially-explicit approach to support such management in the Cañete watershed, Peru. We modeled the effect of grazing management on three services – livestock production, erosion control, and baseflow provision – and used an optimization routine to simulate landscapes providing the highest level of services. Over the entire watershed, there was a trade-off between livestock productivity and hydrologic services and we identified locations that minimized this trade-off for a given set of preferences. Given the knowledge gaps in ecohydrology and practical constraints not represented in the optimizer, we assessed the robustness of spatial recommendations, i.e. revealing areas most often selected by the optimizer. We conclude with a discussion of the practical decisions involved in using optimization frameworks to inform watershed management programs, and the research needs to better inform the design of such programs

    A General Spatio-Temporal Clustering-Based Non-local Formulation for Multiscale Modeling of Compartmentalized Reservoirs

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    Representing the reservoir as a network of discrete compartments with neighbor and non-neighbor connections is a fast, yet accurate method for analyzing oil and gas reservoirs. Automatic and rapid detection of coarse-scale compartments with distinct static and dynamic properties is an integral part of such high-level reservoir analysis. In this work, we present a hybrid framework specific to reservoir analysis for an automatic detection of clusters in space using spatial and temporal field data, coupled with a physics-based multiscale modeling approach. In this work a novel hybrid approach is presented in which we couple a physics-based non-local modeling framework with data-driven clustering techniques to provide a fast and accurate multiscale modeling of compartmentalized reservoirs. This research also adds to the literature by presenting a comprehensive work on spatio-temporal clustering for reservoir studies applications that well considers the clustering complexities, the intrinsic sparse and noisy nature of the data, and the interpretability of the outcome. Keywords: Artificial Intelligence; Machine Learning; Spatio-Temporal Clustering; Physics-Based Data-Driven Formulation; Multiscale Modelin
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