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Texas A&M University-Corpus Christi Division of Near Shore Research Present Trends in the Application of Artificial Intelligence to Environmental Systems Account of 3rd Conference on AI Applications to Environmental Science AI Techniques/Disciplines Texas A&M University-Corpus Christi Division of Near Shore Research • Genetic Algorithms • Neural Networks • Support Vector Machines (generalized version of NNs for image analysis) • Expert Systems • Fuzzy Logic Genetic Algorithms Texas A&M University-Corpus Christi Division of Near Shore Research • GA’s are being used for a number of environmental applications – – – – – – Calibrating water quality models Managing groundwater Astrophysics Source of air pollutant Predatory-Prey model Inverse problems in general Genetic Algorithms (2) Texas A&M University-Corpus Christi Division of Near Shore Research • Key to application to Environmental Science problems is to set the GA as an optimization problem • Non linear differential equations can be approached using GA Neural Networks Texas A&M University-Corpus Christi Division of Near Shore Research • Increasingly used by NCEP/NOAA/NASA and European Agencies to speed up computationally expensive tasks (NN can be orders of magnitude faster than classic algorithms) • Use of NNs to correct model biases • Use of NNs for predictive learning (system imitation) Neural Networks (2) Texas A&M University-Corpus Christi Division of Near Shore Research • NN for predictive learning: choosing the “best” model for a given loss function • “Do not solve a given problem by indirectly solving a more general and more complicated problem as an intermediary step” • Possible problems for NNs when the size of the problems become to large (atmospheric models) General NN Techniques Texas A&M University-Corpus Christi Division of Near Shore Research • Our techniques are very much in line with other modelers (choice of model parameters, normalization, model evaluation, etc.) • Use of PCA analysis to identify smaller more optimum input decks • Use of NNs for non linear PCA analysis Discussion Item (Caren Marzban) Texas A&M University-Corpus Christi Division of Near Shore Research • Recognition that the parameters of AI models generally do not have a physical significance • In particular there is no physical meaning in the biases and weights of a neural network • Question/Hypothesis: The parameters of any non linear models do not provide insight into the physics of the system Support Vector Machines Texas A&M University-Corpus Christi Division of Near Shore Research • Relatively new technique which vectorizes pictures/maps and uses a NN type methodology to extract features • uses kernel functions • Also kernel PCA, kernel Gram-Schmidt, Bayes Point Machines, Relevance and Leverage Vector Machines, are some of the other algorithms that make crucial use of kernels for problems of classification, regression, density estimation, novelty detection and clustering Support Vector Machines (2) Texas A&M University-Corpus Christi Division of Near Shore Research • For classification, SVMs operate by finding a hypersurface which attempts to split the positive examples from the negative examples. The split will be chosen to have the largest distance from the hypersurface to the nearest of the positive and negative examples. Texas A&M University-Corpus Christi Division of Near Shore Research http://www.computer.org/intelligent/ex1998/pdf/x4018.pdf Texas A&M University-Corpus Christi Division of Near Shore Research http://www.computer.org/intelligent/ex1998/pdf/x4018.pdf General Issues Texas A&M University-Corpus Christi Division of Near Shore Research • AI techniques are increasingly used to make short to medium term forecasts (sometimes fractions of hours) when large amounts of data are available • Usual forecasting methodologies have trouble for short term forecasts • Harris Corporation is implementing a ceiling and visibility fuzzy logic tool for the FAA Groundwater Issues Texas A&M University-Corpus Christi Division of Near Shore Research • Population growth and possible global change affects/will affect potable water supply including groundwater supply • Decision making is at the (very) local level and relatively uncoordinated (likelihood of conflicts) • It takes 20-25 years to go from the planning to the realization of a new reservoir Bush Administration on Climate Change Texas A&M University-Corpus Christi Division of Near Shore Research • Global climate change recognized as a capstone issue of our generation by the Bush administration • Climate change program ~ 1.7 bio/year • 4 part focus: – – – – Science Observation and Data Decision support resources Outreach and Education • Core solutions to the problem will be technological breakthroughs Scatterometry Overview: Ocean Circulation Scatterometer high resolution, extensive, and frequent wind velocity measurements are Texas A&M University-Corpus Christi Division of Near Shore Research used to understand upper ocean circulation from regional to global scales • Wind stress is the largest momentum input to ocean • Wind stress curl drives large-scale upper ocean currents • Small-scale wind variability modifies large-scale ocean circulation • Coastal regions exhibit amplified physical/biological response • Wind forcing complements dynamic and thermodynamic response measurements Winds & Water, Weather & Waves: Satellite Scatterometry, M.H. Freilich, AMS Short Course, February, 2003 Scatterometry Overview: Meteorology All-weather surface wind measurements provide Texas A&M for University-Corpus Christi Divisionresearch of Near Shore Research unique information atmospheric and operations Winds & Water, Weather & Waves: Satellite Scatterometry, M.H. Freilich, AMS Short Course, February, 2003 Hurricane Dora QuikSCAT -- 10 August 1999 Global backscatter and ocean vector winds < 11 hour coverage Texas A&M University-Corpus Christi Division of Near Shore Research M. H. Freilich COAS/OSU W. L. Jones UCF Winds & Water, Weather & Waves: Satellite Scatterometry, M.H. Freilich, AMS Short Course, February, 2003 WIND MEASUREMENTS: Mission Schedules Texas A&M University-Corpus Christi Division of Near Shore Research 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 [SSM/I, SSMIS] QSCAT SWS/ADEOS-II SWS/GCOM-B ERS-2 ASCAT/METOP WINDSAT CMIS/NPOESS