Artificial Intelligence Past, Present, and Future Olac Fuentes Associate Professor Computer Science Department UTEP 1 Artificial Intelligence A definition: • AI is the science and engineering of making intelligent machines 2 Artificial Intelligence A definition: • AI is the science and engineering of making intelligent machines But, what is intelligence? • A very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly, and learn from experience. 3 Artificial Intelligence Another definition: • AI is the science and engineering of making machines that are capable of: – – – – – – Reasoning Representing knowledge Planning Learning Understanding (human) languages Understanding their environment 4 Artificial Intelligence • Weak AI Claim - Machines can possibly act as if they were intelligent • Strong AI Claim - Machines can actually think intelligently 5 Artificial Intelligence Why? 6 Artificial Intelligence Why? – Building an intelligent machine will help us better understand natural intelligence 7 Artificial Intelligence Why? – Building an intelligent machine will help us better understand natural intelligence – An intelligent machine can be used to perform difficult and useful tasks whether it models human intelligence or not 8 Artificial Intelligence Brief History – Field was founded in 1956, initially led by John Mc Carthy, Marvin Minsky, Allen Newell and Herbert Simon (known as the “fourfathers” of A.I.) – Great initial optimism, grandiose objectives (“machines will be capable, within twenty years, of doing any work a man can do” – H. Simon) – Emphasis on symbolic reasoning – Huge government spending – Disappointing results 9 Artificial Intelligence - Brief History The A.I. Winter – 1966: the failure of machine translation, – 1970: the abandonment of connectionism, – 1971−75: DARPA's frustration with the Speech Understanding Research program at Carnegie Mellon University, – 1973: the large decrease in AI research in the United Kingdom in response to the Lighthill report, – 1973−74: DARPA's cutbacks to academic AI research in general, – 1987: the collapse of the Lisp machine market, – 1988: the cancellation of new spending on AI by the Strategic Computing Initiative, – 1993: expert systems slowly reaching the bottom, – 1990s: the quiet disappearance of the fifth-generation computer project's original goals, 10 Artificial Intelligence Brief History – The Comeback – Rebirth of Connectionism • The backpropagation algorithm (Hinton and others, 1986, PDP group) – Machine learning becomes usable • The ID3 and C4.5 algorithms – decision trees for the masses - R. Quinlan, 86 • Increased computing power • Increased availability of data in electronic form – Behavior-based (or “emerging”) A.I. • “A robust layered control system for a mobile robot” – R. Brooks, 85 • “Intelligence is in the eye of the beholder”, “The world is its own best model”, “Elephants don’t play chess”, “We don’t need no representation” • Agent-based architectures (Maes, and many others) – Active Vision • The goal of machine perception is not to build a 3D model of the world, but to extract information to perform useful tasks (D. Ballard, Y. Aloimonos) 11 Artificial Intelligence Brief History – Present Times –Realistic expectations –Lots of useful applications –Research divided into subareas (vision, learning, NLP, planning, etc.) –Little work on overall intelligence 12 Artificial Intelligence The Old Times The pursuit of “General AI” Objective: Build a machine that exhibits ALL of the AI features 13 Old Times – The Turing Test How do we know when AI research has succeed? When a program that can consistently pass the Turing test is written. 14 Old Times – The Turing Test A human judge engages in a natural language conversation with one human and one machine, each of which tries to appear human; if the judge cannot reliably tell which is which, then the machine is said to pass the test. 15 Old Times – The Turing Test Problems with the Turing test: 16 Old Times – The Turing Test Problems with the Turing test: • Human intelligence vs. general intelligence – Computer is expected to exhibit undesirable human behaviors – Computer may fail for being too smart 17 Old Times – The Turing Test Problems with the Turing test: • Human intelligence vs. general intelligence – Computer is expected to exhibit undesirable human behaviors – Computer may fail for being too smart • Real intelligence vs. simulated intelligence 18 Old Times – The Turing Test Problems with the Turing test: • Human intelligence vs. general intelligence – Computer is expected to exhibit undesirable human behaviors – Computer may fail for being too smart • Real intelligence vs. simulated intelligence • Do we really need a machine that passes it? 19 Old Times – The Turing Test Problems with the Turing test: • Human intelligence vs. general intelligence – Computer is expected to exhibit undesirable human behaviors – Computer may fail for being too smart • Real intelligence vs. simulated intelligence • Do we really need a machine that passes it? • Testing the machine vs. testing the judge 20 Old Times – The Turing Test Problems with the Turing test: • Human intelligence vs. general intelligence – Computer is expected to exhibit undesirable human behaviors – Computer may fail for being too smart • • • • Real intelligence vs. simulated intelligence Do we really need a machine that passes it? Testing the machine vs. testing the judge Too hard! – Very useful applications can be built that don’t pass the Turing test 21 More Recent Research Goal: Build “intelligent” programs that are useful for a particular task Normally restricted to one target intelligent behavior. Thus AI has been broken into several sub-areas: – Machine learning – Robotics – Computer vision – Natural language processing – Knowledge representation and reasoning 22 What has AI done for us? State of the Art It has provided computers that are able to: • Learn (some simple concepts and tasks) • Allow robots to navigate autonomously (in simplified environments) • Understand images (of restricted predefined types) • Understand human languages (some of them, mostly written, with limited vocabularies) • Reason (using brute force, in very restricted domains) 23 What has AI done for us? Machine Learning – Netflix movie recommender system Very active research area – – – – – – Extract statistical regularities from data Find decision boundaries Find decision rules Imitate human brain Imitate biological evolution Combine several approaches 24 What has AI done for us? Machine Learning – Netflix movie recommender system Idea: • After returning a movie, user assigns a grade to it (from 1 to 5) • Given (millions) of records of users, movies and grades, and the pattern of grades assigned by the user, the system presents a list of movies the user is likely to grade highly 25 What has AI done for us? Robotics - Stanley, a self-driving car 26 What has AI done for us? Robotics - Stanley, a self-driving car What does Stanley learn? A mapping from sensory inputs to driving commands 27 What has AI done for us? Robotics - Lexus self-parking system 28 What has AI done for us? Computer Vision - Face Detecting Cameras 29 What has AI done for us? Computer Vision - Face Detecting Cameras 30 What has AI done for us? Reasoning Successful applications: • Route planning systems • Game playing programs 31 What has AI done for us? Reasoning The Zohirushi Neuro Fuzzy® Rice Cooker & Warmer features advanced Neuro Fuzzy® logic technology, which allows the rice cooker to 'think' for itself and make fine adjustments to temperature and heating time to cook perfect rice every time. 32 What has AI done for us? Natural language processing Successful applications: • Dictation systems • Text-to-speech systems • Text classification • Automated summarization • Automated translation 33 What has AI done for us? Natural language processing Automated Translation Original English Text: The Dodgers became the fifth team in modern major league history to win a game in which they didn't get a hit, defeating the Angels 1-0. Weaver's error on a slow roller led to an unearned run by the Dodgers in the fifth. What has AI done for us? Natural language processing Automated Translation Original English Text: The Dodgers became the fifth team in modern major league history to win a game in which they didn't get a hit, defeating the Angels 1-0. Weaver's error on a slow roller led to an unearned run by the Dodgers in the fifth. Translation to Spanish (by Google - 2009) Los Dodgers se convirtió en el quinto equipo en la moderna historia de las ligas mayores para ganar un juego en el que no obtener una respuesta positiva, derrotando a los Ángeles 1-0. Weaver's error en un lento rodillo dado lugar a un descontados no correr por la Dodgers en el quinto. What has AI done for us? Natural language processing Automated Translation Translation to Spanish (by Google - 2009) Los Dodgers se convirtió en el quinto equipo en la moderna historia de las ligas mayores para ganar un juego en el que no obtener una respuesta positiva, derrotando a los Ángeles 1-0. Weaver's error en un lento rodillo dado lugar a un descontados no correr por la Dodgers en el quinto. What has AI done for us? Natural language processing Automated Translation Translation to Spanish (by Google – 2009) Los Dodgers se convirtió en el quinto equipo en la moderna historia de las ligas mayores para ganar un juego en el que no obtener una respuesta positiva, derrotando a los Ángeles 1-0. Weaver's error en un lento rodillo dado lugar a un descontados no correr por la Dodgers en el quinto. Translation back to English (by Google – 2009) The Dodgers became the fifth equipment in the modern history of the leagues majors to gain a game in which not to obtain a positive answer, defeating to Los Angeles 1-0. Weaver' s error in a slow given rise roller to discounting not to run by the Dodgers in fifth. What has AI done for us? Natural language processing Automated Translation Original English Text: The Dodgers became the fifth team in modern major league history to win a game in which they didn't get a hit, defeating the Angels 1-0. Weaver's error on a slow roller led to an unearned run by the Dodgers in the fifth. What has AI done for us? Natural language processing Automated Translation Original English Text: The Dodgers became the fifth team in modern major league history to win a game in which they didn't get a hit, defeating the Angels 1-0. Weaver's error on a slow roller led to an unearned run by the Dodgers in the fifth. Translation to Spanish (by Google - 2010) Los Dodgers se convirtió en el quinto equipo en la historia moderna de Grandes Ligas en ganar un juego en el que no recibieron una respuesta positiva, derrotando a los Angelinos 1-0. error de Weaver en una rola lenta dio lugar a una carrera sucia por los Dodgers en el quinto. What has AI done for us? Natural language processing Automated Translation Translation to Spanish (by Google – 2010) Los Dodgers se convirtió en el quinto equipo en la historia moderna de Grandes Ligas en ganar un juego en el que no recibieron una respuesta positiva, derrotando a los Angelinos 1-0. error de Weaver en una rola lenta dio lugar a una carrera sucia por los Dodgers en el quinto. Translation back to English (by Google – 2010) The Dodgers became the fifth side in the modern history of baseball to win a game that did not get a hit, defeating the Angels 1-0. Weaver's error on a slow roller led to an unearned run for the Dodgers in the fifth. The Future of AI 41 The Future of AI Making predictions is hard, especially about the future - Yogi Berra 42 The Future of AI Making predictions is hard, especially about the future - Yogi Berra But… • Continued progress expected • Greater complexity and autonomy • New enabling technology - Metalearning • Once human-level intelligence is attained, it will be quickly surpassed 43 Conclusions 44 Conclusions • Artificial Intelligence has made a great deal of progress since its inception in the 1950s 45 Conclusions • Artificial Intelligence has made a great deal of progress since its inception in the 1950s • The goal of general AI has been abandoned (at least temporarily) 46 Conclusions • Artificial Intelligence has made a great deal of progress since its inception in the 1950s • The goal of general AI has been abandoned (at least temporarily) • Useful applications have appeared in all subfields of AI, including: Machine learning, computer vision, robotics, natural language processing and knowledge representation 47 Conclusions • Artificial Intelligence has made a great deal of progress since its inception in the 1950s • The goal of general AI has been abandoned (at least temporarily) • Useful applications have appeared in all subfields of AI, including: Machine learning, computer vision, robotics, natural language processing and knowledge representation • The field continues to evolve rapidly 48 Conclusions • Artificial Intelligence has made a great deal of progress since its inception in the 1950s • The goal of general AI has been abandoned (at least temporarily) • Useful applications have appeared in all subfields of AI, including: Machine learning, computer vision, robotics, natural language processing and knowledge representation • The field continues to evolve rapidly • Increased complexity and unpredictability of AI programs will raise important ethics issues and concerns 49 AI and Psychology Some questions/issues: • Can A.I. algorithms be used to model natural intelligence? • How can we exploit our knowledge of human intelligence to develop artificially intelligent systems? • Can psychology help settle the Strong A.I. vs. Weak A.I. debate? 50 THANKS! Questions? For more info: http://www.cs.utep.edu/ofuentes/ 51 UTEP’s Vision and Learning Laboratory Our goals: Programming computers to see Programming computers to learn 52 UTEP’s Vision and Learning Laboratory A Sample of Current Research Projects • • • • • • • • Transfer learning using deep neural networks Image super-resolution Image compression Tracking multiple nearly-identical objects Vision with foveal cameras Medical image analysis Astronomical data analysis Predicting RNA folding 53 Machine Learning Why? Scientific Reason: • Learning is arguably the most important feature of intelligence. • If we want to understand and replicate intelligent behavior, the ability to learn is indispensable. 54 Machine Learning Why? Engineering Reason: • Programs that allow computers to learn are the only practical way of solving a wide variety of very difficult problems. 55 Machine Learning The key enabling technology of AI Problem Solving in Computer Science 56 Machine Learning The key enabling technology of AI Problem Solving in Computer Science • Traditional Approach – Write a detailed sequence of instructions (a program) that tells the computer how to solve the problem. 57 Machine Learning The key enabling technology of AI Problem Solving in Computer Science • Traditional Approach – Write a detailed sequence of instructions (a program) that tells the computer how to solve the problem. • Machine Learning Approach – Give the computer examples of desired results and let it learn how to solve the problem. 58 Machine Learning The key enabling technology of AI Problem Solving in Computer Science • Traditional Approach – Write a detailed sequence of instructions (a program) that tells the computer how to solve the problem. • Machine Learning Approach – Give the computer examples of desired results and let it learn how to solve the problem. – Advantage: It allows to solve problems that we can’t solve with the traditional approach 59 Machine Learning The key enabling technology of AI Problem Solving in Computer Science • Traditional Approach – Write a detailed sequence of instructions (a program) that tells the computer how to solve the problem. • Machine Learning Approach – Give the computer examples of desired results and let it learn how to solve the problem. – Advantage: It allows to solve problems that we can’t solve with the traditional approach – Most applications in other AI areas are based on machine learning 60 Background: Artificial Neural Networks Idea: Imitate the information processing capabilities of the central nervous system using a large set of simple parallel non-linear units (“artificial neurons”) 61 Background: Artificial Neural Networks The output of a neuron is given by a combination of its inputs and its associated weights We use a set of examples to adjust the weights to allow the network to give the correct output – this is called training the network We use the trained network to solve problems! 62 Artificial Neural Networks Face Recognition Input: Pixel intensities Output: Vicente Fox! Input: Pixel intensities Output: Angelina Jolie! 63 Artificial Neural Networks Classification of Infant Cry Input: Sound intensities over time Output: Hungry Input: Sound intensities over time Output: Pain 64 Artificial Neural Networks Driving Autonomous Vehicles Input: Pixel intensities Output: Left Input: Pixel intensities Output: Straight Input: Pixel intensities Output: Right 65 Background: Artificial Neural Networks Advantages: • Can approximate many types of functions (real-valued, discrete-valued, vector-valued) • Relatively insensitive to noise Disadvantages: • Training times can be long • Overfitting –network “memorizes” training data and is unable to generalize 66 Transfer learning using deep neural networks Research Question: Can we take advantage of previously-acquired knowledge in order to learn to solve a new task more quickly and/or with less training data? It works for humans: - Knowing Spanish helps to learn Portuguese - A tennis player can easily learn to play squash 67 Transfer learning using deep neural networks Idea # 1: • Use a network with many layers • Train network for a task • Retrain only the last one or two layers in order to learn a new but similar task Idea # 2: • • • • Use output layer with many neurons Assign randomly chosen values to output neurons for each class Train network for a task When new class is added to task, find average value in output layer and assign that as the label for the class 68 Transfer learning using deep neural networks Idea # 1: • Use a network with many layers • Train network for a task • Retrain only the last one or two layers in order to learn a new but similar task Results • We trained a network to recognize handwritten letters • We can re-train a network to recognize digits using less than 5% of the time and training examples Potential Applications • Speech recognition • Face recognition 69 Transfer learning using deep neural networks Idea # 2: • • • • Use output layer with many neurons Assign randomly chosen values to output neurons for each class Train network for a task When new class is added to task, find average value in output layer and assign that as the label for the class Results • We trained a network to recognize handwritten letters • Network can recognize digits without any retraining Potential Applications • Flexible face recognition systems • Language models with unlimited vocabulary 70 Image Super-resolution Research Question: Can we increase the resolution of an image of a known class (say faces, or hand-written text) in software? That is, given a low-resolution (LR) image of an object, can we infer its appearance in highresolution (HR)? Idea: Crate many pairs of (LR,HR) images Learn function from LR to HR (the opposite is trivial) When given a LR image, apply learned function to increase resolution 71 Image Super-resolution LR input image Generated image Original HR image 72 Image Super-resolution Theory and Algorithms Decouple high-resolution face image to two parts = + I Hg I Hl I H — high resolution face image I Hg — global face I Hl — local face IH Two-step Bayesian inference I H* arg max p ( I L | I H ) p ( I H ) IH IH ? arg max p ( I L | I Hg , I Hl I Hg , I Hl ) p ( I Hg , I Hl ) arg max p ( I L | I Hg ) p ( I Hg ) p ( I Hl | I Hg ) IL I Hg , I Hl 1. Inferring global face 1. Inferring global face g* I H arg max p( I L | I Hg ) p( I Hg ) I Hg * 2. Inferring local face 2. Inferring local face I Hl * arg max p ( I Hl | I Hg * ) I Hl * Finally adding them together Finally adding them together I H* I Hl * I Hg * 73 Image Super-resolution Our Contributions: • Improved image alignment: k-nearest-neighbors warping function • More efficient reconstruction: a stochastic algorithm to build local model 74 Image Super-resolution Experimental results (a) (b) (c) (d) (e) (a) LR image Restored full face. (c) Restored global face. (d) Interpolated face. (e) Original face. (f) Restored local face. (f) 75 Compression of Medical Images using Super-resolution Observation: if we can derive the HR image from the LR one, then we don’t need to store the HR image! Idea: • Segment image into regions of high, medium and low importance • Compress low importance pixels to a single bit • Compress/decompress medium importance pixels using super-resolution • Compress/decompress high importance area using lossless compression algorithm such as jpeg2000 76 Compression of Medical Images using Super-resolution a) Original mammogram; b), c) and d) show different compression/decompression results for different compression parameters 77 Compression of Medical Images using Super-resolution Compression Method PSNR Compression Ratio JPEG 2000 41.95 80:1 Lossless JPEG infinite 3:1 Our method 35.90 20480:1 Experimental results 78 Tracking Nearly Identical Objects Problem: Given a video with multiple moving objects that are similar, determine the trajectories of each individual object 79 Tracking Nearly Identical Objects 80 Tracking Nearly Identical Objects Approach: • Build probabilistic models of motion of objects from training video • Find objects on consecutive frames f(i) and f(i+1) • Use a backtracking search algorithm to find the set of matches that maximizes probability, given models Application: Tracking flies – experiments to determine the effect of alcohol ingestion on groups of flies 81 Tracking Nearly Identical Objects 82 Tracking Nearly Identical Objects 83 Traffic Sign Inspection and Tracking Tracking – Locating an object of interest in a sequence of images, despite variations in size and appearance 84 Machine Learning in Science • Problem: Gathering scientific data is easy, gaining knowledge from them is not! – Huge amounts of data gathered with automated devices – Digital sky surveys, medical databases, particle physics experiments, seismic data – Data easily available through the Internet – Not enough scientists to fully exploit data • Thus, there's a need for automated methods to classify and analyze the data and to derive knowledge and insight from them. • Machine learning offers a very promising methodology to attain these goals 85 Example: Estimation of Stellar Atmospheric Parameters from Spectra What's a spectrum? A plot of energy flux against wavelength. It shows the combination of black body radiation (originated in the core) and absorption lines (originated in the atmosphere) I 86 Estimation of Stellar Atmospheric Parameters • Quantum theory tells us that an atom can absorb energy only at certain discrete wavelengths. • Thus, we can view an absorption line as the signature of the atom, ion or molecule that produces it. • An expert astronomer can estimate the properties of the star’s atmosphere from the strength of the absorption lines. • In particular, the effective temperature, surface gravity and metallicity can be estimated from the strength of absorption lines. 87 Estimation of Stellar Atmospheric Parameters - Problem: Too many stars! 88 Experimental Results Estimation of Stellar Atmospheric Parameters 89 Experimental Results Estimation of Stellar Atmospheric Parameters Ensemble LWLR OC Error Reduction Teff[k] 143.33 126.88 11.5% Log g[dex] 0.3221 0.2833 12% Fe/H 0.223 0.172 22.9% 90 Vision with foveal cameras Mission: transmit faces 28x37 chip 76x150 chip Before transmission: •Tune/enhance resolution •Compress appropriately 46x35 full frame Sampled from 3600x2700 sensor 91 Challenge – where to foveate? Problem: Foveation is useful as long as we can effectively select the image regions where super-resolution should be applied. Our Approach: Use motion as a first trigger of higher resolution Learn from multiple positive and negative examples of objects of the class of interest (e.g. faces, pedestrians, vehicles) Challenges: – The same algorithm must be applicable to widely varying object classes – Choice of features – Choice of (negative) examples – Combination of detectors Results: • We have built systems that detect over 90% of the faces in images, while yielding a false-positive rate of about 0.00001% • Our methods can easily be implemented in systolic hardware 92 Foveating on faces 93 Foveating on faces 94 Motion-triggered Foveation 95 THANKS! For more info: http://www.cs.utep.edu/ofuentes/ 96 Acknowledgements This work was actually done by: • Steven Gutstein • Jason Zheng • Geovany Ramirez • Diego Aguirre • Joel Quintana • Peter Kelley • Manali Chakraborty • Trilce Estrada 97