Deep Learning and its impact on Operations Research
Title: (How) does Machine Learning impact Operations Research?
Abstract: Machine learning (ML), artificial intelligence (AI), and operations research (OR) are long standing and well established research fields. From a research perspective, there are some natural directions where ML/AI and OR may benefit from each other (and we sketch a few). From an applications perspective, there is the natural ordering of ML/AI (``predictive'') first, OR (``prescriptive'') second, but other cases are conceivable. In this talk, I will discuss some research, applications, and perspectives that I personally find challenging, interesting, exciting, or boring. In particular, a recent surge of interest (``hype'' is not exaggerated) pushed ML and AI into companies/startups and newspapers. Not so much OR. I discuss implications for ``our'' field (which I still think is OR).
Title: The true AI revolution
Abstract: The entire AI revolution is carried by a 30-year old method, which is nowadays referred to as deep learning. The effectiveness of deep learning gave rise to revolutionary image, signal and text recognition performances. In the past five years, impressive strides have been made on these tasks. The successes are mainly attributable to the increased volumes of data and the advances in computational resources. More importantly, the effectiveness of deep learning provides interesting insights into the theory of machine learning. In the presentation, the true AI revolution will be explained and contrasted with the overhyped media image of AI. Starting from a brief history of AI and neural networks, the presentation will zoom in on deep learning and the applied and fundamental research that is fuelling the true AI revolution.
Title: Safe and efficient inspection of railway tracks using deep learning models (Winner Hendrik Lorentz Prize for innovative applications of Data Science)
Abstract:
The Netherlands have the most heavily used railway network in Europe. Every day, travellers make 1.1 million trips by train, 152 million train kilometres in total. This indicates the importance of efficient and thoughtful usage of the railway infrastructure. By monitoring and inspecting the metal railway tracks and the switches, early stage detection of defects is possible, allowing cheaper and timely interventions. This does not only increase the safety level, but also the availability of the heavily used tracks.
Inspectation and CQM have developed an image processing solution for the automatic inspection of railway tracks. In the old days, inspectors had to walk over the tracks to inspect them, which was not without danger. Today, specially equipped trains with cameras make detailed pictures of the railway tracks. This gives us a huge amount of imagery, which has to be looked at by the same inspectors. CQM and Inspectation drastically improve this process using Deep Learning techniques, building a solution for automatic detection of possible defects saving the inspectors a lot of time and allowing cheaper and more frequent railway inspections. The project was awarded the Hendrik Lorentz Prize at the 'Nederlandse Data Science Prijzen' of the Koninklijke Hollandsche Maatschappij der Wetenschappen (KHMW) en Big Data Alliance (BDA).
This talk will be about the practical application, a little bit of the mathematics behind the deep learning model, how to make all of this actually work in practice, and about how to gain trust in the model, not purely using it as a black-box model. But most of all, in this talk, I aim to show that deep learning models are not totally new, maybe scary IA methods, but closely related to methods and models that we as operations researchers, computer scientists and statisticians are familiar with.
Title: How to predict the impact of the energy transition on the electricity network using simulations, data science and machine learning?
Abstract:
The energy system is changing rapidly as renewables are adopted by customers. How can Alliander, which operates over 40.000 kilometers of electricity cables, cope with the vastly increased network peak load? To model these phenomena the data scientists at Alliander used an array of methods: machine learning for estimating spatial adoption of renewables, high performance computation and optimization for grid design and neural network for time series prediction.
Title: Learning to Solve OR Problems
Abstract: Deep learning has revolutionized scientific fields such as "automatic speech recognition" and in "image analysis" by replacing hand designed features with learnable features obtained by training a deep neural network on the raw input signal. These fields have now almost completely converted to a new paradigm where machine learning is driving their stunning progress. In this talk I will argue there is an interesting parallel in the field of OR where optimization algorithms are mostly hand designed rather than learned. The core idea of our proposal is to present many (possibly simulated) example problems and try to discover patterns in how to solve them most effectively. The machine learning tool to achieve this is called reinforcement learning where a policy is trained to maximize total future reward, where reward is defined in terms of the quality of the obtained solution. This approach has been highly successful for solving games such as GO and chess by systems such as AlphaGO and AlphaZero from Deepmind, and we claim it is also applicable to OR. By learning from many problem instances we automatically discover the features and patterns that are useful to solve new problem instances. We successfully developed such a reinforcement learning approach for a family of problems such as the TSP and the VRP which exhibit performance very close to the best hand designed systems. We thus anticipate that (partially) learnable policies for solving combinatorial optimization problems has the potential to make a significant impact in the field of OR.
Joint work with Wouter Kool.
Title: Advanced modelling techniques applied on a Revenue Management solution for a holiday park provider
Abstract:
In a period of 15 months ORTEC has implemented an advanced Revenue Management solution for a leading provider of holiday parks. With over 150 holiday parks, 300.000+ price points need to be monitored and adjusted on a daily basis to offer their loyal and new guests the best price. The Revenue Management solution provides an all-inclusive overview and insights that allow for price adjustments based on consumer, leading to customized prices and ultimately higher revenues. The implemented solution improves traditional forecasting methods by applying machine learning methods (clustering and regression). An intelligent custom solution engine is integrated with a foolproof user interface, a proven dashboarding platform and an existing booking system. Furthermore the solution encourages man-machine interaction, where the combination of human business knowledge and automatic machine calculations leads to great decisions.
The advanced solution is descriptive (data visualization), predictive (forecasting) as well as prescriptive (optimization). The forecasting model uses statistical modeling and machine learning techniques. It detects patterns in historical booking data and applies these patterns to make forecasts, considering both historical bookings and the current bookings at hand. A Linear Programming model is used to solve the optimization problem, which determines prices that maximize total profit.
Before the introduction of this fully automated Revenue Management solution, many manual activities and analyses were required. The manual activities meant focusing on a small selection of price points, especially those points in the far future received less attention. In the new situation, all price points are optimized and, due to the numerous insights, the Revenue Managers can now quickly spot and respond to new trends.