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A novel model-based heuristic for energy optimal motion planning for automated driving

arXiv.org Artificial Intelligence

Predictive motion planning is the key to achieve energy-efficient driving, which is one of the main benefits of automated driving. Researchers have been studying the planning of velocity trajectories, a simpler form of motion planning, for over a decade now and many different methods are available. Dynamic programming has shown to be the most common choice due to its numerical background and ability to include nonlinear constraints and models. Although planning of an optimal trajectory is done in a systematic way, dynamic programming does not use any knowledge about the considered problem to guide the exploration and therefore explores all possible trajectories. A* is a search algorithm which enables using knowledge about the problem to guide the exploration to the most promising solutions first. Knowledge has to be represented in a form of a heuristic function, which gives an optimistic estimate of cost for transitioning to the final state, which is not a straightforward task. This paper presents a novel heuristics incorporating air drag and auxiliary power as well as operational costs of the vehicle, besides kinetic and potential energy and rolling resistance known in the literature. Furthermore, optimal cruising velocity, which depends on vehicle aerodynamic properties and auxiliary power, is derived. Results are compared for different variants of heuristic functions and dynamic programming as well.


Aggregation using input-output trade-off

arXiv.org Machine Learning

In this paper, we introduce a new learning strategy based on a seminal idea of Mojirsheibani (1999, 2000, 2002a, 2002b), who proposed a smart method for combining several classifiers, relying on a consensus notion. In many aggregation methods, the prediction for a new observation x is computed by building a linear or convex combination over a collection of basic estimators r1(x),. .. , rm(x) previously calibrated using a training data set. Mojirsheibani proposes to compute the prediction associated to a new observation by combining selected outputs of the training examples. The output of a training example is selected if some kind of consensus is observed: the predictions computed for the training example with the different machines have to be "similar" to the prediction for the new observation. This approach has been recently extended to the context of regression in Biau et al. (2016). In the original scheme, the agreement condition is actually required to hold for all individual estimators, which appears inadequate if there is one bad initial estimator. In practice, a few disagreements are allowed ; for establishing the theoretical results, the proportion of estimators satisfying the condition is required to tend to 1. In this paper, we propose an alternative procedure, mixing the previous consensus ideas on the predictions with the Euclidean distance computed between entries. This may be seen as an alternative approach allowing to reduce the effect of a possibly bad estimator in the initial list, using a constraint on the inputs. We prove the consistency of our strategy in classification and in regression. We also provide some numerical experiments on simulated and real data to illustrate the benefits of this new aggregation method. On the whole, our practical study shows that our method may perform much better than the original combination technique, and, in particular, exhibit far less variance. We also show on simulated examples that this procedure mixing inputs and outputs is still robust to high dimensional inputs.


Learning Approximate Inference Networks for Structured Prediction

arXiv.org Machine Learning

Structured prediction energy networks (SPENs; Belanger & McCallum 2016) use neural network architectures to define energy functions that can capture arbitrary dependencies among parts of structured outputs. Prior work used gradient descent for inference, relaxing the structured output to a set of continuous variables and then optimizing the energy with respect to them. We replace this use of gradient descent with a neural network trained to approximate structured argmax inference. This "inference network" outputs continuous values that we treat as the output structure. We develop large-margin training criteria for joint training of the structured energy function and inference network. On multi-label classification we report speedups of 10-60x compared to (Belanger et al., 2017) while also improving accuracy. For sequence labeling with simple structured energies, our approach performs comparably to exact inference while being much faster at test time. We then demonstrate improved accuracy by augmenting the energy with a "label language model" that scores entire output label sequences, showing it can improve handling of long-distance dependencies in part-of-speech tagging. Finally, we show how inference networks can replace dynamic programming for test-time inference in conditional random fields, suggestive for their general use for fast inference in structured settings.


How can machine learning create a smarter grid? Open Energi

@machinelearnbot

Across the globe, energy systems are changing and creating unprecedented challenges for the organisations tasked with ensuring the lights stay on. In the UK, National Grid is facing shrinking margins, looming capacity shortages and unpredictable peaks and troughs in energy supply caused by increasing levels of renewable penetration. At the recent Reinventing Energy Summit, Michael Bironneau, Head of Technology Development at Open Energi, explored how the same machine learning techniques that have let machines defeat chess and Go masters, can also be leveraged to orchestrate massive amounts of flexible demand-side capacity โ€“ from industrial equipment, co-generation and battery storage systems โ€“ towards the one goal of creating a smarter grid; one that is cleaner, cheaper, more secure and more efficient. For World Cities Day 2016, Michael talked to Nikita Johnson of Re:work about utilising data science in energy, creating a smarter grid, political challenges, and more. What are the main transformative technologies that will help create a smarter grid?


Neural-Network Quantum States, String-Bond States, and Chiral Topological States

arXiv.org Machine Learning

Neural-Network Quantum States have been recently introduced as an Ansatz for describing the wave function of quantum many-body systems. We show that there are strong connections between Neural-Network Quantum States in the form of Restricted Boltzmann Machines and some classes of Tensor-Network states in arbitrary dimensions. In particular we demonstrate that short-range Restricted Boltzmann Machines are Entangled Plaquette States, while fully connected Restricted Boltzmann Machines are String-Bond States with a nonlocal geometry and low bond dimension. These results shed light on the underlying architecture of Restricted Boltzmann Machines and their efficiency at representing many-body quantum states. String-Bond States also provide a generic way of enhancing the power of Neural-Network Quantum States and a natural generalization to systems with larger local Hilbert space. We compare the advantages and drawbacks of these different classes of states and present a method to combine them together. This allows us to benefit from both the entanglement structure of Tensor Networks and the efficiency of Neural-Network Quantum States into a single Ansatz capable of targeting the wave function of strongly correlated systems. While it remains a challenge to describe states with chiral topological order using traditional Tensor Networks, we show that Neural-Network Quantum States and their String-Bond States extension can describe a lattice Fractional Quantum Hall state exactly. In addition, we provide numerical evidence that Neural-Network Quantum States can approximate a chiral spin liquid with better accuracy than Entangled Plaquette States and local String-Bond States. Our results demonstrate the efficiency of neural networks to describe complex quantum wave functions and pave the way towards the use of String-Bond States as a tool in more traditional machine-learning applications.


Algorithmic detectability threshold of the stochastic block model

arXiv.org Machine Learning

The assumption that the values of model parameters are known or correctly learned, i.e., the Nishimori condition, is one of the requirements for the detectability analysis of the stochastic block model in statistical inference. In practice, however, there is no example demonstrating that we can know the model parameters beforehand, and there is no guarantee that the model parameters can be learned accurately. In this study, we consider the expectation--maximization (EM) algorithm with belief propagation (BP) and derive its algorithmic detectability threshold. Our analysis is not restricted to the community structure, but includes general modular structures. Because the algorithm cannot always learn the planted model parameters correctly, the algorithmic detectability threshold is qualitatively different from the one with the Nishimori condition.


Dyson says it is no longer making plug-in vacuums as it concentrates on cord-free models and air purifiers

The Independent - Tech

Dyson has stopped making full-size, plug-in vacuum cleaners and revealed the products that will replace them. The company is going to focus on its smaller, battery powered models, it said. It made the announcement as it revealed its new Cyclone V10 cordless vacuum, which it says is "why we've stopped developing corded vacuums". At the same time, the company launched the new version of its Pure Cool fan, a purifier that is able to clean things out of the air. Together, Dyson hopes the new products offer the future of "clean home technology". The I.F.O. is fuelled by eight electric engines, which is able to push the flying object to an estimated top speed of about 120mph.


Role of Artificial Intelligence in Environmental Sustainability

#artificialintelligence

In recent years, the environmental issues have triggered debates, discussions, awareness programs and public outrage that have catapulted interest in new technologies, such as Artificial Intelligence. Artificial Intelligence finds application in a wide array of environmental sectors, including resource conservation, wildlife protection, energy management, clean energy, waste management, pollution control and agriculture. Artificial Intelligence (also known as AI) is considered to be the biggest game-changer in the global economy. With its gradual increase in scope and application, it is estimated that by 2030, AI will contribute up to 15.7 trillion of the global economy which is more than the current output of China and India combined. The UN Artificial Intelligence Summit held in Geneva (2017) identified that AI has the potential to accelerate progress towards a dignified life, in peace and prosperity, for all people and have suggested to refocus the use of this technology, that is responsible for self-driving cars and voice/face recognition smart phones, on sustainable development and assisting global efforts to eliminate poverty and hunger, and to protect the environment and conserve natural resources.


Using artificial intelligence and machine learning to manage the electricity grids of the future - Watt-Logic

@machinelearnbot

Existing power grids were designed to transmit electricity over relatively short distances, however, increasingly grids are required to supply major cities from remote offshore wind farms at the same time as integrating local generation. With generators feeding variable amounts of energy from renewable sources into the grid at all voltage levels, it is more difficult to balance supply and demand, and the risks of overloads and fluctuations increase. By 2020 it is estimated that there will be over 50 billion smart devices connected to the internet, creating vast quantities of data which can be harnessed to develop smart systems for managing electricity systems, both at a local and national level to reduce the costs of balancing the electricity system. Relying on traditional linear mathematical models to manage these processes is not feasible, since both the manpower required to encode the models and the computing power to process them would be extremely large. A more real-time approach is required.


Using IIoT to Improve O&G Operations

@machinelearnbot

Digital innovation strategies incorporating the Industrial Internet of Things (IIoT) are top-of-mind for oil and gas operators working to achieve greater productivity and lower costs, even in the face of escalating prices. While the use of connected equipment to help improve operational visibility and control isn't new, advances in software and analytics capacity give operators an entirely new asset for business improvement: data.