Planning & Scheduling
Solving the Torpedo Scheduling Problem
Geiger, Martin Josef, Kletzander, Lucas, Musliu, Nysret
The article presents a solution approach for the Torpedo Scheduling Problem, an operational planning problem found in steel production. The problem consists of the integrated scheduling and routing of torpedo cars, i. e. steel transporting vehicles, from a blast furnace to steel converters. In the continuous metallurgic transformation of iron into steel, the discrete transportation step of molten iron must be planned with considerable care in order to ensure a continuous material flow. The problem is solved by a Simulated Annealing algorithm, coupled with an approach of reducing the set of feasible material assignments. The latter is based on logical reductions and lower bound calculations on the number of torpedo cars. Experimental investigations are performed on a larger number of problem instances, which stem from the 2016 implementation challenge of the Association of Constraint Programming (ACP). Our approach was ranked first (joint first place) in the 2016 ACP challenge and found optimal solutions for all used instances in this challenge.
Lead Big Data Administrator - IoT BigData Jobs
At IHG we employ people who apply the same amount of care and passion to their jobs as they do their hobbies โ people who put our guests at the heart of everything they do. And we're looking for more people like this to join our friendly and professional team. Key responsibilities of the role include: design and implementation of real time applications for use in a multi-platform environment; develop strategies for the continued planning, scheduling, and coordination of system tests for reliability, scalability, and maintainability and monitor test results; ensure that departmental standards are documented, distributed and updated on a regular basis for assigned systems development planning, product performance, support and monitoring; provide technical consultation in new systems development and enhancement of existing systems; participate in structured walkthroughs and technical reviews and act as advisor to Sr. level IT management concerning strategic decisions concerning legacy and new technology. Bachelor's or Master's Degree in a relevant field of work or an equivalent combination of education and work related experience. Typically reports to Manager, Information Technology.
Neural Computing and Applications โ incl. option to publish open access
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Proactive Intention Recognition for Joint Human-Robot Search and Rescue Missions through Monte-Carlo Planning in POMDP Environments
Ognibene, Dimitri, Mirante, Lorenzo, Marchegiani, Letizia
Proactively perceiving others' intentions is a crucial skill to effectively interact in unstructured, dynamic and novel environments. This work proposes a first step towards embedding this skill in support robots for search and rescue missions. Predicting the responders' intentions, indeed, will enable exploration approaches which will identify and prioritise areas that are more relevant for the responder and, thus, for the task, leading to the development of safer, more robust and efficient joint exploration strategies. More specifically, this paper presents an active intention recognition paradigm to perceive, even under sensory constraints, not only the target's position but also the first responder's movements, which can provide information on his/her intentions (e.g. reaching the position where he/she expects the target to be). This mechanism is implemented by employing an extension of Monte-Carlo-based planning techniques for partially observable environments, where the reward function is augmented with an entropy reduction bonus. We test in simulation several configurations of reward augmentation, both information theoretic and not, as well as belief state approximations and obtain substantial improvements over the basic approach.
Task-assisted Motion Planning in Partially Observable Domains
Thomas, Antony, Amatya, Sunny, Mastrogiovanni, Fulvio, Baglietto, Marco
Antony Thomas and Sunny Amatya โ and Fulvio Mastrogiovanni and Marco Baglietto Abstract -- We present an integrated T ask-Motion Planning framework for robot navigation in belief space. Autonomous robots operating in real world complex scenarios require planning in the discrete (task) space and the continuous (motion) space. T o this end, we propose a framework for integrating belief space reasoning within a hybrid task planner . The expressive power of PDDL combined with heuristic-driven semantic attachments performs the propagated and posterior belief estimates while planning. The underlying methodology for the development of the combined hybrid planner is discussed, providing suggestions for improvements and future work. I NTRODUCTION Autonomous robots operating in complex real world scenarios require different levels of planning to execute their tasks. High-level (task) planning helps break down a given set of tasks into a sequence of sub-tasks, actual execution of each of these sub-tasks would require low-level control actions to generate appropriate robot motions. In fact, the dependency between logical and geometrical aspects is pervasive in both task planning and execution. Hence, planning should be performed in the task-motion or the discrete-continuous space. In recent years, combining high-level task planning with low-level motion planning has been a subject of great interest among the Robotics and Artificial Intelligence (AI) community.
Computing Multi-Modal Journey Plans under Uncertainty
Botea, Adi, Kishimoto, Akihiro, Nikolova, Evdokia, Braghin, Stefano, Berlingerio, Michele, Daly, Elizabeth
Multi-modal journey planning, which allows multiple types of transport within a single trip, is becoming increasingly popular, due to a strong practical interest and an increasing availability of data. In real life, transport networks feature uncertainty. Yet, most approaches assume a deterministic environment, making plans more prone to failures such as missed connections and major delays in the arrival. This paper presents an approach to computing optimal contingent plans in multi-modal journey planning. The problem is modeled as a search in an and/or state space. We describe search enhancements used on top of the AO* algorithm. Enhancements include admissible heuristics, multiple types of pruning that preserve the completeness and the optimality, and a hybrid search approach with a deterministic and a nondeterministic search. We demonstrate an NP-hardness result, with the hardness stemming from the dynamically changing distributions of the travel time random variables. We perform a detailed empirical analysis on realistic transport networks from cities such as Montpellier, Rome and Dublin. The results demonstrate the effectiveness of our algorithmic contributions, and the benefits of contingent plans as compared to standard sequential plans, when the arrival and departure times of buses are characterized by uncertainty.
Continuous Relaxation of Symbolic Planner for One-Shot Imitation Learning
Huang, De-An, Xu, Danfei, Zhu, Yuke, Garg, Animesh, Savarese, Silvio, Fei-Fei, Li, Niebles, Juan Carlos
Continuous Relaxation of Symbolic Planner for One-Shot Imitation Learning De-An Huang 1, Danfei Xu 1, Y uke Zhu 1, Animesh Garg 1, 2, Silvio Savarese 1, Li Fei-Fei 1, Juan Carlos Niebles 1 Abstract -- We address one-shot imitation learning, where the goal is to execute a previously unseen task based on a single demonstration. While there has been exciting progress in this direction, most of the approaches still require a few hundred tasks for meta-training, which limits the scalability of the approaches. Our main contribution is to formulate one-shot imitation learning as a symbolic planning problem along with the symbol grounding problem. This formulation disentangles the policy execution from the inter-task generalization and leads to better data efficiency. The key technical challenge is that the symbol grounding is prone to error with limited training data and leads to subsequent symbolic planning failures. We address this challenge by proposing a continuous relaxation of the discrete symbolic planner that directly plans on the probabilistic outputs of the symbol grounding model. Our continuous relaxation of the planner can still leverage the information contained in the probabilistic symbol grounding and significantly improve over the baseline planner for the one-shot imitation learning tasks without using large training data. I NTRODUCTION We are interested in robots that can learn a wide variety of tasks efficiently. Recently, there has been an increasing interest in the one-shot imitation learning problem [1-7], where the goal is to learn to execute a previously unseen task from only a single demonstration of the task. This setting is also referred to as meta-learning [3, 8], where the meta-training stage uses a set of tasks in a given domain to simulate the one-shot testing scenario. This allows the learned model to generalize to previously unseen tasks with a single demonstration in the meta-testing stage. The main shortcoming of these one-shot approaches is that they typically require a large amount of data for meta-training (400 meta-training tasks in [4] and 1000 in [6] for the Block Stacking task [6]) to generalize reliably to unseen tasks.
AI: How It's Transforming Project Management for the Better
Chief Design Officer InEight Dan Patterson founded BASIS, a company that developed an artificial intelligence (AI) planning software tool that was acquired by InEight in 2018. Following the acquisition, Dan became a member of InEight's executive leadership team. He now focuses on expanding upon his vision of creating next generation planning and scheduling software solutions for the construction industry. As a globally recognized project analytics thought leader and software entrepreneur, Dan has more than 20 years of experience building project management software companies, including Pertmaster and Acumen. Throughout his career, Dan has focused on solution innovation and project management, including advanced scheduling, risk management, project analytics and AI.
Towards Explainable AI Planning as a Service
Cashmore, Michael, Collins, Anna, Krarup, Benjamin, Krivic, Senka, Magazzeni, Daniele, Smith, David
Explainable AI is an important area of research within which Explainable Planning is an emerging topic. In this paper, we argue that Explainable Planning can be designed as a service -- that is, as a wrapper around an existing planning system that utilises the existing planner to assist in answering contrastive questions. We introduce a prototype framework to facilitate this, along with some examples of how a planner can be used to address certain types of contrastive questions. We discuss the main advantages and limitations of such an approach and we identify open questions for Explainable Planning as a service that identify several possible research directions.
Unifying System Health Management and Automated Decision Making
Balaban, Edward, Johnson, Stephen B., Kochenderfer, Mykel J.
Health management of complex dynamic systems has evolved from simple automated alarms into a subfield of artificial intelligence with techniques for analyzing off-nominal conditions and generating responses. This evolution took place largely apart from the development of automated system control, planning, and scheduling (generally referred to in this work as decision making). While there have been efforts to establish an information exchange between system health management and decision making, successful practical implementations of integrated architectures remain limited. This article proposes that rather than being treated as connected yet distinct entities, system health management and decision making should be unified in their formulations. Enabled by advances in modeling and algorithms, we believe that a unified approach will increase systems' resilience to faults and improve their effectiveness. We overview the prevalent system health management methodology, illustrate its limitations through numerical examples, and describe a proposed unified approach. We then show how typical system health management concepts are accommodated in the proposed approach without loss of functionality or generality. A computational complexity analysis of the unified approach is also provided.