Agents
Decentralized dynamic task allocation for UAVs with limited communication range
Pujol-Gonzalez, Marc, Cerquides, Jesus, Meseguer, Pedro, Rodriguez-Aguilar, Juan A., Tambe, Milind
We present the Limited-range Online Routing Problem (LORP), which involves a team of Unmanned Aerial Vehicles (UAVs) with limited communication range that must autonomously coordinate to service task requests. We first show a general approach to cast this dynamic problem as a sequence of decentralized task allocation problems. Then we present two solutions both based on modeling the allocation task as a Markov Random Field to subsequently assess decisions by means of the decentralized Max-Sum algorithm. Our first solution assumes independence between requests, whereas our second solution also considers the UAVs' workloads. A thorough empirical evaluation shows that our workloadbased solution consistently outperforms current state-of-the-art methods in a wide range of scenarios, lowering the average service time up to 16%. In the bestcase scenario there is no gap between our decentralized solution and centralized techniques. In the worst-case scenario we manage to reduce by 25% the gap between current decentralized and centralized techniques. Thus, our solution becomes the method of choice for our problem. Keywords: task allocation, unmanned aerial vehicles, max-sum, decentralized 1. Introduction Unmanned Aerial Vehicles (UAVs) are an attractive technology for largearea surveillance [1]. Today, there are readily available UAVs that are reasonably cheap, have many sensing abilities, exhibit a long endurance and can communicate using radios. UAVs have traditionally been controlled either remotely or by following externally-designed flight plans. Requiring human operators for each UAV implies a large, specialized and expensive human workforce. Likewise, letting UAVs follow externally prepared plans introduces a single point of failure (the planner) and requires UAVs with expensive (satellite) radios to maintain continuous communication with a central station. These constraints are acceptable in some application domains, other applications require more flexible techniques. For instance, consider a force of park rangers tasked with the surveillance of a large natural park. Upon reception of an emergency notification, the rangers must assess the situation as quickly as possible.
APES: a Python toolbox for simulating reinforcement learning environments
Labash, Aqeel, Tampuu, Ardi, Matiisen, Tambet, Aru, Jaan, Vicente, Raul
Assisted by neural networks, reinforcement learning agents have been able to solve increasingly complex tasks over the last years. The simulation environment in which the agents interact is an essential component in any reinforcement learning problem. The environment simulates the dynamics of the agents' world and hence provides feedback to their actions in terms of state observations and external rewards. To ease the design and simulation of such environments this work introduces APES, a highly customizable and open source package in Python to create 2D grid-world environments for reinforcement learning problems. APES equips agents with algorithms to simulate any field of vision, it allows the creation and positioning of items and rewards according to user-defined rules, and supports the interaction of multiple agents.
Using a Game Engine to Simulate Critical Incidents and Data Collection by Autonomous Drones
Smyth, David L., Glavin, Frank G., Madden, Michael G.
Abstract--Using a game engine, we have developed a virtual environment which models important aspects of critical incident scenarios. We focused on modelling phenomena relating to the identification and gathering of key forensic evidence, in order to develop and test a system which can handle chemical, biological, radiological/nuclear or explosive (CBRNe) events autonomously. This allows us to build and validate AIbased technologies, which can be trained and tested in our custom virtual environment before being deployed in real-world scenarios. We have used our virtual scenario to rapidly prototype a system which can use simulated Remote Aerial Vehicles (RAVs) to gather images from the environment for the purpose of mapping. Our environment provides us with an effective medium through which we can develop and test various AI methodologies for critical incident scene assessment, in a safe and controlled manner.
Theoretical Foundations of the A2RD Project: Part I
Braga, Juliao, Silva, Joao Nuno, Endo, Patricia Takako, Omar, Nizam
In [24], the proposal for an inter-agent communication language (ACL) that gave rise to Java Agent Development Framework (JADE), whose best-known original document is [25] followed by a complementary article [26] and a much more complete text in [27]. The importance of the environment, in which the agents interact, is characterized in a very lucid manner in [28]. All active FIPA specifications are listed in Table I.
The Disparate Effects of Strategic Manipulation
Hu, Lily, Immorlica, Nicole, Vaughan, Jennifer Wortman
When consequential decisions are informed by algorithmic input, individuals may feel compelled to alter their behavior in order to gain a system's approval. Previous models of agent responsiveness, termed "strategic manipulation," have analyzed the interaction between a learner and agents in a world where all agents are equally able to manipulate their features in an attempt to "trick" a published classifier. In cases of real world classification, however, an agent's ability to adapt to an algorithm, is not simply a function of her personal interest in receiving a positive classification, but is bound up in a complex web of social factors that affect her ability to pursue certain action responses. In this paper, we adapt models of strategic manipulation to better capture dynamics that may arise in a setting of social inequality wherein candidate groups face different costs to manipulation. We find that whenever one group's costs are higher than the other's, the learner's equilibrium strategy exhibits an inequality-reinforcing phenomenon wherein the learner erroneously admits some members of the advantaged group, while erroneously excluding some members of the disadvantaged group. We also consider the effects of potential interventions in which a learner can subsidize members of the disadvantaged group, lowering their costs in order to improve her own classification performance. Here we encounter a paradoxical result: there exist cases in which providing a subsidy improves only the learner's utility while actually making both candidate groups worse-off--even the group receiving the subsidy. Our results reveal the potentially adverse social ramifications of deploying tools that attempt to evaluate an individual's "quality" when agents' capacities to adaptively respond differ.
MARL-FWC: Optimal Coordination of Freeway Traffic Control Measures
Fares, Ahmed, Gomaa, Walid, Khamis, Mohamed A.
The objective of this article is to optimize the overall traffic flow on freeways using multiple ramp metering controls plus its complementary Dynamic Speed Limits (DSLs). An optimal freeway operation can be reached when minimizing the difference between the freeway density and the critical ratio for maximum traffic flow. In this article, a Multi-Agent Reinforcement Learning for Freeways Control (MARL-FWC) system for ramps metering and DSLs is proposed. MARL-FWC introduces a new microscopic framework at the network level based on collaborative Markov Decision Process modeling (Markov game) and an associated cooperative Q-learning algorithm. The technique incorporates payoff propagation (Max-Plus algorithm) under the coordination graphs framework, particularly suited for optimal control purposes. MARL-FWC provides three control designs: fully independent, fully distributed, and centralized; suited for different network architectures. MARL-FWC was extensively tested in order to assess the proposed model of the joint payoff, as well as the global payoff. Experiments are conducted with heavy traffic flow under the renowned VISSIM traffic simulator to evaluate MARL-FWC. The experimental results show a significant decrease in the total travel time and an increase in the average speed (when compared with the base case) while maintaining an optimal traffic flow.
Behavior Trees as a Representation for Medical Procedures
Hannaford, Blake, Bly, Randall, Humphreys, Ian, Whipple, Mark
Objective: Effective collaboration between machines and clinicians requires flexible data structures to represent medical processes and clinical practice guidelines. Such a data structure could enable effective turn-taking between human and automated components of a complex treatment, accurate on-line monitoring of clinical treatments (for example to detect medical errors), or automated treatment systems (such as future medical robots) whose overall treatment plan is understandable and auditable by human experts. Materials and Methods: Behavior trees (BTs) emerged from video game development as a graphical language for modeling intelligent agent behavior. BTs have several properties which are attractive for modeling medical procedures including human-readability, authoring tools, and composability. Results: This paper will illustrate construction of BTs for exemplary medical procedures and clinical protocols. Discussion and Conclusion: Behavior Trees thus form a useful, and human authorable/readable bridge between clinical practice guidelines and AI systems.
Proof of Reputation as Liquid Democracy for Blockchain -- Steemit
The reliable way of achieving consensus in blockchain is critical part for design of any system intended to support transparent and reliable financial ecosystem, unbiased content management and communication systems or trustable and efficient shared data storage - in all cases cheap, fast and secure at the same time. In the following, we will briefly discuss problems specific to different types of consensus algorithm, indicating problems associated with them. Further, we will introduce Proof-Of-Reputation (POR) idea and follow up with different variations and parameters of the algorithm and discuss possible architectures of its implementation. The key of the blockchain is its ability to solve so called "Byzantine General's Problem" of distributed coordination of multiple agents, with some of the agents being potentially unreliable or even alien. If probability of all agents in the system to be responsible for new block formation is the same, and there may be up to M unreliable or alien agents in the network, it is required to have at least 2*M 1 reliable and loyal agents.
FinBrain: When Finance Meets AI 2.0
Zheng, Xiaolin, Zhu, Mengying, Li, Qibing, Chen, Chaochao, Tan, Yanchao
Artificial intelligence (AI) is the core technology of technological revolution and industrial transformation. As one of the new intelligent needs in the AI 2.0 era, financial intelligence has elicited much attention from the academia and industry. In our current dynamic capital market, financial intelligence demonstrates a fast and accurate machine learning capability to handle complex data and has gradually acquired the potential to become a "financial brain". In this work, we survey existing studies on financial intelligence. First, we describe the concept of financial intelligence and elaborate on its position in the financial technology field. Second, we introduce the development of financial intelligence and review state-of-the-art techniques in wealth management, risk management, financial security, financial consulting, and blockchain. Finally, we propose a research framework called FinBrain and summarize four open issues, namely, explainable financial agents and causality, perception and prediction under uncertainty, risk-sensitive and robust decision making, and multi-agent game and mechanism design. We believe that these research directions can lay the foundation for the development of AI 2.0 in the finance field.
How chatbots are coming for our call centre jobs
The biggest threat to jobs might not be physical robots, but intelligent software agents that can understand our questions and speak to us, integrating seamlessly with all the other programs we use at home and at work. And call centres are particularly at risk. Last week we learned that British retail giant Marks & Spencer is moving 100 switchboard staff to other roles because chatbots are taking over their duties. "All calls to 640 M&S stores and contact centres now handled via Twilio-powered technology," boasted the California-based tech company operating the new system. M&S is now using Twilio's speech recognition software and Google's Dialogflow artificial intelligence (AI) tool to transcribe customers' verbal requests and understand their intent.