Vehicle-sharing (ex: bike sharing, car sharing) is widelyadopted in many cities of the world due to concernsassociated with extensive private vehicle usage, whichhas led to increased carbon emissions, traffic conges-tion and usage of non-renewable resources. In vehicle-sharing systems, base stations are strategically placedthroughout a city and each of the base stations containa pre-determined number of vehicles at the beginningof each day. Due to the stochastic and individualisticmovement of customers, typically, there is either con-gestion (more than required) or starvation (fewer thanrequired) of vehicles at certain base stations. As demon-strated in our experimental results, this happens oftenand can cause a significant loss in demand. We proposeto dynamically redeploy idle vehicles using carriers soas to minimize lost demand or alternatively maximizerevenue of the vehicle sharing company. To that end,we contribute an optimization formulation to jointly ad-dress the redeployment (of vehicles) and routing (of car-riers) problems and provide two approaches that rely ondecomposability and abstraction of problem domains toreduce the computation time significantly. Finally, wedemonstrate the utility of our approaches on two realworld data sets of bike-sharing companies.

Skills are generally designed by a domain expert, but designing a `good' set of skills can be challenging in high-dimensional, complex domains. In some cases, the skills may contain useful prior knowledge but cannot solve the task, resulting in a sub-optimal solution or no solution at all. Given a `poor' set of skills, we would like to dynamically improve them. The main contribution of this paper is showing that Interrupting Options (IO) can improve the initial skill set in a high-dimensional, complex domain by learning when to switch between skills. Furthermore, we discuss some of the pitfalls we ran into while trying to get IO to work.

We are concerned with controlling dynamical systems, such as self-driving cars and smart buildings, in a manner that guarantees that they satisfy complex task specifications. Mixed integer linear programming has recently proven to be a powerful tool for such problems, enabling the computation of optimal plans that satisfy complex temporal constraints for high-dimensional, dynamical systems. These optimization-based approaches find solutions quickly for challenging (and previously unsolvable) planning problems. Framing temporal logic planning as constrained optimization also presents exciting new areas of research.

We built a conversational agent performing social promotion (CASP) to assist in automation of interacting with Facebook friends. CASP relies on a domain-independent natural language relevance technique which filters web mining results to support a conversation with friends and other network members. In this study we focus on recognizing friends’ intents to better support automated conversation with them. We learn the plausible sequences of communicative actions and mental states as they are expressed in text to support plausible dialogue. We evaluate the relevance of the constructed conversations with respect to suitability of topicality and communicative actions, measuring how human users loose trust in the system. It is confirmed that maintaining a plausible sequences of communicative actions in automated postings is important for retaining trust of human peers and efficient social promotion by means of CASP.

This paper is concerned with extension of AngledCORE-9 by Sokeh, Gould, and Renz, a comprehensive representation of spatial information that can be efficiently extracted from interacting objects present in video using their approximated bounding box. Spatial information is important for identification of relation between multiple objects, hence the work is a step forward for tasks such as semantics content analysis and visual information access. To that end we present an approach to incorporating the spatiotemporal volume of objects into AngledCORE-9. The approach is able to detect, track and segment object volumes from a video stream, based on which spatial information is identified in an efficient manner. Accurate spatial and temporal information can be obtained by precise representation of the shape region and the oriented bounding box. A human action classification task is adopted in order to assess the performance of the approach. The experiment with two challenging datasets indicates that the outcome of this approach is comparable to the state-of-the-art.

Sophisticated autonomous AI may need to base its behavior on fuzzy concepts such as well-being or rights. These concepts cannot be given an explicit formal definition, but obtaining desired behavior still requires a way to instill the concepts in an AI system. To solve the problem, we review evidence suggesting that the human brain generates its concepts using a relatively limited set of rules and mechanisms. This suggests that it might be feasible to build AI systems that use similar criteria for generating their own concepts, and could thus learn similar concepts as humans do. Major challenges to this approach include the embodied nature of human thought, evolutionary vestiges in cognition, the social nature of concepts, and the need to compare conceptual representations between humans and AI systems.

This article discusses the notion of context transfer in reinforcement learning tasks. Context transfer, as defined in this article, implies knowledge transfer between tasks that share the same environment's dynamics and reward function, but have different state and action spaces. For example, we have a working mobile robot in an environment. At some point, we decide to upgrade its sensors and/or actuators. Any change in these modules will result in a different description of the agent-environment model, and the trained knowledge is no longer applicable. We consider the tasks of the old and new robots, as the source and target tasks, respectively. The Markov decision process (MDP) of these tasks, under certain conditions, are called Q-transferable tasks, and the problem of knowledge transfer between them is called context transfer. We investigate the relation of the MDPs of these tasks.

In this paper, we exploit Bayesian nonparametric microphone array processing (BNP-MAP) for analyzing the spatio-temporal patterns of the frog chorus. Such analysis in real environments is made more difficult due to unpredictable sound sources including calls of various species of animals. An application of conventional signal processing algorithms has been difficult because these algorithms usually require the number of sound sources in advance. BNP-MAP is developed to cope with auditory uncertainties such as reverberation or unknown number of sounds by using a unified model based on Bayesian nonparametrics. We exploit BNP-MAP for analyzing the sound data of 20 minutes captured by a 7-channel microphone array in a paddy rice field in Oki Island, Japan, and revealed that two individuals of Schlegel's green tree frog (Rhacophorus schlegelii) called alternately with anti-phase. This result is compared with the video data captured by a video camera with 18 units of sound-imaging devices called Firefly deployed along the bank of the rice field. The auditory result provides more detailed patterns of the frog chorus in higher temporal resolutions. This higher resolution enables to analyze fine temporal structures of the frog calls. For example, BNP-MAP reveals the trill-like calling pattern of R. schlegelii.

We analyze the results of assistance to individuals with autism in reasoning about mental world. This assistance is provided by a natural language multiagent simulator of mental states, NL_MAMS (Galitsky 2013b). It assists in the tasks which are the hardest for autistic reasoning: operating with mental states and actions. Autistic patients are trained to perform a number of reasoning exercises. We conduct both short term and long term evaluations including the behavior in real world and confirm that the system has a positive effect on their rehabilitation.

One approach to conserving endangered species is to purchase and protect a set of land parcels in a way that maximizes the expected future population spread. Unfortunately, an ideal set of parcels may have a cost that is beyond the immediate budget constraints and must thus be purchased incrementally. This raises the challenge of deciding how to schedule the parcel purchases in a way that maximizes the flexibility of budget usage while keeping population spread loss in control. In this paper, we introduce a formulation of this scheduling problem that does not rely on knowing the future budgets of an organization. In particular, we consider scheduling purchases in a way that achieves a population spread no less than desired but delays purchases as long as possible. Such schedules offer conservation planners maximum flexibility and use available budgets in the most efficient way. We develop the problem formally as a stochastic optimization problem over a network cascade model describing a commonly used model of population spread. Our solution approach is based on reducing the stochastic problem to a novel variant of the directed Steiner tree problem, which we call the set-weighted directed Steiner graph problem. We show that this problem is computationally hard, motivating the development of a primal-dual algorithm for the problem that computes both a feasible solution and a bound on the quality of an optimal solution. We evaluate the approach on both real and synthetic conservation data with a standard population spread model. The algorithm is shown to produce near optimal results and is much more scalable than more generic off-the-shelf optimizers. Finally, we evaluate a variant of the algorithm to explore the trade-offs between budget savings and population growth.