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A Metric Scale for 'Abstractness' of the Word Meaning

AAAI Conferences

Web personalization involves automated content analysis of text, and modern technologies of semantic analysis of text rely on a number of scales. Among them is the abstractness of meaning, which is not captured by more traditional measures of sentiment, such as valence, arousal and dominance. The present work introduces a physics-inspired approach to constructing the abstractness scale based on databases of hypernym-hyponym relations, e.g., WordNet 3.0. The idea is to define an energy as a function of word coordinates that are distributed in one dimension, and then to find a global minimum of this energy function by relocating words in this dimension. The result is a one-dimensional distribution that assigns "abstractness" values to words. While positions of individual words on this scale are subject to noise, the entire distribution globally defines the universal semantic dimension associated with the notion of hypernym-hyponym relations, called here "abstractness".


DCON: Interoperable Context Representation for Pervasive Environments

AAAI Conferences

Efforts by the pervasive, context-aware system development community have over the years produced a wide variety of context-aware techniques and frameworks. However, a bulk of this technology tends to be strictly tied to a native system, thus largely limiting its external adoption. In addressing this limitation, we introduce an interoperable context representation format, in the form of an ontology, which models core context-aware concepts for re-use within pervasive computing environments. The DCON Context Ontology is proposed as a novel vocabulary for the representation of activity context as experienced by a user, and sensed through one or more of their devices. We demonstrate how, combined with other domain ontologies, DCON provides for richer representations of multi-level context interpretations that are integrated with other known background information about a user.


Using a Classical Forward Search to Solve Temporal Planning Problems under Uncertainty

AAAI Conferences

Planning with action concurrency under time and resources constraints and uncertainty is a challenging problem. Current approaches which rely on Markov Decision Processes and a discrete model for time and resources are limited by a blow-up of the search state-space. This paper presents a planner which is based on a classical forward search for solving this kind a problems. A continuous model is used for time and resources. The uncertainty on time is represented by continuous random variables which are organized in a dynamically generated Bayesian network. Two versions of the ActuPlan planner are presented. As a first step, ActuPlan_nc performs a forward-search in an augmented state-space to generate epsilon-optimal nonconditional plans which are robust to uncertainty (threshold on the probability of success). ActuPlan_nc is then adapted to generate a set of nonconditional plans which are characterized by different trade-offs between their probability of success and their expected cost. ActuPlan, the second version, builds a conditional plan with a lower expected cost by merging previously generated nonconditional plans. The branches are built by conditioning on the time. Empirical experimentation on standard benchmarks demonstrates the effectiveness of the approach.


Squaring and Scripting the ESP Game

AAAI Conferences

The ESP Game tends to generate "low effort" or "surface semantics" tags. This paper presents two variations of the ESP Games called "squaring" and "scripting" that trim the ESP Game to collect "deep semantics" tags. The approaches do not require players to get used to, and for the GWAP operators to deploy, new games. First experiments point to the efficiency of squaring and scripting the ESP Game at collecting "deep semantic" tags.


Task Context for Knowledge Workers

AAAI Conferences

Knowledge workers work on many different tasks and must often switch between those tasks. In earlier work, we have shown the benefits of automatically capturing contexts for tasks for a specific category of knowledge worker, software programmers. Captured contexts facilitate task switches and reduce information overload by enabling the display of only the information relevant to the task-at-hand. In this paper, we describe the results of two studies of the use of captured contexts for a broad range of knowledge workers. The first study we describe is a field study of eight knowledge workers who used the model in their daily work for up to 25 days on tasks involving both file and web documents. We found that these knowledge workers need information to decay from their context and that our model is adequate at automatically trimming contexts. The second study is a case study of the use of contexts to support the operations of a software development company. We analyzed task contexts from hundreds of days of work from three users and found similar trends of information decaying from contexts. Results from each study also shed more light on the nature of mixed artifact task contexts.


Activity Context Aware Digital Workspaces and Consumer Playspaces: Manifesto and Architecture

AAAI Conferences

We define and propose a manifesto and an architecture for smart digital workspaces and consumer playspaces, that “know” what the user is doing (activity structure, context, goals), how are they doing it (methods), what resources are they using (allocation and discovery), when (time) and where (location, application, device) are they doing it, who are they (profile, history), what is their role (responsibility, security, privacy) and who are their collaborators (social network), all the while observing, recording this context of work and play (institutional and social tribal knowledge). These smart workspaces and playspaces to be developed in the next five years, will let the users seamlessly move between applications and devices without having to remember or copy what they did earlier (activity context transfer and exchange), proactively show them steps others took in meaningfully similar situations before (semantic task reasoning), quickly find and show them directly related information and present answers to questions based on what they mean (proactive semantic extraction and search), in the context they need it, with access to provenance, quality and derivation of information, connect them to insights of experts within the organization and beyond, helping them reason and decide faster, with greater confidence, within a framework for managing, semantically dividing, tracking and enabling distributed work. We report two examples of the application of this architecture: a patient care system in a hospital and an assisted living system.


Learning Sociocultural Knowledge via Crowdsourced Examples

AAAI Conferences

Computational systems can use sociocultural knowledge to understand human behavior and interact with humans in more natural ways. However, such systems are limited by their reliance on hand-authored sociocultural knowledge and models. We introduce an approach to automatically learn robust, script-like sociocultural knowledge from crowdsourced narratives. Crowdsourcing, the use of anonymous human workers, provides an opportunity for rapidly acquir­ing a corpus of examples of situations that are highly specialized for our purpose yet sufficiently varied, from which we can learn a versatile script. We describe a semi-automated process by which we query human workers to write natural language narrative examples of a given situation and learn the set of events that can occur and the typical even ordering.


Preface

AAAI Conferences

Pervasive, context-aware computing technologies are essential drivers of next generation applications and appliances that will profoundly impact the way we work and play, conduct research, impart education, govern ourselves and care for our health. In order to support context-aware applications and achieve multidevice interoperability, it is important to develop an effective framework and representation language(s) for capturing and representing activity and context information, reasoning about the information and moving such information across devices in a secure and efficient manner. Our intent was as follows: First, discuss and review existing and novel Activity Context Representation and Exchange Languages. Discuss results from creation of solution architectures and proposals for languages, data structures, operations to enable top use-case categories. Second, discuss papers and proposals for new research areas and review work building on key research themes with specific opportunities for collaborative work in the next two-three years in this academically and commercially important area, with topics including, but not limited to semantic computing, task modeling, context representation, and activity recognition.


A Neural-Symbolic Cognitive Agent with a Mind’s Eye

AAAI Conferences

The DARPA Mind’s Eye program seeks to develop in machines a capability that currently exists only in animals: visual intelligence. This paper describes a Neural-Symbolic Cognitive Agent that integrates neural learning, symbolic knowledge representation and temporal reasoning in a visual intelligent system that can reason about actions of entities observed in video. Results have shown that the system is able to learn and represent the underlying semantics of the actions from observation and use this for several visual intelligent tasks, like recognition, description, anomaly detection and gap-filling.


Planning the Transformation of Network Topologies

AAAI Conferences

Refining a network topology is an important network management technique. Nevertheless, determining the appropriate steps to transform a network from one topology to another, in a way that minimizes service disruptions, has received little attention. This is a critical problem since service disruptions can be particularly harmful and costly for networks hosting mission-critical services. In this paper, we introduce the incremental network transformation (INT) problem and explore this problem in the context of automated planning. We define two metrics to measure the quality of generated transformation plans, one of which is amenable to classical propositional planning. We find that while state-of-the-art domain-independent planning techniques are effective at finding high-quality solutions for small problem instances, they cannot scale to solve realistically sized INT instances. To address the shortcomings of existing approaches, we developed a number of domain-dependent planners that use novel domain-specific heuristics. We empirically evaluated our planners on a wide range of synthetic network topologies. Our results illustrate that our automated planning inspired techniques are effective on realistically sized INT problems. We envision that our approach could eventually provide a compelling addition to the arsenal of techniques employed by network practitioners to support network refinement with minimal disruption to running services.