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Data-gov Wiki: Towards Linking Government Data

AAAI Conferences

Data.gov is a website that provides US Government data to the general public to ensure better accountability and transparency. Our recent work on the Data-gov Wiki, which attempts to integrate the datasets published at Data.gov into the Linking Open Data (LOD) cloud (yielding "linked government data"), has produced 5 billion triples – covering a range of topics including: government spending, environmental records, and statistics on the cost and usage of public services. In this paper, we investigate the role of Semantic Web technologies in converting, enhancing and using linked government data. In particular, we show how government data can be (i) inter-linked by sharing the same terms and URIs, (ii) linked to existing data sources ranging from the LOD cloud (e.g. DBpedia) to the conventional web (e.g. the New York Times), and (iii) cross-linked by their knowledge provenance (which captures, among other things, derivation and revision histories).


C-Link: Concept Linkage in Knowledge Repositories

AAAI Conferences

When searching a knowledge repository such as Wikipedia or the Internet, the user doesn’t always know what they are looking for. Indeed, it is often the case that a user wishes to find information about a concept that was completely unknown to them prior to the search. In this paper we describe C-Link, which provides the user with a method for searching for unknown concepts which lie between two known concepts. C-Link does this by modeling the knowledge repository as a weighted, directed graph where nodes are concepts and arc weights give the degree of “relatedness” between concepts. An experimental study was undertaken with 59 participants to investigate the performance of C-Link compared to standard search approaches. Statistical analysis of the results shows great potential for C-Link as a search tool.


A Formal Model of Queries on Interlinked RDF Graphs

AAAI Conferences

In this paper, we propose a model of the web of data as a graph of interlinked graphs which goes beyond the standard single-graph RDF semantics, describe two different ways in which a query on this structure can be answered, and characterize semantically each of these ways in terms of restrictions on the relation between the domain of interpretation of each single component graph.


An Ontology of Socio-Cultural Time Expressions

AAAI Conferences

Time is a concept that highly depends on the socio-cultural context. Its perception by humans is primarily based on the cultures, nations and social environment they belong to. Hence, different socio-cultural contexts imply different understandings of time. This leads to communication problems when their members start interacting with each other. In a dynamic and multi-cultural environment like today’s Web, where both billions of people with different socio-cultural contexts and numerous context dependent software applications interact, similar communication and inter-operability problems are expected. Expressing socio-cultural temporal information in an unambiguous, explicit and machine processable way can, however, help reduce such communication conflicts. In this way, heterogeneous temporal Web application systems can share the same concept of time. In this paper we present an ontology of socio-cultural time expressions that attempts to formalize the notion of socio-cultural time. The resulting model can then be used in a Web based temporal applications such as automated appointment scheduling services or calendars to provide more context sensitive service to its users.


The Immediate Present Train Model Time Production and Representation for Cognitive Agents

AAAI Conferences

Time perception and inferences there from are of critical importance to many autonomous agents. But time is not perceived directly by any sensory organ. We argue that time is constructed by cognitive processes. Here we present a model for time perception that concentrates on succession and duration, and that generates these concepts and others, such as continuity, immediate present duration, and lengths of time. These concepts are grounded through the perceptual process itself. The LIDA cognitive model is used to illustrate these ideas.


Separating Moving Objects from Landmarks

AAAI Conferences

Navigation and localization are still one of the most fundamental tasks to be accomplished by mobile autonomous robots. One of the main purposes of the navigation and localization process is to build a precise, usually allocentric spatial static representation (e.g. [S. Thrun and Schulz, 2000] ). Although robots are able to carry more and more powerful sensors, the question is, which informations are needed for localization and navigation. One way to do these tasks with only a minimal amount of resources is via landmarks. Furthermore it is an easy and failsafe way to do so. Localization can be done with only a single 180 degree camera, and a navigation by the change of the landmark ordering is very robust against misinterpretations and errors. This technique uses the fact that, seen from the agent, landmarks are switching locations only in a certain way( [Wagner, Visser, and Herzog, 2004] ). With an additional timer the robustness of this technique can be further increased. But with timing and the use of angles between the landmarks, it is also possible to measure the distances between the landmarks and the agent. Furthermore this technique can be extended to detect moving objects and to compute the speed and direction of them.


Grounding Communication Without Prior Structure

AAAI Conferences

This work describes an approach to time-series modeling of social interactions between human and robot, which is motivated by the social psychology concept of social grounding. In this model, the goal of the agents is to establish and use patterns of communication, rather than rely on existing patterns. Our goal is to allow an artifical agent to construct a pattern of shared meaning with a human or other agent through shared experience rather than relying a model provided A priori. We describe a preliminary human robot interaction study which illustrates the proposed approach.


What Can Actors Teach Robots About Interaction?

AAAI Conferences

In this paper, we describe our initial experiences using a mobile robot as a teaching aid in a stage movement class, taught in the Performing Arts Department of Washington University in St. Louis. The robot participated in a number of exercises, intended to teach the fundamentals of movement, and interacted closely with human acting students. We describe these exercises, what they are designed to teach the students, and discuss how using a robot as a teaching aid can enhance the students' experience. We describe two classes in which a robot participated, one under tele-operation and one fully autonomously, and discuss both the students' reaction to the robots, and our subjective evaluations of the systems success.


As Time Goes By: Representing and Reasoning About Timing in Human-Robot Interaction Studies

AAAI Conferences

We summarise the experimental design issues related to timing in several human-robot interaction scenarios investigating turn-taking or synchronization between child-sized humanoid robots and human participants. Our aim is not to have the humanoid robots just replicate the human’s behaviours (e.g. waving, peek-a-boo, or drumming), but to engage in interactions in a socially appropriate manner. From these various studies, we have identified several ways in which time has an impact on interaction. We have also identified practical concerns about data collection for time-dependent interactions and ways to address them. The conclusions drawn from this work is likely to be useful in informing the design of systems which engage in synchronized or turn-taking interactions with people.


Privacy and Transparency

AAAI Conferences

In this essay I argue that it is logically and practically possible to secure the right to privacy under conditions of increasing social transparency. The argument is predicated on a particular analysis of the right to privacy as the right to the personal space required for the exercise of practical rationality. It also rests on the distinction between the unidirectional transparency required by repressive governments and the increasing omnidirectional transparency that liberal information societies are experiencing today. I claim that a properly administered omnidirectional transparency will not only enhance privacy and autonomy, but can also be a key development in the creation of a society that is more tolerant of harmless diversity and temperate in its punishment of anti-social behaviors.