Direct Manipulation-like Tools for Designing Intelligent Virtual Agents

If intelligent virtual agents are to become widely adopted it is vital that they can be designed using the user friendly graphical tools that are used in other areas of graphics. However, extending this sort of tool to autonomous, interactive behaviour, an area with more in common with artificial intelligence, is not trivial. This paper discusses the issues involved in creating user-friendly design tools for IVAs and proposes an extension of the direct manipulation methodology to IVAs. It also presents an initial implementation of this methodology

Integrating internal behavioural models with external expression

Users will believe in a virtual character more if they can empathise with it and understand what ‘makes it tick’. This will be helped by making the motivations of the character, and other processes that go towards creating its behaviour, clear to the user. This paper proposes that this can be achieved by linking the behavioural or cognitive system of the character to expressive behaviour. This idea is discussed in general and then demonstrated with an implementation that links a simulation of perception to the animation of a character’s eyes

Paradata and Bayesian networks: a tool for monitoring and troubleshooting the data production process

The problem of monitoring and managing the data production process by means of process flow indicators is presented in a decision theory framework. Here it is shown how to represent and solve the decision problem via influence diagrams, i.e. Bayesian network supporting decisions. An illustrative example is provided.Expected utility, graphical models, probability update,

Affective interactions between expressive characters

When people meet in virtual worlds they are represented by computer animated characters that lack a variety of expression and can seem stiff and robotic. By comparison human bodies are highly expressive; a casual observation of a group of people mil reveals a large diversity of behavior, different postures, gestures and complex patterns of eye gaze. In order to make computer mediated communication between people more like real face-to-face communication, it is necessary to add an affective dimension. This paper presents Demeanour, an affective semi-autonomous system for the generation of realistic body language in avatars. Users control their avatars that in turn interact autonomously with other avatars to produce expressive behaviour. This allows people to have affectively rich interactions via their avatars

Model assisted approaches to complex survey sampling from finite populations using Bayesian Networks

A class of estimators based on the dependency structure of a multivariate variable of interest and the survey design is defined. The dependency structure is the one described by the Bayesian networks. This class allows ratio type estimators as a subclass identified by a particular dependency structure. It will be shown by a Monte Carlo simulation how the adoption of the estimator corresponding to the population structure is more efficient than the others. It will also be underlined how this class adapts to the problem of integration of information from two surveys through probability updating system of the Bayesian networks.Graphical models, probability update, survey design

Arran pitchstone (Scottish volcanic glass: new dating evidence

YesIn the present paper, the author offers new absolute and contextual dating evidence for Scottish archaeological pitchstone. Much archaeological pitchstone from the Scottish mainland is recovered from unsealed contexts of multi-period or palimpsest sites, and pitchstone artefacts from radiocarbon-dated pits therefore provide important dating evidence for this material group and its associated exchange network. In Scotland, all archaeological pitchstone derives from outcrops on the Isle of Arran, in the Firth of Clyde, and on the source island pitchstone-bearing assemblages include diagnostic types from the Mesolithic, Neolithic and Early Bronze Age period. Off Arran, pitchstone-bearing assemblages never include Mesolithic types, such as microliths, suggesting a post Mesolithic date. This suggestion is supported by worked pitchstone from radiocarbon-dated pits, where all presently available dates indicate that, on the Scottish mainland, Arran pitchstone was traded and used after the Mesolithic period, and in particular during the Early Neolithic period

Autonomous Secondary Gaze Behaviours

In this paper we describe secondary behaviour, this is behaviour that is generated autonomously for an avatar. The user will control various aspects of the avatars behaviour but a truly expressive avatar must produce more complex behaviour than a user could specify in real time. Secondary behaviour provides some of this expressive behaviour autonomously. However, though it is produced autonomously it must produce behaviour that is appropriate to the actions that the user is controlling (the primary behaviour) and it must produce behaviour that corresponds to what the user wants. We describe an architecture which achieves these to aims by tagging the primary behaviour with messages to be sent to the secondary behaviour and by allowing the user to design various aspects of the secondary behaviour before starting to use the avatar. We have implemented this general architecture in a system which adds gaze behaviour to user designed actions

Increasing proliferation resistance of sodium fast reactor fuel cycle through use of a nuclear resonance fluorescence detector

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, June 2010."June 2010." Cataloged from PDF version of thesis.Includes bibliographical references (p. 35).The proliferation resistance of a reprocessing facility can be improved by using a novel detection system that utilizes the nuclear resonance fluorescence (NRF) phenomenon to determine the isotopic composition of materials flowing through the plant. In an aqueous reprocessing facility, the waste stream was identified as a weak point for proliferation resistance. By identifying the isotopic composition of the waste stream and monitoring levels of plutonium and uranium, greater accountancy can be maintained. After the detection system was designed, a probabilistic risk assessment method was used to evaluate the added proliferation resistance afforded by the NRF detection system and the overall proliferation resistance of the reprocessing facility to a diversion of a small quantity of material from the waste stream by two individuals. The overall probability of success for a proliferator to divert materials from a reprocessing facility utilizing an NRF detection system is 8.73* 10-5. This is a decrease, from 3.39* 104 , over the probability of success for the proliferator if the NRF detection system is not present. This decrease in proliferator success probability demonstrates and increased proliferation resistance of the reprocessing facility. The NRF detection system is shown to increase the proliferation resistance of the reprocessing facility.by David Ballin Smith.S.B