While mobile authoring applications are proliferating, choreographic tools that support the generation and transformation of user-created movement `samples' are less readily available. iDanceForms is a novel mobile choreographic application that generates unique movement choices through a camera stillframing technique to provoke movement catalysts. In keeping with the principles of whole body interaction (and principles of `defamiliarization'), the design of iDanceForms supports opportunities for surprise, unexpected movement choices and meaning-making. This paper presents data collected from an observational study of choreographers using iDanceForms. In the study we found that choreographers appropriated the intended functionality of iDanceForms to create highly individualized and unexpected movement sequences. They found inspiration in exploring unexpected framing of form and content, which resulted in creative explorations that produced unique movement possibilities provided by the system. Drawing from our observations we discuss possible roles that sensor-enabled mobile devices could play in movement generation through personal meaning-making, creative choreographic strategies and discovery, and in provoking whole body interaction through principles of `defamiliarization' in the context of HCI.

Abstract This paper presents a social agent pedestrian model based on experiments with human subjects. Research studies of criminology and environmental psychology show that certain features of the urban environment generate fear in people, causing them to take alternate routes. The Crime Prevention Through Environmental Design (CPTED) strategy has been implemented to reduce fear of crime and crime itself. Our initial prototype of a pedestrian model was developed based on these findings of criminology research. In the course of validating our model, we constructed a virtual environment (VE) that resembles a well‐known fear‐generating area where several decision points were set up. 60 human subjects were invited to navigate the VE and their choices of routes and comments during the post interviews were analyzed using statistical techniques and content analysis. Through our experimental results, we gained new insights into pedestrians' behavior and suggest a new enhanced and articulated agent model of a pedestrian. Our research not only provides a realistic pedestrian model, but also a new methodology for criminology research. Copyright © 2008 John Wiley & Sons, Ltd.

Since the inception of the field, researchers in human figure animation have had an active interchange with those interested in representing and visualizing dance. In 1967 A. Michael Noll at Bell Labs and Merce Cunningham, the father of modern dance speculated independently about the possibility of creating dancing stick figures on a computer display.

Emerging technologies offer exciting new ways of using entertainment technology to create fantastic play experiences and foster interactions between players. Evaluating entertainment technology is challenging because success isn't defined in terms of productivity and performance, but in terms of enjoyment and interaction. Current subjective methods of evaluating entertainment technology aren't sufficiently robust. This paper describes two experiments designed to test the efficacy of physiological measures as evaluators of user experience with entertainment technologies. We found evidence that there is a different physiological response in the body when playing against a computer versus playing against a friend. These physiological results are mirrored in the subjective reports provided by the participants. In addition, we provide guidelines for collecting physiological data for user experience analysis, which were informed by our empirical investigations. This research provides an initial step towards using physiological responses to objectively evaluate a user's experience with entertainment technology.

Effects of self-regulated learning (SRL) have been investigated in a variety of contexts. In this research, we explore advanced learning technologies based on the information processing model of SRL in the context of structured programming. We conducted an experiment to study ways to enhance the use of programmers' working memory, to develop tactics to carry out task level activities during programming, and to learn how to program more effectively. The results of the experiment indicate that programmers who received SRL-based treatment outperformed programmers who did not receive the treatment. We argue that the infusion of SRL-based technological interfaces would have a positive influence on the performances in programming.

Abstract Symbolic systems such as Labanotation for notating dance and choreography provide a critical tool for the preservation of cultural heritage in what once was considered an ‘illiterate’ art form. While the goals of such notation systems are laudable, the unfortunate reality is that most dancers and choreographers cannot read or write the notation; that is, they are loath to take the considerable effort to learn a rich, but complex methodology. To make Labanotation scores more accessible the LabanDancer system has been developed to translate Labanotation scores recorded in the LabanWriter editor into 3‐d human figure animations. A major challenge in the development of this translator has been to find approaches that are general enough to create reasonable animations for a wide variety of different movements. Any translator must also take account of the context of a movement since this can affect the interpretation of the Labanotation scores. Copyright © 2005 John Wiley & Sons, Ltd.

CSCW is one mechanism by which the TeleLearning Exchange Project promotes collaboration in the interdisciplinary research of the TeleLearning Network of Centres of Excellence (TL-NCE). Affiliated researchers are encouraged to share informal knowledge of their projects via three major strategies: site visits by an integration officer, a community Web repository (http://teleport.techbc.ca) and collaborative visits by students. An informal goal of the TeleLearning Exchange is to scaffold the next generation of collaborative researchers by actively involving students affiliated with the TL-NCE as agents of interdisciplinary cooperation and technical integration. The paper describes the design and development issues surrounding a Web repository tool to build a community of practice.

The Virtual Hand Lab (VHL) is an an augmented reality envimnment for conducting experiments in human perception and motor performance that involve grasping, manipulation, and other 3D tasks that people perform with their hands.The hardware and software testbed supports both physical and virtual objects, and object behaviors that cm be specified in advance by experimenters.A testbed for conducting experiments must provide visual stimuli that depend on the configuration of the experimental apparatus, on the specific tasks that are being studied, and on the individual characteristics of each subject.Calibration is an important concern and is the subject of this paper.A proper design leads to independent calibration steps that modularize the subsystems that require calibration and explicitly recognize and order the dependencies among them.We describe how the architecture for the VHL was designed to support independent apparatus-specific, experiment-specific, and subject-specific calibrations.The architecture offers benefits for any augmented reality environment by reducing m-calibration times and identifying appropriate modularization in the software that can result in a more robust and efficient implementation.

High level tools to support the animation of multiple human figures make use of knowledge in a number of ways. Explicit knowledge, in the form of keyframes is supplied directly by the animator and procedural knowledge for repetitive movements like walking or grasping is built into the algorithms. However, the interaction of multiple figures in a complex environment requires a declarative knowledge base of rules and constraints. The most obvious way to add declarative knowledge to an animation system is to choose a well developed expert system and to set up communication channels between the two systems, but this "two monoliths" approach can be very inefficient. To avoid the problems associated with distinct expert and animation systems, we are implementing a blackboard architecture which allows integration of reasoning with the graphics algorithms. The result is a mixed initiative system where autonomously produced motion paths for multiple human figures are edited and constrained interactively by the animator. A partial implementation is being evaluated.>

A constraint-based reasoning system is used for knowledge representation and reasoning in behavioural animation, specifically in the animation of sailing behaviour. The object-oriented ECHIDNA reasoning and constraint logic programming shell handles the constraints for formulation and execution of plans for intelligent entities. At higher levels of control, the observed motion of an object is a reflection of the reasoning process of an intelligent entity as it reacts to its environment. The environment, internal knowledge and physical structure serve as constraints in developing a plan, which in turn provides additional constraints in the animation of reactive behaviour. An animation approach using constraint-based reasoning is presented focusing on details of the planning process adapted in the approach. The implementation of the NSAIL program reveals further insight into applying this approach towards the development of a high-level intuitive interface for behavioural animation. >

Abstract Behaviour is a reflection of a reasoning process that must deal with constraints imposed by an external environment, internal knowledge and physical structure. This paper proposes a framework for behavioural animation that is based on the next generation of object‐oriented, constraint‐based expert systems technology, and applies a control structure of knowledge agents and knowledge units to determine the behaviour of objects to be animated. Knowledge agents are responsible for planning, plan implementation and information extraction from the environment. The activity of an agent is dependent on the knowledge units ascribed to them by the animator. The interaction between agents and knowledge units is resolved by the reasoning engine, and thus, influences the eventual motion displayed. An example given is NSAIL, a pilot implementation using the model‐based ECHIDNA constraint logic programming shell. With this approach, the motion for a sailing scenario and other behavioural domains can be specified at a high level through the characterization of the knowledge agents.

This paper explores the nature of creative composition particularly as it applies to dance, and describes the development of interactive computer based tools to assist the composer. The hierarchical nature of the composition process calls for an interface which allows the composer the flexibility to move back and forth between alternate views and conceptual levels of abstraction.COMPOSE, an interactive system for the composition of dance has been implemented on Silicon Graphics and Apple workstations. The user visually composes in space and in time using menus of postures and sequences. Paths can be edited and an animation of the dance composition allows the final result to be evaluated.

This paper presents a hybrid approach to the animation of human locomotion which combines goal-directed and dynamic motion control. Knowledge about a locomotion cycle is incorporated into a hierarchical control process. The desired locomotion is conveniently specified at the top level as a task (e.g. walk at speed v), which is then decomposed by application of the concepts of step symmetry and state-phase-timings. As a result of this decomposition, the forces and torques that drive the dynamic model of the legs are determined by numerical approximation techniques. Rather than relying on a general dynamic model, the equations of motion of the legs are tailored to locomotion and analytically constrained to allow for only a specific range of movements. The dynamics of the legs produce a generic, natural locomotion pattern which is visually upgraded by some kinematic "cosmetics" derived from such principles as virtual leg and determinants of gait. A system has been implemented based on these principles and has shown that when a few parameters, such as velocity, step length and step frequency are specified, a wide variety of human walks can be generated in almost real-time.

A representation scheme is proposed for describing 3-D mechanical parts and structural bodies which are formed from planes and quadratic faces. Since the method combines features of the constructive solid geometry (CSG) representation and an extension of the enhanced (EESI) spherical image representation (ESI), it is designated the CSG-EESI. In this scheme, the body model is roughly divided into two levels: the higher level corresponds to a restricted CSG tree that contains the structural information describing how the various subparts form the body; the lower level contains the geometric information for those simple subparts and represents them by an extension of enhanced spherical images. The scheme can be used both as the medium between pictorial models and relational models and as an internal model to facilitate the recognition of bodies. An expert system written in C-PROLOG on a VAX 11/750 is presented that converts BR-like models into the CSG-EESI representation is presented.>

New single- and multiprocessor models for ray tracing are presented. Important features are (1) the use of custom VLSI building blocks, (2) the use of a modified hierarchical data-structure-based ray tracing algorithm with three disjoint data sets, and (3) scene access through adaptive information broadcasting. A modular design is presented that permits incremental performance enhancement up to two orders of magnitude over conventional minicomputers or workstations. Ray tracing is a surprisingly good application for a shared bus architecture because of the computational complexity of intersecting light rays with graphics objects.

Animation of human movement can be based either on analog inputs derived directly from actual movements or on symbolic inputs chosen to produce the desired movement. The former type of input can be quite accurate and objective but is a description of the required movement whereas the latter is often quite imprecise and subjective but provides an analysis of the required movements. Two existing systems for a computer based animation are being used to explore the problems involved in integrating such inputs. Specifically, animation driven by analog signals from electro-goniometers is integrated with animation derived from Labanotation commands; the results are illustrated with a short movie.

A systems model is proposed to relate a profile of athletic performance to a profile of training. The general model assumes that performance has four components: endurance, strength, skill, and psychological factors. Each of these factors is discussed and ascribed a transfer function. A major problem is the quantification of both training and performance. The case of a swimmer is studied in detail. It is shown that if a time series of training impulses is used as input, his performance in 100 m criterion performances can be modeled rather well with a simple linear system. The major conclusion is that performance appears to be related to the difference between fitness and fatigue functions. The fitness function is related to training by a first-order system with time constant 50 days, whereas the fatigue function is related to training by a similar system with time constant 15 days. An appendix is provided to show how these systems can be simulated on a simple electronic calculator. The relationship of these relatively short-term efects on the individual performer (six months) to longer term effects on the same indiviudal is also discussed.

Any effective model of a nontrivial portion of the nervous system cannot possibly account in detail for the activity of individual cells. We have developed an approach to modeling cortical systems by taking advantage of the regularities of the macrostructure and the stochastic nature of the spatial microstructure and temporal activity. A gross linear or nonlinear description is found for the local activity of neural tissue. If the local activity can be described by a function which is linear in space and time, then this can be convoluted with any spatiotemporal input pattern to predict the output. When applied to the cerebellar cortex this approach has resulted in a model analogous to an anisotropic spatial filter with interesting temporal properties. The model predicts that the cerebellar cortex will enhance the detail (in space and time) of any input pattern. However, the form of the spatial transfer function depends on the temporal frequency of the input and vice-versa.

Vectorcardiography is an important area of human and machine pattern recognition. The wide range of interclass variation in observed VCGs is attributed to variations in body structure. Intra-class differences can be minimized and interclass differences maximized if a linear normalization procedure is used to eliminate variations due to individual body differences.

It is known that R linearly separable classes of multidimensional pattern vectors can always be represented in a feature space of at most R dimensions. An approach is developed which can frequently be used to find a nonorthogonal transformation to project the patterns into a feature space of considerably lower dimensionality. Examples involving classification of handwritten and printed digits are used to illustrate the technique.