Interactive Construction and Animation of Layered Elastically Deformable Characters

An interactive system is described for creating and animating deformable 3D characters. By using a hybrid layered model of kinematic and physics-based components together with an immersive 3D direct manipulation interface, it is possible to quickly construct characters that deform naturally when animated and whose behavior can be controlled interactively using intuitive parameters. In this layered construction technique, called the elastic surface layer model, a simulated elastically deformable skin surface is wrapped around a kinematic articulated figure. Unlike previous layered models, the skin is free to slide along the underlying surface layers constrained by geometric constraints which push the surface out and spring forces which pull the surface in to the underlying layers. By tuning the parameters of the physics-based model, a variety of surface shapes and behaviors can be obtained such as more realistic-looking skin deformation at the joints, skin sliding over muscles, and dynamic effects such as squash-and-stretch and follow-through. Since the elastic model derives all of its input forces from the underlying articulated figure, the animator may specify all of the physical properties of the character once, during the initial character design process, after which a complete animation sequence can be created using a traditional skeleton animation technique. Character construction and animation are done using a 3D user interface based on two-handed manipulation registered with head-tracked stereo viewing. In our configuration, a six degree-of-freedom head-tracker and CrystalEyes shutter glasses are used to display stereo images on a workstation monitor that dynamically follow the user head motion. 3D virtual objects can be made to appear at a fixed location in physical space which the user may view from different angles by moving his head. To construct 3D animated characters, the user interacts with the simulated environment using both hands simultaneously: the left hand, controlling a Spaceball, is used for 3D navigation and object movement, while the right hand, holding a 3D mouse, is used to manipulate through a virtual tool metaphor the objects appearing in front of the screen. Hand-eye coordination is made possible by registering virtual space to physical space, allowing a variety of complex 3D tasks necessary for constructing 3D animated characters to be performed more easily and more rapidly than is possible using traditional interactive techniques.     

PMO managers' self-determined participation in a purposeful virtual community-of-practice

Communities-of-practice (CoPs) have received significant attention within a variety of literatures but we remain largely ignorant of the potential of purposefully-created CoPs in global organisations. In this context, the challenge is likely to be convincing ‘masters’ (Wenger, 1998) on the merits of joining the conversation on practice at a distance, thus making the willingness for exchange a key to the quality and longevity of the community. We posed the question “Why would busy, dispersed, knowledgeable professionals want to join and participate in a deliberately-organised CoP?” Our 2-year collaborative action study allowed us to observe the CoP and its membership at close range. We conclude that autonomy, competence and belonging underscore participation, co-production and diffusion of innovative problem-solving and practice beyond the CoP. The study will inform organisations contemplating similar interventions and also serves as a basis for further investigation and theory building on organized CoPs by the research community.     

Three-dimensional distinct element modelling and dynamic runout analysis of a landslide in gneissic rock, British Columbia, Canada

The McAuley Creek Landslide is a 6?million m³ gneissic rock slope failure that occurred in British Columbia (Canada) in late May–early June 2002. The geological strength index was used to characterize the quality of the overall rock mass and its reduced (damaged) quality near tectonic structures and alteration zones. Potential slope failure mechanisms were investigated using four analysis techniques including: kinematic analysis, surface wedge limit equilibrium (combination) analysis, block theory and three-dimensional distinct element models. Results from all four analyses suggested that the dominant slope failure mechanism was wedge sliding along the intersection of the gneissic foliation and a steeply dipping discontinuity set striking perpendicular to the slope. Of the 6?million m³ of material involved in the landslide, an estimated 5 million?m³ was deposited immediately below the source area against the opposite valley wall, with the remaining 1 million m³ travelling an additional 1.6?km downstream. The runout behaviour was investigated using a three-dimensional dynamic analysis code.     

Forecast aggregation via recalibration

It is known that the average of many forecasts about a future event tends to outperform the individual assessments. With the goal of further improving forecast performance, this paper develops and compares a number of models for calibrating and aggregating forecasts that exploit the well-known fact that individuals exhibit systematic biases during judgment and elicitation. All of the models recalibrate judgments or mean judgments via a two-parameter calibration function, and differ in terms of whether (1) the calibration function is applied before or after the averaging, (2) averaging is done in probability or log-odds space, and (3) individual differences are captured via hierarchical modeling. Of the non-hierarchical models, the one that first recalibrates the individual judgments and then averages them in log-odds is the best relative to simple averaging, with 26.7 % improvement in Brier score and better performance on 86 % of the individual problems. The hierarchical version of this model does slightly better in terms of mean Brier score (28.2 %) and slightly worse in terms of individual problems (85 %).     

Facile Synthesis and Proposed Mechanism of α,ω‐Oxetanyl-Telechelic Poly(3-nitratomethyl-3-methyl oxetane) by an SN2(i) Nitrato Displacement Method in Basic Media

The synthesis of a novel heterocyclic–telechelic polymer, α,ω-oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane), is described. Infrared spectroscopy (IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy have been used to confirm the successful synthesis, demonstrating the presence of the telechelic-oxetanyl moieties. Synthesis of the terminal functionalities has been achieved via displacement of nitrato groups, in a manner similar to that employed with other leaving groups such as azido, bromo, and nitro, initiated by nucleophiles. In the present case, displacement occurs on the ends of a nitrato-functionalized polymer driven by the formation of sodium nitrate, which is supported by the polar aprotic solvent N,N-dimethyl formamide. The formation of an alkoxide at the polymer chain ends is favored and allows internal back-biting to the nearest carbon bearing the nitrato group, intrinsically in an S_N2(i) reaction, leading to α,ω-oxetanyl functionalization. The telechelic-oxetanyl moieties have the potential to be cross-linked by chemical (e.g., acidic) or radiative (e.g., ultraviolet) curing methods without the use of high temperatures, usually below 100°C. This type of material was designed for future use as a contraband simulant, whereby it would form the predominant constituent of elastomeric composites comprising rubbery polymer with small quantities of solids, typically crystals of contraband substances, such as explosives or narcotics. This method also provides an alternative approach to ring closure and synthesis of heterocycles.     

Cultivating the Herb Garden of Scandinavian Mathematics: The Congresses of Scandinavian Mathematicians, 1909–1925

As a reaction to the changed political landscape in Scandinavia following the dissolution of the union between Norway and Sweden in 1905, the prominent Swedish mathematician Gösta Mittag‐Leffler extended ‘a brotherly hand,’ calling for Scandinavian colleagues to meet for a congress of mathematicians in Stockholm in 1909. This event became the first in a series of biannual meetings which proved to be an important institution for Scandinavian mathematics. During the first decades after 1909, the congresses would form and consolidate themselves through the construction of a new Scandinavian identity for mathematicians which developed alongside and in relation to both international and national contexts and developments. In this paper, we shall demonstrate that these meetings served a complex set of agendas at the individual, national, and international level. In particular, they reflect a changing conception of cooperation in science for mutual cultural gain combined with a flexible institutionalisation that allowed the Scandinavian mathematicians to use the congresses for various diplomatic ambitions. We base our analyses of the Scandinavian Congresses of Mathematics on the notion of a shared ‘conational’ identity developed adjacent to national identities. We then analyse the formation, consolidation, delineation, and reflections of this institution in order to demonstrate how the efforts to unite Scandinavian mathematicians were contingent on and influenced by simultaneous currents of internationalisation and shared history, culture, and language in the Scandinavian region.     

Bacteria in a water‐damaged building: associations of actinomycetes and non‐tuberculous mycobacteria with respiratory health in occupants

We examined microbial correlates of health outcomes in building occupants with a sarcoidosis cluster and excess asthma. We offered employees a questionnaire and pulmonary function testing and collected floor dust and liquid/sludge from drain tubing traps of heat pumps that were analyzed for various microbial agents. Forty‐nine percent of participants reported any symptom reflecting possible granulomatous disease (shortness of breath on exertion, flu‐like achiness, or fever and chills) weekly in the last 4 weeks. In multivariate regressions, thermophilic actinomycetes (median = 529 CFU/m²) in dust were associated with FEV₁/FVC [coefficient = ?2.8 per interquartile range change, P = 0.02], percent predicted FEF_25–75% (coefficient = ?12.9, P = 0.01), and any granulomatous disease‐like symptom [odds ratio (OR) = 3.1, 95% confidence interval (CI) = 1.45?6.73]. Mycobacteria (median = 658 CFU/m²) were positively associated with asthma symptoms (OR = 1.5, 95% CI = 0.97?2.43). Composite score (median = 11.5) of total bacteria from heat pumps was negatively associated with asthma (0.8, 0.71?1.00) and positively associated with FEV₁/FVC (coefficient = 0.44, P = 0.095). Endotoxin (median score = 12.0) was negatively associated with two or more granulomatous disease‐like symptoms (OR = 0.8, 95% CI = 0.67?0.98) and asthma (0.8, 0.67?0.96). Fungi or (1→3)‐β‐D‐glucan in dust or heat pump traps was not associated with any health outcomes. Thermophilic actinomycetes and non‐tuberculous mycobacteria may have played a role in the occupants' respiratory outcomes in this water‐damaged building.     

Determining optimum flash patterns for emergency service vehicles: An experimental investigation using high definition film

An investigation of how emergency vehicle lighting (EVL) can be improved is reported with reference to an analysis of police vehicle road traffic accidents (Study 1). In Study 2, 37 regular drivers were shown film clips of a marked police vehicle, in which flash rate (1 Hz, 4 Hz) and pattern (single, triple pulse) were varied on the blue Light Emitting Diode (LED) roofbar. Results indicate a 4 Hz flash rate conveys greater urgency than a 1 Hz rate, while a 1 Hz, single flash combination was ranked the least urgent of all combinations. Participants claimed they would leave significantly more space before pulling out in front of an approaching police car (gap acceptance) in the 4 Hz single pulse condition in comparison to other EVL combinations. The preliminary implications for which flash characteristics could prove most optimal for emergency service use are discussed with regard to effects on driver perception and expected driving behaviour.     

The management of the project-based organization: A personal reflection

In this paper I make a personal reflection on my research and writings in the field of Project Management over the past 30 years. My research has primarily been about the management of the project-based organization. Within that I have researched governance, organizational behaviour, contingency, marketing, success and shareholder value.