Interactive Multimedia Explanation for Equipment Maintenance and Repair

COMET (COordinated Multimedia Explanation Testbed) is a research system that we are developing to explore the coordinated generation of multimedia explanations of equipment maintenance and repair procedures. The form and content of all material presented is generated interactively, with an emphasis on coordinating multiple media to allow cross-references between media and to make possible display layout that reflects the fine-grain relationships among the material presented. COMET's architecture includes multiple static and dynamic knowledge sources, a content planner, a media coordinator, media generators (currently text and graphics), and a media layout manager. Examples are given of the kinds of material processed and produced by each of the components

Coordinating Text and Graphics in Explanation Generation

To generate multimedia explanations, a system must be able to coordinate the use of different media in a single explanation. In this paper, we present an architecture that we have developed for COMET (COordinated Multimedia Explanation Testbed), a system that generates directions for equipment maintenance and repair, and we show how it addresses the coordination problem. In particular, we focus on the use of a single content planner that produces a common content description used by multiple media-specific generators, a media coordinator that makes a f'me-grained division of information between media, and bidirectional interaction between media-specific generators to allow influence across media.

Development of predictable palladium based optomechanical hydrogen sensors

In addition to its use as an energy storage medium or fuel, hydrogen gas has a variety of commercial applications such as methanol and ammonia production. Given the volatility and flammability of hydrogen, as well as its small molecular size, fast and accurate sensors capable of operating in a variety of environments are necessary. A large subset of hydrogen gas sensors rely on palladium metal, which is known to reversibly react with hydrogen to form palladium hydride. This results in a change in the optical, electrical and mechanical properties of the film. These changes are a result of a change the Fermi level and band structure of the metal, as well as an increase in lattice constant in the presence of hydrogen. The change in complex refractive index plays a role in both reflection/transmission, and for determining resonances or guided modes in waveguides and other sub-wavelength features. However, the increase in the lattice constant of the metal, a process called hydrogen induced lattice expansion, was found to be equally important in modeling the response of the sensors, both from an optical and a mechanical perspective. This dissertation is concerned with the simulation, fabrication, and testing of palladium based optomechanical sensors, particularly to elucidate the role of hydrogen induced lattice expansion in their design and functionality. Two specific sensor designs: a nano-aperture based sensor and a cantilever based sensor were designed, fabricated, characterized, and modeled. The first sensor developed was based on a single nano-aperture etched into a palladium coated fiber facet. Designed to operate based on the principle of extraordinary transmission and the change in optical constants of the palladium, this sensor showed experimental sensitivity down to 150ppm in transmission and 50 ppm reflection. However, without inclusion of the mechanical effects, the device behavior was unpredictable. Separate work was thus carried out to characterize lattice expansion in thin palladium films using quantitative phase imaging techniques, so that a new sensor could be designed and accurately modelled. This second fabricated sensor consisted of a Pd coated cantilever which operated based on optical probing of mechanical deflections. For more thorough characterization, the cantilever was measured using the same phase imaging techniques. The results of this analysis further improved the understanding of thin film expansion and the capabilities of diffraction phase microscopy for material analysis. Furthermore, this culminated in the fabrication of a sensitive and reliable optomechanical hydrogen sensor whose response matched theory

Generation and Evaluation of Intraoperative Inferences for Automated Health Care Briefings on Patient Status After Bypass Surgery

The authors present a system that scans electronic records from cardiac surgery and uses inference rules to identify and classify abnormal events (e.g., hypertension) that may occur during critical surgical points (e.g., start of bypass). This vital information is used as the content of automatically generated briefings designed by MAGIC, a multimedia system that they are developing to brief intensive care unit clinicians on patient status after cardiac surgery. By recognizing patterns in the patient record, inferences concisely summarize detailed patient data

An Evaluation of Automatically Generated Briefings of Patient Status

We report on an evaluation of MAGIC, a system that automatically generates briefings of patient status after coronary bypass surgery, completed in the Cardio Thoracic Intensive Care Unit at New York Presbyterian Hospital. Through enhancements in system design, robustness and speed, we compared information obtained by nurses against two briefings, one automatically generated by MAGIC and one provided by physicians upon the patient's arrival to the ICU. Our results show that MAGIC and the physician briefing provide a substantial increase in the amount of information than is available prior to the patient's arrival and that the information MAGIC provides is accurate. In many aspects, MAGIC out-performs the physician briefing; information is reported earlier and is always available. We conclude that MAGIC provides the CT ICU staff early on with a better assessment of the patient's status than in current practice and allows them to better prepare for the patient's arrival

Generating multimedia briefings: coordinating language and illustration

AbstractCommunication can be more effective when several media (such as text, speech, or graphics) are integrated and coordinated to present information. This changes the nature of media-specific generation (e.g., language or graphics generation), which must take into account the multimedia context in which it occurs. This paper presents work on coordinating and integrating speech, text, static and animated three-dimensional graphics, and stored images, as part of several systems we have developed at Columbia University. A particular focus of our work has been on the generation of presentations that brief a user on information of interes

Observation of out-of-plane spin texture in a SrTiO3 (111) two-dimensional electron gas

We explore the second order bilinear magnetoelectric resistance (BMER) effect in the d-electron-based two-dimensional electron gas (2DEG) at the SrTiO3 (111) surface. We find an evidence of a spin-split band structure with the archetypal spin-momentum locking of the Rashba effect for the in-plane component. Under an out-of-plane magnetic field, we find a BMER signal that breaks the six-fold symmetry of the electronic dispersion, which is a fingerprint for the presence of a momentum dependent out-of-plane spin component. Relativistic electronic structure calculations reproduce this spin-texture and indicate that the out-of-plane component is a ubiquitous property of oxide 2DEGs arising from strong crystal field effects. We further show that the BMER response of the SrTiO3 (111) 2DEG is tunable and unexpectedly large.Comment: 16 pages, 4 figure

Low-temperature and purification-free stereocontrolled ring-opening polymerisation of lactide in supercritical carbon dioxide

A stereoselective, solvent-free ring-opening polymerisation (ROP) of lactide (LA) in supercritical carbon dioxide (scCO2) is reported for the first time. The key aim is to exploit scCO2 to lower the temperature of traditional melt polymerisations, lowering the energy requirement and leading to cleaner polymeric materials. We have utilised a zirconium amine-trisphenolate initiator-stereoselective catalyst [(iPrO)Zr(OPh(tBu)2-CH2)3N] to yield highly heterotactic poly(lactide) (PLA) homopolymer (Pr = 0.74–0.84) from rac-LA, demonstrating control of the PLA microstructure in scCO2. In addition, high monomer conversion (86–93%) was achieved in short reaction time (1 h), affording poly(lactide) with a very low degree of transesterification and narrow molecular weight distribution. Most importantly, all the reactions were performed at only 80 °C, almost 100 °C lower than the conventional melt process (typically performed at 130–180 °C), representing a very significant potential energy saving