8,471 research outputs found
A Time Comparison of Computer-Assisted and Manual Bathymetric Processing
We describe an experiment designed to determine the time required to process Multibeam Echosounder (MBES) data using the CUBE (Combined Uncertainty and Bathymetry Estimator) [Calder & Mayer, 2003; Calder, 2003] and Navigation Surface [Smith et al., 2002; Smith, 2003] algorithms. We collected data for a small (22.3xl06 soundings) survey in Valdez Narrows, Alaska, and monitored person-hours expended on processing for a traditional MBES processing stream and the proposed computer-assisted method operating on identical data. The analysis shows that the vast majority of time expended in a traditional processing stream is in subjective hand-editing of data, followed by line planning and quality control, and that the computer-assisted method is significantly faster than the traditional process through its elimination of human interaction time. The potential improvement in editing time is shown to be on the order of 25-37:1 over traditional methods
Assessing patient and caregiver intent to use mobile device videoconferencing for remote mechanically-ventilated patient management
The Michigan Medicine adult Assisted Ventilation Clinic (AVC) supports patients with neuromuscular disorders and spinal cord injuries and their caregivers at home, helping them avoid expensive emergency department visits, hospitalization, and unnecessary or excessive treatments. Mobile device videoconferencing provides an effective capability for remote mechanically-ventilated patient management but must rely upon an unknown infrastructure comprising patient and caregiver mobile device ownership, connectivity, and experience—and intent to use the service if provided. The purpose of this study was to measure the extent of this infrastructure and the perceived ease of use, perceived usefulness, and intent to use this mobile device capability using a questionnaire based on the technology acceptance model (TAM).
Of 188 patients and caregivers asked, 153 (n = 153) respondents completed a questionnaire comprised of 14 demographic and 24 Likert-type questions. Inferential results indicated a significant correlation between perceived ease of use (PEU) and perceived usefulness (PU) of mobile devices in remote care and their intent to use them (sig. \u3c .001). Also, mobile device own/access significantly correlated with PEU and PU (p = .003 & .004, respectively), but not intent to use. No single demographic variable (age, distance to AVC, diagnoses, mobile device experience, tracheostomy, etc.) significantly correlated with intent to use. Descriptive results indicated a significant patient/caregiver provided infrastructure: 96% have cellular/WiFi/Internet access, 91% own or have access to mobile devices, 77% have downloaded apps, 68% have used videoconferencing, and 80% own between two and five ICT devices
Mapping and Characterizing Subtidal Oyster Reefs Using Acoustic Techniques, Underwater Videography and Quadrat Counts
Populations of the eastern oyster Crassostrea virginica have been in long-term decline in most areas. A major hindrance to effective oyster management has been lack of a methodology for accurately and economically obtaining data on their distribution and abundance patterns. Here, we describe early results from studies aimed at development of a mapping and monitoring protocol involving acoustic techniques, underwater videography, and destructive sampling (excavated quadrats). Two subtidal reefs in Great Bay, New Hampshire, were mapped with side-scan sonar and with videography by systematically imaging multiple sampling cells in a grid covering the same areas. A single deployment was made in each cell, and a 5-10-s recording was made of a 0.25-m2 area; the location of each image was determined using a differential global position system. A still image was produced for each of the cells and all (n = 40 or 44) were combined into a single photomontage overlaid onto a geo-referenced base map for each reef using Arc View geographic information system. Quadrat (0.25 m2 ) samples were excavated from 9 or 10 of the imaged areas on each reef, and all live oysters were counted and measured. Intercomparisons of the acoustic, video, and quadrat data suggest: (1) acoustic techniques and systematic videography can readily delimit the boundaries of oyster reefs; (2) systematic videography can yield quantitative data on shell densities and information on reef structure; and (3) some combination of acoustics, systematic videography, and destructive sampling can provide spatially detailed information on oyster reef characteristics
Turbulence model development and application at Lockheed Fort Worth Company
This viewgraph presentation demonstrates that computationally efficient k-l and k-kl turbulence models have been developed and implemented at Lockheed Fort Worth Company. Many years of experience have been gained applying two equation turbulence models to complex three-dimensional flows for design and analysis
- …