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101.
This study investigated failures of prospective memory (PM) as a relevant but neglected error type in medicine. A patient simulator was used to investigate PM failures. The influence of subjective importance (high, low) and type of intention (educational, internal, external) on the (missed) execution of intention was investigated in a 2 x 2 design. The effects on missed executions by importance (high < low) and type of intention (educational < external < internal) were hypothesized. Of 73 valid intentions in 40 prepared simulator scenarios 19 (26%) were missed overall. A total of 64% of unimportant and 80% of important intentions were executed 79% of educational 67% of external and 72% of internal intentions were executed. Neither difference was statistically significant using chi(2) tests. Interaction was significant for missed executions (p = 0.025; n = 19; df = 2; chi(2) = 7.41) and for executions (p = 0.002; n = 54; df = 2; chi(2) = 12.50). Despite low statistical support and some methodological limitations, it was possible to show that PM failures are relevant to patient safety and that patient simulators are a suitable but so far unused tool for their investigation. 相似文献
102.
Arvidsson I Arvidsson M Axmon A Hansson GA Johansson CR Skerfving S 《Ergonomics》2006,49(11):1052-1067
Operators with identical, demanding computer work (90 female and 97 male air traffic controllers) were found to have high prevalences of disorders (assessed by questionnaire and physical examination) in neck, shoulders and upper back. In spite of the identical work, the women displayed higher prevalences than the men (e.g. neck diagnoses 21% vs. 4%). Disorders in elbows, wrists and hands were less common, with similar rates in both genders. Generally, the psychosocial work environment (assessed by questionnaire) was found to be good, but with large inter-individual variation. Women experienced lower decision latitude than men, particularly regarding influence and freedom at work, but perceived higher social support. Physically, the work was characterized by relatively low angular velocities of upper arms (measured by inclinometry) and wrists (right: < 1 degrees/s during 19% of time, measuring by goniometry), dynamic muscular activities and high time fractions of rest in the trapezius and forearm extensor muscles (measuring by electromyography). There were only minor differences between the genders. 相似文献
103.
Khan Z Balch T Dellaert F 《IEEE transactions on pattern analysis and machine intelligence》2006,28(12):1960-1972
In several multitarget tracking applications, a target may return more than one measurement per target and interacting targets may return multiple merged measurements between targets. Existing algorithms for tracking and data association, initially applied to radar tracking, do not adequately address these types of measurements. Here, we introduce a probabilistic model for interacting targets that addresses both types of measurements simultaneously. We provide an algorithm for approximate inference in this model using a Markov chain Monte Carlo (MCMC)-based auxiliary variable particle filter. We Rao-Blackwellize the Markov chain to eliminate sampling over the continuous state space of the targets. A major contribution of this work is the use of sparse least squares updating and downdating techniques, which significantly reduce the computational cost per iteration of the Markov chain. Also, when combined with a simple heuristic, they enable the algorithm to correctly focus computation on interacting targets. We include experimental results on a challenging simulation sequence. We test the accuracy of the algorithm using two sensor modalities, video, and laser range data. We also show the algorithm exhibits real time performance on a conventional PC 相似文献
104.
Image-based stained glass 总被引:1,自引:0,他引:1
Brooks S 《IEEE transactions on visualization and computer graphics》2006,12(6):1547-1558
We present a method of restyling an image so that it approximates the visual appearance of a work of stained glass. To this end, we develop a novel approach which involves image warping, segmentation, querying, and colorization along with texture synthesis. In our method, a given input image is first segmented. Each segment is subsequently transformed to match real segments of stained glass queried from a database of image exemplars. By using real sources of stained glass, our method produces high quality results in this nascent area of nonphotorealistic rendering. The generation of the stained glass requires only modest amounts of user interaction. This interaction is facilitated with a unique region-merging tool 相似文献
105.
SLIM (spectroscopic localization by imaging), a tool for in vivo magnetic resonance spectroscopy that provides compartmental spectra from relatively few phase-encoded data, is limited by the inhomogeneities within each compartment. It is shown that the SLIM-derived spectra approach the average compartmental spectra as the number of phase encoded data approaches infinity, and the convergent rate of the error for each compartment is proportional to the size of the compartment. Numerical simulation studies are conducted to confirm the convergence property. A detailed discussion of the result is provided. 相似文献
106.
Yankov DY Schreiter S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1993,40(4):431-434
A hollow cathode maskless plasma etching method for fabrication of thin quartz membranes is presented. A special geometric arrangement of electrodes and substrates allows the complete plasma structure (plasma sheath, bulk plasma) to be transferred to the substrate area during the etching process. The process has successfully been used in preparing thin quartz membranes with plane-convex and plane-parallel shape, and thicknesses of less than 5 mum. Vibration modes in these thin quartz membranes are calculated using the method of equivalent resonant radius. The membranes are used for realization of bulk acoustic wave resonators at fundamental frequencies above 60 MHz. Good agreement between theoretical and experimental characteristics is achieved. 相似文献
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