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171.
A novel three-dimensional eye tracker is described and its performance evaluated. In contrast to previous devices based on conventional video standards, the present eye tracker is based on programmable CMOS image sensors, interfaced directly to digital processing circuitry to permit real-time image acquisition and processing. This architecture provides a number of important advantages, including image sampling rates of up to 400/sec measurement, direct pixel addressing for preprocessing and acquisition, and hard-disk storage of relevant image data. The reconfigurable digital processing circuitry also facilitatesin-line optimization of the front-end, time-critical processes. The primary acquisition algorithm for tracking the pupil and other eye features is designed around the generalized Hough transform. The tracker permits comprehensive measurement of eye movement (three degrees of freedom) and head movement (six degrees of freedom), and thus provides the basis for many types of vestibulo-oculomotor and visual research. The device has been qualified by the German Space Agency (DLR) and NASA for deployment on the International Space Station. It is foreseen that the device will be used together with appropriate stimulus generators as a general purpose facility for visual and vestibular experiments. Initial verification studies with an artificial eye demonstrate a measurement resolution of better than 0.1° in all three components (i.e., system noise for each of the components measured as 0.006° H, 0.005° V, and 0.016° T. Over a range of ±20° eye rotation, linearity was found to be <0.5% (H), <0.5% (V), and <2.0% (T). A comparison with the scierai search coil technique yieldednear equivalent values for the systemnoise and the thickness of Listing’s plane.  相似文献   
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Temperament and Character Inventory (TCI) and background questionnaire data were collected from a sample of men and women organ donation advocates (N = 362) as part of a national study to investigate their personality characteristics, temperaments, and attitudes about organ donation advocacy. Goals included identifying unique traits for advocates, and response consistency between the TCI and questionnaire. The TCI results included high scores on Cooperativeness and Self-Directedness, and low on Harm Avoidance dimensions. The questionnaire results indicated that most advocates were White, married, college-educated females, who typically spent less than 2 hr with potential donor families, were satisfied with life and job, and believed they would be in a donation position 2 years from the time surveyed. TCI and questionnaire measures were correlated for Self-Transcendence and Spirituality, Helpfulness and Job Satisfaction, and Compassion and Identification variables.  相似文献   
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Weber  Michael 《Philosophical Studies》2003,116(2):171-181
Philosophical Studies -  相似文献   
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This study examined effects of message and program sensation value, sensation seeking, and drug use on visual attention to televised anti-drug public service announcements (PSAs) among 318 18–22-year-olds, who were placed individually in a simulated home environment with the opportunity to read from print media selections and/or watch a half-hour TV program including two presentations of the test PSA. The TV program was high or low in sensation value. High sensation seekers paid greater attention to high sensation value programming and to PSA embedded in such programming, whereas low sensation seekers paid greater attention to PSA embedded in low sensation value programs. Ongoing attention to a program may help to sustain attention to a subsequent PSA. The findings relate to an activation model of information exposure and indicate that program sensation value and sensation seeking are important factors to be considered in the placement oftelevised drug abuse prevention messages.  相似文献   
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Modeling the learner is a central aspect of intelligent tutoring systems and knowledge-based help systems that support learners in complex problem-solving domains. In this article, the episodic learner model ELM is introduced as a hybrid system that analyses novices' solutions to programming tasks based on both rule-based and case-based reasoning. ELM behaves like to a human tutor. Initially, ELM is able to analyze problem solutions based only on its domain knowledge. With increasing knowledge about a particular learner captured in a dynamic episodic case base, it adapts to the learner's individual problem-solving behavior. Two simulation studies were performed to validate the system. The first study shows that the system can learn which rules are applied successfully to diagnose code produced by programmers and that using this information reduces the computational effort of diagnoses. Using information from the episodic learner model additionally speeds up the diagnostic process. The second study shows that ELM is able to predict individual solutions. Finally, correspondences and differences to related systems are discussed.  相似文献   
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